bluuebunny/crossref_metadata_2025 huggingface dataset:
Experimental investigation of the sedimentation behavior of metal droplets in liquid–liquid systems
Authors: Qian Lijuan , He Wenwen , Liu Jingqi , Zhu Chenlin , Zhou Fang , Ding Hang , Lin Jianzhong
Published: January 2023

The accurate sedimentation of metal droplets is of great importance in metal droplet-based three-dimensional printing. Detailed investigations of the process of metal droplet collision in a liquid–liquid system are still lacking, relative to studies on the atmospheric environment. In this study, the dynamics of the sedimentation behavior of metal droplets in a liquid–liquid system are experimentally investigated using a high-speed imaging system. The experimental results showed that with an increased impact velocity, metal droplets successively appear after the collision as coalescence, coalescence accompanied by rebound, and rebound. There is a critical impact velocity between the rebound and coalescence, which is related to the surface tension and droplet size of the metal droplets. Analysis of the mechanism of coalescence showed that mechanical oscillations occur during coalescence, which leads to a variation in the inherent surface tension. The greater the impact velocity, the greater the variation. In addition, a semi-empirical prediction formula for the Weber number and maximum spreading factor in the coalescence of metal droplets is developed. This work provides an improved theoretical understanding and superior practical printing efficiency and quality.
Exact non-adiabatic coupling vectors for the time-dependent density functional based tight-binding method
Authors: Niehaus Thomas A.
Published: January 2023

We report on non-adiabatic coupling vectors between electronic excited states for the time-dependent-density functional theory based tight-binding (TD-DFTB) method. The implementation includes orbital relaxation effects that have been previously neglected and covers also the case of range-separated exchange-correlation functionals. Benchmark calculations with respect to first principles TD-DFT highlight the large dependence of non-adiabatic couplings on the functional. Closer investigations of the topology around a conical intersection between excited states show that TD-DFTB delivers near-exact values of the Berry phase, which paves the way for consistent non-adiabatic molecular dynamics simulations for large systems.
Ultrasonic treatment to enhance seed germination and vigour of wheat (Triticum durum) in association with γ-aminobutyric acid (GABA) shunt pathway
Authors: Samarah Nezar H. , AL-Quraan Nisreen A. , Al-Wraikat Batool S.
Published: January 2023

Treatments of wheat (Triticum durum L.) seeds with sonication or hydropriming may enhance seed germination and vigour in association with γ-aminobutyric acid (GABA). Therefore, the objective of this study is to examine the effect of sonication and hydropriming treatments on seed germination of wheat through the characterisation of seed germination performance, GABA shunt metabolite level (GABA, glutamate, and alanine), and the level of glutamate decarboxylase (GAD) mRNA transcription. Wheat seeds were exposed to three treatments for 0, 5, 10, 15, and 20 min: (1) sonication with water; (2) sonication without water; and (3) hydropriming without sonication. Treated seeds were evaluated for germination percentage, mean time to germinate, germination rate index in the warm germination test, and seedling emergence and shoot length in the cold test. GABA shunt metabolites level (GABA, glutamate, and alanine), and the level of GAD mRNA transcription were measured for the seeds after treatments and for seedlings during germination and cold tests. Seeds treated with sonication or hydropriming treatments had a higher germination rate index (faster germination) in the standard germination test, and higher seedling emergence and shoot length in the cold test. Seeds treated with sonication or hydropriming treatments showed an enhancement in GABA shunt and their metabolites (alanine and glutamate), and GAD mRNA transcription level compared to untreated-control seeds. In conclusion, the sonication or hydropriming treatments significantly improved the germination performance of wheat and enhanced GABA metabolism to maintain the C:N metabolic balance, especially under cold stress.
Statistical analysis of residual stresses in austenitic pipe girth welds
Authors: Weltevreden M. , Coules H. , Hadley I. , Janin Y.J.
Published: January 2023

Residual stresses created from welding have a direct influence on fracture mechanisms of cracks and flaws in and around welded regions. Excessive residual stress can lead to unexpected failures and an important property in fitness-for-service calculations. In this work, an experimental database of the residual stress of low heat input austenitic girth welds is analysed for statistical correlation. The combined measurement profiles indicate normality throughout the weld thickness. Two-sample tests of grouped datasets were additionally carried out to examine potential relationships within the data. Presented measurements were characterised by location from weld centre, and similarly, by pipe aspect ratio. Results indicate a moderate influence of dimension ratio on residual stress in piping components suggesting potential for additional consideration in fitness-for-service procedures.
A study on residual stress generation versus recrystallisation in FSW joint of dissimilar alloy pair of the AA5083 and HSLA steel
Authors: Sahu Mrinal , Paul Atanu , Sinha Sudip K. , Ganguly Subhas
Published: January 2023

