bluuebunny/crossref_metadata_2025 huggingface dataset:
Identification of aroma compounds in a commonly prescribed oral nutritional supplement and associated changes in olfactory abilities with human ageing
Authors: Lester Sophie , Cornacchia Leonardo , Corbier Camille , Taylor Moira A. , Ayed Charfedinne , Yang Ni , Lim Mui , Linforth Rob , Fisk Ian
Published: August 2021

Undernutrition is prevalent in the older adult population. Oral nutritional supplements (ONS) are a clinically effective nutritional intervention, however, patient acceptance of ONS can be limited by their palatability. While sensory attributes such as sweetness and mouthfeel have been investigated, the contribution made by aroma to the perceived flavour of ONS has not been studied. Firstly, this research aimed to identify the aroma active compounds within a commonly prescribed ONS using estimated odour activity values (OAV) and gas chromatography olfactometry mass spectrometry (GC-O-MS). Secondly, age related differences in olfactory detection were explored. Eight aroma active compounds were identified within the ONS, including diacetyl (sweet), isoamyl acetate (banana), dimethyl trisulfide (sulfur) and methanethiol (sulfur). When compared with younger adults (n = 24, 18–44 years), older adults (n = 24, 62–80 years) had higher detection thresholds for all aroma compounds and this was significant for isoamyl acetate (sweet, fruity) and methanethiol (sulfur) (p = 0.01 and p = 0.03, respectively). Thus, a decline in olfactory sensitivity was present in the older subjects included in the study, and this reduced detection sensitivity was aroma specific. Thus, older adults’ flavour perception of ONS likely depends on the combined effect of product factors (the aroma profile) along with age related consumer factors (the degree of impairment in perception). This is a fundamental study which will aid future research into how the aroma profile, and associated age related impairments in perception, shape the global perception of ONS for nutritionally at risk older individuals.
The determinants of lipid profiles in early adolescence in a Ugandan birth cohort
Authors: Koopman Jan Pieter R. , Lule Swaib A. , Zziwa Christopher , Akurut Hellen , Lubyayi Lawrence , Nampijja Margaret , Akello Florence , Balungi Priscilla , Tumusiime Josephine , Oduru Gloria , Elliott Alison M. , Webb Emily L. , Bradley John
Published: August 2021

Dyslipidaemia in adolescence tracks into adulthood and is an important risk factor for cardiovascular disease. Little is known about the effects of environmental exposures and early-life exposure to infectious diseases common to tropical regions on lipids. In 1119 early adolescent participants in the Entebbe Mother and Baby Study, we used linear regression to examine whether prenatal, childhood or adolescent factors are associated with lipid levels. Reduced high-density lipoprotein (HDL) and elevated triglyceride levels were common (prevalence 31% and 14%, respectively), but elevated low-density lipoprotein (LDL) or total cholesterol (TC) were rare. Current malaria infection was associated with lower mean LDL (adjusted ß − 0.51; 95% CI − 0.81, − 0.21), HDL (adjusted ß − 0.40; 95% CI − 0.56, − 0.23), and TC levels (adjusted ß − 0.62; 95% CI − 0.97, − 0.27), but higher mean triglyceride levels (geometric mean ratio (GMR) 1.47; 95% CI 1.18–1.84). Early-life asymptomatic malaria was associated with modest reductions in HDL and TC. Body mass index (BMI) was positively associated with LDL, TC, and triglycerides. No associations with helminth infection were found. Our findings suggest that early-life factors have only marginal effects on the lipid profile. Current malaria infection and BMI are strongly associated with lipids and important to consider when trying to improve the lipid profile.
A numerical frame work of magnetically driven Powell-Eyring nanofluid using single phase model
Authors: Jamshed Wasim , Eid Mohamed R. , Nisar Kottakkaran Sooppy , Nasir Nor Ain Azeany Mohd , Edacherian Abhilash , Saleel C. Ahamed , Vijayakumar V.
Published: August 2021

The current investigation aims to examine heat transfer as well as entropy generation analysis of Powell-Eyring nanofluid moving over a linearly expandable non-uniform medium. The nanofluid is investigated in terms of heat transport properties subjected to a convectively heated slippery surface. The effect of a magnetic field, porous medium, radiative flux, nanoparticle shapes, viscous dissipative flow, heat source, and Joule heating are also included in this analysis. The modeled equations regarding flow phenomenon are presented in the form of partial-differential equations (PDEs). Keller-box technique is utilized to detect the numerical solutions of modeled equations transformed into ordinary-differential equations (ODEs) via suitable similarity conversions. Two different nanofluids, Copper-methanol (Cu-MeOH) as well as Graphene oxide-methanol (GO-MeOH) have been taken for our study. Substantial results in terms of sundry variables against heat, frictional force, Nusselt number, and entropy production are elaborate graphically. This work’s noteworthy conclusion is that the thermal conductivity in Powell-Eyring phenomena steadily increases in contrast to classical liquid. The system’s entropy escalates in the case of volume fraction of nanoparticles, material parameters, and thermal radiation. The shape factor is more significant and it has a very clear effect on entropy rate in the case of GO-MeOH nanofluid than Cu-MeOH nanofluid.
A highly-sensitive genetically encoded temperature indicator exploiting a temperature-responsive elastin-like polypeptide
Authors: Vu Cong Quang , Fukushima Shun-ichi , Wazawa Tetsuichi , Nagai Takeharu
Published: August 2021

