Electrochemically Deposited CZTSSe Thin Films for Monolithic Perovskite Tandem Solar Cells with Efficiencies Over 17%

In spite of the high potential economic feasibility of the tandem solar cells consisting of the halide perovskite and the kesterite Cu2ZnSn(S,Se)4(CZTSSe),they have rarely been demonstrated due to the difficulty in implementing solution-processed perovskite top cell on the rough surface of the bottom cells.Here,we firstly demonstrate an efficient monolithic two-terminal perovskite/CZTSSe tandem solar cell by significantly reducing the surface roughness of the electrochemically deposited CZTSSe bottom cell.The surface roughness(R_(rms))of the CZTSSe thin film could be reduced from 424 to 86 nm by using the potentiostatic mode rather than using the conventional galvanostatic mode,which can be further reduced to 22 nm after the subsequent ion-milling process.The perovskite top cell with a bandgap of 1.65 eV could be prepared using a solution process on the flattened CZTSSe bottom cell,resulting in the efficient perovskite/CZTSSe tandem solar cells.After the current matching between two subcells involving the thickness control of the perovskite layer,the best performing tandem device exhibited a high conversion efficiency of 17.5%without the hysteresis effect.

Bacteriophage cocktail supplementation improves growth performance,gut microbiome and production traits in broiler chickens

Background:Effective antibiotic alternatives are urgently needed in the poultry industry to control disease outbreaks.Phage therapy mainly utilizes lytic phages to kill their respective bacterial hosts and can be an attractive solution to combating the emergence of antibiotic resistance in livestock.Methods:Five hundred and four,one-day-old broilers(Ross 308)were allotted to 1 of 4 treatment groups in a completely randomized design.Treatments consisted of CON(basal diet),PC(CON+0.025%Avilamax®),BP 0.05(CON+0.05%bacteriophage),and BP 0.10(CON+0.10%bacteriophage).Results:A significant linear effect on body weight gain(BWG)was observed during days 1–7,days 22–35,and cumulatively in bacteriophage(BP)supplemented groups.The BWG tended to be higher(P=0.08)and the feed intake(FI)was increased(P=0.017)in the PC group over CON group.A greater(P=0.016)BWG and trends in increased FI(P=0.06)were observed in the experiment in birds fed PC than CON diet.At the genus level,the relative abundance of Lactobacillus was decreased in PC(65.28%),while it was similar in BP 0.05 and BP 0.10(90.65%,86.72%)compared to CON(90.19%).At the species level,the relative abundance of Lactobacillus salivarus was higher in BP 0.05(40.15%)and BP 0.10(38.58%)compared to the CON(20.04%)and PC(18.05%).A linear reduction in the weight of bursa of Fabricius(P=0.022)and spleen(P=0.052)was observed in birds fed graded level of BP and an increase(P=0.059)in the weight of gizzard was observed in birds fed PC over BP diets.Linear and quadratic responses were observed in redness of breast muscle color in birds fed graded level of BP.Conclusions:The inclusion of the 0.05%and 0.1%BP cocktail linearly improved broiler weight during the first 7 days,22–35 days and cumulatively,whereas 0.05%BP addition was sufficient for supporting immune organs,bursa and spleen as well as enhancing gut microbiome,indicating the efficacy of 0.05%BP as a substitute antibiotic growth promoter in broiler diets.

A recent advances of blue perovskite light emitting diodes for next generation displays

The halide perovskite blue light emitting diodes(PeLEDs)attracted many researchers because of its fascinating optoelectrical properties.This review introduces the recent progress of blue PeLEDs which focuses on emissive layers and interlayers.The emissive layer covers three types of perovskite structures:perovskite nanocrystals(PeNCs),2-dimensional(2D)and quasi-2D perovskites,and bulk(3D)perovskites.We will discuss about the remaining challenges of blue PeLEDs,such as limited performances,device instability issues,which should be solved for blue PeLEDs to realize next generation displays.

