Annual haze in Northern Thailand has become increasingly severe,impacting health and the environment.How-ever,the sources of the haze remain poorly quantified due to limited observational data on aerosol molecular tra...Annual haze in Northern Thailand has become increasingly severe,impacting health and the environment.How-ever,the sources of the haze remain poorly quantified due to limited observational data on aerosol molecular tracers.This study comprehensively investigates chemical composition of PM_(2.5),including both inorganic and organic compounds throughout haze and post-haze periods in 2019 at a rural site of Northern Thailand.Average PM_(2.5) concentrations during haze and post-haze period were 87±36 and 21±11μg/m^(3),respectively.Organic matter was the dominant contributor in PM_(2.5) mass,followed by water soluble inorganic ions and mineral dust.Molecular markers,including levoglucosan,dehydroabietic acid,and 4-nitrocatechol,and ions(Cl^(-),and K^(+)),were used to characterize low haze(PM_(2.5)<100μg/m^(3))and episodic haze(PM_(2.5)>100μg/m^(3)).Low haze is associated with local aerosols from agricultural waste burning,while episodic haze is linked to aged aerosols from mixed agricultural waste,softwood,and hardwood burning.Source apportionment incorporating these molecular markers in receptor modelling(Positive matrix factorization),identified three distinct biomass burning sources:mixed,local,and aged biomass burnings,contributing 31,19 and 13%of PM_(2.5) during haze period.During post-haze period,contributions shifted,with local biomass burning(32%)comparable to secondary sulfate(34%)and mixed dust and traffic sources(26%).These findings demonstrate that both regional and local sources con-tribute to severe haze,highlighting the need for integrated policies for cross-border cooperation as well as stricter regulations to reduce biomass burning in Northern Thailand and Southeast Asia.展开更多
Background:Corneal scarring following bacterial keratitis,particularly from Pseudomonas infections,poses significant challenges in ophthalmic care.Current treatments often fall short in effectively reducing corneal ha...Background:Corneal scarring following bacterial keratitis,particularly from Pseudomonas infections,poses significant challenges in ophthalmic care.Current treatments often fall short in effectively reducing corneal haze and restoring vision.To our knowledge,this is the first report documenting the use of topical losartan,an angiotensin II receptor antagonist known to inhibit the transforming growth factor-β(TGF-β)pathway,for treating corneal haze resulting from bacterial keratitis.Case Description:A 30-year-old male presented with a persistent corneal scar in his right eye,178 days post-Pseudomonas keratitis.Despite a prolonged course of topical corticosteroids,his best-corrected visual acuity(BCVA)stabilized at 20/40 with a hybrid contact lens over a 2-month period.Given the lack of improvement,we initiated treatment with topical losartan at a concentration of 0.8 mg/mL,administered six times daily.After 4 months of therapy,the patient’s BCVA improved to 20/25.Slit-lamp examination and corneal tomography revealed a significant reduction in corneal haze,indicating a positive response to the treatment.Conclusions:This case suggests that topical losartan may be a promising therapeutic option for reducing corneal opacity following bacterial keratitis by inhibiting the TGF-βpathway.However,further clinical studies are necessary to confirm its efficacy and safety in broader patient populations.展开更多
License plate recognition in haze-affected images is challenging due to feature distortions such as blurring and elongation,which lead to pixel displacements.This article introduces a Displacement Region Recognition M...License plate recognition in haze-affected images is challenging due to feature distortions such as blurring and elongation,which lead to pixel displacements.This article introduces a Displacement Region Recognition Method(DR2M)to address such a problem.This method operates on displaced features compared to the training input observed throughout definite time frames.The technique focuses on detecting features that remain relatively stable under haze,using a frame-based analysis to isolate edges minimally affected by visual noise.The edge detection failures are identified using a bilateral neural network through displaced feature training.The training converges bilaterally towards the minimum edges from the maximum region.Thus,the training input and detected edges are used to identify the displacement between observed image frames to extract and differentiate the license plate region from the other vehicle regions.The proposed method maps the similarity feature between the detected and identified vehicle regions.This aids in leveraging the plate recognition precision with a high F1 score.Thus,this technique achieves a 10.27%improvement in identification precision,a 10.57%increase in F1 score,and a 9.73%reduction in false positive rate compared to baseline methods under maximum displacement conditions caused by haze.The technique attains an identification precision of 95.68%,an F1 score of 94.68%,and a false positive rate of 4.32%,indicating robust performance under haze-affected settings.展开更多
Based on meteorology and environment monitoring data in January,2008 in Liaoning central region,a typical haze weather process was analyzed.The results showed that haze was formed due to the stable weather condition i...Based on meteorology and environment monitoring data in January,2008 in Liaoning central region,a typical haze weather process was analyzed.The results showed that haze was formed due to the stable weather condition in the earth surface and upper air layer in Liaoning central region.Especially because that the weakening of atmospheric dispersion ability in the urban boundary layer that was 500 m under earth surface,caused the pollutant in the air can not disperse.Thus,it resulted in the deterioration of air quality,increase of concentration of particulate mass,and declination of visibility.And in the end,haze formed.展开更多
In January 2013, China suffered large-scale haze weather four times, affecting 30 cities in all. The average number of haze weather days in many regions was higher than the same period in every year since 1961. PM2.s,...In January 2013, China suffered large-scale haze weather four times, affecting 30 cities in all. The average number of haze weather days in many regions was higher than the same period in every year since 1961. PM2.s, which is defined as fine particulate matter with an aerodynamic diameter of 2.5 micrometers or less, is the main health hazard in the context of haze weather. It can carry large amounts of poisonous and harmful substances, and penetrate deep into the lungs and blood circulation through the respiratory tract, thereby affecting human health.展开更多
