bluuebunny/crossref_metadata_2025 huggingface dataset:
Tidal Marsh Sediment and Carbon Accretion on a Geomorphologically Dynamic Coastline
Authors: van Ardenne L. B. , Hughes J. F. , Chmura G. L.
Published: October 2021

We examined the sediment profiles, surface accretion rates, and soil carbon (C) accumulation rates of two brackish tidal marshes on Kilbella and Wannock Rivers of the central coast of British Columbia, Canada, a region where such tidal marsh studies are rare. Sediment grain size is variable within these deposits and is a significant predictor of soil C density. The average soil C density of the Kilbella (0.027 ± 0.01 g C cm−³) and the Wannock marsh (0.029 ± 0.007 g C cm−³) are within the range of reported global averages. Compared to global estimates, the depth weighted mean rates of soil C accumulation are low, between 29 and 50 g C m−2 year−1, although high sectional rates (up to 490 ± 230 g C m−³ year−1) occur in deeper segments of the marsh profile at Kilbella. Modern accretion rates are below moderate to high sea level rise scenarios. The Kilbella marsh contains sand layers from periods of mass sedimentation events (landslides and tsunamis), which provide the marsh with elevation capital that can be critical to its sustainability. The Kilbella profile demonstrates that variation in carbon density with depth cannot be predicted in marshes on geomorphologically dynamic coasts.
Impact of Surface Roughness on Evaporation in 2D Micromodels
Authors: Ding Yi , Geistlinger Helmut
Published: October 2021

Evaporation—a key process for water exchange between soil and atmosphere—is controlled by internal water fluxes and surface vapor fluxes. Recent studies demonstrated that the dynamics of the water flow in pore corners and thick‐film flow on the rough pore‐solid interface determine the time behavior of the evaporation rate. A comprehensive experimental study of the combined effect of corner flow (CF) and thick‐film flow (TFF) on evaporation is lacking. Herein, we present a comparative micromodel study of the evaporation process using 2D‐porous media, which exhibit the same stochastic pore structure, but different degree of surface roughness (silicon micromodels with smooth surface and glass‐ceramic micromodels with rough surface). Our study proves both experimentally and theoretically that surface roughness and wettability play a key role for the time and temperature behaviors of the evaporation process. We found a similar behavior up to 42°C regarding the mass loss as a function of time in stage‐2 and a transition to linear t behavior for higher temperatures (61°C) with a high statistical significance (regression coefficients near 1) for both micromodels. Our experimental results elucidate the strong temporal correlation between mass loss and geometric pattern of the unsaturated CF and TFF region. Partial wetting in silicon micromodels causes a weak driving force for CF, whereas complete wetting in glass‐ceramic micromodels causes a strong driving force for TFF. For a consistent description of the time‐dependent mass loss and geometry of the CF/TFF region, the fractality of the evaporation front must be considered. Based on our data, we estimate the film thickness and discover some interesting film‐thinning effect with increasing temperature.
SPDEF suppresses head and neck squamous cell carcinoma progression by transcriptionally activating NR4A1
Authors: Wang Yanting , Ren Xianyue , Li Weiyu , Cao Ruoyan , Liu Suyang , Jiang Laibo , Cheng Bin , Xia Juan
Published: October 2021

SAM pointed domain containing E26 transformation-specific transcription factor (SPDEF) plays dual roles in the initiation and development of human malignancies. However, the biological role of SPDEF in head and neck squamous cell carcinoma (HNSCC) remains unclear. In this study, the expression level of SPDEF and its correlation with the clinical parameters of patients with HNSCC were determined using TCGA-HNSC, GSE65858, and our own clinical cohorts. CCK8, colony formation, cell cycle analysis, and a xenograft tumor growth model were used to determine the molecular functions of SPDEF in HNSCC. ChIP-qPCR, dual luciferase reporter assay, and rescue experiments were conducted to explore the potential molecular mechanism of SPDEF in HNSCC. Compared with normal epithelial tissues, SPDEF was significantly downregulated in HNSCC tissues. Patients with HNSCC with low SPDEF mRNA levels exhibited poor clinical outcomes. Restoring SPDEF inhibited HNSCC cell viability and colony formation and induced G0/G1 cell cycle arrest, while silencing SPDEF promoted cell proliferation in vitro. The xenograft tumor growth model showed that tumors with SPDEF overexpression had slower growth rates, smaller volumes, and lower weights. SPDEF could directly bind to the promoter region of NR4A1 and promoted its transcription, inducing the suppression of AKT, MAPK, and NF-κB signaling pathways. Moreover, silencing NR4A1 blocked the suppressive effect of SPDEF in HNSCC cells. Here, we demonstrate that SPDEF acts as a tumor suppressor by transcriptionally activating NR4A1 in HNSCC. Our findings provide novel insights into the molecular mechanism of SPDEF in tumorigenesis and a novel potential therapeutic target for HNSCC.
Increased risk of near term global warming due to a recent AMOC weakening
Authors: Bonnet Rémy , Swingedouw Didier , Gastineau Guillaume , Boucher Olivier , Deshayes Julie , Hourdin Frédéric , Mignot Juliette , Servonnat Jérôme , Sima Adriana
Published: October 2021

