bluuebunny/crossref_metadata_2025 huggingface dataset:
Increasing Synchronous Fire Danger in Forests of the Western United States
Authors: Abatzoglou John T. , Juang Caroline S. , Williams A. Park , Kolden Crystal A. , Westerling Anthony LeRoy
Published: December 2020

Widespread fire activity taxes suppression resources and can compound wildfire hazards. We examine the geographic synchronicity of fire danger across western United States forests as a proxy for the strain on fire suppression resource availability. Interannual variability in the number of days with synchronous fire danger, defined as fire weather indices exceeding the local 90th percentile across ≥40% of forested land, was strongly correlated (r = 0.85) with the number of days with high strain on national fire management resources. A 25‐day increase in the annual number of days with synchronous fire danger was observed during 1979–2020. Climate projections show a doubling of such days by 2051–2080. Such changes will escalate the likelihood of years with extended periods of synchronous fire danger that have historically strained suppression efforts and contributed to additional burned area, therein requiring additional management strategies for coping with anticipated surges in fire suppression demands.
Fluvial Channel Branching Enforces Threshold Relief
Authors: Cunningham Maxwell T. , Kaplan Michael R.
Published: December 2020

Relief within mountain belts appears to be limited to a threshold of 1,000–1,500 m. However, it remains unclear definitively where in the landscape this threshold is found. Here we use a new method of analysis, termed Progressive Hypsometry, to show that “threshold relief” is the typical relief of first‐order fluvial catchments. The method tracks changes in the elevation frequency distribution (hypsometry) across nested catchments of all sizes. We find that self‐similar nesting of fluvial catchments leads to quasi‐scale invariance in hypsometry, such that the relief between any catchment's modal and outlet elevation (RMo, mode relief) falls into three groups: the two lower associated with steep upland subcatchments (RMo = 250–1,000 m) and the other with fluvial catchments, which span orders of magnitude in area but maintain an RMo of 1,000–1,500 m. We conclude that threshold relief is the maximum relief a first‐order fluvial catchment can develop without branching.
Pluto's Antipodal Terrains Imply a Thick Subsurface Ocean and Hydrated Core
Authors: Denton C. Adeene , Johnson Brandon C. , Wakita Shigeru , Freed Andrew M. , Melosh H. Jay , Stern S. Alan
Published: December 2020

Recent analysis of New Horizons data revealed an ∼1,000‐km‐diameter region of large‐scale lineations antipodal to Sputnik Planitia, the 1,200 × 2,000 km elliptical impact basin on Pluto's anti‐Charon hemisphere. At the available resolution, these lineations are similar to antipodal terrains associated with large impact basins elsewhere in the Solar System. Here, we simulate the Sputnik Planitia‐forming impact and track stress waves through a Pluto‐like target body to the antipode. We find that the Sputnik Planitia‐forming impact is capable of producing significant antipodal terrains and the observed lineations may be extensional graben. The extent and mode of deformation at the antipode, however, is sensitive to ocean thickness and core composition. Simulations that best reproduce the observed terrains imply that Pluto may have hosted a >150‐km‐thick ocean and a hydrated core at the time of impact.
3D landscape of Hepatitis B virus interactions with human chromatins
Authors: Yang Bo , Li Boyuan , Jia Liyang , Jiang Yongpeng , Wang Xin , Jiang Shaodong , Du Shunda , Ji Xiong , Yang Pengyuan
Published: December 2020

Hepatitis B viral (HBV) DNAs, including covalently closed circular DNA (cccDNA) and integrated HBV DNA forms, are considered to be primary contributors to the development and progression of HBV-associated liver diseases. However, it remains largely unclear how HBV DNAs communicate with human chromatin. Here we employed a highly sensitive technology, 3C-high-throughput genome-wide translocation sequencing (3C-HTGTS), to globally identify HBV DNA–host DNA contacts in cellular models of HBV infection. HBV DNA does not randomly position in host genome but instead preferentially establishes contacts with the host DNA at active chromatin regions. HBV DNA–host DNA contacts are significantly enriched at H3K4me1-marked regions modified by KMT2C/D; this histone modification is also observed in the HBV cccDNA mini-chromosome and strongly influences HBV transcription. On the other hand, chromatin loop formed by integrated HBV DNA with host genomic DNA was found in transcriptionally active regions. Furthermore, HBV infection influences host gene expression accompanied with HBV DNA–host DNA contacts. Our study provides a 3D landscape of spatial organization of cccDNA and integrated HBV DNA within the human genome, which lays the foundation for a better understanding of the mechanisms how HBV involves in liver disease development and progression.
Single-cell RNA sequencing reveals regulation of fetal ovary development in the monkey (Macaca fascicularis)
Authors: Zhao Zheng-Hui , Li Chun-Yang , Meng Tie-Gang , Wang Yan , Liu Wen-Bo , Li Ang , Cai Yi-Jun , Hou Yi , Schatten Heide , Wang Zhen-Bo , Sun Qing-Yuan , Sun Qiang
Published: December 2020

