Metastasis is the hallmark of cancer that is responsible for the greatest number of cancer-related deaths.Yet,it remains poorly understood.The continuous evolution of cancer biology research and the emergence of new p...Metastasis is the hallmark of cancer that is responsible for the greatest number of cancer-related deaths.Yet,it remains poorly understood.The continuous evolution of cancer biology research and the emergence of new paradigms in the study of metastasis have revealed some of the molecular underpinnings of this dissemination process.The invading tumor cell,on its way to the target site,interacts with other proteins and cells.Recognition of these interactions improved the understanding of some of the biological principles of the metastatic cell that govern its mobility and plasticity.Communication with the tumor microenvironment allows invading cancer cells to overcome stromal challenges,settle,and colonize.These characteristics of cancer cells are driven by genetic and epigenetic modifications within the tumor cell itself and its microenvironment.Establishing the biological mechanisms of the metastatic process is crucial in finding open therapeutic windows for successful interventions.In this review,the authors explore the recent advancements in the field of metastasis and highlight the latest insights that contribute to shaping this hallmark of cancer.展开更多
In this paper,we propose enhancements to Beetle Antennae search(BAS)algorithm,called BAS-ADAIVL to smoothen the convergence behavior and avoid trapping in localminima for a highly noin-convex objective function.We ach...In this paper,we propose enhancements to Beetle Antennae search(BAS)algorithm,called BAS-ADAIVL to smoothen the convergence behavior and avoid trapping in localminima for a highly noin-convex objective function.We achieve this by adaptively adjusting the step-size in each iteration using the adaptive moment estimation(ADAM)update rule.The proposed algorithm also increases the convergence rate in a narrow valley.A key feature of the ADAM update rule is the ability to adjust the step-size for each dimension separately instead of using the same step-size.Since ADAM is traditionally used with gradient-based optimization algorithms,therefore we first propose a gradient estimation model without the need to differentiate the objective function.Resultantly,it demonstrates excellent performance and fast convergence rate in searching for the optimum of noin-convex functions.The efficiency of the proposed algorithm was tested on three different benchmark problems,including the training of a high-dimensional neural network.The performance is compared with particle swarm optimizer(PSO)and the original BAS algorithm.展开更多
Acute variceal hemorrhage,a life-threatening condition that requires a multidisciplinary approach for effective therapy,is defined as visible bleeding from an esophageal or gastric varix at the time of endoscopy,the p...Acute variceal hemorrhage,a life-threatening condition that requires a multidisciplinary approach for effective therapy,is defined as visible bleeding from an esophageal or gastric varix at the time of endoscopy,the presence of large esophageal varices with recent stigmata of bleeding,or fresh blood visible in the stomach with no other source of bleeding identified.Transfusion of blood products,pharmacological treatments and early endoscopic therapy are often effective;however,if primary hemostasis cannot be obtained or if uncontrollable early rebleeding occurs,transjugular intrahepatic portosystemic shunt(TIPS)is recommended as rescue treatment.The TIPS represents a major advance in the treatment of complications of portal hypertension.Acute variceal hemorrhage that is poorly controlled with endoscopic therapy is generally well controlled with TIPS,which has a 90%to 100%success rate.However,TIPS is associated with a mortality of 30%to 50%in such a setting.Emergency TIPS should be considered early in patients with refractory variceal bleeding once medical treatment and endoscopic sclerotherapy failure,before the clinical condition worsens.Furthermore,admission to specialized centers is mandatory in such a setting and regional protocols are essential to be organized effectively.This review article discusses initial management and then focuses on the specific role of TIPS as a primary therapy to control acute variceal hemorrhage,particularly as a rescue therapy following failure of endoscopic approaches.展开更多
Colorectal cancer (CRC) is the third most common malignancy and the third leading cause of cancer related deaths in the United States. Almost 90% of the patients diagnosed with CRC die due to metastases. MicroRNAs (mi...Colorectal cancer (CRC) is the third most common malignancy and the third leading cause of cancer related deaths in the United States. Almost 90% of the patients diagnosed with CRC die due to metastases. MicroRNAs (miRNAs) are evolutionarily conserved molecules that modulate the expression of their target genes post-transcriptionally, and they may participate in various physiological and pathological processes including CRC metastasis by influencing various factors in the human body. Recently, the role miRNAs play throughout the CRC metastatic cascade has gain attention. Many studies have been published to link them with CRC metastasis. In this review, we will briefly discuss metastatic steps in the light of miRNAs, along with their target genes. We will discuss how the aberration in the expression of miRNAs leads to the formation of CRC by effecting the regulation of their target genes. As miRNAs are being exploited for diagnosis, prognosis, and monitoring of cancer and other diseases, their high tissue specificity and critical role in oncogenesis make them new biomarkers for the diagnosis and classification of cancer as well as for predicting patients’ outcome. MiRNA signatures have been identified for many human tumors including CRC, and miRNA-based therapies to treat cancer have been emphasized lately. These will also be discussed in this review.展开更多
