bluuebunny/crossref_metadata_2025 huggingface dataset:
Adaptive learning through temporal dynamics of state representation
Authors: Razmi Niloufar , Nassar Matthew R.
Published: August 2020

People adjust their learning rate rationally according to local environmental statistics and calibrate such adjustments based on the broader statistical context. To date, no theory has captured the observed range of adaptive learning behaviors or the complexity of its neural correlates. Here, we attempt to do so using a neural network model that learns to map an internal context representation onto a behavioral response via supervised learning. The network shifts its internal context upon receiving supervised signals that are mismatched to its output, thereby changing the “state” to which feedback is associated. A key feature of the model is that such state transitions can either increase learning or decrease learning depending on the duration over which the new state is maintained. Sustained state transitions that occur after changepoints facilitate faster learning and mimic network reset phenomena observed in the brain during rapid learning. In contrast, state transitions after one-off outlier events are short-lived, thereby limiting the impact of outlying observations on future behavior. State transitions in our model provide the first mechanistic interpretation for bidirectional learning signals, such the p300, that relate to learning differentially according to the source of surprising events and may also shed light on discrepant observations regarding the relationship between transient pupil dilations and learning. Taken together, our results demonstrate that dynamic latent state representations can afford normative inference and provide a coherent framework for understanding neural signatures of adaptive learning across different statistical environments.

Significance Statement

How humans adjust their sensitivity to new information in a changing world has remained largely an open question. Bridging insights from normative accounts of adaptive learning and theories of latent state representation, here we propose a feed-forward neural network model that adjusts its learning rate online by controlling the speed of transitioning its internal state representations. Our model proposes a mechanistic framework for explaining learning under different statistical contexts, explains previously observed behavior and brain signals, and makes testable predictions for future experimental studies.
Time-course transcriptome landscape of achene development in lettuce
Authors: Luo Chen , Wang Shenglin , Ning Kang , Chen Zijing , Yang Jingjing , Wang Yixin , Qi Meixia , Wang Qian
Published: August 2020

Lettuce (Lactuca sativaL.), which belongs to the large Asteraceae (Compositae) family, breeds by sexual reproduction and produce seeds. Actually, lettuce seeds are achenes, which are defined as fruits. However, few studies have described the morphological characteristics of the lettuce achenes, and genes essential for achene development are largely unknown in lettuce. To investigate the gene activity during achene development and determine the possible mechanisms that influence achene development in lettuce, we performed a time-course transcriptome analysis of lettuce achenes. A total of 23,790 expressed genes were detected at the five achene development stages. We investigated the gene expression patterns during achene development and identified the enriched biological processes at the corresponding stages. Kyoto Encyclopedia of Genes and Genomes and Gene Ontology analyses revealed a variety of transcriptomic similarities and differentiation at different achene development stages. Further, transcription factors and phytohormones were found to play important roles during achene development. Finally, we proposed a working model to illustrate the gene expression modules and possible molecular mechanism underlying achene development. Our time-course transcriptome data also provides a foundation for future functional studies to reveal the genetic control of achene development in lettuce.
Single-cell identity definition using random forests and recursive feature elimination
Authors: Park Madeline , Vorperian Sevahn , Wang Sheng , Pisco Angela Oliveira
Published: August 2020

Single-cell RNA sequencing (scRNA-seq) enables the detailed examination of a cell’s underlying regulatory networks and the molecular factors contributing to its identity. We developed scRFE with the goal of generating interpretable gene lists that can accurately distinguish observations (single-cells) by their features (genes) given a metadata category of the dataset. scRFE is an algorithm that combines the classical random forest classifier with recursive feature elimination and cross validation to find the features necessary and sufficient to classify cells in a single-cell RNA-seq dataset by ranking feature importance. It is implemented as a Python package compatible with Scanpy, enabling its seamless integration into any single-cell data analysis workflow that aims at identifying minimal transcriptional programs relevant to describing metadata features of the dataset. We applied scRFE to the Tabula Muris Senis and reproduced established aging patterns and transcription factor reprogramming protocols, highlighting the biological value of scRFE’s learned features.

Author summary

scRFE is a Python package that combines a random forest classifier with recursive feature elimination and cross validation to find the features necessary and sufficient to classify cells in a single-cell RNA-seq dataset by ranking feature importance. scRFE was designed to enable straightforward integration as part of any single-cell data analysis workflow that aims at identifying minimal transcriptional programs relevant to describing metadata features of the dataset.
Data-driven causal analysis of observational time series in ecology
Authors: Yuan Alex E , Shou Wenying
Published: August 2020

Complex ecosystems are challenging to understand as they often defy manipulative experiments for practical or ethical reasons. In response, several fields have developed parallel approaches to infer causal relations from observational time series. Yet these methods are easy to misunderstand and often controversial. Here, we provide an accessible and critical review of three statistical causal inference approaches popular in ecological time series analysis: pairwise correlation, Granger causality, and state space reconstruction. For each, we ask what a method tests for, what causal statement it might imply, and when it could lead us astray. We devise new ways of visualizing key concepts, describe some novel pathologies of causal inference methods, and point out how so-called “model-free” causality tests are not assumption-free. We hope that our synthesis will facilitate thoughtful application of causal inference approaches and encourage explicit statements of assumptions.
An extension of Shannon’s entropy to explain taxa diversity and human diseases
Authors: Kamari Farzin , Dadmand Sina
Published: August 2020