The distribution of residual stresses across the joint interface of dissimilar joining between AA5083 and HSLA steel by friction stir welding technique was investigated through 2D XRD method and a numerical simulation model. The measured and simulated residual stress distributions are compared and discussed in the context of active recrystallisation mechanism and the possible presence of intermetallic compound (IMC) layers across the joint interface. The active dynamic recrystallisation (DRX) and multiple Fe/Al series IMCs as evident from the EBSD and 2D XRD, respectively critically demonstrated the variation in residual stresses between the experimental and theoretical values. The highest residual stress values of 375 and 281 MPa were recorded for the HSLA steel side and AA5083 side, respectively.
Spectral decomposition of atomic structures in heterogeneous cryo-EM
Authors: Esteve-Yagüe Carlos , Diepeveen Willem , Öktem Ozan , Schönlieb Carola-Bibiane
Published: January 2023

We consider the problem of recovering the three-dimensional atomic structure of a flexible macromolecule from a heterogeneous cryogenic electron microscopy (cryo-EM) dataset. The dataset contains noisy tomographic projections of the electrostatic potential of the macromolecule, taken from different viewing directions, and in the heterogeneous case, each cryo-EM image corresponds to a different conformation of the macromolecule. Under the assumption that the macromolecule can be modelled as a chain, or discrete curve (as it is for instance the case for a protein backbone with a single chain of amino-acids), we introduce a method to estimate the deformation of the atomic model with respect to a given conformation, which is assumed to be known a priori. Our method consists on estimating the torsion and bond angles of the atomic model in each conformation as a linear combination of the eigenfunctions of the Laplace operator in the manifold of conformations. These eigenfunctions can be approximated by means of a well-known technique in manifold learning, based on the construction of a graph Laplacian using the cryo-EM dataset. Finally, we test our approach with synthetic datasets, for which we recover the atomic model of two-dimensional and three-dimensional flexible structures from simulated cryo-EM images.
Structural identification of graphene films and nanoislands on 6H-SiC(0001) by direct height measurement
Authors: Ichou Hamza , Alchaar Mohanad , Baris Bulent , Michon Adrien , Dagher Roy , Dujardin Erik , Martrou David
Published: January 2023

By combining non-contact atomic force microscopy (nc-AFM) and Kelvin probe microscopy (KPFM) in ultra high vacuum environment (UHV), we directly measure the height and work function of graphene monolayer on the Si-face of 6H-SiC(0001) with a precision that allows us to differentiate three different types of graphene structures : zero layer graphene (ZLG), Quasi free-standing monolayer graphene (QFMLG) and bilayer graphene (BLG). The height and work function of ZLG are 2.62 ± 0.22 Å and 4.42 ± 0.05 eV respectively, when they are 4.09 ± 0.11 Å and 4.63 ± 0.05 eV for QFMLG. The work function is 4.83 ± 0.05 eV for the BLG. Unlike any other available technique, the local nc-AFM/KPFM dual probe makes it possible to directly identify the nature of nanometer-sized graphene islands that constitute the early nuclei of graphene monolayer grown on 6H-SiC(0001) by chemical vapor deposition.
Teaching physics in real-life contexts: the Beirut explosion
Authors: Echiburu Mauricio , Hernández Carla , Pino Miguel
Published: January 2023

Teaching physics in real-life contexts continues to be a challenge for teachers at different educational levels. In this article, three context-rich problems are proposed to be implemented in the classroom for higher education, using the explosion that occurred in Beirut as a case study. These problems require the search and analysis of real data, integrating technologies as tools to learn physics. In particular, the analysis of images, videos, maps and audio recordings is suggested. The proposed activities are designed to promote active learning of classical mechanics subjects and the development of collaborative skills. The results of each problem allow a discussion based on scientific evidence in the classroom.
Predictions of electromotive force of magnetic shape memory alloy (MSMA) using constitutive model and generalized regression neural network
Authors: Emu Md Esharuzzaman
Published: January 2023

Ferromagnetic shape memory alloys (MSMAs), such as Ni-Mn-Ga single crystals, can exhibit the shape memory effect due to an applied magnetic field at room temperature. Under a variable magnetic field and a constant bias stress loading, MSMAs have been used for actuation applications. Under variable stress and a constant bias field, MSMAs can be used in power harvesting or sensing devices, e.g. in structural health monitoring applications. This behavior is primarily a result of the approximately tetragonal unit cell whose magnetic easy axis is approximately aligned with the short axis of the unit cell within the Ni-Mn-Ga single crystals. Under an applied field, the magnetic easy axis tends to align with the external field. Similarly, under an applied compressive force, the short side of the unit cell tends to align with the direction of the force. This work introduced a new feature to the existing macro-scale magneto-mechanical model for Ni-Mn-Ga single crystal. This model includes the fact that the magnetic easy axis in the two variants is not exactly perpendicular as observed by D’silva et al (2020 Shape Mem. Superelasticity
6 67–88). This offset helps explain some of the power harvesting capabilities of MSMAs. Model predictions are compared to experimental data collected on a Ni-Mn-Ga single crystal. The experiments include both stress-controlled loading with constant bias magnetic field load (which mimics power harvesting or sensing) and field-controlled loading with constant bias compressive stress (which mimics actuation). Each type of test was performed at several different load levels, and the applied field was measured without the MSMA specimen present so that demagnetization does not affect the experimentally measured field as suggested by Eberle et al (2019 Smart Mater. Struct.
28 025022). Results show decent agreement between model predictions and experimental data. Although the model predicts experimental results decently, it does not capture all the features of the experimental data. In order to capture all the experimental features, finally, a generalized regression neural network (GRNN) was trained using the experimental data (stress, strain, magnetic field, & emf) so that it can make a reasonably better prediction.
Manufacturing thin ionic polymer metal composite for sensing at the microscale
Authors: Motreuil Ragot Paul , Hunt Andres , Sacco Leandro Nicolas , Sarro Pasqualina Maria , Mastrangeli Massimo
Published: January 2023

