bluuebunny/crossref_metadata_2025 huggingface dataset:
Gaining insight into the assimilated diet of small bear populations by stable isotope analysis
Authors: Careddu Giulio , Ciucci Paolo , Mondovì Stella , Calizza Edoardo , Rossi Loreto , Costantini Maria Letizia
Published: July 2021

Apennine brown bears (Ursus arctos marsicanus) survive in an isolated and critically endangered population, and their food habits have been studied using traditional scat analysis. To complement current dietary knowledge, we applied Stable Isotope Analysis (SIA) to non-invasively collected bear hairs that had been individually recognized through multilocus genotyping. We analysed carbon (δ13C) and nitrogen (δ15N) stable isotopes of hair sections and bear key foods in a Bayesian mixing models framework to reconstruct the assimilated diet on a seasonal basis and to assess gender and management status effects. In total, we analysed 34 different seasonal bear key foods and 35 hair samples belonging to 27 different bears (16 females and 11 males) collected during a population survey in 2014. Most bears showed wide δ15N and δ13C ranges and individual differences in seasonal isotopic patterns. Vegetable matter (herbs, fleshy fruits and hard mast) represented the major component of the assimilated diet across the dietary seasons, whereas vegetable crops were rarely and C4 plants (i.e., corn) never consumed. We confirmed an overall low consumption of large mammals by Apennine bears consistently between sexes, with highest values in spring followed by early summer but null in the other seasons. We also confirmed that consumption of fleshy fruits peaked in late summer, when wild predominated over cultivated fleshy fruits, even though the latter tended to be consumed in higher proportion in autumn. Male bears had higher δ 15N values than females in spring and autumn. Our findings also hint at additional differences in the assimilated diet between sexes, with females likely consuming more herbs during spring, ants during early summer, and hard mast during fall compared to males. In addition, although effect sizes were small and credibility intervals overlapped considerably, management bears on average were 0.9‰ lower in δ 13C and 2.9‰ higher in δ 15N compared to non-management bears, with differences in isotopic values between the two bear categories peaking in autumn. While non-management bears consumed more herbs, wild fleshy fruits, and hard mast, management bears tended to consume higher proportions of cultivated fruits, ants, and large mammals, possibly including livestock. Although multi-year sampling and larger sample sizes are needed to support our findings, our application confirms that SIA can effectively integrate previous knowledge and be efficiently conducted using samples non-invasively collected during population surveys.
Integrative taxonomy and phylogeography of Telenomus remus (Scelionidae), with the first record of natural parasitism of Spodoptera spp. in Brazil
Authors: Wengrat Ana P. G. S. , Coelho Junior Aloisio , Parra Jose R. P. , Takahashi Tamara A. , Foerster Luis A. , Corrêa Alberto S. , Polaszek Andrew , Johnson Norman F. , Costa Valmir A. , Zucchi Roberto A.
Published: July 2021

The egg parasitoid Telenomus remus (Hymenoptera: Scelionidae) has been investigated for classical and applied biological control of noctuid pests, especially Spodoptera (Lepidoptera: Noctuidae) species. Although T. remus was introduced into Brazil over three decades ago for classical biological control of S. frugiperda, this wasp has not been recorded as established in corn or soybean crops. We used an integrative approach to identify T. remus, combining a taxonomic key based on the male genitalia with DNA barcoding, using a cytochrome c oxidase subunit I mitochondrial gene fragment. This is the first report of natural parasitism of T. remus on S. frugiperda and S. cosmioides eggs at two locations in Brazil. We also confirmed that the T. remus lineage in Brazil derives from a strain in Venezuela (originally from Papua New Guinea and introduced into the Americas, Africa, and Asia). The occurrence of T. remus parasitizing S. frugiperda and S. cosmioides eggs in field conditions, not associated with inundative releases, suggests that the species has managed to establish itself in the field in Brazil. This opens possibilities for future biological control programs, since T. remus shows good potential for mass rearing and egg parasitism of important agricultural pests such as Spodoptera species.
A myostatin-CCL20–CCR6 axis regulates Th17 cell recruitment to inflamed joints in experimental arthritis
Authors: Fennen Michelle , Weinhage Toni , Kracke Vanessa , Intemann Johanna , Varga Georg , Wehmeyer Corinna , Foell Dirk , Korb-Pap Adelheid , Pap Thomas , Dankbar Berno
Published: July 2021

The interactions of fibroblast-like synoviocyte (FLS)-derived pro-inflammatory cytokines/chemokines and immune cells support the recruitment and activation of inflammatory cells in RA. Here, we show for the first time that the classical myokine myostatin (GDF-8) is involved in the recruitment of Th17 cells to inflammatory sites thereby regulating joint inflammation in a mouse model of TNFalpha-mediated chronic arthritis. Mechanistically, myostatin-deficiency leads to decreased levels of the chemokine CCL20 which is associated with less infiltration of Th17 cells into the inflamed joints. In vitro, myostatin alone or in combination with IL-17A enhances the secretion of CCL20 by FLS whereas myostatin-deficiency reduces CCL20 secretion, associated with an altered transmigration of Th17 cells. Thus, the communication between activated FLS and Th17 cells through myostatin and IL-17A may likely contribute to a vicious cycle of inflammation, accounting for the persistence of joint inflammation in chronic arthritis. Blockade of the CCL20–CCR6 axis by inhibition of myostatin may, therefore, be a promising treatment option for chronic inflammatory diseases such as arthritis.
A hybrid CNN-LSTM model for pre-miRNA classification
Authors: Tasdelen Abdulkadir , Sen Baha
Published: July 2021

