bluuebunny/crossref_metadata_2025 huggingface dataset:
Bicrystalline zinc oxide nanocombs
Authors: Huang Yun-Hua  , Zhang Yue  , Bai Xue-Dong  , He Jian  , Liu Juan  , Zhang Xiao-Mei  ,   (1)北京科技大学材料物理与化学系，北京  100083; (2)北京科技大学材料物理与化学系，北京  100083;北京科技大学固体电解质冶金测试技术国家专业实验室，北京  100083; (3)中国科学院物理所表面物理国家重点实验室，北京  100080
Published: December 2020

Bicrystalline ZnO nanocombs have been prepared by zinc powder evaporation proces s at 650℃. The structure of bicrystalline ZnO nanocombs was characterized by XR D, HTEM, SAD, etc., which indicate that the as-synthesized sample are composed of two crystals that form a twin structure parallel to the (1 1 3) plane with th e growth direction of the branching nanowires and the main stems closely paralle l to〈0 0 0 1〉 and〈0 1 1 0〉，respectively. Due to the unique twin structures, both sides of the main stems could be Zn-terminated ZnO (0 0 0 1) polar surface s, which are chemically active. Therefore the aligned branching nanowires can be grown from both sides of the main stems, which is consistent with the structure of the bicrystalline nanomaterials we have obtained. The growth of bicrystallin e ZnO nanocombs bears direct evidence to the polar-surface dominated growth mech anism of the ZnO nanomaterials.
Etching effects of low energy argon ion beam on porous anodic aluminum oxide membranes
Authors: Wang Sen  , Yu Guo-Jun  , Gong Jin-Long  , Li Qin-Tao  , Zhu De-Zhang  , Zhu Zhi-Yuan  ,   中国科学院上海应用物理研究所，上海  201800
Published: December 2020

Porous anodic aluminum oxide (AAO) membranes were sputtered by 500eV argon ion ( Ar+) beam. Scanning electron microscopy and atomic force microscopy i mages show that not only the barrier layer of AAO can be easily removed by Ar+ beam sputtering, but also several categories of surface morphologies w ere got by changing the incidence parameters. For instance, off-normal incidence bombardment results in ripple formation on the surface of AAO and off-normal in cidence during smple stage rotation leads to AAO surface smoothing. Theory of ri pple formation and evolution on amorphous substrate under ion beam irradiation d eveloped by Bradley and Harper is used to interpret the characteristics of rippl es on AAO surface.
New foldons and their elastic interactions in the (2+1)-dimensional modified Veselov-Novikov system
Authors: Shen Shou-Feng  , Zhang Jun  ,   浙江工业大学数学系，杭州  310014
Published: December 2020

By using Mathematica and multi-linear variable separation(MLVS) approach which is based on the Bcklund transformations, a new exact solution which include low dimensional arbitrary functions of the (2+1)-dimensional modified Veselov-Novikov system is obtained. Two new foldons are constructed and their entirely elastic interactions are considered. In additon, foldon and ghoston interactions are derived. MLVS approach is also extended to solve a new (1+1)-dimensional nonlinear system.
Entanglement entropy of the Gibbons-Maeda dilaton black hole
Authors: Liu Cheng-Zhou  , Zhao Zheng  ,   (1)北京师范大学物理系,北京  100875; (2)北京师范大学物理系,北京  100875;滨州学院物理与电子科学系,滨州  256600
Published: December 2020

By using the entanglement entropy method, in the Gibbons-Maeda(G-M) dilaton space-time, the statistical entropy of the quantum field in a thin film is calculated and the Bekenstein-Hawking entropy of the G-M dilaton black hole is obtained.Here, the quantum field is entangled with the quantum states in the black hole and the thin film sticks to the event horizon from outskirt of the black hole.Taking into account the effect of the generalized uncertainty principle on the quantum state density, the difficulty of the divergence of the state density near the event horizon in the brick-wall model is removed.Calculating the statistical entropy of the degrees of freedom entangling to the quantum states in the black hole in the quantum field outside the brick-wall and comparing the result to the entropy from the degrees of freedom inside brick-wall, we see that the two results are consistent but the latter may embody preferably the essence of black hole entropy.Using the residue theorem, the integration difficulty in he calculation is overcome and the result of the paper is founded quantitatively. These calculation and discussion imply that the high density quantum states near the event horizon are strongly correlated with the quantum states in black hole and the ultraviolet cut-off in the brick-wall model is not reasonable. The quantization of gravity field should be considered in the high energy quantum field near the event horizon and the ultraviolet cut-off is not necessary. In the quantum field inside and outside the brick-wall, the degrees of freedom contributing to the black hole entropy are just those correlating with the degrees of freedom in the black hole.
Orthogonality relations among modes in left-handed materials slab waveguide
Authors: Zhang Gao-Ming  , Peng Jing-Cui  , Jian Zhi-Jian  , Huang Xiao-Yi  ,   湖南大学应用物理系，长沙  410082
Published: December 2020

Based on the electromagnetic theory and by adopting the method of direct calculation, this paper proves that the modes of left-handed materials slab waveguide are orthogonal among each other, i.e. the fast waves, the slow waves, and the radiation modes are orthogonal among each other. This work provides a basis to study modes conversion in left-handed materials slab waveguide.
Experimental studies of the argon-puff Z-pinch implosion process
Authors: Huang Xian-Bin  , Yang Li-Bing  , Gu Yuan-Chao  , Deng Jian-Jun  , Zhou Rong-Guo  , Zou Jie  , Zhou Shao-Tong  , Zhang Si-Qun  , Chen Guang-Hua  , Chang Li-Hua  , Li Feng-Ping  , Ouyang Kai  , Li Jun  , Yang Liang  , Wang Xiong  ,   中国工程物理研究院流体物理研究所，绵阳  621900
Published: December 2020

