bluuebunny/crossref_metadata_2025 huggingface dataset:
Relation between mean stress, thermodynamic, and lithostatic pressure
Authors: Moulas Evangelos , Schmalholz Stefan M. , Podladchikov Yury , Tajčmanová Lucie , Kostopoulos Dimitrios , Baumgartner Lukas
Published: July 2018

Pressure is one of the most important parameters to be quantified in geological problems. However, in metamorphic systems the pressure is usually calculated with two different approaches. One pressure calculation is based on petrological phase equilibria and this pressure is often termed thermodynamic pressure. The other calculation is based on continuum mechanics, which provides a mean stress that is commonly used to estimate the thermodynamic pressure. Both thermodynamic pressure calculations can be justified by the accuracy and applicability of the results. Here, we consider systems with low‐differential stress (<1 kbar) and no irreversible volumetric deformation, and refer to them as conventional systems. We investigate the relationship between mean stress and thermodynamic pressure. We discuss the meaning of thermodynamic pressure and its calculation for irreversible processes such as viscous deformation and heat conduction, which exhibit entropy production. Moreover, it is demonstrated that the mean stress for incompressible viscous deformation is essentially equal to the mean stress for the corresponding viscous deformation with elastic compressibility, if the characteristic time of deformation is five times longer than the Maxwell viscoelastic relaxation time that is equal to the ratio of shear viscosity to bulk modulus. For typical lithospheric rocks, this Maxwell time is smaller thanc. 10,000 years. Therefore, numerical simulations of long‐term (>10 kyr) geodynamic processes, employing incompressible deformation, provide mean stress values that are close to the mean‐stress value associated with elastic compressibility. Finally, we show that for conventional systems the mean stress is essentially equal to the thermodynamic pressure. However, mean stress and, hence, thermodynamic pressure can be significantly different from the lithostatic pressure.
Warped finite element models predict whole shell failure in turtle shells
Authors: Stayton C. Tristan
Published: July 2018

Finite element (FE) models have become increasingly popular in comparative biomechanical studies, with researchers continually developing methods such as ‘warping’ preexisting models to facilitate analyses. However, few studies have investigated how well FE models can predict biologically crucial whole‐structure performance or whether ‘warped’ models can provide useful information about the mechanical behavior of actual specimens. This study addresses both of these issues through a validation of warped FE models of turtle shells. FE models for 40 turtle specimens were built using 3D landmark coordinates and thin‐plate spline interpolations to warp preexisting turtle shell models. Each actual turtle specimen was loaded to failure, and the load at failure and mode of fracture were then compared with the behavior predicted by the models. Overall, the models performed very well, despite the fact that many simplifying assumptions were made for analysis. Regressions of observed on predicted loads were significant for the dataset as a whole, as well as in separate analyses within two turtle species, and the direction of fracture was generally consistent with the patterns of stresses observed in the models. This was true even when size (an important factor in determining strength) was removed from analyses – the models were also able to predict which shells would be relatively stronger or weaker. Although some residual variation remains unexplained, this study supports the idea that warped FE models run with simplifying assumptions at least can provide useful information for comparative biomechanical studies.
Automatic Enrollment and Its Relation to the Incidence and Distribution of DC Plan Contributions: Evidence from a National Survey of Older Workers
Authors: Butrica Barbara A. , Karamcheva Nadia S.
Published: July 2018

Automatic enrollment has been widely embraced for raising employee participation in 401(k) plans. However, the empirical evidence on the effect of automatic enrollment on plan contributions and retirement saving overall is still imperfect. Using nationally representative data from the Health and Retirement Study (HRS), we find that although automatic enrollment is associated with a higher proportion of workers participating in DC plans, automatically enrolled workers are less likely to contribute to their DC plans and contribute on average less than their voluntarily enrolled counterparts. In contrast, employers of auto‐enrolled workers on average contribute more to their employees' accounts than do the employers of voluntarily enrolled workers. Even so, the combined effect is that the total annual contribution rates of automatically enrolled older workers are 1.6 percentage points lower than those of voluntarily enrolled workers.
Higher parity and risk of metabolic syndrome in Korean postmenopausal women: Korea National Health and Nutrition Examination Survey 2010–2012
Authors: Lee Young , Lee Hae Nam , Kim Sa Jin , Koo Jahyun , Lee Kyung Eun , Shin Jae Eun
Published: July 2018

Aim

We sought to examine whether parity is associated with higher incidence of metabolic syndrome in postmenopausal women.

Methods

We conducted a cross‐sectional study on 4098 Korean postmenopausal women by using nationally representative data from the Korea National Health and Nutrition Examination Survey 2010–2012. Multivariate logistic regression was performed to evaluate the relationship between parity and metabolic syndrome, with adjustment for potential confounding variables.

Results

The rate of metabolic syndrome was significantly higher with increasing number of parity, with dose–response relationship in univariate analysis (P <0.001). In addition, higher parity (≥3 live births) was associated with more prevalence of all components of metabolic syndrome compared with two live births (parity 2 vs 3 vs ≥4: 5.5 vs 12.1 and 14.4%, respectively; P < 0.001). However, after adjusting for demographic, socioeconomic, lifestyle and reproductive factors, we found that only higher parity was significantly associated with metabolic syndrome compared with two live births, and failed to show a dose‐dependent relationship (parity 2 vs 3 vs ≥4: odds ratio 1 vs 1.404 vs 1.379, respectively; P = 0.043). We also proved that among the components of metabolic syndrome, only waist circumference had a significant positive relationship with parity in a multivariable adjusted model (parity 2 vs 3 vs ≥4: odds ratio 1 vs 1.559 vs 1.656, respectively; P < 0.001).

