bluuebunny/crossref_metadata_2025 huggingface dataset:
Frictional Segmentation of the Chilean Megathrust From a Multivariate Analysis of Geophysical, Geological, and Geodetic Data
Authors: Molina Diego , Tassara Andrés , Abarca Rodrigo , Melnick Daniel , Madella Andrea
Published: May 2021

We present a formal seismic segmentation model of the Chile Margin derived from a multivariate analysis of gravity anomalies, basal friction and interplate locking from GPS velocities. These independent proxies of the frictional structure along the megathrust integrate over timescales of 101–107 years. We analyze their covariance using Principal Component Analysis (PCA) and extracting the Empirical Orthogonal Functions (EOFs) and Principal Components (PCs). We find that (a) the first and first + second PCA modes for the triple combination of the proxies explain (respectively) 41.4% and 69.4% of the total variance and (b) the first‐order spatial pattern of each isolated proxy is largely reproduced when it is combined with the other two proxies. This suggests that the three proxies share a first order along‐trench tendency that must be connected through a common physical process. Comparing our results with rupture areas of earthquakes and using the rate‐and‐state friction theory, we infer that trench‐perpendicular PCs reflect the limits of the velocity‐weakening (VW) seismogenic zone. Polarity changes in along‐trench EOFs (mostly for gravity) mark changes between unstable and conditionally stable frictional regimes inside the VW zone and we used them to define the boundaries of 17 unitary segments. These segments correlate with first‐order tectonic features of the Andes at >103‐km scales as well as with zones of multi‐segment ruptures at 102‐km scale. We analyze the combined influence of subducting and upper‐plate geologic features on the nature of persistent seismic barriers. Our results have implications for understanding seismotectonic processes along the Andean margin and elsewhere.
The Effect of Depth‐Dependent Stress in Controlling Free‐Surface‐Induced Supershear Rupture on Strike‐Slip Faults
Authors: Hu Feng , Oglesby David D. , Chen Xiaofei
Published: May 2021

Supershear rupture is crucial in determining ground motion characteristics and its various transition mechanisms is in key connection with rupture dynamics, geometrical complexities and stress heterogeneities. Using 3D dynamic rupture models with numerous depth‐dependent stress regimes, we show that depth‐dependent stress plays a major role in controlling the occurrence of free‐surface‐induced (FSI) supershear ruptures. The effect of stress gradient, initial normal stress at the free surface, fault width and critical depth of depth‐dependent stress regime are examined. The 2D tangent rupture velocity distributions show that generation of a sustained FSI supershear rupture prefers a larger stress gradient and initial normal stress at the free surface. The truncation of fault width could transit the rupture to a sub‐Rayleigh rupture. We propose a dimensionless stress parameter representing a measure of the overall level of depth‐dependence in the initial normal stress, and a larger moment magnitude is more likely to trigger a sustained FSI supershear rupture. By comparing the near‐field ground motions, three distinct ground motion characteristics are presented using the sustainability of Mach fronts and displacement polarization. This work helps to understand the occurrence of FSI supershear ruptures and its relationship with underground depth‐dependent stresses.
Air Pollution Zone Migrates South Driven by East Asian Winter Monsoon and Climate Change
Authors: Zhao Shuyu , Feng Tian , Tie Xuexi , Li Guohui , Cao Junji
Published: May 2021

A variety of climatological indices have been established to illustrate the impact of climate change on air pollution in China, but major facts for causing variations of air pollution attributed to climate change are still unclear. Here, using in‐situ PM2.5 (particles with the aerodynamic diameter less than 2.5 μm) measurement, atmospheric reanalysis data and a chemical transport model, we show that meridional distribution of PM2.5 loadings is strongly modulated by the intensity of East Asian winter monsoon (EAWM). The EAWM drives the heavily polluted zone in eastern China to migrate southward, i.e., under stronger EAWM, more southward migration of air pollution occurs. We expect that the migration will likely re‐distribute carbon sources‐ and sinks‐related ecosystem, posing a new challenge for the Chinese government, who needs to implement region‐different emission reduction plans in the future, to mitigate air pollution and to go carbon neutral.
Habit‐Dependent Vapor Growth Modulates Arctic Supercooled Water Occurrence
Authors: Silber Israel , McGlynn Paul S. , Harrington Jerry Y. , Verlinde Johannes
Published: May 2021

We present an analysis of long‐term data collected at Utqiaġvik, Alaska, to explore the impacts of cloud processes on the probability of finding supercooled water given cloud temperature, P(L|T), in the topmost unseeded liquid‐bearing layers. P(L|T) has local minima at temperatures around −6°C and −15°C. Simulations using habit‐evolving ice microphysics models suggest that these minima are the result of efficient vapor growth by non‐isometric habits found at these temperatures. We conclude that habit‐dependent vapor growth of ice crystals modulates the macrophysical occurrence of supercooled water in polar clouds, the effect of which should be included in model parametrizations to avoid biases and/or error compensation. Our methodology is adaptable for spherical ice treatments implemented in models (example parametrizations provided), amenable for use with satellite measurements to give global impartial observational targets for model evaluations, and may allow empirical characterization of bulk responses to seeding and possibly secondary ice effects.
Disrupted Stratospheric QBO Signatures in the Diurnal Tides Over the Low‐Latitude MLT Region
Authors: Pramitha M. , Kishore Kumar K. , Venkat Ratnam M. , Praveen M. , Rao S. Vijaya Bhaskara
Published: May 2021

