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The mixtures of cations and anions used in hybrid halide perovskites for high-performance solar cells often undergo element and phase segregation, which limits device lifetime. We adapted Schelling’s model of segregation to study individual cation migration and found that the initial film inhomogeneity accelerates materials degradation. We fabricated perovskite films (FA 1–x Cs x PbI 3 ; where FA is formamidinium) through the addition of selenophene, which led to homogeneous cation distribution that retarded cation aggregation during materials processing and device operation. The resultant devices achieved enhanced efficiency and retained >91% of their initial efficiency after 3190 hours at the maximum power point under 1 sun illumination. We also observe prolonged operational lifetime in devices with initially homogeneous FACsPb(Br 0.13 I 0.87 ) 3 absorbers.

Acute lung injury (ALI) after liver transplantation (LT) may lead to acute respiratory distress syndrome, which is associated with adverse postoperative outcomes, such as prolonged hospital stay, high morbidity, and mortality. Therefore, it is vital to maintain hemodynamic stability and optimize fluid management. However, few studies have reported cardiac output-guided (CO-G) management in pediatric LT.To investigate the effect of CO-G hemodynamic management on early postoperative ALI and hemodynamic stability during pediatric living donor LT.A total of 130 pediatric patients scheduled for elective living donor LT were enrolled as study participants and were assigned to the control group (65 cases) and CO-G group (65 cases). In the CO-G group, CO was considered the target for hemodynamic management. In the control group, hemodynamic management was based on usual perioperative care guided by central venous pressure, continuous invasive arterial pressure, urinary volume,The incidence of early postoperative ALI was 27.7% in the CO-G group, which was significantly lower than that in the control group (44.6%) (CO-G hemodynamic management in pediatric living-donor LT decreases the incidence of early postoperative ALI due to hemodynamic stability through optimized fluid management and appropriate administration of vasopressors and inotropes.

Enhancing the water permeation while maintaining high salt rejection of existing reverse osmosis (RO) membranes remains a considerable challenge. Herein, we proposed to introduce polymer of intrinsic microporosity, PIM-1, into the selective layer of reverse osmosis membranes to break the trade-off effect between permeability and selectivity. A water-soluble a-LPIM-1 of low-molecular-weight and hydroxyl terminals was synthesized. These designed characteristics endowed it with high solubility and reactivity. Then it was mixed with m-phenylenediamine and together served as aqueous monomer to react with organic monomer of trimesoyl chloride via interfacial polymerization. The characterization results exhibited that more “nodule” rather than “leaf” structure formed on RO membrane surface, which indicated that the introduction of the high free-volume of a-LPIM-1 with three dimensional twisted and folded structure into the selective layer effectively caused the frustrated packing between polymer chains. In virtue of this effect, even with reduced surface roughness and unchanged layer thickness, the water permeability of prepared reverse osmosis membranes increased 2.1 times to 62.8 L∙m–2∙h–1 with acceptable NaCl rejection of 97.6%. This attempt developed a new strategy to break the trade-off effect faced by traditional polyamide reverse osmosis membranes.

This review summarizes the latest research progress on strategies for lead leakage control in perovskite solar cells to facilitate the future development of efficient, stable, and environmentally friendly perovskite photovoltaic devices.

Large-diameter link lever butterfly valve is widely used in the transportation and adjustment of fluid media in the marine field. Because the opening and closing process of the link lever butterfly valve is mainly realized by the internal connecting rod mechanism, and it always exists in the fluid domain to affect the flow performance of the valve. It is necessary to optimize the connecting rod mechanism inside the valve. There are many structural safety problems in the connecting rod mechanism during the valve opening and closing process, such as large starting torque, vortex and turbulence near the valve disc causing resonance of the device, etc. This paper proposes a method to optimize the internal structure of the link lever butterfly valve to improve the flow performance of the valve while meeting the structural safety. The surrogate model is combined with finite element method (FEM) and computational fluid dynamics (CFD) analysis to improve optimization efficiency. The Response surface method (RSM) model is used to replace the Kriging model with insufficient accuracy, and build the combined surrogate model based on the global error criterion. The optimization algorithm combined with MIGA and NLPQL is used to obtain the best results of internal structural variables. The accuracy of the combined surrogate model is verified through FEM and CFD analysis. The results show that the flow performance of the link lever butterfly valve is greatly increased and combined surrogate model can effectively replace the finite element model to solve the optimization problem.