In this study, with the use of the information theory, we have proposed and proved a mathematical theorem by which we argue the reason for the existence of human diseases. To introduce our theoretical frame of reference, first, we put forward a modification of Shannon’s entropy, computed for all available proteomes, as a tool to compare systems complexity and distinguish between the several levels of biological organizations. We establish a new approach to differentiate between several taxa and corroborate our findings through the latest tree of life. Furthermore, we found that human proteins with higher mutual information, derived from our theorem, are more prone to be involved in human diseases. We further discuss the dynamics of protein network stability and offer probable scenarios for the existence of human diseases and their varying occurrence rates. Moreover, we account for the reasoning behind our mathematical theorem and its biological inferences.
A Bayesian analysis of the association betweenLeukotriene A4 Hydrolasegenotype and survival probability of tuberculous meningitis patients treated with adjunctive dexamethasone
Authors: Whitworth Laura , Coxon Jacob , van Laarhoven Arjan , Thuong Nguyen Thuy Thuong , Dian Sofiati , Alisjahbana Bachti , Ganiem Ahmad Rizal , van Crevel Reinout , Thwaites Guy , Troll Mark , Edelstein Paul , Sewell Roger , Ramakrishnan Lalita
Published: August 2020

Tuberculous meningitis (TBM) remains the most devastating form of tuberculosis (TB) with high mortality despite effective antimicrobial treatment. As mortality has been linked to excessive inflammation, anti-inflammatory glucocorticoids are now routinely used as adjunctive treatment with antimicrobial therapy. However, they reduce mortality by only ~ 30%, raising the possibility that only a subset of TBM deaths are caused by inflammatory pathophysiology. Studies in Vietnam found that the survival benefit of adjunctive glucocorticoids was limited to individuals with a common promoter variant in theleukotriene A4 hydrolase(LTA4H) gene encoding an enzyme that regulates inflammatory eicosanoid expression. The variant constitutes a C/T transition with TT homozygotes having increased expression over CT heterozygotes and CC homozygotes. In Vietnam, theLTA4HTT genotype predicted survival, consistent with dexamethasone benefiting only those individuals with a dysregulated hyper-inflammatory response. However, a study of TBM patients in Indonesia did not find theLTA4HTT genotype to confer a significant survival benefit. Given the potential of personalized life-saving anti-inflammatory therapies guided byLTA4Hgenotype, we have used Bayesian methods to analyze the data from both studies. Bayesian analysis reveals that theLTA4HTT genotype confers survival benefit in both the Vietnam and Indonesia cohorts that begins within days and continues long-term. However, its benefit is nullified in the most severe cases where other factors cause early mortality.LTA4HTT genotype is associated with increased survival in HIV-positive patients also. Thus, our analysis extends the association ofLTA4Hgenotype with TBM survival to populations outside of Vietnam and to HIV-positive patients. PatientLTA4Hgenotyping used in conjunction with disease severity assessment may help to target glucocorticoids to patients most likely to benefit from this broadly-acting immunosuppressive regimen despite its significant adverse effects.
Threshold accumulation of a constitutive protein explainsE. colicell division behavior in nutrient upshifts
Authors: Panlilio Mia , Grilli Jacopo , Tallarico Giorgio , Iuliani Ilaria , Sclavi Bianca , Cicuta Pietro , Lagomarsino Marco Cosentino
Published: August 2020

Despite of a boost of recent progress in dynamic single-cell measurements and analyses inE. coli, we still lack a mechanistic understanding of the determinants of the decision to divide. Specifically, the debate is open regarding the processes linking growth and chromosome replication to division, and on the molecular origin of the observed “adder correlations”, whereby cells divide adding roughly a constant volume independent of their initial volume. In order to gain insight into these questions, we interrogate dynamic size-growth behavior of single cells across nutrient upshifts with a high-precision microfluidic device. We find that the division rate changes quickly after nutrients change, much before growth rate goes to a steady state, and in a way that adder correlations are robustly conserved. Comparison of these data to simple mathematical models falsifies proposed mechanisms where replication-segregation or septum completion are the limiting step for cell division. Instead, we show that the accumulation of a putative constitutively expressed “P-sector divisor” protein explains the behavior during the shift.

