This study investigates how cybersecurity can be enhanced through cloud computing solutions in the United States. The motive for this study is due to the rampant loss of data, breaches, and unauthorized access of inte...This study investigates how cybersecurity can be enhanced through cloud computing solutions in the United States. The motive for this study is due to the rampant loss of data, breaches, and unauthorized access of internet criminals in the United States. The study adopted a survey research design, collecting data from 890 cloud professionals with relevant knowledge of cybersecurity and cloud computing. A machine learning approach was adopted, specifically a random forest classifier, an ensemble, and a decision tree model. Out of the features in the data, ten important features were selected using random forest feature importance, which helps to achieve the objective of the study. The study’s purpose is to enable organizations to develop suitable techniques to prevent cybercrime using random forest predictions as they relate to cloud services in the United States. The effectiveness of the models used is evaluated by utilizing validation matrices that include recall values, accuracy, and precision, in addition to F1 scores and confusion matrices. Based on evaluation scores (accuracy, precision, recall, and F1 scores) of 81.9%, 82.6%, and 82.1%, the results demonstrated the effectiveness of the random forest model. It showed the importance of machine learning algorithms in preventing cybercrime and boosting security in the cloud environment. It recommends that other machine learning models be adopted to see how to improve cybersecurity through cloud computing.展开更多
Bangladesh is vulnerable to climate change-induced sea level rise due to its location and socioeconomic position. The study examines the Beel Kapalia region in polder no. 24 of the Monirampur upazila of Jessore distri...Bangladesh is vulnerable to climate change-induced sea level rise due to its location and socioeconomic position. The study examines the Beel Kapalia region in polder no. 24 of the Monirampur upazila of Jessore district, Khulna division. To assess local attitudes on sea level rise-related permanent flooding, Kapalia, Monoharpur, Nehalpur, Balidaha, and Panchakori were polled. This flooding has disrupted residents’ lifestyles, making them vulnerable to increasing sea levels. Viability and adaptability were assessed using livelihood capitals. Participants’ thoughts and knowledge about their resilience in several livelihood factors were gathered using participatory rural appraisal (PRA) instruments and a questionnaire survey in the area. Major discoveries include the impact of permanent floods on Beel Kapalia’s livelihoods, vulnerability and resilience assessments in numerous villages, and community viewpoints on regional adaptation methods to mitigate these consequences. The study found that a sustained 30.5 cm inundation would reduce local human, natural, physical, financial, and social capital resilience to 69.6%, 30.7%, 69.1%, 68.9%, and 69.1%. A constant 61 cm inundation would lower resistance to 40.9%, 8.7%, 42.4%, 45.6%, and 43.8%. Residents believe they can weather a 30.5 cm inundation with local adaptation measures, but if the water level rises to 61 cm, they may be displaced.展开更多
To prevent early bridge failures, effective Structural Health Monitoring (SHM) is vital. Vibration-based damage assessment is a powerful tool in this regard, as it relies on changes in a structure’s dynamic character...To prevent early bridge failures, effective Structural Health Monitoring (SHM) is vital. Vibration-based damage assessment is a powerful tool in this regard, as it relies on changes in a structure’s dynamic characteristics as it degrades. By measuring the vibration response of a bridge due to passing vehicles, this approach can identify potential structural damage. This dissertation introduces a novel technique grounded in Vehicle-Bridge Interaction (VBI) to evaluate bridge health. It aims to detect damage by analyzing the response of passing vehicles, taking into account VBI. The theoretical foundation of this method begins with representing the bridge’s superstructure using a Finite Element Model and employing a half-car dynamic model to simulate the vehicle with suspension. Two sets of motion equations, one for the bridge and one for the vehicle are generated using the Finite Element Method, mode superposition, and D’Alembert’s principle. The combined dynamics are solved using the Newmark-beta method, accounting for road surface roughness. A new approach for damage identification based on the response of passing vehicles is proposed. The response is theoretically composed of vehicle frequency, bridge natural frequency, and a pseudo-frequency component related to vehicle speed. The Empirical Mode Decomposition (EMD) method is applied to decompose the signal into its constituent parts, and damage detection relies on the Intrinsic Mode Functions (IMFs) corresponding to the vehicle speed component. This technique effectively identifies various damage scenarios considered in the study.展开更多
This experimental study aims to examine the influence of many crucial parameters on the workability and compressive strength of Ready-Mix Concrete (RMC). The study utilized two distinct varieties of superplasticizers ...This experimental study aims to examine the influence of many crucial parameters on the workability and compressive strength of Ready-Mix Concrete (RMC). The study utilized two distinct varieties of superplasticizers obtained from the local market. The fine aggregates utilized in this study were sourced from Sylhet sand, whereas the coarse aggregates were comprised of boulder crushed stone chips. The experimental procedures adhered to the requirements outlined by ASTM. A comprehensive investigation was conducted on a range of concrete compositions that used diverse chemical admixtures. The slump test was performed at regular intervals of 15 minutes until the slump value reached or fell below 3 cm after the mixing of the concrete. In the scenario involving two-stage admixture dosage, the second stage of admixture was introduced once the slump reached or dropped below 3 cm, following which the casting process was initiated. The process of curing concrete specimens consists of two distinct stages: the main stage and the final stage. Cylindrical specimens, with a diameter of 4 inches and a height of 8 inches, were manufactured for the purpose of evaluating their compressive strength at both 7 and 28 days. During the experimental trials, the water-cement (w/c) ratio was kept consistent, while different dosages of admixture were applied. The findings of the study indicate that the utilization of a two-stage dose of admixture resulted in enhanced and extended workability, along with higher strength of the concrete in comparison to specimens that did not incorporate any admixture. This research study enhances the comprehension of optimizing qualities of ready-mix concrete (RMC) by varying the superplasticizer, providing useful insights for the building sector.展开更多
