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Abstract: The purpose of the present study is to identify whether interleukin (IL)-18 can modulate cysteinyl leukotriene 2 receptor (CysLT2R) expression in Human Umbilical Vein Endothelial Cells (HUVECs) and how it influences the cell death. According to the results from real-time reverse transcription PCR, confocal laser scanning microscopy, and western blotting, a dose-dependent augmentation of CysLT2R protein expression in HUVECs was triggered by IL-18 for the first 2 h followed by down-regulation within the next 22 h after IL-18 administration. The flow cytometry showed that non-selective CysLT1R and CysLT2R antagonist BAY-u9773 could attenuate the early stage apoptosis mediated by IL-18 whereas CysLT1R antagonist Montelukast couldn''t. Also, pretreatment with BAY-u9773 suppressed calcium influx of HUVECs induced by IL-18 whereas Montelukast didn''t work. The observation that progression of cell death aggravated by IL-18 could be attenuated by BAY-u9773 may offer a chance to develop a novel way to treat arteriosclerosis. [Copyright &y& Elsevier]

Background: This study utilized a comprehensive nomogram to evaluate the prognosis of patients with COVID-19 pneumonia.Methods: COVID-19 pneumonia data was divided into training set (256 of 321, 80%), internal validation set (65 of 321, 20%) and independent external validation set (n = 188). After image processing, lesion segmentation, feature extraction and feature selection, radiomics signatures and clinical indicators were used to develop a radiomics model and a clinical model respectively. Combining radiomics signatures and clinical indicators, a radiomics nomogram was built. The performance of proposed models was evaluated by the receiver operating characteristic curve (AUC). Calibration curves and decision curve analysis were used to assess the performance of the radiomics nomogram.Results: Two clinical indicators that were age and chronic lung disease or asthma and 21 radiomics features were selected to build the radiomics nomogram. The radiomics nomogram yielded an Area Under The Curve1 (AUC) of 0.88 and accuracy of 0.80 in the training set, an AUC of 0.85 and accuracy of 0.77 in internal testing validation set and an AUC of 0.84 and accuracy of 0.75 in independent external validation set. The performance of radiomics nomogram was better than clinical model (AUC = 0.77, p < 0.001) and radiomics model (AUC = 0.72, p = 0.025) in independent external validation set.Conclusions: The radiomics nomogram may be used to assess the deterioration of COVID-19 pneumonia. [ABSTRACT FROM AUTHOR]

We present an overview of multiscale computations for free surface flows based on the front tracking method. Our approach combines theory, numerical algorithm development, simulation-based scientific studies, and the analysis of experimental data. [Copyright &y& Elsevier]

Bone marrow mesenchymal stem cell (BMSC) transplantation is a promising treatment for ischemic stroke that carries a severe mortality and disability burden amongst the adult population globally. Thus far, BMSC transplantation has been insufficient for ameliorating neurological deficits resulting from cerebral ischemia. This shortcoming may be an outcome due to poor homing and viability of grafted cells in ischemic brain that limit the potential therapeutic benefits of BMSC transplantation. Insulin-like growth factor-1 (IGF-1), a potent anti-apoptotic agent, exerts neuroprotective effects in ischemic stroke as well as rescuing neuronal death in vitro. We hypothesized that IGF-1 could also protect BMSCs from apoptotic death, and examined whether the combination of BMSCs with IGF-1 can enhance functional recovery outcomes in mice following cerebral ischemia. Intranasal administration of BMSCs with IGF-1 was applied in a mouse focal ischemic stroke model. Our in vitro results indicated that BMSCs treated with IGF-1 exhibited less apoptotic death induced by oxygen-glucose deprivation (OGD), and an improved migratory capacity. At 14 days after ischemic insult, the combination of BMSCs with IGF-1 resulted in a larger number of NeuN/BrdU and Glut-1/BrdU co-labeled cells in the areas contiguous to the ischemic core than IGF-1 or BMSC treatment alone. Western blot assays demonstrated that the protein levels of BDNF, VEGF and Ang-1 were significantly upregulated in the peri-infarct region in the combination treatment group compared with single IGF- 1 or BMSC treatment. Co-administration of BMSCs and IGF-1 markedly increases local cerebral blood flow and promoted better functional behavior outcomes. These data suggest that intranasal delivery of BMSCs in conjunction with IGF-1 strengthened functional recovery following ischemia via increasing neurogenesis and angiogenesis, providing a novel optimized strategy for improving the therapeutic efficacy of BMSC transplantation for ischemia. • Intranasally delivered bone marrow mesenchymal stem cells (BMSCs) after ischemic stroke • Co-applied insulin-like growth factor-1 (IGF-1) protected BMSCs from apoptosis and promoted cell migration • Combination of BMSCs with IGF-1 enhanced functional outcomes after stroke. • Upregulated BDNF, VEGF and Ang-1 in the peri-infarct region may mediate the beneficial effects. • Intranasal BMSCs and IGF-1 strengthened functional recovery after ischemia via increasing neurogenesis and angiogenesis. [ABSTRACT FROM AUTHOR]

