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Interface engineering in atomically thin transition metal dichalcogenides (TMDs) is becoming an important and powerful technique to alter their properties, enabling new optoelectronic applications and quantum devices. Interface engineering in a monolayer WSe2 sample via introduction of high-density edges of standing structured graphene nanosheets (GNs) is realized. A strong photoluminescence (PL) emission peak from intravalley and intervalley trions at about 750 nm is observed at the room temperature, which indicated the heavily p-type doping of the monolayer WSe2/thin graphene nanosheet-embedded carbon (TGNEC) film heterostructure. We also successfully triggered the emission of biexcitons (excited state biexciton) in a monolayer WSe2, via the electron trapping centers of edge quantum wells of a TGNEC film. The PL emission of a monolayer WSe2/GNEC film is quenched by capturing the photoexcited electrons to reduce the electron-hole recombination rate. This study can be an important benchmark for the extensive understanding of light—matter interaction in TMDs, and their dynamics. [ABSTRACT FROM AUTHOR]

Revealing hydrothermal evolution from the early oxide to late carbonate stages for quartz–wolframite vein‐type deposits is essential for understanding the ore‐forming process. In this study, we choose the Baishitouwa tungsten polymetallic deposit located in the southern Great Xing'an Range tungsten belt as a case study, and present detailed deposit geology and in situ fluid inclusion (FI) analyses including microthermometry, laser Raman spectra, and LA‐ICP‐MS microanalysis to address this issue. Four stages of hydrothermal activity were identified: (1) quartz–wolframite (I), (2) quartz–wolframite (II)–pyrite–chalcopyrite, (3) quartz–polymetallic sulphides, and (4) quartz–carbonate. Four types of FIs were recognized: CO2‐rich, CO2‐bearing, liquid‐rich, and brine inclusions. Microthermometric data showed that the homogenization temperatures and salinities from the early to late stages are 380–460°C, 7.4–17.3, and 29.3–43.2 wt% NaCl equiv., 300–390°C and 7.1–17.0 wt% NaCl equiv., 220–320°C and 2.7–8.1 wt% NaCl equiv., and 150–250°C and 0.5–4.8 wt% NaCl equiv., respectively, suggesting a decreasing trend. Geochemically, all stage fluids contained high Rb and Mn concentrations, high Rb/Na, Cs/Na, Li/Na, K/Na, Rb/Sr, low K/Rb, and consistent Cs/Rb and Cs/(Na + K) ratios, indicating that the mineralizing fluids originated from a common source—an underlying, geochemically uniform, and highly fractionated granitic magma. Fluid immiscibility and cooling are the main mechanisms for wolframite precipitation, whereas greisenization is subordinate; the incursion of meteoric water into the hydrothermal system initiated at the sulphide stage, and fluid mixing is the dominant mechanism for sulphide precipitation. [ABSTRACT FROM AUTHOR]

Recent advances in developmental biology have been made possible by using multi-omic studies at single cell resolution. However, progress in plants has been slowed, owing to the tremendous difficulty in protoplast isolation from most plant tissues and/or oversize protoplasts during flow cytometry purification. Surprisingly, rapid innovations in nucleus research have shed light on plant studies in single cell resolution, which necessitates high quality and efficient nucleus isolation. Herein, we present efficient nuclei isolation protocols from the leaves of ten important plants including Arabidopsis, rice, maize, tomato, soybean, banana, grape, citrus, apple, and litchi. We provide a detailed procedure for nucleus isolation, flow cytometry purification, and absolute nucleus number quantification. The nucleus isolation buffer formula of the ten plants tested was optimized, and the results indicated a high nuclei yield. Microscope observations revealed high purity after flow cytometry sorting, and the DNA and RNA quality extract from isolated nuclei were monitored by using the nuclei in cell division cycle and single nucleus RNA sequencing (snRNA-seq) studies, with detailed procedures provided. The findings indicated that nucleus yield and quality meet the requirements of snRNA-seq, cell division cycle, and likely other omic studies. The protocol outlined here makes it feasible to perform plant omic studies at single cell resolution. [ABSTRACT FROM AUTHOR]

