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The intercity daily flow of long stay international visitors (LSIV) reflects the economic globalisation and regional integration of a region. We made the first attempt to use mobile phone data to identify international visitors who stayed longer than one month in the Yangtze River Delta (YRD) region in 2019, analysed the spatial patterns of LSIV, and revealed the impact factors associated with the daily intercity flow of LSIV. We discussed spatial dependence using multiscale geographically weighted regression (MGWR), and performed cluster analysis to understand the combination effects. The results show that enterprises have the largest effect, AQI and administrative hierarchy have relatively low effects, and income, imports and exports do not have any significant effect. Overall, the economically developed eastern regions of the YRD region are more attractive for daily travel by LSIV, with the Shanghai metropolitan area being the most attractive. Our findings provide new insights into the relationship between the intercity daily flow of LSIV and the urban economy and society in the delta region to help suggest planning recommendations to enhance the globalisation development strategy and provide a better environment for international visitors in the delta region.
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Teléfono Celular , Ríos , China , Análisis por Conglomerados , RentaRESUMEN
MicroRNA-142-3p (miR-142-3p) has been reported to be implicated in colon cancer; however, the possible regulatory mechanisms and molecular subtypes regulated by miR-142-3p have not been fully elucidated. This study aimed to investigate the biological functions and regulatory mechanism of miR-142-3p in colon cancer. The expression level of miR-142-3p in colon cancer was analyzed based on the mRNA and miRNA expression datasets of colon cancer retrieved from The Cancer Genome Atlas. Target genes of miR-142-3p were also predicted. Based on these target genes, the functions and subtypes of miR-142-3p were investigated. The metabolic and tumor-related pathways, immune microenvironment, and target gene expression between the 2 subtypes were analyzed. MiR-142-3p was upregulated in tumor tissues, and its high expression indicated a poor prognosis. A total of 39 target genes were predicted, which were significantly involved in autophagy- and metabolism-related functions and pathways. Based on these target genes, the colon cancer samples were clustered into 2 subtypes. There were 35 metabolism-related pathways that were significantly different between the 2 clusters. The immune and stromal scores in cluster 2 were higher than those in cluster 1, whereas the tumor purity of cluster 2 was significantly lower than that of cluster 1. TP53INP2 expression in cluster 2 was higher than that in cluster 1. MiR-142-3p may promote colon cancer progression via autophagy- and metabolism-related pathways. MiR-142-3p may be served as a candidate target for the treatment of colon cancer.
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Neoplasias del Colon , MicroARNs , Humanos , Neoplasias del Colon/patología , MicroARNs/genética , MicroARNs/metabolismo , Regulación Neoplásica de la Expresión Génica , Microambiente Tumoral/genética , Proteínas Nucleares/genéticaRESUMEN
Nonstoichiometric compounds are widely used in contemporary energy technologies due to their high surface polarity, tailored electronic structure, high electrical conductivity, and other enhanced properties. However, the preparation of such nonstoichiometric compounds can be complicated and, in some cases, uncontrollable and dangerous. Here, we report a "one-pot" strategy for synthesizing N-doped porous graphitic carbon that is hybridized with nonstoichiometric scandium oxide (denoted as ScO0.95@N-PGC) and show that the composite significantly promotes sulfur cathode kinetics in lithium-sulfur (Li-S) batteries. The synthesis of the ScO0.95@N-PGC composite entails heating a porous dry gel that consists of a C source (glucose), a N source (dicyandiamide), and a Sc source (Sc(NO3)3·H2O). Thermally decomposing the dicyandiamide creates a highly reductive atmosphere that simultaneously affords the hypoxic state of the ScO0.95 and dopes the carbon matrix with nitrogen. Density functional theory reveals the presence of oxygen vacancies that enable the ScO0.95 crystals to function as excellent electrical conductors, exhibit enhanced adsorption toward polysulfides, and accelerate the cathode reactions by lowering the corresponding activation energies. Moreover, Li-S cells prepared from the ScO0.95@N-PGC composite display a high specific capacity (1046 mA h g-1 at 0.5 C), an outstanding cycling stability (641 mA h g-1 after 1000 charge-discharge cycles at 0.5 C, a capacity decay of 0.038% per cycle), and a particularly outstanding rate capability (438 mA h g-1 at 8 C). The methodology described establishes a sustainable approach for synthesizing nonstoichiometric compounds while broadening their potential utility in a broad range of energy technologies.
