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Understanding the promotional effects of trace doped Zn in co/Nc for efficient one-pot catalytic conversion of furfural to 2-methyl-tetrahydrofuran

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Journal of Energy chemistry 2022年第8期31卷 225-233,I0007页

作者： lei Huang liqiang Wang Zonghao Zhang Xinpeng Guo Xiaowen Zhang johnny Muya chabu Pingle liu Feiying Tang college of chemical Engineering Xiangtan UniversityXiangtan 411105HunanChina Henan Province Industrial Technology Research Institute of Resources and Materials School of Material Science and EngineeringZhengzhou UniversityZhengzhou 450001HenanChina Department of chemistry Faculty of ScienceUniversity of LubumbashiPO Box 1825LubumbashiDRCongo Foshan Green Intelligent Manufacturing Research Institute of Xiangtan University Foshan 528010GuangdongChina

2-methyl-tetrahydrofuran(2-MTHF)is a promising biofuel or fuel additive with excellent burning property,a versatile new-style solvent in organic synthesis,and an important medical *** this work,a one-pot selective conversion of furfural(FA)into 2-MTHF was carried out over Zn doped co/Nc *** Zn-co/Nc-1 catalyst with trace Zn dopant(0.38 wt%)exhibited the best performance(yield of 2-MTHF:93.8%).According to the characterizations,it was found that the Zn not only incorporates into the carbon support but also partially dopes into co ***,theoretical calculations demonstrated that the doping of Zn in carbon support can effectively enhance the electron transfer from the support to the metallic co particle,leading to the electron-rich co *** presence of Zn was found to promote the dissociation of hydrogen and to lower the diffusion barrier of hydrogen atom,in favor of the hydrogenation/hydrodeoxygenation ***,the Zn doped models exhibit much lower barrier in breaking c–OH bond of FOl,resulting in higher activity for hydrodeoxygenation of *** theoretical results are consistent with the in situ FT-IR analysis of adsorption substrates and intermediates over Zn doped *** work reveals the mechanism of dopant Zn tailoring the electronic structure and catalytic performance of active sites,providing a deep insight into the design of economical and high-performance catalysts for hydrogenation/hydrodeoxygenation of biomass feedstocks.

关键词： Zn-doping Enhanced electron transfer Biomass upgrade Furfural 2-Methyl-tetrahydrofuran

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High-performance photodetectors based on two-dimensional perovskite crystals with alternating interlayer cations

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Journal of Materiomics 2023年第4期9卷 817-823页

作者： Yezhan li Zhengxun lai You Meng Wei Wang Yuxuan Zhang Xuwen Zhao Di Yin Weijun Wang Pengshan Xie Quan Quan SenPo Yip johnny c.Ho Department of Materials Science and Engineering City University of Hong Kong999077Hong Kong SARChina Institute for Materials chemistry and Engineering Kyushu UniversityFukuoka816-8580Japan State Key laboratory of Terahertz and Millimeter Waves City University of Hong Kong999077Hong Kong SARChina

Organic-inorganic halide perovskite,as a low-cost,solution-processable material with remarkable optoelectronic properties,is ideal candidate to fabricate high-performance photodetectors and is expected to significantly reduce device *** to the common Dion-Jacobson and Ruddlesden-Popper two-dimensional(2D)layered hybrid perovskite compounds,the perovskites with alternating cations in the interlayer(AcI)phase show higher crystal symmetry and narrower optical bandgaps,which exhibit great potential for excellent photodetection ***,we report a high-performance photodetector based on the 2D bilayered hybrid lead halide perovskite single crystal with the AcI phase(GAMA_(2)Pb_(2)I_(7);GA=c(NH_(2))_(3)and MA=cH_(3)NH_(3)).The single-crystal photodetector exhibits high photoresponsivity of 1.56,2.54,and 2.60 A/W for incident light wavelengths of 405,532,and 635 nm under 9.82 nW,respectively,together with the correspondingly high detectivity values of 1.86×10^(12),3.04×10^(12),and 3.11×10^(12)Jones under the same operating ***,a high-resolution imaging sensor is built based on the GAMA_(2)Pb_(2)I_(7)single-crystal photodetector,confirming the high stability and photosensitivity of the imaging *** results show that the 2D hybrid lead halide perovskites with alternating interlayer cations are promising for high-performance visible light photodetectors and imaging systems.

