bluuebunny/crossref_metadata_2025 huggingface dataset:
Early maternal loss affects diurnal cortisol slopes in immature but not mature wild chimpanzees
Authors: Girard-Buttoz Cédric , Tkaczynski Patrick J. , Samuni Liran , Fedurek Pawel , Gomes Cristina , Löhrich Therese , Manin Virgile , Preis Anna , Valé Prince , Deschner Tobias , Wittig Roman M. , Crockford Catherine
Published: October 2020

In mammals, early life adversity negatively affects survival and reproductive success. A key causal mechanism is proposed by the biological embedding model which posits that adversity experienced early in life has deleterious consequences on individual physiology across the lifespan. In particular, early life adversity is expected to be a severe stressor leading to long-term alteration of the hypothalamic pituitary adrenal (HPA) axis activity. Here we tested this idea by assessing whether, as in humans, maternal loss had short and long-term impacts on orphan chimpanzee urinary cortisol levels and diurnal urinary cortisol slopes, as an indicator of the HPA axis functioning. We used 18 years of data on 50 immature and 28 mature male wild chimpanzees belonging to four communities in Taï National Park, Ivory Coast. Immature orphans who experienced early maternal loss had diurnal cortisol slopes characterised by higher early morning and late afternoon cortisol levels indicative of high activation of the HPA axis. Recently orphaned immatures had higher cortisol levels than other immatures, possibly reflecting social and nutritional stress. However, unlike in humans, we did not find significantly different cortisol profiles in orphan and non-orphan adult male chimpanzees. Our study highlights that long-term alteration of stress physiology related to early life adversity may not be viable in some wild animal populations and/or that chimpanzees, as humans, may have access to mechanisms that buffer this physiological stress, such as adoption. Our results suggest that biological embedding of altered HPA axis function is unlikely to be a mechanism contributing to the demonstrated long-term fitness consequences of maternal loss, such as reduced reproductive success, in wild long-lived mammals.
Multiple decisions about one object involve parallel sensory acquisition but time-multiplexed evidence incorporation
Authors: Kang Yul HR , Löffler Anne , Jeurissen Danique , Zylberberg Ariel , Wolpert Daniel M , Shadlen Michael N
Published: October 2020

The brain is capable of processing several streams of information that bear on different aspects of the same problem. Here we address the problem of making two decisions about one object, by studying difficult perceptual decisions about the color and motion of a dynamic random dot display. We find that the accuracy of one decision is unaffected by the difficulty of the other decision. However, the response times reveal that the two decisions do not form simultaneously. We show that both stimulus dimensions are acquired in parallel for the initial ~0.1 s but are then incorporated serially in time-multiplexed bouts. Thus there is a bottleneck that precludes updating more than one decision at a time, and a buffer that stores samples of evidence while access to the decision is blocked. We suggest that this bottleneck is responsible for the long timescales of many cognitive operations framed as decisions.
iTRAQ-Based Proteomic Profiling of PLC-Mediated Expression of 20E-Induced Protein inApolygus lucorum(Meyer-Dür)
Authors: Tan Yong-An , Zhao Xu-Dong , Zhao Jing , Ji Qin-Qin , Xiao Liu-Bin , Hao De-Jun
Published: October 2020

The polyphagous pestApolygus lucorumhas become the dominant insect inBacillus thuringiensis(Bt) cotton fields. The hormone 20-hydroxyecdysone (20E) regulates multiple events in insect development and physiology. 20E responses are controlled by pathways triggered by phospholipase C (PLC)-associated proteins. However, 20E-modulated genes whose expression is affected by PLC remain unknown. Here, isobaric tag for relative and absolute quantitation (iTRAQ) and immunoblot were carried out for comparing differentially expressed proteins (DEPs) inA. lucorumin response to 20E and the PLC inhibitor U73122, respectively. Totally 1624 DEPs were, respectively, found in the 20E/control, U73122/control, and 20E+U73122/control groups. Venn diagram analysis further revealed 8 DEPs that were shared among the three groups. Immunoblot validated these findings, which corroborated and highlighted the reliability of proteomics. KEGG enrichment analysis showed that the DEPs were included in diverse signaling pathways. The largest portion of DEPs among the three groups were categorized in metabolic pathways. In addition, DEPs among the three groups were also found to regulate the Ras-MAPK and PI3K-AKT pathways. This is the first time that iTRAQ was carried out to assess proteome alteration inA. lucorumnymphs in response to 20E and a PLC inhibitor. These findings provide novel insights into protein expression inA. lucorumin response to 20E, and a more comprehensive understanding of the function of PLC in 20E signal transduction.
Synaptic diversity naturally arises from neural decoding of heterogeneous populations
Authors: Yates Jacob L. , Scholl Benjamin
Published: October 2020

