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951.
Slip effects in plane porous journal bearings are considered realistically: only the slip coefficient is treated as an independent parameter and the porosity and the ratio of clearance to journal radius are the other factors which determine the effects of slip. The effects of velocity slip on the static performance as well as on the dynamic performance of the bearings are determined. 相似文献
952.
The purpose of this study is to develop a computer model of oscillatory contractions in isolated arteries from the tails of spontaneously hypertensive, stroke-prone rats (SHRSP). The computer simulation incorporates biologic data from experiments and mathematic expressions derived from an electric circuit model of the biologic system. The model characterizes the cellular mechanisms which have been proposed to be responsible for the oscillatory activity. Results indicate the ability of the model to provide results which closely match experimentally obtained data. 相似文献
953.
Syed Wasim Ali Farhat Waqar Muhammad Arif Malik Tariq Yasin Bashir Muhammad 《应用聚合物科学杂志》2013,129(4):2234-2243
Macroporus ethylacrylate‐divinylbenzene copolymers were synthesized by suspension polymerization using diethyl phthalate and n‐heptane as diluent. A hydrolysis study revealed that conversion of esters into carboxylic acid groups was dependent on three factors: (1) crosslinkage: increases with a decrease in crosslinkage, (2) reagent: sulfuric acid>aqueous NaOH>NaOH in a 1 : 1 water to ethylene glycol, and (3) pore volume (PV): highest when PV was ~ 0.7 mL g?1. Sulfuric acid hydrolyzed ester to ? COOH and introduced ? SO3H on phenyl rings, thus producing a bi‐functional resin. The functional groups were verified by IR spectroscopy and quantified by acid–base titration. The bi‐functional resin's capacity for toxic heavy metals in water samples was 12.51, 10.43, 9.43, 13.21, and 11.12 mg g?1 for Cu, Cd, Ni, Pb, and Zn, respectively and the recoveries exceeded >95% in range of pH 2–8, showing that it is suitable for water purification. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013 相似文献
954.
Influence of the angular shape of the volume-scattering function and multiple scattering on remote sensing reflectance 总被引:2,自引:0,他引:2
Scattering phase functions derived from measured (volume-scattering meter, VSM) volume-scattering functions (VSFs) from Crimean coastal waters were found to have systematic differences in angular structure from Fournier-Forand (FF) functions with equivalent backscattering ratios. Hydrolight simulations demonstrated that differences in the angular structure of the VSF could result in variations in modeled subsurface radiance reflectances of up to +/-20%. Furthermore, differences between VSM and FF simulated reflectances were found to be nonlinear as a function of scattering and could not be explained with the single-scattering approximation. Additional radiance transfer modeling demonstrated that the contribution of multiple scattering to radiance reflectance increased exponentially from a minimum of 16% for pure water to a maximum of approximately 94% for turbid waters. Monte Carlo simulations demonstrated that multiple forward-scattering events were the dominant contributors to the generation of radiance reflectance signals for turbid waters and that angular structures in the shape of the VSF at forward angles could have a significant influence in determining reflectance signals for turbid waters. 相似文献
955.
Gunhild von Amsberg Mirjam Zilles Wael Mansour Philipp Gild Winfried Alsdorf Moritz Kaune Lukas Bckelmann Jessica Hauschild Christoph Krisp Tina Rohlfing Ceren Saygi Malik Alawi Alexandra Zielinski Claudia Langebrake Su Jung Oh-Hohenhorst Sven Perner Derya Tilki Hartmut Schlüter Markus Graefen Sergey A. Dyshlovoy Carsten Bokemeyer 《International journal of molecular sciences》2022,23(23)
Significant progress has been achieved in the treatment of metastatic castration-resistant prostate cancer (mCRPC). However, results in patients with aggressive variant prostate cancer (AVPC) have been disappointing. Here, we report retrospectively collected data from intensively pretreated AVPC patients (n = 17; 88.2% visceral metastases; 82% elevation of neuroendocrine markers) treated with salvage chemotherapy consisting of cisplatin, ifosfamide, and paclitaxel (TIP). At the interim analysis, 60% of patients showed radiographic response or stable disease (PFS = 2.5 months; OS = 6 months). In men who responded to chemotherapy, an OS > 15 months was observed. Preclinical analyses confirmed the high activity of the TIP regimen, especially in docetaxel-resistant prostate cancer cells. This effect was primarily mediated by increased cisplatin sensitivity in the emergence of taxane resistance. Proteomic and functional analyses identified a lower DNA repair capacity and cell cycle machinery deficiency to be causative. In contrast, paclitaxel showed inconsistent effects, partially antagonizing cisplatin and ifosfamide in some AVPC models. Consequently, paclitaxel has been excluded from the TIP combination for future patients. In summary, we report for the first time the promising efficacy of TIP as salvage therapy in AVPC. Our preclinical data indicate a pivotal role for cisplatin in overcoming docetaxel resistance. 相似文献
956.
