Primary Measurement Research Articles

Lake-wide measurements of primary productivity in Lake Erie

Abstract Few lake-wide, seasonal primary production measurements have been made in Lake Erie. None more recent than 1997 have been reported in the literature. In 2019 we used 13C uptake to measure production at 11 stations across the lake during three surveys in May, July, and September and at four of these stations during two additional surveys in April and August. Samples were collected at two depths (2 m and 6 m) and incubated on deck using eight levels of irradiance. We fit the resultant photosynthesis-irradiance curves with models that included the initial slope at low light levels, the maximum photosynthesis rate at light saturation, and when warranted, the negative slope at high irradiance. During May, there was little variation in chlorophyll-normalized volumetric productivity with sample depth, and productivity generally was higher nearshore and in the western basin than it was offshore. The distinction between nearshore and offshore stations was less pronounced in July, but nearshore productivity was higher than offshore in September. Using the photosynthesis data from all five surveys, chlorophyll concentration profiles, and estimated clear-sky solar insolation, we calculated time series of vertically integrated daily production at a western basin station, two central basin stations, and an eastern basin station. Central basin production was highest during August, estimated to be 748 mg C m-2 d-1 and 779 mg C m-2 d-1 at our two stations. Production peaked in July in the western basin (510 mg C m-2 d-1) and September in the eastern basin (421 mg C m-2 d-1). Whole-lake seasonal areal phytoplankton photosynthesis was estimated as 1.661E6 tonnes, about half of estimates made in the 1990s using 14C methods. These results inform our understanding of spatial-temporal trends in Lake Erie productivity and highlight the need for continued measurements of Lake Erie primary production.

Parenting Styles And Their Impact On Online Gaming Addiction: Mediating Role Of Psychological Well-Being In Indonesia

In Indonesia’s distinctive cultural and digital milieu, this study explores the interconnectedness between parenting styles, psychological well-being, and online game addiction in individuals aged 15-30. Utilizing digital outreach on platforms such as Instagram, Twitter, and Facebook, data was sourced from 601 participants. The Indonesian Online Game Addiction Questionnaire, the Parental Authority Questionnaire (PAQ), and Triwahyuni and Prasetio’s 42-item scale for psychological health were the primary measurement tools. Findings underscore an inverse relationship between both paternal and maternal parenting styles and psychological health. Furthermore, psychological well-being serves as a critical mediator in the relationship between parenting styles and online gaming habits. The insights offer significant implications for parenting, psychological health, and digital gaming behaviors in the contemporary Indonesian context, suggesting a need for harmonized approaches that seamlessly blend tradition and modern challenges.

Pancreatic Cyst Size Measurement on Magnetic Resonance Imaging Compared to Pathology.

While multiple cyst features are evaluated for stratifying pancreatic intraductal papillary mucinous neoplasms (IPMN), cyst size is an important factor that can influence treatment strategies. When magnetic resonance imaging (MRI) is used to evaluate IPMNs, no universally accepted sequence provides optimal size measurements. T2-weighted coronal/axial have been suggested as primary measurement sequences; however, it remains unknown how well these and maximum all-sequence diameter measurements correlate with pathology size. This study aims to compare agreement and bias between IPMN long-axis measurements on seven commonly obtained MRI sequences with pathologic size measurements. This retrospective cohort included surgically resected IPMN cases with preoperative MRI exams. Long-axis diameter tumor measurements and the presence of worrisome features and/orhigh-risk stigmata were noted on all seven MRI sequences. MRI size and pathology agreement and MRI inter-observer agreement involved concordance correlation coefficient (CCC) and intraclass correlation coefficient (ICC), respectively. The presence of worrisome features and high-risk stigmata were compared to the tumor grade using kappa analysis. The Bland-Altman analysis assessed the systematic bias between MRI-size and pathology. In 52 patients (age 68 ± 13 years, 22 males), MRI sequences produced mean long-axis tumor measurements from 2.45-2.65 cm. The maximum MRI lesion size had a strong agreement with pathology (CCC = 0.82 (95% CI: 0.71-0.89)). The maximum IPMN size was typically observed on the axial T1 arterial post-contrast and MRCP coronal series and overestimated size versus pathology with bias +0.34 cm. The radiologist interobserver agreement reached ICCs 0.74 to 0.91 on the MRI sequences. The maximum MRI IPMN size strongly correlated with but tended to overestimate the length compared to the pathology, potentially related to formalin tissue shrinkage during tissue processing.

