bluuebunny/crossref_metadata_2025 huggingface dataset:
Extrinsic and intrinsic factors influencing the emergence and return of the Asian particolored batVespertilio sinensisto the summer roost
Authors: Feng Lei , Qin Hexuan , Li Jingjing , Li Xin , Feng Jiang , Jiang Tinglei
Published: May 2022

Circadian rhythms play a crucial role in the health and survival of organisms. However, little is known concerning how intrinsic and extrinsic factors affect animal daily rhythms in the field, especially in nocturnal animals. Here, we investigated the first emergence, mid‐emergence, and return times ofVespertilio sinensis, and also integrated environmental conditions (temperature, humidity, and light intensity) and biotic factors (reproductive status and predation risk) to determine causes of variation in the activity rhythms of the bats. We found that variation in the first emergence time, the mid‐emergence time, and the final return time were distinct. The results demonstrated that the emergence and return times of bats were affected by light intensity, reproductive status, and predation risk in a relatively complex pattern. Light intensity had the greatest contribution to activity rhythms. Moreover, we first investigated the effects of actual predators on the activity rhythms of bats; the results showed that the mid‐emergence time of bats was earlier as predators were hunting, but the final return time was later when predators were present. Finally, our results also highlighted the importance of higher energy demands during the lactation in bats to variation in activity rhythms. These results improve our understanding of the patterns and causes of variation in activity rhythms in bats and other nocturnal animals.
Measuring plant biomass remotely using drones in arid landscapes
Authors: McCann Justin A. , Keith David A. , Kingsford Richard T.
Published: May 2022

Measurement of variation in plant biomass is essential for answering many ecological and evolutionary questions. Quantitative estimates require plant destruction for laboratory analyses, while field studies use allometric approaches based on simple measurement of plant dimensions.

We estimated the biomass of individual shrub‐sized plants, using a low‐cost unmanned aerial system (drone), enabling rapid data collection and non‐destructive sampling. We compared volume measurement (a surrogate for biomass) and sampling time, from the simple dimension measurements and drone, to accurate laboratory‐derived biomass weights. We focused on three Australian plant species which are ecologically important to their terrestrial and floodplain ecosystems: porcupine grass Triodia scariosa, Queensland bluebush Chenopodium auricomum, and lignum Duma florulenta.

Estimated volume from the drone was more accurate than simple dimension measurements for porcupine grass and Queensland bluebush, compared to estimates from laboratory analyses but, not for lignum. The latter had a sparse canopy, with thin branches, few vestigial leaves and a similar color to the ground. Data collection and analysis consistently required more time for the drone method than the simple dimension measurements, but this would improve with automation.

The drone method promises considerable potential for some plant species, allowing data to be collected over large spatial scales and, in time series, increasing opportunities to answer complex ecological and evolutionary questions and monitor the state of ecosystems and plant populations.
Dammed water quality—Longitudinal stream responses below beaver ponds in the Umpqua River Basin, Oregon
Authors: Stevenson John R. , Dunham Jason B. , Wondzell Steven M. , Taylor Jimmy
Published: May 2022

Beaver‐related restoration (BRR) has gained popularity as a means of improving stream ecosystems, but the effects are not fully understood. Studies of dissolved oxygen (DO) and water temperature, key water quality metrics for salmonids, have demonstrated improved conditions in some cases, but warming and decreased DO have been more commonly reported in meta‐analyses. These results point to the contingencies that can influence outcomes from BRR. We examined water quality related to beaver ponds in a diverse coastal watershed (Umpqua River Basin, OR, USA). We monitored water temperature 0–400 m above and below beaver ponds and at pond surfaces and bottoms across seven study sites from June through September of 2019. DO was also recorded at two sites at pond surfaces and pond bottoms. Downstream monthly mean daily maximum temperatures were warmer than upstream reference locations by up to 1.9°C at beaver dam outlets but this heating signal attenuated with downstream distance. Downstream warming was greatest in June and July and best predicted by pond bottom temperatures. DO at pond surfaces and bottoms were hypoxic (≤5 mg/L) for more than half of the 32‐day monitoring period. Water temperatures increased for short distances below monitored beaver ponds and observed oxygen conditions within ponds were largely unsuitable for salmonid fishes. These findings contrast with some commonly stated expectations of BRR, and we recommend that managers consider these expectations prior to implementation. In some cases, project goals may override water quality concerns but in streams where temperature or DO restoration are objectives, managers may consider using BRR techniques with caution.
Removal of Phthalates from Water by Unconventional La‐based/WO3 Photocatalysts
Authors: Malannata Enrica Maria , Spitaleri Luca , Gulino Antonino , Balsamo Stefano Andrea , Scirè Salvatore , Fiorenza Roberto
Published: May 2022

La2O2CO3‐WO3 composites were here proposed as unconventional photocatalysts for the removal of phthalates in water. The high sorption properties of the lanthanum dioxide carbonate allowed a strong adsorption of the phthalates which facilitated the following solar photocatalytic degradation, further boosted by the addition of small amounts of WO3 (1 wt%). On the contrary, a higher content of WO3 had a detrimental effect due to the covering of the surface sites of La2O2CO3 that inhibited the adsorption process. This double mechanism of strong adsorption‐photocatalytic oxidation led, after 6 h of solar irradiation, to 67 % and 63 % dimethyl phthalate and di(2‐ethylhexyl)phthalate degradation, respectively. The phthalates were degraded to less persistent pollutants that, however, were completely removed after 9 h of irradiation. The La2O2CO3‐WO3 system appears promising for its application in the removal of the emerging contaminants from water.
Superoxide Reduction by Cu‐Amyloid Beta Peptide Complexes: A Density Functional Theory Study
Authors: Arrigoni Federica , Di Carlo Chiara , Rovetta Alberto , De Gioia Luca , Zampella Giuseppe , Bertini Luca
Published: May 2022

