bluuebunny/crossref_metadata_2025 huggingface dataset:
IL-33 is produced by colon fibroblasts and differentially regulated in acute and chronic murine colitis
Authors: Waddell Amanda , Vallance Jefferson E. , Fox Sejal , Rosen Michael J.
Published: May 2021

IL-33 is upregulated in ulcerative colitis and has a protective role in chemically-induced acute murine colitis. We aimed to determine whether IL-33 influences Il10−/− chronic colitis and its cellular source in health and during colitis. Il10−/−Il33−/− and Il10−/−Il33+/+ littermates developed colitis of similar severity. Colon Il33 was induced in WT and Il10−/− mice exposed to DSS, but not in unchallenged Il10−/− mice with colitis. Il33-citrine reporter mice showed that Il33-citrine colocalized with α-smooth muscle actin+ myofibroblasts and vimentin+ fibroblasts in WT mice. Citrine+CD74+CD90hi inflammatory fibroblasts were increased with DSS treatment. IL-1β induced Il33 expression in colon myofibroblasts, but colon Il33 expression did not differ between DSS-treated WT and Il1r1−/− mice. In conclusion, deficiency of IL-33 does not alter the severity of chronic colitis in Il10−/− mice. Induction of Il33 upon DSS exposure in WT and Il10−/− mice, but not in unchallenged Il10−/− mice, suggests epithelial injury induces colon IL-33. Fibroblasts are the primary colonic source of IL-33 and IL-33-expressing CD90hiCD74+ fibroblasts are increased during DSS-induced colitis. IL-1β induces Il33 in colon myofibroblasts in vitro, but signaling through the IL-1R1 is not necessary for induction of IL-33 in DSS-induced colitis.
Prospective investigation of polyomavirus infection and the risk of adult glioma
Authors: Egan Kathleen M. , Kim Youngchul , Bender Noemi , Hodge James M. , Coghill Anna E. , Smith-Warner Stephanie A. , Rollison Dana E. , Teras Lauren R. , Grimsrud Tom K. , Waterboer Tim
Published: May 2021

Glioma is an aggressive primary tumor of the brain with a poorly understood etiology. We studied the association of 4 human polyomaviruses (HPyV)—JC virus (JCV), BK virus (BKV), human polyomavirus 6 (HPyV6), and Merkel cell polyomavirus (MCPyV) with glioma risk within the Cancer Prevention Study II in the US (CPS-II) and the Janus Serum Bank in Norway. Cohort participants subsequently diagnosed with glioma from the CPS-II (n = 37) and Janus Serum Bank (n = 323), a median of 6.9 and 15.4 years after blood collection, respectively, were matched to individual controls on age, sex, and date of blood draw. Serum antibodies to the major viral capsid protein (VP1) were used to establish infection history for each polyomavirus. Odds ratios (ORs) and 95% confidence intervals (CIs) were estimated using conditional logistic regression. In the Janus Serum Bank, MCPyV infection was associated with a higher risk of glioma overall (OR: 1.56; 95% CI 1.10, 2.19). A modest, nonsignificant positive association with MCPyV infection was also observed in CPS-II (OR: 1.29; 95% CI 0.54, 3.08). In both cohorts, glioma risk was not significantly related to infection with JCV, BKV or HPyV6. The present study suggests that MCPyV infection may increase glioma risk.
Efficient management strategy of COVID-19 patients based on cluster analysis and clinical decision tree classification
Authors: Li Zhi , Wang Ling , Huang Lv-shuai , Zhang Meng , Cai Xianhua , Xu Feng , Wu Fei , Li Honghua , Huang Wencai , Zhou Qunfang , Yao Jing , Liang Yong , Liu Guoliang
Published: May 2021

Early classification and risk assessment for COVID-19 patients are critical for improving their terminal prognosis, and preventing the patients deteriorate into severe or critical situation. We performed a retrospective study on 222 COVID-19 patients in Wuhan treated between January 23rd and February 28th, 2020. A decision tree algorithm has been established including multiple factor logistic for cluster analyses that were performed to assess the predictive value of presumptive clinical diagnosis and features including characteristic signs and symptoms of COVID-19 patients. Therapeutic efficacy was evaluated by adopting Kaplan–Meier survival curve analysis and cox risk regression. The 222 patients were then clustered into two groups: cluster I (common type) and cluster II (high-risk type). High-risk cases can be judged from their clinical characteristics, including: age > 50 years, chest CT images with multiple ground glass or wetting shadows, etc. Based on the classification analysis and risk factor analysis, a decision tree algorithm and management flow chart were established, which can help well recognize individuals who needs hospitalization and improve the clinical prognosis of the COVID-19 patients. Our risk factor analysis and management process suggestions are useful for improving the overall clinical prognosis and optimize the utilization of public health resources during treatment of COVID-19 patients.
Author Correction: Molecular and biophysical mechanisms behind the enhancement of lung surfactant function during controlled therapeutic hypothermia
Authors: Autilio C. , Echaide M. , Cruz A. , García-Mouton C. , Hidalgo A. , Da Silva E. , De Luca D. , Sørli Jorid B. , Pérez-Gil J.
Published: May 2021

An amendment to this paper has been published and can be accessed via a link at the top of the paper.
Comment on “Energy harvesting from shadow-effect” by Q. Zhang, Q. Liang, D. K. Nandakumar, S. K. Ravi, H. Qu, L. Suresh, X. Zhang, Y. Zhang, L. Yang, A. T. S. Wee and S. C. Tan, Energy Environ. Sci., 2020, 13, 2404
Authors: Das Amit K. , Sahu V. K. , Ajimsha R. S. , Misra P.
Published: May 2021

