Experimental study on dynamic pipe fracture in consideration of hydropower plant model

AbstractIn the case of sudden valve closure, water hammer creates the most powerful pressure and damage to pipeline systems. The best way to protect the pipeline system is to eliminate water hammer. The main reasons for water hammer occurrence are valve closure, high initial velocity, and static pressure. However, it is difficult to eliminate water hammer. Water hammer tends to occur when the valve is being closed. In this study, the pipe fracture caused by static water pressure, gradually increasing pressure, and suddenly increasing pressure were compared experimentally in a breaking PVC test pipe. The quasi-static zone, the dynamic zone, and the transition zone are defined through the results of those experiments, with consideration of the fracture patterns of test pipes and impulses. The maximum pressure results were used to design the pipeline even though it is in the dynamic zone

The Variation in the Lumbar Facet Joint Orientation in an Adult Asian Population and Its Relationship with the Cross-Sectional Area of the Multifidus and Erector Spinae

Study DesignCross-sectional study of healthy volunteers.PurposeWe aimed to investigate the variation in the lumbar facet joint orientation in an adult Asian population. The relationship between the facet joint orientation and muscle cross-sectional area (CSA) of multifidus and erector spinae was also clarified.Overview of LiteratureSeveral studies have reported that lumbar pathologies, such as lumbar spondylolysis and degenerative spondylolisthesis, were related to the horizontally shaped lumbar facet joint orientation at the lower lumbar level. However, data regarding variations in the facet joint orientation in asymptomatic subjects have not been well documented.MethodsIn 31 healthy male adult Asian volunteers, the facet joint orientation and CSA of multifidus and erector spinae were measured using magnetic resonance imaging at the L4–5 and L5–S1 levels. Variation in the facet joint orientation was examined using coefficients of variation (CV). Pearson's product-moment coefficient was used to investigate the relationship between the facet joint orientation and CSA of multifidus and erector spinae.ResultsLumbar facet joint orientation had a wider range of variation at L5–S1 (CV=0.30) than at L4–5 (CV=0.18). The L4–5 facet joint orientation had a weak but significant correlation with the CSA of erector spinae (r=0.40; p=0.031). The CSA of the multifidus had no relationship with the facet joint orientation at the L4–5 (r=0.19; p=0.314) and the L5–S1 level (r=0.19; p=0.312).ConclusionsThe lumbar facet joint orientation was found to have a wide variation, particularly at the L5–S1 in the Asian adult population, and the facet joint orientation had a relationship with the CSA of the erector spinae at the L4–5

Evidence of causality of low body mass index on risk of adolescent idiopathic scoliosis: a Mendelian randomization study

IntroductionAdolescent idiopathic scoliosis (AIS) is a disorder with a three-dimensional spinal deformity and is a common disease affecting 1-5% of adolescents. AIS is also known as a complex disease involved in environmental and genetic factors. A relation between AIS and body mass index (BMI) has been epidemiologically and genetically suggested. However, the causal relationship between AIS and BMI remains to be elucidated.Material and methodsMendelian randomization (MR) analysis was performed using summary statistics from genome-wide association studies (GWASs) of AIS (Japanese cohort, 5,327 cases, 73,884 controls; US cohort: 1,468 cases, 20,158 controls) and BMI (Biobank Japan: 173430 individual; meta-analysis of genetic investigation of anthropometric traits and UK Biobank: 806334 individuals; European Children cohort: 39620 individuals; Population Architecture using Genomics and Epidemiology: 49335 individuals). In MR analyses evaluating the effect of BMI on AIS, the association between BMI and AIS summary statistics was evaluated using the inverse-variance weighted (IVW) method, weighted median method, and Egger regression (MR-Egger) methods in Japanese.ResultsSignificant causality of genetically decreased BMI on risk of AIS was estimated: IVW method (Estimate (beta) [SE] = -0.56 [0.16], p = 1.8 × 10-3), weighted median method (beta = -0.56 [0.18], p = 8.5 × 10-3) and MR-Egger method (beta = -1.50 [0.43], p = 4.7 × 10-3), respectively. Consistent results were also observed when using the US AIS summary statistic in three MR methods; however, no significant causality was observed when evaluating the effect of AIS on BMI.ConclusionsOur Mendelian randomization analysis using large studies of AIS and GWAS for BMI summary statistics revealed that genetic variants contributing to low BMI have a causal effect on the onset of AIS. This result was consistent with those of epidemiological studies and would contribute to the early detection of AIS

A randomized controlled trial comparing the effects of dapagliflozin and DPP-4 inhibitors on glucose variability and metabolic parameters in patients with type 2 diabetes mellitus on insulin

