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In this paper the effect of particle shape and size on the mechanic behavior of glass-particle reinforcing Nylon matrix composite is evaluated. There are many parameters effecting on the composite such as types, size, position and shape of reinforcement material. Particle morphology has received enormous interest in particulate composite; small particles adhere strongly to the polymer, which leads to a strong reinforcing effect. The objective of this research is to investigate the influence of reinforcement shape and size with different volume fractions and for three packing (square, hexagonal and random) using finite element method. The composite is subject to unidirectional tensile loading. Numerical results are presented for a variety of particle shapes and size including circular, triangular, square and two distributions grouping these shapes together. The results show that the variation of the Von Mises and longitudinal stresses consistently increased when the shape of the reinforcement changed from triangle to square, distribution 1 and distribution 2 to circular in this order. [ABSTRACT FROM AUTHOR]

Background: The aim of this article was to study the circadian intraocular pressure (IOP)-related effects of ocular hypotensive medications using a contact lens sensor (CLS). Design: This is a university-based prospective, randomized, crossover trial. Participants: A total of 23 patients with primary open-angle glaucoma participated. Methods: Patients underwent ambulatory recording of IOP-related patterns for 24h in one eye during 3 monthly sessions using a CLS. Patients were untreated in session 1 (S1), were randomized to one of four classes of glaucoma drops for S2 and had a prostaglandin analogue add-on for S3. Main Outcome Measures: Changes in IOP-related patterns were defined using (i) slopes from wake/sitting to sleep/supine; (ii) cosinor rhythmometry modelling; and (iii) area under receiver operating curve (AUC) of sleep period. Results: Mean patient age was 63.8±11.8 years. Positive linear slopes were seen from wake/sitting to sleep/supine at S1 (17.1±14.2mVeq/h) and S2 (5.5±23.9mVeq/h) and negative slopes at S3 (-1.9±29.4mVeq/h) (S1-S2, P=0.01; S1-S3, P=0.02). In the prostaglandin group, slopes changed significantly with introduction of drops (S1-S2, P

This study explores the intricacies of employing two cooperative robotic manipulators for milling operations. Path planning, tool feed rate regulation, and cutting force management constitute essential elements in the milling process executed by these two collaborative robots. The two cooperative robots' milling process requires the coordination of path planning, cutting force management, and tool feed rate regulation. The path planning for the robotic system has been meticulously designed and seamlessly integrated with milling process expertise, while also adhering to the necessary technical specifications. This has been subsequently implemented on two cooperative robots featuring 3 Degrees of Freedom (3-DOF), utilizing the Staubli TX-90 robot model as a foundation. The milling of a typical workpiece by this robotic system is exemplified as a constrained optimization process. Regarding cooperative robot control, a method based on the Multiple Adaptive Neuro-Fuzzy Inference System (MANFIS) has been embraced. In order to validate the effectiveness of the presented approach, a comprehensive simulation has been conducted by using Matlab/SimMechanics software, and the results from this simulation have unequivocally substantiated the efficacy of the method. [ABSTRACT FROM AUTHOR]

Our work entitled improvement of the mechanical properties of a Z80WCV 18-04-01 high-speed steel grooving cutter (three sizes) by heat treatment, the latter can play an essential role in improving the mechanical and structural properties of grooving mills. The results obtained showed that the heat treatments allow to obtain a favorable microstructure, with a martensitic phase formation and a homogeneous distribution of carbides. These structural changes have led to an increase in the hardness, strength and durability of the milling cutters to be grooved in addition, it has been observed that the application of cumulative revenues has a significant impact on the mechanical and structural properties. The successive revenues favored the transformation of quenching martensite into tempering martensite and the elimination of residual austenite, leading to a gradual increase in hardness and wear resistance. [ABSTRACT FROM AUTHOR]

