Rhetorical Analysis Essay Example for Free

Rhetorical Analysis Essay Everyone else got to decide what would become of their lives, while she was now going to have everything decided for her. While Kim tells her story, she makes several statements that key on the readers’ emotions and get us to take her side. Kim uses good imagery when she tells about her village being burned down and her clothes scorched off. She says â€Å"I saw an airplane getting lower and then four bombs falling down. I saw fire everywhere around me. Then I saw fire over my body, especially on my left arm. My clothes had been burned off by the fire. Anyone who could imagine this happening to a nine year old wouldn’t be able to help feeling sorry for this person. To make matters for the little girl worse, she was then forced to become a poster child for the Vietnamese government to show the rest of the world. Kim’s freedom to become what she wanted was taken from her. While telling her story, she does a very good job using these rhetorical pathos to make the reader feel sorry for her and take her side. In the story, â€Å"Untold Stories of Kindness†, an American soldier tells about the brutal reality of war. He explains that even though you may not agree with the reason for the fight or even know the truth behind the war, if you are a soldier, you have to do your job and continue fighting. He hits on the point that people want to help each other even in times of war and despair. He says that if everyone will just accept people who are different, the world will be a more peaceful place. His idea that people always want to help each other is supported by an example of a time he remembers people helping each other during his campaign in the Iraq war. After one particular fire fight that lasted nearly eight hours, Iraqi civilians helped the American soldiers clear the streets of wounded men and try to aid their injuries. People would also care for children, rebuild hospitals and schools, and feed the poor. The author of this essay uses strong imagery to make the reader have emotion towards his story. He tells about the time when insurgents detonated several car bombs killing over a hundred people. The number of people killed in this incident helps to emphasize the reality of all the people who dying in this war. He says â€Å"Cars were covered in blood as if they’d been hit with a paint sprayer. † This makes the reader try to imagine what he had to see and tries to make the reader feel the same emotions he has toward the situation. The rhetorical pathos used here are very similar to the pathos used by Kim in her story. Both of these essays made good points support the logic behind the statements and opinions in their stories. They also used good details and imagery so the audience could picture some of the things they had to see. The imagery in these stories tried to make the readers feel emotional and take the authors’ sides.

Effect of Peers and Gender on Risk Taking Decisions

Effect of Peers and Gender on Risk Taking Decisions The Effect of Peers and Gender on Risk Taking Decisions on Breaking the Rules of College Students Frances Mae H. Balandan Jaymie Aileen T. Huang Patricia Audrey D. Lansang Louie Belle M. Regente Dorothy Joy S. Sy Abstract Keywords: peers, genders, rules, risk-taking The researchers would like to know if clustering and gender affects the decision making of college students that involves risk. Clustering refers to the participants in whether they are classified in a group of friends or acting alone in a situation on making a risky behavior. The typical finding is that, on the average, subjects (group) shift toward greater risk; that is, the group will most likely decide on the risky option than an individual deciding on his or her own. This is the prototype of the group-induced shift toward risk, or simply the risky shift (Clark, 1973). There are theories, such as the social comparison theory, that emphasizes that people with in a group decides differently than people in isolation (Levinger and Schneider, 1969). In terms of gender differences, male participants are more probable to engage in risky behaviors than female participants. In social decision making, males perceive less risk and are more likely to engage in greater risk. Boys’ risk judgments were signià ¯Ã‚ ¬Ã‚ cantly predicted by their ratings of injury severity (Harris, C. R. Jenkins, H., 2006). Female participants are less probable to engage in risk behaviors in the domains of health, gambling and recreational activities. Females judge the activities as less enjoyable than males (Harris, C. R. Jenkins, H., 2006). In terms of group differences, examples would be that couples on average are risk-averse in their choices, and that risk preferences are less diverse across groups than across individuals. Groups are more risk-averse in lotteries with low probabilities of winning the largest payoffs, but less risk-averse when these probabilities are high (He, H., Martinson. P., Sutter, M., 2011). The gender is a determinant on risky behaviors. Generally, males take more risks. But in some cases, females tend to make riskier decisions. A study showed that males tend to make riskier decision in terms of finances while females take more social risks (Menon, 2011). Risk attitudes expressed by groups and individuals dià ¯Ã‚ ¬Ã¢â€š ¬er. In most choice problems involving a safe and a risky option groups tend to take more risk (â€Å"risky shifts†) (Stoner, 1960). Further studies have shown that men prefer their decisions to be implemented as decisions in the group, while women are less likely to so. Risk attitudes in the individual decision-making task have no significant effect on the females’ decision, but have a positive effect for males (Gurdal, M.Y., 2010). Other studies have also shown that adolescents are likely to do risky decision making as compared to adults, because they are prone to the influence of the peers and they tend to conform. They do not want to feel left out because they want to be part of the group, and adolescents are more easily convinced towards risky choices. This not applicable for adults, because they are more mature and self-reliant meaning they can do it independently without relying on the other’s help. (Gardner and Steinberg, 2005) The researchers would like to know the following: Does gender affect the risky decision making of an individual? Does clustering affect the risky decision making of an individual? In this research, the researchers generated four hypotheses: If a group of students are exposed to a risk-taking situation on breaking the rules, then the group consensus will be riskier than the average of the initial individual decisions. If an individual student is exposed to a risk-taking situation on breaking the rules, then s/he will take on a lower risk than the average of the group of students. If a male student is exposed to a risk-taking situation on breaking the rules, then he will take on a higher risk than female students whether be in group, pair or individual decision. If a female student is exposed to a risk-taking situation on breaking the rules, then he will take on a lower risk than male students whether be in group, pair or individual decision. The purpose of the study is to know if the inclusion of a person in a group would influence his/her making risky decisions and to know if the gender of a person matters in making risky decisions. This research will be a breakthrough for parents and counselors in dealing with their son/daughters and clients in terms of risk-taking decision making on breaking the rules. This research is specified to know how and when college students are more inclined to do riskier behaviors. This can help prevent the circumstances and unfortunate effects to take place. This research will also be helpful in terms of being a new discovery as it will be set in the Philippines. Most researches are conducted to study western participants and graduate students. In the group’s study, we will concentrate on college students. The possible difference may lay in the different religion and culture that we have from the western countries. The different concepts the Filipinos have as a community, the different beliefs and the different perceptions may influence the results of this experimental research. Methods Participants The sample consisted of 200 undergraduate Lasallian students, men and women of ages 18 and above. The participants will be chosen via random sampling by asking some students for a few minutes of their time to participate in this experiment. Those willing to participate will be asked to fill up the consent form and log-in sheet before starting the experiment. Research Design Between-subjects mixed design will be used. The independent variables are college students. The levels are individual, and group. The dependent variable is decision upon result of risk taking. Procedure Participants were gathered via random sampling and participated in the experiment It will conducted in a laboratory and done in individually A participant will be asked to read risky situations, and be asked what are the chances that they will do the risky behavior (breaking the rule). The participant will be randomly placed in a risky situation where s/he will is alone or with his/her peers. In this experiment, we will measure the difference of the participants’ decision on whether they will break the rule if they are hypothetically with their group or acting alone. References Clark, R. D., III, Crockett, W. H., Archer, R. L. Risk-as-value hypothesis: The relationship between perception of self, others and the risky shift. Journal of Personality and Social Psychology ,1971,20, 425-429. Gardner, M. Steinberg, L. (2005) Peer Influence on Risk Taking, Risk Preference, and Risky Decision Making in Adolescence and Adulthood: An Experimental Study. Developmental Psychology. Retrieved from http://uwf.edu/smathews/documents/peerroleinrisktakinggardnerandsteinberg.pdf Gurdal, M.Y.