bluuebunny/crossref_metadata_2025 huggingface dataset:
Somatic junctions connect microglia and developing neurons
Authors: Cserép Csaba , Schwarcz Anett D. , Pósfai Balázs , László Zsófia I. , Kellermayer Anna , Nyerges Miklós , Lele Zsolt , Katona István , Dénes Ádám
Published: March 2021

Microglia are the resident immune cells of the brain with multiple homeostatic and regulatory roles. Emerging evidence also highlights the fundamental transformative role of microglia in brain development. While tightly controlled, bi-directional communication between microglia and neuronal progenitors or immature neurons has been postulated, the main sites of interaction and the underlying mechanisms remain elusive. By using correlated light and electron microscopy together with super-resolution imaging, here we provide evidence that microglial processes form specialized nanoscale contacts with the cell bodies of developing and immature neurons throughout embryonic, early postnatal and adult neurogenesis. These early developmental contacts are highly reminiscent to somatic purinergic junctions that are instrumental for microglia-neuron communication in the adult brain. We propose that early developmental formation of somatic purinergic junctions represents an ideal interface for microglia to monitor the status of developing neurons and to direct prenatal, early postnatal and adult neurogenesis.
Respiration aligns perception with neural excitability
Authors: Kluger Daniel S. , Balestrieri Elio , Busch Niko A. , Gross Joachim
Published: March 2021

Recent studies from the field of interoception have highlighted the link between bodily and neural rhythms during action, perception, and cognition. The mechanisms underlying functional body-brain coupling, however, are poorly understood, as are the ways in which they modulate behaviour. We acquired respiration and human magnetoencephalography (MEG) data from a near-threshold spatial detection task to investigate the trivariate relationship between respiration, neural excitability, and performance. Respiration was found to significantly modulate perceptual sensitivity as well as posterior alpha power (8 – 13 Hz), a well-established proxy of cortical excitability. In turn, alpha suppression prior to detected vs undetected targets underscored the behavioural benefits of heightened excitability. Notably, respiration-locked excitability changes were maximised at a respiration phase lag of around - 30° and thus temporally preceded performance changes. In line with interoceptive inference accounts, these results suggest that respiration actively aligns sampling of sensory information with transient cycles of heightened excitability to facilitate performance.
A tau class Glutathione-S-Transferase (OsGSTU5) acts as a negative regulator of VirE2 interaction with T-DNA duringAgrobacteriuminfection in rice
Authors: Tiwari Madhu , Gautam Neelam , Indoliya Yuvraj , Kidwai Maria , Mishra Arun Kumar , Chakrabarty Debasis
Published: March 2021

DuringAgrobacterium-mediated transformation (AMT), T-DNA along with several virulence proteins like VirD2, VirE2, VirE3, VirD5, and VirF enter into the plant cytoplasm. VirE2 is supposed to serve as single-stranded DNA binding (SSB) protein and assist the cytoplasmic trafficking of T-DNA inside the host cell. In the present study, a rice glutathione-S-transferase (OsGSTU5) that interacts with VirE2 protein in plant cytoplasm has been identified. OsGSTU5 is observed to be involved in post-translational glutathionylation of VirE2 protein (gVirE2).In silicoanalysis revealed that ‘gVirE2+ssDNA’ complex is structurally less stable than ‘VirE2+ ssDNA’ complex. The gel shift activity confirms the attenuated SSB property of gVirE2 over VirE2 protein underin vitrocondition. Moreover, knock-down and overexpressionOsGSTU5phenotypes of rice showed increased and decreased T-DNA expression, respectively afterAgrobacteriuminfection. The present finding convincingly establishes the role of OsGSTU5 as defense protein in rice that can further serve as an important target for modulation of AMT efficiency in rice.
Patterns and mechanisms underlying ecoregion delineation in North American freshwater plants
Authors: Alahuhta Janne , García–Girón Jorge
Published: March 2021

Abstract

Aim

Biogeographical regionalisations are actively studied in different ecosystems, because they increase our understanding on fundamental broad□scale patterns and can help us in the establishment of conservation areas. Thus, we studied how well existing freshwater ecoregions describe geographical delineation for inland water plants and which ecogeographical gradients explain them.

Location

North America, excluding Mexico and remote islands.

Taxon

Freshwater vascular plants of all taxa and different functional groups.

Methods

Using newly available fine–grained data on freshwater plant distributions, we calculated internal homogeneity and cross–boundary heterogeneity among neighbouring ecoregions. We further integrated measures of community dissimilarity to assess whether the degree of within–ecoregion homogeneity and distinctness are driven by their relationships to species replacements and richness differences, and explored how a complex suite of ecogeographical mechanisms and plant life forms affect ecoregion delineation using spatially explicit regression routines.

