The very low cut-off value for sperm morphology of 4% morphologically normal spermatozoa, as proposed in the new edition of the World Health Organization （WHO） manual on semen analysis, is in agreement with recently...The very low cut-off value for sperm morphology of 4% morphologically normal spermatozoa, as proposed in the new edition of the World Health Organization （WHO） manual on semen analysis, is in agreement with recently published values and reflects the trend of a decline in reported mean values for normal sperm morphology. The reduced value for morphologically normal spermatozoa over the years may be due to several factors. The first is the introduction of strict criteria for the evaluation of sperm morphology. Other reasons may include the introduction of additional criteria for sperm morphology abnormalities and the suggested decrease in semen parameters because of increasing negative environmental influences. Although on its own the newly proposed very low normal value may not provide the strong predictive value for a males＇ fertility potential, as originally reported for sperm morphology evaluated according to strict criteria, a good predictive value can still be obtained if the holistic, strict approach for sperm morphology evaluation is followed together with additional sperm morphology parameters now available, because certain morphology patterns and sperm abnormalities are now known to be of strong prognostic value. In addition, better international standardization of the technical methodology, consensus on the interpretation of sperm morphology evaluation criteria and standardized international external quality control （EQC） schemes, are of utmost importance to maintain the good predictive value of sperm morphology.展开更多
The measurement or evaluation and clinical significance of human sperm morphology has always been and still is a controversial aspect of the semen analysis for the determination of a male＇s fertility potential. In th...The measurement or evaluation and clinical significance of human sperm morphology has always been and still is a controversial aspect of the semen analysis for the determination of a male＇s fertility potential. In this review the background of the development of the evaluation criteria for sperm morphology will be discussed. Aspects of criticism on the strict criteria definition and use of the criteria for sperm morphology evaluation will be discussed as well as possible reasons for the decline in normal sperm morphology values and how we can compromise for this phenomenon resulting in the very low normal reference value as published in the 2010 WHO manual for the Examination and Processing of Human Semen. One of the possible solutions may be to give more attention to a limited number of abnormal sperm morphology categories and the inclusion of sperm morphology patterns. It is concluded in this review that if done correctly and with care and with strict application of existing guidelines as outlined in the 2010 WHO manual, sperm morphology measurement still has a very important role to play in the clinical evaluation of male fertility potential.展开更多
We introduce a new class of nonnegative tensors—strictly nonnegative tensors.A weakly irreducible nonnegative tensor is a strictly nonnegative tensor but not vice versa.We show that the spectral radius of a strictly ...We introduce a new class of nonnegative tensors—strictly nonnegative tensors.A weakly irreducible nonnegative tensor is a strictly nonnegative tensor but not vice versa.We show that the spectral radius of a strictly nonnegative tensor is always positive.We give some necessary and su?cient conditions for the six wellconditional classes of nonnegative tensors,introduced in the literature,and a full relationship picture about strictly nonnegative tensors with these six classes of nonnegative tensors.We then establish global R-linear convergence of a power method for finding the spectral radius of a nonnegative tensor under the condition of weak irreducibility.We show that for a nonnegative tensor T,there always exists a partition of the index set such that every tensor induced by the partition is weakly irreducible;and the spectral radius of T can be obtained from those spectral radii of the induced tensors.In this way,we develop a convergent algorithm for finding the spectral radius of a general nonnegative tensor without any additional assumption.Some preliminary numerical results show the feasibility and effectiveness of the algorithm.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 an...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 oral-mucosal-epithelial cell sheets have already been shown to be safe.展开更多
