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Objectives Bloodstream infection (BSI) is one of the major causes of death in pediatric tumor patients. Blood samples are relatively easy to obtain and thus provide a ready source of infection-related biological markers for the prompt evaluation of infection risk. Methods A total of 259 pediatric tumor patients were included from May 2019 to March 2022. Patients were divided into BSI group (n=70) and control group (n=189). Clinical and biological data were collected using electronic medical records. Differences in biological markers between BSI group and control group and differences before and during infection in BSI group were analyzed. Results The infected group showed higher levels of procalcitonin (PCT) and hypersensitive C-reactive-protein (hsCRP), and lower prealbumin (PA) than the uninfected group. Area under the receiver-operating curve (ROC) curves (AUC) of PCT, hsCRP and NLR (absolute neutrophil count to the absolute lymphocyte count) were 0.756, 0.617 and 0.612. The AUC of other biomarkers was ≤0.6. In addition, PCT, hsCRP, NLR and fibrinogen (Fg) were significantly increased during infection, while PA and lymphocyte (LYM) were significantly decreased. Antibiotic resistant of Gram-positive bacteria to CHL, SXT, OXA and PEN was lower than that of Coagulase-negative Staphylococcus. Resistant of Gram-positive bacteria to CHL was lower, while to SXT was higher than that of Gram-negative bacteria. Conclusions This study explored the utility of biomarkers to assist in diagnosis and found that the PCT had the greatest predictive value for infection in pediatric tumor patients with BSI. Additionally, the PCT, hsCRP, NLR, PA, LYM and Fg were changed by BSI.

The Tibetan Plateau and its surroundings have recently experienced several catastrophic glacier-related disasters. It is of great scientific and practical significance to establish ground-based early warning systems (EWS) to understand the processes and mechanisms of glacial disasters and warn against potential threats to downstream settlements and infrastructure. However, there are few sophisticated EWSs on the Tibetan Plateau. With the support of the Second Tibetan Plateau Scientific Expedition and Research Program, an EWS was developed and implemented in the Sedongpu Valley, southeastern Tibetan Plateau, where repeated river blockages have occurred due to ice/rock collapse debris flow. The EWS collected datasets of optical/thermal videos/photos, geophone waveforms, water levels, and meteorological variables in this sparsely populated zone. It has successfully warned against three ice-rock collapse-debris flow - river blockage chain events and seven small-scale ice-rock collapse-debris flow events. Meanwhile, it was found that the low-cost geophone can effectively indicate the occurrence and magnitude of ice/rock collapses by local thresholds, and water level observation is an efficient way to warn of river blockages. Our observations showed that several factors, such as the volume and location of the collapses and the percentage of ice content involved, influence the velocities of debris flows and the magnitude of river blockages. There are still two possible glaciers in the study area that are at risk of ice collapse. It is worth monitoring their dynamic changes using high-resolution satellite data and the ground-based EWS to safeguard the surrounding hydrological projects and infrastructure in this transboundary region.

On 22 March 2021, an approximately 50 Mm3 ice-rock avalanche occurred from 6500 m a.s.l. in the Sedongpu basin, southeastern Tibet. The avalanche transformed into a highly mobile mass flow which temporarily blocked the Yarlung Tsangpo river. The avalanche flow lasted ∼ 5 min and produced substantial geomorphological reworking. This event, and previous ones from the basin, occurred concurrently with, or shortly after, positive seasonal air temperature anomalies. The occurrence of future large mass flows from the basin cannot be ruled out, and their impacts must be carefully considered given implications for sustainable hydropower and associated socioeconomic development in the region.

Ultraviolet (UV) sensitive photodetectors (PDs) are highly desired for surface defect detection applications. Here, an ultra-stable and high-performance UV PDs with a TiO2/MAPbCl3/PTAA pin structure is achieved by vapor-phase anion...