The synaptic inputs to single cortical neurons exhibit substantial diversity in their sensory-driven activity. What this diversity reflects is unclear, and appears counter-productive in generating selective somatic responses to specific stimuli. We propose that synaptic diversity arises because neurons decode information from upstream populations. Focusing on a single sensory variable, orientation, we construct a probabilistic decoder that estimates the stimulus orientation from the responses of a realistic, hypothetical input population of neurons. We provide a straightforward mapping from the decoder weights to real excitatory synapses, and find that optimal decoding requires diverse input weights. Analytically derived weights exhibit diversity whenever upstream input populations consist of noisy, correlated, and heterogeneous neurons, as is typically foundin vivo. In fact, in silico weight diversity was necessary to accurately decode orientation and matched the functional heterogeneity of dendritic spines imaged in vivo. Our results indicate that synaptic diversity is a necessary component of information transmission and reframes studies of connectivity through the lens of probabilistic population codes. These results suggest that the mapping from synaptic inputs to somatic selectivity may not be directly interpretable without considering input covariance and highlights the importance of population codes in pursuit of the cortical connectome.
The Effects of Inter-Individual Biological Differences and Taphonomic Alteration on Human Bone Protein Profiles: Implications for the Development of PMI/AAD Estimation Methods
Authors: Mickleburgh Hayley L. , Schwalbe Ed , Mizukami Haruka , Sellitto Federica , Starace Sefora , Wescott Daniel J. , Carter David O. , Procopio Noemi
Published: October 2020

Bone proteomics studies using animal proxies and skeletonized human remains have delivered encouraging results in the search for potential biomarkers for precise and accurate post-mortem interval (PMI) and the age-at-death (AAD) estimation in medico-legal investigations. At present, however, the effects of inter-individual biological differences and taphonomic alteration on recovered human bone protein profiles are not well understood. This study investigated the human bone proteome in four human body donors studied throughout decomposition outdoors. The effects of ageing phenomena (in vivoand post-mortem), and intrinsic and extrinsic variables on the variety and abundancy of the bone proteome were assessed. Results identified a new potential biomarker for PMI estimation, as well as three potential biomarkers for AAD estimation. The results also suggest that bone mineral density (BMD) may be an important variable affecting the survival and extraction of proteins.

Highlights

- CO3, CO9, COBA2, CO3A1, MGP, PGS2 and TTHY are potential biomarkers for post-mortem interval estimation in skeletonized human remains

- FETUA, ALBU and OLFL3 are potential biomarkers for age-at-death estimation in human remains

- Taphonomic and biological variables play a significant role in survival and extraction rates of proteins in bone

- Bone mineral density may affect survival of proteins in bone, probably due to the effects of the mineral matrix on the movement of decomposer microbes

- Higher bone mineral density may affect the survival and the extraction rate of collagen and mineral-binding proteins
In vitro Antibacterial effect ofCommiphora myrrhaOil against Dental Pathogens
Authors: Izzeldien Reem , Abdulaziz Sondos , Ahmed Ayat , Noma Mounkaila
Published: October 2020

Dental caries is a chronic disease caused by the interaction of oral microorganisms, diet and host factors over time.Streptococcus mutansis considered as the main bacteria involve in dental decay, while the level ofLactobacillus spp. is directly related to the presence or onset of caries.Commiphora myrrhais an ancient plant which extracts are used as antiseptic and anti-inflammatory for mouth and throat due to it is antimicrobial activity. This study assessed the impact ofCommiphora myrrhaon two bacteriaStreptococcus mutansandLactobacillus spp. involved in dental caries. Three samples ofStreptococcus mutansbacteria were collected randomly from patients with dental caries in Khartoum dental teaching hospital, whileLactobacillus spp. were obtained from fermented milk. Disk and well diffusion methods were used to test the effect of four concentration (100,50,25 and 12.5 mg/ml) of Myrrha volatile oil, extracted by hydro-distillation technique. The biochemical analysis ofCommiphora myrrhaoil was carried out using Gas Chromatography/Mass Spectrophotometric technique. The finding revealed that the four concentrations of oil were effective onStreptococcus mutanswith the largest inhibition zone (18.7± 0.6 mm) through the well diffusion method and inhibition zone of (14.00 mm) with disc diffusion method regardless the two methods these inhibition zones were recorded at 100 mg/ml, with Minimum Bactericidal Concentration (MBC) at 3.125 mg/ml. WhileLactobacillus spp. bacteria sensitive to three concentrations (100,50 and 25 mg/ml) and resistance to concentration 12.5 mg/ml, it is MBC found to be 25 mg/ml. In conclusion, this research revealed that Myrrh oil is effective on bothS.mutansandLactobacillus spp. Hence, Myrrha oil is a potential antibacterial product of interest in dental caries.
Coupling of H3K27me3 recognition with transcriptional repression through the BAH-PHD-CPL2 complex inArabidopsis
Authors: Zhang Yi-Zhe , Yuan Jianlong , Zhang Lingrui , Chen Chunxiang , Wang Yuhua , Zhang Guiping , Peng Li , Xie Si-Si , Jiang Jing , Zhu Jian-Kang , Du Jiamu , Duan Cheng-Guo
Published: October 2020

