bluuebunny/crossref_metadata_2025_split huggingface dataset:
Energy dependence of signalling dynamics and robustness in bacterial two component systems
Authors: Forrest Joshua , Pan Michael , Crampin Edmund J. , Rajagopal Vijay , Stumpf Michael PH 
Published: February 2023

AbstractOne of the best known ways bacteria cells understand and respond to the environment are through Two-Component Systems (TCS). These signalling systems are highly diverse in function and can detect a range of physical stimuli including molecular concentrations and temperature, with a range of responses including chemotaxis and anaerobic energy production.TCS exhibit a range of different molecular structures and energy costs, and multiple types co-exist in the same cell. TCSs that incur relatively high energy cost are abundant in biology, despite strong evolutionary pressure to efficiently spend energy.We are motivated to discern what benefits, if any, the more energetically expensive variants had for a cell.We seek to answer this question by modelling energy flow through two variants of TCS. This was accomplished using bond graphs, a physics-based modelling framework that accurately models energy transfer through different physical domains. Our analysis demonstrates that energy availability can affect a cell’s signal sensitivity, noise filtering effectiveness, and the stimulus level where cell response is maximal. We also found that these properties are determined not by the molecular parameters themselves, but the reaction rate parameters that govern the reaction systems as a whole.This suggests possible connections between the molecular structure and evolutionary purpose of any two-component system. This opens the door to new synthetic circuit design in systems biology, and we propose new hypotheses about this link between structure and purpose that could be experimentally verified.Author summaryTwo-component systems are the main way many bacteria sense and respond to their environment. They exist in such well-studied bacteria asE. coliwhere they have been shown to detect a range of stimuli including nutrients, temperature, acidity, and pressure.Two-component systems are ubiquitous in bacteria yet have a deceptively simple structure. Knowing how they operate and the purpose of variations in signalling structure is helpful to our understanding of cellular biology and the design of synthetic biological circuits. Critical unanswered questions remain about the energy usage and functional benefits of these systems.We sought to improve our understanding of two-component systems by applying a physics-based modelling framework. We found that tracking energy flow through the cell reveals new energy-dependent behaviour in signalling sensitivity, noise filtering, and maximal cell response. We also found that these properties are not strictly dependent on the molecular properties themselves, but from the configuration of the reaction system as a whole.
Model-based deconvolution for DSC-MRI: A comparison of accuracy, precision, and computational complexity of parametric transit time distributions
Authors: Sobhan Rashed , Gkogkou Pinelopi , Johnson Glyn , Cameron Donnie 
Published: February 2023

AbstractObjectDynamic susceptibility contrast MRI (DSC-MRI) is the current standard for cerebral perfusion estimation. Model-dependent approaches for DSC-MRI analysis involve assuming a parametric transit time distribution (TTD) to characterize the passage of contrast agent through tissue microvasculature. Here we compare the utility of four TTD models: namely, skewed-Gaussian, gamma, gamma-variate, and Weibull, to identify the optimal TTD for quantifying brain perfusion.Materials and MethodsDSC-MRI data were acquired in nine subjects at 1.5T, and normal-appearing white- and gray-matter signals were assessed. TTDs were compared in terms of: goodness-of-fit, evaluated using RMSE; noise sensitivity, assessed via Monte-Carlo-simulated noisy conditions; and fit stability, quantified as the proportion of total fits converging to the global minimum. Computation times for model-fitting were also calculated.ResultsThe gamma TTD showed higher fit stability, shorter computation times (p<0.008), and higher robustness against experimental noise as compared to other models. All functions showed similar RMSEs and the parameter estimates (p>0.008) were congruent with literature values.DiscussionThe gamma distribution represents the most suitable TTD for perfusion analysis. Moreover, due to its robustness against noise, the gamma TTD is expected to yield more reproducible estimates than the other models for establishing a standard, multi-center analysis pipeline.
The metaverse as a breakthrough for operations and supply chain management: implications and call for action
Authors: Queiroz Maciel M. , Fosso Wamba Samuel , Pereira Susana Carla Farias , Chiappetta Jabbour Charbel Jose 
Published: February 2023

