bluuebunny/crossref_metadata_2025_split huggingface dataset:
Large scale production of superparamagnetic iron oxide nanoparticles by the haloarchaeon Halobiforma sp. N1 and their potential in localized hyperthermia cancer therapy
Authors: Salem Nayera F A , Abouelkheir Samia S , Yousif Asmaa M , Meneses-Brassea Bianca P , Sabry Soraya A , Ghozlan Hanan A , El-Gendy Ahmed A 
Published: November 2020

Abstract
Magnetic iron oxide nanoparticles are among metal nanoparticles that attract huge attention in many biotechnological fields especially in the biomedical area. Their extensive capabilities and easy separation methodology drive them to be an interesting point to many researchers. Biosynthesis is of a major importance among different methods of nanoparticles production. Microbial synthesis of these nanoparticles by bacteria and yeasts have been reported on a wide scale. However, biosynthesis using halophilic archaea is still in an early stage. This study reveals the first contribution of the haloarchaeon Halobiforma sp. N1 to the nanobiotechnology field. It reports a rapid and economical one-step method of fabricating functionalized superparamagnetic iron oxide nanoparticles and their feasibility for hyperthermia treatment for cancer therapy. Herein, we have focused on optimizing the quantity of these fascinating nanoparticles, obtaining a very high yield of 15 g l−1 with high dispersion in water solution. Their unique characteristics enable them to participate in medical applications. They are nearly spherical in shape with a high degree of homogenity and uniformity with average diameter of 25 ± 9 nm. Also, the magnetic properties and elemental structure of the formed nanoparticles tend to be superparamagnetic like behavior with saturation magnetization of 62 emu g−1 and purity of 98.38% of iron oxide, respectively. The specific absorption rate (SAR) was measured and the particles induced significant heating power at lower frequencies which is a promising result to be applied for in vitro/in vivo hyperthermia studies in the near future.
Decoupling ion energy and flux in intermediate pressure capacitively coupled plasmas via tailored voltage waveforms
Authors: Doyle Scott J , Gibson Andrew R , Boswell Rod W , Charles Christine , Dedrick James P 
Published: November 2020

Abstract
The discrete control of ion energy and flux is of increasing importance to industrially relevant plasma sources. The ion energy distribution functions (IEDFs) and net ion flux incident upon material surfaces in intermediate pressure (≈133 Pa, 1 Torr) radio-frequency capacitively coupled plasmas (rf CCPs) are coupled to the spatio-temporal sheath dynamics and resulting phase-averaged sheath potential. For single frequency driven discharges this co-dependence of ion energy and flux on the sheath potential limits the range of accessible operating regimes. In this work, experimentally benchmarked 2D fluid/Monte-Carlo simulations are employed to demonstrate quasi-independent control of the ion flux and IEDF incident upon plasma facing surfaces in a collisional (≈200 Pa, 1.5 Torr argon) rf hollow cathode discharge driven by multi-harmonic (n ⩾ 2) tailored voltage waveforms. The application of variable phase offset n = 5 tailored voltage waveforms affords a significant degree of control over the ion flux

Γ

A
r

+

and mean ion energy

ϵ

̂

A
r

+

, modulating each by factors of 2.9 and 1.6, respectively as compared to 1.8 and 1.6, achieved via n = 2 dual-frequency voltage waveforms. The disparate modulations achieved employing n = 5 tailored voltage waveforms demonstrate a significant degree of independent control over the mean ion energy and ion flux for collisional conditions, enabling access to a wider range of operational regimes. Maximising the extent to which ion energy and flux may be independently controlled enables improvements to plasma sources for technological applications such as plasma assisted material manufacture and spacecraft propulsion.
Propagation of positive discharges in an air bubble having an embedded water droplet
Authors: Ning Wenjun , Lai Janis , Kruszelnicki Juliusz , Foster John E , Dai Dong , Kushner Mark J 
Published: November 2020