Sepsis and septic shock are life threatening condition associated with high mortality rate in critically-ill patients. This high mortality is mainly related to the inadequacy between oxygen delivery and cellular deman...Sepsis and septic shock are life threatening condition associated with high mortality rate in critically-ill patients. This high mortality is mainly related to the inadequacy between oxygen delivery and cellular demand leading to the onset of multiorgan dysfunction. Whether this multiorgan failure affect the pancreas is not fully investigated. In fact, pancreatic injury may occur because of ischemia, overwhelming inflammatory response, oxidative stress, cellular apoptosis and/or metabolic derangement. Increased serum amylase and/or lipase levels are common in patients with septic shock. However, imaging test rarely reveal significant pancreatic damage. Whether pancreatic dysfunction does affect the prognosis of patients with septic shock or not is still a matter of debate. In fact, only few studies with limited sample size assessed the clinical relevance of the pancreatic injury in this group of patients. In this review, we aimed to describe the epidemiology and the physiopathology of pancreatic injury in septic shock patients, to clarify whether it requires specific management and to assess its prognostic value. Our main finding is that pancreatic injury does not significantly affect the outcome in septic shock patients. Hence, increased serum pancreatic enzymes without clinical features of acute pancreatitis do not require further imaging investigations and specific therapeutic intervention.展开更多
The Systemic Approach in Teaching and Learning Chemistry(SATLC)was established in 1997[1-3].Our interest in develo—ping the SATL strategy arose from the recognition of the increasing globalization of a wide spectrum ...The Systemic Approach in Teaching and Learning Chemistry(SATLC)was established in 1997[1-3].Our interest in develo—ping the SATL strategy arose from the recognition of the increasing globalization of a wide spectrum of human activities such as economics,media,politics,and entertainment.Systemics is our attempt to provide the student with a global view of his/her studies of chemistry.展开更多
In this paper, we elaborate a new strategy based on cooperative game theory models to encourage and manage the interactions in a MicroGrid network. The proposed strategy optimizes the cooperation and the energy exchan...In this paper, we elaborate a new strategy based on cooperative game theory models to encourage and manage the interactions in a MicroGrid network. The proposed strategy optimizes the cooperation and the energy exchange in a distributed μGrid network. The strategy consists of a two stage algorithm: Coalition formation algorithm which was specifically created to approximate the optimal set of coalitions that return considerable savings. And the Matching game to manage the energy exchange inside each coalition. The performance of our strategy was verified through simulations. These latter show that the losses can be considerably decreased by the use of the proposed strategy: the rate of the loss reduction can reach up to 20% if the two stages are applied on the network. Moreover, the strategy proved to have a fast convergence which makes it operational for real implemented networks.展开更多
Herbicide use is rising globally to enhance food production,causing harm to environment and the ecosystem.Precision agriculture suggests variable-rate herbicide application based on weed densities to mitigate adverse ...Herbicide use is rising globally to enhance food production,causing harm to environment and the ecosystem.Precision agriculture suggests variable-rate herbicide application based on weed densities to mitigate adverse effects of herbicides.Accurate weed density estimation using advanced computer vision techniques like deep learning requires large labelled agriculture data.Labelling large agriculture data at pixel level is a time-consuming and tedious job.In this paper,a methodology is developed to accelerate manual labelling of pixels using a two-step procedure.In the first step,the background and foreground are segmented using maximum likelihood classification,and in the second step,the weed pixels are manually labelled.Such labelled data is used to train semantic segmentation models,which classify crop and background pixels as one class,and all other vegetation as the second class.This paper evaluates the proposed methodology on high-resolution colour images of canola fields and makes performance comparison of deep learning meta-architectures like SegNet and UNET and encoder blocks like VGG16 and ResNet-50.ResNet-50 based SegNet model has shown the best results with mean intersection over union value of 0.8288 and frequency weighted intersection over union value of 0.9869.展开更多