Ionic polymer metal composites (IPMCs) are a class of materials with a rising appeal in biological micro-electromechanical systems (bio-MEMS) due to their unique properties (low voltage output, bio-compatibility, affinity with ionic medium). While tailoring and improving actuation capabilities of IPMCs is a key motivator in almost all IPMC manufacturing reports, very little efforts have been dedicated to sensing using IPMC thinner than 100 µm. Most reports on IPMC manufacturing and utilization rely on 180 µm-thick Nafion with platinum electrodes, too stiff for bio-MEMS applications. The same fabrication process on thinner membranes does yield in very poor electrodes and performance, and needs to be studied to increase flexibility and sensitivity in the microscale range. This study demonstrates an electroless Pt deposition method for fabricating bio-MEMS-suitable 50 µm-thick IPMC samples. First, we perform a comparative study on the platinum distribution within the Nafion backbone as well as on the surface for the standard electroless deposition recipe for thin (50 µm) and thick (180 µm) Nafion. We report strong differences in platinum distribution for thick and thin IPMC that experienced the same manufacturing process. By varying chemical concentrations from the standard recipe we obtain convenient platinum distribution on thin Nafion, with platinum mainly localized in proximity of surface, as well as electrodes with lower sheet resistance. We could measure the flexural rigidity as

3.43
×

10

−
8

N·m2, 46 times lower than standard 180 µm-thick IPMC. The calculated sensitivity is 0.476 ± 0.02 mV mm−1 and the limit of detection for our sensor is 500 ± 20 µm. This procedure sets a milestone for manufacturing 50 µm-thick IPMC for transducers and sensors in bio-MEMS applications.
Ruderman–Kittel–Kasuya–Yosida (RKKY) interaction in Weyl semimetals with tilted energy dispersion
Authors: Kundu Anirban , Bin Siu Zhuo , Jalil Mansoor B A
Published: January 2023

The Ruderman–Kittel–Kasuya–Yosida (RKKY) interaction is an essential long-range magnetic interaction between magnetic impurities or magnetic layered structures, the magnitude of which oscillates with the distance

R

between them. We investigated the RKKY interaction between two magnetic impurities in both time-reversal and inversion symmetry-broken Weyl semimetals (WSMs) where the energy dispersion is tilted in momentum space and the momentum of the conduction electrons is locked with the pseudo-spin. Two important features are revealed: firstly, at the small tilt limit, the RKKY coupling varies quadratically with the tilt parameter and strikingly, at large separation distances

R

, decays as

1

/

R

compared to the conventional

1

/

R

3

dependence exhibited by WSMs with non-tilted dispersion. The slower decay by two orders (i.e.

1

/

R

as opposed to

1

/

R

3

) of the RKKY coupling is significant for maintaining a long-range RKKY coupling. Secondly, the RKKY coupling exhibits an anisotropy with respect to the angle between the tilt direction (w) and the separation direction R, unlike the case of non-tilted WSMs, which exhibits isotropic RKKY coupling. Consequently, the RKKY coupling in tilted WSMs alternately favors ferromagnetic and anti-ferromagnetic orders and vice-versa with the change of the angle. Our results are derived analytically and verified by numerical calculations based on realistic parameter values.
Deforming polar active matter in a scalar field gradient
Authors: Ibrahimi Muhamet , Merkel Matthias
Published: January 2023

Active matter with local polar or nematic order is subject to the well-known Simha-Ramaswamy instability. It is so far unclear how, despite this instability, biological tissues can undergo robust active anisotropic deformation during animal morphogenesis. Here we ask under which conditions protein concentration gradients (e.g. morphogen gradients), which are known to control large-scale coordination among cells, can stabilize such deformations. To this end, we study a hydrodynamic model of an active polar material. To account for the effect of the protein gradient, the polar field is coupled to the boundary-provided gradient of a scalar field that also advects with material flows. Focusing on the large system size limit, we show in particular: (a) the system can be stable for an effectively extensile coupling between scalar field gradient and active stresses, i.e. gradient-extensile coupling, while it is always unstable for a gradient-contractile coupling. Intriguingly, there are many systems in the biological literature that are gradient-extensile, while we could not find any that are clearly gradient-contractile. (b) Stability is strongly affected by the way polarity magnitude is controlled. Taken together, our findings, if experimentally confirmed, suggest new developmental principles that are directly rooted in active matter physics.
LINNA: Likelihood Inference Neural Network Accelerator
Authors: To Chun-Hao , Rozo Eduardo , Krause Elisabeth , Wu Hao-Yi , Wechsler Risa H. , Salcedo Andrés N.
Published: January 2023

