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The SnZn defect passivation and heterojunction interface energetics‐modification are crucial for further improvement of open‐circuit voltage (Voc) and efficiency of Cu2ZnSn(S,Se)4 (CZTSSe) solar cells. Herein, a simple but effective cation substitution strategy is reported to promote the performance of CZTSSe devices by simultaneously modifying the absorber and heterojunction interface. This is achieved by introducing the organic silicon salt C8H20O4Si into CZTSSe precursor solution as a source of silicon to partially substitute Sn with Si. Systematic studies reveal that there are two mechanisms synergistically contributing to the increase of efficiency: 1) This strategy can passivate the undesired SnZn defect in CZTSSe absorber more efficiently, leading to at least one order of magnitude lower SnZn defect density and beneficial carrier transport properties; 2) After Si incorporation, the conduction band minimum of the CZTSSe is upshifted, thus enlarging the bandgap, which ultimately optimizes the energy level structure at the CdS/CZTSSe interface and reduces interfacial energy loss by decreasing the carrier transport barrier. Consequently, the CZTSSe device with 7% Si substitution delivers a satisfactory efficiency of 13.02% owing to an increase in Voc. It is hoped the Si substitution strategy reported here can provide inspiration for developing advanced CZTSSe devices with broad application prospects. [ABSTRACT FROM AUTHOR]

Ovarian cancer remains a significant health issue worldwide, often facing limitations in treatment due to side effects and drug resistance. Tumor cells typically undergo the "Warburg effect," preferring glycolysis, which leads to their rapid growth and survival. Metformin, a widely used diabetes medication, targets 5' adenosine monophosphate‐activated protein kinase (AMPK), reducing glycolysis and thereby slowing tumor growth. Additionally, forkhead box protein K2 (FOXK2), a transcription factor often found in excess in many tumors, promotes glycolysis and tumor development. Delivering metformin and FOXK2 siRNA directly to the tumor site in the body is challenging due to the metformin's poor water solubility and the fragile nature of siRNA. To address this, zirconium and 5,10,15,20‐tetra(4‐pyridyl)porphyrin nanoparticles loaded with FOXK2 siRNA, enveloped in cell membrane, co‐encapsulated with metformin in gelatin methacrylate microspheres (ZrTCP@siFOXK2@CM/Met@GelMA) hydrogel microspheres are developed for effective dual delivery. These microspheres facilitate targeted drug delivery, photothermal therapy with near‐infrared light, and interference with glucose metabolism. These results show that infrared light combined with metformin and FOXK2 siRNA successfully activates the AMPK pathway, reducing ovarian cancer growth. This method offers a promising new direction in treatment, utilizing the complex metabolic characteristics of ovarian cancer to achieve better results. [ABSTRACT FROM AUTHOR]

Thermally evaporated Se, including the molecules of Se2, Se5, Se6, Se7, and Se8 in the vapor at 550–600 °C, is widely used for the selenization of CZTSSe films. However, active small‐molecule Se2 tends to form large clusters of Se atoms at saturation vapor pressure, resulting in the large Se deficiency and poor crystallization of CZTSSe films. To regulate the time for Se to reach saturation vapor pressure and promote the role of active small‐molecule Se, the evaporation area of Se is controlled. Then the corresponding grain growth mechanism of CZTSSe films and device efficiency are systematically investigated. The results demonstrate that the appropriate evaporation area of Se can not only optimize the time for Se vapor to reach saturation, promote the rapid reaction crystallization between the precursor films and active Se2, but also inhibit the nucleation at the CZTSSe/Mo interface, thus making the CZTSSe films show a perfect top‐down grain growth mode. By preliminary optimization, when the evaporation area of Se is 245 mm2, a large‐grain spanning monolayer CZTSSe thin film is obtained; meanwhile, a device with a high efficiency of 12.39% is achieved. This study provides a new selenization strategy for improving the crystallinity of CZTSSe thin films. [ABSTRACT FROM AUTHOR]