Results

We found a clear geographical patterning of ecoregion robustness for North American freshwater plants, with their communities being more internally homogeneous and more similar to one another in polar and subtropical inland waters. Surprisingly, the degree of internal homogeneity and ecoregion distinctness were almost equally driven by species replacements and richness differences. Considering different life forms, ecoregion delineation performed best for emergent and floating–leaved plants. Finally, within–ecoregion homogeneity and distinctness were best explained by annual mean temperature and terrain ruggedness, respectively, with mean water alkalinity, ecoregion area and Late Quaternary Ice Age legacies having supplementary effects.

Main conclusions

Our findings emphasise that geographical regionalisations founded on a particular organismal group are not applicable for all taxa. Our study is a promising starting point for further investigations of geographical delineations for different freshwater taxa. These updated regionalisations can then be used for conserving different biotas in freshwaters, which are currently among the most threatened ecosystems in the world.

Statement of significance

In biogeographical regionalisation biota is categorized to meaningful geographical units, such as ecoregions. However, ecoregions delineated for a particular group of organisms may not be applicable to another assemblages. We studied how ecoregions founded on fish are suitable for freshwater plants across North America. Our findings suggest that these ecoregions did not show consistent robustness for freshwater plants in North America. This study is a promising starting point for further investigations of geographical delineations for different freshwater taxa, having also value in conservation planning and management.
Adjustment of spurious correlations in co-expression measurements from RNA-Sequencing data
Authors: Hsieh Ping-Han , Lopes-Ramos Camila Miranda , Zucknick Manuela , Sandve Geir Kjetil , Glass Kimberly , Kuijjer Marieke Lydia
Published: March 2021

1

Gene co-expression measurements are widely used in computational biology to identify coordinated expression patterns across a group of samples, which may indicate that these genes are controlled by the same transcriptional regulatory program, or involved in common biological processes. Gene co-expression is generally estimated from RNA-Sequencing data, which are commonly normalized to remove technical variability. Here, we demonstrate that certain normalization methods, in particular quantile-based methods, can introduce false-positive associations between genes, and that this can consequently hamper downstream co-expression network analysis. Quantile-based normalization can, however, be extremely powerful. In particular when preprocessing large-scale heterogeneous data, quantile-based normalization methods such as smooth quantile normalization can be applied to remove technical variability while maintaining global differences in expression for samples with different biological attributes. We therefore developed SNAIL, a normalization method based on smooth quantile normalization specifically designed for modeling of co-expression measurements. We show that SNAIL avoids formation of false-positive associations in co-expression as well as in downstream network analyses. Using SNAIL, one can avoid arbitrary gene filtering and retain associations to genes that only express in small subgroups of samples. This highlights the method’s potential future impact on network modeling and other association-based approaches in large-scale heterogeneous data.
Genome-wide identification of Arabidopsis non-AUG-initiated upstream ORFs with evolutionarily conserved regulatory sequences that control protein expression levels
Authors: Hiragori Yuta , Takahashi Hiro , Hayashi Noriya , Sasaki Shun , Nakao Kodai , Motomura Taichiro , Yamashita Yui , Naito Satoshi , Onouchi Hitoshi
Published: March 2021

Upstream open reading frames (uORFs) are short ORFs found in the 5′-UTRs of many eukaryotic transcripts and can influence the translation of protein-coding main ORFs (mORFs). Recent genome-wide ribosome profiling studies have revealed that thousands of uORFs initiate translation at non-AUG start codons. However, the physiological significance of these non-AUG uORFs has so far been demonstrated for only a few of them. It is conceivable that physiologically important non-AUG uORFs are evolutionarily conserved across species. In this study, using a combination of bioinformatics and experimental approaches, we searched the Arabidopsis genome for non-AUG-initiated uORFs with conserved sequences that control the expression of the mORF-encoded proteins. As a result, we identified four novel regulatory non-AUG uORFs. Among these, two exerted repressive effects on mORF expression in an amino acid sequence-dependent manner. These two non-AUG uORFs are likely to encode regulatory peptides that cause ribosome stalling, thereby enhancing their repressive effects. In contrast, one of the identified regulatory non-AUG uORFs promoted mORF expression by alleviating the inhibitory effect of a downstream AUG-initiated uORF. These findings provide insights into the mechanisms that enable non-AUG uORFs to play regulatory roles despite their low translation initiation efficiencies.
Neural activity during story listening is synchronized across individuals despite acoustic masking
Authors: Irsik Vanessa C. , Johnsrude Ingrid S. , Herrmann Björn
Published: March 2021

