Ultra-wide band-gap nitrides have huge potential in micro-and optoelectronics due to their tunable wide band-gap,high breakdown field and energy density,excellent chemical and thermal stability.However,their applicati...Ultra-wide band-gap nitrides have huge potential in micro-and optoelectronics due to their tunable wide band-gap,high breakdown field and energy density,excellent chemical and thermal stability.However,their application has been severely hindered by the low p-doping efficiency,which is ascribed to the ultrahigh acceptor activation energy originated from the low valance band maximum.Here,a valance band modulation mode is proposed and a quantum engineering doping method is conducted to achieve high-efficient p-type ultra-wide band-gap nitrides,in which GaN quantum-dots are buried in nitride matrix to produce a new band edge and thus to tune the dopant activation energy.By non-equilibrium doping techniques,quantum engineering doped AIGaN:Mg with Al content of 60%is successfully fabricated.The Mg activation energy has been reduced to about 21 meV,and the hole concentration reaches higher than 10^(18)cm^(-3)at room temperature.Also,similar activation energies are obtained in AIGaN with other Al contents such as 50%and 70%;indicating the universality of the quantum engineering doping method.Moreover,deep-ultraviolet light-emission diodes are fabricated and the improved performance further demonstrates the validity and merit of the method.With the quantum material growth techniques developing,this method would be prevalently available and tremendously stimulate the promotion of ultra-wide band-gap semiconductor-based devices.展开更多
Rapid development of solid-state lighting technology requires new materials with highly efficient and stable luminescence,and especially relies on blue light pumped red phosphors for improved light quality.Herein,we d...Rapid development of solid-state lighting technology requires new materials with highly efficient and stable luminescence,and especially relies on blue light pumped red phosphors for improved light quality.Herein,we discovered an unprecedented red-emitting Mg_(2)AI_(4)Si_(5)0_(18):Eu^(2+)composite phosphor(λex=450 nm,λem=620 nm)via the crystallization of MgO-AI_(2)O_(3)-Sio_(2) aluminosilicate glass.Combined experimental measurement and first-principles calculations verify that Eu^(2+)dopants insert at the vacant channel of Mg_(2)AI_(4)Si_(5)0_(18)crystal with six-fold coordination responsible for the peculiar red emission.Importantly,the resulting phosphor exhibits high internal/external quantum efficiency of 94.5/70.6%,and stable emission against thermal quenching,which reaches industry production.The maximum luminous flux and luminous efficiency of the constructed laser driven red emitting device reaches as high as 274 Im and 54lm W^(-1),respectively.The combinations of extraordinary optical properties coupled with economically favorable and innovative preparation method indicate,that the Mg_(2)AI_(4)Si_(5)0_(18):Eu^(2+)composite phosphor will provide a significant step towards the development of high-power solid-state lighting.展开更多
The recently published study by Duan et al introduces a promising method that combines genomic instability and long non-coding RNAs to improve the prognostic evaluation of hepatocellular carcinoma(HCC),a deadly cancer...The recently published study by Duan et al introduces a promising method that combines genomic instability and long non-coding RNAs to improve the prognostic evaluation of hepatocellular carcinoma(HCC),a deadly cancer associated with considerable morbidity and mortality.This editorial aims to analyze the methodology,key findings,and broader implications of the study within the fields of gastroenterology and oncological surgery,highlighting the shift towards precision medicine in the management of HCC.展开更多
Background: Our hypothesis was that only established and persistent injuries and complications after positioning in the Trendelenburg position are reported and detected, despite that patients may have great discomfort...Background: Our hypothesis was that only established and persistent injuries and complications after positioning in the Trendelenburg position are reported and detected, despite that patients may have great discomfort after surgery. Aim: The aim of this study was to explore patient reported discomfort, pain and functional decrease two hours, 24 hours and four weeks after laparoscopic resection of the colon in the prone lithotomy position, as well as factors potentially associated with reported pain. Methods: A longitudinal self-report questionnaire study was conducted at three time-points. Results: A total of 37 patients responded. Findings show that patients mostly reported pain in relation to the surgical area, but also related to other areas that may be linked to positioning. Conclusion: Even though patients reported mild pain, several of the patients still reported this, four weeks postoperatively, as well as some functional decrease. Our findings support the need to focus on preventing positioning injuries.展开更多