(2010) Deciding to Decide: Gender, Leadership and Risk-Taking in Groups. Retrieved from http://eaf.ku.edu.tr/sites/eaf.ku.edu.tr/files/erf_wp_1028.pdf Harris, C. R. Jenkins, H. (2006). Gender Differences in Risk Assessment: Why do Women Take Fewer Risks than Men? Judgment and Decision Making, 2006, 1(1), 48–63, Retrieved from http://journal.sjdm.org/jdm06016.pdf He, H., Martinson, P., Sutter, M. (2011).Group Decision Making Under Risk: An Experiment with Student Couples Retrieved from https://gupea.ub.gu.se/bitstream/2077/28122/1/gupea_2077_28122_1.pdf He, H., Martinson. P., Sutter, M. (2011). The Influence of Religious Priming on Self-Control and Risk Taking http://archives.ubalt.edu/ub_archives/inspired_discoveries/pdf/ADAMDspFINAL.pdf Jiang F. X., Jiang, Z. Kim. K. A., Zhang, M. (2013). Family-firm risk-taking: does religion matter? http://www.lingnan.net/seminar/upload/file/20130922/20130922103555225522.pdf Levinger, G. and Scheinder, D. J. (1969): â€Å"Test of the †risk is value† hypothesis,† Journal of Personality and Social Psychology, 11, 165-169 Menon, D. (2011, July 25). PRESS RELEASE. Association for Psychological Science RSS. Retrieved January 19, 2014, from http://www.psychologicalscience.org/index.php/news/releases/who-takes-risks.html Stoner (1961): â€Å"A comparison of individual and group decisions under risk,† unpublished thesis, MIT School of Management. Instruments Individual: Instructions: Read each situation carefully. Rate yourself to how much you are willing to do the stated situation, with 1 being the lowest and 10 being the highest. 1. You noticed that your teacher in your math class rarely checks the attendance. Everyone also noticed that some of your classmates are usually absent and cutting their class because the professor’s style of teaching is mundane. You sometimes ditch class with your classmates, but you noticed that you already exceeded the maximum number of absences allowed. You cannot cut the class more than 5 times. You are still tempted to cut the class, because you know that the professor rarely checks attendance. The risk is that the professor might have a roll call, thus leading you to a failing grade at the end of the term. The chances are __ in 10 that I will cut that class. 012345678910 2. You are required to write a group research paper for an English class. The topic must be new and something relevant to your course. You must contribute to writing the research paper. The paper is almost finished except for one significant part of the paper. The deadline is fast approaching you only have until 10pm of that night to finish the paper. You are tempted to plagiarize a portion of someone else’s work by claiming the paragraph of the person’s paper as your own without citation. The risk here is with rise of sophisticated anti-plagiarism software free for use on the Internet, there will be a chance of being caught with the act of plagiarism that will merit a failing grade. The chances are __ in 10 that I will plagiarize, copy a portion of that person’s work and not cite this person’s work. 012345678910 3. You are a part of a cheating chain (a group of students who pass the answers of one to another during a quiz). There are ten of you in the cheating chain a class. The teacher normally sleeps during examination, but he records the class on his phone. After two quizzes of not getting caught cheating, despite the presence of the phone, on the third exam, one of your cheating buddies was caught through the recording camera of the phone. He was the only one who was caught, and only received a warning and a zero on the exam instead of failing the entire course with a disciplinary demerit. The fourth exam is in a few minutes, and the only way to pass is through cheating. You are in desperate need of a high grade. With the fact that out of three exams, one out of the ten of you was only caught cheating, and that the teacher may be stricter due to catching one. What are the chances of you still partaking in the group’s cheating activities or abstain from it? The chances are __ in 10 that I will partake in the cheating chain. 0 1 2345678910 Group: Instructions: Read each situation carefully. Rate yourself to how much you are willing to do the stated situation, with 1 being the lowest and 10 being the highest. 1. You and your four friends noticed that your teacher in your math class rarely checks the attendance. Everyone also noticed that some of your classmates are usually absent and cutting their class because the professor’s style of teaching is mundane. You sometimes ditch class with your classmates, but you noticed that you already exceeded the maximum number of absences allowed. You cannot cut the class more than 5 times. You and your four friends are still tempted to cut the class, because you know that the professor rarely checks attendance. The risk is that the professor might have a roll call, thus leading you to a failing grade at the end of the term. The chances are __ in 10 that I will cut that class. 012345678910 2. You and your seven friends are required to write a group research paper for an English class. The topic must be new and something relevant to your course. Each member of the group must contribute to writing the research paper. The paper is almost finished except for one significant part of the paper. The deadline is fast approaching you only have until 10pm of that night to finish the paper. Your group is tempted to plagiarize a portion of someone else’s work by claiming the paragraph of the person’s paper as your own without citation. The risk here is with rise of sophisticated anti-plagiarism software free for use on the Internet, there will be a chance of being caught with the act of plagiarism that will merit a failing grade. The chances are __ in 10 that I will plagiarize, copy a portion of that person’s work and not cite this person’s work. 012345678910 3. You are a part of a cheating chain (a group of students who pass the answers of one to another during a quiz). There are ten of you in the cheating chain a class. The teacher normally sleeps during examination, but he records the class on his phone. After two quizzes of not getting caught cheating, despite the presence of the phone, on the third exam, one of your cheating buddies was caught through the recording camera of the phone. He was the only one who was caught, and only received a warning and a zero on the exam instead of failing the entire course with a disciplinary demerit. The fourth exam is in a few minutes, and the only way to pass is through cheating. You are in desperate need of a high grade. With the fact that out of three exams, one out of the ten of you was only caught cheating, and that the teacher may be stricter due to catching one. Will the cheating chain be active during the fourth exam? The chances are __ in 10 that I will partake in the cheating chain. 0 1 2345678910

Effect of Hormones on Aggressive Behaviour

Effect of Hormones on Aggressive Behaviour The role of hormones in mediating aggressive behaviour How hormones can trigger and influence aggression in animals and humans has interested many researchers in the last six decades (Brooks-Gunn, Graber, Paikoff, 1994). Scientists realised soon that aggressive behaviours has to be always set in a larger context. The larger context can never be neglected while investigating complex human behaviours. This applies especially when considering the hormonal contributions to aggressive behaviour since far more than one link seems to exist between hormones and aggression. For instance, the hormonal control of parental, sexual and reproductive behaviour crucially determines aggression in both humans and animals. Parents of many animal species are increasingly aggressive while experiencing hormonal changes, for example, during lactation and parturition as they strive to defend their offspring from enemies (Beach, 1979). The aim of this paper is to evaluate the study on hormones and aggressive behaviour in the evolutionary context. Nonetheless it is not intended to conceptualise this evolutionary context without relation to other domains such as the social or cognitive one as these domains are inextricably linked. â€Å"A developmental perspective of aggression thus is based on the assumption that aggressive behavior is multidetermined and dynamic over the life span, and a product of a complex continuous interaction of the multiple psycho-bio-social changes.