563 research outputs found
Fracture toughness of matrix cracked FRC and FGC beams using equivalent TPFM
In the present work, the fracture toughness (KIC) of full-depth (FD) fiber-reinforced concrete (FRC) and layered functionally graded concrete (FGC) matrix cracked (MC) beams has been determined by the equivalent relationships of the two-parameter fracture model (ETPFM). Forty-eight MC-FGC and MC-FD FRC beam specimens with span-depth ratios (L/d) equal 4, 5, and 6 were tested under the 3PB configuration. The MC length-depth ratio (ao/d) remained constant equal to one-third. All FRC beams have the same constitutes materials with hooked-end steel fiber volume fraction equals 1%. The FGC beams are composed of three equal layers, i.e., FRC in the bottom layer at the tension side, normal strength concrete (NSC) at the middle layer, and high strength concrete at the upper layer in the compression side. The results showed that the predicted values of KIC obtained from ETPFM are considered logic according to the maximum size of the non-damaged defect concept. The crack mouth opening displacement estimated from ETPFM showed acceptable values close to the present experimental results. The KIC values calculated within the presence of fibers in front of and through the MC for FRC beam specimens having 1% SFs is more than twice the value of NSC
Placenta accreta and emergency cesarean delivery correlates to cervical length and transcervical placental thickness measurement
Background: The study aims to evaluate the effect of cervical length and the transcervical placental thickness measurement at 28-30 weeks gestation in predicting the risk of antepartum haemorrhage (APH) and emergency preterm caesarean delivery (CD) in women with placenta previa accreta.Methods: A prospective cohort study conducted at Aswan university hospital from June 2015 to April 2017 included one hundred and five cases diagnosed as placenta previa accreta by transvaginal ultrasound (TVS) between 28-30 weeks gestation were divided into three groups according to their cervical length which measured by TVS: group I (cervical length >30 mm), group II (cervical length 20-30 mm) and group III (cervical length <20 mm). Also, placental thickness measurement was done. Cervical length and placental thickness and correlated with the clinical outcome regarding to gestational age at delivery, APH, emergency CD due to massive haemorrhage, the need for blood transfusion and caesarean hysterectomy.Results: APH and emergency CD due to massive bleeding were significantly higher in cases with short cervical length and thick placenta. APH occurred in 6 cases (15%) in group I, 14 cases (40%) in group II and 24 cases (80%) in group III, (p=0.0001). Emergency CD in group I was performed in 5 cases (12.5 %), 12 cases (34.3 %) in group II and 24 cases (80%) in group III, (p =0.0001). The incidence of APH was higher in thick placenta [6 cases (42.9 %) compared to none with thin placenta in group I (p=0.001), 13 cases (68.4%) compared to one case (6.2%) in group II (p=0.0001) and 21 cases (100%) compared to 3 cases (33.3%) in group III (p=0.0001)].Conclusions: Short cervical length and increased placental thickness may predict the risk of APH and emergency preterm CD in patients with placenta accreta
Cataract Surgery Outcomes in Retinitis Pigmentosa A Comparative Clinical Database Study
PURPOSE: To report visual acuity (VA) outcomes, intraoperative and postoperative complications of isolated cataract surgery in eyes with retinitis pigmentosa (RP), compared with non-RP-affected eyes. DESIGN: Retrospective clinical cohort study. METHODS: A total of 113,389 eyes underwent cataract surgery between December 2010 and December 2014 at 8 clinical sites in the United Kingdom. Eyes with RP as the only comorbid pathology and eyes without any ocular comorbidities (controls) undergoing cataract surgery were compared. VA at 4-12 weeks postoperatively and rates of intraoperative and postoperative complications are reported. RESULTS: Seventy-two eyes had RP. The mean age in the RP group was 57±15 compared to 75±10 in controls (p<0.001). Females represented 46% of RP cases and 60% of controls (p=0.06). Preoperative VA (mean LogMAR = 1.03 vs 0.59, p<0.001) and postoperative VA (0.71 vs 0.14, p<0.001) were worse in RP. The mean VA gain was 0.25±0.60 LogMAR in RP vs 0.43±0.48 LogMAR in controls (p<0.001). There were no significant differences in the rate of intraoperative pupil expansion use, posterior capsular tears, or zonular dialysis. Postoperative cystoid macular edema developed in 6.9% of RP eyes and 1% of controls (p<0.001). The need for IOL repositioning or exchange was not statistically different between the two groups. CONCLUSION: Cataract surgery can improve vision in eyes with RP and cataract. Intraoperative complications were similar to control eyes; however, RP eyes experienced more frequent postoperative cystoid macular edema
GWAS: Fast-forwarding gene identification and characterization in temperate Cereals: lessons from Barley – A review
Understanding the genetic complexity of traits is an important objective of small grain temperate cereals yield and adaptation improvements. Bi-parental quantitative trait loci (QTL) linkage mapping is a pow- erful method to identify genetic regions that co-segregate in the trait of interest within the research pop- ulation. However, recently, association or linkage disequilibrium (LD) mapping using a genome-wide association study (GWAS) became an approach for unraveling the molecular genetic basis underlying the natural phenotypic variation. Many causative allele(s)/loci have been identified using the power of this approach which had not been detected in QTL mapping populations. In barley (Hordeum vulgare L.), GWAS has been successfully applied to define the causative allele(s)/loci which can be used in the breeding crop for adaptation and yield improvement. This promising approach represents a tremendous step forward in genetic analysis and undoubtedly proved it is a valuable tool in the identification of can- didate genes. In this review, we describe the recently used approach for genetic analyses (linkage map- ping or association mapping), and then provide the basic genetic and statistical concepts of GWAS, and subsequently highlight the genetic discoveries using GWAS. The review explained how the candidate gene(s) can be detected using state-of-art bioinformatic tools
Optimization, ex vivo permeation, and stability study of lipid nanocarrier loaded gelatin capsules for treatment of intermittent claudication
Pregnancy outcome according to body mass index in primigravidas: a prospective cohort study
Objective: The study aims to evaluate the association between Body Mass Index (BMI), gestational weight gain (GWG) and adverse obstetric outcomes among primigravidas.
