期刊文献+
共找到2,813篇文章
< 1 2 141 >
每页显示 20 50 100
Environmental Justice,Planning and Oil and Gas Pipelines in the Niger Delta Region of Nigeria
1
作者 Friday A.Ogwu 《Journal of Traffic and Transportation Engineering》 2025年第1期28-35,共8页
This paper analyses the impact of oil and gas pipelines on the environment and settlements from the perspective of environmental justice,using a case study of the oil-producing communities in the Niger Delta region of... This paper analyses the impact of oil and gas pipelines on the environment and settlements from the perspective of environmental justice,using a case study of the oil-producing communities in the Niger Delta region of Nigeria.The paper mobilises theories of environmental justice to support an in-depth empirical analysis of the development and management of oil and gas pipelines in the region.The empirical evidence equally suggests that the lack of community involvement and appropriate recognition of some groups of stakeholders in the management of the oil and gas pipeline project is strongly related to the incidence of pipeline impacts on the communities[1].The paper advocates a new approach,based on the core principles of environmental justice that promotes inclusion of the necessary stakeholders,including the physical planners,and would incorporate local knowledge and experience into the environmental management of the region in a way to protect the environment and people from the impacts of the pipeline[2]. 展开更多
关键词 Environmental justice PLANNING oil and gas pipelines niger Delta nigerIA
在线阅读 下载PDF
释硅真菌Aspergillus niger CA-5的分离鉴定及抗逆促生特性
2
作者 习彦花 林勇 +4 位作者 李俊磊 吕亚天 孙立博 魏帅强 程辉彩 《环境保护科学》 2025年第1期131-138,共8页
文章采用选择性培养基从河北典型铁尾矿区土壤中挖掘优良菌株资源,通过对溶硅能力的定性筛选和定量测定获得一株高效的释硅真菌CA-5,经培养性状、形态特征及ITS分子生物学鉴定为黑曲霉Aspergillus niger,同时对其生态适应性及相关促生... 文章采用选择性培养基从河北典型铁尾矿区土壤中挖掘优良菌株资源,通过对溶硅能力的定性筛选和定量测定获得一株高效的释硅真菌CA-5,经培养性状、形态特征及ITS分子生物学鉴定为黑曲霉Aspergillus niger,同时对其生态适应性及相关促生能力进行了测定,并通过室内盆栽验证该菌对小白菜幼苗的促生效果。结果表明:该株高效释硅真菌CA-5对富硅铁尾矿的释硅量可达30.03 mg/L;对盐、酸碱、干旱等逆境具有较好的生态适应性,同时具有溶磷解钾、分泌吲哚-3-乙酸(indole-3-acetic acid,IAA)及铁载体等促生能力。结果表明,接种适宜浓度的CA-5显著促进了植物幼苗株高、鲜质量和干质量的增加,显著提高小白菜叶片叶绿素相对含量(Soil and Plant Analyzer Development,SPAD),明显改善植株的倾倒现象。该株高效释硅黑曲霉CA-5具有作为释硅微生物菌剂的开发潜力,可为开发新型生物硅肥、助力尾矿绿色生态修复提供新的途径。 展开更多
关键词 释硅真菌 筛选鉴定 黑曲霉 抗逆性 促生
在线阅读 下载PDF
Vulnerability of Farms to Climate Variability and Change, and Adaptation Actions in the Tillabéry Department, Niger
3
作者 Idrissa Saidou Mahamadou Yacouba Ali Razinatou Soumana Boubacar 《Journal of Agricultural Chemistry and Environment》 2025年第1期56-73,共18页
In Niger, farms have been facing negative effects of climate change for several decades. The objective of this work is to assess the vulnerability of farms in Tillabery department by proposing an adaptation approach. ... In Niger, farms have been facing negative effects of climate change for several decades. The objective of this work is to assess the vulnerability of farms in Tillabery department by proposing an adaptation approach. A five-step method and descriptive analysis were used on a sample of 250 farmers. The degree of damage caused by pests and crop diseases is significant, with respective proportions of 52.50% and 40.40%. It appears that the main climate risk factors for vulnerability are droughts, floods, soil degradation, and pest invasions. Additionally, the average level of exposure to agricultural operations is very high, with an index of 0.6. The sensitivity index remained constant in the range of 0.3 to 0.6 and is significant (reaching an index of 0.8). However, 61.2% of farms have a medium level of vulnerability and 33.3% have a high vulnerability to the effects of climate change. Nonetheless, a concerning trend regarding the vulnerability of farms has been observed. To assist policymakers and development actors in improving the vulnerability level of these production units, four phases of action are proposed: a diagnostic phase, evaluation, estimation of adaptation needs, implementation, and proper monitoring of actions. 展开更多
