Roughly one-third of the rural population in developing countries lives in arid and semiarid regions, facing recurrent water scarcity. This is likely to become an even more common situation with ...climate change. This paper analyzes the impact of rainfall fluctuations during the gestational period on health at birth in the Brazilian semiarid, highlighting the role of water scarcity as a determinant of early life health. We find that negative rainfall shocks are robustly correlated with higher infant mortality, lower birth weight, and shorter gestation periods. Mortality effects are concentrated on intestinal infections and malnutrition, and are greatly minimized when the local public health infrastructure is sufficiently developed (municipality coverage of piped water and sanitation). We also find that effects are stronger during the fetal period (2nd trimester of gestation), for children born during the dry season, and for mortality immediately after birth. Our estimates suggest that expansions in public health infrastructure would be a cost-effective way of reducing the response of infant mortality to rainfall scarcity.
•We analyze the impact of rainfall during gestation on health at birth.•We look at the Brazilian semiarid, where water scarcity is a major problem.•Negative rainfall shocks lead to higher infant mortality and worse health at birth.•Effects are minimized when water and sanitation coverages are sufficiently high.•Expansions in public health infrastructure would be a cost-effective solution.
Summary
Changes in resources (e.g. nitrogen) and enemies (e.g. foliar pathogens) are key drivers of plant diversity and composition. However, their effects have not been connected to the niche and ...fitness differences that determine multispecies coexistence.
Here, we combined a structuralist theoretical approach with a detailed grassland experiment factorially applying nitrogen addition and foliar fungal pathogen suppression to evaluate the joint effect of nitrogen and pathogens on niche and fitness differences, across a gradient from two to six interacting species.
Nitrogen addition and pathogen suppression modified species interaction strengths and intrinsic growth rates, leading to reduced multispecies fitness differences. However, contrary to expected, we also observed that they promote stabilising niche differences. Although these modifications did not substantially alter species richness, they predicted major changes in community composition. Indirect interactions between species explained these community changes in smaller assemblages (three and four species) but lost importance in favour of direct pairwise interactions when more species were involved (five and six).
Altogether, our work shows that explicitly considering the number of interacting species is critical for better understanding the direct and indirect processes by which nitrogen enrichment and pathogen communities shape coexistence in grasslands.
A novel graphene antenna composed of a graphene dipole and four auxiliary graphene sheets oriented at 90∘ to each other is proposed and analyzed. The sheets play the role of reflectors. A detailed ...group-theoretical analysis of symmetry properties of the discussed antennas has been completed. Through electric field control of the chemical potentials of the graphene elements, the antenna can provide a quasi-omnidirectional diagram, a one- or two-directional beam regime, dynamic control of the beam width and, due to the vertical orientation of the dipole with respect to the base substrate, a 360∘ beam steering in the azimuth plane. An additional graphene layer on the base permits control of the radiation pattern in the θ-direction. Radiation patterns in different working states of the antenna are considered using symmetry arguments. We discuss the antenna parameters such as input reflection coefficient, total efficiency, front-to-back ratio, and gain. An equivalent circuit of the antenna is suggested. The proposed antenna operates at frequencies between 1.75 THz and 2.03 THz. Depending on the active regime defined by the chemical potentials set on the antenna graphene elements, the maximum gain varies from 0.86 to 1.63.
Thyroid hormone signaling is customized in a time and cell-specific manner by the deiodinases, homodimeric thioredoxin fold containing selenoproteins. This ensures adequate T3 action in developing ...tissues, healthy adults and many disease states. D2 activates thyroid hormone by converting the pro-hormone T4 to T3, the biologically active thyroid hormone. D2 expression is tightly regulated by transcriptional mechanisms triggered by endogenous as well as environmental cues. There is also an on/off switch mechanism that controls D2 activity that is triggered by catalysis and functions via D2 ubiquitination/deubiquitination. D3 terminates thyroid hormone action by inactivation of both T4 and T3 molecules. Deiodinases play a role in thyroid hormone homeostasis, development, growth and metabolic control by affecting the intracellular levels of T3 and thus gene expression on a cell-specific basis. In many cases, tight control of these pathways by T3 is achieved with coordinated reciprocal changes in D2-mediated thyroid hormone activation D3-mediated thyroid hormone inactivation.