In the following article, the “Satisfaction with the Environmental Condition” in the 20 Italian regions between 2004 and 2020 was estimated using ISTAT-BES data. The data were analyzed using the following econometri...In the following article, the “Satisfaction with the Environmental Condition” in the 20 Italian regions between 2004 and 2020 was estimated using ISTAT-BES data. The data were analyzed using the following econometric techniques, namely: Panel Data with Random Effects, Panel Data with Fixed Effects, Dynamic Panel, Pooled OLS, WLS. The results show that satisfaction with the environmental situation is positively associated with the following variables “People with at least high school diploma”, “Satisfaction with leisure time”, “Concern for the deterioration of the landscape” and negatively associated with “Gross disposable income per capita”, “Dissatisfaction with the landscape of the place of life”, “Perception of the risk of crime”. A cluster analysis was then carried out using the unsupervised k-Means algorithm optimized through the Silhouette coefficient and 3 clusters were found. A comparative analysis was then carried out between eight different machine learning algorithms to predict the trend of satisfaction by environmental situation. The analysis showed that the Tree Ensemble Regression algorithm is the best predictor and estimates a reduction of the variable of 0.05%. Subsequently, using augmented data, a further prediction was made with an estimated result equal to -1.93%.展开更多
What is sustainability? Does it only concern the environment or even socio-economic policies? It is only a question of ethics or a redefinition of industrial policy oriented towards the use of renewable energy, it can...What is sustainability? Does it only concern the environment or even socio-economic policies? It is only a question of ethics or a redefinition of industrial policy oriented towards the use of renewable energy, it can bring benefits both atmospheric and social employment. The need for the development of renewable sources can be in tune with the correct management of the territory in consideration of the fact that these sources involve the widespread implementation of small and medium-sized plants. A model of economic development based on renewable sources should respect the peculiarities and characteristics of the territories involved. It should also think of the territory as a “value” to be strengthened and used in a sustainable and integrated way and no longer as a passive platform on which to install plants. Solar thermal and photovoltaic, biomass, geothermal, hydrological, wind power are some of the sources the various countries must constantly invest. This publication is based on these concepts starting from an analysis of the employment data of the OECD “Organisation for Economic Co-operation and Development countries”, comparing them successively with the results of renewable energy productivity. The analysis was performed by analyzing a sample of 22 countries over a period of 20 years, after which the regression curve for the variables with the OLS method was created. This econometric method has allowed us to analyze the impact that renewable technologies have on the parameters of social welfare and in particular on unemployment.展开更多
For most particle-based applications, formulation in the liquid phase is a decisive step, and thus, particle interactions and stability in liquid media are of major importance. The concept of Hansen solubility paramet...For most particle-based applications, formulation in the liquid phase is a decisive step, and thus, particle interactions and stability in liquid media are of major importance. The concept of Hansen solubility parameters (HSP) was initially invented to describe the interactions of (polymer) molecules and their solubility in different liquids and is increasingly being used in particle technology to describe dispersibility. Because dispersions are not thermodynamically stable, the term Hansen dispersibility parameters (HDP) is used instead of HSP (SiiE, Sobisch, Peukert, Lerche,& Segets, 2018). Herein, we extend a previously developed standardized and non-subjective method for determination of Hansen parameters based on analytical centrifugation to the important class of quantum materials. As a technically relevant model system, zinc oxide quantum dots (QDs) were used to transfer our methodology to nanoparticles (NPs) with sizes below lOnm. The results obtained using the standard procedure starting from a dried powder were compared with those obtained through redispersion from the wet sediment produced during the typical washing procedure of QDs, and drying was observed to play an important role. In conclusion, our study reveals the high potential of HDP for quantifying the interfacial properties of NPs as well as their link to dispersibility.展开更多
In the banking system, a context characterized by growing instability and by the speed of evolution of business dynamics, the system of corporate governance plays a key role, both for large banks and for banks with a ...In the banking system, a context characterized by growing instability and by the speed of evolution of business dynamics, the system of corporate governance plays a key role, both for large banks and for banks with a smaller size. The paper aims to investigate the influence of corporate governance of the banks that operate in the cooperative credit system on performance and quality of loans, over the years 2010-2011-2012. In order to achieve this aim, the following research hypotheses have been formulated： There is a statistically significant relationship between the size and the structure of the board and banks Performance operating in the cooperative credit system; there is a statistically significant relationship between the size and structure of the board and the credit quality of banks operating in the cooperative credit system. The analysis is conducted on a sample composed of 48 Italian banks, divided into 24 cooperative banks and 24 popular banks. The sample is made up of banks from all over Italy and very different in terms of dimension. For the sample construction, data relative to governance of banks were collected from the