bluuebunny/crossref_metadata_2025 huggingface dataset:
An Electromechanical Model for Electrowetting
Authors: Huang Deng , Qian Fang , Zhang Wenyao , Zhao Cunlu , Li Wenbo , Wang Qiuwang
Published: December 2019

We present an electromechanical model for analysis of electrowetting by considering the balance between an electric force and a surface tension force acting on the contact line of three phases, namely the droplet (D) phase the substrate (S) phase and the ambiance (A) phase. We show that the electric force acting on the three-phase contact line generally is contributed by the Maxwell stresses at the ambiance-substrate (A-S) interface, the droplet-substrate (D-S) interface, and the droplet-ambiance (D-A) interface. It was identified that the change of contact angle in electrowetting is essentially a consequence of the modification of the electric force on the contact line. For a classical electrowetting configuration, we show that the electric force on the contact line is mainly due to the Maxwell stresses at the D-A interface. Then we examine comprehensively how the electric force on the contact line varies with the permittivity difference between A and S phases, the contact angle and size. It was found that our model agrees excellently with the classical Yong-Lippmann (Y-L) model when the permittivities of A and S phases are equal, while the difference between the two increases as the permittivity difference between A and S phases increases. The electric force increases with the increase of the contact angle for a given droplet size. Our model approaches the Y-L model with the increasing droplet size. The findings are complementary to the classical Y-L model and provide new insights into the electrowetting.
Thermal Property Enhancement of Liquid Metal Used As Thermal Interface Material by Mixing Magnetic Particles
Authors: Ma Xianfeng , Li Gen , Zheng Xuelin , Wang Xiaozhong , Wang Zhongcheng , Ji Yulong
Published: December 2019

The usage of low melting temperature alloys (LMAs) as thermal interface materials (TIMs) has attracted more and more attention for their high thermal conductivity. However, the wettability between liquid metal and ordinary metal surface was poor, which results in high thermal interface resistance. The thermal and physical properties of LMAs can be modified by adding nano or micro particles. In this study, the room temperature liquid metal (gallium, indium and tin eutectic) was used as TIM and its properties were modified by mixing magnetic nickel particles. Further, the effects of magnetic field application on the thermal performance of modified LMAs were evaluated by steady state method with specially designed sample holder. Results showed that the thermal conductivity of liquid metal mixed with nickel particle increased from 27.33 W/(m · K) to 33.33 W/(m · K) with the application of magnetic field.
Numerical and Experimental Investigation of Boiling Heat Transfer for Subcooled Water Flowing in a Small-Diameter Tube
Authors: Shibahara Makoto , Liu Qiusheng , Hata Koichi , Fukuda Katsuya
Published: December 2019

Numerical simulation of boiling heat transfer for subcooled water flowing in a small-diameter tube was conducted using the commercial computational fluid dynamics (CFD) code, PHOENICS ver. 2013. A small-diameter tube (d = 1.0–2.0 mm) was modeled in the simulation. A uniform heat flux with an exponential function was given at the inner tube wall as the boundary conditions. The inner wall boundary condition was set to a non-slip. The inlet temperature ranged from 302 to 312 K. The flow velocities of d = 1.0 mm and d = 2.0 mm are 9.29 m/s and 2.34 m/s, respectively. The transient analysis was carried out from the non-boiling region since the heat flux increased with time in the author’s experiments. The governing equations including the energy equation were discretized using the finite volume method in the PHOENICS code. The SIMPLE method was applied for the numerical simulation. For modeling boiling phenomena in the tube, the Eulerian-Eulerian two-fluid model was adopted using the interphase slip algorithm of PHOENICS code. In the experiment, a platinum tube was used as the experimental tube (d = 1.0–2.0 mm) to conduct joule heating by direct current. The distilled and deionized water was pressured by the pressurizer. The heat generation rate of the tube was controlled with the exponential function to obtain the transient heat transfer characteristics from the non-boiling region. The surface superheat increased as the heat flux increased in the experiment. The numerical simulation predicted the experimental data well. When the heat flux of the experiment was reached to the CHF point, the predicted value of heat transfer coefficient was approximately 3.5 % lower than that of the experiment.
Non-Newtonian Droplet Generation in a Flow-Focusing Microchannel
Authors: Xue C. D. , Sun Z. P. , Li Y. J. , Qin K. R.
Published: December 2019

The emergence of microfluidic droplets offers new opportunities to advance biomedical engineering, food production, and energy storage applications. These applications always involve complex fluids exhibiting obvious non-Newtonian behavior. Droplet generation has been extensively addressed, while the complete understanding of droplet generation in non-Newtonian fluid system is still nascent. Here, we present the study of non-Newtonian droplet generation in a flow-focusing microchannel. Polyethylene oxide aqueous solutions are used as the dispersed phase, while olive oil serves as the continuous phase to induce the generation. The molecular weight of polymer is constant while the concentrations are varied from dilute to semi-dilute regimes that are rarely explored in existing studies. The main features of non-Newtonian droplet generation are first identified, after which the concentration-dependent dripping to jetting transitions are clarified. The effects of shear thinning and elasticity on droplet generation are then separately investigated. We finally propose a scaling relation to predict the primary droplet size with the satellite droplets neglected. These results can not only extend the fundamental theory of droplet microfluidics but also facilitate the practical applications.
Numerical Study on the Mechanism of Heat Transfer Enhancement in Fe3O4 Nanoferrofluids With Magnetic Field
Authors: Wang Chenfei , Gao Dongdong , Bai Minli , Wang Peng , Li Yubai
Published: December 2019

