bluuebunny/crossref_metadata_2025 huggingface dataset:
Formin Activity and mDia1 Contribute to Maintain Axon Initial Segment Composition and Structure
Authors: Zhang Wei , Ciorraga María , Mendez Pablo , Retana Diana , Boumedine-Guignon Norah , Achón Beatriz , Russier Michaël , Debanne Dominique , Garrido Juan José
Published: August 2021

The axon initial segment (AIS) is essential for maintaining neuronal polarity, modulating protein transport into the axon, and action potential generation. These functions are supported by a distinctive actin and microtubule cytoskeleton that controls axonal trafficking and maintains a high density of voltage-gated ion channels linked by scaffold proteins to the AIS cytoskeleton. However, our knowledge of the mechanisms and proteins involved in AIS cytoskeleton regulation to maintain or modulate AIS structure is limited. In this context, formins play a significant role in the modulation of actin and microtubules. We show that pharmacological inhibition of formins modifies AIS actin and microtubule characteristics in cultured hippocampal neurons, reducing F-actin density and decreasing microtubule acetylation. Moreover, formin inhibition diminishes sodium channels, ankyrinG and βIV-spectrin AIS density, and AIS length, in cultured neurons and brain slices, accompanied by decreased neuronal excitability. We show that genetic downregulation of the mDia1 formin by interference RNAs also decreases AIS protein density and shortens AIS length. The ankyrinG decrease and AIS shortening observed in pharmacologically inhibited neurons and neuron-expressing mDia1 shRNAs were impaired by HDAC6 downregulation or EB1-GFP expression, known to increase microtubule acetylation or stability. However, actin stabilization only partially prevented AIS shortening without affecting AIS protein density loss. These results suggest that mDia1 maintain AIS composition and length contributing to the stability of AIS microtubules.
Individual differences in need satisfaction and intentions to vote for specific political parties – results from Germany
Authors: Sindermann Cornelia , Montag Christian
Published: August 2021

Understanding the psychological basis of individuals' voting intentions is of tremendous importance because voting for specific parties and politicians can influence political developments. In the present study associations of individuals’ satisfaction of each of Maslow’s five basic need categories with voting intentions were investigated in a German sample and these results were compared to results on associations between personality and voting intentions. An online survey was completed by N = 2593 (n = 1035 men) individuals. Participants provided information on socio-demographic characteristics, filled in the Need Satisfaction Inventory, the Big Five Inventory, and stated which of the major German parties they would vote for if general elections were held the following Sunday. Data were analyzed using the statistical software R and RStudio. Among others, it was found that higher satisfaction of physiological needs and higher satisfaction of safety and security needs were associated with intentions to vote for the currently governing party alliance, the CDU/CSU, versus for the right-wing AfD. Regarding personality, among others Openness was positively associated with intentions to vote for nearly every party (except the CDU/CSU) versus for the AfD. Effect sizes of associations were overall rather small; generally speaking, those related to the Need Satisfaction Inventory were even slightly smaller than those found for personality traits. The present results indicate that other factors aside from needs and personality must be considered to understand voting. Therefore, this study sets a starting point for further investigations to replicate and expand the present findings.
Psychometric properties of the Cognitive Fusion Questionnaire in females with fibromyalgia
Authors: Luque-Reca Octavio , Gillanders David , Catala Patricia , Peñacoba Cecilia
Published: August 2021

Cognitive fusion, or the degree to which a person is entangled with their thoughts and takes them literally, is considered a normal yet detrimental cognitive process associated with diverse negative outcomes across healthy and disordered functioning, including in fibromyalgia. Given the relevance of this cognitive process, the aim of the present study is to generate empirical evidence on the reliability and validity of the Cognitive Fusion Questionnaire (CFQ) in a sample of Spanish females with fibromyalgia. In this cross-sectional study, 230 Spanish females diagnosed with fibromyalgia (mean age 56.89 years; SD = 8.96) were assessed on cognitive fusion, pain catastrophizing, personality traits, positive and negative affect, anxiety symptoms, depressive symptoms and disease severity. Confirmatory factor analysis, reliability and validity analyses were performed. The CFQ showed a unidimensional structure, adequate temporal stability and good internal consistency. In addition, convergent and discriminant validity were found with respect to dispositional, pain-related, affective, mood and anxious measures; as well as incremental and criterion validity in the prediction of psychological symptoms or the disease severity status. The CFQ has been revealed as a solid and valid measure in the evaluation of cognitive fusion in Spanish females suffering from fibromyalgia, and may also be useful in clinical contexts due to the relationships it has shown with important outcomes. Limitations and future directions are also discussed.
Influences of Shot Peening Parameters on Mechanical Properties and Fatigue Behavior of 316 L Steel: Experimental, Taguchi Method and Response Surface Methodology
Authors: Maleki Erfan , Unal Okan , Reza Kashyzadeh Kazem
Published: August 2021

Severe plastic deformation methods like shot peening (SP) are known as efficient surface treatments and grain refining processes which afford more effective properties in metallic materials. In the current research, a comprehensive study was carried out on SP of AISI 316 L steel. It included 42 different SP treatments with a wide range of Almen intensities of 12–27 A and various coverage degrees (100%–1500%). Several experimental tests were conducted in order to explore the microstructure, grain size, surface topography, hardness, wettability, and residual stresses of the specimens. Next, two different approaches including Taguchi method (TM), and response surface methodology (RSM) were deployed for modeling, analysis, and optimization. RSM and TM were used to examine the influence of the effective parameters. Based on the optimized results, the fatigue behavior of the selected treatments was investigated experimentally in both smooth and notched specimens.

