887 research outputs found
Structural, elastic, mechanical and thermodynamic properties of Terbium oxide: First-principles investigations
First-principles investigations of the Terbium oxide TbO are performed on structural, elastic, mechanical and thermodynamic properties. The investigations are accomplished by employing full potential augmented plane wave FP-LAPW method framed within density functional theory DFT as implemented in the WIEN2k package. The exchange-correlation energy functional, a part of the total energy functional, is treated through Perdew Burke Ernzerhof scheme of the Generalized Gradient Approximation PBEGGA. The calculations of the ground state structural parameters, like lattice constants a0, bulk moduli B and their pressure derivative B′ values, are done for the rock-salt RS, zinc-blende ZB, cesium chloride CsCl, wurtzite WZ and nickel arsenide NiAs polymorphs of the TbO compound. The elastic constants (C11, C12, C13, C33, and C44) and mechanical properties (Young's modulus Y, Shear modulus S, Poisson's ratio σ, Anisotropic ratio A and compressibility β), were also calculated to comprehend its potential for valuable applications. From our calculations, the RS phase of TbO compound was found strongest one mechanically amongst the studied cubic structures whereas from hexagonal phases, the NiAs type structure was found stronger than WZ phase of the TbO. To analyze the ductility of the different structures of the TbO, Pugh's rule (B/SH) and Cauchy pressure (C12–C44) approaches are used. It was found that ZB, CsCl and WZ type structures of the TbO were of ductile nature with the obvious dominance of the ionic bonding while RS and NiAs structures exhibited brittle nature with the covalent bonding dominance. Moreover, Debye temperature was calculated for both cubic and hexagonal structures of TbO in question by averaging the computed sound velocities
INVESTIGATION OF Helicobacter pylori VIRULENCE GENOTYPE IN GASTRIC BIOPSIES BY PCR
  Background: Helicobacter pylori infections has been associated with the genetic diversity of their virulence factors, the virulence genotypes are valuable as molecular marker in the diagnosis of patients with bacterial infections . Our main objective was to analyze the frequency and allelic genotype of vacA , cagA also investigate another virulence genes of H. pylori. Methods: 75 biopsies of patients with gastritis and peptic ulcer diseases were selected to investigate the presences of H. pylori and collected from them antrum biopsies, then genomic DNA was extracted from antrum biopsies using genomic DNA kit .Subsequently, the virulence genes of H. pylori  were amplified using specific primers including vacA , cagA, cagE and oipA and iceA by PCR in 49 cases that positive to 16SrRNA which previously investigated. Results: A high prevalence of genes cagA (28.6%), vacAs1bm2 (56.8%), iceA2 (30.6%) and oipA (42.9%) was found, while  vacA s2m1  and iceA1 genotypes  was not found in our study.  There was significant correlation between the presence of cagA and cagE genotypes (p = 0.02), suggesting that these two genes almost used together as cag PAI integrity marker. The  presence of cagA gene was significantly associated with peptic ulceration (p ≤ 0.001), whereas different vacA genotypes or iceA2 genotype were no statistically significant with clinical outcome. Patients with peptic ulcer disease more likely to have oipA gene (61.9% ) than those with gastritis (38.1%), P = 0.037, also the presence oipA gene was statistically significant with presence iceA2. Conclusion : Most H. pylori genotypes which associated with peptic ulcer and gastritis were moderate virulent strains. Â
PREVENTIVE EFFECTS OF PHOENIX DACTYLIFERA POLYPHENOLS AGAINST 7,12-DIMETHYLBENZ(A)ANTHRACENE-INDUCED MAMMARY CANCER
Objectives: Polyphenols are vital micronutrients, in our diet, which have a role in the prevention of progressive cancer and cardiovascular diseases developing. The main objective of this research was to evaluate the hemopreventive effects of some polyphenols of Phoenix dactylifera pits on 7,12-dimethylbenz(a)anthracene (DMBA)-induced mammary cancer of female albino rats.Methods: The phenolics of P. dactylifera pits (Zahidi cultivar) were prepared by successive steps; extraction by ethanol:methanol:HCl:H2O, adsorption chromatography using a silica gel column and preparative high performers chromatography. The cytotoxic activity of the phenolics was detected against human breast cancer cell line (MCF-7). The acetone phenolic fraction, 50 female albino rats, and DMBA carcinogen were used to study the preventive effects.Results: The acetone phenolic fraction contained considerable amounts of the total phenolics and having antioxidant activity, which inhibit cancer cell line MCF-7 growth, and the inhibitory concentration 50% of cells (IC50) at 24 hrs was 202 μg/ml for MCF-7 and 480 μg/ml for WRL-68. The purified phenolic compounds may be related to genistein and quercetin derivatives that inhibited MCF-7 cell line growth and IC50 were 1030 and 203.9 μg/ml, respectively, compared with negligible effects on normal cell line. The acetone phenolic fraction prevented mammary cancer formation in the DMBA-induced rat model.Conclusions: The phenolics of date palm had chemopreventive effects against DMBA-induced mammary cancer, and they required further research to clarify the possible mechanisms that might have contributed to the preventive effects against mammary cancer
Environmental Impact of Petroleum Refinery Effluent on Groundwater Pollution: A Case Study of Maysan Refinery, Iraq
