bluuebunny/crossref_metadata_2025 huggingface dataset:
Noise processing of superconducting kinetic inductance single photon detector
Authors: Huang Dian , Dai Wan-Lin , Wang Yi-Wen , He Qing , Wei Lian-Fu ,   Information Quantum Technology Laboratory, School of Information Science and Technology, Southwest Jiaotong University, Chengdu 610031, China,   Quantum Optoelectronics Laboratory, School of Physical Science and Technology, Southwest Jiaotong University, Chengdu 610031, China,   Photonics Laboratory, School of Science, Donghua University, Shanghai 201620, China
Published: June 2021

Noise is one of the main factors affecting the performance index of weak signal detection devices, and the optimal filtering algorithm is an effective method to adaptively extract various useful weak signals from the white noise background. In order to improve the performance of single photon detector (especially the photon number resolution ability), one mainly focuses on the optimization of detector hardware such as the optimization of photosensitive materials and the technology of device fabrication. However, in this paper the performance of microwave kinetic Inductance detector (MKID) in the way of data processing is improved. Considering the fact that the template of light pulse signal in the optimal filtering algorithm is obtained by taking the average, we replace the noise model in the original optimal filtering algorithm with the white noise model and the whitening noise model. Then we process the photon response data that are detected by the MKID in an extremely low temperature environment. The results show that the energy resolution (one of the main performance indexes of single photon detector) of MKID is improved by about 15%, and we achieve an infrared single photon energy resolution of 0.26 eV. In this paper, the application and development trends of superconducting single photon detector are briefed. Then, how the MKID responds to weak coherent optical signal in low temperature environment, and the process of signal conversion, acquisition and output are explained in detail. According to the optimal filtering algorithm, we use different noise models to analyze the results of the signals detected by MKID. After that, we count the optimal amplitude multiple, perform the Gaussian fitting analysis on the statistical graph, and compare the energy resolution with the photon number resolution of the optimal filtering algorithm under different noise models. As a result, we find that under the white noise model, the optimal filtering algorithm is used to obtain the best result for MKID processing, and high energy resolution can be achieved.
Simulation of displacement damage in indium phosphide induced by space heavy ions
Authors: Bai Yu-Rong , Li Yong-Hong , Liu Fang , Liao Wen-Long , He Huan , Yang Wei-Tao , He Chao-Hui ,   School of Nuclear Science and Technology, Xi’an Jiaotong University, Xi’an 710049, China
Published: June 2021

Indium phosphide (InP) has the characteristics of high electron mobility, large band gap, high temperature resistance, and radiation resistance. It is an important material of electronic devices in the space radiation environment. With the miniaturization of electronic devices, the displacement damage (DD) effect caused by a single heavy ion in the device may give rise to permanent failure. Therefore, this paper uses Monte Carlo software Geant4 to simulate the transportation process of space heavy ions(C, N, O, Fe) in InP. The non-ionizing energy loss (NIEL) of heavy ions is calculated for getting the information about displacement damage. Some conclusions are drawn as follows. 1) NIEL is proportional to the square of the atomic number, which means that single Fe can make severe displacement damage in InP. 2) The heavy ions NIEL is 3 to 4 orders of magnitude larger than PKA NIEL. The NIEL is proportional to the non-ionizing damage energy of recoil atoms produced by nuclear elastic collision, which indicates that the primary recoil atoms produced by heavy ions are the main cause of InP DD. 3) The number of heavy ions in space is small, so the proportion of total non-ionizing damage energy produced by heavy ions in 0.0125 mm3 InP is only 2.56% in one year. But the NIEL of heavy ions NIEL is 2–30 times that of protons and α particles, so the DD effect caused by single heavy ion incident on InP electronic device still needs to be considered. 4) NIEL decreases slightly with the increase of material thickness. The reason is that low-energy heavy ions are completely deposited in the front of InP, resulting in a non-uniform distribution of non-ionizing energy deposited in the material. Analyzing the dependence of mean DD energy with depth, we find that mean DD energy decreases with incident depth increasing, which means that the most severe DD region of heavy ions in InP is in the front of material.
Influence of water parameters on threshold value and gain coefficient of stimulated Brillouin scattering
Authors: Xu Jin , Guo Yang-Ning , Luo Ning-Ning , Li Shu-Jing , Shi Jiu-Lin , He Xing-Dao ,   School of Instrumentation and Optoelectronic Engineering, Beihang University, Beijing 100191, China,   Key Laboratory of Opto-Electronic Information Science and Technology of Jiangxi Province, Nanchang Hangkong University, Nanchang 330063, China
Published: June 2021

