Determining the endurance limit of AISI 4340 steels in terms of different statistical approaches

In engineering applications, fatigue phenomenon is a key issue and needs to be analyzed in the beginning of design phase in case of any component exposed to alternating loading on operation otherwise catastrophic fatigue failure may cause. Component can be designed with safe life, fail-safe, and damage tolerant approach based on whether redundant load path and damage sensitive. Before starting analyzing the structure, material allowable data needs to be presented in a reliable way to predict fatigue life of components. SN curves with presented confidence levels are the robust approach to make a prediction on safe life of a structure in terms of fatigue. In this point, there are so many approaches to determine fatigue limit of materials and issue shall be handled by statistical manner. In literature, different staircase and curve fitting methods were presented to estimate endurance limit of materials and some reliability manuscript published. In this paper, fatigue limit of AISI 4340 steel will be investigated through most convinced staircase and curve fitting approaches and their reliability will be queried

Advanced Nanostructured Electrodes for Solar Fuel Conversion

Photoelectrochemical (PEC) water splitting and electrochemical hydrogen evolution reaction (HER) appear to be key technological components of a hydrogen-based economy which may secure sustainable energy future. Nevertheless, several limitations of PEC cell and HER electrode materials is still present. Modification of semiconductor materials bearing narrow band gap for visible spectrum, high solar to hydrogen conversion efficiency and high stability for efficient PEC cell is required for futures commercially applicable energy conversion systems. Besides, development of cost effective non-noble metal electrocatalysts with remarkable electrocatalytic efficiency for HER to overcome the limitations of high cost noble platinum (Pt)-group materials, is necessary en route to profitable and efficient water splitting devices. Thereupon, firstly we employed plasmonic nanoparticles combined with semiconductor to confine light absorption locally in active layer of semiconductor. These nanophotonic structures can generate surface plasmon resonances (SPR) which will act light antennas and localize electromagnetic radiation energy near the active surface layer. Accordingly, core@shell and core@shell@shell nanoparticles were implemented to modify PEC performance of BiVO4 photoanode. In this regard, the heterostructure offered improved light absorption, higher catalytic efficiency and efficient separation and transport of photogenerated charge carriers leading to improved PEC cell efficiency. Furthermore, metal chalcogenide sensitized SnO2 nanowire based heteronanostructured systems tested as an active photoanode material for PEC cell. Highly conductive SnO2 nanowire arrays has been fabricated and different sensitization methods has been used on these photoelectrodes. The novel photoelectrode exhibits panchromatic light absorption capability, low thermalization loss, and improved photogenerated charge carrier transport behavior, providing improved photocurrent density PEC cell system. Lastly, Mo2C and Mo2C-GO electrocatalysts have been fabricated using in situ growth, microwave assisted, facile preparation method. Electrocatalytic activities were studied as a cathode for HER. Mo2C-GO nanocomposites provide enhanced electronic conductivity, reduced particle size, more electrocatalytic active sites, improved structural stability. Hence, molybdenum-based electrocatalysts are promising non-noble, cost-effective, conductive, catalytically active alternatives to noble Pt group electrocatalysts. Overall, this dissertation study provides a detailed study to shed light into the rational design of advanced nanostructured PEC photoanodes and HER catalysts, and systematic study of synthesis, characterization, photoelectrochemical and electrochemical activities of the resultant photoanodes and cathodes

Morbidly adherent placenta and cesarean section methods. A retrospective comparative multicentric study on two different skin and uterine incision

Objectives: Morbidly adherent placenta (MAP) is one of leading causes of maternal mortality, with an increasing rate because of repeated cesarean sections (CS). The primary objective of this study is to compare two techniques of skin and uterine incisions in patients with MAP, evaluating the maternal fetal impact of the two methods. Retrospective multicentric cohort study.Material and methods: A total of 116 women with MAP diagnosis were enrolled and divided in two groups. Group one, comprised of 81 patients, abdominal entry was performed by Pfannenstiel skin incision plus an upper transverse lower uterine segment (LUS) incision (transverse-transverse), which was 2–3 cm above the MAP border, with the uterus in the abdomen. In group two, comprised of 35 patients, abdominal entry was performed by an infra-umbilical midline abdominal incision, by vertical-vertical technique, and the pregnant uterus was incised by a midline incision (vertical) from the fundus till the border of the MAP. Total surgery time, blood loss, blood product consumption, total hospital stay, cosmetic outcomes, and postoperative complications were investigated.Results: Total time of surgery was significantly shorter in group 1 (p < 0.05). Intraoperative blood loss was higher in group 2. Difference between preoperative and postoperative Hb and Htc levels were 3.30 ± 1.04 and 12.99 ± 5.07 respectively (p = 0.012; p = 0.033). The use of erythrocyte suspension (ES), fresh frozen plasma (FFP), and cryoprecipitate and thrombocyte suspension (TS) were found to be significantly lower in patients of group 1than vertical-vertical group (p = 0.008, p = 0.009, p = 0.001, p = 0.001, respectively). There was no difference in terms of total length of hospital stay between groups.Conclusions: In a subgroup of patients diagnosed for MAP, the transverse-transverse incision resulted in less bleeding, less blood and blood product use, and had better cosmetic results than vertical-vertical incision. Moreover, the total time of surgery, crucial for MAP patients, seems to be shorter also in transverse-transverse incision than in vertical-vertical incision

