The aging process is an inexorable fact throughout our lives and is considered a major factor in develo ping neurological dysfunctions associated with cognitive,emotional,and motor impairments.Aging-associated neurode...The aging process is an inexorable fact throughout our lives and is considered a major factor in develo ping neurological dysfunctions associated with cognitive,emotional,and motor impairments.Aging-associated neurodegenerative diseases are characterized by the progressive loss of neuronal structure and function.展开更多
Subcortical vascular mild cognitive impairment(svMCI)is a common prodromal stage of vascular dementia.Although mounting evidence has suggested abnormalities in several single brain network metrics,few studies have exp...Subcortical vascular mild cognitive impairment(svMCI)is a common prodromal stage of vascular dementia.Although mounting evidence has suggested abnormalities in several single brain network metrics,few studies have explored the consistency between functional and structural connectivity networks in svMCI.Here,we constructed such networks using resting-state f MRI for functional connectivity and diffusion tensor imaging for structural connectivity in 30 patients with svMCI and 30 normal controls.The functional networks were then parcellated into topological modules,corresponding to several well-defined functional domains.The coupling between the functional and structural networks was finally estimated and compared at the multiscale network level(whole brain and modular level).We found no significant intergroup differences in the functional–structural coupling within the whole brain;however,there was significantly increased functional–structural coupling within the dorsal attention module and decreased functional–structural coupling within the ventral attention module in the svMCI group.In addition,the svMCI patients demonstrated decreased intramodular connectivity strength in the visual,somatomotor,and dorsal attention modules as well as decreased intermodular connectivity strength between several modules in the functional network,mainly linking the visual,somatomotor,dorsal attention,ventral attention,and frontoparietal control modules.There was no significant correlation between the altered module-level functional–structural coupling and cognitive performance in patients with svMCI.These findings demonstrate for the first time that svMCI is reflected in a selective aberrant topological organization in multiscale brain networks and may improve our understanding of the pathophysiological mechanisms underlying svMCI.展开更多
With the improvement of living standards, people are paying more and more attention to health problems. The antibacterial function of fabrics is therefore of great importance. The structural color(photonic crystal), w...With the improvement of living standards, people are paying more and more attention to health problems. The antibacterial function of fabrics is therefore of great importance. The structural color(photonic crystal), which has been widely investigated and applied on fabric dyeing, contains a large number of hollow microstructure and functional groups, and is easy to be modified and functionalized. Therefore, an innovative way of endowing structural color dye on fabrics with antibacterial property was presented in this paper. The latex spheres and zinc pyrrolidone were co-assembled on polydopamine modified fabrics, antibacterial ion zinc pyrrolidone was therefore loaded into the pores of structural color dye, and brilliant antibacterial fabrics were successfully achieved. The existence of zinc pyrrolidone had little influence on the color saturation of brilliant structural color and meanwhile ensured the structural color dye excellent antibacterial effect. The antibacterial reduction rate of the antibacterial fabric reached 99.99%. Owing to the addition of polyurethane(PUA) coating on the surface of structural color, the fabric modified by the antibacterial structural color dye also presented good washing resistance, which showed great application possibility in functional textile and antibacterial fields.展开更多
National parks are useful entities for looking at coordinated efforts to improve the Tibetan Plateau’s function as an ecological safety barrier and the region’s green development.Research on the characteristics of t...National parks are useful entities for looking at coordinated efforts to improve the Tibetan Plateau’s function as an ecological safety barrier and the region’s green development.Research on the characteristics of the function structures of the Tibetan Plateau’s national parks is vital to promoting their systematic and coordinated development.This paper combines the pressure-state-response model,the rank-size rule and a coupling and coordination model to identify and evaluate the functions of national parks on the Tibetan Plateau and to analyze the categories,hierarchy and structures behind those functions.The results indicate the following:(1)The Tibetan Plateau National Park Cluster needs to maintain internal and external relations.Internally it needs to rationally allocate resources between ecological protection,recreation and community development,and externally it needs to promote its role as an ecological security barrier and promote regional green development by rationally ranking and organizing the individual national parks,so as to handle their co-evolution of functions at multiple scales.(2)Ecological protection,recreation and community development are the most prominent functions of the Tibetan Plateau National Park Cluster,but there is scope to develop their scientific research and education functions.The Zipf index shows that their multi-functional level conforms with the rank-size rule,indicating balanced development.Individual national parks need to strengthen their optimal functions according to their characteristic localization.(3)The degree of coupling between the functions of the Tibetan Plateau National Park Cluster is 0.7809,and the degree of coordination is 0.6227,which indicates a very strong coupling and moderate coordination.The coupling strength and degree of coordination between the multiple functions vary greatly among the individual national parks,which reflects their different function structures.There are four function structure types:fully coordinated,optimally developed,moderately developed and moderately underdeveloped.This study contributes to research on evaluating the functions of national park clusters and analyzing their structures,and it serves as a reference on optimizing and sustainably developing the Tibetan Plateau National Park Cluster.展开更多