Stimulated Brillouin scattering (SBS) is a typical inelastic scattering effect generated by the interaction between intense incident laser and the acoustic wave field in medium and has always been an active research topic in nonlinear optics. The SBS can be used as a novel LIDAR technology for active optical remote sensing of temperature and sound speed structure in ocean. Although, the threshold value and gain property of SBS at normal temperature are studied, none of the threshold values and gain coefficients of SBS at different temperatures, pressures and attenuation coefficients has been investigated in detail. Further, neither the relation between threshold value and water pressure nor the relation between gain coefficient and water pressure is clear now, and little work has been reported. The theoretical and experimental studies of the influence of water parameters on the threshold value and gain coefficient of SBS are still scanty. In this paper, the effects of temperature, pressure and attenuation coefficient of water on threshold value and gain coefficient of SBS are studied theoretically and experimentally. Theoretically, the variations of threshold value and gain coefficient of SBS with temperature, pressure and attenuation coefficient are analyzed by the average attenuation coefficient method based on the distributed noise model (DNM) and coupled wave equations. The temporal waveforms of Stokes-, pump- and transmission-beam at different water parameters are obtained by using the DNM. Experimentally, a temperature-pressure controlled simulator is designed to obtain the threshold values and gain coefficients of SBS in water at different temperatures, pressures and attenuation coefficients through measuring the change of attenuation coefficient of laser pulses. The results indicate that (i) the threshold value of SBS increases with pressure increasing at the same temperature and decreases with temperature increasing at the same pressure; (ii) the threshold value is positively correlated with the attenuation coefficient at the same temperature and pressure; (iii) the gain coefficient of SBS increases with temperature increasing at the same pressure and decreases with pressure increasing at the same temperature. We also find that the temperature and attenuation coefficient have greater effect on threshold value and gain coefficient of SBS than the water pressure. The studied results are of great significance in realizing the ocean remote sensing by SBS lidar.
First-principles calculation of diamond/Al interface properties and study of interface reaction
Authors: Zhu Ping , Zhang Qiang , Gou Hua-Song , Wang Ping-Ping , Shao Pu-Zhen , Kobayashi Equo , Wu Gao-Hui ,   School of Materials Science and Engineering, Harbin Institute of Technology, Harbin 150001, China,   Key Laboratory of Advanced Structure-Function Integrated Materials and Green Manufacturing Technology, Harbin Institute of Technology, Harbin 150001, China,   Department of Materials Science and Engineering, Tokyo Institute of Technology, Tokyo 152-8550, Japan
Published: June 2021

First-principles calculation and experimental methods are used to study the interfacial properties and reaction of diamond/Al composites. Based on the first-principles method, the interfacial adhesion work (Wad), electronic structure and charge transfer of diamond/Al models are calculated systematically. The results show that the adhesion work of diamond(100)/Al(111) is 41% higher than that of diamond(111)/Al(111), therefore, the interface bonding of diamond(100)/Al(111) interface is stronger. According to the analysis of the electronic structure, there are more charges transferring at the diamond(100)/Al(111) interface, and the high charge density is distributed on the side of C atoms. The redistribution of charges at the interface is conducive to the formation of Al—C bond, so that the tendency of forming Al—C bonds is greater. The introduction of Al—C bond can promote the formation of C—C bond at the diamond(100)/Al(111) interface and improve the interfacial adhesion work. In addition, the diamond/Al composites are fabricated by vacuum gas pressure infiltration, and multi-scale characterization of the interface structure of diamond/Al composites is carried out. The interfacial debonding occurs mainly on the diamond {111}. Meanwhile, the interface product Al4C3 is easier to form on the diamond {100}. The experimental phenomenon is consistent with the calculated results. Moreover, the influence of the interfacial reaction on the properties and stability of diamond/Al composites are further discussed through heat-moisture treatment. The study finds that the performance degradation in heat-moisture environment is related mainly to the hydrolysis of the interface product Al4C3. After 60 days’ heat-moisture, the thermal conductivity of the diamond/Al composites decreases by 29.9%, and the bending strength is reduced by 40.1%. The large attenuation of performance is not conducive to the stability of composites in complex environments. Therefore, inhibiting the formation of Al4C3 and improving interfacial selectivity are of great importance in developing the performance and stability of diamond/Al composites. The research in this paper not only lays a theoretical foundation for the first-principles calculation of the interface properties of diamond/metal, but also possesses important guidance significance in designing the diamond/metal composites.
Nanoscale electromagnetic field interaction generated by microtubule vibration in neurons
Authors: Wang Yan-Hong , Wang Lei , Wu Jing-Zhi ,   School of Information and Communication Engineering, North University of China, Taiyuan 030051, China,   School of Chemical Engineering and Technology, North University of China, Taiyuan 030051, China
Published: June 2021

Neurons collect information from different parts of the biological body, generate signals and control their functions and activities. There are electromagnetic communication channels between neurons apart from the action potentials. Microtubules are the largest cytoskeletal filaments in neurons, with a diameter of about 25 nm. Microtubule is composed of alpha- and beta-tubulin subunits assembled into hollow cylindrical polymers supporting dynamical growth, and facilitate transport of proteins. In axons, dendrites, growth cones, and migratory neurons, microtubules are generally tightly organized in array and uniformly oriented. Because of the polarity and charge distribution of tubulins, the vibrations of microtubules generate electromagnetic fields. In this paper, electromagnetic fields induced by different vibrational modes of microtubules are studied. The vibrational mode of tubulins calculated using the normal mode analysis shows that there are abundant vibrational modes in the terahertz range. The electric fields of different vibration modes show distinct distribution features. The induced electromagnetic fields of microtubules can be stronger than thermal noise because of reduced permittivity of intracellular fluid for higher frequencies in a nanometric confined region. Since water exhibits layered structuring near all surfaces independent of their hydrophilicity, the permittivity of water surrounding tubulins between microtubules is expected to decrease significantly because of surface-induced alignment of water molecular dipoles. While the permittivity of surrounding medium decreases to 5, the electromagnetic potential energy between two 100-nm-long microtubules can be stronger than the thermal energy within a 30-nm-long distance. As high frequency vibrations are generally localized in the microtubule, terahertz electromagnetic interactions can be present between tubulins and short microtubules. Because the separation between microtubule arrays in neurons is in a range from 20 nm to 100 nm, electromagnetic interactions between microtubules can dominate the thermal motions, and affect the biological functions. Simulation results show that the electromagnetic potential energy increases over one order of magnitude when the vibration amplitude is changed from 0.1 nm to 0.4 nm. The results indicate that the electromagnetic interaction between microtubules is important for a better understanding of neural functions and communication. Terahertz stimulations can be used to detect and modulate the neural signals. The microtubule vibration generated magnetic field can be applied to disease diagnosis and brain-machine interface.
Optimization of pulsed intense magnetic field device for laser plasma experiment via inductively coupled coil
Authors: Zhao Jia-Yi , Hu Peng , Wang Yu-Lin , Wang Jin-Can , Tang Hui-Bo , Hu Guang-Yue ,   CAS Key Laboratory of Geospace Environment, Department of Engineering and Applied Physics, University of Science and Technology of China, Hefei, Anhui 230026, China,   CAS Center for Excellence in Ultra-intense Laser Science(CEULS), Shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, Shanghai 201800, China
Published: June 2021

