bluuebunny/crossref_metadata_2025 huggingface dataset:
Gastric cancer incidence and mortality trends 2007–2016 in three European countries
Authors: Libânio Diogo , Rodrigues Jessica R. , Bento Maria J. , Ebigbo Alanna , Messman Helmut , Verhoeven Rob H.A. , Van Damme Nancy , Bisschops Raf , Spaander Manon C.W. , Dinis-Ribeiro Marío
Published: October 2021

Background Increased awareness of gastric cancer risk, easy access to upper endoscopy, and high definition endoscopes with virtual chromoendoscopy may have led to the increase in early diagnosis of gastric cancer observed in recent years in Europe, which may be associated with improved survival. Currently, no data exist on the impact of early diagnosis on survival at a populational level in Europe. Our aim was to assess gastric cancer incidence, early diagnosis, and survival in northwestern and southern European countries with a low-to-moderate incidence of gastric cancer.

Methods Data on 41 138 gastric cancers diagnosed in 2007–2016 were retrieved from national cancer registries of Belgium, the Netherlands, and northern Portugal. Age-standardized incidence and mortality rates were assessed and expressed per 100 000 person-years. Early diagnosis was defined as T1 tumors. Net survival estimates for 2007–2011 vs. 2012–2016 were compared.

Results Age-standardized incidence and mortality decreased over time in Belgium, northern Portugal, and the Netherlands (relative incidence decrease 8.6 %, 4.5 %, and 46.8 %, respectively; relative mortality decrease 22.0 %, 30.9 %, and 50.0 %, respectively). Early gastric cancer diagnosis increased over time for all countries. Net 1-year survival improved significantly between the two time periods in all countries, and at 5 years in Belgium and Portugal.

Conclusions This is the first study comparing trends (2007–2016) in gastric cancer incidence and mortality in some European countries. We found an increasing proportion of T1 gastric cancers and a decrease in age-standardized mortality over time, supporting the use of secondary prevention strategies.
[1,3]-Dithiolo-[4,5-d][1,3-dithiole]-2,5-dione
Authors: Müller Harald , Bourcet Léa
Published: October 2021

A safe, three-step reaction sequence to [1,3]-dithiolo-[4,5-d][1,3-dithiole]-2,5-dione starting from carbon disulfide is presented. Optimized reaction conditions, rigorous purification, and full characterization of all intermediates provide reproducibly a final product of superior quality with a melting point of 181 °C (dec.).
Homeopathy for COVID-19 Prevention: Report of an Intervention at a Brazilian Service Sector Company
Authors: Daruiche Paulo Sergio Jordão , Canoas Walter Swain , Figueira Katya Aparecida Gonçalves , Peres Giovani Bravin
Published: October 2021

Background COVID-19 quickly became a serious public health problem worldwide, with serious economic and social repercussions. Homeopaths around the world have been studying to find a genus epidemicus (GE) medicine that might help in the prevention and treatment of this disease.

Objective To compare the incidence of COVID-19 between employees who received or did not receive a homeopathic GE medicine for disease prevention.

Methods Retrospective cohort analysis. The study population comprised all employees of a service sector company in São Paulo, Brazil, and followed up by the corporate Occupational Health department. Intervention consisted of administering Arsenicum album 30cH in a one-weekly dose. Primary outcome was incidence of COVID-19 during 3-months' follow-up (April to July, 2020).

Results We analyzed 1,642 of 1,703 employees without previous diagnosis of COVID-19 at onset of the study period: 53.34% of employees were referred to telework at home and did not receive intervention (Group 1, G1); 24.66% remained working on-premises in the state of São Paulo and received the intervention (Group 2, G2); 21.98% remained working on company premises in other states and did not receive intervention (Group 3, G3). Incidence rate of COVID-19 was respectively 13.35%, 0.74%, and 67.87% (p < 0.001). The odds ratio of being infected in (1) G3 versus G1 was 13.70 (95% confidence interval [CI], 10.21 to 18.39), (2) G3 versus G2 was 283.02 (95% CI, 88.98 to 900.18), and (3) G1 versus G2 was 20.66 (95% CI, 6.53 to 65.39).

Limitations The present is a retrospective analysis of a real-world experience. We could not ensure direct observed treatment, and neither could we control adherence to general prevention measures outside company premises.

Conclusion The incidence of COVID-19 was significantly lower amongst on-premises employees who received the GE medication in comparison to workers who did not receive the intervention (those either at other company premises or teleworking at home).
Left Main Coronary Artery Spasm: Case Report
Authors: Bodicherla Vijay Kumar , Srikakulapu Srikrishna , Nemani Lalitha
Published: October 2021

Vasospasm of coronary artery is a well-known cause for acute coronary syndrome (ACS) but left main coronary artery (LMCA) spasm is very rare. It may be iatrogenic or spontaneous. Here we report a case of a 44-year-old female who presented with chronic stable angina and experienced LMCA vasospasm while undergoing coronary angiography.
Toe Walking as the Initial Symptom of a Spinocerebellar Ataxia 13 in a Patient Presenting with a Mutation in the KCNC3 Gene
Authors: Pomarino David , Thren Johanna Ronja , Thren Anneke , Rostasy Kevin , Schoenfeldt Jan
Published: October 2021