关键词 VULNERABILITY Farms Climate Change Tillabery niger
在线阅读 下载PDF
Impact of Sesbania pachycarpa dc. (Fabaceae) in Millet Culture [Pennisetum glaucum (L.) R. Br. (Poaceae)] in Eastern Southeast Niger
4
作者 Mahamane Adamou Toudou Daouda Abdoul Karim +7 位作者 Abdourazak Alio Moussa Adamou Ibrahim Maman Laouali Toudou Abdoul Karim Adamou Aboubacar Kolafane Inoussa Maman Maarouhi Douma Soumana Bakasso Yacoubou Mahamane Ali 《American Journal of Plant Sciences》 2025年第1期146-154,共9页
Millet [Pennisetum glaucum (L.) R. Br. (Poaceae)] is one of the most widely consumed crops in Niger. Its production, despite the efforts of farmers, is confronted with weed problems, in particular Sesbania pachycarpa ... Millet [Pennisetum glaucum (L.) R. Br. (Poaceae)] is one of the most widely consumed crops in Niger. Its production, despite the efforts of farmers, is confronted with weed problems, in particular Sesbania pachycarpa DC. (Fabaceae). The aim of the present study in this area is to assess the impact of Sesbania pachycarpa on millet growth and yield. To achieve this objective, a completely randomized Fisher block design of twenty-four elementary plots was set up with four replications. The data collected were millet plant heights and plot yields. The data collected were subjected to analysis of variance and Duncan’s test at the 5% threshold for comparisons of mean heights and yields with the control kept clean from sowing to millet harvesting. The results showed the sensitivity of millet plants to Sesbania pachycarpa. The results revealed that the threshold density for damage could be estimated at 6 Sesbania pachycarpa plants/m2 and the critical interference period at the fourth week after sowing. This study showed that the presence of Sesbania pachycarpa influences millet yield. Indeed, the best yields were obtained in plots without Sesbania pachycarpa. Millet yield decreased with increasing Sesbania pachycarpa density. The average percentage yield reduction was 36.79%, with a minimum of 21.25% and a maximum of 80%. The findings of this study complete the efforts of developing weed control techniques in pearl millet fields densely populated with Sesbania pachycarpa. 展开更多
关键词 IMPACT Sesbania pachycarpa Yield MILLET niger
在线阅读 下载PDF
On-Station Bioefficacy of Neem Seed Extract and Beauveria bassiana 115 for Managing Major Insect Pests of Cowpea in the Sahelian Region of Maradi, Niger
5
作者 Laouali Amadou Souleymane Laminou +5 位作者 Ousseina Abdoulaye Mahaman Nassirou Oumarou Roufai Yarifou Nana Hadiza Issa Labo Ramatou Bargui Abdoulaye Ibrahim Boukari Baoua 《Agricultural Sciences》 2025年第1期1-12,共12页
Cowpea, Vigna unguiculata L. Walp, is an important food grain legume in Niger facing production losses due to insect pests. This study aims to determine the efficiency of non-chemical methods for managing these pests.... Cowpea, Vigna unguiculata L. Walp, is an important food grain legume in Niger facing production losses due to insect pests. This study aims to determine the efficiency of non-chemical methods for managing these pests. A trial was conducted during the 2020 and 2022 cropping seasons at the INRAN station in the Maradi region. A Fischer experimental design with 6 repetitions was used to compare 4 treatments: synthetic chemical pesticide;the entomopathogenic fungus Beauveria bassiana;aqueous extracts of neem seeds, and control. Observations were carried out every three days. The cowpea pod-sucking bug, pod borer, and thrips were the main insect pests recorded. In terms of effectiveness, the synthetic pesticide was the best treatment. It reduced insect pest densities by 71.35% to 90.40% in 2020 and by 35.11% to 42.13% in 2022. Grain yields varied between treatments. Neem seed extract followed the synthetic pesticide and significantly reduced insect infestations in both years. The synthetic pesticide and neem seed extract resulted in yields 3 to 5 times higher than the control treatment in 2020. By contrast, B. bassiana 115 and neem seed extract produced similar yields in 2022. Therefore, the results of this study showed that B. bassiana 115 and neem seed extract have insecticidal potential and could be used as an ecological alternative for managing cowpea insect pests in the Sahel. 展开更多