Significance statement

The mechanism leading to cell division in the bacteriumE. coliis unknown, but we know that it results in adding a roughly constant size every cell cycle, regardless of size at birth. While most available studies try to infer information on cell division from steadily dividing cells in constant nutrient conditions, this study leverages on a high-resolution device to monitor single-cell growth division upon nutrient changes. Comparing these data with different mathematical models, the authors are able to discriminate among fundamentally different mechanisms of cell division control, and they show that the data support a model where an unregulated protein accumulates to a threshold and triggers division.
Change in liana density over 30 years in a Bornean rain forest supports the escape hypothesis
Authors: Newbery D. M. , Zahnd C.
Published: August 2020

Liana dynamics may influence tree dynamics and vice versa. Only long-term studies can perhaps disentangle them. In two permanent plots of lowland dipterocarp forest at Danum a liana census in 1988 was repeated in 2018. The primary forest was still in a late stage of recovery from an inferred large and natural disturbance in the past. Mean number of lianas per tree decreased by 22 and 34% in plots 1 and 2, and in different ways. By 2018 there were relatively more trees with few lianas and relatively fewer trees with many lianas than in 1988. The redistribution was strongest for overstorey trees of the Dipterocarpaceae (more with no lianas by 2018) and understorey trees of the Euphorbiaceae (many losing high loads in especially plot 2). Proportion of trees with lianas increased overall by 3.5%. Number of lianas per tree showed a quadratic relationship with tree size: maximal for large trees, fewer for smaller and very large trees. Tree survival and stem growth rate were significantly negatively related to the number of lianas after accounting for spatial autocorrelation. Monte Carlo random subsampling of trees in 1988 and 2018, to achieve statistical independence, established significance of change. Dipterocarps and euphorbs clearly differed in their liana dynamics between plots. Regression models had different forms for the two plots, which reflected a complicated structural-spatial variability in host-liana dynamics. Analysis of the abundant tree species individually, highlighted a group of emergent dipterocarps with low liana counts decreasing with time. Building on an earlier hypothesis for this forest type and site, these very large trees appear to have been losing their lianas by branch shedding, as they moved into and out of the main canopy. They were evidently ‘escaping’ from the parasite. The process may in part explain the characteristically very uneven forest canopy at Danum. Change in liana density was therefore contingent on both forest history and site succession, and on plot-level structure and tree dynamics. Liana promotion in the intermittent ENSO dry periods was seemingly being offset by closing of the forest and dominance by dipterocarps in late seral stages.
Greater TMS-evoked frontoparietal effective connectivity is correlated with better cognitive performance
Authors: Morris Timothy P. , Redondo-Camos Maria , Cattaneo Gabriele , Macia Didac , Solana-Sanchez Javier , Espanya-Irla Goretti , Delgado-Gallén Selma , Alviarez-Schulze Vanessa , Pachón-Garcia Catherine , Santarnecchi Emiliano , Tadayon Ehsan , Ozdemir Recep , Muñoz Jose Ma Tormos , Batres-Faz David , Pascual-Leone Alvaro , Shafi Mouhsin M.
Published: August 2020

Fronto-parietal activity has been related to fluid intelligence and flexible cognitive control. However, causal insights on this relation are lacking. We used real-time integration of MRI-guided TMS and EEG to characterize the spatial and temporal properties of signal propagation between these two regions and relate them to cognitive performance.

31 healthy adults (55 ±6 years, 20 female) underwent TMS-EEG and a full cognitive assessment. Local and propagated current from 5 source space-reconstructed scouts ipsilateral to two stimulation sites (pre frontal cortex (PFC) and inferior parietal lobule (IPL)) was quantified in two-time windows (15-40ms and 40-80ms) and related to domain-general (global cognition) and domain-specific (memory, working memory, reasoning, flexibility, lexical access and visuo-spatial) cognitive functions.

TMS-evoked activity from stimulation of the PFC and the IPL resulted in local and distributed activity across frontoparietal regions. TMS-evoked activity in local regions was not correlated with cognitive functions. In response to TMS of the PFC, propagated current to the distal superior parietal scout in the first 15-40ms was significantly associated with global cognition (β = 2.63, SE = .898,p= .008, R2= .31). Similarly, following TMS of the IPL, propagation to the middle prefrontal gyrus scout (15-40ms) was significantly associated with global cognition (β = 2.67, SE = 1.289,p= .025, R2= .27). In an exploratory step, domain-specific correlations were seen in the PFC condition.

Locally evoked activity measured via source space reconstruction from TMS of two association hubs is not associated with cognitive functions. However, the propagation of the TMS pulse through frontoparietal connections is associated with overall cognitive ability. These associations are driven by a number of cognitive domains in the PFC stimulation condition.
SARS-CoV-2 ORF6 disrupts nucleocytoplasmic transport through interactions with Rae1 and Nup98
Authors: Addetia Amin , Lieberman Nicole A. P. , Phung Quynh , Xie Hong , Roychoudhury Pavitra , Shrestha Lasata , Loprieno Michelle , Huang Meei-Li , Jerome Keith R. , Greninger Alexander L.
Published: August 2020

