Weddellhavets hydrografi under SWEDARP 88/89-expeditionen

Etelämantereen rannikolla sijaitseva Weddellinmeri on yksi tärkeimmistä alueista, joilla esiintyy valtamerien syvän veden muodostusta. Syvän veden muodostumisen prosesseihin vaikuttaa merialueen vesikuljetusmekanismit ja ilmastolliset olosuhteet. Tämän opinnäytetyön ensisijainen tavoite on laskelmallisesti arvioida Weddellinmeren virtausoloja ja laskea vesimassojen ominaisuuksien muutoksia. Tähän tarkoitukseen käytettiin SWEDARP 88/89-tutkimusretken aikana kerättyjä hydrografisia mittauksia. Opinnäytetyön ensimmäinen osa käsittää kirjallisuustutkimuksen Weddellinmeren fysikaalisista olosuhteista. Tutkimuksessa kuvataan Weddellinmeren kiertoliikettä, sitä sääteleviä olosuhteita sekä näistä seuraavia alueelle ominaisia merifysikaalisia prosesseja. Lounaisen Weddellinmeren asemaverkon datoja käyttäen tehtiin kuljetuslaskelmia geostrofisten menetelmien avulla. Ensin määriteltiin barokliininen virtauskenttä olettaen, että kiertoliike kulkee Weddellinpyörteen suuntaisesti kaikkialla. Virtauskentän barotrooppinen komponentti laskettiin käänteismenetelmällä, jolla pyrittiin tasapainottamaan kuljetukset mittauslinjojen läpi määritellyt ehdot täyttäen. Nämä ehdot edellyttivät suolan ja massan kuljetusten pysyvän vakioina jokaisen läpileikkauspinnan läpi. Weddellinpyörteen tilavuuden kokonaiskuljetuksen laskettiin olevan noin 19 Sverdrupia (1 Sv = 10^6 m^3/s), mikä on noin 60% kirjallisuudessa arvioiduista kuljetuksista. Weddellinmeren pohjaveden (WSBW) muodostuminen laskettiin olevan tilavuudeltaan 1,4 Sv. Tutkimuksen oleellisin tulos liittyi vesipatsaasta ilmakehään luovutetun lämmön määrään mittausalueen sisällä. Laskettu lämmönluovutus oli 12 TW (Terawattia). SWEDARP 88/89-tutkimusretken mittauksiin sisältyy ainutlaatuisia luotauksia mannerjalustalla sijaitsevassa Filchner-syvennyksessä. Nämä havainnot ansaitsisivat lisätutkimusta, samalla edistäen globaalin syvänvedenkierron tutkimuksia.The Weddell Sea on the Antarctic coast is one of the most important areas of deep-water formation in the oceans. The processes that result in deep-water formation depend on the sea area's oceanic transport mechanisms and on the climatological conditions. The primary purpose of this master’s thesis is to calculate the prevailing current conditions and to estimate changes in the water-mass properties in the Weddell Sea. This was performed by using hydrographic data collected during the SWEDARP 88/89 expedition. The first part of the thesis includes a literature study on the oceanographic conditions in the Weddell Sea. The study describes the conditions that regulate the Weddell Sea's circulation field and characteristic oceanographic processes. Transport calculations were performed by applying geostrophic methodology to data from the station network in the southwestern Weddell Sea. First, the baroclinic flow field was determined with the assumption that the cyclonic circulation of the Weddell Sea flows in a clockwise direction through each transect of the gyre. The barotropic component of the current field was then calculated using an inverse method which balances the transports through the measurement transects by meeting given criteria. These were that the transport of salt and mass is equal through each measurement transect. The total volume transport in the Weddell gyre was calculated to be about 19 Sverdrup (1 Sv = 10^6 m^3/s), which is about 60% of the transport estimated in the literature. The formation of Weddell Sea Bottom Water (WSBW) was estimated to 1.4 Sv. The primary result of the study was the amount of heat released from the water column to the atmosphere within the measurement area. The heat loss was calculated to 12 TW (terawatt). The unique SWEDARP 88/89 stations measured in the Filchner depression on the continental shelf would deserve further analysis and would enrich the studies of the global deep-water circulation.Weddellhavet vid den antarktiska kusten är ett av de viktigaste områdena där produktion av världshavens djupvatten förekommer. De processer som resulterar i djupvattenbildning är beroende av havsområdets vattentransportmekanismer och av de klimatologiska förhållandena. Avhandlingens syfte är i första hand att utföra beräkningar av de rådande strömförhållandena och uppskatta förändringar i vattenmassegenskaperna i Weddellhavet. För detta ändamål användes hydrografiska data samlade under SWEDARP 88/89-expeditionen. Den första delen av avhandlingen omfattar en litteraturstudie om de oceanografiska förhållandena i Weddellhavet. Studien redogör för de förhållanden som reglerar Weddellhavets cirkulationsfält och de oceanografiska processer som är kännetecknande för området. Transportberäkningar utfördes med att applicera geostrofisk metodik på data från stationsnätverket i sydvästra Weddellhavet. Först bestämdes det baroklina strömningsfältet med antagandet att Weddellhavets cykloniska cirkulation går i samma riktning överallt. Strömfältets barotropa komponent beräknades med hjälp av en inversteknik vars mål var att balansera transporterna igenom mätningssektionerna med att uppfylla givna kriterier. Dessa var att transporten av salt och massa är lika stor igenom varje sektion. Den totala volymtransporten i Weddellvirveln beräknades till ca 19 Sverdrup (1 Sv = 10^6 m^3/s), vilket är omkring 60 % av den transport som har uppskattats i litteraturen. Bildningen av Weddellhavets bottenvatten (WSBW) beräknades till 1,4 Sv. Det primära resultatet med studien var den mängd värme som vattenkolumnen avger till atmosfären inom mätningsområdet. Värmeförlusten beräknades till 12 TW (Terawatt). De unika SWEDARP 88/89-stationer som mättes i Filchnersänkan på kontinentalsockeln, skulle vara förtjänta fortsatt nalys, vilket skulle berika studierna av den globala djupvattencirkulationen