International comparison of measurements of neutron source emission rate (2016-2021) - CCRI(III)-K9.Cf.2016

Main textSection III (neutron measurements) of the Comité Consultatif des Rayonnements Ionisants, CCRI, conducted a comparison of primary measurements of the neutron emission rate of a 252Cf radionuclide source. A single 252Cf source was circulated to all participants between 2016 and 2020. Ten laboratories participated -CMI (Czech Republic), KRISS (Republic of Korea), IRD/LNMRI (Brazil), LNE-LNHB (France), NIM (China), NIST (USA), NMIJ (Japan), NPL (UK), NRC (Canada) and VNIIM (Russia) - with NPL making their measurements at the start and repeating them at the end of the exercise to verify the 250Cf content of the source. Each laboratory reported the emission rate into 4π sr together with a detailed uncertainty budget. All participants used the manganese bath technique except NMIJ who used a relative method based on measurements with a 3He detector in a graphite pile. VNIIM also made measurements using an associated particle technique. CMI, KRISS, LNE-LNHB, NIM, NPL and VNIIM also measured the anisotropy of the source although this did not formally form part of the comparison.To reach the main text of this paper, click on Final Report. Note that this text is that which appears in Appendix B of the BIPM key comparison database https://www.bipm.org/kcdb/.The final report has been peer-reviewed and approved for publication by the CCRI, according to the provisions of the CIPM Mutual Recognition Arrangement (CIPM MRA).

Final report of APMP.AUV.V-S1: supplementary comparison on calibration of laser tachometers using mechanical generators

Main textThis is the final report for APMP supplementary comparison APMP.AUV.V-S1 in the area of 'vibration' (quantity of rotational speed). The aim of this comparison was to compare primary measurements of rotational speed in the range from 10 r/min to 99 999 r/min. Two Metrology Institutes from APMP have participated in the comparison with National Institute of Metrology, P.R. China as pilot lab. Both laboratories used mechanical generators as standard equipment and provided their calibration results, which were all consistent within their declared expanded uncertainties for the measurement results except for 10 r/min. Both participants contributed to the SCRVs calculated for thirteen rotational speed comparison values. NMC was not consistent within their declared expanded uncertainties at 10 r/min. Further improvements of their calibration devices and uncertainty evaluations will provide more accurate and reliable measurement results in the future.To reach the main text of this paper, click on Final Report. Note that this text is that which appears in Appendix B of the BIPM key comparison database https://www.bipm.org/kcdb/.The final report has been peer-reviewed and approved for publication by the CCAUV, according to the provisions of the CIPM Mutual Recognition Arrangement (CIPM MRA).

Final report of APMP.AUV.V-S2: supplementary comparison on calibration of laser tachometers using mechanical generators or optical simulators

Main textThis is the final report for APMP supplementary comparison APMP.AUV.V-S2 in the area of 'vibration' (quantity of rotational speed). The aim of this comparison was to compare primary measurements of rotational speed in the range from 30 r/min to 99 996 r/min. Six Metrology Institutes from two RMOs, APMP and AFRIMETS, have participated in the comparison with the National Institute of Metrology, P.R. China as the pilot lab. NIM, NMC and NIS used a mechanical generator for calibration, with expanded uncertainties in the order from 10-3 to 10-5. NML, NIMT and KEBS used an optical simulator for calibration, with expanded uncertainties in the order from 10-4 to 10-5. All the participating laboratories provided their calibration results, which were all consistent within their declared expanded uncertainties for the measurement results. Each participant contributed to the SCRVs calculated for five rotational speed comparison values of two laser tachometers, NLYZ-02 and 03, except that NIS's measurement results of NLYZ-03 are invalid. Smaller measurement uncertainties than the order of 10-5 for the calibration of laser tachometers are difficult to achieve for either mechanical generators or optical simulators with the current technology of rotational speed standard devices and laser tachometers.To reach the main text of this paper, click on Final Report. Note that this text is that which appears in Appendix B of the BIPM key comparison database https://www.bipm.org/kcdb/.The final report has been peer-reviewed and approved for publication by the CCAUV, according to the provisions of the CIPM Mutual Recognition Arrangement (CIPM MRA).

