In order to save energy and make more efficient use of wireless channel, this article puts forward an energy saving cooperative relaying scheme which actuates the cooperative transmis- sion only when the feedback from...In order to save energy and make more efficient use of wireless channel, this article puts forward an energy saving cooperative relaying scheme which actuates the cooperative transmis- sion only when the feedback from the destination indicates failure of the direct transmission. The proposed scheme selects the optimal relay and its corresponding transmission power in each time slot based on channel condition and residual ener- gy with the objective of minimizing energy con- sumption and extending network lifetime. In the study, the f＇mite-state Markov channel model is used to characterize the correlation structure of channel fading in wireless networks, and the pro- cedure of relay selection and transmission power decision is formulated as a M arkov decision process. Numerical and simulation results show that the proposed scheme consumes less energy and prolongs the network lifetime.展开更多
Cooperative spectrum sensing in cog- nitive radio is investigated to improve the det- ection performance of Primary User （PU）. Meanwhile, cluster-based hierarchical coop- eration is introduced for reducing the overh...Cooperative spectrum sensing in cog- nitive radio is investigated to improve the det- ection performance of Primary User （PU）. Meanwhile, cluster-based hierarchical coop- eration is introduced for reducing the overhead as well as maintaining a certain level of sens- ing performance. However, in existing hierar- chically cooperative spectrum sensing algo- rithms, the robustness problem of the system is seldom considered. In this paper, we pro- pose a reputation-based hierarchically coop- erative spectrum sensing scheme in Cognitive Radio Networks （CRNs）. Before spectrum sensing, clusters are grouped based on the location correlation coefficients of Secondary Users （SUs）. In the proposed scheme, there are two levels of cooperation, the first one is performed within a cluster and the second one is carried out among clusters. With the reputa- tion mechanism and modified MAJORITY rule in the second level cooperation, the pro- posed scheme can not only relieve the influ- ence of the shadowing, but also eliminate the impact of the PU emulation attack on a rela- tively large scale. Simulation results show that, in the scenarios with deep-shadowing or mul- tiple attacked SUs, our proposed scheme ach- ieves a better tradeoff between the system robustness and the energy saving compared with those conventionally cooperative sensing schemes.展开更多
Genotype of IgH, TCRγ and TCR δ gene rearrangement in 42 cases of malignant lymphoproliferative disorders were studied by using polymerase chain reaction (PCR) technique. The results suggested that among the 23 case...Genotype of IgH, TCRγ and TCR δ gene rearrangement in 42 cases of malignant lymphoproliferative disorders were studied by using polymerase chain reaction (PCR) technique. The results suggested that among the 23 cases, in which malignant cells expressed B-lineage cell surface markers, 20 showed IgH gene rearrangement and 11 had TCRγ gene rearrangement and / or TCRδ gene deletion. All the 11 cases expressed T-lineage cell differentiation antigens were found to have TCRγand TCRδ gene rearrangement or deletion and only one had IgH gene rearrangement. Double rearrangements of IgH and TCRγ genes were detected in all the 3 cases of T and B double-phenotype ALL. In the cases malignant cells did not express any lineage specific antigens while 4/5 had TCRγ gene rearrangement but all failed in IgH gene rearrangement. The relation of cellular differentiation origin and rearrangement of antigen receptor genes with clinical manifestations was discussed.展开更多
