bluuebunny/crossref_metadata_2025_split huggingface dataset:
The bifocal metalenses for independent focusing of orthogonally circularly polarized light
Authors: Chen Deli , Wang Junjie , Wang Shuai , Zhao Saili , Qi Yongle , Sun Xiaohong 
Published: December 2020

Abstract
Compared with traditional optical lenses, metalenses have obvious advantages of ultra-thin and easy-integration. In this paper, resonant phase and geometric phase are combined to design a metalens that can independently control the focus of right-handed circular polarization (RCP) and left-handed circular polarization (LCP) light. This solves the disadvantage that resonant phase or geometric phase alone cannot focus the RCP and LCP light at any two different positions simultaneously and independently. Two types of metalenses have been designed. One is off-axis metalens, which can focus RCP and LCP light in symmetric and asymmetric positions, respectively. The other is on-axis metalens, which can realize the bifocal effect of RCP and LCP light at different positions along the axis. Furthermore, by increasing the numerical aperture, the maximum electric field energy intensity and full width at half maximum of two focal points of the same metalens can gradually approach each other. This provides a new way for the regulation of polarization-dependent imaging, information detection, as well as the possibility of realizing multi-functional metasurface devices.
CdSe quantum dot organic solar cells with improved photovoltaic performance
Authors: Yang Xi-Kai , Qiao Jia-Wei , Chen Zhi-Hao , Wen Zhen-Chuan , Yin Hang , Hao Xiao-Tao 
Published: December 2020

AbstractWe adopt inorganic semiconducting CdSe quantum dots (QDs) as a third component in the PTB7-Th:PC71BM-based organic solar cells due to their advantages of strong absorbance, high conductivity, and good solution processability. With the blending of low-dosage CdSe QDs, the short-circuit current density (Jsc) and power conversion efficiencies can be improved by 13% and 11%, respectively, in the ternary device. Compared with the control device, CdSe QDs can effectively modulate the charge dynamics and lead to enhanced fluorescence external quantum efficiency. Moreover, effective Förster resonance energy transfer and fast charge transfer can be observed in the CdSe QD-based bulk-heterojunction (BHJ) films, and therefore improve the overall performance of the organic photovoltaic devices. This work provides an effective method by adopting CdSe QDs to fabricate high-performance PTB7-Th:PC71BM BHJ solar cells.
Mixed-phase effect of a high Seebeck coefficient and low electrical resistivity in Ag2S
Authors: Kim Gareoung , Byeon Dogyun , Singh Saurabh , Hirata Keisuke , Choi Seongho , Matsunami Masaharu , Takeuchi Tsunehiro 
Published: December 2020

Abstract
The improvement of thermoelectric performance is very challenging, because the thermoelectric properties, the Seebeck coefficient, electrical resistivity, and thermal conductivity are generally correlated with each other via a common physical quantity known as carrier concentration. In this study, we successfully achieved separate control of the thermoelectric properties of polycrystalline Ag2S using spatial-phase separation into low- and high-temperature phases using a configuration based on bottom heating and top measurement. We experimentally confirmed that the Seebeck coefficient was determined by the low-temperature phase at the top surface but the electrical resistivity was dominated by the high-temperature phase lying below the low-temperature phase. As a result, a high Seebeck coefficient (

∼
−
650
μ

V

K

−
1

) and low electrical resistivity (

∼
2

m
Ω

cm

) were simultaneously observed over a broad temperature range (390 ∼ 440 K). This experimental discovery suggests a new concept for thermoelectric materials and devices.
Liquid to supercooled-liquid crossover from a Boltzmann transport approach to escape and diffusion
Authors: Piscitelli A , Ciamarra M Pica 
Published: December 2020

