bluuebunny/crossref_metadata_2025 huggingface dataset:
Pollination effectiveness of European honeybee, Apis mellifera (Hymenoptera: Apidae), in an Oriental persimmon, Diospyros kaki (Ericales: Ebenaceae), orchard
Authors: Nakamura Shoko , Yamamoto Shunsuke , Sawamura Nobuo , Nikkeshi Aoi , Kishi Shigeki , Kamo Tsunashi
Published: September 2020

Most common cultivars of Oriental (or Japanese) persimmon, Diospyros kaki Thunb. (Ericales: Ebenaceae), set mostly female flowers and require pollen from male flowers of other cultivars for pollination. Growers often introduce the European honeybee, Apis mellifera L. (Hymenoptera: Apidae), into their orchards to promote pollination. Here, we investigated the pollination effectiveness of A. mellifera for D. kaki ‘Saijo,’ by monitoring flower visitors, analyzing pollen grains on bees’ body surfaces, and comparing the number of mature seeds in fruits among years with different pollinator availabilities. Apis mellifera and the bumblebee Bombus ardens ardens Smith (Hymenoptera: Apidae) were the major visitors for 3 years, although their dominance varied among years. The number of mature seeds was positively correlated with the number of B. ardens ​ardens visiting D. kaki flowers, but not with that of A. mellifera. Apis mellifera might be less efficient because visitors to female flowers carried significantly fewer pollen grains on their body surfaces than those of B. ardens ​ardens. Analysis of pollen loads of honeybees captured at their nest entrance suggested their preference for red clover, Trifolium pratense L. (Fabales: Fabaceae), and Toxicodendron spp. (Sapindales: Anacardiaceae), over D. kaki as a pollen source in our study site. The effectiveness of A. mellifera on D. kaki pollination should be carefully evaluated considering the effects of coexisting floral and pollinator species.
Current developments in German pension schemes: What are the benefits of the new target pension?
Authors: Chen An , Rach Manuel
Published: September 2020

We analyze the newly introduced German occupational pension scheme called target pension (“Zielrente”), which links the beneficiaries’ benefits during the retirement phase to the mortality experienced among the pension beneficiaries and the performance of the financial market, from a pension beneficiary’s perspective. We model the contract payoffs related to the target pension according to the new enhancement law on German occupational law. Specifically, we include two parameters in the plan design, one to control the surplus participation and one to control the loss participation. These parameters are chosen in such a way that the initial wealth of the retiree equals the initial value of the target pension. With the help of expected lifetime utility and wealth equivalent, we find that the target pension provides a meaningful supplement to the first and third pillar. Further, we find some comparative advantages of the target pension over the traditional pure defined benefit and some defined contribution plans from a policyholder’s point of view. Our analysis with reasonable parameter choices shows that target pension plans can be outperformed by defined contribution plans with variable annuities, while the latter are accompanied by a considerably higher ruin probability.
Narrow pasts and futures: how frames of sustainability transformation limit societal change
Authors: Priebe Janina , Mårald Erland , Nordin Annika
Published: September 2020

Two frames dominate present-day interpretations of sustainability and approaches to sustainability transformation in national and global policy arenas. One frame relates to transformation in global environmental governance that promotes goal-oriented agendas. The other frame relates to earth system sciences where sustainability transformation means breaking the devastating trends of the Anthropocene. In this paper, we examine the historical and cultural underpinnings of these two frames, each invoking particular relations and approaches to sustainability transformation. Our contribution is to discuss the role of the past in these frames and to illuminate how current outlooks toward the future still rely on principles that emerged in eighteenth- and nineteenth-century Europe and thus hinder alternative approaches to transformation in the present.
Common fixed point iterations for a class of multi-valued mappings in $$\mathbf {CAT}(0)$$ spaces
Authors: Saleh Khairul , Fukhar-ud-din Hafiz
Published: September 2020

In this work, we propose an iterative scheme to approach common fixed point(s) of a finite family of generalized multi-valued nonexpansive mappings in a CAT(0) space. We establish and prove convergence theorems for the algorithm. The results are new and interesting in the theory of $$CAT\left( 0\right) $$

C
A
T

0

spaces and are the analogues of corresponding ones in uniformly convex Banach spaces and Hilbert spaces.
A meshfree generalized finite difference method for solution mining processes
Authors: Michel Isabel , Seifarth Tobias , Kuhnert Jörg , Suchde Pratik
Published: September 2020

Experimental and field investigations for solution mining processes have improved intensely in recent years. Due to today’s computing capacities, three-dimensional simulations of potential salt solution caverns can further enhance the understanding of these processes. They serve as a “virtual prototype” of a projected site and support planning in reasonable time. In this contribution, we present a meshfree generalized finite difference method (GFDM) based on a cloud of numerical points that is able to simulate solution mining processes on microscopic and macroscopic scales, which differ significantly in both the spatial and temporal scales. Focusing on anticipated industrial requirements, Lagrangian and Eulerian formulations including an Arbitrary Lagrangian–Eulerian (ALE) approach are considered.
Lessons for the clinical nephrologist: recurrence of nephrotic syndrome induced by SARS-CoV-2
Authors: Doevelaar Adrian A. N. , Hölzer Bodo , Seibert Felix S. , Bauer Frederic , Stervbo Ulrik , Rohn Benjamin J. , Zgoura Panagiota , Schenker Peter , Vonbrunn Eva , Amann Kerstin , Viebahn Richard , Babel Nina , Westhoff Timm H.
Published: September 2020