PurposeThe metaverse development is in the early stages in most organizations and supply chains. There has been exponential growth in metaverse investments by leading tech and other types of companies and governments worldwide. This article aims to shed light on the topic by providing detailed insights for the operations and supply chain management (O&SCM) community concerning the potential, opportunities and challenges associated with the metaverse.Design/methodology/approachThe authors mapped 15 benefits and 15 challenges regarding metaverse in O&SCM-related fields from the literature, which in turn were empirically tested by a panel with 150 experts from more than 12 countries, from operations and supply chains and with experience in metaverse technologies.FindingsThe authors found notable similarities and differences between metaverse adopters and non-adopters in the O&SCM. Accordingly, some benefits and challenges are expected before and after the implementation, but it's still relevant. In contrast, there are ones that change their importance after the implementation.Research limitations/implicationsFirst, this paper points out the need for an urgent call for action to develop high-quality research on the interplay between metaverse and O&SCM. Second, the metaverse will reshape several established business models by offering new products and services, consequently resulting in the remodeling of O&SCM. Third, our paper provides a call for action to engage the community of scholars and practitioners to consider the metaverse as one of the last frontiers of O&SCM in the digital age.Originality/valueThis paper is one of the first that investigates the metaverse benefits, challenges and expectations in the O&SCM. Also, it provides robust directions by an empirical approach to the metaverse as a new and important research stream for O&SCM and related fields. The authors provide a prospective research agenda that scholars and practitioners could use as a roadmap to capture metaverse opportunities in O&SCM.
Reflections on Sixth form education: a weight worth bearing?
Authors: Coates Lewis 
Published: February 2023

Purpose
The purpose of this paper is to share experiences of attending Sixth Form (SF) and to provide reflections on coping, stress management and support for an underresearched cohort of students in Britain. This will be the first in several papers dedicated to the experiences of Sixth Form (SF) students and the need for more research into this area as well as the exploration of the sources of stress that SF students may face.

Design/methodology/approach
Reflective, narrative first-person approach with supporting literature and own research over the master’s thesis of the author and current PhD research.

Findings
Key reflections are SF education lacks support for students who may feel undersupported. Many things other than academics are occurring in this time of life and can become problematic to the students if not supported. Students experience a myriad of changes across this time period but are left behind the author’s support and revision systems that cater to General Certificate of Secondary Education students but are unable to provide support for SF students.

Social implications
Social implications are focussed on building awareness and research into the support needs and sources of stress for SF students.

Originality/value
This paper is one person’s experience with the institution of SF and the expectations, challenges and sources of stress that the author experienced. This paper contributes to the exploration of this underresearched cohort of students.
Facies‐constrained transdimensional amplitude versus angle inversion using machine learning assisted priors
Authors: Dhara Arnab , Sen Mrinal K. , Biswas Reetam 
Published: February 2023

ABSTRACTWe present a methodology for seismic inversion that generates high‐resolution models of facies and elastic properties from pre‐stack data. Our inversion algorithm uses a transdimensional approach where, in addition to the layer properties, the number of layers is treated as unknown. In other words, the data itself determine the correct model parameterization, that is, the number of layers. The reversible jump Markov Chain Monte Carlo method is an effective tool to solve such transdimensional problems as it generates models of reservoir properties along with uncertainty estimates. However, current implementations of the reversible jump Markov Chain Monte Carlo algorithms do not account for the non‐Gaussian and multimodal nature of model parameters. The target elastic reservoir properties generally have multimodal and non‐parametric distribution at each location of the model. The number of modes is equal to the number of facies. Taking these factors into account, we extend the reversible jump Markov Chain Monte Carlo algorithm to simultaneously invert for discrete facies and continuous elastic reservoir properties. The proposed extension to the algorithm iteratively samples the facies, by moving from one mode to another, and elastic properties by sampling within the same mode. The integration of facies classification within the inversion reduces non‐uniqueness, improves convergence speed and produces geologically consistent results. The workflow uses machine learning to generate probabilistic priors for the model parameters. We validate our approach by applying it to a synthetic dataset generated from a well log with two facies and then to a complex synthetic two‐dimensional model involving three facies having overlapping elastic property distribution. Finally, we apply our algorithm to a field dataset acquired over an unconventional reservoir. Our algorithm demonstrates the usefulness of incorporating facies information in seismic inversion and also the feasibility of inverting for facies from seismic data.
Fixing big government or feeding private contractors? Empirical evidence from the case of municipal solid waste management
Authors: Park Seejeen , Moon M. Jae 
Published: February 2023

