bluuebunny/crossref_metadata_2025 huggingface dataset:
Neural vulnerability and hurricane-related media predict posttraumatic stress in youth
Authors: Dick Anthony Steven , Silva Karina , Gonzalez Raul , Sutherland Matthew T. , Laird Angela R. , Thompson Wesley K. , Tapert Susan F. , Squeglia Lindsay M. , Gray Kevin M. , Nixon Sara Jo , Cottler Linda B. , La Greca Annette M. , Gurwitch Robin H. , Comer Jonathan S.
Published: August 2020

As natural disasters increase in frequency and severity1, 2, mounting evidence reveals that their human toll extends beyond death, injury, and loss. Posttraumatic stress (PTS) can be common among directly exposed individuals, and children are particularly vulnerable3, 4. Curiously, PTS can even be found among youth far removed from harm’s way, and media-based exposure may partially account for this phenomenon5–8. Unfortunately, susceptibility to media effects has been difficult to characterize because most research is initiated post-event, precluding examination of pre-disaster factors. In this study, we mitigate this issue with data from nearly 400 9-to 11-year-old children collected prior to and after Hurricane Irma. We evaluate whether preexisting neural patterns moderate associations between hurricane experiences and later Irma-related PTS. We show that “dose” of bothobjectiveexposure and Irma-relatedmediaexposure predicted Irma-related PTS, the latter even among children dwelling thousands of kilometers away from the hurricane. Furthermore, we show, using pre-hurricane functional magnetic resonance imaging data, that neural responses in brain regions associated with anxiety and stress confer particular vulnerability to the psychological effects of hurricane exposure among certain children. Surprisingly, this was even the case for media exposure– we found that that right amygdala reactivity to fearful stimuli moderated the association between Irma-related media exposure and PTS symptoms, with the media-PTS association strongest for children showing pre-hurricane heightened amygdala reactivity to Fear vs Neutral Faces. In contrast, in bilateral orbitofrontal cortex and left parahippocampal gyrus, children showing a weak response to the Fear condition relative to the Neutral condition were especially susceptible to PTS as a result of Irma-related media exposure. Collectively, these findings run counter to outdated “bullseye” models of disaster exposure that assume negative effects are narrowly circumscribed around a disaster’s geographic epicenter9. In contrast, for some youth with measurable preexisting vulnerability, consumption of extensive disaster-related media appears to offer an alternative pathway to disaster exposure that transcends geography and objective risk. This preventable exposure should be considered in disaster-related mental health efforts.
Evolution of Single Gyroid Photonic Crystals in Bird Feathers
Authors: Saranathan Vinodkumar , Narayanan Suresh , Sandy Alec , Dufresne Eric R. , Prum Richard O.
Published: August 2020

Vivid, saturated structural colors are conspicuous and important features of many animals. A rich diversity of three-dimensional periodic photonic nanostructures is found in the chitinaceous exoskeletons of invertebrates. Three-dimensional photonic nanostructures have been described in bird feathers, but they are typically quasi-ordered. Here, we report bi-continuous single gyroid β-keratin and air photonic crystal networks in the feather barbs of blue-winged leafbirds(Chloropsis cochinchinensis sensu lato), which have evolved from ancestral quasi-ordered channel-type nanostructures. Self-assembled avian photonic crystals may serve as inspiration for multi-functional applications, as they suggest efficient, alternative routes to single gyroid synthesis at optical length-scales, which has been experimentally elusive.
Clinal genomic analysis reveals strong reproductive isolation across a steep habitat transition in stickleback fish
Authors: Haenel Quiterie , Oke Krista B. , Laurentino Telma G. , Hendry Andrew P. , Berner Daniel
Published: August 2020

How ecological divergence causes strong reproductive isolation between populations in close geographic contact remains poorly understood at the genomic level. We here study this question in a stickleback population pair adapted to contiguous, ecologically different lake and stream habitats. Dense clinal whole-genome sequence data reveal numerous regions fixed for alternative alleles over a distance of just a few hundred meters. This strong polygenic adaptive divergence must constitute a genome-wide barrier to gene flow because a steep cline in allele frequencies is observed across the entire genome, and because the cline center co-localizes with the habitat transition. Simulations confirm that such strong reproductive isolation can be maintained by polygenic selection despite high dispersal and small per-locus selection coefficients. Finally, comparing samples from the cline center before and after an unusual ecological perturbation demonstrates the fragility of the balance between gene flow and selection. Overall, our study highlights the efficacy of divergent selection in maintaining reproductive isolation without physical isolation, and the analytical power of studying speciation at a fine eco-geographic and genomic scale.
The E3 ubiquitin ligase Mind bomb 1 enhances nuclear import of viral DNA by inactivating a virion linchpin protein that suppresses exposure of virion pathogen-associated molecular patterns
Authors: Bauer Michael , Gomez-Gonzalez Alfonso , Suomalainen Maarit , Hemmi Silvio , Greber Urs F.
Published: August 2020

