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COPD急剧恶化的治疗

国外医学（呼吸系统分册） 1991年第2期11卷 78-81页

作者： rosen rt 董天光

慢性阻塞性肺疾病(COPD)的早期评价,应重点考虑可使心肺功能进一步恶化的诸因素,如气胸、肺栓塞、呼吸系感染、神经肌肉异常等.最近COPD 治疗大量依靠气溶胶型支气管扩张剂的局部吸入,如β肾上腺素药、抗胆碱药、皮质类固醇、茶碱,还有... 详细信息

慢性阻塞性肺疾病(COPD)的早期评价,应重点考虑可使心肺功能进一步恶化的诸因素,如气胸、肺栓塞、呼吸系感染、神经肌肉异常等.最近COPD 治疗大量依靠气溶胶型支气管扩张剂的局部吸入,如β肾上腺素药、抗胆碱药、皮质类固醇、茶碱,还有给氧等,能有效逆转COPD 的急剧恶化.

关键词： COPD 呼吸衰竭支气管扩张剂

Mathematical modelling of translational motion of rail-guided cart with suspended payload

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2007年第9期8卷 1395-1400页

作者： MITREV rosen Department of Engineering Logistics Material handling and Construction MachinesTechnical University of SofiaSofia 1000Bulgaria

In this paper modelling of the translational motion of transportation rail-guided cart with rope suspended payload is considered. The linearly moving cart,driven by a travel mechanism,is modelled as a discrete six degrees of freedom (DOF) dynamic system. The hoisting mechanism for lowering and lifting the payload is considered and is included in the dynamic model as one DOF system. Differential equations of motion of the cart elements are derived using Lagrangian dynamics and are solved for a set of real-life constant parameters of the cart. A two-sided interaction was observed between the swinging payload and the travel mechanism. Results for kinematical and force parameters of the system are obtained. A verification of the proposed model was conducted.

关键词： Transportation rail-guided cart Travel mechanism Swinging payload Discrete dynamical model Mathematical model

Poles of L-Functions on Quaternion Groups

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Chinese Annals of Mathematics,Series B 2014年第4期35卷 519-526页

作者： ?etin ürtS Department of Mathematics TOBB University of Economics and Technology Ankara Turkey

The author shows that the(partial) standard Langlands L-functions on quarternion groups have at most simple poles at certain positive integers.

关键词： Siegel Eisenstein series L-Functions Quaternion groups RegularizedSiegel-Weil formula

Finding stable multi-component materials by combining cluster expansion and crystal structure predictions

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npj Computational Materials 2023年第1期9卷 2137-2146页

作者： Adam Carlsson Johanna rosen Martin Dahlqvist Materials Design Department of PhysicsChemistryand Biology(IFM)Linköping UniversitySE-58183 LinköpingSweden

A desired prerequisite when performing a quantum mechanical calculation is to have an initial idea of the atomic positions within an approximate crystal *** atomic positions combined should result in a system located in,or close to,an energy ***,designing low-energy structures may be a challenging task when prior knowledge is scarce,specifically for large multi-component systems where the degrees of freedom are close to *** this paper,we propose a method for identification of low-energy crystal structures within multi-component systems by combining cluster expansion and crystal structure predictions with density-functional theory *** structure prediction searches are applied to the Mo_(2)AlB_(2) and Sc2AlB_(2) ternary systems to identify candidate structures,which are subsequently used to explore the quaternary(pseudo-binary)(Mo_(x)Sc_(1–x))2AlB_(2) system through the cluster expansion formalism utilizing the ground-state search ***,we show that utilizing low-energy structures found within the cluster expansion ground-state search as seed structures within crystal structure predictions of(Mo_(x)Sc_(1–x))2AlB_(2) can significantly reduce the computational *** this combined approach,we not only correctly identified the recently discovered Mo_(4/3)Sc_(2/3)AlB_(2) i-MAB phase,comprised of in-plane chemical ordering of Mo and Sc and with Al in a Kagomélattice,but also predict additional low-energy structures at various *** result demonstrates that combining crystal structure prediction with cluster expansion provides a path for identifying low-energy crystal structures in multi-component systems by employing the strengths from both frameworks.

关键词： structure cluster crystal

Fresnel incoherent correlation hologram-a review(Invited Paper)

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Chinese Optics Letters 2009年第12期7卷 1134-1141页

作者： Joseph rosen Barak Katz Gary Brooker Department of Electrical and Computer Engineering Ben-Gurion University of the NegevP.O. Box 653 Beer-Sheva 84105 Israel Johns Hopkins University Microscopy Center Montgomery County Campus Advanced Technology Laboratory Whiting School of Engineering 9605 Medical Center Drive Suite 240Rockville MD 20850 USA

Holographic imaging offers a reliable and fast method to capture the complete three-dimensional （3D） information of the scene from a single perspective. We review our recently proposed single-channel optical system for generating digital Fresnel holograms of 3D real-existing objects illuminated by incoherent light. In this motionless holographic technique, light is reflected, or emitted from a 3D object, propagates through a spatial light modulator （SLM）, and is recorded by a digital camera. The SLM is used as a beamsplitter of the single-channel incoherent interferometer, such that each spherical beam originated from each object point is split into two spherical beams with two different curve radii. Incoherent sum of the entire interferences between all the couples of spherical beams creates the Fresnel hologram of the observed 3D object. When this hologram is reconstructed in the computer, the 3D properties of the object are revealed.

