Mobile Phones for University Students Essay Example for Free

Mobile Phones for University Students Essay Nowadays modern technology is developing so rapidly that people can hardly catch up with its pace. There is no doubt that mobile phones, as a new industry of modern technology, have got into people’s life. As sensitive reflectors of information and fashion, more and more mobile phone users have appeared in the campus everywhere. While some students are enjoying whatever mobile phones have brought to us, there are others who stand against it. This essay will explain the possible effects of mobile phone use on university students, focusing on the benefits and drawbacks. The main benefits of mobile phones in university are as follows. Firstly, there is no denying the fact that mobile phones have made campus life more convenient. A recent survey found that mobile phones are becoming part of university life and 99. 7% of students use their own mobile phones to communicate with others (Ransford, 2009). As it can be seen, mobile phones provide students with a fast and convenient way of communication, such as getting in touch with schoolmates and hunting for jobs, which was previously unimaginable. Secondly, instead of going to the PC lab and finding computers to look for news on current events, students can use mobile-network to search the Internet. It is by this means that university students can broaden their horizon and enrich their minds. Lastly, with the help of mobile phones, students can do work more efficiently. Many students in university treat mobile phones as electronic dictionary and chart with teachers for academic purpose. They share useful information related to their lessons and solve academic problems sometimes. In this way, mobile phones not only can save our time and energy but also help with our study. However, the negative effects are also obvious. Above all, more and more university students are indulged in Java QQ and online games, which make them weak in study. Moreover, some even use mobile phones to cheat in the examinations. It has been reported that almost 80% university students use Java QQ constantly and more than half of them are in favor of it. Only less than 1/3 of them comment that it is bad to our health and study if students spend too much time on Java QQ and online games. Some students even spend a whole day playing with their mobile phones and send thousands of short messages every day. If they do not use Java QQ a day, they will feel anxious (Yang, 2009). In other words, some university students have regarded playing with mobile phones as a kind of habit and fashion. In the second place, some students often make comparison of others’ mobile phones. They always want to own an attractive and high-grade one. Consequently, it costs them too much money and energy to buy a new style in order to gratify their vanity. Finally, mobile phones in university also bring some health risks, both physical and mental, if not properly used. It has been highlighted the fact that some pornographic video and photos of two U.  S. high school girls was spread so rapidly that even police were hard to stop them. In addition, District Attorney James B. Martin said that at least 40 Parkland High School students believed to have received the pornographic images (Rubinkam, 2008). It is really harmful to university students’ future development, especially those are immature. In conclusion, everything has its advantages and disadvantages, and mobile phone is no exception. On the one hand, using mobile phones in university can help students communicate with each other more convenient, have rich knowledge and study more efficiently. On the other hand, mobile phones can also have bad influence on learning; encourage students’ vanities as well as mental injury. In my point of view, therefore, there are three solutions which can solve this problem. Firstly the university authority should intensify publicity and education. Secondly coercive measures can be put into effect, such as shielding the mobile phones in classrooms and libraries. Lastly university students should promote themselves and fight temptation. A brighter future is awaiting us if we make good use of mobile phones.

Bycommitting suicide Essay Example for Free

Bycommitting suicide Essay Discuss the view that Eva Smith was an immoral troublemaker who, by  committing suicide, was responsible for her own fate, and the murder of her unborn child  This statement is neither right nor wrong, it has two different sides to it, and in this essay I shall try and discuss both sides of this opinion.  Eva Smith had an acceptable job at Mr Birlings factory, and she had the normal wages of a factory worker, but these wages were as low as the factory could make them, and they werent nearly enough to live off. With a few of her fellow workers Eva decided to ask for higher wages, instead of twenty-two and six they asked for twenty-five shillings a week, which is only two and a half shillings more, hardly a substantial increase. Their boss refused, so they decided to go on strike to try and get the rise that they wanted. However their pitiful savings didnt last long, and eventually they had to return to the factory, and ask for their jobs back. Most of the girls were taken on again, apart from the ring leaders, who were fired. Eva was one of these ring leaders, and she was fired along with the others. Mr Birling says that she was a good worker and that the foreman there told me he was ready to promote her into a leading operator head of a small group of