bluuebunny/crossref_metadata_2025 huggingface dataset:
Calibration of the near-surface seismic structure in the SCEC community velocity model version 4
Authors: Hu Zhifeng , Olsen Kim B , Day Steven M
Published: May 2022

The near-surface seismic structure (to a depth of about 1000 m), particularly the shear wave velocity (VS), can strongly affect the propagation of seismic waves and, therefore, must be accurately calibrated for ground motion simulations and seismic hazard assessment. The VS of the top (<300 m) crust is often well characterized from borehole studies, geotechnical measurements, and water and oil wells, while the velocities of the material deeper than about 1000 m are typically determined by tomography studies. However, in depth ranges lacking information on shallow lithological stratification, typically rock sites outside the sedimentary basins, the material parameters between these two regions are typically poorly characterized due to resolution limits of seismic tomography. When the alluded geological constraints are not available, models, such as the Southern California Earthquake Center (SCEC) Community Velocity Models (CVMs), default to regional tomographic estimates that do not resolve the uppermost VS values, and therefore deliver unrealistically high shallow VS estimates. The SCEC Unified Community Velocity Model (UCVM) software includes a method to incorporate the near-surface earth structure by applying a generic overlay based on measurements of time-averaged VS in top 30 m (VS30) to taper the upper part of the model to merge with tomography at a depth of 350 m, which can be applied to any of the velocity models accessible through UCVM. However, our 3-D simulations of the 2014 Mw 5.1 La Habra earthquake in the Los Angeles area using the CVM-S4.26.M01 model significantly underpredict low-frequency (<1 Hz) ground motions at sites where the material properties in the top 350 m are significantly modified by the generic overlay (‘taper’). On the other hand, extending the VS30-based taper of the shallow velocities down to a depth of about 1000 m improves the fit between our synthetics and seismic data at those sites, without compromising the fit at well-constrained sites. We explore various tapering depths, demonstrating increasing amplification as the tapering depth increases, and the model with 1000 m tapering depth yields overall favourable results. Effects of varying anelastic attenuation are small compared to effects of velocity tapering and do not significantly bias the estimated tapering depth. Although a uniform tapering depth is adopted in the models, we observe some spatial variabilities that may further improve our method.
Using convolutional neural networks to develop starting models for near-surface 2-D full waveform inversion
Authors: Vantassel Joseph P , Kumar Krishna , Cox Brady R
Published: May 2022

Non-invasive subsurface imaging using full waveform inversion (FWI) has the potential to fundamentally change near-surface (<30 m) site characterization by enabling the recovery of high-resolution (metre-scale) 2-D/3-D maps of subsurface elastic material properties. Yet, FWI results are quite sensitive to their starting model due to their dependence on local-search optimization techniques and inversion non-uniqueness. Starting model dependence is particularly problematic for near-surface FWI due to the complexity of the recorded seismic wavefield (e.g. dominant surface waves intermixed with body waves) and the potential for significant spatial variability over short distances. In response, convolutional neural networks (CNNs) are investigated as a potential tool for developing starting models for near-surface 2-D elastic FWI. Specifically, 100 000 subsurface models were generated to be representative of a classic near-surface geophysics problem; namely, imaging a two-layer, undulating, soil-over-bedrock interface. A CNN has been developed from these synthetic models that is capable of transforming an experimental wavefield acquired using a seismic source located at the centre of a linear array of 24 closely spaced surface sensors directly into a robust starting model for FWI. The CNN approach was able to produce 2-D starting models with seismic image misfits that were significantly less than the misfits from other common starting model approaches, and in many cases even less than the misfits obtained by FWI with inferior starting models. The ability of the CNN to generalize outside its two-layered training set was assessed using a more complex, three-layered, soil-over-bedrock formation. While the predictive ability of the CNN was slightly reduced for this more complex case, it was still able to achieve seismic image and waveform misfits that were comparable to other commonly used starting models, despite not being trained on any three-layered models. As such, CNNs show great potential as tools for rapidly developing robust, site-specific starting models for near-surface elastic FWI.
An anisotropic equation of state for high-pressure, high-temperature applications
Authors: Myhill R
Published: May 2022

This paper presents a strategy for extending scalar (P–V–T) equations of state to self-consistently model anisotropic materials over a wide range of pressures and temperatures under nearly hydrostatic conditions. The method involves defining a conventional scalar equation of state (V(P, T) or P(V, T)) and a fourth-rank tensor state variable $\boldsymbol {\Psi }(V,T)$ whose derivatives can be used to determine the anisotropic properties of materials of arbitrary symmetry. This paper proposes two functional forms for $\boldsymbol {\Psi }(V,T)$ and provides expressions describing the relationship between $\boldsymbol {\Psi }$ and physical properties including the deformation gradient tensor, the lattice parameters, the isothermal elastic compliance tensor and thermal expansivity tensor. The isothermal and isentropic stiffness tensors, the Grüneisen tensor and anisotropic seismic velocities can be derived from these properties. To illustrate the use of the formulations, anisotropic models are parametrized using numerical simulations of cubic periclase and experimental data on orthorhombic San Carlos olivine.
Green’s Function of a Subgraph of a Complete Graph
Authors: Lin Yong , Ngai Sze-Man , Yau Shing-Tung
Published: May 2022

