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Precise hydrogen sorting from purge gas (H2/N2) and coke gas (H2/CH4), commonly carried out by cryogenic distillation, still suffers from low separation efficiency, high energy consumption, and considerable capital cost. Though still in its infancy, membrane technology offers a potential to achieve more efficient hydrogen purification. In this study, an optimum separation of hydrogen towards both methane and nitrogen via a kinetically-driven mechanism is realized through preferred orientation control of a MOF membrane. Relying on the 0.3 nm-sized window aligned vertical to the substrate, b-oriented Ti-MOF membrane exhibits ultra-high hydrogen selectivity, surpassing the upper bound limit of separating H2/N2 and H2/CH4 gas pairs attained so far by inorganic membranes. This spectacular selectivity is combined with a high H2 permeability owing to the synergistic effect of the 1 nm-sized MOF channel.
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Room temperature (RT) synthesis of high-performance zeolite membranes, which is profound from techno-economic and eco-friendly perspectives, remains a grand challenge. In this work, we pioneered the RT preparation of well-intergrown pure-silica MFI zeolite (Si-MFI) membranes, which was realized through adopting highly reactive NH4F-mediated gel as nutrient during epitaxial growth. Benefiting from the introduction of fluoride anions as mineralizing agent as well as precisely tuned nucleation and growth kinetics at RT, both their grain boundary structure and thickness could be deliberately controlled, resulting in the formation of Si-MFI membranes showing unprecedented n-/i-butane separation factor (96.7) and n-butane permeance (5.16 × 10-7 mol m-2 s-1 Pa-1) in the case of a feed molar ratio of 10/90, which well transcended the state-of-the-art membranes reported in the literature. This RT synthetic protocol was also proven effective for preparing highly b-oriented Si-MFI film, thus showing great promise for the preparation of diverse zeolite membranes with optimized microstructure and superior performance.
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Rational design and engineering of high-performance molecular sieve membranes towards C2 H4 /C2 H6 and flue gas separations remain a grand challenge to date. In this study, through combining pore micro-environment engineering with meso-structure manipulation, highly c-oriented sub-100â nm-thick Cu@NH2 -MIL-125 membrane was successfully prepared. Coordinatively unsaturated Cu ions immobilized in the NH2 -MIL-125 framework enabled high-affinity π-complexation interactions with C2 H4 , resulting in an C2 H4 /C2 H6 selectivity approaching 13.6, which was 9.4â times higher than that of pristine NH2 -MIL-125 membrane; moreover, benefiting from π-complexation interactions between CO2 and Cu(I) sites, our membrane displayed superior CO2 /N2 selectivity of 43.2 with CO2 permeance of 696 GPU, which far surpassed the benchmark of other pure MOF membranes. The above multi-scale structure optimization strategy is anticipated to present opportunities for significantly enhancing the separation performance of diverse molecular sieve membranes.
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Concurrent regulation of crystallographic orientation and thickness of zirconium metal-organic framework (Zr-MOF) membranes is challenging but promising for their performance enhancement. In this study, we pioneered the fabrication of uniform triangular-shaped, 40â nm thick UiO-66 nanosheet (NS) seeds by employing an anisotropic etching strategy. Through innovating confined counter-diffusion-assisted epitaxial growth, highly (111)-oriented 165â nm-thick UiO-66 membrane was prepared. The significant reduction in thickness and diffusion barrier in the framework endowed the membrane with unprecedented CO2 permeance (2070 GPU) as well as high CO2 /N2 selectivity (35.4), which surpassed the performance limits of state-of-the-art polycrystalline MOF membranes. In addition, highly (111)-oriented 180â nm-thick NH2 -UiO-66 membrane showing superb H2 /CO2 separation performance with H2 permeance of 1230 GPU and H2 /CO2 selectivity of 41.3, was prepared with the above synthetic procedure.
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Although having shown great promise for efficient gas separation, relevant study of Ti-MOF membranes remains very scarce, owing to limited Ti source types and uncertain factors which dominate the separation properties. In this work, we pioneered the use of the Ti8 (µ2 -O)8 (OOCC6 H5 )16 cluster as the Ti source of MIL-125 membranes, which led to lower reaction temperature and higher missing-linker number within the framework and therefore, enhanced CO2 /N2 adsorption selectivity. The MIL-125 membrane prepared by combining single-mode microwave heating with tertiary growth displayed an ideal CO2 /N2 selectivity of 38.7, which ranked the highest among all pristine pure MOF membranes measured under comparable conditions. In addition, the ideal H2 /N2 and H2 /CH4 selectivity was as high as 64.9 and 40.7, thus showing great promise for versatile utility in gas separation.
