bluuebunny/crossref_metadata_2025 huggingface dataset:
Analysis and design of new chiral metamaterials with asymmetric transmission characteristics
Authors: Qiu Ke-Peng , Luo Yue , Zhang Wei-Hong ,   School of Mechanical Engineering, Northwestern Polytechnical University, Xi’an 710072, China
Published: December 2020

Asymmetric transmission (AT) metamaterials are extensively studied and applied in the fields of polarization converters and photodiodes. In order to further improve the properties of polarization conversion and unidirectional conduction in the high frequency band and to implement their tunability, the novel chiral electromagnetic metamaterials are studied. By the topology optimization technique, a new type of double-layer L-shaped variant metamaterial structure with excellent asymmetric transmission characteristics is designed. The objective function is to maximize the asymmetric transmission coefficient for the linear polarization wave. The rotationally symmetrical design domain is determined by considering polarization conversion and computation efficiency simultaneously. The design domain of upper layer is divided into two parts which are both the 180° rotationally symmetrical. The design domain of the upper layer and lower layer are the 90° rotationally symmetrical around the x and z axis respectively. Therefore, the number of design variables is only 18. Asymmetric transmission of linear polarization wave in the K band and Ka band are implemented. Numerical simulation results and experimental results show that the optimized chiral metamaterial has excellent asymmetric transmission characteristics, and its asymmetric transmission coefficient reaches 0.8562 at a frequency of 21.65 GHz and 0.8175 at a frequency of 28.575 GHz. Its asymmetric transmission mechanism is expounded by analyzing the electric field and surface current distribution at the resonance frequency. Based on the optimized chiral metamatertials, the reasonable geometric parameters are selected and the rotation angle of the metal layer is changed in order to further achieve the tunable AT characteristics. First, the influences of the dielectric substrate layer, the thickness of the metal layer and the side length of the grid on resonance frequency and asymmetric transmission coefficient are analyzed respectively, which provides the basis for the reasonable adjustment of the structural parameters to obtain better asymmetric transmission characteristics. After the reasonable geometric parameters are determined, the rotational angle of the upper metal layer and lower metal layer are changed. The linearly and circularly polarized wave are simultaneously achieved in the K band. In this article, the topology optimization technique is used to design the asymmetric transmission chiral metamaterial structure. The design process has a clear direction. The optimized asymmetric transmission chiral metamaterial has the simple structure type and the easy tunability of its asymmetric transmission characteristics. It can be used widely and easily in the fields of polarization converters and photodiodes. This design method has a broad application prospect in the chiral metamaterial field.
Research progress in rare earth doping photoluminescent ferroelectric thin films
Authors: Bao Ding-Hua ,   State Key Laboratory of Optoelectronic Materials and Technologies, School of Materials Science and Engineering, Sun Yat-Sen University, Guangzhou 510275, China
Published: December 2020

Rare earth doping is an important method to improve the properties of optoelectronic functional materials. Combining rare earth doping ferroelectric materials and rare earth photoluminescence can create new functional properties of ferroelectric materials. For example, choosing and using an appropriate rare earth element to be doped into a bismuth titanate ferroelectric material, the bismuth titanate will exhibit good photoluminescent properties as well as ferroelectric properties. Recently, photoluminescence properties originating from rare earth ions in oxide ferroelectric materials have attracted much attention for possible integrated photoluminescent ferroelectric device applications. In this paper, we briefly review the research status and progress of photoluminescence in rare earth photoluminescent ferroelectric materials, and we place the emphasis on our own research work in photoluminescent ferroelectric thin films such as (Bi,Eu)4Ti3O12, (Bi,Er)4Ti3O12, and codoped bismuth titanate thin films, and nanocomposite (Bi,Eu)4Ti3O12 ferroelectric thin films. Our results show that the rare earth doped bismuth titanate ferroelectric thin films exhibit good photoluminescent and ferroelectric properties due to unique compositions and layered perovskite structure, that the Eu3+ fluorescent structure probe can provide a new path for further studying the relationship between structure and property of Eu-doped ferroelectric thin films, that the rare earth photoluminescence can be used to examine the existence of morphotropic phase boundary in certain ferroelectric thin films such as Pr-doped x(K1/2Bi1/2)TiO3-(1－x)(Na1/2Bi1/2)TiO3 thin films, and nanocomposite materials of ZnO nanomaterials, and that Au nanoparticles, Ag nanoparticles with Eu-doped bismuth titanate exhibit obviously enhanced photoluminescent properties.
Theory of topological superconductivity based on Yu-Shiba-Rusinov states
Authors: Li Jian ,   School of Science, Westlake University, Hangzhou 310024, China,   Institute of Natural Sciences, Westlake Institute for Advanced Study, Hangzhou 310024, China
Published: December 2020

