The shoreline is one of the rapidly changing landforms in coastal areas. They are the key element in coastal GIS and provide the most information on coastal land form dynamics. Therefore, accurate detection and freque...The shoreline is one of the rapidly changing landforms in coastal areas. They are the key element in coastal GIS and provide the most information on coastal land form dynamics. Therefore, accurate detection and frequent monitoring of shorelines is very essential to understand the coastal processes and dynamics of various coastal features. The present study is to investigate the shoreline changes along the coast between Kanyakumari and Tuticorin of south India (where hydrodynamic and morphologic changes occur continuously after the December 2004 tsunami) by using Digital Shoreline Analysis System (DSAS), an extension of ArcGIS. Multidate 1RS and Landsat Satellite data (1999, 2001, 2003, 2005, 2007, and 2009) are used to extract the shorelines. The data is processed by using the ERDAS IMAGINE 9.1 software and analyzed by ArcGIS 9.2 workstation. The rates of shoreline changes are estimated by three statistical methods, namely, End Point Rate (EPR), Linear Regression Rate (LRR), and Least Median of Squares (LMS) by using DSAS. The study reveals that most of the study area has undergoing erosion. Both natural and anthropogenic processes along the coast modify the shoreline configuration and control the erosion and accretion of the coastal zones. The coastal zones along the estuary have experienced accretion due to the littoral processes. The zones with headlands have more eroded than other zones along the study area. The study also shows that the coastal zones where sand is mined have relatively more rate of erosion than that of the other zones. Improper and unsustainable sand mining may also lead to severe erosion problem along this area. The shoreline change rates are altered by various geological processes along the coast. Thus, the present study implies that proper beach filling and nourishment projects should be made in the study area to save from hazards. It also indicates the advantage and suitability of DSAS to assess the shoreline changes compared with the traditional manual shoreline 展开更多
This paper is concerned with the exponential H_∞ filtering problem for a class of discrete-time switched neural networks with random time-varying delays based on the sojourn-probability-dependent method. Using the av...This paper is concerned with the exponential H_∞ filtering problem for a class of discrete-time switched neural networks with random time-varying delays based on the sojourn-probability-dependent method. Using the average dwell time approach together with the piecewise Lyapunov function technique, sufficient conditions are proposed to guarantee the exponential stability for the switched neural networks with random time-varying delays which are characterized by introducing a Bernoulli stochastic variable.Based on the derived H_∞ performance analysis results, the H_∞ filter design is formulated in terms of Linear Matrix Inequalities(LMIs). Finally, two numerical examples are presented to demonstrate the effectiveness of the proposed design procedure.展开更多
Applying indocyanine green(ICG)fluorescence in surgery has created a new dimension of navigation surgery to advance in various disciplines.The research in this field is nascent and fragmented,necessitating academic ef...Applying indocyanine green(ICG)fluorescence in surgery has created a new dimension of navigation surgery to advance in various disciplines.The research in this field is nascent and fragmented,necessitating academic efforts to gain a comprehensive understanding.The present review aims to integrate diverse perspectives and recent advances in its application in gastrointestinal surgery.The relevant articles were selected by using the appropriate keyword search in PubMed.The angiography and cholangiography property of ICG fluorescence is helpful in various hepatobiliary disorders.In gastroesophageal and colorectal surgery,the lymphangiography and angiography property of ICG is applied to evaluate bowel vascularity and guide lymphadenectomy.The lack of objective parameters to assess ICG fluorescence has been the primary limitation when ICG is used to evaluate bowel perfusion.The optimum dose and timing of ICG administration need to be standardized in some new application areas in gastrointestinal surgery.Binding tumor-specific ligands with fluorophores can potentially widen the fluorescence application to detect primary and metastatic gastrointestinal tumors.The narrative review outlines prior contributions,limitations,and research opportunities for future studies across gastrointestinal sub-specialty.The findings of the present review would be helpful for scholars and practitioners to explore and progress in this exciting domain of gastrointestinal surgery.展开更多
The preparation process of sodium molybdate has the disadvantages of high energy consumption,low thermal efficiency,and high raw material requirement of molybdenum trioxide,in order to realize the green and efficient ...The preparation process of sodium molybdate has the disadvantages of high energy consumption,low thermal efficiency,and high raw material requirement of molybdenum trioxide,in order to realize the green and efficient development of molybdenum concentrate resources,this paper proposes a new process for efficient recovery of molybdenum from molybdenum concentrate and preparation of sodium molybdate by microwave-enhanced roasting and alkali leaching.Thermodynamic analysis indicated the feasibility of oxidation roasting of molybdenum concentrate.The effects of roasting temperature,holding time,and power-to-mass ratio on the oxidation product and leaching product sodium molybdate (Na_(2)MoO_(4)·2H_(2)O) were investigated.Under the optimal process conditions:roasting temperature of 700℃,holding time of 110 min,and power-to-mass ratio of 110 W/g,the molybdenum state of existence was converted from MoS_(2) to Mo O3.The process of preparing sodium molybdate by alkali leaching of molybdenum calcine was investigated,the optimal leaching conditions include a solution concentration of 2.5 mol/L,a liquid-to-solid ratio of 2 mL/g,a leaching temperature of 60℃,and leaching solution termination at pH 8.The optimum conditions result in a leaching rate of sodium molybdate of 96.24%.Meanwhile,the content of sodium molybdate reaches 94.08wt%after leaching and removing impurities.Iron and aluminum impurities can be effectively separated by adjusting the pH of the leaching solution with sodium carbonate solution.This research avoids the shortcomings of the traditional process and utilizes the advantages of microwave metallurgy to prepare high-quality sodium molybdate,which provides a new idea for the highvalue utilization of molybdenum concentrate.展开更多
