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201.
What distinguishes scenes from nonscenes? Photographs of objects on both naturalistic and blank backgrounds yielded boundary extension (BE: memory for unseen spatial expanse outside the picture's boundaries). However, line-drawn objects on blank backgrounds did not (Experiment 1). Perhaps the blank background was construed as depicting a real-world surface in the photograph condition but was construed as depicting nothing in the line-drawn condition. To change background construal, the authors used objects cut out of photographs; these were placed on blank backgrounds while viewers watched (Experiments 2 and 3). BE was eliminated. The authors propose that amodal continuation is a fundamental aspect of scene perception. However, not all pictures are scenes--only pictures construed as depicting a truncated view of a continuous world, (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
202.
Motile metal?organic frameworks (MOFs) are potential candidates to serve as small‐scale robotic platforms for applications in environmental remediation, targeted drug delivery, or nanosurgery. Here, magnetic helical microstructures coated with a kind of zinc‐based MOF, zeolitic imidazole framework‐8 (ZIF‐8), with biocompatibility characteristics and pH‐responsive features, are successfully fabricated. Moreover, it is shown that this highly integrated multifunctional device can swim along predesigned tracks under the control of weak rotational magnetic fields. The proposed systems can achieve single‐cell targeting in a cell culture media and a controlled delivery of cargo payloads inside a complex microfluidic channel network. This new approach toward the fabrication of integrated multifunctional systems will open new avenues in soft microrobotics beyond current applications.  相似文献   
203.
The Cananéia estuary is an important biological area on the southeast coast of Brazil. In the past, it was impacted by both chlorinated pesticides and polychlorinated biphenyls (PCBs) due to its natural location. The marine tucuxi dolphin (Sotalia fluviatilis) is a top predator in this ecosystem and can be found year round in Cananéia estuarine waters that represent an important nursing area for the species. This work investigated chlorinated compounds in the blubber of nine individuals from the Cananéia estuary. Residue levels of DDTs (0.541-125 microg g(-1) lipid wt.) were the highest, followed by PCBs (0.2-9.22 microg g(-1) lipid wt.), mirex (0.014-0.312 microg g(-1) lipid wt.), chlordanes (0.001-0.047 microg g(-1) lipid wt.), HCHs (<0.003-0.044 microg g(-1) lipid wt.), and HCB (n.d.-0.024 microg g(-1) lipid wt.). The mean p,p'-DDE/Sigma DDT ratio was approximately 0.8 and is indicative of the former DDT application in the study area. PCB contamination is suggested to be associated with atmospheric transport and relative proximity to the Cubat?o industrial complex-the most important along the Brazilian coast. Low levels of HCHs and HCB can be attributed to their high volatility in tropical environments. Concentrations of organochlorines in the blubber of marine tucuxis from the Cananéia estuary were lower than levels found in small cetacean species from developed countries, where the input of these compounds was considerably greater than in Brazil. At extremes, male dolphins can present DDT burden several orders of magnitude higher than females. Despite the high levels of total DDT found in males, the major detected compound was p,p'-DDE which is considered to be of low toxicity.  相似文献   
204.
In 2001, samples of liver (n = 38) and perirenal fat (n = 25) (only in males) were taken from European roe deer (Capreolus capreolus) populating a hilly, wooded protected area in the Emilia-Romagna region of Northern Italy. Samples were analyzed for organochlorine pesticides dichlorodiphenyltrichloroethane (DDT) and its metabolites, hexachlorobenzene (HCB), hexachlorocycloexane alpha-, beta- and gamma-isomers (alpha-, beta- and gamma-HCH), alpha-endosulfan, aldrin, dieldrin and endrin, and the seven PCB 'indicator' congeners IUPAC Nos. 28, 52, 101, 118, 138, 153 and 180, in order to investigate the current state of contamination of the area and to assess the possible toxicological risks for the monitored species. p,p'-DDE was detected in 95% of the liver and perirenal fat samples (n = 63), at concentrations ranging from < dl to 629.3 ng/g lipid weight, which were much higher than those found for HCB and gamma-HCH. The concentrations of the other measured organochlorine pesticides and metabolites were below the detection limit in all the samples. PCBs were found in 97% of the liver and perirenal fat samples, at total levels ranging between < dl to 414.5 ng/g lipid weight. The hepta- and hexa-chlorinated congeners 180, 153 and 138 were predominant and comprised more than 70% of the total seven PCBs in both the liver and perirenal fat samples. In the male roe deer, significantly higher concentrations of HCB, p,p'-DDE and PCBs were found in the liver than in the perirenal fat (P < 0.001). Hepatic levels of p,p'-DDE and PCBs were significantly higher in males than in females (P < 0.05 and P < 0.001, respectively). No significant differences in organochlorine concentrations were observed between juvenile and adult males in either tissue sample (P > 0.05). Females were not statistically tested because they were all adults. The levels of organochlorine contaminants were well below those associated with adverse reproductive effects and lethality in mammals.  相似文献   
205.
Vascular calcification (VC) is a risk factor for cardiovascular events and mortality in chronic kidney disease (CKD). Several components influence the occurrence of VC, among which inflammation. A novel uremic toxin, lanthionine, was shown to increase intracellular calcium in endothelial cells and may have a role in VC. A group of CKD patients was selected and divided into patients with a glomerular filtration rate (GFR) of <45 mL/min/1.73 m2 and ≥45 mL/min/1.73 m2. Total Calcium Score (TCS), based on the Agatston score, was assessed as circulating lanthionine and a panel of different cytokines. A hemodialysis patient group was also considered. Lanthionine was elevated in CKD patients, and levels increased significantly in hemodialysis patients with respect to the two CKD groups; in addition, lanthionine increased along with the increase in TCS, starting from one up to three. Interleukin IL-6, IL-8, and Eotaxin were significantly increased in patients with GFR < 45 mL/min/1.73 m2 with respect to those with GFR ≥ 45 mL/min/1.73 m2. IL-1b, IL-7, IL-8, IL-12, Eotaxin, and VEGF increased in calcified patients with respect to the non-calcified. IL-8 and Eotaxin were elevated both in the low GFR group and in the calcified group. We propose that lanthionine, but also IL-8 and Eotaxin, in particular, are a key feature of VC of CKD, with possible marker significance.  相似文献   
206.
Mozzarella di Bufala Campana is a pasta filata cheese with a Protected Designation of Origin whose specifications require the use of fresh milk, forbidding the use of frozen curds. The goal is to develop a routine analysis to identify frozen curd presence. The Buffalo Mozzarella samples were analysed by the near-infrared analytical technique, and the spectral data were processed through an artificial neural network. The results make it possible to identify the use of frozen curd in samples of Buffalo Mozzarella for up to 9 days of storage. The model reported very high accuracy either in training (0.5% of bad prediction) or in tests (6.8% of bad prediction).  相似文献   
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