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Post-fire recovery of Puya raimondii, vegetation and birds in the puna of Huascarán National Park, Perú

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Journal of Mountain Science 2024年第1期21卷 20-32页

作者： Mery L.SUNI Giovana P.VADILLO César ArANA Enoc JArA-PENA Letty SALINAS M.Estela PONCE Paul M.rAMSAY Plant Physiology Laboratory Faculty of Biological SciencesUniversidad Nacional Mayor de San MarcosLima 15081Peru Natural History Museum Universidad Nacional Mayor de San MarcosLima 15072Peru Applied Phytology Laboratory Faculty of Biological SciencesUniversidad Nacional Mayor de San MarcosLima 15081Peru Department of Statistics Faculty of Mathematical SciencesUniversidad Nacional Mayor de San MarcosLima 15081Peru Department of Chemical and Biological Sciences Universidad de las Américas PueblaSan Andrés Cholula CP Cholula CP 72810Mexico

A large fire of 233 ha in Huascarán National Park in Peru provided an opportunity to compare plant and bird responses in burned and nearby unburned zones of the puna. Heights and live diameters of flagship Puya raimondii rosettes(assigned to four broad developmental phases), plant communities(66 species in 24 families and nine growth forms) and bird communities(77 species in six trophic guilds) were monitored after the fire. Although no mortality was observed, Puya raimondii plants were affected by the fire, losing approximately 60% of their photosynthetic area across all developmental phases, but recovered quickly during the first two years after fire. The comparison of Puya rosette recovery after fire was complicated by the changes in live rosette diameter for unburned plants, which showed plasticity of photosynthetic area linked to seasonal and annual fluctuations in precipitation in this relatively dry environment(decreased by 26% for mature adult plants over the study period). Fire caused an immediate change in the density, biomass and composition of vegetation. Although the species present remained similar, their abundances changed significantly immediately after the fire, with notable reductions in dominant tussock grasses. This provided opportunities for other plants, resulting in higher postfire diversity of plant species, genera, families and growth forms. In turn, the changes in vegetation after fire affected the composition of birds according to their trophic guild. Granivores largely disappeared,generalists were mostly unaffected, and other guilds showed a more complex response. As the vegetation recovered, most displaced birds returned within approximately one year.

关键词： Burning Plant biomass Trophic guilds Andes Giant rosette plants

Prediction of Low Heating Value of Sugar Cane Bagasse as a Fuel for Industrial Boilers in the High relative Humidity region: Case of Cameroon

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Open Journal of Applied Sciences 2024年第6期14卷 1604-1624页

作者： Pierre Kana-Donfack Maxell Tientcheu-Nsiewe Denis Tcheukam-Toko César Kapseu Department of Mechanical Engineering College of Technology University of Buea Buea Cameroon Department of Fundamental Sciences and Engineering Technology School of Chemical Engineering and Mineral Industries University of Ngaoudr Ngaoudr Cameroon Department of Process Engineering National School of Agro-Industrial Science University of Ngaoundr Ngaoudr Cameroon

Many attempts have been made to estimate calorific value of bagasse using mathematical equations, which were created based on data from proximate, ultimate, physical and chemical analysis. Questions have been raised on the applicability of these equations in different parts of the globe. This study was initiated to tackle these problems and also check the most suited mathematical models for the Law Heating Value of Cameroonian bagasse. Data and bagasse samples were collected at the Cameroonian sugarcane factory. The effects of cane variety, age of harvesting, source, moisture content, and sucrose on the LHV of Cameroon bagasse have been tested. It was shown that humidity does not change within a variety, but changes from the dry season to the rainy season;the sugar in the rainy season is significantly different from that collected in the dry season. Samples of the same variety have identical LHV. LHV in the dry season is significantly different from LHV in the rainy season. According to the fact that this study was done for cane with different ages of harvesting, the maturity of Cameroonian sugarcane does not affect LHV of bagasse. Tree selected models are much superior tool for the prediction of the LHV for bagasse in Cameroon compared to others. The standard deviation of these validated models is around 200 kJ/kg compared to the experimental. Thus, the models determined in foreign countries, are not necessarily applicable in predicting the LHV of bagasse in other countries with the same accuracy as that in their native country. There was linear relationship between humidity, ash and sugar content in the bagasse. It is possible to build models based on data from physical composition of bagasse using regression analysis.