Retrieving Layer-Averaged Tropospheric Humidity from Advanced Technology Microwave Sounder Water Vapor Channels

A method is presented to calculate layer-averaged tropospheric humidity (LAH) from the observations of the Advanced Technology Microwave Sounder (ATMS) water vapor channels. The method is based on a linear relation between the satellite brightness temperatures (Tb) and natural logarithm of Jacobian weighted humidity. The empirical coefficients of this linear relation were calculated using different data sets, as well as a fast and a line-by-line radiative transfer (RT) model. It was found that the coefficients do not significantly depend on the data set or the RT model. This Tb to the LAH transformation method can be applied to either original or limb-corrected ATMS Tb's. The method was validated using both simulated and observed ATMS Tb's. The systematic difference between the estimated and calculated LAH values was less than 10% in most cases. We also tested the transformation method using a fixed Jacobian for each channel. The bias generally increases when fixed Jacobians are used, but there is still a satisfactory agreement between estimated and calculated LAH values. In addition, the spatial distribution of the bias was investigated using the European Center for Medium-Range Weather Forecasting (ECMWF) Interim Reanalysis (ERA-interim) and collocated ATMS observations. The bias did not indicate any significant regional dependence when actual Jacobians were used, but in the case of fixed Jacobians, the bias generally increased from middle latitude toward the poles

TanDEM-X multiparametric data features in sea ice classification over the Baltic sea