Graphical abstract
The Contribution of Evolutionary Game Theory to Understanding and Treating Cancer
Authors: Wölfl Benjamin , te Rietmole Hedy , Salvioli Monica , Kaznatcheev Artem , Thuijsman Frank , Brown Joel S. , Burgering Boudewijn , Staňková Kateřina
Published: August 2021

Evolutionary game theory mathematically conceptualizes and analyzes biological interactions where one’s fitness not only depends on one’s own traits, but also on the traits of others. Typically, the individuals are not overtly rational and do not select, but rather inherit their traits. Cancer can be framed as such an evolutionary game, as it is composed of cells of heterogeneous types undergoing frequency-dependent selection. In this article, we first summarize existing works where evolutionary game theory has been employed in modeling cancer and improving its treatment. Some of these game-theoretic models suggest how one could anticipate and steer cancer’s eco-evolutionary dynamics into states more desirable for the patient via evolutionary therapies. Such therapies offer great promise for increasing patient survival and decreasing drug toxicity, as demonstrated by some recent studies and clinical trials. We discuss clinical relevance of the existing game-theoretic models of cancer and its treatment, and opportunities for future applications. Moreover, we discuss the developments in cancer biology that are needed to better utilize the full potential of game-theoretic models. Ultimately, we demonstrate that viewing tumors with evolutionary game theory has medically useful implications that can inform and create a lockstep between empirical findings and mathematical modeling. We suggest that cancer progression is an evolutionary competition between different cell types and therefore needs to be viewed as an evolutionary game.
A phospho-proteomic study of cetuximab resistance in KRAS/NRAS/BRAFV600 wild-type colorectal cancer
Authors: Georgiou Alexandros , Stewart Adam , Vlachogiannis Georgios , Pickard Lisa , Valeri Nicola , Cunningham David , Whittaker Steven R. , Banerji Udai
Published: August 2021

Purpose

We hypothesised that plasticity in signal transduction may be a mechanism of drug resistance and tested this hypothesis in the setting of cetuximab resistance in patients with KRAS/NRAS/BRAFV600 wild-type colorectal cancer (CRC).

Methods

A multiplex antibody-based platform was used to study simultaneous changes in signal transduction of 55 phospho-proteins in 12 KRAS/NRAS/BRAFV600 wild-type CRC cell lines (6 cetuximab sensitive versus 6 cetuximab resistant) following 1 and 4 h in vitro cetuximab exposure. We validated our results in CRC patient samples (n = 4) using ex vivo exposure to cetuximab in KRAS/NRAS/BRAFV600 cells that were immunomagnetically separated from the serous effusions of patients with known cetuximab resistance.

Results

Differences in levels of phospho-proteins in cetuximab sensitive and resistant cell lines included reductions in phospho-RPS6 and phospho-PRAS40 in cetuximab sensitive, but not cetuximab resistant cell lines at 1 and 4 h, respectively. In addition, phospho-AKT levels were found to be elevated in 3/4 patient samples following ex vivo incubation with cetuximab for 1 h. We further explored these findings by studying the effects of combinations of cetuximab and two PI3K pathway inhibitors in 3 cetuximab resistant cell lines. The addition of PI3K pathway inhibitors to cetuximab led to a significantly higher reduction in colony formation capacity compared to cetuximab alone.

Conclusion

Our findings suggest activation of the PI3K pathway as a mechanism of cetuximab resistance in KRAS/NRAS/BRAFV600 wild-type CRC.
Global well-posedness and long-time behavior of the fractional NLS
Authors: Sy Mouhamadou , Yu Xueying
Published: August 2021

In this paper, our discussion mainly focuses on equations with energy supercritical nonlinearities. We establish probabilistic global well-posedness (GWP) results for the cubic Schrödinger equation with any fractional power of the Laplacian in all dimensions. We consider both low and high regularities in the radial setting, in dimension$$\ge 2$$≥2. In the high regularity result, anInviscid - Infinite dimensional (IID) limitis employed while in the low regularity global well-posedness result, we make use of the Skorokhod representation theorem. The IID limit is presented in details as an independent approach that applies to a wide range of Hamiltonian PDEs. Moreover we discuss the adaptation to the periodic settings, in any dimension, for smooth regularities.
Necessary Conditions for Interpolation by Multivariate Polynomials
Authors: Antezana Jorge , Marzo Jordi , Ortega-Cerdà Joaquim
Published: August 2021

Let$$\Omega $$Ωbe a smooth, bounded, convex domain in$${\mathbb {R}}^n$$Rnand let$$\Lambda _k$$Λkbe a finite subset of$$\Omega $$Ω. We find necessary geometric conditions for$$\Lambda _k$$Λkto be interpolating for the space of multivariate polynomials of degree at mostk. Our results are asymptotic ink. The density conditions obtained match precisely the necessary geometric conditions that sampling sets are known to satisfy and are expressed in terms of the equilibrium potential of the convex set. Moreover we prove that in the particular case of the unit ball, forklarge enough, there are no bases of orthogonal reproducing kernels in the space of polynomials of degree at mostk.
Evaluation of Ball End Micromilling for Ti6Al4V ELI Microneedles Using a Nanoadditive Under MQL Condition
Authors: Celis Pavel , Vazquez Elisa , Soria-Hernández Cintya G. , Bargnani Diego , Rodriguez Ciro A. , Ceretti Elisabetta , García-López Erika
Published: August 2021