Germ cells are vital for reproduction and heredity. However, the mechanisms underlying female germ cell development in primates, especially in late embryonic stages, remain elusive. Here, we performed single-cell RNA sequencing of 12,471 cells from whole fetal ovaries, and explored the communications between germ cells and niche cells. We depicted the two waves of oogenesis at single-cell resolution and demonstrated that progenitor theca cells exhibit similar characteristics to Leydig cells in fetal monkey ovaries. Notably, we found that ZGLP1 displays differentially expressed patterns between mouse and monkey, which is not overlapped with NANOG in monkey germ cells, suggesting its role in meiosis entry but not in activating oogenic program in primates. Furthermore, the majority of germ cell clusters that sharply express PRDM9 and SPO11 might undergo apoptosis after cyst breakdown, leading to germ cell attrition. Overall, our work provides new insights into the molecular and cellular basis of primate fetal ovary development at single-cell resolution.
Optimized microwave-assisted functionalization and quantification of superficial amino groups on porous silicon nanostructured microparticles
Authors: Cisneros-Covarrubias Cándida Anahy , Palestino Gabriela , Gómez-Durán César F. A. , Rosales-Mendoza Sergio , Betancourt-Mendiola María de Lourdes
Published: December 2020

MW-irradiation decreases APTES polymerization and enhances the number of NH2 attached to porous silicon surfaces.
Efficient removal of Pb2+ and Cd2+ using a Cu(i)–Br coordination polymer constructed with an amino-rich ligand
Authors: Hou Qin , Yang Qingfeng , Miao Chengxia , Duan Junling , Zhang Yuanhong , Ai Shiyun
Published: December 2020

Coordination polymers with amino-rich ligands can rapidly and efficiently remove Pb2+ and Cd2+. The adsorption capacity were found to be 598.8 mg g−1 and 2175 mg g−1, respectively.
Low-temperature Raman spectroscopy of sodium-pump rhodopsin from Indibacter alkaliphilus: insight of Na+ binding for active Na+ transport
Authors: Nakamizo Yushi , Fujisawa Tomotsumi , Kikukawa Takashi , Okamura Akiko , Baba Hiroaki , Unno Masashi
Published: December 2020

We carried out the low-temperature Raman measurement of a sodium pump rhodopsin from Indibacter alkaliphilus with/without Na+ to examine the structural change for the light-driven Na+ pump.
The photocatalytic activity of the SnO2/TiO2/PVDF composite membrane in rhodamine B degradation
Authors: Hong Wei , Li Chengcai , Tang Tao , Xu Huan , Yu Yuan , Liu Guojin , Wang Feng , Lei Caihong , Zhu Hailin
Published: December 2020

The immobilization of photocatalysts is considered an effective approach to solve the problem of the difficult recycling of powdered nanocatalysts after photocatalytic degradation.
Revealing the contribution of singlet oxygen in the photoelectrochemical oxidation of benzyl alcohol
Authors: Arcas Ramón , Peris Eduardo , Mas-Marzá Elena , Fabregat-Santiago Francisco
Published: December 2020

Analysis of photoelectrochemical oxidation of benzyl alcohol reveals a non-electrochemical UV-light process, with a huge impact on the reaction performance.
Block copolymers based on poly(butylene adipate) and poly(l-lactic acid) for biomedical applications: synthesis, structure and thermodynamical studies
Authors: Karava Vasiliki , Siamidi Aggeliki , Vlachou Marilena , Christodoulou Evi , Zamboulis Alexandra , Bikiaris Dimitrios N. , Kyritsis Apostolos , Klonos Panagiotis A.
Published: December 2020

The synthesis, structure, crystallization, semicrystalline morphology and molecular mobility of renewable/biodegradable block copolymers based on poly(butylene adipate) and poly(l-lactic acid).
Synthesis of core–shell Co@S-doped carbon@ mesoporous N-doped carbon nanosheets with a hierarchically porous structure for strong electromagnetic wave absorption
Authors: Wen Bo , Yang Haibo , Lin Ying , Ma Liang , Qiu Yun , Hu Fanfan , Zheng Yanan
Published: December 2020

Electromagnetic wave absorbents with hierarchically porous and core–shell structures have significantly positive influence on the electromagnetic wave absorption because of the enhanced interfacial polarization.
Bulk boron doping and surface carbon coating enabling fast-charging and stable Si anodes: from thin film to thick Si electrodes
Authors: Han Xiang , Zhang Ziqi , Chen Huixin , Luo Linshan , Zhang Qiaobao , Chen Jizhang , Chen Songyan , Yang Yong
Published: December 2020

Surface carbon coating and bulk boron doping enabling high-rate and long durable Si anode.
Ester-functionalized, wide-bandgap derivatives of PM7 for simultaneous enhancement of photovoltaic performance and mechanical robustness of all-polymer solar cells
Authors: You Hoseon , Jones Austin L. , Ma Boo Soo , Kim Geon-U , Lee Seungjin , Lee Jin-Woo , Kang Hyunbum , Kim Taek-Soo , Reynolds John R. , Kim Bumjoon J.
Published: December 2020

Photovoltaic performance and mechanical robustness of all-polymer solar cells are simultaneously enhanced by developing ester-functionalized, wide-bandgap PM7 derivatives.
PSMA-targeted melanin-like nanoparticles as a multifunctional nanoplatform for prostate cancer theranostics
Authors: Dai Liqun , Shen Guohua , Wang Yuanyuan , Yang Peng , Wang Hong , Liu Zhenhua
Published: December 2020

A PSMA-targeted melanin-like nanoprobe allowing for ultrasound-guided combined photodynamic/photothermal therapy (PDT/PTT) may hold great potential for precise and early theranostics of prostate cancer.
Two-step assembly kinetics of gold nanoparticles
Authors: Lyu Jieli , Alloyeau Damien , Hamon Cyrille , Constantin Doru
Published: December 2020