Abstract
Low temperature plasmas generated inside gas bubbles immersed in water is an effective method of rapidly transferring plasma generated reactive species to the water for applications in biomedicine, agriculture and environment. Reactive species are generally produced in the gas phase plasma and then solvate into the liquid. The large surface-to-volume ratio (SVR) of the bubble accelerates this process. In generating bubbles in water, aerosols and droplets are also contained within the bubble. These droplets also have a large SVR and so can be rapidly plasma activated. However, the presence of the droplets can also impact the propagation of the plasma in the bubble. In this paper, results are discussed from computational and experimental investigations of the formation and evolution of discharges in an air bubble immersed in water with an embedded water droplet. The computations were performed with a two-dimensional plasma hydrodynamics model. Experiments were performed with a quasi-2D bubble apparatus. In bubbles having a droplet, a plasma filament typically bridges from the powered electrode to the droplet, and then from the droplet to the bubble surface. A surface-hugging streamer also occurs on the inner bubble surface and on the surface of the droplet. Both surface streamers result in part from surface charge accumulation and can dominate the formation of reactive species that transport into the droplet. Increasing droplet conductivity suppresses propagation of the surface discharge and leads to a lower density of aqueous reactive species. Increasing conductivity of the surrounding water does not change the overall structure of the discharge but does slightly elevate the discharge intensity. The size and shape of the embedded droplet can significantly affect the formation and propagation of the streamer.
Negative differential resistance characteristics of GaN-based resonant tunneling diodes with quaternary AlInGaN as barrier
Authors: Yang Wen-Lu , Yang Lin-An , Zhang Xiao-Yu , Li Yang , Ma Xiao-Hua , Hao Yue 
Published: November 2020

Abstract
AlInGaN lattice-matched to GaN is proposed as a barrier for double-barrier single quantum well structure resonant tunneling diodes (RTDs), and it achievesnearly strain-free RTD with low In composition and thereby relatively high manufacturability. Compared with the lattice-matched ternary Al0.83In0.17N/GaN RTD, three lattice-matched InAlGaN/GaN RTD samples exhibit peak current density J
P over 20 times larger than that of the lattice-matched ternary RTD in numerical simulations. Simultaneously, two shallow defect levels (E
1 = 0.351 eV, E
2 = 0.487 eV) are considered at the RTD heterointerface to reveal the I–V characteristics under different defect densities. Negative differential resistance characteristics of the three quaternary RTDs are still available even though the defect density is up to ∼1018 cm−3, while that of the lattice-matched ternary RTD almost disappears when the defect density is ∼1017 cm−3 as a result of the lager ionization rate. Further, we introduce a deep-level defect E
t = 1 eV at the heterointerface and perform multiple forward voltage sweeps. Simulations show that the quaternary RTD samples have better reproducibility in spite of the defect density being 100 times larger than that of the lattice-matched ternary RTD. This work illustrates that InAlGaN can provide greater flexibility for the design and fabrication of GaN-based RTDs.
A machine learning workflow for 4D printing: understand and predict morphing behaviors of printed active structures
Authors: Su Jheng-Wun , Li Dawei , Xie Yunchao , Zhou Thomas , Gao Wenxin , Deng Heng , Xin Ming , Lin Jian 
Published: November 2020

Abstract
Understanding and predicting morphing response of printed active structures remain a challenge in 4D printing. To tackle it, in this paper, we present a consolidated data-driven approach enabled by an ensemble of machine learning (ML) algorithms. First, three ML algorithms were employed to quantitatively correlate a geometrical feature (thickness) with the final morphing shapes indicated by curvatures and curving angles. Among them, the gradient boosting algorithm achieved correlation factors (R
2) of 0.96 and 0.94 when predicting the curvatures and curving angles by using the data collected from 150 experiments. The random forest model enabled to rank the importance of fabrication parameters in determining the shape morphing behaviors. To forecast the dynamic response of printed structures, three time series forecast algorithms were implemented based on the time-dependent image data during morphing processes of the printed active structures. Among them, the exponential smoothing method achieved an average mean absolute percentage error of 0.0139. This work offers a proof-of-concept on how the ensemble ML algorithms can be employed to delineate and predict morphing mechanism of printed active structures, thus providing a new paradigm for advancing the state-of-the-art research in 4D printing.
Effects of functional alkali in magnetorheological finishing fluid
Authors: Zhang Yunfei , Fang Fengzhou , Wang Lili , Li Xiaoyuan , Liu Jiabao , Ye Zuoyan , Tian Dong , Huang Wen , Yu Miao , Ye Minheng , Wang Chao 
Published: November 2020