balance sheets in the period from June to August 2014. Financial-economic data were collected from the Financial Statements and from Bankscope database. The methodology of analysis is based on multivariate OLS （ordinary least squares） regression models. The main results refer to the presence of significant relationships between board dimension and the quality of loans and among the number of committees and performance and the quality of loans. The presence of a significant and negative relationship between the board dimension and the ratio of impaired loans to gross loans indicates the possibility that enlargement of board dimension allows a better quality of loans. The presence of a positive relationship between the number of committees and the ratio of impaired loans to gross loans signals the possibility that a greater number of committees can produce a worse quality of loa展开更多
The work investigates the use of trade credit in Italy for reasons of a financial nature. The analysis considers Italian small and medium-sized enterprises （SMEs） and investigates, over the years of 2009-2011： the ...The work investigates the use of trade credit in Italy for reasons of a financial nature. The analysis considers Italian small and medium-sized enterprises （SMEs） and investigates, over the years of 2009-2011： the existence of functional relationships between the incidence of trade receivables and payables and corporate profitability; the existence of interdependencies between trade credit policy and trade debt policy; and the coexistence of interchangeable and complementary conditions between trade debts and bank loans and other sources of funding. To verify the research hypotheses, linear regression models on a yearly basis are used and these models are put under observation over the years of 2009-2011. We can conclude that there are interdependencies between trade credit policy and trade debt policy and that trade credit is a source of flexible way of financing, also available in periods of crisis, which has a positive effect on the profitability of SMEs and can be utilized as a complementary and substitute source of financing to bank loans.展开更多
Despite the initial skepticism and challenges,minimally invasive liver surgery especially laparoscopic liver resections(LLR),has become a first-choice surgical treatment for various liver tumors in many specialized ce...Despite the initial skepticism and challenges,minimally invasive liver surgery especially laparoscopic liver resections(LLR),has become a first-choice surgical treatment for various liver tumors in many specialized centers worldwide(1-3).It is a safe alternative to open surgery thanks to advantages such as reduced blood loss and complication rates,shorter hospital stay,and better quality of life(4-7).However,laparoscopy requires relatively long learning,and complex procedures are limited to high-volume expert centers(8).展开更多
China has recently established a new policy for the energy use of the Arctic region.Even though it is not a part of the Arctic Council,China has started a series of partnerships with public and private entities of cou...China has recently established a new policy for the energy use of the Arctic region.Even though it is not a part of the Arctic Council,China has started a series of partnerships with public and private entities of countries that are geographically and politically members of the Arctic polar Circle.The project has to be carried out within the“Belt and Road Initiative”,by establishing new trade routes between China and the rest of the world.The study aims at assessing the fuel consumption for the Arctic shipping routes and comparing them to the traditional ones,in terms of cost reduction and time efficiency.Moreover,a brief consideration on oil&gas arctic fields has been carried out,in order to understand how the energy policy of China is changing the resource utilization.展开更多
基金the National Natural Science Foundation for Distinguished Young Scholars of China[61725403]National Natural Science Foundation of China[62004196,61922078,61827813,61834008,61922077]+1 种基金Youth Innovation Promotion Association of CAS[Y201945,2017154]Open Project of Suzhou Institute of Nano-Tech and Nano-Bionics,CAS[20YZ10].
文摘Ultra-wide band-gap nitrides have huge potential in micro-and optoelectronics due to their tunable wide band-gap,high breakdown field and energy density,excellent chemical and thermal stability.However,their application has been severely hindered by the low p-doping efficiency,which is ascribed to the ultrahigh acceptor activation energy originated from the low valance band maximum.Here,a valance band modulation mode is proposed and a quantum engineering doping method is conducted to achieve high-efficient p-type ultra-wide band-gap nitrides,in which GaN quantum-dots are buried in nitride matrix to produce a new band edge and thus to tune the dopant activation energy.By non-equilibrium doping techniques,quantum engineering doped AIGaN:Mg with Al content of 60%is successfully fabricated.The Mg activation energy has been reduced to about 21 meV,and the hole concentration reaches higher than 10^(18)cm^(-3)at room temperature.Also,similar activation energies are obtained in AIGaN with other Al contents such as 50%and 70%;indicating the universality of the quantum engineering doping method.Moreover,deep-ultraviolet light-emission diodes are fabricated and the improved performance further demonstrates the validity and merit of the method.With the quantum material growth techniques developing,this method would be prevalently available and tremendously stimulate the promotion of ultra-wide band-gap semiconductor-based devices.