Rationale Many recent studies suggest that the kallikrein-kinin system play a protective role in the impairment of vascular smooth muscle cells and vascular endothelial cell. Aims The study aims to determine whether tissue kallikrein is efficacy for preventing the long-term in-stent restenosis after stenting of symptomatic atherosclerotic stenosis of the middle cerebral artery M1 segment. Design This is a Phase II, randomized, single-blinded, controlled trial. In line with SAMMPRIS stenting indications, patients ( n = 90) with the symptomatic the middle cerebral artery M1 segment stenosis ≥70% and successfully treated with stent will be enrolled. Eligible patients will be randomized using computer generated numbers, and allocated to receive tissue kallikrein treatment or not. Patients in tissue kallikrein treatment group will be prescribed with intravenous infusion of tissue kallikrein (0·15 PNAU/d, dissolved in 100 ml saline) for 7 days after stenting and then oral administration of pancreatic kallikrein enteric-coated tablet (240 U, 3/d) to the end of study. As the foundation treatment, all the enrolled patients will receive aspirin (100 mg/d), clopidogrel (75 mg/d), and atorvastatin (20 mg/d) for the first 6 months and continue with the combination of aspirin and atorvastatin at the previous dosage. Study outcomes Patients will be evaluated at 1, 6 and 12 months after stenting. The primary outcomes are the in-stent restenosis rate, new stroke or aggravation of the previous ischemic stroke ipsilateral to the severe stenotic artery. Secondary outcomes include stroke of other artery territories, myocardial infarction and vascular death. Modification of stroke knowledge, exercise and diet habit, smoking cessation and available laboratory data will also be recorded. Conclusion As our pilot study, tissue kallikrein would be expected to prevent the long-term in-stent restenosis after stenting of the symptomatic middle cerebral artery dramatically. [ABSTRACT FROM AUTHOR]

The biscuits-like Co-VN@C composite was prepared from Co 3 V 2 O 8 nanosheets by hydrothermal method and ammonia nitridation. The Co nanoparticles were uniformly embedded in the VN nanosheets. This structure feature more exposed active sites and massive porosities, which facilitates the charge transfer and enhances the electrochemical performance. After different rates test, when the current density jumped back to 0.1 A g−1, the capacity of Co-VN@C electrode could go back to 588.0 mAh g−1. This work suggests that this novel structure of Co-VN@C electrode may have a significant influence on the energy storage and water oxidation filed, and may provide a way to design unique electrodes for diverse electrochemical energy storage and conversion devices. • The Co nanoparticles are uniformly in situ segregated on VN nanosheets. • The Co-VN@C electrode shows good rate and cycling performance. • The Co-VN@C also shows good electrochemical catalysis properties for OER. Biscuit-like Co-VN@C synthesized by a hydrothermal process and nitriding has outstanding electrochemical properties as anode materials in lithium-ion batteries (LIBs) and catalysts in the oxygen evolution reaction (OER). The metallic Co nanoparticles with abundant exposed active sites are segregated uniformly on VN nanosheets in situ so that they adhere strongly to the VN substrate leading to accelerated charge transfer and enhanced stability. The carbon shell of the composite acts as a buffer layer to alleviate the volume expansion and the battery shows a stable capacity of 335.5 mAh g−1 after500 cycles at 0.5 A g−1. After testing at different rates, the current density reverts back to 0.1 A g−1 and the capacity of the Co-VN@C electrode returns to 588.0 mAh g−1. Besides, Co-VN@C has excellent electrochemical catalytic activity in the oxygen evolution reaction. This work sheds light on the long cycle stability and high rate capacity electrode materials for future development of LIBs and the strategy provides insights into the design of high-performance electrode materials for electrochemical catalysis. [ABSTRACT FROM AUTHOR]

A 49-year-old female presented with recurrent intolerable right retro-orbital pain, ptosis and diplopia for 4 months. Neurological evaluation revealed right oculomotor nerve and abducent nerve injuries. Neuroimaging found enlarged right cavernous sinus, right intracavernous carotid dissection aneurysm and a stenosis proximal to it. Tolosa-Hunt syndrome (THS) was suggested and treated with steroid. The clinical symptoms were alleviated after the treatment. After 3 months of follow-up cerebral angiography showed the lesions of the right intracavernous carotid stenosis and the dissection almost disappeared. Therefore, we proposed that the dissection and the stenosis are directly induced by the inflammation of THS. [ABSTRACT FROM AUTHOR]

• rs2073617 or rs3134069 are associated with risk of poor outcome of LAA stroke. • The rs2073618 is not associated with risk of short-term poor outcome of LAA stroke. Osteoprotegerin is involved in the progression of atherosclerosis. This study aimed to determine whether TNFRSF11B polymorphisms are associated with prognosis of large artery atherosclerosis (LAA) stroke. Three TNFRSF11B polymorphisms (rs2073617, rs2073618 and rs3134069) were genotyped in 1010 patients with LAA stroke. Short-term outcome was evaluated using the modified Rankin Scale score at 3-month after stroke onset. Long-term outcome was assessed using the stroke recurrence. We found that rs2073617G was associated with an increased risk of poor outcome of LAA stroke (additive model: odds ratio (OR) = 1.35, 95% confidence interval (CI) = 1.06–1.73). This association was also observed in rs3134069C (additive model: OR = 1.53, 95% CI = 1.10–2.12). Furthermore, when we combined these two polymorphisms according to the numbers of risk alleles (rs2073617G and rs3134069C), we found that the patients with 3–4 risk alleles were statistically significantly associated with an increased risk of poor outcome of LAA stroke (OR = 1.90, 95% CI = 1.10–3.28) compared with 0–2 risk alleles, and this increased risk was more evident among those with hypertension (OR = 2.02, 95% CI = 1.04–3.91), those without diabetes (OR = 2.02, 95% CI = 1.02–4.01) and those with smoking (OR = 2.43, 95% CI = 1.09–5.42). In silico analysis showed that rs2073617 and rs3134069 are located in various histone modification marked regions, DNase I hypersensitive sites and can change the binding of regulatory motifs. Moreover, rs2073617 is also located in the binding site of transcription factors. Our findings suggested that TNFRSF11B polymorphisms may be associated with an increased risk of short-term poor outcome of LAA stroke. [ABSTRACT FROM AUTHOR]