Brief Report: Deficiency of Complement 1r Subcomponent in Early-Onset Systemic Lupus Erythematosus: The Role of Disease-Modifying Alleles in a Monogenic Disease

Objective: To identify a genetic cause of early-onset systemic lupus erythematosus (SLE) in a large consanguineous family from Turkey and to study the mechanisms of the disease. Methods: We performed whole-exome sequencing and single-nucleotide polymorphism array genotyping in family members with and without SLE. Protein and gene expression, cytokine profile, neutrophil extracellular trap (NET) formation, and presence of low-density granulocytes were evaluated in patient primary cells and serum samples. Results: We identified a novel, homozygous, loss-of-function mutation (p.Pro445Leufs*11) in the C1R gene. Using the Sanger method of DNA sequencing in 14 family members, we confirmed the presence of the mutation in 4 patients with SLE and in an asymptomatic 9-year-old girl. Complement levels were low in sera from patients with truncated C1r protein. Two siblings with SLE who were available for detailed evaluation exhibited strong type I interferon (IFN) inflammatory signatures despite their disease being clinically inactive at the time of sampling. The type I IFN transcriptional signature in the patients’ blood correlated with disease expressivity, whereas the neutrophil signature in peripheral blood mononuclear cells was likely associated with disease severity. The female patient with SLE with the most severe phenotype presented with a stronger neutrophil signature, defined by enhanced NET formation and the presence of low-density granulocytes. Analysis of exome data for modifying alleles suggested enrichment of common SLE-associated variants in the more severely affected patients. Lupus-associated HLA alleles or HLA haplotypes were not shared among the 4 affected subjects. Conclusion: Our findings revealed a novel high-penetrance mutation in C1R as the cause of monogenic SLE. Disease expressivity in this family appears to be influenced by additional common and rare genetic variants

CDH12 as a Candidate Gene for Kidney Injury in Posterior Urethral Valve Cases:A Genome-wide Association Study Among Patients with Obstructive Uropathies

Background: Posterior urethral valves (PUVs) and ureteropelvic junction obstruction (UPJO) are congenital obstructive uropathies that may impair kidney development. Objective: To identify genetic variants associated with kidney injury in patients with obstructive uropathy. Design, setting, and participants: We included 487 patients born in 1981 or later who underwent pyeloplasty or valve resection before 18 yr of age in the discovery phase, 102 PUV patients in a first replication phase, and 102 in a second replication phase

Magnetic resonance imaging based kidney volume assessment for risk stratification in pediatric autosomal dominant polycystic kidney disease

IntroductionIn the pediatric context, most children with autosomal dominant polycystic kidney disease (ADPKD) maintain a normal glomerular filtration rate (GFR) despite underlying structural kidney damage, highlighting the critical need for early intervention and predictive markers. Due to the inverse relationship between kidney volume and kidney function, risk assessments have been presented on the basis of kidney volume. The aim of this study was to use magnetic resonance imaging (MRI)-based kidney volume assessment for risk stratification in pediatric ADPKD and to investigate clinical and genetic differences among risk groups.MethodsThis multicenter, cross-sectional, and case-control study included 75 genetically confirmed pediatric ADPKD patients (5–18 years) and 27 controls. Kidney function was assessed by eGFR calculated from serum creatinine and cystatin C using the CKiD-U25 equation. Blood pressure was assessed by both office and 24-hour ambulatory measurements. Kidney volume was calculated from MRI using the stereological method. Total kidney volume was adjusted for the height (htTKV). Patients were stratified from A to E classes according to the Leuven Imaging Classification (LIC) using MRI-derived htTKV.ResultsMedian (Q1-Q3) age of the patients was 6.0 (2.0–10.0) years, 56% were male. There were no differences in sex, age, height-SDS, or GFR between the patient and control groups. Of the patients, 89% had PKD1 and 11% had PKD2 mutations. Non-missense mutations were 73% in PKD1 and 75% in PKD2. Twenty patients (27%) had hypertension based on ABPM. Median htTKV of the patients was significantly higher than controls (141 vs. 117 ml/m, p = 0.0003). LIC stratification revealed Classes A (38.7%), B (28%), C (24%), and D + E (9.3%). All children in class D + E and 94% in class C had PKD1 variants. Class D + E patients had significantly higher blood pressure values and hypertension compared to other classes (p > 0.05 for all).DiscussionThis study distinguishes itself by using MRI-based measurements of kidney volume to stratify pediatric ADPKD patients into specific risk groups. It is important to note that PKD1 mutation and elevated blood pressure were higher in the high-risk groups stratified by age and kidney volume. Our results need to be confirmed in further studies

