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Correlation of Rainfall Anomalies in Rwanda from September to December (SOND) with Indian Ocean Dipole (IOD) and El Nino Southern Oscillation (ENSO) Events

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Journal of Geoscience and Environment Protection 2024年第6期12卷 115-134页

作者： Frank Rusanganwa Ling Zhang Jonah Kazora Joseph Ndakize Sebaziga samuel Ekwacu College of Atmospheric Science Nanjing University of Information Science and Technology Nanjing China Rwanda Meteorology Agency (Meteo-Rwanda) Kigali Rwanda School of Science and Technology University of Rwanda Kigali Rwanda Uganda National Meteorological Authority (UNMA) Kampala Uganda

Understanding the relationship between rainfall anomalies and large-scale systems is critical for driving adaptation and mitigation strategies in socioeconomic sectors. This study therefore aims primarily to investigate the correlation between rainfall anomalies in Rwanda during the months of September to December (SOND) with the occurrences of Indian Ocean Dipole (IOD) and El Nino Southern Oscillation (ENSO) events. The study is useful for early warning and forecasting of negative effects associated with extreme rainfall anomalies across the country, using Climate Hazards Group InfraRed Precipitation with Station (CHIRPS), the National Centers for Environmental Prediction (NCEP) National Center for Atmospheric Research (NCAR) reanalysis sea surface temperature and ERA5 reanalysis datasets, during the period of 1983-2021. Both empirical orthogonal function (EOF), correlation analysis and composite analysis were used to delineate variability, relationship and the related atmospheric circulation between Rwanda seasonal rainfall September to December (SOND) with Indian Ocean Dipole (IOD) and El-Nino Southern Oscillation (ENSO). The results for Empirical Orthogonal Function (EOF) for the reconstructed rainfall data set showed three modes. EOF-1, EOF-2 and EOF-3 with their total variance of 63.6%, 16.5% and 4.8%, Indian ocean dipole (IOD) events resulted to a strong positive correlation of rainfall anomalies and Dipole model index (DMI) (r = 0.42, p value = 0.001, DF = 37) significant at 95% confidence level. The composite analysis for the reanalysis dataset was carried out to show the circulation patterns during four different events correlated with September to December seasonal rainfall in Rwanda using T-test at 95% confidence level. Wind anomaly revealed that there was a convergence of south westerly winds and easterly wind over the study area during positive Indian Ocean Diploe (PIOD) and PIOD with El Nino concurrence event years. The finding of this study will cont

关键词： Correlation Rainfall Anomalies Rwanda Indian Ocean Dipole El Nino Southern Oscillation

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Optimization of bio-oil production parameters from the pyrolysis of elephant grass (Pennisetum purpureum) using response surface methodology

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Clean Energy 2024年第5期8卷 241-251页

作者： Sunday C.Ikpeseni samuel O.Sada Ufuoma J.Efetobor Henry O.Orugba Mathias Ekpu Hilary I.Owamah Jeremiah L.Chukwuneke Solomon Oyebisi Uche P.Onochie Department of Mechanical Engineering Delta State UniversityP.M.B.1AbrakaNigeria Department of Mechanical Engineering Delta State PolytechnicP.M.B.3Otefe-OgharaNigeria Department of Chemical Engineering Delta State UniversityP.M.B.1AbrakaNigeria Department of Civil Engineering Delta State UniversityP.M.B.1AbrakaNigeria Department of Mechanical Engineering Nnamdi Azikiwe UniversityP.M.B.2025AwkaNigeria Department of Civil Engineering Covenant UniversityP.M.B.1023OttaNigeria Department of Civil Engineering The University of the South PacificP.M.B.9072SuvaFiji Department of Mechanical Engineering Delta State University of Science and TechnologyP.M.B.5OzoroNigeria