Genetically encoded temperature indicators (GETIs) allow for real-time measurement of subcellular temperature dynamics in live cells. However, GETIs have suffered from poor temperature sensitivity, which may not be sufficient to resolve small heat production from a biological process. Here, we develop a highly-sensitive GETI, denoted as ELP-TEMP, comprised of a temperature-responsive elastin-like polypeptide (ELP) fused with a cyan fluorescent protein (FP), mTurquoise2 (mT), and a yellow FP, mVenus (mV), as the donor and acceptor, respectively, of Förster resonance energy transfer (FRET). At elevated temperatures, the ELP moiety in ELP-TEMP undergoes a phase transition leading to an increase in the FRET efficiency. In HeLa cells, ELP-TEMP responded to the temperature from 33 to 40 °C with a maximum temperature sensitivity of 45.1 ± 8.1%/°C, which was the highest ever temperature sensitivity among hitherto-developed fluorescent nanothermometers. Although ELP-TEMP showed sensitivity not only to temperature but also to macromolecular crowding and self-concentration, we were able to correct the output of ELP-TEMP to achieve accurate temperature measurements at a subcellular resolution. We successfully applied ELP-TEMP to accurately measure temperature changes in cells induced by a local heat spot, even if the temperature difference was as small as < 1 °C, and to visualize heat production from stimulated Ca2+ influx in live HeLa cells induced by a chemical stimulation. Furthermore, we investigated temperatures in the nucleus and cytoplasm of live HeLa cells and found that their temperatures were almost the same within the temperature resolution of our measurement. Our study would contribute to better understanding of cellular temperature dynamics, and ELP-TEMP would be a useful GETI for the investigation of cell thermobiology.
Mitochondrial dysfunction associated with autophagy and mitophagy in cerebrospinal fluid cells of patients with delayed cerebral ischemia following subarachnoid hemorrhage
Authors: Youn Dong Hyuk , Kim Youngmi , Kim Bong Jun , Jeong Myeong Seon , Lee Jooeun , Rhim Jong Kook , Kim Heung Cheol , Jeon Jin Pyeong
Published: August 2021

Decreased mitochondrial membrane potential in cerebrospinal fluid (CSF) was observed in patients with subarachnoid hemorrhage (SAH) accompanied by delayed cerebral ischemia (DCI). However, whether abnormal mechanisms of mitochondria are associated with the development of DCI has not been reported yet. Under cerebral ischemia, mitochondria can transfer into the extracellular space. Mitochondrial dysfunction can aggravate neurologic complications. The objective of this study was to evaluate whether mitochondrial dysfunction might be associated with autophagy and mitophagy in CSF cells to provide possible insight into DCI pathogenesis. CSF samples were collected from 56 SAH patients (DCI, n = 21; and non-DCI, n = 35). We analyzed CSF cells using autophagy and mitophagy markers (DAPK1, BNIP3L, BAX, PINK1, ULK1, and NDP52) via qRT-PCR and western blotting of proteins (BECN1, LC3, and p62). Confocal microscopy and immunogold staining were performed to demonstrate the differentially expression of markers within dysfunctional mitochondria. Significant induction of autophagic flux with accumulation of autophagic vacuoles, increased expression of BECN1, LC3-II, and p62 degradation were observed during DCI. Compared to non-DCI patients, DCI patients showed significantly increased mRNA expression levels (2−ΔCt) of DAPK1, BNIP3L, and PINK1, but not BAX, ULK1, or NDP52. Multivariable logistic regression analysis revealed that Hunt and Hess grade ≥ IV (p = 0.023), DAPK1 (p = 0.003), and BNIP3L (p = 0.039) were related to DCI. Increased mitochondrial dysfunction associated with autophagy and mitophagy could play an important role in DCI pathogenesis.
Food intake precipitates seizures in temporal lobe epilepsy
Authors: Tényi Dalma , Janszky József , Jeges Sára , Schulze-Bonhage Andreas
Published: August 2021

Various factors have been considered as potential seizure precipitants. We here assessed the temporal association of food intake and seizure occurrence, and characteristics of seizures and epilepsy syndromes involved. 596 seizures from 100 consecutive patients undergoing long-term video-EEG monitoring were analyzed. Preictal periods of 60 min were assessed as to the occurrence of food intake, and latencies between food intake and seizure onset were analyzed. Seizures of temporal origin were highly significantly more frequently preceded by food intake compared to those of extratemporal origin; and were associated with shorter food intake-seizure latency. Seizure precipitation by food intake showed male predominance. Shorter food intake-seizure latency was associated with less severe seizures and less frequent contralateral spread of epileptic discharges. We here show for the first time that not only in specific rare reflex epilepsies but in the most frequent form of focal epilepsy, temporal lobe epilepsy, seizures are significantly precipitated by food intake. Seizure occurrence was increased over a period of up to one hour following food intake, and remained more localized in terms of both ictal EEG spread and as reflected by seizure severity. This finding supports the emerging concepts of ictogenesis, implying a continuum between reflex and spontaneous seizures—instead a dichotomy between them.
Depression symptoms as longitudinal predictors of the psychological impact of COVID-19 pandemic in hypertensive patients
Authors: D’Addario Marco , Zanatta Francesco , Adorni Roberta , Greco Andrea , Fattirolli Francesco , Franzelli Cristina , Giannattasio Cristina , Steca Patrizia
Published: August 2021

