491 research outputs found

    Poly[tetra­aqua-di-μ4-malonato-barium(II)cadmium(II)]

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    In the title complex, [BaCd(C3H2O4)2(H2O)4]n, the BaII atoms, located on crystallographic twofold axes, adopt slightly distorted square-anti­prismatic coordination geometries, while the CdII atoms, which lie on crystallographic centres of symmetry, have a distorted octa­hedral coordination. Each malonate dianion binds two different CdII atoms and two different BaII atoms. This connectivity generates alternating layers along [100] in the structure, with one type containing CdII cations and malonate dianions, while the other is primarily composed of BaII ions and coordinated water mol­ecules. The water mol­ecules also participate in extensive O—H⋯O hydrogen bonding

    Realization of Zero-Refractive-Index Lens with Ultralow Spherical Aberration

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    Optical complex materials offer unprecedented opportunity to engineer fundamental band dispersion which enables novel optoelectronic functionality and devices. Exploration of photonic Dirac cone at the center of momentum space has inspired an exceptional characteristic of zero-index, which is similar to zero effective mass in fermionic Dirac systems. Such all-dielectric zero-index photonic crystals provide an in-plane mechanism such that the energy of the propagating waves can be well confined along the chip direction. A straightforward example is to achieve the anomalous focusing effect without longitudinal spherical aberration, when the size of zero-index lens is large enough. Here, we designed and fabricated a prototype of zero-refractive-index lens by comprising large-area silicon nanopillar array with plane-concave profile. Near-zero refractive index was quantitatively measured near 1.55 um through anomalous focusing effect, predictable by effective medium theory. The zero-index lens was also demonstrated to perform ultralow longitudinal spherical aberration. Such IC compatible device provides a new route to integrate all-silicon zero-index materials into optical communication, sensing, and modulation, and to study fundamental physics on the emergent fields of topological photonics and valley photonics.Comment: 14 pages, 4 figure

    Restoring Images Captured in Arbitrary Hybrid Adverse Weather Conditions in One Go

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    Adverse conditions typically suffer from stochastic hybrid weather degradations (e.g., rainy and hazy night), while existing image restoration algorithms envisage that weather degradations occur independently, thus may fail to handle real-world complicated scenarios. Besides, supervised training is not feasible due to the lack of a comprehensive paired dataset to characterize hybrid conditions. To this end, we have advanced the aforementioned limitations with two tactics: framework and data. First, we present a novel unified framework, dubbed RAHC, to Restore Arbitrary Hybrid adverse weather Conditions in one go. Specifically, our RAHC leverages a multi-head aggregation architecture to learn multiple degradation representation subspaces and then constrains the network to flexibly handle multiple hybrid adverse weather in a unified paradigm through a discrimination mechanism in the output space. Furthermore, we devise a reconstruction vectors aided scheme to provide auxiliary visual content cues for reconstruction, thus can comfortably cope with hybrid scenarios with insufficient remaining image constituents. Second, we construct a new dataset, termed HAC, for learning and benchmarking arbitrary Hybrid Adverse Conditions restoration. HAC contains 31 scenarios composed of an arbitrary combination of five common weather, with a total of ~316K adverse-weather/clean pairs. Extensive experiments yield superior results and establish new state-of-the-art results on both HAC and conventional datasets.Comment: In submissio

    Fibroblast Growth Factor 2 Modulates Hippocampal Microglia Activation in a Neuroinflammation Induced Model of Depression

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    Recent studies indicate that disturbed structure and function of microglia can cause depression and associated neurogenesis impairments. Our previous work has demonstrated that exogenous fibroblast growth factor 2 (FGF2) reverses the depressive-like behaviors and the impaired hippocampal neurogenesis in a neuroinflammatory model of depression. However, whether and how the antidepressant effects of FGF2 involve the modulation of microglia activation has not been elucidated. In this study, to examine the effects of FGF2 on microglia activation, exogenous FGF2 was supplemented to the lateral ventricle of rats during the neuroinflammatory state induced by central lipopolysaccharides (LPS) administrations. It was found that FGF2 infusions reversed the LPS-induced depressive-like behaviors and inhibited the hippocampal microglia activation. In LPS-treated rats, FGF2 decreased the level of pro-inflammatory cytokines including interlukin-1β (IL-1β), IL-6 and tumor necrosis factor (TNF)-α, increased the level of IL-10, the anti-inflammatory cytokine and reversed the decreased expression of CX3CL1, a chemokine mainly expressed by neurons and keeping microglia in surveillance. Further, we examined the effects of inhibited FGF2 signaling by administration of SU5402, an FGFR inhibitor. It was found that SU5402 itself evoked depressive-like behaviors, induced microglia activation, increased production of pro-inflammatory cytokines including IL-1β, IL-6 and TNF-α, and decreased the expression of CX3CL1. Two lines of results that FGF2 signaling and FGFR inhibitor can effectively but oppositely modulate the regulation of microglia and the generation of depressive-like behavior, suggesting that microglia-regulated mechanisms may underlie the antidepressant role of FGF2. The present data provide novel insights into the understanding of mechanism of neuroinflammation-associated depression and may serve as a novel mechanism-based target for the treatment of inflammation-related depression

    Community-onset bacteremia in kidney transplant recipients: The recipients fare well in terms of mortality and kidney injury

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    BackgroundBloodstream infection is not uncommon in kidney transplant recipients (KTRs) and is associated with mortality, graft loss, and increased medical expenses. Whether these septic patients are more vulnerable to serious complications, resistant strains, or worse clinical outcomes than other patient groups in the community-onset settings remains undetermined.MethodsA retrospective study was conducted at a medical center in southern Taiwan. Community-onset bacteremia in the KTRs and a control population at the emergency department were identified. Demographic data, clinical characteristics, bacteremic pathogens, antimicrobial resistance, and clinical outcomes were recorded.ResultsForty-one bacteremic episodes in the KTRs and 82 episodes in control patients were studied. The KTR group had younger age, fewer malignancies, more urosepsis (61% vs. 22%, p = 0.004), and fewer biliary tract infections (0% vs. 13.4%, p = 0.018). Escherichia coli was the most commonly isolated pathogen in both the groups (51.2% and 41.5%, respectively). No Klebsiella pneumoniae bacteremia was noted in the KTRs, compared with 14 (17.1%) episodes in the control group (p = 0.010). Antimicrobial resistance profiles of bacteremic pathogens were similar (all p > 0.6). The KTRs with community-onset bacteremia did not have a worse outcome (in-hospital mortality rate: 2.4% vs. 10%, p = 0.172) nor more incomplete resolution of kidney injury after acute kidney injury events (21.1% vs. 25%, p > 0.99) than the control group.ConclusionKTRs with community-onset bacteremia did not fare worse in terms of clinical outcome and kidney injury

    Ultra-short, repetitively pulsed atmospheric-pressure microplasmas

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    Low‐temperature atmospheric‐pressure plasmas are of great importance in many emerging biomedical and materials processing applications; in recent years there has been a growing interest in short‐pulsed excitation of such plasmas as a gateway to access highly non‐equilibrium discharge chemistry. This contribution employs time‐resolved electrical and optical diagnostics in combination with a time‐hybrid computational model to uncover the physics behind repetitive short pulsed excitation of atmospheric pressure plasma. It is shown that during the applied voltage pulse the peak dissipated power can exceed 1GW/cm3 resulting in electron densities approaching 1017 cm‐3 (~6 orders of magnitude larger than conventional low‐temperature atmospheric discharges) while the gas temperature remains close to room temperature
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