Parallel latitudinal clines to the long-standing ones in the original Palearctic populations have independently evolved at different rates for chromosomal polymorphism and body size in South and North American populations of Drosophila subobscura since colonization around 25 years ago. This strongly suggests that (micro) evolutionary changes are largely predictable, but the underlying mechanisms are unknown. The putative role of temperature per se was investigated by using three sets of populations at each of three temperatures (13 degrees , 18 degrees , and 22 degrees C) spanning much of the tolerable range for this species. We found a lower chromosomal diversity at the warmest temperature; a quick and consistent shift in gene arrangement frequencies in response to temperature; an evolutionary decrease in wing size, mediated by both cell area and cell number, at 18 degrees C; no relationship between wing size and those inversions involved in latitudinal clines; and a shortening of the basal length of longitudinal vein IV relative to its total length with increasing standard dose. The trends for chromosomal polymorphism and body size were generally inconsistent from simple climatic-based explanations of worldwide latitudinal patterns. The findings are discussed in the light of available information on D. subobscura and results from earlier thermal selection experiments with various Drosophila species.

The paper proposes a simple, new, analytical framework for assessing the cost and benefits of macroprudential policies. It proposes a measure of net benefits in terms of parameters that can be estimated: the probability of crisis, the loss in output given crisis, policy effectiveness in bringing down both the probability and damage during crisis, and the output-cost of a policy decision. It discusses three types of policy leakages and identifies instruments that could best minimize the leakages. Some rules of thumb for policymakers are provided.

The standard prophylactic regimen used as antiretroviral therapy (ART) for infants born to mothers in high-income and middle-income countries who are infected with human immunodeficiency virus (HIV) infection has been a 6-week course of zidovudine.Randomized controlled trials investigating postexposure prophylaxis for infants born to late-presenting women infected with HIV who did not receive ART in pregnancy have been conducted in breast-fed populations but not in nonYbreast-fed populations. Several trials showed that prophylaxis with combination ART (zidovudine plus Q1 antiretroviral drugs) was effective in reducing viral transmission in high-risk breast-fed populations in low-income countries. However, it is unclear whether prophylaxis with combination ART would prevent intrapartum HIV-1 transmission in nonYbreast-fed infants of women who had not received antenatal ART.This randomized controlled study compared the efficacy and safety of ART prophylactic regimens in a population of solely formula-fed infants whose mothers had not received ART during pregnancy. In designing the study, the authors hypothesized that a 3-drug ART regimen would confer a higher level of protection against intrapartum HIV transmission than a 2-drug regimen. Both regimens were evaluated in this study. Formula-fed infants exposed to HIV-1 were randomly assigned to 1 of 3 ART regimens within 48 hours after birth. Infants in each of the 3 groups received zidovudine for 6 weeks. The first group was given only zidovudine (zidovudine-alone group, n = 566). In addition to zidovudine, the second group received 3 doses of nevirapine during the first 8 days of life (2-drug group, n = 562). The third group received zidovudine plus nelfinavir and lamivudine for 2 weeks (3-drug group, n = 556). The primary study outcome was HIV-1 infection at 3 months of age among infants uninfected at birth. The Kaplan-Meier method was used to estimate transmission rates.The study population included 1684 infants enrolled between 2004 and 2010 at 17 sites in Brazil, Argentina, the United States, and South Africa. The overall rate of in utero transmission of HIV-1 was 5.7% (93 infants); there were no significant differences among the groups. At 3 months, the overall rate of intrapartum transmission was 3.2%. Compared with the zidovudine-alone group, intrapartum transmission at 3 months was reduced by half in the 2-and 3-drug groups: The rate was 4.8% (24 infants) in the zidovudine-alone group versus 2.2% (11 infants) in the 2-drug group and 2.4% Infectious Disease 612

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The approach presented is promising as a simple and efficient method for first-tier, marker-assisted screening of environment-specific B.t. germplasm effective in controlling a single target pest.