Nanofluids is reported to significantly enhance heat transfer but with little cost of pressure loss. To further the enhancement of heat transfer using Fe3O4 nanofluids, a magnetic field is employed to control the trajectory of Fe3O4 nanoparticles. A numerical study is conducted with commercial soft ANSYS FLUENT and the simulations are done with a two-phase flow approach named Euler-Lagrange. By comparing heat transfer of laminar flow in a horizontal tube with magnetic field or not, various volume fraction (0.5%/2%) and Reynolds numbers (Re = 200–1000) are considered. Results show that magnetic field contributes an average 4% promotion in convective heat transfer coefficients compared with the condition of no magnet. The mechanism of the enhancement of heat transfer with magnetic field is explored based on the analysis of velocity field. Fe3O4 Nanoparticles move up and down under the magnetic force, and convective heat transfer is enhanced because of the disturbance of the Fe3O4 nanoparticles. Slip flow between the base fluid and nanoparticles also contributes to the enhancement of heat transfer.
Laser Ablation of Crystalline Material With and Without Water on Material Surface
Authors: Yao Wenlong , Yan Li , Qi Yunshu , Mei Ning
Published: December 2019

The phase and morphological changes of crystalline material during laser internal ablation with and without water on the material surface are studied using molecular dynamics simulations. The atomic image of the material morphology was obtained by recording the velocity and position variation of atoms. Temperature distribution contour of the crystalline material along the ablation process are charted by statistical physics method. Furthermore, density variation and phase variation contour of water are also charted. The results suggest that: First, during the ablation process of crystalline materials, energy transfer occurs between water and crystalline materials. Supercritical water is formed first, which restrains the sputtering of crystalline materials due to phase explosion and puts off the sputtering. Then the physical state of water changes from liquid to gaseous. Second, with water on the surface, the cavity shape is different from that without water, the width of upper part of cavity is decreased. Third, the volume of the cavity is affected by the thickness of the water layer.
Energy Harvesting Performance of Vertically Staggered Rectangle-Through-Holes Cantilevered in Piezoelectric Vibration Energy Harvester
Authors: Gao Shan , Ao Hongrui , Jiang Hongyuan
Published: December 2019

Piezoelectric vibration energy harvesting technology has attracted significant attention for its applications in integrated circuits, microelectronic devices and wireless sensors due to high power density, easy integration, simple configuration and other outstanding features. Among piezoelectric vibration energy harvesting structures, cantilevered beam is one of the simplest and most commonly used structures. In this work, a vertically staggered rectangle-through-holes (VS-RTH) cantilevered model of mesoscale piezoelectric energy harvester is proposed, which focuses on the multi-directional vibration collection and low resonant frequency. To verify the output performances of the device, this paper employs basic materials and fabrication methods with mathematical modeling. The simulations are conducted through finite element methods to discuss the properties of VS-RTH energy harvester on resonant frequency and output characteristics. Besides, an energy storage circuit with high power collection rate is adopted as collection system. This harvester is beneficial to the further application of devices working with continuous vibrations and low power requirements.
Near Field Radiative Heat Transfer in a Chain of Metallic Particles
Authors: Luo M. G. , Zhao J. M. , Liu L. H.
Published: December 2019

Heat transport mediated by near-field interaction in particulate system (e.g. chain of particles) is one of the research focuses in thermal transport in micro-nanoscale. Near field radiative heat transfer (NFRHT) characteristics of metallic nanoparticle chains (separation distance between neighboring particles is h) are analyzed by means of both coupled electric-magnetic dipole approximation and quadrupole approximation. Thermal conductance (G) between the central particle and other particle with different separation gaps (Δx) is calculated at both 300K and 1200K. Corrected polarizability is used to take quadrupole effect into consideration when calculating the NFRHT in extreme near field where dipole approximation ceases to be valid. Temperature distributions along several different chains of particles due to NFRHT are also predicted. Results show that, according to the asymptotic behavior of distribution of G along metallic chains similar as that observed in SiC chains, heat super-diffusion is demonstrated at both 300K and 1200K in metallic nanoparticle chains. At 300K, the contribution of quadrupole results in that thermal conductance responses to h in different way in metallic and dielectric particle chains. Temperature distribution and heat flow are the two key parameters used to characterize the heat transport in chains of particles. Ag particles in SiC chain act as barriers during the radiative heat transport process. Heat super-diffusion, as well as some other characteristics of NFRHT, observed in metallic nanoparticle chains may help for insight of heat transport in particulate system and new design of device in micro-nanoscale.
PETE Faculty Preferences and Responsibilities for Research, Teaching, and Service in the United States
Authors: Graber Kim C. , Richards K. Andrew R. , Killian Chad M. , Woods Amelia Mays
Published: December 2019

Purpose: Grounded in occupational socialization theory, the purpose of this investigation was to examine U.S. physical education teacher education faculty members’ work role preferences, how their actual work role responsibilities compare to institutional expectations, and differences in these preferences and responsibilities based on gender and institution type (i.e., bachelor’s, master’s, and doctoral institutions). Methods: Participants included 323 physical education teacher education faculty members (188 females and 135 males) from 230 institutions of higher education who completed an online survey. Data were analyzed using descriptive statistics and a series of 3 × 2 (Institution Type × Gender) factorial analysis of variances. Results: There was relative alignment between what faculty members are expected to do, what they prefer to do, and how they actually spend their time. There are, however, some important differences based on gender and institutional classification. Discussion/Conclusion: Results are discussed within the framework of occupational socialization theory and with reference to faculty role expectations and the propensity for role conflict.
Expression of 9-
O
- and 7,9-
O
-Acetyl Modified Sialic Acid in Cells and Their Effects on Influenza Viruses
Authors: Barnard Karen N. , Wasik Brian R. , LaClair Justin R. , Buchholz David W. , Weichert Wendy S. , Alford-Lawrence Brynn K. , Aguilar Hector C. , Parrish Colin R.
Published: December 2019