Settlement prediction of shallow foundations for quality controls of sandy hydraulic fills

This paper describes a procedure for settlement prediction of shallow foundations on carbonate sands, but it is fully applicable and valid for siliceous sands. For practical purposes, the design of shallow foundations resting on medium dense and dense granular soils is typically governed by limiting settlement to tolerable values. Predicting foundation settlement is therefore important, but in standard practice it is necessarily based on indirect (and therefore often conservative) determinations of soil compressibility (or modulus), due to the intrinsic difficulties in obtaining direct measurements.While numerical analyses incorporating non-linear soil behaviour may be a preferred method for computing expected total and differential settlement of shallow foundations of given geometry and stiffness on sand under static loading, the method described in this paper consists of a simplified and expeditious method based on equivalent linear elasticity. The method uses: i) the elastic soil stiffness profile at small strain, E0(z) obtained from the shear wave velocity as the primary measurement of deformability and ii) the reduction in modulus as a function of strain magnitude, E(ε) to account for stiffness non-linearity. The beneficial effect on the soil initial stiffness of the applied footing load is also considered. The method was developed as an on-site tool for checking the compaction of hydraulic fills made of carbonate sand to form artificial islands, but its application can be extended to other natural and anthropogenic coarse-grained materials.

Service flow changes in multilayer networks: A framework for measuring urban disaster resilience based on availability to critical facilities

Failures of roads and critical facilities under disasters can result in public service disruptions. Studies quantifying disaster resilience commonly focus on evaluating physical performance of infrastructure systems, often cannot capture their capacity that maintain available service to meet citizens’ demands. This paper proposes a flow-based framework for quantitively measuring resilience by regarding changes in service availability to critical facilities as a primary measurement outcome. Through the utilization of multilayer networks, we effectively incorporate diverse datasets pertaining to population demographics, residential areas, critical facilities, and the roadway network. This integration enables us to simulate the intricate dynamics of public service flows within dynamic urban systems, thereby evaluating resilience levels and accurately mapping the spatial distribution patterns. The methodology was validated in Shanghai by quantifying regional variations in healthcare services under pluvial flood scenarios. The research findings highlight the heterogeneous redistribution of service flows during extreme events, leading to spatial variations in resilience outcomes, irrespective of the proximity to hazard-prone areas. The spatial clustering of vulnerable communities demonstrates a close association with mobility correlation patterns, which are strongly influenced by the distribution of facilities and the connectivity of the road network. Thus, using the framework offers valuable insights into risk mitigation and planning of critical facilities in extreme situations. It enhances the understanding on how urban resilience to disaster is influenced by urban form and flow interactions, generating robust evidence for policy.

Efficacy of Virtual Reality Exposure Therapy in the Treatment of Specific Phobias: A Systematic Review

Specific phobia is defined as a notable and continuous fear of a certain object or a situation that particularly impairs daily life and functioning. It is also one of the most common psychological disorders. Exposure-based interventions are commonly used in the treatment of specific phobias. However, some limitations of the standard methods require the need for alternative approaches. In light of this, the use of virtual reality technology in psychotherapy has become increasingly widespread in recent years and is now integrated with exposure therapy. Virtual reality provides real-time interaction using the computer-generated three-dimensional environment via variety oftechnological tools. Applications of virtual reality in exposure therapy have proven to be an important intervention method, especially in the psychopathologies such as specific phobias. In this study, virtual reality exposure therapy for the treatment of specific phobias is systematically reviewed. Inclusion criteria were taken into account in the scanning performed in APA (PsycINFO), EBSCO, PubMed, Scopus, Web of Science, Science Direct, Ulakbim ve TRDizin databses following the PRISMA method. Following that, ten randomized controlled trials, which included adult participants meeting the diagnostic criteria for specific phobia, examined the efficacy of virtual reality and exposure therapy compared to the control group, and the ones with full text could be accessed, were included in this systematic review. The included studies were evaluated in terms of sample attributes, primary measurement tools, research design, characteristics of the intervention and its efficacy. In general, the findings indicate the efficacy of virtual reality exposure therapy in reducing specific phobia symptoms. Follow-up studies support the long-term maintenance of the results.

