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Increasing evidence indicates that immunotherapy is hindered by a hostile tumor microenvironment (TME) featured with deprivation of critical nutrients and pooling of immunosuppressive metabolites. Tumor cells and immunosuppressive cells outcompete immune effector cells for essential nutrients. Meanwhile, a wide range of tumor cell-derived toxic metabolites exerts negative impacts on anti-tumor immune response, diminishing the efficacy of immunotherapy. Nanomedicine with excellent targetability offers a novel approach to improving cancer immunotherapy via metabolically reprogramming the immunosuppressive TME. Herein, we review recent strategies of enhancing immunotherapeutic effects through rewiring tumor metabolism via nanomedicine. Attention is drawn on immunometabolic tactics for immune cells and stromal cells in the TME via nanomedicine. Additionally, we discuss future directions of developing metabolism-regulating nanomedicine for precise and efficacious cancer immunotherapy.

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A challenge in the application of two-dimensional (2D) SnS in gas-sensing field is that the SnS monolayer is highly sensitive to oxidizing gases, whereas it is naturally deactivated towards reducing gases. The non-sensitivity of SnS to reducing gases is a problem that needs to be solved urgently in an economic and effective manner. Hence, in this work, we propose a strategy of applying strain modulation on the SnS monolayer to optimize its sensitivity and selectivity for reducing gases fundamentally. Generally, the strain modulation applied on a semiconductor gives rise to a change in its band gap (BG). Based on the first-principles calculations, the strain on SnS was found to induce strong degeneracy and energy-level splitting. Unusually, the tensile strain (≥3%) applied could transform the SnS monolayer from indirect-gap semiconductors to direct-gap semiconductors, manifesting a promising optical application prospect but not appropriate for the gas-sensing filed. Comparatively, the compressive strain (≥3%) on SnS could generate new electronic states at the edge of the conduction band of the SnS monolayer, which increases the conductivity and the weak interaction. Thus, the adsorption of reducing gases on the SnS monolayer is enhanced from physisorption to chemisorption, resulting in a considerable increase in the sensitivity performance to the three reducing gas molecules (NH3, H2S, and CO). The induced symmetry breaking of the SnS monolayer under compressive strain leads to much higher surface activation towards reducing gases, which improves its adsorption capability and the ability of screening oxidizing gas molecules. The present work provides key information for novel designs of strain-sensitive dual-function sensors based on SnS.

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Two-dimensional group-IV monochalcogenides MX (M = Ge, and Sn; X = S, and Se) are explored for their potential in gas-sensing applications. In this work, a combined theoretical and experimental study on pure SnS and Zn-substituted SnS for promising methanol sensors is performed. The adsorption characteristics of methanol on pure and Zn-substituted SnS were first calculated using first-principles based on density functional theory (DFT). It is clarified theoretically that the incorporation of Zn dopant could enhance the adsorption capability of the SnS surface to methanol molecules, thus achieving obvious response enhancement and selectivity improvement. Further experimental investigation is carried out based on the successful synthesis of pure and Zn-substituted SnS with hierarchical architecture via a one-step solvothermal process. Gas-sensing measurement indicates that the Zn-substituted SnS sensor is promising for selective detection of rarefied methanol. At room temperature, the as-synthesized hierarchical SnS with an appropriate amount of Zn-doping can sense methanol vapor of as low as 100 ppb. In particular, Zn-doping can enhance the sensing response of methanol significantly, with a 32.8-fold increase in response value achieved in comparison to that of the pure SnS. The underlying mechanism for the response enhancement of Zn-substituted SnS is also analyzed and demonstrated in detail. The present work demonstrates that Zn-doping is highly effective for improving the response and selectivity of SnS towards methanol vapor, and the Zn-substituted SnS is promising for highly sensitive methanol sensors with low consumption.