A physical mechanism of “energy harvesting from shadow-effect” considering the equivalent circuit of the device to consist of two Schottky junctions.
Integration of sequential analytical processes into sub-100 nm channels: volumetric sampling, chromatographic separation, and label-free molecule detection
Authors: Tsuyama Yoshiyuki , Morikawa Kyojiro , Mawatari Kazuma
Published: May 2021

Separation analysis was demonstrated in sub-100 nm scale nanofluidic channels by the integration of sequential analytical processes including absorption-based label-free molecule detection.
UV-visible light-induced photochemical synthesis of benzimidazoles by coomassie brilliant blue coated on W–ZnO@NH2nanoparticles
Authors: Chen Ruijuan , Jalili Zahra , Tayebee Reza
Published: May 2021

A new photochemical route is disclosed in the preparation of a wide range of benzimidazoles in air under the illumination of an HP mercury lamp in the absence of any oxidizing species catalyzed by heterogenized W–ZnO@NH2–CBB.
Synthesis of asymmetrical diaminobis(alkoxo)-bisphenol compounds and their C1-symmetrical mono-ligated titanium(iv) complexes as highly stable highly active antitumor compounds
Authors: Nahari Gilad , Tshuva Edit Y.
Published: May 2021

Substituting differently the two aromatic rings of bis(phenolato)-bis(alkoxo) ligands yields C1-symmetrical titanium(iv) complexes that are highly soluble and stable in biological media and display marked cytotoxicity toward various cancer cells.
Biomimetic camouflage delivery strategies for cancer therapy
Authors: Asrorov Akmal M. , Gu Zeyun , Li Feng , Liu Lingyun , Huang Yongzhuo
Published: May 2021

Biomimetic camouflage strategies can modulate the bio-fate of therapeutics and target cancer cells. Various endogenous components have been used to develop biomimetic drug delivery systems and can serve as either carriers or coating materials.
Enhanced CO2methanation at mild temperature on Ni/zeolite from kaolin: effect of metal–support interface
Authors: Sholeha Novia Amalia , Mohamad Surahim , Bahruji Hasliza , Prasetyoko Didik , Widiastuti Nurul , Abdul Fatah Nor Aiza , Jalil Aishah Abdul , Taufiq-Yap Yun Hin
Published: May 2021

Different Na-zeolites as supports of Ni metal were successfully synthesized from kaolin-based material. Combination of interfacial interaction Ni-support and surface basicity promoted CO2methanation reaction at a low temperature of ∼200 °C.
Insight of UV-vis spectra and atmospheric implication for the reaction of ˙OH radical towards glyphosate herbicide and its hydrates
Authors: Holtomo Olivier , Mbigah Manain Derrick , Nsangou Mama , Motapon Ousmanou
Published: May 2021

The rate constant of the reactions of ˙OH radical with glyphosate (GPS) and its hydrates (GPS(H2O)n=1–3) were evaluated using the dual method M06-2X/6-311++G(df,p)//6-31+G(df,p) over the temperature range of 200–400 K.
Improvement in optical properties of Cs4PbBr6 nanocrystals using aprotic polar purification solvent
Authors: Shi Zikuan , Yang Yu , Sun Xin-Yuan , Lang Feng , Lin Liangwu
Published: May 2021

We demonstrate the influence mechanism on the optical properties of Cs4PbBr6 during purification of solutions with different protonated levels and polarities.
Recent progress of MOF-derived porous carbon materials for microwave absorption
Authors: Ma Mingliang , Bi Yuxin , Tong Zhouyu , Liu Yanyan , Lyu Ping , Wang Rongzhen , Ma Yong , Wu Guanglei , Liao Zijian , Chen Yan
Published: May 2021

MOF-derived PC materials with unique characteristic have been widely concerned as microwave absorbers over the years.
A high-efficiency oxygen evolution electrode material of a carbon material containing a NiCo bimetal
Authors: Guan Hongxin , Wang Na , Feng Xuanxuan , Bian Shaokang , Li Wei , Chen Yan
Published: May 2021

The preparation of highly efficient, stable, and low-cost electrocatalysts for the oxygen evolution reaction (OER) and the hydrogen evolution reaction (HER) is still a challenge for the development of new energy systems.
Molybdenum-modified mesoporous SiO2 as an efficient Lewis acid catalyst for the acetylation of alcohols
Authors: Hlatshwayo Xolani S. , Ndolomingo Matumuene Joe , Bingwa Ndzondelelo , Meijboom Reinout
Published: May 2021

A suitable, expeditious and well-organized approach for the acetylation of alcohols with acetic anhydride in the presence of 5%MoO3–SiO2 as an optimum environmentally benign heterogeneous catalyst was developed.
Zr- and Ce-doped Li6Y(BO3)3 electrolyte for all-solid-state lithium-ion battery
Authors: Okumura Toyoki , Shiba Yoshitaka , Sakamoto Noriko , Kobayashi Takeshi , Hashimoto Saori , Doguchi Kentaro , Ogaki Harunobu , Takeuchi Tomonari , Kobayashi Hironori
Published: May 2021

Ionic conductivity of Li6Y(BO3)3 (LYBO) is enhanced by the substitution of tetravalent ions through an increase in the conduction pathways etc. Zr,Ce-doped LYBO can be used as an electrolyte for all-solid-state batteries via a cosintering process.
Visual Attention to Cued Targets in Simulated Aided Augmentative and Alternative Communication Displays for Individuals With Intellectual and Developmental Disabilities
Authors: Wilkinson Krista M. , O'Neill Zimmerman Tara , Light Janice
Published: May 2021

Purpose

Many aided augmentative and alternative communication (AAC) systems require the use of an external display that is represented via a visual modality. It is critical to evaluate and understand visual–perceptual processing in individuals with disabilities who could benefit from AAC. One way to evaluate how individuals process visual materials is through research-based automated eye-tracking technologies that obtain a fine-grained stream of data concerning gaze paths of visual attention.