girls. If Mr Birling himself said that she was a good worker then he didnt have to fire her, he could have kept her on and she would have worked even harder as a result of that. Also Mr Birling said that they should work for lower costs and higher prices, and why shouldnt Eva  strive for higher wages too? However no one forced Eva into taking part in the strike, and she should have been satisfied with the job that she had, she was better off than some people, and at least she had some wages. Also she would have known that it wasnt easy to find another job, and she shouldnt have risked so much on such a small pay rise, it was reckless and thoughtless of her to have gone on strike. After much hard searching and a stroke of luck, Eva managed to find another, very good job in Milwards, an expensive clothes shop. She was fired after only a couple of months, just when she felt she was settling down nicely (Inspector). She was fired through no fault of her own, but because of Shelia losing her temper, and because of Shelias jealousy of Eva. Shelia says that Eva was a very pretty girl with big dark eyes, and she looked as if she could take care of herself, so Shelia decided to use her power as a valued customer to fire her. There was nothing wrong with the way she was doing her work. They [the shop owners] admitted that. (Inspector). Shelia admits that she had been in a foul temper, and had taken it out on Eva by telling the manager of Milwards that if they didnt get rid of that girl, Id never go near the place again and Id persuade mother to close our account with them. All Eva had done is supposedly to smirk at the assistant whilst Shelia was trying on an ill-fitting dress. There is no proof that Eva had done this at all, and it is probably a figment of Shelias angry imagination at the time. Yet on the other hand, Eva may have smiled at the assistant because Shelia looked silly, to say doesnt she look awful (Sheila) and if she did, this was very presumptuous of her and she should have been more respectful of the customers. As a last resort to gain money, Eva (or Daisy, which she changed her name to) then went to the Palace Bar, and became a woman of the town. There was no other way for Eva to then make money apart from turning to prostitution. In the Palace Bar one night she was picked up by a friendly and handsome man, who offered her a set of rooms to stay in for a while, in fact he even insisted on Daisy moving into those rooms and he made her take some money to keep her going there (Gerald). Not surprisingly she said yes, for a woman in her position this must have been a lovely offer! She must have known what he would have wanted from her, but what he was  offering seemed so perfect, probably almost like heaven. He said he would supply food for her, and all she would have to do is offer herself to him in return. What woman in that situation would say no? She was broke, with no home, no way of earning an income, and it was stay with a nice man in a lovely set of rooms instead of prostitution. It wasnt remotely immoral of her to have taken Geralds money; he offered it freely to her, even insisted upon her taking it, and even though she did accept it, she also gave him what he wanted in return. Throughout the time she stayed with him, its not surprising that she gradually fell in love with him. He was so persuasive and charming, and she had never been cared for like that before, she  couldnt help but feel that way about him, he must have seemed like a saviour to her. Gerald says that she was intensely grateful and that he became at once the most important person in her life. Their relationship was completely dictated by Gerald; he was the one who started the relationship and if he wanted to see her, he would have to go to her, she could never come to him. Also Gerald only thought about his wants and needs during the relationship, he would never take into consideration that she  might miss him or she might wish he was with her more, it was only his thoughts that mattered. This is shown particularly by Gerald dropping Daisy as soon as he wanted to, when it was convenient for him. He didnt even think about whether it was convenient for her, he didnt ask her to leave, he just told her that she had to. Also Gerald knew that she had fallen in love with him, I didnt feel about her as she felt about me but he didnt let this bother him about leaving her, because he had never loved her, so it didnt matter that he was never going to see her. It was irrelevant to him that she loved him more than anyone else in the world; it didnt affect him. Then when he did ask her to leave she was very gallant about it (Gerald). This shows that she knew it wasnt going to last for ever; she wasnt stupid. However, on the other side of this point, it was stupid of Daisy to go to the Palace Bar in the first place. She knew what went on in the Bar, and she knew that the men didnt exactly treat the women there nicely. It was silly to put herself at risk to the rough-handling of men, and she should have expected what Gerald had done to her. Daisy should have tried for another job instead of going to the dangerous Palace Bar. She  could have at least applied for a factory job, like the one she had before, or she could have made an attempt to look for one. Also, she would have known that she would fall for this dashing young man who saved her from prostitution, and she should have refused his offer. She would have known that he wouldnt look after her forever, and she shouldnt have let herself get emotionally attached to him in the first place.

