Thermocatalytic membrane distillation for clean water production

Abstract Natural water bodies and treated wastewaters contain an increasing variety of organic micropollutants with a negative impact on ecosystems and human health. Herein, we propose an integrated process based on membrane distillation and advanced oxidation, in which thermal energy is simultaneously used to drive the permeation of pure water through a hydrophobic membrane and to activate the generation of reactive oxygen species by a thermocatalytic perovskite, namely Ce-doped strontium ferrate. At a feed temperature of 65 °C, our thermocatalytic distillation apparatus can effectively retain and degrade bisphenol A, as model pollutant, while producing distilled water at the constant rate of 1.60 ± 0.03 L h−1 m−2, over four continuous runs. Moreover, the membrane makes degradation faster by concentrating the pollutant during filtration. Our technology is effective in the production of pure water without creating a toxic concentrate, it relies on simple process design, and it does not require high pressure or additional chemicals. In addition, it can potentially work continuously driven by renewable thermal energies or waste heat

Multi-year patterns in testosterone, cortisol and corticosterone in baleen from adult males of three whale species

© The Author(s), 2018. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Conservation Physiology 6 (2018): coy049, doi:10.1093/conphys/coy049.Male baleen whales have long been suspected to have annual cycles in testosterone, but due to difficulty in collecting endocrine samples, little direct evidence exists to confirm this hypothesis. Potential influences of stress or adrenal stress hormones (cortisol, corticosterone) on male reproduction have also been difficult to study. Baleen has recently been shown to accumulate steroid hormones during growth, such that a single baleen plate contains a continuous, multi-year retrospective record of the whale’s endocrine history. As a preliminary investigation into potential testosterone cyclicity in male whales and influences of stress, we determined patterns in immunoreactive testosterone, two glucocorticoids (cortisol and corticosterone), and stable-isotope (SI) ratios, across the full length of baleen plates from a bowhead whale (Balaena mysticetus), a North Atlantic right whale (Eubalaena glacialis) and a blue whale (Balaenoptera musculus), all adult males. Baleen was subsampled at 2 cm (bowhead, right) or 1 cm (blue) intervals and hormones were extracted from baleen powder with methanol, followed by quantification of all three hormones using enzyme immunoassays validated for baleen extract of these species. Baleen of all three males contained regularly spaced peaks in testosterone content, with number and spacing of testosterone peaks corresponding well to SI data and to species-specific estimates of annual baleen growth rate. Cortisol and corticosterone exhibited some peaks that co-occurred with testosterone peaks, while other glucocorticoid peaks occurred independent of testosterone peaks. The right whale had unusually high glucocorticoids during a period with a known entanglement in fishing gear and a possible disease episode; in the subsequent year, testosterone was unusually low. Further study of baleen testosterone patterns in male whales could help clarify conservation- and management-related questions such as age of sexual maturity, location and season of breeding, and the potential effect of anthropogenic and natural stressors on male testosterone cycles.This work was supported by (1) the Arizona Board of Regents Technology Research Initiative Fund; (2) the Center for Bioengineering Innovation at Northern Arizona University; (3) the Greenland Institute of Natural Resources; (4) the Woods Hole Oceanographic Institution Ocean Life Institute and (5) Fisheries and Ocean Canada’s (DFO) Priorities and Partnership Strategic Initiatives Fund and Oceans Protection Plan

Direct estimation of genome mutation rates from pedigrees in free-ranging baleen whales

Current low germline mutation rate (𝜇) estimates in baleen whales have greatly influenced research ranging from assessments of whaling impacts to evolutionary cancer biology. However, the reported rates were subject to methodological errors and uncertainty. We estimated 𝜇 directly from pedigrees in natural populations of four baleen whale species and the results were similar to primates. The implications of revised 𝜇 values include pre-exploitation population sizes at 14% of previous genetic diversity-based estimates and the conclusion that 𝜇 in itself is insufficient to explain low cancer rates in gigantic mammals (i.e., Peto’s Paradox). We demonstrate the feasibility of estimating 𝜇 from whole genome pedigree data in natural populations, which has wide-ranging implications for the many ecological and evolutionary inferences that rely on 𝜇

Circulating Glucagon 1-61 Regulates Blood Glucose by Increasing Insulin Secretion and Hepatic Glucose Production