The use of nanoadditives in lubricants has gained much attention to the research community due to the enhancement of tribological properties and cooling capabilities. This paper studies the advantages of using a MQL (Minimum Quantity of Lubrication) system and nanoadditive in the manufacture of microneedle arrays in Ti6Al4V ELI alloy. Tungsten carbide ball nose tools with a cutting diameter of 200 µm were used in experimental tests. Surface and dimensional characterization was performed to evaluate the impact of a nanoadditive to a vegetable-based oil. Additionally, cutting forces and cutting edge radius (CER) were measured while needles were machined. Experimental tests confirmed that micro end milling with nanoadditives provide slightly better dimensional features and low cutting forces compared to oil. The performance of nanoadditives resulted in a reduction of surface roughness (~ 0.3 μm). Qualitative study of microneedles illustrated burr formation on needle surface manufactured without a nanoadditive solution. Results reveal an increment of CER using low feed rate values (2.0 µm/flute) while a reduction of CER was observed with feed rates up to 2.5 µm/flute. Our results indicated that the addition of nanoadditives to vegetable oil promotes a better product surface topography and cutting tool performance.
Code-based encryption techniques with distributed cluster head and energy consumption routing protocol
Authors: Jalasri M. , Lakshmanan L.
Published: August 2021

Fog computing and the Internet of Things (IoT) played a crucial role in storing data in the third-party server. Fog computing provides various resources to collect data by managing data security. However, intermediate attacks and data sharing create enormous security challenges like data privacy, confidentiality, authentication, and integrity issues. Various researchers introduce several cryptographic techniques; security is still significant while sharing data in the distributed environment. Therefore, in this paper, Code-Based Encryption with the Energy Consumption Routing Protocol (CBE-ECR) has been proposed for managing data security and data transmission protocols using keyed-hash message authentication. Initially, the data have been analyzed, and the distributed cluster head is selected, and the stochastically distributed energy clustering protocol is utilized for making the data transmission. Code-driven cryptography relies on the severity of code theory issues such as disorder demodulation and vibration required to learn equivalence. These crypto-systems are based on error codes to build a single-way function. The encryption technique minimizes intermediate attacks, and the data have protected all means of transmission. In addition to data security management, the introduced CBE-ECR reduces unauthorized access and manages the network lifetime successfully, leading to the effective data management of 96.17% and less energy consumption of 21.11% than other popular methods.The effectiveness of the system is compared to the traditional clustering techniques.
Vesikoureteraler Reflux beim Kind – eine Übersicht
Authors: Frech-Doerfler Martina , Holland-Cunz Stefan , Sommer Vivienne
Published: August 2021

Der vesikoureterale Reflux (VUR) beschreibt einen nichtphysiologischen Reflux der Harnblase in die Nieren. Während beim primären Reflux und jüngeren Kindern eine hohe Spontanheilungsrate besteht, ist diese beim sekundären Reflux deutlich geringer. Der VUR ist häufig mit einer „bladder bowel dysfunction“ assoziiert, die primär behandelt werden sollte. Hauptkomplikation ist die Refluxnephropathie mit Bildung von Nierennarben und nachfolgend möglicher Einschränkung der Nierenfunktion. Die Therapiemöglichkeiten reichen, abhängig von der klinischen Präsentation und den bestehenden Risikofaktoren, von abwartendem Verhalten bis zur offenen Chirurgie. Ein leichtgradiger VUR (Grad I–II) muss heute nicht mehr behandelt werden. Bei hochgradigem VUR und wiederholten Durchbruchsinfektionen ist die Indikation zur subureteralen Unterspritzung oder zur Ureterneuimplantation gegeben.
The effects of ejector adiabatic absorber on heat and mass transfer of binary nanofluid with heat transfer additives
Authors: Muhammad Umar Aliyu , Bhattacharyya Debabratta , Endrino Jose Louis , Fereres Sonia
Published: August 2021

This paper presents experimental results on the study of the effects of ejector adiabatic absorber on heat and mass transfer of binary nanofluid with heat transfer additives (2-ethyl-1-hexanol and gum Arabic). In this case, H2O/lithium bromide-alumina nanofluid was suggested due to a growing interest in absorption heat transfer working fluid for solar energy application. An experimental setup — ejector test rig — was designed to study the absorption, heat, and mass transfer rate as a result of refrigerant vapour mass flow entrained by the ejector adiabatic absorber. The study was carried out at different solution mass flowrate (0.051 to 0.17 kg/s) with three prepared sample solutions, which include pure LiBr solution, LiBr-Alumina nanofluid without heat transfer additives, and LiBr-Alumina nanofluid with heat transfer additives. The absorption rate, mass transfer coefficient, heat transfer rate, and heat transfer coefficient for the three samples were reported. On the other hand, the percentage enhancements for all the parameters — at a suitable flow rate of 0.085 kg/s — due to the addition of alumina without and with heat transfer additives were recorded. The absorption rate enhancements were 25% and 96%, the enhancement rates of mass transfer coefficient recorded were 20% and 82%, the heat transfer rate enhancements were 85% and 183%, and the heat transfer coefficient enhancements obtained were 72% and 156% with addition of alumina nanoparticles only and alumina nanoparticles with heat transfer additives respectively. Material mass balance analysis suggests that mass inflow in the ejector equals to the mass outflow from the ejector, indicating a complete absorption of the entrained refrigerant vapour beyond which falling film absorption can occur due to concentration. This article also presents experimental evidence of the capability of ejector as strong adiabatic absorber, heat, and mass transfer component, which were earlier reported using numerical models.
From equal access to employment to equal career opportunities?
Authors: Mithout Anne-Lise
Published: August 2021

