bluuebunny/crossref_metadata_2025_split huggingface dataset:
Subexponential Parameterized Algorithms and Kernelization on Almost Chordal Graphs
Authors: Fomin Fedor V. , Golovach Petr A. 
Published: April 2021

AbstractWe study algorithmic properties of the graph class $${\textsc {Chordal}}{-ke}$$

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, that is, graphs that can be turned into a chordal graph by adding at most k edges or, equivalently, the class of graphs of fill-in at most k. It appears that a number of fundamental intractable optimization problems being parameterized by k admit subexponential algorithms on graphs from $${\textsc {Chordal}}{-ke}$$

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. More precisely, we identify a large class of optimization problems on $${\textsc {Chordal}}{-ke}$$

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solvable in time $$2^{{\mathcal{O}}(\sqrt{k}\log k)}\cdot n^{{\mathcal{O}}(1)}$$

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. Examples of the problems from this class are finding an independent set of maximum weight, finding a feedback vertex set or an odd cycle transversal of minimum weight, or the problem of finding a maximum induced planar subgraph. On the other hand, we show that for some fundamental optimization problems, like finding an optimal graph coloring or finding a maximum clique, are FPT on $${\textsc {Chordal}}{-ke}$$

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when parameterized by k but do not admit subexponential in k algorithms unless ETH fails. Besides subexponential time algorithms, the class of $${\textsc {Chordal}}{-ke}$$

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graphs appears to be appealing from the perspective of kernelization (with parameter k). While it is possible to show that most of the weighted variants of optimization problems do not admit polynomial in k kernels on $${\textsc {Chordal}}{-ke}$$

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graphs, this does not exclude the existence of Turing kernelization and kernelization for unweighted graphs. In particular, we construct a polynomial Turing kernel for Weighted Clique on $${\textsc {Chordal}}{-ke}$$

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graphs. For (unweighted) Independent Set we design polynomial kernels on two interesting subclasses of $${\textsc {Chordal}}{-ke}$$

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, namely, $${\textsc {Interval}}{-ke}$$

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and $${\textsc {Split}}{-ke}$$

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graphs.
HAG1 and SWI3A/B control of male germ line development in P. patens suggests conservation of epigenetic reproductive control across land plants
Authors: Genau Anne C. , Li Zhanghai , Renzaglia Karen S. , Fernandez Pozo Noe , Nogué Fabien , Haas Fabian B. , Wilhelmsson Per K. I. , Ullrich Kristian K. , Schreiber Mona , Meyberg Rabea , Grosche Christopher , Rensing Stefan A. 
Published: April 2021

Abstract
Key message
Bryophytes as models to study the male germ line: loss-of-function mutants of epigenetic regulators HAG1 and SWI3a/b demonstrate conserved function in sexual reproduction.

Abstract
With the water-to-land transition, land plants evolved a peculiar haplodiplontic life cycle in which both the haploid gametophyte and the diploid sporophyte are multicellular. The switch between these phases was coined alternation of generations. Several key regulators that control the bauplan of either generation are already known. Analyses of such regulators in flowering plants are difficult due to the highly reduced gametophytic generation, and the fact that loss of function of such genes often is embryo lethal in homozygous plants. Here we set out to determine gene function and conservation via studies in bryophytes. Bryophytes are sister to vascular plants and hence allow evolutionary inferences. Moreover, embryo lethal mutants can be grown and vegetatively propagated due to the dominance of the bryophyte gametophytic generation. We determined candidates by selecting single copy orthologs that are involved in transcriptional control, and of which flowering plant mutants show defects during sexual reproduction, with a focus on the under-studied male germ line. We selected two orthologs, SWI3a/b and HAG1, and analyzed loss-of-function mutants in the moss P. patens. In both mutants, due to lack of fertile spermatozoids, fertilization and hence the switch to the diploid generation do not occur. Pphag1 additionally shows arrested male and impaired female gametangia development. We analyzed HAG1 in the dioecious liverwort M. polymorpha and found that in Mphag1 the development of gametangiophores is impaired. Taken together, we find that involvement of both regulators in sexual reproduction is conserved since the earliest divergence of land plants.
Dispersal and colonization risk of the Walnut Twig Beetle, Pityophthorus juglandis, in southern Europe
Authors: Marchioro Matteo , Faccoli Massimo 
Published: April 2021

