On Random Sampling and Fourier Transform Estimation in Sea Waves Prediction

Improving the safety of a wide range of launch and recovery operations is of great international maritime interest. Deterministic sea wave prediction (DSWP) is a relatively new branch of science that can offer such opportunities by predicting the actual shape of the sea surface and its evolution for short time in the future. Fourier transform technique is the main building block in DSWP, which requires measurements of the sea surface. Nonetheless, uniformly sampled measurements of the sea surface cannot be practically achieved for various reasons. Conventional X-band radars are the most realistic candidate to provide a low-cost convenient source of two-dimensional wave profile information for DSWP purposes. Ship movement and mechanically rotating scanning antennas are among sources of irregularity in sea surface sampling. This in turn introduces errors when traditional Fourier transform based wave prediction methods are used. In this paper we show that by modelling the radar sampling instants as random variables and using the estimator of Tarczynski and Allay to process the samples, a reliable solution for DSWP can be constituted

Adjusted Location Privacy Scheme in VANET Safety Applications

The primary aim of Vehicular Ad hoc NETworks (VANET) is to enhance traffic safety by enabling frequent broadcasting of location information between vehicles. In VANET safety applications, a vehicle requires to broadcast messages, which usually contain its location information, every (1-10 Hz) with other vehicles in its communication area (300m) to facilitate cooperative awareness. This would arise privacy issues because vehicles are vulnerable to tracking attacks via their locations. To prevent long-term linking, many privacy schemes have adopted a silent period in which a vehicle stops sharing its locations for a period. However, silent periods could have a negative impact on safety applications as an accident could have happened if a vehicle stop sharing its locations with other neighbours. Thus, in this paper, we first discuss three privacy schemes (RSP, SLOW and CAPS), which adopted silent periods but in different concepts. Then, we improve the privacy and safety level of CAPS. A privacy simulator PREXT is used to evaluate and compare the performance of schemes

El efecto de la temperatura en la caracterización de clicker de cemento con una sustitución del 10% de la piedra de basalto en la masa de piedra caliza

This research was conducted to determine the effect of temperature on the chemical content and crystal structure of the cement clinker with 10% substitution of basalt on the mass of limestone. The cement clinker is made from the composition of limestone, basalt stone, clay, silica stone and iron sand. Basalt stone used came from the East Lampung area. The basalt stone has fulfilled ASTM C618 standard with a total compound of SiO2 + Al2O3 + Fe2O3 of 79.2%. The raw material was then mixed, milled, formed into pellets with a size of 0.8 - 1.4 cm and continued with combustion at calcination temperatures of 1000 ℃, 1100 ℃ and 1200 with a holding time of 2 hours. Based on the results of the XRF test (X-Ray Fluorecence) of the three cement clinker samples with variations in temperature used, the sample is closer to the standard at a temperature of 1000 ℃. For the XRD (X-Ray Diffraction) test results, the three samples have tetragonal, monoclinic, rhombohedral, and orthorhombic crystal structures. As for the MO test results, there was a strong binding between iron sand, limestone, clay, and silica sand characterized by a smooth surface while basalt stones that look like black holes were not completely bound.Esta investigación se realizó para determinar el efecto de la temperatura sobre el contenido químico y la estructura cristalina del clínker de cemento con un 10% de sustitución de basalto sobre la masa de piedra caliza. El clínker de cemento está hecho de la composición de piedra caliza, piedra de basalto, arcilla, piedra de sílice y arena de hierro. La piedra de basalto utilizada vino del área de East Lampung. La piedra de basalto ha cumplido el estándar ASTM C618 con un compuesto total de SiO2 + Al2O3 + Fe2O3 del 79,2%. La materia prima se mezcló, se molió, se formó en gránulos con un tamaño de 0,8 a 1,4 cm y se continuó con la combustión a temperaturas de calcinación de 1000 ℃, 1100 ℃ y 1200 con un tiempo de retención de 2 horas. Según los resultados de la prueba XRF (fluorescencia de rayos X) de las tres muestras de clínker de cemento con variaciones de temperatura utilizadas, la muestra está más cerca del estándar a una temperatura de 1000 ℃. Para los resultados de la prueba de XRD (difracción de rayos X), las tres muestras tienen estructuras cristalinas tetragonales, monoclínicas, romboédricas y ortorrómbicas. En cuanto a los resultados de la prueba de MO, hubo una fuerte unión entre arena de hierro, piedra caliza, arcilla y arena de sílice caracterizada por una superficie lisa, mientras que las piedras de basalto que parecen agujeros negros no estaban completamente unidas

