bluuebunny/crossref_metadata_2025 huggingface dataset:
Carbapenem-resistant Klebsiella pneumoniae in university-affiliated hospitals: risk factors for isolation among hospitalized patients and molecular subtyping
Authors: Kobaidze Ketevan , Jacob Jesse , Leong Traci , Flanders W. Dana
Published: February 2022

Background

Carbapenem-resistant Klebsiella pneumoniae (CRKP) is an important healthcare-associated pathogen. This study aimed to identify factors associated with CRKP isolation among hospitalized patients, describe molecular epidemiology, and mortality associated with CRKP isolation.

Methods

We performed a retrospective case-control study at the two university-affiliated teaching hospitals. 150 patients were included (30 cases and 120 controls) in this study.

Each patient with CRKP, a case-patient, was matched with four controls by admission facility, age, and sex. Controls, patients without CRKP were randomly selected from a computerized list of inpatients whose admission date was the same as that of the case, within 48 hours of the date of the initial positive culture. We calculated the risk of in-hospital death as the number of deaths divided by the number of cases and evaluated the risk of mortality associated with the site of positive culture. Molecular epidemiology investigation using comparison of restricted DNA patterns of CRKP by pulsed-field gel electrophoresis (PFGE) was conducted.

Results

A greater proportion of cases than controls had undergone an invasive procedure, including use of a central vein catheter (p=0.007, OR, 3.4, 95% CI, 1.4-8.7), and mechanical ventilation (p=0.002, OR, 3.6, 95% CI, 1.6-8.1), nutrition by tube feeding (p=0.001, OR, 4.2, 95% CI, 1.8 −10).

Pre-admission treatment within two months with the following antibiotic classes was associated with CRKP isolation: carbapenems (p=0.001, OR, 24.4, 95% CI, 2.73-217.96), fluoroquinolones (p<0.0001, OR, 6.17, 95% CI, 2.4 – 15.83), anti-pseudomonal penicillin (p = 0.02; OR, 6.03; 95% CI, 1.98 −18.32), and cephalosporins (p=0.001, OR, 5.36, 95% CI, 2.07 −13.87).

The molecular analysis detected that over 90% of isolates shared similar PFGE patterns.

CRKP isolation was associated with significantly higher In-hospital mortality (36.7% vs 3.3%) in comparison to controls (p<.0001).

Positive cultures from sites other than urine were associated with substantially higher mortality than was a positive urine culture (RR= 4.0).
Model-based estimates of deaths averted and cost per life saved by scaling-up mRNA COVID-19 vaccination in low and lower-middle income countries in the COVID-19 Omicron variant era
Authors: Savinkina Alexandra , Bilinski Alyssa , Fitzpatrick Meagan C. , Paltiel A. David , Rizvi Zain , Salomon Joshua A. , Thornhill Tommy , Gonsalves Gregg
Published: February 2022

Background

While almost 60% of the world has received at least one dose of COVID-19 vaccine, the global distribution of vaccination has not been equitable. Only 4% of the population of low-income countries has received a full primary vaccine series, compared to over 70% of the population of high-income nations.

Methods

We used economic and epidemiologic models, parameterized with public data on global vaccination and COVID-19 deaths, to estimate the potential benefits of scaling up vaccination programs in low and lower-middle income countries (LIC/LMIC) in 2022 in the context of global spread of the Omicron variant of SARS-CoV2. Outcomes were expressed as number of avertable deaths through vaccination, costs of scale-up, and cost per death averted. We conducted sensitivity analyses over a wide range of parameter estimates to account for uncertainty around key inputs.

Findings

Global scale up of vaccination to provide two doses of mRNA vaccine to everyone in LIC/LMIC would cost $35.5 billion and avert 1.3 million deaths from COVID-19, at a cost of $26,900 per death averted. Scaling up vaccination to provide three doses of mRNA vaccine to everyone in LIC/LMIC would cost $61.2 billion and avert 1.5 million deaths from COVID-19 at a cost of $40,800 per death averted. Lower estimated infection fatality ratios, higher cost-per-dose, and lower vaccine effectiveness or uptake lead to higher cost-per-death averted estimates in the analysis.

Interpretation

Scaling up COVID-19 global vaccination would avert millions of COVID-19 deaths and represents a reasonable investment in the context of the value of a statistical life (VSL). Given the magnitude of expected mortality facing LIC/LMIC without vaccination, this effort should be an urgent priority.
Signatures of immune senescence predict outcomes and define checkpoint blockade-unresponsive microenvironments in acute myeloid leukemia
Authors: Rutella Sergio , Vadakekolathu Jayakumar , Mazziotta Francesco , Reeder Stephen , Yau Tung-On , Mukhopadhyay Rupkatha , Dickins Benjamin , Altmann Heidi , Kramer Michael , Knaus Hanna , Blazar Bruce R. , Radojcic Vedran , Zeidner Joshua F. , Arruda Andrea , Minden Mark D. , Tasian Sarah K. , Bornhäuser Martin , Gojo Ivana , Luznik Leo
Published: February 2022

