•A well planned polyelectrolyte dosing strategy plays a crucial role in successful coagulation–flocculation process.•pZ–pH plots are a powerful tool to plan polyelectrolytes dosage and to discover ...coagulation–flocculation mechanisms.•Previously prepared polyelectrolytes dispersions improved resulting water quality after a coagulation–flocculation process.
Based on the polyelectrolyte-contaminant physical and chemical interactions at the molecular level, this article analyzed and discussed the coagulation–flocculation and chemical precipitation processes in order to improve their efficiency. Bench experiments indicate that water pH, polyelectrolyte (PE) dosing strategy and cationic polyelectrolyte addition are key parameters for the stability of metal–PE complexes. The coagulation–flocculation mechanism is proposed based on zeta potential (ζ) measurement as the criteria to define the electrostatic interaction between pollutants and coagulant–flocculant agents. Polyelectrolyte and wastewater dispersions are exposed to an electrophoretic effect to determine ζ. Finally, zeta potential values are compared at pH 9, suggesting the optimum coagulant dose at 162mg/L polydadmac and 67mg/L of flocculant, since a complete removal of TSS and turbidity is achieved. Based on the concentration of heavy metals (0.931mg/L Sn, 0.7mg/L Fe and 0.63mg/L Pb), treated water met the Mexican maximum permissible limits. In addition, the treated water has 45mg O2/L chemical oxygen demand (COD) and 45mg C/L total organic carbon (TOC). The coagulation–flocculation mechanism is proposed taking into account both: zeta potential (ζ)–pH measurement and chemical affinity, as the criteria to define the electrostatic and chemical interaction between pollutants and polyelectrolytes.
Objetivo Estimar y analizar para el período 1990 al 2010 los patrones regionales de la esperanza de vida al nacer en México por medio del método de regresión lineal.Materiales y Métodos Se utiliza la ...regresión lineal para obtener la esperanza de vida a nivel estatal y éste considera variables como la tasa bruta o cruda de mortalidad y la población mayor a 65 años. Esto permite conocer el nivel de convergencia entre los estados.Resultados Existe un patrón de convergencia que sugiere que las diferencias de los niveles de esperanza de vida se han reducido entre los estados durante el período de estudio, esta tendencia se presenta también a nivel regional.Discusión Se puede mencionar que este análisis puede ser útil en la evaluación de las políticas de salud pública de México que se han centrado en la disminución de las desigualdades en salud entre las poblaciones más pobres y vulnerables. Asimismo, este tipo de método permite tener un método alternativo para conocer las condiciones de acceso a los servicios de salud y conocer las expectativas de vida de la población.
As fraturas do complexo zigomático-orbitário são bastante frequentes devido a sua localização e projeção na face, podendo gerar grandes transtornos funcionais e estéticos ao paciente. O osso ...zigomático é essencial na configuração da face, sendo a principal estrutura formadora do terço médio dela. Os traumas que mais frequentemente provocam fraturas do complexo zigomático-orbitário são agressões físicas, acidentes de trânsito e esportivos. O tipo de fratura, tempo decorrido, a severidade e o envolvimento de outras estruturas faciais influenciam a modalidade de tratamento a ser empregado. O presente trabalho apresenta um caso clínico de fratura do complexo zigomático-orbitário esquerdo, diagnosticada tardiamente, e tratada por meio de osteotomia, redução e fixação em três pontos com placas e parafusos do sistema 1.5, e reconstrução do assoalho orbitário com tela de titânio.