The study aimed to investigate the environmental impact of the refinery\u27s wastewater on groundwater within the refinery and the surrounding area. Six different testing sites were chosen to measure the concentrations of groundwater pollutants according to their distance from the untreated oil effluent discharge lagoon. The study period lasted for six months, as the testing work began in April and ended in September 2023. The results showed a clear effect of untreated petroleum effluent on the properties of groundwater, as the concentrations of petroleum effluent (oil and grease, TOC, phenol) and heavy metals (Ni, Cd, Pb) exceeded the permissible limits, as well as related parameters (TDS, EC, Cl, SO4) according to WHO specifications. As for the concentrations of the parameters (BOD, COD), there was no clear effect of the effluent on them, and on the contrary, their values began to increase at the testing sites far from the refinery. The groundwater was greatly affected by a distance of 5 km from the effluent collection lagoon (testing sites: GW1, GW2, GW3, and GW4), and it was not suitable for human use until after it was treated. As for the remaining of the distance (testing sites:GW5, GW6) to the nearest residential area (from 5 km to 9 km), the groundwater was limited to use for irrigation according to WQI guidelines. The study recommends that, in order to reduce pollution of refinery effluent, the responsible administration should use regular wastewater networks, construct a treatment plant for this effluent, and discharge the treated effluent to the nearest water sourc
Assessment of Thyroid Function in Infertile Iraqi Females
Infertility is one of the medical, social and psychological burdens in Iraqi society. Thyroid dysfunction can lead to menstrual disturbance, anovulatory cycle and decreased fertility. The study was designed to evaluate the role of thyroid disorders in infertility with emphasis on autoimmunity by Measuring T3, T4, TSH, & anti Thyroid peroxidase antibody in infertile females comparing the results with matching fertile controls. The study was conducted during the period from March 2015 to September 2015 at Karbala Maternity Hospital, infertility unit, and some private clinics. This study included a total number of 143 women in the reproductive age; ranging between (15- 43) years; divided into: The patients group included 92 infertile females; while controls were 51fertile females. The following parameters were measured for all study groups: T3, T4, TSH, &anti-TPO using ELISA device. The results showed that there were 60.8% of patients with primary infertility (n =56) while 38.2% were with secondary infertility (n= 36). There was a significant difference in T3, and Anti-TPO between patients and controls being higher in patients; (p-value <0.05). In addition; Anti-TPO level was significantly higher in secondary infertile patients compared to primary infertile patients. In conclusion; Thyroid disorders are closely related to infertility in Iraqi females; and Anti-TPO may be used as a biochemical indicator of subclinical thyroid disorders and may help in assessment of thyroid function as a cause of infertility whether primary or secondary. Keywords: Infertility, Thyroid disease, T3, T4, Anti-TP
A Proposed Approach for Object Detection and Recognition by Deep Learning Models Using Data Augmentation
Object detection and recognition play a crucial role in computer vision applications, ranging from security systems to autonomous vehicles. Deep learning algorithms have shown remarkable performance in these tasks, but they often require large, annotated datasets for training. However, collecting such datasets can be time-consuming and costly. Data augmentation techniques provide a solution to this problem by artificially expanding the training dataset. In this study, we propose a deep learning approach for object detection and recognition that leverages data augmentation techniques. We use deep convolutional neural networks (CNNs) as the underlying architecture, specifically focusing on popular models such as You Only Look Once version 3 (YOLOv3). By augmenting the training data with various transformations, such as rotation, scaling, and flipping, we can effectively increase the diversity and size of the dataset. Our approach not only improves the robustness and generalization of the models but also reduces the risk of overfitting. By training on augmented data, the models can learn to recognize objects from different viewpoints, scales, and orientations, leading to improved accuracy and performance. We conduct extensive experiments on benchmark datasets and evaluate the performance of our approach using standard metrics such as precision, recall, and mean average precision (mAP). The experimental results demonstrate that our data augmentation-based deep learning approach achieves superior object detection and recognition accuracy compared to traditional training methods without data augmentation. We compare the average accuracy of the YOLOv3-SPP model with two other variants of the YOLOv3 algorithm: one with a feature extraction network consisting of 53 convolutional layers and the other with 13 convolutional layers. The average accuracy of the proposed model (YOLOv3-SPP) is reported as accuracy of 97%, F1-score of 96%, precision of 94%, and average Intersection over Union (IoU) of 78.04%
Linear, Deterministic, and Order-Invariant Initialization Methods for the K-Means Clustering Algorithm
Over the past five decades, k-means has become the clustering algorithm of
choice in many application domains primarily due to its simplicity, time/space
efficiency, and invariance to the ordering of the data points. Unfortunately,
the algorithm's sensitivity to the initial selection of the cluster centers
remains to be its most serious drawback. Numerous initialization methods have
been proposed to address this drawback. Many of these methods, however, have
time complexity superlinear in the number of data points, which makes them
impractical for large data sets. On the other hand, linear methods are often
random and/or sensitive to the ordering of the data points. These methods are
generally unreliable in that the quality of their results is unpredictable.
