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91.
An analysis technique to assess the viability of digital image correlation (DIC) in tracking the full‐field strains across the surface of hanging historic tapestries is presented. Measurement uncertainty related to the use of the inherent tapestry image in tracking displacements is investigated through use of “synthetic” deformation fields. The latter are generated by mapping the details of a given tapestry image into finite element analyses. The combination of self‐weight loading, material non‐linearity, and image specific heterogeneity (related to slit stitching, damage, and patch‐restorations) serve to generate a bespoke deformation field complex enough to assess the reliability of DIC measurements. Accuracy is evaluated by comparing measured results with the original known deformations. The technique demonstrates that the optimum imaging settings and the choice of subset size for DIC analysis are strongly influenced by the tapestry image and the goal of the measurement, they are found using a compromise between conflicting objectives: minimising measurement error while maximising resolution. 相似文献
92.
Qian Chen Quanyin Hu Elena Dukhovlinova Guojun Chen Sarah Ahn Chao Wang Edikan A. Ogunnaike Frances S. Ligler Gianpietro Dotti Zhen Gu 《Advanced materials (Deerfield Beach, Fla.)》2019,31(23)
Chimeric antigen receptor (CAR)‐redirected T lymphocytes (CAR T cells) show modest therapeutic efficacy in solid tumors. The desmoplastic structure of the tumor and the immunosuppressive tumor microenvironment usually account for the reduced efficacy of CAR T cells in solid tumors. Mild hyperthermia of the tumor reduces its compact structure and interstitial fluid pressure, increases blood perfusion, releases antigens, and promotes the recruitment of endogenous immune cells. Therefore, the combination of mild hyperthermia with the adoptive transfer of CAR T cells can potentially increase the therapeutic index of these cells in solid tumors. It is found that the chondroitin sulfate proteoglycan‐4 (CSPG4)‐specific CAR T cells infused in Nod scid gamma mice engrafted with the human melanoma WM115 cell line have superior antitumor activity after photothermal ablation of the tumor. The findings suggest that photothermal therapy facilitates the accumulation and effector function of CAR T cells within solid tumors. 相似文献
93.
The decomposition of FeS2, both as a single phase and as it exists in coal, has been studied between 250 and 350 °C, in hydrogen and nitrogen atmospheres, and in the presence of a coal-derived solvent. The first-order rate constant for decomposition of FeS2 at 350 °C with H2 alone is 6.7 × 10?1min?1; with H2 and coal-derived solvent, it is 5.5 × 10?2min?1; for FeS2 contained within coal, solvent and H2, it is 8.6 × 10?3min?1. Although the rate constant for decomposition is dependent upon temperature and the system, the activation energy in each case has been calculated to be 88 kJ mol?1. A mechanism consistent with these data is the thermal decomposition of FeS2 to produce Fe1?xS and S, followed by reaction of the sulphur with available hydrogen (from H2, solvent or coal) to form H2S. 相似文献
94.
Sridharshi Chintha Hewawitharana Frances Elizabeth Thompson Catherine M. Loria Warren Strauss Jyothi Nagaraja Lorrene Ritchie Karen Lucy Webb 《Nutrition journal》2018,17(1):111
Background
A dietary screener questionnaire (DSQ) was used to assess dietary outcomes among children in the Healthy Communities Study (HCS), a study of the relationships between programs and policies to prevent child obesity and child diet, physical activity and weight outcomes.Methods
To compare dietary intake estimates derived from the DSQ against those from the Automated Self-Administered 24-Hour Recalls for Children (ASA24-Kids) among children, a measurement error model, using structural equation modelling, was utilized to estimate slopes, deattenuated correlation coefficients, and attenuation factors by age and sex, ethnicity, and BMI status.Participants/setting
A randomly selected sub-sample of HCS participants aged 4–15 years in 130 communities throughout the U.S. who completed the DSQ and up to two ASA24-Kids recalls (n?=?656;13% of HCS participants).Results
For most nutrient/foods examined, the DSQ yielded larger mean intake estimates than the ASA24-Kids, and agreement between the two measures varied by food/nutrient, age and sex, ethnicity, and BMI category. Deattenuated correlation coefficients of 0.4 or greater were observed for added sugars from SSBs (0.54), fruits and vegetables (0.40), and dairy foods (0.50). Lower deattenuated correlation coefficients were seen for total added sugars (0.37), whole grains (0.34), and fiber (0.34). Attenuation factors were most severe for total added sugars intake among overweight children, and for several other dietary outcomes among children aged 9–11 years.Conclusions
The DSQ was found to be a tool with acceptable agreement with the ASA24-Kids for measuring multiple dietary outcomes of interest in the HCS, although there may be potential due to measurement error to underestimate results (bias towards the null). In future studies, measurement error modelling and regression calibration may be possible solutions to correct for bias due to measurement error in most food/nutrient intake estimates from the DSQ when used among children.95.
96.