关键词： Sugarcane Bagasse relative Humidity Ash Low Heating Value

Corrective Effect of the Angle of Incidence of the Magnetic Field Intensity on the Performance (Series and Shunt resistances) of a Bifacial Silicon Solar Cell

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Energy and Power Engineering 2024年第9期16卷 313-323页

作者： Idrissa Sourabié Mahamadi Savadogo Boubacar Soro ramatou saré Christian Zoundi Martial Zoungrana Issa Zerbo Laboratoire de Chimie Analytique de Physique Spatiale et nergtique (L@CAPSE) Ecole Doctorale Sciences et Technologies Universit Norbert ZONGO Koudougou Burkina Faso Laboratoire dEnergies Thermiques renouvelables (L.E.T.rE) Ecole Doctorale Sciences et Technologies Universit Joseph KI-ZERBO Ouagadougou Burkina Faso

This article presents a three-dimensional analysis of the impact of the angle of incidence of the magnetic field intensity on the electrical performance (series resistance, shunt resistance) of a bifacial polycrystalline silicon solar cell. The cell is illuminated simultaneously from both sides. The continuity equation for the excess minority carriers is solved at the emitter and at the depth of the base respectively. The analytical expressions for photocurrent density, photovoltage, series resistance and shunt resistance were deduced. Using these expressions, the values of the series and shunt resistances were extracted for different values of the angle of incidence of the magnetic field intensity. The study shows that as the angle of incidence increases, the slopes of the minority carrier density for the two modes of operation of the solar cell decrease. This is explained by a drop in the accumulation of carriers in the area close to the junction due to the fact that the Lorentz force is unable to drive the carriers towards the lateral surfaces due to the weak action of the magnetic field, which tends to cancel out as the incidence angle increases, and consequently a drop in the open circuit photovoltage. This, in turn, reduces the Lorentz force. These results predict that the p-n junction of the solar cell will not heat up. The study also showed a decrease in series resistance as the incidence angle of the magnetic field intensity increased from 0 rad to π/2 rad and an increase in shunt resistance as the incidence angle increased. His behaviour of the electrical parameters when the angle of incidence of the field from 0 rad to π/2 rad shows that the decreasing magnetic field vector tends to be collinear with the electron trajectory. This allows them to cross the junction and participate in the external current. The best orientation for the Lorentz force is zero, in which case the carriers can move easily towards the junction.

关键词： Angle of Incidence Magnetic Field Intensity Bifacial Polycrystalline Silicon Solar Cell Series resistance Shunt resistance

Growth Efficiency of Local Chickens Using Sweet Potato Vine with Concentration Feed as a Basal Diet

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Journal of Environmental Science and Engineering(B) 2024年第3期13卷 108-113页

作者： Hieak Hun Suheang Sorn Chan Bun Manay Ith Ty Chhay Kouch Theng Chetra sar Faculty of Animal Sciences Royal University of AgriculturePhnom Penh 12400Cambodia General Directorate of Animal Health and Production Phnom Penh 120603Cambodia Faculty of Veterinary Medicine Royal University of AgriculturePhnom Penh 12400Cambodia Ministry of Environment Sangkat Tonle BasakKhan Chamkar MonPhnom Penh 120101Cambodia Ministry of Agriculture Forestry and FisheriesSangkat Tonle BasakKhan Chamkar MonPhnom Penh 120101Cambodia Graduate School Royal University of AgriculturePhnom Penh 12400Cambodia