COVID-19 has brought considerable changes and caused critical psychological responses, especially among frail populations. So far, researchers have explored the predictive effect of diverse factors on pandemic-related psychological distress, but none have focused on the impact of prior depression and anxiety symptomatology adopting an extended (10-year) longitudinal design. 105 patients aged over 60, affected by hypertension who participated in a previous longitudinal study were assessed through a follow-up telephone structured interview. The Hospital Anxiety and Depression Scale (HADS) and the Impact of Event Scale-Revised (IES-R) were used for assessing depression and anxiety symptoms and the psychological impact of COVID-19, respectively. Multiple linear regression analyses were conducted. At the assessment, participants did not report clinically relevant depression, anxiety, and psychological pandemic-related distress symptoms. However, significant mean differences between baseline and current follow-up evaluations for both depression and anxiety were found, reflecting a decrease in symptomatology over time (p < .001). Baseline depression symptoms (β = 1.483, p = .005) significantly predicted the psychological impact of COVID-19 after 10 years. Conversely, their decrease (β = −1.640, p < .001) and living with others (β = −7.274, p = .041) significantly contributed to lower psychological distress scores. Our findings provide insight into the predisposing influence of depressive symptoms on pandemic-related psychological distress ten years later. Preventive interventions and strategies considering these factors are needed to better pre-empt the severe mental consequences of the pandemic.
Implementation of a multisite, interdisciplinary remote patient monitoring program for ambulatory management of patients with COVID-19
Authors: Coffey Jordan D. , Christopherson Laura A. , Glasgow Amy E. , Pearson Kristina K. , Brown Julie K. , Gathje Shelby R. , Sangaralingham Lindsey R. , Carmona Porquera Eva M. , Virk Abinash , Orenstein Robert , Speicher Leigh L. , Bierle Dennis M. , Ganesh Ravindra , Cox Debra L. , Blegen R. Nicole , Haddad Tufia C.
Published: August 2021

Established technology, operational infrastructure, and nursing resources were leveraged to develop a remote patient monitoring (RPM) program for ambulatory management of patients with COVID-19. The program included two care-delivery models with different monitoring capabilities supporting variable levels of patient risk for severe illness. The primary objective of this study was to determine the feasibility and safety of a multisite RPM program for management of acute COVID-19 illness. We report an evaluation of 7074 patients served by the program across 41 US states. Among all patients, the RPM technology engagement rate was 78.9%. Rates of emergency department visit and hospitalization within 30 days of enrollment were 11.4% and 9.4%, respectively, and the 30-day mortality rate was 0.4%. A multisite RPM program for management of acute COVID-19 illness is feasible, safe, and associated with a low mortality rate. Further research and expansion of RPM programs for ambulatory management of other acute illnesses are warranted.
In situ imaging reveals disparity between prostaglandin localization and abundance of prostaglandin synthases
Authors: Duncan Kyle D. , Sun Xiaofei , Baker Erin S. , Dey Sudhansu K. , Lanekoff Ingela
Published: August 2021

Prostaglandins are important lipids involved in mediating many physiological processes, such as allergic responses, inflammation, and pregnancy. However, technical limitations of in-situ prostaglandin detection in tissue have led researchers to infer prostaglandin tissue distributions from localization of regulatory synthases, such as COX1 and COX2. Herein, we apply a novel mass spectrometry imaging method for direct in situ tissue localization of prostaglandins, and combine it with techniques for protein expression and RNA localization. We report that prostaglandin D2, its precursors, and downstream synthases co-localize with the highest expression of COX1, and not COX2. Further, we study tissue with a conditional deletion of transformation-related protein 53 where pregnancy success is low and confirm that PG levels are altered, although localization is conserved. Our studies reveal that the abundance of COX and prostaglandin D2 synthases in cellular regions does not mirror the regional abundance of prostaglandins. Thus, we deduce that prostaglandins tissue localization and abundance may not be inferred by COX or prostaglandin synthases in uterine tissue, and must be resolved by an in situ prostaglandin imaging.
Emerging beyond-graphene elemental 2D materials for energy and catalysis applications
Authors: Fan Feng Ru , Wang Ruoxing , Zhang Hua , Wu Wenzhuo
Published: August 2021

This review summarizes the recent progress of elemental two-dimensional (2D) materials beyond graphene with unique structures and properties, focusing on their applications in energy and catalysis.
Covalent organic framework-LZU1@PEI@Fe3O4-based magnetic dispersive micro-solid phase extraction of tetracyclines from environmental water prior to HPLC analysis
Authors: Zhang Ying , Ning Yuhan , Liao Wanliang , Wang Weiping , Wang Ai-Jun
Published: August 2021

Schematic of the m-μ-dSPE-HPLC strategy for the extraction and detection of TCs.
Electrocatalytic reduction of CO2 to CO and HCO2− with Zn(ii) complexes displaying cooperative ligand reduction
Authors: Berro Patrick , Norouziyanlakvan Somayeh , Rao Gyaneshwar Kumar , Gabidullin Bulat , Richeson Darrin
Published: August 2021

Air-stable zinc(ii) complexes, [Zn(κ2-2,6-{Ph2PNMe}2(NC5H3))Br2] (1) and [Zn(κ2-2-{Ph2PNMe}(NC5H3))Br2] (2) are reported and 1 was capable of electrocatalytic reduction of CO2 at −2.3 V vs. Fc+/0 to give CO/HCO2H in mixed H2O/acetonitrile solutions.
Effect of Hf doping on He behavior in tritium storage material ZrCo
Authors: Kong Xianggang , Yu You , Shen Yanhong , Song Jiangfeng
Published: August 2021

The addition of the Hf atom favors He accumulation in the surrounding of Hf, improving the ability of helium retention.
Photocatalytic redox on the surface of colloidal silver nanoparticles revealed by second harmonic generation and two-photon luminescence
Authors: Xue Shan , Chen Shun-Li , Ling Qing , Yuan Qunhui , Gan Wei
Published: August 2021