Glucagon is secreted from pancreatic a cells, and hypersecretion (hyperglucagonemia) contributes to diabetic hyperglycemia. Molecular heterogeneity in hyperglucagonemia is poorly investigated. By screening human plasma using high-resolution-proteomics, we identified several glucagon variants, among which proglucagon 1-61 (PG 1-61) appears to be the most abundant form. PG 1-61 is secreted in subjects with obesity, both before and after gastric bypass surgery, with protein and fat as the main drivers for secretion before surgery, but glucose after. Studies in hepatocytes and in b cells demonstrated that PG 1-61 dose-dependently increases levels of cAMP, through the glucagon receptor, and increases insulin secretion and protein levels of enzymes regulating glycogenolysis and gluconeogenesis. In rats, PG 1-61 increases blood glucose and plasma insulin and decreases plasma levels of amino acids in vivo. We conclude that glucagon variants, such as PG 1-61, may contribute to glucose regulation by stimulating hepatic glucose production and insulin secretion

Migrant tuberculosis: the extent of transmission in a low burden country

<p>Abstract</p> <p>Background</p> <p>Human migration caused by political unrest, wars and poverty is a major topic in international health. Infectious diseases like tuberculosis follow their host, with potential impact on both the migrants and the population in the recipient countries. In this study, we evaluate <it>Mycobacterium tuberculosis </it>transmission between the national population and migrants in Denmark.</p> <p>Methods</p> <p>Register study based on IS<it>6110</it>-RFLP results from nationwide genotyping of tuberculosis cases during 1992 through 2004. Cases with 100% identical genotypes were defined as clustered and part of a transmission chain. Origin of clusters involving both Danes and migrants was defined as Danish/migrant/uncertain. Subsequently, the proportion of cases likely infected by the "opposite" ethnic group was estimated.</p> <p>Results</p> <p>4,631 cases were included, representing 99% of culture confirmed cases during 1992 through 2004. Migrants contributed 61.6% of cases. Up to 7.9% (95% CI 7.0-8.9) of migrants were infected by Danes. The corresponding figure was 5.8% (95% CI 4.8-7.0) for Danes. Thus, transmission from Danes to migrants occurred up to 2.5 (95% CI 1.8-3.5) times more frequent than vice versa (OR = 1). A dominant strain, Cluster-2, was almost exclusively found in Danes, particular younger-middle-aged males.</p> <p>Conclusions</p> <p>Transmission between Danes and migrants is limited, and risk of being infected by the "opposite" ethnic group is highest for migrants. TB-control efforts should focus on continues micro-epidemics, e.g. with Cluster-2 in Danes, prevention of reactivation TB in high-risk migrants, and outbreaks in socially marginalized migrants, such as Somalis and Greenlanders. Fears that TB in migrants poses a threat for resident Danes seem exaggerated and unjustified. We believe this to be true for other low incidence countries as well.</p

High source levels and small active space of high-pitched song in bowhead whales (Balaena mysticetus)

© The Author(s), 2012. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Public Library of Science, doi:10.1371/journal.pone.0052072.The low-frequency, powerful vocalizations of blue and fin whales may potentially be detected by conspecifics across entire ocean basins. In contrast, humpback and bowhead whales produce equally powerful, but more complex broadband vocalizations composed of higher frequencies that suffer from higher attenuation. Here we evaluate the active space of high frequency song notes of bowhead whales (Balaena mysticetus) in Western Greenland using measurements of song source levels and ambient noise. Four independent, GPS-synchronized hydrophones were deployed through holes in the ice to localize vocalizing bowhead whales, estimate source levels and measure ambient noise. The song had a mean apparent source level of 185±2 dB rms re 1 µPa @ 1 m and a high mean centroid frequency of 444±48 Hz. Using measured ambient noise levels in the area and Arctic sound spreading models, the estimated active space of these song notes is between 40 and 130 km, an order of magnitude smaller than the estimated active space of low frequency blue and fin whale songs produced at similar source levels and for similar noise conditions. We propose that bowhead whales spatially compensate for their smaller communication range through mating aggregations that co-evolved with broadband song to form a complex and dynamic acoustically mediated sexual display.This work was funded by the Oticon Foundation (grant # 08-3469 to Arctic Station, OT). OT and MC were additionally funded by AP Møller og Hustru Chastine Mc-Kinney Møllers Fond til almene Formaal, MS by a PhD scholarship from the Oticon Foundation, FHJ by a Danish Council for Independent Research, Natural Sciences post-doctoral grant, SEP by a grant from the U.S. Office of Naval Research, and PTM by frame grants from the Danish Natural Science Research Council