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991.
Throughout his distinguished career of over 40 years, Robin Hochstrasser has made significant contributions to several areas of science in the fields of chemical and biochemical physics. He has been at the forefront and made fundamental contributions to the fields of photochemistry, solid-state chemistry, ultra-fast laser spectroscopies, and protein dynamics. He has been a prolific researcher, producing over 560 publications. His work has been characterized by experts in the fields as “a constant stream of experiments of lasting significance” (J. Phys. Chem. 100 (1996) 11791).Robin began his career in the 1960s using a variety of magnetic and electric field measurements to study crystals at low temperatures to understand spin quantization in solids and electron exchanged-mediated energy transfer. This work, described as a “classic contribution” (J. Phys. Chem. 100 (1996) 11791) was the basis for much of the subsequent experimental and theoretical work on the effect of magnetic fields on molecular spectra and on the measurements of dipole moments.In the late 1970s, Robin recognized the power of laser technology for the study of molecules and soon became a leader in the field investigating solid, gas phase, and condensed phase systems. He developed and applied various ultra-fast laser techniques to study the structure and dynamics of complex molecules in liquid phase, chemical, and biochemical reactions. He made seminal contributions to the development of two-dimensional infrared spectroscopy (2D IR) on a time scale of a picosecond or less. This 2D IR spectroscopy measures coupling between two functional groups in a large molecule and can thus be used to measure distances, as for example, two amide carbonyl groups in a peptide molecule. On the ultra-fast timescale, one application of 2D IR is to gain information on the rate of protein folding and unfolding in solution. Some of Robin's greatest contributions to understanding biomolecules are said to be in the experimental studies on the picosecond and femtosecond dynamics of heme proteins. Using techniques he developed he was able to observe the interactions of oxygen, carbon monoxide, and nitric oxide with hemoglobin inside the protein.  相似文献   
992.
Metabolic abnormalities were investigated in 44 stone patients with first time (group 1) and 56 with 2 times stone formation (group 2), and in 25 normal individuals. 24hr urine was analysed spectrophotometrically for oxalate, calcium, magnesium, citrate, uric acid, phosphate and creatinine. Hypocitraturia and hyperoxaluria were the common abnormalities in the stone formers. Stone patients had significantly higher urinary oxalate, calcium and uric acid and lower phosphate than normal individuals. Citrate/calcium and magnesium/calcium ratio were significantly high in normal individuals than stone formers. Patients in group 2 excreted significantly higher urinary calcium and lower citrate that patients in group 1. Citrate/calcium ratio was higher in group 1 than group 2. Hypocitraturia, hyperoxaluria, hypercalciuria and increased citrate/calcium and magnesium/calcium ratio seem to be an essential risk factor for stone formation. Patients with recurrent stone formation could be distinguished from patients with first time stone formation on the basis of urinary calcium and citrate.  相似文献   
993.
Although the Internet is largely decentralized in its communication and social patterns, its technical and regulatory apparatuses are highly centralized and hierarchical. Consequently, digital communications are vulnerable to a degree of surveillance and censorship that would be unthinkable in traditional social arenas, threatening “Internet freedom” and cyberliberties in both democratic and politically repressed societies. We believe a new architecture is required in order to protect the continuance of civil liberties in networked society. In this article, we propose 10 “social specifications” describing the requirements of such a network, and outline an architecture called MondoNet that meets these specifications using ad hoc, wireless mesh networking technologies. We also address the legal and technical challenges facing the MondoNet project, and anticipate future developments in this field.  相似文献   
994.
995.
We examine engagement in commercial activities (consulting, patenting, and founding) among more than 2200 German and UK life scientists. We test hypotheses that include attributes of individuals, their material and social resources, and perceptions about values and reputation. We find that characteristics reflecting professional security, advantage and productivity are strong predictors for a greater breadth of participation in academic entrepreneurship, but not for all forms of technology transfer that we are able to test. For such academics, science and commerce go hand in hand, as they are best poised to straddle the boundary between industry and academy. We find strong support, however, that scientists perceive the value of patenting differently, and the level of reputational importance placed on scientific compared to commercial achievements matters in shaping commercial involvement.  相似文献   
996.
