The rapid advancement of nanotechnology has sparked much interest in applying nanoscale perovskite materials for photodetection applications.These materials are promising candidates for next-generation photodetectors(...The rapid advancement of nanotechnology has sparked much interest in applying nanoscale perovskite materials for photodetection applications.These materials are promising candidates for next-generation photodetectors(PDs)due to their unique optoelectronic properties and flexible synthesis routes.This review explores the approaches used in the development and use of optoelectronic devices made of different nanoscale perovskite architectures,including quantum dots,nanosheets,nanorods,nanowires,and nanocrystals.Through a thorough analysis of recent literature,the review also addresses common issues like the mechanisms underlying the degradation of perovskite PDs and offers perspectives on potential solutions to improve stability and scalability that impede widespread implementation.In addition,it highlights that photodetection encompasses the detection of light fields in dimensions other than light intensity and suggests potential avenues for future research to overcome these obstacles and fully realize the potential of nanoscale perovskite materials in state-of-the-art photodetection systems.This review provides a comprehensive overview of nanoscale perovskite PDs and guides future research efforts towards improved performance and wider applicability,making it a valuable resource for researchers.展开更多
Friction stir welding(FSW)is a relatively new welding technique that has significant advantages compared to the fusion welding techniques in joining non weld able alloys by fusion,such as aluminum alloys.Three FSW sea...Friction stir welding(FSW)is a relatively new welding technique that has significant advantages compared to the fusion welding techniques in joining non weld able alloys by fusion,such as aluminum alloys.Three FSW seams of AA6061-T6 plates were made us-ing different FSW parameters.The structure of the FSW seams was investigated using X-ray diffraction(XRD),scanning electron mi-croscope(SEM)and non destructive testing(NDT)techniques and their hardness was also measured.The dominated phase in the AA6061-T6 alloy and the FSW seams was theα-Al.The FSW seam had lower content of the secondary phases than the AA6061-T6 al-loy.The hardness of the FSW seams was decreased by about 30%compared to the AA6061-T6 alloy.The temperature distributions in the weld seams were also studied experimentally and numerically modeled and the results were in a good agreement.展开更多
Agricultural practices significantly contribute to greenhouse gas(GHG)emissions,necessitating cleaner production technologies to reduce environmental pressure and achieve sustainable maize production.Plastic film mulc...Agricultural practices significantly contribute to greenhouse gas(GHG)emissions,necessitating cleaner production technologies to reduce environmental pressure and achieve sustainable maize production.Plastic film mulching is commonly used in the Loess Plateau region.Incorporating slow-release fertilizers as a replacement for urea within this practice can reduce nitrogen losses and enhance crop productivity.Combining these techniques represents a novel agricultural approach in semi-arid areas.However,the impact of this integration on soil carbon storage(SOCS),carbon footprint(CF),and economic benefits has received limited research attention.Therefore,we conducted an eight-year study(2015-2022)in the semi-arid northwestern region to quantify the effects of four treatments[urea supplied without plastic film mulching(CK-U),slow-release fertilizer supplied without plastic film mulching(CK-S),urea supplied with plastic film mulching(PM-U),and slow-release fertilizer supplied with plastic film mulching(PM-S)]on soil fertility,economic and environmental benefits.The results revealed that nitrogen fertilizer was the primary contributor to total GHG emissions(≥71.97%).Compared to other treatments,PM-S increased average grain yield by 12.01%-37.89%,water use efficiency by 9.19%-23.33%,nitrogen accumulation by 27.07%-66.19%,and net return by 6.21%-29.57%.Furthermore,PM-S decreased CF by 12.87%-44.31%and CF per net return by 14.25%-41.16%.After eight years,PM-S increased SOCS(0-40 cm)by 2.46%,while PM-U decreased it by 7.09%.These findings highlight the positive effects of PM-S on surface soil fertility,economic gains,and environmental benefits in spring maize production on the Loess Plateau,underscoring its potential for widespread adoption and application.展开更多
For the first time,the linear and nonlinear vibrations of composite rectangular sandwich plates with various geometric patterns of lattice core have been analytically examined in this work.The plate comprises a lattic...For the first time,the linear and nonlinear vibrations of composite rectangular sandwich plates with various geometric patterns of lattice core have been analytically examined in this work.The plate comprises a lattice core located in the middle and several homogeneous orthotropic layers that are symmetrical relative to it.For this purpose,the partial differential equations of motion have been derived based on the first-order shear deformation theory,employing Hamilton’s principle and Von Kármán’s nonlinear displacement-strain relations.Then,the nonlinear partial differential equations of the plate are converted into a time-dependent nonlinear ordinary differential equation(Duffing equation)by applying the Galerkin method.From the solution of this equation,the natural frequencies are extracted.Then,to calculate the non-linear frequencies of the plate,the non-linear equation of the plate has been solved analytically using the method of multiple scales.Finally,the effect of some critical parameters of the system,such as the thickness,height,and different angles of the stiffeners on the linear and nonlinear frequencies,has been analyzed in detail.To confirmthe solution method,the results of this research have been compared with the reported results in the literature and finite elements in ABAQUS,and a perfect match is observed.The results reveal that the geometry and configuration of core ribs strongly affect the natural frequencies of the plate.展开更多
Lung cancer continues to be a leading cause of cancer-related deaths worldwide,emphasizing the critical need for improved diagnostic techniques.Early detection of lung tumors significantly increases the chances of suc...Lung cancer continues to be a leading cause of cancer-related deaths worldwide,emphasizing the critical need for improved diagnostic techniques.Early detection of lung tumors significantly increases the chances of successful treatment and survival.However,current diagnostic methods often fail to detect tumors at an early stage or to accurately pinpoint their location within the lung tissue.Single-model deep learning technologies for lung cancer detection,while beneficial,cannot capture the full range of features present in medical imaging data,leading to incomplete or inaccurate detection.Furthermore,it may not be robust enough to handle the wide variability in medical images due to different imaging conditions,patient anatomy,and tumor characteristics.To overcome these disadvantages,dual-model or multi-model approaches can be employed.This research focuses on enhancing the detection of lung cancer by utilizing a combination of two learning models:a Convolutional Neural Network(CNN)for categorization and the You Only Look Once(YOLOv8)architecture for real-time identification and pinpointing of tumors.CNNs automatically learn to extract hierarchical features from raw image data,capturing patterns such as edges,textures,and complex structures that are crucial for identifying lung cancer.YOLOv8 incorporates multiscale feature extraction,enabling the detection of tumors of varying sizes and scales within a single image.This is particularly beneficial for identifying small or irregularly shaped tumors that may be challenging to detect.Furthermore,through the utilization of cutting-edge data augmentation methods,such as Deep Convolutional Generative Adversarial Networks(DCGAN),the suggested approach can handle the issue of limited data and boost the models’ability to learn from diverse and comprehensive datasets.The combined method not only improved accuracy and localization but also ensured efficient real-time processing,which is crucial for practical clinical applications.The CNN achieved an accuracy of 97.67%in classifying lung tissues into healthy and cancerous categories.The YOLOv8 model achieved an Intersection over Union(IoU)score of 0.85 for tumor localization,reflecting high precision in detecting and marking tumor boundaries within the images.Finally,the incorporation of synthetic images generated by DCGAN led to a 10%improvement in both the CNN classification accuracy and YOLOv8 detection performance.展开更多