Older people with hearing problems often experience difficulties understanding speech in the presence of background sound. As a result, they may disengage in social situations, which has been associated with negative psychosocial health outcomes. Measuring listening (dis-)engagement during challenging listening situations has received little attention thus far. We recruit young, normal-hearing human adults (both sexes) and investigate how speech intelligibility and engagement during naturalistic story listening is affected by the level of acoustic masking (12-talker babble) at different signal-to-noise ratios (SNRs). In Experiment 1, we observed that word-report scores were above 80% for all but the lowest SNR (-3 dB SNR) we tested, at which performance dropped to 54%. In Experiment 2, we calculated inter-subject correlation (ISC) using electroencephalography (EEG) data to identify dynamic spatial patterns of shared neural activity evoked by the stories. ISC has previously been used as a neural measure of participants’ engagement with naturalistic materials. Our results show that ISC was stable across all but the lowest SNRs, despite reduced speech intelligibility. Comparing ISC and intelligibility demonstrated that word-report performance declined more strongly with decreasing SNR compared to ISC. Our measure of neural engagement suggests that individuals remain engaged in story listening despite missing words due to background noise. Our work provides a potentially fruitful approach to investigate listener engagement with naturalistic, spoken stories that may be used to investigate (dis)engagement in older adults with hearing impairment.
INPP4B drives lysosome biogenesis to restrict leukemic stem cell differentiation and promote leukemogenesis
Authors: Woolley John F. , Chen Keyue , Saffi Golam T. , Genc Gizem E. , Lee Daniel K.C. , Dzneladze Irakli , He Ruijuan , Chow Jonathan T.S. , Gabra Martino M. , Hi Son Meong , Melo Ché M.P. , Newell Candaice A. , He Aobo , Schoof Erwin M. , Xie Stephanie Z. , Mangialardi Emily M. , Kotlyar Max , Rashid Ayesha , Gams Miki. S. , Vacher Jean , Guidos Cynthia J. , Jurisica Igor , Dick John E. , Botelho Roberto J. , Minden Mark D. , Salmena Leonardo
Published: March 2021

Signaling pathways that control vital features of leukemic stem cells including multipotency, self-renewal, clonal expansion and quiescence remain unclear. Emerging studies illustrate critical roles for lysosomes in hematopoietic and leukemic stem cell fate. By investigating consequences ofINPP4Balterations in AML, we have discovered its role in driving leukemic ‘stemness’. We observed thatINPP4Bis highly expressed leukemic stem cell populations andInpp4b-deficeint leukemias demonstrate increased disease latency, reduced leukemia initiating potential which is associated with a differentiated leukemic phenotype. Molecular analyses show thatInpp4b-deficient leukemias have compromised lysosomal gene expression, lysosomal content, and lysosomal activity. Our discovery of a novel pathway linking INPP4B, lysosomal biogenesis and leukemic stemness, provides a mechanism to explain the association of highINPP4Bexpression with poor AML prognosis, and highlights novel patient stratification strategies and LSC-specific leukemic therapies.

Key Points

Our findings highlight a novel pathway linking INPP4B, lysosomal function and leukemic stemness that explains the prognostic role of INPP4B in AML.

Our data reveal the utility of INPP4B as a biomarker of aggressive AML and provide a rationale to explore INPP4B and its associated function in lysosome biology as novel strategies to target LSC and AML
DNA methylation and demethylation underlie the sex difference in estrogen receptor alpha in the arcuate nucleus
Authors: Cortes Laura R. , Cisternas Carla D. , Cabahug Iagn N.K.V. , Mason Damian , Ramlall Emma K. , Castillo-Ruiz Alexandra , Forger Nancy G.
Published: March 2021

Introduction

Neurons expressing estrogen receptor (ER) α in the arcuate nucleus (ARC) of the hypothalamus sex-specifically control energy homeostasis and bone density. Females have more of these neurons than do males, but how this sex difference develops is unknown.

Objective

We tested the hypothesis that DNA methylation and/or demethylation control the development of a sex difference in ERα in the ARC.

Methods

ERα immunoreactive neurons were quantified at birth and at weaning in male, female and testosterone-treated female mice that received neonatal, intracerebroventricular injections of vehicle or zebularine, a DNA methyltransferase inhibitor. Methylation status ofEsr1was determined in the ARC and ventromedial hypothalamus (VMH) using bisulfite conversion of DNA followed by pyrosequencing. Small interfering RNAs against ten-eleven translocases were used to examine effects of demethylation on ERα cell number.

Results

A sex difference in ERα cell number in the ARC, favoring females, developed between birth and weaning and was due to programming effects of testosterone. Zebularine treatment eliminated the sex difference in ERα in the ARC at weaning bydecreasingERαin femalesto male-like levels. Previously, the same treatmentincreasedERαin malesin the VMH. A promoter region ofEsr1exhibited sex differences in opposite directions in percent of total methylation in the ARC (females > males) and VMH (males > females). Moreover, neonatal inhibition of demethylation increased ERα in the ARC of males.

Conclusion

DNA methylation and demethylation regulate ERα cell number in the ARC, and methyl marks may paradoxically activateEsr1in this region.
Neural speech tracking shifts from the syllabic to the modulation rate of speech as intelligibility decreases
Authors: Schmidt Fabian , Chen Ya-Ping , Keitel Anne , Rösch Sebastian , Hannemann Ronny , Serman Maja , Hauswald Anne , Weisz Nathan
Published: March 2021

The most prominent acoustic features in speech are intensity modulations, represented by the amplitude envelope of speech. Synchronization of neural activity with these modulations is vital for speech comprehension. As the acoustic modulation of speech is related to the production of syllables, investigations of neural speech tracking rarely distinguish between lower-level acoustic (envelope modulation) and higher-level linguistic (syllable rate) information. Here we manipulated speech intelligibility using noise-vocoded speech and investigated the spectral dynamics of neural speech processing, across two studies at cortical and subcortical levels of the auditory hierarchy, using magnetoencephalography. Overall, cortical regions mostly track the syllable rate, whereas subcortical regions track the acoustic envelope. Furthermore, with less intelligible speech, tracking of the modulation rate becomes more dominant. Our study highlights the importance of distinguishing between envelope modulation and syllable rate and provides novel possibilities to better understand differences between auditory processing and speech/language processing disorders.