In eukaryotic cells, genomes from incoming DNA viruses mount two opposing reactions, viral gene expression and innate immune response, depending on genome exposure (uncoating) to either RNA-polymerases or DNA sensors. Here we show that adenovirus particles contain a tunable linchpin protein with a dual function: response to host cues for scheduled DNA release into the nucleus, and innate immunity suppression by preventing unscheduled DNA release. Scheduled DNA release required the proteasome and ubiquitination of the viral core protein V. Cells lacking the E3 ligase Mind bomb 1 (Mib1) were resistant to wild-type adenovirus infection. Viruses lacking protein V or bearing non-ubiquitinable protein V, however, readily infected Mib1 knockout cells, yet were less infectious than wild-type virus. Their genomes were poorly imported into the nucleus and remained uncoated in the cytosol, thereby enhancing chemokine and interferon production through the DNA sensor cGAS. Our data uncover how the ubiquitin-proteasome system controls the function of a virion linchpin protein suppressing pathogen-associated molecular patterns and triggers viral DNA uncoating at the nuclear pore complex for nuclear import and infection.
Asymmetric nuclear division of neural stem cells contributes to the formation of sibling nuclei with different identities
Authors: Roubinet Chantal , White Ian J. , Baum Buzz
Published: August 2020

Cellular diversity in multicellular organisms is often generated via asymmetric divisions. In the fly, for example, neural stem cells divide asymmetrically to generate a large self-renewing stem cell and a smaller sibling that differentiates. Efforts to understand how these different cell fates are generated have focused on the asymmetric segregation of cortically-localised transcription factors at division, which preferentially enter single daughter cell nuclei to change their fate. However, we find that the nuclear compartment in these cells remains intact throughout mitosis and is asymmetrically inherited, giving rise to sibling nuclei that differ profoundly in size, envelope composition and fate markers. These data reveal the importance of considering nuclear remodelling during stem cell divisions, and show how daughter cell fates depend on the coordination of the asymmetric inheritance of cortical fate markers with asymmetric nuclear division.
Establishment of murine hybridoma cells producing antibodies against spike protein of SARS-CoV-2
Authors: Antipova Nadezhda V. , Larionova Tatyana D. , Shakhparonov Michail I. , Pavlyukov Marat S.
Published: August 2020

In 2020 the world faced the pandemic of COVID-19 - severe acute respiratory syndrome caused by a new type of coronavirus named SARS-CoV-2. To stop the spread of the disease, it is crucial to create molecular tools allowing to investigate, diagnose and treat COVID-19. One of such tools are monoclonal antibodies (mAbs). In this study we describe the development of hybridoma cells that can produce mouse mAbs against receptor binding domain of SARS-CoV-2 spike (S) protein. These mAbs are able to specifically detect native and denaturized S protein in all tested applications including immunoblotting, immunofluorescence staining and enzyme-linked immunosorbent assay. In addition, we showed that the obtained mAbs decreased infection rate of human cells by SARS-CoV-2 pseudovirus particles inin vitroexperiments. Finally, we determined the amino acid sequence of light and heavy chains of the mAbs. This information will allow to use the corresponding peptides to establish genetically engineered therapeutic antibodies. To date multiple mAbs against SARS-CoV-2 proteins have been established, however due to the restrictions caused by pandemic, it is imperative to have a local source of the antibodies suitable for researches and diagnostics of COVID-19. Moreover, as each mAb has a unique binding sequence, bigger sets of various antibodies will allow to detect SARS-CoV-2 proteins even if the virus acquires novel mutations.
Contingency and chance erase necessity in the experimental evolution of ancestral proteins
Authors: Xie Victoria Cochran , Pu Jinyue , Metzger Brian P.H. , Thornton Joseph W. , Dickinson Bryan C.
Published: August 2020

To understand why evolution produced the biological systems that exist today, we must know how important chance, contingency, and necessity were during history. Previous observations suggest that each of these modes of causality affects evolution in various settings, but their relative roles and interactions are not well characterized because they have never been systematically assessed in a single system or on a timescale relevant to evolutionary history. To this end, we reconstructed ancestral B-cell-lymphoma-2-family proteins and developed a continuous evolution method to select for defined protein-protein interaction specificities. By repeatedly evolving a series of ancestral proteins to acquire specificities that occurred during history, we show that contingency steadily overwhelms chance and erases necessity as the primary cause of sequence variation in proteins over long phylogenetic timescales. As a result, evolutionary trajectories launched from distant starting points are essentially unpredictable, even under strong and identical selection pressures. Genetic dissection of the outcomes shows that chance arises because numerous sets of mutations can alter specificity at any point in time, while contingency arises because historical substitutions change these sets. Patterns of variation in extant protein sequences are therefore largely the idiosyncratic product of a particular course of unpredictable historical events.
App-based symptom tracking to optimize SARS-CoV-2 testing strategy using machine learning
Authors: Dantas Leila F. , Peres Igor T. , Bastos Leonardo S. L. , Marchesi Janaina F. , de Souza Guilherme F. G. , Gelli João Gabriel M. , Baião Fernanda A. , Maçaira Paula , Hamacher Silvio , Bozza Fernando A.
Published: September 2020

Background

Tests are scarce resources, especially in low and middle-income countries, and the optimization of testing programs during a pandemic is critical for the effectiveness of the disease control. Hence, we aim to use the combination of symptoms to build a regression model as a screening tool to identify people and areas with a higher risk of SARS-CoV-2 infection to be prioritized for testing.