Debris-covered glaciers are a common feature of the mountain cryosphere in the southeastern Tibetan Plateau. A better understanding of these glaciers change is necessary to reduce the uncertainties of the regional water resource variability, and to anticipate potential cryospheric risks. In this study, we quantify seasonal thinning (dh) and surface mass balance (SMB) patterns of two neighboring debris-covered glaciers (23 K Glacier and 24 K Glacier) in the southeastern Tibetan Plateau with repeated unpiloted aerial vehicle (UAV) surveys and in-situ measurements. We observe that the dh pattern of 23 K Glacier is distinct from that of 24 K Glacier, despite their proximity. The dh magnitude of the 23 K Glacier is ~1.4–3.0 times greater than that of the 24 K Glacier at all periods, which is mainly driven by the stronger dynamic state of 24 K Glacier. The contrasted behaviour between the two glaciers is also valid in the early twenty-first century. In contrast, the SMB patterns of the two glaciers are generally in agreement at different periods. The debris thickness distribution correlates with the SMB spatial distribution for both glaciers, while the supraglacial ice cliffs and ponds area density distribution is not correlated with SMB spatial distribution. This high-resolution comparison study of two neighboring glaciers confirms the significance of both glacier dynamic and debris thickness in controlling the thinning and melt for the different type debris-covered glaciers of the southeastern Tibetan Plateau in the context of climate change.

Ice cliff distribution plays a major role in determining the melt of debris-covered glaciers but its controls are largely unknown. We assembled a dataset of 37537 ice cliffs and determined their characteristics across 86 debris-covered glaciers within High Mountain Asia (HMA). We complemented this dataset with the analysis of 202 cliff formation events from multi-temporal UAV observations for a subset of glaciers. We find that 38.9% of the cliffs are stream-influenced, 19.5% pond-influenced and 19.7% are crevasses. Surface velocity is the main predictor of cliff distribution at both local and glacier scale, indicating its dependence on the dynamic state and hence evolution stage of debris-covered glacier tongues. Supraglacial ponds contribute to maintaining cliffs in areas of thicker debris, but this is only possible if water accumulates at the surface. Overall, total cliff density decreases exponentially with debris thickness as soon as debris gets thicker than 10 cm.

Background: Primary osteoporosis (POP) is one of the most common orthopedic diseases with a high risk of fracture. Effective treatment of POP is of great significance to reduce the rate of disability and improve the quality of life. Bushen qianggu (BSQG) is a classical method of TCM in treating POP. However, there is no systematic review related to BSQG for POP. The purpose of this study is to provide a comprehensive and reliable evaluation of the clinical evidence of BSQG in the treatment of POP. Methods and analysis: Relevant randomized controlled trial literature evaluating the effect of BSQG on patients with POP will be obtained by searching the PubMed, Embase, MEDLINE, Cochrane Library Central Register of Controlled Trials, China national knowledge infrastructure database, Wan fang database, Chongqing VIP information, and SinoMed from their inception to May 2020. Two researchers will select and evaluate qualified studies independently. The bone mineral density value and the incidence of fractures will be accepted as the primary outcomes. The meta-analyses will be performed by using the RevMan 5.3. Results: This study will provide a comprehensive evaluation of the efficacy and safety of BSQG method for patients with POP. Conclusion: The conclusion of our systematic review will provide evidence to judge whether BSQG is an effective intervention for patients with POP. Trial registration number: 10.17605/OSF.IO/ZMX3W.

Researchers have attempted to create wide-angle field-of-view (FOV) cameras inspired by the structure of the eyes of animals, including fisheye and compound eye cameras. However, realizing wide-angle FOV cameras simultaneously exhibiting low distortion and high spatial resolution remains a significant challenge. In this study, a novel wide-angle FOV camera is developed by combining a single large-area flexible perovskite photodetector (FP-PD) using computational technology. With this camera, the proposed single-photodetector imaging technique can obtain high-spatial-resolution images using only a single detector, and the large-area FP-PD can be bent further to collect light from a wide-angle FOV. The proposed camera demonstrates remarkable features of an extraordinarily tunable wide FOV (greater than 150°), high spatial resolution of 256 × 256 pixels, and low distortion. It is believed that the proposed compatible and extensible camera prototype will promote the development of high-performance versatile FOV cameras.

