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Based on dynamic monitoring data on China's population, by using complex networks, spatial analysis and mathematical measurement, this study reveals the spatial characteristics and influencing factors of the network of flows of highly educated talents in the Yangtze River Delta region from the national and local perspectives. In the two perspectives, the network has strong isomorphism and certain differences. The in-flow of highly educated talents from cities with high administrative levels and more developed economies to Shanghai constitutes the core of the entire network. From a national perspective, highly educated talents tend to converge to the Yangtze River Delta region. From a local perspective, it was found that these talents cluster towards a limited number of cities in the region. From both perspectives, the flow network has developed into a "core-periphery" progressive hierarchical structure, with Shanghai becoming the sole core city. There is little difference in the influencing factors of talent mobility from both macro and meso perspectives. Highly educated talents would frequently flow between cities with strong economic development levels, and cities with high education level, scientific and technological level, complete infrastructure, and good aesthetics. However, geographical distance still plays a hindering role in the flow of highly educated talents, and factors such as cultural identity, institutional, and social modality differences among regions also have a certain effect on the flow of these talents.
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The problems of environmental pollution are increasingly severe. Among them, industrial wastewater is one of the primary sources of pollution, so it is essential to deal with wastewater, especially oil and water mixtures. At present, biomimetic materials with special wettability have been proven to be effective in oil-water separation. Compared with three-dimensional (3D) materials, two-dimensional (2D) materials show unique advantages in the preparation of special wettable materials due to their high specific surface area, high porosity, controlled structure, and rich functional group rich on the surface. In this review, we first introduce oil-water mixtures and the common oil-water separation mechanism. Then, the research progress of 2D materials in oil-water separation is presented, including but not limited to their structure, types, preparation principles, and methods. In addition, it is still impossible to prepare 2D materials with large sizes because they are powder-like, which greatly limits the application in oil-water separation. Therefore, we provide here a review of several ways to transform 2D materials into 3D materials. In the end, the challenges encountered by 2D materials in separating oil-water are also clarified to promote future applications.
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In this paper, five grading functional gradient lattice structures with a different density perpendicular to the loading direction were proposed, and the surface morphology, deformation behavior, and compression properties of the functional gradient lattice structures prepared by selective laser melting (SLM) with Ti-6Al-4V as the building material were investigated. The results show that the characteristics of the laser energy distribution of the SLM molding process make the spherical metal powder adhere to the surface of the lattice structure struts, resulting in the actual relative density of the lattice structure being higher than the designed theoretical relative density, but the maximum error does not exceed 3.33%. With the same relative density, all lattice structures with density gradients perpendicular to the loading direction have better mechanical properties than the uniform lattice structure, in particular, the elastic modulus of LF, the yield strength of LINEAR, and the first maximum compression strength of INDEX are 28.99%, 16.77%, and 14.46% higher than that of the UNIFORM. In addition, the energy absorption per unit volume of the INDEX and LINEAR is 38.38% and 48.29% higher, respectively, than that of the UNIFORM. Fracture morphology analysis shows that the fracture morphology of these lattice structures shows dimples and smooth planes, indicating that the lattice structure exhibits a mixed brittle and ductile failure mechanism under compressive loading. Finite element analysis results show that when the loading direction is perpendicular to the density gradient-forming direction, the higher density part of the lattice structure is the main bearing part, and the greater the density difference between the two ends of the lattice structure, the greater the elastic modulus.
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With industry development, the separation of oily wastewater is becoming more critical. Inspired by organisms such as lotus leaves, biomimetic superhydrophobic surfaces with micro-nano structures have shown great potential in this regard. In this work, PDMS/PVDF oil-water separation membranes with designed microstructures were prepared by electrospinning technology. The membrane-forming effect of electrospinning with different ratios of PDMS and PVDF was studied. The study found that membranes with high PDMS content were more likely to form microspheres, and PDMS tended to concentrate on the microspheres. The results also showed that the microspheres would bring better hydrophobicity to the membrane. When the ratio of PDMS to PVDF is 1:2, the membrane has a water contact angle of up to 150° and an oil contact angle of 0°. At this ratio, the separation efficiency of the membrane for the water-in-oil emulsion is 98.7%, and it can still maintain more than 98% after ten separation cycles, which is a good candidate for oil-water separation. Furthermore, microspheres enable the membrane to achieve macroscopic uniformity and microscopic phase separation so that the membranes have both good elongation and fracture strength. In addition, the PDMS/PVDF membranes also exhibit excellent UV resistance, and their UV protection factor is greater than 185, making them a potential UV protective material.