Artificial intelligence,machine learning and deep learning algorithms have been widely used for Maximum Power Point Tracking(MPPT)in solar systems.In the traditional MPPT strategies,following of worldwide Global Maxim...Artificial intelligence,machine learning and deep learning algorithms have been widely used for Maximum Power Point Tracking(MPPT)in solar systems.In the traditional MPPT strategies,following of worldwide Global Maximum Power Point(GMPP)under incomplete concealing conditions stay overwhelming assignment and tracks different nearby greatest power focuses under halfway concealing conditions.The advent of artificial intelligence in MPPT has guaranteed of accurate following of GMPP while expanding the significant performance and efficiency of MPPT under Partial Shading Conditions(PSC).Still the selection of an efficient learning based MPPT is complex because each model has its advantages and drawbacks.Recently,Meta-heuristic algorithm based Learning techniques have provided better tracking efficiency but still exhibit dull performances under PSC.This work represents an excellent optimization based on Spotted Hyena Enabled Reliable BAT(SHERB)learning models,SHERB-MPPT integrated with powerful extreme learning machines to identify the GMPP with fast convergence,low steady-state oscillations,and good tracking efficiency.Extensive testing using MATLAB-SIMULINK,with 50000 data combinations gathered under partial shade and normal settings.As a result of simulations,the proposed approach offers 99.7%tracking efficiency with a slower convergence speed.To demonstrate the predominance of the proposed system,we have compared the performance of the system with other hybrid MPPT learning models.Results proved that the proposed cross breed MPPT model had beaten different techniques in recognizing GMPP viably under fractional concealing conditions.展开更多
Antibiotic resistance is one of the major issues in the medical field and a potential threat to human health.However,newly emerging antimicrobial compounds failed to combat antimicrobial resistance developed by bacter...Antibiotic resistance is one of the major issues in the medical field and a potential threat to human health.However,newly emerging antimicrobial compounds failed to combat antimicrobial resistance developed by bacterial pathogens.Recently,a bismuth-based complex has been developed to eradicate antimicrobial-resistant microorganism infections.The complex is known as organobismuth(III)phosphinate,which is said to be a potential broad-spectrum antimicrobial agent.This complex has been incorporated into the nanocellulose suspension to fabricate a biomedical composite for various applications.The composite can be fabricated by two methods namely vacuum filtration and spray coating.In this paper,the surface and topography of the composite are investigated and discussed in terms of SEM micrographs and their antimicrobial potential.This review focuses on the organo-bismuth nanocellulose composite and its biomedical application in the future.展开更多
Due to their promising applications in foldable displays,optical communication equipment and environmental monitoring systems,flexible and broadband optoelectronic devices have gained extensive attention in recent yea...Due to their promising applications in foldable displays,optical communication equipment and environmental monitoring systems,flexible and broadband optoelectronic devices have gained extensive attention in recent years.Here,a flexible and broadband photodetector based on CsPbBr_(3)/PbSe quantum dot(QD) heterostructures is firstly presented.The integrated QD heterostructures possess consecutive detection range from ultraviolet(UV) to long-wave length infrared(LW-IR) regions with efficient light absorption and chemical stability,in comparison with the pristine PbSe QDs.Systematic material characterizations reveal the improved exciton dissociation,carrier transport and carrier lifetime of the QD heterostructures.Flexible photodetector Ag/CsPbBr_(3)/PbSe/Ag demonstrate a high responsivity of 7.17 A/W with a specific detectivity of 8.97 × 10^(12) Jones under 25 μW/cm^(2) 365 nm illumination at 5 V.Furthermore,it could maintain 91.2 %(or 94.9 %) of its initial performance even after bending for thousands of times(or exposing in ambient air for 4 weeks).More importantly,its re s ponse time is shortened more than three orders of magnitude as that of pristine PbSe QDs-based photodetectors.Therefore,it provides a feasible and promising method for the next-generation high-performance broadband photodetectors via constructing heterostructures of various QDs.展开更多
BACKGROUND Portal hypertension(PH)is associated with changes in vascular structure and function of the portosplenomesenteric system(PSMS).This is referred to as portal hypertensive vasculopathy.Pathological abnormalit...BACKGROUND Portal hypertension(PH)is associated with changes in vascular structure and function of the portosplenomesenteric system(PSMS).This is referred to as portal hypertensive vasculopathy.Pathological abnormalities of PSMS has been described in the literature for cirrhotic patients.Raised portal pressure and hyperdynamic circulation are thought to be the underlying cause of this vasculopathy.In view of this,it is expected that pathological changes in splenic and portal vein similar to those reported in cirrhotic patients with PH may also be present in patients with non-cirrhotic PH(NCPH).AIM To investigate pathological abnormalities of splenic vein in patients with NCPH,and suggest its possible implications in the management of PH.METHODS A prospective observational study was performed on 116 patients with NCPH[Extrahepatic portal vein obstruction(EHPVO):53 and non-cirrhotic portal fibrosis(NCPF):63]who underwent proximal splenorenal shunt(PSRS),interposition shunt or splenectomy with