Changes in urinary metabolomic profile during relapsing renal vasculitis

Current biomarkers of renal disease in systemic vasculitis lack predictive value and are insensitive to early damage. To identify novel biomarkers of renal vasculitis flare, we analysed the longitudinal urinary metabolomic profile of a rat model of anti-neutrophil cytoplasmic antibody (ANCA) vasculitis. Wistar-Kyoto (WKY) rats were immunised with human myeloperoxidase (MPO). Urine was obtained at regular intervals for 181 days, after which relapse was induced by re-challenge with MPO. Urinary metabolites were assessed in an unbiased fashion using nuclear magnetic resonance (NMR) spectroscopy, and analysed using partial least squares discriminant analysis (PLS-DA) and partial least squares regression (PLS-R). At 56 days post-immunisation, we found that rats with vasculitis had a significantly different urinary metabolite profile than control animals; the observed PLS-DA clusters dissipated between 56 and 181 days, and re-emerged with relapse. The metabolites most altered in rats with active or relapsing vasculitis were trimethylamine N-oxide (TMAO), citrate and 2-oxoglutarate. Myo-inositol was also moderately predictive. The key urine metabolites identified in rats were confirmed in a large cohort of patients using liquid chromatography-mass spectrometry (LC-MS). Hypocitraturia and elevated urinary myo-inositol remained associated with active disease, with the urine myo-inositol:citrate ratio being tightly correlated with active renal vasculitis

El efecto de la temperatura en la caracterización de clicker de cemento con una sustitución del 10% de la piedra de basalto en la masa de piedra caliza

Esta investigación se realizó para determinar el efecto de la temperatura sobre el contenido químico y la estructura cristalina del clínker de cemento con un 10% de sustitución de basalto sobre la masa de piedra caliza. El clínker de cemento está hecho de la composición de piedra caliza, piedra de basalto, arcilla, piedra de sílice y arena de hierro. La piedra de basalto utilizada vino del área de East Lampung. La piedra de basalto ha cumplido el estándar ASTM C618 con un compuesto total de SiO2 + Al2O3 + Fe2O3 del 79,2%. La materia prima se mezcló, se molió, se formó en gránulos con un tamaño de 0,8 a 1,4 cm y se continuó con la combustión a temperaturas de calcinación de 1000 ℃, 1100 ℃ y 1200 con un tiempo de retención de 2 horas. Según los resultados de la prueba XRF (fluorescencia de rayos X) de las tres muestras de clínker de cemento con variaciones de temperatura utilizadas, la muestra está más cerca del estándar a una temperatura de 1000 ℃. Para los resultados de la prueba de XRD (difracción de rayos X), las tres muestras tienen estructuras cristalinas tetragonales, monoclínicas, romboédricas y ortorrómbicas. En cuanto a los resultados de la prueba de MO, hubo una fuerte unión entre arena de hierro, piedra caliza, arcilla y arena de sílice caracterizada por una superficie lisa, mientras que las piedras de basalto que parecen agujeros negros no estaban completamente unidas

Assessment of peripartum psychological disturbances in relation to modes of delivery

