bluuebunny/crossref_metadata_2025 huggingface dataset:
Trends in Risk of Pregnancy Loss Among US Women, 1990–2011
Authors: Rossen Lauren M. , Ahrens Katherine A. , Branum Amy M.
Published: October 2017

Background

Pregnancy loss can have physical and psychological consequences for women and their families. Though a previous study described an increase in the risk of self‐reported pregnancy loss from 1970 to 2000, more recent examinations from population‐based data of US women are lacking.

Methods

We used data from the 1995, 2002, 2006–2010, 2011–2015 National Survey of Family Growth on self‐reported pregnancy loss (miscarriage, stillbirth, ectopic pregnancy) among US women (15–44 years) who reported at least one pregnancy conceived during 1990–2011 that did not result in induced termination (n = 20 012 women; n = 42 526 pregnancies). Trends in the risk of self‐reported pregnancy loss and early pregnancy loss (<12 weeks) were estimated, separately, by year of pregnancy conception (limited to 1990–2011 to ensure a sufficient sample of pregnancies for each year and maternal age group) using log‐Binomial and Poisson models, adjusted for maternal‐ and pregnancy‐related factors.

Results

Among all self‐reported pregnancies, excluding induced terminations, the risk of pregnancy loss was 19.7% and early pregnancy loss was 13.5% during 1990–2011. Risk of pregnancy loss increased by a relative 2% (rate ratio [RR] 1.02, 95% confidence interval [CI] 1.01, 1.02) per year in unadjusted models and 1% per year (RR 1.01, 95% CI 1.00, 1.02) during 1990–2011, after adjustment for maternal characteristics and pregnancy‐related factors. In general, trends were similar for early pregnancy loss.

Conclusion

From 1990 to 2011, risk of self‐reported pregnancy loss increased among US women. Further work is needed to better understand the drivers of this increase in reported pregnancy loss in the US.
Perceived stress is associated with smaller hippocampal volume in adolescence
Authors: Piccolo Luciane R. , Noble Kimberly G. ,   for the Pediatric Imaging, Neurocognition, and Genetics Study
Published: October 2017

Perceived stress has been associated with decreased hippocampal, amygdala, and prefrontal cortex volume, as well as decreased memory and executive functioning performance in adulthood. Parents' perceived stress has been linked to decreased hippocampal volume in young children. However, no studies have investigated the links between self‐perceived stress and brain structure or function in adolescents. Additionally, findings from previous research with younger or older samples are inconsistent, likely in part due to inconsistencies in participants' age range. In this study, we investigated the associations among self‐perceived stress, family socioeconomic factors (family income, parental education), subcortical (hippocampus, amygdala) volumes, prefrontal cortical thickness and surface area, and memory and executive functioning performance in adolescents. One hundred and forty‐three participants (12–20 years old) were administered a cognitive battery, a questionnaire to assess perceived stress, and a structural MRI scan. Higher levels of perceived stress were associated with decreased adolescent hippocampal volume. This study provides empirical evidence of how experience may shape brain development in adolescence—a period of plasticity during which it may be possible to intervene and prevent negative developmental outcomes.
Recent developments in aquaculture of Palmaria palmata (Linnaeus) (Weber & Mohr 1805): cultivation and uses
Authors: Grote Britta
Published: October 2017

This review summarizes the recent literature on the biology, cultivation techniques and uses of the red seaweed Palmaria palmata ((Linnaeus) Weber & Mohr 1805). The paper covers its distribution, appearance and life cycle, the state of the art cultivation techniques for spore release and seeding, and the culture of meristematic fragments of fronds harvested from natural populations. Furthermore, culture conditions for P. palmata sporelings and gametophytes and set‐ups of tank and open sea culture are presented. For tank culture, relatively high irradiance and frequent seawater exchange to supply carbon dioxide and nutrients are the most important parameters. In open sea culture, site selection and system design play an important role. Land‐based culture has the advantage that optimum culture conditions can be applied and quality‐controlled, whereas nearshore cultivation is less costly and labour intensive. In addition, the bioremediation potential and the use of P. palmata in integrated multitrophic aquaculture (IMTA) are discussed. More research is needed to investigate bioremediation potential of different P. palmata strains. Recent developments in uses of P. palmata as food supplement, source of bioactive compounds, animal feed and compound for biofuels are presented. Finally, the possibilities of cultivation of P. palmata enhance the prospects for the expansion of the cultivation of this seaweed. However, future research is needed regarding balance of culture conditions, costs and biomass in land‐based tank culture and in terms of site selection, system design, maintenance and harvest techniques in sea cultivation to establish a commercialization of the aquaculture of this species in Europe.
PIWIs, piRNAs and Retrotransposons: Complex battles during reprogramming in gametes and early embryos
Authors: Russell SJ , Stalker L , LaMarre J
Published: October 2017