AbstractMagnetorheological (MR) fluids can be utilized for ultra-precise finishing, for instance, in fused silica (FS) optics in giant laser system. However, few modification methods of MR fluid can improve the material removal rate (MRR) and surface quality of the finished optics simultaneously. In this study, we investigated the application of functional alkali additives in MR finishing fluid. MRR was doubled over the untreated MR fluid; meanwhile the surface roughness of the FS converged to 0.44 nm. Such excellent finishing performance can be mainly attributed to the dual functional effects of the triethanol amine (TEA) alkali, the hydroxides released by TEA contributes to the MRR increase and the steric hindrance effect of the ethanol ligands helps improve the surface quality.
Convergence to the traveling wave solution of a biological-physical model through a differential equation with piecewise constant argument
Authors: Ramirez-Carrasco C , Duque-Marín F 
Published: November 2020

Abstract
Getting to know explicitly or approximately the traveling wave solutions of the diffusive delay logistic equation, commonly known as the delayed Kolmogorov-Petrovsky-Piscounov-Fisher equation, is of major importance for understanding various biological and physical phenomena. In this study, we discretize the delay argument of the equation that satisfies the traveling wave and we obtain a second order delay differential equation with piecewise constant argument. We prove the existence and uniqueness of a solution for the discretized equation, and then prove that this solution converges uniformly along the whole straight towards the traveling wave. The methodology posed is based on the upper and lower solutions technique along with the use of a monotone integral operator. Our results show that the technique we developed is another good method for approaching traveling wave solutions. In addition, we suggest that this method can be applied to other reaction-diffusion equations that model a wide range of biological, physical, and chemical phenomena.
Writer verification based on simple graphemes and extreme learning machine approaches
Authors: Vásquez A , Mora M , Aubin V , Salazar E , Barrientos R , Hernandez R , Vilches K 
Published: November 2020

Abstract
mTraditional literature presents complex biometric sources, descriptors, and classifiers to solve the writer’s verification problem. The simple graphemes have been studied recently considering classifiers such as multilayer perceptron, support vector machine and convolutional neural network, which allow a high level of performance but with high computational cost in the training. In this paper, we propose the use of extreme learning neural networks to verify the writer identity based on simple graphemes with the aim of achieve a better descriptor performance in a less training time. The proposal allows verify peoples identity through the analysis of handwritten text in order to fakes detect, authorship identification, fakes, threats and thefts in documents. The experimental results show that this type of classifiers achieve a rate of success greater to the 95% for all five characters in the problem addressed, but with significantly less training times than traditionally used techniques.
Periodic orbits in dynamic systems with Wien Bridge
Authors: González J R , Ardila J G , Correa G 
Published: November 2020

AbstractThe following document showed the state space system that governs the behavior of the Wien Bridge, which is an electronic oscillator that generates sinusoidal waves, through an amplifier fed back by a bridge composed of four resistors and two capacitors. Through the simulations carried out, the existence of periodic orbits was verified when this system operates in a stable state. For this, the limit cycles were studied by being able to determine the origin of the periodic oscillation in the circuit in areas very close to the point of stability by means of the focus-center-limit cycle bifurcation presented in the Poincaré-Bendixon Theorem.
Effect of heavy metals (Ni, Cu, Pb) doped ZnO on the nonlinear optical properties
Authors: Salah Abeer , Aboud Ahmed A , Saad A M 
Published: November 2020

Abstract
In this paper, the non-linear optical properties of undoped and doped ZnO thin films were investigated. The films were doped with Ni, Pb, and Cu. an increase in the refractive index against wavelength is apparent for all films up to a certain value of wavelength. Z scan technique is used for measuring the nonlinear optical parameters via open and closed aperture configurations. Third order nonlinear susceptibilities (χ
(3)) of samples were calculated. The sign of nonlinear refractive index (n2) of ZnO was changed from positive (self-focus) to negative (de-focus) upon metal doping. Doping ZnO with heavy metals changes the sign of nonlinearity although the nonlinear absorption coefficient (β) is positive for all samples; the doped materials behave as optical limiters at high intensity. These materials are promising for optoelectronic devices and optical limiting applications.
S-band electron spin resonance spectroscopy using a short-circuited coplanar waveguide resonator
Authors: Roy Subhadip , Nandi Anuvab , Das Pronoy , Mitra Chiranjib 
Published: November 2020