Some of the new generation CMIP6 models are characterised by a strong temperature increase in response to increasing greenhouse gases concentration1. At first glance, these models seem less consistent with the temperature warming observed over the last decades. Here, we investigate this issue through the prism of low-frequency internal variability by comparing with observations an ensemble of 32 historical simulations performed with the IPSL-CM6A-LR model, characterized by a rather large climate sensitivity. We show that members with the smallest rates of global warming over the past 6-7 decades are also those with a large internally-driven weakening of the Atlantic Meridional Overturning Circulation (AMOC). This subset of members also matches several AMOC observational fingerprints, which are in line with such a weakening. This suggests that internal variability from the Atlantic Ocean may have dampened the magnitude of global warming over the historical era. Taking into account this AMOC weakening over the past decades means that it will be harder to avoid crossing the 2 °C warming threshold.
A three-tiered colloidosomal microreactor for continuous flow catalysis
Authors: Wu Hua , Du Xuanlin , Meng Xiaohui , Qiu Dong , Qiao Yan
Published: October 2021

Integrative colloidosomes with hierarchical structure and advanced function may serve as biomimetic microreactors to carry out catalytic reactions by compartmentalizing biological species within semipermeable membranes. Despite of recent progress in colloidosome design, integration of biological and inorganic components into tiered structures to tackle the remaining challenges of biocatalysis is highly demanded. Here, we report a rational design of three-tiered colloidosomes via the Pickering emulsion process. The microreactor consists of crosslinked amphiphilic silica-polymer hybrid nanoparticles as the semipermeable shell, an enzyme-incorporated catalytic sub-layer, and a partially-silicified adsorptive lumen. By leveraging confinement and enrichment effect, we demonstrate the acceleration of lipase-catalyzed ester hydrolysis within the microcompartment of organic-inorganic hybrid colloidosomes. The catalytic colloidosomes are further assembled into a closely packed column for enzymatic reactions in a continuous flow format with enhanced reaction rates. The three-tiered colloidosomes provide a reliable platform to integrate functional building blocks into a biomimetic compartmentalized microreactor with spatially controlled organization and high-performance functions.
Importance of untested infectious individuals for interventions to suppress COVID-19
Authors: Pérez-Reche Francisco J. , Forbes Ken J. , Strachan Norval J. C.
Published: October 2021

The impact of the extent of testing infectious individuals on suppression of COVID-19 is illustrated from the early stages of outbreaks in Germany, the Hubei province of China, Italy, Spain and the UK. The predicted percentage of untested infected individuals depends on the specific outbreak but we found that they typically represent 60–80% of all infected individuals during the early stages of the outbreaks. We propose that reducing the underlying transmission from untested cases is crucial to suppress the virus. This can be achieved through enhanced testing in combination with social distancing and other interventions that reduce transmission such as wearing face masks. Once transmission from silent carriers is kept under control by these means, the virus could have been fully suppressed through fast isolation and contact tracing of tested cases.
Comparative of meibomian gland morphology in patients with evaporative dry eye disease versus non-dry eye disease
Authors: Crespo-Treviño Ricaurte Ramiro , Salinas-Sánchez Anna Karen , Amparo Francisco , Garza-Leon Manuel
Published: October 2021

Many recent studies have showed that morphological changes are one of the key signs of meibomian gland disease (MGD). These changes can be seen even before symptom onset, potentially underestimating the prevalence of MGD; however, until now, there is no conclusive information about the impact of meibomian gland (MG) morphology in tear film physiology and disease. This study aimed to investigate the prevalence of anatomical and morphological MG alterations between patients with evaporative dry eye disease (DED) and healthy controls. Retrospective chart review of seventy-five patients with evaporative DED and healthy individuals who had dry eye assessments included Ocular Surface Disease Index questionnaire, meibum quality, meibum expressibility, lid margin abnormality, ocular staining, non-invasive tear film break-up time, and meibography. We did not find significant differences in MG alterations in the upper lid between healthy and DED subjects. Patients with evaporative DED presented MG alterations in the lower lid more frequently than healthy subjects (54.8 vs. 30.3%; p = 0.03). The presence of shortened glands was the only MG alteration that was more prevalent in the lower lid in dry-eye patients than in healthy subjects (p < 0.05). Subjects with evaporative DED presented more alterations in the lower lid than healthy subjects.
Tyrosinase-mediated synthesis of larvicidal active 1,5-diphenyl pent-4-en-1-one derivatives against Culex quinquefasciatus and investigation of their ichthyotoxicity
Authors: Chidambaram SathishKumar , Ali Daoud , Alarifi Saud , Gurusamy Raman , Radhakrishnan SurendraKumar , Akbar Idhayadhulla
Published: October 2021

1,5-diphenylpent-4-en-1-one derivatives were synthesised using the grindstone method with Cu(II)-tyrosinase used as a catalyst. This method showed a high yield under mild reaction conditions. The synthesised compounds were identified by FTIR, 1H NMR, 13C NMR, mass spectrometry, and elemental analysis. In this study, a total of 17 compounds (1a–1q) were synthesised, and their larvicidal and antifeedant activities were evaluated. Compound 1i (1-(5-oxo-1,5-diphenylpent-1-en-3-yl)-3-(3-phenylallylidene)thiourea) was notably more active (LD50: 28.5 µM) against Culex quinquefasciatus than permethrin(54.6 µM) and temephos(37.9 µM), whereas compound 1i at 100 µM caused 0% mortality in Oreochromis mossambicus within 24 h in an antifeedant screening, with ichthyotoxicity determined as the death ratio (%) at 24 h. Compounds 1a, 1e, 1f, 1j, and 1k were found to be highly toxic, whereas 1i was not toxic in antifeedant screening. Compound 1i was found to possess a high larvicidal activity against C. quinquefasciatus and was non-toxic to non-target aquatic species. Molecular docking studies also supported the finding that 1i is a potent larvicide with higher binding energy than the control (− 10.0 vs. − 7.6 kcal/mol) in the 3OGN protein. Lead molecules are important for their larvicidal properties and application as insecticides.
A reconfigurable intelligent surface with integrated sensing capability
Authors: Alamzadeh Idban , Alexandropoulos George C. , Shlezinger Nir , Imani Mohammadreza F.
Published: October 2021

