bluuebunny/crossref_metadata_2025 huggingface dataset:
Disentangling the genetic basis of rhizosphere microbiome assembly in tomato
Authors: Oyserman Ben O , Flores Stalin Sarango , Griffioen Thom , Pan Xinya , van der Wijk Elmar , Pronk Lotte , Lokhorst Wouter , Nurfikari Azkia , Stopnisek Nejc , Kupczok Anne , Cordovez Viviane , Carrión Víctor J , Ligterink Wilco , Snoek Basten L , Medema Marnix H , Raaijmakers Jos M
Published: December 2021

Microbiomes play a pivotal role in plant growth and health, but the genetic factors involved in microbiome assembly remain largely elusive. Here, 16S amplicon and metagenomic features of the rhizosphere microbiome were mapped as quantitative traits of a recombinant inbred line population of a cross between wild and domesticated tomato. Gene content analysis of prioritized tomato QTLs suggested a genetic basis for differential recruitment of various rhizobacterial lineages, including a Streptomyces-associated 6.31-Mbp region harboring tomato domestication sweeps and encoding, among others, the iron regulator FIT and the aquaporin SlTIP2.3. Within metagenome-assembled genomes of the rhizobacterial lineages Streptomyces and Cellvibrio, we identified microbial genes involved in metabolism of plant polysaccharides, iron, sulfur, trehalose, and vitamins, whose genetic variation associated with either modern or wild tomato QTLs. Integrating ‘microbiomics’ and quantitative plant genetics pinpointed putative plant and reciprocal microbial traits underlying microbiome assembly, thereby providing the first step towards plant-microbiome breeding programs.
Earbox, an open tool for high-throughput measurement of the spatial organization of maize ears and inference of novel traits
Authors: Oury V. , Leroux T. , Turc O. , Chapuis R. , Palaffre C. , Tardieu F. , Prado S. Alvarez , Welcker C. , Lacube S.
Published: December 2021

Background

Characterizing plant genetic resources and their response to the environment through accurate measurement of relevant traits is crucial to genetics and breeding. The spatial organization of the maize ear provides insights into the response of grain yield to environmental conditions. Current automated methods for phenotyping the maize ear do not capture these spatial features.

Results

We developed EARBOX, a low-cost, open-source system for automated phenotyping of maize ears. EARBOX integrates open-source technologies for both software and hardware that facilitate its deployment and improvement for specific research questions. The imaging platform consists of a customized box in which ears are repeatedly imaged as they rotate via motorized rollers. With deep learning based on convolutional neural networks, the image analysis algorithm uses a two-step procedure: ear-specific grain masks are first created and subsequently used to extract a range of trait data per ear, including ear shape and dimensions, the number of grains and their spatial organisation, and the distribution of grain dimensions along the ear. The reliability of each trait was validated against ground-truth data from manual measurements. Moreover, EARBOX derives novel traits, inaccessible through conventional methods, especially the distribution of grain dimensions along grain cohorts, relevant for ear morphogenesis, and the distribution of abortion frequency along the ear, relevant for plant response to stress, especially soil water deficit.

Conclusions

The proposed system provides robust and accurate measurements of maize ear traits including spatial features. Future developments include grain type and colour categorization. This method opens avenues for high-throughput genetic or functional studies in the context of plant adaptation to a changing environment.
DEAD-box RNA Helicases Act as Nucleotide Exchange Factors for Casein Kinase 2
Authors: Fatti Edoardo , Hirth Alexander , Švorinić Andrea , Günther Matthias , Cruciat Cristina-Maria , Stier Gunter , Acebron Sergio P. , Papageorgiou Dimitris , Sinning Irmgard , Krijgsveld Jeroen , Höfer Thomas , Niehrs Christof
Published: December 2021

DDX RNA helicases promote RNA processing but DDX3X is also known to activate casein kinase 1 ε (CK1ε). Here we show that not only is protein kinase stimulation a latent property of other DDX proteins towards CK1ε, but that this extends to casein kinase 2 (CK2α2) as well. CK2α2 enzymatic activity is stimulated by a variety of DDX proteins and we identify DDX1/24/41/54 as physiological activators required for full kinase activity in vitro and in Xenopus embryos. Mutational analysis of DDX3X reveals that CK1 and CK2 kinase stimulation engages its RNA binding-but not catalytic motifs. Mathematical modelling of enzyme kinetics and stopped-flow spectroscopy converge that DDX proteins function as nucleotide exchange factor towards CK2α2 that reduce unproductive reaction intermediates and substrate inhibition. Our study reveals protein kinase stimulation by nucleotide exchange as a new principle in kinase regulation and an evolved function of DDX proteins.
Visualizing pyrazinamide action by live single cell imaging of phagosome acidification and Mycobacterium tuberculosis pH homeostasis
Authors: Santucci Pierre , Aylan Beren , Botella Laure , Bernard Elliott M. , Bussi Claudio , Pellegrino Enrica , Athanasiadi Natalia , Gutierrez Maximiliano G.
Published: December 2021

