Races using kitefoil and windfoil surfboards have been in the Olympic Games for the first time in Paris 2024,signalling their relevance in sailing sports.However,the dynamics of these devices is yet not well understoo...Races using kitefoil and windfoil surfboards have been in the Olympic Games for the first time in Paris 2024,signalling their relevance in sailing sports.However,the dynamics of these devices is yet not well understood,in particular the influence on the hydrodynamic forces and moments of the distance of the foil to the free surface.Considering this,the present paper documents an experimental investigation in which forces and torque produced,under uniform flow,by a full-scale state-of-the-art hydrofoil(suitable both for kitesurf and windsurf)were measured.A range of velocities,angles of attack,and submergences were tested,leading to Froude numbers based on submergence with maximum values around five,a typical range in actual sailing conditions.From these tests,formulae for the hydrodynamic coefficients have been proposed.They can be used for developing Velocity Prediction Programs(VPP)for this kind of craft,a necessary tool to plan racing configurations and to analyze their racing performance.With the aim of making the experimental data useful for benchmarking numerical models and for future research on related topics such as foil ventilation and transition to turbulence,the specimen’s 3D file is provided as supplementary material to this paper.展开更多
Based on the tree-ring growth characteristics of Erman＇s birch （Betula ermanii charm.） and the relationships between it and climatic ）＇actors at elevation of 1950m, the sensitivity of tree lines in Changbai Mount...Based on the tree-ring growth characteristics of Erman＇s birch （Betula ermanii charm.） and the relationships between it and climatic ）＇actors at elevation of 1950m, the sensitivity of tree lines in Changbai Mountain to climatic factors was assessed. The results indicated tree line forest in Changbai Mountain had an obvious sensitivity to climate factors. However, difference from other study sits is that the main climatic control factor on tree-ring growth was not current growth season temperatures, as might be expected, but previous winter and current March temperature. Although the precipitation in the region was quite abundant, the tree-ring growth was still significantly correlated with the precipitation during previous winter and current spring. Additionally, climatic factors which influenced the Erman＇s birch growth were not the yearly variables, but seasonal and monthly variables. Therefore, the reported increase in yearly mean temperature and total yearly precipitation since 1980s was not responded by sustained increase in ring widths in recent decades.展开更多
The composition of ashes stemming from the burning of medical waste is similar to that of urban waste. Specific pieces of evidence are looked for that allowed distinguishing some components in those waste products. A ...The composition of ashes stemming from the burning of medical waste is similar to that of urban waste. Specific pieces of evidence are looked for that allowed distinguishing some components in those waste products. A selection is carried out and some elements are included in a glass matrix. An unexpected result is presented here. It is possible to differentiate sterile and non-sterile medical gloves. The main difference is the relative amounts of calcium, in glass forming. Glasses are manufactured with a mono-ammonium phosphate since it is a natural product in Morocco. Several compositions are tried and studied. These compositions are expressed in usual two ternary and one quaternary systems built with the four equivalent components： SiO2, A1203, P205 and CaO and then compared to a patented composition.展开更多
Greywater, a type of wastewater, may be hazardous to human health and ecosystems. Greywater is a large fraction of wastewater that needs adequate attention for remediation and reuse in the agricultural sector so that ...Greywater, a type of wastewater, may be hazardous to human health and ecosystems. Greywater is a large fraction of wastewater that needs adequate attention for remediation and reuse in the agricultural sector so that a part of the water problem can be sorted out. This study aims to develop a rapid method for greywater treatment and reuse in agriculture. A microfilter consisting of sand, clay, organo-clay, charcoal, and biochar was designed and tested for greywater treatments. Biological Oxygen Demand (BOD), Chemical Oxygen Demand (COD), Total Kjeldahl Nitrogen (TKN), Total Dissolved Salts (TDS), Electric Conductivity (EC), turbidity and pH values were measured before and after using the microfilter. Results showed tremendous removal efficiency of BOD, COD, TKN, by using the developed microfilter. The microfilter was also effective in treating and placing pH, EC and TDS in the acceptable range for suitable agricultural use. Using the treated greywater for irrigation in corn, tomato seedlings showed increased growth compared with the control group (plants irrigated with tap water). This microfilter treatment was economical, safe, easy to handle and easily applicable. These encouraging results suggest the application of this method in many countries for solving the water scarcity problem.展开更多
Depuis2001,et conform ment nos engagements aupr s de la population,la municipalit que j ai I honneur de conduire a mis en oeuvre une politique destin e 《faire revivre N⒌mes》. Cela s est d j traduit dans des domaine...Depuis2001,et conform ment nos engagements aupr s de la population,la municipalit que j ai I honneur de conduire a mis en oeuvre une politique destin e 《faire revivre N⒌mes》. Cela s est d j traduit dans des domaines tr s sensibles localement comme la s curit des biens et des personˉnes,la propret des espaces publics,la qualit et la diversit des animations-qu elles soient culturelles,festives ou sportives-,l accueil de nouvelles entreprises...展开更多