Abstract
We develop a model describing the motion of a non-Brownian particle in a periodic potential, which we then use to predict the temperature dependence of the diffusivity of a glass-former. In the model, the velocity of the particle is drawn for the equilibrium distribution at rate 1/t
c, where t
c is the intercollision time in the relaxation time approximation. Solutions within a Boltzmann transport approach show that the diffusivity crossovers from a low-t
c regime in which the particle at most crosses a single barrier in between two successive collisions, to a high-t
c regime in which the particle may cross several barriers. We then use our model to predict the temperature dependence of the diffusion coefficient of a system of harmonic-spheres, whose energy landscape has features resembling those of the potential considered in our model. We successfully recover a crossover in the temperature dependence of the diffusion coefficient observed through numerical dynamics simulations, as well as the relationship of the diffusivity on the temperature in the high-temperature limit.
Using personal monitoring data to derive organ doses for medical radiation workers in the Million Person Study—considerations regarding NCRP Commentary no. 30
Authors: Yoder C , Balter S , Boice Jr J D , Grogan H , Mumma M , Rothenberg L N , Passmore C , Vetter R J , Dauer L T 
Published: December 2020

Abstract
The study of low dose and low-dose rate exposure is of central importance in understanding the possible range of health effects from prolonged exposures to radiation. The One Million Person Study of Radiation Workers and Veterans (MPS) of low-dose health effects was designed to evaluate radiation risks among healthy American workers and veterans. The MPS is evaluating low-dose and dose-rate effects, intakes of radioactive elements, cancer and non-cancer outcomes, as well as differences in risks between women and men. Medical radiation workers make up a large group of individuals occupationally exposed to low doses of radiation from external x-ray/gamma exposures. For the MPS, about 100 000 United States medical radiation workers have been selected for study. The approach to the complex dosimetry circumstances for such workers over three to four decades of occupation were initially and broadly described in National Council on Radiation Protection and Measurements (NCRP) Report No. 178. NCRP Commentary No. 30 provides more detail and describes an optimum approach for using personal monitoring data to estimate lung and other organ doses applicable to the cohort and provides specific precautions/considerations applicable to the dosimetry of medical radiation worker organ doses for use in epidemiologic studies. The use of protective aprons creates dosimetric complexity. It is recommended that dose values from dosimeters worn over a protective apron be reduced by a factor of 20 for estimating mean organ doses to tissues located in the torso and that 15% of the marrow should be assumed to remain unshielded for exposure scenarios when aprons are worn. Conversion coefficients relating personal dose equivalent, H
p(10) in mSv, to mean absorbed doses to organs and tissues, D
T in mGy, for females and males for six exposure scenarios have been determined and presented for use in the MPS. This Memorandum summarises several key points in NCRP Commentary No. 30.
The mechanical property and microscopic deformation mechanism of nanoparticle-contained graphene foam materials under uniaxial compression
Authors: Khan Muhammad Bilal , Wang Chao , Wang Shuai , Fang Daining , Chen Shaohua 
Published: December 2020

Abstract
Nanoparticle-contained graphene foams have found more and more practical applications in recent years, which desperately requires a deep understanding on basic mechanics of this hybrid material. In this paper, the microscopic deformation mechanism and mechanical properties of such a hybrid material under uniaxial compression, that are inevitably encountered in applications and further affect its functions, are systematically studied by the coarse-grained molecular dynamics simulation method. Two major factors of the size and volume fraction of nanoparticles are considered. It is found that the constitutive relation of nanoparticle filled graphene foam materials consists of three parts: the elastic deformation stage, deformation with inner re-organization and the final compaction stage, which is much similar to the experimental measurement of pristine graphene foam materials. Interestingly, both the initial and intermediate modulus of such a hybrid material is significantly affected by the size and volume fraction of nanoparticles, due to their influences on the microstructural evolution. The experimentally observed ‘spacer effect’ of such a hybrid material is well re-produced and further found to be particle-size sensitive. With the increase of nanoparticle size, the micro deformation mechanism will change from nanoparticles trapped in the graphene sheet, slipping on the graphene sheet, to aggregation outside the graphene sheet. Beyond a critical relative particle size 0.26, the graphene-sheet-dominated deformation mode changes to be a nanoparticle-dominated one. The final microstructure after compression of the hybrid system converges to two stable configurations of the ‘sandwiched’ and ‘randomly-stacked’ one. The results should be helpful not only to understand the micro mechanism of such a hybrid material in different applications, but also to the design of advanced composites and devices based on porous materials mixed with particles.
Phase-coherent transport in trigonal gallium nitride nanowires
Authors: Park Tae-Eon , Min Byoung-Chul , Lee Jaejun , Jeon Jeehoon , Lee Ki-Young , Choi Heon-Jin , Chang Joonyeon 
Published: December 2020