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To optimize the microstructure and properties of TC4 specimens formed by selective laser melting (SLM), the test program of formed specimens by the variable parameter forming process (VPFP) was designed based on the quantitative parameter forming process (QPFP). The purpose of this study is to explore the influence of the VPFP on the surface morphology, tensile properties, and microstructure of the specimens. The test results show that the surface morphology and tensile properties of the specimens were better formed by the VPFP. The internal holes of the specimens formed by the VPFP were small in volume and occupied a relatively small proportion, and the density could reach 99.7%. When the laser power was 300 W-260 W and equally divided into six hierarchies, the tensile strength could reach 1185.214 MPa by VPFP, but the elongation had no obvious change. The number of secondary acicular martensite α' phases was decreased in the microstructure of the specimens formed with VPFP. With the superposition of the hierarchy, the length of the primary acicular martensite α' phase became shorter, the width became larger, and the width of the columnar crystal ß phase became smaller. The VPFP is used to change the inherent method of forming specimens with the same parameters, which provides a new idea for SLM-forming structures; the test provides data and yields a theoretical research basis for forming the specimens process method.
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The Betta fish displays a remarkable variety of phenotypes selected during domestication. However, the genetic basis underlying these traits remains largely unexplored. Here, we report a high-quality genome assembly and resequencing of 727 individuals representing diverse morphotypes of the Betta fish. We show that current breeds have a complex domestication history with extensive introgression with wild species. Using a genome-wide association study, we identify the genetic basis of multiple traits, including coloration patterns, the "Dumbo" phenotype with pectoral fin outgrowth, extraordinary enlargement of body size that we map to a major locus on chromosome 8, the sex determination locus that we map to dmrt1, and the long-fin phenotype that maps to the locus containing kcnj15. We also identify a polygenic signal related to aggression, involving multiple neural system-related genes such as esyt2, apbb2, and pank2. Our study provides a resource for developing the Betta fish as a genetic model for morphological and behavioral research in vertebrates.
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Peixes , Estudo de Associação Genômica Ampla , Agressão , Animais , Peixes/genética , Fenótipo , Análise de Sequência de DNARESUMO
The aim of this study was to improve the functional properties of chickpea protein for its potential application in the food industry. The effects of low frequency high intensity ultrasound (HIU) at different power (0-300 W) and time (15-30 min) on the rheological properties, gelation, thermal stability, solubility and microstructure of chickpea protein were tested and analyzed. Based on the analysis, it was found that HIU caused the disruption of non-covalent bonds between protein chains leading to the unfolding of chickpea. The HIU-treated chickpea isolate protein aggregates were smaller and more uniformly dispersed, with increased orderly structure, thermal stability, and exposure of hydrophobic and charged groups originally buried in the interior. The experimental results also showed that the effect of HIU did not become more pronounced with increasing power and time, as the power exceeding 150 W for 30 min led to the formation of new polymers by the interactions between the exposed non-covalent groups, which were more ordered and homogeneous than those without HIU.
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Cicer , Interações Hidrofóbicas e Hidrofílicas , Reologia , Solubilidade , Ondas UltrassônicasRESUMO
Rudimentary uterine horn pregnancy is a rare and serious type of ectopic pregnancy and is hard to diagnose due to a lack of typical clinical symptoms at the early stage. A 35-year-old woman who was17 weeks pregnant and had a complicated history of infertility came to our hospital complaining of abdominal pain without vaginal bleeding. Computed tomography scan after 12 hours showed that her pregnancy was in the small cavity of a rudimentary uterine horn, which had ruptured. Noncommunicating rudimentary uterine horn pregnancy is an extremely rare form of ectopic gestation, and its diagnosis and management remain challenging. Nevertheless, physician awareness of various forms of unicornuate uteri and rudimentary uterine horn can save lives.