Growth and yield of cabbage depending on nitrogen ratesThe appropriate program of fertilization for the cabbage crop can be obtained through the synchronization of the plant demand of the plant with the supply of N during the cycle. We determined the influence of rates of nitrogen in the accumulation of dry weight and in the yield, in different phases of the development of cabbage hybrid Shutoku. The experiment was carried out in EPAMIG, Oratorios, Minas Gerais State, Brazil, from July 2 th to October 10 th , 2008. Five rates of N were evaluated (0, 75, 150, 300 and 450 kg ha -1 ). Each treatment was set in randomized block design with four replications. At 50, 64 and 78 days after seeding, the characteristics of growth of the plants, length of the stem, number of leaves, fresh and dry weight of leaves, stems and roots and N content in the dry weight were measured. The harvest occurred at 103 days after seeding. The highest production of cabbage head fresh weight was of 1.13 kg obtained with the rate of 277.8 kg N ha -1 . With the optimal rate of N for the yield, the optimal estimated values for the content of N-NO 3 in leaves and of total nitrogen varied with the sampling time. The initial period of the highest accumulation of dry weight varied with the rates of nitrogen.

Background: In Brazil, mathematical models for deriving estimates and projections of COVID-19 cases have been developed without data on asymptomatic SARS-CoV-2 infection. We estimated the seroprevalence of antibodies to SARS-CoV-2 among blood donors in the State of Rio de Janeiro. Methods: Data were collected on 2,857 blood donors from April 14 to 27, 2020. We report the crude prevalence of antibodies to SARS-CoV-2, the weighted prevalence by the total state population, and adjusted prevalence estimates for test sensitivity and specificity. To establish the correlates of SARS-CoV-2 prevalence, we used logistic regression models. The analysis included period and site of blood collection, sociodemographic characteristics, and place of residence. Results: The proportion of SARS-Cov-2 positive tests without any adjustment was 4.0% (95% CI 3.3-4.7%), and the weighted prevalence was 3.8% (95% CI 3.1-4.5%). Further adjustment by test sensitivity and specificity produced lower estimates, 3.6% (95% CI 2.7-4.4%) and 3.3% (95% CI 2.6-4.1%), respectively. The variable most significantly associated with the crude prevalence was the period of blood collection: the later the period, the higher the prevalence. Regarding socio-demographic characteristics, the younger the blood donors, the higher the prevalence, and the lower the educational level, the higher the odds of a positive SARS-Cov-2 antibody. Similar results were found for the weighted prevalence. Discussion: Although our findings resulted from a convenience sample, they match some basic premises: the increasing trend over time, since the epidemic curve in the state is still on the rise; the higher prevalence among the youngest who are more likely to circulate; and the higher prevalence among the less educated as they have more difficulties in following the social distancing recommendations. Despite the study limitations, it is possible to infer that protective levels of natural herd immunity to SARS-CoV-2 are far from being reached in Rio de Janeiro.

We have previously reported that acute blood volume expansion in awake rats delays the gastric emptying of a liquid meal, using the phenol red method. In this study we attempted to investigate the neural mechanisms involved in this phenomenon. Blood volume expansion, due to Ringer-bicarbonate infusion up to a volume equivalent to 5% of body weight, decreased the gastric emptying of a liquid meal by half (38.2 +/- 1.8 vs 18.7 +/- 3.2%, P < 0.05). The blood volume expansion effect on gastric emptying of liquid was prevented by separate pretreatments, consisting of subdiaphragmatic vagotomy or i.v. injection of hexamethonium (20 mg kg-1) or yohimbine (3 mg kg-1). Intravenous injection of atropine (0.5 mg kg-1), guanethidine (10 mg kg-1), L-NAME (3 mg kg-1), prazosin (1 mg kg-1) or propranolol (2 mg kg-1) did not prevent the blood volume expansion effect on gastric emptying. Bilateral adrenalectomy or coeliac ganglionectomy were also ineffective. The results indicate that blood volume expansion decreases gastric emptying of liquid through vagal-dependent pathways, sensitive to hexamethonium and yohimbine. Evidence for the participation of the peripheral sympathetic nervous system was not found.