Manganese-based chalcogenides have significant potential as anodes for sodium-ion batteries(SIBs) due to their high theoretical specific capacity, abundant natural reserves, and environmental friendliness. However, th...Manganese-based chalcogenides have significant potential as anodes for sodium-ion batteries(SIBs) due to their high theoretical specific capacity, abundant natural reserves, and environmental friendliness. However, their application is hindered by poor cycling stability, resulting from severe volume changes during cycling and slow reaction kinetics due to their complex crystal structure. Here, an efficient and straightforward strategy was employed to in-situ encapsulate single-phase porous nanocubic MnS_(0.5)Se_(0.5) into carbon nanofibers using electrospinning and the hard template method, thus forming a necklace-like porous MnS_(0.5)Se_(0.5)-carbon nanofiber composite(MnS_(0.5)Se_(0.5)@N-CNF). The introduction of Se significantly impacts both the composition and microstructure of MnS_(0.5)Se_(0.5), including lattice distortion that generates additional defects, optimization of chemical bonds, and a nano-spatially confined design. In situ/ex-situ characterization and density functional theory calculations verified that this MnS_(0.5)Se_(0.5)@N-CNF allevi- ates the volume expansion and facilitates the transfer of Na+/electron. As expected, MnS_(0.5)Se_(0.5)@N-CNF anode demonstrates excellent sodium storage performance, characterized by high initial Coulombic efficiency(90.8%), high-rate capability(370.5 m Ahg^(-1) at 10 Ag^(-1)) and long durability(over 5000 cycles at 5 Ag^(-1)). The MnS_(0.5)Se_(0.5)@N-CNF//NVP@C full cell, assembled with MnS_(0.5)Se_(0.5)@N-CNF as anode and Na_(3)V_(2)(PO_4)_(3)@C as cathode, exhibits a high energy density of 254 Wh kg^(-1) can be provided. This work presents a novel strategy to optimize the design of anode materials through structural engineering and Se substitution, while also elucidating the underlying reaction mechanisms.展开更多
The sedimentary geochemistry of St.Martin’s Island is important to determine the origin of the source rock,paleo weathering,tectonic setting,sediment recycling,maturity,sorting,redox condition,and paleo salinity of t...The sedimentary geochemistry of St.Martin’s Island is important to determine the origin of the source rock,paleo weathering,tectonic setting,sediment recycling,maturity,sorting,redox condition,and paleo salinity of the sediments.Major oxides,trace elements,and rare earth elements(REEs)obtained from the INAA technique are presented by analyzing the sediment samples collected from the shoreline of St.Martin’s Island,Bangladesh.The elemental ratios,comparison with average upper continental crust(UCC),binary diagrams(Th/Sc vs.Sc,La/Th vs.Hf,Th/Co vs.La/Sc),and chondrite normalized REE patterns exhibit substantial LREE enrichment,relatively fl at HREE fractionation,considerable negative Eu anomalies(average:0.72),indicates the derivation from a source dominated by felsic rock,with contribution from intermediate source and mafi c component.Sediments from St.Martin’s Island exhibit the deposition of sediments in transitional environments of active and passive continental margin settings.Weathering indices value of CIA,PIA,CIW,CIX,and K 2 O/Rb ratio show moderate chemical weathering,indicating that the sediments are chemically mature.Sedimentary redox indicative proxies,such as U/Th,V/Cr,and V/Sc,show an oxic depositional environment during sediment deposition.The intermediate CIA and other weathering index values of the St.Martin’s sediments show that the area had semiarid and humid climatic conditions throughout the deposition.The Rb/K ratio of the St.Martin’s sediments suggests that the development and deposition of the sedimentary sequence of St.Martin’s Island mainly occurred in a brackish water environment during the geological past.展开更多
In the article“Deep Learning-Enhanced Brain Tumor Prediction via Entropy-Coded BPSO in CIELAB Color Space”by Mudassir Khalil,Muhammad Imran Sharif,Ahmed Naeem,Muhammad Umar Chaudhry,Hafiz Tayyab Rauf,Adham E.Ragab C...In the article“Deep Learning-Enhanced Brain Tumor Prediction via Entropy-Coded BPSO in CIELAB Color Space”by Mudassir Khalil,Muhammad Imran Sharif,Ahmed Naeem,Muhammad Umar Chaudhry,Hafiz Tayyab Rauf,Adham E.Ragab Computers,Materials&Continua,2023,Vol.77,No.2,pp.2031–2047.DOI:10.32604/cmc.2023.043687,URL:https://www.techscience.com/cmc/v77n2/54831,there was an error regarding the affiliation for the author Hafiz Tayyab Rauf.Instead of“Centre for Smart Systems,AI and Cybersecurity,Staffordshire University,Stoke-on-Trent,ST42DE,UK”,the affiliation should be“Independent Researcher,Bradford,BD80HS,UK”.展开更多
Extreme weather events,such as floods and droughts,are expected to rise significantly worldwide as a result of climate change.Investigating future drought patterns is therefore a key approach for elaborating anticipat...Extreme weather events,such as floods and droughts,are expected to rise significantly worldwide as a result of climate change.Investigating future drought patterns is therefore a key approach for elaborating anticipatory water resources management responses to climate change.In this paper,future meteorological drought conditions are investigated based on the SPEI(Standardised Precipitation Evapotranspiration Index).This study makes use of observed and projected data.The simulated data were retrieved from the CMIP6(Coupled Model Intercomparison Project Phase 6)over the period 2025-2050,and the Delta change method was adopted to remove the bias in the dataset.Then SPEI at various scales has been estimated under four future scenarios(SSP1-2.6,SSP2-4.5,SSP3-7.0 and SSP5-8.5).The trend analysis of the projected SPEI was performed at p<0.05 using the MMK(Modified Mann-Kendall)test in order to detect the statistically significant trend of the drought against the null hypothesis of no trend.Results show large variability in the magnitude of drought in the past and future.Based on SPEI at 24 months accumulation,the result shows that under SSP1-2.6,the basin will experience a wet period during the first decade(SPEI=0.60),the second decade will be dry(SPEI24=-0.43).The remaining years will be also dry(SPEI=-0.34).Under SSP2-4.5,SSP3-7.0 and SSP5-8.5 scenarios,the district will experience a wet period during the first two decades with SPEI ranging from 0.38 to 0.59.This wet period will be followed by a dry period under these scenarios ranging from-0.14 to-0.06.Overall,under SSPs scenarios,two main periods characterized by a rainfall recovery spanning from followed by a moderately prolonged drought are identified within the study area.The findings of this study may provide valuable information for developing proactive measures to reduce water insecurity in Fada N’Gourma through effective drought mitigation.展开更多
The paper primarily focuses on social safety nets and their effectiveness in poverty alleviation.Social Safety Net(SSN)programs pertain to social service initiatives aimed at providing temporary assistance to individu...The paper primarily focuses on social safety nets and their effectiveness in poverty alleviation.Social Safety Net(SSN)programs pertain to social service initiatives aimed at providing temporary assistance to individuals or groups facing vulnerabilities or unexpected hardships,such as those with lower incomes.Poverty poses a significant obstacle to the progress of social development,and its impacts are worsened by various factors including insecurity,frequent flooding,and droughts in Somalia.A total of 342 households in the Banadir region of Somalia were interviewed for the social safety nets(SSN)study.Data collection in the study was facilitated through the utilization of Kobo Toolbox,while the data analysis was conducted using EViews v.12.The results obtained from the ADP and PP tests indicated that all variables exhibited stationarity at the level.The Impact Assessment(IA)reveals a positive correlation with Household Income and Poverty Indices(HIPI),suggesting a risk of dependency without a strategic exit strategy,potentially leading to a 26%increase in poverty levels.A well-executed Program Implementation and Design(PID)can result in a 33%increase in income and poverty indices.Recipients perceive the Social Safety Net(PSSN)as reducing poverty and increasing income by 11%.Therefore,the study recommends integrating beneficiaries into the urban economy through sustainable livelihood options.Finally,the Somali government should prioritize the implementation of sustainable livelihood programs to mitigate dependency and alleviate poverty among SSN beneficiaries.展开更多
