DEAR EDITOR,We identified strict monandry in a wandering wolf spider species(Pardosa pseudoannulata) and revealed the underlying mechanisms of this mating structure. Evidence indicated that males damaged the inner wal...DEAR EDITOR,We identified strict monandry in a wandering wolf spider species(Pardosa pseudoannulata) and revealed the underlying mechanisms of this mating structure. Evidence indicated that males damaged the inner walls of the female genital tract with the sharp part of their intromittent organ during insemination. The traumatic mating caused hemolymph hemorrhage, which mixed with seminal fluid and gradually formed an impermeable amorphous mating plug after about15 days, completely blocking the female copulatory opening.展开更多
Endoscopic mucosal resection(EMR) and endoscopic submucosal dissection(ESD) have recently been accepted as less invasive methods for treating patients with early esophageal cancers such as squamous cell carcinoma and ...Endoscopic mucosal resection(EMR) and endoscopic submucosal dissection(ESD) have recently been accepted as less invasive methods for treating patients with early esophageal cancers such as squamous cell carcinoma and dysplasia of Barrett's esophagus.However,the large defects in the esophageal mucosa often cause severe esophageal strictures,which dramatically reduce the patient's quality of life.Although preventive endoscopic balloon dilatation can reduce dysphagia and the frequency of dilatation,other approaches are necessary to prevent esophageal strictures after ESD.This review describes several strategies for preventing esophageal strictures after ESD,with a particular focus on anti-inflammatory and tissue engineering approaches.The local injection of triamcinolone acetonide and other systemic steroid therapies are frequently used to prevent esophageal strictures after ESD.Tissue engineering approaches for preventing esophageal strictures have recently been applied in basic research studies.Scaffolds with temporary stents have been applied in five cases,and this technique has been shown to be safe and is anticipated to prevent esophageal strictures.Fabricated autologous oral mucosal epithelial cell sheets to cover the defective mucosa similarly to how commercially available skin products fabricated from epidermal cells are used for skin defects or in cases of intractable ulcers.Fabricated autologous oralmucosal-epithelial cell sheets have already been shown to be safe.展开更多
In this paper we use the notion of measure of non-strict-singularity to give some results on Fredholm operators and we establish a fine description of the Schechter essential spectrum of a closed densely defined linea...In this paper we use the notion of measure of non-strict-singularity to give some results on Fredholm operators and we establish a fine description of the Schechter essential spectrum of a closed densely defined linear operator.展开更多
Generalized strictly diagonally dominant matrices play a wide and important role in computational mathematics, mathematical physics, theory of dynamical systems, etc.But it is difficult to judge a matrix is or not gen...Generalized strictly diagonally dominant matrices play a wide and important role in computational mathematics, mathematical physics, theory of dynamical systems, etc.But it is difficult to judge a matrix is or not generalized strictly diagonally dominant matrix.In this paper, by using the properties of α-chain diagonally dominant matrix, we obtain new criteria for judging generalized strictly diagonally dominant matrix, which enlarge the identification range.展开更多
A generalized Lyness equation is investigated as follows x n+1 =x n(a+bx n )x n-1 , n=0,1,2,…,(*) where a,b∈[0,∞) with a+b>0 and where the initial values x -1 ,x 0 are arbitrary positive numbers. Som...A generalized Lyness equation is investigated as follows x n+1 =x n(a+bx n )x n-1 , n=0,1,2,…,(*) where a,b∈[0,∞) with a+b>0 and where the initial values x -1 ,x 0 are arbitrary positive numbers. Some new results, mainly a necessary and sufficient condition for the periodicity of the solutions of Eq.(*) and a sufficient condition for the strict oscillation of all solutions of Eq(*),are obtained. As an application, the results solve an open problem presented by G.Ladas.展开更多