Two-dimensional (2D) magnetic materials are essential for the development of the next-generation spintronic technologies. Recently, layered van der Waals (vdW) compound MnBi2Te4 (MBT) has attracted great interest, and its 2D structure has been reported to host coexisting magnetism and topology. Here, we design several conceptual nanodevices based on MBT monolayer (MBT-ML) and reveal their spin-dependent transport properties by means of the first-principles calculations. The pn-junction diodes and sub-3-nm pin-junction field-effect transistors (FETs) show a strong rectifying effect and a spin filtering effect, with an ideality factor n close to 1 even at a reasonably high temperature. In addition, the pip- and nin-junction FETs give an interesting negative differential resistive (NDR) effect. The gate voltages can tune currents through these FETs in a large range. Furthermore, the MBT-ML has a strong response to light. Our results uncover the multifunctional nature of MBT-ML, pave the road for its applications in diverse next-generation semiconductor spin electric devices., Comment: 6 pages, 6 figures

Corrosion of metals in atmospheric environments is a worldwide problem in industry and daily life. Traditional anticorrosion methods including sacrificial anodes or protective coatings have performance limitations. Here, we report atomically thin, polycrystalline few-layer graphene (FLG) grown by chemical vapor deposition as a long-term protective coating film for copper (Cu). A six-year old, FLG-protected Cu is visually shiny and detailed material characterizations capture no sign of oxidation. The success of the durable anticorrosion film depends on the misalignment of grain boundaries between adjacent graphene layers. Theoretical calculations further found that corrosive molecules always encounter extremely high energy barrier when diffusing through the FLG layers. Therefore, the FLG is able to prevent the corrosive molecules from reaching the underlying Cu surface. This work highlights the interesting structures of polycrystalline FLG and sheds insight into the atomically thin coatings for various applications.

Lead-free perovskites exhibit low toxicity and have been investigated as new active materials for photoconversion applications. Among them, Cs3Bi2I9 perovskites have received extensive attention due to their eco-friendliness, excellent stability and high photosensitivity. Herein, the optical and electronic bandgap of Cs3Bi2I9 thin films are determined to be 2.19 eV and 2.55 eV, providing insights into strong excitonic photodetection materials. Furthermore, we introduce an ultrathin Al2O3 layer into the interface of Cs3Bi2I9 perovskite PDs using the atomic layer deposition (ALD). The ON/OFF ratio can be significantly improved by 20-fold using an Al2O3 layer with an optimal thickness of 1.5 nm due to the interfacial-tunneling-effect. Moreover, the unsealed Cs3Bi2I9 perovskite PDs exhibit excellent stability, and can retain 90% of their original performance after 30 days under ambient conditions (25 °C, RH = 60%). Furthermore, the potential application in diffuse reflection imaging has been explored based on Cs3Bi2I9 perovskite PDs without encapsulation, confirming a high-resolution and high-contrast imaging demonstration.

Ice cliffs are important contributors to the mass balance of debris-covered glaciers, especially in High Mountain Asia where they can account for one sixth of the melt of debris-covered glacier tongues, despite covering less than 10% of their area. These features have been shown to evolve, appear and disappear rapidly from year to year, with high variability in relative area and number. It has been hypothesized that ice cliffs expand and melt more rapidly during the monsoon (June-September), but there are very few observations during this period. Here, we use arrays of time-lapse cameras to reconstruct the geometry of four ice cliffs at a weekly timestep over a period of four to six months at two monsoon-affected sites: Langtang Glacier in Nepal, and 24K Glacier in South-Eastern Tibet. We use Structure-from-Motion photogrammetry to derive point clouds and Digital Elevation Models (DEMs) of the glacier surface, using the stable background terrain to constrain viewing geometries and DEM errors. This technique (time-lapse photogrammetry) enables a high accuracy, quantitative measurement of processes occurring at the cliff-scale (elevation uncertainties stay below 30cm at a distance of 300m from the cameras) and at high temporal resolution over the monsoon season, when dense cloud cover and intense precipitation prevent field- or satellite-based observations. We derive the melt patterns of these cliffs from the differencing of the weekly DEMs by accounting for glacier flow. We compare the observed melt patterns with the modeled energy-balance at the cliff surface and use these observations to quantify the influence of debris slumping and redistribution, as well as supraglacial ponds and streams on the melt patterns of these cliffs. The results highlight the seasonal variations of cliff melt, which occurs at up to 8 cm/day during the monsoon, twice as high as observed in the pre- and post-monsoon period. Our energy-balance results indicate that melt rates are driven by incoming long- and shortwave radiation, and are thus highly dependent on the cliff slope and aspect, as substantiated by our photogrammetric measurements. The observations also demonstrate the competitive influence of debris, which progressively reburies the cliff by accumulating at its surface, and supraglacial streams and ponds, which maintain the cliff slope by preventing debris accumulation at the base. These results will help in understanding the surface evolution of debris-covered glaciers and enable a better representation of ice cliff melt and evolution in glacio-hydrological models.

