Advanced Formation Fluid Evaluation While Drilling with a New Heavy Gas Detector

In this paper, a chromatograph which exploits the benefits of FID technology optimized for the high resolution detection of heavier hydrocarbon gas components is described. The components analyzed span from n-hexane to toluene. Flame Ionization Detector (FID) technology is not new to gas detection on the field, however it had never been applied to the detection of gases heavier than n-pentane. The instrumentation has been installed and run on a number of wells in different fields and countries, and it has operated as a complement of an advanced surface logging system for a period of two years. Unlike other technologies presently utilized for this scope, this system reduces dedicated equipment and personnel to a minimum. The results presented show the clear identification of formation fluid contacts with higher accuracy than standard light gas detectors, the recognition of contaminants within the drilling fluid, and the practicality of operating an advanced gas detection system with minimal operational and logistic footprint. Some of the indications obtained challenge common beliefs about gas detection: consistent extraction of heavy hydrocarbon gases from the drilling fluid is possible at relatively low temperatures, provided that the entire gas extraction system is rigorously controlled in terms of gas sample pressure, flow, and temperature. Furthermore, gas data analysis can yield indications on the fluid composition even when the gases analyzed are in extremely low quantity. The system utilizes known technologies, developed and optimized to obtain new results. The system supports formation evaluation when LWD or wireline can be inconclusive, in the presence of a low porosity pay or fresh water. It can also guide and optimize the MDT testing program. Furthermore, the system takes into account the constraints of drilling operations, and strikes a balance between data accuracy and practicality of the application

ESSAYS ON MONETARY POLICY AND CYCLICAL CONVERGENCE IN THE EURO AREA

This work contributes to the literature about the Euro-area monetary policy analysing the effects of unconventional measures, the conduct of monetary policy by the European central bank and the effects of the crisis on the economic structures of member countries. The first chapter deals with the effects of unconventional monetary policy measures implemented since 2007 to cope with the financial and sovereign debt crisis. The focus is on government bond yields as they as they became the direct expression of the sovereign debt crisis in the Euro area, and it deals with two aspects of the transmission mechanism: the first one is the expectational channel and the second one is the effect of liquidity injections. Results show that the effect of unconventional monetary policies are not unique inside the monetary union but vary across countries and over time. In particular, the unfolding of the European sovereign debt crisis completely changed the impact of liquidity injections as they led to a rise in interest rate spreads for highly indebted countries. The second chapter analyzes the conduct of monetary policy in the Euro area over the period 1999-2013 by estimating several monetary policy reaction functions with time-varying coefficients and heteroskedastic error terms. This allows to evaluate whether relevant shifts in the conduct of monetary policy occurred and whether the current financial crisis had an influence on that. Results show that the sensitivity of the ECB towards inflation and output gap changed along the time span and mainly after 2008 as it also started to respond to new variables like bank loans and sovereign bond yield spreads. The third chapter analyzes the effects of the recent economic crisis in the Euro area in light of international structural macroeconomic relationships. This is achieved through a conditional forecast exercise. By comparing the forecast with the actual path of the Euro-area variables it is possible to evaluate whether, given the effects of the crisis in US, pre-crisis structural macroeconomic relationship are able to explain Euro-area economic developments during the crisis. Results show that the effects of the crisis have been much more heterogeneous than what implied by structural relationships and the crisis shock suggesting that either a structural break or a strong idiosyncratic shock affected the Euro area after 2008. Finally, the sovereign debt crisis by itself seems not to be able to explain neither business-cycle and inflation heterogeneity, nor the recent recession and economic slack

From morphological heterogeneity at alveolar level to the overall mechanical lung behavior: an in vivo microscopic imaging study.

In six male anesthetized, tracheotomized, and mechanically ventilated rabbits, we imaged subpleural alveoli under microscopic view (60×) through a "pleural window" obtained by stripping the endothoracic fascia and leaving the parietal pleura intact. Three different imaging scale levels were identified for the analysis on increasing stepwise local distending pressure (P ld) up to 16.5 cmH2O: alveoli, alveolar cluster, and whole image field. Alveolar profiles were manually traced, clusters of alveoli of similar size were identified through a contiguity-constrained hierarchical agglomerative clustering analysis and alveolar surface density (ASD) was estimated as the percentage of air on the whole image field. Alveolar area distributions were remarkably right-skewed and showed an increase in median value with a large topology-independent heterogeneity on increasing P ld. Modeling of alveolar area distributions on increasing P ld led to hypothesize that absolute alveolar compliance (change in surface area over change in P ld) increases fairly linearly with increasing initial alveolar size, the corollary of this assumption being a constant specific compliance. Clusters were reciprocally interweaved due to their highly variable complex shapes. ASD was found to increase with a small coefficient of variation (CV <25\%) with increasing P ld. The CV of lung volume at each transpulmonary pressure was further decreased (about 6\%). The results of the study suggest that the considerable heterogeneity of alveolar size and of the corresponding alveolar mechanical behavior are homogenously distributed, resulting in a substantially homogenous mechanical behavior of lung units and whole organ

Evaluation of the residual stresses induced by shot peening on some sintered steels

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Fatigue behavior of foreign object damaged 7075 heat treated aluminum alloy coated with PVD WC/C

AbstractThe effect of a physically vapor deposited (PVD) WC/C coating on the fatigue behavior of as produced and foreign object damaged (FOD) solution heat treated and aged 7075 aluminum alloy was studied. Coated and uncoated samples were tested under rotating bending to determine the fatigue strengths between 104 and 106 cycles in both damaged and smooth condition. FOD was produced with single shots of small hard steel spheres impacting at 100 m/s in the minimum cross section. SEM was used to characterize the features of the fracture surfaces

If the Fed sneezes, who catches a cold?