Histone 3 Lys 27 trimethylation (H3K27me3)-mediated epigenetic silencing plays a critical role in multiple biological processes. However, the H3K27me3 recognition and transcriptional repression mechanisms are only partially understood. Here, we report a new mechanism for H3K27me3 recognition and transcriptional repression. Our structural and biochemical data showed that the BAH domain protein AIPP3 and the PHD proteins AIPP2 and PAIPP2 cooperate to read H3K27me3 and unmodified H3K4 histone marks, respectively, inArabidopsis. The BAH-PHD bivalent histone reader complex silences a substantial subset of H3K27me3-enriched loci, including a number of development and stress response-related genes such as the RNA silencing effector geneARGONAUTE 5(AGO5) and We found that the BAH-PHD module associates with CPL2, a plant-specific Pol II carboxyl terminal domain (CTD) phosphatase, to form the BAH-PHD-CPL2 complex (BPC) for transcriptional repression. The BPC complex represses transcription through CPL2-mediated CTD dephosphorylation, thereby causing inhibition of Pol II release from the transcriptional start site. Our work reveals a mechanism coupling H3K27me3 recognition with transcriptional repression through the alteration of Pol II phosphorylation states, thereby contributing to our understanding of the mechanism of H3K27me3-dependent silencing.
Assessment of Heterogeneity of Cytochrome P450 Activity in Cancer-Cell Population by Cytometry of Reaction Rate Constant is Robust to Variation in Substrate Concentration
Authors: Oliveira Mariana Bleker de , Koshkin Vasilij , Perry Christopher G. R. , Krylov Sergey N.
Published: October 2020

Enzymes of the cytochrome P450 (CYP) family catalyze the metabolism of chemotherapeutic agents and are among the key players in primary and acquired chemoresistance of cancer. The activity of CYP is heterogeneous in tumor tissues, and the quantitative characteristics of this heterogeneity can be used to predict chemoresistance. Cytometry of reaction rate constant (CRRC) is a kinetic approach to assess cell population heterogeneity by measuring rates of processes at the single-cell levelviatime-lapse imaging. CRRC was shown to be an accurate and robust method for assessing the heterogeneity of drug-extrusion activity catalyzed by ABC transporters, which are also key players in cancer chemoresistance. We hypothesized that CRRC is also a reliable method for assessing the heterogeneity of CYP activity. Here, we evaluated the robustness of assessing the heterogeneity of CYP activity by CRRC with respect to controlled variation in the concentration of a CYP substrate by comparing CRRC with non-kinetic approaches. We found that changing the substrate concentration by 20% resulted only in minimal changes in the position, width, and asymmetry of the peak in the CRRC histogram, while these parameters varied greatly in the non-kinetic histograms. Moreover, the Kolmogorov-Smirnov statistical test showed that the distribution of the cell population in CRRC histograms was not significantly different; the result was opposite for non-kinetic histograms. In conclusion, we were able to demonstrate the robustness of CRRC with respect to changes in substrate concentration when evaluating CYP activity at the single-cell level.
Extinctions have strongly reduced the mammalian consumption of primary productivity
Authors: Pedersen Rasmus Østergaard , Faurby Søren , Svenning Jens-Christian
Published: October 2020

Herbivorous mammals are important for natural ecosystems even today, but how much stronger would there effects be without human-linked extinctions and extirpations? The ranges of many mammal species have contracted and numerous species have gone extinct due to human pressures, so herbivore impacts in even seemingly natural ecosystems likely deviate from their pre-anthropogenic state. However, such effects remain poorly understood and often unrecognized. To address this issue, we here quantified and mapped plant consumption by all terrestrial mammals in natural areas based on both current and estimated natural ranges. We then compared the estimated consumption rates to current plant net primary productivity, and summarised the results for global ecosystem types both broadly and in the wildest remaining natural areas around the world (the Last of the Wild). We found that wild mammals consume 7.3% (95% interquantile range: 0.85% - 26%) of net primary productivity in current natural areas, and that this would be much higher in the absence of extinctions and extirpations, namely 13% (95% interquantile range: 1.7% - 40%), i.e., a >50% higher consumption rate. Marked human-linked declines in herbivory were seen even in the wildest remaining natural areas, where mammals now consume a mean of 9% (95% interquantile range: 2.2% - 26%) of plant primary productivity, which is only 60% of no-extinction level. Our results show that mammalian herbivores naturally play an important part in ecosystems at a global scale, but that this effect has been strongly reduced by extinctions and extirpations.
Clustered Rapid Induction of Apoptosis Limits ZIKV and DENV-2 Proliferation in the Midguts ofAedes aegypti
Authors: Ayers Jasmine B. , Coatsworth Heather G. , Kang Seokyoung , Dinglasan Rhoel R. , Zhou Lei
Published: October 2020

Inter-host transmission of pathogenic arboviruses such as dengue virus (DENV) and Zika virus (ZIKV) requires systemic infection of the mosquito vector. Successful systemic infection requires initial viral entry and proliferation in the midgut cells of the mosquito followed by dissemination to secondary tissues and eventual entry into salivary glands1. Lack of arbovirus proliferation in midgut cells has been observed in severalAedes aegyptistrains2, but the midgut antiviral responses underlying this phenomenon are not yet fully understood. We report here that there is a rapid induction of apoptosis (RIA) in theAedes aegyptimidgut epithelium within 2 hours of infection with DENV-2 or ZIKV in bothin vivoblood-feeding andex vivomidgut infection models. Inhibition of RIA led to increased virus proliferation in the midgut, implicating RIA as an innate immune mechanism mediating midgut infection in this mosquito vector.
Removing independent noise in systems neuroscience data using DeepInterpolation
Authors: Lecoq Jérôme , Oliver Michael , Siegle Joshua H. , Orlova Natalia , Koch Christof
Published: October 2020

Progress in nearly every scientific discipline is hindered by the presence of independent noise in spatiotemporally structured datasets. Three widespread technologies for measuring neural activity—calcium imaging, extracellular electrophysiology, and fMRI—all operate in domains in which shot noise and/or thermal noise deteriorate the quality of measured physiological signals. Current denoising approaches sacrifice spatial and/or temporal resolution to increase the Signal-to-Noise Ratio of weak neuronal events, leading to missed opportunities for scientific discovery.