Environmental Sound Event Detection in Wireless Acoustic Sensor Networks for Home Telemonitoring

In this paper, we present an approach to improve the accuracy of environmental sound event detection in a wireless acoustic sensor network for home monitoring. Wireless acoustic sensor nodes can capture sounds in the home and simultaneously deliver them to a sink node for sound event detection. The proposed approach is mainly composed of three modules, including signal estimation, reliable sensor channel selection, and sound event detection. During signal estimation, lost packets are recovered to improve the signal quality. Next, reliable channels are selected using a multi-channel cross-correlation coefficient to improve the computational efficiency for distant sound event detection without sacrificing performance. Finally, the signals of the selected two channels are used for environmental sound event detection based on bidirectional gated recurrent neural networks using two-channel audio features. Experiments show that the proposed approach achieves superior performances compared to the baseline.

Passivation engineering via silica‐encapsulated quantum dots for highly sensitive photodetection

Organometal halide perovskites are promising semiconducting materials for photodetectors because of their favorable optoelectrical properties.Although nanoscale perovskite materials such as quantum dots(QDs)show novel behavior,they have intrinsic stability issues.In this study,an effectively silane barrier-capped quantum dot(QD@APDEMS)is thinly applied onto a bulk perovskite photosensitive layer for use in photodetectors.QD@APDEMS is synthesized with a silane ligand with hydrophobic CH_(3)-terminal groups,resulting in excellent dispersibility and durability to enable effective coating.The introduction of the QD@APDEMS layer results in the formation of a lowdefect perovskite film with enlarged grains.This is attributed to the grain boundary interconnection effect via interaction between the functional groups of QD@APDEMS and uncoordinated Pb^(2+)in grain boundaries.By passivating the grain boundaries,where various trap sites are distributed,hole chargecarrier injection and shunt leakage can be suppressed.Also,from the energy point of view,the deep highest occupied molecular orbital(HOMO)level of QD@APDEMS can work as a hole charge injection barrier.Improved charge dynamics(generation,transfer,and recombination properties)and reduced trap density of QD@APDEMS are demonstrated.When this perovskite film is used in a photodetector,the device performance(especially the detectivity)stands out among existing perovskites evaluated for energy sensing device applications.

Tailored BiVO_(4)/In_(2)O_(3)nanostructures with boosted charge separation ability toward unassisted water splitting

The development of new heterostructures with high photoactivity is a breakthrough for the limitation of solar-driven water splitting.Here,we first introduce indium oxide(In_(2)O_(3))nanorods(NRs)as a novel electron transport layer for bismuth vanadate(BiVO_(4))with a short charge diffusion length.In_(2)O_(3)NRs reinforce the electron transport and hole blocking of BiVO_(4),surpassing the state-of-the-art photoelectrochemical performances of BiVO_(4)-based photoanodes.Also,a tannin-nickel-iron complex(TANF)is used as an oxygen evolution catalyst to speed up the reaction kinetics.The final TANF/BiVO_(4)/In_(2)O_(3)NR photoanode generates photocurrent densities of 7.1 mAcm^(−2) in sulfite oxidation and 4.2 mA cm^(−2) in water oxidation at 1.23 V versus the reversible hydrogen electrode.Furthermore,the“artificial leaf,”which is a tandem cell with a perovskite/silicon solar cell,shows a solar-to-hydrogen conversion efficiency of 6.2%for unbiased solar water splitting.We reveal significant advances in the photoactivity of TANF/BiVO_(4)/In_(2)O_(3)NRs from the tailored nanostructure and band structure for charge dynamics.

