bluuebunny/crossref_metadata_2025 huggingface dataset:
Transient Subcooled Flow Boiling Phenomena in a Vertical Small Tube
Authors: Nakamura Yuji , Liu Qiusheng , Shibahara Makoto , Hata Koichi , Fukuda Katsuya
Published: December 2019

In this research, the transient heat transfer due to exponentially increasing heat input was experimentally measured for upward water flowing in a vertical small tube. The heat generation rate was increased exponentially with a function of Qoexp (t/τ), where, Qo is an initial heat generation rate, t represents time and τ is e-folding time. The heat generation rate was controlled by high speed computer system. The test tube was heated with exponentially increasing heat input by direct current. The average temperature of test tube was measured by resistance thermometry using a double bridge circuit. The experimental apparatus consists of a test section, a cooler, a heater, a pump, a tank and a pressurizer. The working fluid was distilled and deionized water. The inlet fluid temperature of test tube was controlled by the cooler and the heater. The system pressure was up to 800 kPa. The test tube was 0.7 mm in inner diameter and 12.0 mm in heated length respectively. The ratio of heated length to inner diameter was 17.1. The test tube was electrically isolated from experimental loop by Bakelite plates. The experimental data were compared with previous correlations of nucleate boiling. It was obtained that the experimented data agree well with full-developed flow boiling correlation by Rohsenow. Moreover, the transient critical heat flux (CHF) and nucleate boiling with onset of nucleate boiling (ONB) values increased with the increase in flow velocity. The transient CHFs and ONBs increased with a decrease in e-folding time at τ < 1 s, and they approached steady-state value at τ > 1 s. It was understood that the heat transfer is in steady-state at τ > 1 s, and it is in transient state at τ < 1 s.
On the Stefan Problem With Internal Heat Generation and Prescribed Heat Flux Conditions at the Boundary
Authors: Barannyk Lyudmyla , Williams Sidney D. V. , Ogidan Olufolahan Irene , Crepeau John C. , Sakhnov Alexey
Published: December 2019

We study the evolution of the solid-liquid interface during melting and solidification of a material with constant internal heat generation and prescribed heat flux at the boundary for a plane wall and a cylinder. The equations are solved by splitting them into transient and steady-state components and then using separation of variables. This results in an ordinary differential equation for the interface that involves infinite series. The initial value problem is solved numerically, and solutions are compared to the previously published quasi-static solutions. We show that when the internal heat generation and the heat flux at the boundary are close in value to each other, the motion of the phase change front takes longer to reach steady-state than when the values are farther apart. As the difference between the internal heat generation and the heat flux increases, the transient solutions become more dominant and the numerical solution of the phase change front does not reach steady-state before the outer boundary or centerline is reached. The difference between the internal heat generation and the heat flux at the boundary can be used to control the motion and speed of the interface. The problem has applications for a nuclear fuel rod during meltdown.
A Hybrid Absorption System With Generator Level Optical Control and Variable Flow Rate
Authors: Souza Gleidson , Vargas José V. C. , Balmant Wellington , Campos Marcos C. , Martinez Leonardo C. , Ordóñez Juan C. , Mariano André B.
Published: December 2019

Current refrigeration and air conditioning systems are mostly based on the vapor compression cycle, which require electrical energy input. Absorption systems have gained new interest due to the possibility of utilizing waste heat as energy input. In addition, the environmental impact generated by such systems is recognized as much smaller than vapor compression systems. Therefore, this work developed and characterized an absorption refrigeration system with an innovative generator level optical control and variable working fluid mass flow rate, with potential for use in industrial, commercial and residential heating, ventilation, air conditioning, and refrigeration (HVAC & R) systems. The system is hybrid, since it was designed to be fed with heat from the burning of different fuels and/or waste heat sources in complementary fashion. The system consists of: a condenser, an evaporator, two expansion valves, two absorbers, a centrifugal pump, a regenerative heat exchanger, a generator, a rectifier, a generator level optical control system, and two liquid accumulators. The developed level control system consists of 3 light Dependent Resistors (LDR) positioned inside a box built around a transparent level meter, and illuminated internally by a low power light bulb. A frequency inverter and a centrifugal pump allow for the working fluid solution inside the generator to be within a safe range for efficient cooling cycle operation. The system measured refrigeration capacity rate was 2.3 TR, which qualifies as a good performance, since the equipment was originally designed for 1 TR.
Thermal Mixing Downstream of a 90-Degree T-Junction: Laminar and Turbulent Flows
Authors: Farouk Bakhtier
Published: December 2019

A three-dimensional time dependent computational fluid dynamic (CFD) study of laminar and turbulent thermal mixing of two flows entering a 90° T-junction pipe is presented. The two incoming flows (both liquids) in the T-junction enter the flow domain with different inlet velocities, and temperatures. Water flow is considered in both the horizontal pipe and the vertical pipe. Inlet temperature differences and temperature dependent thermophysical properties are considered. Large eddy simulations (LES) with sub-grid scale (SGS) modeling were considered for the simulation of the turbulent cases. The flow characteristics, and thermal mixing behaviors and detailed mixing structures were simulated, and they showed that thermal mixing of the two streams are closely affected by the inlet conditions of the two streams and the inlet thermophysical properties of the two streams.
Diurnal Profiles of Physical Activity and Postures Derived From Wrist-Worn Accelerometry in UK Adults
Authors: Perez-Pozuelo Ignacio , White Thomas , Westgate Kate , Wijndaele Katrien , Wareham Nicholas J. , Brage Soren
Published: December 2019

