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The unique morphology of 2D van der Waals materials enables them to withstand large deformations and significant nonuniform strain, potentially inducing a strong flexoelectric effect. Despite the size‐dependent flexoelectric effect showing potential for modulating the optoelectronic performance of 2D van der Waals materials, it is far from being fully exploited owing to various challenges. Herein, the use of nanowires with different diameters as the bending media to fabricate 2D α‐In2Se3/β‐InSe heterojunctions with large curvatures of 0.1–1 µm−1 is proposed. The significant band alignment modulation in α‐In2Se3 resulting from the bending‐induced flexoelectric effect is verified through Kelvin probe force microscopy. The strain‐induced piezoelectric effect can be negated because of the weak vdW forces at the interface. The flexoelectric polarization in β‐InSe is screened via the accumulated electrons in the unilateral depleted heterojunction. Compared to the flat heterojunction, the curved heterojunction with an average curvature of 0.9 µm−1 shows 2.48‐fold and 7.62‐fold increases in open‐circuit voltage and zero‐biased responsivity, respectively. This study demonstrates the first successful modulation of photodetection in 2D heterojunctions by exploiting the flexoelectric effect, providing a new perspective for high‐performance 2D vdW optoelectronic devices. [ABSTRACT FROM AUTHOR]

Objectives. Diabetic nephropathy (DN) is a major cause of end-stage renal disease (ESRD) throughout the world, and the identification of novel biomarkers via bioinformatics analysis could provide research foundation for future experimental verification and large-group cohort in DN models and patients. Methods. GSE30528, GSE47183, and GSE104948 were downloaded from Gene Expression Omnibus (GEO) database to find differentially expressed genes (DEGs). The difference of gene expression between normal renal tissues and DN renal tissues was firstly screened by GEO2R. Then, the protein-protein interactions (PPIs) of DEGs were performed by STRING database, the result was integrated and visualized via applying Cytoscape software, and the hub genes in this PPI network were selected by MCODE and topological analysis. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analyses were carried out to determine the molecular mechanisms of DEGs involved in the progression of DN. Finally, the Nephroseq v5 online platform was used to explore the correlation between hub genes and clinical features of DN. Results. There were 64 DEGs, and 32 hub genes were identified, enriched pathways of hub genes involved in several functions and expression pathways, such as complement binding, extracellular matrix structural constituent, complement cascade related pathways, and ECM proteoglycans. The correlation analysis and subgroup analysis of 7 complement cascade-related hub genes and the clinical characteristics of DN showed that C1QA, C1QB, C3, CFB, ITGB2, VSIG4, and CLU may participate in the development of DN. Conclusions. We confirmed that the complement cascade-related hub genes may be the novel biomarkers for DN early diagnosis and targeted treatment. [ABSTRACT FROM AUTHOR]

Background. Diabetic nephropathy (DN) is one of the most common complications of diabetes mellitus and is a major cause of end-stage kidney disease. Cordyceps sinensis (Cordyceps, Dong Chong Xia Cao) is a widely applied ingredient for treating patients with DN in China, while the molecular mechanisms remain unclear. This study is aimed at revealing the therapeutic mechanisms of Cordyceps in DN by undertaking a network pharmacology analysis. Materials and Methods. In this study, active ingredients and associated target proteins of Cordyceps sinensis were obtained via Traditional Chinese Medicine Systems Pharmacology Database (TCMSP) and Swiss Target Prediction platform, then reconfirmed by using PubChem databases. The collection of DN-related target genes was based on DisGeNET and GeneCards databases. A DN-Cordyceps common target interaction network was carried out via the STRING database, and the results were integrated and visualized by utilizing Cytoscape software. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analyses were performed to determine the molecular mechanisms and therapeutic effects of Cordyceps on the treatment of DN. Results. Seven active ingredients were screened from Cordyceps, 293 putative target genes were identified, and 85 overlapping targets matched with DN were considered potential therapeutic targets, such as TNF, MAPK1, EGFR, ACE, and CASP3. The results of GO and KEGG analyses revealed that hub targets mainly participated in the AGE-RAGE signaling pathway in diabetic complications, TNF signaling pathway, PI3K-Akt signaling pathway, and IL-17 signaling pathway. These targets were correlated with inflammatory response, apoptosis, oxidative stress, insulin resistance, and other biological processes. Conclusions. Our study showed that Cordyceps is characterized as multicomponent, multitarget, and multichannel. Cordyceps may play a crucial role in the treatment of DN by targeting TNF, MAPK1, EGFR, ACE, and CASP3 signaling and involved in the inflammatory response, apoptosis, oxidative stress, and insulin resistance. [ABSTRACT FROM AUTHOR]