AbstractThe Walnut Twig Beetle (WTB),Pityophthorus juglandisBlackman, is a small bark beetle native to Mexico and Southwestern USA recorded for the first time in Europe (NE Italy) in 2013. WTB attacks walnut (Juglansspp.) and wingnut trees (Pterocaryaspp.) and is the vector ofGeosmithia morbidaKolarík et al., a pathogen causing the thousand cankers disease (TCD). WTB and TCD represent a serious threat for walnut orchards in Europe. Spatiotemporal data of the WTB-TCD infestations recorded from an 8-year-long (2013–2020) monitoring conducted in 106 walnut orchards of NE Italy were used to develop a model in order to analyze: (i) the effective dispersal capacity of WTB, (ii) the factors affecting dispersal and (iii) the colonization risk of healthy walnut orchards. We registered a mean annual dispersal of 9.4 km, with peaks of about 40 km. Pest dispersal is affected by distance of suitable hosts from the nearest infested site, number of walnut orchards in the surroundings (both infested and healthy), orchard size and walnut species in the orchard. Using the model, it was also possible to calculate the colonization risk of a specific walnut orchard according to its characteristics showing, for instance, that a medium-size (5,000 trees) black walnut orchard located at 25 km from the nearest infested orchard has an infestation risk of about 50% of probability.
Time trends of perfluoroalkyl substances in blood in 30-year old Norwegian men and women in the period 1986–2007
Authors: Berg Vivian , Sandanger Torkjel Manning , Hanssen Linda , Rylander Charlotta , Nøst Therese Haugdahl 
Published: April 2021

AbstractBiomonitoring studies are helpful tools and can increase our knowledge on time trends in human blood concentrations of PFASs: how they relate to emission trends and the potential prenatal exposure for future generations. In this study, serum was sampled in cross-sections of men and women who were 30 years old in each of the years 1986, 1994, 2001, and 2007 in Northern Norway and analyzed for 23 PFASs. Differences in serum concentrations across sampling years were investigated graphically and with significance testing and compared with those observed in our previous longitudinal study using repeated individual measurements in older men in the same years. The results demonstrate overall increasing blood burdens of PFASs in men and women in reproductively active ages during 1986–2001 and decreases until 2007. However, longer chained PFASs were still increasing in 2007 indicating divergent time trends between the different PFASs, underlining the importance of continued biomonitoring. Comparisons between 30-year-old men and older men within the same population demonstrated variation in time trends in the exact same years, underlining that biomonitoring studies must regard historic exposures and birth cohort effects.
Potential interplay of Uranium with geochemical variables and mineral saturation states in groundwater
Authors: Chandrasekar Thivya , Sabarathinam Chidambaram , Viswanathan Prasanna Mohan , Rajendiran Thilagavathi , Mathivanan Mahalakshmi , Natesan Devaraj , Samayamanthula Dhanu Radha 
Published: April 2021

AbstractUranium (U) is formed by the interaction of groundwater in aquifer and the surrounding rocks. The area chosen for this study is a hard rock terrain of various lithology in South India, which releases U in groundwater and affect the groundwater quality. Hence, this study was conducted to understand the geochemistry and temporal variations of U in groundwater with respect to saturation state of minerals for different seasons namely Pre-monsoon (PRM), Northeast monsoon (NEM), Southwest monsoon (SWM) and Post-monsoon (POM). A total of 216 groundwater samples were collected, representing various lithology (Fissile hornblende biotite gneiss, Charnockite, Quartzite, Granite and Flood Plain Alluvium) in the study area. The collected samples were analyzed for physical parameters such as Electrical conductivity, Total dissolved solids, pH and major ions. U was measured using Laser Fluorimeter. The study infers that weathering in SWM, ion exchange in PRM and POM and anthropogenic process in NEM were the three major processes that could dominate the hydrogeochemistry of U. The higher concentration of U has been highlighted, and the water–rock interaction has been studied to know the sources of origin and it has been plotted through bivariate and ternary diagrams. The saturation index study was made and calculated for uranium, carbonate, sulfate, silicate and phosphate minerals using PHREEQC Programme. Uraninite and Coffinite are the dominant saturated states of U minerals which tend to attain near saturation to saturation state irrespective of seasons. With the increase in U concentration irrespective of seasons, it was noticed that the saturation state of minerals is also increasing. Overall, the weathering process and the lithological impact are the sources for higher concentration of U and their minerals occurring in the study area. The outcome of the study will help the policy makers for sustainable management to safeguard the groundwater resource in this region.
Chlorpromazine affects the numbers of Sox-2, Musashi1 and DCX-expressing cells in the rat brain subventricular zone
Authors: Skałbania Jakub , Pałasz Artur , Błaszczyk Iwona , Suszka-Świtek Aleksandra , Krzystanek Marek , Tulcanaz Karina Paola , Worthington John J. , Mordecka-Chamera Kinga 
Published: April 2021