SARS-CoV-2 is characterized by a multiorgan tropism including the kidneys. Recent autopsy series indicated that SARS-CoV-2 can infect both tubular and glomerular cells. Whereas tubular cell infiltration may contribute to acute kidney injury, data on a potential clinical correlative to glomerular affection is rare. We describe the first case of nephrotic syndrome in the context of COVID-19 in a renal transplant recipient. A 35 year old male patient received a kidney allograft for primary focal segmental glomerulosclerosis (FSGS). Three months posttransplant a recurrence of podocytopathy was successfully managed by plasma exchange, ivIG, and a conversion from tacrolimus to belatacept (initial proteinuria > 6 g/l decreased to 169 mg/l). Six weeks later he was tested positive for SARS-CoV-2 and developed a second increase of proteinuria (5.6 g/l). Renal allograft biopsy revealed diffuse podocyte effacement and was positive for SARS-CoV-2 in RNA in-situ hybridation indicating a SARS-CoV-2 associated recurrence of podocytopathy. Noteworthy, nephrotic proteinuria resolved spontaneously after recovering from COVID-19. The present case expands the spectrum of renal involvement in COVID-19 from acute tubular injury to podocytopathy in renal transplant recipients. Thus, it may be wise to test for SARS-CoV-2 prior to initiation of immunosuppression in new onset glomerulopathy during the pandemic.
Heterogeneity matters: temporary employment, productivity and wages in Italian firms
Authors: Cirillo Valeria , Ricci Andrea
Published: September 2020

This study analyses the relationship between flexible employment, productivity and wages, along their distributions. We use an original firm-level dataset, which combines information on workplace characteristics fromRilevazione su Imprese e Lavoro(RIL) with theAnalisi Informatizzata delle Aziende Italiane(AIDA) balance sheet information for the universe of Italian non-agriculture/financial corporations. We employ different quantile regression models to panel data and find, first, that use of temporary contracts is associated to a reduction in labour productivity and wages at each point in the corresponding distribution; and second, that the negative relationship between labour productivity and wages decreases in magnitude along the quantiles of the productivity and wage distributions, suggesting that low-productive/low-wage firms use temporary employment to permanently staff positions and to compress labour costs.
Subjective annotation for a frame interpolation benchmark using artefact amplification
Authors: Men Hui , Hosu Vlad , Lin Hanhe , Bruhn Andrés , Saupe Dietmar
Published: September 2020

Current benchmarks for optical flow algorithms evaluate the estimation either directly by comparing the predicted flow fields with the ground truth or indirectly by using the predicted flow fields for frame interpolation and then comparing the interpolated frames with the actual frames. In the latter case, objective quality measures such as the mean squared error are typically employed. However, it is well known that for image quality assessment, the actual quality experienced by the user cannot be fully deduced from such simple measures. Hence, we conducted a subjective quality assessment crowdscouring study for the interpolated frames provided by one of the optical flow benchmarks, the Middlebury benchmark. It contains interpolated frames from 155 methods applied to each of 8 contents. For this purpose, we collected forced-choice paired comparisons between interpolated images and corresponding ground truth. To increase the sensitivity of observers when judging minute difference in paired comparisons we introduced a new method to the field of full-reference quality assessment, called artefact amplification. From the crowdsourcing data (3720 comparisons of 20 votes each) we reconstructed absolute quality scale values according to Thurstone’s model. As a result, we obtained a re-ranking of the 155 participating algorithms w.r.t. the visual quality of the interpolated frames. This re-ranking not only shows the necessity of visual quality assessment as another evaluation metric for optical flow and frame interpolation benchmarks, the results also provide the ground truth for designing novel image quality assessment (IQA) methods dedicated to perceptual quality of interpolated images. As a first step, we proposed such a new full-reference method, called WAE-IQA, which weights the local differences between an interpolated image and its ground truth.
Modelling the Quest for Status in Ancient Greece: Paying for Liturgies
Authors: Tridimas George
Published: September 2020

The substantive view of the ancient economy argues that social considerations and especially the quest for status featured prominently in ancient Greece. Paying for liturgies, the private finance of public expenditure by wealthy individuals, offered the opportunity to acquire status by choosing the level of contributions to outperform rival providers. Effectively, liturgies were a system of finance of public provision through redistributive taxation sidestepping state administration of taxes and expenditures. Applying the insights of the economic approach to status, the paper examines status competition in ancient Athens and compares paying for liturgies with a hypothetical system of explicit income taxation of the rich. It is concluded that status seeking increased aggregate provision of public goods. The results formalise important aspects of substantivism and illustrate the value of formal economic analysis in the investigation of the ancient Greek economy.
Platelet Rich Plasma as a Treatment Method for Rotator Cuff Tears
Authors: Hitchen Jack , Wragg Nicholas M. , Shariatzadeh Maryam , Wilson Samantha L.
Published: September 2020

