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Asian Journal of Andrology 2013年第6期15卷 795-798,I0009页

作者： J Ullrich Schwarzer Heiko Steinfatt Heiko Steinfatt Manfred Schleyer Frank M Kōhn Klaus Fiedler2, Irene von Hertwig Gottfried Krüsmann wolfgang würfel Andrologie Centrum MOnchen MOnchen D-81241 Germany Kinderwunsch Centrum MOnchen MOnchen D-81241 Germany Andrologicum MOnchen MOnchen D-80331 Germany

In 220 consecutive patients with non-obstructive azoospermia, sperm retrieval was attempted by a combination of conventional and microdissection testicular sperm extraction （TESE）. For sperm retrieval, 2-3 conventional biopsies were performed followed by a microdissection TESE in cases of negative conventional biopsies. During the surgery, the vasculature of the testis was assessed using the operative microscope, and the location of positive biopsies was registered in relation to the blood supply. The overall sperm retrieval rate was 58.2%. From the initial conventional biopsies, sperm could be retrieved in 46.8% of the patients. with microdissection TESE, sperm could be retrieved from an additional 11.4% of the patients. The further use of microdissection TESE improved the sperm retrieval rate significantly （P=0.017）. No significant accumulation of positive biopsies was found towards the rete testis or the main testicular vessels.

关键词： intracytoplasmic sperm injection male infertility microdissection testicular sperm extraction non-obstructiveazoospermia sperm retrieval

Skeletal microstructures of cheilostome bryozoans(phylum Bryozoa,class Gymnolaemata):crystallography and secretion patterns

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Marine Life Science & Technology 2024年第3期6卷 405-424页

作者： Christian Grenier Erika Griesshaber wolfgang Schmahl Björn Berning Antonio G.Checa Departamento de Estratigrafía y Paleontología Universidad de Granada18071 GranadaSpain Instituto Andaluz de Ciencias de La Tierra CSIC-Universidad de Granada18100 ArmillaSpain Department of Earth and Environmental Sciences Ludwig-Maximilians Universität80333 MunichGermany Institute for Geology University of Hamburg20146 HamburgGermany

Gymnolaemata bryozoans produce CaCO3 skeletons of either calcite,aragonite,or *** extensive research,their crystallography and biomineralization patterns remain *** present a detailed study of the microstructures,min-eralogy,and crystallography of eight extant cheilostome species using scanning electron microscopy,electron backscatter diffraction,atomic force microscopy,and micro-computed *** distinguished five basic microstructures,three calcitic(tabular,irregularly platy,and granular),and two aragonitic(granular-platy and fibrous).The calcitic microstruc-tures consist of crystal aggregates that transition from tabular or irregularly platy to granular *** aragonite consists of fibers arranged into *** all cases,the crystallographic textures are axial,and stronger in aragonite than in calcite,with the c-axis as the fiber *** reconstruct the biomineralization sequence in the different species by considering the distribution and morphology of the growth fronts of crystals and the location of the secretory *** bimineralic species,calcite formation always predates aragonite *** interior compound walls,growth proceeds from the cuticle toward the zooecium *** conclude that,with the exception of tabular calcite,biomineralization is remote and occurs within a relatively wide extrapallial space,which is consistent with the inorganic-like appearance of the *** biomineralization mode is rare among invertebrates.

关键词： Biomineralization Bryozoan Skeleton Calcite Aragonite Electron backscatter diffraction

Limits on light emission from silicon

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Chinese Optics Letters 2009年第4期7卷 268-270页

作者： Peter würfel Institut für Angewandte Physik Universitt KarlsruheD-76128 KarlsruheGermany

Although silicon is an indirect semiconductor, light emission from silicon is governed by the same gener- alized Planck＇s radiation law as the emission from direct semiconductors. The emission intensity is given by the absorptance of the volume in which there is a difference of the quasi Fermi energies. A difference of the Fermi energies may result h＇om the absorption of external light （photoluminescence） or from the injection of electrons and holes via selective contacts （electroluminescence）. The quantum efficiency may be larger than 0.5 for carrier densities below 10^15 cm^-3. At larger densities, non-radiative recombination, in particular Auger recombination dominates. At all carrier densities, the relation between emission intensity and difference of the quasi Fermi energies is maintained. Since this difference is equal to the voltage of a properly designed solar cell, luminescence is the key indicator of material quality for solar cells.

