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11.
The Benetton United Colors campaign illustrates how modern advertising has been radicalized into an explicitly political forum. Although lifestyle companies often attempt to associate their products with progressive social movements, Benetton was the first company to eliminate pictures of its products from its advertisements. In 1989, ads depicting Benetton's sportswear were replaced with powerful and problematic visual images of AIDS, environmental disasters, terrorism, and racism. Social issues became the embodiment of Benetton's product and, through the transformation into commodities, lost their significance as problematic human conditions. The campaign illustrates how the decontextualization of placing issues within the framework of product promotion, creates a tone of discordant meaning not adequately explained by mass culture critiques of consumerism. This case study recommends that advertising should be studied as a complex and contested social discourse within 1990s consumer culture.  相似文献   
12.
Dichlorvos applied weekly at the rate of 14.0 μg/l gave good control of Ephestia kuehniella in a flour mill. Other insects were also controlled. The insecticide was dispensed automatically by electrically operated sprayers when the mill was unoccupied. Exposure of test insects and chemical determinations of atmospheric concentrations showed that good distribution of vapour was obtained. Concentrations of dichlorvos were at a safe level for working well before the mill reopened after 8 hr. Contamination of flour was negligible. The method involves no disruption of routine working and there is no vapour hazard to workers.  相似文献   
13.
大面阵焦平面成像探测器需要具有随机开窗和反转读出功能,同时需要降低功耗。文章基于标准数字电路设计流程。设计了一种新型的基于格雷码编码规律的寻址计数器,用于对阵列的行地址和列地址进行寻址,提高了寻址的可靠性。对设计进行RTL级仿真,结果表明该设计能够实现任意开窗和反转读出功能。采用TSMC90工艺库对1024×1024阵列规模的RTL级设计进行分析计算,结果显示供电电压为3.3V时,寻址计数器功耗仅为19.56μW,整体设计功耗仅为58.75μW,适用于大面阵焦平面读出电路的设计。  相似文献   
14.
We have investigated the survival of Callosobruchus maculatus larvae when reared on resistant IT81D 1045 Vigna unguiculata seeds, whose resistance has been associated with variant forms of vicilins. Here, we present data which show that larvae of C. maculatus feeding on embryonic axis of resistant cowpea reach a mass of around 28 times higher than those feeding on cotyledonary tissues. Additionally, incorporation of 5–10% of embryonic axis flour on artificial seeds made of resistant flour restores toxicity of seeds to the bruchid. Vicilins purified from both susceptible and resistant embryonic axis had no deleterious effects either on insect development or on insect survival until a level of 4% of incorporation. In contrast, vicilins from resistant cotyledons show an LD50 (50% lethal dose) and WD50 (half weight dose) of 2%. Total vicilin contents of embryonic axes were around two times lower than in cotyledonary tissues, while proteolytic activities of all four proteinase classes were always higher in the former tissues. By 2D‐PAGE we visualized eight protein spots, which seem to be exclusively found on resistant cotyledons. Copyright © 2006 Society of Chemical Industry  相似文献   
15.
The pathway from the entorhinal cortical region to the hippocampal formation has previously been shown to be comprised of two sub-systems, one of which projects predominantly to the ipsilateral fascia dentata and regio inferior of the hippocampus proper, and a second which projects bilaterally to regio superior. The goal of the present investigation was to determine if these two pathways might originate from different cell populations within the entorhinal area. The cells of origin of these entorhinal pathways were identified by retrograde labeling with horseradish peroxidase (HRP). Injections which labeled the entorhinal terminal fields in both the fascia dentata and regio superior resulted in the retrograde labeling of two populations of cells in the entorhinal area. Ipsilateral to the injection, HRP reaction product was found in the cells of layer II (predominantly stellate cells) and the cells of layer III (predominantly pyramidal cells). Contralateral to the injections, however, the reaction product was found almost exclusively in the cells of layer III. With selective injections of the entorhinal terminal field in regio superior, only the cells of layer III were labeled, but these were labeled bilaterally. Selective injection of the entorhinal terminal field in the fascia dentata, however, resulted in the labeling of cells of layer II, but not of layer III, and these cells of layer II were labeled almost exclusively ipsilaterally. A very small number of labeled cells in layer II were, however, found contralateral to the injection as well. No labeled cells were found either in the presubiculum or parasubiculum following injections of the hippocampal formation. These cell populations were found capable of retrograde transport of HRP, however, since cells in both presubiculum and parasubiculum were labeled following HRP injections into the contralateral entorhinal area. These results suggest that the projections to the fascia dentata originate from the cells of layer II, while the projections to regio superior originate from the cells of layer III of the entorhinal region proper. The very slight crossed projection from the entorhinal area to the contralateral area dentata probably originates from the small population of cells in layer II which are labeled following HRP injections in the contralateral area dentata.  相似文献   
16.