devascularization in JIPMER,Pondicherry,India,a tertiary level referral center,between 2011-2016.All patients were evaluated by Doppler study of PSMS,computed tomography portovenogram and upper gastrointestinal endoscopy.An acoustic resonance forced impulse(ARFI)scan and abdomen ultrasound were done for all cases to exclude cirrhosis.Intraoperative and histopathological assessment of the harvested splenic vein was performed in all.The study group was divided into delayed and early presentation based on the median duration of symptoms(i.e.108 mo).RESULTS The study group comprising of 116 patients[77(66%)females and 39(34%)males]with NCPH had a median age of 22 years.Median duration of symptoms was 108 mo.The most common presentation in both EHPVO and NCPF patients was upper gastrointestinal bleeding(hematemesis and melena).The ARFI scan revealed a median score of 1.2(1.0-1.8)m/s for EHPVO and 1.5(0.9-2.8)m/s for NCPF.PSRS was performed in 84 patients(two of whom underwent interposition PSRS using a 10 mm Dacron graft);splenoadr展开更多
Cerium incorporated KIT-6 mesoporous materials were synthesized through direct hydrothermal method and characterized by using X-ray diffraction (XRD), nitrogen sorption isotherm (BET), Fourier transform infrared s...Cerium incorporated KIT-6 mesoporous materials were synthesized through direct hydrothermal method and characterized by using X-ray diffraction (XRD), nitrogen sorption isotherm (BET), Fourier transform infrared spectroscopy (FT-IR), inductively coupled plasma - atomic emission spectroscopy (ICP-AES), diffuse reflectance ultraviolet visible spectroscopy (DRS-UV-Vis), ther- mogravimetric analysis (TGA), scanning electron microscopy (SEM) and transmission electron microscopy (TEM) methods. It ap- peared that stable cerium ions were inserted into the silica framework of KIT-6, thus generating acid properties in their host materials. The catalytic activity of Ce-KIT-6 materials was evaluated in the vapor phase dehydration of cyclohexanol to cyclohexene and dicy- clohexyl ether at different temperatures with various Si/Ce molar ratios. Ce-KIT-6 (25) showed higher activity with 54% cyclohexa- nol conversion and 64% selectivity to cyclohexene. The catalytic results indicated that Ce-KIT-6 mesoporous materials could be used as versatile and stable acid catalysts.展开更多
Heterojunction is regarded as a crucial step toward realizing high-performance devices,particularly,forming gradient energy band between heterojunctions benefits self-powered photodetectors.Therefore,in this paper,the...Heterojunction is regarded as a crucial step toward realizing high-performance devices,particularly,forming gradient energy band between heterojunctions benefits self-powered photodetectors.Therefore,in this paper,the synthesis of CsPbI3 nanorods(NRs)and its application as the interfacial layer in high-performance,all-solution-processed self-powered photodetectors are presented.For the bilayer photodetector ITO/ZnO(100 nm)/PbS-TBAI(150 nm)/Au,a responsivity of 3.6 A/W with a specific detectivity of 9.8×10^(12)Jones was obtained under 0.1 mW/cm^(2)white light illumination at zero bias(i.e.in self-powered mode).Meanwhile,the photocurrent was enhanced to an On/Off current ratio of 105 at zero bias with an open circuit voltage of 0.53 V for trilayer photodetector ITO/ZnO(100 nm)/PbSTBAI(150 nm)/CsPbI3(250 nm)/Au,in which the CsPbI3 NRs layer works as the interfacial layer.As a result,a specific detectivity of 4.5×10^(13)Jones with a responsivity of 11.12 A/W was obtained under0.1 mW/cm^(2) white light illumination,as well as the rising/decaying time of 0.57 s/0.41 s with excellent stability and reproducibility upto four weeks in air.The enhanced-performance is ascribed to the mismatch bandgap between PbS-TBAI/CsPbI_(3)interface,which can suppress the carrier recombination and provide efficient transport passages for charge carriers.Thus,it provides a feasible and efficient method for high-performance photodetectors.展开更多
Plants and plant-based products are the bases of many modern pharmaceuticals that are current in use today for various diseases.The aim of the study was to investigate the biochemical constituents and high performance...Plants and plant-based products are the bases of many modern pharmaceuticals that are current in use today for various diseases.The aim of the study was to investigate the biochemical constituents and high performance thin layer chromatography(HPTLC) finger printing of the ethanolic extract of Evolvulus alsinoides.Phytochemical screening was done by standard procedures and HPTLC method was also established to analyze alkaloids,flavonoids and phenolic compounds from the ethanolic extract of Evolvulus alsinoides.Preliminary phytochemical screening showed that ethanol extracted more secondary metabolites than other solvents.HPTLC fingerprinting analysis showed the presence of various alkaloids,flavonoids and phenols(quercetin) in the ethanolic extract.It can be concluded that Evolvulus alsinoides may serve as a source of potent antioxidants that may be used in the prevention of various diseases such as cancer,diabetes and cardiovascular diseases due to the presence of phenolic compounds.HPTLC finger print of Evolvulus alsinoides may be useful in the differentiation of the species from adulterants and act as a biochemical marker for this medicinally important plant in the pharmaceutical industry and plant systematic studies.展开更多
Given the demographic trends toward a considerably longer life expectancy,the percentage of elderly patients with prostate cancer will increase further in the upcoming decades.Therefore,the question arises,should pati...Given the demographic trends toward a considerably longer life expectancy,the percentage of elderly patients with prostate cancer will increase further in the upcoming decades.Therefore,the question arises,should patients ≥75 years old be offered radical prostatectomy and under which circumstances? For treatment decision-making,life expectancy is more important than biological age.As a result,a patient's health and mental status has to be determined and radical treatment should only be offered to those who are fit.As perioperative morbidity and mortality in these patients is increased relative to younger patients,patient selection according to comorbidities is a key issue that needs to be addressed.It is known from the literature that elderly men show notably worse tumor characteristics,leading to worse oncologic outcomes after treatment.Moreover,elderly patients also demonstrate worse postoperative recovery of continence and erectile function.As the absolute rates of both oncological and functional outcomes are still very reasonable in patients ≥75 years,a radical prostatectomy can be offered to highly selected and healthy elderly patients. Nevertheless,patients clearly need to be informed about the worse outcomes and higher perioperative risks compared to younger patients.展开更多
