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Inorganic semiconductors typically have limited p-type behavior due to the scarcity of holes and the localized valence band maximum, hindering the progress of complementary devices and circuits. In this work, we propose an inorganic blending strategy to activate the hole-transporting character in an inorganic semiconductor compound, namely tellurium-selenium-oxygen (TeSeO). By rationally combining intrinsic p-type semimetal, semiconductor, and wide-bandgap semiconductor into a single compound, the TeSeO system displays tunable bandgaps ranging from 0.7 to 2.2 eV. Wafer-scale ultrathin TeSeO films, which can be deposited at room temperature, display high hole field-effect mobility of 48.5 cm2/(Vs) and robust hole transport properties, facilitated by Te-Te (Se) portions and O-Te-O portions, respectively. The nanosphere lithography process is employed to create nanopatterned honeycomb TeSeO broadband photodetectors, demonstrating a high responsibility of 603 A/W, an ultrafast response of 5 μs, and superior mechanical flexibility. The p-type TeSeO system is highly adaptable, scalable, and reliable, which can address emerging technological needs that current semiconductor solutions may not fulfill. The authors report an inorganic tellurium-selenium-oxygen (TeSeO) alloyed semiconductor for high-mobility p-channel transistors and broadband photodetectors, through the scalable thermal evaporation method combined with post-oxygen implantation. [ABSTRACT FROM AUTHOR]

Growing high-quality core-shell heterostructure nanowires is still challenging due to the lattice mismatch issue at the radial interface. Herein, a versatile strategy is exploited for the lattice-mismatch-free construction of III-V/chalcogenide core-shell heterostructure nanowires by simply utilizing the surfactant and amorphous natures of chalcogenide semiconductors. Specifically, a variety of III-V/chalcogenide core-shell heterostructure nanowires are successfully constructed with controlled shell thicknesses, compositions, and smooth surfaces. Due to the conformal properties of obtained heterostructure nanowires, the wavelength-dependent bi-directional photoresponse and visible light-assisted infrared photodetection are realized in the type-I GaSb/GeS core-shell heterostructure nanowires. Also, the enhanced infrared photodetection is found in the type-II InGaAs/GeS core-shell heterostructure nanowires compared with the pristine InGaAs nanowires, in which both responsivity and detectivity are improved by more than 2 orders of magnitude. Evidently, this work paves the way for the lattice-mismatch-free construction of core-shell heterostructure nanowires by chemical vapor deposition for next-generation high-performance nanowire optoelectronics. A versatility growth strategy is developed for the lattice-mismatch-free construction of core-shell heterostructure NWs by adopting the promising III-V semiconductors and amorphous chalcogenide semiconductors using simple chemical vapor deposition. [ABSTRACT FROM AUTHOR]

The purpose of this study is to test the feasibility for deep CNN–based artificial intelligence methods for automatic classification of the mass margin and shape, while radiomic feature–based machine learning methods were also implemented in this study as baseline and for comparison study. In this retrospective study, 596 patients with breast mass that underwent mammography from 4 hospitals were enrolled from January 2012 to October 2019. Margin and shape of each mass were annotated according to BI-RADS by 2 experienced radiologists. Deep CNN–based AI was implemented for the classification task based on Resnet50. Balanced sampler and CBAM were also used to improve the performance of the Deep CNNs. As comparison, image texture features were extracted and then dimensionality reduction methods (such as PCA, ICA) and classical classifiers (such as SVM, DT, KNN) were used for classification task. Based on Python programming software, accuracy (ACC) was used to evaluate the performance of the model, and the model with the highest ACC value was selected. Deep CNN based on Resnet50 with balanced sampler and CBAM achieved the best performance for both margin and shape classification, with ACC of 0.838 and 0.874, respectively. For the radiomics-based machine learning, the best performance for margin was achieved as 0.676 by the combination of FA + RF, while the best performance for shape was 0.802 by the combination of PCA + MLP. The feasibility for automatic classification with coarse labeling of the mass shape and margin was testified with the deep CNN–based AI methods, while radiomic feature–based machine learning methods achieved inferior classification results. [ABSTRACT FROM AUTHOR]