RNA viruses that replicate in the cytoplasm often disrupt nucleocytoplasmic transport to preferentially translate their own transcripts and prevent host antiviral responses. TheSarbecovirusaccessory protein ORF6 has previously been shown to be the major inhibitor of interferon production in both SARS-CoV and SARS-CoV-2. SARS-CoV-2 ORF6 was recently shown to co-purify with the host mRNA export factors Rae1 and Nup98. Here, we demonstrate SARS-CoV-2 ORF6 strongly represses protein expression of co-transfected reporter constructs and imprisons host mRNA in the nucleus, which is associated with its ability to co-purify with Rae1 and Nup98. These protein-protein interactions map to the C-terminus of ORF6 and can be abolished by a single amino acid mutation in Met58. Overexpression of Rae1 restores reporter expression in the presence of SARS-CoV-2 ORF6. We further identify an ORF6 mutant containing a 9-amino acid deletion, ORF6 Δ22-30, in multiple SARS-CoV-2 clinical isolates that can still downregulate the expression of a co-transfected reporter and interact with Rae1 and Nup98. SARS-CoV ORF6 also interacts with Rae1 and Nup98. However, SARS-CoV-2 ORF6 more strongly co-purifies with Rae1 and Nup98 and results in significantly reduced expression of reporter proteins compared to SARS-CoV ORF6, a potential mechanism for the delayed symptom onset and pre-symptomatic transmission uniquely associated with the SARS-CoV-2 pandemic.

Importance

SARS-CoV-2, the causative agent of COVID-19, is an RNA virus with a large genome that encodes accessory proteins. While these accessory proteins are not required for growthin vitro, they can contribute to the pathogenicity of the virus. One of SARS-CoV-2’s accessory proteins, ORF6, was recently shown to co-purify with two host proteins, Rae1 and Nup98, involved in mRNA nuclear export. We demonstrate SARS-CoV-2 ORF6 interaction with these proteins is associated with reduced expression of a reporter protein and accumulation of poly-A mRNA within the nucleus. SARS-CoV ORF6 also shows the same interactions with Rae1 and Nup98. However, SARS-CoV-2 ORF6 more strongly represses reporter expression and co-purifies with Rae1 and Nup98 compared to SARS-CoV ORF6. The ability of SARS-CoV-2 ORF6 to more strongly disrupt nucleocytoplasmic transport than SARS-CoV ORF6 may partially explain critical differences in clinical presentation between the two viruses.
Exploring the boundaries of microbial habitability in soil
Authors: Dragone Nicholas B. , Diaz Melisa A. , Hogg Ian , Lyons W. Berry , Jackson W. Andrew , Wall Diana H. , Adams Byron J. , Fierer Noah
Published: August 2020

Microbes are widely assumed to be capable of colonizing even the most challenging terrestrial surface environments on Earth given enough time. We would not expect to find surface soils uninhabited by microbes as soils typically harbor diverse microbial communities and viable microbes have been detected in soils exposed to even the most inhospitable conditions. However, if uninhabited soils do exist, we might expect to find them in Antarctica. We analyzed 204 ice-free soils collected from across a remote valley in the Transantarctic Mountains (84 – 85°S, 174 – 177°W) and were able to identify a potential limit of microbial habitability. While most of the soils we tested contained diverse microbial communities, with fungi being particularly ubiquitous, microbes could not be detected in many of the driest, higher elevation soils - results that were confirmed using cultivation-dependent, cultivation-independent, and metabolic assays. While we cannot confirm that this subset of soils is completely sterile and devoid of microbial life, our results do show that microbial habitability and activity can be restricted by near-continuous exposure to cold, dry, and salty conditions, establishing the environmental conditions that constrain habitability in terrestrial surface environments. Constant exposure to these conditions for thousands of years has generated uninhabited surface soil environments, with either no detectable microbes or conditions which are not suitable to sustain microbial activity. Such uninhabited soils are unlikely to be unique to the studied region with this work challenging expectations about where microbes might, or might not, be able to thrive on Earth and other planets.

Significance Statement

Certain surface soils in Antarctica have remained effectively uninhabited due to a near-continuous exposure to cold-dry-salty conditions. This is an unexpected result because soils, even those in hyper-arid deserts, typically contain detectable microorganisms. Additionally, the prevalence of fungi at the colder, drier, higher elevation sites suggests that certain fungi may in fact be better adapted than bacteria or archaea to some of the most challenging soil environments on Earth.
Noise-robust recognition of objects by humans and deep neural networks
Authors: Jang Hojin , McCormack Devin , Tong Frank
Published: August 2020

Deep neural networks (DNNs) for object classification have been argued to provide the most promising model of the visual system, accompanied by claims that they have attained or even surpassed human-level performance. Here, we evaluated whether DNNs provide a viable model of human vision when tested with challenging noisy images of objects, sometimes presented at the very limits of visibility. We show that popular state-of-the-art DNNs perform in a qualitatively different manner than humans – they are unusually susceptible to spatially uncorrelated white noise and less impaired by spatially correlated noise. We implemented a noise-training procedure to determine whether noise-trained DNNs exhibit more robust responses that better match human behavioral and neural performance. We found that noise-trained DNNs provide a better qualitative match to human performance; moreover, they reliably predict human recognition thresholds on an image-by-image basis. Functional neuroimaging revealed that noise-trained DNNs provide a better correspondence to the pattern-specific neural representations found in both early visual areas and high-level object areas. A layer-specific analysis of the DNNs indicated that noise training led to broad-ranging modifications throughout the network, with greater benefits of noise robustness accruing in progressively higher layers. Our findings demonstrate that noise-trained DNNs provide a viable model to account for human behavioral and neural responses to objects in challenging noisy viewing conditions. Further, they suggest that robustness to noise may be acquired through a process of visual learning.
Detection of alternative splicing inDiabrotica virgifera virgiferaLeConte, in association with Bt resistance using RNA-seq and PacBio Iso-Seq
Authors: Zhao Zixiao , Elsik Christine G. , Hibbard Bruce E. , Shelby Kent S.
Published: August 2020

