AIM: To compare the liver stiffness (LS) measurement by transient elastography (TE) to the liver biopsy (LB)-considered the "gold standard" in the evaluation of patients with chronic hepatitis C. METHODS: Du...AIM: To compare the liver stiffness (LS) measurement by transient elastography (TE) to the liver biopsy (LB)-considered the "gold standard" in the evaluation of patients with chronic hepatitis C. METHODS: During a period of 12 mo, we evaluated 199 consecutive patients with chronic hepatitis due to hepatitis C virus (HCV), in which LB and LS assessments (by means of TE) were performed during the same session. RESULTS: Out of 199 patients, a valid measurement of the LS could not be obtained in 8. The mean value of LS in the cohort of 191 valid measurements was 8.45 ± 4.96 kPa, ranging from 2.3 to 38 kPa. The mean value of LS in patients with signifi cant fi brosis at biopsy (161 patients with F ≥ 2 according to Metavir) was 9.02 ± 5.15 kPa, significantly higher than in patients with no or mild fi brosis (30 patients with F < 2 Metavir): 5.39 ± 1.81 kPa (P < 0.0001). For a cut- off value of 6.8 kPa, the LS had a PPV of 98%, a NPV of 30.1%, a sensitivity of 59.6% and a specificity of 93.3% for the presence of signifi cant fi brosis (at least F2 Metavir), with a diagnostic performance of 77.3% (AUROC 0.773). Using this cut-off value, we reached the best discrimination between absence of fibrosis/ mild fibrosis (F < 2 Metavir) and the presence ofmoderate to severe fi brosis (F ≥ 2 Metavir). CONCLUSION: In patients with chronic hepatitis due to HCV, a cut-off value of 6.8 kPa measured by TE can differentiate between significant fibrosis and absent or mild fi brosis, with a PPV of 98%, a NPV of 30.1%, a sensitivity of 59.6%, a specificity of 93.3%, and a diagnostic performance of 77.3%.展开更多
AIM:To determine whether acoustic radiation force impulse(ARFI) elastography is a reliable method for predicting fibrosis severity in patients with chronic hepatitis C virus(HCV) hepatitis.METHODS:We performed a multi...AIM:To determine whether acoustic radiation force impulse(ARFI) elastography is a reliable method for predicting fibrosis severity in patients with chronic hepatitis C virus(HCV) hepatitis.METHODS:We performed a multicenter study including 274 subjects with HCV chronic hepatitis in which we compared ARFI with liver biopsy(LB).In each patient we performed LB(evaluated according to the Metavir score) and ARFI measurements(using a Siemens Acuson S2000TM ultrasound system:10 valid measurements were performed and median values were calculated and expressed in meters/second(m/s).RESULTS:A direct,strong,correlation(Spearman r = 0.707) was found between ARFI measurements and fibrosis(P < 0.0001).For predicting the presence of fibrosis(F ≥ 1 Metavir),significant fibrosis(F ≥ 2),severe fibrosis(F ≥ 3) and cirrhosis(F = 4),the cutoff values of 1.19,1.21,1.58 and 1.82 m/s were determined,respectively,liver stiffness measurements had 73%,84%,84% and 91% Se respectively;93%,91%,94%,90% Sp,respectively;with AUROCs of 0.880,0.893,0.908 and 0.937,respectively.CONCLUSION:ARFI measurement is a reliable method for predicting the severity of fibrosis in HCV展开更多
Pancreatic cancer(PC)has a low incidence rate but a high mortality,with patients often in the advanced stage of the disease at the time of the first diagnosis.If detected,early neoplastic lesions are ideal for surgery...Pancreatic cancer(PC)has a low incidence rate but a high mortality,with patients often in the advanced stage of the disease at the time of the first diagnosis.If detected,early neoplastic lesions are ideal for surgery,offering the best prognosis.Preneoplastic lesions of the pancreas include pancreatic intraepithelial neoplasia and mucinous cystic neoplasms,with intraductal papillary mucinous neoplasms being the most commonly diagnosed.Our study focused on predicting PC by identifying early signs using noninvasive techniques and artificial intelligence(AI).A systematic English literature search was conducted on the PubMed electronic database and other sources.We obtained a total of 97 studies on the subject of pancreatic neoplasms.The final number of articles included in our study was 44,34 of which focused on the use of AI algorithms in the early diagnosis and prediction of pancreatic lesions.AI algorithms can facilitate diagnosis by analyzing massive amounts of data in a short period of time.Correlations can be made through AI algorithms by expanding image and electronic medical records databases,which can later be used as part of a screening program for the general population.AI-based screening models should involve a combination of biomarkers and medical and imaging data from different sources.This requires large numbers of resources,collaboration between medical practitioners,and investment in medical infrastructures.展开更多