A preliminary experiment for studying the argon-puff Z-pinch implosion process has been performed on the Yang accelerator. The ten-frame nanosecond temporal and spatial gated camera，visible high-speed scanning camera, differential laser interferometer, X-ray time integration pinhole camera and X-ray power system have been used to investigate the evolution of the argon-puff Z-pinch. Some typical results of argon-puff Z-pinch during implosion and pinch phase, including the “zipper” effect, necking phenomenon, sausage instability，temperature changes and the effect of load current rise time, are given and analyzed as examples, and some relevant conclusions are drawn.
Electronic theoretical study of stress corrosion mechanism of Ti metal
Authors: Liu Gui-Li  ,   沈阳工业大学工程力学研究所，沈阳  110023
Published: December 2020

In order to reveal the nature of the stress corrosion of Ti theoretically, the a tomic cluster model of α-Ti and the crack formed by dislocation accumulation wa s set up. The electronic structure parameters (Fermi energy level, structure ene rgy, surface energy, cluster energy and environment-sensitive embedding energy) of α-Ti and the crack were calculated by using the recursion method. The calcul ated results show that the environment-sensitive embedding energy of H atoms in the region of crack is smaller than that in the perfect area of α-Ti, so H atom s are apt to segregate at the crack. The positive cluster energy of H atoms in t he region of the crack in Ti metal shows that H atoms can not form cluster and h ave the tendency of forming ordered phases (hydrides). When H atoms accumulate o n the surface of the crack, they reduce the surface energy of the crack, making the crack propagation easier. The Fermi energy of the tip of crack is higher th an that in other areas, so electrons move to the perfect region of α-Ti from th e tip of crack, leading to the formation of the potential difference between the crack tip and the perfect region of α-Ti, then the dissolution-corrosion proce ss of crack tip as anode occurs under the action of the electrolyte.
Tunable ultra-short optical pulse source based on reflective semiconductor fiber ring laser
Authors: Xu Fan  , Zhang Xin-Liang  , Liu De-Ming  , Huang De-Xiu  ,   华中科技大学光电子工程系和武汉光电国家实验室，武汉  430074
Published: December 2020

Ultra-short optical pulse source is one of key components in optical time-division multiplexing(OTDM) system. In this paper, a wavelength and repetition rato tunable actively mode-locked fiber ring laser based on cross-gain modulation in a reflective Semiconductor Optical Amplifier(SOA) is demonstrated. Theoretical model for this scheme is also established and output characteristics are calculated. Stable picosecond pulse trains with high extinction ratio at 10—40 GHz repetition rato are obtained. 30nm wavelength tuning range is also achieved in our proposed actively mode-locked laser.
Sea-air oscillator model for equatorial eastern Pacific SST
Authors: Mo Jia-Qi  , Wang Hui  , Lin Wan-Tao  , Lin Yi-Hua  ,   (1)LASG,中国科学院大气物理研究所，北京  100029; (2)安徽师范大学，芜湖  241000;上海高校计算科学E-研究院，上海交通大学研究所，上海  200240;湖州师范学院，湖州  313000; (3)中国气象科学研究院，北京  100081
Published: December 2020

A sea-air oscillator model of the nonlinear coupling system is studied.Using the variational iteration principle,a series of corresponding functional is constructed.Then the Lagrange operators are selected.Finally,using the generalized variational iteration method,the approximate sequences of a series of solutions for the sea-air oscillator model are obtained.
Multiple velocity difference model and its stability analysis
Authors: Wang Tao  , Gao Zi-You  , Zhao Xiao-Mei  ,   北京交通大学交通运输学院系统科学所，北京  100044
Published: December 2020

Based on the full velocity difference (FVD) model proposed by Jiang and Wu, we present an extended car_following model, called the multiple velocity difference (MVD) model. We attempt to enhance the stability of the traffic flow by using the velocity differences of multiple vehicles. It can be found that the critical value of the sensitivity in the MVD model decreases and the stable region is apparently enlarged, compared with the FVD model. Additionally, the simulated results suggest that the MVD model can suppress the traffic jam effectively.
Fabrication of photonic crystals with different surface orientation by holographic lithography
Authors: Zhong Yong-Chun  , Zhu Shao-An  , Wang He-Zhou  , Zeng Zhao-Hua  , Chen Yong-Lie  ,   (1)中山大学超快速激光光谱学国家重点实验室，广州  510275; (2)中山大学高分子研究所，广州  510275
Published: December 2020

A diamond_like structure, which has a large complete photonic band gap and needs only a low refractive index contrast to open the complete photonic band gap, have been fabricated using four umbrellalike beams. By use of special prism to match the beams, diamond_like crystals with special surface orientations have been fabricated. The capability and feasibility of this method have been demonstrated by the fabrication of long_range ordered diamond_like microstructures with (114) and (110) surface orientation. The fabrication of large crystals with adjustable surface orientations will be advantageous to the systematic investigation of photonic properties such as negative reflection etc.
Ab initio study on the second-order nonlinear optical properties of some coumarin derivatives
Authors: Liang Xiao-Rui  , Zhao Bo  , Zhou Zhi-Hua  ,   南京师范大学化学与环境科学学院，南京  210097
Published: December 2020

