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61.
It is argued that “human-centredness” will be an important characteristic of systems that learn tasks from human users, as the difficulties in inductive inference rule out learning without human assistance. The aim of “programming by example” is to create systems that learn how to perform tasks from their human users by being shown examples of what is to be done. Just as the user creates a learning environment for the system, so the system provides a teaching opportunity for the user, and emphasis is placed as much on facilitating successful teaching as on incorporating techniques of machine learning. If systems can “learn” repetitive tasks, their users will have the power to decide for themselves which parts of their jobs should be automated, and teach the system how to do them — reducing their dependence on intermediaries such as system designers and programmers. This paper presents principles for programming by example derived from experience in creating four prototype learners: for technical drawing, text editing, office tasks, and robot assembly. A teaching metaphor (a) enables the user to demonstrate a task by performing it manually, (b) helps to explain the learner's limited capabilities in terms of a persona, and (c) allows users to attribute intentionality. Tasks are represented procedurally, and augmented with constraints. Suitable mechanisms for attention focusing are necessary in order to control inductive search. Hidden features of a task should be made explicit so that the learner need not embark on the huge search entailed by hypothesizing missing steps.  相似文献   
62.
It is an open question as to how impressions formed via computer-mediated communication (CMC) differ from those formed face-to-face (FtF). Some research suggests that judgments of others formed while interacting over CMC are more favorable than judgments formed in FtF, while other researchers argue the pattern is in the opposite direction. We sought to settle this conflict by examining impressions formed via each communication mode while controlling for the other. Participants interacted with a partner twice: once FtF and once CMC. When controlling for each communication mode, participants interacting FtF, formed more positive impressions of their partner than did those in the other sequence. Furthermore, FtF participants had greater self-other agreement then those who interacted via CMC. Implications for impressions formed over the Internet are discussed.  相似文献   
63.
Pecorino refers to Italian cheeses made exclusively from raw or pasteurized ewes' milk, characterized by a high content of fat matter and it is mainly produced in the Middle and South of Italy by traditional procedures. The autochthonous microbiota plays an important role in the organoleptic traits of Pecorino cheese and it can influence biogenic amines (BA) content.  相似文献   
64.
The COX-1 isoenzyme plays a significant role in a variety of diseases, as it catalyzes the bioprocesses behind many health problems. Among the diarylheterocycle class of COX inhibitors, the isoxazole ring has been widely used as a central heterocycle for the preparation of potent and selective COX-1 inhibitors such as P6 [3-(5-chlorofuran-2-yl)-5-methyl-4-phenylisoxazole]. The role of the isoxazole nucleus in COX-1 inhibitor selectivity has been clarified by preparing a set of new diarylheterocycles with various heterocycle cores. Replacement of isoxazole with isothiazole or pyrazole gave a drastic decrease in COX-1 inhibitory activity, whereas the introduction of an electron-donating group (EDG) on the N-aryl pyrazole allowed recovery of COX-1 inhibitory activity and selectivity. The EDG-equipped 5-(furan-2-yl)-1-(4-methoxyphenyl)-3-(trifluoromethyl)-1H-pyrazole (17) selectively inhibits COX-1 activity (IC(50) =3.4 μM; 28% COX-2 inhibition at 50 μM), in contrast to its inactive analogue, 3-(furan-2-yl)-1-phenyl-5-(trifluoromethyl)-1H-pyrazole, which does not bear the methoxy EDG. Molecular docking studies of compound 17 into the binding site of COX-1 shed light on its binding mode.  相似文献   
65.
This research compared technology use among homeless young adults with that of college students as a means of understanding technology use among young adults today; people who have grown up with technology. Specifically, social network site (SNS) usage was assessed for two age-matched young adult samples, one drawn from a large introductory psychology subject pool, and a second from homeless young adults who were approached for participation when they entered metropolitan shelters. Overall, technology use was strikingly similar. These results call for a paradigm shift in researchers’ understanding of technology use and indicate that contemporary young adults sampled across socio-economic class and varying ethnicities are far more similar than prior research would suggest. These results call into question whether the term “digital divide” is useful for describing group differences in technology use as our results suggest the divide has narrowed considerably.  相似文献   
66.