The assembly of surfactant-stabilized gold nanoparticles in the presence of sulfate ions takes place in two steps: fast aggregation followed by slow reordering.
Zinc ion functional doping for all-inorganic planar CsPbIBr2 perovskite solar cells with efficiency over 10.5%
Authors: Long Yongjin , Wang Chenyang , Liu Xiaohui , Wang Jiahao , Fu Shiqiang , Zhang Jing , Hu Ziyang , Zhu Yuejin
Published: December 2020

Zinc ion functional doping strategy is successfully introduced to promote the device efficiency and stability of the all-inorganic planar CsPbIBr2 perovskite solar cells.
High-performance perovskite light-emitting diodes based on double hole transport layers
Authors: Wang Weigao , Wu Zhenghui , Ye Taikang , Ding Shihao , Wang Kai , Peng Zhengchun , Sun Xiao Wei
Published: December 2020

Preparing perovskite light emitting diodes (PeLEDs) by a solution process leads to inevitable imbalanced carrier injection and solvent erosion, which prevent us from obtaining high-performance PeLEDs.
Stochastic production simulation for generating capacity reliability evaluation in power systems with high renewable penetration
Authors: Li Wanning , Wang Qin
Published: December 2020

There are increasing challenges in the power industry to plan a system that provides adequate generation capacity to sustain the load when the renewable energy penetration level is extremely high or 100%. This study proposes a stochastic production cost simulation method to evaluate the generating capacity reliability in power systems with high renewable penetration. In comparison with conventional approaches, such as planning reserve margin and probabilistic assessment, the proposed method can consider hourly chronological characteristics of the system operation, which is significant in the planning process for integrating new resources, such as storage, demand response, and renewables. The method was tested on the modified ISO New England system based on two scenarios: 45% renewable penetration and 100% clean energy. In addition, several sensitivity analyses were conducted following each scenario. Simulation results indicated that the proposed method can be used to quantify the reliability value of the system under various renewable penetration levels. When the system is not reliable, this method can be used to determine additional capacity required to ensure system reliability.
Open‐circuit fault diagnosis method for three‐level neutral point clamped inverter based on instantaneous frequency of phase current
Authors: Xu Shuiqing , Wang Juxing , Ma Mingyao
Published: December 2020

Because the three‐level neutral point clamped (NPC) inverter has the advantages of a large output capacity and high output voltage, it is widely used in wind energy and solar energy power generation. Unfortunately, the three‐level NPC inverter often suffers from open‐circuit faults, which leads to system security problems and great economic losses. To guarantee the secure operation of the three‐level NPC inverter, an open‐circuit fault diagnosis method for a three‐level NPC inverter based on the instantaneous frequency (IF) of the phase current is proposed here. First, different open‐circuit fault signals of the NPC inverter are analysed. Then, the IF of the phase current is used to obtain the fault diagnosis variables. Simultaneously, the Hilbert transform (HT) is used to estimate the IF of the phase current, which carries the information of open‐circuit faults. Meanwhile, the average value of the normalised current is provided to locate faulty switches. Finally, by combining the diagnostic variables with the identification threshold, the detection and localisation of open‐circuit faults in the NPC three‐level inverter are determined. Compared to other fault diagnosis methods, the proposed method is more stable and makes it easier to diagnose open‐circuit faults. The correctness and robustness of the method are verified by simulation results.
Astrophysical properties of newly discovered Magellanic Cloud star clusters
Authors: Piatti Andrés E.
Published: December 2020

New star cluster candidates projected toward the Large and Small Magellanic Clouds (LMC, SMC) have been recently discovered from relatively deep imaging surveys. Here, we conduct a sound analysis of 24 star cluster candidates located in the outer regions of the LMC and SMC using point spread function photometry produced by the Survey of the Magellanic Stellar History. With only one exception, the studied objects were shown to be genuine stellar aggregates. We drew our conclusions on their physical characteristics once their observed color-magnitude diagrams (CMDs) were statistically decontaminated by the presence of field stars. The resulting cleaned CMDs, for stars with assigned membership probabilities higher than 50%, were compared with synthetic CMDs generated for thousands of combinations of ages, distances, metallicities, star cluster masses, and binary fractions. The parameters of the best-matched synthetic CMDs obtained from a likelihood approach were adopted as the star cluster astrophysical properties. The present star cluster sample spans a wide range of distances, from those star clusters located in front of the LMC through those along the onset of the Magellanic Bridge up to those behind the SMC. Their ages reveal different formation episodes that took place over the course of galaxy formation and others as a consequence of interactions among galaxies. From their estimated metallicities and ages, we speculate on the possibility that relatively metal-deficient gaseous flows have existed between these galaxies during nearly the last one Gyr (log(age yr−1) ≈ 9.0), which facilitated the formation of young star clusters in the galaxy peripheries. Despide the LMC-SMC interactions, the studied star clusters are similar or more massive than their counterparts in the Milky Way, suggesting that tidal effects are relatively more important in our Galaxy.
Analysis of an Inherited Dysfibrinogenemia Pedigree Associated with a Heterozygous Mutation in the FGA Gene
Authors: Li Shaoxi , Wang Mingshan , Li Xiaolong , Xu Qiyu , Liu Siqi , Luo Shasha , Chen Yi
Published: December 2020

Objective This article aims to analyze the phenotype and genotype of an inherited dysfibrinogenemia pedigree associated with a heterozygous mutation in the FGA gene, and to investigate the pathogenesis of this disease.