Lactic acid bacteria (LAB) play a critical role in food, agricultural, and clinical applications. The fast growing characteristics of LAB and their metabolic activity have been the key in most applications including f...Lactic acid bacteria (LAB) play a critical role in food, agricultural, and clinical applications. The fast growing characteristics of LAB and their metabolic activity have been the key in most applications including food production, agricultural industry, and probiotics. However, the biochemical and biophysical environments have significant effect on the growth and metabolic activity of LAB. While the biochemical conditions are most likely established, controlling and optimizing of biochemical conditions have many limitations and challenges. In addition to selecting the right strain, desirable metabolic processes required optimizing and controlling the available nutrients including sugars, peptides, free amino acids, minerals, and vitamins in addition to buffering agents. Thus, much of research was conducted to understand the impact of available nutrients on the growth and metabolic activities of LAB. However, only a few nutritional parameters could be controlled at a time while holding other parameters constant. The nutritional parameters may also interact with each other resulting in faulty results. Characteristics of LAB such as fastidiousness in their nutritional requirements, ability to produce acid and antimicrobial compounds, and variations in the nutritional requirements among strains have added additional limitations and challenges in this regard. Thus, chemically defined media (CDM) were suggested to deal with different limitations and challenges. However, due to differences in growth conditions, results obtained in CDM may face some obstacles when it comes to industrial applications. Thus, this paper aimed to review the recent data in regard to the role of the nutritional requirements of LAB in optimizing and controlling metabolic activities and to discuss the associated limitations and challenges.展开更多
Near infrared (NIR) spectroscopy as a rapid and nondestructive analytical technique, integrated with chemometrics, is a powerful process analytical tool for the pharmaceutical industry and is becoming an attractive ...Near infrared (NIR) spectroscopy as a rapid and nondestructive analytical technique, integrated with chemometrics, is a powerful process analytical tool for the pharmaceutical industry and is becoming an attractive complementary technique for herbal medicine analysis. This review mainly focuses on the recent applications of NIR spectroscopy in species authentication of herbal medicines and their geo- graphical origin discrimination.展开更多
The electrochemical performance of a battery is considered to be primarily dependent on the electrode material. However, engineering and optimization of electrodes also play a crucial role, and the same electrode mate...The electrochemical performance of a battery is considered to be primarily dependent on the electrode material. However, engineering and optimization of electrodes also play a crucial role, and the same electrode material can be designed to offer significantly improved batteries. In this work, Si–Fe–Mn nanomaterial alloy(Si/alloy) and graphite composite electrodes were densified at different calendering conditions of 3, 5, and 8 tons, and its influence on electrode porosity, electrolyte wettability, and long-term cycling was investigated. The active material loading was maintained very high(~2 mg cm^(-2)) to implement electrode engineering close to commercial loading scales. The densification was optimized to balance between the electrode thickness and wettability to enable the best electrochemical properties of the Si/alloy anodes.In this case, engineering and optimizing the Si/alloy composite electrodes to 3 ton calendering(electrode densification from 0.39 to 0.48 g cm^(-3)) showed enhanced cycling stability with a high capacity retention of ~100% over 100 cycles.展开更多
Aqueous solutions of azo dyes undergo degradation to form harmless intermediates and colorless products following irradiation by visible light in the presence of titanium dioxide thin films. The dyes that were studied...Aqueous solutions of azo dyes undergo degradation to form harmless intermediates and colorless products following irradiation by visible light in the presence of titanium dioxide thin films. The dyes that were studied in this work are: Chicago Sky Blue 6B and Benzopurpurin 4B. Results obtained indicated that complete mineralization of the dyes took place under the experimental conditions. There was an increase in conductivity after the complete mineralization experiments possibly indicating the formation of ions such as NO3^- and SO4^2-. Chemical oxygen demand(COD) measurements show a decrease in organic matter for both dyes following complete degradation. The effect of how changing experimental conditions such as pH, temperature and starting concentrations of dyes affected the rate of dye degradation was measured. There was an increase in the rate of disappearance of the dye color at lower pH. High concentrations of dye solutions reauired Iona dearadation time.展开更多
Water quality indices (WQI) are useful tools for indicating the suitability of water for an expected use. However, they can suffer from some problems. The objective of this paper was to analyze the development of WQI ...Water quality indices (WQI) are useful tools for indicating the suitability of water for an expected use. However, they can suffer from some problems. The objective of this paper was to analyze the development of WQI to determine which parameters are used in water quality assessment and to discuss the characteristics of WQI. To screen articles on WQI, the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) method is applied to include or exclude articles. Four necessary steps are needed to design WQI: parameter selection, standardization, weighting and aggregation. A set of six methods of aggregations of sub-indices are identified: the arithmetic mean, the geometric mean, the root square, the logarithmic function, the fuzzy inference and the minimum operator. The problems encountered for the overall index are different according to the form of aggregation. They are eclipsing, ambiguity, rigidity or flexibility, adaptability and compensation. The chemical parameters (70%) are the most used in the development of WQI with the physical parameters used at 24% and the biological parameters at 6%. Dissolved oxygen (DO, 87%), total coliforms (87%), biological oxygen demand (BOD, 73%), pH (73%), temperature (67%), turbidity (60%), ammonia (53%), ammonium (47%) and total dissolved solids (47%) are the most commonly used parameters for water quality assessment.展开更多
The diamondback moth, Plutella xylostella L., has developed resistance to most insecticides used for its management. Suggested alternatives to forestall this process include biorational insecticides in mixtures with l...The diamondback moth, Plutella xylostella L., has developed resistance to most insecticides used for its management. Suggested alternatives to forestall this process include biorational insecticides in mixtures with low-risk insecticides. The aim of this study was to select an insecticide or insecticide mixture that could be adopted by small-scale growers for diamondback moth management. The effectiveness of four insecticide mixtures, i.e., Agroneem Plus (neem-derived), Spinosad (microbial origin), thiamethoxam (neonicotinoid) and a homemade methanol Jalapefio pepper extract, in laboratory bioassays was evaluated. Binary mixtures were tested against single products at manufacturer's label rates. These were applied to collard greens using the leaf dip method and fed to the newly molted 2nd or 3rd instar larvae. Mixtures were evaluated for efficacy based on larval mortality and consumption of leaf discs. The results showed interactions between Jalapefio pepper extract and Spinosad and between the neem-derived Agroneem Plus and thiamethoxam at some of the tested concentrations. Mixtures with at any amount of Spinosad killed all larvae. The neem-based product gave inconsistent results in some treatments; in some case, increased leaf damage did not result in commensurate larval mortalities. The reported resistance of diamondback moth larvae to Spinosad was not observed during this study, neither with Spinosad alone nor in mixtures.展开更多