Method

The current study examined how individuals with autism spectrum disorder (
n
= 13), Down syndrome (
n
= 13), intellectual and developmental disabilities (
n
= 9), or typical development (
n
= 20) responded to a spoken prompt to find a thumbnail-sized navigation key within a complex AAC display, including a main visual scene display (VSD) and a navigation bar of four thumbnail-sized VSDs. Stimuli were presented on a monitor containing automated eye-tracking research technology that recorded patterns of visual attention.

Results

Participants across groups spent more time fixating on a target thumbnail VSD navigation image after the presentation of the spoken cue to look at the target, compared to before the presentation of the spoken cue; they also spent more time looking at the target thumbnail VSD than the other thumbnail-sized VSDs in the navigation bar after the cue.

Discussion

Participants were able to locate the target thumbnail VSDs, even within the context of a visually complex AAC display. Implications for the design of AAC displays and for assessment of comprehension are discussed.
On/off switching of adhesion in gecko‐inspired adhesives
Authors: Yamaguchi Tetsuo , Akamine Akira , Sawae Yoshinori
Published: May 2021

In this study, the adhesion‐detachment behaviour of a gecko‐inspired adhesive pad was investigated to understand the on/off switching mechanisms of adhesion in gecko feet. A macroscopic spatula model was fabricated using silicone rubber, and adhesion tests combining lateral sliding and vertical debonding were conducted. It was observed that the contact state and the adhesion force of the pad vary considerably with the direction of lateral sliding prior to debonding, and that the pad achieves adhesion during debonding even when it loses contact due to excess lateral sliding. These results explain the mechanisms behind the on/off switching and stable adhesion of gecko feet, and suggest the possibility of developing new‐generation adhesives capable of switchable adhesion.
Experimental demonstration of single‐pixel imaging using a multi‐core fibre
Authors: Ikeda Kanami , Kameyama Yohei , Koyama Osanori , Yamada Makoto
Published: May 2021

This letter reports a proof‐of‐concept experiment conducted on a novel application of the multi‐core fibre (MCF), where image reconstruction is based on a single‐pixel imaging (SPI) technique and the diffraction pattern emitted from an MCF. The technique is intended to reduce the size of the SPI system, the applications of which can now be extended with the help of this study.
Dynamic characteristics after bias stress of GaN HEMTs with field plate on free‐standing GaN substrate
Authors: Ma Qiang , Ando Yuji , Wakejima Akio
Published: May 2021

This paper investigates the electron trapping behaviour after bias stress in GaN high‐electron‐mobility transistors (HEMTs) fabricated on GaN substrate. On‐resistance (RON) and electron‐trap‐induced threshold voltage shift (ΔVth) of GaN HEMTs on GaN substrate are determined by gate quiescent bias (Vgq) and independent of drain quiescent bias (Vdq). This result indicates that the current collapse of GaN HEMTs is mainly attributed to the electron injection in barrier layer under gate region. Moreover, time constants of electron emission are dependent on the Vgq. At least two time constants (τ1 and τ2) are found to exist in the HEMTs after being switched from an off‐state (Vgq ≤ −30 V, Vdq = 0 V) to an open channel condition. The τ1 and τ2 continue to increase with increasing |Vgq|. It is speculated that the presence of multi‐trap energy states in barrier layer results in the quiescent bias‐dependence of time constants.
Non‐linear optical limiting technology based on backward stimulated Brillouin scattering in grade‐index optical fibres
Authors: Xu Yixiang , Huang Jian , Wu Zhengnan , Lu Yuangang
Published: May 2021

An effective non‐linear optical limiting technology is proposed here based on backward stimulated Brillouin scattering in grade‐index optical fibres. The excellent non‐linear optical limiting performance is experimentally verified by using 0.5 and 1 m grade‐index quartz fibres at the wavelength of 1064 nm. The linear transmittance for 0.5 and 1 m fibres are both beyond 96% and the lowest non‐linear transmittance are 6.1% and 1.5%, respectively. This is the best non‐linear optical limiting performance that can be achieved at present.
Dynamic deployment of multi‐UAV base stations with deep reinforcement learning
Authors: Wu Guanhan , Jia Weimin , Zhao Jianwei
Published: May 2021

Unmanned aerial vehicles (UAVs) can be utilized as aerial base stations (BSs) to provide auxiliary communication services. In this letter, we propose a deep reinforcement learning (DRL)‐based dynamic deployment method for multi‐UAV communications. The phasic policy gradient (PPG) is designed to improve the sample efficiency and the attention of the multi‐UAV deployment. Simulation results are provided to verify the effectiveness of the proposed method.
Toward quantification of flexibility for an electricity‐heat integrated energy system: Secure operation region approach
Authors: Su Jia , Chiang Hsiao Dong , Zeng Yuan
Published: May 2021