Clinical Presentation The proband of interest is a 29-year-old woman. She was in her 37 weeks of gestation. Routine coagulation tests showed low fibrinogen activity (0.91 g/L; normal range: 2.0–4.0 g/L) and normal fibrinogen antigen (FIB:Ag) level (2.09 g/L; normal range: 2.0–4.0 g/L).

Techniques The prothrombin time, activated partial thromboplastin time, thrombin time, and activity of plasma fibrinogen (FIB:C) were detected by the one-stage clotting method. The FIB:Ag, D-dimer, and fibrinogen degradation products were tested by the immunoturbidimetry method. To identify the novel missense mutation, fibrinogen gene sequencing and molecular modeling were performed. We used ClustalX-2.1-win and online bioinformatic software to analyze the conservation and possible effect of the amino acid substitution on fibrinogen.

Results Phenotypic analysis revealed that the FIB:C of the proband was significantly reduced while the FIB:Ag was normal. Sequencing analysis detected a heterozygous C.2185G > A point mutation in the FGA gene (AαGlu710Lys). Bioinformatic and modeling analyses indicated that the mutation probably caused harmful effects on fibrinogen.

Conclusion The heterozygous mutation of Glu710Lys in the FGA gene was identified that could cause the reduction of the FIB structure stability and result in the dysfibrinogenemia.
Lung Ultrasound for Predicting the Respiratory Outcome in Patients with Bronchopulmonary Dysplasia
Authors: Hoshino Yusuke , Arai Junichi , Miura Rena , Takeuchi Syusuke , Yukitake Yoshiya , Kajikawa Daigo , Kamakura Tae , Horigome Hitoshi
Published: December 2020

Objective This study aimed to investigate the utility of lung ultrasound (LUS) with whole chest scanning for predicting respiratory outcomes in patients with bronchopulmonary dysplasia (BPD).

Study Design We performed a prospective observational study. Preterm infants of less than 32 weeks' gestational age requiring oxygen therapy at 28 days of life were included. LUS was performed on day 28, at 36 weeks' postmenstrual age, and at the time of discharge. Each lung was divided into three regions by the anterior and posterior axillary lines and received an LUS score of 0 to 3 points; the total score was obtained by adding the six regional scores. The classification of BPD was determined based on the National Institute of Child and Human Development. The outcomes of this study were the development of moderate-to-severe BPD and the need for home oxygen therapy (HOT).

Results We enrolled 87 patients; 39, 33, and 15 infants had mild, moderate, and severe BPD, respectively. The LUS score correlated with BPD severity and exhibited an improvement trend with time toward the point of discharge. LUS at 28 days of life predicted moderate-to-severe BPD with an area under the curve of 0.95 (95% confidence interval: 0.91–0.99) and HOT with an area under the curve of 0.95 (95% confidence interval: 0.81–1.0).

Conclusion LUS with whole chest scanning is useful for predicting respiratory outcomes in patients with BPD, as well as for understanding BPD severity or clinical improvement trends.

Key Points
The Acylcarnitine Profile in Dried Blood Spots is Affected by Hematocrit: A Study of Newborn Screening Samples in Very-Low-Birth-Weight Infants
Authors: Haga Mitsuhiro , Isobe Mitsuhisa , Kawabata Ken , Shimizu Masaki , Mochizuki Hiroshi
Published: December 2020

Objective The acylcarnitine profile is analyzed in dried blood spots (DBS) to screen for inborn errors of metabolism. Hematocrit (Ht) is known to affect the result of quantitative analyses of DBS samples; however, the effects of Ht on the acylcarnitine profiles in DBS have not been studied in actual samples from newborns.

Study Design The acylcarnitine profiles in DBS for newborn screening tests and Ht levels of very-low-birth-weight infants were obtained from medical records. We investigated the relationship between Ht and each acylcarnitine using Pearson's correlation coefficient (r).

Results We examined 77 newborns in this study. There was a significantly positive correlation between Ht and C0, C2, C12, C16, C18, C18:1, and C18:1-OH, respectively (p < 0.0025). The correlation was the greatest on C2 (r = 0.59).

Conclusion This study clarifies that Ht and C0, C2, C12, C16, C18, C18:1, and C18:1-OH are significantly correlated in DBS, which is consistent with previous studies. Hence, the effect of Ht should be considered when interpreting the results of acylcarnitine profiles in DBS.

Key Points
Collisionless adiabatic afterglow
Authors: Khrabrov A. V. , Kaganovich I. D. , Chen J. , Guo H.
Published: December 2020

We study, by numerical and analytical means, the evolution of a collisionless plasma initiated between absorbing walls. The ensuing flow is described by rarefaction waves that travel inward from the boundaries, interact, and eventually vanish after crossing through, leading up to the asymptotic stage of the decay. Particle simulations indicate that the kinetic evolution strongly resembles one found in isentropic gas dynamics. Namely, a very gradual density profile forms in the expanding central region where the rarefaction waves interact, with an accompanying linear velocity profile. Asymptotically, the density falls off as 1/t. The density and the flux at the boundary show little variation over the period when rarefaction waves still exist. Plasma potential, on the other hand, drops quite rapidly (on the underlying ion-acoustic timescale) to less than initial electron temperature Te when over 70% of the particles still remain in the system. This is due to electron kinetics being governed by conservation of adiabatic invariant in a slowly varying potential well. Analytical model of the velocity distribution is presented to explain the simulations. The results have implications for afterglow plasmas used in material processing and also for ion-extraction devices. One property of potential interest is good uniformity of the decaying plasma that occurs after approximately one ion-acoustic time.
Toward heteroepitaxially grown semipolar GaN laser diodes under electrically injected continuous-wave mode: From materials to lasers
Authors: Li Hongjian , Zhang Haojun , Song Jie , Li Panpan , Nakamura Shuji , DenBaars Steven P.
Published: December 2020