Background

Alternative splicing is one of the major mechanisms that increases transcriptome diversity in eukaryotes, including insect species that have gained resistance to pesticides and Bt toxins. In western corn rootworm (Diabrotica virgifera virgiferaLeConte), neither alternative splicing nor its role in resistance to Bt toxins has been studied.

Results

To investigate the mechanisms of Bt resistance we carried out single-molecule real-time (SMRT) transcript sequencing and Iso-seq analysis on resistant, eCry3.1Ab-selected and susceptible, unselected, western corn rootworm neonate midguts which fed on seedling maize with and without eCry3.1Ab for 12 and 24 hours. We present transcriptome-wide alternative splicing patterns of western corn rootworm midgut in response to feeding on eCry3.1Ab-expressing corn using a comprehensive approach that combines both RNA-seq and SMRT transcript sequencing techniques. We found that 67.73% of multi-exon genes are alternatively spliced, which is consistent with the high transposable element content of the genome. One of the alternative splicing events we identified was a novel peritrophic matrix protein with two alternative splicing isoforms. Analysis of differential exon usage between resistant and susceptible colonies showed that in eCry3.1Ab-resistant western corn rootworm, expression of one isoform was significantly higher than in the susceptible colony, while no significant differences between colonies were observed with the other isoform.

Conclusion

Our results provide the first survey of alternative splicing in western corn rootworm and suggest that the observed alternatively spliced isoforms of peritrophic matrix protein may be associated with eCry3.1Ab resistance in western corn rootworm.
Striatal low-threshold spiking interneurons locally gate dopamine during learning
Authors: Holly Elizabeth N. , Davatolhagh M. Felicia , España Rodrigo A. , Fuccillo Marc V.
Published: August 2020

Low-threshold spiking interneurons (LTSIs) in the dorsomedial striatum are potent modulators of goal-directed learning. Here, we uncover a novel function for LTSIs in locally and directly gating striatal dopamine, using in vitro fast scan cyclic voltammetry as well as in vivo GRAB-DA sensor imaging and pharmacology during operant learning. We demonstrate that LTSIs, acting via GABAB signaling, attenuate dopamine release, thereby serving as local coordinators of striatal plasticity.
Genome-wide association study of TP53 R249S mutation in hepatocellular carcinoma with aflatoxin B1 exposure and hepatitis B virus infection in Guangxi
Authors: Han Chuangye , Yu Tingdong , Qin Wei , Liao Xiwen , Huang Jianlu , Liu Zhengtao , Yu Long , Liu Xiaoguang , Chen Zhiwei , Yang Chengkun , Wang Xiangkun , Mo Shutian , Zhu Guangzhi , Su Hao , Mo Zengnan , Peng Tao
Published: August 2020

Background/Aims

Dietary aflatoxin B1 (AFB1) exposure, which induces DNA damage and codon 249 mutation of the TP53 gene, is one of the major risk factors for hepatocellular carcinoma (HCC). Hepatitis B virus (HBV) infection and AFB1 exert synergistic effects to promote carcinogenesis and TP53 R249S mutation in HCC.

Methods

A genome-wide association study (GWAS) was conducted on 485 cases of HCC with chronic HBV infection, followed by a two-stage replication study on 270 cases with chronic HBV infection. Susceptibility variants for the TP53 R249S mutation in HCC were identified based on both GWAS and replication analysis. The associations of identified variants with expression levels of their located genes were validated in 20 paired independent samples.

Results

Our results showed that TP53 R249S was significantly associated with ADAMTS18 rs9930984 (adjustedP= 4.84×10−6), WDR49 rs75218075 (adjustedP= 7.36 × 10−5) and SLC8A3 rs8022091 (adjustedP= 0.042). Additionally, ADAMTS18 mRNA expression was significantly higher in HCC tissue, compared with paired non-tumor tissue (P= 0.041) and patients carrying the TT genotype at rs9930984 showed lower ADAMTS18 expression in non-tumor tissue, compared with those carrying the GT genotype (P= 0.0028).