Domestic cats represent one of the most common sources of indoor allergens.All over the world,many households own cats,whose allergens are persistent and widespread.Cat allergy itself is frequent,and its symptoms vary...Domestic cats represent one of the most common sources of indoor allergens.All over the world,many households own cats,whose allergens are persistent and widespread.Cat allergy itself is frequent,and its symptoms vary from rhinoconjunctivitis to life-threatening asthma.In vitro diagnosis using precision medicine allergy immunoassays is important because natural cat dander extracts may differ in quality and quantity of some of the individual allergen components and other molecules.In the component-resolved diagnosis of cat allergy,singleplex and multiplex specific immunoglobulin(Ig)E assays include use of the cat-specific major allergen,secretoglobin Fel d 1(as a species-specific molecule),other allergen components(such as lipocalins Fel d 4,cross-reacting with other animal similar molecules,and Fel d 7,present in small quantities in natural extracts),and serum albumin Fel d 2(related to the cat-pork syndrome).IgA Fel d 5 and IgM Fel d 6 are not available as allergen components in the current commercial IgE immunoassays,but they may impair the in vitro diagnostic evaluation of cat allergy because galactose-α1,3-galactose is an IgE-binding epitope of these native feline allergens.The benefits of molecular-based cat allergy diagnosis are continually evaluated,as the role of recombinant allergen components already known is detailed and new other molecules of interest may be discovered in the future.展开更多
Black locust(Robinia pseudoacacia L.) was the first North-American tree species imported to Europe at the beginning of the seventeenth century. It is commonly planted worldwide because of its adaptability to environme...Black locust(Robinia pseudoacacia L.) was the first North-American tree species imported to Europe at the beginning of the seventeenth century. It is commonly planted worldwide because of its adaptability to environmental stresses, its valuable wood, easy propagation, frequent and abundant seed production, excellent coppicing,high seedling survival, and relatively high wood yield. In Europe, Romania and Hungary have the most highly-developed black locust growing techniques and experiences.As a result of increasing interest in black locust in many countries, this review aims to provide a comprehensive overview of state-of-the-art site requirements, propagation, improvement and management(including growth and yield as well as use in energy plantations).展开更多
Starting with Faraday’s law of electromagnetic induction in 1831,electric(electromagnetic)machines have been developed ever since as“assembles”of electric and magnetic coupled circuits that convert mechanical to el...Starting with Faraday’s law of electromagnetic induction in 1831,electric(electromagnetic)machines have been developed ever since as“assembles”of electric and magnetic coupled circuits that convert mechanical to electrical energy(in generators)and vice versa(in motors),via magnetic energy storage.Generators and motors are reversible.The Maxwell four equations(laws)later in 19th Century have prompted the rapid development of all basic(DC.brush and travelling field AC machines by 1900.Then by 1930 AC(alternating current)power(energy)systems evolved by connecting in parallel electric synchronous generators(with voltage boost and buck electric transformers for efficient AC power transmission lines)of rather constant frequency and voltage,driven by turbines(prime movers)that harness fossil(coal,gas or nuclear fuels),thermal or hydro energy.The last 50 years have witnessed a dramatic extension of generators power/unit,renewable energy generators and of variable speed AC motor drives in applications with variable output such as ventilators,pumps compressors,conveyors,orr-mills,electric transport(mobility),industrial automation,robotics,home appliances and info-gadgets.This formidable development,required by the need of more but cleaner energy,was mainly driven by power electronics,better materials,better modeling,design methodologies and digital control.This humble inaugural overview attempts to combine a brief history of electrical generators and motors with recent progress and trends in their design and control,for representative applications.展开更多
This paper discusses the early silviculture of silver fir(Abies alba Mill.), a major softwood in Romania covering more than 294,000 ha. Three research plots(DRP1, DRP2 and DRP3) were established in a 25-year-old silve...This paper discusses the early silviculture of silver fir(Abies alba Mill.), a major softwood in Romania covering more than 294,000 ha. Three research plots(DRP1, DRP2 and DRP3) were established in a 25-year-old silver fir-dominated stand in May 2012. In DRP1 and DRP2, heavy cleaning-respacing were carried out while DRP3 was kept as a control. After the treatments in 2012,the plots had stocking between 1470 trees ha-1(DRP2) and10,030 trees ha-1(DRP3), basal areas between11.8 m2ha-1(DRP2) and 31.6 m2ha-1(DRP3). The average diameters were between 5.7 cm(DRP3) and 9.6 cm(DRP2). Measurements in September 2016 confirmed the rapid response of silver fir to cleaning-respacing.The best results in average diameter increments and basal area between 2012 and 2016 were in DRP2: 3.7 cm(36.4%) and 7.7 m2ha-1(85.0%) respectively. The largest diameter trees in 2012 were the best growers, and a strong linear correlation between the initial diameter of the remaining trees and their increment was established. Natural dieback of trees occurred only in DRP3(8.6%). The selection of crop trees based on the vigour, quality, and spacing criteria during cleaning-respacing was possible as individuals stood out in terms of vigour and early diameter growth. An issue encountered in DRP1 and DRP2 was the occurrence of epicormic shoots, especially on less vigorous individuals with small crowns. However, four years after cleaning-respacing, these branches are small and do not significantly affect the wood quality.展开更多