Sloth bears (Melursus ursinus) are endemic to the Indian subcontinent. As a result of continued habitat loss and degradation over the past century, sloth bear populations have been in steady decline ...and now exist only in isolated or fragmented habitat across the entire range. We investigated the genetic connectivity of the sloth bear meta-population in five tiger reserves in the Satpura-Maikal landscape of central India. We used noninvasively collected fecal and hair samples to obtain genotypic information using a panel of seven polymorphic loci. Out of 194 field collected samples, we identified 55 individuals in this meta-population. We found that this meta-population has moderate genetic variation, and is subdivided into two genetic clusters. Further, we identified five first-generation migrants and signatures of contemporary gene flow. We found evidence of sloth bears in the corridor between the Kanha and Pench Tiger Reserves, and our results suggest that habitat connectivity and corridors play an important role in maintaining gene flow in this meta-population. These corridors face several anthropogenic and infrastructure development threats that have the potential to sever ongoing gene flow, if policies to protect them are not put into action immediately.
Age‐associated DNA‐methylation profiles have been used successfully to develop highly accurate biomarkers of age ("epigenetic clocks") in humans, mice, dogs, and other species. Here we present ...epigenetic clocks for African and Asian elephants. These clocks were developed using novel DNA methylation profiles of 140 elephant blood samples of known age, at loci that are highly conserved between mammalian species, using a custom Infinium array (HorvathMammalMethylChip40). We present epigenetic clocks for Asian elephants (Elephas maximus), African elephants (Loxodonta africana), and both elephant species combined. Two additional human‐elephant clocks were constructed by combining human and elephant samples. Epigenome‐wide association studies identified elephant age‐related CpGs and their proximal genes. The products of these genes play important roles in cellular differentiation, organismal development, metabolism, and circadian rhythms. Intracellular events observed to change with age included the methylation of bivalent chromatin domains, and targets of polycomb repressive complexes. These readily available epigenetic clocks can be used for elephant conservation efforts where accurate estimates of age are needed to predict demographic trends.
DNA methylation aging clocks for African and Asian elephants. Some of these clocks apply to humans as well. Parts of the graphic were created by Hollis Burbank‐Hammerlund, Sandra Oviedo, and BioRender.com.
Background
Coronavirus disease 2019 (COVID‐19) interferes with the vascular endothelium. It is not known whether COVID‐19 additionally affects arterial stiffness.
Methods
This case–control study ...compared brachial‐ankle pulse wave (baPWV) and carotid‐femoral pulse wave velocities (cfPWV) of acutely ill patients with and without COVID‐19.
Results
Twenty‐two COVID‐19 patients (50% females, 77 67–84 years) were compared with 22 age‐ and sex‐matched controls. In COVID‐19 patients, baPWV (19.9 18.4–21.0 vs. 16.0 14.2–20.4, P = 0.02) and cfPWV (14.3 13.4–16.0 vs. 11.0 9.5–14.6, P = 0.01) were higher than in the controls. In multiple regression analysis, COVID‐19 was independently associated with higher cfPWV (β = 3.164, P = 0.004) and baPWV (β = 3.532, P = 0.003). PWV values were higher in nonsurvivors. In survivors, PWV correlated with length of hospital stay.
Conclusion
COVID‐19 appears to be related to an enhanced PWV reflecting an increase in arterial stiffness. Higher PWV might be related to an increased length of hospital stay and mortality.
Asiatic black bears (Ursus thibetanus) have a widespread distribution in mountain landscapes, and are considered vulnerable globally, but are low-priority species for conservation in Nepal. Habitat ...fragmentation, illegal hunting, and human-bear conflict are the major threats to Asiatic black bears across their global range. Having an adequate level of genetic variation in a population helps with adapting to rapidly changing environments, and thus is important for the long-term health of bear populations. Accordingly, we conducted non-invasive surveys of bear populations in the Annapurna Conservation Area (ACA) to elucidate genetic diversity, genetic structure, and the phylogenetic relationship of Asiatic black bears from this region of Nepal to other subspecies. To assess levels of genetic diversity and population genetic structure, we genotyped eight microsatellite loci using 147 samples, identifying 60 individuals in an area of approximately 525 km2. We found that the Asiatic black bear population in the ACA has maintained high levels of genetic diversity (HE = 0.76) as compared to other bear populations from range countries. We did not detect a signature of population substructure among sampling localities and this suggests that animals are moving freely across the landscape within the ACA. We also detected a moderate population size that may increase with the availability of suitable habitat in the ACA, so bear-related conflict should be addressed to ensure the long-term viability of this expanding bear populations. Primers specific to bears were designed to amplify a 675 bp fragment of the mitochondrial control region from the collected samples. Three haplotypes were observed from the entire conservation area. The complete mitochondrial genome (16,771 bp), the first obtained from wild populations of the Himalayan black bear (U. t. laniger), was also sequenced to resolve the phylogenetic relationships of closely related subspecies of Asiatic black bears. The resulting phylogeny indicated that Himalayan black bear populations in Nepal are evolutionary distinct from other known subspecies of Asiatic black bears.