The intracellular population of Mycobacterium tuberculosis (Mtb) is dynamically segregated within multiple subcellular niches with different biochemical and biophysical properties that, upon treatment, may impact antibiotic distribution, accumulation, and efficacy. However, it remains unclear whether fluctuating intracellular microenvironments alter mycobacterial homeostasis and contribute to antibiotic enrichment and efficacy. Here, we describe a dual-imaging approach that allows quantitative monitoring of host subcellular acidification and Mtb intrabacterial pH profiles by live-fluorescence microscopy in a biosafety level 3 laboratory. By combining this live imaging approach with pharmacological and genetic perturbations, we show that Mtb can maintain its intracellular pH independently of the surrounding pH in primary human macrophages. Importantly, we show that unlike bedaquiline (BDQ), isoniazid (INH) or rifampicin (RIF), the front-line drug pyrazinamide (PZA) displays antibacterial efficacy by acting as protonophore which disrupts intrabacterial pH homeostasis in cellulo. By using Mtb mutants with different intra-macrophage localisation, we confirmed that intracellular acidification is a prerequisite for PZA efficacy in cellulo. We anticipate this dual imaging approach will be useful to identify host cellular environments that affect antibiotic efficacy against intracellular pathogens.

Highlights

Mtb maintains its intrabacterial pH inside both acidic and neutral subcellular microenvironments of human macrophages

Pyrazinamide, but not other frontline antibiotics, acts as a protonophore in cellulo

Pyrazinamide-mediated intrabacterial pH homeostasis disruption and antibacterial efficacy requires host endolysosomal acidification

Cytosolic localisation mediated by ESX-1 contributes to pyrazinamide antibacterial activity resistance

Pyrazinamide conversion into pyrazinoic acid by the pyrazinamidase/nicotinamidase PncA is essential for its protonophore activity and efficacy in cellulo
Structure of a TRAPPII-Rab11 activation intermediate reveals GTPase substrate selection mechanisms
Authors: Bagde Saket R. , Fromme J. Christopher
Published: December 2021

Rab1 and Rab11 are essential regulators of the eukaryotic secretory and endocytic recycling pathways. The TRAPP complexes activate these GTPases via nucleotide exchange using a shared set of core subunits. The basal specificity of the TRAPP core is towards Rab1, yet the TRAPPII complex is specific for Rab11. A steric gating mechanism has been proposed to explain TRAPPII counterselection against Rab1. Here we present cryoEM structures of the 22-subunit TRAPPII complex from budding yeast, including a TRAPPII-Rab11 nucleotide exchange intermediate. The Trs130 subunit provides a “leg” that positions the active site distal to the membrane surface, and this leg is required for steric gating. The related TRAPPIII complex is unable to activate Rab11 due to a repulsive interaction, which TRAPPII surmounts using the Trs120 subunit as a “lid” to enclose the active site. TRAPPII also adopts an open conformation enabling Rab11 to access and exit from the active site chamber.
Antiviral RNAi response against the insect-specific Agua Salud alphavirus
Authors: Altinli Mine , Leggewie Mayke , Badusche Marlis , Gyanwali Rashwita , Scherer Christina , Schulze Jonny , Sreenu Vattipally B. , Fegebank Marvin , Zibrat Bernhard , Fuss Janina , Junglen Sandra , Schnettler Esther
Published: December 2021

Arboviruses transmitted by mosquitoes are responsible for the death of millions of people each year. In addition to arboviruses, many insect-specific viruses (ISVs) have been discovered in mosquitoes in the last decade. ISVs, in contrast to arboviruses transmitted by mosquitoes to vertebrates, cannot replicate in vertebrate cells even when they are evolutionarily closely related to arboviruses. The alphavirus genus includes many arboviruses, although only a few ISVs have been discovered from this genus so far. Here, we investigate the interactions of a recently isolated insect-specific alphavirus, Agua-Salud alphavirus (ASALV), with its mosquito host.

RNAi is one of the essential antiviral responses against arboviruses, although there is little knowledge on the interactions of RNAi with ISVs. Through knock-down of transcripts of the different key RNAi pathway (siRNA, miRNA and piRNA) proteins, we show the antiviral role of Ago2 (siRNA), Ago1 (miRNA), and Piwi4 proteins against ASALV in Aedes aegypti derived cells. ASALV replication increased in Dicer2 and Ago2 knock-out cells, confirming the antiviral role of the siRNA pathway. In infected cells, mainly ASALV-specific siRNAs are produced while piRNAs, with the characteristic nucleotide bias resulting from ping-pong amplification, are only produced in Dicer2 knock-out cells. Taken together, ASALV interactions with the mosquito RNAi response differs from arthropod-borne alphaviruses in some aspects, although they also share some commonalities. Further research is needed to understand whether the identified differences can be generalised to other insect-specific alphaviruses.
Extracellular Matrix protein gelatin provides higher expansion, reduces size heterogeneity, and maintains cell stiffness in a long-term culture of mesenchymal stem cells
Authors: Mogha Pankaj , Iyer Shruti , Majumder Abhijit
Published: December 2021