A community-based sheep cross breeding project was conducted in Ethiopia with exotic Awassi crossbred rams and less productive indigenous Tikur ewes.Fifty-five Awassi crossbred rams having 46,48,56 and 65%Awassi blood...A community-based sheep cross breeding project was conducted in Ethiopia with exotic Awassi crossbred rams and less productive indigenous Tikur ewes.Fifty-five Awassi crossbred rams having 46,48,56 and 65%Awassi blood levels were purchased and distributed to the participating 84 farmers which had 2,884 breeding ewes.The overall least square mean weights for F1 and F2 generation lambs at birth,day 90,180,270 and yearling weight were 3.10±0.01,13.04±0.07,16.95±0.08,20.84±0.11 and 24.42±0.14 kg,respectively.Body weight traits were significantly affected by lambing year for birth weight(P<0.05),180-day(d)weight(P<0.05),270-d weight(P<0.001)and 360 d(yearling)weight(P<0.001)but no effect(P>0.05)was noted for 90-d weight(weaning weight).Season of lambing had significant effect(P<0.01)only for birth weight.There was a significant difference(P<0.001)among the different villages for birth weight,and for day 90,180,270 and 360 body weights.The study showed that crossing Awassi crossbred rams with Tikur ewes can improve birth weight by 71.27%,90-d weight by 76.78%,180-d weight by 63.45%and yearling weight by 76.06%under farmer management practices.Results revealed that crossing Awassi crossbred rams with blood level of 56%and above with local Tikur ewes resulted in superior progenies that can fulfill export live weight standard of 25 kg at yearling weight.The future of Awassi-Tikur sheep farming must focus on feed supplementation strategies and on establishing cooperatives for farmers to improve their livelihoods.展开更多
Construction on soft soil is one of the most challenging situations faced by geotechnical engineers. The heterogeneous and complex nature of soil, especially those containing organic clay, often makes it impossible fo...Construction on soft soil is one of the most challenging situations faced by geotechnical engineers. The heterogeneous and complex nature of soil, especially those containing organic clay, often makes it impossible for the construction specification to be addressed properly. Generally, clay exhibits low strength, high compressibility, and strength reduction when subjected to mechanical disturbance. This means that construction on clay soil is vulnerable to bearing capacity failure induced by low inherent shear strength. All these properties can be improved by the effective stabilization of soil. This study analyzed the effectiveness of incorporating salt-lime mixtures at various dosages in improving the strength increment of the soil. The results indicate that among different combinations of salt and lime, the best performance in terms of strength increase was achieved by adding 10% NaCl with 3% lime in the soil. The outcome of this study focuses on enhancing the ultimate strength of soil and its implementation in the field of foundation engineering.展开更多
Peanut is an energy dense food item and it contains a substantial amount of fat,proteins,carbohydrate,both fat soluble and water soluble vitamins,minerals and phytochemicals.Peanuts are consumed worldwide due to its h...Peanut is an energy dense food item and it contains a substantial amount of fat,proteins,carbohydrate,both fat soluble and water soluble vitamins,minerals and phytochemicals.Peanuts are consumed worldwide due to its high nutritional value and pleasant or unique flavor after roasting or boiling.The lipid,protein and carbohydrate not only provide energy,but also provide essential nutrients for normal body functions such as body fat and muscle buildup.Vitamins are needed for normal cell function,growth,development,disease prevention and act as coenzymes during the production of energy.Due to the high nutrient contents of peanuts,they have been used to combat malnutrition in most developing countries.Epidemiologic studies have associated nut consumption with a reduced incidence of cardiovascular heart diseases and gallstones in both genders and diabetes in women.Limited evidence also suggests beneficial effects on hypertension,cancer,and inflammation.The health risk associated with peanut consumption is allergy in developed countries.The review discusses the health aspects,including allergy,of peanut consumption as they related to the chemical composition of peanuts using literatures published in past two decades with exceptions of a few older articles.展开更多
In smart industrial systems,in many cases,a fault can be captured as an event to represent the distinct nature of subsequent changes.Event-based fault diagnosis techniques are capable model-based methods for diagnosin...In smart industrial systems,in many cases,a fault can be captured as an event to represent the distinct nature of subsequent changes.Event-based fault diagnosis techniques are capable model-based methods for diagnosing faults from a sequence of observable events executed by the system under diagnosis.Most event-based diagnosis techniques rely on perfect observations of observable events.However,in practice,it is common to miss an observable event due to a problem in sensorreadings or communication/transmission channels.This paper develops a fault diagnosis tool,referred to as diagnoser,which can robustly detect,locate,and isolate occurred faults.The developed diagnoser is resilient against missed observations.A missed observation is detected from its successive sequence of events.Upon detecting a missed observation,the developed diagnoser automatically resets and then,asynchronously resumes the diagnosis process.This is achieved solely based on postreset/activation observations and without interrupting the performance of the system under diagnosis.New concepts of asynchronous detectability and asynchronous diagnosability are introduced.It is shown that if asynchronous detectability and asynchronous diagnosability hold,the proposed diagnoser is capable of diagnosing occurred faults under imperfect observations.The proposed technique is applied to diagnose faults in a manufacturing process.Illustrative examples are provided to explain the details of the proposed algorithm.The result paves the way towards fostering resilient cyber-physical systems in Industry4.0 context.展开更多