Reconfigurable reflective surfaces can alter the propagation environment to improve wireless communication and power transfer. Paramount to this operation—which has attracted much attention recently—is the assumption that the reflective surface has prior knowledge of the propagation environment, for example, the direction/location of the transmitter and the intended receiver(s). To address this need, we propose a reconfigurable reflective metasurface with integrated sensing capabilities. By modifying the tunable meta-atoms constituting the metasurface, we couple small portions of the incident wave to an array of sensing waveguides. As an illustrative example, we demonstrate the ability to use the sampled incident wave to detect its angle of arrival. In addition, we propose and numerically demonstrate the possibility to reduce the required sensors, i.e., the number of radio frequency (RF) chains needed to acquire the sensed signals, by leveraging the inherent metasurface’s tunable multiplexing capability. A reconfigurable reflective metasurface with integrated sensing capabilities can benefit wireless communications, wireless power transfer, RF sensing, and smart sensors.
Design, synthesis, structural, spectral, and redox properties and phenoxazinone synthase activity of tripodal pentacoordinate Mn(ii) complexes with impressive turnover numbers
Authors: Kumbhakar Sadananda , Giri Bishnubasu , Muley Arabinda , Karumban Kalai Selvan , Maji Somnath
Published: October 2021

Two mononuclear pentacoordinate manganese complexes with the molecular framework [MnII(Ln)Cl]Cl have been synthesized and thoroughly characterized. Under ambient conditions, both the complexes show excellent phenoxazinone synthase activity.
Coordination environment engineering on nickel single-atom catalysts for CO2 electroreduction
Authors: Ma Mengbo , Li Fuhua , Tang Qing
Published: October 2021

The correlation between the coordination environment and the activity/selectivity of B/C/N co-coordinated Ni single atom catalysts towards CO2 electroreduction was systematically studied by theory.
Towards advanced aqueous zinc battery by exploiting synergistic effects between crystalline phosphide and amorphous phosphate
Authors: Zhao Shunshun , Qu Guangmeng , Wang Chenggang , Zhang Yujin , Li Chuanlin , Li Xiaojuan , Sun Jie , Leng Jiancai , Xu Xijin
Published: October 2021

The advanced flexible aqueous zinc battery was exploited by using the synergistic effects of crystalline phosphide and amorphous phosphate.
Development of physical, mechanical, antibacterial and cell growth properties of poly(glycerol sebacate urethane) (PGSU) with helping of curcumin and hydroxyapatite nanoparticles
Authors: Fakhri Vafa , Jafari Aliakbar , Shafiei Mir Alireza , Ehteshamfar Mohammad Vahid , Khalighiyan Shima , Hosseini Hadi , Goodarzi Vahabodin , Wurm Frederik R. , Moosazadeh Moghaddam Mehrdad , Khonakdar Hossein Ali
Published: October 2021

Biocompatible and antimicrobial elastomers with controlled hydrophilicity and degradation rate, as well as appropriate stiffness and elasticity, are interesting for biomedical applications, such as regenerative medicine and tissue engineering.
Designing light-driven rotary molecular motors
Authors: Pooler Daisy R. S. , Lubbe Anouk S. , Crespi Stefano , Feringa Ben L.
Published: October 2021

Various families of light-driven rotary molecular motors and the key aspects of motor design are discussed. Comparisons are made between the strengths and weaknesses of each motor. Challenges, applications, and future prospects are explored.
Processing of fast-gelling hydrogel precursors in microfluidics by electrocoalescence of reactive species
Authors: Hauck Nicolas , Neuendorf Talika A. , Männel Max J. , Vogel Lucas , Liu Ping , Stündel Enno , Zhang Yixin , Thiele Julian
Published: October 2021

Controlled electrocoalescence of droplet pairs containing fast-gelling hydrogel precursors is highlighted as a versatile method for processing reactive species into well-defined uniform microgels as well as a special type of anisotropic microgels with a tunable curvatureviadroplet microfluidics.
Aspiration Screening in Motor Neuron Disease: Preliminary Results From Utilization of the Yale Swallow Protocol
Authors: (Focht) Garand Kendrea L. , Suiter Debra M. , Reyes Stephanie , York Justine Dallal , Chen I-Hweii Amy
Published: October 2021

Purpose

Dysphagia is a common symptom experienced by patients with motor neuron disease (MND). The Yale Swallow Protocol (YSP) is a validated screening instrument for identifying patients at risk for aspiration. The purpose of this exploratory cross-sectional, multicenter study was to investigate how the YSP results in identifying aspiration risk in patients with MND in comparison with aspiration observed during a videofluoroscopic swallow study (VFSS).

Method

Participants referred for VFSS as part of clinical management were recruited from four specialized MND clinics. All participants were administered the YSP immediately prior to the VFSS by a speech-language pathologist, with results recorded as pass or fail. Aspiration on VFSS was determined using the Penetration–Aspiration Scale (scores 6–8). A 2 × 2 contingency table was constructed to compare results of YSP with those on VFSS.

Results

Thirty-one patients with MND (13 males, 18 females;
M
age
= 64 ± 12 years) referred for VFSS participated in this study. Of the 22 patients who failed the YSP, interrupted drinking was the most frequent reason (65%). Compared to the VFSS, the YSP yielded a sensitivity of 80%, a specificity of 33%, positive predictive value of 36%, and negative predictive value of 78%.