The Hardy Weinberg Theorem In Genetics Biology Essay

The Hardy Weinberg Theorem In Genetics Biology Essay Introduction The Hardy Weinberg Theorem is a mathematical formula that allows allele and genotype frequencies in a population of diploid or polypoid individuals to be interrelated, where the frequency of one allele is represented as p, and the frequency of the other is represented as q (the sum of which = 1.0). The sum of the different genotype frequencies (homozygotes and heterozygotes) also equates to 1.0. Where p and q are the frequencies of the alleles for a particular gene in a population, the genotype frequency can be expressed as: p ² + 2pq + q ² = 1 Where p ² = frequency of organisms that are homozygous for the first allele q ² = frequency of organisms that are homozygous for the second allele 2pq = frequency of heterozygous organisms The Hardy Weinberg equilibrium stays constant as long as there is random mating, no migration, no natural selection, no mutation and no genetic drift (N=infinite), (Fig. 1). N = infinite Figure 1. A graph to show the Hardy Weinberg Equilibrium. Put together using data from: Lori Lawsons lecture 15, Neutral Evolution and Genetic Drift, 2010 Therefore the population does not evolve. If an allele or genotype frequency is seen to change from one generation to the next then it is clear that one or more of the micro-evolutionary forces (mutation, migration etc) are acting on those traits in the population. Without mutation there are no new alleles or genes and so no evolution. Mutation must occur in the germ line to be significant in evolutionary terms. J. B. S. Haldane (1892-1964) stated that the number of germ cell divisions per generation is higher in males; therefore the mutation rate will be higher in males. Gene flow (also called migration) brings new genotypes into populations and is critical for the long term survival of a population, especially if it is a small population. For migration to be Catherine Carrick 200884273 effective in respect to evolution there must be successful reproduction among migrating populations. It is the movement of alleles between populations, not individuals. Wrights Island model of migration (Fig. 2) shows that migration homogenizes populations (where they consist of similar elements uniform throughout). Genetic drift is another form of micro-evolution and leads to random changes in allele frequencies. It is fundamentally a result of finite population size and has the most rapid and dramatic effect on small populations who show reduced variability. Drift increases divergence between populations so genetic variation must be replenished. Mutation replenishes variation and at equilibrium there is a balance between the rate of mutation and the rate of drift. Figure 2.Wrights island model. Put together using data from: Lori Lawsons lecture 15, Neutral Evolution and Genetic Drift, 2010 Charles Darwin (1859) defined natural selection (another micro-evolutionary force) with his four postulates; 1) individuals within populations are variable, 2) there is heritability (variation among individuals partly passed on from parents), 3) that in every generation there are some individuals that are fitter (survival/reproductive success) than others and 4) fitness is not random. Natural selection is the equivalent of differential reproduction as a result of an organisms interaction with the environment and the populations inherent variation. It acts on heritable (not acquired) characteristics at an individual level and not for the good of the species. However, the consequences occur in populations. This is demonstrated by melanism in the peppered moth (Biston betularia). The causes of melanism in the peppered moth have been well studied since the 1950s and show natural selection at work. Camouflage is key to predator avoidance in the peppered moth and there are two distinct mor phs. One being white with black or brown specks (typica) and the other predominantly black (carbonaria). The former is well camouflaged on trees with lichen on their bark and the later; better suited to dark or blackened bark. During the industrial revolution in the 19th century, an increase of soot and industrial pollution coincided with the appearance of the carbonaria form. Original studies on the relation between B. betularias crypsis and lichens failed to consider two important details; firstly, that the natural resting place of the moths is high in the canopy during the day and not on the trunk as previously thought, and secondly, human vision was used to simulate a birds view of the moths originally, but avian species are sensitive to different wavelengths of light and so will have a different view of the moths and their respective camouflage to that of humans. Taking this into consideration, Majerus, Brunton and Stalker (2000) devised a more systematic experiment to examine the UV characteristics of Catherine Carrick 200884273 both moth morphs and some of the lichens they rested on as demonstrated by the images in Fig. 3. Figure 3. The typica and carbonaria forms of the peppered moth as they appear in normal visible light (a), and as they appear under UV light (b). Image taken from MAJERUS, BRUNTON STALKER, 2000 It was their conclusion that moth colour provides sufficient camouflage both in human-visible and UV- spectra to crutose lichens (as appose to different lichen flora originally hypothesised to be rested upon by black and peppered morphs). Ultimately, strong selection pressures gave way to relatively rapid the evolution of the carbonaria form in industrialised areas due to the advantages of its dark colour (predator avoidance etc). Methods and Results Assignment 1: Testing the Hardy-Weinberg Principle: Method Using PopGenLab, we are able to set up hypothetical experiments to observe the factors that influence the Hardy Weinberg equilibrium in a population. We can do this by manipulating different input parameters (genotype frequency, tree type, number of stands (groups of trees), stand size (number of trees within a group), migration rate, mating pattern and disaster frequency). For this assignment