Microbial ecology and activity of snow algae within a Pacific Northwest snowpack

ABSTRACT Snow algae blooms are common occurrences in alpine systems and contribute to increasing snow and glacial ice melt rates. Despite the cosmopolitan distribution of snow algae, little is known about the role their life cycle plays in community composition and activity in snowpack. Mount Baker, in Washington, USA, is a rapidly changing alpine ecosystem. Here we present estimates of cellular biomass, microbial community composition, and primary productivity measurements associated with surficial snow algae blooms and a vertical profile within a snow pit to characterize the microbial ecology of this snowpack system. Chloromonas was the most abundant algae detected in our samples. Sphingobacteriaceae were the most dominant bacteria in samples where fungi were the most abundant eukaryote, whereas Chitinophagaceae dominated when Chlorophyceae were the most abundant eukaryote. In a snow pit vertical profile, we observed more algae in the green-pigmented, flagellated life cycle stage at depth (~30 cm below the surface) than at the surface where the astaxanthin-rich, aplanospore life cycle stage dominated. Higher resolution analyses revealed that Chloromonas-associated photosynthesis transcripts were more abundant at depth than at the surface of the snowpack. These results suggest that there is a photosynthetic niche within alpine snowpack that has unknown effects on the carbon budget and provides potentially undetected primary productivity resulting in a “cryptic” photosynthetic system.

End of Affirmative Action-Who Is Impacted Most? Analysis of Race and Sex Among US Internal Medicine Faculty.

For over 50 years, the United States (US) used affirmative action as one strategy to increase diversity in higher education including medical programs, citing benefits including training future public and private sector leaders. However, the recent US Supreme Court ending affirmative action in college admissions threatens advancements in the diversity of medical college faculty. Our study evaluated the demographic trends in Internal Medicine (IM) faculty in the US by assessing sex and race/ethnicity diversity to investigate who is likely to be impacted most with the end of affirmative action. Longitudinal retrospective analysis SUBJECTS: IM faculty from the Association of American Medical Colleges faculty roster from 1966 to 2021 who self-reported sex and ethnicity MAIN OUTCOMES: The primary study measurement was the annual proportion of women and racial/ethnic groups among IM faculty based on academic rank and department chairs. Although racial/ethnic diversity increased throughout the era of affirmative action, African American, Hispanic, and American Indian populations remain underrepresented. White physicians occupied > 50% of faculty positions across academic ranks and department chairs. Among the non-White professors, Asian faculty had the most significant increase in proportion from 1966 to 2021 (0.6 to 16.6%). The percentage of women increased in the ranks of professor, associate professor, assistant professor, and instructor by 19.5%, 27.8%, 25.6%, and 26.9%, respectively. However, the proportion of women and racial/ethnic minority faculty decreased as academic rank increased. Despite an increase in the representation of women and racial/ethnic minority IM faculty, there continues to be a predominance of White and men physicians in higher academic ranks. With the end of affirmative action, this trend has the danger of being perpetuated, resulting in decreasing diversity among IM faculty, potentially impacting patient access and health outcomes.

Infrared temperature measurements on fast moving targets: A novel calibration approach

In this study, an infrared system is developed for accurate measurements of surface temperature and heat transfer on fast moving targets. The system was designed for the Oxford Turbine Research Facility, a world-leading experimental facility delivering highly engine representative, scalable heat transfer results for aerospace research. Infrared thermography is employed to acquire temperature maps of high-pressure turbine blades, allowing assessment of surface thermal conditions including heat transfer coefficient, adiabatic wall temperature, Nusselt number, cooling effectiveness, and metal effectiveness.Achieving accurate infrared thermography measurements in rotating turbomachinery experimental conditions is arduous due to reflections from the surroundings, low emissivity of metallic parts, and motion blur resulting from high speed. To overcome these challenges, calibration procedures were developed against a traceable standard using a bespoke steady experimental facility. A method to determine the reflected temperature from surroundings was also validated. Correction for all measurement disturbances is demonstrated to within the accuracy of the primary measurement thermocouple.Finally, the developed calibration method was validated on a fast-moving rotating geometry demonstrating accurate correction for all measurement disturbances, without the need for an in situ calibration. A detailed uncertainty analysis for each calibration step is also presented.

