یکی از جذاب ترین روش های ماشینکاری مدرن، تخلیه الکتریکی است که در اواخر دهه 1960 معرفی شد. با سیم کاربردهای مختلفی دارد، جمله دقت بالا تمام مواد رسانا مانند فلزات، آلیاژهای فلزی، گرافیت و سرامیک همچنین صنایع هوافضا، خودروسازی سایر صنایع. به منظور افزایش سرعت کاهش زبری سطح عرض شکاف، پارامترهای برش بهینه نقش مهمی انتخاب خروجی دارند. این مطالعه، ورودی (دبی، مدت پالس، فرکانس سیم، کشش جریان دی الکتر...

سفید­بالک گلخانهTrialeurodes vaporariorum Westwood یکی از آفات مهم­ سبزی، صیفی و گیاهان زینتی می­باشد. در کنترل این آفت، یافتن راهکارهای جایگزین به ­منظور کاهش اثرات سوء ناشی مصرف بی­رویه آفت­کش­های شیمیایی ضروری بنابراین پژوهش، اثر زیر­کشندگی (LC20) سه فرمولاسیون چریش (Azadirachta indica A. Juss) شامل نیم­بسیدین®، نیم­آزال® کوفا® روی سفید‌‌بالک گلخانه مورد بررسی قرار گرفت. آزمایش­ها با شرایط ن...

conclusions the study findings indicate that short-term exercises had no significant effect on the ratio of vmo to vl muscle fiber angles in patients with pfps. results there were no significant differences in the muscle strength and fiber angle of the vmo, vl oblique and longus muscles after training between the control and experimental groups (p > 0.05). patients and methods thirty-five subje...

Objective: To compare average electromyogram (EMG) activity of the vastus medialis obliquus (VMO) and vastus lateralis (VL) during straight-leg raise (SLR) and knee extension (KE) with the hip in neutral and lateral rotation. Design: 1  4 factorial repeated-measures. Setting: Laboratory. Participants: 13 male college students. Intervention: SLR with hip flexed at 40°, in neutral position, and ...

Background: Imbalance between the vastus medialis oblique (VMO) muscle and the vastus lateralis oblique (VTO) Vastus lateralis has been thought to be a primary cause of abnormal patellar tracking, possibly leading to patellofemoral pain syndrome (PFPS). Objectives: The purpose of this study was to investigate the effect of quadriceps muscle strengthening exercises on the ratio of VMO to VL obli...

Patellofemoral pain (PFP) is thought to be related to patellar maltracking due to imbalances in the knee extensor. However, no study has evaluated the in vivo biomechanical properties of the quadriceps tendon in PFP syndrome. Our purpose was to compare the biomechanical properties of the quadriceps tendons in vivo and noninvasively in patients with PFP syndrome to those of control subjects. The...

BACKGROUND AND PURPOSE Inappropriate neural control of the quadriceps femoris muscle group has been implicated in patellofemoral pain syndrome (PFPS). This study investigated the timing of initial electromyographic (EMG) activity of the vastus medialis oblique muscle (VMO) and the vastus lateralis muscle (VL) in asymptomatic subjects and subjects with PFPS during reflex and voluntary muscle act...

OBJECTIVE To determine if the combined isometric contractions of knee extension/hip adduction and knee extension/hip abduction will elicit a different quadriceps and gluteus medius electromyographic (EMG) pattern as compared to isometric contraction of a uniplanar knee extension exercise. METHODS Eight healthy young adult volunteers without history of knee or quadriceps injury participated. S...