关键词 Vigna unguiculata BIOPESTICIDE COWPEA Insect Pest niger
在线阅读 下载PDF
From Crisis to Recovery: Addressing Hydrocarbon Pollution in Niger Delta Soils Treated with Pleurotus ostreatus and Eisenia fitida
6
作者 Gift Evans Fubara Dokuboba Amachree +7 位作者 Ilemi Jennifer Soberekon Esther Omone Akhigbe Digha Opaminola Nicholas Akayinaboderi Augustus Eli Enyinnaya Okoro Igoniama Esau Gamage Ayibatonyo Markson Nathaniel Morufu Olalekan Raimi 《Open Journal of Yangtze Oil and Gas》 2025年第1期1-29,共29页
Rationale: The contamination of soil with crude oil poses significant environmental and ecological threats. Bioremediation, particularly through the use of organisms like Pleurotus ostreatus (mushroom) and Eisenia fet... Rationale: The contamination of soil with crude oil poses significant environmental and ecological threats. Bioremediation, particularly through the use of organisms like Pleurotus ostreatus (mushroom) and Eisenia fetida (earthworm), has emerged as a promising approach to mitigate crude oil pollution. Understanding the effectiveness of these organisms in reducing hydrocarbon levels in contaminated soil is crucial for devising sustainable remediation strategies. Objectives: This study aimed to evaluate the efficacy of Pleurotus ostreatus and Eisenia fetida in remediating crude oil-polluted soil. Specifically, it sought to assess the hydrocarbon profiles in soil treated with these organisms across varying concentrations of crude oil pollution. Method: Crude oil concentration levels ranging from 0% to 10% were applied to soil samples alongside control treatments, including soil only, soil with earthworms, and soil with mushrooms. Each treatment was replicated five times using a randomized complete block design. Standard methods were employed to determine the hydrocarbon contents of the soil. Results: The results indicated a significant increase (P Pleurotus ostreatus and Eisenia fetida exhibited noteworthy reductions in these hydrocarbon levels. At the three-month mark, mushrooms demonstrated a remarkable ability to reduce hydrocarbon content by 70% - 90% compared to the pollution treatment. In contrast, earthworms exhibited minimal potential for hydrocarbon reduction, particularly at both three and six-month intervals. For instance, TOC reduction reached a maximum of 96% with mushroom treatment and 85% with earthworm treatment at 5% crude oil pollution over six months. Conclusion: The findings highlight the effectiveness of Pleurotus ostreatus in significantly reducing hydrocarbon levels in crude oil-polluted soil compared to Eisenia fetida. Mushroom-treated soils consistently exhibited substantial reductions in TOC, TPH, TOG, PAH, and THC over the study period, suggesting their potential as a viable bioremediation agent. In contrast, while earthworms showed some capability in reducing hydrocarbon content, their effectiveness was comparatively limited. Recommendation: Based on the results, it is recommended to utilize Pleurotus ostreatus for the bioremediation of crude oil-polluted soils. Further research could explore optimizing remediation protocols involving mushroom-based treatments for enhanced efficiency. Statement of Significance: This study contributes valuable insights into the application of bioremediation techniques for mitigating crude oil contamination in soil. The demonstrated efficacy of Pleurotus ostreatus underscores its potential as a sustainable and eco-friendly solution for remediating hydrocarbon-polluted environments, offering a promising avenue for environmental restoration and conservation efforts. 展开更多
关键词 HYDROCARBON Crude Oil Soil Pollution REMEDIATION Pleurotus ostreatus Eisenia fitida WETLAND Core niger Delta
在线阅读 下载PDF