Sialic acids are key glycans that are involved in many different normal cellular functions, as well as being receptors for many pathogens. However, Sia come in diverse chemically modified forms. Here, we examined and manipulated the expression of 7,9-
O
- and 9-
O
-acetyl modified Sia on cells commonly used in influenza virus and other research by engineering the enzymes that produce or remove the acetyl groups.
Timing of Calorie Restriction in Mice Impacts Host Metabolic Phenotype with Correlative Changes in Gut Microbiota
Authors: Zhang Liying , Xue Xinhe , Zhai Rui , Yang Xin , Li Hui , Zhao Liping , Zhang Chenhong
Published: December 2019

Aberrant feeding patterns whereby people eat more frequently throughout the day and with a bias toward late-night eating are prevalent in society today. However, whether restriction of food to daytime in comparison to nighttime, coupled with restricted calorie intake, can influence gut microbiota, metabolism, and overall health requires further investigation. We surveyed the effects of the shift in feeding time on gut microbiota and metabolic phenotype in calorie-restricted mice and found that avoiding eating during the rest period may generate more beneficial effects in mice. This work strengthens the evidence for using “when to eat” as an intervention to improve health during calorie restriction.
Paramedic attitudes and experiences of enrolling patients into the PARAMEDIC-2 adrenaline trial: a qualitative survey within the London Ambulance Service
Authors: Lazarus Johanna , Iyer Rajeshwari , Fothergill Rachael T
Published: December 2019

Objectives

The aim of this study was to gather the views and experiences of paramedics who participated in a large-scale randomised controlled drug trial and to identify barriers to recruitment.

Design

We surveyed paramedics using a questionnaire consisting of a mix of closed and open ended questions.

Setting

The study was conducted within the London Ambulance Service, London, UK.

Participants

150 paramedics who were trained to enrol patients into the PARAMEDIC-2 randomised controlled trial of adrenaline versus placebo in out-of-hospital cardiac arrest and who returned the questionnaire.

Results

98% of study participants felt prehospital research was very important, and 97.3% reported an overall positive experience of being involved in a drug trial. Only 5.3% felt uncomfortable enrolling patients into the trial without prior consent from the patient or a relative. Over one- third (39.3%) identified one or more barriers to patient recruitment, the most common being the attitudes of other staff.

Conclusion

We found a strong appetite for involvement in prehospital research among paramedics and an understanding of the importance of research that prevailed over the complexities of the trial. This is an important finding demonstrating that potentially ethically controversial research can be undertaken successfully by paramedics in the prehospital environment.
Evaluation and Research on Financial Competitiveness of Innovation-Driven Enterprises Based on Interval Data Mining
Authors: Lv Wenwen , Salam Zarina Abdul
Published: December 2019

By studying the issue of evaluating the financial competitiveness of innovation-driven enterprises, the author proposed a new financial competitiveness evaluation method based on interval data mining. First, in order to effectively utilize the evaluation information that is provided by experts, the author suggested that the 95% confidence interval of the expert group’s evaluation information should be used as the interval evaluation data. Hence, the uncertainty of the evaluation process was effectively reduced, and the reliability of the evaluation results was improved. Then, empirical analysis was conducted on the financial competitiveness of an innovation-driven enterprise and its competitors using the interval data as the mining object, and a financial competitiveness evaluation method was given. The financial competitiveness level of this innovation-driven enterprise was analyzed according to the influence factors and overall situations, and suggestions to improve the innovation-driven enterprise’s financial competitiveness were provided in a targeted way. Finally, a discussion was made on how to strengthen the financial competitiveness of the innovation-driven enterprise with respect to five aspects.
Explicit equations from orbit reduction: One and two stages
Authors: Díaz Viviana Alejandra , Zuccalli Marcela
Published: December 2019

It is known that orbit reduction can be performed in one or two stages and it has been proven that the two processes are symplectically equivalent. In the context of orbit reduction by one stage, we shall write an expression for the reduced two-form in the general case and obtain the equations of motion derived from this theory. Then we shall develop the same process in the case in which the symmetry group has a normal subgroup to get the reduced symplectic form by two stages and the consequent orbit reduced equations. In both cases, we shall illustrate the method with three physical examples.
Structure of Birkhoff center of c-semirings
Authors: Sarkar R. , Kar S. , Biswas B. , Purkait S.
Published: December 2019

In [Kar, Purkait and Sarkar, Birkhoff center of [Formula: see text]-semiring, Asian-Europ. J. Math. 12(1) (2019) 1950003, 11 pp.], Kar et al. introduced the notion of Birkhoff center of a [Formula: see text]-semiring and obtained some characterizations of this center. In this paper, we study different types of lattice structures of Birkhoff center of a [Formula: see text]-semiring. We also prove that if two [Formula: see text]-semirings are isomorphic, then their Birkhoff centers are isomorphic but the converse is not necessarily true.
Highly transparent and flexible graphitic C3N4 nanowire/PVA/PEDOT:PSS supercapacitors for transparent electronic devices
Authors: Li Jialun , Zhang Xueyu , Li Xuesong , Duan Lianfeng , Yang Xijia , Wang Liying , Lü Wei
Published: December 2019

