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11.
Marlene Davis Ekpo Jingxian Xie Yuying Hu Xiangjian Liu Fenglin Liu Jia Xiang Rui Zhao Bo Wang Songwen Tan 《International journal of molecular sciences》2022,23(5)
Antifreeze proteins (AFPs) or thermal hysteresis (TH) proteins are biomolecular gifts of nature to sustain life in extremely cold environments. This family of peptides, glycopeptides and proteins produced by diverse organisms including bacteria, yeast, insects and fish act by non-colligatively depressing the freezing temperature of the water below its melting point in a process termed thermal hysteresis which is then responsible for ice crystal equilibrium and inhibition of ice recrystallisation; the major cause of cell dehydration, membrane rupture and subsequent cryodamage. Scientists on the other hand have been exploring various substances as cryoprotectants. Some of the cryoprotectants in use include trehalose, dimethyl sulfoxide (DMSO), ethylene glycol (EG), sucrose, propylene glycol (PG) and glycerol but their extensive application is limited mostly by toxicity, thus fueling the quest for better cryoprotectants. Hence, extracting or synthesizing antifreeze protein and testing their cryoprotective activity has become a popular topic among researchers. Research concerning AFPs encompasses lots of effort ranging from understanding their sources and mechanism of action, extraction and purification/synthesis to structural elucidation with the aim of achieving better outcomes in cryopreservation. This review explores the potential clinical application of AFPs in the cryopreservation of different cells, tissues and organs. Here, we discuss novel approaches, identify research gaps and propose future research directions in the application of AFPs based on recent studies with the aim of achieving successful clinical and commercial use of AFPs in the future. 相似文献
12.
Univ.-Prof. DI Dr. Helmut Habersack DI Marlene Haimann Ass. Prof. Dr. Sándor Baranya Prof. Dr. János Józsa Mag. Angelika Riegler Dr Christine Sindelar DI Marcel Liedermann Johanna Ficsor Gabriella Mohácsiné Simon HR DI Dr. Michael Hengl 《?sterreichische Wasser- und Abfallwirtschaft》2014,66(9-10):340-347
The multiple uses of the Danube River for navigation, hydropower production and as a drinking water supply influence its ecological quality. Flow restrictions due to regulation as well as impacts on the sediment regime such as retention in the catchment area and interruption of the sediment continuum result in changes of the hydromorphological structures and can produce major problems in the context of sediment management. In light of these facts, cross-border investigations of sediment transport at the Danube River are called for. As there are no uniform research approaches shared by Austria and Hungary, the EU-funded project SEDDON (Sediment Research and Management at the Danube River) aims to compare different monitoring and modeling techniques used to determine sediment transport, and to develop mutual solutions. Further, the laboratory equipment currently used for hydraulic model experiments is evaluated and a research channel with a free flowing discharge of up to 10 m3/s without pumping will be constructed, allowing large-scale joint laboratory tests concerning sediment to be performed. 相似文献
13.
DI Marlene Haimann ao.Univ.-Prof. i. R. Dr. Otto Moog DI Dr. Ilse Stubauer Priv.-Doz. DI Dr. Michael Tritthart Univ.-Prof. DI Dr. Helmut Habersack 《?sterreichische Wasser- und Abfallwirtschaft》2014,66(9-10):316-326
In the case study “Winterhafen Linz” the effects of dredging/excavating fine sediments previously deposited by flood events and their subsequent dumping into the Danube mainstream were investigated. While this maintenance work was in progress, the temporal and spatial extent of the sediment plume and the changes in bed topography were measured. By employing air-lift samplers and grab samplers in the dredging and dumping areas, the question as to whether, and if so to what extent, the benthic invertebrate community was disturbed by the maintenance work. It could be clearly demonstrated that the sediment dredging severely affected the benthic invertebrates (an 82 % decline in biomass), while the dumping of the material had no effects on the Danube biota. Numerical modeling was used to simulate discharges and dumping locations other than those actually encountered during the monitoring campaign, thus making it possible to extrapolate and draw conclusions beyond the concrete results. These findings in turn provided the basis for recommendations on how to optimize dredging and dumping procedures on the Danube in future. 相似文献
14.
Friedman Michael A.; Schwartz Marlene B.; Brownell Kelly D. 《Canadian Metallurgical Quarterly》1998,66(4):646
Two measures of weight cycling and indexes of psychological functioning were examined in a large sample of dieters. History of weight cycling was assessed to include number of dieting attempts, total lifetime weight lost and regained, and number of weight cycles over 20 lb (9.1 kg). Experience of weight cycling measured perception of being a yo-yo dieter and perceived success at maintaining past weight losses. Experience was more strongly related than history to all psychological measures. Further, when controlling for the effects of age, body mass index, and experience, the relation between history and the psychological variables was nonsignificant. This finding suggests that an individual's perception of being a weight cycler may be more related to psychological problems than the actual number of pounds lost and regained over dine. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
15.
Developed a method for measuring goal heirarchies using an in-depth interview procedure with 25 male college seniors and 28 male blue-collar workers (aged 55–62 yrs). Ss were asked to describe (1) what they wanted out of life, (2) their daily activities, and (3) their goals in 6 domains of life: family, work and school, social life, leisure, personal growth, material, and other. A coding system was then used for constructing an Adult Intentional and Motivational Systems Chart for each Ss, using dimensions including life domain, level of generality, and means–end connections. Results indicate that people are aware of personal goals and satisfactions that guide their behavior. Evidence of validity and reliability suggest the continued use of the chart for research on self-direction and adult development as well as intervention efforts. Also, Ss who viewed their charts considered them to be accurate. (45 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
16.