Despite recent progress in deep-sea biodiversity assessments in the Southern Ocean （SO）, there remain gaps in our knowledge that hamper efficient deep-sea monitoring in times of rapid climate change. These include g...Despite recent progress in deep-sea biodiversity assessments in the Southern Ocean （SO）, there remain gaps in our knowledge that hamper efficient deep-sea monitoring in times of rapid climate change. These include geographical sampling bias, depth and size-dependent faunal gaps in biology, ecology, distribution, and phylogeography, and the evolution of SO species. The phenomena of species patchiness and rarity are still not well understood, possibly because of our limited understanding of physiological adaptations and thresholds. Even though some shallow water species have been investigated physiologically, community-scale studies on the effects of multiple stressors related to ongoing environmental change, including temperature rise, ocean acidification, and shifts in deposition of phytoplankton, are completely unknown for deep-sea organisms. Thus, the establishment of long-term and coordinated monitoring programs, such as those rapidly growing under the umbrella of the Southern Ocean Observing System （SOOS） or the Deep Ocean Observing Strategy （DOOS）, may represent unique tools for measuring the status and trends of deep-sea and SO ecosystems.展开更多
Background/Aims: Egypt has the highest prevalence of Hepatitis C Virus (HCV) in the world, aPPArently due to mass parenteral antischistosomal therapy. Estimating the future burden of HCV in Egypt is important to suppo...Background/Aims: Egypt has the highest prevalence of Hepatitis C Virus (HCV) in the world, aPPArently due to mass parenteral antischistosomal therapy. Estimating the future burden of HCV in Egypt is important to support health policies to combat the epidemic. Methods: A previous back calculation model was adapted to the situation in Egypt. It combines a model of the natural history of HCV infections with available epidemiological data to back calculate the past HCV incidence from observed 1980- 1999 hepatocellular carcinoma (HCC) mortality. In turn, the HCV-related mortality burden is projected in the future due to pre- 2000 infections. Results: Compared with the observed number of HCC deaths in 1999, the model predicts a 3.5- fold increase in this mortality in the next 20 years. Globally, the model predicts a 2.4- fold increase in theHCV-related mortality. These predictions do not take into account the new infections that may occur after 2000, which would still increase the estimated future mortality burden. Conclusions: HCV-related mortality is expected at least to double in the next 20 years. The use of antiviral therapies can lower these predictions. Efficient prevention policies are needed to avoid these predictions being exceeded.展开更多
The Voigt function is the convolution of a Lorentzian and a Guaussian density. The computation of these functions is required in several problems arising in a variety of physicochemical subjects;such as nuclear reacto...The Voigt function is the convolution of a Lorentzian and a Guaussian density. The computation of these functions is required in several problems arising in a variety of physicochemical subjects;such as nuclear reactors, atmospheric transmittance and spectroscopy. In this work we suggest using a new formula for the calculation of the Voigt function. Our formula is a new integral representation for the Voigt function that gives the perfect results for the Voigt function calculation and is easily calculable. We give also a comparison between our results of calculation of Voigt function for the very small values of the parameter a, where the calculation is notoriously difficult, with those of the various algorithms of other authors.展开更多
Carbon nanotubes flower(CNTs-F)films were prepared by catalytic chemical vapor deposition(CVD)on a platinum(Pt)thin layer,supported on a silicon wafer.The products were synthesized from an aerosol composed of ferrocen...Carbon nanotubes flower(CNTs-F)films were prepared by catalytic chemical vapor deposition(CVD)on a platinum(Pt)thin layer,supported on a silicon wafer.The products were synthesized from an aerosol composed of ferrocene and toluene,as catalyst and carbon precursor respectively,at 820.The high synthesis temperature induces a modification of a Pt thin layer to a nano-structured island giving rise to the formation of CNTs-F during the following films growth step by CVD process.The suggested mechanism involves the selective diffusion of the catalyst and carbon atoms through the Pt grain boundaries.This results in the appearance of flower-like structures with 3-and 4-fold symmetries.展开更多