To investigate the prevalence of depression and anxiety in patients undergoing maintenance hemodialysis (MHD) in Hohhot, a large city on the northern border of China, and to identify independent risk factors for depression and anxiety in these patients. Patients receiving MHD for >3 months were enrolled in the four largest hemodialysis centers between September 2020 and December 2020. Depression and anxiety were assessed using the Zung self-rated depression scale (SDS) and Zung self-rated anxiety scale (SAS), respectively, with demographic and other data collected for logistic regression analyses. Among 305 MHD patients included in this study, the prevalence of depression was 55.1%, including 27.5%, 21.0%, and 6.6% with mild, moderate and severe cases, respectively. The prevalence of anxiety was 25.9%, with 20.0%, 4.6%, and 1.3% having mild, moderate, and severe cases, respectively. An independent protective factor for depression was family income of ≥1415 US dollars/month relative to <157 US dollars/month (odds ratio [OR] 0.209, 95% confidence interval [CI] 0.065–0.673), and predictors of depression included ≥3 comorbidities (OR 18.527, 95% CI 1.674–205.028) and severe pruritus (OR 15.971, 95% CI 5.173–49.315). Independent predictors of anxiety included infrequent exercise (OR 3.289, 95% CI 1.411–7.664) and severe pruritus (OR 5.912, 95% CI 1.733–20.168). The correlation between depression and anxiety in these patients was significant (rs = 0.775, p < 0.001). MHD patients in Northern China had high prevalence rates of depression (55.1%) and anxiety (25.9%). Lower family income, more comorbidities, and a higher degree of pruritus were predictors of depression, while infrequent exercise and severe pruritus were predictors of anxiety. Depression correlated significantly with anxiety. Attention should be given to family income, comorbidity, exercise, and pruritus severity for improved management of depression and anxiety among MHD patients. [ABSTRACT FROM AUTHOR]

The Dongji epithermal Au deposit formed in the Early Cretaceous is located in the Dongkeng volcanic Basin of the South China Block. The orebodies of the deposit are mainly hosted in the Jurassic volcanic–subvolcanic rocks. Here, detailed zircon U–Pb geochronology, major‐trace elements, and fluid inclusion data of the Dongji deposit are reported. At least two epochs of magmatic activity were identified at Dongji, including the Late Jurassic rhyolitic crystal tuff lava (165.3 ± 1.8 Ma to 162.8 ± 2.6 Ma) and quartz porphyry (156.0 ± 1.9 Ma), and the Early Cretaceous dacitic crystal tuff lava (108.4 ± 5.7 Ma) and purplish‐red crystal tuff lava (98.1 ± 0.8 Ma). The Late Jurassic volcanic–subvolcanic rocks are characterized by high SiO2 content, enriched LILE (large ion lithophile element) elements, depleted HFSE (high field strength element) elements, and obvious P, Ti and Eu anomalies. These geochemical characteristics suggest that the volcanic–subvolcanic rocks were generated by partial melting of the lower crust and controlled by fractional crystallization of Ti‐bearing phases, apatite, and plagioclase. In comparison, the Early Cretaceous volcanic–subvolcanic rocks are characterized by high K contents, and arc‐like signatures (e.g., enriched Rb, Th, K, and depleted Nb, Ta, Ti), indicating a partial melting of crust–mantle interaction under an extensional tectonic setting. The ore‐bearing dacitic crystal tuff lava and the caprock of purplish‐red tuff lava constrain the timing of gold mineralization in the range of 108–98 Ma. The Au mineralization at Dongji is divided into the early stage of quartz‐pyrite association and the late main mineralization stage of quartz‐polymetallic sulfide association. The fluid inclusion microthermometry results show that the ore‐forming fluids at the early mineralization are characterized by enrichment of liquid‐rich two‐phase inclusions and CO2‐bearing aqueous inclusions. The fluids with moderate homogenization temperatures (292–382°C) and low salinities (5.4–10.0 wt% NaClequiv) were possibly exsolved from magmatic rocks. Nevertheless, fluid inclusions in the late‐stage contain liquid‐rich two‐phase inclusions and pure liquid phase inclusions. The homogenization temperatures (222–309°C) and salinities (2.4–8.3 wt% NaClequiv) of the late‐stage fluid inclusions are relatively lower than those of the early stage, probably indicating a fluid mixing of magmatic and meteoric fluids. Based on the above, we propose that fluid mixing is the key factor facilitating Au precipitation in the Dongji deposit, probably applicable to other Au deposits in the Dongkeng volcanic Basin. [ABSTRACT FROM AUTHOR]

