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Morphological Variability in Vipera palaestinae along an Environmental Gradient

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Asian Herpetological Research 2012年第3期3卷 227-239页

作者： stanislav VOLYNCHIK National Collections of Natural History Department of ZoologyFaculty of Life SciencesTel Aviv University Ramat Aviv 69978Israel

The effect of local habitat conditions on organisms, including environmentally-induced morphological changes, constitutes an important aspect of macroecology and evolution. The degree of geographic intraspecific variation in body dimensions, corporeal ratios and scalation pattern among male and female Palestine vipers(Vipera palaestinae) in Israel were examined. Univariate and multivariate analyses using 20 variable features relating to metric and meristic characters were applied in order to determine the existence of geographic variability in this species. Univariate analysis revealed that the majority of morphological characters possess relatively minor interregional distinctions, with only a few traits demonstrating significant differences. Discriminant analysis of mixed-gender samples using a combination of variables did not distinguish between geographic groups within each sex. The multifactor approach slightly differentiated between samples when sexes were compared separately, but with much overlap. The continuous sampling method revealed no statistically significant relationship between geographic and metric variables across the distribution range. A weak latitudinal cline was observed in snout-vent length, with both sexes being larger in the south. Noticeable temperature-correlated intraspecific variability was found in both body and tail scale counts but not in head scalation features. Generally, both males and females demonstrate the same phenotype-environment correlation. The spatial variations in external morphology suggest that temperature conditions during early ontogenesis may induce quantitative changes in the scalation pattern of V. palaestinae.

关键词： Vipera palaestinae geographic variability scalation pattern temperature-dependent trends Viperidae

The role of miRNA in retinal ganglion cell health and disease

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Neural Regeneration Research 2022年第3期17卷 516-522页

作者： Ben Mead stanislav Tomarev School of Optometry and Vision Sciences Cardiff UniversityCardiffUK Section of Retinal Ganglion Cell Biology Laboratory of Retinal Cell and Molecular BiologyNational Eye InstituteNational Institutes of HealthBethesdaMDUSA

miRNA are short non-coding RNA responsible for the knockdown of proteins through their targeting and silencing of complimentary m RNA *** mi RNA landscape of a cell thus affects the levels of its proteins and has significant consequences to its *** in this mi RNA landscape have been implicated in a variety of neurodegenerative diseases and have also garnered interest as targets for *** ganglion cells are the sole projection neuron of the retina with their axons making up the optic *** are a focus of study not only for their importance in vision and the myriad of blinding diseases characterized by their dysfunction and loss,but also as a model of other central nervous system diseases such as spinal cord injury and traumatic brain *** review summarizes current knowledge on the role of mi RNA in retinal ganglion cell function,highlighting how perturbations can result in disease,and how modulating their abundance may provide a novel avenue of therapeutic research.

关键词： exosome extracellular vesicle glaucoma miRNA neurodegenerative disease optic neuropathy retina retinal ganglion cell

Immune and metabolic cross-links in the pathogenesis of comorbid non-alcoholic fatty liver disease

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World Journal of Gastroenterology 2023年第4期29卷 597-615页

作者： stanislav Kotlyarov Department of Nursing Ryazan State Medical UniversityRyazan 390026Russia

In recent years,there has been a steady growth of interest in non-alcoholic fatty liver disease(NAFLD),which is associated with negative epidemiological data on the prevalence of the disease and its clinical *** is closely related to the metabolic syndrome and these relationships are the subject of active research.A growing body of evidence shows cross-linkages between metabolic abnormalities and the innate immune system in the development and progression of *** links are bidirectional and largely still unclear,but a better understanding of them will improve the quality of diagnosis and management of *** addition,lipid metabolic disorders and the innate immune system link NAFLD with other diseases,such as atherosclerosis,which is of great clinical importance.

关键词： Non-alcoholic fatty liver disease Metabolism Lipid metabolism Lipid Fat Innate immune system Pathogenesis

Forty-five years of keratoprosthesis study and application at the Filatov Institute: a retrospective analysis of 1060 cases

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International Journal of Ophthalmology(English edition) 2013年第3期6卷 375-380页

作者： stanislav Iakymenko Department of Eye Burns Ophthalmic Plastic Surgery Keratoplasty and Keratoprosthesis the Filatov Institute of Eye Diseases and Tissue Therapy