This article at hand described a 4-year-old child patient who initially presented with the symptoms of toe walking. As part of the diagnostic process, the patient was genetically tested to find the cause of the gait anomaly. The genetic test found a mutation in the KCNC3 gene. The variant c.1268G > A; p.Arg423. His was found in a heterozygotic state. This variant is frequently described as a cause for spinocerebellar ataxia type 13 (SCA13) in the literature. Apart from toe walking as the most pronounced symptom, the patient displayed an instable gait with frequent falls and delayed speech development. The genetic test to determine the cause of the gait anomaly successfully diagnosed the patient with a previously undiscovered SCA13 and subsequently enabled the recommendation of personalized further treatment.
Data-driven modeling reveals the Western dominance of global public interest in earthquakes
Authors: Kam Jonghun , Park Jihun , Shao Wanyun , Song Junho , Kim Jinhee , Gizzi Fabrizio Terenzio , Porrini Donatella , Suh Young-Joo
Published: October 2021

Catastrophic earthquakes stimulate information-seeking behaviors beyond the affected geographical boundaries; however, our understanding of the dynamics of global public interest in earthquakes remains limited. Herein, we harness Big Data to examine the dynamic patterns of global public interest, concerning 17 significant worldwide earthquakes over 2004–2019. We find that the global community shows a higher level of interest when an earthquake occurs in developed countries than in developing countries; however, they lose their interest in the former more rapidly than the latter. Regardless of the affected nation, there is a one- to two-week “golden” time window when attention can be leveraged for fundraising and humanitarian aid. Our findings suggest that European citizens who are highly interested in earthquakes emerge as a potential key community to achieve great inclusiveness in policy interventions to solicit international aid. The findings of this study hint at how Big Data can be utilized to identify “time windows of opportunities” for international humanitarian organizations to efficiently raise donations, charities, and aid resources around the world.
Quasi-classical trajectory investigation of H + SO2 → OH +
SO reaction on full-dimensional accurate potential energy surface
Authors: Qin Jie , Li Jia , Li Jun
Published: October 2021

The reaction H+SO2→OH+SO is important in the combustion and atmospheric chemistry, as well as the interstellar medium. It also represents a typical complex-forming reaction with deep complexes, serving as an ideal candidate for testing various kinetics theories and providing interesting reaction dynamical phenomena. In this work, we reported a quasi-classical trajectory study of this reaction on our previously developed accurate full-dimensional potential energy surface. The experimental thermal rate coefficients over the temperature range 1400 K≤T≤2200 K were well reproduced. For the reactant SO2 being sampled at the ground ro-vibrational state, the calculated integral cross sections increased slightly along the collision energy ranging from 31.0 kcal/mol to 40.0 kcal/mol, and then became essentially flat at the collision energy within 40.0−55.0 kcal/mol. The product angular distributions are almost symmetric with nearly identical backward-forward double peak structure. The products OH and SO vibrational state distributions were also analyzed.
Direct observation of electron-vibration coupling at MXene-solvent
interface
Authors: Xu Yan-jun , Liu He-yuan , Chen Hai-long
Published: October 2021

MXenes, a new family of two-dimensional (2D) materials, have received extensive interest due to their fascinating physicochemical properties, such as outstanding light-to-heat conversion efficiency. However, the photothermal conversion mechanism of MXenes is still poorly understood. Here, by using femtosecond visible and mid-infrared transient absorption spectroscopy, the electronic energy dissipation dynamics of MXene (Ti3C2Tx) nanosheets dispersed in various solvents are carefully studied. Our results indicate that the lifetime of photoexcited MXene is strongly dependent on the surrounding environment. Especially, the interfacial electron-vibration coupling between the MXene nanosheets and the adjacent solvent molecules is directly observed following the ultrafast photoexcitation of MXene. It suggests that the interfacial interactions at the MXene-solvent interface play a critical role in the ultrafast energy transport dynamics of MXene, which offers a potentially feasible route for tailoring the light conversion properties of 2D systems.
How charge trapping affects the conductivity of electrochemically doped poly(3-hexylthiophene) films
Authors: Hornberger Lea-Sophie , Neusser David , Malacrida Claudia , Kaake Loren G. , Ludwigs Sabine
Published: October 2021

Electrochemical doping is an elegant method of controlling the doping level and charge carrier densities of conjugated polymer films and enhancing their thermoelectric figure of merit. Applying this doping technique to films of poly(3-hexylthiophene) (P3HT) results in conductivities with values as high as 200 S/cm. The stability of the doped films in the solid state can be probed by UV-vis-NIR spectroscopy. We found that the choice of the conducting salt in the liquid electrolyte exerts a strong influence over the conductivity. Using TBAPF6 and LiClO4 provides highest conductivities for P3HT films, while LiTFSI and TBABF4 show overall lower performance. This effect is also reflected in cyclic voltammetry measurements coupled with in situ spectroscopy. Overall lower reversibility upon multiplex cycling in LiTFSI and TBABF4 electrolytes suggests strong charge trapping effects, which one might attribute to a considerable fraction of charges (holes/ions) remaining in the films after charge/discharge cycles. The salts with stronger charge irreversibility in the electrochemistry experiments show the poorer solid state conductivities. Our conclusion is that one should carefully choose the electrolyte to ensure good percolation pathways and delocalized charge transport throughout doped films.
An algebraic interpretation of the intertwining operators associated with the discrete Fourier transform
Authors: Atakishiyeva Mesuma , Atakishiyev Natig , Zhedanov Alexei
Published: October 2021

