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641.
Thirty-nine males and 18 females, in six groups, participated in six high altitude treks (each lasting 3–4 weeks and climbing up to 5500 m) in the Himalaya and Karakoram. Inverse relationships between mean overnight total insulation (sleeping bag plus clothing) and air temperature in tents were recorded for all treks. Average overnight thermal sensations varied little with air temperature as the subjects modified their clothing insulation to maintain thermal sensations warmer than ‘neutral’ for all treks. For combined treks, subjects adjusted their mean overnight total insulation up to 7 clo for thermal sensations of between 0 (‘neutral’) and +1 (‘slightly warm’) on average, measured on the standard seven-point thermal sensation scale developed for everyday low-altitude conditions. Very few subjects (3% of all daily responses, on average) reported ‘cool’ or ‘cold’ sensations. General tent discomfort increased with altitude suggesting that subjects interpreted tent comfort predominantly in terms of thermal outdoor conditions. 相似文献
642.
Quasiperiodic phases (quasicrystals) have been found in numerous alloy systems of aluminum with transition metals (TM) between about 60 and 85 at.% Al. In binary Al–TM systems only metastable quasicrystals were observed, while in several ternary systems containing Cu, Ni or Pd the quasicrystals are stable. Many stable and metastable periodic phases formed in these compositional ranges exhibit structural relations to quasicrystals. Studies of these phenomenona have stimulated extensive investigation or revision of the high-Al regions of the ternary alloy systems belonging to the Al–Cu–TM, Al–Ni–TM and Al–Pd–TM groups. These studies are reviewed here. 相似文献
643.
Laura Mourino-Alvarez Nerea Corbacho-Alonso Tamara Sastre-Oliva Cecilia Corros-Vicente Jorge Solis Teresa Tejerina Luis R. Padial Maria G. Barderas 《International journal of molecular sciences》2021,22(12)
Aortic stenosis (AS) and diabetes mellitus (DM) are both progressive diseases that if left untreated, result in significant morbidity and mortality. Several studies revealed that the prevalence of DM is substantially higher in patients with AS and, thus, the progression from mild to severe AS is greater in those patients with DM. DM and common comorbidities associated with both diseases, DM and AS, increase patient management complexity and make aortic valve replacement the only effective treatment. For that reason, a better understanding of the pathogenesis underlying both these diseases and the relationships between them is necessary to design more appropriate preventive and therapeutic approaches. In this review, we provided an overview of the main aspects of the relationship between AS and DM, including common comorbidities and risk factors. We also discuss the established treatments/therapies in patients with AS and DM. 相似文献
644.
Preethi Bala Balakrishnan Niccolò Silvestri Tamara Fernandez-Cabada Federica Marinaro Soraia Fernandes Sergio Fiorito Mario Miscuglio David Serantes Sergiu Ruta Karen Livesey Ondrej Hovorka Roy Chantrell Teresa Pellegrino 《Advanced materials (Deerfield Beach, Fla.)》2020,32(45):2003712
Nanoparticle-based magnetic hyperthermia is a well-known thermal therapy platform studied to treat solid tumors, but its use for monotherapy is limited due to incomplete tumor eradication at hyperthermia temperature (45 °C). It is often combined with chemotherapy for obtaining a more effective therapeutic outcome. Cubic-shaped cobalt ferrite nanoparticles (Co–Fe NCs) serve as magnetic hyperthermia agents and as a cytotoxic agent due to the known cobalt ion toxicity, allowing the achievement of both heat and cytotoxic effects from a single platform. In addition to this advantage, Co–Fe NCs have the unique ability to form growing chains under an alternating magnetic field (AMF). This unique chain formation, along with the mild hyperthermia and intrinsic cobalt toxicity, leads to complete tumor regression and improved overall survival in an in vivo murine xenograft model, all under clinically approved AMF conditions. Numerical calculations identify magnetic anisotropy as the main Co–Fe NCs’ feature to generate such chain formations. This novel combination therapy can improve the effects of magnetic hyperthermia, inaugurating investigation of mechanical behaviors of nanoparticles under AMF, as a new avenue for cancer therapy. 相似文献
645.