By using heat kernel expansions for the Laplacian on a subgraph of a complete graph, we obtain formal expansions for the Green function of the Laplacian on a subgraph of a complete graph. We study this formal series for both the cases that the subgraph is complete and not complete, and in both cases, we obtain precise information about the convergence of the series.
On the Numerical Dimension of Calabi–Yau 3-Folds of Picard Number 2
Authors: Hoff Michael , Stenger Isabel
Published: May 2022

We show that for any smooth Calabi–Yau threefold $X$ of Picard number $2$ with infinite birational automorphism group, the numerical dimension $\kappa _\sigma $ of the extremal rays of the movable cone of $X$ is $\frac {3}{2}$. Furthermore, we provide new examples of Calabi–Yau threefolds of Picard number $2$ with infinite birational automorphism group.
PrankWeb 3: accelerated ligand-binding site predictions for experimental and modelled protein structures
Authors: Jakubec David , Skoda Petr , Krivak Radoslav , Novotny Marian , Hoksza David
Published: May 2022

Knowledge of protein–ligand binding sites (LBSs) enables research ranging from protein function annotation to structure-based drug design. To this end, we have previously developed a stand-alone tool, P2Rank, and the web server PrankWeb (https://prankweb.cz/) for fast and accurate LBS prediction. Here, we present significant enhancements to PrankWeb. First, a new, more accurate evolutionary conservation estimation pipeline based on the UniRef50 sequence database and the HMMER3 package is introduced. Second, PrankWeb now allows users to enter UniProt ID to carry out LBS predictions in situations where no experimental structure is available by utilizing the AlphaFold model database. Additionally, a range of minor improvements has been implemented. These include the ability to deploy PrankWeb and P2Rank as Docker containers, support for the mmCIF file format, improved public REST API access, or the ability to batch download the LBS predictions for the whole PDB archive and parts of the AlphaFold database.
United States: highlights of legal and tax differences of statutory foundations and private foundations
Authors: Georgiev Lyubomir , Walsh Gregory , Hunter Chelsea , Lasky Rebecca , Sanders Olga
Published: May 2022

The article approaches the analysis of foundations primarily from an entity classification and tax point of view. First, the authors address the various options how a foreign foundation can be classified under U.S. tax law. Subsequently, the authors take a closer look at U.S. statutory foundations, which now exist under the laws of New Hampshire and Wyoming. In a third section, they explain the concept of a private foundation, which under U.S. federal tax law refers to a tax-exempt charitable organization. These private foundations are compared with statutory foundations with regard to their legal and tax law differences. The authors come to the conclusion that the ability to tailor a statutory foundation to meet specific needs using an entity with legal personality is very likely its greatest attribute that founders find attractive.
Comparing the Liver Safety Profiles of 4 Next-Generation CGRP Receptor Antagonists to the Hepatotoxic CGRP Inhibitor Telcagepant Using Quantitative Systems Toxicology Modeling
Authors: Woodhead Jeffrey L , Siler Scott Q , Howell Brett A , Watkins Paul B , Conway Charles
Published: May 2022

Calcitonin gene-related peptide (CGRP) signaling inhibitors have shown efficacy in both the acute and preventive treatment of migraine. Telcagepant, a first-generation CGRP receptor antagonist, was effective but failed in clinical trials due to hepatotoxicity. Subsequently, although 4 next-generation CGRP receptor antagonists (rimegepant, zavegepant, atogepant, and ubrogepant) were being advanced into late-stage clinical trials, due to telcagepant’s failure, more confidence in the liver safety of these compounds was needed. DILIsym v6A, a quantitative systems toxicology (QST) model of drug-induced liver injury (DILI), was used to model all 5 compounds and thus to compare the 4 next-generation CGRP receptor antagonists to telcagepant. In vitro experiments were performed to measure the potential for each compound to inhibit bile acid transporters, produce oxidative stress, and cause mitochondrial dysfunction. Physiologically based pharmacokinetic models were produced for each compound in order to appropriately estimate liver exposure. DILIsym predicted clinical elevations of liver enzymes and bilirubin for telcagepant, correctly predicting the observed DILI liability of the first-generation compound. By contrast, DILIsym predicted that each of the 4 next-generation compounds would be significantly less likely to cause DILI than telcagepant. Subsequent clinical trials have validated these predictions for each of the 4 compounds, and all 3 of the compounds submitted to FDA to date (rimegepant, ubrogepant, and atogepant) have since been approved by the FDA with no warning for hepatotoxicity. This work demonstrates the potential for QST modeling to prospectively differentiate between hepatotoxic and nonhepatotoxic molecules within the same class.
Detection and Characterization of Viruses and Viroids in Diospyros Species from Florida, U.S.A.
Authors: Velez-Climent Maria , Soria Patricia , Dey Kishore , Mou De-Fen , McVay John , Bahder Brian W.
Published: May 2022