Christiane K. Bauer Tess Holling Denise Horn Mrio Nro Lao Ebtesam Abdalla Omneya Magdy Omar Malik Alawi Kerstin Kutsche 《International journal of molecular sciences》2022,23(17)
Dominant KCNQ1 variants are well-known for underlying cardiac arrhythmia syndromes. The two heterozygous KCNQ1 missense variants, R116L and P369L, cause an allelic disorder characterized by pituitary hormone deficiency and maternally inherited gingival fibromatosis. Increased K+ conductance upon co-expression of KCNQ1 mutant channels with the beta subunit KCNE2 is suggested to underlie the phenotype; however, the reason for KCNQ1-KCNE2 (Q1E2) channel gain-of-function is unknown. We aimed to discover the genetic defect in a single individual and three family members with gingival overgrowth and identified the KCNQ1 variants P369L and V185M, respectively. Patch-clamp experiments demonstrated increased constitutive K+ conductance of V185M-Q1E2 channels, confirming the pathogenicity of the novel variant. To gain insight into the pathomechanism, we examined all three disease-causing KCNQ1 mutants. Manipulation of the intracellular Ca2+ concentration prior to and during whole-cell recordings identified an impaired Ca2+ sensitivity of the mutant KCNQ1 channels. With low Ca2+, wild-type KCNQ1 currents were efficiently reduced and exhibited a pre-pulse-dependent cross-over of current traces and a high-voltage-activated component. These features were absent in mutant KCNQ1 channels and in wild-type channels co-expressed with calmodulin and exposed to high intracellular Ca2+. Moreover, co-expression of calmodulin with wild-type Q1E2 channels and loading the cells with high Ca2+ drastically increased Q1E2 current amplitudes, suggesting that KCNE2 normally limits the resting Q1E2 conductance by an increased demand for calcified calmodulin to achieve effective channel opening. Our data link impaired Ca2+ sensitivity of the KCNQ1 mutants R116L, V185M and P369L to Q1E2 gain-of-function that is associated with a particular KCNQ1 channelopathy. 相似文献
957.
958.
Orgren A.C. Dasgupta S. Rohrs C.E. Malik N.R. 《Signal Processing, IEEE Transactions on》1991,39(12):2629-2639
An effective adaptive scheme for noise cancellation when the signal to be recovered has known autocorrelation is presented. Two algorithms that exploit a special form of prior information are investigated. In this approach the desired signal is removed from the output feedback by linear prediction: the prior information used is the desired signal's autocorrelation. Knowing this, one can find a filter that whitens the desired signal. Screening the error feedback through this filter removes most of the desired signal energy, reducing its interference with the coefficient update. This is the basis for the first algorithm discussed, namely, the least-mean-square algorithm with augmented predictor (LMS-AP) proposed by Orgren et al. (1986). In many applications the whitening filter may not be strictly positive real (SPR). In such cases a different algorithm is needed; one which is assuredly convergent regardless of the satisfaction of the SPR condition. A modified LMS algorithm with augmented predictor (MLMS-AP) which provides such an alternative is proposed 相似文献
959.
Martin ebesta Hana Vojtkov Veronika Cyprichov Avinash P. Ingle Martin Urík Marek Kolen
ík 《International journal of molecular sciences》2023,24(1)
Fungi contain species with a plethora of ways of adapting to life in nature. Consequently, they produce large amounts of diverse biomolecules that can be generated on a large scale and in an affordable manner. This makes fungi an attractive alternative for many biotechnological processes. Ascomycetes and basidiomycetes are the most commonly used fungi for synthesis of metal-containing nanoparticles (NPs). The advantages of NPs created by fungi include the use of non-toxic fungus-produced biochemicals, energy efficiency, ambient temperature, pressure conditions, and the ability to control and tune the crystallinity, shape, and size of the NPs. Furthermore, the presence of biomolecules might serve a dual function as agents in NP formation and also capping that can tailor the (bio)activity of subsequent NPs. This review summarizes and reviews the synthesis of different metal, metal oxide, metal sulfide, and other metal-based NPs mediated by reactive media derived from various species. The phyla ascomycetes and basidiomycetes are presented separately. Moreover, the practical application of NP mycosynthesis, particularly in the fields of biomedicine, catalysis, biosensing, mosquito control, and precision agriculture as nanofertilizers and nanopesticides, has been studied so far. Finally, an outlook is provided, and future recommendations are proposed with an emphasis on the areas where mycosynthesized NPs have greater potential than NPs synthesized using physicochemical approaches. A deeper investigation of the mechanisms of NP formation in fungi-based media is needed, as is a focus on the transfer of NP mycosynthesis from the laboratory to large-scale production and application. 相似文献
960.
Th. Brenner J. Butterworth P. Geltenbort M. Hino S. S. Malik K. Okumura D. Sarkisov A. Steyerl M. Utsuro 《Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment》2000,440(3):722-728
We report experiments testing the question whether or not ultra-cold neutrons (UCN) stored in traps with total-reflecting walls are temporarily adsorbed to the walls. A hypothetical process of sticking to the walls is theoretically intriguing but it can apparently make plausible the puzzling observations made in UCN storage experiments over the years. 相似文献