Seasonal influenza remains epidemic globally with a substantial health burden. Understanding the transmission patterns and epidemic features of influenza may facilitate the improvement of preventive and control measures. This study aims to assess the epidemic features of influenza among different climate zones and identify high-risk zones across Gansu province, China. We collected weekly influenza cases at county-level between 1st January 2012 and 31st December 2016, as well as climate zones classification shapefile data from Köppen-Geiger climate map. We compared the epidemic features (Frequency index (α), Duration index (β) and Intensity index (γ)) of influenza among different climate zones. Spatial cluster analysis was used to examine the high-risk areas of transmission of influenza. The distribution of cases existed significant differences among eight climate zones (F-test: 267.02, p < 0.05). The highest mean weekly incidence rate (per 100,000 population) was 0.59 in snow climate with dry winter and warm summer (Dwb). The primary (relative risk (RR): 3.61, p < 0.001) and secondary (RR: 2.45, p < 0.001) clusters were located in Dwb. The highest values of α , β and γ were 1.00, 261 and 154.38 in Dwb. The hot spots (high-high clusters) of the epidemic indices were detected in Dwb. This study found the variability of epidemic features of influenza among eight climate zones. We highlight that Dwb was the high-risk zone where influenza clustered with the highest incidence rate and epidemic temporal indices. This provide further insight into potential improvement of preventive measures by climate zones to minimize the impact of epidemics. • There is a variability of epidemic features of influenza among climate zones. • Both primary and secondary spatial cluster of infection was observed in Dwb. • Influenza occurs more frequently with long-lasting and rapid spread in Dwb. • Hot spot areas (high-high cluster) of temporal risk mainly located in Dwb areas. [ABSTRACT FROM AUTHOR]

Nonlinear Optical Materials: ZnS Nanospheres for Optical Modulator in an Erbium-Doped Fiber Laser (Ann. Zinc sulfide (ZnS) is a semiconductor material with wide direct band gap, which has some special applications by changing the morphology, size, and crystal structure of semiconductor materials. In article number 1900454, Xiaohui Li, Xinfeng Liu, and co-workers use ZnS nanospheres to realize optical modulators in an Er-doped fiber laser. [Extracted from the article]

Manipulating the bandgap structure and carrier distribution of multilayer transition metal dichalcogenides (TMDs) is crucial for improving their fluorescence efficiency and extending their optoelectronic applications. Herein, the evolution of the conduction band minimum of multilayer WSe2 as a function of the temperature and thickness is experimentally demonstrated and an ≈70‐fold fluorescence enhancement of the K–K direct emission is observed at 560 K in multilayer WSe2 flakes (≈170 nm) by heat engineering. This abnormal enhancement is attributed to thermally driven carrier redistribution achieved via intervalley transfer, which is confirmed by the theoretical calculations and temperature‐dependent time‐resolved photoluminescence. In addition, a threshold temperature of the intervalley transfer is proposed to describe the on‐state of the carrier redistribution model. The corresponding threshold temperature is determined to be ≈580 K, which is consistent with the temperature at which the maximum photoluminescence enhancement is observed. The study provides a useful strategy to optimize the optical and electric performances of multilayer WSe2 and other TMDs materials. [ABSTRACT FROM AUTHOR]

• Compensatory collateral pathway patency through the AcomA. • Elevation of cerebral blood flow and perfusion due to AcomA flow. • Alleviation of ischemic injury facilitated by AcomA flow. • Quantitative analysis of collaterals in recurrent stroke model. Previous studies have estimated that the risk of recurrent stroke was nearly 20% shortly after a transient ischemic attack (TIA) or minor stroke. A missing or hypoplastic (<0.5 mm) anterior communicating artery can have deleterious effects on the brain. Our study aimed to investigate the effect of anterior communicating artery flow on neurovascular injury and neurobehavioral outcomes in mice with recurrent stroke and to identify its underlying mechanisms. A recurrent stroke model was established by an initial cortical infarction followed by a corticostriatal infarction 3 days later. The vascular structure was visualized using synchrotron radiation angiography & magnetic resonance angiography in vivo and transparent endovascular perfusion imaging in vitro. Microvessel perfusion was assessed via fluorescein isothiocyanate perfusion. The infarct volume was measured by magnetic resonance imaging. The finding that anterior communicating artery flow facilitates pial artery patency in the ipsilateral hemisphere in mice with recurrent stroke suggests that compensatory collateral patency contributes to increased regional cerebral blood flow, enhanced microcirculatory perfusion, improved neurological function and reduced infarct volume. The results of this study demonstrate that anterior communicating artery flow alleviates recurrent stroke-induced neurovascular injury and improves neurobehavioral outcomes by promoting the establishment of collateral circulation. [ABSTRACT FROM AUTHOR]