To achieve reliable flexibility and acceptable transparency for integrated electronics, the power supply sources of these devices have to meet the requirement of flexibility and transparency. Herein, we developed a facile and non-toxic way to manufacture all-solid-state supercapacitors with high capacitive performance, transparency and flexibility. The as-prepared g-C3N4 nanowires are distributed in Polyvinyl Alcohol (PVA) and Poly(3,4-ethylenedioxythiophene)/poly(styrenesulfonate) (PEDOT:PSS) solution, transparent film could be formed by vacuum filtration. The g-C3N4 nanowires provide pseudocapacitance and PVA and PEDOT:PSS matrix provides bendable and stretchable ability. The g-C3N4/PVA electrode achieves a specific areal capacitance of 3.51[Formula: see text]mF[Formula: see text]cm[Formula: see text] with transparency of 85%, and that of g-C3N4/PVA/PEDOT:PSS is 5.32[Formula: see text]mF[Formula: see text]cm[Formula: see text] with transparency of 72%. The facile process provides a reasonable architecture for the preparation of a variety of flexible, transparent and wearable electronic devices. The flexible and transparent devices show an instant response to the finger bending with the capacitance change of more than 25%, which provides the possibility for fabricating smart flexible device to monitor human health and motion detection.
DOES THE BUSINESS CLIMATE AFFECT PRIVATE DOMESTIC AND FOREIGN INVESTMENT? EMPIRICAL EVIDENCE FROM THE MENA REGION
Authors: BEN-SALHA OUSAMA , ZMAMI MOURAD
Published: December 2019

The debate on the impact of business climate on private investment is still ongoing today. This paper contributes to the existing literature by examining the impact of a wide range of dimensions of the business climate on domestic investment and foreign direct investment in a sample of Middle East and North African economies between 2000 and 2015. Findings of the paper add new evidence and shed interesting insights into the debate. While almost all areas matter for domestic and foreign investors, the common and most important dimensions for both of them are regulations, macroeconomic management and infrastructure. Moreover, the control of corruption and labor market regulation are found to exert opposite effects on domestic investment and foreign direct investment. We conclude that setting up a good business climate is an overall process that should touch simultaneously and gradually all dimensions.
Influence of Parent Stressors on Adolescent Obesity in African American Youth
Authors: Allport Lauren , Song MinKyoung , Leung Cindy W. , McGlumphy Kellye C. , Hasson Rebecca E.
Published: December 2019

Objective. The purpose of this study was to examine the relationships between individual parent stressors (financial, legal, career, relationships, home safety, community safety, medical, housing, authority, and prejudice) and adolescent obesity in African American adolescents. Methods. Data were from a cross section convenience sample of 273 African American parent-child dyads (ages 11–19) from Washtenaw County, Michigan. A subset of 122 dyads who completed parent and child questionnaires were included in this analysis. Parent stressors were assessed using the Crisis in Family Systems Revised (CRISYS-R) questionnaire. Height, weight, and waist circumference were measured by trained staff; height and weight were converted to BMI. Multivariate linear regression models were used to examine the relationships between individual parent stressors and adolescent BMI and waist circumference. Results. Parental exposure to stressors related to safety in the community was positively associated with adolescent BMI (β = 1.20(0.47), p=0.01) and waist circumference (β = 2.86(1.18), p=0.02). Parental appraisal of stressors related to safety in the community as “difficult to get through” was positively associated with adolescent BMI (β = 0.39(0.14), p=0.006) and waist circumference (β = 1.00(0.35), p=0.005). These relationships remained significant when adjusting for behavioral and psychosocial covariates. There were no significant relationships observed between other parent stressors and adolescent BMI or waist circumference. Conclusion. These findings suggest parents’ exposure and appraisal of stressors related to community safety are associated with increased adolescent obesity in African American youth. Longitudinal, larger-scale studies are needed to better understand the mechanisms by which community safety may increase obesity risk in this ethnic minority pediatric population. This trail is registered with NCT02938663.
Dysregulation of Kisspeptin and Leptin, as Anorexigenic Agents, Plays Role in the Development of Obesity in Postmenopausal Women
Authors: Hestiantoro Andon , Astuti Brilliant P. K. , Muharam Raden , Pratama Gita , Witjaksono Fiastuti , Wiweko Budi
Published: December 2019

During the menopausal period, women have a higher tendency to develop obesity and any other metabolic syndromes. Dysregulation of leptin and kisspeptin signaling as anorexigenic agents is believed to be the connection between metabolic disorders and altered reproductive function. Therefore, this study aimed at investigating the association between leptin, soluble leptin receptor (sOBR), free leptin index, kisspeptin concentrations, and body mass index (BMI) in postmenopausal women. A cross-sectional study was carried out among 171 postmenopausal women aged 40–75 years from 2017 to 2018. Subjects were assigned into 2 groups according to their BMIs: obese group (84 subjects) and nonobese group (87 subjects). In addition to anthropometric measurement, blood sample was collected from each subject for leptin, sOBR, free leptin index (FLI), and kisspeptin evaluation. Bivariate and correlation analysis discovered that leptin and FLI were positively correlated with BMI, while sOBR and kisspeptin were negatively correlated with BMI. Among those variables, multivariate analysis found that leptin, sOBR, and kisspeptin were independently associated with obesity. Therefore, it can be concluded that higher serum leptin concentration and FLI, as well as lower serum sOBR and kisspeptin concentrations, are significantly associated with obesity in postmenopausal women.
Development and Implementation of Short Courses to Support the Establishment of a Prehospital System in Sub-Saharan Africa: Lessons Learned from Tanzania
Authors: Sawe Hendry R. , Mfinanga Juma A. , Kisakeni Samwel , Shao Patrick , Nkondora Paulina , White Libby , Bollinger Christina , Kulola Irene B. , George Upendo N. , Runyon Michael S. , Noste Erin
Published: December 2019