The function of senescent-like T cells, transcriptomic features of immune effector senescence (IES) and their influence on therapeutic response were investigated in independent AML clinical cohorts comprising 1,864 patients treated with chemotherapy and/or immune checkpoint blockade (ICB). We show that senescent-like bone marrow CD8+T cells are impaired in killing autologous AML blasts, and that their proportion negatively correlates with overall survival (OS). We define new IES signatures using two gene expression platforms and report that IES scores correlate with adverse-risk molecular lesions, stemness, and poor outcomes as a potentially more powerful predictor of OS than 2017-ELN risk or LSC17 stemness score. IES expression signatures also identify an ICB- unresponsive tumor microenvironment and predict significantly worse OS in AML as well as in solid tumors. The newly described IES scores provide improved AML risk stratification and could facilitate the delivery of personalized immunotherapies to patients who are most likely to benefit.
Safety and immunogenicity of inactivated whole virion vaccine CoviVac against COVID-19: a multicenter, randomized, double-blind, placebo-controlled phase I/II clinical trial
Authors: Ishmukhametov Aydar A , Siniugina Aleksandra A , Yagovkina Nadezhda V , Kuzubov Vladimir I , Zakharov Konstantin A , Volok Viktor P , Dodina Maria S , Gmyl Larissa V , Korotina Natalya A , Theodorovich Rostislav D , Ulitina Yulia I , Tsaan Andrey A , Pomaskina Tatiana V , Kalenskaya Anna V , Solovjeva Irina V , Tivanova Elena V , Kondrasheva Larissa Y , Ploskireva Antonina A , Akimkin Vasiliy G , Subbotina Ksenia A , Ignatyev Georgy M , Korduban Anastasia K , Shustova Elena Y , Bayurova Ekaterina O , Kondrashova Alla S , Avdoshina Darya V , Piniaeva Anastasia N , Kovpak Anastasia A , Antonova Liliya P , Rogova Yulia V , Shishova Anna A , Ivin Yury Y , Sotskova Svetlana E , Chernov Konstantin A , Ipatova Elena G , Korduban Ekaterina A , Kozlovskaya Liubov I , Gordeychuk Ilya V
Published: February 2022

We present the results of a randomized, double-blind, placebo-controlled, multi-center clinical trial of the tolerability, safety, and immunogenicity of the inactivated whole virion concentrated purified coronavirus vaccine CoviVac in adult volunteers aged 18-60.

Safety of the vaccine was assessed in 398 volunteers who received two doses of the vaccine (n=298) or placebo (n=100). The studied vaccine has shown good tolerability and safety. No deaths, serious adverse events (AE), or other significant AE related to vaccination have been detected. The most common AE in vaccinated participants was pain at the injection site (p<0.05).

Immunogenicity assessment was performed in 167 volunteers (122 vaccinated and 45 in Placebo Group) separately for the participants who were anti-SARS-CoV-2 nAB negative (69/122 in Vaccine Group and 28/45 in Placebo Group) or positive (53/122 in Vaccine Group and 17/45 in Placebo Group) at screening.

At Day 42 after the first immunization the seroconversion rate in participants who were seronegative at screening was 86.9% with average the geometric mean neutralizing antibody (nAB) titer of 1:20. Statistically significant (p<0.05) increase of IFN-γ production by peptide-stimulated T-cells was observed at Days 14 and 21 after the first immunization.

In participants who were seropositive at screening but had nAB titers below 1:256 the rate of 4-fold increase in nAB levels was 85.2%, while in the participants with nAB titers >1:256 the rate of 4-fold increase in nAB levels was below 45%. For the participants who were seropositive at screening the second immunization did not lead to a significant increase in nAB titers.

In conclusion, inactivated vaccine CoviVac has shown good tolerability and safety, with 86.9% seroconversion rates in participants, who were seronegative at screening. In participants who were seropositive at screening and had nAB titers below 1:256, a single immunization lead to a 4-fold increase in nAB levels in 85.2% cases.
Genome-wide Analysis of Bromodomain Gene Family in Arabidopsis and Rice
Authors: Abiraami T.V. , Sanyal Ravi Prakash , Misra Hari Sharan , Saini Ajay
Published: February 2022

The bromodomain containing proteins (Brd-proteins) belongs to family of ‘epigenetic mark readers’, integral to epigenetic regulation. The Brd-members contain a conserved ‘bromodomain’ (BRD/BRD-fold: interacts with acetylated-lysine in histones), and several additional domains, making them structurally/functionally diverse. Like animals, plants also contain multiple Brd-homologs, however the extent of their diversity and impact of molecular events (genomic duplications, alternative splicing, AS) therein, is relatively less explored. The present genome-wide analysis of Brd-families of Arabidopsis thaliana and Oryza sativa showed extensive diversity in structure of genes/proteins, regulatory elements, expression pattern, domains/motifs, and the bromodomain (length/sequence, location) among Brd-members. Orthology analysis identified 13 ortholog groups, three paralog groups and four singleton members. While more than 40% Brd-genes were affected by genomic duplication events in both plants, AS-events affected 60% A. thaliana and 40% O. sativa genes. These molecular events affected various regions (promoters, untranslated regions, exons) of different Brd-members with potential impact on expression/structure-function characteristics. RNA-Seq data analysis of Brd-members, and RT-qPCR of duplicate Brd-genes showed differences in tissue-specificity and response to salinity. Phylogenetic analysis based on conserved BRD-region placed the A. thaliana and O. sativa homologs into clusters/sub-clusters, consistent with ortholog/paralog groups. The bromodomain-region displayed conserved signatures in key BRD-fold elements (α-helices, loops), and variations (1-20 sites) including indels among the Brd-duplicates. Homology modeling and superposition identified structural variations in BRD-folds of divergent and duplicate Brd-members, which might affect their interaction with chromatin and associated functions. The study also showed contribution of various duplication events in Brd-family expansion among diverse plants, including monocots and dicots.
A bacterial pan-genome makes gene essentiality strain-dependent and evolvable
Authors: Rosconi Federico , Rudmann Emily , Li Jien , Surujon Defne , Anthony Jon , Frank Matthew , Jones Dakota S. , Rock Charles , Rosch Jason W. , Johnston Christopher D. , van Opijnen Tim
Published: February 2022