Materials and Methods

We applied machine learning techniques and provided a visualization of potential regions with high densities of COVID-19 as a risk map. We performed a retrospective analysis of individuals registered in “Dados do Bem”, an app-based symptom tracker in use in Brazil.

Results

From April 28 to July 16, 2020, 337,435 individuals registered their symptoms through the app. Of these, 49,721 participants were tested for SARS-CoV-2 infection, being 5,888 (11.8%) positive. Among self-reported symptoms, loss of smell (OR[95%CI]: 4.6 [4.4 - 4.9]), fever (2.6 [2.5 - 2.8]), and shortness of breath (2.1 [1.6-2.7]) were associated with SARS-CoV-2 infection. Our final model obtained a competitive performance, with only 7% of false-negative users among the predicted as negatives (NPV = 0.93). From the 287,714 users still not tested, our model estimated that only 34.5% are potentially infected, thus reducing the need for extensive testing of all registered users. The model was incorporated by the “Dados do Bem” app aiming to prioritize users for testing. We developed an external validation in the state of Goias and found that of the 465 users selected, 52% tested positive.

Conclusions

Our results showed that the combination of symptoms might predict SARS-Cov-2 infection and, therefore, can be used as a tool by decision-makers to refine testing and disease control strategies.
24 People, one test: Boosting test efficiency using pooled serum antibody testing for SARS-CoV-2
Authors: Nessler Stefan , Franz Jonas , van der Meer Franziska , Kolotourou Konstantina , Venkataramani Vivek , Hasan Chalid , Pollok-Kopp Beatrix , Zautner Andreas E. , Stadelmann Christine , Weig Michael , Pöhlmann Stefan , Hoffmann Markus , Riggert Joachim
Published: September 2020

Background

The global pandemic of COVID-19 (coronavirus disease 2019) is caused by the novel coronavirus SARS-CoV-2 (severe acute respiratory syndrome coronavirus 2), with different prevalence rates across countries and regions. Dynamic testing strategies are mandatory to establish efficient mitigation strategies against the disease; to be cost effective, they should adapt to regional prevalences. Seroprevalence surveys that detect individuals who have mounted an immune response against COVID-19 will help to determine the total number of infections within a community and improve the epidemiological calculations of attack and case fatality rates of the virus. They will also inform about the percentage of a population that might be immune against re-infections.

Methods

We developed a sensitive and specific cell-based assay to detect conformational SARS-CoV-2 spike (SARS-2-S) S1 antibodies in human serum, and have cross-evaluated this assay against two FDA-approved SARS-CoV-2 antibody assays. We performed pseudovirus neutralization assays to determine whether sera that were rated antibody-positive in our assay were able to specifically neutralize SARS-2-S. We pooled up to 24 sera and assessed the group testing performance of our cell-based assay. Group testing was further optimized by Monte Carlo like simulations and prospectively evaluated.

Findings

Highly significant correlations could be established between our cell-based assay and commercial antibody tests for SARS-CoV-2. SARS-2-S S1 antibody-positive sera neutralized SARS-2-S but not SARS-S, and were sensitively and specifically detected in pools of 24 samples. Monte Carlo like simulations demonstrated that a simple two-step pooling scheme with fixed pool sizes performed at least equally as well as Dorfman’s optimal testing across a wide range of antibody prevalences.

Interpretation

We demonstrate that a cell-based assay for SARS-2-S S1 antibodies qualifies for group testing of neutralizing anti-SARS-2-S antibodies. The assay can be combined with an easily implemented algorithm which greatly expands the screening capacity to detect anti-SARS-2-S antibodies across a wide range of antibody prevalences. It will thus improve population serological testing in many countries.

Funding

This work was supported by the Bundesministerium für Bildung und Forschung within the network project RAPID (risk assessment in pre-pandemic respiratory infectious diseases [grant number 01KI1723D, S.P.]).
Epidemiological Association of Cannabinoid- and Drug- Exposures and Sociodemographic Factors with Limb Reduction Defects Across USA 1989-2016: A Geotemporospatial and Causal Inference Study
Authors: Reece Albert Stuart , Hulse Gary Kenneth
Published: September 2020

Reports of major limb defects after prenatal cannabis exposure (PCE) in animals and of human populations in Hawaii, Europe and Australia raise the question of whether the increasing use of cannabis in USA might be spatiotemporally associated with limb reduction rates (LRR) across USA. Geotemporospatial analysis conducted in R. LRR was significantly associated with cannabis use and THC potency and demonstrated prominent cannabis-use quintile effects. In final lagged geospatial models interactive terms including cannabinoids were highly significant and robust to adjustment. States in which cannabis was not legalized had a lower LRR (4.28 v 5.01 /10,000 live births, relative risk reduction = −0.15, (95%C.I. −0.25, −0.02), P=0.021). 37-63% of cases are estimated to not be born alive; their inclusion strengthened these associations. Causal inference studies using inverse probabilty-weighted robust regression and e-values supported causal epidemiological pathways. Findings apply to several cannabinoids, are consistent with pathophysiological and causal mechanisms, are exacerbated by cannabis legalization and demonstrate dose-related intergenerational sequaelae.