The molecular structure of a series of coumarin derivatives were optimized and their second_order nonlinear optical polarizabilities(β) were calculated by the restricted Hartree_Fock (RHF) ab initio level with the 6_31G basis set in Gamess package. The results include both the distribution of charges in the ground and the excitated state and β under the external field(λ=1064nm). It is revealed that this kind of compounds have fairly large second_order polarizabilities. Moreover, there is close relation between the best structures and the high values of β. So we consider that this series of compounds are worthy of being studied further.
Optical conductivity of decagonal quasicrystals
Authors: Qiu Sheng-De  , Hu Cheng-Zheng  , Wang Ai-Jun  , Zhou Xiang  ,   武汉大学物理科学与技术学院，武汉  430072
Published: December 2020

A disscussion is given of the optical conductivity of decagonal quasicrystals. With group theory it is proved that decagonal quasicrystals may have different optical conductivity in the periodic and quasiperiodic directions. The formula is derived for the optical conductivity. The optical conductivity of Al65Co17Cu18 is calculated using this formula.　The calculated results basically agree with the experimental data.
Simulation of multiple grains for isothermal solidification of binary alloy using phase-field model
Authors: Lu Yang  , Wang Fan  , Zhu Chang-Sheng  , Wang Zhi-Ping  ,   兰州理工大学 甘肃省有色金属新材料省部共建国家重点实验室，兰州  730050
Published: December 2020

The phase-field model based on Kim model which couples the solute field is used to simulate microstructural dendrite growth of multiple grains for Al-2-mole-Cu alloy. In order to improve the efficiency of calculation, an interpolative method is used to achieve the coupling of the macro field with the micro field. The influence of different undercooling on shapes of dendrites and distribution of solute is studied.The result shows that the re-distribution of solute can decrease the melting point of the alloy, and reduce the practical undercooling, so the constitutional supercooling can influence the growth rate and solute distribution of dendrites by decreasing the freezing point evidently, and at the same time results in the cease of growth for both collided dendrites and perferred growth in directions of unhindered grains.
Linear Stark effect of CdS/HgS/CdS spherical nanometric system
Authors: Zheng Rui-Lun  , Wen Guo-Zhi  ,   西南大学物理学院，重庆 400715
Published: December 2020

Electronic energy and wave function of three-layer spherical nanometric system in homogeneous electric field is solved, the influence of applied field and sample size to the shift of Stark energy level is discussed.
Chemical surface treatment and charge stability of polypropylene cellular electret film
Authors: An Zhen-Lian  , Tang Min-Min  , Xia Zhong-Fu  , Sheng Xiao-Chen  , Zhang Xiao-Qing  ,   同济大学波耳固体物理研究所，上海  200092
Published: December 2020

The charge stability has been systematically studied by measuring open-circuit thermally stimulated discharge (TSD) current spectra, in situ TSD charge spectra and isothermal charge decay for the polypropylene (PP) cellular films after chemical treatments ( extraction, oxidation and HF solution treatment). The results showed that a very strong new current peak, which the virginal film does not have, appeared at about 184℃ in the TSD current spectrum of the PP cellular film properly oxidized and then HF-treated at room temperature (RT), and that its charge storage thermal stability is significantly improved compared with that of the virginal PP film, and is enhanced further by high temperature charging method. The reason that charge stability of the HF-treated PP films is improved has been clarified by attenuated total reflection infrared (ATR-IR) spectroscopy. The charge stability of treated films can be improved by appropriately prolonging either HF treatment time at RT or oxidation time. The theory of in situ TSD charge indicates that an in situ TSD charge spectrum contains combined information on the changes of the mean charge depth of the deposited charge layer and the deposited charge value. Combining the TSD current spectrum and the initial mean charge depth of a PP cellular film at RT, the change of the mean charge depth can be in situ investigated in heating process.
Influence of doping Al at Fe site on the magnetic structure and magnetotransport properties of Sr2FeMoO6
Authors: Wang Xian-Jie  , Sui Yu  , Qian Zheng-Nan  , Liu Zhi-Guo  , Miao Ji-Peng  , Huang Xi-Qiang  , Lü Zhe  , Zhu Rui-Bin  , Cheng Jin-Guang  , Su Wen-Hui  ,   (1)哈尔滨工业大学应用物理系凝聚态科学与技术研究中心，哈尔滨  150001; (2)哈尔滨工业大学应用物理系凝聚态科学与技术研究中心，哈尔滨  150001；中国科学院国际材料物理中心，沈阳  110015
Published: December 2020

Double perovskite Sr2FeMoO6 with Al doping at Fe site up to 30% were prepared by traditional solid-state reaction. The degree of the cation ordering of Sr2FeMoO6 increases with Al doping obviously as shown by the refinement of room-temperature X-ray diffraction. The saturated magnetic moment per formula unit of these compounds decreases gradually with increasing Al concentration, but the magnetic moment per Fe ion increases markedly, which is consistent with the improvement of cation ordering. Basing on the analysis of magnetic structure with Al doping, doping of Al will lead to the formation of non-magnetic coupled Mo—O—Al—O—Mo chains, which can divide the large Mo—O—Fe ferrimagnetic region into smaller patches and enhance the low field magnetoresistance. The formation of Fe—O—Fe antiphase boundaries are suppressed by the doping Al due to the improvement of the cation ordering, and the high field magnetoresistance that roots in spin-dependent scattering at the antiphase boundaries is reduced. Therefore, the total magnetoresistance reaches a maximum value at x=0.15.
Growth of carbon nanotips by plasma-enhanced hot filament chemical vapor deposition
Authors: Wang Bi-Ben  , Xu Xing-Zi  , Zhang Bing  ,   (1)北京工业大学应用数理学院，北京  100022; (2)重庆大学材料科学与工程学院，重庆  400044
Published: December 2020