The learning Bayesian network （BN） structure from data is an NP-hard problem and still one of the most exciting chal- lenges in the machine learning. In this work, a novel algorithm is presented which combines ideas...The learning Bayesian network （BN） structure from data is an NP-hard problem and still one of the most exciting chal- lenges in the machine learning. In this work, a novel algorithm is presented which combines ideas from local learning, constraint- based, and search-and-score techniques in a principled and ef- fective way. It first reconstructs the junction tree of a BN and then performs a K2-scoring greedy search to orientate the local edges in the cliques of junction tree. Theoretical and experimental results show the proposed algorithm is capable of handling networks with a large number of variables. Its comparison with the well-known K2 algorithm is also presented.展开更多
The work functions of the （110） and （10（3） surfaces of LaB6 are determined from ambient pressure to 39.1 GPa. The work function of the （110） surface slowly decreases but that of the （100） surface remains at a...The work functions of the （110） and （10（3） surfaces of LaB6 are determined from ambient pressure to 39.1 GPa. The work function of the （110） surface slowly decreases but that of the （100） surface remains at a relatively constant value. To determine the reason for this difference, the electron density distribution （EDD） is determined from high-pressure single-crystal x-ray diffraction data by the maximum entropy method. The EDD results show that the chemical bond properties in LaB6 play a key role also investigated by single-crystal x-ray diffraction. In observed from ambient pressure to 39.1 GPa. The structural stability of LaB6 under high pressure is this study, no structural or electronic phase transition is展开更多
The first-principles calculations have been performed to determine the effects of Te doping to the structural, electronic, and optical properties of Ga As NWs. The calculated formation energies show that the single Te...The first-principles calculations have been performed to determine the effects of Te doping to the structural, electronic, and optical properties of Ga As NWs. The calculated formation energies show that the single Te energetically prefers to substitute the core Ga（Ef = 0.4111 eV） under As-rich conditions of Ga As nanowires, while on surface, the single Te tends to substitute the surface As site. With increasing the Te concentration, the favorable substitution sites are 2Te–Ga–A and 3Te–Ga–D. Thus, the stability of the structure of the electronic structure and optical properties are discussed.展开更多
The plane wave pseudo-potential method was used to investigate the structural, electronic, and elastic properties of Cd Se_（1-x）Te_x in the zinc blende phase. It is observed that the electronic properties are improv...The plane wave pseudo-potential method was used to investigate the structural, electronic, and elastic properties of Cd Se_（1-x）Te_x in the zinc blende phase. It is observed that the electronic properties are improved considerably by using LDA ＋ U as compared to the LDA approach. The calculated lattice constants and bulk moduli are also comparable to the experimental results. The cohesive energies for pure Cd Se and Cd Te binary and their mixed alloys are calculated. The second-order elastic constants are also calculated by the Lagrangian theory of elasticity. The elastic properties show that the studied material has a ductile nature.展开更多
Starting with introduction of basic concept of optical coherence tomography(OCT) techniques,this paper focuses on a detailed review of ophthalmic OCT instruments and their clinical applications. As one of the most imp...Starting with introduction of basic concept of optical coherence tomography(OCT) techniques,this paper focuses on a detailed review of ophthalmic OCT instruments and their clinical applications. As one of the most important inventions of ophthalmology instruments,OCT has become a standard imaging tool for daily ophthalmic diagnosis. The imaging capability has been significantly improved during the past ~ 30 years. In this article,several representing systems which have made significant contributions to OCT developments will be reviewed in details. For each system,the system configuration will be discussed first,follow ed by a brief introduction of their clinical applications. The review concludes with discussions on potential directions of OCT developments and expectations for further improvements of OCT imaging capabilities.展开更多