miRNAs (or microRNAs) are small, endogenous, and noncoding RNAs construct of about 22 nucleotides. Cumulative evidence from biological experiments shows that miRNAs play a fundamental and important role in various biological processes. Therefore, the classification of miRNA is a critical problem in computational biology. Due to the short length of mature miRNAs, many researchers are working on precursor miRNAs (pre-miRNAs) with longer sequences and more structural features. Pre-miRNAs can be divided into two groups as mirtrons and canonical miRNAs in terms of biogenesis differences. Compared to mirtrons, canonical miRNAs are more conserved and easier to be identified. Many existing pre-miRNA classification methods rely on manual feature extraction. Moreover, these methods focus on either sequential structure or spatial structure of pre-miRNAs. To overcome the limitations of previous models, we propose a nucleotide-level hybrid deep learning method based on a CNN and LSTM network together. The prediction resulted in 0.943 (%95 CI ± 0.014) accuracy, 0.935 (%95 CI ± 0.016) sensitivity, 0.948 (%95 CI ± 0.029) specificity, 0.925 (%95 CI ± 0.016) F1 Score and 0.880 (%95 CI ± 0.028) Matthews Correlation Coefficient. When compared to the closest results, our proposed method revealed the best results for Acc., F1 Score, MCC. These were 2.51%, 1.00%, and 2.43% higher than the closest ones, respectively. The mean of sensitivity ranked first like Linear Discriminant Analysis. The results indicate that the hybrid CNN and LSTM networks can be employed to achieve better performance for pre-miRNA classification. In future work, we study on investigation of new classification models that deliver better performance in terms of all the evaluation criteria.
Engineering of the genome editing protein Cas9 to slide along DNA
Authors: Banerjee Trishit , Takahashi Hiroto , Subekti Dwiky Rendra Graha , Kamagata Kiyoto
Published: July 2021

The genome editing protein Cas9 faces engineering challenges in improving off–target DNA cleavage and low editing efficiency. In this study, we aimed to engineer Cas9 to be able to slide along DNA, which might facilitate genome editing and reduce off-target cleavage. We used two approaches to achieve this: reducing the sliding friction along DNA by removing the interactions of Cas9 residues with DNA and facilitating sliding by introducing the sliding-promoting tail of Nhp6A. Seven engineered mutants of Cas9 were prepared, and their performance was tested using single-molecule fluorescence microscopy. Comparison of the mutations enabled the identification of key residues of Cas9 to enhance the sliding along DNA in the presence and absence of single guide RNA (sgRNA). The attachment of the tail to Cas9 mutants enhanced sliding along DNA, particularly in the presence of sgRNA. Together, using the proposed approaches, the sliding ability of Cas9 was improved up to eightfold in the presence of sgRNA. A sliding model of Cas9 and its engineering action are discussed herein.
The electronic origins of the “rare earth” texture effect in magnesium alloys
Authors: Mahjoub Reza , Stanford Nikki
Published: July 2021

Although magnesium alloys are lightweight, recyclable and relatively cheap, they suffer from poor ductility. This can be improved by the addition of rare earth (RE) elements, and this is now a well-established criterion for wrought alloy design. It is notable that this behavior is largely restricted to the lanthanides, but no hypothesis is yet available to explain why other elements do not have the same effect. To answer this question, ab initio simulations of crystallographically complex boundaries have been undertaken to examine the electronic origin of the RE effect. While the electronic structure provided strong bonding between the RE elements and their Mg surroundings, local disruption in atomic arrangement at the grain boundaries was found to modify this effect. This work shows quantifiable changes in electronic structure of solutes resulting from grain boundary crystallography, and is suggested to be a contributing factor to the RE texture effect.
Shifts in ecological strategy spectra of typical forest vegetation types across four climatic zones
Authors: Han Xin , Huang Jihong , Zang Runguo
Published: July 2021

Ecological strategy spectrum is the relative proportion of species in different categories of ecological strategies in a biotic community. Here, we explored ecological strategy spectra in typical forest vegetation types across four climatic zones in China. We classified ecological strategy categories by using the “StrateFy” ordination method based on three leaf functional traits. Results showed that the predominant ecological strategies of species in the tropical rainforest were CS-selected, and the predominant categories in the evergreen-deciduous broadleaved mixed forest and warm-temperate coniferous-broadleaved mixed forest were CSR and S/CSR categories respectively, whereas those in the cold-temperate coniferous forest were the S-selected ones. Ecological strategy richness of forest vegetation decreased significantly with the increase of latitude. The categories of ecological strategies with more component S increased while those with more component C decreased with the change of typical forest vegetation types from tropical rainforest through evergreen-deciduous broadleaved mixed forest and warm-temperate coniferous-broadleaved mixed forest to cool-temperate coniferous forest. Our findings highlight the usefulness of Grime’s C-S-R scheme for predicting the responses of vegetation to environmental changes, and the results are helpful in further elucidating species coexistence and community assembly in varied climatic and geographic settings.
Cryo-electron tomography provides topological insights into mutant huntingtin exon 1 and polyQ aggregates
Authors: Galaz-Montoya Jesús G. , Shahmoradian Sarah H. , Shen Koning , Frydman Judith , Chiu Wah
Published: July 2021

