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排序方式: 共有137条查询结果,搜索用时 15 毫秒
1.
An enantioselective synthesis of the (1'S,2'R)-dimethylheptyl cannabinoid side chain has been developed and employed in the synthesis of 11-hydroxy-(1'S,2'R)-dimethylheptyl-delta 8-THC (3). Pharmacology, in vivo and in vitro, indicate (3) to be one of the most potent traditional cannabinoids known.  相似文献   
2.
This paper provides an evaluation of the Scottish freedom of information regime in the modern denationalised environment. The authors conducted a pragmatic investigation by means of a real-world compliance inquiry which involved, among other things, the electronic submission of standardised requests for information to those local authority arm's-length external organisations which find themselves now subject to the provisions of the Freedom of Information (Scotland) Act 2002. A compliance matrix, with several response measures, recorded the progression and outcome of the requests sent to each named ‘public authority’. The article is also furnished with a contextual overview of the interaction between the home nation FOI regimes and private enterprise with a nod to contemporaneous events. In turn, the paper reveals several quagmires for the operational practicality of FOI in the privatised arena: a pronounced reminder of the difficulties associated with maintaining a functioning and practical FOI regime in light of a myriad of public service delivery models in the denationalised epoch.  相似文献   
3.
Spins of single donor atoms are attractive candidates for large scale quantum information processing in silicon. Formation of devices with a few qubits is crucial for validation of basic ideas and development of a scalable architecture. We describe our development of a single ion implantation technique for placement of single atoms into device structures. Collimated highly charged ion beams are aligned with a scanning probe microscope. Enhanced secondary electron emission due tohigh ion charge states (e.g., 31P13+, or 126Te33+)allows efficient detection of single ion impacts. Studies of electrical activation of low dose, low energy implants of 31P in silicon show a drastic effect of dopant segregation to the SiO2/Si interface,while Si3N4/Si retards 31P segregation. We discuss resolution limiting factors in ion placement, and process challenges forintegration of single atom arrays with control gates and single electron transistors. PACS: 03.67.Lx, 34.50.Dy, 85.35.Gv, 73.23, 61.72, 86.40.py, 07.79.-v  相似文献   
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5.
Doxorubicin is a highly effective chemotherapy agent used to treat many common malignancies. However, its use is limited by cardiotoxicity, and cumulative doses exponentially increase the risk of heart failure. To identify novel heart failure treatment targets, a zebrafish model of doxorubicin-induced cardiomyopathy was previously established for small-molecule screening. Using this model, several small molecules that prevent doxorubicin-induced cardiotoxicity both in zebrafish and in mouse models have previously been identified. In this study, exploration of doxorubicin cardiotoxicity is expanded by screening 2271 small molecules from a proprietary, target-annotated tool compound collection. It is found that 120 small molecules can prevent doxorubicin-induced cardiotoxicity, including 7 highly effective compounds. Of these, all seven exhibited inhibitory activity towards cytochrome P450 family 1 (CYP1). These results are consistent with previous findings, in which visnagin, a CYP1 inhibitor, also prevents doxorubicin-induced cardiotoxicity. Importantly, genetic mutation of cyp1a protected zebrafish against doxorubicin-induced cardiotoxicity phenotypes. Together, these results provide strong evidence that CYP1 is an important contributor to doxorubicin-induced cardiotoxicity and highlight the CYP1 pathway as a candidate therapeutic target for clinical cardioprotection.  相似文献   
6.
Convergence in electricity intensity is analyzed among a sample of IEA countries. Sigma-convergence (the narrowing of the distribution) and to a lesser degree gamma-convergence (movement within the distribution) are detected. However, electricity intensity convergence is less dramatic than energy intensity convergence. Convergence within the end-use sectors is more diverse: in terms of the rates, timing, extent, and ultimate modal structure of the distributions. Commercial electricity intensity has more recently converged toward a bell-shape distribution. By contrast, industry electricity intensity is largely converging toward two distinct groups of countries: one with relatively high electricity intensity and another one with relatively low electricity intensity. Different still is related residential electricity consumption per capita where a small group of countries has stopped growing; another group has slowed considerably, while a third group experienced rapid growth.  相似文献   
7.
Oocysts of C. parvum have been associated with several waterborne outbreaks of gastro-enteric disease. Currently, one of the main barriers to oocyst contamination of drinking waters is provided by sand-bed filtration. In this study an atomic force microscope (AFM) has been used to measure the force of interaction between oocysts of C. parvum and a model sand surface (silicate glass). The AFM force curves have been compared and contrasted with the corresponding electrical potentials obtained from electrophoretic measurements (zeta). It has been found that the surface of C. parvum oocysts possesses a hairy layer, most likely a result of surface proteins extending into solution. The hairy layer imposes a steric repulsion between the oocyst and sand surface, in addition to any electrostatic repulsion. The hairy layer collapsed to varying extents in the presence of dissolved calcium and dissolved organic carbon, indicating that the oocysts may be more readily adsorbed onto the model sand surface under these conditions. Conversely, as the two surfaces are pulled apart, the occasional attachment of oocyst surface proteins to the model sand surface can result in adhesion. The AFM results offer new insights into the oocyst surface of C. parvum, and the mechanism of interaction with model sand surfaces under conditions relevant to sand-bed filtration.  相似文献   
8.
Psychopathy is associated with abnormalities in attention and orienting. However, few studies have examined the neural systems underlying these processes. To address this issue, the authors recorded event-related potentials (ERPs) while 80 incarcerated men, classified as psychopathic or nonpsychopathic via the Hare Psychopathy Checklist-Revised (R. D. Hare, 1991, 2003), completed an auditory oddball task. Consistent with hypotheses, processing of targets elicited larger frontocentral negativities (N550) in psychopaths than in nonpsychopaths. Psychopaths also showed an enlarged N2 and reduced P3 during target detection. Similar ERP modulations have been reported in patients with amygdala and temporal lobe damage. The data are interpreted as supporting the hypothesis that psychopathy may be related to dysfunction of the paralimbic system--a system that includes parts of the temporal and frontal lobes. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
9.
Reliable, repeatable earthquake forecast is a subject surrounded by controversy and scepticism. What is clear is that reliable forecast would be a critical tool for effective earthquake disaster management. It is proposed that satellites and ground-based facilities may detect earthquake precursors in the ionosphere a few hours or days before the main shock. A low-cost 100 kg class satellite carrying a topside sounder is proposed, to make systematic measurements over seismically active zones. The mission aims to confirm or refute the hypothesis of ionospheric earthquake precursors, define the reliability and reproducibility, and enable further scientific understanding of their mechanisms.  相似文献   
10.
The U.S. Patent and Trademark Office has completed the initial installation of an automated search system to enable patent examiners to search the full text of U.S. patents issued since 1975. This represents a first step in its automation program. The development effort began in 1982 and will continue into the 1990s. The full text database structure, content and creation are described. Further enhancements of the automated search system, including additional text files and digital image fascimiles are planned by the end of 1986 and will continue in 1987.  相似文献   
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