A rapid screening method for amber fla mutants of E. coli was devised and many mutants were obtained. In addition, strains with deletions of the fla genes in the his-uvrC region were isolated from high-temperature survivors of a lambda cI857 lysogen in which the prophage is located between his and fla. Utilizing these mutants, eleven fla genes (I--XI) and one hag gene were identified in the his...

Levi McNeil, Sookmyung Women’s University Previous research suggests that the affordances (van Lier, 2000) of asynchronous computer-mediated communication (ACMC) environments help reduce foreign language anxiety (FLA). However, FLA is rarely the focus of these studies and research has not adequately addressed the relationship between FLA and the affordances that students use. This study explore...

Two variants of Campylobacter jejuni IN1 differing in the expression of flagella, IN1 (Fla+ Mot+, wild type) and IN1-NM (Fla- Mot-), were tested for their ability to establish infection in adult hamsters. Animals were challenged intracecally with 2 X 10(9) to 5 X 10(10) CFU and monitored for evidence of infection. None of the challenged animals developed illness. There was a significant differe...

Several species of Legionella cause Legionnaires' disease (LD). Infection may occur through inhalation of Legionella or amoebal vesicles. The reservoirs of Legionella are water, soil, potting soil and compost. Some species of free-living amoebae (FLA) that are naturally present in water and soil were described as hosts for Legionella. This study aimed to understand whether or not the composting...

سابقه و هدف: به ­دلیل توسعه رشد جمعیت انسان، نیاز انسان منابع ضروری افزایش یافته است. فعالیت‌های مربوط صنایع همچنین کشاورزی به­ طور گسترده‌ای زمین‌های را آلوده کرده ترکیبات نفتی فلزات سنگین هر دو از آلاینده‌های رایج موجود در خاک‌هایی هستند که با فاضلاب تصفیه نشده آبیاری شده‌اند سلامت محیط زیست خطر مواجه می‌کنند. آلودگی خاک می‌تواند سبب کاهش امکان زراعت، نهایت تولید غذا برای شود. جنوب شهر تهران ...