Ulcerative colitis(UC)is a chronic disease characterized by diffuse inflammation of the mucosa of the colon and rectum.The hallmark clinical symptom of UC is bloody diarrhea.The clinical course is marked by exacerbati...Ulcerative colitis(UC)is a chronic disease characterized by diffuse inflammation of the mucosa of the colon and rectum.The hallmark clinical symptom of UC is bloody diarrhea.The clinical course is marked by exacerbations and remissions,which may occur spontaneously or in response to treatment changes or intercurrent illnesses.UC is most commonly diagnosed in late adolescence or early adulthood,but it can occur at any age.The incidence of UC has increased worldwide over recent decades,especially in developing nations.In contrast,during this period,therapeutic advances have improved the life expectancy of patients,and there has been a decrease in the mortality rate over time.It is important to emphasize that there is considerable variability in the phenotypic presentation of UC.Within this context,certain clinical and demographic characteristics are useful in identifying patients who tend to have more severe evolution of the disease and a poor prognosis.In this group of patients,better clinical surveillance and more intensive therapy may change the natural course of the disease.The aim of this article was to review the epidemiology and demographic characteristics of UC and the factors that may be associated with its clinical prognosis.展开更多
The present paper is an attempt to define the contours of the right macroeconomic strategy for China. In a nutshell, we believe that the package includes a decrease in saving, with a focus on private saving, an increa...The present paper is an attempt to define the contours of the right macroeconomic strategy for China. In a nutshell, we believe that the package includes a decrease in saving, with a focus on private saving, an increase in the supply of services, in particular health services, and an appreciation of the RMB. This is why we refer to this strategy as a ＂three-handed approach ＂： action on the fiscal and budgetary front, accompanied by currency revaluation. We start by asking how the Chinese economy got to where it is, what the strategy has been since the beginning of the reforms, and what the main characteristics of the economy are today. We then ask what is the desirable path for the future, and which are the main policy trade-offs implied by such a path. Finally, we put the various pieces together to describe what we believe is a consistent policy package.展开更多
This paper considers the issue of local ＂land finance＇＂ in the context of China ＂s fast urban expansion. In an analysis of China ＂s land requisition and public leasing system we argue that low-cost land acquisiti...This paper considers the issue of local ＂land finance＇＂ in the context of China ＂s fast urban expansion. In an analysis of China ＂s land requisition and public leasing system we argue that low-cost land acquisition is the fundamental cause of land-related distortions that have occurred during China ＂s urbanization. Granting farmers the power to negotiate directly with land users during urban expansion, combined with coordinated land tax reforms to consolidate local tax bases is the key to China achieving both equity and land use efficiency in urban expansion.展开更多
Mesenteric ischemia disorders are precipitated by a circulation insufficiency event that deprives one or several abdominal organs of adequate respiration to meet metabolic demands. Although mesenteric ischemia occurs ...Mesenteric ischemia disorders are precipitated by a circulation insufficiency event that deprives one or several abdominal organs of adequate respiration to meet metabolic demands. Although mesenteric ischemia occurs infrequently, the mortality rate is from 60% to 100%, depending on the source of obstruction. The successful outcome is dependent upon a high index of suspicion and prompt management. We briefly review the pathophysiology and presentation of the various ischemic entities and review the current state of the art in diagnosis and treatment. Despite advances in both diagnosis and treatment, prompt diagnosis and supportive care remain critical for successful outcome. New imaging techniques, endovascular therapy and emerging research may improve our approach to this deadly condition.展开更多