In couples with infertility, abnormal strict morphology of 0% normal forms （NF） is a criterion to proceed rapidly to in vitro fertilization （IVF）. Since no data currently exist, we investigated the outcomes for me...In couples with infertility, abnormal strict morphology of 0% normal forms （NF） is a criterion to proceed rapidly to in vitro fertilization （IVF）. Since no data currently exist, we investigated the outcomes for men with 0% NF to determine reproductive success without the use of assisted reproductive technologies （ART）. A cohort of 24 men with 0% NF were identified （2010-2013） with 27 randomly selected men with 〉4% NF as controls. Patient charts were reviewed with men contacted and administered an Institutional Review Board （IRB）-approved telephone questionnaire to ascertain outcomes. After a median follow-up time of 2.5 years, 29.2% of men with 0% NF did not require ART for their first pregnancy （controls = 55.6%, P〈 0.05）. When all pregnancies were analyzed together, men with 0% NF achieved twenty pregnancies of which 75% did not require IVF （controls - thirty pregnancies; 76.7% did not require IVF）. The average age of men and female partners was similar between men with 0% NF and 〉4% NF. All men had normal follicle-stimulating hormone （FSH）, testosterone, prolactin, sex hormone-binding globulin （SHBG）, and estradiol. Although, global semen parameters were worse in men with 0% NF, when a first pregnancy was a natural conception （NC）, 100% of men with 0% NF （n = 7/7） and 37.5% of controls in = 3/8） went on to have a subsequent pregnancy via NC. Men with 0% NF conceived without IVF in 29.2% of cases compared to 55.6% of controls. Strict morphology should not be used to predict fertilization, pregnancy, or live birth potential. In men with 0% NF, alternative modalities should be considered before immediate IVF.展开更多
A class of plateaued functions has been got by using the Maiorana-McFarland construction. A variety of desirable criteria for functions with cryptographic application eouht be satisfied： balancedness, high nonlineari...A class of plateaued functions has been got by using the Maiorana-McFarland construction. A variety of desirable criteria for functions with cryptographic application eouht be satisfied： balancedness, high nonlinearity, correlation immunity of reasonably high order, strict avalanche criterion, non-existence of non-zero linear struetures, good glnbal avalanche characteristics, etc.展开更多
Camptothecin is one of the most commonly used anticancer drugs worldwide,yet the downstream biosynthetic route from strictosidine to camptothecin has remained unclear for more than half a century.Here,we searched for ...Camptothecin is one of the most commonly used anticancer drugs worldwide,yet the downstream biosynthetic route from strictosidine to camptothecin has remained unclear for more than half a century.Here,we searched for proteins involved in camptothecin biosynthesis from the camptothecin-producing plant Ophiorrhiza pumila by chemoproteomics and identified Op CYP716E111.展开更多
In this paper, a new mixed quasi-Newton method for inequality constrained optimization problems is proposed. The feature of the method is that only the systems of linear equations are solved in each iteration, other t...In this paper, a new mixed quasi-Newton method for inequality constrained optimization problems is proposed. The feature of the method is that only the systems of linear equations are solved in each iteration, other than the quadratic programming, which decrease the amount of computations and is also efficient for large scale problem. Under some mild assumptions without the strict complementary condition., the method is globally and superlinearly convergent.展开更多
We study the closed range property and the strict singularity of integration operators acting on the spaces F(p,pα-2,s).We completely characterize the closed range property of the Volterra companion operator I_(g)on ...We study the closed range property and the strict singularity of integration operators acting on the spaces F(p,pα-2,s).We completely characterize the closed range property of the Volterra companion operator I_(g)on F(p,pα-2,s),which generalizes the existing results and answers a question raised in[A.Anderson,Integral Equations Operator Theory,69(2011),no.1,87-99].For the Volterra operator J_(g),we show that,for 0<α≤1,J_(g)never has a closed range on F(p,pα-2,s).We then prove that the notions of compactness,weak compactness and strict singularity coincide in the case of J_(g)acting on F(p,p-2,s).展开更多
In this paper,fixed-time consensus tracking for mul-tiagent systems(MASs)with dynamics in the form of strict feed-back affine nonlinearity is addressed.A fixed-time antidistur-bance consensus tracking protocol is prop...In this paper,fixed-time consensus tracking for mul-tiagent systems(MASs)with dynamics in the form of strict feed-back affine nonlinearity is addressed.A fixed-time antidistur-bance consensus tracking protocol is proposed,which consists of a distributed fixed-time observer,a fixed-time disturbance observer,a nonsmooth antidisturbance backstepping controller,and the fixed-time stability analysis is conducted by using the Lyapunov theory correspondingly.This paper includes three main improvements.First,a distributed fixed-time observer is developed for each follower to obtain an estimate of the leader’s output by utilizing the topology of the communication network.Second,a fixed-time disturbance observer is given to estimate the lumped disturbances for feedforward compensation.Finally,a nonsmooth antidisturbance backstepping tracking controller with feedforward compensation for lumped disturbances is designed.In order to mitigate the“explosion of complexity”in the tradi-tional backstepping approach,we have implemented a modified nonsmooth command filter to enhance the performance of the closed-loop system.The simulation results show that the pro-posed method is effective.展开更多
Online petulance broke out after China Railway surveyed passengers on whether to allow pets on trains,while experts said that strict rules are needed before cats and dogs are riding the rails.