In this paper we refer to equations of motion for the single Stokes pulse from the nonlinear optics, called the Stokes pulse system. A fractional-order model with Caputo derivative associated to Stokes pulse system (c...In this paper we refer to equations of motion for the single Stokes pulse from the nonlinear optics, called the Stokes pulse system. A fractional-order model with Caputo derivative associated to Stokes pulse system (called the fractional Stokes pulse system) is proposed. The existence and uniqueness of solution of initial value problem for this fractional system are proved. The dynamic behavior for a special fractional Stokes pulse system is investigated, including: the fractional stability, the stabilization problem using suitable linear controls and the numerical integration based on fractional Euler method.展开更多
The article follows an analysis critical of the human rights convention from the perspective of abortion and euthanasia,bringing arguments for and against the right to life,starting at conception and to the final phas...The article follows an analysis critical of the human rights convention from the perspective of abortion and euthanasia,bringing arguments for and against the right to life,starting at conception and to the final phase of a human being.展开更多
The Pryce(e)spin and position operators of the quantum theory of Dirac's free field were re-defined and studied recently with the help of a new spin symmetry and suitable spectral representations[Eur.Phys.J.C 82,1...The Pryce(e)spin and position operators of the quantum theory of Dirac's free field were re-defined and studied recently with the help of a new spin symmetry and suitable spectral representations[Eur.Phys.J.C 82,1073(2022)].This approach is generalized here,associating a pair of integral operators acting directly on particle and antiparticle wave spinors in momentum representation to any integral operator in configuration representation,acting on mode spinors.This framework allows an effective quantization procedure,giving a large set of one-particle operators with physical meaning as the spin and orbital parts of the isometry generators,the Pauli-Lubanski and position operators,or other spin-type operators proposed to date.Special attention is paid to the operators that mix the particle and antiparticle sectors whose off-diagonal associated operators have oscillating terms producing Zitterbevegung.The principal operators of this type,including the usual coordinate operator,are derived here for the first time.As an application,it is shown that an apparatus measuring these new observables may prepare and detect oneparticle wave packets moving uniformly without Zitterbewegung or spin dynamics,spreading in time normally as any other relativistic or even non-relativistic wave packet.展开更多
Shorelines are vulnerable to anthropogenic activities including urbanization,land reclamation and sediment loading.Shoreline changes may be a reflection of the degradation of coastal ecosystems because of human activi...Shorelines are vulnerable to anthropogenic activities including urbanization,land reclamation and sediment loading.Shoreline changes may be a reflection of the degradation of coastal ecosystems because of human activities.Understanding the shoreline dynamics is,therefore,a topic of global concern.Earth observation data,such as multi-temporal satellite images,are an important resource for assessing changes in coastal ecosystems.In this research,we used Google Earth Engine(GEE)to monitor and map historical shoreline dynamics in the Hangzhou Bay in China where the Qiantang River flows into the East China Sea.Specifically,we aimed to capture and quantify both the spatial and temporal shoreline changes and to assess the link between anthropogenic activities and shoreline changes on the integrity of this coastal area.We implemented a Tasselled Cap analysis(TCA)on Landsat imagery from 1985 to 2018 in GEE to calculate the wetness coefficient.We then applied Otsu method for automatic image thresholding on the wetness coefficient to detect waterbodies and shoreline changes.Further,we adopted the nighttime light data from the Defense Meteorological Satellite Program’s Operational Linescan System(DMSP-OLS)from 1992 to 2013 as a proxy of human activities.The results show that in the hotspot areas,the shoreline has moved by more than 5 km in the last decades,accounting for approximately 900 km^(2) of land accretion.Within this area,the human activity,indicated by the intensity of nighttime light,increased significantly.The results of this work reveal the influence of human activities on the shoreline dynamics and can support policies that promote the sustainable use and conservation of coastal environments.Our methodology can be transferred and applied to other coastal zones in various regions and scaled up to larger areas.展开更多