Abundant intrinsic defects and defect clusters in Cu2ZnSn(S,Se)4 (CZTSSe) solar cells lead to severe nonradiative recombination and limited photoelectric performance. Therefore, developing effective method to suppress the detrimental defects is the key to achieve high‐efficiency solar cell. Herein, a convenient two‐step cooling strategy in selenization process is reported to suppress the CuZn and SnZn defects and defect clusters synergistically. The results show that rapid cooling during section from selenization temperature to turning temperature can inhibit the volatilization of Sn and restrain the corresponding Sn‐related defects, while slow cooling during the subsequent temperature section can reduce the degree of Cu‐Zn disorder. Benefitting from the synergistic effect of two‐step cooling, a significantly lowered concentration of SnZn and CuZn defect and their defect clusters [2CuZn+SnZn] in absorber is observed, meanwhile, a reduced band tailing effect and promoted carrier collection efficiency of the photovoltaic device is obtained. Finally, a device with improved open‐circuit voltage (Voc) of 505.5 mV and efficiency of 12.87% is achieved. This study demonstrates the impact of cooling process on defects controlling for the first time and provides a simple and effective new strategy for intrinsic defect control, which may be universal in other inorganic thin film solar cells. [ABSTRACT FROM AUTHOR]

The photovoltaic performance of the environmentally friendly Cu2ZnSn(S,Se)4 (CZTSSe) solar cells is lower than its predecessor Cu(In,Ga)Se2 solar cells. Severe carrier recombination at the CZTSSe/CdS interface is one major reason that results in a large open‐circuit voltage loss. Doping zinc into CdS is a feasible strategy to modifying the CdS buffer layer film, but the present methods are not satisfactory. In this study, novel zinc incorporation strategy is developed to deposit a gradient composition ternary ZnxCd1–xS buffer layer for optimizing the heterojunction interface. The application of gradient composition ZnxCd1–xS buffer layer constructs a gradient conduction band energy configuration in the CZTSSe/buffer layer interface, which highly reduces the interface recombination. The suppressed interface recombination contributes to the enhanced open circuit voltage and device performance. Consequently, the CZTSSe solar cell based on gradient composition ZnxCd1–xS buffer layers achieves champion efficiency of 12.35% with VOC of 504.81 mV, JSC of 36.90 mA cm−2, and FF of 66.28%. It is worth noting that flammable and the toxic hydrazine solvent are replaced by the safe and low‐toxic 2‐methoxyethanol, making it more promising for the future commercialization of CZTSSe solar cells. [ABSTRACT FROM AUTHOR]

Despite the tremendous progress in the efficiency of Cu2ZnSn(S,Se)4 (CZTSSe) photovoltaic devices, open‐circuit voltage (Voc) deficit, mainly related to the SnZn‐related defects in the absorber, still remains one of the key issues that hinders the cell performance. To overcome this hurdle, here a facile synergistic post‐deposition treatment (PDT) strategy in CZTSSe family via AgF‐PDT after LiF‐PDT in the photovoltaic absorber to suppress SnZn defects, and thus, to promote the Voc and power conversion efficiency (PCE), is reported. Furthermore, a mechanism for improving device efficiency of CZTSSe cell is also proposed. The in‐depth investigation results demonstrate that Li/Ag co‐doping reduces the band tailing characteristic, enlarges the depletion region width, and enhances the carrier transport and collection, resulting in a lower bulk and interface recombination. More importantly, Li/Ag co‐doping strategy provides an effective method for SnZn defect passivation, thereby prolonging minority carrier lifetime in the ensuing devices and leading to enhancement in device performance. Correspondingly, the resulting Li/Ag co‐doped device delivers a champion efficiency of 12.58% with an impressive Voc of 507 mV. This work explores an effective strategy to kill the SnZn‐related defects, thereby overcoming the problems associated with the Voc deficit and lower cell efficiency in Kesterite‐based photovoltaic devices. [ABSTRACT FROM AUTHOR]

The human hepatic organic ion transporting polypeptides OATP1B1 and ‐1B3 are uptake transporters that influence the disposition of several small molecule drugs and perpetrate certain adverse drug‐drug interactions. To predict these in vivo effects, in vitro systems are used to screen new drug entities as potential transporter substrates or inhibitors. To simplify such studies, we synthesized luminogenic derivatives of the OATP1B1 and ‐1B3 substrate D‐luciferin to test as probe substrates in a rapid, no‐wash optical approach for substrate and inhibitor identification and characterization. Each derivative is a pro‐luciferin containing a self‐immolating trimethyl lock quinone linker that is sensitive to intracellular reducing environments that cause the release of free luciferin in proportion to the amount of probe taken up by the transporter. A subsequent luciferin‐limited luciferase reaction produces light in proportion to transporter activity. We tested the derivatives in HEK293 cells that overexpress OATP1B1 or OATP1B3 by transient transfection or viral transduction. Derivatives were identified that showed OATP‐dependent uptake that was time and concentration dependent, saturable and sensitive to inhibition by known OATP1B1 and ‐1B3 substrates and inhibitors. These luminogenic transporter probes enabled an add‐only multi‐well plate protocol suitable for automation and high throughput screening. [ABSTRACT FROM AUTHOR]

