اندازه‌گیری پرتو گاما در زمینه‌های مختلف تحقیقاتی نیازمند آشکارسازهای کارآمد است. زمینه دزیمتری فوتون آشکارساز جرقه‌ای NaI(Tl) به عنوان یکی از سوسوزن معدنی (غیرآلی)، علت دارا بودن مقدار بالای نور خروجی بسیار حایز اهمیت این پژوهش سعی گردیده است، با کمک کد مونت‌کارلو (MCNPX) مقدمات مشخصه‌یابی توسط و بهره‌گیری روش‌های متفاوت محاسبه دز (تالی‌های 6F، 4*F، 6+F 8*F) انجام شود. طور معمول، یک تابش (شمار...

One of the fundamental concepts of integrated pest management is that each pest species has a definable relationship in terms of damage to the plant or animal host that it attacks. This relationship is often referred to as the damage curve (Fig. 1), which is often determined relative to yield loss. This damage curve can take several forms, but was summarized by Higley and Peterson as having a t...

We examine regulations for managing pest resistance to pesticide varieties in a temporally and spatially explicit framework. We compare the performance of the EPA’s mandatory refuges and a tax (or subsidy) on the pesticide variety under several biological assumptions on pest mobility and the heterogeneity of farmers’ pest vulnerability. We find that only the tax (or subsidy) restores efficiency...

Many existing pest control models, which control pests by releasing natural enemies, neglect the effect that natural enemies may get killed. From this point of view, we formulate a pest control model with stage structure for the pest with constant maturation time delay through-stage time delay and periodic releasing natural enemies and natural enemies killed at different fixed time and perform ...

Vascular injury increases nitric oxide (NO) levels, and this effect may play a counterregulatory role in neointima formation, by decreasing vascular smooth muscle cell motility. However, the mechanisms underlying this effect are not well established. We tested the hypothesis that NO decreases cell motility by increasing the activity of a protein tyrosine phosphatase (PTP), PTP-PEST, in cultured...

Pest insects pose a significant threat to food production worldwide resulting in annual losses worth hundreds of billions of dollars. Pest control attempts to prevent pest outbreaks that could otherwise destroy a sward. It is good practice in integrated pest management to recommend control actions (usually pesticides application) only when the pest density exceeds a certain threshold. Accurate ...

An important step in carcinoma progression is loss of cell-cell adhesion leading to increased invasion and metastasis. We show here that the protein tyrosine phosphatase, PTP-PEST, is a critical regulator of cell-cell junction integrity and epithelial cell motility. Using colon carcinoma cells, we show that the expression level of PTP-PEST regulates cell motility. Either transient small interfe...