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排序方式: 共有343条查询结果,搜索用时 15 毫秒
81.
Kinsinger CR Apffel J Baker M Bian X Borchers CH Bradshaw R Brusniak MY Chan DW Deutsch EW Domon B Gorman J Grimm R Hancock W Hermjakob H Horn D Hunter C Kolar P Kraus HJ Langen H Linding R Moritz RL Omenn GS Orlando R Pandey A Ping P Rahbar A Rivers R Seymour SL Simpson RJ Slotta D Smith RD Stein SE Tabb DL Tagle D Yates JR Rodriguez H 《Proteomics. Clinical applications》2011,5(11-12):580-589
Policies supporting the rapid and open sharing of proteomic data are being implemented by the leading journals in the field. The proteomics community is taking steps to ensure that data are made publicly accessible and are of high quality, a challenging task that requires the development and deployment of methods for measuring and documenting data quality metrics. On September 18, 2010, the U.S. National Cancer Institute (NCI) convened the "International Workshop on Proteomic Data Quality Metrics" in Sydney, Australia, to identify and address issues facing the development and use of such methods for open access proteomics data. The stakeholders at the workshop enumerated the key principles underlying a framework for data quality assessment in mass spectrometry data that will meet the needs of the research community, journals, funding agencies, and data repositories. Attendees discussed and agreed up on two primary needs for the wide use of quality metrics: (i) an evolving list of comprehensive quality metrics and (ii) standards accompanied by software analytics. Attendees stressed the importance of increased education and training programs to promote reliable protocols in proteomics. This workshop report explores the historic precedents, key discussions, and necessary next steps to enhance the quality of open access data. By agreement, this article is published simultaneously in Proteomics, Proteomics Clinical Applications, Journal of Proteome Research, and Molecular and Cellular Proteomics, as a public service to the research community. The peer review process was a coordinated effort conducted by a panel of referees selected by the journals. 相似文献
82.
This paper relates the second part of the investigation of air-cooling in concrete; the first part is presented in “Air cooling of concrete by means of embedded cooling pipes—Part I: Laboratory tests and heat transfer coefficients” [1]. Embedded cooling pipes are used to reduce the risk of thermal cracking in early age concrete. Traditionally, water has been used as a cooling medium, but air cooling has been shown to be advantageous for many applications. The experimentally-determined heat transfer coefficients of cooling pipes [1], have been used and verified in comparisons ofin situ measurements at the Igelsta Bridge in Södertälje, Sweden. The close agreement between measured and calculated temperatures of air-cooled sections seems to justify the use of the averaged heat transfer coefficients determined in [1]. Some exemplifying calculations are also shown, and the general behaviour of cooled structures is discussed. The principles of designing a cooling system for a general case are proposed. It is concluded that it is possible to design prismatic structures, such as a columns, by the use of existing models and measured heat transfer coefficients. 相似文献
83.
Air cooling of concrete by means of embedded cooling pipes-Part I: Laboratory tests of heat transfer coefficients 总被引:1,自引:0,他引:1
Embedded cooling pipes can be used to reduce the temperature rise in massive structures as a measure against thermal cracking. When air is used as a cooling medium, relatively large diameters with profiles causing friction losses along the pipe are preferred. In this paper, heat transfer coefficients for two different types of cooling pipes have been determined for different pipe flows in combination with various temperature levels. This paper relates to the first part of the investigation dealing with the laboratory tests of heat transfer coefficients. The second part, dealing with application in design, is presented in “Air cooling of concrete by means of embedded cooling pipes-Part II: Applications in design” [1]. 相似文献
84.
Teófilo Mazon Cardoso Patrik Oening Rodrigues Hellen Karine Stulzer Marcos Antonio Segatto Silva Jivaldo do Rosário Matos 《Drug development and industrial pharmacy》2013,39(7):631-637
Knowing the characteristics of raw materials in pharmaceutical practice is both important and useful. Firstly, evaluating the physical-chemical properties of the substances that will be used must be the primary step for quality control in the pharmacy industry. This work aims at analyzing the physical-chemical characteristics of two nimodipine samples I and II derived from distinct laboratories through thermal analysis (DSC and TG/DTG), HPLC, crystallography, and microscopy. Thermal analysis showed that sample II was more unstable than I. Morphological differences concerning shape, size, and crystallinity of particles were visualized by scanning electron microscopy (SEM) and X-ray powder diffraction. To sum up, the techniques used in this study can be said to have been efficient in the characterization and evaluation of quality control of the raw material. 相似文献
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87.
Hiroaki Tsuchiya Toshifumi Akaki Daisuke Terada Yuichiro Koizumi Patrik Schmuki Shinji Fujimoto 《Electrochimica acta》2009,54(22):5155-8801
The present work reports how metallurgical factors such as grain size and chemical composition of substrate affect the current behavior during anodization and the morphology of resulting formed oxide layers. The grain size of pure Ti sheet is controlled by the accumulative roll-bonding (ARB) process. Tubular oxide layers are formed on the ARB-processed Ti sheets with different grain sizes, but grain size does not affect the length, diameter of tubes and the degree of tube arrangement. The effect of chemical composition is examined using Ti-Zr alloys (Ti-20Zr, Ti-50Zr, Ti-80Zr) that can consist of a single phase, meaning that homogeneous tube formation can be achieved. With increasing Zr content in the alloys, tube diameter decreases while tube length increases. For the Ti-50Zr and Ti-80Zr, self-organization is achieved on two size scales, that is, nanotube arrays with two distinct diameters are observed. TEM observation revealed that anodic oxide layers are in crystalline state only in the case of pure Zr. 相似文献
88.