Conclusions

The YSP is a simple tool and easy to utilize and has a high sensitivity in identifying aspiration risk in amyotrophic lateral sclerosis. A future investigation with a larger sample size is needed to better investigate the utility of YSP as a screening tool for this population.
Achieving the performance of the MMSE receiver with the maximum ratio combiner
Authors: Carrera Diego Fernando , Vargas‐Rosales Cesar , Azpilicueta Leyre , Granda Fausto
Published: October 2021

In this article, we propose a new pilot mapping method to jointly estimate the channel state information of the user while reducing the interference effects of multiuser multicell mobile scenarios. The problem of achieving the wireless performance of the minimum mean square error (MMSE) receiver with the maximum ratio (MR) combiner for massive multiple‐input multiple‐output (MIMO) systems in the frequency bands of 2.5 GHz and 28 GHz is addressed. By transmitting fewer pilots in the uplink communications and arranging those pilots to reduce interuser interference, we can achieve higher spectral efficiency (SE) with the MR and MMSE receivers. Numerical results show significantly fewer floating‐point operations for MIMO processing when the proposed pilot mapping strategy is combined with Kalman filtering estimation and MR processing, achieving an SE comparable to the MMSE receiver.
Application of adaptive chirp mode decomposition on parameter identification of sub/super‐synchronous oscillation signals
Authors: Yang Xiaomei , Li Haoyi , Mei Yubo , Hu Xunyong , Wang Yang , Xiao Xianyong
Published: October 2021

Identifying the parameters of sub/super‐synchronous oscillation (SubSO/SupSO) signals is challenging, because (1) the mode numbers of the oscillation signals are unknown, and (2) the oscillation signals are non‐stationary and noisy. The non‐stationary components need to be accurately identified in order to efficiently suppress SubSO/SupSO. Here, an adaptive chirp mode decomposition (ACMD) method joining a synchroextracting transform (SET) is exploited. First, for detecting the initial instantaneous frequencies (IFs) of SubSO and SupSO, SET is employed to provide time–frequency representations with satisfied energy concentration to ACMD. Second, ACMD is applied to decomposing the main components from the oscillation signal without needing to use the mode numbers, and directly compute the final IFs and instantaneous amplitudes (IAs) for SubSO and SupSO without Hilbert transform. And third, the damping factors of the SubSO and SupSO are further identified with the IAs. The proposed method is evaluated over synthetic signals, simulation data, and real field data from a wind system. Experimental results demonstrate that, compared with the classical signal decomposition‐based identification methods, the proposed method more accurately detects frequencies, amplitudes, and damping factors of SubSO and SupSO components for non‐stationary and noisy signals.
A quick fault location and isolation method for distribution network based on adaptive reclosing
Authors: Zhang Wei , Chang Zhongxue , Zhang Chenhao , Song Guobing , Tan Weibin
Published: October 2021

Feeder automation is important to improve the reliability of power supply for distribution network. Existing voltage‐time feeder automation scheme exists the problems of long fault processing time and the upstream switches of the fault point need to tolerate fault current twice and the upstream sections need to experience two short time power outage. In this paper, a quick fault location and isolation method for distribution network based on adaptive reclosing is proposed. Three key technologies of the strategy are introduced, including a phase segregated switch of the distribution network based on the permanent magnet operating structure, the phase selector based on transient current characteristics, and the temporary fault and permanent fault identification method based on the power frequency voltage characteristics. The proposed strategy can avoid the second impact on upstream switches and power‐off of the upstream section in case of the permanent fault and can effectively shorten the fault processing time.
The Great Slump: Mrk 926 reveals discrete and varying Balmer line satellite components during a drastic phase of decline
Authors: Kollatschny Wolfram , Ochmann Martin W. , Kaspi Shai , Schumacher Claas , Behar Ehud , Chelouche Doron , Horne Keith , Müller Björn , Rafter Stephen E. , Chini Rolf , Haas Martin , Probst Malte A.
Published: October 2021

Aims.Mrk 926 is known to be a highly variable active galactic nucleus. Furthermore, it is known to show very broad line profiles. We intended to study the continuum and line profile variations of this object with high temporal resolution in order to determine its broad-line region structure and to derive its black hole mass.

Methods.We carried out a high-cadence spectroscopic variability campaign of Mrk 926 with the 10m HET telescope, aided by photometricV-band data taken with the C18 telescope at the Wise Observatory, over a period of about five months. We extracted spectroscopic continuum and line light curves, and computed cross-correlation functions (CCFs) as well as velocity-resolved CCFs with respect to the combined spectroscopic and photometricV-band light curve.

