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The impact of pneumococcal conjugate vaccine on pneumococcal nasopharyngeal ecology in children 2 months through 5 yearsKhan, Tafaani 29 February 2024 (has links)
This study evaluates the ecology of Streptococcus pneumoniae (SP) nasopharynx (NP) colonization in response to the pneumococcal conjugate vaccines, specifically 7-Valent Pneumococcal Conjugate Vaccine (2000-2009), 13-Valent Pneumococcal Conjugate Vaccine (2010-2023) and 20-Valent Pneumococcal Conjugate Vaccine (2023-future date). It is anticipated that the replacement of PCV13 with PCV20, a pneumococcal conjugate vaccine with 7 additional polysaccharide conjugates to CRM197 will enhance the protection against non-vaccine serotypes which are in circulation in communities. The project will evaluate the dynamic changes in pneumococcal colonization over the 5-year time line from 2021-2026. Pneumococcal nasopharynx colonization is detected through nasopharyngeal culture and molecular techniques. The primary source of pneumococcal transmission occurs among the pediatric population and between children and adults. The impact of PCV7 and 13 on pneumococcal colonization over the prior 20 years created a herd effect that resulted in a reduction in pneumococcal disease in unimmunized children and adults. Studies of NP colonization has led to a deeper understanding of pneumococcal conjugate vaccine (PCV) effectiveness and the role of herd immunity in protecting the population, the emergence of replacement serotypes, the variation in invasive capability of each serotype and evolution of antimicrobial resistance resulting from the evolving ecology. In this 5-year-study, researchers at the Pelton Lab in Boston Medical Center set out to understand the prevalence of NP carriage of 13vPnC serotypes, the 7 unique 20vPnC serotypes and NVST (non-vaccine serotypes) within the pediatric population prior to and subsequent to the introduction of PCV 20 (Fall 2023).
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Vilka orsaker kan leda till aktieinvesterarnas irrationella beteende? : En empirisk studieTaskin, Yusuf, Gaballa Issa, Batoul January 2015 (has links)
Syfte: Syftet med studien är att förstå vilka orsaker som kan förklara svenska aktieinvesterares irrationalitet med hänsyn till deras informationsbearbetning. Metod: Undersökningen är genomförd av en kvantitativ forskningsmetod med inslag av kvalitativa aspekter i form av webbaserade enkäter. Enkäten är prestrukturerad då de flesta undersökningsfrågor är stängda men består även av öppna svarsalternativ. Enkäten publicerades på olika aktieforum samt sociala nätverk där studiens urval består av de medlemmar som valde att delta i undersökningen. Teori: Behavioral Finance ställs mot den effektiva marknadshypotesen och ligger till grund för undersökningen. Overconfidence, Herd Behavior och Egocentricity är de tre psykologiska faktorerna som studeras inom Behavioral Finance. Slutsats: Slutsatsen för Overconfidence är att män har mer övertro än kvinnor och anledningen till detta förklaras av deras bakgrund. Studien visar att orsakerna till förekomsten av Herd Behavior är bland annat att investerare säljer sina aktier när deras omgivning gör det, till följd av rädslan att deras omgivning vet något de inte vet samt att de inte vill hamna i en sämre sits om aktien går ner. Anledningen till att Egocentricity uppstår hos aktieinvesterare förklaras av att aktien de äger får ett högre värde hos deras sinnen, vilket gör att priset på aktien sällan känns tillfredsställande. Investerare agerar dessutom annorlunda beroende på vilka informationskällor de använder samt hur mycket tid de lägger ner på information. / Purpose: The purpose of this study is to understand the reasons that can explain Swedish stock investors irrationality with consideration to their information processing. Method: The survey was conducted using a quantitative research method with elements of qualitative aspects in form of web-based questionnaire. The survey was prestructured with closed survey questions, but also consists of open answers. The questionnaire was published on various websites for stock investors and social networks where the study sample consists of the members who chose to participate in the survey. Theory: Behavioral Finance contradicts The Efficient Market Hypothesis and sets the basis for this survey. Overconfidence, Herd Behavior and Egocentricity are the three psychological factors studied in Behavioral Finance. Conclusion: The conclusion of Overconfidence is that men are more overconfident than women, and the reason for this is explained by their backgrounds. The study shows that the causes for the occurrence of Herd Behavior include that investors sell their stocks when their surroundings do it, because of the fear that their surroundings knows something they don’t and they do not want to end up in a worse seat if the stock goes down. The reasons that Egocentricity occurs is explained by the stock they own gets a higher value in their minds, making the price of the stock rarely feeling satisfying. Investors also acts differently depending on which sources of information they use and how much time they devote to information.