During the multistep process of metastasis,cancer cells encounter various mechanical forces which make them deform drastically.Developing accurate in-silico models,capable of simulating the interactions between the me...During the multistep process of metastasis,cancer cells encounter various mechanical forces which make them deform drastically.Developing accurate in-silico models,capable of simulating the interactions between the mechanical forces and highly deformable cancer cells,can pave the way for the development of novel diagnostic and predictive methods for metastatic progression.Spring-network models of cancer cell,empowered by our recently proposed identification approach,promises a versatile numerical tool for developing experimentally validated models that can simulate complex interactions at cellular scale.Using this numerical tool,we presented spring-network models of breast cancer cells that can accurately replicate the experimental data of deformation behavior of the cells flowing in a fluidic domain and passing narrow constrictions comparable to microcapillary.First,using high-speed imaging,we experimentally studied the deformability of breast cancer cell lines with varying metastatic potential(MCF-7(less invasive),SKBR-3(medium-high invasive),and MDA-MB-231(highly invasive)in terms of their entry time to a constricted microfluidic channel.We observed that MDA-MB-231,that has the highest metastatic potential,is the most deformable cell among the three.Then,by focusing on this cell line,experimental measurements were expanded to two more constricted microchannel dimensions.The experimental deformability data in three constricted microchannel sizes for various cell sizes,enabled accurate identification of the unknown parameters of the spring-network model of the breast cancer cell line(MDA-MB-231).Our results show that the identifed parameters depend on the cell size,suggesting the need for a systematic procedure for identifying the size-dependent parameters of spring-network models of cells.As the numerical results show,the presented cell models can simulate the entry process of the cell into constricted channels with very good agreements with the measured experimental data.展开更多
文摘The very low cut-off value for sperm morphology of 4% morphologically normal spermatozoa, as proposed in the new edition of the World Health Organization （WHO） manual on semen analysis, is in agreement with recently published values and reflects the trend of a decline in reported mean values for normal sperm morphology. The reduced value for morphologically normal spermatozoa over the years may be due to several factors. The first is the introduction of strict criteria for the evaluation of sperm morphology. Other reasons may include the introduction of additional criteria for sperm morphology abnormalities and the suggested decrease in semen parameters because of increasing negative environmental influences. Although on its own the newly proposed very low normal value may not provide the strong predictive value for a males＇ fertility potential, as originally reported for sperm morphology evaluated according to strict criteria, a good predictive value can still be obtained if the holistic, strict approach for sperm morphology evaluation is followed together with additional sperm morphology parameters now available, because certain morphology patterns and sperm abnormalities are now known to be of strong prognostic value. In addition, better international standardization of the technical methodology, consensus on the interpretation of sperm morphology evaluation criteria and standardized international external quality control （EQC） schemes, are of utmost importance to maintain the good predictive value of sperm morphology.
文摘The measurement or evaluation and clinical significance of human sperm morphology has always been and still is a controversial aspect of the semen analysis for the determination of a male＇s fertility potential. In this review the background of the development of the evaluation criteria for sperm morphology will be discussed. Aspects of criticism on the strict criteria definition and use of the criteria for sperm morphology evaluation will be discussed as well as possible reasons for the decline in normal sperm morphology values and how we can compromise for this phenomenon resulting in the very low normal reference value as published in the 2010 WHO manual for the Examination and Processing of Human Semen. One of the possible solutions may be to give more attention to a limited number of abnormal sperm morphology categories and the inclusion of sperm morphology patterns. It is concluded in this review that if done correctly and with care and with strict application of existing guidelines as outlined in the 2010 WHO manual, sperm morphology measurement still has a very important role to play in the clinical evaluation of male fertility potential.