Highlights

Limb reduction rates (LRR) were associated with cannabis use, and THC potency

These relationships were robust to adjustment for ethic and economic covariates

They were maintained at geospatiotemporal regression

LRR elevated as stillborn and aborted cases were considered

Criteria of causality was fulfilled
A model assessing potential benefits of isolation and mass testing on COVID-19: the case of Nigeria
Authors: Chirove Faraimunashe , Madubueze Chinwendu E. , Chazuka Zviiteyi , Madubueze Sunday
Published: September 2020

We consider a model with mass testing and isolation mimicking the current policies implemented in Nigeria and use the Nigerian daily cumulative cases to calibrate the model to obtain the optimal mass testing and isolation levels. Mathematical analysis was done and important thresholds such the peak size relation and final size relation were obtained. Global stability analysis of the disease-free equilibrium indicated that COVID-19 can be eradicated provided that and unstable otherwise. Results from simulations revealed that an increase in mass testing and reduction of transmission from isolated individuals are associated with benefits of increasing detected cases, lowering peaks of symptomatic cases, increase in self-isolating cases, decrease in cumulative deaths and decrease in admissions into monitored isolation facilities in the case of Nigeria.
Modeling SARS-CoV-2 infectionin vitrowith a human intestine-on-chip device
Authors: Guo Yaqiong , Luo Ronghua , Wang Yaqing , Deng Pengwei , Zhang Min , Wang Peng , Zhang Xu , Cui Kangli , Tao Tingting , Li Zhongyu , Chen Wenwen , Zheng Yongtang , Qin Jianhua
Published: September 2020

Coronavirus disease 2019 (COVID-19) caused by severe acute respiratory syndrome coronavirus (SARS-CoV-2) has given rise to a global pandemic. The gastrointestinal symptoms of some COVID-19 patients are underestimated. There is an urgent need to develop physiologically relevant model that can accurately reflect human response to viral infection. Here, we report the creation of a biomimetic human intestine infection model on a chip system that allows to recapitulate the intestinal injury and immune response induced by SARS-CoV-2, for the first time. The microengineered intestine-on-chip device contains human intestinal epithelium (co-cultured human intestinal epithelial Caco-2 cells and mucin secreting HT-29 cells) lined in upper channel and vascular endothelium (human umbilical vein endothelial cells, HUVECs) in a parallel lower channel under fluidic flow condition, sandwiched by a porous PDMS membrane coated with extracellular matrix (ECM). At day 3 post-infection of SARS-CoV-2, the intestine epithelium showed high susceptibility to viral infection and obvious morphological changes with destruction of intestinal villus, dispersed distribution of mucus secreting cells and reduced expression of tight junction (E-cadherin), indicating the destruction of mucous layer and the integrity of intestinal barrier caused by virus. Moreover, the endothelium exhibited abnormal cell morphology with disrupted expression of adherent junction protein (VE-cadherin). Transcriptional analysis revealed the abnormal RNA and protein metabolism, as well as activated immune responses in both epithelial and endothelial cells after viral infection (e.g., up-regulated cytokine genes, TNF signaling and NF-kappa B signaling-related genes). This bioengineeredin vitromodel system can mirror the human relevant pathophysiology and response to viral infection at the organ level, which is not possible in existingin vitroculture systems. It may provide a promising tool to accelerate our understanding of COVID-19 and devising novel therapies.
Efficient isolation of protoplasts from rice calli with pause points and its application in transient gene expression and genome editing assays
Authors: Poddar Snigdha , Tanaka Jaclyn , Cate Jamie H. D. , Staskawicz Brian , Cho Myeong-Je
Published: September 2020