Bayesian posterior inference of modern multi-probe cosmological analyses incurs massive computational costs.
For instance, depending on the combinations of probes, a
single posterior inference for the Dark Energy Survey (DES) data had a wall-clock time that ranged from 1 to 21 days using a state-of-the-art computing cluster with 100 cores. These
computational costs have severe environmental impacts and the long wall-clock time slows scientific productivity. To address these difficulties, we introduce LINNA: the Likelihood Inference Neural Network Accelerator. Relative to the baseline DES analyses, LINNA reduces the computational cost associated with posterior inference by a factor of 8–50.
If applied to the first-year cosmological analysis of Rubin Observatory's Legacy Survey of Space and Time (LSST Y1), we conservatively estimate that LINNA will save more than U.S. $300,000 on energy costs, while simultaneously reducing CO2 emission by 2,400 tons. To accomplish these reductions, LINNA automatically builds training data sets, creates neural network emulators, and produces a Markov chain that samples the posterior. We explicitly verify that LINNA
accurately reproduces the first-year DES (DES Y1) cosmological constraints derived from a variety of different data vectors with our default code settings, without needing to retune the algorithm every time.
Further, we find that LINNA is sufficient for enabling accurate and efficient sampling for LSST Y10 multi-probe analyses. We make LINNA publicly available at  https://github.com/chto/linna, to enable others to perform fast and accurate posterior inference in contemporary cosmological analyses.
Excess of lensing amplitude in the Planck CMB power spectrum
Authors: Mokeddem Rahima , Hipólito-Ricaldi Wiliam S. , Bernui Armando
Published: January 2023

Precise measurements of the Planck cosmic microwave background (CMB) angular power spectrum (APS) at small angles have stimulated
accurate statistical analyses of the lensing amplitude parameter A
L. To confirm if it satisfies the value expected by the flat-ΛCDM concordance model, i.e. A
L = 1,
we investigate the spectrum difference obtained as the difference of the measured Planck CMB APS and the Planck best-fit
ΛCDM APS model. To know if this residual spectrum corresponds to statistical noise or if it has a hidden signature that can be accounted for
with a larger lensing amplitude A
L > 1,
we apply the Ljung-Box statistical test and find, with high statistical significance, that the spectrum difference is not statistical noise.
This spectrum difference is then analysed in detail using simulated APS, based on the Planck ΛCDM best-fit model, where the
lensing amplitude is a free parameter.
We explore different binnations of the multipole order ℓ and look for the best-fit lensing amplitude parameter that accounts
for the spectrum difference in a χ
2 procedure.
We find that there is an excess of signal that is well explained by a ΛCDM APS with a non-null lensing amplitude parameter A
lens, with values in the interval [0.10,0.29] at 68% confidence level.
Furthermore, the lensing parameter in the Planck APS should be 1 + A
lens > 1 at ∼ 3σ of statistical confidence.
Additionally, we perform statistical tests that confirm the robustness of this result.
Important to say that this excess of lensing amplitude, not accounted in the Planck's flat-ΛCDM model, could have an impact
on the theoretical expectation of large-scale structures formation once the scales where it was detected correspond to these matter
clustering processes.
Enhancing gravitational wave anisotropies with peaked scalar sources
Authors: Dimastrogiovanni Ema , Fasiello Matteo , Malhotra Ameek , Tasinato Gianmassimo
Published: January 2023

Gravitational wave (GW) backgrounds of cosmological origin are expected to be nearly
isotropic, with small anisotropies resembling those of the cosmic microwave background. We analyse
the case of a scalar-induced GW background and clarify in the process the relation between two
different approaches to calculating GW anisotropies. We focus on GW scenarios sourced by a
significantly peaked scalar spectrum, which are frequently considered in the context of primordial
black holes production. We show that the resulting GW anisotropies are characterised by a distinct
frequency dependence. We explore the observational consequences concentrating on a GW background
enhanced in the frequency band of space-based GW detectors. We study the detectability of the
signal through both cross-correlations among different space-based GW detectors, and among GW and
CMB experiments.
Optimal quantum control via genetic algorithms for quantum state engineering in driven-resonator mediated networks
Authors: Brown Jonathon , Paternostro Mauro , Ferraro Alessandro
Published: January 2023

We employ a machine learning-enabled approach to quantum state engineering based on evolutionary algorithms. In particular, we focus on superconducting platforms and consider a network of qubits—encoded in the states of artificial atoms with no direct coupling—interacting via a common single-mode driven microwave resonator. The qubit-resonator couplings are assumed to be in the resonant regime and tunable in time. A genetic algorithm is used in order to find the functional time-dependence of the couplings that optimise the fidelity between the evolved state and a variety of targets, including three-qubit GHZ and Dicke states and four-qubit graph states. We observe high quantum fidelities (above 0.96 in the worst case setting of a system of effective dimension 96), fast preparation times, and resilience to noise, despite the algorithm being trained in the ideal noise-free setting. These results show that the genetic algorithms represent an effective approach to control quantum systems of large dimensions.
Multilingual Realities, Monolingual Ideologies: Social Media Representations of Spanish as a Heritage Language in the United States
Authors: Kircher Ruth , Kutlu Ethan
Published: January 2023