Many bacterial species are represented by a pan-genome, whose genetic repertoire far outstrips that of any single bacterial genome. Here we investigate how a bacterial pan-genome might influence gene essentiality, and whether essential genes that are initially critical for the survival of an organism can evolve to become non-essential. By using Tn-Seq, whole-genome sequencing, and RNA-Seq on a set of 36 clinicalStreptococcus pneumoniaestrains representative of >68% of the species’ pan-genome, we identify a species-wide ‘essentialome’ that can be subdivided into universal, strain-specific and accessory essential genes. By employing ‘forced-evolution experiments’ we show that specific genetic changes allow bacteria to bypass essentiality. Moreover, by untangling several genetic mechanisms we show that gene-essentiality can be highly influenced and/or dependent on: 1) the composition of the accessory genome; 2) the accumulation of toxic intermediates; 3) functional redundancy; 4) efficient recycling of critical metabolites; and 5) pathway rewiring. While this functional characterization underscores the evolvability-potential of many essential genes, we also show that genes with differential essentiality remain important antimicrobial drug target candidates, as their inactivation almost always has a severe fitness costin vivo.
Functionally competent CD4+ T cells express high levels of T-bet in Plasmodium chabaudi infected young mice
Authors: Smith Margaret R. , Gbedande Komi , Johnson Corey M. , Campbell Logan A. , Richard Lyndsay B. , Onjiko Robert S. , Domingos Nadia , Opata Michael M.
Published: February 2022

The immune system plays an important role in the elimination of Plasmodium parasites that cause malaria, which affect children the most worldwide. Immunity to malaria, especially in young children is poorly understood due to the absence of a developmentally-equivalent rodent model to study the pathogenesis of disease. We have developed a mouse model using 15-day old mice (pups) of malaria infection in neonatal mice. Using C57BL/6 pups, we determined that P. chabaudi infection decreases the growth rate of young mice compared to controls, and results in 60% mortality, and neurological damage not present in adults, as indicated by a battery of behavioral assays. When all splenic cells were stimulated in vitro stimulation, cells from pups proliferated faster than adult cells, but purified CD4 T cells were slower. Upon infection with Plasmodium parasites, both adult and pup CD4+ T cells were activated and differentiated to an effector T cell (Teff) phenotype; however, pup CD4+ Teff were less differentiated than adult Teff. Pup CD4+ T cells also produced more IL-2 than cells from adult B6 mice, and TNF-α was increased in parasite-specific BALB/c pup T cells. Interestingly, there were more pup CD4+T-bethi Teff after infection suggestive of increased Th1 commitment, potentially contributing to cerebral symptoms.
Worldwide antibiotic resistance dynamics: how different is it from one drug-bug pair to another?
Authors: Rahbe Eve , Watier Laurence , Guillemot Didier , Glaser Philippe , Opatowski Lulla
Published: February 2022

Background

Antibiotic resistance (ABR) is a major concern for global health. However, factors driving its emergence and dissemination are not fully understood. Identification of such factors is crucial to explain heterogeneity in ABR rates observed across space, time and species and antibiotics.

Methods

We analyzed count data of clinical isolates from 51 countries over 2006-2019 for thirteen drug-bug pairs from the ATLAS surveillance system. We characterized ABR spatial and temporal patterns and used a mixed-effect negative binomial model, accounting for country-year dependences with random effects (RE), to investigate associations with potential drivers including antibiotic sales, economic and health indicators, meteorological data, population density and tourism.

Findings

ABR patterns were strongly country and drug-bug pair dependent. In 2019, median ABR rates ranged from 6×3% (interquartile range (IQR): 19×7%) for carbapenem-resistant (CR)Klebsiella pneumoniaeto 80×7% (IQR: 41×8%) for fluoroquinolone-resistant (FR)Acinetobacter baumannii, with heterogeneity across countries. Over 2006-2019, carbapenem resistance was on the rise in >60% of investigated countries, while no global trend was observed for other resistances. Multivariable analyses identified significant associations of ABR with country-level selecting antibiotic sales, but only in FR-Escherichia coli, FR-Pseudomonas aeruginosaand CR-A. baumannii;with temperature in investigated Enterobacterales but not in other drug-bug pairs; and with the health system quality for all drug-bug pairs exceptEnterococciandStreptococcus pneumoniaepairs. Despite wide consideration of possible explanatory variables, drug-bug pairs ABR rates still showed unexplained spatial RE variance.