In Japan, disability policies have significantly evolved over the last twenty years, be it in the field of social welfare, education or employment. Until recently, most workers with disabilities were employed in blue-collar jobs involving repetitive tasks. However, the reform of the education system that took place in 2006 has contributed to the development of mainstream schooling and improved the accessibility of universities for disabled students. Therefore, the number of students with disabilities in higher education is slowly increasing, as well as the number of people with disabilities holding a university degree, thus challenging the common representation of people with disabilities as unskilled workers. Yet, the academic literature on disabled people’s employment has hardly investigated the specificities of the situation of qualified disabled workers. The case of people with disabilities holding a university degree or a professional qualification, is mainly discussed in terms of access, through the lens of the transition from university to employment. But what are the career patterns of qualified disabled workers on the long run? This paper aims to explore to what extent disability impact qualified disabled workers’ career development. It analyzes interview data collected during two fieldwork stays in Japan and discusses qualified disabled workers’ lived experiences of employment with a long-term perspective.
Unsteady shock wave dynamics in accelerating and decelerating flight
Authors: Mahomed I. , Roohani H. , Skews B.W. , Gledhill I.M.A.
Published: August 2021

Increasingly agile manoeuvre is an advantage in the flight of aircraft, missiles and aerial vehicles, but the principles of accelerating aerodynamics in the transonic regime are only now being fully investigated. This study contributes to the understanding of shock and separation effects on drag during axial acceleration, using a simple geometric configuration. Unsteady shock wave behavior was numerically investigated for an axisymmetric cone-cylinder using a commercial solver and the Moving Reference Frame acceleration technique. This acceleration technique was validated using unsteady numerical and experimental methods. The cone-cylinder was accelerated from Mach number 0.6 to Mach number 1.2 at 100g constant and deceleration was from Mach number 1.2 until Mach number 0.6 at –100g constant. Three cone angles were tested for the cone-cylinder with uniform cylinder diameter. Acceleration through the transonic Mach regime was characterised by a delayed and gradual shock wave development when compared to steady state, demonstrating a clear flow history effect. Deceleration through the transonic Mach regime was characterised by shock wave propagation from the base to the nose. New flow structures appeared during deceleration that do not have counterparts in the steady state, including shock interactions and propagating expansion-compression features. Gross changes in the unsteady drag coefficient curves for each cone-angle are explained with reference to unsteady shock wave behaviour for accelerating and decelerating motion.
Lowermost Mantle Shear‐Velocity Structure From Hierarchical Trans‐Dimensional Bayesian Tomography
Authors: Mousavi Sima , Tkalčić Hrvoje , Hawkins Rhys , Sambridge Malcolm
Published: August 2021

The core‐mantle boundary (CMB) is the most extreme boundary within the Earth where the liquid, iron‐rich outer core interacts with the rocky, silicate mantle. The nature of the lowermost mantle atop the CMB, and its role in mantle dynamics, is not completely understood. Various regional studies have documented significant heterogeneities at different spatial scales. While there is a consensus on the long scale length structure of the inferred S‐wave speed tomograms, there are also notable differences stemming from different imaging methods and datasets. Here we aim to overcome over‐smoothing and avoid over‐fitting data for the case where the spatial coverage is sparse and the inverse problem ill‐posed. We present an S‐wave tomography model at a global scale for the Lowermost Mantle (LM) using the Hierarchical Trans‐Dimensional Bayesian Inversion (HTDBI) framework, LM‐HTDBI. Our LM‐HTDBI analysis of ScS‐S travel times includes uncertainty, and the complexity of the model is deduced from the data itself through an implicit parameterization of the model space. Our comprehensive resolution estimates indicate that short‐scale anomalies are significant and resolvable features of the lowermost mantle regardless of the chosen mantle‐model reference to correct the travel times above the D’’ layer. The recovered morphology of the Large‐Low‐Shear‐wave Velocity Provinces (LLSVPs) is complex, featuring small high‐velocity patches among low‐velocity domains. Instead of two large, unified, and smooth LLSVPs, the newly obtained images suggest that their margins are not uniformly flat.
Controls on Riverine Dissolved Organic Matter Composition Across an Arctic‐Boreal Latitudinal Gradient
Authors: Johnston Sarah Ellen , Carey Joanna C. , Kellerman Anne , Podgorski David C. , Gewirtzman Jonathan , Spencer Robert G. M.
Published: August 2021

