Population Studies Research Articles

Populism and alternative models to representative democracy

ABSTRACT This introduction to the special issue provides an overview of the state of the art in the study of populism and democracy. It outlines the current debates and identifies several questions that remain unexplored or underexplored. It elaborates on how the different articles in this special issue address these gaps in the literature in order to advance and consolidate our knowledge about the relationship between populism and alternatives to representative democracy. Those articles make a significant contribution to this debate and open important avenues for future research.

Longitudinal Coadaptation of Older Adults With Wearables and Voice-Activated Virtual Assistants: Scoping Review.

The integration of smart technologies, including wearables and voice-activated devices, is increasingly recognized for enhancing the independence and well-being of older adults. However, the long-term dynamics of their use and the coadaptation process with older adults remain poorly understood. This scoping review explores how interactions between older adults and smart technologies evolve over time to improve both user experience and technology utility. This review synthesizes existing research on the coadaptation between older adults and smart technologies, focusing on longitudinal changes in use patterns, the effectiveness of technological adaptations, and the implications for future technology development and deployment to improve user experiences. Following the Joanna Briggs Institute Reviewer's Manual and PRISMA-ScR (Preferred Reporting Items for Systematic Reviews and Meta-Analyses Extension for Scoping Reviews) guidelines, this scoping review examined peer-reviewed papers from databases including Ovid MEDLINE, Ovid Embase, PEDro, Ovid PsycINFO, and EBSCO CINAHL from the year 2000 to August 28, 2023, and included forward and backward searches. The search was updated on March 1, 2024. Empirical studies were included if they involved (1) individuals aged 55 years or older living independently and (2) focused on interactions and adaptations between older adults and wearables and voice-activated virtual assistants in interventions for a minimum period of 8 weeks. Data extraction was informed by the selection and optimization with compensation framework and the sex- and gender-based analysis plus theoretical framework and used a directed content analysis approach. The search yielded 16,143 papers. Following title and abstract screening and a full-text review, 5 papers met the inclusion criteria. Study populations were mostly female participants and aged 73-83 years from the United States and engaged with voice-activated virtual assistants accessed through smart speakers and wearables. Users frequently used simple commands related to music and weather, integrating devices into daily routines. However, communication barriers often led to frustration due to devices' inability to recognize cues or provide personalized responses. The findings suggest that while older adults can integrate smart technologies into their lives, a lack of customization and user-friendly interfaces hinder long-term adoption and satisfaction. The studies highlight the need for technology to be further developed so they can better meet this demographic's evolving needs and call for research addressing small sample sizes and limited diversity. Our findings highlight a critical need for continued research into the dynamic and reciprocal relationship between smart technologies and older adults over time. Future studies should focus on more diverse populations and extend monitoring periods to provide deeper insights into the coadaptation process. Insights gained from this review are vital for informing the development of more intuitive, user-centric smart technology solutions to better support the aging population in maintaining independence and enhancing their quality of life. RR2-10.2196/51129.

Does seasonal flowering and fruiting patterns of cacao only depend on climatic factors? The case study of mixed genotype populations in Côte d'Ivoire

Theobroma cacao, a tropical cauliflorous fruit tree, typically produces flowers and fruits twice a year and exhibits alternate harvesting patterns over consecutive six-monthly seasons in regions with bi-modal rainfall distribution, such as Côte d'Ivoire. This study investigated seasonal variations in flowering and fruiting among trees in populations of mixed cacao genotypes. The intensities of crown and trunk flowering and pod production were monitored for eight consecutive six-monthly seasons on 114 adult cacao trees grown from seedlings. We investigated distributions of seasonal flowering and fruiting values, relationships between flowering and pod production, and the effects of seasonal cumulative rainfall. The patterns of seasonal flowering and fruiting series were analyzed using two descriptors: the first distinguishing between regular and variable patterns, and the second analyzing the structure of such variability, classifying it as either irregular or alternating. Despite being subjected to similar climate and agronomic management, individual trees exhibited highly variable flowering and fruiting behaviors within each season, as well as variable patterns of flowering and fruiting across seasons. Seasonal alternate fruiting on a population scale masked highly variable patterns among trees, and only 19 % of the trees exhibited marked alternate fruiting patterns. Variations in pod production on a tree scale were mainly related to variations in trunk flowering. Endogenous factors seemed to control seasonal variations in flowering and fruiting, even though exogenous factors, both climatic and agronomic, could structure flowering and fruiting patterns at the orchard scale.