Second harmonic generation and two-photon luminescence measurements revealed the photocatalytic redox on the surface of colloidal silver nanoparticles under femtosecond laser irradiation.
Atomic structure of light-induced efficiency-degrading defects in boron-doped Czochralski silicon solar cells
Authors: Meyer Abigail R. , Taylor P. Craig , Venuti Michael B. , Eley Serena , LaSalvia Vincenzo , Nemeth William , Page Matthew R. , Young David L. , Stradins Paul , Agarwal Sumit
Published: August 2021

Using electron paramagnetic resonance, we show that under light exposure, nearly all the 1016 boron doping sites in Si degrade to form shallow traps. Of these 1016 traps, only 1012–1013 cm−3 are spin-active and responsible for light-induced degradation.
Ameliorated membranous nephropathy activities of two ethanol extracts from corn silk and identification of flavonoid active compounds by LC-MS2
Authors: Wang Xizhu , Yuan Liyan , Dong Yifei , Bao Zhijie , Ma Tiecheng , Lin Songyi
Published: August 2021

We speculate that the ameliorated MN activity of corn silk relates mainly to PR-CSEE and the synergistic action of the 12 flavonoid components therein, and that apigenin and its derivatives may play a major role.
Direct para-C–H heteroarylation of anilines with quinoxalinones by metal-free cross-dehydrogenative coupling under an aerobic atmosphere
Authors: Xu Jun , Huang Lin , He Lei , Liang Chenfeng , Ouyang Yani , Shen Jiabin , Jiang Min , Li Wanmei
Published: August 2021

This study demonstrates a metal-free cross-dehydrogenative coupling for direct para-C–H heteroarylation of anilines with quinoxalinones using air as the sole oxidant and H2O/DMSO as the solvent.
Characteristic activity of phosphorous acid in the dehydration condensation of a chitin-derived nitrogen-containing sugar alcohol
Authors: Yang Cheng , Sagawa Takuya , Fukuoka Atsushi , Kobayashi Hirokazu
Published: August 2021

H3PO3 converts a chitin-derived sugar alcohol to a potential monomer for polymer production by a mechanism different from that for strong acid catalysts.
Boronic-acid-derived covalent organic frameworks: from synthesis to applications
Authors: Frey Laura , Jarju Jenni J. , Salonen Laura M. , Medina Dana D.
Published: August 2021

Modular, well-defined, and robust hierarchical functional materials are targets of numerous synthesis endeavors.
Sustainable composites from biodegradable poly(butylene succinate) modified with thermoplastic starch and poly(butylene adipate-co-terephthalate): preparation and performance
Authors: Wei X. Y. , Ren L. , Sun Y. N. , Zhang X. Y. , Guan X. F. , Zhang M. Y. , Zhang H. X.
Published: August 2021

A ternary blend of biodegradable polymers, namely PBS-g-GMA, thermoplastic starch (TPS) and poly(butylene adipate-co-terephthalate) (PBAT), was successfully fabricated attempt to achieve novel biodegradable composites with comprehensive properties.
Controlled density glycodendron microarrays for studying carbohydrate–lectin interactions
Authors: Di Maio Antonio , Cioce Anna , Achilli Silvia , Thépaut Michel , Vivès Corinne , Fieschi Franck , Rojo Javier , Reichardt Niels-C.
Published: August 2021

Density depended binding and selectivity is studied on glycodendron microarray with defined valency, which were prepared by on-chip synthesis and analysed by in situ MALDI-TOF MS.
Protecting carbohydrates with ethers, acetals and orthoesters under basic conditions
Authors: Liang Yang , Pedersen Christian M.
Published: August 2021

Chlorinated ethyl and vinyl ethers are introduced at various positions of carbohydrates and gives access to acetals and ortho-esters under basic conditions.
Sequence-defined oligomer as a modular platform for selective sub-picomolar detection and removal of Hg2+
Authors: Jose Anna , Nanjan Pandurangan , Porel Mintu
Published: August 2021

A modular synthetic platform for selective sensing and removal of Hg2+ was developed.
Thermoresponsive polymers as macromolecular coordination ligands: complexation-dependence of thermally induced aggregation in aqueous solution
Authors: Meier Maximilian Felix Toni , Thetiot Franck , Pittala Narsimhulu , Lieberwirth Ingo , Kunzler Cleiton , Triki Smail , Jonas Ulrich
Published: August 2021

Novel dual-responsive macromolecular ligands for metal coordination were developed, for which the aggregation state is affected by the two stimuli of temperature and Fe2+ions.
Porous polyimide framework based on perylene and triazine for reversible potassium-ion storage
Authors: Wu Jialing , Di Sijia , Huang Wei , Wu Yunling , Huang Qiliang , Zhao Xuan , Yu Xiaohan , Zhang Mochun , Ye Hualin , Li Yanguang
Published: August 2021

A porous polyimide framework was prepared via condensation between perylenetetracarboxylic dianhydride and triazine and investigated as an electrode material for reversible K+-ion storage. It exhibited a large reversible capacity, good rate performance, and long cycling stability up to 1000 cycles at 5 A g−1.
Improved positive polaron stability of the p-type host for long lifetime in phosphorescent organic light-emitting diodes
Authors: Kang Ji Ae , Lim Junseop , Lee Jun Yeob
Published: August 2021

The device lifetime of phosphorescent organic light-emitting diodes was improved by employing a hole-transport-type host derived from carbazole with phenyl blocking groups at the 3- or 6-positions.
High-throughput immunosensor chip coupled with a fluorescent DNA dendrimer for ultrasensitive detection of cardiac troponin T
Authors: Wang Ruike , Zong Chen , Li Gairu , Wang Junhong , Kong Tiantian , Li Fei , Chang Junmin
Published: August 2021