AIM: To present results of the keratoprosthesis method used at The Filatov Institute of Eye Diseases and Tissue Therapy. ·METHODS: A retrospective case series analysis was used to describe the development of new types of keratoprostheses and methods of implantation as well as different ways of leukoma strengthening. ·RESULTS: Keratoprosthesis was performed in 1 060 eyes of 1 040 patients with leukomas of different etiology: burns, 725 eyes (68.4% ); trauma, 120 eyes (11.3% ); keratitis and ocular pemphigoid, 108 eyes (10.2% ); and bullous keratopathy, 107 eyes (10.1% ). Visual acuity before keratoprosthesis consisted of light perception in 962 eyes (92% ), and 98 eyes (8% ) had minimal visual acuity (1/200-1/50). Both eyes were blind (visual acuity less than 1/200) in 955 patients (91.8% ). The period of blindness varied from 1 to 52 years. As a result of keratoprosthesis, visual acuity of ≥1/200 was restored in 1 023 of 1 060 eyes (96.5%). Visual acuity of 20/200-20/20 was achieved in 716 eyes (67.5%). At the last follow-up visit visual acuity of ≥1/200 was preserved in 806 eyes (76%), visual acuity of 20/200-20/20 was measured in 583 of 1 060 eyes (55%) and good keratoprosthesis fixation in the cornea was achieved in 986 of 1 060 eyes (93%). The minimal follow-up was 12 months (range, 12 months to 37 years, median 5 years). · CONCLUSION: Our techniques of keratoprosthesis effectively restore vision in patients with leukomas that cannot be treated by optical corneal grafting.

关键词： artificial cornea corneal grafting keratoprosthesis leukoma

Implantation of Iakymenko keratoprosthesis in patients with severe ocular injury

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International Journal of Ophthalmology(English edition) 2012年第2期5卷 167-171页

作者： stanislav Iakymenko The Filatov Institute of Eye Disease and Tissue Therapy Odessa Ukraine

AIM: To present the results of implantation of Iakymenko keratoprosthesis in five patients with vascularized corneal leukoma caused by severe ocular injury. METHODS: Iakymenko keratoprosthesis was implanted into 5 eyes of 5 patients: 4 patients were suffered from chemical burns and 1 patient from explosive injury. The preoperative visual acuity ranged from light perception to hand motion. The implantation surgery was composed of two-stage procedures. The follow-up period was from 9 months to 11 years. The outcome measures were visual acuity, retention, and complications of the keratoprosthesis. RESULTS: Vision improvements were achieved in most patients. All keratoprosthesis were retained within the follow-up period. Corneal melting occurred in one patient and fibrous closure in another patient, both of which were successfully treated. Retinal detachment occurred in one patient after surgery. CONCLUSION: Iakymenko keratoprosthesis seems to be a promising alternative for the patients with severe corneal injury, but further investigation is needed to evaluate the role of Iakymenko keratoprosthesis.

关键词： Iakymenko keratoprosthesis visual rehabilitation complications

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

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

Tribological properties of the beetle leg joints

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Friction 2024年第12期12卷 2791-2807页

作者： Konstantin NADEIN Alexander KOVALEV stanislav N.GORB Functional Morphology and Biomechanics Zoological InstituteChristian-Albrechts University of KielAm Botanischen Garten 1-924118 KielGermany

Tribological properties of femoro-tibial leg joints in two beetles,darkling beetle Zophobas morio and Congo rose chafer Pachnoda marginata were *** low friction of 0.004 was revealed by the direct measurements in the *** is assumed that semi-solid lubricant functioning as in technical bearings is one of the leading factors of the friction *** of the surface texture and physical chemical properties(hydrophobicity)on the cuticle friction was *** of the surface texture to the tribological properties of contacting surfaces was examined by the measurement in the tribosystem“contacting surface/glass”.It is supposed that coefficient of friction(COF)decreases with decrease of surface *** the same time,no statistically significant correlation was found between the hydrophobicity of the surface and the value of the friction coefficient.

关键词： biotribology friction articulation contact angle surface texture lubrication

A Learning-based Control Framework for Fast and Accurate Manipulation of a Flexible Object

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Journal of Bionic Engineering 2024年第4期21卷 1761-1774页

作者： Junyi Wang Xiaofeng Xiong Silvia Tolu stanislav N.Gorb Department of Electrical and Photonics Engineering Technical University of DenmarkAnker Engelunds Vej 101Kongens LyngbyZealand2800Denmark SDU Biorobotics Mærsk Mc-Kinney Møller InstituteUniversity of Southern Denmark(SDU)Campusvej 55Odense MFunen5230Denmark Department Functional Morphology and Biomechanics Zoological InstituteUniversity of KielAm Botanischen Garten 1–9D-24118KielSchleswig-HolsteinGermany

This paper presents a learning-based control framework for fast(3 times of others).Besides,motion tracking errors are greatly reduced to 13.29 and 22.36 of constant impedance control by the OIAC of the proposed *** addition,the trajectory similarity between simulated and physical whips is *** presented framework provides a new method integrating data-driven and physics-based algorithms for controlling fast and accurate arm manipulation of a flexible object.

关键词： Deep reinforcement learning Deformable object manipulation Variable impedance control Sim2real Visual tracking