The prevalence of the rotator cuff (RC) tears is ~ 21% in the general population, with higher incidences in individuals over 50. Irrespective of surgical repair techniques employed, re-tear rates are alarmingly high, indicating the need for improvement to the current treatment methods. A method that has recently increased in popularity is the administration of platelet-rich-plasma (PRP), as it has been proposed to significantly encourage and improve healing in a plethora of musculoskeletal tissues, although experimental conditions and results are often variable. This review aims to critically evaluate current literature concerning the use of PRP, specifically for the treatment of RC tears. There are ongoing conflicts debating the effectiveness of PRP to treat RC tears; with literature both in favour and against its use either having profound methodological weaknesses and/or limited applicability to most individuals with RC tears. There are numerous factors that may influence effectiveness, including the subgroup of patients studied and the timing and method of PRP delivery. Thus, in order to ascertain the clinical effectiveness of PRP for RC tears, the preparation protocol and composition of PRP must be standardised, so an accurate assessment and comparisons can be undertaken. Prior to clinical realisation, there is a requirement for a defined, standardised, quality-controlled protocol/procedure considering composition/formulation (of PRP); injury severity, dosage, frequency, timings, controls used, patient group, and rehabilitation programmes. Nevertheless, it is concluded that the initial step to aid the progression of PRP to treat RC tears is to standardise its preparation and delivery.
Quaternion-Based Constrained Dynamics Modeling of a Space Manipulator with Flexible Arms for Servicing Tasks
Authors: Kłak Marcin , Jarzębowska Elżbieta
Published: September 2020

Background

The paper presents modeling of space manipulators whose structures are composed of rigid and flexible components. Due to their applications for variety of servicing missions, their dynamics and attitude are described using quaternions. Parameterization by the quaternions does not share Euler angles’ drawbacks and is computationally more efficient. Another challenge is the motion equations derivation method.

Methods

Due to poor scalability of Lagrange method equations, authors decided to model the space robot as a set of links subjected to position constraints. The elastic effects are modeled with the assumed mode method successfully applied to a variety of ground manipulators with flexible links. The constrained dynamics approach and the assumed mode method are combined to derive a comprehensive space manipulator dynamics. Its dynamic model is readily scalable in terms of number of both rigid and flexible robotic arms and links.

Conclusions

The paper contributes to the development of effective quaternion-based constrained dynamics for space structures equipped with flexible links. The theory is illustrated by simulation studies of an example of a space manipulator attitude dynamics.
East Africa Invests in Strategies to Manage E-Waste
Authors: Mafaranga Hope
Published: September 2020

As Uganda develops its e-waste policy, neighboring Rwanda establishes a broad-based plan involving incentives and high-tech facilities.
Steadying Mid-Ocean Ridge Spreading Rates
Authors: Wheeling Kate
Published: September 2020

Researchers used an up-to-date global magnetic anomaly data set to track the history of magnetic field reversals and obtain more accurate estimates of tectonic spreading rates.
Every Vote Counts: Final Slate for 2020 AGU Elections
Authors: Davidson Eric
Published: September 2020

Voting is a right and a responsibility of membership, and your vote is important!
A User‐Friendly Workbook to Facilitate Rapid and Accurate Rare Earth Element Analyses by ICP‐MS for Multispiked Samples
Authors: Wu Y. , Pena L. D. , Goldstein S. L. , Basak C. , Bolge L. L. , Jones K. M. , McDaniel D. K. , Hemming S. R.
Published: September 2020

The rare earth elements (REEs) are widely used as geochemical tracers in the earth, planetary, and ocean sciences. Inductively coupled plasma‐mass spectrometry (ICP‐MS) has become the method of choice to analyze REE concentrations because it can rapidly measure the entire REE spectrum at the same time. This Technical Report presents a user‐friendly “REE Calculation Workbook” in Microsoft Excel to be used for calculating REE abundances in samples equilibrated with a multielement REE spike. This Workbook can be conveniently used to calculate REE concentrations in natural samples for spiked and unspiked elements measured by ICP‐MS. For the spiked elements, their concentrations are calculated using isotope dilution equations. Using these spiked elements as references, concentrations of the four mono‐isotopic REE elements, and other REE elements that are treated as mono‐isotopic elements (in our case, La and Lu), can be calculated. The REE Workbook can be easily set up for use with different REE spikes. Evaluation of our analytical quality using a quadrupole ICP‐MS on 10‐ml‐sized seawater samples shows that our analyses are comparable to high‐precision thermal ionization mass spectrometry (TIMS) studies, with much less time spent processing and analyzing, and with the added advantages of determining mono‐isotopic elements. An important result is the clear demonstration of enrichments in Gd and Er compared to neighboring elements in seawater samples. In addition, we compare and evaluate commonly used reference standards BCR‐1, Post‐Archean Australian Shale (PAAS), and North American Shale Composite (NASC).
First Global‐Scale Synoptic Imaging of Solar Eclipse Effects in the Thermosphere
Authors: Aryal Saurav , Evans J. S. , Correira John , Burns Alan G. , Wang Wenbin , Solomon Stanley C. , Laskar Fazlul I. , McClintock William E. , Eastes Richard W. , Dang Tong , Lei Jiuhou , Liu Huixin , Jee Geonhwa
Published: September 2020