A novel fluorescence imaging platform based on a high-throughput immunosensor chip and a DNA dendrimer capped with plenty of fluorescent dyes was proposed for ultrasensitive quantitation of cardiac troponin T.
Coumarin–carbazole based functionalized pyrazolines: synthesis, characterization, anticancer investigation and molecular docking
Authors: Patel Mrugesh , Pandey Nilesh , Timaniya Jignesh , Parikh Paranjay , Chauhan Alex , Jain Neeraj , Patel Kaushal
Published: August 2021

Coumarin–carbazole based functionalised pyrazolines: synthesis, anticancer activity and molecular docking.
Soft synthesis and characterization of goethite-based nanocomposites as promising cyclooctene oxidation catalysts
Authors: Kuncser Andrei Cristian , Vlaicu Ioana Dorina , Pavel Octavian Dumitru , Zavoianu Rodica , Badea Mihaela , Radu Dana , Culita Daniela Cristina , Rostas Arpad Mihai , Olar Rodica
Published: August 2021

Goethite based nanocomposites with different compositions (6FeO(OH)·MnO(OH)·0.5H2O, xFeO(OH)·M(OH)2·yH2O or xFeO(OH)·MO·yH2O where M = Co, Ni, Cu or Zn) have been prepared by a soft chemical synthesis via acetate hydrolysis.
Urea-doped carbon dots as fluorescent switches for the selective detection of iodide ions and their mechanistic study
Authors: Wang Kai , Geng Cuihuan , Wang Fang , Zhao Yajun , Ru Zongling
Published: August 2021

Urea-doped carbon dots (N-CDs) have been successfully fabricated for monitoring iodide ions; the reduced lifetime of N-CDs demonstrated that the excited energy dissipation led to a dynamic fluorescence quenching process.
Mixed-halide triphenyl methyl radicals for site-selective functionalization and polymerization
Authors: Chen Lisa , Arnold Mona , Blinder Rémi , Jelezko Fedor , Kuehne Alexander J. C.
Published: August 2021

Specifically addressable mixed-halide TTMs with improved stability and reactivity are presented to enable complex open-shell small molecules and polymers.
Correction: Functionalized pyridine in pyclen-based iron(iii) complexes: evaluation of fundamental properties
Authors: Mekhail Magy A. , Pota Kristof , Schwartz Timothy M. , Green Kayla N.
Published: August 2021

Correction for ‘Functionalized pyridine in pyclen-based iron(iii) complexes: evaluation of fundamental properties’ by Magy A. Mekhail et al., RSC Adv., 2020, 10, 31165–31170. DOI: 10.1039/d0ra05756h.
Introducing deep eutectic solvents in enolate chemistry: synthesis of 1-arylpropan-2-ones under aerobic conditions
Authors: Vitale Paola , Cicco Luciana , Perna Filippo Maria , Capriati Vito
Published: August 2021

An environmentally friendly procedure for the generation of enolates from 1-arylpropan-2-ones, followed by functionalization with electrophiles and (hetero)aryl halides in deep eutectic solvents under aerobic conditions, is disclosed.
Synthesis of structurally-defined polymeric glycosylated phosphoprenols as potential lipopolysaccharide biosynthetic probes
Authors: Wang Lei , Lowary Todd L.
Published: August 2021

The synthesis of lipid-linked polysaccharides containing 11 and 27 monosaccharides via a ‘frame-shift’ strategy is described. The work provides biosynthetic probes and highlights challenges in synthesizing structurally-defined polymeric glycans.
The power of trichlorosilylation: isolable trisilylated allyl anions, allyl radicals, and allenyl anions
Authors: Georg Isabelle , Bursch Markus , Endeward Burkhard , Bolte Michael , Lerner Hans-Wolfram , Grimme Stefan , Wagner Matthias
Published: August 2021

Treatment of hexachloropropene (Cl2CC(Cl)–CCl3) with Si2Cl6 and [nBu4N]Cl (1 : 4 : 1) in CH2Cl2 results in a quantitative conversion to the trisilylated, dichlorinated allyl anion salt [nBu4N][Cl2CC(SiCl3)–C(SiCl3)2] ([nBu4N][1]).
The effect of dimensionality on the charge carrier mobility of halide perovskites
Authors: Tailor Naveen Kumar , Yukta  , Ranjan Rahul , Ranjan Sudhir , Sharma Tejasvini , Singh Anand , Garg Ashish , Nalwa Kanwar Singh , Gupta Raju Kumar , Satapathi Soumitra
Published: August 2021

The impact of electronic dimensionality of the perovskite lattice on the charge carrier transport and device efficiency and stability.
Facile one-step synthesis and enhanced photocatalytic activity of a WC/ferroelectric nanocomposite
Authors: Zhang Man , Wang Yaqiong , Liu Jianguo , Thangamuthu Madasamy , Yue Yajun , Yan Zhongna , Feng Jingyu , Zhang Dou , Zhang Hongtao , Guan Shaoliang , Titirici Maria-Magdalena , Abrahams Isaac , Tang Junwang , Zhang Zhen , Dunn Steve , Yan Haixue
Published: August 2021

A WC/RbBi2Ti2NbO10 nanocomposite exhibits excellent photocatalytic behaviour, which is attributed to its ferroelectric nature and the loaded WC as a cocatalyst.
A new strontium based reactive carbonate composite for thermochemical energy storage
Authors: Vieira Adriana P. , Williamson Kyran , Humphries Terry D. , Paskevicius Mark , Buckley Craig E.
Published: August 2021

A new reactive carbonate composite based on SrCO3 is presented as a material with high energy density for thermochemical energy storage, being an excellent material to meet the requirement for stable power generation from renewable sources.
A fuzzy adaptive admittance controller for force tracking in an uncertain contact environment
Authors: Li Zhisen , Huang Hailin , Song Xiaogang , Xu Wenfu , Li Bing
Published: August 2021