To the Editor:Liver transplantation is widely regarded as the definitive treat-ment for patients with end-stage liver disease.However,the per-sistent shortage of cadaveric liver grafts has driven the develop-ment of l...To the Editor:Liver transplantation is widely regarded as the definitive treat-ment for patients with end-stage liver disease.However,the per-sistent shortage of cadaveric liver grafts has driven the develop-ment of living-donor liver transplantation(LDLT).Despite its ben-efits,LDLT raises substantial concerns regarding donor morbid-ity,as the procedure involves operating on a healthy individual.Complications associated with donor hepatectomy include abdom-inal trauma,chronic wound pain,physical stress,and psycholog-ical burdens[1,2].In light of these challenges,minimally inva-sive approaches,including laparoscopic and robotic donor hepa-tectomy,have been introduced to mitigate risks and enhance re-covery[3].However,the impact of these techniques on male sex-ual function-a critical aspect of donor quality of life-remains underexplored.Several retrospective studies have highlighted sex-ual dysfunction and altered spousal relationships following open donor hepatectomy[4-6].For instance,9%of donors reported a de-crease in sexual activity,and a significant proportion experienced low body image perceptions.展开更多
Background:This retrospective cross-sectional study evaluated the antibiogram profile of Gram-negative bacterial infections at Yastebsheron Hospital.The study aimed to identify prevalent pathogens,assess antimicrobial...Background:This retrospective cross-sectional study evaluated the antibiogram profile of Gram-negative bacterial infections at Yastebsheron Hospital.The study aimed to identify prevalent pathogens,assess antimicrobial susceptibility patterns,and develop evidence-based recommendations for empirical antibiotic therapy.Methods:A total of 1,182 clinical specimens(urine,swabs,aspirates,and cerebrospinal fluid)collected in 2022 were analyzed following standard microbiological procedures.Culture and sensitivity testing were performed according to established protocols.Data were analyzed using SPSS version 23 and Microsoft Excel,with results presented through descriptive statistics.Results:Gram-negative bacteria accounted for 48.4%of isolates.Urinary tract infections(UTIs)were the most prevalent,with a significantly higher incidence among female patients(67%).Escherichia coli(59.8%)was the predominant uropathogen.Among the frequently isolated pathogens E.coli(52.5%),Enterobacter spp.(21.9%),Proteus mirabilis(9.8%),and Pseudomonas aeruginosa(8.4%)meropenem demonstrated the highest efficacy.Levofloxacin showed excellent activity against Enterobacter spp.and P.mirabilis(92%susceptibility),while amikacin exhibited moderate effectiveness against E.coli(78%).Morganella morganii displayed the highest multidrug-resistance rates.Colistin was universally effective against P.aeruginosa.Third-generation cephalosporins and nalidixic acid showed limited efficacy against E.coli(21-41%susceptibility).P.mirabilis,Klebsiella pneumoniae,and M.morganii demonstrated low susceptibility to most tested antibiotics.Conclusion:Regular antibiogram updates are essential for monitoring antimicrobial resistance trends and guiding empirical therapy.The study findings support the use of meropenem and levofloxacin as first-line options while highlighting concerning resistance patterns to cephalosporins and quinolones.Local susceptibility data remain crucial for optimizing antibiotic selection and stewardship efforts.展开更多
Centella asiatica L.,a medicinal herb,has attracted substantial interest in research as well as commercial domains due to its bioactive compounds which include the pentacyclic triterpenoid centellosides,and in additio...Centella asiatica L.,a medicinal herb,has attracted substantial interest in research as well as commercial domains due to its bioactive compounds which include the pentacyclic triterpenoid centellosides,and in addition,hydroxy.In addition,hydroxycinnamic acid conjugates as well as flavonoids.The latter is the major class of secondary plant metabolites and comprises various subclasses,including anthocyanidins.Anthocyanins are rarely reported in extracts from C.asiatica and differ structurally due to a flavylium(2-phenylchromenylium)ion that carries a positive charge at the oxygen atom of the C-ring of the basic flavonoid structure.Callus of C.asiatica was initiated and propagated on synthetic media and subjected to different light regimes.White callus resulted from white fluorescent illumination,while purple callus developed in response to white light emitting diode(LED)illumination.To profile the metabolites responsible for the intense purple coloration,methanolic extracts were prepared from the two cell lines.Total phenolic,flavonoid,and anthocyanin content were determined and indicated(i)very low levels of flavonoids and anthocyanins in white callus and(ii)that anthocyanins dominate the flavonoid content of the purple callus.Extracts were subjected to untargeted ultra-high-performance liquid chromatography coupled to high-definition mass spectrometry(UHPLC–MS)to profile newly synthesized anthocyanins.Metabolite annotation was based on accurate mass determination and characteristic fragmentation patterns.Here,the reprogramming of the metabolome of white C.asiatica callus due to LED illumination is reported and the profiles of cryptic anthocyanins as well as putative flavonoid and caffeoylquinic acid co-pigments in purple callus are described.展开更多
We used fast chlorophyll fluorescence transients(OJIP) to study provenance-related differences in photosynthetic performance and the magnitude of day-to-day chlorophyll fluorescence(ChlF) variation in northern(67°...We used fast chlorophyll fluorescence transients(OJIP) to study provenance-related differences in photosynthetic performance and the magnitude of day-to-day chlorophyll fluorescence(ChlF) variation in northern(67°N)and southern(62°N) silver birches in a common garden at62°N.ChlF transients were measured five times during two weeks in the middle of summer to avoid seasonal variation.Differences in growth and leaf morphological traits between the provenances were also examined.The northern trees had higher chlorophyll content,larger leaf areas,and higher leaf fresh and dry mass than the southern trees,but the leaf mass per area did not differ between the provenances.The southern trees were taller and showed higher annual shoot growth than the northern trees.For all the ChlF parameters,day-to-day variation was significant and followed the same pattern for both provenances with no significant provenance ×day interaction,suggesting a similar response to environmental variation.The northern provenance had higher values in parameters related to the reduction of end electron acceptors at the Photosystem I(PSI) acceptor side as probed by ChlF.This and higher values for performance indices PI_(abs) and PI_(tot) in northern than in southern trees suggest higher photosynthetic performance of northern trees in line with the latitudinal compensation strategy.Provenance differences in these parameters increased towards the end of the measurement period,suggesting preparation for earlier growth cessation in northern trees triggered by the shortening day length.The study shows that provenance differences in ChlF can be relatively stable regardless of environmental variation but might be influenced by physiological alterations in preparation for future changes in environmental conditions.展开更多
The Caribbean presents a wide range of opportunities with varying potential to contribute to the Gross National Incomes of the countries.However,the tourism industry remains a key source of income but is vulnerable to...The Caribbean presents a wide range of opportunities with varying potential to contribute to the Gross National Incomes of the countries.However,the tourism industry remains a key source of income but is vulnerable to disasters and other upheavals.There are alternatives to sustainable growth such as the blue economy with the potential for hydrogen extraction from the Caribbean Sea,which can make a signi fiicant contribution.The Caribbean Transshipment Triangle boasts signi fiicant port infrastructure that plays a crucial role in transporting goods and has the potential to become hydrogen hubs.The aim of this research is to examine the potential for countries in the region to develop this industry.A quantitative methodology was employed to examine the correlation between renewable energy and economic growth among six major transshipment countries in the Caribbean transshipment triangle,from 2010 to 2020.The study employed the Pearson correlation coef fiicient to analyze the data collected from these countries.The fiindings indicated that the Dominican Republic and Panama had the highest correlation between renewable energy and economic growth.Speci fiically,Jamaica,Panama,and the Dominican Republic demonstrated a moderate to high correlation between Renewable Power Capacity(RPC)and GDP.Consequently,investing in port infrastructure to facilitate hydrogen production,storage,distribution,and export could have positive effects on these economies.These fiindings are of interest to governments,managers,professionals,policymakers,and investors in the power generation sector.The research supports visions of a resilient blue economy and addresses sustainable development concerns in the Caribbean region.展开更多