Purpose Myocardial salvage (MS) and myocardial salvage index(MSI) assessed by Gated SPECT myocardial perfusion imaging (GSMPI) have demonstrated prognostic significance in ST-segment-elevation myocardial infarction(STEMI). However, this method requires GSMPI after tracer injection before percutaneous coronary intervention(PCI), so make it limited in clinical practice. This study aims to obtain the MSI by simple GSMPI early after primary PCI (PPCI) in STEMI , evaluate the predictive significance of MSI in efficacy of PCI and major adverse cardiovascular events (MACEs). Apply the scoring evaluation method innovatively different from the previous method, and confirm the former’s advantage. Methods 62 patients with STEMI, who underwent GSMPI after PPCI. MS and MSI were obtained by scoring and the number evaluation method,respectively. Left ventricular ejection fraction (LVEF) before discharge and 6 months after PCI were estimated by cardiac ultrasound.Patients whose LVEF increased by at least 20% compared to baseline were defined as PCI-effective group. Compare the MS ,MSI and their prognostic significancein PCI efficacy between the two evaluation methods. Patients were divided into two groups according to the median MSI(0.27), over a median follow-up period of 270(128-366) days, estimate the prognostic significance of MSI on MACEs. Results The MS and MSI were relevant [ r(MS)=0.491, r(MSI)=0.779, P< .05], but significant different by the two methods (P < .01). MSI by the scoring method showed the stronger prognostic value in PCI efficacy with AUC of 0.793, sensitivity: 71.40%, specificity: 73.70% than the number method with AUC of 0.634, sensitivity: 43.80%, specificity: 94.40% (all PP< .05). Conclusion MSI obtained from an simple GSMPI after re-perfusion on scoring evaluation method is a reliable prognostic indicator which provides feasible way to predict the PPCI efficacy and MACEs in STEMI patients.

A laboratory experiment was conducted to investigate the impacts of freeze-thaw intensity (-5-5 ℃, -10-5 ℃) and frequency (1, 5, 10, 15 times) on the community structure of soil arthropod in permafrost zone, Great Hing'an Mountains with the 5 ℃ as control. A total of 4198 individuals of soil arthropod were extracted, belonging to 4 classes, 9 orders, 24 families and 33 genera. The results showed that the number of individuals and groups of soil arthropod decreased significantly in the treatment with high frost intensity (-10-5 ℃), while the individuals of some taxa increased in the treatment with low frost intensity (-5-5 ℃) after the first freeze-thaw incubation. The group number, Margalef index and Shannon index decreased with the increases of freeze-thaw cycling times in low frost intensity treatment, while did not change regularly in high frost intensity treatment. Larva stage was a kind of survival strategy for arthropod to resist low temperature stress, with Acari showing stronger cold tolerance. Different responses of soil arthropod to freeze-thaw cycles, synergistic effect among species and soil environment were factors affecting the structure of soil arthropod community. This study could provide scientific data and theoretical basis for the research and conservation of soil arthropod diversity in the permafrost zone in mid-high latitudes.利用室内模拟冻融试验,以5 ℃未冻融为对照,研究冻融强度(-5～5 ℃、-10～5 ℃)和冻融频次(1、5、10、15次)对我国大兴安岭多年冻土区土壤节肢动物群落结构的影响。结果表明: 试验共分离到土壤节肢动物4198只,隶属于4纲9目24 科 33属;强冻融(-10～5 ℃)显著降低了土壤节肢动物的个体数和类群数,而轻冻融(-5～5 ℃)尤其是短期(1次冻融循环)处理则使某些类群的个体数增加;在轻冻融处理中类群数、Margalef指数和Shannon指数随着冻融频次的增加显著降低,但在强冻融处理中并未表现出规律性变化;越冬虫态是土壤节肢动物抵御低温胁迫的生存策略之一,同时蜱螨亚纲具有较好的耐寒性。土壤节肢动物对冻融作用的差异性响应、物种间的协同作用以及土壤环境均是影响其群落组成的主要因素。本研究将为我国中高纬多年冻土区土壤节肢动物多样性研究和保护提供数据支持和理论依据。.

Perovskite solar cells (PSCs) have become a promising candidate for the next-generation photovoltaic technologies. As an essential element for high-efficiency PSCs however, the heavy metal Pb is soluble in water, causing a serious threat to the environment and human health. Due to the weak ionic bonding in three-dimensional (3D) perovskites, drastic structure decomposition occurs when immersing the perovskite film in water, which accelerates the Pb leakage. By introducing the chemically stable Dion-Jacobson (DJ) 2D perovskite at the 3D perovskite surface, the film dissolution is significantly slowed down, which retards lead leakage. As a result, the Pb contamination is dramatically reduced under various extreme conditions. In addition, the PSCs device deliver a power conversion efficiency (PCE) of 23.6 % and retain over 95 % of their initial PCE after the maximum power point tracking for over 1100 h.