Abstract Figure
A multitask transfer learning framework for novel virus-human protein interactions
Authors: Dong Ngan Thi , Khosla Megha
Published: March 2021

Abstract

Understanding the interaction patterns between a particular virus and human proteins plays a crucial role in unveiling the underlying mechanism of viral infection. This could further help in developing treatments of viral diseases. The main issues in tackling it as a machine learning problem is the scarcity of training data as well input information of the viral proteins. We overcome these limitations by exploiting powerful statistical protein representations derived from a corpus of around 24 Million protein sequences in a multi task framework. Our experiments on 7 varied benchmark datasets support the superiority of our approach.
A covariation analysis reveals elements of selectivity in quorum sensing systems
Authors: Wellington Miranda S , Cong Q , Schaefer AL , MacLeod EK , Zimenko A , Baker D , Greenberg EP
Published: March 2021

Many bacteria communicate with kin and coordinate group behaviors through a form of cell-cell signaling called acyl-homoserine lactone (AHL) quorum sensing (QS). In these systems, a signal synthase produces an AHL to which its paired receptor selectively responds. Selectivity is fundamental to cell signaling. Despite its importance, it has been challenging to determine how this selectivity is achieved and how AHL QS systems evolve and diversify. We hypothesized that we could use covariation within the protein sequences of AHL synthases and receptors to identify selectivity residues. We began by identifying about 6,000 unique synthase-receptor pairs. We then used the protein sequences of these pairs to identify covariation patterns and mapped the patterns onto the LasI/R system fromPseudomonas aeruginosaPAO1. The covarying residues in both proteins cluster around the ligand binding sites. We demonstrate that these residues are involved in system selectivity toward the cognate signal and go on to engineer the Las system to both produce and respond to an alternate AHL signal. We have thus demonstrated a new application for covariation methods and have deepened our understanding of how communication systems evolve and diversify.
Synaptic signaling networks encode experience by assuming stimulus-specific and brain-region-specific states
Authors: Lautz Jonathan D. , Tsegay Kaleb B. , Zhu Zhiyi , Gniffke Edward P. , Welsh John P. , Smith Stephen E.P.
Published: March 2021

A core network of ubiquitously expressed glutamate-synapse-associated proteins mediates activity-dependent synaptic plasticity throughout the brain, but the specific proteomic composition of synapses differs between brain regions. Here, we sought to classify the diversity of activity-dependent remodeling across brain regions using quantitative protein interaction network (PIN) analysis. We first compared the response of cultured neurons to distinct stimuli, and defined PIN parameters that differentiate input types. We next compared the response of three different brain regions maintained alive in vitro to an identical stimulus, and identified three qualitatively different PIN responses. Finally, we measured the PIN response following associative learning tasks, delay and trace eyeblink conditioning, in three brain regions, and found that the two forms of associative learning are distinguished from each other using brain-region-specific network mechanisms. We conclude that although the PIN of the glutamatergic post-synapse is expressed ubiquitously, its activity-dependent dynamics show remarkable stimulus-specific and brain-region-specific diversity.
Characterization of a glycolipid glycosyltransferase with broad substrate specificity from the marine bacteriumCandidatusPelagibacter sp. HTCC7211
Authors: Wei Tao , Zhao Caimeng , Quareshy Mussa , Wu Nan , Huang Shen , Zhao Yuezhe , Yang Pengfei , Mao Duobin , Chen Yin
Published: March 2021

In the marine environment, phosphorus availability significantly affects the lipid composition in many cosmopolitan marine heterotrophic bacteria, including members of the SAR11 clade and the Roseobacter clade. Under phosphorus stress conditions, non-phosphorus sugar-containing glycoglycerolipids are substitutes for phospholipids in these bacteria. Although these glycoglycerolipids play an important role as surrogates for phospholipids under phosphate deprivation, glycoglycerolipid synthases in marine microbes are poorly studied. In the present study, we biochemically characterized a glycolipid glycosyltransferase (GTcp) from the marine bacteriumCandidatusPelagibacter sp. HTCC7211, a member of the SAR11 clade. Our results showed that GTcpis able to act as a multifunctional enzyme by synthesizing different glycoglycerolipids with UDP-glucose, UDP-galactose, or UDP-glucuronic acid as sugar donors and diacylglycerol as the acceptor. Analyses of enzyme kinetic parameters demonstrated that Mg2+notably changes the enzyme’s affinity for UDP-glucose, which improves its catalytic efficiency. Homology modelling and mutational analyses revealed binding sites for the sugar donor and the diacylglycerol lipid acceptor, which provided insights into the retaining mechanism of GTcpwith its GT-B fold. A phylogenetic analysis showed that GTcpand its homologs form a group in the GT4 glycosyltransferase family. These results not only provide new insights into the glycoglycerolipid synthesis mechanism in lipid remodelling, but also describe an efficient enzymatic tool for future synthesis of bioactive molecules.