Effect of Neem Seed-Based Biopesticides and Hygienized Human Urine (HHU) on the Main Insect Pests of Cowpea [Vigna unguiculata (L.) Walp.] on Station and in Rural Environment of Niger
7
作者 Laouali Amadou Ousseina Abdoulaye +7 位作者 Ibrahim Boukari Baoua Abdou Sani Souleymane Mahaman Nassirou Oumarou Roufai Yarifou Laouali Ibrahim Souleymane Lamine Ali Maman Aminou Ouorou Kobi Douro Kpindou 《American Journal of Plant Sciences》 2025年第2期195-215,共21页
Cowpea, Vigna unguiculata (L.) Walp. is an economically important seed legume that helps combat food and nutrition insecurity in the Sahel, particularly Niger. However, its yield remains low due to insect pest attacks... Cowpea, Vigna unguiculata (L.) Walp. is an economically important seed legume that helps combat food and nutrition insecurity in the Sahel, particularly Niger. However, its yield remains low due to insect pest attacks. This study was conducted at a station and in seven villages in the Maradi and Tahoua regions. It aimed to test the effectiveness of neem seed biopesticides [Azadirachta indica A. Juss] and sanitized human urine for integrated insect pest management. The cowpea variety UAM09 1055-6 was used for the experiments. The experimental trial was a Fisher block design consisting of five treatments: neem oil, neem seed extract (NSE), hygienized human urine (HHU), chemical pesticide, and a control, replicated five times at the station and twice in farmers’ environments. The study shows that Megalurothrips sjostedti Trybom, Clavigralla tomentosicollis Stål and Maruca vitrata Fabricius are the main insect pests. Plots treated with synthetic pesticides were the least infested by C. tomentosicollis. They were followed by neem seed extract and HHU treatments, which recorded an infestation level of 2.44 and 20.5 times lower than controls at the station and in farming environments. The density of thrips was 1.06 to 32.6 times lower in treated plots compared to controls. The proportion of pods damaged by M. vitrata was 1.95, 2.55, and 2.77 times lower in plots treated with HHU, NSE, and synthetic pesticide, respectively, compared to controls. Grain yields were 1.80 and 2.62 times higher in UHH and NSE treatments compared to control plots, both at the station and in farmers’ environments. A yield increase of 44.58% and 61.92% was noted for these treatments at the station and in farmers’ environments, respectively. These results may promote the dissemination of NSE and HHU biopesticide technologies in rural areas as an alternative method for integrated pest management of cowpeas. 展开更多
关键词 COWPEAS Hyginized Human Urine NEEM Insect Pests niger
在线阅读 下载PDF
Acute Bronchiolitis about 535 Cases at Zinder National Hospital, Niger
8
作者 Georges Thomas Ibrahim Doutchi Mahamadou +4 位作者 Hassane Maman Laoul Hamza Mahaman Nafissa Garba Moumouni Samaila Aboubacar Kamaye Moumouni 《Open Journal of Pediatrics》 2025年第1期130-140,共11页
Introduction: Lower respiratory infections in general, and acute bronchiolitis in particular, represent a major cause of morbidity in children in Niger. The aim of this study was to investigate the epidemiological, di... Introduction: Lower respiratory infections in general, and acute bronchiolitis in particular, represent a major cause of morbidity in children in Niger. The aim of this study was to investigate the epidemiological, diagnostic and therapeutic features of acute bronchiolitis in infants in the Pediatrics A department of the National Hospital in Zinder. Patients and Methods: This was a descriptive, cross-sectional study with prospective data collection conducted from April 1 to May 31, 2024. All infants aged 0 to 24 months hospitalized with acute bronchiolitis in the pediatric ward A of Zinder National Hospital were included in the study. Epidemiological, diagnostic and therapeutic aspects were the characteristics studied. Data analysis was performed using Epi info 7 software. Results: During the study period, acute bronchiolitis accounted for 51% of hospitalizations, and infants aged 3 - 11 months were the most affected (52.90%). The sex ratio was 1.6. The average age of patients was 10.40 ± 6.91 months, with extremes of 1 and 24 months. 