Depression and anxiety in the context of the COVID-19 pandemic: A 6-waves longitudinal study in the Argentine population.

The pandemic has caused stress due to isolation, loss of loved ones, work and learning changes, financial instability, fear of infection, and uncertainty. It has negatively impacted mental health, particularly increasing anxiety, and depression symptoms. This study analyzed anxiety and depression symptoms over the first 25months of the COVID-19 pandemic, considering age group, socioeconomic status, and gender. A longitudinal study with 6 repeated measures was conducted, involving 988 adult participants from Argentina. Adapted versions of the BDI-II and STAI were administered through online questionnaires at 2, 14, 50, 130, 390, and 750days since the start of the lockdown. The results showed a sustained increase in anxiety and depression symptoms up to 390days, followed by a decrease in anxiety below initial levels at 750days. Depressive symptoms significantly decreased after 750days but remained higher than initial levels. Women consistently scored higher than men, lower socioeconomic status individuals reported more symptoms, and younger individuals had higher anxiety and depression, which decreased with age. Surprisingly, older individuals displayed better mental health indicators compared to the rest of the population.

GSTP1-A313G genetic polymorphism and the risk of preeclampsia in pregnant women: A study in the northern population of Iran

Preeclampsia or high blood pressure in pregnancy is one of the special disorders during pregnancy. It seems that oxidative stress plays an important role in the occurrence of this disease. The purpose of this study is to investigate the relationship between the A313G polymorphism in exon five of the glutathione S-transferase gene (GSTP1) and the risk of preeclampsia in a case-control study. In this study, blood samples were collected from 70 healthy pregnant women and 70 women with preeclampsia. After genomic DNA extraction, the PCR-RFLP method was performed to check the genotype in GSTP1-A313G and the genotypic frequencies of AA, AG, and GG were determined in all samples. Also, using bioinformatics software, the effect of the above polymorphism on the protein structure was investigated. Statistical analysis for A313G polymorphism showed that AG (OR: 1.1684, 95 % CI: 0.5877–2.3228, p = 0.657) and GG (OR: 1.3793, 95 % CI: 0.3376–5.6359, p = 0.654) genotypes were not associated with risk of preeclampsia in the population of northern Iran. However, bioinformatic analyzes have shown that this polymorphism does have a destructive effect on the protein structure. However, more studies with larger sample sizes are needed to draw firm conclusions.

Halving of the meniscectomy rate and their costs in Italy: A15-years period analysis.

The purpose of this study was to determine the incidence and hospitalization trends of meniscectomy in Italy from 2001 to 2016. A secondary aim was to investigate the economic burden of the disease on the national healthcare system. Data were extracted from the Italian Ministry of Health's National Hospital Discharge Reports. Diagnoses are coded according to the ICD-9-CM. Meniscectomy was defined by the following main procedure codes: 806, 8026 and 8145. By dividing the number of annual cases by the size of the adult population reported annually by ISTAT, incidence rates were computed. Overall, 1,454,891 meniscectomies were performed in the study period between 2001 and2016. The incidence was 178 procedures for every 100,000 Italian inhabitants. The incidence declined from 202 in 2001 to 106 in 2016. Males were the largest portion of patients undergoing surgery (68.2%). The average age of patients was 46.59 ± 15.07. A decreasing trend inlength of hospital stay was observed over the study period. The annual average cost per 100,000 inhabitants was EUR 491.219 ± 122.148 with a range from EUR 291,500 ± 79.500 in 2016 to EUR 610,500 ± 166.500 in 2004. In Italy, the number of meniscectomies performed in the adult population has almost halved over the study period. Results of the present study in the Italian population seem to reflect how the clinical evidence basis affects surgical technique selection. The economic burden of meniscectomy is relevant in Italy with an estimated expenditure from EUR 181.861.375 to 318.257.406 between 2001 and 2016. Level III.

Impact of thyroid function on coagulation and venous thromboembolism: a two-sample mendelian randomization study.