III-nitrides based light-emitting diodes and laser diodes (LDs) have shown great success as solid-state lighting sources, but the development of common c-plane (0001) polar GaN emitters is facing limitations due to quantum-confinement Stark effect, efficiency drop, low efficiency at green range, and peak wavelength blue-shift. Efficient semipolar or nonpolar GaN light emitting diodes and LDs have been successfully demonstrated by growing on semipolar or nonpolar free-standing GaN substrates. The small size and high cost of high crystal quality semipolar or nonpolar free-standing GaN substrates, which are sliced from hydride vapor phase epitaxy grown c-plane bulk GaN substrate, have severely limited their commercial development and application. Achieving scalable heteroepitaxial semipolar GaN materials with a very low density of basal-stacking faults (BSFs) on a foreign substrate remains very challenging. The recent breakthrough in the demonstration of continuous-wave (CW) semipolar (202¯1) LDs at room-temperature on semipolar GaN/sapphire template marks a milestone in exploring high crystal quality heteroepitaxial semipolar GaN materials and low-cost semipolar emitters. Here, we review the key progress through the past years about the development of heteroepitaxial semipolar GaN materials including epitaxial lateral overgrowth, orientation controlling epitaxy, BSFs burying by neighboring Ga-polar (0001) GaN with air voids, facet-engineering orientation control epitaxy, resulting in a low density or free of basal stacking faults. Furthermore, we discuss the heteroepitaxially grown pulsed semipolar (112¯2) blue LDs and CW semipolar (202¯1) LDs.
Hybrid methods for combined experimental and computational determination of protein structure
Authors: Seffernick Justin T. , Lindert Steffen
Published: December 2020

Knowledge of protein structure is paramount to the understanding of biological function, developing new therapeutics, and making detailed mechanistic hypotheses. Therefore, methods to accurately elucidate three-dimensional structures of proteins are in high demand. While there are a few experimental techniques that can routinely provide high-resolution structures, such as x-ray crystallography, nuclear magnetic resonance (NMR), and cryo-EM, which have been developed to determine the structures of proteins, these techniques each have shortcomings and thus cannot be used in all cases. However, additionally, a large number of experimental techniques that provide some structural information, but not enough to assign atomic positions with high certainty have been developed. These methods offer sparse experimental data, which can also be noisy and inaccurate in some instances. In cases where it is not possible to determine the structure of a protein experimentally, computational structure prediction methods can be used as an alternative. Although computational methods can be performed without any experimental data in a large number of studies, inclusion of sparse experimental data into these prediction methods has yielded significant improvement. In this Perspective, we cover many of the successes of integrative modeling, computational modeling with experimental data, specifically for protein folding, protein–protein docking, and molecular dynamics simulations. We describe methods that incorporate sparse data from cryo-EM, NMR, mass spectrometry, electron paramagnetic resonance, small-angle x-ray scattering, Förster resonance energy transfer, and genetic sequence covariation. Finally, we highlight some of the major challenges in the field as well as possible future directions.
Local C–V mapping for ferroelectrics using scanning nonlinear dielectric microscopy
Authors: Hiranaga Yoshiomi , Mimura Takanori , Shimizu Takao , Funakubo Hiroshi , Cho Yasuo
Published: December 2020

Detailed analysis of local polarization switching will promote the further development of a wide range of applications using ferroelectrics. Here, we propose a local C–V mapping technique using scanning nonlinear dielectric microscopy (SNDM) that enables visualization of dynamic ferroelectric switching behavior in real space. Using this method, C–V butterfly curves characteristic of ferroelectrics can be measured on a scanning probe microscopy platform with nanoscale resolution by virtue of the high capacitance-detection sensitivity of SNDM. This provides real-space mapping of the net switchable polarization, the switching voltage, and the local imprint with a short measurement time (e.g., 10 min or less for 256×256 pixels). Furthermore, the proposed method will be useful for study of the electric-field response of domain walls. In this paper, we present some examples of experiments with LiTaO3 single crystals and HfO2-based ferroelectric thin films and give an overview of what kind of evaluation is possible with the local C–V mapping technique.
A comparative study of quasi-stable sheet cavities at different stages based on fast synchrotron x-ray imaging
Authors: Zhang Guangjian , Khlifa Ilyass , Coutier-Delgosha Olivier
Published: December 2020