Meteor radar measurements of winds in the mesosphere and lower thermosphere (MLT) over Tirupati (13.63°N, 79.4°E; 2013–2020) and Microwave Limb Sounder (MLS) observations of ozone are used for investigating the effect of the disrupted stratospheric quasi‐biennial oscillation (SQBO) during the year 2016 on the diurnal tides. The positive tidal perturbations are observed during positive perturbations of ozone and eastward phase of the SQBO and vice versa. These observations are well captured by the Specified Dynamics Whole Atmosphere Community Climate Model (SD‐WACCM) simulations. The results suggest that the ozone and wind perturbations in the stratosphere induced by the sudden phase transition in the SQBO winds are the potential candidates for the observed abrupt changes in the diurnal tide amplitudes in the MLT region. The SQBO disruption thus provided an opportunity to seek further insights into the pathways through which the lower atmosphere influence the middle and upper atmosphere.
Multiscale Nature of the Magnetotail Reconnection Onset
Authors: Sitnov M. I. , Motoba T. , Swisdak M.
Published: May 2021

Mining of substorm magnetic field data reveals the formation of two X‐lines preceded by the flux accumulation at the tailward end of a thin current sheet (TCS). Three‐dimensional particle‐in‐cell simulations guided by these pre‐onset reconnection features are performed, taking also into account weak external driving, negative charging of TCS and domination of electrons as current carriers. Simulations reveal an interesting multiscale picture. On the global scale, they show the formation of two X‐lines, with stronger magnetic field variations and inhomogeneous electric fields found closer to Earth. The X‐line appearance is preceded by the formation of two diverging electron outflow regions embedded into a single diverging ion outflow pattern and transforming into faster electron‐scale reconnection jets after the onset. Distributions of the agyrotropy parameters suggest that reconnection is provided by ion and then electron demagnetization. The bulk flow and agyrotropy distributions are consistent with MMS observations.
Hydroxylation of Apollo 17 Soil Sample 78421 by Solar Wind Protons
Authors: McLain J. L. , Loeffler M. J. , Farrell W. M. , Honniball C. I. , Keller J. W. , Hudson R.
Published: May 2021

Hydroxylation by solar wind protons has been simulated in our laboratory on Apollo 17 lunar sample 78421, a very mature regolith sample that is rich with agglutinates (68%). The goal of this study was to determine the rate of hydroxyl formation and their thermal stability by monitoring changes in the SiOH (hydroxyl) stretching band near 3 μm using diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS). A 2 keV H2+ ion beam was used to simulate proton implantation on 78421 and on a crushed fused silica sample. We find that the OH band does not change unless the samples have been annealed in vacuum prior to irradiation. Qualitatively, the OH bands for the fused silica and 78421 are very different. The OH band for fused silica is centered at 2.74 μm and is relatively sharp ranging from 2.67 to 3.1 μm at full width at half maximum (FWHM), while the OH band for 78421 is centered at 3.0 μm and ranges from 2.74 to 3.37 μm at FWHM. The increase in wavelength and broadened nature of the OH band in 78421 may be associated with the OH’s proximity to surface defects and/or lattice vacancies. The lack of the H2O bending mode at 6.1 μm indicates that any adsorbed terrestrial H2O is below our detection limit, and therefore the H2O stretching mode at 2.9 μm is not significantly contributing to the broad 3 μm OH band and implies that proton implantation by itself does not lead to water formation. To simulate the maximum dayside temperature on the lunar surface, the lunar sample was heated after proton irradiation. The proton induced OH concentration was reduced by as much as 25% after heating to 400 K (127°C).
Impact of Artificial Floods on the Quantity and Grain Size of River‐Borne Sediment: A Case Study of a Dam Regulation Scheme in the Yellow River Catchment
Authors: Wu Xiao , Wang Houjie , Bi Naishuang , Xu Jingping , Nittrouer Jeffrey A. , Yang Zuosheng , Lu Taian , Li Peihua
Published: May 2021

The quantity and grain size of river‐borne sediment are critical to geomorphological evolution and ecosystem health of river deltas. Compared to quantitative aspects of fluvial systems, however, studies describing the physical properties of river sediment are still quite limited. This work examines how an unprecedented engineering effort (the Water‐Sediment Regulation Scheme, WSRS) within the lower Yellow River system has caused important changes in the volume and grain size patterns of transported sediment. After the implementation of the WSRS, artificial floods dominated the delivery of water and sediment to the delta region—the natural (seasonal) rhythm of the hydrological cycle has been replaced by impulsive delivery. Compared to natural floods, the duration of the artificial flood due to WSRS is substantially shortened, and timing has changed to early summer (June to July), which is two to three months ahead of the usual flood season. Now, as a result of WSRS, there are high sediment loads over a shorter than usual time frame. The Yellow River's sediment load rebounded and coarsened, because artificial floods have strongly scoured the river channel. These changes turned the Yellow River delta from a recession phase to one of progradation, and caused impulsive delivery and rapidly buried of terrestrial organic carbon and pollutants. For other rivers worldwide, the lower Yellow River system provides an illustrative example of how transporting coarse‐grained sediment, otherwise deposited on river bed, may be used to mitigate coastal land loss on intra‐decadal time scales, however with the potential for adverse ecological impacts.
Binding moral values gain importance in the presence of close others
Authors: Yudkin Daniel A. , Gantman Ana P. , Hofmann Wilhelm , Quoidbach Jordi
Published: May 2021