A total solar eclipse occurred in the Southern Hemisphere on 2 July 2019 from approximately 17 to 22 UT. Its effect in the thermosphere over South America was imaged from geostationary orbit by NASA's Global‐scale Observation of Limb and Disk (GOLD) instrument. GOLD observed a large brightness reduction (>80% around totality) in OI 135.6 nm and N2 LBH band emissions compared to baseline measurements made 2 days prior. In addition, a significant enhancement (with respect to the baseline) in the ΣO/N2 column density ratio (~80%) was observed within the eclipse's totality. This enhancement suggests that the eclipse induced compositional changes in the thermosphere. After the eclipse passed, a slight enhancement in ΣO/N2 column density ratio (~7%) was also seen around the totality path when compared to measurements before the eclipse. These observations are the first synoptic imaging measurements of an eclipse's thermospheric effects with the potential to drastically improve and test our understanding of how the thermosphere responds to rapid, localized changes in solar short wavelength radiation.
Solutions for Subtidal Flow in Channels and Estuaries Under Different Integral Constraints
Authors: Whitney Michael M. , Jia Yan
Published: September 2020

This study builds on Huntley and Ryan (2018, https://doi.org/10.1002/2017JC012748) and related prior works on channels and estuaries by considering solutions for the same subtidal dynamics but with alternative integral flow constraints. Prior solutions do not have a truly two‐dimensional (2‐D) flow field, as axial changes in the axial flow are implied. Three constraint types are considered: the Constant case with spatially constant density gradients constrained with section‐integrated flow (as in prior works), Semi‐Variable case with a constant axial density gradient and laterally variable lateral density gradient constrained with depth‐integrated lateral flow, and Variable case with spatially variable density gradients in both directions constrained with depth‐integrated axial and lateral flows. The Semi‐Variable and Variable cases can produce solutions with truly 2‐D flow if the depth‐integrated lateral flow is set to zero everywhere. Differences among solutions are illustrated with idealized and realistic applications from Huntley and Ryan (2018, https://doi.org/10.1002/2017JC012748). For the idealized application, the Constant case and the Semi‐Variable case with 2‐D flow have clear differences in axial velocity and stark contrasts in lateral flow (and density gradients). For the Nares Strait application, the Variable case with observed depth‐averaged axial and lateral velocities is best able to represent the fastest observed down‐channel velocities, the weak reversed flow on one side of the channel, and the observed lateral flow structure. Overall, selecting different integral constraints on flow conspicuously changes the subtidal flow, opens up new possibilities for truly 2‐D flow solutions, and provides additional flexibility for representing observed conditions in realistic situations.
An Aridity Index‐Based Formulation of Streamflow Components
Authors: Meira Neto Antonio Alves , Roy Tirthankar , de Oliveira Paulo Tarso S. , Troch Peter A.
Published: September 2020

Direct runoff and baseflow are the two primary components of total streamflow, and their accurate estimation is indispensable for a variety of hydrologic applications. While direct runoff is the quick response stemming from surface and shallow subsurface flow paths and is often associated with floods, baseflow represents the groundwater contribution from stored sources (e.g., groundwater) to streams and is crucial for environmental flow regulations, and water supply, among others. L'vovich (1979) proposed a two‐step water balance partitioning, where precipitation is divided into direct runoff and catchment wetting, followed by the disaggregation of the latter into baseflow and evapotranspiration. Here, we investigate the role of the aridity index (ratio between mean‐annual potential evapotranspiration and precipitation) in controlling the long‐term (mean‐annual) fluxes of direct runoff and baseflow. We present an analytical solution beginning with similar assumptions as proposed by Budyko (1974), leading to two complementary expressions for the two fluxes. The aridity index explained 77% and 89% of variability in direct runoff and baseflow from 378 catchments within the continental United States, while our formulations were able to reproduce the patterns of water balance partitioning proposed by L'vovich (1979) at the mean‐annual timescale. Our approach can be used to further understand how climate and landscape controls the terrestrial water balance at mean‐annual timescales, while also representing a step toward the prediction of baseflow and direct runoff at ungauged basins.
Membrane-tethering of cytochrome c accelerates regulated cell death in yeast
Authors: Toth Alexandra , Aufschnaiter Andreas , Fedotovskaya Olga , Dawitz Hannah , Ädelroth Pia , Büttner Sabrina , Ott Martin
Published: September 2020

Intrinsic apoptosis as a modality of regulated cell death is intimately linked to permeabilization of the outer mitochondrial membrane and subsequent release of the protein cytochrome c into the cytosol, where it can participate in caspase activation via apoptosome formation. Interestingly, cytochrome c release is an ancient feature of regulated cell death even in unicellular eukaryotes that do not contain an apoptosome. Therefore, it was speculated that cytochrome c release might have an additional, more fundamental role for cell death signalling, because its absence from mitochondria disrupts oxidative phosphorylation. Here, we permanently anchored cytochrome c with a transmembrane segment to the inner mitochondrial membrane of the yeast Saccharomyces cerevisiae, thereby inhibiting its release from mitochondria during regulated cell death. This cytochrome c retains respiratory growth and correct assembly of mitochondrial respiratory chain supercomplexes. However, membrane anchoring leads to a sensitisation to acetic acid-induced cell death and increased oxidative stress, a compensatory elevation of cellular oxygen-consumption in aged cells and a decreased chronological lifespan. We therefore conclude that loss of cytochrome c from mitochondria during regulated cell death and the subsequent disruption of oxidative phosphorylation is not required for efficient execution of cell death in yeast, and that mobility of cytochrome c within the mitochondrial intermembrane space confers a fitness advantage that overcomes a potential role in regulated cell death signalling in the absence of an apoptosome.
Mitochondrial dysfunction in fibrotic diseases
Authors: Li Xinyu , Zhang Wei , Cao Qingtai , Wang Zeyu , Zhao Mingyi , Xu Linyong , Zhuang Quan
Published: September 2020