Magnetized laser plasma has attracted a lot of attention in recent years especially in magnetized inertial confinement fusion, laboratory astrophysics, and industrial application. Pulsed intense magnetic field device is the core equipment of magnetized laser plasma experiment. Here in this work, an inductively coupled coil is developed to optimize the pulsed intense magnetic field device. The primary coil of a multi-turn solenoid is used instead of a single-turn coil. Then the energy of the solenoid is delivered to the secondary coil via inductively coupled transformer, which increases the current density markedly. The current generates a stronger magnetic field in the single-turn magnetic field coil. The influence of the diameter and the number of turns of the primary solenoid of the inductively coupled coil on the magnetic field are explored in experiment and simulation. It is found that for a discharge system of 2.4 μF capacitance, the optimized parameters of the primary solenoid are 35 turns and 35 mm diameter. The optimized magnetic field is 3.6 times stronger than that of the conventional directly connected single-turn coil. At a charging voltage of 20 kV, the peak magnetic field reaches 19 T in a magnetic field coil of 5 mm inner diameter. The inductively coupled coil made of CuBe solves the problem of coil expansion in intense magnetic field, and a peak magnetic field of 33 T is obtained at a charging voltage of 35 kV. The present approach creates stronger magnetic field environments. At the same time, the inductively coupled coil reduces the requirements for system inductance, so that components such as energy storage capacitors and switch can be placed far from the coil, which improves the flexibility of the experiment setup.
A new tunable weighting strategy for enhancing performance of network computation
Authors: Li Hui-Jia , Huang Zhao-Ci , Wang Wen-Xuan , Xia Cheng-Yi ,   School of Science, Beijing University of Posts and Telecommunications, Beijing 100876, China,   School of Computer and Communication Engineering, TianjinUniversity of Technology, Tianjin 300384, China
Published: June 2021

For many real world systems ranging from biology to engineering, efficient network computation methods have attracted much attention in many applications. Generally, the performance of a network computation can be improved in two ways, i.e., rewiring and weighting. As a matter of fact, many real-world networks where an interpretation of efficient computation is relevant are weighted and directed. Thus, one can argue that nature might have assigned the optimal structure and weights to adjust the level of functionality. Indeed, in many neural and biochemical networks there is evidence that the synchronized and coordinated behavior may play important roles in the system’s functionality. The importance of the network weighting is not limited to the nature. In computer networks, for example, designing appropriate weights and directions for the connection links may enhance the ability of the network to synchronize the processes, thus leading the performance of computation to improve. In this paper, we propose a new two-mode weighting strategy by employing the network topological centralities including the degree, betweenness, closeness and communication neighbor graph. The weighting strategy consists of two modes, i.e., the original mode, in which the synchronizability is enhanced by increasing the weight of bridge edges, and the inverse version, in which the performance of community detection is improved by reducing the weight of bridge edges. We control the weight strategy by simply tuning a single parameter, which can be easily performed in the real world systems. We test the effectiveness of our model in a number of artificial benchmark networks as well as real-world networks. To the best of our knowledge, the proposed weighting strategy outperforms previously published weighting methods of improving the performance of network computation.
Test study of detector modules based on monolithic active pixel sensor
Authors: Yang Sheng-Hui , Dong Ming-Yi , Qu Chao-Yue , Tian Xing-Cheng , Dong Jing , Wu Ye , Ma Xiao-Yan , Zhang Hong-Yu , Jiang Xiao-Shan , Ouyang Qun , Li Lan-Kun , Zheng Guo-Heng ,   School of Physics and Microelectronics, Zhengzhou University, Zhengzhou 450001, China,   State Key Laboratory of Particle Detection and Electronics, Institute of High Energy Physics, Chinese Academy of Sciences, Beijing 100049, China,   University of Chinese Academy of Sciences, Beijing 100049, China
Published: June 2021