The classification of lung nodules is a challenging problem as the visual analysis of the nodules and non-nodules revealed homogenous textural patterns.In this work,an Auxiliary Classifier(AC)-Generative Adversarial Net...The classification of lung nodules is a challenging problem as the visual analysis of the nodules and non-nodules revealed homogenous textural patterns.In this work,an Auxiliary Classifier(AC)-Generative Adversarial Network(GAN)based Lung Cancer Classification(LCC)system is developed.The pro-posed AC-GAN-LCC system consists of three modules;preprocessing,Lungs Region Detection(LRD),and AC-GAN classification.A Wienerfilter is employed in the preprocessing module to remove the Gaussian noise.In the LRD module,only the lung regions(left and right lungs)are detected using itera-tive thresholding and morphological operations.In order to extract the lung region only,floodfilling and background subtraction.The detected lung regions are fed to the AC-GAN classifier to detect the nodules.It classifies the nodules into one of the two classes,i.e.,binary classification(such as nodules or non-nodules).The AC-GAN is the extended version of the conditional GAN that predicts the label of a given image.Three different optimization techniques,adaptive gradient optimi-zation,root mean square propagation optimization,and Adam optimization are employed for optimizing the AC-GAN architecture.The proposed AC-GAN-LCC system is evaluated on the Lung Image Database Consortium(LIDC)data-base Computed Tomography(CT)scan images.The proposed AC-GAN-LCC system classifies∼15000 CT slices(7310 non-nodules and 7685 nodules).It pro-vides an overall accuracy of 98.8%on the LIDC database using Adam optimiza-tion by a 10-fold cross-validation approach.展开更多
In the field of L2 （second language） reading, scholars generally agree that ER （extensive reading） improves L2 learners＇ reading speed and comprehension and enriches their L2 vocabulary （Grabe ＆ Stoller, 1997）...In the field of L2 （second language） reading, scholars generally agree that ER （extensive reading） improves L2 learners＇ reading speed and comprehension and enriches their L2 vocabulary （Grabe ＆ Stoller, 1997）. This teacher-inquiry type of paper presents a practical suggestion for supplementing ER activity with the element of CL （cooperative learning）. ER, theoretically speaking, focuses on the solitary task of silent reading. The CL technique used in this study was a book-talk activity. Forty-five freshmen from a course of children and young adult literatures were required to read at least 20 English books throughout a semester. CL was added to facilitate students＇ ER in young adult literature. After a semester, short-answer questions were asked regarding students＇ comments on ER as well as CL. Students overall agreed that when ER is supplemented with CL, reading in an L2 seems to be less intimidating.展开更多
We report on cooperative quantum cutting in Tb^3＋- Yb^3＋ codoped glass ceramics. Precipitation of BaF2 nanocrystals is confirmed by XRD and HRTEM analysis. Near-infrared emission due to transition of Yb^3＋ ions und...We report on cooperative quantum cutting in Tb^3＋- Yb^3＋ codoped glass ceramics. Precipitation of BaF2 nanocrystals is confirmed by XRD and HRTEM analysis. Near-infrared emission due to transition of Yb^3＋ ions under 485 nm excitation indicates cooperative energy transfer from Tb^3＋ to Yb^3＋. The quantum efficiency of this process reaches 145%. The realization of quantum cutting in glass ceramics may have promising applications in solar cells.展开更多
Potassium channels regulate diverse biological processes,ranging from cell proliferation to immune responses.However,the functions of potassium homeostasis and its regulatory mechanisms in adult stem cells and tumors ...Potassium channels regulate diverse biological processes,ranging from cell proliferation to immune responses.However,the functions of potassium homeostasis and its regulatory mechanisms in adult stem cells and tumors remain poorly characterized.Here,we identify Sandman(Sand),a two-pore-domain potassium channel in Drosophila melanogaster,as an essential regulator for the proliferation of intestinal stem cells and malignant tumors,while dispensable for the normal development processes.Mechanistically,loss of sand elevates intracellular K+concentration,leading to growth inhibition.This phenotype is rescued by pharmacological reduction of intracellular K+levels using the K+ionophore.Conversely,overexpression of sand triggers stem cell death in most regions of the midgut,inhibits tumor growth,and induces a Notch loss-of-function phenotype in the posterior midgut.These effects are mediated predominantly via the induction of endoplasmic reticulum(ER)stress,as demonstrated by the complete rescue of phenotypes through the co-expression of Ire1 or Xbp1s.Additionally,human homologues of Sand demonstrated similar ER stress-inducing capabilities,suggesting an evolutionarily conserved relationship between this channel and ER stress.Together,our findings identify Sand as a shared regulatory node that governs Drosophila adult stem cell dynamics and tumorigenesis through bioelectric homeostasis,and reveal a link between the two-pore potassium channel and ER stress signaling.展开更多