An efficientin vivotransient transfection system using protoplasts is an important tool to study gene expression, metabolic pathways, and multiple mutagenesis parameters in plants. Although rice protoplasts can be isolated from germinated seedlings or cell suspension culture, preparation of those donor tissues can be inefficient, time consuming, and laborious. Additionally, the lengthy process of protoplast isolation and transfection needs to be completed in a single day. Here we report a protocol for isolation of protoplasts directly from rice calli, without using seedlings or suspension culture. The method is developed to employ discretionary pause points during protoplast isolation and prior to transfection. Protoplasts maintained within a sucrose cushion partway through isolation, for completion on a subsequent day, per the first pause point, are referred to as S protoplasts. Fully isolated protoplasts maintained in MMG solution for transfection on a subsequent day, per the second pause point, are referred to as M protoplasts. Both S and M protoplasts, 1 day after initiation of protoplast isolation, had minimal loss of viability and transfection efficiency compared to protoplasts 0 days after isolation. S protoplast viability decreases at a lower rate over time than that of M protoplasts and can be used with added flexibility for transient transfection assays and time-course experiments. The protoplasts produced by this method are competent for transfection of both plasmids and ribonucleoproteins (RNPs). Cas9 RNPs were used to demonstrate the utility of these protoplasts to assay genome editingin vivo. The current study describes a highly effective and accessible method to isolate protoplasts from callus tissue induced from rice seeds. This method utilizes donor materials that are resource-efficient and easy to propagate, permits convenience via pause points, and allows for flexible transfection days after protoplast isolation. It provides an advantageous and useful platform for a variety ofin vivotransient transfection studies in rice.
Dysregulation of hippocampal adult-born immature neurons disrupts a brain-wide network for spatial memory
Authors: Bao Hechen , Hu Zhiqiang , Lee Sung-ho , Kolagani Ramya , Chao Tzu-Hao Harry , Luo Yan-Jia , Ban Woomi , Sullivan Heather Anne , Gamero-Alameda Sergio , Lybrand Zane R. , Yu Yuguo , Hsieh Jenny , Wickersham Ian R , Brenner Steven E , Shih Yen-Yu Ian , Song Juan
Published: September 2020

Mounting evidence suggests that cognitive deficits associated with various neurological disorders may arise in part from a small population of dysregulated adult-born neurons in the dentate gyrus (DG). How these dysregulated adult-born neurons contribute to brain-wide network maladaptation and subsequent cognitive deficits remains unknown. Using an established mouse model with a small number of time-stamped dysregulated adult-born immature neurons and spatial memory deficits, we performed resting state functional magnetic resonance imaging and found that approximately 500 deficient immature neurons (<0.1% of total DG granule neurons) are sufficient to induce a significant decrease in the functional connectivity between DG and insular cortex (IC), two brain regions without direct anatomical connections. Furthermore, using a combination of rabies-based retrograde tracing andin vivofiber photometry recording, we demonstrated that dysregulated adult-born neurons induce aberrant activity and synchrony in local hippocampal CA3 and CA1 regions, as well as distal medial-dorsal thalamus and IC regions during a spatial memory process. These results suggest that a few hundred dysregulated adult-born immature neurons can impact brain-wide network dynamics across several anatomically discrete regions and collectively contribute to impaired cognitive functions.
The lateral periaqeductal gray and its role in controlling the opposite behavioral choices of predatory hunting and social defense
Authors: Marín-Blasco Ignacio Javier , José Rangel Miguel , Baldo Marcus Vinicius C. , Motta Simone Cristina , Canteras Newton Sabino
Published: September 2020

Evasion from imminent threats and prey attack are opposite behavioral choices critical to survival. Curiously, the lateral periaqueductal gray (LPAG) has been implicated in driving both responses. The LPAG responds to social threats and prey hunting while also drives predatory attacks and active defense. However, the LPAG neural mechanisms mediating these behaviors remain poorly defined. Here, we investigate how the LPAG mediates the choices of predatory hunting and evasion from a social threat. Pharmacogenetic inhibition in Fos DD-Cre mice of neurons responsive specifically to insect predation (IP) or social defeat (SD) revealed that distinct neuronal populations in the LPAG drive the prey hunting and evasion from social threats. We show that the LPAG provides massive glutamatergic projection to the lateral hypothalamic area (LHA). Optogenetic inhibition of the LPAG-LHA pathway impaired IP but did not alter escape/attack ratio during SD. We also found that pharmacogenetic inhibition of LHAGABAneurons impaired IP, but did not change evasion during SD. The results suggest that the LPAG control over evasion to a social attack may be regarded as a stereotyped response depending probably on glutamatergic descending projections. On the other hand, the LPAG control over predatory behavior involves an ascending glutamatergic pathway to the LHA that likely influences LHAGABAneurons driving predatory attack and prey consumption. The LPAG-LHA path supposedly provides an emotional drive for prey hunting and, of relevance, may conceivably have more widespread control on the motivational drive to seek other appetitive rewards.
Data-driven analysis of facial thermal responses to an emotional movie reveals consistent stimulus-locked physiological changes
Authors: Sonkusare Saurabh , Breakspear Michael , Pang Tianji , Nguyen Vinh Thai , Frydman Sascha , Guo Christine Cong , Aburn Matthew J.
Published: September 2020

Facial infra-red imaging (IRI) is a contact-free technique complimenting the traditional psychophysiological measures to characterize physiological profile. However, its full potential in affective research is arguably unmet due to the analytical challenges it poses. Here we acquired facial IRI data, facial expressions and traditional physiological recordings (heart rate and skin conductance) from healthy human subjects whilst they viewed a 20-minute-long unedited emotional movie. We present a novel application of motion correction and the results of spatial independent component analysis of the thermal data. Three distinct spatial components are recovered associated with the nose, the cheeks and a respiratory component. We first benchmark this methodology against a traditional region-of-interest based technique. We then show significant correlation of all the physiological responses across subjects, including the thermal signals, suggesting common dynamic shifts in emotional state induced by the movie. Finally, we show that thermal responses were significantly anti-correlated with the positive emotional content of the movie thus an index of emotionally-driven physiological response. In sum, this study introduces an innovative approach to analyse facial IRI data and highlights the potential of thermal imaging to robustly capture emotion-related changes in ecological contexts.
Simulating the outcome of amyloid treatments in Alzheimer’s disease from imaging and clinical data
Authors: Abi Nader Clément , Ayache Nicholas , Frisoni Giovanni B. , Robert Philippe , Lorenzi Marco ,   for the Alzheimer’s Disease Neuroimaging Initiative
Published: September 2020