We show that intertwining operators for the discrete Fourier transform form a cubic algebra Cq, with q being a root of unity. This algebra is intimately related to the other two well-known realizations of the cubic algebra: the Askey–Wilson algebra and the Askey–Wilson–Heun algebra.
Theoretical considerations of superconducting HfBH2 and HfB2H under high pressure
Authors: Zhao Yaping , Zhang Xiaohua , Liu Yong , Yang Guochun
Published: October 2021

AlB2-type metal diborides represented by MgB2 become an important type of conventional superconductors. However, AlB2-type HfB2 is not superconductive. Pressure-induced HfH10 are predicted to be high-temperature superconductors. Here, first-principles swarm-intelligence structural search calculations identified two ternary compounds, HfBH2 and HfB2H, showing superconductivity with the predicted superconducting transition temperatures of 2.1–14.9 and 2.2–15.0 K for a wide range of Coulomb pseudopotential μ* = 0.15–0.05 at 300 GPa, respectively. The two compounds exhibit interesting structural features, such as an Hf–H layer, covalent B–H framework, and graphene-type boron layer, as observed in AlB2-type HfB2. Besides atomic hydrogen and covalent skeleton contributing to superconducting transition, H-activated hafnium also plays a certain role.
Facet controlled anisotropic magnons in Y3Fe5O12 thin films
Authors: Medwal Rohit , Deka Angshuman , Vas Joseph Vimal , Duchamp Martial , Asada Hironori , Gupta Surbhi , Fukuma Yasuhiro , Rawat Rajdeep Singh
Published: October 2021

Directional specific control on the generation and propagation of magnons is essential for designing future magnon-based logic and memory devices for low power computing. The epitaxy of the ferromagnetic thin film is expected to facilitate anisotropic linewidths, which depend on the crystal cut and the orientation of the thin film. Here, we have shown the growth-induced magneto-crystalline anisotropy in 40 nm epitaxial yttrium iron garnet (YIG) thin films, which facilitate cubic and uniaxial in-plane anisotropy in the resonance field and linewidth using ferromagnetic resonance measurements. The growth-induced cubic and non-cubic anisotropy in epitaxial YIG thin films are explained using the short-range ordering of the Fe3+ cation pairs in octahedral and tetrahedral sublattices with respect to the crystal growth directions. This site-preferred directional anisotropy enables an anisotropic magnon–magnon interaction and opens an avenue to precisely control the propagation of magnonic current for spin-transfer logics using YIG-based magnonic technology.
Three-dimensional metal–semiconductor–metal bipolar ultraviolet phototransistor based on GaN p-i-n epilayer
Authors: Jiang Ke , Sun Xiaojuan , Chen Yuxuan , Zhang Shanli , Ben Jianwei , Chen Yang , Zhang Zi-Hui , Jia Yuping , Shi Zhiming , Li Dabing
Published: October 2021

GaN-based ultraviolet (UV) detectors have a considerable application potential in many fields. In this Letter, we report an alternative strategy to realize a high-optical-gain bipolar UV phototransistor based solely on a GaN p-i-n epilayer. The device consists of two tightly adjacent vertical p-i-n structures with a common n-type layer as a floating base. The collector and emitter electrodes are deposited on the two p-type mesas, forming a three-dimensional metal–semiconductor–metal (MSM) like photodetector. As a result, a peak responsivity of 11.7 A/W at a wavelength of 358 nm at 5 V is realized, corresponding to an optical gain of 40 with the assumption of 100% internal quantum efficiency. Different from traditional GaN-based n-p-i-n phototransistors, the optical gain of this detector originates from the accumulated electrons in the n-type floating base upon illumination, which can lower the barrier height between the base and emitter, leading to hole emission from the emitter. Although the structure of this phototransistor is similar to a planar back-to-back Schottky-type MSM photodetector, the response speed is much faster because the gain mainly results from carrier emission rather than MS interface defects.
Pore-resolved volume-of-fluid simulations of two-phase flow in porous media: Pore-scale flow mechanisms and regime map
Authors: Ambekar Aniket S. , Mondal Sujoy , Buwa Vivek V.
Published: October 2021

Two-phase flow through porous media is important to the development of secondary and tertiary oil recovery. In the present work, we have simulated oil recovery through a pore-resolved three-dimensional medium using volume-of-fluid method. The effects of wettability and interfacial tension (IFT) on two-phase flow mechanisms are investigated using pore-scale events, oil-phase morphology, forces acting on oil ganglia surfaces, and oil recovery curves, for Capillary numbers (Ca) in the range of 1.2 × 10−3 to 6 × 10−1. We found that the two-phase flow through oil-wet medium is governed by pore-by-pore filling mechanism dominated by the Haines-jumps. At low Ca values, a change in the wettability from oil- to neutrally wet resulted into the change of pore-by-pore filling mechanism to co-operative pore filling and as the medium wettability changes from the neutrally to the weakly water-wet, the corner flow events begin to emerge. At low Ca values, the invasion through weakly water-wet porous medium is dominated by co-operative filling and results into an increased oil recovery, whereas the two-phase flow through strongly water-wet medium is governed by corner flow events resulting in a low oil recovery. The corner flow events are found to be a function of not only the medium wettability, but also of Ca and are a characteristic of controlled imbibition. Further, we show that a substantial decrease in the IFT results in a fingerlike invasion at pore-scale, irrespective of the medium wettability. Finally, a two-phase flow regime map is proposed in terms of Ca and contact angle based on the two-phase interface morphology.
Temperature-dependent and nonlinear optical response of double perovskite Cs2AgBiBr6 nanocrystals
Authors: Zhang Ye , Wang Quan , Sui Ning , Kang Zhihui , Li Xianfeng , Zhang Han-zhuang , Zhang Jiaqi , Wang Yinghui
Published: October 2021