the input parameters are as follows: Number of stands = 1 All other input parameters are left at default values (equal allele frequencies; genotype frequencies of 50% brown, 25% white, 25% black; equal proportions of each tree type; stand size of 4000; no migration; random mating; disaster frequency set at Never. Results Q 1.1) When looking at the allele and genotype frequencies, there is a change in both over time. All populations behave differently to one another. This is because the only active evolutionary force is genetic drift. Fig. 4 shows that allele frequencies change Catherine Carrick 200884273 over time due to genetic drift, but as all the conditions of the Hardy Weinberg equilibrium are fixed the allele frequencies must equal 1 and so the variation in allele frequency of A becomes the negative of the frequency of a. (Fig. 4). Figure 4. Showing allele frequencies changing over time due to genetic drift. Blue line = Allele A, Red line = Allele a, Green line = average over all stands for allele A Q 1.2) When the initial allele frequencies are changed to A=80% (p), a = 20% (q) (p ² = 0.8 x 0.8 = 0.64); AA = 64% (equilibrium reached after one generation) (Fig 6). If all the Hardy Weinberg conditions are all fixed, the equilibrium will always be reduced in the next generation (Fig.5 and 6). Fig. 5. shows the initial genotype frequency compared with Fig. 6. which shows the genotype frequency after one generation. The actual genotype frequencies (worked out with average stand number) match the Hardy Weinberg predictions as they stay within 1% of the previous generations genotype frequency, across every generation thereafter. However, the percentage may change by 1% due to genetic drift. Figure 5. Display of the initial genotype frequency. Catherine Carrick 200884273 Figure 6. Shows the Hardy Weinberg equilibrium is reached after one generation where 0.64=64% homozygous AA individuals. Assignment 2: Genetic Drift Method Q 2.1) Firstly we ran an experiment with default values for all the Hardy Weinberg conditions and 100 populations. We then ran a series of experiments with 100 populations and default parameters for all conditions except tree stand size which was systematically reduced for each experiment. We recorded the effects on allele and genotype frequency (below). Fig. 7 shows that stand size 10 produced the largest fluctuations of allele frequencies, and displayed the most cases of allele fixing. Results Stand size = 4000 (carrying capacity) Allele frequency- the average remains constant for A and a Genotype frequency stays relatively constant throughout. Stand size = 2000 Allele frequency the average show slight variation Genotype frequency stays relatively constant. Stand size = 1000 Allele frequency the average starts to diverge more with each generation from F45 (generation 45) onwards showing a lot more variation than in larger stand sizes Genotype frequency the average frequency stays constant although there is some variation compared with larger stand sizes Catherine Carrick 200884273 Stand size = 500 Allele frequency The average shows variation in the later generations Genotype frequency the average stays relatively constant but still with more variation than in any other larger stand thus far Stand size = 250 Allele frequency the average shows some variation in the mid-generations, but this returns to a 50:50 frequency in the later generations Genotype frequency on average, the frequency of both white and black variations of moth increases and shows a large variation between stands. Heterozygosity the brown variation decreases by 9% over 100 generations Stand size = 100 Allele frequency the average shows more variation, but to the point where in some stands alleles within individual populations become fixed Genotype frequency the frequency of homozygotes increases. In some stands the homozygosity (black) becomes fixed, phasing out the other tow variations (white and brown) Heterozygosity drops by 22% Stand size = 50 Allele frequency frequencies become fixed for a single allele quickly (by F23) Genotype frequency Many stands become fixed for one variation within a few generations Heterozygosity drops by 33% after 100 generations Stand size = 10 Allele frequency becomes fixed within a population after two generations, and continues to become fixed in other populations. By F77, all are fixed Genotype frequency every single genotype becomes homozygous or extinct Heterozygosity by F77 all heterozygosity is lost and by F100 there are only homozygous populations, with the other (70%) becoming extinct There are many variations in allele and genotype frequency between different stands because as the stand number decreases, the chance of genetic drift increases. Figure 7 shows that at stand size 10, heterozygosity was lost completely by F77. Catherine Carrick 200884273 Figure 7. (stand size 10): this produced the largest fluctuations of allele frequencies, and displayed the most cases of allele fixing. (Blue = A, Red = a, Green = average) Q 2.2) As the stand size decreased, so did the heterozygosity. Populations began fixation in stand size 100 to stand size 50. As the stand size decreased, the number of fixed alleles increased. When the carrying capacity became too small, there was not enough variation to prevent fixation. Random mating account for the variation between fixed and non-fixed alleles in stand size 100 and stand size 50. Fig. 8. shows that with a stand size of 10, heterozygosity diminished completely by F77. Therefore, the smaller the population, the quicker heterozygosity is lost. Figure 8. Question 2:2 (stand size 10): This shows the heterozygosity diminished completely by F77. The green line (average) tends to diminishing heterozygosity. Catherine Carrick 200884273 Figure 9. Question 2:3 (stand size 10): Shows population of stand number 15 and how it fluctuates around the average value, it also shows that when the population dwindled to a certain point, it wasnt able to re-establish the numbers enough to prevent extinction. Q 2.3) Yes populations from stand size 10 became extinct (70% of them) therefore, as