Solution processing of Cu(In,Ga)Se2 (CIGS) absorber makes it cost‐competitive in the photovoltaic market. It is reported that copper‐poor ordered vacancy compound (OVC) is crucial for high performance CIGS solar cells. However, in solution process method, controllable formation of OVC is unavailable and limited research has been carried out. In this work, the controllable formation of the OVC phase on the CIGS surface is successful by controlling the selenization temperature and intentional variation of Cu/(In+Ga) stoichiometry in precursors for top layers and bulk layers deposition. The effects of OVC contents on the device performance are investigated. The CIGS thin film with OVC phase exhibits a lower valence band position. Meanwhile, the CIGS devices with optimized OVC content show decreased interface defects density and better carrier collection ability. The above advantages translate into a champion PCE of 16.39% for CIGS device with OVC phase, which is the champion performance among non‐hydrazine solution‐processed CIGS solar cells. The results demonstrate that the controllable formation of OVC phase approach should make a significant contribution to the efficiency promoting of solution processed CIGS solar cells. [ABSTRACT FROM AUTHOR]

ABSTRACT Energy Performance Contracting (EPC) is an important and effective energy conservation mechanism, under which an energy service company (ESCO) provides an energy-saving service to its client and shares the resulting energy cost savings. Using a game-theoretic model, we investigate the impacts of EPC on two competing manufacturers, of which one is more energy-efficient in production than the other. The less energy-efficient firm first proposes an energy-saving sharing contract to the more energy-efficient firm, who, if accepting the contract, acts as an ESCO that decides the energy-saving target and helps realize it for the client. Then the firms engage in Cournot competition by producing/selling substitutable products. By solving the equilibrium solutions, we show that under an EPC project, the total production quantity of both firms increases (so the market price of the product decreases) with the ESCO producing less while its client producing more, which also leads to a higher consumer surplus. Meanwhile, both manufactures are better off under EPC and would obtain strictly higher profits when the service cost rate is high. Nevertheless, EPC may not result in a better environmental performance in that the total energy consumption of both firms may be higher under EPC, which happens when the market size is small and the ESCO has not much energy-efficiency advantage over its client. We also study four extensions: When the energy saving service and production decisions are made separately, we find the more energy-efficient firm is worse off when implementing EPC; when the energy-saving sharing ratio is determined by the ESCO instead of the client, the ESCO extracts all the surplus derived from the EPC project while the total energy consumption of both firms is always reduced; when the energy-saving sharing ratio is determined via Nash bargaining, the main insights from the base model remain valid; finally, when the client sets the target of overall cost reduction, it extracts all the surplus derived from the EPC project. [ABSTRACT FROM AUTHOR]

Employing green and economic solvent-free synthesis route, hexagonal iron sulfide (Fe7S8) nanoflowers were successfully synthesized for the first time. In the experiment, ferric hexadecylxanthate was used as the precursor, and hexagonal iron sulfide (Fe7S8) nanoflowers were obtained by thermal decomposition of the precursor at 260°C without any additional solvent or inert gas protection. The as-prepared iron sulfide nanoflowers were characterized by means of X-ray diffraction (XRD), transmission electron microscopy (TEM), scanning electron microscopy (SEM) and energy dispersive spectrometry (EDS). The characterization results indicated that the nanoflowers had uniform size distribution with an average size of about 160 nm. The proposed strategy provides a possible general route for the synthesis of other metal chalcogenide nanostructures. [ABSTRACT FROM AUTHOR]

