87 research outputs found

    The Effect of Flow at Maud Rise on the Sea Ice Cover - Numerical Experiments

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    The role of seamounts in the formation and evolution of sea ice isinvestigated in a series of numerical experiments with a coupled seaice-ocean model. Bottom topography, stratification and forcing areconfigured for the Maud Rise region in the Weddell Sea. The specificflow regime that develops at the seamount as the combined response tosteady and tidal forcing consists of free and trapped waves and aTaylor column, which is caused by mean flow and tidal flowrectification. The enhanced variability through tidal motion inparticular is capable of modifying the mixed layer above the seamountenough to delay and reduce sea ice formation throughout the winter.The induced sea ice anomaly spreads and moves westward and affects anarea of several 100~000 km2^{2}. Process studies reveal the complexinteraction between wind, steady and periodic ocean currents: allthree are required in the process of generation of the sea ice andmixed layer anomalies (mainly through tidal flow), their detachmentfrom the topography (caused by steady oceanic flow), and the westwardtranslation of the sea ice anomaly (driven by the time-mean wind)

    Taal- en kultuurbeperkings in K-12 nie-openbare skole in die Verenigde State : 'n verkenning van die reikwydte van federale nie-diskriminasie wetgewing en implikasies vir Suid-Afrika

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    In hierdie artikel ondersoek en vergelyk ons aspekte van die beperking sowel as die beskerming van taal- en kultuurregte in skoolverband (onafhanklike skole in die Verenigde State en openbare skole in Suid-Afrika). Ons doen dit deur grondwetlike en ander bepalings te bespreek en geselekteerde regspraak in die twee lande onder die vergrootglas te plaas. Ons ondersoek ook die samehang of gebrek aan samehang tussen die konsepte taal en kultuur in wetgewing en in regspraak. Ten slotte dui ons enkele besluitnemings- en bestuursimplikasies vir rolspelers in die onderwys aan en oorweeg ons ook die rol wat wetgewing en regspraak sou kon speel in die voortbestaan of ondergang van minderheidstale en -kulture.http://www.dejure.up.ac.za/am2014gv201

    Morbidity and Oncological Outcome After Curative Treatment in Sinonasal Squamous Cell Carcinoma.

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    OBJECTIVES Sinonasal squamous cell carcinomas are rare and aggressive tumors. Curative therapy includes surgery and radiotherapy, with high risk for local morbidity and impaired quality of life. The objective of this study was to analyze a large cohort of patients with sinonasal squamous cell carcinoma on treatment morbidity and oncological outcome. METHODS Patients with sinonasal squamous cell carcinoma (n = 75) treated at a tertiary referral center between 2008 and 2019 were identified. In patients with curative treatment intent (n = 70), a chart review and analysis on patient and tumor characteristics, morbidity, and oncological outcome was performed. RESULTS Mean follow-up was 59 months. Primary curative therapy was surgery alone (n = 18), surgery with radiation (n = 25), and primary (chemo)radiation (n = 27). Forty-two (60%) patients suffered from treatment-related morbidity; most frequent symptoms were dry nasal mucosa (20%), nasal obstruction (14.3%), and vision impairment or loss (11.5%). Patients with early disease had less morbidity (51.4 vs 71.1%; P = 0.09), a lower recurrence rate (27% vs. 48.5%; P = 0.08), and better overall survival (92.5% vs. 71.1%; P = 0.01). CONCLUSION Treatment-related morbidity is common after curative treatment of sinonasal squamous cell carcinomas. Early disease is beneficial in terms of occurrence and severity as multimodal treatment and recurrence can more likely be avoided

    Tailoring supercurrent confinement in graphene bilayer weak links

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    The Josephson effect is one of the most studied macroscopic quantum phenomena in condensed matter physics and has been an essential part of the quantum technologies development over the last decades. It is already used in many applications such as magnetometry, metrology, quantum computing, detectors or electronic refrigeration. However, developing devices in which the induced superconductivity can be monitored, both spatially and in its magnitude, remains a serious challenge. In this work, we have used local gates to control confinement, amplitude and density profile of the supercurrent induced in one-dimensional nanoscale constrictions, defined in bilayer graphene-hexagonal boron nitride van der Waals heterostructures. The combination of resistance gate maps, out-of-equilibrium transport, magnetic interferometry measurements, analytical and numerical modelling enables us to explore highly tunable superconducting weak links. Our study opens the path way to design more complex superconducting circuits based on this principle such as electronic interferometers or transition-edge sensors

    Surface Modification of Luminescent Lanthanide Phosphate Nanorods with Cationic "Quat-primer" Polymers

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    Komban R, Beckmann R, Rode S, et al. Surface Modification of Luminescent Lanthanide Phosphate Nanorods with Cationic "Quat-primer" Polymers. Langmuir. 2011;27(16):10174-10183."Quat-primer" polymers bearing cationic groups were investigated as a surface modifier for Tb-doped cerium phosphate green-emitting fluorescent nanorods (NRs). The NRs were synthesized by a microwave process without using any complex agents or ligands and were characterized with different analytical tools such as X-ray diffraction, transmission electron microscopy, and fluorescence spectroscopy. Poly(ethyleneimine) partially quarternized with glycidyltrimethylammonium chloride was synthesized separately and characterized in detail. (1)H and (13)C NMR spectroscopic studies revealed that the quaternary ammonium group was covalently attached to the polymer. UV-vis spectroscopy was used to examine the stability of the colloidal dispersions of the bare NRs as well as the modified NRs zeta potential, thermogravimetric analysis, and atomic force microscopy studies were carried out to confirm that the positively charged Quat-primer polymer is adsorbed on the negatively charged surface of the NRs, which results in high dispersion stability. Emission spectra of the modified NRs indicated that there was no interference of the Quat-primer polymer with the fluorescence behavior

