Background and PurposePurposezzInterest in gender differences in the effects of acute stroke is growing worldwide. However, gender differences in functional recovery after acute stroke in the Korean population have yet to be evaluated. The aim of this investigation was to compare long-term functional outcomes between male and female after acute stroke.MethodsPatients with acute stroke were enrolled prospectively between January 2005 and January 2009. Baseline characteristics, risk factors, stroke subtypes, time delay from onset to arrival at a hospital, active treatment, and stroke severity were compared between male and female. Differences in mortality and disability at discharge, and at 3 months and 1 year after stroke onset were also investigated. Functional disabilities were categorized into two groups: good outcome (score on modified Rankin scale ≤2) and poor outcome (score on modified Rankin scale >2).ResultsAmong 1,055 patients with acute stroke, 575 were male (aged 64.83±11.98 years, mean±SD) and 480 were female (aged 70.09±13.02 years). There were no gender differences in mortality at 3 months and 1 year after stroke. The frequency of poor outcomes was higher in female patients than in male patients at discharge (39.8% versus 30.9%, respectively; p=0.003), the 3 months follow-up (32.3% versus 20.8%, respectively; p<0.001), and the 1 year follow-up (31.1% versus 18.7%, respectively; p=0.001). After adjusting for multiple confounding factors including age and stroke severity, the female gender persisted as a predictor of poor functional outcome at 3 months and 1 year after stroke.ConclusionsFemale patients have greater difficulty than male patients in recovering from a disabled state after acute stroke. Future studies should investigate the causes of this gender difference.

Copper nanowire (Cu NW)-based flexible transparent conductive electrodes (FTCEs) have been investigated in detail for use in various applications such as flexible touch screens, organic photovoltaics and organic light-emitting diodes. In this study, hexadecylamine (HDA) adsorbed onto the surface of NWs is changed into polyvinylpyrrolidone (PVP) via a ligand exchange process; the high-molecular-weight PVP enables high dispersion stability. Intense pulsed light (IPL) irradiation is used to remove organic species present on the surface of the NWs and to form direct connections between the NWs rapidly without any atmospheric control. NWs are self-nanoembedded into a plastic substrate after IPL irradiation, which results in a smooth surface, strong NW/substrate adhesion, excellent mechanical flexibility and enhanced oxidation stability. Moreover, Cu NW FTCEs with high uniformities are successfully fabricated on a large area (150 mm × 200 mm) via successive IPL irradiation that is synchronized with the motion of the sample stage. This study demonstrates the possibility of roll-to-roll-based, large-scale production of low-cost, high-performance Cu NW-based FTCEs.

Background: Decreased glomerular filtration rate (GFR) can increase the risk of bleeding tendency and hemorrhagic stroke. However, the relationship between the levels of GFR and hemorrhagic transformation (HT) after acute ischemic stroke is largely unknown. The aim of this study was to assess whether GFR level is associated with HT in acute ischemic stroke. Methods: We reviewed 770 consecutive patients with acute ischemic stroke within 7 days from September 2007 to February 2012 in a prospective stroke registry database. We calculated the patient’s GFR using the Cockcroft-Gault equation, and divided them into 3 groups: ≥60, 30–59 and <30 ml/min/1.73 m². HTs were identified by follow-up computed tomography (CT) or magnetic resonance imaging, and were defined as (1) any degree of high density within the area of low attenuation of vascular territory on noncontrast brain CT, or (2) low-signal intensity area in gradient echo within high-signal intensity meaning acute infarct on diffusion-weighted imaging. Multivariable logistic regression analyses were used to estimate the risk of GFR for HT. Stratification analyses were done according to the presence of HT high risk factors: atrial fibrillation (AF), thrombolysis and large size infarction. Additional logistic regression model for symptomatic HTs was established with the same variables. Results: HTs were noted in 131 patients (17.0%) and symptomatic HTs in 63 patients (8.2%). In univariate analysis, HTs were more frequent in patients with AF (51.9 vs. 16.7%, p < 0.001) and large-size infarction (42.0 vs. 5.3%, p < 0.001). The risk of HT was associated with decreased GFR among 3 subgroups classified according to the value of estimated GFR: 49/394 (12.4%) in the GFR ≥60 group, 66/312 (21.2%) in the 30≤ GFR <59 group and 16/64 (25.0%) in the GFR <30 group (p = 0.002). We found a significant association between the GFR <30 group and HTs in acute ischemic stroke (OR 2.90; 95% CI 1.26–6.68, p = 0.012) after adjusting for other risk factors. Moreover, the incidence of HTs was higher in the subgroups without thrombolysis (OR 3.49; 95% CI 1.44–8.46) and without AF (OR 3.44; 95% CI 1.10–10.76). Decreased GFR also had a tendency of increasing symptomatic HTs (OR 2.39; 95% CI 0.72–7.94, p = 0.154). Conclusions: Low levels of GFR are associated with a high risk of HT after acute ischemic stroke. Further studies are needed to elucidate whether HT in the patients with renal insufficiency are related to a worse outcome after acute ischemic stroke.