关键词： Color holography Digital holographic imaging Holographic techniques Spatial light modulators Three dimensional imaging Zone plates

Transition metal carbides as cathode supports for PEM fuel cells

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Nano Research 2022年第12期15卷 10218-10233页

作者： Eliran R.Hamo Brian A.rosen Department of Materials Science and Engineering Tel Aviv UniversityRamat Aviv69987001Israel

As energy demands increase and environmental issues loom,fuel cells(FCs)have attracted significant attention as an alternative to conventional energy *** use encompasses portable applications,transportation,and a stationary grid-power mainly due to their low-temperature operation and quick ***,the primary challenge is improving fuel cell durability to meet 2025 *** of Energy targets(e.g.,8,000+h for automotive drive cycle).Proton exchange membrane fuel cell(PEMFC)catalysts currently suffer from low durability,undermining their wide-scale deployment into the consumer and industrial *** group metals(PGMs)are still the most common catalysts used in PEMFCs as they provide among the highest activity for electrode reactions and lifetime *** effective way to decrease Pt loading is the adoption of supports to enhance both Pt dispersion and its *** of the carbon-based support was identified to be the major contributor to performance degradation as they suffer from parasitic oxidation to CO_(2)(at the cathode).Therefore,there is a significant interest in exploring stable alternatives to replace carbon supports in *** metal carbides(TMCs)have attracted significant attention over the last several years as a possible candidate to replace carbon-based catalyst supports in fuel *** these advantages over carbon supports,the large-scale deployment of TMC-based supports in fuel cells is still hindered by concerns of durability at the high potential on the cathode during start-up and shutdown ***,we address the most relevant studies concerning TMCs as supports for acidic oxygen reduction reaction(ORR)catalysis,including viewpoints about the surface and bulk design of the support,as well as the design of the catalyst itself to enhance the interaction and dispersion with the support.

关键词： carbides fuel cells catalysis durability corrosion

The role of undifferentiated adipose-derived stem cells in peripheral nerve repair

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Neural Regeneration Research 2018年第5期13卷 757-763页

作者： Rui Zhang Joseph M.rosen Dartmouth Geisel School of Medicine Dartmouth-Hitchcock Medical Center

Peripheral nerve injuries impose significant health and economic consequences, yet no surgical repair can deliver a complete recovery of sensory or motor function. Traditional methods of repair are less than ideal： direct coaptation can only be performed when tension-free repair is possible, and transplantation of nerve autograft can cause donor-site morbidity and neuroma formation. Cell-based therapy delivered via nerve conduits has thus been explored as an alternative method of nerve repair in recent years. Stem cells are promising sources of the regenerative core material in a nerve conduit because stem cells are multipotent in function, abundant in supply, and more accessible than the myelinating Schwann cells. Among different types of stem cells, undifferentiated adipose-derived stem cell（uASC）, which can be processed from adipose tissue in less than two hours, is a promising yet underexplored cell type. Studies of uASC have emerged in the past decade and have shown that autologous uASCs are non-immunogenic, easy to access, abundant in supply, and efficacious at promoting nerve regeneration. Two theories have been proposed as the primary regenerative mechanisms of uASC： in situ trans-differentiation towards Schwann cells, and secretion of trophic and anti-inflammatory factors. Future studies need to fully elucidate the mechanisms, side effects, and efficacy of uASC-based nerve regeneration so that uASCs can be utilized in clinical settings.

关键词： peripheral nerve injury adipose-derived stem cells Schwann cells cell therapy nerve conduits axonal regeneration stem cell differentiation neurotrophic factors anti-apoptosis immunosuppression

Quantitative measures for assessment of the hydraulic excavator digging efficiency

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2012年第12期13卷 926-942页

作者： Dragoslav JANOSEVIC rosen MITREV Boban ANDJELKOVIC Plamen PETROV Faculty of Mechanical Engineering University of Nis Faculty of Mechanical Engineering Technical University of Sofia

In this paper,quantitative measures for the assessment of the hydraulic excavator digging efficiency are proposed and *** following factors are considered:(a) boundary digging forces allowed for by the stability of an excavator,(b) boundary digging forces enabled by the driving mechanisms of the excavator,(c) factors taking into consideration the digging position in the working range of an excavator,and(d) sign and direction of potential digging resistive force.A corrected digging force is defined and a mathematical model of kinematic chain and drive mechanisms of a five-member excavator configuration was developed comprising:an undercarriage,a rotational platform and an attachment with boom,stick,and *** the basis of the mathematical model of the excavator,software was developed for computation and detailed analysis of the digging forces in the entire workspace of the *** using the developed software,the analysis of boundary digging forces is conducted and the corrected digging force is determined for two models of hydraulic excavators of the same mass(around 17 000 kg) with identical kinematic chain parameters but with different parameters of manipulator driving *** results of the analysis show that the proposed set of quantitative measures can be used for assessment of the digging efficiency of existing excavator models and to serve as an optimization criterion in the synthesis of manipulator driving mechanisms of new excavator models.

关键词： Hydraulic excavators Digging efficiency Quantitative measures

One-Pot Synthesis of N-Boc-2, 5-bis(trimethylsilyl)pyrrolidine

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Chinese Chemical Letters 2001年第12期12卷 1061-1064页

作者： Dong, JC Li, rt Cheng, TM Peking Univ Sch Pharmaceut Sci Dept Bioorgan Chem Beijing 100083 Peoples R China

N-Boc-2, 5-bis(trimethylsilyl)pyrrolidine 4 was synthesized from the reaction of N-Boc-pyrrolidine 1 with trimethylsilyl chloride (TMSCl) at optional temperature in one-pot in good yield.

关键词： N-Boc-2 5-bis(trimethylsilyl)pyrrolidine trimethylsilylation one-pot