Modeling and implementation of tandem polymer solar cells using wide-bandgap front cells

Tandem device architectures offer a route to greatly increase the maximum possible power conversion efficiencies(PCEs)of polymer solar cells,however,the complexity of tandem cell device fabrication(such as selecting bandgaps of the front and back cells,current matching,thickness,and recombination layer optimization)often result in lower PCEs than are observed in single-junction devices.In this study,we analyze the influence of front cell and back cell bandgaps and use transfer matrix modeling to rationally design and optimize effective tandem solar cell structures before actual device fabrication.Our approach allows us to estimate tandem device parameters based on known absorption coefficients and open-circuit voltages of different active layer materials and design devices without wasting valuable time and materials.Using this approach,we have investigated a series of wide bandgap,high voltage photovoltaic polymers as front cells in tandem devices with PTB7-Th as a back cell.In this way,we have been able to demonstrate tandem devices with PCE of up to 12.8%with minimal consumption of valuable photoactive materials in tandem device optimization.This value represents one of the highest PCE values to date for fullerene-based tandem solar cells.

Developing a Breast Cancer Resistance Protein Substrate Prediction System Using Deep Features and LDA

Breast cancer resistance protein(BCRP)is an important resistance protein that significantly impacts anticancer drug discovery,treatment,and rehabilitation.Early identification of BCRP substrates is quite a challenging task.This study aims to predict early substrate structure,which can help to optimize anticancer drug development and clinical diagnosis.For this study,a novel intelligent approach-based methodology is developed by modifying the ResNet101 model using transfer learning(TL)for automatic deep feature(DF)extraction followed by classification with linear discriminant analysis algorithm(TLRNDF-LDA).This study utilized structural fingerprints,which are exploited by DF contrary to conventional molecular descriptors.The proposed in silico model achieved an outstanding accuracy performance of 98.56%on test data compared to other state-of-the-art approaches using standard quality measures.Furthermore,the model’s efficacy is validated via a statistical analysisANOVAtest.It is demonstrated that the developedmodel can be used effectively for early prediction of the substrate structure.The pipeline of this study is flexible and can be extended for in vitro assessment efficacy of anticancer drug response,identification of BCRP functions in transport experiments,and prediction of prostate or lung cancer cell lines.

Induction of vascular endothelial growth factor receptor expression in human umbilical vein endothelial cells after repeated bevacizumab treatment in vitro

AIM： To investigate the mechanism underlying the loss of responsiveness to anti-vascular endothelial growth factor（VEGF） treatment after repeated injections for choroidal neovascularization, VEGF and VEGF receptor（VEGFR） expressions were evaluated following repeated bevacizumab treatments in hypoxic human umbilical vein endothelial cells（HUVECs） in vitro.METHODS： HUVECs were incubated under hypoxic conditions in two media of different bevacizumab concentrations（1.0 or 2.5 mg/m L） for 17 h, and then in a new medium without bevacizumab for 7h. This procedure was repeated twice more. A culture with an identical volume of excipients served as the control. Cytotoxicity and cell proliferation were assessed using 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyl tetrazolium bromide and Ki-67 assays, respectively. Levels of VEGF and VEGFR were assessed using enzyme-linked immunosorbent assay and Western blot respectively.RESULTS： Cytotoxic effects were not reported for either bevacizumab concentration. Cell proliferation was not reduced after anti-VEGF treatments. VEGF level after single treatment was significantly higher than that of the control and after repeated treatments. Phosphorylated VEGFR-2 expression increased significantly after singleand repeated bevacizumab treatments compared with the control. The 1.0 mg/m L bevacizumab induced significantly higher expressions of VEGFR-2 than the 2.5 mg/m L in single and repeated treatment groups.CONCLUSION： Bevacizumab treatment of HUVECs elevated VEGFR expression in both single and repeated treatments, indicating a mechanism for the reduced efficacy of anti-VEGF therapy in ocular neovascular disorders.