Contents

Gamete and embryo development are indispensable processes for successful reproduction. Cells involved in these processes acquire pluripotency, the ability to differentiate into multiple different cell types, through a series of events known as reprogramming that lead to profound changes in histone and DNA methylation. While essential for pluripotency, this epigenetic remodelling removes constraints that normally limit the expression of genomic sequences known as transposable elements (TEs). Unconstrained TE expression can lead to many deleterious consequences including infertility, so organisms have evolved complex and potent mechanistic arsenals to target and suppress TE expression during reprogramming. This review will focus on the control of transposable elements in gametes and embryos, and one important TE suppressing system known as the PIWI pathway. This broadly conserved, small RNA‐targeted silencing mechanism appears critical for fertility in many species and may participate in multiple aspects of gene regulation in reproduction and other contexts.
Coenzyme Q10 supplementation during in vitro maturation of bovine oocytes (Bos taurus) helps to preserve oocyte integrity after vitrification
Authors: Ruiz‐Conca M , Vendrell M , Sabés‐Alsina M , Mogas T , Lopez‐Bejar M
Published: October 2017

Contents

Oocyte vitrification causes less cell stress than slow cooling, but cytoskeletal and spindle alterations may occur affecting the oocyte competence. In vitro maturation (IVM) supplementation with different antioxidant molecules has been performed to attenuate this harmful stress. Coenzyme Q10 (CoQ10) supplementation has previously shown to have positive effects in bovine and mouse in vitro embryo development. The aim of this study was to evaluate the effects of CoQ10 during bovine oocyte IVM and vitrification. Cumulus–oocyte complexes (COCs) (n = 311) were cultured under standard maturation conditions with 0 μM (control), 25 μM and 50 μM CoQ10 supplementation. After 22 hr, a cohort of 170 oocytes both from the control and from CoQ10‐supplemented groups were vitrified, warmed and returned to incubation until 24 hr of maturation, while the rest of the oocytes (n = 141) remained fresh. Then, oocyte survival was assessed morphologically by stereomicroscopy. Oocytes from all groups were then fixed and stained for assessing cortical granules (CG) migration and nuclear stage. High rates of oocyte MII progression and appropriate CG migration as a continuous layer beneath the plasma membrane were obtained both in control and in CoQ10 groups. Results showed that although vitrification has great impact in survival of IVM bovine oocytes, 50 μM CoQ10 supplementation significantly improved oocyte survival (p = .045) and reduced the premature CG exocytosis, helping to preserve the CG migration pattern (31.3% control vs. 54.5% in 50 μM CoQ10; p = .039), attenuating the negative effects of vitrification.
Disease burden of mild asthma in China
Authors: Ding Bo , Small Mark
Published: October 2017

Background and objective

The impact, treatment patterns and control of mild asthma are poorly understood for Chinese patients. This study describes the characteristics, therapeutic interventions and burden of mild asthma on patients residing in major cities of China.

Methods

The Respiratory Disease Specific Program 2015, a cross‐sectional survey, was conducted with Chinese physicians and their patients. The survey assessed clinical characteristics, asthma symptoms, exacerbations, rescue inhaler usage, treatment adherence, asthma control, work and activity impairments and healthcare utilization for patients prescribed Global Initiative for Asthma (GINA) Step 1 or 2 treatment defined mild asthma.

Results

From a total sample of 988 patients, 229 patients met the criteria for mild asthma, with 25.3% classified as Step 1 and 74.7% as Step 2. Overall, 12.6% of patients were considered of high adherence to prescribed treatment. Physicians reported that 75% of patients overall were well controlled, although well‐controlled asthma as defined by GINA was achieved in only 14.2% of patients. 26.5% of patients indicated daily use of as‐needed rescue medication in the last 4 weeks. 17.8% of patients experienced ≥1 exacerbations in the last 12 months and impaired work productivity was 27.2% overall.

Conclusion

Less than 15% of patients were well controlled according to GINA criteria despite physicians reporting the majority of patients were well controlled. Over one‐fourth of patients relied on daily rescue inhaler medication, while exacerbation frequency and work and activity impairment were higher than might reasonably be expected in a mild asthmatic population.
MERS, SARS and other coronaviruses as causes of pneumonia
Authors: Yin Yudong , Wunderink Richard G.
Published: October 2017

Human coronaviruses (HCoVs) have been considered to be relatively harmless respiratory pathogens in the past. However, after the outbreak of the severe acute respiratory syndrome (SARS) and emergence of the Middle East respiratory syndrome (MERS), HCoVs have received worldwide attention as important pathogens in respiratory tract infection. This review focuses on the epidemiology, pathogenesis and clinical characteristics among SARS‐coronaviruses (CoV), MERS‐CoV and other HCoV infections.
How ‘healthy’ do children really need to be? Going beyond the limits
Authors: Simpson Shannon , Hall Graham
Published: October 2017

See related Article
Consumption dynamics and inequality of opportunity with an application to Uganda
Authors: Brunori Paolo , Palmisano Flaviana , Peragine Vito
Published: October 2017

This paper proposes the adoption of an opportunity egalitarian perspective to assess and compare growth processes and their distributional implications. To this aim, a set of graphical tools are introduced that allow one to evaluate the role of growth and recessions in the evolution of individuals’ opportunities over time. These tools satisfy the ex post principle of equality of opportunity and represent an extension of the “opportunity growth incidence curve,” a framework proposed by the literature to evaluate growth according to the ex ante principle of equality of opportunity. This measurement framework is applied to evaluate the economic dynamic between 2009 and 2011 in Uganda. The results show that despite a reduction in the real value of household consumption and a surge in outcome inequality, its effects appear to be less dramatic when the ex post equality of opportunity perspective is invoked.
Symptoms of depression in Swedish fathers in the postnatal period and development of a screening tool
Authors: Psouni Elia , Agebjörn Johan , Linder Hanne
Published: October 2017