Little is known about how monolingual ideologies and their effects manifest in online contexts as compared to offline contexts. We conducted a corpus-assisted discourse study to investigate this, with a focus on Twitter representations of Spanish as a heritage language in the USA. We analysed two corpora (one English and one Spanish—over 30 million words), examining frequencies, collocations, concordance lines, and larger text segments. The results revealed evidence of the same ideologies found in offline contexts: normative monolingualism (drawing on the one-nation-one-language ideology and language purity ideologies) as well as raciolinguistic ideologies. We show how the semiotic processes of iconization and erasure lead to the (evidently erroneous) essentialization of Spanish heritage language speakers as a homogeneous group of un-American, racialized immigrants with broken language. This discursive creation of difference constitutes the basis for the systematic discrimination of Spanish heritage language speakers, thus reflecting and reproducing social inequality. Our findings therefore indicate the necessity of extending planning measures to protect heritage language speakers (and other minority groups) from offline contexts to online contexts.
Trends in surgical techniques for the treatment of esophageal and gastroesophageal junction cancer: the 2022 update
Authors: de Groot E M , Goense L , Kingma B F , Haverkamp L , Ruurda J P , van Hillegersberg R
Published: January 2023

The aim of this study was to evaluate the current practice in surgical techniques for esophageal and gastroesophageal junction cancer surgery worldwide and to compare the results to the previous surveys in 2007 and 2014. An online survey was sent out among surgical members of the International Society for Diseases of the Esophagus, the World Organization for Specialized Studies on Disease of the Esophagus, the International Gastric Cancer Association, the Association of Upper Gastrointestinal Surgery of Great Britain and Ireland and Dutch gastroesophageal surgeons via the network of the investigators. In total, 260 surgeons completed the survey representing 52 countries and 6 continents; Europe 56%, Oceania 14%, Asia 14%, South-America 9%, North-America 7%. Of the responding surgeons, 39% worked in a hospital that performed >51 esophagectomies per year. Total minimally invasive esophagectomy was the preferred technique (53%) followed by hybrid esophagectomy (26%) of which 7% consisted of a minimally invasive thoracic phase and 19% of a minimally invasive abdominal phase. Total open esophagectomy was preferred by 21% of the respondents. Total minimally invasive esophagectomy was significantly more often performed in high-volume centers compared with non-high-volume centers (P = 0.002). Robotic assistance was used in 13% during the thoracic phase and 6% during the abdominal phase. Minimally invasive transthoracic esophagectomy has become the preferred approach for esophagectomy. Although 21% of the surgeons prefer an open approach, 26% of the surgeons perform a hybrid procedure which may reflect further transition towards the use of total minimally invasive esophagectomy.
International multicenter survey on screening and confirmatory testing in primary aldosteronism
Authors: Naruse Mitsuhide , Murakami Masanori , Katabami Takuyuki , Kocjan Tomaz , Parasiliti-Caprino Mirko , Quinkler Marcus , St-Jean Matthieu , O'Toole Sam , Ceccato Filippo , Kraljevic Ivana , Kastelan Darko , Tsuiki Mika , Deinum Jaap , Torre Edelmiro Menéndez , Puar Troy , Markou Athina , Piaditis George , Laycock Kate , Wada Norio , Grytaas Marianne Aardal , Kobayashi Hiroki , Tanabe Akiyo , Tong Chin Voon , Gallego Nuria Valdés , Gruber Sven , Beuschlein Felix , Kürzinger Lydia , Sukor Norlela , Azizan Elena A B Aisha , Ragnarsson Oskar , Nijhoff Michiel F , Maiolino Giuseppe , Dalmazi Guido Di , Kalugina Valentina , Lacroix André , Furnica Raluca Maria , Suzuki Tomoko
Published: January 2023

Objective

Primary aldosteronism (PA) is one of the most frequent causes of secondary hypertension. Although clinical practice guidelines recommend a diagnostic process, details of the steps remain incompletely standardized.

Design

In the present SCOT-PA survey, we have investigated the diversity of approaches utilized for each diagnostic step in different expert centers through a survey using Google questionnaires. A total of 33 centers from 3 continents participated.

Results

We demonstrated a prominent diversity in the conditions of blood sampling, assay methods for aldosterone and renin, and the methods and diagnostic cutoff for screening and confirmatory tests. The most standard measures were modification of antihypertensive medication and sitting posture for blood sampling, measurement of plasma aldosterone concentration (PAC) and active renin concentration by chemiluminescence enzyme immunoassay, a combination of aldosterone-to-renin ratio with PAC as an index for screening, and saline infusion test in a seated position for confirmatory testing. The cutoff values for screening and confirmatory testing showed significant variation among centers.