Background: Wrist-worn accelerometry is the commonest objective method for measuring physical activity in large-scale epidemiological studies. Research-grade devices capture raw triaxial acceleration which, in addition to quantifying movement, facilitates assessment of orientation relative to gravity. No population-based study has yet described the interrelationship and variation of these features by time and personal characteristics. Methods: 2,043 United Kingdom adults (35–65 years) wore an accelerometer on the non-dominant wrist and a chest-mounted combined heart-rate-and-movement sensor for 7 days free-living. From raw (60 Hz) wrist acceleration, we derived movement (non-gravity acceleration) and pitch and roll (forearm) angles relative to gravity. We inferred physical activity energy expenditure (PAEE) from combined sensing and sedentary time from approximate horizontal arm angle coupled with low movement. Results: Movement differences by time-of-day and day-of-week were associated with forearm angles; more movement in downward forearm positions. Mean (SD) movement was similar between sexes ∼31 (42) mg, despite higher PAEE in men. Women spent longer with the forearm pitched >0°, above horizontal (53% vs 36%), and less time at <0° (37% vs 53%). Diurnal pitch was 2.5–5° above and 0–7.5°below horizontal during night and daytime, respectively; corresponding roll angles were ∼0° (hand flat) and ∼20° (thumb-up). Differences were more pronounced in younger participants. All diurnal profiles indicated later wake-times on weekends. Daytime pitch was closer to horizontal on weekdays; roll was similar. Sedentary time was higher (17 vs 15 hours/day) in obese vs normal-weight individuals. Conclusions: More movement occurred in forearm positions below horizontal, commensurate with activities including walking. Findings suggest time-specific population differences in behaviors by age, sex, and BMI.
Beset by neural tube defects, Ethiopia may fortify salt
Authors: Wadman Meredith
Published: December 2019

Government wants evidence of effectiveness before adding folic acid to ubiquitous dietary staple.
Impact of Suboptimal APOBEC3G Neutralization on the Emergence of HIV Drug Resistance in Humanized Mice
Authors: Hernandez Matthew M. , Fahrny Audrey , Jayaprakash Anitha , Gers-Huber Gustavo , Dillon-White Marsha , Audigé Annette , Mulder Lubbertus C. F. , Sachidanandam Ravi , Speck Roberto F. , Simon Viviana
Published: December 2019

Both viral (e.g., RT) and host (e.g., A3G) factors can contribute to HIV sequence diversity. This study shows that suboptimal anti-A3G activity shapes viral fitness and drives viral evolution in the plasma compartment in humanized mice.
Draft Genome Sequences of Mycobacterium tuberculosis Clinical Isolates from the Ural Region of Russia That Carry the
pks15/1
Gene
Authors: Shur Kirill V. , Zakharevich Natalia V. , Akimova Natalia I. , Yunes Roman A. , Frolova Svetlana G. , Maslov Dmitry A. , Danilenko Valery N.
Published: December 2019

Here, we report the draft genome sequences of 15
Mycobacterium tuberculosis
isolates of the Beijing-B0/W-148 sublineage that carry a 7-bp insertion within the
pks15
gene, which leads to the synthesis of Pks15/1 fusion protein. Pks15/1 is involved in phenolglycolipid synthesis and biofilm formation, thus potentially contributing to the B0/W-148 lineage’s enhanced virulence and drug resistance.
Child with ‘46, XX’ disorder of sex development: clues to diagnose aromatase deficiency
Authors: Agrawal Saurav Shishir , Chakraborty Partha Pratim , Sinha Anirban , Maiti Animesh
Published: December 2019

A diagnosis of congenital adrenal hyperplasia (CAH) in a ‘46, XX’ newborn with ambiguous genitalia is like a ‘knee jerk reaction’ of the paediatrician because of its higher frequency and life-threatening consequences if remain undiagnosed and hence untreated. Aromatase deficiency (AD), a rare cause of ‘46, XX’ disorder of sex development, mimics virilising CAH in many aspects; thus, the disease is often overlooked. Diagnosis of AD in women is much easier around puberty due to the presence of primary amenorrhoea, undeveloped breasts, androgen excess and tall stature with eunuchoid proportions. Diagnosing AD with confidence immediately after birth or during early childhood is a challenging task without genetic analysis. In resource-restricted settings, AD remains a diagnosis of exclusion particularly in this age group and history of maternal virilisation, non-progressive genital ambiguity, elevated gonadotrophins (follicle-stimulating hormone >>luteinising hormone), mildly delayed bone age with/without enlarged polycystic ovaries serve as important clues to the underlying AD.
Association between age-related macular degeneration and subjective cognitive complaints
Authors: Zhu Zhuoting , Liao Huan , Wang Wei , Scheetz Jane , Zhang Jian , He Mingguang
Published: December 2019

Purpose

To investigate the association between age-related macular degeneration (AMD) and subjective cognitive complaints (SCCs) in the USA.

