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21.
We evaluated the histological features of the endometrium in relation to the bleeding pattern in a group of women receiving oral cyclical combined hormone replacement therapy (HRT), and compared the histological features with those of luteinizing hormone (LH)-dated endometrial biopsies obtained from healthy women at the time of sterilization. A total of 103 women completed 6 months of HRT therapy. All received a regimen of 2 mg oestradiol valerate daily, with 1 mg norethisterone added for the last 12 days of every 28-day cycle. Endometrial biopsies were scheduled for the end of the study (days 27-29 of the last cycle of therapy). Using the classical histological criteria, secretory endometrial changes were demonstrated in the majority (n = 89) of cases. The remaining were insufficient or inactive (n = 12), proliferative (n = 1) or atrophic (n = 1). Forty-nine women had a mean cycle length of less than 29 days (early bleeders), 50 women experienced cycles of more than 29 days (late bleeders) and four did not experience any bleeding. When the individual histological structures were examined, using image analysis, there were no statistically significant differences in the histological features when the long cycles in early bleeders were compared with those in late bleeders. LH-dated endometrium showed a high degree of homogeneity that was consistent with cycle day as described by the classic criteria, but HRT-treated endometrium exhibited a wide range of variability. HRT-treated endometrium from the subset of women who bled on or after day 29, and whose biopsies were obtained before the onset of bleeding, differed significantly from the endometrium taken at the corresponding phase of the physiological cycle. We conclude that the use of classical histological criteria, which are used in relation to the physiological cycle, in the study of HRT-treated endometria is inappropriate. 相似文献
22.
Structural Consequence of Non-Synonymous Single-Nucleotide Variants in the N-Terminal Domain of LIS1
Ho Jin Choi Sarmistha Mitra Yeasmin Akter Munni Raju Dash Sarmin Ummey Habiba Md Sohel Sultana Israt Jahan Tae Jung Jang Il Soo Moon 《International journal of molecular sciences》2022,23(6)
Disruptive neuronal migration during early brain development causes severe brain malformation. Characterized by mislocalization of cortical neurons, this condition is a result of the loss of function of migration regulating genes. One known neuronal migration disorder is lissencephaly (LIS), which is caused by deletions or mutations of the LIS1 (PAFAH1B1) gene that has been implicated in regulating the microtubule motor protein cytoplasmic dynein. Although this class of diseases has recently received considerable attention, the roles of non-synonymous polymorphisms (nsSNPs) in LIS1 on lissencephaly progression remain elusive. Therefore, the present study employed combined bioinformatics and molecular modeling approach to identify potential damaging nsSNPs in the LIS1 gene and provide atomic insight into their roles in LIS1 loss of function. Using this approach, we identified three high-risk nsSNPs, including rs121434486 (F31S), rs587784254 (W55R), and rs757993270 (W55L) in the LIS1 gene, which are located on the N-terminal domain of LIS1. Molecular dynamics simulation highlighted that all variants decreased helical conformation, increased the intermonomeric distance, and thus disrupted intermonomeric contacts in the LIS1 dimer. Furthermore, the presence of variants also caused a loss of positive electrostatic potential and reduced dimer binding potential. Since self-dimerization is an essential aspect of LIS1 to recruit interacting partners, thus these variants are associated with the loss of LIS1 functions. As a corollary, these findings may further provide critical insights on the roles of LIS1 variants in brain malformation. 相似文献
23.
Yacine Laalaoui Habiba Drias 《Soft Computing - A Fusion of Foundations, Methodologies and Applications》2011,15(6):1071-1086
We propose two novel heuristic search techniques to address the problem of scheduling tasks under hard timing constraints
on a single processor architecture. The underlying problem is NP-hard in the strong sense and it is a fundamental challenge
in feedback-control theory and automated cybernetics. The proposed techniques are a learning-based approaches and they take
much less memory space. A partial feasible schedule is maintained and extended over a repeated problem solving trials, previously
assigned priorities are refined according to the gained information about the problem to lead the convergence to a complete
feasible schedule if one exists. First, we present the learning in hard-real-time with single learning (LHRTS-SL) algorithm
where a single learning function is utilized, then we discuss its drawback and we propose the LHRTS with double learning algorithm
in which a second learning function is integrated to cope up with LHRTS-SL drawback. Experimental results show the efficiency
of the proposed techniques in terms of success ratio when used to schedule randomly generated problem instances. 相似文献
24.