Fibromyalgia is a chronic condition characterized by persistent widespread pain that significantly reduces quality of life in patients. The purinergic P2X7 receptor (P2X7R) seems to be involved in different pain states and neuroinflammation. The purpose of this study is to investigate the positive effects of P2X7R inhibition by the antagonist Brilliant Blue G (BBG) in a rat model of reserpine-induced fibromyalgia. Sprague–Dawley male rats were injected with 1 mg/kg of reserpine for three consecutive days. Later, animals were administered BBG (50 mg/kg) intraperitoneally for seven days. Reserpine injections induced a significant increase in pain pro-inflammatory mediators as well as a significant increase in neuroinflammation. Chronic pain, in turn, led to depressive-like symptoms and reduced neurogenesis. Blockage of P2X7R by BBG administrations is able to attenuate the behavioral deficits, pain mediators and microglial activation induced by reserpine injection. Additionally, BBG prevents NLRP3 inflammasome activation and consequently the release of active interleukin (IL)-1 and IL-18, involved in the activation of nociceptors. In conclusion, these results suggest that inhibition of P2X7R should be further investigated to develop a potential approach for the management of fibromyalgia.  相似文献   
67.
68.
Benign ulceration of the cecum is an uncommon lesion that was originally described by Cruveilhier in 1832. Etiology is unknown and symptomatology not pathognomonic. Pre-operative and intraoperative diagnosis is rare and difficult. Definitive diagnosis is usually obtained by histologic evaluation of the surgical specimen after a right hemicolectomy performed for a suspect of a neoplasm of the cecum. The authors present 7 cases of cecal ulcers and suggest that preoperative diagnosis may be due after a colonoscopy with biopsy. This examination may be performed only in that cases that appear without symptoms of acute abdomen. The authors suggest also to perform right hemicolectomy.  相似文献   
69.
The biodegradation of propylene glycol (PG) and PG-based aircraft deicing fluid (ADF) at initial concentrations of 400–100,000?mg/L was investigated in saturated sand columns operated under nitrogen-limited conditions that are expected occur in the environment. PG biodegradation resulted in the accumulation of 0.4–1.4?mg volatile solids/g sand, which decreased the hydraulic conductivity of the sand by 23–99.8%. At loading up to 0.27?mg ADF or PG/g sand/d, greater than 99% PG removal and 88% soluble chemical oxygen demand (COD) removal were achieved. At higher loading, removal efficiency decreased but the removal rate increased to 11.2?mg?PG/g sand/day and up to 10.7?mg COD/g sand/day. As ADF or PG loading increased causing more nitrogen-limited conditions and likely a greater amount of PG fermentation, cell yields decreased and a greater fraction of incomplete mineralization of the ADF and PG were noted as measured by higher residual soluble COD. The results indicate that natural attenuation of PG in groundwater is likely to occur in association with potentially significant bioclogging.  相似文献   
70.
Hybrid composites obtained upon blending conjugated polymers and colloidal semiconductor nanocrystals are regarded as attractive photo­active materials for optoelectronic applications. Here it is demonstrated that tailoring nanocrystal surface chemistry permits to control non‐covalent and electronic interactions between organic and inorganic components. The pending moieties of organic ligands at the nanocrystal surface are shown to not merely confer colloidal stability while hindering charge separation and transport, but drastically impact morphology of hybrid composites during formation from blend solutions. The relevance of this approach to photovoltaic applications is demonstrated for composites based on poly(3‐hexylthiophene) and lead sulfide nanocrystals, considered as inadequate until this report, which enable the fabrication of hybrid solar cells displaying a power conversion efficiency that reaches 3%. By investigating (quasi)steady‐state and time‐resolved photo‐induced processes in the nanocomposites and their constituents, it is ascertained that electron transfer occurs at the hybrid interface yielding long‐lived separated charge carriers, whereas interfacial hole transfer appears hindered. Here a reliable alternative aiming to gain control over macroscopic optoelectronic properties of polymer/nanocrystal composites by mediating their non‐covalent interactions via ligands' pending moieties is provided, thus opening new possibilities towards efficient solution‐processed hybrid solar cells.  相似文献   
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