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PURPOSE: Recurrent patella dislocation (RPD) is the most common complication of patellar instability. The effects of different surgical techniques on the outcome of RPD treatments remain unclear. This study was conducted to compare the effects of three surgical techniques in treating RPD by three-dimensional (3D) reconstruction from computed tomography (CT) scans. METHODS: Sixty-eight patients with RPD and no previous surgical treatments who attended our hospital between October 2010 and 2013 were enrolled and randomly assigned into three groups: (1) medial patellofemoral ligament (MPFL) reconstruction and medial patellar retinaculum (MPR) plication group; (2) lateral patellar retinaculum (LPR) release and MPR plication group; and (3) MPFL reconstruction and LPR release group. Knee joints with flexion of 20° were scanned by a 64-row CT scanner and 3D reconstructed. Congruence angle (CA), patellar tilt angle (PTA), lateral patellofemoral angle (LPFA), and congruence of the lateral patellofemoral articular surface were measured. Knee joint function was evaluated by the Lysholm knee scoring scale, Kujala patellofemoral score, and International Knee Documentation Committee (IKDC) score. RESULTS: Pre-operative clinical characteristics were similar across groups. After treatment, the CA, PTA, and LPFA were reverted to normal post-operatively without statistically significant between-group differences. The MPFL reconstruction and LPR release group had the highest congruence of the lateral patellofemoral articular surface; while the (LPR) release and (MPR) plication group had the lowest Lysholm knee scoring scale, Kujala patellofemoral score, and IKDC score after surgery. CONCLUSIONS: The MPFL reconstruction and LPR release group had the best clinical outcomes among the three surgical methods, as indicated by better joint congruence after 3D joint reconstruction and higher knee function scores.
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Articulação do Joelho/cirurgia , Luxação Patelar/cirurgia , Procedimentos de Cirurgia Plástica/métodos , Adolescente , Adulto , Feminino , Humanos , Imageamento Tridimensional/métodos , Instabilidade Articular/cirurgia , Articulação do Joelho/diagnóstico por imagem , Ligamentos Articulares/cirurgia , Masculino , Patela/cirurgia , Luxação Patelar/diagnóstico por imagem , Amplitude de Movimento Articular , Recidiva , Tomografia Computadorizada por Raios X/métodos , Resultado do Tratamento , Adulto JovemRESUMO
OBJECTIVE: To comparatively analyze the dynamic contrast-enhanced (DCE) characteristics and its clinical value between stage-I endometrial carcinomas versus polyps with 3.0T magnetic resonance imaging (MRI). METHODS: A retrospective analysis was performed for DCE-MRI manifestation in 27 patients with histopathologically proved endometrial masses. There were stage-I endometrial carcinomas (n = 14) and polyps (n = 13). The signal intensity of solid component was measured and time-intensity curves (TIC) was obtained. TIC of lesions were divided into 4 subtypes. The time-to-peak (TTP) and signal intensity (SI) were determined from TICs. The arterial phase relative signal increase ratio (ARSIR), maximal relative signal increase ratio (MRSIR), signal enhancement ratio (SER) and signal intensity difference values (D) of each phase were calculated based on TIC curves respectively. RESULTS: The TIC of 14 stage-I endometrial carcinomas included type I (n = 4), type II (n = 6) and type IV (n = 4). The TIC of 13 polyps included type III (n = 3) and type IV (n = 10). The D values in each phase of 14 stage-I endometrial carcinomas were lower than normal muscle layers. There were statistic differences (P < 0.05) of each phase including 32, 48, 64, 109, 154, 199 s. For stage-I endometrial carcinomas, MRSIR and TTP were lower (P < 0.01) than normal muscle layers while SER was higher (P < 0.01) than normal muscle layers . The each phase of D of stage-I endometrial carcinomas were lower than polyps, and there were statistic differences (P < 0.05) of each phase including 32, 48, 64, 109, 154, 199 s. The MRSIR and TTP of stage-I endometrial carcinomas were lower (P < 0.01) than those of polyps while SER was higher (P < 0.01) than polyps. CONCLUSION: DCE-MRI can reflect enhanced features of stage-I endometrial carcinomas and polyps during different phases quantitatively. Parameters of DCE-MR and TIC are helpful in the diagnosis and differential diagnosis of stage-I endometrial carcinomas versus polyps.