Background. Tanzania has no formal prehospital system. The Tanzania Ministry of Health launched a formal prehospital system to address this gap. The Muhimbili University of Health and Allied Sciences (MUHAS) was tasked by the Ministry of Health to develop and implement a multicadre/provider prehospital curriculum so as to produce necessary healthcare providers to support the prehospital system. We aim to describe the process of designing and implementing the multicadre/provider prehospital short courses. The lessons learned can help inform similar initiatives in low- and middle-income countries. Methods. MUHAS collaborated with local and international Emergency Medicine and Emergency Medical Services (EMS) specialists to form the Emergency Medical Systems Team (EMST) that developed and implemented four short courses on prehospital care. The EMST used a six-step approach to develop and implement the curriculum: problem identification, general needs assessment, targeted needs assessment, goals and objectives, educational strategies, and implementation. The EMST modified current best EMS practices, protocols, and curricula to be context and resource appropriate in Tanzania. Results. We developed four prehospital short courses: Basic Ambulance Provider (BAP), Basic Ambulance Attendant (BAAT), Community First Aid (CFA), and EMS Dispatcher courses. The curriculum was vetted and approved by MUHAS, and courses were launched in November 2018. By the end of July 2019, a total of 63 BAPs, 104 BAATs, 25 EMS Dispatchers, and 287 CFAs had graduated from the programs. The main lessons learned are the importance of a practical approach to EMS development and working with the existing government cadre/provider scheme to ensure sustainability of the project; clearly defining scope of practice of EMS providers before curriculum development; and concurrent development of a multicadre/provider curriculum to better address the logistical barriers of implementation. Conclusion. We have provided an overview of the process of designing and implementing four short courses to train multiple cadres/providers of prehospital system providers in Tanzania. We believe this model of curricula development and implementation can be replicated in other countries across Africa.
Polystyrene Microsphere Optical Properties by Kubelka–Munk and Diffusion Approximation with a Single Integrating Sphere System: A Comparative Study
Authors: Shahin Ali , Bachir Wesam , Sayem El-Daher Moustafa
Published: December 2019

The optical properties of 1 μm polystyrene in the wavelength range of 500–750 nm were estimated by using a white light spectrophotometric transmittance spectroscopy and a single integrating sphere system. To retrieve the optical characteristics, two analytical methods, namely, diffusion approximation and Kubelka–Munk were used, and then their results were compared with Mie theory calculations. The correspondence of the Kubelka–Munk scattering coefficient with Mie was obvious, and relative errors varied between 6.73% and 2.66% whereas errors varied between 6.87% and 3.62% for diffusion theory. Both analytical methods demonstrated the absorption property of polystyrene over the abovementioned wavelength range. Although absorption coefficient turned out to be much lower than scattering, constructing a realistic optical phantom requires taking into account absorption property of polystyrene. Complex refractive index of polystyrene based on these two methods was determined. Inverse Mie algorithm with scattering coefficient was also used to retrieve the real part of refractive index and absorption coefficient for calculating the imaginary part of refractive index. The relative errors of the real part did not exceed 2.6%, and the imaginary part was in consistence with the prior works. Finally, the presented results confirm the validity of diffusion theory with a single integrating sphere system.
Centrality Dependence of Multiplicity Fluctuations in Ion-Ion Collisions from the Beam Energy Scan at FAIR
Authors: Chandra Anuj , Ali Bushra , Ahmad Shakeel
Published: December 2019

Multiplicity distributions and event-by-event multiplicity fluctuations in AuAu collisions at energies in future heavy-ion experiment at the Facility for Anti-proton and Ion Research (FAIR) are investigated. Events corresponding to FAIR energies are simulated in the frame work of Ultra Relativistic Quantum Molecular Dynamics (URQMD) model. It is observed that the mean and the width of multiplicity distributions monotonically increase with beam energy. The trend of variations of dispersion with mean number of participating nucleons for the centrality-bin width of 5% are in accord with the Central Limit Theorem. The multiplicity distributions in various centrality bins as well as for full event samples are observed to obey Koba, Nielsen and Olesen (KNO) scaling. The trends of variations of scaled variance with beam energy are also found to support the KNO scaling predictions for larger collision centrality. The findings also reveal that the statistical fluctuations in 5% centrality-bin width appear to be under control.
Risk Factors and Changes of Peripheral NK and T Cells in Pulmonary Interstitial Fibrosis of Patients with Rheumatoid Arthritis
Authors: Lai Na-Lin , Jia Wen , Wang Xia , Luo Jing , Liu Guang-Ying , Gao Chong , Li Xiao-Feng , Xie Jian-Fang
Published: December 2019

