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中国检验检测 1986年第1期 45-48+35页

作者： r.j.lewandowski 王明冲

高性能合成信号发生器产生编程频率信号,其电平的大小也受数字可编程微调控制,并配有可编程步级衰减器,每一跳步的大小等于微调控制范围。本文所述的自动测试系统利

关键词：信号发生器 dBm 自动测试系统电压比不确定度信号源发射机双平衡混频器电平中频放大器比率变压器中频衰减器射频衰减器

经导管动脉灌注MrI肿瘤灌注减低对预测肝细胞癌化疗栓塞术后非移植生存期的潜在价值

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国际医学放射学杂志 2014年第5期 488-489页

作者： D.Wang r.C.Gaba B.jin r.j.lewandowski A.riaz K.Memon 方晓堃 Department of radiology and radiological Sciences School of medicineVanderbilt University1161 21st Ave SouthMedical Center NorthSuite CCC-1106NashvilleTN 37232-2675

摘要目的研究经导管动脉灌注Mr成像测量手术无法切除的肝细胞癌病人动脉内化疗栓塞期间的灌注变化对非移植生存期的预测价值。材料与方法该项前瞻性研究符

关键词：化疗栓塞肝细胞癌动脉灌注经导管生存期

Dietary fibre effects and the interplay with exogenous carbohydrases in poultry nutrition

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Animal Nutrition 2024年第1期16卷 231-240页

作者： Michael r.Bedford Birger Svihus Aaron j.Cowieson AB Vista Feed Ingredients Ltd Norwegian University of Life Sciences DSM Nutritional Products

A comprehensive understanding of the role of dietary fibre in non-ruminant animal production is elusive. Equivocal and conflated definitions of fibre coupled with significant analytical complexity,interact with poorly defined host and microbiome relationships. Dietary fibre is known to influence gut development, feed intake and passage rate, nutrient absorption, microbiome taxonomy and function, gut p H, endogenous nutrient loss, environmental sustainability, animal welfare and more. Whilst significant gaps persist in our understanding of fibre in non-ruminant animal production, there is substantial interest in optimizing the fibre fraction of feed to induce high value phenotypes such as improved welfare,live performance and to reduce the environmental footprint of animal production systems. In order to achieve these aspirational goals, it is important to tackle dietary fibre with the same level of scrutiny as is currently done for other critical nutrient classes such as protein, minerals and vitamins. The chemical,mechanical and nutritional role of fibre must be explored at the level of monomeric sugars, oligosaccharides and polysaccharides of varying molecular weight and decoration, and this must be in parallel to standardisation of analytical tools and definitions for speciation. To further complicate subject, exogenous carbohydrases recognise dietary fibre as a focal substrate and have varying capacity to generate lower molecular weight carbohydrates that interact differentially with the host and the enteric microbiome. This short review article will explore the interactive space between dietary fibre and exogenous carbohydrases and will include their nutritional and health effects with emphasis on functional development of the gut, microbiome modulation and host metabolism.

关键词： Fibre Carbohydrase Nutrition Microbiome Gastro-intestinal development Feed

Stable diffusion gradients in microfluidic conduits bounded by fluid walls

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Microsystems & Nanoengineering 2024年第3期10卷 357-367页

作者： Federico Nebuloni Cyril Deroy Peter r.Cook Edmond j.Walsh Department of Engineering Science Osney Thermo-Fluids InstituteUniversity of OxfordOxford OX20ESUK Sir William Dunn School of Pathology University of OxfordOxford OX13REUK

Assays mimicking in vitro the concentration gradients triggering biological responses like those involved in fighting infections and blood clotting are essential for biomedical *** assays prove especially attractive as they allow precise control of gradient shape allied to a reduction in *** microfluidic devices are fabricated using solid plastics that prevent direct access to responding ***-walled microfluidics allows the manufacture of circuits on standard Petri dishes in seconds,coupled to simple operating methods;cell-culture medium sitting in a standard dish is confined to circuits by fluid walls made of an immiscible *** develop and experimentally validate an analytical model of diffusion between two or more aqueous streams flowing at different rates into a fluid-walled conduit with the cross-section of a circular *** solid walls,fluid walls morph during flows as pressures fall,with wall shape changing down the *** model is validated experimentally for Fourier numbersrescein diffusing between laminar *** enables a priori prediction of concentration gradients throughout a conduit,so allowing rapid circuit design as well as providing bioscientists with an accurate way of predicting local concentrations of bioactive molecules around responsive and nonresponsive cells.