Aims: To identify factors, which were related to being smoke-free and snus-free, respectively, among adolescents in relation to adolescents who were smoking and/or using snus, and determine if there were any sex diffe...Aims: To identify factors, which were related to being smoke-free and snus-free, respectively, among adolescents in relation to adolescents who were smoking and/or using snus, and determine if there were any sex differences. Methods: A questionnaire study was performed among students in year two in upper secondary schools (17-years-old) in southern Sweden in 2009. More than 2200 students completed the questionnaire regarding health and living habits anonymously. The variables were tested by χ2-test, before selection into the logistic model. Because of the salutogenic approach in the study, the results of the logistic regression analyses were expressed as Positive Odds Ratio (POR). Results: The prevalence of being smoke- free was 75.6 percent for girls and 70.2 percent for boys, whilst the prevalence of being snus- free was 95.1 percent for girls and 70.2 percent for boys. Having a tobacco-free best friend was the most important factor that correlated with being smoke- and snus-free as an adolescent, for both boys and girls. Good living habits, such as drinking less alcohol, were also central to being smoke-free and snus-free. Conclusions: The results show that a tobacco-free environment has a great influence on whether or not adolescents stay tobacco-free. As the environment has a big impact, the school has a big challenge to work with the school environment and policies but also with family responsibility, norms and attitudes to tobacco.展开更多
The communication system known as quorum sensing (QS) in gram-negative bacteria regulates biofilm formation and many other functions. The particularity of Pseudoalteromonas ulvae TC14 seems to be the absence of a LuxI...The communication system known as quorum sensing (QS) in gram-negative bacteria regulates biofilm formation and many other functions. The particularity of Pseudoalteromonas ulvae TC14 seems to be the absence of a LuxI inducer, and therefore the lack of production of small molecules of Acyl homoserine lactone (AHL). Previous studies had shown that it does not harbor the inducer of the regulatory molecule (AHL). Nevertheless, it is able to regulate these same functions (biofilm, violacein) via AHLs. This could mean the presence of specific receptors for these induction molecules, belonging to the LuxR family. The aim of this study was to test these hypotheses using molecular analysis. Genome sequencing of the P. ulvae TC14 strain was carried out by Molecular Research LP (MR DNA), using the Illumina Hiseq 2500 method. The results revealed the presence of 2,293,242 base pairs, i.e. 100% of the genomic volume. The number of coding gene sequences was 1983, and the Guanine + Cytosine (G+C) percentage of the base number was 41.55%, revealing stability in the sequenced genome. In order to verify the identity of the sequenced genome, a phylogenetic analysis based on RNA16S was carried out. This analysis resulted in 93% homology with the previously sequenced and characterized species Pseudoalteromonas tunicata, showing that it belongs to the genus Pseudoalteromonas. To these comparative results should be added those derived from genome analysis based on nucleotide percentage using the tools available at https://img.jgi.doe.gov/. The results showed that Pseudoalteromonas tunicata D2 has the highest percentage nucleotide identity (ANI) (75.7913%), followed by Pseudoalteromonas flavipulchra NCIMB2033 (72.2736%) and Pseudoalteromonas phenolica KCTC 12086 (71.6685%). Next, the search for the various genes involved in QS was carried out using sequence comparisons via the BLAST method. For LuxI, sequence templates from the genomes of Vibrio, Chromobacterium, Shewanella or even other Pseudoalteromonas species were screened against the TC14 genome. This yielded no conclusive results synonymous with the non-presence of LuxI in TC14 as assumed by previous research. The search for LuxR, on the other hand, gave rise to the presence of eight presumptive sequences. Molecular characterization of the presumptive LuxR sequences was carried out to assess their gene expression. This characterization showed expression of these LuxR homologous sequences in a range from o.11 to 5.33 picograms (pg). Even if these sequences were not analyzed in depth, the retro-transcription technique nevertheless showed a minimum of activity, which could enable us to distinguish them from inactive sequences. The next step was to compare the LuxRs found in TC14 with the so-called Solo LuxRs, which act autonomously. This study shows that P. ulvae TC14 is a bacterium with a particular LuxR-based communication system.展开更多
In this article,we study the convergence of an IIPG(Incomplete Interior Penalty Galerkin)Discontinuous Galerkin numerical method for the Richards equation.The Richards equation is a degenerate parabolic nonlinear equa...In this article,we study the convergence of an IIPG(Incomplete Interior Penalty Galerkin)Discontinuous Galerkin numerical method for the Richards equation.The Richards equation is a degenerate parabolic nonlinear equation for modeling flows in porous media with variable saturation.The numerical solution of this equation is known to be difficult to calculate numerically,due to the abrupt displacement of the wetting front,mainly as a result of highly nonlinear hydraulic properties.As time scales are slow,implicit numerical methods are required,and the convergence of nonlinear solvers is very sensitive.We propose an original method to ensure convergence of the numerical solution to the exact Richards solution,using a technique of auto-calibration of the penalty parameters derived from the Galerkin Discontinuous method.The method is constructed using nonlinear 1D and 2D general elliptic problems.We show that the numerical solution converges toward the unique solution of the continuous problem under certain conditions on the penalty parameters.Then,we numerically demonstrate the efficiency and robustness of the method through test cases with analytical solutions,laboratory test cases,and large-scale simulations.展开更多
