Heliospheric plasma sheets

[1] As a high-beta feature on scales of hours or less, the heliospheric plasma sheet (HPS) encasing the heliospheric current sheet shows a high degree of variability. A study of 52 sector boundaries identified in electron pitch angle spectrograms in Wind data from 1995 reveals that only half concur with both high-beta plasma and current sheets, as required for an HPS. The remaining half lack either a plasma sheet or current sheet or both. A complementary study of 37 high-beta events reveals that only 5 contain sector boundaries while nearly all (34) contain local magnetic field reversals, however brief. We conclude that high-beta plasma sheets surround current sheets but that most of these current sheets are associated with fields turned back on themselves. The findings are consistent with the hypothesis that high-beta plasma sheets, both at and away from sector boundaries, are the heliospheric counterparts of the small coronal transients observed at the tips of helmet streamers, in which case the proposed mechanism for their release, interchange reconnection, could be responsible for the field inversions

The Design of the Monitoring System for the Thermal Effect of the Surry Nuclear Power Plant on the James River

The demand for electric power in the United States is expected to double every 10 years. As hydroelectric power plant sites reach their full capacity, the demand for electricity will be met by the development of fossil fuel and nuclear power plants. The average thermal efficiency of nuclear power plants is presently about 32%. Therefore, a significant amount of heat is not utilized. For large power plants, the once-through cooling method, in which water is withdrawn from an adjacent body of water and returned after being heated, is the most common one. However, the great amount of heat discharged into the water may result in changes in the physical and chemical properties as well as in the ecology due to the rise in temperature of the water. The objectives of this study is to determine the region of the James River estuary which will be affected by the thermal discharges of the Surry nuclear power plant located at Hog Island and the temperature distribution within that region. The area under study is shown in figure 1. The cooling water is pumped in from the James River at the right side of Hog Island and returned at the left side. The following is a progress report of the first year\u27s work on this project

Cellular Ability to Sense Spatial Gradients in the Presence of Multiple Competitive Ligands

Many eukaryotic and prokaryotic cells can exhibit remarkable sensing ability under small gradient of chemical compound. In this study, we approach this phenomenon by considering the contribution of multiple ligands to the chemical kinetics within Michaelis-Menten model. This work was inspired by the recent theoretical findings from Bo Hu et al. [Phys. Rev. Lett. 105, 048104 (2010)], our treatment with practical binding energies and chemical potential provides the results which are consistent with experimental observations.Comment: 5 pages, 4 figure

Effects of chronic exposure to low doses of trichloroethylene on steroid hormone and insulin levels in normal men.

The aim of this study was to examine the serum levels of insulin and some adrenal steroid hormones in men chronically exposed to low doses of trichloroethylene (TCE). A total of 85 workers participated in this study. Each worker had urine collected and analyzed for trichloroacetic acids (UTCA) on the same day that a blood sample was taken for analyses of serum testosterone, sex hormone-binding globulin (SHBG), androstenedione, cortisol, aldosterone, and insulin. The mean concentration of environmental TCE was 29.6 ppm and the mean UTCA was 22.4 mg/g creatinine (range 0.8-136.4). TCE exposure did not cause any significant changes to the adrenal steroid hormone productions. The results showed that UTCA was significantly correlated to serum insulin levels. Insulin and SHBG responded in tandem, with the highest levels found in workers exposed to TCE for less than 2 years; levels of both parameters were significantly lowered in those exposed for more than 2 years. A triphasic response in insulin levels to TCE, which depended on the duration of exposure, was noted. Initial exposure caused an acute rise in insulin levels. This was followed by a fall to normal levels in those exposed 2-4 years and then a slight rise in those exposed for more than 6 years. The mechanism for this pattern of response to TCE exposure is yet unknown

Entangled-State Cycles of Atomic Collective-Spin States

We study quantum trajectories of collective atomic spin states of $N$ effective two-level atoms driven with laser and cavity fields. We show that interesting ``entangled-state cycles'' arise probabilistically when the (Raman) transition rates between the two atomic levels are set equal. For odd (even) $N$, there are $(N+1)/2$ ($N/2$) possible cycles. During each cycle the $N$-qubit state switches, with each cavity photon emission, between the states $(|N/2,m>\pm |N/2,-m>)/\sqrt{2}$, where $|N/2,m>$ is a Dicke state in a rotated collective basis. The quantum number $m$ ($>0$), which distinguishes the particular cycle, is determined by the photon counting record and varies randomly from one trajectory to the next. For even $N$ it is also possible, under the same conditions, to prepare probabilistically (but in steady state) the Dicke state $|N/2,0>$, i.e., an $N$-qubit state with $N/2$ excitations, which is of particular interest in the context of multipartite entanglement.Comment: 10 pages, 9 figure

Socio-economic Determinants of Cassava Production in Benue State, Nigeria.

The study examined the determinants of cassava production in Benue State Nigeria. A total of 180 farmers were selected across the state using multi-stage sampling technique. Data, which comprised information on the socio-economic characteristics and other quantitative variables relevant to the study, were collected using a well structured questionnaire and personal interviews. The social- economic characteristics were analyzed using descriptive statistics such as percentages and frequencies; simple multiple regression technique was used to analyze the production functions of cassava farmers. The results obtained revealed that R2 value was 0.419 indicating that 41.9% of variation in cassava production was accounted for by the variables considered in the study. Specifically, age of the farmers, occupation, household size, farming experience, level of education of farmers, farms size and fertilizer input where all significant and are important variables that affected the production of cassava in the study area. Given the enormous potential of cassava production in the study area, it has become so imperative that youths be encourage to participate effectively in cassava production, seeing that majority of the farmers are aged and will retire from active farming. This is to ensure food security. Effective structure should be put in place for the input and credit facilities provided by the government, this will ensure that these facilities get to those who need it and will in turn help the farmers expand their production. This study, although base in Benue State, may have implications for other States with similar situation. This will help the state meet self-sufficiency in food production and so be able to feed her teeming population

Gene sh e ginandromorfia em inflorescências masculinas de híbridos F1 entre o caiaué e o dendezeiro.

Neste estudo, foi analisada a relação entre o gene sh (gene da espessura do endocarpo) e a ocorrência da ginadromorfia nos HIE. Foram analisados três tipos de cruzamentos: 12 cruzamentos de caiaué com dendezeiro-dura, homozigoto sh+sh+ (C × D); 11 de caiaué com dendezeiro pisífera, homozigoto sh-sh-(C × P), e 15 de caiaué com dendezeiro-tenera, heterozigoto sh+sh- (C × T), com 10 a 13 plantas por cruzamento. A ocorrência de inflorescências ginandromorfas foi avaliada durante um ano