基金the National Natural Science Foundations of China(Grant Nos.51972118,51961145101,51722202 and 11974022)the Guangzhou Science&Technology Project(202007020005)+1 种基金the Fundamental Research Funds for the Central Universities(D2190980)the Local Innovative and Research Teams Project of Guangdong Pearl River Talents Program(2017BT01X137).
文摘Rapid development of solid-state lighting technology requires new materials with highly efficient and stable luminescence,and especially relies on blue light pumped red phosphors for improved light quality.Herein,we discovered an unprecedented red-emitting Mg_(2)AI_(4)Si_(5)0_(18):Eu^(2+)composite phosphor(λex=450 nm,λem=620 nm)via the crystallization of MgO-AI_(2)O_(3)-Sio_(2) aluminosilicate glass.Combined experimental measurement and first-principles calculations verify that Eu^(2+)dopants insert at the vacant channel of Mg_(2)AI_(4)Si_(5)0_(18)crystal with six-fold coordination responsible for the peculiar red emission.Importantly,the resulting phosphor exhibits high internal/external quantum efficiency of 94.5/70.6%,and stable emission against thermal quenching,which reaches industry production.The maximum luminous flux and luminous efficiency of the constructed laser driven red emitting device reaches as high as 274 Im and 54lm W^(-1),respectively.The combinations of extraordinary optical properties coupled with economically favorable and innovative preparation method indicate,that the Mg_(2)AI_(4)Si_(5)0_(18):Eu^(2+)composite phosphor will provide a significant step towards the development of high-power solid-state lighting.
文摘The recently published study by Duan et al introduces a promising method that combines genomic instability and long non-coding RNAs to improve the prognostic evaluation of hepatocellular carcinoma(HCC),a deadly cancer associated with considerable morbidity and mortality.This editorial aims to analyze the methodology,key findings,and broader implications of the study within the fields of gastroenterology and oncological surgery,highlighting the shift towards precision medicine in the management of HCC.
文摘Background: Our hypothesis was that only established and persistent injuries and complications after positioning in the Trendelenburg position are reported and detected, despite that patients may have great discomfort after surgery. Aim: The aim of this study was to explore patient reported discomfort, pain and functional decrease two hours, 24 hours and four weeks after laparoscopic resection of the colon in the prone lithotomy position, as well as factors potentially associated with reported pain. Methods: A longitudinal self-report questionnaire study was conducted at three time-points. Results: A total of 37 patients responded. Findings show that patients mostly reported pain in relation to the surgical area, but also related to other areas that may be linked to positioning. Conclusion: Even though patients reported mild pain, several of the patients still reported this, four weeks postoperatively, as well as some functional decrease. Our findings support the need to focus on preventing positioning injuries.
文摘In the following article, the “Satisfaction with the Environmental Condition” in the 20 Italian regions between 2004 and 2020 was estimated using ISTAT-BES data. The data were analyzed using the following econometric techniques, namely: Panel Data with Random Effects, Panel Data with Fixed Effects, Dynamic Panel, Pooled OLS, WLS. The results show that satisfaction with the environmental situation is positively associated with the following variables “People with at least high school diploma”, “Satisfaction with leisure time”, “Concern for the deterioration of the landscape” and negatively associated with “Gross disposable income per capita”, “Dissatisfaction with the landscape of the place of life”, “Perception of the risk of crime”. A cluster analysis was then carried out using the unsupervised k-Means algorithm optimized through the Silhouette coefficient and 3 clusters were found. A comparative analysis was then carried out between eight different machine learning algorithms to predict the trend of satisfaction by environmental situation. The analysis showed that the Tree Ensemble Regression algorithm is the best predictor and estimates a reduction of the variable of 0.05%. Subsequently, using augmented data, a further prediction was made with an estimated result equal to -1.93%.
文摘What is sustainability? Does it only concern the environment or even socio-economic policies? It is only a question of ethics or a redefinition of industrial policy oriented towards the use of renewable energy, it can bring benefits both atmospheric and social employment. The need for the development of renewable sources can be in tune with the correct management of the territory in consideration of the fact that these sources involve the widespread implementation of small and medium-sized plants. A model of economic development based on renewable sources should respect the peculiarities and characteristics of the territories involved. It should also think of the territory as a “value” to be strengthened and used in a sustainable and integrated way and no longer as a passive platform on which to install plants. Solar thermal and photovoltaic, biomass, geothermal, hydrological, wind power are some of the sources the various countries must constantly invest. This publication is based on these concepts starting from an analysis of the employment data of the OECD “Organisation for Economic Co-operation and Development countries”, comparing them successively with the results of renewable energy productivity. The analysis was performed by analyzing a sample of 22 countries over a period of 20 years, after which the regression curve for the variables with the OLS method was created. This econometric method has allowed us to analyze the impact that renewable technologies have on the parameters of social welfare and in particular on unemployment.