Miguel Pinto Marlene Rebola Henriqueta Louro Alexandra M. M. Antunes Silvia S. José Maria Rocha 《Polycyclic Aromatic Compounds》2013,33(4):356-371
Polycyclic aromatic hydrocarbons (PAHs) are among the most persistent and toxic organic micropollutants present in water and several of them are mutagenic and carcinogenic. Although it has been shown that chlorinated derivatives of PAHs (Cl-PAHs) may be formed during the water chlorination procedure, little is known about their potential genotoxic and carcinogenic effects. The objectives of the present work were to prepare and characterize the major chlorinated derivatives of benzo[a]pyrene (BaP) and fluoranthene (Fluo), to develop an analytical methodology for their quantification in water samples and to analyse their potential genotoxicity. Chlorinated standards were prepared by a newly developed two phase method (water/n-hexane) using sodium hypochlorite. 6-Chloro-benzo[a]pyrene was selectively obtained from BaP, while 1,3-dichloro-fluoranthene and 3-chloro-fluoranthene were obtained from Fluo. All products were isolated and characterized by nuclear magnetic resonance and mass spectrometry. The formation of BaP- and Fluo-chlorinated derivatives under aqueous chlorination conditions was observed using a SPE-HPLC-FLD methodology. In addition, the cytotoxic and genotoxic activities of the three chlorinated derivatives were analyzed in comparison to their parent compounds, in a human-derived hepatoma cell line using the neutral red uptake and comet assays, respectively. The results showed that, at the equimolar doses of 100 and 125 μM, 6-Cl-BaP was able to induce a significantly higher level of DNA damage than BaP, suggesting a more potent genotoxic effect. In contrast, neither Fluo nor its chlorinated derivatives were genotoxic in the same cell line. The identification of new and possibly hazardous water chlorination by-product from PAHs emphasizes the need to minimize total organic carbon content of raw water and the implementation of safer water disinfection methods. 相似文献
17.
Compared the performance of 6 male patients (aged 24–65 yrs) with frontal lobe disease; 17 amnesic male patients (12 with etiology of alcoholic Korsakoff's disease [mean age 53.6 yrs] and 5 with surgically treated ruptured anterior communicating artery aneurysm [mean age 45.6 yrs]), and 12 male alcoholic controls (mean age 39.7 yrs) with no memory impairment on delayed alternation (DA) and delayed response (DR) tasks, known to be sensitive to frontal lobe damage in nonhuman primates. Ss (except the Korsakoff and alcoholic Ss) completed the Wechsler Memory Scale, and all Ss completed the Wechsler Adult Intelligence Scale (WAIS) and the Wisconsin Card Sorting Test. Results show that bilateral frontal lobe damage was associated with impairment on both tasks. There was no relation between performances on DA and DR and performance on the Wechsler Memory Scale, strengthening the suggestion that the former tasks are not sensitive to anterograde amnesia in humans. (41 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
18.
Philbeck John W.; Klatzky Roberta L.; Behrmann Marlene; Loomis Jack M.; Goodridge Jeremy 《Canadian Metallurgical Quarterly》2001,27(1):141
In some navigation tasks, participants are more accurate if they view the environment beforehand. To characterize the benefits associated with visual previews, 32 blindfolded participants were guided along simple paths and asked to walk unassisted to a specified destination (e.g., the origin). Paths were completed without vision, with or without a visual preview of the environment. Previews did not necessarily improve nonvisual navigation. When previewed landmarks stood near the origin or at off-path locations, they provided little benefit; by contrast, when they specified intermediate destinations (thereby increasing the degree of active control), performance was greatly enhanced. The results suggest that the benefit of a visual preview stems from the information it supplies for actively controlled locomotion. Accuracy in reaching the final destination, however, is strongly contingent upon the destination's location during the preview. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
19.
Rapid development of Internet technology has allowed a growing number of individuals and corporations to offer consumers, health care services, or "eHealth," including counseling and therapy. Almost no information exists about such individuals, due in part to difficulties in conducting research over the Internet. An Internet survey solicited backgrounds, communication technologies, and clinical interventions from individual behavioral eHealth care practitioners. Results are discussed regarding legal, ethical, and professional issues related to use of different Internet technologies. Psychologists are urged to give proper attention to empirical research, language, and current standards of practice before attempting to deliver counseling or psychotherapy over the Internet. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
20.
Examined whether monitoring failure or an illusion of knowing occurs when a reader's self-assessment of comprehension is high but an objective measure indicates comprehension failure. Unadulterated expository text was used. 48 undergraduates read either a difficult or an easy expository passage under instructions intended to elicit either deep processing or relatively shallow (but still semantic) processing. The illusion of knowing occurred primarily when the reading level of the passage was difficult and the instructions cued a relatively shallow level of processing. Ss who exhibited an illusion of knowing tended to have shown distortions in their passage summaries, whereas Ss who knew that they had failed to comprehend were more likely to have omitted information relevant to the main point. Findings provide a documentation of metacomprehension failure without the use of the contradiction paradigm. (16 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献