Therefore, it is common practice to perform multiple runs of such methods and
take the output of the run that produces the best results. Such a practice,
however, greatly increases the computational requirements of the otherwise
highly efficient k-means algorithm. In this chapter, we investigate the
empirical performance of six linear, deterministic (non-random), and
order-invariant k-means initialization methods on a large and diverse
collection of data sets from the UCI Machine Learning Repository. The results
demonstrate that two relatively unknown hierarchical initialization methods due
to Su and Dy outperform the remaining four methods with respect to two
objective effectiveness criteria. In addition, a recent method due to Erisoglu
et al. performs surprisingly poorly.Comment: 21 pages, 2 figures, 5 tables, Partitional Clustering Algorithms
(Springer, 2014). arXiv admin note: substantial text overlap with
arXiv:1304.7465, arXiv:1209.196
Characterizing the morbid genome of ciliopathies
Background Ciliopathies are clinically diverse disorders of the primary cilium. Remarkable progress has been made in understanding the molecular basis of these genetically heterogeneous conditions; however, our knowledge of their morbid genome, pleiotropy, and variable expressivity remains incomplete. Results We applied genomic approaches on a large patient cohort of 371 affected individuals from 265 families, with phenotypes that span the entire ciliopathy spectrum. Likely causal mutations in previously described ciliopathy genes were identified in 85% (225/265) of the families, adding 32 novel alleles. Consistent with a fully penetrant model for these genes, we found no significant difference in their “mutation load” beyond the causal variants between our ciliopathy cohort and a control non-ciliopathy cohort. Genomic analysis of our cohort further identified mutations in a novel morbid gene TXNDC15, encoding a thiol isomerase, based on independent loss of function mutations in individuals with a consistent ciliopathy phenotype (Meckel-Gruber syndrome) and a functional effect of its deficiency on ciliary signaling. Our study also highlighted seven novel candidate genes (TRAPPC3, EXOC3L2, FAM98C, C17orf61, LRRCC1, NEK4, and CELSR2) some of which have established links to ciliogenesis. Finally, we show that the morbid genome of ciliopathies encompasses many founder mutations, the combined carrier frequency of which accounts for a high disease burden in the study population. Conclusions Our study increases our understanding of the morbid genome of ciliopathies. We also provide the strongest evidence, to date, in support of the classical Mendelian inheritance of Bardet-Biedl syndrome and other ciliopathies
Live Imaging of the Ependymal Cilia in the Lateral Ventricles of the Mouse Brain
Multiciliated ependymal cells line the ventricles in the adult brain. Abnormal function or structure of ependymal cilia is associated with various neurological deficits. The current ex vivo live imaging of motile ependymal cilia technique allows for a detailed study of ciliary dynamics following several steps. These steps include: mice euthanasia with carbon dioxide according to protocols of The University of Toledo’s Institutional Animal Care and Use Committee (IACUC); craniectomy followed by brain removal and sagittal brain dissection with a vibratome or sharp blade to obtain very thin sections through the brain lateral ventricles, where the ependymal cilia can be visualized. Incubation of the brain’s slices in a customized glass-bottom plate containing Dulbecco’s Modified Eagle’s Medium (DMEM)/High-Glucose at 37 °C in the presence of 95%/5% O2/CO2 mixture is essential to keep the tissue alive during the experiment. A video of the cilia beating is then recorded using a high-resolution differential interference contrast microscope. The video is then analyzed frame by frame to calculate the ciliary beating frequency. This allows distinct classification of the ependymal cells into three categories or types based on their ciliary beating frequency and angle. Furthermore, this technique allows the use of high-speed fluorescence imaging analysis to characterize the unique intracellular calcium oscillation properties of ependymal cells as well as the effect of pharmacological agents on the calcium oscillations and the ciliary beating frequency. In addition, this technique is suitable for immunofluorescence imaging for ciliary structure and ciliary protein localization studies. This is particularly important in disease diagnosis and phenotype studies. The main limitation of the technique is attributed to the decrease in live motile cilia movement as the brain tissue starts to die
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