Huntington disease (HD) is a neurodegenerative trinucleotide repeat disorder caused by an expanded poly-glutamine (polyQ) tract in the mutant huntingtin (mHTT) protein. The formation and topology of filamentous mHTT inclusions in the brain (hallmarks of HD implicated in neurotoxicity) remain elusive. Using cryo-electron tomography and subtomogram averaging, here we show that mHTT exon 1 and polyQ-only aggregates in vitro are structurally heterogenous and filamentous, similar to prior observations with other methods. Yet, we find filaments in both types of aggregates under ~2 nm in width, thinner than previously reported, and regions forming large sheets. In addition, our data show a prevalent subpopulation of filaments exhibiting a lumpy slab morphology in both aggregates, supportive of the polyQ core model. This provides a basis for future cryoET studies of various aggregated mHTT and polyQ constructs to improve their structure-based modeling as well as their identification in cells without fusion tags.
A reference-grade genome identifies salt-tolerance genes from the salt-secreting mangrove species Avicennia marina
Authors: Natarajan Purushothaman , Murugesan Ashok Kumar , Govindan Ganesan , Gopalakrishnan Ayyaru , Kumar Ravichandiran , Duraisamy Purushothaman , Balaji Raju , Tanuja  , Shyamli Puhan Sushree , Parida Ajay K. , Parani Madasamy
Published: July 2021

Water scarcity and salinity are major challenges facing agriculture today, which can be addressed by engineering plants to grow in the boundless seawater. Understanding the mangrove plants at the molecular level will be necessary for developing such highly salt-tolerant agricultural crops. With this objective, we sequenced the genome of a salt-secreting and extraordinarily salt-tolerant mangrove species,Avicennia marina, that grows optimally in 75% seawater and tolerates >250% seawater. Our reference-grade ~457 Mb genome contains 31 scaffolds corresponding to its chromosomes. We identified 31,477 protein-coding genes and a salinome consisting of 3246 salinity-responsive genes and homologs of 614 experimentally validated salinity tolerance genes. The salinome provides a strong foundation to understand the molecular mechanisms of salinity tolerance in plants and breeding crops suitable for seawater farming.
βA3/A1-crystallin regulates apical polarity and EGFR endocytosis in retinal pigmented epithelial cells
Authors: Shang Peng , Stepicheva Nadezda , Teel Kenneth , McCauley Austin , Fitting Christopher Scott , Hose Stacey , Grebe Rhonda , Yazdankhah Meysam , Ghosh Sayan , Liu Haitao , Strizhakova Anastasia , Weiss Joseph , Bhutto Imran A. , Lutty Gerard A. , Jayagopal Ashwath , Qian Jiang , Sahel José-Alain , Samuel Zigler J. , Handa James T. , Sergeev Yuri , Rajala Raju V. S. , Watkins Simon , Sinha Debasish
Published: July 2021

The retinal pigmented epithelium (RPE) is a monolayer of multifunctional cells located at the back of the eye. High membrane turnover and polarization, including formation of actin-based apical microvilli, are essential for RPE function and retinal health. Herein, we demonstrate an important role for βA3/A1-crystallin in RPE. βA3/A1-crystallin deficiency leads to clathrin-mediated epidermal growth factor receptor (EGFR) endocytosis abnormalities and actin network disruption at the apical side that result in RPE polarity disruption and degeneration. We found that βA3/A1-crystallin binds to phosphatidylinositol transfer protein (PITPβ) and that βA3/A1-crystallin deficiency diminishes phosphatidylinositol 4,5-biphosphate (PI(4,5)P2), thus probably decreasing ezrin phosphorylation, EGFR activation, internalization, and degradation. We propose that βA3/A1-crystallin acquired its RPE function before evolving as a structural element in the lens, and that in the RPE, it modulates the PI(4,5)P2 pool through PITPβ/PLC signaling axis, coordinates EGFR activation, regulates ezrin phosphorylation and ultimately the cell polarity.
Integrating circular economy in urban Amazon
Authors: Paes Michel Xocaira , Campos-Silva João Vitor , de Oliveira José Antonio Puppim
Published: July 2021

The Amazon hosts a large biological and cultural diversity with a deeply established knowledge of natural resource management. Nevertheless, many parts of the Amazon are increasingly urban, lacking basic urban services, such as waste management. In this context, the design of new development pathways based on the principles of the circular economy is a promising alternative to align biodiversity conservation and urban changes. Here, based on an analysis of Carauari municipality in the western Brazilian Amazon, we discuss how the principles of the circular economy can be integrated in the Amazonian urban development frontline using the existing co-management organizations.
Insights into the synergistic influence of [Emim][OAc] and AgOAc for the hydration of propargylic alcohols to α-hydroxy ketones in the presence of CO2
Authors: Hu Yuhang , Dong Shuya , Zhang Zhengkun , Wang Li , Zhang Jinglai
Published: July 2021

A catalytic mechanism including metals, ionic liquids, and co-catalysts is elucidated for the first time.
Single-crystal-to-single-crystal transformations among three Mn-MOFs containing different water molecules induced by reaction time: crystal structures and proton conductivities
Authors: Zhou Chuan-Cong , Liu Hou-Ting , Ding Li , Lu Jing , Wang Su-Na , Li Yun-Wu
Published: July 2021

Three MOFs were obtained, which can SC–SC transform into each other. The different amounts of water molecules in their formulas led to differences in crystal structures, porosity, hydrophilicity and proton conductivity.
Steric and electronic effects of ligand substitution on redox-active Fe4S4-based coordination polymers
Authors: Salinas Omar , Xie Jiaze , Papoular Robert J. , Horwitz Noah E. , Elkaim Erik , Filatov Alexander S. , Anderson John S.
Published: July 2021