Conclusions

TP53 expression is significantly associated with R249S mutation in HCC. Our collective results suggest that rs9930984, rs75218075 and rs8022091 are associated with susceptibility to the R249S mutation in cases of HCC exposed to AFB1 and HBV infection.
The impact of the COVID-19 lockdown on maternal mental health and coping in the UK: Data from the COVID-19 New Mum Study
Authors: Dib Sarah , Rougeaux Emeline , Vázquez Adriana , Wells Jonathan , Fewtrell Mary
Published: August 2020

Background

Depression and anxiety affect up to 20% of new and expectant mothers during the perinatal period; this rate may have increased due to COVID-19 and lockdown measures. This analysis aimed to assess how mothers are feeling and coping during lockdown, and to identify the potential pathways that can assist them.

Methods

1329 women living in the UK aged ≥18 years with an infant ≤12 months of age completed an anonymous online survey. Descriptive analysis of maternal mental health, coping, support received, activities undertaken and consequences of lockdown was conducted. Linear regression was used to predict maternal mental health and coping, using activities, support, and consequences of the lockdown as predictors, while adjusting for age, gestational age, ethnicity, income, marital status and number of children.

Results

More than half of the participants reported feeling down (56%), lonely (59%), irritable (62%) and worried (71%), to some or high extent since lockdown began. Despite this, 70% felt able to cope with the situation. Support with her own health (95% CI .004,235), contacting infant support groups (95% CI -.003, .252), and higher infant gestational age (95% CI .000, .063) predicted better mental health. Travelling for work (95% CI -.680, - .121), lockdown having a major impact on the ability to afford food (95% CI -1.202, -.177), and having an income lower than 30k (95% CI -.475, -.042) predicted poorer mental health. Support with her own health and more equal division of household chores were associated with better coping.

Conclusion

During lockdown, a large proportion of new mothers experienced symptoms of poor mental health; mothers of infants with lower gestational age, with low income, and who are travelling to work were particularly at risk. However, greater support for maternal health and with household chores showed positive associations with maternal mental health and coping. These findings highlight the urgent need to assess maternal mental health, and to identify prevention strategies for mothers during different stages of lockdown.
Fragrances' luxury brand extension: consumer behaviour and influences
Authors: Figueiredo Jose , Eiriz Vasco
Published: August 2020

Purpose

This article aims to understand the influences surrounding the consumption of fragrances, especially if these products fit as a brand extension of luxury brands. More specifically, it aims at identifying the main reasons behind the process of buying fragrances and the main features associated with the consumption of fragrances.

Design/methodology/approach

This research adopts a qualitative approach in the form of 15 in-depth interviews with consumers of fragrances, seeking to assess attitudes and influences in the consumption of fragrances as a brand extension of luxury brands.

Findings

This research shows that the emotional use of fragrances as a luxury product is much more important than their functionality, the relationship between the studied consumers and fragrances depends on the occasion of consumption (season of the year; day or night) and the aroma and the durability of the aroma is the main decision criterion for the purchase of fragrances. Respondents have also mentioned comfort, elegance and sophistication as attributes to choose a fragrance as a luxury product.

Originality/value

This article adds to the current knowledge on the topics of luxury brand management and buying behaviour by providing a better understanding of attitudes and influences towards the use of fragrances. This research recognizes the importance of a brand extension strategy for luxury brands, especially in the case of fragrances.
Role of social networking services for scientists in promoting scientific output on example of Polish representatives of social communication and media sciences
Authors: Kowalska-Chrzanowska Małgorzata , Krysiński Przemysław
Published: August 2020

Purpose

This paper aims to answer the question of how the Polish representatives of social communication and media sciences communicate the most recent scientific findings in the media space, i.e. what types of publications are shared, what activities do they exemplify (sharing information about their own publications, leading discussions, formulating opinions), what is the form of the scientific communication created by them (publication of reference lists' descriptions, full papers, preprints and post prints) and what is the audience reception (number of downloads, displays, comments).

Design/methodology/approach

The authors present the results of analysis conducted on the presence of the most recent (2017–2019) publications by the Polish representatives of the widely understood social communication and media sciences in three selected social networking services for scientists: ResearchGate, Google Scholar and Academia.edu. The analyses covered 100 selected representatives of the scientific environment (selected in interval sampling), assigned, according to the OECD classification “Field of Science”, in the “Ludzie nauki” (Men of Science) database to the “media and communication” discipline.

Findings

The conducted analyses prove a low usage level of the potential of three analysed services for scientists by the Polish representatives of social communication and media sciences. Although 60% of them feature profiles in at least one of the services, the rest are not present there at all. From the total of 113 identified scientists' profiles, as little as 65 feature publications from 2017 to 2019. Small number of alternative metrics established in them, implies, in turn, that if these metrics were to play an important role in evaluation of the value and influence of scientific publications, then this evaluation for the researched Polish representatives of social communication and media sciences would be unfavourable.