Chemical bonds, including covalent and ionic bonds, endow semiconductors with stable electronic configurations but also impose constraints on their synthesis and lattice-mismatched heteroepitaxy. Here, the unique multi-scale van der Waals (vdWs) interactions are explored in one-dimensional tellurium (Te) systems to overcome these restrictions, enabled by the vdWs bonds between Te atomic chains and the spontaneous misfit relaxation at quasi-vdWs interfaces. Wafer-scale Te vdWs nanomeshes composed of self-welding Te nanowires are laterally vapor grown on arbitrary surfaces at a low temperature of 100 °C, bringing greater integration freedoms for enhanced device functionality and broad applicability. The prepared Te vdWs nanomeshes can be patterned at the microscale and exhibit high field-effect hole mobility of 145 cm2/Vs, ultrafast photoresponse below 3 μs in paper-based infrared photodetectors, as well as controllable electronic structure in mixed-dimensional heterojunctions. All these device metrics of Te vdWs nanomesh electronics are promising to meet emerging technological demands. The limited scalability of 1D semiconductors has restricted their large-area optoelectronic applications so far. Here, the authors report the low-temperature synthesis of wafer-scale van der Waals nanomeshes composed of self-welding Te nanowires on various substrates, showing improved transport and photoelectric properties. [ABSTRACT FROM AUTHOR]

The performances of rechargeable batteries are strongly affected by the operating environmental temperature. In particular, low temperatures (e.g., ≤0 °C) are detrimental to efficient cell cycling. To circumvent this issue, we propose a few-layer Bi2Se3 (a topological insulator) as cathode material for Zn metal batteries. When the few-layer Bi2Se3 is used in combination with an anti-freeze hydrogel electrolyte, the capacity delivered by the cell at −20 °C and 1 A g−1 is 1.3 larger than the capacity at 25 °C for the same specific current. Also, at 0 °C the Zn | |few-layer Bi2Se3 cell shows capacity retention of 94.6% after 2000 cycles at 1 A g−1. This behaviour is related to the fact that the Zn-ion uptake in the few-layer Bi2Se3 is higher at low temperatures, e.g., almost four Zn2+ at 25 °C and six Zn2+ at −20 °C. We demonstrate that the unusual performance improvements at low temperatures are only achievable with the few-layer Bi2Se3 rather than bulk Bi2Se3. We also show that the favourable low-temperature conductivity and ion diffusion capability of few-layer Bi2Se3 are linked with the presence of topological surface states and weaker lattice vibrations, respectively. The performances of rechargeable batteries are detrimentally affected by low temperatures (e.g., < 0 °C). Here, the authors report a few-layer Bi2Se3 material capable of improving battery cycling performances when operational temperatures are shifted from +25 °C to −20 °C. [ABSTRACT FROM AUTHOR]

Due to the exciting photoelectric properties, better stability, and environmental-friendly nature, all-inorganic halide perovskites (AIHPs), especially the lead-free perovskites, have attracted worldwide attention. However, the film quality of AIHPs fabricated by typical spin-coating and subsequent high-temperature annealing is still not satisfactory, restricting their further development. Herein, we demonstrate a simple low-temperature solution-processed drop-casting method to achieve highly-crystalline cubic CsPbBr3 and lead-free layer-structured Cs3Sb2I9 microcrystals (MCs). This drop-casting technique not only consumes the less amount of precursor solution but also eliminates the high-temperature annealing as compared with those of spin coating. When these MCs are configured into photodetectors, they exhibit superior device performance, which is in distinct contrast to the one of spin-coated counterparts. Specifically, the responsivity of CsPbBr3 MCs is found to be as large as 8,990 mA/W, being 13 times larger than the spin-coated films and even better than many state-of-the-art solution-processed AIHPs devices. This device performance enhancement is attributed to the better film quality and phase purity obtained by the drop-casting method. All these results can evidently fill the "technology gap" for further enhancing the material quality of solution-processed AIHPs and breaking down the barriers that hinder the development of AIHPs based optoelectronic devices. [ABSTRACT FROM AUTHOR]