Climatic changes are transforming northern high‐latitude watersheds as permafrost thaws and vegetation and hydrology shift. These changes have implications for the source and reactivity of riverine dissolved organic matter (DOM), and thus biogeochemical cycling, across northern high‐latitude systems. In this study, we use a latitudinal gradient from the interior to the North Slope of Alaska to evaluate seasonal and landscape drivers of DOM composition in this changing Arctic environment. To assess DOM source and composition, we used absorbance and fluorescence spectroscopy to measure DOM optical properties, lignin biomarker analyses to evaluate vascular plant contribution to the DOM pool, and Fourier transform ion cyclotron resonance mass spectrometry (FT‐ICR MS) to assess DOM compositional changes. We found that seasonal inputs of DOM at elevated discharge during the freshet were typically more aromatic in nature with higher lignin concentrations and carbon‐normalized yields. Landscape characteristics were a major control on dissolved organic carbon (DOC) yields and DOM composition. More northern watersheds, which were steeper, underlain by continuous permafrost, and exhibited a mix of barren and lichen/moss vegetation cover, exported less DOC with relatively more aliphatic DOM compared to more southern basins. Watersheds with deeper active layers exported DOM that was more aromatic with higher polyphenolic and condensed aromatic relative abundances and lignin yields, likely sourced from shallow subsurface flow during high discharge periods. However, contributions from deeper groundwater to streamflow is expected to increase, which would increase interactions of groundwater with mineral soils and decrease aromatic DOM contributions during periods of low discharge.
Remarkable Metabolic Reconfiguration due to N Deficiency and an Ammonium‐to‐Nitrate Shift in the Free‐Living Effrenium voratum (Symbiodiniaceae)
Authors: Li Tangcheng , Yu Liying , Chen Xibei , Lin Xin , Li Ling , Guo Chentao , Lin Senjie
Published: August 2021

Nitrogen (N) controls the growth of phytoplankton and the phytosymbionts of corals, but little is known about N nutrition in free‐living planktonic species of the Symbiodiniaceae family. Here, with physiological and transcriptomic analyses, we investigated how Effrenium voratum responded to N deficiency or a nitrate (NO3−) to ammonium (NH4+) switch. The results from batch cultures showed that E. voratum grew well on both NH4+ and NO3−, but NH4+ supported higher yield. Furthermore, when provided with both NH4+ and NO3−, E. voratum preferentially utilized NH4+ and consumed it faster than NO3−. Inhibitory effects of NH4+ on cell growth and photochemical efficiency were detected at ≥ 440 μM in a dose‐dependent manner. When NH4+ and NO3− were compared, only 582 genes were differentially expressed; NH4+ promoted expression of genes related to N transport, carbon fixation, chlorophyll synthesis, and cell division. In contrast, N deficiency inhibited cell division, decreased Chl a content, and changed expression of a large number (4,553) of genes involved in a wide range of metabolic processes from N acquisition, carbon fixation, photosynthate translocation, glycolysis, ROS production, to the cell cycle. This study provides baseline information about N nutrition in a free‐living symbiodiniacean dinoflagellate, which will be useful for comparative research with symbiotic counterparts. The findings also underscore the need to consider differences among phytoplankton groups in responding to forms (NH4+ versus NO3−) and availability (N repletion versus deficiency) of N‐nutrient in modeling N effects on phytoplankton dynamics.
Increasing Coral Reef Resilience Through Successive Marine Heatwaves
Authors: Fox Michael D. , Cohen Anne L. , Rotjan Randi D. , Mangubhai Sangeeta , Sandin Stuart A. , Smith Jennifer E. , Thorrold Simon R. , Dissly Laura , Mollica Nathan R. , Obura David
Published: August 2021

Ocean warming is causing declines of coral reefs globally, raising critical questions about the potential for corals to adapt. In the central equatorial Pacific, reefs persisting through recurrent El Niño heatwaves hold important clues. Using an 18‐year record of coral cover spanning three major bleaching events, we show that the impact of thermal stress on coral mortality within the Phoenix Islands Protected Area (PIPA) has lessened over time. Disproportionate survival of extreme thermal stress during the 2009–2010 and 2015–2016 heatwaves, relative to that in 2002–2003, suggests that selective mortality through successive heatwaves may help shape coral community responses to future warming. Identifying and facilitating the conditions under which coral survival and recovery can keep pace with rates of warming are essential first steps toward successful stewardship of coral reefs under 21st century climate change.
Predicting the Gulf of Mexico Hurricane Season With 500‐hPa Temperature
Authors: Miller P. W. , Trepanier J. C.
Published: August 2021

While North Atlantic tropical cyclone (TC) forecasts are numerous, the number of Gulf of Mexico (GOM) storms is normally left ambiguous. Motivated by the 2020 GOM hurricane season, this study introduces two methods of anticipating upcoming GOM TC frequency on June 1 of each year: (a) statistically transforming Climate Forecast System (CFS)‐predicted June–November GOM 500‐hPa temperature (T500); and (b) applying a 0.284 multiplier, the climatological proportion of GOM versus North Atlantic TCs, to a representative, widely circulated North Atlantic‐wide forecast. Both methods perform skillfully, especially given their simplicity. Though warm T500 normally inhibits deep convection and is not generally considered among statistical TC forecasts, it is comparatively well represented by modeling systems. Additionally, T500 is well correlated with traditional, yet less accurately resolved, TC environmental parameters. While unfavorable to individual TCs, T500 generally (though indirectly) indicates several difficult‐to‐model physical aspects of more favorable GOM TC environments.
Topographic Asymmetry Across the Arctic
Authors: Zwieback Simon
Published: August 2021

Aspect‐dependent differences in steepness provide insight into the fate and formation of permafrost‐affected landscapes, but the circum‐Arctic distribution of topographic asymmetry remains unknown. The maps derived here add nuance to the notion that periglacial conditions promote steeper north‐facing slopes. Only 20% of the area exhibits elevated north–south asymmetry, chiefly in rugged terrain. Across all moderate‐relief landscapes, there is a bell‐shaped trend with temperature. Steeper south‐facing slopes are common in very cold and cool regions. In between, steeper north‐facing slopes predominate. Despite multiple caveats, the bell‐shaped trend with temperature suggests controls that vary with climatic factors, including permafrost conditions. The bell‐shaped trend and observations of permafrost degradation further indicate that certain asymmetric transition‐zone landscapes are predisposed to enhanced geomorphic activity in a warming climate.
New Findings of the Sporadic E (Es) Layer Development Around the Magnetic Equator During a High‐Speed Solar (HSS) Wind Stream Event
Authors: Resende L. C. A. , Zhu Y. , Denardini C. M. , Batista I. S. , Shi J. , Moro J. , Chen S. S. , Conceição‐Santos F. , Da Silva L. A. , Andrioli V. F. , Muella M. T. A. H. , Fagundes P. R. , Carrasco A. J. , Pillat V. G. , Wang C. , Liu Z.
Published: August 2021