Yu-Shiba-Rusinov states are subgap bound states induced by magnetic impurity atoms in a superconductor. These states can be used as building blocks in constructing an effective topological superconductor. Here we formulate a unified theory of topological superconductivity in different dimensions based on Yu-Shiba-Rusinov states, and demonstrate its application with simple but illustrative examples. Such a theory underlies a number of recent experiments on the related platform.
Coherent or stochastic bi-resonance induced by conductance disturbance of chemical autapse
Authors: Qu Liang-Hui , Du Lin , Cao Zi-Lu , Hu Hai-Wei , Deng Zi-Chen ,   School of Mathematics and Statistics, Northwestern Polytechnical University, Xi’an 710129, China,   School of Mechanics, Civil Engineering and Architecture, Northwestern Polytechnical University, Xi’an 710129, China,   College of Science, Zhongyuan University of Technology, Zhengzhou 450007, China,   MIIT Key Laboratory of Dynamics and Control of Complex Systems, Xi’an 710072, China
Published: December 2020

The autaptic structure of neurons has the function of self-feedback, which is easily disturbed due to the quantum characteristics of neurotransmitter release. This paper focuses on the effect of conductance disturbance of chemical autapse on the electrophysiological activities of FHN neuron. First, the frequency encoding of FHN neuron to periodic excitation signals exhibits a nonlinear change characteristic, and the FHN neuron without autapse has chaotic discharge behavior according to the maximum Lyapunov exponent and the sampled time series. Secondly, the chemical autaptic function can change the dynamics of FHN neuronal system, and appropriate autaptic parameters can cause the dynamic bifurcation, which corresponds to the transition between different periodic spiking modes. In particular, the self-feedback function of chemical autapse can induce a transition from a chaotic discharge state to a periodic spiking or a quasi-periodic bursting discharge state. Finally, based on the quantum characteristics of neurotransmitter release, the effect of random disturbance from autaptic conductance on the firing activities is quantitatively studied with the help of the discharge frequency and the coefficient of variation of inter-spike interval series. The numerical results show that the disturbance of autaptic conductance can change the activity of ion channels under the action of self-feedback, which not only improves the encoding efficiency of FHN neuron to external excitation signals, but also changes the regularity of neuronal firing activities and induces significant coherent or stochastic bi-resonance. The coherent or stochastic bi-resonance phenomenon is closely related to the dynamic bifurcation of FitzHugh-Nagumo(FHN) neuronal system, and its underlying mechanism is that the disturbance of autaptic conductance leads to the unstable dynamic behavior of neuronal system, and the corresponding neuronal firing activity may transit between the resting state, the single-cycle and the multicycle spike states, thereby providing the occurring possibility for coherent or stochastic bi-resonance. This study further reveals the self-regulatory effect of the autaptic structure on neuronal firing activities, and could provide theoretical guidance for physiological manipulation of autapses. In addition, according to the pronounced self-feedback function of autaptic structure, a recurrent spiking neural network with local self-feedback can be constructed to improve the performance of machine learning by applying a synaptic plasticity rule.
Transparent conductive oxide film with antireflective properties for Cu2ZnSnS4 solar cells
Authors: Jing Jing , Li Zhi-Peng , Lu Wei-Sheng , Wang Hong-Yu , Yang Zu-An , Yang Yi , Yin Qi-Sheng , Yang Fu-Ling , Shen Xiao-Ming , Zeng Jian-Min , Zhan Feng ,   Key Lab of New Processing Technology for Nonferrous Metal and Materials of the Ministry of Education, Guangxi University, Nanning 530004, China,   CITIC Dameng Mining Industries Limited, Nanning 530028, China,   Zynergy Technology Incorporation, Fremont 94538, USA
Published: December 2020

At present, there are several kinds of broadband antireflection coatings (ARCs). For the flat multilayer ARC, it usually contains double, triple, or up to 4 layers. It has been demonstrated that the performance of a single layer coating is not good enough across the desired spectral range. Multiple layer ARCs have much better performance for broadband solar cells (SCs). When inspecting the antireflection structure of Cu2ZnSnS4 solar cells (CZTSSCs), it is shown that the transparent conductive oxide (TCO) of traditional CZTSSCs does not have an satisfactory antireflective performance. This paper aims to investigate a way to increase the incident light transmitted into CZTSSCs, and thus improving the efficiency of solar cells by studying the use of the antireflective effect of a TCO film. It introduces a new type of TCO film with better antireflective properties across a wide wavelength range. An SiO2/ZnO antireflective TCO (ATCO) is designed under AM1.5 illumination. In order to measure the antireflective effect over the 300–800 nm wavelength range, an effective average reflectance method (EAR) is introduced. Considering the effect of the refractive index dispersion and the coupling of the TCO or ATCO films with the active layer, in this paper we use a multi-dimensional transfer matrix to optimize the thickness of each key layer to accurately confirm the best antireflective effect. In addition, the optimized TCO film and the optimized ATCO film in CZTSSCs are compared and analyzed by means of EAR. The result shows, through the comparison of the antireflection between conventional TCO CZTSSCs and ATCO CZTSSCs, that there are considerable differences in final optimal reflectivity between TCO layer and ATCO film. For the conventional CZTSSC, the optimal effective average reflectance of TCO layer is 5.6%, and the lowest reflectivity in the waveband from 400 nm to 500 nm is 6.9%. In addition, the corresponding values obtained in the new ATCO CZTSSC are 3.8% and 1.6% respectively. These apparent changes in reflectivity are appealing in that the new ATCO films can effectively reduce light loss and improve the efficiency of photovoltaic conversion.
Piezoelectricity—An important property for ferroelectrics during last 100 years
Authors: Li Fei , Zhang Shu-Jun , Xu Zhuo ,   Electronic Materials Research Laboratory, Key Laboratory of the Ministry of Education, Xi’an Jiaotong University, Xi’an 710049, China,   Australian Institute of Advanced Materials, Wollongong University, Wollongong, NSW 2500, Australia
Published: December 2020