As an important 2D layered metal dichalcogenide, germanium diselenide (GeSe2) with a direct wide bandgap is attracting increasing attention for its potential applications in ultraviolet (UV) detection. However, only few‐layer GeSe2 has been reported to date. Here, a joint theoretical–experimental study on the optical and electronic properties of monolayer GeSe2 is presented, and monolayer GeSe2 is shown to have a direct wide bandgap of 2.96 eV. Consequently, monolayer GeSe2 does not respond to a major fraction of the visible spectrum. Notably, the photofield effect transistors based on the GeSe2 monolayer show p‐type behavior, high responsivity, superior detectivity, and a fast response time, competitive with state‐of‐the‐art UV detectors. In addition to the excellent photoresponse properties, 2D GeSe2 crystals also exhibit perpendicular optical reversal of the linear dichroism and polarized photodetection under wavelength modulation. Theoretical calculations of the band structure are used to shed light on these experimental results. The findings suggest that 2D GeSe2 is a promising candidate for highly selective polarization‐sensitive UV detection. [ABSTRACT FROM AUTHOR]

Continuous‐wave (CW) operated lasers are regarded as a stepping stone to the development of electrically driven lasers and crucial for practical application in high‐density integrated optoelectronic devices. Recently, metallic halide perovskites are demonstrated as excellent gain materials for CW lasers owing to their large optical absorption coefficient, low defect density, long diffusion length, and suppressed Auger recombination rate. Here, the latest research advances on CW pumped perovskite lasers are reviewed. First, the recent research advances on CW lasing in perovskite thin film are highlighted. Then, CW lasing in CsPbBr3 perovskite nanowires is briefly introduced. The comparison of lasing thresholds in CW perovskite lasers is made and discussed. Finally, the importance of such perovskite CW lasers is emphasized, while a perspective on the potential opportunities and remaining challenges of perovskite‐based CW lasers is proposed. [ABSTRACT FROM AUTHOR]

Background: Functions of astrocytes in the rehabilitation after ischemic stroke, especially their impacts on inflammatory processes, remain controversial. This study uncovered two phenotypes of astrocytes, of which one was helpful, and the other harmful to anoxic neurons after brain ischemia.Methods: We tested the levels of inflammatory factors including TNF-a, IL-6, IL-10, iNOS, IL-1beta, and CXCL10 in primary astrocytes at 0 h, 6 h, 12 h, 24 h, and 48 h after OGD, grouped the hypoxia astrocytes into iNOS-positive (iNOS(+)) and iNOS-negative (iNOS(-)) by magnetic bead sorting, and then co-cultured the two groups of cells with OGD-treated neurons for 24 h. We further verified the polarization of astrocytes in vivo by detecting the co-localization of iNOS, GFAP, and Iba-1 on MCAO brain sections. Lentivirus overexpressing LCN2 and LCN2 knockout mice (#024630. JAX, USA) were used to explore the role of LCN2 in the functional polarization of astrocytes. 7.0-T MRI scanning and the modified Neurological Severity Score (mNSS) were used to evaluate the neurological outcomes of the mice.Results: After oxygen-glucose deprivation (OGD), iNOS mRNA expression increased to the peak at 6 h in primary astrocytes, but keep baseline expression in LCN2-knockout astrocytes. In mice with transient middle cerebral artery occlusion (tMCAO), LCN2 was proved necessary for astrocyte classical activation. In LCN2 knockout mice with MCAO, no classically activated astrocytes were detected, and smaller infarct volumes and better neurological functions were observed.Conclusions: The results indicated a novel pattern of astrocyte activation after ischemic stroke and lipocalin-2 (LCN2) plays a key role in polarizing and activating astrocytes. [ABSTRACT FROM AUTHOR]

Background: The topographic location of acute pontine infarction is associated with clinical syndromes and prognosis. Previous studies focused on isolated pontine infarction, but the topographic location of unisolated pontine infarction has remained unclear.Methods: This was a prospective, multicenter, longitudinal registry study. Patients with acute pontine infarction confirmed by magnetic resonance imaging (MRI) were enrolled. Based on the territory of the pontine artery, the topographic location was divided into anteromedial, anterolateral, tegmental, bilateral and unilateral multiple infarctions.Results: From May 1, 2003, to Oct 31, 2017, 1003 patients were enrolled, and 330 had unisolated pontine infarction. For isolated pontine infarction, 44.9, 19.8, 16.0, 13.1 and 6.2% of patients had anteromedial, anterolateral, tegmental, bilateral and unilateral multiple pontine infarctions, respectively. For unisolated pontine infarction, 30.3, 19.7, 24.5, 15.2 and 10.3% of patients had anteromedial, anterolateral, tegmental, bilateral and unilateral multiple pontine infarctions, respectively.Conclusion: In this large series study, our data revealed fewer anteromedial infarctions and more tegmental and unilateral multiple infarctions in patients with unisolated pontine infarction than in patients with isolated pontine infarction. [ABSTRACT FROM AUTHOR]