Hydrogel scaffolds have numerous potential applications in the tissue engineering field.However,tough hydrogel scaffolds implanted in vivo are seldom reported because it is difficult to balance biocompatibility and hi...Hydrogel scaffolds have numerous potential applications in the tissue engineering field.However,tough hydrogel scaffolds implanted in vivo are seldom reported because it is difficult to balance biocompatibility and high mechanical properties.Inspired by Chinese ramen,we propose a universal fabricating method(printing-P,training-T,cross-linking-C,PTC&PCT)for tough hydrogel scaffolds to fill this gap.First,3D printing fabricates a hydrogel scaffold with desired structures(P).Then,the scaffold could have extraordinarily high mechanical properties and functional surface structure by cycle mechanical training with salting-out assistance(T).Finally,the training results are fixed by photo-cross-linking processing(C).The tough gelatin hydrogel scaffolds exhibit excellent tensile strength of 6.66 MPa(622-fold untreated)and have excellent biocompatibility.Furthermore,this scaffold possesses functional surface structures from nanometer to micron to millimeter,which can efficiently induce directional cell growth.Interestingly,this strategy can produce bionic human tissue with mechanical properties of 10 kPa-10 MPa by changing the type of salt,and many hydrogels,such as gelatin and silk,could be improved with PTC or PCT strategies.Animal experiments show that this scaffold can effectively promote the new generation of muscle fibers,blood vessels,and nerves within 4 weeks,prompting the rapid regeneration of large-volume muscle loss injuries.展开更多
Hypoxic pulmonary hypertension(HPH)is a pathophysiological state characterized by diverse clinical symptoms resulting from structural and functional changes in pulmonary vessels induced by hypoxic stimuli,leading to i...Hypoxic pulmonary hypertension(HPH)is a pathophysiological state characterized by diverse clinical symptoms resulting from structural and functional changes in pulmonary vessels induced by hypoxic stimuli,leading to increased pulmonary artery pressure.展开更多
Mimicking the electric microenvironment of natural tissue is a promising strategy for developing biomedical implants. However, current research has not taken biomimetic electrical functional units into consideration w...Mimicking the electric microenvironment of natural tissue is a promising strategy for developing biomedical implants. However, current research has not taken biomimetic electrical functional units into consideration when designing biomedical implants. In this research, ordered structures with Schottky heterojunction functional unit (OSSH) were constructed on titanium implant surfaces for bone regeneration regulation. The Schottky heterojunction functional unit is composed of periodically distributed titanium microdomain and titanium oxide microdomain with different carrier densities and surface potentials. The OSSH regulates the M2-type polarization of macrophages to a regenerative immune response by activating the PI3K-AKT-mTOR signal pathway and further promotes osteogenic differentiation of rat bone marrow mesenchymal stem cells. This work provides fundamental insights into the biological effects driven by the Schottky heterojunction functional units that can electrically modulate osteogenesis.展开更多
Neuron glia antigen-2(NG2)glia,also known as oligodendrocyte precursor cells(OPCs),are essential for maintaining the normal function and structure of the central nervous system(CNS)due to their supportive role[1].Unde...Neuron glia antigen-2(NG2)glia,also known as oligodendrocyte precursor cells(OPCs),are essential for maintaining the normal function and structure of the central nervous system(CNS)due to their supportive role[1].Under physiological conditions,NG2 glia are involved in myelination by differentiating into oligodendrocytes,which are responsible for forming the myelin sheath around axons[2].In addition,the NG2 glia can directly influence the activity of neuronal circuits by receiving synaptic input from neurons and generating action potentials[3].Under pathological conditions,such as in response to injury or disease,the NG2 glia proliferate and differentiate to replace damaged oligodendrocytes,contributing to the repair and regeneration of myelin[4].展开更多
As the most important type or component in the terrestrial ecosystems, forest ecosystem makes its role obviously prominent and important on environment and human being. It possesses non-substitutable functions in the ...As the most important type or component in the terrestrial ecosystems, forest ecosystem makes its role obviously prominent and important on environment and human being. It possesses non-substitutable functions in the process of sustainable development. However, due to the complexity of the forest ecosystem and the relatively delay or lack of the related research technology, the science is still in the case of immature and questions. This paper summarized and reviewed briefly the development and the present case of the forest ecology, then pointed out the existing problems in the forest ecosystem researches. In the end, we discussed several fields that need to pay more attention to in future researches.展开更多
Irritable bowel syndrome(IBS)is a common clinical label for medically unexplained gastrointestinal symptoms,recently described as a disturbance of the microbiota-gut-brain axis.Despite decades of research,the pathophy...Irritable bowel syndrome(IBS)is a common clinical label for medically unexplained gastrointestinal symptoms,recently described as a disturbance of the microbiota-gut-brain axis.Despite decades of research,the pathophysiology of this highly heterogeneous disorder remains elusive.However,a dramatic change in the understanding of the underlying pathophysiological mechanisms surfaced when the importance of gut microbiota protruded the scientific picture.Are we getting any closer to understanding IBS’etiology,or are we drowning in unspecific,conflicting data because we possess limited tools to unravel the cluster of secrets our gut microbiota is concealing?In this comprehensive review we are discussing some of the major important features of IBS and their interaction with gut microbiota,clinical microbiota-altering treatment such as the low FODMAP diet and fecal microbiota transplantation,neuroimaging and methods in microbiota analyses,and current and future challenges with big data analysis in IBS.展开更多