Conclusion

Higher parity was independently associated with a higher risk of metabolic syndrome in postmenopausal women.
Exome sequencing identifies novel ACE splice‐site variant in a fetus with renal tubular dysgenesis
Authors: Das Bhowmik Aneek , Dalal Ashwin , Tandon Ashwani , Aggarwal Shagun
Published: July 2018

We report a 32‐week fetus conceived of consanguineous parentage which presented with severe early onset oligohydramnios and history of a similarly affected sibling in previous pregnancy. Ultrasonography and autopsy were inconclusive, prompting exome sequencing on fetal DNA. This resulted in identification of a homozygous novel 3′ splice‐site variation in intron 17 of the ACE gene (NM_000789.3:c.2642‐1G>A), confirming diagnosis of autosomal recessive renal tubular dysgenesis, and facilitating prenatal diagnosis in subsequent pregnancy.
Quantitative polymerase chain reaction‐based detection of HPV 16 E6 and E7 DNA in oral squamous cell carcinoma
Authors: Thammaiah Smitha , Venkobarao Mohan C. , Sathyavanthan Hemavathy , Mirnalini Angeline S.
Published: July 2018

Background

Although human papillomavirus (HPV) is considered as a causative factor in oral squamous cell carcinoma (OSCCs), its pathogenetic role is not well established. Moreover, a limited number of studies have compared the techniques of detecting the HPV infection in OSCC. This study aimed at the detection of HPV 16 E6 and E7 DNA in OSCC by quantitative polymerase chain reaction (qPCR) technique.

Methodology

This retrospective study included 297 tissue sections obtained from histopathologically confirmed OSCC patients. The classification of tumors as poorly differentiated, moderately differentiated and well differentiated was performed by H&E staining following the WHO criteria for OSCC. The presence of HPV infection was detected by p16INK4A expression, conventional PCR technique, HPV 16 E6, and E7 by qPCR and flow cytometry. All statistical analysis was performed using MedCalc software v.16.4.3. P < 0.05 is considered as statistically significant.

Results

Of 297 samples, 128 samples were found to be HPV‐positive by p16. Of total 128 HPV‐positive samples, PCR, E6, and E7 qPCR were positive in 19, 97, and 98 samples, respectively. qPCR techniques were found highly significant in the detection of moderately differentiated (P < 0.0001) and widely differentiated (P < 0.0001) cases. The positivity of E6 qPCR increased as the p16 expression increased. A significant variation in E6 DNA copies was observed in different grades of p16 expression (P < 0.0001). However, overall E7 (5.4 × 105 copies/μL) DNA copies were higher than E6 (7.7 × 103 copies/μL).

Conclusion

qPCR detection of HPV infection is a fast, reliable, and accurate technique gives valuable information about the infection status in terms of viral load.
Area usage estimation and spatiotemporal variability in distribution patterns of southern right whales, Eubalaena australis, of southern Brazil
Authors: Pires Renault‐Braga Eduardo , Rejane Groch Karina , de Carvalho Flores Paulo A. , Secchi Eduardo R. , Dalla‐Rosa Luciano
Published: July 2018

Southern right whales—Eubalaena australis (Desmoulins, 1822)—migrate seasonally from high‐latitude feeding grounds to coastal breeding and calving grounds at lower latitudes such as the southern coast of Brazil. Understanding how these whales are distributed along the coast is important for monitoring their postwhaling recovery and defining management strategies. In this study, we applied Kernel density estimators to aerial survey data to determine main occurrence and concentration areas of right whales in southern Brazil and investigate inter‐ and intra‐annual distribution patterns between 2003 and 2012. Our results show considerable variation in area usage within and among years, and changes in the general distribution pattern of right whales in the last years of the study. Intra‐annually, higher concentration area tended to expand from July to September and decrease in November. Some areas stood out as high‐density areas for right whales: Ribanceira/Ibiraquera, Itapirubá Sul/Sol, and from Arroio to Gaivota. Some evidences also suggest preferential areas for mother–calf pairs. The higher concentration area of right whales in southern Brazil was estimated at 52,541 km2 and the occurrence area was 682.69 km2, which is the whole study area. As right whale distribution in the region is likely expanding due to this population's current recovery, our study provides essential information for management plan of the Right Whale Environmental Protection Area.
Colour vision variation in leaf‐nosed bats (Phyllostomidae): Links to cave roosting and dietary specialization
Authors: Kries Kelly , Barros Marília A. S. , Duytschaever Gwen , Orkin Joseph D. , Janiak Mareike C. , Pessoa Daniel M. A. , Melin Amanda D.
Published: July 2018

