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31.
Carlos A. ávila-Orta Zoe V. Qui?ones-Jurado Miguel A. Waldo-Mendoza Erika A. Rivera-Paz Víctor J. Cruz-Delgado José M. Mata-Padilla Pablo González-Morones Ronald F. Ziolo 《Materials》2015,8(11):7900-7912
Isotactic polypropylenes (iPP) with different melt flow indexes (MFI) were used to fabricate nanocomposites (NCs) with 10 wt % loadings of multi-wall carbon nanotubes (MWCNTs) using ultrasound-assisted extrusion methods to determine their effect on the morphology, melt flow, and electrical properties of the NCs. Three different types of iPPs were used with MFIs of 2.5, 34 and 1200 g/10 min. Four different NC fabrication methods based on melt extrusion were used. In the first method melt extrusion fabrication without ultrasound assistance was used. In the second and third methods, an ultrasound probe attached to a hot chamber located at the exit of the die was used to subject the sample to fixed frequency and variable frequency, respectively. The fourth method is similar to the first method, with the difference being that the carbon nanotubes were treated in a fluidized air-bed with an ultrasound probe before being used in the fabrication of the NCs with no ultrasound assistance during extrusion. The samples were characterized by MFI, Optical microscopy (OM), Scanning electron microscopy (SEM), Transmission electron microscopy (TEM), electrical surface resistivity, and electric charge. MFI decreases in all cases with addition of MWCNTs with the largest decrease observed for samples with the highest MFI. The surface resistivity, which ranged from 1013 to 105 Ω/sq, and electric charge, were observed to depend on the ultrasound-assisted fabrication method as well as on the melt flow index of the iPP. A relationship between agglomerate size and area ratio with electric charge was found. Several trends in the overall data were identified and are discussed in terms of MFI and the different fabrication methods. 相似文献
32.
Ragan McLeod Sunyoung Kim Sara Tomek Sara McDaniel 《Early child development and care》2019,189(8):1284-1291
Young children enter kindergarten with varying levels of readiness and abilities to learn. One factor that contributes to lower levels of school readiness is poverty. One timely, cost-effective, and feasible strategy to boost school readiness, regardless of exposure to high-quality preschool is to leverage the summer months prior to kindergarten entry and provide comprehensive, evidence-based programming immediately before the school year begins. The current study implemented a community-based summer programme targeted at improving school readiness for 25 four- and five-year-old children in a low-income community. Across the 9-week study, children participated in two types of early literacy activities and the Incredible Years social/emotional learning curriculum. Results indicate that participants demonstrated significant growth across three early literacy skills and were rated as overall stable regarding their behaviour across the summer. These results are discussed along with implications and future directions in this line of research. 相似文献
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Marco Maruzzo Umberto Basso Eugenio Borsatti Laura Evangelista Filippo Alongi Orazio Caffo Francesca Maines Sara Galuppo Rocco De Vivo Fable Zustovich Dario Palleschi Andrea Zivi Teodoro Sava Mariella Sorarù Roberto Iacovelli Maurizio Nicodemo Susanne Baier Lucia Fratino Vittorina Zagonel 《Clinical genitourinary cancer》2019,17(1):e187-e194
Background
Radium 223 was introduced for metastatic castration-resistant prostate cancer based on the results of a randomized controlled trial showing risk reduction for death and skeletal events. Our aim was to evaluate the outcome of patients receiving radium 223 in a real-world setting.Patients and Methods
We conducted a multicenter retrospective analysis in the Triveneto region of Italy.Results
One hundred fifty-eight patients received radium 223 in our region. After a median follow-up of 9.5 months, 75 patients died. The median overall survival (OS) was 14.2 months, and the median progression-free survival (PFS) was 6.2 months. Seventy-one (45%) patients achieved progression as best response. Thirty-seven (23%) patients stopped the treatment early because of progression. Eastern Cooperative Oncology Group performance status was prognostic for OS (18.4 vs. 12.3 vs. 7.5 months; 0 vs. 1, P = .0062; 0 vs. 2, P = .0002), whereas previous prostatectomy or docetaxel exposure were not. A neutrophil to lymphocytes ratio ≥ 3 significantly impacted OS (18.1 vs. 9.7 months; P < .001) and slightly impacted PFS (6.6 vs. 5.6 months; P = .05). Patients with a baseline alkaline phosphatase (ALP) value ≥ 220 U/L had worse OS and PFS (24.1 vs. 10.5 months; 7.2 vs. 5.5 months; P < .001). Patients with changes in ALP value achieved better OS (P = .029) and PFS (P = .002). There was no difference according to the line of therapy (0 vs. ≥ 1; P = .490). The main grade 3/4 toxicities were anemia, asthenia, and thrombocytopenia.Conclusion
This large real-world report confirms comparable OS and PFS data when compared with the pivotal study, as well as the predictive role of ALP and neutrophil to lymphocytes ratio. The definition of the optimal position of radium 223 in the treatment of metastatic castration-resistant prostate cancer has still to be defined. 相似文献35.
