50,051 research outputs found
Comparative Study of Life Histories, Laboratory Rearing, and Immature Stages of \u3ci\u3eEuschistus Servus\u3c/i\u3e and \u3ci\u3eEuschistus Variolarius\u3c/i\u3e (Hemiptera: Pentatomidae)
A comparative study was conducted of the field life histories of Euschistus servus and E. varialarius in southern Illinois, their life cycles under controlled laboratory conditions, and their immature stages.
The results indicate that E. servus is bivoltine and E. variolarius is univoltine. Adults of both species emerged from overwintering sites during early April, began feeding and copulating on leaves of common mullein (Verbascum thapsus) and surrounding vegetation, and reproduced shortly thereafter. Neither eggs and first instars of either species, nor second instars of E. variolarius, were collected in the field. Seasonal occurrences of the adults and subsequent immature stages are discussed for each species. No individuals were found after the first week of November.
Both species were reared on green beans (Phaseolus vulgaris) under a 16L:8D photoperiod and constant temperature of 23 Ā± 0.06Ā° C. The incubation period averaged 5.8 days for E. servus and 5.4 days for E. variolanus. Durations of the 5 subsequent stadia averaged, respectively, 5, 6, 6.7, 9.3, and 11.5 days for E. servus, and 4.9,5.7,7.8,9.7, and 13.3 days for E. varialarius. Comparisons of incubation period and stadia between the two species showed that only the stadia for the first instars were not statistically different. Total developmental period was longer for E. varialarius than for E. servus.
The external anatomy of the egg and each of the five nymphal instars is described for each species
Spark Ignition Measurements in Jet A: part II
An improved system for measuring the ignition energy of liquid fuel was built to perform experiments on aviation kerosene (Jet A). Compared to a previously used system (Shepherd et al. 1998), the present vessel has a more uniform temperature which can be held constant for long periods of time. This ensures thermal equilibrium of the liquid fuel and the vapor inside the vessel. A capacitive spark discharge circuit was used to generate damped sparks and an arrangement of resistors and measurement probes recorded the voltage and current histories during the discharge. This permitted measurement of the energy dissipated in the spark, providing a more reliable, quantitative measure of the ignition spark strength. With this improved system, the ignition energy of Jet A was measured at temperatures from 35C to 50C pressures from 0.300 bar (ambient pressure at 30 kft) to 0.986 bar (ambient pressure near sea level), mass-volume ratios down to 3 kg/m^3, with sparks ranging from 10 mJ to 0.3 J. Special fuel blends with flash points (Tfp) from 29C to 73.5C were also tested. The statistical properties of the ignition threshold energy were investigated using techniques developed for high-explosive testing.
Ignition energy measurements at 0.585 bar with high mass-volume ratios (also referred to as mass loadings) showed that the trend of the dependence of ignition energy on temperature was similar for tests using the stored capacitive energy and the measured spark energy. The ignition energy was generally lower with the measured spark energy than with the stored spark energy. The present ignition energy system was capable of clearly resolving the difference in ignition energy between low and high mass-volume ratios. The ignition energy vs. temperature curve for 3 kg/m^3 was shifted approximately 5C higher than the curve for high mass-volume ratios of 35 kg/m^3 or 200 kg/m^3. The ignition energy was subsequently found to depend primarily on the fuel-air mass ratio of the mixture, although systematic effects of the vapor composition are also evident. As expected, the ignition energy increased when the initial pressure was raised from 0.585 bar to 0.986 bar, and decreased when the pressure was decreased to 0.3 bar. Finally, tests on special fuels having flash points different from that of commercial Jet A showed that the minimum ignition temperature at a spark energy of about 0.3 J and a pressure of 0.986 bar depends linearly on the flash point of the fuel
African American English And Urban Literature: Creating Culturally Caring Classrooms
Language and literacy are a means of delivering care through consideration of studentsā home culture; however, a cultural mismatch between the predominantly white, female educator population and the diverse urban student population is reflected in language and literacy instruction. Urban curricula often fail to incorporate culturally relevant literature, in part due to a dearth of texts that reflect student experiences. Dialectal differences between African American English (AAE) and Mainstream American English (MAE) and a history of racism have attached a reformatory stigma to AAE and its speakers. The authors assert that language and literacy instruction that validates childrenās lived experience mediates this hegemony, leads to empathetic relationships between teachers and students of different cultural backgrounds, and promotes academic success. This paper seeks to 1) dissect the relationship between academic achievement and affirmation of student culture through language and literacy instruction, 2) enumerate classroom strategies that empower students and foster the development of self-efficacy 3) identify ways teachers might weave value for diversity in language and literacy into a pedagogy of care for urban classrooms
The Efficacy of the Integrated Child Development Services in Perspective to Nutritional Condition and Growth Development
A survey was conducted to assess the nutritional status of children (0-6 years) among 40 Anganwadis in 4 districts of Kerala State registered under the ICDS scheme. A self- prepared structured interview schedule was used. To get the qualitative information of the study anthropometric measures include height and weight were used for assessing nutritional status of the children. The stepwise analysis of two variables height for age and weight for age was applicable on the basis of Waterlow\u27s and Gomez\u27 classification. To examine the relationship between nutritional status of the child and selected variable that affects nutritional status of children, Chi-square test was employed. Based on Gomez\u27 classification, out of 400 children, only 300 (75.0%) of children received supplementary nutrition through ICDS out of which 250 (62.5%) children were normal while 50 (12.5%) were underweight. Based on Waterlow\u27s classification out of 400 children, only 290 (72.5%) of children received supplementary nutrition through ICDS out of these children 200 (50 %) were normal while 90 (22.5%) were stunted. It can thus be concluded that majority of children were normal who received supplementary nutrition through ICDS
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