El presente ensayo analiza el ergastolo o cadena perpetua dentro de la legislación italiana, señalando sus diversas contradicciones con principios constitucionales, en especial: la función ...reeducativa de la pena, la proporcionalidad y la prohibición de tratos crueles e inhumanos. A la par, se realiza un esbozo de la jurisprudencia constitucional italiana y europea que, sobre el tema se ha pronunciado. En conclusión, se afirma que la cadena perpetua es una sanción ilegítima en cualquier forma. A lo largo del ensayo, también se realizan comentarios y comparaciones con la legislación y jurisprudencia de Argentina, Brasil y México a fin de analizar semejanzas y diferencias.
Understanding the patterns of gene flow of an endangered species metapopulation occupying a fragmented habitat is crucial for landscape-level conservation planning and devising effective conservation ...strategies. Tigers (Panthera tigris) are globally endangered and their populations are highly fragmented and exist in a few isolated metapopulations across their range. We used multi-locus genotypic data from 273 individual tigers (Panthera tigris tigris) from four tiger populations of the Satpura–Maikal landscape of central India to determine whether the corridors in this landscape are functional. This 45 000 km2 landscape contains 17% of India's tiger population and 12% of its tiger habitat. We applied Bayesian and coalescent-based analyses to estimate contemporary and historical gene flow among these populations and to infer their evolutionary history. We found that the tiger metapopulation in central India has high rates of historical and contemporary gene flow. The tests for population history reveal that tigers populated central India about 10 000 years ago. Their population subdivision began about 1000 years ago and accelerated about 200 years ago owing to habitat fragmentation, leading to four spatially separated populations. These four populations have been in migration–drift equilibrium maintained by high gene flow. We found the highest rates of contemporary gene flow in populations that are connected by forest corridors. This information is highly relevant to conservation practitioners and policy makers, because deforestation, road widening and mining are imminent threats to these corridors.
Clinical and experimental observations indicate a role for VEGF secreted by the retinal pigment epithelium (RPE) in the maintenance of the choriocapillaris (CC). VEGF in mice is produced as three ...isoforms, VEGF120, VEGF164, and VEGF188, that differ in their ability to bind heparan sulfate proteoglycan. RPE normally produces the more soluble isoforms, VEGF120 and VEGF164, but virtually no VEGF188, reflecting the fact that molecules secreted by the RPE must diffuse across Bruch's membrane (BrM) to reach the choriocapillaris. To determine the role of RPE-derived soluble VEGF on the choriocapillaris survival, we used mice that produce only VEGF188. VEGF188/188 mice exhibited normal choriocapillaris development. However, beginning at 7 months of age, we observed a progressive degeneration characterized by choriocapillaris atrophy, RPE and BrM abnormalities, culminating in areas of RPE loss and dramatic choroidal remodeling. Increased photoreceptor apoptosis in aged VEGF188/188 mice led to a decline in visual acuity as detected by electroretinogram (ERG). These changes are reminiscent of geographic atrophy (GA) and point to a role for RPE-derived VEGF in the maintenance of the choriocapillaris.
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