An Overview of Regional Experiments on Biomass Burning Aerosols and Related Pollutants in Southeast Asia: From BASE-ASIA and the Dongsha Experiment to 7-SEAS

By modulating the Earth-atmosphere energy, hydrological and biogeochemical cycles, and affecting regional-to-global weather and climate, biomass burning is recognized as one of the major factors affecting the global carbon cycle. However, few comprehensive and wide-ranging experiments have been conducted to characterize biomass-burning pollutants in Southeast Asia (SEA) or assess their regional impact on meteorology, the hydrological cycle, the radiative budget, or climate change. Recently, BASEASIA (Biomass-burning Aerosols in South-East Asia: Smoke Impact Assessment) and the 7-SEAS (7- South-East Asian Studies) Dongsha Experiment were conducted during the spring seasons of 2006 and 2010 in northern SEA, respectively, to characterize the chemical, physical, and radiative properties of biomass-burning emissions near the source regions, and assess their effects. This paper provides an overview of results from these two campaigns and related studies collected in this special issue, entitled Observation, modeling and impact studies of biomass burning and pollution in the SE Asian Environment. This volume includes 28 papers, which provide a synopsis of the experiments, regional weatherclimate, chemical characterization of biomass-burning aerosols and related pollutants in source and sink regions, the spatial distribution of air toxics (atmospheric mercury and dioxins) in source and remote areas, a characterization of aerosol physical, optical, and radiative properties, as well as modeling and impact studies. These studies, taken together, provide the first relatively complete dataset of aerosol chemistry and physical observations conducted in the sourcesink region in the northern SEA, with particular emphasis on the marine boundary layer and lower free troposphere (LFT). The data, analysis and modeling included in these papers advance our present knowledge of source characterization of biomass-burning pollutants near the source regions as well as the physical and chemical processes along transport pathways. In addition, we raise key questions to be addressed by a coming deployment during springtime 2013 in northern SEA, named 7-SEASBASELInE (Biomass-burning Aerosols Stratocumulus Environment: Lifecycles and Interactions Experiment). This campaign will include a synergistic approach for further exploring many key atmospheric processes (e.g., complex aerosol-cloud interactions) and impacts of biomass burning on the surface-atmosphere energy budgets during the lifecycles of biomass burning emissions

Coronavirus Gene 7 Counteracts Host Defenses and Modulates Virus Virulence

Transmissible gastroenteritis virus (TGEV) genome contains three accessory genes: 3a, 3b and 7. Gene 7 is only present in members of coronavirus genus a1, and encodes a hydrophobic protein of 78 aa. To study gene 7 function, a recombinant TGEV virus lacking gene 7 was engineered (rTGEV-Δ7). Both the mutant and the parental (rTGEV-wt) viruses showed the same growth and viral RNA accumulation kinetics in tissue cultures. Nevertheless, cells infected with rTGEV-Δ7 virus showed an increased cytopathic effect caused by an enhanced apoptosis mediated by caspase activation. Macromolecular synthesis analysis showed that rTGEV-Δ7 virus infection led to host translational shut-off and increased cellular RNA degradation compared with rTGEV-wt infection. An increase of eukaryotic translation initiation factor 2 (eIF2α) phosphorylation and an enhanced nuclease, most likely RNase L, activity were observed in rTGEV-Δ7 virus infected cells. These results suggested that the removal of gene 7 promoted an intensified dsRNA-activated host antiviral response. In protein 7 a conserved sequence motif that potentially mediates binding to protein phosphatase 1 catalytic subunit (PP1c), a key regulator of the cell antiviral defenses, was identified. We postulated that TGEV protein 7 may counteract host antiviral response by its association with PP1c. In fact, pull-down assays demonstrated the interaction between TGEV protein 7, but not a protein 7 mutant lacking PP1c binding motif, with PP1. Moreover, the interaction between protein 7 and PP1 was required, during the infection, for eIF2α dephosphorylation and inhibition of cell RNA degradation. Inoculation of newborn piglets with rTGEV-Δ7 and rTGEV-wt viruses showed that rTGEV-Δ7 virus presented accelerated growth kinetics and pathology compared with the parental virus. Overall, the results indicated that gene 7 counteracted host cell defenses, and modified TGEV persistence increasing TGEV survival. Therefore, the acquisition of gene 7 by the TGEV genome most likely has provided a selective advantage to the virus