Here, we introduceDeepInterpolation, a general-purpose denoising algorithm that trains a spatio-temporal nonlinear interpolation model using only noisy samples from the original raw data. Applying DeepInterpolation toin vivotwo-photon Ca2+imaging yields up to 6 times more segmented neuronal segments with a 15 fold increase in single pixel SNR, uncovering network dynamics at the single-trial level. In extracellular electrophysiology recordings, DeepInterpolation recovered 25% more high-quality spiking units compared to a standard data analysis pipeline. On fMRI datasets, DeepInterpolation increased the SNR of individual voxels 1.6-fold. All these improvements were attained without sacrificing spatial or temporal resolution.

DeepInterpolation could well have a similar impact in other domains for which independent noise is present in experimental data.
K29-Linked Ubiquitin Signaling Regulates Proteotoxic Stress Response and Cell Cycle
Authors: Yu Yuanyuan , Zheng Qingyun , Erramilli Satchal K. , Pan Man , Park Seongjin , Xie Yuan , Li Jingxian , Fei Jingyi , Kossiakoff Anthony A. , Liu Lei , Zhao Minglei
Published: October 2020

Protein ubiquitination shows remarkable topological and functional diversity through the polymerization of ubiquitin via different linkages. Deciphering the cellular ubiquitin code is of central importance to understand the physiology of the cell. Among the eight possible linkages, K29-linked polyubiquitin is a relatively abundant type of polyubiquitin in both human and yeast cells. However, our understanding of its function is rather limited due to the lack of specific binders as tools to detect K29-linked polyubiquitin. In this study, we screened and characterized a synthetic antigen-binding fragment, termed sAB-K29, that can specifically recognize K29-linked polyubiquitin using chemically synthesized K29-linked diubiquitin. We further determined the crystal structure of this fragment bound to the K29-linked diubiquitin, which revealed the molecular basis of specificity. Using sAB-K29 as a tool, we uncovered that K29-linked ubiquitination is involved in different kinds of cellular proteotoxic stress response as well as cell cycle regulation. In particular, we showed that K29-linked ubiquitination is enriched in the midbody and downregulation of the K29-linked ubiquitination signal arrests cells in G1/S phase.
Noise correlations for faster and more robust learning
Authors: Nassar Matthew R. , Scott Daniel , Bhandari Apoorva
Published: October 2020

Distributed population codes are ubiquitous in the brain and pose a challenge to downstream neurons that must learn an appropriate readout. Here we explore the possibility that this learning problem is simplified through inductive biases implemented by stimulus-independent noise correlations that constrain learning to task-relevant dimensions. We test this idea in a set of neural networks that learn to perform a perceptual discrimination task. Correlations among similarly tuned units were manipulated independently of overall population signal-to-noise ratio in order to test how the format of stored information affects learning. Higher noise correlations among similarly tuned units led to faster and more robust learning, favoring homogenous weights assigned to neurons within a functionally similar pool, and could emerge through Hebbian learning. When multiple discriminations were learned simultaneously, noise correlations across relevant feature dimensions sped learning whereas those across irrelevant feature dimensions slowed it. Our results complement existing theory on noise correlations by demonstrating that when such correlations are produced without significant degradation of the signal-to-noise ratio, they can improve the speed of readout learning by constraining it to appropriate dimensions.

Significance statement

Positive noise correlations between similarly tuned neurons theoretically reduce the representational capacity of the brain, yet they are commonly observed, emerge dynamically in complex tasks, and persist even in well-trained animals. Here we show that such correlations, when embedded in a neural population with a fixed signal to noise ratio, can improve the speed and robustness with which an appropriate readout is learned. In a simple discrimination task such correlations can emerge naturally through Hebbian learning. In more complex tasks that require multiple discriminations, correlations between neurons that similarly encode the task-relevant feature improve learning by constraining it to the appropriate task dimension.
Tau protein in smooth muscle cells and tissues
Authors: Shults Nataliia V. , Seeherman Sarah , Sariipek Nurefsan E. , Rybka Vladyslava , Marcocci Lucia , Gychka Sergiy G. , Ibrahim Yasmine F. , Suzuki Yuichiro J.
Published: October 2020