Originality/value

The small presence of the Polish representatives of the communication and media sciences in three analysed services shows that these services may be – for the time being – only support the processes of managing own scientific output. Maybe this quite a pessimistic image of scientists' activities in the analysed services is conditioned by a simple lack of the need to be present in electronic channels of scientific communication or the lack of trust to the analysed services, which, in turn, should be linked to their shortcomings and flaws. However, unequivocal confirmation of these hypotheses might be brought by explorations covering a larger group of scientists, and complemented with survey studies. Thus, this research may constitute merely a starting point for further explorations, including elaboration of good practices with respect to usage of social media by scientists.
Thermo-hydraulic and entropy generation analysis for magnetohydrodynamic pressure driven flow of nanofluid through an asymmetric wavy channel
Authors: Mehta Sumit Kumar , Pati Sukumar
Published: August 2020

Purpose

The purpose of this paper is to analyze the thermal, hydraulic and entropy generation characteristics for the magneto-hydrodynamic (MHD) pressure-driven flow of Al2O3-water nanofluid through an asymmetric wavy channel.

Design/methodology/approach

Galerkin finite element method is used to solve the governing transport equations numerically within the computational domain using the appropriate boundary conditions. The temperature and flow fields are computed by varying Reynolds number (Re), Hartmann number (Ha) and nano-particle volume fraction (ϕ) in the following range: 10 ≤ Re ≤ 500, 0 ≤ Ha ≤ 75 and 0 ≤ ϕ ≤ 5%.

Findings

The formation of the recirculation zones in the wavy passages, the size of it and the strength of the vortices formed can be modulated by the application of the magnetic field. The overall heat transfer rate increases with Ha for all ϕ both for a lower and higher regime of Re although the enhancement is more for lower values of Re and nanofluids as compared to base fluid and for intermediate values of Re, the effect of a magnetic field is almost insignificant. The magnetic performance factor (PFmagnetic) decreases with Ha although the rate of decrement varies with Re. The increase ϕ also enhances PFmagnetic especially at lower and higher values of Re. The addition of nano-particle enhances the entropy generation at lower values of the Re, while the opposite effect is seen for higher values of Re.

Practical implications

The present study has enormous practical relevance for the design of heat exchanger applied for solar collectors, process plants, textile and aerospace applications.

Originality/value

The combined effects on the heat transfer rate and the associated pressure drop penalty due to the applied magnetic field for the flow of nanofluid through an asymmetric wavy channel have not been reported to date. The effect of the magnetic field on the formation of recirculation zones and hot spot intensity in the asymmetric wavy channel has been examined in detail. The PFmagnetic is investigated first time for the MHD nanofluid flow through a wavy channel.
Openness, resource sharing and digitalization – an examination of the current trends in Finland
Authors: Saarti Jarmo , Tuominen Kimmo
Published: August 2020

Purpose

Although resource sharing between scholars is evolving rapidly, This paper uses paper-based interlibrary lending (ILL) procedures in the service repertoire of academic libraries. However, the current business model of acquiring toll-access journals and e-books does not seem to fit very well with traditional ILL practices. In addition, the new models of peer-to-peer resource sharing between academics seem to be much more effective than ILL. Scholars arrange access to the needed publications by using legal (buying, exchanging) and illegal means (Sci-Hub, etc.). Furthermore, the demands for open access have increased, voiced not only by librarians and science funders but also by politicians. This development might change the scholarly publication ecosystem, even though older publications are still likely to remain closed.

Design/methodology/approach

This paper contrasts the ILL and usage statistics of Finnish university libraries with the use of ResearchGate, a popular academic social network, which we treat as an example of a peer-to-peer sharing service.

Findings

Based on the data, there seems to be a change of paradigm in the resource sharing: the traditional ILL seems to be decreasing and becoming more like a niche service and the digital use and use of social media peer-to-peer resource sharing applications seem to increase rapidly.

Originality/value

The paper examines current resource sharing trends. The analysis is based on the data of Finnish resource sharing, interlibrary lending and ResearchGate usage.
A survey on national culture and corporate financial decisions: current status and future research
Authors: Kutan Ali , Laique Usama , Qureshi Fiza , Rehman Ijaz Ur , Shahzad Faisal
Published: August 2020

Purpose

The extant literature provides substantial evidence that various facets of national culture play a significant role in corporate financial decision making. We systematically review the role of national culture on the various thematic domains of corporate financial decision making to outline what have been studies thus far and what needs to be studied.

Design/methodology/approach

Keywords such as national culture, organizational culture, power distance, uncertainty avoidance, masculinity, risk aversion and individualism for a search in the prominent academic literature databases are used. The studies related to the corporate financial decision making that is tied with these keywords are identified and selected for the systematic review.

Findings

The review of extant literature suggests strong evidence that national culture has a significant role in influencing corporate cash holding, corporate risk-taking, individual behaviour of the financial managers and initial public offering by the corporations. The review also indicates, although extant studies have examined the role of national culture in the key corporate financial decisions, evidence on the role of national culture in the firm's investment efficiency aspects is rather scarce. Also, what explains the role of national culture in corporate financial decision making has not been empirically exploited through causal mechanisms.

Practical implications

The findings of the studies help advance our understanding of the current research status concerning the role played by the national culture in shaping corporate financial decisions and raise important future calls.