With the tight interconnection of multiple energy flows in the integrated energy system, the security problem owing to the interaction between the electric network and the heating network has gained wide attention. To facilitate the security assessment of the integrated energy system, this article initially proposes the definition for the secure operation region (SOR) of the heat‐electricity integrated energy system under the exact AC power flow model and non‐linear heating formulation. The SOR of the integrated energy system is defined as a set of operation points for which the operational constraints of the electric network and the coupling heating network are satisfied. Next, complete characterization for the SOR of the integrated energy system is achieved based on the non‐linear dynamical quotient gradient system. After that, the evaluation criteria based on the integrated energy system (IES) SOR is defined to screen flexibility providers. Flexibility improvement by utilizing plug‐in hybrid electrical vehicle, installing energy storage, installing a heat storage tank, installing electric boiler, and utilizing building thermal inertia in the heat network is simulated and measured by application of the completely characterized IES SOR. Finally, numerical studies are given to verify the effectiveness of the proposed scheme.
UGV‐UAV robust cooperative positioning algorithm with object detection
Authors: Wang Dongjia , Lian Baowang , Tang Chengkai
Published: May 2021

Traditional Global Navigation Satellite Systems (GNSS) experience their limitations in urban canyons. However, it is significant to improve the accuracy of positioning with the rapid development of smart cities. To solve this problem, a UGV‐UAV robust cooperative positioning algorithm with object detection is proposed, which utilises an unmanned aerial vehicle (UAV) to assist an unmanned ground vehicle (UGV) to achieve accurate positioning. When the UAV is in the sky with a good reception of satellite signals, the UGV uses the YOLOv3 object detection method to detect the UAV in images captured by camera, and acquires visual measurements including angles and ranges of the ground camera relative to the UAV through the proposed monocular vision measuring with object detection (ODMVM) model. Then, in order to solve the problem that visual measurement is disturbed by the real world, a robust Kalman filter is introduced that integrates measurements from available GNSS, inertial measurement unit (IMU), monocular camera, and the position broadcast of cooperative UAV to obtain more robust and accurate position estimation. Experimental and simulation results show that the proposed cooperation positioning algorithm can improve the positioning accuracy by 73.63% compared with the traditional cooperation positioning algorithm in urban canyons.
Winding open‐circuit fault‐tolerant operation of single DC‐link dual‐inverter fed three‐phase open‐end induction motor drive
Authors: Chakrabarti Abanishwar , Saha Ardhendu , Biswas Sujit K.
Published: May 2021

This study presents a winding open‐circuit fault‐tolerant control scheme for an open‐end induction motor drive with common DC bus for dual inverters. The proposed control scheme also permits balanced three‐phase operation of the same motor under healthy operation. It can suppress common mode current easily, yet permits maximum DC bus utilisation in both operating modes. It is mathematically established here that during fault‐tolerant operation, the magnetising current increases by a factor of √3. As a result, the airgap flux during fault‐tolerant operation is same as that during balanced three‐phase operation. An analytical relation is proposed for maximum torque capability of the machine during fault‐tolerant operation, taking into account the limit of winding current to its rated value and increase of magnetising current during such an operation. Extensive mathematical analysis is supported by simulation and experimental results to validate the performance of the proposed scheme during balanced three‐phase operation as well as winding open‐circuit fault‐tolerant operation.
A robust passivity based control strategy for quasi‐resonant converters
Authors: Ayubirad Mostafa Ali , Siavoshani Simin Amiri , Yazdanpanah Mohammad Javad
Published: May 2021

This paper presents a robust passivity‐based control (RPBC) strategy for half‐wave zero‐voltage switching quasi‐resonant (HW‐ZVS‐QR) buck and boost type converters. The proposed controller is based on energy shaping and damping injection. Theoretical analysis shows that the resulted closed‐loop HW‐ZVS‐QRs are globally asymptotically stabilised even if the physical constraint on the magnitude of the control signal is taken into account. Also, an integral function of the output error is added into the feedback path of the conventional passivity‐based control design. As a result, such controller not only offers a global asymptotic stable operation but also provides strong robustness to a wide range of parameter mismatch. It is also demonstrated that the proposed controller stabilises the converter in cases where the widely used linear multiloop controller fails. Finally, some simulation and experimental results comparing the performance of the proposed RPBC with that of the conventional linear multiloop controller are presented.
Tertiary regulation of cascaded run‐of‐the‐river hydropower in the islanded renewable power system considering multi‐timescale dynamics
Authors: Qiu Yiwei , Lin Jin , Liu Feng , Dai Ningyi , Song Yonghua , Chen Gang , Ding Lijie
Published: May 2021

To enable power supply in rural areas and to exploit clean energy, fully renewable power systems consisting of cascaded run‐of‐the‐river hydropower and volatile energies such as photovoltaic (pv) and wind are built around the world. In islanded operation, the primary and secondary frequency controls, that are hydro governors and automatic generation control (AGC), are responsible for the frequency stability. However, due to limited water storage capacity of run‐of‐the‐river hydropower and river dynamics constraints, without coordination between the cascaded plants, the traditional AGC cannot fully exploit the adjustability of hydropower. When imbalances between the volatile energy and load occur, load shedding can be inevitable. To address this issue, this paper proposes a coordinated tertiary control approach by jointly considering power system dynamics and the river dynamics that couples the cascaded hydropower plants. To unify the multi‐timescale dynamics of the power system and river dynamics to establish a controller that coordinates the cascaded plants, the relation between AGC parameters and turbine discharge is approximated by a polynomial surrogate model. The cascaded plants are coordinated by optimising AGC participation factors in a receding‐horizon manner. Simulation of a real‐life system shows the proposed method significantly reduces load loss under pv volatility.
An integrated approach on proton exchange membrane fuel cell performance enhancement combining flower pollination algorithm and nanofluids
Authors: Kumar Priya , Gnanasekar Subashini , Andrews Nirmala Grace , Natarajan Rajasekar
Published: May 2021