Carbon nanotips were prepared by plasma-enhanced hot filament chemical vapor deposition under different bias current using CH4, NH3 and H2 as the reaction gases, and investigated by scanning electron microscopy and micro-Raman spectrometer. The results indicate that the carbon nanotips have graphite structure. With increasing of the bias current, the tip angles of the carbon nanotips are reduced and their growth rate are increased. Combined with theory related to plasma and sputtering, the formation of the carbon nanotips and the change of their growth rate with the bias current are discussed.
Wavelet-based multifractal analysis of ground electric field before occurrence of strong discharge in thunderstorm
Authors: Gou Xue-Qiang  , Zhang Yi-Jun  , Dong Wan-Sheng  ,   (1)中国科学院寒区旱区环境与工程研究所，兰州  730000; (2)中国科学院寒区旱区环境与工程研究所，兰州  730000;西北师范大学物理与电子工程学院,兰州  730070
Published: December 2020

It is considered that complex systems far from equilibrium are evolved in avalanche and self similar multiplicative cascade way, and have characteristics of multifractality. By using the ground electric field data obtained in the middle of Qinghai-Xizang plateau region, multifractal behavior of lightning discharges in thunderstorm is investigated with wavelet-based multifractal method. It is found that strong singularity and multfractality are involved in the strong lightning discharges, the minimum exponent αmin is less than -0.3, and the width of spectrum Δα is greater than 1.6, and the scaling behavior is consistent with the modified version of the binomial multiplicative cascade multifractal model. It is also shown that Δα increases with the enhancing of the discharge activity, and strong lightning happens in regions where Δα is high or is decreasing, the related reason is discussed.
The neural networks method for detecting weak signals under chaotic background
Authors: Xing Hong-Yan  , Xu Wei  ,   南京信息工程大学电子与信息工程学院，南京 210044
Published: December 2020

A method for detecting weak signals embebed in chaotic noise by neural networks based on the theory of phase space reconstruction of the complicated nonlinear system is presented. One-step predictive model for chaotic background is built by neural network that possess powerful cap ability of learning and nonlinear processing. Then the weak transient signal or periodic signal which is embedded in the chaotic background can be detected from the predictive error. And the detecting ability of this method when the chaotic background is mixed with white noiseis studied. The difference in the detecting principle for the transient signal and periodic signal is pointed out. The experiment which takes the Lorenz system as chaotic background shows this method can effectively detect very weak signals embedded in the chaotic background.
Multiscale entropy and dynamic characteristics of two-phase flow patterns
Authors: Zheng Gui-Bo  , Jin Ning-De  ,   天津大学电气与自动化工程学院，天津  300072
Published: December 2020

Multiscale entropy is a new method to analyze nonlinear time series on multiple temporal and spatial scales. Firstly，multiscale entropy characteristics of several typical nonlinear series were studied，and then based on this，the fluctuant conductance signals of 144 two-phase flow conditions were analyzed，which were collected by using array conductance sensors in upward vertical gas-liquid two-phase flow. The results indicated that the changing rate of sample entropy at small scales could be used to classify the three typical flow patterns （bubble flow，slug flow and churn flow），and the fluctuation of sample entropy of large scales reflected the dynamic characteristics of each flow pattern. The stochastic characteristic of bubble flow was shown as higher and oscillating sample entropy at large scales; the intermittence of gas slug and liquid slug of slug flow was represented as lower and stable sample entropy of large scales; the unstable and oscillating characteristics of churn flow behaved as the entropy between that of bubble flow and slug flow，and the entropy closed to that of bubble at larger scales. The multiscale entropy analysis of two-phase flow is helpful for understanding the dynamic characteristics of flow pattern transition，and the rate of multiscale entropy is a new indicator of flow pattern identification.
Foot Loading Associated with Barefoot, Shod, and Minimalist Running in Male Rearfoot Strikers
Authors: Debugne Gauthier , Eerdekens Maarten , Peters Helen , Staes Filip , Bertucii William , Deschamps Kevin
Published: December 2020

Background

We aimed to determine the center of pressure (COP) trajectories and regional pressure differences in natural rearfoot strikers while running barefoot, running with a minimalist shoe, and running with a traditional shoe.

Methods

Twenty-two male natural rearfoot strikers ran at an imposed speed along an instrumented runway in three conditions: barefoot, with a traditional shoe, and with a minimalist shoe. Metrics associated to the COP and regional plantar force distribution, captured with a pressure platform, were compared using one-way repeated-measures analysis of variance.

Results

The forefoot contact phase was found to be significantly shorter in the barefoot running trials compared with the shod conditions (P = .003). The initial contact of the COP was located more anteriorly in the barefoot running trials. The mediolateral position of the COP at initial contact was found to be significantly different in the three conditions, whereas the final mediolateral position of the COP during the forefoot contact phase was found to be more lateral in the barefoot condition compared with both shod conditions (P = .0001). The metrics associated with the regional plantar force distribution supported the clinical reasoning with respect to the COP findings.