In this study, we assess the potential of X-band Interferometric Synthetic Aperture Radar imagery for automated classification of sea ice over the Baltic Sea. A bistatic SAR scene acquired by the TanDEM-X mission over the Bothnian Bay in March of 2012 was used in the analysis. Backscatter intensity, interferometric coherence magnitude, and interferometric phase have been used as informative features in several classification experiments. Various combinations of classification features were evaluated using Maximum likelihood (ML), Random Forests (RF) and Support Vector Machine (SVM) classifiers to achieve the best possible discrimination between open water and several sea ice types (undeformed ice, ridged ice, moderately deformed ice, brash ice, thick level ice, and new ice). Adding interferometric phase and coherence-magnitude to backscatter-intensity resulted in improved overall classification performance compared to using only backscatter-intensity. The RF algorithm appeared to be slightly superior to SVM and ML due to higher overall accuracies, however, at the expense of somewhat longer processing time. The best overall accuracy (OA) for three methodologies were achieved using combination of all tested features were 71.56, 72.93, and 72.91% for ML, RF and SVM classifiers, respectively. Compared to OAs of 62.28, 66.51, and 63.05% using only backscatter intensity, this indicates strong benefit of SAR interferometry in discriminating different types of sea ice. In contrast to several earlier studies, we were particularly able to successfully discriminate open water and new ice classes.Peer reviewe

Parent-of-origin-specific allelic associations among 106 genomic loci for age at menarche.

Age at menarche is a marker of timing of puberty in females. It varies widely between individuals, is a heritable trait and is associated with risks for obesity, type 2 diabetes, cardiovascular disease, breast cancer and all-cause mortality. Studies of rare human disorders of puberty and animal models point to a complex hypothalamic-pituitary-hormonal regulation, but the mechanisms that determine pubertal timing and underlie its links to disease risk remain unclear. Here, using genome-wide and custom-genotyping arrays in up to 182,416 women of European descent from 57 studies, we found robust evidence (P < 5 × 10(-8)) for 123 signals at 106 genomic loci associated with age at menarche. Many loci were associated with other pubertal traits in both sexes, and there was substantial overlap with genes implicated in body mass index and various diseases, including rare disorders of puberty. Menarche signals were enriched in imprinted regions, with three loci (DLK1-WDR25, MKRN3-MAGEL2 and KCNK9) demonstrating parent-of-origin-specific associations concordant with known parental expression patterns. Pathway analyses implicated nuclear hormone receptors, particularly retinoic acid and γ-aminobutyric acid-B2 receptor signalling, among novel mechanisms that regulate pubertal timing in humans. Our findings suggest a genetic architecture involving at least hundreds of common variants in the coordinated timing of the pubertal transition

Aging syndrome genes and premature coronary artery disease

BACKGROUND: Vascular disease is a feature of aging, and coronary vascular events are a major source of morbidity and mortality in rare premature aging syndromes. One such syndrome is caused by mutations in the lamin A/C (LMNA) gene, which also has been implicated in familial insulin resistance. A second gene related to premature aging in man and in murine models is the KLOTHO gene, a hypomorphic variant of which (KL-VS) is significantly more common in the first-degree relatives of patients with premature coronary artery disease (CAD). We evaluated whether common variants at the LMNA or KLOTHO genes are associated with rigorously defined premature CAD. METHODS: We identified 295 patients presenting with premature acute coronary syndromes confirmed by angiography. A control group of 145 patients with no evidence of CAD was recruited from outpatient referral clinics. Comprehensive haplotyping of the entire LMNA gene, including the promoter and untranslated regions, was performed using a combination of TaqMan(® )probes and direct sequencing of 14 haplotype-tagging single nucleotide polymorphisms (SNPs). The KL-VS variant of the KLOTHO gene was typed using restriction digest of a PCR amplicon. RESULTS: Two SNPs that were not in Hardy Weinberg equilibrium were excluded from analysis. We observed no significant differences in allele, genotype or haplotype frequencies at the LMNA or KLOTHO loci between the two groups. In addition, there was no evidence of excess homozygosity at the LMNA locus. CONCLUSION: Our data do not support the hypothesis that premature CAD is associated with common variants in the progeroid syndrome genes LMNA and KLOTHO

Identification of Biofilm-Associated Cluster (bac) in Pseudomonas aeruginosa Involved in Biofilm Formation and Virulence