The need to increase bio-oil yield from biomass and enhance its fuel properties has driven research into optimizing the pyrolysis *** study investigated the influence of three key process parameters—temperature,heating rate,and nitrogen flow rate—on the pyrolysis of elephant grass(Pennisetum purpureum)in a fixed-bed *** surface methodology was used to study the im-pact of the aforementioned variables on bio-oil yield to improve its production *** analysis of the biomass revealed 79.24 wt%volatile matter,14.22 wt%fixed carbon,and 5.86%ash,with ultimate analysis showing 45.44%carbon,5.59%hydrogen,and 40.95%*** high volatile matter content and favourable carbon and hydrogen percentages indicate that elephant grass is a vi-able energy source due to its potential for high bio-oil yield and energy *** resulting bio-oil exhibited a higher heating value of 20.9 MJ/kg,indicating its suitability for various heating applications.A second-order regression model was developed for bio-oil yield,with optimal conditions identified as a temperature of 550°C,a heating rate of 17°C/min,and a nitrogen flow rate of 6 ml/*** study achieved an optimal bio-oil yield of 59.03 wt%,and the model’s high R²value of 0.8683 from analysis of variance analysis confirmed its predictive *** research highlights elephant grass as a sustainable feedstock for bio-oil production,offering valuable insights into optimizing pyrolysis conditions to enhance bio-oil yield,thus advancing biofuel technology.

关键词： renewable energy biomass sustainable feedstock regression model fixed-bed reactor

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Structural,morphological,optical and antibacterial performances of rare earth(Sm)-doped ZnO nanorods

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Journal of Rare Earths 2024年第11期42卷 2119-2127页

作者： A.Ravi J.samuel S.Sahaya Jude Dhas S.Usharani Turibius Simon D.Senthil Kumar S.K.Jasmin Vijitha A.Sivakumar Raju Suresh Kumar C.S.Biju Department of Physics University College of Engineering Department of Physics and Research Centre Malankara Catholic College Manonmaniam Sundaranar University Saveetha School of Engineering Saveetha Institute of Medical and Technical SciencesSaveetha University Department of Chemistry S.I.V.E.T College Department of Biotechnology Vivekanandha College of Arts and Science for Woman (Autonomous) Department of Physics Vel Tech Rangarajan Dr.Sagunthala R & D Institute of Science and Technology Department of Physics & Research Centre Muslim Arts College Key Laboratory of High-temperature and High-pressure Study of the Earth's Interior Institute of GeochemistryChinese Academy of Sciences Department of Chemistry College of ScienceKing Saud University Department of Physics St. Alphonsa College of Arts and Science

The significant rise of ultra-violet（UV） radiation and pathogenic infectious bacteria poses a serious threat to global *** researchers' interests are attracted by novel materials with strong UVblocking ability,antibacterial activity and low toxicity to other *** this case,a simple wet chemical method with different annealing temperatures（400,500,and 600℃） was employed to create highly effective rare earth（Sm）-doped ZnO ***（101） plane of wurtzite ZnO shifts towards a lower angle with increasing annealing temperature,according to the X-ray diffraction（XRD） study findings,which additionally establishes the consequence of lattice *** of doublet peaks of Sm 3d(Sm 3d5/2and Sm 3d3/2) in the X-ray photoelectron spectroscopy（XPS） spectrum clearly validates the substitution of Sm3+ions in the 500℃-annealed *** 500℃-annealed nanorods exhibit combined performances of the wide band gap,improved UV absorbance,and vivid green luminescent emission（563 nm）.Additio nally,the nanorods have favorable UV-blocking execution of 96% for UVA at 360 nm,92% for UVB at 320 nm,and 57% for UVC at 225 nm,which is greater than the majority of ZnO-related materials that have been reported up to this *** doping is also appropriate for improving bacterial inhibition against the two studied strains（Escherichia coli and Staphylococcus aureus）,in addition to the intriguing features discussed ***,with maximum inhibition zone diameters of 20±0.72 and 18±0.57 mm,respectively,these nanorods exhibit high inhibitory action against *** and *** bacterial *** rare earth-doped material developed during the current experiment,which was annealed at 500℃,could potentially serve as an effective replacement for UV-blocking and antibacterial material,especially for biomedical applications.