Conclusions

Diversity of the diagnostic steps may lead to an inconsistent diagnosis of PA among centers and limit comparison of evidence for PA between different centers. We expect the impact of this diversity to be most prominent in patients with mild PA. The survey raises 2 issues: the need for standardization of the diagnostic process and revisiting the concept of mild PA. Further standardization of the diagnostic process/criteria will improve the quality of evidence and management of patients with PA.
Filling the gap in distribution ranges and conservation status in Ctenomys (Rodentia: Ctenomyidae)
Authors: Caraballo Diego A , López Sabrina Laura , Botero-Cañola Sebastián , Gardner Scott Lyell
Published: January 2023

South American subterranean rodents of the genus Ctenomys (Rodentia, Ctenomyidae, tuco-tuco) are one of the most diverse genera among mammals. Recently described species, new taxonomic revisions, and new distribution range delimitation made the revision of distribution areas and conservation status of these mammals mandatory. Implementing the first part of the DAMA protocol (document, assess, monitor, act), here we compile updated sets of species distribution range maps and use these and the number of collection localities to assess the conservation status of ctenomyids. We integrate potential for conservation in protected areas, and levels of habitat transformation to revise previous conservation status assessments and propose the first assessment for all Data Deficient or not evaluated species of tuco-tucos. Our results indicate that 53 (78%) of these species are threatened and that 47 (69%) have little or no overlap with protected areas, emphasizing the urgent need to conduct conservation efforts. Here, 18 of 22 species previously classified as Data Deficient resulted in them being put in an at-risk category (VU, EN, CR). In addition, nine species that have not been previously evaluated were classified as threatened, with these two groups comprising more than 47% of the known species. These results posit that the Ctenomyidae are the rodent family with the greatest number of species at risk of extinction. Finally, a total of 33 (49%) species have been reported from three or fewer localities; all considered threatened through the approach implemented in this study. These geographically restricted taxa should be given more attention in conservation programs since the richness of this genus relies on the survival of such species.
Caveolin‐2 in association with nuclear lamina controls adipocyte hypertrophy
Authors: Choi Moonjeong , Kwon Hayeong , Pak Yunbae
Published: January 2023

Here, we identify that Caveolin‐2 (Cav‐2), an integral membrane protein, controls adipocyte hypertrophy in association with nuclear lamina. In the hypertrophy stage of adipogenesis, pY19‐Cav‐2 association with lamin A/C facilitated the disengagement of CCAAT/enhancer‐binding protein α (C/EBPα) and peroxisome proliferator‐activated receptor γ (PPARγ) from lamin A/C and repressed Cav‐2 promoter at the nuclear periphery for epigenetic activation of Cav‐2, and thereby promoted C/EBPα and PPARγ‐induced adipocyte hypertrophy. Stable expression of Cav‐2 was required and retained by phosphorylation, deubiquitination, and association with lamin A/C for the adipocyte hypertrophy. However, obese adipocytes exhibited augmented Cav‐2 stability resulting from the up‐regulation of lamin A/C over lamin B1, protein tyrosine phosphatase 1B (PTP1B), and nuclear deubiquitinating enzyme (DUB), Uchl5. Our findings show a novel epigenetic regulatory mechanism of adipocyte hypertrophy by Cav‐2 at the nuclear periphery.
The Consequences of Step 2 Clinical Skills Examination Discontinuation for Medical Schools and Sustainability Plans for Clinical Skills Assessment
Authors: Phillips Abigail , Hauer Karen E. , Chen H. Carrie , Wray Alisa , Watanaskul Sarah , Boscardin Christy K.
Published: January 2023

Purpose

Comprehensive clinical skills examinations using standardized patients are widely used to assess multiple physician competencies. However, these exams are resource intensive. With the discontinuation of the Step 2 Clinical Skills (CS) exam in 2021, how medical schools will change their approaches to comprehensive clinical skills exams is unknown. This study explores school responses to this change and future directions of comprehensive clinical skills exams using the program sustainability framework.

Method

This cross-sectional, descriptive study surveyed medical school curriculum deans at 150 Liaison Committee on Medical Education–accredited U.S. medical schools from September to October 2021. The 30-question survey included questions about medical school and participant role, current comprehensive clinical skills exams, sustainability dimensions, and challenges and future directions. Descriptive statistics were used to characterize responses, and content analysis was used to identify themes in the open-ended responses.

Results

Educators at 75 of 150 institutions (50%) responded. Sixty-three respondents (84%) reported conducting a comprehensive clinical skills exam. The comprehensive clinical skills exam assessed readiness for graduation (51 [81%]), provided feedback for students (49 [78%]), evaluated curricula (38 [60%]), provided information for medical student performance evaluation or communication with residency (10 [16%]), and assessed other factors (6 [10%]), including preparation for Step 2 CS in the past and readiness for advancement to fourth year of medical school (multiple responses were allowed). Factors facilitating sustainability included sufficient funding to continue the exam (55 [87%]) and the belief that clinical skills assessment in medical school is now more important after discontinuation of the Step 2 CS exam (55 [87%]). Challenges to sustainability included organizational capacity and limited interinstitutional collaboration.