The association between thyroid function, coagulation and venous thromboembolism (VTE) has been reported in observational studies with conflicting findings. This study aimed to elucidate the causal effects of thyroid function on coagulation and VTE from a genetic perspective. Two sample Mendelian randomization analysis was conducted using summary statistics from genome-wide association studies in a European population. Coagulation status was associated with nine coagulation-related factors (F VIII, F IX, F XI, Fibrinogen, Antithrombin-III, Thrombomodulin, Plasminogen activator inhibitor-1, Protein C and Protein S). Inverse variance weighting with random effect method was used as the main analytic approach with MR-Egger, weighted median, simple mode and weighted mode methods serving as complements. Sensitivity analyses including heterogeneity test, horizontal pleiotropy test and leave-one-out analysis were conducted to further assess the reliability of results. No genetic causal effects of thyroid function on VTE (including pulmonary embolism and deep venous thrombosis) were found. Genetically, hyperthyroidism was suggestively related to decreased Antithrombin-III (β: -0.04 [95% CI: -0.06 to - 0.01], p = 0.010) and Protein C (β: -0.03 [95% CI: -0.06 to 0.00], p = 0.045). No notable associations were observed between other thyroid function parameters and coagulation-related factors. We provide suggestive genetic evidence supporting the causal effect of hyperthyroidism on decreased level of anticoagulant factors including Antithrombin-III and Protein C. However, whether this genetic causality could lead to clinically significant hypercoagulable state and increased risk of VTE in hyperthyroid population needs to be further addressed.

Beneficial effects of short-term breastfeeding versus non-breastfeeding in early life against childhood obesity: findings from the US-based population study NHANES

BackgroundBreastfeeding is widely recognized for its potential to reduce childhood obesity. However, research investigating these benefits in children breastfed for a short duration (up to 6 months) remains limited despite this being a common practice globally.MethodsThis study focused on a population breastfed for 6 months or less to determine the potential benefits of short-term breastfeeding for preventing childhood obesity. Data were collected from five survey cycles of an US-based population study (the National Health and Nutrition Examination Survey (NHANES)), spanning 2009–2020. A sample of 3,211 children aged 2–6 years was selected, including 1,373 never breastfed and 1,838 ever breastfed. Logistic regression analysis examined the direct association between short-term breastfeeding and childhood obesity. Subsequent subgroup analyses were conducted. Additionally, stratified logistic regression explored the relationship between childhood obesity and the introduction of other early nutrition in both ever-breastfed and never-breastfed children.ResultsOverall, breastfeeding for 6 months or less did not directly prevent childhood obesity. However, among participants with older mothers (aged 35 or above), short-term breastfeeding was associated with a lower risk of childhood obesity compared to never being breastfed (OR 0.31, 95% CI: 0.17, 0.59). Similarly, children aged 3–4 years who were breastfed for > 3 ~ 6 months exhibited a lower obesity risk (OR 0.56, 95% CI: 0.35, 0.89). In ever-breastfed children, delayed infant formula introduction was linked to a lower risk of obesity (P-trend < 0.05: introduction at age ≤ 1 vs. >1 ~ 3 vs. >3 months). Conversely, for non-breastfed children, introducing milk (other than breast milk or formula) later (≥ 12 versus < 12 months) and introducing alternatives to whole cow’s milk were associated with lower obesity risks (OR 0.54, 95% CI: 0.37, 0.78; OR 0.21, 95% CI: 0.08, 0.60, respectively). Notably, these trends were not observed in ever-breastfed children.ConclusionsShort-term breastfeeding may offer some benefits in preventing childhood obesity for specific populations. Additionally, it could potentially mitigate risks associated with the introduction of formula and cow’s milk at inappropriate times.

Analyses of the association between Helicobacter pylori antibody titre and pathogenicity before and after eradication: results of the Kyushu and Okinawa population study, a retrospective observational cohort study

ObjectivesTo assess the utility of Helicobacter pylori antibody testing, we evaluated the correlation between the H. pylori antibody titre and H. pylori-associated pathogenicity and the changes in antibody titre after...

Opioids and personalized analgesia in the perioperative setting: A protocol for five systematic reviews.