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Pyskologin i aktiemarknaden : En studie om investeringsbeslutBotros, Marina, Marinkovic, Aleksandra January 2016 (has links)
Purpose: The purpose of the study is to examine how psychological factors affect shareholders and investors, and see which gender differences there are in their investment decisions. Method: The survey was based on a quantitative method with elements of qualitative aspects in form of a questionnaire. The questionnaire were answered by investors and shareholders at various websites for stock investor. The survey consisted of a total of 13 questions with both open and closed answers. Theory: The survey focused on four elements within behavioral finance. These factors are overconfidence, herd behavior, anchoring and familiarity bias. The efficient market hypothesis suggests full rationality which is the opposite of what behavioral finance advocates. Conclusion: Psychological factors affect investors and shareholders in their investment decisions. More men than women considered themselves to be better than average which indicates that they have a stronger overconfidence. In terms of herd behavior the respondents did not show that they follow the group when they have their own information, however, the opposite appeared when they had imperfect information. Women were affected by herd behavior more than men were. Women were affected more than men regarding familiarity bias. Anchoring also proved that the factor had an influence on the respondents but it was not a major difference between men and women.
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Analýza stáda a vlivů působících na reprodukční užitkovost prasnicMUŽÍKOVÁ, Martina January 2017 (has links)
The aim was selected in a commercial breeding (AGRO Vodňany a.s.) to analyze and evaluate herd reproductive performance of sows used for the production of piglets (final hybrids). The analysis was focused on the age structure of the sow, when the first and second litter was 28.8% on the 3rd to 5th litter 23.5% and the sixth and other litters of sows 47.7%.The annual renewal of the herd was culled 22.9% and 25.5% included sows for breeding.This breeding is used natural reproduction, where for the purposes of reproduction bred four boars lines of 48 (White paternity x Pietrain).The average gestation length breeding was 115.2 of days. In 2016, it was born an average of 13.8 piglet per litter, of which 11.5 piglet of live and been preserved was 10.2 piglet per litter.The length of the farrowing interval was 171,1 days and the onset of estrus after weaning piglets was an average of 4.9 days.Weaning is in monitored husbandry carried out between 28 to 31 day age of piglets.Part of this work was to evaluate zoohygiene also at stud and compared with the results of performance farms in the Czech Republic and recommendations for improving the results of husbandry evaluated. When comparing the results of selected indicators identified in Agro Vodňany a.s. with selected data published by the Czech Statistical Office for the South Bohemian Region and the Czech Republic in 2016, it was found that the number of piglets born per sow in the Czech Republic was 30.1 piglets. Piglets was born25.1 in South Bohemia and 24.3piglets was born per sow in Vodňany. The death of piglets from the number of births in the Czech Republic was 10.6% in the South Region accounted for 15.6% and in Vodňany it was 11.9%.The number of surviving piglets per sow in the Czech Republic was 26.9 piglets in South Bohemia have been preserved 21.3 piglet per sow and Vodnany during the reporting period have been preserved 21.4 piglets per sow.
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THE TRANSMISSION DYNAMICS OF EQUINE HERPESVIRUS TYPE 1 (EHV-1) INFECTION IN OUTBREAKS CHARACTERIZED PREDOMINATELY BY NEUROLOGIC OR RESPIRATORY ILLNESSMeade, Barry Jay 01 January 2012 (has links)
Formalized epidemiological field investigations were conducted to compare and contrast the transmission dynamics of EHV-1 neurological disease among horses stabled at Churchill Downs Racetrack, Louisville, Kentucky and of EHV-1 respiratory illness among horses stabled in the student barn at Murray State University. Differences were assessed by means of statistical and mathematical modeling techniques applied to survey and biological data collected over the course of the respective disease events.
