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Several studies have shown that the Brazilian Northeast is a region with high rates of inbreeding as well as a high incidence of autosomal recessive diseases. The elaboration of public health policies focused on the epidemiological surveillance of congenital anomalies and rare genetic diseases in this region is urgently needed. However, the vast territory, socio-demographic heterogeneity, economic difficulties and low number of professionals with expertise in medical genetics make strategic planning a challenging task. Surnames can be compared to a genetic system with multiple neutral alleles and allow some approximation of population structure. Here, surname analysis of more than 37 million people was combined with health and socio-demographic indicators covering all 1794 municipalities of the nine states of the region. The data distribution showed a heterogeneous spatial pattern (Global Moran Index, GMI = 0.58; p < 0.001), with higher isonymy rates in the east of the region and the highest rates in the Quilombo dos Palmares region – the largest conglomerate of escaped slaves in Latin America. A positive correlation was found between the isonymy index and the frequency of live births with congenital anomalies (r = 0.268; p < 0.001), and the two indicators were spatially correlated (GMI = 0.50; p < 0.001). With this approach, quantitative information on the genetic structure of the Brazilian Northeast population was obtained, which may represent an economical and useful tool for decision-making in the medical field.
The European conquest and colonization of the Caribbean precipitated massive changes in indigenous cultures and societies of the region. One of the earliest changes was the introduction of new plant and animal foods and culinary traditions. This study presents the first archaeological reconstruction of indigenous diets and foodways in the Caribbean spanning the historical divide of 1492. We use multiple isotope datasets to reconstruct these diets and investigate the potential relationships between dietary and mobility patterns at multiple scales. Dietary patterns are assessed by isotope analyses of different skeletal elements from the archaeological skeletal population of El Chorro de Maíta, Cuba. This approach integrates carbon and nitrogen isotope analyses of bone and dentine collagen with carbon and oxygen isotope analyses of bone and enamel apatite. The isotope results document extreme intrapopulation dietary heterogeneity but few systematic differences in diet between demographic/social groups. Comparisons with published isotope data from other precolonial and colonial period populations in the Caribbean indicate distinct dietary and subsistence practices at El Chorro de Maíta. The majority of the local population consumed more animal protein resources than other indigenous populations in the Caribbean, and their overall dietary patterns are more similar to colonial period enslaved populations than to indigenous ones.
In the wake of George Floyd's killing by police in Minneapolis and the global response inspired by Black Lives Matter, it is time for the field of global mental health to reexamine how we have acknowledged and addressed racism in our institutions, our research, and our mental health services. In solidarity with street level responses, this is an important opportunity to understand and collaboratively respond to public demand for systemic change. To respond effectively, it is vital to (1) be aware of the colonial history that influences today's practices, and move forward with anti-colonial and anti-racist actions; (2) identify where and why diversity and representation are lacking in the global mental health workforce, then follow steps to combat these disparities; and (3) work with communities and institutions to end both police violence and structural violence.
Starting in 2016, we initiated a pilot tele-antibiotic stewardship program at 2 rural Veterans Affairs medical centers (VAMCs). Antibiotic days of therapy decreased significantly (P < .05) in the acute and long-term care units at both intervention sites, suggesting that tele-stewardship can effectively support antibiotic stewardship practices in rural VAMCs.
We used two sunflower genotypes displaying pericarp-imposed dormancy at high incubation temperatures (i.e. 30°C) to investigate the role of the pericarp as a limitation to oxygen availability to the embryo (hypoxia), and its impact on embryo abscisic acid (ABA) content and sensitivity to ABA. Results showed that both genotypes displayed very different oxygen threshold values for inhibition of embryo germination when incubation was performed at 30°C. Expression of dormancy in one genotype was therefore related to exacerbated embryo sensitivity to hypoxia, whereas in the other genotype, the pericarp appeared to act as a more severe restraint to oxygen entry. Increased sensitivity to hypoxia was, in part, related to increased sensitivity to ABA, but not to alterations in ABA metabolism. The activity of pericarp-microbial communities (bacteria and fungi) at high temperatures was also assessed as a potential determinant of hypoxia to the embryo. Oxygen consumption in pericarps incubated at 30°C was attenuated with antibiotics, which concomitantly promoted achene germination. In agreement with the observed more severe oxygen deprivation to the embryo exerted by the pericarp, the bacterial load in the pericarp was significantly higher in the commercial hybrid than in the inbred line; however, the application of antibiotics strongly reduced the bacterial colony counts for each genotype. Different bacterial and fungal communities, assessed through their profiles of carbon-source utilization, were determined between genotypes and after treatment with antibiotics. This work highlights the relationship between enhancement of sensitivity to hypoxia with incubation temperature and seed dormancy expression, and suggests that microbial activity might be part of the mechanism through which hypoxia is imposed.