Yazeed Yasin Ghadi Nida Khalid Suliman A. Alsuhibany Tamara al Shloul Ahmad Jalal Jeongmin Park 《计算机、材料和连续体(英文)》2022,72(2):2597-2615
Human Activity Recognition (HAR) plays an important role in life care and health monitoring since it involves examining various activities of patients at homes, hospitals, or offices. Hence, the proposed system integrates Human-Human Interaction (HHI) and Human-Object Interaction (HOI) recognition to provide in-depth monitoring of the daily routine of patients. We propose a robust system comprising both RGB (red, green, blue) and depth information. In particular, humans in HHI datasets are segmented via connected components analysis and skin detection while the human and object in HOI datasets are segmented via saliency map. To track the movement of humans, we proposed orientation and thermal features. A codebook is generated using Linde-Buzo-Gray (LBG) algorithm for vector quantization. Then, the quantized vectors generated from image sequences of HOI are given to Artificial Neural Network (ANN) while the quantized vectors generated from image sequences of HHI are given to K-ary tree hashing for classification. There are two publicly available datasets used for experimentation on HHI recognition: Stony Brook University (SBU) Kinect interaction and the University of Lincoln's (UoL) 3D social activity dataset. Furthermore, two publicly available datasets are used for experimentation on HOI recognition: Nanyang Technological University (NTU) RGB-D and Sun Yat-Sen University (SYSU) 3D HOI datasets. The results proved the validity of the proposed system. 相似文献
646.
Tamara al Shloul Israr Akhter Suliman A. Alsuhibany Yazeed Yasin Ghadi Ahmad Jalal Jeongmin Park 《计算机、材料和连续体(英文)》2022,73(2):2389-2405
E-learning approaches are one of the most important learning platforms for the learner through electronic equipment. Such study techniques are useful for other groups of learners such as the crowd, pedestrian, sports, transports, communication, emergency services, management systems and education sectors. E-learning is still a challenging domain for researchers and developers to find new trends and advanced tools and methods. Many of them are currently working on this domain to fulfill the requirements of industry and the environment. In this paper, we proposed a method for pedestrian behavior mining of aerial data, using deep flow feature, graph mining technique, and convocational neural network. For input data, the state-of-the-art crowd activity University of Minnesota (UMN) dataset is adopted, which contains the aerial indoor and outdoor view of the pedestrian, for simplification of extra information and computational cost reduction the pre-processing is applied. Deep flow features are extracted to find more accurate information. Furthermore, to deal with repetition in features data and features mining the graph mining algorithm is applied, while Convolution Neural Network (CNN) is applied for pedestrian behavior mining. The proposed method shows 84.50% of mean accuracy and a 15.50% of error rate. Therefore, the achieved results show more accuracy as compared to state-of-the-art classification algorithms such as decision tree, artificial neural network (ANN). 相似文献
647.
The nucleoli and chromatin clumps of ovarian cells contain important features in discriminating malignant cells from normal ones. In geometric properties, the ovarian nucleoli and chromatin clumps appear as irregularly shaped dark spots in the nuclear images from specimens immunohistochemically stained with antibody to Mib-1. Malignant cells often have more active and larger nucleoli and chromatin clumps. However, estimating the size of the nucleoli or chromatin clumps is a difficult task since it is not easy to recognize and accurately separate the regions of nucleoli and chromatin clumps from the rest of the nuclei that are highly irregular and variant in contents and intensities. In this paper, we develop a method to derive a parameter called power ratio that is proportionally related to the size of nucleoli and chromatin clumps based on an ideal nuclear model without the region segmentation of nucleoli or chromatin clumps. Results of characterization of the parameter and comparison between malignant and normal cells are provided. 相似文献
648.