Although fibrosis is a common pathological feature of most end-stage organ diseases, its pathogenesis remains unclear. There is growing evidence that mitochondrial dysfunction contributes to the development and progression of fibrosis. The heart, liver, kidney and lung are highly oxygen-consuming organs that are sensitive to mitochondrial dysfunction. Moreover, the fibrotic process of skin and islet is closely related to mitochondrial dysfunction as well. This review summarized emerging mechanisms related to mitochondrial dysfunction in different fibrotic organs and tissues above. First, it highlighted the important elucidation of mitochondria morphological changes, mitochondrial membrane potential and structural damage, mitochondrial DNA (mtDNA) damage and reactive oxidative species (ROS) production, etc. Second, it introduced the abnormality of mitophagy and mitochondrial transfer also contributed to the fibrotic process. Therefore, with gaining the increasing knowledge of mitochondrial structure, function, and origin, we could kindle a new era for the diagnostic and therapeutic strategies of many fibrotic diseases based on mitochondrial dysfunction.
Tumor-triggered personalized microRNA cocktail therapy for hepatocellular carcinoma
Authors: Shao Shiyi , Hu Qida , Wu Wangteng , Wang Meng , Huang Junming , Zhao Xinyu , Tang Guping , Liang Tingbo
Published: September 2020

miRNA cocktail therapy based on pH-responsive nanoparticles featuring PEG detachment and size transformation is a potential strategy for HCC treatment.
A dynamic remodeling bio-mimic extracellular matrix to reduce thrombotic and inflammatory complications of vascular implants
Authors: Xiang Zehong , Chen Runhai , Ma Zhifang , Shi Qiang , Ataullakhanov Fazoil I. , Panteleev Mikhail , Yin Jinghua
Published: September 2020

Inspired by the remodeling of the extracellular matrix in response to pathological changes and disease, the ECM was constructed on an implant that responded to inflammation and self-adaptively reduced inflammatory and thrombotic complications.
Synthesis of a B12–BODIPY dyad for B12-inspired photochemical transformations of a trichloromethylated organic compound
Authors: Anai Yuki , Shichijo Keita , Fujitsuka Mamoru , Hisaeda Yoshio , Shimakoshi Hisashi
Published: September 2020

A B12complex–BODIPY dyad was synthesized by peripheral modification of cobalamin derivatives.
Carbonylative cycloaddition between two different alkenes enabled by reactive directing groups: expedited construction of bridged polycyclic skeletons
Authors: Gao Bingjian , Zou Suchen , Yang Guoqing , Ding Yongzheng , Huang Hanmin
Published: September 2020

A novel palladium-catalyzed highly selective hydrocarbonylative cycloaddition reaction with two different alkenes in the presence of CO enabled by a reactive directing-group is developed, which offers efficient access to bicyclo[2,2,2]lactones.
Highly sensitive detection of cobalt through fluorescence changes in β-cyclodextrin-bimane complexes
Authors: Pramanik Apurba , Amer Sara , Grynszpan Flavio , Levine Mindy
Published: September 2020

Cobalt detection is accomplished via efficient fluorescence quenching of a bimane-β-cyclodextrin complex, both in solution and in the solid state.
Unraveling the mechanisms of S-doped carbon nitride for photocatalytic oxygen reduction to H2O2
Authors: Tong Yawen , Wei Changgeng , Li Yi , Zhang Yongfan , Lin Wei
Published: September 2020

First-principles calculations reveal the mechanisms of thermodynamically feasible process for the selective oxygen photoreduction to H2O2in the S-doped melon-based carbon nitride.
Deeply understanding the Zn anode behaviour and corresponding improvement strategies in different aqueous Zn-based batteries
Authors: Hao Junnan , Li Xiaolong , Zeng Xiaohui , Li Dan , Mao Jianfeng , Guo Zaiping
Published: September 2020

The differences and similarities of the Zn electrode in both alkaline and mild electrolytes have been thoroughly clarified.
Products and mechanism of thermal decomposition of chlorpyrifos under inert and oxidative conditions
Authors: Weber Nathan H. , Stockenhuber Sebastian P. , Benhelal Emad , Grimison Charles C. , Lucas John A. , Mackie John C. , Stockenhuber Michael , Kennedy Eric M.
Published: September 2020

A flow reactor study and quantum chemical calculations that report the products detected under inert and oxidative conditions from the decomposition of chlorpyrifos.
Tracer-based characterization of source variations of PM2.5 and organic carbon in Shanghai influenced by the COVID-19 lockdown
Authors: Zhu Shuhui , Wang Qiongqiong , Qiao Liping , Zhou Min , Wang Shan , Lou Shengrong , Huang Dandan , Wang Qian , Jing Shengao , Wang Hongli , Chen Changhong , Huang Cheng , Yu Jian Zhen
Published: September 2020