The kinematics on spatially flat FLRW spacetimes is presented for the first time in local charts with physical coordinates,i.e.,the cosmic time and proper Cartesian space coordinates of Painlevé-type.It is shown ...The kinematics on spatially flat FLRW spacetimes is presented for the first time in local charts with physical coordinates,i.e.,the cosmic time and proper Cartesian space coordinates of Painlevé-type.It is shown that there exists a conserved momentum that determines the form of the covariant four-momentum on geodesics in terms of physical coordinates.Moreover,with the help of this conserved momentum,the peculiar momentum can be defined,thus separating the peculiar and recessional motions without ambiguity.It is shown that the energy and peculiar momentum satisfy the mass-shell condition of special relativity while the recessional momentum does not produce energy.In this framework,the measurements of the kinetic quantities along geodesics performed by different observers are analyzed,pointing out an energy loss of the massive particles similar to that producing the photon redshift.The examples of the kinematics on the de Sitter expanding universe and a new Milne-type spacetime are extensively analyzed.展开更多
This article analyses the literature regarding the value of computer-assisted systems in esogastroduodenoscopy-quality monitoring and the assessment of gastric lesions.Current data show promising results in upper-endo...This article analyses the literature regarding the value of computer-assisted systems in esogastroduodenoscopy-quality monitoring and the assessment of gastric lesions.Current data show promising results in upper-endoscopy quality control and a satisfactory detection accuracy of gastric premalignant and malignant lesions,similar or even exceeding that of experienced endoscopists.Moreover,artificial systems enable the decision for the best treatment strategies in gastriccancer patient care,namely endoscopic vs surgical resection according to tumor depth.In so doing,unnecessary surgical interventions would be avoided whilst providing a better quality of life and prognosis for these patients.All these performance data have been revealed by numerous studies using different artificial intelligence(AI)algorithms in addition to white-light endoscopy or novel endoscopic techniques that are available in expert endoscopy centers.It is expected that ongoing clinical trials involving AI and the embedding of computer-assisted diagnosis systems into endoscopic devices will enable real-life implementation of AI endoscopic systems in the near future and at the same time will help to overcome the current limits of the computer-assisted systems leading to an improvement in performance.These benefits should lead to better diagnostic and treatment strategies for gastric-cancer patients.Furthermore,the incorporation of AI algorithms in endoscopic tools along with the development of large electronic databases containing endoscopic images might help in upper-endoscopy assistance and could be used for telemedicine purposes and second opinion for difficult cases.展开更多
In the past years smart homes solutions have become more and more popular with the introduction of a high number of both Internet of Things(IoT)applications and smart devices.Home automation and security systems marke...In the past years smart homes solutions have become more and more popular with the introduction of a high number of both Internet of Things(IoT)applications and smart devices.Home automation and security systems market is in a continuous growth,traditional security systems are evolving fast,and more and more people choose Smart home solutions.In this paper,we propose two IoT based systems in the context of Smart homes:qToggle for multiple home automation,and MotionEyeOS,a video surveillance OS for single-board computers.Most qToggle devices are based on ESP8266/ESP8285 chips or on Raspberry Pi boards and smart sensors,while MotionEye uses Raspberry Pi boards.展开更多