Conclusions

The minimalist shoe seems to provide a compromise between barefoot running and running with a traditional shoe.
Risk Factors Associated with 30-Day Readmission in Patients with Diabetic Foot Infections
Authors: Miller Marshall , Knepper Bryan , Young Heather
Published: December 2020

Background

Diabetic foot infections (DFIs) are the most common cause of hospitalization for patients with diabetes. Studies have shown diabetic patients have high readmission rates. It is important to identify variables that contribute to readmission. This study aimed to investigate clinical variables associated with 30-day hospital readmission in patients with DFI.

Methods

We conducted a retrospective study of adults admitted to the hospital for DFI between July 1, 2012, and July 1, 2015. We identified patients by International Classification of Diseases, Ninth Revision codes and randomly selected 35% of medical records for review. Patients were excluded if they did not have a DFI by review, were pregnant, or were incarcerated. The primary outcome was 30-day readmission. Data collected included baseline demographics, medical comorbidities, substance abuse, homelessness, tobacco use, and laboratory and surgical pathology data. Univariate and multivariate logistic regression models were used to identify independent predictors.

Results

Of 140 included patients, 106 (76%) were male. Median age was 55 years and length of stay (LOS) was 7 days. In univariate analysis, 31 patients (22%) were readmitted in the 30 days after the index hospitalization. Factors associated with readmission included treatment failure, elevated C-reactive protein level, and hospital LOS (P < .05). In multivariate analyses, LOS and treatment failure were independent predictors of readmission.

Conclusions

The 30-day readmission rate for patients with DFI is high. Treatment failure, C-reactive protein, and LOS are independently associated with readmission. More work is needed to determine reasons for readmission so that appropriate measures can be taken before discharge.
Characterization of sediment microbial communities at two sites with low hydrocarbon pollution in the southeast Gulf of Mexico
Authors: Suárez-Moo Pablo , Lamelas Araceli , Garcia-Bautista Itza , Barahona-Pérez Luis Felipe , Sandoval-Flores Gloria , Valdes-Lozano David , Toledano-Thompson Tanit , Polanco-Lugo Erik , Valdez-Ojeda Ruby
Published: December 2020

Background

Coastal ecosystems are prone to hydrocarbon pollution due to human activities, and this issue has a tremendous impact on the environment, socioeconomic consequences, and represents a hazard to humans. Bioremediation relies on the ability of bacteria to metabolize hydrocarbons with the aim of cleaning up polluted sites.

Methods

The potential of naturally occurring microbial communities as oil degraders was investigated in Sisal and Progreso, two port locations in the southeast Gulf of Mexico, both with a low level of hydrocarbon pollution. To do so, we determined the diversity and composition of bacterial communities in the marine sediment during the dry and rainy seasons using 16S rRNA sequencing. Functional profile analysis (PICRUTSt2) was used to predict metabolic functions associated with hydrocarbon degradation.

Results

We found a large bacterial taxonomic diversity, including some genera reported as hydrocarbon-degraders. Analyses of the alpha and beta diversity did not detect significant differences between sites or seasons, suggesting that location, season, and the contamination level detected here do not represent determining factors in the structure of the microbial communities. PICRUTSt2 predicted 10 metabolic functions associated with hydrocarbon degradation. Most bacterial genera with potential hydrocarbon bioremediation activity were generalists likely capable of degrading different hydrocarbon compounds. The bacterial composition and diversity reported here represent an initial attempt to characterize sites with low levels of contamination. This information is crucial for understanding the impact of eventual rises in hydrocarbon pollution.
Detection and estimating the blood accumulation volume of brain hemorrhage in a human anatomical skull using a RF single coil
Authors: Oziel Moshe , Rubinsky Boris , Korenstein Rafi
Published: December 2020

Objective

An experimental study for testing a simple robust algorithm on data derived from an electromagnetic radiation device that can detect small changes in the tissue/fluid ratio in a realistic head configuration.

Methods

Changes in the scattering parameters (S21) of an inductive coil resulting from injections of chicken blood in the 0–18 ml range into calf brain tissue in a human anatomical skull were measured over a 100–1,000 MHz frequency range.

Results

An algorithm that combines amplitude and phase results was found to detect changes in the tissue/fluid ratio with 90% accuracy. An algorithm that estimated the injected blood volume was found to have a 1–4 ml average error. This demonstrates the possibility of the inductive coil-based device to possess a practical ability to detect a change in the tissue/fluid ratio in the head.

Significance

This study is an important step towards the goal of building an inexpensive and safe device that can detect an early brain hemorrhagic stroke.
Genetic diversity and population structure of eddoe taro in China using genome-wide SNP markers
Authors: Wang Zhixin , Sun Yalin , Huang Xinfang , Li Feng , Liu Yuping , Zhu Honglian , Liu Zhengwei , Ke Weidong
Published: December 2020

Taro (Colocasia esculenta) is an important root and tuber crop cultivated worldwide. There are two main types of taro that vary in morphology of corm and cormel, ‘dasheen’ and ‘eddoe’. The eddoe type (Colocasia esculenta var. antiquorium) is predominantly distributed throughout China. Characterizing the genetic diversity present in the germplasm bank of taro is fundamental to better manage, conserve and utilize the genetic resources of this species. In this study, the genetic diversity of 234 taro accessions from 16 provinces of China was assessed using 132,869 single nucleotide polymorphism (SNP) markers identified by specific length amplified fragment-sequencing (SLAF-seq). Population structure and principal component analysis permitted the accessions to be categorized into eight groups. The genetic diversity and population differentiation of the eight groups were evaluated using the characterized SNPs. Analysis of molecular variance showed that the variation among eight inferred groups was higher than that within groups, while a relatively small variance was found among the two morphological types and 16 collection regions. Further, a core germplasm set comprising 41 taro accessions that maintained the genetic diversity of the entire collection was developed based on the genotype. This research is expected to be valuable for genetic characterization, germplasm conservation, and breeding of taro.
Density-dependent condition of juvenile penaeid shrimps in seagrass-dominated aquatic vegetation beds located at different distance from a tidal inlet
Authors: Blanco-Martínez Zeferino , Pérez-Castañeda Roberto , Sánchez-Martínez Jesús Genaro , Benavides-González Flaviano , Rábago-Castro Jaime Luis , Vázquez-Sauceda María de la Luz , Garrido-Olvera Lorena
Published: December 2020