We provide an approximate method to determine the dominant heat transport mechanism responsible for the anomalous enhancement of thermal conductivity in aqueous nanofluids. Due to a large degree of randomness and scat...We provide an approximate method to determine the dominant heat transport mechanism responsible for the anomalous enhancement of thermal conductivity in aqueous nanofluids. Due to a large degree of randomness and scatter observed in the published experimental data, limits to nanofluid thermal conductivity are fixed analytically by taking into account the contribution of particle Brownian motion and clustering, and a regime diagram is developed. Experimental data from a range of independent published sources is used for validation of the developed regime diagram.展开更多
Barrett’s esophagus(BE)is a well-established risk factor for esophageal adenocarcinoma.It is recommended that patients have regular endoscopic surveillance,with the ultimate goal of detecting early-stage neoplastic l...Barrett’s esophagus(BE)is a well-established risk factor for esophageal adenocarcinoma.It is recommended that patients have regular endoscopic surveillance,with the ultimate goal of detecting early-stage neoplastic lesions before they can progress to invasive carcinoma.Detection of both dysplasia or early adenocarcinoma permits curative endoscopic treatments,and with this aim,thorough endoscopic assessment is crucial and improves outcomes.The burden of missed neoplasia in BE is still far from being negligible,likely due to inappropriate endoscopic surveillance.Over the last two decades,advanced imaging techniques,moving from traditional dye-spray chromoendoscopy to more practical virtual chromoendoscopy technologies,have been introduced with the aim to enhance neoplasia detection in BE.As witnessed in other fields,artificial intelligence(AI)has revolutionized the field of diagnostic endoscopy and is set to cover a pivotal role in BE as well.The aim of this commentary is to comprehensively summarize present evidence,recent research advances,and future perspectives regarding advanced imaging technology and AI in BE;the combination of computer-aided diagnosis to a widespread adoption of advanced imaging technologies is eagerly awaited.It will also provide a useful step-by-step approach for performing high-quality endoscopy in BE,in order to increase the diagnostic yield of endoscopy in clinical practice.展开更多
Investigation of a beach and its wave condi-tions is highly requisite for understanding the physicalprocesses in a coast. This study composes spatial andtemporal correlation between beach and nearshore pro-cesses alon...Investigation of a beach and its wave condi-tions is highly requisite for understanding the physicalprocesses in a coast. This study composes spatial andtemporal correlation between beach and nearshore pro-cesses along the extensive sandy beach of Nagapattinamcoast, southeast peninsular India. The data collectionincludes beach profile, wave data, and intertidal sedimentsamples for 2 years from January 2011 to January 2013.The field data revealed significant variability in beach andwave morphology during the northeast (NE) and southwest(SW) monsoon. However, the beach has been stabilized bythe reworking of sediment distribution during the calmperiod. The changes in grain sorting and longshoresediment transport serve as a clear evidence of thesediment migration that persevered between foreshoreand nearshore regions. The Empirical Orthogonal Function(EOF) analysis and Canonical Correlation Analysis (CCA)were utilized to investigate the spatial and temporallinkages between beach and nearshore criterions. Theoutcome of the multivariate analysis unveiled that theseasonal variations in the wave climate tends to influencethe bar - berm sediment transition that is discerned in thecoast.展开更多
Several studies have shown a significant adenoma miss rate up to 35%during screening colonoscopy,especially in patients with diminutive adenomas.The use of artificial intelligence(AI)in colonoscopy has been gaining po...Several studies have shown a significant adenoma miss rate up to 35%during screening colonoscopy,especially in patients with diminutive adenomas.The use of artificial intelligence(AI)in colonoscopy has been gaining popularity by helping endoscopists in polyp detection,with the aim to increase their adenoma detection rate(ADR)and polyp detection rate(PDR)in order to reduce the incidence of interval cancers.The efficacy of deep convolutional neural network(DCNN)-based AI system for polyp detection has been trained and tested in ex vivo settings such as colonoscopy still images or videos.Recent trials have evaluated the real-time efficacy of DCNN-based systems showing promising results in term of improved ADR and PDR.In this review we reported data from the preliminary ex vivo experiences and summarized the results of the initial randomized controlled trials.展开更多
Measurement-induced nonlocality(MIN),a quantum correlation measure for bipartite systems,is an indicator of maximal global effects due to locally invariant von Neumann projective measurements.It is originally defined ...Measurement-induced nonlocality(MIN),a quantum correlation measure for bipartite systems,is an indicator of maximal global effects due to locally invariant von Neumann projective measurements.It is originally defined as the maximal square of the Hilbert-Schmidt norm of the difference between pre-and post-measurement states.In this article,we propose a new form of MIN based on affinity.This quantity satisfies all the criteria of a bona fide measure of quantum correlation measures.This quantity is evaluated for both arbitrary pure and 2×n dimensional(qubit-qudit)mixed states.The operational meaning of the proposed quantity is interpreted in terms of the interferometric power of the quantum state.We apply these results on two-qubit mixed states,such as the Werner,isotropic and Bell diagonal states.展开更多
