This study addresses the pressing need for energy-efficient greenhouse management by focusing on the innovative application of natural ventilation.The primary objective of this study is to evaluate various ventilation...This study addresses the pressing need for energy-efficient greenhouse management by focusing on the innovative application of natural ventilation.The primary objective of this study is to evaluate various ventilation strategies to enhance energy efficiency and optimize crop production in agricultural greenhouses.Employing advanced numerical simulation tools,the study conducts a comprehensive assessment of natural ventilation’s effectiveness under real-world conditions.The results underscore the crucial role of the stack effect and strategic window positioning in greenhouse cooling,providing valuable insights for greenhouse designers.Our findings shed light on the significant benefits of optimized ventilation and also offer practical implications for improving greenhouse design,ensuring sustainable and efficient agricultural practices.The study demonstrated energy savings in cooling from November to April,with a maximum saving of 680 kWh in March,indicating the effectiveness of strategically positioning windows to leverage the stack effect.This approach enhances plant growth and reduces the need for costly cooling systems,thereby improving overall energy efficiency and lowering operational expenses.展开更多
The perfect combination of renewable energy and desalination technologies is the key to meeting water demands in a cost-effective,efficient and environmentally friendly way.The desalination technique by humidification...The perfect combination of renewable energy and desalination technologies is the key to meeting water demands in a cost-effective,efficient and environmentally friendly way.The desalination technique by humidificationdehumidification is non-conventional approach suitable for areas with low infrastructure(such as rural and decentralized regions)since it does not require permanent maintenance.In this study,this technology is implemented by using solar energy as a source of thermal power.A seawater desalination unit is considered,which consists of a chamber with two evaporators(humidifiers),a wetted porous material made of a corrugated cellulose cardboard and a condenser(dehumidifier).The evaporation system is tested with dry bulb temperature and relative air humidity data.The results of numerical simulations indicate that higher inlet air velocities(from 0.75 to 3 m/s)lead to a decrease in theΔT,ΔRH,and effectiveness.With the air remaining within the evaporator for 30 cm,the temperature differential increases to 5.7°C,accompanied by a 39%rise in relative humidity contrast.These changes result in a significant enhancement in humidification efficiency,achieving a remarkable efficiency level of 78%.However,a wettability value of 630 m^(2)/m^(3)leads to a smaller reduction of these parameters.Increasing the pad thickness,particularly to 0.3 m,improves performance by boostingΔT,ΔRH,and effectiveness,especially for pads with a wettability of 630 m^(2)/m^(3),for which superior performances are predicted by the numerical tests.展开更多
The interaction between metabolic dysfunction and inflammation is central to the development of neurodegenerative diseases such as Alzheimer’s disease and Parkinson’s disease.Obesity-related conditions like type 2 d...The interaction between metabolic dysfunction and inflammation is central to the development of neurodegenerative diseases such as Alzheimer’s disease and Parkinson’s disease.Obesity-related conditions like type 2 diabetes and non-alcoholic fatty liver disease exacerbate this relationship.Peripheral lipid accumulation,particularly in the liver,initiates a cascade of inflammatory processes that extend to the brain,influencing critical metabolic regulatory regions.Ceramide and palmitate,key lipid components,along with lipid transporters lipocalin-2 and apolipoprotein E,contribute to neuroinflammation by disrupting blood–brain barrier integrity and promoting gliosis.Peripheral insulin resistance further exacerbates brain insulin resistance and neuroinflammation.Preclinical interventions targeting peripheral lipid metabolism and insulin signaling pathways have shown promise in reducing neuroinflammation in animal models.However,translating these findings to clinical practice requires further investigation into human subjects.In conclusion,metabolic dysfunction,peripheral inflammation,and insulin resistance are integral to neuroinflammation and neurodegeneration.Understanding these complex mechanisms holds potential for identifying novel therapeutic targets and improving outcomes for neurodegenerative diseases.展开更多
Background: Malaria and typhoid have remained major infectious tropical diseases. Clinically, whenever there is severe malaria, cough is always an associating symptom owing to typhoid infection arising from poor hygie...Background: Malaria and typhoid have remained major infectious tropical diseases. Clinically, whenever there is severe malaria, cough is always an associating symptom owing to typhoid infection arising from poor hygiene in respect to drinking water and food. There is a strong association between human blood group and disease. Residual malaria transmission, effect of climate change on malaria vector composition, environmental management targeted at malaria breeding control as an intervention strategy are areas of interest to WHO in malaria control in Sub-saharan Africa. A body of data is been built on susceptibility of human blood groups to malaria, HIV and HBV and presently malaria and typhoid. If climate change warrants a change in composition of vectors and as well resistance to ACT therapy, the susceptibility or vulnerability of the human blood group is also called to question. The link between susceptibility of human blood group to malaria and typhoid has not been previously investigated. Purpose: The present study assesses the genetic disposition (susceptibility of human blood groups and abo analysis) to malaria and typhoid infections. Patients and Methods: One hundred (100) patients were screened for malaria and typhoid infections in a tertiary health facility—His glory hospital Lagos, Nigeria. Blood samples were collected by venu-puncture from 53 females and 47 males adults aged between 15 – 47 years, who were infected either singly or coinfected with malaria and typhoid. Microscopic detection of P. falciparum, widal serological technique for salmonella antibody presence and genotypic determination were all done using standard WHO methods. Human material or data were analyzed or performed in accordance with the declaration of Helsinki (2000). Ethical clearance was obtained from the ethic and research committee of the Ministry of Health via the Faculty of the Basic Medical Sciences, University of Calabar (Ethical Certificate number CRS/MOH/HRP/2023/396). Results: The results obtained expressed in percentage frequency show that genotype AA were more susceptible to typhoid and malaria infections compared to AS and SS, also blood group O was more susceptible to malaria and typhoid infection compared to blood groups A, AB and B, although, there is no significant difference between male and female gender, susceptibility to malaria infection, the female gender is more susceptible to typhoid than the male. The finding may be relevant to malaria susceptibility and genetics and thus provide baseline information on management of the scourge. Conclusion: We conclude that genotype AA and blood group 0+ are more susceptible to malaria and typhoid infection in humans.展开更多
