Repetitive spreading depression Essay Example for Free

Repetitive spreading depression Essay Jefferson (1996) notes that fear of crime is comprised of two distinct elements: personal fear and the use of a public fear of crime discourse. The latter could be variably invested, and could be more about crime than fear of crime. It was sometimes inflected more with anger. Some were invested in other discourses, such as neighborhood decline. It has been found that personal fears were normally of particular crimes, notably burglary or sexual assault, and could vary: inside and outside the home; and within and beyond familiar, local territory. Women are found to be more likely to express personal fear and men are more likely to reproduce the public discourse, especially older men (Jefferson, 1996). In discerning the distinction between the two genders and how each is affected by the fear of crime phenomenon, it was found that sex as such was not predictive of fear of crime; however, the effects of gender increased fears of victimization among women and sense of safety among men. While women feared for physical safety, men were in fear only as far as crime against them, not necessarily that of physical endangerment. Age was influential and found to be especially true for men. Anxieties about declining health and strength were sometimes expressed and are perceived to be in direct relation with a males concern of aging and becoming unable to protect himself in the event of a crime. Age did not appear to affect women in the same level as it was apparent that women of all ages are concerned about being unable to protect themselves against the possibility of physical crime. While older women were more likely to experience this type of fear, it was in no way peculiar to an age group among women. Findings help to establish the means to derive a more complete view of a given social environment (Koehly et al, 1998, p. 3). Research findings have helped to explain the measurement problems of crime and the fear of crime phenomena as it relates to gender depression. In two groups of mostly local, young or middle-aged, low-crime women, levels of fear and anxiety exceeded very low risk. Three of these women (married with children) worried excessively about burglary, or physical and sexual assault, and were hence judged depressively anxious. Their anxieties centered on their children but also included other members of the family, as well, revealing a core anxiety expressed as traditional, caring femininity. The lack of identity beyond that of being wife or mother combines with projection of protective agency onto the men in their families, leaving them with excess vulnerability that manifests in fears of burglary and/or assault. For two women in the study, fear of crime centered on fear of male sexual violence linked to violent, alcoholic fathers (Jefferson, 1996). II. SIDE EFFECTS OF DEPRESSION During the past decade the prevalence of eating disorders has increased among teenage and college-age American women. This increase is probably caused in part by societys idea of the ideal woman as being overly thin in order to be beautiful. Research has shown that anorexia nervosa consists of several psychopathological components as well as the physical components, and that the psychopathological characteristics often include such things as depression, anxiety, and difficulty in social situations, as well as low self-esteem (Wilcox, 1996). Adolescence is an intense time and is normally a time of physical changes as well as psychological changes. Females in particular seem to experience stress that is not experienced by their male peers. Females commonly experience depression during adolescence and other characteristics such as obsessiveness, compulsion and general reticence are quite common. While most anorexics have co-occurring clinical depression there are others suffering from anxiety, substance abuse or personality problems as well as an increased risk of suicide. Parks et al (1997) notes that within nonclinical samples, body image distortions have been associated with lowered self-esteem, depression, and chronic dieting (p. 593). The vicious cycle that exists with depression and female eating disorders serves to perpetuate the mental imbalance. Indeed, the consequences are far greater than just being overweight. Obesity, in and of itself, leads to a number of other diseases and complications that can significantly shorten a persons life. Of the long list of ailments, those at the top include heart disease, some cancers, diabetes, high cholesterol and blood pressure, and gallbladder disease. However, the mental distress such behavior causes is a significant concern, for a poor emotional outlook also takes its toll on the body. A common denominator among women with eating disorders is the overwhelming feeling of inadequacy they experience. Attempts to control their problem usually prove futile, which serves to plummet them even further and further into the depths of shame and depression. Based upon an article from the British Medical Journal entitled Male Sexual Problems, the findings indicate that male sexual function is so completely interwoven with other factors that there is no one single factor that can be considered the cause of sexual dysfunction. Dysfunction is often the result of factors such as complications from illness, general poor health or even side effects from treatment of other illnesses. Impotence is the major common side effect of many