Objective. The absolute and relative changes of peripheral NK and T subsets are unclear in rheumatoid arthritis (RA) associated with pulmonary interstitial fibrosis (RA-ILD). To investigate the clinical risk factors, especially the changes of lymphocyte subsets, in RA-ILD in order to make early diagnosis and achieve prevention of the pulmonary interstitial lesions. Methods. A total of 100 RA and 100 RA-ILD patients were enrolled. Rheumatoid factor, anti-cyclic citrulline peptide antibody, erythrocyte sedimentation rate, immunoglobulin, and C-reactive protein were examined. The percentage and absolute number of NK, T, B, Treg, Th1, Th2, and Th17 cells in peripheral blood were determined by flow cytometry. Results. RA-ILD is more common in older and male RA patients and/or those with higher autoantibody titers. Flow cytometry showed that the absolute and relative numbers of CD56+ NK cells were significantly higher in RA-ILD (280.40 ± 180.51 cells/μl vs. 207.66 ± 148.57 cells/μl; 16.62 ± 8.56% vs. 12.11 ± 6.47%), whereas the proportion of T cells and CD4+ T cells was lower in peripheral blood of RA-ILD patients (69.82 ± 9.30%; 39.44 ± 9.87 cells/μl) than that in RA patients (74.45 ± 8.72%; 43.29 ± 9.10 cells/μl). Conclusions. The occurrence of RA-ILD is closely related to the older male patients with high titer of various self-antibodies. Imbalance of CD3−CD56+ NK cells and T cells with other subsets were found in RA-ILD patients, which, together with older age, male, and high levels of autoantibodies should be considered as risk factors of pulmonary interstitial lesions.
Characterising SRD5A2 Gene Variants in 37 Indonesian Patients with 5-Alpha-Reductase Type 2 Deficiency
Authors: Marzuki Nanis S. , Idris Firman P. , Kartapradja Hannie D. , Harahap Alida R. , Batubara Jose R. L.
Published: December 2019

The 5-alpha-reductase type 2 deficiency (5ARD2) is an autosomal recessive condition associated with impairment in the conversion of testosterone to dihydrotestosterone. This condition leads to undervirilisation in 46,XY individuals. To date, there have been more than 100 variations identified in the gene responsible for 5ARD2 development (steroid 5-alpha-reductase 2, SRD5A2). However, few studies have examined the molecular characterisation of Indonesian 5ARD2 cases. In the current study, we analysed 37 subjects diagnosed with 46,XY DSD (disorders of sex development) with confirmed variations in the SRD5A2 gene. We examined results from testosterone/dihydrotestosterone (T/DHT) and urinary etiocholanolone/androsterone (Et/An) ratios, as well as from molecular and clinical analyses. Twelve variants in the SRD5A2 gene were identified, and 6 of which were novel, namely, c.34–38delGinsCCAGC, p.Arg50His, p.Tyr136∗, p.Gly191Arg, p.Phe194Ile, and p.Ile253Val variants. Moreover, we determined that 20 individuals contained harmful mutations, while the remaining 17 variants were benign. Those containing harmful mutations exhibited more severe phenotypes with median external genitalia masculinisation scores (EMS) of 3 (1.5–9) and were more likely to be diagnosed at a later age, reared as female, and virilised at pubertal age. In addition, the respective sensitivities for detecting severe 5ARD2 cases using T/DHT (cutoff: 10) and urinary Et/An ratios (cutoff: 0.95) were 85% and 90%, whereas mild cases were only identified with 64.7% and 47.1% sensitivity, respectively. Although we were unable to identify clear correlations between genotypic and phenotypic characteristics in this study, we clearly showed that individuals who were homozygous or compound heterozygous for any of the harmful mutations were more likely to exhibit classic 5ARD2 phenotypes, lower EMS, female assignment at birth, and virilisation during puberty. These results serve to inform the development of improved clinical and molecular 5ARD2 diagnostic approaches, specifically in Indonesian patients.
Profile-Tracking-Based Adaptive Guidance Law against Maneuvering Targets
Authors: Huang Jingshuai , Zhang Hongbo , Tang Guojian , Bao Weimin
Published: December 2019

For the terminal guidance problem of a missile intercepting a maneuvering target, a profile-tracking-based adaptive guidance law is proposed with inherent continuity in this paper. To flexibly and quantitatively control the convergence rate of the line-of-sight rate, a standard tracking profile is designed where the convergence rate is analytically given. Then, a nonsingular fast terminal sliding-mode control approach is used to track the profile. By estimating the square of the upper bound of target maneuver, an adaptive term is constructed to compensate the maneuver. Therefore, no information of target acceleration is required in the derived law. Stability analysis shows that the tracking error can converge to a small neighborhood of zero in finite time. Furthermore, a guidance-command-conversion scheme is presented to convert the law into the one appropriate for endoatmospheric interceptions. Simulation results indicate that the proposed law is effective and outperforms existing guidance laws.
The Application of Green-Synthesis-Derived Carbon Quantum Dots to Bioimaging and the Analysis of Mercury(II)
Authors: Zhang Qianchun , Zhang Xiaolan , Bao Linchun , Wu Yun , Jiang Li , Zheng Yuguo , Wang Yuan , Chen Yafei
Published: December 2019

Ginkgo leaves were used as precursors for the hydrothermal synthesis of carbon quantum dots (CQDs), which were subsequently characterized by transmission electron microscopy as well as Fourier-transform infrared, X-ray powder diffraction, and X-ray photoelectron spectroscopy. The prepared CQDs exhibited a fluorescence quantum yield of 11% and superior water solubility and fluorescence stability, as well as low cytotoxicities and excellent biocompatibilities with A549 and HeLa cells; these CQDs were also used to bioimage HeLa cells. Moreover, owing to the experimental observation that Hg2+ quenches the fluorescence of the CQDs in a specific and sensitive manner, we developed a method for the detection of Hg2+ using this fluorescence sensor. The sensor exhibited a linear range for Hg2+ of 0.50–20 μM, with an excellent coefficient of determination (R2 = 0.9966) and limit of detection (12.4 nM). In practice, the proposed method was shown to be highly selective and sensitive for the monitoring of Hg2+ in lake water and serum samples.
Health Care Professionals’ Knowledge, Attitude, and Practice towards Adverse Drug Reaction Reporting and Associated Factors at Selected Public Hospitals in Northeast Ethiopia: A Cross-Sectional Study
Authors: Kassa Alemu Belete , Biru Tessema Tsehay
Published: December 2019