Gastrointestinal infection is a leading cause of gut diseases attracting global health concerns.The emerging antimicrobial resistance in enteric pathogens drives the search of viable and renewable alternatives to anti...Gastrointestinal infection is a leading cause of gut diseases attracting global health concerns.The emerging antimicrobial resistance in enteric pathogens drives the search of viable and renewable alternatives to antibiotics for the health of both human beings and animals.Spore-forming probiotic Bacillus have received extensively interests for their multiple health benefits,including the restoration of microbiota dysbiosis and the reduction of drug-resistant pathogens.These promising benefits are mainly attributed to the activity of structurally diverse Bacillus-derived metabolites,such as antibacterial compounds,short-chain fatty acids,and other small molecules.Such metabolites show the capacity to directly target either the individual or community of bacterial pathogens,and to potentiate both host cells and gut microbiota.The better understanding of the mechanisms by which probiotic Bacillus and the metabolites modulate the metabolism of hosts and microbiota will advance the screening and development of probiotic Bacillus.In this review,we discuss the interaction among probiotic Bacillus,microbiota and host,and summarize the Bacillus-derived metabolites that act as key players in such interactions,shedding light on the mechanistic understanding of probiotic Bacillus against enteric bacterial infections.展开更多
文摘AIM: To compare the liver stiffness (LS) measurement by transient elastography (TE) to the liver biopsy (LB)-considered the "gold standard" in the evaluation of patients with chronic hepatitis C. METHODS: During a period of 12 mo, we evaluated 199 consecutive patients with chronic hepatitis due to hepatitis C virus (HCV), in which LB and LS assessments (by means of TE) were performed during the same session. RESULTS: Out of 199 patients, a valid measurement of the LS could not be obtained in 8. The mean value of LS in the cohort of 191 valid measurements was 8.45 ± 4.96 kPa, ranging from 2.3 to 38 kPa. The mean value of LS in patients with signifi cant fi brosis at biopsy (161 patients with F ≥ 2 according to Metavir) was 9.02 ± 5.15 kPa, significantly higher than in patients with no or mild fi brosis (30 patients with F < 2 Metavir): 5.39 ± 1.81 kPa (P < 0.0001). For a cut- off value of 6.8 kPa, the LS had a PPV of 98%, a NPV of 30.1%, a sensitivity of 59.6% and a specificity of 93.3% for the presence of signifi cant fi brosis (at least F2 Metavir), with a diagnostic performance of 77.3% (AUROC 0.773). Using this cut-off value, we reached the best discrimination between absence of fibrosis/ mild fibrosis (F < 2 Metavir) and the presence ofmoderate to severe fi brosis (F ≥ 2 Metavir). CONCLUSION: In patients with chronic hepatitis due to HCV, a cut-off value of 6.8 kPa measured by TE can differentiate between significant fibrosis and absent or mild fi brosis, with a PPV of 98%, a NPV of 30.1%, a sensitivity of 59.6%, a specificity of 93.3%, and a diagnostic performance of 77.3%.
文摘AIM:To determine whether acoustic radiation force impulse(ARFI) elastography is a reliable method for predicting fibrosis severity in patients with chronic hepatitis C virus(HCV) hepatitis.METHODS:We performed a multicenter study including 274 subjects with HCV chronic hepatitis in which we compared ARFI with liver biopsy(LB).In each patient we performed LB(evaluated according to the Metavir score) and ARFI measurements(using a Siemens Acuson S2000TM ultrasound system:10 valid measurements were performed and median values were calculated and expressed in meters/second(m/s).RESULTS:A direct,strong,correlation(Spearman r = 0.707) was found between ARFI measurements and fibrosis(P < 0.0001).For predicting the presence of fibrosis(F ≥ 1 Metavir),significant fibrosis(F ≥ 2),severe fibrosis(F ≥ 3) and cirrhosis(F = 4),the cutoff values of 1.19,1.21,1.58 and 1.82 m/s were determined,respectively,liver stiffness measurements had 73%,84%,84% and 91% Se respectively;93%,91%,94%,90% Sp,respectively;with AUROCs of 0.880,0.893,0.908 and 0.937,respectively.CONCLUSION:ARFI measurement is a reliable method for predicting the severity of fibrosis in HCV
文摘Pancreatic cancer(PC)has a low incidence rate but a high mortality,with patients often in the advanced stage of the disease at the time of the first diagnosis.If detected,early neoplastic lesions are ideal for surgery,offering the best prognosis.Preneoplastic lesions of the pancreas include pancreatic intraepithelial neoplasia and mucinous cystic neoplasms,with intraductal papillary mucinous neoplasms being the most commonly diagnosed.Our study focused on predicting PC by identifying early signs using noninvasive techniques and artificial intelligence(AI).A systematic English literature search was conducted on the PubMed electronic database and other sources.We obtained a total of 97 studies on the subject of pancreatic neoplasms.The final number of articles included in our study was 44,34 of which focused on the use of AI algorithms in the early diagnosis and prediction of pancreatic lesions.AI algorithms can facilitate diagnosis by analyzing massive amounts of data in a short period of time.Correlations can be made through AI algorithms by expanding image and electronic medical records databases,which can later be used as part of a screening program for the general population.AI-based screening models should involve a combination of biomarkers and medical and imaging data from different sources.This requires large numbers of resources,collaboration between medical practitioners,and investment in medical infrastructures.