Oxidative stress and copper dyshomeostasis are well established factors in the course of Alzheimer's disease (AD). Indeed, the pathological interaction of copper with the amyloid peptide is able to induce reactive oxygen species (ROS) production through a three‐step cycle in which O2is gradually reduced to superoxide, oxygen peroxide and finally to highly neurotoxic OH⋅ radicals. The purpose of this study has been to investigate at a computational level, by Density Functional Theory (DFT) and molecular mechanics techniques, the final two steps of O2reduction to OH−+OH radical i.e the superoxide and hydroperoxide reduction by ascorbate, on different Cu(II) ⋅ Aβ coordination models. At variance with the first step of O2reduction to O2.−characterized by high energy barrier, the successive O2.−and O2H−reductions are low energy barriers processes and that the OH⋅ radical formation is further favored by the possibility of Cu(II) ⋅ Aβ to form the Asp1 amino terminal radical. We discuss the results obtained from the perspective of the recent findings in the Aβ redox chemistry in AD pathology.
Growth Performance, Carcass Traits, Muscle Fatty Acids, Intramuscular Fat, Cholesterol, and Antioxidant Status in Rabbits Supplemented with Kigelia pinnata Leaf Meal
Authors: Adeyemi Kazeem D. , Akinfenwa Oladayo A. , Atolani Olubunmi , Shittu Rafiat M. , Adeyina Adebisi O. , Aliyu Karimat I.
Published: May 2022

The effects of dietary Kigelia pinnata leaf (KPL) on growth, carcass, muscle fatty acids, antioxidant status, cholesterol, physicochemical properties, and sensory profile of Longissimus thoracis et lumburum (LTL) muscle in rabbits are investigated. Seventy‐two, 32 d old male New Zealand rabbits (684 ± 18 g) are randomly assigned to diets containing either no KPL (KPL‐0), 5% KPL (KPL‐5) or 10% KPL (KPL‐10) for eight weeks, and euthanized, and the LTL is refrigerated for 6 days. Dietary KPL does not influence growth performance and carcass cuts in rabbits. Abdominal fat is lower in KPL‐ rabbits than in the KPL‐0 rabbits. Supplemented LTL has lower intramuscular fat and cholesterol, and higher crude protein, polyphenol content, glutathione reductase, and catalase compared with the control LTL. Concentration of C18:3n‐3, C22:6n‐3, and C20:5n‐3 is higher in supplemented LTL than the control LTL. Supplemented meat has lower cook loss than the KPL‐0 meat at 24 h postmortem. The KPL‐10 meat has higher redness and lower malondialdehyde content than other meats on d 6 postmortem. Juiciness and overall acceptance of the supplemented meat are higher than that of the KPL‐0 meat. Supplementation with KPL‐10 enhances muscle n‐3 fatty acids, sensorial quality, and oxidative stability of rabbit meat.

Practical Applications: Practical applications: Rabbit meat is replete in n‐6 polyunsaturated fatty acid (PUFA) but low in n‐3 PUFA, which heightens its n‐6/n‐3 ratio. Higher n‐6/n‐3 PUFA intake can pose serious health risks to consumers. This suggests a need to ameliorate the n‐3 PUFA of rabbit meat. Dietary KPL causes ≈147–184% increase in n‐3 PUFA and a 66–77% decrease in n‐6/n‐3 ratio in rabbit meat. Moreover, KPL improves sensorial quality and oxidative stability and lowers intramuscular fat and cholesterol content of rabbit meat. These results support the delivery of a healthier rabbit meat that responds to consumer demands. This study explicates the potential of KPL in ameliorating the nutritional value and sensory quality of rabbit meat.
Preparation of Highly Stable Z‐Isomer‐Rich Lycopene Nanodispersions via a Continuous‐Flow System with Selected Emulsifiers
Authors: Murakami Kazuya , Kageyama Hakuto , Hibino Takashi , Zhang Yelin , Goto Motonobu , Honda Masaki
Published: May 2022

As a potent antioxidant with numerous health benefits, lycopene finds multiple applications. Among the geometric isomers of lycopene, the Z‐isomers have greater bioavailability than the all‐E‐isomer but are less stable and hence, less suitable for practical applications. Herein, highly stable Z‐isomer‐rich lycopene nanodispersions are produced through the thermal isomerization of (all‐E)‐lycopene in a flow reactor followed by continuous dispersion in an aqueous emulsifier (Tween 20, sucrose fatty acid ester, or polyglycerol fatty acid ester [PFAE]) solution upon agitation with an in‐line swirl mixer. The effects of emulsifier type and other processing conditions (flow rate, pressure, temperature, lycopene Z‐isomer ratio) on dispersion efficiency and properties are examined in detail, and finally, Z‐isomer‐rich lycopene nanodispersions (>60% of total Z‐isomer ratio and <10 nm of mean particle size) are successfully obtained. Moreover, it is found that lycopene Z‐isomers have greater encapsulation efficiency for dispersions with emulsifiers than that of the all‐E‐isomer. The storage test of the resulting dispersions clearly shows that the highest storage stability is achieved in the case of using PFAE, which effectively inhibits lycopene degradation and reverse (Z‐ to all‐E) isomerization.