    Reliability of prenatal detection of X-linked hypohidrotic ectodermal dysplasia by tooth germ sonography

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    Objective In X‐linked hypohidrotic ectodermal dysplasia (XLHED), dysfunction of ectodysplasin A1 (EDA1) due to EDA mutations results in malformation of hair, teeth, and sweat glands. Hypohidrosis, which can cause life‐threatening hyperthermia, is amenable to intrauterine therapy with recombinant EDA1. This study aimed at evaluating tooth germ sonography as a noninvasive means to identify affected fetuses in pregnant carrier women. Methods Sonography, performed at 10 study sites between gestational weeks 18 and 28, led to the diagnosis of XLHED if fewer than six tooth germs were detected in mandible or maxilla. The assessment was verified postnatally by EDA sequencing and/or clinical findings. Estimated fetal weights and postnatal weight gain of boys with XLHED were assessed using appropriate growth charts. Results In 19 of 38 sonographic examinations (23 male and 13 female fetuses), XLHED was detected prenatally. The prenatal diagnosis proved to be correct in 37 cases; one affected male fetus was missed. Specificity and positive predictive value were both 100%. Tooth counts obtained by clinical examination corresponded well with findings on panoramic radiographs. We observed no weight deficits of subjects with XLHED in utero but occasionally during infancy. Conclusion Tooth germ sonography is highly specific and reliable in detecting XLHED prenatally

    Tailoring supercurrent confinement in graphene bilayer weak links

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    The Josephson effect is one of the most studied macroscopic quantum phenomena in condensed matter physics and has been an essential part of the quantum technologies development over the last decades. It is already used in many applications such as magnetometry, metrology, quantum computing, detectors or electronic refrigeration. However, developing devices in which the induced superconductivity can be monitored, both spatially and in its magnitude, remains a serious challenge. In this work, we have used local gates to control confinement, amplitude and density profile of the supercurrent induced in one-dimensional nanoscale constrictions, defined in bilayer graphene-hexagonal boron nitride van der Waals heterostructures. The combination of resistance gate maps, out-of-equilibrium transport, magnetic interferometry measurements, analytical and numerical modelling enables us to explore highly tunable superconducting weak links. Our study opens the path way to design more complex superconducting circuits based on this principle, such as electronic interferometers or transition-edge sensors

    New genetic loci link adipose and insulin biology to body fat distribution.

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    Body fat distribution is a heritable trait and a well-established predictor of adverse metabolic outcomes, independent of overall adiposity. To increase our understanding of the genetic basis of body fat distribution and its molecular links to cardiometabolic traits, here we conduct genome-wide association meta-analyses of traits related to waist and hip circumferences in up to 224,459 individuals. We identify 49 loci (33 new) associated with waist-to-hip ratio adjusted for body mass index (BMI), and an additional 19 loci newly associated with related waist and hip circumference measures (P < 5 × 10(-8)). In total, 20 of the 49 waist-to-hip ratio adjusted for BMI loci show significant sexual dimorphism, 19 of which display a stronger effect in women. The identified loci were enriched for genes expressed in adipose tissue and for putative regulatory elements in adipocytes. Pathway analyses implicated adipogenesis, angiogenesis, transcriptional regulation and insulin resistance as processes affecting fat distribution, providing insight into potential pathophysiological mechanisms

    Causal effect of plasminogen activator inhibitor type 1 on coronary heart disease

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    Background--Plasminogen activator inhibitor type 1 (PAI-1) plays an essential role in the fibrinolysis system and thrombosis. Population studies have reported that blood PAI-1 levels are associated with increased risk of coronary heart disease (CHD). However, it is unclear whether the association reflects a causal influence of PAI-1 on CHD risk. Methods and Results--To evaluate the association between PAI-1 and CHD, we applied a 3-step strategy. First, we investigated the observational association between PAI-1 and CHD incidence using a systematic review based on a literature search for PAI-1 and CHD studies. Second, we explored the causal association between PAI-1 and CHD using a Mendelian randomization approach using summary statistics from large genome-wide association studies. Finally, we explored the causal effect of PAI-1 on cardiovascular risk factors including metabolic and subclinical atherosclerosis measures. In the systematic meta-analysis, the highest quantile of blood PAI-1 level was associated with higher CHD risk comparing with the lowest quantile (odds ratio=2.17; 95% CI: 1.53, 3.07) in an age- and sex-adjusted model. The effect size was reduced in studies using a multivariable-adjusted model (odds ratio=1.46; 95% CI: 1.13, 1.88). The Mendelian randomization analyses suggested a causal effect of increased PAI-1 level on CHD risk (odds ratio=1.22 per unit increase of log-transformed PAI-1; 95% CI: 1.01, 1.47). In addition, we also detected a causal effect of PAI-1 on elevating blood glucose and high-density lipoprotein cholesterol. Conclusions--Our study indicates a causal effect of elevated PAI-1 level on CHD risk, which may be mediated by glucose dysfunction

    Beyond Structural Genomics for Plant Science

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