This paper emphasizes the importance of the denomination of financial assets rather than trade invoicing as a long-term determinant of an international currency. China needs to liberalize and open its financial system...This paper emphasizes the importance of the denomination of financial assets rather than trade invoicing as a long-term determinant of an international currency. China needs to liberalize and open its financial system and make the RMB fully convertible, and to adopt a moreflexible exchange rate system to speed up its currency internationalization, for which China could follow either a global or regional approach. The global approach is a riskier and more unpredictable strategy because it would demand a scope and timeframe of financial liberalization that is likely to be beyond China＇s institutional capacity over the coming decade. There are two options that could be taken in following the regional approach. One is creating an ASEAN＋ New 3 （the Chinese Mainland, Hong Kong, and Taiwan） RMB bloc and the other is liberalizing China＇s financial industries and internationalizing the RMB by playing a leading role in East Asia＇s economic integration within the framework of ASEAN＋ 3, This paper concludes that the latter is a more realistic and effective approach for China.展开更多
INTRODUCTIONThe“nonspecific” inflammatory bowel diseases ,ulcerative colitis and Crohn,s represent a group of heterogeneous inflammatory and ulcerative disases of the small and large intestines of unknown etiology ,...INTRODUCTIONThe“nonspecific” inflammatory bowel diseases ,ulcerative colitis and Crohn,s represent a group of heterogeneous inflammatory and ulcerative disases of the small and large intestines of unknown etiology ,associated with many gastrointestinal and systemic complications .Appearing initially as isolated cases in Great Britain and northern Europe during the 19th and early 20th centuries ,they have steadily increased numerically and geographically and today are recognized worldwide.展开更多
From the perspective of conditional convergence, China＇s GDP growth rate since 1990 has been surprisingly high. However, China cannot deviate forever from the global historical experience, and the per capita growth r...From the perspective of conditional convergence, China＇s GDP growth rate since 1990 has been surprisingly high. However, China cannot deviate forever from the global historical experience, and the per capita growth rate is likely to fall soon from around 8 percent per year to a range of 3-4 percent. China can be viewed as a middle-income convergence success story, grouped with Costa Rica, Indonesia, Peru, Thailand and Uruguay. Upper-income convergence successes （toward which China is likely heading） include Chile, Hong Kong, Ireland, Malaysia, Poland, Singapore, South Korea and Taiwan.展开更多
The present study aims to give general hints about hydrodynamic interactions for water wave diffraction on a super large floating structure composed of a large number of box-shaped modules with many small gaps in betw...The present study aims to give general hints about hydrodynamic interactions for water wave diffraction on a super large floating structure composed of a large number of box-shaped modules with many small gaps in between. And meanwhile, it also aims to seek for an effective way to take the gap influence into consideration without numerical difficulties existing in conventional methods. An asymptotic matching technique is exploited by virtue of the smallness of gaps. Formal potential solutions are established for the near field around the gap ends and the far field away from gap ends, respectively, and the unknowns in those solutions are uniquely determined by asymptotic matching. The eigen-function expansion method is used for the outer far field and a series of pulsating sources at each gap end is introduced to simulate the gap influence. Strong hydrodynamic interaction is observed and a new resonant phenomenon, the mechanism of which differs absolutely from any known ones, is revealed in the present study. Sharp peak responses for both vertical and horizontal wave-exciting forces on each block are found around some special resonance frequencies, which depend on the draft of the structure and the gap width. The present results are of practical significance to the design of links (connectors) of modules for super large floating structures. And the importance is also closely related to the hydro-elasticity analysis for super large floating structures, in which local loads may be as important as the integrated loads.展开更多
Surgery used to be the only therapy for gastric cancer, and since its ability to cure gastric cancer was the focus of attention, less attention was paid to functionpreserving surgery in gastric cancer, though it was s...Surgery used to be the only therapy for gastric cancer, and since its ability to cure gastric cancer was the focus of attention, less attention was paid to functionpreserving surgery in gastric cancer, though it was studied for gastroduodenal ulcer. Maki et al developed pylorus-preserving gastrectomy for gastric ulcer in 1967. At the same time, the definition of early gastric cancer(EGC) was being considered, histopathological investigations of EGC were carried out, and the validity of modified surgery was sustained. After the development of H2-blockers, the number of operations for gastroduodenal ulcers decreased, and the number of EGC patients increased simultaneously. As a result, the indications for pylorus-preserving gastrectomy for EGC in the middle third of the stomach extended, and various alterations were added. Since