Importance

The bilayer formed by membrane lipids serves as the containment unit for living microbial cells. In the marine environment, it has been firmly established that phytoplankton and heterotrophic bacteria can substitute phospholipids with non-phosphorus sugar-containing glycoglycerolipids in response to phosphorus limitation. However, little is known about how these glycoglycerolipids are synthesized. Here, we determined the biochemical characteristics of a glycolipid glycosyltransferase (GTcp) from the marine bacteriumCandidatusPelagibacter sp. HTCC7211. GTcpand its homologs form a group in the GT4 glycosyltransferase family, and can synthesize neutral glycolipids (MGlc-DAG and MGal-DAG) and an acidic glycolipid (MGlcA-DAG). We also uncover the key residues for DAG-binding through molecular docking, site-direct mutagenesis and subsequent enzyme activity assays. Our data provide new insights into the glycoglycerolipid synthesis mechanism in lipid remodelling.
α2δ-2 is Required for Depolarization-induced Suppression of Excitation in Purkinje cells
Authors: Beeson Kathleen A. , Westbrook Gary L. , Schnell Eric
Published: March 2021

α2δ proteins (CACNA2D1-4) are required for normal neurological function, although how they control neuronal output remains unclear. Using whole-cell recordings of mouse Purkinje cells, we show α2δ-2 is required for functional coupling of postsynaptic voltage-dependent calcium entry with effector mechanisms controlling two different outputs, depolarization-induced suppression of excitation mediated by endocannabinoid signaling, and spike afterhyperpolarization generated by calcium-dependent potassium channels. Our findings indicate an important role for α2δ-2 proteins in regulating functional postsynaptic calcium channel-coupling in neurons.

Significance Statement

Calcium influx via membrane voltage-dependent calcium channels drives numerous neuronal processes by signaling through calcium-dependent effector molecules. Signal precision is achieved in part by calcium channel-effector coupling. In mouse Purkinje cell neurons, we show that neuronal α2δ-2 protein functionally couples calcium entry to two different postsynaptic calcium-dependent signals, retrograde endocannabinoid signaling and the action potential afterhyperpolarization. Our findings provide new insights about the control of calcium channel-effector coupling as well as new roles for α2δ-2 proteins in neurons.
Prospective SARS-CoV-2 cohort study among general practitioners during the second COVID-19 wave in Flanders, Belgium
Authors: Mariën Joachim , Ceulemans Ann , Bakokimi Diana , Lammens Christine , Ieven Margareta , Heytens Stefan , Sutter An De , Verbakel Jan Y , Van den Bruel Ann , Goossens Herman , Van Damme Pierre , Ariën Kevin K. , Coenen Samuel
Published: March 2021

Primary health care providers (PHCPs), especially general practitioners (GPs) are essential to organise health care efficiently. During the COVID-19 pandemic, they also keep the pressure off hospitals. PHCPs are assumed to be at high risk of a COVID-19 infection, as they are exposed to a large portion of the population (usually with less personal protective equipment than other frontline health care workers(HCWs)). Nevertheless, previous seroprevalence studies focussed on the general population or HCWs in hospital settings, rather than PHCPs. The aim of this study was to determine the seroprevalence of PHCPs after the first and during the second SARS-CoV-2 wave in Flanders (Belgium) and compare it to the seroprevalence in the general population (blood donors). A prospective cohort of PHCPs, mainly GPs (n=698) was screened for IgG antibodies against SARS-CoV-2 at five different time-points (June-December 2020). The dried blood spots they produced were analysed using a Luminex multiplex immunoassay. The seroprevalence of PHCPs remained stable between June and September 2020 (4.6-5.0%), but increased significantly from October to December (8.1-13.4%) 2020. The seroprevalence of PHCPs was not significantly higher than the seroprevalence of the blood donors at the end of December 2020. In conclusion, the sharp increase in seroprevalence during the second COVID-19 wave in Flanders shows that PHCPs were more at risk during the second wave compared to the first one. However, the increase was in line with the general population suggesting that PHCPs mainly got infected in their private settings.
On discrete time epidemic models in Kermack-McKendrick form
Authors: Diekmann Odo , Othmer Hans G. , Planque Robert , Bootsma Martin CJ
Published: March 2021