Phosphoric acid is a key ingredient in fertilizer production and contains many rare earth elements(REEs).Recovering REEs from phosphoric acid can prevent the accumulation of these elements in the soil and help bridge ...Phosphoric acid is a key ingredient in fertilizer production and contains many rare earth elements(REEs).Recovering REEs from phosphoric acid can prevent the accumulation of these elements in the soil and help bridge the gap between supply and demand.In this concern,a new material called Si-6G PAMAMPPAAM dendrimers modified silica gel terminated with phenylphosphonic acid-amide moieties was developed and its ability to adsorb Nd(Ⅲ)and Er(Ⅲ)from the phosphoric acid solution was investigated.K inetics and isotherm of the uptake process were investigated to explo re the so rption characte ristics.The attained results show that both metal ions exhibit the same adsorption performance,and the uptake process is depicted as a chemisorption,monolayer,uniform,and homogeneous process.The equilibrium state is achieved within 120 min,and the maximum uptake capacity is 16.7 mg Nd(Ⅲ)/g,and 14.0 mg Er(Ⅲ)/g.Sorption thermodynamics is an endothermic,spontaneous,and feasible uptake process.Nitric acid(1.0 mol/L)is found to be efficient for adsorbing about 94.3%and 92.5%of neodymium(Ⅲ)and erbium(Ⅲ)respectively,and the prepared Si-6G PAMAM-PPAAM demonstrates excellent stability over five consecutive sorption/desorption cycles.Preliminary tests on commercial phosphoric acid demonstrate that Si-6G PAMAM-PPAAM retains its effective REEs uptake from a complex comm ercial phosph oric acid solution.展开更多
Alkaline igneous rocks represent one of the most economically important resources of radioactive minerals and rare metals.New field observations and petrographic studies are integrated with whole-rock geochemical anal...Alkaline igneous rocks represent one of the most economically important resources of radioactive minerals and rare metals.New field observations and petrographic studies are integrated with whole-rock geochemical analyses and Gamma ray spectroscopy data of alkaline rocks associated with the Amreit complex.The fieldwork was achieved by the collection of more than forty samples from alkaline granites and alkaline syenites.The youngest rocks cropping out in the study area are the cogenetic alkaline rocks,ranging from alkaline granite to alkaline syenite.These alkaline rocks are composed essentially of K-feldspar,alkali amphiboles(arfvedsonite),and sodic pyroxene,with accessories such as zircon,apatite,and ilmenite.Mineral characterization of the highly radioactive zones in both alkaline granite and alkaline syenite displays enrichment in monazite,thorite,zircon,ferro-columbite,xenotime,and allanite minerals.Geochemical analyses indicate that the Amreit rocks are alkaline with peralkaline affinity and have high concentrations of total alkalis(K_(2)O+Na_(2)O),large ion lithophile elements(LILEs;Ba and Rb),high field strength elements(HFSEs;Y,Zr and Nb),rare earth elements(REEs)and significantly depleted in K,Sr,P,Ti,and Eu,typically of post-collision A-type granites.Typically,the Amreit alkaline igneous rocks are classified as within plate granites and display A2 subtype characteristics.The fractionation of K-feldspars played a distinctive role during the magmatic evolution of these alkaline rocks.The geochemical characteristics indicate that the studied alkaline igneous rocks which were originated by fractional crystallization of alkaline magmas were responsible for the enrichment of the REE and rare metals in the residual melt.The high radioactivity is essentially related to accessory minerals,such as zircon,allanite,and monazite.The alkaline granite is the most U-and Thrich rock,where radioactivity level reaches up to 14.7 ppm(181.55 Bq/kg)e U,40.6 ppm(164.84 Bq/kg)e Th,whereas in alkaline syenite radioactivity level is 8.5 ppm(104.96 Bq/kg)e U,30.2 ppm(122.61 Bq/kg)e Th.These observations suppose that these alkaline rocks may be important targets for REEs and radioactive mineral exploration.展开更多
Sedimentation in reservoirs is a significant challenge that affects water storage capacity and operational efficiency.This study establishes a baseline sedimentation status for Mwimba Reservoir in Kasungu,Malawi,five ...Sedimentation in reservoirs is a significant challenge that affects water storage capacity and operational efficiency.This study establishes a baseline sedimentation status for Mwimba Reservoir in Kasungu,Malawi,five years after its commissioning in 2017,using an integrated bathymetric survey and Geographic Information System(GIS)analysis.A bathymetric survey conducted in March 2022 collected depth measurements at 507 points along 23 transects,which were used to construct a Triangulated Irregular Network(TIN)model in ArcGIS for accurate volume calculations.Sediment concentration was determined from seven water samples using the filtration method.The original design volume of 89,200 m^(3)was compared to the current volume of 72,966 m^(3),indicating an 18.2% loss in capacity over the five-year period.Statistical analysis using a one-sample T-test confirmed that this reduction is significant(p=0.013).The annual sedimentation rate was estimated at 1.25 tonnes per year,and the reservoir’s projected operational life is 27.5 years if no intervention is undertaken.Despite a relatively low sedimentation rate compared to other regional reservoirs,targeted sediment management and further catchment analysis are essential.This study provides critical baseline data for future sediment monitoring,management,and conservation planning for Mwimba Reservoir and similar small water bodies in Sub-Saharan Africa.展开更多
Only a few studies have reported the efects of electrochemical hydrogenation on the tensile mechanical properties of additively manufactured Ti–6Al–4V alloy,in all of them the alloy was processed by laser powder-bed...Only a few studies have reported the efects of electrochemical hydrogenation on the tensile mechanical properties of additively manufactured Ti–6Al–4V alloy,in all of them the alloy was processed by laser powder-bed fusion.Furthermore,the efects of either hot isostatic pressing(HIP)or heat treatment(HT)post-treatments on the mechanical properties were not reported.Here,the Young’s modulus,ultimate tensile stress,and uniform(homogeneous)strain of as-built electron beam melted(EBM)Ti–6Al–4V alloys were studied using small tensile specimens before and after electrochemical hydrogenation,as well as before and after secondary processes of HIP at 920℃ and HT at 1000℃.The tensile properties of all hydrogenated alloys were signifcantly degraded compared to their non-hydrogenated counterparts.The yield stress could not be determined for all hydrogenated alloys,as failure occurred at a strain below 0.2%ofset.The uniform strain of the hydrogenated alloys was less than 1%,compared to 1%–5%for the non-hydrogenated alloys.The fracture mode of the hydrogenated alloys after HIP and HT revealed cleavage fracture,indicating increased brittleness.In the as-built hydrogenated alloy,the fracture mode varied with location:brittle fracture occurred near the surface due to the formation of a hydride layer,while a more ductile fracture with dimples was observed below this layer.展开更多
In many developing countries with poorly managed landscapes,soil erosion threatens the sustainability of water bodies.The main limitations of this study are the lack of daily sediment data,lithology,higher-resolution ...In many developing countries with poorly managed landscapes,soil erosion threatens the sustainability of water bodies.The main limitations of this study are the lack of daily sediment data,lithology,higher-resolution DEM data,and socioeconomic factors.Poor land use policy and resource management in the Upper Awash Sub-basin lead to soil erosion and sedimentation of hydrological infrastructure,Effective watershed prioritization requires integrating land use,hydrology,sediment load,and morphometric factors but often faces gaps,especially in the study area.This research aims to prioritise the Upper Awash Sub-Basin by its morphometric,land use and cover(LULC),and sediment yield characteristics.We used the integrated AHP-VIKOR multi-attribute decision-making method to prioritise watersheds,incorporating morphometry,LULC,and sediment load attributes in the simple matrix approach.The findings showed the following classes of erosion:exceedingly high(2722.14 km2),high(2524.46 km2),moderate(2205.48 km2),low(1611.43 km2),and extremely low(854.35 km2).Sub-watersheds WS6,WS8,WS10,WS13,and WS24 are the top priority for watershed management.The study ranked watersheds based on various attributes but encountered limitations such as the lack of daily sediment data,geological structure,and lithology.It can be concluded that this approach is very important to identify and categorize hotspots of soil erosion sub-watersheds for planners and decision-makers for conserving water and soil and for different environmental management purposes.展开更多
基金supported by the National Research Foundation of Korea(NRF)grant funded by the Korean government(MSIT)(No.RS-2022–00165798)Anhui Natural Science Foundation(No.2308085MF211)The authors extend their appreciation to the Deanship of Research and Graduate Studies at King Khalid University for funding this work through Large Research Project under Grant Number(R.G.P.2/491/45).