A key function of morality is to regulate social behavior. Research suggests moral values may be divided into two types: binding values, which govern behavior in groups, and individualizing values, which promote personal rights and freedoms. Because people tend to mentally activate concepts in situations in which they may prove useful, the importance they afford moral values may vary according to whom they are with in the moment. In particular, because binding values help regulate communal behavior, people may afford these values more importance when in the presence of close (versus distant) others. Five studies test and support this hypothesis. First, we use a custom smartphone application to repeatedly record participants’ (n = 1166) current social context and the importance they afforded moral values. Results show people rate moral values as more important when in the presence of close others, and this effect is stronger for binding than individualizing values—an effect that replicates in a large preregistered online sample (n = 2016). A lab study (n = 390) and two preregistered online experiments (n = 580 and n = 752) provide convergent evidence that people afford binding, but not individualizing, values more importance when in the real or imagined presence of close others. Our results suggest people selectively activate different moral values according to the demands of the situation, and show how the mere presence of others can affect moral thinking.
Tumor-associated autoantibodies from mouse breast cancer models are found in serum of breast cancer patients
Authors: Stanton Sasha E. , Gad Ekram , Ramos Erik , Corulli Lauren , Annis James , Childs Jennifer , Katayama Hiroyuki , Hanash Samir , Marks Jeffrey , Disis Mary L.
Published: May 2021

B cell responses to tumor antigens occur early in breast tumors and may identify immunogenic drivers of tumorigenesis. Sixty-two candidate antigens were identified prior to palpable tumor development in TgMMTV-neu and C3(1)Tag transgenic mouse mammary tumor models. Five antigens (VPS35, ARPC2, SERBP1, KRT8, and PDIA6) were selected because their decreased expression decreased survival in human HER2 positive and triple negative cell lines in a siRNA screen. Vaccination with antigen-specific epitopes, conserved between mouse and human, inhibited tumor growth in both transgenic mouse models. Increased IgG autoantibodies to the antigens were elevated in serum from women with ductal carcinoma in situ (DCIS) and invasive breast cancer (IBC). The autoantibodies differentiated women with DCIS from control with AUC 0.93 (95% CI 0.88–0.98, p < 0.0001). The tumor antigens identified early in the development of breast cancer in mouse mammary tumor models were conserved in human disease, and potentially identify early diagnostic markers in human breast tumors.
Randomized trial of weight loss on circulating ghrelin levels among breast cancer survivors
Authors: Puklin Leah , Cartmel Brenda , Harrigan Maura , Lu Lingeng , Li Fang-yong , Sanft Tara , Irwin Melinda L.
Published: May 2021

Obesity among breast cancer survivors is associated with increased risk for recurrence and mortality. The hormone ghrelin plays a role in initiating appetite and thus regulating body weight. This study aims to determine the effect of a lifestyle intervention on ghrelin levels in breast cancer survivors with a body mass index (BMI) ≥ 25 kg/m2. The Lifestyle, Exercise, and Nutrition (LEAN) study was a 6-month randomized trial, examining the effectiveness of a weight loss intervention versus usual care in 151 breast cancer survivors with BMI ≥ 25 kg/m2. Ghrelin was measured in fasting baseline and 6-month blood samples. Baseline associations between ghrelin, body composition, and blood biomarkers were examined. Six-month change in ghrelin was compared between study arms. Ghrelin measurements were available for 149 women. At baseline, ghrelin was correlated with age (r = 0.28, p < 0.001) and inversely correlated with weight (r = −0.18, p = 0.03), lean body mass (r = −0.18, p = 0.02), and leptin (r = −0.18, p = 0.03). Over 6 months, ghrelin increased by 144 pg/mL (7.2%) in the intervention and decreased by 466 pg/mL (32.5%) in the usual care (p = 0.07). Among all women, greater weight loss was associated with an increase in ghrelin (p = 0.01). These findings indicate that weight loss, achieved through a lifestyle intervention, is associated with higher ghrelin levels in breast cancer survivors which may be informative for developing sustainable weight loss programming for this population. Future research should investigate the long term impacts of lifestyle interventions on ghrelin levels in the context of weight maintenance and weight regain.
Field studies on breeding sites of Culicoides Latreille (Diptera: Ceratopogonidae) in agriculturally used and natural habitats
Authors: Kameke Daniela , Kampen Helge , Wacker Alexander , Werner Doreen
Published: May 2021

Culicoides are vectors of pathogens mainly of veterinary importance. To establish targeted vector control measures, it is paramount to comprehend the ecological factors determining their distribution. Therefore, we used emergence traps to sample eight biotopes and assess their potential as breeding sites. Part one of the study investigates agricultural habitats, part two compares four biotopes of a forest-dominated area with less anthropogenic influence, including a physicochemical analysis of soil moisture, pH value and organic content. Thirteen culicoid species were collected, with a strong dominance of the Obsoletus Complex on meadows, and with Culicoides punctatus (Meigen), Culicoides pictipennis (Staeger) and the Obsoletus Complex, to be the most abundant species in the natural habitats. Several co-existing species were found, some of them not having been described before. Our results suggest that ungrazed meadows seem unsuitable as breeding sites. Only the influence of livestock creates adequate conditions for certain midge species. The alder on fen site contained most culicoid species with the highest species diversity. Our study clearly indicates that knowledge of species-specific preferences for environmental habitat conditions (choice of breeding site) in connection to soil conditions is crucial to understand the biology and phenology of midges and their role as vectors of pathogens.
Intra-host evolutionary dynamics of the hepatitis C virus among people who inject drugs
Authors: Montoya Vincent , Howe Anita Y. M. , Dong Weiyan Y. , Dong Winnie , Brumme Chanson J. , Olmstead Andrea D. , Hayashi Kanna , Richard Harrigan P. , Joy Jeffrey B.
Published: May 2021