Abstract
In this work, we study the development of a coplanar waveguide (CPW) resonator and its use in an electron spin resonance (ESR) spectrometer. The CPW resonator is designed to operate in S-band (2-4 GHz), with a short circuit configuration leading to miniaturization. It is so constructed such that it has a characteristic impedance of 50 ohms. The resonator supports quasi-TEM mode of propagation owing to its uniplanar nature, demanding detailed electromagnetic simulation. The design parameters and the electromagnetic field distribution are obtained from the simulation. The resonator is fabricated using optical lithography with a rapid prototyping technique. The characteristic response of the resonator is measured by coupling it to a Vector Network Analyzer (VNA). The ESR absorption spectrum of free radical 2,2-diphenyl-1-picrylhydrazyl (DPPH) is captured by using this resonator in reflection geometry. The microwave magnetic field distribution at the sample position is investigated. The ascertained value of Lande g-factor is consistent with that reported in the literature. Spin sensitivity of the order of 1015 spins/gauss is achieved upon using this resonator at room temperature. The quality factor of this resonator is found to be low and this makes it suitable for use in a Pulsed ESR spectrometer.
Gestational and Postpartum Weight Trajectories Among Women With and Without Asthma
Authors: Stevens Danielle R , Grobman William , Kumar Rajesh , Lipsky Leah M , Hinkle Stefanie N , Chen Zhen , Williams Andrew , Rohn Matthew C H , Kanner Jenna , Sherman Seth , Mendola Pauline 
Published: November 2020

AbstractAsthma leads to increased weight gain in nonpregnant populations, but studies have not examined this association within the context of pregnancy. The association between asthma and perinatal weight trajectories was examined in the Breathe—Wellbeing, Environment, Lifestyle, and Lung Function Study (2015–2019). Multilevel linear spline models were adjusted for age, race/ethnicity, income, marital status, education, cigarette smoking, parity, study site, and prepregnancy body mass index were used to examine differences in perinatal weight trajectories between women with (n = 299) and without (n = 101) asthma. Secondary analyses were conducted to assess whether associations differed by asthma phenotypes. At 40 weeks’ gestation, women with asthma gained 16.2 kg (95% confidence interval (CI): 14.6, 17.7) and women without asthma gained 13.1 kg (95% CI: 10.9, 15.4). At 3 months postpartum, women with asthma retained 10.4 kg (95% CI: 8.9, 11.9) and women without asthma retained 8.0 kg (95% CI: 5.9, 10.2). Among women with asthma, exercise-induced asthma and step 3 asthma medications were associated with excess gestational weight gain. These study findings suggest women with asthma gain and retain more weight during pregnancy and postpartum than do women without asthma.
Sex and Age Differences in Ambulatory Blood Pressure Monitoring Tolerability
Authors: Khaddage Sarah J , Patterson Julie A , Sargent Lana J , Price Elvin T , Dixon Dave L 
Published: November 2020

Abstract

BACKGROUND
Clinical practice guidelines endorse using ambulatory blood pressure monitoring (ABPM) for the diagnosis and management of hypertension. However, ABPM is not always tolerated by patients, and differences between individuals according to age and sex remain unexplored.

METHODS
This is a post hoc analysis of a prospective, single-arm clinical trial (NCT03920956) that evaluated the feasibility of an ABPM service provided at 2 community pharmacies. Tolerability was assessed using a previously published survey, which included 7 yes/no questions and 8 answered on a scale of 0–10. Descriptive statistics and Chi-square analyses were used to summarize the data for the patient surveys and to describe sex and age differences in device tolerability.