Surprisingly, the discrete-time version of the general 1927 Kermack-McKendrick
epidemic model has, to our knowledge, not been formulated in the literature, and
we rectify this omission here. The discrete time version is as general and
flexible as its continuous-time counterpart, and contains numerous
compartmental models as special cases. In contrast to the continuous time
version, the discrete time version of the model is very easy to implement
computationally, and thus promises to become a powerful tool for exploring
control scenarios for specific infectious diseases. To demonstrate the
potential, we investigate numerically how the incidence-peak size depends on
model ingredients. We find that, with the same reproduction number and initial
speed of epidemic spread, compartmental models systematically predict lower peak
sizes than models that use a fixed duration for the latent and infectious periods.
Molecular roadmap of the healthy stress response in the mouse hippocampus
Authors: von Ziegler Lukas M. , Floriou-Servou Amalia , Waag Rebecca , Das Gupta Rebecca R. , Sturman Oliver , Gapp Katharina , Maat Christina A. , Kockmann Tobias , Lin Han-Yu , Duss Sian N. , Privitera Mattia , Hinte Laura , von Meyenn Ferdinand , Zeilhofer Hanns U. , Germain Pierre-Luc , Bohacek Johannes
Published: March 2021

The acute stress response mobilizes energy to meet situational demands and re-establish homeostasis. However, little is known about the nature and dynamics of the underlying molecular cascades. We used a brief forced swim exposure to trigger a strong stress response in mice, which transiently increases anxiety, but does not lead to lasting maladaptive behavioral changes. Using multiomic profiling we characterize the stress-induced molecular events in the hippocampus over time, across molecular scales, and down to the level of cell types and single cells. Our results unveil the complexity and specificity of the healthy stress response, with widespread changes in protein phosphorylation and gene transcription, but tightly regulated protein translation. All observed molecular events resolve efficiently within 4 hours after initiation of stress. The data are accessible through an interactive web portal, creating an extensive molecular resource that will help understand how stress impacts brain function in health and disease.
Polymorphism of dimethylaminoborane N(CH3)2-BH2
Authors: Bodach Alexander , Bernert Thomas , Fischer Michael , Ley Morten Brix , Weidenthaler Claudia
Published: March 2021

Dehydrocoupling of the adduct of dimethylamine and borane, NH(CH3)2-BH3 leads to dimethylaminoborane with formal composition N(CH3)2-BH2. The structure of this product depends on the conditions of the synthesis; it may crystallize either as a dimer in a triclinic space group forming a four-membered ring [N(CH3)2-BH2]2 or as a trimer forming a six-membered ring [N(CH3)2-BH2]3 in an orthorhombic space group. Due to the denser packing, the six-membered ring in the trimer structure should be energetically more stable than the four-membered ring. The triclinic structure is stable at low temperatures. Heating the triclinic phase above 290 K leads to a second-order phase transition to a new monoclinic polymorph. While the crystal structures of the triclinic and orthorhombic phases were already known in the literature, the monoclinic crystal structure was determined from powder diffraction data in this study. Monoclinic dimethylaminoborane crystallizes in space group C2/m with the boron and nitrogen atoms located on the mirror plane, Wyckoff position 4i, while the carbon and hydrogen atoms are on the general position 8j.
Crystal structure and Hirshfeld surface analysis of trans-2,5-dimethylpiperazine-1,4-diium tetrachloridocobaltate(II)
Authors: Landolsi Meriem , Abid Sonia
Published: March 2021

In the title molecular salt, (C6H16N2)[CoCl4], the complete dication is generated by crystallographic inversion symmetry and the piperazine ring adopts a chair conformation with the pendant methyl groups in equatorial orientations. The complete dianion is generated by crystallographic twofold symmetry. In the crystal, the (C6H16N2)2+ and [CoCl4]2− ions are linked by N—H...Cl and C—H...Cl hydrogen bonds, thereby forming a two-dimensional supramolecular network. The Hirshfeld surface analysis and fingerprint plots reveal that the largest contributions to the crystal stability come from H...Cl/Cl...H (68.4%) and H...H (27.4%) contacts.
A systematic review of machine learning in logistics and supply chain management: current trends and future directions
Authors: Akbari Mohammadreza , Do Thu Nguyen Anh
Published: March 2021

Purpose

This paper presents a review of the existing state-of-the-art literature on machine learning (ML) in logistics and supply chain management (LSCM) by analyzing the current literature, contemporary concepts, data and gaps and suggesting potential topics for future research.

Design/methodology/approach

A systematic/structured literature review in the subject discipline and a bibliometric analysis were organized. Information regarding industry involvement, geographic location, research design and methods, data analysis techniques, university, affiliation, publishers, authors, year of publications is documented. A wide collection of eight databases from 1994 to 2019 were explored using the keywords “Machine Learning” and “Logistics“, “Transportation” and “Supply Chain” in the title and/or abstract. A total of 110 articles were found, and information on a chain of variables was gathered.

Findings

Over the last few decades, the application of emerging technologies has attracted significant interest all around the world. Analysis of the collected data shows that only nine literature reviews have been published in this area. Further, key findings show that 53.8 per cent of publications were closely clustered on transportation and manufacturing industries and 54.7 per cent were centred on mathematical models and simulations. Neural network is applied in 22 papers as their exclusive algorithms. Finally, the main focuses of the current literature are on prediction and optimization, where detection is contributed by only seven articles.