Tau is a microtubule-associated protein and plays a critical role in the pathophysiology of neurons. However, whether tau protein is expressed in smooth muscle cells is unknown. Here, we report that tau protein is expressed and is constitutively phosphorylated at threonine 181 in various smooth muscle cell types, including human cerebral artery smooth muscle cells, human pulmonary artery smooth muscle cells, and human bronchial airway smooth muscle cells. We also detected the expression of tau protein in the vascular smooth muscle of brain tissues from patients with systemic hypertension who died of ischemic stroke. Immunofluorescence staining revealed that phosphorylated tau at threonine 181 is more organized in the cell than does total tau protein. A protein phosphatase inhibitor, calyculin A induced the formation of higher molecular weight species of phosphorylated tau as visualized by Western blotting, indicating the occurrence of tau aggregation. Immunofluorescence also showed that calyculin A caused the aggregation of phosphorylated tau and disrupted the cytoskeletal organization. These results demonstrate the existence of tau protein in smooth muscle cells and tissues and that smooth muscle tau is susceptible to protein phosphorylation and aggregation.
A wildCucurbitagenome reveals the role of structural variants and introgression in domestication
Authors: Barrera-Redondo Josué , Sánchez-de la Vega Guillermo , Aguirre-Liguori Jonás A. , Castellanos-Morales Gabriela , Gutiérrez-Guerrero Yocelyn T. , Aguirre-Dugua Xitlali , Aguirre-Planter Erika , Tenaillon Maud I. , Lira-Saade Rafael , Eguiarte Luis E.
Published: October 2020

Despite their economic importance and well-characterized domestication syndrome, the genomic impact of domestication and the identification of variants underlying the domestication traits inCucurbitaspecies (pumpkins and squashes) is currently lacking.Cucurbita argyrosperma, also known as cushaw pumpkin or silver-seed gourd, is a Mexican crop consumed primarily for its seeds rather than fruit flesh. This makes it a good model to studyCucurbitadomestication, as seeds were an essential component of early Mesoamerican diet and likely the first targets of human-guided selection in pumpkins and squashes. We obtained population-level data using tunable Genotype by Sequencing libraries for 192 individuals of the wild and domesticated subspecies ofC. argyrospermaacross Mexico. We also assembled the first wildCucurbitagenome at a chromosome level. Comparative genomic analyses revealed several structural variants and presence/absence of genes related to domestication. Our results indicate a monophyletic origin of this domesticated crop in the lowlands of Jalisco. We uncovered candidate domestication genes that are involved in the synthesis and regulation of growth hormones, plant defense mechanisms, flowering time and seed development. The presence of shared selected alleles with the closely related speciesCucurbita moschatasuggests domestication-related introgression between both taxa.
Anatomical identification of the neuroendocrine system in theNothobranchius furzeribrain
Authors: Do Eunjeong , Kim Yumi
Published: October 2020

The hypophysis functions as a central gland of the neuroendocrine system for regulating fundamental body physiology. Upon aging, several hormones produced by the endocrine system are dramatically altered. Recently,Nothobranchius furzeri(the turquoise killifish) has become a popular model for aging studies because of its short lifespan and highly conserved aging phenotypes. However, the anatomical details of the major neuroendocrine system of the killifish have not been investigated so far. In this study, we have identified the pituitary and pineal glands of the turquoise killifish, which are critical components of the brain endocrine system. These two neuroendocrine glands were weakly attached to the main body of the killifish brain. The pineal gland was located on the dorsal part of the brain, while the pituitary gland was located on the ventral part. Brain sections containing pineal and pituitary glands were performed and revealed that cells in both the pituitary and pineal glands are densely placed than any other regions of brain. Further, three-dimensional images both in pineal and pituitary glands were uncovered their distinctive cellular arrangements. Vasopressin intestinal peptide (VIP) was strongly expressed in the neurohypophysis of the pituitary gland. Glial cells were found inside the pineal gland, while astrocytes covered the outside. These findings illustrate basic features of the neuroendocrine system ofNothobranchius furzeri.
Male brain processing of the body odor of ovulating women compared to that of pregnant women
Authors: Habel Ute , Regenbogen Christina , Kammann Catharina , Stickel Susanne , Chechko Natalia
Published: October 2020

Female chemical signals underlie the advertising of sexual receptivity and fertility. Whether the body odor of a pregnant woman also has a signaling function with respect to male behavior is yet to be conclusively established. This study examines how the body odors of ovulating and pregnant women differentially affect the behavior of heterosexual men.

Body odor samples were collected from 5 pregnant women and 5 matched controls during ovulation. In a double-blind functional magnetic resonance imaging design, 18 heterosexual men were exposed to female body odors during ovulation (OV) and pregnancy (PRG) while being required to indicate the attractiveness of concurrently presented female portrait images. The participants were also required to indicate whether they assumed a depicted woman was pregnant.

While neither OV nor PRG altered the perceived attractiveness of a presented face, the men tended to identify the women as pregnant while exposed to a PRG body odor. On the neural level, OV activated a network of the frontotemporal and limbic regions, while PRG activated the superior medial frontal gyrus.