Originality/value

To best of our knowledge, no prior study has systematically reviewed the role of national culture in the thematic domains of corporate financial decision making.
Factors affecting the compactness of filter cake for diaphragm wall slurry
Authors: Fengjun Zhang , Cui Kong , Qianbao Chen
Published: August 2020

Purpose

The purpose of this paper is to explore the factors that affect the compactness of the mud filter cake, so as to prepare diaphragm wall slurry with good uniformity, small filtration loss and excellent recycling performance.

Design/methodology/approach

In this paper, the thickness, filtration loss and slurry viscosity of the filter cake are used as the characterization methods. The effects of pore depth, slurry specific gravity, intercalated metal ions, bridging polymer and water-soluble polymer on the compactness of the filter cake were studied.

Findings

The experimental results showed that the slurry's own pressure (pore depth) and specific gravity have little influence on the compactness of the filter cake and K+ can be considered as an auxiliary filtration loss reduction factor. Both the sulfonate copolymer and the potassium polyacrylate particle can significantly reduce the filtration loss of the slurry, which can effectively improve the filter cake compactness. Moreover, the composite application of potassium polyacrylate particles in the sizes of 80–100 and 150–200 meshes can exhibit a better filter cake compaction effect.

Originality/value

It solves the problems of high pulping cost, serious pollution of the environment, poor quality of filter cake formation and large filtration loss during the construction of the diaphragm wall, which improved the construction quality of the diaphragm wall.
Fabrication of a piezoelectrically driven micropositioning 3-DOF stage with elastic body using a multi-material 3D printer
Authors: Baek Sang-Woo , Cho Nahm-Gyoo , Lee Dong-Hyeok
Published: August 2020

Purpose

This paper aims to propose a method for manufacturing multi-material monolithic structures with flexible materials to construct the elastic body by using a dual-nozzle three-dimensional printer to develop a piezoelectric (PZT)-driven micropositioning stage with three degrees of freedom (3-DOF) and flexure hinges.

Design/methodology/approach

Polylactic acid (PLA) and nylon were used for the lever structure’s frame and flexure hinge, respectively. Additionally, the stage consisted of three PZT actuators for fine movement in the nanometer scale in 3-DOF (x, y and θ-directions). For the design of the stage, the kinematic analysis model and the finite element method (FEM) analysis was undertaken for comparing between PLA with nylon (multi-material), PLA (single material) and aluminum (conventional-material). In addition, two verification experiments were implemented for the fabricated prototype stage. First, to evaluate various assessments (lever ratio, hysteresis, coupling error and resolution), a measurement is carried out using the three capacitive sensors. Then, a two-camera-vision measurement experiment was performed to verify the displacement and lever ratio over the full-scale working range of the fabricated positioning stage, and the results from the experimentation and the FEM analysis were compared.

Findings

The authors confirmed enhancements in the properties of the lever structure frame, which requires stiffness and of the hinge, which requires flexibility for elastic deformation. Comparing FEM analysis and experimental results, although the performance as shown by experimental results was lower: the maximum difference being 3.4% within the end-point working range; this difference was sufficient to be a plausible alternative for the aluminum-based stage.

Originality/value

Multi-material monolithic-structure fabrication has an effective advantage in improving the performance of the stage, by using a combination of materials capable of reinforcing the desired characteristics in the necessary parts. It was verified that the fabricated stage can substitute the aluminum-based stage and can achieve a higher performance than single-material stages. Thus, precise-positioning stages can be manufactured in many kinds of structures with various properties and contribute to weight reduction and low costs for application equipment.
Embedding SMEs in national systems of innovation: Participant perceptions of Australia's CRC‐P program
Authors: Noble David , Charles Michael B. , Keast Robyn , Carlopio James
Published: August 2020

Governments throughout the world employ a variety of policy mechanisms to promote economy‐enhancing innovation, although the embedding of SMEs in national systems of innovation has generally proved problematic. The Australian Cooperative Research Centres – Projects Program represents a recent attempt to do precisely this. Interviews with participants in the first two rounds of the Program report high levels of satisfaction, but also highlight potential for friction between SMEs and research providers, together with the opportunity for strategic manipulation. This study provides government officials and other stakeholders with preliminary recommendations regarding where the Program is succeeding, and where further vigilance may be required.
Planning the supply of aged care services: It's time to talk denominators
Authors: Gibson Diane
Published: August 2020

Objectives

This paper explores how changes in demography, service use and the aged care system have implications for the appropriateness of the denominator in the aged care provision ratio.

Methods

Official statistics were analysed to create five alternative scenarios for residential care planning in a 2000‐2027 time series.

Results

The four age‐based denominators and a revised denominator incorporating age‐ and sex‐specific disability rates generated diverse levels of absolute supply. The 75+ denominator produced 1400 fewer beds than the 70+ denominator by 2018, but over 14 000 additional beds by 2027.

Conclusion

The 70+ based ratio developed almost forty years ago has served its purpose reasonably well. However, changes in the nature of the aged care system, different patterns of use by age and sex, and demographic changes suggest that long‐term aged care planning requires careful review in choosing a more robust version of the provision ratio for the future.