Catastrophic mass flows originating from the mountain cryosphere can cause widespread loss of life, destruction of property, and significant geomorphological reworking along flow paths. Based on in-situ field investigations, high-resolution satellite imagery, digital elevation models (DEMs), seismic records, and meteorological data, we present the process reconstruction, triggering mechanism, and downstream implications of a 50 Mm3 ice-rock avalanche and mass flow that originated from 6500 m asl of the Sedongpu basin in southeastern Tibet on 22 March 2021.The avalanche transformed into a highly mobile mass flow which temporarily blocked the Yarlung Tsangpo river. The avalanche flow lasted ~5 minutes and produced substantial geomorphological reworking. This event, and previous ones from the basin (a total of ~50 Mm3 on October 2017 and into 2018 occurring close to the 2021 ice-rock avalanche source region, and the detachment of the low-angle tongue of Sedongpu Glacier in two separate events with a total of ~130 Mm3 on 17/18 October and 29 October 2018), occurred concurrently with, or shortly after periods characterized by record positive air temperature anomalies, which may have contributed to instability of the mountain cryosphere. The occurrence of future large mass flows from the basin under anthropogenic warming cannot be ruled out, and their likelihood and impacts must be carefully considered given potential risks to life and implications for sustainable hydropower and associated socioeconomic development along the Brahmaputra.

Dual-color or multispectral imaging based on conventional optical imaging techniques is suffering from the bottleneck of complex manufacturing and time consumption caused by multiple imaging. Herein, we develop a dual-color computational imaging system combining a vertically stacked dual-channel dual-band perovskite photodetectors (PDs) and the advanced Fourier imaging algorithm. Significantly, our imaging system bypasses the complex fabrication process of high-density dual-band PD arrays and is enabled to capture two high-resolution spectral images at the same time. Based on the experiments and simulations, we confirm that the spectral overlap of dual-band PDs will cause detrimental effect for color identification, and optimizing the bandwidth spectrum is beneficial for achieving much better spectral imaging. Moreover, we have further improved the imaging quality by increasing the sampling rate and suppressing current fluctuations. We suggest that these results provide important interesting insights for the development of advanced imaging systems, including IR imaging, THz imaging, multispectral/hyperspectral imaging, etc.

A detailed understanding of the anatomical and molecular architectures of cells and their system-wide connectivity is essential for interrogating system function and dysfunction. Extensive efforts have been made toward characterizing cells through various approaches, and have established invaluable databases yielding new insights. However, we still lack technologies for mapping the combined multi-scale anatomical and molecular details of individual cells in the human organ-scale system. To address this challenge, we developed a fully integrated technology platform for simultaneously extracting spatial, molecular, morphological, and connectivity information of individual cells from the same human brain at single-fiber resolution. We accomplished this by seamlessly integrating new chemical, mechanical, and computational tools to enable 3D multi-scale proteomic reconstruction of human organ tissues. We developed a novel microtome, termed MEGAtome, that enables ultra-precision slicing of whole-mount intact human brain hemispheres and large arrays of organs from other species with no loss of intra- and inter-slice cellular connectivity. To preserve structural and molecular information within intact human brain slabs and to enable multiplexed multiscale imaging, we developed a tissue-gel technology, termed mELAST, that transforms human brain tissues into an elastic and reversibly expandable tissue-hydrogel. To reconstruct the 3D connectivity of axonal networks across multiple brain slabs, we developed a computational pipeline termed UNSLICE. Using the technology platform, we analyzed Alzheimer’s disease (AD) pathology at multiple scales from overall cytoarchitecture to individual synapses. Finally, we demonstrated the feasibility of scalable neural connectivity mapping in human brain, establishing a path for probing brain connectivity and its alterations in diseases.One-Sentence SummaryWe developed an integrated scalable platform for highly multiplexed multi-scale phenotyping and connectivity mapping in the same human brain tissue, which includes novel tissue processing, labeling, imaging, and computational reconstruction technologies.