The results suggest that the detection of sexual availability activates the male brain regions associated with face processing and reward/motivation, whereas sensing pregnancy activates a region responsible for empathy and prosocial behavior. Thus, the female body odor during pregnancy likely helps foster circumstances conducive to the future care of offspring while the body odor advertising sexual availability promotes mating behavior. The brains of heterosexual men may be capable of unconsciously discriminating between these two types of olfactory stimuli.
Spike-timing-dependent plasticity can account for connectivity aftereffects of dual-site transcranial alternating current stimulation
Authors: Schwab Bettina C. , König Peter , Engel Andreas K.
Published: October 2020

Transcranial alternating current stimulation (tACS), applied to two brain sites with different phase lags, has been shown to modulate stimulation-outlasting functional EEG connectivity between the targeted regions. Given the lack of knowledge on mechanisms of tACS aftereffects, it is difficult to further enhance effect sizes and reduce variability in experiments. In this computational study, we tested if spike-timing-dependent plasticity (STDP) can explain stimulation-outlasting connectivity modulation by dual-site tACS and explored the effects of tACS parameter choices. Two populations of spiking neurons were coupled with synapses subject to STDP, and results were validated via a re-analysis of EEG data. Our simulations showed stimulation-outlasting connectivity changes between in- and anti-phase tACS, dependent on both tACS frequency and synaptic conduction delays. Importantly, both a simple network entraining to a wide range of tACS frequencies as well as a more realistic network that spontaneously oscillated at alpha frequency predicted that the largest effects would occur for short conduction delays between the stimulated regions. This finding agreed with experimental EEG connectivity modulation by 10 Hz tACS, showing a clear negative correlation of tACS effects with estimated conduction delays between regions. In conclusion, STDP can explain connectivity aftereffects of dual-site tACS. However, not all combinations of tACS frequency and application sites are expected to effectively modulate connectivity via STDP. We therefore suggest using appropriate computational models and/or EEG analysis for planning and interpretation of dual-site tACS studies relying on aftereffects.

Highlights

Network model with STDP explains EEG connectivity change after dual-site tACS

Effects are predicted to depend on tACS frequency and conduction delays

EEG data confirm dependence on conduction delays between regions

Model can be used to estimate and maximize experimental effects
Spatiotemporal shifts in the role of floral traits in shaping tropical plant-pollinator interactions
Authors: Klomberg Yannick , Tropek Robert , Mertens Jan E.J. , Kobe Ishmeal N. , Hodeček Jiří , Raška Jan , Fominka Nestoral T. , Souto-Vilarós Daniel , Janeček Štěpán
Published: October 2020

The pollination syndrome hypothesis predicts that plants pollinated by the same pollinator group bear convergent combinations of specific floral traits. Nevertheless, some studies have shown relatively low predictive power for these floral trait combinations. This discrepancy may be caused by changes in the importance of specific floral traits for shaping interactions under different environmental conditions and for different pollinator groups. To test this, we studied pollination systems and floral traits along an elevational gradient on Mount Cameroon during wet and dry seasons. Using Random Forest models, allowing the ranking of traits by significance, we demonstrated that some floral traits are more important than others in shaping interactions and that these traits predict pollinators relatively well. However, the distribution and importance of traits varies under different environmental conditions. Our results imply the need to improve our trait-based understanding of plant-pollinator interactions to better inform the debate surrounding pollination syndrome hypothesis.
Bent crystal Laue analyser combined with total reflection fluorescence X-ray absorption fine structure (BCLA + TRF-XAFS) and its application to surface studies
Authors: Wakisaka Yuki , Hu Bing , Kido Daiki , Al Rashid Md. Harun , Chen Wenhan , Dong Kaiyue , Wada Takahiro , Bharate Bapurao , Yuan Quiyi , Mukai Shingo , Takeichi Yasuo , Takakusagi Satoru , Asakura Kiyotaka
Published: October 2020

A bent crystal Laue analyser (BCLA) is an X-ray energy analyser used for fluorescence X-ray absorption fine-structure (XAFS) spectroscopy to separate the fluorescence X-ray emission line of a target atom from the elastic scattering X-rays and other fluorescence emission lines. Here, the feasibility of the BCLA for total reflection fluorescence XAFS (TRF-XAFS), which has a long X-ray footprint on the substrate surface owing to grazing incidence, was tested. The focal line of the BCLA was adjusted on the X-ray footprint and the XAFS signal for one monolayer of Pt deposited on a 60 nm Au film with high sensitivity was obtained. Although range-extended XAFS was expected by the rejection of Au fluorescence arising from the Au substrate, a small glitch was found in the AuL3edge because of the sudden change of the complex refraction index of the Au substrate at the Au edge. This abnormal spectrum feature can be removed by reflectivity correction using Au foil absorption data. BCLA combined with TRF-XAFS spectroscopy (BCLA + TRF-XAFS) is a new technique for thein situsurface analysis of highly dispersed systems even in the presence of a liquid overlayer.
The impact of high-performance human resource practices on the research performance and career success of academics in Saudi Arabia
Authors: Alshaikhmubarak Abdulrahman , Da Camara Nuno , Baruch Yehuda
Published: October 2020

Purpose

This paper explores the impact of high-performance human resource practices (HPHRPs) on the research performance and career success of academics.

Design/methodology/approach

Survey data was collected from 586 faculty members in the five largest public universities in Saudi Arabia.