drugs, and it has also been a known side effect of aging, anxiety and depression. Male sexual dysfunction is also a known result of all forms of psychiatric disorder either directly or indirectly, with the side effects of drugs taken in conjunction with psychiatric disorder leading to sexual dysfunction such as depression. As sexual function continues to wane, the incidence of increased depression becomes cyclical in nature (Gregoire, 1999). CHEMICAL ASPECT Establishing the determinants of depression and gender in relation to the death of astrocytes in the brain, one is compelled to investigate the myriad experiment data that has surfaced since it was first surmised that the two entities had any connection to each other. Indeed, it has been found that the lack of astrocytic activity in the brain is an integral component to the overall concept of depression; it is with this information that the psychological community has become better equipped to address the relationship between astrocytic death and depression. Considered for decades to be a disease of the insane, depression has finally been recognized for the debilitating and emotionally unbalancing illness it truly is. With an astounding fifteen million Americans suffering from clinical depression a full five percent of the entire United States population it can no longer be looked upon as nothing more than merely the blues. Additionally, another five percent are victims of occasional despondency, with one of every six people succumbing to a significant depressive episode at some point throughout their lives. Depression often hits the elderly more than any other age group; however, with each passing year the average age of sufferers continues to drop. The field of psychology utilizes a number of statistical procedures in order to effect the applicable findings. According to Kendall (1991), the typical procedure behind such research is accumulated by way of study reviews, which employ the use of methodological considerations. These include deciding upon outcome measures, regulating therapy quality, as well as investigating client and therapist characteristics and the therapeutic relationship (Kendall et al, 1991, p. 78). There exist a number of issues that serve to influence the comparison modes, such as side effects, compliance and quickness of action, which must also be taken into overall consideration when determining the data. Among the variables that exist within the framework of statistical procedures, defining whether or not there is a difference between gender participation is a significant consideration. One study in particular from the National Institute of Mental Health Treatment of Depression Collaborative Research Program noted the differences between male and female patient statistical findings after a number of procedures were rendered. Zlotnick (1998) notes that depending upon the type of treatment each individual received placebo/clinical management; cognitive-behavioral therapy; interpersonal therapy; or imipramine/clinical management it was established that the final outcome was not influenced by gender. While the role of gender was examined in the process and outcome of therapy in the treatment (Zlotnick et al, 1998, p. 655) by reproducing the same findings in relation to psychotherapeutic treatment methods, it was determined that the second set of findings were the same. Researchers have been making the connection for some time now between depression and the death of astrocytes, noting that the astrocytes being essential for the brains nerve cells have been discovered to have healing properties. Pennisi (1999) notes how neurobiologists are beginning to recognize the regeneration components of astrocytes. Its going to make [neurobiologists] look at these cells in more detail. It will be interesting to see if they can be purified and used in [brain] repair (Pennisi 1999, p. PG). Understanding the roles that neurons and astrocytes play in the body helps one to fully comprehend why there may be a strong connection to depression. Astrocytic responsibility includes maintaining the blood brain barrier (BBB), as well as providing structural support, protection and repair of the central nervous system (CNS). Neurons, on the other hand, are the vital links between electrical impulses and the nervous system. Repetitive spreading depression (SD) waves, involving depolarization of neurons and astrocytes and up-regulation of glucose consumption, is thought to lower the threshold of neuronal death during and immediately after ischemia (Miettinen et al, 1997, pp. 6500-6505). In postulating the hypothesis that the growth or death of astrocytes somehow affects depression, it is relatively easy to recognize the fact that without the necessary astrocytes in place, conducting the brain-healing processes that they have been discovered to posses, it triggers within the brain the inability to maintain a sense of perspective. A kind of star-shaped brain cell that helps support surrounding nerve cells plays a much more pivotal role in maintaining the brains vitality than researchers had thought astrocytes double as neural stem cells, the source of new nerve cells (Pennisi, 1999, p. PG). Wineke (1996) notes the importance of ongoing research into the very real possibility that the absence of astrocytes serves to adversely effect brain function. Twenty years ago, the ideas we are studying were considered eccentric and fanciful. Now, this is really where its at (Wineke, 1996, p. 1G).