Practical applications: To practical use of lycopene Z‐isomers, it is essential to improve their storage stability as well as usability (i.e., dispersibility in water). The present study reveals that when producing the lycopene dispersions, the use of PFAE as an emulsifier allows to improve the stability of lycopene isomers and inhibit the Z‐ to all‐E‐isomerization during storage. Given the high demand for stable Z‐isomer‐rich lycopene formulations, the obtained results promote the practical use of lycopene Z‐isomers in diverse (e.g., food and cosmetic) industries.
Nickel‐Catalysed Amination of Arenes and Heteroarenes
Authors: Philip Rose Mary , Veetil Saranya Padinjare , Anilkumar Gopinathan
Published: May 2022

C(sp2)−N cross‐coupling is one of the most powerful transformations in organic synthesis to construct highly ubiquitous anilines and aniline derivatives. The dominance of Pd‐ and Cu‐based catalytic systems is evident in the field for a long time. However, Ni‐catalysed methodologies to achieve this reaction have grown gradually as sustainable alternatives in the last two decades. Recent reports of highly applicable photocatalytic and electrochemical amination strategies sufficiently enhanced the potential of Ni‐catalysed aminations. This review summarizes the advancement of this cross‐coupling reaction as a general and efficient method over the last 5 years.
Catalyst‐ and Metal‐Free Photo‐Oxidative Coupling of Thiols with BrCCl3
Authors: Li Xiaoman , Fan Jiali , Cui Dezhi , Yan Hui , Shan Shiquan , Lu Yongna , Cheng Xiamin , Loh Teck‐Peng
Published: May 2022

This paper reported a catalyst‐ and metal‐free method to construct disulfide bond with BrCCl3 under light irradiation. This clean and mild reaction promoted the oxidative coupling of thiols with wide substrate scope, and is applicable to benzylic, aryl and aliphatic thiols, especially cysteine derivative. The disulfides were obtained in high yields up to 98 %, avoiding the use of heating, strong oxidant, metal reagent or catalyst. This facile strategy will facilitate the synthesis of disulfide compounds.
Sensor Modified with Gold Nanoparticles Stabilized in Dialdehyde Starch/DMSO Matrix for Methyldopa Detection
Authors: Alves Freitas Aline , Cruz Vieira Iolanda
Published: May 2022

In this study, gold nanoparticles (AuNP) were synthesized using a novel stabilizer based on dialdehyde starch polymer (DAS) and dimethyl sulfoxide (DMSO) and the nanomaterial was applied to develop a sensor for methyldopa detection. The nanoparticles were characterized by transmission electron microscopy and the proposed sensor was electrochemically characterized by electrochemical impedance spectroscopy, chronocoulometry and square‐wave voltammetry. Under optimized conditions (0.1 mol L−1 McIlvaine buffer solution at pH 3.5 and 50 μL AuNP/DAS‐DMSO), using square‐wave voltammetry, the calibration curve presented a linear range of 0.99 to 19.60 μmol L−1, with a detection limit of 0.50 μmol L−1. The sensor showed good accuracy, with coefficients of variation of 7.8 % (inter‐day; n=6) and 5.9 % (intra‐day; n=3), and recovery values in the range of 95.3 to 105.2 %. The methyldopa content in a pharmaceutical sample was determined and the results show good correlation with the label value and the method recommended by the Pharmacopoeia, representing a fast and accurate alternative for detecting methyldopa in pharmaceutical products.
β‐Cyclodextrin PAMAM Dendrimer Surface Doped with Silver and Hexacyanoferrate (III) and its Applications for Dopamine Detection in Synthetic Samples
Authors: Pereira Barbosa Priscila Fernanda , Mastelaro Valmor Roberto , Guimarães Vieira Eduardo , Ribeiro do Carmo Devaney
Published: May 2022

A synthesis of β‐cyclodextrin (β‐Cd) functionalized with polyamide dendrimer PAMAM G.0 complexed with silver and potassium hexacyanoferrate (III) forming a mixed‐valence complex (β‐Cd‐PAMAM‐Ag/Fe) was proposed. This material was characterized by scanning electron microscopy (SEM), infrared spectroscopy (FT‐IR), X‐Ray diffraction (XRD), Energy Dispersion Spectroscopy (EDS) and Electron Paramagnetic Resonance (EPR). The hybrid complex was electrochemically investigated using cyclic voltammetry and some parameters (electrolyte, concentration of electrolyte, pH and scan rate) were evaluate in order to obtain optimum analytical responses. The β‐Cd‐PAMAM‐Ag/Fe material was successfully applied in the electrocatalytic oxidation of dopamine (DOP) using Cyclic Voltammetry (CV) and Square Wave Voltammetry (SWV).
Optimization of energy ratio, benefit to cost and greenhouses gasses using metaheuristic techniques (genetic and particular swarm algorithms) and data envelopment analysis: Recommendations for mitigation of inputs consumption (a case crop: edible onion)
Authors: Elhami Behzad , Raeini Mahmoud Ghasemi Nejad , Taki Morteza , Marzban Afshin , Heidarisoltanabadi Mohsen
Published: May 2022

The present study aimed to optimize the energy, economic, and greenhouse effects indices for edible onion production in Fereydan (85 growers), and Buin (15 growers) regions in Isfahan. Required data were collected through direct measurement, interview, and questionnaire. Total energy input was obtained before and after optimization using data envelopment analysis (DEA), multi‐objective genetic algorithm (MOGA), and multi‐objective particle swarm algorithm (MOPSA), and was determined as 236,335, 213,068 (8.75% saving), 125,663 (48.63% saving), and 320,657 MJ ha−1(35.67%), respectively. In addition, energy ratio (ER) was improved from 0.79 to 0.84, 1.81, and 0.8 using DEA, MOGA, and MOPSA, respectively. By reducing the production costs by 10.2%, 63.12%, and 29.4% using DEA, MOGA, and MOPSA, respectively, benefit‐to‐cost ratio (BCR) index was improved from 1.44 to 1.88, 5.21, and 1.94, respectively. Also results showed that GHG emissions were mitigated by 18.39%, 47.56%, and 27.94%, respectively. Based on the findings, MOGA showed better performance compared to DEA, and MOPSA in terms of ER, BCR, and GHG factors. Despite applying metaheuristic, and artificial intelligence methods by MOPSA, this algorithm was not able to optimize the target factors, and applied the energy, and production costs in negative status (in reverse).
Sol‐gel based copper metallic layer as external anode for microtubular solid oxide fuel cell
Authors: Shabri Hazrul Adzfar , Rudin Siti Norlaila Faeizah Mohd , Othman Mohd Hafiz Dzarfan , Jamil Siti Munira , Kamal Siti Nur Elida Aqmar Mohd , Abu Bakar Suriani , Osman Nafisah , Jaafar Juhana , Rahman Mukhlis A , Ismail Ahmad Fauzi
Published: May 2022