AIM： To study the prevalence and clinical effects of occult HBV infection in haemodialysis patients with chronic HCV.METHODS： Fifty chronic hemodialysis patients with negative HbsAg, and positive anti-HCV were inclu...AIM： To study the prevalence and clinical effects of occult HBV infection in haemodialysis patients with chronic HCV.METHODS： Fifty chronic hemodialysis patients with negative HbsAg, and positive anti-HCV were included in the study. These patients were divided into two groups： HCV-RNA positive and HCV-RNA negative, based on the results of HCV-RNA PCR. HBV-DNA was studied using the PCR method in both groups.RESULTS： None of the 22 HCV-RNA positive patients and 28 HCV-RNA negative patients revealed HBV-DNA in serum by PCR method. The average age was 47.2±17.0 in the HCV-RNA positive group and 39.6±15.6 in the HCV-RNA negative group.CONCLUSION： The prevalence of occult HBV infection is not high in haemodialysis patients with chronic HCV in our region. This result of our study has to be evaluated in consideration of the interaction between HBsAg positivity （8%-10%） and frequency of HBV mutants in our region.展开更多
This paper presents an experimental study to compare the performance of model-free control strategies for pneumatic soft robots.Fabricated using soft materials,soft robots have gained much attention in academia and in...This paper presents an experimental study to compare the performance of model-free control strategies for pneumatic soft robots.Fabricated using soft materials,soft robots have gained much attention in academia and industry during recent years because of their inherent safety in human interaction.However,due to structural flexibility and compliance,mathematical models for these soft robots are nonlinear with an infinite degree of freedom(DOF).Therefore,accurate position(or orientation)control and optimization of their dynamic response remains a challenging task.Most existing soft robots currently employed in industrial and rehabilitation applications use model-free control algorithms such as PID.However,to the best of our knowledge,there has been no systematic study on the comparative performance of model-free control algorithms and their ability to optimize dynamic response,i.e.,reduce overshoot and settling time.In this paper,we present comparative performance of several variants of model-free PID-controllers based on extensive experimental results.Additionally,most of the existing work on modelfree control in pneumatic soft-robotic literature use manually tuned parameters,which is a time-consuming,labor-intensive task.We present a heuristic-based coordinate descent algorithm to tune the controller parameter automatically.We presented results for both manual tuning and automatic tuning using the Ziegler-Nichols method and proposed algorithm,respectively.We then used experimental results to statistically demonstrate that the presented automatic tuning algorithm results in high accuracy.The experiment results show that for soft robots,the PID-controller essentially reduces to the PI controller.This behavior was observed in both manual and automatic tuning experiments;we also discussed a rationale for removing the derivative term.展开更多
Mild traumatic brain injury（TBI）, also called concussion, initiates sequelae leading to motor deficits, cognitive impairments and subtly compromised neurobehaviors. While the acute phase of TBI is associated with ne...Mild traumatic brain injury（TBI）, also called concussion, initiates sequelae leading to motor deficits, cognitive impairments and subtly compromised neurobehaviors. While the acute phase of TBI is associated with neuroinflammation and nitroxidative burst, the chronic phase shows a lack of stimulation of the neurorepair process and regeneration. The deficiency of nitric oxide（NO）, the consequent disturbed NO metabolome, and imbalanced mechanisms of S-nitrosylation are implicated in blocking the mechanisms of neurorepair processes and functional recovery in the both phases. Hypoxia inducible factor-1 alpha（HIF-1α）, a master regulator of hypoxia/ischemia, stimulates the process of neurorepair and thus aids in functional recovery after brain trauma. The activity of HIF-1α is regulated by NO via the mechanism of S-nitrosylation of HIF-1α. S-nitrosylation is dynamically regulated by NO metabolites such as S-nitrosoglutathione（GSNO） and peroxynitrite. GSNO stabilizes, and peroxynitrite destabilizes HIF-1α. Exogenously administered GSNO was found not only to stabilize HIF-1α and to induce HIF-1α-dependent genes but also to stimulate the regeneration process and to aid in functional recovery in TBI animals.展开更多
The discovery of microRNAs （miRNAs） is one of tbe most significant breakthroughs in recent decades, miRNAs are a class of small, endogenous, non-coding RNAs （19-24 nt） that negatively regulate the expression of ta...The discovery of microRNAs （miRNAs） is one of tbe most significant breakthroughs in recent decades, miRNAs are a class of small, endogenous, non-coding RNAs （19-24 nt） that negatively regulate the expression of target genes by binding to their 3＇ untranslated region and are involved in various biological processes. Three main approaches that are globally used for the detection of miRNA include direct cloning, forward genetics and computational approaches using bioinformatics.展开更多