then, many kinds of function-preserving gastrectomies have been performed and studied in other fields of gastric cancer, and proximal gastrectomy, jejunal pouch interposition, segmental gastrectomy, and local resection have been performed. On the other hand, from the overall perspective, it can be said that endoscopic resection, which was launched at almost the same time, is the ultimate function-preserving surgery under the current circumstances. The current function-preserving gastrectomies that are often performed and studied are pylorus-preserving gastrectomy and proximal gastrectomy. The reasons for this are that these procedures that can be performed with systemic lymph node dissection, and they include three important elements:(1) reduction of the extent of gastrectomy;(2) preservation of the pylorus; and(3) preservation of the vagal nerve. In addition, these operations are more likely to be performed with a laparoscopic approach as minimally invasive surgery. Of the above-mentioned three elements, reduction of the extent of gastrectomy is the most important in our view. Therefore, we should try to reduce the extent of gastrectomy if curability of the gastric cancer can still be achi展开更多
This paper reviews the development of the urban and rural old age security system in China, and discusses the challenges in the process of constructing a sustained old age security system. Althoughfunding gaps and emp...This paper reviews the development of the urban and rural old age security system in China, and discusses the challenges in the process of constructing a sustained old age security system. Althoughfunding gaps and empty individual accounts have imposed a heavy burden on the sustainability of China ＇s urban pension system, there is a relatively high coverage rate of 35.3 percent for urban workers. However, China＇s pension system provides low coverage ratefor rural farmers. The more rapidly aging population and lower incomes in rural areas pose challenges to the vulnerable rural househoM support system. The separation of the oM age security system between rural and urban areas also puts great pressure as a result of urbanization on farmers who lose their farmland. Therefore, it is urgent for China to speed up the reform o fits old age security system to provide an institutional support for its economic and social transition.展开更多
This paper presents the optimal design procedure of Tuned Mass Damper (TMD) for reducing vibration of an actual steel jacket offshore platform excited by random wave loading. In this study, a frequency domain is taken...This paper presents the optimal design procedure of Tuned Mass Damper (TMD) for reducing vibration of an actual steel jacket offshore platform excited by random wave loading. In this study, a frequency domain is taken. The force on the structure is determined by use of the linearized Morison equation for an input Power Spectral Density (PSD) of wave elevation. The sensitivity of optimum values of TMD to characteristic parameters of random wave spectrum is analyzed. An optimized TMD design for the modeled platform is given based on design conditions and the findings of the study.展开更多
Present-day advanced technologies heavily rely on the exciting magnetic and spectroscopic properties of lanthanide ions. In particular, their ability to generate well-characterized and intense near-infrared (NIR) lumi...Present-day advanced technologies heavily rely on the exciting magnetic and spectroscopic properties of lanthanide ions. In particular, their ability to generate well-characterized and intense near-infrared (NIR) luminescence is exploited in any modern fiber-optic telecommunication network. In this feature article, we first summarize the whereabouts underlying the design of highly luminescent NIR molecular edifices and materials. We then focus on describing the main trends in three applications related to this spectral range: telecommunications, biosciences, and solar energy conversion. In telecommunications, efforts concentrate presently on getting easily processable polymer-based waveguide amplifiers. Upconversion nanophosphors emitting in the visible after NIR excitation are now ubiquitous in many bioanalyses while their application to bio-imaging is still in its early stages; however, highly sensitive NIR-NIR systems start to be at hand for both in vitro and in vivo imaging, as well as dual probes combining magnetic resonance and optical imaging. Finally, both silicon-based and dye-sensitized solar cells benefit from the downconversion and upconversion capabilities of lanthanide ions to harvest UV and NIR solar light and to boost the overall quantum efficiency of these next-generation devices.展开更多