The cavitating flows in a small convergent–divergent channel are studied experimentally using a fast synchrotron x-ray imaging method that enables simultaneous acquisition of the velocity and void fraction fields as well as the two-phase morphology inside the opaque cavitation areas. According to the x-ray measurement results, the quasi-stable sheet cavitation is classified into three representative stages based on the status of the re-entrant flow: (i) at the early stage, the incipient cavity is short and no reverse flow is observed, (ii) at the intermediate stage, an intermittent re-entrant flow is identified underneath the sheet cavity, and (iii) at the developed stage, the re-entrant flow becomes continuous and it can penetrate the entire sheet cavity. The comparison of the three typical sheet cavities illustrates that the occurrence of the re-entrant flow does not result in the transition of sheet-to-cloud cavitation, but it influences the distribution of the mean void fraction and the spectrum of the void fraction variation. The development of cavitation also influences the turbulent velocity fluctuations. On one hand, cavitation alters mean velocity field, which affects velocity fluctuations due to the positive correlation between the velocity gradient and turbulence intensity. One the other hand, the presence of vapor/liquid mixture is observed to greatly suppress velocity fluctuations. The collapse of small vapor structures does not cause an evident augmentation of streamwise velocity fluctuations but increases the shear stress significantly.
Insights on drying and precipitation dynamics of respiratory droplets from the perspective of COVID-19
Authors: Basu Saptarshi , Kabi Prasenjit , Chaudhuri Swetaprovo , Saha Abhishek
Published: December 2020

We isolate a nano-colloidal droplet of surrogate mucosalivary fluid to gain fundamental insights into airborne nuclei’s infectivity and viral load distribution during the COVID-19 pandemic. The salt-water solution containing particles at reported viral loads is acoustically trapped in a contactless environment to emulate the drying, flow, and precipitation dynamics of real airborne droplets. Similar experiments validate observations with the surrogate fluid with samples of human saliva samples from a healthy subject. A unique feature emerges regarding the final crystallite dimension; it is always 20%–30% of the initial droplet diameter for different sizes and ambient conditions. Airborne-precipitates nearly enclose the viral load within its bulk while the substrate precipitates exhibit a high percentage (∼80–90%) of exposed virions (depending on the surface). This work demonstrates the leveraging of an inert nano-colloidal system to gain insights into an equivalent biological system.
Acidity across the interface from the ocean surface to sea spray aerosol
Authors: Angle Kyle J. , Crocker Daniel R. , Simpson Rebecca M. C. , Mayer Kathryn J. , Garofalo Lauren A. , Moore Alexia N. , Mora Garcia Stephanie L. , Or Victor W. , Srinivasan Sudarshan , Farhan Mahum , Sauer Jon S. , Lee Christopher , Pothier Matson A. , Farmer Delphine K. , Martz Todd R. , Bertram Timothy H. , Cappa Christopher D. , Prather Kimberly A. , Grassian Vicki H.
Published: December 2020

Significance

Sea spray aerosol, produced through breaking waves, is one of the largest sources of environmental particles. Once in the atmosphere, sea spray aerosol influences cloud formation, serves as microenvironments for multiphase atmospheric chemical reactions, and impacts human health. All of these impacts are affected by aerosol acidity. Here we show that freshly emitted sea spray aerosol particles become highly acidic within minutes as they are transferred across the ocean−air interface. These results have important implications for atmospheric chemistry and climate, including aerosol/gas partitioning, heterogeneous reactions, and chemical speciation at the surface and within sea spray aerosol.
“Non-coordinating UND” in Middle and Early New High German
Authors: Oppermann Sophia Jana
Published: December 2020

Even though it has been noted quite early that the conjunction UND may also serve as a relative/equative particle
or even a subjunction in Middle High German and Early New High German, corpus-based empirical studies are lacking so far. Based on new empirical data, I show that
non-coordinating UND originated in the Upper German dialect area during the 12th century, subsequently spreading to the Central German dialect area and
reaching the peak of its use in the 14th century. In contrast to recent literature, I argue that the non-coordinating use of the
conjunction originated from semantically and syntactically ambiguous constructions of the form UND-XP-VFIN. I also propose that
the earliest instances of the phenomenon are (adverbial) relative constructions and that the temporal and the equative function
developed via reanalysis of adverbial relative clauses with a temporal/modal head element.
Factors influencing the nucleation and crystal growth of solution-processed organic lead halide perovskites: a review
Authors: Ke Lili , Luo Shiqiang , Ren Xiaoxue , Yuan Yongbo
Published: December 2020

Lead halide perovskite solar cells (PSCs) with solution processability, low defect concentration, low cost and high output manufacturing have emerged as promising third-generation photovoltaic technologies. After an unprecedented speed of development, the power conversion efficiencies of small-area PSCs have exceeded 25%, and meanwhile large-scale perovskite modules are also on a rapid rise. At this stage, considering the significant progress in the fabrication of perovskite films with controllable morphology and crystallinity, it is necessary to conduct reviews on the updated understandings of the nucleation and crystal growth behaviors of perovskites. This review aims to clarify the related mechanisms of the complex perovskite formation process, and is devoted to giving a timely summary of the recent advances. Strategies for controlling perovskite nucleation and crystal growth are also discussed.
Magnetotransport in hybrid InSe/monolayer graphene on SiC
Authors: Wang Chih-Yuan , Lin Yun-Wu , Chuang Chiashain , Yang Cheng-Hsueh , Patel Dinesh K , Chen Sheng-Zong , Yeh Ching-Chen , Chen Wei-Chen , Lin Chia-Chun , Chen Yi-Hsun , Wang Wei-Hua , Sankar Raman , Chou Fang-Cheng , Kruskopf Mattias , Elmquist Randolph E , Liang Chi-Te
Published: December 2020