Traditional constant admittance controller (CAC) in uncertain contact environment is highly dependent on environmental location and stiffness, which are always difficult to obtain in most applications. To address this problem, a fuzzy adaptive admittance controller (FAAC) based on fuzzy inference rules is proposed in this paper. Firstly, an adaptive admittance controller (AAC) that can compensate for the admittance parameters in real time based on force error information is proposed. Secondly, a fuzzy logic loop is introduced into the adaptive term of the AAC system to reduce the overshoot when force tracking, thus creating the FAAC. The detailed design method of FAAC is presented, and the stability conditions are analysed. Finally, simulations and experiments are conducted in several dynamic environments to demonstrate the force tracking performance of the proposed controller.
Consensus problems in multiagent systems: A vector based contraction approach
Authors: Singh Bhawana , Xiong Xiaogang , Kamal Shyam , Ghosh Debdas , Ghosh Sandip
Published: August 2021

This paper addresses the exploitation of vector based contraction theory to synchronize the motion of agents in multiagent systems. The convergence analysis of the agents using this theory provides a flexible frame as the components of a vector distance norm follow less stringent conditions than classical contraction analysis. The key feature is that it encompasses the formulation of some comparison system, as a result, the problem of convergence analysis of a complex multiagent system reduces to the convergence analysis of a much simpler comparison system. Hence, despite the nonlinearities, the methods of designing consensus controls remain simple as compared to the existing literature. We address four different cases: 1) consensus of third‐order dynamics multiagent systems subjected to acceleration and input constraints; 2) consensus of multiagent systems with heterogeneous nodes under communication imperfections; 3) synchronization of multiagent systems with connected and disconnected switching topologies; 4) synchronization in networked systems with time‐varying couplings. Moreover, an effective synchronization control scheme for a class of multiagent systems with underactuated agent dynamics is developed using the method of aggregation of comparison systems. Finally, simulation results are illustrated that show the validity of the mathematical results.
High‐voltage frequency domain spectroscopy analysis of a thermally aged XLPE submarine cable under continuous and cyclic voltage based on carrier transport and polarisation characteristics
Authors: Dai Xize , Hao Jian , Jian Zheng , Liao Ruijin , Zheng Xinlong , Zhang Yiyi
Published: August 2021

In order to ensure the safe operation of submarine cables, it is of great significance to analyse the insulation state of submarine cables from the perspectives of microstructure, carrier transport characteristics and macroscopic dielectric properties. In this study, based on the high‐voltage frequency domain spectroscopy (HV‐FDS) measurement system, HV‐FDS experiments of fresh and thermally aged submarine cables were carried out under continuous (0.5, 2, 4 and 10 kV) and cyclic (2‐10‐2 kV) applied alternating voltages. Then, combining the changes of the microstructure structure of cross‐linked polyethylene (XLPE) insulation, the aggregate structure deterioration model of XLPE was proposed to discuss the physical mechanism of HV‐FDS characteristics of submarine cables under different voltages and insulation states. Results show that the HV‐FDS characteristics of submarine cables have significant voltage dependence under continuous voltage excitation. The HV‐FDS of submarine cables show memory characteristics under cyclic voltage excitation. Compared with the fresh submarine cable, the thermally aged submarine cable shows more significant voltage dependence and memory characteristics of HV‐FDS. The memory characteristics of HV‐FDS are mainly determined by the carriers transport and the interfacial polarisation caused by the accumulation of polar particles at the electrode/dielectric interface. This study covers the correlation mechanism among the microstructure, carrier transport and macroscopic HV‐FDS properties of submarine cable insulation, which lays a foundation for further research and condition evaluation of submarine cables.
Composition of organics on asteroid (101955) Bennu
Authors: Kaplan H. H. , Simon A. A. , Hamilton V. E. , Thompson M. S. , Sandford S. A. , Barucci M. A. , Cloutis E. A. , Brucato J. , Reuter D. C. , Glavin D. P. , Clark B. E. , Dworkin J. P. , Campins H. , Emery J. P. , Fornasier S. , Zou X. D. , Lauretta D. S.
Published: August 2021

Context. The Origins, Spectral Interpretation, Resource Identification, and Security-Regolith Explorer (OSIRIS-REx) mission detected an infrared absorption at 3.4 μm on near-Earth asteroid (101955) Bennu. This absorption is indicative of carbon species, including organics, on the surface.

Aims. We aim to describe the composition of the organic matter on Bennu by investigating the spectral features in detail.

Methods. We use a curated set of spectra acquired by the OSIRIS-REx Visible and InfraRed Spectrometer that have features near 3.4 μm (3.2 to 3.6 μm) attributed to organics. We assess the shapes and strengths of these absorptions in the context of laboratory spectra of extraterrestrial organics and analogs.

Results. We find spectral evidence of aromatic and aliphatic CH bonds. The absorptions are broadly consistent in shape and depth with those associated with insoluble organic matter in meteorites. Given the thermal and space weathering environments on Bennu, it is likely that the organics have not been exposed for long enough to substantially decrease the H/C and destroy all aliphatic molecules.
Evidence of the multi-thermal nature of spicular downflows
Authors: Bose Souvik , Rouppevan der Voort Luc , Joshi Jayant , Henriques Vasco M. J. , Nóbrega-Siverio Daniel , Martínez-Sykora Juan , De Pontieu Bart
Published: August 2021

Context. Spectroscopic observations of the emission lines formed in the solar transition region commonly show persistent downflows on the order of 10−15 km s−1. The cause of such downflows, however, is still not fully clear and has remained a matter of debate.