the carrying capacity decreases, the risk of extinction increases. There is variation within generations due to factors like predation or whether the offspring are male biased for example. There may be a lower population size in the next generation depending on mating strategies (random mating) and occasionally, the parameters reach a point of no return and the population can not recover and so becomes extinct. Others avoid extinction because the experiment is random. Fig. 9. (where stand size = 10) shows population of stand number 15 and how it fluctuates around the average value, it also shows that when the population dwindled to a certain point, it wasnt able to re-establish the numbers enough to prevent extinction. Assignment 3: The Influence of Mating Patterns on Population Genetics Method In this experiment we set all default parameters except for the number of tree stands which was set to 100. The first experiment was carried out with random mating, and the subsequent experiments with non-random mating. We then varied the population size as before, this time to compare the effects of assertive mating with genetic drift. Results Q 3.1) The effects of 25% assortative mating: Genotype frequency 25% assortative mating causes an increase in homozygotes, and heterozygosity is lost by F80 Allele frequency (produces a sigmoidal shaped graph). All become fixed for a single allele. Heterozygosity the average heterozygosity is lost at F80 Catherine Carrick 200884273 50% assortative mating: Genotype frequency all homozygotes with an almost 1:1 ratio aa being slightly more dominant Allele frequency (sigmoidal graph) all fixed by F50 Heterozygosity lost by F33 (average heterozygosity) 100% assortative mating Genotype frequency quickly becomes homozygote dominated Allele frequency All fixed fro a single allele by F15 Heterozygosity Average lost by F4 Heterozygosity is lost under assortative mating. This is because heterozygotes are at a reproductive disadvantage as homozygotes will mate with like genotypes. Heterozygotes will not be produced by these matings either. Q 3.2) Results Population size 2000 (stand size), 100% assortative mating: Genotype frequency all homozygous by F4 Allele f fixed by F14 Heterozygosity average lost by F4 Population size 2000, 50% assortative mating Genotype f all homozygous by F25 Allele f all fixed by F29 Heterozygosity average lost by F25 Population size 250, 100% assortative mating Genotype f all homozygous by F4 Allele f all fixed by F12 Heterozygosity lost at F4 Population size 250, 50% assortative mating Genotype f all homozygous by F25 Allele f all fixed by F28 Heterozygosity lost at F25 Assortative mating dominates control of allele frequencies and the speed that alleles become fixed within a population compared with the effects of genetic drift (because the homozygotes are all mating with the same genotype and not with heterozygotes). Assortative mating is not dependant on carrying capacity. The size of the population is irrelevant when assortative mating is occurring. The results are similar for a high or a low population size. Catherine Carrick 200884273 Q 3.3) Method We conducted a series of experiments using disassortative mating and selected different levels of mating between 0% (random mating) and 100% (only unlike phenotypes mate). We then changed the population size from 2000 to 250 to see the effects of disassortative mating on genetic drift. Results Dissasortative mating shows that AA and aa will mate which increases heterozygosity and stabilises the population as shown in the results below: Population size 2000, 100% disassortative mating Geno (genotype frequency) heterozygote is predominant Allele (allele frequency) none become fixed. There is variation but it stays within 31% 68% variation Hetero (heterozygosity) increases in the first generation then remains constant Pop size 2000, 50% disassortative mating Geno predominantly heterozygote Allele none become fixed. There is less variation than with 100% disassortative mating. Variation is between 43% and 57% Hetero Increases in 1st generation and remains constant Pop size 250, 100% disassortative mating Geno -slight heterozygote increase Allele No fixed alleles. There is much greater variation than seen previously with a larger population size, between 21% and 79% Hetero increases in 1st generation then remains steady and begins to decrease. Remains above the initial percentage Pop size 250, 50% disassortative mating Geno heterozygosity increases steadily Allele No fixed alleles. Variation is less than with 100% disassortative mating and population size of 250. Variation levels out between 33% and 67% Hetero increases in the 1st generation and remains constant with a few small fluctuations which level back out Q 3.4) There would be more heterozygosity in the next generation when disassortative mating occurs and if this kind of mating is maintained, the effects of genetic drift occur much slower because the populations are prevented from diverging. Fig. 10 shows the comparison between disassortative mating and random mating where random mating allows genetic drift. Drift can still occur during dissasortative mating when the carrying capacity is very low. Catherine Carrick 200884273 Figure 10. (picture on left): Random mating, pop size 250 showing genetic drift acting to diverge allele frequencies. (picture on right): 50% dissassortative mating, population size 250 shows that dissasortative mating acts to counter genetic drift. Q 3.5) Method For this experiment we varied the initial genotype frequency for assortative and disassortative mating. We tried experiments where the initial allele frequency favoured one or the other allele. Fig. 11 show starting frequencies of 50/50% assortative mating. A small deviation in starting frequencies affects the final fixation percentages (Fig. 11). We did not include the brown allele in this experiment as the extra variable is not needed. Figure 11) Shows starting frequencies of 50/50% (50%-white allele, 50% black allele) with assortative mating = 100%. Small deviation in starting freq effects final fixation