The experiment was conducted at the animal experimental station of the Faculty of Animal Sciences,royal University of Agriculture,commenced from 10 January to 14 March,*** CrD(Completely randomized Design)was used with 5 treatments and 4 *** 500 chicks at one-day-old,local bread,were purchased from farmers who run their small scale hatchery *** chicks were kept together till 21 days old,and then were allocated randomly into in five diets(treatments),25 chicks per *** feed formulas for this study were designed and calculated to maintain a protein content of approximately 17%,dividing into 5 feed formulas(Treatments),such as concentrated feed only(control treatment:T0),plus 10%of fresh sweet potato vine(T1),plus 20%of fresh sweet potato vine(T2),plus 30%of fresh sweet potato vine(T3)and plus 20%of sweet potato vine meal(T4).The results showed that the treatment T1,had a similar final weight with the treatment T4,but was slightly lower than the treatment T0 which used concentrated feed *** intake and FCr(Feed Conversion ratio)were not significantly different among those *** conclusion,the average daily weight gain of chickens seemed to decrease with increasing the level of fresh sweet potato ***,the optimum level of fresh sweet potato vine was 10%,which may have little effect on the growth performance of local *** addition,it was not far different from the positive control treatment and the treatment using sweet potato vine ***,the producers can increase the amount of sweet potato vine in feed formula by processing it into meal and mixing with concentrated feed or using as feed ingredients.

关键词： Local breed final weight feed intake FCr

Coupling Aquaculture—Crop Productions and Using of Water Drained from Ponds rearing Clarias gariepinus as Fertilizer for Okra Production (Abelmoschus esculentus var. Clemson spineless, L. Moench)

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Open Journal of Applied Sciences 2024年第9期14卷 2628-2647页

作者： Louis Dossou Magblénou Justin Kantoussan César Bassène Dieynaba Yacine Mar Gueye Hamath Sy Laboratoire des Sciences Biologiques Agronomiques et de Modlisation des Systmes Complexes (LaBAM) UFR des Sciences Agronomiques de lAquaculture et des Technologies Alimentaires (UFR S2ATA) Dpartement Aquaculture Universit Gaston Berger (UGB) Saint-Louis Senegal Laboratoire des Sciences Biologiques Agronomiques et de Modlisation des Systmes Complexes (LaBAM) UFR des Sciences Agronomiques de lAquaculture et des Technologies Alimentaires (UFR S2ATA) Dpartement Productions Vgtales et Agronomie (PVA) Universit Gaston Berger (UGB) Saint-Louis Senegal

The present study concerns the revalorization of drained water from aquaculture ponds rearing Clarias gariepinus on okra crops. The rearing was carried out at the farm of Gaston Berger University in 100 m2 ponds. In each pond, the individuals of C. garipinus with an average weight of 6 ± 0.3 g were stocked at a density of 11 per m2. The water temperature and pH were measured during the experiment. The control fishing is carried out every month to monitor variations in the weight and size of reared individuals. The plant production is carried out in elementary plots measuring 3 m × 1.5 m. Each plot was fertilized with either: drained water from C. gariepinus rearing (DWC), poultry droppings (PD), cow dung (CD) and mineral fertilizer (NPK). Treatments are carried out in tripliqua with either river water (rW), rW + the recommended dose of NPK (rD-NPK), rW + rD-PD, rW + rD-CD, DWC, DWC + 25% rD-NPK, DWC + 50% rD-NPK, DWC + 75% rD-NPK, DWC + 25% rD-PD, DWC + 50% rD-PD, DWC + 75% rD-PD, DWC + 25% rD-CD, DWC + 50% rD-CD, DWC + 75% rD-CD. Growth parameters and yield of okra were determined. The average temperature in the rearing environment was 27.6 ± 1.5˚C and pH 7.9 ± 1.1. After six (06) months of rearing, C. gariepinus individuals reached an average weight of 850.12 ± 1.3 g and an average height of 52.44 ± 1.1 cm. The daily weight gain and specific growth rates over this period were 3.9 g per day and 2.8% per day, respectively. The treatment T1 (rW + Dr-NPK) gave the highest mean collar diameter and mean plant height with 2.3 ± 0.9 cm and 61.6 ± 32 cm, respectively. In T4 (DWC), the mean height of plants was 38.8 ± 23.5 cm and mean collar diameter 1.4 ± 0.8 cm. The growth performance in T4 was comparable to that of rD-CD (T3), but different from rD-NPK (T1) and rD-PD (T2). The highest average number, average weight, average length and average diameter of fruits were noted in treatments T13 (rW + rD-75%CD) and T7 (DWC + 75% rD-NPK). The best yields were noted in T1 (rW +