Linker methylation in 1D coordination polymers of iron–sulfur clusters modifies crystallinity and electronic structure.
An amorphous hierarchical MnO2/acetylene black composite with boosted rate performance as an anode for lithium-ion batteries
Authors: Zhang Xiaole , Li Song , Wang Shenghe , Wang Zhenxu , Wen Zhongsheng , Ji Shijun , Sun Juncai
Published: July 2021

An amorphous hierarchical MnO2/AB composite prepared via a ball-milling method exhibited excellent coulombic efficiency and rate performance.
Involvement of a unique chemodosimeter in the selective estimation of noxious cyanide in common water hyacinth (Eichhornia crassipes): an environmental refinement
Authors: Saha Shrabani , Ghosh Priyotosh , Mondal Paritosh , Chattopadhyay Ansuman , Sahoo Prithidipa
Published: July 2021

A naphthaldehyde-pyridoxal conjugated chemodosimeter (NPLC) was developed and employed for the sensitive and selective detection and estimation of cyanide in common water hyacinth (Eichhornia crassipes) used in the phytoremediation process.
Impact of subtle change in branched amino acid on the assembly and properties of perylene bisimides hydrogels
Authors: Egan Jacquelyn G. , Brodie Glen , McDowall Daniel , Smith Andrew J. , Edwards-Gayle Charlotte J. C. , Draper Emily R.
Published: July 2021

We investigate how apparent slight changes to the chemical structure of amino acid-functionalised perylene bisimides (PBIs) affect the self-assembled aggregates formed and their resulting physical and optical properties.
A nanoimprinted artificial engram device
Authors: Li Xuesong , Zeng Pan , Wang Feilong , Zhang Dai , Zhou Yi , Liang Rongqing , Ou Qiongrong , Wu Xiang , Zhang Shuyu
Published: July 2021

A nanoimprinted artificial engram device is presented, which meets all the requirements for engrams including synaptic plasticity, long memory storage time, asymmetric memorizing-forgetting behavior and measurable changes and responses.
Metal–metal bonds in polyoxometalate chemistry
Authors: Kondinski Aleksandar
Published: July 2021

Metal-metal bonds are typically present in metal clusters and absent in polyoxometalates. Our ultimate understanding of their emergence in polyoxometalates paves the way to new technologies.
Transition metal-based catalysts for electrochemical water splitting at high current density: current status and perspectives
Authors: Li Shasha , Li Enze , An Xiaowei , Hao Xiaogang , Jiang Zhongqing , Guan Guoqing
Published: July 2021

Current popular transition metal-based electrocatalysts developed for HER/OER in water splitting at high current density are critically reviewed and discussed.
Microfluidic synthesis of pyrrolidin-2-ones via photoinduced organocatalyzed cyclization of styrene, α-bromoalkyl esters and primary amines
Authors: Wei Minghui , Zhang Jingming , Liu Chengkou , He Wei , Wang Tingyu , Yang Xiaobing , Yang Zhao , Fang Zheng , Guo Kai
Published: July 2021

A green and efficient reaction route for the synthesis of pyrrolidin-2-ones via photoinduced organocatalyzed three-component cyclization of styrene, tertiary α-bromoalkyl esters and primary amines in a microchannel reactor has been developed.
Dynamic evolution of supramolecular chirality manipulated by H-bonded coassembly and photoisomerism
Authors: Cheng Qiuhong , Hao Aiyou , Xing Pengyao
Published: July 2021

Dynamic evolution of supramolecular chirality inversion and the inversion of corresponding circularly polarized luminescence via the multiple-constituent coassemblies driven by hydrogen bonds was realized.
Synthetic applications of α,α-difluoroarylacetic acids and salts via decarboxylative functionalization
Authors: Mei Wenqiang , Kong Yilin , Yan Guobing
Published: July 2021

α,α-Difluoroarylacetic acids are stable, inexpensive and readily available building blocks which can be used to access various difluoromethylated aryl motifs via decarboxylative functionalization for the formation of carbon–carbon and carbon-heteroatom (F, O, S) bonds.
Composition-tuned MAPbBr3 nanoparticles with addition of Cs+ cations for improved photoluminescence
Authors: Dintakurti Sai S. H. , Vashishtha Parth , Giovanni David , Fang Yanan , Foo Norton , Shen Zexiang , Guet Claude , Sum Tze Chien , White Tim
Published: July 2021

Structural and optical properties of MAxCs1−xPbBr3 mixed cation colloidal nanoparticles with 13 mol% Cs composition exhibiting the longest charge carrier lifetime and enhancement in radiative pathways.
Increasing saturation: development of broadly applicable photocatalytic Csp2–Csp3 cross-couplings of alkyl trifluoroborates and (hetero)aryl bromides for array synthesis
Authors: Cauley Anthony N. , Sezen-Edmonds Melda , Simmons Eric M. , Cavallaro Cullen L.
Published: July 2021

HTE was used to systematically investigate the reaction of alkyl trifluoroborates and aryl bromides under photocatalytic conditions. General conditions were identified for coupling of activated primary, benzylic and secondary alkyl trifluoroborates.
Recent advances in sustainable production and catalytic transformations of fatty acid methyl esters
Authors: Belousov Artem S. , Esipovich Anton L. , Kanakov Evgeny A. , Otopkova Ksenia V.
Published: July 2021