RESULTS
Of the 52 subjects enrolled, 50 (96%) completed the survey; half were female with a mean (SD) age of 57.5 years (15.8). Chi-square analyses showed that compared with their male counterparts, females were more likely to find the monitor cumbersome to wear (76.2% vs. 40%, P = 0.014). Subjects under 55 years of age were more likely to be disturbed by the noise of the monitor during driving (38.1% vs. 4.2%, P = 0.005) and at other times (35.0% vs. 8.3%, P = 0.029), and to find the monitor embarrassing to wear (33.3% vs. 7.1%, P = 0.019).

CONCLUSIONS
Although ABPM was generally well-tolerated overall, we did identify age and sex differences in tolerability. These factors should be considered to ensure patient acceptance and tolerability of ABPM.
Designing a microbiological monitoring program for compounding facilities
Authors: Tharp Jamie C , Kullar Rajkiran K , Tupps Matthew A 
Published: November 2020

Abstract

Purpose
We describe the evolution of a large multicenter health system’s microbiological monitoring program to improve standardization of viable sample collection practices; results review, interpretation, and response; and record keeping. We also describe lessons learned and considerations for other organizations considering microbiological monitoring program enhancements.

Summary
Developing a robust microbiological monitoring program requires policy and procedure development; training and education of staff involved in viable sample collection, results interpretation, and investigations; establishing a robust sampling plan; reviewing trend data; reviewing systems data; and conducting investigations. Well-defined policies and procedures ensure consistent response to “out of level” (ie, violative) sampling results. Staff education ensures staff involved in microbiological monitoring are educated on adequate sampling techniques and microbial contamination sources and mitigation strategies. Thorough record keeping is essential for microbiological monitoring sampling activities and ongoing systems monitoring. The records should include results, investigations, assessments, recommendations, and records of completed follow-up actions.

Conclusion
Facilities management requires a comprehensive microbiological monitoring and systems monitoring plan. In health systems with multiple sites, a centralized oversight and management program may be beneficial to standardize records, response planning, and overall control of controlled compounding environments.
Is Urinary Chromium Specific to Hexavalent Chromium Exposure in the Presence of Co-exposure to Other Chromium Compounds? A Biomonitoring Study in the Electroplating Industry
Authors: Martin Remy Aurélie , Robert Alain , Jacoby Nadège , Wild Pascal 
Published: November 2020

Abstract

Objectives
Electroplating processes are widely used in metal industries to improve the resistance properties of manufactured metal parts. Workers in this industry are potentially exposed both to hexavalent chromium (Cr(VI)) and to other chromium compounds [mostly trivalent chromium (Cr(III))], due to the use of chromic acid baths. The goal of this study was to validate urinary chromium as a Cr(VI) exposure biomarker in the presence of exposure to other chromium compounds.

Methods
A biomonitoring study consisted in monitoring airborne chromium exposure and urinary chromium for one working week in 93 workers from nine electroplating companies. Chromium concentrations were measured in all urinations of each volunteer for the working week. Individual airborne soluble and insoluble Cr(VI) as well as Cr(III) concentrations were measured for all of the shifts of the week. The main statistical analysis consisted in modelling, in a Bayesian framework, the pre- and post-shift urinary chromium as a function of airborne Cr(III) and airborne Cr(VI), taking into account the day of the week and the time of collection of the urines (pre- or post-shift).

Results
Preliminary descriptions showed an increase in pre-shift urinary chromium during the working week. The model showed an increase in urinary chromium over the shift related to the shift-specific airborne Cr(VI) concentration as well as an increasing trend over the week and a relationship with the mean weekly Cr(VI) thought to reflect chronic exposure. Taking into account the Cr(VI) exposure, there was no evidence of an effect of Cr(III) exposure on urinary chromium. A biological limit value (BLV) was derived from the French occupational exposure limit for Cr(VI) of 1 µg m−3 and was estimated at between 1.9 and 2.6 µg g−1 creatinine for a urinary sample collected at the end of the shift on the last working day of the week.

Conclusions
In the present context of mixed exposure to Cr(III) and Cr(VI) in electroplating, this study showed that urinary chromium depended only on airborne Cr(VI) concentrations, which justifies using a BLV for assessing workers’ exposure. The estimated BLV was close to the recommended French BLV, which is 1.8 µg g−1 creatinine, in the electroplating industry.