Assemble-to-order (ATO) is an important operational strategy for manufacturing firms to achieve quick response to customer orders while keeping low finished good inventories. This strategy has been successfully used not only by manufacturers (e.g., Dell, IBM) but also by retailers (e.g., Amazon.com). The evaluation of order-based performance is known to be an important but difficult task, and the existing literature has been mainly focused on stochastic comparison to obtain performance bounds. In this article, we develop an extremely simple Stein-Chen approximation as well as its error-bound for order-based fill rate for a multiproduct multicomponent ATO system with random leadtimes to replenish components. This approximation gives an expression for order-based fill rate in terms of component-based fill rates. The approximation has the property that the higher the component replenishment leadtime variability, the smaller the error bound. The result allows an operations manager to analyze the improvement in order-based fill rates when the base-stock level for any component changes. Numerical studies demonstrate that the approximation performs well, especially when the demand processes of different components are highly correlated; when the components have high base-stock levels; or when the component replenishment leadtimes have high variability. © 2012 Wiley Periodicals, Inc. Naval Research Logistics, 2012 [ABSTRACT FROM AUTHOR]

Objective To investigate the one-year prevalence of musculoskeletal symptoms and associated risk factors in a large sample of Chinese workers in various industrial settings. Methods A total of 5,338 (3,632 males and 1,706 females) workers from 13 companies participated in this study. Musculoskeletal symptoms in different body regions in the previous year and their risk factors were assessed by a self-reported questionnaire. Logistic regression analyses were performed to estimate the individual, work-related physical and psychosocial risk factors for the musculoskeletal symptoms. Results The most commonly affected body regions among the workers were lower back (59.7%), neck (48.6%), shoulders (38.8%), and wrists (33.5%). Female workers had greater prevalence of musculoskeletal symptoms in the neck, shoulders, and wrists than male workers. Results of multivariate analyses indicated that individual, work-related physical and psychosocial factors were associated with the musculoskeletal symptoms. Conclusion The results suggest that interventions aimed at reducing musculoskeletal symptoms in the Chinese working population should take into account multiple risk areas including individual, physical job characteristics and work-related psychosocial factors. Am. J. Ind. Med. 55:281-293, 2012. © 2011 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]

In spite of the clinical importance of prostate cancer (PCa) bone metastasis, the precise mechanisms for the directed migration of malignant cells remain unclear. In the present study, the expression of CXCR6 in human PCa and benign prostatic hyperplasia samples, and the expression of CXCL16 in human osseous tissues were determined by immunohistochemistry. It was found that the level of CXCR6 protein expression was elevated in human malignant prostate tumors, and CXCL16 was expressed positively by human osteocytes in vivo. The in vitro experiments further confirmed that the PCa cell lines PC3 and LNCap expressed CXCR6 at both the mRNA and protein levels, and exogenous CXCL16 has the potential to stimulate the invasion of PC3 and LNCap. To further elucidate the role of the CXCL16–CXCR6 axis in PCa progression, we compared the expression of CXCR6 and CXCR4 in human PCa tissues and the effects of CXCL16 and CXCL12 on the in vitro invasion of PC3 and LNCap cells. It was shown that CXCR6 and CXCR4 proteins were coexpressed and elevated in human PCa samples, and CXCL16 and CXCL12 promoted the invasion of PC3 and LNCap via their respective receptors. Furthermore, in contrast to CXCL12, which enhanced the activity of matrix metalloproteinase (MMP) 9 and MMP2 in PC3 and LNCap, CXCL16 ligation resulted in stronger MMP9 and MMP2 activity in LNCap but not in PC3. Our results suggest that besides CXCL12/CXCR4, CXCL16/CXCR6 might be another important factor involved in PCa bone metastasis. ( Cancer Sci 2008; 99: 1362–1369) [ABSTRACT FROM AUTHOR]

A back contact interface in a kesterite Cu2ZnSn(S,Se)4 (CZTSSe) photovoltaic device plays an important role in fabricating high quality semiconducting photoactive layers and improving carrier extraction efficiency. However, uncontrolled decomposition reactions between the CZTSSe absorber layer and Mo electrode result in high series resistance and recombination at the back interface. The insertion of high work function MoO3 as an interfacial layer is considered as a promising way to engineer the back contact. This highlights the importance of elucidating the chemistry and dynamics of MoO3 at the Mo/kesterite interface in the CZTSSe annealing process. Herein, A detailed investigation of the elemental diffusion and chemistry of the back contact with the MoO3 intermediate layer during selenization is carried out. The results demonstrate that the presence of the MoO3 interfacial layer largely suppresses the chemical reaction between Mo and CZTSSe in the annealing process, inducing high quality CZTSSe absorbing films with fewer voids and reducing the thickness of MoSe2 from 209 to 84 nm when the optimized thickness of MoO3 is 10 nm. This finally leads to the increase in device efficiency from 9.02% to 10.92%, and the best performance where an efficiency of 11.37% is achieved. [ABSTRACT FROM AUTHOR]