Cs2AgBiBr6 double perovskite nanocrystals (NCs) are materials within the halide perovskite family with promising application potential, owing to their nontoxicity and excellent stability. Herein, Cs2AgBiBr6 NCs were synthesized and their photo-physical properties were investigated in detail. The temperature-dependent photoluminescence (PL) test confirms that their PL mechanism is dependent on the competition between the PL originating from carrier recombination in the conduction band and that in the self-trapping states. Their carrier recombination constants (involving the monomolecular, bimolecular, and Auger recombination rate constants) were obtained from transient absorption data and indicated that the monomolecular recombination decreases with the lowering of temperature, while the bimolecular and Auger recombination show opposite trends. The nonlinear optical properties were studied based on the Z-scan technique, with a two-photon absorption cross section of approximately 1906 GM. Our results suggest that Cs2AgBiBr6 NCs can be extensively applied in the field of optoelectronics, and conventional electronic switches will benefit from the excellent carrier dynamics and nonlinear optical properties.
Electric-field induced phase transitions in capillary electrophoretic systems
Authors: Kaygusuz Hakan , Erim F. Bedia , Berker A. Nihat
Published: October 2021

The movement of particles in a capillary electrophoretic system under electroosmotic flow was modeled using Monte Carlo simulation with the Metropolis algorithm. Two different cases with repulsive and attractive interactions between molecules were taken into consideration. Simulation was done using a spin-like system, where the interactions between the nearest and second closest neighbors were considered in two separate steps of the modeling study. A total of 20 different cases with different rates of interactions for both repulsive and attractive interactions were modeled. The movement of the particles through the capillary is defined as current. At a low interaction level between molecules, a regular electroosmotic flow is obtained; on the other hand, with increasing interactions between molecules, the current shows a phase transition behavior. The results also show that a modular electroosmotic flow can be obtained for separations by tuning the ratio between molecular interactions and electric field strength.
Proton irradiation induced chemical ordering in an Al0.3CoFeNi high entropy alloy
Authors: Dasari Sriswaroop , Sharma Abhishek , Byers Todd A. , Glass Gary A. , Srivilliputhur Srinivasan , Rout Bibhudutta , Banerjee Rajarshi
Published: October 2021

The radiation resistance of single-phase high entropy alloys has been reported to be superior to conventional alloys, due to their high lattice distortion and sluggish diffusion kinetics. The current study combines the beneficial effects of a concentrated multi-component solid solution and chemical ordering on the parent lattice of a candidate alloy, Al0.3CoFeNi, to enhance proton radiation resistance. The strong ordering tendency in this alloy results in the formation of Ni-Al-rich short-range ordered (SRO) domains when it is annealed in a single FCC phase field and water quenched. The irradiation of these microstructures with high-fluence MeV-energetic protons aids the transformation of the prior metastable single FCC solid-solution with SRO domains toward a more stable condition with L12 long-range ordered (LRO) domains embedded within the FCC solid solution matrix. Potentially, the creation of radiation-induced vacancy cascades within the FCC solid-solution enhances local diffusivity aiding the transition from SRO domains to LRO L12 domains. Therefore, this can be considered as a recovery mechanism, since the radiation-induced damage is not allowed to accumulate and is minimized via nanometer-scale precipitation of the ordered intermetallic phase. Additionally, preferential Co segregation to defect clusters or dislocation loops was also observed. In comparison, purely thermal activation via annealing at 500 °C for 30 min induces a similar transformation from SRO to LRO in this alloy, driving the system closer to equilibrium.
Sustainable targeted interventions to mitigate the COVID-19 pandemic: A big data-driven modeling study in Hong Kong
Authors: Zhou Hanchu , Zhang Qingpeng , Cao Zhidong , Huang Helai , Dajun Zeng Daniel
Published: October 2021

Nonpharmaceutical interventions (NPIs) for contact suppression have been widely used worldwide, which impose harmful burdens on the well-being of populations and the local economy. The evaluation of alternative NPIs is needed to confront the pandemic with less disruption. By harnessing human mobility data, we develop an agent-based model that can evaluate the efficacies of NPIs with individualized mobility simulations. Based on the model, we propose data-driven targeted interventions to mitigate the COVID-19 pandemic in Hong Kong without city-wide NPIs. We develop a data-driven agent-based model for 7.55×106 Hong Kong residents to evaluate the efficacies of various NPIs in the first 80 days of the initial outbreak. The entire territory of Hong Kong has been split into 4905 500×500m2 grids. The model can simulate detailed agent interactions based on the demographics data, public facilities and functional buildings, transportation systems, and travel patterns. The general daily human mobility patterns are adopted from Google’s Community Mobility Report. The scenario without any NPIs is set as the baseline. By simulating the epidemic progression and human movement at the individual level, we propose model-driven targeted interventions which focus on the surgical testing and quarantine of only a small portion of regions instead of enforcing NPIs in the whole city. The effectiveness of common NPIs and the proposed targeted interventions are evaluated by 100 extensive simulations. The proposed model can inform targeted interventions, which are able to effectively contain the COVID-19 outbreak with much lower disruption of the city. It represents a promising approach to sustainable NPIs to help us revive the economy of the city and the world.
Decisive conditions for strategic vaccination against SARS-CoV-2
Authors: Böttcher Lucas , Nagler Jan
Published: October 2021