Bats are a diverse radiation of mammals of enduring interest for understanding the evolution of sensory specialization. Colour vision variation among species has previously been linked to roosting preferences and echolocation form in the suborder Yinpterochiroptera, yet questions remain about the roles of diet and habitat in shaping bat visual ecology. We sequenced OPN1SW and OPN1LW opsin genes for 20 species of leaf‐nosed bats (family Phyllostomidae; suborder Yangochiroptera) with diverse roosting and dietary ecologies, along with one vespertilionid species (Myotis lavali). OPN1LW genes appear intact for all species, and predicted spectral tuning of long‐wavelength opsins varied among lineages. OPN1SW genes appear intact and under purifying selection for Myotis lavali and most phyllostomid bats, with two exceptions: (a) We found evidence of ancient OPN1SW pseudogenization in the vampire bat lineage, and loss‐of‐function mutations in all three species of extant vampire bats; (b) we additionally found a recent, independently derived OPN1SW pseudogene in Lonchophylla mordax, a cave‐roosting species. These mutations in leaf‐nosed bats are independent of the OPN1SW pseudogenization events previously reported in Yinpterochiropterans. Therefore, the evolution of monochromacy (complete colour blindness) has occurred in both suborders of bats and under various evolutionary drivers; we find independent support for the hypothesis that obligate cave roosting drives colour vision loss. We additionally suggest that haematophagous dietary specialization and corresponding selection on nonvisual senses led to loss of colour vision through evolutionary sensory trade‐off. Our results underscore the evolutionary plasticity of opsins among nocturnal mammals.
Internal validation of GPS™MONODOSE CanAur dtec‐qPCR kit following the UNE/EN ISO/IEC 17025:2005 for detection of the emerging yeast Candida auris
Authors: Martínez‐Murcia Antonio , Navarro Aaron , Bru Gema , Chowdhary Anuradha , Hagen Ferry , Meis Jacques F.
Published: July 2018

Candida auris is an emerging multidrug resistant pathogenic fungus that causes candidaemia with high mortality rates and exhibits the ability to persist within the hospital environment. Candida auris is phylogenetically closely related to Candida haemulonii, C. lusitaniae, C. pseudohaemulonii and C. duobushaemulonii and is frequently misidentified by commercial identification methods. In the present study, the GPS™ MONODOSE dtec‐qPCR kit (dried single‐dose PCR tubes) for the detection of C. auris was validated following the guidelines of the UNE/EN ISO/IEC 17025:2005, the French Standard NF T90‐471:2010 and using fast‐cycling protocols. Validation terms included in vitro specificity (inclusivity/exclusivity), quantitative phase analysis (10‐106 standard DNA copies), reliability (repeatability/reproducibility) and sensitivity (detection/quantification limits). GPS™ dtec‐qPCR kits passed validation with strict acceptance criteria (n ≥ 10 repetitions). In silico specificity was proven by the designer (GPS™). Experimental inclusiveness was achieved in two independent laboratories by testing strain JCM15448T and 117 clinical C. auris isolates from Asia, the Middle‐East Africa, Latin America and Europe. Exclusiveness was evaluated with 25 strains of closely related Candida spp. Use of the MONODOSE format provided considerable advantages allowing the detection of C. auris to be accurately achieved in less than an hour. The GPS™ MONODOSE dtec‐qPCR kit is ready to undergo clinical evaluation.
Comparison of therapeutic response of lycopene and curcumin in oral submucous fibrosis: A randomized controlled trial
Authors: Piyush Prerna , Mahajan Anshul , Singh Khushboo , Ghosh Sujoy , Gupta Sunita
Published: July 2018

Objectives

To evaluate and compare the therapeutic response of lycopene and curcumin with placebo in patients suffering from oral submucous fibrosis (OSMF) and to correlate the habit variables of smoked and smokeless tobacco products in OSMF.

Methods

A randomized placebo‐controlled parallel clinical study was conducted on ninety OSMF patients, who were divided into three treatment groups using computer‐generated randomization. Group A patients (n = 30) were given curcumin tablet (300 mg) twice daily, Group B patients (n = 30) received lycopene capsules (8 mg) twice daily, and for Group C (n = 30), placebo capsules were given once daily for a period of six months. Both the participant and outcome assessor were blinded. Pre‐ and post‐treatment comparison of mouth opening, burning sensation, tongue protrusion, and cheek flexibility was analyzed at periodic follow‐up of 9 months.

Results

The overall improvement in mouth opening, burning sensation, tongue protrusion, and cheek flexibility was 3.9 ± 4.9 mm, 4.8 ± 2.6, 5.0 ± 7.2 mm, & 0.36 ± 0.71 mm, respectively, for curcumin and 4.1 ± 4.2 mm, 5.0 ± 2.3, 2.4 ± 3.5 mm, & 0.66 ± 0.80 mm, respectively, for lycopene with the p value <0.05.

Conclusion

Statistically significant improvement in clinical findings was observed in both curcumin and lycopene treatment groups in comparison with placebo. However, the therapeutic efficacy of curcumin and lycopene was found to be almost equal in OSMF patients.
Outcomes of repeated transvenous lead extraction
Authors: Fu Haixia , Ho Gordon , Yang Mei , Huang Xinmiao , Fender Erin A. , Mulpuru Siva , Asirvatham Roshini , Pretorius Victor G. , Friedman Paul A. , Birgersdotter‐Green Ulrika , Cha Yong‐Mei
Published: July 2018

Introduction

The outcomes of repeated cardiovascular implantable electronic device (CIED) lead extraction have not been well studied. We sought to determine the indications, outcomes, and safety of repeated lead extraction procedures.