Multi-messenger observations of a binary neutron star merger

On 2017 August 17 a binary neutron star coalescence candidate (later designated GW170817) with merger time 12:41:04 UTC was observed through gravitational waves by the Advanced LIGO and Advanced Virgo detectors. The Fermi Gamma-ray Burst Monitor independently detected a gamma-ray burst (GRB 170817A) with a time delay of ~1.7 s with respect to the merger time. From the gravitational-wave signal, the source was initially localized to a sky region of 31 deg2 at a luminosity distance of 40+8-8 Mpc and with component masses consistent with neutron stars. The component masses were later measured to be in the range 0.86 to 2.26 Mo. An extensive observing campaign was launched across the electromagnetic spectrum leading to the discovery of a bright optical transient (SSS17a, now with the IAU identification of AT 2017gfo) in NGC 4993 (at ~40 Mpc) less than 11 hours after the merger by the One- Meter, Two Hemisphere (1M2H) team using the 1 m Swope Telescope. The optical transient was independently detected by multiple teams within an hour. Subsequent observations targeted the object and its environment. Early ultraviolet observations revealed a blue transient that faded within 48 hours. Optical and infrared observations showed a redward evolution over ~10 days. Following early non-detections, X-ray and radio emission were discovered at the transient’s position ~9 and ~16 days, respectively, after the merger. Both the X-ray and radio emission likely arise from a physical process that is distinct from the one that generates the UV/optical/near-infrared emission. No ultra-high-energy gamma-rays and no neutrino candidates consistent with the source were found in follow-up searches. These observations support the hypothesis that GW170817 was produced by the merger of two neutron stars in NGC4993 followed by a short gamma-ray burst (GRB 170817A) and a kilonova/macronova powered by the radioactive decay of r-process nuclei synthesized in the ejecta

Iron Behaving Badly: Inappropriate Iron Chelation as a Major Contributor to the Aetiology of Vascular and Other Progressive Inflammatory and Degenerative Diseases

The production of peroxide and superoxide is an inevitable consequence of aerobic metabolism, and while these particular "reactive oxygen species" (ROSs) can exhibit a number of biological effects, they are not of themselves excessively reactive and thus they are not especially damaging at physiological concentrations. However, their reactions with poorly liganded iron species can lead to the catalytic production of the very reactive and dangerous hydroxyl radical, which is exceptionally damaging, and a major cause of chronic inflammation. We review the considerable and wide-ranging evidence for the involvement of this combination of (su)peroxide and poorly liganded iron in a large number of physiological and indeed pathological processes and inflammatory disorders, especially those involving the progressive degradation of cellular and organismal performance. These diseases share a great many similarities and thus might be considered to have a common cause (i.e. iron-catalysed free radical and especially hydroxyl radical generation). The studies reviewed include those focused on a series of cardiovascular, metabolic and neurological diseases, where iron can be found at the sites of plaques and lesions, as well as studies showing the significance of iron to aging and longevity. The effective chelation of iron by natural or synthetic ligands is thus of major physiological (and potentially therapeutic) importance. As systems properties, we need to recognise that physiological observables have multiple molecular causes, and studying them in isolation leads to inconsistent patterns of apparent causality when it is the simultaneous combination of multiple factors that is responsible. This explains, for instance, the decidedly mixed effects of antioxidants that have been observed, etc...Comment: 159 pages, including 9 Figs and 2184 reference