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Lithium-sulfur (Li-S) batteries hold great promise for widespread application on account of their high theoretical energy density (2600 Wh kg-1 ) and the advantages of sulfur. Practical use, however, is impeded by the shuttle effect of polysulfides along with sluggish cathode kinetics. it is reported that such deleterious issues can be overcome by using a composite film (denoted as V-CMP@MWNT) that consists of a conjugated microporous polymer (CMP) embedded with vanadium single-atom catalysts (V SACs) and a network of multi-walled carbon nanotubes (MWNTs). V-CMP@MWNT films are fabricated by first electropolymerizing a bidentate ligand designed to coordinate to V metals on self-standing MWNT films followed by treating the CMP with a solution containing V ions. Li-S cells containing a V-CMP@MWNT film as interlayer exhibit outstanding performance metrics including a high cycling stability (616 mA h g-1 at 0.5 C after 1000 cycles) and rate capability (804 mA h g-1 at 10 C). An extraordinary area-specific capacity of 13.2 mA h cm-2 is also measured at a high sulfur loading of 12.2 mg cm-2 . The underlying mechanism that enables the V SACs to promote cathode kinetics and suppress the shuttle effect is elucidated through a series of electrochemical and spectroscopic techniques.
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Despite significant progress in the preparation and characterization of two-dimensional (2D) materials, the synthesis of 2D organic materials remains challenging. Here, we report a novel space-confined polymerization method that enables the large-scale synthesis of 2D sheets of a functional conjugated polymer, namely, poly(3,4-ethylenedioxythiophene) (PEDOT). A key step in this method is the confinement of monomer to the boundaries of ice crystals using micelles. This spatial confinement directs the polymerization to form 2D PEDOT sheets with high crystallinity and controlled morphology. Supercapacitors prepared from the 2D PEDOT sheets exhibit outstanding performance metrics. In aqueous electrolyte, a high areal specific capacitance of 898â mF cm-2 at 0.2â mA cm-2 along with an excellent rate capability is achieved (e.g., capacitance retention of 67.6 % at a 50-fold higher current). Moreover, the 2D PEDOT-based supercapacitors exhibit outstanding cycling stability (capacitance retention of 98.5 % after 30,000 cycles). Device performance is further improved when an organic electrolyte is used.
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Red phosphorus (RP) is a promising anode material for use in lithium-ion batteries (LIBs) due to its high theoretical specific capacity (2596 mA h g-1). However, the practical use of RP-based anodes has been challenged by the material's low intrinsic electrical conductivity and poor structural stability during lithiation. Here, we describe a phosphorus-doped porous carbon (P-PC) and disclose how the dopant improves the Li storage performance of RP that was incorporated into the P-PC (designated as RP@P-PC). P-doping porous carbon was achieved using an in situ method wherein the heteroatom was added as the porous carbon was being formed. The phosphorus dopant effectively improves the interfacial properties of the carbon matrix as subsequent RP infusion results in high loadings, small particle sizes, and uniform distribution. In half-cells, an RP@P-PC composite was found to exhibit outstanding performance in terms of the ability to store and utilize Li. The device delivered a high specific capacitance and rate capability (1848 and 1111 mA h g-1 at 0.1 and 10.0 A g-1, respectively) as well as excellent cycling stability (1022 mA h g-1 after 800 cycles at 2.0 A g-1). Exceptional performance metrics were also measured when the RP@P-PC was used as an anode material in full cells that contained lithium iron phosphate as the cathode material. The methodology described can be extended to the preparation of other P-doped carbon materials that are employed in contemporary energy storage applications.
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Electrocatalysis is critical to the performance displayed by sulfur cathodes. However, the constituent electrocatalysts and the sulfur reactants have vastly different molecular sizes, which ultimately restrict electrocatalysis efficiency and hamper device performance. Herein, the authors report that aggregates of cobalt single-atom catalysts (SACs) attached to graphene via porphyrins can overcome the challenges associated with the catalyst/reactant size mismatch. Atomic-resolution transmission electron microscopy and X-ray absorption spectroscopy measurements show that the Co atoms present in the SAC aggregates exist as single atoms with spatially resolved dimensions that are commensurate the sulfur species found in sulfur cathodes and thus fully accessible to enable 100% atomic utilization efficiency in electrocatalysis. Density functional theory calculations demonstrate that the Co SAC aggregates can interact with the sulfur species in a synergistic manner that enhances the electrocatalytic effect and promote the performance of sulfur cathodes. For example, Li-S cells prepared from the Co SAC aggregates exhibit outstanding capacity retention (i.e., 505 mA h g-1 at 0.5 C after 600 cycles) and excellent rate capability (i.e., 648 mA h g-1 at 6 C). An ultrahigh area specific capacity of 12.52 mA h cm-2 is achieved at a high sulfur loading of 11.8 mg cm-2 .