Solid oxide fuel cell (SOFC) performance depends greatly on the anode conductivity, which in traditional nickel‐yttria stabilized zirconia (Ni‐YSZ) anode is determined by the Ni content that is infamous for its coking problem under hydrocarbon fuel. Without the use of high content of Ni, anode conductivity can be elevated by adding an external metal layer on top of the anode. In this study, we present the incorporation of copper (Cu) metal layer on top of the anode of micro‐tubular SOFC by applying a modified sol‐gel method using syringe deposition technique at various chemical compositions and deposition cycles. Cu sol was found best to be made up of 2:1:8 ratio of Cu: citric acid: ethylene glycol, with 1.36 μm metal layer formed at 5 deposition cycle, and no obvious increase in thickness after the fifth cycle. The Cu layer elevated the conductivity by 1010 times compared to the uncoated anode. However, the coated layer also reduced the gas permeability by 10 times in the anode, which resulted from the blocking of a nano‐sized pore in the anode, rather than the micron size pore. This blocking can be resolved by increasing the amount of micron‐sized pore by using pore former during anode fabrication. From electrochemical impedance spectroscopy (EIS), Cu coating reduced the ohmic resistance (Rohm) and charge transfer resistance (Rct). From the current‐voltage curve, the maximum power density (MPD) was found to increase linearly with the increase of the Cu coating cycle, but the value is almost stagnant at 2.3 to 2.5 mW cm−2 when the coating cycle of more than 4 was employed. This suggests that anode gas permeation plays an important role in anode conductivity. The findings from this study suggested that 5 deposition cycle shows to be the optimal coating layer required to achieve the percolation threshold without unnecessary loss in permeability.
Constructing micropore‐rich nitrogen‐doped carbon for high‐performance supercapacitor and adsorption of carbon dioxide
Authors: Sahu Priya , Mishra Ranjit , Panigrahy Sonali , Panda Prajnashree , Barman Sudip
Published: May 2022

Design of advanced highly porous heteroatom‐doped carbon is desirable for their wide presence in applications like electrochemical energy storage systems, gas adsorption, and separation processes. In this work, porous nitrogen‐doped carbon was developed from ethylenediamine via an in situ self‐doping solvothermal process followed by pyrolysis and KOH activation under high temperature. Micropore‐rich nitrogen‐containing carbon materials were prepared through variation of the KOH/C ratio during activation and their electrochemical performance in alkaline electrolyte as well as CO2 sorption behaviour was evaluated. The porous carbon developed using KOH/C ratio of 2 delivered highest supercapacitor performance in 6 M KOH achieving high specific capacitance of 353 F g−1 with 1 A g−1 of current due to its high pore volume and micropore rich surface. The functionalized carbon delivered CO2 uptake capacities of 4.48 and 3.0 mmol g−1 under temperatures of 273 and 298 K, respectively, at 1 bar pressure with a good CO2/N2 selectivity of 20.58 and CO2/CH4 selectivity of 3.83. The existence of nitrogen functional groups, high surface area, and micropore‐rich porous structures may be the essential reasons behind superior electrode performance and CO2 capture capacity of the material. This work hopefully offers a simple development of N‐doped carbon for effective energy storage and CO2 adsorption systems.
Improved platinum‐nickel nanoparticles with dopamine‐derived carbon shells for proton exchange membrane fuel cells
Authors: Jang Injoon , Lee Sehyun , Jang Jue‐Hyuk , Ahn Minjeh , Yoo Sung Jong
Published: May 2022

Using platinum‐based alloy nanocatalysts with other transition metals has the advantages of enhancing the oxygen reduction reaction (ORR) activity and reducing the platinum usage. However, there are many challenges to using nanocatalysts, including their instability, which hinder their practical application. In this study, we employed a strategy to improve the intrinsic instability of a nanocatalyst by encapsulating a dopamine‐derived carbon layer on the surfaces of nanoparticles. The carbon layer formed on the surfaces of platinum‐nickel (PtNi) nanoparticles demonstrated improved stability by inhibiting the nanoparticle growth, even during the heat treatment process. This could induce a high degree of alloying while minimizing the loss of surface area for the nanoparticles, which ensured an improved catalyst activity. Additionally, the PtNi nanocatalyst with the dopamine‐derived carbon layer showed an improved performance and stability under long‐term fuel cell operation conditions, thus proving the practicality of this strategy. The strategy developed in this study is not only a novel and facile approach to the synthesis of alloy catalysts, but also addresses the inherent instability of nanoparticles, which will encourage the practical use and commercialization of alloy nanocatalysts.
Enhanced performance by heteroatom‐doped reduced graphene oxide‐TiO2‐based nanocomposites as photoanodes in dye‐sensitised solar cells
Authors: Ngidi Nonjabulo P. D. , Muchuweni Edigar , Nyamori Vincent O.
Published: May 2022