Persimmon is a hardwood tree in the genus Diospyros that is commonly cultivated for its fruit in Eurasia and North America. Recent advances in metagenomics have resulted in the discovery of multiple novel viruses and viroids infecting persimmon trees in Asia and Europe. Recent survey work revealed the presence of viral pathogens in North America in Diospyros kaki, the Japanese persimmon, which is the most widely cultivated species globally. In this study, a survey of both D. kaki and D. virginiana, a native to the southeastern United States, was conducted to evaluate the viral infection status of these species in Florida. It was determined that out of the eight viral pathogens known from persimmon, six are present in Florida: apple fruit crinkle viroid (AFCVd), persimmon cryptic virus (PeCV), persimmon viroid (PeVd), persimmon virus A (PeVA), persimmon virus B (PeVB), and persimmon viroid 2 (PeVd2). In D. kaki, the most common viroid was PeVd and the most common virus was PeVA. In D. virginiana, PeVd2 was the most common viroid and PeVA was the most common virus. Most of the infections in D. kaki were mixed infections, while most infections in D. virginiana were single infections. The findings of this study are the first evidence of viral pathogens in Florida in D. kaki and the first evidence of these pathogens in native D. virginiana in North America. Future efforts should focus on vector surveys and transmission experiments.
Identifying US Plastic Surgery Training Programs that Effectively Establish Gender and Ethnically Diverse Faculty
Authors: Onyekaba Ginikanwa , Mauch Jaclyn T. , McAuliffe Phoebe B. , Diatta Fortunay , Mellia Joseph A. , Morris Martin P. , Murphy Alexander I. , Broach Robyn B. , Fischer John P. , Butler Paris D.
Published: May 2022

Background:

Successful strategies to improve the representation of female and ethnically underrepresented in medicine (UIM) physicians among US plastic and reconstructive surgery (PRS) faculty have not been adequately explored. Accordingly, we aimed to identify programs that have had success, and in parallel gather PRS program directors’ and chiefs/chairs’ perspectives on diversity recruitment intentionality and strategies.

Methods:

We conducted a cross-sectional analysis of the demographic composition of female and UIM faculty of PRS residency training programs. Separate lists of programs in the top quartile for female and UIM faculty representation were collated. Additionally, a 14-question survey was administered to program directors and chiefs/chairs of all 99 Accreditation Council for Graduate Medical Education-accredited PRS residency programs. The questions comprised three domains: (1) demographic information; (2) perceptions about diversity; and (3) recruitment strategies utilized to diversify faculty.

Results:

Female and UIM faculty representation ranged from 0% to 63% and 0% to 50%, respectively. Survey responses were received from program directors and chiefs/chairs of 55 institutions (55% response rate). Twenty-five (43%) respondents felt their program was diverse. Fifty-one (80%) respondents felt diversity was important to the composition of PRS faculty. Active recruitment of diverse faculty and the implementation of a diversity, equity, and inclusion committee were among the most frequently cited strategies to establish a culturally sensitive and inclusive environment.

Conclusions:

These findings reveal that female and UIM representation among US PRS faculty remains insufficient; however, some programs have had success through deliberate and intentional implementation of diversity, equity, and inclusion strategies.
Healthcare Professionals' Electroencephalography Competency: A Disconnect Between Self-Assessment and Objective Testing
Authors: Linnavuori Elina , Leino-Kilpi Helena , Stolt Minna
Published: May 2022

BACKGROUND: The role of the healthcare professional (HCP) in performing high-quality electroencephalography (EEG) is critical to ensuring accurate results. This study analyzes HCPs' subjectively and objectively assessed EEG competence to provide information on their EEG competence and competence needs for the development of their education and training. METHODS: The study was a descriptive cross-sectional study. The target group of the study was HCPs working in the clinical neurophysiology departments of university hospitals in Finland. The research data were collected using the EEG Competence instrument created for this research. The instrument consisted of a self-assessment section and a knowledge test component. RESULTS: The participants (N = 65; response rate, 81%) consisted of 34 registered nurses and 31 laboratory technologists. In the self-assessment section, the highest mean score was in patient observation (mean, 4.6) and the lowest was in EEG theoretical knowledge (mean, 3.9). In the test section, most of the respondents (73.8%) answered all questions correctly (maximum, 6 points). There was a positive correlation between age, work experience, own satisfaction with EEG competence, and subjective self-assessment. Those familiar with EEG guidelines and who participated in training days assessed their competence as significantly better (P < .05). Respondents who read EEG-related literature on their own identified artifacts better (P = .005). CONCLUSIONS: Laboratory technologists' and registered nurses' subjectively and objectively assessed EEG competence was high. In the future, the EEG competence instrument should be developed further, and more research is needed to assess its psychometric properties to provide more information on HCPs' competence in the diagnostic process.
Transgender Mastectomy
Authors: Bruce Madeleine K. , Joseph Walter J. , Grunwaldt Lorelei , Nguyen Vu T. , De La Cruz Carolyn
Published: May 2022

Background

Chest masculinization surgeries are one of the most common gender-affirming procedures performed. There is a need for better understanding of the risk of breast cancer and postsurgical screening in female to male (FtM) individuals. This study aimed to evaluate the incidence of high-risk pathologic findings in FtM transgender patients undergoing gender-affirming chest reconstructive surgery.