To test the feasibility of using telehealth to support antimicrobial stewardship at Veterans Affairs medical centers (VAMCs) that have limited access to infectious disease-trained specialists.
A prospective quasi-experimental pilot study.
Two rural VAMCs with acute-care and long-term care units.
At each intervention site, medical providers, pharmacists, infection preventionists, staff nurses, and off-site infectious disease physicians formed a videoconference antimicrobial stewardship team (VAST) that met weekly to discuss cases and antimicrobial stewardship-related education.
Descriptive measures included fidelity of implementation, number of cases discussed, infectious syndromes, types of recommendations, and acceptance rate of recommendations made by the VAST. Qualitative results stemmed from semi-structured interviews with VAST participants at the intervention sites.
Each site adapted the VAST to suit their local needs. On average, sites A and B discussed 3.5 and 3.1 cases per session, respectively. At site A, 98 of 140 cases (70%) were from the acute-care units; at site B, 59 of 119 cases (50%) were from the acute-care units. The most common clinical syndrome discussed was pneumonia or respiratory syndrome (41% and 35% for sites A and B, respectively). Providers implemented most VAST recommendations, with an acceptance rate of 73% (186 of 256 recommendations) and 65% (99 of 153 recommendations) at sites A and B, respectively. Qualitative results based on 24 interviews revealed that participants valued the multidisciplinary aspects of the VAST sessions and felt that it improved their antimicrobial stewardship efforts and patient care.
This pilot study has successfully demonstrated the feasibility of using telehealth to support antimicrobial stewardship at rural VAMCs with limited access to local infectious disease expertise.
Functional circuits of the human brain emerge and change dramatically over the second half of gestation. It is possible that variation in neural functional system connectivity in utero predicts individual differences in infant behavioral development, but this possibility has yet to be examined. The current study examines the association between fetal sensorimotor brain system functional connectivity and infant postnatal motor ability. Resting-state functional connectivity data was obtained in 96 healthy human fetuses during the second and third trimesters of pregnancy. Infant motor ability was measured 7 months after birth using the Bayley Scales of Infant Development. Increased connectivity between the emerging motor network and regions of the prefrontal cortex, temporal lobes, posterior cingulate, and supplementary motor regions was observed in infants that showed more mature motor functions. In addition, females demonstrated stronger fetal-brain to infant-behavior associations. These observations extend prior longitudinal research back into prenatal brain development and raise exciting new ideas about the advent of risk and the ontogeny of early sex differences.
To examine the nutritional quality of menu items promoted in four (US) fast-food restaurant chains (McDonald’s, Burger King, Wendy’s, Taco Bell) in 2010 and 2013.
Menu items pictured on signs and menu boards were recorded at 400 fast-food restaurants across the USA. The Nutrient Profile Index (NPI) was used to calculate overall nutrition scores for items (higher scores indicate greater nutritional quality) and was dichotomized to denote healthier v. less healthy items. Changes over time in NPI scores and energy of promoted foods and beverages were analysed using linear regression.
Four hundred fast-food restaurants (McDonald’s, Burger King, Wendy’s, Taco Bell; 100 locations per chain).
NPI of fast-food items marketed at fast-food restaurants.
Promoted foods and beverages on general menu boards and signs remained below the ‘healthier’ cut-off at both time points. On general menu boards, pictured items became modestly healthier from 2010 to 2013, increasing (mean (se)) by 3·08 (0·16) NPI score points (P<0·001) and decreasing (mean (se)) by 130 (15) kJ (31·1 (3·65) kcal; P<0·001). This pattern was evident in all chains except Taco Bell, where pictured items increased in energy. Foods and beverages pictured on the kids’ section showed the greatest nutritional improvements. Although promoted foods on general menu boards and signs improved in nutritional quality, beverages remained the same or became worse.
