Study of multi black hole and ring singularity apparent horizons

We study critical black hole separations for the formation of a common apparent horizon in systems of $N$ - black holes in a time symmetric configuration. We study in detail the aligned equal mass cases for $N=2,3,4,5$, and relate them to the unequal mass binary black hole case. We then study the apparent horizon of the time symmetric initial geometry of a ring singularity of different radii. The apparent horizon is used as indicative of the location of the event horizon in an effort to predict a critical ring radius that would generate an event horizon of toroidal topology. We found that a good estimate for this ring critical radius is $20/(3\pi) M$. We briefly discuss the connection of this two cases through a discrete black hole 'necklace' configuration.Comment: 31 pages, 21 figure

Explosive Radiation of Malpighiales Supports a Mid-Cretaceous Origin of Modern Tropical Rain Forests

Fossil data have been interpreted as indicating that Late Cretaceous tropical forests were open and dry adapted and that modern closed-canopy rain forest did not originate until after the Cretaceous-Tertiary (K/T) boundary. However, some mid-Cretaceous leaf floras have been interpreted as rain forest. Molecular divergence-time estimates within the clade Malpighiales, which constitute a large percentage of species in the shaded, shrub, and small tree layer in tropical rain forests worldwide, provide new tests of these hypotheses. We estimate that all 28 major lineages (i.e., traditionally recognized families) within this clade originated in tropical rain forest well before the Tertiary, mostly during the Albian and Cenomanian (112 - 94 Ma). Their rapid rise in the mid-Cretaceous may have resulted from the origin of adaptations to survive and reproduce under a closed forest canopy. This pattern may also be paralleled by other similarly diverse lineages and supports fossil indications that closed-canopy tropical rain forests existed well before the K/T boundary. This case illustrates that dated phylogenies can provide an important new source of evidence bearing on the timing of major environmental changes, which may be especially useful when fossil evidence is limited or controversial.Organismic and Evolutionary Biolog

Magnetism and superconductivity driven by identical 4ff states in a heavy-fermion metal

The apparently inimical relationship between magnetism and superconductivity has come under increasing scrutiny in a wide range of material classes, where the free energy landscape conspires to bring them in close proximity to each other. This is particularly the case when these phases microscopically interpenetrate, though the manner in which this can be accomplished remains to be fully comprehended. Here, we present combined measurements of elastic neutron scattering, magnetotransport, and heat capacity on a prototypical heavy fermion system, in which antiferromagnetism and superconductivity are observed. Monitoring the response of these states to the presence of the other, as well as to external thermal and magnetic perturbations, points to the possibility that they emerge from different parts of the Fermi surface. This enables a single 4$f$ state to be both localized and itinerant, thus accounting for the coexistence of magnetism and superconductivity.Comment: 4 pages, 4 figure

Improving Mechanical Properties and Reaction to Fire of EVA/LLDPE Blends for Cable Applications with Melamine Triazine and Bentonite Clay

The high flame-retardant loading required for ethylene-vinyl acetate copolymer blends with polyethylene (EVA-PE) employed for insulation and sheathing of electric cables represents a significant limitation in processability and final mechanical properties. In this work, melamine triazine (TRZ) and modified bentonite clay have been investigated in combination with aluminum trihydroxide (ATH) for the production of EVA-PE composites with excellent fire safety and improved mechanical properties. Optimized formulations with only 120 parts per hundred resin (phr) of ATH can achieve self-extinguishing behavior according to the UL94 classification (V0 rating), as well as reduced combustion kinetics and smoke production. Mechanical property evaluation shows reduced stiffness and improved elongation at break with respect to commonly employed EVA-PE/ATH composites. The reduction in filler content also provides improved processability and cost reductions. The results presented here allow for a viable and halogen-free strategy for the preparation of high performing EVA-PE composites

Clinical factors associated with high glycemic variability defined by coefficient of variation in patients with type 2 diabetes