Methods for detecting depression in fathers after the birth of their child are scarce. The Edinburgh Postnatal Depression Scale (EPDS), used to screen mothers for postpartum depression (PPD), lacks somatization and externalizing items. This potentially decreases its sensitivity in detecting depression in fathers, as many men actually express depression with somatization or externalizing symptoms. The present study assessed depressive symptoms in fathers of children 0–18 months old, and evaluated whether addressing both typical depression and externalizing, so‐called “depressive equivalent” symptoms, might be more suitable for such assessment. The Beck Depression Inventory‐II (BDI‐II), EPDS, and Gotland Male Depression Scale (GMDS) were responded to by 447 Swedish fathers online. Among participants, 27% reported depressive symptoms above the BDI‐II cut‐off suggestive of depression. Most fathers reported both traditional and depressive equivalent symptoms and a subgroup expressed exclusively depressive equivalent symptoms. Consistently, a scale combining items from the EPDS and GMDS showed higher sensitivity than the EPDS alone in identifying fathers with elevated depressive symptoms, at equal levels of specificity. Our findings suggest that a combination of EPDS and depressive equivalent symptom items results in a more suitable instrument for screening for depression in fathers during the postnatal period.
The sociology of grit: Exploring grit as a sociological variable and its potential role in social stratification
Authors: Kwon Hye Won
Published: October 2017

This paper proposes the currently fashionable psychological notion of “grit” as a potentially useful variable in sociological analysis and explores its potential for contributing to addressing sociological concerns. Grit, comprising perseverance and passion toward long‐term goals, has received growing attention within academia and from the general public as a strong predictor of achievement. Grit captures an important, noncognitive, underdeveloped aspect of agency not included in life course or stratification studies. Grit can contribute to our understanding about how the subjective beliefs that are typically treated as agency are actually translated into volitional action that constructs one's life course, a crucial potential life course mechanism. This paper suggests incorporating grit into sociological understanding of individual‐level aspects of stratification, moving beyond its current conception anchored fully in psychology, to further understand what it is, where it comes from, and why it is sociologically useful.
‘We the People’ or ‘We the Peoples’? A Comparison of Support for the Populist Radical Right and Populist Radical Left in the Netherlands
Authors: Akkerman Agnes , Zaslove Andrej , Spruyt Bram
Published: October 2017

Research on the supply side of politics demonstrates that populism acts as a common denominator even though populist parties possess very different ideological positions. However, it is uncertain whether this translates to the demand side: Do voters support left and right‐wing populist parties for similar reasons? Using the Netherlands as our case study, we investigate the common demand side characteristics of supporters of populist radical right and populist radical left parties. The paper concludes that populist attitudes (i.e. a people‐centered notion of political representation) unify supporters of both populist radical left and populist radical right parties. Supporters of both parties also demonstrate lower levels of political trust (than voters for other parties): this is particularly the case for PVV supporters. Beyond these similarities we find that the PVV and the SP attract very different supporters. PVV supporters demonstrate low immigrant tolerance, while SP voters support more income equality.
Emerging infectious disease outbreaks: estimating disease risk in Australian blood donors travelling overseas
Authors: Coghlan A. , Hoad V. C. , Seed C. R. , Flower R. LP. , Harley R. J. , Herbert D. , Faddy H. M.
Published: October 2017

Background and Objectives

International travel assists spread of infectious pathogens. Australians regularly travel to South‐eastern Asia and the isles of the South Pacific, where they may become infected with infectious agents, such as dengue (DENV), chikungunya (CHIKV) and Zika (ZIKV) viruses that pose a potential risk to transfusion safety. In Australia, donors are temporarily restricted from donating for fresh component manufacture following travel to many countries, including those in this study. We aimed to estimate the unmitigated transfusion‐transmission (TT) risk from donors travelling internationally to areas affected by emerging infectious diseases.

Materials and Methods

We used the European Up‐Front Risk Assessment Tool, with travel and notification data, to estimate the TT risk from donors travelling to areas affected by disease outbreaks: Fiji (DENV), Bali (DENV), Phuket (DENV), Indonesia (CHIKV) and French Polynesia (ZIKV).

Results

We predict minimal risk from travel, with the annual unmitigated risk of an infected component being released varying from 1 in 1·43 million to <1 in one billion and the risk of severe consequences ranging from 1 in 130 million to <1 in one billion.