In this paper,we introduce a general hybrid iterative method to find an infinite family of strict pseudo-contractions in a q-uniformly smooth and strictly convex Banach space.Moreover,we show that the sequence defined...In this paper,we introduce a general hybrid iterative method to find an infinite family of strict pseudo-contractions in a q-uniformly smooth and strictly convex Banach space.Moreover,we show that the sequence defined by the iterative method converges strongly to a common element of the set of fixed points,which is the unique solution of the variational inequality<(λφ−νF)z,jq(z−z)>≤0,for z∈⋂_(i=1)^(∞)Γ(S_(i)).The results introduced in our work extend to some corresponding theorems.展开更多
What lurks within the crypt?With more than 200 known causes of is chemic stroke(Saver,2016),what should be the minimum work up?Many centers offer high-resolution brain imaging and vessel studies,telemetry monitoring f...What lurks within the crypt?With more than 200 known causes of is chemic stroke(Saver,2016),what should be the minimum work up?Many centers offer high-resolution brain imaging and vessel studies,telemetry monitoring for atrial fibrillation(AF),trans-thoracic and transesophageal echocardiography.展开更多
Kogyae Strict Nature Reserve, the only one in Ghana, was established to promote scientific research, particularly on how nature revitalizes itself after major disasters, and also to check the southward drift of the sa...Kogyae Strict Nature Reserve, the only one in Ghana, was established to promote scientific research, particularly on how nature revitalizes itself after major disasters, and also to check the southward drift of the savannah grassland. This study presents the first comprehensive inventory of species composition and diversity of insects of the Reserve. Insects were surveyed between September 2011 and June 2012 to capture the end of the rainy season, the dry season and the peak of the wet season. Samples were taken from two sites within the Reserve, Dagomba and Oku using various sampling techniques including pitfall traps, malaise traps and sweep nets. Insect communities were characterized in terms of, 1) species richness estimators, 2) species richness, 3) Shannon-Weiner Index of Diversity, 4) Pielou’s evenness and 5) Bray-Curtis similarity. A total of 8147 individuals representing 135 families from 21 orders were recorded. This included 107 species of butterflies from 9 families and 20 species of dragonflies from 3 families. Oku recorded the highest species numbers (S = 63) and richness (d = 12.16) with a high evenness of species (J = 0.9377) during the peak of the wet season;and the lowest species numbers (S = 58) and Margalef’s index of (d = 10.14) in January. The highest Shannon diversity index of (H = 3.927) was recorded at Dagomba in January.展开更多
We study the dissociation of strictly confined charmonium states at finite temperature.The strict confinement constraint to the Cornell potential leads to a 10%higher J/(φ)dissociation temperature and in turn a weake...We study the dissociation of strictly confined charmonium states at finite temperature.The strict confinement constraint to the Cornell potential leads to a 10%higher J/(φ)dissociation temperature and in turn a weaker J/(φ)suppression in relativistic heavy ion collisions.展开更多
This paper proposes a new hybrid variant of extragradient methods for finding a common solution of an equilibrium problem and a family of strict pseudo-contraction mappings. We present an algorithmic scheme that combi...This paper proposes a new hybrid variant of extragradient methods for finding a common solution of an equilibrium problem and a family of strict pseudo-contraction mappings. We present an algorithmic scheme that combine the idea of an extragradient method and a successive iteration method as a hybrid variant. Then, this algorithm is modified by projecting on a suitable convex set to get a better convergence property. The convergence of two these algorithms are investigated under certain assumptions.展开更多
We give a characterization of the boundaries of smooth strictly convex sets in the Euclidean plane R2?based on the existence and uniqueness of inscribed triangles.