Treatment with opioids is a mainstay in perioperative pain management. While the leading treatment paradigm has been procedure-specific pain management, efforts regarding personalized pain treatment are increasing. The OPI•AID project aims to develop personalized algorithms for perioperative pain management, taking demographic, surgical, and anaesthesiologic factors into account. We will undertake five parallel reviews to illuminate current evidence on different aspects of individual responses to perioperative opioid treatment. Inclusion of adult populations in English-written studies. Review-specific searches are developed for the following databases: CENTRAL, MEDLINE, Embase, clinicaltrials.gov, and clinicaltrial.eu. Two authors will independently screen citations, extract data, and assess the risks of bias in each review (QUIPS, PROBAST and RoB2, as relevant). These reviews will evaluate various aspects of perioperative opioid treatment, including individualized treatment strategies, selection of specific opioids, and individual patient responses. These will guide future development of a personalized perioperative opioid treatment algorithm (OPI•AID) that will be validated and tested clinically against standard of care.

The Myanmar Version of the Oswestry Disability Questionnaire: A Cross-Cultural Adaptation, Reliability and Validity Study in the Low Back Pain Population

Objective: To translate and cross-culturally adapt the Myanmar version of the Oswestry Disability Questionnaire (M-ODQ), and examine its reliability and validity in the low back pain (LBP) population. Material and Methods: The M-ODQ was cross-culturally adapted in accordance with the ISPOR guidelines for translation. Prefinal testing was done on 20 individuals with LBP, with minor changes. The test-retest reliability, internal consistency, concurrent and construct validity, plus ceiling and floor effects of the M-ODQ were conducted on 101 individuals with LBP, via calculating the intraclass correlation coefficient ICC(2,1), Cronbach’s alpha, and Spearman’s rank correlation coefficient by correlating with the Myanmar version of the Roland-Morris Disability Questionnaire (M-RMDQ), visual analogue scale (VAS), back performance scale (BPS), and the Stark quality of life (QoL) questionnaire. The level of significance was set at p-value&lt;0.05 for all statistical analyses.Results: The test-retest reliability and internal consistency of the M-ODQ showed an ICC(2,1) of 0.91 and a Cronbach’s alpha of 0.703, thus indicating that the M-ODQ had an acceptable level of reliability. A moderate correlation between the M-ODQ and M-RMDQ (rho=0.56); and fair correlation with the VAS (rho=0.253), BPS (rho=0.336), and the physical component of the Stark QoL questionnaire (rho= -0.274) were found. Weak or no correlation was demonstrated with the mental component of the Stark QoL questionnaire (rho= -0.204). No ceiling or floor effects of the M-ODQ occurred in this study. Conclusion: The M-ODQ is a reliable and valid outcome measure for assessing disability among LBP patients in the Myanmar population.

An ecological population study of lampreys in the Lotka-Volterra tertiary trophic level based on sex differences

This study examines the adaptive changes in sex ratio on animal populations and its effects on ecosystem stability and interactions. The effects of sex ratio dynamics on the ecosystem were analyzed through mathematical modeling using lampreys as the study population. In this study, a two-stage tertiary trophic Lotka-Volterra mathematical model of ecological dynamics was developed, taking into account food preferences, ecological roles, and sex interactions of lampreys. The simulation results showed that a rapid adjustment in sex ratio led to a reduction in environmental loads, which triggered an early rebound increase in lampreys and predator populations. To assess the ability of lampreys populations to adjust sex ratios, this study used a combination of fuzzy integrated evaluation and hierarchical analysis methods. The results of the study revealed the importance of sex-adaptive traits for population development, including increased resource utilization efficiency and population fitness, as well as decreased reproductive success and reduced genetic diversity. Based on the RRT (resistance, resilience and temporal stability) method, this study constructed an ecosystem stability assessment model and investigated the effects of changes in the sex ratio of lampreys on ecosystem stability. The experimental results showed that ecosystem stability was highest when the sex ratio was 0.6 and lowest when the sex ratio was 0.2. Variation in sex ratio may affect the behavior and abundance of lampreys, thereby directly influencing their interactions with other species. Variability in sex ratio provides more resources for predators and parasites of lampreys, promotes their growth, and positively affects ecosystem balance. Simulation results showed that the model was highly stable under different interactions. In summary, this study reveals the important effects of sex ratio on ecosystem stability and interactions, and provides important insights into the understanding of adaptive evolutionary traits of species, ecosystem stability and ecological interactions.