Material and methods: This was a prospective cohort study conducted at a tertiary University Hospital between June 2015 and May 2017. The study included 480 primigravidas, with singleton pregnancies, who were divided into three groups: women with a healthy weight (BMI: 18.5–24.9 kg/m2) overweight (BMI: 25 – 29.9 kg/m2) and obese (BMI ≥ 30 kg/m2). The primary outcome of the study was the rate of GWG in the participants. Secondary outcomes included the rate of gestational diabetes mellitus (GDM), gestational hypertension, pre-eclampsia, preterm labor (PTL), postdate pregnancy, fetal macrosomia and the rate of birth by cesarean (CB).
Results: There were no significant differences between groups regarding the socio-demographic criteria. The rate of GWG was significantly higher in obese women versus average weight women (11.4±1.73 vs. 10.49±1.09, p=0.0001). There was an increased incidence of GDM (p=0.008), gestational hypertension (p=0.001), pre-eclampsia (p=0.0001), PTL (p=0.002), postdate (p=0.0001) and macrosomia (p=0.0001) in women who were obese compared with women with a healthy weight. Additionally, there was an increased incidence of CB with increasing body mass (p=0.0001)
Conclusions: Higher BMI in primigravidas is associated with increased GWG and with adverse pregnancy outcomes such as GDM, gestational hypertension, pre-eclampsia, PTL, postdate, fetal macrosomia and cesarean birth
Assessment of wave energy location, technology, and converter toward sustainability using integrated spherical fuzzy MCDM approach
Due to climate change, fossil fuel reduction, growing energy usage, and ecological impacts, the need for renewable energy sources is rising quickly. A large amount of energy comes from the ocean through the tide; renewable energy must be exploited. One important energy source is wave energy converters (WECs), which enhance efficiency and grow energy. This study presented a case study from three layers of the Red Sea in Egypt for selecting optimal wave energy location (WEL), wave energy technology (WET), and WEC. The spherical fuzzy set (SFS) framework deals with uncertainty and vague information in this selection process. The SFS is integrated with multi-criteria decision-making (MCDM) to deal with various criteria in each layer. This study uses two MCDM methods under the SFS environment: The Stepwise Weighted Assessment Ratio Analysis (SWARA) method and the Weighted Euclidean Distance Based Approach (WEDBA) method. The SF-SWARA method is used to compute the criteria weights in each layer. Then, the SF-WEDBA method ranks the alternatives in each layer. The main results in each layer show that the accessibility criterion, Economic factors, and energy production criterion have the highest weight in the three layers. Sensitivity analysis and comparative analysis are conducted in each layer.publishedVersio
Intrapapillary vessel density using optical coherence tomography angiography in primary open-angle glaucoma and normal eyes
Background: Optical coherence tomography angiography (OCTA) is used to quantify optic nerve blood flow in patients with primary open-angle glaucoma (POAG). Intrapapillary vessel density (iVD) has a high diagnostic accuracy for differentiating healthy from glaucomatous eyes. We compared the iVD of patients with POAG with that of healthy controls in an Egyptian tertiary referral center.
Methods: This cross-sectional study consecutively recruited patients with medically controlled POAG and age- and sex-matched healthy individuals. All study participants underwent a detailed medical history evaluation and comprehensive ophthalmic examination, with recording of the cup-to-disc ratio (C/D ratio) and intraocular pressure (IOP). Humphrey visual field evaluation using the standard 24-2 program was performed and global indices, including mean deviation (MD) and pattern standard deviation (PSD), were extracted. OCTA and spectral-domain (SD) OCT images were obtained. Average thickness of the retinal nerve fiber layer (RNFL) and thicknesses in the superior, inferior, nasal, and temporal quadrants were recorded. OCTA imaging was used to measure vessel density, and the automatically processed data for iVD were extracted.