Conclusion

The predicted unmitigated likelihood of infection in blood components manufactured from donors travelling to the above‐mentioned areas was very low, with the possibility of severe consequences in a transfusion recipient even smaller. Given the increasing demand for plasma products in Australia, the current strategy of restricting donors returning from select infectious disease outbreak areas to source plasma collection provides a simple and effective risk management approach.
Hierarchical evaluation of electrical stimulation protocols for chronic wound healing: An effect size meta‐analysis
Authors: Khouri Charles , Kotzki Sylvain , Roustit Matthieu , Blaise Sophie , Gueyffier Francois , Cracowski Jean-Luc
Published: October 2017

Electrical stimulation (ES) has been tested for decades to improve chronic wound healing. However, uncertainty remains on the magnitude of the efficacy and on the best applicable protocol. We conducted an effect size meta‐analysis to assess the overall efficacy of ES on wound healing, to compare the efficacy of the different modalities of electrical stimulation, and to determine whether efficacy differs depending on the wound etiology, size, and age of the chronic wound. Twenty‐nine randomized clinical trials with 1,510 patients and 1,753 ulcers were selected. Overall efficacy of ES on would healing was a 0.72 SMD (95% CI: 0.48, 1) corresponding to a moderate to large effect size. We found that unidirectional high voltage pulsed current (HVPC) with the active electrode over the wound was the best evidence‐based protocol to improve wound healing with a 0.8 SMD (95% CI: 0.38, 1.21), while evaluation of the efficacy of direct current was limited by the small number of studies. ES was more effective on pressure ulcers compared to venous and diabetic ulcers, and efficacy trended to be inversely associated with the wound size and duration. This study confirms the overall efficacy of ES to enhance healing of chronic wounds and highlights the superiority of HVPC over other type of currents, which is more effective on pressure ulcers, and inversely associated with the wound size and duration. This will enable to standardize future ES practices.
Reappraisal of systemic venous chemoreceptors: might they explain the matching of breathing to metabolic rate in humans?
Authors: Parkes M. J.
Published: October 2017

New Findings

What is the topic of this review?

One of the major unanswered questions in physiology is that of how breathing matches metabolic rate. Venous chemoreceptors seem to have been dismissed since the 1960s.

What advances does it highlight?

New evidence shows that their apparent dismissal needs reappraisal.

The paper on which this depends has more than one interpretation, and another paper obtained the opposite result.

Previous search ignored all locations between skeletal muscle and the right heart.

Oxygen sensors other than the arterial chemoreceptors do exist. Heymans and colleagues originally demonstrated some residual breathing response to hypoxia in sino‐aortically denervated animals. Similar results occur in humans.

One of the major unanswered questions in physiology is that of how breathing matches metabolic rate. The existence in humans of venous chemoreceptors that might control breathing seems to have been dismissed since the 1960s. New evidence has emerged showing that this apparent dismissal needs reappraisal. First, the paper in humans on which this depends has more than one interpretation. Moreover, a previous paper obtained the opposite result and is not cited. Secondly, previous search for venous chemoreceptors failed to examine all venous locations between skeletal muscle and the right heart and lungs. Thirdly, oxygen sensors other than the arterial chemoreceptors do exist. Heymans himself originally demonstrated some residual breathing response to hypoxia in sino‐aortically denervated animals. Others confirm a residual breathing response to hypoxia in mammals, including humans. There is now considerable interest in the importance of afferent feedback in controlling the cardiovascular and respiratory systems. Moreover, it is now clear that arterial, aortic and central chemoreceptors have no role in explaining how breathing matches metabolic rate during exercise. These together provide a timely reminder that venous chemoreceptors remain ideal candidates still to be considered as metabolic rate sensors to explain matching in humans. Firstly, this is because venous and values do change appropriately in proportion to metabolic rate, so a metabolic rate signal sufficient to drive breathing might already exist. Secondly, chemoreceptor‐like anatomical structures are present in the systemic venous system but remain unexplored. Finally, no extant experimental evidence precludes their existence.
Architecture and Suppression Design of Alarm System in HTR-PM
Authors: Guo Chao , Jia Qianqian , Huang Xiaojin , Zhou Shuqiao
Published: October 2017

Nuclear safety is one of the key issues for a nuclear power plant (NPP). The alarm system plays a critical role for the safe and efficient operation of an NPP which is a significant human-machine interface in the main control room. The multi-modular NPPs have multiple reactor modules coupled to one steam turbine. One critical problem for the multi-modular NPP is that the complexity of the alarm system is greatly increased, which threatens the human-factor safety and the operation reliability. On the other hand, the main control room usually suffers from too many alarms to be handled at the same time after the accident, which is difficult for the operator to find out specific initiating event and may cause severe accident. The High Temperature Gas-Cooled Reactor - Pebble bed Module (HTR-PM) which is under construction in Shandong province of China, is a typical multi-modular NPP with two reactor modules coupled to one steam turbine. In this paper, the architecture of the alarm system of HTR-PM is introduced. Different from conventional full-digital alarm system in the NPPs, a set of alarm tiles which are set up at the top of the large display panel are adopted to improve the alarm identification, and the alarm tiles are classified to groups of reactor 1#, conventional island, and reactor 2#, respectively. These alarm tiles cooperates with the alarm indication on the visual display unit to help to locate the accident location as soon as possible. The suppression design in case of alarm overloading are also discussed in this paper. Techniques like the dead band and first alarm indication are adopted in the alarm system of HTR-PM. Two kinds of suppression logics on condition and priority are discussed in the end of this paper. The work showed in this paper can contribute to improve the design of alarm systems in other NPPs, especial the multi-modular NPPs.
The Research of XLPE Cable Comprehensive Performance Evaluation Based on VLF Technology
Authors: Xuan Gao , Zheng Zheng , Yizhou Zhang , Liang Wang , Hao Yun , Ge Tao , Huiming Ma , Kun Xue
Published: October 2017