As an important member of the dielectric family, ferroelectric materials are known for their various physical properties and have been attracted considerable attention from both scientific respect and technology respect. Piezoelectricity is one of the most important properties of ferroelectrics, which has been widely used in many devices for the conversion between electric energy and mechanical energy. For example, the main piezoelectric elements of underwater acoustic transducers, medical imaging systems, piezoelectric actuators, etc., are all ferroelectrics. In this paper, the history of the piezoelectric effect in lead-based perovskite ferroelectrics is introduced, and the relationship among the microstructure, the state of polarization and the piezoelectricity is discussed. In addition, we introduce some important factors for optimizing the piezoelectricity of ferroelectrics, such as morphotropic phase boundary, soft doping, polarization rotation, local structural heterogeneity, etc. It is expected that this paper could shed light on the future design of ferroelectric materials with various functionalities.
Design and research of non-contact triboelectric nanogenerator based on changing electrostatic field
Authors: Cao Jie , Gu Wei-Guang , Qu Zhao-Qi , Zhong Yan , Cheng Guang-Gui , Zhang Zhong-Qiang ,   Institute of Intelligent Flexible Mechatronics, Jiangsu University, Zhenjiang 212013, China
Published: December 2020

Triboelectric nanogenerator (TENG) and its self-powered sensor based on the principles of contact electricity generation and electrostatic induction have important application prospects in the fields of new energy and internet of things (IoT). In the contact separation process of polymer materials with different electronegativity values, due to the transfer of electrons, a changing electrostatic field will be generated in the space around the polymer. In the existing TENG research, the field strength perpendicular to the plane of the friction layer and the electrode layer is mainly used to generate electrostatic induction, and the electric field effect around the polymer is ignored. According to the principle of electrostatic induction, the internal charge of the conductor in the electric field will be redistributed, which provides a way for the conductor to generate an induced electrical signal on the surface of the conductor without contacting the friction material. In this paper, we design a non-contact triboelectric nanogenerator (NC-TENG) based on changing electrostatic field. The influence of the distance between the conductor and the friction material, the induction area of the conductor and the position of the conductor relative to the friction material on the induced electrical output performance are studied when silicone rubber and nitrile rubber are used as a friction material. The results show that the NC-TENG can produce a stable electrical signal output when the conductor is completely separated from the friction material. The induced voltage of NC-TENG decreases with the increase of the distance between the conductor and the friction material, and gradually increases with the increase of the conductor's induction area. For the friction material with a size of 30 mm × 30 mm, the electrical output of NC-TENG tends to be stable when its conductor area is 60 mm × 45 mm. In addition, the different orientation of the conductor relative to the friction material also has a significant effect on the induced electrical output. The NC-TENG designed in this paper provides a novel electrical output generation mode, which provides a higher possibility for the subsequent research on TENG and the application of self-powered sensors.
Technical analysis of low-concentration airborne 134Cs, 137Cs, 103Ru and other radionuclides in Northern Europe in June 2020
Authors: Wang Shi-Lian , Li Qi , Zhao Yun-Gang , Zhang Xin-Jun , Fan Yuan-Qing , Wang Xiao-Ming , Jia Huai-Mao , Chen Zhan-Ying , Liu Shu-Jiang , Chang Yin-Zhong , Shi Jian-Fang ,   CTBT Beijing National Data Centre and Beijing Radionuclide Laboratory, Beijing 100085, China
Published: December 2020

On 22 June 2020, the trace amount of 134Cs, 137Cs and 103Ru in the atmosphere were detected by RN63 radionuclide station (in Sweden) of the International Monitoring System (IMS) for the Comprehensive Nuclear-Test-Ban Treaty (CTBT). Finland and Estonia declared the observation of these radionuclides and 141Ce, 95Zr and 95Nb respectively from 14 to 22 June 2020. Regarding the source term of the detection, various views all over the world were expressed on the networks. In this paper, these radionuclides and their activity concentrations are analyzed, and the nature of the detective event is determined through the analysis of these monitored data and the historical monitored data of each station. In addition, the release time of these radionuclide is estimated, and possible source term regions are obtained by using an atmospheric transport model. The results show that the activity ratio of 134Cs to 137Cs is about 1.10, which can exclude the possibility that the radionuclides detected come from nuclear test or nuclear explosion. The detection of 131I and 133I at the IMS RN61 station may be related to the small defection of reactor fuel assembly, and correlated temporally with the detection of 133Xe at the IMS RN49 station. Preliminary conclusions indicate that the 134Cs, 137Cs and 103Ru are likely to be related to the release of improper handling of reactor maintenance or fresh spent fuel transfer in Northern Europe region. Furthermore, due to the activity concentration is only μBq/m3 order of these radionuclides, it has no effect on public health.
Research progress of two-dimensional interlayer-sliding ferroelectricity
Authors: Zhong Ting-Ting , Wu Meng-Hao ,   Department of Physics, Zhejiang Sci-Tech University, Hangzhou 310018, China,   School of Physics, Huazhong University of Science and Technology, Wuhan 430074, China
Published: December 2020