The paper investigates the powerful of hybridizing two computational intelligence methods viz., Gray Wolf Optimization (GWO) and Artificial Neural Networks (ANN) for prediction of heart disease. Gray wolf optimization...The paper investigates the powerful of hybridizing two computational intelligence methods viz., Gray Wolf Optimization (GWO) and Artificial Neural Networks (ANN) for prediction of heart disease. Gray wolf optimization is a global search method while gradient-based back propagation method is a local search one. The proposed algorithm implies the ability of ANN to find a relationship between the input and the output variables while the stochastic search ability of GWO is used for finding the initial optimal weights and biases of the ANN to reduce the probability of ANN getting stuck at local minima and slowly converging to global optimum. For evaluation purpose, the performance of hybrid model (ANN-GWO) was compared with standard back-propagation neural network (BPNN) using Root Mean Square Error (RMSE). The results demonstrate that the proposed model increases the convergence speed and the accuracy of prediction.展开更多
The lithium potential in the Aïr massif is represented by mineral index of spodumene pegmatites and, lepidolite pegmatites. The mineral deposits of lithium occur in cluster or veins that cut the host rock or are ...The lithium potential in the Aïr massif is represented by mineral index of spodumene pegmatites and, lepidolite pegmatites. The mineral deposits of lithium occur in cluster or veins that cut the host rock or are located near the contact between the greenstone belt and granitic massif. The evidence of lithium is in the form of clusters or disseminated and stockwerk. Mineralogical characteristics show similarities between the Air Massif pegmatites and indicate the same homogenous source during the magma-generation process. The pegmatite rocks attracted the attention due to their wide exposure and composition, well appearance, and economically hosting of significant rare earth metals such as Sn and W. The mineralogical and petrographical investigations on the eight pegmatites rocks samples observed have a relative similarity, while a little difference in the shapes attributed to the ratio in the pegmatite rocks of the minerals. The occurrence of the kink band indicates the influence of the tectonic processes which affected the Aïr massif after the emplacement of late magmatic or post-magmatic pegmatites by injection into fractured rocks in the upper part of the crust. The Air Massif pegmatite has higher concentrations Li and of all trace elements except Hf and occasionally Zr, Ti, Sn and Mg of for the economic exploration.展开更多
Background: Confusion often arises in caring for diabetic foot infections and ulcers, especially with antimicrobials;we aim to shed light on this entity and alert healthcare workers to its stewardship. Methods: Record...Background: Confusion often arises in caring for diabetic foot infections and ulcers, especially with antimicrobials;we aim to shed light on this entity and alert healthcare workers to its stewardship. Methods: Records were reviewed between February 2016 and September 2023. Data for patients diagnosed with diabetes and foot ulcers, infected or not, were examined following ICD 9 search terms. Records for patients were included if they were prediabetic/diabetic adults with foot ulcers, more than 18 years old, and on antidiabetic treatment. Patients were excluded if they insulin resistant, with normal HgbA1c levels, wheel-chair dependent, bed-bound, non-diabetic patients, diabetic patients who had vascular lower limb surgery earlier to ulcers, diabetic patients who had aortocoronary bypass, deep venous thrombosis within six months, malignancy, and severe clinical depression. A modified IWGDF/IDSA guidelines definitions for DFI and DFU was considered. Statistical analysis was done using R programming. Statistical methods were employed as appropriate, and a significant P-value was considered for P Results: Most characteristics were well balanced between DFI and DFU, on imaging osteomyelitis and tissue swelling were significantly more in DFI. Endovascular radiological procedures showed angiograms to be considerably more in DFI, while angioplasty was more in DFU, in addition to smoking. Bacteremia was uncommon, and swab cultures were mostly polymicrobial in both ulcers;no clear association with blood bacteria was detected with the polymicrobial growth, though few were concordant. Antimicrobials prescribed for both ulcers were not statistically different except for carbapenems, which were more in DFI (P Conclusion: Attention should be paid to best practices while caring for diabetic ulcers. These include swab culture interpretations, the use of antimicrobials, and plan management according to DFI or DFU to utilize either local care or combination with antimicrobials.展开更多