Most individuals chronically infected with hepatitis C virus (HCV) are asymptomatic during the initial stages of infection and therefore the precise timing of infection is often unknown. Retrospective estimation of infection duration would improve existing surveillance data and help guide treatment. While intra-host viral diversity quantifications such as Shannon entropy have previously been utilized for estimating duration of infection, these studies characterize the viral population from only a relatively short segment of the HCV genome. In this study intra-host diversities were examined across the HCV genome in order to identify the region most reflective of time and the degree to which these estimates are influenced by high-risk activities including those associated with HCV acquisition. Shannon diversities were calculated for all regions of HCV from 78 longitudinally sampled individuals with known seroconversion timeframes. While the region of the HCV genome most accurately reflecting time resided within the NS3 gene, the gene region with the highest capacity to differentiate acute from chronic infections was identified within the NS5b region. Multivariate models predicting duration of infection from viral diversity significantly improved upon incorporation of variables associated with recent public, unsupervised drug use. These results could assist the development of strategic population treatment guidelines for high-risk individuals infected with HCV and offer insights into variables associated with a likelihood of transmission.
Use of the heads-up NGENUITY 3D Visualization System for vitreoretinal surgery: a retrospective evaluation of outcomes in a French tertiary center
Authors: Kantor Pierre , Matonti Frédéric , Varenne Fanny , Sentis Vanessa , Pagot-Mathis Véronique , Fournié Pierre , Soler Vincent
Published: May 2021

Heads-up three-dimensional (3D) surgical visualization systems allow ophthalmic surgeons to replace surgical microscope eyepieces with high-resolution stereoscopic cameras transmitting an image to a screen. We investigated the effectiveness and safety of the heads-up NGENUITY 3D Visualization System in a retrospective evaluation of 241 consecutive vitreoretinal surgeries performed by the same surgeon using conventional microscopy (CM group) over a 1-year period versus the NGENUITY System (3D group) over a consecutive 1-year period. We included for study vitreoretinal surgeries for treatment of retinal detachment (RD) (98 surgeries), macular hole (MH) (48 surgeries), or epiretinal membrane (ERM) (95 surgeries). A total of 138 and 103 eyes were divided into 3D and CM groups, respectively. We found no differences in 3-month postoperative rates of recurrence of RD (10% versus 18%, p = 0.42), MH closure (82% versus 88%, p = 0.69), or decrease in central macular thickness of ERMs (134 ± 188 µm versus 115 ± 105 µm, p = 0.57) between the 3D and CM groups, respectively. Surgery durations and visual prognosis were also similar between both groups. We consolidate that the NGENUITY System is comparable in terms of visual and anatomical outcomes, giving it perspectives for integration into future robotized intervention.
Multi-step screening of neoantigens’ HLA- and TCR-interfaces improves prediction of survival
Authors: Richard Guilhem , De Groot Anne S. , Steinberg Gary D. , Garcia Tzintzuni I. , Kacew Alec , Ardito Matthew , Martin William D. , Berdugo Gad , Princiotta Michael F. , Balar Arjun V. , Sweis Randy F.
Published: May 2021

Improvement of risk stratification through prognostic biomarkers may enhance the personalization of cancer patient monitoring and treatment. We used Ancer, an immunoinformatic CD8, CD4, and regulatory T cell neoepitope screening system, to perform an advanced neoantigen analysis of genomic data derived from the urothelial cancer cohort of The Cancer Genome Atlas. Ancer demonstrated improved prognostic stratification and five-year survival prediction compared to standard analyses using tumor mutational burden or neoepitope identification using NetMHCpan and NetMHCIIpan. The superiority of Ancer, shown in both univariate and multivariate survival analyses, is attributed to the removal of neoepitopes that do not contribute to tumor immunogenicity based on their homology with self-epitopes. This analysis suggests that the presence of a higher number of unique, non-self CD8- and CD4-neoepitopes contributes to cancer survival, and that prospectively defining these neoepitopes using Ancer is a novel prognostic or predictive biomarker.
First comprehensive quantification of annual land use/cover from 1990 to 2020 across mainland Vietnam
Authors: Phan Duong Cao , Trung Ta Hoang , Truong Van Thinh , Sasagawa Taiga , Vu Thuy Phuong Thi , Bui Dieu Tien , Hayashi Masato , Tadono Takeo , Nasahara Kenlo Nishida
Published: May 2021