Methods

A total of 5604 participants aged 40 years and older from the 2005–2008 National Health and Nutrition Examination Survey were included. Retinal photography was graded into no AMD, early and late AMD based on the modification of the Wisconsin Age-Related Maculopathy Grading System. SCCs were based on the self-reported difficulty in remembering or confusion. Sample weights were used to generate nationally representative data. Multivariate regression analyses were used to assess the association between AMD severity and SCCs, controlling for potential confounders.

Results

Participants with any AMD had higher prevalence of SCCs relative to participants without AMD (6.8% vs 13.6%, p<0.001). After adjusting for potential confounding factors, presence of any AMD was significantly associated with 1.62-fold higher odds of having SCCs (95% CI 1.16 to 2.27, p=0.007). Similarly, participants with early (OR 1.58; 95% CI 1.14 to 2.17, p=0.007) and late AMD (OR 2.02; 95% CI 1.08 to 3.79, p=0.030) were also associated with elevated odds of reporting SCCs after controlling for confounders.

Conclusions

We found significant associations between AMD severity and SCCs in this US population. More attention should be paid on the subjective memory function and potential risk of cognitive decline among patients with AMD.
Has Gavi lived up to its promise? Quasi-experimental evidence on country immunisation rates and child mortality
Authors: Jaupart Pascal , Dipple Lizzie , Dercon Stefan
Published: December 2019

Introduction

Gavi, the Vaccine Alliance, was set up in 2000 to improve access to vaccines for children living in the poorest countries. Funding has increased significantly over time, with Gavi disbursements reaching US $1.58 billion in 2015. We assess whether Gavi’s funding programmes have indeed increased immunisation coverage in 51 recipient countries for two key vaccines for 12–23 month olds: combined diphtheria, pertussis and tetanus (DPT) and measles. Additionally, we look at effects on infant and child mortality.

Methods

Taking a difference-in-differences quasi-experimental approach to observational data, we estimate the impact of Gavi eligibility on immunisation coverage and mortality rates over time, using WHO/UNICEF figures covering 1995–2016. We control for economy size and population of each country as well as running a suite of robustness checks and sensitivity tests.

Results

We find large and significant positive effects from Gavi’s funding programmes: on average a 12.02 percentage point increase in DPT immunisation coverage (95% CI 6.56 to 17.49) and an 8.81 percentage point increase in measles immunisation coverage (95% CI 3.58 to 14.04) over the period to 2016. Our estimates show Gavi support also induced 6.22 fewer infant deaths (95% CI −10.47 to −1.97) and 12.23 fewer under-five deaths (95% CI −19.66 to −4.79) per 1000 live births.

Conclusion

Our findings provide evidence that Gavi has had a substantial impact on the fight against communicable diseases for improved population and child health in lower-income countries. In this case, the health policy to verticalise aid—specifically development assistance for health—via a specialised global fund has had positive outcomes.
Protocol for a scoping review on information needs and information-seeking behaviour of people with dementia and their non-professional caregivers
Authors: Au Shu Ting , Soong Aijia , Kyaw Bhone Myint , Tudor Car Lorainne
Published: December 2019

Background

Dementia is a debilitating disease that can lead to major changes in a patient’s behaviour and function. It is important to educate both patients with dementia and their non-professional caregivers about the disease. Yet, currently available sources do not seem to be effective for patients and caregivers, who report a need for more information and guidance. A systematic identification of the patients’ and caregivers’ needs for information and information-seeking behaviour is needed to create information resources that are relevant and beneficial to the target population.

Objectives

This is a protocol for a scoping review aimed at gathering knowledge on the information needs and information-seeking behaviour of patients with dementia and their non-professional caregivers. Our aim was also to provide recommendations for development of future dementia information resources.

Methods

The study will commence in November 2018. Both quantitative and qualitative studies on the information needs of patients with dementia or caregivers will be examined using Arksey and O’Malley’s methodological framework for scoping studies. A comprehensive literature search will be conducted in electronic databases and grey literature sources. We will also screen reference lists of included studies and related systematic reviews for additional eligible studies. Two authors will perform screening of citations for eligibility and independently extract data from the included studies in parallel. Any discrepancies will be resolved through discussion. The findings will be presented through a narrative synthesis and reported in line with PreferredReporting Items for Systematic Reviews and Meta-Analyses reporting guidelines.

Ethics and dissemination

In this review, all included data will originate from published literature. Ethics approval is therefore not a requirement. We will present our findings at relevant conferences and will submit them for publication in peer-reviewed journals.
Vitamin D prescribing in children in UK primary care practices: a population-based cohort study
Authors: Wan Mandy , Horsfall Laura J , Basatemur Emre , Patel Jignesh Prakash , Shroff Rukshana , Rait Greta
Published: December 2019

Objective

To examine temporal changes in the incidence and patterns of vitamin D supplementation prescribing by general practitioners (GPs) between 2008 and 2016.

Design

Population-based cohort study.

Setting

UK general practice health records from The Health Improvement Network.

Participants

Children aged 0 to 17 years who were registered with their general practices for at least 3 months.

Outcome measures

Annual incidence rates of vitamin D prescriptions were calculated, and rate ratios were estimated using multivariable Poisson regression to explore differences by sociodemographic factors. Data on the type of supplementation, dose, dosing schedule, linked 25-hydroxyvitamin D (25(OH)D) laboratory test results and clinical symptoms suggestive of vitamin D deficiency were analysed.