Aims. We aim to understand the cause of such downflows by studying the coronal and transition region responses to the recently reported chromospheric downflowing rapid redshifted excursions (RREs) and their impact on the heating of the solar atmosphere.

Methods. We have used two sets of coordinated data from the Swedish 1 m Solar Telescope, the Interface Region Imaging Spectrograph, and the Solar Dynamics Observatory for analyzing the response of the downflowing RREs in the transition region and corona. To provide theoretical support, we use an already existing 2.5D magnetohydrodynamic simulation of spicules performed with the Bifrost code.

Results. We find ample occurrences of downflowing RREs and show several examples of their spatio-temporal evolution, sampling multiple wavelength channels ranging from the cooler chromospheric to the hotter coronal channels. These downflowing features are thought to be likely associated with the returning components of the previously heated spicular plasma. Furthermore, the transition region Doppler shifts associated with them are close to the average redshifts observed in this region, which further implies that these flows could (partly) be responsible for the persistent downflows observed in the transition region. We also propose two mechanisms – (i) a typical upflow followed by a downflow and (ii) downflows along a loop –from the perspective of a numerical simulation that could explain the ubiquitous occurrence of such downflows. A detailed comparison between the synthetic and observed spectral characteristics reveals a distinctive match and further suggests an impact on the heating of the solar atmosphere.

Conclusions. We present evidence that suggests that at least some of the downflowing RREs are the chromospheric counterparts of the transition region and lower coronal downflows.
The H I absorption zoo: JVLA extension to z ∼ 0.4
Authors: Murthy Suma , Morganti Raffaella , Oosterloo Tom , Maccagni Filippo M.
Published: August 2021

We present an H I 21 cm absorption study of a sample of 26 radio-loud active galactic nuclei (AGN) at 0.25 < z < 0.4 carried out with the Karl G. Jansky Very Large Array. Our aim was to study the rate of incidence of H I in different classes of radio AGN, the morphology and kinematics of the detected H I, and the nature of the interaction between the H I and the radio source at these redshifts. Our sample consists of 14 sources with sizes of up to tens of kpc and 12 compact sources (< a few kpc) in the radio-power range 1025.7 W Hz−1–1026.5 W Hz−1. We detect H I in five sources, corresponding to a detection rate of ∼19%. Within the error bars, this agrees with the detection rate found at lower redshifts. We find that the rest-frame UV luminosities of most of the sources in the sample, including all the detections, are below the proposed threshold above which the H I is supposed to have been ionised. An analysis of the optical emission-line spectra of the sources shows that despite their high radio powers, about one-third of the sample, including two detections, are low-ionisation sources. The radio continuum emission from the sources detected in H I is unresolved at ∼5 to 10 kpc scales in our observations, but shows extended structure on parsec scales. We analysed the H I 21 cm absorption spectra of the detections to understand the morphology and kinematics of H I. The absorption profiles are mostly complex with widths between the nulls ranging from ∼60 km s−1 to 700 km s−1. These detections also exhibit remarkably high H I column densities in the range ∼1021 cm−2–1022 cm−2 for Tspin = 100 K and unit covering factor. Our modelling of the H I 21 cm absorption profiles suggests that in two sources the gas appears to be disturbed, and in three cases, including one with disturbed H I, the majority of the absorption is consistent with it arising from an H I disc. Despite the high radio power of our sources, we do not detect fast outflows. However, the optical emission lines in these detections show the presence of significantly disturbed gas in the nuclear regions in the form of very wide and highly blueshifted emission-line components. Since some of our detections are also low-ionisation AGN, it is quite possible that this disturbance is caused by the radio jets. Overall, our findings point towards a continuation of the low-z trends in the H I detection rate and the incidence of H I in radio AGN up to z ∼ 0.4.
Multiwavelength observations of a metric type-II event
Authors: Alissandrakis C. E. , Nindos A. , Patsourakos S. , Hillaris A.
Published: August 2021

We have studied a complex metric radio event that originated in a compact flare, observed with the ARTEMIS-JLS radiospectrograph on February 12, 2010. The event was associated with a surge observed at 195 and 304 Å and with a coronal mass ejection observed by instruments on board STEREO A and B near the eastern and western limbs respectively. On the disk the event was observed at ten frequencies by the Nançay Radioheliograph (NRH), in Hαby the Catania observatory, in soft X-rays by GOES SXI and Hinode XRT, and in hard X-rays by RHESSI. We combined these data, together with MDI longitudinal magnetograms, to get as complete a picture of the event as possible. Our emphasis is on two type-II bursts that occurred near respective maxima in the GOES light curves. The first, associated with the main peak of the event, showed an impressive fundamental-harmonic structure, while the emission of the second consisted of three well-separated bands with superposed pulsations. Using positional information for the type-IIs from the NRH and triangulation from STEREO A and B, we found that the type-IIs were associated neither with the surge nor with the disruption of a nearby streamer, but rather with an extreme ultraviolet (EUV) wave probably initiated by the surge. The fundamental-harmonic structure of the first type-II showed a band split corresponding to a magnetic field strength of 18 G, a frequency ratio of 1.95 and a delay of 0.23−0.65 s of the fundamental with respect to the harmonic; moreover it became stationary shortly after its start and then drifted again. The pulsations superposed on the second type-II were broadband and had started before the burst. In addition, we detected another pulsating source, also before the second type-II, polarized in the opposite sense; the pulsations in the two sources were out of phase and hence hardly detectable in the dynamic spectrum. The pulsations had a measurable reverse frequency drift of about 2 s−1.
Sequencing conserved region of endangered speciesCeltis caucasicaWilld
Authors: Kairova Markhabat , Sitpayeva Gulnara
Published: August 2021

