This paper highlights the crucial role of Indonesia’s GNSS receiver network in advancing Equatorial Plasma Bubble(EPB)studies in Southeast and East Asia,as ionospheric irregularities within EPB can disrupt GNSS signa...This paper highlights the crucial role of Indonesia’s GNSS receiver network in advancing Equatorial Plasma Bubble(EPB)studies in Southeast and East Asia,as ionospheric irregularities within EPB can disrupt GNSS signals and degrade positioning accuracy.Managed by the Indonesian Geospatial Information Agency(BIG),the Indonesia Continuously Operating Reference Station(Ina-CORS)network comprises over 300 GNSS receivers spanning equatorial to southern low-latitude regions.Ina-CORS is uniquely situated to monitor EPB generation,zonal drift,and dissipation across Southeast Asia.We provide a practical tool for EPB research,by sharing two-dimensional rate of Total Electron Content(TEC)change index(ROTI)derived from this network.We generate ROTI maps with a 10-minute resolution,and samples from May 2024 are publicly available for further scientific research.Two preliminary findings from the ROTI maps of Ina-CORS are noteworthy.First,the Ina-CORS ROTI maps reveal that the irregularities within a broader EPB structure persist longer,increasing the potential for these irregularities to migrate farther eastward.Second,we demonstrate that combined ROTI maps from Ina-CORS and GNSS receivers in East Asia and Australia can be used to monitor the development of ionospheric irregularities in Southeast and East Asia.We have demonstrated the combined ROTI maps to capture the development of ionospheric irregularities in the Southeast/East Asian sector during the G5 Geomagnetic Storm on May 11,2024.We observed simultaneous ionospheric irregularities in Japan and Australia,respectively propagating northwestward and southwestward,before midnight,whereas Southeast Asia’s equatorial and low-latitude regions exhibited irregularities post-midnight.By sharing ROTI maps from Indonesia and integrating them with regional GNSS networks,researchers can conduct comprehensive EPB studies,enhancing the understanding of EPB behavior across Southeast and East Asia and contributing significantly to ionospheric research.展开更多
The straight channel optical waveguide coated with the SnO_(2) nanoparticle is studied as an all-optical humidity sensor.The proposed sensor shows that the transmission loss of the waveguide increases with increasing ...The straight channel optical waveguide coated with the SnO_(2) nanoparticle is studied as an all-optical humidity sensor.The proposed sensor shows that the transmission loss of the waveguide increases with increasing relative humidity(RH)from 56%to 90%with very good repeatability.The sensitivity to changes in relative humidity is~2 dB/%RH.The response time of the humidity sensor is 2.5 s,and the recovery time is 3.5 s.The response to humidity can be divided into 3 different regions,which are correlated to the degree of water adsorption in the SnO_(2) nanoparticle layer.Compared with the previous all-optical humidity sensor based on SnO_(2),the proposed sensor exhibits more rapid response,simpler fabrication process,and higher sensitivity.The proposed sensor has a potential application in the long distance,remote agriculture,and biological humidity sensing.展开更多
Background:Erythrina suberosa(E.suberosa)Roxb.also known as corky coral tree is used as a folklore medicine to treat ulcers and piles.This study explored the phytochemical profiles of methanol and dichloromethane(DCM)...Background:Erythrina suberosa(E.suberosa)Roxb.also known as corky coral tree is used as a folklore medicine to treat ulcers and piles.This study explored the phytochemical profiles of methanol and dichloromethane(DCM)extracts from the aerial,root,and flower parts of E.suberosa.Method:Total bioactive contents,high-performance liquid chromatography array(HPLC-PDA)polyphenolic quantification,and ultra-high performance liquid chromatography-mass spectrometry(UHPLC-MS)analysis were used to evaluate the phytochemical profile.Biological potential was evaluated by determining their antioxidant(DPPH,ABTS,FRAP,CUPRAC,Phosphomolybdenum,and metal chelating)and enzyme inhibitory(cholinesterase,amylase,glucosidase,and tyrosinase)effects.Results:The phenolic(46.26 mg GAE/g extract)and flavonoid(32.46 mg QE/g extract)contents were found to be highest in the methanolic extract of roots(EsR-M).HPLC-PDA analysis determined the presence of numerous bioactive compounds,including catechin,syringic acid,p-hydroxy benzoic acid,gallic acid,vanillic acid,epicatechin,rutin,chlorogenic acid,carvacrol,sinapinic acid,and naringenin in considerable amounts.A total of 143 phytochemicals,belonging to phenolic,flavonoid,coumarin,terpenoid,chalcone,saponin,and glycoside classes,were tentatively identified by UHPLC-MS analysis.Aerial methanolic extract(EsA-M)exhibited highest radical scavenging(DPPH 86.81 mgTE/g extract,ABTS 245.17 mgTE/g extract)as well as reducing potential(FRAP 177.12 mgTE/g extract,CUPRAC 177.12 mgTE/g extract).Likewise,it was also noted to be most active for BChE(5.70 mg GALAE/g extract)and tyrosinase inhibition(148.35 mg KAE/g extract).While,roots-DCM extract(EsR-D)presented considerable inhibition for AChE(4.69 mg GALAE/g extract)and amylase(0.81 mmol ACAE/g extract)enzymes.Coreopsin,davallioside A,and isovitexin were docked to tyrosinase to depict possible interaction.Conclusion:This study has established baseline data on the biological and phytochemical profile of E.suberosa which was found to possess antioxidant and enzym展开更多