We propose a new section-averaged one-dimensional model for blood flows in deformable arteries.The model is derived from the three-dimensional Navier-Stokes equations,written in cylindrical coordinates,under the“thin...We propose a new section-averaged one-dimensional model for blood flows in deformable arteries.The model is derived from the three-dimensional Navier-Stokes equations,written in cylindrical coordinates,under the“thin-artery”assumption(similar to the“shallow-water”assumption for free surface models).The blood flow/artery interaction is taken into account through suitable boundary conditions.The obtained equations enter the scope of the nonlinear convection-diffusion problems.We show that the resulting model is energetically consistent.The proposed model extends most extant models by adding more scope,depending on an additional viscous term.We compare both models computationally based on an Incomplete Interior Penalty Galerkin(IIPG)method for the parabolic part,and on a Runge Kutta Discontinuous Galerkin(RKDG)method for the hyperbolic part.The time discretization explicit/implicit is based on the well-known Additive Runge-Kutta(ARK)method.Moreover,through a suitable change of variables,by construction,we show that the numerical scheme is well-balanced,i.e.,it preserves exactly still-steady state solutions.To end,we numerically investigate its efficiency through several test cases with a confrontation to an exact solution.展开更多
We propose a new two-dimensional blood flow reduced model taking into account of complex artery geometry as in the case of severe aneurysm.We derive the model from the three-dimensional Navier-Stokes equations written...We propose a new two-dimensional blood flow reduced model taking into account of complex artery geometry as in the case of severe aneurysm.We derive the model from the three-dimensional Navier-Stokes equations written in a curvilinear coordinate system under the thin-artery assumption,with boundary conditions including wall tissue deformation.We show that the model is energetically consistent with the full Navier-Stokes problem.This model,obtained via radial averaging,is,up to our knowledge,the first one.It has the advantage of being more accurate than the classical one-dimensional models and being solved in a reasonable time in comparison with the Navier-Stokes models.To this purpose,we use a Runge-Kutta Discontinuous Galerkin(RKDG)method to solve the two-dimensional problem.We end the paper with several numerical test cases to show the efficiency and robustness of the numerical model,and in particular,we show the limit of the one-dimensional models in the case of a severe aneurysm.展开更多
We investigate a version of one velocity Baer-Nunziato model with dissipation for the mixture of two compressible fluids with the goal to prove for it the existence of weak solutions for arbitrary large initial data o...We investigate a version of one velocity Baer-Nunziato model with dissipation for the mixture of two compressible fluids with the goal to prove for it the existence of weak solutions for arbitrary large initial data on a large time interval.We transform the one velocity Baer-Nunziato system to another"more academic"system which possesses the clear"Navier-Stokes structure".We solve the new system by adapting to its structure the Lions approach for solving the(mono-fluid)compressible Navier-Stokes equations.An extension of the theory of renormalized solutions to the transport equation to more continuity equations with renormalizing functions of several variables is essential in this process.We derive a criterion of almost uniqueness for the renormalized solutions to the pure transport equation without the classical assumption on the boundedness of the divergence of the transporting velocity.This result does not follow from the DiPerna-Lions transport theory and it is of independent interest.This criterion plays the crucial role in the identification of the weak solutions to the original one velocity Baer-Nunziato problem starting from the weak solutions of the academic problem.As far as we know,this is the first result on the existence of weak solutions for a version of the one velocity bi-fluid system of the Baer-Nunziato type in the mathematical literature.展开更多
Background: Cardiovascular disease (CVD) is the major noncommunicable disease (NCD) accounting for 17.9 million deaths. If current trends continue, the annual number of deaths from CVD will rise to 22.2 million by 203...Background: Cardiovascular disease (CVD) is the major noncommunicable disease (NCD) accounting for 17.9 million deaths. If current trends continue, the annual number of deaths from CVD will rise to 22.2 million by 2030. The United Nations General Assembly adopted a sustainable development goal (SDG) by 2030 to reduce NCD mortality by one-third. The purpose of this study was to analyze the CVD mortality trends in different countries implementing World Health Organization (WHO) NCD Action Plan and emphasize effective ways to achieve SDG.Methods: WHO statistics, based on the Member-States unified mortality and causes-of-death reports were used for analyzing trends and different interventions.Results: Reduction of CVD mortality from 2000 to 2016 in 49 countries was achieved for stroke at 43% and ischemic heart disease at 30%. Smoking prevalence and raised blood pressure (RBP) decreased in 84% and 55% of the countries. Eighty-nine percent of high-income countries (HIC) demonstrated a decline in tobacco smoking against 67% in middle-income countries (MIC). Sixty-nine percent of HIC demonstrated a decline in RBP against 15% in MIC. CVD management, tobacco, and unhealthy diet reduction measures are significantly better in HIC. The air pollution level was higher in MIC.Conclusion: Building partnerships between countries could enhance their efforts for CVD prevention and successful achievement of SDG.展开更多