This paper proposes an inverse dynamics solution for two cooperative robots in a low depth milling application, by using the Levenberg-Marquardt algorithm. The objective is to achieve precise and coordinated control of the motions of the two robots working cooperatively to perform a milling task on a part. The proposed solution involves modeling the dynamics of the robots and their interactions, and formulating an optimization problem to obtain the forces on the workpiece. The proposed approach takes into account the kinematic and the dynamic constraints of the robots, as well as their interactions, in order to ensure smooth and coordinated motion. The Levenberg-Marquardt algorithm's effectiveness in achieving precise and synchronized motion and force control for a pair of collaborative robots during low-effort milling is validated through simulations conducted in MATLAB/SimMechanics. The simulation results confirm the robust performance of the proposed solution. This proposed approach shows potential for boosting the efficiency and the precision of collaborative milling tasks within industrial environments, ultimately resulting in improved manufacturing capabilities and increased productivity. Further experimental validation on a real robotic system is planned for future work. [ABSTRACT FROM AUTHOR]

This study investigates the response of small-scale length parameters and homogenization models of a simply supported nano-plate composed of functionally graded material. The natural frequency is presented for all cases, and the effect of different modes (Voigt, Reuss, LRVE, and Tamura), thickness ratio, and nonlocal parameter on the natural frequency is analyzed. The results show that the homogenization scheme is more influential in the vibrational response of FGM nanoplate with lower aspect ratios, and an increase in the small scale parameter causes a decrease in the natural frequency. To derive the governing equations and resolve them, the virtual work principle and Navier's model were employed. The accuracy of the proposed analytical model was verified by comparing the results with those obtained from other models available in the literature. [ABSTRACT FROM AUTHOR]

Some of the material demands in the advanced industries cannot be fulfilled by monolithic materials. Therefore, composite materials have been developed. The combination of desired properties of thermoplastics and glass particles (high strength and high modulus) is the aim of composites production Particles are becoming increasingly popular reinforcing elements in products made by injection molding. Particles reinforcement allows the polymer to be processed employing the same methods as those used for unreinforced polymers. The loads are not directly applied to the reinforcements, but they are applied to the matrix and some of the loads applied are transferred to the particles. The development of micromechanics equations for the particulate composites follows along the same lines as those for the short fiber reinforced composites. Particles are used to increase the strength or other properties of inexpensive materials during reinforcement with other matrix materials. The objective of this study is to analyse the particle breaking effect in composite made of nylon 66 (PA) matrix reinforced with glass particles, in which the particles diameters of 19.61, 26.15, 39.22 and 78.45 μm were used. A volume fraction of 20 % was assumed in each model. [ABSTRACT FROM AUTHOR]

Kaweh Mansouri,1 Felipe A Medeiros,2 Robert N Weinreb2 1Glaucoma Sector, Department of Ophthalmology, Geneva University Hospitals, Geneva, Switzerland; 2Hamilton Glaucoma Center and Department of Ophthalmology, University of California, San Diego, La Jolla, CA, USA Abstract: We report the results of repeated ambulatory continuous 24-hour intraocular pressure (IOP) monitoring with a contact lens sensor (CLS) in a glaucoma patient with ocular pain after ab interno trabeculotomy (Trabectome™) surgery. Our findings show that a combined prostaglandin–pilocarpine treatment reduced nighttime IOP peaks and relieved the patient’s symptoms. Keywords: 24-hour, Trabectome contact lens sensor, prostaglandin–pilocarpine treatment