The equatorial (Esq) and blanketing (Esb) sporadic (Es) layers occur due to the Equatorial Electrojet Current (EEJ) plasma instabilities and tidal wind components, respectively. Both Esq and Esb layers can appear concurrently over some Brazilian equatorial regions due to the peculiar geomagnetic field configuration in this sector. Previous works indicate that the inclination angle limit for the Esq occurrence in ionograms is 7°. However, we found evidence that regions more distant can also experience such equatorial dynamics during disturbed periods. In this context, we deeply investigated this EEJ influence expansion effect by analyzing the Esq layers in regions not so close to the magnetic equator during a high‐speed solar wind stream event that occurred on May 05 and 06, 2018. To explain these atypical Esq layer occurrences, we considered the Es layer parameters obtained from digital ionosondes over the Brazilian regions, São Luís (dip: 9.5°), and Araguatins (dip: 10.5°). We use magnetometer data and a model named MIRE (E Region Ionospheric Model) to validate this mechanism. The results show that the eastward electric field of the Gradient Drift instability in the EEJ is effective during the magnetic storm main phase in the boundary equatorial magnetic sites, creating the Esq layers. Thus, the EEJ plasma irregularity superimposes the wind shear mechanism, changing the Es layer dynamics during disturbed periods over the magnetic equator boundary sites. Therefore, this work establishes new findings of the EEJ influence expansion dynamics in the Es layer formation over the Brazilian regions, which was considered in MIRE for the first time.
Regionally Variable Responses of Nitrogen Fixation to Iron and Phosphorus Enrichment in the Pacific Ocean
Authors: Tanita Iwao , Shiozaki Takuhei , Kodama Taketoshi , Hashihama Fuminori , Sato Mitsuhide , Takahashi Kazutaka , Furuya Ken
Published: August 2021

Iron and phosphorus are major nutrients limiting marine nitrogen fixation. We directly assessed iron and phosphate enrichment using the surface water of the western and central North Pacific subtropical gyre (NPSG), central equatorial Pacific, and eastern South Pacific subtropical gyre (SPSG). Diazotrophic phylotypes showed regionally distinct distribution patterns. The abundances of nifH in UCYN‐A, Trichodesmium, Crocosphaera, and γ‐24774A11 and filaments of Richelia were significantly higher in the central and western NPSG than in the eastern SPSG. The surface dissolved iron concentration was <0.2 nmol l−1 in most of the regions; however, nitrogen fixation was enhanced by the addition of iron only in the western NPSG and equatorial upwelling. In the western NPSG, where surface phosphate was almost exhausted, and levels varied below 7 nmol l−1, diazotrophs also exhibited either phosphate limitation or colimitation by iron and phosphate. The present study demonstrated the limitation of nitrogen fixation by iron and phosphorus individually and colimitation by iron and phosphorus in the western NPSG for the first time, and the data showed that the nutrients limiting nitrogen fixation in the Pacific Ocean differed among the regions, indicating that the response of nitrogen fixation to environmental changes is not uniform.
VAV2 is required for DNA repair and implicated in cancer radiotherapy resistance
Authors: Liu Weiling , Miao Chuanwang , Zhang Shaosen , Liu Yachen , Niu Xiangjie , Xi Yiyi , Guo Wenjia , Chu Jiahui , Lin Ai , Liu Hongjin , Yang Xinyu , Chen Xinjie , Zhong Ce , Ma Yuling , Wang Yuqian , Zhu Shihao , Liu Shuning , Tan Wen , Lin Dongxin , Wu Chen
Published: August 2021

Radiotherapy remains the mainstay for treatment of various types of human cancer; however, the clinical efficacy is often limited by radioresistance, in which the underlying mechanism is largely unknown. Here, using esophageal squamous cell carcinoma (ESCC) as a model, we demonstrate that guanine nucleotide exchange factor 2 (VAV2), which is overexpressed in most human cancers, plays an important role in primary and secondary radioresistance. We have discovered for the first time that VAV2 is required for the Ku70/Ku80 complex formation and participates in non-homologous end joining repair of DNA damages caused by ionizing radiation. We show that VAV2 overexpression substantially upregulates signal transducer and activator of transcription 1 (STAT1) and the STAT1 inhibitor Fludarabine can significantly promote the sensitivity of radioresistant patient-derived ESCC xenografts in vivo in mice to radiotherapy. These results shed new light on the mechanism of cancer radioresistance, which may be important for improving clinical radiotherapy.
Alteration of NMDA receptor trafficking as a cellular hallmark of psychosis
Authors: Espana Agnès , Seth Henrik , Jézéquel Julie , Huang Tingting , Bouchet Delphine , Lepleux Marylin , Gréa Hélène , Bechter Karl , Schneider Marion , Hanse Eric , Groc Laurent
Published: August 2021

