Azimuthal asymmetry in ground-based GPS slant delay observations and their NWP model counterparts

International audienceThe ground-based measurements of the Global Positioning System (GPS) allow estimation of the tropospheric delay along the slanted signal paths through the atmosphere. The meteorological exploitation of such slant delay (SD) observations relies on the hypothesis of azimuthal asymmetry of the information content. This article addresses the validity of the hypothesis. The asymmetric properties of the SD observations and their model counterparts are investigated. In this study, the model counterparts are based on 3-h forecasts of a numerical weather prediction (NWP) model, run with four different horizontal resolutions. The SD observations are compared with their model counterparts with emphasis on cases of high asymmetry in order to see whether the observed asymmetry is a real atmospheric signature. The asymmetric delay component is found to be of the order of a few parts per thousand of the absolute SD value, thus barely exceeding the assumed standard deviation of the SD observation error. However, the observed asymmetric delay components show a statistically significant meteorological signal. Benefit of the asymmetric SD observations is therefore expected to be taken in future, when NWP systems will explicitly represent the small-scale atmospheric features revealed by the SD observations

Asymmetricity of ground-based GPS slant delay data

International audienceThe ground-based measurements of the Global Positioning System (GPS) allow estimation of the tropospheric delay along the slanted signal paths through the atmosphere. The meteorological exploitation of such slant delay (SD) observations relies on the hypothesis of azimuthal asymmetry of the information content. This article addresses the validity of the hypothesis. A new concept of asymmetricity is introduced for studying the SD observations and their model counterparts. The asymmetricity is defined as the ratio of the absolute asymmetric delay component to total SD. The model counterparts are determined from 3-h forecasts of a numerical weather prediction (NWP) model, run with four different horizontal resolutions. The SD observations are compared with their model counterparts with emphasis on cases of high asymmetricity in order to see whether the observed asymmetry is a real atmospheric signature. The asymmetricity is found to be of the order of a few parts per thousand. Thus, the asymmetric delay component barely exceeds the assumed standard deviation of the SD observation error. However, the observed asymmetric delay components show a statistically significant meteorological signal. Benefit of the asymmetric SD observations is therefore expected to be taken in future, when NWP systems will explicitly represent the small-scale atmospheric features revealed by the SD observations

Prenatal Growth and CKD in Older Adults : Longitudinal Findings From the Helsinki Birth Cohort Study, 1924-1944

Background: According to the Developmental Origins of Health and Disease (DOHaD) hypothesis, several noncommunicable diseases, including hypertension, type 2 diabetes, and coronary heart disease, have their origins in early life. Chronic kidney disease (CKD) has traditionally been assumed to develop as the result of an interaction between genetic and environmental factors, although more recently, the importance of factors present early in life has been recognized. Study Design: Longitudinal birth cohort study. Setting & Participants: 20,431 people born in 1924 to 1944 in Helsinki, Finland, who were part of the Helsinki Birth Cohort Study were followed up through their life course from birth until death or age 86 years. Predictor: Prenatal growth and socioeconomic factors. Outcomes: Death or hospitalization for CKD. Results: Smaller body size at birth was associated with increased risk for developing CKD. Each standard deviation higher birth weight was associated with an HR for CKD of 0.82 (95% CI, 0.74-0.91; P <0.001). Associations with ponderal index at birth, placental weight, and birth length were also statistically significant (P <0.001, P <0.001, and P = 0.002, respectively), but only among men. Prematurity also predicted increased risk for CKD. Limitations: The study was restricted to people who were born in Helsinki in 1924 to 1944. Conclusions: Smaller body size at birth was associated with increased risk for developing CKD in men. Prematurity was also associated with increased risk for CKD in women. These findings in the Helsinki Birth Cohort Study support the importance of early life factors in the development of CKD.Peer reviewe

Metabarcoding successfully tracks temporal changes in eukaryotic communities in coastal sediments

Metabarcoding is a method that combines high-throughput DNA sequencing and DNA-based identification. Previously, this method has been successfully used to target spatial variation of eukaryote communities in marine sediments, however, the temporal changes in these communities remain understudied. Here, we follow the temporal changes of the eukaryote communities in Baltic Sea surface sediments collected from two coastal localities during three seasons of two consecutive years. Our study reveals that the structure of the sediment eukaryotic ecosystem was primarily driven by annual and seasonal changes in prevailing environmental conditions, whereas spatial variation was a less significant factor in explaining the variance in eukaryotic communities over time. Therefore, our data suggests that shifts in regional climate regime or large-scale changes in the environment are the overdriving factors in shaping the coastal eukaryotic sediment ecosystems rather than small-scale changes in local environmental conditions or heterogeneity in ecosystem structure. More studies targeting temporal changes are needed to further understand the long-term trends in ecosystem stability and response to climate change. Furthermore, this work contributes to the recent efforts in developing metabarcoding applications for environmental biomonitoring, proving a comprehensive option for traditional monitoring approaches.Peer reviewe

The Age of Artificial Intelligence: Use of Digital Technology in Clinical Nutrition