The experimental investigations on the effect of the fly ash particle size, velocity, impingement angle, and feed rate were done with an emphasis on the effect of erosion on annealed SA 210 GrA1 (A) and normalized S...The experimental investigations on the effect of the fly ash particle size, velocity, impingement angle, and feed rate were done with an emphasis on the effect of erosion on annealed SA 210 GrA1 (A) and normalized SA 210 GrA1 (N) carbon steel economizer-tube materials. Erosion rates were evaluated with different impingement angles ranging from 15° to 90°, at four different velocities of 32.5, 35, 37.5, and 40 m/s, and at four different feed rates of fly ash particles of 2, 4, 6 and 8 g/min. The erodent used was fly ash particles, sizes ranging from 50-250 μm of irregular shapes. Erosion rate is found to be the maximum at the impingement angle of 30°. Erosion rates of the carbon steel tube in different heat treatment conditions, annealed and normalized, at a constant velocity of 32.5 m/s with different angles were studied. In all cases of feed rates, impingement angles, particle sizes, and velocities of fly ash particles, it has been found that the erosion rate of the annealed tube is less than that of the normalized tube. Empirical correlations for erosion rate relating the velocity, size, feed rate, and impingement angle of the particles and elongation property of the target materials were arrived. Morphologies of the eroded surface were examined by scanning electron microscope (SEM).展开更多
基金Supported by the Natural Resources Data Management System,Department of Science and Technology,Government of India Under Project Scheme (No.ES/11/546/2000,No.ES/11/936(5)/05)
文摘The shoreline is one of the rapidly changing landforms in coastal areas. They are the key element in coastal GIS and provide the most information on coastal land form dynamics. Therefore, accurate detection and frequent monitoring of shorelines is very essential to understand the coastal processes and dynamics of various coastal features. The present study is to investigate the shoreline changes along the coast between Kanyakumari and Tuticorin of south India (where hydrodynamic and morphologic changes occur continuously after the December 2004 tsunami) by using Digital Shoreline Analysis System (DSAS), an extension of ArcGIS. Multidate 1RS and Landsat Satellite data (1999, 2001, 2003, 2005, 2007, and 2009) are used to extract the shorelines. The data is processed by using the ERDAS IMAGINE 9.1 software and analyzed by ArcGIS 9.2 workstation. The rates of shoreline changes are estimated by three statistical methods, namely, End Point Rate (EPR), Linear Regression Rate (LRR), and Least Median of Squares (LMS) by using DSAS. The study reveals that most of the study area has undergoing erosion. Both natural and anthropogenic processes along the coast modify the shoreline configuration and control the erosion and accretion of the coastal zones. The coastal zones along the estuary have experienced accretion due to the littoral processes. The zones with headlands have more eroded than other zones along the study area. The study also shows that the coastal zones where sand is mined have relatively more rate of erosion than that of the other zones. Improper and unsustainable sand mining may also lead to severe erosion problem along this area. The shoreline change rates are altered by various geological processes along the coast. Thus, the present study implies that proper beach filling and nourishment projects should be made in the study area to save from hazards. It also indicates the advantage and suitability of DSAS to assess the shoreline changes compared with the traditional manual shoreline
基金supported by the National Natural Science Foundation of China(Grant Nos.61573096 and 61272530)the Natural Science Foundation of Jiangsu Province of China(Grant No.BK2012741)the 333 Engineering Foundation of Jiangsu Province of China(Grant No.BRA2015286)
文摘This paper is concerned with the exponential H_∞ filtering problem for a class of discrete-time switched neural networks with random time-varying delays based on the sojourn-probability-dependent method. Using the average dwell time approach together with the piecewise Lyapunov function technique, sufficient conditions are proposed to guarantee the exponential stability for the switched neural networks with random time-varying delays which are characterized by introducing a Bernoulli stochastic variable.Based on the derived H_∞ performance analysis results, the H_∞ filter design is formulated in terms of Linear Matrix Inequalities(LMIs). Finally, two numerical examples are presented to demonstrate the effectiveness of the proposed design procedure.
文摘Applying indocyanine green(ICG)fluorescence in surgery has created a new dimension of navigation surgery to advance in various disciplines.The research in this field is nascent and fragmented,necessitating academic efforts to gain a comprehensive understanding.The present review aims to integrate diverse perspectives and recent advances in its application in gastrointestinal surgery.The relevant articles were selected by using the appropriate keyword search in PubMed.The angiography and cholangiography property of ICG fluorescence is helpful in various hepatobiliary disorders.In gastroesophageal and colorectal surgery,the lymphangiography and angiography property of ICG is applied to evaluate bowel vascularity and guide lymphadenectomy.The lack of objective parameters to assess ICG fluorescence has been the primary limitation when ICG is used to evaluate bowel perfusion.The optimum dose and timing of ICG administration need to be standardized in some new application areas in gastrointestinal surgery.Binding tumor-specific ligands with fluorophores can potentially widen the fluorescence application to detect primary and metastatic gastrointestinal tumors.The narrative review outlines prior contributions,limitations,and research opportunities for future studies across gastrointestinal sub-specialty.The findings of the present review would be helpful for scholars and practitioners to explore and progress in this exciting domain of gastrointestinal surgery.