Findings

The findings suggest that the HPHRPs of internal mobility and recognition had a strong impact on faculty members' career success and that these relationships were mediated by research performance. In addition, the study also found that the HPHRPs of training and recognition positively influenced research performance, while, surprisingly, the HPHRPs of participation in decision-making were found to have a negative effect on faculty members' research performance.

Originality/value

This study is original in combining research in human resource management (HRM) and career studies to develop a model that explains academic research performance and career success from the lens of HR practices. The results also provide leaders in Saudi Arabia's public higher education sector with empirical data on the impact of HPHRPs on academic research performance and career success.
Risk reporting in financial crises: a tale of two countries
Authors: Lajili Kaouthar , Dobler Michael , Zéghal Daniel , Bryan Mitchell John
Published: October 2020

Purpose

This paper aims to investigate the attributes and information content of risk reporting in two different institutional and regulatory, namely, Canadian and German, settings during the period surrounding the financial crisis of 2008.

Design/methodology/approach

For a matched sample of manufacturing firms in the period 2006–2010, this study conducts a detailed content analysis of annual reports to assess and compare the volume and patterns of risk disclosures. Panel regressions are used to explore how risk disclosures related to corporate risk proxies and performance indicators.

Findings

Over the sample period, Canadian and German firms increase the volume but largely maintain the patterns of risk disclosures. Risk disclosures relate to corporate risk proxies but are not incrementally informative to assess firm performance.

Originality/value

The paper contributes to research on risk reporting by providing detailed cross-country evidence for a period particularly shaped by significant risk. The findings have implications for the regulation and usefulness of risk reporting.
Antecedents of perceived beneficial destination image: a study on Middle-Eastern medical tourists visit Iran
Authors: Chelliah Shankar , Khan Mohammad Jamal , Atabakhshi Kashi Amir Bahador
Published: October 2020

Purpose

This study aims to investigate the relationship between travel motivation, perceived risks, travel constraints and perceived beneficial destination image that leads to visit intention among Middle-Eastern medical tourists. Some previous studies have explained these factors in detail, however, studies that explore the relationship between these factors in the Iranian context is scarce. Moreover, there are relatively very few studies, which focused on actual medical tourists in empirical investigation, therefore, there is still a lack of clarity in the literature regarding travel behavior and travel decision-making of medical tourists.

Design/methodology/approach

A quantitative study was performed on 161 Middle-Eastern medical tourists who visited Iran in early months of 2018. Purposive sampling method was used to collect the data from two private hospitals. Structural equation modeling with partial least square (PLS) approach was used and PLS 3.2.8 data analysis tool was used to test the hypotheses.

Findings

The data analysis results have found that perceived destination image was the strongest predictor of visit intention among medical tourists. The results have also found a positive effect of travel motivation and negative effect of perceived travel risks on perceived beneficial destination image.

Originality/value

This study aims to enrich the body of knowledge by investigating the relationship between the factors, which have important roles in travel behavior and decision-making of medical tourists. The study also bridges the gap in the literature by explaining the behavior of actual medical tourists. The findings of the study provide the much needed insight on the behavioral intention of medical tourists, which will help the service providers and policymakers to reform their strategies and policies accordingly.
Management and business history – a reflexive research agenda for the 2020s
Authors: Tennent Kevin Daniel
Published: October 2020

Purpose

The purpose of this paper is to reflect back over his career as a management and business historian so far as to consider opportunities for the future of management and business history as a disciplinary area.

Design/methodology/approach

The paper consists of two segments – the first half is an auto-ethnographic personal reflection looking at the author’s research journey and how the discipline as experienced by the author has evolved over that time. The second half is a prescriptive look forward to consider how we should leverage the strengths as historians to progress the discipline forward.

Findings

The paper demonstrates opportunities for management and business history to encompass new agendas including the expansion of the topic into teaching, the possibility for the advancement of empirical contributions and opportunities for findings in new research areas, including the global south and public and project management history.

Originality/value

The paper demonstrates that historians should be more confident in the disciplinary capabilities, particularly their understandings of historic context, continuity, change and chronologies when making empirical and theoretical contributions.
Leadership-in-teams, ready, willing and able: perspectives of international accounting students
Authors: Oosthuizen Heinrich , De Lange Paul , Wilmshurst Trevor , Beatson Nicola
Published: October 2020

Purpose

The purpose of this study is to explore the reasons why international accounting students in higher education in Australia do not accept leadership roles in academic teams, considering the importance employers attach to leadership and teamwork graduate attributes.

Design/methodology/approach

Adopting the Keatinget al.(2014) ready, willing and able (RWA) leadership framework, this qualitative study uses a narrative textual approach to analyse the data from responses to open-ended questions recorded in interviews with a sample of Master of Professional Accounting (MPA) students (N = 12) undertaking leadership-in-team roles in a management and cost Accounting unit (N = 110) within an Australian higher education accounting program.

Findings

The results of this study suggest that a lack of past work experience disadvantages accounting students in being ‘ready’ to adopt leadership roles in teams. Self-interested behaviour results in students not being ‘willing’ to adopt leadership roles. Students perceive business simulation and work-integrated learning activities to hold the potential to improve their ‘ability’ to lead.