Recently, the newly booming metal halide perovskites have attracted extensive attention worldwide due to their outstanding optoelectronic performance, and are expected to be ideal candidates for photodetectors (PDs). However, there is still lack of perovskite PDs-based imaging devices coming into commercialization stage, due to some practical reasons including toxicity brought by lead-based perovskites and the large light current fluctuations. In this paper, for the first time we fabricate a lead-free Cs3Bi2Br9 perovskite PD, and build a prototype of this perovskite PD-based imaging system with diffuse reflection imaging mode. Moreover, we propose a new parameter F related to light current fluctuation to evaluate imaging performance of a PD especially for weak diffuse light condition, and prove its usability by comparison of unoptimized lead-free Cs3Bi2Br9 perovskite PD and atomic layer deposition (ALD) optimized Cs3Bi2Br9 PD. ALD-optimization can improve the quality of perovskite film and suppress the dark current and current fluctuation. Finally, we obtain satisfactory diffuse reflection images of 2D and 3D objects with wide dynamic range. Therefore, the ALD-optimized Cs3Bi2Br9 PD has addressed two major concerns about perovskite PDs-based imaging devices, that may extend application of perovskite materials and improve imaging quality.

Interface interactions between perovskite materials and substrates are of great significance for the development of high-quality perovskite materials. Herein, we have successfully prepared Cs2AgBiB...

Melt from supraglacial ice cliffs is an important contributor to the mass loss of debris-covered glaciers. However, ice cliff contribution is difficult to quantify as they are highly dynamic features, and the paucity of observations of melt rates and their variability leads to large modelling uncertainties. We quantify monsoon season melt and 3D evolution of four ice cliffs over two debris-covered glaciers in High Mountain Asia (Langtang Glacier, Nepal, and 24K Glacier, China) at very high resolution using terrestrial photogrammetry applied to imagery captured from time-lapse cameras installed on lateral moraines. We derive weekly flow-corrected digital elevation models (DEMs) of the glacier surface with a maximum vertical bias of ±0.2 m for Langtang Glacier and ±0.05 m for 24K Glacier and use change detection to determine distributed melt rates at the surfaces of the ice cliffs throughout the study period. We compare the measured melt patterns with those derived from a 3D energy balance model to derive the contribution of the main energy fluxes. We find that ice cliff melt varies considerably throughout the melt season, with maximum melt rates of 5 to 8 cm d−1, and their average melt rates are 11–14 (Langtang) and 4.5 (24K) times higher than the surrounding debris-covered ice. Our results highlight the influence of redistributed supraglacial debris on cliff melt. At both sites, ice cliff albedo is influenced by the presence of thin debris at the ice cliff surface, which is largely controlled on 24K Glacier by liquid precipitation events that wash away this debris. Slightly thicker or patchy debris reduces melt by 1–3 cm d−1 at all sites. Ultimately, our observations show a strong spatio-temporal variability in cliff area at each site, which is controlled by supraglacial streams and ponds and englacial cavities that promote debris slope destabilisation and the lateral expansion of the cliffs. These findings highlight the need to better represent processes of debris redistribution in ice cliff models, to in turn improve estimates of ice cliff contribution to glacier melt and the long-term geomorphological evolution of debris-covered glacier surfaces., The Cryosphere, 16 (11), ISSN:1994-0416, ISSN:1994-0424

Intrinsic polarization-sensitive photodetectors (IPPDs) have attracted considerable attention in recent years due to their simplicity in configuration, making them ideal candidates for compact and integrated polarization-sensitive sensing and imaging systems. Photoactive films with intrinsic optical anisotropy are necessary for IPPDs. This study reports an achievement of photoactive films based on all-polymer heterojunction films with in-plane optical anisotropy using a simple bottom-up self-assembly method. Both the donor (TQ1) and acceptor (N2200) polymers have the same spatial orientation with distinct anisotropy, approaching a dichroic ratio (DR) of 8. Polarization-sensitive light absorption is due to the uniaxially oriented polymer chains, which are dominated by lamellar packing with edge-on orientation. For IPPDs based on this anisotropic all-polymer heterojunction film, a photocurrent anisotropy was found with a polarized photocurrent ratio of 2.6. The detectivity of these IPPDs was found to be 1.9 × 1011 Jones (@ ∼600 nm, 0 V bias). Our work shows that oriented polymer donor–acceptor films fabricated using bottom-up self-assembly have great potential in applications, such as polarization detection.