Results

Among 2 million children, the crude annual incidence of vitamin D prescribing increased by 26-fold between 2008 and 2016 rising from 10.8 (95% CI: 8.9 to 13.1) to 276.8 (95% CI: 264.3 to 289.9) per 100 000 person-years. Older children, non-white ethnicity and general practices in England (compared with Wales/Scotland/Northern Ireland) were independently associated with higher rates of prescribing. Analyses of incident prescriptions showed inconsistent supplementation regimens with an absence of pre-supplementation 25(OH)D concentrations in 28.7% to 56.4% of prescriptions annually. There was an increasing trend in prescribing at pharmacological doses irrespective of 25(OH)D concentrations, deviating in part from UK recommendations. Prescribing at pharmacological doses for children with deficient status increased from 3.8% to 79.4%, but the rise was also observed in children for whom guidelines recommended prevention doses (0% to 53%). Vitamin D supplementation at pharmacological doses was also prescribed in at least 40% of children with no pre-supplementation 25(OH)D concentrations annually.

Conclusions

There has been a marked and sustained increase in vitamin D supplementation prescribing in children in UK primary care. Our data suggests that national guidelines on vitamin D supplementation for children are not consistently followed by GPs.
Prevalence of bullying in the nursing workplace and determinant factors: a nationwide cross-sectional Polish study survey
Authors: Serafin Lena Izabela , Czarkowska-Pączek Bożena
Published: December 2019

Objectives

In the present study, we aimed to investigate the prevalence of bullying among Polish nurses, and to identify the most common negative acts, as well as individual and work-related risk factors for workplace bullying.

Methods

Cross-sectional study designed using an online survey. The total study sample was 404 nurses, each having over 6 months of working experience. Data were collected using the Polish version of the Negative Act Questionnaire-Revised. Linear stepwise regression analysis and logistic regression analysis were performed to assess predictors of greater reporting of perceived workplace bullying

Results

Bullying was experienced by 65.84% of participants. Perceived workplace bullying was associated with sex (p=0.043), age (p=0.003), seniority (p=0.006), number of working hours per week (p=0.010) and position (p=0.029). Logistic regression analysis with the dependent variable of bullying according to Leymann’s rigorous criteria revealed that the model could include four variables: age from 50 to 59, seniority of 11–15 years,>45 working hours per week and a bachelor’s degree in nursing.

Conclusions

An alarming percentage of nurses were victims of bullying. Among all variables included in the regression model, the most significant predictors of perceived workplace bullying were age, seniority, work overtime and bachelor’s degree education. Bullying prevention and improvement of well-being at work must be addressed as part of an overall strategy to deal with turnover.
Physician, heal thyself: a cross-sectional survey of doctors’ personal prescribing habits
Authors: Hartnett Yvonne , Drakeford Clive , Dunne Lisa , McLoughlin Declan M , Kennedy Noel
Published: December 2019

Background

Self-prescribing and prescribing to personal contacts is explicitly discouraged by General Medical Council guidelines.

Aims

This study examines how widespread the practice of self-prescribing and prescribing to personal contacts is.

Methods

A 16-item questionnaire was distributed via an online forum comprising 4445 young medical doctors (representing 20% of all Irish registered doctors), which asked respondents about previous prescribing to themselves, their families, friends and colleagues, including the class of medication prescribed. Demographic details were collected including medical grade and specialty.

Results

A total of 729 responses were obtained, the majority of which were from young non-consultant hospital doctors from a range of specialties. Two-thirds of respondents had self-prescribed, over 70% had prescribed to family, and nearly 60% had prescribed to a friend or colleague. Older doctors were more likely to self-prescribe (χ2=17.51, p<0.001). Interns being less likely to self-prescribe was not unexpected (χ2=69.55, p<0.001), while general practitioners (GPs) and paediatricians were more likely to self-prescribe (χ2=13.33, p<0.001;χ2=11.35, p<0.001). GPs, paediatricians and hospital medicine specialties were more likely to prescribe to family (χ2=5.19, p<0.05;χ2=8.38, p<0.05;χ2=6.17, p<0.05) and surgeons were more likely to prescribe to friends (χ2=15.87, p<0.001). Some 3% to 7% who had self-prescribed had prescribed an opiate, benzodiazepine or psychotropic medication. Male doctors, anaesthetists and surgeons were more likely to self-prescribe opioids (χ2=7.82, p<0.01;χ2=7.31, p<0.01;χ2=4.91, p<0.05), while those in hospital medicine were more likely to self-prescribe psychotropic medications (χ2=5.47, p<0.05).