Background: Dipeptidyl peptidase-4 (DPP-4) inhibitors and sodium-glucose co-transporter 2 (SGLT2) inhibitors improve hyperglycemia, and the usefulness of co-administration of DPP-4 inhibitors and insulin therapy has been well established. However, it has been still uncertain whether combination therapy of SGLT2 inhibitors and insulin is superior to that of DPP-4 inhibitors and the latter. Therefore, we investigated the superiority of dapagliflozin on glucose fluctuation compared with DPP-4 inhibitors in patients with type 2 diabetes mellitus (T2DM) on insulin using a continuous glucose monitoring (CGM) system. Methods: In this prospective, randomized, open-label controlled trial, 36 patients with T2DM and treated with DPP-4 inhibitors and insulin therapy, were enrolled and allocated into two groups. The patients either switched their DPP-4 inhibitors to dapagliflozin 5 mg for 12 weeks, or continued their DPP-4 inhibitors for the same period. CGM analyses and metabolic markers were assessed before and after treatment periods. Results: In total, data from 29 patients were analyzed. There were no significant differences in the mean amplitude of glycemic excursions and other CGM profiles in either group after treatment. Within the dapagliflozin treatment group, significant reductions of body mass index and albuminuria, and increases of HbA1c, hemoglobin and hematocrit were observed, but improvement of albuminuria was not significant if compared with the DPP-4 continuation group. Conclusions: Combination therapy of dapagliflozin and insulin was not superior in glucose fluctuation to DPP-4 inhibitors on insulin. However, dapagliflozin may in part provide favorable effects on metabolism in patients with T2DM treated with insulin therapy

Ipragliflozin effectively reduced visceral fat in Japanese patients with type 2 diabetes under adequate diet therapy

To investigate if ipragliflozin, a novel sodium-glucose co-transporter 2 inhibitor, alters body composition and to identify variables associated with reductions in visceral adipose tissue in Japanese patients with type 2 diabetes mellitus. This prospective observational study enrolled Japanese participants with type 2 diabetes mellitus. Subjects were administered ipragliflozin (50 mg/day) once daily for 16 weeks. Body composition, visceral adipose tissue volume and plasma variables were measured at 0, 8, and 16-weeks. The subjects' lifestyle habits including diet and exercise were evaluated at baseline and 16 weeks. The primary endpoint was defined as the decrease of visceral adipose tissue mass. Twenty-four of 26 enrolled participants completed the study. The visceral adipose tissue decreased significantly (110 ± 33 to 101 ± 36 cm2, p = 0.005) as well as other parameters for metabolic insufficiency including hemoglobin A1c. Seventy-one % of the total body weight reduction (-2.49 kg) was estimated by a decrease in fat mass (-1.77 kg), and the remaining reduction (22%) by water volume (-0.55 kg). A minor but significant reduction in the skeletal muscle index was also observed. Correlation analyses were performed to identify variables associated with changes in visceral adipose tissue and the only significant variable identified was diet therapy (Spearman's r = -0.416, p = 0.043). Ipragliflozin significantly decreased visceral adipose tissue, and improved parametres for metabolic dysfunction. Adequate diet therapy would be necessary to induce and enhance the therapeutic merit

Coffee consumption and all-cause and cardiovascular mortality: - Three-prefecture cohort in Japan

Junya Sado, Tetsuhisa Kitamura, Yuri Kitamura, Rong Liu, Emiko Ando, Tomotaka Sobue, Yumi Sugawara, Keitaro Matsuo, Tomio Nakayama, Ichiro Tsuji, Hidemi Ito, Takaichiro Suzuki, Kota Katanoda, Suketami Tominaga, Coffee Consumption and All-Cause and Cardiovascular Mortality　― Three-Prefecture Cohort in Japan ―, Circulation Journal, 2019, Volume 83, Issue 4, Pages 757-766, Released March 25, 2019, [Advance publication] Released March 08, 2019, Online ISSN 1347-4820, Print ISSN 1346-9843, https://doi.org/10.1253/circj.CJ-18-0618, https://www.jstage.jst.go.jp/article/circj/83/4/83_CJ-18-0618/_article/-char/e

Complete genome sequences of two highly divergent Japanese isolates of Plantago asiatica mosaic virus

Plantago asiatica mosaic virus (PlAMV) is a member of the genus Potexvirus and has an exceptionally wide host range. It causes severe damage to lilies. Here we report on the complete nucleotide sequences of two new Japanese PlAMV isolates, one from the eudicot weed Viola grypoceras (PlAMV-Vi), and the other from the eudicot shrub Nandina domestica Thunb. (PlAMV-NJ). Their genomes contain five open reading frames (ORFs), which is characteristic of potexviruses. Surprisingly, the isolates showed only 76.0–78.0 % sequence identity with each other and with other PlAMV isolates, including isolates from Japanese lily and American nandina. Amino acid alignments of the replicase coding region encoded by ORF1 showed that the regions between the methyltransferase and helicase domains were less conserved than other regions, with several insertions and/or deletions. Phylogenetic analyses of the full-length nucleotide sequences revealed a moderate correlation between phylogenetic clustering and the original host plants of the PlAMV isolates. This study revealed the presence of two highly divergent PlAMV isolates in Japan