Methods

This retrospective study was conducted using data from two medical centers, including 38 patients who had undergone two or more lead extraction procedures compared to 439 patients who had a single procedure. The electronic medical records and procedural databases were reviewed to determine the indications, procedural characteristics, and outcomes. The outcomes of the first procedure were compared to the outcomes of subsequent procedures.

Results

The 5‐year cumulative probability of a repeated extraction procedure was 11% (95% confidence interval, 7%–15%). In 439 patients who underwent single lead extractions, 72% had device and lead related infections as the procedure indication compared to 39% for 38 patients who underwent repeated extraction (P < 0.001). The mean duration from device reimplant to repeated extraction procedures was 63 ± 48 months. Ninety‐eight percent of the leads were removed completely in repeated procedures, similar to the 95% success rate of the first procedure (P = 0.51). There was no significant difference in major complication rate in the first or repeated extractions (2.6% vs 5.2%, P = 0.79).

Conclusions

Repeated transvenous lead extraction is not uncommon. It had a high success rate comparable to that of the initial procedure and was not associated with an increased incidence of adverse events.
Longitudinal characteristics of resilience among adolescents: A high school student cohort study to assess the psychological impact of the Great East Japan Earthquake
Authors: Okuyama Junko , Funakoshi Shunichi , Tomita Hiroaki , Yamaguchi Takuhiro , Matsuoka Hiroo
Published: July 2018

Aim

Resilience, the ability to cope with disasters and significant life adversity, is an important factor to consider when studying the mental health of populations affected by a disaster. Although high school students in a community affected by a disaster should have specific characteristics of resilience, little has been reported on the issue. This study was designed to provide initial data regarding characteristics of the resilience of high school students affected by a catastrophe.

Methods

A total of 760 high school students in Natori City, which was devastated by the Great East Japan Earthquake in 2011, were profiled, and a 3‐year longitudinal study was conducted with 254 students who had entered the school in 2012. Resilience was evaluated with the 10‐item Connor–Davidson Resilience Scale. The Quick Inventory of Depressive Symptomatology–Japanese version, the Zung Self‐Rating Anxiety Scale, and the Impact of Event Scale–Revised were also administered to assess the students’ mental health.

Results

Among the students who entered the high school in 2012, 28.6% showed high resilience, and the proportion increased to 42.9% in 2013 and 46.6% in 2014. The Quick Inventory of Depressive Symptomatology–Japanese version and Impact of Event Scale–Revised scores decreased significantly over the 3‐year study period, but there were no significant differences in the Zung Self‐Rating Anxiety Scale scores over time.

Conclusion

This initial study profiling the characteristics of resilience among adolescents suggests that resilience is a highly changeable component of mental health among people who have faced adversity. Resilience can be a useful indicator of recovery from adversity and a target of interventions for improving mental health conditions.
Parental awareness of young children's pattern of ionic beverage consumption
Authors: Okumura Akihisa , Ida Shinobu , Ito Setsuko , Oguni Tatsuya , Suzuki Mitsuyoshi , Mori Masaaki , Shimizu Toshiaki ,   the Committee on Pediatric Nutrition of the Japanese Pediatric Society
Published: July 2018

Background

The aim of this study was to investigate consumer perception of ionic beverage consumption by young children as a potential link to their excessive use.

Methods

We studied parents’ awareness of ionic beverages and the current pattern of use in their young children using a self‐administered questionnaire.

Results

A total of 424 responses were recorded. Approximately 25–33% of parents believed that ionic beverages are good for health and rich in nutrients and vitamins, but, only 5.9% of the parents agreed with the statement that ionic beverages are safe to consume in large quantities. Regarding their use, 11 children (2.6%) were drinking ionic beverages every day or several times a week. The parents of these children were classified into the frequent use group. The rates at which parents agreed with statements that ionic beverages are good for health and rich in vitamins were higher in the frequent use group than in controls.

Conclusion

Parental awareness of ionic beverages, and current consumption patterns in their young children are generally good. Having a positive opinion about the benefits of ionic beverages was associated with excessive consumption.
Fittingness
Authors: Howard Christopher
Published: July 2018

The normative notion of fittingness figures saliently in the work of a number of ethical theorists writing in the late nineteenth and mid‐twentieth centuries and has in recent years regained prominence, occupying an important place in the theoretical tool kits of a range of contemporary writers. Yet the notion remains strikingly undertheorized. This article offers a (partial) remedy. I proceed by canvassing a number of attempts to analyze the fittingness relation in other terms, arguing that none is fully adequate. In explaining why various analyses of fittingness fail, I draw into relief certain of the relation's constitutive features and spotlight some of its interesting and important connections to various other properties. Along the way, I highlight the relation's relevance to a number of ongoing debates in normative and metanormative philosophy. I conclude by indicating some directions for further research.
Photoluminescence Rainbow from Coelenteramide—A Theoretical Study
Authors: Gao Meng , Liu Ya‐Jun
Published: July 2018