AIM： To assess the efficacy and safety of Saccharomyces boulardii （S. boulardii） in acute watery diarrhoea and its role in reducing the frequency of episodes of diarrhoea in subsequent two months. METHODS： Childre...AIM： To assess the efficacy and safety of Saccharomyces boulardii （S. boulardii） in acute watery diarrhoea and its role in reducing the frequency of episodes of diarrhoea in subsequent two months. METHODS： Children from 2 mo to 12 years of age, with acute diarrhoea were selected according to inclusion criteria and randomised in S. boulardii group （treated with ORS, nutritional support and S. boulardii, 250 mg bid） and in control group （treated with ORS and nutritional support only）. Active treatment phase was 5 d and each child was followed for two months afterwards. Frequency and consistency of stools as well as safety of drug was assessed on every visit. A comparison of two groups was done in terms of number of diarrhoeal episode in subsequent two months. RESULTS： There were fifty patients in each group. Baseline characteristics such as mean age and the average frequency of stools were comparable in S. boulardii and control group at the time of inclusion in the trial. By d 3 it reduced to 2.7 and 4.2 stools per d respectively and by d 6 it reduced to 1.6 （5. boulardii Group） and 3.3 （control group）. The duration of diarrhoea was 3.6 d in S. boulardii group whereas it was 4.8 d in control group （P = 0.001）. In the following two months, S. boulardii group had a significantly lower frequency of 0.54 episodes as compared to 1.08 episodes in control group. The drug was well accepted and tolerated. There were no reports of the side effects during treatment period CONCLUSION： S. boulardii significantly reduces the frequency and duration of acute diarrhoea. The consistency of stool also improves. The drug is well-tolerated.展开更多
The wave propagation behavior in an elastic wedge-shaped medium with an arbitrary shaped cylindrical canyon at its vertex has been studied.Numerical computation of the wave displacement field is carried out on and nea...The wave propagation behavior in an elastic wedge-shaped medium with an arbitrary shaped cylindrical canyon at its vertex has been studied.Numerical computation of the wave displacement field is carried out on and near the canyon surfaces using weighted-residuals(moment method).The wave displacement fields are computed by the residual method for the cases of elliptic,circular,rounded-rectangular and flat-elliptic canyons,The analysis demonstrates that the resulting surface displacement depends,as in similar previous analyses,on several factors including,but not limited,to the angle of the wedge,the geometry of the vertex,the frequencies of the incident waves,the angles of incidence,and the material properties of the media.The analysis provides intriguing results that help to explain geophysical observations regarding the amplification of seismic energy as a function of site conditions.展开更多
Few studies of wave propagation in layered saturated soils have been reported in the literature.In this paper,a general solution of the equation of wave motion in saturated soils,based on one kind of practical Blot...Few studies of wave propagation in layered saturated soils have been reported in the literature.In this paper,a general solution of the equation of wave motion in saturated soils,based on one kind of practical Blot's equation, was deduced by introducing wave potentials.Then exact dynamic-stiffness matrices for a poroelastic soil layer and half- space were derived,which extended Wolf's theory for an elastic layered site to the case of poroelasticity,thus resolving a fundamental problem in the field of wave propagation and soil-structure interaction in a poroelastic layered soil site.By using the integral transform method,Green's functions of horizontal and vertical uniformly distributed loads in a poroelastic layered soil site were given.Finally,the theory was verified by numerical examples and dynamic responses by comparing three different soil sites.This study has the following advantages:all parameters in the dynamic-stiffness matrices have explicitly physical meanings and the thickness of the sub-layers does not affect the precision of the calculation which is very convenient for engineering applications.The present theory can degenerate into Wolf's theory and yields numerical results approaching those for an ideal elastic layered site when porosity tends to zero.展开更多
Endoscopic retrograde cholangiopancreatography(ERCP) has a significant complication rate which can be lowered by adopting technical variations of proven beneficial effect and prophylactic maneuvers such as pancreatic... Endoscopic retrograde cholangiopancreatography(ERCP) has a significant complication rate which can be lowered by adopting technical variations of proven beneficial effect and prophylactic maneuvers such as pancreatic stenting during ERCP or periprocedural non-steroidal anti-inflammatory drug administration.However,adoption of these prophylactic maneuvers by endoscopists is not uniform.In this editorial we discuss the beneficial effects of the aforementioned maneuvers.展开更多