文摘Domestic cats represent one of the most common sources of indoor allergens.All over the world,many households own cats,whose allergens are persistent and widespread.Cat allergy itself is frequent,and its symptoms vary from rhinoconjunctivitis to life-threatening asthma.In vitro diagnosis using precision medicine allergy immunoassays is important because natural cat dander extracts may differ in quality and quantity of some of the individual allergen components and other molecules.In the component-resolved diagnosis of cat allergy,singleplex and multiplex specific immunoglobulin(Ig)E assays include use of the cat-specific major allergen,secretoglobin Fel d 1(as a species-specific molecule),other allergen components(such as lipocalins Fel d 4,cross-reacting with other animal similar molecules,and Fel d 7,present in small quantities in natural extracts),and serum albumin Fel d 2(related to the cat-pork syndrome).IgA Fel d 5 and IgM Fel d 6 are not available as allergen components in the current commercial IgE immunoassays,but they may impair the in vitro diagnostic evaluation of cat allergy because galactose-α1,3-galactose is an IgE-binding epitope of these native feline allergens.The benefits of molecular-based cat allergy diagnosis are continually evaluated,as the role of recombinant allergen components already known is detailed and new other molecules of interest may be discovered in the future.
文摘Black locust(Robinia pseudoacacia L.) was the first North-American tree species imported to Europe at the beginning of the seventeenth century. It is commonly planted worldwide because of its adaptability to environmental stresses, its valuable wood, easy propagation, frequent and abundant seed production, excellent coppicing,high seedling survival, and relatively high wood yield. In Europe, Romania and Hungary have the most highly-developed black locust growing techniques and experiences.As a result of increasing interest in black locust in many countries, this review aims to provide a comprehensive overview of state-of-the-art site requirements, propagation, improvement and management(including growth and yield as well as use in energy plantations).
文摘Starting with Faraday’s law of electromagnetic induction in 1831,electric(electromagnetic)machines have been developed ever since as“assembles”of electric and magnetic coupled circuits that convert mechanical to electrical energy(in generators)and vice versa(in motors),via magnetic energy storage.Generators and motors are reversible.The Maxwell four equations(laws)later in 19th Century have prompted the rapid development of all basic(DC.brush and travelling field AC machines by 1900.Then by 1930 AC(alternating current)power(energy)systems evolved by connecting in parallel electric synchronous generators(with voltage boost and buck electric transformers for efficient AC power transmission lines)of rather constant frequency and voltage,driven by turbines(prime movers)that harness fossil(coal,gas or nuclear fuels),thermal or hydro energy.The last 50 years have witnessed a dramatic extension of generators power/unit,renewable energy generators and of variable speed AC motor drives in applications with variable output such as ventilators,pumps compressors,conveyors,orr-mills,electric transport(mobility),industrial automation,robotics,home appliances and info-gadgets.This formidable development,required by the need of more but cleaner energy,was mainly driven by power electronics,better materials,better modeling,design methodologies and digital control.This humble inaugural overview attempts to combine a brief history of electrical generators and motors with recent progress and trends in their design and control,for representative applications.