Abstract
Background
Adult neurogenesis observed both in the subventricular zone (SVZ) and hippocampus may be regulated and modulated by several endogenous factors, xenobiotics and medications. Classical and atypical antipsychotic drugs are able to affect neuronal and glial cell proliferation in the rat brain. The main purpose of this structural study was to determine whether chronic chlorpromazine treatment affects adult neurogenesis in the canonical sites of the rat brain. At present, the clinical application of chlorpromazine is rather limited; however, it may still represent an important model in basic neuropharmacological and toxicological studies.

Methods
The number of neural progenitors and immature neurons was enumerated using immunofluorescent detection of Sox2, Musashi1 and doublecortin (DCX) expression within SVZ.

Results
Chlorpromazine has a depressive effect on the early phase of adult neurogenesis in the rat subventricular zone (SVZ), as the mean number of Sox-2 immunoexpressing cells decreased following treatment.

Conclusion
Collectively, these results may suggest that long-term treatment with chlorpromazine may decrease neurogenic stem/progenitor cell formation in the rat SVZ and may affect rostral migratory stream formation.
Measuring Progress of Regulatory Convergence and Cooperation Among Asia–Pacific Economic Cooperation (APEC) Member Economies in the Context of the COVID-19 Pandemic
Authors: Chong Sannie Siaw Foong , Kim Mirinea , Limoli Michelle , Obscherning Eric , Wu Patricia , Feisee Lila , Nakashima Nobumasa , Lim John C. W. 
Published: April 2021

Abstract
Purpose
Regulatory convergence and cooperation among medical product regulatory authorities are essential to delivering safe and efficacious products quickly to patients. The COVID-19 pandemic highlights the urgent need for streamlined regulatory approval processes—which can be achieved in part through regulatory convergence and cooperation—both to accelerate availability of COVID-19 vaccines, treatments and diagnostics and to maintain the availability of the existing medical products unrelated to COVID-19.

Methods
The Asia–Pacific Economic Cooperation (APEC) Life Sciences Innovation Forum (LSIF) established the Regulatory Harmonization Steering Committee (RHSC) in 2008 to advance regulatory convergence among APEC’s 21 member economies. Key performance indicators (KPIs) were developed in 2018 to measure convergence.

Results
This paper reports survey results collected from KPI tracking in March 2020 from medical product regulatory authorities in all 21 APEC economies concerning areas of regulatory practice in which they could converge and cooperate. For example, from 2008 to 2020, there was a 14.3% increase in the number of APEC member economy regulatory authorities sharing Good Manufacturing Practices (GMP) Certificates and a 28% increase in the number of regulatory authorities accepting multisite licenses in that same period. In addition, this paper explores how APEC economies could realize a maximum level of regulatory convergence and cooperation.