Results.The continuum luminosity of Mrk 926 showed a drastic decrease during our campaign. The luminosity dropped to less than 50% of its original luminosity within only 2.5 months. Furthermore, the spectra of Mrk 926 show complex and very broad Balmer line profiles, including outer Balmer satellites ranging from ±5000 to ±13 000 km s−1. The integrated Hα, Hβ, and He Iλ5876 line light curves are delayed relative to the continuum light curve. The Hαand Hβlines show two velocity-delay structures in the central part of their line profile (within ±5000 km s−1), at ∼10 and ∼57 light-days and at ∼5 and ∼48 light-days, respectively. These structures might be interpreted as the upper and lower halves of an ellipse in the velocity-delay plane, which might be the signature of a line-emitting ring, inclined by ∼50° to the line of sight and orbiting the black hole at radii,R, of 33.5 and 26.5 light-days. We determined continuum luminosities, log(λ Lλ/erg s−1), of 43.68–44.13, which are in good agreement with the establishedRBLR − LAGNrelation. Adopting delays of 33.5 and 26.5 days for Hαand Hβ, respectively, we derive a black hole mass of (1.1 ± 0.2)×108 M⊙; this indicates a low Eddington ratio, which decreased from 8 to 3 percent during our campaign. The Balmer satellite components show a higher correlation coefficient with respect to the continuum than the central line profile, and their response to the continuum variations is on the order of only 3 − 5 days. We attribute this to the central line segment and the Balmer satellites having different, spatially distinct regions of origin.
Selective Toxicity Effect of Fatty Acids Omega-3, 6 and 9 Combination
on Glioblastoma Neurons through their Mitochondria
Authors: Seydi Enayatollah , Sadeghi Hadiseh , Ramezani Maral , Mehrpouya Leila , Pourahmad Jalal
Published: October 2021

Glioblastoma (GBM) is one of the most common malignant tumors of the central
nervous system that occurs in the brain and is a deadly disease. Despite the
different approaches to the treatment of this malignancy, the discovery of new
compounds with anti-cancer effects seems necessary. In this study, the selective
toxicity effects of omega 3, 6 and 9 combinations on mitochondria isolated from
U87MG human glioma cells and also human embryonic kidney 293 cells (HEK293) as
normal control were investigated. The results indicated that the omega 3, 6 and
9 combinations significantly reduced succinate dehydrogenase (SDH) activity only
in mitochondria isolated from U87MG human glioma cells. Additionally, exposure
of mitochondria isolated from U87MG human glioma cells to this combination was
associated with a selective increase in the level of reactive oxygen species
(ROS), the collapse of the mitochondrial membrane potential (MMP), mitochondrial
swelling and cytochrome c release. However, these effects were not observed in
mitochondria isolated from HEK293 cells (as a normal group). According to
results, it is proposed that the combination of omega 3, 6 and 9 could induce
toxicity in U87MG human glioma cells through their mitochondria. This
combination can be helpful as a complementary therapy in patients with GBM.
Psychological Problems Experienced by Patients with Bowel Endometriosis Awaiting Surgery
Authors: Ribeiro Helizabet Salomão Abdalla Ayroza , Paiva Andresa Maria Felipe de , Taliberti Beatriz da Costa Porto , Gonçalves Anna Luiza Lobão , Condes Renata Pereira , Ribeiro Paulo Augusto Galvão Ayroza
Published: October 2021

Objective To assess the most common psychological disturbances in women with deep endometriosis and bowel involvement who are waiting surgical treatment and to evaluate what forms of coping are used to solve the problem.

Methods This was a cross-sectional observational study of 40 women diagnosed with deep endometriosis and intestinal symptoms. They completed two questionnaires: one for anxiety and depression (Hospital Anxiety and Depression Scale [ HADS]) and the Scale of Mode of Confronting Problems (EMEP, in the Portuguese acronym).

Results We found that 77.1% of the patients had anxiety and depression, with anxiety being the most prevalent (87.5% of the patients); 90% of the patients used problem-focused and religious introspection as their main modes of confronting problems.

Conclusion In the use of the HADS questionary, two psychological aspects were the most present in women with deep endometriosis awaiting surgical treatment: anxiety and depression. The most used forms of coping to solve the problem were problem-coping and religious practices.
Kinetics and mechanism of catalytic reduction of U(VI) with hydrazine on platinum catalysts in nitric acid media
Authors: Zhang Xiao-teng , Hao Shuai , Tang Fei-fei , Li Bin , Zhou Xian-ming , Liu Li-sheng , Xia Liang-shu
Published: October 2021

The kinetics of U(IV) produced by hydrazine reduction of U(VI) with platinum as a catalyst in nitric acid media was studied to reveal the reaction mechanism and optimize the reaction process. Electron spin resonance (ESR) was used to determine the influence of nitric acid oxidation. The effects of nitric acid, hydrazine, U(VI) concentration, catalyst dosage and temperature on the reaction rate were also studied. In addition, the simulation of the reaction process was performed using density functional theory. The results show that the influence of oxidation on the main reaction is limited when the concentration of nitric acid is below 0.5 mol/L. The reaction kinetics equation below the concentration of 0.5 mol/L is found as: −dc(UO22+)/dt=kc0.5323(UO22+)c0.2074(N2H5+)c−0.2009(H+). When the temperature is 50 ◦C, and the solid/liquid ratio r is 0.0667 g/mL, the reaction kinetics constant is k=0.00199 (mol/L)0.4712/min. Between 20 ◦C and 80 ◦C, the reaction rate gradually increases with the increase of temperature, and changes from chemically controlled to diffusion-controlled. The simulations of density functional theory give further insight into the influence of various factors on the reaction process, with which the reaction mechanisms are determined according to the reaction kinetics and the simulation results.
Vacuum ultraviolet photodissociation dynamics of N2O+hv→N2(X1Σg+)+O(1S) in the short wavelength tail of D1Σ+ band
Authors: Liao Hong , Li Zheng , Yuan Dao-fu , Chen Wen-tao , Wang Xing-an , Yu Sheng-rui , Yang Xue-ming
Published: October 2021