Proton exchange membrane fuel cell (PEMFC) is widely popular for its inherent advantages like low operating temperature, high efficiency, durability, and reliability. However, modelling its characteristics is often restricted by virtue of its shortage of data and strongly coupled multivariate behaviour. At the same time, when operated within its temperature limits, PEMFC systems exhibit maximum efficiency; otherwise, they cause membrane dryness, poor ionic conductivity and less efficiency. Therefore, PEMFC modelling alongside thermal management is of interest in recent years. With the benefits rendered by the metaheuristics algorithm, an integrated approach is emphasised in this work for achieving twin objectives of modelling PEMFC together with thermal management. An aspiration to enhance PEMFC performance via mathematical modelling, flower pollination algorithm for parameter identification as well as thermal conductivity property computation is outlined. Simulated values are experimentally matched using copper‐based nanofluids. The selection of copper (Cu) is justified by its thermal conductivity property and cost. For brevity, synthesis procedure, characterisation and estimation of thermal conductivity property is expounded in methodology. Numerous experimentations on various vol% fractions combinations lying between 0.05% and 0.5% indicate that Cu nanoparticle when dispersed in base fluids such as water and ethylene glycol (EG) substantially improves thermal conductivity property. Especially, among different combinations, nanofluid with EG and water mixture achieves the highest thermal conductivity value of 1.4255.
Frequency security constrained control of power electronic‐based generation systems
Authors: Steinkohl Joachim , Peyghami Saeed , Wang Xiongfei , Davari Pooya , Blaabjerg Frede
Published: May 2021

Power grids with high integration of power electronic converters face new issues that have not existed before. The frequency in the power system is highly related to the inertia and the rotational speed of the operational synchronous machines. This is now changing, as the converter‐based generation units are contributing increasingly to the balancing of active power in the modern power grid. Several frequency control designs for the power electronic‐based generation units have been presented in the past. However, optimal control structures and settings are dependent on the current power grid parameters and operation. The converter‐based units allow the transmission system operators to change their behaviour according to their grid requirements much more dynamical than ever before. The paper proposes a new analysis framework that can be utilized to find the best‐suited control settings in converter‐based units to enhance the system frequency reliability. The proposed framework is demonstrated in a study case by varying the settings of one frequency control scheme currently used in wind power plants in the Danish grid codes and validated on the IEEE 24‐Bus reliability test system with additional wind power integration.
Grid integration aspects of wave energy—Overview and perspectives
Authors: Said Hafiz Ahsan , Ringwood John V.
Published: May 2021

The sustained development of wave energy in the past two decades makes it one of the most promising renewable energy resources to be added to the diverse mixture of supply systems. The inherent difficulty of grid integration of wave energy involves various aspects such as suitable control of power converters and power conditioning processes, allowing for the extraction of the best quality power. This paper presents a comprehensive review of different aspects of grid integration of wave energy devices, including classification of wave energy devices based on their impacts on grid integration, grid requirements imposed by the grid codes and storage technologies used for the grid integration of wave energy converters (WECs). This study also analyses various grid integration studies on wave energy converters, with particular emphasis on power converter technology and control. Furthermore, specific attention is given to the combinational studies that use wave energy combined with other renewable resources due to their positive synergies in lowering the costs of energy produced and that hold an opportunity for future research. An economic case is presented for wave energy devices based on value on the grid.
A novel bilayer coordinated control scheme for global autonomous economic operation of islanded hybrid AC/DC microgrids
Authors: Zheng Shunwei , Liao Kai , Yang Jianwei , He Zhengyou , Sun Xiaofei
Published: May 2021

This paper proposes a novel distributed bilayer coordinated control scheme (BCCS) to realize the autonomous economic operation of islanded hybrid AC/DC microgrids, which only requires a sparse communication link. In the lower layer, the optimal power reference iterative algorithm (OPRIA)‐based droop control is proposed to realize the economic dispatch of each subgrid individually, while the frequency of AC subgrid and the bus voltage of DC subgrid are regulated to their rated values. Then, the upper‐layer control for the interlinking converter is designed to achieve the global economic operation of the hybrid AC/DC microgrid through optimizing the exchanging power between AC and DC subgrids. The proposed BCCS has the advantage of reaching the economic operation and frequency/voltage regulation simultaneously for the hybrid AC/DC microgrid. Besides, the proposed BCCS realizes the stable and economic operation with less communication, flexible controllability, and good compatibility of renewable energy sources. Numerical simulation results based on Matlab/Simulink verify the effectiveness and excellent performance of the proposed BCCS even with the integration of renewable energy sources, and the test based on RT‐LAB illustrates the good real‐time performance of the proposed control scheme.
Multi-dimensional population modelling using frbpoppy: Magnetars can produce the observed fast radio burst sky
Authors: Gardenier D. W. , van Leeuwen J.
Published: May 2021