Deep learning-based virtual staining,segmentation,and classification in label-free photoacoustic histology of human specimens

In pathological diagnostics,histological images highlight the oncological features of excised specimens,but they require laborious and costly staining procedures.Despite recent innovations in label-free microscopy that simplify complex staining procedures,technical limitations and inadequate histological visualization are still problems in clinical settings.Here,we demonstrate an interconnected deep learning(DL)-based framework for performing automated virtual staining,segmentation,and classification in label-free photoacoustic histology(PAH)of human specimens.The framework comprises three components:(1)an explainable contrastive unpaired translation(E-CUT)method for virtual H&E(VHE)staining,(2)an U-net architecture for feature segmentation,and(3)a DL-based stepwise feature fusion method(StepFF)for classification.The framework demonstrates promising performance at each step of its application to human liver cancers.In virtual staining,the E-CUT preserves the morphological aspects of the cell nucleus and cytoplasm,making VHE images highly similar to real H&E ones.In segmentation,various features(e.g.,the cell area,number of cells,and the distance between cell nuclei)have been successfully segmented in VHE images.Finally,by using deep feature vectors from PAH,VHE,and segmented images,StepFF has achieved a 98.00%classification accuracy,compared to the 94.80%accuracy of conventional PAH classification.In particular,StepFF’s classification reached a sensitivity of 100%based on the evaluation of three pathologists,demonstrating its applicability in real clinical settings.This series of DL methods for label-free PAH has great potential as a practical clinical strategy for digital pathology.

胃十二指肠支架置入术

胃出口梗阻是晚期胰腺、胃和十二指肠恶性肿瘤的一种晚期并发症。胃出口梗阻患者会出现难治性恶心、呕吐和厌食,进而可能导致电解质失衡、脱水和营养不良。此外,这些患者持续存在误吸和肺炎的风险。传统上,这些梗阻大多采用手术治疗。然而,许多患者由于初始评估时的身体状况不佳而不适合接受搭桥手术。此外,其发病率和死亡率显著较高,并与症状持续或延迟缓解和住院时间延长相关。球囊扩张术和金属支架置入已成功应用于不适合手术的患者。文章将对其适应证、禁忌证、技术、结果及争议进行综述。

Super-resolution localization photoacoustic microscopy using intrinsic red blood cells as contrast absorbers

Photoacoustic microscopy(PAM)has become a premier microscopy tool that can provide the anatomical,functional,and molecular information of animals and humans in vivo.However,conventional PAM systems suffer from limited temporal and/or spatial resolution.Here,we present a fast PAM system and an agent-free localization method based on a stable and commercial galvanometer scanner with a custom-made scanning mirror(L-PAM-GS).This novel hardware implementation enhances the temporal resolution significantly while maintaining a high signal-to-noise ratio(SNR).These improvements allow us to photoacoustically and noninvasively observe the microvasculatures of small animals and humans in vivo.Furthermore,the functional hemodynamics,namely,the blood flow rate in the microvasculature,is successfully monitored and quantified in vivo.More importantly,thanks to the high SNR and fast B-mode rate(500 Hz),by localizing photoacoustic signals from captured red blood cells without any contrast agent,unresolved microvessels are clearly distinguished,and the spatial resolution is improved by a factor of 2.5 in vivo.LPAM-GS has great potential in various fields,such as neurology,oncology,and pathology.

Deep learning acceleration of multiscale superresolution localization photoacoustic imaging

A superresolution imaging approach that localizes very small targets,such as red blood cells or droplets of injected photoacoustic dye,has significantly improved spatial resolution in various biological and medical imaging modalities.However,this superior spatial resolution is achieved by sacrificing temporal resolution because many raw image frames,each containing the localization target,must be superimposed to form a sufficiently sampled high-density superresolution image.Here,we demonstrate a computational strategy based on deep neural networks(DNNs)to reconstruct high-density superresolution images from far fewer raw image frames.The localization strategy can be applied for both 3D label-free localization optical-resolution photoacoustic microscopy(OR-PAM)and 2D labeled localization photoacoustic computed tomography(PACT).For the former,the required number of raw volumetric frames is reduced from tens to fewer than ten.For the latter,the required number of raw 2D frames is reduced by 12 fold.Therefore,our proposed method has simultaneously improved temporal(via the DNN)and spatial(via the localization method)resolutions in both label-free microscopy and labeled tomography.Deep-learning powered localization PA imaging can potentially provide a practical tool in preclinical and clinical studies requiring fast temporal and fine spatial resolutions.