Regression methods applied to survey data enabled the construction of a statistical model to predict a date of onset of illness for horses within each equine cohort. Comparisons of the epidemic curves revealed that the Murray State University outbreak was 4.5 times longer (9 weeks versus 14 days) than the Churchill Downs Racetrack event.
Survival analysis was used to explore the relationship between time to infection for each equine cohort. Horses stabled in the affected barn at Churchill Downs racetrack had a 3.02 times greater daily risk (p < 0.001) for contracting EHV-1 infection relative to horses stabled in the student barn at Murray State University.
Estimates of the basic R0 number, calculated using mathematical formulae that incorporated the duration of the infectious period for neuropathogenic and nonneuropathogenic strains of EHV-1, were 10.25 and 2.94 for the Churchill Downs racetrack and Murray State University outbreaks, respectively. The generation time for the Churchill Downs outbreak was 6.1 times shorter (0.39 days versus 2.38 days) than for the Murray State University event. An assessment of the temporal occurrence of symptomatic infection is similar for each event and suggests that the appearance of clinical illness is constant over the course of an outbreak.
A Reed-Frost model was constructed for each EHV-1 event where values of the transmission parameters (q, p and k) were estimated by fitting a model that most closely matched the observed profile of EHV-1 cases. The value of prophylactic vaccination on the spread of EHV-1 was assessed by making adjustments to these fitted models for varying levels of herd immunity. The results indicate that the prevention of EHV-1 neurological illness requires a higher level of herd immunity than EHV-1 respiratory illness.
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Interactions between avian colonial social structure and disease dynamicsWanelik, Klara January 2015 (has links)
All wildlife populations harbour parasites. However, seabirds are likely to play a particularly important role in the maintenance and dispersal of infectious agents as a result of their colonial breeding habits. Seabird colonies are also known to be highly spatially structured, but little is known about the effects of this spatial structuring on seabird parasite dynamics. In this thesis, I use a tick-borne virus, Great Island virus (GIV), found in a large common guillemot (Uria aalge) colony bordering the North Sea as a model system to explore this relationship. I use a multidisciplinary approach, framed by a simple epidemiological model of the guillemot-tick-virus system. In Chapter 2, I describe a novel epidemiological model and parameterise it using the existing literature. The model suggests the importance of spatial structure within the guillemot colony, but also identifies a key missing parameter, the rate of virus transmission between pre-breeding and breeding areas. In Chapter 3, I go on to test the potential role of independent tick movement in driving transmission between these two areas, by quantifying the mobility of host-seeking seabird ticks, Ixodes uriae. I show the potential for ticks to walk ranges described anecdotally in the literature, in just a few minutes, but stress the importance of further experiments in the field. Chapter 4, I test the potential role of guillemot-mediated tick movement between pre-breeding and breeding areas. I show that pre-breeding guillemots spend a limited proportion of time ashore during daylight hours, which increases significantly as the season progresses and varies between individuals. A similar pattern is observed when considering how often they enter breeding areas when ashore; generally infrequently but varying spatiotemporally and between individuals. In Chapter 5, I apply finite mixture modelling techniques to improve existing estimates of age- and strain-specific GIV seroprevalence and force of infection in the guillemot colony. I also provide the first estimates of these parameters for eight strains, and highlight the importance of understanding strain-specific differences in GIV dynamics in future studies. Finally, I bring all four data chapters together in Chapter 6, by inputting my new parameter estimates (Chapters 3-5) into my existing model (Chapter 2). Taken together, my results suggest that GIV transmission within the guillemot colony may increase in the future as a result of declining breeding abundance and success, with more frequent or extreme disruption leading to a higher risk of infection within the colony. More generally, my results suggest that seabird colonies can be highly sensitive to changes in their spatial structure, and that endemic parasites have the potential to substantially impact, and hence to be an added threat to, their seabird hosts.