Passionate About Teaching Essay example -- Personal Narrative Educatio

Ending Statement Feminist and Critical Pedagogies I came back to graduate school last semester at the ripe-old age of 31, unsure of what I wanted to get out of it. I had spent a year in graduate studies in English at the University of Maine about six years earlier, but left because I wasn't ready to commit to an academic life. In the six years since I left Maine, my life had been anything but academic. For the first year or so, I "temped" at conventions and tradeshows, went on auditions and performed in regional theater. Then a friend of mine introduced me to her acting teacher, and I got involved in a two-year intensive acting program which forced me to look at myself and my life deeply (and luckily got me into therapy)! During that time I began a temp job at a small executive search firm where a few acting friends also worked. The job turned permanent and lasted over three years while I finished my acting program and began auditioning. Looking back now, I guess the problem was, once I finished class, I wasn't the same person who h ad originally gone out on auditions. I found myself reading books on writing (never acting) on my lunch breaks from the stifling office secretarial job. But people who asked about my life heard about my auditions and singing classes and wish to be on Broadway. I never looked at the fact that that wish was a very old, childhood wish which had slowly stopped giving me what it had for so long: something to dream about, aspire to. Something, I now admit, to make me interesting. The decision to leave it behind was painful (no one outside of "the business" could understand why I would want to leave behind such a glorious, exciting dream. Interestingly, all of my friends who were at various levels of s... ...at at least I now know that I need to teach--in some format, somewhere, and I need to apply what I've learned and continue to learn and question my own learning. But I can't decide if going on for a PhD is really what I want anymore. I always thought that was the mark of success. But I wonder if it will really allow me to work with the students I am most interested in helping. I am particularly interested in working with those who didn't get enough out of school but who decided to come back and give it another try, to see if they'd find something different this time around. I want to provide something different. I know I want to keep teaching and talking about teaching. I know I want to keep the hope that teaching writing is valuable and opens up possibilities for students who maybe thought they had none. Is that too naive? Maybe. But it seems like it's worth a try.

A Severed Head by Iris Murdoch Essay

Iris Murdoch constructs the novel, considered widely to have ushered in the Sexual Revolution of the 60s and 70s in England, with a first person male character, Martin Lynch-Gibbon. Martin is an upper class wine merchant, and it is with him that the novel begins, as we are given a picture of him lying in bed with his younger lover, Georgie, a student at Oxford, in the bliss of a vigorous, sexually driven relationship alongside a stable and convenient marriage. However, it is soon after this, when upon returning home, that his pampered wife Antonia tells him that she has been in love with his psychoanalyst and a family friend, Palmer Anderson. They wish to continue their cordial relationship with Martin, though Antonia has decided to seek divorce and marry Palmer. Martin falls back on his relationship with Georgie Hands, though we are given a sense at this point in the story, that the vigor is no more to be found, and it is reminiscent of something like Florentino’s womanizing in an attempt to rationalize the meaning of the loss he has suffered in Marquez’ ‘Love in the Time of Cholera’. It is Fermina’s rejection that drives him into a situation of bankruptcy, and it is here too that Martin tries to keep the different pieces together, though with a sense of loss that had made his relationship with Georgie complete. This missing part is his sense of security, his marriage of convenience, and a wife that he is otherwise indifferent to, Antonia. It is also the sense of having lost her to his friend, when he had taken for granted that fact that his ‘maleness’ in his liaison with Georgie had made him something of an artifact, a severed head to be held onto by the anthropologist; A man who would not lose his wife’s attentions. As a wine merchant, he chooses whiskey as a preference, and as a Marquezian lover, misinterprets his own charm. What is to be understood is that Antonia can only be truly free when she has broken out of the construct in which she finds herself pampered, materially lack of want, but missing a sort of impulsive romanticizing that will give her otherwise mundane life an aesthetic appeal. She needs to be tested for her love, and this can only happen when another male is involved, preferable someone close to and trusted by Martin himself. Thus, the betrayal is complete. Martin refuses to acknowledge the ethical impunity involved in his affairs with college girls, and the in his brazen pursuit and courting of Honor Klien. His decision to break into her house tells us again that his impulses will bring him no romantic merit, but only add to the tragicomic reality of a middle age well off man looking for sensual adventure but in a society that is already so riddled with misplaced and mismatched relationships, that each encounter will reveal a murkier reality to him. His breaking into Honor’s house finds her in bed with her half brother. This can only mean chaos for him. In his infatuation, childlike advances