Conclusion

Prescribing outside the traditional doctor-patient relationship is widespread despite clear professional guidance advising against it.
Computational study of energetic derivatives of 3,3′-bridged ditriazoles
Authors: Khan Raza Ullah , Zhu Weihua
Published: December 2019

A series of energetic bridged ditriazole was designed by incorporating different bridges and substituents into 4H-1,2,4-triazole ring. The geometrical structures, heats of formation, detonation properties, electronic structures, thermodynamic properties, free spaces, impact sensitivities, and thermal stabilities of the designed compounds were evaluated by employing density functional theory. The results elucidate that the –N3 substituent and –N=N– bridge can sufficiently increase their heats of formation. The calculated values of detonation properties show that –NF2, –ONO2, –O–, and –N=N(O)– are useful structural fragments to improve their detonation performance. The incorporation of the oxy (–O–) bridge increases their HOMO–LUMO energy gaps. An analysis of h50 values indicate that most of the designed compounds are less sensitive. The N(ring)-NO2 bond in the majority of the derivatives may be a possible trigger bond in thermal decomposition process. The incorporation of –CH2–CH2– and –O– is helpful to enhance their thermal stabilities. Based on appropriate thermal stabilities and superb detonation properties, six compounds were screened as promising high energy density compounds.
Generated land systems: recognition and prospects of land system science
Authors: Li Fei , Zhou Meijun , Qin Zhangxuan
Published: December 2019

Although land system research has made important progress in land change monitoring, long-term histories of land use change, land system change modeling, and case-study synthesis, it still faces some challenges in system integration and comprehensive analysis. To better understand and explore the comprehensiveness of land systems, system integration theory should be combined with system generation theory that emphasizes historical accumulation. Therefore, this paper revisits some of the basic connotations and theories of land system science by reviewing relevant research and proposes the concept of generated land systems based on system generation theory with an aim to providing a reference base for future research. As coupled human–environment systems are generated by mankind’s transformation, utilization, and adaptation of the land surface and its upper and lower spaces of Earth, generated land systems evolve in the mutual generation and restriction of the biophysical environment, land use, and social economy. The evolution forms of generated land systems can be classified as fluctuation, degradation, and optimization based on the ascendency and resilience of the system. The need for generated land systems to be multi-functional is what motivates the direction and form of generated land system evolution. Generation mechanism, process, adaptability, scale effect, and tele-coupling are important issues of generated land system research. In addition, how generated land systems can enter a new evolutionary cycle through functional transformation is also crucial to achieving sustainable management and utilization of land resources.
The Ramsey theory of the universal homogeneous triangle-free graph
Authors: Dobrinen Natasha
Published: December 2019

The universal homogeneous triangle-free graph, constructed by Henson [A family of countable homogeneous graphs, Pacific J. Math. 38(1) (1971) 69–83] and denoted [Formula: see text], is the triangle-free analogue of the Rado graph. While the Ramsey theory of the Rado graph has been completely established, beginning with Erdős–Hajnal–Posá [Strong embeddings of graphs into coloured graphs, in Infinite and Finite Sets. Vol.[Formula: see text] , eds. A. Hajnal, R. Rado and V. Sós, Colloquia Mathematica Societatis János Bolyai, Vol. 10 (North-Holland, 1973), pp. 585–595] and culminating in work of Sauer [Coloring subgraphs of the Rado graph, Combinatorica 26(2) (2006) 231–253] and Laflamme–Sauer–Vuksanovic [Canonical partitions of universal structures, Combinatorica 26(2) (2006) 183–205], the Ramsey theory of [Formula: see text] had only progressed to bounds for vertex colorings [P. Komjáth and V. Rödl, Coloring of universal graphs, Graphs Combin. 2(1) (1986) 55–60] and edge colorings [N. Sauer, Edge partitions of the countable triangle free homogenous graph, Discrete Math. 185(1–3) (1998) 137–181]. This was due to a lack of broadscale techniques. We solve this problem in general: For each finite triangle-free graph [Formula: see text], there is a finite number [Formula: see text] such that for any coloring of all copies of [Formula: see text] in [Formula: see text] into finitely many colors, there is a subgraph of [Formula: see text] which is again universal homogeneous triangle-free in which the coloring takes no more than [Formula: see text] colors. This is the first such result for a homogeneous structure omitting copies of some nontrivial finite structure. The proof entails developments of new broadscale techniques, including a flexible method for constructing trees which code [Formula: see text] and the development of their Ramsey theory.
Approximating the covariance ellipsoid
Authors: Mendelson Shahar
Published: December 2019

We explore ways in which the covariance ellipsoid [Formula: see text] of a centered random vector [Formula: see text] in [Formula: see text] can be approximated by a simple set. The data one is given for constructing the approximating set is [Formula: see text] that are independent and distributed as [Formula: see text]. We present a general method that can be used to construct such approximations and implement it for two types of approximating sets. We first construct a set [Formula: see text] defined by a union of intersections of slabs [Formula: see text] (and therefore [Formula: see text] is actually the output of a simple neural network). We show that under minimal assumptions on [Formula: see text] (e.g. [Formula: see text] can be heavy-tailed) it suffices that [Formula: see text] to ensure that [Formula: see text]. In some cases (e.g. if [Formula: see text] is rotation invariant and has marginals that are well behaved in some weak sense), a smaller sample size suffices: [Formula: see text]. We then show that if the slabs are replaced by well-chosen ellipsoids, the same degree of approximation is true when [Formula: see text]. The construction is based on the small-ball method.
Roles of LRRC26 as an auxiliary γ1-subunit of large-conductance Ca2+-activated K+ channels in bronchial smooth muscle cells
Authors: Noda Sayuri , Suzuki Yoshiaki , Yamamura Hisao , Giles Wayne R. , Imaizumi Yuji
Published: December 2019