The magnetostriction of polycrystal RFe_(11)Ti(R=Nd,Sm,Gd,Tb,Dy,Ho,Er and Y)and RFe_(10)Cr_(2)(R=Tb and Dy)compounds with ThMn_(12)-typestructure have been investigated at 77K and room temperature in magnetic fields u...The magnetostriction of polycrystal RFe_(11)Ti(R=Nd,Sm,Gd,Tb,Dy,Ho,Er and Y)and RFe_(10)Cr_(2)(R=Tb and Dy)compounds with ThMn_(12)-typestructure have been investigated at 77K and room temperature in magnetic fields up to 20kOe.The values of magnetastriction λ_(t)=λ_(||)-λ_(⊥)in H=20kOe at 300K are 180×10^(-6) for TbFe_(11)Ti and 106×10^(-6)for Tb_(10)Cr_(2).The magnetostrictions for compounds with R=Nd,Sm,Dy,Ho and Er are very small.The signs ofλt for all these compounds are in agreement with that predicted by the singleion crystal field theory.All studied samples show a volume magnetostriction feature.Their forced magnetostrictionsΔω/ΔH have a value which is close to that of YFe_(11)Ti,27×10^(-10)/Oe.It reveals that the Fe sublattice is responsible for the volumc magnetostriction.展开更多
The distributed leader-following consensus for nonlinear multi-agent systems in strict-feedback forms is investigated under directed topology. Firstly, each follower node is modeled by an integrator incorporating with...The distributed leader-following consensus for nonlinear multi-agent systems in strict-feedback forms is investigated under directed topology. Firstly, each follower node is modeled by an integrator incorporating with nonlinear dynamics. The leader node is modeled as an autonomous nonlinear system which sends its information to one or more followers. Then, a simple and novel distributed protocol is proposed based only on the state feedback, under which the states of the followers ultimately synchronize to the leader. By using Lyapunov stability theorem and matrix theory, it is proved that the distributed leader-following consensus of nonlinear multi-agent systems with strict-feedback form is guaranteed by Lipschitz continuous control laws. Finally, some numerical simulations are provided to show the effectiveness of the developed method.展开更多
Though Beijing is the capital of China, it used to suffer from sand and dust storms, due to human activities, geographical environment and windy and dry climate. However, after decades of efforts, we now embrace the b...Though Beijing is the capital of China, it used to suffer from sand and dust storms, due to human activities, geographical environment and windy and dry climate. However, after decades of efforts, we now embrace the blue sky in Beijing for most days of a year.展开更多
In this paper, a fuzzy adaptive tracking control for uncertain strict-feedback nonlinear systems with unknown bounded disturbances is proposed. The generalized fuzzy hyperbolic model (GFHM) with better approximation p...In this paper, a fuzzy adaptive tracking control for uncertain strict-feedback nonlinear systems with unknown bounded disturbances is proposed. The generalized fuzzy hyperbolic model (GFHM) with better approximation performance is used to approximate the unknown nonlinear function in the system. The dynamic surface control (DSC) is used to design the controller, which not only avoids the “explosion of complexity” problem in the process of repeated derivation, but also makes the control system simpler in structure and lower in computational cost because only one adaptive law is designed in the controller design process. Through the Lyapunov stability analysis, all signals in the closed loop system designed in this paper are semi-globally uniformly ultimately bounded (SGUUB). Finally, the effectiveness of the method is verified by a simulation example.展开更多
基金supported by the National Natural Science Foundation of China(31801979)State Key Laboratory of Integrated Management of Pest Insects and Rodents,Institute of Zoology,Chinese Academy of Sciences(IPM2208)。
文摘DEAR EDITOR,We identified strict monandry in a wandering wolf spider species(Pardosa pseudoannulata) and revealed the underlying mechanisms of this mating structure. Evidence indicated that males damaged the inner walls of the female genital tract with the sharp part of their intromittent organ during insemination. The traumatic mating caused hemolymph hemorrhage, which mixed with seminal fluid and gradually formed an impermeable amorphous mating plug after about15 days, completely blocking the female copulatory opening.