This work details the development of a broad-spectrum LNA (Low Noise Amplifier) circuit using a 65 nm CMOS technology. The design incorporates an inductive degeneracy circuit, employing a theoretical approach to enhan...This work details the development of a broad-spectrum LNA (Low Noise Amplifier) circuit using a 65 nm CMOS technology. The design incorporates an inductive degeneracy circuit, employing a theoretical approach to enhance gain, minimize noise levels, and uphold low power consumption. The progression includes a shift to a cascode structure to further refine LNA parameters. Ultimately, with a 1.8 V bias, the achieved performance showcases a gain-to-noise figure ratio of 16 dB/0.5 dB, an IIP3 linearity at 5.1 dBm, and a power consumption of 3 mW. This architecture is adept at operating across a wide frequency band spanning from 0.5 GHz to 6 GHz, rendering it applicable in diverse RF scenarios.展开更多
BACKGROUND Vaccine hesitancy is a major challenge in the fight against the coronavirus disease 2019(COVID-19)pandemic.Identifying the sociodemographic factors associated with vaccine acceptance among Nigerians is cruc...BACKGROUND Vaccine hesitancy is a major challenge in the fight against the coronavirus disease 2019(COVID-19)pandemic.Identifying the sociodemographic factors associated with vaccine acceptance among Nigerians is crucial for improving vaccine uptake.AIM To assess the acceptance rate of COVID-19 vaccine and its related determinants among Nigerians.METHODS An online cross-sectional survey(observational study)was conducted between February 2021 and May 2021,using a questionnaire hosted on SurveyMonkey.The invitation to take part in the poll was sent out to participants through social networking platforms.A logistic regression was used to determine which sociodemographic factors were associated with vaccine acceptance constructs.RESULTS A total of 1800 persons responded to the survey,a larger proportion of whom were males(53.9%)and within the age group of 21-30 years(29.4%)and earned an average income of less than$500 per month(43.3%).Only 0.56%of participants had a high perceived risk of COVID-19 infection,while only 1.11%had a perceived risk of dying from COVID-19.The perception rate of the COVID-19 vaccine among participants was 51.1%,while the acceptance rate was 63.9%.There was no significant association between the COVID-19 vaccine acceptance rate and related determinants assessed,particularly age(χ²=3.049,P=0.550),sex(χ²=0.102,P=0.749),average income(χ²=3.802,P=0.875),and religion(χ²=2.819,P=0.420).Participants with chronic conditions demonstrated a higher acceptance rate compared to the general population.CONCLUSION Despite the positive perception observed and substantial vaccine acceptance rate among the study participants,more public health interventions are still needed to enhance vaccine acceptability in Nigeria.展开更多
It is essential to study the porosity,thermal conductivity,and P-wave velocity of calcarenites,as well as the anisotropy coefficients of the thermal conductivity and P-wave velocity,for civil engineering,and conservat...It is essential to study the porosity,thermal conductivity,and P-wave velocity of calcarenites,as well as the anisotropy coefficients of the thermal conductivity and P-wave velocity,for civil engineering,and conservation and restoration of historical monuments.This study focuses on measuring the thermal conductivity using the thermal conductivity scanning(TCS)technique and measuring the P-wave ve-locity using portable equipment.This was applied for some dry and saturated calcarenite samples in the horizontal and vertical directions(parallel and perpendicular to the bedding plane,respectively).The calcarenites were selected from some historical monuments in Morocco.These physical properties were measured in the laboratory to find a reliable relationship between all of these properties.As a result of the statistical analysis of the obtained data,excellent linear relationships were observed between the porosity and both the thermal conductivity and porosity.These relationships are characterized by relatively high coefficients of determination for the horizontal and vertical samples.Based on the thermal conductivity and P-wave velocity values in these two directions,the anisotropy coefficients of these two properties were calculated.The internal structure and the pore fabric of the calcarenite samples were delineated using scanning electron microscopy(SEM),while their chemical and mineral compositions were studied using the energy dispersive X-ray analysis(EDXA)and X-ray diffraction(XRD)techniques.展开更多
In the present work,we have employed machine learning(ML)techniques to evaluate ductile-brittle(DB)behaviors in intermetallic compounds(IMCs)which can form magnesium(Mg)alloys.This procedure was mainly conducted by a ...In the present work,we have employed machine learning(ML)techniques to evaluate ductile-brittle(DB)behaviors in intermetallic compounds(IMCs)which can form magnesium(Mg)alloys.This procedure was mainly conducted by a proxy-based method,where the ratio of shear(G)/bulk(B)moduli was used as a proxy to identify whether the compound is ductile or brittle.Starting from compounds information(composition and crystal structure)and their moduli,as found in open databases(AFLOW),ML-based models were built,and those models were used to predict the moduli in other compounds,and accordingly,to foresee the ductile-brittle behaviors of these new compounds.The results reached in the present work showed that the built models can effectively catch the elastic moduli of new compounds.This was confirmed through moduli calculations done by density functional theory(DFT)on some compounds,where the DFT calculations were consistent with the ML prediction.A further confirmation on the reliability of the built ML models was considered through relating between the DB behavior in MgBe_(13) and MgPd_(2),as evaluated by the ML-predicted moduli,and the nature of chemical bonding in these two compounds,which in turn,was investigated by the charge density distribution(CDD)and electron localization function(ELF)obtained by DFT methodology.The ML-evaluated DB behaviors of the two compounds was also consistent with the DFT calculations of CDD and ELF.These findings and confirmations gave legitimacy to the built model to be employed in further prediction processes.Indeed,as examples,the DB characteristics were investigated in IMCs that might from in three Mg alloy series,involving AZ,ZX and WE.展开更多
The heat and mass transfer of two immiscible fluids in an inclined channel with thermal diffusion,vicious,and Darcy dissipation is studied.The first region consists of a clear fluid,and the second one is filled with a...The heat and mass transfer of two immiscible fluids in an inclined channel with thermal diffusion,vicious,and Darcy dissipation is studied.The first region consists of a clear fluid,and the second one is filled with a nanofluid saturated with a porous medium.The behaviors of Cu-H_(2)O,In-H_(2)O,and Au-H_(2)O nanofluids are analyzed.The transport properties are assumed to be constant.The coupled non-linear equations of the flow model are transformed into the dimensionless form,and the solutions for the velocity,temperature,and concentration are obtained by the regular perturbation technique.Investigations are carried out on the flow characteristics for various values of the material parameters.The results show that the velocity and temperature of the fluids enhance with the thermal Grashof number,solutal Grashof number,and Brinkman number while decrease with the porosity parameter and solid volume fraction.展开更多
Gamma-aminobutyric acid(GABA)is a ubiquitous four-carbon non-protein amino acid that is involved in various physiological processes of plant growth and development,such as root architecture,stem elongation,leaf senesc...Gamma-aminobutyric acid(GABA)is a ubiquitous four-carbon non-protein amino acid that is involved in various physiological processes of plant growth and development,such as root architecture,stem elongation,leaf senescence,pollen tube growth,fruit ripening,and seed germination.GABA is also related to plant stress responses,such as drought,salt,cold,and heat stresses.Regulation of GABA in plant stress responses is complex and involves multiple signaling pathways,including calcium and hormone signaling.This paper systematically reviews the synthesis,metabolic pathways and regulatory role of GABA in plants,which will provide new insights into the understanding of plant growth and stress responses and offer novel strategies for improving crop productivity and stress.展开更多