In visceral smooth muscle cells (SMCs), the large-conductance Ca2+-activated K+ (BK) channel is one of the key elements underlying a negative feedback mechanism that is essential for the regulation of intracellular Ca2+ concentration. Although leucine-rich repeat-containing (LRRC) proteins have been identified as novel auxiliary γ-subunits of the BK channel (BKγ) in several cell types, its physiological roles in SMCs are unclear. The BKγ expression patterns in selected SM tissues were examined using real-time PCR analyses and Western blotting. The functional contribution of BKγ1 to BK channel activity was examined by whole cell patch-clamp in SMCs and heterologous expression systems. BKγ1 expression in mouse bronchial SMCs (mBSMCs) was higher than in other several SMC types. Coimmunoprecipitation and total internal reflection fluorescence imaging analyses revealed molecular interaction between BKα and BKγ1 in mBSMCs. Under voltage-clamp, steady-state activation of BK channel currents at pCa 8.0 in mBSMCs occurred in a voltage range comparable to that of reconstituted BKα/BKγ1 complex. However, this range was much more negative than in mouse aortic SMCs (mASMCs) or in HEK293 cells expressing BKα alone and β-subunit (BKβ1). Mallotoxin, a selective activator of BK channel that lacks BKγ1, dose-dependently activated BK currents in mASMCs but not in mBSMCs. The abundant expression of BKγ1 in mBSMCs extensively facilitates BK channel activity to keep the resting membrane potential at negative values and prevents contraction under physiological conditions.
Hypertrophic Cardiomyopathy and Wolff-Parkinson-White Syndrome in a Young African Soldier with Recurrent Syncope
Authors: Talle Mohammed Abdullahi , Buba Faruk , Bonny Aimé , Baba Musa Mohammed
Published: December 2019

Syncope is a common manifestation of both hypertrophic cardiomyopathy (HCM) and Wolff-Parkinson-White (WPW) syndrome. The most common arrhythmia in HCM is ventricular tachycardia (VT) and atrial fibrillation (AF). While preexcitation provides the substrate for reentry and supraventricular tachycardia (SVT), AF is more common in patients with preexcitation than the general population. Concurrence of HCM and WPW has been reported in many cases, but whether the prognosis or severity of arrhythmia is different compared to the individual disorders remains unsettled. We report a case of HCM and Wolff-Parkinson-White (WPW) syndrome in a 28-year-old male Nigerian soldier presenting with recurrent syncope and lichen planus.
Effects of Mental Fatigue on Small-World Brain Functional Network Organization
Authors: Li Gang , Luo Youdong , Zhang Zhengru , Xu Yanting , Jiao Weidong , Jiang Yonghua , Huang Shan , Wang Chengwu
Published: December 2019

Brain functional network has been widely applied to investigate brain function changes among different conditions and proved to be a small-world-like network. But seldom researches explore the effects of mental fatigue on the small-world brain functional network organization. In the present study, 20 healthy individuals were included to do a consecutive mental arithmetic task to induce mental fatigue, and scalp electroencephalogram (EEG) signals were recorded before and after the task. Correlations between all pairs of EEG channels were determined by mutual information (MI). The resulting adjacency matrices were converted into brain functional networks by applying a threshold, and then, the clustering coefficient (C), characteristic path length (L), and corresponding small-world feature were calculated. Through performing analysis of variance (ANOVA) on the mean MI for every EEG rhythm, only the data of α1 rhythm during the task state were emerged for the further explorations of mental fatigue. For a wide range of thresholds, C increased and L and small-world feature decreased with the deepening mental fatigue. The pattern of the small-world characteristic still existed when computed with a constant degree. Our present findings indicated that more functional connectivities were activated at the mental fatigue stage for efficient information transmission and processing, and mental fatigue can be characterized by a reduced small-world network characteristic. Our results provide a new perspective to understand the neural mechanisms of mental fatigue based on complex network theories.
Fabrication of Polypropylene-g-(Diallylamino Triazine) Bifunctional Nonwovens with Antibacterial and Air Filtration Activities by Reactive Extrusion and Melt-Blown Technology
Authors: Liu Chao , Dai Zijian , Zhou Rong , Ke Qinfei , Huang Chen
Published: December 2019

Air filtration materials such as protective masks can protect humans from airborne pathogens; however, most of the existing protective filtration materials are aimed to intercept bacteria. Therefore, in this work, modified polypropylene- (PP-) based melt-blown nonwovens with antibacterial property were prepared for reducing the infection rate during the filtering process. Firstly, an N-halamine precursor, 2,4-diamino-6-diallylamino-1,3,5-triazine (NDAM) monomer, was grafted with PP polymers (PP-g-NDAM) by reactive extrusion method, and the grafting effect was confirmed by nitrogen analysis and FTIR spectra. Then, the obtained PP-g-NDAM was mixed with pristine PP resins in different ratios to prepare the filter materials by melt-blown technology. Finally, the new PP-g-NDAM melt-blown filter materials were finishing treated by the chlorination and electrostatic process, which showed a high filtration efficiency with low pressure drop and a potent antibacterial effect against Escherichia coli (E. coli). This work provides an innovative method for manufacturing antibacterial filtration nonwovens, which can improve the quality of conventional filtration products.
Analysis of Toll-Like Receptors in Human Milk: Detection of Membrane-Bound and Soluble Forms
Authors: Cattaneo Chiara , Caramaschi Alice , Uga Elena , Braghin Michela , Cosi Gianluca , Peila Chiara , Strozzi Maria C. , Sabatini Miriam , Gazzolo Diego , Manfredi Marcello , Cavaletto Maria
Published: December 2019