AbstractThe assumption of new public management (NPM) that governments can lower costs and improve service quality through a market mechanism, such as competition, has been under debate over several decades. To test the NPM assumption, this study investigates the effects of contracting out on cost savings by analysing municipal solid waste management data collected in 25 local governments in the Republic of Korea over a period of 14 years. Contrary to the NPM assumption, this study suggests that contracting out does not necessarily result in cost savings but rather causes additional financial burden on citizens.Points for practitioners
Government officials are strongly encouraged to critically review market‐based managerial reforms.
Government officials need to assess both benefits and costs of contracting‐out practices prior to any outsourcing or privatisation decisions.
Government officials need to make evidence‐based policy decisions and long‐term financial implications from the perspective of citizens.
Pillar 2: tax competition in low‐income countries and substance‐based income exclusion
Authors: Perry Victoria J. 
Published: February 2023

AbstractPillar 2 of the OECD's global tax reform proposal will have significant direct and indirect impacts for low‐income developing countries (LICs). Most interesting and problematic is the question as to how the global anti‐base erosion (GloBE) rules for a proposed global minimum effective tax will affect tax competition behaviour in LICs, and how LICs should respond when a critical mass of higher‐income economies adopt the new structure. Most LICs are source‐only countries, and they are very much in competition to attract foreign direct investment. Do LICs want to continue to compete using the tax system to the extent possible, to step back from that competition, or to take some intermediate course? Pillar 2 does not itself change a country's desired position on the competition spectrum – it merely affects how, and to what extent, that position can still be obtained. This paper posits that LICs should adopt qualified domestic minimum top‐up taxes, and that this will not itself have a negative impact on their competitiveness. The primary focus of the paper, however, is on the design of the substance‐based income exclusion (carve‐out), examining the following three questions. Should the GloBE have been designed without a carve‐out? Would there have been a better way of designing it? How will LICs be affected? The paper concludes that, as little real advantage is likely to accrue to LICs from intangible assets, minimising tax competition for those assets will have relatively little impact on them; and that, from an economic efficiency standpoint, shifting the tax burden away from a normal return and toward economic rents – albeit imperfectly – is a reasonable solution.
Nectar compounds impact bacterial and fungal growth and shift community dynamics in a nectar analog
Authors: Mueller Tobias G. , Francis Jacob S. , Vannette Rachel L. 
Published: February 2023

AbstractFloral nectar is frequently colonised by microbes. However, nectar microbial communities are typically species‐poor and dominated by few cosmopolitan genera. One hypothesis is that nectar constituents may act as environmental filters. We tested how five non‐sugar nectar compounds as well as elevated sugar impacted the growth of 12 fungal and bacterial species isolated from nectar, pollinators, and the environment. We hypothesised that nectar isolated microbes would have the least growth suppression. Additionally, to test if nectar compounds could affect the outcome of competition between microbes, we grew a subset of microbes in co‐culture across a subset of treatments. We found that some compounds such as H2O2 suppressed microbial growth across many but not all microbes tested. Other compounds were more specialised in the microbes they impacted. As hypothesised, the nectar specialist yeast Metschnikowia reukaufii was unaffected by most nectar compounds assayed. However, many non‐nectar specialist microbes remained unaffected by nectar compounds thought to reduce microbial growth. Our results show that nectar chemistry can influence microbial communities but that microbe‐specific responses to nectar compounds are common. Nectar chemistry also affected the outcome of species interactions among microbial taxa, suggesting that non‐sugar compounds can affect microbial community assembly in flowers.
Incremental expenditures attributable to daily dispensation and witnessed ingestion for opioid agonist treatment in British Columbia: 2014–20
Authors: Nosyk Bohdan , Kurz Megan , Guerra‐Alejos Brenda Carolina , Piske Micah , Dale Laura , Min Jeong Eun 
Published: February 2023