Cancer is considered one of the most lethal diseases responsible for causing deaths worldwide.Although there have been many breakthroughs in anticancer development,cancer remains the major cause of death globally.In t...Cancer is considered one of the most lethal diseases responsible for causing deaths worldwide.Although there have been many breakthroughs in anticancer development,cancer remains the major cause of death globally.In this regard,targeting cancer-causing enzymes is one of the efficient therapeutic strategies.Biological functions like cell cycle,transcription,metabolism,apoptosis,and other depend primarily on cyclin-dependent kinases(CDKs).These enzymes help in the replication of DNA in the normal cell cycle process,and deregulation in the functioning of any CDK can cause abnormal cell growth,which leads to cancer.This review is focused on anticancer drug discovery against cell cycle CDK enzyme using an in silico technique,i.e.,molecular docking studies.Molecular docking helps in deciphering the key interactions formed within the inhibitor and the respective enzyme.This concise study provides an overview of the most current in silico research advancements made in the field of anticancer drug discovery.The findings presented in the current review article can help in understanding the nature of inhibitor-target interactions and provide information on the structural and molecular prerequisites for the inhibition of cell cycle CDKs.展开更多
This study was carried out to determine the prevalence of HIV-1 and -2 among three selected secondary schools in Udenu Local Government Area of Enugu State, Nigeria. Three hundred students were recruited for this stud...This study was carried out to determine the prevalence of HIV-1 and -2 among three selected secondary schools in Udenu Local Government Area of Enugu State, Nigeria. Three hundred students were recruited for this study representing 120 males (40%) and 180 females (60%) with their age ranging from 12 to 20 years from September to November, 2010. Samples of blood were collected and processed using standard laboratory procedures. All the students were screened for the presence of antibodies to HIV-1 and -2 using 2 enzyme-linked immunosorbent assay (ELISA) rapid screening kits, based on WHO systems-2 for detecting antibodies to HIV-1 and -2. The diagnosis of HIV infection was further confirmed by Western blot. The results showed that out of the 300 students who were enrolled into the study, 6 (2%) were positive for HIV-1 and -2 antibodies including two males (0.7%) and four females (1.3%). Statistically, there is a significant difference in the distribution of HIV infections by gender (P 0.05). Although its prevalence is low, the presence of HIV-1 and -2 antibodies in Secondary School students of Udenu L.G.A. of Enugu State should be worrisome because it can easily be transmitted to other healthy individuals in the nearest future. Therefore, this calls for a concerted and synergistic effort to nip the spread in the bud so that it cannot spread to other teenagers and the larger community.展开更多
Differential equation has widely applied in science and engineering calculation. Runge Kutta method is a main method for solving differential equations. In this paper, the numerical properties of Runge-Kutta methods f...Differential equation has widely applied in science and engineering calculation. Runge Kutta method is a main method for solving differential equations. In this paper, the numerical properties of Runge-Kutta methods for the equation u′(t) = au(t)+bu([K/N* t]) is dealed with, where K and N is relatively prime and K < N,K,N∈ Z+. The conditions are obtained under which the numerical solutions preserve the analytical stability properties of the analytic ones and some numerical experiments are given.展开更多
Under consideration in this study is the discrete coupled modified Korteweg-de Vries(mKdV)equation with 4×4 Lax pair.Firstly,through using continuous limit technique,this discrete equation can be mapped to the co...Under consideration in this study is the discrete coupled modified Korteweg-de Vries(mKdV)equation with 4×4 Lax pair.Firstly,through using continuous limit technique,this discrete equation can be mapped to the coupled KdV and mKdV equations,which may depict the development of shallow water waves,the optical soliton propagation in cubic nonlinear media and the Alfven wave in a cold collision-free plasma.Secondly,the discrete generalized(r,N-r)-fold Darboux transformation is constructed and extended to solve this discrete coupled equation with the fourth-order linear spectral problem,from which diverse exact solutions including usual multi-soliton and semi-rational soliton solutions on the vanishing background,higher-order rational soliton and mixed hyperbolic-rational soliton solutions on the non-vanishing background are derived,and the limit states of some soliton and rational soliton solutions are analyzed by the asymptotic analysis technique.Finally,the numerical simulations are used to explore the dynamical behaviors of some exact soliton solutions.These results may be helpful for understanding some physical phenomena in fields of shallow water wave,optics,and plasma physics.展开更多
Studying the dynamic changes in the coastline of the northeastern Caspian Sea is significant since the level of the Caspian is unstable,and the coastline change can cause enormous damage to the ecology,economy,and pop...Studying the dynamic changes in the coastline of the northeastern Caspian Sea is significant since the level of the Caspian is unstable,and the coastline change can cause enormous damage to the ecology,economy,and population of the coastal part of Kazakhstan.In this work,we use remote sensing and Geographic Information System(GIS)technologies to study the changes in the coastline of the northeastern Caspian Sea and predict the extent of flooding with increasing water levels.The proposed methodology for creating dynamic maps can be used to monitor the coastline and forecast the extent of flooding in the area.As a result of this work,the main factors affecting changes in the coastline were identified.After analyzing the water level data from 1988 to 2019,it was revealed that the rise in water level was observed from 1980 to 1995.The maximum sea level rise was recorded at-26.04 m.After that,the sea level began to fall,and between 1996 and 2009,there were no significant changes;the water level fluctuated with an average of-27.18 m.Then,a map of the water level dynamics in the Caspian Sea from 1988 to 2019 was compiled.According to the dynamics map,water level rise and significant coastal retreat were revealed,especially in the northern part of the Caspian Sea and the northern and southern parts of Sora Kaydak.The method for predicting the estimated flooding area was described.As a result,based on a single map,the flooding area of the northeast coast was predicted.A comparative analysis of Landsat and SRTM data is presented.展开更多
Renewable energy has garnered attention due to the need for sustainable energy sources.Wind power has emerged as an alternative that has contributed to the transition towards cleaner energy.As the importance of wind e...Renewable energy has garnered attention due to the need for sustainable energy sources.Wind power has emerged as an alternative that has contributed to the transition towards cleaner energy.As the importance of wind energy grows,it can be crucial to provide forecasts that optimize its performance potential.Artificial intelligence(AI)methods have risen in prominence due to how well they can handle complicated systems while enhancing the accuracy of prediction.This study explored the area of AI to predict wind-energy production at a wind farm in Yalova,Turkey,using four different AI approaches:support vector machines(SVMs),decision trees,adaptive neuro-fuzzy inference systems(ANFIS)and artificial neural networks(ANNs).Wind speed and direction were considered as essential input parameters,with wind energy as the target parameter,and models are thoroughly evaluated using metrics such as the mean absolute percentage error(MAPE),coefficient of determination(R~2),and mean absolute error(MAE).The findings accentuate the superior performance of the SVM,which delivered the lowest MAPE(2.42%),the highest R~2(0.95),and the lowest MAE(71.21%)compared with actual values,while ANFIS was less effective in this context.The main aim of this comparative analysis was to rank the models to move to the next step in improving the least efficient methods by combining them with optimization algorithms,such as metaheuristic algorithms.展开更多