Background: Cut-throat injury is a potentially fatal condition that may be associated with serious morbidity and mortality. The neck region is particularly at risk of serious injuries due to the location of vital stru...Background: Cut-throat injury is a potentially fatal condition that may be associated with serious morbidity and mortality. The neck region is particularly at risk of serious injuries due to the location of vital structures, including nerves, viscera, and major vessels. Although cut-throat injury is said to be rare in children, its occurrence has been reported in some series. Management of this condition requires a multidisciplinary approach for a better outcome. Aim: The aim of this report is to highlight the successful management of an alarming case of severe cut-throat injury with associated laryngeal injury in a child. Case presentation: A 12-year-old boy presented with a cut-throat following an assault by an unknown person. Examination revealed an acutely ill child, conscious but pale. He sustained a deep transverse laceration that transected the thyroid cartilage, exposing the laryngeal cavity. An assessment of Zone II penetrating neck injury was made. He was resuscitated, and had emergency neck exploration, tracheostomy, and repair of the injuries. The patient was followed up for 6 months, and had a good voice outcome, with no significant complication. Conclusion: Cut-throat injury is rare in children. But it is a potentially life-threatening condition. It is therefore important to recognize this entity and develop effective protocol of management in our environment.展开更多
文摘Metastasis is the hallmark of cancer that is responsible for the greatest number of cancer-related deaths.Yet,it remains poorly understood.The continuous evolution of cancer biology research and the emergence of new paradigms in the study of metastasis have revealed some of the molecular underpinnings of this dissemination process.The invading tumor cell,on its way to the target site,interacts with other proteins and cells.Recognition of these interactions improved the understanding of some of the biological principles of the metastatic cell that govern its mobility and plasticity.Communication with the tumor microenvironment allows invading cancer cells to overcome stromal challenges,settle,and colonize.These characteristics of cancer cells are driven by genetic and epigenetic modifications within the tumor cell itself and its microenvironment.Establishing the biological mechanisms of the metastatic process is crucial in finding open therapeutic windows for successful interventions.In this review,the authors explore the recent advancements in the field of metastasis and highlight the latest insights that contribute to shaping this hallmark of cancer.
文摘In this paper,we propose enhancements to Beetle Antennae search(BAS)algorithm,called BAS-ADAIVL to smoothen the convergence behavior and avoid trapping in localminima for a highly noin-convex objective function.We achieve this by adaptively adjusting the step-size in each iteration using the adaptive moment estimation(ADAM)update rule.The proposed algorithm also increases the convergence rate in a narrow valley.A key feature of the ADAM update rule is the ability to adjust the step-size for each dimension separately instead of using the same step-size.Since ADAM is traditionally used with gradient-based optimization algorithms,therefore we first propose a gradient estimation model without the need to differentiate the objective function.Resultantly,it demonstrates excellent performance and fast convergence rate in searching for the optimum of noin-convex functions.The efficiency of the proposed algorithm was tested on three different benchmark problems,including the training of a high-dimensional neural network.The performance is compared with particle swarm optimizer(PSO)and the original BAS algorithm.
文摘Acute variceal hemorrhage,a life-threatening condition that requires a multidisciplinary approach for effective therapy,is defined as visible bleeding from an esophageal or gastric varix at the time of endoscopy,the presence of large esophageal varices with recent stigmata of bleeding,or fresh blood visible in the stomach with no other source of bleeding identified.Transfusion of blood products,pharmacological treatments and early endoscopic therapy are often effective;however,if primary hemostasis cannot be obtained or if uncontrollable early rebleeding occurs,transjugular intrahepatic portosystemic shunt(TIPS)is recommended as rescue treatment.The TIPS represents a major advance in the treatment of complications of portal hypertension.Acute variceal hemorrhage that is poorly controlled with endoscopic therapy is generally well controlled with TIPS,which has a 90%to 100%success rate.However,TIPS is associated with a mortality of 30%to 50%in such a setting.Emergency TIPS should be considered early in patients with refractory variceal bleeding once medical treatment and endoscopic sclerotherapy failure,before the clinical condition worsens.Furthermore,admission to specialized centers is mandatory in such a setting and regional protocols are essential to be organized effectively.This review article discusses initial management and then focuses on the specific role of TIPS as a primary therapy to control acute variceal hemorrhage,particularly as a rescue therapy following failure of endoscopic approaches.