The emergence of a digital divide or a lack of internet access may hinder urbanization and adversely affect growth.However,fintech development can help to improve the accessibility and affordability of financial servi...The emergence of a digital divide or a lack of internet access may hinder urbanization and adversely affect growth.However,fintech development can help to improve the accessibility and affordability of financial services,particularly for sections of the population formerly excluded from such services.Improved access is expected to stimulate the growth essential for promoting urbanization,possibly alleviating the negative impacts of a digital divide and creating a trickle-down effect.This paper is among the first to investigate the effect of fintech development on urbanization,as indicated by labor transfer from agricultural to non-agricultural sectors in China.It is found that:(i)the digital divide hindered,while fintech development contributed to urbanization;(ii)the positive effect of fintech development on urbanization affects individuals both with and without access to the internet,yielding the so-called trickledown ejfect and thus helping to alleviate the negative consequences of a digital divide;and(Hi)regarding transmission mechanisms,fintech development helps to generate additional jobs and raise income in non-agricultural sectors,stimulating urbanization even for those without access to the internet.展开更多
文摘Ulcerative colitis(UC)is a chronic disease characterized by diffuse inflammation of the mucosa of the colon and rectum.The hallmark clinical symptom of UC is bloody diarrhea.The clinical course is marked by exacerbations and remissions,which may occur spontaneously or in response to treatment changes or intercurrent illnesses.UC is most commonly diagnosed in late adolescence or early adulthood,but it can occur at any age.The incidence of UC has increased worldwide over recent decades,especially in developing nations.In contrast,during this period,therapeutic advances have improved the life expectancy of patients,and there has been a decrease in the mortality rate over time.It is important to emphasize that there is considerable variability in the phenotypic presentation of UC.Within this context,certain clinical and demographic characteristics are useful in identifying patients who tend to have more severe evolution of the disease and a poor prognosis.In this group of patients,better clinical surveillance and more intensive therapy may change the natural course of the disease.The aim of this article was to review the epidemiology and demographic characteristics of UC and the factors that may be associated with its clinical prognosis.
文摘The present paper is an attempt to define the contours of the right macroeconomic strategy for China. In a nutshell, we believe that the package includes a decrease in saving, with a focus on private saving, an increase in the supply of services, in particular health services, and an appreciation of the RMB. This is why we refer to this strategy as a ＂three-handed approach ＂： action on the fiscal and budgetary front, accompanied by currency revaluation. We start by asking how the Chinese economy got to where it is, what the strategy has been since the beginning of the reforms, and what the main characteristics of the economy are today. We then ask what is the desirable path for the future, and which are the main policy trade-offs implied by such a path. Finally, we put the various pieces together to describe what we believe is a consistent policy package.
基金the Chinese Ministry of Science and Technology Key Technologies R&D Program (2006BAJ11B06)the China National Science Foundation (70633002)the Lincoln Institute for Land Policy for financial support
文摘This paper considers the issue of local ＂land finance＇＂ in the context of China ＂s fast urban expansion. In an analysis of China ＂s land requisition and public leasing system we argue that low-cost land acquisition is the fundamental cause of land-related distortions that have occurred during China ＂s urbanization. Granting farmers the power to negotiate directly with land users during urban expansion, combined with coordinated land tax reforms to consolidate local tax bases is the key to China achieving both equity and land use efficiency in urban expansion.
文摘Mesenteric ischemia disorders are precipitated by a circulation insufficiency event that deprives one or several abdominal organs of adequate respiration to meet metabolic demands. Although mesenteric ischemia occurs infrequently, the mortality rate is from 60% to 100%, depending on the source of obstruction. The successful outcome is dependent upon a high index of suspicion and prompt management. We briefly review the pathophysiology and presentation of the various ischemic entities and review the current state of the art in diagnosis and treatment. Despite advances in both diagnosis and treatment, prompt diagnosis and supportive care remain critical for successful outcome. New imaging techniques, endovascular therapy and emerging research may improve our approach to this deadly condition.