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Neoplasias do Endométrio , Imageamento por Ressonância Magnética , Pólipos , Doenças Uterinas , Meios de Contraste , Diagnóstico Diferencial , Feminino , Humanos , Estadiamento de Neoplasias , Estudos RetrospectivosRESUMO
High level dissolved B, which poses risks to human health, has been widely observed in geothermal water. In the Guide Basin, NW China, a series of geothermal water samples along a fault show a wide range of B contents ranging from 3.14 to 8.33â¯mg/L, which are higher than the WHO Guideline value equaling 2.4â¯mg/L in drinking water. To identify the sources and fate of B, we conduct a comprehensive analysis of hydrochemistry and stable isotopes (D, 18O and 11B) of three thermal fields representing three stages of hydrogeochemical evolution (stages I, II and III). From stage I to III, there are trends of increasing mineral dissolution, which is supported by increasing mean reservoir temperature and concentrations of conservative elements (Cl, Na, K, Li and Si). Geothermal water in stage I with meteoric origin and the lowest reservoir temperature has the highest B/Na resulting from silicate dissolution and falls on the mixing line between granitoids and cold water on the plot of δ11B versus 1/B, showing the control of silicate dissolution. However, geothermal water in stage III has lower Ca, B Sr and B/Na than that in stage II. Because of the occurrence of other processes, geothermal water in stages II and III deviates from the LMWL. Compared with geothermal water in stage I, the increased Sr/Ca and decreased B/Ca show that B are removed by both coprecipitation and vapor separation. With the aid of B isotopes, we find vapor separation dominates in stage II, whereas carbonate precipitation dominates in stage III. Overall, a combined use of three isotopes (H, O and B) and three element ratios (B/Na, B/Ca and Sr/Ca) leads to a complete understanding of B cycle and hydrogeochemical evolution in hydrothermal systems.
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Reproductive competence in male mammals depends on testicular function. Testicular development and spermatogenesis in goats involve highly complex physiological processes. In this study, six testes were, respectively, obtained from each age group, immature (1 month), sexually mature (6 months) and physically mature (12 months old) Qianbei Ma goats. RNA-Seq was performed to assess testicular mRNA expression in Qianbei Ma goats at different developmental stages. Totally, 18 libraries were constructed to screen genes and pathways involved in testis development and spermatogenesis. Totally, 9724 upregulated and 4153 downregulated DEGs were found between immature (I) and sexually mature (S) samples; 7 upregulated and 3 downregulated DEGs were found between sexually mature (S) and physically mature (P) samples, and about 4% of the DEGs underwent alternative splicing events between I and S. Select genes were assessed by qRT-PCR, corroborating RNA-Seq findings. The detected genes have key roles in multiple developmental stages of goat testicular development and spermatogenesis. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses were performed to determine differentially expressed genes (DEGs). GO analysis revealed DEGs between S and P contributed to "reproduction process", "channel activity" and "cell periphery part" between I and S, and in "ion transport process", "channel activity" and "transporter complex part". KEGG analysis suggested the involvement of "glycerolipid metabolism", "steroid hormone biosynthesis" and "MAPK signaling pathway" in testis development and spermatogenesis. Genes including IGF1, TGFB1, TGFBR1 and EGFR may control the development of the testis from immature to sexually mature, which might be important candidate genes for the development of goat testis. The current study provides novel insights into goat testicular development and spermatogenesis.
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Testículo , Transcriptoma , Animais , Masculino , Testículo/metabolismo , Cabras/genética , Cabras/metabolismo , Espermatogênese/genética , Perfilação da Expressão GênicaRESUMO
Circular RNAs (circRNAs) play an important role in regulating the mammalian reproductive system, especially testicular development and spermatogenesis. However, their functions in testicular development and spermatogenesis in the Qianbei Ma goat, the Guizhou endemic breed are still unclear. In this study, tissue sectioning and circRNAs transcriptome analysis were conducted to compare the changes of morphology and circular RNAs gene expression profile at four different developmental stages (0Y, 0-month-old; 6Y, 6-month-old; 12Y, 12-month-old; 18Y, 18-month-old). The results showed that the circumferences and area of the seminiferous tubule gradually increased with age, and the lumen of the seminiferous tubule in the testis differentiated significantly. 12,784 circRNAs were detected from testicular tissues at four different developmental stages by RNA sequencing, and 8,140 DEcircRNAs (differentially expressed circRNAs) were found in 0Y vs. 6Y, 6Y vs. 12Y, 12Y vs. 18Y and 0Y vs. 18Y, 0Y vs. 12Y, 6Y vs. 18Y Functional enrichment analysis of the source genes showed that they were mainly enriched in testicular development and spermatogenesis. In addition, the miRNAs and mRNAs associated with DECircRNAs in 6 control groups were predicted by bioinformatics, and 81 highly expressed DECircRNAs and their associated miRNAs and mRNAs were selected to construct the ceRNA network. Through functional enrichment analysis of the target genes of circRNAs in the network, some candidate circRNAs related to testicular development and spermatogenesis were obtained. Such as circRNA_07172, circRNA_04859, circRNA_07832, circRNA_00032 and circRNA_07510. These results will help to reveal the mechanism of circRNAs in testicular development and spermatogenesis, and also provide some guidance for goat reproduction.