In recent years, the existence of ferroelectricity in a series of two-dimensional van der Waals materials has been experimentally confirmed, in which the ferroelectricity induced by interlayer sliding is an important type. This mechanism is not available in traditional ferroelectrics but can be applied to many two-dimensional materials. In this paper we review the relevant researches and introduce the origin of this type of ferroelectricity: in many two-dimensional van der Waals bilayers, the upper layer is not equivalent to the lower layer, thus giving rise to a net interlayer charge transfer and the inducing vertical polarization to be switchable via interlayer sliding. This unique sliding ferroelectricity can widely exist in many van der Waals bilayers, multilayers and even bulk structures. The interlayer sliding barrier is several orders of magnitude lower than that of traditional ferroelectric, which may greatly save the energy required by ferroelectric switching. At present, this type of interlayer sliding ferroelectricity has been experimentally confirmed in WTe2 and β-InSe bilayer/multilayer systems, and more systems predicted to be with much stronger interlayer sliding ferroelectricity (like BN) may be realized in near future.
Classification of benign and malignant breast masses using entropy from nonlinear ultrasound radiofrequency signal
Authors: Zhang Mei-Mei , Gao Fan , Tu Juan , Wu Yi-Yun , Zhang Dong ,   Key Laboratory of Modern Acoustics of the Ministry of Education, School of Physics, Nanjing University, Nanjing 210093, China,   Department of Ultrasound, Jiangsu Provincial Hospital of Chinese Medicine, Nanjing 210029, China
Published: December 2020

In this paper the classification of benign and malignant breast masses is investigated by using the entropy of nonlinear ultrasound radio frequency (RF) signal. The parameters (entropy and weighted entropy) derived from the nonlinear ultrasound RF signal and the conventional ultrasound parameters (image grayscale, aspect ratio, irregularity, breast mass size, and depth) are extracted from 306 image samples (158 benign and 148 malignant); t-test and linear-discriminant classifier (LDC) are used to test the distinction between benign and malignant breast masses by each parameter; furthermore the effective parameters are combined to classify benign and malignant breast masses. The results show that except the image grayscale, the other parameters are significantly different between benign and malignant breast masses. Multi-parameter combined with support vector machine (SVM) is used to classify breast masses as benign and malignant. The accuracy is 81.4%, the sensitivity is 78.4%, and the specificity is 84.2%. The present work shows that the combination of the nonlinear entropy of ultrasound RF signal and traditional ultrasound parameters can more effectively characterize the benign and malignant breast masses. The entropy of nonlinear ultrasound RF signal can become a new parameter for characterizing the benign and malignant breast masses.
Soil Mechanical Composition and Texture as Indices for On-site and Field Precise Choice of Land Use Type to Adopt
Authors: Eyong M. O. , Ofem K. I.
Published: December 2020

The soils of Agoi-Ibami in central Cross River State of Nigeria were evaluated for their mechanical and textural compositions in the field. The objective was to present to small scale, subsistence farmers, with limited access to external farm-inputs for time consuming and expensive laboratory analysis, soil data for on-site and field land use and management decisions. Three profile pits were sunk, along three well defined and selected toposequences, on three landscape elements of crest, middleslope and valley bottom in three land use types of forest (FS), rubber (RS), and arable (AS). Relevant environmental properties were inventorized and the profiles described in the moist state. Their textures were determined by the feel method in the field among other morphological properties. The field investigation showed the soils to be predominatly loamy soils. After the field investigation, soil samples were collected from the morphogenetic horizons for determination of their mechanical composition in the laboratory to supplement the field investigation. Their loamy textures and mechanical composition inferred from their loamy texture impact unique physical and chemical properties like good water holding capacity, good drainage, fertile and productive soils and good for irrigation. Loamy soils exhibit properties intermediate between sandy and clayey soils. Loamy soils are considered best for agricultural production because they hold more water and nutrients than sandy soils and have better drainage, aeration and tillage properties than clayey soils. They have slight plastic and sticky workable properties ideal for crop growth and crop productivity. Therefore knowing the texture of soils and their mechanical composition in the field their properties can be inferred and land use and management decisions can be taken on-site without recourse to expensive and time consuming laboratory analyses which are beyond the capacity of resource poor small-scale and subsistence farmers in developing countries and or sub-Saharan Africa. The land use and management decisions are taken after mutual adaptation and adjustments of the description of the land use and the increasingly known soil qualities in the field.
A Logit Analysis of the Factors Affecting Cage Fish Farming Adoption Decisions in the Southwest Coast of India
Authors: Aswathy N. , Joseph Imelda
Published: December 2020

Aims: Cage fish farming is an emerging aquaculture technology in India. The successful cage farming demonstrations is the open sea and coastal waters by the ICAR-Central Marine Fisheries Research Institute (CMFRI) led to the popularization of the technology in different maritime states of the country. The aim of the study was to analyse  the factors contributing the adoption decisions of cage fish farming in Kerala, Southwest coast of India

Study Design:  The data were collected from 100 respondents consisting of 50 each from adopters and non-adopters of cage fish farming in Ernakulam district of Kerala for analyzing the factors driving the adoption decisions.