Ilmenite occurs as a common accessory mineral in igneous and metamorphic rocks and is a major constituent in lunar basaltic rocks. The distributions and concentrations of major and trace elements in ilmenite have potential to record temporal changes in melt chemistry and crystal fractionation processes. However, such data are scarce because of the limitations of in situ microanalytical technology, the lack of reference materials for trace elements, and the difficulties in analyzing the small needle-like shape of ilmenite. In this study, a natural ilmenite sample derived from the Panzhihua Fe–Ti–V oxide ore deposit was characterized for its major and trace elements in relation to the potential use as reference material. The homogeneity of the studied ilmenite (PZH12-09) was assessed by electron probe microanalysis (EPMA) and laser ablation inductively coupled plasma-mass spectrometry (LA-ICP-MS). It is homogeneous with relative standard deviation (RSD) values within ±3.76% for major elements (Fe, Ti, Mg, and Mn) and ±12.6% for trace elements (Sc, V, Cr, Co, Ni, Zr, Nb, Hf, and Ta), respectively. The relative deviations for major and trace elements determined by solution-mode ICP-MS and in situ microanalysis range from 0.11% to 7.71%, suggesting that the PZH12-09 ilmenite can be used as a reference material for in situ microanalysis. Furthermore, we developed a high-precision EPMA method to simultaneously determine the major and trace elements of ilmenite. The disadvantage of high detection limits and poor accuracy in trace element analyses were overcome by optimizing the analytical conditions, including the accelerating voltage (20 kV), beam current (200 nA), use of large Bragg crystals (LPET and LLIF), aggregate intensity counting, peak overlap and secondary standard corrections. The measured concentrations of most trace elements are consistent within 10% relative deviation compared with the reference values. The RSD values were within ±15% at various concentrations of trace elements (except for Ni and Nb), indicating the high accuracy and precision characteristics of the EPMA methodology. Detection limits for the trace elements vary from 11 to 27 μg g−1 (3σ). The developed method should provide robust trace element data for both extraterrestrial and terrestrial ilmenite samples at high spatial resolution (1–2 μm). [ABSTRACT FROM AUTHOR]

In this study, a novel type of composite explosive was prepared by adding titanium fiber into the RDX explosive. The effects of the content of titanium fiber on the performance of the RDX explosive were systematically studied, and the optimal concentration was obtained by comparing its performances with the RDX explosive. Underwater explosion experiments showed the optimal concentration was 15 mass%, in which the value of specific bubble energy, as well as total energy was acquired the maximum. Especially, the energy density of composite explosive with 10 mass% titanium fiber was 10.64 kJ·cm−3, compared with aluminum fiber explosive, which was increased by 17.96%. Meanwhile, results of the MTS809 machine indicated that the optimal concentration was 19.16 volume%, in which the ultimate stress increased by 175%, and critical strain increased by 393%. Additionally, better mechanical properties ensured process safety in the course of transportation and storage of explosives. Therefore, titanium fiber could be a potential energetic additive and played double roles in improving the properties of the RDX explosive significantly including detonation performances and anti-pressure ability. [ABSTRACT FROM AUTHOR]