Practical implications

The study offers a conceptual schema for student leadership development, suggesting that accounting curricula in higher education should include the assessment of scaffolded leadership development activities. Mentorship roles in academic teams should also be explored.

Originality/value

To the authors’ knowledge, this is the first application of the RWA framework to explore accounting students’ predisposition to accepting leadership roles in teams. Informed by the student narrative, the authors offer a future focused RWA schema as a practical guide for educators to embed leadership development in the accounting curriculum.
Economic growth and methane emission: testing the EKC hypothesis in ASEAN economies
Authors: Adeel-Farooq Rana Muhammad , Raji Jimoh Olajide , Adeleye Bosede Ngozi
Published: October 2020

Purpose

The purpose of this study is to analyze the Environmental Kuznets Curve (EKC) hypothesis within the methane (CH4) emission–economic growth nexus among the six Association of Southeast Asian Nations (ASEAN) countries from 1985 to 2012.

Design/methodology/approach

The study employs dynamic panel data estimation approaches such as mean group (MG) and pooled MG (PMG) techniques.

Findings

The findings reveal that the EKC hypothesis for the CH4 emission in these economies proves to be valid. In other words, economic growth causes CH4 emissions to decrease. Nevertheless, energy consumption is deteriorating the environment by enhancing CH4 emissions in these countries.

Originality/value

The ASEAN region has experienced substantial economic growth over the previous few decades. Nevertheless, pollution has also increased manifolds in this region. Methane is a more potent greenhouse gas (GHG) as compared to carbon dioxide (CO2) and a major source of socio-economic issues in the ASEAN region. This study is the first in the existing literature on the EKC hypothesis examining the role of economic growth on CH4 emissions in the selected ASEAN countries. The outcomes of this study could be really beneficial for the policymakers in this region regarding sustainability and economic development.
Corruption scandals in six Asian countries: a comparative analysis
Authors: Quah Jon S.T.
Published: October 2020

Purpose

The purpose of this paper is to compare and evaluate how the governments in six Asian countries have dealt with selected grand corruption scandals.

Design/methodology/approach

This paper is based on the comparative analysis of 11 corruption scandals examined in the six articles on India, Japan, Macau, Malaysia, Philippines and Singapore included in this special issue ofPublic Administration and Policy.

Findings

The responses of the governments in the six countries depend on the strength of their political will in combating corruption. The responses of the governments in Malaysia, Philippines, India and Japan reflect their weak political will in combating corruption and lack of accountability of the corrupt offenders. By contrast, the strong political will of the governments in Singapore and Macau is reflected in the investigation and punishment of the corrupt offenders without any cover-up of the scandals.

Originality/value

The findings would be of interest to scholars, policymakers and anti-corruption practitioners and activists.
Institutionalising federalism in Nepal: operationalising obstacles, procrastinated progress
Authors: Acharya Keshav Kumar , Zafarullah Habib
Published: October 2020

Purpose

The purpose of this paper is to explore how local government bodies in Nepal are empowered to play their constitutional roles and engage in activities to deliver public services at the doorsteps of the people effectively. The focus is on the institutionalisation of federalism, its implications for local governance, and capacity development of local authorities.

Design/methodology/approach

Ideas of decentralisation, governance and public management have been used to interpret findings based on qualitative research methods by key informant interviews, focus group discussions and personal observations conducted in five selected municipalities in Nepal.

Findings

The process of operationalising the power of local government bodies is more conventional and hierarchic. At the same time, the formulation and implementation of inclusive plans and budgeting are confined with certain formalities that do not necessarily allow citizens the space for voices. Federal government grants constrain fiscal jurisdiction and control over resource mobilisation. The mere preparation and administration of local government legislation and relevant by-laws have weakened the capacity of local government bodies.

Originality/value

From interpretation of first-hand data, this paper has identified the pitfalls of the federalisation process, the constraints deter the devolution of power to local bodies as well as the transformation of local governments into autonomous institutions in Nepal.
Representative and responsive bureaucracy in Nepal: a mismatch or a realistic assumption?
Authors: Jamil Ishtiaq , Baniamin Hasan Muhammad
Published: October 2020

Purpose

The purpose of this paper is to investigate, firstly, to what extent has Nepal’s bureaucracy become representative in terms of reflecting the country’s demographic composition, and secondly, has the bureaucracy become more responsive to citizens since the implementation of a quota policy in 2007.

Design/methodology/approach

This paper relies on factual and perceptual data in analysis. In order to analyze and interpret representative bureaucracy, this paper adopts factual data derived from the secondary sources, especially data generated by the Government of Nepal. Second, the perceptual set of data was collected through two rounds (2008, 2014) of a country-representative survey in Nepal.

Findings

The findings suggest that in terms of representativeness, the bureaucracy is still dominated by high-caste Hindus, while other ethnic communities, except the Newars, are utterly under-represented. Surprisingly, Dalits are represented in higher posts as per their percentage in the population, but they are still underrepresented in the civil service in general. Women’s representation has also increased through participation in the civil service, but they still mostly hold junior or non-gazetted posts. Citizens’ evaluations regarding responsiveness and processes of service provision are also mixed.

Originality/value

This paper is a unique attempt to understand the aspects of representativeness and responsiveness in relation to Nepalese Civil Service.