We demonstrate a simple method to measure electric field intensity by using doublet electromagnetically induced transparency(EIT) spectra of cold Rb Rydberg atoms, where the frequency of the coupling laser does not ne...We demonstrate a simple method to measure electric field intensity by using doublet electromagnetically induced transparency(EIT) spectra of cold Rb Rydberg atoms, where the frequency of the coupling laser does not need to be locked. Based on the Stark splitting of the Rb Rydberg state, 10D_(3/2), under electric fields and the corresponding calculated polarizabilities, the real electric field intensity is calculated using the difference in radio-frequency diffraction between two acousto-optic modulators, which acts as a frequency criterion that allows us to measure the electrical field without locking the coupling laser. The value measured by this simple method shows a good agreement with our previous work [Opt.Express 29 1558(2021)] where the frequency of the coupling laser needs to be locked with an additional EIT spectrum based on atom vapor and a proportional–integral–differential feedback circuit. Our presented method can also be extended to the measurement of electric field based on hot Rydberg atom vapor, which has application in industry.展开更多
Mobile Ad hoc Network(MANET)is decentralized wireless network and can communicate without existing infrastructure in many areas.MANET is vulnerable to various attacks that affect its performance such as blackhole atta...Mobile Ad hoc Network(MANET)is decentralized wireless network and can communicate without existing infrastructure in many areas.MANET is vulnerable to various attacks that affect its performance such as blackhole attack.Blackhole attacker,inject fault routing information to persuade the source node to select the path with malicious node as the shortest path.To eliminate malicious nodes from launching any collaborative attack.A cooperative Trapping Approach(CTA)was proposed based on modifying Ad-hoc On-demand Distance Vector(AODV)routing protocol and trapping the malicious nodes by responding to the trap request message.The approach aims to eliminate and rule out both single and collaborative malicious blackhole nodes from any attack.The approach realizes a backward tracking mechanism to perform the elimination process.The proposed algorithm(CTA)was executed using NS-2 network simulator.The performance metrics that has been considered to evaluate the performance of the proposed algorithm such as throughput,end to end delay,packet delivery ratio,and consuming energy.The experimental results have shown the performance metrics of the proposed approach outperformed other state of at algorithms.展开更多
In this work,we present a model that uses the fractional order Caputo derivative for the novel Coronavirus disease 2019(COVID-19)with different hospitalization strategies for severe and mild cases and incorporate an a...In this work,we present a model that uses the fractional order Caputo derivative for the novel Coronavirus disease 2019(COVID-19)with different hospitalization strategies for severe and mild cases and incorporate an awareness program.We generalize the SEIR model of the spread of COVID-19 with a private focus on the transmissibility of people who are aware of the disease and follow preventative health measures and people who are ignorant of the disease and do not follow preventive health measures.Moreover,individuals with severe,mild symptoms and asymptomatically infected are also considered.The basic reproduction number(R0)and local stability of the disease-free equilibrium(DFE)in terms of R0 are investigated.Also,the uniqueness and existence of the solution are studied.Numerical simulations are performed by using some real values of parameters.Furthermore,the immunization of a sample of aware susceptible individuals in the proposed model to forecast the effect of the vaccination is also considered.Also,an investigation of the effect of public awareness on transmission dynamics is one of our aim in this work.Finally,a prediction about the evolution of COVID-19 in 1000 days is given.For the qualitative theory of the existence of a solution,we use some tools of nonlinear analysis,including Lipschitz criteria.Also,for the numerical interpretation,we use the Adams-Moulton-Bashforth procedure.All the numerical results are presented graphically.展开更多
Elucidation of a reaction mechanism is the most critical aspect for designing electrodes for highperformance secondary batteries.Herein,we investigate the sodium insertion/extraction into an iron fluoride hydrate(FeF_...Elucidation of a reaction mechanism is the most critical aspect for designing electrodes for highperformance secondary batteries.Herein,we investigate the sodium insertion/extraction into an iron fluoride hydrate(FeF_(3)·0.5H_(2)O)electrode for sodium-ion batteries(SIBs).The electrode material is prepared by employing an ionic liquid 1-butyl-3-methylimidazolium-tetrafluoroborate,which serves as a reaction medium and precursor for F^(-)ions.The crystal structure of FeF_(3)·0.5H_(2)O is observed as pyrochlore type with large open 3-D tunnels and a unit cell volume of 1129A^(3).The morphology of FeF_(3)·0.5H_(2)O is spherical shape with a mesoporous structure.The microstructure analysis reveals primary particle size of around 10 nm.The FeF_(3)·0.5H_(2)O cathode exhibits stable discharge capacities of 158,210,and 284 mA h g^(-1) in three different potential ranges of 1.5-4.5,1.2-4.5,and 1.0-4.5 V,respectively at 0.05 C rate.The specific capacities remained stable in over 50 cycles in all three potential ranges,while the rate capability was best in the potential range of 1.5-4.5 V.The electrochemical sodium storage mechanism is studied using X-ray absorption spectroscopy,indicating higher conversion at a more discharged state.Ex-situ M?ssbauer spectroscopy strengthens the results for reversible reduction/oxidation of Fe.These results will be favorable to establish high-performance cathode materials with selective voltage window for SIBs.展开更多
文摘This study addresses the pressing need for energy-efficient greenhouse management by focusing on the innovative application of natural ventilation.The primary objective of this study is to evaluate various ventilation strategies to enhance energy efficiency and optimize crop production in agricultural greenhouses.Employing advanced numerical simulation tools,the study conducts a comprehensive assessment of natural ventilation’s effectiveness under real-world conditions.The results underscore the crucial role of the stack effect and strategic window positioning in greenhouse cooling,providing valuable insights for greenhouse designers.Our findings shed light on the significant benefits of optimized ventilation and also offer practical implications for improving greenhouse design,ensuring sustainable and efficient agricultural practices.The study demonstrated energy savings in cooling from November to April,with a maximum saving of 680 kWh in March,indicating the effectiveness of strategically positioning windows to leverage the stack effect.This approach enhances plant growth and reduces the need for costly cooling systems,thereby improving overall energy efficiency and lowering operational expenses.