关键词： Wet chemical method rare earth doping Metal oxide UV-Shielding Bacterial inhibition

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Assessing the Impact of Gold Mining on the Quality of Water Resources in the Commune of Meguet, Burkina Faso

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Journal of Water Resource and Protection 2024年第4期16卷 281-292页

作者： Issoufou Ouedraogo samuel Lankoande Yacouba Konate Boukary Sawadogo Nicolas Kagambega Martin Lompo Higher School of Engineering (ESI) University of Fada N&#8217Gourma Fada N&#8217Gourma Burkina Faso Geosciences and Environment Laboratory (LaGE) Joseph KI-ZERBO University Ouagadougou Burkina Faso Water Hydro-Systems and Agriculture Laboratory (LEHSA) International Institute of Water and Environmental Engineering (2iE) Ouagadougou Burkina Faso

Despite its often illegal nature, artisanal gold mining in Burkina Faso contributes to the economic and social development of the country. However, the rudimentary techniques used in gold panning have a significant impact on the environment due to inappropriate practices and the use of various chemical substances. This study aims to assess the impact of artisanal gold mining on the quality of water resources in a rural community at Méguet, Burkina Faso. To this end, surface and groundwater samples were collected and analyzed at the BUMIGEB laboratory. Field results show that the waters are slightly alkaline (6.97 < pH < 8.1), weakly mineralized and conductive (124 < EC < 543 μS/cm), with temperatures ranging from 24.6˚C to 31.6˚C. In addition, trace metals (TMEs) analyzed from surface and subsurface waters show very high levels, generally deviating from the levels recommended by WHO guidelines for Burkina Faso. Trace metals contamination of water resources in the commune of Méguet is mainly due to Fe (3.78 - 11.12 mg/kg), Hg (0.03 - 0.29 mg/kg), As (0.01- 6.31 mg/kg) and Pb (0.01 - 3.8 mg/kg). This study can serve as a basis for guiding national environmental policies to protect the water resources of the Méguet mine.

关键词： Gold Panning Water Quality Trace Metal Méguet Burkina Faso

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Effects of Supplemental Glutamine and Lysine on Growth Performance of Broiler Chickens

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Open Journal of Animal Sciences 2024年第2期14卷 101-122页

作者： Ali F. Alsogair Naif M. Alhawiti samuel N. Nahashon National Center for Wildlife Riyadh KSA California Animal Health and Food Safety Laboratory University of California Davis Davis USA Department of Agricultural and Environmental Sciences College of Agriculture Tennessee State University Nashville Tennessee USA

The optimum levels of Lysine and Glutamine needed for growth performance and maintenance of the chicken broilers were evaluated in a randomized 3 × 4 factorial arrangement of dietary treatments. The battery cages measured 99 × 66 × 25 cm that can be sufficient for 5 birds. Day old Chicken broilers totaling 180 were assigned to dietary treatments comprising of 3 concentrations of Lysine (0.85, 1.14, and 1.42) each in combination with 4 concentrations of Glutamine (0, 1, 2, and 3). Each dietary treatment was replicated 3 times and each replication had 5 birds. The birds were given feed and water ad libitum with a 23-hour light regimen for a period of 4 weeks. Then, the experimental birds were evaluated for body weight gain, feed consumption, and feed conversion in order to determine their optimum requirement for dietary Lysine and Glutamine. Based on the findings of this study, the highest performance was observed in birds fed the diet supplemented with 1.42 lysine and 1% glutamine, but the highest improvement in feed conversion was observed in diet contain 1.14 and 1.42 with 1% and 3% glutamine, respectively. Birds fed 1.42 lysine and 1% glutamine had the highest total body weight gain and feed consumption. The lysine requirements in the diet for Chicken are between 1.14 and 1.42 with glutamine level of 1%.

关键词： Broiler Chickens Lysine Glutamine Amino Acid Dietary Protein Essentials AAs Non-Essential Amino Acids

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Modelling the Survival of Western Honey Bee Apis mellifera and the African Stingless Bee Meliponula ferruginea Using Semiparametric Marginal Proportional Hazards Mixture Cure Model

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Journal of Data Analysis and Information Processing 2024年第1期12卷 24-39页

作者： Patience Isiaho Daisy Salifu samuel Mwalili Henri E. Z. Tonnang Department of Statistics and Actuarial Sciences Jomo Kenyatta University of Agriculture and Technology Nairobi Kenya Data Management Modelling and Geo-Information Unit International Centre of Insect Physiology and Ecology (icipe) Nairobi Kenya