Place and Duration of Study: The study was conducted in Ernakulam district in the Southwest coast of India during October to December, 2019

Methodology: Factors contributing the adoption decisions of cage fish farming was analyzed using logistic regression model

Results: The results of the analysis revealed that access to institutional credit, education of the farmers, off farm income and training received were the key drivers of technology adoption decisions of fish farmers in Kerala. The odds favouring education increased by 5.90 times for the respondents. The access to institutional credit increased the odds of adoption of cage farming by 3.945 times. The availability of off farm income increased the odds of adopting cage farming technology by 3.257 times.

Conclusion: Cage fish farming being an emerging aquaculture technology, the results throw light on the necessity of adequate provisions for credit support and capacity development programmes by the institutional agencies for accelerating the technology adoption process. Since the education of the farmers and trainings were significant factors on adoption decisions, the technology could be effectively utilized and linked with employment generation schemes for the educated youth for augmenting fish production and livelihoods.
Resource Recycling for Farm Productivity and Profitability in Integrated Farming System under Rainfed Situation in Odisha, India
Authors: Sahoo Hemanta Kumar , Phonglosa Amit , Behera Basudev
Published: December 2020

The present investigation was carried out in 0.8 ha rainfed farm from April 2010 to March 2013 with two sources of water i.e. no pond/rainfed and pond/irrigated in five different blocks viz., Khajuripada of Kandhamal district (North Eastern Ghats Zone), Dhenkanal Sadar and Odapada of Dhenkanal district (Mid Central Table Land Zone), Golamunda and Narla of Kalahandi district (Western Undulating Zone) of Odisha. The 0.8 ha Integrated Farming System (IFS) model farm recorded 31.92 q Rice Equivalent Yield (REY) which was 7.4 times higher productivity than conventional rice-greengram system. The net return in IFS model was Rs. 1,61,148/- as compared to Rs. 11,631/- in conventional rice-greengram cropping system. The recyclable wastes of 3.3 t paddy straw, 3000 kg pond silt, 2129 kg poultry excreta and 13 t mushroom spent in IFS model were used as input by other units. Due to efficient recycling of wastes, the productivity and profitability of IFS models were higher compared to conventional cropping system. Thus, almost no waste was left to pollute the environment or to degrade the resource base where as the wastes in conventional system were not utilized effectively.
Effect of Hydrocolloid Carboxymethyl Cellulose (CMC) on Clarification of Bottle Gourd Juice and Its Physicochemical Properties
Authors: Ashraf Aafaq , Ayoub Anjum , Dixit Ashish
Published: December 2020

Effectiveness of the Hydrocolloid Carboxymethyl Cellulose (CMC) on Bottle Gourd Juice was investigated in this study. The influence of carboxymethyl cellulose (CMC) on the colloidal stability of cloudy Bottle Gourd juice has been studied. Concentrations of CMC from 0.1–0.4% completely inhibited juice clarification. Juices with CMC were more stable.Characterization of rheology is important for clarification of the product and storage.Use of hydrocolloid was only to enhance viscosity and creating gel structure of juice.Temperatures ranging from 5-35ºC were used in carrying out the experiments . The purpose of this research was to study the clarification, quality improvement and shelf life of Bottle gourd juice.
What a Clinical Hematologist Should Know about T Cells?
Authors: Sharma Sanjeev Kumar
Published: December 2020

T cell’s journey begins from the bone marrow and ends in the peripheral tissues by either fighting the infections or residing in the secondary lymphoid organs as memory T cell. Thymus plays most important role in transforming a docile T cell precursor into a warrior. T cell is one of the most important cells in health and disease. Various diseases originate from qualitative or quantitative defects in T cells leading to various inherited and acquired diseases. This simple and short review is focused on the basic understanding and clinical hematologist’s perspective of T cells.
Soil Fertility Evaluation and GPS-GIS Based Soil Nutrient Mapping of Krishi Vigyan Kendra, Palem, Telangana
Authors: Rajamani Kasthuri , Hari N. , Rajashekar M.
Published: December 2020