Very low frequency (VLF) technology can effectively evaluate the damp cable aging condition, and IEEE 400.2 formulate the dielectric diagnostic indicators and standards of the VLF technology, but this technology is not popular in Chinese nuclear power station. The paper has carried on 0.1Hz VLF dielectric loss test, insulation resistance test on three 10kV XLPE power cables which have same specifications but different operation environment. Combined those electric test with the cable history environment information, the result shows it’s very useful for the cable comprehensive performance evaluation.
Stress Improvement by Laser Peening in the Air
Authors: Ueno Souichi , Tsuji Akihiro , Adachi Hiroyuki , Naito Tatsuya
Published: October 2017

Underwater laser peening (LP) system has been developed for the purpose of preventing occurrence of Stress Corrosion Cracking. Toshiba has already applied LP for actual nuclear reactors, such as Control-Rot Drive housings in BWR and bottom mounted instrumentations in PWR and so on. At the same time, LP system in the air is expected since Reactor Vessel Head (RVH) is set on an operating floor during outage. In this study, LP system in the air was proposed which employs laser beam irradiation with concentric water jet. LP uses shock waves made by underwater confinement of plasma generated during laser abrasion which enables to induce compressive residual stress at 1mm in depth by optimizing laser energy, laser spot diameter and pulse density. A water jet has the functions of transmitting a laser beam without attenuating power and creating partial under water environment in the air. Hence potential core, which has no disturbance area in a water jet, should be increased in diameter and longer in distance from nozzle exit. LP tests in the air were performed by using the developed nozzles and measurements of residual stress were conducted. Test conditions are below; 70 mJ in laser energy, 1.0 mm in spot diameter, more than 30 mm in distance from nozzle exit to irradiation point, 36 shot/mm2 in pulse density, 90 degree in irradiation angle between laser axis and surface direction of irradiated area. Material of specimens was Alloy 600 nickel based alloy. Residual stress was measured by X-ray diffraction. It was confirmed that stress state at 1.0 mm in depth from the surface indicates compressive stress. These results concluded that LP in the air was conducted successfully.
The Chemistry Experience Summary During the Engineering Commissioning Period of Fujian Ningde Nuclear Power Plant
Authors: Liu Heng , Chen Yue , Li Fuping , Liu Hui , Yang Shunlong
Published: October 2017

In chemical researchers view, hot functional test is a verification of the Nuclear Power Plant before first fuel loading and commercial operation, which is the preparation for staffs, documents, instruments and sampling systems. So, chemistry department should use its own language, knowledge and experience to express their thoughts and what they have seen during the engineering commissioning period. As the first commercial operation nuclear power plant after Fukushima nuclear accident, during the four units commissioning period, chemical researchers accumulated a lot of good experience and feedbacks in the aspect of construction and commissioning for new nuclear power plant. For example, in order to ensure the personnel skill level, we must make special plans which include staff training, laboratory construction, instrument and on-line system commissioning, and all of these should be timely adjusted and changed in order to be consistent with the engineering progress. In order to ensure the water quality of pipe flushing in different stages, such as cold functional test, hot functional test, we should set a strictly water chemical standard which based on the HAF103, and the standard should have some differences in different stage for one unit. In order to ensure the water chemistry in good performance especially after the unit going into commercial operation, the maintenance plan for equipment and system must be formulated, and then, a detailed monitoring plan must be executed. At the same time, a strict system flushing controlling mode can also provide a great benefits for water chemistry quality, especially in the period of start-up. In addition to these above experiences, chemistry researchers of Ningde nuclear power plant also accumulated a lot of good practices and feedbacks about dealing with some abnormal water quality activities, which can’t be founded in commercial operation unit. For example, the aluminum (Al) content in the primary increased rapidly and beyond the specification limits in hot functional test and so on. This article will share the good practices and feedbacks of the first phase of Fujian Ningde nuclear power plant. We hope these good practices and experience feedbacks can provide good reference for the other new nuclear plants in the stage of design, construction, operation and maintenance in the future.
Hierarchical Structure Modeling for the Analysis of I&C System Software Reliability
Authors: Bo-wen Zou , Ming Yang , Zhen-yu Yan , Xin-yu Dai , Hidekazu Yoshikawa
Published: October 2017

A Software life cycle (SLC) is used to describe the phases of software cycle and ensure the good quality software is built. A software system can be regard as hierarchical and composed of a set of interacting system elements. The system elements will be implemented to fulfill its respective specified requirements. In this paper, as a complex software system, system element also is an entire system. Software hierarchical model has applied commonly in various software analysis areas like software complexity analysis, software reliability allocation analysis, etc. A software reliability hierarchical structure modeling (SRHSM) is proposed for the analysis of the software stages before it being used, which are concept stage, development stage and production stage. Based on the preliminary work, the concepts of SRSHM method is optimized, and increased some basic elements. RSHSM method comprises two processes in SLC, including Partition and Composition process, and is divided into four levels, System level, Subsystem level, Unit level, Code level. Particularly, under the less information condition, this method can be used in the initial stage of SLC to design and analyze the software.
Improvement of the RELAP5-3D Model of Condensation in the Presence of Noncondensables
Authors: Anderson Nolan A. , Mesina George L.
Published: October 2017

Condensation of steam on the primary side of a steam generator in a pressurized water reactor (PWR) is one means of removing decay heat during some accident scenarios, including small break loss of coolant accident (SBLOCA). However, when noncondensable gasses mix with steam, it impairs condensation. To correctly predict plant behavior, nuclear power plant (NPP) safety analysis codes such as RELAP5-3D must model the effect of condensation in the presence of noncondensables properly.

