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排序方式: 共有1005条查询结果,搜索用时 31 毫秒
991.
This article presents the development of a ball localization and tracking algorithm, that is to be applied in a highly dynamic table soccer environment. The described approach is based on an earlier survey paper on object tracking, where a general selection procedure on object detection and tracking techniques was proposed. Although the survey paper presents a variety of state estimation techniques for tracking, this article describes why these are not well suited for our specific application. For this reason, an IMM estimation technique is adopted that has not been applied in this highly dynamic context before. To evaluate the IMM estimator, it is compared to the well-known and commonly used Kalman filter, that has been optimally tuned for this specific application. 相似文献
992.
993.
Hepatocyte growth factor (HGF) regulates granulosa cell (GC) steroidogenesis and suppresses apoptosis in non-ovarian cells. The hypothesis was thus developed that intraovarian HGF supports folliculogenesis by mediating steroidogenesis and suppressing apoptosis. To investigate the latter, the anti-apoptotic actions of HGF were tested in GCs and follicles isolated from immature rats. Results showed that HGF suppressed apoptosis in GC and follicle cultures as visualized using apoptosis indicator dye, YO-PRO-1. Immunohistochemistry was used to investigate the distribution of HGF, c-met, and HGF activator (HGFA) protein during folliculogenesis in equine chorionic gonadotropin (eCG)-primed rats. Immunoreactive HGF content was the greatest in GCs within preantral follicles. Following eCG, large antral follicles showed elevated HGF staining in theca and interstitial cells when compared with GCs. Intense c-met staining was observed in GCs within non-primed small preantral follicles; following eCG, the level of c-met was diminished in GCs, but increased within theca and interstitial cells. Theca, interstitium, and GCs in non-primed and primed ovaries contained HGFA. Following eCG, HGFA was more apparent in theca cells and the interstitium when compared to that in GCs within large antral follicles. The presence of HGF, c-met, and HGFA in preantral follicles would potentially enable the anti-apoptotic effects of HGF that were observed in vitro to occur in vivo. Advanced folliculogenesis led to a change in the cellular distribution of the HGF, c-met, and HGFA, suggesting that the ovarian HGF system is hormonally regulated in vivo. 相似文献
994.
Sigg L Black F Buffle J Cao J Cleven R Davison W Galceran J Gunkel P Kalis E Kistler D Martin M Noël S Nur Y Odzak N Puy J Van Riemsdijk W Temminghoff E Tercier-Waeber ML Toepperwien S Town RM Unsworth E Warnken KW Weng L Xue H Zhang H 《Environmental science & technology》2006,40(6):1934-1941
Several techniques for speciation analysis of Cu, Zn, Cd, Pb, and Ni are used in freshwater systems and compared with respect to their performance and to the metal species detected. The analytical techniques comprise the following: (i) diffusion gradients in thin-film gels (DGT); (ii) gel integrated microelectrodes combined to voltammetric in situ profiling system (GIME-VIP); (iii) stripping chronopotentiometry (SCP); (iv) flow-through and hollow fiber permeation liquid membranes (FTPLM and HFPLM); (v) Donnan membrane technique (DMT); (vi) competitive ligand-exchange/stripping voltammetry (CLE-SV). All methods could be used both under hardwater and under softwater conditions, although in some cases problems with detection limits were encountered at the low total concentrations. The detected Cu, Cd, and Pb concentrations decreased in the order DGT > or = GIME-VIP > or = FTPLM > or = HFPLM approximately = DMT (>CLE-SV for Cd), detected Zn decreased as DGT > or = GIME-VIP and Ni as DGT > DMT, in agreement with the known dynamic features of these techniques. Techniques involving in situ measurements (GIME-VIP) or in situ exposure (DGT, DMT, and HFPLM) appear to be appropriate in avoiding artifacts which may occur during sampling and sample handling. 相似文献
995.
Carbonation of industrial alkaline residues can be used as a CO2 sequestration technology to reduce carbon dioxide emissions. In this study, steel slag samples were carbonated to a varying extent. Leaching experiments and geochemical modeling were used to identify solubility-controlling processes of major and trace elements, both with regard to carbonation mechanisms and the environmental properties of the (carbonated) steel slag. Carbonation was shown to reduce the leaching of alkaline earth metals (except Mg) by conversion of Ca-phases, such as portlandite, ettringite, and Ca-(Fe)-silicates into calcite, possibly containing traces of Ba and Sr. The leaching of vanadium increased substantially upon carbonation, probably due to the dissolution of a Ca-vanadate. The reactive surface area of Al- and Fe-(hydr)oxides increased with the carbonation degree, which tends to reduce the leaching of sorption-controlled trace elements. Sorption on Mn- (hydr)oxides was found to be required to adequately model the leaching of divalent cations, but was not influenced by carbonation. Consideration of these three distinct reactive surfaces and possible (surface) precipitation reactions resulted in adequate modeling predictions of oxyanion and trace metal leaching from (carbonated) steel slag. Hence, these surfaces exert a major influence on the environmental properties of both fresh and carbonated steel slag. 相似文献
996.