Extracellular matrices (ECM) present in our tissues play a significant role in maintaining tissue homeostasis through various physical and chemical cues such as topology, stiffness, and secretion of biochemicals. They are known to influence the behaviour of resident stem cells. It is also known that ECM type and coating density on cell culture plates strongly influence in vitro cellular behaviour. However, the influence of ECM protein coating on long term mesenchymal stem cell expansion has not been studied yet. To address this gap, we cultured bone-marrow derived hMSCs for multiple passages on the tissue culture plastic plates coated with 25 μg/ml of various ECM proteins. We found that cells on plates coated with ECM proteins had much higher proliferation compared to the regular tissue culture plates. Further, gelatin coated plates helped the cells to grow faster compared to collagen, fibronectin, and laminin coated plates. Additionally, the use of Gelatin showed less size heterogeneity among the cells when expanded from passages P3 to P9. Gelatin also helped in maintaining cellular stiffness which was not observed across other ECM proteins. In summary, in this research, we have shown that gelatin which is the least expensive compared to other ECM proteins provides a better platform for mesenchymal stem cell expansion.
Transcriptional and post-transcriptional regulation of young genes in plants
Authors: Raxwal Vivek Kumar , Singh Somya , Agarwal Manu , Riha Karel
Published: December 2021

New genes continuously emerge from non-coding DNA or by diverging from existing genes, but most of them are rapidly lost and only a few become fixed within the population. We hypothesized that young genes are subject to transcriptional and post-transcriptional regulation to limit their expression and minimize their exposure to purifying selection. We found that young genes in rice have relatively low expression levels, which can be attributed to distal enhancers, and closed chromatin conformation at their transcription start sites (TSS). The chromatin in TSS regions can be re-modeled in response to abiotic stress, indicating conditional expression of young genes. Furthermore, transcripts of young genes in Arabidopsis tend to be targeted by nonsense-mediated RNA decay, presenting another layer of regulation limiting their expression. Together, these data suggest that transcriptional and post-transcriptional mechanisms contribute to the conditional expression of young genes, which may alleviate purging selection while providing an opportunity for phenotypic exposure and functionalization.
Structure and mechanism of NALCN-FAM155A-UNC79-UNC80 channel complex
Authors: Kang Yunlu , Chen Lei
Published: December 2021

NALCN channel mediates sodium leak currents and is important for maintaining proper resting membrane potential. NALCN and FAM155A form the core complex of the channel, the activity of which essentially depends on the presence of both UNC79 and UNC80, two auxiliary proteins. NALCN, FAM155A, UNC79, and UNC80 co-assemble into a large hetero-tetrameric channel complex. Genetic mutations of NALCN channel components lead to neurodevelopmental diseases. However, the structure and mechanism of the intact channel complex remain elusive. Here, we present the cryo-EM structure of the mammalian NALCN-FAM155A-UNC79-UNC80 quaternary complex. The structure showed that UNC79-UNC80 form a large piler-shaped heterodimer which was tethered to the intracellular side of the NALCN channel through tripartite interactions with the cytoplasmic loops of NALCN. Two interactions are essential for proper cell surface localization of NALCN. The other interaction relieves the self-inhibition of NALCN by pulling the auto-inhibitory CTD Interacting Helix (CIH) out of its binding site.
Influence of Pink Pigmented Facultative methylotrophic bacteria (PPFM) as a foliar spraying on the growth and productivity of strawberry (Fragaria xananassa Duch.)
Authors: Ismail Shadia A. , Fafy A.M.
Published: December 2021

Pink pigmented facultative methylotrophic bacterium (PPFM) has a favorable impact on plant development and production, it is known as a biostimulator, biofertilizer and biocontroller. Here we investigate the effect of foliar spraying of PPFM, 10% methanol,30% methanol, and their combinations on the growth, fruit quality, and yield of two strawberry cultivars. PPFM was isolated from cotton leaves using imprinting technique. 16S rRNA sequence analysis identified it to be Methylobacterium radiotolerance. Its 16S rRNA sequence were deposited in the Gene Bank under accession number MT644122.1. Two field experiments were conducted during the 2017/2018 and 2018/2019 seasons to investigate the effect of foliar spraying of PPFM and methanol (10 and 30%) on the growth, fruit quality, and yield of two strawberry cultivars. The obtained results showed that, there were no significant differences in the most characteristics between the two cultivars except foliage fresh weight and early yield were higher in cv. Florid, however, Festival cv. recorded higher total yield /plant, anthocyanins and ascorbic acid content in both seasons. Spraying PPFM exhibited the highest values of chlorophyll, fresh weight, total yield and quality. Furthermore, PPFM combined with methanol 10% gave the highest values of leaf area, dry matter %, early yield and some fruit quality. Spraying cv. Florida with PPFM resulted in the best interactions for early yield. However, the best interaction for total yield and most fruit quality features was observed with Festival c.v. and spraying PPFM. It is reasonable to conclude that PPFM is the most effective treatment, increasing strawberry total yield/fed by 28.1 % in the 1st season and 27.91 % in the 2nd season compared to the control.
Insilico and Invitro optimization of Naringin and rutin molecules targeting DNA damage in breast cancer cells
Authors: Pravin Badhe , Nanaware Vivek , Ashwini Badhe
Published: December 2021

Discovering the molecular mechanisms of DNA damage response pathways has led to new therapeutic approaches in oncology. Our study optimized DNA damage-targeting molecules naringin and rutin in breast cancer cells.

Our study involved MTT assays for detection of its toxicity and proliferative activity in breast cancer cells and normal cancer cells. Our studies determined the molecules’ antioxidant properties using the DPPH assay. The role in reducing free radicals has been evaluated using a variety of free radical scavenging activity assays.

Further evaluation of the molecules was carried out by high alkaline comet assay (pH >13) to test for genotoxicity. Human Dermal Fibroblast cells (2DD) (1×105 cells/ml) and breast cancer cells (MDA-MB-231) were pre-incubated with Naringin and Rutin (10 µM) for one hour.