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BACKGROUND: The aim of this study was to evaluate the effectiveness and safety of different treatment strategies for endogenic caesarean scar pregnancy (CSP) patients. METHODS: According to Vial's standard, we defined endogenic-type CSP as (1) the gestational sac growing towards the uterine cavity and (2) a greater than 0.3 cm thickness of myometrial tissue at the caesarean scar. A total of 447 endogenic CSP patients out of 527 patients from 4 medical centres in China were enrolled in this study. A total of 120 patients were treated with methotrexate (MTX) followed by surgery, 106 received ultrasound-guided curettage directly and 221 received curettage combined with hysteroscopy. The clinical information and clinical outcomes of these patients were reviewed. Successful treatment was defined as (1) no additional treatment needed, (2) no retained mass of conception and (3) serum ß subunit of human chorionic gonadotropin (ß-hCG) level returning to a normal level within 4 weeks. The success rate was analysed based on these factors. RESULT: Among 447 patients, no significant difference was observed in baseline characteristics between groups except for foetal heartbeat. The success rate was significantly different (p<0.001) among the three groups. The highest success rate of 95.9% was noted in the hysteroscopy group, and the lowest success rate of 84.0% was noted in the curettage group. In addition, the MTX group reported the longest hospital stay and highest expenses, but the curettage group showed the shortest and lowest expenses, respectively. Nevertheless, no difference in blood loss was observed between the groups. CONCLUSION: The combination of curettage and hysteroscopy represents the most effective strategy. Pretreatment with MTX did not result in better clinical outcomes. Ultrasound-guided curettage directly should not be considered a first-line treatment choice for endogenic CSP patients.
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Cicatriz , Gravidez Ectópica , Cesárea/efeitos adversos , Gonadotropina Coriônica Humana Subunidade beta , Cicatriz/etiologia , Cicatriz/terapia , Feminino , Humanos , Metotrexato/uso terapêutico , Gravidez , Gravidez Ectópica/etiologia , Gravidez Ectópica/terapia , Estudos Retrospectivos , Resultado do TratamentoRESUMO
We describe two new species of Parosphromenus from Indonesia based on morphological and molecular diagnoses. Parosphromenus juelinae, sp. nov., occurs on Bangka Island. Its unpaired fin coloration is similar to that of P. deissneri, but it differs from the latter in having a rounded caudal fin with a non-filamentous branched median ray and a smaller anal fin. Although the new species has the same caudal fin structure as P. bintan, it can be distinguished from the latter by its distinct unpaired fin coloration and the intense red color on the body flanks. Parosphromenus kishii, sp. nov., is found only in a single river system in Kalimantan Tengah. It is distinguished from all other congeners by the unique coloration of its caudal fin. A phylogenetic tree based on the cytochrome b (cytb) gene indicates that the two new species are distinct monophyletic groups constituting distinct phylogenetic branches from their congeners. Cytochrome b Genetic distances between Parosphromenus juelinae, sp. nov., and Parosphromenus kishii, sp. nov., and the other taxa in the phylogenetic tree range from 2.44% to 19.52% and from 8.65% to 17.28%, respectively.
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Peixes , Rios , Animais , Indonésia , FilogeniaRESUMO
BACKGROUND: Citrus fiber is a main component in the peel of citrus and contains natural dietary fiber. It is often used as a functional additive to improve the texture or nutritional property of food. It is also widely used to reduce the content of absorbable fat in sausages and other meat products, and to improve food stability as an emulsifier. In this research, the dynamic rheological properties (linear and non-linear) of citrus peel fiber/corn oil (CF/CO) emulsion system under high pressure homogenization (HPH) treatment was investigated. RESULT: Rheological results illustrated HPH treatment significantly increased the apparent viscosity of the emulsion, reduced the activation energy of the emulsion and distinctly improved the viscoelasticity of the emulsion. Meanwhile, HPH treatment increased the linear viscoelastic region of the sample, and the behavior of the emulsion converted from strain thinning (without HPH treatment) to weak strain overshoot (with HPH treatment). Lissajous curves indicated the viscosity of the sample increased first and then decreased with strain increasing and the third harmonic contributed much more to the first harmonic compared with the fifth harmonic. Chebyshev stress decomposition revealed that, as strain increased, the samples with HPH treatment showed internal-cycle strain hardening behavior first, then turned to internal-cycle softening behavior. CONCLUSION: HPH treatment can significantly improve the processing performance of CF/CO emulsion as well as the stability against large periodic oscillations in food processing. © 2020 Society of Chemical Industry.