Conclusions

Educators remain committed to the purpose of comprehensive clinical skills exams. Adapting to changed licensing requirements while sustaining clinical skills exams enables innovation and improvement in assessment of clinical competence.
Combined Surgical Strategies Adjusted to Clinical Evaluations for Severe Upper Eyelid Cicatricial Entropion and Trichiasis
Authors: Zhang Li , Hou Zhijia , Li Yang , Li Dongmei
Published: January 2023

Background:

The management of cicatricial entropion and trichiasis represents a therapeutic challenge. The authors determined the long-term stability of combined surgical procedures in severe cases.

Methods:

The authors retrospectively studied consecutive patients with severe upper eyelid cicatricial entropion and trichiasis treated between 2019 and 2021 at Beijing Tongren Eye Center. Combined surgical procedures adjusted to clinical evaluations were performed. Clinical characteristics, procedures, and surgical outcomes were retrieved.

Results:

The authors included data on 58 eyelids (25 left and 33 right) from 39 patients (19 males and 20 females). The mean age was 54.81 years. Follow-up averaged 20.67 months. Common diagnoses were chemical injury, trachoma, and chronic conjunctivitis. Seven eyelids with eyelid margin entropion were successfully treated using anterior lamellar recession and gray line split. Seven eyelids with eyelid margin entropion and posterior lamellar deficits were effectively treated using anterior lamellar recession, gray line split, and posterior lamellar lengthening. Thirty-eight eyelids with recalcitrant eyelid margin entropion were treated using anterior lamellar recession and gray line split with graft, with a success rate of 94.74% and 89.47%, 3 and 6 months after the operation, respectively. Six eyelids with recalcitrant eyelid margin entropion and posterior lamellar deficits were effectively treated using anterior lamellar recession, gray line split with graft, and posterior lamellar lengthening. Among various grafts, pediculated orbicularis muscle was significantly different from banked sclera or resected tarsus (P = 0.011, P < 0.001).

Conclusions:

In severe upper eyelid cicatricial entropion and trichiasis, combined surgical procedures showed good functional and cosmetic results with excellent long-term stability.
Non-operable glioblastoma: proposition of patient-specific forecasting by image-informed poromechanical model
Authors: Urcun Stéphane , Baroli Davide , Rohan Pierre-Yves , Skalli Wafa , Lubrano Vincent , Bordas Stéphane P.A. , Sciumè Giuseppe
Published: January 2023

We propose a novel image-informed glioblastoma mathematical model within a reactive multiphase poromechanical framework. Poromechanics offers to model in a coupled manner the interplay between tissue deformation and pressure-driven fluid flows, these phenomena existing simultaneously in cancer disease. The model also relies on two mechano-biological hypotheses responsible for the heterogeneity of the GBM: hypoxia signaling cascade and interaction between extra-cellular matrix and tumor cells. The model belongs to the category of patient-specific image-informed models as it is initialized, calibrated and evaluated by the means of patient imaging data. The model is calibrated with patient data after 6 cycles of concomitant radiotherapy chemotherapy and shows good agreement with treatment response 3 months after chemotherapy maintenance. Sensitivity of the solution to parameters and to boundary conditions is provided. As this work is only a first step of the inclusion of poromechanical framework in image-informed glioblastoma mathematical models, leads of improvement are provided in the conclusion.
Aging-associated augmentation of gut microbiome virulence capability drives sepsis severity
Authors: Colbert James F. , Kirsch Joshua M. , Erzen Christopher L. , Langouët-Astrié Christophe J. , Thompson Grace E. , McMurtry Sarah A. , Kofonow Jennifer M. , Robertson Charles E. , Kovacs Elizabeth J. , Sullivan Ryan C. , Hippensteel Joseph A. , Sawant Namrata V. , De Nisco Nicole J. , McCollister Bruce D. , Schwartz Robert S. , Horswill Alexander R. , Frank Daniel N. , Duerkop Breck A. , Schmidt Eric P.
Published: January 2023

Prior research has focused on host factors as mediators of exaggerated sepsis-associated morbidity and mortality in older adults. This focus on the host, however, has failed to identify therapies that improve sepsis outcomes in the elderly. We hypothesized that the increased susceptibility of the aging population to sepsis is not only a function of the host, but also reflects longevity-associated changes in the virulence of gut pathobionts. We utilized two complementary models of gut microbiota-induced experimental sepsis to establish the aged gut microbiome as a key pathophysiologic driver of heightened disease severity. Further murine and human investigations into these polymicrobial bacterial communities demonstrated that age was associated with only subtle shifts in ecological composition, but an overabundance of genomic virulence factors that have functional consequence on host immune evasion.

One Sentence Summary

The severity of sepsis in the aged host is in part mediated by longevity-associated increases in gut microbial virulence.
In end-stage kidney disease, inflammation, erythron abnormalities and declined kidney function tests are accompanied by increased affective symptoms, chronic-fatigue, and fibromyalgia
Authors: Al-Hakeim Hussein Kadhem , Twaij Basim Abd Al-Raheem , Ahmed Mustafa Hassan , Almulla Abbas F. , Moustafa Shatha Rouf , Maes Michael
Published: January 2023

Background

Numerous neuropsychiatric symptoms, including affective symptoms, chronic fatigue syndrome, and fibromyalgia symptoms, are present in patients with end-stage renal disease (ESRD). This study examines the relationship between neuropsychiatric symptoms and red blood cell (RBC) parameters, kidney function tests, zinc, C-reactive protein, and calcium levels in patients with ESRD.