Timo Nuijens Elena Piva John A. W. Kruijtzer Dirk T. S. Rijkers Rob M. J. Liskamp Peter J. L. M. Quaedflieg 《Advanced Synthesis \u0026amp; Catalysis》2011,353(7):1039-1044
Chemoenzymatic peptide synthesis is potentially the most cost‐efficient technology for the synthesis of short and medium‐sized peptides with some important advantages. For instance, stoichiometric amounts of expensive coupling reagents are not required and racemisation does not occur rendering purification easier compared to chemical peptide synthesis. In this paper, a novel interconversion reaction of peptide C‐terminal α‐carboxamides into primary alkyl esters with alcalase was used to develop a fully enzymatic peptide synthesis strategy. For each elongation step a cost‐efficient amino acid carboxamide building block was used followed by the interconversion of the elongated peptide carboxamide to the corresponding primary alkyl ester. These peptide esters are the starting materials for the next enzymatic peptide elongation step. 相似文献
997.
Wim H. De Jong Danyel Jennen Peter H. J. Keizers Hennie M. Hodemaekers Jolanda P. Vermeulen Frank Bakker Paul Schwillens Marcel van Herwijnen Marlon Jetten Jos C. S. Kleinjans Robert E. Geertsma Rob J. Vandebriel 《International journal of molecular sciences》2022,23(13)
Resorbable tissue fillers for aesthetic purposes can induce severe complications including product migration, late swelling, and inflammatory reactions. The relation between product characteristics and adverse effects is not well understood. We hypothesized that the degree of cross-linking hyaluronic acid (HA) fillers was associated with the occurrence of adverse effects. Five experimental HA preparations similar to HA fillers were synthesized with an increasing degree of cross-linking. Furthermore, a series of commercial fillers (Perfectha®) was obtained that differ in degradation time based on the size of their particulate HA components. Cytotoxic responses and cytokine production by human THP-1-derived macrophages exposed to extracts of the evaluated resorbable HA fillers were absent to minimal. Gene expression analysis of the HA-exposed macrophages revealed the responses related to cell cycle control and immune reactivity. Our results could not confirm the hypothesis that the level of cross-linking in our experimental HA fillers or the particulate size of commercial HA fillers is related to the induced biological responses. However, the evaluation of cytokine induction and gene expression in macrophages after biomaterial exposure presents promising opportunities for the development of methods to identify cellular processes that may be predictive for biomaterial-induced responses in patients. 相似文献
998.
999.
M. A. Pasha Rob Deardon Abdur Rahim 《Quality and Reliability Engineering International》2023,39(3):732-751
The non-uniform inspection scheme obtained by the constant integrated hazard procedure overcomes the uniform scheme economically in optimal design of control charts. The comperative study is generalized in this paper to an optimization problem which looks for the optimal sampling points among all possible sampling schemes. The objective function is simplified here by modelling sequential time intervals as a family of functions of the first sampling interval, which also has been induced by the constant integrated hazard approach. The study demonstrates the model implementation through the economic design of and T2-Hotelling control charts, both under the two widely used process failure mechanisms, that is, Weibull and Chen distributions. A comprehensive numerical investigation illustrates the possibility of existence of sampling schemes which outperform the constant integrated hazard approach and emphasizes the necessity of further investigation into the solution procedure. 相似文献
1000.
Dr. Habib Bouguenina Dr. Andrea Scarpino Dr. Jack A. O'Hanlon Dr. Justin Warne Dr. Hannah Z. Wang Dr. Laura Chan Wah Hak Dr. Amine Sadok Dr. P. Craig McAndrew Dr. Mark Stubbs Dr. Olivier A. Pierrat Tamas Hahner Dr. Marc P. Cabry Dr. Yann-Vaï Le Bihan Dr. Costas Mitsopoulos Dr. Fernando J. Sialana Dr. Theodoros I. Roumeliotis Dr. Rosemary Burke Dr. Rob L. M. van Montfort Prof. Dr. Jyoti Choudhari Prof. Dr. Rajesh Chopra Dr. John J. Caldwell Prof. Dr. Ian Collins 《Chembiochem : a European journal of chemical biology》2023,24(23):e202300351
Small molecules inducing protein degradation are important pharmacological tools to interrogate complex biology and are rapidly translating into clinical agents. However, to fully realise the potential of these molecules, selectivity remains a limiting challenge. Herein, we addressed the issue of selectivity in the design of CRL4CRBN recruiting PROteolysis TArgeting Chimeras (PROTACs). Thalidomide derivatives used to generate CRL4CRBN recruiting PROTACs have well described intrinsic monovalent degradation profiles by inducing the recruitment of neo-substrates, such as GSPT1, Ikaros and Aiolos. We leveraged structural insights from known CRL4CRBN neo-substrates to attenuate and indeed remove this monovalent degradation function in well-known CRL4CRBN molecular glues degraders, namely CC-885 and Pomalidomide. We then applied these design principles on a previously published BRD9 PROTAC (dBRD9-A) and generated an analogue with improved selectivity profile. Finally, we implemented a computational modelling pipeline to show that our degron blocking design does not impact PROTAC-induced ternary complex formation. We believe that the tools and principles presented in this work will be valuable to support the development of targeted protein degradation. 相似文献