Due to the enhanced ambient structural stability and excellent optoelectronic properties, all-inorganic metal halide perovskite nanowires have become one of the most attractive candidates for flexible electronics, photovoltaics and optoelectronics. Their elastic property and mechanical robustness become the key factors for device applications under realistic service conditions with various mechanical loadings. Here, we demonstrate that high tensile elastic strain (∼ 4% to ∼ 5.1%) can be achieved in vapor-liquid-solid-grown single-crystalline CsPbBr3 nanowires through in situ scanning electron microscope (SEM) buckling experiments. Such high flexural elasticity can be attributed to the structural defect-scarce, smooth surface, single-crystallinity and nanomechanical size effect of CsPbBr3 nanowires. The mechanical reliability of CsPbBr3 nanowire-based flexible photodetectors was examined by cyclic bending tests, with no noticeable performance deterioration observed after 5,000 cycles. The above results suggest great application potential for using all-inorganic perovskite nanowires in flexible electronics and energy harvesting systems. [ABSTRACT FROM AUTHOR]

Hybrid organolead halide perovskites have attracted tremendous attention due to their recent success as high efficiency solar cell materials and their fascinating material properties uniquely suitable for optoelectronic devices. However, the poor ambient and operational stability as well as the concern of lead toxicity greatly hamper their practical utilization. In this work, crystalline, all-inorganic and lead-free Cs3Sb2I9 perovskite microplates are successfully synthesized by a two-step chemical vapor deposition method. As compared with other typical lead-free perovskite materials, the Cs3Sb2I9 microplates demonstrate excellent optoelectronic properties, including substantial enhancements in the Stokes shift, exciton binding energy and electron-phonon coupling. Simple photoconductive devices fabricated using these microplates exhibit an ultra-fast response with the rise and decay time constants down to 96 and 58 µs, respectively. This respectable photoconductor performance can be regarded as a record among all the lead-free perovskite materials. Importantly, these photodetectors show superior thermal stability in a wide temperature range, capable to function reversibly between 80 and 380 K, indicating their robustness to operate under both low and high temperatures. All these results evidently suggest the technological potential of inorganic lead-free Cs3Sb2I9 perovskite microplates for next-generation high-performance optoelectronic devices. [ABSTRACT FROM AUTHOR]

Esophageal candidiasis is a common opportunistic infection in immunocompromised hosts. Here, we report an aged man receiving long-term treatment with glucocorticoids, who is diagnosed with esophageal candidiasis. [ABSTRACT FROM AUTHOR]

Due to the ultra-thin nature and moderate carrier mobility, semiconducting two-dimensional (2D) materials have attracted extensive attention for next-generation electronics. However, the gate bias stress instability and hysteresis are always observed in these 2D materials-based transistors that significantly degrade their reliability for practical applications. Herein, the origin of gate bias stress instability and hysteresis for chemical vapor deposited monolayer WS2 transistors are investigated carefully. The transistor performance is found to be strongly affected by the gate bias stress time, sweeping rate and range, and temperature. Based on the systematical study and complementary analysis, charge trapping is determined to be the major contribution for these observed phenomena. Importantly, due to these charge trapping effects, the channel current is observed to decrease with time; hence, a rate equation, considering the charge trapping and time decay effect of current, is proposed and developed to model the phenomena with excellent consistency with experimental data. All these results do not only indicate the validity of the charge trapping model, but also confirm the hysteresis being indeed caused by charge trapping. Evidently, this simple model provides a sufficient explanation for the charge trapping induced gate bias stress instability and hysteresis in monolayer WS2 transistors, which can be also applicable to other kinds of transistors. [ABSTRACT FROM AUTHOR]