Damage mechanism and failure risk analysis of offshore pipelines subjected to impact loads from falling object, considering the soil variability

Trench and burial, as a primary and effective protection measurement for offshore pipelines from impact loads, has received much research attention recently. Previous studies were usually performed based on the assumption that the soil material was homogeneous with deterministic mechanical properties. The soil spatial variability, which is demonstrated to have significant influences on the soil capacity in marine geotechnical analysis, has not been included. This study was motivated to investigate the response of the buried pipelines subjected to the impact loads, with special address on the soil variability. Firstly, a three-dimensional random large deformation finite element analysis model was developed, which was implemented by the field variable (FV) technique to map the non-stationary random field (NSRF) into the verified Coupled Eulerian-Lagrangian (CEL) model (Hereafter referred to as FVRCEL). Then the FVRCEL model was integrated with the Monte-Carlo simulation (MCS) to obtain the statistical characteristics of the pipeline structural response. The failure mechanisms of the pipeline in the random soil with different fluctuation scales were investigated, and a parametric study was performed to identify the influential factors. Finally, the failure probability curves and surfaces were presented, providing clues for the pipeline safety design. The results revealed that in general, more than 50 % of the realized NSRF scenarios in the random analysis yielded more severe dent damage than the deterministic result, indicating that the latter would underestimate the damage degree, which was more pronounced when the increasing gradient of soil strength was high. The horizontal fluctuation scale had a remarkable influence on the pipeline damage behaviours and the corresponding statistical characteristics, of which the inner mechanisms were discussed. From the probabilistic perspective, at most an extra failure probability of 75 % would be suffered if the soil variability was ignored.

Effects of different nutrient loadings on planktonic primary production in embayments of Indonesia

A study on planktonic primary production was conducted in three Indonesian embayments subjected to different levels of eutrophication. The three embayments are Jakarta, Lampung and Semangka Bay. A previous study revealed that Jakarta Bay is heavily eutrophied while Lampung Bay is moderately eutrophied and Semangka Bay is close to pristine conditions. The eutrophication state in the three bays studied was closely related with respective nutrient loading of the embayments. Annual primary production in Jakarta Bay ranged from 47 to 503 g C m-2 y-1, in Lampung Bay from 31 to 196 g C m-2 y-1 and in Semangka Bay from 14 to 40 g C m-2 y-1. Spatial gradients in primary productivity were closely related to spatial nutrient gradients in the bays, except in Semangka Bay, due to the high turbidity of the river mouth. Temporal variability in primary productivity was small, consistent with small changes in environmental parameters across seasons. Jakarta Bay which has the most eutrophied waters was the highest in terms of primary productivity, followed by Lampung Bay and Semangka Bay. The primary productivity levels in the three bays was closely related with levels of nutrient loadings. This research is of importance for the development of primary production measurement in Indonesia since it is among that uses the radiocarbon technique.

A Carbon Nanocomposite Material Used in the Physical Modelling of the Overburden Subsidence Process.

Carbon nanomaterial is widely used in structural health monitoring due to the advantage of sensitivity and good mechanical properties. This study presents a novel approach employing carbon nanocomposite materials (CNMs) to characterize deformation and damage evolution in physical modelling. As the primary measurement method, the CNM is used to investigate the deformation characteristics of a 200-400 m thick sandstone bed at a 1 km deep longwall mine. The sandstone unit is identified as an ultra-thick key stratum (UTKS), with its thicknesses varying across different mining panels of the UTKS. The results of CNM monitoring show that the UTKS remains stable even after a consecutive excavation of 900 m in width. This stability impedes the upward propagation of overlying strata failure, leading to minimal surface subsidence. The study demonstrates the huge potential of CNM in the mining area, which can be useful for investigating material damage in physical modelling studies. The findings suggest that the cumulative extraction width in individual mining areas of the mine should be controlled to avoid a sudden collapse of the UTKS, and that special attention should be paid to where the UTKS's thickness changes substantially. The substantial variation in UTKS thickness significantly impacts the pattern of overburden subsidence.

Integrating extraction framework and methods of individual tree parameters based on close-range photogrammetry