† (Ramirez, 2003; p.622). Aggression The fact that multiple modulators for aggression seem to exist makes it more difficult to reach conclusions. An additional problem is that the usage of the word aggression is too broad and there is yet not consensus over how it can be actually defined (Kavoussi, Armstead, Coccaro, 1997). Aggression has been predominantly related to an emotional state that individuals frequently describe as involving a strong drive to inflict harm and emotions of disregard and hate. However, overt aggression comes, in contrast to the described inner feeling of hate, in different forms. Predatory aggression, for instance, refers to the feeding behaviour of animals and is represented by attacks directed at natural prey. It has been demonstrated that the majority of vertebrates display aggression between two males of the same species while only some animals display maternal aggression. Fear-induced aggression, on the other hand, appears when an animal is anxious and/or incapable to escape from a perceiv ed dangerous situation. Irritable aggression, however, comes frequently close to uncontrollable rage and is triggered by immense pain or frustration (Rosenzweig, Breedlove, Reiman, 2002). Nelson (1995) reported how male sex hormones play a significant role in various forms of aggressive behaviour like for example in within-species social interactions and encounters. As a consequence, aggressive behaviour between males increases on the verge to sexual maturity. Experiments with male mice have demonstrated that their aggressiveness levels rise significantly during puberty while immature mice display more violent behaviours against each other when they are treated with androgens (McKinney Desjardins, 1973). Puberty and Hormonal Change Given the dramatic changes that occur in endocrine physiology at puberty, it is not surprising that increases in testosterone are hypothesized to be related to increases in aggression. This explains why testosterone has been the most investigated hormone in its research. The wealth of evidence supporting the ability of testosterone to facilitate aggressive behaviour in a broad number of mammal species has led to wonder about its potential role in human aggression. Wingfield and colleagues (1987) were among those researches who successfully demonstrated that the amount of displayed aggression in many species is related to the amount of seasonal testosterone change. Yet experiments with youths experiencing puberty yielded equivocal results. Book and collaborators (2001) for instance conducted a meta-analysis on 45 independent studies and came to the conclusion that the mean weighted correlation of these studies was only weakly positive (r = 0.14). This finding was congruent with Archer’s (1991) meta-analyses as he had also found rather marginally significant positive relationships between testosterone levels in humans and aggression. Experiments investigating the on the effects of castration on subjects illustrated more convincingly how inextricably aggressive behaviour is linked to hormones. Conclusively, castrated males displayed less aggressive behaviour due to the decreased androgen production. If, in turn, testosterone is injected into these castrated species one can again observe an increase in inter-male violent behaviour. Females are less often studies by researchers with regard to hormonal affects on aggression. This is due to the fact that males engage significantly more often in aggressive behaviour than females (e.g. number of male murderers is five times higher in the United States). Thus the predominant viewpoint among scientists is that males of most species are the more aggressive and violent sex. Consistently, recent research has found more support for a link between androgens and aggressive affect for boys entering puberty (Olweus et al., 1988) but less strong associations for girls (Paikoff Br ooks-Gunn, 1990). Nevertheless some studies found that in some species like Hamsters the female sex is more aggressive. However, this was not anymore the case when the female Hamsters entered the estrus stage. As a matter of fact, not all studies have supported the notion that the amount of hormones, especially androgens, is negatively associated to aggression levels. Ehrenkranz and colleagues (1974) for example demonstrated that testosterone levels of humans were positively related to aggressiveness while Kreuz and Rose (1972) could not find a significant correlation between levels of testosterone and aggressiveness in prisoners. Nonetheless Dabbs and Morris (1990) maintained with the help of their study on military veterans that testosterone levels can be linked at least to violent antisocial behaviour. More recently Dabbs and Hargrove (1997) revealed that high testosterone levels are a remarkable characteristic and predictor of female prisoners who are convicted of self-initiated violent crimes. At least two confounding variables exist Research has also demonstrated the existence of at least two confounding variable which have a significant influence on the relationship between hormones and aggressive behaviour. Bernstein and Gordon (1971) showed that both monkeys and mice who come out as winners of an aggressive interaction display increased testosterone levels whereas the losers experience a decrease in androgens. Consequently, the winners become more aggressive while the losers are less prone to exhibiting aggressive behaviour towards their own and other species. One could conclude that it was more a consequence rather than a cause that the more aggressive prisoners in Dabbs and Hargroves (1997) experiment had higher testosterone levels. Surprisingly not only the winners of aggressive encounters but also the triumphant of sport competitions experience observable increases in their testosterone levels. It goes further that this increase is not only experienced by those who actively participate and win in the spor ting event but is even experienced by those who support and cheer up the winning side or individual (Bernhardt, 1997). As even chess players display after having lost chess matches lower levels and after having won higher levels of testosterone it was concluded that another confounding variable mediates between aggression and testosterone because chess players are hardly aggressive in their normal behaviour. Regardless of these confounding variables sexual assaulters, aggressors and criminals have been often castrated in the past in order to decrease both their sex and aggression drives. The results of these studies reported that criminals were less susceptible to aggressive behaviour after having experienced a decrease in sex hormones induced by their castration (Brain, 1994). Nowadays, however, ethical issues and concerns have become increasingly important and thus it is debatable and questionable whether these kind of forced surgical interventions are ethically justifiable and tenable. Serotonin and Aggressive Behaviour The synaptic transmitter serotonin seems to have as well a profound impact on aggressive behaviour in both humans and animals. In contrast to testosterone, however, a negative association between aggression and brain serotonin activity has been reported in past studies. Higley and collaborators (1992), for instance, investigated the activity of the neurotransmitter serotonin in around 30 monkeys in an observational study. The researchers ranked the monkeys according to their aggressive activities on the island where they were freely living and compared their ranks with the amount of serotonin brain activity. Their results demonstrated that serotonin levels are negatively correlated with aggression. Virkkunen and Linnoila (1993) supported these findings with their own study. They showed that individuals who consume alcohol excessively have comparatively lower serotonin metabolites concentrations (e.g. HIAA concentrations) in their cerebrospinal fluid. These applied also to animal tort uring children (Kruesi, 1979) and due to aggressive behaviour expelled American Marines (Brown et al., 1979). As a matter of fact, serotonin levels are affected by environmental context and stimuli. Dominant and high ranking primates for example who stand on the top of the hierarchical social status ladder display greater serotonin levels than primates who rank lower in the pecking order. If however the higher ranked primates loses his social status he analogously experiences a decrease in serotonin levels. Testosterone and Aggressive Behaviour Schaal and colleagues (1996) investigated more recently the association between physical violence and social dominance of pubescent male youths and their respective testosterone levels. It was shown that less socially dominant youths had lower levels of testosterone in comparison to socially more dominant peers who possess concurrently bigger amounts of testosterone amounts. Nevertheless, this finding could not be repeated with aggression levels as those pubescent youths who were perceived as more aggressively behaving had significantly lower testosterone concentrations than those males who had a low history of being physically aggressive and violent. Thus it was concluded that testosterone was related not so much to antisocial characteristics than to experienced social status. In other words, those who successfully achieve higher social dominance statuses experience an increase in testosterone while those who fail to gain high social status face a reduction in their testosterone pro duction. Experiments with younger