The photoanode in a dye‐sensitised solar cell (DSSC) plays a crucial role in achieving a high power conversion efficiency (PCE). It supports the sensitiser and acts as a transporter of photo‐excited electrons from the sensitiser to the external circuit. These two functions are enhanced by a large surface area and a fast charge transport rate. Typically, the photoanode consists of titanium dioxide (TiO2) nanoparticles. If the nanoparticles are deposited on a carbonaceous substrate, it facilitates the transport of photogenerated electrons. This study compared the photoanode performance of boron‐ or nitrogen‐doped reduced graphene oxide (B‐ or N‐rGO) nanocomposites integrated with TiO2. All nanocomposites exhibited mainly the anatase TiO2 phase, and N‐rGO‐TiO2 exhibited the lowest bandgap of 2.1 eV, which was attributed to the formation of Ti‐O‐C and Ti‐O‐N bonds. Also, N‐rGO‐TiO2 displayed good charge carrier separation ability and electron transfer. The low TiO2 content in the nanocomposites led to the suppression of electron‐hole recombination, reduction in the bandgap energy and improvement in electron transport, resulting in higher current density. Two photo‐harvesting dyes (sensitisers) were investigated, that is, eosin B and Sudan II. A higher light‐harvesting efficiency was obtained from eosin B, indicating the presence of more dye molecules anchored onto the TiO2. Photoanodes fabricated from N‐rGO‐TiO2 and B‐rGO‐TiO2 showed enhanced photo‐exciton generation, higher short‐circuit current densities and significantly better PCEs of 3.94% and 2.55%, respectively, than their undoped rGO‐TiO2 counterparts (1.78%). This work demonstrates that heteroatom‐doped rGO‐TiO2‐based nanocomposites can improve the rate of transportation and collection of electrons, thereby enhancing the performance of DSSCs.
Trash to treasure: Fallen leaves as separators for supercapacitors
Authors: Chen Shaoqin , Hu Yun H.
Published: May 2022

Electrochemical double‐layer capacitors are an essential type of energy‐storage devices due to their fast charge/discharge rate, ultralong cycle life, and safe operation. A separator plays an important role in supercapacitors to prevent short circuit while allow ions to move through its porous structure. Herein, we demonstrated fallen leaves as efficient separators in supercapacitors with dense mesoporous carbon electrodes, achieving a high areal capacitance of 1.94 F/cm2. Among four leaves, Quercus rubra leaf exhibited the best electrochemical performance as a separator for supercapacitors, which is even comparable to the commercial glass fiber separator. This finding provides an approach not only to transfer waste into treasure but also to develop sustainable separators for energy‐storage devices.
Review and direct evidence of transgressive aeolian sand sheet and dunefield initiation
Authors: Hesp Patrick A. , DaSilva Marcio , Miot da Silva Graziela , Bruce David , Keane Robert
Published: May 2022

The multiple hypotheses which exist to explain the initiation of transgressive aeolian sand sheets and dunefields, are reviewed and discussed. Direct evidence supporting many of these hypotheses is largely lacking. In South Australia, the Younghusband Peninsula coastal barrier extends ~180 km and predominantly comprises transgressive and parabolic dunefields. The 42 Mile Crossing area on the barrier is undergoing significant erosion at variable rates of 0.5 to 5.0 m/yr, and a new transgressive aeolian sand sheet has rapidly developed in ~1 year and is extending landwards at an average rate of 13 m/yr. This research provides unequivocal evidence that large‐scale shoreline and dunefield erosion does lead to the development of a new transgressive aeolian sand sheet (and eventual dunefield) phase thereby demonstrating an initiation mechanism that is likely linked to future sea level rise and climate change. We also show that the initiation process, and, in particular, the subsequent rate of sand sheet transgression occurs at an incredibly rapid rate (+100 m in 8 years).

Plain Language Summary

Coastal sand dunes border many of the world's coastlines and are highly adapted to local climate and conditions. How coastal dunes transition from predominantly vegetated and stable systems to wind‐blown sand sheets and dunefields transgressing prior terrain is a research area of pressing relevance due to forecasts of sea level rise and climate change. The factors or triggers that are considered to initiate transgressive aeolian sand sheets and dunefields are reviewed. The formation and evolution of a new transgressive aeolian sand sheet phase triggered by large‐scale shoreline erosion in South Australia is presented. According to the results from historical and satellite images, local shoreline erosion began in the late 1970s and has continued at highly variable rates. We show that once the foredune was removed, the high scarp created by wave erosion of the relict, vegetated transgressive dunefield destabilized and was then eroded by wind processes leading to the rapid development of a transgressive aeolian sand sheet. The initiation and evolution of the sand sheet provides an excellent example of how dunefields might respond to future sea level rise and climate change.
Determinants and dynamics of blowouts in Hulun Buir sandy grassland, Inner Mongolia, China from 1959 to 2018
Authors: Guan Chao , Hasi Eerdun , Yang Yi , Sun Yu , Du Huishi
Published: May 2022

The formation and development of blowouts is an important surface indication of sand drift activity in the Hulun Buir sandy grassland and the main cause of landscape pattern heterogeneity. In this study, dynamic changes and determinants of blowouts in this region were studied via analysis of multi‐period high‐resolution remote sensing data from 1959 to 2018. The different stages of activity and dominant factors of the fixation and activation of blowouts were analysed with Lancaster's M‐index. The results show that the activity of blowouts in Hulun Buir sandy grassland can be divided into three stages from 1959 to 2018: (I) growth and expansion stage, from 1959 to 2004; (II) fixation and grassland recovery stage, from 2005 to 2010; (III) redevelopment stage, from 2011 to 2018. The two geomorphic units of depressions and depositional lobes exhibit different responses to changes in climatic factors. The depositional lobes are more sensitive to the change in external factors with better feedback and their areas and numbers change with the variation of stage, while depressions exhibit relatively slow changes. The wind regime is the dominant factor explaining the variation of activity of blowouts, with precipitation and potential evapotranspiration as secondary factors for this region. Roads have little effect on the development and deformation of blowouts, but the movement of cattle and sheep across the region has a big influence. Therefore, the desertification process of Hulun Buir grassland is driven by both natural and human factors.
Review on energy storage in lead‐free ferroelectric films
Authors: Puli Venkata Sreenivas , Jayakrishnan AR , Pradhan Dhiren Kumar , Madgula Kalpana , Babu S. Narendra , Chrisey Douglas B. , Katiyar Ram S. , Reed Amber , McConney Michael , Back Tyson , Van Ginhoven Renee M. , Heidger Susan
Published: May 2022