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Citrus/química , Óleo de Milho/química , Emulsões/química , Manipulação de Alimentos/métodos , Extratos Vegetais/química , Óleo de Milho/isolamento & purificação , Fibras na Dieta/análise , Emulsões/isolamento & purificação , Manipulação de Alimentos/instrumentação , Extratos Vegetais/isolamento & purificação , Pressão , Reologia , ViscosidadeRESUMO
The selection of anesthetic method and drugs is of utmost importance for patients undergoing caesarean section. The application of anesthetic drugs may affect the immune system of the maternal patient and neonate. Therefore, the present study aimed to analyze the effect of dexmedetomidine combined with lumbar anesthesia on type 1 T-helper cells (Th1) and Th2 cytokines in mothers and their neonates undergoing caesarean section. A total of 60 females with full-term pregnancies and an American Society of Anesthesiologists grade I or II who received caesarean section were selected and equally divided in a randomized manner into a control group receiving lumbar epidural anesthesia and a combination group treated by dexmedetomidine combined with lumbar epidural anesthesia. The visual analogue scale (VAS) score, adverse reactions, traction response and the neonates' Apgar score were compared between the two groups. The levels of interleukin-2 (IL-2), tumor necrosis factor-α (TNF-α), IL-4 and IL-10 in the blood of mothers and neonates were detected by reverse transcription-quantitative PCR and ELISA. The results indicated no statistically significant difference in the Apgar score between the two groups. The VAS scores, adverse reactions, reduced traction response, as well as IL-2 and TNF-α expression, in the mothers of the combination group were significantly decreased, while IL-4 and IL-10 were obviously elevated compared with those in the controls (P<0.05). Furthermore, IL-2 and TNF-α levels were markedly declined, whereas IL-4 and IL-10 expression was apparently enhanced in the neonates from the combination group compared with those in the control group (P<0.05). In conclusion, dexmedetomidine in addition to lumbar epidural anesthesia reduces the VAS score, adverse reactions and traction response, and promotes the conversion of Th1 cytokines to Th2 cytokines in mothers/nonates after caesarean section.
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The aim of this study was to evaluate the effect of the miR-301a/PTEN pathway in cervical cancer. miR-301a and PTEN expression were measured by quantitative real-time PCR (qRT-PCR) in tissues samples and HeLa cells. PTEN protein level was determined by Western blotting. Dual reporter luciferase assay was performed to validate PTEN as a direct target of miR-301a. The gain- and loss-of function assay was performed by miR-301a overexpression and silencing. Cell proliferation was monitored by cell counting Kit-8 (CCK-8). Cell apoptosis was quantitated by flow cytometry. SPSS was used to analyze the significant difference in the treatments. miR-301a demonstrated a significantly higher expression in cervical carcinoma tissues compared with the paired non-carcinoma tissues ( n = 12), while PTEN expression was found to be significantly lower in cervical carcinoma tissues than their paired non-carcinoma tissues ( n = 12). In addition, PTEN was identified as the direct target of miR-301a. Moreover, overexpression of miR-301a significantly promoted HeLa cells proliferation and anti-apoptosis which had a reverse pattern after PTEN overexpression. Our results confirm PTEN as a direct target of miR-301a in HeLa cells and suggest that miR-301a/PTEN pathway contributes to the development and progression of cervical cancer.