This article reviews nanotechnology as a practical solution for improving lithium-sulfur batteries. Lithiumsulfur batteries have been widely examined because sulfur has many advantageous properties such as a high crus...This article reviews nanotechnology as a practical solution for improving lithium-sulfur batteries. Lithiumsulfur batteries have been widely examined because sulfur has many advantageous properties such as a high crustal abundance, low environmental impact, low cost, high gravimetric(2600 W h kg-1) and volumetric(2800 W h L-1) energy densities, assuming complete conversion of sulfur to lithium sulfide(Li2S)upon lithiation. However, lithium-sulfur batteries have not yet reach commercialization due to demerits involving the formation of soluble lithium polysulfides(Li2Sn, n=3–8), low electrical conductivity, and low loading density of sulfur. These issues arise mainly due to the polysulfide shuttle phenomenon and the inherent insulating nature of sulfur. To overcome these issues, strategies have been pursued using nanotechnology applied to porous carbon nanocomposites, hollow one-dimensional carbon nanomaterials, graphene nanocomposites, and three-dimensional carbon nanostructured matrices. This paper aims to review various solutions pertaining to the role of nanotechnology in synthesizing nanoscale and nanostructured materials for advanced and high-performance lithium–sulfur batteries. Furthermore, we highlight perspective research directions for commercialization of lithium–sulfur batteries as a major power source for electric vehicles and large-scale electric energy storage.展开更多
Increasing evidence has shown that gut microbiota plays important roles in metabolizing large molecular polyphenols to bioavailable and bioactive microbial metabolites.Theaflavin(TF)is one of the major color compounds...Increasing evidence has shown that gut microbiota plays important roles in metabolizing large molecular polyphenols to bioavailable and bioactive microbial metabolites.Theaflavin(TF)is one of the major color compounds in black tea and has demonstrated anti-inflammation,antioxidant,and anticancer effects properties.However,little is known about the metabolism of TF by gut microbiota in vivo.In this study,following the administration of TF to mice,the C-ring cleavage metabolites,dihydro-and tetrahydro-theaflavin(DH-TF and TH-TF)were detected in mouse feces by LC-MS and validated by authentic standards from in situ chemical reaction.The observation of the C-ring cleavage metabolites in TF-treated conventionalized mice but not in germ-free(GF)mice confirmed the role of gut microbiota in cleaving the C-rings of TF.The detection of DH-TF from the anaerobic incubation of TF with catechin-converting gut bacteria,Eggerthella lenta(Eggerth),suggested that the microbes with the capacity to cleave the C-ring of catechins were able to metabolize TF following the same mechanism.Additionally,three small phenolic metabolites were detected in mouse feces,and one of them was primarily detected in SPF mice not GF mice,which revealed that TF,subsequent to the cleaved C-ring,can be further metabolized into smaller phenolic metabolites by gut microbiota.Dose-dependent production of these metabolites were observed from the administration of 100 mg/kg to 400 mg/kg body weight of TF.In conclusion,gut microbiota can metabolize TF to the open-ring metabolites and the phenolic metabolites through the C-ring cleavage in mice.展开更多
Due to the accumulation of an enormous amount of plastic waste from municipal and industrial sources in landfills,landfill leachate is becoming a significant reservoir of microplastics.The release of microplastics fro...Due to the accumulation of an enormous amount of plastic waste from municipal and industrial sources in landfills,landfill leachate is becoming a significant reservoir of microplastics.The release of microplastics from landfill leachate into the environment can have undesirable effects on humans and biota.This study provides the state of the science regarding the source,detection,occurrence,and remediation of microplastics in landfill leachate based on a comprehensive review of the scientific literature,mostly in the recent decade.Solid waste and wastewater treatment residue are the primary sources of microplastics in landfill leachate.Microplastic concentration in raw and treated landfill leachate varied between 0-382 and 0-2.7 items L^(−1).Microplastics in raw landfill leachate are largely attributable to local plastic waste production and solid waste management practices.Polyethylene,polystyrene,and polypropylene are the most prevalent microplastic polymers in landfill leachate.Even though the colors of microplastics are primarily determined by their parent plastic waste,the predominance of light-colored microplastics in landfill leachate indicates long-term degradation.The identified morphologies of microplastics in leachate from all published sources contain fiber and fragments the most.Depending on the treatment method,leachate treatment processes can achieve microplastic removal rates between 3%and 100%.The review also provides unique perspectives on microplastics in landfill leachate in terms of remediation,final disposal,fate and transport among engineering systems,and source reduction,etc.The landfill-wastewater treatment plant loop and bioreactor landfills present unique difficulties and opportunities for managing microplastics induced by landfill leachate.展开更多
Water resources face many pressures and stresses around the world.Assessing the vulnerability of water resources is,therefore,increasingly an essential practice in water resources management.Several studies of water r...Water resources face many pressures and stresses around the world.Assessing the vulnerability of water resources is,therefore,increasingly an essential practice in water resources management.Several studies of water resources vulnerability have been carried out around the world during the last three decades.Thus,the main objective of this study was to analyze water resources vulnerability assessment tools and identify the methodological trend of water resources vulnerability assessment at the local level in existing literature.To achieve this objective,the Preferred Reporting Items for Systematic Reviews and Meta-Analyses(PRISMA)method has been applied to include or exclude articles.Articles on water vulnerability numbering 374 were preselected in the ScienceDirect and the Google Scholar databases.Only 32 out of the 374 articles met the inclusion criteria defined for the analysis.The results show that China(21.9%),U.S.A.(9.4%)and Canada(6.3%)are the most active countries publishing water resources vulnerability assessments.Some 191 vulnerability indicators from the 32 articles were classified into five categories of factors:physical factors(33.5%),socio-economic factors(28.3%),environmental or eco-environmental factors(25.1%),institutions and governance factors(7.3%)and infrastructure factors(5.8%).This study shows that almost half of the studies(47%)considered all five categories of factors,9.4%considered four categories of factors,6.3%considered three categories of factors,28%used two types of factors and 9.4%considered only one category.Researchers have used several methods to assess water resources vulnerability:overlay and index methods(59.4%),process-based models(12.5%),statistical methods(9.4%),overlay and index methods plus process-based model(9.4%),overlay and index methods plus statistical methods(6.3%)and statistical methods plus process-based models(3.1%).Geographic information system(GIS)is an important tool in assessing the vulnerability of water resources with almost 60%of the studies using it at some stage of the assessment.In recent years,there is an increasing trend toward conceptualizing the vulnerability of water resources in a holistic way.展开更多
