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Oscillating body wave energy converter (OBWEC) is an essential way to exploit wave energy. Existing OBWECs with a single degree of freedom (DOF) suffer from a low energy conversion ratio. Although this power generation limit of OBWECs can be alleviated by increasing DOF, for the multi-DOF OBWEC, specific structure design guidelines, accurate energy conversion modeling and economic cost-related performance analysis at the conceptual design stage are still missing. To address this gap, this study proposes a novel parallel configuration WEC (PCWEC) with the idea of combining the advantages of multi-DOF OBWEC and parallel structure. The PCWEC energy conversion model is established under irregular wave states. Furthermore, we propose an energy cost-efficiency indicator and perform the performance comparison analysis and simulation experiments. Compared with typical OBWECs, results validate that the proposed PCWEC has the following advantages: (i) a significant power generation increase under the same device scale, (ii) greater optimal output power by power take-off control, and (iii) higher energy cost-efficiency under changing wave states. Such a novel PCWEC design concept improves the current OBWEC's power generation performance and application prospect and offers certain guidance for the future commercial development of OBWECs. [ABSTRACT FROM AUTHOR]

This paper introduces an improved filtering operator based on the first-order derivative Gaussian filtering operator. As the defocus distance decreases, the edges of an image transition from being smooth to sharp. Using the operator proposed in this study, a parameter can be obtained to quantify the degree of edge sharpness, where a smaller value indicates sharper edges. By using the characteristic, we can judge whether the object is near the focal plane. Combining this information, we proposed two focus method. Both of them can avoid the problem of the hill climbing algorithm locating at local extremum points and one of them can locate the watershed between "coarse search" and "fine search" before the sharpness value crosses the peak value, so as to realize the transition from "coarse search" to "fine search" before crossing the peak value and improve focusing efficiency. This is different from previous passive focusing strategies. The final experiment shows that the proposed solutions in this paper is effective. However, the methods proposed in this study are only applicable to incoherent optical microscopy imaging systems and are not suitable for coherent light source microscopy imaging systems. Besides, the prerequisite for the successful implementation of the two proposed focusing strategies in this study is that the target exhibits sharp edges when it is within the focal plane. • A sharpness measurement parameter with a lower bound. • An autofocus strategy for microscope without repeated motion. • An autofocus strategy is more stable than and similar time-consuming to hill-climbed method. [ABSTRACT FROM AUTHOR]

The aim of this study was to investigate whether right ventricular longitudinal strain (RVLS) was independently predictive of higher mortality in patients with coronavirus disease-2019 (COVID-19). RVLS obtained from 2-dimensional speckle-tracking echocardiography has been recently demonstrated to be a more accurate and sensitive tool to estimate right ventricular (RV) function. The prognostic value of RVLS in patients with COVID-19 remains unknown. One hundred twenty consecutive patients with COVID-19 who underwent echocardiographic examinations were enrolled in our study. Conventional RV functional parameters, including RV fractional area change, tricuspid annular plane systolic excursion, and tricuspid tissue Doppler annular velocity, were obtained. RVLS was determined using 2-dimensional speckle-tracking echocardiography. RV function was categorized in tertiles of RVLS. Compared with patients in the highest RVLS tertile, those in the lowest tertile were more likely to have higher heart rate; elevated levels of D-dimer and C-reactive protein; more high-flow oxygen and invasive mechanical ventilation therapy; higher incidence of acute heart injury, acute respiratory distress syndrome, and deep vein thrombosis; and higher mortality. After a median follow-up period of 51 days, 18 patients died. Compared with survivors, nonsurvivors displayed enlarged right heart chambers, diminished RV function, and elevated pulmonary artery systolic pressure. Male sex, acute respiratory distress syndrome, RVLS, RV fractional area change, and tricuspid annular plane systolic excursion were significant univariate predictors of higher risk for mortality (p < 0.05 for all). A Cox model using RVLS (hazard ratio: 1.33; 95% confidence interval [CI]: 1.15 to 1.53; p < 0.001; Akaike information criterion = 129; C-index = 0.89) was found to predict higher mortality more accurately than a model with RV fractional area change (Akaike information criterion = 142, C-index = 0.84) and tricuspid annular plane systolic excursion (Akaike information criterion = 144, C-index = 0.83). The best cutoff value of RVLS for prediction of outcome was −23% (AUC: 0.87; p < 0.001; sensitivity, 94.4%; specificity, 64.7%). RVLS is a powerful predictor of higher mortality in patients with COVID-19. These results support the application of RVLS to identify higher risk patients with COVID-19. [ABSTRACT FROM AUTHOR]

Kunitz-like protease inhibitors (KTIs) have been identified to play critical roles in insect defense, but evidence for their involvement in drought stress is sparse. The aim of this study was to identify and functionally characterize a Kunitz-like protease inhibitor, GsKTI , from the wild soybean (Glycine soja) variety ED059. Expression patterns suggest that drought stress and insect herbivory may induce GsKTI transcript levels. Transgenic Arabidopsis lines overexpressing GsKTI have been shown to exhibit enhanced drought tolerance by regulating the ABA signaling pathway and increasing xylem cell number. Transgenic Arabidopsis leaves overexpressing GsKTI interfered with insect digestion and thus had a negative effect on the growth of Helicoverpa armigera. It is concluded that GsKTI increases resistance to drought stress and insect attack in transgenic Arabidopsis lines. • This study identifies and characterizes the GsKTI gene from the strongly cotton bollworm-resistant wild soybean ED059. • The study investigated the subcellular localization and expression pattern of GsKTI in response to various stresses. • The study found that GsKTI positively regulates drought and cotton bollworm resistance in Arabidopsis. • The GsKTI overexpression Arabidopsis results in insect resistance by severely impairing the immune system of cotton bollworm larvae. [ABSTRACT FROM AUTHOR]