Silicon pixel detectors are widely used as vertex detectors or inner trackers in high-energy collider experiments because of their excellent spatial resolution, extremely high counting capability and low power consumption. The study of the silicon pixel detector based on the monolithic active pixel sensor (MAPS) is one of the R&D schemes for upgrading the inner chamber of the Beijing spectrometer Ⅲ (BESⅢ) drift chamber (MDC). It is planned to build a 1/10 scale prototype of the inner chamber. The detector module is the basic component of the prototype, consisting of ten MIMOSA28 chips thinned to 50 μm, a flexible cable and a carbon fiber support. In order to study the performance of the module, a test system is set up. The system is composed mainly of five-layer modules, readout electronics and data acquisition system. This article focuses on the realization of the continuous data readout method with trigger marking function, the measurement of the noise level of the detector modules, the module response test by a radioactive source, and the study of the hit reconstruction algorithm. The test of trigger readout logic verifies the correctness of the continuous readout method with trigger marking. It can be concluded that analyzing consecutive three frames data (the previous frame, the current frame and the next frame) of each valid trigger will not lead to effective hit data loss. The noise level of the detector module is tested. The results show that the fixed pattern noise (FPN) is 0.253 mV, and the temporal noise (TN) is 1.65 mV. The fake hit rate is less than \begin{document}$ {10}^{-5} $\end{document} that can be ignored when the chip threshold is set to be above 4σ of noise. Two algorithms for hit reconstruction (i.e. adjacent method and comparison method) are studied and compared. When the average number of fired pixels caused by each hit is 2.562 and more than four hits in each frame of data, the adjacent method can find all of the fired pixels to be faster. During the test, the detector module and the electronics are proved to work well. These studies lay a foundation for further testing the performance of the detector prototype.
Single-molecule study of interaction between melittin and one-component lipid membrane
Authors: Wang Kang , Xu Cheng , Wu Jin-Feng , Yang Kai , Yuan Bing ,   Center for Soft Condensed Matter Physics and Interdisciplinary Research, School of Physical Science and Technology, Soochow University, Suzhou 215006, China
Published: June 2021

In recent years, the emergence and development of single-molecule tracking technology has provided a new way to study the biological process in a cell membrane. However, the heterogeneity of biomolecular motions in cell membranes makes it difficult to distinguish and separate different molecular motion patterns from a large number of molecular trajectories. In this work, taking the system of interaction between melittin and a single-component supported phospholipid bilayer (SLB) membrane as an example, a type of data analysis method is developed through using the frequency distribution of standard deviations of single molecular motion displacements to distinguish and separate lipid molecules in different motion modes. It provides higher accuracy and more quantitative information than traditional analysis methods based on the frequency distribution of displacement or radius of gyration. By using this method, we successfully separate the two moving states of lipids in the SLB, and find that such a distribution is partly consistent with the location distribution of lipids in the upper leaflet and lower leaflet. Under the influence of surface adsorption or transmembrane poration of melittin at different concentrations, the movements of these two types of lipids are disturbed in different ways. In this work, a data analysis method for the separation of molecular motion patterns is developed according to the complex heterogeneity of molecular motions in a phospholipid membrane system. The different effects on the upper leaflet and lower leaflet of a lipid membrane due to melittin actions at different stages are obtained. The method developed in this work will be of great help in studying the dynamic processes of biological systems by using single-molecule tracking technology.
Research progress of puckered honeycomb monolayers
Authors: Meng Yu-Xin , Zhao Yi-Fan , Li Shao-Chun ,   National Laboratory of Solid State Microstructures, School of Physics, Nanjing University, Nanjing 210093, China,   Collaborative Innovation Center of Advanced Microstructures, Nanjing University, Nanjing 210093, China
Published: June 2021

Graphene, as the representative of two-dimensional materials, has varous novel physical properties and potential applications. The intrinsic zero band gap of graphene limits its application in semiconductor devices, and thus the search for new semiconducting alternative materials has become a current research hotspot. Phosphorene is the monolayer of black phosphorus and has a puckered honeycomb structure. Its advanced properties, such as adjustable direct band gap, high carrier mobility and in-plane anisotropy and so on, have recently aroused great research interest, thus opening up the research field of puckered honeycomb monolayers in group V elements. In this article, we first focus on the structure, synthesis and physical properties of five single-element two-dimensional materials (nitrogen, phosphorus, arsenic, antimony and bismuth) each with puckered honeycomb structure. Second, some binary two-dimensional materials with puckered honeycomb structure are discussed, including IV-VI and V-V compounds. These materials have their own unique crystal symmetry, and the properties can be controlled by changing their structures and dimensions. Finally, we also make a summary on some current challenges that need to be solved, and the possible future applications of these two-dimensional materials are also presented.
Irrigation Practices under Boro Rice Cultivation in Haor Areas of Sunamganj, Bangladesh
Authors: Chakraborty Debajani , Sarkar Pijush Kanti , Kashem Md. Abul
Published: June 2021

A field study was conducted in the ‘haor’ areas of Sunamgonj district, Bangladesh, aimed to investigate the present irrigation practices to identify the related problems for ‘Boro’ rice cultivation. The primary field data were collected by interviewing 120 farmers (landless, small, medium, and large farmers) through survey. Most of the farmers used ‘beel’ (37.5%) as the main source of irrigation water. As water-lifting devices, they mostly used Low Lift Pumps (77.5%). The cost of irrigation was observed the lowest at Derai [Tk. 12,232 ($ 146.784) per season] and the highest was at Dakshin Sunamganj [Tk. 46109 ($ 553.31) per season], respectively. The highest benefit-cost ratio (BCR) was observed at Derai (2.48) and the lowest was at Dowarabazar (2.01). The financial problem, less water supply, lack of irrigation equipment, and knowledge about operating the equipment were identified as the main problems suffered by the farmers. These problems can be solved by distributing irrigation equipments at a reasonable price, and arranging training programs to develop the farmers’ skills.
Customer Attitude towards the Purchase Behavior of Green Apparel Products Consumers; with Special Reference to the Sri Lankan Government University Students
Authors: Herath M. M. N. N. , Samarakoon S. M. A. K.
Published: June 2021

Aims: People are steadily more attentive to unsustainable consumption patterns due to severe environmental issues in the world. The study examines the factors that may affect the attitude towards green apparel products with particular reference to Sri Lankan university students’ families and analyze the attitude that affects green apparel products' purchasing behavior.