In normal cells, rutin and naringin molecules do not cause genotoxicity, but they cause DNA damage in breast cancer cells when they are diluted to 10µM. The results from our study indicate that both molecules cause 60-70% DNA damage in breast cancer cells.
Interaction of Th(IV), Pu(IV) and Fe(III) with ferritin protein: how similar?
Authors: Zurita Cyril , Tsushima Satoru , Solari Pier Lorenzo , Jeanson Aurélie , Creff Gaëlle , Den Auwer Christophe
Published: December 2021

Ferritin is the main protein of Fe storage in eukaryote and prokaryote cells. It is a large multifunctional, multi-subunit protein consisting of heavy H and light L subunits. In the field of nuclear toxicology, it has been suggested that some actinide elements, such as thorium and plutonium at oxidation state +IV, have a comparable `biochemistry' to iron at oxidation state +III owing to their very high tendency for hydrolysis and somewhat comparable ionic radii. Therefore, the possible mechanisms of interaction of such actinide elements with the Fe storage protein is a fundamental question of bio-actinidic chemistry. We recently described the complexation of Pu(IV) and Th(IV) with horse spleen ferritin (composed mainly of L subunits). In this article, we bring another viewpoint to this question by further combining modeling with our previous EXAFS data for Pu(IV) and Th(IV). As a result, the interaction between the L subunits and both actinides appears to be non-specific but driven only by the density of the presence of Asp and Glu residues on the protein shell. The formation of an oxyhydroxide Th or Pu core has not been observed under the experimental conditions here, nor the interaction of Th or Pu with the ferric oxyhydroxide core.
The CirPAD, a circular 1.4 M hybrid pixel detector dedicated to X-ray diffraction measurements at Synchrotron SOLEIL
Authors: Desjardins Kewin , Mocuta Cristian , Dawiec Arkadiusz , Réguer Solenn , Joly Philippe , Dubuisson Jean-Michel , Alves Filipe , Noureddine Arafat , Bompard Frédéric , Thiaudière Dominique
Published: December 2021

One of the challenges of all synchrotron facilities is to offer the highest performance detectors for all their specific experiments, in particular for X-ray diffraction imaging and its high throughput data collection. In that context, the DiffAbs beamline, the Detectors and the Design and Engineering groups at Synchrotron SOLEIL, in collaboration with ImXPAD and Cegitek companies, have developed an original and unique detector with a circular shape. This detector is based on the hybrid pixel photon-counting technology and consists of the specific assembly of 20 hybrid pixel array detector (XPAD) modules. This article aims to demonstrate the main characteristics of the CirPAD (for Circular Pixel Array Detector) and its performance – i.e. excellent pixel quality, flat-field correction, high-count-rate performance, etc. Additionally, the powder X-ray diffraction pattern of an LaB6 reference sample is presented and refined. The obtained results demonstrate the high quality of the data recorded from the CirPAD, which allows the proposal of its use to all scientific communities interested in performing experiments at the DiffAbs beamline.
Asymmetric and threshold effects of public debt on economic growth in SADC: a panel smooth transition regression analysis
Authors: Makhoba Bongumusa Prince , Kaseeram Irrshad , Greyling Lorraine
Published: December 2021

Purpose

This study aims to interrogate dynamic asymmetric relationships between public debt and economic growth in Southern African Developing Communities (SADC), over the period 2000–2018.

Design/methodology/approach

The study employed a panel smooth transition regression (PSTR) technique to analyse dynamic asymmetric relationships between public debt and economic growth, and the threshold effect at which public debt hampers economic growth.

Findings

The findings indicate that there is a significant nonlinear effect of debt on economic growth in SADC. The study discovered a debt threshold of 60% to GDP at which debt beyond this threshold deteriorates long-term growth. The low-debt regime was found to be positive and statistically significant, while the high-debt regime is detrimental for long-term growth. Fiscal policymakers ought to consider the adoption of well-coordinated debt policies that aims to strike a balance between sustainable public debt and economic growth, within a reasonable threshold target.

Originality/value

The study focusses on asymmetric and threshold analysis of public debt on economic growth in SADC using sophisticated panel smooth transition regression (STAR). This study provides rigorous empirical evidence within the SADC perspective in which previous studies have predominantly been confined in advanced economies.
“Is there anybody out there?” Using a telepresence robot to engage in face time at the office
Authors: Muratbekova-Touron Maral , Leon Emmanuelle
Published: December 2021

Purpose

The purpose of this paper is to study the impact of mobile robotic telepresence systems on face time – which refers to people “seeing and being seen” – and analyse whether they allow overcoming the challenges associated with telecommuting.

Design/methodology/approach

This research is based on a qualitative methodology in two French high-tech companies using interviews to better understand how the use of a telepresence robot is experienced by teleworkers, co-workers and their managers.

Findings

The results demonstrate that telepresence robots do offset the absence of teleworkers by allowing them to engage in face time, even remotely. It shows how the telepresence robot's affordances impact the different dimensions of face time and examine the processes through which teleworkers and co-workers anthropomorphize the robot and manage their privacy needs.