Extensive studies have highlighted a need for frequently consistent land cover information for interdisciplinary studies. This paper proposes a comprehensive framework for the automatic production of the first Vietnam-wide annual land use/land cover (LULC) data sets (VLUCDs) from 1990 to 2020, using available remotely sensed and inventory data. Classification accuracies ranged from 85.7 ± 1.3 to 92.0 ± 1.2% with the primary dominant LULC and 77.6 ± 1.2% to 84.7 ± 1.1% with the secondary dominant LULC. This confirmed the potential of the proposed framework for systematically long-term monitoring LULC in Vietnam. Results reveal that despite slight recoveries in 2000 and 2010, the net loss of forests (19,940 km2) mainly transformed to croplands over 30 years. Meanwhile, productive croplands were converted to urban areas, which increased approximately ten times. A threefold increase in aquaculture was a major driver of the wetland loss (1914 km2). The spatial–temporal changes varied, but the most dynamic regions were the western north, the southern centre, and the south. These findings can provide evidence-based information on formulating and implementing coherent land management policies. The explicitly spatio-temporal VLUCDs can be benchmarks for global LULC validation, and utilized for a variety of applications in the research of environmental changes towards the Sustainable Development Goals.
Co-incorporation of manure and inorganic fertilizer improves leaf physiological traits, rice production and soil functionality in a paddy field
Authors: Iqbal Anas , He Liang , Ali Izhar , Ullah Saif , Khan Aziz , Akhtar Kashif , Wei Shangqin , Fahad Shah , Khan Rayyan , Jiang Ligeng
Published: May 2021

The combined use of organic manure and chemical fertilizer (CF) is considered to be a good method for sustaining high crop yields and improving soil quality. We performed a field experiment in 2019 at the research station of Guanxi University, to investigate the effects of cattle manure (CM) and poultry manure (PM) combined with CF on soil physical and biochemical properties, rice dry matter (DM) and nitrogen (N) accumulation and grain yield. We also evaluated differences in pre-and post-anthesis DM and N accumulation and their contributions to grain yield. The experiment consisted of six treatments: no N fertilizer (T1), 100% CF (T2), 60% CM + 40% CF (T3), 30% CM + 70% CF (T4), 60% PM + 40% CF (T5), and 30% PM + 70% CF (T6). All CF and organic manure treatments provided a total N of 150 kg ha−1. Results showed that the treatment T6increased leaf net photosynthetic rate (Pn) by 11% and 13%, chlorophyll content by 13% and 15%, total biomass by 9% and 11% and grain yield by 11% and 17% in the early and late season, respectively, compared with T2. Similarly, the integrated manure and CF treatments improved post-antheis DM accumulation and soil properties, such as bulk density, organic carbon, total N, microbial biomass carbon (MBC) and microbial biomass nitrogen (MBN) relative to the CF-only treatments. Interestingly, increases in post-anthesis DM and N accumulation were further supported by enhanced leafPnand activity of N-metabolizing enzyme during the grain-filling period. Improvement inPnand N-metabolizing enzyme activity were due to mainly improved soil quality in the combined manure and synthetic fertilizer treatments. Redundancy analysis (RDA) showed a strong relationship between grain yield and soil properties, and a stronger relationship was noted with soil MBC and MBN. Conclusively, a combination of 30% N from PM or CM with 70% N from CF is a promising option for improving soil quality and rice yield.
Tunnelling times, Larmor clock, and the elephant in the room
Authors: Sokolovski D. , Akhmatskaya E.
Published: May 2021

A controversy surrounding the “tunnelling time problem” stems from the seeming inability of quantum mechanics to provide, in the usual way, a definition of the duration a particle is supposed to spend in a given region of space. For this reason, the problem is often approached from an “operational” angle. Typically, one tries to mimic, in a quantum case, an experiment which yields the desired result for a classical particle. One such approach is based on the use of a Larmor clock. We show that the difficulty with applying a non-perturbing Larmor clock in order to “time” a classically forbidden transition arises from the quantum Uncertainty Principle. We also demonstrate that for this reason a Larmor time (in fact, any Larmor time) cannot be interpreted as a physical time interval. We provide a theoretical description of the quantities measured by the clock.
Effect of heat input on interfacial characterization of the butter joint of hot-rolling CP-Ti/Q235 bimetallic sheets by Laser + CMT
Authors: Zhu Z. Y. , Liu Y. L. , Gou G. Q. , Gao W , Chen J.
Published: May 2021

Composite structures made of 2 mm-thick titanium and 10 mm-thick carbon steel are widely used in infrastructures such as long-distance gas transportation. However, cracking, which is caused by intermetallic compounds (ICs), is a dominate failure mode in welds of this structure. Thus, a common way to improve the in-service life of is reduce the number of ICs. In this paper, we employ a novel hybrid welding method to fabricate composite structures of TA2 titanium and Q235 carbon steel. Specifically, Ti and carbon steel is welded by laser and double Cold Metal Transfer (CMT) welding, respectively. The microstructure near the interface of Ti and steel is then examined using SEM, EBSD, EDS, with emphasis on the ICs in terms of chemical elements and morphologies. Results show that FeTi and Fe2Ti are the main ICs near the interface, and responsible for the failure of the welds. The effect of welding heat input on the formation of ICs is investigated as well. Results show that ICs are smaller when the heat input is low. Under low heat input circumstance, the tensile strength of the weld can reach up to 420 MPa.
Experimentally and theoretically approaches for disperse red 60 dye adsorption on novel quaternary nanocomposites
Authors: Soliman N. K. , Moustafa A. F. , El-Mageed H. R. Abd , Abdel-Gawad Omima F. , Elkady Esraa T. , Ahmed Sayed A. , Mohamed Hussein S.
Published: May 2021