The bioactive and anti-inflammatory role of human milk components has been recognized; active milk components include soluble forms of Toll-like receptors (TLRs). Preterm babies are more susceptible to infections and may succumb to necrotizing enterocolitis (NEC), a gastrointestinal disease which is exacerbated by an excessive inflammatory response after TLR activation. Here, we investigated the presence of Toll-like receptors TLR1/2/4/6 in colostrum and mature milk of women who delivered before (preterm) or after (term) 37 weeks of gestational age, integrating classical immune-related techniques with proteomic LC-MS/MS analysis. We have detected immunoreactivity for TLRs mostly in preterm samples, even for TLR1 and TLR6, until now not described in human milk. We demonstrated the presence of only TLR2 in the milk fat globule membrane, while the immunoreactivity of TLR1/4/6 was ascribed to crossreaction with some interesting milk proteins sharing leucine-rich repeat domains. These results will provide new insights into the definition of the role of TLRs in intestinal immune regulation of the newborns.
Effects of Ginsenoside Rg1 Regulating Wnt/β-Catenin Signaling on Neural Stem Cells to Delay Brain Senescence
Authors: Xiang Yue , Wang Shun-he , Wang Lu , Wang Zi-ling , Yao Hui , Chen Lin-bo , Wang Ya-ping
Published: December 2019

This is a study on the relationship between the protective effect of ginsenoside Rg1 on senescent neural stem cells and Wnt-β/catenin signaling pathway. Background. Recent studies have shown that overactivation of the Wnt/β-catenin signaling pathway is closely related to stem cell senescence. Whether Rg1 delays the senescence of NSCs is related to the regulation of this signaling pathway. Methods. The whole brain of Nestin-GFP transgenic newborn rat was extracted, and NSCs were extracted and cultured to P3 generation. The following indicators were detected: (1) NSC culture identification, (2) the effect of LiCl on the proliferation and survival rate of NSCs, (3) the effect of ginsenoside Rg1 on the proliferation and survival of NSCs, (4) the growth of NSCs in each group observed by an optical microscope, (5) the cell cycle of each group detected by flow cytometry, (6) the proliferative ability of each group detected by BrdU, (7) the fluorescence intensity of Nestin and Sox2 of NSCs in each group observed by a fluorescence microscope, (8) the positive rate of senescence staining analyzed by SA-β-Gal staining, (9) the localization of β-catenin in NSCs observed by laser confocal microscopy, and (10) the changes of the Wnt/β-catenin pathway-related proteins in each group detected by Western blotting. Results. LiCl activates the Wnt/β-catenin pathway and promotes mouse neural stem cell senescence. Ginsenoside Rg1 promotes proliferation of neural stem cells and inhibits Wnt/β-catenin pathway activation. Conclusions. LiCl can activate the Wnt/β-catenin signaling pathway of NSCs, and ginsenoside Rg1 can antagonize the senescence of NSCs caused by activation of the Wnt/β-catenin signaling pathway and delay brain aging.
The Effect of Waxing Options on Shelf Life and Postharvest Quality of “ngowe” Mango Fruits under Different Storage Conditions
Authors: Maina Benson , Ambuko Jane , Hutchinson Margaret J. , Owino Willis O.
Published: December 2019

Mango is an economically important fruit crop but with a very short shelf life of about 4–9 days in ambient and between 2 and 3 weeks in cold storage. Extending the shelf life and marketing period of mango fruit requires application of quality preservation technologies. This study aimed at evaluating the effect of innovative waxing options on shelf life and postharvest quality of “ngowe” mango fruits stored under different storage conditions. A homogenous sample of mango fruits, variety “ngowe” harvested at mature green stage were subjected to two waxing treatments, namely Shellac or Decco wax™. The waxes were applied by dipping the fruits in wax for five seconds followed by air drying. The waxed fruits were then packed in carton boxes and stored either at ambient room temperature (25°C) or cold room (12°C). Random samples of three fruits from each treatment and storage conditions were taken for measurement of attributes associated with ripening after every 3 and 7 days for ambient and cold storage, respectively. These included cumulative weight loss, respiration, peel firmness, total soluble solids (TSS), total titratable acidity (TTA) and beta carotene content. Results from the study showed that waxing with either Shellac or Decco wax was effective in prolonging shelf life of “ngowe” mango fruits by 3 and 6 days in ambient and cold storage respectively. Untreated fruits in ambient storage lost 5.3% of the initial weight by day 7 compared to an average of 4.5% for the waxed fruit (day 10). Waxed fruits in ambient had low CO2 concentration (59.53 ml/kg hr) compared to a high (88.11 ml/kg hr) CO2 concentration for the untreated fruits. Similarly, other ripening related changes including brix, color, and firmness were significantly slowed down by waxing, especially under cold storage. Findings from this study show the effectiveness of waxing in delaying mango fruit ripening. Waxing can therefore be used to extend the shelf life and marketing period for mango fruit.
Using pCO2 Gap in the Differential Diagnosis of Hyperlactatemia Outside the Context of Sepsis: A Physiological Review and Case Series
Authors: Waldauf Petr , Jiroutkova Katerina , Duska Frantisek
Published: December 2019