基金supported by National Natural Science Foundation of China (Grant No. 11171252)the Hong Kong Research Grant Council (Grant Nos. PolyU 501909,502510,502111 and 501212)
文摘We introduce a new class of nonnegative tensors—strictly nonnegative tensors.A weakly irreducible nonnegative tensor is a strictly nonnegative tensor but not vice versa.We show that the spectral radius of a strictly nonnegative tensor is always positive.We give some necessary and su?cient conditions for the six wellconditional classes of nonnegative tensors,introduced in the literature,and a full relationship picture about strictly nonnegative tensors with these six classes of nonnegative tensors.We then establish global R-linear convergence of a power method for finding the spectral radius of a nonnegative tensor under the condition of weak irreducibility.We show that for a nonnegative tensor T,there always exists a partition of the index set such that every tensor induced by the partition is weakly irreducible;and the spectral radius of T can be obtained from those spectral radii of the induced tensors.In this way,we develop a convergent algorithm for finding the spectral radius of a general nonnegative tensor without any additional assumption.Some preliminary numerical results show the feasibility and effectiveness of the algorithm.
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 oral-mucosal-epithelial cell sheets have already been shown to be safe.
文摘In couples with infertility, abnormal strict morphology of 0% normal forms （NF） is a criterion to proceed rapidly to in vitro fertilization （IVF）. Since no data currently exist, we investigated the outcomes for men with 0% NF to determine reproductive success without the use of assisted reproductive technologies （ART）. A cohort of 24 men with 0% NF were identified （2010-2013） with 27 randomly selected men with 〉4% NF as controls. Patient charts were reviewed with men contacted and administered an Institutional Review Board （IRB）-approved telephone questionnaire to ascertain outcomes. After a median follow-up time of 2.5 years, 29.2% of men with 0% NF did not require ART for their first pregnancy （controls = 55.6%, P〈 0.05）. When all pregnancies were analyzed together, men with 0% NF achieved twenty pregnancies of which 75% did not require IVF （controls - thirty pregnancies; 76.7% did not require IVF）. The average age of men and female partners was similar between men with 0% NF and 〉4% NF. All men had normal follicle-stimulating hormone （FSH）, testosterone, prolactin, sex hormone-binding globulin （SHBG）, and estradiol. Although, global semen parameters were worse in men with 0% NF, when a first pregnancy was a natural conception （NC）, 100% of men with 0% NF （n = 7/7） and 37.5% of controls in = 3/8） went on to have a subsequent pregnancy via NC. Men with 0% NF conceived without IVF in 29.2% of cases compared to 55.6% of controls. Strict morphology should not be used to predict fertilization, pregnancy, or live birth potential. In men with 0% NF, alternative modalities should be considered before immediate IVF.
基金the National Natural Science Foundation of China，Foundation of National Laboratory for Modern Communications
文摘A class of plateaued functions has been got by using the Maiorana-McFarland construction. A variety of desirable criteria for functions with cryptographic application eouht be satisfied： balancedness, high nonlinearity, correlation immunity of reasonably high order, strict avalanche criterion, non-existence of non-zero linear struetures, good glnbal avalanche characteristics, etc.
基金supported financially by the National Key Research and Development Program of China(Grant No.2018YFA0900700)the National Natural Science Foundation of China(Nos.31901021+1 种基金31921006)the Strategic Biological Resources Service Network Plan of the Chinese Academy of Sciences(Grant No.KFJ-BRP009)。
文摘Camptothecin is one of the most commonly used anticancer drugs worldwide,yet the downstream biosynthetic route from strictosidine to camptothecin has remained unclear for more than half a century.Here,we searched for proteins involved in camptothecin biosynthesis from the camptothecin-producing plant Ophiorrhiza pumila by chemoproteomics and identified Op CYP716E111.