A comprehensive study that combined both experimental and computational experiments was performed to evaluate the usage of organo-metal oxide nanocomposite for the elimination of disperse red 60 dye (DR) from aqueous solutions. Chitosan was modified by Schiff base to form nanoneedles chitosan-4-chloroacetophenone derivative. The derivatives were then impregnated with CeO2–CuO–Fe2O3 or CeO2–CuO–Al2O3 metal oxides to prepare a novel quarternary organo-metal oxide nanocomposite. The novel nanocomposite, chitosan-4-chloroacetophenone/CeO2–CuO–Fe2O3 (CF) and chitosan-4-chloroacetophenone/CeO2–CuO–Al2O3 (CA) are cheap and effective nano adsorbents that can be used for the uptake of DR from aqueous solution. The CF and CA nano-composites were characterized using different techniques. Moreover, the effect of adsorption parameters (initial DR concentration, time of contact, pH, temperature, and adsorbent mass) as well as CA and CF reusability tests were performed. Langmuir adsorption isotherm and pseudo-second-order kinetics models were best fitted with the adsorption process. The maximum amount of DR adsorbed was 100 mg/g on CF and CA at pH 2 and 4, respectively with a physical spontaneous, and exothermic adsorption process. Monte Carlo (MC) simulation studies indicated the adsorption of DR molecule on the CF and CA surfaces following a parallel mode in most of all studied configurations, confirming the strong interactions between the DR and surfaces atoms of CF and CA. The molecular structure analysis of DR dye adsorbed on the surface of CF and CA indicated that the adsorption process related to Van der Waals dispersion force. Consequently, this helps to trap DR dye molecules on the surface of CF and CA (i.e., physical adsorption), which supports our experimental results.
Semiparametric model selection for identification of environmental covariates related to adult groundfish catches and weights
Authors: Correia Hannah E.
Published: May 2021

Ecologists and fisheries managers are interested in monitoring economically important marine fish species and using this data to inform management strategies. Determining environmental factors that best predict changes in these populations, particularly under rapid climate change, are a priority. I illustrate the application of the least squares-based spline estimation and group LASSO (LSSGLASSO) procedure for selection of coefficient functions in single index varying coefficient models (SIVCMs) on an ecological data set that includes spatiotemporal environmental covariates suspected to play a role in the catches and weights of six groundfish species. Temporal trends in variable selection were apparent, though the selection of variables was largely unrelated to common North Pacific climate indices. These results indicate that the strength of an environmental variable’s effect on a groundfish population may change over time, and not necessarily in-step with known low-frequency patterns of ocean-climate variability commonly attributable to large-scale regime shifts in the North Pacific. My application of the LSSGLASSO procedure for SIVCMs to deep water species using environmental data from various sources illustrates how variable selection with a flexible model structure can produce informative inference for remote and hard-to-reach animal populations.
Canonical Hamiltonian ensemble representation of dephasing dynamics and the impact of thermal fluctuations on quantum-to-classical transition
Authors: Chen Hong-Bin , Chen Yueh-Nan
Published: May 2021

An important mathematical tool for studying open quantum system theory, which studies the dynamics of a reduced system, is the completely positive and trace-preserving dynamical linear map parameterized by a special parameter-time. Counter-intuitively, akin to the Fourier transform of a signal in time-sequence to its frequency distribution, the time evolution of a reduced system can also be studied in the frequency domain. A recent proposed idea which studies the representation of dynamical processes in the frequency domain, referred to as canonical Hamiltonian ensemble representation (CHER), proved its capability of characterizing the noncalssical traits of the dynamics. Here we elaborate in detail the theoretical foundation within a unified framework and demonstrate several examples for further studies of its properties. In particular, we find that the thermal fluctuations are clearly manifested in the manner of broadening CHER, and consequently rendering the CHER less nonclassical. We also point out the discrepancy between the notions of nonclassicality and non-Markovianity, show multiple CHERs beyond pure dephasing, and, finally, to support the practical viability, propose an experimental realization based upon the free induction decay measurement of nitrogen-vacancy center in diamond.
A novel thermostable beetle luciferase based cytotoxicity assay
Authors: Choi Sunju , Matta Hittu , Gopalakrishnan Ramakrishnan , Natarajan Venkatesh , Gong Songjie , Jeronimo Alberto , Kuo Wei-Ying , Bravo Bryant , Chaudhary Preet M.
Published: May 2021

Cytotoxicity assays are essential for the testing and development of novel immunotherapies for the treatment of cancer. We recently described a novel cytotoxicity assay, termed the Matador assay, which was based on marine luciferases and their engineered derivatives. In this study, we describe the development of a new cytotoxicity assay termed ‘Matador-Glo assay’ which takes advantage of a thermostable variant of Click Beetle Luciferase (Luc146-1H2). Matador-Glo assay utilizes Luc146-1H2 and D-luciferin as the luciferase-substrate pair for luminescence detection. The assay involves ectopic over-expression of Luc146-1H2 in the cytosol of target cells of interest. Upon damage to the membrane integrity, the Luc146-1H2 is either released from the dead and dying cells or its activity is preferentially measured in dead and dying cells. We demonstrate that this assay is simple, fast, specific, sensitive, cost-efficient, and not labor-intensive. We further demonstrate that the Matador-Glo assay can be combined with the marine luciferase-based Matador assay to develop a dual luciferase assay for cell death detection. Finally, we demonstrate that the Luc146-1H2 expressing target cells can also be used for in vivo bioluminescence imaging applications.
Sustained release of usnic acid from graphene coatings ensures long term antibiofilm protection
Authors: Pandit Santosh , Rahimi Shadi , Derouiche Abderahmane , Boulaoued Athmane , Mijakovic Ivan
Published: May 2021