Bi-based inorganic perovskites have attracted great attention in optoelectronics, as they feature similar photoelectric properties but have high stability and lead-free merits. Unfortunately, due to the high exciton binding energy and small Bohr radius, their photodetection performance still largely lags behind that of Pb-based counterparts. Herein, using a vapor-phase chloride ion-substitution strategy, Cs3Bi2Br9 photodetectors (PDs) with gradient energy band alignment were delicately modulated, contributing to a high carrier separation/collection efficiency. The optimized Bi-based perovskite ACCT (Al2O3/Cs3Bi2Br9/Cs3Bi2ClxBr9-x/TiO2) PDs exhibit outstanding performance, the ON/OFF ratio and linear dynamic range (LDR) are significantly improved by 20 and 2.6 times, respectively. Significantly, we further demonstrate the high-SNR (signal-to-noise ratio) UV imaging based on the optimized device, which shows 21.887 dB higher than that of the pristine device. Finally, the vapor-phase anion-exchange modified perovskite PDs show long-term stability and high UV resistance. Vapor-phase ion-substitution is a promising approach for the synergistic effect of matched energy band alignment and interface passivation, which can be applied to other perovskite-based optoelectronic devices.

Background CKS1 is highly expressed in colon cancer tissues, and is essential for cancer cell proliferation. The downstream molecular mechanism of CKS1 has been fully studied, but the upstream regulatory mechanism of it is still unclear. Earlier research found that PADI3 plays its anti-tumor roles via suppress cell proliferation, in this study, we found that the expression pattern of PADI3 and CKS1 are negatively correlated in colon cancer tissues, and overexpression of PADI3 can partly reverse CKS1 induced cancer cell proliferation. However, the regulatory mechanism of PADI3 and CKS1 in the tumorigenesis of colon cancer is still unclear and need to do further research. Methods Western blot and real-time PCR were used to detect the expression levels of genes. CCK-8 and colony formation assays were used to examine cell proliferation and colony formation ability. Overexpression and rescue experiments were used to study the molecular mechanism of CKS1 in colon cancer cells, BALB/c nude mice were used to study the function of CKS1 in vivo. Results CKS1 is highly expressed in colon cancer tissues, and the overexpression of CKS1 promotes cell proliferation and colony formation in both HCT116 (originating from primary colon cancer) and SW620 (originating from metastatic tumor nodules of colon cancer) cells. CKS1-expressing HCT116 cells produced larger tumors than the control cells. The expression pattern of PADI3 and CKS1 are negatively correlation in clinical samples of colon cancer, further study indicates that PADI3 can significantly decrease Hsp90 and CKS1 expression, and Hsp90 is essential for PADI3 to downregulate CKS1expression in colon cancer cells. Conclusions PADI3 exerts its antitumor activity by inhibiting Hsp90 and CKS1 expression, and Hsp90 is essential for PADI3 to suppress CKS1 expression.

Cuprite, nominally cuprous oxide (Cu2O) but more correctly Cu2–xO, is widely used in optoelectronic applications because of its natural p-type, nontoxicity, and abundant availability. However, the ...