AbstractBackground and aimWhile daily witnessed opioid agonist treatment (OAT) ingestion is common in British Columbia (BC), Canada, and elsewhere, sparse evidence supports this resource‐intensive practice. Many settings across North America relaxed restrictions for take‐home dosing during the COVID‐19 pandemic and have reported consistent or improved patient outcomes. This study measured excess expenditures attributed to daily witnessed pharmacy dispensing compared with weekly or biweekly dispensation schedules.Design, setting and participantsThis study was a population‐level retrospective analysis. We included all methadone, buprenorphine/naloxone and slow‐release oral morphine dispensations in BC from 1 January 2014 to 30 December 2020. A total of 24 357 107 OAT dispensations among 51 195 unique individuals with 122 793 person‐years of follow‐up were included during the study period.MeasurementsTotal expenditures for each person‐week of OAT with an estimated expenditure under two scenarios are as follows: (1) a weekly dispensation scenario and (2) a biweekly dispensation scenario.FindingsWe estimated excess expenditures attributable to current dispensing practices of between $38 million (2014) and $47.4 million (2018) compared with a hypothetical weekly dispensing schedule, and $43.9 million (2014) to $54.9 million (2018) compared with biweekly dispensing. The majority of these expenditures (58–64%) were attributed to pharmacy dispensing fees ($23 million in 2014 to $30 million in 2018 compared with weekly dispensing; $26.6 million in 2014 to $34.7 million in 2018 compared with biweekly dispensing).ConclusionDaily witnessed opioid agonist treatment ingestion results in more than $30 million in excess expenditures annually in the province of British Columbia, Canada compared with the costs of weekly or biweekly dispensation schedules.
Systematic review of isolated disseminated carcinomatosis of bone marrow from colorectal cancer
Authors: Chan Wai Kiu , Lin Norman Sihan , Tay Kon Voi , Teo Li‐Tserng 
Published: February 2023

AbstractBackgroundColorectal cancer (CRC) metastasis commonly occurs in the liver and lungs with bone metastasis rarely occurring in isolation. Disseminated carcinomatosis of bone marrow (DCBM) is extremely rare in CRC. We conducted a systematic review to provide more information on the diagnosis, treatment options, and prognosis of the condition.MethodsStudies were identified by performing searches on MEDLINE and EMBASE electronic databases according to the PRISMA statement standards. We included a single patient whom we treated for metastatic CRC presenting with DCBM in our study. Statistical analysis was performed using SPSS software version 23.0.ResultsA search through 5502 unique studies yielded 14 studies that were eventually included. There was a total of 17 cases of DCBM in CRC with back pain and constitutional symptoms as the most common presenting complaints. DCBM in CRC was associated with markedly elevated CEA of 275.57 (95% CI 17.13–534.00). There was no predilection for site of primary tumour. Overall median survival was 120 days (95% CI 64.43–175.58). The median survival for patients who received chemotherapy was 240 days (95% CI 71.11–408.89), as compared to 9 days (95% CI 1.80–16.20) for patients who received best supportive treatment.ConclusionDCBM from CRC is extremely rare. Bone marrow examination remains the gold standard for diagnosis. Colonic stenting or surgical diversion may be more appropriate than primary resection in obstructed CRC in view of the poor prognosis. Systemic chemotherapy shows promise in increasing median survival.
Evaluation of two rapid commercial assays for detection of Streptococcus agalactiae from vaginal samples
Authors: Koliwer‐Brandl Hendrik , Nil Ahmed , Birri Jana , Sachs Maike , Zimmermann Roland , Zbinden Reinhard , Balsyte Dalia 
Published: February 2023