Originality/value

This article further elaborates the concept of face time and offers six dimensions to study in a digitally driven environment, including two newly identified dimensions. It also discusses the surveillance and privacy needs issues raised by the use of mobile robotic telepresence (MRP) systems.
Saturation, acceleration and information pathologies: the conditions that influence the emergence of information literacy safeguarding practice in COVID-19-environments
Authors: Lloyd Annemaree , Hicks Alison
Published: December 2021

Purpose

The purpose of this second study into information literacy practice during the COVID-19 pandemic is to identify the conditions that influence the emergence of information literacy as a safeguarding practice.

Design/methodology/approach

The qualitative research design comprised one to one in-depth interviews conducted virtually during the UK's second and third lockdown phase between November 2020 and February 2021. Data were coded and analysed by the researchers using constant comparative techniques.

Findings

Continual exposure to information creates the “noisy” conditions that lead to saturation and the potential for “information pathologies” to act as a form of resistance. Participants alter their information practices by actively avoiding and resisting formal and informal sources of information. These reactive activities have implications for standard information literacy empowerment discourses.

Research limitations/implications

The paper is limited to the UK context.

Practical implications

Findings will be useful for librarians and researchers who are interested in the theorisation of information literacy as well as public health and information professionals tasked with designing long-term health promotion strategies.

Social implications

This paper contributes to our understandings of the role that information literacy practices play within ongoing and long-term crises.

Originality/value

This paper develops research into the role of information literacy practice in times of crises and extends understanding related to the concept of empowerment, which forms a central idea within information literacy discourse.
Body shapes and apparel fit for overweight and obese women in the US: the implications of current sizing system
Authors: Shin Eonyou , Saeidi Elahe
Published: December 2021

Purpose

The purpose of this study was to categorize the whole body shapes of overweight and obese females in the US and examine apparel fit based on the current ASTM sizing standards related to the body shapes categorized.

Design/methodology/approach

Body scan data from 2,672 subjects were used. To categorize their whole body shapes using 97 body measurements, principal component analysis with varimax rotation, a hierarchical cluster analysis and K-means cluster analysis were used. To compare the ASTM sizing standards for plus sizes (curvy and straight) and missy sizes (curvy and straight), five body parts (bust, under bust, waist, top hip, hip) using the formula for fit tolerance (measurement plus half of the interval) were compared with the ASTM sizing standards to determine the size appropriate for each body part.

Findings

Five whole body shapes among overweight and obese females in the US were categorized: Rectangle-curvy; parallelogram-moderately curvy; parallelogram-hip tilt; inverted trapezoid-moderately curvy and inverted trapezoid-hip tilt. When the body measurements in each body shape were compared with the current ASTM sizing systems for both misses and plus sizes, four-fifths or more of overweight and obese female adults in the US would find it difficult to obtain a perfect fit for both tops and bottoms.

Originality/value

Identifying whole body shapes among overweight and obese women in the US contributes significantly, as it will help apparel companies that target the markets of larger women develop a new sizing system. This study is the first attempt to analyze fit by comparing the ASTM sizing charts with body measurements in each body shape group. Further, the study contributes to the body-related literature by filling gaps in missing whole BS categories among overweight and obese females.
Boundary work in value co-creation practices: the mediating role of cognitive assistants
Authors: Mele Cristina , Russo-Spena Tiziana , Marzullo MariaLuisa , Ruggiero Andrea
Published: December 2021

Purpose

How to improve healthcare for the ageing population is attracting academia attention. Emerging technologies (i.e. robots and intelligent agents) look relevant. This paper aims to analyze the role of cognitive assistants as boundary objects in value co-creation practices. We include the perceptions of the main actors – patients, (in)formal caregivers, healthcare professionals – for a fuller network perspective to understand the potential overlap between boundary work and value co-creation practices.

Design/methodology/approach

We adopted a grounded approach to gain a contextual understanding design to effectively interpret context and meanings related to human–robot interactions. The study context concerns 21 health solutions that had embedded the Watson cognitive platform and its adoption by the youngest cohort (50–64-year-olds) of the ageing population.

Findings

The cognitive assistant acts as a boundary object by bridging actors, resources and activities. It enacts the boundary work of actors (both ageing and professional, caregivers, families) consisting of four main actions (automated dialoguing, augmented sharing, connected learning and multilayered trusting) that elicit two ageing value co-creation practices: empowering ageing actors in medical care and engaging ageing actors in a healthy lifestyle.

Originality/value

We frame the role of cognitive assistants as boundary objects enabling the boundary work of ageing actors for value co-creation. A cognitive assistant is an “object of activity” that mediates in actors' boundary work by offering novel resource interfaces and widening resource access and resourceness. The boundary work of ageing actors lies in a smarter resource integration that yields broader applications for augmented agency.
Integrating relational systems theory with ethical leadership: how ethical leadership relates to employee turnover intentions
Authors: Marquardt Dennis J. , Manegold Jennifer , Brown Lee W.
Published: December 2021

Purpose

As ethical leadership has advanced as a construct, the degree to which healthy relational systems explain its effect on employee outcomes has been understudied. With this manuscript we conceptualize and test a model based on a Relational Systems approach to ethical leadership and its relationship with conflict and turnover intentions.

Design/methodology/approach

Two studies were conducted to test our hypothesized first- and second-stage moderated mediation model. In Study 1, online surveys were completed by 168 working adults across two different time points. Study 2 extended Study 1 by surveying 115 working adults across three time points using the Mechanical Turk platform.