文摘For most particle-based applications, formulation in the liquid phase is a decisive step, and thus, particle interactions and stability in liquid media are of major importance. The concept of Hansen solubility parameters (HSP) was initially invented to describe the interactions of (polymer) molecules and their solubility in different liquids and is increasingly being used in particle technology to describe dispersibility. Because dispersions are not thermodynamically stable, the term Hansen dispersibility parameters (HDP) is used instead of HSP (SiiE, Sobisch, Peukert, Lerche,& Segets, 2018). Herein, we extend a previously developed standardized and non-subjective method for determination of Hansen parameters based on analytical centrifugation to the important class of quantum materials. As a technically relevant model system, zinc oxide quantum dots (QDs) were used to transfer our methodology to nanoparticles (NPs) with sizes below lOnm. The results obtained using the standard procedure starting from a dried powder were compared with those obtained through redispersion from the wet sediment produced during the typical washing procedure of QDs, and drying was observed to play an important role. In conclusion, our study reveals the high potential of HDP for quantifying the interfacial properties of NPs as well as their link to dispersibility.
文摘In the banking system, a context characterized by growing instability and by the speed of evolution of business dynamics, the system of corporate governance plays a key role, both for large banks and for banks with a smaller size. The paper aims to investigate the influence of corporate governance of the banks that operate in the cooperative credit system on performance and quality of loans, over the years 2010-2011-2012. In order to achieve this aim, the following research hypotheses have been formulated： There is a statistically significant relationship between the size and the structure of the board and banks Performance operating in the cooperative credit system; there is a statistically significant relationship between the size and structure of the board and the credit quality of banks operating in the cooperative credit system. The analysis is conducted on a sample composed of 48 Italian banks, divided into 24 cooperative banks and 24 popular banks. The sample is made up of banks from all over Italy and very different in terms of dimension. For the sample construction, data relative to governance of banks were collected from the balance sheets in the period from June to August 2014. Financial-economic data were collected from the Financial Statements and from Bankscope database. The methodology of analysis is based on multivariate OLS （ordinary least squares） regression models. The main results refer to the presence of significant relationships between board dimension and the quality of loans and among the number of committees and performance and the quality of loans. The presence of a significant and negative relationship between the board dimension and the ratio of impaired loans to gross loans indicates the possibility that enlargement of board dimension allows a better quality of loans. The presence of a positive relationship between the number of committees and the ratio of impaired loans to gross loans signals the possibility that a greater number of committees can produce a worse quality of loa
文摘The work investigates the use of trade credit in Italy for reasons of a financial nature. The analysis considers Italian small and medium-sized enterprises （SMEs） and investigates, over the years of 2009-2011： the existence of functional relationships between the incidence of trade receivables and payables and corporate profitability; the existence of interdependencies between trade credit policy and trade debt policy; and the coexistence of interchangeable and complementary conditions between trade debts and bank loans and other sources of funding. To verify the research hypotheses, linear regression models on a yearly basis are used and these models are put under observation over the years of 2009-2011. We can conclude that there are interdependencies between trade credit policy and trade debt policy and that trade credit is a source of flexible way of financing, also available in periods of crisis, which has a positive effect on the profitability of SMEs and can be utilized as a complementary and substitute source of financing to bank loans.
文摘Despite the initial skepticism and challenges,minimally invasive liver surgery especially laparoscopic liver resections(LLR),has become a first-choice surgical treatment for various liver tumors in many specialized centers worldwide(1-3).It is a safe alternative to open surgery thanks to advantages such as reduced blood loss and complication rates,shorter hospital stay,and better quality of life(4-7).However,laparoscopy requires relatively long learning,and complex procedures are limited to high-volume expert centers(8).
文摘China has recently established a new policy for the energy use of the Arctic region.Even though it is not a part of the Arctic Council,China has started a series of partnerships with public and private entities of countries that are geographically and politically members of the Arctic polar Circle.The project has to be carried out within the“Belt and Road Initiative”,by establishing new trade routes between China and the rest of the world.The study aims at assessing the fuel consumption for the Arctic shipping routes and comparing them to the traditional ones,in terms of cost reduction and time efficiency.Moreover,a brief consideration on oil&gas arctic fields has been carried out,in order to understand how the energy policy of China is changing the resource utilization.