The magnetotransport properties of a hybrid InSe/monolayer graphene in a SiC system are systematically studied. Compared to those of its bare graphene counterpart, in InSe/graphene, we can effectively modify the carrier density, mobility, effective mass, and electron–electron (e–e) interactions enhanced by weak disorder. We show that in bare graphene and hybrid InSe/graphene systems, the logarithmic temperature (lnT) dependence of the Hall slope R
H = δR

xy
/δB = δρ

xy
/δB can be used to probe e–e interaction effects at various temperatures even when the measured resistivity does not show a lnT dependence due to strong electron–phonon scattering. Nevertheless, one needs to be certain that the change of R
H is not caused by an increase of the carrier density by checking the magnetic field position of the longitudinal resistivity minimum at different temperatures. Given the current challenges in gating graphene on SiC with a suitable dielectric layer, our results suggest that capping a van der Waals material on graphene is an effective way to modify the electronic properties of monolayer graphene on SiC.
Novel electro self-assembled DNA nanospheres as a drug delivery system for atenolol
Authors: Elkayal Rehab , Motawea Amira , Reicha Fikry M , Elmezayyen Ayman S
Published: December 2020

We describe new method for preparing DNA nanospheres for a self-assembled atenolol@DNA (core/shell) drug delivery system. In this paper, we propose the electrochemical transformation of an alkaline polyelectrolyte solution of DNA into DNA nanospheres. We successfully electrosynthesized DNA nanospheres that were stable for at least 2 months at 4 °C. UV–visible spectra of the prepared nanospheres revealed a peak ranging from 372 to 392 nm depending on the DNA concentration and from 361 to 398.3 nm depending on the electrospherization time. This result, confirmed with size distribution curves worked out from transmission electron microscopy (TEM) images, showed that increasing electrospherization time (6, 12 and 24 h) induces an increase in the average size of DNA nanospheres (48, 65.5 and 117 nm, respectively). In addition, the average size of DNA nanospheres becomes larger (37.8, 48 and 76.5 nm) with increasing DNA concentration (0.05, 0.1 and 0.2 wt%, respectively). Also, the affinity of DNA chains for the surrounding solvent molecules changed from favorable to bad with concomitant extreme reduction in the zeta potential from −31 mV to −17 mV. Principally, the attractive and hydrophobic interactions tend to compact the DNA chain into a globule, as confirmed by Fourier transform infrared spectroscopy (FTIR) and TEM. To advance possible applications, we successfully electro self-assembled an atenolol@DNA drug delivery system. Our findings showed that electrospherization as a cost–benefit technique could be effectively employed for sustained drug release. This delivery system achieved a high entrapment efficiency of 68.03 ± 2.7% and a moderate drug-loading efficiency of 3.73%. The FTIR spectra verified the absence of any chemical interaction between the drug and the DNA during the electrospherization process. X-ray diffraction analysis indicated noteworthy lessening in atenolol crystallinity. The present findings could aid the effectiveness of electrospherized DNA for use in various other pharmaceutical and biomedical applications.
A commercial treatment planning system with a hybrid dose calculation algorithm for synchrotron radiotherapy trials
Authors: Day L R J , Donzelli M , Pellicioli P , Smyth L M L , Barnes M , Bartzsch S , Crosbie J C
Published: December 2020

Synchrotron Radiotherapy (SyncRT) is a preclinical radiation treatment which delivers synchrotron x-rays to cancer targets. SyncRT allows for novel treatments such as Microbeam Radiotherapy, which has been shown to have exceptional healthy tissue sparing capabilities while maintaining good tumour control. Veterinary trials in SyncRT are anticipated to take place in the near future at the Australian Synchrotron's Imaging and Medical Beamline (IMBL). However, before veterinary trials can commence, a computerised treatment planning system (TPS) is required, which can quickly and accurately calculate the synchrotron x-ray dose through patient CT images. Furthermore, SyncRT TPS's must be familiar and intuitive to radiotherapy planners in order to alleviate necessary training and reduce user error. We have paired an accurate and fast Monte Carlo (MC) based SyncRT dose calculation algorithm with EclipseTM, the most widely implemented commercial TPS in the clinic. Using EclipseTM, we have performed preliminary SyncRT trials on dog cadavers at the IMBL, and verified calculated doses against dosimetric measurement to within 5% for heterogeneous tissue-equivalent phantoms. We have also performed a validation of the TPS against a full MC simulation for constructed heterogeneous phantoms in EclipseTM, and showed good agreement for a range of water-like tissues to within 5%–8%. Our custom EclipseTM TPS for SyncRT is ready to perform live veterinary trials at the IMBL.
Nonlinear Thomson scattering from a tightly focused circularly polarized laser with varied incident-pulse durations
Authors: Wang Yiqiu , Wang Conglin , Zhou Qinyan , Li Lingxiao , Tian Youwei
Published: December 2020

In this paper, nonlinear Thomson scattering in an intense (

a
0

=
6

) tightly focused (

b
0

=
3

μ

m

) Gaussian laser pulse is theoretically and numerically investigated to demonstrate varying spatial characteristics in the few-cycle and multi-cycle domains. We find that within ultrashort incident laser pulses, electrons have the potential to radiate a single attosecond pulse with a large signal-to-noise ratio, which turns into a train of attosecond pulses with a multi-cycle laser. Furthermore, a novel asymmetry phenomenon is discovered for the first time in the few-cycle domain whereby spatial radiation lasts for only one circle with apparent peaks and valleys, in contrast to the helical radiation pattern apparent in the multi-cycle domain, which gradually turns into a common fourfold-symmetry pattern. This means that the difference between tightly and non-tightly focused laser pulses can be bridged utilizing an appropriate incident pulse duration under specific conditions. The above difference is demonstrated again in the polar plane, where electrons change from a light-spot to a light-band radiation feature when the incident pulse duration increases.
Computer simulation of traffic flows
Authors: Kasatkina E V , Vavilova D D
Published: December 2020