Since the first electron micrograph of“lace-like structures”over 75 years ago,the endoplasmic reticulum(ER)is now viewed as a highly dynamic,constantly remodeling,continuous network of tubules and cisternae that pla...Since the first electron micrograph of“lace-like structures”over 75 years ago,the endoplasmic reticulum(ER)is now viewed as a highly dynamic,constantly remodeling,continuous network of tubules and cisternae that plays an important role in a broad range of cellular activities from calcium regulation to protein synthesis and trafficking.In neurons,the ER extends from the soma through the axon to presynaptic terminals,and throughout the dendritic arbor into as many as half of all postsynaptic dendritic spines at any given time(Falahati et al.,2022).展开更多
Objective:To assess the antitumor activity of the novel chitinase produced by fermented,isolated Trichoderma viride in a hepatocellular carcinoma(HCC)male rat model.Methods:Diethyl-nitrosamine induction combined with ...Objective:To assess the antitumor activity of the novel chitinase produced by fermented,isolated Trichoderma viride in a hepatocellular carcinoma(HCC)male rat model.Methods:Diethyl-nitrosamine induction combined with ionizing radiation exposure was used to establish the HCC rat model.All rats were divided into 4 groups:the control group,the chitinase group,the HCC group,and the HCC+chitinase group.The antiproliferative effect of chitinase was evaluated in human HCC cells.The effect of chitinase in vivo on oxidative stress,endoplasmic reticulum stress chaperones,autophagy markers,PI3K/AKT/mTOR,AMPK pathway expression,and apoptotic indicators was determined and confirmed by histological examination.Results:Chitinase significantly inhibited the viabilities of HepG2 cells.Moreover,in the Wistar male rat model of HCC,chitinase decreased ATP levels,modulated endoplasmic reticulum stress,mediated autophagy factors,and promoted apoptosis.Conclusions:Chitinase might play a role in the apoptosis as well as autophagy pathways and may act as a potential tumor suppressor.展开更多
基金The authors would like to thank the reviewers for their de-tailed reviews and constructive comments, which have helped improve the quality of this paper. This work was supported by the National Natural Science Foundation of China under Grant No. 61101107 the Scientific Research and Innovation Plan for the Youth of BUPT under Grant No. 2011RC0305 the National International Science and Technology Cooperation Project under Grant No. 2010DFA11320.
文摘In order to save energy and make more efficient use of wireless channel, this article puts forward an energy saving cooperative relaying scheme which actuates the cooperative transmis- sion only when the feedback from the destination indicates failure of the direct transmission. The proposed scheme selects the optimal relay and its corresponding transmission power in each time slot based on channel condition and residual ener- gy with the objective of minimizing energy con- sumption and extending network lifetime. In the study, the f＇mite-state Markov channel model is used to characterize the correlation structure of channel fading in wireless networks, and the pro- cedure of relay selection and transmission power decision is formulated as a M arkov decision process. Numerical and simulation results show that the proposed scheme consumes less energy and prolongs the network lifetime.
基金ACKNOWLEDGEMENT This work was partially supported by the Na- tional Natural Science Foundation of China under Grant No. 61071127 and the Science and Technology Department of Zhejiang Pro- vince under Grants No. 2012C01036-1, No. 2011R10035.
