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排序方式: 共有449条查询结果,搜索用时 15 毫秒
91.
Advances in the Structural Strategies of the Self-Assembly of Photoresponsive Supramolecular Systems
Vivian J. Santamaria-Garcia Domingo R. Flores-Hernandez Flavio F. Contreras-Torres Rodrigo Cu-Sampedro Jos Antonio Snchez-Fernndez 《International journal of molecular sciences》2022,23(14)
Photosensitive supramolecular systems have garnered attention due to their potential to catalyze highly specific tasks through structural changes triggered by a light stimulus. The tunability of their chemical structure and charge transfer properties provides opportunities for designing and developing smart materials for multidisciplinary applications. This review focuses on the approaches reported in the literature for tailoring properties of the photosensitive supramolecular systems, including MOFs, MOPs, and HOFs. We discuss relevant aspects regarding their chemical structure, action mechanisms, design principles, applications, and future perspectives. 相似文献
92.
Julius Pollinger Simone Schierle Sebastian Neumann Julia Ohrndorf Astrid Kaiser Dr. Daniel Merk 《ChemMedChem》2019,14(14):1343-1348
Automated computational analogue design and scoring can speed up hit-to-lead optimization and appears particularly promising in selective optimization of side-activities (SOSA) where possible analogue diversity is confined. Probing this concept, we employed the cysteinyl leukotriene receptor 1 (CysLT1R) antagonist cinalukast as lead for which we discovered peroxisome proliferator-activated receptor α (PPARα) modulatory activity. We automatically generated a virtual library of close analogues and classified these roughly 8000 compounds for PPARα agonism and CysLT1R antagonism using automated affinity scoring and machine learning. A computationally preferred analogue for SOSA was synthesized, and in vitro characterization indeed revealed a marked activity shift toward enhanced PPARα activation and diminished CysLT1R antagonism. Thereby, this prospective application study highlights the potential of automating SOSA. 相似文献
93.
The work in this article deals with enhancing the performance of rice straw (RS) for production of carbon nanostructures (CNSs), as aqueous phase adsorbents, as well as benefit solution for disposing of this undesirable waste and for avoiding the environmental risk from burning. In this respect, controlling the constituents of RS by enzymatic treatment, followed by hydrothermal treatment and carbonization was carried out. The benefit role of the performed treatments was supported via comparing these CNSs with those obtained from RS pretreated by chemical pulping processes; moreover, literature reported CNSs. Results deduced from SEM and TEM analyses showing that, the two investigated CNSs samples have different surface morphologies and comprised of graphitic carbons as nodules and multi-layer graphene sheets. The investigated RS-based CNSs own numerous of oxygen-containing functional groups with low specific surface area and high mesopore volume; thus, they exhibited high iodine number of 959 and 863 mg/g, respectively. The CNSs from hydrochar of peroxidase treated RS has higher uptake to methylene blue (MB) dye (358 mg/g) than that produced from hydrochar of cellulase treated RS (202 mg/g), this may be related to its unique nanostructure. Both values are higher than that of reported CNSs, which obtained from chemical pulping processes (~ 54–119 mg/g). The adsorption of MB dye is well-fitted with Langmuir and described by pseudo-second order kinetic model. 相似文献
94.
C M Vivian 《The Science of the total environment》1986,53(1-2):5-40
A review of the available and potential tracers of the movement and distribution of sewage sludge ('sludge') in and on marine sediments is presented. A brief review of 'active' sludge tracers is followed by a more extensive review of 'passive' sludge tracers. These can be broken down into five categories: Natural organic components of sludge--organic carbon, faecal steroids, carbohydrate/TOC ratio, tomato seeds. Synthetic organic compounds--silicones, chlorinated hydrocarbons, non-ionic surfactants and their degradation products, linear alkylbenzenes. Stable isotopes of carbon, nitrogen, hydrogen and sulphur. Inorganic substances and their properties--minerals, paint pigments, trace elements, magnetic properties. Biological/Microbiological--faecal bacteria, Clostridium welchii spores, amoebae, viruses, nitrogen-fixing enterobacteriaceae. A wide variety of sludge tracers are available with the choice of suitable tracers in an individual situation governed by the available equipment and expertise, cost considerations, ease of sampling requirements and determination, and the nature of other pollutant inputs in the vicinity of the input of interest. Ideally, the sludge tracers chosen should be unique to the input of interest, but this will rarely be achievable in practice. In areas of gross sludge contamination, a marine geophysical survey technique can be used to delineate the area affected and this provides a rapid cost-effective method for large areas. 相似文献
95.