The rarest species of relict ironwoodC. caucasicaWilld. is naturally occurred on the Ile-Alatau Mountains but very little is known about genetic diversity and distribution and size of its populations in Kazakhstan. In during the sampling expedition were found two additional plant populations in Dzungarian and Kyrgyz Alatau Ranges. The objective of this work was targeted towards sequencing ITS region ofC. caucasicaand compare the obtained nucleotide sequence with available data on NCBI GeneBank for confident species identification. The identity ofC. caucasicasequence and availableC. australisandC. bungeanasequences was 93.87% and less. It could be associated with absence sequences producing significant alignments with the studied ironwood sequence and important deposited sequences of GenBank lacking Latin binominals is from environmental samples. Clarifying taxonomical status species and subspecies is difficult by morphological data and molecular markers should be used to correct identifying an endangered species ofC. caucasicagrowing in the east-southern and the south regions of Kazakhstan and providing direction to the conservation management of the plant.
Accumulation of chemical elements in tree waste ofPinus sylvestrisL. growing in various ecological zones
Authors: Kolmogorova Elena
Published: August 2021

We investigated the pattern of phosphorus, nitrogen and ashes accumulation in tree waste ofPinus sylvestrisL. growing in various ecological zones. The studied areas were located in the Kemerovo Region: on flood-land of the Tom River (the Kuzbass Botanical Garden) and on the waste dump of the Kedrovsky open-cast mine. It was shown that the chemical composition of tree waste ofPinus sylvestrisL. is correlated with ecological conditions of its vegetation. So, the tree waste ofPinus sylvestrisL. growing on the waste dump is characterized by three-fold increased level of nitrogen compared to ones from the Kuzbass Botanical Garden. The concentration of phosphorus and ashes showed no differences between groups. We suggested that the diversity in destruction of tree waste proceeding in different conditions and microbial cenosis leads to differentiated accumulation of chemical elements in the tree waste.
Fruiting of macromycetes in artificial plantations ofPinus sylvestrisL. on the waste dump of the Kedrovsky open-cast coal mine
Authors: Legoshchina Olga
Published: August 2021

The quantitative registration of macromycete fruiting bodies was performed during two field seasons in the pine plantations of recultivated waste dump (experimental area) and in the pine forests on zonal soils (control area). The average quantity of carpophore macromycetes on the experimental area during two years of research exceeded ones on the control area by 41%. The field season of 2020 was characterized by significantly increased productivity of fungi in the studied areas; two peaks of mass fruiting of macromycetes were registrate. The maximum frequency of fruiting bodies of higher fungi was discovered in the autumn peak of mass fruiting mediated mainly by fair appearance of symbiotrophic fungi. Both studied areas in the different years of research were characterized by oppositely processes providing the distribution of carpophore macromycetes in pine plantations with different crown density (sparse, medium and dense). Taking into account the crown projection zones, the maximum frequency of macromycete fruiting bodies was located in the near-crown and outer zones ofPinus sylvestrisL. trees.
The influence of soil microorganisms on heavy metal content in the substrate of waste rock dumps
Authors: Makeeva Natalia , Neverova Olga
Published: August 2021

The environmental effects of mining and its impact on natural resources are of a holistic nature. One of the modern methods employed for the remediation of technogenically disturbed soils is the application of microorganisms. This paper studies the impact made by soil microorganisms on the accumulation rate of heavy metals in the substrate of waste rock dumps in the process of soil reclamation. Suspensions of soil microorganisms (microorganisms utilising mineral nitrogen forms / MUMN; microorganisms decomposing silicates / MDS; microscopic fungi / MF) were applied to the rock dump surface. Separate groups as well as their combinations were applied. The heavy metal content analysis did not indicate a significant exceedance of the maximum allowable concentration limits (MACL) in the soil of the waste rock. The only metal whose content exceeded the maximum admissible concentration limits was nickel. It has found that the application of microorganisms influences the concentration of several heavy metals due to pH level changes of the rock dump soil.
Methodology for assessing water quality using a neural network
Authors: Schastlivtsev Evgeniy , Yukina Natalia , Kharlampenkov Ivan
Published: August 2021

A methodology for assessing the quality of surface and groundwater is proposed, using artificial intelligence methods, in particular, a fully connected neural network. Preliminary testing was carried out on water objects and a sufficiently high percentage of model accuracy was obtained.
Effectiveness of winter wheat cultivation in adaptive crop rotation on chernozem typical
Authors: Prushchik Ivan , Khlupina Svetlana
Published: August 2021

The paper presents the results of research to assess the efficiency of winter wheat (Triticum aestivum L.) cultivation in adaptive crop rotations on typical chernozem. The crop yield have analyzed for three different crop rotations (grain-fallow, grain-grass-row, and grain-grass) in comparison with a monoculture on a stationary multifactorial field experiment on physical modeling of the farming system of the FSBSI “Kursk FARC” (Kursk region, Medvensky district). It was determined that the maximum yield was obtained in grain-and-row crop rotation; on average, over three years of research, the increase in it was 1.71 t/ha. Statistical data processing has carried out and correlations between the weather conditions of the year and the yield of winter wheat has revealed. Thus, a moderate direct relationship (r = 0.65) was established with atmospheric precipitation, and a moderate inverse relationship with the sum of effective temperatures (r = 0.58). Indicators of economic efficiency of winter wheat cultivation have calculated, both for monoculture and for three types of crop rotations. The lowest cost of winter wheat grain – 5926.94 t/ha – was recorded in grain-fallow crop rotation, which provided the highest net income of 12056.26 and the highest profitability among all options – 68.72%.