Based on S-rough sets（singular rough sets）, this paper presents function S-rough sets （function singular rough sets）and its mathematical structures and features. Function S-rough sets has two forms： function one ...Based on S-rough sets（singular rough sets）, this paper presents function S-rough sets （function singular rough sets）and its mathematical structures and features. Function S-rough sets has two forms： function one direction S-rough sets （function one direction singular rough sets） and function two direction S-rough sets （function two direction singular rough sets）. This paper advances the relationship theorem of function S-rough sets and S-rough sets. Function S-rough sets is the general form of S-rough sets, and S-rough sets is the special ease of function S-rough sets. In this paper, applications of function S-rough sets in rough law mining-discovery of system are given. Function S-rough sets is a new research direction of rough sets and rough system.展开更多
Function S-rough sets （function singular rough sets） is defined on a -function equivalence class [u]. Function S-rough sets is the extension form of S-rough sets. By using the function S-rough sets, this paper gives...Function S-rough sets （function singular rough sets） is defined on a -function equivalence class [u]. Function S-rough sets is the extension form of S-rough sets. By using the function S-rough sets, this paper gives rough law generation model of a-function equivalence class, discussion on law mining and law discovery in systems, and application of law mining and law discovery in communication system. Function S-rough sets is a new theory and method in law mining research.展开更多
The evaluation of thermal resistance constitution for packaged A1GaN/GaN high electron mobility transistor （HEMT） by structure function method is proposed in this paper. The evaluation is based on the transient heat...The evaluation of thermal resistance constitution for packaged A1GaN/GaN high electron mobility transistor （HEMT） by structure function method is proposed in this paper. The evaluation is based on the transient heating measurement of the A1GaN/GaN HEMT by pulsed electrical temperature sensitive parameter method. The extracted chip-level and package-level thermal resistances of the packaged multi-finger A1GaN/GaN HEMT with 400μm SiC substrate are 22.5 K/W and 7.2 K/W respectively, which provides a non-invasive method to evaluate the chip-level thermal resistance of packaged A1GaN/GaN HEMTs. It is also experimentally proved that the extraction of the chip- level thermal resistance by this proposed method is not influenced by package form of the tested device and temperature boundary condition of measurement stage.展开更多
Marine geographic information system （MGIS） has great ability to deal with the spatio-temporal problems and has potential superiority when it is applied to oceanography. Using the feature extraction of oceanic pheno...Marine geographic information system （MGIS） has great ability to deal with the spatio-temporal problems and has potential superiority when it is applied to oceanography. Using the feature extraction of oceanic phenomena as a case study, the functions of the MGIS are analyzed, and thus the position of MGIS in the oceanography is defined. Comparing the requirement of MGIS with that of the traditional GIS which has been developed in the terrestrial applications in the past four decades, the frame for the functions of MGIS is constructed. According to the established MGIS, some key technologies are discussed in detail with emphasis on the specialities which can distinguish the MGIS from the traditional GIS.展开更多
Cuticular wax plays a major role in the growth and storage of plant fruits.The cuticular wax coating,which covers the outermost layer of a fruit’s epidermal cells,is insoluble in water.Cuticular wax is mainly compose...Cuticular wax plays a major role in the growth and storage of plant fruits.The cuticular wax coating,which covers the outermost layer of a fruit’s epidermal cells,is insoluble in water.Cuticular wax is mainly composed of very long-chain fatty acids(VLCFAs);their derivatives,including esters,primary alcohols,secondary alcohols,aldehydes,and ketones;and triterpenoids.This complex mixture of lipids is probably biosynthesized in the epidermal cells of most plants and exuded onto the surface.Cuticular wax not only makes the fruit less susceptible to microbial infection but also reduces mechanical damage to the fruit,thereby maintaining the fruit’s commodity value.To date,research has mostly focused on the changes,function,and regulation of fruit wax before harvest,while ignoring the changes and functions of wax in fruit storage.This paper reviews on the composition,structure,and metabolic regulation of cuticular wax in fruits.It also focuses on postharvest factors affecting wax composition,such as storage temperature,relative humidity(RH),gas atmosphere,and as exogenous hormones;and the effects of wax on fruit postharvest quality,including water dispersion,fruit softening,physiological disorders,and disease resistance.These summaries may be of assistance in better understanding the changes in cuticular wax in postharvest fruit and the resulting effects on fruit quality.展开更多
文摘The aging process is an inexorable fact throughout our lives and is considered a major factor in develo ping neurological dysfunctions associated with cognitive,emotional,and motor impairments.Aging-associated neurodegenerative diseases are characterized by the progressive loss of neuronal structure and function.