percentages. Catherine Carrick 200884273 Results Under dissassortative mating the time taken for equilibrium to establish is negatively correlated with the degree of deviation from a 1:1 starting allele ratio. Under assortative mating, fixation or loss of alleles is negatively correlated with the degree of deviation from a 1:1 starting allele ratio. Assignment 4: Modes of Natural Selection Q 4.1) Method In this experiment we investigated how fitness affects changes in allele frequency in the population. We began with default parameters except tree stand number (set at 100) and genotype frequencies. We changed the tree frequency to set up several experiments under conditions of directional selection for dark moths, directional selection for light moths, balancing selection favouring the brown moth, and diversifying selection favouring the dark and light moths. We tried experiments with the different conditions of selection and initial allele frequencies near zero and one. Results Directional selection for black moths where they tree frequencies are 50% black, 25% white and 25% brown trees gave the following results: Allele frequency becomes fixed rapidly by F10 (on average by F9) Genotype frequencies at F10 genotype becomes fixed for black allele In a small population, alleles become fixed more quickly but in larger populations allele frequencies are not affected as much. We kept the population size high so we would not see genetic drift in the experiment (4000 carrying capacity) with tree frequencies of 35%, 32% and 33%. Even the small amount of selection (35% black trees) shows fixation of alleles for the black morph of moth (Fig. 12). Selection for light moths gives the same results as selection for black moths. Figure 12. shows allele becoming fixed rapidly, due to a tiny increase in black trees on left, white trees on right (35 %) Catherine Carrick 200884273 Q 4.2) Starting figures are as follows: Black tree 25% Allele black 25% Brown tree 50% Allele brown 50% White tree 25% Allele white 25% After one generation, allele frequency remains stable (between 48% and 52%) and the genotype frequency becomes predominantly brown. This is because there is always the presence of black and white genotypes which cause slight variation. If you change the selection of trees to black 10%, white 10%, brown 80%, almost identical results occur (between 49% and 51% variation in allele frequency = stabilized). Q 4.3) To show diversifying selection we set the tree types to 45% black, 45% white and 10% brown. Genotype frequency by the 1st generation, there was a large decrease in brown morphs of moth and the equivalent increase in black and white morphs. This continues till F5 when the black morph became slightly more dominant (on average) due to random mating. The brown morph was phased out by F18 (on average) on most of the 100 tree stands. All alleles become fixed for either black or white by F23 (49% white, 51% black) (Fig 13). Figure 13. Shows 50% black and 50% white showing a 1:1 ratio Q 4.4) Small differences in fitness are effective in changing allele frequencies. Small differences in fitness have proportionally slower rates of allele frequency change compared with large differences in fitness. We conducted additional experiments with varying proportions of tree types. The results are as follows: (Where stand size = 4000, number of stands = 100, allele frequencies = white 20%, brown 60%, black 20%, tree frequencies = white 32%, brown 32%, black 36%). Even though there are a lower proportion of black alleles (A) to begin with, those alleles will have a higher fitness than white or brown as there is a higher percentage of black tree types. Over time this will equate to an increase in black morphs. There is, however, a Catherine Carrick 200884273 point where even if the black allele is fittest but there isnt a high enough population in the first place, it will crash and not recover. Q 4.5) Genetic variation is maintained under balancing selection because the allele frequencies remain stable. There is no fixation (presuming the all mating is random). The heterozygote allele is favoured and thus balances the homozygous allele. Assignment 5: Migration Q 5.1) Migration counteracts the effects of genetic drift. (Fig 14 and 15) Figure 14. Stand size of 500 and no migration shows heterozygosity varying over all populations. Green line = average heterozygosity over all populations. Figure 15. Shows stand size 500, and 8% migration. Shows migration maintains heterozygosity and there is less deviation from the average (green line) Catherine Carrick 200884273 Assignment 6: Population Bottlenecks Q 6.1) Disaster led to the loss of alleles and reduced heterozygosity. The more disasters there where, the more decreased the diversity became. (Fig 16, 17, 18) Figure 16. Control condition Shows low drift conferred by high population sizes (4000), all other variables adjusted to give Hardy-Weinberg equilibrium. Figure 17. Disaster parameters set to sometimes as opposed to never. Individual populations prone to fixation and loss of alleles. Catherine Carrick 200884273 Figure 18. Disaster frequency set to often rather than sometimes. Loss of diversity occurs faster than in figure 13 with most populations losing one or the other allele by generation 80. Q 6.2) Disaster increased the rate of extinction. The more regular the disaster, the more extinctions. Q 6.3) Migration moderated the effect that disasters had on the population. Discussion The results of our experiments clearly show that genetic drift effects smaller populations where heterozygoisity is lost rapidly and as the carrying capacity decreases, the risk of extinction increases. The is because the proportion of individuals with a certain phenotype within a small population are largely influenced by random variation in survival, and over time, the change in proportion of genotypes in subsequent generations leads to genetic drift. If one was to aim to conserve a hypothetical species, one would expect that because it is endangered, it would be a small population. To maintain genetic diversity among this species, one would