Survey of fish protective facilities at water withdrawal sites on the Snake and Columbia Rivers

Proliferation of water withdrawals and new pump intake and screen designs has occurred with the growth of irrigated agriculture along the Columbia and Snake Rivers. Concern for the protection of anadromous and resident fish populations resulted in formulation of a survey of the water withdrawal systems. The survey included distribution studies of juvenile fish near pump sites and field inspection of those sites to determine adequacy of screening for protection of fish. A total of 225 sites were inspected in 1979 and 1980, with a follow-up inspection of 95 sites in 1982. Results indicated a definite trend toward lack of concern for the condition of fish protective facilities. Only 4 out of 22 sites not meeting criteria in 1979 had been upgraded to acceptable conditions. Of more concern, 13 of the sites meeting criteria in 1979 were below criteria when reinspected in 1982. Some of the discrepancies included lack of protective screens, poorly maintained screens, and screens permitting excessive velocity that could result in impingement of larvae or small fish. A conclusion from these surveys is that if adequate protection for fish is to exist, screens for water withdrawals need to be properly installed, inspected, and maintained. (PDF file contains 40 pages.

Design of small Stirling dynamic isotope power system for robotic space missions

Design of a multihundred-watt Dynamic Isotope Power System (DIPS) based on the U.S. Department of Energy (DOE) General Purpose Heat Source (GPHS) and small (multihundred-watt) free-piston Stirling engine (FPSE) technology is being pursued as a potential lower cost alternative to radioisotope thermoelectric generators (RTG's). The design is targeted at the power needs of future unmanned deep space and planetary surface exploration missions ranging from scientific probes to Space Exploration Initiative precursor missions. Power level for these missions is less than a kilowatt. Unlike previous DIPS designs which were based on turbomachinery conversion (e.g. Brayton), this small Stirling DIPS can be advantageously scaled down to multihundred-watt unit size while preserving size and mass competitiveness with RTG's. Preliminary characterization of units in the output power ranges 200-600 We indicate that on an electrical watt basis the GPHS/small Stirling DIPS will be roughly equivalent to an advanced RTG in size and mass but require less than a third of the isotope inventory

Design of multihundredwatt DIPS for robotic space missions

Design of a dynamic isotope power system (DIPS) general purpose heat source (GPHS) and small free piston Stirling engine (FPSE) is being pursued as a potential lower cost alternative to radioisotope thermoelectric generators (RTG's). The design is targeted at the power needs of future unmanned deep space and planetary surface exploration missions ranging from scientific probes to SEI precursor missions. These are multihundredwatt missions. The incentive for any dynamic system is that it can save fuel which reduces cost and radiological hazard. However, unlike a conventional DIPS based on turbomachinery converions, the small Stirling DIPS can be advantageously scaled to multihundred watt unit size while preserving size and weight competitiveness with RTG's. Stirling conversion extends the range where dynamic systems are competitive to hundreds of watts (a power range not previously considered for dynamic systems). The challenge of course is to demonstrate reliability similar to RTG experience. Since the competative potential of FPSE as an isotope converter was first identified, work has focused on the feasibility of directly integrating GPHS with the Stirling heater head. Extensive thermal modeling of various radiatively coupled heat source/heater head geometries were performed using data furnished by the developers of FPSE and GPHS. The analysis indicates that, for the 1050 K heater head configurations considered, GPHS fuel clad temperatures remain within safe operating limits under all conditions including shutdown of one engine. Based on these results, preliminary characterizations of multihundred watt units were established

Hyperextended Scalar-Tensor Gravity

We study a general Scalar-Tensor Theory with an arbitrary coupling funtion $\omega (\phi )$ but also an arbitrary dependence of the ``gravitational constant'' $G(\phi )$ in the cases in which either one of them, or both, do not admit an analytical inverse, as in the hyperextended inflationary scenario. We present the full set of field equations and study their cosmological behavior. We show that different scalar-tensor theories can be grouped in classes with the same solution for the scalar field.Comment: latex file, To appear in Physical Review

Synthesis, optical properties, and microstructure of semiconductor nanocrystals formed by ion implantation