Variability and forensic efficiency of 12 X-STR markers in Namibian populations.

STR loci localized on the X chromosome provide information additional to the autosomal markers routinely analyzed in forensic genetics, integrating genetic systems as Y-STRs and mitochondrial DNA in the investigation of complex kinship scenarios and mass disaster cases.In this study we genotyped 12 X-STR loci in 251 male samples from four populations of Namibia in southern Africa using the Investigator Argus X-12 kit (Qiagen, Hilden, Germany). Forensic efficiency parameters indicated high power of discrimination in the considered populations. As part of our investigation, we highlighted partial linkage associations between loci within known linkage groups (LGs) and identified several occurrences of previously unreported out-of-ladder (OL) alleles.Genetic distances between the Namibian populations here investigated and other African (Eritrea, Ethiopia, Somalia, Guinea, Cape Verde) and non-African (Germany, China, Philippines) populations using loci grouped in LGs mirrored their biogeographical distribution differently for each linkage group. Haplotype sharing within each LG revealed a high degree of population-specific types, hinting to the potential of these markers for ancestry applications.These results highlight the importance to produce specific and freely available population databases especially for multi-ethnic countries. This novel dataset is expected to be of interest for population studies that need an accessible reference dataset of African regions not currently well represented, as well as possible relevance for forensic applications focusing on the biogeographic origin of samples.

Assessment of acute neuronal injury in critical illness: prognostication in septic shock patients - preliminary study in a Polish population.

Sepsis-associated brain dysfunction is a common organ dysfunction in sepsis. The main goal of this study was to verify whether the combined assessment of central nervous system injury markers (i.e. S100B, NSE, GFAP) and disease severity as per the Acute Physiology and Chronic Health Evaluation II (APACHE II), Simplified Acute Physiology Score II (SAPS II), and Sequential Organ Failure Assessment (SOFA) classification systems, would increase the accuracy of death prediction in septic shock. Markers of neuronal damage were determined in 55 patients diagnosed with septic shock with no previous neurological disease. Clinical data was collected and the scores on the APACHE II, SAPS II and SOFA prognostic scales were calculated. Death before discharge from the Intensive Care Unit (ICU) was established as the endpoint. Nineteen patients (35%) died before ICU discharge. Patients who died had significantly higher S100B and NSE values, and APACHE II, SAPS II and SOFA scores (P< 0.05 for all). At the time of septic shock diagnosis, NSE levels more accurately predicted the risk of death before ICU discharge than S100B. However, NSE had no better predictive value for short-term mortality than APACHE II, SAPS II and SOFA. Adding C-reactive protein (CRP) and S100B concentrations to the APACHE II score created a predictive model with 95% mortality accuracy (AUC = 0.95; 95%CI 0.85-0.99; P = 0.03). The assessment of acute neuronal injury plays an important role in prognostication in patients with septic shock. The concentration of S100B protein in combination with APACHE II score and concentration of CRP more accurately predicts mortality than the APACHE II alone.

Populist autocratization and populist electoral autocracies: towards a unified conceptual framework

AbstractAlthough the research subjects of populism and autocratization studies are interconnected, the full potential of combining their focuses—the dynamic elements of political systems and institutional dimensions—into a comprehensive and systematic conceptual framework remains underexploited. This study makes a stride in this direction by reviewing and connecting these areas through the concepts of populist autocratization and populist electoral autocracies. These concepts aim to deepen our understanding of the nature of contemporary autocratization and the stability of autocracies. While the study is primarily theoretical-conceptual in nature, it also engages with methodological and operationalization considerations, and outlines a brief research agenda to demonstrate the empirical applicability of the analytical framework and lays the foundation for future research.