Methods

The above biomarkers and the Beck-Depression Inventory, the Hamilton Anxiety Rating Scale, and the Fibro-Fatigue Rating Scale were measured in 70 patients with end-stage renal disease (ESRD) and 46 healthy controls.

Results

Increased scores of depressive, anxious, cognitive, and physiosomatic symptoms (including chronic fatigue, fibromyalgia, and autonomous symptoms) characterise ESRD. One latent vector could be extracted from these diverse symptom domains, which are, therefore, manifestations of a common core referred to as the physio-affective phenome. The combined effects of aberrations in red blood cells (RBC) (number of RBC, hematocrit, and haemoglobin), kidney function tests (glomerular filtration rate, ureum, creatinine, albumin, and total serum protein), C-reactive protein, zinc, and copper explained 85.0% of the variance in the physio-affective phenome. In addition, the effects of kidney function decline on the phenome were partially mediated by RBC aberrations and elevated copper, whereas the effects of dialysis frequency were entirely mediated by decreased zinc and elevated CRP.

Conclusions

Affective (depression and anxiety), cognitive, and physiosomatic symptoms due to ESRD are interrelated manifestations of the physio-affective phenome, which is driven by (in descending order of importance) kidney dysfunctions, erythron deficits, inflammation, elevated copper, and decreased zinc.
Engraftment of wild-type alveolar type II epithelial cells in surfactant protein C deficient mice
Authors: Iezza Daniela , Predella Camilla , Ni Keyue , Murray John W. , Liu Hsiao-Yun , Saqi Anjali , Glasser Stephan W. , Dorrello N. Valerio
Published: January 2023

Childhood interstitial lung disease (chILD) secondary to pulmonary surfactant deficiency is a devastating chronic lung disease in children. Clinical presentation includes mild to severe respiratory failure and fibrosis. There is no specific treatment, except lung transplantation, which is hampered by a severe shortage of donor organs, especially for young patients. Repair of lungs with chILD represents a longstanding therapeutic challenge but cellular therapy is a promising strategy. As surfactant is produced by alveolar type II epithelial (ATII) cells, engraftment with normal or gene-corrected ATII cells might provide an avenue to cure. Here we used a chILD disease-like model,Sftpc−/−mice, to provide proof-of-principle for this approach.Sftpc−/−mice developed chronic interstitial lung disease with age and were hypersensitive to bleomycin. We could engraft wild-type ATII cells after low dose bleomycin conditioning. Transplanted ATII cells produced mature SPC and attenuated bleomycin-induced lung injury up to four months post-transplant. This study demonstrates that partial replacement of mutant ATII cells can promote lung repair in a mouse model of chILD.
Oncogenic Ras deregulates cell-substrate interactions during mitotic rounding and respreading to alter cell division orientation
Authors: Ganguli Sushila , Wyatt Tom , Meyer Tim , Baum Buzz , Matthews Helen K.
Published: January 2023

Oncogenic Ras has been shown to change the way cancer cells divide by increasing the forces generated during mitotic rounding. In this way, RasV12enables cancer cells to divide across a wider range of mechanical environments than normal cells. Here, we identify a further role for oncogenic Ras-ERK signalling in division by showing that RasV12expression alters the shape, division orientation and respreading dynamics of cells as they exit mitosis, in a manner that depends on MEK and ERK. Many of these effects appear to result from the impact of RasV12signalling on actomyosin contractility, since RasV12induces the severing of retraction fibres that normally guide spindle positioning and provide a memory of the interphase cell shape. In support of this idea, the RasV12phenotype is reversed by inhibition of actomyosin contractility, and can be mimicked by the loss of cell-substrate adhesion during mitosis. Thus, the induction of oncogenic Ras-ERK signalling leads to rapid changes in division orientation that, along with the effects of RasV12on cell growth and cell cycle progression, are likely to disrupt epithelial tissue organisation and contribute to cancer dissemination.
A systematic review of the factors that contribute towards mental health in the fire service
Authors: Garmon-Jones Lydia , Hanna Paul , John Mary
Published: January 2023

Purpose

Concerns have been raised regarding the mental health of firefighters. In response to this, existing literature reviews have highlighted the significant role of trauma in influencing mental health and the experience of post-traumatic stress within firefighters.

Design/methodology/approach

This paper builds on the existing reviews and makes an original contribution to knowledge by systematically reviewing research exploring additional factors that contribute to poor mental health in firefighters.

Findings

This review finds that factors such as sleep, occupational stress, length of service, coping style and social support all influence negative mental health within firefighters. However, this paper also suggests there are challenges to distinguishing the nature of these relationships, due to the possible bidirectional nature of the relationships and study limitations.

Originality/value

Finally, we conclude by suggesting a clear need for further research to explore the biological, psychological and social factors influencing mental health outcomes in firefighters and the direction of these relationships, in order to inform effective intervention and support.