基金financially supported by the National Natural Science Foundation of China (No.51964046)。
文摘The preparation process of sodium molybdate has the disadvantages of high energy consumption,low thermal efficiency,and high raw material requirement of molybdenum trioxide,in order to realize the green and efficient development of molybdenum concentrate resources,this paper proposes a new process for efficient recovery of molybdenum from molybdenum concentrate and preparation of sodium molybdate by microwave-enhanced roasting and alkali leaching.Thermodynamic analysis indicated the feasibility of oxidation roasting of molybdenum concentrate.The effects of roasting temperature,holding time,and power-to-mass ratio on the oxidation product and leaching product sodium molybdate (Na_(2)MoO_(4)·2H_(2)O) were investigated.Under the optimal process conditions:roasting temperature of 700℃,holding time of 110 min,and power-to-mass ratio of 110 W/g,the molybdenum state of existence was converted from MoS_(2) to Mo O3.The process of preparing sodium molybdate by alkali leaching of molybdenum calcine was investigated,the optimal leaching conditions include a solution concentration of 2.5 mol/L,a liquid-to-solid ratio of 2 mL/g,a leaching temperature of 60℃,and leaching solution termination at pH 8.The optimum conditions result in a leaching rate of sodium molybdate of 96.24%.Meanwhile,the content of sodium molybdate reaches 94.08wt%after leaching and removing impurities.Iron and aluminum impurities can be effectively separated by adjusting the pH of the leaching solution with sodium carbonate solution.This research avoids the shortcomings of the traditional process and utilizes the advantages of microwave metallurgy to prepare high-quality sodium molybdate,which provides a new idea for the highvalue utilization of molybdenum concentrate.
文摘Artificial intelligence,machine learning and deep learning algorithms have been widely used for Maximum Power Point Tracking(MPPT)in solar systems.In the traditional MPPT strategies,following of worldwide Global Maximum Power Point(GMPP)under incomplete concealing conditions stay overwhelming assignment and tracks different nearby greatest power focuses under halfway concealing conditions.The advent of artificial intelligence in MPPT has guaranteed of accurate following of GMPP while expanding the significant performance and efficiency of MPPT under Partial Shading Conditions(PSC).Still the selection of an efficient learning based MPPT is complex because each model has its advantages and drawbacks.Recently,Meta-heuristic algorithm based Learning techniques have provided better tracking efficiency but still exhibit dull performances under PSC.This work represents an excellent optimization based on Spotted Hyena Enabled Reliable BAT(SHERB)learning models,SHERB-MPPT integrated with powerful extreme learning machines to identify the GMPP with fast convergence,low steady-state oscillations,and good tracking efficiency.Extensive testing using MATLAB-SIMULINK,with 50000 data combinations gathered under partial shade and normal settings.As a result of simulations,the proposed approach offers 99.7%tracking efficiency with a slower convergence speed.To demonstrate the predominance of the proposed system,we have compared the performance of the system with other hybrid MPPT learning models.Results proved that the proposed cross breed MPPT model had beaten different techniques in recognizing GMPP viably under fractional concealing conditions.
文摘Antibiotic resistance is one of the major issues in the medical field and a potential threat to human health.However,newly emerging antimicrobial compounds failed to combat antimicrobial resistance developed by bacterial pathogens.Recently,a bismuth-based complex has been developed to eradicate antimicrobial-resistant microorganism infections.The complex is known as organobismuth(III)phosphinate,which is said to be a potential broad-spectrum antimicrobial agent.This complex has been incorporated into the nanocellulose suspension to fabricate a biomedical composite for various applications.The composite can be fabricated by two methods namely vacuum filtration and spray coating.In this paper,the surface and topography of the composite are investigated and discussed in terms of SEM micrographs and their antimicrobial potential.This review focuses on the organo-bismuth nanocellulose composite and its biomedical application in the future.
基金partially funded by the Project of State Key Laboratory of Transducer Technology (No. SKT1404)the Fundamental Research Funds for the Central Universities (No. 2020CX02002 and BITBLR2020013)the Key R&D Projects of the Ministry of Science and Technology (No. SQ2019YFB220038)。
文摘Due to their promising applications in foldable displays,optical communication equipment and environmental monitoring systems,flexible and broadband optoelectronic devices have gained extensive attention in recent years.Here,a flexible and broadband photodetector based on CsPbBr_(3)/PbSe quantum dot(QD) heterostructures is firstly presented.The integrated QD heterostructures possess consecutive detection range from ultraviolet(UV) to long-wave length infrared(LW-IR) regions with efficient light absorption and chemical stability,in comparison with the pristine PbSe QDs.Systematic material characterizations reveal the improved exciton dissociation,carrier transport and carrier lifetime of the QD heterostructures.Flexible photodetector Ag/CsPbBr_(3)/PbSe/Ag demonstrate a high responsivity of 7.17 A/W with a specific detectivity of 8.97 × 10^(12) Jones under 25 μW/cm^(2) 365 nm illumination at 5 V.Furthermore,it could maintain 91.2 %(or 94.9 %) of its initial performance even after bending for thousands of times(or exposing in ambient air for 4 weeks).More importantly,its re s ponse time is shortened more than three orders of magnitude as that of pristine PbSe QDs-based photodetectors.Therefore,it provides a feasible and promising method for the next-generation high-performance broadband photodetectors via constructing heterostructures of various QDs.