Contributions of primary and secondary sources to PM2.5 and organic carbon in Shanghai were quantified before and during the COVID-19 lockdown period.
Magic-angle spinning NMR spectroscopy provides insight into the impact of small molecule uptake by G-quartet hydrogels
Authors: Manjunatha Reddy G. N. , Peters Gretchen M. , Tatman Ben P. , Rajan Teena S. , Kock Si Min , Zhang Jing , Frenguelli Bruno G. , Davis Jeffery T. , Marsh Andrew , Brown Steven P.
Published: September 2020

Compositions, local structures and interactions of medicinally relevant small molecules added to G-quartet hydrogels are characterized using gel-state NMR spectroscopy.
Polyethylene glycol-bonded triethylammonium l-prolinate: a new biodegradable amino-acid-based ionic liquid for the one-pot synthesis of bis(pyrazolyl)methanes as DNA binding agents
Authors: Kordnezhadian Reza , Shekouhy Mohsen , Karimian Somaye , Tavaf Zohreh , Malek-Hosseini Saeed , Shahsavani Mohammad Bagher , Amirghofran Zahra , Yousefi Reza , Khalafi-Nezhad Ali
Published: September 2020

[PEG-TEA]LP, as a new biodegradable ionic liquid catalyst, was successfully synthesized, characterized, and applied to the one-pot pseudo-five-component synthesis of bis(pyrazolyl)methanes.
The effect of bisimidazolium-based ionic liquids on a bimolecular substitution process. Are two head(group)s better than one?
Authors: Liu Kenny T.-C. , Haines Ronald S. , Harper Jason B.
Published: September 2020

Bisimidazolium-based ionic liquids generally result in greater rate constants than the corresponding monocationic salts. The effect depends on the length of the bridging chain; likely due to a change in the mode of interactions in solution.
Autoxidation of polythiophene tethered to carbon cloth boosts its electrocatalytic activity towards durable water oxidation
Authors: Zhang Shi-Nan , Xue Zhong-Hua , Lin Xiu , Lin Yun-Xiao , Su Hui , Hirano Shin-Ichi , Li Xin-Hao , Chen Jie-Sheng
Published: September 2020

Autoxidation of sulfur atoms in polythiophene boosts both its activity and stability for the oxygen evolution reaction.
Low‐latency BP decoder of polar code with alternate‐structure scheduling scheme
Authors: Zhang Xiaojun , Yan Xiaofeng , Cui Jianming , Dong Yanfei
Published: September 2020

In this Letter, a new scheduling scheme for belief propagation (BP) is proposed to reduce the decoding latency. All the stages update messages at the same time, it improves the reliability and accelerates the decoding convergence. The authors also remove the last stage of factor graph to reduce computational complexity. Simulations show that the average decoding latency of a (1024,512) polar code is reduced to 29.4 clocks.
Alternating panel charge sharing technique for touch screen panel self‐capacitance sensing IC
Authors: Seong S. , Lee S. , Bae S. , Lee M.
Published: September 2020

This Letter presents a self‐capacitance sensing (SCS) technique for touch screen panel with the alternating panel charge sharing (APCS) that effectively suppresses low‐frequency noise and achieves a better signal‐to‐noise ratio (SNR). With the proposed APCS‐based SCS, SNR is improved in measurement by 7.65 dB compared to the conventional panel charge sharing‐based SCS.
Gate leakage compensation technique for self‐cascode based voltage references
Authors: Olivera F. , Petraglia A.
Published: September 2020

This communication describes a gate leakage compensation technique to ensure wide‐temperature operation and wide‐supply regulation of traditional self‐cascode based voltage references in deep nanometre nodes ( ). Extensive simulations in 28 nm ultra‐thin buried oxide fully depleted silicon‐on‐insulator CMOS process show that the proposed 4‐transistor topology can operate down to 0.2 V, generating a reference voltage of 98.2 mV with mean and best temperature coefficients of 68.9 and , respectively, from to .
Photonic configurable logic block for digital photonic integrated circuits
Authors: Meerasha M.A. , Pandiyan K.
Published: September 2020

In this Letter, the authors designed a photonic configurable logic block (pCLB) with Mach–Zehnder modulator as a universal photonic gate (UPG) using electro‐optic mechanism. The UPG is capable of performing all the logical operations with the help of FPGA as a configuration controller. The functionality and its suitability is verified by forming a pCLB of ten UPGs, which finds applications in digital photonics. For the design of pCLB, traditional electronic design automation tools are used. The pCLB provides features namely scalability and modular approach, for the reconfigurable digital photonic integrated circuits. The photonic gate designed using a two‐dimensional finite difference time domain approach shows a crosstalk‐free operation with a negligible transmission loss of 0.18 dB and flexible switching control compared to the existing MZI‐based photonic gate.
Baseline wander and power‐line interference elimination of ECG signals using efficient signal‐piloted filtering
Authors: Mian Qaisar Saeed
Published: September 2020