This review highlights the recent advances in the sustainable production of fatty acid methyl esters and their transformations, including oxidation, amidation, hydrogenation, deoxygenation, ethoxylation, metathesis, and isomerisation reactions.
Silk granular hydrogels self-reinforced with regenerated silk fibroin fibers
Authors: Wyss Céline Samira , Karami Peyman , Demongeot Adrien , Bourban Pierre-Etienne , Pioletti Dominique P.
Published: July 2021

The swelling of microgels is used to concentrate the surrounding solution and regenerate silk fibroin in situ. The obtained materials are self-reinforced composite granular hydrogels with high stability, strength and toughness.
Boosting the Zn-ion transfer kinetics to stabilize the Zn metal interface for high-performance rechargeable Zn-ion batteries
Authors: Hong Lin , Wu Xiuming , Ma Chao , Huang Wei , Zhou Yongfeng , Wang Kai-Xue , Chen Jie-Sheng
Published: July 2021

An artificial SEI film based on Zn-intercalated montmorillonite was designed to tune the deposition behaviour of Zn2+ ions on the surface of Zn anode.
Highly dispersed antimonene oxide quantum dots and their hybrid gel glasses for broadband nonlinear optical limiting
Authors: Xing Fangyuan , Wang Yue , Wang Jingjing , Zhou Shuyun , Zhao Junlong , Xie Zheng
Published: July 2021

Highly dispersed antimonene oxide quantum dots with broadband nonlinear optical limiting performance in liquid and solid states were illustrated.
Recent advancements in the exploitation of the gut microbiome in the diagnosis and treatment of colorectal cancer
Authors: Stott Katie J. , Phillips Bethan , Parry Lee , May Stephanie
Published: July 2021

Over the last few decades it has been established that the complex interaction between the host and the multitude of organisms that compose the intestinal microbiota plays an important role in human metabolic health and disease. Whilst there is no defined consensus on the composition of a healthy microbiome due to confounding factors such as ethnicity, geographical locations, age and sex, there are undoubtably populations of microbes that are consistently dysregulated in gut diseases including colorectal cancer (CRC). In this review, we discuss the most recent advances in the application of the gut microbiota, not just bacteria, and derived microbial compounds in the diagnosis of CRC and the potential to exploit microbes as novel agents in the management and treatment of CRC. We highlight examples of the microbiota, and their derivatives, that have the potential to become standalone diagnostic tools or be used in combination with current screening techniques to improve sensitivity and specificity for earlier CRC diagnoses and provide a perspective on their potential as biotherapeutics with translatability to clinical trials.
Analytic solution for the electrostatic potential of the solar wind
Authors: Osuna Alcalaya Pedro , Zouganelis Ioannis , Rodríguez Pacheco Javier
Published: July 2021

Context. Some kinetic models of the solar wind, such as the exospheric ones, make certain assumptions about the solar plasma, which for modelling purposes is generally considered collisionless and quasi-neutral. They also assume specific distribution functions for the electron and proton populations from which the fundamental properties of the plasma, including the density, are calculated using the moment integrals. Imposing the quasi-neutrality condition leads to the presence of an ambipolar electrostatic field, which is responsible for the acceleration of the wind. Usually, the calculation of the moment integrals is complicated by the fact that most kinetic models assume different trajectories for the solar wind components, separating the integrals into chunks corresponding to the pitch angles defining the trajectories. Hence, up to now all these integrals and therefore the plasma fundamental quantities have been calculated numerically.

Aims. A new model is presented that makes use of similar assumptions to other kinetic collisionless models but does not need to impose the separation of the populations in different trajectories for the calculation of the integrals. As a consequence, an analytic solution for the electrostatic potential of the solar wind valid for all distances is found.

Methods. A kinetic collisionless approach was used to characterise the solar wind plasma. A single equation for the electrostatic potential function was found assuming certain distribution functions (Maxwellian or non-thermal such as Kappa), which include an unknown electrostatic potential, calculating the density integral for those distribution functions and making those densities equal for electrons and protons.

Results. An analytic solution for the electrostatic potential as a function of radial distance is found (for the first time for all distances) and shown to produce a non-monotonic total potential, which is compatible with other models like the exospheric ones whose electrostatic potential drives the acceleration of the solar wind. This expression can now be used, in a straightforward way, to provide insight into the importance of the electron distribution functions to shape the electrostatic potential of thermal solar-like outflows.
Spectro-imagery of an active tornado-like prominence: Formation and evolution
Authors: Barczynski Krzysztof , Schmieder Brigitte , Peat Aaron W. , Labrosse Nicolas , Mein Pierre , Mein Nicole
Published: July 2021

Context. The dynamical nature of fine structures in prominences remains an open issue, including rotating flows in tornado prominences. While the Atmospheric Imaging Assembly imager aboard the Solar Dynamics Observatory allowed us to follow the global structure of a tornado-like prominence for five hours, the Interface Region Imaging Spectrograph, and the Multichannel Subtractive Double Pass spectrograph permitted to obtain plasma diagnostics of its fine structures.

Aims. We aim to address two questions. Firstly, is the observed plasma rotation conceptually acceptable in a flux rope magnetic support configuration with dips? Secondly, how is the plasma density distributed in the tornado-like prominence?

Methods. We calculated line-of-sight velocities and non-thermal line widths using Gaussian fitting for Mg II lines and the bisector method for Hα line. We determined the electron density from Mg II line integrated intensities and profile fitting methods using 1D non-LTE radiative transfer theory models.