In vitro analysis of inflammatory responses following environmental exposure to pharmaceuticals and inland waters 总被引:2,自引:0,他引:2
Pharmaceuticals are regularly released into the environment; in particular non-steroidal anti-inflammatory drugs (NSAIDs) and antibiotics. Erythromycin, naproxen, furosemide and atenolol are reported to be stable for up to 1 year in the environment, which increases the risk for accumulation. In the present study we have measured the occurrence and concentration of pharmaceuticals in river Viskan (Jössabron) downstream of a sewage treatment plant in Borås, Sweden. Pharmaceuticals and water samples were tested for potential human risk by evaluating inflammatory responses (NF-κB and AP-1) using human T24 bladder epithelial cells and Jurkat T-cells. NF-κB activity in T24 cells was significantly reduced by all NSAIDs analysed (diclofenac, ketoprofen, naproxen, ibuprophen and dextropropoxyphene), but also by trimethoprim, using environmentally relevant concentrations. NF-κB and AP-1 activation was further analysed in response to water samples collected from different locations in Sweden. Dose-dependent down-regulation of AP-1 activity in Jurkat cells was observed at all locations. At two locations (Jössabron and Almenäs) down-regulation of NF-κB was observed. In contrast, the NF-κB response was potentiated by exposure to water from both locations following activation of NF-κB by treatment with heat-killed Escherichia coli. To determine the involvement of pharmaceuticals in the responses, T24 cells were exposed to the pharmaceutical mixture, based on the determined levels at Jössabron. This resulted in reduction of the NF-κB response following exposure to the pharmaceutical mixture alone while no potentiation was observed when cells were co-exposed to heat killed E. coli and pharmaceuticals. The obtained results demonstrate that the identified pharmaceuticals affect the inflammatory responses and furthermore indicate the presence of unknown substance(s) with the ability to potentiate inflammatory responses. 相似文献
89.
Nenad Gubeljak Jelena Vojvodi? Tuma Jo?ef Predan 《Engineering Fracture Mechanics》2007,74(6):995-1005
High-alloyed Cr-Ni-based two-phase stainless steel (SS) cast alloys are commonly used in nuclear power plants. The mechanical equipment in these facilities can contribute to a reduction in its resistance to stable crack growth as a result of extended operating times and high temperatures. The toughness of these materials strongly depends on their delta (δ) ferrite content, which spinodally decomposes into two phases with different ratios of Cr and Ni at a relatively low (slightly above 300 °C) temperature. This temperature is similar to the operating temperature of the vital parts, for example, the coolant system. The formation of two phases with the same crystal structure but different lattice parameters causes internal elastic stresses that result in a hardness increase and an impact-toughness decrease. The result is an increased risk of crack formation in the stress-concentration zones such as the critical regions of different welded joints (e.g. “L, T, K and X” shapes). The values of the critical stress intensity factor change according to its position along the crack contour. Therefore, the aim of our study was to assess the influence of the materials’ changes on the crack extension and the decrease of the primary pipeline’s bearing capacity by taking account of the increased temperature and time of operation for the given loading conditions. The SINTAP (European Structural Integrity Assessment Procedure) was used for this assessment. 相似文献
90.
Madalina Georgiana Necula Anca Mazare Andreea Mariana Negrescu Valentina Mitran Selda Ozkan Roxana Trusca Jung Park Patrik Schmuki Anisoara Cimpean 《International journal of molecular sciences》2022,23(7)
With the introduction of a new interdisciplinary field, osteoimmunology, today, it is well acknowledged that biomaterial-induced inflammation is modulated by immune cells, primarily macrophages, and can be controlled by nanotopographical cues. Recent studies have investigated the effect of surface properties in modulating the immune reaction, and literature data indicate that various surface cues can dictate both the immune response and bone tissue repair. In this context, the purpose of the present study was to investigate the effects of titanium dioxide nanotube (TNT) interspacing on the response of the macrophage-like cell line RAW 264.7. The cells were maintained in contact with the surfaces of flat titanium (Ti) and anodic TNTs with an intertube spacing of 20 nm (TNT20) and 80 nm (TNT80), under standard or pro-inflammatory conditions. The results revealed that nanotube interspacing can influence macrophage response in terms of cell survival and proliferation, cellular morphology and polarization, cytokine/chemokine expression, and foreign body reaction. While the nanostructured topography did not tune the macrophages’ differentiation into osteoclasts, this behavior was significantly reduced as compared to flat Ti surface. Overall, this study provides a new insight into how nanotubes’ morphological features, particularly intertube spacing, could affect macrophage behavior. 相似文献