In this study we investigate a novel quantitative instrument for the development of intervention strategies for disease modifying drugs in Alzheimer’s disease. Our framework is based on the modeling of the spatio-temporal dynamics governing the joint evolution of imaging and clinical biomarkers along the history of the disease, and allows the simulation of the effect of intervention time and drug dosage on the biomarkers’ progression. When applied to multi-modal imaging and clinical data from the Alzheimer’s Disease Neuroimaging Initiative our method enables to generate hypothetical scenarios of amyloid lowering interventions. The results quantify the crucial role of intervention time, and provide a theoretical justification for testing amyloid modifying drugs in the pre-clinical stage. Our experimental simulations are compatible with the outcomes observed in past clinical trials, and suggest that anti-amyloid treatments should be administered at least 7 years earlier than what is currently being done in order to obtain statistically powered improvement of clinical endpoints.
Identification and evolution of Cas9 tracrRNAs
Authors: Dooley Shane K. , Baken Erica K. , Moss Walter , Howe Adina , Young Joshua K.
Published: September 2020

Cas9 trans-activating CRISPR RNAs (tracrRNAs) form distinct structures essential for target recognition and cleavage and dictate exchangeability between orthologous proteins. As non-coding RNAs that are often apart from the CRISPR array, their identification can be arduous. In this paper, a new bioinformatic method for the detection of Cas9 tracrRNAs is presented. The approach utilizes a co-variance model (CM) based on both sequence homology and predicted secondary structure to locate tracrRNAs. This method predicts a tracrRNA for 98% of CRISPR-Cas9 systems identified by us. The identified tracrRNAs exhibit wide variation in sequence identity, however, CM analyses allow 94.7% to be categorized into just 10 related groups. Finally, association between Cas9 amino acid sequence-based phylogeny and tracrRNA secondary structure is evaluated, revealing strong evidence that secondary structure is evolutionarily conserved among Cas9 lineages. Altogether, our findings provide insight into Cas9 tracrRNA evolution and efforts to characterize the tracrRNA of new Cas9 systems.
Chemistry of transition-metal complexes containing functionalized phosphines: synthesis and structural analysis of rhodium(I) complexes containing allyl and cyanoalkylphosphines
Authors: Atencio Reinaldo , Chacón Gustavo , Mendoza Lisbeth , González Teresa , Bruno-Colmenarez Julia , Rosales Merlin , Alexander Briceño , Ocando-Mavárez Edgar
Published: August 2020

A series of related acetylacetonate–carbonyl–rhodium compounds substituted by functionalized phosphines has been prepared in good to excellent yields by the reaction of [Rh(acac)(CO)2] (acac is acetylacetonate) with the corresponding allyl-, cyanomethyl- or cyanoethyl-substituted phosphines. All compounds were fully characterized by 31P, 1H, 13C NMR and IR spectroscopy. The X-ray structures of (acetylacetonato-κ2
O,O′)(tert-butylphosphanedicarbonitrile-κP)carbonylrhodium(I), [Rh(C5H7O2)(CO)(C8H13N2)] or [Rh(acac)(CO)(tBuP(CH2CN)2}] (2b), (acetylacetonato-κ2
O,O′)carbonyl[3-(diphenylphosphanyl)propanenitrile-κP]rhodium(I), [Rh(C5H7O2)(C15H14N)(CO)] or [Rh(acac)(CO){Ph2P(CH2CH2CN)}] (2h), and (acetylacetonato-κ2
O,O′)carbonyl[3-(di-tert-butylphosphanyl)propanenitrile-κP]rhodium(I), [Rh(C5H7O2)(C11H22N)(CO)] or [Rh(acac)(CO){tBu2P(CH2CH2CN)}] (2i), showed a square-planar geometry around the Rh atom with a significant trans influence over the acetylacetonate moiety, evidenced by long Rh—O bond lengths as expected for poor π-acceptor phosphines. The Rh—P distances displayed an inverse linear dependence with the coupling constants J
P-Rh and the IR ν(C[triple-bond]O) bands, which accounts for the Rh—P electronic bonding feature (poor π-acceptors) of these complexes. A combined study from density functional theory (DFT) calculations and an evaluation of the intramolecular H...Rh contacts from X-ray diffraction data allowed a comparison of the conformational preferences of these complexes in the solid state versus the isolated compounds in the gas phase. For 2b, 2h and 2i, an energy-framework study evidenced that the crystal structures are mainly governed by dispersive energy. In fact, strong pairwise molecular dispersive interactions are responsible for the columnar arrangement observed in these complexes. A Hirshfeld surface analysis employing three-dimensional molecular surface contours and two-dimensional fingerprint plots indicated that the structures are stabilized by H...H, C...H, H...O, H...N and H...Rh intermolecular interactions.
Forecasting China's energy intensity by using an improved DVCGM (1, N) model considering the hysteresis effect
Authors: Meng Zhaosu , Liu Xiaotong , Yin Kedong , Li Xuemei , Guo Xinchang
Published: September 2020

Purpose

The purpose of this paper is to examine the effectiveness of an improved dummy variables control grey model (DVCGM) considering the hysteresis effect of government policies in China's energy intensity (EI) forecasting.