The paper is presented to the simulation of traffic flows in conditions of traffic light regulation. A simulation multi-agent model of traffic flows was developed, which includes three agents: a car, a traffic light, a generator. A computational algorithm for the movement of vehicles for imitating the movement of vehicles along the driving lanes and its behavior at the intersection was developed. The simulation multi-agent model and the computational algorithm are implemented in the form of an intelligent analytical system that includes a database designed in the MS SQL DBMS environment, as well as a visualization module. During the simulation of traffic flows in the system, the required output parameters of the model are fixed. By simulation tools one of the problematic road sections of the city of Izhevsk was built, including a network of intersections of 10 years of October Street, Udmurtskaya Street, Pushkinskaya Street. The developed simulation model allows calculating the indicators of the average queue length at different times of the day, taking into account the intensity of input traffic flows. Thus, graphs of the dynamics of changes in the average queue length can be obtained and, on their basis, the time periods of congestion occurrence are determined. For example, during the simulation of the operation of a section of the transport network of the city of Izhevsk, it was established that there are two time periods for the occurrence of traffic congestion: from 7:00-9:00 AM and 5:00-7:00 PM, in which the indicator of the maximum queue length reaches 40 cars.
Method for the Blind Estimation of Power Coefficients in PD-NOMA Systems
Authors: Kryukov Ya V , Pokamestov D A , Rogozhnikov E V , Movchan A K , Kvashnina A S
Published: December 2020

A method of power domain non-orthogonal multiple access with user channel multiplexing is a promising approach for organizing multichannel communication in modern digital wireless systems. Generation of a non-orthogonal group signal involves the superposition of user signals with different weight power coefficients in a single frequency-time resource segment. Decoding such a signal at the receiver requires the information about the weights used in multiplexing. This information is transmitted in control channels and provides additional load on the data network, which in turn reduces its effectiveness. A blind estimation method of power coefficients is proposed to solve this issue. A simulation model has been developed to study proposed method. Simulation resulted in the dependence of the blind estimation of power coefficients error on the signal-to-noise ratio in the transmission channel and on the signal sample length. The result of the study showed that the blind estimation of power coefficients insignificantly worsens the probability of a bit error when decoding a group non-orthogonal signal. Despite this, the proposed blind estimation method can be considered in an attempt to optimize control channel traffic.
Description and implementation of the Supersonic Shear Imaging method on the Verasonics research system
Authors: Spivak A E , Demin I Yu
Published: December 2020

The method of shear wave elastography Supersonic Shear Imaging is presented. A scheme for implementing this method on the Verasonics research system and an algorithm for processing and outputting data as an elasticity map are developed. Physical modelling was carried out with a CIRS model 049 elasticity phantom on the Verasonics research system using SSI and SWEI methods, and on the Supersonic Aixplorer ultrasound system. The results were compared and shown the method presented to be applicable for the research system.
Hybrid modelling of the RED algorithm in the Julia language
Authors: Apreutesey A M Yu , Korolkova A V , Kulyabov D S
Published: December 2020

This work is devoted to studying the possibilities of hybrid modeling of communication network algorithms in the Julia programming language. A simulation of the system, which consists of an incoming stream processed according to the Transmission Control Protocol (TCP) and a router processing traffic according to the Random Early Detection (RED) algorithm, is carried out. This model contains both continuous and discrete elements, for example, a discrete probability function of random packet dropping in the case of queue congestion.
Dispatching method of incoming events for ERP system based on analysis of emails using artificial intelligent technique
Authors: Shirokov S A , Rypalov A J
Published: December 2020

The article describes a method for solving automatic dispatching problem of incoming events in ERP systems received from incoming emails via external mail programs by using artificial intelligent processing. Realization include recognition of client appeal subject, selecting key information and transferring it to enterprise business processes through creation of tasks. In this research, was developed program module for ERP system based on “1C: Enterprise” platform and integrated with an external mail application and neural network oriented to natural language recognition. As a result, it made possible to embed that mechanism into business processes engine of the information system and solve the problem in practice.
Nucleation of nano-islands of pure components during growth of a multicomponent crystal via step-flow mode
Authors: Redkov A V , Kukushkin S A
Published: December 2020

The work is devoted to an analysis of the processes taking place at the surface of the multicomponent crystal during its growth via step-flow mode. It is shown, that at certain conditions nucleation of pure components in a form of nanoislands can take place at the terraces between the steps. The mechanism of formation of such islands is discussed. The criterion for the conditions at which such nucleation takes place is derived.
On the synthesis of the carboxylated graphene via graphene oxide liquid-phase modification with alkaline solutions
Authors: Ryzhkov S A , Rabchinskii M K , Shnitov V V , Baidakova M V , Pavlov S I , Kirilenko D A , Brunkov P N
Published: December 2020

In this work we present a facile method for the synthesis of the carboxylated graphene derivate. The resulting material contains up to 10.9 at.% of carboxyl groups and with negligible content of other oxygen-containing groups. Moreover, formation of large round-shaped nanoscale holes is observed due to the applied synthesis process. The synthesized graphene derivative is of high interest for the sensing applications due to combination of its conductive nature and chemical reactivity provided by the attached carboxyl groups.