基金Supported by The Creation of Innovation Centers for Advanced Interdisciplinary Research Areas Program that was part of the Project for Developing Innovation Systems by the Cell Sheet Tissue Engineering Center from the Ministry of Education,Culture,Sports,Science and Technology,Japan
文摘Endoscopic mucosal resection(EMR) and endoscopic submucosal dissection(ESD) have recently been accepted as less invasive methods for treating patients with early esophageal cancers such as squamous cell carcinoma and dysplasia of Barrett's esophagus.However,the large defects in the esophageal mucosa often cause severe esophageal strictures,which dramatically reduce the patient's quality of life.Although preventive endoscopic balloon dilatation can reduce dysphagia and the frequency of dilatation,other approaches are necessary to prevent esophageal strictures after ESD.This review describes several strategies for preventing esophageal strictures after ESD,with a particular focus on anti-inflammatory and tissue engineering approaches.The local injection of triamcinolone acetonide and other systemic steroid therapies are frequently used to prevent esophageal strictures after ESD.Tissue engineering approaches for preventing esophageal strictures have recently been applied in basic research studies.Scaffolds with temporary stents have been applied in five cases,and this technique has been shown to be safe and is anticipated to prevent esophageal strictures.Fabricated autologous oral mucosal epithelial cell sheets to cover the defective mucosa similarly to how commercially available skin products fabricated from epidermal cells are used for skin defects or in cases of intractable ulcers.Fabricated autologous oralmucosal-epithelial cell sheets have already been shown to be safe.
文摘In this paper we use the notion of measure of non-strict-singularity to give some results on Fredholm operators and we establish a fine description of the Schechter essential spectrum of a closed densely defined linear operator.
基金Supported by the National Natural Science Foundation of China（71261010）
文摘Generalized strictly diagonally dominant matrices play a wide and important role in computational mathematics, mathematical physics, theory of dynamical systems, etc.But it is difficult to judge a matrix is or not generalized strictly diagonally dominant matrix.In this paper, by using the properties of α-chain diagonally dominant matrix, we obtain new criteria for judging generalized strictly diagonally dominant matrix, which enlarge the identification range.
文摘A generalized Lyness equation is investigated as follows x n+1 =x n(a+bx n )x n-1 , n=0,1,2,…,(*) where a,b∈[0,∞) with a+b>0 and where the initial values x -1 ,x 0 are arbitrary positive numbers. Some new results, mainly a necessary and sufficient condition for the periodicity of the solutions of Eq.(*) and a sufficient condition for the strict oscillation of all solutions of Eq(*),are obtained. As an application, the results solve an open problem presented by G.Ladas.
基金supported by the National Natural Science Foundation of China(12001416,11771347 and 12031003)the Natural Science Foundations of Shaanxi Province(2021JQ-678).
文摘In this paper,we introduce a general hybrid iterative method to find an infinite family of strict pseudo-contractions in a q-uniformly smooth and strictly convex Banach space.Moreover,we show that the sequence defined by the iterative method converges strongly to a common element of the set of fixed points,which is the unique solution of the variational inequality<(λφ−νF)z,jq(z−z)>≤0,for z∈⋂_(i=1)^(∞)Γ(S_(i)).The results introduced in our work extend to some corresponding theorems.
文摘What lurks within the crypt?With more than 200 known causes of is chemic stroke(Saver,2016),what should be the minimum work up?Many centers offer high-resolution brain imaging and vessel studies,telemetry monitoring for atrial fibrillation(AF),trans-thoracic and transesophageal echocardiography.
文摘Kogyae Strict Nature Reserve, the only one in Ghana, was established to promote scientific research, particularly on how nature revitalizes itself after major disasters, and also to check the southward drift of the savannah grassland. This study presents the first comprehensive inventory of species composition and diversity of insects of the Reserve. Insects were surveyed between September 2011 and June 2012 to capture the end of the rainy season, the dry season and the peak of the wet season. Samples were taken from two sites within the Reserve, Dagomba and Oku using various sampling techniques including pitfall traps, malaise traps and sweep nets. Insect communities were characterized in terms of, 1) species richness estimators, 2) species richness, 3) Shannon-Weiner Index of Diversity, 4) Pielou’s evenness and 5) Bray-Curtis similarity. A total of 8147 individuals representing 135 families from 21 orders were recorded. This included 107 species of butterflies from 9 families and 20 species of dragonflies from 3 families. Oku recorded the highest species numbers (S = 63) and richness (d = 12.16) with a high evenness of species (J = 0.9377) during the peak of the wet season;and the lowest species numbers (S = 58) and Margalef’s index of (d = 10.14) in January. The highest Shannon diversity index of (H = 3.927) was recorded at Dagomba in January.