A potential error in the RELAP5-3D code was reported in the condensation model in the presence of noncondensables by the University of Wisconsin[1]. The report indicated that the calculated condensation heat flux was under-predicted due to the modeling of the mass transfer in the gas mixture. The original documentation describing the implementation of the model was reviewed and compared with alternative formulations. An alternative that uses saturation vapor density at temperature of total pressure instead of the saturation vapor density at vapor partial pressure for calculating vapor mass flux was implemented. Comparison of the alternative method with the original against experimental data for several test cases showed improvement for most test cases.
Reflecting boundary conditions for interferometry by multidimensional deconvolution
Authors: Weemstra Cornelis , Wapenaar Kees , van Dalen Karel N.
Published: October 2017

In an acoustical context, interferometry takes advantage of existing (ambient) wavefield recordings by turning receivers into so-called “virtual sources.” The medium's response to these virtual sources can be harnessed to image that medium. Most interferometric applications, however, suffer from the fact that the retrieved virtual-source responses deviate from the true medium responses. The accrued artefacts are often predominantly due to a non-isotropic illumination of the medium of interest, and prohibit accurate interferometric imaging. Recently, it has been shown that illumination-related artefacts can be removed by means of a so-called multidimensional deconvolution (MDD) process. However, the current MDD formulation, and hence method, relies on separation of waves traveling inward and outward through the boundary of the medium of interest. As a consequence, it is predominantly useful when receivers are illuminated from one side only. This puts constraints on the applicability of the current MDD formulation to omnidirectional wavefields. In this paper, a modified formulation of the theory underlying interferometry by MDD is presented. This modified formulation eliminates the requirement to separate inward and outward propagating wavefields and, consequently, holds promise for the application of MDD to non-isotropic, omnidirectional wavefields.
Influence of glottal closure on the phonatory process in ex vivo porcine larynges
Authors: Birk Veronika , Kniesburges Stefan , Semmler Marion , Berry David A. , Bohr Christopher , Döllinger Michael , Schützenberger Anne
Published: October 2017

Many cases of disturbed voice signals can be attributed to incomplete glottal closure, vocal fold oscillation asymmetries, and aperiodicity. Often these phenomena occur simultaneously and interact with each other, making a systematic, isolated investigation challenging. Therefore, ex vivo porcine experiments were performed which enable direct control of glottal configurations. Different pre-phonatory glottal gap sizes, adduction levels, and flow rates were adjusted. The resulting glottal closure types were identified in a post-processing step. Finally, the acoustic quality, aerodynamic parameters, and the characteristics of vocal fold oscillation were analyzed in reference to the glottal closure types. Results show that complete glottal closure stabilizes the phonation process indicated through a reduced left-right phase asymmetry, increased amplitude and time periodicity, and an increase in the acoustic quality. Although asymmetry and periodicity parameter variation covers only a small range of absolute values, these small variations have a remarkable influence on the acoustic quality. Due to the fact that these parameters cannot be influenced directly, the authors suggest that the (surgical) reduction of the glottal gap seems to be a promising method to stabilize the phonatory process, which has to be confirmed in future studies.
A Novel Steroid-Coenzyme A Ligase from Novosphingobium sp. Strain Chol11 Is Essential for an Alternative Degradation Pathway for Bile Salts
Authors: Yücel Onur , Holert Johannes , Ludwig Kevin Christopher , Thierbach Sven , Philipp Bodo
Published: October 2017

Bile salts such as cholate are steroid compounds with a C
5
carboxylic side chain and occur ubiquitously in vertebrates. Upon their excretion into soils and waters, bile salts can serve as growth substrates for diverse bacteria.
Novosphingobium
sp. strain Chol11 degrades 7-hydroxy bile salts via 3-keto-7-deoxy-Δ
4,6
metabolites by the dehydration of the 7-hydroxyl group catalyzed by the 7α-hydroxysteroid dehydratase Hsh2. This reaction has not been observed in the well-studied 9-10-seco degradation pathway used by other steroid-degrading bacteria indicating that strain Chol11 uses an alternative pathway. A reciprocal BLASTp analysis showed that known side chain degradation genes from other cholate-degrading bacteria (
Pseudomonas stutzeri
Chol1,
Comamonas testosteroni
CNB-2, and
Rhodococcus jostii
RHA1) were not found in the genome of strain Chol11. The characterization of a transposon mutant of strain Chol11 showing altered growth with cholate identified a novel steroid-24-oyl–coenzyme A ligase named SclA. The unmarked deletion of
sclA
resulted in a strong growth rate decrease with cholate, while growth with steroids with C
3
side chains or without side chains was not affected. Intermediates with a 7-deoxy-3-keto-Δ
4,6
structure, such as 3,12-dioxo-4,6-choldienoic acid (DOCDA), were shown to be likely physiological substrates of SclA. Furthermore, a novel coenzyme A (CoA)-dependent DOCDA degradation metabolite with an additional double bond in the side chain was identified. These results support the hypothesis that
Novosphingobium
sp. strain Chol11 harbors an alternative pathway for cholate degradation, in which side chain degradation is initiated by the CoA ligase SclA and proceeds via reaction steps catalyzed by so-far-unknown enzymes different from those of other steroid-degrading bacteria.

