2,399 research outputs found

    Residential photovoltaic module and array requirements study

    Get PDF
    Design requirements for photovoltaic modules and arrays used in residential applications were identified. Building codes and referenced standards were reviewed for their applicability to residential photovoltaic array installations. Four installation types were identified - integral (replaces roofing), direct (mounted on top of roofing), stand-off (mounted away from roofing), and rack (for flat or low slope roofs, or ground mounted). Installation costs were developed for these mounting types as a function of panel/module size. Studies were performed to identify optimum module shapes and sizes and operating voltage cost drivers. It is concluded that there are no perceived major obstacles to the use of photovoltaic modules in residential arrays. However, there is no applicable building code category for residential photovoltaic modules and arrays and additional work with standards writing organizations is needed to develop residential module and array requirements

    Loose mechanochemical coupling of molecular motors

    Full text link
    In living cells, molecular motors convert chemical energy into mechanical work. Its thermodynamic energy efficiency, i.e. the ratio of output mechanical work to input chemical energy, is usually high. However, using two-state models, we found the motion of molecular motors is loosely coupled to the chemical cycle. Only part of the input energy can be converted into mechanical work. Others is dissipated into environment during substeps without contributions to the macro scale unidirectional movement

    Residential photovoltaic module and array requirements study, appendices

    Get PDF
    Regional building code variations, federal and city codes, and the national electric code are reviewed for their possible effects on the design of photovoltaic modules. Problems that photovoltaic arrays may impose on the insurability of residences are also discussed. Mounting configurations are developed for the modules, and grounding, wiring, terminal, and voltage requirements are established. Installation and materials costs are presented along with performance criteria

    USCID fourth international conference

    Get PDF
    Presented at the Role of irrigation and drainage in a sustainable future: USCID fourth international conference on irrigation and drainage on October 3-6, 2007 in Sacramento, California.Salt management is a critical component of irrigated agriculture in arid regions. Successful crop production cannot be sustained without maintaining an acceptable level of salinity in the root zone. This requires drainage and a location to dispose drainage water, particularly, the salts it contains, which degrade the quality of receiving water bodies. Despite the need to generate drainage water to sustain productivity, many irrigation schemes have been designed and constructed with insufficient attention to drainage, to appropriate re-use or disposal of saline drainage water, and to salt disposal in general. To control the negative effects of drainage water disposal, state and federal agencies in several countries now are placing regulations on the discharge of saline drainage water into rivers. As a result, many farmers have implemented irrigation and crop management practices that reduce drainage volumes. Farmers and technical specialists also are examining water treatment schemes to remove salt or dispose of saline drainage water in evaporation basins or in underlying groundwater. We propose that the responsibility for salt management be combined with the irrigation rights of farmers. This approach will focus farmers' attention on salt management and motivate water delivery agencies and farmers to seek efficient methods for reducing the amount of salt needing disposal and to determine methods of disposing salt in ways that are environmentally acceptable

    OCULAR CHANGES IN MONGOLISM

    Full text link
    Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/75455/1/j.1749-6632.1970.tb39372.x.pd

    The stimulating effects of ethanol on ventral tegmental area dopamine neurons projecting to the ventral pallidum and medial prefrontal cortex in female Wistar rats: regional difference and involvement of serotonin-3 receptors

    Get PDF
    RATIONALE: The ventral tegmental area (VTA) mediates the local stimulating effects of ethanol (EtOH) in a region-dependent manner, with EtOH administration in the posterior but not anterior VTA stimulating the mesolimbic system. The serotonin-3 (5-HT(3)) receptor has been involved in the effects of EtOH on the mesolimbic system. OBJECTIVES: The current study tested the hypothesis that EtOH would stimulate mesopallidal and mesocortical dopamine neurons in the posterior but not anterior VTA and that the stimulating effects of EtOH in the VTA would involve activation of local 5-HT(3) receptors. METHODS: Wistar female rats were surgically implanted with two cannulae, one in one sub-region of the VTA for microinjection and the other in the ventral pallidum (VP) or medial prefrontal cortex (mPFC) for microdialysis. Artificial cerebrospinal fluid or EtOH (200 mg%; 44 mM) was microinjected in the anterior or posterior VTA, and extracellular dopamine was measured in the VP or mPFC with microdialysis-HPLC. RESULTS: EtOH injections in the posterior but not anterior VTA significantly increased extracellular dopamine levels in the VP and mPFC. Co-injections of the 5-HT(3) receptor antagonist ICS-205,930 with EtOH in the posterior VTA significantly reduced the effects of EtOH on extracellular dopamine levels in the VP and mPFC. CONCLUSIONS: The results indicate that posterior VTA dopamine neurons projecting to the VP and mPFC are stimulated by local administration of EtOH and that the local stimulating effects of EtOH are mediated, at least in part, by 5-HT(3) receptors

    CB1 Receptors Regulate Alcohol-Seeking Behavior and Alcohol Self-administration of Female Alcohol-Preferring (P) Rats

    Get PDF
    Rationale The endogenous cannabinoid (CB) system mediates a number of behaviors associated with drug-seeking and drug self-administration. In this study the effects of CB1 receptor manipulations on operant ethanol (EtOH) responding during EtOH-seeking, EtOH- relapse as well as on-going EtOH self-administration were determined. Methods Alcohol-preferring (P) rats were trained in 2-lever operant chambers to self-administer 15% EtOH (v/v) and water on a concurrent fixed-ratio 5 – fixed-ratio 1 (FR5-FR1) schedule of reinforcement in daily 1-hr sessions. After 10 weeks, rats underwent 7 extinction sessions, followed by 2 weeks in their home cages without access to EtOH or operant chambers. Rats were then returned to the operant chambers for testing of EtOH-seeking behavior (no EtOH present) for 4 sessions. After a week in their home cages following the EtOH-seeking test, rats were returned to the operant chambers with access to EtOH and water (relapse). Rats were then maintained in the operant chambers for daily 1-hr sessions with access to 15% EtOH and water for several weeks. Results The CB1 receptor antagonist (SR141716A), at doses of 1 and 2 mg/kg, i.p. reduced EtOH-seeking and transiently reduced EtOH self-administration during relapse and maintenance. Conversely, treatment with the CB1 receptor agonist CP, 55-940, at doses of 1 and 10 μg/kg i.p., increased EtOH-seeking and EtOH self-administration during relapse. Conclusions The results of this study demonstrate that activation of CB1 receptors are involved in regulating EtOH-seeking as well as the reinforcing effects of EtOH under relapse and on-going self-administration conditions
    • …
    corecore