High‐crystalline‐quality absorbers with fewer defects are crucial for further improvement of open‐circuit voltage (VOC) and efficiency of Cu2ZnSn(S,Se)4 (CZTSSe) solar cells. However, the preparation of high‐quality CZTSSe absorbers remains challenging due to the uncontrollability of the selenization reaction and the complexity of the required selenization environment for film growth. Herein, a novel segmented control strategy for the selenization environment, specifically targeting the evaporation area of Se, to regulate the selenization reactions and improve the absorber quality is proposed. The large evaporation area of Se in the initial stage of the selenization provides a great evaporation and diffusion flux for Se, which facilitates rapid phase transition reactions and enables the attainment of a single‐layer thin film. The reduced evaporation area of Se in the later stage creates a soft‐selenization environment for grain growth, effectively suppressing the loss of Sn and promoting element homogenization. Consequently, the mitigation of Sn‐related deep‐level defects on the surface and in the bulk induced by element imbalance is simultaneously achieved. This leads to a significant improvement in nonradiative recombination suppression and carrier collection enhancement, thereby enhancing the VOC. As a result, the CZTSSe device delivers an impressive efficiency of 13.77% with a low VOC deficit. [ABSTRACT FROM AUTHOR]

The human hepatic organic ion transporting polypeptides OATP1B1 and ‐1B3 are uptake transporters that influence the disposition of several small molecule drugs and perpetrate certain adverse drug‐drug interactions. To predict these in vivo effects, in vitro systems are used to screen new drug entities as potential transporter substrates or inhibitors. To simplify such studies, we synthesized luminogenic derivatives of the OATP1B1 and ‐1B3 substrate D‐luciferin to test as probe substrates in a rapid, no‐wash optical approach for substrate and inhibitor identification and characterization. Each derivative is a pro‐luciferin containing a self‐immolating trimethyl lock quinone linker that is sensitive to intracellular reducing environments that cause the release of free luciferin in proportion to the amount of probe taken up by the transporter. A subsequent luciferin‐limited luciferase reaction produces light in proportion to transporter activity. We tested the derivatives in HEK293 cells that overexpress OATP1B1 or OATP1B3 by transient transfection or viral transduction. Derivatives were identified that showed OATP‐dependent uptake that was time and concentration dependent, saturable and sensitive to inhibition by known OATP1B1 and ‐1B3 substrates and inhibitors. These luminogenic transporter probes enabled an add‐only multi‐well plate protocol suitable for automation and high throughput screening. [ABSTRACT FROM AUTHOR]

Background: Lupus erythematosus (LE) is a spectrum of autoimmune diseases. Due to the complexity of cutaneous LE (CLE), clinical skin image-based artificial intelligence is still experiencing difficulties in distinguishing subtypes of LE., Objectives: We aim to develop a multimodal deep learning system (MMDLS) for human-AI collaboration in diagnosis of LE subtypes., Methods: This is a multi-centre study based on 25 institutions across China to assist in diagnosis of LE subtypes, other eight similar skin diseases and healthy subjects. In total, 446 cases with 800 clinical skin images, 3786 multicolor-immunohistochemistry (multi-IHC) images and clinical data were collected, and EfficientNet-B3 and ResNet-18 were utilized in this study., Results: In the multi-classification task, the overall performance of MMDLS on 13 skin conditions is much higher than single or dual modals (Sen = 0.8288, Spe = 0.9852, Pre = 0.8518, AUC = 0.9844). Further, the MMDLS-based diagnostic-support help improves the accuracy of dermatologists from 66.88% ± 6.94% to 81.25% ± 4.23% (p = 0.0004)., Conclusions: These results highlight the benefit of human-MMDLS collaborated framework in telemedicine by assisting dermatologists and rheumatologists in the differential diagnosis of LE subtypes and similar skin diseases., (© 2024 European Academy of Dermatology and Venereology.)