关键词： Carrier concentration Fermi level Light Light emission Photoluminescence Semiconducting silicon Silicon

EVA NEXUS-Phaco performance study

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International Journal of Ophthalmology(English edition) 2024年第8期17卷 1447-1452页

作者： Lukas Feldhaus Andreas Ohlmann Stefan Kassumeh Siegfried Priglinger wolfgang Mayer Department of Ophthalmology University HospitalLudwig-Maximilians-University MunichMunich 80336Germany

AIM:To investigate a novel phacoemulsification system“EVA NEXUS”(D.O.R.C.,Dutch Opthalmic Research Center)in comparison to the existing system“EVA”in clinical *** to compare both phacoemulsification systems in terms of efficiency,safety and postoperative inflammatory ***:In this study standardized cataract surgery was performed on both eyes of the study participant,using the“EVA system”(control group,n=20)on one eye and the“EVA NEXUS system”(intervention group,n=20)on the other *** patients with cataract LOCS Grading 1-3 and no accompanying eye diseases were included in this study.A total of 20 patients were included in this study,with each treatment arm including 20 *** surgery a 0.1 mL aqueous humor sample was collected 1min after phacoemulsification to measure the total prostaglanin E2 concentrations using an enzyme-linked immunosorbent *** endothelial cell count,visual and refractive outcomes,and anterior chamber flare were evaluated preoperatively,and 1d,1wk,and 3mo ***:There were no statistically significant differences between both groups regarding intraoperative safety parameters including effective phacoemulsification time(P=0.904),balanced saline solution flow(P=0.701)and total surgery time(P=0.565).Postoperative prostaglandin E2 levels,anterior chamber flare as well as endothelial cell loss tended to be lower in the NEXUS-Group,however not being statistically significant(P=0.718;0.164;0.486).Both systems provided similar clinical outcomes,regarding best corrected visual acuity and refractive parameters,showing no statistically significant differences between both ***:Both systems show a high level of safety and efficency with similar results in terms of safety parameters including postoperative inflammatory activity and endothelial cell loss as well as visual and refractive *** statistically not significant,the EVA NEXUS system tends to cause less postoperative inflammatio

关键词： cataract surgery phacoemulsification fluidics instrument

Going deep:Roots,carbon,and analyzing subsoil carbon dynamics

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Molecular Plant 2024年第1期17卷 1-3页

作者： Ezhilmathi Angela Joseph Fernando Michael Selvaraj Yusaku Uga wolfgang Busch Hunt Bowers Joe Tohme Alliance of Bioversity International and CIAT Km 17 Recta Cali-PalmiraAprtado Aereo 6713Cali 763537Colombia National Institute of Agrobiological Sciences(NIAS) TsukubaIbaraki 305-0856Japan Salk Institute for Biological Studies 10010 N Torrey Pines RoadLa JollaCA 92037USA Earth Optics Suite 840ArlingtonVA 22202USA

Agricultural practices currently contribute to the emission of approximately 10%–12%atmospheric greenhouse gasses,with tillage agriculture accelerating soil disruption and carbon dioxide ***,various options exist,such as converting new lands for agriculture,promoting healthier plant-based diets,adopting advanced management technologies,and minimizing food ***,these measures alone are insufficient to ensure environmental sustainability within planetary boundaries.

关键词： soil measures carbon

Hierarchical CoFe@N-Doped Carbon Decorated wood Carbon as Bifunctional Cathode in wearable Zn-Air Battery

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Energy & Environmental Materials 2024年第1期7卷 42-50页

作者： Kelong Ao Xiangyang Zhang Renat R.Nazmutdinov Di wang Jihong Shi Xian Yue Jianguo Sun wolfgang Schmickler walid A.Daoud Department of Mechanical Engineering City University of Hong KongHong Kong 999077China Kazan National Research Technological University 420015 KazanRussian Federation School of Textile and Garment Anhui Polytechnic UniversityWuhu 241000China wood Materials Science Institute for Building MaterialsETH Zürich8093 ZürichSwitzerland Am Sandhaken 18 D-89069 UlmGermany