Findings

The indirect relationship between ethical leadership and turnover intentions via relationship conflict was conditional based on follower moral identity. The negative influence of ethical leadership on relationship conflict and, in turn, turnover intentions was stronger for followers who had higher moral identities. In addition, our findings suggest that leader holding behaviors strengthen the negative indirect effects of ethical leadership on turnover intentions.

Originality/value

This paper demonstrates the usefulness of a Relational Systems theoretical approach to understanding ethical leadership. Specifically, ethical leaders, through their desire and ability to help employees feel known and not alone at work, are better able to reduce relationship conflict and, in turn, reduce employees' desire to leave the organization.
Decreased microRNA‐126 expression in psoriatic CD4+ T cells promotes T‐helper 17 cell differentiation and the formation of dermatitis in imiquimod‐induced psoriasis‐like mice
Authors: Wu Ruifang , Li Xin , Li Siying , Tang Guishao , Zhang Suhan , Zhu Yanshan , Zhang Xiaochao , Deng Min , Tan Siqi , Luo Shuangyan , Zhang Qing , Zhao Ming , Zhang Peng , Su Yuwen
Published: December 2021

Psoriasis is a chronic inflammatory skin disease with multiple genetic backgrounds, whose etiology and pathogenesis are still unclear. Complex T‐cell immune imbalance has been demonstrated to play an important role in pathogenesis of psoriasis. This study reported that microRNA‐126 (miR‐126) expression was decreased in CD4+ T cells of both psoriasis patients and psoriasis‐like mouse models and its expression was negatively correlated with the Psoriasis Area and Severity Index (PASI) score of psoriasis patients. Conditional Mir126 knockout in mouse CD4+ T cells can obviously aggravate the psoriasis‐like dermatitis and promote T‐helper (Th)1 and Th17 cells’ infiltration in spleen of imiquimod (IMQ)‐induced psoriasis‐like mouse model. In addition, the mRNA expression of Il17a and Il17f were significantly increased in mouse naïve CD4+ T cells with Mir126 knockout after stimulating with CD3 and CD28. Compared with naïve CD4+ T cells, the expression of Mir126 was decreased in Th17 cells, and Mir126 knockout notably promoted the differentiation of naïve CD4+ T cells to Th17 cells as well as the mRNA expression of Il17a, Il17f, Rorc, and Il23R. Our results revealed that decreased miR‐126 in psoriatic CD4+ T cells might accelerate the formation of skin lesions through promoting the differentiation of Th17 cells, thus suggesting a potential intervention target for psoriasis.
CARD‐FISH and prey tracer techniques reveal the role of overlooked flagellate groups as major bacterivores in freshwater hypertrophic shallow lakes
Authors: Šimek Karel , Mukherjee Indranil , Nedoma Jiří , de Paula Caio César Pires , Jezberová Jitka , Sirová Dagmara , Vrba Jaroslav
Published: December 2021

Heterotrophic nanoflagellates (HNF) and ciliates are major protistan planktonic bacterivores. The term HNF, however, describes a functional guild only and, in contrast to the morphologically distinguishable ciliates, does not reflect the phylogenetic diversity of flagellates in aquatic ecosystems. Associating a function with taxonomic affiliation of key flagellate taxa is currently a major task in microbial ecology. We investigated seasonal changes in the HNF and ciliate community composition as well as taxa‐specific bacterivory in four hypertrophic freshwater lakes. Taxa‐specific catalyzed reporter deposition‐fluorescence in situ hybridization probes assigned taxonomic affiliations to 51%–96% (average ±SD, 75 ± 14%) of total HNF. Ingestion rates of fluorescently labelled bacteria unveiled that HNF contributed to total protist‐induced bacterial mortality rates more (56%) than ciliates (44%). Surprisingly, major HNF bacterivores were aplastidic cryptophytes and their Cry1 lineage, comprising on average 53% and 24% of total HNF abundance and 67% and 21% of total HNF bacterivory respectively. Kinetoplastea were important consumers of bacteria during summer phytoplankton blooms, reaching 38% of total HNF. Katablepharidacea (7.5% of total HNF) comprised mainly omnivores, with changing contributions of bacterivorous and algivorous phylotypes. Our results show that aplastidic cryptophytes, accompanied by small omnivorous ciliate genera Halteria/Pelagohalteria, are the major protistan bacterivores in hypertrophic freshwaters.
The economic impact of the COVID‐19 pandemic on the Taiwanese food industry: Empirical evidence using business transaction data
Authors: Yang Feng‐An , Chang Hung‐Hao , Wang Jiun‐Hao
Published: December 2021

A rapidly growing literature examines the impacts of COVID‐19 on consumer spending and business operations. However, little is yet known about its effects on the food industry. We contribute to this topic by quantifying the effects of COVID‐19 on the Taiwanese food industry, including food manufacturing, wholesale, retail and service sectors. Using administrative data on the business transactions of food industry firms in Taiwan with a difference‐in‐differences model, we find that COVID‐19 reduced the total sales value of the food industry by 24%. However, the negative effects are unequally distributed among different sectors of the food industry. The negative effect is more pronounced in the food manufacturing sector. We also find a substantial impact in urban areas, high‐income areas and areas with a larger proportion of elderly population. Compared to most of the countries that implemented mandatory lockdowns to cope with COVID‐19, Taiwan maintained good control over the pandemic in 2020. The mobility of Taiwanese residents is much higher than those of other countries with severe infection rates. However, we show that there are still significant economic impacts on the food industry in Taiwan.
The Cumulative Role of Impoundments in Streamflow Alteration
Authors: Brogan Connor , Burgholzer Robert , Keys Tyler , Kleiner Joseph , Shortridge Julie , Scott Durelle
Published: December 2021

