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排序方式: 共有192条查询结果,搜索用时 15 毫秒
51.
Kayla Kauffman Courtney S. Werner Georgia Titcomb Michelle Pender Jean Yves Rabezara James P. Herrera Julie Teresa Shapiro Alma Solis Voahangy Soarimalala Pablo Tortosa Randall Kramer James Moody Peter J. Mucha Charles Nunn 《Journal of the Royal Society Interface》2022,19(186)
Social and spatial network analysis is an important approach for investigating infectious disease transmission, especially for pathogens transmitted directly between individuals or via environmental reservoirs. Given the diversity of ways to construct networks, however, it remains unclear how well networks constructed from different data types effectively capture transmission potential. We used empirical networks from a population in rural Madagascar to compare social network survey and spatial data-based networks of the same individuals. Close contact and environmental pathogen transmission pathways were modelled with the spatial data. We found that naming social partners during the surveys predicted higher close-contact rates and the proportion of environmental overlap on the spatial data-based networks. The spatial networks captured many strong and weak connections that were missed using social network surveys alone. Across networks, we found weak correlations among centrality measures (a proxy for superspreading potential). We conclude that social network surveys provide important scaffolding for understanding disease transmission pathways but miss contact-specific heterogeneities revealed by spatial data. Our analyses also highlight that the superspreading potential of individuals may vary across transmission modes. We provide detailed methods to construct networks for close-contact transmission pathogens when not all individuals simultaneously wear GPS trackers. 相似文献
52.
Gallegos-Tintoré S Torres-Fuentes C Martínez-Ayala AL Solorza-Feria J Alaiz M Girón-Calle J Vioque J 《Journal of the science of food and agriculture》2011,91(9):1618-1624
BACKGROUND: Antioxidant and chelating activities were determined in protein hydrolysates that were produced by treating a protein isolate of a non‐toxic genotype of Jatropha curcas with the protease preparation alcalase. RESULTS: 50 min protein hydrolysate with a degree of hydrolysis of 31.7% showed highest antioxidant and chelating activity. These activities were also determined in six peptidic fractions that were separated by gel filtration chromatography of the 50 min hydrolysate. The lower‐molecular‐weight peptidic fractions had the highest antioxidant and chelating activities, which correlated with a higher content in antioxidant and chelating amino acids such as tyrosine and histidine. CONCLUSION: Results show that J. curcas represents a good source of bioactive peptides. This may be important for the revalorization of defatted J. curcas flour, a by‐product resulting form oil extraction for biodiesel production. This is especially important in Third World and developing countries such as Mexico. Copyright © 2011 Society of Chemical Industry 相似文献
53.
New polyurethane-type rigid foams from liquified wood powders 总被引:1,自引:0,他引:1
54.
Poizner Howard; Merians Alma S.; Clark Mary Ann; Macauley Beth; Rothi Leslie J. Gonzalez; Heilman Kenneth M. 《Canadian Metallurgical Quarterly》1998,12(2):163
Three-dimensional motion analyses were performed on trajectories of repetitive "slicing" gestures by 4 participants with left-hemisphere lesions and limb apraxia, 6 participants with right-hemisphere lesions, and 7 neurologically intact participants. Left hemispheric lesioned participants with apraxia, but not right hemispheric lesioned participants showed impaired coupling of spatial and temporal aspects of wrist trajectories and deficits in interjoint coordination. Both groups of brain-lesioned participants differed from control participants in the 3-D plane of the wrist motion. The deficits of some right hemispheric lesioned participants in controlling the plane of wrist motion may be a consequence of left hemispatial neglect with rightward deviations. In contrast, the deficits of apraxic participants in controlling wrist trajectories and coordinating joint motions seem to reflect a deficit in these participants for the movement plan. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
55.
Took depression and marital maladjustment measures of all 154 couples attending a clinic. Average age for men was 38 yrs, for women 35 yrs; average length of marriage was 19 yrs. A significant correlation between depression and marital maladjustment was found for self-report data and was replicated by therapists' ratings. Women were significantly more depressed than men though similar in average ratings of marital adjustment. Women's depression ratings were minimally related to their own their husbands' marital ratings. Men's depression ratings were related to both their own and their wives' marital ratings. Convergent validity was demonstrated for the Locke and Wallace Marital-Adjustment Test and the Beck Depression Inventory. Clinical implications of findings concerning both depression and marital maladjustment are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
56.