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The association between calfhood BRDC and subsequent departure from the herd, milk production, and reproduction: an observational, retrospective studySchaffer, Aaron P. January 1900 (has links)
Master of Science / Department of Clinical Sciences / Daniel U. Thomson / Bovine respiratory disease (BRDC) is a multifaceted disease that causes considerable economic loss in both the beef and dairy industry. However, because there may be lingering effects of BRDC in the dairy industry, the full economic costs of the disease may not be realized. These lingering effects may include an increased departure from the herd, decreased milk production, and decreased reproductive performance. All of these outcomes are affected by multiple variables, but proper statistical modeling can control for many of the different influences. Few studies have attempted to look at the long term effects of calfhood BRDC but consistent associations have not been identified. The objective of this observational, retrospective study was to determine the association between calfhood BRDC prior to 120 d of age and departure from the herd, milk production, and reproductive performance. The association between the occurrence of BRDC with departure from the herd prior to first calving depended on the birth year, but for 5 of the 6 years, animals that contracted BRDC were 1.62 to 4.98 times more likely to leave the herd than animals that did not contract BRDC. In addition, animals that contracted BRDC were also 1.28 times more likely to leave the herd between first and second calving than animals that did not contract BRDC. Furthermore, the age at BRDC occurrence was associated with departure from the herd. Animals that contracted BRDC pre-weaning were 2.62 times more likely to leave the herd prior to first calving than animals that contracted BRDC post-weaning. However, age of BRDC occurrence was not significantly associated with departure from the herd between first and second calving. The occurrence of BRDC during the first 120 d of life was associated with a 233 kg decrease in lactation-one production, but was not significantly associated with production in subsequent lactations. Finally, calfhood BRDC was not significantly associated with a decreased reproductive performance measured by calving interval. In conclusion, calfhood BRDC negatively impacts productivity both prior to and after first calving.
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A Management Study of the Idaho-Utah Interstate Deer Herd With Special Reference to the Sublett, Black Pine, and East Raft River Mountain UnitDiem, Kenneth L. 01 May 1952 (has links)
Extensive deer migrations have been observed for many, years in western mountain regions. More recently several complex interstate migrations have become the objects of careful study and the subjects of special wildlife movement programs. The interstate deer migrations between the Sublett-Black Pine, Idaho, areas and the East Raft River Mountain, Utah, area are not exceptional. These migrations are now of such a magnitude that they are creating management problems of increasing importance to the 2 states involved.
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Reproduction and Hematology of the Cache Elk HerdFollis, Thomas B. 01 May 1972 (has links)
The initial three years of a 10-year reproductive study of elk involved three major phases. A fourth was added because of convenience. Objective 1 was to ascertain pregnancy rates in yearling and mature elk by rectal palpation, associate these rates with subsequent fall cow/calf ratios, and to test concurrently an ultrasonic fetal heart detector. Rectally observed anatomical changes in gravid uteri of cattle were directly applicable to elk. Ultrasonic detections of pregnancies in elk and deer were unsuccessful.
Pregnancy rates in the 1969-70 winter of 100 and 0 percent, respectively, for 19 adult and five yearling elk were associated with subsequent pre- and post-season cow/calf ratios of 100/55 and 100/68. Pregnancy rates the next winter of 82 and 17 percent, respectively, for 60 adults and 23 yearlings resulted in pre- and post-season cow/calf ratios of 100/52 and 100/39. Pregnancy rates in the 1971-72 winter were 82 and eight percent, respectively, for 39 adults and 13 yearlings; compilation of data for the first three years of the study precluded inclusion of associated fall and winter cow/calf ratios.
Objective 2 was to determine the breeding efficiency of yearling male elk. Pregnancy rates were 86 and 93 percent, respectively, in 14 yearling-bred cows and 15 adult-bred cows in 1971. Rectal palpations revealed eight of 12 conceived in October from yearling breeding and 10 of 14 in September from adult breeding.
A peak in yearling breeding was estimated to have occurred between October 11 and October 25, as compared to two peaks in adult breeding estimated near September 5 and September 20, The earliest and latest conceptions were estimated near October 5 and November 21, and September 5 and November 3, respectively, in yearling and adult bred cows. Most wild and captive yearlings polished or began peeling their antlers about October 1. compared to August 15 for captive adults.