文摘This paper discusses the early silviculture of silver fir(Abies alba Mill.), a major softwood in Romania covering more than 294,000 ha. Three research plots(DRP1, DRP2 and DRP3) were established in a 25-year-old silver fir-dominated stand in May 2012. In DRP1 and DRP2, heavy cleaning-respacing were carried out while DRP3 was kept as a control. After the treatments in 2012,the plots had stocking between 1470 trees ha-1(DRP2) and10,030 trees ha-1(DRP3), basal areas between11.8 m2ha-1(DRP2) and 31.6 m2ha-1(DRP3). The average diameters were between 5.7 cm(DRP3) and 9.6 cm(DRP2). Measurements in September 2016 confirmed the rapid response of silver fir to cleaning-respacing.The best results in average diameter increments and basal area between 2012 and 2016 were in DRP2: 3.7 cm(36.4%) and 7.7 m2ha-1(85.0%) respectively. The largest diameter trees in 2012 were the best growers, and a strong linear correlation between the initial diameter of the remaining trees and their increment was established. Natural dieback of trees occurred only in DRP3(8.6%). The selection of crop trees based on the vigour, quality, and spacing criteria during cleaning-respacing was possible as individuals stood out in terms of vigour and early diameter growth. An issue encountered in DRP1 and DRP2 was the occurrence of epicormic shoots, especially on less vigorous individuals with small crowns. However, four years after cleaning-respacing, these branches are small and do not significantly affect the wood quality.
文摘In this paper we refer to equations of motion for the single Stokes pulse from the nonlinear optics, called the Stokes pulse system. A fractional-order model with Caputo derivative associated to Stokes pulse system (called the fractional Stokes pulse system) is proposed. The existence and uniqueness of solution of initial value problem for this fractional system are proved. The dynamic behavior for a special fractional Stokes pulse system is investigated, including: the fractional stability, the stabilization problem using suitable linear controls and the numerical integration based on fractional Euler method.
文摘The article follows an analysis critical of the human rights convention from the perspective of abortion and euthanasia,bringing arguments for and against the right to life,starting at conception and to the final phase of a human being.
文摘The Pryce(e)spin and position operators of the quantum theory of Dirac's free field were re-defined and studied recently with the help of a new spin symmetry and suitable spectral representations[Eur.Phys.J.C 82,1073(2022)].This approach is generalized here,associating a pair of integral operators acting directly on particle and antiparticle wave spinors in momentum representation to any integral operator in configuration representation,acting on mode spinors.This framework allows an effective quantization procedure,giving a large set of one-particle operators with physical meaning as the spin and orbital parts of the isometry generators,the Pauli-Lubanski and position operators,or other spin-type operators proposed to date.Special attention is paid to the operators that mix the particle and antiparticle sectors whose off-diagonal associated operators have oscillating terms producing Zitterbevegung.The principal operators of this type,including the usual coordinate operator,are derived here for the first time.As an application,it is shown that an apparatus measuring these new observables may prepare and detect oneparticle wave packets moving uniformly without Zitterbewegung or spin dynamics,spreading in time normally as any other relativistic or even non-relativistic wave packet.
基金The work is partially funded by the Austrian Science Fund(FWF)through the Doctoral College GIScience at the University of Salzburg(DK W1237-N23).
文摘Shorelines are vulnerable to anthropogenic activities including urbanization,land reclamation and sediment loading.Shoreline changes may be a reflection of the degradation of coastal ecosystems because of human activities.Understanding the shoreline dynamics is,therefore,a topic of global concern.Earth observation data,such as multi-temporal satellite images,are an important resource for assessing changes in coastal ecosystems.In this research,we used Google Earth Engine(GEE)to monitor and map historical shoreline dynamics in the Hangzhou Bay in China where the Qiantang River flows into the East China Sea.Specifically,we aimed to capture and quantify both the spatial and temporal shoreline changes and to assess the link between anthropogenic activities and shoreline changes on the integrity of this coastal area.We implemented a Tasselled Cap analysis(TCA)on Landsat imagery from 1985 to 2018 in GEE to calculate the wetness coefficient.We then applied Otsu method for automatic image thresholding on the wetness coefficient to detect waterbodies and shoreline changes.Further,we adopted the nighttime light data from the Defense Meteorological Satellite Program’s Operational Linescan System(DMSP-OLS)from 1992 to 2013 as a proxy of human activities.The results show that in the hotspot areas,the shoreline has moved by more than 5 km in the last decades,accounting for approximately 900 km^(2) of land accretion.Within this area,the human activity,indicated by the intensity of nighttime light,increased significantly.The results of this work reveal the influence of human activities on the shoreline dynamics and can support policies that promote the sustainable use and conservation of coastal environments.Our methodology can be transferred and applied to other coastal zones in various regions and scaled up to larger areas.