The Global Alliance Against Chronic Respiratory Diseases(GARD)is a voluntary alliance of national and international organizations,institutions,and agencies committed to the vision of "a world where all people bre...The Global Alliance Against Chronic Respiratory Diseases(GARD)is a voluntary alliance of national and international organizations,institutions,and agencies committed to the vision of "a world where all people breathe freely"Its goal is to reduce the global burden of chronic respiratory disease(CRD).The GARD initiative was set up to respond to a resolution of the World Health Assembly in May 2000(Resolution WHA53.17)that emphasized the need to increase awareness of the growing epidemic of CRDs worldwide.A program was begun to design a comprehensive approach to the prevention and control of CRDs.11,21 The resolution was approved by the General Assembly of World Health Organization(WHO)in 2004.展开更多
文摘Races using kitefoil and windfoil surfboards have been in the Olympic Games for the first time in Paris 2024,signalling their relevance in sailing sports.However,the dynamics of these devices is yet not well understood,in particular the influence on the hydrodynamic forces and moments of the distance of the foil to the free surface.Considering this,the present paper documents an experimental investigation in which forces and torque produced,under uniform flow,by a full-scale state-of-the-art hydrofoil(suitable both for kitesurf and windsurf)were measured.A range of velocities,angles of attack,and submergences were tested,leading to Froude numbers based on submergence with maximum values around five,a typical range in actual sailing conditions.From these tests,formulae for the hydrodynamic coefficients have been proposed.They can be used for developing Velocity Prediction Programs(VPP)for this kind of craft,a necessary tool to plan racing configurations and to analyze their racing performance.With the aim of making the experimental data useful for benchmarking numerical models and for future research on related topics such as foil ventilation and transition to turbulence,the specimen’s 3D file is provided as supplementary material to this paper.
基金This research was supported by the National Natural Science Foundation of China （N0.70373044 ＆ 30470302） and Ph.D. Startup Found from Institute of Applied Ecology. Chinese Academy of Sciences.
文摘Based on the tree-ring growth characteristics of Erman＇s birch （Betula ermanii charm.） and the relationships between it and climatic ）＇actors at elevation of 1950m, the sensitivity of tree lines in Changbai Mountain to climatic factors was assessed. The results indicated tree line forest in Changbai Mountain had an obvious sensitivity to climate factors. However, difference from other study sits is that the main climatic control factor on tree-ring growth was not current growth season temperatures, as might be expected, but previous winter and current March temperature. Although the precipitation in the region was quite abundant, the tree-ring growth was still significantly correlated with the precipitation during previous winter and current spring. Additionally, climatic factors which influenced the Erman＇s birch growth were not the yearly variables, but seasonal and monthly variables. Therefore, the reported increase in yearly mean temperature and total yearly precipitation since 1980s was not responded by sustained increase in ring widths in recent decades.
文摘The composition of ashes stemming from the burning of medical waste is similar to that of urban waste. Specific pieces of evidence are looked for that allowed distinguishing some components in those waste products. A selection is carried out and some elements are included in a glass matrix. An unexpected result is presented here. It is possible to differentiate sterile and non-sterile medical gloves. The main difference is the relative amounts of calcium, in glass forming. Glasses are manufactured with a mono-ammonium phosphate since it is a natural product in Morocco. Several compositions are tried and studied. These compositions are expressed in usual two ternary and one quaternary systems built with the four equivalent components： SiO2, A1203, P205 and CaO and then compared to a patented composition.
文摘Greywater, a type of wastewater, may be hazardous to human health and ecosystems. Greywater is a large fraction of wastewater that needs adequate attention for remediation and reuse in the agricultural sector so that a part of the water problem can be sorted out. This study aims to develop a rapid method for greywater treatment and reuse in agriculture. A microfilter consisting of sand, clay, organo-clay, charcoal, and biochar was designed and tested for greywater treatments. Biological Oxygen Demand (BOD), Chemical Oxygen Demand (COD), Total Kjeldahl Nitrogen (TKN), Total Dissolved Salts (TDS), Electric Conductivity (EC), turbidity and pH values were measured before and after using the microfilter. Results showed tremendous removal efficiency of BOD, COD, TKN, by using the developed microfilter. The microfilter was also effective in treating and placing pH, EC and TDS in the acceptable range for suitable agricultural use. Using the treated greywater for irrigation in corn, tomato seedlings showed increased growth compared with the control group (plants irrigated with tap water). This microfilter treatment was economical, safe, easy to handle and easily applicable. These encouraging results suggest the application of this method in many countries for solving the water scarcity problem.