基金supported by the Natural Science Foundation of Tianjin Municipal Science and Technology Commission(18JCQNJC10900)Tianjin Natural Science Foundation(17JCZDJC36300)。
文摘Subcortical vascular mild cognitive impairment(svMCI)is a common prodromal stage of vascular dementia.Although mounting evidence has suggested abnormalities in several single brain network metrics,few studies have explored the consistency between functional and structural connectivity networks in svMCI.Here,we constructed such networks using resting-state f MRI for functional connectivity and diffusion tensor imaging for structural connectivity in 30 patients with svMCI and 30 normal controls.The functional networks were then parcellated into topological modules,corresponding to several well-defined functional domains.The coupling between the functional and structural networks was finally estimated and compared at the multiscale network level(whole brain and modular level).We found no significant intergroup differences in the functional–structural coupling within the whole brain;however,there was significantly increased functional–structural coupling within the dorsal attention module and decreased functional–structural coupling within the ventral attention module in the svMCI group.In addition,the svMCI patients demonstrated decreased intramodular connectivity strength in the visual,somatomotor,and dorsal attention modules as well as decreased intermodular connectivity strength between several modules in the functional network,mainly linking the visual,somatomotor,dorsal attention,ventral attention,and frontoparietal control modules.There was no significant correlation between the altered module-level functional–structural coupling and cognitive performance in patients with svMCI.These findings demonstrate for the first time that svMCI is reflected in a selective aberrant topological organization in multiscale brain networks and may improve our understanding of the pathophysiological mechanisms underlying svMCI.
基金National Nature Science Foundation of China(No.51503034)Science and Technology Commission of Shanghai Municipality for Yangfan Program,China(No.15YF1400700)。
文摘With the improvement of living standards, people are paying more and more attention to health problems. The antibacterial function of fabrics is therefore of great importance. The structural color(photonic crystal), which has been widely investigated and applied on fabric dyeing, contains a large number of hollow microstructure and functional groups, and is easy to be modified and functionalized. Therefore, an innovative way of endowing structural color dye on fabrics with antibacterial property was presented in this paper. The latex spheres and zinc pyrrolidone were co-assembled on polydopamine modified fabrics, antibacterial ion zinc pyrrolidone was therefore loaded into the pores of structural color dye, and brilliant antibacterial fabrics were successfully achieved. The existence of zinc pyrrolidone had little influence on the color saturation of brilliant structural color and meanwhile ensured the structural color dye excellent antibacterial effect. The antibacterial reduction rate of the antibacterial fabric reached 99.99%. Owing to the addition of polyurethane(PUA) coating on the surface of structural color, the fabric modified by the antibacterial structural color dye also presented good washing resistance, which showed great application possibility in functional textile and antibacterial fields.
基金The Second Tibetan Plateau Scientific Expedition and Research Program,No.2019QZKK0401Strategic Priority Research Program of the Chinese Academy of Sciences,No.XDA20020302。
文摘National parks are useful entities for looking at coordinated efforts to improve the Tibetan Plateau’s function as an ecological safety barrier and the region’s green development.Research on the characteristics of the function structures of the Tibetan Plateau’s national parks is vital to promoting their systematic and coordinated development.This paper combines the pressure-state-response model,the rank-size rule and a coupling and coordination model to identify and evaluate the functions of national parks on the Tibetan Plateau and to analyze the categories,hierarchy and structures behind those functions.The results indicate the following:(1)The Tibetan Plateau National Park Cluster needs to maintain internal and external relations.Internally it needs to rationally allocate resources between ecological protection,recreation and community development,and externally it needs to promote its role as an ecological security barrier and promote regional green development by rationally ranking and organizing the individual national parks,so as to handle their co-evolution of functions at multiple scales.(2)Ecological protection,recreation and community development are the most prominent functions of the Tibetan Plateau National Park Cluster,but there is scope to develop their scientific research and education functions.The Zipf index shows that their multi-functional level conforms with the rank-size rule,indicating balanced development.Individual national parks need to strengthen their optimal functions according to their characteristic localization.(3)The degree of coupling between the functions of the Tibetan Plateau National Park Cluster is 0.7809,and the degree of coordination is 0.6227,which indicates a very strong coupling and moderate coordination.The coupling strength and degree of coordination between the multiple functions vary greatly among the individual national parks,which reflects their different function structures.There are four function structure types:fully coordinated,optimally developed,moderately developed and moderately underdeveloped.This study contributes to research on evaluating the functions of national park clusters and analyzing their structures,and it serves as a reference on optimizing and sustainably developing the Tibetan Plateau National Park Cluster.