Rechargeable Zn-air batteries(ZAB)have drawn extensive attention due to their eco-friendliness and ***,the lack of high-performance and low-cost oxygen redox reactions(OER and ORR)catalysts has become one of the main stumbling blocks in their ***,we successfully fabricate a CoFe nanobubble encapsulated in nitrogen-doped carbon nanocage on wood carbon support(CoFe@NC/wC)via pyrolysis of a novel Prussian blue analog(PBA)/spruce *** hierarchical CoFe@NC/wC catalyst exhibits an excellent potential difference of 0.74 V between the OER potential at 10 mA cm^(-2)and half-wave potential of ORR in 0.1 M KOH,comparable to recently reported preeminent ***,CoFe@NC/wC shows outstanding electrochemical performance in liquid ZAB,with a peak power density of 138.9 mw cm^(-2)and a specific capacity of 763.5 mAh g^(-1).More importantly,a bacterial cellulose nanofiber reinforced polyacrylic acid(BC-PAA)hydrogel electrolyte shows ultrahigh tensile-breaking stress of 1.58 *** conjunction with the as-prepared CoFe@NC/wC catalyst,BC-PAA-based wearable ZAB displays impressive rechargeability and foldability,and can power portable electronics,such as electronic timer and mobile phone,in bent *** work provides a new approach toward high-activity and low-cost catalysts for ZAB.

关键词： biomass-based catalyst DFT computation hydrogel electrolyte oxygen redox reactions wearable Zn-air battery

Superexchange and charge transfer in the nickelate superconductor La_(3)Ni_(2)O_(7) under pressure

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Science China(Physics,Mechanics & Astronomy) 2024年第11期67卷 1-8页

作者： wéi wú Zhihui Luo Dao-Xin Yao Meng wang Center for Neutron Science and Technology Guangdong Provincial Key Laboratory of Magnetoelectric Physics and DevicesSchool of PhysicsSun Yat-sen UniversityGuangzhou 510275China

Recently, a bulk nickelate superconductor La_(3)Ni_(2)O_(7) is discovered at pressures with a remarkable high transition temperature T_(c)~ 80 K. Here, we study a Hubbard model with tight-binding parameters derived from ab initio calculations of La_(3)Ni_(2)O_(7),by employing large scale determinant quantum Monte Carlo and cellular dynamical mean-field theory. Our result suggests that the superexchange couplings in this system are comparable to that of cuprates. The system is a charge transfer insulator as the hole concentration becomes four per site at large Hubbard U. Upon hole doping, two low-energy spin-singlet bands emerge in the system exhibiting distinct correlation properties: while the one composed of the out-of-plane Ni-d_(3z^(2)-r^(2)) and O-p_(z) orbitals demonstrates strong antiferromagnetic correlations and narrow effective bandwidth, the in-plane singlet band consisting of the Ni-d_(x^(2)-y^(2)) and O-p_(x)/p_(y) orbitals is in general more itinerant. Over a broad range of hole doping, the doped holes occupy primarily the d_(x^(2)-y^(2)) and p_(x)/p_(y) orbitals, whereas the d_(3z^(2)-r^(2)) and p_(z) orbitals retain underdoped. we propose an effective t-J model to capture the relevant physics and discuss the implications of our result for comprehending the La_(3)Ni_(2)O_(7) superconductivity.

关键词： superconductivity nickelate superconductors Hubbard model superexchange charge transfer insulator quantum Monte Carlo

Towards engineering a portable platform for laparoscopic pre-training in virtual reality with haptic feedback

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虚拟现实与智能硬件（中英文） 2024年第2期6卷 83-99页

作者： Hans-Georg ENKLER wolfgang KUNERT Stefan PFEFFER Kai-Jonas BOCK Steffen AXT Jonas JOHANNINK Christoph REICH Furtwangen University 78120 FurtwangenGermany University Hospital and Faculty of Medicine Tuebingen 72076 TuebingenGermany