Methodology: Three hundred and eighty complete questionnaires were used to analyze the study. Descriptive statistics and simple and multiple regression analysis utilized for data analysis of the study. Three independent variables, namely environmental apparel knowledge, environmental consumer beliefs, and subjective norms, except the environmental apparel knowledge, shows a positive significant effect on green products' attitudes.

Results and Conclusions: Moreover, the study shows a positive impact on the attitude to purchase green apparel products. Producers should consider changes in the unsustainable consumption pattern of the young generation.
Effect of Fruit Harvest Time and Fermentation Methods on Seed Viability and Seedling Vigour in Oleaginous Citrullus lanatus
Authors: Yao Koffi Bertin , Beugré Manéhonon Martine , Adjoumani Koffi , Koffi N’Goran Delphine , Kouakou Tanoh Hilaire
Published: June 2021

Aims: In an attempt to improve the yields of Citrullus lanatus’s wlêwlê oilseed cultivar, generally low due to the lack of good germination seeds, the effect of fruit age at harvest and fermentation methods were studied. The present study is a contribution to the improvement the African oleaginous Cucurbits seed production system by optimizing the date of harvest combined to seed fermentation methods through enhancement of seed germination and seedling vigor.

Study Design: Seedling vigor was evaluated on farm trial using five completely randomized blocks represented by seedbeds constituting each, one replication.

Place and Duration of Study: The trials were carried out from July to December 2020, at the experimental farm of the Nangui Abrogoua University in the district of Abidjan, southern of Côte d'Ivoire between 5°17' and 5°31' North latitude and between 3°45' and 4°31' West longitude.

Methodology: Fruits from grown plants were harvested at five different times  20, 25, 30, 35 and 40 days after anthesis (DAA)] and seeds fermented following four methods  fermentation at ambient air (SFA); fermentation in a plastic bag exposed at ambient air (SFB); fermentation in plastic bag buried in 30 cm depth (SFD) and control or non-fermented (NF)]. Seeds from these 20 treatments (5 harvest time × 4 fermentation methods) were sown for viability tests in laboratory and seedling vigor in the field.

Results: Analysis of variance (ANOVA) showed that delaying harvest time (from 20 to 40 DAA) significantly (P < .001) improved fruit weight (from 512.20 to 760.50 g) and its seed content (from 71.75 to 230.70 seeds/fruit), seed size (length: 10.69 to 11.42 mm and width: 5.31 to 5.90 mm) and weight (5.16 to 6.37 g) as well as their viability (from 67.75 to 89.50 %). Moreover, in spite of facilitating seed extraction, all three fermentation methods (SFA, SFB and SFD) significantly improved seed viability and seedling vigor compared to control (NF) seeds. The highest agronomic performance (seed viability and produced seedling vigor), was obtained with fermentation under closed and deep confinement (SFD), followed by the closed confinement (SFB) and then by the open environment (SFA). Positive interaction (harvest time × fermentation method) revealed that the best performance was achieved with later harvested seeds (40 DAA) and closed fermented seeds (SFD) which could provide a better seed quality.

Conclusion: Agronomic performances (viability and vigor) are influenced by both harvest date and fermentation method. Late harvesting of the fruit (40 DAA) and fermentation in a very confined deep soil condition (SFD) ensures the production of high germination quality seeds.
Hepatoprotective Activity of Acampe praemorsa
Authors: Uppala Praveen Kumar , Rao G. S. N. Koteswara , Reddy A. Rajasekhar , Umasankar K. , Joshitha C. , Anusha Kanagala , Siddiqui Nadeem , Mallick Sarada Prasanna
Published: June 2021

Introduction: Liver is one of major functional organ in body, its damage can alter body metabolisms and other organs’ function. So, it is very important to maintain the healthy liver. Now a days, different chemicals and inadequate use of medicines are causing liver impairments including alcohol consumption. There is a need to identify safe hepatoprotective drugs against liver diseases from different natural resources including medicinal plants. Several medicinal plants have been using in traditional medicines against several diseases including liver disease and many of them are not scientifically proven. So, the current study was aimed to evaluate hepatoprotective nature of Acampe praemorsa.

Methodology: The hepatoprotective activity of A. praemorsa was carried on ethanol-induced liver toxicity on albino wistar rats by evaluating the levels of liver biomarker enzymes such as aspartate aminotransferase (AST), Alanine transaminase (ALT), Alkaline phosphatase (ALP), Total protein (T.ptn), and Total bilirubin (T.Bil).

Results: The extracts of Acampe praemorsa were found to be safe at different doses as there were no mortality and physio-psychological changes observed in toxicity study. The extracts of Acampe praemorsa has showed dose dependent hepatoprotective activity on controlling the altered liver biomarker enzymes when compared along with standard drug Liv 52. The hydroalcoholic extract showed better activity compared to ethyl acetate extracts. The percentage protection on liver biomarker enzymes levels of hydro-alcoholic extract at 100, 200, and 400 mg/kg on AST, ALT, ALP, T.ptn, and T.Bil was found to be 62.72%, 60.06%, 61.77%, 63.96% and 58.58% respectively.