Methods

Medical records were reviewed from all FtM patients undergoing gender-affirming chest reconstructive surgery from January 2010 to February 2021 by 3 plastic surgeons at the University of Pittsburgh Medical Center. Relative risk of malignant progression was used to stratify pathologic data. Subsequent management of atypical, in situ, and invasive pathology were recorded.

Results

A total of 318 patients were included in this study; the average age at surgery was 24.6 ± 8.1 years. Eighty-six patients (27%) had a family history of breast and/or ovarian cancer. Overall, 21 patients (6.6%) had some increased risk of breast cancer: 17 (5.3%) had proliferative lesions, mean age 38.2 ± 12.4 years; 2 had atypical ductal hyperplasia, ages 33.4 and 38.3 years; and 2 had invasive ductal carcinoma, ages 35.4 and 40.6 years.

Conclusions

In this study, we found that 6.6% of FtM transgender patients undergoing top surgery had an elevated risk of breast cancer, with 1.2% of patients having a greater than 2 times risk of breast cancer. These results highlight the importance of appropriate preoperative screening as well as pathological analysis of surgical specimens to help guide clinical care. The authors advocate for a thorough breast cancer risk assessment before surgery for all patients, as well as using pathologic findings to guide postoperative cancer screening and follow-up.
Inter-scanner brain MRI volumetric biases persist even in a harmonized multi-subject study of multiple sclerosis
Authors: Clark Kelly A. , O’Donnell Carly M. , Elliott Mark A. , Tauhid Shahamat , Dewey Blake E. , Chu Renxin , Khalil Samar , Nair Govind , Sati Pascal , DuVal Anna , Pellegrini Nicole , Bar-Or Amit , Markowitz Clyde , Schindler Matthew K. , Zurawski Jonathan , Calabresi Peter A. , Reich Daniel S. , Bakshi Rohit , Shinohara Russell T. ,   the NAIMS Cooperative
Published: May 2022

Background/Purpose

Multicenter study designs involving a variety of MRI scanners have become increasingly common. However, these present the issue of biases in image-based measures due to scanner or site differences. To assess these biases, we imaged 11 volunteers with multiple sclerosis (MS) with scan and rescan data at 4 sites.

Materials and Methods

Images were acquired on Siemens or Philips scanners at 3-tesla. Automated white matter lesion detection and whole brain, gray and white matter, and thalamic volumetry were performed, as well as expert manual delineations of T1 and T2 (FLAIR) lesions. Random effect and permutation-based nonparametric modeling was performed to assess differences in estimated volumes within and across sites.

Results

Random effect modeling demonstrated model assumption violations for most comparisons of interest. Non-parametric modeling indicated that site explained > 50% of the variation for most estimated volumes. This expanded to > 75% when data from both Siemens and Philips scanners were included. Permutation tests revealed significant differences between average inter- and intra-scanner differences in most estimated brain volumes (P < .05). The automatic activation of spine coil elements during some acquisitions resulted in a shading artifact in these images. Permutation tests revealed significant differences between thalamic volume measurements from acquisitions with and without this artifact.

Conclusion

Differences in brain volumetry persisted across MR scanners despite protocol harmonization. These differences were not well explained by variance component modeling; however, statistical innovations for mitigating inter-scanner differences show promise in reducing biases in multi-center studies of MS.
Design and validation of the first family of photo-activatable ligands for melatonin receptors
Authors: Somalo-Barranco Gloria , Serra Carme , Lyons David , Piggins Hugh D. , Jockers Ralf , Llebaria Amadeu
Published: May 2022

Melatonin is a neurohormone released in a circadian manner with peak levels during the night. In mammals, melatonin mediates its effects mainly through G protein-coupled MT1 and MT2 receptors. Drugs acting on melatonin receptors are indicated for circadian rhythm- and sleep-related disorders and major depression. Pharmacological tools to study the activation of these receptors with high temporal resolution are lacking. Here, we synthesized a family of light-activatable caged melatonin compounds by covalently attaching o-nitrobenzyl (o-NB) or coumarin photocleavable groups to the N-position of melatonin. All caged compounds showed the expected decrease in binding affinity for MT1 and MT2. Among them, the o-NB derivative MCS-0382 showed the best uncaging and biological properties upon light activation with a significant increase (2.5 log left-shift) in affinity and potency in melatonin receptor binding and signaling, respectively. Generation of biologically active melatonin from MCS-0382 was further demonstrated by its ability to modulate the excitation of SCN neurons in rat brain slices. MCS-0382 is now available to study melatonin effects in a temporally controlled manner in cellular and physiological settings.
Spinal cord extracts of amyotrophic lateral sclerosis spread TDP-43 pathology in cerebral organoids
Authors: Tamaki Yoshitaka , Ross Jay P. , Alipour Paria , Catoire Hélène , Rochefort Daniel , Urushitani Makoto , Takahashi Ryosuke , Sonnen Joshua A. , Stifani Stefano , Dion Patrick A. , Rouleau Guy A.
Published: May 2022

Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative disorder caused by progressive loss of motor neurons and there is currently no effective therapy. Cytoplasmic mislocalization and aggregation of TAR DNA-binding protein 43 kDa (TDP-43) within the CNS is a pathological hallmark in sporadic ALS and prion-like propagation of pathogenic TDP-43 is thought to be implicated in disease progression. However, cell-to-cell transmission of pathogenic TDP-43 in the human CNS has not been confirmed experimentally.

Here we used induced pluripotent stem cells (iPSCs)-derived cerebral organoids as recipient CNS tissue model that are anatomically relevant human brain. We injected postmortem spinal cord protein extracts individually from three non-ALS or five sporadic ALS patients containing pathogenic TDP-43 into the cerebral organoids to validate the templated propagation and spreading of TDP-43 pathology in human CNS tissue.

We first demonstrated that the administration of spinal cord extracts from an ALS patient induced the formation of TDP-43 pathology that progressively spread in a time-dependent manner in cerebral organoids, suggesting that pathogenic TDP-43 from ALS functioned as seeds and propagated cell-to-cell to form de novo TDP-43 pathology. We also reported that the administration of ALS patient-derived protein extracts caused astrocyte proliferation to form astrogliosis in cerebral organoids, reproducing the pathological feature seen in ALS. Moreover, we showed pathogenic TDP-43 induced cellular apoptosis and that TDP-43 pathology correlated with genomic damage due to DNA double-strand breaks.

Thus, our results provide evidence that patient-derived pathogenic TDP-43 can mimic the prion-like propagation of TDP-43 pathology in human CNS tissue. Our findings indicate that our assays with human cerebral organoids that replicate ALS pathophysiology have a promising strategy for creating readouts that could be used in future drug discovery efforts against ALS.
Next generation sequencing analysis of gastric cancer identifies the leukemia inhibitory factor receptor (LIFR) as a driving factor in gastric cancer progression and as a predictor of poor prognosis
Authors: Di Giorgio Cristina , Marchianò Silvia , Marino Elisabetta , Biagioli Michele , Roselli Rosalinda , Bordoni Martina , Bellini Rachele , Urbani Ginevra , Zampella Angela , Distrutti Eleonora , Donini Annibale , Graziosi Luigina , Fiorucci Stefano
Published: May 2022

Gastric cancer (GC) is the third cause of cancer-related-death worldwide. Nevertheless, because GC screening programs are not cost-effective, most patients receive diagnosis in the advanced stages, when surgical options are limited because the presence of diffuse disease. Peritoneal dissemination occurs in approximately one third of patients with GC and is a strong predictor of poor outcome. Despite the clinical relevance, biological and molecular mechanisms underlying the formation of peritoneal metastasis in GC remain poorly defined. To investigate this point, we conducted a high-throughput sequencing of transcriptome expression in paired samples of normal and neoplastic gastric mucosa in 31 GC patients with or without peritoneal carcinomatosis. The RNAseq analysis led to the discovery of a group of highly upregulated or downregulated genes that were differentially modulated in patients with peritoneal disease in comparison to GC patients without peritoneal involvement. Among these genes the leukemia inhibitory factor receptor (LIFR) and the one cut domain family member (ONECUT)2 were the only two genes that predicted survival at univariate statistical analysis. Because LIFR was the highest regulated gene we have further assessed whether this receptor plays a mechanistic role in GC dissemination. For this purpose, we have first assessed the expression of LIF, a member of IL-6 cytokine family, and LIFR in GC cell lines. Our results demonstrate that exposure of MKN45 cells to LIF, promoted a concentration-dependent proliferation and epithelial-mesenchymal transition (EMT) as shown by modulation of E-cadherin/vimentin gene expression along with JAK and STAT 3 phosphorylation and acquisition of a migratory phenotype. These features were reversed by in vitro treatment with a LIFR antagonist. Together, these data provide support to the notion that development of LIF/LIFR inhibitors might have a role in the treatment of GC.
Nitrogen palaeo-isoscapes: Changing spatial gradients of faunal δ15N in late Pleistocene and early Holocene Europe
Authors: Reade Hazel , Tripp Jennifer A. , Frémondeau Delphine , Sayle Kerry L. , Higham Thomas F.G. , Street Martin , Stevens Rhiannon E.
Published: May 2022