Vacuum ultraviolet photodissociation dynamics of N2O+hv→N2(X1Σg+)+O(1S0) in the short wavelength tail of D1Σ+ band has been investigated using the time-sliced velocity-mapped ion imaging technique by probing the images of the O(1S0) photoproducts at a set of photolysis wavelengths including 121.47 nm, 122.17 nm, 123.25 nm and 123.95 nm. The product total kinetic energy release distributions, vibrational state distributions of the N2(X1Σg+) photofragments and angular anisotropy parameters have been obtained by analyzing the raw O(1S0) images. It is noted that additional vibrationally excited photoproducts (3≤v≤8) with a Boltzmann-like feature start to appear except the non-statistical component as the photolysis wavelength decreases to 123.25 nm, and the corresponding populations become more pronounced with decreasing of the photolysis wave-length. Furthermore, the vibrational state specific anisotropy parameter β at each photolysis wavelength exhibits a drastic fluctuation near β=1.75 at v<8, and decreases to a minimum as the vibrational quantum number further increases. While the overall anisotropy parameter β for the N2(X1Σg+)+O(1S0) channel presents a roughly monotonical increase from 1.63 at 121.47 nm to 1.95 at 123.95 nm. The experimental observations suggest that there is at least one fast nonadiabatic pathway from initially prepared D1Σ+ state to the dissociative state with bent geometry dominating to generate the additional vibrational structures at high photoexcitation energies.
Recent implementations in LASP 3.0: Global neural network potential with multiple elements and better long-range description
Authors: Kang Pei-lin , Shang Cheng , Liu Zhi-pan
Published: October 2021

LASP (large-scale atomistic simulation with neural network potential) software developed by our group since 2018 is a powerful platform (www.lasphub.com) for performing atomic simulation of complex materials. The software integrates the neural network (NN) potential technique with the global potential energy surface exploration method, and thus can be utilized widely for structure prediction and reaction mechanism exploration. Here we introduce our recent update on the LASP program version 3.0, focusing on the new functionalities including the advanced neural network training based on the multi-network framework, the newly-introduced S7 and S8 power type structure descriptor (PTSD). These new functionalities are designed to further improve the accuracy of potentials and accelerate the neural network training for multiple-element systems. Taking Cu-C-H-O neural network potential and a heterogeneous catalytic model as the example, we show that these new functionalities can accelerate the training of multi-element neural network potential by using the existing single-network potential as the input. The obtained double-network potential CuCHO is robust in simulation and the introduction of S7 and S8 PTSDs can reduce the root-mean-square errors of energy by a factor of two.
Genetic evaluation in Merinos: the past and future opportunities
Authors: Atkins K. D.
Published: October 2021

An abbreviated history of genetic evaluation in Merinos demonstrates the remarkable changes that have occurred over the past 50 years. The amount of information available from an increasing number of studs adopting detailed measurement and recording is enormous and much effort has been directed at encouraging selection practices in studs on the basis of this information. In the past we have relied on genetic gains made in the ram breeding sector to be transferred on average to ram buyers, after a lag, for the benefit of the industry. But ram buyers can markedly influence their productivity by being active participants in genetic evaluation rather than relying on gains trickling down on average from ram breeders. Strategies for commercial producers involving choice of ram breeder(s), effective use of breeding values for ram purchases, and on-farm selection and management in the commercial flock are canvassed.
Review of extremity dosimetry in nuclear medicine
Authors: Kollaard Robert , Zorz Alessandra , Dabin Jérémie , Covens Peter , Cooke Jennie , Crabbé Melissa , Cunha Lidia , Dowling Anita , Ginjaume Mercè , McNamara Leanne
Published: October 2021

The exposure of the fingers is one of the major radiation protection concerns in nuclear medicine (NM). The purpose of this paper is to provide an overview of the exposure, dosimetry and protection of the extremities in NM. A wide range of reported finger doses were found in the literature. Historically, the highest finger doses are found at the fingertip in the preparation and dispensing of 18F for diagnostic procedures and 90Y for therapeutic procedures. Doses can be significantly reduced by following recommendations on source shielding, increasing distance and training. Additionally, important trends contributing to a lower dose to the fingers are the use of automated procedures (especially for positron emission tomography (PET)) and the use of prefilled syringes. On the other hand, the workload of PET procedures has substantially increased during the last ten years. In many cases, the accuracy of dose assessment is limited by the location of the dosimeter at the base of the finger and the maximum dose at the fingertip is underestimated (typical dose ratios between 1.4 and 7). It should also be noted that not all dosimeters are sensitive to low-energy beta particles and there is a risk for underestimation of the finger dose when the detector or its filter is too thick. While substantial information has been published on the most common procedures (using 99mTc, 18F and 90Y), less information is available for more recent applications, such as the use of 68Ga for PET imaging. Also, there is a need for continuous awareness with respect to contamination of the fingers, as this factor can contribute substantially to the finger dose.
Lifetime measurement of the 260 g.s. at SAMURAI
Authors: Storck S , Caesar C , Kahlbow J , Panin V , Ahn D S , Atar L , Aumann T , Baba H , Boretzky’ K , Chae H , Chiga N , Choi S , Cortés M L , Cortina-Gil D , Deshayes Q , Doornenbal P , Elekes Z , Fukuda N , Gašparić I , Hahn K I , Halász Z , Hirayama A , Hwang J , Inabe N , Isobe T , Kim S , Kobayashi T , Körper D , Marques M , Matsumoto M , Murakami T , Murray I , Nakamura T , Nilsson T , Otsu H , Paschalis S , Parlog M , Petri M , Rossi D , Saito A , Sasano M , Scheit H , Schrock P , Shimizu Y , Simon H , Sohler D , Sorlin O , Stuhl L , Suzuki H , Syndikus I , Takeda H , Törnqvist H , Togano Y , Tomai T , Uesaka T , Yamada H , Yang Z , Yasuda M , Yoneda K I
Published: October 2021