This paper focuses on the weight reduction optimization of a forearm of a bucket-wheel stacker reclaimer considering uncertainties of structural parameters, material properties, loads, and surrogate model. However, the optimization problem is a high-dimensional problem, with dozens of independent variables, which has negative effects on the optimization efficiency. Considering that millions of iterations are required for the reliability-based optimization, the finite element model can cause overwhelming computational cost. In addition, due to its complex structure and working conditions, multiple uncertainties exist in practical applications and affect the reliability of a design, especially the uncertainty of the surrogate model. To address these challenges, the sensitivity analysis is performed to improve the optimization efficiency by selecting main factors. The Kriging model with high accuracy is constructed to reduce the computational cost. In order to improve the optimization efficiency further, the deterministic optimization is performed firstly, and the optimal design is used as the initial point of the reliability-based optimization algorithm. For estimating the reliability, the multiple uncertainty models are constructed. Finally, according to the design requirements and taking the multiple uncertainties into account, the reliability-based optimization is proposed and carried out. The result proves that the weight is reduced greatly and the reliability is kept at a high level.

Objective: DBPR108, a novel dipeptidyl-peptidase-4 inhibitor, has shown great antihyperglycemic effect in animal models. This study was to evaluate the efficacy and safety of DBPR108 monotherapy in...

The biological corrosion behavior and mechanical properties of Mg89-xY4Zn2Li5Mnx (x = 0, 0.5, 1, 1.5 and 2 at.%) alloy with long-period stacking ordered (LPSO) structure were investigated in this work. The magnesium matrix and the eutectic phase of Mg88Y4Zn2Li5Mn1 alloy are effectively refined by the grain boundary segregation of Mn, and the average size of matrix and the eutectic phase decreased by 66 % and 74 %, respectively. The ultimate tensile strength (UTS) and elongation enhanced by 36 % and 55 %, respectively. The corrosion rates obtained by weight loss and hydrogen evolution of Mg88Y4Zn2Li5Mn1 alloy were 79 % and 84 % lower than that of Mg88Y4Zn2Li5 alloy. Additionally, Mg88Y4Zn2Li5Mn1 alloy also presents superior corrosion behavior in electrochemical test. It is verified that Mn plays a positive role in both corrosion and mechanical properties of the Mg88Y4Zn2Li5Mn1 alloy, which provides a reference for further experimental work.

Black hole feedback has been widely implemented as the key recipe to quench star formation in massive galaxies in modern semi-analytic models and hydrodynamical simulations. As the theoretical details surrounding the accretion and feedback of black holes continue to be refined, various feedback models have been implemented across simulations, with notable differences in their outcomes. Yet, most of these simulations have successfully reproduced some observations, such as stellar mass function and star formation rate density in the local Universe. We use the recent observation on the change of neutral hydrogen gas mass (including both ${\rm H_2}$ and ${\rm HI}$) with star formation rate of massive central disc galaxies as a critical constraint of black hole feedback models across several simulations. We find that the predictions of IllustrisTNG agree with the observations much better than the other models tested in this work. This favors IllustrisTNG's treatment of active galactic nuclei - where kinetic winds are driven by black holes at low accretion rates - as more plausible amongst those we test. In turn, this also indirectly supports the idea that the massive central disc galaxy population in the local Universe was likely quenched by AGN feedback., Comment: 15 pages, 3+4 figures, accepted for publication in ApJ

The objective of this paper is to minimize the weight of the forearm of the bucket-wheel stacker reclaimer on the premise of guaranteeing strength, stiffness, and non-resonance. Because the stacking and reclaiming are inseparable from the motion of the forearm, the consumed energy is positively proportional to the self-weight and the forearm supports a lot of loads during the working process; it is necessary to minimize the weight under the requirements of strength, stiffness, and non-resonance. However, it is a high-dimensional problem, and it is of low efficiency when the finite element model is used for optimization. Morris method is used to perform the sensitivity analysis on all the variables. Those with great influence, named main factors, are screened out in order to decrease the number of variables taken into account. Surrogate models are introduced to improve the efficiency of optimization. Herein, Kriging models of the weight, the maximum stress, the maximum displacement, the first-order nature frequency under no-load situation, and the second nature frequency under full-load situation are constructed. In order to improve the model with poor precision, the sequential multi-point infill criterion is introduced. Finally, the weight reduction optimization is performed based on the constructed Kriging models. Compared with the initial design, the weight is reduced greatly. Besides, the Kriging models are of excellent accuracy, which proves that Kriging models or surrogate models are effective substitutes for expensive finite element models to deal with optimization problems.