need a large enough breeding population to begin with. Unfortunately, as is the case with most endangered species, populations become geographically isolated, mainly due to human disruption of habitat. Migration between breeding populations decreases and they become fragmented. Conservation efforts may be due to natural disasters such as tsunam is, fires etc, but are mainly to prevent the constant onslaught of human activities such as illegal logging in conservation areas. Figure 17 illustrates the effects of a bottleneck following a disaster, showing reduced variability (and a small population) leading to loss and/or fixation of alleles. As with genetic drift, the way to prevent population crashes, or rather soften the effects of bottlenecks, is to encourage migration among populations. This can be achieved by implementing the protection of corridors between known endangered populations. In theory, the populations can migrate between areas, maintaining a high enough level of breeding and genetic variation, to counter the effects of inbreeding depression or genetic drift (Fig 14 and 15). An example of how corridors may re-connect fragmented populations can be seen in Bhutans Jigme Singye Wangchuck National Park (www.panthera.org). Catherine Carrick 200884273 Figure 19. Map of known tiger populations (red) and proposed tiger corridors (orange). Data taken from www.panthera.org The proposed Eastern Himalayan corridor may help towards connecting isolated populations of tigers, and thus increasing genetic diversity (if these populations successfully reproduce with one another) (Fig 19). Random mating, as apposed to assortative mating, will increase heterozygosity and stabilise a population (Fig 10). This acts against genetic drift and stops the population form diverging as quickly. In a hypothetical situation then, you would preferably allow mating to occur naturally and at random. However, some conservation efforts include that of translocation of individuals or cross breeding certain individuals from separate populations. For this to be advantageous to the species, one must consider maintaining genetic diversity by genotyping the individuals before translocation. It would be senseless to swap or breed an AA individual with another AA individual from a separate population as this would lead to loss or fixation and not increase diversity. Our studies with B. betularia in question 4 to 4.5 show that intermediates are favoured over extreme phenotypes and that genetic variation is maintained under balancing (stabilizing) selection because the allele frequencies remain stable. There is no fixation (presuming the all mating is random). The heterozygote allele is favoured and thus balances the homozygous allele. As well as considering the genetic diversity of a species and its genealogy, one must understand the species by means of observations in the field including its behaviour. Later studies of B. betularia reinforced the need for such observations as it was found to rest high in the branches rather than on the trunks of trees as previously calculated. Also, modern science allowed for the study of its UV qualities which had otherwise been unaccounted for when considering levels of predation by birds. A close study of mating patterns should ideally be assessed to ensure the outcome of migration; corridors, translocation etc will be advantageous in terms of fitness. Catherine Carrick 200884273

Canadian Teenagers Essay -- Drugs and Alcohol, Cannabis, Marijuana

today's society Canadian teenagers are exposed to different pathway involving drugs. The most common drug used among Canadian teenagers is alcohol followed by cannabis.(Leslie, Karen 2008) Canadian teenagers are influenced by drugs and alcohol on a daily based at school and through the media. In Canada the legal drinking age is nineteen in most provinces with the exception of Quebec where it is eighteen years old. Teenagers who have family members with drug and alcohol problem or if they suffer from depression, anxiety or other various forms of mental health disorders are at a higher risk of developing and addiction or experimenting with drugs and alcohol.( Leslie, Karen 2008) . According to Leslie and Karen one in every five students will develop an alcohol dependency; it has an affect on their health, school and other problems. Students in the seventh and ninth grade indicated the average age for their first experience with alcohol is eleven years old (Leslie, Karen 2008). Alcohol intoxication comes along with great responsibilities. Adolescence are not mature enough to handle consequences and do not know the responsibilities thoroughly until they have experienced it. Alcohol plays a huge role in suicide and self-harm particularly among adolescence and young adults (Leslie, Karen 2008). The highest rate for adolescent patients is between the ages fifteen to nineteen years old who sustained unintentional injuries due to the presence of alcohol, which can also lead to violence among themselves (Leslie, Karen 2008). In Leslie and Karen research out of four hundred eight injuries involving violence 22.7 percent were involved in alcohol. Underage drinking can lead to unintentional fatal and non fatal injuries. The most common fat... ...ion during sex compared to females. During oral sex 44.4% of male’s claims to use condoms and 26.8% method only consisted of the female being on birth control. The smarter method using condoms and birth control during oral sex was only 8.1%. Leaving the most lack method, using no protection or any methods consisted 26.8% of males (Canadian Journal of Human Sexuality; 2006). The number of sexually active teens hasn't increased over the past two decades, the percentage of females having sex at a young age has. (Susan McClellan 2001). Having said, female parents disprove of teen pregnancy 56.8% of the time and males parents disprove 44 % of the time. Today in Canadian teen pregnancy and abortion rate are high, but Nunavut consists of the highest rates (McKay, Alexander). To get an abortion in Canada cost 400 dollars and it does not require permission from parents.