文摘The perfect combination of renewable energy and desalination technologies is the key to meeting water demands in a cost-effective,efficient and environmentally friendly way.The desalination technique by humidificationdehumidification is non-conventional approach suitable for areas with low infrastructure(such as rural and decentralized regions)since it does not require permanent maintenance.In this study,this technology is implemented by using solar energy as a source of thermal power.A seawater desalination unit is considered,which consists of a chamber with two evaporators(humidifiers),a wetted porous material made of a corrugated cellulose cardboard and a condenser(dehumidifier).The evaporation system is tested with dry bulb temperature and relative air humidity data.The results of numerical simulations indicate that higher inlet air velocities(from 0.75 to 3 m/s)lead to a decrease in theΔT,ΔRH,and effectiveness.With the air remaining within the evaporator for 30 cm,the temperature differential increases to 5.7°C,accompanied by a 39%rise in relative humidity contrast.These changes result in a significant enhancement in humidification efficiency,achieving a remarkable efficiency level of 78%.However,a wettability value of 630 m^(2)/m^(3)leads to a smaller reduction of these parameters.Increasing the pad thickness,particularly to 0.3 m,improves performance by boostingΔT,ΔRH,and effectiveness,especially for pads with a wettability of 630 m^(2)/m^(3),for which superior performances are predicted by the numerical tests.
基金supported by a Presidential Postdoctoral Fellowship (021229-00001) from Nanyang Technological University,Singapore (to JZ)a Lee Kong Chian School of Medicine Dean’s Postdoctoral Fellowship (021207-00001) from NTU Singaporea Mistletoe Research Fellowship (022522-00001) from the Momental Foundaton,USA (to CHL)
文摘The interaction between metabolic dysfunction and inflammation is central to the development of neurodegenerative diseases such as Alzheimer’s disease and Parkinson’s disease.Obesity-related conditions like type 2 diabetes and non-alcoholic fatty liver disease exacerbate this relationship.Peripheral lipid accumulation,particularly in the liver,initiates a cascade of inflammatory processes that extend to the brain,influencing critical metabolic regulatory regions.Ceramide and palmitate,key lipid components,along with lipid transporters lipocalin-2 and apolipoprotein E,contribute to neuroinflammation by disrupting blood–brain barrier integrity and promoting gliosis.Peripheral insulin resistance further exacerbates brain insulin resistance and neuroinflammation.Preclinical interventions targeting peripheral lipid metabolism and insulin signaling pathways have shown promise in reducing neuroinflammation in animal models.However,translating these findings to clinical practice requires further investigation into human subjects.In conclusion,metabolic dysfunction,peripheral inflammation,and insulin resistance are integral to neuroinflammation and neurodegeneration.Understanding these complex mechanisms holds potential for identifying novel therapeutic targets and improving outcomes for neurodegenerative diseases.
文摘Background: Malaria and typhoid have remained major infectious tropical diseases. Clinically, whenever there is severe malaria, cough is always an associating symptom owing to typhoid infection arising from poor hygiene in respect to drinking water and food. There is a strong association between human blood group and disease. Residual malaria transmission, effect of climate change on malaria vector composition, environmental management targeted at malaria breeding control as an intervention strategy are areas of interest to WHO in malaria control in Sub-saharan Africa. A body of data is been built on susceptibility of human blood groups to malaria, HIV and HBV and presently malaria and typhoid. If climate change warrants a change in composition of vectors and as well resistance to ACT therapy, the susceptibility or vulnerability of the human blood group is also called to question. The link between susceptibility of human blood group to malaria and typhoid has not been previously investigated. Purpose: The present study assesses the genetic disposition (susceptibility of human blood groups and abo analysis) to malaria and typhoid infections. Patients and Methods: One hundred (100) patients were screened for malaria and typhoid infections in a tertiary health facility—His glory hospital Lagos, Nigeria. Blood samples were collected by venu-puncture from 53 females and 47 males adults aged between 15 – 47 years, who were infected either singly or coinfected with malaria and typhoid. Microscopic detection of P. falciparum, widal serological technique for salmonella antibody presence and genotypic determination were all done using standard WHO methods. Human material or data were analyzed or performed in accordance with the declaration of Helsinki (2000). Ethical clearance was obtained from the ethic and research committee of the Ministry of Health via the Faculty of the Basic Medical Sciences, University of Calabar (Ethical Certificate number CRS/MOH/HRP/2023/396). Results: The results obtained expressed in percentage frequency show that genotype AA were more susceptible to typhoid and malaria infections compared to AS and SS, also blood group O was more susceptible to malaria and typhoid infection compared to blood groups A, AB and B, although, there is no significant difference between male and female gender, susceptibility to malaria infection, the female gender is more susceptible to typhoid than the male. The finding may be relevant to malaria susceptibility and genetics and thus provide baseline information on management of the scourge. Conclusion: We conclude that genotype AA and blood group 0+ are more susceptible to malaria and typhoid infection in humans.