Protecting surfaces from bacterial colonization and biofilm development is an important challenge for the medical sector, particularly when it comes to biomedical devices and implants that spend longer periods in contact with the human body. A particularly difficult challenge is ensuring long-term protection, which is usually attempted by ensuring sustained release of antibacterial compounds loaded onto various coatings. Graphene have a considerable potential to reversibly interact water insoluble molecules, which makes them promising cargo systems for sustained release of such compounds. In this study, we developed graphene coatings that act as carriers capable of sustained release of usnic acid (UA), and hence enable long-term protection of surfaces against colonization by bacterial pathogens Staphylococcus aureus and Staphylococcus epidermidis. Our coatings exhibited several features that made them particularly effective for antibiofilm protection: (i) UA was successfully integrated with the graphene material, (ii) a steady release of UA was documented, (iii) steady UA release ensured strong inhibition of bacterial biofilm formation. Interestingly, even after the initial burst release of UA, the second phase of steady release was sufficient to block bacterial colonization. Based on these results, we propose that graphene coatings loaded with UA can serve as effective antibiofilm protection of biomedical surfaces.
Interaction among sea urchins in response to food cues
Authors: Sun Jiangnan , Zhao Zihe , Zhao Chong , Yu Yushi , Ding Peng , Ding Jingyun , Yang Mingfang , Chi Xiaomei , Hu Fangyuan , Chang Yaqing
Published: May 2021

Interaction among sea urchins remains largely uninvestigated, although the aggregation of sea urchins is common. In the present study, 1, 15 and 30 sea urchins Strongylocentrotus intermedius (11.06 ± 0.99 mm in test diameter) were placed in a 1 m2 circular tank, respectively. Movement behaviors were recorded for 12 min to investigate potential interactions among sea urchins. After the 12-min control period, we added food cues into the tank and recorded the changes in sea urchins’ behaviors. For the first time, we here quantified the interactions among sea urchins in laboratory and found that the interactions varied with food cues and with different densities. The sea urchins dispersed in random directions after being released. There was no significant difference in the movement speed and the displacement of sea urchins among the three density groups (1, 15 and 30 ind/m2). The interaction occurred when sea urchins randomly contacted with the conspecifics and slowed down the movement speed. The speed of sea urchins after physical contacts decreased by an average of 40% in the density of 15 ind/m2 and 17% in the density of 30 ind/m2. This interaction resulted in significantly higher randomness in the movement direction and lower movement linearity in 15 and 30 ind/m2 than in 1 ind/m2. After the introduction of food cues, the movement speed, displacement and dispersal distance of sea urchin groups decreased significantly in all the three densities. The dispersal distance and expansion speed of sea urchins were significantly lower in 30 ind/m2 than those in 15 ind/m2. The present study indicates that the interaction among sea urchins limits the movement of individual sea urchin and provides valuable information into how large groups of sea urchins are stable in places where food is plentiful.
Identification of linear epitopes on the flagellar proteins of Clostridioides difficile
Authors: Razim A. , Pacyga K. , Naporowski P. , Martynowski D. , Szuba A. , Gamian A. , Górska S.
Published: May 2021

Clostridioides difficile (C. difficile) is an opportunistic anaerobic bacterium that causes severe diseases of the digestive tract of humans and animals. One of the possible methods of preventing C. difficile infection is to develop a vaccine. The most promising candidates for vaccine antigens are the proteins involved in the adhesion phenomena. Among them, the FliC and FliD are considered to be suitable candidates. In this paper, the FliC and FliD protein polypeptide epitopes were mapped in silico and by using PEPSCAN procedure. We identified four promising epitopes: 117QRMRTLS123, 205MSKAG209 of FliC and 226NKVAS230, 306TTKKPKD312 of FliD protein. We showed that 117QRMRTLS123 sequence is not only located in TLR5-binding and activating region, as previously shown, but forms an epitope recognized by C. difficile-infected patients’ antibodies. 205MSKAG209 is a C. difficile-unique, immunogenic sequence that forms an exposed epitope on the polymerized flagella structure which makes it a suitable vaccine antigen. 226NKVAS230 and 306TTKKPKD312 are well exposed and possess potential protective properties according to VaxiJen analysis. Our results open the possibility to use these epitopes as suitable anti-C. difficile vaccine antigens.
Hybrid modeling approach for mode-locked laser diodes with cavity dispersion and nonlinearity
Authors: Cuyvers Stijn , Poelman Stijn , Van Gasse Kasper , Kuyken Bart
Published: May 2021