children (e.g. 5-year-olds) it was found that boys with higher testosterone concentrations were more playfully aggressive in social interactions. However, this relationship could neither be established with girls nor in play contexts (Ahedo et al., 2002). This again implies that testosterone levels are not solely a modulator of aggressive behaviour but rather a mediator of any kind of social behaviour. Additionally, Ahedo and collaborators study demonstrated that sex differences in behaviour establish themselves already very early on in life. In another study (van Goozen et al., 1998) the androstenedione, testosterone, dehdroepiandrostenedione (DHEA) levels in prepubescent boys exhibiting antisocial conduct disorders was examined. Van Goozen and colleagues results revealed that antisocial conduct disordered infants’ aggressiveness was not significantly relatable to testosterone. However, the more antisocially behaving boys had significantly higher than average androstenedione levels and modestly higher than average DHEAS levels. Researchers like Ramirez (2003) believed that studies such as these have the power to shadow doubt on the validity of testosterone as a biological control system for aggressive behaviour in postnatal life. Even later on in life testosterone levels seem only to represent the consequence rather than a cause of aggression as testosterone does not immediately lead people to be physically aggressive but their aggression is solely a response to cognitive and social stimuli and triggers (Brain Su sman, 1996). Studies on observed changes in concentration levels of testosterone and cortisol during aggressive behaviour and social stress serve as support for those researchers maintaining that both the evolutionary and social contexts and experiences have an essential impact on hormonal levels in humans. Thus â€Å"gonadal hormones, besides being only one of the multiple processes -biological, social, and cognitive, to influence aggression in children and adolescents, might also be a signal of aggression, or even more precisely perhaps, of social success.† (Ramirez, 2003; p. 630). These findings about serotonin and testosterone are according to Ramirez (2003) of utmost importance as they demonstrate that that experiences made in life can alter both brain chemistry and hormonal production in fundamental ways. Thus it can be noted that social context and hormonal activities in the body and brain are inextricably linked. Past researches on abnormal (van Goozen et al., 2000) and normal (Nottelmann et al., 1987; Inoff-Germain et al., 1988) male and female children have revealed univocal associations between high hormone levels of adrenal origin like androstenedione or dehydroepiandrostenedione sulphate and aggression together with diverse other negative attributes such as antisocial behaviour, rebelliousness and anger. Furthermore, the fact that androstenedione which is a prevalent producer of androgens is linked to anger in females suggests that adrenal and not gonadal originated androgens play a fundamental part in determining the aggressive behaviour of the female sex. In addition to that, it has been found that serotonin is not the sole mediator of aggression but also noradrenergic, neuropeptides and GABA systems have been demonstrated to have an impact on aggressive behaviour. Additionally, estrogens, gonadotrophins, and prolactine have been identified as minor modulators. Thus, genetic and pharma cological experts have essentially extended the number of relevant hormones and neurotransmitters in the last couple of years (Nelson Chiavegatto, 2001). In conclusion, all the above findings fortify and support the currently predominant notion that aggression is not mediated by only one factor but by a network of many interplaying variables. References Ahedo, L., Cardas, J., Aizpiroz, A., Brain, P. F., Sanchez-Martin, J. R. (2002). Social behavior in male and female 5-year olds and its relation to salivary testosterone levels. The developmental origins of aggressive behavior (p. 53). Montreal: ISRA. Archer, J. (1991). The influence of testosterone on human aggression. British Journal of Psychology, 82, 1–28. Beach, F.A. (1979). Aggressive Behavior. Hormones and Aggression, 5(3), 313-316. Bernhardt, P. C. (1997). Influences of serotonin and testosterone in aggression and dominance: convergence with social psychology. Current Directions in Psychological Science, 2(6), 44-48. Bernstein, I. S., and Gordon, T. P. (1974). The function of aggression in primate societies. American Scientist, 62, 304-311. Book, A. S., Starzyk, K. B., Quinsey, V. L. (2001). The relationship between testosterone and aggression: A meta-analysis. Aggression and Violent Behavior, 6(6), 579–599. Brain, P. 1994. Hormonal aspects of aggression and violence. In A. Reiss, Jr., K. Miczek, and J. Roth (Eds.), Understanding and Preventing Violence, Volume 2., pp. 173-244 Washington DC: National Academy Press. Brain, P. F., Susman, E. J. (1996). Hormonal aspects of antisocial behavior and violence. In D. M. Stoff, J. Maser, J. Maser (Eds.), Handbook of antisocial behavior ( pp. 314–323). Hillsdale: Laurence Erlbaum. Brooks-Gunn, J. Graber, J.A., Paikoff R.L. (1994). Studying links between hormones and negative affect: models and measures. Journal of Research on Adolescence, 4(4), 469-486. Brown, G. L., Goodwin, F. K., Ballenger, J. C., Goyer, P. F., et al. (1979). Aggression in humans correlates with cerebrospinal fluid amine metabolites. Psychiatry Research, 1, 131-139. Dabbs, J. M., Jr., and Hargrove, M. F. (1997). Age, testosterone, and behaviour among female prison inmates. Psychosomatic Medicine, 59, 477-480. Dabbs, J. M., Jr., and Morris, R. (1990). Testosterone, social class and antisocial behavior in a sample of 4.462 men. Psychological Science, 1(3), 209-211. Ehrenkranz, J., Bliss, E., and Sheard, M. H. (1974). Plasma testosterone: correlation with aggressive behaviour and social dominance in man. Psychosomatic Medicine, 36, 469-475. Higley, J. D., Mehlman, P. T., Taub, D. M., Higley, S. B., et al. (1992). Cerebrospinal fluid monoamine and adrenal correlates of aggression in free-ranging rhesus monkey. Archives of General Psychiatry, 49, 436-441. Kavoussi, R., Armstead, P., Coccaro, E. (1997). The neurobiology of impulsive aggression. Psychiatry Clinic North America, 20(2), 395–403. Kreuz, L. E., Rose, R. M. (1972). Assessment of aggressive behaviour and plasma testosterone in a young criminal population. Psychosomatic Medicine, 34, 321-332. Kruesi, M. J. (1979). Cruelty to animals and CSF 5HIAA. Psychiatry Research, 28, 115-116. Inoff-Germain, G. E., Arnold, G. S., Nottelmann, E. D., Susman, E. J., Cutler, G. B., Chrousos, G. P. (1988). Relations between hormone levels and observational measures of aggressive behavior of early adolescents in family interactions. Developmental Psychology, 24, 129–139. McKinney, T.D., and Desjardins, C. (1973). Postnatal development of the testis, fighting behaviour, and fertility in house mice. Biology of reproduction, 9, 279-294. Nelson, R. J. (1995). Introduction to behavioural endocrinology. Sunderland MA: Sinauer Associates. Nelson, R. J., Chiavegatto, S. (2001). Molecular basis of aggression. Trends in Neurosciences, 24(12), 713–719. Nottelmann, E. D., Susman, E. J., Dorn, L. D., et al. (1987). Developmental processes in American early adolescents: Relationships between adolescent adjustment problems and chronological pubertal stage and puberty-related serum hormone levels. Journal of Pediatrics, 110, 473–480. Olweus, D., Mattsson, A., Schalling, D., Low, H. (1988). Circulating testosterone levels and aggression in adolescent males: a casual analysis. Psychosomatic Medicine, 50, 261-271. Paikoff, R.L., Brooks-Gunn, J., (1990). Associations between pubertal hormones and behavioural and affective expression. In C.S. Holmes (Ed.), Psychoneuroendoctrinology: brain, behaviour, and hormonal interactions (pp. 205-226). New York: Springer-Verlag. Ramirez, J.M. (2003). Hormones and aggression in childhood and adolescence. Aggression and Violent Behavior, 8, 621–644 Rosenzweig, M.R., Breedlove, S.M., Leiman, A.L. (2002). Biological Psychology. MA: Sinauer Associates. Schaal, B., Tremblay, R. E., Soussignan, R., Susman, E. J. (1996). Male testosterone linked to high social dominance but low physical aggression in early adolescence. Journal of the American Academy of Child and Adolescent Psychiatry, 35(10), 1322–1330. van Goozen, S. H., Matthys, W., Cohen-Kettenis, P. T., Gispen-de Wied, C., Wiegant, V. M., van Engeland, H. (1998). Salivary cortisol and cardiovascular activity during stress in oppositional-defiant disorder boys and normal controls. Biological Psychiatry, 43(7), 531–539. van Goozen, S. H., van den Ban, E., Matthys, W., Cohen-Kettenis, P. T., Thijssen, J. H., van Engeland, H. (2000). Increased adrenal androgen functioning in children with oppositional defiant disorder: A comparison with psychiatric and normal controls. Journal of the American Academy of Child and Adolescent Psychiatry,  39(11), 1446–1451. Virkkunen, M., and Linnoila, M. (1993). Brain serotonin, type II alcoholism and impulsive violence. Journal of Studies on Alcohol, 11, 163-169. Wingfield, J. C., Ball, G. F., Dufty, A. M., Hegner, R. E., et al. (1987). Testosterone and aggression in birds. American Scientist, 75, 602-608.