文摘Annual haze in Northern Thailand has become increasingly severe,impacting health and the environment.How-ever,the sources of the haze remain poorly quantified due to limited observational data on aerosol molecular tracers.This study comprehensively investigates chemical composition of PM_(2.5),including both inorganic and organic compounds throughout haze and post-haze periods in 2019 at a rural site of Northern Thailand.Average PM_(2.5) concentrations during haze and post-haze period were 87±36 and 21±11μg/m^(3),respectively.Organic matter was the dominant contributor in PM_(2.5) mass,followed by water soluble inorganic ions and mineral dust.Molecular markers,including levoglucosan,dehydroabietic acid,and 4-nitrocatechol,and ions(Cl^(-),and K^(+)),were used to characterize low haze(PM_(2.5)<100μg/m^(3))and episodic haze(PM_(2.5)>100μg/m^(3)).Low haze is associated with local aerosols from agricultural waste burning,while episodic haze is linked to aged aerosols from mixed agricultural waste,softwood,and hardwood burning.Source apportionment incorporating these molecular markers in receptor modelling(Positive matrix factorization),identified three distinct biomass burning sources:mixed,local,and aged biomass burnings,contributing 31,19 and 13%of PM_(2.5) during haze period.During post-haze period,contributions shifted,with local biomass burning(32%)comparable to secondary sulfate(34%)and mixed dust and traffic sources(26%).These findings demonstrate that both regional and local sources con-tribute to severe haze,highlighting the need for integrated policies for cross-border cooperation as well as stricter regulations to reduce biomass burning in Northern Thailand and Southeast Asia.
文摘Background:Corneal scarring following bacterial keratitis,particularly from Pseudomonas infections,poses significant challenges in ophthalmic care.Current treatments often fall short in effectively reducing corneal haze and restoring vision.To our knowledge,this is the first report documenting the use of topical losartan,an angiotensin II receptor antagonist known to inhibit the transforming growth factor-β(TGF-β)pathway,for treating corneal haze resulting from bacterial keratitis.Case Description:A 30-year-old male presented with a persistent corneal scar in his right eye,178 days post-Pseudomonas keratitis.Despite a prolonged course of topical corticosteroids,his best-corrected visual acuity(BCVA)stabilized at 20/40 with a hybrid contact lens over a 2-month period.Given the lack of improvement,we initiated treatment with topical losartan at a concentration of 0.8 mg/mL,administered six times daily.After 4 months of therapy,the patient’s BCVA improved to 20/25.Slit-lamp examination and corneal tomography revealed a significant reduction in corneal haze,indicating a positive response to the treatment.Conclusions:This case suggests that topical losartan may be a promising therapeutic option for reducing corneal opacity following bacterial keratitis by inhibiting the TGF-βpathway.However,further clinical studies are necessary to confirm its efficacy and safety in broader patient populations.
基金supported by the Princess Nourah bint Abdulrahman University Researchers Supporting Project number(PNURSP2025R848)Princess Nourah bint Abdulrahman University,Riyadh,Saudi Arabiathe Deanship of Scientific Research at Northern Border University,Arar,Saudi Arabia for funding this research work through the project number“NBU-FFR-2025-2932-09”.
文摘License plate recognition in haze-affected images is challenging due to feature distortions such as blurring and elongation,which lead to pixel displacements.This article introduces a Displacement Region Recognition Method(DR2M)to address such a problem.This method operates on displaced features compared to the training input observed throughout definite time frames.The technique focuses on detecting features that remain relatively stable under haze,using a frame-based analysis to isolate edges minimally affected by visual noise.The edge detection failures are identified using a bilateral neural network through displaced feature training.The training converges bilaterally towards the minimum edges from the maximum region.Thus,the training input and detected edges are used to identify the displacement between observed image frames to extract and differentiate the license plate region from the other vehicle regions.The proposed method maps the similarity feature between the detected and identified vehicle regions.This aids in leveraging the plate recognition precision with a high F1 score.Thus,this technique achieves a 10.27%improvement in identification precision,a 10.57%increase in F1 score,and a 9.73%reduction in false positive rate compared to baseline methods under maximum displacement conditions caused by haze.The technique attains an identification precision of 95.68%,an F1 score of 94.68%,and a false positive rate of 4.32%,indicating robust performance under haze-affected settings.
基金Supported by Liaoning Meteorology Bureau Scientific Research Fund (200808)China Meterological Administration Shenyang Atmospheric Science Research Bureau Scieatific Resarch Fund ProgramScientific Research Special Fund for Public Welfare Industry in 2008 (GYHY20080620)
文摘Based on meteorology and environment monitoring data in January,2008 in Liaoning central region,a typical haze weather process was analyzed.The results showed that haze was formed due to the stable weather condition in the earth surface and upper air layer in Liaoning central region.Especially because that the weakening of atmospheric dispersion ability in the urban boundary layer that was 500 m under earth surface,caused the pollutant in the air can not disperse.Thus,it resulted in the deterioration of air quality,increase of concentration of particulate mass,and declination of visibility.And in the end,haze formed.
文摘In January 2013, China suffered large-scale haze weather four times, affecting 30 cities in all. The average number of haze weather days in many regions was higher than the same period in every year since 1961. PM2.s, which is defined as fine particulate matter with an aerodynamic diameter of 2.5 micrometers or less, is the main health hazard in the context of haze weather. It can carry large amounts of poisonous and harmful substances, and penetrate deep into the lungs and blood circulation through the respiratory tract, thereby affecting human health.