While vaccines against severe acute respiratory syndrome coronavirus (SARS-CoV-2) are being administered, in many countries it may still take months until their supply can meet demand. The majority of available vaccines elicit strong immune responses when administered as prime-boost regimens. Since the immunological response to the first (“prime”) dose may provide already a substantial reduction in infectiousness and protection against severe disease, it may be more effective—under certain immunological and epidemiological conditions—to vaccinate as many people as possible with only one dose instead of administering a person a second (“booster”) dose. Such a vaccination campaign may help to more effectively slow down the spread of SARS-CoV-2 and reduce hospitalizations and fatalities. The conditions that make prime-first vaccination favorable over prime-boost campaigns, however, are not well understood. By combining epidemiological modeling, random-sampling techniques, and decision tree learning, we find that prime-first vaccination is robustly favored over prime-boost vaccination campaigns even for low single-dose efficacies. For epidemiological parameters that describe the spread of coronavirus disease 2019 (COVID-19), recent data on new variants included, we show that the difference between prime-boost and single-shot waning rates is the only discriminative threshold, falling in the narrow range of 0.01–0.02 day−1 below which prime-first vaccination should be considered.
TeraFET terahertz detectors with spatially non-uniform gate capacitances
Authors: Zhang Yuhui , Shur Michael S.
Published: October 2021

A non-uniform capacitance profile in the channel of a terahertz (THz) field-effect transistor (TeraFET) could improve the THz detection performance. The analytical solutions and simulations of the hydrodynamic equations for the exponentially varying capacitance vs distance showed ∼10% increase in the responsivity for the 130 nm Si TeraFETs in good agreement with numerical simulations. Using the numerical solutions of the hydrodynamic equations, we compared three different Cg configurations (exponential, linear, and sawtooth). The simulations showed that the sawtooth configuration provides the largest response tunability. We also compared the effects of the non-uniform capacitance profiles for Si, III–V, and p-diamond TeraFETs. The results confirmed a great potential of p-diamond for THz applications. Varying the threshold voltage across the channel could have an effect similar to that of varying the gate-to-channel capacitance. The physics behind the demonstrated improvement in THz detection performance is related to the amplification of boundary asymmetry by the non-uniform device geometry.
Use of voluntary environmental contracts for wetland governance in the European Mediterranean region
Authors: Ernoul Lisa , Vera Pablo , Gusmaroli Giancarlo , Muccitelli Serena , Pozzi Carolina , Magaudda Stefano , Polajnar Horvat Katarina , Smrekar Aleš , Satta Alessio , Monti Flavio
Published: October 2021

Ramsar sites are internationally protected wetlands designated to maintain an international network for biodiversity conservation and sustain human life. There are often conflicting interests for site management that lead to decisions based on sectoral policies or local approaches that have poor outcomes in terms of effectiveness and trade-offs. The European Water Framework Directive (2000/60/EC) requires European countries to foster an integrated approach for wetland management through collaborative governance processes. The environmental contract is a tool that has been developed and implemented to set the ground for voluntary-based commitments for the sustainable governance of water systems. This paper reports on the results of the first study investigating the implementation of voluntary environmental contracts at the Mediterranean European level. Our results indicate that Ramsar sites in the region have made great progress with the development of management plans, yet many sites still lack governance schemes involving stakeholders. Voluntary environmental contracts have been widely used in Ramsar sites in France and Italy, but only a few other European countries have started implementing them. We have identified the need to further adapt the tool to local and national contexts, as well as the need for legislation, to promote upscaling at the regional scale.
Soil moisture impacts nitrification from nitrogen fertilisers treated with 3,4-dimethylpyrazole phosphate in acidic soils
Authors: Kaveney Brooke , Condon Jason , Doran Gregory , Galea Francesca , Rigg Jessica
Published: October 2021