Seagrasses are critical habitats for the recruitment and growth of juvenile penaeid shrimps within estuaries and coastal lagoons. The location of a seagrass bed within the lagoon can determine the value of a particular bed for shrimp populations. Consequently, differences in the abundance of shrimp can be found in seagrasses depending on their location. As shrimp density increases, density-dependent effects on biological parameters are more likely to occur. However, knowledge about density-dependent processes on shrimp populations in nursery habitats remains limited. The present investigation was undertaken to examine the effects of population density on shrimp condition in two selected seagrass beds, located at different distance from a tidal inlet, one 25 km away (distant) and the other 1 km away (nearby), in a subtropical coastal lagoon. The study was based on monthly samplings during one year in Laguna Madre (Mexico), performing a total of 36 shrimp trawls (100 m2 each one) within each seagrass bed (n = 3 trawls per bed per month for 12 months). Shrimp density was related to the proximity to the tidal inlet (higher density was consistently observed in the nearby seagrass bed), which in turn adversely affected the condition of both species studied (Penaeus aztecus and P. duorarum). In this regard, the present study provides the first evidence of density-dependent effects on shrimp condition inhabiting a nursery habitat. Both shrimp species exhibited a negative relationship between condition and shrimp density. However, this pattern differed depending on the proximity to the tidal inlet, suggesting that shrimp populations inhabiting the nearby seagrass bed are exposed to density-dependent effects on condition; whereas, such effects were not detected in the distant seagrass bed. Shrimp density within the distant seagrass bed was probably below carrying capacity, which is suggested by the better shrimp condition observed in that area of the lagoon. Intra and interspecific competition for food items is surmised to occur, predominantly within seagrass beds near the tidal inlet. However, this hypothesis needs to be tested in future studies.
ENTRE LIVROS E FLORES: O OLHAR EM RESSURREIÇÃO
Authors: Leite Rangel Vagner
Published: December 2020

Ressurreição (1872), primeiro romance de Machado de Assis, é o nosso objeto de estudo. Para tanto, abordaremos um dos traços recorrentes na narrativa: a figuração do olhar e a sua função no romance. O objetivo é mostrar como o campo semântico do olhar, recorrente na dita primeira fase machadiana, é utilizado pelo narrador como estratégia narrativa de significação de um estado interior das personagens, que elas podem negacear, assim como um meio através do qual elas podem averiguar, para além dos jogos sociais de dissimulação, um possível efeito de verdade ou mentira plasmada no rosto de outras personagens, conforme a caracterização do olhar que encontramos na narrativa. Nossa hipótese: mesmo sendo garantia de verdade, o olhar não é suficiente para garantir o final feliz dos personagens principiais, porque o drama de Félix, personagem principal, não está no âmbito social, regido pela aparência, mas, sim, no âmbito pessoal, regido pelos costumes locais, pela tradição colonial que subsidia a decisão ulterior da personagem, ainda que ela apresente, na primeira metade da narrativa, uma aparência moderna.
Financial Inclusion and Output: Empirical Evidence from Nigeria
Authors: Anyaogu Nneka B. Charles-
Published: December 2020

The study is on the effect of financial inclusion on output in Nigeria. It made use of time series data sourced from Central Bank of Nigeria statistical bulletin for the period of 1992 to 2018. The Co-integration, Causality, Unit Root and the Ordinary Least Square tests were used for the analyses. The Causality test result shows a unidirectional causality flowing from Microfinance Bank Deposit to the Output, whereas a unidirectional causality existed between Loan and Advances and Output, with causality flowing from Output to Loan and Advances. The unit root test result shows that all the variables are stationary at first differencing. Besides, Output recorded a significant positive relationship with Bank Deposit but an insignificant relationship with Loan and Advances. However, there exists a long-run equilibrium relationship among the variables. This means that what existed in the short-run persisted in the long-run in the case of Bank Demand Deposit and Output. It goes on to show that the effect of Loan and Advances on Output is best felt at the long-run when companies that acquired the loan must have produced goods and services in the economy. The study recommends that Central Bank Nigeria and Commercial Banks should encourage financial inclusion since it has proven to have a great influence on the output. Also, Banking Services when extended to the remote areas will not only reduce financial exclusion but will enhance the output in the economy.
Estudo do potencial antifúngico e do mecanismo de ação do timol contra cepas de Candida parapsilosis resistentes ao fluconazol e a anfotericina B
Authors: Sousa Janiere Pereira de , Medeiros Cássio Ilan Soares , Pereira Fillipe de Oliveira , Guerra Felipe Queiroga Sarmento , Oliveira Filho Abrahão Alves de , Lima Edeltrudes de Oliveira
Published: December 2020