2D layered halide perovskites have attracted significant attention. Apart from the linear optical properties, it is also intriguing to explore the nonlinear optics of 2D layered halide perovskites and their heterostructures. Previous nonlinear optical (NLO) studies of 2D perovskites primarily focus on the thin films or microplates. Herein, the NLO properties of (n‐C4H9NH3)2PbI4/(n‐C4H9NH3)2(CH3NH3)Pb2I7 heterostructures with centimeter size are systematically studied. The NLO properties can be continuously tuned by changing the thickness. A giant two‐photon absorption (2PA) coefficient up to 44 cm MW−1 is obtained for the heterostructures with a total thickness of 20 µm based on the nonlinear transmittance measurement. Additionally, strong multiphoton‐induced photoluminescence is observed in the heterostructures. It is proposed that the giant 2PA coefficient might arise from the small thickness (≈1 µm) of (n‐C4H9NH3)2(CH3NH3)Pb2I7 layer and possibly the nonradiative energy transfer between the different constituting layers within the heterostructures through an antenna‐like effect. Finally, benefiting from the giant 2PA coefficient, direct detection of 980 nm light is demonstrated with a responsivity of 10−7 A W−1 in the heterostructures. The findings suggest the promising applications of 2D perovskite heterostructures in the infrared photodetection and some other nonlinear absorption related optoelectronic devices. [ABSTRACT FROM AUTHOR]

Background: Patients with vertebrobasilar dolichoectasia usually have persistent hemodynamic abnormalities, and therefore, may bear an increased risk of stroke. This study aimed to identify risk factors for stroke recurrence in patients with vertebrobasilar dolichoectasia.Methods: Patients with acute ischemic stroke were screened and evaluated for eligibility. Enrolled patients were followed via scheduled clinical visits or telephone interviews. Ischemic stroke recurrence was proposed with clinical symptoms and confirmed with cranial Magnetic Resonance Imaging or Computerized Tomography scans. Baseline characteristics and vascular geometry were compared between patients with and without stroke recurrence. Significant parameters were introduced into COX proportional hazard model to detect possible predictors of stroke recurrence.Results: A total of 115 stroke patients with vertebrobasilar dolichoectasia were enrolled, of which 22 (19.1%) had recurrence during 22 ± 6 months follow-up. Basilar artery diameter ≥ 5.3 mm (HR = 4.744; 95% CI, 1.718-13.097; P = 0.003), diffuse intracranial dolichoectasia (HR = 3.603; 95% CI, 1.367-9.496; P = 0.010) and ischemic heart disease history (HR = 4.095; 95% CI, 1.221-13.740; P = 0.022) had increased risk of recurrence.Conclusions: Stroke patients with vertebrobasilar dolichoectasia may have a high risk of recurrence. Larger basilar artery diameter or diffuse intracranial dolichoectasia may increase the risk of recurrence. [ABSTRACT FROM AUTHOR]

Biexcitons are a manifestation of many-body excitonic interactions, which are crucial for quantum information and computation in the construction of coherent combinations of quantum states. However, due to their small binding energy and low transition efficiency, most biexcitons in conventional semiconductors exist either at cryogenic temperatures or under femto-second pulse laser excitation. Herein, we demonstrated strong biexciton emissions from CsPbBr3 nanoplatelets with continuous-wave excitation at room temperature by coupling them with a plasmonic nanogap. The exciton occupancy required to generate biexciton was reduced ~106 times in the Ag nanowire–Ag film nanogaps. The extremely large enhancement of biexciton emissions was driven by nonlinear Fano resonance between biexcitons and surface plasmon cavity modes. These results provide new pathways to develop high efficiency non-blinking single photon sources of biexciton (with spectral filter for biexciton), entangled light sources, and lasers based on biexciton states. The quasiparticle the biexciton is expected to be an important component in the construction and application of quantum states in quantum information computing but is typically not stable under ambient conditions. Here, the authors use nanoplasmonics to achieve the generation of biexcitons at room temperature in perovskite nanoplatelets. [ABSTRACT FROM AUTHOR]

High‐energy C exciton in 2D transition metal dichalcogenides with strong photon absorption can be utilized prospectively in light‐harvesting and opto‐electric devices. Here, a detailed study on C exciton dynamics in monolayer MoS2 is presented by femtosecond transient absorption (TA) spectroscopy. In the experiment, the C exciton with unique parallel band structure exhibits a slow process within tens of picoseconds (≈10–50 ps) as well as a fast process within several picoseconds (≈1–6 ps) instead of previous reported ultrafast cooling (<500 fs) process. From TA spectroscopy, the experimental results confirmed that the relatively slow cooling of C exciton is mainly limited by the rates of intervalley transfer rather than Pauli blocking effect from band‐edge excitons. The timescale of intervalley transfer is longer than that of intraband relaxation of C exciton, therefore, leading to the slow cooling of C exciton. Moreover, intervalley transfer time are estimated with two processes of 5.1 ± 0.6 ps and 69.5 ± 8 ps when the pump fluence is ≈127 µJ cm−2. This work provides further understanding of the ultrafast dynamics of C exciton in monolayer MoS2 and opens new opportunities for opto‐electric related applications. Developing an insight into C exciton dynamics is important to effectively collect these high‐energy hot carriers in two‐dimensional transition metal dichalcogenides. Herein, the C exciton exhibits a slow cooling instead of a previous reported sub‐picosecond timescale. The experimental results based on transient absorption measurements confirm that the slow cooling of C exciton is mainly caused by intervalley transfer. [ABSTRACT FROM AUTHOR]