文摘The rapid advancement of nanotechnology has sparked much interest in applying nanoscale perovskite materials for photodetection applications.These materials are promising candidates for next-generation photodetectors(PDs)due to their unique optoelectronic properties and flexible synthesis routes.This review explores the approaches used in the development and use of optoelectronic devices made of different nanoscale perovskite architectures,including quantum dots,nanosheets,nanorods,nanowires,and nanocrystals.Through a thorough analysis of recent literature,the review also addresses common issues like the mechanisms underlying the degradation of perovskite PDs and offers perspectives on potential solutions to improve stability and scalability that impede widespread implementation.In addition,it highlights that photodetection encompasses the detection of light fields in dimensions other than light intensity and suggests potential avenues for future research to overcome these obstacles and fully realize the potential of nanoscale perovskite materials in state-of-the-art photodetection systems.This review provides a comprehensive overview of nanoscale perovskite PDs and guides future research efforts towards improved performance and wider applicability,making it a valuable resource for researchers.
文摘Friction stir welding(FSW)is a relatively new welding technique that has significant advantages compared to the fusion welding techniques in joining non weld able alloys by fusion,such as aluminum alloys.Three FSW seams of AA6061-T6 plates were made us-ing different FSW parameters.The structure of the FSW seams was investigated using X-ray diffraction(XRD),scanning electron mi-croscope(SEM)and non destructive testing(NDT)techniques and their hardness was also measured.The dominated phase in the AA6061-T6 alloy and the FSW seams was theα-Al.The FSW seam had lower content of the secondary phases than the AA6061-T6 al-loy.The hardness of the FSW seams was decreased by about 30%compared to the AA6061-T6 alloy.The temperature distributions in the weld seams were also studied experimentally and numerically modeled and the results were in a good agreement.
基金supported by the National Natural Science Foundation of China(No.32071980)the Key Projects of Shaanxi Agricultural Collaborative Innovation and Extension Alliance(No.LMZD202201)+1 种基金the Key R&D Project in Shaanxi Province(No.2021LLRH-07)Shaanxi Natural Scientific Basic Research Program project(No.2022JQ-157).
文摘Agricultural practices significantly contribute to greenhouse gas(GHG)emissions,necessitating cleaner production technologies to reduce environmental pressure and achieve sustainable maize production.Plastic film mulching is commonly used in the Loess Plateau region.Incorporating slow-release fertilizers as a replacement for urea within this practice can reduce nitrogen losses and enhance crop productivity.Combining these techniques represents a novel agricultural approach in semi-arid areas.However,the impact of this integration on soil carbon storage(SOCS),carbon footprint(CF),and economic benefits has received limited research attention.Therefore,we conducted an eight-year study(2015-2022)in the semi-arid northwestern region to quantify the effects of four treatments[urea supplied without plastic film mulching(CK-U),slow-release fertilizer supplied without plastic film mulching(CK-S),urea supplied with plastic film mulching(PM-U),and slow-release fertilizer supplied with plastic film mulching(PM-S)]on soil fertility,economic and environmental benefits.The results revealed that nitrogen fertilizer was the primary contributor to total GHG emissions(≥71.97%).Compared to other treatments,PM-S increased average grain yield by 12.01%-37.89%,water use efficiency by 9.19%-23.33%,nitrogen accumulation by 27.07%-66.19%,and net return by 6.21%-29.57%.Furthermore,PM-S decreased CF by 12.87%-44.31%and CF per net return by 14.25%-41.16%.After eight years,PM-S increased SOCS(0-40 cm)by 2.46%,while PM-U decreased it by 7.09%.These findings highlight the positive effects of PM-S on surface soil fertility,economic gains,and environmental benefits in spring maize production on the Loess Plateau,underscoring its potential for widespread adoption and application.
文摘For the first time,the linear and nonlinear vibrations of composite rectangular sandwich plates with various geometric patterns of lattice core have been analytically examined in this work.The plate comprises a lattice core located in the middle and several homogeneous orthotropic layers that are symmetrical relative to it.For this purpose,the partial differential equations of motion have been derived based on the first-order shear deformation theory,employing Hamilton’s principle and Von Kármán’s nonlinear displacement-strain relations.Then,the nonlinear partial differential equations of the plate are converted into a time-dependent nonlinear ordinary differential equation(Duffing equation)by applying the Galerkin method.From the solution of this equation,the natural frequencies are extracted.Then,to calculate the non-linear frequencies of the plate,the non-linear equation of the plate has been solved analytically using the method of multiple scales.Finally,the effect of some critical parameters of the system,such as the thickness,height,and different angles of the stiffeners on the linear and nonlinear frequencies,has been analyzed in detail.To confirmthe solution method,the results of this research have been compared with the reported results in the literature and finite elements in ABAQUS,and a perfect match is observed.The results reveal that the geometry and configuration of core ribs strongly affect the natural frequencies of the plate.
文摘Lung cancer continues to be a leading cause of cancer-related deaths worldwide,emphasizing the critical need for improved diagnostic techniques.Early detection of lung tumors significantly increases the chances of successful treatment and survival.However,current diagnostic methods often fail to detect tumors at an early stage or to accurately pinpoint their location within the lung tissue.Single-model deep learning technologies for lung cancer detection,while beneficial,cannot capture the full range of features present in medical imaging data,leading to incomplete or inaccurate detection.Furthermore,it may not be robust enough to handle the wide variability in medical images due to different imaging conditions,patient anatomy,and tumor characteristics.To overcome these disadvantages,dual-model or multi-model approaches can be employed.This research focuses on enhancing the detection of lung cancer by utilizing a combination of two learning models:a Convolutional Neural Network(CNN)for categorization and the You Only Look Once(YOLOv8)architecture for real-time identification and pinpointing of tumors.CNNs automatically learn to extract hierarchical features from raw image data,capturing patterns such as edges,textures,and complex structures that are crucial for identifying lung cancer.YOLOv8 incorporates multiscale feature extraction,enabling the detection of tumors of varying sizes and scales within a single image.This is particularly beneficial for identifying small or irregularly shaped tumors that may be challenging to detect.Furthermore,through the utilization of cutting-edge data augmentation methods,such as Deep Convolutional Generative Adversarial Networks(DCGAN),the suggested approach can handle the issue of limited data and boost the models’ability to learn from diverse and comprehensive datasets.The combined method not only improved accuracy and localization but also ensured efficient real-time processing,which is crucial for practical clinical applications.The CNN achieved an accuracy of 97.67%in classifying lung tissues into healthy and cancerous categories.The YOLOv8 model achieved an Intersection over Union(IoU)score of 0.85 for tumor localization,reflecting high precision in detecting and marking tumor boundaries within the images.Finally,the incorporation of synthetic images generated by DCGAN led to a 10%improvement in both the CNN classification accuracy and YOLOv8 detection performance.