文摘This paper emphasizes the importance of the denomination of financial assets rather than trade invoicing as a long-term determinant of an international currency. China needs to liberalize and open its financial system and make the RMB fully convertible, and to adopt a moreflexible exchange rate system to speed up its currency internationalization, for which China could follow either a global or regional approach. The global approach is a riskier and more unpredictable strategy because it would demand a scope and timeframe of financial liberalization that is likely to be beyond China＇s institutional capacity over the coming decade. There are two options that could be taken in following the regional approach. One is creating an ASEAN＋ New 3 （the Chinese Mainland, Hong Kong, and Taiwan） RMB bloc and the other is liberalizing China＇s financial industries and internationalizing the RMB by playing a leading role in East Asia＇s economic integration within the framework of ASEAN＋ 3, This paper concludes that the latter is a more realistic and effective approach for China.
文摘INTRODUCTIONThe“nonspecific” inflammatory bowel diseases ,ulcerative colitis and Crohn,s represent a group of heterogeneous inflammatory and ulcerative disases of the small and large intestines of unknown etiology ,associated with many gastrointestinal and systemic complications .Appearing initially as isolated cases in Great Britain and northern Europe during the 19th and early 20th centuries ,they have steadily increased numerically and geographically and today are recognized worldwide.
文摘From the perspective of conditional convergence, China＇s GDP growth rate since 1990 has been surprisingly high. However, China cannot deviate forever from the global historical experience, and the per capita growth rate is likely to fall soon from around 8 percent per year to a range of 3-4 percent. China can be viewed as a middle-income convergence success story, grouped with Costa Rica, Indonesia, Peru, Thailand and Uruguay. Upper-income convergence successes （toward which China is likely heading） include Chile, Hong Kong, Ireland, Malaysia, Poland, Singapore, South Korea and Taiwan.
基金Project supported by the National Natural Science Foundation of China(Grant No.59879011 and 19732004)the Foundation of the Ministry of Education of China
文摘The present study aims to give general hints about hydrodynamic interactions for water wave diffraction on a super large floating structure composed of a large number of box-shaped modules with many small gaps in between. And meanwhile, it also aims to seek for an effective way to take the gap influence into consideration without numerical difficulties existing in conventional methods. An asymptotic matching technique is exploited by virtue of the smallness of gaps. Formal potential solutions are established for the near field around the gap ends and the far field away from gap ends, respectively, and the unknowns in those solutions are uniquely determined by asymptotic matching. The eigen-function expansion method is used for the outer far field and a series of pulsating sources at each gap end is introduced to simulate the gap influence. Strong hydrodynamic interaction is observed and a new resonant phenomenon, the mechanism of which differs absolutely from any known ones, is revealed in the present study. Sharp peak responses for both vertical and horizontal wave-exciting forces on each block are found around some special resonance frequencies, which depend on the draft of the structure and the gap width. The present results are of practical significance to the design of links (connectors) of modules for super large floating structures. And the importance is also closely related to the hydro-elasticity analysis for super large floating structures, in which local loads may be as important as the integrated loads.