The Strengths and Limitations of Electrical Muscle Stimulation :: Exploratory Essays Research Papers

The Strengths and Limitations of Electrical Muscle Stimulation "Buy EMS, it'll burn calories and fat away." "One hour of EMS is equal to 300 to 400 sit-ups." "You can develop 19-22 inch arms!" They're new! They're hot! But do they work? You've seen them in the backs of magazines and on TV commercials- those advertisements form electronic fitness machines that tighten abdominals and give users huge biceps while watching TV or sleeping. These devices are based on electronic muscle stimulation. What exactly is EMS, what does it do, and, other than those muscle building, fat reducing claims, what are the current uses of electronic muscle stimulation. Electronic Muscle Stimulation (EMS) is a muscle exercise concept for use in one's own home. It is an established rehabilitative concept used for treating a variety of clinical problem involving the muscle skeletal, neuromuscular (relating to both nerve and muscle tissue) , genitourinary (relating to the genital and urinary organs) , and integumentary (administered by contact with the skin) systems(Leonard). The first recorded use of EMS for medical stimulation was recorded in 1783 (Creasey). This was used to restore respiration for people who had paralyzed/collapsed chest/lung muscles. After that, many Soviet and Eastern Olympic competitors used muscle stimulators to build and produce the same bulk in muscles that only steroids had promised. Now the system has finally reached the West. Once only available to doctors and therapists, EMS is now suggested for use by anyone participating in bodybuilding, power lifting, martial arts, boxing, or anyone simply wishing to achieve their optimal athletic ability. EMS is also recommended to athletes for warming up the muscles and increasing circulation prior to a workout routine (Schmidt). The Medical Advisory Committee has allowed the use of EMS systems by athletes since the 1972 Olympics (Muscle stimulators...). Many athletes use EMS to supplement their regular workout routines, while many doctors use it to aid in the rehabilitation of muscles f ollowing injury and to ease patients chronic muscle spasms and pain (Muscle stimulators...). The concept of electrical muscle stimulation is to use technologically advanced science that uses very mild electrical current to exercise your muscles. When one performs any exercise, their brain sends a message down the spinal cord through the nerves innervating all the muscles causing them to contract. An outside electrical source stimulates the nerves to send these signals to your muscle to contract. This is achieved by passing electrical currents through electrode pads placed over a muscle.

Time Essay example -- Literary Analysis, The Great Gatsby

Time, the most impersonal and brutal of juggernauts, cares for neither civilizations nor their cultures; it destroys with a simplistic ease that even the most ardent of warmongers could never achieve. How then can something as simple, as pure, and as vulnerable as a dream stand against the slow but steady stream of time, that beats like particles of sand against the bottom of an hourglass? For a dream to continue to nourish the minds of the masses generation after generation, it must adapt--change to better fit the new circumstances that a change in time invariably evokes. But as a dream changes, is it as pure, as innocent, and as high-minded as it once was? Could the American dream, which has hereto defined the very spirit of the era, have lost its original luster in its adaptation, mutation, and perversion? The American dream has traditionally been defined as the ability to achieve satisfaction, success, or greatness, through work. It states, rather ideally, that the only obstacle to greatness is contained within the dreamer and not the world; that if we as individuals work hard enough nothing can escape our grasp. Fitzgerald, in The Great Gatsby, explores the ever-elusive nature of the American dream as he questions the very basis upon which we identify ourselves with. Fitzgerald does not, however, question whether the American dream drives us towards greatness as it once did; rather he questions the deficiencies present in our ability to drive, and the path that we take. With every blossoming and withering flower, change of season, and revealed faà §ade, Fitzgerald chips away at the illusionary ‘greatness’ that so pervades the conception of the American dream, showing how its adaptations pervert its original spirit, an... ...onger attainable. The American dream has traditionally been defined as a westward movement, but with the census and Turner declaring the frontier closed, the American dream has been forced to evolve. With nothing lying to the West to explore, people go back East. Nick experiences this after returning from the war and feeling as if the Middle West was â€Å"like the ragged edge of the universe† (3). However Fitzgerald constantly asserts that the East has â€Å"a quality of distortion† (176). Going back â€Å"West from prep school† however, involves â€Å"long green tickets† and an â€Å"[unutterable awareness] of our identity with this country†¦before we melted indistinguishably into it again. That’s my Middle West.† (175-176). The West therefore is the true attainable American dream, but because the frontier is closed the American dream is â€Å"behind [us]†¦beyond the city† (180) and in the past.

