The efficiency of Amblyseius swirskii in control of Tetranychus urticae and Trialeurodes vaporariorum is affected by various factors.

Amblyseius swirskii Athias-Henriot is a well-known predator that is used for controlling the population of two-spotted spider mites (TSSM), Tetranychus urticae Koch, and greenhouse whitefly (GHWF), Trialeurodes vaporariorum Westwood, in strawberry greenhouses. To find the effective factors that influence the efficiency of this predator, the predation rates of A. swirskii fed on (Ι) TSSM in the presence and absence of the pollen, webbing, and GHWF, as well as on (II) GHWF in the presence and absence of the pollen, and GHWF-produced honeydew were determined. Furthermore, developmental time, fecundity, and population growth rate of this predator under the same conditions were measured. Our results showed that A. swirskii was able to reduce TSSM population, while the spider mite webbing had an adverse effect on the performance of the predator. Therefore, the presence of the predator population at the time of the infestation is crucial to the success of biological control. It can be concluded that the alternative food sources such as pollen and GHWF-produced honeydew play an important role in maintaining the predator population in the absence of pests. Moreover, the results indicate that using the pollen and another pest along with the target pest can promote the predator density. A. swirskii consumed lower numbers of TSSM when concurrently offered with GHWF and/or maize pollen, and lower numbers of GHWF in the presence of pollen. On the other hand, in the presence of alternative food or alternative prey, the fecundity of the predator was much higher.

Interplay of water and reactive elements in oxidation of alumina-forming alloys.

High-temperature alloys are crucial to many important technologies that underpin our civilization. All these materials rely on forming an external oxide layer (scale) for corrosion protection. Despite decades of research on oxide scale growth, many open questions remain, including the crucial role of the so-called reactive elements and water. Here, we reveal the hitherto unknown interplay between reactive elements and water during alumina scale growth, causing a metastable 'messy' nano-structured alumina layer to form. We propose that reactive-element-decorated, hydroxylated interfaces between alumina nanograins enable water to access an inner cathode in the bottom of the scale, at odds with the established scale growth scenario. As evidence, hydride-nanodomains and reactive element/hydrogen (deuterium) co-variation are observed in the alumina scale. The defect-rich alumina subsequently recrystallizes to form a protective scale. First-principles modelling is also performed to validate the RE effect. Our findings open up promising avenues in oxidation research and suggest ways to improve alloy properties.

On the capability of in-situ exposure in an environmental scanning electron microscope for investigating the atmospheric corrosion of magnesium.

The feasibility of environmental scanning electron microscope (ESEM) in studying the atmospheric corrosion behavior of 99.97% Mg was investigated. For reference, ex-situ exposure was performed. A model system was designed by spraying few salt particles on the metal surface and further promoting the corrosion process using platinum (Pt) deposition in the form of 1×1×1 µm(3) dots around the salt particles to create strong artificial cathodic sites. The results showed that the electron beam play a significant role in the corrosion process of scanned regions. This was attributed to the irradiation damage occurring on the metal surface during the ESEM in-situ experiment. After achieving to a reliable process route, in a successful attempt, the morphology and composition of the corrosion products formed in-situ in the ESEM were in agreement with those of the sample exposed ex-situ.

Could oral administration of immunoglobulin reduce diarrheal severity in common variable immunodeficiency?

No disponible

Cardiovascular risk factors in an Iranian urban population: Tehran lipid and glucose study (phase 1).

OBJECTIVES: Coronary artery disease is becoming more prevalent in developing countries, particularly in urban areas. This study was conducted to determine the prevalence of cardiovascular risk factors among Tehran urban population. METHODS: The prevalence and distribution of high blood pressure, cigarette smoking, dyslipoproteinemia, diabetes mellitus, and obesity was determined in 15,005 subjects, aged three years and over, selected by cluster random sampling in Tehran urban district-13 between February 1999 to August 2001. Total energy intake, percent of energy derived from protein, carbohydrate, and fat were assessed in a subsidiary of 1,474 persons by means of two 24-hour dietary recalls. RESULTS: In adults, 78% of men and 80% of women presented at least one CVD risk factor. The percentage of adult women with two or more risk factors was significantly greater than the one for men. Prevalence of DM, hypertension, obesity, high TC, low HDL, high TGs, and smoking was 9.8, 20.4, 14.4, 19.3, 32, 5.3, and 22.3%, respectively. In children and adolescents, two or more CVD risk factors were found in 9% of boys and 7% of girls. Prevalence of hypertension, obesity, high TC, low HDL, and high TGs, was 12.7, 5.2, 5.1, 10.2, and 5%, respectively. The mean percentage values of energy intake derived from carbohydrate, protein, and fat were 57.8 +/- 6.9, 11.1 +/- 1.8, and 30.9 +/- 7.2, respectively. CONCLUSION: The prevalence of cardiovascular risk factors among Tehran urban population is high; particularly of high total cholesterol, low HDL cholesterol levels, and high waist to hip ratio. An effective strategy for life style modification is a cornerstone of a population approach to the cardiovascular risk factors. Moreover, these results will serve as a baseline for assessment of future trends in the risk factors studied.