Abstract
Gallium nitride nanowires (GaN NWs) with triangular cross-section exhibit universal conductance fluctuations (UCF) originating from the quantum interference of electron wave functions in the NWs. The amplitude of UCF is inversely proportional to the applied bias current. The bias dependence of UCF, combined with temperature dependence of the resistance suggests that phase coherent transport dominates over normal transport in GaN NWs. A unique temperature dependence of phase-coherent length and fluctuation amplitude is associated with inelastic electron–electron scattering in NWs. The phase-coherence length extracted from the UCF is as large as 400 nm at 1.8 K, and gradually decreases as temperature increases up to 60 K.
Effectiveness of Hall current and ion slip on hydromagnetic biologically inspired flow of Cu − Fe
3
O
4/H
2
O hybrid nanomaterial
Authors: Akbar Y , Abbasi F M , Shehzad S A 
Published: December 2020

Abstract
Heat transfer augmentation is a significant concern in numerous engineering and industrial cooling/heating appliances nowadays. The usage of hybrid nanoliquids has been drawing attention of scientists in order to reduce the limitations of nanofluids and merge the chemical and physical characteristics of nanoparticles in an effective manner. Keeping such effectiveness in mind, present article aims to investigate the peristaltic flow of hybrid nanofluid with heat transfer and irreversibility analysis. Hybrid nanofluid is formed by mixing copper (Cu) and iron oxide (Fe
3
O
4) nanoparticles in water (H
2
O). The Cu − Fe
3
O
4 hybrid nanofluid with nanoparticles volume concentration 2% is used in this study. Impacts of Hall current, ion-slip, mixed convection and viscous dissipation are taken into consideration. Mathematical modeling for entropy generation is formulated via second law of thermodynamics. Governing equations of given problem are first converted into ordinary differential equations by employing lubrication approach. Obtained dimensionless equations are then tackled analytically with the aid of regular perturbation technique. Results reveal that temperature of hybrid nanofluid decreases by improving concentration of nanoparticles. Heat transfer rate at wall increases by improving Hartman number. Entropy generation reduces by improving Hall and ion-slip parameters. Bejan number increases by increasing Hartman number. Velocity of hybrid nanofluid increases by enhancing Grashof number. Pressure gradient of hybrid nanofluid increases by increasing Hall parameter. Pressure rise per wavelength decreases by enhancing ion-slip parameter. A comparison of temperature for base fluid, nanofluid and hybrid nanofluid is also furnished in tabular form. Additionally, comparison of numerical and analytical outcomes of velocity is also provided graphically. It is anticipated that the present study provides a theoretical data for the selection and design of hybrid nanofluid based heat exchanger.
Precise underwater distance measurement using laser frequency comb
Authors: Xu Xinyang , Zhao Haihan , Zhang Ziqiang , Zhai Jingsheng , Wu Hanzhong 
Published: December 2020