Mercury is ranked 3^(rd)as a global pollutant because of its long persistence in the environment. Approximately 65% of its anthropogenic emission (Hg^(0)) to the atmosphere is from coal-thermal power plants. Thus, the...Mercury is ranked 3^(rd)as a global pollutant because of its long persistence in the environment. Approximately 65% of its anthropogenic emission (Hg^(0)) to the atmosphere is from coal-thermal power plants. Thus, the Hg^(0)emission control from coal-thermal power plants is inevitable. Therefore, multiple sorbent materials were synthesized using a one-step pyrolysis method to capture the Hg^(0)from simulated coal syngas. Results showed, the Hg^(0)removal performance of the sorbents increased by the citric acid/ultrasonic application.T5CUF_(0.3)demonstrated the highest Hg^(0)capturing performance with an adsorption capacity of 106.81 μg/g within 60 min at 200 °C under complex simulated syngas mixture (20% CO,20% H_(2), 10 ppm V HCl, 6% H_(2)O, and 400 ppm V H_(2)S). The Hg^(0)removal mechanism was proposed, revealing that the chemisorption governs the Hg^(0)removal process. Besides, the active Hg^(0)removal performance is attributed to the high dispersion of valence Fe_(3)O_(4)and lattice oxygen (α) contents over the T5CUF_(0.3)surface. In addition, the temperature programmed desorption (TPD) and XPS analysis confirmed that H_(2)S/HCl gases generate active sites over the sorbent surface, facilitating high Hg^(0)adsorption from syngas. This work represented a facile and practical pathway for utilizing cheap and eco-friendly tea waste to control the Hg^(0)emission.展开更多
文摘This study investigates how cybersecurity can be enhanced through cloud computing solutions in the United States. The motive for this study is due to the rampant loss of data, breaches, and unauthorized access of internet criminals in the United States. The study adopted a survey research design, collecting data from 890 cloud professionals with relevant knowledge of cybersecurity and cloud computing. A machine learning approach was adopted, specifically a random forest classifier, an ensemble, and a decision tree model. Out of the features in the data, ten important features were selected using random forest feature importance, which helps to achieve the objective of the study. The study’s purpose is to enable organizations to develop suitable techniques to prevent cybercrime using random forest predictions as they relate to cloud services in the United States. The effectiveness of the models used is evaluated by utilizing validation matrices that include recall values, accuracy, and precision, in addition to F1 scores and confusion matrices. Based on evaluation scores (accuracy, precision, recall, and F1 scores) of 81.9%, 82.6%, and 82.1%, the results demonstrated the effectiveness of the random forest model. It showed the importance of machine learning algorithms in preventing cybercrime and boosting security in the cloud environment. It recommends that other machine learning models be adopted to see how to improve cybersecurity through cloud computing.
文摘Bangladesh is vulnerable to climate change-induced sea level rise due to its location and socioeconomic position. The study examines the Beel Kapalia region in polder no. 24 of the Monirampur upazila of Jessore district, Khulna division. To assess local attitudes on sea level rise-related permanent flooding, Kapalia, Monoharpur, Nehalpur, Balidaha, and Panchakori were polled. This flooding has disrupted residents’ lifestyles, making them vulnerable to increasing sea levels. Viability and adaptability were assessed using livelihood capitals. Participants’ thoughts and knowledge about their resilience in several livelihood factors were gathered using participatory rural appraisal (PRA) instruments and a questionnaire survey in the area. Major discoveries include the impact of permanent floods on Beel Kapalia’s livelihoods, vulnerability and resilience assessments in numerous villages, and community viewpoints on regional adaptation methods to mitigate these consequences. The study found that a sustained 30.5 cm inundation would reduce local human, natural, physical, financial, and social capital resilience to 69.6%, 30.7%, 69.1%, 68.9%, and 69.1%. A constant 61 cm inundation would lower resistance to 40.9%, 8.7%, 42.4%, 45.6%, and 43.8%. Residents believe they can weather a 30.5 cm inundation with local adaptation measures, but if the water level rises to 61 cm, they may be displaced.
文摘To prevent early bridge failures, effective Structural Health Monitoring (SHM) is vital. Vibration-based damage assessment is a powerful tool in this regard, as it relies on changes in a structure’s dynamic characteristics as it degrades. By measuring the vibration response of a bridge due to passing vehicles, this approach can identify potential structural damage. This dissertation introduces a novel technique grounded in Vehicle-Bridge Interaction (VBI) to evaluate bridge health. It aims to detect damage by analyzing the response of passing vehicles, taking into account VBI. The theoretical foundation of this method begins with representing the bridge’s superstructure using a Finite Element Model and employing a half-car dynamic model to simulate the vehicle with suspension. Two sets of motion equations, one for the bridge and one for the vehicle are generated using the Finite Element Method, mode superposition, and D’Alembert’s principle. The combined dynamics are solved using the Newmark-beta method, accounting for road surface roughness. A new approach for damage identification based on the response of passing vehicles is proposed. The response is theoretically composed of vehicle frequency, bridge natural frequency, and a pseudo-frequency component related to vehicle speed. The Empirical Mode Decomposition (EMD) method is applied to decompose the signal into its constituent parts, and damage detection relies on the Intrinsic Mode Functions (IMFs) corresponding to the vehicle speed component. This technique effectively identifies various damage scenarios considered in the study.
文摘This experimental study aims to examine the influence of many crucial parameters on the workability and compressive strength of Ready-Mix Concrete (RMC). The study utilized two distinct varieties of superplasticizers obtained from the local market. The fine aggregates utilized in this study were sourced from Sylhet sand, whereas the coarse aggregates were comprised of boulder crushed stone chips. The experimental procedures adhered to the requirements outlined by ASTM. A comprehensive investigation was conducted on a range of concrete compositions that used diverse chemical admixtures. The slump test was performed at regular intervals of 15 minutes until the slump value reached or fell below 3 cm after the mixing of the concrete. In the scenario involving two-stage admixture dosage, the second stage of admixture was introduced once the slump reached or dropped below 3 cm, following which the casting process was initiated. The process of curing concrete specimens consists of two distinct stages: the main stage and the final stage. Cylindrical specimens, with a diameter of 4 inches and a height of 8 inches, were manufactured for the purpose of evaluating their compressive strength at both 7 and 28 days. During the experimental trials, the water-cement (w/c) ratio was kept consistent, while different dosages of admixture were applied. The findings of the study indicate that the utilization of a two-stage dose of admixture resulted in enhanced and extended workability, along with higher strength of the concrete in comparison to specimens that did not incorporate any admixture. This research study enhances the comprehension of optimizing qualities of ready-mix concrete (RMC) by varying the superplasticizer, providing useful insights for the building sector.