steadily give him a sense of failure, and slowly, acceptance. Martin is shown in a hedonistic light, and so are the other characters at different times in the novel. The pursuit of pleasure is seen as worthwhile in itself, though whether it conforms to conventions, or places them in opposition to a strangely rebellious modernity, is where Murdoch toys with the idea of a new sexual order to replace what England had come to be known for throughout the 17th to 19th centuries. At different times, the characters try to assert that they are independent agents, and by virtue of being so, they must naturally seek pleasure as their objective. Freud’s theories of motivation in human nature is a slight variant of this belief, and slowly we com to be acquainted with Freudian ideas, as relationships are confused, partners become parents and love finds expression in incest. Martin’s tragicomedy is reflected in several instances. For example when he moves out of their comfortable London home, move into a flat, and then moves back to their old residence. It seems as though his attempt to deal with the changes around him find expression in behaviour that he cannot himself explain. It was later that the pain came, a pain unutterably obscure and confused like that induced by some deprivation in childhood. (Oedipus complex) The familiar world of ways and objects within which I had lived for so long received me no more; and our lovely house had put on suddenly the air of a superior antique shop. The things in it no longer cohered together. It was odd that the pain worked first and most immediately through things, as if they had at once become the sad symbols of a loss which in its entirety I could not yet face. (p. 33) Here we get a glimpse of how childhood maturity plays a role in his relationships even as a 41 yr old adult with a fine business prospect. The deprivation that Martin claims to have a sense of, qualifies as Freud’s notion of the subjection of id, the subconscious, by the ego, conditioning. Martin’s frantic relocation, his breaking into Honor Klien’s home, are all an instance of hysteria, as is his self absorption when he is shown lying in bed with Georgie at the beginning of the novel. Such characterization has given critics the impression that Murdoch has adapted this book for the stage. The plot is simple and it is presented straightforwardly. Ethical questions come up in different discourses, but there is the impression at the end of the book that all the characters are flawed, through together, round and flat, in a given space. We as readers, watch them run around in different directions, emotionally, and sometimes come up against each other. To say that â€Å"the proper value is whatever gives you pleasure† is to say that â€Å"the proper value is whatever you happen to value†. Indeed, people begin to value different things at different times in the novel, and each change in heart raises moral questions. The symbol of the severed head, something that greatly fascinates Honor Klien, as a Lecturer of Anthropology, is something that Martin finds himself becoming. A severed head such as primitive tribes and old alchemists used to use anointing it with oil and putting a morsel of gold upon its tongue to make it utter prophecies. † He feels his adornment is something artificial that has been used to beautify a disgusting and decayed object. Toward the end of this novel two of the main characters (Honor Klein & Martin Lynch-Gibbon) are speaking after Martin discovers a secret about Honor, and she says to him â€Å"because of what I am and because of what you saw I am a terrible object of fascination for you. I am a severed head such as primitive tribes and old alchemists used to use, anointing it with oil and putting a morsel of gold upon its tongue to make it utter prophecies. And who knows but that long acquaintance with a severed head might not lead to strange knowledge. For such knowledge one would have paid enough. But that is remote from love and remote from ordinary life. As real people we do not exist for each other. † (182) The severed head can also be seen as a symbol of the Castration anxiety. It would be the father who would do the severing, against the son’s anxiety to dominate, especially in illicit sexual relations with the mother. In this context, the castration anxiety transmutes into a sort of mangled turnaround situation, when in the randomness of sexual anxiety, complexes are reversed and uncoordinated. Murdoch draws a close sketch of the other, the victim of the castration, though in this sense it is not so much the protagonists attempt at keeping the terms of association in equilibrium, the careful examination of loss and damage control. The male has been castrated, now he must survive in a world where he had thought that his emotionally charged liaisons with younger women would give him magnanimity over his nuptial vows. This is the irony which has been reversed on him, he is the fallen woman, the Lady who has stepped beyond the boundaries, and who must now experience perdition, a cleansing. Honor Klien is also an agency in the plot of the novel. It is her who discloses that liaisons between Georgie, Martin, his brother Alexander, Antonia and Palmer. Her affecting an introduction between Georgie and Alexander is the final destabilizing factor in Martin’s life, when he is sure that he has lost Antonia and Honor is beyond his grasp, the his final relationship with Georgie is put to threat. Honor seems like the feminist crusader, in her battle to bring sexual freedom to the women around her, an attitude that can find easy significance by her position as Georgie’s teacher at Oxford. Antonia easily fits as her