Background. The role of health care professionals among other stakeholders in early detection, assessment, documentation, and reporting as well as preventing suspected adverse reactions is very crucial to mitigate drug-related problems in health facilities. Previous reports from literatures have indicated that adverse drug reaction reporting is highly linked to the knowledge and attitude of the health care professionals. Objective. To assess knowledge, attitude, and practice of health care professionals about adverse drug reactions and the associated factors at selected public hospitals in Northeast Ethiopia. Methods. A hospital-based quantitative cross-sectional study design was employed. A structured self-administered questionnaire was used to collect data on KAP of selected health care providers by the convenience sampling method. Data were entered into Epi info version 3.5.3 and analyzed using SPSS Version 20. Association between dependent and independent variables was found by using bivariate and multivariate logistic regression analysis where p<0.05 was considered to be statistically significant. Results. Out of 120 questionnaires distributed, 114 respondents filled and returned, giving a 95% response rate. From total, 49 (43%) were nurses, 26 (22.8%) physicians, 17 (14.9%) pharmacy professionals, 12 (10.5%) health officers, and 10 (8.8%) midwives. About 86 (75.44%) study participants had an inadequate knowledge towards ADR reporting, and half of participants failed to report the adverse drug reactions they encountered. But the majority of participants (84, 73.68%) had a favorable attitude towards ADR reporting. Nurses [AOR = 0.069, 95% CI (0.018–0.275)], health officers [AOR = 0.10, 95% CI (0.015–0.647)], and physicians [AOR = 0.14, 95% CI (0.03–0.64)] were found to be less likely to have adequate knowledge on ADR reporting compared to pharmacy professionals. Conclusion. Even though the majority of health care professionals had a positive attitude, they had inadequate knowledge and poor practice towards ADR reporting.
Clonal Selection Drives NF-κB Activation in Recurrent Nasopharyngeal Carcinoma
Authors: Sehgal Kartik , Barbie David A.
Published: December 2019

Cancer genomic profiling has improved our understanding of the key drivers of tumor development, clonal evolution, and recurrence, and aided precision medicine efforts to eradicate therapy-resistant cancer cell clones. In this issue, You and colleagues report these results for recurrent nasopharyngeal carcinoma, an aggressive malignancy associated with poor outcomes with recurrent disease. They identify a crucial contributory role of clonal NF-κB activating mutations in pathogenesis of recurrence in this cancer and provide a promising target for combinatorial therapeutic approaches.

See related article by You et al., p. 5930
Thickness of the Lamina Cribrosa, Retinal-Nerve Fiber Layer, and Peripapillary Choroid in Patients with Branch Retinal Vein Occlusion
Authors: Sirakaya Ender , Kucuk Bekir
Published: December 2019

Purpose: To compare the thickness of the lamina cribrosa (LC), retinal-nerve fiber layer (RNFL), and peripapillary choroid (PC) in patients with unilateral branch retinal-vein occlusion (BRVO) and healthy individuals. Methods: The 70 eyes of 35 patients with unilateral BRVO, grouped as either affected or unaffected, and 38 right eyes of 38 healthy individuals were examined for LC, RNFL, PC thickness, and LC depth with spectral-domain optical coherence tomography. Results: The unaffected eyes of patients with BRVO had a significantly thinner RNFL on average and in the inferior quadrant than the eyes of healthy controls. Mean LC thickness in BRVO-affected and BRVO-unaffected eyes was significantly thinner than in controls, and mean LC depth was significantly deeper as well. The average, superior, and inferior PC thickness in both BRVO-affected and BRVO-unaffected eyes and nasal PC thickness in the BRVO-affected eyes were significantly thinner than in the eyes of controls. Conclusion: Thinner LCs and PCs in both eyes of patients with unilateral BRVO and thinner RNFLs in BRVO-unaffected eyes than in the eyes of healthy controls suggest that BRVO and glaucoma have underlying pathological mechanisms and risk factors in common that lead to their development.
ЛЕТКІ ЖИРНІ КИСЛОТИ ЯК МЕТАБОЛІЧНІ МАРКЕРИ ПОРУШЕННЯ МІКРОБІОЦЕНОЗУ КИШЕЧНИКУ ПРИ РОТАВІРУСНІЙ ІНФЕКЦІЇ У ДІТЕЙ
Authors: Nezhoda I. I. , Naumenko O. M. , Nikulchenko O. V.
Published: December 2019

Мета дослідження – вивчити стан метаболічної активності кишкової мікрофлори у дітей, хворих на ротавірусну інфекцію (РВІ), шляхом оцінки рівня та спектру летких жирних кислот (ЛЖК) у динаміці хвороби залежно від ступеня тяжкості та віку.