文摘Lactic acid bacteria (LAB) play a critical role in food, agricultural, and clinical applications. The fast growing characteristics of LAB and their metabolic activity have been the key in most applications including food production, agricultural industry, and probiotics. However, the biochemical and biophysical environments have significant effect on the growth and metabolic activity of LAB. While the biochemical conditions are most likely established, controlling and optimizing of biochemical conditions have many limitations and challenges. In addition to selecting the right strain, desirable metabolic processes required optimizing and controlling the available nutrients including sugars, peptides, free amino acids, minerals, and vitamins in addition to buffering agents. Thus, much of research was conducted to understand the impact of available nutrients on the growth and metabolic activities of LAB. However, only a few nutritional parameters could be controlled at a time while holding other parameters constant. The nutritional parameters may also interact with each other resulting in faulty results. Characteristics of LAB such as fastidiousness in their nutritional requirements, ability to produce acid and antimicrobial compounds, and variations in the nutritional requirements among strains have added additional limitations and challenges in this regard. Thus, chemically defined media (CDM) were suggested to deal with different limitations and challenges. However, due to differences in growth conditions, results obtained in CDM may face some obstacles when it comes to industrial applications. Thus, this paper aimed to review the recent data in regard to the role of the nutritional requirements of LAB in optimizing and controlling metabolic activities and to discuss the associated limitations and challenges.
基金financial support from the National Natural Science Foundation of China(no.81373926)
文摘Near infrared (NIR) spectroscopy as a rapid and nondestructive analytical technique, integrated with chemometrics, is a powerful process analytical tool for the pharmaceutical industry and is becoming an attractive complementary technique for herbal medicine analysis. This review mainly focuses on the recent applications of NIR spectroscopy in species authentication of herbal medicines and their geo- graphical origin discrimination.
基金financial support from Joint School of Nanoscience and Nanoengineering,USA
文摘The electrochemical performance of a battery is considered to be primarily dependent on the electrode material. However, engineering and optimization of electrodes also play a crucial role, and the same electrode material can be designed to offer significantly improved batteries. In this work, Si–Fe–Mn nanomaterial alloy(Si/alloy) and graphite composite electrodes were densified at different calendering conditions of 3, 5, and 8 tons, and its influence on electrode porosity, electrolyte wettability, and long-term cycling was investigated. The active material loading was maintained very high(~2 mg cm^(-2)) to implement electrode engineering close to commercial loading scales. The densification was optimized to balance between the electrode thickness and wettability to enable the best electrochemical properties of the Si/alloy anodes.In this case, engineering and optimizing the Si/alloy composite electrodes to 3 ton calendering(electrode densification from 0.39 to 0.48 g cm^(-3)) showed enhanced cycling stability with a high capacity retention of ~100% over 100 cycles.
文摘Aqueous solutions of azo dyes undergo degradation to form harmless intermediates and colorless products following irradiation by visible light in the presence of titanium dioxide thin films. The dyes that were studied in this work are: Chicago Sky Blue 6B and Benzopurpurin 4B. Results obtained indicated that complete mineralization of the dyes took place under the experimental conditions. There was an increase in conductivity after the complete mineralization experiments possibly indicating the formation of ions such as NO3^- and SO4^2-. Chemical oxygen demand(COD) measurements show a decrease in organic matter for both dyes following complete degradation. The effect of how changing experimental conditions such as pH, temperature and starting concentrations of dyes affected the rate of dye degradation was measured. There was an increase in the rate of disappearance of the dye color at lower pH. High concentrations of dye solutions reauired Iona dearadation time.
文摘Water quality indices (WQI) are useful tools for indicating the suitability of water for an expected use. However, they can suffer from some problems. The objective of this paper was to analyze the development of WQI to determine which parameters are used in water quality assessment and to discuss the characteristics of WQI. To screen articles on WQI, the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) method is applied to include or exclude articles. Four necessary steps are needed to design WQI: parameter selection, standardization, weighting and aggregation. A set of six methods of aggregations of sub-indices are identified: the arithmetic mean, the geometric mean, the root square, the logarithmic function, the fuzzy inference and the minimum operator. The problems encountered for the overall index are different according to the form of aggregation. They are eclipsing, ambiguity, rigidity or flexibility, adaptability and compensation. The chemical parameters (70%) are the most used in the development of WQI with the physical parameters used at 24% and the biological parameters at 6%. Dissolved oxygen (DO, 87%), total coliforms (87%), biological oxygen demand (BOD, 73%), pH (73%), temperature (67%), turbidity (60%), ammonia (53%), ammonium (47%) and total dissolved solids (47%) are the most commonly used parameters for water quality assessment.
文摘The diamondback moth, Plutella xylostella L., has developed resistance to most insecticides used for its management. Suggested alternatives to forestall this process include biorational insecticides in mixtures with low-risk insecticides. The aim of this study was to select an insecticide or insecticide mixture that could be adopted by small-scale growers for diamondback moth management. The effectiveness of four insecticide mixtures, i.e., Agroneem Plus (neem-derived), Spinosad (microbial origin), thiamethoxam (neonicotinoid) and a homemade methanol Jalapefio pepper extract, in laboratory bioassays was evaluated. Binary mixtures were tested against single products at manufacturer's label rates. These were applied to collard greens using the leaf dip method and fed to the newly molted 2nd or 3rd instar larvae. Mixtures were evaluated for efficacy based on larval mortality and consumption of leaf discs. The results showed interactions between Jalapefio pepper extract and Spinosad and between the neem-derived Agroneem Plus and thiamethoxam at some of the tested concentrations. Mixtures with at any amount of Spinosad killed all larvae. The neem-based product gave inconsistent results in some treatments; in some case, increased leaf damage did not result in commensurate larval mortalities. The reported resistance of diamondback moth larvae to Spinosad was not observed during this study, neither with Spinosad alone nor in mixtures.