The forest plots survey's primary measurement factors are the diameter at breast height (DBH), tree height, and the individual tree volume. The reconstruction of a 3D forest scene based on dense images can contribute to the automatic extraction of individual tree parameters. Close-range photogrammetry (CRP) can achieve the reconstruction of a 3D scene from the sequence images at a highly efficient and low cost. However, the reconstructed point clouds often miss the trees' upper part, resulting in the tree height and volume not being measured directly. This paper proposes an integrating extraction framework and methods of the DBH, tree height, and individual tree volume for achieving automatic measurement of the individual tree parameters with high accuracy based on CRP. Four plantation plots in Wangyedian Forest Farm, Inner Mongolia, and Gaofeng Forest Farm, Guangxi Zhuang, are selected to obtain sequence close-up photographs and construct 3D scenes. The DBH, tree height, and trunk volume of the individual tree are extracted using circle fitting, stem curve fitting, growth equation, and segmentation measurement. The extracted individual tree parameters from Terrestrial laser scanning (TLS) are used as validation data to evaluate the accuracy. It shows a good performance in two Larix gmelinii plots, one Pinus tabulaeformis plot, and one Eucalyptus grandis plot with the accuracy of extracted DBH above 90%, which is 90.18%, 96.54%, 90.17%, and 95.00%, respectively. The accuracy of extracted tree height of the four plots is all above 85%, which is 93.34%, 91.71%, 90.32%, and 85.96%, respectively, and the accuracy of trunk volume is 91.55%, 91.94%, 89.86%, and 89.6%, respectively. The results show that our proposed integrated parameter extraction frame and methods can achieve high accuracy economically, efficiently, and conveniently, and be used for automatic measurements of individual tree factors in forest plot surveys.

The Impact of the COVID-19 Pandemic in The Netherlands on Primary Healthcare Use and Clinical Outcomes in Persons with Type 2 Diabetes

The COVID-19 pandemic has had a significant impact on healthcare systems worldwide, including the postponing or canceling of appointments and procedures for type 2 diabetes (T2D) care by general practitioners (GPs) in the Netherlands. The aim of this study was to investigate the impact of the COVID-19 pandemic on primary healthcare use and clinical measurements for people with T2D. Additionally, we aimed to determine if changes were observed among specific risk groups: (1) persons 70 years or older, or below 70 years, (2) patients who were meeting their HbA1c targets and those who were not, and (3) patients with high-risk and non-high-risk T2D. This retrospective cohort study among persons with T2D was conducted using data from the DIAbetes MANagement and Treatment (DIAMANT) data infrastructure, deriving data from electronic medical records of Dutch GPs. The study assessed GP visit counts, and counts and values of clinical measurements, including hemoglobin A1c (HbA1c), body mass index (BMI), low-density lipoprotein (LDL) cholesterol, and systolic blood pressure (SBP). Adjusted negative binomial (NB) regression and generalized estimating equations (GEE) models were used to estimate GP visit counts and population averages of clinical measurements, respectively, comparing 2019 (pre-pandemic) with 2020 (during the pandemic). Changes in specific groups were examined by stratifying outcomes for the aforementioned subgroups. The cohort consisted of 182,048 patients with T2D (47% female, mean age 69 ± 13 years) on 1 March 2019, of which 168,097 persons (92%) still contributed follow-up data in 2020. We observed an increase in total GP visits in 2020, with an adjusted rate ratio (RR) of 1.09 (95% CI 1.08–1.09). The frequency increased for office visits (RR 1.06; 1.06–1.07) and phone calls (RR 1.33; 1.31–1.35) but remained stable for home visits (RR 1.02; 0.99–1.04). On both population and individual levels, HbA1c values increased in 2020 by 1.65 (1.59–1.70) mmol/mol compared to 2019. Observed changes in 2020 for BMI, LDL, and SBP values were also statistically significant but small. Subgroup stratifications showed higher scores of all clinical measurements in younger persons (<70 years), those who met their HbA1c target, and non-high-risk T2D patients than their respective high-risk subgroups. During the first year of the COVID-19 pandemic in the Netherlands, changes in primary healthcare use were observed among persons with T2D, with an increase in GP office visits and phone calls and a decreased number of clinical measurements and GP home visits. HbA1c levels increased among patients with T2D in 2020. Further research is necessary to determine the impact of the COVID-19 pandemic on long-term clinical outcomes and (long-term) T2D complications.

GPS-SBAS-Based Orbit Determination for Low Earth Orbiting Satellites

A space-based augmentation system (SBAS) provides real-time GNSS correction signals via geostationary satellites for near-ground GNSS users. To use the SBAS correction for low Earth orbit (LEO) satellites, the correction, especially the ionosphere correction, must be adjusted for the LEO altitude. We apply modified SBAS data to LEO satellite onboard navigator to improve the positioning accuracy of a LEO satellite for possible real-time use. The onboard navigator requires high positioning reliability, and code pseudoranges, rather than phase pseudoranges, are used for the primary measurements. The Galileo NeQuick G model is used to determine the real-time conversion factor of the SBAS ionosphere correction for a LEO satellite. The GPS L1 data from GRACE satellite are combined with the SBAS data from the ground receiver. The onboard navigator combines the precise satellite dynamic model with an extended Kalman filter to improve positioning accuracy and stability. The kinematic positioning method, which uses the weighted least square method without the dynamic model, is also performed for comparison. The SBAS correction reduces the positioning error in both the kinematic positioning and the dynamic positioning. The positioning error reduction of the GPS and WAAS case over the GPS-only case is 25.2% for the kinematic method and 30.6% for the dynamic method. In the case of the dynamic method with the SBAS corrections, the positioning error remains smaller than that of the GPS-only dynamic method even after the satellite has left the SBAS service area.