The Numerical Simulation of Optimal Design in Target Tracker by α-β-γ-δ Filter

[[abstract]]摘要 就現代而言，無論是軍事上，民間上，目標追蹤是非常重要之研究項目，且可以廣泛應用。國內外研究人員提出很多數學模式應用於目標追蹤系統。而α-β filter 及α-β-γ filter很早就用來處理這方面之問題。其計算簡單，速度快，很適合快速跟蹤之濾波器。如果要再提升精確度，且能更適用於目標變動大或多目標及複雜之情況，本論文提出改善之方法，其主要研究結果如下： 1 在α-β-γ filter加入一個新的參數值δ，稱為jerk，其為加速度對時間之微分值，成為新的α-β-γ-δ filter，其結果使誤差減少，可獲得更好的精確度。 2 在新的α-β-γ-δ filter，有效提升精確度，但因多一參數值δ，造成需要較大之運算時間，為了改善此缺點，本論文再應用基因演算法(Genetic Algorithm GA)方法，形成GA-based α-β-γ-δ filter，證實除了精確度改善外，計算時間亦縮短。 3 上述本論文，是以GA方法探討，另外，進一步合併兩種啟發性方法，一為GA方法，另一為田口式方法(Taguchi method)，其效果證實誤差可以再減低而提升其追蹤精確度。 4 除了GA方法證明其可行性，本論文同時改用進化式計算另一種進化式規劃方法(Evolutionary Programming EP)，成為EP-based α-β-γ-δ filter，亦同樣得到精確度改善及計算時間縮短。也證明除了GA方法外，EP方法亦可行，將來亦可以其他方法求最佳化來進一步探討。 5 本論文以同樣之例題，比較GA-based α-β-γ-δ filter與α-β-γ filter之誤差與EP-based α-β-γ-δ filter和α-β-γ filter之誤差很相近，証實GA與EP均有相同改善之效果，因此，相信其他啟發性方法亦可獲得良好之精確度。 6 本論文主要是目標追蹤之數值模擬，且未探討噪音問題，因此，距實際應用仍有一段距離，倘若能克服噪音，相信將來可以實際嘗試應用於全方位機器人、工程方面、交通管制、及產業生產方面之範圍。 關鍵字：目標追蹤；基因演算法；α-β-γ-δ 過濾器；α-β-γ 過濾器； GA-based α-β-γ-δ過濾器；進化式規劃方法；EP-based α-β-γ-δ過濾器[[abstract]]Abstract In modern tracking analysis many researchers have attempted the various models of the target tracking process General target tracking is the important problem in military and civilian fields Many mathematical models have been formulated to manipulate the target tracking system in the world In the mid 1950’s relatively simple α-β and α-β-γ filter trackers were developed to deal with this problem Their advantages are simple computation and quick response when target maneuvering Nevertheless it is to be more adaptable under complicated situation in multi-target tracking or changeable target The achievements of the dissertation are as follows: 1 To further predict the acceleration and improve the tracking accuracy an additional state value called jerk that is time derivative of acceleration will need to be observed As a result it exhibits significant improvement in tracking accuracy over the α-β-γ filter 2 Not unexpectedly however the new α-β-γ-δ filter takes more computation time in the optimization process To overcome this weakness an optimal simulation technique via Genetic Algorithm (GA) is proposed The developed GA-based α-β-γ-δ filter finds not only the optimal set of filter parameters to minimize position tracking errors but could also reduce the computation time in some time steps 3 Besides two heuristic methods (one is GA method the other is Taguchi method ) are combined together for improving tracking accuracy Finally the result shows it leads to get more tracking accuracy 4 Furthermore the Evolutionary Programming (EP) algorithm is then introduced As a result the developed EP-based α-β-γ-δ filter also finds not only the optimal set of filter parameters to minimize position tracking errors but could also reduce the computation time 5 In this paper it is also to compare the tracking accuracy between GA-based α-β-γ-δ filter and EP-based α-β-γ-δ filter The result shows the same tracking accuracy 6 The applications of others shall be explored in future As above mention another algorithm method can be explored in target tracking process for optimization in future Keywords: target tracker; Genetic Algorithm; the α-β-γ-δ filter; the α-β-γ filter; the GA-based α-β-γ-δ filter; Evolutionary Programming; the EP-based α-β-γ-δ filte

Synthesis of Ni-Doped ZnO Nanorod Arrays by Chemical Bath Deposition and Their Application to Nanogenerators

Nanogenerators (NGs) based on Ni-doped ZnO (NZO) nanorod (NR) arrays were fabricated and explored in this study. The ZnO films were grown on indium tin oxide (ITO) glass substrates, and the NZO NRs were prepared by the chemical bath deposition (CBD) method. The samples were investigated via field-emission scanning electron microscopy (FE-SEM) and X-ray diffraction (XRD) spectral analysis. The results showed that the growth of NRs presented high-density single crystalline structures and were preferentially oriented in the c-axis direction. The optical characteristics of the NZO NRs were also measured by photoluminescence (PL) spectra. All samples exhibited two different emissions, including ultraviolet (UV) and green emissions. ITO etching paste was used to define patterns, and an electrode of Au film was evaporated onto the ITO glass substrates by the electron beam evaporation technique to assemble the NG device. In summary, ZnO NRs with Ni dopant (5 mM) showed significantly excellent performance in NGs. The optimal measured voltage, current, and power for the fabricated NGs were 0.07 V, 10.5 µA, and 735 nW, respectively

Fabrication of Ultraviolet Photodetectors Based on Fe-Doped ZnO Nanorod Structures

In this paper, 100 nm-thick zinc oxide (ZnO) films were deposited as a seed layer on Corning glass substrates via a radio frequency (RF) magnetron sputtering technique, and vertical well-aligned Fe-doped ZnO (FZO) nanorod (NR) arrays were then grown on the seed layer-coated substrates via a low-temperature solution method. FZO NR arrays were annealed at 600 °C and characterized by using field emission scanning microscopy (FE-SEM) and X-ray diffraction spectrum (XRD) analysis. FZO NRs grew along the preferred (002) orientation with good crystal quality and hexagonal wurtzite structure. The main ultraviolet (UV) peak of 378 nm exhibited a red-shifted phenomenon with Fe-doping by photoluminescence (PL) emission. Furthermore, FZO photodetectors (PDs) based on metal–semiconductor–metal (MSM) structure were successfully manufactured through a photolithography procedure for UV detection. Results revealed that compared with pure ZnO NRs, FZO NRs exhibited a remarkable photosensitivity for UV PD applications and a fast rise/decay time. The sensitivities of prepared pure ZnO and FZO PDs were 43.1, and 471.1 for a 3 V applied bias and 380 nm UV illumination, respectively

Chinese MARC: Its Present Status and Future Development

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