文摘Depuis2001,et conform ment nos engagements aupr s de la population,la municipalit que j ai I honneur de conduire a mis en oeuvre une politique destin e 《faire revivre N⒌mes》. Cela s est d j traduit dans des domaines tr s sensibles localement comme la s curit des biens et des personˉnes,la propret des espaces publics,la qualit et la diversit des animations-qu elles soient culturelles,festives ou sportives-,l accueil de nouvelles entreprises...
基金supported by the Institute for Marine and Antarctic Studies (IMAS, University of Tasmania), which hosts the SOOS International Project Officesponsored by numerous international organizations (www.soos.aq/index.php/about-us/sponsors)
文摘Despite recent progress in deep-sea biodiversity assessments in the Southern Ocean （SO）, there remain gaps in our knowledge that hamper efficient deep-sea monitoring in times of rapid climate change. These include geographical sampling bias, depth and size-dependent faunal gaps in biology, ecology, distribution, and phylogeography, and the evolution of SO species. The phenomena of species patchiness and rarity are still not well understood, possibly because of our limited understanding of physiological adaptations and thresholds. Even though some shallow water species have been investigated physiologically, community-scale studies on the effects of multiple stressors related to ongoing environmental change, including temperature rise, ocean acidification, and shifts in deposition of phytoplankton, are completely unknown for deep-sea organisms. Thus, the establishment of long-term and coordinated monitoring programs, such as those rapidly growing under the umbrella of the Southern Ocean Observing System （SOOS） or the Deep Ocean Observing Strategy （DOOS）, may represent unique tools for measuring the status and trends of deep-sea and SO ecosystems.
文摘Background/Aims: Egypt has the highest prevalence of Hepatitis C Virus (HCV) in the world, aPPArently due to mass parenteral antischistosomal therapy. Estimating the future burden of HCV in Egypt is important to support health policies to combat the epidemic. Methods: A previous back calculation model was adapted to the situation in Egypt. It combines a model of the natural history of HCV infections with available epidemiological data to back calculate the past HCV incidence from observed 1980- 1999 hepatocellular carcinoma (HCC) mortality. In turn, the HCV-related mortality burden is projected in the future due to pre- 2000 infections. Results: Compared with the observed number of HCC deaths in 1999, the model predicts a 3.5- fold increase in this mortality in the next 20 years. Globally, the model predicts a 2.4- fold increase in theHCV-related mortality. These predictions do not take into account the new infections that may occur after 2000, which would still increase the estimated future mortality burden. Conclusions: HCV-related mortality is expected at least to double in the next 20 years. The use of antiviral therapies can lower these predictions. Efficient prevention policies are needed to avoid these predictions being exceeded.
文摘The Voigt function is the convolution of a Lorentzian and a Guaussian density. The computation of these functions is required in several problems arising in a variety of physicochemical subjects;such as nuclear reactors, atmospheric transmittance and spectroscopy. In this work we suggest using a new formula for the calculation of the Voigt function. Our formula is a new integral representation for the Voigt function that gives the perfect results for the Voigt function calculation and is easily calculable. We give also a comparison between our results of calculation of Voigt function for the very small values of the parameter a, where the calculation is notoriously difficult, with those of the various algorithms of other authors.
基金the Conseil Regional of PACA,the Conseil Général du Var,and Toulon Provence Mediterranean for their financial support.
文摘Carbon nanotubes flower(CNTs-F)films were prepared by catalytic chemical vapor deposition(CVD)on a platinum(Pt)thin layer,supported on a silicon wafer.The products were synthesized from an aerosol composed of ferrocene and toluene,as catalyst and carbon precursor respectively,at 820.The high synthesis temperature induces a modification of a Pt thin layer to a nano-structured island giving rise to the formation of CNTs-F during the following films growth step by CVD process.The suggested mechanism involves the selective diffusion of the catalyst and carbon atoms through the Pt grain boundaries.This results in the appearance of flower-like structures with 3-and 4-fold symmetries.
文摘Aims: To identify factors, which were related to being smoke-free and snus-free, respectively, among adolescents in relation to adolescents who were smoking and/or using snus, and determine if there were any sex differences. Methods: A questionnaire study was performed among students in year two in upper secondary schools (17-years-old) in southern Sweden in 2009. More than 2200 students completed the questionnaire regarding health and living habits anonymously. The variables were tested by χ2-test, before selection into the logistic model. Because of the salutogenic approach in the study, the results of the logistic regression analyses were expressed as Positive Odds Ratio (POR). Results: The prevalence of being smoke- free was 75.6 percent for girls and 70.2 percent for boys, whilst the prevalence of being snus- free was 95.1 percent for girls and 70.2 percent for boys. Having a tobacco-free best friend was the most important factor that correlated with being smoke- and snus-free as an adolescent, for both boys and girls. Good living habits, such as drinking less alcohol, were also central to being smoke-free and snus-free. Conclusions: The results show that a tobacco-free environment has a great influence on whether or not adolescents stay tobacco-free. As the environment has a big impact, the school has a big challenge to work with the school environment and policies but also with family responsibility, norms and attitudes to tobacco.