Image Incentives for Environmental Management Essay

Investors are most perceptibly impressed by environmental management. A company that demonstrates sound and sustainable practices with respect to the environment wins the trust of fund managers who adopt risk management strategies for the long-term safety of capital. A business or even an arm of government that has large ‘eyesores’ in terms of waste, extravagant consumption and deleterious side-effects from use of its products and services, will find it impossible to attract fresh investment, or even to retain its equity, unless it is able to demonstrate clear ability to contain all the undesirable effects of its operations. Organizations with transparent environmental management systems will emerge as preferred destinations for public and private investment. Major accidents can threaten the continuance of both industry and government. The impacts of the Bhopal disaster on Union Carbide’s pesticide operations, and that of the atomic power plant accident in Chernobyl, are striking examples of how a sudden disaster can be the reason for an indefinite cessation of all activities for a running organization. Formal environmental management systems help to reduce probabilities of adverse incidents, to cope with the immediate effects of disasters, and for image recovery in the aftermath of such major incidents. The EMS has therefore image implications for organizations, apart from the actual aid that it would render internally. Industries with negative images in the public mind need independent certification of their environmental management systems more than others. The label of ISO can enable such enterprises prolong their market operations. Some communities may ask polluting and hazardous businesses to move away from them. Local governments do routinely place severe restrictions on chemical application-some cities in North America have even banned their use altogether. Such developments point towards the eventual demise of entire sectors of industry. Companies and organizations with long term stakes in such enterprises, can rescue their investments by adopting comprehensive environmental management standards. There are a large number of enterprises and organizations with products, services and activities that have no obvious effects on the environment. Even they may on life cycle analysis, find areas where they can contribute to conservation of key earth resources. Life saving health care services generates large quantities of infectious wastes. Electronic goods including computers contain plastics and heavy metals, the disposal of which threatens our future, in a field with such rapid obsolescence. Many consumer goods compete on the basis of elaborate and attractive packaging, which tends to be paper based, and therefore very demanding of vegetative cover. Bureaucracies, especially the armed forces, may run on enormous quantities of energy without consummate and durable benefits. Companies in ‘non-polluting’ fields of endeavor can achieve new breakthroughs by displaying foresight in environmental conservation terms. Environmental concerns are most attractive for the young. This may be because of the long-term perspectives in which related concerns lie. Companies that design and make products and services for the young, can often find environmental concerns to make special business sense. Many social organizations have large numbers of young people amongst their ranks of activists and followers, because they lay so much importance by the environment and its conservation. Any business or group activity that seeks the support and endorsement of the young must have defendable records of environmental management. Toyota leads automobile manufacturers which use achievements in energy and waste reductions, to reach out to the young and to increase their market shares of this demographic segment. Formal environmental management systems involve elaborate procedures. They use the best team building practices. Environmental management methods use some of the top business management resources. The technology encompasses all aspect of business and operations; it provides platforms for individual and group excellence. Firms and organizations with elaborate environmental management systems in place can attract and retain the best professional talent, because of the challenge and opportunity it presents. Conversely, companies and organizations with poor records of environmental conservation will find it increasingly difficult to build adequate human resources of the right quality. The reasons and benefits of certified environmental management are not confined to the ‘soft’ reasons of image and goodwill: there are concrete business advantages as well. Companies and service organizations that supply goods and services to downstream industries, can access additional markets by adopting environmental management systems. The latter have ‘domino’ effects and all those who adopt formal systems for environment care are generally obliged to make their suppliers conform as well. Vendors who opt to ignore environmental management systems, or who consider the costs to be too high, will find themselves isolated and excluded from increasing sections of their potential markets. Tenders for major construction and service projects may stipulate environmental requirements. Bids can be lost because potential winners for such contracts do not have the experience and resources to comply with tender conditions. Some bidders, who are not the lowest on price, may present environmental advantages and add-on services to support their bids. We may see more examples of this trend, especially when public funds are at stake. It is unlikely that any major tenders can exclude conditions related to environmental concerns. We know that investors value stocks more on the bases of their perceptions and sentiments, rather than by the cold facts and figures of financial statements and checks of dividend. Image plays a major role in building long term value for companies, especially leaders in mature markets. There is a recent trend towards Corporate Social Responsibility (CSR), which instigates firms to stray beyond the strict limits of their original purposes. CSR has little meaning for firms without EMSs. One can never tell when an acute and major adverse event may expose an errant company, but the erosion of credibility of all firms with pernicious abuse of the environment, is also certain. There are strong compulsions for companies to develop and to protect their images in the public eye through the shield of ISO 14001. ISO 14000 and Global Trends The Internet and the World Trade Organization have combined to give all businesses global potential. This is a double-edged sword, as the benefits come with certain tags. One of the important implications of globalization is the need to display effective commitment to environmental conservation. The latter is a prime concern of recent origin that permeates key markets everywhere (Hanson, A. J. not dated). The United Nations Commission on Environment and Development, also known as the Brundtland Commission, published in 1987, gives concrete credence for the inevitability of environmental concerns for all international transactions. The cause of sustainable development is well served by the ISO 14000 series. Business houses and social organizations are bound by some international treaties related to environmental protection. The Montreal Protocol of 1987 on ozone depletion, the Basel Convention of 1989 on the transport of hazardous wastes, the 1992 Framework Convention on Climate Change and the 1992 Convention on Biological Diversity, are the key ones. These international agreements act as competitive advantages for companies that can meet the technological challenges implied; companies that ignore international trends in environmental concerns, on the other hand, are doomed to exclusion from emerging frontiers of global business. The Agreement on Technical business to Trade (TBT) and the Code of Good Practice are strong albeit indirect influences by the World Trade Organization to impose environmental management on a trans-national basis. Imports in to a member country may be restricted by technical regulations and product standards. The latter can have strong environment norms, as for example in terms of air emissions. Product labeling requirements may also act as barriers for companies to export their goods, if they do not have a comprehensive environmental management system such as ISO 14001 in place. Since ecological labeling is based on life cycle analysis, international trade can dig deep in to production and purchase systems as a barrier to entry for companies that do not follow or use ISO 14001. The Strategic Advisory Group on the Environment (SAGE) has led the ISO to establish the following standards, each of which has severe impact on companies involved in international trade: Environmental Management Systems (EMS) Environmental Auditing (EA) Environmental Performance Evaluation (EPE) Life Cycle Analysis (LCA) Environmental Labeling (EL) Terms and Definitions (T&D) Environmental Aspects of Product Standards (EAPS). TC 207 has the international authority to set standards for environmental management systems. It has established a network of organized committees in many countries of the first world that give strong body and substance to the strict observance of environmental management standards by all companies engaged in global trade. TC 207 gives an undeniable message to global corporations to use systems such as ISO 14001. Environmental concerns have reached consumer groups, and they add great force to regulatory pressures on global companies to use the ISO 14000 series to respond to changing trends in customer demands. Companies that lack the abilities and the inclination to conserve the environment, face gradual extinction as they stand to lose custom. The net effect of these treaties and regulations is that business will get confined in stages to small pockets of the third world where international obligations do not apply, and where consumer awareness is low. Even these pockets will shrink to infinitesimal proportions with the passage of time. The future lies in business that meets global standards, and environmental management systems are an integral part of such standards. ISO 14001 is a structured way for all companies to strengthen their bases for the world-wide markets of the future. ISO 14001 and Profits Many business leaders will not invest the time and money required to obtain ISO 14001 registration, and to maintain it, for image reasons alone. However, they can be persuaded by arguments related to direct effects on the bottom line. ISO 14001 helps profitability in a number of ways (Case Studies 2002). Companies which have implemented ISO 14001 have the following experiences: 1. ISO 14001 makes the implementation of other standards in the ISO 14000 series easier. A company which invests in ISO 14001 can earn multiple returns by qualifying quickly and at low cost, for other certifications in the series. The profit implications of this competence will become an increasing lever of competitive advantage as countries and trading blocks insist on the consumer benefits that the ISO 14000 series offers. 2. Material and energy costs can be significant in total product costs. Much of the ISO 14001 process deals with reducing the amount of materials and energies needed to make each unit of a brand. This leads to direct cost savings. ISO 14001 also reduces the total cost of production by reducing waste management expenses. 3. ISO 14001 reduces the chances that a company may have to pay out large and unexpected amounts to help communities recover from pollution arising out of production and use of products. ISO 14001 protects operating profits from erosion due to recovery from pollution. 4. Recycling of waste is an important ISO 14001 priority. Parts recovered from a recycling process can act as raw materials for a new or a different production process, sometimes by a new entity at some other location. Regardless of the structure of a recycling process, there are always significant revenue potentials in the system. 5. ISO 14001 contributes positively to employee health and safety. It reduces employee-related costs in this manner, and improves productivity. ISO 14001 companies can expect better contributions from their human resources. 6. Insurance companies can be persuaded to reduce their charges as ISO 14001 improves risk management. The chances of adverse events reduce with ISO 14001 processes, and thereby reduce insurance costs. 7. ISO 14001 has international relevance. Companies that operate globally can avoid duplicating the costs of meeting local standards by seeking the universal nature of ISO 14001 certification. 8. Company valuation appreciates after an ISO 14001 certification, especially for relatively risky areas of business. Investors feel more assured about investing in stocks of companies that are able to manage their inherent risks in the transparent and professional ways of ISO 14001. 9. Companies can market their ISO 14001 certifications to gain market share. Customers may switch over to support companies who are able to inform them about the environmental benefits of the registration. ISO 14001 is a flexible system that adapts to the priorities of organizations that strive for its certification. It yields margin improvement through productivity achievements. It also protects future profits by contributing to the risk management capabilities of registered organizations. It can reduce insurance costs by managing product liabilities and reducing the probabilities of accidents, claims and other adverse incidents. Companies that use ISO 14001 experience profit growth and more assured future prospects as well.