A dysfunction of the glutamatergic transmission, especially of the NMDA receptor (NMDAR), constitutes one of the main biological substrate of psychotic disorders, such as schizophrenia. The NMDAR signaling hypofunction, through genetic and/or environmental insults, would cause a neurodevelopmental myriad of molecular, cellular, and network alterations that persist throughout life. Yet, the mechanisms underpinning NMDAR dysfunctions remain elusive. Here, we compared the membrane trafficking of NMDAR in three gold-standard models of schizophrenia, i.e., patient’s cerebrospinal fluids, genetic manipulations of susceptibility genes, and prenatal developmental alterations. Using a combination of single nanoparticle tracking, electrophysiological, biochemical, and behavioral approaches in rodents, we identified that the NMDAR trafficking in hippocampal neurons was consistently altered in all these different models. Artificial manipulations of the NMDAR surface dynamics with competing ligands or antibody-induced receptor cross-link in the developing rat brain were sufficient to regulate the adult acoustic startle reflex and compensate for an early pathological challenge. Collectively, we show that the NMDAR trafficking is markedly altered in all clinically relevant models of psychosis, opening new avenues of therapeutical strategies.
Circulating mature dendritic cells homing to the thymus promote thymic epithelial cells involution via the Jagged1/Notch3 axis
Authors: Wu Haojie , Li Xiaohan , Zhou Chen , Yu Qihong , Ge Shiyao , Pan Zihui , Zhao Yangjing , Xia Sheng , Zhou Xiaoming , Liu Xia , Wang Hui , Shao Qixiang
Published: August 2021

Multiple proinflammatory conditions, including chemotherapy, radiotherapy, transplant rejection, and microbial infections, have been identified to induce involution of the thymus. However, the underlying cellular and molecular mechanisms of these inflammatory conditions inducing apoptosis of thymic epithelial cells (TECs), the main components of the thymus, remain largely unknown. In the circulation, mature dendritic cells (mDCs), the predominant initiator of innate and adaptive immune response, can migrate into the thymus. Herein, we demonstrated that mDCs were able to directly inhibit TECs proliferation and induce their apoptosis by activating the Jagged1/Notch3 signaling pathway. Intrathymic injection of either mDCs or recombinant mouse Jagged1-human Fc fusion protein (rmJagged1-hFc) into mice resulted in acute atrophy of the thymus. Furthermore, DAPT, a γ-secretase inhibitor, reversed the effects induced by mDC or rmJagged1-hFc. These findings suggest that acute or aging-related thymus degeneration can be induced either by mass migration of circulating mDCs in a short period of time or by a few but constantly homing mDCs.
Adropin correlates with aging-related neuropathology in humans and improves cognitive function in aging mice
Authors: Banerjee Subhashis , Ghoshal Sarbani , Girardet Clemence , DeMars Kelly M. , Yang Changjun , Niehoff Michael L. , Nguyen Andrew D. , Jayanth Prerana , Hoelscher Brittany A. , Xu Fenglian , Banks William A. , Hansen Kim M. , Zhang Jinsong , Candelario-Jalil Eduardo , Farr Susan A. , Butler Andrew A.
Published: August 2021

The neural functions of adropin, a secreted peptide highly expressed in the brain, have not been investigated. In humans, adropin is highly expressed in astrocytes and peaks during critical postnatal periods of brain development. Gene enrichment analysis of transcripts correlating with adropin expression suggests processes relevant to aging-related neurodegenerative diseases that vary with age and dementia state, possibly indicating survivor bias. In people aged <40 y and ‘old-old’ (>75 y) diagnosed with dementia, adropin correlates positively with genes involved in mitochondrial processes. In the ‘old-old’ without dementia adropin expression correlates positively with morphogenesis and synapse function. Potent neurotrophic responses in primary cultured neurons are consistent with adropin supporting the development and function of neural networks. Adropin expression in the ‘old-old’ also correlates positively with protein markers of tau-related neuropathologies and inflammation, particularly in those without dementia. How variation in brain adropin expression affects neurological aging was investigated using old (18-month) C57BL/6J mice. In mice adropin is expressed in neurons, oligodendrocyte progenitor cells, oligodendrocytes, and microglia and shows correlative relationships with groups of genes involved in neurodegeneration and cellular metabolism. Increasing adropin expression using transgenesis improved spatial learning and memory, novel object recognition, resilience to exposure to new environments, and reduced mRNA markers of inflammation in old mice. Treatment with synthetic adropin peptide also reversed age-related declines in cognitive functions and affected expression of genes involved in morphogenesis and cellular metabolism. Collectively, these results establish a link between adropin expression and neural energy metabolism and indicate a potential therapy against neurological aging.
Spatio-seasonal variation of water quality influenced by land use and land cover in Lake Muhazi
Authors: Umwali Edovia Dufatanye , Kurban Alishir , Isabwe Alain , Mind’je Richard , Azadi Hossein , Guo Zengkun , Udahogora Madeleine , Nyirarwasa Anathalie , Umuhoza Jeanine , Nzabarinda Vincent , Gasirabo Aboubakar , Sabirhazi Gulnur
Published: August 2021