Semiconductor-based mode-locked lasers, integrated sources enabling the generation of coherent ultra-short optical pulses, are important for a wide range of applications, including datacom, optical ranging and spectroscopy. As their performance remains largely unpredictable due to the lack of commercial design tools and the poorly understood mode-locking dynamics, significant research has focused on their modeling. In recent years, traveling-wave models have been favored because they can efficiently incorporate the rich semiconductor physics of the laser. However, thus far such models struggle to include nonlinear and dispersive effects of an extended passive laser cavity, which can play an important role for the temporal and spectral pulse evolution and stability. To overcome these challenges, we developed a hybrid modeling strategy by unifying the traveling-wave modeling technique for the semiconductor laser sections with a split-step Fourier method for the extended passive laser cavity. This paper presents the hybrid modeling concept and exemplifies for the first time the significance of the third order nonlinearity and dispersion of the extended cavity for a 2.6 GHz III–V-on-Silicon mode-locked laser. This modeling approach allows to include a wide range of physical phenomena with low computational complexity, enabling the exploration of novel operating regimes such as chip-scale soliton mode-locking.
Climate drivers of large magnitude snow avalanche years in the U.S. northern Rocky Mountains
Authors: Peitzsch Erich H. , Pederson Gregory T. , Birkeland Karl W. , Hendrikx Jordy , Fagre Daniel B.
Published: May 2021

Large magnitude snow avalanches pose a hazard to humans and infrastructure worldwide. Analyzing the spatiotemporal behavior of avalanches and the contributory climate factors is important for understanding historical variability in climate-avalanche relationships as well as improving avalanche forecasting. We used established dendrochronological methods to develop a long-term (1867–2019) regional avalanche chronology for the Rocky Mountains of northwest Montana using tree-rings from 647 trees exhibiting 2134 avalanche-related growth disturbances. We then used principal component analysis and a generalized linear autoregressive moving average model to examine avalanche-climate relationships. Historically, large magnitude regional avalanche years were characterized by stormy winters with positive snowpack anomalies, with avalanche years over recent decades increasingly influenced by warmer temperatures and a shallow snowpack. The amount of snowpack across the region, represented by the first principal component, is shown to be directly related to avalanche probability. Coincident with warming and regional snowpack reductions, a decline of ~ 14% (~ 2% per decade) in overall large magnitude avalanche probability is apparent through the period 1950–2017. As continued climate warming drives further regional snowpack reductions in the study region our results suggest a decreased probability of regional large magnitude avalanche frequency associated with winters characterized by large snowpacks and a potential increase in large magnitude events driven by warming temperatures and spring precipitation.
Differences in effectiveness and use of laparoscopic surgery in locally advanced colon cancer patients
Authors: Schootman M. , Mutch Matthew , Loux T. , Eberth J. M. , Davidson N. O.
Published: May 2021

Patients with locally advanced colon cancer have worse outcomes. Guidelines of various organizations are conflicting about the use of laparoscopic colectomy (LC) in locally advanced colon cancer. We determined whether patient outcomes of LC and open colectomy (OC) for locally advanced (T4) colon cancer are comparable in all colon cancer patients, T4a versus T4b patients, obese versus non-obese patients, and tumors located in the ascending, descending, and transverse colon. We used data from the 2013–2015 American College of Surgeons’ National Surgical Quality Improvement Program. Patients were diagnosed with nonmetastatic pT4 colon cancer, with or without obstruction, and underwent LC (n = 563) or OC (n = 807). We used a composite outcome score (mortality, readmission, re-operation, wound infection, bleeding transfusion, and prolonged postoperative ileus); length of stay; and length of operation. Patients undergoing LC exhibited a composite outcome score that was 9.5% lower (95% CI − 15.4; − 3.5) versus those undergoing OC. LC patients experienced a 11.3% reduction in postoperative ileus (95% CI − 16.0; − 6.5) and an average of 2 days shorter length of stay (95% CI − 2.9; − 1.0). Patients undergoing LC were in the operating room an average of 13.5 min longer (95% CI 1.5; 25.6). We found no evidence for treatment heterogeneity across subgroups (p > 0.05). Patients with locally advanced colon cancer who receive LC had better overall outcomes and shorter lengths of stay compared with OC patients. LC was equally effective in obese/nonobese patients, in T4a/T4b patients, and regardless of the location of the tumor.
The feasibility of Gazefinder under 12 months of age infants
Authors: Fukushima Shuntaro , Takahashi Tomoo , Tsukamoto Kazuki , Matsumura Misaki , Takigawa Ryo , Sakai Yasuo , Maniwa Sokichi , Murphy Lynne , Taketani Takeshi
Published: May 2021

Eye-tracking to evaluate gaze patterns has developed as an assessment tool for children with autism spectrum disorder (ASD). Gazefinder is one of Eye-tracking devices and few studies have investigated whether it can measure the gaze data of infants under 12 months of age. We conducted a prospective cross-sectional study from April 2019 to March 2020 in a periodic health checkup in Ohchi County, Shimane, Japan. Participants included infants between 4 and 11 months of age who were not suspected the presence of developmental problems. Ninety-three participants’ datapoints were analyzed. The mean age was 6.5 months and mean developmental quotient was 88%. The mean fixation time percentage of all sequences was 81.0% (standard deviation; 4.4), and there was no significant difference in each age group. Infants in all groups showed a significantly higher predilection for eyes than for mouths. There was a positive association of age with human gaze and a negative association with geometric gaze. Moreover, we confirmed that joint attention skills were enhanced in accordance with their growth process. The eye-tracking data were almost corresponding to previous studies’ data of infant with typical development and Gazefinder could be applied to infants starting at 4 months of age.