Adrenergic receptors mediating depolarization in in vitro neonatal rat brown adipose tissue (BAT) have been characterized by use of adrenergic agonists and antagonists. Releasable endogenous catecholamine was present in BAT as demonstrated by tyramine- and 1,1-dimethyl-4-phenylpiperazinium iodide- (DMPP) induced depolarization in BAT from normal rats and its absence when BAT from reserpinized rats was used. In BAT from reserpinized rats l-norepinephrine, l-phenylephrine, and l-isoproterenol all similarly depolarized the bronw adipocytes over the concentration range of 10(-8) to 10(-6) M with a maximal depolarization of about 25 mV. Dopamine and d-norepinephrine were more than 100 times less potent. The beta-adrenergic blocker propranolol competitively inhibited isoproterenol-induced depolarization, whereas the alpha-adrenergic blackers, phentolamine and phenoxybenzamine, inhibited the phenylephrine-induced depolarization with much smaller inhibitory effects on the isoproterenol-induced depolarization. Both phenylephrine and isoproterenol elicited transient depolarizations when briefly added to the bathing medium while continuously recording from the same cell. Both the agonist and antagonist studies are interpreted as indicating the presence of both alpha- and beta-adrenergic receptors on BAT cells which mediate catecholamine-induced depolarization.  相似文献   
17.
112 patients with varicose small sephenous vein were operated upon. The operation was preceded by a careful clinical investigation, including phlebography. The observed changes were correlated with operative findings. It is shown that varicosity may be conditioned by an obstruction of blood outflow in the popliteal vein or small saphenous vein ostium. A relationship between some structural variants of the small saphenous vein and hemodynamic disturbances was noted.  相似文献   
18.
1 The mydriasis resulting from topical application of five atropine-like drugs was measured photographically in man. Drug potency was obtained from log dose-response curves. 2 The in vitro potency of eight cholinoceptor blocking drugs, including those studied in man, was obtained by measuring their affinity constants for binding to the receptors of an isolated preparation of the rabbit sphincter pupillae. Values agreed closely with those obtained for the muscarinic receptors of guinea-pig ileum. 3 In vitro and in vivo potency was compared to obtain a quantitative measure of the relative ease with which drugs gain access to the receptors after topical application. 4 The large differences that occur in the intensity and duration of the mydriatic response to atropine-like drugs is primarily the result of differences in their ability to blcok the receptors. Only with tropicamide does its relatively high accessibility affect its potency in man.  相似文献   
19.
Frame-by-frame analysis of angiograms in 16 patients revealed that hemodynamic interventions are capable of producing substantial shifts in the diastolic pressure-volume curve. Angiotensin raises blood pressure and shifts the entire pressure-volume curve up, and nitroprusside lowers blood pressure and shifts the curve down. Indirect measurements of pleural pressure in seven patients (via esophageal pressure) showed that pleural pressure changes were too small to account for these shifts. Analyzing our results in terms of a theoretical pressure-volume equation previously validated in dog studies did not show the observed shifts to be the product of acute changes in the elasticity of the myocardium itself. This same analysis suggested that indirect changes in the external mechanical constraints acting on the left ventricle such as the right ventricular pressure, the pericardium, and perhaps viscoelastic effects related to changes in filling rate account for the pressure-volume curve shifts with intervention. The fact that one cannot in general relate a specific volume to a given pressure in the face of hemodynamic interventions calls into question the use of end-diastolic pressure interchangeably with end-diastolic fiber length when interpreting systolic events in terms of the Frank-Starling mechanism.  相似文献   
20.
Rancinamycins are secondary metabolites produced by Streptomyces lincolnensis in a sulfur-depleted culture medium. The structures (except stereochemistry) of the main components of the rancinamycin-complex were determined by the use of IR, UV, PMR, and CMR spectra.  相似文献   
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