Is Obstructive Sleep Apnea-Associated Adenoid Hypertrophy Linked to Scoliotic Attitudes in Children?

Introduction Scoliosis, a multifaceted spinal deformity commonly affecting pediatric and adolescent populations, has spurred extensive scientific inquiry to understand its origins and impacts. Early-onset scoliosis (EOS), characterized by spinal curvature exceeding 10° before the age of 10, presents a unique challenge necessitating a comprehensive understanding of its etiological factors. Within this context, the potential role of hypoxia-induced by adenoid hypertrophy in contributing to the pathogenesis of EOS has emerged as an intriguing avenue of investigation. Materials and methods This retrospective study was conducted focusing on radiological and clinical data pertaining to children below 10 years of age who underwent isolated adenoidectomy for adenoid hypertrophy. Preoperative posteroanterior standing chest radiographs were utilized for scoliosis assessment, with Cobb angles serving as the primary measurement metric. To ensure accuracy and reliability, Cobb angle measurements were independently performed by two experienced observers. Statistical analyses encompassed the Mann-Whitney U test, Spearman correlation analysis, and intraclass correlation coefficient calculations to evaluate interobserver agreement. Results Among the cohort of 218 pediatric adenoidectomy patients, 177 individuals had radiographs suitable for EOS evaluation. The mean age of the participants was 5.72±2 years, with a nearly equal distribution of 52.5% male and 47.5% female patients. Strikingly, the study identified a 10.2% prevalence of coronal plane curvatures exceeding the critical threshold of 10°, indicative of EOS. The robust interobserver reliability was demonstrated by a commendable mean interclass correlation coefficient (ICC) value of 0.926, affirming consistent and accurate Cobb angle measurements between the observers. Conclusion In light of the heightened prevalence of EOS observed in children undergoing adenoidectomy, this study provides a compelling impetus for exploring the potential interrelationship between adenoid hypertrophy, hypoxia, and the emergence of early-onset scoliosis. The study underscores the importance of prospective research to elucidate the complex mechanisms connecting these factors, offering insights into potential risk factors and underlying pathogenic pathways associated with the development of early-onset scoliosis.

A portrait of gestational diabetes mellitus in Brazil: A systematic review and meta-analysis.

The diagnostic criteria for gestational diabetes mellitus (GDM), a transient hyperglycemic state during pregnancy, has varied remarkably over time, resulting in a diversity of prevalence rates. The aim of this systematic literature review was to provide estimates of prevalence rates of GDM in Brazil according to different diagnostic criteria. We identified, reviewed, and extracted data from the scientific literature on studies estimating the prevalence of diabetes in pregnant women living in Brazil. The databases searched were PubMed, LILACS, SciELO, Embase, Web of Science, and Cochrane Library. We grouped studies by the source of information assessing GDM, patients' age, and criteria used to diagnose GDM. When three or more studies were available in a group, we calculated the pooled prevalence. The Joanna Briggs Institute (JBI) appraisal tool was used to assess the risk of bias. The data were reported according to the 2020 PRISMA recommendations. The study protocol was registered in PROSPERO. We identified 1,328 records and selected 21 studies involving 122,635 pregnant women. Studies in adults only, with primary data and laboratory measurements, and using the IADPSG criteria (n = 3) had a GDM prevalence of 18.0% (95% confidence interval [CI]: 16.0-20.1%) and included 6,243 participants. Estimates of self-reported GDM (n = 3; 10,136 participants of all ages) had a pooled GDM prevalence of 2.1% (95% CI: 1.5-5.2%), with high heterogeneity (I2 = 85.0%, p < 0.01). Studies including adolescents had consistently low prevalences. The prevalence of GDM in Brazil varied, was greater when the IADPSG criteria were applied, and depended on the methods used to obtain the GDM information and the age structure of the sample.