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71.
We connected dislocation-based atomic-scale and continuum models of plasticity in crystalline solids through numerical simulations of dislocation intersections in face-centered cubic crystals. The results contradict the traditional assumption that strain hardening is governed by the formation of sessile junctions between dislocations. The interaction between two dislocations with collinear Burgers vectors gliding in intersecting slip planes was found to be by far the strongest of all reactions. Its properties were investigated and discussed using a multiscale approach. 相似文献
72.
Micrometer-sized bubbles are unstable and therefore difficult to make and store for substantial lengths of time. Short-term stabilization is achieved by the addition of amphiphilic molecules, which reduce the driving force for dissolution. When these molecules crystallize on the air/liquid interface, the lifetime of individual bubbles may extend over a few months. We demonstrated low gas-fraction dispersions with mean bubble radii of less than 1 micrometer and stability lasting more than a year. An insoluble, self-assembled surfactant layer covers the surface of the microbubbles, which can result in nanometer-scale hexagonal patterning that we explain with thermodynamic and molecular models. The elastic response of the interface arrests the shrinkage of the bubbles. Our study identifies a route to fabricate highly stable dispersions of microbubbles. 相似文献
73.
Atmospheric deposition at Rothamsted,Saxmundham, and Woburn experimental stations,England, 1969–1984
Keith W. T. Goulding Paul R. Poulton Victor H. Thomas Rodney J. B. Williams 《Water, air, and soil pollution》1986,29(1):27-49
The pH of precipitation, and the concentrations in precipitation and depositions by precipitation of H+, major cations, N, S, and chloride were measured in bulk collectors at three sites in Eastern England. The Rothamsted site is 100 km from the coast in a semi-urban environment. The Saxmundham site is 13 km and the Woburn site 120 km from the coast; both are in rural environments. Precipitation is acidic at all three sites, with a pH of 4.3 at Rothamsted and 5.0 at Saxmundham and Woburn at present, but the pH has been increasing. Precipitation chemistry is chiefly controlled by sea-salts (Na, Mg, Cl) and earth salts (K, Ca, Mg, NH4, N03). Sea-salts dominate near the coast at Saxmundham, but earth salts become much more important inland at Rothamsted and at Woburn. The concentration and deposition of non-sea Cl are increasing at Rothamsted and Saxmundham, those of non-sea SO4-S are increasing at Woburn, and those of NO3-N are increasing at all of the sites. Precipitation acidity is associated chiefly with non-sea SO4, and only a little with NO3 and non-sea Cl, at Rothamsted and Woburn. At Saxmundham, no correlation between acidity and anions is observed, presumably because of the overwhelming effect of sea-salts. 相似文献
74.
This composition collects the discussion conclusions of each group during the seminar.Each group discussion has a topic,and each group sends an expert giving a speech in the summary meeting to report the outcome of the discussion.All of the outcomes put forward the direction and methods in the development of industrialised housing in Chongqing,and also set up a basis for the work of the next stage of this project. 相似文献
75.
Liliana Endo‐Munoz Tristram C. Bennett Eleni Topkas Sherry Y. Wu Douglas H. Thamm Laura Brockley Maureen Cooper Scott Sommerville Maurine Thomson Kathleen O'Connell Amy Lane Guy Bird Anne Peaston Nicholas Matigian Rodney C. Straw Nicholas A. Saunders 《Veterinary and comparative oncology》2020,18(2):206-213
Osteosarcoma is the most common paediatric primary bone malignancy. The major cause of death in osteosarcoma is drug‐resistant pulmonary metastasis. Previous studies have shown that thioredoxin reductase 2 is a driver of metastasis in osteosarcoma and can be inhibited by auranofin (AF). Moreover, studies have shown that AF significantly reduces pulmonary metastases in xenotransplant models. Here, we describe a phase I/II study of AF in canine osteosarcoma, a well‐recognized spontaneous model of human osteosarcoma. We performed a single‐arm multicentre pilot study of AF in combination with standard of care (SOC) (amputation + carboplatin). We recruited 40 dogs to the trial and used a historical SOC‐only control group (n = 26). Dogs >15 kg received 9 mg AF q3d PO and dogs <15 kg received 6 mg q3d. Follow‐up occurred over at least a 3‐year period. Auranofin plus SOC improved overall survival (OS) (P = .036) in all dogs treated. The improved outcome was attributable entirely to improved OS in male dogs (P = .009). At the time of writing, 10 dogs (25%) survive without measurable disease in the treatment group with survival times ranging between 806 and 1525 days. Our study shows that AF improves OS in male dogs when combined with SOC. Our findings have translational relevance for the management of canine and human osteosarcoma. Our data justify a larger multicentre phase 2 trial in dogs and a phase I/II trial in human patients with refractory disease at the time of initial surgery. 相似文献
76.
de Souza Romina Peña-Fleitas M. Teresa Thompson Rodney B. Gallardo Marisa Grasso Rafael Padilla Francisco M. 《Precision Agriculture》2022,23(1):278-299
Precision Agriculture - To increase nitrogen (N) use efficiency and reduce water pollution from vegetable production, it is necessary to optimize N management. Fluorescence-based optical sensors... 相似文献
77.