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Complete suppression of twin crystal formation in oriented metal-organic framework (MOF) film remains a great challenge. In this study, we successfully avoided the twin generation in c-oriented NH2-MIL-125 film through simple competitive metal ion-based coordination modulation. Simultaneously, relevant mechanism associated with twin suppression was elucidated.
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The purpose of this paper was to investigate the effects of N-acetylcysteine (NAC) on the proliferation, hormone secretion, and mRNA expression profiles of ovarian granulosa cells (GCs) in vitro. A total of 12 ovaries from 6 follicular-stage goats were collected for granulosa cell extraction. The optimum concentration of NAC addition was determined to be 200 µM via the Cell Counting Kit 8 (CCK-8) method. Next, GCs were cultured in a medium supplemented with 200 µM NAC (200 µM NAC group) and 0 µ M NAC (control group) for 48 h. The effects of 200 µM NAC on the proliferation of granulosa cells and hormones were studied by 5-ethynyl-2'-deoxyuridine (EdU) assay and enzyme-linked immunosorbent assay (ELISA). mRNA expression was analyzed by transcriptome sequencing. The results indicate that 200 µM NAC significantly increased cell viability and the proportion of cells in the S phase but promoted hormone secretion to a lesser degree. Overall, 122 differentially expressed genes (DEGs) were identified. A total of 51 upregulated and 71 downregulated genes were included. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analyses indicated that the most DEGs were enriched in terms of cell growth regulation, cell growth, neuroactive ligand-receptor interaction, cytokine-cytokine receptor interaction, the cAMP-signaling pathway, and the Wnt-signaling pathway. Seven genes related to granulosa cell proliferation were screened, IGFBP4, HTRA4, SST, SSTR1, WISP1, DAAM2, and RSPO2. The above results provide molecular theoretical support for NAC as a feed additive to improve follicle development and improve reproductive performance in ewes.
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Acetilcisteína , Transcriptoma , Feminino , Animais , Ovinos , Acetilcisteína/metabolismo , Cabras/genética , Células da Granulosa/metabolismo , Proliferação de Células , Hormônios , RNA Mensageiro/metabolismoRESUMO
N acetylcysteine (NAC) affects antioxidation and reactive oxygen species scavenging in the body and thereby promotes embryonic development and implantation and inhibits inflammation. The mechanism through which NAC regulates reproductive performance in the uteri of goats during early gestation remains unclear. In this study, the treatment group was fed 0.07% NAC for the first 35 days of gestation, whereas the control group received no NAC supplementation. The regulatory genes and key pathways associated with goat reproductive performance under NAC supplementation were identified by RNA-seq. RT-qPCR was used to verify the sequencing results and subsequently construct tissue expression profiles of the relevant genes. RNA-seq identified 19,796 genes coexpressed in the control and treatment groups and 1318 differentially expressed genes (DEGs), including 787 and 531 DEGs enriched in the treatment and control groups, respectively. A GO analysis revealed that the identified genes mapped to pathways such as cell activation, cytokine production, cell mitotic processes, and angiogenesis, and a KEGG enrichment analysis showed that the DEGs were enriched in pathways associated with reproductive regulation, immune regulation, resistance to oxidative stress, and cell adhesion. The RT-qPCR analysis showed that BDNF and CSF-1 were most highly expressed in the uterus, that WIF1 and ESR2 showed low expression in the uterus, and that CTSS, PTX3, and TGFß-3 were most highly expressed in the oviduct, which indicated that these genes may be directly or indirectly involved in the modulation of reproduction in early-gestation goats. These findings provide fundamental data for the NAC-mediated modulation of the reproductive performance of goats during early gestation.