Interpretation

Our findings reflect the diversity of mechanisms driving global antibiotic resistance across pathogens and stress the need for tailored interventions to tackle bacterial resistance.

Funding

Independent research Pfizer Global Medical Grant; ANR Labex IBEID (ANR-10-LABX-62)
Characterization of the gene expression profile in younger and older low-grade glioma patients
Authors: Dong Cathryn , Fei Xiang , Guo Youtang , Jiang Minde , Mao Yifan , Wang Zhaoying , Wei Yutong , Yu Tianyi , Shi Yong , Yang Yi , Qing Tao , Zhu Sibo
Published: February 2022

Low-grade gliomas (LGG) are the slowest growing type of brain cancer that often affects young adults. Of all LGG cases, older patients were associated with the poor prognosis compared to younger patients. However, the molecular mechanism underlying this association remains unclear. Here, we compared genes expression profiles between younger (age≤50) and older (age > 50) patients from The Cancer Genome Atlas (TCGA) and demonstrate the age-related gene expressions. Pathway and gene set enrichment analysis reveal that differentially expressed genes (DEGs) between tumors of older and younger patients have been involved in cancer-related biological procedures, such as, transcriptional misregulation in cancer, nucleotide synthesis, mTOR, and DNA damage repair signaling. We also demonstrated that older patients have higher expression of Mitosis Kinase Score (MKS) and Tumor Inflammation Signature (TIS) which reflects high cell proliferation and high immune cell activity; respectively. The comprehensive characterization of gene-expression profiles in younger versus older LGG may explain the age-related prognosis and facilitate the development of potential therapeutic biomarkers for LGG.
A regulatory network of Sox and Six transcription factors initiate a cell fate transformation during hearing regeneration in adult zebrafish
Authors: Jimenez Erin , Slevin Claire C. , Song Wei , Chen Zelin , Frederickson Stephen C. , Gildea Derek , Wu Weiwei , Elkahloun Abdel G. , Ovcharenko Ivan , Burgess Shawn M.
Published: February 2022

Using adult zebrafish inner ears as a model for sensorineural regeneration, we performed a targeted ablation of the mechanosensory receptors in the utricle and saccule and characterized the single-cell epigenome and transcriptome at consecutive time-points following hair cell ablation. Using deep learning on the regeneration-induced open chromatin sequences, we were able to identify unique, cell-specific transcription factor (TF) motif patterns enriched in the raw data. We correlated enhancer activity with gene expression to identify gene regulatory networks. A clear pattern of overlapping Sox- and Six-family transcription factor gene expression and binding motifs was detected, suggesting a combinatorial program of TFs driving regeneration and cell identity. Pseudo-time analysis of single-cell transcriptomic data demonstrated that the support cells within the sensory epithelium changed cell identity to a more pluripotent “progenitor” cell population that could either differentiate into hair cells or return to a support cell identity. We showed thatsox2becomes enriched in the progenitor cells and is reduced again when the cells differentiate in either direction. Analysis of the scATAC-seq data identified a 2.6 kb DNA sequence element upstream of thesox2promoter that dynamically changed in accessibility during hair cell regeneration. When deleted, the upstream regulator ofsox2showed a dominant phenotype that resulted in a hair cell regeneration-specific deficit in both the lateral line and adult inner ear.

HIGHLIGHTS

Integrated scRNA-seq and scATAC-seq of the adult zebrafish inner ear during hair cell regeneration.

Support cells transition to an intermediate cell type that can differentiate to hair cells. Coordinated expression of Sox and Six transcription factors are key to hearing regeneration.

Sox transcription factors trigger the regeneration response in the support cells while Sox and Six factors cooperate during hair cell differentiation.

Deletion of an upstream enhancer that controls the timing ofsox2expression causes regeneration-specific defects in hearing regeneration.
Adipose cells and tissues soften with lipid accumulation while in diabetes adipose tissue stiffens
Authors: Abuhattum Shada , Kotzbeck Petra , Schlüßler Raimund , Harger Alexandra , Schellenberger Angela Ariza , Kim Kyoohyun , Escolano Joan-Carles , Müller Torsten , Braun Jürgen , Wabitsch Martin , Tschöp Matthias , Sack Ingolf , Brankatschk Marko , Guck Jochen , Stemmer Kerstin , Taubenberger Anna V.
Published: February 2022

Adipose tissue expansion involves both differentiation of new precursors and size increase of mature adipocytes. While the two processes are well balanced in healthy tissues, obesity and diabetes type II are associated with abnormally enlarged adipocytes and excess lipid accumulation. We hypothesised that adipocyte shape and size changes with differentiation and lipid accumulation would be accompanied by changes in the mechanical phenotype at both the cell and tissue level. We quantified by optical diffraction tomography (ODT) that differentiating preadipocytes increased their volumes drastically. Atomic force microscopy (AFM)-indentation and -microrheology revealed that during the early phase of differentiation, human preadipocytes became more compliant and more fluid-like, concomitant with ROCK-mediated F-actin remodelling. Adipocytes that had accumulated large lipid droplets were more compliant, and further promoting lipid accumulation led to an even more compliant phenotype. In line with that, high fat diet-induced obesity was associated with more compliant adipose tissue compared to lean animals, both for drosophila fat bodies and murine gonadal adipose tissue. In contrast, adipose tissue of diabetic mice became significantly stiffer as shown not only by AFM but also magnetic resonance elastography (MRE). Altogether, we dissect relative contributions of the cytoskeleton and lipid droplets to cell and tissue mechanical changes across different functional states, such as differentiation, nutritional state and disease. Since preadipocytes are mechanosensitive, tissue stiffening in diabetes might be critical to the balance between hyperplasia and hypertrophy and moreover present a potential target in the prevention of metabolic disorders.
Anti-inflammatory effects of WFS1 in pancreatic β-cells
Authors: Morikawa Shuntaro , Blacher Lindsey , Onwumere Chinyere , Urano Fumihiko
Published: February 2022