基金financially supported by the National Natural Science Foundation of China (No. 22225902, U22A20436, 22209185)National Key Research&Development Program of China (2022YFE0115900, 2023YFA1507101, 2021YFA1501500)+1 种基金the Self-deployment Project Research Program of Haixi Institutes,Chinese Academy of Sciences (No. CXZX-2022-GH04, CXZX-2023-JQ08)Science and Technology Program of Fuzhou (2023-P-009)。
文摘Manganese-based chalcogenides have significant potential as anodes for sodium-ion batteries(SIBs) due to their high theoretical specific capacity, abundant natural reserves, and environmental friendliness. However, their application is hindered by poor cycling stability, resulting from severe volume changes during cycling and slow reaction kinetics due to their complex crystal structure. Here, an efficient and straightforward strategy was employed to in-situ encapsulate single-phase porous nanocubic MnS_(0.5)Se_(0.5) into carbon nanofibers using electrospinning and the hard template method, thus forming a necklace-like porous MnS_(0.5)Se_(0.5)-carbon nanofiber composite(MnS_(0.5)Se_(0.5)@N-CNF). The introduction of Se significantly impacts both the composition and microstructure of MnS_(0.5)Se_(0.5), including lattice distortion that generates additional defects, optimization of chemical bonds, and a nano-spatially confined design. In situ/ex-situ characterization and density functional theory calculations verified that this MnS_(0.5)Se_(0.5)@N-CNF allevi- ates the volume expansion and facilitates the transfer of Na+/electron. As expected, MnS_(0.5)Se_(0.5)@N-CNF anode demonstrates excellent sodium storage performance, characterized by high initial Coulombic efficiency(90.8%), high-rate capability(370.5 m Ahg^(-1) at 10 Ag^(-1)) and long durability(over 5000 cycles at 5 Ag^(-1)). The MnS_(0.5)Se_(0.5)@N-CNF//NVP@C full cell, assembled with MnS_(0.5)Se_(0.5)@N-CNF as anode and Na_(3)V_(2)(PO_4)_(3)@C as cathode, exhibits a high energy density of 254 Wh kg^(-1) can be provided. This work presents a novel strategy to optimize the design of anode materials through structural engineering and Se substitution, while also elucidating the underlying reaction mechanisms.
基金Supporting Program for funding this work under Project number(RSP2024R328),King Saud University,Riyadh,Saudi Arabia.
文摘The sedimentary geochemistry of St.Martin’s Island is important to determine the origin of the source rock,paleo weathering,tectonic setting,sediment recycling,maturity,sorting,redox condition,and paleo salinity of the sediments.Major oxides,trace elements,and rare earth elements(REEs)obtained from the INAA technique are presented by analyzing the sediment samples collected from the shoreline of St.Martin’s Island,Bangladesh.The elemental ratios,comparison with average upper continental crust(UCC),binary diagrams(Th/Sc vs.Sc,La/Th vs.Hf,Th/Co vs.La/Sc),and chondrite normalized REE patterns exhibit substantial LREE enrichment,relatively fl at HREE fractionation,considerable negative Eu anomalies(average:0.72),indicates the derivation from a source dominated by felsic rock,with contribution from intermediate source and mafi c component.Sediments from St.Martin’s Island exhibit the deposition of sediments in transitional environments of active and passive continental margin settings.Weathering indices value of CIA,PIA,CIW,CIX,and K 2 O/Rb ratio show moderate chemical weathering,indicating that the sediments are chemically mature.Sedimentary redox indicative proxies,such as U/Th,V/Cr,and V/Sc,show an oxic depositional environment during sediment deposition.The intermediate CIA and other weathering index values of the St.Martin’s sediments show that the area had semiarid and humid climatic conditions throughout the deposition.The Rb/K ratio of the St.Martin’s sediments suggests that the development and deposition of the sedimentary sequence of St.Martin’s Island mainly occurred in a brackish water environment during the geological past.
文摘In the article“Deep Learning-Enhanced Brain Tumor Prediction via Entropy-Coded BPSO in CIELAB Color Space”by Mudassir Khalil,Muhammad Imran Sharif,Ahmed Naeem,Muhammad Umar Chaudhry,Hafiz Tayyab Rauf,Adham E.Ragab Computers,Materials&Continua,2023,Vol.77,No.2,pp.2031–2047.DOI:10.32604/cmc.2023.043687,URL:https://www.techscience.com/cmc/v77n2/54831,there was an error regarding the affiliation for the author Hafiz Tayyab Rauf.Instead of“Centre for Smart Systems,AI and Cybersecurity,Staffordshire University,Stoke-on-Trent,ST42DE,UK”,the affiliation should be“Independent Researcher,Bradford,BD80HS,UK”.
文摘Extreme weather events,such as floods and droughts,are expected to rise significantly worldwide as a result of climate change.Investigating future drought patterns is therefore a key approach for elaborating anticipatory water resources management responses to climate change.In this paper,future meteorological drought conditions are investigated based on the SPEI(Standardised Precipitation Evapotranspiration Index).This study makes use of observed and projected data.The simulated data were retrieved from the CMIP6(Coupled Model Intercomparison Project Phase 6)over the period 2025-2050,and the Delta change method was adopted to remove the bias in the dataset.Then SPEI at various scales has been estimated under four future scenarios(SSP1-2.6,SSP2-4.5,SSP3-7.0 and SSP5-8.5).The trend analysis of the projected SPEI was performed at p<0.05 using the MMK(Modified Mann-Kendall)test in order to detect the statistically significant trend of the drought against the null hypothesis of no trend.Results show large variability in the magnitude of drought in the past and future.Based on SPEI at 24 months accumulation,the result shows that under SSP1-2.6,the basin will experience a wet period during the first decade(SPEI=0.60),the second decade will be dry(SPEI24=-0.43).The remaining years will be also dry(SPEI=-0.34).Under SSP2-4.5,SSP3-7.0 and SSP5-8.5 scenarios,the district will experience a wet period during the first two decades with SPEI ranging from 0.38 to 0.59.This wet period will be followed by a dry period under these scenarios ranging from-0.14 to-0.06.Overall,under SSPs scenarios,two main periods characterized by a rainfall recovery spanning from followed by a moderately prolonged drought are identified within the study area.The findings of this study may provide valuable information for developing proactive measures to reduce water insecurity in Fada N’Gourma through effective drought mitigation.
文摘The paper primarily focuses on social safety nets and their effectiveness in poverty alleviation.Social Safety Net(SSN)programs pertain to social service initiatives aimed at providing temporary assistance to individuals or groups facing vulnerabilities or unexpected hardships,such as those with lower incomes.Poverty poses a significant obstacle to the progress of social development,and its impacts are worsened by various factors including insecurity,frequent flooding,and droughts in Somalia.A total of 342 households in the Banadir region of Somalia were interviewed for the social safety nets(SSN)study.Data collection in the study was facilitated through the utilization of Kobo Toolbox,while the data analysis was conducted using EViews v.12.The results obtained from the ADP and PP tests indicated that all variables exhibited stationarity at the level.The Impact Assessment(IA)reveals a positive correlation with Household Income and Poverty Indices(HIPI),suggesting a risk of dependency without a strategic exit strategy,potentially leading to a 26%increase in poverty levels.A well-executed Program Implementation and Design(PID)can result in a 33%increase in income and poverty indices.Recipients perceive the Social Safety Net(PSSN)as reducing poverty and increasing income by 11%.Therefore,the study recommends integrating beneficiaries into the urban economy through sustainable livelihood options.Finally,the Somali government should prioritize the implementation of sustainable livelihood programs to mitigate dependency and alleviate poverty among SSN beneficiaries.