Results. The global structure of the prominence observed in Hα, and Mg II h, and k line fits with a magnetic field structure configuration with dips. Coherent Doppler shifts in redshifted and blueshifted areas observed in both lines were detected along rapidly-changing vertical and horizontal structures. However, the tornado at the top of the prominence consists of multiple fine threads with opposite flows, suggesting counter-streaming flows rather than rotation. Surprisingly we found that the electron density at the top of the prominence could be larger (1011 cm−3) than in the inner part of the prominence.

Conclusions. We suggest that the tornado is in a formation state with cooling of hot plasma in a first phase, and following that, a phase of leakage of the formed blobs with large transverse flows of material along long loops extended away from the UV prominence top. The existence of such long magnetic field lines on both sides of the prominence would stop the tornado-like prominence from really turning around its axis.
Effect of silicon carbide modifiers on the physical-mechanical properties of gray cast iron and cast iron with spheroidal graphite
Authors: Poluboyarov Vladimir A. , Cherepanov Anatoliy N. , Kuznetsov Viktor A. , Korotaeva Zoya A. , Zhdanok Alexander A.
Published: July 2021

The influence of mechanochemically produced modifiers on the properties of cast iron at out-of-furnace modification has been studied. Short-term treatment in mechanochemical activators makes it possible to produce composite modifiers, which are wetted with iron melts, are uniformly distributed therein and effectively influence the crystallization processes. The effect of a modifier based on silicon carbide and chromium (as a protector metal) on the physical-mechanical properties of gray cast-iron and cast-iron with spheroidal graphite is considered. The introduction of SiC in the amount of 0.01-0.1 wt.% into gray cast iron causes the formation of mainly perlitic structure and, as a consequence, an increase in strength, hardness and wear resistance. For SiC content 0.1 wt.%, the tensile strength of GG-15 samples increased by 22.7%, GG-25 by 8%. The maximal increase in the hardness is observed for SiC concentration: for GG-15 – 0.1, for GG-25 – 0.01 wt.%. The GG-25 sample with 0.1 wt.% SiC exhibited the highest wear resistance. The introduction of SiC (0.01 – 0.1 wt.%) into cast iron with spheroidal graphite causes an increase in ferrite content, which promotes a substantial increase in impact viscosity and wear resistance (the highest wear resistance is observed with the introduction of 0.05 wt.% SiC).
Crystal structure and electrochemical properties of phosphosulphate NaFe2PO4(SO4)2
Authors: Shindrov Alexander A. , Kabanov Artem A. , Kosova Nina V.
Published: July 2021

NASICON-type NaFe2(PO4)(SO4)2 (NFPS) electrode material is successfully synthesized via a rheological route. DSC/TG analysis shows that it is thermally stable up to 760 °C. A carbon composite NFPS/C was obtained using ball milling. NFPS and NFPS/C were investigated as cathode and anode materials for sodium-ion batteries. Analysis of migration paths was performed by the Voronoi-Dirichlet partition technique to determine all possible Na+ ion migration paths. The diffusion coefficient, estimated by GITT, is in the 10-12-10-13 cm2∙s-1 range, which corresponds to the fast Na+ ion migration in the structure. According to calculations, NFPS is a wide band gap material, which indicates its poor electrical conductivity.
Assessment of CO2 flooding as enhanced oil recovery
Authors: Makhambetov Akhat , Azilkhanov Nursultan
Published: July 2021

This article discusses evaluating CO2 injection as an enhanced oil recovery method. Carbon dioxide injection is a secondary and tertiary enhanced oil recovery method and is used in the final stage of development. Carbon dioxide mixes well with oil and can dissolve heavy components. Also, CO2 maintains reservoir pressure, which prevents the flow rate from dropping. In order for carbon dioxide and oil to mix, it must be brought to a critical state by increasing the temperature and pressure. After reaching the required conditions, both substances are fully compatible. The result of this combination is a medium that can easily seep through a porous medium. In fact, gas injection would be appropriate to use in a carbonate reservoir, and in our country and all over the world there are many oil fields that are located in carbonate rock. This work is based on data on a field located in the Krasnoyarsk region, which is part of the Angara fold zones. The field itself is represented mainly by carbonate reservoirs. Also, application of this method for Kazakhstan oilfield will be considered, using an example Zhetybay oilfield.
Hydrogenation of benzene and toluene over supported rhodium and rhodium-gold catalysts
Authors: Konuspayev Sapar , Shaimardan Minavar , Annas Nurlan , Abildin T.S. , Suleimenov Y.Y.
Published: July 2021

Rhodium and rhodium-gold catalysts supported on amorphous aluminosilicates (ASA), titanium dioxide (rutile, TiO2) was prepared in two different ways: absorption and colloidal method. The catalysts were characterized by an inductively coupled plasma optical emission spectrometer (ICP-OES), transmission electron microscopy (TEM) and X-ray diffraction (XRD). The activity and selectivity of the prepared catalysts were tested by the hydrogenation of benzene and toluene. Hydrogenation was conducted at a pressure of 4 MPa and a temperature 80 °C. The bimetallic Rh-Au/ASA catalyst prepared by the absorption method showed higher activity and selectivity in benzene hydrogenation reaction, the same catalyst prepared by the colloidal method demonstrated lower selectivity.
Carbon nanomaterials for supercapacitors: two electrode scheme
Authors: Popov Maxim V. , Bannov Alexander G. , Yusin Stepan I.
Published: July 2021

In this paper, the electrochemical and texture characteristics of electrode materials made of a number of promising carbon materials for supercapacitors were considered. Carbon nanofibers, thermally expanded graphite, and activated carbon derived from rice hulls were used as electrodes for supercapacitors. The paper presents a technique of synthesis of these electrode materials. A comparison of the capacitive characteristics of the electrodes using two-electrode scheme was carried out.
Catalytic processing of distillate fractions of a resin in the presence of finely dispersed catalysts
Authors: Smagulova Nazym , Kairbekov Zhaxyntay , Ussenov Nurlan
Published: July 2021

