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71.
The effectiveness of the pink-juice test to determine 79.4 °C end-point temperature (EPT) of cooked beef logs was appraised. Logs made from five cuts of meat from three animal age groups were fabricated in triplicate to simulate products received at ports of entry and then cooked to EPTs of 78.0–81.8 °C. CIELAB L*, a*, b*, C and h ° values of internal surfaces of freshly sliced meat and pressed juices from samples were determined. Sensory ratings were made by six trained panelists to determine intensities of residual red color of the juices. Animal age and cut of meat had little effect on the CIELAB color values. Residual red color was apparent in all samples by both sensory and a* values analysis. Sensory ratings did not vary significantly (P < 0.05) by animal age or cut of meat. Average values of 3.2 (intensity range, 1–9) corresponded to an EPT slightly greater than 80 °C; absence of red color in the juices would therefore indicate an EPT in excess of the target temp of 79.4 °C. Residual glutamic-oxaloacetic transaminase activity (GOT) activity, used as a collateral test for EPT, ranged from 482.5 to 1641.8 SFU ml−1 of juice and differed significantly by cut of meat (P < 0.05), but not by animal age. © 1999 Society of Chemical Industry  相似文献   
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Studied the effects of 3 task-solving strategies on group efficiency and effectiveness by having 60 U.S. Army soldiers work in dyads either under a shared labor strategy or 1 of 2 divided labor strategies. Tasks included a difficult and an easy crossword puzzle. On the average, dividing labor resulted in greater efficiency (amount of work per man hour). Requiring Ss to work together resulted in substantially greater group effectiveness (total performance), but this effect occurred primarily on the easy task. It is suggested that a high degree of member interdependence maximizes redundancy of task-relevant abilities, resulting in generally superior performance effectiveness but frequently at the cost of efficiency. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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Hypothesized that (a) persons high in self-esteem make 2nd vocational choices that are consistent with their personality styles more often than those that are inconsistent, and (b) persons low in self-esteem make 2nd choices that are consistent about as often as they make choices that are inconsistent. In a test with 135 undergraduates using the Vocational Preference Inventory, both hypotheses were supported. Implications were drawn for counseling with persons whose preferred career choices were inappropriate. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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Density functional methods were used to predict the antioxidative efficiency of thirteen 4-benzylidenamino-4, 5-dihydro-1H-1,2,4-triazol-5-one derivatives in the gas phase and in the solution phase (water and benzene). Optimized geometries of molecules and reaction thermodynamic energies (enthalpies and reaction-free energies) of three main antioxidant mechanisms (hydrogen atom transfer, single electron transfer-proton transfer, and sequential proton loss electron transfer) were studied at B3LYP/6-31G (d,p) level. Solvent contributions to thermodynamic energies were computed employing integral equation formalism integral equation formalism polarized continuum model method. Obtained results revealed that the three main working mechanisms were endothermic, but not spontaneous especially in the gas phase. We found that the single electron transfer process from the anionic form was more preferable than that from the neutral form in the gas phase. The comparison of the ionization potentials of 4-benzylidenamino-4, 5-dihydro-1H-1,2,4-triazol-5-one derivatives to those of classical antioxidants (gallic acid, caffeic acid, ferulic acid, and ascorbic acid) indicated that the electron transfer mechanism was more predominant in the thirteen 4-benzylidenamino-4, 5-dihydro-1H-1,2,4-triazol-5-one derivative compounds. Thermodynamically, single electron transfer process from the anionic form was the most preferable mechanism in the gas phase. Solvent effect drastically modified thermodynamic energies of mechanisms. The proton transfer process was the thermodynamically favored mechanism as compared to other mechanisms in both solvents. It is worth mentioning that all the mechanisms were found not to be spontaneous in the solution phase except the proton transfer process.  相似文献   
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There is an urgent need to better understand the mechanisms involved in scar formation in the brain. It is well known that astrocytes are critically engaged in this process. Here, we analyze incipient scar formation one week after a discrete ischemic insult to the cerebral cortex. We show that the infarct border zone is characterized by pronounced changes in the organization and subcellular localization of the major astrocytic protein AQP4. Specifically, there is a loss of AQP4 from astrocytic endfoot membranes that anchor astrocytes to pericapillary basal laminae and a disassembly of the supramolecular AQP4 complexes that normally abound in these membranes. This disassembly may be mechanistically coupled to a downregulation of the newly discovered AQP4 isoform AQP4ex. AQP4 has adhesive properties and is assumed to facilitate astrocyte mobility by permitting rapid volume changes at the leading edges of migrating astrocytes. Thus, the present findings provide new insight in the molecular basis of incipient scar formation.  相似文献   
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Darwin  S.  Arun Samuel  T. S. 《SILICON》2020,12(2):393-403
Silicon - The 2D analytical models for electrostatic potential, threshold voltage, subthreshold swing, Drain Induced Barrier Lowering (DIBL) and drain current of the Dual Material Double Gate...  相似文献   
80.
The nasal epithelium is a key portal for infection by respiratory viruses such as SARS-CoV-2 and represents an important target for prophylactic and therapeutic interventions. In the present study, we test the safety and efficacy of a newly developed nasal spray (AM-301, marketed as Bentrio) against infection by SARS-CoV-2 and its Delta variant on an in vitro 3D-model of the primary human nasal airway epithelium. Safety was assessed in assays for tight junction integrity, cytotoxicity and cilia beating frequency. Efficacy against SARS-CoV-2 infection was evaluated in pre-viral load and post-viral load application on airway epithelium. No toxic effects of AM-301 on the nasal epithelium were found. Prophylactic treatment with AM-301 significantly reduced viral titer vs. controls over 4 days, reaching a maximum reduction of 99% in case of infection from the wild-type SARS-CoV-2 variant and more than 83% in case of the Delta variant. When AM-301 administration was started 24 h after infection, viral titer was reduced by about 12-folds and 3-folds on Day 4. The results suggest that AM-301 is safe and significantly decelerates SARS-CoV-2 replication in cell culture inhibition assays of prophylaxis (pre-viral load application) and mitigation (post-viral load application). Its physical (non-pharmaceutical) mechanism of action, safety and efficacy warrant additional investigations both in vitro and in vivo for safety and efficacy against a broad spectrum of airborne viruses and allergens.  相似文献   
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