Fast radio bursts (FRBs) are energetic, short, bright transients that occur frequently over the entire radio sky. The observational challenges following from their fleeting, generally one-off nature have prevented the identification of the underlying sources producing the bursts. As the population of detected FRBs grows, the observed distributions of brightness, pulse width, and dispersion measure now begin to take shape. Meaningful direct interpretation of these distributions is, however, made impossible by the selection effects that telescope and search pipelines invariably imprint on each FRB survey. Here, we show that multi-dimensional FRB population synthesis can find a single, self-consistent population of FRB sources that can reproduce the real-life results of the major ongoing FRB surveys. This means that individual observed distributions can now be combined to derive the properties of the intrinsic FRB source population. The characteristics of our best-fit model for one-off FRBs agree with a population of magnetars. We extrapolated this model and predicted the number of FRBs future surveys will find. For surveys that have commenced, the method we present here can already determine the composition of the FRB source class, and potentially even its subpopulations.
Wide companions to M and L subdwarfs withGaiaand the Virtual Observatory
Authors: González-Payo J. , Cortés-Contreras M. , Lodieu N. , Solano E. , Zhang Z. H. , Gálvez-Ortiz M.-C.
Published: May 2021

Aims.The aim of the project is to identify wide common proper motion companions to a sample of spectroscopically confirmed M and L metal-poor dwarfs (also known as subdwarfs) to investigate the impact of metallicity on the binary fraction of low-mass metal-poor binaries and to improve the determination of their metallicity from the higher-mass binary.

Methods.We made use of Virtual Observatory tools and large-scale public surveys to look inGaiafor common proper motion companions to a well-defined sample of ultracool subdwarfs with spectral types later than M5 and metallicities below or equal to −0.5 dex. We collected low-resolution optical spectroscopy for our best system, which is a binary composed of one sdM1.5 subdwarf and one sdM5.5 subdwarf located at ∼1360 au, and for another two likely systems separated by more than 115 000 au.

Results.We confirm one wide companion to an M subdwarf, and infer a multiplicity for M subdwarfs (sdMs) of 1.0−1.0+2.0% for projected physical separations of up to 743 000 au. We also find four M–L systems, three of which are new detections. No colder companion was identified in any of the 219 M and L subdwarfs of the sample, mainly because of limitations on the detection of faint sources withGaia. We infer a frequency of wide systems for sdM5–9.5 of 0.60−0.60+1.17% for projected physical separations larger than 1 360 au (up to 142 400 au). This study shows a multiplicity rate of 1.0−1.0+2.0% in sdMs, and 1.9−1.9+3.7% in extreme M subdwarfs. We did not find any companion for the ultra M subdwarfs of our sample, establishing an upper limit of 5.3% on binarity for these objects.
Study of frost resistance and drought resistance of apple tree varieties of VNIISPK breeding on clonal rootstock 54–118
Authors: Galasheva Anna , Krasova Nina
Published: May 2021

Apple tree varieties on clonal rootstock 54–118 were studied in terms of frost resistance and drought resistance. The purpose of the research is to study the resistance to frost and drought of apple tree varieties of VNIISPK breeding on clonal rootstock 54–118. Climatic conditions affect fruit trees and further lead to a sharp decrease in the fruit productivity and commercial qualities. The problem study of resistance to various extreme growing conditions (including frost, low temperatures, drought and high temperatures) is relevant. A variety that has a high resistance under various adverse weather conditions is considered as winter-hardy, i.e. shows all the components of frost resistance. The study of the main components of winter hardiness (I, III, IV) showed that apple tree varieties (Orlik, Venyaminovskoye, Sinap Orlovsky, Veteran, Svezhest, Rozhdestvenskoye, Bolotovskoye - of the FSBSI VNIISPK breeding; Antonovka obyknovennaya - of local selection on clonal rootstock 54–118) had minor bud damage. The bark and wood were not damaged. When studying the total water content of leaf tissues during the growing season, all varieties on the clonal rootstock 54–118 were assigned to the average level of hydration. In laboratory conditions, over the years of research, the varieties had a high indicator of the ability to restore water content of leaf tissues after drought. On the clonal rootstock 54–118 the apple tree varieties are able to withstand thaws, spring frosts, droughts and dry winds.
The diversity of blackberry habitus and its significance for cultivars’ growing in the conditions of central Russia
Authors: Gruner Lidia , Kornilov Boris
Published: May 2021

The article deals with the main morphological groups of blackberries — erect, trailing and intermediates — semi-erect and semi-trailing. The nature of shoots’ growth and the way of natural vegetative reproduction were used as the basic criteria for this grouping, which together reflect the polymorphism of the plant being one of the adaptability indicators to different growth conditions. The expediency of such division for grouping of the existing blackberry cultivars’ diversity with complex genetic origin was substantiated. As an additional criterion of this grouping, the shoots growth dynamics of morphological groups’ typical representatives has been studied, which shows their differences during vegetation and in transition to period of plants’ rest. In the phase of growth completion, the differences between group representatives were particularly clear: erect are characterized by early completion of growth processes, trailing do not finish them until the end of the growing season, semi-trailing/semi-erect complete growth in the term in between the first two groups. There is a difference in winter resistance of old erect cultivars and more modern members of this group of blackberries with different genetic origin; the latter’s significant advantages are noted due to their thornlessness and lack of abundant growth. The role of plants’ habitus of the main morphological groups’ representatives for their cultivation in the conditions of the middle zone of Russia and, first of all, for overwintering cultivars; the value of both erect primocane-fruit cultivars and trailing - less winter-resistant, but the most convenient for winter shelter by habitus.
Formation and evaluation of the genefund of subtropical cultures in the Nikita Botanical Gardens
Authors: Khokhlov Sergey , Tsiupka Sergei , Panyushkina Evgeniya , Kharchenko Anton , Melnikov Vladimir
Published: May 2021

