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Vector harmonic mode-locking by acoustic resonance

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Photonics Research 2021年第8期9卷 1432-1438页

作者： SERGEY SERGEYEV stanislav KOLPAKOV YURY LOIKA Aston Institute of Photonic Technologies Aston UniversityBirminghamB47ETUK

For an Er-doped fiber laser,for the first time,to the best of our knowledge,we demonstrate both experimentally and theoretically a novel mechanism of harmonic mode-locking based on the electrostriction effect leading to excitation of the torsional acoustic modes in the transverse section of the *** exited torsional acoustic modes modulate the fiber birefringence that results in synchronization of oscillations at the harmonic modes and the linewidth narrowing with the increased signal-to-noise ratio of 30 d *** adjusting the in-cavity birefringence based on tuning the polarization controller,we enable the selection of the harmonic mode to be stabilized.

关键词： fiber polarization tuning

Retinal ganglion cell neuroprotection by growth factors and exosomes:lessons from mesenchymal stem cells

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Neural Regeneration Research 2018年第2期13卷 228-229页

作者： Ben Mead stanislav Tomarev Section of retinal ganglion cell biology laboratory of retinal cell and molecular biologynational eye institutenational institutes of healthBethesdaMDUSA

Retinal ganglions cells （RGCs） are responsible for propagating electrochemical information from the eye to the brain along their axons which make up the optic nerve. The loss of RGCs is characteristic in several conditions such as glaucoma and trau- matic optic neuropathy and leads to visual loss and blindness. While no therapy exists to directly treat RGCs, the use of bone marrow-derived mesenchymal stem cells （BMSCs） has shown promise in eliciting significant RGC neuroprotection.

关键词： BMSCs Retinal ganglion cell neuroprotection by growth factors and exosomes lessons from mesenchymal stem cells PDGFR

Regulation of Sulfate Uptake and Assimilation——the Same or Not the Same？

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Molecular Plant 2010年第2期3卷 314-325页

作者： Jean-Claude Davidian stanislav Kopriva Unite mixte de recherche Biochimie et Physiologie Molculaire des Plantes Montpellier SupAgro/CNRS/INRA/UM2 2 place Pierre Viala 34060 MontpellierCedex 2 France Department of Metabolic Biology John Innes Centre Norwich NR4 7UH UK

Plant take up the essential nutrient sulfur as sulfate from the soil, reduce it, and assimilate into bioorganic compounds, with cysteine being the first product. Both sulfate uptake and assimilation are highly regulated by the demand for the reduced sulfur, by availability of nutrients, and by environmental conditions. In the last decade, great prog- ress has been achieved in dissecting the regulation of sulfur metabolism. Sulfate uptake and reduction of activated sulfate, adenosine 5＇-phosphosulfate （APS）, to sulfite by APS reductase appear to be the key regulatory steps. Here, we review the current knowledge on regulation of these processes, with special attention given to similarities and differences.

关键词： Metabolic regulation nutrient and metal transport nutrition primary metabolism sulfate uptake sulfur metabolism.

Contact mechanics of pad of grasshopper (Insecta:ORTHOPTERA) by finite element methods

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Chinese Science Bulletin 2009年第4期54卷 549-555页

作者： DAI ZhenDong GORB stanislav Institute of Bio-inspired Structure and Surface Engineering Nanjing University of Aeronautics and Astronautics Nanjing Jiangsu China 210016 Evolutionary Biomaterials Group Max-Planck-lnstitute for Metals Research Germany 70569

During locomotion, insect feet endure dramatic impact force and generate adhesive force which is controlled by the architecture of the foot. The patterns of smooth attachment pads in insect feet vary widely among insect orders and families. The functional significance of the micro-structure and geometric design of insect feet remains largely unknown. In this study, we developed a two-dimensional finite element model of a grasshopper's attachment pad. Realistic geometric microstructure and material properties are applied in the biomechanical analysis of the structural behavior during contact. Here we use scanning electronic microscopy to study the microstructure of the grasshopper's pad, and then use the finite element method to calculate the deformation vector fields, contact stiffness, contact area, function of the airbag and strain fields during the contact process. The results reveal that the geometric design and material topology of a grasshopper's pads are very effective in reducing contact stiffness, increasing contact area and generating high friction force during the contact procedure. The rod-containing structure supporting the soft exocuticle makes the pads highly adaptive to various surfaces and decreases the stress inside the pads.