文摘This work details the development of a broad-spectrum LNA (Low Noise Amplifier) circuit using a 65 nm CMOS technology. The design incorporates an inductive degeneracy circuit, employing a theoretical approach to enhance gain, minimize noise levels, and uphold low power consumption. The progression includes a shift to a cascode structure to further refine LNA parameters. Ultimately, with a 1.8 V bias, the achieved performance showcases a gain-to-noise figure ratio of 16 dB/0.5 dB, an IIP3 linearity at 5.1 dBm, and a power consumption of 3 mW. This architecture is adept at operating across a wide frequency band spanning from 0.5 GHz to 6 GHz, rendering it applicable in diverse RF scenarios.
文摘BACKGROUND Vaccine hesitancy is a major challenge in the fight against the coronavirus disease 2019(COVID-19)pandemic.Identifying the sociodemographic factors associated with vaccine acceptance among Nigerians is crucial for improving vaccine uptake.AIM To assess the acceptance rate of COVID-19 vaccine and its related determinants among Nigerians.METHODS An online cross-sectional survey(observational study)was conducted between February 2021 and May 2021,using a questionnaire hosted on SurveyMonkey.The invitation to take part in the poll was sent out to participants through social networking platforms.A logistic regression was used to determine which sociodemographic factors were associated with vaccine acceptance constructs.RESULTS A total of 1800 persons responded to the survey,a larger proportion of whom were males(53.9%)and within the age group of 21-30 years(29.4%)and earned an average income of less than$500 per month(43.3%).Only 0.56%of participants had a high perceived risk of COVID-19 infection,while only 1.11%had a perceived risk of dying from COVID-19.The perception rate of the COVID-19 vaccine among participants was 51.1%,while the acceptance rate was 63.9%.There was no significant association between the COVID-19 vaccine acceptance rate and related determinants assessed,particularly age(χ²=3.049,P=0.550),sex(χ²=0.102,P=0.749),average income(χ²=3.802,P=0.875),and religion(χ²=2.819,P=0.420).Participants with chronic conditions demonstrated a higher acceptance rate compared to the general population.CONCLUSION Despite the positive perception observed and substantial vaccine acceptance rate among the study participants,more public health interventions are still needed to enhance vaccine acceptability in Nigeria.
文摘It is essential to study the porosity,thermal conductivity,and P-wave velocity of calcarenites,as well as the anisotropy coefficients of the thermal conductivity and P-wave velocity,for civil engineering,and conservation and restoration of historical monuments.This study focuses on measuring the thermal conductivity using the thermal conductivity scanning(TCS)technique and measuring the P-wave ve-locity using portable equipment.This was applied for some dry and saturated calcarenite samples in the horizontal and vertical directions(parallel and perpendicular to the bedding plane,respectively).The calcarenites were selected from some historical monuments in Morocco.These physical properties were measured in the laboratory to find a reliable relationship between all of these properties.As a result of the statistical analysis of the obtained data,excellent linear relationships were observed between the porosity and both the thermal conductivity and porosity.These relationships are characterized by relatively high coefficients of determination for the horizontal and vertical samples.Based on the thermal conductivity and P-wave velocity values in these two directions,the anisotropy coefficients of these two properties were calculated.The internal structure and the pore fabric of the calcarenite samples were delineated using scanning electron microscopy(SEM),while their chemical and mineral compositions were studied using the energy dispersive X-ray analysis(EDXA)and X-ray diffraction(XRD)techniques.
基金supported by National Research Foundation(NRF)of South Korea(2020R1A2C1004720)。
文摘In the present work,we have employed machine learning(ML)techniques to evaluate ductile-brittle(DB)behaviors in intermetallic compounds(IMCs)which can form magnesium(Mg)alloys.This procedure was mainly conducted by a proxy-based method,where the ratio of shear(G)/bulk(B)moduli was used as a proxy to identify whether the compound is ductile or brittle.Starting from compounds information(composition and crystal structure)and their moduli,as found in open databases(AFLOW),ML-based models were built,and those models were used to predict the moduli in other compounds,and accordingly,to foresee the ductile-brittle behaviors of these new compounds.The results reached in the present work showed that the built models can effectively catch the elastic moduli of new compounds.This was confirmed through moduli calculations done by density functional theory(DFT)on some compounds,where the DFT calculations were consistent with the ML prediction.A further confirmation on the reliability of the built ML models was considered through relating between the DB behavior in MgBe_(13) and MgPd_(2),as evaluated by the ML-predicted moduli,and the nature of chemical bonding in these two compounds,which in turn,was investigated by the charge density distribution(CDD)and electron localization function(ELF)obtained by DFT methodology.The ML-evaluated DB behaviors of the two compounds was also consistent with the DFT calculations of CDD and ELF.These findings and confirmations gave legitimacy to the built model to be employed in further prediction processes.Indeed,as examples,the DB characteristics were investigated in IMCs that might from in three Mg alloy series,involving AZ,ZX and WE.
基金supported by the research seed grant(No.RU:EST:MT:2022/4)funded by REVA University.
文摘The heat and mass transfer of two immiscible fluids in an inclined channel with thermal diffusion,vicious,and Darcy dissipation is studied.The first region consists of a clear fluid,and the second one is filled with a nanofluid saturated with a porous medium.The behaviors of Cu-H_(2)O,In-H_(2)O,and Au-H_(2)O nanofluids are analyzed.The transport properties are assumed to be constant.The coupled non-linear equations of the flow model are transformed into the dimensionless form,and the solutions for the velocity,temperature,and concentration are obtained by the regular perturbation technique.Investigations are carried out on the flow characteristics for various values of the material parameters.The results show that the velocity and temperature of the fluids enhance with the thermal Grashof number,solutal Grashof number,and Brinkman number while decrease with the porosity parameter and solid volume fraction.