An intrusion detection and alert correlation approach based on revising probabilistic classifiers using expert knowledge 总被引:1,自引:1,他引:0
Salem Benferhat Abdelhamid Boudjelida Karim Tabia Habiba Drias 《Applied Intelligence》2013,38(4):520-540
Bayesian networks are important knowledge representation tools for handling uncertain pieces of information. The success of these models is strongly related to their capacity to represent and handle dependence relations. Some forms of Bayesian networks have been successfully applied in many classification tasks. In particular, naive Bayes classifiers have been used for intrusion detection and alerts correlation. This paper analyses the advantage of adding expert knowledge to probabilistic classifiers in the context of intrusion detection and alerts correlation. As examples of probabilistic classifiers, we will consider the well-known Naive Bayes, Tree Augmented Naïve Bayes (TAN), Hidden Naive Bayes (HNB) and decision tree classifiers. Our approach can be applied for any classifier where the outcome is a probability distribution over a set of classes (or decisions). In particular, we study how additional expert knowledge such as “it is expected that 80 % of traffic will be normal” can be integrated in classification tasks. Our aim is to revise probabilistic classifiers’ outputs in order to fit expert knowledge. Experimental results show that our approach improves existing results on different benchmarks from intrusion detection and alert correlation areas. 相似文献
25.
Hydrogen energy production and dyes degradation have been considered the need of modern age of technology in globe irrespective of the level of science and research in that country. Hydrogen gas is a green energy fule for the future application and abunduntly available in environment. Various techniques are reported for the production of hydrogen energy among which photocatalysis method is envirnmental friendly, cost‐efficient method using water that also decontaminated from dyes, which is a main problem nowadays because of increase in industrial applications according to the living standards. The composite of Bismuth vanadate (BiVO4) with the coupling of the rduced graphene oxide (rGO) were synthezied by the facial hydrothermal technique by using a bismuth nitrate penta hydrate and amonium metavanadate as main precour and graphene oxide solution for reduced graphene oxide incorporation. X‐ray diffraction (XRD), Scanning Electron Microscope (SEM), ultraviolet adsorption spectroscopy (UV‐vis), and Brunauer‐Emmett‐Teller (BET) characterization tools investigate the role of concentration of the coupling material rGO in BiVO4. All characterization techniques confirms that 1.5% rGO/BiVO4 shows transformation of tetragonal to monoclinic phase with altration of the particles size (25‐40 nm), with high‐surface area, having irregular spherical porous clusters degradation of methelene blue (97%), production of green energy in the form of hydrogen gas fuel, and enhancement of the absorption of light that is clear intimation of the high photocatalytic efficiency towards the decontamination of the wastewater and production of hydrogen gas. Prepared nanostructured composite in current work reveals effective photocatalytic activity for decontamination of the wastewater and evolution of hydrogen energy would be the precise idea to utilize them in near future with various promising applications. 相似文献
26.
In this article, the effect of combined temperature‐concentration and shear rate conditions on the rheology of double‐walled carbon nanotubes (DWCNTs)/RTM6‐Epoxy suspension was investigated to determine the optimum processing conditions. The rheological behavior and cure kinetics of this nanocomposite are presented. Cure kinetics analysis of the epoxy resin and the epoxy resin filled with DWCNTs was performed using Differential Scanning Calorimeter (DSC) and parameters of the kinetics model were compared. The DWCNTs have an acceleration effect on the reaction rate of the epoxy resin but no significant effect is noted on the glass transition temperature of the epoxy resin. This study reveals that the effect of shear‐thinning is more pronounced at high temperatures when DWCNTs content is increased. In addition, the steady shear flow exhibits a thermally activated property above 60°C whereas the polymer fluid viscosity is influenced by the free volume and cooperative effects when the temperature is below 60°C. © 2012 Wiley Periodicals, Inc. J Appl Polym Sci, 2012 相似文献
27.