Пацієнти і методи. Під спостереженням перебувало 64 дитини раннього віку, середній вік яких становив (18,5±1,2) міс., основну групу склали хворі на ротавірусну інфекцію (n=31), контрольну (n=33) – здорові діти, порівнювані за віком та статтю. Для визначення метаболічної активності мікрофлори та оцінки метаболічно-енергетичних процесів у просвіті кишечнику були вивчені основні активні метаболіти – леткі жирні кислоти: масляна, пропіонова та валеріанова кислоти за допомогою газово-рідинної хроматографії випорожнень, на початку захворювання (1-2-а доба хвороби) та в динаміці – на 5-6-й день лікування.

Газово-рідинна хроматографія випорожнень виконувалась на основі розрахунку внутрішнього стандарту, що передбачає додавання до певної маси досліджуваного зразка речовини з відомою масою і площею піка.

Результати. У дітей основної групи був знижений як загальний рівень ЛЖК, так і вміст окремих жирних кислот, тобто мало місце виснаження сумарного пулу мікробних метаболітів. У здорових дітей загальний рівень ЛЖК становив (0,803±0,340) мг/мл, а у дітей з РВІ – 0,048±0,008 мг/мл (Р<0,05). Абсолютні концентрації масляної кислоти у копрофільтратах хворих дітей були значно знижені – (0,017±0,005) проти (0,69±0,33) мг/мл у здорових дітей (Р<0,05); кон­центрація пропіонової кислоти становила (0,0267±0,006) мг/мл, а в дітей контрольної групи –(0,640±0,020) мг/мл (Р<0,001). Ці зміни свідчать про зміну метаболізму на рівні слизової оболонки кишечнику у вигляді порушення мікроциркуляції та трофічних процесів. У процесі лікування (на 5-6-у добу) кон­центрація ЛЖК достовірно зросла і становила (0,082±0,0064) мг/мл, (Р<0,05), що є гарною прогностичною ознакою відновлення нормальних метаболічних процесів у кишечнику. Найнижчий рівень метаболітів був зафіксований при середньому ступеню тяжкості РВІ і становив (0,038±0,008) мг/мл, причому він був нижчим порівняно зі здоровими дітьми (Р<0,05). Загальний рівень ЛЖК у дітей першого року життя становив (0,045±0,0078) і був нижчим, ніж у дітей старше 1 року, в яких досягав (0,058±0,025) мг/мл, причому у всіх дітей загальний рівень ЛЖК був нижчий, ніж у здорових – (0,803±0,340) мг/мл (Р<0,05).

Висновки. При РВІ у хворих значно пригнічується активність кишкової мікрофлори, що характеризується вірогідним зниженням як сумарної концентрації ЛЖК – (0,048±0,008) мг/мл порівняно зі здоровими дітьми – (0,803±0,34) мг/мл при Р<0,01, так і концентрацій окремих кислот: масляної – (0,017±0,005) мг/мл, пропіонової – (0,0267±0,006) мг/мл та валеріанової – (0,041±0,007) мг/мл порівняно зі здоровими дітьми (Р<0,01), що свідчить про порушення метаболічних процесів на рівні колоноцитів.
Criando dificuldades para vender facilidades: corrupção, burocracia e crescimento corporativo no Mercosul
Authors: Lima Lauro Vinício de Almeida , Rufino Maria Audenora , Machado Márcia Reis
Published: December 2019

A pesquisa teve como escopo investigar, nos países do Mercosul, o reflexo da sinergia entre a dificuldade de realização de negócios e a percepção da corrupção do setor público no crescimento econômico e financeiro das empresas. A amostra foi composta por 8 países integrantes do Mercosul, entre os anos de 2010 a 2017, com um total de 655 empresas de diversos setores e 4.648 observações. Com base na Teoria da Graxa sobre Rodas, o estudo levou em consideração que a corrupção pode favorecer o crescimento econômico das empresas, à medida que desate as amarras da burocracia e reduza os custos transacionais das empresas. Os resultados encontrados conduzem ao entendimento de que a associação sinérgica entre a percepção da corrupção e a dificuldade de realizações de negócios nos países do Mercosul favorece o crescimento econômico das empresas em tais países. O efeito sinérgico positivo é direcionado, preponderantemente, para as grandes empresas, em função de maiores condições financeiras de arcar com os custos da corrupção. As evidências empíricas encontradas acrescentam novas centelhas para o constructo argumentativo no qual se pauta a Teoria da Graxa sobre Rodas.
Corrupção, lavagem de dinheiro e conluio no Brasil: evidências empíricas dos vínculos entre fraudadores e cofraudadores no caso Lava Jato
Authors: Maragno Lucas Martins Dias , Knupp Paulo de Souza , Borba José Alonso
Published: December 2019

Este estudo exploratório objetiva compreender os vínculos que conectam cofraudadores em esquemas de corrupção e lavagem de dinheiro presentes na Operação “Lava Jato”. A base de dados foi construída por meio da leitura das denúncias realizadas e documentadas pelo Ministério Público Federal (MPF). Foram identificadas todas as pessoas acusadas pelo MPF e suas características (gênero, idade e experiência anterior ao crime), assim como a natureza dos vínculos entre fraudadores e cofraudadores, o tipo de crime e o papel do acusado no crime. Sinteticamente, os resultados demonstraram que os fraudadores líderes já haviam sido condenados anteriormente e/ou possuíam experiência nas fraudes cometidas. Os resultados demonstraram ainda que os vínculos afetivos estão positivamente relacionados à apropriação indébita, ocultação de provas e “testa de ferro”. Se por um lado, Fee e Murphy (2015) destacaram a natureza dos vínculos entre membros de grupos fraudulentos, nossos achados evoluem e fornecem algumas evidências empíricas dos vínculos funcionais que servem à organização e invariavelmente para os vínculos afetivos.