关键词：蚱蜢接触机理昆虫脚接触表面生物模拟有限元分析

Viscosity of slags from the joint smelting of oxidized nickel and sulfide copper ores

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Transactions of Nonferrous Metals Society of China 2023年

作者： Alexander KLYUSHNIKOV Svetlana SERGEEVA Roza GULYAEVA Alexander VUSIKHIS Lyudmila UDOEVA stanislav TYUSHNYAKOV Laboratory of Non-Ferrous Metals Pyrometallurgy， Department of Non-Ferrous Metals， Institute of Metallurgy of the Ural Branch of the Russian Academy of Sciences 2. Laboratory of Rare Refractory Metals， Department of Non-Ferrous Metals， Institute of Metallurgy of the Ural Branch of the Russian Academy of Sciences

The work is devoted to the viscosity determination of molten slags from the joint smelting of oxidized nickel and sulfide copper ores. The model slags were synthesized close in composition and structure to real samples， and limiting the investigated composition range: iron-containing slag (8.9 wt.% CaO， 11.8 MgO， 12.5 Al2O3， 47.4 SiO2， 13.3 FeO， 5.0 Fe2O3) and iron-free slag formed by removing iron oxides from the iron-containing slag (12.5 wt.% CaO， 16.0 MgO， 9.4 Al2O3， 58.3 SiO2). The experimental (vibrational method) viscosity values for iron-containing (1550–1300 ℃) and iron-free (1550–1400 ℃) model slags were 3.1–23.3 and 12.8–45.5 dPa·s， respectively. Viscosity estimation by the Kalmanovitch–Frank model showed a discrepancy with the experimental data for iron-containing slag. Regression analysis (by Weimann–Frenkel–Urbain formalism) of the experimental data was carried out， and original empirical models were proposed to predict the primary model slags viscosity in the considered temperature range. Reducing the basicity from 0.7 (iron-containing slag) to 0.6 (iron-free slag) increased viscous flow activation energy from 204 to 236 kJ·mol–1. To maintain optimal slag viscosity， joint smelting of oxidized nickel and sulfide copper ores should be carried out at a temperature not lower than 1400 ℃.

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氧化镍和硫化铜矿联合熔炼炉渣的黏度

Transactions of Nonferrous Metals Society of China 2023年第10期33卷 3168-3184页

作者： Alexander KLYUSHNIKOV Svetlana SERGEEVA Roza GULYAEVA Alexander VUSIKHIS Lyudmila UDOEVA stanislav TYUSHNYAKOV Laboratory of Non-Ferrous Metals Pyrometallurgy Department of Non-Ferrous MetalsInstitute of Metallurgy of the Ural Branch of the Russian Academy of Sciences101Amundsen StreetYekaterinburg 620016Russia Laboratory of Rare Refractory Metals Department of Non-Ferrous MetalsInstitute of Metallurgy of the Ural Branch of the Russian Academy of Sciences101Amundsen StreetYekaterinburg 620016Russia

测定氧化镍和硫化铜矿联合冶炼熔渣的黏度。制备的模拟熔渣与实际熔渣的成分和结构相似,并限制研究的熔渣的成分范围,含铁熔渣的成分(质量分数)为:8.9%CaO、11.8%MgO、12.5%Al_(2)O_(3)、47.4%SiO_(2)、13.3%FeO和5.0%Fe_(2)O_(3);无铁... 详细信息