Antecedentes: La Variabilidad Glucémica Alta (VHG) ha convertirse en un predictor más fuerte de hipoglucemia. Sin embargo, aún se desconocen los factores clínicos asociados con el VHG. Objetivo:Determinar las variables clínicas que se asociaron con un coeficiente de variación (CV) superior al 36% evaluado mediante monitorización continua de glucosa (MCG) en un grupo de pacientes con diabetes mellitus. Métodos: Se evaluó una cohorte de pacientes con diabetes tipo 2 (T2D). Se evaluaron variables demográficas, HbA1c, tasa de filtración glomerular (TFG) y régimen de tratamiento. Se realizó un análisis bivariado, para evaluar la asociación entre la variable resultado (CV > 36%) y cada una de las variables independientes. Se construyó un modelo multivariado para evaluar las asociaciones después de controlar las variables de confusión. Resultados:Se analizaron los datos de MCG de 274 pacientes. CV> 36% estuvo presente en 56 pacientes (20,4%). En el análisis bivariado se incluyeron variables demográficas y clínicas, como tiempo desde el diagnóstico, antecedente de hipoglucemia, A1c, FG y tratamiento instaurado. En el análisis multivariante, FG 9% (OR 2,81; IC 1,05,7,51; p:0,04) y antecedentes de hipoglucemia (OR 2,09; IC 1,02, 4,32; p: 0,04) se asociaron con VHG. El tratamiento con iDPP4 (OR 0,39; IC 0,19, 0,82; p: 0,01) y AGLP1 (OR 0,08; IC 0,01, 0,68; p: 0,02) se asoció inversamente con la VG. Conclusión:Variables clínicas como FG 9% y antecedentes de hipoglucemia se asocian a un VG alto. Nuestros datos sugieren que el uso de tecnología y tratamientos capaces de reducir la variabilidad glucémica podría ser útil en esta población para reducir el riesgo de hipoglucemia y mejorar el control glucémico.Q3Background: High glycemic Variability (HGV) has become a stronger predictor of hypoglycemia. However, clinical factors associate with HGV still are unknown. Objective: To determine clinical variables that were associated with a coefficient of variation (CV) above 36% evaluated by continuous glucose monitoring (CGM) in a group of patients with diabetes mellitus. Methods: A cohort of patients with type 2 diabetes (T2D) was evaluated. Demographic variables, HbA1c, glomerular filtration rate (GFR) and treatment regimen were assessed. A bivariate analysis was performed, to evaluate the association between the outcome variable (CV> 36%) and each of the independent variables. A multivariate model was constructed to evaluate associations after controlling for confounding variables. Results: CGM data from 274 patients were analyzed. CV> 36% was present in 56 patients (20.4%). In the bivariate analysis, demographic and clinical variables were included, such as time since diagnosis, hypoglycemia history, A1c, GFR and treatment established. In the multivariate analysis, GFR 9% (OR 2.81; CI 1.05,7.51; p:0.04) and hypoglycemia history (OR 2.09; CI 1.02,4.32; p:0.04) were associated with HGV. Treatment with iDPP4 (OR 0.39; CI 0.19,0.82; p:0.01) and AGLP1 (OR 0.08; CI 0.01,0.68; p:0.02) was inversely associated with GV. Conclusion: Clinical variables such as GFR 9% and a history of hypoglycemia are associated with a high GV. Our data suggest that the use of technology and treatments able to reduce glycemic variability could be useful in this population to reduce the risk of hypoglycemia and to improve glycemic control.Revista Internacional - Indexad

Essential nonlinearities in hearing

Our hearing organ, the cochlea, evidently poises itself at a Hopf bifurcation to maximize tuning and amplification. We show that in this condition several effects are expected to be generic: compression of the dynamic range, infinitely shrap tuning at zero input, and generation of combination tones. These effects are "essentially" nonlinear in that they become more marked the smaller the forcing: there is no audible sound soft enough not to evoke them. All the well-documented nonlinear aspects of hearing therefore appear to be consequences of the same underlying mechanism.Comment: 4 pages, 3 figure

Community-Based Climate Change Adaptation Action Plans to Support Climate-Resilient Development in the Eastern African Highlands

Smallholder farmers in the Eastern African Highlands depend on rain-fed agriculture for their livelihoods. Climate adaptation and sustainable development goals must be targeted in an integrated way to better match farmers’ realities and address local priorities and vulnerabilities in these areas. To support climate-resilient development in the Eastern African Highlands, 224 local stakeholders were engaged in the development of community-based climate change adaptation action plans for the Jimma Highlands in Ethiopia, Taita Hills in Kenya and Mount Kilimanjaro in Tanzania. Participatory methods, high-resolution climate projections and the United Nations Development Programme’s (UNDP’s) guidelines were used in the design of these climate action plans with specific objectives to: 1) engage stakeholders to increase understanding of climate change impacts, adaptation options and their potential trade-offs, 2) build their capacities to design climate change adaptation projects, 3) empower stakeholders to identify existing vulnerabilities and enhance climate resilience and 4) strengthen networks to facilitate information access and sharing. Increased risk of water stress and reduction of agricultural productivity were the most frequently identified climate-change-induced problems in the three areas. The developed action plans target the underlying causes of these problems and describe sector-specific responses, activities, critical barriers and opportunities and support the National Adaptation Programmes of Action.Peer reviewe

Comparison of health behaviours between cancer survivors and the general population:a cross-sectional analysis of the Lifelines cohort

Purpose: To compare the differences in lifestyle behaviours between cancer survivors (CSs) and cancer-free participants in a large and representative population-based cohort. Methods: We included 115,257 adults from the Lifelines cohort. Cancer status was self-reported, and health behaviours were measured (e.g. body mass index [BMI]) or assessed by questionnaire (e.g. physical activity, smoking, alcohol consumption, sedentary behaviour and diet). The data were then categorised for logistic regression analysis, stratified and adjusted by sex and age (< 55 vs ≥ 55 years). Results: CSs (5473; 4.7%) were diagnosed 9 ± 8.5 years before data collection, were older (mean age 55.4 vs 44.4 years) and more often female (66.6% vs 33.4%) than the cancer-free participants. They were also more likely to be physically active and to have a better diet, and also less likely to be alcohol drinkers; but, were more likely to have a higher BMI, be former smokers and to be sedentary. After adjustment for sex and age, however, BMI was more likely to be normal, physical activity was more likely to be higher and smoking to be prevalent in CSs. Current smoking was also significantly higher among females and those aged < 55 years who were CSs than for those with no history of cancer. Conclusions: In this population-based cohort, CSs have health behaviour comparable to those without a cancer diagnosis. Implications for cancer survivors: Smoking cessation strategies should target all CSs, but efforts could yield greatest benefit if they target females and those younger than 55 years