基金supported by the National Natural Science Fundation of China (6097408261075055)the Fundamental Research Funds for the Central Universities (K50510700004)
文摘The learning Bayesian network （BN） structure from data is an NP-hard problem and still one of the most exciting chal- lenges in the machine learning. In this work, a novel algorithm is presented which combines ideas from local learning, constraint- based, and search-and-score techniques in a principled and ef- fective way. It first reconstructs the junction tree of a BN and then performs a K2-scoring greedy search to orientate the local edges in the cliques of junction tree. Theoretical and experimental results show the proposed algorithm is capable of handling networks with a large number of variables. Its comparison with the well-known K2 algorithm is also presented.
基金Supported by the National Natural Science Foundation of China under Grant Nos 11274030 and 11474281
文摘The work functions of the （110） and （10（3） surfaces of LaB6 are determined from ambient pressure to 39.1 GPa. The work function of the （110） surface slowly decreases but that of the （100） surface remains at a relatively constant value. To determine the reason for this difference, the electron density distribution （EDD） is determined from high-pressure single-crystal x-ray diffraction data by the maximum entropy method. The EDD results show that the chemical bond properties in LaB6 play a key role also investigated by single-crystal x-ray diffraction. In observed from ambient pressure to 39.1 GPa. The structural stability of LaB6 under high pressure is this study, no structural or electronic phase transition is
基金supported by the Open Fund of State Key Laboratory of Information Photonics and Optical Communications(Beijing University of Posts and Telecommunications,China,No.2012LF1003)the Research Foundation of Education Bureau of Sichuan Province(No.16ZA0316)
文摘The first-principles calculations have been performed to determine the effects of Te doping to the structural, electronic, and optical properties of Ga As NWs. The calculated formation energies show that the single Te energetically prefers to substitute the core Ga（Ef = 0.4111 eV） under As-rich conditions of Ga As nanowires, while on surface, the single Te tends to substitute the surface As site. With increasing the Te concentration, the favorable substitution sites are 2Te–Ga–A and 3Te–Ga–D. Thus, the stability of the structure of the electronic structure and optical properties are discussed.
文摘The plane wave pseudo-potential method was used to investigate the structural, electronic, and elastic properties of Cd Se_（1-x）Te_x in the zinc blende phase. It is observed that the electronic properties are improved considerably by using LDA ＋ U as compared to the LDA approach. The calculated lattice constants and bulk moduli are also comparable to the experimental results. The cohesive energies for pure Cd Se and Cd Te binary and their mixed alloys are calculated. The second-order elastic constants are also calculated by the Lagrangian theory of elasticity. The elastic properties show that the studied material has a ductile nature.
文摘Starting with introduction of basic concept of optical coherence tomography(OCT) techniques,this paper focuses on a detailed review of ophthalmic OCT instruments and their clinical applications. As one of the most important inventions of ophthalmology instruments,OCT has become a standard imaging tool for daily ophthalmic diagnosis. The imaging capability has been significantly improved during the past ~ 30 years. In this article,several representing systems which have made significant contributions to OCT developments will be reviewed in details. For each system,the system configuration will be discussed first,follow ed by a brief introduction of their clinical applications. The review concludes with discussions on potential directions of OCT developments and expectations for further improvements of OCT imaging capabilities.
基金supported by the Innovative Research Group Project of the National Natural Science Foundation of China(T2121004)Key Programme(52235007)National Outstanding Youth Foundation of China(52325504).
文摘Hydrogel scaffolds have numerous potential applications in the tissue engineering field.However,tough hydrogel scaffolds implanted in vivo are seldom reported because it is difficult to balance biocompatibility and high mechanical properties.Inspired by Chinese ramen,we propose a universal fabricating method(printing-P,training-T,cross-linking-C,PTC&PCT)for tough hydrogel scaffolds to fill this gap.First,3D printing fabricates a hydrogel scaffold with desired structures(P).Then,the scaffold could have extraordinarily high mechanical properties and functional surface structure by cycle mechanical training with salting-out assistance(T).Finally,the training results are fixed by photo-cross-linking processing(C).The tough gelatin hydrogel scaffolds exhibit excellent tensile strength of 6.66 MPa(622-fold untreated)and have excellent biocompatibility.Furthermore,this scaffold possesses functional surface structures from nanometer to micron to millimeter,which can efficiently induce directional cell growth.Interestingly,this strategy can produce bionic human tissue with mechanical properties of 10 kPa-10 MPa by changing the type of salt,and many hydrogels,such as gelatin and silk,could be improved with PTC or PCT strategies.Animal experiments show that this scaffold can effectively promote the new generation of muscle fibers,blood vessels,and nerves within 4 weeks,prompting the rapid regeneration of large-volume muscle loss injuries.