AbstractIntroductionStreptococcus agalactiae, also known as group B streptococci (GBS), is associated with invasive infections in neonates. Identification of GBS vaginal colonization in pregnant women before delivery is essential for treatment with antibiotics to prevent intrapartum vertical transmission to the newborn. This study was designed to evaluate applicability of two rapid real‐time PCRs in comparison to standard culture identification.Material and methodsWe compared the Xpert GBS assay, hereafter referred to as Xpert, and GenomEra GBS PCR, hereafter referred to as GenomEra. The standard culture identification consisted of two different agar plates as well as an enrichment broth.ResultsWe analyzed vaginal samples of 260 pregnant women; 42 samples were tested GBS‐positive by using standard culture as a gold standard, 30 by Xpert, and 37 by GenomEra. Xpert and GenomEra assays performed with sensitivities of 71.4% and 88.1% as well as specificities of 98.6% and 99.1%, respectively. Twelve vaginal samples were false‐negative by Xpert and five samples by GenomEra. Interestingly, three negative Xpert results of standard culture‐positive samples exhibited high Ct‐values indicating the presence of GBS. If higher Ct‐values are taken into consideration, the sensitivity of Xpert increases up to 78.6%. Moreover, only three Xpert PCRs had to be repeated, whereas two Genomera were invalid even after repetition and further 15 GenomEra PCRs were repeated because of borderline results or inhibition of the PCR test.ConclusionsIn this study, GenomEra assay performed with a higher sensitivity than the Xpert PCR. On the other hand, the Xpert assay needs less hands‐on‐time for a sample preparation and requires approximately four‐fold less repetitions as compared to the GenomEra assay. This robust performance of the Xpert assay make it applicable as a rapid intrapartum point‐of‐care test, although a higher sensitivity would be desirable. Therefore, culture in the 35–37 week of gestation remains the gold standard to detect vaginal colonization.
IgG antispike persistence and immunophenotype in children infected by SARS‐CoV‐2
Authors: García‐Salido Alberto , Flores‐Pérez Patricia , González‐Murillo África , Sánchez‐Marcos Elena , Leoz‐Gordillo Inés , Cano‐Fernández Julia , Castillo‐Robleda Ana , Nieto‐Moro Montserrat , Jiménez‐García Raquel 
Published: February 2023

AbstractAimThe immune status of children recovering from SARS‐CoV‐2 infection is not completely understood. We describe IgG antispike persistence in children infected during the first two pandemic waves. In addition, we compared with healthy controls their leukocyte populations and CD64 expression.MethodsCross‐sectional study. Carried out from October 2021 to February 2022 in nonreinfected and nonvaccinated children with SARS‐CoV‐2 in 2020. The presence of antispike IgG was studied using chemiluminescent immunoassay. Leukocyte populations were analysed using flow cytometry and marked for CD45, CD4, CD8 and CD64. Statistical minor than 0.05 was considered significant.ResultsOne hundred and eighty‐three control and 77 patients were included. IgG antispike determinations were performed after a median of 501 days (262–464); 52 of 77 children were positive. Cases showed significantly higher percentages of monocytes, lymphocytes, CD8+ and CD4+. In addition, CD64 expression was higher in monocytes and neutrophils. The presence of IgG antispike was accompanied by a higher percentage of CD64+ neutrophils.ConclusionIn our series, the SARS‐CoV‐2 IgG antispike protein was usually positive beyond 1 year after infection. Furthermore, leukocyte populations from cases differ from controls, with higher CD64 expression on neutrophils and monocytes. Prospective clinical observations are required to confirm the implications of these findings.