Rapidly developing electronics industry is striving for higher energy‐storage capability dielectric capacitors for pulsed power electronic devices. Both high dielectric permittivity and high dielectric breakdown strength are essential properties to meet the desired device performance. However, due to materials limitations and their preparation requirements, there are significant challenges which limit the use of current dielectrics in high‐energy storage capacitors. In addition material limitations such as, low dielectric permittivity, low breakdown strength, and high hysteresis loss decrease these materials' energy density and efficiency, restricting potential applications. Thus, a thorough understanding of the implementation, optimization and limitations of ferroelectric, relaxor‐ferroelectric, and anti‐ferroelectric thin films in high‐energy storage dielectric capacitors is an essential and important research topic for the incorporation of these materials in near future applications.
An efficient two‐factor authentication protocol based on elliptic curve cryptosystem with provable security
Authors: Chen Yulei , Chen Jianhua
Published: May 2022

With the gradual penetration of computers and communication networks into people's lives, more and more people begin to pay attention to the information security. Key agreement protocol provides identity authentication for participants in communication system and generates a temporary session key for participants to encrypt messages. Recently, Wang et al designed an authentication and key agreement (AKA) protocol based elliptic curve cryptosystem and proved that their scheme can resist various known attacks. In this article, we analyze the security of their scheme and demonstrate that it is vulnerable to the temporary factor leakage attacks and insider attacks. Then, based on the elliptic curve public key cryptographic algorithm, we design a secure anonymous two‐factor user AKA protocol. And we use the well‐known random oracle model (ROM) and traditional heuristic discussion to prove the security of the proposed protocol. By comparing with several existing protocols based on public key cryptography algorithm, it is found that this protocol is more secure and efficient. The security analysis shows that the protocol designed in this article can meet all kinds of security requirements and consumes the less computing resources on users and servers, and is especially suitable for the scenarios with high security and efficiency requirements.
Non‐orthogonal multiple access in backscatter communication system under the scene of the moving reader
Authors: Li Shibao , Li Quanyu , Liu Jianhang , Cui Xuerong
Published: May 2022

This article studies non‐orthogonal multiple access (NOMA) backscatter communication (BackCom) system under the scene of the moving reader. As the reader moves, the communication link between backscatter nodes (BNs) and the reader is dynamic, and the computational complexity of regrouping is high. To address these problems, a dynamic NOMA‐BackCom scheme is proposed, which consists of a dynamic multiplexing BNs scheme and a dynamic scheme of choosing the reflection coefficient. Moreover, a performance evaluation is conducted to compare the decoding rate of the proposed scheme and the traditional scheme. Simulation results show that the proposed scheme has higher decoding rate and better throughput than the traditional scheme.
Does clean energy matter? Revisiting the spillovers between energy and foreign exchange markets
Authors: Liu Yang , Qiao Tongshuai , Han Liyan
Published: May 2022

This article highlights the increasingly important role of clean energy metals in return and volatility spillovers across energy and foreign exchange markets. During the collapse of oil prices from 2014 to 2016, crude oil futures were at the center of the risk contagion; however, since the COVID‐19 pandemic broke out, the spillovers of clean energy metal futures have become one of the main sources of the risk contagion. Additionally, crude oil and the US dollar are the most important contributors to the spillovers, but further spillovers are emerging between the Chinese yuan, euro, and Japanese yen with clean energy metals.
Rift‐related multistage evolution of the Mangalwar Complex, Aravalli Craton (NW India): Evidence from elemental and Sr–Nd isotopic features of Proterozoic amphibolites
Authors: Hamidullah Ismail S. , Mondal Md. Erfan Ali , Ahmad Iftikhar , Dash Jitendra K. , Rahaman Waliur
Published: May 2022

The Banded Gneissic Complex (BGC) of the Aravalli Craton (India) comprises Archean BGC‐I (3.3–2.5 Ga) and Proterozoic BGC‐II. The BGC‐II is a mosaic of amphibolite facies namely, (a) Mangalwar Gneissic Complex (MGC), (b) Mangalwar Metasedimentary Complex (MMC), and (c) granulite‐facies Sandmata Metamorphic Complex. Here we present field, petrography and geochemical study of the Proterozoic amphibolites from the MGC and MMC. Based on field and geochemical data, the amphibolites have been characterized into three types related to rift settings (G1, G2 and G3). The G1 type occurs as dykes in the MGC and bears ocean island basalt‐type rare earth element (REE) patterns along with negative Nb and Ti anomalies, negative to positive values of εNd(t) (−0.02 to +3.96) and slightly variable initial 87Sr/86Sr (ISr) ratios. They are derived from deep mantle sources and correspond to the pre‐rift magmatic phase. The G2 type occurs as isolated patches associated with chert and is characterized by light REE (LREE) depleted and almost flat heavy REE (HREE) patterns suggesting that they were emplaced in an oceanic setting and were derived from a shallower mantle bearing positive εNd(t) (+2.87 to +6.27) and ISr = 0.7002–0.7083. This phase corresponds to the opening of the Mangalwar sedimentary basin (MMC). The G3 type occurs intercalated with metasedimentary rocks of the MMC and marked by LREE‐enriched and HREE‐depleted to flat patterns that resemble Upper Continental Crust signature, their εNd(t) mostly negative values and variable ISr also corroborate this explanation. They are believed to be derived from heterogeneous sources and represent syn‐sedimentary volcanic phases. All these signatures indicate that the amphibolites distinctly represent three phases of magmatism that occurred during pre‐rift (1.72 Ga), opening of basin (1.62 Ga) and syn‐sedimentary volcanism (1.6–1.3 Ga) in the rift‐basin and they were formed during the Proterozoic. These rifting events might have been connected with the fragmentation of Columbia.
Trace elements and in situ sulfur isotopes of pyrite from the Baiyunpu Au deposit in central Hunan, South China: Implications for gold mineralization
Authors: Gao Shang , Wu Yueyu , Shen Haonan , Han Ziyan , Chen Minxin , Wang Wei , Huang Fei , Zhao Fude
Published: May 2022