基金supported by General Program of the Natural Science Foundation of Hebei Province(No.H2024110033,China).
文摘Hypoxic pulmonary hypertension(HPH)is a pathophysiological state characterized by diverse clinical symptoms resulting from structural and functional changes in pulmonary vessels induced by hypoxic stimuli,leading to increased pulmonary artery pressure.
基金supported by the National Natural Science Foundation of China(Nos.52072127,52201297,U21A2055,and U22A20160)the China Postdoctoral Science Foundation(No.2022M711200)the Royal Society(No.IEC/NSFC/191344)(UK).
文摘Mimicking the electric microenvironment of natural tissue is a promising strategy for developing biomedical implants. However, current research has not taken biomimetic electrical functional units into consideration when designing biomedical implants. In this research, ordered structures with Schottky heterojunction functional unit (OSSH) were constructed on titanium implant surfaces for bone regeneration regulation. The Schottky heterojunction functional unit is composed of periodically distributed titanium microdomain and titanium oxide microdomain with different carrier densities and surface potentials. The OSSH regulates the M2-type polarization of macrophages to a regenerative immune response by activating the PI3K-AKT-mTOR signal pathway and further promotes osteogenic differentiation of rat bone marrow mesenchymal stem cells. This work provides fundamental insights into the biological effects driven by the Schottky heterojunction functional units that can electrically modulate osteogenesis.
基金supported by the National Natural Science Foundation of China(32300959)a Guangzhou Scientific Research Grant(SL2024A04J00578)the SCNU Young Faculty Development Program(22KJ04).
文摘Neuron glia antigen-2(NG2)glia,also known as oligodendrocyte precursor cells(OPCs),are essential for maintaining the normal function and structure of the central nervous system(CNS)due to their supportive role[1].Under physiological conditions,NG2 glia are involved in myelination by differentiating into oligodendrocytes,which are responsible for forming the myelin sheath around axons[2].In addition,the NG2 glia can directly influence the activity of neuronal circuits by receiving synaptic input from neurons and generating action potentials[3].Under pathological conditions,such as in response to injury or disease,the NG2 glia proliferate and differentiate to replace damaged oligodendrocytes,contributing to the repair and regeneration of myelin[4].
基金This study was supported by the National Natural Science Foundation of China (NSFC39970123 30170744)+1 种基金 Chinese Academy of Sciences (A grant KZCX2-406) and Changbai Mountain Open Research Station.
文摘As the most important type or component in the terrestrial ecosystems, forest ecosystem makes its role obviously prominent and important on environment and human being. It possesses non-substitutable functions in the process of sustainable development. However, due to the complexity of the forest ecosystem and the relatively delay or lack of the related research technology, the science is still in the case of immature and questions. This paper summarized and reviewed briefly the development and the present case of the forest ecology, then pointed out the existing problems in the forest ecosystem researches. In the end, we discussed several fields that need to pay more attention to in future researches.
基金Supported by the Spanish Ministry of Science and Innovation(MICINN,Spain),No.AGL2017-88801-P(to Sanz Y)the Miguel Server grant from the Spanish"Carlos III"Health Institute(ISCIII),No.CP19/00132(to Benitez-Paez A)+2 种基金The Norwegian Research Council(Funding Postdoc Position for Bharath Halandur Nagaraja),No.FRIMEDBIO276010and Helse Vest’s Research Funding,No.HV912243and ERC H2020-MSCA-IF-2019,No.895219(to Haleem N).
文摘Irritable bowel syndrome(IBS)is a common clinical label for medically unexplained gastrointestinal symptoms,recently described as a disturbance of the microbiota-gut-brain axis.Despite decades of research,the pathophysiology of this highly heterogeneous disorder remains elusive.However,a dramatic change in the understanding of the underlying pathophysiological mechanisms surfaced when the importance of gut microbiota protruded the scientific picture.Are we getting any closer to understanding IBS’etiology,or are we drowning in unspecific,conflicting data because we possess limited tools to unravel the cluster of secrets our gut microbiota is concealing?In this comprehensive review we are discussing some of the major important features of IBS and their interaction with gut microbiota,clinical microbiota-altering treatment such as the low FODMAP diet and fecal microbiota transplantation,neuroimaging and methods in microbiota analyses,and current and future challenges with big data analysis in IBS.