The ground state of the neutron unbound nucleus 26O is speculated to have a lifetime in the pico-second regime. In order to determine the decay lifetime of the 26 O ground state with high sensitivity and precision, a new method has been applied. The experiment was performed in December 2016 at the Superconducting Analyzer for MUlti-particle from Radio Isotope Beams (SAMURAI) at the Radioactive Isotope Beam Factory (RIBF) at RIKEN. A 27F beam was produced in the fragment separator BigRIPS and impinged on a W/Pt target 26
O
26
O outside the target. Thus, the velocity difference between the decay neutrons and the fragment 1 O delivers a characteristic spectrum from which the lifetime can be extracted.
Possible influence of the warm pool ITCZ on compound climate extremes during the boreal summer
Authors: Basconcillo Joseph , Moon Il-Ju , Wang Bin , Mistry Malcolm
Published: October 2021

In a globally changing climate, there is a growing concern for understanding and predicting compound climate extremes. However, the relationship of compound climate extremes with each other has been mostly analyzed in isolation and/or on regional scales. Little attention has been paid to their simultaneous occurrence and compound impacts worldwide. Here we demonstrate that the compound climate extremes in the Northern Hemisphere during the boreal summer are interconnected from the tropics to the Arctic. This connection originates from the interannual variations of the Indo-Pacific warm pool’s intertropical convergence zone (ITCZ). We demonstrate that the warm pool ITCZ (WPI) convection possibly influences three major teleconnection patterns (i.e. zonal, meridional, and circumglobal) where compound climate extremes occur along the wave train excited by the WPI convection. Most notably, the WPI can sufficiently explain climate variabilities in the North Atlantic region, which influences the occurrence of compound climate extremes in many parts of Europe and North America. Our findings advance the understanding of the interannual global/regional variability of climate extremes and are potentially valuable for predicting seasonal high-impact climate extremes.
On the localization of measure induced Toeplitz operators on the Bergman space
Authors: Zorboska Nina
Published: October 2021

We prove that a Toeplitz operator with a complex Borel measure symbol whose total variation is Carleson is strongly localized, thus improving the recent localization results from Sadeghi and Zorboska [J. Math. Anal. Appl. 485 (2020), p. 16]. We also show that as a corollary, we get yet another view of some of the previously known results on Toeplitz operators with BMO symbols.
Identification of Hemoglobin Variants Prevalent in China and Their Effects on Hemoglobin A1c Measurements
Authors: Xu Anping , Chen Weidong , Xu Miao , Xie Weijie , Ji Ling
Published: October 2021

Objectives

We aimed to evaluate the effects of hemoglobin (Hb) variants prevalent in China on HbA1c measurements and to identify them during HbA1c measurements.

Methods

We evaluated a cation-exchange high-performance liquid chromatography (HPLC) method (Bio-Rad D-100), a capillary electrophoresis (CE) method (Capillarys 3 TERA), an immunoassay (Cobas c501), and a boronate affinity method (Premier Hb9210, as a comparative method) for HbA1c measurements in the presence of Hb variants prevalent in China.

Results

The Bio-Rad D-100 and Capillarys 3 TERA gave specific retention times and numeric migration positions for each Hb variant, respectively, showing excellent interindividual reproducibility. All methods showed statistically significant differences (P < .01) for several variants. Clinically significant effects were observed for the Bio-Rad D-100 (Hb New York and Hb J-Bangkok), Capillarys 3 TERA (Hb New York and Hb J-Bangkok), and Cobas c501 (Hb New York). Among 297 samples with Hb variants, there were 75 (25.3%) unacceptable results for Bio-Rad D-100, 28 (9.4%) for Capillarys 3 TERA, and 19 (6.4%) for Cobas c501 compared with the results from Premier Hb9210.

Conclusions

Some Hb variants prevalent in China affect HbA1c measurements. The HPLC retention time and CE migration position can aid in the presumptive identification of Hb variants.
Controlling the microbial composition during the fermentation of Ishizuchi-kurocha
Authors: Li Zuoqian , Jiang Lei , Wei Lingdong , Ohno Tomoki , Syaputri Yolani , Horie Masanori , Iwahashi Hitoshi
Published: October 2021

Ishizuchi-kurocha is a popular postfermented tea in Japan. It is performed by domestic and natural fermentation relied on microorganisms derived from tea leaves or the environment of the manufacturing. Ishizuchi-kurocha undergoes aerobic fermentation of fungi first, then second fermented by anaerobic fermentation of lactic acid bacteria during natural fermentation processing. Aspergillus niger that produces mycotoxin is included in natural fermentation. This research aimed to build a novel fermentation method of Ishizuchi-kurocha by adding industrial koji fungi products and laboratory-cultivated Lactobacillus plantarum (Lactiplantibacillus plantarum) artificially. Thus, safety and quality of tea products could be controlled simply. We found artificial fermentation of Ishizuchi-kurocha could get high lactic acid production within 8 days. Final products only consisted of genus Aspergillus and genus Lactobacillus, while harmful Aspergillus niger was not found. However, artificial fermentation methods also decreased the content of polyphenols when compared with commercial tea.
ConsAlifold: considering RNA structural alignments improves prediction accuracy of RNA consensus secondary structures
Authors: Tagashira Masaki , Asai Kiyoshi
Published: October 2021

Motivation

By detecting homology among RNAs, the probabilistic consideration of RNA structural alignments has improved the prediction accuracy of significant RNA prediction problems. Predicting an RNA consensus secondary structure from an RNA sequence alignment is a fundamental research objective because in the detection of conserved base-pairings among RNA homologs, predicting an RNA consensus secondary structure is more convenient than predicting an RNA structural alignment.