文摘BACKGROUND Portal hypertension(PH)is associated with changes in vascular structure and function of the portosplenomesenteric system(PSMS).This is referred to as portal hypertensive vasculopathy.Pathological abnormalities of PSMS has been described in the literature for cirrhotic patients.Raised portal pressure and hyperdynamic circulation are thought to be the underlying cause of this vasculopathy.In view of this,it is expected that pathological changes in splenic and portal vein similar to those reported in cirrhotic patients with PH may also be present in patients with non-cirrhotic PH(NCPH).AIM To investigate pathological abnormalities of splenic vein in patients with NCPH,and suggest its possible implications in the management of PH.METHODS A prospective observational study was performed on 116 patients with NCPH[Extrahepatic portal vein obstruction(EHPVO):53 and non-cirrhotic portal fibrosis(NCPF):63]who underwent proximal splenorenal shunt(PSRS),interposition shunt or splenectomy with devascularization in JIPMER,Pondicherry,India,a tertiary level referral center,between 2011-2016.All patients were evaluated by Doppler study of PSMS,computed tomography portovenogram and upper gastrointestinal endoscopy.An acoustic resonance forced impulse(ARFI)scan and abdomen ultrasound were done for all cases to exclude cirrhosis.Intraoperative and histopathological assessment of the harvested splenic vein was performed in all.The study group was divided into delayed and early presentation based on the median duration of symptoms(i.e.108 mo).RESULTS The study group comprising of 116 patients[77(66%)females and 39(34%)males]with NCPH had a median age of 22 years.Median duration of symptoms was 108 mo.The most common presentation in both EHPVO and NCPF patients was upper gastrointestinal bleeding(hematemesis and melena).The ARFI scan revealed a median score of 1.2(1.0-1.8)m/s for EHPVO and 1.5(0.9-2.8)m/s for NCPF.PSRS was performed in 84 patients(two of whom underwent interposition PSRS using a 10 mm Dacron graft);splenoadr
文摘Cerium incorporated KIT-6 mesoporous materials were synthesized through direct hydrothermal method and characterized by using X-ray diffraction (XRD), nitrogen sorption isotherm (BET), Fourier transform infrared spectroscopy (FT-IR), inductively coupled plasma - atomic emission spectroscopy (ICP-AES), diffuse reflectance ultraviolet visible spectroscopy (DRS-UV-Vis), ther- mogravimetric analysis (TGA), scanning electron microscopy (SEM) and transmission electron microscopy (TEM) methods. It ap- peared that stable cerium ions were inserted into the silica framework of KIT-6, thus generating acid properties in their host materials. The catalytic activity of Ce-KIT-6 materials was evaluated in the vapor phase dehydration of cyclohexanol to cyclohexene and dicy- clohexyl ether at different temperatures with various Si/Ce molar ratios. Ce-KIT-6 (25) showed higher activity with 54% cyclohexa- nol conversion and 64% selectivity to cyclohexene. The catalytic results indicated that Ce-KIT-6 mesoporous materials could be used as versatile and stable acid catalysts.
基金partially funded by the project of State Key Laboratory of Transducer Technology(SKT1404)the project of the Key Laboratory of Photoelectronic Imaging Technology and System(2017OEIOF02)Beijing Institute of Technology,Ministry of Education of Chinathe project of the Key R&D projects of the Ministry of Science and Technology(SQ2019YFB220038)。
文摘Heterojunction is regarded as a crucial step toward realizing high-performance devices,particularly,forming gradient energy band between heterojunctions benefits self-powered photodetectors.Therefore,in this paper,the synthesis of CsPbI3 nanorods(NRs)and its application as the interfacial layer in high-performance,all-solution-processed self-powered photodetectors are presented.For the bilayer photodetector ITO/ZnO(100 nm)/PbS-TBAI(150 nm)/Au,a responsivity of 3.6 A/W with a specific detectivity of 9.8×10^(12)Jones was obtained under 0.1 mW/cm^(2)white light illumination at zero bias(i.e.in self-powered mode).Meanwhile,the photocurrent was enhanced to an On/Off current ratio of 105 at zero bias with an open circuit voltage of 0.53 V for trilayer photodetector ITO/ZnO(100 nm)/PbSTBAI(150 nm)/CsPbI3(250 nm)/Au,in which the CsPbI3 NRs layer works as the interfacial layer.As a result,a specific detectivity of 4.5×10^(13)Jones with a responsivity of 11.12 A/W was obtained under0.1 mW/cm^(2) white light illumination,as well as the rising/decaying time of 0.57 s/0.41 s with excellent stability and reproducibility upto four weeks in air.The enhanced-performance is ascribed to the mismatch bandgap between PbS-TBAI/CsPbI_(3)interface,which can suppress the carrier recombination and provide efficient transport passages for charge carriers.Thus,it provides a feasible and efficient method for high-performance photodetectors.
文摘Plants and plant-based products are the bases of many modern pharmaceuticals that are current in use today for various diseases.The aim of the study was to investigate the biochemical constituents and high performance thin layer chromatography(HPTLC) finger printing of the ethanolic extract of Evolvulus alsinoides.Phytochemical screening was done by standard procedures and HPTLC method was also established to analyze alkaloids,flavonoids and phenolic compounds from the ethanolic extract of Evolvulus alsinoides.Preliminary phytochemical screening showed that ethanol extracted more secondary metabolites than other solvents.HPTLC fingerprinting analysis showed the presence of various alkaloids,flavonoids and phenols(quercetin) in the ethanolic extract.It can be concluded that Evolvulus alsinoides may serve as a source of potent antioxidants that may be used in the prevention of various diseases such as cancer,diabetes and cardiovascular diseases due to the presence of phenolic compounds.HPTLC finger print of Evolvulus alsinoides may be useful in the differentiation of the species from adulterants and act as a biochemical marker for this medicinally important plant in the pharmaceutical industry and plant systematic studies.
文摘Given the demographic trends toward a considerably longer life expectancy,the percentage of elderly patients with prostate cancer will increase further in the upcoming decades.Therefore,the question arises,should patients ≥75 years old be offered radical prostatectomy and under which circumstances? For treatment decision-making,life expectancy is more important than biological age.As a result,a patient's health and mental status has to be determined and radical treatment should only be offered to those who are fit.As perioperative morbidity and mortality in these patients is increased relative to younger patients,patient selection according to comorbidities is a key issue that needs to be addressed.It is known from the literature that elderly men show notably worse tumor characteristics,leading to worse oncologic outcomes after treatment.Moreover,elderly patients also demonstrate worse postoperative recovery of continence and erectile function.As the absolute rates of both oncological and functional outcomes are still very reasonable in patients ≥75 years,a radical prostatectomy can be offered to highly selected and healthy elderly patients. Nevertheless,patients clearly need to be informed about the worse outcomes and higher perioperative risks compared to younger patients.