Classical survival analysis assumes all subjects will experience the event of interest, but in some cases, a portion of the population may never encounter the event. These survival methods further assume independent survival times, which is not valid for honey bees, which live in nests. The study introduces a semi-parametric marginal proportional hazards mixture cure (PHMC) model with exchangeable correlation structure, using generalized estimating equations for survival data analysis. The model was tested on clustered right-censored bees survival data with a cured fraction, where two bee species were subjected to different entomopathogens to test the effect of the entomopathogens on the survival of the bee species. The Expectation-Solution algorithm is used to estimate the parameters. The study notes a weak positive association between cure statuses (ρ1=0.0007) and survival times for uncured bees (ρ2=0.0890), emphasizing their importance. The odds of being uncured for A. mellifera is higher than the odds for species M. ferruginea. The bee species, A. mellifera are more susceptible to entomopathogens icipe 7, icipe 20, and icipe 69. The Cox-Snell residuals show that the proposed semiparametric PH model generally fits the data well as compared to model that assume independent correlation structure. Thus, the semi parametric marginal proportional hazards mixture cure is parsimonious model for correlated bees survival data.

关键词： Mixture Cure Models Clustered Survival Data Correlation Structure Cox-Snell Residuals EM Algorithm Expectation-Solution Algorithm

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Comparison of Semi-Parametric Shared Frailty Models for Bees’Survival

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Journal of Data Analysis and Information Processing 2024年第2期12卷 267-288页

Survival analysis is a fundamental tool in medical science for time-to-event data. However, its application to colony organisms like bees poses challenges due to their social nature. Traditional survival models may not accurately capture the interdependence among individuals within a colony. Frailty models, accounting for shared risks within groups, offer a promising alternative. This study evaluates the performance of semi-parametric shared frailty models (gamma, inverse normal, and positive stable-in comparison to the traditional Cox model using bees’ survival data). We examined the effect of misspecification of the frailty distribution on regression and heterogeneity parameters using simulation and concluded that the heterogeneity parameter was more sensitive to misspecification of the frailty distribution and choice of initial parameters (cluster size and true heterogeneity parameter) compared to the regression parameter. From the data, parameter estimates for covariates were close for the four models but slightly higher for the Cox model. The shared gamma frailty model provided a better fit to the data in comparison with the other models. Therefore, when focusing on regression parameters, the gamma frailty model is recommended. This research underscores the importance of tailored survival methodologies for accurately analyzing time-to-event data in social organisms.

关键词： Correlated Failure Times Frailty Survival Analysis Unobserved Heterogeneity

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Investigation of Acoustomagnetoelectric Effect in Bandgap Graphene by the Boltzmann Transport Equation

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World Journal of Condensed Matter Physics 2024年第1期14卷 10-20页

作者： Raymond Edziah samuel S. Bentsiefi Kwadwo Dompreh Anthony Twum Emmanuel Kofi Amewode Patrick Mensah-Amoah Ebenezer T. Tatchie Cynthia Jebuni-Adanu samuel Y. Mensah Department of Physics University of Cape Coast Cape Coast Ghana Department of Physics Education University of Education Winneba Ghana

We study the acoustomagnetoelectric (AME) effect in two-dimensional graphene with an energy bandgap using the semiclassical Boltzmann transport equation within the hypersound regime, (where represents the acoustic wavenumber and is the mean free path of the electron). The Boltzmann transport equation and other relevant equations were solved analytically to obtain an expression for the AME current density, consisting of longitudinal and Hall components. Our numerical results indicate that both components of the AME current densities display oscillatory behaviour. Furthermore, geometric resonances and Weiss oscillations were each defined using the relationship between the current density and Surface Acoustic Wave (SAW) frequency and the inverse of the applied magnetic field, respectively. Our results show that the AME current density of bandgap graphene, which can be controlled to suit a particular electronic device application, is smaller than that of (gapless) graphene and is therefore, more suited for nanophotonic device applications.