IMPORTANCE
This study provides further evidence of the diversity of metabolic pathways for the degradation of steroid compounds in environmental bacteria. The knowledge about these pathways contributes to the understanding of the CO
2
-releasing part of the global C cycle. Furthermore, it is useful for investigating the fate of pharmaceutical steroids in the environment, some of which may act as endocrine disruptors.
Conditional Function of Autoaggregative Protein Cah and Common
cah
Mutations in Shiga Toxin-Producing Escherichia coli
Authors: Carter Michelle Qiu , Brandl Maria T. , Kudva Indira T. , Katani Robab , Moreau Matthew R. , Kapur Vivek
Published: October 2017

Cah is a calcium-binding autotransporter protein involved in autoaggregation and biofilm formation. Although
cah
is widespread in Shiga toxin-producing
Escherichia coli
(STEC), we detected mutations in
cah
at a frequency of 31.3% in this pathogen. In STEC O157:H7 supershedder strain SS17, a large deletion results in a smaller coding sequence, encoding a protein lacking the C-terminal 71 amino acids compared with Cah in STEC O157:H7 strain EDL933. We examined the function of Cah in biofilm formation and host colonization to better understand the selective pressures for
cah
mutations. EDL933-Cah played a conditional role in biofilm formation
in vitro
: it enhanced
E. coli
DH5α biofilm formation on glass surfaces under agitated culture conditions that prevented autoaggregation but inhibited biofilm formation under hydrostatic conditions that facilitated autoaggregation. This function appeared to be strain dependent since Cah-mediated biofilm formation was diminished when an EDL933
cah
gene was expressed in SS17. Deletion of
cah
in EDL933 enhanced bacterial attachment to spinach leaves and altered the adherence pattern of EDL933 to bovine recto-anal junction squamous epithelial (RSE) cells. In contrast, in
trans
expression of EDL933
cah
in SS17 increased its attachment to leaf surfaces, and in DH5α, it enhanced its adherence to RSE cells. Hence, the ecological function of Cah appears to be modulated by environmental conditions and other bacterial strain-specific properties. Considering the prevalence of
cah
in STEC and its role in attachment and biofilm formation,
cah
mutations might be selected in ecological niches in which inactivation of Cah would result in an increased fitness in STEC during colonization of plants or animal hosts.

IMPORTANCE
Shiga toxin-producing
Escherichia coli
(STEC) harbors genes encoding diverse adhesins, and many of these are known to play an important role in bacterial attachment and host colonization. We demonstrated here that the autotransporter protein Cah confers on
E. coli
DH5α cells a strong autoaggregative phenotype that is inversely correlated with its ability to form biofilms and plays a strain-specific role in plant and animal colonization by STEC. Although
cah
is widespread in the STEC population, we detected a mutation rate of 31.3% in
cah
, which is similar to that reported for
rpoS
and
fimH
. The formation of cell aggregates due to increased bacterium-to-bacterium interactions may be disadvantageous to bacterial populations under conditions that favor a planktonic state in STEC. Therefore, a loss-of-function mutation in
cah
is likely a selective trait in STEC when autoaggregative properties become detrimental to bacterial cells and may contribute to the adaptability of STEC to fluctuating environments.
A Canonical Biotin Synthesis Enzyme, 8-Amino-7-Oxononanoate Synthase (BioF), Utilizes Different Acyl Chain Donors in Bacillus subtilis and Escherichia coli
Authors: Manandhar Miglena , Cronan John E.
Published: October 2017

BioF (8-amino-7-oxononanoate synthase) is a strictly conserved enzyme that catalyzes the first step in assembly of the fused heterocyclic rings of biotin. The BioF acyl chain donor has long been thought to be pimeloyl-CoA. Indeed,
in vitro
the
Escherichia coli
and
Bacillus sphaericus
enzymes have been shown to condense pimeloyl-CoA with
l
-alanine in a pyridoxal 5′-phosphate-dependent reaction with concomitant CoA release and decarboxylation of
l
-alanine. However, recent
in vivo
studies of
E. coli
and
Bacillus subtilis
suggested that the BioF proteins of the two bacteria could have different specificities for pimelate thioesters in that
E. coli
BioF may utilize either pimeloyl coenzyme A (CoA) or the pimelate thioester of the acyl carrier protein (ACP) of fatty acid synthesis. In contrast,
B. subtilis
BioF seemed likely to be specific for pimeloyl-CoA and unable to utilize pimeloyl-ACP. We now report genetic and
in vitro
data demonstrating that
B. subtilis
BioF specifically utilizes pimeloyl-CoA.