The Association of Dietary Inflammatory Index with the Risk of Type 2 Diabetes: A Case-Control Study

Background: The prevalence rate of type 2 diabetes (T2DM) is increasing worldwide, and the role of diet in its etiology has been established. The Dietary inflammatory index (DII) has attracted significant attention in evaluating associations between diet and diseases due to the role of chronic inflammation as an underlying cause of numerous disease processes. Therefore, the relationship between DII score and the risk of T2DM is evaluated in the Iranian population for the first time. Methods: 113 newly diagnosed T2DM patients and 226 apparently disease-free control cases aged 23-59 participated in this case-control study. A valid semi-quantitative food frequency questionnaire was used to assess dietary intake. Then, energy-adjusted DII (E-DII) scores were computed and categorized into quartiles based on values in the population study. A logistic regression model was used to estimate the association between DII and the risk of T2DM after controlling for important potential confounders and effect modifiers. Results: A significant association was observed between E-DII score and T2DM in the crude model (P-trend&lt;0.001), model I (adjusted for physical activity, gender, education level, and family history of T2DM, P-trend&lt;0.001), model II (adjusted for model I + body mass index, P-trend=0.005) (ORquartile4vs1 =2.98 (95% CI: 1.18, 9.12; P= 0.005). Conclusions: A direct association was observed between DII score and the risk of T2D, implying that consuming a more anti-inflammatory diet would help to prevent T2DM. Future longitudinal studies should be conducted to further explore this association.

Prevalence of Juvenile-Onset and Pediatric Huntington’s Disease and Their Availability and Ability to Participate in Trials: A Dutch Population and Enroll-HD Observational Study

Background: Juvenile-onset Huntington’s disease (JHD) represents 1–5% of Huntington’s disease (HD) patients, with onset before the age of 21. Pediatric HD (PHD) relates to a proportion of JHD patients that is still under 18 years of age. So far, both populations have been excluded from interventional trials. Objective: Describe the prevalence and incidence of JHD and PHD in the Netherlands and explore their ability to participate in interventional trials. Methods: The prevalence and incidence of PHD and JHD patients in the Netherlands were analyzed. In addition, we explored proportions of JHD patients diagnosed at pediatric versus adult age, their diagnostic delay, and functional and modelled (CAP100) disease stage in JHD and adult-onset HD patients at diagnosis. Results: The prevalence of JHD and PHD relative to the total manifest HD population in January 2024 was between 0.84–1.25% and 0.09–0.14% respectively. The mean incidence of JHD patients being diagnosed was between 0.85–1.28 per 1000 patient years and of PHD 0.14 per 1.000.000 under-aged person years. 55% of JHD cases received a clinical diagnosis on adult age. At diagnosis, the majority of JHD patients was functionally compromised and adolescent-onset JHD patients were significantly less independent compared to adult-onset HD patients. Conclusions: In the Netherlands, the epidemiology of JHD and PHD is lower than previously suggested. More than half of JHD cases are not eligible for trials in the PHD population. Furthermore, higher functional dependency in JHD patients influences their ability to participate in trials. Lastly, certain UHDRS functional assessments and the CAP100 score do not seem appropriate for this particular group.

Employment of pqqE gene as molecular marker for the traceability of Gram negative phosphate solubilizing bacteria associated to plants.

Insoluble phosphorous compounds solubilization by soil bacteria is of great relevance since it puts available the phosphorus to be used by plants. The production of organic acids is the main microbiological mechanism by which insoluble inorganic phosphorus compounds are solubilized. In Gram negative bacteria, gluconic acid is synthesized by the activity of the holoenzyme glucose dehydrogenase-pyrroloquinoline quinine named GDH-PQQ. The use of marker genes is a very useful tool to evaluate the persistence of the introduced bacteria and allow to follow-up the effect of biotic and abiotic factors on these beneficial microorganisms in the soil. In previous studies we detected the presence of the pqqE gene in a great percentage of both non-culturable and culturable native soil bacteria. The objective of this study was to analyze the phylogeny of the sequence of pqqE gene and its potential for the study of phosphate solubilizing bacteria from pure and mixed bacterial cultures and rhizospheric soil samples. For this, the presence of the pqqE gene in the genome of phosphate solubilizing bacteria that belong to several bacteria was determined by PCR. Also, this gene was analyzed from mixed bacterial cultures and rhizospheric soil associated to peanut plants inoculated or not with phosphate solubilizing bacteria. For this, degenerate primers designed from several bacterial genera and specific primers for the genus Pseudomonas spp., designed in this study, were used. DNA template used from simple or mixed bacterial cultures and from rhizospheric soil samples was obtained using two different DNA extraction techniques. Results indicated that pqqE gene amplification product was found in the genome of all Gram negative phosphate solubilizing bacteria analyzed. It was possible to detect this gene in the DNA obtained from mixed cultures where these bacteria grew in interaction with other microorganisms and in that obtained from rhizospheric soil samples inoculated or not with these bacteria. The phylogenetic analysis indicated that pqqE gene is a conserved gene within related genera. In conclusion, pqqE gene could be a potential marker for the study of phosphate solubilizing bacterial populations.