Soil fertility evaluation of an area is an important aspect in the context of sustainable agriculture production. In the present investigation KVK, Palem farm was selected in the district Nagarkurnool of Telangana and studied physico-chemical, available macro and micronutrient status using Nutrient Index approach made with the study of 60 surface soil samples and were analyzed for pH, Electrical Conductivity (EC), Organic Carbon (OC), Nitrogen (N), Phosphorus (P), Potassium (K) and micronutrients (Fe, Mn, Cu and Zn). Study results indicated that a major proportion of area soils are neutral (62.08%) and non-saline (100%). The whole study area was low in organic carbon content, ranging from 0.40 to 0.45 with a mean of 0.42%, and available nitrogen also low in the entire study area varied from 150.53 to 188.16 kg ha-1 with a mean value of 165.67 kg ha-1. The percent distribution of available P varied from medium to high status (34.48 and 72.41%), where available K was categorized under high (100%) status. With regard to micronutrients, the soils were predominantly deficient in Zn (24.13%) followed by Fe (20.68%) and Mn (6.89%).
The Investigation of Antimutagenic Effects on Chromosomes and Cell Division Mechanisms against Mitomycine C in Human Lymphocyte Culture of Liquid Extracts Obtained from Blueberry (Vaccinium myrtillus L.) and Raspberry (Rubus idaeus L.)
Authors: Kaya Müge Mavioğlu , Gül Süleyman
Published: December 2020

Aims: In this study, we determined that whether the liquid extracts of the above-ground parts of Vaccinium myrtillus L. and Rubus idaeus L. have antimutagenic effects against mitomycin C in human peripheral lymphocytes, chromosome aberration (CA), micronucleus (MN) and mitotic index (MI) tests.

Methodology: Blood samples of the negative control group (Group I) were allowed to react in a cell culture medium without any treatment, while positive control group (Group II) was allowed to interact in a cell culture medium supplemented with mitomycin-C (MMC) at a dose of 0.3 μL /mL for each chromosome medium. Blood samples of the other groups were allowed to react for 24 hours with 0.3 μL /mL MMC and V. myrtillus L. (Group III, IV, V and VI), and R. idaeus L. (VII, VIII, IX and X) extracts in 0.2 μL /mL, 0.4 μL /mL, 0.8 μL /mL and 1.6 μL /mL doses for each of cell cultures. At the end of the incubation period, culture cells were evaluated by chromosomal aberrations, mitotic, micronucleus and nuclear division index tests.

Results: Compared with Group II, it was determined that mitotic, nuclear division and nuclear cytotoxic cleavage indices were increased when chromosome aberrations and micronucleus indexes were decreased in extract groups. When we compared to extract groups and group II, we observed that chromosome aberrations and micronucleus index decreased in extract groups, while mitotic, nuclear division and nuclear cytotoxic cleavage indices were increased.

Conclusion: It was concluded that aqueous extracts of V. myrtillus L. and Rubus idaeus L. had significantly antimutagenic effects on the human peripheral lymphocyte cells at the working doses.
Retrospective Study of Investigation of Possible Predictors for Total Fertility Rate in India
Authors: Tiwari A. K. , Singh Brijesh P. , Patel Vaishali
Published: December 2020

Total fertility rate (TFR) is the most acceptable and widely used measure of current fertility. Since TFR is based on age-specific fertility rate which required the total number of births in different age groups as well as age of female. When the population is illiterate or older then the information on age may have some recall bias, misreporting digit preference etc., thus in this situation TFR may departed from the actual. Therefore, need some indirect methodology which enables us to have an idea about the estimation of TFR. In this study an attempt has been made to identify some predictors that the explain TFR and try to suggest the best combination of predictors to get estimate of TFR. The methodology used in this study is essentially based on the regression technique. The identification and acceptance of possible predictors are based on the coefficient of determination. The data for the major states of India from National Family Health Survey (NFHS 4) is used for the analysis.
First Decade of Interfacial Iontronic Sensing: From Droplet Sensors to Artificial Skins
Authors: Chang Yu , Wang Liu , Li Ruya , Zhang Zhichao , Wang Qi , Yang Junlong , Guo Chuan Fei , Pan Tingrui
Published: December 2020

Over the past decade, a brand‐new pressure‐ and tactile‐sensing modality, known as iontronic sensing has emerged, utilizing the supercapacitive nature of the electrical double layer (EDL) that occurs at the electrolytic–electronic interface, leading to ultrahigh device sensitivity, high noise immunity, high resolution, high spatial definition, optical transparency, and responses to both static and dynamic stimuli, in addition to thin and flexible device architectures. Together, it offers unique combination of enabling features to tackle the grand challenges in pressure‐ and tactile‐sensing applications, in particular, with recent interest and rapid progress in the development of robotic intelligence, electronic skin, wearable health as well as the internet‐of‐things, from both academic and industrial communities. A historical perspective of the iontronic sensing discovery, an overview of the fundamental working mechanism along with its device architectures, a survey of the unique material aspects and structural designs dedicated, and finally, a discussion of the newly enabled applications, technical challenges, and future outlooks are provided for this promising sensing modality with implementations. The state‐of‐the‐art developments of the iontronic sensing technology in its first decade are summarized, potentially providing a technical roadmap for the next wave of innovations and breakthroughs in this field.
Electrochemiluminescent Transistors: A New Strategy toward Light‐Emitting Switching Devices
Authors: Lee Seonjeong , Lee Han Ju , Ji Yena , Lee Keun Hyung , Hong Kihyon
Published: December 2020