MicroRNAs (miRNAs) are involved in lymphoma progression by regulating the tumor microenvironment. Serum miR130b is overexpressed in diffuse large B-cell lymphoma (DLBCL), inducing Th17 cell alterations. To further illustrate its biological significance and therapeutic rationale, miR130b was detected by quantitative real-time PCR in the serum samples of 532 newly diagnosed DLBCL patients. The mechanism of miR130b on lymphoma progression and the tumor microenvironment was investigated both in vitro and in vivo. Therapeutic targeting miR130b was also evaluated, including OX40 agonistic antibody and lipid nanoparticles (LNPs)-miR130b antagomir. The results showed that serum miR130b significantly correlated with tumor miR130b and serum interleukin-17, indicating lymphoma relapse and inferior survival of DLBCL patients. MiR130b overexpression altered tumor microenvironment signaling pathways and increased Th17 cell activity. As mechanism of action, miR130b downregulated tumor OX40L expression by directly targeting IFNAR1/p-STAT1 axis, recruiting Th17 cells via OX40/OX40L interaction, thereby promoting immunosuppressive function of Th17 cells. In co-culture systems of B-lymphoma cells with immune cells, miR130b inhibited lymphoma cell autophagy, which could be counteracted by OX40 agonistic antibody and LNPs-miR130b antagomir. In murine xenograft model established with subcutaneous injection of A20 cells, both OX40 agonistic antibody and LNPs-miR130b antagomir remarkably inhibited Th17 cells and retarded miR130b-overexpressing tumor growth. In conclusion, as an oncogenic biomarker of DLBCL, miR130b was related to lymphoma progression through modulating OX40/OX40L-mediated lymphoma cell interaction with Th17 cells, attributing to B-cell lymphoma sensitivity towards OX40 agonistic antibody. Targeting miR130b using LNPs-miR130b antagomir could also be a potential immunotherapeutic strategy in treating OX40-altered lymphoid malignancies.

Environment is one of the key external drivers of the galaxies, while active galactic nucleus (AGN) is one of the key internal drivers. Both of them play fundamental roles in regulating the formation and evolution of galaxies. We explore the interrelationship between environment and AGN in SDSS. At a given stellar mass, the specific star formation rate distribution of the AGN host galaxies remains unchanged with over-density, with the peak of the distribution around the Green Valley. We show that, at a given stellar mass, the AGN fraction that has been commonly used in previous studies (defined as the number of AGNs relative to all galaxies including passive and star forming ones) does decrease with increasing over-density for satellites. This is largely due to the fact that the fraction of passive galaxies strongly depends on environment. In order to investigate the intrinsic correlation between AGN and environment, especially under the assumption that AGN feedback is responsible for star formation quenching, the AGN fraction should be defined as the number of AGNs relative to the star-forming galaxies only. With the new definition, we find little dependence of AGN fraction on over-density, central/satellite, and group halo mass. There is only marginal evidence that AGN may prefer denser regions, which is possibly due to more frequent interaction of galaxies or higher merger rate in groups. Our results support the scenario that internal secular evolution is the predominant mechanism of triggering AGN activity, while external environment related processes only play a minor role., Accepted for publication in MNRAS, submitted on June 4. 11 pages, 7 figures

To study the effects of replacing alfalfa hay with Moringa oleifera leaves and peduncles in diets on intake, digestibility, and rumen fermentation in dairy cows, eight multiparous Holsteins cows with similar DIM (day in milk, 93 ± 18 d) and body weights (624 ± 38 kg) were used in a crossover design with two dietary treatments. The treatment diets contained similar concentrate mixtures and corn silage but different proportions of M. oleifera leaves and peduncles. The treatments were a (1) control diet (0% M. oleifera feed) and (2) M. oleifera diet (10.85% M. oleifera feed). The M. oleifera feed used M. oleifera leaves and M. oleifera peduncles at a ratio of 3:2 and replaced portions of alfalfa hay. The experimental period was 18 d, with 15 d for treatment adaptation and 3 d for data collection. Compared with the control diet, the dry matter intake and apparent digestibility of dry matter, crude protein, acid detergent fiber and neutral detergent fiber in the M. oleifera diet were significantly increased. No difference was observed in ruminal pH; however, the ammonia-N concentrate was lower for the M. oleifera diet than the control diet. The concentrations of total ruminal volatile fatty acids, acetate, propionate, and butyrate were higher in cows fed the M. oleifera diet than in those fed the control diet. The results of ruminal microbes showed that those consuming the M. oleifera diet had greater relative expression level of Fibrobacter succinogenes, Butyrivibrio fibrisolvens, Ruminobacter amylophilus, Streptococcus bovis, Prevotella ruminicola which were observed for the control diet than the M. oleifera diet. These results show that the M. oleifera diet can improve intake and apparent digestibility of nutrients, and rumen fermentation in dairy cows.