Leone L. Mohney Donald V. Lightner Rodney R. Williams Michael Bauerlein 《Journal of the World Aquaculture Society》1990,21(3):186-191
Nauplii of the brine shrimp, Artemia , and cultures of the soil nematode, Panagrellus redivivus , were fed a suspension of the water-insoluble antibacterial Romet-30 (sulfadimethoxine plus ormetoprim) to determine if they could be used as a mechanism for delivery of the drug to larval penaeid shrimp.
Romet-30 was added to groups of brine shrimp nauplii and nematodes in 1 L beakers to achieve a concentration of 3 mg of drug per ml of seawater. After a 4 h uptake period, predetermined numbers of organisms were assayed for antibiotic content using the micro-plate diffusion method and a Romet-30 sensitive strain of Vibrio alginolyticus as the indicator. The resulting zones of inhibition were compared to that of a standard Kirby-Bauer sensitivity disc containing 25 μg of the drug that was placed on each plate as standard control. Negative controls consisted of equal numbers of nauplii and nematodes that were not exposed to the antibiotic. Artemia nauplii and nematodes accumulated approximately 0.1 μg of the drug per nauplius and approximately 0.25 μg per nematode. They exhibited no signs of toxicity from exposure to the drug and contained the antibiotic in sufficient quantity to provide a theoretical therapeutic dose of the drug when fed to penaeid larvae.
In subsequent tests, normal and diseased larval Penaeus stylirostris readily accepted Romet-30 enriched Artemia . Diseased larvae fed the drug in this manner exhibited a statistically greater overall survival and a greater survival to the post-larval stage by Student's t -test at the 5% significance level. 相似文献
Romet-30 was added to groups of brine shrimp nauplii and nematodes in 1 L beakers to achieve a concentration of 3 mg of drug per ml of seawater. After a 4 h uptake period, predetermined numbers of organisms were assayed for antibiotic content using the micro-plate diffusion method and a Romet-30 sensitive strain of Vibrio alginolyticus as the indicator. The resulting zones of inhibition were compared to that of a standard Kirby-Bauer sensitivity disc containing 25 μg of the drug that was placed on each plate as standard control. Negative controls consisted of equal numbers of nauplii and nematodes that were not exposed to the antibiotic. Artemia nauplii and nematodes accumulated approximately 0.1 μg of the drug per nauplius and approximately 0.25 μg per nematode. They exhibited no signs of toxicity from exposure to the drug and contained the antibiotic in sufficient quantity to provide a theoretical therapeutic dose of the drug when fed to penaeid larvae.
In subsequent tests, normal and diseased larval Penaeus stylirostris readily accepted Romet-30 enriched Artemia . Diseased larvae fed the drug in this manner exhibited a statistically greater overall survival and a greater survival to the post-larval stage by Student's t -test at the 5% significance level. 相似文献
78.
Distribution and status of the Sumatran rhinoceros Dicerorhinus sumatrensis in Peninsular Malaysia were studied from 1975 to 1981. We compiled information collected from field surveys, interviews with people living near rhino areas, and the literature. Most potential rhino areas were surveyed on the ground to confirm the presence of animals, estimate numbers, and evaluate the status of the habitat. We confirmed that rhinos presently occur in ten isolated areas scattered throughout the Malay Peninsula. The number of rhinos is estimated at 50 to 75 animals with the Endau-Rompin (20–25), Taman Negara (8–12), and Sungai Dusun (4–6) areas containing the largest contiguous populations. The Sumatran rhino appears threatened with immediate extinction in Peninsular Malaysia. Excessive killing of rhinos because of the high commercial value of their body parts has greatly reduced numbers. Habitat destruction from logging and forest clearance has separated and isolated already small populations. We recommend that conservation efforts for this species in Malaysia be concentrated in the Endau-Rompin region because this population has the best chances for survival. 相似文献
79.
80.