Importance of Colloidal Dispersion in Pharmacy

Importance of colloidal dispersion in pharmacy Pharmaceutical Applications of colloids: Colloids are extensively used for modifying the properties of pharmaceutical agents. The most common property that is affected is the solubility of a drug . However, colloidal forms of many drugs exhibits substantially different properties when compared with traditional forms of these drugs. Certain medicinals have been found to possess unusual or increased therapeutic properties when formulated in the colloidal state.Another important pharmaceutical application of colloid is their use as drug delivery system. The most often used colloid type drug delivery systems include hydrogels, microspheres, microemulsions, liposomes, micelles, nanoparticles and nanocrystals. Here we mention the main characteristics of each colloidal delivery system. Hydrogels: Hydrogel is a colloidal gel in which water is the dispersion medium. It (also called aquagel) is a network of polymer chains that are hydrophilic, som etimes found as a colloidal gel in which water is the dispersion medium.Hydrogels are highly absorbent (they can contain over 99% water) natural or synthetic polymers. Hydrogels also possess a degree of flexibility very similar to natural tissue, due to their significant water content. These hydrogels have the ability to sense changes of pH, temperature, or the concentration of metabolite and release their load as result of such a change Natural and synthetic hydrogels are used for wound healing, as scaffolds in tissue engineering, and as sustained- release delivery systems.When used as scaffolds for tissue engineering, hydrogels may contain human cells to stimulate tissue repair, since they are loaded with pharmaceutical ingredients, hydrogels provide a sustained drug release. Light-sensitive, pressure- responsive, and electro-sensitive hydrogels also have the potential to be used in drug delivery. Environmentally sensitive hydrogels include slow response time, limited biocompatibi lity, and biodegradability. Hydrogel used as sustained-release drug delivery systems. it provide absorption, desloughing and debriding capacities of necrotics and fibrotic tissue. ydrogels that are responsive to specific molecules, such as glucose or antigens can be used as biosensors, as well as in DDS. Also used in disposable diapers where they â€Å"capture† urine, or in sanitary napkins, contact lenses (silicone hydrogels, polyacrylamides). Medical electrodes using hydrogels composed of cross-linked polymers (polyethylene oxide, polyAMPS and polyvinylpyrrolidone). hydrogel used as water gel explosives, rectal drug delivery and diagnosis. Other, less common uses include, breast implants, granules for holding soil moisture in arid areas, dressings for healing of burn or other hard-to-heal wounds.Wound gels are excellent for helping to create or maintain a moist environment, reservoirs in topical drug delivery; particularly ionic drugs, delivered by iontophoresis (see ion ex change resin), Common ingredients are e. g. polyvinyl alcohol, sodium polyacrylate, acrylate polymers and copolymers with an abundance of hydrophilic groups. Natural hydrogel materials are being investigated for tissue engineering; these materials include agarose, methylcellulose, hyaluronan, and other naturally derived polymers. However if the achievements of the past can be extrapolated into the future, it is likely that responsive hydrogels with a wide array of desirable properties will be forthcoming. Microparticles: Microparticles are small loaded microspheres of natural or synthetic polymers. Microparticles was initially developed as carriers for vaccines and anti-cancer drugs. More recently, novel properties of Microparticles have been developed to increase the efficiency of drug delivery and improve release profiles and drug targeting.Several investigations have focused on the development of methods of reducing the uptake of the nanoparticles by the cells of the reticuloendo thelial system and enhance their uptake by the targeted cells. Functional surface coatings of non-biodegradable carboxylated polystyrene or biodegradable poly (D,L- lactide-co-glycolide) microspheres with poly(L-lysine)-g-poly (ethylene glycol) (PLL-g-PEG) were investigated in attempts to shield them from nonspecific phagocytosis and to allow ligand- specific interactions via molecular recognisition.It was found that coatings of PLL-g-PEG- ligand conjugates provided for the specific targeting of microspheres to human blood- derived macrophages and dendritic cells while reducing non- specific phagocytosis. Microparticles can also be used to facilitate nontraditional routes of drug administration. It was found that Microparticles can be used to improve immunization using the mucosal route of administration of therapeutics. It was found in this study that mucosal route of administration of therapeutics can translocate to tissues in the systemic compartment of the immune system and prov oke immunological reactions. Micro & Nano-Emulsions:Microemulsions are excellent candidates as potential drug delivery systems because of their improved drug solubilization, long shelf life, and ease of preparation and administration. Three distinct Microemulsions- oil external, water external, and middle phase- can be used for drug delivery, depending upon the type of the dug and the site of action. In contrast to Microparticles, which demonstrate distinct differences between the outer shell and core, microemulsions are usually formed with more or less homogeneous particles. Microemulsions are use for controlled release and targeted delivery of different pharmaceutics agents.For instance, microemulsions were used to deliver oligonucleotides (small fragments of DNA) specifically to ovarian cancer cells. In contrast to microemulsions, Nanoemulsions consist in very fine oil-in-water dispersions, having droplets diameter smaller than 100 nm. Compared to microemulsions, they are in a me ta stable state, and their structure depends on the history of the system. Nanoemulsions are very fragile systems. The nanoemulsions can find applications in skin care due to their good sensorial properties (rapid penetration, merging textures) and their biophysical properties (especially their hydrating power).Liposomes: Liposomes consist of an outer uni – or multilamellar membrane and an inner liquid core. In most cases liposomes are formed with natural or synthetic phospholipids similar to those in cellular plasma membrane, because of this similarity, liposomes are easily utilized by cells. Liposomes can be loaded by pharmaceutical or other ingredients by two principal ways: Lipophilic substances can be associated with liposomal membrane, and hydrophilic substances can be dissolved in the inner liquid core of liposomes.To decrease uptake by the cells of the reticuloendothelial system and/or enhance their uptake by the targeted cells, the membrane of liposomes can be modifi ed by polymeric chains and/or targeting moieties or antibodies specific to the targeted cells, because they are relatively easy to prepare, biodegradable, and non- toxic, liposomes have found numerous applications as drug delivery systems. Liposomes are of colloidal dimensions and are preferentially taken up by the liver and spleen. Hence, principle of colloids is also used in targeted drug delivery system. Liposomes are used for drug delivery due to their unique properties.A liposome encapsulates a region on aqueous solution inside a hydrophobic membrane; dissolved hydrophilic solutes cannot readily pass through the lipids. Hydrophobic chemicals can be dissolved into the membrane, and in this way liposome can carry both hydrophobic molecules and hydrophilic molecules. To deliver the