Understanding the influence of land use/land cover (LULC) on water quality is pertinent to sustainable water management. This study aimed at assessing the spatio-seasonal variation of water quality in relation to land use types in Lake Muhazi, Rwanda. The National Sanitation Foundation Water Quality Index (NSF-WQI) was used to evaluate the anthropogenically-induced water quality changes. In addition to Principal Components Analysis (PCA), a Cluster Analysis (CA) was applied on 12-clustered sampling sites and the obtained NSF-WQI. Lastly, the Partial Least Squares Path Modelling (PLS-PM) was used to estimate the nexus between LULC, water quality parameters, and the obtained NSF-WQI. The results revealed a poor water quality status at the Mugorore and Butimba sites in the rainy season, then at Mugorore and Bwimiyange sites in the dry season. Furthermore, PCA displayed a sample dispersion based on seasonality while NSF-WQI’s CA hierarchy grouped the samples corresponding to LULC types. Finally, the PLS-PM returned a strong positive correlation (+ 0.831) between LULCs and water quality parameters in the rainy season but a negative correlation coefficient (− 0.542) in the dry season, with great influences of cropland on the water quality parameters. Overall, this study concludes that the lake is seasonally influenced by anthropogenic activities, suggesting sustainable land-use management decisions, such as the establishment and safeguarding protection belts in the lake vicinity.
Cardiac mechanics and incident ischemic stroke: the Cardiovascular Health Study
Authors: Kamel Hooman , Bartz Traci M. , Longstreth W. T. , Elkind Mitchell S. V. , Gottdiener John , Kizer Jorge R. , Gardin Julius M. , Kim Jiwon , Shah Sanjiv
Published: August 2021

Recent evidence indicates that our understanding of the relationship between cardiac function and ischemic stroke remains incomplete. The Cardiovascular Health Study enrolled community-dwelling adults ≥ 65 years old. We included participants with speckle-tracking data from digitized baseline study echocardiograms. Exposures were left atrial reservoir strain (primary), left ventricular longitudinal strain, left ventricular early diastolic strain rate, septal e’ velocity, and lateral e’ velocity. The primary outcome was incident ischemic stroke. Cox proportional hazards models were adjusted for demographics, image quality, and risk factors including left ventricular ejection fraction and incident atrial fibrillation. Among 4,000 participants in our analysis, lower (worse) left atrial reservoir strain was associated with incident ischemic stroke (HR per SD absolute decrease, 1.14; 95% CI 1.04–25). All secondary exposure variables were significantly associated with the outcome. Left atrial reservoir strain was associated with cardioembolic stroke (HR per SD absolute decrease, 1.42; 95% CI 1.21–1.67) and cardioembolic stroke related to incident atrial fibrillation (HR per SD absolute decrease, 1.60; 1.32–1.95). Myocardial dysfunction that can ultimately lead to stroke may be identifiable at an early stage. This highlights opportunities to identify cerebrovascular risk earlier and improve stroke prevention via therapies for early myocardial dysfunction.
Use of transcriptomic profiling to identify candidate genes involved in Polyporus umbellatus sclerotial formation affected by oxalic acid
Authors: Xing Yong-Mei , Li Bing , Zeng Xu , Zhou Li-Si , Lee Tae-Soo , Lee Min-Woong , Chen Xiao-Mei , Guo Shun-Xing
Published: August 2021

Polyporus umbellatus is a precious medicinal fungus. Oxalic acid was observed to affect sclerotial formation and sclerotia possessed more medicinal compounds than mycelia. In this study, the transcriptome of P. umbellatus was analysed after the fungus was exposed to various concentrations of oxalic acid. The differentially expressed genes (DEGs) encoding a series of oxidases were upregulated, and reductases were downregulated, in the low-oxalic-acid (Low OA) group compared to the control (No OA) group, while the opposite phenomenon was observed in the high-oxalic-acid (High OA) group. The detection of reactive oxygen species (ROS) in P. umbellatus mycelia was performed visually, and Ca2+ and H2O2 fluxes were measured using non-invasive micro-test technology (NMT). The sclerotial biomass in the Low OA group increased by 66%, however, no sclerotia formed in the High OA group. The ROS fluorescence intensity increased significantly in the Low OA group but decreased considerably in the High OA group. Ca2+ and H2O2 influx significantly increased in the Low OA group, while H2O2 exhibited efflux in the High OA group. A higher level of oxidative stress formed in the Low OA group. Different concentrations of oxalic acid were determined to affect P. umbellatus sclerotial formation in different ways.
Molecular-dynamics-simulation-guided membrane engineering allows the increase of membrane fatty acid chain length in Saccharomyces cerevisiae
Authors: Maertens Jeroen M. , Scrima Simone , Lambrughi Matteo , Genheden Samuel , Trivellin Cecilia , Eriksson Leif A. , Papaleo Elena , Olsson Lisbeth , Bettiga Maurizio
Published: August 2021

The use of lignocellulosic-based fermentation media will be a necessary part of the transition to a circular bio-economy. These media contain many inhibitors to microbial growth, including acetic acid. Under industrially relevant conditions, acetic acid enters the cell predominantly through passive diffusion across the plasma membrane. The lipid composition of the membrane determines the rate of uptake of acetic acid, and thicker, more rigid membranes impede passive diffusion. We hypothesized that the elongation of glycerophospholipid fatty acids would lead to thicker and more rigid membranes, reducing the influx of acetic acid. Molecular dynamics simulations were used to predict the changes in membrane properties. Heterologous expression of Arabidopsis thaliana genes fatty acid elongase 1 (FAE1) and glycerol-3-phosphate acyltransferase 5 (GPAT5) increased the average fatty acid chain length. However, this did not lead to a reduction in the net uptake rate of acetic acid. Despite successful strain engineering, the net uptake rate of acetic acid did not decrease. We suggest that changes in the relative abundance of certain membrane lipid headgroups could mitigate the effect of longer fatty acid chains, resulting in a higher net uptake rate of acetic acid.