基金Supported by the National Natural Science Foundation of China under Grant Nos 10847001,10975084 and 11079024.
文摘We study the dissociation of strictly confined charmonium states at finite temperature.The strict confinement constraint to the Cornell potential leads to a 10%higher J/(φ)dissociation temperature and in turn a weaker J/(φ)suppression in relativistic heavy ion collisions.
文摘This paper proposes a new hybrid variant of extragradient methods for finding a common solution of an equilibrium problem and a family of strict pseudo-contraction mappings. We present an algorithmic scheme that combine the idea of an extragradient method and a successive iteration method as a hybrid variant. Then, this algorithm is modified by projecting on a suitable convex set to get a better convergence property. The convergence of two these algorithms are investigated under certain assumptions.
文摘We give a characterization of the boundaries of smooth strictly convex sets in the Euclidean plane R2?based on the existence and uniqueness of inscribed triangles.
文摘The magnetostriction of polycrystal RFe_(11)Ti(R=Nd,Sm,Gd,Tb,Dy,Ho,Er and Y)and RFe_(10)Cr_(2)(R=Tb and Dy)compounds with ThMn_(12)-typestructure have been investigated at 77K and room temperature in magnetic fields up to 20kOe.The values of magnetastriction λ_(t)=λ_(||)-λ_(⊥)in H=20kOe at 300K are 180×10^(-6) for TbFe_(11)Ti and 106×10^(-6)for Tb_(10)Cr_(2).The magnetostrictions for compounds with R=Nd,Sm,Dy,Ho and Er are very small.The signs ofλt for all these compounds are in agreement with that predicted by the singleion crystal field theory.All studied samples show a volume magnetostriction feature.Their forced magnetostrictionsΔω/ΔH have a value which is close to that of YFe_(11)Ti,27×10^(-10)/Oe.It reveals that the Fe sublattice is responsible for the volumc magnetostriction.
基金National Natural Science Foundation of China(No.61374024)
文摘The distributed leader-following consensus for nonlinear multi-agent systems in strict-feedback forms is investigated under directed topology. Firstly, each follower node is modeled by an integrator incorporating with nonlinear dynamics. The leader node is modeled as an autonomous nonlinear system which sends its information to one or more followers. Then, a simple and novel distributed protocol is proposed based only on the state feedback, under which the states of the followers ultimately synchronize to the leader. By using Lyapunov stability theorem and matrix theory, it is proved that the distributed leader-following consensus of nonlinear multi-agent systems with strict-feedback form is guaranteed by Lipschitz continuous control laws. Finally, some numerical simulations are provided to show the effectiveness of the developed method.
文摘Though Beijing is the capital of China, it used to suffer from sand and dust storms, due to human activities, geographical environment and windy and dry climate. However, after decades of efforts, we now embrace the blue sky in Beijing for most days of a year.
文摘In this paper, a fuzzy adaptive tracking control for uncertain strict-feedback nonlinear systems with unknown bounded disturbances is proposed. The generalized fuzzy hyperbolic model (GFHM) with better approximation performance is used to approximate the unknown nonlinear function in the system. The dynamic surface control (DSC) is used to design the controller, which not only avoids the “explosion of complexity” problem in the process of repeated derivation, but also makes the control system simpler in structure and lower in computational cost because only one adaptive law is designed in the controller design process. Through the Lyapunov stability analysis, all signals in the closed loop system designed in this paper are semi-globally uniformly ultimately bounded (SGUUB). Finally, the effectiveness of the method is verified by a simulation example.