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MicroRNAs/genética , PTEN Fosfo-Hidrolase/metabolismo , Neoplasias do Colo do Útero/genética , Apoptose , Carcinogênese , Proliferação de Células , Progressão da Doença , Feminino , Regulação Neoplásica da Expressão Gênica , Células HeLa , Humanos , MicroRNAs/metabolismo , PTEN Fosfo-Hidrolase/genética , RNA Interferente Pequeno/genética , Transdução de SinaisRESUMO
Up to date, the cervical cancer remains to be one of the leading gynecological malignancies worldwide. MicroRNAs (miRNAs) play critical roles in the process of tumor initiation and progression. However, miR-96 has rarely been investigated in human cervical carcinoma. We aimed to investigate the biological function and underlying molecular mechanism of miR-96 in human cervical carcinoma. MiR-96 levels were determined by qRT-PCR. Protein tyrosine phosphatase, non-receptor type 9 (PTPN9) mRNA and protein levels were investigated by qRT-PCR and western blotting. The cellular proliferation in cervical cells was monitored by CyQuant assay. Soft agar assay was employed to determine the tumorigenicity. 3' UTR luciferase assay was used to validate the target gene of miR-96. SPSS was used to analyze statistical significance in different treatment. MiR-96 was dramatically upregulated in human cervical tumor tissues. Overexpression of miR-96 was found to significantly promote the cellular proliferation and tumorigenicity of cervical cells. Furthermore, we showed that PTPN9 was a direct target gene of miR-96 and had opposite effect to those of miR-96 on cervical cells. MiR-96 may promote the cellular proliferation and tumorigenicity of cervical cells by silencing PTPN9. Our study highlights an importantly regulatory role of miR-96 and suggests that an appropriate manipulation of miR-96 may be a new treatment of human cervical carcinoma in the future.
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A 400 W high-power laser was used to fabricate 200-µm-thick Ti-6Al-4V samples to evaluate the effects of small (50 µm) and large (200 µm) beam diameter on density, microstructure and mechanical properties. A series of single-track experiments demonstrated that it was challenging for the small-beam laser to fabricate smooth and defect-free scan tracks. A larger beam diameter efficiently avoided process instability and provided a more stable and uniform melt pool. By increasing the beam diameter, the density of multilayer samples reached 99.95% of the theoretical value, which is much higher than that achieved with the small beam diameter. However, it was difficult to completely eliminate defects due to serious spatter and evaporation. Moreover, all of the generated samples had relatively coarse surfaces. For the large beam diameter of 200 µm, the optimal yield strength, ultimate tensile strength and elongation were 1150 MPa, 1200 MPa and 8.02%, respectively. In comparison, the small beam diameter of 50 µm resulted in values of 1035 MPa, 1100 MPa and 5.91%, respectively. Overall, the large-diameter laser is more suitable for high-power selective laser melting (SLM) technology, especially for thick layers.
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Selective laser melting (SLM) is a potential additive manufacturing (AM) technology. However, the application of SLM was confined due to low efficiency. To improve efficiency, SLM fabrication with a high layer thickness and fine powder was systematically researched, and the void areas and hollow powders can be reduced by using fine powder. Single-track experiments were used to narrow down process parameter windows. Multi-layer fabrication relative density can be reached 99.99% at the exposure time-point distance-hatch space of 120 µs-40 µm-240 µm. Also, the building rate can be up to 12 mm³/s, which is about 3-10 times higher than the previous studies. Three typical defects were found by studying deeply, including the un-melted defect between the molten pools, the micro-pore defect within the molten pool, and the irregular distribution of the splashing phenomenon. Moreover, the microstructure is mostly equiaxed crystals and a small amount of columnar crystals. The averages of ultimate tensile strength, yield strength, and elongation are 625 MPa, 525 MPa, and 39.9%, respectively. As exposure time increased from 80 µs to 200 µs, the grain size is gradually grown up from 0.98 µm to 2.23 µm, the grain aspect ratio is close to 1, and the tensile properties are shown as a downward trend. The tensile properties of high layer thickness fabricated are not significantly different than those with a coarse-powder layer thickness of low in previous research.