The Central Hunan metallogenic province, located in the southeastern part of the Yangtze Block, South China, is one of the most important Sb–Au metallogenic belts in China. The Baiyunpu gold deposit is one of the important Carlin‐type gold deposits occurring in Devonian sedimentary strata in Central Hunan. Optical microscopy and in situ laser ablation (multi‐collector) inductively coupled plasma mass spectrometry (LA‐[MC]‐ICP‐MS) are used to determine the texture, trace element compositions and sulfur isotope for pyrites from the pre‐ore and syn‐ore stages to constrain the sources of reduced sulfur and metals and the mechanism of gold precipitation. Four generations of pyrite were identified by petrography and pyrite compositions. Pre‐ore Py1 is characterized by relatively low concentrations of As, Au, Sb and Cu and high concentrations of Co, Ni, Bi and Pb. Py1 has positive δ34S values of 6.5–10.1‰, which we ascribe to a bacterial reduction of marine sulfate in closed marine systems, or from weak Rayleigh fractionation by bacterial sulfate reduction (BSR) or thermochemical sulfate reduction (TSR) during sedimentary‐diagenetic processes. Pre‐ore Py2 presents as rims of Py1 and contains relatively high As (69,530 ppm), Sb (123.2 ppm) and low Au (4.89 ppm). Compared with Py2, Py3 has relatively high Au (194.4 ppm) and Cu (24.6 ppm) and low As (40,801 ppm). We interpret that Py2 and Py3 could have precipitated from an Au‐free but As‐rich early hydrothermal fluids or from low‐Au and As‐rich fluids at the beginning of the ore stage. The δ34S values of Py2 and Py3 in the Baiyunpu deposit are concentrated in a narrow range of −1.2 to 1.2‰, suggesting the involvement of magmatic sulfur. Syn‐ore pyrites (Opy) are enriched in Au (517.8 ppm), As (39,719 ppm), Cu (261.9 ppm) and Sb (171.4 ppm). Irregular boundaries between Py1 and Opy suggest that the replacement may have been important for the formation of pyrites at the syn‐ore stage. The variation of As concentration in Opy1, Opy2 and Opy3 appear to have recorded fluctuations in the chemical composition of ore fluids. The δ34S values of Opy (0.1–5.9‰) are slightly higher than Py2 and Py3 due to mixing with sedimentary components with elevated δ34S values in late‐stage hydrothermal fluids. Profile analyses for Baiyunpu auriferous pyrite grains suggest that Au was positively correlated with Cu, but not with As. The correlation between Au, Cu and As in Opy may be dominated by their concentrations of ambient evolving fluids.
Liver injury after SARS‐CoV‐2 vaccination: Features of immune‐mediated hepatitis, role of corticosteroid therapy and outcome
Authors: Efe Cumali , Kulkarni Anand V. , Terziroli Beretta‐Piccoli Benedetta , Magro Bianca , Stättermayer Albert , Cengiz Mustafa , Clayton‐Chubb Daniel , Lammert Craig , Bernsmeier Christine , Gül Özlem , la Tijera Fatima Higuera‐de , Anders Margarita , Lytvyak Ellina , Akın Mete , Purnak Tugrul , Liberal Rodrigo , Peralta Mirta , Ebik Berat , Duman Serkan , Demir Nurhan , Balaban Yasemin , Urzua Álvaro , Contreras Fernando , Venturelli Maria Grazia , Bilgiç Yılmaz , Medina Adriana , Girala Marcos , Günşar Fulya , Londoño Maria‐Carlota , Androutsakos Theodoros , Kisch Ayelen , Yurci Alper , Güzelbulut Fatih , Çağın Yasir Furkan , Avcı Enver , Akyıldız Murat , Dindar‐Demiray Emine Kübra , Harputluoğlu Murat , Kumar Rahul , Satapathy Sanjaya K. , Mendizabal Manuel , Silva Marcelo , Fagiuoli Stefano , Roberts Stuart K. , Soylu Neşe Karadağ , Idilman Ramazan , Yoshida Eric M. , Montano‐Loza Aldo J. , Dalekos George N. , Ridruejo Ezequiel , Schiano Thomas D. , Wahlin Staffan
Published: May 2022

Background and Aims

A few case reports of autoimmune hepatitis–like liver injury have been reported after severe acute respiratory syndrome coronavirus 2 (SARS‐CoV‐2) vaccination. We evaluated clinical features, treatment response and outcomes of liver injury following SARS‐CoV‐2 vaccination in a large case series.

