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511.
The effect of load mass and its placement on postural sway 总被引:1,自引:0,他引:1
The purpose of this study was to investigate the effects of increasing load on postural sway in two different carrying positions: backpack and waist jacket. Potential differences between males and females were additionally evaluated. 60 young college students participated in this study, and were assigned to backpack and waist jacket groups. The loads in both groups were 12, 21 and 30 kg. Stabilometry was used to assess the amount of postural sway. The medio-lateral and antero-posterior mean sway, mean velocity, medio-lateral and antero-posterior path length and sway area of the centre of pressure position were calculated.In the backpack group all analyzed sway parameters linearly increased with additional load, the differences were significant at p < 0.001. However no significant change of the analyzed parameters was found when the subjects carried additional load in the waist jacket.Our results indicate that postural sway depends on the amount of the load carried in a backpack. Additionally, the position of the load is of significant importance. Carrying weight in a backpack increases postural sway with increasing weight whereas carrying weight in a waist jacket does not influence the amount of postural sway. There are no significant differences in the response to the amount and configuration of the load between male and female subjects. 相似文献
512.
沙发作为客厅中必不可少的家具配置,在人们的生活中起到了越来越重要的作用,中式风格的沙发在日常生活中越来越普遍。本文通过对中式沙发的起源,及中式沙发的类型、设计进行了介绍,指出中式沙发顺应了当前重视文化的时代背景和现代的生活方式,弘扬了中国传统文化和民族特色。 相似文献
513.
We present a system for rapidly and easily building instructable and self-adaptive software agents that retrieve and extract information. Our Wisconsin Adaptive Web Assistant (WAWA) constructs intelligent agents by accepting user preferences in the form of instructions. These user-provided instructions are compiled into neural networks that are responsible for the adaptive capabilities of an intelligent agent. The agent’s neural networks are modified via user-provided and system-constructed training examples. Users can create training examples by rating Web pages (or documents), but more importantly WAWA’s agents uses techniques from reinforcement learning to internally create their own examples. Users can also provide additional instruction throughout the life of an agent. Our experimental evaluations on a ‘home-page finder’ agent and a ‘seminar-announcement extractor’ agent illustrate the value of using instructable and adaptive agents for retrieving and extracting information. 相似文献
514.
Adam F. Lee Patrick J. Sears Steve D. Pollington Tina L. Overton Peter B. Wells Darren F. Lee 《Catalysis Letters》2000,70(3-4):183-186
The partial oxidation of isobutene has been studied over titania-supported uranium oxide catalysts which exhibit a strong synergy between UOx and support phases. 相似文献
515.
516.
The behavior of a photovoltaic (PV) panel submerged in water is studied. A sizeable increase of electric power output is found for shallow water. Experiments have been carried out for single crystalline silicon panels. Results are discussed and the increase in efficiency is investigated and understood. Operating problems are analyzed and the advantages of using underwater solar panels are pointed out. 相似文献
517.
Victor Hussling Romina H. Aspera-Werz Helen Rinderknecht Fabian Springer Christian Arnscheidt Maximilian M. Menger Tina Histing Andreas K. Nussler Sabrina Ehnert 《International journal of molecular sciences》2021,22(6)
A large British study, with almost 3000 patients, identified diabetes as main risk factor for delayed and nonunion fracture healing, the treatment of which causes large costs for the health system. In the past years, much progress has been made to treat common complications in diabetics. However, there is still a lack of advanced strategies to treat diabetic bone diseases. To develop such therapeutic strategies, mechanisms leading to massive bone alterations in diabetics have to be well understood. We herein describe an in vitro model displaying bone metabolism frequently observed in diabetics. The model is based on osteoblastic SaOS-2 cells, which in direct coculture, stimulate THP-1 cells to form osteoclasts. While in conventional 2D cocultures formation of mineralized matrix is decreased under pre-/diabetic conditions, formation of mineralized matrix is increased in 3D cocultures. Furthermore, we demonstrate a matrix stability of the 3D carrier that is decreased under pre-/diabetic conditions, resembling the in vivo situation in type 2 diabetics. In summary, our results show that a 3D environment is required in this in vitro model to mimic alterations in bone metabolism characteristic for pre-/diabetes. The ability to measure both osteoblast and osteoclast function, and their effect on mineralization and stability of the 3D carrier offers the possibility to use this model also for other purposes, e.g., drug screenings. 相似文献
518.
Sheng Zhu Victor Hussling Romina H. Aspera-Werz Tao Chen Bianca Braun Weidong Weng Tina Histing Andreas K. Nussler 《International journal of molecular sciences》2021,22(1)
Co-culture models have become mandatory for obtaining better insights into bone homeostasis, which relies on the balance between osteoblasts and osteoclasts. Cigarette smoking (CS) has been proven to increase the risk of osteoporosis; however, there is currently no proven treatment for osteoporosis in smokers excluding cessation. Bisphosphonates (BPs) are classical anti-osteoclastic drugs that are commonly used in examining the suitability of bone co-culture systems in vitro as well as to verify the response to osteoporotic stimuli. In the present study, we tested the effects of BPs on cigarette smoke extract (CSE)-affected cells in the co-culture of osteoblasts and osteoclasts. Our results showed that BPs were able to reduce CSE-induced osteoporotic alterations in the co-culture of osteoblasts and osteoclasts such as decreased matrix remodeling, enhanced osteoclast activation, and an up-regulated receptor activator of nuclear factor (NF)-kB-ligand (RANKL)/osteoprotegerin (OPG) ratio. In summary, BPs may be an effective alternative therapy for reversing osteoporotic alterations in smokers, and the potential mechanism is through modulation of the RANKL/OPG ratio. 相似文献
519.
Felix Bürkel Tina Jost Markus Hecht Lucie Heinzerling Rainer Fietkau Luitpold Distel 《International journal of molecular sciences》2020,21(23)
CC-115 is a dual inhibitor of the mechanistic target of rapamycin (mTOR) kinase and the DNA-dependent protein kinase (DNA-PK) that is currently being studied in phase I/II clinical trials. DNA-PK is essential for the repair of DNA-double strand breaks (DSB). Radiotherapy is frequently used in the palliative treatment of metastatic melanoma patients and induces DSBs. Melanoma cell lines and healthy-donor skin fibroblast cell lines were treated with CC-115 and ionizing irradiation (IR). Apoptosis, necrosis, and cell cycle distribution were analyzed. Colony forming assays were conducted to study radiosensitizing effects. Immunofluorescence microscopy was performed to determine the activity of homologous recombination (HR). In most of the malign cell lines, an increasing concentration of CC-115 resulted in increased cell death. Furthermore, strong cytotoxic effects were only observed in malignant cell lines. Regarding clonogenicity, all cell lines displayed decreased survival fractions during combined inhibitor and IR treatment and supra-additive effects of the combination were observable in 5 out of 9 melanoma cell lines. CC-115 showed radiosensitizing potential in 7 out of 9 melanoma cell lines, but not in healthy skin fibroblasts. Based on our data CC-115 treatment could be a promising approach for patients with metastatic melanoma, particularly in the combination with radiotherapy. 相似文献
520.