Context Success of the nitrification inhibitor 3,4-dimethylpyrazole phosphate (DMPP) is dependent on a range of soil factors including pH and soil organic carbon (OC) content. Aims This study identified the effect of soil properties and moisture content at the time of DMPP application on the efficiency of DMPP and soil mineral N concentrations. Methods Soil was collected from paired paddocks with contrasting management, cropping or pasture across three sites. Soil samples were pre-incubated for 7 days with moist (−85 kPa) or air dried soil to simulate sowing into soil with moisture equivalents of post seasonal break or dry sowing. Urea ammonium nitrate (UAN) was applied with and without DMPP to all soils. Key results DMPP inhibited nitrification in all soils, although decreased inhibitory effectiveness was observed in acidic soils compared to neutral soils. Inhibition efficacy on acidic soils was improved when DMPP was applied to dry rather than wet soils. Neutral soils did not observe the same soil moisture effect having similar inhibition efficiency of DMPP observed between dry and wet soil application. Nitrogen fertilisers applied to dry soils nitrified at a greater rate than when applied to wet soils. DMPP decreased the ammonia oxidising bacteria (AOB) population while the ammonia oxidising archaea (AOA) amoA gene copy numbers were unaffected. Conclusions This study shows that the lower soil pH and high OC contents can reduce the efficacy of DMPP. Implications When using DMPP in Australian broad acre agriculture, knowledge of soil properties including soil pH will determine if application of DMPP is suitable for use before or after a seasonal break rainfall event.
Importance of impedance spectroscopy in self-assembled monolayer-based large-area tunnel junctions
Authors: Francis Jaismon , Bassam S A , Sangeeth C S Suchand
Published: October 2021

Two-terminal direct current (DC) measurements are generally used for the electrical characterization of self-assembled monolayer (SAM)-based large-area tunnel junctions. In DC measurements, the total current through the molecular junction is measured and it is thus impossible to separate molecular effects from interface effects. The charge transport parameters are derived indirectly from the current–voltage relationship. For instance, contact resistance at the interface between the electrode and SAMs is estimated by extrapolating the resistance versus chain length curve. On the other hand, through impedance spectroscopy along with equivalent circuit modelling, each component of the junction can be determined. This paper compares the contact resistance values estimated using both DC and impedance spectroscopic data of alkanethiolate SAM-based molecular junctions reported previously. We show that in the case of molecular tunnel junctions with a resistive protective layer (PL), the widely used DC measurements alone fail to show the actual molecular behaviour of the junction as the charge transport through the junction is dominated by the PL itself. We also show that contact resistance estimated from the DC measurements on defective SAM junctions can be wrong and leads to the incorrect transport mechanism, while the impedance measurements estimate the actual values of contact resistance and identify the bottlenecks in charge transport through such a defective molecular junction.
Ion trapping model of the ac conductivity in disordered solids
Authors: Khamzin A A , Nikitin A S
Published: October 2021

In this paper, we develop an approach based on ions trapping to describe the conductivity spectra in disordered solids. Applying the multiple trapping model and the diffusion equation for ions, we obtained a new expression for the ac conductivity, which allows us to describe the conductivity spectra in wide ranges of frequencies and temperatures. In the high-temperature region, the new expression for the ac conductivity reproduces the Jonscher behavior, and with decreasing temperatures transforms into an expression of the NCL-type. A new expression for the ac conductivity was successfully tested on the conductivity spectra of ion-conducting glasses.
Robust gas recognition with mixed interference using a spiking neural network
Authors: Peng Cheng , Zheng Yangong
Published: October 2021

Spiking neural networks (SNNs) have attracted significant interest owing to their high computing efficiency. However, few studies have focused on the robustness of SNNs and their application to electronic noses for gas recognition under strong interference. The goal of this study was to explore the robustness of a SNN for gas recognition under mixed interference. Data on mixed gases with different levels of interference were simulated by fitting experimental data. Two layers of a SNN based on leaky integrate-and-fire (LIF) neurons were constructed and the network was trained solely on datasets of pure targeted gases. Testing was then performed using data with mixed interference. The SNN achieved superior performance compared to other algorithms and remained 100% accurate for gas recognition up to a 10% interference ratio. The interval distance of spiking times between classes represents the robust capacity of the SNN according to the algorithm of the LIF neurons. SNNs have excellent capacity to maximize the differences between data of different classes and are promising candidates for electronic noses.
In-situ electrochemical polymerization of aniline on flexible conductive substrates for supercapacitors and non-enzymatic ascorbic acid sensors
Authors: Liu Hui , Tao You , Sun Huijuan , Wang Tian-Xiong , Peng Zhisheng , Jin Jiyou , Wang Zhongpu , Peng Kang , Wei Haonan , Li Yong Jun , Han Bao-Hang , Sun Lianfeng
Published: October 2021

Polyaniline, as a kind of conductive polymer with commercial application prospects, is still under researches in its synthesis and applications. In this work, polyaniline was fabricated on flexible substrates including carbon cloths and polyethylene naphthalate by in situ electropolymerization method. The synthesized flexible electrodes were characterized by scanning electron microscopy, High resolution transmission electron microscope, atomic force microscope, Fourier transform infrared, x-ray diffraction, and x-ray photoelectron spectroscopy. Owing to the conductivity and the reversible redox property, the polyaniline/carbon cloth electrodes show excellent properties such as decent supercapacitor performance and good detection capability toward ascorbic acid. As supercapacitors, the electrodes exhibit a specific capacitance as high as 776 F g–1 at a current density of 1 A g–1 and a long cycle life of 20 000 times in the three-electrode system. As ascorbic acid sensors, the flexible electrodes demonstrate stable response to ascorbic acid in the range of 1–3000 μM with an outstanding sensitivity (4228 μA mM–1 cm–2), low detection limit (1 μM), and a fast response time. This work holds promise for high-performance and low-cost flexible electrodes for both supercapacitors and non-enzymatic ascorbic acid sensors, and may inspire inventions of self-powered electrochemical sensor.
Energy estimates and convergence of weak solutions of the porous medium equation
Authors: De Paula R , Gonçalves P , Neumann A
Published: October 2021

