Applicability of an integrated moving sponge biocarrier-osmotic membrane bioreactor MD system for saline wastewater treatment using highly salt-tolerant microorganisms

© 2017 Elsevier B.V. Osmotic membrane bioreactors (OsMBRs) are a recent breakthrough technology designed to treat wastewater. Nevertheless, their application in high-salinity wastewater treatment is not widespread because of the effects of saline conditions on microbial community activity. In response, this study developed an integrated sponge biocarrier-OsMBR system using highly salt-tolerant microorganisms for treating saline wastewater. Results showed that the sponge biocarrier-OsMBR obtained an average water flux of 2 L/m2 h during a 92-day operation when 1 M MgCl2 was used as the draw solution. The efficiency in removing dissolved organic compounds from the proposed system was more than 99%, and nutrient rejection was close to 100%, indicating excellent performance in simultaneous nitrification and denitrification processes in the biofilm layer on the carriers. Moreover, salt-tolerant microorganisms in the sponge biocarrier-OsMBR system worked efficiently in salt concentrations of 2.4%. A polytetrafluoroethylene MD membrane (pores = 0.45 μm) served to regenerate the diluted draw solution in the closed-loop system and produce high-quality water. The moving sponge biocarrier-OsMBR/MD hybrid system demonstrated its potential to treat salinity wastewater treatment, with 100% nutrient removal and 99.9% conductivity rejection

Orbital textures and charge density waves in transition metal dichalcogenides

Low-dimensional electron systems, as realized naturally in graphene or created artificially at the interfaces of heterostructures, exhibit a variety of fascinating quantum phenomena with great prospects for future applications. Once electrons are confined to low dimensions, they also tend to spontaneously break the symmetry of the underlying nuclear lattice by forming so-called density waves; a state of matter that currently attracts enormous attention because of its relation to various unconventional electronic properties. In this study we reveal a remarkable and surprising feature of charge density waves (CDWs), namely their intimate relation to orbital order. For the prototypical material 1T-TaS2 we not only show that the CDW within the two-dimensional TaS2-layers involves previously unidentified orbital textures of great complexity. We also demonstrate that two metastable stackings of the orbitally ordered layers allow to manipulate salient features of the electronic structure. Indeed, these orbital effects enable to switch the properties of 1T-TaS2 nanostructures from metallic to semiconducting with technologically pertinent gaps of the order of 200 meV. This new type of orbitronics is especially relevant for the ongoing development of novel, miniaturized and ultra-fast devices based on layered transition metal dichalcogenides

Mild to moderate influenza A(H7N9) infections detected through China’s national influenza-like Illness sentinel surveillance system

Poster Session: News and Views from the H7N9 OutbreakBackground: The “clinical iceberg” phenomenon, where there are usually many more infected cases than is apparent symptomatically and even less so registered in the clinical setting, is a common feature of influenza disease. While this is certainly true for interpandemic influenza and the 2009 influenza A(H1N1) pandemic, this appeared to be less substantial for the Dutch A(H7N7) outbreak, and with A(H5N1) being an acknowledged exception. It remains unknown whether the “iceberg” applies to the influenza A(H7N9) virus that emerged in early 2013 in China. While the majority of laboratory-confirmed A(H7N9) cases presented with a severe clinical picture to a hospital, a small number of laboratory-confirmed cases have been identified through the sentinel influenza-like illness (ILI) surveillance system nationwide. The objective of our study was to describe the clinical characteristics of the complete case series of A(H7N9) cases as of May 15, 2013, that were identified through routine testing by the ILI sentinel surveillance system. Materials and Methods: ILI sentinel surveillance in China is conducted through a network of 554 hospitals across the country, with the total number of outpatient and/or emergency department visits and the number of patients fitting the WHO standard ILI case definition reported weekly online to the China CDC, and 10-15 nasopharyngeal swabs collected from ILI patients each week for routine laboratory testing and subtyping. All A(H7N9) cases detected through the ILI surveillance system by May 15, 2013, were identified by cross-referencing the laboratory-confirmed A(H7N9) line list with the routine sentinel ILI surveillance system. Demographic and epidemiologic data were extracted from field investigation records, and clinical and laboratory data were obtained from medical chart review. Results: Five (3.8%) of a total of 130 laboratory-confirmed influenza A(H7N9) cases reported as of May 28, 2013, were detected through the routine ILI surveillance system. Four (80%) of them were male. Mean age was 13 (range = 2-26) years and none had any underlying medical condition. Exposure history, geographic location and timing of symptom onset were otherwise similar to the general cohort of all laboratory-confirmed cases to date. All patients experienced only mild or moderate disease with an uneventful course of recovery. Among them three (60%) were managed only as outpatients and all quickly recovered after 3-5 days, with nasopharyngeal swabs tested positive for A(H7N9) only after their full recovery. Two patients (40%) were hospitalized for treatment. One was a 4-year-old child from Shanghai who presented initially as an outpatient with fever and mild rhinorrhea to a routine sentinel clinic, and was admitted on the next day for oseltamivir treatment after his nasopharyngeal swab was tested positive for A(H7N9). The other was a 26-year-old man from Jiangsu who presented initially with fever and productive cough to a sentinel clinic, being given ceftazidime without improvement. He was admitted 4 days later with radiologic evidence of left-sided pneumonia, and started on oseltamivir and moxifloxacin. Both remained clinically stable with quick resolution of symptoms within 10 days. Conclusions: Our complete case series of A(H7N9) cases detected through the routine ILI surveillance system provide contrasting clinical presentations to the generally much more severe clinical picture of the majority of laboratory-confirmed A(H7N9) cases detected otherwise. Our findings provide indirect evidence of a substantial proportion of mild disease and support the existence of a “clinical iceberg” phenomenon in influenza A(H7N9) infections. For the clinician, our findings reinforce vigilance to the diverse presentation that can be associated with influenza A(H7N9) virus infections. Our results also suggest that large-scale community surveillance networks can be useful as a population-based sampling tool to enhance understanding of the full spectrum of disease, especially in the early phase of an evolving epidemic.published_or_final_versio