Background:Anxiety disorders are common during peripartum period.This study aimed to identify which mode of delivery was more prone to develop psychological disturbances.Methods:This prospective cohort study conducted among 541 pregnant women presented for spontaneous labour, induction or elective caesarean section in a Malaysian hospital. The severity of depression, anxiety and stress symptoms are assessed by using self-rated depression anxiety and stress scales in four different occasions; pre-labour/operation, 24 hours postnatal, 2 weeks,and at 6weeks.Results:In the prenatal period, there was no statistically significant difference in the mean score of depression between women coming for labour (4.17 ±5.28) and elective CS (4.21 ±5.87). During puerperium; at 24 hours postnatal, 2weeks and 6weeks assessments there was no significant difference in depression score among patients with different modes of delivery. The overall scores were (4.23 ±5.46, 3.26 ±4.85, 0.78 ±2.37, 0.18 ±0.93) for patients going through vaginal delivery, instrumentation, emergency or elective CS. The same trend was found when anxiety and stress were analysed. Conclusions:The most prominent peripartum psychological disturbances symptom is anxiety. Minority of patients will experience persistence anxiety by the end of 6 weeks postpartum. The caesarean section and induction of labour does not increase the psychological impact

Anti-proteinase 3 anti-neutrophil cytoplasm autoantibodies recapitulate systemic vasculitis in mice with a humanized immune system.

Evidence is lacking for direct pathogenicity of human anti-proteinase-3 (PR3) antibodies in development of systemic vasculitis and granulomatosis with polyangiitis (GPA, Wegener's granulomatosis). Progress in study of these antibodies in rodents has been hampered by lack of PR3 expression on murine neutrophils, and by different Fc-receptor affinities for IgG across species. Therefore, we tested whether human anti-PR3 antibodies can induce acute vasculitis in mice with a human immune system. Chimeric mice were generated by injecting human haematopoietic stem cells into irradiated NOD-scid-IL2Rγ⁻/⁻ mice. Matched chimera mice were treated with human IgG from patients with: anti-PR3 positive renal and lung vasculitis; patients with non-vasculitic renal disease; or healthy controls. Six-days later, 39% of anti-PR3 treated mice had haematuria, compared with none of controls. There was punctate bleeding on the surface of lungs of anti-PR3 treated animals, with histological evidence of vasculitis and haemorrhage. Anti-PR3 treated mice had mild pauci-immune proliferative glomerulonephritis, with infiltration of human and mouse leukocytes. In 3 mice (17%) more severe glomerular injury was present. There were no glomerular changes in controls. Human IgG from patients with anti-PR3 autoantibodies is therefore pathogenic. This model of anti-PR3 antibody-mediated vasculitis may be useful in dissecting mechanisms of microvascular injury

Global burden of human brucellosis : a systematic review of disease frequency

BACKGROUND: This report presents a systematic review of scientific literature published between 1990-2010 relating to the frequency of human brucellosis, commissioned by WHO. The objectives were to identify high quality disease incidence data to complement existing knowledge of the global disease burden and, ultimately, to contribute towards the calculation of a Disability-Adjusted Life Years (DALY) estimate for brucellosis.METHODS/PRINCIPAL FINDINGS: Thirty three databases were searched, identifying 2,385 articles relating to human brucellosis. Based on strict screening criteria, 60 studies were selected for quality assessment, of which only 29 were of sufficient quality for data analysis. Data were only available from 15 countries in the regions of Northern Africa and Middle East, Western Europe, Central and South America, Sub-Saharan Africa, and Central Asia. Half of the studies presented incidence data, six of which were longitudinal prospective studies, and half presented seroprevalence data which were converted to incidence rates. Brucellosis incidence varied widely between, and within, countries. Although study biases cannot be ruled out, demographic, occupational, and socioeconomic factors likely play a role. Aggregated data at national or regional levels do not capture these complexities of disease dynamics and, consequently, at-risk populations or areas may be overlooked. In many brucellosis-endemic countries, health systems are weak and passively-acquired official data underestimate the true disease burden.CONCLUSIONS: High quality research is essential for an accurate assessment of disease burden, particularly in Eastern Europe, the Asia-Pacific, Central and South America and Africa where data are lacking. Providing formal epidemiological and statistical training to researchers is essential for improving study quality. An integrated approach to disease surveillance involving both human health and veterinary services would allow a better understand of disease dynamics at the animal-human interface, as well as a more cost-effective utilisation of resources