aide; when Honor goes on to tell her and Palmer about Martin’s relations with Georgie that he has tried so hard to keep hidden even after he has symbolically broken away from his London high society moorings. Thus, she must act as the agent who forces upon him the task of reflection, thus reinterpreting his own history and that of the women around him. As Tagore said of each of his female characters, particularly of his protagonists, that they must go through the test of fire to be able to prove their existence in a society that demands absolute obedience from thinking women. Murdoch, as a female writer coming up in the coffee table age when sexuality was beginning to be openly discussed in the London circles, seems to offer a similar retribution of her male first person characters, to which she has attributed the female gaze. The gaze is an important cultural symbol that is seen in Tennyson’s poem, ‘The Lady of Shallot’. The lady can see the masculine space only through a glass mirror, while the man sees the lady, only later and in her death, and passes a flippant remark on her glassy countenance. She, in fact, has become the mirror herself. Martin similarly is an embodiment of the emotional turmoil that his class witnessed as a whole, and the failure of on man would go on to symbolize the failure of his entire class. Thus, while a crusader works on both ends of the sexuality debate, one is the pragmatic woman of the 20th century, while the other is the new man confused by changing roles and mores. Murdoch uses other recognizable symbols as well. The weather often corresponds with the moods of her characters. The dense fog over London is symbolic of his trance like inability to not bring his life back on his own terms. His acceptance towards the end of the novel has something of a Stephen Blackpool in him; through there is no fatalism to his relationships and the nature of his life. He must struggle, though only with himself, to bring about an external transformation. A severed head is sometimes seen as a satire, or a farcical novel, where people and customs are shown in an ironic stance to give us alternating points of view. It is because of this that it is so hard to pass a judgment on any of the characters in the novel. It occupies the grey mass between what we know and whet we are afraid to find out.

Definition of Theoretical Yield in Chemistry

Theoretical yield is the quantity of a product obtained from the complete conversion of the limiting reactant in a chemical reaction. It is the amount of product resulting from a perfect (theoretical) chemical reaction, and thus not the same as the amount youll actually get from a reaction in the lab.  Theoretical yield is commonly expressed in terms of grams or moles. In contrast to theoretical yield,  the actual yield  is the amount of product actually produced by a reaction. Actual yield is usually a smaller quantity because few chemical reactions proceed with 100% efficiency because of loss recovering the product and because other reactions may be occurring that reduce the product. Sometimes an actual yield is more than a theoretical yield, possibly because of a secondary reaction that yields additional product or because the recovered product contains impurities. The ratio between actual yield and theoretical yield is most often given as percent yield: Percent yield Mass of actual yield / Mass of theoretical yield x 100 percent How to Calculate Theoretical Yield Theoretical yield is found by identifying the limiting reactant of a balanced chemical equation. In order to find it, the first step is to balance the equation, if its unbalanced. The next step is to identify the limiting reactant. This is based on the mole ratio between the reactants. The limiting reactant is not found in excess, so the reaction cannot proceed once it is used up. To find the limiting reactant: If the quantity of reactants is given in moles, convert the values to grams.Divide the mass of the reactant in grams by its molecular weight in grams per mole.Alternatively, for a liquid solution, you can multiply the amount of a reactant solution in milliliters by its density in grams per milliliter. Then, divide the resulting value by the reactants molar mass.Multiply the mass obtained using either method by the number of moles of reactant in the balanced equation.Now you know the moles of each reactant. Compare this to the molar ratio of the reactants to decide which is available in excess and which will get used up first (the limiting reactant). Once you identify the limiting reactant, multiply the moles of limiting reaction times the ratio between moles of limiting reactant and product from the balanced equation. This gives you the number of moles of each product. To get the grams of product, multiply the moles of each product by its molecular weight. For example, in an experiment in which you prepare acetylsalicylic acid (aspirin) from salicylic acid, you know from the balanced equation  for aspirin synthesis that the mole ratio between the limiting reactant (salicylic acid) and the product (acetylsalicylic acid) is 1:1. If you have 0.00153 moles of salicylic acid, the theoretical yield is: Theoretical yield 0.00153 mol salicylic acid x (1 mol acetylsalicylic acid / 1 mol salicylic acid) x (180.2 g acetylsalicylic acid / 1 mole acetylsalicylic acid Theoretical yield 0.276 grams acetylsalicylic acid Of course, when preparing aspirin, youll never get that amount. If you get too much, you probably have excess solvent or else your product is impure. More likely, youll get much less because the reaction wont proceed 100 percent and youll lose some product trying to recover it (usually on a filter).