Conclusion: The results of recent study support traditional medicinal use of Acampe praemorsa and provides the information about its’ hepatoprotective nature. The hepatoprotective activity of A. praemorsa was definitely due to presence of different phytochemical compounds in it as it was compared with Liv 52 which was also an herbal drug.
Application of cognitive stimulation in the care of institutionalized elderly people with dementia / Aplicação da estimulação cognitiva no cuidado ao idoso institucionalizado com demência
Authors: Nascimento Neyce de Matos Nascimento Matos , Souto Rafaella Queiroga , Araújo Gleicy Karine Nascimento de Araújo Nascimento , Santos Renata Clemente dos Santos Clemente
Published: June 2021

Objetivo: identificar as evidências científicas sobre os cuidados de enfermagem aos idosos institucionalizados com demência. Método: trata-se de uma revisão integrativa da literatura, com a utilização da estratégia PICo. Foram incluídos estudos publicados no intervalo de 2009 a 2018, nas bases de dados LILACS, CINAHL, a MEDLINE e a SCOPUS. Os artigos tiveram sua análise de qualidade realizada a partir do instrumento Mixed Methods Appraisal Tool. Resultado: de 6.144 textos inicialmente obtidos foram selecionados 7 artigos, sendo 54% publicados em 2010 e 14% no ano de 2016. As intervenções identificadas estão relacionadas à prática de atividades físicas e de estimulação cognitiva, as quais demonstram ser bastante positivas no cuidado ao idoso com demência, pois permite estimular funções cerebrais ainda preservadas, promovendo uma melhora na sua qualidade de vida. Conclusão: a maioria das intervenções identificadas podem ser aplicadas pela equipe multiprofissional e podem ser associadas, quando necessário, aos recursos farmacológicos.
Laser Direct Writing of Highly Crystalline Graphene on Polydimethylsiloxane for Fingertip‐Sized Piezoelectric Sensors
Authors: Hayashi Shuichiro , Morosawa Fumiya , Terakawa Mitsuhiro
Published: June 2021

The patterning of electrically conductive structures directly onto the polydimethylsiloxane (PDMS) surface is crucial for the realization of flexible and elastic devices. Herein, defocused femtosecond laser pulses are irradiated for the fabrication of highly crystalline graphitic carbon structures on PDMS and a high electrical conductivity of ≈51.6 S m−1 is achieved. Utilizing the elasticity of PDMS and the high conductivity of fabricated structures, a fingertip‐sized pressure sensor, which can detect pressures as low as ≈0.1 Pa, is realized. Moreover, a novel ring‐shaped heart rate (HR) monitor, capable of measuring the HR from the index finger, is demonstrated, indicating the potential of fabricated structures in miniature and wearable healthcare applications.
Corn response to incremental applications of sulfate‐sulfur
Authors: Goyal Diksha , Franzen David W. , Cihacek Larry Joseph , Chatterjee Amitava
Published: June 2021

Reports of sulfur (S) deficiency symptoms in corn (Zea mays L.) fields of the Red River Valley of North Dakota and Minnesota are increasing. Current soil tests cannot predict the availability of S correctly due to the presence of gypsum in soils of this region. Field trials were conducted to determine corn yield and S uptake response to incremental applications of S (0, 11, 22, 33, and 44 kg S ha–1) in the form of ammonium sulfate [(NH4)2SO4]. Corn yield and S uptake varied significantly between sites. Out of 12 sites, only two sites had the highest corn yield without S application. Corn grain S removal ranged between 11 and 17 kg S ha–1 at harvest. Fertilizer‐S (SO4) application did not result in a significant yield response. The current recommendation of 11 kg S ha–1 may be necessary to reduce the risk of future S deficiency across this region and compensate for the removal of S in grain due to the uncertainty of adequate plant available S.
Reducing Defects Density and Enhancing Hole Extraction for Efficient Perovskite Solar Cells Enabled by π‐Pb2+ Interactions
Authors: Wen Lirong , Rao Yi , Zhu Mingzhe , Li Ruitao , Zhan Jingbo , Zhang Linbao , Wang Li , Li Ming , Pang Shuping , Zhou Zhongmin
Published: June 2021

Molecular doping is an of significance approach to reduce defects density of perovskite and to improve interfacial charge extraction in perovskite solar cells. Here, we show a new strategy for chemical doping of perovskite via an organic small molecule, which features a fused tricyclic core, showing strong intermolecular π‐Pb2+ interactions with under‐coordinated Pb2+ in perovskite. This π‐Pb2+ interactions could reduce defects density of the perovskite and suppress the nonradiative recombination, which was also confirmed by the density functional theory calculations. In addition, this doping via π‐Pb2+ interactions could deepen the surface potential and downshift the work function of the doped perovskite film, facilitating the hole extraction to hole transport layer. As a result, the doped device showed high efficiency of 21.41 % with ignorable hysteresis. This strategy of fused tricyclic core‐based doping provides a new perspective for the design of new organic materials to improve the device performance.
Photoactivated In Situ Generation of Near Infrared Cyanines for Spatiotemporally Controlled Fluorescence Imaging in Living Cells
Authors: Song Gang , Heng Hao , Wang Jiaqi , Liu Ronghua , Huang Yiming , Lu Huan , Du Ke , Feng Fude , Wang Shu
Published: June 2021