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Two-dimensional (2D) organic materials hold great promise for use in a multitude of contemporary applications due to their outstanding chemical and physical properties. Herein, 2D sheets of poly(3,4-ethylenedioxythiophene):poly(4-styrenesulfonate) (PEDOT:PSS) are prepared from a commercially available PEDOT:PSS suspension using ice as a template. The 2D PEDOT:PSS sheets grow in the boundaries of ice crystals as the polymers are "squeezed" out of the suspension when the water solidifies. The mechanical robustness of the sheets can be enhanced by incorporating WO3 nanowires, and the PSS component can be conveniently removed with a concentrated solution of H2SO4 to afford stable suspensions of PEDOT or WO3@PEDOT sheets, either of which can be converted into flexible films with tunable thicknesses via filtration. Swagelok- or pouch-type supercapacitor devices prepared from the WO3@PEDOT films exhibit outstanding energy-storage characteristics, including high rate capability, thickness-independent energy storage (e.g., 701 mF cm-2 is achieved with a 1-mm-thick film), high resistance toward mechanical deformation, and good cycling stability. Additionally, a high energy density of 0.083 mWh cm-2 is measured for a device prepared using a 1-mm-thick film at a high power density of 10 mW cm-2. The methodology described establishes an efficient and readily scalable approach for accessing 2D organic sheets.
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The reaction kinetics of sulfur cathodes generally control the performance of lithium-sulfur (Li-S) batteries. Here, N-doped porous graphitic carbon with bound VN nanocrystals (3D VN@N-PGC), which is synthesized in one pot by heating a mixture of glucose as C source, urea as N source, and NH4 VO3 as V source, is reported to be an superior electrocatalytic cathode host for Li-S batteries. Notably, the VN nanocrystals, strongly bound to the N-PGC network, form via in situ reactions among the thermolytic products of starting materials. The dopant N atoms and bound VN nanocrystals exhibit synergistic electrocatalytic effects to promote the cathode reactions of the Li-S cells. The observed enhancements are supported by density functional theory simulations and by the observation of electrocatalytic N- and V-intermediate species, via X-ray absorption near-edge structure spectroscopy. Li-S cells assembled using 3D VN@N-PGC as cathode host exhibit superior performance in terms of specific capacity (1442 mA h g-1 at 0.1 C), rate capability (641 mA h g-1 at 4 C), and cycle life (466 mA h g-1 after 1700 cycles at 2 C, corresponding to a capacity decay of 0.020% per cycle). The one-pot methodology is facile and scalable and offers a new approach for synthesis of various metal nitride-containing materials for other electrocatalytic applications.
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We have synthesized single crystals of iron-based superconducting Ca10(Pt4As8)((Fe0.86Pt0.14)2As2)5 and performed extensive measurements on their transport properties. A remarkable difference in the behavior and a large anisotropy between in-plane and out-of-plane resistivity was observed. Disorder could explain the in-plane square-root temperature dependence resistivity, and interlayer incoherent scattering may contribute to the out-of-plane transport property. Along the ab plane, the estimated value of the coherence length is 15.5 Å. From measurements of the upper critical magnetic field Hc2 (T ≥ 20 K), we estimate Hc2(0) = 313 T. Thermal conductivity for Ca10(Pt4As8)((Fe0.86Pt0.14)2As2)5 is relatively small, which can be accounted for by the disorder in the crystal and the low-charge carrier density as verified by the Hall effect.
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Nucleotide excision repair (NER) is a DNA damage repair mechanism in mammals, but the relationship between NER and human colorectal cancer (HRC) progression has not been clarified yet. In this study, the expression of the NER genes XPA, XPC, XPF, XPG, ERCC1, and XPD was measured in normal and cancerous human colorectal tissue. Among them, only the XPC gene expression was significantly increased in colorectal cancer tissue. To establish the role of XPC in colorectal cancer, small interference RNA (siRNA) targeting XPC was used to knockdown the expression of XPC in HRC cell lines. In addition, an expression vector plasmid containing the XPC cDNA was constructed and stably transfected into HRC cell lines to overexpress the XPC gene. Interestingly, MTT and apoptosis assay demonstrated that XPC gene overexpression significantly increased the susceptibility of HRC cell lines to cisplatin and X-ray radiation. In order to study the relationship between XPC expression and the progression of HRC, XPC expression was measured in 167 patients with colorectal cancer. The results showed that patients with high XPC expression had longer survival time. Cox regression analysis showed that high XPC expression might be a potential predictive factor for colorectal cancer. In conclusion, XPC plays a key role in the susceptibility of colorectal cancer to chemotherapy and ionizing radiation and is associated with a good patients' prognosis.