Hybrid composites of ABS with carbonaceous fillers for electromagnetic shielding applications
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Débora P. Schmitz Tamara I. Silva Sílvia D. A. S. Ramoa Guilherme M. O. Barra Alessandro Pegoretti Bluma G. Soares 《应用聚合物科学杂志》2018,135(29)
This work evaluates the influence of two types of carbonaceous fillers, carbon black (CB) and carbon nanotubes (CNTs), on the electrical, electromagnetic, and rheological properties of composites based on poly(acrylonitrile‐co‐butadiene‐co‐styrene) (ABS) prepared by the melt mixing. Electrical conductivity, electromagnetic shielding efficiency (EMI SE) in the X‐band frequency range (8–12.4 GHz), and melt flow index (MFI) results showed that ABS/CNT composites exhibit higher electrical conductivity and EMI SE, but lower MFI when compared to ABS/CB composites. The electrical conductivity of the binary composites showed an increase of around 16 orders of magnitude, when compared to neat ABS, for both fillers. Binary composites with 5 and 15 wt % of filler showed an EMI SE of, respectively, ?44 and ?83 dB for ABS/CNT, and ?9 and ?34 dB for ABS/CB. MFI for binary composites with 5 wt % were 15.45 and 0.55 g/10 min for CB and CNT, respectively. Hybrid composites ABS/CNT.CB with 3 wt % total filler and fraction 50:50 and 75:25 showed good correlation between EMI SE and MFI. © 2018 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018 , 135, 46546. 相似文献
649.
Binding of pyrene to hydrophobic fractions of dissolved organic matter: effect of polyvalent metal complexation 总被引:2,自引:0,他引:2
The effects of polyvalent metal cations on pyrene binding to hydrophobic acid and neutral fractions (HoA and HoN, respectively) of dissolved organic matter (DOM) were elucidated. The DOM was isolated from sewage sludge; pyrene binding was estimated from fluorescence measurements. Isotherms of pyrene binding to both fractions were nonlinear. Pyrene binding was higher for HoN due to the combined effect of greater hydrophobicity, aromaticity and the large molecular size of this fraction relative to HoA. The complexation of HoA with Cu2+, Al3+, and Fe3+ increased the binding of pyrene only when the HoA was equilibrated with polyvalent cations before pyrene was added. The maximal increase in pyrene binding to HoA was 56%, 64%, and 118% when pre-equilibrated with Cu2+, Fe3+, and Al3+, respectively. Pyrene binding to HoN was not affected by the presence of metal cations. HoA complexation with metal cations increased the apparent molecular size of this fraction. We suggest that the presence of metal cations induces the formation of pseudomicelles, which are more efficient in binding pyrene than the low-molecular-weight components. Our results demonstrate that HoA and HoN components can significantly affect the transport of organic contaminants in soils irrigated with treated wastewater or amended with sewage sludge. 相似文献
650.
The gastropod Littorina littorea (common periwinkle) is an abundant and widespread North Atlantic species. The characteristic development of Intersex in L. littorea has been widely applied as a biomarker for tributyltin (TBT) contamination. Here, we assess the potential of L. littorea as a novel sentinel species for evaluating the sublethal effects in wild populations of widely distributed contaminants. We collected animals from six sites across the South coast of England. Tissue concentrations of polycyclic aromatic hydrocarbons (PAHs), organotin compounds (OTCs), polychlorinated biphenyls (PCBs), and organochlorine pesticides (OCPs) were measured and compared with biomarkers of damage to DNA (Comet assay), lysosomal stability (NRR assay), and endocrine disruption (Intersex development). There was a strong correlation between DNA damage and PAH bioaccumulation (n=6, r=0.84, p<0.05), as well as that between Intersex development and OTC pollution (n=6, r=0.91, p<0.05). The relationship between PAH bioaccumulation and DNA strand breaks was nonlinear, highlighting the need to consider the role of adaptive mechanisms in the interpretation of field results. These results illustrate the potential use of periwinkles for monitoring a wide range of priority pollutants. 相似文献