Foods, and to a lesser extent, beverages, promoted on menu boards and signs in fast-food restaurants showed limited improvements in nutritional quality in 2013 v. 2010.
Treatment with proton-pump inhibitors (PPIs) might be associated with neuropsychological side effects. We examined the association between use of PPIs and depressive symptoms in an elderly population. Mood was assessed by the 30-item Geriatric Depression Scale (GDS) in all 344 inhabitants of Tuscania (Italy) aged 75 years and over, without exclusion criteria; depression was defined by a GDS score ≥11. Use of PPIs was associated with a higher GDS score in linear regression analysis (B = 2.43; 95% CI = 0.49–4.38; p = 0.014) after adjusting; also, use of PPIs was associated with increased adjusted probability of depression in logistic regression (OR = 2.38; 95% CI = 1.02–5.58; p = 0.045). Higher PPIs dosages were associated with increased probability of depression (p for trend = 0.014). This association was independent of the diagnosis of peptic disease, as well as the use of antidepressant medications. No association was found between use of H2-blockers or antacids and the GDS score. Calculation of the population attributable risk indicated that 14% of depression cases could be avoided by withdrawal of PPIs. Use of PPIs might represent a frequent cause of depression in older populations; thus, mood should be routinely assessed in elderly patients on PPIs.
A 2,4-D-resistant tall waterhemp population (FS) from Nebraska was evaluated for resistance to other TIR1 auxin receptor herbicides and to herbicides having alternative mechanisms of action using greenhouse bioassays and genetic markers. Atrazine, imazethapyr, lactofen, mesotrione, glufosinate, and glyphosate were applied in a single-dose bioassay, and tissue was collected from marked plants for genetic analysis. The FS population was not injured by atrazine or by imazethapyr. Approximately 50% of the plants survived lactofen and were actively growing 28 d after treatment. The population was susceptible to mesotrione, glufosinate, and glyphosate. Ametryn, chlorimuron-ethyl, 2,4-D, aminocyclopyraclor, aminopyralid, and picloram were applied in dose–response studies. The FS population was sensitive to ametryn, and the Ser-264-Gly substitution in the D1 protein was not detected, suggesting the lack of response to atrazine is not due to a target-site mutation. The FS population exhibited less than 50% injury to chlorimuron-ethyl at application rates 20 times the labeled use rate. The Ser-653-Asn acetolactate synthase (ALS) substitution, which confers resistance to imidazolinone herbicides, was present in the FS population. However, this does not explain the lack of response to the sulfonylurea herbicide, chlorimuron-ethyl. Sequencing of a portion of the PPX2L gene did not show the ΔG210 mutation that confers resistance to protoporphyrinogen oxidase–inhibiting herbicides, suggesting that other factors were responsible for waterhemp survival after lactofen application. The FS population was confirmed to be at least 30-fold resistant to 2,4-D relative to the susceptible populations. In addition, it was at least 3-fold less sensitive to aminopyralid and picloram, two other TIR1 auxin receptor herbicides, than the 2,4-D-susceptible populations were. These data indicated that the FS population contains both target and non–target site mechanisms conferring resistance to herbicides spanning at least three mechanisms of action: TIR1 auxin receptors, ALS inhibitors, and photosystem II inhibitors.
The importance of water and food security in the Middle East, the most water-short region in the world and one where food supplies are often impacted by drought, cannot be overstated. A significant proportion of the population of this region is both food insecure and water insecure— without access to enough safe and nutritious food nor an acceptable quantity and quality of water to lead healthy and active lives— and exposed to frequent droughts. Ensuring sustainable food and water security for the people of this region in the face of rising population and income, a changing climate, and growing demands for scarce water resources amid falling groundwater tables and increasing water pollution and salinization is one of the region's most urgent challenges, with significant political, environmental, social and economic implications. Indeed, prospects for peace and security in the Middle East depend to a very significant degree on water and food security.
This water and food challenge is exacerbated by and intertwined with the civil war in Syria and related conflicts and civil unrest in many other countries in the area. While not everyone agrees that water shortages and inadequate responses to a severe and long-lasting drought were among the root causes of the outbreak of the civil war in Syria, there is little doubt that the large numbers of refugees in neighboring countries have strained limited water supplies. The water and food security situations of the various countries of the region are further linked because so many countries depend on surface and underground water resources that cross international borders. Few countries in the region can fully control their water resources without engaging in cooperative approaches with other countries, which is fraught with difficulties in a region wracked by war and unrest. A major question in the region is therefore whether the quest for water and food security going forward will advance efforts toward cooperation and peace building or lead to further competition and conflict. While some observers have talked gloomily about the prospects for “water wars,” several scholars have argued persuasively that water is more often a mechanism for bringing people together to forge common solutions than a cause of war or violence.