Objetivo: Investigar a suscetibilidade antifúngica do timol contra cepas de Candida parapsilosis isoladas de sangue humano, bem como seu possível mecanismo de ação. Métodos: Foram utilizadas técnicas de microdiluição em placas de 96 poços para determinar a concentração inibitória mínima (CIM) e concentração fungicida mínima (CFM). Além disso, foram realizados testes com o sorbitol e o ergosterol para investigar a ação do timol na parede e na membrana celular fúngica respectivamente. Resultados: Nos testes de CIM e CFM, foi observado que as cepas de C. parapsilosis são resistentes ao fluconazol e a anfotericina B, no entanto, o timol desempenhou efeito fungicida com razão CFM/CIM entre 1 e 2. Além disso, a CIM do timol não aumentou quando o sorbitol ou o ergosterol foi adicionado no meio, sugerindo fortemente que este monoterpeno não age na parede celular fúngica ou por ligação ao ergosterol na membrana plasmática. Conclusão: Portanto, esses resultados contribuem para a elucidação do mecanismo de ação do timol, sugerindo outros possíveis alvos de interação fármaco-receptor. No entanto, mais investigações de caráter enzimático e molecular em modelos in vitro são necessários para que se possa elucidar completamente o modo de ação desse promissor monoterpeno.
Resistome in gram-negative bacteria from soft cheese in Brazil
Authors: Silva Cristiane Rodrigues , Okuno Newton Takeshi , Macedo Victor Hugo Lima de Medeiros , Freire Isabela Da Rocha , Miller Rafael Monção , Marin Victor Augustus
Published: December 2020

ABSTRACT

 

Objectives: evaluation of antibiotic resistance in Gram-negative microbiota from ready-to-eat cheese samples.

Methodology: this research applied a specific method to evaluate the phenotypic susceptibility to antibiotics in a viable Gram-negative microbiota. The selected food was a cheese that is commonly consumed without thermal processing, the Minas Frescal cheese. The evaluation was followed by a PCR screening in this resistant microbiota, for genes that provide resistance to antibiotics and also to the quaternary ammonium.

Results: all cheese samples demonstrated a resistant microbiota. In 13.3% of the cheese samples analyzed, the resistance reached all ten different antibiotics tested and, in 80%, 8 to 10 different antibiotics. In antibiotics considered critics as the carbapenems: ertapenem presented resistant microbiota in 86.7% of the samples. In cephalosporins, the resistance reached 100% in the third generation (ceftazidime) and almost half of the samples (46.7%) in the fourth generation (cefepime). In genotypic research, seven different resistance genes were found in 69.2% of the bacterial pools, including the beta-lactamase-producing genes ctx, tem, shv, tetracycline resistant genes and a high rate of integrons class 1 and 2.
Conclusions: the results indicate phenotypically and genotypically that the Minas frescal cheese can present potential resistant microbiota. Therefore, the methodology used is a viable possibility and with a broader answer about the food microbiota role in resistance. This research corroborates the food area as an important sector to be managed to reduce the process of antibiotic resistance.
“HINGE HOUSE”: Space embracing plural people, activities, and objects by devising a timber frame joint
Authors: Tachibana Mio , Tsuboi Hirotsugu
Published: December 2020

We designed a house that embraces plural people, activities, and objects and where people act autonomously in a suburb of Tokyo. A new hinge joint and innovative timber framework were devised to implement the liberated ample space, and environmental strategies were adopted.
Filmless quality assurance of a Leksell Gamma Knife® Icon™
Authors: Maraghechi Borna , Kim Taeho , Mitchell Timothy J. , Goddu S. Murty , Dise Joe , Kavanaugh James A. , Zoberi Jacqueline E. , Mutic Sasa , Knutson Nels C.
Published: December 2020

Purpose

The annual quality assurance (QA) of Leksell Gamma Knife® (LGK) systems are typically performed using films. Film is a good candidate for small field dosimetry due to its high spatial resolution and availability. However, there are multiple challenges with using film; film does not provide real‐time measurement and requires batch‐specific calibration. Our findings show that active detector‐based QA can simplify the procedure and save time without loss of accuracy.

Methods

Annual QA tests for a LGK Icon™ system were performed using both film‐based and filmless techniques. Output calibration, relative output factors (ROF), radiation profiles, sector uniformity/source counting, and verification of the unit center point (UCP) and radiation focal point (RFP) coincidence tests were performed. Radiochromic films, two ionization chambers, and a synthetic diamond detector were used for the measurements. Results were compared and verified with the treatment planning system (TPS).

Results

The measured dose rate of the LGK Icon was within 0.4% of the TPS value set at the time of commissioning using an ionization chamber. ROF for the 8 and 4‐mm collimators were found to be 0.3% and 1.8% different from TPS values using the MicroDiamond detector and 2.6% and 1.9% different for film, respectively. Excellent agreement was found between TPS and measured dose profiles using the MicroDiamond detector which was within 1%/1 mm vs 2%/1 mm for film. Sector uniformity was found to be within 1% for all eight sectors measured using an ionization chamber. Verification of UCP and RFP coincidence using the MicroDiamond detector and pinprick film test was within 0.3 mm at isocenter for both.

