1,152 research outputs found

    100 years of tropical bryophyte and lichen ecology : a bibliographic guide to the literature from 1901 - 2000

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    A list of 401 citations pertaining to the ecology of tropical bryophytes and lichens is presented. The bibliography includes publications addressing the biology, ecology, natural history, and physiology of bryophytes and lichens, but generally eschews taxonomic and floristic papers. All citations have been verified, unless denoted with an asterisk (*). An appendix that groups citations by category is provided

    Nonexistence results for the Korteweg-deVries and Kadomtsev-Petviashvili equations

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    We study characteristic Cauchy problems for the Korteweg-deVries (KdV) equation ut=uux+uxxxu_t=uu_x+u_{xxx}, and the Kadomtsev-Petviashvili (KP) equation uyy=(uxxx+uux+ut)xu_{yy}=\bigl(u_{xxx}+uu_x+u_t\bigr)_x with holomorphic initial data possessing nonnegative Taylor coefficients around the origin. For the KdV equation with initial value u(0,x)=u0(x)u(0,x)=u_0(x), we show that there is no solution holomorphic in any neighbourhood of (t,x)=(0,0)(t,x)=(0,0) in C2{\mathbb C}^2 unless u0(x)=a0+a1xu_0(x)=a_0+a_1x. This also furnishes a nonexistence result for a class of yy-independent solutions of the KP equation. We extend this to yy-dependent cases by considering initial values given at y=0y=0, u(t,x,0)=u0(x,t)u(t,x,0)=u_0(x,t), uy(t,x,0)=u1(x,t)u_y(t,x,0)=u_1(x,t), where the Taylor coefficients of u0u_0 and u1u_1 around t=0t=0, x=0x=0 are assumed nonnegative. We prove that there is no holomorphic solution around the origin in C3{\mathbb C}^3 unless u0u_0 and u1u_1 are polynomials of degree 2 or lower.Comment: 17 pages in LaTeX2e, to appear in Stud. Appl. Mat

    A Comparison of Sociodemographic Correlates of Cigarette, Alcohol, and Energy Drink Consumption among High School Students in the United States, 2010-2015

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    OBJECTIVE: Despite growing awareness about the harmful physiological effects of energy drinks, especially among young people, there is little regulation governing the marketing and sale of these products to adolescents. Thus, in contrast to substances such as cigarettes and alcohol, energy drinks are readily available to adolescents, and widely consumed. It is not known if the easy availability of energy drinks has the effect of increasing usage of these substances among adolescents, and reducing sociodemographic differences in the consumption of energy drinks. In this study, we use pooled data (2010-2015) from the nationally representative Monitoring the Future survey (n=43,283), to compare consumption of energy drinks with other substance use, and to compare the sociodemographic correlates of energy drink consumption among high school students (10th and 12th grade) with those of cigarette and alcohol consumption. METHODS: Covariate-adjusted estimates for prevalence of consumption of energy drinks, cigarettes, and alcohol for each of different sociodemographic strata were obtained via logistic regression analysis. Additional analyses examined the extent to which socioeconomic disparities in prevalence of consumption of energy drinks are predicated by cigarette smoking and alcohol use. RESULTS: While the patterning of differences in energy drink use by sex, grade, race and parental education (as a measure of socioeconomic status) were similar to those seen in cigarette smoking and ever-use of alcohol, the magnitude of differences across subgroups varied across these behaviors. Racial/ethnic, socioeconomic and age differences were smaller in the case of energy drink use compared to alcohol or cigarette use. Gender differences were larger than in the case of cigarette smoking. In all cases, energy drink use were higher among students who were current users of alcohol or cigarettes, but there was little evidence that sociodemographic variables were differentially associated with energy drink use within these strata. CONCLUSIONS: Ready availability of energy drinks has resulted in elevated use of these products relative to cigarette smoking and alcohol, and some narrowing of socioeconomic differentials in use. Regardless of socioeconomic status, use of energy drinks is higher among current users of cigarettes and / or alcohol