关键词： Boltzmann Transport Equation Acoustomagnetoelctric Effect Surface Acoustic Wave Gapless Graphene Weiss Oscillations

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A prospective cohort of men with localized prostate cancer on active surveillance protocol in Hong Kong,China:what did we learn?

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Asian Journal of Andrology 2024年第3期26卷 245-249页

作者： Xiaobo Wu Ivan Ching-Ho Ko Cindy Yeuk-Lam Hong samuel Chi-Hang Yee Jeremy Yuen-Chun Teoh Samson Yun-Sang Chan Ho-Man Tam Chi-Kwok Chan Chi-Fai Ng Peter Ka-Fung Chiu SH Ho Urology Centre Department of SurgeryFaculty of MedicineThe Chinese University of Hong KongHong KongChina

This study aimed to report the outcomes of active surveillance(AS)in the management of low-risk prostate cancer(PCa).It recruited87 men who were prospectively followed up according to the Prostate Cancer Research International Active Surveillance(PRIAS)protocol with local adaptation at SH Ho Urology Centre,Prince of Wales Hospital,Hong Kong,*** investigated the predictorsof disease progression and found that baseline prostate-specific antigen density(PSAD)and the presence of the highest ProstateImaging-Reporting and Data System(PI-RADS)score 5 lesion on magnetic resonance imaging(MRI)are significantly correlatedwith disease ***,men with PSAD>0.2 ng ml^(−2)or PI-RADS 4 or 5 lesions had significantly worse upgradingfree survival compared to those with PSAD≤0.2 ng ml−2 and PI-RADS 2 or 3 *** study concludes that AS is a safe andeffective management strategy for selected patients to defer radical treatment and that most disease progression can be detectedafter the first repeated *** combination of PSAD>0.2 ng ml^(−2)and PI-RADS 4 or 5 lesions may serve as a useful predictorof early disease progression and provide a guide to optimize follow-up protocols for men in different risk groups.

关键词： active surveillance cohort localized prostate cancer

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New avenues for the treatment of immunotherapy-resistant pancreatic cancer

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World Journal of Gastrointestinal Oncology 2024年第4期16卷 1134-1153页

作者： Luis Guilherme de Oliveira Silva Fabian Fellipe Bueno Lemos Marcel Silva Luz samuel Luca Rocha Pinheiro Mariana dos Santos Calmon Gabriel Lima Correa Santos Gabriel Reis Rocha Fabrício Freire de Melo Instituto Multidisciplinar em Saúde Universidade Federal da BahiaVitória da Conquista 45029-094BahiaBrazil

Pancreatic cancer(PC)is characterized by its extremely aggressive nature and ranks 14th in the number of new cancer cases ***,due to its complexity,it ranks 7th in the list of the most lethal cancers *** pathogenesis of PC involves several complex processes,including familial genetic factors associated with risk factors such as obesity,diabetes mellitus,chronic pancreatitis,and *** in genes such as KRAS,TP53,and SMAD4 are linked to the appearance of malignant cells that generate pancreatic lesions and,consequently,*** this context,some therapies are used for PC,one of which is immunotherapy,which is extremely promising in various other types of cancer but has shown little response in the treatment of PC due to various resistance mechanisms that contribute to a drop in immunotherapy *** is therefore clear that the tumor microenvironment(TME)has a huge impact on the resistance process,since cellular and non-cellular elements create an immunosuppressive environment,characterized by a dense desmoplastic stroma with cancerassociated fibroblasts,pancreatic stellate cells,extracellular matrix,and immunosuppressive *** to this are genetic mutations in TP53 and immunosuppressive factors that act on T cells,resulting in a shortage of CD8+T cells and limited expression of activation markers such as *** this way,finding new strategies that make it possible to manipulate resistance mechanisms is ***,techniques such as the use of TME modulators that block receptors and stromal molecules that generate resistance,the use of genetic manipulation in specific regions,such as microRNAs,the modulation of extrinsic and intrinsic factors associated with T cells,and,above all,therapeutic models that combine these modulation techniques constitute the promising future of PC ***,this study aims to elucidate the main mechanisms of resistance to immunotherapy in PC and new ways of manipulating thi

关键词： Pancreatic cancer Immunotherapy Resistance Tumor microenvironment manipulation Combined immunotherapy

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