Light‐emitting transistors (LETs) have attracted a significant amount of interest as multifunctional building blocks for next‐generation electronics and optoelectronic devices. However, it is challenging to obtain LETs with a high carrier mobility and uniform light‐emission because the semiconductor channel should provide both the electrical charge transport and optical light‐emission, and typical emissive semiconductors have low, imbalanced carrier mobilities. In this work, a novel device platform that adapts the electrochemiluminescence (ECL) principle in LETs, referred to as an ECL transistor (ECLT) is proposed. ECL is a light‐emission phenomenon from electrochemically excited luminophores generated by redox reactions. A solid‐state ECL electrolyte consisting of a network‐forming polymer, ionic liquid, luminophore, and co‐reactant is employed as the light‐emitting gate insulator of the ECLT. Based on this construction, high‐performance LETs that make use of various conventional non‐emissive semiconductors (e.g., poly(3‐hexylthiophene), zinc oxide, and reduced graphene oxide) are successfully demonstrated. All the devices exhibit a high mobility (0.9–10 cm2 V−1 s−1) and a uniform light‐emission. This innovative approach demonstrates a novel LET platform and provides a promising pathway to achieve significant breakthroughs to develop electronic circuits and optoelectronic applications.
Room‐Temperature Phosphorescence Enabled through Nacre‐Mimetic Nanocomposite Design
Authors: Yao Xuyang , Wang Jie , Jiao Dejin , Huang Zizhao , Mhirsi Oumaima , Lossada Francisco , Chen Lisa , Haehnle Bastian , Kuehne Alexander J. C. , Ma Xiang , Tian He , Walther Andreas
Published: December 2020

A generic, facile, and waterborne strategy is introduced to fabricate flexible, low‐cost nanocomposite films with room‐temperature phosphorescence (RTP) by incorporating waterborne RTP polymers into self‐assembled bioinspired polymer/nanoclay nanocomposites. The excellent oxygen barrier of the lamellar nanoclay structure suppresses the quenching effect from ambient oxygen (kq) and broadens the choice of polymer matrices towards lower glass transition temperature (Tg), while providing better mechanical properties and processability. Moreover, the oxygen permeation and diffusion inside the films can be fine‐tuned by varying the polymer/nanoclay ratio, enabling programmable retention times of the RTP signals, which is exploited for transient information storage and anti‐counterfeiting materials. Additionally, anti‐interception materials are showcased by tracing the interception‐induced oxygen history that interferes with the preset self‐erasing time. Merging bioinspired nanocomposite design with RTP materials contributes to overcoming the inherent limitations of molecular design of organic RTP compounds, and allows programmable temporal features to be added into RTP materials by controlled mesostructures. This will assist in paving the way for practical applications of RTP materials as novel anti‐counterfeiting materials.
A Wind‐Driven Poly(tetrafluoroethylene) Electret and Polylactide Polymer‐Based Hybrid Nanogenerator for Self‐Powered Temperature Detection System
Authors: Zhang Jinxi , Gong Shaobo , Li Xin , Liang Junrui , Wang Zhong Lin , Ren Kailiang
Published: December 2020

With growing interest in artificial intelligence and the Internet of Things, self‐powered electronics have gained considerable attention. In this investigation, a wind‐driven hybrid nanogenerator system comprising a poly(l‐lactic acid)‐based piezoelectric nanogenerator and a poly(tetrafluoroethylene) electret‐based triboelectric nanogenerator (E‐TENG) is proposed. At a wind speed of 5.1 m s−1, the open‐circuit voltage (Voc) and short‐circuit current (Isc) of the hybrid nanogenerator (NG) reach ≈140 V and 16 µA, respectively. The maximum output power of the hybrid NG reaches ≈0.49 mW with a matching resistance of 8 MΩ, which is 22% larger than the output power of the E‐TENG. The hybrid NG can charge a lithium battery to 2.9 V in 8 h. Furthermore, the charged battery can be employed to drive an IR remote controlled light‐emitting diode lamp and turn the lamp on and off. In addition, it can be combined with a Bluetooth low energy (BLE) temperature sensor to form a self‐powered BLE temperature detection system. The hybrid NG shows great promise in self‐powered environmental monitoring and detection applications.
Genetics influence postharvest measurements of flue‐cured tobacco more than nitrogen application rate
Authors: Cheek Joseph A. , Vann Matthew C. , Lewis Ramsey S. , Fisher Loren R.
Published: December 2020

Regulations under consideration by the U.S. Food and Drug Administration and the World Health Organization propose that nicotine concentration in tobacco (Nicotiana tabacum L.) should be lowered to non‐addictive levels (0.3 to 0.5 mg g−1). The proposed standards are 90 to 95% lower than the nicotine concentration typically documented in commercially available cultivars. Research was conducted in six environments to evaluate two cultivars with normal alkaloid levels (K326 and NC95) and four genotypes with low alkaloid levels (DH16A, DH22A, DH32, and LAFC53). Each cultivar and genotype was paired with three N application rates: 70, 85, and 100% of the recommended rate. As N application declined, so too did cured leaf yield and nicotine, anabasine, and anatabine concentration in K326 and NC95. These factors were generally not affected by N application in the low alkaloid genotypes. In contrast, LAFC53 consistently produced the lowest cured leaf quality, value, and reducing sugar concentration when compared to all other cultivars. This observation demonstrates that K326 isolines are agronomically superior to LAFC53. Despite reductions in nicotine, the lowest documented concentration was still 10‐fold greater than the proposed minimum (LAFC53). Nitrogen did not influence the measured parameters as much as genetics; therefore, additional research that involves other agronomic practices is warranted. In addition, further genetic manipulation will be required to meet the standards proposed by regulatory groups.
Positively Charged and pH‐sensitive Carbon Dots for Fluorescence Detection of Copper Ion
Authors: Feng Feng , Miao Chenfang , Zhang Yalan , Huang Zhengjun , Weng Shaohuang
Published: December 2020