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Lowdensity lipoprotein receptors (LDLRs) may serve a role in the diabetogenic effect of statins; however, the effects of statins on LDLR expression and its regulation in the pancreas and islets have yet to be determined. To exclude the longterm effects of treatment with atorvastatin, which allows mice to adapt, male C57BL/j and apolipoprotein Edeficient mice were acutely treated with oral atorvastatin for 6 weeks, and glucose homeostasis and LDLR expression in the pancreas and islets were examined. In the present study, it was observed that the shortterm use of atorvastatin affected insulin sensitivity in normal mice and glucose tolerance in hyperlipidemic mice. Furthermore, it was identified that 6 weeks of treatment with atorvastatin suppressed LDLR expression in the pancreas and pancreatic islets in C57BL/j mice, and an increase in proprotein convertase subtilisin/kexin type 9 expression was additionally observed in the pancreas. However, 6 weeks of treatment with atorvastatin did not affect LDLR expression in the pancreas of hyperlipidemic mice. It may be concluded that the shortterm use of atorvastatin disturbs glucose homeostasis and suppresses LDLR expression in the pancreas and pancreatic islets in C57BL/j mice, suggesting that the role of LDLR in the diabetogenic effect of statins requires further investigation.
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Atorvastatina/farmacología , Regulación hacia Abajo/efectos de los fármacos , Glucosa/metabolismo , Islotes Pancreáticos/metabolismo , Receptores de LDL/metabolismo , Transportador 1 de Casete de Unión a ATP/genética , Transportador 1 de Casete de Unión a ATP/metabolismo , Animales , Células Cultivadas , Hiperlipidemias/metabolismo , Hiperlipidemias/patología , Hiperlipidemias/veterinaria , Islotes Pancreáticos/citología , Lípidos/sangre , Masculino , Ratones , Ratones Endogámicos C57BL , Ratones Noqueados , Proproteína Convertasa 9/sangre , Proproteína Convertasa 9/genética , Proproteína Convertasa 9/metabolismo , Receptores de LDL/genética , Proteína 2 de Unión a Elementos Reguladores de Esteroles/genética , Proteína 2 de Unión a Elementos Reguladores de Esteroles/metabolismo , Ubiquitina-Proteína Ligasas/genética , Ubiquitina-Proteína Ligasas/metabolismoRESUMEN
To treat retinal degenerative diseases, a transcorneal electrical stimulation-based system is proposed, which consists of an eye implant and an external component. The eye implant is wirelessly powered and controlled by the external component to generate the required bi-polar current pattern for transcorneal stimulation with an amplitude range of 5 µA to 320 µA, a frequency range of 10 Hz to 160 Hz and a duty ratio range of 2.5% to 20%. Power delivery control includes power boosting in preparation for stimulation, and normal power regulation that adapts to both coupling and load variations. Only one pair of coils is used for both the power link and the bi-directional data link. Except for the secondary coil, the eye implant is fully integrated on chip and is fabricated using UMC (United Microelectronics Corporation, Hsinchu, Taiwan) 0.13 µm complementary metal-oxide-semiconductor (CMOS) process with a size of 1.5 mm × 1.5 mm. The secondary coil is fabricated on a printed circuit board (PCB) with a diameter of only 4.4 mm. After coating with biocompatible silicone, the whole implant has dimensions of 6 mm in diameter with a thickness of less than 1 mm. The whole device can be put onto the sclera and beneath the eye's conjunctiva. System functionality and electrical performance are demonstrated with measurement results.
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Wireless power transfer using reconfigurable resonant regulating (R(3)) rectification suffers from limited range in accommodating varying coupling and loading conditions. A primary-assisted regulation principle is proposed to mitigate these limitations, of which the amplitude of the rectifier input voltage on the secondary side is regulated by accordingly adjusting the voltage amplitude Veq on the primary side. A novel current-sensing method and calibration scheme track Veq on the primary side. A ramp generator simultaneously provides three clock signals for different modules. Both the primary equalizer and the R(3) rectifier are implemented as custom integrated circuits fabricated in a 0.35 µm CMOS process, with the global control implemented in FPGA. Measurements show that with the primary equalizer, the workable coupling and loading ranges are extended by 250% at 120 mW load and 300% at 1.2 cm coil distance compared to the same system without the primary equalizer. A maximum rectifier efficiency of 92.5% and a total system efficiency of 62.4% are demonstrated.