This paper studies the international spillovers of US monetary policy shocks on a number of macroeconomic and financial variables in 36 advanced and emerging economies. In most countries, a surprise US monetary tightening leads to depreciation against the dollar; industrial production and real GDP fall, unemployment rises. Inflation declines especially in advanced economies. At the same time, there is significant heterogeneity across countries in the response of asset prices, and portfolio and banking cross-border flows. However, no clear-cut systematic relation emerges between country responses and likely relevant country characteristics, such as their income level, dollar exchange rate flexibility, financial openness, trade openness vs. the US, dollar exposure in foreign assets and liabilities, and incidence of commodity exports. 2017 Elsevier B.V. All rights reserved

Artificial neural-network technique for precipitation nowcasting from satellite imagery

The term nowcasting reflects the need of timely and accurate predictions of risky situations related to the development of severe meteorological events. In this work the objective is the very short term prediction of the rainfall field from geostationary satellite imagery entirely based on neural network approach. The very short-time prediction (or nowcasting) process consists of two steps: first, the infrared radiance field measured from geostationary satellite (Meteosat 7) is projected ahead in time (30 min or 1 h); secondly, the projected radiances are used to estimate the rainfall field by means of a calibrated microwave-based combined algorithm. The methodology is discussed and its accuracy is quantified by means of error indicators. An application to a satellite observation of a rainfall event over Central Italy is finally shown and evaluated

Whole-exome sequencing in a consanguineous Pakistani family identifies a mutational hotspot in the COL7A1 gene, causing recessive dystrophic epidermolysis bullosa

Dystrophic epidermolysis bullosa is a major form of epidermolysis bullosa and may be inherited as an autosomal dominant or recessive trait, with associated mutations in the COL7A1 gene. Here, we describe a consanguineous Pakistani family with four affected individuals suffering from recessive dystrophic epidermolysis bullosa. Exome sequencing of the proband's DNA revealed a homozygous missense variant (c.8038G>A:p.Gly2680Ser) in COL7A1 which cosegregated with disease in the family. The emergence of this particular glycine substitution in patients from diverse ethnic backgrounds such as China, United Kingdom, Poland, Iran, and Pakistan indicates that this variant most likely constitutes a recurrent mutational hotspot in the COL7A1 gene, rather than a germline mutation present at low levels in the general population

Transcriptional regulation of PRPF31 gene expression by MSR1 repeat elements causes incomplete penetrance in retinitis pigmentosa.

PRPF31-associated retinitis pigmentosa presents a fascinating enigma: some mutation carriers are blind, while others are asymptomatic. We identify the major molecular cause of this incomplete penetrance through three cardinal features: (1) there is population variation in the number (3 or 4) of a minisatellite repeat element (MSR1) adjacent to the PRPF31 core promoter; (2) in vitro, 3-copies of the MSR1 element can repress gene transcription by 50 to 115-fold; (3) the higher-expressing 4-copy allele is not observed among symptomatic PRPF31 mutation carriers and correlates with the rate of asymptomatic carriers in different populations. Thus, a linked transcriptional modifier decreases PRPF31 gene expression that leads to haploinsufficiency. This result, taken with other identified risk alleles, allows precise genetic counseling for the first time. We also demonstrate that across the human genome, the presence of MSR1 repeats in the promoters or first introns of genes is associated with greater population variability in gene expression indicating that copy number variation of MSR1s is a generic controller of gene expression and promises to provide new insights into our understanding of gene expression regulation

Transcriptional regulation of PRPF31 gene expression by MSR1 repeat elements causes incomplete penetrance in retinitis pigmentosa.

PRPF31-associated retinitis pigmentosa presents a fascinating enigma: some mutation carriers are blind, while others are asymptomatic. We identify the major molecular cause of this incomplete penetrance through three cardinal features: (1) there is population variation in the number (3 or 4) of a minisatellite repeat element (MSR1) adjacent to the PRPF31 core promoter; (2) in vitro, 3-copies of the MSR1 element can repress gene transcription by 50 to 115-fold; (3) the higher-expressing 4-copy allele is not observed among symptomatic PRPF31 mutation carriers and correlates with the rate of asymptomatic carriers in different populations. Thus, a linked transcriptional modifier decreases PRPF31 gene expression that leads to haploinsufficiency. This result, taken with other identified risk alleles, allows precise genetic counseling for the first time. We also demonstrate that across the human genome, the presence of MSR1 repeats in the promoters or first introns of genes is associated with greater population variability in gene expression indicating that copy number variation of MSR1s is a generic controller of gene expression and promises to provide new insights into our understanding of gene expression regulation