Introduction. There is an inverse relationship between cardiac output and the central venous-arterial difference of partial pressures of carbon dioxide (pCO2 gap), and pCO2 gap has been used to guide early resuscitation of septic shock. It can be hypothesized that pCO2 gap can be used outside the context of sepsis to distinguish type A and type B lactic acidosis and thereby avoid unnecessary fluid resuscitation in patients with high lactate, but without organ hypoperfusion. Methods. We performed a structured review of the literature enlightening the physiological background. Next, we retrospectively selected a series of case reports of nonseptic critically ill patients with elevated lactate, in whom both arterial and central venous blood gases were simultaneously measured and the diagnosis of either type A or type B hyperlactataemia was conclusively known. In these cases, we calculated venous-arterial CO2 and O2 content differences and pCO2 gap. Results. Based on available physiological data, pCO2 can be considered as an acceptable surrogate of venous-arterial CO2 content difference, and it should better reflect cardiac output than central venous saturation or indices based on venous-arterial O2 content difference. In our case report of nonseptic patients, we observed that if global hypoperfusion was present (i.e., in type A lactic acidosis), pCO2 gap was elevated (>1 kPa), whilst in the absence of it (i.e., in type B lactic acidosis), pCO2 gap was low (<0.5 kPa). Conclusion. Physiological rationale and a small case series are consistent with the hypothesis that low pCO2 gap in nonseptic critically ill is suggestive of the absence of tissue hypoperfusion, mandating the search for the cause of type B lactic acidosis rather than administration of fluids or other drugs aimed at increasing cardiac output.
Irregularity Indices of Dendrimer Structures Used as Molecular Disrupter in QSAR Study
Authors: Chen Zhihua , Virk Abaid ur Rehman , Habib Mustafa , Zia Tariq Javed , Ahmed Imran , Shi Ce , Nazeer Waqas
Published: December 2019

Dendrimers are rising polymeric structures known for their flexibility in medication conveyance and high usefulness, whose properties are same biomolecules. These nanostructured macromolecules have shown potential capacities in capturing as well as conjugating the high subatomic weight hydrophilic/hydrophobic substances by host-visitor collaborations and covalent holding (prodrug approach) individually. In quantitative structure-property relationships (QSPR), topological indices are utilized to gather properties of dendrimers. Topological indices catch symmetry of dendrimer structures and give it a logical reasoning to predict properties, for instance, viscosity, boiling points, the radius of gyrations, etc. In this report, we intend to examine dendrimers through irregularity indices that are valuable in QSPR studies. We studied sixteen irregularity indices if diverse dendrimer structures.
Magic Angle Spinning and Truncated Field Concept in NMR
Authors: Jenczyk J.
Published: December 2019

In order to thoroughly comprehend and adequtely interpret NMR data, it is necessary to perceive the complex structure of spin Hamiltonian. Although NMR principles have been extensively discussed in a number of distinguished introductory publications, it still remains difficult to find illustrative graphical models revealing the tensorial nature of spin interaction. Exposure of the structure standing behind mathematical formulas can clarify intangible concepts and provide a coherent image of basic phenomena. This approach is essential when it comes to hard to manage, time-dependent processes such as Magic Angle Spinning (MAS), where the anisotropic character of the spin system interactions couple with experimentally introduced time evolution processes. The presented work concerns fundamental aspects of solid state NMR namely: the uniqueness of the tetrahedral angle and evolution of both dipolar D and chemical shield σ coupling tensors under MAS conditions.
Noncoding RNAs in Unexplained Recurrent Spontaneous Abortions and Their Diagnostic Potential
Authors: Jia Ningyi , Li Jian
Published: December 2019

Unexplained recurrent spontaneous abortion (URSA) is defined as the loss of two or more consecutive pregnancies before the 20th week of gestation with normal findings on routine screening tests. Our understanding of the cellular and molecular pathogenesis of URSA is still far from complete. Noncoding RNAs (ncRNAs) play a pivotal role in transcription and expression. The functions of ncRNAs may also improve understanding of URSA pathogenesis. Because of their stability in the circulatory system and at the maternal-fetal interface, it may be possible to use ncRNAs as biomarkers for certain disease states. Here, we provide a narrative review of the current state of knowledge about ncRNAs associated with URSA. The possibility of developing a diagnostic tool using ncRNAs is discussed. The underlying mechanisms of how ncRNAs may lead to the onset of URSA are explored in this review.
Numerical Simulation of Mixing Characteristics in the Eccentric Rotor Extruder with Different Process Conditions and Structural Parameters
Authors: Fan De-jun , Yang Ming-kai , Huang Zhi-gao , Wen Jin-song
Published: December 2019

Numerical simulation was performed with the computational fluid dynamics analysis software POLYFLOW to investigate the influence of different process conditions and structural parameters on mixing characteristics of the eccentric rotor extruder. The intensity of shear and elongational flow strengthened when the rotational speed increased, but the time for material to stay in the extruder will be reduced. At the same time, the increase of radius and eccentricity could effectively promote the mixing performance. On the contrary, the mixing capacity reduced with the increase of the pitch. The results can be useful to optimize the structure design and guide production.