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Tecnología Inalámbrica/instrumentación , Suministros de Energía Eléctrica , Diseño de Equipo , Prótesis e Implantes , Procesamiento de Señales Asistido por ComputadorRESUMEN
The varied NER genes and smoking are two important risk factors of bladder cancer, but the mechanism of the NER protein and smoking in cancer progression, however, remains unclear. In this report, we compared the expressions of NER genes in 79 bladder cancer tissues with or without any recurrence by real-time PCR and then analyzed the varied NER genes by immunochemistry in 219 bladder cancer tissue samples. Based on the clinical data, we analyzed the clinical value of varied NER genes and smoking in 219 bladder cancers by the Kaplan-Meier method and Cox proportional hazards regression. We found the expressions of the NER gene XPF and XPC were significantly lower in bladder cancer tissues with a recurrence compared with those without a recurrence at mRNA level. Also, the patients with the XPF and XPC defect had a statistically significant lower median recurrence-free survival time than those without the XPF and XPC defect, and smoking can make this difference more remarkable. Our results suggest that XPF and XPC expression may be a potential predictive factor for bladder cancer, and smoking can not only influence the recurrence of bladder cancer as a single factor but also aggravate the results of the XPF defect and XPC defect.
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Reparación del ADN/genética , Proteínas de Unión al ADN/genética , Recurrencia Local de Neoplasia/genética , Fumar/genética , Neoplasias de la Vejiga Urinaria/genética , Femenino , Regulación Neoplásica de la Expresión Génica , Estudios de Asociación Genética , Humanos , Inmunohistoquímica , Estimación de Kaplan-Meier , Masculino , Persona de Mediana Edad , Análisis Multivariante , Recurrencia Local de Neoplasia/patología , Modelos de Riesgos Proporcionales , ARN Mensajero/genética , ARN Mensajero/metabolismo , Neoplasias de la Vejiga Urinaria/patologíaRESUMEN
BiOX have been grown on the surface of activated carbon fibers (ACF) as recycled photocatalysts. The analysis results illustrate that electrostatic adsorption plays an important role in the formation of BiOX/ACF composites. The photocatalytic experimental results indicate that BiOX/ACF show excellent cyclic properties and stable performance.
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Upregulation of sphingosine kinase 1 (SPHK1) protein has been reported to be associated with a poor prognosis in a variety of malignant tumors. However, the role of SPHK1 in bladder cancer (BC) has not been thoroughly elucidated. The purpose of this study was to assess SPHK1 expression and to explore its contribution to BC. Real-time quantitative reverse transcriptase-polymerase chain reaction (qRT-PCR) was conducted to detect SPHK1 mRNA expression in 37 pairs of fresh-frozen BC tissues and corresponding noncancerous tissues. Results showed that SPHK1 mRNA expression level in BC tissues was significantly higher than that in corresponding noncancerous tissues. To investigate the association between SPHK1 protein expression and clinicopathological characteristics of BC, immunohistochemistry (IHC) was performed in 153 archived paraffin-embedded BC samples. Interestingly, high SPHK1 expression was significantly associated with histologic grade (P = 0.045) and tumor stage (P < 0.001) of patients with BC. The Kaplan-Meier survival curve showed that patients with high SPHK1 expression had significantly reduced overall 5-year survival rates (P < 0.001). Multivariate Cox regression analysis further suggested that the increased expression of SPHK1 was an independent poor prognostic factor for this disease. In conclusion, our data offer the convincing evidence for the first time that the increased expression of SPHK1 may be involved in the pathogenesis and progression of BC. SPHK1 might be a potential marker to predict the prognosis in BC.
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Biomarcadores de Tumor/análisis , Fosfotransferasas (Aceptor de Grupo Alcohol)/biosíntesis , Neoplasias de la Vejiga Urinaria/enzimología , Neoplasias de la Vejiga Urinaria/mortalidad , Anciano , Femenino , Humanos , Inmunohistoquímica , Estimación de Kaplan-Meier , Masculino , Persona de Mediana Edad , Fosfotransferasas (Aceptor de Grupo Alcohol)/análisis , Pronóstico , Modelos de Riesgos Proporcionales , Reacción en Cadena en Tiempo Real de la Polimerasa , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Neoplasias de la Vejiga Urinaria/patologíaRESUMEN
Stable Ti(3+) self-doped TiO(2) with tunable phase composition and highly efficient visible-light photoactivity (ca. 32.7 times stronger than an undoped sample for ËOH formation) was synthesized via a facile metallic zinc-assisted method. The surface Ti(3+) species can be stabilized by Zn doping, and the photocatalytic selectivity can be regulated by the phase composition.