A signal‐piloted linear phase filtering tactic for removing baseline wander and power‐line interference from the electrocardiogram (ECG) signals is suggested. The system is capable of adjusting its parameters by following the incoming signal variations. It renders the processing of lesser samples by inferior order filters. The applicability is demonstrated by using the MIT‐BIH ECG database. The precision of the approach is also studied regarding the signal‐to‐noise ratio (SNR). Results showed that the proposed method achieves a 2.18‐fold compression gain and notable computational efficiency over conventional counterpart while securing an analogous output SNR. A comparison of the designed solution is made with the contemporary empirical mode decomposition with Kalman filtering and eigenvalue decomposition based tactics. Results show that the suggested method performs better in terms of output SNR for the studied cases.
Adaptive tracking control for a class of stochastic non‐linear systems with input delay: a novel approach based on multi‐dimensional Taylor network
Authors: Han Yu‐Qun
Published: September 2020

In this study, by means of the techniques of adaptive multi‐dimensional Taylor network (MTN) control, the tracking problem of a class of stochastic non‐linear systems with input delay is studied. Firstly, based on the Padé approximation method, a new variable is employed to overcome the problem of input delay, and MTNs are applied to estimate the non‐linear functions in the design of the controller. Secondly, an adaptive MTN controller design scheme is developed in the framework of backstepping. Thirdly, the stability of the closed‐loop system is analysed using Lyapunov's stability theory. Finally, the effectiveness of the proposed design approach is demonstrated by two examples.
Intentional power system islanding under cascading outages using energy function method
Authors: Kamali Sadegh , Amraee Turaj , Khorsand Mojdeh
Published: September 2020

In this study, the ‘where to island’ issue under the transient stability constraints is addressed. Without considering the transient stability, the islanding strategy may fail to stop the propagation of harmful dynamics throughout the network. This study promotes the current available controlled islanding model to handle the transient stability criteria, which is the most important issue during network splitting. Based on the wide area measurements, a two‐stage transient stability constrained network splitting model is developed using a proper transient energy function. In the first stage, the conventional intentional splitting problem is formulated as a mixed‐integer linear programming (MILP) optimisation model with considering operational, coherency and linear AC load flow constraints. The boundary of each island is determined using an optimisation model to achieve the minimum total power imbalance. To assess the transient stability, the network splitting plan obtained from the first stage is then evaluated in the second stage using a transient energy function. In the second stage, to satisfy the transient stability constraint of the critical island, a linear constraint is constructed and added to the MILP formulation of the first stage. In the second stage, the saddle or control unstable equilibrium points are determined using an optimisation model.
Modified virtual synchronous generator based‐primary frequency regulation for renewable generation integrated into power system
Authors: Hu Zhengyang , Gao Bingtuan , Chen Ning , Qu Linan , Peng Chenyu
Published: September 2020

To guarantee the frequency stability of renewable energy sources (RESs) generation integrated into the power system, primary frequency regulation (PFR) for RES generation controlled by virtual synchronous generator (VSG) has been concerned extensively. This study mainly focuses on the dynamic and steady‐state characteristics of VSG in the PFR dead‐band. Based on the typical structure of VSG, small‐signal model of the conventional VSG is established to analyse the issue of the sharp change of angular frequency. Consequently, a novel modified VSG (M‐VSG) controller is proposed, which can ensure a stable angular frequency and synchronise with the grid without the phase‐locked‐loop. The inertia and damping properties of M‐VSG are studied theoretically by eigenvalue analysis, and the design procedure of control parameters is presented. To enhance the practicability, a flexible PFR strategy of M‐VSG is added considering inertia mode, bidirectional mode, and unidirectional mode according to the operation state of RES generation. Moreover, after PFR is added, the proposed controller is analysed with eigenvalue loci to guarantee the stability and dynamic characteristics outside the dead‐band. Finally, hardware‐in‐the‐loop experiment results based on RT‐LAB demonstrate the validity of the theoretical analysis and the superiority of M‐VSG in participating in flexible PFR.
Unbalance mitigation by optimal placement of static transfer switches in low voltage distribution feeders
Authors: Heidari‐Akhijahani Adel , Safdarian Amir , Lehtonen Matti
Published: September 2020

With the rapid proliferation of residential rooftop photovoltaic (PV) systems, current and voltage unbalance issues have become a matter of great concern in low voltage (LV) distribution feeders. To overcome the issues, this study proposes a model to optimally rephase customers and PVs among the three phases via static transfer switches (STSs). The optimal STS placement is also considered in the model to achieve a cost effective solution with optimum number and location of STSs. The objective is to minimise total energy losses caused by current unbalance, minimise the number of STSs, and keep voltage unbalance along the feeder within the acceptable range. The model is solved via a non‐dominated sorting genetic algorithm‐II (NSGA‐II) which provides a Pareto front. A fuzzy decision‐making approach is then applied to choose the final solution among the Pareto front points. The proposed model is simulated on the IEEE 123‐Node Test Feeder. The simulations are conducted in MATLAB where the COM interface capability is used to call OpenDSS to evaluate NSGA‐II populations. According to the achieved results, the proposed model can effectively and affordably apply STSs to mitigate unbalance issues in LV feeders hosting high penetration of rooftop PVs.
Sampled value‐based bus zone protection scheme with dq‐components
Authors: Jena Soumitri , Bhalja Bhavesh R.
Published: September 2020