Wolfram syndrome is a rare genetic disorder characterized by juvenile-onset diabetes mellitus, optic nerve atrophy, hearing loss, diabetes insipidus, and progressive neurodegeneration. Pathogenic variants in the WFS1 gene are the main causes of Wolfram syndrome. WFS1 encodes a transmembrane protein localized to the endoplasmic reticulum (ER) and regulates the unfolded protein response (UPR). Loss of function of WFS1 leads to dysregulation of insulin production and secretion, ER calcium depletion, and cytosolic calpains activation, resulting in activation of apoptotic cascades. Although the terminal UPR has been shown to induce inflammation that accelerates β-cell dysfunction and death in diabetes, the contribution of β-cell inflammation to the development of diabetes in Wolfram syndrome has not been fully understood. Here we show that WFS1-deficiency enhances the gene expression of inflammatory cytokines and chemokines, leading to cytokine-induced ER-stress and cell death in pancreatic β-cells. PERK and IRE1α pathways mediate high glucose-induced inflammation in a β-cell model of Wolfram syndrome. M1-macrophage infiltration and hypervascularization are seen in the pancreatic islets of Wfs1 whole-body knockout mice, demonstrating that WFS1 regulates anti-inflammatory responses in β-cells. Our results demonstrate that inflammation plays an essential role in the progression of β-cell death and diabetes in Wolfram syndrome and reveal that the pathways involved in ER stress-mediated inflammation provide potential therapeutic targets for the treatment of Wolfram syndrome.
The Role of Notch Signaling in Endometrial Mesenchymal Stromal/Stem-like Cells Maintenance
Authors: Zhang Sisi , Chan Rachel W.S. , Ng Ernest H.Y. , Yeung William S.B.
Published: February 2022

Human endometrium undergoes cycles of regeneration in reproductive women. The endometrial mesenchymal stromal/stem cells (eMSC) contribute to this process. Notch signaling is essential for the homeostasis of somatic stem cells. However, its role in eMSC remains unclear. The gain and loss function shows that activation of Notch signaling promotes eMSC maintenance, while inhibition displays opposite effect. Activation of Notch pathway better maintains eMSC in a quiescent state. However, these quiescent eMSC can re-enter into the cell cycle depending on Notch and Wnt activity in the microenvironment, suggesting a crosstalk between two signaling pathways. In a mouse menstrual-like model, we observe that Notch signaling is highly involved in the dynamic endometrial remodeling event. Suppression of Notch signaling significantly reduces the proliferation of Notch1+ label-retaining stromal cells and consequently delays the endometrial repair. Our data demonstrate the importance of Notch signaling in regulating the endometrial stem/progenitor cells in vitro and in vivo.
The Composition of Diesel Fuel Influences the Structure of Microbiological Assemblages in Contaminated Storage Tanks
Authors: Floyd James G. , Stamps Blake W. , Bojanowski Caitlin L. , Goodson Wendy J. , Stevenson Bradley S.
Published: February 2022

Microbiological contamination in diesel storage tanks is widespread and under-reported. The contaminating microorganisms can degrade components of the fuel, which contributes to fouling and corrosion. To better understand the connection between the microorganisms that are responsible for this contamination, the composition of affected fuels, and the resulting impact on fuel quality, we conducted a survey of 106 fuel tanks at 17 military bases across the continental United States. Fuel was sampled from each tank and the resident microbial communities were characterized using high throughput sequencing of small subunit ribosomal RNA gene libraries. Fatty acid methyl esters (FAME) and n-alkanes were characterized and quantified using GC-MS to determine their correlation with the presence of microbial taxa. Redundancy Analyses identified which microbial taxa were more prominent in contaminated fuels. Members of the fungal family Trichomaceae were found to be prominent in fuels containing more FAME. Members of the yeast family Debaryomycetaceae were found to be prominent in fuels containing more pentadecanoic and oleic acid methyl esters. These relationships between fungal taxa and fuel components were directly tested in growth experiments with representative isolates of the Trichocomaceae (Paecilomyces AF001) and Debaryomycetaceae (Wickerhamomyces SE3) families. Paecilomyces was capable of growth on linoleic acid methyl ester but unable to grow on pentadecanoic acid methyl ester, while Wickerhamomyces was able to grow on both substrates. Fuel composition may provide some insight into which microorganisms can proliferate but other factors like competition and symbiosis may also drive microbial proliferation, fouling, degradation, and corrosion in diesel fuels.