The current research work aimed at the phytochemical,biological,and in-silico properties of hydro-methanol extract and n-hexane fraction of Crateva adansonii aerial parts.Total bioactive content and UHPLC-MS analysis ...The current research work aimed at the phytochemical,biological,and in-silico properties of hydro-methanol extract and n-hexane fraction of Crateva adansonii aerial parts.Total bioactive content and UHPLC-MS analysis were used to determine the phytochemical composition.Regarding biological activities,antioxidant(DPPH,ABTS,FRAP,CUPRAC,phosphomolybdenum,and metal chelation)and enzyme inhibition(againstα-amylase,tyrosinase,acetylcholinesterase-AChE,and butyrylcholinesterase-BChE)activities were assessed.The hydro-methanol extract contained higher phenolic(28.09 mg GAE/g extract)and flavonoid(65.61 mg RE/g extract)contents,which might be correlated with the higher antioxidant potential of this extract.For the enzyme assays,the n-hexane fraction was most active against BChE andα-amylase,while the methanol extract presented higher inhibition values against AChE and tyrosinase enzymes.Likewise,different phytocompounds have been tentatively identified by UHPLC-MS of hydro-methanol extract;most of these belonged to phenolic and flavonoid classes.Furthermore,three important identified phytocompounds(isovitexin,robinetin 3-rutinoside,and luteolin 7-robinobioside),were selected for in-silico computational studies against the tyrosinase enzyme.The present investigation revealed that the studied extract/fraction of C.adansonii are likely sources of phytoconstituents identified through UHPLC-MS with considerable antioxidant and enzyme inhibitory properties.To conclude,the evaluated plant should be further investigated for the isolation of bioactive molecules which can be utilized in phytopharmaceuticals.展开更多
基金support received from Telkom University under the“Skema Penelitian Terapan Periode I Tahun Anggaran 2024”and the Memorandum of Understanding for Research Collaboration on Regional Ionospheric Observation(No:092/SAM3/TEDEK/2021)along with colleagues UAA and WPT.INM sincerely thanks the National Institute of Information and Communications Technology(NICT)International Exchange Program 2024−2025(No.2024−007)for their invaluable support for a one-year visiting research at Hokkaido University.
文摘This paper highlights the crucial role of Indonesia’s GNSS receiver network in advancing Equatorial Plasma Bubble(EPB)studies in Southeast and East Asia,as ionospheric irregularities within EPB can disrupt GNSS signals and degrade positioning accuracy.Managed by the Indonesian Geospatial Information Agency(BIG),the Indonesia Continuously Operating Reference Station(Ina-CORS)network comprises over 300 GNSS receivers spanning equatorial to southern low-latitude regions.Ina-CORS is uniquely situated to monitor EPB generation,zonal drift,and dissipation across Southeast Asia.We provide a practical tool for EPB research,by sharing two-dimensional rate of Total Electron Content(TEC)change index(ROTI)derived from this network.We generate ROTI maps with a 10-minute resolution,and samples from May 2024 are publicly available for further scientific research.Two preliminary findings from the ROTI maps of Ina-CORS are noteworthy.First,the Ina-CORS ROTI maps reveal that the irregularities within a broader EPB structure persist longer,increasing the potential for these irregularities to migrate farther eastward.Second,we demonstrate that combined ROTI maps from Ina-CORS and GNSS receivers in East Asia and Australia can be used to monitor the development of ionospheric irregularities in Southeast and East Asia.We have demonstrated the combined ROTI maps to capture the development of ionospheric irregularities in the Southeast/East Asian sector during the G5 Geomagnetic Storm on May 11,2024.We observed simultaneous ionospheric irregularities in Japan and Australia,respectively propagating northwestward and southwestward,before midnight,whereas Southeast Asia’s equatorial and low-latitude regions exhibited irregularities post-midnight.By sharing ROTI maps from Indonesia and integrating them with regional GNSS networks,researchers can conduct comprehensive EPB studies,enhancing the understanding of EPB behavior across Southeast and East Asia and contributing significantly to ionospheric research.