Designing highly efficient and low-cost electrocatalysts for oxygen evolution reaction is important for many renewable energy applications. In particular, strain engineering has been demonstrated as a powerful strategy to enhance the electrochemical performance of catalysts; however, the required complex catalyst preparation process restricts the implementation of strain engineering. Herein, we report a simple self-template method to prepare hierarchical porous Co3O4 nanowires (PNWs) with tunable compressive strain via thermal-oxidation-transformation of easily prepared oxalic acid-cobalt nitrate (Co(NO3)2) composite nanowires. Based on the complementary theoretical and experimental studies, the selection of proper solvents in the catalyst preparation is not only vital for the hierarchical structural evolution of Co3O4 but also for regulating their compressive surface strain. Because of the rich surface active sites and optimized electronic Co d band centers, the PNWs exhibit the excellent activity and stability for oxygen evolution reaction, delivering a low overpotential of 319 mV at 10 mA·cm−2 in 1 M KOH with a mass loading 0.553 mg·cm−2, which is even better than the noble metal catalyst of RuO2. This work provides a cost-effective example of porous Co3O4 nanowire preparation as well as a promising method for modification of surface strain for the enhanced electrochemical performance. [ABSTRACT FROM AUTHOR]

Tuberculosis remains a major global public health issue, among which extrapulmonary tuberculosis is significantly increasing. Furthermore, intestinal tuberculosis is the sixth most prevalent presentation of extrapulmonary tuberculosis. Here we report a case of cavernous pulmonary tuberculosis accompanied by intestinal tuberculosis. [ABSTRACT FROM AUTHOR]

Pancreas divisum is the most common congenital variant of the pancreatic ductal system and a potential cause of acute recurrent pancreatitis. Here, we report a middle-aged woman with acute recurrent pancreatitis due to pancreas divisum. [ABSTRACT FROM AUTHOR]

Amorphous indium—gallium—zinc oxide (a-IGZO) materials have been widely explored for various thin-film transistor (TFT) applications; however, their device performance is still restricted by the intrinsic material issues especially due to their non-crystalline nature. In this study, highly crystalline superlattice-structured IGZO nanowires (NWs) with different Ga concentration are successfully fabricated by enhanced ambient-pressure chemical vapor deposition (CVD). The unique superlattice structure together with the optimal Ga concentration (i.e., 31 at.%) are found to effectively modulate the carrier concentration as well as efficiently suppress the oxygen vacancy formation for the superior NW device performance. In specific, the In1.8Ga1.8Zn24O7 NW field-effect transistor exhibit impressive device characteristics with the average electron mobility of ~ 110 cm2·V−1·s−1 and on/off current ratio of ~ 106. Importantly, these NWs can also be integrated into NW parallel arrays for the construction of high-performance TFT devices, in which their performance is comparable to many state-of-the-art IGZO TFTs. All these results can evidently indicate the promising potential of these crystalline superlattice-structured IGZO NWs for the practical utilization in next-generation metal-oxide TFT device technologies. [ABSTRACT FROM AUTHOR]

Purpose: To perform contrast analysis of the relationship between high-resolution computed tomography (HRCT) signs and new pathologic classification of small GGNs-like lung adenocarcinoma.Materials and methods: The HRCT data from 145 pathologically confirmed cases of small GGNs of lung adenocarcinoma were analysed retrospectively. The 145 cases of GGNs were divided into pre-invasive (PI) group (n = 46), micro-invasive adenocarcinoma (MIA) group (n = 48), and invasive adenocarcinoma (IAC) group (n = 51). HRCT imaging sign of GGNs in each group was assessed and compared.Results: Significant differences in GGN size were found among the three groups (P < 0.05). The presence of a tumour-lung interface in the MIA and IAC groups was significantly higher than that in the PI group (P < 0.05), but no significant difference was found between the MIA and IAC groups. The presence of a pleural indentation sign in the IAC group was significantly higher than that in the other two groups (P < 0.05), but no significant difference was noted between the latter two groups. Significant differences were found in the lobulated and spicule signs among the three groups (P < 0.05). The presence of a microvascular sign in the MIA and IAC groups was significantly higher than that in the PI group (P < 0.05). No significant difference was found in the GGN density, vacuole sign, air bronchus sign and notch sign among the three groups.Conclusions: The HRCT signs of GGNs could be used to differentiate among pre-invasive lesions, micro-invasive lesions and invasive lung adenocarcinoma. [ABSTRACT FROM AUTHOR]