Small impoundments are numerous throughout river corridors. Limited data on their size and outflow have made it difficult to assess how these smaller impoundments cumulatively impact streamflow. This study combined rainfall‐runoff data from the Chesapeake Bay Watershed Model with a routing framework to develop a hydrologic model capable of analyzing flow alteration induced by cumulative impoundment. Using standard design processes and satellite imagery, simulations of impoundment hydraulics were assembled for both small and large impoundments. Eleven of the 170 impoundments in the Difficult Run watershed were modeled to assess their cumulative impact on downstream flow from 1984 to 2005. Multiple simulations were analyzed to determine incremental effects. We found that flow alteration increased with impoundment density. Impoundments prolonged storm hydrographs, increasing median and baseflows, and decreasing peak streamflow downstream. Impoundment size and location impacted downstream flow alteration as headwater channels ran dry and evaporation from impoundments with high surface area to storage ratios decreased extreme low flows. Large reservoirs had a greater impact on median flows, as small ponds dominated low flow alteration. Including a greater fraction of the watershed’s 170 small impoundments may further increase flow alteration. These results suggest that small impoundments play a large role in determining water availability, particularly during droughts.
Exercise can restore behavioural and molecular changes of intergenerational morphine effects
Authors: Sadat‐Shirazi Mitra‐Sadat , Nouri Zadeh‐Tehrani Setareh , Akbarabadi Ardeshir , Mokri Azarakhsh , Taleb Zadeh Kasgari Bahar , Zarrindast Mohammad‐Reza
Published: December 2021

In our previous studies, the offspring of morphine‐exposed parents (MEO) showed pharmacological tolerance to the morphine's reinforcing effect. According to the role of exercise in treatment of morphine addiction, the current study was designed to utilize exercise to improve the effect of parental morphine exposure on the morphine's reinforcing effect. Male and female rats received morphine for 10 days and were drug‐free for another 10 days. Each morphine‐exposed animal was allowed to mate either with a drug‐naïve or a morphine‐exposed rat. The offspring were divided into two groups: (1) offspring that were subjected to treadmill exercise and (2) offspring that were not subjected to exercise. The reinforcing effect of morphine was evaluated using conditioned place preference (CPP) and two‐bottle choice (TBC) tests. Levels of dopamine receptors (D1DR and D2DR), μ‐opioid receptor (MOR), and ΔFosB were evaluated in the nucleus accumbens. The MEO obtained lower preference scores in CPP and consumed morphine more than the control group in TBC. After 3 weeks of exercise, the reinforcing effect of morphine in the MEO was similar to the control. D1DR, D2DR, and MOR were increased in MEO compared with the controls before exercise. Levels of D1DR and MOR were decreased after exercise in the MEO; however, D1DR was increased in control. D2DR level did not change after exercise in MEO, but it increased in control group. Moreover, the level of ΔFosB was decreased among MEO while it was increased after exercise. In conclusion, exercise might modulate the reinforcing effect of morphine via alteration in levels of D1DR, MOR, and ΔFosB.
Effect of glycolic acid and EDTA on dentin mechanical properties
Authors: de Andrade Marafiga Fernanda , Barbosa Ana Flávia Almeida , Silva Emmanuel João Nogueira Leal , Souza Matheus Albino , Farina Ana Paula , Cecchin Doglas
Published: December 2021

The aim of this study was to evaluate the effect of glycolic acid (GA) and EDTA on dentin mechanical properties. For the cohesive strength, flexural strength and fracture strength tests, the hourglass of root dentin, dentin sticks and roots standardised to 1 mm thickness were used respectively. ANOVA and Tukey tests were used for statistical analysis (P < 0.05). The results showed that EDTA and GA 17% reduced the cohesive strength values when compared to distilled water (control; P = 0.0022 and P = 0.0016 respectively), whereas the values for GA 10% group were similar to those of the control group (P = 0.093). No statistically significant difference was found among the groups for the flexural strength test (P = 0.1974). Fracture strength test showed that EDTA and GA 17% were statistically similar to each other (P = 0.7694) and statistically inferior to GA 10% (P = 0.0007 and P = 0.0004 respectively). It was concluded that 10% GA showed fewer negative effects on dentin mechanical properties.
Clomiphene citrate for men with hypogonadism: a systematic review and meta‐analysis
Authors: Huijben Manou , Lock M. Tycho W.T. , de Kemp Vincent F. , de Kort Laetitia M.O. , van Breda H.M.K
Published: December 2021

Background

Male hypogonadism is a clinical and biochemical androgen insufficiency syndrome, becoming more prevalent with age. Exogenous testosterone is first‐choice therapy, with several side effects, including negative feedback of the hypothalamic–pituitary–gonadal axis, resulting in suppression of intratesticular testosterone production and spermatogenesis. To preserve these testicular functions while treating male hypogonadism, clomiphene citrate is used as off‐label therapy. This systematic review and meta‐analysis aimed to evaluate the effectiveness and safety of clomiphene citrate therapy for men with hypogonadism.