文摘In this paper, a new mixed quasi-Newton method for inequality constrained optimization problems is proposed. The feature of the method is that only the systems of linear equations are solved in each iteration, other than the quadratic programming, which decrease the amount of computations and is also efficient for large scale problem. Under some mild assumptions without the strict complementary condition., the method is globally and superlinearly convergent.
基金partially supported by the Fundamental Research Funds for the Central Universities(GK202207018)of China。
文摘We study the closed range property and the strict singularity of integration operators acting on the spaces F(p,pα-2,s).We completely characterize the closed range property of the Volterra companion operator I_(g)on F(p,pα-2,s),which generalizes the existing results and answers a question raised in[A.Anderson,Integral Equations Operator Theory,69(2011),no.1,87-99].For the Volterra operator J_(g),we show that,for 0<α≤1,J_(g)never has a closed range on F(p,pα-2,s).We then prove that the notions of compactness,weak compactness and strict singularity coincide in the case of J_(g)acting on F(p,p-2,s).
基金supported by the National Defense Basic Scientific Research Project(JCKY2020130C025)the National Science and Technology Major Project(J2019-III-0020-0064,J2019-V-0014-0109)。
文摘In this paper,fixed-time consensus tracking for mul-tiagent systems(MASs)with dynamics in the form of strict feed-back affine nonlinearity is addressed.A fixed-time antidistur-bance consensus tracking protocol is proposed,which consists of a distributed fixed-time observer,a fixed-time disturbance observer,a nonsmooth antidisturbance backstepping controller,and the fixed-time stability analysis is conducted by using the Lyapunov theory correspondingly.This paper includes three main improvements.First,a distributed fixed-time observer is developed for each follower to obtain an estimate of the leader’s output by utilizing the topology of the communication network.Second,a fixed-time disturbance observer is given to estimate the lumped disturbances for feedforward compensation.Finally,a nonsmooth antidisturbance backstepping tracking controller with feedforward compensation for lumped disturbances is designed.In order to mitigate the“explosion of complexity”in the tradi-tional backstepping approach,we have implemented a modified nonsmooth command filter to enhance the performance of the closed-loop system.The simulation results show that the pro-posed method is effective.
文摘Online petulance broke out after China Railway surveyed passengers on whether to allow pets on trains,while experts said that strict rules are needed before cats and dogs are riding the rails.
基金supported by the Natural Sciences and Engineering Research Council of Canada(RGPIN-2020-05522&RGPIN-2020-00428).
文摘During the multistep process of metastasis,cancer cells encounter various mechanical forces which make them deform drastically.Developing accurate in-silico models,capable of simulating the interactions between the mechanical forces and highly deformable cancer cells,can pave the way for the development of novel diagnostic and predictive methods for metastatic progression.Spring-network models of cancer cell,empowered by our recently proposed identification approach,promises a versatile numerical tool for developing experimentally validated models that can simulate complex interactions at cellular scale.Using this numerical tool,we presented spring-network models of breast cancer cells that can accurately replicate the experimental data of deformation behavior of the cells flowing in a fluidic domain and passing narrow constrictions comparable to microcapillary.First,using high-speed imaging,we experimentally studied the deformability of breast cancer cell lines with varying metastatic potential(MCF-7(less invasive),SKBR-3(medium-high invasive),and MDA-MB-231(highly invasive)in terms of their entry time to a constricted microfluidic channel.We observed that MDA-MB-231,that has the highest metastatic potential,is the most deformable cell among the three.Then,by focusing on this cell line,experimental measurements were expanded to two more constricted microchannel dimensions.The experimental deformability data in three constricted microchannel sizes for various cell sizes,enabled accurate identification of the unknown parameters of the spring-network model of the breast cancer cell line(MDA-MB-231).Our results show that the identifed parameters depend on the cell size,suggesting the need for a systematic procedure for identifying the size-dependent parameters of spring-network models of cells.As the numerical results show,the presented cell models can simulate the entry process of the cell into constricted channels with very good agreements with the measured experimental data.