文摘Colorectal cancer (CRC) is the third most common malignancy and the third leading cause of cancer related deaths in the United States. Almost 90% of the patients diagnosed with CRC die due to metastases. MicroRNAs (miRNAs) are evolutionarily conserved molecules that modulate the expression of their target genes post-transcriptionally, and they may participate in various physiological and pathological processes including CRC metastasis by influencing various factors in the human body. Recently, the role miRNAs play throughout the CRC metastatic cascade has gain attention. Many studies have been published to link them with CRC metastasis. In this review, we will briefly discuss metastatic steps in the light of miRNAs, along with their target genes. We will discuss how the aberration in the expression of miRNAs leads to the formation of CRC by effecting the regulation of their target genes. As miRNAs are being exploited for diagnosis, prognosis, and monitoring of cancer and other diseases, their high tissue specificity and critical role in oncogenesis make them new biomarkers for the diagnosis and classification of cancer as well as for predicting patients’ outcome. MiRNA signatures have been identified for many human tumors including CRC, and miRNA-based therapies to treat cancer have been emphasized lately. These will also be discussed in this review.
文摘Sepsis and septic shock are life threatening condition associated with high mortality rate in critically-ill patients. This high mortality is mainly related to the inadequacy between oxygen delivery and cellular demand leading to the onset of multiorgan dysfunction. Whether this multiorgan failure affect the pancreas is not fully investigated. In fact, pancreatic injury may occur because of ischemia, overwhelming inflammatory response, oxidative stress, cellular apoptosis and/or metabolic derangement. Increased serum amylase and/or lipase levels are common in patients with septic shock. However, imaging test rarely reveal significant pancreatic damage. Whether pancreatic dysfunction does affect the prognosis of patients with septic shock or not is still a matter of debate. In fact, only few studies with limited sample size assessed the clinical relevance of the pancreatic injury in this group of patients. In this review, we aimed to describe the epidemiology and the physiopathology of pancreatic injury in septic shock patients, to clarify whether it requires specific management and to assess its prognostic value. Our main finding is that pancreatic injury does not significantly affect the outcome in septic shock patients. Hence, increased serum pancreatic enzymes without clinical features of acute pancreatitis do not require further imaging investigations and specific therapeutic intervention.
文摘The Systemic Approach in Teaching and Learning Chemistry(SATLC)was established in 1997[1-3].Our interest in develo—ping the SATL strategy arose from the recognition of the increasing globalization of a wide spectrum of human activities such as economics,media,politics,and entertainment.Systemics is our attempt to provide the student with a global view of his/her studies of chemistry.
文摘In this paper, we elaborate a new strategy based on cooperative game theory models to encourage and manage the interactions in a MicroGrid network. The proposed strategy optimizes the cooperation and the energy exchange in a distributed μGrid network. The strategy consists of a two stage algorithm: Coalition formation algorithm which was specifically created to approximate the optimal set of coalitions that return considerable savings. And the Matching game to manage the energy exchange inside each coalition. The performance of our strategy was verified through simulations. These latter show that the losses can be considerably decreased by the use of the proposed strategy: the rate of the loss reduction can reach up to 20% if the two stages are applied on the network. Moreover, the strategy proved to have a fast convergence which makes it operational for real implemented networks.
文摘Herbicide use is rising globally to enhance food production,causing harm to environment and the ecosystem.Precision agriculture suggests variable-rate herbicide application based on weed densities to mitigate adverse effects of herbicides.Accurate weed density estimation using advanced computer vision techniques like deep learning requires large labelled agriculture data.Labelling large agriculture data at pixel level is a time-consuming and tedious job.In this paper,a methodology is developed to accelerate manual labelling of pixels using a two-step procedure.In the first step,the background and foreground are segmented using maximum likelihood classification,and in the second step,the weed pixels are manually labelled.Such labelled data is used to train semantic segmentation models,which classify crop and background pixels as one class,and all other vegetation as the second class.This paper evaluates the proposed methodology on high-resolution colour images of canola fields and makes performance comparison of deep learning meta-architectures like SegNet and UNET and encoder blocks like VGG16 and ResNet-50.ResNet-50 based SegNet model has shown the best results with mean intersection over union value of 0.8288 and frequency weighted intersection over union value of 0.9869.
