5,292 research outputs found
A methodology for flexibility analysis of pipeline systems
Pipeline systems serve a crucial role in an effective transport of fluids to the designated location for medium to long span of distances. Owing to its paramount economic significance, pipeline design field have undergone extensive development over the past few years for enhancing the optimization and transport efficiency. This research paper attempts to propose a methodology for flexibility analysis of pipeline systems through employing contemporary computational tools and practices. A methodical procedure is developed, which involves modeling of the selected pipeline system in CAESAR II followed by the insertion of pipe supports and restraints. The specific location and selection of the inserted supports is based on the results derived from the displacement, stress, reaction, and nozzle analysis of the concerned pipeline system. Emphasis is laid on the compliance of the design features to the leading code of pipeline transportation systems for liquid and slurries, ASME B31.4. The discussed procedure and approach can be successfully adjusted for the analysis of various other types of pipeline system configuration. In addition to the provision of systematic flow in analysis, the method also improves efficient time-saving practices in the pipeline stress analysis
Percutaneous Mitral Valve Repair versus Optimal Medical Therapy in Patients with Functional Mitral Regurgitation: A Systematic Review and Meta-Analysis
Objectives. To compare percutaneous mitral valve repair (PMVR) with optimal medical therapy (OMT) in patients with heart failure (HF) and severe functional mitral regurgitation (FMR). Background. Many patients with HF and FMR are not suitable for surgical valve replacement and remain symptomatic despite maximal OMT. PMVR has recently emerged as an alternative solution. Methods. We performed a systematic review and a meta-analysis to address this question. Cochrane CENTRAL, MEDLINE, and Scopus were searched for randomized (RCT) and nonrandomized studies comparing PMVR with OMT in patients with HF and FMR. Primary endpoint was all-cause midterm mortality (at 1 and 2 years). Secondary endpoints were 30-day mortality and cardiovascular mortality and HF hospitalizations, at maximum follow-up. Studies including mixed cohort of degenerative and functional MR were allowed initially but were excluded in a secondary sensitivity analysis for each of the study’s end points. This meta-analysis was performed following the publication of two RCTs (MITRA-FR and COAPT). Results. Eight studies (six observational, two RCTs) comprising 3,009 patients were included in the meta-analysis. In comparison with OMT, PMVR significantly reduced 1-year mortality (RR: 0.70 [0.56, 0.87]; p=0.002; I2=47.6%), 2-year mortality (RR: 0.63 [0.55, 0.73]; p\u3c0.001; I2=0%), and cardiovascular mortality (RR: 0.32 [0.23, 0.44]; p\u3c0.001; I2=0%). No significant difference between PMVR+OMT and OMT was noted in HF hospitalization (HR: 0.69 [0.40, 1.20]; p=0.19; I2=85%) and 30-day mortality (RR: 1.13 [0.68, 1.87]; p=0.16; I2=0%). Conclusions. In comparison with OMT, PMVR significantly reduces 1-year mortality, 2-year mortality, and cardiovascular mortality in patients with HF and severe MR
Učinak duljine skladištenja na kvalitetu jaja i valivost kokoši Rhode Island Red.
In this research study, hatchability results and some internal egg quality characteristics of 0, 2, 3, 5, 7 and 9 d stored eggs in RIR were examined. It was determined that the effect of storage time on hatchability, hatchability of fertile eggs, embryonic mortality, chick weight, albumen weight, yolk weight, albumen index, yolk index and Haugh unit was significant (P<0.05). There was no positive or negative effect of storage time on the fertility rates, but there was a negative effect of storage time on egg weight, hatchability, embryonic development and chick weight on d 3 (P<0.05). It was determined that prolonged storage time caused a decrease in the albumen weight, yolk weight, albumen index, yolk index and Haugh unit value of Rhode Island Red eggs. Rhode Island Red eggs should not be stored more than 3 d.U radu su istraženi valivost i karakteristike jaja pasmine Rhode Island Red u uvjetima različite duljine skladištenja od 0, 2, 3, 5, 7 i 9 dana. Duljina skladištenja statistički je značajno (P<0,05) utjecala na valivost, valivost oplođenih jaja, smrtnost embrija, masu pilića, masu bjelanjka, masu žumanjka, indeks bjelanjka, indeks žumanjka te na vrijednost Haughove jedinice. Nije utvrđen ni pozitivan ni negativan učinak duljine skladištenja na stopu plodnosti, ali je duljina skladištenja od 3 dana značajno utjecala (P<0,05) na masu jaja, valivost, razvoj embrija i masu pilića. Ustanovljeno je da u jaja Rhode Island Red kokoši produženo vrijeme skladištenja dovodi do smanjenja mase bjelanjka, mase žumanjka, indeksa bjelanjka, indeksa žumanjka i vrijednost Haughove jedinice. Zaključeno je da jaja kokoši Rhode Island Red ne bi trebalo skladištiti dulje od 3 dana
Infrared Nonlinear Optics
Contains reports on one research project.U.S. Air Force - Office of Scientific Research (Grant AFOSR-76-2894
Predicting the effect of voids on mechanical properties of woven composites.