Abstract It is rather important to not only obtain the better detection efficiency for metal ions, but also investigate the change of sensitivity and detection limit in the simultaneous detection. Herein, a novel type of room temperature ion liquid (RTIL)/γ-AlOOH/Fe(OH) 3 composite was prepared. Both the individual and simultaneous determination of Hg(II) and Cu(II) were examined by the composite electrode. The electrode exhibited the lowest limits of detection (LODs) of 0.5 and 0.3 nM for Hg(II) and Cu(II) in simultaneous determination, the highest sensitivities of 64.5 and 65.9 μA/μM, respectively, and the shortest response time. Both Hg(II) and Cu(II) films electroplated on the surface of composite were used to further analyze change of sensitivity and LOD, respectively. The thickness of films influenced the sensitivity and LOD. The proposed electrode was also performed the analysis of soil sample. The analytic method in this study could open up an avenue for the analysis and detection of metal ions, and provide a reference of electrochemical sensor based on metal films. [ABSTRACT FROM AUTHOR]

Strain hardening cementitious composite (SHCC) is an attractive construction material used for reinforced concrete (RC) strengthening, and a simplified method has been previously proposed for evaluating the behavior of SHCC flexural strengthening RC member (Zhang, Engineering Fracture Mechanics 2014; 121–122: 11–27), whereas the load carrying capacity of strengthened RC member is over-estimated using the simplified method. In this study, a numerical approach improved from the aforementioned method is presented for accurately evaluating the behavior of SHCC flexural strengthening RC member, considering the influence of the tensile strain capacity of SHCC, presence of localized concrete cracks and varying SHCC layer thickness, in which a zero-span tensile model with fictitious material is adopted to obtain the average tensile behavior of SHCC layer for strengthening RC member with crack. The effectiveness of the improved numerical approach is confirmed thorough the comparison between experimental and numerical investigations. [ABSTRACT FROM AUTHOR]

Ba 1-x Sm 1-x SnO 3 (BSSO, x = 0.00, 0.02, 0.04, 0.06, 0.08, 0.10 and 0.15) thin films were epitaxially grown on (001) oriented MgO substrates by pulsed laser deposition (PLD) technique. The structure analysis was performed by x-ray diffraction (XRD), including 2theta-omega (2θ-ω) scans, omega (ω) scans, phi (φ) scans, and reciprocal space mapping (RSM). Hall effect measurement shows that the lowest room temperature resistivity value can reach to 7.842 mΩ cm in the 0.04 Sm-doped thin film, while the carrier mobility ( μ ) decreases systematically with increasing Sm doping content. Temperature dependent resistivity behavior indicates that the BSSO films exhibit metal-semiconductor transition in the temperature range of 10–300 K with the doping content up to x = 0.08. Optical transmission spectra measurement shows that all the BSSO films exhibit a high transmittance of more than 80% in the visible range. The increasing of optical band gap E g with the increase of Sm doping content was interpreted by the Burstein-Moss effect and the occurrence of octahedral tilt distorting. Excellent optical and electrical properties mean that the BSSO films have potential applications as transparent and conducting oxide (TCO) material. [ABSTRACT FROM AUTHOR]

This paper presents a numerical approach for evaluating the shear failure behavior of strain hardening cementitious composite (SHCC) member. The developed approach can clarify the respective contributions of both contact stress and fiber bridging stress for the shear stress transfer behavior on crack surface of SHCC member, which thus can disclose the contribution of fibers to local shear of SHCC member. In the numerical approach, a shear stress transfer model and shear lattice system are proposed, in which the shear lattice system can appropriately express the shape of crack surface, and the shear stress transfer model can accurately quantify the transferred shear stress on the crack surface of SHCC member, focusing on the contribution from both matrix’s contact effect and fiber bridging effect respectively. The effectiveness of the numerical approach is confirmed through the comparison between the experimental and numerical results. [ABSTRACT FROM AUTHOR]

Osteoporosis is one of the most prevalent skeletal system diseases; yet, its pathophysiological mechanisms remain elusive. Adipocytes accumulate remarkably in the bone marrow of osteoporotic patients. The potential processes and molecular mechanisms underlying adipogenesis in osteoporotic BMSCs have attracted significant attention as adipocytes and osteoblasts share common precursor cells. Some environmental factors influence bone mass through epigenetic mechanisms; however, the role of epigenetic modifications in osteoporosis is just beginning to be investigated, and there is still little data regarding their involvement. In the current study, we investigated how epigenetic modifications, including DNA methylation and histone modifications, lead to adipogenesis in the bone marrow during osteoporosis. A glucocorticoid-induced osteoporosis (GIO) mouse model was established, and BMSCs were isolated from the bone marrow. Compared with normal BMSCs, osteoporotic BMSCs had significantly increased adipogenesis potential and decreased osteogenesis potential. In osteoporotic BMSCs, PPARγ2 regulatory region DNA hypo-methylation, histone 3 and 4 hyper-acetylation and H3K9 hypo-di-methylation were observed. These epigenetic modifications were involved not only in PPARγ2 expression but also in osteoporotic BMSC adipogenic differentiation potential. We also found that Wnt/β-catenin signal played an important role in the establishment and maintenance of epigenetic modifications at PPARγ2 promoter in osteoporotic BMSCs. Finally, we inhibited adipogenesis and rescued osteogenesis of osteoporotic BMSCs by modulating those epigenetic modifications. Our study provides a deeper insight into the pathophysiology of osteoporosis and identifies PPARγ2 as a new target for osteoporosis therapy based on epigenetic mechanisms. [ABSTRACT FROM AUTHOR]