Kallmann syndrome (KS) is a rare human genetic disorder characterized by hypogonadotropic hypogonadism with the reduction or absence of olfactory sense. Mutations in multiple genes, including chemokine prokineticin‐2 (PROK2), are considered to contribute to the abnormal migration of gonadotropin‐releasing hormone neurons in the embryonic stage. However, the mechanisms of the different inheritance modes of KS have not been comprehensively determined. In this article, we present the case of one KS patient with the same mutation in PROK2 (c.223‐4C>A) as his mother. RNA sequencing analysis of his leukocytes showed a new transcript of PROK2, which contained a partial intron (192 bp) compared to those of his parents. Furthermore, we observed that hsa‐miR‐3195 was expressed at low levels in his and his father's sera compared to his mother's. Unexpectedly, hsa‐miR‐3195 was also identified to specifically target the 192 bp intron of the aberrant PROK2 transcript of this patient. We determined that high expression of hsa‐miR‐3195 could efficiently target aberrant PROK2 and stabilize the normal function of PROK2 in vitro, which provided a probable explanation for the different phenotypes of the patient and his mother with the same genotype. [ABSTRACT FROM AUTHOR]

Retaining learners and facilitating their continuance are critical for the mobile learning providers and educators. Drawing on stimulus‐organism‐response framework and self‐determination theory, this study examines factors that affect college students' mobile learning continuance by considering the self‐determination needs and learning involvement. A research model was developed and empirically tested against data collected from 309 college students who are the mobile learning users of an online education platform in China. The results of structural equation modeling analysis showed that perceived learning support, self‐management of learning and peer influence significantly influence affective learning involvement, which in turn positively affect mobile learning continuance intention. In addition, perceived learning support and peer influence also significantly influence cognitive learning involvement, which further determine mobile learning continuance intention. Theoretical and practical implications of these findings are also discussed. [ABSTRACT FROM AUTHOR]

Abstract: Inversion symmetry broken 3R phase semiconducting transition metal dichalcogenides (TMDC) have huge potential applications in many novel fields, such as valleytronics and nonlinear optics for the strong spin–orbit coupling and particularly the persistent noncentrosymmetric structure regardless the layer numbers, in stark contrast to the strict layer number requirement in other phases. Unfortunately, the fabrication of 3R phase TMDC is still a huge task to date. Molybdenum telluride (MoTe2) attracts increasing interest in recent years due to the easy transition between its various phases and its narrow bandgap close to silicon. However, the weak Mo–Te bond and the small energy imparity among phases make it a big challenge to obtain pure‐phase single crystalline MoTe2, especially; it is still a virgin land to obtain two‐dimensional (2D) 3R‐MoTe2. Here, by rational controlling the deposition temperature and tellurization velocity, for the first time high quality 2D 3R‐MoTe2 flakes are synthesized via chemical vapor deposition from a MoCl5 precursor. Scanning transmission electron microscopy unambiguously reveals the 3R stacking mode of as‐synthesized MoTe2. Second harmonic generation measurement confirms the excellent odd/even layer‐independent frequency conversion efficiency. Besides, the outstanding intrinsic infrared detection ability of as‐synthesized 3R‐MoTe2 is demonstrated as well. [ABSTRACT FROM AUTHOR]