文摘Cooperative spectrum sensing in cog- nitive radio is investigated to improve the det- ection performance of Primary User （PU）. Meanwhile, cluster-based hierarchical coop- eration is introduced for reducing the overhead as well as maintaining a certain level of sens- ing performance. However, in existing hierar- chically cooperative spectrum sensing algo- rithms, the robustness problem of the system is seldom considered. In this paper, we pro- pose a reputation-based hierarchically coop- erative spectrum sensing scheme in Cognitive Radio Networks （CRNs）. Before spectrum sensing, clusters are grouped based on the location correlation coefficients of Secondary Users （SUs）. In the proposed scheme, there are two levels of cooperation, the first one is performed within a cluster and the second one is carried out among clusters. With the reputa- tion mechanism and modified MAJORITY rule in the second level cooperation, the pro- posed scheme can not only relieve the influ- ence of the shadowing, but also eliminate the impact of the PU emulation attack on a rela- tively large scale. Simulation results show that, in the scenarios with deep-shadowing or mul- tiple attacked SUs, our proposed scheme ach- ieves a better tradeoff between the system robustness and the energy saving compared with those conventionally cooperative sensing schemes.
文摘Genotype of IgH, TCRγ and TCR δ gene rearrangement in 42 cases of malignant lymphoproliferative disorders were studied by using polymerase chain reaction (PCR) technique. The results suggested that among the 23 cases, in which malignant cells expressed B-lineage cell surface markers, 20 showed IgH gene rearrangement and 11 had TCRγ gene rearrangement and / or TCRδ gene deletion. All the 11 cases expressed T-lineage cell differentiation antigens were found to have TCRγand TCRδ gene rearrangement or deletion and only one had IgH gene rearrangement. Double rearrangements of IgH and TCRγ genes were detected in all the 3 cases of T and B double-phenotype ALL. In the cases malignant cells did not express any lineage specific antigens while 4/5 had TCRγ gene rearrangement but all failed in IgH gene rearrangement. The relation of cellular differentiation origin and rearrangement of antigen receptor genes with clinical manifestations was discussed.
文摘The classification of lung nodules is a challenging problem as the visual analysis of the nodules and non-nodules revealed homogenous textural patterns.In this work,an Auxiliary Classifier(AC)-Generative Adversarial Network(GAN)based Lung Cancer Classification(LCC)system is developed.The pro-posed AC-GAN-LCC system consists of three modules;preprocessing,Lungs Region Detection(LRD),and AC-GAN classification.A Wienerfilter is employed in the preprocessing module to remove the Gaussian noise.In the LRD module,only the lung regions(left and right lungs)are detected using itera-tive thresholding and morphological operations.In order to extract the lung region only,floodfilling and background subtraction.The detected lung regions are fed to the AC-GAN classifier to detect the nodules.It classifies the nodules into one of the two classes,i.e.,binary classification(such as nodules or non-nodules).The AC-GAN is the extended version of the conditional GAN that predicts the label of a given image.Three different optimization techniques,adaptive gradient optimi-zation,root mean square propagation optimization,and Adam optimization are employed for optimizing the AC-GAN architecture.The proposed AC-GAN-LCC system is evaluated on the Lung Image Database Consortium(LIDC)data-base Computed Tomography(CT)scan images.The proposed AC-GAN-LCC system classifies∼15000 CT slices(7310 non-nodules and 7685 nodules).It pro-vides an overall accuracy of 98.8%on the LIDC database using Adam optimiza-tion by a 10-fold cross-validation approach.
文摘In the field of L2 （second language） reading, scholars generally agree that ER （extensive reading） improves L2 learners＇ reading speed and comprehension and enriches their L2 vocabulary （Grabe ＆ Stoller, 1997）. This teacher-inquiry type of paper presents a practical suggestion for supplementing ER activity with the element of CL （cooperative learning）. ER, theoretically speaking, focuses on the solitary task of silent reading. The CL technique used in this study was a book-talk activity. Forty-five freshmen from a course of children and young adult literatures were required to read at least 20 English books throughout a semester. CL was added to facilitate students＇ ER in young adult literature. After a semester, short-answer questions were asked regarding students＇ comments on ER as well as CL. Students overall agreed that when ER is supplemented with CL, reading in an L2 seems to be less intimidating.