Poly(3‐hexylthiophene) (P3HT)‐based organic solar cells (OSCs) have attracted much attention due to their advantages of low‐cost production and matured roll‐to‐roll manufacture. However, the efficiency of P3HT‐based OSCs lag much behind the non‐P3HT ones due to their negligible absorption of long wavelengths of light over 650 nm, high‐lying highest occupied molecular orbitals (HOMO), and difficulty of controlling morphology. In this study, the alkyl chains of the nonfullerene acceptors are replaced with alkoxy chains to achieve synergistic enhancement of all three parameters ( short circuit current density (JSC), open circuit voltage (VOC), and fill factor (FF)) and thus significant increase of power conversion efficiency for P3HT‐based OSCs. As a result, the OSCs exhibit a maxima efficiency of 6.6%. The P3HT‐based systems are systematically studied with optical spectroscopy, photoluminescence, cyclic voltametry, space charge limit current, grazing incident wide‐angle X‐ray scattering, transient absorption spectroscopy, transmission electron microscope, and atomic force microscopy to probe the mechanism, which reveal that introducing alkoxy chains simultaneously increases the energy levels of the HOMO and the lowest unoccupied molecular orbitals, enhances the light absorption, improves the rigidity of the backbone and charge transport mobility, and tunes the molecular orientation and film morphology, thus improving the photovoltaic performance. This contribution provides an important guidance in the design of novel nonfullerene acceptors for high‐performance P3HT‐based OSCs. Replacement of alkyl chains with alkoxyl chains of the backbone of nonfullerene acceptors successfully increases the energy levels, enhances the light absorption, and improves charge transport mobility, which simultaneously enhances three parameters (short circuit current density (JSC), open circuit voltage (VOC), and fill factor (FF)), resulting in a highest efficiency for poly(3‐hexylthiophene) (P3HT)‐based organic solar cells (OSCs) (6.6%). [ABSTRACT FROM AUTHOR]

Plasmonic nanolaser holds great potential in breaking down the diffraction limit of conventional optics to the deep sub‐wavelength regime and in ultrafast lasing dynamics. However, plasmonic laser devices are constrained in practical applications due to their high cost and high thresholds. All‐inorganic cesium lead halide perovskites are promising solutions for their excellent optical gain properties and high emission efficiency. In this work, high‐quality single‐crystalline CsPbBr3 perovskite nanowires (NWs) are synthesized by chemical vapor deposition method. The plasmonic lasing is achieved from the CsPbBr3 nanowire based plasmonic devices with lasing threshold down to ≈6.5 µJ cm−2 at room temperature. The highly polarized emission parallel to nanowire axis and polarization‐sensitive pump response confirm the plasmonic characteristic in these devices. Furthermore, time‐resolved photoluminescence study suggests that the radiative recombination lifetime of CsPbBr3 NW is shortened by a factor of ≈6.14 due to Purcell effect. The lasing threshold of plasmonic device increases along with the nanowire length, indicating greater potential in small size and integration in plasmonic device than its photonic counterparts. The results not only provide a solution to fabricate low‐cost nanowire based plasmonic lasers, but also advocate the prospect of all‐inorganic perovskite nanowires as promising candidates in plasmonic‐based devices. Plasmonic nanolaser holds great potential in breaking down the diffraction limit of conventional optics to deep sub‐wavelength regime. Herein, all‐inorganic CsPbBr3 nanowire based plasmonic lasers are demonstrated at room tempearutre with threshold ≈6.5 µJ cm−2. The lasing threshold of plasmonic device increases along with the nanowire length, indicating greater potential in plasmonic integration device than its photonic couterparts. [ABSTRACT FROM AUTHOR]

Efficient ternary polymer solar cells (PSCs) are prepared with poly‐[4,8‐bis(5‐(2‐ethylhexyl)thiophen‐2‐yl)benzo[1,2‐b:4,5‐b′] dithiophene‐co‐3fluorothieno[3,4‐b]thiophene‐2‐carboxylate] (PTB7‐Th):COi8DFIC as host system and medium bandgap material BDTThIT‐4F as the third component. The power conversion efficiency of PSCs can be increased from 11.47% to 13.08% by incorporating 20 wt% BDTThIT‐4F in acceptors, along with the simultaneously improved three key photovoltaic parameters. The absorption edge of ternary blend films can be tilted up in long wavelength range by incorporating appropriate BDTThIT‐4F, although the bandgap of BDTThIT‐4F is wider than that of COi8DFIC, leading to the extended external quantum efficiency spectra of ternary PSCs. The tilted up absorption edge of blend films should be attributed to the variation of COi8DFIC molecular arrangement, which can be well demonstrated from the transient and steady absorption spectra of blend films with different donors and acceptors. A new ground state bleach signal can be clearly observed in transient absorption spectra of the optimized ternary blend films, which may be due to the varied COi8DFIC molecular energy levels by incorporating BDTThIT‐4F. Meanwhile, the lifetimes on excited states are increased in the ternary blend films, which is beneficial to exciton dissociation for improving the performance of ternary PSCs. Efficient ternary non‐fullerene polymer solar cells (PSCs) are fabricated with poly‐[4,8‐bis(5‐(2‐ethylhexyl)thiophen‐2‐yl)benzo[1,2‐b:4,5‐b′] dithiophene‐co‐3‐fluorothieno[3,4‐b]thiophene‐2‐carboxylate] (PTB7‐Th):COi8DFIC:BDTThIT‐4F as active layers. The power conversion efficiency is increased from 11.47% to 13.08% by incorporating 20 wt% BDTThIT‐4F in acceptors, which is attributed to the tilted up absorption edge and the optimized phase separation of ternary active layers. [ABSTRACT FROM AUTHOR]