文摘The communication system known as quorum sensing (QS) in gram-negative bacteria regulates biofilm formation and many other functions. The particularity of Pseudoalteromonas ulvae TC14 seems to be the absence of a LuxI inducer, and therefore the lack of production of small molecules of Acyl homoserine lactone (AHL). Previous studies had shown that it does not harbor the inducer of the regulatory molecule (AHL). Nevertheless, it is able to regulate these same functions (biofilm, violacein) via AHLs. This could mean the presence of specific receptors for these induction molecules, belonging to the LuxR family. The aim of this study was to test these hypotheses using molecular analysis. Genome sequencing of the P. ulvae TC14 strain was carried out by Molecular Research LP (MR DNA), using the Illumina Hiseq 2500 method. The results revealed the presence of 2,293,242 base pairs, i.e. 100% of the genomic volume. The number of coding gene sequences was 1983, and the Guanine + Cytosine (G+C) percentage of the base number was 41.55%, revealing stability in the sequenced genome. In order to verify the identity of the sequenced genome, a phylogenetic analysis based on RNA16S was carried out. This analysis resulted in 93% homology with the previously sequenced and characterized species Pseudoalteromonas tunicata, showing that it belongs to the genus Pseudoalteromonas. To these comparative results should be added those derived from genome analysis based on nucleotide percentage using the tools available at https://img.jgi.doe.gov/. The results showed that Pseudoalteromonas tunicata D2 has the highest percentage nucleotide identity (ANI) (75.7913%), followed by Pseudoalteromonas flavipulchra NCIMB2033 (72.2736%) and Pseudoalteromonas phenolica KCTC 12086 (71.6685%). Next, the search for the various genes involved in QS was carried out using sequence comparisons via the BLAST method. For LuxI, sequence templates from the genomes of Vibrio, Chromobacterium, Shewanella or even other Pseudoalteromonas species were screened against the TC14 genome. This yielded no conclusive results synonymous with the non-presence of LuxI in TC14 as assumed by previous research. The search for LuxR, on the other hand, gave rise to the presence of eight presumptive sequences. Molecular characterization of the presumptive LuxR sequences was carried out to assess their gene expression. This characterization showed expression of these LuxR homologous sequences in a range from o.11 to 5.33 picograms (pg). Even if these sequences were not analyzed in depth, the retro-transcription technique nevertheless showed a minimum of activity, which could enable us to distinguish them from inactive sequences. The next step was to compare the LuxRs found in TC14 with the so-called Solo LuxRs, which act autonomously. This study shows that P. ulvae TC14 is a bacterium with a particular LuxR-based communication system.
基金supported by the ADEN-MED project(Adaptability to Extreme events and Natural risks-application to the Mediterranean and Djibouti),funded by the Region Sud Provence-Alpes-Cote d’Azur under the AAP MEDCLIMAT“Natural risks and food sovereignty”by France 2030 through the Priority Research Program and Equipment(PEPR)“Maths-Vives-Mathematics in Interactions”,targeted project HYDRAUMATH(ANR-23-EXMA-007),operated by ANR.
文摘In this article,we study the convergence of an IIPG(Incomplete Interior Penalty Galerkin)Discontinuous Galerkin numerical method for the Richards equation.The Richards equation is a degenerate parabolic nonlinear equation for modeling flows in porous media with variable saturation.The numerical solution of this equation is known to be difficult to calculate numerically,due to the abrupt displacement of the wetting front,mainly as a result of highly nonlinear hydraulic properties.As time scales are slow,implicit numerical methods are required,and the convergence of nonlinear solvers is very sensitive.We propose an original method to ensure convergence of the numerical solution to the exact Richards solution,using a technique of auto-calibration of the penalty parameters derived from the Galerkin Discontinuous method.The method is constructed using nonlinear 1D and 2D general elliptic problems.We show that the numerical solution converges toward the unique solution of the continuous problem under certain conditions on the penalty parameters.Then,we numerically demonstrate the efficiency and robustness of the method through test cases with analytical solutions,laboratory test cases,and large-scale simulations.
基金supported by the ADEN-MED project(Adaptability to Extreme Events and Natural Risks-Application to the Mediterranean and Djibouti)funded by the Région Sud Provence-Alpes-Côte d’Azur under the AAP MEDCLIMAT“Natural Risks and Food Sovereignty”.