Research limitations/implications

This review is limited to examining only academic sources available from Scopus, Elsevier, Web of Science, Emerald, JSTOR, SAGE, Springer, Taylor and Francis and Wiley which contain the words “Machine Learning” and “Logistics“, “Transportation” and “Supply Chain” in the title and/or abstract.

Originality/value

This paper provides a systematic insight into research trends in ML in both logistics and the supply chain.
Opportunities and constraints of women entrepreneurs in Jordan: an update of the 5Ms framework
Authors: Abuhussein Tala , Koburtay Tamer
Published: March 2021

Purpose

Drawing on the “5Ms” gender cognizant framework, this study seeks to investigate how money, motherhood, management, the market and the macro/meso environment dimensions of the 5Ms may influence women's entrepreneurship in Jordan. A related aim is to offer in-depth insights and a fresh understanding of potential factors not included in the original 5Ms model.

Design/methodology/approach

The study takes a qualitative-inductive approach, using semi-structured interviews with 14 women entrepreneurs from various industries in Jordan.

Findings

The paper highlights the positive (or adverse) impact of the 5Ms factors (motherhood, macro/meso environment, the market, management and money) on women entrepreneurs in Jordan and introduces new emerging factors. The paper concludes with an extended view of the 5Ms model.

Practical implications

This study may help develop greater sensitivity and understanding about some of the adverse gender practices faced by women entrepreneurs. Policymakers in Jordan and other Arab countries may consider empowering women entrepreneurs in terms of offering more financial funds and facilities, social support, and managerial empowerment.

Originality/value

The study creates more sensitivity and awareness about the current dynamics, opportunities and impediments that affect women entrepreneurs; thus, it contributes to the extant literature by suggesting new propositions and a novel framework. This study extends Brush et al.'s (2009) 5Ms gendered framework by adding three important factors (Mental health, Maturity and Maintainability). The empirical update and contextual extension of Brush et al.'s (2009) 5Ms model highlight a theoretical contribution.
The impact of spiritual values on employees loyalty: the moderating role of Islamic work ethic
Authors: Ahmed Adeel , Arshad Mohd Anuar , Mahmood Arshad , Barkat Waseem
Published: March 2021

Purpose

The purpose of this study is to examine the impact of spiritual values (i.e. sense of community, sense of meaning and wisdom) on employee loyalty. Spiritual values are widely accepted by scholars and practitioners as a fundamental element for employee performance. This study explored and enriched the body of knowledge on spiritual and Islamic values, as it investigated the interactive effect of Islamic work ethic (IWE). The theoretical foundation of this research is based on social exchange theory.

Design/methodology/approach

A cross-sectional design with purposive sampling was used to collect data from the airline industry. A partial least square (PLS) second-generation structural equation modeling method (Smart-PLS software) was used to test the hypothesized relationship.

Findings

The study findings revealed that giving importance to spiritual values could add value to the performance of the organization. In addition, based on study findings, organizations should give high priority to Islamic orientations at work and promote IWEs in the true sense.

Research limitations/implications

The scope of the study is one of the limitations. This study was unable to get a random sample due to the unavailability of a comprehensive and complete list of employees. In addition, from a methodological point of view, this research relied on a single source, which is subjected to bias. Future studies should replicate and test the applicability of the current framework in any other global context.

Originality/value

To the best of the author’s knowledge, no studies in past tested these relationships, which is a contribution to the literature. This research should be an avenue for further inquiries using more rigorous approaches.
Identification and analysis of circular supply chain management practices for sustainability: a fuzzy-DEMATEL approach
Authors: Saroha Manju , Garg Dixit , Luthra Sunil
Published: March 2021

Purpose

Circular supply chain management (CSCM) is proving to be a strong contributor towards sustainable development. The purpose of this study is to analyse the circular practices in CSCM implementation towards sustainability in the Indian auto sector; these practices are at the initial stage in a developing economy.

Design/methodology/approach

In this research work, a framework has been developed to enrich understanding of various CSCM practices for sustainability. To develop a causal framework, a Fuzzy Decision-Making Trial and Evaluation Laboratory (F-DEMATEL) methodology has been adopted.

Findings

The results produce 32 practices with cause and effect groups and their importance/priorities. Based on F-DEMATEL, these 32 practices are grouped into cause and effect groups based on R + C and R − C values.

Research limitations/implications

The findings will help managers and decision-makers to gain a deeper understanding of the practices and their nature; the governmental and financial practices are identified as the most critical factors that need more attention. The results will help strategy makers to plan accordingly.

Originality/value

This research has identified and analysed 32 basic practices and their interrelationships to achieve sustainability in CSCM.
Information technology management and service performance management capabilities: an empirical study of the service supply chain management process
Authors: Lenuwat Pattama , Boon-itt Sakun
Published: March 2021

Purpose

The dynamic capabilities view is invoked to hypothesize relationships among the service supply chain management (SSCM) process capabilities using the information technology management (ITM) process capability. This study argues that ITM will have an impact on the service performance management (SPM) process capability only when it works through mediators and demonstrates the impact by using the framework of SSCM process capabilities.