Although InO nanofibers (NFs) are well-known candidates as active materials for next-generation, low-cost electronics, these NF based devices still suffer from high leakage current, insufficient on-off current ratios ( I / I ), and large, negative threshold voltages ( V ), leading to poor device performance, parasitic energy consumption, and rather complicated circuit design. Here, instead of the conventional surface modification of InO NFs, we present a one-step electrospinning process (i.e., without hot-press) to obtain controllable Mg-doped InO NF networks to achieve high-performance enhancement-mode thin-film transistors (TFTs). By simply adjusting the Mg doping concentration, the device performance can be manipulated precisely. For the optimal doping concentration of 2 mol%, the devices exhibit a small V (3.2 V), high saturation current (1.1 × 10 A), large on/off current ratio (>10), and respectable peak carrier mobility (2.04 cm/(V·s)), corresponding to one of the best device performances among all 1D metal-oxide NFs based devices reported so far. When high- κ HfO thin films are employed as the gate dielectric, their electron mobility and V can be further improved to 5.30 cm/(V·s) and 0.9 V, respectively, which demonstrates the promising prospect of these Mg-doped InO NF networks for highperformance, large-scale, and low-power electronics. [ABSTRACT FROM AUTHOR]

Three Ag(I) coordination complexes, namely [Ag(2-stp)(2-apy)·3HO] ( 1), [Ag(2-stp)(2-apy)] ( 2) and [Ag(2-stp)(3-apy)(HO)] ( 3) (2-NaHstp = 2-sulfoterephthalic acid monosodium salt, 2-apy = 2-aminopyridine and 3-apy = 3-aminopyridine), have been synthesized and structurally characterized. They all show two-dimensional network structures. In complex 1, the Ag units are linked by stp ligands to form a 1D chain. Consequently, the 2-apy ligands link the adjacent 1D chain into 2D polymeric sheets. In 2, Ag1 and Ag2 atoms are bridged by stp ligands to form a 2D infinite sheet. In 3, the stp anion adopts a μ-(η,η):(η,η,η):(η,η) coordination mode to Ag units to 2D layer sheet and the network is consolidated by 3-apy ligands. The thermogravimetric analyses and photoluminescence of the complexes were also investigated. [ABSTRACT FROM AUTHOR]

Objectives: The soft palate in normal individuals exhibits morphological variety on cephalometry. The purpose of the present study was to explore its causes and investigate its possible effects in clinical practice. Methods: Cephalometric and cone-beam computed tomography (CBCT) data for 30 subjects were collected. The morphology of the soft palate on cephalometry was classified into two main types, eyebrow shape and spoon shape. Comparisons between these two types on both cephalometric and CBCT images were made. Results: Comparing these two types, there was a significant difference in the distance between the tip of the uvula and the palatopharyngeus ( p < 0.01) as well as in the angle between the uvula and the palatopharyngeus ( p < 0.01). The velar length on CBCT imaging was longer than that on cephalometry for the spoon-shape group ( p < 0.01) and the overall subjects ( p < 0.01). Conclusions: Based on the present results, we speculate that overlapping of the palatopharyngeus and the uvula, which is mainly determined by their relative positions, contributes to the contour of the soft palate on cephalometry. This overlapping phenomenon partly explains the morphological variety of the soft palate on cephalometry, and should be considered during measurement and evaluation of the soft palate. [ABSTRACT FROM AUTHOR]