Objective: New vessels formation (NVF) along the steno‐occlusive middle cerebral artery (MCA) is often observed in digital subtraction angiography (DSA) imaging. In the study, we aim to explore the clinical relevance of NVF in young ischemic stroke patients with isolated middle cerebral artery (MCA) stenosis. Methods: We retrospectively reviewed the digital subtraction angiography (DSA) images of 93 young ischemic stroke patients (age ≤ 45 years old) in our center from January 2006 to June 2016. All the patients were diagnosed with isolated steno‐occlusive middle cerebral artery (MCA) disease.NVF was defined as new vessels formation along the stenotic MCA on anteroposterior DSA projection. The association between NVF and functional outcome was analyzed. Results: The prevalence of NVF was 0 in moderate stenosis, 15.8% in severe stenosis, and 53.7% in MCA occlusions. The presence of NVF had a strong correlation with the severity of MCA stenosis (r = 0.467, p < 0.001). Compared to patients without NVF, patients with NVF were more likely to suffer an unfavorable functional outcome (6.2% vs. 21.4%, p = 0.061) at 3 months. Univariate logistic regression analysis showed that NVF was associated with unfavorable outcome [Odds Ratio (OR) = 4.159, 95% confidence intervals (CI) = (1.072, 16.137), p = 0.039]. Conclusions: This study demonstrated that NVF were associated with poor clinical outcome in young ischemic stroke patients who were diagnosed with isolated steno‐occlusive MCA. New vessels formation was significantly correlated with the severity of MCA stenosis in young ischemic stroke patients with isolated MCA steno‐occlusive disease. In terms of stroke outcome, NVF predicts unfavorable outcome at 3 months after symptom onset. [ABSTRACT FROM AUTHOR]

Objective Successful recanalization (SR) of the occluded artery does not always translate into a good outcome for patients with acute anterior circulation large-vessel occlusion stroke. This study aimed to develop a scale to predict poor outcome early despite SR after endovascular treatment (EVT) for candidates identified using current guidelines. Methods The eligible patients with SR were retrospectively enrolled between 2014 and 2016. Poor outcome was defined as modified Rankin Scale of 3 to 6 at 90 days. Multivariable logistic regression was used to derive a PooR outcomE of enDovascular treatment wIth suCcessful recanalizaTion (PREDICT) scale. The discrimination and calibration of the scale were assessed. Results A total of 332 patients were enrolled. The PREDICT scale consisted of 5 items (prior intravenous thrombolysis, collateral status, blood glucose, blood neutrophil-to-lymphocyte ratio, and baseline National Institutes of Health Stroke Scale score). The scale had good discrimination and calibration. The risk of poor outcome was stratified into very low (PREDICT scale score ≤5), low (6–8), moderate (9–11), and high (≥12). Compared with patients with a score of ≤5, patients with a score of ≥12 had an 18.33-fold (95% confidence interval [CI], 6.36–52.89) increased risk of poor outcome. Conclusions The PREDICT scale is a practical tool for early prediction of poor outcome despite SR after EVT in our patients and, if validated in other patient populations, may serve as a scale for identifying which patients are most, and least, likely to benefit from EVT. [ABSTRACT FROM AUTHOR]

Background: Epilepsy is a major complication of stroke. We aimed to establish whether there is an association between intravenous thrombolysis, intra-arterial thrombolysis and post stroke seizure (PSS) development. Improved understanding of the relationship between reperfusion therapies and seizure development may improve post-stroke monitoring and follow-up.Methods: This was a retrospective, multicentre cohort study conducted at the Royal Melbourne Hospital and Jingling Hospital Nanjing. We included patients with anterior circulation ischemic stroke admitted 2008-2015. Patients were divided into four treatment groups 1. IV-tPA only, 2. Intra-arterial therapies (IAT) only, 3. IAT + IV-tPA and 4. stroke unit care only (i.e. no IV-tPA or IAT). To assess the association between type of reperfusion treatment and seizure incidence we used multivariable logistic regression models adjusted for age, stroke severity, 3-month functional outcome and prognostic factors.Results: There were 1375 stroke unit care-only patients, of whom 28 (2%) developed PSS. There were 363 patients who received only IV-tPA, of whom 21 (5.8%) developed PSS. There were 93 patients who received IAT only, of whom 12 (12.9%) developed PSS and 112 that received both IV-tPA + IAT, of which 5 (4.5%) developed PSS. All reperfusion treatments were associated with seizure development compared to stroke unit care-only patients: IV-tPA only adjusted odds ratio (aOR) 3.7, 95%CI 1.8-7.4, p < 0.0001; IAT aOR 5.5, 95%CI 2.1-14.3, p < 0.0001, IAT + IV-tPA aOR 3.4, 95% CI 0.98-11.8, p = 0.05. These aORs did not differ significantly between treatment groups (IV-tPA + IAT versus IV-tPA p = 0.89, IV-tPA + IAT versus IAT, p = 0.44).Conclusions: Patients receiving thrombolytic or intra-arterial reperfusion therapies for acute ischemic stroke are at higher risk of epilepsy and may benefit from longer follow-up. No evidence for an additive or synergistic effect of treatment modality on seizure development was found. [ABSTRACT FROM AUTHOR]