    Epiphytic bryophytes of Monteverde, Costa Rica

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    A survey of the literature and collections in the Monteverde Cloud Forest Preserve and adjacent pastureland yielded a total of 198 epiphytic bryophyte taxa (120 species of hepatics in 50 genera, 77 species of moss in 48 genera, and 1 hornwort): 178 in the primary forest, 63 in the secondary forest, and 84 in the pastureland

    On Optimal and Fair Service Allocation in Mobile Cloud Computing

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    This paper studies the optimal and fair service allocation for a variety of mobile applications (single or group and collaborative mobile applications) in mobile cloud computing. We exploit the observation that using tiered clouds, i.e. clouds at multiple levels (local and public) can increase the performance and scalability of mobile applications. We proposed a novel framework to model mobile applications as a location-time workflows (LTW) of tasks; here users mobility patterns are translated to mobile service usage patterns. We show that an optimal mapping of LTWs to tiered cloud resources considering multiple QoS goals such application delay, device power consumption and user cost/price is an NP-hard problem for both single and group-based applications. We propose an efficient heuristic algorithm called MuSIC that is able to perform well (73% of optimal, 30% better than simple strategies), and scale well to a large number of users while ensuring high mobile application QoS. We evaluate MuSIC and the 2-tier mobile cloud approach via implementation (on real world clouds) and extensive simulations using rich mobile applications like intensive signal processing, video streaming and multimedia file sharing applications. Our experimental and simulation results indicate that MuSIC supports scalable operation (100+ concurrent users executing complex workflows) while improving QoS. We observe about 25% lower delays and power (under fixed price constraints) and about 35% decrease in price (considering fixed delay) in comparison to only using the public cloud. Our studies also show that MuSIC performs quite well under different mobility patterns, e.g. random waypoint and Manhattan models

    Assessment of Methylprednisolone Purging Efficacy on Daudi Burkitt Lymphoma Cells from Normal Bone Marrow

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    Studies on normal bone marrow and Daudi Burkitt lymphoma cells were performed to determine the efficacy of selective, in vitro chemopurging with methylprednisolone (MP). We found that MP reduces the numher of lymphoma cells without significant damage to bone marrow cells. This information is important because we need to improve the existing in vitro purging regimens used to cleanse autologous marrows of metastatic disease before transplantation into cancer patients who have received high-dose chemotherapy. Normal human bone marrow (NBM) and Daudi lymphoma cells were trealed in parallel with various purging regimens. NBM death was evaluated using soft-agar culture, while Daudi cell death was evaluated using one-week liquid culture. A protocol of 2.0 mg/mL of MP for four hours demonstrated optimal selectivity. When treatment was followed by cryopreservation, a 1.7 log purge of Daudi cells was increased to 2.3 logs while preserving 36% of committed NBM precursors. We repeated these experiments on a simulated contaminated marrow to model closely the mixture of normal and malignant cells found in advanced, metastatic disease. We evaluated this mixed system by flow cytometric immunoanalysis using the two-color CD10/CD20 markers to detect residual, viable Daudi cells. Our initial results were reproducible in this mixed-cell system, further supporting the evidence for effective in vitro purging of bone marrow using MP

    EVALUATION OF SERUM-FREE IRON AND GLYCATED HEMOGLOBIN IN UNCONTROLLED TYPE-II DIABETIC PATIENTS

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    Objective: Diabetes mellitus (DM) is a common health problem in the world. Free iron may contribute to the pathogenesis and progress of this disease and its complication. Iron causes hyperinsulinemia by decreasing the insulin uptake and metabolism by hepatocytes. Elevated iron stores are commonly found in insulin resistance. Iron in its free form is known to induce oxidation of biomolecules by producing harmful hydroxyl radicals. In this study, we aimed to estimate and compare the serum levels of free iron in diabetes and healthy individuals.Methods: This study included 244 subjects in two groups. Group-I comprised 204 subjects with DM and Group-II comprised 40 healthy subjects. Blood sugar, free iron, and glycated hemoglobin were analyzed in blood samples using standard kits. The results of all the parameters were expressed as mean±standard deviation. Student t-test was done to assess the statistical significance between two groups. The association between the parameters was studied by Pearson correlation.Results: In this study, we found a significant increase in serum free iron in Group-I (p<0.01) when compared with Group-II. A significant correlation between the serum free iron and glycated hemoglobin (r=0.59; p<0.001) and fasting blood sugar (r=0.43; p<0.001).Conclusion: The elevated serum free iron in uncontrolled diabetes may contribute to oxidative stress which may be associated with complications of diabetes.Keywords: Free iron, Glycated hemoglobin, Hyperinsulinemia, Diabetes mellitus