Biofilms are prevalent in diseases caused by Pseudomonas aeruginosa, an opportunistic and nosocomial pathogen. By a proteomic approach, we previously identified a hypothetical protein of P. aeruginosa (coded by the gene pA3731) that was accumulated by biofilm cells. We report here that a ΔpA3731 mutant is highly biofilm-defective as compared with the wild-type strain. Using a mouse model of lung infection, we show that the mutation also induces a defect in bacterial growth during the acute phase of infection and an attenuation of the virulence. The pA3731 gene is found to control positively the ability to swarm and to produce extracellular rhamnolipids, and belongs to a cluster of 4 genes (pA3729–pA3732) not previously described in P. aeruginosa. Though the protein PA3731 has a predicted secondary structure similar to that of the Phage Shock Protein, some obvious differences are observed compared to already described psp systems, e.g., this unknown cluster is monocistronic and no homology is found between the other proteins constituting this locus and psp proteins. As E. coli PspA, the amount of the protein PA3731 is enlarged by an osmotic shock, however, not affected by a heat shock. We consequently named this locus bac for biofilm-associated cluster

High blood pressure in school children: prevalence and risk factors

BACKGROUND: The purpose of this study was to determine the prevalence of high blood pressure (HBP) and associated risk factors in school children 8 to 13 years of age. METHODS: Elementary school children (n = 1,066) were examined. Associations between HBP, body mass index (BMI), gender, ethnicity, and acanthosis nigricans (AN) were investigated using a school based cross-sectional study. Blood pressure was measured and the 95(th )percentile was used to determine HBP. Comparisons between children with and without HBP were utilized. The crude and multiple logistic regression adjusted odds ratios were used as measures of association. RESULTS: Females, Hispanics, overweight children, and children with AN had an increased likelihood of HBP. Overweight children (BMI ≥ 85(th )percentile) and those with AN were at least twice as likely to present with HBP after controlling for confounding factors. CONCLUSION: Twenty one percent of school children had HBP, especially the prevalence was higher among the overweight and Hispanic group. The association identified here can be used as independent markers for increased likelihood of HBP in children

Project #37: Management Guidelines for Patients with COVID-19: Rapid Cycle Improvement

Project’s purpose is to rapidly devise, continually improve, educate, and implement a live and changing COVID-19 management guideline based upon emerging best available evidence. This project also aims to optimize the care of patients with COVID-19 and improve patient outcomes.https://scholarlycommons.henryford.com/qualityexpo2022/1004/thumbnail.jp

Herbivore-Mediated Effects of Glucosinolates on Different Natural Enemies of a Specialist Aphid

The cabbage aphid Brevicoryne brassicae is a specialist herbivore that sequesters glucosinolates from its host plant as a defense against its predators. It is unknown to what extent parasitoids are affected by this sequestration. We investigated herbivore-mediated effects of glucosinolates on the parasitoid wasp Diaeretiella rapae and the predator Episyrphus balteatus. We reared B. brassicae on three ecotypes of Arabidopsis thaliana that differ in glucosinolate content and on one genetically transformed line with modified concentrations of aliphatic glucosinolates. We tested aphid performance and the performance and behavior of both natural enemies. We correlated this with phloem and aphid glucosinolate concentrations and emission of volatiles. Brevicoryne brassicae performance correlated positively with concentrations of both aliphatic and indole glucosinolates in the phloem. Aphids selectively sequestered glucosinolates. Glucosinolate concentration in B. brassicae correlated negatively with performance of the predator, but positively with performance of the parasitoid, possibly because the aphids with the highest glucosinolate concentrations had a higher body weight. Both natural enemies showed a positive performance-preference correlation. The predator preferred the ecotype with the lowest emission of volatile glucosinolate breakdown products in each test combination, whereas the parasitoid wasp preferred the A. thaliana ecotype with the highest emission of these volatiles. The study shows that there are differential herbivore-mediated effects of glucosinolates on a predator and a parasitoid of a specialist aphid that selectively sequesters glucosinolates from its host plant