文摘AIM： To study the prevalence and clinical effects of occult HBV infection in haemodialysis patients with chronic HCV.METHODS： Fifty chronic hemodialysis patients with negative HbsAg, and positive anti-HCV were included in the study. These patients were divided into two groups： HCV-RNA positive and HCV-RNA negative, based on the results of HCV-RNA PCR. HBV-DNA was studied using the PCR method in both groups.RESULTS： None of the 22 HCV-RNA positive patients and 28 HCV-RNA negative patients revealed HBV-DNA in serum by PCR method. The average age was 47.2±17.0 in the HCV-RNA positive group and 39.6±15.6 in the HCV-RNA negative group.CONCLUSION： The prevalence of occult HBV infection is not high in haemodialysis patients with chronic HCV in our region. This result of our study has to be evaluated in consideration of the interaction between HBsAg positivity （8%-10%） and frequency of HBV mutants in our region.
文摘This paper presents an experimental study to compare the performance of model-free control strategies for pneumatic soft robots.Fabricated using soft materials,soft robots have gained much attention in academia and industry during recent years because of their inherent safety in human interaction.However,due to structural flexibility and compliance,mathematical models for these soft robots are nonlinear with an infinite degree of freedom(DOF).Therefore,accurate position(or orientation)control and optimization of their dynamic response remains a challenging task.Most existing soft robots currently employed in industrial and rehabilitation applications use model-free control algorithms such as PID.However,to the best of our knowledge,there has been no systematic study on the comparative performance of model-free control algorithms and their ability to optimize dynamic response,i.e.,reduce overshoot and settling time.In this paper,we present comparative performance of several variants of model-free PID-controllers based on extensive experimental results.Additionally,most of the existing work on modelfree control in pneumatic soft-robotic literature use manually tuned parameters,which is a time-consuming,labor-intensive task.We present a heuristic-based coordinate descent algorithm to tune the controller parameter automatically.We presented results for both manual tuning and automatic tuning using the Ziegler-Nichols method and proposed algorithm,respectively.We then used experimental results to statistically demonstrate that the presented automatic tuning algorithm results in high accuracy.The experiment results show that for soft robots,the PID-controller essentially reduces to the PI controller.This behavior was observed in both manual and automatic tuning experiments;we also discussed a rationale for removing the derivative term.
基金supported by grants from VA merit awards(BX3401 and RX2090)
文摘Mild traumatic brain injury（TBI）, also called concussion, initiates sequelae leading to motor deficits, cognitive impairments and subtly compromised neurobehaviors. While the acute phase of TBI is associated with neuroinflammation and nitroxidative burst, the chronic phase shows a lack of stimulation of the neurorepair process and regeneration. The deficiency of nitric oxide（NO）, the consequent disturbed NO metabolome, and imbalanced mechanisms of S-nitrosylation are implicated in blocking the mechanisms of neurorepair processes and functional recovery in the both phases. Hypoxia inducible factor-1 alpha（HIF-1α）, a master regulator of hypoxia/ischemia, stimulates the process of neurorepair and thus aids in functional recovery after brain trauma. The activity of HIF-1α is regulated by NO via the mechanism of S-nitrosylation of HIF-1α. S-nitrosylation is dynamically regulated by NO metabolites such as S-nitrosoglutathione（GSNO） and peroxynitrite. GSNO stabilizes, and peroxynitrite destabilizes HIF-1α. Exogenously administered GSNO was found not only to stabilize HIF-1α and to induce HIF-1α-dependent genes but also to stimulate the regeneration process and to aid in functional recovery in TBI animals.
文摘The discovery of microRNAs （miRNAs） is one of tbe most significant breakthroughs in recent decades, miRNAs are a class of small, endogenous, non-coding RNAs （19-24 nt） that negatively regulate the expression of target genes by binding to their 3＇ untranslated region and are involved in various biological processes. Three main approaches that are globally used for the detection of miRNA include direct cloning, forward genetics and computational approaches using bioinformatics.