A wide variety of marine bioluminescent organisms emit light via the excited‐state coelenteramide, which is produced from the coelenterazine oxidation via a series of complicated chemical reactions in protein. Photoluminescence of coelenteramide is a simple way to produce light without experiencing the intricate reactions starting from coelenterazine. To extend the color range of light emission, many coelenterazine analogues were synthesized, but mostly only produce blue and cyan fluorescence. Based on the 42 synthesized coelenterazine analogues, we theoretically studied the absorption and fluorescence properties of the corresponding coelenteramide analogues. The electronic effect, steric effect, conjugated effect and solvated effect were considered. The results indicated that conjugated effect has great influence on the strength and wavelength of fluorescence and large electron transfer is beneficial to redshift. Based on the regularities, we theoretically designed six coelenteramide analogues, and together with the original coelenteramide, the seven‐ones emit the seven colors of rainbow via their photoluminescences. This study expands the coelenteramide fluorescence to the whole visible light region and could inspire new application.
UV exposure, preventive habits, risk perception, and occupation in NMSC patients: A case‐control study in Trieste (NE Italy)
Authors: Larese Filon Francesca , Buric Masa , Fluehler Catharina
Published: July 2018

Background

UV exposure is strongly associated with the incidence of non melanoma skin cancers (NMSCs), both basal and squamous cell carcinomas. The aim of our study was to analyze risk perception, UV exposure, preventive habits, and occupation in 126 subjects affected by NMSC and 187 controls.

Methods

Consecutive cases with incident NMSC were recruited in Dermatologic Unit at University of Trieste; controls were recruited in Unit of Occupational Medicine. All had a medical examination to define Fitzpatrick skin type and skin lesions, and filled a standardized questionnaire on sun exposure habits, sun protection, occupational exposures, and sunburns in adulthood and childhood.

Results

In multivariate regression analysis, NMSC resulted significantly associated with age (OR: 1.03; 95% CI 1.01‐1.05), with a positive feeling for tan (OR: 1.10; 95% CI 1.01‐1.20), and sunbath numbers per year (OR: 1.02; 95% CI: 1.001‐1.03). A protective effect was demonstrated for Fitzpatrick phototypes III‐IV compared to I and II (OR: 0.31; 95% CI: 0.18‐0.55), sunscreen use (OR: 0.35; 95% CI: 0.22‐0.58), and risk perception (OR: 0.98; 95% CI: 0.97‐0.99). In univariate analysis, we demonstrated an increased risk for fishermen, sailors, and lifeguards (OR: 4.3; 95% CI: 1.1‐16.4); foundry and metallurgy workers (OR: 5.58; 95% CI: 1.14‐27.3); and mechanics, fixers, and welders (OR: 8.2; 95% CI: 1.76‐37.9).

Conclusions

Our study demonstrated that protective behavior must be implemented in people living in Trieste. Workers must avoid direct UV exposure and must use protective equipment. More efforts are needed to increase knowledge on this risk and to raise awareness among at‐risk people.
Effects of continuous versus pulsed drought stress on physiology and growth of wheat
Authors: Stallmann J. , Schweiger R. , Müller C.
Published: July 2018

In the course of climate change, crop plants are exposed to both altered precipitation volumes and frequencies in many cultivation areas. Reduced water availability and longer periods without precipitation can lead to changes in plant physiology and productivity.

In this greenhouse study, we investigated physiological responses, including maximum quantum yield of photosystem II (Fv/Fm) and water use efficiency (WUE) as well as diverse productivity‐related parameters, including grain yield per plant, to continuous (irrigated three times a week) versus pulsed (once a week) irrigation in spring wheat (Triticum aestivum L.). In both drought regimes, plants were exposed to four different irrigation volumes.

Fv/Fm was not influenced by irrigation treatment but was significantly higher after 6 weeks of drought than after 2 weeks. WUE increased with decreasing irrigation volume and based on generative biomass; it was higher in continuously‐watered compared to pulsed‐watered plants that received a similar amount of water over the experiment. Infrequent irrigation led to a reduction in grain yield of up to 51%. This lower productivity was primarily caused by fewer tillers in pulsed‐watered plants. Additionally, at low water volume the thousand grain weight (TGW) was lower in infrequently‐compared to frequently‐watered plants. In contrast, the number of grains per ear was higher in pulsed‐watered plants.

In conclusion, reduced irrigation frequency, next to a decrease in irrigation volume, negatively affects WUE and grain yield of spring wheat. These results might have important implications for irrigation scheduling and breeding programmes under a changing climate.
Expression of endogenous retroviruses in pre‐implantation stages of bovine embryo
Authors: Khazaee Elaheh , Farzaneh Nima , Mirshokraei Pezhman , Tabatabaeizadeh Seyed‐Elias , Dehghani Hesam
Published: July 2018