98.50% of patients came from urban areas, and the socioeconomic level of families was average in 47.49% of cases. Mixed breastfeeding was practiced in 59.63% of cases. Average hospital admission time was 4.22 days. The main clinical signs were cough (43.18%), rhinorrhea (70.85%), ronchi (35.33%), crepitating rales (26.54%), sibilant rales (24.11%), signs of struggle (14.02%) and polypnea (70.85%). Paraclinical findings included chest distension, hyperleukocytosis and anemia, with 47.48%, 55.14% and 78.31% respectively. Therapeutically, nebulization was used in 93.08% of cases, respiratory physiotherapy (41.34%), corticosteroid therapy (34.08%), antibiotic therapy (21.50%), oxygen therapy (20.11%) and antipyretics (4.68%) were prescribed. Progression was favorable in 93.08% of patients, with a case-fatality rate of 1.12%. Conclusion: With its high frequency, acute bronchiolitis is a public health problem. Boys were the most affected by the condition, and the predominant age group was 3 to 11 months. Management was essentially based on nebulization and physiotherapy. 展开更多
关键词 Acute Bronchiolitis INFANT Zinder niger
暂未订购
Evaluation of Two Methods of Production and Release of the Parasitoid Habrobracon hebetor Say (Hymenoptera: Braconidae) for the Control of Pearl Millet Head Miner Heliocheilus albipunctella (de Joannis) (Lepidoptera: Noctuidae) in Maradi (Niger)
9
作者 Laouali Amadou Mahaman Nassirou Oumarou +5 位作者 Ousseina Abdoulaye Souleymane Laminou Issa Yacouba Ibrahim Baoua Malick N. Ba Rangaswamy Muniappan 《Advances in Entomology》 2025年第1期126-138,共13页
Pearl millet, Pennisetum glaucum (Leeke) R. Br, is the main cereal crop in Niger. This crop is seriously attacked by the millet Head miner (MHM), Heliocheilus albipunctella (de Joannis) (Lepidoptera, Noctuidae) causin... Pearl millet, Pennisetum glaucum (Leeke) R. Br, is the main cereal crop in Niger. This crop is seriously attacked by the millet Head miner (MHM), Heliocheilus albipunctella (de Joannis) (Lepidoptera, Noctuidae) causing significant yield losses. This study to optimize biological control of this pest was carried out in Niger in the laboratory and in a farming environment. In the laboratory, the larval paralysis and emergence of the parasitoid Habrobracon hebetor Say (Hymenoptera: Braconidae) were compared between release jute bags, plastic boxes and cardboard boxes. In a farming environment, direct releases were carried out with plastic boxes and releases with jute bags in 12 villages of the Maradi region during the cropping seasons of 2021 and 2022. The results indicated that 25 larvae of Corcyra cephalonica Stainton (Lepidoptera: Pyralidae) in the boxes were all paralyzed by 2 females of H. hebetor within 7 hours 30 minutes. The emergence of adults began on the 7th day after the beginning of the experiment for a period of two weeks and three weeks respectively in the boxes and jute bags. The production varied from 107.08 to 110.17 parasitoids and was comparable between the Jute bags, plastic boxes and cardboard boxes. In Farmers’ fields, the parasitoid release with the two methods caused the parasitism rates that varied from 64.32 to 66.52% depending on the year but in 2022 the rate of parasitism was higher in the fields with direct releases using plastic boxes (72.66%) compared to those released with jute bags (56.35%). Plastic boxes and cardboard boxes can be used for the production of the H. hebetor parasitoids. These results can be recommended to the cottage industries in the Sahel in order to improve the production and release methods of H. hebetor and make them more adapted to farmers’ fields. 展开更多
关键词 Biological Control Parasitoid Release Hebrobracon hebetor Heliocheilus albipunctella niger
在线阅读 下载PDF
Petroleum system,filling history and age appraisal of source rocks of the Niger Delta Basin:Fingerprinting of pentacyclic triterpenoids