Levothyroxine (LT4) is a form of thyroid hormone used to treat hypothyroidism. In the brain, T4 is converted to the active form T3 by type 2 deiodinase (D2). Thus, it is intriguing that carriers of ...the Thr92Ala polymorphism in the D2 gene (DIO2) exhibit clinical improvement when liothyronine (LT3) is added to LT4 therapy. Here, we report that D2 is a cargo protein in ER Golgi intermediary compartment (ERGIC) vesicles, recycling between ER and Golgi. The Thr92-to-Ala substitution (Ala92-D2) caused ER stress and activated the unfolded protein response (UPR). Ala92-D2 accumulated in the trans-Golgi and generated less T3, which was restored by eliminating ER stress with the chemical chaperone 4-phenyl butyric acid (4-PBA). An Ala92-Dio2 polymorphism-carrying mouse exhibited UPR and hypothyroidism in distinct brain areas. The mouse refrained from physical activity, slept more, and required additional time to memorize objects. Enhancing T3 signaling in the brain with LT3 improved cognition, whereas restoring proteostasis with 4-PBA eliminated the Ala92-Dio2 phenotype. In contrast, primary hypothyroidism intensified the Ala92-Dio2 phenotype, with only partial response to LT4 therapy. Disruption of cellular proteostasis and reduced Ala92-D2 activity may explain the failure of LT4 therapy in carriers of Thr92Ala-DIO2.
Economic Shocks and Crime Dix-Carneiro, Rafael; Soares, Rodrigo R.; Ulyssea, Gabriel
American economic journal. Applied economics,
10/2018, Volume:
10, Issue:
4
Journal Article
Peer reviewed
Open access
This paper studies the effect of changes in economic conditions on crime. We exploit the 1990s trade liberalization in Brazil as a natural experiment generating exogenous shocks to local economies. ...We document that regions exposed to larger tariff reductions experienced a temporary increase in crime following liberalization. Next, we investigate through what channels the trade-induced economic shocks may have affected crime. We show that the shocks had significant effects on potential determinants of crime, such as labor market conditions, public goods provision, and income inequality. We propose a novel framework exploiting the distinct dynamic responses of these variables to obtain bounds on the effect of labor market conditions on crime. Our results indicate that this channel accounts for 75 to 93 percent of the effect of the trade-induced shocks on crime.
A wider application of living donor liver transplantation is limited by donor morbidity concerns. An observational cohort of 760 living donors accepted for surgery and enrolled in the Adult‐to‐Adult ...Living Donor Liver Transplantation cohort study provides a comprehensive assessment of incidence, severity and natural history of living liver donation (LLD) complications. Donor morbidity (assessed by 29 specific complications), predictors, time from donation to complications and time from complication onset to resolution were measured outcomes over a 12‐year period. Out of the 760 donor procedures, 20 were aborted and 740 were completed. Forty percent of donors had complications (557 complications among 296 donors), mostly Clavien grades 1 and 2. Most severe counted by complication category; grade 1 (minor, n = 232); grade 2 (possibly life‐threatening, n = 269); grade 3 (residual disability, n = 5) and grade 4 (leading to death, n = 3). Hernias (7%) and psychological complications (3%) occurred >1 year postdonation. Complications risk increased with transfusion requirement, intraoperative hypotension and predonation serum bilirubin, but did not decline with the increased center experience with LLD. The probability of complication resolution within 1 year was overall 95%, but only 75% for hernias and 42% for psychological complications. This report comprehensively quantifies LLD complication risk and should inform decision making by potential donors and their caregivers.
This large multicenter series from the A2ALL consortium provides a definitive report of the incidence and severity of live liver donor complications, and includes long‐term follow‐up allowing for a definition of the natural history of complications.
Abstract
We develop a search model of informal labour markets with realistic labour regulations, including minimum wage, and heterogeneous workers and firms. Smaller firms and lower wages in the ...informal sector emerge endogenously as firms and workers decide whether to comply with regulations. Because skilled and unskilled workers are imperfect substitutes in production, the model uniquely captures the informality consequences of shocks that affect returns to skill, such as rising educational levels. The model also reproduces empirical patterns incompatible with other frameworks: the presence of skilled and unskilled workers in the formal and informal sectors, the rising share of skilled workers by firm size, and formal and firm-size wage premiums that vary by skill level. We estimate the model using 2003 data from Brazil and show that it successfully predicts labour market changes observed between 2003 and 2012. Under a range of different assumptions, changes in workforce composition appear as the main drivers of the reduction in informality over this period. Policy simulations using the estimated model suggest that progressive payroll taxes are a cost-effective way to reduce informality.
Abstract
This paper documents an externality from the agricultural use of the most widely applied herbicide in the world—glyphosate—on birth outcomes of surrounding populations. We focus on the ...subclinical effects of water contamination in areas distant from the original locations of application. Our identification relies on: (i) the regulation allowing the introduction of genetically modified seeds in Brazil; (ii) the potential gain in municipality-level productivity from adoption of genetically modified soybean seeds and the strong complementary between these seeds and glyphosate; and (iii) the direction of water flow within water basins. We document a significant deterioration in birth outcomes for populations downstream from locations that are likely to have increased relatively more the use of glyphosate. According to our preferred specification, the average increase in glyphosate use in the sample during 2000–10 period led to an increase of 5% of the average in infant mortality rate.
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