Contents

Endogenous retroviruses (ERVs) are involved in cellular proliferation, pluripotency, tissue‐specific remodelling and regulation of developmental processes. These elements are transcriptionally active in mouse and human pre‐implantation embryos. Empirical evidence indicates that regulatory networks involved withERVtranscripts are responsible for pluripotency and totipotency at certain stages of mouse and human pre‐implantation development. Yet, the expression in pre‐implantation bovine embryo remains unidentified. To determine whether two members of bovine endogenous retroviruses,BERV‐K1 andBERV‐K2, are expressed in the pre‐implantation bovine embryo, each embryonic stage developed in vitro and was subjected toRNArelease, reverse transcription and quantitativePCR. We found thatBERV‐K1 andBERV‐K2 are expressed throughout different stages of pre‐implantation development. The higher level of expression was detected in embryonic blastomeres with totipotent/pluripotent status (two‐cell to 16‐cell stages), while the more differentiated blastocyst stage showed significantly lower levels ofERVs expression. These findings suggest a possible role for endogenous retroviruses in the establishment of totipotent and pluripotent states in pre‐implantation bovine embryo, similar to functions which have been suggested for these elements in human and mouse embryos.
Effect of different oxidative stress degrees generated by hydrogen peroxide on motility and DNA fragmentation of zebrafish (Danio rerio) spermatozoa
Authors: Sadeghi Sara , Pertusa José , Yaniz Jesús L. , Nuñez Javier , Soler Carles , Silvestre Miguel Angel
Published: July 2018

Contents

An increase in reactive oxygen species (ROS) or decrease in antioxidant barriers can provoke lipid peroxidation of the membranes or DNA damage of the spermatozoa. The aim of this work is to study the effect of the different degrees of oxidative stress generated by H2O2 incubation on total motility, kinetics, and DNA fragmentation of zebrafish (Danio rerio) spermatozoa. For this process, experimental groups were incubated in 50 µM (Low; L) and 200 µM (High; H) H2O2, respectively, for 20 min at 4ºC. Sperm motility parameters were obtained with a computer‐assisted sperm analysis (CASA) system. Sperm DNA fragmentation (SDF) was assessed using the sperm chromatin dispersion test. Both low and high H2O2 concentration groups showed lower motility than control groups. Progressive motility of spermatozoa incubated in the H group dropped rapidly in comparison with other groups. Regarding SDF, the control and L groups had significantly lower values than the H group (25.0% and 31.6% vs. 48.1% fragmented sperm for C, L, and H groups, respectively; p < 0.05). Sperm motility, mostly progressive motility, decreased as H2O2 concentration increased, mainly when time after sperm activation increased. SDF increased as the H2O2 concentration increased. However, measurements of the halo area did not agree with the subjective SDF rate.
Micromorphological analysis of liquefaction features in alluvial and coastal environments of Christchurch, New Zealand
Authors: Giona Bucci Monica , Smith Carol M. , Almond Peter C. , Villamor Pilar , Tuttle Martitia P.
Published: July 2018

This study presents a micromorphological analysis of liquefaction features (dykes, sills and sand blows) associated with the 2010 to 2011 Canterbury Earthquakes Sequence, dykes of an earlier generation of liquefaction (palaeoliquefaction) and hosting soil. The aim of this research was to determine whether diagnostic features existed that would allow robust identification of liquefaction features and discrimination of different generations of liquefaction features in thin sections. This study serves to enhance the tools available to support palaeoliquefaction studies and earthquake hazard assessment. Similarities were found in the sedimentary fabric between all forms and ages of liquefaction features distinct from hosting soil. Palaeoliquefaction features could also be distinguished on the basis of microscopic pedogenic characteristics. Liquefaction and palaeoliquefaction were investigated in two distinctive sedimentary settings: the floodplain of the Halswell River, and coastal sand dunes near or in Christchurch. Analysis was carried out on thin sections prepared from resin‐impregnated blocks of soil sediment hosting the liquefaction features. The fabric of modern liquefaction features in the alluvial and coastal system is similar, both showing a single grain micro‐structure, with moderate to well‐sorted grains with many simple packing voids and planar voids. In both environments it was possible to see evidence of fluidization such as water escape structures, cutans and silt caps. The palaeoliquefaction fabric can be distinguished from the modern liquefaction fabric by the presence of textural pedogenic features in the form of silt coating of grains, infilling of planar voids, coating and hypocoating of voids and excrement pedofeatures. The results presented in this manuscript demonstrated how thin section analysis can be a valuable tool to corroborate field identification of liquefaction features, and to discriminate between features of different relative ages where stratigraphic evidence is equivocal.
Beliefs About Evolution and Educational Attainment
Authors: Longest Kyle C. , Uecker Jeremy E.
Published: July 2018

Using panel data from the National Study of Youth and Religion, we examine the effect of beliefs about evolution in high school on several postsecondary educational outcomes. Results indicate that net of a host of background factors and potential alternative explanatory factors, there are significant associations between beliefs about evolution and pursuing or obtaining a bachelor's degree, such that pure creationists (i.e., creationists who do not allow for the possibility that God used evolution to create the world) are less likely than naturalists to be on this trajectory. Further, when they do attend college, pure creationists and flexible creationists (i.e., creationists who allow for the possibility that God used evolution) both attend less selective colleges than naturalists, and pure creationists are less likely than naturalists to major in biology. These results suggest that evolution is a morally salient issue for many that influences their educational trajectories, highlighting the role that cultural schemas can play in shaping socioeconomic status.
Cucumber ovaries inhibited by dominant fruit express a dynamic developmental program, distinct from either senescence‐determined or fruit‐setting ovaries
Authors: Shnaider Yula , Mitra Deblina , Miller Golan , Baniel Avital , Doniger Tirza , Kuhalskaya Anastasiya , Scossa Federico , Fernie Alisdair R. , Brotman Yariv , Perl‐Treves Rafael
Published: July 2018