Methods

The EMBASE, PubMed, Cochrane databases were searched in May 2021, for effectiveness studies of men with hypogonadism treated with clomiphene citrate. Both intervention and observational studies were included. The Effective Public Health Practice Project Quality Assessment Tool, a validated instrument, was used to assess methodological study quality. The primary outcome measure was the evaluation of serum hormone concentration. Secondary outcomes were symptoms of hypogonadism, metabolic and lipid profile, side effects, safety aspects.

Results

We included 19 studies, comprising four randomized controlled trials and 15 observational studies, resulting in 1642 patients. Seventeen studies were included in the meta‐analysis, with a total of 1279 patients. Therapy and follow‐up duration varied between one and a half and 52 months. Total testosterone increased with 2.60 (95% CI 1.82–3.38) during clomiphene citrate treatment. An increase was also seen in free testosterone, luteinizing hormone, follicle stimulating hormone, sex hormone‐binding globulin and estradiol. Different symptom scoring methods were used in the included studies. The most frequently used instrument was the Androgen Deficiency in Aging Males questionnaire, whose improved during treatment. Reported side effects were only prevalent in less than 10% of the study populations and no serious adverse events were reported.

Conclusion

Clomiphene citrate is an effective therapy for improving both biochemical as well as clinical symptoms of males suffering from hypogonadism. Clomiphene citrate has few reported side effects and good safety aspects.
Psychological burden and coping in destination therapy patients with a left ventricular assist device: A qualitative content analysis
Authors: Levelink Michael , Reinhold Anna Katharina , Dewald Oliver , Brütt Anna Levke
Published: December 2021

Background

Due to an increasing prevalence of heart failure and persistent shortage of donor hearts, the number of left ventricular assist device (LVAD) implantations is growing. As more patients live with LVADs for prolonged periods of time, psychosocial outcomes are becoming more relevant. This particularly applies to destination therapy (DT) patients, who live with the LVAD for the rest of their lives.

Methods

We used a cross‐sectional qualitative design to explore psychological burden, coping strategies, and resources from the perspective of DT patients. Data were collected via semi‐structured in‐depth interviews with 18 patients who lived with the LVAD for 3 months to over 10 years. These were analyzed using an inductive content analysis. Due to the COVID‐19 pandemic, changes to the recruitment strategy and data collection strategies of the original study protocol were applied. Patients and clinicians were involved throughout the research process to ensure the validity of the results and implications.

Results

We synthesized 10 psychosocial, health, and treatment‐related burdens and identified 15 problem‐ and emotion‐focused coping strategies and 5 personal and environmental resources patients used to cope with the burden.

Conclusions

The findings provide deeper insights into the complex and specific situation of LVAD patients to better address the patient situation in health care and promote positive psychosocial outcomes. So far, health care practice and quality vary significantly between clinics due to individual treatment protocols. Our results highlight the need to improve medical and psychosocial care. Overarching care concepts may be developed based on the implications.
Organizations and efficiency in public services: The case of English lighthouses revisited
Authors: Bogart Dan , Dunn Oliver Buxton , Alvarez‐Palau Eduard J. , Shaw‐Taylor Leigh
Published: December 2021

Foundational debates about public service provision originate with the study of private lighthouses in England and Wales. We provide a new empirical assessment of cost and technical efficiency of competing lighthouse organizations in the early 1800s. Those with more private control charged ships higher fees and had greater operating costs. Lights with more local representation and funding provided lights of more local use and were most cheaply maintained. Our results help explain why government promoted nonprofit organizations to run lighthouses over private operators. We provide new insights into the role of private enterprise and nonprofit organizations in public service provision.
Roles of cutaneous cell‐cell communication in wound healing outcome: An emphasis on keratinocyte‐fibroblast crosstalk
Authors: Amiri Nafise , Golin Andrew P. , Jalili Reza B. , Ghahary Aziz
Published: December 2021

Tissue repair is a very complex event and involves a continuously orchestrated sequence of signals and responses from platelets, fibroblasts, epithelial, endothelial and immune cells. The details of interaction between these signals, which are mainly growth factors and cytokines, have been widely discussed. However, it is still not clear how activated cells at wound sites lessen their activities after epithelialization is completed. Termination of the wound healing process requires a fine balance between extracellular matrix (ECM) deposition and degradation. Maintaining this balance requires highly accurate epithelial‐mesenchymal communication and correct information exchange between keratinocytes and fibroblasts. As it has been reported in the literature, a disruption in epithelialization during the process of wound healing increases the frequency of developing chronic wounds or fibrotic conditions, as seen in a variety of clinical cases. Conversely, the potential stop signal for wound healing should have a regulatory role on both ECM synthesis and degradation to reach a successful wound healing outcome. This review briefly describes the potential roles of growth factors and cytokines in controlling the early phase of wound healing and predominantly explores the role of releasable factors from epithelial‐mesenchymal interaction in controlling during and the late stage of the healing process. Emphasis will be given on the crosstalk between keratinocytes and fibroblasts in ECM modulation and the healing outcome following a brief discussion of the wound healing initiation mechanism. In particular, we will review the termination of acute dermal wound healing, which frequently leads to the development of hypertrophic scarring.