Design/methodology/approach

This study is based on a survey using quantitative data collection to empirically test the research framework. The proposed framework and hypotheses were tested using a mail-in survey of the service industry in Thailand. The statistical analysis of data acquired from the survey was performed using structural equation modeling.

Findings

The results support the existence of a mediating role for the ITM process affecting the SPM process. This study identifies the role of ITM and emphasizes the urgent need for firms to embed other mediating factors into their approaches to achieve SPM process goals in the service supply chain context.

Research limitations/implications

The study offers important implications to researchers as well as practitioners by highlighting the significance of mediating roles for ITM to achieve SPM process.

Originality/value

This research is among the initial attempts to argue the impact of ITM on SPM through mediators.
Governance and accountability in hybrid organizations – past, present and future
Authors: Vakkuri Jarmo , Johanson Jan-Erik , Feng Nancy Chun , Giordano Filippo
Published: March 2021

Purpose

In addressing policy problems, it is difficult to disentangle public policies from private efforts, business institutions and civic activities. Societies may acknowledge that all these domains have a role in accomplishing social aims, but there are fundamental problems in understanding why, how and with what implications this occurs. Drawing upon the insights from the papers of this special issue, the authors aim to advance the understanding of governance and accountability in different contexts of hybridity, hybrid governance and organizations.

Design/methodology/approach

The authors conceptualize common theoretical origins of hybrid organizations and the ways in which they create and enact value by reflecting on the articles of the special issue. Furthermore, the authors propose agendas for future research into hybrid organizations.

Findings

Hybrid organizations can be conceptualized through two types of lenses: (1) the dimensions of hybridity (ownership, institutional logics, funding and control) and (2) their approaches to value creation (mixing, compromising and legitimizing).

Practical implications

This article provides more detailed and comprehensive understanding of hybridity. This contribution has also important practical implications for actors, such as politicians, managers, street-level bureaucrats, professionals, auditors and accountants who may be enveloped in various hybrid settings, policy contexts and multi-faceted interfaces between public, private and the civil society sector.

Originality/value

Hybridity lenses reveal novel connections between four types of hybrid institutional contexts: state-owned enterprises (SOEs), non-profit organizations (NPOs), social enterprises (SEs) and municipally owned corporations (MOCs). This paper provides theoretical instruments for doing so.
Sustainability measures and earnings management: evidence from Greek municipalities
Authors: Cohen Sandra , Malkogianni Ioanna
Published: March 2021

Purpose

This study analyses the engagement of Greek municipalities in earnings management activities through the manipulation of their accrual accounts. It aims at identifying whether discretionary accruals are associated with certain financial sustainability measures calculated through financial statement numbers.

Design/methodology/approach

To test the hypotheses, the annual financial data of Greek municipalities for the period 2011–2018 are used. The final sample corresponds to an unbalanced panel data sample that includes 1,565 yearly observations. Total accruals and discretionary accruals modelling are based both on the aggregate Jones model and the modified Jones model.

Findings

The findings provide evidence that Greek municipalities engage in earnings management practices through the manipulation of accruals. Moreover, there is corroborative evidence that financial sustainability indicators, such as indebtedness, liquidity and efficiency ratios, are related to the magnitude of earnings management, while earnings management behaviour during the year preceding the municipal elections is more intense.

Originality/value

The paper expands the literature in earnings management in local governments by analysing the relation of financial sustainability indicators to this behaviour.
The threat of bankruptcy and financing strategy in learning-intensive industries
Authors: Deb Palash , Sreekumar Vipin
Published: March 2021

Purpose

The authors investigate whether firms in learning-intensive industries are more prone to bankruptcy and how this shapes a firm's financing choices.

Design/methodology/approach

Industry learning estimates based on US manufacturing firms are obtained from the study of Balasubramanian and Lieberman (2010; 2011), who collected these estimates from the US Census Bureau. Merging the learning estimates with data from Compustat gives us a final sample of 6,138 publicly-traded US manufacturing ﬁrms (56,930 ﬁrm-years) between 1973 and 2000. The authors use both OLS and IV estimation approaches to test the hypotheses.

Findings

The findings confirm that firms operating in learning-intensive industries have a higher threat of bankruptcy. The authors also find that a debt-intensive capital structure exacerbates the threat of bankruptcy; therefore, firms in such industries have a significantly lower reliance on debt financing.

Practical implications

In the current turbulent business environment, managers operating in learning-intensive industries need to be more careful while making financing choices between debt and equity, and they can explore sources of financing that go beyond the capital markets.

Originality/value

No study so far has examined how industry learning intensity, a key industry characteristic, makes firms more prone to bankruptcy, and how this threat of bankruptcy results in more conservative financing choices. By integrating the theoretical perspectives from the structure–conduct–performance (SCP), transaction cost economics (TCE) and threat rigidity paradigms, this paper contributes to the literature by adding the industry learning environment as a novel determinant of firm financing choices and the threat of bankruptcy.