Conclusions
Convergence efforts within APEC can accelerate availability of medical products including that related to COVID-19 vaccines, treatments and diagnostics, while maintaining the availability of the existing medical products unrelated to COVID-19 vaccines and treatment. New KPIs and capability building are to be considered to enable a new era of innovation ushered in by COVID-19.
Variance Based Sensitivity Analysis of FLake Lake Model for Global Land Surface Modeling
Authors: Bernus A. , Ottlé C. , Raoult N. 
Published: April 2021

AbstractGiven the ever increasing spatial resolution of climate models and the significant role of lakes on the regional climate, it becomes important to represent water bodies in climate models. Such developments have started in the IPSL (Institut Pierre Simon Laplace) climate model and its land surface component, ORganizing Carbon and Hydrology In Dynamic Ecosystems (ORCHIDEE), with the Freshwater Lake model, FLake. To answer the questions raised by these new developments, such as the lake differentiation and related model parameters, we analyze spatial distributions of lake characteristics in the whole world to perform a global sensitivity analysis of the FLake parameters. As a result, three different climates and four lake depth configurations were selected as test cases. The Sobol method as sensitivity analysis based on variance decomposition was chosen to rank parameters impact on the model output, that is, lake surface water temperature, latent and sensible heat fluxes. We focus on the 11 parameters of the FLake model, which are the lake depth, the albedo and light extinction coefficient of water, snow, and ice respectively, the fetch, and the relaxation coefficient of the thermocline shape factor. The results show different sensitivity features according to the lake type and climate. The dominant role and time varying contribution of the lake depth, radiative parameters (albedo, light extinction coefficient) and thermocline relaxation coefficient linked to the atmospheric conditions, were clearly highlighted. These findings will lead us to distinguish between different lake categories in each grid cell of ORCHIDEE in the future implementation.
Statistically Determining the Spatial Extent of Relativistic Electron Precipitation Events Using 2‐s Polar‐Orbiting Satellite Data
Authors: Gasque L. Claire , Millan Robyn M. , Shekhar Sapna 
Published: April 2021

AbstractRelativistic electron precipitation (REP) from the outer radiation belt into Earth's atmosphere poses risks for satellites and affects Earth's climate, producing ozone‐destroying compounds. Characterizing the spatial extent of REP events, which are periods of precipitation localized in space and time, is important for quantifying these effects and improving understanding of outer radiation belt dynamics, allowing quantification of the relative roles of atmospheric and magnetopause particle loss. Following Shekhar et al. (2017, https://doi.org/10.1002/2017JA024716), who used 16 s resolution data from particle detectors onboard NOAA's Polar‐orbiting Operational Environmental Satellites (POES) and the ESA's Meterological Operational (MetOp) Satellites, we work to more precisely determine the spatial extent of REP events using higher‐resolution (2 s) data from the same instruments. We algorithmically search through 6 years of data (October 2012 to December 2018) from a maximum of seven simultaneously orbiting satellites, identifying REP events and determining their start and end times and locations. We find that the majority of events are highly localized spatially and, unlike Shekhar et al. (2017, https://doi.org/10.1002/2017JA024716), we do not observe a cluster of broad events around midnight magnetic local time (MLT). Based on case studies, we suggest that this discrepancy results from the differences in data resolution, indicating that the broad regions of precipitation around midnight MLT identified by Shekhar et al. (2017, https://doi.org/10.1002/2017JA024716) may be composed of several adjacent but narrowly confined regions of precipitation, potentially with independent causes. Additional work is necessary to further classify events and identify their likely mechanisms.
Targeting Tryptophan for Tagging through Photoinduced Electron Transfer
Authors: Taylor Michael T. , Orellana Norberto V. 
Published: April 2021

AbstractThe chemical modification of tryptophan (Trp) has been the subject of interest for nearly 100 years, yet the development of modification conditions that exploit the inherent photolability of Trp has remained elusive. With this perspective, we discuss our recently reported method for Trp photobioconjugation that uses N-carbamoyl pyridinium salts to engage Trp in photoinduced electron transfer. We detail our inspiration and rationale, and we place our report in the context of selected prior art in the field.1 Introduction2 Light Activation as a Design Principle in Bioconjugation3 Targeting Tryptophan with Light4 Reaction Design and Proof of Concept5 Mechanistic Considerations6 Establishing Mechanistic Control7 Conclusions and Outlook
Race/Ethnic Differences in Atherosclerotic Cardiovascular Disease Risk Factors Among Patients With Hypertension: Analysis From 143 Primary Care Clinics
Authors: Khatib Rasha , Glowacki Nicole , Lauffenburger Julie , Siddiqi Alvia 
Published: April 2021

Abstract

Background
While it is known that sex and race/ethnic disparities persist for atherosclerotic cardiovascular disease (ASCVD), disparities in risk factor control have not been well-described in primary care where ASCVD can be prevented.