"n Normal 0 false false false EN-US X-NONE AR-SA MicrosoftInternetExplorer4 /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-qformat:yes; mso-style-parent:""; mso-padding-alt:0in 5.4pt 0in 5.4pt; mso-para-margin:0in; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:11.0pt; font-family:"Calibri","sans-serif"; mso-ascii-font-family:Calibri; mso-ascii-theme-font:minor-latin; mso-fareast-font-family:"Times New Roman"; mso-fareast-theme-font:minor-fareast; mso-hansi-font-family:Calibri; mso-hansi-theme-font:minor-latin; mso-bidi-font-family:Arial; mso-bidi-theme-font:minor-bidi;} Background: Skin-derived precursors (SKPs) are a type of progenitor cells extracted from mammalian dermal tissue and can be differentiate to neural and mesodermal lineage in vitro. These cells can introduce an accessible autologos source of neural precursor cells for treatment of different neurodegenerative diseases. This research was done in order to set up isolation, culture, proliferation and differentiation of human skin derived precursors (hSKPs)."n"nMethods: Human foreskin samples were cut into smaller pieces and cultured in proliferation medium after enzymatic digestion. To induce neural differentiation, cells were cultured in neural differentiation medium after fifth passage. We used immunocytochemistry and RT-PCR for characterization of the cells. Neuron and glial cell differentiation potential was assessed by immunofloresence using specific antibodies. The experiments were carried out in triplicate."n"nResults: After differentiation, βΙΙΙ- tubulin and neurofilament-M positive cells were observed that are specific markers for neurons. Moreover, glial fibrillary acid protein (GFAP) and S100 positive cells were identified that are markers specifically express in glial cells. Detected neurons and glials were also confirmed by their morphologic characterizations."n"nConclusion: Our results demonstrated that skin-derived precursors obtained from human foreskin can exhibit neuronal and glial differentiation potential in vitro, depending on the protocols of induction.

"n Normal 0 false false false EN-US X-NONE AR-SA MicrosoftInternetExplorer4 /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-qformat:yes; mso-style-parent:""; mso-padding-alt:0in 5.4pt 0in 5.4pt; mso-para-margin:0in; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:11.0pt; font-family:"Calibri","sans-serif"; mso-ascii-font-family:Calibri; mso-ascii-theme-font:minor-latin; mso-fareast-font-family:"Times New Roman"; mso-fareast-theme-font:minor-fareast; mso-hansi-font-family:Calibri; mso-hansi-theme-font:minor-latin; mso-bidi-font-family:Arial; mso-bidi-theme-font:minor-bidi;} Background: Proteolytic enzymes, especially collagenases, are used for digestion of extracellular matrix, cell isolation and primary culture. Because of the problems in purification and low amount of collagenases in bacterial or animal sources, it is important to find new sources of the enzymes. So, in the present study actinidin, a plentiful protein in kiwifruit was purified and a mixture of actinidin and trypsin was applied to isolate rat aortic endothelial cells."n"nMethods: Aortic endothelial cells were isolated using digestion solution containing different concentrations of actinidin (from 2 to 16 mg/ml) and trypsin (0.3, 0.6, 1.2 and 2.4 mg/ml) in different times (from 15 to 90 minute). Isolated cells were cultured in DMEM culture medium. Isolated cells were identified by morphological characteristics and immunocytochemical staining; viability of separated cells was estimated by trypan blue exclusion test."n"nResults: Actinidin in concentration of 10 mg/ml with trypsin in concentration of 1.2 mg/ml for one hour could isolate rat aortic endothelial cells. In this condition the viability of cells was estimated 90%. Morphological and immunocytochemical charac-teristics confirmed the isolated cells as endothelial cells."n"nConclusion: The results showed that the mentioned mixture of actinidin and trypsin has not considerable toxic effects on separated cells and is a novel and suitable option for isolation of rat aortic endothelial cells.