基金Supported by the National Natural Science Foundation of China under Grant Nos 50672087 and 60778039, the National Basic Research Programme of China under Grant No 2006CB806007, the National High-Tech Research and Development Programme of China under Grant No 2006AA03Z304, and the Programme for Changjiang Scholars and Innovative Research Team in University （IRT0651）.
文摘We report on cooperative quantum cutting in Tb^3＋- Yb^3＋ codoped glass ceramics. Precipitation of BaF2 nanocrystals is confirmed by XRD and HRTEM analysis. Near-infrared emission due to transition of Yb^3＋ ions under 485 nm excitation indicates cooperative energy transfer from Tb^3＋ to Yb^3＋. The quantum efficiency of this process reaches 145%. The realization of quantum cutting in glass ceramics may have promising applications in solar cells.
基金supported by the National Natural Science Foundation of China to L.H.(32470754 and 32070750)to X.M.(32170824 and 32322027)HRHl program of Westlake Laboratory of Life Sciences and Biomedicine to X.M.(1011103360222B1).
文摘Potassium channels regulate diverse biological processes,ranging from cell proliferation to immune responses.However,the functions of potassium homeostasis and its regulatory mechanisms in adult stem cells and tumors remain poorly characterized.Here,we identify Sandman(Sand),a two-pore-domain potassium channel in Drosophila melanogaster,as an essential regulator for the proliferation of intestinal stem cells and malignant tumors,while dispensable for the normal development processes.Mechanistically,loss of sand elevates intracellular K+concentration,leading to growth inhibition.This phenotype is rescued by pharmacological reduction of intracellular K+levels using the K+ionophore.Conversely,overexpression of sand triggers stem cell death in most regions of the midgut,inhibits tumor growth,and induces a Notch loss-of-function phenotype in the posterior midgut.These effects are mediated predominantly via the induction of endoplasmic reticulum(ER)stress,as demonstrated by the complete rescue of phenotypes through the co-expression of Ire1 or Xbp1s.Additionally,human homologues of Sand demonstrated similar ER stress-inducing capabilities,suggesting an evolutionarily conserved relationship between this channel and ER stress.Together,our findings identify Sand as a shared regulatory node that governs Drosophila adult stem cell dynamics and tumorigenesis through bioelectric homeostasis,and reveal a link between the two-pore potassium channel and ER stress signaling.
基金supported by AHA Career Development Award 938683 (to PJD)NIH grant R01MH123700 (to MLD)
文摘Since the first electron micrograph of“lace-like structures”over 75 years ago,the endoplasmic reticulum(ER)is now viewed as a highly dynamic,constantly remodeling,continuous network of tubules and cisternae that plays an important role in a broad range of cellular activities from calcium regulation to protein synthesis and trafficking.In neurons,the ER extends from the soma through the axon to presynaptic terminals,and throughout the dendritic arbor into as many as half of all postsynaptic dendritic spines at any given time(Falahati et al.,2022).
文摘Objective:To assess the antitumor activity of the novel chitinase produced by fermented,isolated Trichoderma viride in a hepatocellular carcinoma(HCC)male rat model.Methods:Diethyl-nitrosamine induction combined with ionizing radiation exposure was used to establish the HCC rat model.All rats were divided into 4 groups:the control group,the chitinase group,the HCC group,and the HCC+chitinase group.The antiproliferative effect of chitinase was evaluated in human HCC cells.The effect of chitinase in vivo on oxidative stress,endoplasmic reticulum stress chaperones,autophagy markers,PI3K/AKT/mTOR,AMPK pathway expression,and apoptotic indicators was determined and confirmed by histological examination.Results:Chitinase significantly inhibited the viabilities of HepG2 cells.Moreover,in the Wistar male rat model of HCC,chitinase decreased ATP levels,modulated endoplasmic reticulum stress,mediated autophagy factors,and promoted apoptosis.Conclusions:Chitinase might play a role in the apoptosis as well as autophagy pathways and may act as a potential tumor suppressor.