文摘A community-based sheep cross breeding project was conducted in Ethiopia with exotic Awassi crossbred rams and less productive indigenous Tikur ewes.Fifty-five Awassi crossbred rams having 46,48,56 and 65%Awassi blood levels were purchased and distributed to the participating 84 farmers which had 2,884 breeding ewes.The overall least square mean weights for F1 and F2 generation lambs at birth,day 90,180,270 and yearling weight were 3.10±0.01,13.04±0.07,16.95±0.08,20.84±0.11 and 24.42±0.14 kg,respectively.Body weight traits were significantly affected by lambing year for birth weight(P<0.05),180-day(d)weight(P<0.05),270-d weight(P<0.001)and 360 d(yearling)weight(P<0.001)but no effect(P>0.05)was noted for 90-d weight(weaning weight).Season of lambing had significant effect(P<0.01)only for birth weight.There was a significant difference(P<0.001)among the different villages for birth weight,and for day 90,180,270 and 360 body weights.The study showed that crossing Awassi crossbred rams with Tikur ewes can improve birth weight by 71.27%,90-d weight by 76.78%,180-d weight by 63.45%and yearling weight by 76.06%under farmer management practices.Results revealed that crossing Awassi crossbred rams with blood level of 56%and above with local Tikur ewes resulted in superior progenies that can fulfill export live weight standard of 25 kg at yearling weight.The future of Awassi-Tikur sheep farming must focus on feed supplementation strategies and on establishing cooperatives for farmers to improve their livelihoods.
文摘Construction on soft soil is one of the most challenging situations faced by geotechnical engineers. The heterogeneous and complex nature of soil, especially those containing organic clay, often makes it impossible for the construction specification to be addressed properly. Generally, clay exhibits low strength, high compressibility, and strength reduction when subjected to mechanical disturbance. This means that construction on clay soil is vulnerable to bearing capacity failure induced by low inherent shear strength. All these properties can be improved by the effective stabilization of soil. This study analyzed the effectiveness of incorporating salt-lime mixtures at various dosages in improving the strength increment of the soil. The results indicate that among different combinations of salt and lime, the best performance in terms of strength increase was achieved by adding 10% NaCl with 3% lime in the soil. The outcome of this study focuses on enhancing the ultimate strength of soil and its implementation in the field of foundation engineering.
文摘Peanut is an energy dense food item and it contains a substantial amount of fat,proteins,carbohydrate,both fat soluble and water soluble vitamins,minerals and phytochemicals.Peanuts are consumed worldwide due to its high nutritional value and pleasant or unique flavor after roasting or boiling.The lipid,protein and carbohydrate not only provide energy,but also provide essential nutrients for normal body functions such as body fat and muscle buildup.Vitamins are needed for normal cell function,growth,development,disease prevention and act as coenzymes during the production of energy.Due to the high nutrient contents of peanuts,they have been used to combat malnutrition in most developing countries.Epidemiologic studies have associated nut consumption with a reduced incidence of cardiovascular heart diseases and gallstones in both genders and diabetes in women.Limited evidence also suggests beneficial effects on hypertension,cancer,and inflammation.The health risk associated with peanut consumption is allergy in developed countries.The review discusses the health aspects,including allergy,of peanut consumption as they related to the chemical composition of peanuts using literatures published in past two decades with exceptions of a few older articles.
基金the National Science Foundation(NSF)(1832110 and 2000320)Air Force Research Laboratory(AFRL)and Office of the Secretary of Defense(OSD)(FA8750-15-2-0116).
文摘In smart industrial systems,in many cases,a fault can be captured as an event to represent the distinct nature of subsequent changes.Event-based fault diagnosis techniques are capable model-based methods for diagnosing faults from a sequence of observable events executed by the system under diagnosis.Most event-based diagnosis techniques rely on perfect observations of observable events.However,in practice,it is common to miss an observable event due to a problem in sensorreadings or communication/transmission channels.This paper develops a fault diagnosis tool,referred to as diagnoser,which can robustly detect,locate,and isolate occurred faults.The developed diagnoser is resilient against missed observations.A missed observation is detected from its successive sequence of events.Upon detecting a missed observation,the developed diagnoser automatically resets and then,asynchronously resumes the diagnosis process.This is achieved solely based on postreset/activation observations and without interrupting the performance of the system under diagnosis.New concepts of asynchronous detectability and asynchronous diagnosability are introduced.It is shown that if asynchronous detectability and asynchronous diagnosability hold,the proposed diagnoser is capable of diagnosing occurred faults under imperfect observations.The proposed technique is applied to diagnose faults in a manufacturing process.Illustrative examples are provided to explain the details of the proposed algorithm.The result paves the way towards fostering resilient cyber-physical systems in Industry4.0 context.
文摘This article reviews nanotechnology as a practical solution for improving lithium-sulfur batteries. Lithiumsulfur batteries have been widely examined because sulfur has many advantageous properties such as a high crustal abundance, low environmental impact, low cost, high gravimetric(2600 W h kg-1) and volumetric(2800 W h L-1) energy densities, assuming complete conversion of sulfur to lithium sulfide(Li2S)upon lithiation. However, lithium-sulfur batteries have not yet reach commercialization due to demerits involving the formation of soluble lithium polysulfides(Li2Sn, n=3–8), low electrical conductivity, and low loading density of sulfur. These issues arise mainly due to the polysulfide shuttle phenomenon and the inherent insulating nature of sulfur. To overcome these issues, strategies have been pursued using nanotechnology applied to porous carbon nanocomposites, hollow one-dimensional carbon nanomaterials, graphene nanocomposites, and three-dimensional carbon nanostructured matrices. This paper aims to review various solutions pertaining to the role of nanotechnology in synthesizing nanoscale and nanostructured materials for advanced and high-performance lithium–sulfur batteries. Furthermore, we highlight perspective research directions for commercialization of lithium–sulfur batteries as a major power source for electric vehicles and large-scale electric energy storage.