Abstract: Infrared light detection is generally limited by the intrinsic bandgap of semiconductors, which suppresses the freedom in infrared light photodetector design and hinders the development of high‐performance infrared light photodetector. In this work, for the first time infrared light (1030 nm) photodetectors are fabricated based on WS2/MoS2 heterostructures. Individual WS2 and MoS2 have no response to infrared light. The origin of infrared light response for WS2/MoS2 comes from the strong interlayer coupling which shrinks the energy interval in the heterojunction area thus rendering heterostructures longer wavelength detection ability compared to individual components. Considering the low light absorption due to indirect bandgap essence of few layers WS2/MoS2 heterostructures, its infrared responsivity is further enhanced with at most ≈25 times but the fast response rate is maintained via surface plasmon resonance (SPR). Such an interlayer coupling induced infrared light response and surface plasmon resonance enhancement strategy paves the way for high‐performance infrared light photodetection of infinite freedom in design. [ABSTRACT FROM AUTHOR]

Summary: Cytosine methylation is an essential feature of epigenetic regulation and is involved in various biological processes. Although cytosine methylation has been analysed at the genomic scale for several plant species, there is a general lack of understanding of the dynamics of global and genic DNA methylation in plants growing in environments challenged with biotic and abiotic stresses. In this study, we mapped cytosine methylation at single‐base resolution in the genome of commercial apple (Malus x domestica), and analysed changes in methylation patterns associated with water deficit in representative drought‐sensitive and drought‐tolerant cultivars. We found that the apple genome exhibits ~54%, ~38% and ~8.5% methylation at CG, CHG and CHH sequence contexts, respectively. We additionally documented changes in gene expression associated with water deficit in an attempt to link methylation and gene expression changes. Global methylation and transcription analysis revealed that promoter‐unmethylated genes showed higher expression levels than promoter‐methylated genes. Gene body methylation appears to be positively correlated with gene expression. Water deficit stress was associated with changes in methylation at a multitude of genes, including those encoding transcription factors (TFs) and transposable elements (TEs). These results present a methylome map of the apple genome and reveal widespread DNA methylation alterations in response to water deficit stress. These data will be helpful for understanding potential linkages between DNA methylation and gene expression in plants growing in natural environments and challenged with abiotic and biotic stresses. [ABSTRACT FROM AUTHOR]

As a layered p-type semiconductor with a wide bandgap of 2.7 eV, GeSe2 can compensate for the rarity of p-type semiconductors, which are desired for the production of high-integration logic circuits with low power consumption. Herein, ultrathin 2D single crystals of β-GeSe2 are produced using van der Waals epitaxy and halide assistance; each crystalline flake is ≈7 nm thick and shaped as a rhombus. The optical and electrical properties of the flakes are studied systematically, and the temperature-dependent Raman spectra of the flakes reveal that the intensity of the Raman peaks decrease with increasing temperature. Low-temperature electrical measurements suggest that the variable-range hopping model is best for describing the electrical transport at 20-180 K; meanwhile, optical-phonon-assisted hopping can account for the transport behavior at 180-460 K. Impressively, the angle-resolved polarized Raman measurements indicate strong in-plane anisotropy of the rhombic GeSe2 flake under a parallel polarization configuration, which may result from the low symmetry of the monoclinic crystal structure of GeSe2. Furthermore, a photodetector based on a rhombic GeSe2 flake is constructed and shown to exhibit a high responsivity of 2.5 A W−1 and a fast response of ≈0.2 s. [ABSTRACT FROM AUTHOR]

Aim The expression of vascular endothelial growth factor (VEGF) by cancer cells has been identified as a factor that is associated with lymph node metastasis (LNM) in some cancers, but an accurate description of the relation between VEGF and LNM in cervical cancer is lacking. We conducted a concurrent meta-analysis to investigate this issue. Methods We searched PubMed and EMBASE for articles addressing the association between VEGF and cervical cancer. We used stata 12.0 and calculated the crude odds ratios (OR) and corresponding 95% confidence intervals (CI). Heterogeneity between the studies included was assessed by Cochran's Q-test. Results Overall, 16 relevant studies with 426 cases and 751 controls were included in our study. The results demonstrated that cervical cancer patients with VEGF-positive expression had a 2.87-fold higher risk of LNM than patients without VEGF-positive expression (95%CI = 1.85-4.44, P < 0.001). Furthermore, subgroup analysis by ethnicity revealed that VEGF-positive expression could increase the risk of LNM in cervical cancer among Asian populations (OR = 2.55, 95%CI = 1.61-4.03, P < 0.001) and Caucasian populations (OR = 8.81, 95%CI = 2.78-27.88, P < 0.001). Moreover, subgroup analysis by country revealed that VEGF-positive expression could increase the risk of LNM in cervical cancer among Chinese populations (OR = 3.38, 95%CI = 2.18-5.25, P < 0.001) but not among Korean populations ( P = 0.84) or Japanese populations ( P = 0.06). Subgroup analysis based on sample size proved that VEGF-positive expression was statistically associated with LNM in a large sample group. Conclusion Our study revealed that VEGF-positive expression is related with higher risk of LNM in cervical cancer. [ABSTRACT FROM AUTHOR]