Results: We included 86 eyes, 43 in the POAG and 43 in the healthy control group, with male predominance in both groups and mean (standard deviation [SD]) ages of 42.1 (9.4) and 39.3 (9.6) years, respectively. The two groups were comparable in terms of mean age, sex ratio, laterality of the included eyes, and mean IOP (all P > 0.05). The mean (SD) C/D ratio, MD, and PSD were significantly higher in the POAG group than in the control group (all P < 0.01). The mean (SD) average RNFL thickness and RNFL thicknesses in the four quadrants were significantly less in glaucomatous eyes than in healthy control eyes (all P < 0.05). Eyes with POAG had a significantly lower mean (SD) iVD than healthy control eyes (P < 0.01). Linear regression analysis revealed a significant positive correlation between iVD and average RNFL thickness (r = + 0.52; P < 0.001) and a significant negative correlation between iVD and PSD (r = - 0.31; P = 0.042) in eyes with POAG.
Conclusions: The structural, vascular, and functional parameters measured in this study deteriorated in eyes with POAG compared to controls. Significant circumpapillary RNFL thinning correlated well with reduced iVD in eyes with POAG. Similarly, a lower iVD detected using OCTA had a significant inverse correlation with PSD in the perimetry of eyes with POAG. Further studies with additional parameters and longer follow-up periods are required to verify our preliminary findings
The effect of regular daily walking on adverse pregnancy outcomes among overweight primigravidas: a prospective cohort study
Objective: The study aims to evaluate the effect of regular daily walking on the occurrence of adverse pregnancy outcomes among overweight primigravidas.
Materials and Methods: A prospective cohort study conducted at Aswan University Hospital from March 2015 to December 2016. The study included 360 overweight primigravidas, with singleton pregnancies, who were divided into two groups: Group I (control group) and Group II (study group) under supervised regular walking 5 times per week for 30 minutes, starting from 10-12 weeks of gestational age to 38-39 weeks of gestational age. The primary outcome of the study was the rate of gestational weight gain in participants in both groups. Secondary outcomes included the rate of gestational diabetes mellitus, gestational hypertension, preeclampsia, preterm labor ( 4 kg), excessive maternal weight gain (>11.5 kg), and the rate of cesarean delivery.
Results: There were no significant differences between groups with regard to the basic criteria. The exercise program decreased the incidence of preeclampsia (OR=0.120; 95% CI=0.015-0.970; p=0.037), postdate (OR=0.274; 95% CI= 0.099-0.759); p=0.008), excessive weight gain (OR=0.220; 95% CI=0.114-0.424), p=0.000), and cesarean delivery (OR=0.519; 95% CI=0.316-0.841, p=0.007).
Conclusion: Regular maternal walking throughout the pregnancy may be a preventive tool for preeclampsia, postdate pregnancy, excessive weight gain and may decrease the incidence of cesarean delivery in primigravidas
Detailed genetic analyses highlight genetic variation and genomic regions for lead tolerance in spring wheat
IntroductionUnderstanding the dynamics of Pb tolerance across different growth stages is essential for breeding wheat varieties with comprehensive tolerance to Pb contamination throughout their life cycle. Lead (Pb) in soil affects wheat plants at all growth stages. However, the seedling stage is considered a sensitive growth stage for the tolerance of most abiotic stresses. Genetic variation in lead tolerance is poorly understood, and genetic control has still not been investigated.MaterialsIn this study, 103 highly diverse wheat genotypes were investigated under normal and lead stress conditions at the seedling stage. Different seedling growth traits were scored under each treatment. GWAS was performed via two different sets of markers: 21,750 (25K Infinium iSelect array) and 37,790 SNPs (genotyping-by-sequencing) to identify SNP markers associated with the studied seedling traits.ResultsHigh genetic variation was found among all the genotypes for all the traits. High broad-sense heritability estimates ranging from 0.25-0.93 were observed. A highly significant correlation was found among all the traits scored under normal and lead stress conditions. Low or no significant phenotypic correlations were found for lead tolerance between the seedling and adult growth stages. A set of eight genotypes were classified as lead-tolerant genotypes. The GWAS revealed a set of 222 significant markers associated with lead tolerance. Markers with pleiotropic effects were detected under Pb stress and between lead and normal conditions. Interestingly, five significant markers were found to be associated with lead tolerance at the seedling and adult growth stages.DiscussionThe results of this study provide new and novel insights into genetic control and genetic variation in lead tolerance at the early growth stage. All the genes and genotypes reported in this study will be very useful for further investigations of lead tolerance in wheat at different growth stages
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