This study presents a novel algorithm based on dq‐components, which has been effectively used for bus zone protection. The analogue current transformer (CT) secondary signals are acquired and converted into sampled values. Then, the fundamentals of an instantaneous current‐based differential protection scheme (87B) have been considered to establish the trip logic of the proposed scheme. Its performance has been validated by simulating faults on an existing 400‐kV substation with a double‐bus‐single‐breaker configuration. Moreover, a laboratory test bench has been developed to test the authenticity of the proposed scheme for various fault scenarios. The obtained results from the simulation model and laboratory prototype testify the claims of higher sensitivity during internal faults and better stability during external faults with CT saturation. The proposed scheme has been able to provide high‐speed busbar protection against a wide range of internal faults. Comparative evaluation with contemporary busbar protection schemes clearly indicates its superiority.
Enhanced wind turbine generator fault ride‐through capability by using hybrid on‐load tap changer
Authors: Karbouj Hazem , Hussain Rather Zakir
Published: September 2020

Low‐voltage ride‐through (LVRT) compliance of wind energy conversion systems is one of the significant concerns for both the wind industry and the system operator. In this study, power electronic‐assisted on load tap changer (OLTC) is proposed as a pragmatic solution to enhance LVRT performance of wind turbine generator (WTG). Furthermore, a coordinated control strategy between OLTC and WTG controller is proposed to mitigate post‐fault over‐voltage issues that are encountered due to the relatively slow dynamics of hybrid OLTC. The results suggest that employing hybrid OLTC does not only improve LVRT compliance of WTG but also significantly improve voltage dip‐induced delayed active power recovery of WTG.
Identification of critical lines for enhancing disaster resilience of power systems with renewables based on complex network theory
Authors: Zhao Yuxuan , Liu Shengyuan , Lin Zhenzhi , Yang Li , Gao Qiang , Chen Yiwei
Published: September 2020

Natural disasters, such as typhoons and earthquakes, pose great challenges to power system resilience and power supply reliability. It is widely acknowledged that critical transmission lines play a significant role in enhancing the resilience and reliability of power systems under severe natural disasters. In order to improve the disaster resilience of power systems with renewables, a critical line identification approach is proposed in this work based on the complex network theory. Firstly, the concept of core skeleton network (CSN) of power systems with renewables is introduced and a two‐step strategy is presented to optimise the CSNs of the concerned power system considering the variable outputs of renewables. Then, a statistical salience method incorporating edge salience and the state‐of‐the‐art null model in complex network theory is proposed to identify critical lines of each CSN and the concerned power system with renewables. Finally, the effectiveness of the proposed critical lines identification approach is verified by simulations on the modified IEEE 118‐bus system with renewables, Guangdong Provincial Power System (GPPS) and Zhejiang Provincial Power System (ZPPS) in China. Simulation results show that by using the proposed approach, the critical transmission lines can be effectively identified, not requiring a predefined number of critical lines.
Ion flow field modelling based on lattice Boltzmann method and its mesh refinement
Authors: Zhu Ting , Wang Song , Zhang Naming , Wang Shuhong , Ning Shuya
Published: September 2020

Ion flow is a phenomenon that exists in the normal operation of high‐voltage direct current (HVDC) transmission lines. It will increase the electric field below the wire and poses a threat to the life and health of humans. Hence ion flow is considered in the HVDC transmission line laying design as a significant factor. However, the control equation of this phenomenon is a form of convective dominance, and it is easy to cause oscillation for its solution. In this study, a mesoscopic approach, the lattice Boltzmann method (LBM), is first proposed to solve the ion flow field. Firstly, the control equation of the ion flow field is rewritten in the form of the lattice Boltzmann equation. Secondly, reducing the computation load of the model by using local mesh refinement. Then a new mesh refinement method based on distribution function is proposed and compared with several other methods. Thirdly, the analytical solutions of the coaxial cylinder model are compared with LBM results, and a measuring platform is set up also for verification. Finally, the three‐layer grid is successfully applied in an 800 kV unipolar full‐scale transmission line.
Top‐oil temperature modelling by calibrating oil time constant for an oil natural air natural distribution transformer
Authors: Wang Lujia , Zhang Xiang , Villarroel Rafael , Liu Qiang , Wang Zhongdong , Zhou Lijun
Published: September 2020

Integration of low carbon technologies poses a technical challenge on distribution transformers due to the dynamic loading and potentially frequent overloading scenarios. Transformer dynamic thermal rating is hence required, which is the most economical approach to tackle this challenge and ensure a safe operation. To reach the aim, it is important to enhance the accuracy of the dynamic thermal model, where the top‐oil temperature is a key thermal parameter. In this study, a wide range of constant load temperature‐rise tests were carried out on an 11/0.433 kV distribution transformer to study the dynamic thermal behaviour of the top‐oil temperature. A model based on the IEC 60076‐7 thermal model but with an improved oil time constant calibration was deduced for top‐oil temperature modelling. The oil time constant calibration was inspired by IEEE C57.91 and verified by eight temperature‐rise tests with load factors ranging from 0.7 to 1.4 pu. In addition, the improved top‐oil temperature modelling was further verified in experiments under multiple load profiles.