Conclusion

The annual QA of a LGK Icon was successfully performed by employing filmless techniques. Comparable results were obtained using radiochromic films. Utilizing active detectors instead of films simplifies the QA process and saves time without loss of accuracy.
Driving Force and Optical Signatures of Bipolaron Formation in Chemically Doped Conjugated Polymers
Authors: Voss Matthew G. , Challa J. Reddy , Scholes D. Tyler , Yee Patrick Y. , Wu Eric C. , Liu Xiao , Park Sanghyun J. , León Ruiz Omar , Subramaniyan Selvam , Chen Mengdan , Jenekhe Samson A. , Wang Xiaolin , Tolbert Sarah H. , Schwartz Benjamin J.
Published: December 2020

Molecular dopants are often added to semiconducting polymers to improve electrical conductivity. However, the use of such dopants does not always produce mobile charge carriers. In this work, ultrafast spectroscopy is used to explore the nature of the carriers created following doping of conjugated push–pull polymers with both F4TCNQ (2,3,5,6‐tetrafluoro‐7,7,8,8‐tetracyanoquinodimethane) and FeCl3. It is shown that for one particular push–pull material, the charge carriers created by doping are entirely non‐conductive bipolarons and not single polarons, and that transient absorption spectroscopy following excitation in the infrared can readily distinguish the two types of charge carriers. Based on density functional theory calculations and experiments on multiple push–pull conjugated polymers, it is argued that the size of the donor push units determines the relative stabilities of polarons and bipolarons, with larger donor units stabilizing the bipolarons by providing more area for two charges to co‐reside.
Reaction Mechanism and Structural Evolution of Fluorographite Cathodes in Solid‐State K/Na/Li Batteries
Authors: Ding Zhengping , Yang Chen , Zou Jian , Chen Shulin , Qu Ke , Ma Xiumei , Zhang Jingmin , Lu Jing , Wei Weifeng , Gao Peng , Wang Liping
Published: December 2020

Fluorographites (CFx) are ultrahigh‐energy‐density cathode materials for alkaline‐metal primary batteries. However, they are generally not rechargeable. To elucidate the reaction mechanism of CFx cathodes, in situ transmission electron microscopy characterizations and ab initio calculations are employed. It is found that it is a two‐phase mechanism upon K/Na/Li ion insertion; crystalline KF (crystalline NaF nanoparticles and amorphous LiF) is generated uniformly within the amorphous carbon matrix, retaining an unchanged volume during the discharge process. The diffusivity for K/Na/Li ion migration within the CFx is ≈2.2–2.5 × 10–12, 3.4–5.3 × 10–12 , and 1.8–2.5 × 10–11 cm2 s–1, respectively, which is comparable to the diffusivity of K/Na/Li ions in liquid‐state cells. Encouraged by the in situ transmission electron microscopy (TEM) results, a new rechargeable all‐solid‐state Li/CFx battery is further designed that shows a part of the reversible specific discharge capacity at the 2nd cycle. These findings demonstrate that a solid‐state electrolyte provides a different reaction process compared with a conventional liquid electrolyte, and enables CFx to be partly rechargeable in solid‐state Li batteries.
Voluntary‐Opsonization‐Enabled Precision Nanomedicines for Inflammation Treatment
Authors: Li Shuya , Li Min , Huo Shaohu , Wang Qin , Chen Jing , Ding Shenggang , Zeng Zhutian , Zhou Wenchao , Wang Yucai , Wang Jun
Published: December 2020

Nanomedicines that target specific blood cells represent an emerging strategy to improve drug biodistribution. However, the protein corona usually disrupts nanomedicine targeting to cells and tissues. Herein, instead of exploring synthetic methods to mitigate the impact of the protein corona, its natural interactions with blood cells are leveraged and turn the protein corona into an active ingredient in treating lung inflammation. It is discovered that molecularly engineered liposomes with inverse phosphocholine lipids rapidly enrich complement fragment iC3b by “voluntary opsonization,” which triggers neutrophil hijacking through complement receptor 3 phagocytosis. This neutrophil targeting is cell‐state dependent as only those activated by acute inflammation display efficient neutrophil reconstruction. The liposome‐loaded neutrophils migrate across the alveolar‐capillary barrier, accumulate in the inflamed lung parenchyma within hours, and release their payloads to kill the bacteria. This work shows that, in addition to biological cells, the protein corona can be a new platform for active and precision nanomedicine.
Highly Uniform, Self‐Assembled AlGaN Nanowires for Self‐Powered Solar‐Blind Photodetector with Fast‐Response Speed and High Responsivity
Authors: Wang Danhao , Huang Chen , Liu Xin , Zhang Haochen , Yu Huabin , Fang Shi , Ooi Boon S. , Mi Zetian , He Jr‐Hau , Sun Haiding
Published: December 2020

Searching for power‐independent, compact, and highly environment‐sensitive photodetectors is a critical step towards the realization of next‐generation energy‐efficient and sustainable integrated optoelectronic systems. Particularly, the deep ultraviolet (UV) band, which has large photon energy, is extremely suitable for environment monitoring and invisible light communication application. Herein, the demonstration of self‐powered deep UV solar‐blind photodetectors in a photoelectrochemical (PEC) cell configuration is reported, adopting wide bandgap n‐type aluminum gallium nitride (AlGaN) nanowires as photoelectrode. After decorating nanowires with noble metal ruthenium (Ru), the constructed solar‐blind PEC photodetectors exhibited excellent responsivity of 48.8 mA W‐1, fast response speed (rise time of 83 ms and decay time of 19 ms) with large photocurrent density of 55 μA cm‐2 at 254 nm illumination. Such superior performance can be attributed to, firstly and foremost, the successful synthesis of highly uniform and defect‐free n‐type AlGaN nanowires which ensures efficient photogeneration via effective light‐harvesting, and secondly, the boosted carrier separation and collection efficiency through Ru decoration. This novel nanoarchitecture enables deep UV photodetection to work stably with low energy consumption, intriguingly, opening the possibility for the development of high‐performance PEC photodetectors based on group III‐nitride semiconductors covering the entire spectral range from infrared to deep UV.