基金supported by the Ministry of Research,Technology&Higher Education of Indonesia with PMDSU scholarship fundingthe Malaysia Ministry of Higher Education(MOHE)(LRGS(2015)/NGOD/UM/KPT)。
文摘The straight channel optical waveguide coated with the SnO_(2) nanoparticle is studied as an all-optical humidity sensor.The proposed sensor shows that the transmission loss of the waveguide increases with increasing relative humidity(RH)from 56%to 90%with very good repeatability.The sensitivity to changes in relative humidity is~2 dB/%RH.The response time of the humidity sensor is 2.5 s,and the recovery time is 3.5 s.The response to humidity can be divided into 3 different regions,which are correlated to the degree of water adsorption in the SnO_(2) nanoparticle layer.Compared with the previous all-optical humidity sensor based on SnO_(2),the proposed sensor exhibits more rapid response,simpler fabrication process,and higher sensitivity.The proposed sensor has a potential application in the long distance,remote agriculture,and biological humidity sensing.
文摘Background:Erythrina suberosa(E.suberosa)Roxb.also known as corky coral tree is used as a folklore medicine to treat ulcers and piles.This study explored the phytochemical profiles of methanol and dichloromethane(DCM)extracts from the aerial,root,and flower parts of E.suberosa.Method:Total bioactive contents,high-performance liquid chromatography array(HPLC-PDA)polyphenolic quantification,and ultra-high performance liquid chromatography-mass spectrometry(UHPLC-MS)analysis were used to evaluate the phytochemical profile.Biological potential was evaluated by determining their antioxidant(DPPH,ABTS,FRAP,CUPRAC,Phosphomolybdenum,and metal chelating)and enzyme inhibitory(cholinesterase,amylase,glucosidase,and tyrosinase)effects.Results:The phenolic(46.26 mg GAE/g extract)and flavonoid(32.46 mg QE/g extract)contents were found to be highest in the methanolic extract of roots(EsR-M).HPLC-PDA analysis determined the presence of numerous bioactive compounds,including catechin,syringic acid,p-hydroxy benzoic acid,gallic acid,vanillic acid,epicatechin,rutin,chlorogenic acid,carvacrol,sinapinic acid,and naringenin in considerable amounts.A total of 143 phytochemicals,belonging to phenolic,flavonoid,coumarin,terpenoid,chalcone,saponin,and glycoside classes,were tentatively identified by UHPLC-MS analysis.Aerial methanolic extract(EsA-M)exhibited highest radical scavenging(DPPH 86.81 mgTE/g extract,ABTS 245.17 mgTE/g extract)as well as reducing potential(FRAP 177.12 mgTE/g extract,CUPRAC 177.12 mgTE/g extract).Likewise,it was also noted to be most active for BChE(5.70 mg GALAE/g extract)and tyrosinase inhibition(148.35 mg KAE/g extract).While,roots-DCM extract(EsR-D)presented considerable inhibition for AChE(4.69 mg GALAE/g extract)and amylase(0.81 mmol ACAE/g extract)enzymes.Coreopsin,davallioside A,and isovitexin were docked to tyrosinase to depict possible interaction.Conclusion:This study has established baseline data on the biological and phytochemical profile of E.suberosa which was found to possess antioxidant and enzym
文摘The current research work aimed at the phytochemical,biological,and in-silico properties of hydro-methanol extract and n-hexane fraction of Crateva adansonii aerial parts.Total bioactive content and UHPLC-MS analysis were used to determine the phytochemical composition.Regarding biological activities,antioxidant(DPPH,ABTS,FRAP,CUPRAC,phosphomolybdenum,and metal chelation)and enzyme inhibition(againstα-amylase,tyrosinase,acetylcholinesterase-AChE,and butyrylcholinesterase-BChE)activities were assessed.The hydro-methanol extract contained higher phenolic(28.09 mg GAE/g extract)and flavonoid(65.61 mg RE/g extract)contents,which might be correlated with the higher antioxidant potential of this extract.For the enzyme assays,the n-hexane fraction was most active against BChE andα-amylase,while the methanol extract presented higher inhibition values against AChE and tyrosinase enzymes.Likewise,different phytocompounds have been tentatively identified by UHPLC-MS of hydro-methanol extract;most of these belonged to phenolic and flavonoid classes.Furthermore,three important identified phytocompounds(isovitexin,robinetin 3-rutinoside,and luteolin 7-robinobioside),were selected for in-silico computational studies against the tyrosinase enzyme.The present investigation revealed that the studied extract/fraction of C.adansonii are likely sources of phytoconstituents identified through UHPLC-MS with considerable antioxidant and enzyme inhibitory properties.To conclude,the evaluated plant should be further investigated for the isolation of bioactive molecules which can be utilized in phytopharmaceuticals.