An important part of fundamental research in catalysis is based on theoretical and modeling foundations which are closely connected with studies of single-crystalline catalyst surfaces. These so-called model catalysts are often prepared in the form of epitaxial thin films, and characterized using advanced material characterization techniques. This concept provides the fundamental understanding and the knowledge base needed to tailor the design of new heterogeneous catalysts with improved catalytic properties. The present contribution is devoted to development of a model catalyst system of CeO2 (ceria) on the Cu(111) substrate. We propose ways to experimentally characterize and control important parameters of the model catalyst—the coverage of the ceria layer, the influence of the Cu substrate, and the density of surface defects on ceria, particularly the density of step edges and the density and the ordering of the oxygen vacancies. The large spectrum of controlled parameters makes ceria on Cu(111) an interesting alternative to a more common model system ceria on Ru(0001) that has served numerous catalysis studies, mainly as a support for metal clusters. 相似文献
36.
Rubens Souza de OLIVEIRA Lanna Jamile Corrêa da COSTA Fernanda Atanaena Gon?alves de ANDRADE Wilson UIEDA Luzia Fátima Alves MARTORELLI Ana Paula de Arruda Geraldes KATAOKA Elizabeth Salbé Travassos da ROSA Pedro Fernando da Costa VASCONCELOS Armando de Souza PEREIRA Ant?nio Ismael Barros do CARMO Marcus Emanuel Barroncas FERNANDES 《Revista do Instituto de Medicina Tropical de S?o Paulo》2015,57(6):497-503
The outbreaks of rabies in humans transmitted by Desmodus rotundus in 2004 and 2005,
in the northeast of the Brazilian State of Para, eastern Amazon basin, made this a
priority area for studies on this zoonosis. Given this, the present study provides
data on this phenomenon in an urban context, in order to assess the possible
circulation of the classic rabies virus (RABV) among bat species in Capanema, a town
in the Amazon basin. Bats were collected, in 2011, with mist nets during the wet and
dry seasons. Samples of brain tissue and blood were collected for virological and
serological survey, respectively. None of the 153 brain tissue samples analyzed
tested positive for RABV infection, but 50.34% (95% CI: 45.67-55.01%) of the serum
samples analyzed were seropositive. Artibeus planirostris was the most common
species, with a high percentage of seropositive individuals (52.46%, 95% CI: 52.31
52.60%). Statistically, equal proportions of seropositive results were obtained in
the rainy and dry seasons (c2 = 0.057, d.f. = 1, p = 0.88). Significantly
higher proportions of males (55.96%, 95% CI: 48.96-62.96%) and adults (52.37%, 95%
CI: 47.35-57.39%) were seropositive. While none of the brain tissue samples tested
positive for infection, the high proportion of seropositive specimens indicates that
RABV may be widespread in this urban area. 相似文献
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39.
Lars J Vatten Tom I L Nilsen P?l R Romundstad Wenche B Dr?yvold Jostein Holmen 《European journal of cardiovascular prevention and rehabilitation》2006,13(6):909-915
OBJECTIVE: To investigate whether cardiovascular mortality related to obesity could be modified by physical activity. DESIGN: Mortality follow-up. SETTING: Population study. PARTICIPANTS: Participants in a health survey: 34 868 women and 32 872 men free from known cardiovascular disease or diabetes at baseline. MAIN OUTCOME MEASURES: Total cardiovascular mortality. MAIN RESULTS: During 16 years of follow-up, 3026 women and 3526 men had died from cardiovascular causes. In middle age, obesity [body mass index (BMI) of 30 or higher] was associated with increased risk of cardiovascular death, but the association weakened with age. After 70, there was no association between BMI and cardiovascular death. At all ages, a lower level of physical activity was associated with a higher cardiovascular mortality. In women with high physical activity, indicated by at least 30 min of moderate to vigorous activity more than once a week, cardiovascular mortality was only slightly higher in the obese compared to lean women (adjusted relative risk, 1.27; 95% confidence interval, 0.80-2.00). In men with high physical activity, cardiovascular mortality was, however, significantly higher among the obese (relative risk, 1.62; 95% confidence interval, 1.09-2.40). In both genders cardiovascular mortality was substantially higher in obese people who reported no regular physical activity compared to obese people with a high level of physical activity. CONCLUSION: In obese women, being highly active may, to a large extent, compensate for the risk-increasing effect of being obese, whereas in obese men who engage in a high level of physical activity, the risk of cardiovascular death may be higher than in lean and equally active men. 相似文献
40.
Jaros?aw Felu? Wojciech Rad?o Bart?omiej Kowalczyk 《Chirurgia narzadów ruchu i ortopedia polska》2006,71(2):107-112
Nine wrists in eight patients were treated surgically between 1988 and 2003 for symptomatic Madelung's deformity. The pain of involved wrist followed by forearm deformation fulfilled criteria for surgery. Closing wedge osteotomy of the distal radius were carried out eight times accompanied by shortening of the ulna (four patients), excision of the distal ulna (one patient), and no ulnar surgery (three patients). Pain relieved after surgery. The follow up period ranged from 1 to 9.5 years. No pour results were stated in subjective patient's estimation during final check up. Wrist appearance were stated to be satisfactory. Limitation of the range of motion concerning supination and pronation of the forearm were stated invariably. X-ray retrospective assessment of the inclination angle, lunate coverage and presence of arthritic changes were conducted. Time and method of surgical treatment for Madelung's deformity should be considered individually. 相似文献