关键词： walls diffusion attractive

Single-atom Pt on carbon nanotubes for selective electrocatalysis

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Carbon Energy 2024年第1期6卷 63-71页

作者： Samuel S.Hardisty Xiaoqian Lin Anthony r.j.Kucernak David Zitoun Department of Chemistry Bar Ilan Institute of Nanotechnology and Advanced Materials(BINA)Bar Ilan UniversityRamat GanIsrael Department of Chemistry Molecular Science Research HubImperial College LondonLondonUK

Utilizing supported single atoms as catalysts presents an opportunity to reduce the usage of critical raw materials such as platinum,which are essential for electrochemical reactions such as hydrogen oxidation reaction(HOr).Herein,we describe the synthesis of a Pt single electrocatalyst inside single-walled carbon nanotubes(SWCNTs)via a redox *** via electron microscopy,X-ray photoelectron microscopy,and X-ray absorption spectroscopy show the single-atom nature of the *** electrochemical behavior of the sample to hydrogen and oxygen was investigated using the advanced floating electrode technique,which minimizes mass transport limitations and gives a thorough insight into the activity of the *** single-atom samples showed higher HOr activity than state-of-the-art 30%Pt/C while almost no oxygen reduction reaction activity in the proton exchange membrane fuel cell operating *** selective activity toward HOr arose as the main fingerprint of the catalyst confinement in the SWCNTs.

关键词： confinement electrocatalysis hydrogen platinum single atom catalysts

放射性肝段切除术:早期肝癌的潜在性根治疗法

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国际医学放射学杂志 2018年第4期 485-485页

作者： r.j.lewandowski A.Gabr N.Abouchaleh r.Ali A.A.Asadi r.A.Mora 朱静 Department of radiology Section of Interventional RadiologyNorthwestern Memorial HospitalRobert H. Lurie Comprehensive Cancer Center

目的探究早期肝细胞癌(HCC)放射性肝段切除术(rS)的远期疗效。针对直径不超过5 cm的孤立性HCC且欲保留肝功能的病人,比较rS的远期疗效与根治疗法疗效是否存在差异。材料与方法回顾性纳入2003年—2016年期间的孤立性HCC病人(年龄22～96岁... 详细信息

目的探究早期肝细胞癌(HCC)放射性肝段切除术(rS)的远期疗效。针对直径不超过5 cm的孤立性HCC且欲保留肝功能的病人,比较rS的远期疗效与根治疗法疗效是否存在差异。材料与方法回顾性纳入2003年—2016年期间的孤立性HCC病人(年龄22～96岁,中位年龄71岁)。病人肿瘤大小均不超过5 cm,且进行rS(剂量为190 Gy)治疗,而未进行经皮消融治疗。排除后续接受治疗性肝移植的病人以消除影响生存的混杂因素,最终纳入70例病人。根据欧洲肝脏研究协会(EASL)与世界卫生组织(WHO)的指南,使用Kaplan Meier法评估病人经rS治疗后的进展时间和总生存期中位数。结果 70例病人经rS治疗随访长达14年以上。其中63例(90%)经EASL标准评价,有41例(59%)显示完全缓解。50例(71%)经WHO标准评价,有11例(16%)取得完全缓解。采用EASL和WHO标准,6个月的反应率分别为86%和49%。中位进展时间为2.4年(95%CI:2.1～5.7),72%的病人在5年内没有靶病变进展。总生存期中位数为6.7年(95%CI:3.1～6.7);1、3、5年的生存率分别为98%、66%和57%。1、3、5年总生存率分别为100%、82%和75%。直径不超过3 cm的肿瘤(n=45)病人总生存率显著大于3 cm以上的肿瘤病人(P=0.026)。结论在早期原发性肝细胞癌肝功能保留的病人中,rS治疗在肿瘤反应率、肿瘤控制和生存率与根治性治疗具有可比性。

关键词：肝段切除术肝功能远期疗效 rS 放射性 HCC 进展时间

Mathematical modelling of ball and plate system with experimental and correlation function-based model validation

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Control Theory and Technology 2024年第2期22卷 326-341页

作者： T.r.Dil Kumar S.j.Mija Department of Electrical Engineering National Institute of Technology CalicutKozhikode673601KeralaIndia

The ball and plate system is an inherently nonlinear under actuated benchmark system used for validating the performance of various control schemes. A mathematical model depicting the dynamics close to that of the system is very much required for such a test bed. In this correspondence, the complete nonlinear model, a simplified nonlinear model, and a linearized model of the ball and plate system are developed. The system comprises a ball and plate mechanism and a rotary servo unit. The ball and plate mechanism is modelled using the Euler–Lagrange method, whereas the rotary servo subsystem is modelled from the first principles. The nonlinear model of the combined system is developed by including the dynamics of the servo motor with gear and rolling resistance between the ball and the plate. The simplified nonlinear model of the system is obtained with suitable assumptions. The model is linearized around the operating point using the jacobian. The validity of the developed models is investigated through correlation function analysis. The open-loop response of the three models, viz., nonlinear, simplified nonlinear, and linearized models, is analyzed in the MATLAB/Simulink platform. Since the open-loop system is unstable, the experimental validation of the model is performed with a double-loop PSO (particle swarm optimization) PID control scheme.