Genome-wide association study and meta-analysis of phytosterols identifies a novel locus for serum levels of campesterol

Sitosterolemia is a rare inherited disorder caused by mutations in the ABCG5/ABCG8 genes. These genes encode proteins involved in the transport of plant sterols. Mutations in these genes lead to decreased excretion of phytosterols, which can accumulate in the body and lead to a variety of health problems, including premature coronary artery disease. We conducted the first genome-wide association study (GWAS) in the Middle East/North Africa population to identify genetic determinants of plant sterol levels in Qatari people. GWAS was performed on serum levels of β-sitosterol and campesterol using the Metabolon platform from Qatar Biobank (QBB) and genome sequence data provided by Qatar Genome Program. A trans-ancestry meta-analysis of data from our Qatari cohort with summary statistics from a previously published large cohort (9758 subjects) of European ancestry was conducted. Using conditional analysis, we identified two independent single nucleotide polymorphisms associated with β-sitosterol (rs145164937 and rs4299376), and two others with campesterol (rs7598542 and rs75901165) in the Qatari population in addition to previously reported variants. All of them map to the ABCG5/8 locus except rs75901165 which is located within the Intraflagellar Transport 43 (IFT43) gene. The meta-analysis replicated most of the reported variants, and our study provided significant support for the association of variants in SCARB1 and ABO with sitosterolemia. Evaluation of a polygenic risk score devised from European GWAS data showed moderate performance when applied to QBB (adjusted-R2 = 0.082). These findings provide new insights into the genetic architecture of phytosterol metabolism while showing the importance including under-represented populations in future GWAS studies.

VVV catalog of ab-type RR Lyrae in the inner Galactic bulge

Observational evidence has accumulated in recent years, showing that the Galactic bulge includes two populations, a metal-poor one and a metal-rich one, which in addition to having different metallicities show different alpha over iron abundances, spatial distribution, and kinematics. While the metal-rich, barred component has been fairly well characterized, the metal-poor, spheroidal component has been more elusive and harder to describe. RR Lyrae variables are clean tracers of the old bulge component, and they are, on average, more metal-poor than red clump stars. In the present paper, we provide a new catalog of 16488 ab-type RR Lyrae variables in the bulge region within |l|$ and |b|$ extracted from multi-epoch Point Spread Function photometry performed on VISTA Variable in the V\' a L\'actea survey data. We used the catalog to constrain the shape of the old, metal-poor, bulge stellar population. The identification of ab-type RR Lyrae among a large sample of candidate variables of different types has been performed via a combination of a Random Forest classifier and visual inspection. We optimized this process in such a way to extract a clean catalog with high purity, although for this reason its completeness, close to the midplane, is lower compared to a few other near-infrared catalogs covering the same region of the sky. We used the present catalog to derive the shape of their distribution around the Galactic center, resulting in an elongated spheroid with projected axis ratio of b/asim 0.7 and an inclination angle of phi sim 20 degrees. We discuss how observational biases, such as errors on the distances and a nonuniform sampling in longitude, affect both the present measurements and previous ones, especially those based on red clump stars. Because the latter have not been taken into account before, we refrain from a quantitative comparison between these shape parameters and those derived for the main Galactic bar. Nonetheless, qualitatively, taking into account observational biases would lower the estimated ellipticity of the bar derived from red clump stars, and hence reduce the difference with the present results. We publish a high-purity RRab sample for future studies of the oldest Galactic bulge population, close to the midplane. We explore different choices for the period-luminosity-metallicity relation, highlighting how some of them introduce spurious trends of distance with either the period or the metallicity, or both. We provide evidence that they trace a structure that is less elongated than the main bar, though we also highlight some biases of these kind of studies not discussed before.