Importance

Biodiesel, widely used as an additive or extender of ultra-low sulfur diesel, can increase the potential for microorganisms to proliferate in storage tanks. It is important to know how the composition of diesel fuels can influence the growth of organisms linked to fuel degradation and microbiologically influenced corrosion. This research describes how certain populations of fungi and bacteria can prevail in fuels of different composition, which can be helpful in predicting biodegradation and biocorrosion, and formulating fuels less susceptible to the growth of problematic organisms.
Examination of rickettsial host range for shuttle vectors based on dnaA and parA genes from the pRM plasmid of Rickettsia monacensis
Authors: Burkhardt Nicole Y. , Price Lisa D. , Wang Xin-Ru , Heu Chan C. , Baldridge Gerald D. , Munderloh Ulrike G. , Kurtti Timothy J.
Published: February 2022

The genus Rickettsia encompasses a diverse group of obligate intracellular bacteria that are highly virulent disease agents of mankind as well as symbionts of arthropods. Native plasmids of Rickettsia amblyommatis (AaR/SC) have been used as models to construct shuttle vectors for genetic manipulation of several Rickettsia species. Here we report on the isolation of the complete plasmid (pRM658B) from Rickettsia monacensis (IrR/Munich) mutant Rmona658B and the construction of shuttle vectors based on pRM. To identify regions essential for replication, we made vectors containing the dnaA and parA genes of pRM with varying portions of the region surrounding these genes and a selection-reporter cassette conferring resistance to spectinomycin and expression of green fluorescent protein. Rickettsia amblyommatis (AaR/SC), R. monacensis (IrR/Munich), Rickettsia bellii (RML 369-C), Rickettsia parkeri (Tate’s Hell), and Rickettsia montanensis (M5/6) were successfully transformed with shuttle vectors containing pRM parA and dnaA. PCR assays targeting pRM regions not included in the vectors revealed that native pRM was retained in R. monacensis transformants. Determination of native pRM copy number using a plasmid-encoded gene (RM_p5) in comparison to chromosomal encoded gltA indicated reduced copy numbers in R. monacensis transformants. In transformed R. monacensis, native pRM and shuttle vectors with homologous parA and dnaA formed native plasmid-shuttle vector complexes. These studies provide insight on the maintenance of plasmids and shuttle vectors in rickettsiae.

IMPORTANCE

This paper describes a new series of plasmid shuttle vectors for the transformation of rickettsiae.

Shuttle vectors based on parA and dnaA sequences of the plasmid pRM can be used to transform diverse rickettsia as well as its native host Rickettsia monacensis.

Our results provide insight into the maintenance of rickettsial-based shuttle vectors in rickettsiae.
QUANTAS: a Python software for the analysis of thermodynamics and elastic behavior of solids fromab initioquantum mechanical simulations and experimental data
Authors: Ulian Gianfranco , Valdrè Giovanni
Published: February 2022

Mineralogy, petrology and materials science are fundamental disciplines not only for the basic knowledge and classification of solid phases but also for their technological applications, which are becoming increasingly demanding and challenging. Characterization and design of materials are of utmost importance and usually need knowledge of the thermodynamics and mechanical stability of solids. Alongside well known experimental approaches, in recent years the advances in both quantum mechanical methods and computational power have placed theoretical investigations as a complementary useful and powerful tool in this kind of study. In order to aid both theoreticians and experimentalists, an open-source Python-based software,QUANTAS, has been developed.QUANTASprovides a fast, flexible, easy-to-use and extensible platform for calculating the thermodynamics and elastic behavior of crystalline solid phases, starting from both experimental andab initiodata.
Are sake brewers and marketers sending the wrong message to consumers?
Authors: Smith Ryan P. , Ma Forest , McKercher Bob , Baldwin Watson Maceo
Published: February 2022

Purpose

This study investigates Hong Kong “consumers” sake tasting preferences, willingness to pay and how information commonly found on the bottle or menu affects these attributes.

Design/methodology/approach

This study took place inside a four-star hotel lobby restaurant. Convenience sampling was used to collect 184 valid responses from Hong Kong residents. Respondents were given four sakes two blind and two with common information found on the bottles and asked to rate each one independently.

Findings

The results suggest that alcohol content is the most crucial attribute in assessing the overall liking for consumers. In addition, information currently provided by producers and brewers has a negative effect on all assessment attributes and overall liking, but a positive effect on willingness to pay.

Practical implications

Sake producers, brewers, marketers, and hotel food and beverage managers should reconsider marketing strategies and the type of information provided to send better signals, increase “consumers” assessment and their overall liking. The results of this study suggest that sake brewers may want to advertise the alcohol content better to achieve higher satisfaction.

Originality/value

Consumers taste preferences for sake are not well understood. By applying the signalling theory the study results filled an information gap by examining how sake information commonly found on labels affects hotel guests tasting preferences and willingness to pay.
Does board composition influence working capital management? Evidence from Thailand
Authors: Kumpamool Chamaiporn , Chancharat Nongnit
Published: February 2022

Purpose

This study aims to investigate the influence of board composition on the working capital management (WCM) of Thai listed firms for the period 2010–2019.

Design/methodology/approach

Probit regression and two-step system generalized method of moments (GMM) are used to address this issue.