Abstract
Underwater distance measurement has been playing an important role in the fields of underwater navigation, search and rescue, and bathymetric survey. However, limited by the measurement sources (e.g. acoustic pulses or incoherent optical pulses), the precision can only achieve centimeter level at best, which greatly obstructs the advancement of underwater science and technology. Recent developments of optical frequency combs have given rise to revolutionary progress in metrology, spectroscopy, and optical distance measurement in air. However, frequency comb-based underwater distance measurement has rarely been reported. In this work, we describe a spectral interferometry-based method using a laser frequency comb at 518 nm (green light), which is capable of underwater distance measurement with high precision and accuracy. Due to the inherently dispersive characteristic of water, the measurement pulse will be chirped, and the spectrograms exhibit unstable oscillations, the spectral phase of which features a quadratic law. Distances up to 4.4 m and displacements down to 5 μm underwater can be determined by virtue of the spectral phases. The experimental results show the differences within ±4 μm at 4.4 m range, compared to the reference values. The Allan deviation is 1.596 μm at 5 s averaging time, 481 nm at 100 s averaging time, and can achieve 261 nm with 540 s averaging time. Our work could provide a promising and powerful tool for underwater distance measurement with high precision at long range, and open the door to a host of underwater applications related to the measurement of distance, e.g. mapping and positioning.
Effects of Accounting for Interval-Censored Antibody Titer Decay on Seroincidence in a Longitudinal Cohort Study of Leptospirosis
Authors: Owers Bonner Katharine A , Cruz Jaqueline S , Sacramento Gielson A , de Oliveira Daiana , Nery Nivison , Carvalho Mayara , Costa Federico , Childs James E , Ko Albert I , Diggle Peter J 
Published: December 2020

Abstract
Accurate measurements of seroincidence are critical for infections undercounted by reported cases, such as influenza, arboviral diseases, and leptospirosis. However, conventional methods of interpreting paired serological samples do not account for antibody titer decay, resulting in underestimated seroincidence rates. To improve interpretation of paired sera, we modeled exponential decay of interval-censored microscopic agglutination test titers using a historical data set of leptospirosis cases traced to a point source exposure in Italy in 1984. We then applied that decay rate to a longitudinal cohort study conducted in a high-transmission setting in Salvador, Brazil (2013–2015). We estimated a decay constant of 0.926 (95% confidence interval: 0.918, 0.934) titer dilutions per month. Accounting for decay in the cohort increased the mean infection rate to 1.21 times the conventionally defined rate over 6-month intervals (range, 1.10–1.36) and 1.82 times that rate over 12-month intervals (range, 1.65–2.07). Improved estimates of infection in longitudinal data have broad epidemiologic implications, including comparing studies with different sampling intervals, improving sample size estimation, and determining risk factors for infection and the role of acquired immunity. Our method of estimating and accounting for titer decay is generalizable to other infections defined using interval-censored serological assays.
Field Observations of Body Temperature for the Wolf Spider,Rabidosa rabida(Araneae: Lycosidae), Differ From Reported Laboratory Temperature Preference Suggesting Thermoconforming Behavior
Authors: Stork Ryan , Smith Payton , Aaen Corbin , Cooper Steve 
Published: December 2020

AbstractTemperature affects all aspects of ectotherm ecology, behavior, and physiology. Descriptions of thermal ecology are important for understanding ecology in changing thermal environments. Both laboratory and field estimates are important for understanding thermal ecology. Rabidosa rabida (Walckenaer 1837) (Araneae: Lycosidae) is a large wolf spider with some natural history, including laboratory estimates of thermal preference, tolerance, and performance, reported in the scientific literature. Laboratory tests suggest the active choice of temperature environment. To test published estimates of thermal ecology from the laboratory, we took body temperature measurements of mature spiders in the field nocturnally and diurnally using a FLIR camera in July 2019. We made comparisons between sexes and activity periods using field observations. We compared these measurements with the published values for thermal preferences and thermal maximum and with mean weather station data. Observed field temperatures differed significantly from published preference, but not from mean temperature from a local weather station. This suggests that this species is thermoconforming rather than actively thermoregulating. Reported thermal preference fell between the diurnal and nocturnal mean measurements closer to the diurnal than nocturnal temperatures. These field observations show how important it is to make field observations for physiology and thermal ecology. Maximum observed diurnal temperatures closely approached the published critical thermal maximum. We observed spiders performing behaviors such as hunting and feeding in conditions well above published thermal preference and near-critical high temperature. These observations suggest that R. rabida is thermoconforming in this limited period but does not rule out that they might thermoregulate in certain situations.
Neural circuit repair after central nervous system injury
Authors: Tsujioka Hiroshi , Yamashita Toshihide 
Published: December 2020