关键词： Photodetector Two-dimensional Hybrid perovskite Alternating interlayer cation Imaging

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Hepatocellular carcinoma masquerading as a bleeding gastric ulcer: A case report and a review of the surgical management

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World Journal of Gastroenterology 2007年第33期13卷 4523-4525页

作者： johnny cA Ong Pierce KH chow Weng-Hoong chan Alex YF chung choon Hua Thng Wai-Keong Wong Department of General Surgery Singapore General Hospital Singapore 169608 Singapore Department of Oncologic Radiology National Cancer Centre Singapore Singapore

Hepatocellular carcinoma (Hcc) is a common malignancyworldwide. While bleeding from the gastrointestinal tract(BGIT) has a well known association with Hcc, suchcases are mainly due to gastric and esophageal *** as a result of invasion of the gastrointestinal tractby Hcc is extremely rare and is reportedly associatedwith very poor prognosis. We describe a 67-year-oldmale who presented with BGIT. Endoscopy showed thesite of bleeding to be from a gastric ulcer, but endoscopictherapy failed to control the bleeding and emergencysurgery was required. At surgery, the ulcer was found tohave arisen from direct invasion of the gastrointestinaltract by Hcc of the left lobe. control of the bleedingwas achieved by surgical resection of the Hcc en-bloc with the lesser curve of the stomach. The patientremains alive 33 mo after surgery. Direct invasion of thegastrointestinal tract by Hcc giving rise to BGIT is veryuncommon. Surgical resection may offer significantlybetter survival over non-surgical therapy, especially if thepatient is a good surgical candidate and has adequatefunctional liver reserves. Prognosis is not uniformly grave.

关键词： Hepatocellular carcinoma Gastrointestinal bleeding Stomach invasion Hepatectomy

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Identification and characterization of chondrogenic progenitor cells in the fascia of postnatal skeletal muscle

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分子细胞生物学报:英文版 2011年第6期3卷 369-377页

作者： Guangheng li Bo Zheng laura B.Meszaros Joseph B.Vella Arvydas Usas Tomoyuki Matsumoto johnny Huard Stem cell Research center Department of Orthopaedic SurgeryUniversity of Pittsburgh450 Technology Drive Suite 206PittsburghPA 15219USA Pediatric cancer Biological Program Department of PediatricsOregon Health and Science UniversityPortlandOR 97239USA Department of Bioengineering University of PittsburghPittsburghPA 15219USA Department of Molecular Genetics and Biochemistry University of PittsburghPittsburghPA 15219USA

Intramuscular injection of bone morphogenetic proteins(BMPs)has been shown to induce ectopic bone formation.A chondrogenic phase is typically observed in this process,which suggests that there may exist a chondrogenic subpopulation of cells residing in skeletal *** prospective cell populations were isolated from rat skeletal muscle:fascia-derived cells(FDcs),extracted from gluteus maximus muscle fascia(epimysium)and muscle-derived cells(MDcs)isolated from the muscle *** populations were investigated for their cell surface marker profiles(flowcytometry analysis),proliferation rates as well as their myogenic and chondrogenic *** majority of FDcs expressed mesenchymal stromal cell markers but not endothelial cell *** underwent chondrogenic differentiation after BMP4 treatment in vitro,but not myogenic *** MDcs showed chondrogenic potential,they expressed the myogenic cell marker desmin and readily underwent myogenic differentiation in vitro;however,the chondrogenic potential of the MDcs is confounded by the presence of FDc-like cells residing in the muscle perimysium and *** clarify the role of the muscle-derived myogenic cells in chondrogenesis,mixed pellets with varying ratios of FDcs and l6 myoblasts were formed and studied for chondrogenic *** results indicated that the chondrogenic potential of the mixed pellets decreased with the increased ratio of myogenic cells to FDcs supporting the role of FDcs in chondro*** together,our results suggest that non-myogenic cells residing in the fascia of skeletal muscle have a strong chondrogenic potential and may represent a novel donor cell source for cartilage regeneration and repair.

关键词： skeletal muscle fascia chondrocytes cartilage

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Targeting small GTPases:emerging grasps on previously untamable *** by KRAS

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Signal Transduction and Targeted Therapy 2023年第6期8卷 2856-2894页

作者： Guowei Yin Jing Huang johnny Petela Hongmei Jiang Yuetong Zhang Siqi Gong Jiaxin Wu Bei liu Jianyou Shi Yijun Gao The Seventh Affiliated Hospital of Sun Yat-sen University Shenzhen518107China State Key laboratory of Oncology in South china Guangdong Key Laboratory of Nasopharyngeal Carcinoma Diagnosis and TherapySun Yat-sen University Cancer CenterGuangzhou510060China Wake Forest University School of Medicine Winston-SalemNC27101USA School of Medicine Sun Yat-Sen UniversityShenzhen518107China National Biomedical Imaging center School of Future TechnologyPeking UniversityBeijing100871China Department of Pharmacy Personalized Drug Therapy Key Laboratory of Sichuan ProvinceSichuan Academy of Medical Sciences&Sichuan Provincial People’s HospitalSchool of MedicineUniversity of Electronic Science and TechnologyChengdu610072China