Kesterite Cu2ZnSn(S,Se)4 (CZTSSe) thin film is a promising material for optoelectronic devices. In this work, we fabricate Mo/CZTSSe/CdS/ZnO/ITO (ITO, indium tin oxide) heterojunction photodetectors with favorable self-powered characteristics. The photodetector exhibits exceptional high-frequency photoresponse performance whose -3 dB bandwidth and rise/decay time have reached 1 MHz and 240/340 ns, respectively. For further improvement, ultrathin Al2O3 layer prepared via atomic layer deposition (ALD) process is introduced at the Mo/CZTSSe interface. The influence of ALD-Al2O3 layer thickness and its role on the photoresponse performance are investigated in detail. The interfacial layer proved to serve as a protective layer preventing selenization of Mo electrode, resulting in the reduction of MoSe2 transition layer and the decrease of series resistance of the device. Accordingly, the -3 dB bandwidth is remarkably extended to 3.5 MHz while the rise/decay time is dramatically improved to 60/77 ns with 16 cycles of ALD-Al2O3 layer, which is 4-5 orders of magnitude faster than the other reported CZTSSe photodetectors. Simultaneously, it is revealed that the ALD-Al2O3 interfacial layer acts as an electron blocking layer which leads to the effective suppression of carrier recombination at the rear surface. Consequently, the responsivity and detectivity are enhanced in the entire range while the maximum values are up to 0.39 AW-1 and 2.04 × 1011 Jones with 8 cycles of ALD-Al2O3, respectively. Finally, the CZTSSe photodetector is successfully integrated into a visible light communication system and obtains a satisfying transfer rate of 2 Mbps. These results indicate the satisfying performance of CZTSSe-based thin film photodetectors with great potential applications for communication.

The Cu(In,Ga)Se2 (CIGS) thin film has been commercialized as solar cells with great success, but its application for photodetectors still faces some practical challenges, including low detectivity ...

Molybdenum oxides have emerged as an important entity for optoelectronics due to their wide band gap and carrier-selective transportation property. However, there is little progress in the development of high-performance molybdenum oxide based photodetectors. Herein, a fast response and high detectivity (∼1.27 × 1013 Jones) photodetector based on the asymmetric heterojunction of MoO3−x/Si with a nanoporous pyramid array (NPPA) Si structure was reported. The device shows a broad linear dynamic range (LDR) over 116.6 dB and bandwidth over 50 kHz. Furthermore, the temperature-dependence of photoresponse was systematically investigated to probe the carrier transportation within the heterojunction. A model is proposed in which carrier diffusion dominates the photoresponse performance. Finally, the temperature-resistant NPPA based heterojunction photodetector is successfully integrated into a visible light communication system and its application as an optical signal receiver for transmitting texts is demonstrated. These findings suggest that our transition metal oxide based asymmetric heterojunction photodetectors have great application potential in optical communication.

Glaciers are key components of the water towers of Asia and as such are relied upon by large downstream communities for domestic, agricultural and industrial uses. They have experienced considerable shrinking over the last decades, with some of the highest rates of mass loss observed in the south-eastern part of the Tibetan Plateau, where mass loss is also accelerating. Despite these rapid changes, Tibetan glaciers’ changing role in catchment hydrology remains largely unknown. Parlung No.4 Glacier is considered as a benchmark glacier in this region, since its meteorology, surface energy fluxes and mass-balance have been examined since 2006. It is a maritime glacier with a spring (April-May) accumulation regime , which is followed by a period of ablation during the Indian Summer Monsoon (typically June-September). Here, we conduct a glacio-hydrological study over a period of five decades (1978-2018) using a fully distributed model for glacier mass balance and runoff simulation (TOPKAPI-ETH). We force the model with ERA5-Land and China Meteorological Forcing Dataset (CMFD) climate reanalysis downscaled to a local weather station to reconstruct meteorological time series at an hourly resolution. TOPKAPI-ETH is calibrated and validated with automatic weather station data, discharge measurements, geodetic mass balance, stake measurements and snow cover data from MODIS. We find a very clear acceleration in mass loss from 2000 onwards, which is mostly explained by an increase in temperature. This influence however was initially compensated by an increase in precipitation until the 2000’s, which attenuated the negative trend. Our results also indicate that the increase in the liquid-solid precipitation ratio has reduced the amount of seasonal accumulation, exacerbating annual mass loss. We demonstrate that the southern westerlies and the associated spring precipitation have as much influence on the glacier mass balance and catchment discharge as the Indian Summer Monsoon, by controlling seasonal snowpack development, which simultaneously provides mass to the glacier and protects it from melting in the early stage of the monsoon.