基金This project was surpported by the Natural Science Foundation of Shandong Province of China (Y2004A94)
文摘Based on S-rough sets（singular rough sets）, this paper presents function S-rough sets （function singular rough sets）and its mathematical structures and features. Function S-rough sets has two forms： function one direction S-rough sets （function one direction singular rough sets） and function two direction S-rough sets （function two direction singular rough sets）. This paper advances the relationship theorem of function S-rough sets and S-rough sets. Function S-rough sets is the general form of S-rough sets, and S-rough sets is the special ease of function S-rough sets. In this paper, applications of function S-rough sets in rough law mining-discovery of system are given. Function S-rough sets is a new research direction of rough sets and rough system.
基金This project was supported by Natural Science Foundation of Shandong Province of China (Y2004A04), Natural ScienceFoundation of Fujian of China (Z051049) and Education Foundation of Fujian of China (JA04268),.
文摘Function S-rough sets （function singular rough sets） is defined on a -function equivalence class [u]. Function S-rough sets is the extension form of S-rough sets. By using the function S-rough sets, this paper gives rough law generation model of a-function equivalence class, discussion on law mining and law discovery in systems, and application of law mining and law discovery in communication system. Function S-rough sets is a new theory and method in law mining research.
基金supported by the Natural Science Foundation of Beijing,China (Grant No. 4092005)the National High Technology Research and Development Program of China (Grant No. 2009AA032704)the Specialized Research Fund for the Doctoral Program of Higher Education of China (Grant No. 20091103110006)
文摘The evaluation of thermal resistance constitution for packaged A1GaN/GaN high electron mobility transistor （HEMT） by structure function method is proposed in this paper. The evaluation is based on the transient heating measurement of the A1GaN/GaN HEMT by pulsed electrical temperature sensitive parameter method. The extracted chip-level and package-level thermal resistances of the packaged multi-finger A1GaN/GaN HEMT with 400μm SiC substrate are 22.5 K/W and 7.2 K/W respectively, which provides a non-invasive method to evaluate the chip-level thermal resistance of packaged A1GaN/GaN HEMTs. It is also experimentally proved that the extraction of the chip- level thermal resistance by this proposed method is not influenced by package form of the tested device and temperature boundary condition of measurement stage.
基金funded by the Project of"973"Program of China under contract No.2006 CB701305the National Natural Science Foundation of China under contract No.40571129.
文摘Marine geographic information system （MGIS） has great ability to deal with the spatio-temporal problems and has potential superiority when it is applied to oceanography. Using the feature extraction of oceanic phenomena as a case study, the functions of the MGIS are analyzed, and thus the position of MGIS in the oceanography is defined. Comparing the requirement of MGIS with that of the traditional GIS which has been developed in the terrestrial applications in the past four decades, the frame for the functions of MGIS is constructed. According to the established MGIS, some key technologies are discussed in detail with emphasis on the specialities which can distinguish the MGIS from the traditional GIS.
基金This work was supported by the National Natural Science Foundation of China(31772042)Ramóny Cajal grant(RYC2020-030365-I)+1 种基金Xunta de Galicia for supporting the program(Excelencia-ED431F2022/01)the Key Research&Development Program of Zhejiang Province(2021C02015).
文摘Cuticular wax plays a major role in the growth and storage of plant fruits.The cuticular wax coating,which covers the outermost layer of a fruit’s epidermal cells,is insoluble in water.Cuticular wax is mainly composed of very long-chain fatty acids(VLCFAs);their derivatives,including esters,primary alcohols,secondary alcohols,aldehydes,and ketones;and triterpenoids.This complex mixture of lipids is probably biosynthesized in the epidermal cells of most plants and exuded onto the surface.Cuticular wax not only makes the fruit less susceptible to microbial infection but also reduces mechanical damage to the fruit,thereby maintaining the fruit’s commodity value.To date,research has mostly focused on the changes,function,and regulation of fruit wax before harvest,while ignoring the changes and functions of wax in fruit storage.This paper reviews on the composition,structure,and metabolic regulation of cuticular wax in fruits.It also focuses on postharvest factors affecting wax composition,such as storage temperature,relative humidity(RH),gas atmosphere,and as exogenous hormones;and the effects of wax on fruit postharvest quality,including water dispersion,fruit softening,physiological disorders,and disease resistance.These summaries may be of assistance in better understanding the changes in cuticular wax in postharvest fruit and the resulting effects on fruit quality.