INTRODUCTION: Although it is important that children at risk of developing elevated blood lead receive regular screening, attendance at screening programs is variable. A literature review was undertaken to better understand the factors that affect carers' decisions about whether or not to take their children for blood lead screening. METHOD: Electronic databases (Medline, EMBASE, CINAHL, Psychinfo) were searched to identify relevant publications, supported by reviewing reference lists of identified articles and searching with internet-based search engines. RESULTS: Thirty-four published studies dealing with blood lead screening rates were identified, of which only seven papers focused specifically on parent's attitudes to blood lead screening. The barriers to and enablers of screening for elevated blood lead levels appear to be similar to those identified for other screening programs. DISCUSSION: It is recommended that attendance at screening be routinely monitored, and that where participation is suboptimal further research be undertaken, in close co-operation with affected communities or sub-groups, to determine how best to encourage screening and to protect children from lead. It is important to minimize stigma and to ensure, as far as possible, that practical barriers such as lack of transport do not restrict access to screening programs. 相似文献
97.
Swaney William T.; Curley James P.; Champagne Frances A.; Keverne Eric B. 《Canadian Metallurgical Quarterly》2008,122(5):963
Sexual experience has marked and long-lasting effects on male behavior in mammals, regulating traits such as the anticipation and display of sexual behavior, aggression, and olfaction. The authors conducted urine preference, habituation-dishabituation, and partner choice tests with sexually experienced and naive male mice and found that wild-type males acquire adaptively significant preferences for the odors of receptive, estrous females with sexual experience, and that these preferences are matched by changes in main olfactory system responses involving the piriform cortex, as indicated by c-Fos expression. The authors also report that these experiential effects are disrupted in male mice carrying a knockout of the imprinted gene Peg3. This paternally expressed gene regulates maternal care and offspring development, but the authors here report that Peg3 mutant males suffer a complex olfactory deficit that affects estrous odor preferences and the responses of the main olfactory system to such odors. Peg3 appears to have evolved to regulate the experience-dependent preference for receptive females, an adaptive trait that would enhance male reproductive success and so potentially increase paternal transmission of this paternally expressed gene. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
98.
Lunkenheimer Erika S.; Dishion Thomas J.; Shaw Daniel S.; Connell Arin M.; Gardner Frances; Wilson Melvin N.; Skuban Emily M. 《Canadian Metallurgical Quarterly》2008,44(6):1737
The authors examined the longitudinal effects of the Family Check-Up (FCU) on parents' positive behavior support and children's school readiness competencies in early childhood. It was hypothesized that the FCU would promote language skills and inhibitory control in children at risk for behavior problems as an indirect outcome associated with targeted improvements in parents' positive behavior support. High-risk families in the Women, Infants, and Children Nutrition Program participated in a multisite preventive intervention study (N = 731) with 3 yearly assessments beginning at child age 2 years. Positive behavior support was measured using 4 indicators derived from at-home observations of parent-child interaction during semistructured tasks. Longitudinal structural equation models revealed that parents in families randomly assigned to the FCU showed improvements in positive behavior support from child age 2 to 3, which in turn promoted children's inhibitory control and language development from age 3 to 4, accounting for child gender, ethnicity, and parental education. Findings suggest that a brief, ecological preventive intervention supporting positive parenting practices can indirectly foster key facets of school readiness in children at risk. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
99.
Yang CG Barasoain I Li X Matesanz R Liu R Sharom FJ Yin DL Díaz JF Fang WS 《ChemMedChem》2007,2(5):691-701
A series of C2-modified 10-deacetyl-7-propionyl cephalomannine derivatives was designed, prepared, and biologically evaluated. Some C2 meta-substituted benzoate analogues showed potent activity against both drug-sensitive and drug-resistant tumor cells in which resistance is mediated through either P-gp overexpression or beta-tubulin mutation mechanisms. The taxoid 15 b and related compounds are of particular interest, as they are much more cytotoxic than paclitaxel, especially against drug-resistant tumor cells; they are able to kill both drug-resistant and drug-sensitive cells (low R/S ratio), and they have high affinity for beta-tubulin. Our research results led to an important hypothesis, that is, a taxane with very high binding affinity for beta-tubulin is able to counteract drug resistance, which may assist in future taxane-based drug-discovery efforts. 相似文献
100.
We analyzed the behavioral responses of the ants Camponotus rufipes and Solenopsis geminata towards all instars of Dione junio and Abananote hylonome. We also analyzed ant behavior towards hexane extracts of larvae and extracts of the spines and neck glands of the fifth instars of both species and identified the chemical compounds present. Larvae of both species were repellent to ants from the first instar onward. Later instars survived ant attacks better than earlier instars. The spines and neck glands of the larvae influenced the behavior of C. rufipes. The chemical compounds contained in the hexane extracts of whole first and fifth instars and in the spines and neck glands of fifth instars were principally carboxylic acids and terpenes. Further bioassays confirmed the repellent effect of some of these acids toward ants. 相似文献