To integrate the consideration of environmental issues in the design phase of a product eco-design is an ecological quality improvement and preventive approach of it while verifying that the resulting environmental gain is not at the expense of other environmental aspects and focusing on the preservation of its quality of use of its features or certain stages of its life cycle without losing the own global vision of eco-design. Following this vision, the use of bio-laden animal based polymers derived from a mode of production by implementing optimization practices respectful of natural resources sustainably, has become changing way of thinking largely replace the use of non-renewable resources for human activities, the depletion of fossil resources deposits and to fight against the impact of climate change generated by this practice. Our paper attempts to analyze first the mechanical behavior of a bio-load and then incorporated into a polymer material to test improved mechanical and thermal characteristics made to it after adding and optimizing subsequently, its use. This is a load in the form of powder or chips extracted from an animal sheath. Tensile tests are performed in a first step, in order to mechanically characterize the virgin material and eco-composite obtained after the combination, i.e. the maximum tensile strength, the relative deformation and the modulus of the elasticity, etc

"nBackground: Plasminogen has a central role in fibrinolyrtic system can activate through various activators (PAs) to its active form plasmin and perfoem its vital function that is fibrin clot lysis. Furthermore the fibrinolyrtic system plays a major role in angiogenesis. The fibrinolyrtic system activation control cell migration and invasion. In addition to this, plasmin regulates tumor growth. Monoclonal antibodies, as biological tools, play an important role in basic researches. "nMethods: In the first step the effects of antibodies on the activation of fibrinolyrtic system with PAs were evaluated with several methods including macroscopic observation, quantitative measurement of DD/E fragments by D-dimer assay and activation of plasminogen by S-2251 synthetic substrate (ELISA method), subsequently we studied the effect of antibodies on angiogenesis process in an in- vitro model. "nResults: Results showed that MC2B8 that is an inhibitor of plasminogen activation in presence of plasminogen activators can inhibit angiogenesis process: A1D12 that is against N-terminal domain of Glu-plasminogen, in addition to activation of fibrinolyrtic system in presence of plasminogen activators, can activate in vitro angiogenesis process. "nConclusion: Plasmin formation is a critical step in invasion and migration of endothelial cells to form new vessels. Plasmin directly participates in angiogenesis by direct fibrin and other matrix components degradation, and indirectly by activating matrix degrading metalloproteinase and angiogenic growth factors. According to the in- vitro results, MC2B8 and A1D12 monoclonal antibodies play roles in this process in a dose dependent manner.

Functionally graded materials (FGM) are a class of composites, in which the properties of the material gradually change over one or more Cartesian directions, the combination of which results in an assembly with higher performance than components taken separately. This class of composite materials has gained considerable attention in the engineering community, especially in high-temperature applications such as nuclear reactors, aerospace, and power generation industries. The aim of the current work is to study the influence of homogenization (idealization) models and thermal loads on static deflection behavior of sandwich functionally graded plate. Several micromechanical models have been employed to obtain the effective material properties of the two-phase FGM plate. The FGM plate is subjected to linear and no linear thermal loads. The integral theory used contains only four variable functions as against five in the case of other HSDTs. The governing equation are derived and resolved via virtual work principle and Navier's model. The accuracy of the proposed analytical model is confirmed by comparing the results with those given by others model existing in the literature. [ABSTRACT FROM AUTHOR]

The measurement based on the vision of periodic patterns by a remote camera is a more suitable solution for the control and characterization of micro robotic systems. In this way, we can take precise measurements without disturbing the measured objects and without the need for more devices and sensors that cause great confusion and clutter around the workspace. The technique of projection of the coded periodic patterns is perhaps effective and of good performance and especially in the case of a well calibrated system. Indeed, the question arises on the influence of the calibration on the results of measurement by this technique in terms of precision and uncertainty. Thus, the main purpose of this article is to study the influence of calibration on the measurement process, by deducing and calculating the committed error and the uncertainty rate. Based on an algorithm in MATLAB, we first create a coded periodic test pattern to which we apply a certain imposed displacement. Then, we project this pattern using a projection and reduction system on a digital camera which captures a photo and transmits it to a processing algorithm, which, in turn, calculates and deduces a value for the measured displacement. The repetition of this process occurs several times on the same imposed displacement (the same standard) to provide us with several measured values, this redundancy of the data allows us to draw a calibration curve and deduce several metrological parameters from our system of measure. [ABSTRACT FROM AUTHOR]