Findings

The results indicate that, while a larger board size causes a lower net working capital holding, it increases its efficiency. Firms with chief executive officer (CEO) duality adopt aggressive policies for their financing but avoid them for their investment to balance the risks and returns of implementing the working capital (WC) policy. Conversely, firms with higher board independence prefer to use conservative WC financing policies. The findings support using both the agency and stewardship theories.

Research limitations/implications

The authors focus on listed non-financial firms; therefore, the findings may not be generalizable to financial and private firms.

Practical implications

The findings provide implications for practitioners to focus more on board composition, as it is crucial for WCM. Furthermore, they should avoid applying a single theory in isolation, especially for CEO duality, as one theory is appropriate only for some policies. The authors also provide guidelines for policymakers and regulators to formulate strategies that support more board diversification in terms of size and independence, to enhance board efficiency.

Originality/value

To the best of the author’s knowledge, this study is the first to directly examine the influence of board composition on aggressive WC policies in Thailand.
Role of socioemotional wealth (SEW) in the internationalisation of family firms
Authors: Jain Apoorva , Thukral Sonal , Paul Justin
Published: February 2022

Purpose

Family firms' desire to preserve and uphold socioemotional wealth (SEW) makes their internationalisation a complex phenomenon. Despite the significance of SEW in guiding family firms' internationalisation decisions, the literature in the underlying research stream is still scant and inconclusive. Thus, the purpose of the study is to gain preliminary insights about various dimensions of SEW and its impact on family firms' degree of internationalisation.

Design/methodology/approach

The study employs the multi-case study research design. The multidimensional SEW scale developed by Berrone et al. (2012) is used to calculate the SEW scores for four prominent Indian family businesses through the content analysis of Chairman's Statements for a period of 13 years (2007–08 to 2019–20). Further, the study examines the relationship between SEW and family firms' degree of internationalisation through two non-parametric tests: Somers' D and Kendall-Theil regression.

Findings

The results reveal the prevalence of various dimensions of SEW in family businesses. They also indicate that different FIBER dimensions are prioritised differently in family businesses. Finally, the authors observe that there exists a negative relationship between SEW and internationalisation of family businesses, indicating that SEW hinders the internationalisation of family firms.

Research limitations/implications

The study lends to the readers, the understanding that SEW plays a significant role in the internationalisation of family firms; thus, some modification might be needed in the existing international business theories in order to explain the role of peculiar family characteristics in the internationalisation decisions of family firms. Further, since SEW hinders the internationalisation of family firms, it raises a question for researchers and family business leaders: Do family firms need to work on their socioemotional ties to avoid making suboptimal decisions?

Originality/value

The study is a response to the call by Cleary et al. (2019) to utilise the results of content analysis of SEW in determining its impact on the family firms' external events. Majority of the studies are still using univariate measures (e.g. percentage of family ownership) to capture SEW. However, this study attempts to calculate the SEW scores of the family firms along these FIBER dimensions through content analysis. This helps in scrupulously capturing the impact of SEW in the internationalisation of family firms.
Servant leadership and organisational citizenship behaviour: the role of public service motivation and length of time spent with the leader
Authors: Gnankob Robert Ipiin , Ansong Abraham , Issau Kassimu
Published: February 2022

Purpose

The study examined the influence of servant leadership on organisational citizenship behaviour (OCB) of employees in Ghana through the intervening roles of public service motivation (PSM) and the length of time spent with the leader.

Design/methodology/approach

A structured questionnaire was used to gather data from 328 randomly sampled respondents within the six metropoles in Ghana for data analysis. The partial least squares structural equation modelling (PLS-SEM) was used to address the hypotheses of the study.

Findings

The study found that servant leadership has a significant positive influence on OCB and PSM. The study also found that PSM significantly and positively influences OCB. The study finally established that whiles PSM significantly mediated the relationship between servant leadership and OCB, the length of time spent with leaders did not moderate the servant leadership and OCB nexus.

Practical implications

The study implies that stakeholders in the local government sector, such as the Local Government Service Board, should emphasise employing or promoting supervisors who are servant leadership-driven to occupy key positions within the local government structure. Efforts could also be made to train the supervisors to acquire servant leadership traits.

Originality/value

The results from the study provide significant insights on how the public sector in Ghana and beyond can identify, develop and maintain servant leaders to promote employees OCB. Also, being a pioneering study in Ghana, the results and recommendations from the study have set the pace for future scholars to discuss issues that engulf the public sector.
Perceptions of politics and organizational citizenship behavior: political skill and conscientiousness as moderators
Authors: Tripathi Divya , Singh Shailendra , Varma Arup
Published: February 2022

Purpose

The purpose of this paper is to examine how perceptions of politics (POP) impact individuals’ willingness to engage in organizational citizenship behavior (OCB) and how this relationship is impacted by individuals’ conscientiousness and political skills.

Design/methodology/approach

Primary data collected from 211 employee working in the consultancy sector in India were analyzed using hierarchical moderated regression technique.

Findings

The authors found a significant three-way interaction between POP, conscientiousness and political skill in predicting OCB. Presence of high conscientiousness and high political skill alleviates the negative effect of politics on OCB.