Objectives. Urinary stem cells (USCs) have the capacity for unlimited growth and are promising tools for the investigations of cell differentiation and urinary regeneration. However, the limited life span significantly restricts their usefulness. This study is aimed at exploring the effect of integrin-linked kinase (ILK) on the smooth muscle cells (SMCs) differentiation of the dog USCs and investigating its molecular mechanism. Methods. An immortalized USCs cell line with the molecular markers and biological functions was prepared. After successfully inducing the differentiation of USCs into SMCs, the expression level of the unique key factor and its mechanisms in this process was determined through real-time polymerase chain reaction, Western blot, or Immunofluorescence staining. Results. We found that high cell density promoted USCs differentiation SMCs, and ILK was necessary for USCs differentiation into SMCs. Knocking down ILK decreased the expression of SMCs specific-marker, while using a selective ILK agonist increased the expression of SMCs specific-marker. Furthermore, ILK regulated SMCs differentiation in part through the activation of NF-κB pathway in USCs. A NF-κB activity assay showed overexpression of ILK could significantly upregulate NF-κB p50 expression, and NF-κB p50 acts as downstream signal molecular of ILK. Conclusion. High cell density induces the differentiation of USCs into SMCs, and ILK is a key regulator of myogenesis. Furthermore, NF-κB signaling pathway might play a crucial role in this process. [ABSTRACT FROM AUTHOR]

Undifferentiated sinonasal malignant melanoma (MM) is a rare type of tumor, which can be easily misdiagnosed. The present study reports a 41-year-old male patient who presented with a 4-day history of epistaxis. Clinical examination and radiological imaging lead to the detection of a mass in the right sinonasal region. Histopathological examination revealed that the mass was composed of malignant epithelioid cells arranged in nests and sheets. These cells displayed a hemangiopericytoma-like pattern with antler-like branching vessels. Immunohistochemical staining revealed that the tumor cells exhibited negative expression of melanocytic markers. This increased the difficulty of distinguishing undifferentiated MM from other malignant tumors located in the sinonasal area, particularly undifferentiated nasopharyngeal carcinoma. The diagnosis of undifferentiated MM was determined by ultrastructures, including the mature melanosomes and premelanosomes, in tumor cells by transmission electron microscopy. The present study suggests that the analysis of cancer stem cell marker and vasculogenic mimicry may be an important auxiliary tool for the diagnosis of MM. [ABSTRACT FROM AUTHOR]

More than 50% of Chinese mangroves were lost between 1950 and 2000 to habitat destruction, prompting an urge for conservation. To assess the importance of the protected Maowei Gulf mangrove estuary for fish population assemblage in the Beibu Gulf (China), we studied species composition and abundance of juvenile fish (including larvae) from July 2012 to June 2013. A total of 11 691 specimens were collected, which belonged to 24 species and 15 families. Six perciform species constituted 93% of the total sample. Pseudogobius javanicus (53.29%) was the dominant species from August to November, Omobranchus elegans (28.49%) from April to July, non-identified species in December and January, and Liza carinata in February and March. A number of commercially important fish species were also identified. Abundance was the highest in summer/early autumn (max 162.4 in Sep), and lowest in winter/early spring (Mar = 4.5). Diversity (H’) and richness (Dma) indices (both max. in May: 1.67 and 1.95 respectively) were generally positively correlated with tide and temperature, and negatively with salinity. Seasonal variations play a more important role in the fish assemblage structure than tidal rhythm, with differences particularly pronounced between colder and warmer months. Despite the prominent seasonal differences in abiotic factors, this study indicates that Maowei mangroves provide habitat and food for juvenile fish throughout the year and thus are indispensable for the fish diversity in the Beibu Gulf. [ABSTRACT FROM AUTHOR]

Mo8O264− based organic polyoxomolybdate salts of general formula [Hmim]4Mo8O26 (Hmim = 1-hexyl-3-methylimidazolium), [Dhmim]4Mo8O26 (Dhmim = 1,2-dimethyl-3-hexylimidazolium) and [Hpy]4Mo8O26·H2O (Hpy = 1-hexylpyridinium) have been prepared and characterized. These compounds were applied as catalysts for olefin epoxidation using hydrogen peroxide (H2O2) as oxidant in CH3CN. The polyoxomolybdate salts exhibit excellent catalytic performance and are also self-separating, a great advantage for catalyst recycling. The catalysts can be reused for at least 10 runs without significant loss of activity. [ABSTRACT FROM AUTHOR]