关键词： Integrated Aquaculture Drained Water Fertilization C. gariepinus Okra

Epidemiological and Hemato-Biochemical Profiles of Diabetic Patients at the Diabetology, Endocrinology, and Metabolic Diseases Department of the Alpha Oumar Diallo regional Hospital, Kindia (republic of Guinea)

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Journal of Diabetes Mellitus 2024年第2期14卷 108-121页

作者： Fatoumata Bah Cé Camara Ousmane Sangare Elhadji Saidou Balde Karamo Toure Taliby Dos Camara Mariama Kourouma César Hagassou Biology Laboratory Department of Biology Faculty of Sciences Gamal Abdel Nasser University Conakry (Commune of Dixinn) Guinea Higher School of Tourism and Hospitality of Guinea Conakry Guinea Faculty of Pharmaceutical and Medical Sciences Gamal Abdel Nasser University Conakry Guinea

This study aims to enhance the healthcare services for diabetic patients in the administrative region of Kindia by suggesting dietary interventions to assist diabetics in better managing their condition. Conducted over a period of six months, from February 18 to July 18, 2021, this prospective and descriptive cross-sectional study involved 220 diabetic patients. Among these, 48 patients (22%) maintained balanced glucose levels (2 g/l). Positive glycosuria was observed in 54% of the patients, whereas 46% demonstrated normal glycosuria. An analysis of urinary parameters revealed that 15% of the patients had abnormal Ketone Bodies. Normal HbA1c levels (9%) HbA1c levels. Hematological assessments indicated significant variation: 56% of the patients had low hemoglobin levels, 4% suffered from hyper-eosinophilia, and 1% each from hyper-basophilia and hyper-hemoglobinemia. The anemic profile was characterized as mild anemia in 75%, moderate anemia in 20%, and severe anemia in 5%. Furthermore, 25% of patients were affected by Microcytic anemia and 75% by Normocytic anemia. Demographically, women constituted 65% of the study group compared to 35% of men. The most represented age bracket was 41 to 60 years, accounting for 52% of the patients, while those between 61 and 80 years comprised 36%. Every district in Kindia was impacted by diabetes.

关键词： Epidemiology Diabetes Glucose Levels Glycosuria Metabolic Disorders Kindia

Optimized Adsorption of Small and Medium Molecules by a Biosorbent Based on Hevea Hulls

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Journal of Materials Science and Chemical Engineering 2024年第9期12卷 69-83页

作者： Djedjess Essoh Jules César Meledje Yapo Hermann Aristide Yapi David Léonce Kouadio Djamatchè Paul Valéry Akesse Kolo Yeo Laboratoire des Sciences Physiques Fondamentales et appliques Ecole Normale Suprieure dAbidjan Abidjan Cte dIvoire Mathmatiques physiques Chimie Physique UFR Environnement Universit Jean Lorougnon Gud Daloa Cte dIvoire

In the context of the recovery of agricultural waste, many researches have focused on the preparation of adsorbents from natural waste from fruit trees, egg shells, palm waste or sawdust. This work aims to optimize the preparation of a biosorbent from rubber hulls by studying its ability to adsorb small and medium molecules. The influence of parameters such as drying temperature (X1), particle size (X2), stirring time (X3) and sodium hypochloride mass (X4) was studied. The results indicate that the model used for biosorbent optimization on methylene blue and iodine index is significant. In addition, this model has greater adsorption capabilities on small molecules than with large molecules. Statistical analysis of the data shows that temperature is the most influential factor in the adsorption of small molecules. On the other hand, particle size has a significant influence on the adsorption of large molecules. The optimum biosorbent preparation values are 1.0 for drying temperature (X1), −1.0 for biosorbent grain size (X2), 1.0 for stirring time (X3) and 1.0 for sodium hypochloride mass (X4).