10
作者 Timothy Chibuike Anyanwu Bassey Offiong Ekpo 《Energy Geoscience》 2025年第2期331-341,共11页
Gas chromatography-mass spectrometry(GC-MS)was used to analyze the pentacyclic triterpenoid distributions,specifically hopane and oleanane fingerprints,in 24 crude oil samples from the Niger Delta depobelts,with the a... Gas chromatography-mass spectrometry(GC-MS)was used to analyze the pentacyclic triterpenoid distributions,specifically hopane and oleanane fingerprints,in 24 crude oil samples from the Niger Delta depobelts,with the aim of defining the petroleum system,filling history,and the age of source rock producing these oils.The results indicate that the Niger Delta oils belong to a single fluvio-deltaic petroleum system,reflecting similar source organic facies and depositional environments.Geochemical parameters,including C29/C30hopane ratios,oleanane index,Ts/Tm,(Ts/(Ts+Tm)),moretane/C30hopane ratios,and C3222S/(22S+22R)ratios,suggest oxic conditions during source rock deposition and thermal maturity of the oils.The presence of terrigenous organic matter and complex filling history are also evident and influenced by multiple phases of sedimentation,and petroleum generation.A comparative plot of geologic time(Paleogene-Neogene age)and oleanane percentage composition show that the crude oils are constrained to the chronostratigraphic ages of their respective depobelts,demonstrating the potential of oleanane-derived parameters for relative dating of hydrocarbon sources,complementing traditional index fossil methods. 展开更多
关键词 OLEANANE Petroleum system Depositional history MATURITY Depobelts niger delta
在线阅读 下载PDF
Yeast diversity and screening of biocontrol Yarrawia lipolitica against ochratoxin A biosynthesis by Aspergillus niger in Panxian ham
11
作者 Yanhong Chen Yuanshan Chen +1 位作者 Qiujin Zhu Jing Wan 《Food Science and Human Wellness》 2025年第8期3191-3202,共12页
Nature fermented dry-cured hams may be contaminated by ochratoxin A(OTA)due to the colonization of OTA-producing fungi.Yeast plays essential roles in the formation of the special flavor of ham as well as the potential... Nature fermented dry-cured hams may be contaminated by ochratoxin A(OTA)due to the colonization of OTA-producing fungi.Yeast plays essential roles in the formation of the special flavor of ham as well as the potential to retard OTA biosynthesis.In this study,the yeast diversity of Panxian hams fermented from 1 year to 2 years was investigated,revealing a total of 9 yeast genera.The dominant genus switched from Debaryomyces hansenii to Yamadazyma triangularis,while the yeast diversity increased with the prolongation of the fermentation period.Notably,Yarrawia lipolitica GZPX-3Y-1 was identified as a biocontrol yeast strain that can effectively inhibit the OTA biosynthesis up to 82%in OTA-producing modeling media and 55%in ham media when cocultivated with a previously identified OTA producing fungi from Panxian ham,specifically Aspergillus niger A-8.The double-plate methods experiment unveiled that Y.lipolitica GZPX-3Y-1 can only inhibit the growth of A.niger A-8 under the anoxic conditions.Characteristics of Y.lipolitica GZPX-3Y-1 were explored,showing its ability to grow at wide range of temperature(18-33℃)and pH levels(pH 3-12).Additionally,it exhibited tolerance to high salt conditions(8%)and demonstrated lipolysis ability without hemolytic ability.These findings indicate the great potential of Y.lipolitica GZPX-3Y-1 to be applied in the fermentation of Panxian ham as a biocontrol strain. 展开更多
关键词 Panxian ham Ochratoxin A Aspergillus niger Yarrawia lipolitica
在线阅读 下载PDF
Investigation the Effect of Exposure Aspergillus niger Isolate to the UV Radiation on Its Superphosphate Fertilizer Dissolving Efficiency in Calcareous Soil
12
作者 Zainab K.Hasan Nawal I.Ashwer Hasan N.Habib 《Journal of Environmental & Earth Sciences》 2025年第1期205-213,共9页