Design/methodology/approach

Energy consumption is considered as an important driver of economic development. China has introduced policies those aim at the optimization of energy structure and EI. In this study, EI is forecasted by an improved DVCGM, considering the hysteresis effect of energy-saving policies of the government. A nonlinear optimization method based on particle swarm optimization (PSO) algorithm is constructed to calculate the hysteresis parameter. A one-step rolling mechanism is applied to provide input data of the prediction model. Grey model (GM) (1, N), DVCGM (1, N) and ARIMA model are applied to test the accuracy of the improved DVCGM (1, N) model prediction.

Findings

The results show that the improved DVCGM provides reliable results and works well in simulation and predictions using multivariable data in small sample size and time-lag virtual variable. Accordingly, the improved DVCGM notes the hysteresis effect of government policies and significantly improves the prediction accuracy of China's EI than the other three models.

Originality/value

This study estimates the EI considering the hysteresis effect of energy-saving policies in China by using an improved DVCGM. The main contribution of this paper is to propose a model to estimate EI, considering the hysteresis effect of energy-saving policies and improve forecasting accuracy.
Disability and influence in job interviews
Authors: Ameri Mason , Kurtzberg Terri , Schur Lisa , Kruse Douglas
Published: September 2020

Purpose

This purpose of this paper is to explore to efficacy of influence tactics at the outset of a job interview. Across three empirical studies, five influence tactics were manipulated during a simulated job interview to explore first impressions for candidates with or without a visible disability.

Design/methodology/approach

Participants viewed videos of candidates (either in a wheelchair or not) responding to the opening question in a job interview by using one of five influence tactics (i.e. revealing a strong alternative, setting a numerical anchor, demonstrating approachability through imperfections, presenting hard skills that described job-related competencies or presenting soft skills including connecting well with and leading others). Perceptions of trustworthiness, fit for the current job and perceived appropriate salary amount were rated.

Findings

Results show that, in general, tactics that might have beneficial effects when used at later moments, including the use of a strong alternate, anchor or imperfection display, may instead harm first impressions of anyone. When discussing specific skills, hard skills helped in both cases. However, the presentation of soft skills helped only the non-disabled job candidate. Trustworthiness acted as a mediator for most of these relationships in both populations.

Originality/value

Results provide insight into how the use of these tactics very early in an interaction unfolds. Further, parsing the use of influence tactics into their effects on specific populations (such as people with disabilities) allows us to better understand the conditions under which they may help or hurt perceptions of employability.
The impact of job content on employability and job performance in public organizations
Authors: Marzec Izabela , Austen Agata , Frączkiewicz-Wronka Aldona , Zacny Bogna
Published: August 2020

Purpose

The increased expectations regarding job performance accompanied by changes in employment relationships in public organizations require special concern for the employability enhancement of their workers. Literature on the subject points out the importance of job content in the context of employability enhancement. The purpose of this paper is to answer the following question: what are the relationships between job variety, the learning value of the job, employability and job performance?

Design/methodology/approach

The paper presents the results of a survey which was carried out in 2016. The sample consisted of 566 pairs, i.e. employees and their immediate supervisors in 147 public organizations which provide key public services in Poland. A model of the relationships between job variety, the learning value of the job, employability and job performance was proposed and tested using path analysis and structural equation modeling (SEM).

Findings

It was found that both job variety and the learning value of the job were positively connected to employability, which mediated their relationships with job performance. However, the analysis revealed that the examined predictors not only affected employee work outcomes indirectly, through their impact on employability, but also directly influenced the quality of job performance.

Originality/value

The study has provided empirical evidence regarding the relationships between job content, employability and job performance, which was hitherto absent from public organizations. An original conclusion from the research is that employability enhancement brings positive results for both employees and organizations.
Digital love – inviting doubt into the relationship: the duality of digitalization effects on business relationships
Authors: Hadjikhani Annoch Isa , Lindh Cecilia
Published: September 2020

Purpose

This study aims to hypothesize that the implementation of information technology (IT) in industrial business relationships entails both positive and negative effects for the relationship’s continuation. The purpose is to study the digitalization of business relationships with a focus on effects on commitment in context with uncertainty and cooperation.

Design/methodology/approach

Hypotheses are tested with data from 353 customer relationships in the industrial market. The model suggests the impact of IT on business relationship commitment.

Findings

The results show that IT use in industrial relationships has a direct impact on commitment, as well as an indirect effect via uncertainty and cooperation, which both can increase as a result of IT use. When IT use increases uncertainty, it negatively impacts commitment, and when it increases cooperation, the effect on commitment is positive.