关键词： Optimization Biosorbent Methylene Blue Index Iodine Index rubber Hulls

Analysis of the Quality of Physical and Chemical Parameters of Groundwater in Three Localities in the Sub-Prefecture of Zanzra (Ivory Coast)

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Journal of Materials Science and Chemical Engineering 2024年第4期12卷 1-17页

作者： Djedjess Essoh Jules-César Meledje Bi Irié Marc Gouli Drissa Ouattara Kra Vanh Eric-Simon Zran Adjourma Konate Albert Trokourey Laboratoire de Chimie des Eaux (LCE) de l’ Ecole Normale Sup&#233rieure d&#8217Abidjan Abidjan C&#244te d&#8217Ivoire Laboratoire de Constitution et ré action de la Mati&#232re (LCRM) &#224 l&#8217UFR SSMT-Universit&#233 F&#233lix Houphou&#235t-Boigny (UFHB) de Cocody Abidjan C&#244te d&#8217Ivoire

The availability of groundwater of acceptable quality has become a difficult challenge to meet in many countries, particularly Côte d’Ivoire. The State of Côte d’Ivoire and rural populations are building hydraulic infrastructure for this purpose. However, the quality of water coming from these infrastructures remains to be determined. This study therefore aims to analyze certain physicochemical parameters of the groundwater of Gloazra, Kouezra and Trahonfla. These are temperature, pH, electrical conductivity, TDS, salinity level, hardness, alkalinity, chloride content and bicarbonate. To determine the pH, electrical conductivity, temperature, TDS, and salinity rate, an electrochemical analysis was carried out. The titrimetric analysis made it possible to determine the chloride and bicarbonate content, alkalinity, and hardness. The results indicate that the studied groundwater is soft and acidic with good mineralization. This water does not present a health hazard to consumers but can affect hydraulic equipment and household containers.

关键词： Ivory Coast Gloazra Trahonfla Kouezra Physicochemical Parameters Water WHO Standards

Evaluation of the Antibacterial and Antifungal Capacity of Nanoemulsions Loaded with Synthetic Chalcone Derivatives Di-Benzyl Cinnamaldehyde and Benzyl 4-Aminochalcone

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Journal of renewable Materials 2024年第2期12卷 285-304页

作者： Flavia Oliveira Monteiro da Silva Abreu Taysse Holanda Joice Farias do Nascimento Henety Nascimento Pinheiro rachel Menezes Castelo Hélcio Silva dos Santos Thais Benincá Patrícia da Silva Malheiros Júlio César Sousa Prado raquel de Oliveira Fontenelle Maria Madalena de Camargo Forte Natural Polymers Laboratory PPGCNState University of CearáFortaleza60.714.903Brazil Polymeric Materials Laboratory PPGE3MFederal University of Rio Grande do SulPorto Alegre91501-970Brazil Natural Product Chemistry Laboratory PPGCNState University of CearáFortaleza60.714.903Brazil Food Hygiene and Microbiology Laboratory PPGCTAFederal University of Rio Grande do SulPorto Alegre91501-970Brazil Microbiology Laboratory Medicine SchoolFederal University of CearáSobral62010-560Brazil

With the increase in antimicrobial resistance,it has become necessary to explore alternative approaches for combating and preventing ***-cinnamaldehyde(CNM)and Benzyl4-amino(B4AM)are bioactive compounds derived from chalcones but with restricted solubility in aqueous *** can enhance the solubility of compounds and can be a promising alternative in the development of novel antimicrobials,with reduced side effects and prolonged *** objective of this study was to evaluate the stability of oil-in-water nanoemulsions loaded with two distinct types of chalcones at two different dosages,to propose a stable formulation with antimicrobial *** showed that nanoemulsions presented high encapsulation efficiency,low polydispersity index(PDI)and particle size below 200 nm,indicating that emulsification was a suitable method for nanoemulsion *** with higher dosages exhibited significant antimicrobial effects when compared to free chalcones and positive ***,B4AM nanoemulsions at higher dosages showed expressive activity against Salmonella minnesota,with a 420%greater inhibitory response compared to the free form and showing equivalence to the positive *** nanoemulsions showed excellent inhibitory activity at the highest dosage,equivalent to the positive control against *** and Staphylococcus *** greater number of conjugated bonds in CNM increased the antimicrobial activity in comparison with B4AM,and the formation of nanometric domains enhanced the bioavailability,being a promising alternative for antimicrobial applications.

关键词： Polysaccharide nanoemulsions S.aureus S.minnesota chalcones alginate