For low-Reynolds-number shear flows of neutrally buoyant suspensions, the shear stress is often modelled using an effective viscosity that depends only on the solid fraction. As the Reynolds number (
) is increased and inertia becomes important, the effective viscosity also depends on the Reynolds number itself. The current experiments measure the torque for flows of neutrally buoyant particles in a coaxial-cylinder rheometer for solid fractions,
, from 10 % to 50 % and Reynolds numbers based on particle diameter from 2 to 1000. For experiments for Reynolds of
and solid fractions less than
, the effective viscosity increases with Reynolds number, in good agreement with recent numerical simulations found in the literature. At higher solid fractions over the same range of
, the results show a decrease in torque with shear rate. For Reynolds numbers greater than 100 and lower solids concentrations, the effective viscosity continues to increase with Reynolds number. However, based on comparisons with pure fluid measurements the increase in the measured effective viscosity results from the transition to turbulence. The particles augment the turbulence by increasing the magnitude of the measured torques and causing the flow to transition at lower Reynolds numbers. For the highest solid fractions, the measurements show a significant increase in the magnitude of the torques, but the effective viscosity is independent of Reynolds number.
In the frame of radiation driven wind theory (Castor et al.1975), we present self-consistent hydrodynamical solutions to the line-force parameters (k, α, δ) under LTE conditions. Hydrodynamic models are provided by HydWind (Curé 2004). We evaluate these results with those ones previously found in literature, focusing in different regions of the optical depth to be used to perform the calculations. The values for mass-loss rate and terminal velocity obtained from our calculations are also presented.
We also examine the line-force parameters for the case when large changes in ionization throughout the wind occurs (δ-slow solutions, Curé et al.2011).
We searched the first Gaia data release for Galactic central stars of planetary nebulae (CSPNe) for parallaxes in order to determine the distances of the hosting PNe. For the small sample of PNe for which a comparison is available, we show that distances derived from Gaia parallaxes agree, within the uncertainties, with the individual PN distances derived by other reliable methods. While Gaia parallaxes available for Galactic CSPNe are still few, and with high uncertainties, we studied the possibility of building a PN distance scale by using the Gaia distances as calibrators. We found that a scale built on the relation between the linear nebular radius and its surface brightness has promising future applications.
This paper starts with a brief historical review about the PNLF and its use as a distance indicator. Then the PNLF distances are compared with Surface Brightness Fluctuations (SBF) distances and Tip of the Red Giant Branch (TRGB) distances. A Monte Carlo method to generate simulated PNLFs is described, leading to the last subject: recent progress in reproducing the expected maximum final mass in old stellar populations, a stellar astrophysics enigma that has been challenging us for quite some time.
We review the state of our chemical evolution models for spiral and low mass galaxies. We analyze the consequences of using different stellar yields, infall rate laws and star formation prescriptions in the time/redshift evolution of the radial distributions of abundances, and other quantities as star formation rate or gas densities, in the Milky Way Galaxy; In particular we will study the evolution of the oxygen abundance radial gradient analyzing its relation with the ratio SFR/infall. We also compare the results with our old chemical evolution models, cosmological simulations and with the existing data, mainly with the planetary nebulae abundances.
We present studies using different observational techniques, along different frequencies, aiming to resolve and investigate jets, outflows, as well as compact and innermost regions of asymmetric planetary nebulae (PNe) and objects in transition to PN. All the information gathered allow us to explore the kinematics and other important properties of the structures that play a crucial role in the shaping of complex PNe morphologies, in particular, we explore the role of disks/tori as collimating engine of extreme axisymmetric PNe.
Magnetic fields are likely to be an efficient mechanism which can affect evolved intermediate mass stars (i.e. post-AGB stars and planetary nebulae) in different ways such as via the shaping of their envelope. However, observational probes for the presence of those fields are still scarce. I will present a summary of the works, including those from our group, on the detection and measurement of magnetic fields in various evolved objects.