Supercapacitors are known as promising excellent electrochemical energy storage devices because of their attractive features, including quick charge and discharge, high power density, low cost and high security. In this work, a series of litchi-like Ni-Co selenide particles were synthesized via a simple solvothermal method, and the Ni-Co compositions were carefully optimized to tune the charge storage performance, charge storage kinetics, and conductivity for battery-like supercapacitors. Interestingly, the optimal sample Ni 0.95 Co 2.05 Se 4 exhibits a high capacity of 1038.75 F g -1 at 1 A g -1 and superior rate performance (retains 97.8% of the original capacity at 4 A g -1 ). Moreover, an asymmetric supercapacitor device was assembled based on the Ni 0.95 Co 2.05 Se 4 cathode and activated carbon anode. The device of Ni 0.95 Co 2.05 Se 4 //active carbon (AC) reveals a peak energy density of 37.22 W h kg -1 , and the corresponding peak power density reaches 800.90 W kg -1 . This work provides a facile and effective way to synthesize transition metal selenides as high-performance supercapacitor electrode materials., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

Neuregulin-1 type III is a key regulator in Schwann cell proliferation, committing to a myelinating fate and regulating myelin sheath thickness. However, the expression pattern of neuregulin-1 type III in the peripheral nervous system during developmental periods (such as the premyelinating stage, myelinating stage and postmyelinating stage) has rarely been studied. In this study, dorsal root ganglia were isolated from rats between postnatal day 1 and postnatal day 56. The expression pattern of neuregulin-1 type III in dorsal root ganglia neurons at various developmental stages were compared by quantitative real-time polymerase chain reaction, western blot assay and immunofluorescent staining. The expression of neuregulin-1 type III mRNA reached its peak at postnatal day 3 and then stabilized at a relative high expression level from postnatal day 3 to postnatal day 56. The expression of neuregulin-1 type III protein increased gradually from postnatal day 1, reached a peak at postnatal day 28, and then decreased at postnatal day 56. Immunofluorescent staining results showed a similar tendency to western blot assay results. Experimental findings indicate that the expression of neuregulin-1 type III in rat dorsal root ganglion was increased during the premyelinating (from postnatal day 2 to postnatal day 5) and myelinating stage (from postnatal day 5 to postnatal day 10), but remained at a high level in the postmyelinating stage (after postnatal day 10).

Molecular dynamics (MD) simulations were performed to study the structural properties of water molecules confined in functionalized carbon nanotubes (CNTs). Four CNTs, two armchair-type (6, 6), (7, 7) and two zigzag-type (10, 0), (12, 0) CNTs, representing different helicities and different diameters, were chosen and functionalized at their open ends by the hydrophilic -COOH and the hydrophobic -CH3 groups. The structural properties of water molecules inside the functionalized CNTs, including the orientation distributions of dipole moment and O-H bonds, the length of the single-file water chain, and the average number of hydrogen bonds, were analyzed during a process of simulations. MD simulation results in this work showed that the -CH3 functional groups exert little special effects on the structural properties of water molecules. It is mainly due to the relatively small size of the -CH3 group and its hydrophobic nature, which is consistent with hydrophobic CNTs. For CNTs functionalized by -COOH groups, the configurations of -COOH groups, incurvature or excurvature, determine whether water molecules can enter the CNTs. The incurvature or excurvature configurations of -COOH groups are the results of synergy effects of the CNTs' helicity and diameter and control the flow direction of water molecules in CNTs.

Carbon nanotubes show exceptional properties that render them promising candidates as building blocks for nanostructured materials. Many ambitious applications, ranging from molecular detection to membrane separation, require the delivery of fluids, in particular aqueous solutions, through the interior of carbon nanotubes (CNT). To foster such applications, an understanding of the properties of water molecules confined in carbon nanotubes at the molecular level is needed. In this work we report a study of temperature and helicity effects on static properties of water molecules confined in modified CNT by molecular dynamics simulations. It was found that the temperature has little effect on the confined water molecules in carbon nanotubes. But on the other hand, the simulation results showed that because of the difference in helicity between (6, 6) and (10, 0) CNTs, the modification by hydrophilic carboxyl acid functional groups (-COOH) results in a different response to the CNTs, which in turn have control over the flow direction of water molecules in these CNTs.