BackgroundCOVID-19 affects healthcare resource allocation, which could lead to treatment delay and poor outcomes in patients with acute myocardial infarction (AMI). We assessed the impact of the COVID-19 pandemic on AMI outcomes.MethodsWe compared outcomes of patients admitted for acute ST-elevation MI (STEMI) and non-STEMI (NSTEMI) during a non-COVID-19 pandemic period (January–February 2019; Group 1, n = 254) and a COVID-19 pandemic period (January–February 2020; Group 2, n = 124).ResultsFor STEMI patients, the median of first medical contact (FMC) time, door-to-balloon time, and total myocardial ischemia time were significantly longer in Group 2 patients (allp p p > 0.05). For NSTEMI patients, Group 2 patients had a higher rate of conservative therapy, a lower rate of reperfusion therapy, and longer FMC times (allp p ConclusionsCOVID-19 pandemic causes treatment delay in AMI patients and potentially leads to poor clinical outcome in NSTEMI patients. Thrombolytic therapy should be initiated without delay for STEMI when coronary intervention is not readily available; for NSTEMI patients, outcomes of invasive reperfusion were better than medical treatment.

The phenomenological study of evolving galaxy populations has shown that star forming galaxies can be quenched by two distinct processes: mass quenching and environment quenching (Peng et al. 2010). To explore the mass quenching process in local galaxies, we study the massive central disk galaxies with stellar mass above the Schechter characteristic mass. In Zhang et al. (2019), we showed that during the quenching of the massive central disk galaxies as their star formation rate (SFR) decreases, their molecular gas mass and star formation efficiency drop rapidly, but their HI gas mass remains surprisingly constant. To identify the underlying physical mechanisms, in this work we analyze the change during quenching of various structure parameters, bar frequency, and active galactic nucleus (AGN) activity. We find three closely related facts. On average, as SFR decreases in these galaxies: (1) they become progressively more compact, indicated by their significantly increasing concentration index, bulge-to-total mass ratio, and central velocity dispersion, which are mainly driven by the growth and compaction of their bulge component; (2) the frequency of barred galaxies increases dramatically, and at a given concentration index the barred galaxies have a significantly higher quiescent fraction than unbarred galaxies, implying that the galactic bar may play an important role in mass quenching; and (3) the "AGN" frequency increases dramatically from 10% on the main sequence to almost 100% for the most quiescent galaxies, which is mainly driven by the sharp increase of LINERs. These observational results lead to a self-consistent picture of how mass quenching operates., Comment: 20 pages, 11 figures. Published in ApJ

Star formation and quenching are two of the most important processes in galaxy formation and evolution. We explore in the local Universe the interrelationships among key integrated galaxy properties, including stellar mass $M_*$, star formation rate (SFR), specific SFR (sSFR), molecular gas mass $M_{\rm H_2}$, star formation efficiency (SFE) of the molecular gas and molecular gas to stellar mass ratio $\mu$. We aim to identify the most fundamental scaling relations among these key galaxy properties and their interrelationships. We show the integrated $M_{\rm H_2}$-SFR, SFR-$M_*$ and $M_{\rm H_2}$-$M_*$ relation can be simply transformed from the $\mu$-sSFR, SFE-$\mu$ and SFE-sSFR relation, respectively. The transformation, in principle, can increase or decrease the scatter of each relation. Interestingly, we find the latter three relations all have significantly smaller scatter than the former three corresponding relations. We show the probability to achieve the observed small scatter by accident is extremely close to zero. This suggests that the smaller scatters of the latter three relations are driven by a more fundamental physical connection among these quantities. We then show the large scatters in the former relations are due to their systematic dependence on other galaxy properties, and on star formation and quenching process. We propose the sSFR-$\mu$-SFE relation as the Fundamental Formation Relation (FFR), which governs the star formation and quenching process, and provides a simple framework to study galaxy evolution. Other scaling relations, including integrated Kennicutt-Schmidt law, star-forming main sequence and molecular gas main sequence, can all be derived from the FFR., Comment: This is the revised version accepted for publication in ApJ