Background Laparoscopic surgery is a surgical technique in which special instruments are inserted through small incision holes inside the *** some time,efforts have been made to improve surgical pre training through practical exercises on abstracted and reduced *** The authors strive for a portable,easy to use and cost-effective Virtual Reality-based(VR)laparoscopic pre-training platform and therefore address the question of how such a system has to be designed to achieve the quality of today's gold standard using real tissue *** VR controllers are limited regarding haptic *** haptic feedback is necessary or at least beneficial for laparoscopic surgery training,the platform to be developed consists of a newly designed prototype laparoscopic VR controller with haptic feedback,a commercially available head-mounted display,a VR environment for simulating a laparoscopic surgery,and a training *** To take full advantage of benefits such as repeatability and cost-effectiveness of VR-based training,the system shall not require a tissue sample for haptic *** is currently calculated and visually displayed to the user in the VR *** the prototype controller,a first axis was provided with perceptible feedback for test *** of the prototype VR controllers can be combined to simulate a typical both-handed use case,e.g.,laparoscopic suturing.A Unity based VR prototype allows the execution of simple standard *** The first prototype enables full operation of a virtual laparoscopic instrument in *** addition,the simulation can compute simple interaction *** challenges lie in a realistic real-time tissue simulation and calculation of forces for the haptic *** weaknesses were identified in the first hardware prototype,which will be improved in subsequent *** degrees of freedom of the controller are to be provided with haptic *** make forces t

关键词： Laparoscopic surgery Training Virtual reality Controller Haptic feedback Kinesthetic skills

Superplasticity of fine-grained Mg-10Li alloy prepared by severe plastic deformation and understanding its deformation mechanisms

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Journal of Magnesium and Alloys 2024年第1期12卷 316-331页

作者： H.T.Jeong S.w.Lee w.J.Kim Department of Materials Science and Engineering Hongik UniversityMapo-guSangsu-dong 72-1Seoul 121-791Republic of Korea

The superplastic behavior and associated deformation mechanisms of a fine-grained Mg-10.1 Li-0.8Al-0.6Zn alloy(LAZ1011)with a grain size of 3.2μm,primarily composed of the BCCβphase and a small amount of the HCPαphase,were examined in a temperature range of 473 K to 623 *** microstructural refinement of this alloy was achieved by employing high-ratio differential speed *** best superplasticity was achieved at 523 K and at strain rates of 10^(-4)-5×10^(-4)s^(-1),where tensile elongations of 550±600%were *** the heating and holding stage of the tensile samples prior to tensile loading,a significant increase in grain size was observed at temperatures above 573 ***,it was important to consider this effect when analyzing and understanding the superplastic deformation behavior and *** the investigated strain rate range,the superplastic flow at low strain rates was governed by lattice diffusion-controlled grain boundary sliding,while at high strain rates,lattice diffusion-controlled dislocation climb creep was the rate-controlling deformation *** was concluded that solute drag creep is unlikely to *** the late stages of deformation at 523 K,it was observed that grain boundary sliding led to the agglomeration of theαphase,resulting in significant strain *** mechanism maps were constructed forβ-Mg-Li alloys in the form of 2D and 3D formats as a function of strain rate,stress,temperature,and grain size,using the constitutive equations for various deformation mechanisms derived based on the data of the current tests.

关键词： Magnesium-lithium alloy Superplasticity Severe plastic deformation Grain size Grain growth

Pervasive Attentive Neural Network for Intelligent Image Classification Based on N-CDE’s

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Computers, Materials & Continua 2024年第4期79卷 1137-1156页

作者： Anas w.Abulfaraj Department of Information Systems Faculty of Computing and Information TechnologyKing Abdulaziz UniversityRabigh21911Saudi Arabia

The utilization of visual attention enhances the performance of image classification *** attentionbased models have demonstrated notable performance,but many of these models exhibit reduced accuracy when confronted with inter-class and intra-class similarities and ***-Controlled Differential Equations(N-CDE’s)and Neural Ordinary Differential Equations(NODE’s)are extensively utilized within this ***’s possesses the capacity to effectively illustrate both inter-class and intra-class similarities and differences with enhanced *** this end,an attentive neural network has been proposed to generate attention maps,which uses two different types of N-CDE’s,one for adopting hidden layers and the other to generate attention *** distinct attention techniques are implemented including time-wise attention,also referred to as bottom N-CDE’s;and element-wise attention,called topN-CDE’***,a trainingmethodology is proposed to guarantee that the training problem is sufficiently *** classification tasks including fine-grained visual classification andmulti-label classification,are utilized to evaluate the *** proposedmethodology is employed on five publicly available datasets,including CUB-200-2011,ImageNet-1K,PASCAL VOC 2007,PASCAL VOC 2012,and MS *** obtained visualizations have demonstrated that N-CDE’s are better appropriate for attention-based activities in comparison to conventional NODE’s.

关键词： Differential equations neural-controlled DE image classification attention maps N-CDE’s