Results

We developed and implemented ConsAlifold, a dynamic programming-based method that predicts the consensus secondary structure of an RNA sequence alignment. ConsAlifold considers RNA structural alignments. ConsAlifold achieves moderate running time and the best prediction accuracy of RNA consensus secondary structures among available prediction methods.

Availability and implementation

ConsAlifold, data and Python scripts for generating both figures and tables are freely available at https://github.com/heartsh/consalifold.

Supplementary information

Supplementary data are available at Bioinformatics online.
Pathophysiological pathways in patients with heart failure and atrial fibrillation
Authors: Santema Bernadet T , Arita Vicente Artola , Sama Iziah E , Kloosterman Mariëlle , van den Berg Maarten P , Nienhuis Hans L A , Van Gelder Isabelle C , van der Meer Peter , Zannad Faiez , Metra Marco , Ter Maaten Jozine M , Cleland John G , Ng Leong L , Anker Stefan D , Lang Chim C , Samani Nilesh J , Dickstein Kenneth , Filippatos Gerasimos , van Veldhuisen Dirk J , Lam Carolyn S P , Rienstra Michiel , Voors Adriaan A
Published: October 2021

Aims

Atrial fibrillation (AF) and heart failure (HF) are two growing epidemics that frequently co-exist. We aimed to gain insights into the underlying pathophysiological pathways in HF patients with AF by comparing circulating biomarkers using pathway overrepresentation analyses.

Methods and results

From a panel of 92 biomarkers from different pathophysiological domains available in 1620 patients with HF, we first tested which biomarkers were dysregulated in patients with HF and AF (n = 648) compared with patients in sinus rhythm (n = 972). Secondly, pathway overrepresentation analyses were performed to identify biological pathways linked to higher plasma concentrations of biomarkers in patients who had HF and AF. Findings were validated in an independent HF cohort (n = 1219, 38% with AF). Patient with AF and HF were older, less often women, and less often had a history of coronary artery disease compared with those in sinus rhythm. In the index cohort, 24 biomarkers were up-regulated in patients with AF and HF. In the validation cohort, eight biomarkers were up-regulated, which all overlapped with the 24 biomarkers found in the index cohort. The strongest up-regulated biomarkers in patients with AF were spondin-1 (fold change 1.18, P = 1.33 × 10−12), insulin-like growth factor-binding protein-1 (fold change 1.32, P = 1.08 × 10−8), and insulin-like growth factor-binding protein-7 (fold change 1.33, P = 1.35 × 10−18). Pathway overrepresentation analyses revealed that the presence of AF was associated with activation amyloid-beta metabolic processes, amyloid-beta formation, and amyloid precursor protein catabolic processes with a remarkable consistency observed in the validation cohort.

Conclusion

In two independent cohorts of patients with HF, the presence of AF was associated with activation of three pathways related to amyloid-beta. These hypothesis-generating results warrant confirmation in future studies.
Clinical risk factors and P wave indices in prediction of atrial fibrillation development during long-term follow-up after acute ST-segment elevation myocardial infarction
Authors: Baturova M , Demidova M.M , Carlson J , Erlinge D , Platonov P.G
Published: October 2021

Introduction

In patients with high thromboembolic risk detection of atrial fibrillation (AF) is crucial for implementation of proper anticoagulation therapy, which highlights the need for identification of patients at risk for AF. P wave indices reflect atrial structural abnormalities linked to AF development.

Purpose

We aimed to assess the value of clinical risk factors and P wave indices in prediction of incident AF after acute ST-segment elevation myocardial infarction (STEMI) in patients undergoing primary percutaneous intervention (PCI).

Methods

Study sample comprised of 2277 consecutive patients with STEMI admitted to a tertiary care hospital for primary PCI from 2007 to 2010. SWEDEHEART registry was used as the source of information regarding clinical characteristics and events during index admission. Patients without known AF at discharge were included in the current study (n=1837, mean age 65±12 years, 30% females). AF in follow-up (median 9, interquartile range 25–75% (IQR) 7–10 years) was documented by linkage with the Swedish National Patient Register and Swedish Cause-of-Death Register. The closest available ECGs prior to STEMI (median 448, interquartile rate 25–75% 112–1390 days before STEMI) were extracted from the regional electronic ECG databases and automatically processed using Glasgow algorithm. P-wave duration, PR interval, P-wave frontal axis and P terminal force in lead V1 (PTF-V1) were assessed. PTF-V1 >40 mm*ms was considered abnormal.

Results

In follow-up incident AF was documented in 285 patients (15.4%). In univariate Cox regression analysis age, hypertension, history of myocardial infarction, heart failure, history of stroke, smoking status, P wave duration >120 ms, PR interval and abnormal PTF-V1 predicted the AF development during follow-up (Table). In multivariate Cox regression analysis in which significantly associated variables were included only age (hazard ratio (HR) 1.07, 95% CI 1.05–1.08, p<0.001) and abnormal PTF-V1 (HR 1.49, 95% CI 1.08–2.05, p=0.015, Figure) remained independent predictors of incident AF.

Conclusion

In patients with acute STEMI incident AF developed during long-term follow-up after discharge from hospital was strongly associated with age and atrial structural abnormalities reflected as abnormal PTF-V1 on pre-STEMI ECG which might serve as a tool in risk stratification of STEMI patients in regard to AF development.

Funding Acknowledgement

Type of funding sources: Public Institution(s). Main funding source(s): Scholarship grant from Swedish Institute. Table 1Figure 1