文摘The paper investigates the powerful of hybridizing two computational intelligence methods viz., Gray Wolf Optimization (GWO) and Artificial Neural Networks (ANN) for prediction of heart disease. Gray wolf optimization is a global search method while gradient-based back propagation method is a local search one. The proposed algorithm implies the ability of ANN to find a relationship between the input and the output variables while the stochastic search ability of GWO is used for finding the initial optimal weights and biases of the ANN to reduce the probability of ANN getting stuck at local minima and slowly converging to global optimum. For evaluation purpose, the performance of hybrid model (ANN-GWO) was compared with standard back-propagation neural network (BPNN) using Root Mean Square Error (RMSE). The results demonstrate that the proposed model increases the convergence speed and the accuracy of prediction.
文摘The lithium potential in the Aïr massif is represented by mineral index of spodumene pegmatites and, lepidolite pegmatites. The mineral deposits of lithium occur in cluster or veins that cut the host rock or are located near the contact between the greenstone belt and granitic massif. The evidence of lithium is in the form of clusters or disseminated and stockwerk. Mineralogical characteristics show similarities between the Air Massif pegmatites and indicate the same homogenous source during the magma-generation process. The pegmatite rocks attracted the attention due to their wide exposure and composition, well appearance, and economically hosting of significant rare earth metals such as Sn and W. The mineralogical and petrographical investigations on the eight pegmatites rocks samples observed have a relative similarity, while a little difference in the shapes attributed to the ratio in the pegmatite rocks of the minerals. The occurrence of the kink band indicates the influence of the tectonic processes which affected the Aïr massif after the emplacement of late magmatic or post-magmatic pegmatites by injection into fractured rocks in the upper part of the crust. The Air Massif pegmatite has higher concentrations Li and of all trace elements except Hf and occasionally Zr, Ti, Sn and Mg of for the economic exploration.
文摘Background: Confusion often arises in caring for diabetic foot infections and ulcers, especially with antimicrobials;we aim to shed light on this entity and alert healthcare workers to its stewardship. Methods: Records were reviewed between February 2016 and September 2023. Data for patients diagnosed with diabetes and foot ulcers, infected or not, were examined following ICD 9 search terms. Records for patients were included if they were prediabetic/diabetic adults with foot ulcers, more than 18 years old, and on antidiabetic treatment. Patients were excluded if they insulin resistant, with normal HgbA1c levels, wheel-chair dependent, bed-bound, non-diabetic patients, diabetic patients who had vascular lower limb surgery earlier to ulcers, diabetic patients who had aortocoronary bypass, deep venous thrombosis within six months, malignancy, and severe clinical depression. A modified IWGDF/IDSA guidelines definitions for DFI and DFU was considered. Statistical analysis was done using R programming. Statistical methods were employed as appropriate, and a significant P-value was considered for P Results: Most characteristics were well balanced between DFI and DFU, on imaging osteomyelitis and tissue swelling were significantly more in DFI. Endovascular radiological procedures showed angiograms to be considerably more in DFI, while angioplasty was more in DFU, in addition to smoking. Bacteremia was uncommon, and swab cultures were mostly polymicrobial in both ulcers;no clear association with blood bacteria was detected with the polymicrobial growth, though few were concordant. Antimicrobials prescribed for both ulcers were not statistically different except for carbapenems, which were more in DFI (P Conclusion: Attention should be paid to best practices while caring for diabetic ulcers. These include swab culture interpretations, the use of antimicrobials, and plan management according to DFI or DFU to utilize either local care or combination with antimicrobials.
文摘Background: Cut-throat injury is a potentially fatal condition that may be associated with serious morbidity and mortality. The neck region is particularly at risk of serious injuries due to the location of vital structures, including nerves, viscera, and major vessels. Although cut-throat injury is said to be rare in children, its occurrence has been reported in some series. Management of this condition requires a multidisciplinary approach for a better outcome. Aim: The aim of this report is to highlight the successful management of an alarming case of severe cut-throat injury with associated laryngeal injury in a child. Case presentation: A 12-year-old boy presented with a cut-throat following an assault by an unknown person. Examination revealed an acutely ill child, conscious but pale. He sustained a deep transverse laceration that transected the thyroid cartilage, exposing the laryngeal cavity. An assessment of Zone II penetrating neck injury was made. He was resuscitated, and had emergency neck exploration, tracheostomy, and repair of the injuries. The patient was followed up for 6 months, and had a good voice outcome, with no significant complication. Conclusion: Cut-throat injury is rare in children. But it is a potentially life-threatening condition. It is therefore important to recognize this entity and develop effective protocol of management in our environment.