Purpose of review Computing advances over the decades have catalyzed the pervasive integration of digital technology in the medical industry, now followed by similar applications for clinical nutrition. This review discusses the implementation of such technologies for nutrition, ranging from the use of mobile apps and wearable technologies to the development of decision support tools for parenteral nutrition and use of telehealth for remote assessment of nutrition. Recent findings Mobile applications and wearable technologies have provided opportunities for real-time collection of granular nutrition-related data. Machine learning has allowed for more complex analyses of the increasing volume of data collected. The combination of these tools has also translated into practical clinical applications, such as decision support tools, risk prediction, and diet optimization. Summary The state of digital technology for clinical nutrition is still young, although there is much promise for growth and disruption in the future

Serum copper-to-zinc-ratio and risk of incident infection in men : the Kuopio Ischaemic Heart Disease Risk Factor Study

Infections are one of the main causes of mortality in elderly due to the decrease of immune response, for which copper (Cu) and zinc (Zn) are claimed to be crucial. High serum copper-to-zinc-ratio (Cu/Zn-ratio) has been reported with infections, but little is known whether it could also predict the incidence of infections. The study cohort consisted of 1975 men aged 42-60 years and free of severe infectious disease at baseline in 1984-1989 from the prospective population-based Kuopio Ischaemic & xfeff; Heart Disease Risk Factor Study. The main outcome was an incident infection leading to hospitalization. Cox proportional hazards regression models were used for statistical analysis. During the average follow-up of 19.2 years, 636 incident first cases of infections were diagnosed. The hazard ratio (HR) of developing an incident infectious disease in the highest compared to the lowest Cu/Zn-ratio quartile after adjustment for age and baseline examination year was 1.35 [95% confidence interval (CI) = 1.07-1.69, P-trend across quartiles = 0.005]. The association was slightly attenuated after additional adjustment for potential confounders (HR = 1.21, 95% CI = 0.96-1.53, P-trend = 0.054). Furthermore, higher serum Cu concentration was associated with higher risk of an incident infection. The multivariable-adjusted HR was 1.39 (95% CI = 1.10-1.75, P-trend = 0.005) in the highest versus the lowest serum Cu quartile. Serum Zn concentration was not associated with the risk (multivariable-adjusted extreme-quartile HR = 0.83, 95% CI = 0.67-1.04, P-trend = 0.218). In conclusion, our data suggest that an increased Cu/Zn-ratio and especially serum Cu concentration are associated with increased risk of incident infections in middle-aged and older men in Eastern Finland.Peer reviewe

In vitro dissolution methods for hydrophilic and hydrophobic porous silicon microparticles

Porous silicon (PSi) is an innovative inorganic material that has been recently developed for various drug delivery systems. For example, hydrophilic and hydrophobic PSi microparticles have been utilized to improve the dissolution rate of poorly soluble drugs and to sustain peptide delivery. Previously, the well-plate method has been demonstrated to be a suitable in vitro dissolution method for hydrophilic PSi particles but it was not applicable to poorly wetting hydrophobic thermally hydrocarbonized PSi (THCPSi) particles. In this work, three different in vitro dissolution techniques, namely centrifuge, USP Apparatus 1 (basket) and well-plate methods were compared by using hydrophilic thermally carbonized PSi (TCPSi) microparticles loaded with poorly soluble ibuprofen or freely soluble antipyrine. All the methods showed a fast and complete or nearly complete release of both model compounds from the TCPSi microparticles indicating that all methods described in vitro dissolution equally. Based on these results, the centrifuge method was chosen to study the release of a peptide (ghrelin antagonist) from the THCPSi microparticles since it requires small sample amounts and achieves good particle suspendability. Sustained peptide release from the THCPSi microparticles was observed, which is in agreement with an earlier in vivo study. In conclusion, the centrifuge method was demonstrated to be a suitable tool for the evaluation of drug release from hydrophobic THCPSi particles, and the sustained peptide release from THCPSi microparticles was detected

Serum n-6 polyunsaturated fatty acids and risk of atrial fibrillation : the Kuopio Ischaemic Heart Disease Risk Factor Study

Purpose N-6 polyunsaturated fatty acids (PUFA), particularly linoleic acid (LA), have been associated with lower risk of coronary heart disease (CHD), but little is known about their antiarrhythmic properties. We investigated the association of the serum n-6 PUFAs with the risk of atrial fibrillation (AF), the most common type of cardiac arrhythmia. Methods The study included 2450 men from the Kuopio Ischaemic Heart Disease Risk Factor Study, aged 42-60 years at baseline. The total n-6 PUFA includes linoleic acid (LA), arachidonic acid (AA), gamma-linolenic acid (GLA) and dihomo-gamma-linolenic acid (DGLA). Cox proportional hazards regression was used to estimate hazard ratio (HR) of incident events. Results During the mean follow-up of 22.4 years, 486 AF cases occurred. The multivariable-adjusted HR in the highest versus the lowest quartile of total serum n-6 PUFA concentration was 0.79 (95% CI 0.58-1.08, P trend = 0.04). When evaluated individually, only serum LA concentration was inversely associated with AF risk (multivariable-adjusted extreme-quartile HR 0.69, 95% CI 0.51-0.94, P trend = 0.02). These associations were stronger among the men without history of CHD or congestive heart failure at baseline, compared to men with such disease history (P for interaction = 0.05 for total n-6 PUFA and LA). Similar associations were observed with dietary LA and AA intakes. No significant associations were observed with serum AA, GLA or DGLA concentrations. Conclusions Higher circulating concentration and dietary intake of n-6 PUFA, mainly LA, are associated with lower risk of AF, especially among men without history of CHD or congestive heart failure.Peer reviewe