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Conjugated microporous polymers based on N,N,N′,N′-tetraphenyl-1,4-phenylenediamine exhibit ultrahigh iodine vapor uptake and good CO2 adsorption.

Basin-fill aquifers of the Southwestern United States are associated with elevated concentrations of arsenic (As) in groundwater. Many private domestic wells in the Cache Valley Basin, UT, have As concentrations in excess of the U.S. EPA drinking water limit. Thirteen sediment cores were collected from the center of the valley at the depth of the shallow groundwater and were sectioned into layers based on redoxmorphic features. Three of the layers, two from redox transition zones and one from a depletion zone, were used to establish microcosms. Microcosms were treated with groundwater (GW) or groundwater plus glucose (GW؉G) to investigate the extent of As reduction in relation to iron (Fe) transformation and characterize the microbial community structure and function by sequencing 16S rRNA and arsenate dissimilatory reductase (arrA) genes. Under the carbon-limited conditions of the GW treatment, As reduction was independent of Fe reduction, despite the abundance of sequences related to Geobacter and Shewanella, genera that include a variety of dissimilatory iron-reducing bacteria. The addition of glucose, an electron donor and carbon source, caused substantial shifts toward domination of the bacterial community by Clostridium-related organisms, and As reduction was correlated with Fe reduction for the sediments from the redox transition zone. The arrA gene sequencing from microcosms at day 54 of incubation showed the presence of 14 unique phylotypes, none of which were related to any previously described arrA gene sequence, suggesting a unique community of dissimilatory arsenate-respiring bacteria in the Cache Valley Basin.A rsenic (As) is one of the most frequently detected contaminants in private domestic wells used for household drinking water (1) and public water supplies (2). In the United States, As concentrations in excess of the drinking water maximum contaminant level (MCL; 10 g/liter) in public supply wells are distributed across the country, but 3/4 of these wells are in the western United States (2). In basin-fill aquifers in California, Nevada, New Mexico, Arizona (1), and Utah (3), 10% of the domestic wells tested had As in excess of the MCL. Modeling efforts by the USGS predicted that 43% of the area in the basin-fill aquifers of the Southwest might have groundwater that equals or exceeds the MCL for As (4). While public water suppliers are required to treat water to meet drinking water standards, there are no such requirements for private wells.Common aspects of the basin-fill aquifers in the western United States are geothermal activity and volcanic rock. The source of As in the Cache Valley Basin, UT, is presumed to be the hydrothermal sulfide and arsenide deposits in the surrounding mountains. Due to low rainfall and high evapotranspiration, groundwater recharge does not result from precipitation in the basin but from precipitation in the surrounding mountains. The Cache Valley Basin is located 128 km northeast of Salt Lake City and is on the eastern edge of the Basin and Range Province. A sur...

Divergent syntheses of indolizines and 2,4-disubstituted pyrroles by the silver-catalyzed cyclization of 2-pyridyl alkynyl carbinols with isocyanides are reported.

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Construction of porous organic polymers (POPs) with high surface areas,well-defined nanopores,and excellent stability remains extremely challenging because of the unmanageable reaction process.Until now, only afew reported POPs have Brunauer-Emmett-Teller (BET) surface areas (S BET) exceeding 3000 m 2 g À1 .H erein, we demonstrate am olecular expansion strategy to integrate high surface areas,l arge nanopore sizes,a nd outstanding stability into POPs.Aseries of hyper-crosslinked conjugated polymers (HCCPs)w ith exceptional porosity are synthesized through this strategy. Specially, HCCP-6 and HCCP-11 exhibit the highest surface areas (S BET > 3000 m 2 g À1)and excellent total pore volumes (up to 3.98 cm 3 g À1)among these HCCPs.They present decent total CH 4 storage capacities of 491 and 421 mg g À1 at 80 bar and 298 K, respectively.Meanwhile,they are highly stable in harsh environments.T he facile and general molecular expansion strategy would lead to improved synthetic routes of POPs for desired functions.

BackgroundThe emergence and spread of Carbapenem-resistant Escherichia coli (CREC) is becoming a serious problem in Chinese hospitals, however, the data on this is scarce. Therefore, we investigate the risk factors for healthcare-associated CREC infection and study the incidence, antibiotic resistance and medical costs of CREC infections in our hospital.MethodsWe conducted a retrospective, matched case–control–control, parallel study in a tertiary teaching hospital. Patients admitted between January 2012 and December 2015 were included in this study. For patients with healthcare-associated CREC infection, two matched subject groups were created; one group with healthcare-associated CSEC infection and the other group without infection.ResultsMultivariate conditional logistic regression analysis demonstrated that prior hospital stay (<6 months) (OR:3.96; 95%CI:1.26–12.42), tracheostomy (OR:2.24; 95%CI: 1.14–4.38), central venous catheter insertion (OR: 8.15; 95%CI: 2.31–28.72), carbapenem exposure (OR: 12.02; 95%CI: 1.52–95.4), urinary system disease (OR: 16.69; 95%CI: 3.01–89.76), low hemoglobin (OR: 2.83; 95%CI: 1.46–5.50), and high blood glucose are associated (OR: 7.01; 95%CI: 1.89–26.02) with CREC infection. Total costs (p = 0.00), medical examination costs (p = 0.00), medical test costs (p = 0.00), total drug costs (p = 0.00) and ant-infective drug costs (p = 0.00) for the CREC group were significantly higher than those for the no infection group. Medical examination costs (p = 0.03), total drug costs (p = 0.03), and anti-infective drug costs (p = 0.01) for the CREC group were significantly higher than for the CSEC group. Mortality in CREC group was significantly higher than the CSEC group (p = 0.01) and no infection group (p = 0.01).ConclusionMany factors were discovered for acquisition of healthcare-associated CREC infection. CREC isolates were resistant to most antibiotics, and had some association with high financial burden and increased mortality.