文摘To the Editor:Liver transplantation is widely regarded as the definitive treat-ment for patients with end-stage liver disease.However,the per-sistent shortage of cadaveric liver grafts has driven the develop-ment of living-donor liver transplantation(LDLT).Despite its ben-efits,LDLT raises substantial concerns regarding donor morbid-ity,as the procedure involves operating on a healthy individual.Complications associated with donor hepatectomy include abdom-inal trauma,chronic wound pain,physical stress,and psycholog-ical burdens[1,2].In light of these challenges,minimally inva-sive approaches,including laparoscopic and robotic donor hepa-tectomy,have been introduced to mitigate risks and enhance re-covery[3].However,the impact of these techniques on male sex-ual function-a critical aspect of donor quality of life-remains underexplored.Several retrospective studies have highlighted sex-ual dysfunction and altered spousal relationships following open donor hepatectomy[4-6].For instance,9%of donors reported a de-crease in sexual activity,and a significant proportion experienced low body image perceptions.
文摘Background:This retrospective cross-sectional study evaluated the antibiogram profile of Gram-negative bacterial infections at Yastebsheron Hospital.The study aimed to identify prevalent pathogens,assess antimicrobial susceptibility patterns,and develop evidence-based recommendations for empirical antibiotic therapy.Methods:A total of 1,182 clinical specimens(urine,swabs,aspirates,and cerebrospinal fluid)collected in 2022 were analyzed following standard microbiological procedures.Culture and sensitivity testing were performed according to established protocols.Data were analyzed using SPSS version 23 and Microsoft Excel,with results presented through descriptive statistics.Results:Gram-negative bacteria accounted for 48.4%of isolates.Urinary tract infections(UTIs)were the most prevalent,with a significantly higher incidence among female patients(67%).Escherichia coli(59.8%)was the predominant uropathogen.Among the frequently isolated pathogens E.coli(52.5%),Enterobacter spp.(21.9%),Proteus mirabilis(9.8%),and Pseudomonas aeruginosa(8.4%)meropenem demonstrated the highest efficacy.Levofloxacin showed excellent activity against Enterobacter spp.and P.mirabilis(92%susceptibility),while amikacin exhibited moderate effectiveness against E.coli(78%).Morganella morganii displayed the highest multidrug-resistance rates.Colistin was universally effective against P.aeruginosa.Third-generation cephalosporins and nalidixic acid showed limited efficacy against E.coli(21-41%susceptibility).P.mirabilis,Klebsiella pneumoniae,and M.morganii demonstrated low susceptibility to most tested antibiotics.Conclusion:Regular antibiogram updates are essential for monitoring antimicrobial resistance trends and guiding empirical therapy.The study findings support the use of meropenem and levofloxacin as first-line options while highlighting concerning resistance patterns to cephalosporins and quinolones.Local susceptibility data remain crucial for optimizing antibiotic selection and stewardship efforts.
文摘Centella asiatica L.,a medicinal herb,has attracted substantial interest in research as well as commercial domains due to its bioactive compounds which include the pentacyclic triterpenoid centellosides,and in addition,hydroxy.In addition,hydroxycinnamic acid conjugates as well as flavonoids.The latter is the major class of secondary plant metabolites and comprises various subclasses,including anthocyanidins.Anthocyanins are rarely reported in extracts from C.asiatica and differ structurally due to a flavylium(2-phenylchromenylium)ion that carries a positive charge at the oxygen atom of the C-ring of the basic flavonoid structure.Callus of C.asiatica was initiated and propagated on synthetic media and subjected to different light regimes.White callus resulted from white fluorescent illumination,while purple callus developed in response to white light emitting diode(LED)illumination.To profile the metabolites responsible for the intense purple coloration,methanolic extracts were prepared from the two cell lines.Total phenolic,flavonoid,and anthocyanin content were determined and indicated(i)very low levels of flavonoids and anthocyanins in white callus and(ii)that anthocyanins dominate the flavonoid content of the purple callus.Extracts were subjected to untargeted ultra-high-performance liquid chromatography coupled to high-definition mass spectrometry(UHPLC–MS)to profile newly synthesized anthocyanins.Metabolite annotation was based on accurate mass determination and characteristic fragmentation patterns.Here,the reprogramming of the metabolome of white C.asiatica callus due to LED illumination is reported and the profiles of cryptic anthocyanins as well as putative flavonoid and caffeoylquinic acid co-pigments in purple callus are described.
基金supported by the University of Eastern FinlandCzech University of Life Sciences doctoral research funding to O.A+5 种基金North Karelia Regional Fund to O.A (grant number 55232028)University of Eastern Finland(strategic fundingproject 931060)the Academy of Finland(C-NEUT,project number 347862)part of the Academy of Finland Flagship on Photonics Research and Innovation (PREIN) decision (320166)the Finnish National Plant Phenotyping Infrastructure (NaPPI/Biocenter Finland)
文摘We used fast chlorophyll fluorescence transients(OJIP) to study provenance-related differences in photosynthetic performance and the magnitude of day-to-day chlorophyll fluorescence(ChlF) variation in northern(67°N)and southern(62°N) silver birches in a common garden at62°N.ChlF transients were measured five times during two weeks in the middle of summer to avoid seasonal variation.Differences in growth and leaf morphological traits between the provenances were also examined.The northern trees had higher chlorophyll content,larger leaf areas,and higher leaf fresh and dry mass than the southern trees,but the leaf mass per area did not differ between the provenances.The southern trees were taller and showed higher annual shoot growth than the northern trees.For all the ChlF parameters,day-to-day variation was significant and followed the same pattern for both provenances with no significant provenance ×day interaction,suggesting a similar response to environmental variation.The northern provenance had higher values in parameters related to the reduction of end electron acceptors at the Photosystem I(PSI) acceptor side as probed by ChlF.This and higher values for performance indices PI_(abs) and PI_(tot) in northern than in southern trees suggest higher photosynthetic performance of northern trees in line with the latitudinal compensation strategy.Provenance differences in these parameters increased towards the end of the measurement period,suggesting preparation for earlier growth cessation in northern trees triggered by the shortening day length.The study shows that provenance differences in ChlF can be relatively stable regardless of environmental variation but might be influenced by physiological alterations in preparation for future changes in environmental conditions.
文摘The Caribbean presents a wide range of opportunities with varying potential to contribute to the Gross National Incomes of the countries.However,the tourism industry remains a key source of income but is vulnerable to disasters and other upheavals.There are alternatives to sustainable growth such as the blue economy with the potential for hydrogen extraction from the Caribbean Sea,which can make a signi fiicant contribution.The Caribbean Transshipment Triangle boasts signi fiicant port infrastructure that plays a crucial role in transporting goods and has the potential to become hydrogen hubs.The aim of this research is to examine the potential for countries in the region to develop this industry.A quantitative methodology was employed to examine the correlation between renewable energy and economic growth among six major transshipment countries in the Caribbean transshipment triangle,from 2010 to 2020.The study employed the Pearson correlation coef fiicient to analyze the data collected from these countries.The fiindings indicated that the Dominican Republic and Panama had the highest correlation between renewable energy and economic growth.Speci fiically,Jamaica,Panama,and the Dominican Republic demonstrated a moderate to high correlation between Renewable Power Capacity(RPC)and GDP.Consequently,investing in port infrastructure to facilitate hydrogen production,storage,distribution,and export could have positive effects on these economies.These fiindings are of interest to governments,managers,professionals,policymakers,and investors in the power generation sector.The research supports visions of a resilient blue economy and addresses sustainable development concerns in the Caribbean region.