基金supported by Start-Up Funding from Shanghai University and the National Natural Science Foundation of China(Grant No.31970289).
文摘Gamma-aminobutyric acid(GABA)is a ubiquitous four-carbon non-protein amino acid that is involved in various physiological processes of plant growth and development,such as root architecture,stem elongation,leaf senescence,pollen tube growth,fruit ripening,and seed germination.GABA is also related to plant stress responses,such as drought,salt,cold,and heat stresses.Regulation of GABA in plant stress responses is complex and involves multiple signaling pathways,including calcium and hormone signaling.This paper systematically reviews the synthesis,metabolic pathways and regulatory role of GABA in plants,which will provide new insights into the understanding of plant growth and stress responses and offer novel strategies for improving crop productivity and stress.
文摘Cancer is considered one of the most lethal diseases responsible for causing deaths worldwide.Although there have been many breakthroughs in anticancer development,cancer remains the major cause of death globally.In this regard,targeting cancer-causing enzymes is one of the efficient therapeutic strategies.Biological functions like cell cycle,transcription,metabolism,apoptosis,and other depend primarily on cyclin-dependent kinases(CDKs).These enzymes help in the replication of DNA in the normal cell cycle process,and deregulation in the functioning of any CDK can cause abnormal cell growth,which leads to cancer.This review is focused on anticancer drug discovery against cell cycle CDK enzyme using an in silico technique,i.e.,molecular docking studies.Molecular docking helps in deciphering the key interactions formed within the inhibitor and the respective enzyme.This concise study provides an overview of the most current in silico research advancements made in the field of anticancer drug discovery.The findings presented in the current review article can help in understanding the nature of inhibitor-target interactions and provide information on the structural and molecular prerequisites for the inhibition of cell cycle CDKs.
文摘This study was carried out to determine the prevalence of HIV-1 and -2 among three selected secondary schools in Udenu Local Government Area of Enugu State, Nigeria. Three hundred students were recruited for this study representing 120 males (40%) and 180 females (60%) with their age ranging from 12 to 20 years from September to November, 2010. Samples of blood were collected and processed using standard laboratory procedures. All the students were screened for the presence of antibodies to HIV-1 and -2 using 2 enzyme-linked immunosorbent assay (ELISA) rapid screening kits, based on WHO systems-2 for detecting antibodies to HIV-1 and -2. The diagnosis of HIV infection was further confirmed by Western blot. The results showed that out of the 300 students who were enrolled into the study, 6 (2%) were positive for HIV-1 and -2 antibodies including two males (0.7%) and four females (1.3%). Statistically, there is a significant difference in the distribution of HIV infections by gender (P 0.05). Although its prevalence is low, the presence of HIV-1 and -2 antibodies in Secondary School students of Udenu L.G.A. of Enugu State should be worrisome because it can easily be transmitted to other healthy individuals in the nearest future. Therefore, this calls for a concerted and synergistic effort to nip the spread in the bud so that it cannot spread to other teenagers and the larger community.
基金This work is supported by the Research Fund of the Natural Science Foundation of Heilongjiang Province (No. A201214) and the National Natural Science Foundation of China(61501148).
文摘Differential equation has widely applied in science and engineering calculation. Runge Kutta method is a main method for solving differential equations. In this paper, the numerical properties of Runge-Kutta methods for the equation u′(t) = au(t)+bu([K/N* t]) is dealed with, where K and N is relatively prime and K < N,K,N∈ Z+. The conditions are obtained under which the numerical solutions preserve the analytical stability properties of the analytic ones and some numerical experiments are given.
基金Project supported by the National Natural Science Foundation of China (Grant No.12071042)Beijing Natural Science Foundation (Grant No.1202006)。
文摘Under consideration in this study is the discrete coupled modified Korteweg-de Vries(mKdV)equation with 4×4 Lax pair.Firstly,through using continuous limit technique,this discrete equation can be mapped to the coupled KdV and mKdV equations,which may depict the development of shallow water waves,the optical soliton propagation in cubic nonlinear media and the Alfven wave in a cold collision-free plasma.Secondly,the discrete generalized(r,N-r)-fold Darboux transformation is constructed and extended to solve this discrete coupled equation with the fourth-order linear spectral problem,from which diverse exact solutions including usual multi-soliton and semi-rational soliton solutions on the vanishing background,higher-order rational soliton and mixed hyperbolic-rational soliton solutions on the non-vanishing background are derived,and the limit states of some soliton and rational soliton solutions are analyzed by the asymptotic analysis technique.Finally,the numerical simulations are used to explore the dynamical behaviors of some exact soliton solutions.These results may be helpful for understanding some physical phenomena in fields of shallow water wave,optics,and plasma physics.
文摘Studying the dynamic changes in the coastline of the northeastern Caspian Sea is significant since the level of the Caspian is unstable,and the coastline change can cause enormous damage to the ecology,economy,and population of the coastal part of Kazakhstan.In this work,we use remote sensing and Geographic Information System(GIS)technologies to study the changes in the coastline of the northeastern Caspian Sea and predict the extent of flooding with increasing water levels.The proposed methodology for creating dynamic maps can be used to monitor the coastline and forecast the extent of flooding in the area.As a result of this work,the main factors affecting changes in the coastline were identified.After analyzing the water level data from 1988 to 2019,it was revealed that the rise in water level was observed from 1980 to 1995.The maximum sea level rise was recorded at-26.04 m.After that,the sea level began to fall,and between 1996 and 2009,there were no significant changes;the water level fluctuated with an average of-27.18 m.Then,a map of the water level dynamics in the Caspian Sea from 1988 to 2019 was compiled.According to the dynamics map,water level rise and significant coastal retreat were revealed,especially in the northern part of the Caspian Sea and the northern and southern parts of Sora Kaydak.The method for predicting the estimated flooding area was described.As a result,based on a single map,the flooding area of the northeast coast was predicted.A comparative analysis of Landsat and SRTM data is presented.