关键词： Ball and plate system Correlation function Model validation Particle swarm optimization(PSO) PSO PID controller

Analysis of mid-spatial frequency wavefront distortions from a liquid-cooled flash-lamp pumped Nd:phosphate laser amplifier

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High Power Laser Science and Engineering 2024年第1期12卷 24-29页

作者： Pierre-Marie Dalbies Sandy Cavaro Edouard Bordenave Nathalie Blanchot julien G.Moreau jérôme Neauport CEA CESTA Le BarpFrance

Mid-spatial frequency wavefront deformation can be deleterious for the operation of high-energy laser systems. When fluid cooled high-repetition-rate amplifiers are used, the coolant flow is likely to induce such detrimental mid-spatial frequency wavefront deformations. Here, we describe the design and performance of a 90 mm × 90 mm aperture, liquid-cooled Nd:phosphate split-slab laser amplifier pumped by flash-lamps. The performance of the system is evaluated in terms of wavefront aberration and gain at repetition rates down to 1 shot per minute. The results show that this single cooled split-slab system exhibits low wavefront distortions in the medium to large period range, compatible with a focus on target, and despite the use of liquid coolant traversed by both pump and amplified wavelengths. This makes it a potential candidate for applications in large high-energy laser facilities.

关键词： flash-lamp pumping high-power laser laser cooling neodymium glass wavefront error

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Management of monogenic diabetes in pregnancy:A narrative review

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World journal of Diabetes 2024年第1期15卷 15-23页

作者： Mohammad Sadiq jeeyavudeen Sarah r Murray Mark W j Strachan Metabolic Unit Western General HospitalEdinburgh EH42XUUnited Kingdom MrC Centre for reproductive Health University of Edinburgh Queen’s Medical Research InstituteEdinburgh EH164TJUnited Kingdom

Pregnancy in women with monogenic diabetes is potentially complex,with significant implications for both maternal and fetal *** these,maturity-onset diabetes of the young(MODY)stands out as a prevalent monogenic diabetes subtype frequently encountered in clinical *** subtype of MODY requires a distinct approach tailored to the pregnancy,diverging from management strategies in non-pregnant *** MODY(GCK-MODY)typically does not require treatment outside of pregnancy,but special considerations arise when a woman with GCK-MODY becomes *** glycemic targets in GCK-MODY pregnancies are not exclusively dictated by the maternal/paternal MODY genotype but are also influenced by the genotype of the developing *** pregnancy,the choice between sulfonylurea or insulin for treating hepatocyte nuclear factor 1-alpha(HNF1A)-MODY and HNF4A-MODY depends on the mother’s specific circumstances and the available *** of other rarer MODY subtypes is individu-alized,with decisions made on a case-by-case ***,a collaborative approach involving expert diabetes and obstetric teams is crucial for the compre-hensive management of MODY pregnancies.

关键词： Diabetes Pregnancy Maturity-onset diabetes of the young Insulin Sulphonylurea Glucokinase Hepatocyte nuclear factor 1-alpha,hepatocyte nuclear factor 1-beta,and hepatocyte nuclear factor 4-alpha

Sustainable plasticulture in Chinese agriculture: a review of challenges and routes to achieving long-term food and ecosecurity

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Frontiers of Agricultural Science and Engineering 2024年第1期11卷 155-168页

作者： Samuel j.CUSWOrTH William j.DAVIES Martin r.MCAINSH Carly j.STEVENS Weilu WANG Lancaster Environment Centre Lancaster UniversityLancasterLA14YQUK The Institutes of Agricultural Science and Technology Development Yangzhou UniversityYangzhou 225009China

Plastic pollution is global concern, affecting most aspects of global food production systems. Plasticulture, a practice used in agriculture to improve crop quality and quantity, among other factors, is a significant source of plastic pollution. This review examines the extent of plasticulture in China, the implications of the practice across decades of use and the legislative instruments used to resolve those issues. It briefly assesses the effectiveness of these policies and proposes possible future innovations to promote increases in long-term food and eco-security, where sustainable plasticulture is a key agent for change. While plasticulture has increased agricultural productivity in growth-limiting conditions, plastic pollution in agricultural soils has become acute in China. Consequently, plastic pollution is having deleterious effects on soil health and in turn, crop productivity in China. Plastic pollution in agriculture is a multifaceted issue and so proposed solutions should be informed by this complexity. Current measures do not reflect a holistic approach to solving this socioecological challenge and adopt a top-down approach, with little or no supportive mechanisms. Future recommendations need to consider the particular set of conditions that influence the production, use and end-of-life management of agriplastics,specific to the environmental, economic and social conditions in each location.

关键词： Circular plastics economy crop production food security plastic pollution sustainable plasticulture

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