The article describes the catalytic cracking of heavy oil residue in the presence of a finely dispersed catalyst. It was determined that in the processing of high molecular weight hydrocarbons, catalysts are effective, which are uniformly distributed in the volume of raw materials and are introduced into the technological process in the form of small particles. Coke tar mainly consists of 27.00 wt.% asphaltenes, 60.00 wt.% of polyaromatic hydrocarbons that have been studied and identified as a potential source of raw materials to produce motor fuels in the future.
Synthesis and electrical properties of Ag16I12P2O7
Authors: Ulihin Artem , Protazanova Olga
Published: July 2021

Superionic solid electrolyte Ag16I12P2O7 was prepared using solid state synthesis. The ionic conductivity of this compound was studied by the complex impedance spectroscopy method in a wide temperature range. It is shown that Ag16I12P2O7 is characterized by a high ionic conductivity at room temperature, comparable to the conductivity of liquid electrolytes.
Ist die post-pandemische Zukunft offline?
Authors: Mehnert-Theuerkauf Anja
Published: July 2021

Ist die post-pandemische Zukunft offline? Natürlich nicht! Diese Frage werden
die meisten wohl zu Recht verneinen. Im Gegenteil: Durch die Einschränkungen
der Sozialkontakte bedingt durch die COVID-19-Pandemie hat unser virtuelles Leben
deutlich Aufwind bekommen, tatsächlich vieles erleichtert und nicht zuletzt
zu einer höheren digitalen Kompetenz im Umgang mit verschiedenen virtuellen
Formaten beigetragen. Videokonferenzen mit Kooperationspartnern, Videosprechstunden
mit Patienten und Videochats mit Kollegen bestimmen mittlerweile unseren Alltag.
Durch den Boom von Webinaren und Online-Konferenzen können viele Menschen
ihren Job komplett zu Hause erledigen. Unsere Arbeitswelt scheint flexibler geworden
zu sein – und das Internet noch lebenswichtiger, als es vor Beginn der
Pandemie bereits war.
Predictive Ability of a Clinical-Genetic Risk Score for Venous Thromboembolism in Northern and Southern European Populations
Authors: Salas Eduardo , Farm Maria , Pich Sara , Onelöv Liselotte , Guillen Kevin , Ortega Israel , Antovic Jovan P. , Soria Jose Manuel
Published: July 2021

Venous thromboembolism (VTE) is a complex, multifactorial problem, the development of which depends on a combination of genetic and acqfiguired risk factors. In a Spanish population, the Thrombo inCode score (or TiC score), which combines clinical and genetic risk components, was recently proven better at determining the risk of VTE than the commonly used model involving the analysis of two genetic variants associated with thrombophilia: the Factor V Leiden (F5 rs6025) and the G20210A prothrombin (F2 rs1799963).

The aim of the present case–control study was to validate the VTE risk predictive capacity of the TiC score in a Northern European population (from Sweden).

The study included 173 subjects with VTE and 196 controls. All were analyzed for the genetic risk variants included in the TiC gene panel. Standard measures —receiver operating characteristic (ROC) area under the curve (AUC), sensitivity, specificity, and odds ratio (OR)—were calculated.

The TiC score returned an AUC value of 0.673, a sensitivity of 72.25%, a specificity of 60.62%, and an OR of 4.11. These AUC, sensitivity, and OR values are all greater than those associated with the currently used combination of genetic variants. A TiC version adjusted for the allelic frequencies of the Swedish population significantly improved its AUC value (0.783).

In summary, the TiC score returned more reliable risk estimates for the studied Northern European population than did the analysis of the Factor V Leiden and the G20210A genetic variations in combination. Thus, the TiC score can be reliably used with European populations, despite differences in allelic frequencies.
Chudley–McCullough Syndrome: Case Report and the Role of Neuroimaging to Suggest the Diagnosis
Authors: Freitas Leonardo Furtado , Barros Gabriel Santaterra , Barletta Enrico Affonso , de Araújo Coimbra Pablo Picasso , Lourenço Charles Marques , Ferreira Paula Mendes
Published: July 2021

Chudley–McCullough syndrome (CMS) is an autosomal recessive condition first described in 1997. The most striking features of this syndrome include sensorineural hearing loss, craniofacial disproportion, and brain abnormalities such as agenesis of the corpus callosum, polymicrogyria, ventriculomegaly, and changes in cerebellar architecture. We described the case of a 2-year-old male child patient with CMS confirmed by genetic testing (GPSM2 gene mutation), who presented with global developmental delays and characteristic neuroimaging features including arachnoid cysts, agenesis of the corpus callosum, cerebellar dysplasia, and frontal heterotopia. Early recognition of this rare clinical syndrome may reduce the diagnostic odyssey and ultimately improve the quality of life for affected children. This report will focus on unique clinical and radiographic features of CMS.
Steroids Significantly Decrease Postoperative Postural Hypotension in Total Knee Replacement
Authors: Cheng Gloria H. M. , Tan Gabriel K. Y. , Kamarudin Muhammad F. B. , Lee Bryan W. W. , Mei Yap Yan , Tan Kelvin G.
Published: July 2021