Comparing Brontes Wuthering Heights and Dickens Coketown Essay

Comparing Bronte's Wuthering Heights and Dickens Coketown      Ã‚   Throughout British Literature, compositions created by honored literary artists reflect current dominant lifestyles. The differences in prevailing environments are visible when comparing Emily Bronte's Withering Heights and Charles Dickens Coketown. Bronte reveals the wild unbinding freedom available though country living predominate in the late 17th and early 18th century, whereas Dickens explains the disheartening effects of industrialization, which caused massive urbanization and numerous negative consequences. Within both works, the authors portrayed the lifestyles their culture encouraged.    Rural households, spaced several miles apart, were common during Bronte's lifetime, therefore it is no surprise that she chose this enjoyable environment to set her scene for her novel which so closely mirrored her life. The moors surrounding Withering Heights remind each reader of the tranquil lifestyle enjoyed by the British at this juncture in their history. As pointed out in Seminar 1, "travel was not an easy chore" at this time, thus making frequent visiting among neighbors impossible (Seminar 1 J.H.). Therefore, it is understandable that women occupied their time knitting and gossiping (Seminar 1 K.T.). The women of Withering Heights portray this idol lifestyle. When Lockwood meets Cathy 2, she is idly setting in the apartment. Cathy 1 receives many tongue-lashings for her wild adventures in the moors as a girl. Later in her life, after her marriage to Edgar Linton, she realizes her position is to remain at the house and receive visitors there. These women represent the expecte d lifestyle of women during the romantic period.    Personal feelings an... ...hese terms infer the results of abandonment of faith and religion, vividly displaying the differences of the two periods.    Each author portrayed darkness of the soul in a separate way, just like the characteristics and origins of the darkness are separate. This turning from describing a revolting nature to a desecrated nature graphically describes the atmosphere in each period. Individual struggles dominated Bronte's time where societal hardships, resulting from technological and industrial advances, governed Dickens and his contemporaries.    Works Cited Damrosch, David, et al., ed.   The Longman Anthology of British Literature: Vol. B.   Compact ed.   New York: Longman - Addison Wesley Longman, 2000. Bronte, Emily.   Wuthering Heights. Norton Critical ed.   3rd ed.   Ed. William M. Sale, Jr., and Richard J. Dunn.   New York:   W. W. Norton, 1990.

Privacy :: Business Information Essays

Privacy Globalization is the tendency of businesses to spread throughout the world to offer their products and services. To reflect their global market presence, multi-national companies have adopted management models such as region-specific management, and product-specific management to maximize the potential to offer efficient products and services to their customers. One such management model that has been successful in the past few years is the business process outsourcing model. Businesses outsource processes such as back office operations and customer support services offshore. In some cases, these include access to personal information to a third-party agency leading to violation of personal information privacy. One may argue as to what constitutes personal information, as many theories of privacy exist. This paper addresses some noteworthy such theories. The paper also addresses ethical issues surrounding privacy of personal information in the context of business process outsourcing. Webster’s dictionary defines privacy as freedom from unauthorized intrusion. Alan Westin defines Privacy is the claim of individuals, groups, or institutions to determine for themselves when, how and to what extent information about them is communicated to others.1. Parent defines privacy as the condition in which others do not possess undocumented personal information.2 Lin and Loiu address the issue of privacy as undocumented personal knowledge.3 Privacy as Control of Information can be described as the information that can be made accessible to the public. The information that is available to the public is controlled by an individual. Any other information found about the individual other than that released by him can be considered as an invasion of the individual’s privacy.4 The meaning of what privacy is to an extent is driven by the society and its moral norms. Lin and Loui observe that reasonable expectations of privacy in public places must change as our social environment changes.5 As moral and social norms change in a society, the expectation from an individual towards society changes and thereby the individual’s privacy values. For example, slavery was an accepted practice in the late 19th century, today it’s not in practice. In the current information technology age, when an individual submits his personal information for purchasing merchandise online, it is within his expectation that his personal information be protected by the website. In future with the increasing use of technology in the day to day activities, new issues of privacy will arise making today’s notions of privacy out of date. One such issue is the privacy of personal information in business process outsourcing.

Victimology: Abuse

REVIEW SHEET FOR VICTIMOLOGY FINAL Any multimedia presentations post midterm Chapter 5 Dispute resolution Retributive justice vs. restorative justice Reintegrative shaming Victim-offender mediation Circle sentencing Problems and issues with restorative justice Chapter 8 Social constructionism Dr. Kempe Four obstacles that impeded the recognition of children as victims of abuse Forms of child abuse Harm standard Endangerment standard Mandatory reporterProcess of how calls are â€Å"screened in† or â€Å"screened out† Role of doctor-client privilege in detecting/reporting child abuse Central register Surveillance bias False positive vs. false negative error Parents anonymous Megan’s Law Kansas v. Hendricks Ex post facto Chapter 9 Gerontologist Rates of victimization for the elderly Fear-crime paradox Vicarious victimization Most common form of physical abuse in institutional settings Causes of institutional abuseRelationship between abusers and economic dependence on victims Types of abuse Chapter 10 Relationship between homicide and youthful AA males in the US Homicide victims are more likely to be? Ways to measure homicide Role of weapon involvement Nonprimary homicide Primary homicide Wolfgang Luckenbill’s situated transaction Mass media influence Regional culture of violence Golden hour Impact of medical resources Role of alcohol Death notification: stages The bereavement process Chapter 11 factors in routine activities perspective Workplace violence definition Media representations of workplace violence vs. reality Who is most at risk for workplace violence? Major causes of workplace victimization Third party lawsuits Victimization at junior and senior high schools Responses of students to real or perceived levels of school victimization Most juvenile crime happens during what times? Responses to school victimization Jeanne Clery Act Sexual harassment Quid pro quo Hostile environment