Stroke is one of the leading causes of death and long-term disability worldwide. Mitochondrial DNA (mtDNA) is a potential contributor for the sex differences of ischemic stroke heritability. Although mtDNA haplogroups were associated with stroke onset, their impacts on stroke outcomes remain unclear. This study aimed to evaluate the impacts of mtDNA haplogroups on short-term outcomes of neurological functions in patients with ischemic stroke. A total of 303 patients were included, and their clinical data and mtDNA sequences were analyzed. Based on the changes between baseline and 14-day follow-up stroke severity, our results showed that haplogroup N9 was an independent protective factor against neurological worsening in acute ischemic stroke patients. These findings supported that mtDNA variants play a role in post-stroke neurological recovery, thus providing evidences for future pharmacological intervention in mitochondrial function. [ABSTRACT FROM AUTHOR]

Background: The NINDS-Canadian Stroke Network (NINDS-CSN) recommended a neuropsychological battery of three protocols to diagnose vascular cognitive impairment (VCI), however, due to culture and language differences, the battery cannot be directly used in China. Validation of the battery in mandarin Chinese is lacking. Our study investigated the reliability and validity of the adapted Chinese versions of the battery in stroke patients with high probability of VCI.Methods: Fifty mild stroke patients (median of National Institute of Health Stroke Scale [NIHSS] score, 2) and 50 stroke-free normal controls were recruited. All subjects' demographics, clinical history, and stroke severity were recorded. The NINDS-CSN neuropsychological protocols were adapted into the Chinese versions. External validity, defined as the ability of the protocol summary scores to differentiate stroke patients from controls, was determined using the area under the curve (AUC) of the receiver operating characteristics curve. We also evaluated internal consistency and intra-rater reliability.Results: Stroke patients performed significantly poorer than controls on all three protocols (F statistics between 24.9 and 31.4, P < 0.001). External validity evaluated by AUCs was 0.88 (95% confidence interval [CI], 0.81-0.95), 0.88 (95% CI, 0.81-0.94), and 0.86 (95% CI, 0.79-0.94) for the 60-min, 30-min and 5-min protocols, respectively. Cronbach's alpha of the cognitive tests was 0.87 for all subjects. Intra-rater reliability was acceptable with intraclass correlation coefficients 0.90, 0.83 and 0.75 for the 60-min, 30-min and 5-min protocols, respectively.Conclusions: The adapted Chinese versions of three NINDS-CSN neuropsychological protocols were valid and reliable for assessing VCI in Chinese patients with mild stroke. [ABSTRACT FROM AUTHOR]

The aim of this study is to assess related risk factors and predict early- and late-onset seizure after first-ever stroke. A total of 2474 consecutive patients with initial stroke in China from 1997 to 2007 were retrospectively investigated, in which, 24 clinical and radiological indexes were used for evaluation. Odds ratio (OR) and 95% confidence interval (CI) were calculated by logistic regression. A total of232 (11.1%) of patients developed seizures during a mean follow-up period of 18 months, with 123 experiencing early-onset and 109 late-onset seizure. The independent risk factors for early-onset seizure were large lesion (OR = 9.36), subarachnoid hemorrhage (OR = 5.28), initial hyponatremia (OR = 2.10), and cortical involvement (OR = 1.33). The independent risk factors for late-onset seizure were cortical involvement (OR = 11.84) and large lesion (OR = 1.87). These results demonstrated that the risk factors for early seizure after stroke are large lesion, subarachnoid hemorrhage, and cortical involvement. Surprisingly, hyponatremia also predicts seizure in stroke patients. Cortical involvement is a major risk factor for late-onset seizure after stroke. [ABSTRACT FROM AUTHOR]

Background: The effect of neurotrophic factors in enhancing stroke-induced neurogenesis in the adult subventricular zone (SVZ) is limited by their poor blood-brain barrier (BBB) permeability.Intranasal administration is a noninvasive and valid method for delivery of neuropeptides into the brain, to bypass the BBB. We investigated the effect of treatment with intranasal transforming growth factor-beta1 (TGF-beta1) on neurogenesis in the adult mouse SVZ following focal ischemia. The modified Neurological Severity Scores (NSS) test was used to evaluate neurological function, and infarct volumes were determined from hematoxylin-stained sections. Terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL) labeling was performed at 7 days after middle cerebral artery occlusion (MCAO). Immunohistochemistry was used to detect bromodeoxyuridine (BrdU) and neuron- or glia-specific markers for identifying neurogenesis in the SVZ at 7, 14, 21, 28 days after MCAO.Results: Intranasal treatment of TGF-beta1 shows significant improvement in neurological function and reduction of infarct volume compared with control animals. TGF-beta1 treated mice had significantly less TUNEL-positive cells in the ipsilateral striatum than that in control groups. The number of BrdU-incorporated cells in the SVZ and striatum was significantly increased in the TGF-beta1 treated group compared with control animals at each time point. In addition, numbers of BrdU- labeled cells coexpressed with the migrating neuroblast marker doublecortin (DCX) and the mature neuronal marker neuronal nuclei (NeuN) were significantly increased after intranasal delivery of TGF-beta1, while only a few BrdU labeled cells co-stained with glial fibrillary acidic protein (GFAP).Conclusion: Intranasal administration of TGF-beta1 reduces infarct volume, improves functional recovery and enhances neurogenesis in mice after stroke. Intranasal TGF-beta1 may have therapeutic potential for cerebrovascular disorders. [ABSTRACT FROM AUTHOR]