Heart failure (HF) is a frequent chronic disease in elderly people and represents a major health and economic burden. The accurate diagnosis of HF and the identification of high risk patients is mandatory to select the appropriate therapy and care. HF is associated to cardiac remodeling and inflammation and to the release of neurohormones. If natriuretic peptides remain the biomarkers of choice for the diagnosis and the prognosis of HF, several biomarkers related to cardiac remodeling and inflammation are available for testing and may add valuable information for the risk estimation of HF patients and for the selection of the most appropriated therapy. Furthermore, the quest for new efficient biomarkers of cardiac remodeling and inflammation is still ongoing and new candidates have been identified for a potential use in daily clinical practices. However, before their potential translation to routine parameters several challenges ranging form the analytical validation to the cost-effectiveness estimation should be considered.  相似文献   
997.
998.
After discussing the distinction between artifacts and natural entities, and the distinction between artifacts and technology, the conditions of the traditional account of moral agency are identified. While computer system behavior meets four of the five conditions, it does not and cannot meet a key condition. Computer systems do not have mental states, and even if they could be construed as having mental states, they do not have intendings to act, which arise from an agent’s freedom. On the other hand, computer systems have intentionality, and because of this, they should not be dismissed from the realm of morality in the same way that natural objects are dismissed. Natural objects behave from necessity; computer systems and other artifacts behave from necessity after they are created and deployed, but, unlike natural objects, they are intentionally created and deployed. Failure to recognize the intentionality of computer systems and their connection to human intentionality and action hides the moral character of computer systems. Computer systems are components in human moral action. When humans act with artifacts, their actions are constituted by the intentionality and efficacy of the artifact which, in turn, has been constituted by the intentionality and efficacy of the artifact designer. All three components – artifact designer, artifact, and artifact user – are at work when there is an action and all three should be the focus of moral evaluation.  相似文献   
999.
Salivary β-glucuronidase activity was studied in 20 healthy subjects without habits and 10 with habits, 38 untreated patients of advanced head and neck cancer and 21 patients after treatment either after surgery or radiation. Salivary β-glucuronidase activity was elevated in untreated cases of head and neck cancer (p<0.001), with a fall in the activity after treatment. The post operative fall in the activity of salivary β-glucuronidase activity was highly significant (p<0.001) as compared to post radiation. This test can be utilized in the diagnosis and also for monitoring the course of the disease.  相似文献   
1000.
Curcumin is a natural anti-inflammatory and antioxidant with several potential health benefits. Although it has been examined in several metals toxicity studies, but its role in the protection against copper toxicity has not been investigated. In this study; the detoxification and antioxidant effect of curcumin were examined to determine its prophylactic/therapeutic role experimentally in rats. Forty albino rats were divided into five groups; control, CuSO4 (4 mg/kg body weight), curcumin (80 mg/kg body weight), curcumin post-treatment (CuSO4 for 15 days followed by curcumin for the next 15 days) and curcumin co-treatment (CuSO4 plus curcumin for 30 days). All rats were treated orally by stomach tube for 30 days/once a day. Changes were observed in hepatic marker enzymes such as: aspartate aminotransferase (AST), alanine transaminase-(ALT), alkaline phosphatase (ALP) and gamma-glutamyltransferase (GGT), besides the serum total protein, urea and creatinine. Concentration of liver and kidney antioxidants such as: catalase (CAT), superoxide dismutase (SOD), reduced glutathione-(GSH) and malondialdehyde (MDA) were measured. An increased in the activities of liver marker enzymes, urea, creatinine and the MDA contents were detected after exposure to CuSO4. Meanwhile, the activities of serum total protein, hepatic and renal antioxidants were decreased. Changes in all biochemical parameters were alleviated by the post-treatment and co-treatment of curcumin. Our finding suggests that the curcumin showed protective effects on CuSO4-induced hepatotoxicity and nephrotoxicity.  相似文献   
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