Abstract
Central nervous system injury often causes lifelong impairment of neural function, because the regenerative ability of axons is limited, making a sharp contrast to the successful regeneration that is seen in the peripheral nervous system. Nevertheless, partial functional recovery is observed, because axonal branches of damaged or undamaged neurons sprout and form novel relaying circuits. Using a lot of animal models such as the spinal cord injury model or the optic nerve injury model, previous studies have identified many factors that promote or inhibit axonal regeneration or sprouting. Molecules in the myelin such as myelin-associated glycoprotein, Nogo-A or oligodendrocyte-myelin glycoprotein, or molecules found in the glial scar such as chondroitin sulfate proteoglycans, activate Ras homolog A (RhoA) signaling, which leads to the collapse of the growth cone and inhibit axonal regeneration. By contrast, axonal regeneration programs can be activated by many molecules such as regeneration-associated transcription factors, cyclic AMP, neurotrophic factors, growth factors, mechanistic target of rapamycin or immune-related molecules. Axonal sprouting and axonal regeneration largely share these mechanisms. For functional recovery, appropriate pruning or suppressing of aberrant sprouting are also important. In contrast to adults, neonates show much higher sprouting ability. Specific cell types, various mouse strains and different species show higher regenerative ability. Studies focusing on these models also identified a lot of molecules that affect the regenerative ability. A deeper understanding of the mechanisms of neural circuit repair will lead to the development of better therapeutic approaches for central nervous system injury.
Murepavadin antimicrobial activity against and resistance development in cystic fibrosis Pseudomonas aeruginosa isolates
Authors: Díez-Aguilar María , Hernández-García Marta , Morosini María-Isabel , Fluit Ad , Tunney Michael M , Huertas Natalia , del Campo Rosa , Obrecht Daniel , Bernardini Francesca , Ekkelenkamp Miquel , Cantón Rafael 
Published: December 2020

Abstract

Background
Murepavadin, a novel peptidomimetic antibiotic, is being developed as an inhalation therapy for treatment of Pseudomonas aeruginosa respiratory infection in people with cystic fibrosis (CF). It blocks the activity of the LptD protein in P. aeruginosa causing outer membrane alterations.

Objectives
To determine the in vitro activity of murepavadin against CF P. aeruginosa isolates and to investigate potential mechanisms of resistance.

Methods
MIC values were determined by both broth microdilution and agar dilution and results compared. The effect of artificial sputum and lung surfactant on in vitro activity was also measured. Spontaneous mutation frequency was estimated. Bactericidal activity was investigated using time–kill assays. Resistant mutants were studied by WGS.

Results
The murepavadin MIC50 was 0.125 versus 4 mg/L and the MIC90 was 2 versus 32 mg/L by broth microdilution and agar dilution, respectively. Essential agreement was &gt;90% when determining in vitro activity with artificial sputum or lung surfactant. It was bactericidal at a concentration of 32 mg/L against 95.4% of the strains within 1–5 h. Murepavadin MICs were 2–9 two-fold dilutions higher for the mutant derivatives (0.5 to &gt;16 mg/L) than for the parental strains. Second-step mutants were obtained for the PAO mutS reference strain with an 8×MIC increase. WGS showed mutations in genes involved in LPS biosynthesis (lpxL1, lpxL2, bamA2, lptD, lpxT and msbA).

Conclusions
Murepavadin characteristics, such as its specific activity against P. aeruginosa, its unique mechanism of action and its strong antimicrobial activity, encourage the further clinical evaluation of this drug.