Photoactivated trimerization of 2,3,3‐trimethyl‐3H‐indole derivatives created near infrared fluorophore Cy5. The synthetic method is air‐tolerant, photosensitizer free, metal free, and condensation agent free. Living cells make Cy5 on a time scale of minutes under white light irradiation at a low power intensity, with the monomer as the only exogenous agent. The new method is promising to find applications in cell studies for in situ spatiotemporally controlled fluorescence imaging in living cells.
Controlling the Covalent Reactivity of a Kinase Inhibitor with Light
Authors: Reynders Martin , Chaikuad Apirat , Berger Benedict‐Tilman , Bauer Katharina , Koch Pierre , Laufer Stefan , Knapp Stefan , Trauner Dirk
Published: June 2021

Covalent kinase inhibitors account for some of the most successful drugs that have recently entered the clinic and many others are in preclinical development. A common strategy is to target cysteines in the vicinity of the ATP binding site using an acrylamide electrophile. To increase the tissue selectivity of kinase inhibitors, it could be advantageous to control the reactivity of these electrophiles with light. Here, we introduce covalent inhibitors of the kinase JNK3 that function as photoswitchable affinity labels (PALs). Our lead compounds contain a diazocine photoswitch, are poor non‐covalent inhibitors in the dark, and become effective covalent inhibitors after irradiation with visible light. Our proposed mode of action is supported by X‐ray structures that explain why these compounds are unreactive in the dark and undergo proximity‐based covalent attachment following exposure to light.
A Synergistic Strategy of Manipulating the Number of Selenophene Units and Dissymmetric Central Core of Small Molecular Acceptors Enables Polymer Solar Cells with 17.5 % Efficiency
Authors: Yang Can , An Qiaoshi , Bai Hai‐Rui , Zhi Hong‐Fu , Ryu Hwa Sook , Mahmood Asif , Zhao Xin , Zhang Shaowen , Woo Han Young , Wang Jin‐Liang
Published: June 2021

A dissymmetric backbone and selenophene substitution on the central core was used for the synthesis of symmetric or dissymmetric A‐DA′D‐A type non‐fullerene small molecular acceptors (NF‐SMAs) with different numbers of selenophene. From S‐YSS‐Cl to A‐WSSe‐Cl and to S‐WSeSe‐Cl, a gradually red‐shifted absorption and a gradually larger electron mobility and crystallinity in neat thin film was observed. A‐WSSe‐Cl and S‐WSeSe‐Cl exhibit stronger and tighter intermolecular π–π stacking interactions, extra S⋅⋅⋅N non‐covalent intermolecular interactions from central benzothiadiazole, better ordered 3D interpenetrating charge‐transfer networks in comparison with thiophene‐based S‐YSS‐Cl. The dissymmetric A‐WSSe‐Cl‐based device has a PCE of 17.51 %, which is the highest value for selenophene‐based NF‐SMAs in binary polymer solar cells. The combination of dissymmetric core and precise replacement of selenophene on the central core is effective to improve Jsc and FF without sacrificing Voc.
Synthesis of Rhodium Complexes with Chiral Diene Ligands via Diastereoselective Coordination and Their Application in the Asymmetric Insertion of Diazo Compounds into E−H Bonds
Authors: Ankudinov Nikita M. , Chusov Denis A. , Nelyubina Yulia V. , Perekalin Dmitry S.
Published: June 2021

A new method for the synthesis of chiral diene rhodium catalysts is introduced. The readily available racemic tetrafluorobenzobarrelene complexes [(R2‐TFB)RhCl]2 were separated into two enantiomers via selective coordination of one of them with the auxiliary S‐salicyl‐oxazoline ligand. One of the resulting chiral complexes with an exceptionally bulky diene ligand [(R,R‐iPr2‐TFB)RhCl]2 was an efficient catalyst for the asymmetric insertion of diazoesters into B−H and Si−H bonds giving the functionalized organoboranes and silanes with high yields (79–97 %) and enantiomeric purity (87–98 % ee). The stereoselectivity of separation via auxiliary ligand and that of the catalytic reaction was predicted by DFT calculations.
Cycloaddition Cascades of Strained Alkynes and Oxadiazinones
Authors: Ramirez Melissa , Darzi Evan R. , Donaldson Joyann S. , Houk Kendall N. , Garg Neil K.
Published: June 2021

We report a computational and experimental study of the reaction of oxadiazinones and strained alkynes to give polycyclic aromatic hydrocarbons (PAHs). The reaction proceeds by way of a pericyclic reaction cascade and leads to the formation of four new carbon−carbon bonds. Using M06‐2X DFT calculations, we interrogate several mechanistic aspects of the reaction, such as why the use of non‐aromatic strained alkynes can be used to access unsymmetrical PAHs, whereas the use of arynes in the methodology leads to symmetrical PAHs. In addition, experimental studies enable the rapid synthesis of new PAHs, including tetracene and pentacene scaffolds. These studies not only provide fundamental insight regarding the aforementioned cycloaddition cascades and synthetic access to PAH scaffolds, but are also expected to enable the synthesis of new materials.
Spatial Order of Functional Modules Enabling Diverse Intracellular Performance of Fluorescent Probes
Authors: Duan Chong , Hu Jing‐Jing , Liu Rui , Dai Jun , Duan Mojie , Yuan Lizhen , Xia Fan , Lou Xiaoding
Published: June 2021