Data suggested recrudescent testicular tissues had initiated a rise in blood androgen, which coincided with a peak in breeding activity in September and October.
lnducement of twin births in Objective 3 was attempted via synchronized superovulations during the September rut in 1970. Progestogen implants were used from 14 to 20 days to synchronize elk in two pre-rut trials and one mid-rut trial.
Follicle-stimulating hormone (FSH) suspended in carboxy-methyl-cellulose (CMC), injected (intramuscular) coincident with implant removal was judged superior to pregnant mares serum (PMS) alone or FSH in peanut oil. Injections of FSH in anestrous elk produced a mean of 2.4 follicles and corpora lutea (CL) (2.0 follicles and 1.33 CL), the first week, and PMS produced a mean of 9.67 follicles and CL (8.67 follicles and 1.5 CL) response was low in a pre-rut trial with two levels of FSH in peanut oil.
No conceptions apparently occurred in two groups of six cows injected with 15 and 20 milligrams FSH. Nine of 12 adults (including three of four controls) and none of four remaining yearlings were estimated to have conceived between September 30 and October 15 (five to 20 days after the treatment period), Two additional yearlings were superovulated with FSH without synchronization, but did not conceive.
Data presented from blood analyses in Objective 4 included mean values for free-ranging mature elk (probability value indicates a significant difference between free-ranging and captive mature elk). The values were: total leucocytes (WBC), 6160/cubic millimeter (cu mm); WBC differential (percent)--neutrophils (44), lymphocytes (48, P < .05), monocytes (1), eosinophils (7), and basophils (0.1, P< .01); erythrocytes, 11 million/cu mm; hemoglobin, 21 grams/100 milliliters (g%), (P< .01); packed cell volume, 53 percent; blood urea nitrogen, 36 Sigma units (P< .01); serum glutamic-oxalacetic transaminase, 91 Units; lactic dehydrogenase, 863 Units; alkaline phosphatase, 2.22 Sigma units (P < .01); total protein, 7.0 g% (P < .01); albumin, 3.8 g% (P < .05); globulin fractions (g%)--alpha1 (A4), alpha2 (.6) beta (.95), and gamma (1.98); glucose, 183 milligrams/100 milliliters (mg%), (P < .05); creatinine, 2.9 mg%; uric acid, 0.39 mg%; cholesterol, 80.5 mg%; total bilirubin, 0.65 mg%; inorganic phosphorous, 3.4 mg%; and calcium ion, 9.2 mg%. Serology for Brucella abortus and Leptos pira pomona was negative.
Blood values from five big game species and three species of domestic animals are presented for comparison. Significant differences in sampled elk were noted (P < .01 or < .05) in various tests between sexes, reproductive status, free-ranging and captive at different ages, and serial four-hour samples. A significant difference (P < .10) was noted in progestogen assays for non-pregnant and pregnant elk. Captive elk were positive and free-ranging were negative for Dictyocaulus infestations, Yearling and adult male reproductive tracts were microscopically differentiated. Nutritional conditions of experimental elk were considered excellent when fed a special pelleted formula freechoice with grass hay.
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Browse Evaluation and Survey Techniques for the Uinta North Slope Moose HerdBabcock, William H. 01 May 1977 (has links)
A study was conducted on the North Slope of the Uinta Mountains from January, 1972 through June, 1974, to determine the effects of three simulated levels of moose utilization on the crude protein content, phosphorus content, digestibility and vigor of willow plants. A comparison was also made on the crude protein content, phosphorus content and digestibility of current year's versus past years' willow growth. Finally, the validity of direct and indirect population enumeration methods was compared for the possible development of a standardized moose survey technique.
Clipping caused a highly significant increase in crude protein and phosphorus content between treatment levels. There was also a highly significant increase in digestibility between years. Plant vigor comparisons were confounded by additional sources of mortality and the effects of environmental variables.
A comparison of the nutrient content and digestibility of 1 t o 5 year-old willow growth showed that crude protein content, phosphor us content and digestibility decreased with increasing twig age. Additional factors are discussed which indicate that the carrying capacity of the winter range is larger than previously described.
A poor correlation was found be tween direct aerial moose observations and indirect population estimates from pellet-group counts.
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