Nitrogen isotope (δ15N) analysis of animal tissue is widely used in archaeology and palaeoecology to investigate diet and ecological niche. Data interpretations require an understanding of nitrogen isotope compositions at the base of the food web (baseline δ15N). Significant variation in animal δ15N has been recognised at various spatiotemporal scales and linked to changes both in baseline δ15N and animal ecology. Isoscapes (models of isotope spatial variation) have proved a useful tool for investigating spatial variability in biogeochemical cycles in present-day marine and terrestrial ecosystems, but so far, their application to palaeo-data has been limited. Here, we present time-sliced nitrogen isoscapes for late Pleistocene and early Holocene Europe (c. 50,000 to 10,000 years BP) using herbivore collagen δ15N data. This period covers the Last Glacial-Interglacial Transition, during which significant variation in the terrestrial nitrogen cycle occurred. Our results show clear changes in spatial gradients of δ15N through time. Prediction of the lowest faunal δ15N values in northern latitudes after, rather than during, the Last Glacial Maximum is consistent with the Late Glacial Nitrogen Excursion (LGNE). We consider the potential of incorporating climatic covariate data into isoscape models but find their inclusion does not improve model performance. These findings have implications for investigating the drivers of the LGNE, which has been linked to increased landscape moisture and permafrost thaw, and for understanding changing isotopic baselines, which are fundamental for studies investigating diets, niche partitioning, and migration of higher trophic level animals.
Molecular insights into the effect of hexanediol on FUS phase separation
Authors: Zheng Tongyin , Wake Noah , Weng Shuo-Lin , Perdikari Theodora Myrto , Murthy Anastasia C. , Mittal Jeetain , Fawzi Nicolas L.
Published: May 2022

1,6-hexanediol disrupts many phase-separated condensates in cells and in test tubes. In this study, we use a combination of microscopy, nuclear magnetic resonance (NMR) spectroscopy, molecular simulation, and biochemical assays to probe how alkanediols suppress phase separation and why certain isomers are more effective. Alkanediols of different lengths and configurations are all capable of disrupting phase separation of the RNA-binding protein Fused in Sarcoma (FUS), though potency varies depending on both geometry and hydrophobicity, which we measure directly. Alkanediols induce a shared pattern of changes to the protein chemical environment though to differing extents. Consistent with the view that alkanediols disrupt phase separation driven by hydrophobic groups, they decrease the thermal stability of a model globular protein. Conversely, 1,6-hexanediol does not disrupt charge-mediated phase separation, such as FUS RGG-RNA and poly-lysine/poly-aspartic acid condensates. All-atom simulations show that hydroxyl groups in alkanediols mediate interaction with protein backbone and polar amino acid side chains, while the aliphatic chain allows contact with hydrophobic and aromatic residues, providing a molecular picture of how amphiphilic interactions disrupt FUS phase separation.
Incorporating uniparental markers and demographic information in kinship analysis
Authors: Liu Jin-Xian , Li Meng-Yu
Published: May 2022

Knowledge of kinship relations between members of wild populations is of great importance in ecological and conservation genetic studies. The bi-parentally inherited autosomal markers has been the Golden Standard in kinship analysis. However, analysis of kin relationship can be challenging in wild populations. The uni-parentally inherited markers and population demographic information can be helpful for identifying false-positive in kinship analysis. Here we showed how incorporating uniparental genetic and demographic information can improve the correct classification rate of kinship analyses by reanalyzing data of a recent study published in Science Advances. The application of next generation high-throughput sequencing to address fundamental ecological questions is of immense benefit to the field of molecular ecology, which could also generate uniparentally inherited organelle genomes together with nuclear data. We strongly recommended that uniparental genetic markers and demographic information be seriously considered in kinship analyses of wild populations.
Skull and scalp segmentation in neonatal cerebral MRI using subject-specific probability models
Authors: Hokmabadi Elham , Abrishami Moghaddam Hamid , Mohtasebi Mehrana , Kazemloo Amirreza , Gity Masume , Wallois Fabrice
Published: May 2022

This study presents a new approach for segmenting cranial bones in magnetic resonance images (MRIs) acquired from neonates in the gestational age range of 39 to 42 weeks. the approach uses subject-specific probability maps of the skull and scalp, created from atlas computed tomography (CT) images taken retrospectively from neonates in the same age range. the method also uses a subject-specific probability map of cerebrospinal fluid (CSF), constructed from retrospective atlas MRIs. To build skull, scalp, and CSF probability maps, a subject-specific bimodal MR-CT neonatal head template is employed. In the next step, the subject-specific probability maps are fed to the expectation maximization algorithm in conjunction with Markov random field method implemented in FSL software to segment the skull and scalp from the input MR image. The results of the proposed method were evaluated through various experiments. First, we employed our method as a brain tissue extractor and compared its results with public methods such as the Brain Extraction Tool (BET) and Brain Surface Extractor (BSE). Second, we calculated the similarity in shape between the frontal and occipital sutures (which had been reconstructed from segmented cranial bones) and the ground truth. For this purpose, modified versions of the Dice similarity coefficient (DSC) were adopted and used. Finally, retrospective data including MRI and CT images obtained from the same neonate within a short time interval were used. After aligning the two images, the DSC and modified Hausdorff distance (MHD) were used to compare the similarity of the cranial bones in the MR and CT images. Furthermore, the anterior fontanel size was compared to the normal size reported for neonates in the same age range. Cranial bone thickness was calculated and compared to normal values reported for healthy neonates. The results of these experiments demonstrated the success of our segmentation method. The algorithm for creating subject-specific atlases is publicly accessible through a graphical user interface atmedvispy.ee.kntu.ac.ir.
Single neurons and networks in the claustrum integrate input from widespread cortical sources
Authors: Shelton Andrew M , Oliver David K , Lazarte Ivan P , Grimstvedt Joachim S , Kapoor Ishaan , Swann Jake A , Ashcroft Caitlin A , Williams Simon N , Conway Niall , Tir Selma , Robinson Amy , Peirson Stuart N , Akam Thomas , Kentros Clifford , Witter Menno P , Butt Simon JB , Packer Adam M
Published: May 2022