文摘Increasing evidence has shown that gut microbiota plays important roles in metabolizing large molecular polyphenols to bioavailable and bioactive microbial metabolites.Theaflavin(TF)is one of the major color compounds in black tea and has demonstrated anti-inflammation,antioxidant,and anticancer effects properties.However,little is known about the metabolism of TF by gut microbiota in vivo.In this study,following the administration of TF to mice,the C-ring cleavage metabolites,dihydro-and tetrahydro-theaflavin(DH-TF and TH-TF)were detected in mouse feces by LC-MS and validated by authentic standards from in situ chemical reaction.The observation of the C-ring cleavage metabolites in TF-treated conventionalized mice but not in germ-free(GF)mice confirmed the role of gut microbiota in cleaving the C-rings of TF.The detection of DH-TF from the anaerobic incubation of TF with catechin-converting gut bacteria,Eggerthella lenta(Eggerth),suggested that the microbes with the capacity to cleave the C-ring of catechins were able to metabolize TF following the same mechanism.Additionally,three small phenolic metabolites were detected in mouse feces,and one of them was primarily detected in SPF mice not GF mice,which revealed that TF,subsequent to the cleaved C-ring,can be further metabolized into smaller phenolic metabolites by gut microbiota.Dose-dependent production of these metabolites were observed from the administration of 100 mg/kg to 400 mg/kg body weight of TF.In conclusion,gut microbiota can metabolize TF to the open-ring metabolites and the phenolic metabolites through the C-ring cleavage in mice.
基金This work is financially supported by a grant sponsored by the National Science Foundation,award number 2101053,and a grant sponsored by the North Carolina Attorney General Office's Environmental Enhancement Grant titled“Environmental Impacts of Landfill Induced Anthropogenic Dissolved Organic Nitrogen in Eastern North Carolina Estuaries”.
文摘Due to the accumulation of an enormous amount of plastic waste from municipal and industrial sources in landfills,landfill leachate is becoming a significant reservoir of microplastics.The release of microplastics from landfill leachate into the environment can have undesirable effects on humans and biota.This study provides the state of the science regarding the source,detection,occurrence,and remediation of microplastics in landfill leachate based on a comprehensive review of the scientific literature,mostly in the recent decade.Solid waste and wastewater treatment residue are the primary sources of microplastics in landfill leachate.Microplastic concentration in raw and treated landfill leachate varied between 0-382 and 0-2.7 items L^(−1).Microplastics in raw landfill leachate are largely attributable to local plastic waste production and solid waste management practices.Polyethylene,polystyrene,and polypropylene are the most prevalent microplastic polymers in landfill leachate.Even though the colors of microplastics are primarily determined by their parent plastic waste,the predominance of light-colored microplastics in landfill leachate indicates long-term degradation.The identified morphologies of microplastics in leachate from all published sources contain fiber and fragments the most.Depending on the treatment method,leachate treatment processes can achieve microplastic removal rates between 3%and 100%.The review also provides unique perspectives on microplastics in landfill leachate in terms of remediation,final disposal,fate and transport among engineering systems,and source reduction,etc.The landfill-wastewater treatment plant loop and bioreactor landfills present unique difficulties and opportunities for managing microplastics induced by landfill leachate.
文摘Water resources face many pressures and stresses around the world.Assessing the vulnerability of water resources is,therefore,increasingly an essential practice in water resources management.Several studies of water resources vulnerability have been carried out around the world during the last three decades.Thus,the main objective of this study was to analyze water resources vulnerability assessment tools and identify the methodological trend of water resources vulnerability assessment at the local level in existing literature.To achieve this objective,the Preferred Reporting Items for Systematic Reviews and Meta-Analyses(PRISMA)method has been applied to include or exclude articles.Articles on water vulnerability numbering 374 were preselected in the ScienceDirect and the Google Scholar databases.Only 32 out of the 374 articles met the inclusion criteria defined for the analysis.The results show that China(21.9%),U.S.A.(9.4%)and Canada(6.3%)are the most active countries publishing water resources vulnerability assessments.Some 191 vulnerability indicators from the 32 articles were classified into five categories of factors:physical factors(33.5%),socio-economic factors(28.3%),environmental or eco-environmental factors(25.1%),institutions and governance factors(7.3%)and infrastructure factors(5.8%).This study shows that almost half of the studies(47%)considered all five categories of factors,9.4%considered four categories of factors,6.3%considered three categories of factors,28%used two types of factors and 9.4%considered only one category.Researchers have used several methods to assess water resources vulnerability:overlay and index methods(59.4%),process-based models(12.5%),statistical methods(9.4%),overlay and index methods plus process-based model(9.4%),overlay and index methods plus statistical methods(6.3%)and statistical methods plus process-based models(3.1%).Geographic information system(GIS)is an important tool in assessing the vulnerability of water resources with almost 60%of the studies using it at some stage of the assessment.In recent years,there is an increasing trend toward conceptualizing the vulnerability of water resources in a holistic way.
基金supported by the Natural Science Basic Research Plan in Shaanxi Province of China (No. 2019JLM-13)。
文摘Mercury is ranked 3^(rd)as a global pollutant because of its long persistence in the environment. Approximately 65% of its anthropogenic emission (Hg^(0)) to the atmosphere is from coal-thermal power plants. Thus, the Hg^(0)emission control from coal-thermal power plants is inevitable. Therefore, multiple sorbent materials were synthesized using a one-step pyrolysis method to capture the Hg^(0)from simulated coal syngas. Results showed, the Hg^(0)removal performance of the sorbents increased by the citric acid/ultrasonic application.T5CUF_(0.3)demonstrated the highest Hg^(0)capturing performance with an adsorption capacity of 106.81 μg/g within 60 min at 200 °C under complex simulated syngas mixture (20% CO,20% H_(2), 10 ppm V HCl, 6% H_(2)O, and 400 ppm V H_(2)S). The Hg^(0)removal mechanism was proposed, revealing that the chemisorption governs the Hg^(0)removal process. Besides, the active Hg^(0)removal performance is attributed to the high dispersion of valence Fe_(3)O_(4)and lattice oxygen (α) contents over the T5CUF_(0.3)surface. In addition, the temperature programmed desorption (TPD) and XPS analysis confirmed that H_(2)S/HCl gases generate active sites over the sorbent surface, facilitating high Hg^(0)adsorption from syngas. This work represented a facile and practical pathway for utilizing cheap and eco-friendly tea waste to control the Hg^(0)emission.