Research limitations/implications

The data were collected from consultancy sector organizations, and thus, generalizability of the results is somewhat limited. Further, self-report surveys are used for data collection. Future studies should use multiple methods to collect data to avoid common method bias.

Practical implications

The results suggest that to alleviate the negative effect of POP on OCB, practitioners should recruit employees with high levels of conscientiousness and impart training to develop political skill.

Originality/value

This study attempts to take a holistic person-centric approach to study the moderating effect of personality variable and political skill when examining the linkage between perceived politics and citizenship behavior.
Economic efficiency of higher education institutions in Vietnam between 2012 and 2016: a DEA analysis
Authors: Tran Thien-Vu , Pham Thao Phuong , Nguyen Mai-Huong , Do Long-Thanh , Pham Hiep-Hung
Published: February 2022

Purpose

This paper aims to examine the economic efficiency of Vietnamese 172 higher education (HE) institutions within the 2012–2016 inclusive period through the Data Envelopment Analysis (DEA) approach. The authors also compare public and private, multidisciplinary and mono-disciplinary, non-autonomy and autonomy, non-international and international HE Institutions’ efficiency.

Design/methodology/approach

This study derived from an unique dataset from the Ministry of Education and Training (MOET) of Vietnam. The data set comprises financial and academic annual reports of higher education institutions (HEIs). The authors achieved totally 204 Vietnamese HEIs, and the sample for analysis is 172 after the elimination of missing units, accounting for 84.3% entire of Vietnamese HEIs. The authors estimate the efficiency scores relying on these selected inputs and outputs by using the DEA method.

Findings

Overall, HEIs in Vietnam decreased their operational efficiency during the 2012–2016. It also seems that public universities operate in the absence of market mechanism so that they tend to be less efficient than their counterparts in private sector. Based on our analysis, the authors observe that the HEIs including the international programmes have higher efficiency scores rather than these without international programmes.

Originality/value

This study contributes to the theoretical aspects as follows. First, it enriches the existent efficiency literature on HE using the DEA approach. This stands out among similar studies in Vietnam in terms of duration (from 2012–2016) and data size (172 entities). Second, the research is the first to examine HEIs in terms of disciplinary (mono or multi-disciplinary) and autonomy (autonomous and non-autonomous), internalization (international programmes). These aspects have been silent in previous studies of HEIs in Vietnam.
Environmental degradation effect on agricultural development: an aggregate and a sectoral evidence of carbon dioxide emissions from Ghana
Authors: Kwakwa Paul Adjei , Alhassan Hamdiyah , Adzawla William
Published: February 2022

Purpose

Quality environment is argued to be essential for ensuring food security. The effect of environmental degradation on agriculture has thus gained the attention of researchers. However, the analyses of aggregate and sectoral effect of carbon dioxide emissions on agricultural development are limited in the literature. Consequently, this study examines the effect of aggregate and sectoral carbon emissions on Ghana's agricultural development.

Design/methodology/approach

Time-series data from 1971 to 2017 are employed for the study. Regression analysis and a variance decomposition analysis are employed in the study.

Findings

The results show that the country's agricultural development is negatively affected by aggregate carbon emission while financial development, labour and capital increases agricultural development. Further, industrial development and emissions from transport sector, industrial sector and other sectors adversely affect Ghana's agriculture development. The contribution of carbon emission together with other explanatory variables to the changes in agricultural development generally increases over the period.

Originality/value

This study analyses the aggregate and sectoral carbon dioxide emission effect on Ghana's agricultural development.
Fear of missing out (FOMO) to the joy of missing out (JOMO): shifting dunes of problematic usage of the internet among social media users
Authors: Rautela Sonica , Sharma Sarika
Published: February 2022

Purpose

With the rapid improvement in digital infrastructure, the popularity of digital devices and smartphones in every pocket, the yearning to stay connected with others has increased manifold, especially in youngsters. This has raised multiple concerns primarily related to the problematic usage of the internet (PUI). The current research study aims to scrutinize the association between PUI, psychological and mental health (PMH), social media fatigue (SMF), fear of missing out (FOMO), desire to disconnect (DD) and its relation with a novel phenomenon of joy of missing out (JOMO).

Design/methodology/approach

The present research study embraces the empirical research method through quantitative analysis. The proposed theoretical model was empirically tested using primary data, collected through a self-designed structured questionnaire. The study sample included individuals between 16 and 39 years of age as these are the most active demographics on social media. The model is empirically tested with the help of structural equation modeling applied using software IBM AMOS 20.0 and SPSS 22.0. Initially, first-order confirmatory factor analysis was conducted, to measure and test the fit indices of the proposed model. Secondly, path analysis using structural equation modeling was carried out for the model.

Findings

Empirical synthesis of this research shows that PUI significantly and positively impacts mental and psychological health, FOMO and SMF. Also, SMF significantly and positively affects the DD which significantly and positively affects the JOMO. However, as depicted by the results of this study, FOMO have no considerable impact on SMF.

Originality/value

A study that connects the PUI with PMH, SMF and FOMO is rare to find. Second, this study uses data collected from social media users of India in the age group of 16–39 years. This slice of the population is most active in internet, and internet-enabled platform and are scantly studied, especially in the Indian context. This makes the study more exciting and crucial.