molecules to sites of action, the lipid bilayer can fuse with other bilayers such as the cell membrane, thus delivering the liposome contents. By making liposomes in a solution of DNA or drugs (which wo uld normally be unable to diffuse through the membrane) they can be (indiscriminately) delivered past the lipid bilayer.There are three types of liposomes – MLV (multilamellar vesicles) SUV (Small Unilamellar Vesicles) and LUV (Large Unilamellar Vesicles). These are used to deliver different types of drugs. Liposomes are used as models for artificial cells. Liposomes can also be designed to deliver drugs in other ways. Liposomes that contain low (or high) pH can be constructed such that dissolved aqueous drugs will be charged in solution (i. e. , the pH is outside the drug's pI range). As the pH naturally neutralizes within the liposome (protons can pass through some membranes), the drug will also be neutralized, allowing it to freely pass through a membrane.These liposomes work to deliver drug by diffusion rather than by direct cell fusion. Another strategy for liposome drug delivery is to target endocytosis events. Liposomes can be made in a particular size range that makes them viable targets for natural macrophage phagocytosis. These liposomes may be digested while in the macrophage's phagosome, thus releasing its drug. Liposomes can also be decorated with opsonins and ligands to activate endocytosis in other cell types. The use of liposomes for transformation or transfection of DNA into a host cell is known as lipofection.In addition to gene and drug delivery applications, liposomes can be used as carriers for the delivery of dyes to textiles, pesticides to plants, enzymes and nutritional supplements to foods, and cosmetics to the skin. Another interesting property of liposomes is their natural ability to target cancer. The endothelial wall of all healthy human blood vessels is encapsulated by endothelial cells that are bound together by tight junctions. These tight junctions stop any large particles in the blood from leaking out of the vessel.Tumour vessels do not contain the same level of seal between cells and are diagnostically leaky. This abil ity is known as the Enhanced Permeability and Retention effect. Liposomes of certain sizes, typically less than 200 nm, can rapidly enter tumour sites from the blood, but are kept in the bloodstream by the endothelial wall in healthy tissue vasculature. Anti-cancer drugs such as Doxorubicin (Doxil), Camptothecin and Daunorubicin (Daunoxome) are currently being marketed in liposome delivery systems. Micelles: Micelles are similar to liposomes but they do not have an inner liquid compartment.Therefore they can be used as water- soluble biocompatible micro containers for the delivery of poorly soluble hydrophobic pharmaceuticals. Similar to liposomes their surface can be modified with antibodies (immunomicelles) or other targeting moieties providing the ability of micelles to specifically interact with their antigens. One type of micelles pluronic block copolymers, are recognized as pharmaceutical excipients listed in the U. S and British Pharmacopoeia. They have been extensively used in a variety of pharmaceutical formulations including delivery of low molecular mass drugs, polypeptides, and DNA.Furthermore, Pluronic block copolymers are versatile molecules that can be used as structural elements of polycation- based gene delivery system. Nanoparticles: Nanocapsules are sub-microscopic colloidal carrier systems composed of an oily or an aqueous core surrounded by a thin polymer membrane. Nanoparticles are the colloidal particulate systems with size ranging between 1-1000 nm. Based on the arrangement of drug and polymer matrix, nanoparticles can be classified into two types: nanospheres and nanocapsules . In nanospheres, rugs are either adsorbed or entrapped inside the polymeric matrix. In nanocapsules, drugs are confined to the inner liquid core while the external surface of nanoparticles is covered by the polymeric membrane. polymeric nanoparticles have gained considerable attention as potential drug delivery systems due to its targetability to particular organ /tissue and ability to deliver protein and peptide via oral route. Nanoparticles for drug delivery are generally made up of biocompatible and biodegradable polymers obtained from either natural or synthetic source.Natural polymers include chitosan, albumin, rosin, sodium alginate and gelatin while, synthetic polymers include poly (lactic acid) PLA, poly (D, L-glycolide), poly (lactide-co-glycolide), poly (caprolactones) (PCL) and poly (cyanoacrylates). The kinetics of drug release from nanoparticles depends on the strength of hydrophobic interactions between the polymer and drug and polymer degradation rate. The uptake and distribution of nanoparticles depend on its size. Nanoparticles of size ~10 nm are utilized for extended circulation, while ~100 and ~200 nm particles are utilized for passive targeting and intracellular drug delivery respectively.Though nanoparticles have many advantages over other conventional drug delivery systems certain properties like surface hydrophobicity and surface charge needs to be altered so as to increase the uptake of nanoparticles into cells. This can be done by judiciously manipulating the use of polymers. Coating the nanoparticles with chitosan which is positively charged significantly enhances the uptake and modulates the drug efflux of anticancer agents. Moreover, attachment of poly (ethylene glycol) moieties to the surface of nanoparticles increases the hydrophilicity and hence decreases the uptake by macrophages.Recent studies by Yoncheva et al. concluded that amino-pegylated poly (methyl vinyl ether-co-maleic anhydride) nanoparticles were able to cross the cell membrane of the absorptive enterocytes in a better way. Nanoparticles are characterized by a variety of techniques such as dynamic light scattering (DLS), electron microscopy (TEM or SEM), atomic force microscopy (AFM), Fourier transform infrared spectroscopy (FTIR), x-ray photoelectron spectroscopy (XPS), powder X-ray diffraction (XRD), matrix-assisted laser de sorption/ionization time-of-flight mass spectrometry (MALDI-TOF), and magnetic resonance (NMR).Two technologies can be used to develop such Nanocapsules: the interfacial polymerization of a monomer or the interfacial nano deposition of a performed polymer. Solid lipid nanoparticles are developed at the beginning of the 1990’s as an alternative carrier system to emulsions, liposomes, and polymeric nanoparticles. They are used in particular in cosmetic and pharmaceutical formulations. A novel nano-particle based drug carrier for photodynamic therapy has been developed.This carrier can provide stable aqueous dispersion of hydrophobic photo-sensitizers; yet preserve the key step of photo generation of singlet oxygen, necessary for photodynamic action. Nanoparticles have also found applications as nonviral gene delivery systems. Advantages of nanoparticles a) Longer shelf-stability b) High carrier capacity c) Ability to incorporate hydrophilic and hydrophobic drug molecules d) Can be administered via different routes e) Longer clearance time f) Ability to sustain the release of drug ) Can be utilized for imaging studies h) Increase the bioavailability of drugs i) Targeted delivery of drugs at cellular and nuclear level j) Development of new medicines which are safer k) Prevent the multi-drug resistance mediated efflux of chemotherapeutic agents l) Product life extension Nanocrystals: Inorganic crystals that interface with biologic systems have recently attracted widespread interest in biology and medicine. To explore the feasibility of in vivo targeting by using semiconductor quantum dots (qdots), which are small (