Michel Prud’homme Habiba Bougherara 《International Journal of Heat and Mass Transfer》2005,48(11):2278-2289
A weakly nonlinear stability analysis is developed for the unicellular natural convection pattern in a horizontal fluid layer heated by uniform crossed heat fluxes applied on the horizontal and vertical walls, the remaining walls being adiabatic. The critical Rayleigh number is determined, for different Prandtl numbers and heat flux ratios, from the analytical parallel approximation for the single cell flow. For the range of parameters considered, stable, supercritical bifurcations occur solely for longitudinal disturbances with three velocity components. Depending on the value of Pr and the heat flux ratio, the instability is oscillating and hydrodynamic at small Pr and thermal and steady for larger Pr. Computations of the Landau coefficients for the two interacting modes reveal that the hydrodynamic mode is the only stable mode at the codimension points. 相似文献
28.
A novel micromechanical approach is used to study the fatigue failure of unidirectional polymer matrix composites subject to off-axis loading. The main advantage of the present micromechanical model lies in its ability to give closed form solutions for the effective nonlinear response of unidirectional composites and to predict the material response to any combination of shear and normal loading. The fatigue failure criterion is expressed in terms of the fatigue failure functions of the constituent materials. The micromechanical model is also used to calculate these fatigue failure functions from the knowledge of the S–N diagrams of the composite material in longitudinal, transverse, and shear loadings; thus, eliminating the need for any further experimentation. Unlike previous works, the present study accounts for the viscoelasticity of the matrix material rendering it the capability of modeling creep damage accumulation in high-temperature composite materials. The results are found to be in good agreement with the literature. In particular, for higher off-axis angles, the results are seen to be in better concurrence with the experimental data compared to when the effect of viscoelasticity is overlooked. The present approach is also capable of accounting for the strain evolution due to viscoelasticity of the matrix material. 相似文献
29.
The present work deals with the study of efficacy of some treatments, namely soaking (in water and bicarbonate solution), ordinary and pressure cooking, germination and fermentation in reducing or removal of antinutritional factors usually present in cowpeas (protease inhibitors, tannins, phytic acid and flatus-producing oligosaccharides (raffinose and stachyose). The results showed that long-time soaking (16 h) in bicarbonate solution caused remarkable reduction in the antinutritional factors. Pressure cooking was more effective than ordinary. Cooking pregerminated cowpeas was most effective. Fermentation completely removed trypsin inhibitor, oligosaccharides and reduced remarkably phytic acid. However, tannins noticeably increased. 相似文献
30.
Nutrient content of complementary foods based on processed and fermented sorghum, groundnut, spinach, and mango 总被引:1,自引:0,他引:1
BACKGROUND: Many African mothers use gruels made of maize and sorghum as complementary foods for their infants because they cannot afford the cost of nutritionally superior commercial weaning foods. OBJECTIVE: To improve the nutritional quality of traditional sorghum gruels used as complementary foods for children between six months and five years in the northern part of Cameroon. METHODS: Sorghum grains were processed by dehulling, sprouting, dehulling and cooking, and sprouting and cooking, then fermented using Saccharomyces cerevisae and tested for nutritional quality. The processed samples were analyzed for their nutrient composition and the digestibility of proteins and carbohydrates. RESULTS: The resulting products showed a significant reduction in antinutritional factors (e.g., phenolic compounds and phytates). In addition, germination improved the in vitro digestibility of proteins and carbohydrates. These effects were enhanced by fermentation of the resulting sorghum flour, regardless of how grains were pretreated, although the protein and mineral content remained low. Use of a composite flour made from pretreated sorghum, groundnut, spinach, and mango improved the protein, mineral, and vitamin A and C content of the gruels. Fermentation of composite flours resulted in an improvement in the protein content. CONCLUSIONS: This study, conducted under local conditions and using local technology, describes an opportunity for improving the quality of complementary foods using local ingredients. 相似文献