Cucurbits represent an attractive model to explore the dynamics of fruit set, whose regulation is not fully understood, despite its importance for yield determination. A fertilized ovary must integrate signals from distant plant parts and ‘decide’ whether to set fruit, or remain inhibited and later senesce. Here, we set out to characterize first‐fruit inhibition (FFI), that is, the inhibitory effect of the first fruit on subsequent development of younger ovaries during pollination‐induced and parthenocarpic fruit set. After the first fertilized ovaries set fruit, younger fertilized ovaries remained in a temporary state of inhibition. Such ovaries preserved their size and green color, and if the older fruit were removed within a 1‐week reversibility window, they set fruit. The FFI effect was documented in both fertilized and parthenocarpic ovaries. We compared the gene expression profiles of pollinated ovaries (committed to set fruit) with respect to those affected by FFI, and to non‐pollinated ovaries (undergoing senescence). The three fates of the ovaries were characterized by wide changes in gene expression, with several specific transcripts being up‐ or down‐regulated in response to pollination, and to the presence of inhibitory fruit. Metabolic profiling was undertaken and integrated with the transcriptomic data in order to characterize early physiological changes that occur in post‐anthesis ovaries in parthenocarpic and non‐parthenocarpic genotypes. The combined results are discussed with respect to current models of fruit set and specifically with regard to FFI. Moreover, these metabolome and transcriptome data provide a valuable resource for studying ovary development and fruit set.
Development of Shroudless Francis Turbine
Authors: Nakamura Yohei , Shima Ryosuke , Komatsu Hiroki , Shiratori Saki , Miyagawa Kazuyoshi
Published: July 2018

In this study, new design concepts were structured by DOE based on internal flow evaluation by CFD to realize the efficiency improvement, reliability improvement and cost reduction of a medium or small capacity hydro turbine. As a part of new concepts, shroudless type and shroud liner type runner shape were adopted. In shroud liner type, shroud line of meridional plane shape inclines at 45 degrees to rotational axis. By adopting shroud less type, runner can be made not by casting but by cutting work. For medium or small hydroelectric power plant, cost reduction is strongly required in comparison with larger scale hydro one. By adopting shroud liner type, efficiency was improved because of mitigating secondary flow. In addition, to improve reliability, shroud partial band was bonded at inlet of runner. This plays a role to prevent runner blade from breaking by tip rubbing.

By using high-speed video camera and CFD analysis, it was clarified that runner outlet cavitation is caused by jet which is leakage in the tip clearance region and that leakage flow of outlet is larger than leakage flow of inlet.

Moreover, by using the three-hole Pitot tube, the runner outlet flow distribution was measured and the validity of the design point was verified. Finally, by measurement of pressure on the wall of the stationary parts such as the guide vane, it was clarified that the total pressure loss of guide vane increases in stream-wise direction in low mass flow rate.

In this report, the development of the shroudless Francis turbine based on the loss mechanism and flow investigation was described.
Numerical Study on the Main Coolant Pump of Sodium-Cooled Fast Reactor
Authors: Ko Sungho , Kim Yeon-tae
Published: July 2018

A numerical study was conducted to predict the performance curve of a downscaled model of the main coolant pump for a sodium-cooled fast reactor and to reduce the head loss by the optimization of the diffuser blade.

The ANSYS CFX program was utilized to obtain flow characteristics inside the pump as well as the overall pressure rise across the pump operating on- and off-design points. Computational domain was divided into several blocks to achieve high grid quality effectively and 7.5 million nodes were used totally to resolve small leakage flows as well as the flow inside the rotating impeller.

The corresponding experiment was conducted to validate CFD computed results. The comparison between the CFD and experimental data shows excellent agreement in terms of mass flow rate and head rise on and near design operating points.

The DOE (design of experiments) and RSM (response surface method)[1] were utilized to reduce the head loss by the diffuser blade in the pump. The diffuser blade was defined as four geometric parameters for DOE. The analysis of 25 cases was made to solve the output parameters for all design points which are defined by the DOE. RSM was fitting the output parameter as a function of the input parameters using regression analysis techniques. The optimized model increased the total pump head on the design point and the low mass flow rate point, but total pump head on 130% of operating mass flow rate was reduced than the initial model.
Studies of the Effect of Vortex-Control Grooves on Pressure Oscillations in a Francis Turbine Draft Tube
Authors: An Yu , Xianwu Luo , Bin Ji
Published: July 2018

In case of the hydro turbine operated deviated from the designed condition, vortex ropes usually occur in the draft tube, and consequently generate large pressure oscillations. This kind of unsteady flow phenomenon is believed to be harmful for hydropower stations. In this paper, the authors designed a runner with vortex-control grooves and numerically simulate the flow in a Francis hydro turbine using the SAS-SST turbulence model. The pressure oscillations induced by the vortex rope under several operation conditions were analyzed based on the calculation results. It is indicated that the runner with vortex-control grooves can alleviate the pressure fluctuation at part load conditions. However, vortex-control grooves may enhance the swirling flow, and cause a small hydraulic performance drop at full load conditions. Thus, the design optimization of vortex-control grooves is necessary and will be conducted in the future.
Effects of Water-Admission on the Performance of a Centrifugal Pump
Authors: Guo Xuanyu , Yu Weiping , Luo Xianwu
Published: July 2018