Research limitations/implications

IT use in industrial relationships has a direct impact on commitment, as well as an indirect effect via uncertainty and cooperation, which both can increase as a result of IT use. When IT use increases uncertainty, it negatively impacts commitment, and when it increases cooperation, the effect on commitment is positive.

Practical implications

Awareness of the effect of IT use and the factors involved entails working with cooperative activities to counteract the negative impact there may be if the IT leads to increased uncertainty. Companies need to have knowledge regarding the effect of IT use in each of their business relationships to manage them according to their given situation.

Originality/value

This study contributes to industrial marketing by demonstrating that digitalization can increase uncertainty and cooperation (differently), and they have different effects on commitment, thus that there is a “bright,” as well as “dark” side to it, evident in the business relationship dynamics.
The Kathmandu Valley's indigenous practices of safeguarding heritage: an assessment of present-day challenges
Authors: Maharjan Monalisa , Barata Filipe Themudo
Published: September 2020

Purpose

The purpose of this paper is to understand the traditional practices of safeguarding intangible cultural heritage (ICH) through “Guthi”, that is continued by the indigenous community of Kathmandu Valley. It explores the ancient system as a management practice rather than just a social costume. By analyzing existing laws and policies relevant to intangible heritage of Nepal, it aims to find scope for the Guthi in the formal heritage conservation practice and its relevancy in present context of 2003 Convention, where community participation plays a pivotal role.

Design/methodology/approach

To study the traditional method of safeguarding heritage “Guthi system”, the case of “Yehya Punhi Festival” also known as “Indra Jatra” of Kathmandu was taken as a case. Qualitative research methodology was used to study various sub festivals within Yenya, its functions, funding mechanism and its way of continuity by Guthi. Review of various legislations associated with the heritage of Nepal, published and unpublished official documents as well as international conventions and recommendations were done. In addition to semi-structured interview with Guthi members, experts and locals; the observation of eight days long festival was also conducted,

Findings

The study found that traditional Guthi system still holds a strong value in the social structure and safeguarding of traditional practices even with negative impact of modernization. Guthi is the main reason for the continuity of the Yenya Punhi festival, along with various associated rituals, while the national legislations of Nepal do not recognize Guthi as a safeguarding practice. Traditional practice could be a way forward for implementation of 2003 convention in Nepal when Nepal has already ratified the convention. Guthi could be sustainable way of safeguarding heritage if integrated well in the formal heritage practices.

Originality/value

Guthi has been studied by many researchers from anthropological perspectives and even conservation for tangible heritage but not as a mechanism of safeguarding ICH. Guthi could be one of the excellent examples of Safeguarding Intangible Heritage and could also be a good recipe for management with community participation, sustainability and indigenous knowledge. More research and publication like this is necessary to push government to look into homegrown solutions than implementing new management plan.
Digital humanities research: interdisciplinary collaborations, themes and implications to library and information science
Authors: Su Fangli , Zhang Yin , Immel Zachary
Published: September 2020

Purpose

The purpose of this paper is to examine the structure, patterns and themes of interdisciplinary collaborations in the digital humanities (DH) research through the application of social network analysis and visualization tools.

Design/methodology/approach

The sample includes articles containing DH research in the Web of Science Core Collection as of December 2018. First, co-occurrence data representing collaborations among disciplinary were extracted from the subject category. Second, the descriptive statistics, network indicators and interdisciplinary communities were calculated. Third, the research topics of different interdisciplinary collaboration communities based on system keywords, author keywords, title and abstracts were detected.

Findings

The findings reveal that while the scope of disciplines involved in DH research is broad and evolving over time, most interdisciplinary collaborations are concentrated among several disciplines, including computer science, library and information science, linguistics and literature. The study further uncovers some communities based on closely collaborating disciplines and the evolving nature of such interdisciplinary collaboration communities over time. To better understand the close collaboration ties, the study traces and analyzes the research topics and themes of the interdisciplinary communities. Finally, the implications of the findings for DH research are discussed.

Originality/value

This study applied various informetric methods and tools to reveal the collaboration structure, patterns and themes among disciplinaries in DH research.
Enhancing policies and measurements of family business: macro, meso or micro analysis
Authors: Ratten Vanessa , Jones Paul
Published: September 2020

Purpose

The purpose of this article is to highlight new directions that are needed in family business research particularly in light of the covid-19 pandemic and changing societal conditions.

Design/methodology/approach

This editorial is a review of the main issues discussed in the special journal issue regarding family businesses at the macro, meso and micro level. This approach enables a better understanding about the future research and practical implications for family business in the new economy characterised by substantial changes resulting from the covid-19 pandemic.

Findings

The findings suggest that family business studies need to incorporate new industry and societal contexts that have not previously been examined in sufficient detail in family business studies. This includes focusing more on the sport industry that is characterised by many family businesses.

Originality/value

This editorial for the special journal issue is amongst the first to discuss the role of the covid-19 crisis in impacting family business.