Melatonin mediates many physiological processes in plants. We investigated its role in regulating growth, potassium uptake, and root system architecture under three types of stress: salinity or a deficiency of all nutrients in Malus hupehensis Rehd., as well as a K deficiency in Malus rockii Rehd. Each treatment caused a reduction in growth rates and disrupted the absorption of potassium. However, pretreatment with 0.1 mmol/L melatonin significantly alleviated such inhibitions. The addition of melatonin also upregulated genes for antioxidant enzymes involved in the ascorbate-glutathione cycle ( MdcAPX, MdDHAR1, MdDHAR2, MdMDHAR, and MdcGR) and helped decrease the accumulation of H2O2 while improving the expression of K transporters and genes for the CBL1- CIPK23 pathway. These results indicated that melatonin can regulate the ROS signal and activate the CBL1- CIPK23 pathway to regulate the expression of a potassium channel protein gene, thereby promoting the absorption of potassium ions. Our findings demonstrate that inducing melatonin production is an important mechanism for plant defenses that can serve as a platform for possible applications in agricultural or related fields of research. [ABSTRACT FROM AUTHOR]

GaTe is an important III–VI semiconductor with direct bandgap; thus, it holds great potential in the field of optoelectronics. Although it is known that GaTe can exist both in monoclinic and hexagonal phases, current studies are still exclusively restricted to the monoclinic phase of two dimensional (2D) GaTe owing to the difficulty in the fabrication of 2D hexagonal GaTe. Both monoclinic and hexagonal GaTe are demonstrated in this work, which can be selectively synthesized via a physical vapor deposition method, under precisely controlled growth temperatures. The pristine Raman and non‐linear optical properties of hexagonal GaTe has been systematically explored for the first time; moreover, a novel selected‐area phase transition from hexagonal to monoclinic of GeTe has been achieved via fs‐laser irradiation. This work may pave the way for widely use of 2D GaTe in various fields in future. [ABSTRACT FROM AUTHOR]

Two dimensional (2D) magnetic materials display enormous application potential in spintronic fields. However, most of currently reported magnetic materials are van der Waals layered structure that is easy to be isolated via exfoliation method. By contrast, the studies on non‐van der Waals ultrathin magnetic materials are rare, largely due to the difficulty in fabrication. Rhombohedral Cr2S3, an intensively studied antiferromagnetic transition metal chalcogenide with Neel temperature of ≈120 K, has a typical non‐van der Waals structure. Restricted by the strong covalent bonding in all the three dimensions of non‐van der Waals structure, the synthesis of ultrathin Cr2S3 single crystals is still a challenge that is not achieved yet. Besides, the study on the Raman modes of rhombohedral Cr2S3 is also absent. Herein, by employing space‐confined chemical vapor deposition strategy, ultrathin rhombohedral Cr2S3 single crystals with a thickness down to ≈2.5 nm for the first time are successfully grown. Moreover, a systematically investigation is also conducted on the Raman vibrations of ultrathin rhombohedral Cr2S3. With the aid of angle‐resolved polarized Raman technique, the Raman modes of rhombohedral Cr2S3 for the first time based on crystal symmetry and Raman selection rules are rationally assigned. By combining space‐confined chemical vapor deposition and van der Waals substrate, ultrathin Cr2S3 single crystals with a thickness of 2.5 nm are synthesized for the first time. With the aid of the angle‐resolved polarized Raman technique, the Raman modes of rhombohedral Cr2S3 are rationally assigned based on crystal symmetry and Raman selection rules. [ABSTRACT FROM AUTHOR]