文摘Phosphoric acid is a key ingredient in fertilizer production and contains many rare earth elements(REEs).Recovering REEs from phosphoric acid can prevent the accumulation of these elements in the soil and help bridge the gap between supply and demand.In this concern,a new material called Si-6G PAMAMPPAAM dendrimers modified silica gel terminated with phenylphosphonic acid-amide moieties was developed and its ability to adsorb Nd(Ⅲ)and Er(Ⅲ)from the phosphoric acid solution was investigated.K inetics and isotherm of the uptake process were investigated to explo re the so rption characte ristics.The attained results show that both metal ions exhibit the same adsorption performance,and the uptake process is depicted as a chemisorption,monolayer,uniform,and homogeneous process.The equilibrium state is achieved within 120 min,and the maximum uptake capacity is 16.7 mg Nd(Ⅲ)/g,and 14.0 mg Er(Ⅲ)/g.Sorption thermodynamics is an endothermic,spontaneous,and feasible uptake process.Nitric acid(1.0 mol/L)is found to be efficient for adsorbing about 94.3%and 92.5%of neodymium(Ⅲ)and erbium(Ⅲ)respectively,and the prepared Si-6G PAMAM-PPAAM demonstrates excellent stability over five consecutive sorption/desorption cycles.Preliminary tests on commercial phosphoric acid demonstrate that Si-6G PAMAM-PPAAM retains its effective REEs uptake from a complex comm ercial phosph oric acid solution.
文摘Alkaline igneous rocks represent one of the most economically important resources of radioactive minerals and rare metals.New field observations and petrographic studies are integrated with whole-rock geochemical analyses and Gamma ray spectroscopy data of alkaline rocks associated with the Amreit complex.The fieldwork was achieved by the collection of more than forty samples from alkaline granites and alkaline syenites.The youngest rocks cropping out in the study area are the cogenetic alkaline rocks,ranging from alkaline granite to alkaline syenite.These alkaline rocks are composed essentially of K-feldspar,alkali amphiboles(arfvedsonite),and sodic pyroxene,with accessories such as zircon,apatite,and ilmenite.Mineral characterization of the highly radioactive zones in both alkaline granite and alkaline syenite displays enrichment in monazite,thorite,zircon,ferro-columbite,xenotime,and allanite minerals.Geochemical analyses indicate that the Amreit rocks are alkaline with peralkaline affinity and have high concentrations of total alkalis(K_(2)O+Na_(2)O),large ion lithophile elements(LILEs;Ba and Rb),high field strength elements(HFSEs;Y,Zr and Nb),rare earth elements(REEs)and significantly depleted in K,Sr,P,Ti,and Eu,typically of post-collision A-type granites.Typically,the Amreit alkaline igneous rocks are classified as within plate granites and display A2 subtype characteristics.The fractionation of K-feldspars played a distinctive role during the magmatic evolution of these alkaline rocks.The geochemical characteristics indicate that the studied alkaline igneous rocks which were originated by fractional crystallization of alkaline magmas were responsible for the enrichment of the REE and rare metals in the residual melt.The high radioactivity is essentially related to accessory minerals,such as zircon,allanite,and monazite.The alkaline granite is the most U-and Thrich rock,where radioactivity level reaches up to 14.7 ppm(181.55 Bq/kg)e U,40.6 ppm(164.84 Bq/kg)e Th,whereas in alkaline syenite radioactivity level is 8.5 ppm(104.96 Bq/kg)e U,30.2 ppm(122.61 Bq/kg)e Th.These observations suppose that these alkaline rocks may be important targets for REEs and radioactive mineral exploration.
基金the Agricultural Research and Extension Trust of Malawi and the Centre of Excellence of Transformative Agriculture Commercialisation at Lilongwe University of Agriculture and Natural Resources for supporting this study.
文摘Sedimentation in reservoirs is a significant challenge that affects water storage capacity and operational efficiency.This study establishes a baseline sedimentation status for Mwimba Reservoir in Kasungu,Malawi,five years after its commissioning in 2017,using an integrated bathymetric survey and Geographic Information System(GIS)analysis.A bathymetric survey conducted in March 2022 collected depth measurements at 507 points along 23 transects,which were used to construct a Triangulated Irregular Network(TIN)model in ArcGIS for accurate volume calculations.Sediment concentration was determined from seven water samples using the filtration method.The original design volume of 89,200 m^(3)was compared to the current volume of 72,966 m^(3),indicating an 18.2% loss in capacity over the five-year period.Statistical analysis using a one-sample T-test confirmed that this reduction is significant(p=0.013).The annual sedimentation rate was estimated at 1.25 tonnes per year,and the reservoir’s projected operational life is 27.5 years if no intervention is undertaken.Despite a relatively low sedimentation rate compared to other regional reservoirs,targeted sediment management and further catchment analysis are essential.This study provides critical baseline data for future sediment monitoring,management,and conservation planning for Mwimba Reservoir and similar small water bodies in Sub-Saharan Africa.
基金supported by the Pazy Foundation of the Israel Atomic Energy Commission and the Israeli Council of Higher Education(Grant No.322/20)。
文摘Only a few studies have reported the efects of electrochemical hydrogenation on the tensile mechanical properties of additively manufactured Ti–6Al–4V alloy,in all of them the alloy was processed by laser powder-bed fusion.Furthermore,the efects of either hot isostatic pressing(HIP)or heat treatment(HT)post-treatments on the mechanical properties were not reported.Here,the Young’s modulus,ultimate tensile stress,and uniform(homogeneous)strain of as-built electron beam melted(EBM)Ti–6Al–4V alloys were studied using small tensile specimens before and after electrochemical hydrogenation,as well as before and after secondary processes of HIP at 920℃ and HT at 1000℃.The tensile properties of all hydrogenated alloys were signifcantly degraded compared to their non-hydrogenated counterparts.The yield stress could not be determined for all hydrogenated alloys,as failure occurred at a strain below 0.2%ofset.The uniform strain of the hydrogenated alloys was less than 1%,compared to 1%–5%for the non-hydrogenated alloys.The fracture mode of the hydrogenated alloys after HIP and HT revealed cleavage fracture,indicating increased brittleness.In the as-built hydrogenated alloy,the fracture mode varied with location:brittle fracture occurred near the surface due to the formation of a hydride layer,while a more ductile fracture with dimples was observed below this layer.
基金financially supported by the Water and Land Resource Center(WLRC),Addis Ababa University(AAU),Water Security and Sustainable Development Hub funded by the UK Research and Innovation’s Global Challenges Research Fund(GCRF):ES/S008179/1.
文摘In many developing countries with poorly managed landscapes,soil erosion threatens the sustainability of water bodies.The main limitations of this study are the lack of daily sediment data,lithology,higher-resolution DEM data,and socioeconomic factors.Poor land use policy and resource management in the Upper Awash Sub-basin lead to soil erosion and sedimentation of hydrological infrastructure,Effective watershed prioritization requires integrating land use,hydrology,sediment load,and morphometric factors but often faces gaps,especially in the study area.This research aims to prioritise the Upper Awash Sub-Basin by its morphometric,land use and cover(LULC),and sediment yield characteristics.We used the integrated AHP-VIKOR multi-attribute decision-making method to prioritise watersheds,incorporating morphometry,LULC,and sediment load attributes in the simple matrix approach.The findings showed the following classes of erosion:exceedingly high(2722.14 km2),high(2524.46 km2),moderate(2205.48 km2),low(1611.43 km2),and extremely low(854.35 km2).Sub-watersheds WS6,WS8,WS10,WS13,and WS24 are the top priority for watershed management.The study ranked watersheds based on various attributes but encountered limitations such as the lack of daily sediment data,geological structure,and lithology.It can be concluded that this approach is very important to identify and categorize hotspots of soil erosion sub-watersheds for planners and decision-makers for conserving water and soil and for different environmental management purposes.