Methods
Adult patients with a hypertension diagnosis without ASCVD were included in this analysis of electronic health records from a large US healthcare system from 2018. Patients were categorized based on risk factor control defined as blood pressure (BP) &lt;130/80 mm Hg; statin prescription among patients with indications, HbA1c of &lt;7%, and not smoking. Multivariable Poisson regressions were developed to explore associations with race/ethnicity. Results are presented as relative risk (RR), 95% confidence intervals (CIs).

Results
Among 5,227 patients, 55.8% women and 60.0% men had uncontrolled BP, 47.3% women and 46.4% men with statin therapy indication did not have a prescription, 34.9% women and 40.9% men had uncontrolled HbA1c values, and 9.3% women and 13.7% men were smokers. African Americans were more likely to have uncontrolled BP (women: RR 1.18, 95% CI 1.07–1.30; men: RR 1.20, 95% CI 1.05–1.34) and more likely to lack a statin prescription (women: RR 1.23, 95% CI 1.05–1.45; men: RR 1.25, 95% CI 1.03–1.51) compared to Caucasians. Differences in HbA1c control were not statistically significant among Hispanic/Latino compared to Caucasians (women: RR 1.28, 95% CI 0.86–1.90; men: RR 1.20, 95% CI 0.72–1.97).

Conclusions
Disparities in controlling ASCVD risk factors in primary care persist and were not fully explained by demographic or clinical characteristics. Monitoring changes in disparities is important to ensure equity as interventions to prevent ASCVD in primary care are developed and implemented.
Energy political ecologies in the South Pacific: the politics of energy transitions in Vanuatu
Authors: Munro Paul G 
Published: April 2021

Abstract
In this article, I develop a political ecology analysis of Vanuatu’s grid electricity policies, with a specific focus on Espiritu Santo Island. I show how the global political economy looms large in shaping the island’s energy geographies. Colonial legacies, ideologically conflictive donor aid programmes, multinational corporate legal discords, parliamentary political caprices and the vicissitudes of the local environment all intersect to shape the spatial dynamics of electricity access that raises numerous energy justice concerns. The development of the island’s electricity infrastructure is not neutral; rather, it is a socio-technical product of these political economy mediations.
The Effect of a Consumer-Based Activity Tracker Intervention on Accelerometer-Measured Sedentary Time Among Retirees: A Randomized Controlled REACT Trial
Authors: Suorsa Kristin , Leskinen Tuija , Pulakka Anna , Pentti Jaana , Löyttyniemi Eliisa , Heinonen Ilkka , Vahtera Jussi , Stenholm Sari 
Published: April 2021

AbstractBackgroundEffective strategies to reverse the increasing trend of sedentary behavior after retirement are needed. The aim of this study was to examine the effect of 12-month activity tracker-based intervention on daily total and prolonged sedentary time (≥60 minutes) among recent retirees.MethodsRandomization to intervention and control groups was performed to 231 retirees (mean age 65.2 [SD 1.1] years, 83% women). Intervention participants wore a consumer-based wrist-worn activity tracker (Polar Loop 2, Polar, Kempele, Finland), including daily activity goal, every day and night for 12 months. The activity tracker also gave vibrating reminders to break up uninterrupted inactivity periods after 55 minutes. A wrist-worn triaxial ActiGraph wGT3X-BT accelerometer was used to measure sedentary time at baseline and at 3-, 6-, and 12-month time points.ResultsThe use of an activity tracker did not reduce daily total or prolonged sedentary time over 12 months (p values for time * group interaction 0.39 and 0.27, respectively). In the post hoc analysis focusing on short- and medium-term effects on prolonged sedentary time, no differences between the intervention and control groups over 3 months were found, but a tendency for a greater decrease in prolonged sedentary time in the intervention group over 6 months was seen (mean difference in changes between the groups 29 minutes, 95% CI −2 to 61).ConclusionsThe activity tracker with inactivity alerts did not elicit changes in sedentary time over 12 months among recent retirees. Alternative approaches may be needed to achieve long-term changes in sedentary time among retirees.Clinical Trials registration Number: NCT03320746