Approach and Results

We collected data from cases in 18 countries. The type of liver injury was assessed with the R‐value. The study population was categorized according to features of immune‐mediated hepatitis (positive autoantibodies and elevated immunoglobulin G levels) and corticosteroid therapy for the liver injury. We identified 87 patients (63%, female), median age 48 (range: 18–79) years at presentation. Liver injury was diagnosed a median 15 (range: 3–65) days after vaccination. Fifty‐one cases (59%) were attributed to the Pfizer‐BioNTech (BNT162b2) vaccine, 20 (23%) cases to the Oxford‐AstraZeneca (ChAdOX1 nCoV‐19) vaccine and 16 (18%) cases to the Moderna (mRNA‐1273) vaccine. The liver injury was predominantly hepatocellular (84%) and 57% of patients showed features of immune‐mediated hepatitis. Corticosteroids were given to 46 (53%) patients, more often for grade 3–4 liver injury than for grade 1–2 liver injury (88.9% vs. 43.5%, p = 0.001) and more often for patients with than without immune‐mediated hepatitis (71.1% vs. 38.2%, p = 0.003). All patients showed resolution of liver injury except for one man (1.1%) who developed liver failure and underwent liver transplantation. Steroid therapy was withdrawn during the observation period in 12 (26%) patients after complete biochemical resolution. None had a relapse during follow‐up.

Conclusions

SARS‐CoV‐2 vaccination can be associated with liver injury. Corticosteroid therapy may be beneficial in those with immune‐mediated features or severe hepatitis. Outcome was generally favorable, but vaccine‐associated liver injury led to fulminant liver failure in one patient.
Development and thermal performance evaluation of solar parabolic dish based on fiber‐reinforced plastic
Authors: Kumar Vikrant , Yadav Avadhesh
Published: May 2022

This paper illustrates the design and fabrication of a 76° rim angle solar parabolic dish concentrator with low cost based on fiberglass‐reinforced for heating of heat transfer fluid using the hand layup process. Numerous advantages of fiberglass material include corrosion resistance, lightweight, design flexibility, quick installation time, and low cost makes it suitable for fabrication. The concave surface on which the reflective sheets are mounted is made to a high degree of perfection. The design process, as well as the complete fabrication process, are elaborately discussed in this article. The thermal efficiency of the newly constructed fiberglass‐reinforced solar parabolic dish concentrator was assessed by heating the heat transfer fluid in the conical cavity receiver, which was cycled from the sump via a gear pump and flexible stainless steel connecting pipes. The maximum value of heat transfer fluid temperature achieved was 194°C at the sump. The average thermal efficiency achieved for indoor heating at the sump was 17.42%, 17.16%, and 17.21%, respectively, during Experiments 1, 2, and 3. The results indicate that this system is acceptable for indoor cooking in the kitchen, as the system achieves temperatures between 150°C and 194°C.
The importance of continental evaporation for precipitation in Colombia: A baseline combining observations from stable isotopes and modelling moisture trajectories
Authors: Escobar Maritza , Hoyos Isabel , Nieto Raquel , Villegas Juan Camilo
Published: May 2022

The hydroclimatology of Northern South America responds to the coupling between the Pacific and Atlantic oceans, the Amazon–Andes interactions, and the orographic barrier of the regional Andes. The relative contributions of oceanic and terrestrial moisture sources have been mostly evaluated in modelling studies, with limited observational data for validation. We combine observations from stable isotopes in precipitation and output from the Lagrangian moisture trajectory tracking model FLEXPART to characterize and contrast the relative contribution of oceanic (from the Atlantic and the Pacific) and terrestrial (from different regions in the continent) moisture sources to mean monthly precipitation in the Andes and Caribbean regions of Colombia. Our results indicate that most moisture becoming rain in the region has an atmospheric residence time that deviates from commonly assumed 10 days. These residence times vary between source and sink regions from 1 day in the case of recycling to more than 10 days in Andean precipitation originating in the Atlantic Ocean. Common integration times for both regions from all sources are commonly in the order of three to 7 days. Most precipitation in the region comes from terrestrial sources including moisture recycling from the same region (>30% for all months), the Orinoco River basin (up to 28% in April), and the northern Amazon basin (up to 17% in June, July, and August); followed by individually considered oceanic sources including the Tropical South Pacific (up to 30% monthly in October, November and December) and Tropical North Atlantic (up to 30% monthly for January). The fact that a significant proportion of rainfall is recycled highlights that water availability in the Andean and Caribbean regions of Colombia could potentially be altered by current widespread and pervasive changes in vegetation cover. More generally, our results highlight the need to assess the hydrological consequences of land cover change in South America, particularly in a country like Colombia where water, food, and energy security all depend directly on precipitation.
Challenges faced by university students during the COVID‐19: An international study in five countries during the early phase of the pandemic
Authors: Pat‐Horenczyk Ruth , Schiff Miriam , Arënliu Aliriza , Zasiekina Larysa , Kagialis Antonios , Ferreira Nuno , Nesterko Yuriy , Glaesmer Heide , Fernández‐Alcántara Manuel , Benbenishty Rami
Published: May 2022

This study focused on the specific challenges of university students in the face of the COVID‐19 pandemic and examined similarities and differences in COVID‐related concerns and difficulties in functioning in samples of undergraduate students in five countries. A sample of 4306 undergraduate university students (43.8% males, 56.2% females) from Israel, Kosovo, Ukraine, Cyprus and Germany participated in an anonymous online survey during the first wave of the pandemic, between March and June 2020. Study variables included the assessment of the exposure to COVID‐19, perceived health status, specific COVID‐related concerns and functional difficulties, social support, and the perceived level of coping. Similar concerns about the uncertainty regarding the termination of the health crisis and worry for the health of family members were identified as the most common concerns in the five countries. Challenges in online learning and financial difficulties were rated as the most central difficulties. Both COVID‐related concerns and COVID‐related difficulties predicted lower levels of perceived coping. Greater social support was associated with better perceived coping. Policymakers should be informed by the accumulating research showing the substantive relationships between academic difficulties and perceived COVID‐related distress and coping.