Total knee replacement (TKR) is one of the most common orthopaedic procedures performed, and enhanced recovery after surgery (ERAS) has been developed and incorporated into inpatient surgical pathways to improve patient outcomes. Under ERAS recommendations, multimodal prophylaxis has been used to help manage postoperative nausea and vomiting (PONV) following TKR. Dexamethasone is one of the commonly used for this and the anti-inflammatory properties could depress vagal activity, reducing postural hypotension (PH). The hypothesis of this study is that postoperative dexamethasone use is associated with lower rates of early postoperative PH following TKR surgery. In our institution, patients who undergo elective primary TKR are admitted on the day of surgery and follow a standardized ERAS protocol. Data on patients who underwent elective primary TKR under a single adult reconstruction team from September 2017 to March 2020 were reviewed and analyzed. A review of demographic characteristics, surgical data, postoperative medications, and postoperative notes was performed. Binary logistic regression was used to assess the effect of the use of dexamethasone on PH, with an adjusted odds ratio (OR) calculated after accounting for potential confounders. Of the 149 patients were included in the study, 78 had dexamethasone postoperatively, and 71 did not. Patients who had received dexamethasone were statistically less likely to suffer from PH (OR = 0.31, p = 0.03) and less likely to develop PONV (OR = 0.21, p = 0.006). Patients who had received dexamethasone were more likely able to participate in early physiotherapy (OR = 2.42, p = 0.14), and this result was statistically insignificant. The use of postoperative intravenous dexamethasone is significantly associated with lower rates of postoperative PH after TKR. However, more studies are required to assess the optimal dosing amount and frequency, as well as to assess other factors which can enhance early postoperative patient mobilization as part of our goals for ERAS. This therapeutic study reflects level of evidence III.
Exploiting random magnetic phenomena for computational applications
Authors: Bandari Anashe
Published: July 2021

A perspective presents the challenges and prospects of taking advantage of these typically unwanted effects for data security, probabilistic computing and neuromorphic computing.
Algebraic approach and Berry phase of a Hamiltonian with a general SU
(1, 1) symmetry
Authors: Choreño E. , Valencia R. , Ojeda-Guillén D.
Published: July 2021

In this paper, we study a general Hamiltonian with a linear structure given in terms of two different realizations of the SU(1, 1) group. We diagonalize this Hamiltonian by using the similarity transformations of the SU(1, 1) and SU(2) displacement operators performed to the su(1, 1) Lie algebra generators. Then, we compute the Berry phase of a general time-dependent Hamiltonian with this general SU(1, 1) linear structure.
Bistability bifurcation phenomenon induced by non-Newtonian fluids rheology and thermosolutal convection in Rayleigh–Bénard convection
Authors: Rebhi Redha , Mamou Mahmoud , Hadidi Noureddine
Published: July 2021

In the present paper, a numerical investigation was performed to assess the effect of the rheological behavior of non-Newtonian fluids on Rayleigh–Bénard thermosolutal convection instabilities within shallow and finite aspect ratio enclosures. Neumann and Dirichlet thermal and solutal boundary condition types were applied on the horizontal walls of the enclosure. Using the Boussinesq approximation, the momentum, energy, and species transport equations were numerically solved using a finite difference method. Performing a nonlinear asymptotic analysis, a bistability convective phenomenon was discovered, which was induced by the combined fluid shear-thinning and aiding thermosolutal convection effects. Therefore, bistability convection was the main focus in the current study using the more practical constitutive Carreau–Yasuda viscosity model, which is valid from zero to infinite shear rates. Also, the combined effects of the rheology parameters and double diffusive bistability convection were studied. For aiding flow, the shear-thinning and the slower diffusing solute effects were counteracting and, as a result, two steady-state finite amplitude solutions were found to exist for the same values of the governing parameters, which indicated and demonstrated evidence for the existence of bistability convective flows. For opposing flows, the shear-thinning effect strengthened subcritical flows, which sustained well below the threshold of Newtonian thermosolutal convection. Thus, bistability convection did not exist for opposing flows, as both the shear-thinning and the slower diffusing component effects favored subcritical convection.
Experimental and numerical evidence of intensified non-linearity at the microscale: The lipid coated acoustic bubble
Authors: Sojahrood A. J. , Haghi H. , Porter T. M. , Karshafian R. , Kolios M. C.
Published: July 2021

A lipid coated bubble (LCB) oscillator is a very interesting non-smooth oscillator with many important applications ranging from industry and chemistry to medicine. However, due to the complex behavior of the coating intermixed with the nonlinear behavior of the bubble itself, the dynamics of the LCB are not well understood. In this work, lipid coated Definity® microbubbles (MBs) were sonicated with 25 MHz 30 cycle pulses with pressure amplitudes between 70 and 300 kPa. Here, we report higher order subharmonics in the scattered signals of single MBs at low-amplitude high-frequency ultrasound excitations. Experimental observations reveal the generation of period 2, period 3, and two different period 4 oscillations at low excitation amplitudes. Despite the reduced damping of the uncoated bubble system, such enhanced nonlinear oscillations have not been observed and cannot be theoretically explained for the uncoated bubble. To investigate the mechanism of the enhanced non-linearity, the bifurcation structure of the lipid coated MBs is studied for a wide range of MBs sizes and shell parameters. Consistent with the experimental results, we show that this unique oscillator can exhibit chaotic oscillations and higher order subharmonics at excitation amplitudes considerably below those predicted by the uncoated oscillator. Buckling or rupture of the shell and the dynamic variation of the shell elasticity cause the intensified non-linearity at low excitation pressure amplitudes. The simulated scattered pressure by single MBs is in good agreement with the experimental signals.