An accurate yet easy to use methodology for determining the effective mechanical properties of woven fabric reinforced composites is presented. The approach involves generating a representative unit cell geometry based on randomly selected 2D orthogonal slices from a 3D X-ray micro-tomographic scan. Thereafter, the finite element mesh is generated from this geometry. Analytical and statistical micromechanics equations are then used to calculate effective input material properties for the yarn and resin regions within the FE mesh. These analytical expressions account for the effect of resin volume fraction within the yarn (due to infiltration during curing) as well as the presence of voids within the composite. The unit cell model is then used to evaluate the effective properties of the composite.DelPHE 780 Project funded by UK Department of International Development (DFID), through British Council managed DelPHE scheme
Functional quality of optimized peach‐based beverage developed by application of ultrasonic processing
The influence of thermal treatment (at 90°C for 10 min) and sonication (at 20 kHz and 130 W for 30, 60, and 90 min on room temperature) on the physicochemical properties, bioactive compounds, antioxidant activity, and organic acids of fresh formulated functional peach beverage was investigated. The results indicated that conventional pasteurization and sonication treatment did not show any significant changes in pH value and Brix amount of juice, and however, a rise in cloud value was observed under all processing conditions. The thermal treatment caused the decrement in total phenolic content (TPC), total flavonoid content (TFC), antioxidant activity (assessed by diphenyl dipicryl hydrazyl (DPPH), ferric ion reducing antioxidant power (FRAP) and 2,2'‐azino‐bis(3‐ethylbenzothiazoline‐6‐sulfonic acid) (ABTS)), and organic acids of juice, whereas sonication treatment for 90 min increased maximum the activity of bioactive compounds (TPC: 600.61 µg/100 ml; TFC: 177 µg CE/100 ml), antioxidants (DPPH: 51.87%; FRAP: 506.13 µmol Trolox/L; ABTS: 1,507.375 µmol Trolox/L), and organic acids (malic acid: 998; citric acid: 128; oxalic acid: 145; shikimic acid: 63 µg/100 ml) as compared to other treatment conditions and control. Multivariate data analysis was done by principal component analysis as it identifies patterns in data by comparing data sets which is further expressed based on their similarities and discriminations, respectively
A new diagnostic algorithm for assessment of patients with single ventricle before a Fontan operation
ObjectivesCardiac catheterization has a low diagnostic yield before a Fontan operation, and magnetic resonance imaging and computed tomography are reliable alternatives to invasive angiography. A new diagnostic algorithm to avoid cardiac catheterization in “low-risk” subjects before a Fontan operation is proposed.MethodsThe proposed algorithm would identify “high-risk” subjects on the basis of risk factors on medical history, echocardiography, and noninvasive angiography. The efficacy of this algorithm in screening for subjects deemed to be inoperable after catheterization was evaluated retrospectively in 151 children. For this analysis, results of conventional angiography (assumed to be equivalent to noninvasive angiography) were used.ResultsAccording to the algorithm, 95 (63%) of 151 subjects had no risk factors (“low risk”) whereas 56 (37%) of 151 had 1 risk factor or more (“high risk”). Nine (6%) of 151 subjects were found to be inoperable after catheterization and all 9 were correctly classified as high risk by the algorithm. In the 135 of 151 subjects who underwent a Fontan operation, the algorithm predicted an adverse postoperative outcome with a sensitivity of 51% and specificity of 78%. However, this prediction was not improved by including elevated pulmonary artery pressure or ventricular filling pressure as additional risk factors.ConclusionsThe proposed algorithm effectively screened for subjects who were deemed unsuitable for a Fontan procedure. In addition, omitting preoperative invasive hemodynamic assessment did not impair prediction of adverse postoperative outcomes. Prospective evaluation of such a noninvasive diagnostic strategy before the Fontan operation is warranted
Theoretical and experimental analysis of multifunctional high performance cement mortar matrices reinforced with varying lengths of carbon fibers
An effective scheme to formulate high performance and multifunctional cement based mortar composites reinforced with varying lengths of carbon fibers has been devised. The detailed investigations pertaining to the fracture response of composites in cracks initiation and progression phases, their conducting mechanism and volumetric stability were performed with varying loads of 6mm and 12mm long carbon fibers at two different w/c ratios i.e. 0.45 and 0.50. The experiments concluded that an optimum addition of carbon fibers results in substantial improvement of fracture properties alongside significant reduction in electrical resistivity and total plastic shrinkage. The field emission scanning electron microscopy of the cryofractured specimen revealed crack arresting actions of uniformly distributed carbon fibers through successful crack bridging and branching phenomenon
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Whole genome sequencing data of multiple individuals of Pakistani descent
Here we report whole genome sequencing of four individuals (H3, H4, H5, and H6) from a family of Pakistani descent. Whole genome sequencing yielded 1084.92, 894.73, 1068.62, and 1005.77 million mapped reads corresponding to 162.73, 134.21, 160.29, and 150.86 Gb sequence data and 52.49x, 43.29x, 51.70x, and 48.66x average coverage for H3, H4, H5, and H6, respectively. We identified 3,529,659, 3,478,495, 3,407,895, and 3,426,862 variants in the genomes of H3, H4, H5, and H6, respectively, including 1,668,024 variants common in the four genomes. Further, we identified 42,422, 39,824, 28,599, and 35,206 novel variants in the genomes of H3, H4, H5, and H6, respectively. A major fraction of the variants identified in the four genomes reside within the intergenic regions of the genome. Single nucleotide polymorphism (SNP) genotype based comparative analysis with ethnic populations of 1000 Genomes database linked the ancestry of all four genomes with the South Asian populations, which was further supported by mitochondria based haplogroup analysis. In conclusion, we report whole genome sequencing of four individuals of Pakistani descent
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