    Monteverde: Ecology and Conservation of a Tropical Cloud Forest - 2014 Updated Chapters

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    The Monteverde Cloud Forest Reserve has captured the worldwide attention of biologists, conservationists, and ecologists and has been the setting for extensive investigation over the past 40 years. Roughly 40,000 ecotourists visit the Cloud Forest each year, and it is often considered the archetypal high-altitude rain forest. “Monteverde: Ecology and Conservation of a Tropical Cloud Forest”, edited by Nalini Nadkarni and Nathaniel T. Wheelwright (Oxford University Press, 2000 and Bowdoin’s Scholar’s Bookshelf. Book 1 ), features synthetic chapters and specific accounts written by more than 100 biologist and local residents, presenting in a single volume everything known in 2000 about the biological diversity of Monteverde, Costa Rica, and how to protect it. The new short chapters written in 2014 by original contributors, and presented here update and expand that knowledge through 2014.https://digitalcommons.bowdoin.edu/scholars-bookshelf/1004/thumbnail.jp

    Blood Glucose Regulation Using Labview

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    Diabetes mellitus (DM), commonly referred to as diabetes, is a group of metabolic diseases in which there are high blood sugar levels over a prolonged period. If not regulate the glucose level then it will cause the serious damage to heart, kidneys, eyes, and nerves. The pancreas produces insulin to absorb the glucose. In type I diabetes the pancreas does not secrete insulin to compensate this artificial pancreas will be used. The artificial pancreas will mimic the function of pancreas it consists of a sensor, controller and insulin pump. The sensor continuously monitors glucose, the amount of insulin required will be calculated using a controller then injected using insulin pump this is the function of the artificial pancreas. The food we take is converted into glucose. So, meal intake will greatly affect the glucose levels, in this paper a closed loop model is developed based on Bergman\u27s minimal model and meal intake is introduced as a disturbance then the control action is performed using Fuzzy and PID controller using LABVIEW software.  So, from this, if the glucose concentration exceeds/decreases, above/below a certain point necessary control action will be taken

    Maternal mortality in a tertiary care hospital: a 3-year retrospective study

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    Background: Systematic review to determine the epidemiological aspects and causes of maternal mortality there by exploring possibility of intervention and implementing Evidence-based health policies and programmes to prevent future maternal death. Aims and objectives of the study were to calculate the maternal mortality rate in our hospital, to assess the epidemiological aspects of maternal mortality, to assess the type of delay and causes of maternal mortality and to suggest ways to reduce the MMR.Methods: This is a 3-year retrospective study from January 2017 to December 2019 that will be conducted in the department of obstetrics and gynaecology, The Apollo medical college and District hospital, Chittoor a tertiary care teaching hospital situated in the southernmost part of Andhra Pradesh state in India. It gets a large number of referrals from PHCs, CHCs, and maternity homes as well as from hospitals across Chittoor district. Epidemiological data will be collected from the hospital register. Maternal mortality ratio, epidemiological factors and causes affecting maternal mortality are assessed.Results: MMR in present study was 66 per 1,00,000 live births. Women in the age group of 20 to 30 years (85.72%), illiteracy (57.16%) and low socioeconomic status (100%) were risk factors for maternal mortality. Obstetric haemorrhage (57.16%) is most common cause whereas type 1 and type 2 delays are most common contributing factors for maternal mortality.Conclusions: Early identification and management of pregnancy complication, strengthening of existing Emergency obstetric care (EmOC) facilities, easy transport and appropriate referral linkages are keys to reduce maternal mortality to further extent
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