Small GTPases including Ras,Rho,Rab,Arf,and Ran are omnipresent molecular switches in regulating key cellular *** dysregulation is a therapeutic target for tumors,neurodegeneration,cardiomyopathies,and ***,small GTPases have been historically recognized as“undruggable”.Targeting KRAS,one of the most frequently mutated oncogenes,has only come into reality in the last decade due to the development of breakthrough strategies such as fragment-based screening,covalent ligands,macromolecule inhibitors,and *** KRAS^(G12c)covalent inhibitors have obtained accelerated approval for treating KRAS^(G12c)mutant lung cancer,and allele-specific hotspot mutations on G12D/S/R have been demonstrated as viable *** methods of targeting KRAS are quickly evolving,including transcription,immunogenic neoepitopes,and combinatory targeting with ***,the vast majority of small GTPases and hotspot mutations remain elusive,and clinical resistance to G12c inhibitors poses new *** this article,we summarize diversified biological functions,shared structural properties,and complex regulatory mechanisms of small GTPases and their relationships with human ***,we review the status of drug discovery for targeting small GTPases and the most recent strategic progress focused on targeting *** discovery of new regulatory mechanisms and development of targeting approaches will together promote drug discovery for small GTPases.

关键词： KRAS Targeting breakthrough

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B级王者 SVW Passat lingyu VS Nissan Teana

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世界汽车 2006年第2期 60-67页

作者：何亦亮 johnny Ho

为什么会把领驭和天籁拿到一起做对比?首先,它们都是B级“怪胎”,有着接近c级车的身形,无疑是B级车中的王者;其次,它们有着相近的价格,在经济水平左右一切的时代,价格区间无疑是车型选择最重要的一个标准;再次,它们是大众和日产的“当... 详细信息

为什么会把领驭和天籁拿到一起做对比?首先,它们都是B级“怪胎”,有着接近c级车的身形,无疑是B级车中的王者;其次,它们有着相近的价格,在经济水平左右一切的时代,价格区间无疑是车型选择最重要的一个标准;再次,它们是大众和日产的“当家”车型。分别是帕萨特B5的改款和风度的后继车型,在国际市场上也算主要的竞争对手,并且是该车级中十分热门的车型;最后,因为1.8T和2.3自然吸气发动机在动力输出上十分相近。

关键词： Passat Nissan B级市场需求量 VS 本田雅阁马自达6 消费市场丰田佳美车型

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Development of a Fast and Facile Analytical Approach to Quantify Radiometabolites in Human Plasma Samples Using Ultra High Performance liquid chromatography

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American Journal of Analytical chemistry 2019年第5期10卷 185-201页

作者： cé cile Malherbe Rudy Bidault claude Netter Denis Guilloteau johnny Vercouillie Nicolas Arlicot UMR 1253 iBrain Universit&#233 de Tours Inserm Tours France cHRU de Tours Unit&#233 de Radiopharmacie Tours France Thermo Fisher Scientific Waltham MA USA cHRU de Tours Service de M&#233 decine Nuclé aire in Vitro Tours France INSERM cIc 1415 University Hospital Tours France

Introduction: conventional metabolite analyses often require manual sample preparation, generating variability of measurements. This study describes a new method to quantify radiometabolites in blood, combining ultra high performance liquid chromatography (UHPlc) and turbulent flow chromatography, an alternative fully automated process allowing analyte’s extraction. Methods: A new radiotracer for dopamine transporter imaging, namely lBT-999, was used to demonstrate the method’s robustness. Matrix effect, Turboflow column loading, linearity, specificity and precision were evaluated with in vitro samples of lBT-999 in human plasma. Radiodetector sensitivity and preliminary evaluation were respectively determined by analysis of calibrated samples of [18F]lBT-999 and blood samples from 4 healthy subjects injected with [18F]lBT-999, withdrawn at 5, 15, 30 and 45 min pi. Results: With three sequential loadings (3 × 100 μl) of the Turboflow column, mean coefficients of variation were 1%, below 2%, 2% and 30.9% for matrix effect, specificity, repeatability and intermediate precision, respectively. correlation coefficients for linearity were superior to 0.97. limits of detection and quantification of the radiodetector were fixed at 3 and 9 c/s. Retention times for [18F]lBT-999 and the two radiometabolites detected by radio-UHPlc were 6.5, 4.8 and 9.6 min. Forty-five min after the injection, parent fraction was still predominant with 57.8% ± 25% of the total radioactivity. conclusions: An innovative approach, allying UHPlc and Turboflow column, was developed and its sensitivity, linearity, specificity and repeatability validated. Preliminary results of the clinical trial are in accordance with literature data, demonstrating its efficiency in radiometabolites quantification.