文摘We propose a new section-averaged one-dimensional model for blood flows in deformable arteries.The model is derived from the three-dimensional Navier-Stokes equations,written in cylindrical coordinates,under the“thin-artery”assumption(similar to the“shallow-water”assumption for free surface models).The blood flow/artery interaction is taken into account through suitable boundary conditions.The obtained equations enter the scope of the nonlinear convection-diffusion problems.We show that the resulting model is energetically consistent.The proposed model extends most extant models by adding more scope,depending on an additional viscous term.We compare both models computationally based on an Incomplete Interior Penalty Galerkin(IIPG)method for the parabolic part,and on a Runge Kutta Discontinuous Galerkin(RKDG)method for the hyperbolic part.The time discretization explicit/implicit is based on the well-known Additive Runge-Kutta(ARK)method.Moreover,through a suitable change of variables,by construction,we show that the numerical scheme is well-balanced,i.e.,it preserves exactly still-steady state solutions.To end,we numerically investigate its efficiency through several test cases with a confrontation to an exact solution.
文摘We propose a new two-dimensional blood flow reduced model taking into account of complex artery geometry as in the case of severe aneurysm.We derive the model from the three-dimensional Navier-Stokes equations written in a curvilinear coordinate system under the thin-artery assumption,with boundary conditions including wall tissue deformation.We show that the model is energetically consistent with the full Navier-Stokes problem.This model,obtained via radial averaging,is,up to our knowledge,the first one.It has the advantage of being more accurate than the classical one-dimensional models and being solved in a reasonable time in comparison with the Navier-Stokes models.To this purpose,we use a Runge-Kutta Discontinuous Galerkin(RKDG)method to solve the two-dimensional problem.We end the paper with several numerical test cases to show the efficiency and robustness of the numerical model,and in particular,we show the limit of the one-dimensional models in the case of a severe aneurysm.
文摘We investigate a version of one velocity Baer-Nunziato model with dissipation for the mixture of two compressible fluids with the goal to prove for it the existence of weak solutions for arbitrary large initial data on a large time interval.We transform the one velocity Baer-Nunziato system to another"more academic"system which possesses the clear"Navier-Stokes structure".We solve the new system by adapting to its structure the Lions approach for solving the(mono-fluid)compressible Navier-Stokes equations.An extension of the theory of renormalized solutions to the transport equation to more continuity equations with renormalizing functions of several variables is essential in this process.We derive a criterion of almost uniqueness for the renormalized solutions to the pure transport equation without the classical assumption on the boundedness of the divergence of the transporting velocity.This result does not follow from the DiPerna-Lions transport theory and it is of independent interest.This criterion plays the crucial role in the identification of the weak solutions to the original one velocity Baer-Nunziato problem starting from the weak solutions of the academic problem.As far as we know,this is the first result on the existence of weak solutions for a version of the one velocity bi-fluid system of the Baer-Nunziato type in the mathematical literature.
文摘Background: Cardiovascular disease (CVD) is the major noncommunicable disease (NCD) accounting for 17.9 million deaths. If current trends continue, the annual number of deaths from CVD will rise to 22.2 million by 2030. The United Nations General Assembly adopted a sustainable development goal (SDG) by 2030 to reduce NCD mortality by one-third. The purpose of this study was to analyze the CVD mortality trends in different countries implementing World Health Organization (WHO) NCD Action Plan and emphasize effective ways to achieve SDG.Methods: WHO statistics, based on the Member-States unified mortality and causes-of-death reports were used for analyzing trends and different interventions.Results: Reduction of CVD mortality from 2000 to 2016 in 49 countries was achieved for stroke at 43% and ischemic heart disease at 30%. Smoking prevalence and raised blood pressure (RBP) decreased in 84% and 55% of the countries. Eighty-nine percent of high-income countries (HIC) demonstrated a decline in tobacco smoking against 67% in middle-income countries (MIC). Sixty-nine percent of HIC demonstrated a decline in RBP against 15% in MIC. CVD management, tobacco, and unhealthy diet reduction measures are significantly better in HIC. The air pollution level was higher in MIC.Conclusion: Building partnerships between countries could enhance their efforts for CVD prevention and successful achievement of SDG.
文摘The Global Alliance Against Chronic Respiratory Diseases(GARD)is a voluntary alliance of national and international organizations,institutions,and agencies committed to the vision of "a world where all people breathe freely"Its goal is to reduce the global burden of chronic respiratory disease(CRD).The GARD initiative was set up to respond to a resolution of the World Health Assembly in May 2000(Resolution WHA53.17)that emphasized the need to increase awareness of the growing epidemic of CRDs worldwide.A program was begun to design a comprehensive approach to the prevention and control of CRDs.11,21 The resolution was approved by the General Assembly of World Health Organization(WHO)in 2004.