文摘Renewable energy has garnered attention due to the need for sustainable energy sources.Wind power has emerged as an alternative that has contributed to the transition towards cleaner energy.As the importance of wind energy grows,it can be crucial to provide forecasts that optimize its performance potential.Artificial intelligence(AI)methods have risen in prominence due to how well they can handle complicated systems while enhancing the accuracy of prediction.This study explored the area of AI to predict wind-energy production at a wind farm in Yalova,Turkey,using four different AI approaches:support vector machines(SVMs),decision trees,adaptive neuro-fuzzy inference systems(ANFIS)and artificial neural networks(ANNs).Wind speed and direction were considered as essential input parameters,with wind energy as the target parameter,and models are thoroughly evaluated using metrics such as the mean absolute percentage error(MAPE),coefficient of determination(R~2),and mean absolute error(MAE).The findings accentuate the superior performance of the SVM,which delivered the lowest MAPE(2.42%),the highest R~2(0.95),and the lowest MAE(71.21%)compared with actual values,while ANFIS was less effective in this context.The main aim of this comparative analysis was to rank the models to move to the next step in improving the least efficient methods by combining them with optimization algorithms,such as metaheuristic algorithms.
基金Project supported by the National Natural Science Foundation of China (Grant Nos. 12034012, 12074231, 12274272, and 61827824)Science and technology innovation plan of colleges and universities in Shanxi Province (Grant No. 2021L313)+2 种基金Science and Technology Project of State Grid (Grant No. 5700-202127198A-0-0-00)Fundamental Research Program of Shanxi Province (Grant No. 202203021222204)Taiyuan University of Science and Technology Scientific Research Initial Funding (Grant Nos. 20222008 and 20222132)。
文摘We demonstrate a simple method to measure electric field intensity by using doublet electromagnetically induced transparency(EIT) spectra of cold Rb Rydberg atoms, where the frequency of the coupling laser does not need to be locked. Based on the Stark splitting of the Rb Rydberg state, 10D_(3/2), under electric fields and the corresponding calculated polarizabilities, the real electric field intensity is calculated using the difference in radio-frequency diffraction between two acousto-optic modulators, which acts as a frequency criterion that allows us to measure the electrical field without locking the coupling laser. The value measured by this simple method shows a good agreement with our previous work [Opt.Express 29 1558(2021)] where the frequency of the coupling laser needs to be locked with an additional EIT spectrum based on atom vapor and a proportional–integral–differential feedback circuit. Our presented method can also be extended to the measurement of electric field based on hot Rydberg atom vapor, which has application in industry.
文摘Mobile Ad hoc Network(MANET)is decentralized wireless network and can communicate without existing infrastructure in many areas.MANET is vulnerable to various attacks that affect its performance such as blackhole attack.Blackhole attacker,inject fault routing information to persuade the source node to select the path with malicious node as the shortest path.To eliminate malicious nodes from launching any collaborative attack.A cooperative Trapping Approach(CTA)was proposed based on modifying Ad-hoc On-demand Distance Vector(AODV)routing protocol and trapping the malicious nodes by responding to the trap request message.The approach aims to eliminate and rule out both single and collaborative malicious blackhole nodes from any attack.The approach realizes a backward tracking mechanism to perform the elimination process.The proposed algorithm(CTA)was executed using NS-2 network simulator.The performance metrics that has been considered to evaluate the performance of the proposed algorithm such as throughput,end to end delay,packet delivery ratio,and consuming energy.The experimental results have shown the performance metrics of the proposed approach outperformed other state of at algorithms.
基金The authors Kamal Shah,and Thabet Abdeljawad would like to thank Prince Sultan University for paying the APC.
文摘In this work,we present a model that uses the fractional order Caputo derivative for the novel Coronavirus disease 2019(COVID-19)with different hospitalization strategies for severe and mild cases and incorporate an awareness program.We generalize the SEIR model of the spread of COVID-19 with a private focus on the transmissibility of people who are aware of the disease and follow preventative health measures and people who are ignorant of the disease and do not follow preventive health measures.Moreover,individuals with severe,mild symptoms and asymptomatically infected are also considered.The basic reproduction number(R0)and local stability of the disease-free equilibrium(DFE)in terms of R0 are investigated.Also,the uniqueness and existence of the solution are studied.Numerical simulations are performed by using some real values of parameters.Furthermore,the immunization of a sample of aware susceptible individuals in the proposed model to forecast the effect of the vaccination is also considered.Also,an investigation of the effect of public awareness on transmission dynamics is one of our aim in this work.Finally,a prediction about the evolution of COVID-19 in 1000 days is given.For the qualitative theory of the existence of a solution,we use some tools of nonlinear analysis,including Lipschitz criteria.Also,for the numerical interpretation,we use the Adams-Moulton-Bashforth procedure.All the numerical results are presented graphically.
基金supported by the Basic Science Research Program of the National Research Foundation(NRF)of South Koreafunded by the Ministry of Science&ICT and Future Planning(NRF-2020M3H4A3081889)KIST Institutional Program of South Korea(Project Nos.2E31860)。
文摘Elucidation of a reaction mechanism is the most critical aspect for designing electrodes for highperformance secondary batteries.Herein,we investigate the sodium insertion/extraction into an iron fluoride hydrate(FeF_(3)·0.5H_(2)O)electrode for sodium-ion batteries(SIBs).The electrode material is prepared by employing an ionic liquid 1-butyl-3-methylimidazolium-tetrafluoroborate,which serves as a reaction medium and precursor for F^(-)ions.The crystal structure of FeF_(3)·0.5H_(2)O is observed as pyrochlore type with large open 3-D tunnels and a unit cell volume of 1129A^(3).The morphology of FeF_(3)·0.5H_(2)O is spherical shape with a mesoporous structure.The microstructure analysis reveals primary particle size of around 10 nm.The FeF_(3)·0.5H_(2)O cathode exhibits stable discharge capacities of 158,210,and 284 mA h g^(-1) in three different potential ranges of 1.5-4.5,1.2-4.5,and 1.0-4.5 V,respectively at 0.05 C rate.The specific capacities remained stable in over 50 cycles in all three potential ranges,while the rate capability was best in the potential range of 1.5-4.5 V.The electrochemical sodium storage mechanism is studied using X-ray absorption spectroscopy,indicating higher conversion at a more discharged state.Ex-situ M?ssbauer spectroscopy strengthens the results for reversible reduction/oxidation of Fe.These results will be favorable to establish high-performance cathode materials with selective voltage window for SIBs.