in PSCs has been accomplished within a relatively short period of time, owing to OMHP's merits for low-cost, large-area, flexible photovoltaic applications; these merits include (i) the precursor chemicals, including organic ammonium halides and lead (tin) halides, for synthesizing the OMHP materials are cost-effective, and the OMHP layers can be readily prepared by simple wet-chemical approaches such as a spin coating or a slot-die coating process; (ii) the processing temperatures are relatively low, below 150 °C, for the formation of well-crystalized OMHP layers, in contrast to other thin-film-based solar cells; (iii) both the high absorption coefficients [6] and high carrier mobilities [7] suggest promising possibilities for highperformance photoactive materials. The PCE certified by National Renewable Energy Laboratory (NREL) reached 22.1% in 2016, [8] which is either comparable to or outperforms the PCEs of other next-generation thin-film solar cells, including CIGS(Se) (22.3%), CZTS/Se (12.6%), CdTe (22.1%), and organic photovoltaics (OPVs, 11.5%).Apart from the race to achieve higher PCE, other important research has been directed toward the development of lead-free OMHP layers, [9] large-area device fabrication, [10,11] a methodology of achieving long-term stability against moisture and irradiation, [12,13] and a way of recycling constituent cell materials. [14] Another fascinating research topic concerns the electrodes for PSCs. To date, vacuum-deposited transparent conductive oxides (TCOs), such as indium tin oxide (ITO) and fluorinated tin oxide (FTO), have been used widely as a large-area window electrode through which light passes. However, TCOs have received criticism in terms of their fabrication cost, brittleness, and the scarcity of raw materials (especially, the indium in ITO). [15] Opaque noble metal electrodes (Au, Ag), which are usually used as a back contact, are also fabricated with a costly vacuum-assisted deposition process. From the viewpoint of cost-effectiveness, both transparent and opaque conventional electrodes apparently represent predominant impediments to the high-throughput fabrication of PSCs, giving rise to a significant demand to replace these conventional electrodes with alternatives.To date, a variety of alternative electrodes have been reported in the literature.

The concept of using core Cu nanowires (CuNWs) that are conformally encapsulated by a reducible fugitive material for transparent conducting electrodes (TCEs) with high oxidation stability is presented. By the chemical reaction of an acid with surface oxide and hydroxide, a uniform surface shell layer is readily obtained on each CuNW upon adding lactic acid to the CuNW dispersion. The Cu lactate shell prevents the core CuNW from oxidizing during storage and film formation, enabling the core Cu nanowires to maintain their characteristic optoelectronic properties. Through simple thermal annealing under a nitrogen atmosphere, the Cu lactate shell is easily decomposed to expose the underlying pure Cu, providing an effective way to produce a pure‐CuNW‐network TCE with a sheet resistance of 19.8 Ω sq−1 and an optical transmittance of 85.5% at 550 nm. The application of the CuNW‐based TCE to the transparent top electrode in organometallic halide perovskite solar cells is further demonstrated for the first time, yielding a power‐conversion efficiency 9.88% as compared to that of 13.39% for conventional perovskite solar cells with an indium–tin‐oxide electrode. This study proposes the high feasibility of these CuNWs as a vacuum‐free and noble‐metal‐free transparent‐window electrode in perovskite solar cells.

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Photocatalytic water splitting is the most environmentally friendly method to generate energy. Despite intense research in this area, rapid charge-carrier recombination and limited light absorption of semiconductor-based photocatalysts remain key challenges. Herein, protonated g-C 3 N 4 /Ti 3 C 2 T x MXene hollow spheres, fabricated by electrostatic layer-by layer assembly and a sacrificial template, were used for effective photocatalytic hydrogen (H 2 ) evolution. The constructed three-dimensional (3D) hollow spheres exhibited enhanced light absorption, a two-dimensional (2D) heterostructure to shorten the electron migration distance, a Schottky junction to facilitate separation and transfer of charge carriers, and high specific surface area for efficient H 2 adsorption. The optimal formulation had an H 2 production rate of 982.8 μmol g −1 h −1 , which is more than 3.5-fold higher than the H 2 production rate of pure protonated g-C 3 N 4 and 1.22-fold higher than the H 2 production rate of protonated g-C 3 N 4 /Ti 3 C 2 T x , which lacks the hollow structure. This unique 3D heterojunction structure made from 2D materials improved photocatalytic H 2 production performance and can be readily extended to other reactions. KEYWORDS: Ti 3 C 2 T x MXene, g-C 3 N 4 , photocatalytic water splitting, hydrogen evolution reaction, 3D architecture

The effects of La2O3 interface modification of mesoporous TiO2 on the photovoltaic performance of perovskite solar cells are investigated.