测定氧化镍和硫化铜矿联合冶炼熔渣的黏度。制备的模拟熔渣与实际熔渣的成分和结构相似,并限制研究的熔渣的成分范围,含铁熔渣的成分(质量分数)为:8.9%CaO、11.8%MgO、12.5%Al_(2)O_(3)、47.4%SiO_(2)、13.3%FeO和5.0%Fe_(2)O_(3);无铁熔渣是将含铁熔渣中的氧化铁去除得到,其成分(质量分数)为:12.5%CaO、16.0%MgO、9.4%Al_(2)O_(3)和58.3%SiO_(2)。由振动法测试的含铁熔渣(1550~1300℃)和无铁熔渣(1550~1400℃)的黏度实验值分别为0.31~2.33 Pa·s和1.28~4.55 Pa·s。由Kalmanovitch-Frank模型预测的含铁熔渣的黏度值与实验值存在偏差。通过Weimann-Frenkel-Urbain方程对实验数据进行回归分析,提出可预测所考虑温度范围内的初级熔渣黏度的原始经验模型。当碱度从0.7(含铁熔渣)降低到0.6(无铁熔渣),黏性流动活化能从204 kJ/mol增加到236kJ/mol。为了保持最佳熔渣黏度,氧化镍和硫化铜矿联合冶炼的温度应不低于1400℃。

关键词：熔渣黏度振动式黏度计 Kalmanovitch–Frank模型 Weimann–Frenkel–Urbain方程氧化镍矿硫化铜矿造锍熔炼

Comparative study in vivo of the osseointegration of 3D-printed and plasma-coated titanium implants

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世界骨科杂志:英文版 2023年第9期14卷 682-689页

作者： stanislav Bondarenko Volodymyr Filipenko Nataliya Ashukina Valentyna Maltseva Gennadiy Ivanov Iurii Lazarenko Dmytro Sereda Ran Schwarzkopf Department of Joint Pathology Sytenko Institute of Spine and Joint Pathology National Academy of Medical Sciences of UkraineKharkiv 61024Ukraine Laboratory of Connective Tissue Morphology Sytenko Institute of Spine and Joint Pathology National Academy of Medical Sciences of UkraineKharkiv 61024Ukraine Experimental Pathology Sytenko Institute of Spine and Joint Pathology National Academy of Medical Sciences of UkraineKharkiv 61024Ukraine Department of Traumatology Military medical clinical center of the Central regionVinnytsia 21018Ukraine Department of Surgery Odesa city hospital 11Odesa 65006Ukraine Hospital for Joint Diseases NYU Langone Orthopedic HospitalNY 10003United States

BACKGROUND Total hip arthroplasty is a common surgical treatment for elderly patients with osteoporosis,particularly in postmenopausal *** such cases,highly porous acetabular components are a favorable option in achieving ***,further discussion is needed if use of such acetabular components is justified under the condition of normal bone *** To determine the features of osseointegration of two different types of titanium implants[3-dimensional(3D)-printed and plasma-coated titanium implants]in bone tissue of a distal metaphysis in a rat femur *** This study was performed on 20 white male laboratory rats weighing 300-350 g aged 6 *** were divided into two groups of 10 animals,which had two different types of implants were inserted into a hole defect(2×3 mm)in the distal metaphysis of the femur:GroupⅠ:3D-printed titanium implant(highly porous);GroupⅡ:Plasma-coated titanium *** 45 and 90 d following surgery,the rats were sacrificed,and their implanted femurs were extracted for histological *** relative perimeter(%)of bone trabeculae[bone-implant contact(BIC%)]and bone marrow surrounding the titanium implants was *** Trabecular bone tissue was formed on the 45th day after implantation around the implants regardless of their type.45 d after surgery,group I(3D-printed titanium implant)and groupⅡ(plasma-coated titanium implant)did not differ in BIC%(83.51±8.5 vs 84.12±1.73;P=0.838).After 90 d,the BIC%was higher in group I(87.04±6.99 vs 81.24±7.62;P=0.049),compared to groupⅡ.The relative perimeter of the bone marrow after 45 d did not differ between groups and was 16.49%±8.58%for groupⅠ,and 15.88%±1.73%for groupⅡ.Futhermore,after 90 d,in groupⅠthe relative perimeter of bone marrow was 1.4 times smaller(12.96±6.99 vs 18.76±7.62;P=0.049)compared to the relative perimeter of bone marrow in groupⅡ.CONCLUSION The use of a highly porous titanium implant,manufactured with 3D printing,for acetabular com