Alma’aitah Wafa’ Za’al Talib Abdullah Zawawi Osman Mohd Azam 《Multimedia Tools and Applications》2021,80(8):12175-12194
Multimedia Tools and Applications - Digital resource objects (DRO) are among the most valuable resources that store the accumulated knowledge of humankind. Nowadays, many organisations aim to make... 相似文献
57.
Abstract: This study investigated the influence of an oxygen‐enriched modified atmosphere packaging (HiOx: 80% O2/20% CO2) in comparison with air‐permeable polyvinylchloride (PVC) wrapping and partial vacuum (VP: 60%) packaging on the ability of myofibrils to imbibe water during retail display of fresh ground pork at 2 to 4 °C. Both HiOx and PVC muscles after 4 d showed maximum myofibril swelling and A‐band dissolution when isolated myofibrils were subjected to a graded series of salt solutions (0.2→0.4 M NaCl with 10‐mM sodium pyrophosphate, pH 6.2), while VP samples exhibited no remarkable change. Protein carbonyl content increased substantially from day 0 to 4 in all muscle samples. For HiOx, muscle hydration capacity increased linearly (P < 0.05) during storage up to 14 d, corresponding to protein carbonyl production. No significant changes in hydration properties were noted in VP muscle samples, which also maintained lower levels of protein oxidation, during storage up to 21 d. These results indicated that packaging in modified atmosphere with high levels of oxygen could result in increased protein oxidation but enhanced hydration capacity of fresh meat. Practical Application: Packaging of fresh meat, including ground pork, under an oxygen‐enriched atmosphere condition is widely used in the industry to preserve red color of meat. Results from the present study indicate that high oxygen packaging has a discordant effect on fresh ground pork: it enhances hydration but decreases water‐binding, and this seems to be caused by increased swelling of muscle fibers due to mild protein oxidation. Hence, it is advisable to employ a water‐binding agent in this type of packaging system so as to retain the moisture in stored fresh pork products while maintaining the color stability. 相似文献
58.
A Graphical Method Predicting the Compressive Strength of Toughened Unidirectional Composite Laminates 总被引:1,自引:0,他引:1
The in-plane shear and compressive properties of unidirectional (UD) HTS40/977-2 carbon fibre-toughened resin (CF/TR) laminates
are investigated. Scanning Electron microscopy (SEM) and optical microscopy are used to reveal the failure mechanisms developed
during compression. It is found that damage initiates by fibre microbuckling (a fibre instability failure mode) which then
is followed by yielding of the matrix to form a fibre kink band zone that leads to final fracture. Analytical models are briefly
reviewed and a graphical method, based on the shear response of the composite system, is described in order to estimate the
UD compressive strength. Predictions for the HTS40/977-2 system are compared to experimental measurements and to data of five
other unidirectional carbon fibre reinforced polymer (CFRP) composites that are currently used in aerospace and other structural
applications. It is shown that the estimated values are in a good agreement with the measured results. 相似文献
59.
60.
Stephan Rehm Sigeng Han Ismail Hassani Alma Sokocevic Hendrik R. A. Jonker Dr. Joachim W. Engels Prof. Dr. Harald Schwalbe Prof. Dr. 《Chembiochem : a European journal of chemical biology》2009,10(1):119-127
The protein parvulustat (Z‐2685) from Streptomyces parvulus comprises 78 amino acids and functions as a highly efficient α‐amylase inhibitor. Parvulustat shares 29.6 % overall amino acid sequence identity to the well‐known α‐amylase inhibitor tendamistat. Among the conserved residues are the two disulfide bridges (C9–C25, C43–C70) and the active‐site motif (W16, R17, Y18). Here, we report the high‐resolution NMR structure of parvulustat based on NOEs, J couplings, chemical shifts and hydrogen‐exchange data. In addition, we studied the dynamical properties of parvulustat by heteronuclear relaxation measurements. We compare the structure of parvulustat with the structure of tendamistat in terms of secondary structure elements, charges and hydrophobicity. The overall structural composition is very similar, but there are distinct differences including the active‐site region. These structural and dynamical differences indicate that for parvulustat an induced‐fit mechanism for binding to α‐amylase might take place, since the structure of tendamistat does not change upon binding to α‐amylase. 相似文献