文摘Surgery used to be the only therapy for gastric cancer, and since its ability to cure gastric cancer was the focus of attention, less attention was paid to functionpreserving surgery in gastric cancer, though it was studied for gastroduodenal ulcer. Maki et al developed pylorus-preserving gastrectomy for gastric ulcer in 1967. At the same time, the definition of early gastric cancer(EGC) was being considered, histopathological investigations of EGC were carried out, and the validity of modified surgery was sustained. After the development of H2-blockers, the number of operations for gastroduodenal ulcers decreased, and the number of EGC patients increased simultaneously. As a result, the indications for pylorus-preserving gastrectomy for EGC in the middle third of the stomach extended, and various alterations were added. Since then, many kinds of function-preserving gastrectomies have been performed and studied in other fields of gastric cancer, and proximal gastrectomy, jejunal pouch interposition, segmental gastrectomy, and local resection have been performed. On the other hand, from the overall perspective, it can be said that endoscopic resection, which was launched at almost the same time, is the ultimate function-preserving surgery under the current circumstances. The current function-preserving gastrectomies that are often performed and studied are pylorus-preserving gastrectomy and proximal gastrectomy. The reasons for this are that these procedures that can be performed with systemic lymph node dissection, and they include three important elements:(1) reduction of the extent of gastrectomy;(2) preservation of the pylorus; and(3) preservation of the vagal nerve. In addition, these operations are more likely to be performed with a laparoscopic approach as minimally invasive surgery. Of the above-mentioned three elements, reduction of the extent of gastrectomy is the most important in our view. Therefore, we should try to reduce the extent of gastrectomy if curability of the gastric cancer can still be achi
文摘This paper reviews the development of the urban and rural old age security system in China, and discusses the challenges in the process of constructing a sustained old age security system. Althoughfunding gaps and empty individual accounts have imposed a heavy burden on the sustainability of China ＇s urban pension system, there is a relatively high coverage rate of 35.3 percent for urban workers. However, China＇s pension system provides low coverage ratefor rural farmers. The more rapidly aging population and lower incomes in rural areas pose challenges to the vulnerable rural househoM support system. The separation of the oM age security system between rural and urban areas also puts great pressure as a result of urbanization on farmers who lose their farmland. Therefore, it is urgent for China to speed up the reform o fits old age security system to provide an institutional support for its economic and social transition.
基金National Natural Foundation of China.(Grant No.69572015)
文摘This paper presents the optimal design procedure of Tuned Mass Damper (TMD) for reducing vibration of an actual steel jacket offshore platform excited by random wave loading. In this study, a frequency domain is taken. The force on the structure is determined by use of the linearized Morison equation for an input Power Spectral Density (PSD) of wave elevation. The sensitivity of optimum values of TMD to characteristic parameters of random wave spectrum is analyzed. An optimized TMD design for the modeled platform is given based on design conditions and the findings of the study.
基金Project supported through grants from the Swiss National Science Foundationthe WCU program from the National Science Foundation of Korea for grant R31-10035
文摘Present-day advanced technologies heavily rely on the exciting magnetic and spectroscopic properties of lanthanide ions. In particular, their ability to generate well-characterized and intense near-infrared (NIR) luminescence is exploited in any modern fiber-optic telecommunication network. In this feature article, we first summarize the whereabouts underlying the design of highly luminescent NIR molecular edifices and materials. We then focus on describing the main trends in three applications related to this spectral range: telecommunications, biosciences, and solar energy conversion. In telecommunications, efforts concentrate presently on getting easily processable polymer-based waveguide amplifiers. Upconversion nanophosphors emitting in the visible after NIR excitation are now ubiquitous in many bioanalyses while their application to bio-imaging is still in its early stages; however, highly sensitive NIR-NIR systems start to be at hand for both in vitro and in vivo imaging, as well as dual probes combining magnetic resonance and optical imaging. Finally, both silicon-based and dye-sensitized solar cells benefit from the downconversion and upconversion capabilities of lanthanide ions to harvest UV and NIR solar light and to boost the overall quantum efficiency of these next-generation devices.