To overcome a series of challenges in tumor therapy, modular‐agent probes (MAPs) comprised of various functional modules have been proposed. Researchers have tried to optimize the MAPs by exploiting the new modules or increasing the numbers of module, while neglecting the configuration of various modules. Here, we focus on the different spatial arrangements of existing modules. By utilizing a tetraphenylethylene (TPE) derivative with stereochemical structure and dual modifiable end‐group sites as small molecule scaffold, two MAPs with same modular agents (module T for enhancing the internalization of MAPs by tumor cells and module M for causing mitochondrial dysfunction) but different spatial arrangements (on the one side, TM‐AIE, and two sides, T‐AIE‐M, of the molecule scaffold) are designed. T‐AIE‐M with larger RGD binding angle performed higher specificity, while TM‐AIE characterizing longer α‐helix structure displayed superior toxicity.
An Organic Host–Guest System Producing Room‐Temperature Phosphorescence at the Parts‐Per‐Billion Level
Authors: Chen Biao , Huang Wenhuan , Nie Xiancheng , Liao Fan , Miao Hui , Zhang Xuepeng , Zhang Guoqing
Published: June 2021

Manipulation of long‐lived triplet excitons in organic molecules is key to applications including next‐generation optoelectronics, background‐free bioimaging, information encryption, and photodynamic therapy. However, for organic room‐temperature phosphorescence (RTP), which stems from triplet excitons, it is still difficult to simultaneously achieve efficiency and lifetime enhancement on account of weak spin–orbit coupling and rapid nonradiative transitions, especially in the red and near‐infrared region. Herein, we report that a series of fluorescent naphthalimides—which did not originally show observable phosphorescence in solution, as aggregates, in polymer films, or in any other tested host material, including heavy‐atom matrices at cryogenic temperatures—can now efficiently produce ultralong RTP (ϕ=0.17, τ=243 ms) in phthalimide hosts. Notably, red RTP (λRTP=628 nm) is realized at a molar ratio of less than 10 parts per billion, demonstrating an unprecedentedly low guest‐to‐host ratio where efficient RTP can take place in molecular solids.
Two‐Dimensional Metal‐Organic Framework Film for Realizing Optoelectronic Synaptic Plasticity
Authors: Liu Youxing , Wei Yanan , Liu Minghui , Bai Yichao , Liu Guocai , Wang Xinyu , Shang Shengcong , Gao Wenqiang , Du Changsheng , Chen Jianyi , Liu Yunqi
Published: June 2021

2D metal‐organic framework (MOF) film as the active layer show promising application prospects in various fields including sensors, catalysis, and electronic devices. However, exploring the application of 2D MOF film in the field of artificial synapses has not been implemented yet. In this work, we fabricated a novel 2D MOF film (Cu‐THPP, THPP=5,10,15,20‐Tetrakis(4‐hydroxyphenyl)‐21H,23H‐porphine), and further used it as an active layer to explore the application in the simulation of human brain synapses. It shows excellent light‐stimulated synaptic plasticity properties, and exhibits the foundation function of synapses such as long‐term plasticity (LTP), short‐term plasticity (STP), and the conversion of STP to LTP. Most critically, the MOF based artificial synaptic device exhibits an excellent stability in atmosphere. This work opens the door for the application of 2D MOF film in the simulation of human brain synapses.
A Direct Organocatalytic Enantioselective Route to Functionalizedtrans‐Diels–Alder Products Having the Norcarane Scaffold
Authors: Barløse Casper L. , Østergaard Niklas L. , Bitsch René S. , Iversen Marc V. , Jørgensen Karl Anker
Published: June 2021

An enantioselective methodology to construct trans‐Diels–Alder scaffolds by organocatalysis with excellent selectivity, high yield and up to five contiguous stereocenters is presented. The reaction concept integrates the halogen effect and a novel discovered pseudo‐halogen effect to direct an endo‐selective, secondary‐amine catalyzed Diels–Alder reaction allowing for the subsequent formation of trans‐Diels–Alder cycloadducts featuring the norcarene scaffold. The methodology relies on the reaction between an in situ generated trienamine and an α‐brominated or α‐pseudo‐halogenated enone to form a fleeting cis‐Diels–Alder intermediate. The endo‐transition state‐enhanced by the (pseudo‐)halogen effect‐sets the stereochemistry that allows for a subsequent SN2‐like reaction at a tertiary center to obtain the trans‐Diels–Alder scaffold. The mechanism was investigated and supported by experimental results as well as computational studies.
A Molecular Hybrid of an Atomically Precise Silver Nanocluster and Polyoxometalates for H2 Cleavage into Protons and Electrons
Authors: Yonesato Kentaro , Yamazoe Seiji , Yokogawa Daisuke , Yamaguchi Kazuya , Suzuki Kosuke
Published: June 2021

Atomically precise silver (Ag) nanoclusters are promising materials as catalysts, photocatalysts, and sensors because of their unique structures and mixed‐valence states (Ag+/Ag0). However, their low stability hinders the in‐depth study of their intrinsic reactivity and catalytic property accompanying their redox processes. Herein, we demonstrate that a molecular hybrid of an atomically precise {Ag27}17+ nanocluster and polyoxometalates (POMs) can efficiently cleave H2 into protons and electrons. The Ag nanocluster accommodates electrons through the redox reaction from {Ag27}17+ to {Ag27}13+, and the POM ligands play the following important roles: (i) a significant stabilization of the typically unstable Ag nanocluster to preserve its structure during the redox reaction with H2, (ii) formation of a unique interface between the Ag nanocluster and metal oxides for efficient H2 cleavage, and (iii) storage of the generated protons on the negatively charged basic surface.