文摘We provide an approximate method to determine the dominant heat transport mechanism responsible for the anomalous enhancement of thermal conductivity in aqueous nanofluids. Due to a large degree of randomness and scatter observed in the published experimental data, limits to nanofluid thermal conductivity are fixed analytically by taking into account the contribution of particle Brownian motion and clustering, and a regime diagram is developed. Experimental data from a range of independent published sources is used for validation of the developed regime diagram.
文摘Barrett’s esophagus(BE)is a well-established risk factor for esophageal adenocarcinoma.It is recommended that patients have regular endoscopic surveillance,with the ultimate goal of detecting early-stage neoplastic lesions before they can progress to invasive carcinoma.Detection of both dysplasia or early adenocarcinoma permits curative endoscopic treatments,and with this aim,thorough endoscopic assessment is crucial and improves outcomes.The burden of missed neoplasia in BE is still far from being negligible,likely due to inappropriate endoscopic surveillance.Over the last two decades,advanced imaging techniques,moving from traditional dye-spray chromoendoscopy to more practical virtual chromoendoscopy technologies,have been introduced with the aim to enhance neoplasia detection in BE.As witnessed in other fields,artificial intelligence(AI)has revolutionized the field of diagnostic endoscopy and is set to cover a pivotal role in BE as well.The aim of this commentary is to comprehensively summarize present evidence,recent research advances,and future perspectives regarding advanced imaging technology and AI in BE;the combination of computer-aided diagnosis to a widespread adoption of advanced imaging technologies is eagerly awaited.It will also provide a useful step-by-step approach for performing high-quality endoscopy in BE,in order to increase the diagnostic yield of endoscopy in clinical practice.
文摘Investigation of a beach and its wave condi-tions is highly requisite for understanding the physicalprocesses in a coast. This study composes spatial andtemporal correlation between beach and nearshore pro-cesses along the extensive sandy beach of Nagapattinamcoast, southeast peninsular India. The data collectionincludes beach profile, wave data, and intertidal sedimentsamples for 2 years from January 2011 to January 2013.The field data revealed significant variability in beach andwave morphology during the northeast (NE) and southwest(SW) monsoon. However, the beach has been stabilized bythe reworking of sediment distribution during the calmperiod. The changes in grain sorting and longshoresediment transport serve as a clear evidence of thesediment migration that persevered between foreshoreand nearshore regions. The Empirical Orthogonal Function(EOF) analysis and Canonical Correlation Analysis (CCA)were utilized to investigate the spatial and temporallinkages between beach and nearshore criterions. Theoutcome of the multivariate analysis unveiled that theseasonal variations in the wave climate tends to influencethe bar - berm sediment transition that is discerned in thecoast.
文摘Several studies have shown a significant adenoma miss rate up to 35%during screening colonoscopy,especially in patients with diminutive adenomas.The use of artificial intelligence(AI)in colonoscopy has been gaining popularity by helping endoscopists in polyp detection,with the aim to increase their adenoma detection rate(ADR)and polyp detection rate(PDR)in order to reduce the incidence of interval cancers.The efficacy of deep convolutional neural network(DCNN)-based AI system for polyp detection has been trained and tested in ex vivo settings such as colonoscopy still images or videos.Recent trials have evaluated the real-time efficacy of DCNN-based systems showing promising results in term of improved ADR and PDR.In this review we reported data from the preliminary ex vivo experiences and summarized the results of the initial randomized controlled trials.
文摘Measurement-induced nonlocality(MIN),a quantum correlation measure for bipartite systems,is an indicator of maximal global effects due to locally invariant von Neumann projective measurements.It is originally defined as the maximal square of the Hilbert-Schmidt norm of the difference between pre-and post-measurement states.In this article,we propose a new form of MIN based on affinity.This quantity satisfies all the criteria of a bona fide measure of quantum correlation measures.This quantity is evaluated for both arbitrary pure and 2×n dimensional(qubit-qudit)mixed states.The operational meaning of the proposed quantity is interpreted in terms of the interferometric power of the quantum state.We apply these results on two-qubit mixed states,such as the Werner,isotropic and Bell diagonal states.
文摘The experimental investigations on the effect of the fly ash particle size, velocity, impingement angle, and feed rate were done with an emphasis on the effect of erosion on annealed SA 210 GrA1 (A) and normalized SA 210 GrA1 (N) carbon steel economizer-tube materials. Erosion rates were evaluated with different impingement angles ranging from 15° to 90°, at four different velocities of 32.5, 35, 37.5, and 40 m/s, and at four different feed rates of fly ash particles of 2, 4, 6 and 8 g/min. The erodent used was fly ash particles, sizes ranging from 50-250 μm of irregular shapes. Erosion rate is found to be the maximum at the impingement angle of 30°. Erosion rates of the carbon steel tube in different heat treatment conditions, annealed and normalized, at a constant velocity of 32.5 m/s with different angles were studied. In all cases of feed rates, impingement angles, particle sizes, and velocities of fly ash particles, it has been found that the erosion rate of the annealed tube is less than that of the normalized tube. Empirical correlations for erosion rate relating the velocity, size, feed rate, and impingement angle of the particles and elongation property of the target materials were arrived. Morphologies of the eroded surface were examined by scanning electron microscope (SEM).