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901.
Anders Albrechtslund 《Ethics and Information Technology》2007,9(1):63-72
This article offers a discussion of the connection between technology and values and, specifically, I take a closer look at
ethically sound design. In order to bring the discussion into a concrete context, the theory of Value Sensitive Design (VSD)
will be the focus point. To illustrate my argument concerning design ethics, the discussion involves a case study of an augmented
window, designed by the VSD Research Lab, which has turned out to be a potentially surveillance-enabling technology. I call
attention to a “positivist problem” that has to do with the connection between the design context and the use context, which
VSD seems to presuppose, and I argue that it is necessary to clearly distinguish between the two, since the designers’ intentions
do not always correspond with the users’ practice; in fact, the relation between design and use is very complex and principally
unpredictable. Thus, a design theory must accept that foresight is limited to anticipation rather than prediction. To overcome
the positivist problem, I suggest a phenomenological approach to technology inspired by Don Ihde’s concept of multistability.
This argument, which is general in nature and thus applies to any theory of design ethics, is intended as a constructive criticism,
which can hopefully contribute to the further development of design ethics. 相似文献
902.
903.
904.
905.
In previous studies, we have reported first in vivo evidence of copper deposition in the choroid plexus, cognitive impairments, astrocytes swelling (Alzheimer type II cells) and astrogliosis (increase in number of astrocytes), and degenerated neurons coupled with significant increase in the hippocampus copper and zinc content in copper-intoxicated Wistar rats. Nonetheless, hippocampus iron levels were not affected by chronic copper-intoxication. Notwithstanding information on distribution of copper, zinc and iron status in different regions of brain due to chronic copper exposure remains fragmentary. In continuation with our previous study, the aim of this study was to investigate the effects of intraperitoneally injected copper lactate (0.15 mg Cu/100 g body weight) daily for 90 days on copper, zinc and iron levels in different regions of the brain using atomic absorption spectrophotometry. Copper-intoxicated group showed significantly increased cortex, cerebellum and striatum copper content (76, 46.8 and 80.7 % increase, respectively) compared to control group. However, non-significant changes were observed for the zinc and iron content in cortex, cerebellum and striatum due to chronic copper exposure. In conclusion, the current study demonstrates that chronic copper toxicity causes differential copper buildup in cortex, cerebellum and striatum region of central nervous system of male Wistar rats; signifying the critical requirement to discretely evaluate the effect of copper neurotoxicity in different brain regions, and ensuing neuropathological and cognitive dysfunctions. 相似文献
906.
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
907.
J. B. Varuna Kumara N. R. Ravikumara Basavaraj Madhusudhan 《Indian journal of clinical biochemistry : IJCB》2016,31(4):390-401
Folic acid is used for preventing and treating multiple diseases and disorders, administered in the form of oral supplements. The present research work was aimed to study the influence of two non-ionic surfactants Poloxamer and Tween 80 (Polysorbate 80) on pectin submicrospheres formulations. Typical natural polymer pectin was used to encapsulate folic acid by cross linking method. The resultant submicrospheres contributed to improve the aqueous solubility to enhance the bioavailability of folic acid. During investigation, it was observed that pectin polymers influenced kinetics of the rate of reaction more intensively than the surfactants. The physical phenomenon caused the change in their size, shape and chemistry of pectin polymers transforming into submicrospheres in aqueous condition. The characteristic differences of submicrospheres were assessed by scanning electron microscopy, differential scanning calorimetry and Fourier-transform infrared spectroscopy. The average diameters of the submicrospheres ranged between 250 and 500 nm. The encapsulation efficiency of submicrospheres ranged between 80 and 96 %. The characteristic swelling behavior of lyophilized submicrospheres was influenced by the ratio of pectin polymers and folic acid used in the formulations. The submicrospheres systems exhibited controlled release of folic acid due to the pH-dependent solubility of pectin polymers in aqueous medium. The submicrospheres showed good haemocompatibility suggesting them to be promising candidates for oral delivery. 相似文献
908.
R. Kumar S. B. Pachori G. K. Senger Satyanand L. D. Joshi 《Indian journal of clinical biochemistry : IJCB》1994,9(2):72-74
Aim of present study was to compare the adenosine deaminase (ADA) activity in various types of arthritis conditions with synovial
effusion. No. significant difference was observed in ADA activity in serum of control and study groups but results have shown
a definite pattern of ADA activity in synovial fluid in various arthritic conditions. The highest value of ADA activity was
observed in synovial fluid of patients with tubercular arthritis followed by rheumatoid, septic, osteo and post traumatic
arthritis. Thus measurement of ADA activity in synovial fluid can be used as a parameter of differential diagnosis of arthritis
specially tubercular in initial stages. 相似文献
909.
Serum total cholesterol and triglyceride levels were estimated in 45 dilated cardiomyopathy (DCM) patients and were compared
with 31 healthy controls. The total serum cholesterol (215±50 mg/dl) and serum triglyceride (162±76 mg/dl) levels in DCM patients
did not show any significant changes as compared to normal controls. The cholesterol and triglyceride and the individual lipoprotein
fractions, viz HDL, VLDL, LDL and chylomicrons were analysed in 10 patients. The values did not differ significantly when
compared to those of controls. These findings suggest that serum lipids may not play a role in the antietiopathogenesis of
DCM. 相似文献
910.