Clinical approach for the classification of congenital uterine malformations

A more objective, accurate and non-invasive estimation of uterine morphology is nowadays feasible based on the use of modern imaging techniques. The validity of the current classification systems in effective categorization of the female genital malformations has been already challenged. A new clinical approach for the classification of uterine anomalies is proposed. Deviation from normal uterine anatomy is the basic characteristic used in analogy to the American Fertility Society classification. The embryological origin of the anomalies is used as a secondary parameter. Uterine anomalies are classified into the following classes: 0, normal uterus; I, dysmorphic uterus; II, septate uterus (absorption defect); III, dysfused uterus (fusion defect); IV, unilateral formed uterus (formation defect); V, aplastic or dysplastic uterus (formation defect); VI, for still unclassified cases. A subdivision of these main classes to further anatomical varieties with clinical significance is also presented. The new proposal has been designed taking into account the experience gained from the use of the currently available classification systems and intending to be as simple as possible, clear enough and accurate as well as open for further development. This proposal could be used as a starting point for a working group of experts in the field

Tubular functions in familial Mediterranean fever

In this study, we aimed to evaluate renal tubular function in familial Mediterranean fever (FMF). Urinary N-acetyl-beta-D glucosaminidase (U-NAG, beta(2)-microglobulin (U-beta(2)M) and microalbumin (Ua) levels were measured in children with different clinical stages of FMF (58 patients with FMF, 9 patients with amyloidosis secondary to (FMF). Control groups were healthy children (n=21), children with upper respiratory tract infection (URTI) (n=21) and with steroid sensitive nephrotic syndrome (SSNS) (n=18). U-NAG was significantly increased in patients with a recent diagnosis of FMF compared to patients with FMF on colchicine and to healthy controls. in patients with recently diagnosed FMF, a marked decrease in U-NAG, U-beta(2)M and Ua were determined after three months on colchicine therapy. On the other hand, U-NAG and Ubeta(2)M levels were increased in patients with FMF during attacks and then decreased in the post-attack period. U-beta(2)M in patients with FMF during attacks was significantly different from patients with URTI. Finally, U-NAG and U-beta(2)M were increased significantly in patients with FMF-amyloidosis and SSNS when compared with other FMF groups and healthy controls, respectively. In conclusion, the high U-NAG value in newly diagnosed patients compared to that of patients taking colchicine and the decline of U-NAG and U-beta(2)M levels after attack to the levels observed in colchicine users (without a significant change in Ua value) suggest that the renal injury early in the course of FMF might be dominantly at the level of the tubuli

Zeolite confined rhodium(0) nanoclusters as highly active, reusable, and long-lived catalyst in the methanolysis of ammonia-borane

Addressed herein is the preparation, characterization and the catalytic use of zeolite confined rhodium(0) nanoclusters in the methanolysis of ammonia-borane. Rhodium(0) nanoclusters; could be generated in zeolite-Y by a two-step procedure: (i) incorporation of rhodium(Ill) cations into the zeolite-Y by ion-exchange and (ii) reduction of rhodium(Ill) ions within the zeolite cages by sodium borohydride in aqueous solution, followed by filtration and dehydration by heating to 550 degrees C under 10(-4) Torr. Zeolite confined rhodium(0) nanoclusters are stable enough to be isolated as solid materials and characterized by ICP-OES, XRD. SEM, EDX, HR-TEM, XPS and N-2 adsorption-desorption technique. The zeolite confined rhodium(0) nanoclusters are isolable, bottleable, redispersible and reusable as an active catalyst in the methanolysis of ammonia-borane even at low temperatures. They provide exceptional catalytic activity with an average value of TOF = 380 h(-1) and unprecedented lifetime with 74,300 turnovers in the methanolysis of ammonia-borane at 25 +/- 0.1 degrees C. The work reported here also includes the full experimental details of the collection of a wealth of previously unavailable kinetic data to determine the rate law, and activation parameters (E-a, Delta H-not equal and Delta S-not equal) for the catalytic methanolysis of ammonia-borane