We study the convergence of the weak solution of the porous medium equation with a type of Robin boundary conditions, by tuning a parameter either to zero or to infinity. The convergence is in the strong sense, with respect to the L
2-norm, and the limiting function solves the same equation with Neumann (resp. Dirichlet) boundary conditions when the parameter is taken to zero (resp. infinity). Our approach is to consider an underlying microscopic dynamics whose space–time evolution of the density is ruled by the solution of those equations and from this, we derive sufficiently strong energy estimates which are the keystone to the proof of our convergence result.
High-performance voltage controlled multilevel MRAM cell
Authors: Nisar Arshid , Dhull Seema , Kaushik Brajesh Kumar , Mittal Sparsh
Published: October 2021

In the recent past, spin-transfer torque (STT) and spin-orbit torque (SOT) based magnetic random access memories (MRAMs) have been studied for future energy efficient and non-volatile memory applications. Multilevel cell (MLC) design has emerged as one of the promising solutions to enhance the storage density of these MRAMs. However, the conventional MLC design adds a larger magnetic tunnel junction (MTJ) stack that makes it difficult to maintain low switching current and high speed. Moreover, it becomes very difficult to reduce the driver transistor size. This paper describes the application of voltage controlled magnetic anisotropy effect to design energy efficient and fast MLC MRAM cell. So far, this approach has been reported only in single-bit MTJ devices. In the proposed MLC the voltage control is able to reduce both SOT and STT switching currents. The results show that the voltage control in MLC enhances energy efficiency and switching speed by more than 80 times and 3 times, respectively, in comparison to conventional SOT based MLCs. The reduction in switching currents also achieves smaller transistor size and enhances area efficiency by 3.5% as compared to conventional SOT-MLC. The effect of different channel materials on SOT switching current has also been explored. Furthermore, the system level evaluation shows that voltage controlled MLC outperforms STT-MRAM and SOT-MRAM for designing cache memory.
The flexible bandpass filter on polyimide substrate for wireless communications systems
Authors: Gong Junshuai , Wang Zhiliang , Qu Huiwen , Cang Dingyong
Published: October 2021

A coplanar waveguide flexible filter based on the polyimide substrate was fabricated by self-metallization technology. The measured results indicate that the central frequency of the proposed filter is 2.5 GHz, the minimum insertion loss is −0.71 dB and the return loss is better than −20 dB. To test the conformal characteristics of the filter, bending and folding tests were performed. The test results show that the measured and simulated results are basically the same when the filter is bent and folded. The flexible filter fabricated by self-metallization technology is expected to be one of the components of future flexible wireless communication systems.
Design and optimization of isotropic stretchable strain sensors for multidirectional monitoring
Authors: Wang Guishan , Liu Ying , Xu Fangsong , Liu Guanjun , Qiu Jing
Published: October 2021

Multidirectional monitoring is highly expectable for stretchable strain sensors by which the randomly orientated cracks or the maximum strain of all directions need to be accommodated. Many current types of research exploit laminated sensors and rosette designs to obtain the desired behavior in several discrete directions. However, this can lead to complex fabricating and resolving processes, as well as significant measurement errors. Our work proposes an isotropic stretchable strain (ISS) sensor that utilizes the in-plane curved sensing film from graphene/silver nanowires (AgNWs), which exhibits uniform sensitivity in all directions within 30∘ and the potential extending to 360∘. The ISS sensor, whose curved shape is optimized based on splines and the quantitative sensing model, is fabricated by a flash stamp machine and followed by vacuum filtration. Experimental results show that the ISS sensor possesses equivalent sensing properties in 30∘ with excellent linearity and durability. Thus our customized sensor is applied to multidirectionally monitor the stretchable surface without consideration for the sensor orientation and the resolving process. Most importantly, the ISS sensor and its design method provide an efficient route for future sensor design with expected properties, not limited to isotropy.
Toward discovering low-lying P-wave excited Σ
c
baryon states *
Authors: Wang Kai-Lei , Zhong Xian-Hui
Published: October 2021

In this study, by combining the equal spacing rule with recent observations of

and

baryons, we predict the spectrum of the low-lying

-mode

-wave excited

states. Furthermore, their strong decay properties are predicted using the chiral quark model and the nature of

is investigated by analyzing the

invariant mass spectrum. The

structure observed in the

mass spectrum was found to potentially arise from two overlapping

-wave

resonances,

and

. These resonances have similar decay widths of

MeV and predominantly decay into the

channel. The

state is likely to be a very narrow state with a width of

MeV, with its decays almost saturated by the

channel. Additionally, evidence of the

resonance as a very narrow peak may be seen in the

invariant mass spectrum. The other two

-wave states,

and

, are relatively narrow states with similar widths of

MeV and predominantly decay into

and

, respectively. This study can provide useful references for discovering these low-lying

-wave states in forthcoming experiments.
Case Study on the γ-algorithm: Possible Tests from the Luminosity versus Displacement Correlation of High Mass X-Ray Binaries
Authors: Zuo Zhao-Yu , Zhang Huan
Published: October 2021