The article presents the stages of formation and the results of the study of the genefund of persimmon, ziziphus, olives and figs in the Nikita Botanical Gardens. Based on the results of many years research, the best cultivars have been selected that are donors of economically valuable characteristics. Among the cultivars of foreign selection, the following cultivars are selected according to the best complex of economically valuable characteristics: persimmons (Fuyu, Kiara, Hiakume, Hachia, Rojo Brillante, Sharon, Batumsky II, etc.), ziziphus (Zhu-Tau-Zao, Chinese 2A, Chinese 93, Ta-Yan-Zao, Ya-Zao), olives (Ascolano, Tiflis, Coreggiolo, Della Madonna, Otur, etc.), figs (Randino, Grosse Violette de Bordeaux, Castle Kennedy etc.). As a result of directed interspecific and intraspecific hybridization of the best foreign cultivars, a significant hybrid fund was formed and new cultivars were bred, which surpass foreign cultivars in a number of characteristics. Among them are persimmon cultivars: Stella, Zolotistaya, Zvezdochka, Mechta, Nikitskaya Bordovaya, Yuzhnaya Krasavitsa, Ukrainka, Suvenir Oseni, Rossiyanka, etc., cultivars of ziziphus Koktebel, Meteor, Tavrika, Yalita, Sinit, Radoslav, Konfetny, etc., cultivars of olives: Manita, Skorospelaya, Violetta, Nikitskaya, Krymskaya Prevoskhodnaya, etc., fig cultivars: Yantarny, Sukhofruktovy Nikitsky, Podarok Oktyabru, Sabrucia Rozovaya, etc.
The source material estimation of early-maturing group soybeans by adaptability parameters
Authors: Galichenko Anna , Fokina Evgeniya
Published: May 2021

The article presents the results of 2018—2020 study of 22 early-maturing group soybeans samples of the collection nursery; those samples are of various ecological-geographical origin according to adaptability parameters, plasticity and stability in the conditions of the south of the Amur region, the analysis of yield variability was carried out. The research was carried out on the experimental field of the laboratory of selection and genetics of soybeans FSBSI FSC All-Russian Scientific and Recearch Center of soybean, Sadovoye village, Tambov region. The average varietal soybean seeds yield in the years of research amounted to 2.37 t/ha. Based on the results of agro-ecological assessment of 22 soybean samples, adaptive, plastic and stable samples have been identified, which have an insignificant variation indicator in yield: Heihe 25 (V=3.23%; Ка=1.14; bi=1.00; Si2=0.03), Hei 06–1625 (V=4.69%; Ка=1.06; bi=1.29; Si2=0.01), Hei 05–1031 (V=3.74%; Ка=1.03; bi=1.60; Si2=0.01) and McCall (V=2.34%; Ка=1.06; bi=1.03; Si2=0.01). These genotypes are of practical interest as initial parent forms in selection for adaptability in conditions of the Amur region.
Creation of new initial forms of black currant (Ribes nigrum L.) in breeding for adaptation
Authors: Sazonov Fedor , Kulikov Ivan , Tumaeva Tatyana , Sazonova Irina
Published: May 2021

The article presents the results of studying the black currant varieties collection of the Kokinsky control station of the FSBSI FRC for Horticulture (Bryansk region) for winter hardiness, resistance to Sphaerotheca, and currant gall mite in order to create new initial forms based on the selected genotypes, characterized by a high level of adaptation for their inclusion in the breeding work to improve the crop assortment. The best combinations of crosses (Gamayun × Nara, 33-27-1 × Kipiana, 33-27-1 × Bryanskiy Agat, Favorit × Dar Smolyaninovoy, etc.), the initial forms for inbreeding and free pollination, in the progeny of which the largest number of winter-hardy seedlings, characterized by resistance to Sphaerotheca and gall mite, were identified. Promising winter-hardy Sphaerotheca-resistant forms were identified 4-63-4, 72-03-7, 3-37-26/02, 62-03-7, 1-5-1, 63-35-1, 3-134-01, 28-03-1, 5-82-02, 1-91-01, immune to gall mite.
Comprehensive assessment of red currant varieties in Altai
Authors: Nazaryuk Nadezhda , Sorokopudov Vladimir , Sorokopudova Olga , Nigmatzyanov Radmil
Published: May 2021

Red currant (Ribes rubrum L.) is a berry crop promising for cultivation in Siberia. The purpose of the work was to study the elements of productivity and biochemical composition of fruits in 17 varieties of R. rubrum of various origins of the VNIISPK breeding. This article presents the results of the study of red currant varieties selected by VNIISPK in the Altai. Most varieties are highly resistant to gall aphids, with the exception of ‘Valentinovka’, ‘Orlovskaya Zvezda’ and ‘Orlovchanka’ - in some years, their damage was noted to a very weak degree. As sources of valuable biochemistry, the following varieties were identified: with a high content of soluble dry substances - Asya, Bayana, Vika, Dar Orla, Marmeladnitsa, Osipovskaya; sugar - Asya, Bayana, Roza; vitamin C - Asora, Asya, Protein, Vika, Marmeladnitsa, sugar-acid index - Asora, Orlovchanka, Roza. The varieties Asora, Asya, Bayana, Valentinovka, Vika, Dana, Dar Orla, Marmeladnitsa, Orlovskaya Zvezda, Orlovchanka, Osipovskaya, and Roza were identified according to the complex of economically useful traits (yield, large-fruited, biochemical composition, resistance to harmful organisms), which can be recommended for cultivation in the conditions of the Altai Ob region.
Use of SSR markers to study genetic polymorphism in members of the Ribes L. genus from the VNIISPK collection
Authors: Pavlenko Anna , Dolzhikova Maria , Pikunova Anna , Bakhotskaya Annastasiya
Published: May 2021