文摘The kinematics on spatially flat FLRW spacetimes is presented for the first time in local charts with physical coordinates,i.e.,the cosmic time and proper Cartesian space coordinates of Painlevé-type.It is shown that there exists a conserved momentum that determines the form of the covariant four-momentum on geodesics in terms of physical coordinates.Moreover,with the help of this conserved momentum,the peculiar momentum can be defined,thus separating the peculiar and recessional motions without ambiguity.It is shown that the energy and peculiar momentum satisfy the mass-shell condition of special relativity while the recessional momentum does not produce energy.In this framework,the measurements of the kinetic quantities along geodesics performed by different observers are analyzed,pointing out an energy loss of the massive particles similar to that producing the photon redshift.The examples of the kinematics on the de Sitter expanding universe and a new Milne-type spacetime are extensively analyzed.
文摘This article analyses the literature regarding the value of computer-assisted systems in esogastroduodenoscopy-quality monitoring and the assessment of gastric lesions.Current data show promising results in upper-endoscopy quality control and a satisfactory detection accuracy of gastric premalignant and malignant lesions,similar or even exceeding that of experienced endoscopists.Moreover,artificial systems enable the decision for the best treatment strategies in gastriccancer patient care,namely endoscopic vs surgical resection according to tumor depth.In so doing,unnecessary surgical interventions would be avoided whilst providing a better quality of life and prognosis for these patients.All these performance data have been revealed by numerous studies using different artificial intelligence(AI)algorithms in addition to white-light endoscopy or novel endoscopic techniques that are available in expert endoscopy centers.It is expected that ongoing clinical trials involving AI and the embedding of computer-assisted diagnosis systems into endoscopic devices will enable real-life implementation of AI endoscopic systems in the near future and at the same time will help to overcome the current limits of the computer-assisted systems leading to an improvement in performance.These benefits should lead to better diagnostic and treatment strategies for gastric-cancer patients.Furthermore,the incorporation of AI algorithms in endoscopic tools along with the development of large electronic databases containing endoscopic images might help in upper-endoscopy assistance and could be used for telemedicine purposes and second opinion for difficult cases.
文摘In the past years smart homes solutions have become more and more popular with the introduction of a high number of both Internet of Things(IoT)applications and smart devices.Home automation and security systems market is in a continuous growth,traditional security systems are evolving fast,and more and more people choose Smart home solutions.In this paper,we propose two IoT based systems in the context of Smart homes:qToggle for multiple home automation,and MotionEyeOS,a video surveillance OS for single-board computers.Most qToggle devices are based on ESP8266/ESP8285 chips or on Raspberry Pi boards and smart sensors,while MotionEye uses Raspberry Pi boards.
基金supported by the National Key Research and Development Program of China(2022YFD1801600).
文摘Gastrointestinal infection is a leading cause of gut diseases attracting global health concerns.The emerging antimicrobial resistance in enteric pathogens drives the search of viable and renewable alternatives to antibiotics for the health of both human beings and animals.Spore-forming probiotic Bacillus have received extensively interests for their multiple health benefits,including the restoration of microbiota dysbiosis and the reduction of drug-resistant pathogens.These promising benefits are mainly attributed to the activity of structurally diverse Bacillus-derived metabolites,such as antibacterial compounds,short-chain fatty acids,and other small molecules.Such metabolites show the capacity to directly target either the individual or community of bacterial pathogens,and to potentiate both host cells and gut microbiota.The better understanding of the mechanisms by which probiotic Bacillus and the metabolites modulate the metabolism of hosts and microbiota will advance the screening and development of probiotic Bacillus.In this review,we discuss the interaction among probiotic Bacillus,microbiota and host,and summarize the Bacillus-derived metabolites that act as key players in such interactions,shedding light on the mechanistic understanding of probiotic Bacillus against enteric bacterial infections.