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Zeolite nanosheets have shown unprecedented opportunities for a wide range of applications, yet developing facile methods for fabrication of uniform zeolite nanosheets remains a great challenge. Here, a facile approach involving anisotropic etching with an aqueous solution of tetrapropylammonium hydroxide (TPAOH) was developed for preparing uniform high-aspect ratio hierarchical MFI nanosheets. In addition, the mechanism associated with the formation of MFI nanosheets was proposed. In the next step, a dynamic air-liquid interface-assisted self-assembly method and single-mode microwave heating were used for b-oriented MFI nanosheets monolayer deposition and controlled in-plane solution-based epitaxial growth, respectively, ensuring the formation of well-intergrown b-oriented MFI layers with sub-100-nm thickness. Moreover, our study indicated that b-oriented ultrathin MFI layers could be fabricated on diverse substrates demonstrating excellent anticorrosion capacity, ionic sieving properties, and n-/i-butane isomer separation performance.
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Layered molecular sieve membranes containing uniform interlayer galleries have offered unprecedented opportunities to reach a performance far beyond the Robeson upper bound line. In this study, we took the initiative to prepare layered zirconium phenylphosphonate (ZrPP) molecular sieve membranes with optimized microstructure on tetragonal zirconia (t-ZrO2) buffer layer-modified porous α-Al2O3 substrates by facile in situ hydrothermal growth. Relying on the 3.2 Å-sized gallery height and preferential CO2 adsorption behavior, prepared ZrPP membranes showed exceptional H2/CO2 selectivity (>100) as well as considerable H2 permeability. Furthermore, extraordinary thermal, mechanical, and chemical stability of ZrPP membranes made them potentially attractive for long-term operations under harsh conditions.
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A novel Cs0.33 WO3 /LDHs (CWLDH) composite was synthesized by simple two steps solvothermal method and first investigated as the photocatalyst for tetracycline (TC) and Congo red (CR) degradation under visible light irradiation. The CWLDH heterostructures catalysts were characterized by XRD, UV-Vis, SEM, XPS and BET. The composite CWLDH showed enhanced photocatalytic activity compared with pure Cs0.33 WO3 and NiAl-LDH under identical experimental conditions. The enhanced photocatalytic activity was mainly attributed to the higher visible light-absorbing ability, efficient electron-hole separation and prolonged lifetimes of photogenerated charges. The photocatalyst presented a high photocatalytic activity (92%) at the optimum of CWLDH-3 and initial TC concentration of 40 mg L-1 . Besides, the degradation efficiency of TC is higher than 75% for reused CWLDH after four cycles, demonstrating that it could be used as a potential catalyst with good photocatalytic activity, stability and reusability. According to the experimental results, a possible photocatalytic mechanism of CWLDH was discussed.
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OBJECTIVE: To investigate the value of MRI follow-up in pediatric patients with spinal tuberculosis. METHODS: From February 2004 to April 2013, MRI imaging data in 21 children with spinal tuberculosis by pathologically and clinically proven were retrospectively analysed. There were 11 males and 10 males, with an average age of 9.4 years old ranging from 2 to 14 years old. Eighteen patients were received conservative treatment, 3 patients were treated by surgical operation. The course of disease ranged from 2 months to 3 years. All cases underwent two or more MRI examinations for follow-up. MRI findings of the first and second examination were comparatively analyzed,including signal changes of vertebral body and intervertebral, paraspinal abscess and the change of kyphosis angle. RESULTS: In the 21 cases with tuberculosis, 85 vertebral bodies were affected in total, including 10.6%(9/85), 49.4%(42/85) and 40%(34/85) vertebral bodies separately in the cervical,thoracic, lumbosacral spine. Follow-up MRI showed vertebral body shape and signal had no obvious change during or after treatment, 15 cases with vertebral bodies changed flat or cuneate, 10 cases with disc involvement,and intervertebral space became narrowing at different level. Among 13 patients with kyphosis angle greater than 0°, 7 were located on thoracic, 2, 3, 1 were on thoracolumbar, lumbar and cervical spine, respectively. Among 18 cases with conservative treatment,kyphosis angle were 0° on the first and the follow up MRI of 8 patients. One case of mild (<10°) kyphosis,follow-up MRI during therapy showed the angle slightly increased; 5 cases with moderate (10° to 30°), follow-up MRI during therapy showed no obvious change; 4 cases with severe (>30°), follow-up MRI during and after therapy showed kyphosis increased in varying degrees. CONCLUSION: Follow-up MRI can make a big difference in the spinal tuberculosis of children; it can clearly show the change of the vertebral body and intervertebral space, paraspinal abscess and the kyphosis angle after the treatment,which can provide reference for clinical treatment and estimating prognosis.