High-dose ion implantation, followed by annealing, has been shown to provide a versatile technique for creating semiconductor nanocrystals encapsulated in the surface region of a substrate material. The authors have successfully formed nanocrystalline precipitates from groups IV (Si, Ge, SiGe), III-V (GaAs, InAs, GaP, InP, GaN), and II-VI (CdS, CdSe, CdS{sub x}Se{sub 1{minus}x}, CdTe, ZnS, ZnSe) in fused silica, Al{sub 2}O{sub 3} and Si substrates. Representative examples will be presented in order to illustrate the synthesis, microstructure, and optical properties of the nanostructured composite systems. The optical spectra reveal blue-shifts in good agreement with theoretical estimates of size-dependent quantum-confinement energies of electrons and holes. When formed in crystalline substrates, the nanocrystal lattice structure and orientation can be reproducibly controlled by adjusting the implantation conditions

Analysis of radiation-induced cell death in head and neck squamous cell carcinoma and rat liver maintained in microfluidic devices

Objective The aim of this study was to investigate how head and neck squamous cell carcinoma (HNSCC) tissue biopsies maintained in a pseudo in vivo environment within a bespoke microfluidic device respond to radiation treatment. Study Design Feasibility study. Setting Tertiary referral center. Subjects and Methods Thirty-five patients with HNSCC were recruited, and liver tissue from 5 Wistar rats was obtained. A microfluidic device was used to maintain the tissue biopsy samples in a viable state. Rat liver was used to optimize the methodology. HNSCC was obtained from patients with T1-T3 laryngeal or oropharyngeal SCC; N1-N2 metastatic cervical lymph nodes were also obtained. Irradiation consisted of single doses of between 2 Gy and 40 Gy and a fractionated course of 5×2 Gy. Cell death was assessed in the tissue effluent using the soluble markers lactate dehydrogenase (LDH) and cytochrome c and in the tissue by immunohistochemical detection of cleaved cytokeratin18 (M30 antibody). Results A significant surge in LDH release was demonstrated in the rat liver after a single dose of 20 Gy; in HNSCC, it was seen after 40 Gy compared with the control. There was no significant difference in cytochrome c release after 5 Gy or 10 Gy. M30 demonstrated a dose-dependent increase in apoptotic index for a given increase in single-dose radiotherapy. There was a significant increase in apoptotic index between 1×2 Gy and 5×2 Gy. Conclusion M30 is a superior method compared with soluble markers in detecting low-dose radiation-induced cell death. This microfluidic technique can be used to assess radiation-induced cell death in HNSCC and therefore has the potential to be used to predict radiation response

Examining the Relationship Between Genetic Counselors’ Attitudes Toward Deaf People and the Genetic Counseling Session

Given the medical and cultural perspectives on deafness it is important to determine if genetic counselors’ attitudes toward deaf people can affect counseling sessions for deafness genes. One hundred fifty-eight genetic counselors recruited through the National Society of Genetic Counselors Listserv completed an online survey assessing attitudes toward deaf people and scenario-specific comfort levels discussing and offering genetic testing for deafness. Respondents with deaf/Deaf friends or who work in prenatal or pediatric settings had more positive attitudes toward deaf people than those without deaf/Deaf friends or those working in ‘other’ settings. More positive attitudes toward deaf people correlated with higher comfort level talking about genetic testing for the two scenarios involving culturally Deaf clients; and correlated with higher comfort level offering genetic testing to culturally Deaf clients wishing to have a deaf child. Attitudes and comfort level were not correlated in the scenarios involving hearing or non-culturally deaf clients. These results suggest that genetic counselors’ attitudes could affect information provision and the decision making process of culturally Deaf clients. Cultural sensitivity workshops in genetic counseling training programs that incorporate personal interactions with culturally Deaf individuals are recommended. Additional suggestions for fostering personal interactions are provided

Role of growth regulators in the bean hypocotyl hook opening response

The opening of the hypocotyl hook in bean seedlings is due to a rapid elongation of cells on the inner side of the hook elbow. Red light promotes hook opening by inducing this cell elongation.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/47488/1/425_2004_Article_BF00389364.pd

Origins of cattle on Chirikof Island, Alaska, elucidated from genome-wide SNP genotypes

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