In order to improve the centrifugal pump performance at off-design operation condition, water-admission is introduced at the upstream of impeller inlet. This paper treats a centrifugal condensate pump with the specific speed of 216 min−1·m3/min·m. Both hydraulic and cavitation performance have been experimentally tested for the pump. For analysis, the three-dimensional cavitating turbulent flows are simulated based on RANS method and a homogeneous cavitation model for several water-admission cases. The results indicated that with the water-admission, the pump head and hydraulic efficiency increase with the water-admission pressure up to 70kPa. However, with the water-admission pressure larger than 70kPa, the pump performance drops due to a large flow rate induced upstream the pump impeller. It is also noted that the water admission is unfavorable for cavitation inception. According to the numerical result, there is a sudden increase of accumulated cavity volume inside the impeller with the water-admission pressure larger than 70kPa. Thus, the water-admission should be further studied to improve the cavitation performance.
Numerical Simulation of Flow Around Airfoil With Non-Linear RANS Model
Authors: Qun Wei , Hongxun Chen , Zheng Ma
Published: July 2018

The standard k-ε eddy viscosity model is the most commonly used model in computational fluid dynamics and perform well in application, but less effective for flows with high mean shear rate or massive separation. An non-linear eddy viscosity k-ε model was developed to compensate the deficit, in which the Cμ determined by an expression of shear strain rate rather than a constant on the base of experimental and DNS data. Two-dimensional CFD simulations were carried out by proposed NL k-ε model and standard k-ε model for wind-turbine airfoil S809 with the general purpose CFD code ANSYS CFX 12.1. Results show that standard k-ε can predict the flow around the airfoil for angles of attack with attached flow, but is not qualified for flow at angles of attack with strong flow separation, whereas non-linear k-ε model can improve the accuracy of the performance coefficients to some extent, and when large flow separation generates, non-linear k-ε model can improve the accuracy of pressure distribution around the airfoil and simulate the flow separation more correctly.
Modelling of Free Surface Flow Within the Two-Fluid Euler-Euler Framework
Authors: Porombka Paul
Published: July 2018

Two-phase flows are regularly involved in the heat and mass transfer of industrial processes. To ensure the safety and efficiency of such processes, accurate predictions of the flow field and phase distribution by means of Computational Fluid Dynamics (CFD) are required. Direct Numerical Simulations (DNS) of large-scale two-phase flow problems are not feasible due to the computational costs involved. Therefore the Euler-Euler framework is often employed for large-scale simulations which involves macro-scale modelling of the turbulent shear stress and the interphase momentum transfer.

As a long term objective, the research activities at Helmholtz-Zentrum Dresden-Rossendorf (HZDR) pursue the development of general models for two-phase flows which are based on first principles and include less empiricism. Part of this effort is focused on the development of an algebraic interfacial area density model (AIAD) which enables the simulation of two-phase flows with general morphologies including bubble, droplet and stratified flow regimes with the two-fluid approach. In this work a short overview of the AIAD model is given and recent developments are presented.

The modelling of the interfacial drag in free surface flows is of particular interest and subject to ongoing research. Apart from empirical correlations, which are limited to certain flow regimes, different models for the local calculation of the interfacial drag have been developed. The latter approach is followed in the AIAD model and has recently been subject to modifications which are presented and validated as a part of this study.

Furthermore, special attention is paid to the turbulence treatment at the phase boundary of free surface flows. A general damping of the gas-side turbulent fluctuations in the near interface region has been described previously in the literature but has not yet found its way into eddy viscosity turbulence models. In this work, a previously proposed damping source term for the k-ω turbulence model is validated.

Model validation is performed by comparing the simulation results to experimental data in case of stratified, countercurrent air-water flow in a closed channel.
Effects of Diffuser Length on Cloud Cavitation in an Axisymmetrical Convergent-Divergent Nozzle
Authors: Sato Keiichi , Takahashi Naoya , Sugimoto Yasuhiro
Published: July 2018

Unsteady behavior of periodic cloud cavitation is typically observed in the field of fluid machinery under a high speed liquid flow such as a cavitating hydrofoil as well as cavitating water jet. The instability of cloud cavitation remains to be completely solved though it has been confirmed that there are two instabilities which is an intrinsic instability of cavitation and a system instability. Sato, et al. have found through previous investigations that the pressure wave at the collapse of shedding clouds can make a trigger to cause a reentrant motion.

In the present study, the authors focus on a cavitating water jet to investigate the cavitation aspects in an axisymmetrical convergent-divergent nozzle and examine an unsteady behavior of cloud cavitation through high speed video observation and image analysis based on the frame difference method. Especially, the authors study the effect of nozzle divergent part (diffuser) as well as the upstream pressure effect on cloud cavitation in the nozzle. As a result the authors have found that there are two kinds in the shedding pattern and the reentrant motion pattern for cloud cavitation depending on the nozzle diffuser length.