JA Vivian S Kishioka ER Butelman J Broadbear KO Lee JH Woods 《Canadian Metallurgical Quarterly》1998,286(2):697-703
This study characterized the antinociceptive, respiratory and heart rate effects of the cannabinoid receptor agonists Delta-9-tetrahydrocannabinol (Delta-9-THC) and WIN 55212 ((R)-(+)-2, 3-dihydro-5-methyl-3-[(4-morpholinyl)methyl]pyrol-[1,2,3-de]-1, 4-benzoxazin-6-yl)(1-naphtalenyl)methanone monomethanesulfonate), N-arachidonyl ethanolamide (anandamide) and the mu and kappa opioid receptor agonists heroin and U69593, alone and in conjunction with a cannabinoid receptor antagonist, SR 141716A [N-(piperidin-1-1-yl)-5-(4-chlorophenyl)-1(2, 4-dichlorophenyl)-4-methyl-1H-pyrazole-3-carboxamide hydrochloride] and an opioid receptor antagonist, quadazocine, in rhesus monkeys (Macaca mulatta). Using 12 adult rhesus monkeys, latencies to remove the tail from a 50 degrees C water bath, respiration in 5% CO2 and heart rate were measured. When administered alone, SR 141716A (1.8, 5.6 mg/kg i.m.) did not alter nociception, respiration or heart rate. Delta-9-THC (0.1-10 mg/kg i.m.) and WIN 55212 (0.1-10 mg/kg i.m.) dose-dependently increased antinociception and dose-dependently decreased respiratory minute and tidal volumes and heart rate. These antinociceptive, respiratory and heart rate effects were reversed by SR 141716A but not by the opioid antagonist quadazocine (1 mg/kg i.m.). Anandamide (10 mg/kg i.m.) also produced antinociception. Heroin (0.01-10 mg/kg i.m.) and U69593 (0.01-3.2 mg/kg i.m.) also dose-dependently increased antinociception and decreased respiratory and heart rate measures; these effects were antagonized by quadazocine but not by SR 141716A. These results demonstrate selective and reversible antagonism of cannabinoid behavioral effects by SR 141716A in rhesus monkeys. 相似文献
96.
97.
Szapocznik José; Rio Arturo; Murray Edward; Cohen Raquel; Scopetta Mercedes; Rivas-Vazquez Ana; Hervis Olga; Posada Vivian; Kurtines William 《Canadian Metallurgical Quarterly》1989,57(5):571
Structural family therapy, psychodynamic child therapy, and a recreational control condition were compared for 69 six-to-twelve-year-old Hispanic boys who presented with behavioral and emotional problems. The results suggest that the control condition was significantly less effective in retaining cases than the two treatment conditions, which were apparently equivalent in reducing behavioral and emotional problems as well as in improving psychodynamic ratings of child functioning. Structural family therapy was more effective than psychodynamic child therapy in protecting the integrity of the family at 1-year follow-up. Finally, the results did not support basic assumptions of structural family systems therapy regarding the mechanisms mediating symptom reduction. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
98.
N. Merk 《Journal of Materials Science Letters》1995,14(8):592-595
99.
Adelman Howard S.; Lusk Robert; Alvarez Vivian; Acosta N. Katherine 《Canadian Metallurgical Quarterly》1985,16(3):426
Examined the ability of 43 10–19 yr olds with learning and behavior problems to evaluate and perform in interventions related to their problems under conditions of presumed or explicit consent. Ss performed mathematics problems of varying degrees of difficulty and indicated their affective response to the task, reactions to performance demands, and performance attributions. Despite low academic skills and some deviant behavior, the majority of Ss demonstrated a relatively high level of ability to understand, evaluate, communicate, and perform, as measured by the accuracy of self-estimates of skill, self-explanations of behavior, and on-task functioning. Inaccurate skill estimates and negative reactions to the task were more frequent when consent was presumed rather than explicitly sought. Data suggest that many minors have the competence necessary for effectively participating in treatment decision making. (31 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
100.
L Büdinger L Borradori C Yee R Eming S Ferencik H Grosse-Wilde HF Merk K Yancey M Hertl 《Canadian Metallurgical Quarterly》1998,102(12):2082-2089
Antibodies against the extracellular domain of bullous pemphigoid antigen 2 (BPAG2) are thought to play a key role in the pathogenesis of bullous pemphigoid (BP), the most frequent autoimmune bullous disease of the skin. Autoreactive T cell responses to BPAG2 were investigated in 16 BP patients and 24 healthy controls by coculture of PBMC with two recombinant BPAG2 proteins (extracellular domain of BPAG2). Primary in vitro T cell responses to BPAG2 were observed in 10/12 BP patients expressing the BP-associated HLA-DQB1*0301 allele and 8/10 DQB1*0301 positive healthy individuals. DQB1*0301 also restricted three autoreactive T cell lines from two BP patients and a healthy donor. In contrast, PBMC from 14 normal patients carrying HLA class II alleles other than DQB1*0301 were not stimulated by BPAG2. Autoreactive BPAG2-specific CD4(+) T cell lines and clones from five BP patients produced both Th1 and Th2 cytokines, whereas three autoreactive T cell lines from three DQB1*0301 positive normal patients produced exclusively IFN-gamma. The absence of BPAG2-specific Th2 cells in healthy individuals strongly suggests that autoreactive Th2 responses to BPAG2 are restricted to BP patients and may thus be critical in the pathogenesis of BP. 相似文献