This study was the first time in Russia to carry out a large-scale (127 samples) assessment of the diverse gene pool of black currant and red currant, the study of intervarietal polymorphism between varieties of the Ribes L. genus from the VNIISPK collection. A cluster analysis of the genetic similarity of black currant varieties (53 varieties), red currant (73 varieties) and one gooseberry variety was performed using 14 SSR markers. Based on the data obtained, a dendrogram was built, in which a number of clusters with high bootstrap support (BS, %) were distinguished. At BS>50%, the coefficients of pairwise genetic similarity between varieties varied from 0.4 to 0.91. The studied representatives of the Ribes genus merged into two main clusters of red currant and black currant. The blackcurrant cluster was joined by gooseberries. The SSR analysis method allows to reveal broad perspectives in the field of identifying varieties affiliation to species.
Effect of prohexadione calcium on vegetative growth, yield and scab development on ‘Sinap Orlovskii’ apple trees
Authors: Kashirskaya Natalia , Kuzin Andrei , Kochkina Anna
Published: May 2021

There are many apple orchards in the Russian Federation where trees were trained with volumetric canopies; the vigor of these canopies must be suppressed. Prohexadione calcium (calcium 3-hydroxy-5-oxo-4-propionyl-cyclohex-3-enecarboxylate) was developed to inhibit the gibberellins biosynthesis to reduce vegetative growth. The study was done in the commercial orchard of “Planeta sadov” LLC in Michurinck district of Tambov Region (53°02’11.9 “N 40°29’29.9 “E). This research was aimed to evaluate the influence of prohexadione calcium on the length of one-year shoot growth, yield, and scab development on trees of vigorous apple cultivar ‘Sinap Orlovskii,’ planted 6 x 4 m (418 tr. ha-1). After 1.25 + 1.25 g ha-1 prohexadione calcium double treatment, the length of one-year shoots was 1.96 (2019) and 1.60 (2020) times less than Control 1 (without prohexadione calcium application and hand pruning) and 2,00 times less than in hand pruning treatment. The application of prohexadione calcium inhibited apple tree height and reduced the average height growth rate by 10.7% (2019) and 17.0% (2020). Growth retardant treatments stimulated significant yield increases and improved the commercial value of fruits. The enhance of scab protection improved under the influence of prohexadione calcium treatments. The application of growth retardant increased the alternate bearing index.
Study of frost resistance of generative buds of scion/ rootstock combinations of sweet cherry by freezing in controlled conditions
Authors: Upadysheva G.Yu. , Motyleva S.M. , Tumaeva T.A. , Mertvischeva M.E. , Upadyshev M.T.
Published: May 2021

The paper presents the results of two-year research on frost resistance study in 18 scion/rootstock combinations of sweet cherry: Fatezh and Chermashnaya varieties grafted on 9 rootstocks (Izmailovsky, AVCH-2, V-5-88, VC-13, Moskoviya, VSL-2, Stepnoy Rodnik, Colt and seedling rootstock Prunus magaleb L.). The research was carried out in 2019-2020 in the laboratory of physiology and biochemistry of FSBSI «Federal Horticultural Research Center for Breeding, Agrotechnology and Nursery» by artificial freezing method in the climate chamber TH-6 JEIO TECH -1000. It was established that after freezing at t = - 29ºC, the floral rudiments' preservation in the Fatezh variety was more than 80%, and in the Chermashnaya variety — about 40%. Limits of frost resistance change of varieties' reproductive buds depending on the rootstock were shown: Fatezh variety — from 62.2% (VSL-2) to 81.7% (Izmailovsky), and Chermashnaya variety — from 25.5% (P. magaleb L) to 65% (Izmailovsky). When using Izmailovsky and AVCH-2 clone rootstock, the preservation of flower rudiments increased by 15 -20% compared to P. magaleb L. The most frost-resistant scion/rootstock combinations were revealed: Fatezh/Izmailovsky and Fatezh/AVCH-2, which preserved more than 87% of live rudiments. A positive correlation between floral buds' frost resistance and chlorogenic acid content has been established.
Accumulation of alkaloids in plants of the family Boraginaceae depending on environmental conditions places of growth
Authors: Akhkubekova Amina A. , Tamakhina Aida Ya.
Published: May 2021

Due to the lack of information on the influence of environmental factors on the accumulation of pyrrolizidine alkaloids and their content in certain species of this family Boraginaceae, the aim of the study was to assess the level of alkaloids accumulation in the aboveground and under-ground parts of Symphytum asperum Lepech., S. caucasicum M. Bieb., Echium vulgare L., and Pulmonaria mollis Wulfen ex Hornem. depending on climatic, orographic and edaphic conditions. The localization of alka-loids in rhizomes with roots, glandular trichomes of leaves and stems, epidermal cells was revealed. The content of alkaloids in the aboveground phytomass decreases in the series S. asperum ˃ S. caucasicum ˃ Е. vulgare, and in the underground S. caucasicum ˃ S. asperum ˃ Е. vulgare ˃ P. mollis. At the end of the growing season, an increase in the accumulation of alkaloids in the underground phytomass and a decrease in the aboveground one were noted. An increase in air temperature and a decrease in precipitation contribute to an increase in the accumulation of alkaloids in roots and shoots. The level of correlation between the accumulation of alkaloids and the content of trace elements varies from high (Cu, Zn, Mo) to medium (Mn, Pb). The results obtained indicate the need to take into account environmental factors in the implementation of medicinal collections and the preparation of feed from plants.