文摘AIM： To assess the efficacy and safety of Saccharomyces boulardii （S. boulardii） in acute watery diarrhoea and its role in reducing the frequency of episodes of diarrhoea in subsequent two months. METHODS： Children from 2 mo to 12 years of age, with acute diarrhoea were selected according to inclusion criteria and randomised in S. boulardii group （treated with ORS, nutritional support and S. boulardii, 250 mg bid） and in control group （treated with ORS and nutritional support only）. Active treatment phase was 5 d and each child was followed for two months afterwards. Frequency and consistency of stools as well as safety of drug was assessed on every visit. A comparison of two groups was done in terms of number of diarrhoeal episode in subsequent two months. RESULTS： There were fifty patients in each group. Baseline characteristics such as mean age and the average frequency of stools were comparable in S. boulardii and control group at the time of inclusion in the trial. By d 3 it reduced to 2.7 and 4.2 stools per d respectively and by d 6 it reduced to 1.6 （5. boulardii Group） and 3.3 （control group）. The duration of diarrhoea was 3.6 d in S. boulardii group whereas it was 4.8 d in control group （P = 0.001）. In the following two months, S. boulardii group had a significantly lower frequency of 0.54 episodes as compared to 1.08 episodes in control group. The drug was well accepted and tolerated. There were no reports of the side effects during treatment period CONCLUSION： S. boulardii significantly reduces the frequency and duration of acute diarrhoea. The consistency of stool also improves. The drug is well-tolerated.
文摘The wave propagation behavior in an elastic wedge-shaped medium with an arbitrary shaped cylindrical canyon at its vertex has been studied.Numerical computation of the wave displacement field is carried out on and near the canyon surfaces using weighted-residuals(moment method).The wave displacement fields are computed by the residual method for the cases of elliptic,circular,rounded-rectangular and flat-elliptic canyons,The analysis demonstrates that the resulting surface displacement depends,as in similar previous analyses,on several factors including,but not limited,to the angle of the wedge,the geometry of the vertex,the frequencies of the incident waves,the angles of incidence,and the material properties of the media.The analysis provides intriguing results that help to explain geophysical observations regarding the amplification of seismic energy as a function of site conditions.
基金National Natural Science Foundation of China Under Grant No.50378063
文摘Few studies of wave propagation in layered saturated soils have been reported in the literature.In this paper,a general solution of the equation of wave motion in saturated soils,based on one kind of practical Blot's equation, was deduced by introducing wave potentials.Then exact dynamic-stiffness matrices for a poroelastic soil layer and half- space were derived,which extended Wolf's theory for an elastic layered site to the case of poroelasticity,thus resolving a fundamental problem in the field of wave propagation and soil-structure interaction in a poroelastic layered soil site.By using the integral transform method,Green's functions of horizontal and vertical uniformly distributed loads in a poroelastic layered soil site were given.Finally,the theory was verified by numerical examples and dynamic responses by comparing three different soil sites.This study has the following advantages:all parameters in the dynamic-stiffness matrices have explicitly physical meanings and the thickness of the sub-layers does not affect the precision of the calculation which is very convenient for engineering applications.The present theory can degenerate into Wolf's theory and yields numerical results approaching those for an ideal elastic layered site when porosity tends to zero.
文摘 Endoscopic retrograde cholangiopancreatography(ERCP) has a significant complication rate which can be lowered by adopting technical variations of proven beneficial effect and prophylactic maneuvers such as pancreatic stenting during ERCP or periprocedural non-steroidal anti-inflammatory drug administration.However,adoption of these prophylactic maneuvers by endoscopists is not uniform.In this editorial we discuss the beneficial effects of the aforementioned maneuvers.
基金This paper was funded by the National Natural Science Foundation of China(Nos.7170308&71833003 and 71973014).
文摘The emergence of a digital divide or a lack of internet access may hinder urbanization and adversely affect growth.However,fintech development can help to improve the accessibility and affordability of financial services,particularly for sections of the population formerly excluded from such services.Improved access is expected to stimulate the growth essential for promoting urbanization,possibly alleviating the negative impacts of a digital divide and creating a trickle-down effect.This paper is among the first to investigate the effect of fintech development on urbanization,as indicated by labor transfer from agricultural to non-agricultural sectors in China.It is found that:(i)the digital divide hindered,while fintech development contributed to urbanization;(ii)the positive effect of fintech development on urbanization affects individuals both with and without access to the internet,yielding the so-called trickledown ejfect and thus helping to alleviate the negative consequences of a digital divide;and(Hi)regarding transmission mechanisms,fintech development helps to generate additional jobs and raise income in non-agricultural sectors,stimulating urbanization even for those without access to the internet.
