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91.
Deterministic collect algorithms are presented that are adaptive to total contention and are efficient with respect to both the number of registers used and the step complexity. One of them has optimal O(k) step and O(n) space complexities, but assumes that processes’ identifiers are in O(n), where n is the total number of processes in the system and k is the total contention. The step complexity of an unrestricted name space variant of this algorithm remains O(k), but its space complexity increases to O(n 2).  相似文献   
92.
Cranberry constituents are known to exert anti-adhesion activity on H. pylori in vitro. To determine their possible additive effect to triple therapy with omeprazole, amoxicillin and clarithromycin (OAC), a double-blind randomized clinical study was carried out. One-hundred-seventy-seven patients with H. pylori infection treated with OAC for 1 week were randomly allocated to receive 250 mL of either cranberry juice (cranberry-OAC, n = 89) or placebo beverage (placebo-OAC, n = 88) twice daily and only cranberry juice or placebo beverage for the next 2 weeks. Treatment outcome was determined with the(13)C urea breath test ((13)C-UBT). An additional control group consisted of patients referred to the same center during the same period who were treated with OAC alone for 1 week (non-placebo-OAC, n = 712). Overall, the rate of H. pylori eradication ((13)C-UBT < 3.5) was 82.5%, with no statistically significant difference among the three arms. Analysis by gender revealed that for female subjects, the eradication rate was higher in the cranberry-OAC arm (n = 42, 95.2%) than in the placebo-OAC arm (n = 53, 86.8%) and significantly higher than in the non-placebo-OAC group (n = 425, 80%; p = 0.03). For males, the rate was nonsignificantly lower in the cranberry-OAC arm (n = 35, 73.9%) than in the placebo-OAC arm (n = 45, 80.0%) and non-placebo-OAC group (n = 287, 85.0%). These results suggest that the addition of cranberry to triple therapy improves the rate of H. pylori eradication in females.  相似文献   
93.
Data Mining, or knowledge discovery, is the computer-assisted process of digging through and analyzing large quantity of data in order to extract meaningful knowledge. Data mining methods are used in many studies to identify phenomena quicker and better than human experts. One class of these methods was designed for dealing with time series data. However, when several channels of data are collected simultaneously, data mining algorithms encounter numerous difficulties since channels may be measured in different units, may be recorded at different sampling-rates, or may have completely different characteristics. Furthermore, as the size of these data increases, the amount of irrelevant data usually increases as well and the process becomes impractical. Hence, in such cases, the analyst must be capable of focusing on the informational parts while ignoring the noise data. These kinds of difficulties complicate the analysis of multichannel data as compared to the analysis of single-channel data. This paper presents a useful technique for preprocessing multi channel data. Our technique supplies tools for coping with all the above-mentioned difficulties, and prepares the data for further analysis (using common algorithms, especially from the data mining field). The paper is divided as follows. After the introduction (Section I) we describe the state of the art (Section II), follows by the main section-methodology (Section III) which is divided to four steps (3.2-3.5). The results are described in a separate section (Section IV). Then, a discussion and conclusions of the proposed methodology are given in (Sections V and VI). Acknowledgements and the references follow.  相似文献   
94.
Galectin‐8 is a β‐galactoside‐recognising protein that has a role in the regulation of bone remodelling and is an emerging new target for tackling diseases with associated bone loss. We have designed and synthesised methyl 3‐O‐[1‐carboxyethyl]‐β‐d ‐galactopyranoside (compound 6 ) as a ligand to target the N‐terminal domain of galectin‐8 (galectin‐8N). Our design involved molecular dynamics (MD) simulations that predicted 6 to mimic the interactions made by the galactose ring as well as the carboxylic acid group of 3′‐O‐sialylated lactose (3′‐SiaLac), with galectin‐8N. Isothermal titration calorimetry (ITC) determined that the binding affinity of galectin‐8N for 6 was 32.8 μm , whereas no significant affinity was detected for the C‐terminal domain of galectin‐8 (galectin‐8C). The crystal structure of the galectin‐8N– 6 complex validated the predicted binding conformation and revealed the exact protein–ligand interactions that involve evolutionarily conserved amino acids of galectin and also those unique to galectin‐8N for recognition. Overall, we have initiated and demonstrated a rational ligand design campaign to develop a monosaccharide‐based scaffold as a binder of galectin‐8.  相似文献   
95.
Exposure to high ambient temperature is a stressor that influences both biological and behavioral functions and has been previously shown to have an extensive impact on brain structure and function. Physiological, cellular and behavioral responses to heat-stress (HS) (40–41 °C, 2 h) were evaluated in adult male Sprague-Dawley rats. The effect of HS exposure before predator-scent stress (PSS) exposure (i.e., HS preconditioning) was examined. Finally, a possible mechanism of HS-preconditioning to PSS was investigated. Immunohistochemical analyses of chosen cellular markers were performed in the hippocampus and in the hypothalamic paraventricular nucleus (PVN). Plasma corticosterone levels were evaluated, and the behavioral assessment included the elevated plus-maze (EPM) and the acoustic startle response (ASR) paradigms. Endogenous levels of heat shock protein (HSP)-70 were manipulated using an amino acid (L-glutamine) and a pharmacological agent (Doxazosin). A single exposure to an acute HS resulted in decreased body mass (BM), increased body temperature and increased corticosterone levels. Additionally, extensive cellular, but not behavioral changes were noted. HS-preconditioning provided behavioral resiliency to anxiety-like behavior associated with PSS, possibly through the induction of HSP-70. Targeting of HSP-70 is an attractive strategy for stress-related psychopathology treatment.  相似文献   
96.
97.
Biofiltration is a technology to treat urban stormwater runoff, which conveys pollutants, including heavy metals. However, the variability of metals removal performance in biofiltration systems is as yet unknown. A laboratory study has been conducted with vegetated biofilter mesocosms, partly fitted with a submerged zone at the bottom of the filter combined with a carbon source. The biofilters were dosed with stormwater according to three different dry/wet schemes, to investigate the effect of intermittent wetting and drying conditions on metal removal.Provided that the biofilters received regular stormwater input, metal removal exceeded 95%. The highest metal accumulation occurs in the top layer of the filter media. However, after antecedent drying before a storm event exceeding 3–4 weeks the filters performed significantly worse, although metal removal still remained relatively high. Introducing a submerged zone into the filter improved the performance significantly after extended dry periods. In particular, copper removal in filters equipped with a submerged zone was increased by around 12% (α = 0.05) both during wet and dry periods and for lead the negative effect of drying could completely be eliminated, with consistently low outflow concentrations even after long drying periods.  相似文献   
98.
In 3D TV research, one approach is to employ multiple cameras for creating a 3D multi-view signal with the aim to make interactive free-viewpoint selection possible in 3D TV media. This paper explores a new rendering algorithm that enables to compute a free-viewpoint between two reference views from existing cameras. A unique property is that we perform forward warping for both texture and depth simultaneously. Advantages of our rendering are manyfold. First, resampling artifacts are filled in by inverse warping. Second, disocclusions are processed while omitting warping of edges at high discontinuities. Third, our disocclusion inpainting approach explicitly uses depth information. We obtain an average PSNR gain of 3 dB and 4.5 dB for the ‘Breakdancers’ and ‘Ballet’ sequences, respectively, compared recently published results. Moreover, experiments are performed using compressed video from surrounding cameras. The overall system quality is dominated by rendering quality and not by coding.  相似文献   
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