Downregulated miR-18b-5p triggers apoptosis by inhibition of calcium signaling and neuronal cell differentiation in transgenic SOD1(G93A)mice and SOD1(G17S and G86S)ALS patients

Background:MicroRNAs(miRNAs)are endogenous non-coding RNAS that regulate gene expression at the post-transcriptional level and are key modulators in neurodegenerative diseases.Overexpressed miRNAs play an important role in amyotrophic lateral sclerosis(ALS);however,the pathogenic mechanisms of deregulated miRNAS are still unclear.Methods:We aimed to assess the dysfunction of RNAS or miRNAs in fALS(SOD1 mutations).We compared the RNA-seq of subcellular fractions in NSC-34 WT(hSOD1)and MT(hSOD1(G93A))cells to find altered RNAs or miRNAs.We identified that Hif1a and Mef2c were upregulated,and Mctp1 and Rarb were downregulated in the cytoplasm of NSC-34 MT cells.Results:SOD1 mutations decreased the level of miR-18b-5p.Induced Hif1a which is the target for miR-18b increased Mef2c expression as a transcription factor.Mef2c upregulated miR-206 as a transcription factor.Inhibition of Mctp1 and Rarb,which are targets of miR-206,induced intracellular Ca^2+ levels and reduced cell differentiation,respectively.The miR-18b-5p pathway was also observed in G93A Tg mice,fALS(G86S)patient,and iPSC-derived motor neurons from fALS(G17S)patient.Conclusions:Our data indicate that SOD1 mutation decreases miR-18b-5p,which sequentially regulates Hif1a,Mef2c,miR-206,Mctp1 and Rarb in fALS-linked SOD1 mutation.These results provide new insights into the downregulation of miR-18b-5p-dependent pathogenic mechanisms of ALS.

Semi-crystalline photovoltaic polymers with siloxane-terminated hybrid side-chains

Three types of semi-cry stalline photovoltaic polymers were synthesized by incorporating a siloxane-terminated organic/inorganic hybrid side-chain and changing the number of fluorine substituents.A branch point away from a polymer main backbone in the siloxane-containing side-chains and the intra-and/or interchain noncovalent coulombic interactions enhance a chain planarity and facile interchain organization.The resulting polymers formed strongly agglomerated films with high roughness,suggesting strong intermolecular interactions.The optical band gap of ca.1.7 eV was measured for all polymers with a pronounced shoulder peak due to tight π-π stacking.With increasing the fluorine substituents,the frontier energy levels decreased and preferential face-on orientation was observed.The siloxane-terminated side-chains and fluorine substitution promoted the intermolecular packing,showing well resolved lamellar scatterings up to(300) for this series of polymers in the grazing incidence wide angle X-ray scattering measurements.The PPsiDTBT,PPsiDTFBT and PPsiDT2 FBT devices showed a power conversion efficiency of 3.16%,4.40%and 5.65%,respectively,by blending with PC_(71)BM.Langevin-type bimolecular charge recombination was similar for three polymeric solar cells.The main loss in the photocurrent generation for PPsiDTBT:PC_(71)BM was interpreted to originate from the trap assisted charge recombination by measuring light-intensity dependent short-circuit current density(J_(SC)) and open-circuit voltage(V_(Oc)).Our results provide a new insight into the rational selection of solubilizing substituents for optimizing crystalline interchain packing with appropriate miscibility with PC71 BM for further optimizing polymer solar cells.