The claustrum is thought to be one of the most highly interconnected forebrain structures but its organizing principles have yet to be fully explored at the level of single neurons. Here, we investigated the identity, connectivity, and activity of identified claustrum neurons to understand how the structure's unique convergence of input and divergence of output support binding information streams. We found that neurons in the claustrum communicate with each other across efferent projection-defined modules which were differentially innervated by sensory and frontal cortical areas. Individual claustrum neurons were responsive to inputs from more than one cortical region in a cell-type and projection-specific manner, particularly between areas of frontal cortex. In vivo imaging of claustrum axons revealed responses to both unimodal and multimodal sensory stimuli. Finally, chronic claustrum silencing specifically reduced animals' sensitivity to multimodal stimuli. These findings support the view that the claustrum is a fundamentally integrative structure, consolidating information from around the cortex and redistributing it following local computations.
Modelling the within-host spread of SARS-CoV-2 infection, and the subsequent immune response, using a hybrid, multiscale, individual-based model. Part I: Macrophages
Authors: Rowlatt C. F. , Chaplain M. A. J. , Hughes D. J. , Gillespie S. H. , Dockrell D. H. , Johannessen I. , Bowness R.
Published: May 2022

Individual responses to SARS-CoV-2 infection vary significantly, ranging from mild courses of infection that do not require hospitalisation to the development of disease which not only requires hospitalisation but can be fatal. Whilst many immunological studies have revealed fundamental insights into SARS-CoV-2 infection and COVID-19, mathematical and computational modelling can offer an additional perspective and enhance understanding. The majority of mathematical models for the within-host spread of SARS-CoV-2 infection are ordinary differential equations, which neglect spatial variation. In this article, we present a hybrid, multiscale, individual-based model to study the within-host spread of SARS-CoV-2 infection. The model incorporates epithelial cells (each containing a dynamical model for viral entry and replication), macrophages and a subset of cytokines. We investigate the role of increasing initial viral deposition, increasing delay in type I interferon secretion from epithelial cells (as well as the magnitude of secretion), increasing macrophage virus internalisation rate and macrophage activation, on the spread of infection.
A new device for continuous non-invasive measurements of leaf water content using NIR-transmission allowing dynamic tracking of water budgets
Authors: Kaiser Hartmut
Published: May 2022

Leaf water content (LWC) permanently fluctuates under variable transpiration rate and sap flow and influences e.g. stomatal responses and osmotic adjustment of plant cells. Continuous recordings of LWC are therefore central for the investigation of the regulatory networks stabilizing leaf hydration. Available measurement methods, however, either influence local hydration, interfere with the local leaf micro-environment or cannot easily be combined with other techniques. To overcome these limitations a non-invasive sensor was developed which uses light transmission in the NIR range for precise continuous recordings of LWC. For LWC measurements the transmission ratio of two NIR wavelengths was recorded using a leaf-specific calibration. Pulsed measurement beams enabled measurements under ambient light conditions. The contact-free sensor allows miniaturization and can be integrated into many different experimental settings. Example measurements of LWC during disturbances and recoveries of leaf water balance show the high precision and temporal resolution of the LWC sensor and demonstrate possible method combinations. Simultaneous measurements of LWC and transpiration allows to calculate petiole influx informing about the dynamic leaf water balance. With simultaneous measurements of stomatal apertures the relevant stomatal and hydraulic processes are covered, allowing insights into dynamic properties of the involved positive and negative feed-back loops.
Realizing employee and organizational performance gains through electronic human resource management use in developing countries
Authors: Nyathi Musa , Kekwaletswe Ray
Published: May 2022

Purpose

The purpose of this paper is to propose and test a model designed to realize employee and organizational performance gains in developing economies.

Design/methodology/approach

Data were collected through a survey involving 35 organizations using electronic human resource management (e-HRM) systems. A purposive sampling technique was employed. Regression analysis making use of Process macro in Statistical Package for the Social Sciences (SPSS) was used to analyze the data.