Transition metal dichalcogenides (TMDs) consist of dozens of ultrathin layered materials that have significantly different properties due to their varied phases, which determine the properties and application range of TMDs. Interestingly, a controllable phase transition in TMDs is achieved extensively with the use of several methods. Thus, phase control is a promising way to fully exploit the potential of TMDs. This review introduces the recent rapid development of the study of the TMD phase control, starting from the basic conception of the phase and phase transition in TMDs to the strategies for obtaining phase control. The different strategies are roughly classified into several types based on their characteristics: doping, synthesis method, strain, thermal method, and interlayer coupling. Finally, an evaluation on the prospect of the emergent strategies is provided. 2D transition metal dichalcogenides (TMDs) have various stable phases. Phase determines the basic properties of 2D TMDs. Thus, how to precisely control the phase of TMDs is the key issue for the full utilization of TMDs in future. Here, the main strategies for triggering phase transition in 2D TMDs are summarized and evaluated for future research. [ABSTRACT FROM AUTHOR]

Inversion symmetry broken 3R phase semiconducting transition metal dichalcogenides (TMDC) have huge potential applications in many novel fields, such as valleytronics and nonlinear optics for the strong spin–orbit coupling and particularly the persistent noncentrosymmetric structure regardless the layer numbers, in stark contrast to the strict layer number requirement in other phases. Unfortunately, the fabrication of 3R phase TMDC is still a huge task to date. Molybdenum telluride (MoTe2) attracts increasing interest in recent years due to the easy transition between its various phases and its narrow bandgap close to silicon. However, the weak Mo–Te bond and the small energy imparity among phases make it a big challenge to obtain pure‐phase single crystalline MoTe2, especially; it is still a virgin land to obtain two‐dimensional (2D) 3R‐MoTe2. Here, by rational controlling the deposition temperature and tellurization velocity, for the first time high quality 2D 3R‐MoTe2 flakes are synthesized via chemical vapor deposition from a MoCl5 precursor. Scanning transmission electron microscopy unambiguously reveals the 3R stacking mode of as‐synthesized MoTe2. Second harmonic generation measurement confirms the excellent odd/even layer‐independent frequency conversion efficiency. Besides, the outstanding intrinsic infrared detection ability of as‐synthesized 3R‐MoTe2 is demonstrated as well. Inversion symmetry broken 2D 3R‐MoTe2 single crystals are synthesized by chemical vapor deposition for the first time. Such a novel noncentrosymmetric structure renders it with high frequency conversion efficiency in second harmonic generation and strong spin–orbit coupling, suggesting its promising future in the applications of nonlinear optics and valleytronics. [ABSTRACT FROM AUTHOR]

Abstract: Inversion symmetry broken 3R phase semiconducting transition metal dichalcogenides (TMDC) have huge potential applications in many novel fields, such as valleytronics and nonlinear optics for the strong spin–orbit coupling and particularly the persistent noncentrosymmetric structure regardless the layer numbers, in stark contrast to the strict layer number requirement in other phases. Unfortunately, the fabrication of 3R phase TMDC is still a huge task to date. Molybdenum telluride (MoTe2) attracts increasing interest in recent years due to the easy transition between its various phases and its narrow bandgap close to silicon. However, the weak Mo–Te bond and the small energy imparity among phases make it a big challenge to obtain pure‐phase single crystalline MoTe2, especially; it is still a virgin land to obtain two‐dimensional (2D) 3R‐MoTe2. Here, by rational controlling the deposition temperature and tellurization velocity, for the first time high quality 2D 3R‐MoTe2 flakes are synthesized via chemical vapor deposition from a MoCl5 precursor. Scanning transmission electron microscopy unambiguously reveals the 3R stacking mode of as‐synthesized MoTe2. Second harmonic generation measurement confirms the excellent odd/even layer‐independent frequency conversion efficiency. Besides, the outstanding intrinsic infrared detection ability of as‐synthesized 3R‐MoTe2 is demonstrated as well. [ABSTRACT FROM AUTHOR]