As an essential trace element in the human body, copper ion (Cu2+) performs an important role in many fundamental physiological processes that need a facile and effective method for the monitoring of Cu2+ in organisms. Herein, a turn‐off, facile fluorescent strategy for sensing Cu2+ was proposed using positively charged carbon dots (P‐CDs) as probe. The P‐CDs prepared from melting strategy exhibited stable, biocompatible, and pH‐sensitive luminescent properties. P‐CDs can be selectively quenched by Cu2+ for the direct detection of Cu2+. The reaction mechanism between Cu2+ and P‐CDs was systematically investigated, illustrating that Cu2+ coordinated with the surface functional groups in P‐CDs. The binding effect of Cu2+ and P‐CDs caused the constant morphology and static quenching behavior of P‐CDs. The promising accuracy of the testing results of the addition of Cu2+ in diluted serum using P‐CDs implied their extended application in the biological field.
Head and neck cancer surgery during the COVID‐19 pandemic: An international, multicenter, observational cohort study
Authors:   COVIDSurg Collaborative
Published: December 2020

Background

The aims of this study were to provide data on the safety of head and neck cancer surgery currently being undertaken during the coronavirus disease 2019 (COVID‐19) pandemic.

Methods

This international, observational cohort study comprised 1137 consecutive patients with head and neck cancer undergoing primary surgery with curative intent in 26 countries. Factors associated with severe pulmonary complications in COVID‐19–positive patients and infections in the surgical team were determined by univariate analysis.

Results

Among the 1137 patients, the commonest sites were the oral cavity (38%) and the thyroid (21%). For oropharynx and larynx tumors, nonsurgical therapy was favored in most cases. There was evidence of surgical de‐escalation of neck management and reconstruction. Overall 30‐day mortality was 1.2%. Twenty‐nine patients (3%) tested positive for severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2) within 30 days of surgery; 13 of these patients (44.8%) developed severe respiratory complications, and 3.51 (10.3%) died. There were significant correlations with an advanced tumor stage and admission to critical care. Members of the surgical team tested positive within 30 days of surgery in 40 cases (3%). There were significant associations with operations in which the patients also tested positive for SARS‐CoV‐2 within 30 days, with a high community incidence of SARS‐CoV‐2, with screened patients, with oral tumor sites, and with tracheostomy.

Conclusions

Head and neck cancer surgery in the COVID‐19 era appears safe even when surgery is prolonged and complex. The overlap in COVID‐19 between patients and members of the surgical team raises the suspicion of failures in cross‐infection measures or the use of personal protective equipment.

Lay Summary

Head and neck surgery is safe for patients during the coronavirus disease 2019 pandemic even when it is lengthy and complex.

This is significant because concerns over patient safety raised in many guidelines appear not to be reflected by outcomes, even for those who have other serious illnesses or require complex reconstructions.

Patients subjected to suboptimal or nonstandard treatments should be carefully followed up to optimize their cancer outcomes.

The overlap between patients and surgeons testing positive for severe acute respiratory syndrome coronavirus 2 is notable and emphasizes the need for fastidious cross‐infection controls and effective personal protective equipment.
A distributed system for supporting smart irrigation using Internet of Things technology
Authors: Abdelmoamen Ahmed Ahmed , Al Omari Suhib , Awal Ripendra , Fares Ali , Chouikha Mohamed
Published: December 2020

In this paper, we present the design and implementation of a smart irrigation system using Internet of Things (IoT) technology, which can be used for automating the irrigation process in agricultural fields. It is expected that this system would create a better opportunity for farmers to irrigate their fields efficiently, as well as eliminating the field's under‐watering, which could stress the plants. The developed system is organized into three parts: sensing side, cloud side, and user side. We used Microsoft Azure IoT Hub as an underlying infrastructure to coordinate the interaction between the three sides. The sensing side uses a Raspberry Pi 3 device, which is a low‐cost, credit‐card sized computer device that is used to monitor in near real‐time soil moisture, air temperature and relative humidity, and other weather parameters of the field of interest. Sensors readings are logged and transmitted to the cloud side. At the cloud side, the received sensing data is used by the irrigation scheduling model to determine when and for how long the water pump should be turned on based on a user‐predefined threshold. The user side is developed as an Android mobile app, which is used to control the operations of the water pump with voice recognition capabilities. Finally, this system was evaluated using various performance metrics, such as latency and scalability.