Findings

Despite its infancy in African countries, e-HRM use has a positive effect on employee and organizational performance. The organization-wide gains are enhanced through employee performance mediation.

Practical implications

Electronic-HRM use, complemented by human resource best practices that impact positively on individual performance, is likely to enhance organizational performance gains. Employee performance mediation effect is likely to further enhance the effect of e-HRM usage on organizational performance.

Originality/value

This study represents a first attempt to examine the role of employee performance as an intervening variable in the relationship between e-HRM use and organizational performance. The findings bring into attention the role of organizational members' performance in explaining organizational performance gains. The findings also result in a model that should lead to increased employee and organizational performance.
The effect of succession on corporate governance reform under the Chinese clan culture context
Authors: Wang Linchuan , Gao Qianying , Wu Cisheng
Published: May 2022

Purpose

The fundamental component of Confucian culture is clan culture, which stresses that family ties are the most important of all social relationships and have an essential impact on the governance model of family firms in Southeast Asian countries, especially in China. This study investigates complex relationships among family firm succession and corporate governance reform in the context of Chinese clan culture.

Design/methodology/approach

Drawing upon the analysis of altruistic behavior and conflict in succession process in family firm, the study uses a moderation model to capture the relationships between succession and governance reform in the context of clan culture. This study conducts an empirical study on 295 Chinese listed family firms that initiated intergenerational succession from 2008 to 2018 to test the model.

Findings

The empirical results suggest that the different stages of the succession will positively affect the family firm's governance reform, whether it is the stage in which the successor takes over the firm or the stage in which the successor completely controls the firm. Furthermore, the succession-governance reform relationship is negatively moderated by the clan concept of the actual controller.

Originality/value

This paper fulfills an identified need to study how succession in the family firm can accelerate corporate governance reform (transition from relation-based governance to rule-based governance). The research results provide evidence from the firm-level under the Chinese clan culture context to understand the complex relationship between succession and corporate governance.
Single versus multiple salesforce go-to-market strategy: the impact of sales orientation on conflict, salesperson-owned loyalty and buyer-exit propensity
Authors: Anaza Nwamaka A. , Rutherford Brian N. , Wu Gavin Jiayun , Bhattarai Ashok
Published: May 2022

Purpose

Drawing on the organizational buying decision-making framework, the purpose of this study is to investigate how sales orientation (SOCO) affects buyers’ conflict, salesperson-owned loyalty and buyers’ propensity to end a supply relationship when selling firms use a single versus multiple salesforce go-to-market strategy.

Design/methodology/approach

Survey data was analyzed with a sample of organizational buyers. Confirmatory factor analysis and structural equation modeling were used to analyze the data.

Findings

Findings reveal that a selling firm’s go-to-market salesforce strategy moderates certain relational aspects of the buyer–salesperson relationship, consequently influencing a buyer’s decision to end a supply relationship.

Research limitations/implications

Empirically, these findings indicate that the effects of selling orientation on conflict, salesperson-owned loyalty and exit intentions are not only based on the salesperson’s efforts but are conditional on the selling firm’s go-to-market strategy, particularly with the implementation of multiple salespeople selling to a particular industrial buyer.

Practical implications

These results suggest that a salesforce go-to-market strategy conveys serious consequences on buying decisions. Given that a go-to-market strategy involving multiple salespeople impacts the buyer’s relationship with the selling firm to a greater degree, managerial oversight must remain present when selling firms decide to pursue such a go-to-market strategy.

Originality/value

The empirical investigation of a salesforce go-to-market strategy is an original pursuit. Specifically, this study shows that while it is critical that buying and selling firms monitor buyer–salesperson relationships as the basis for supply partnerships, these exchanges are largely contingent on the selling firm’s go-to-market strategy.
Human capital futures: an educational perspective
Authors: Bottrill Chris
Published: May 2022

Purpose

Education institutions can be slow to react to the changes that are happening in human capital development content and delivery. This article highlights some of the shifts that robotics, artificial intelligence (AI) and access to information are having on jobs in tourism and the future of work. It explores the ways in which the tourism education sector can respond.

Design/methodology/approach

This paper draws upon content shared at several conferences and webinars addressing the future of work and the education delivery methods from experts and commentators on the subject. This was augmented by research conducted by global tourism associations, the World Economic Forum and other global associations and supported with secondary data from recent media and online content providers.

Findings

By highlighting emerging trends in the sector and skills to thrive in the fourth industrial revolution, we can identify what education should focus on during this period of transition and uncertainty. We need to capitalize on the digital delivery skills we have developed due to COVID-19 and build new content and accessible learning approaches.

Originality/value

There are many uncertainties about the future of work and the way that a rapidly digitized education delivery approach has and will affect tourism education in the future. This article is aimed to generate further thought and dialogue by identifying changes and raising points about what we are effective at in public post-secondary education and what we need to capitalize on and adapt to in the future. The core question posed is that if the tourism and hospitality workforce and work environment has changed, has, or can, tourism and hospitality training and education change as well?