IMPORTANCE
Biotin is an essential vitamin required by mammals and birds because, unlike bacteria, plants, and some fungi, these organisms cannot make biotin. Currently, the biotin included in vitamin tablets and animal feeds is made by chemical synthesis. This is partly because the biosynthetic pathways in bacteria are incompletely understood. This paper defines an enzyme of the
Bacillus subtilis
pathway and shows that it differs from that of
Escherichia coli
in the ability to utilize specific precursors. These bacteria have been used in biotin production and these data may aid in making biotin produced by biotechnology commercially competitive with that produced by chemical synthesis.
Draft Genome Sequence of a Salmonella enterica Serovar Typhi Strain Resistant to Fourth-Generation Cephalosporin and Fluoroquinolone Antibiotics
Authors: Gul Danish , Potter Robert F. , Riaz Hurmat , Ashraf Shifa Tariq , Wallace Meghan A. , Munir Tehmina , Ali Amjad , Burnham Carey-Ann , Dantas Gautam , Andleeb Saadia
Published: October 2017

Typhoid is endemic in developing countries. We report here the first draft genome sequence of a
Salmonella enterica
serovar Typhi clinical isolate from Pakistan exhibiting resistance to cefepime (a fourth-generation cephalosporin) and fluoroquinolone antibiotics, two of the last-generation therapies against this pathogen. The genome is ~4.8 Mb, with two putative plasmids.
Genome Sequence of an Alphaherpesvirus from a Beluga Whale (
Delphinapterus leucas
)
Authors: Davison Andrew J. , Nielsen Ole , Subramaniam Kuttichantran , Jacob Jessica M. , Romero Carlos H. , Burek-Huntington Kathy A. , Waltzek Thomas B.
Published: October 2017

Beluga whale alphaherpesvirus 1 was isolated from a blowhole swab taken from a juvenile beluga whale. The genome is 144,144 bp in size and contains 86 putative genes. The virus groups phylogenetically with members of the genus
Varicellovirus
in subfamily
Alphaherpesvirinae
and is the first alphaherpesvirus sequenced from a marine mammal.
Laryngeal closure impedes non-invasive ventilation at birth
Authors: Crawshaw Jessica R , Kitchen Marcus J , Binder-Heschl Corinna , Thio Marta , Wallace Megan J , Kerr Lauren T , Roehr Charles C , Lee Katie L , Buckley Genevieve A , Davis Peter G , Flemmer Andreas , te Pas Arjan B , Hooper Stuart B
Published: October 2017

Background

Non-invasive ventilation is sometimes unable to provide the respiratory needs of very premature infants in the delivery room. While airway obstruction is thought to be the main problem, the site of obstruction is unknown. We investigated whether closure of the larynx and epiglottis is a major site of airway obstruction.

Methods

We used phase contrast X-ray imaging to visualise laryngeal function in spontaneously breathing premature rabbits immediately after birth and at approximately 1 hour after birth. Non-invasive respiratory support was applied via a facemask and images were analysed to determine the percentage of the time the glottis and the epiglottis were open.

Hypothesis

Immediately after birth, the larynx is predominantly closed, only opening briefly during a breath, making non-invasive intermittent positive pressure ventilation (iPPV) ineffective, whereas after lung aeration, the larynx is predominantly open allowing non-invasive iPPV to ventilate the lung.

Results

The larynx and epiglottis were predominantly closed (open 25.5%±1.1% and 17.1%±1.6% of the time, respectively) in pups with unaerated lungs and unstable breathing patterns immediately after birth. In contrast, the larynx and the epiglottis were mostly open (90.5%±1.9% and 72.3%±2.3% of the time, respectively) in pups with aerated lungs and stable breathing patterns irrespective of time after birth.

Conclusion

Laryngeal closure impedes non-invasive iPPV at birth and may reduce the effectiveness of non-invasive respiratory support in premature infants immediately after birth.
Familial history aggregation on acute appendicitis
Authors: Simó Alari Francesc , Gutierrez Israel , Gimenéz Pérez Judit
Published: October 2017

Appendectomy is the most commonly performed surgical procedure, affecting 1%–8% of the paediatric population, with a total 7% lifetime risk, most likely in adolescents and young adults.

A case of familial aggregation was reported in our hospital in a family composed of nine siblings from which six of them (66.6%) had been treated of acute appendicitis, five of them in our centre.

Many factors have been described as predisposing to appendicitis. Several studies have highlighted the influence of genes in the evolution of this disease and its severity, demonstrating a relative risk increase by three when family history is present.

Family history of acute appendicitis is an important factor to be taken into consideration during the medical interview. Clinicians attempting to fine-tune their diagnostic accuracy when patients present with acute abdominal pain should inquire about family history of appendicitis.
Learning from errors: unnecessary intensive care unit admissions
Authors: Rambarat Cecil A , Winchester David E
Published: October 2017

An elderly man was transferred to our emergency department with reported ventricular tachycardia requiring intravenous amiodarone and intensive care unit admission. Device interrogation, the following day, revealed only frequent premature ventricular contractions and non-sustained ventricular tachycardia in a patient with a known history of these conditions. The patient underwent unnecessary invasive monitoring after being emergently transferred to our facility and admitted to the intensive care unit. Fortunately, our patient did not suffer any unwarranted side effects from intravenous amiodarone. This case reports on some negative consequences of inappropriate intensive care unit admissions and how they could have been avoided.