Synthesis and Characterization of Tin Disulfide (SnS2) Nanowires

The ordered tin disulfide (SnS2) nanowire arrays were first fabricated by sulfurizing the Sn nanowires, which are embedded in the nanochannels of anodic aluminum oxide (AAO) template. SnS2nanowire arrays are highly ordered and highly dense. X-ray diffraction (XRD) and corresponding selected area electron diffraction (SAED) patterns demonstrate the SnS2nanowire is hexagonal polycrystalline. The study of UV/Visible/NIR absorption shows the SnS2nanowire is a wide-band semiconductor with three band gap energies (3.3, 4.4, and 5.8 eV)

Detection of mild to moderate influenza A/H7N9 infection by China's national sentinel surveillance system for influenza-like illness: case series

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Results from PAMELA, ATIC and FERMI : Pulsars or Dark Matter ?

It is well known that the dark matter dominates the dynamics of galaxies and clusters of galaxies. Its constituents remain a mystery despite an assiduous search for them over the past three decades. Recent results from the satellite-based PAMELA experiment detect an excess in the positron fraction at energies between 10-100 GeV in the secondary cosmic ray spectrum. Other experiments namely ATIC, HESS and FERMI show an excess in the total electron (\ps + \el) spectrum for energies greater 100 GeV. These excesses in the positron fraction as well as the electron spectrum could arise in local astrophysical processes like pulsars, or can be attributed to the annihilation of the dark matter particles. The second possibility gives clues to the possible candidates for the dark matter in galaxies and other astrophysical systems. In this article, we give a report of these exciting developments.Comment: 27 Pages, extensively revised and significantly extended, to appear in Pramana as topical revie

Localisation of RNAs into the germ plasm of vitellogenic xenopus oocytes

We have studied the localisation of mRNAs in full-grown Xenopus laevis oocytes by injecting fluorescent RNAs, followed by confocal microscopy of the oocyte cortex. Concentrating on RNA encoding the Xenopus Nanos homologue, nanos1 (formerly Xcat2), we find that it consistently localised into aggregated germ plasm ribonucleoprotein (RNP) particles, independently of cytoskeletal integrity. This implies that a diffusion/entrapment-mediated mechanism is active, as previously reported for previtellogenic oocytes. Sometimes this was accompanied by localisation into scattered particles of the “late”, Vg1/VegT pathway; occasionally only late pathway localisation was seen. The Xpat RNA behaved in an identical fashion and for neither RNA was the localisation changed by any culture conditions tested. The identity of the labelled RNP aggregates as definitive germ plasm was confirmed by their inclusion of abundant mitochondria and co-localisation with the germ plasm protein Hermes. Further, the nanos1/Hermes RNP particles are interspersed with those containing the germ plasm protein Xpat. These aggregates may be followed into the germ plasm of unfertilized eggs, but with a notable reduction in its quantity, both in terms of injected molecules and endogenous structures. Our results conflict with previous reports that there is no RNA localisation in large oocytes, and that during mid-oogenesis even germ plasm RNAs localise exclusively by the late pathway. We find that in mid oogenesis nanos1 RNA also localises to germ plasm but also by the late pathway. Late pathway RNAs, Vg1 and VegT, also may localise into germ plasm. Our results support the view that mechanistically the two modes of localisation are extremely similar, and that in an injection experiment RNAs might utilise either pathway, the distinction in fates being very subtle and subject to variation. We discuss these results in relation to their biological significance and the results of others

Enhanced UV photosensitivity from rapid thermal annealed vertically aligned ZnO nanowires

We report on the major improvement in UV photosensitivity and faster photoresponse from vertically aligned ZnO nanowires (NWs) by means of rapid thermal annealing (RTA). The ZnO NWs were grown by vapor-liquid-solid method and subsequently RTA treated at 700°C and 800°C for 120 s. The UV photosensitivity (photo-to-dark current ratio) is 4.5 × 103 for the as-grown NWs and after RTA treatment it is enhanced by a factor of five. The photocurrent (PC) spectra of the as-grown and RTA-treated NWs show a strong peak in the UV region and two other relatively weak peaks in the visible region. The photoresponse measurement shows a bi-exponential growth and bi-exponential decay of the PC from as-grown as well as RTA-treated ZnO NWs. The growth and decay time constants are reduced after the RTA treatment indicating a faster photoresponse. The dark current-voltage characteristics clearly show the presence of surface defects-related trap centers on the as-grown ZnO NWs and after RTA treatment it is significantly reduced. The RTA processing diminishes the surface defect-related trap centers and modifies the surface of the ZnO NWs, resulting in enhanced PC and faster photoresponse. These results demonstrated the effectiveness of RTA processing for achieving improved photosensitivity of ZnO NWs