关键词： Rats Hip arthroplasty Femur Porosity 3-dimensional printing Microscopy

Peutz-Jeghers syndrome:Diagnostic and therapeutic approach

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World Journal of Gastroenterology 2009年第43期15卷 5397-5408页

作者： Marcela Kopacova Ilja Tacheci stanislav Rejchrt Jan Bures 2nd Department of Medicine Charles University in PrahaFaculty of Medicine at Hradec KrálovéUniversity Teaching HospitalSokolská581Hradec Králové500 05 Czech Republic

Peutz-Jeghers syndrome(PJS)is an inherited,autosomal dominant disorder distinguished by hamartomatous polyps in the gastrointestinal tract and pigmented mucocutaneous *** of PJS is estimated from 1 in 8300 to 1 in 280 000 *** predisposes sufferers to various malignancies(gastrointestinal,pancreatic,lung,breast,uterine,ovarian and testicular tumors).Bleeding,obstruction and intussusception are common complications in patients with *** balloon enteroscopy(DBE)allows examination and treatment of the small *** using DBE may obviate the need for repeated urgent operations and small bowel resection that leads to short bowel *** and polypectomy of the entire small bowel is the gold standard in PJS *** enteroscopy(IOE)was the only possibility for endoscopic treatment of patients with PJS before the DBE *** DBE and IOE facilitate exploration and treatment of the small intestine. DBE is less invasive and more convenient for the pa- *** procedures are generally safe and useful. An overall recommendation for PJS patients includes not only gastrointestinal multiple polyp resolution,but also regular lifelong cancer screening(colonoscopy, upper endoscopy,computed tomography,magnetic resonance imaging or ultrasound of the pancreas, chest X-ray,mammography and pelvic examinationwith ultrasound in women,and testicular examination in men).Although the incidence of PJS is low,it is important for clinicians to recognize these disorders to prevent morbidity and mortality in these patients,and to perform presymptomatic testing in the first-degree relatives of PJS patients.

关键词：综合征治疗诊断黑斑肉

On the laboratory rearing of green dock leaf beetles Gastrophysa viridula （Coleoptera： Chrysomelidae）

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Insect Science 2011年第3期18卷 379-384页

作者： Dagmar Voigt Naoe Hosoda Jan Schuppert stanislav Gorb Evolutionary Biomaterials Group Department of Thin-Films and Biological Systems Max Planck Institute for Metals Research Stuttgart Department of Functional Morphology and Biomechanics Zoological Institute Christian Albrechts University of Kiel Kiel Germany Advanced Nano Materials Laboratory Interconnect Design Group National Institute for Materials Tsukuba Ibaraki Japan

Leaf beetles Gastrophysa viridula have attracted recently increased research interest from various points of view, since they are：（i） pest insects in rhubarb crops; （ii） potential biocontrol agents of dock plants Rumex spp. in grasslands; and （iii） a model species in ecological studies on insect population dynamics, biochemistry, behavior, biomechanics and biomimetics. The continuous rearing of beetles at standardized conditions may help to unify the fitness state of different individuals, allowing a better comparison of experimental results. The present communication suggests a modular space- and time-saving rearing method ofG. viridula in stackable faunariums under laboratory conditions, which has been successfully established and continuously used over the last 5 years. Several developmental stages were kept in separate boxes, and multiple generations were kept simultaneously, depending on the required number of beetles.

关键词： Chrysomelidae standardisation Rumex obtusifolius