关键词： Radiometabolite Ultra High Performance liquid chromatography Turboflow Method Validation [18F]lBT-999

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提高微型气体传感器可靠性的有效方法-解决氧化锡敏感膜龟裂问题

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测试技术学报 2002年第Z2期16卷 947-952页

作者：闫桂珍 Philip c.H.chan johnny K.O.Sin I-Ming Hsing 北京大学微电子学研究所北京100871 香港科技大学电机与电子工程系香港香港科技大学电机与电子工程系香港香港科技大学电机与电子工程系香港

本文报导了一种解决氧化锡气体敏感膜龟裂问题的有效方法.实验中发现,溅射形成的氧化锡薄膜在高温处理后或在长时间的高温工作中会发生龟裂,对器件的稳定性和可靠性带来很大影响.我们用两种方法解决了这个问题.一个是用磷硅玻璃(PSG)回... 详细信息

本文报导了一种解决氧化锡气体敏感膜龟裂问题的有效方法.实验中发现,溅射形成的氧化锡薄膜在高温处理后或在长时间的高温工作中会发生龟裂,对器件的稳定性和可靠性带来很大影响.我们用两种方法解决了这个问题.一个是用磷硅玻璃(PSG)回流对氧化锡衬底的粗糙表面进行平坦化处理,另一个是把氧化锡薄膜图形设计成许多细长条状,以释放高温引起的应力变化.这种技术也适用于其它薄膜产生的微裂问题.

关键词：微机械气体传感器稳定性 SnO2 龟裂.

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land-Use change on Soil c and N Stocks in the Humid Savannah Agro-Ecological Zone of Ghana

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Journal of Environmental Protection 2022年第1期13卷 32-68页

作者： johnny Kofi Awoonor Fowzia Adiyah Bright Fafali Dogbey Soil Genesis Survey and Classification Division CSIR-Soil Research Institute Kumasi Ghana Department of Soil Science and Agrochemistry Hungarian University of Agriculture and Life Sciences G&ouml d&ouml ll&odblac Hungary Department of Soil Resources Management CSIR College of Science and Technology Accra Ghana

land-use conversion and unsustainable farming practices are degrading native forest ecosystems of Ghana’s humid savannah agro-ecological zone. This study assessed the impact of land-use change on soil c and N stocks in different land-use systems and soil types. A total of eighty (80) composite soil samples at two depths (0 - 20 cm and 20 - 50 cm) were sampled from five land use types (Forest, Woodland savannah, Grassland, Fallow and cropland) for laboratory analyses. Particle size distribution, bulk density, pH, SOc and TN were determined using standard procedures. Results of the study indicated that c and N stocks were significantly lower in croplands (p compared to other land-use systems. There were significant interactions (p land-use systems, soil types, and soil depth for soil c and N stocks. Acrisol and associated soils had the highest c and N stocks. A strong positive significant correlation (p c and N stocks with an R2 value of 0.85 and 0.93 for the 0 - 20 and 20 - 50 cm depth, respectively. Soil c and N stocks in the study area were estimated to be 34.56 kg/m2 and 4.63 kg/m2 for soil types and 26.89 kg/m2 and 3.39 kg/m2 for land use types, respectively for the 0 to 50 cm soil depth. Our findings indicated that the conversion of native forest to arable land has significantly reduced soil c and N stocks in the top 50 cm (0.50 m) soil layer by 50.77% and 47.77%, respectively. Therefore, we conclude that land-use change, soil type, and soil depth influenced soil c and N stocks of land-use systems in the humid savannah agro-ecological zone of Ghana.

关键词： land conversion Nutrient Dynamics Soil c and N Stocks Soil Type land-Use

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Global Stability in Dynamical Systems with Multiple Feedback Mechanisms

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Advances in Pure Mathematics 2016年第5期6卷 393-407页

作者： Morten Andersen Frank Vinther johnny T. Ottesen Department of Science and Environment Roskilde University Roskilde Denmark

A class of n-dimensional ODEs with up to n feedbacks from the n’th variable is analysed. The feedbacks are represented by non-specific, bounded, non-negative c1 functions. The main result is the formulation and proof of an easily applicable criterion for existence of a globally stable fixed point of the system. The proof relies on the contraction mapping theorem. Applications of this type of systems are numerous in biology, e.g., models of the hypothalamic-pituitary-adrenal axis and testosterone secretion. Some results important for modelling are: 1) Existence of an attractive trapping region. This is a bounded set with non-negative elements where solutions cannot escape. All solutions are shown to converge to a “minimal” trapping region. 2) At least one fixed point exists. 3) Sufficient criteria for a unique fixed point are formulated. One case where this is fulfilled is when the feedbacks are negative.

关键词： Odes Multiple Feedbacks Stability Global Stability Attracting Trapping Region Nonlinear Dynamics

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