Using the apparent correlation of luminosity (L
X) versus displacement (R) of high mass X-ray binaries (HMXBs), we aim to constrain the common envelope (CE) mechanism, which is vital in the formation and evolution of compact binaries. We find that under the assumption of the γ-algorithm, the apparent correlation can also be reconstructed generally within a reasonable range of key parameters adopted, though the population of HMXBs is distinct with that in the canonical α
CE-formalism. We compare the spatial distribution of HMXBs under the two CE mechanisms, and suggest the difference in L
X versus R distribution may provide an additional clue for the study of the CE phase and to discriminate between CE models.
Brain network effects by continuous theta burst stimulation in mal de débarquement syndrome: simultaneous EEG and fMRI study
Authors: Chen Yafen , Cha Yoon-Hee , Gleghorn Diamond , Doudican Benjamin C , Shou Guofa , Ding Lei , Yuan Han
Published: October 2021

Objective. Heterogeneous clinical responses to treatment with non-invasive brain stimulation are commonly observed, making it necessary to determine personally optimized stimulation parameters. We investigated neuroimaging markers of effective brain targets of treatment with continuous theta burst stimulation (cTBS) in mal de débarquement syndrome (MdDS), a balance disorder of persistent oscillating vertigo previously shown to exhibit abnormal intrinsic functional connectivity. Approach. Twenty-four right-handed, cTBS-naive individuals with MdDS received single administrations of cTBS over one of three stimulation targets in randomized order. The optimal target was determined based on the assessment of acute changes after the administration of cTBS over each target. Repetitive cTBS sessions were delivered on three consecutive days with the optimal target chosen by the participant. Electroencephalography (EEG) was recorded at single-administration test sessions of cTBS. Simultaneous EEG and functional MRI data were acquired at baseline and after completion of 10–12 sessions. Network connectivity changes after single and repetitive stimulations of cTBS were analyzed. Main results. Using electrophysiological source imaging and a data-driven method, we identified network-level connectivity changes in EEG that correlated with symptom responses after completion of multiple sessions of cTBS. We further determined that connectivity changes demonstrated by EEG during test sessions of single administrations of cTBS were signatures that could predict optimal targets. Significance. Our findings demonstrate the effect of cTBS on resting state brain networks and suggest an imaging-based, closed-loop stimulation paradigm that can identify optimal targets during short-term test sessions of stimulation.

ClinicalTrials.gov Identifier: NCT02470377.
The potential of Climate Field Schools to boost small-scale farmers’ adaptation capacity
Authors: Hollburg Maximilian , Stöber Silke
Published: October 2021

Increasing temperature and changing rainfall patterns cause a decrease in agricultural production. Adapting to climate change is one of the major challenges of farmers in Indonesia. Since the climate will continue to change in the future, it is important to understand the determinants of adaptation in order to know how to support this adaptation process. This study identifies the link between perception and adaptation, in addition to the driving forces for adopting one or more of a set of 21 farm-level adaptation strategies. A survey was conducted among 74 participants of a Climate Field School in Tana Toraja, South Sulawesi, Indonesia. The 2-step Heckman estimation model that was used analyses the link between perception of and adaptation to climate change. The results indicate that better educated farmers and farmers with no off-farm income are more likely to adapt. The logistic regression model demonstrates that the possession of livestock increases the likelihood of applying a wider range of adaptation strategies. The Climate Field Schools offer a promising approach for enabling farmers to select appropriate adaptation strategies. However, other factors need to be considered to make best use of the potential of sustainable adaptation.
Magnetism-controlled assembly of composite stem cell spheroids for the biofabrication of contraction-modulatory 3D tissue
Authors: Byun Hayeon , Lee Sangmin , Jang Gyu Nam , Lee Hyoryong , Park Sukho , Shin Heungsoo
Published: October 2021

Biofabrication of organ-like engineered 3D tissue through the assembly of magnetized 3D multi-cellular spheroids has been recently investigated in tissue engineering. However, the cytotoxicity of magnetic nanoparticles (MNPs) and contraction-induced structural deformation of the constructs have been major limitations. In this study, we developed a method to fabricate composite stem cell spheroids using MNP-coated fibers, alleviating MNP-mediated toxicity and controlling structural assembly under external magnetic stimuli. The MNP-coated synthetic fibers (MSFs) were prepared by coating various amounts of MNPs on the fibers via electrostatic interactions. The MSFs showed magnetic hysteresis and no cytotoxicity on 2D-cultured adipose-derived stem cells (ADSCs). The composite spheroids containing MSFs and ADSCs were rapidly formed in which the amount of impregnated MSFs modulated the spheroid size. The fusion ofin vitrocomposite spheroids was then monitored at the contacting interface; the fused spheroids with over 10μg of MSF showed minimal contraction after 7 d, retaining around 90% of total area ratio regardless of the number of cells, indicating that the presence of fibers within the composite spheroid supported its structural maintenance. The fusion of MSF spheroids was modulated by external magnetic stimulation, and the effect of magnetic force on the movement and fusion of the spheroids was investigated using COMSOL simulation. Finally, ring and lamellar structures were successfully assembled using remote-controlled MSF spheroids, showing limited deformation and high viability up to 50 d duringin vitroculture. In addition, the MSFs demonstrated no adverse effects on ADSC osteochondral differentiation. Altogether, we envision that our magnetic assembly system would be a promising method for the tissue engineering of structurally controlled organ-like constructs.