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An acceleration sensor based on piezoelectric thin films is proposed in this paper, which comprises the elastic element of a silicon cantilever beam and a piezoelectric structure with Li-doped ZnO piezoelectric thin films. The Li-doped ZnO piezoelectric thin films were prepared on SiO2/Si by radio frequency (RF) magnetron sputtering method. The microstructure and micrograph of ZnO piezoelectric thin films is analysed by a X-ray diffractometer (XRD), scanning electron microscope (SEM), X-ray photoelectron spectroscopy (XPS), and piezoresponse force microscopy (PFM), respectively. When the sputtering power of 220 W and Li-doped concentration of 5%, ZnO piezoelectric thin films have a preferred (002) orientation. The chips of the sensor were fabricated on the <100> silicon substrate by micro-electromechanical systems (MEMS) technology, meanwhile, the proposed sensor was packaged on the printed circuit board (PCB). The experimental results show the sensitivity of the proposed sensor is 29.48 mV/g at resonant frequency (1479.8 Hz).

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BACKGROUND: The purpose of this systematic review was to evaluate the effect of magnesium sulfate in the treatment of acute traumatic brain injury. MATERIALS AND METHODS: A systematic search of ClinicalTrials.gov, the Cochrane Library database, EMBASE, MEDLINE, Web of Science, and the World Health Organization trial registry, plus manual searches of gray literature, was undertaken in April 2013. Two reviewers independently extracted the data with a predefined data extraction form. RevMan 5 software was used to synthesize data and calculate the risk ratio for mortality with the 95% confidence interval. For the Glasgow Outcome Scale and posttreatment Glasgow Coma Scale data, the weighted mean difference was calculated with the 95% confidence interval. RESULTS: A total of 8 randomized controlled trials with a total of 786 patients were included. Meta-analysis showed that there was no significant difference between the groups for mortality. The Glasgow Outcome Scale of the treatment group was higher than that of the control group, although the significance was borderline. The Glasgow Coma Scale score change posttreatment was significantly higher than that of the control. CONCLUSIONS: The present meta-analysis of existing randomized controlled trials does not identify a significant beneficial effect in the mortality of traumatic brain injury patients; however, it suggests that magnesium sulfate shows a tendency to improve the Glasgow Outcome Scale and Glasgow Coma Scale scores, which is a promising result for traumatic brain injury therapy. Further effort is necessary to explore which subgroup of traumatic brain injury patients could benefit from magnesium sulfate.

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Remote epidural hematoma (REDH) is an uncommon complication of decompressive craniectomy. Remote epidural hematomas of the parietal occiput region have been reported only rarely. We report a unique case of delayed-onset bilateral extensive straddle postsagittal sinus and bilateral lateral sinus parietal occiput REDH after decompressive craniectomy, of which volume was approximately 130 mL, with left deviating midline structures. The patient was immediately taken back to the operating room for evacuation of the REDH via bilateral parietal and occiput craniectomy. Postoperatively, serial computed tomographic scans performed 3 days later showed that the REDH had been completely evacuated. Two months later, the patient regained full consciousness and obtained a near-complete recovery except for right facial paralysis.

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The purpose of this systematic review was to evaluate and meta-analyse the current evidence for the use of calcium channel blockers (CCBs) in the treatment of acute traumatic brain injury (TBI) and traumatic subarachnoid haemorrhage (tSAH). A systematic search of clinical trials.gov, Cochrane library databases, EMBASE, MEDLINE, Web of science search and WHO trial registry, plus hand-searching of grey literature, was undertaken in March 2013. Two reviewers independently extracted the data using a pre-defined data extraction form. RevMan 5 software was used to synthesise data and calculate the risk ratio (RR) based on event rates as well as the 95% confidence interval (CI). Finally, nine RCTs with a total of 2182 patients were included. Meta-analysis showed that there was no difference between CCBs and control groups for rates of mortality (n=1337, 5 RCTs, RR 0.93 CI 0.77-1.12). In a subgroup tSAH analysis, the difference was not significant (n=389, 2 RCTs, RR 0.73 CI 0.53-1.02). There were slightly fewer unfavourable outcomes in the treatment group, but the difference was not statistically significant (n=2101, 8 RCTs, RR 0.90 CI 0.76-1.08). In the subgroup tSAH analysis, again, the difference did not reach statistical significance (n=1074, 5 RCTs, RR 0.95 CI 0.73-1.24). It seems that larger, well-designed RCTs are necessary in order to ascertain any clinical benefit CCBs may or may not have for the treatment of acute TBI.

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