A laboratory experiment was conducted to demonstrate the importance of improving the efficiency of six isolates of Aspergillus niger fungi.Four isolates were exposed to UV-rays radiation at a distance of 30 cm,a wavel... A laboratory experiment was conducted to demonstrate the importance of improving the efficiency of six isolates of Aspergillus niger fungi.Four isolates were exposed to UV-rays radiation at a distance of 30 cm,a wavelength of 254–255 nm during M15,M30,and M45 minutes.Exposure periods,both of wild(no UV-rays exposure)and no A.niger(C)as controls,all six isolates were identified molecularly by polymerase chain reaction technique extracted DNA of A.niger was analyzed to ensure gene completion through multiple sequence alignment by bioinformatic programs to study the improvement of dissolving efficiency of mutant and wild A.niger.They were incubated after the addition of superphosphate fertilizer(47%P2O5)at 90 mg P kg–1 applied to soil with controls(no A.niger or no superphosphate)for I,II,III,and IV weeks of incubation periods at 28±1°C.In addition,the DNA extraction and purification by NanoDrop of Thermo Scientific-200 A280/A260 ratio was 2.01 and confirmed that the sequences of nitrogenous bases by the method of multiple sequence alignment(MSA)as compared to the reference sequence of A.niger recorded in the gene bank under the accession number LC632396.Results proved that the M30 minutes exposure UV-rays radiation period was the superior dose when mutant Aspergillus niger obtained the highest amount of dissolved phosphate,reducing soil-pH with maximum biomass of A.niger during the M30 isolate during the third week(III). 展开更多
关键词 A.niger MUTATION PCR UV-Rays Radiation
暂未订购
Seismic and petrophysical data analysis for geological interpretation and subsurface modeling of Keva Field,onshore Niger Delta,Nigeria
13
作者 Kembou Tsobin Evans Olawale Olakunle Osinowo +4 位作者 Wasiu Odufisan Bashir AKoledoye Yusuf Odusanwo Tobechukwu Oluchukwu Ude-Akpeh Glory Yenchek Tiele 《Energy Geoscience》 2025年第2期86-99,共14页
This study integrates seismic and petrophysical data to evaluate the subsurface geology of the Keva Field,located onshore in the Niger Delta,with the objective of constructing a 3D geological model and estimating the ... This study integrates seismic and petrophysical data to evaluate the subsurface geology of the Keva Field,located onshore in the Niger Delta,with the objective of constructing a 3D geological model and estimating the recoverable hydrocarbon volumes.Seismic lines and well log data from six wells—KV-2,KV-3,KV-4,KV-5,KV-6,and KV-7—were utilized for the interpretation.The seismic profiles revealed that the KV-4 well is the only well drilled on the up-thrown side of a significant horst fault block,bounded by four major normal faults,while all the other wells penetrated the downthrown side.Petrophysical analysis identified three key reservoirs,C500,D200,and E900,which exhibit excellent reservoir quality with high net-to-gross ratios,good porosity,and high hydrocarbon saturation.The identified depositional environments are tidal-and fluvial-dominated shoreface settings,with sheet sands deposited in distributary splay systems.The C500,D200,and E900 reservoirs have Gas Initially in Place(GIIP)values of 156.37,28.44,and 27.89 BSCF,respectively,with corresponding Estimated Ultimate Recovery(EUR)values of 104.77,19.06,and 18.69 BSCF,respectively.The Stock Tank Original Oil in Place(STOOIP)values are 24.43,91.29,and 86.41 MMSTB,with EURs of 7.32,27.4,and 25.92 MMSTB,respectively.The combined GIIP is 212.72 BSCF with EUR of 142.52 BSCF,while the total STOOIP is 202.13 MMSTB with a recoverable volume of 60.64 MMSTB.The reservoirs present an average porosity of 22.62%,with gas saturation of 84.66%and oil saturation of 73%.The evaluated reservoir qualities suggest high potential for optimized hydrocarbon production. 展开更多
关键词 POROSITY PERMEABILITY Hydrocarbon saturation 3D geological modeling Keva field niger delta
在线阅读 下载PDF
From Oil to Health: Groundwater Quality and Its Potential Health Effects in Mgbede Oil Fields of South-South Nigeria
14
作者 Ijeoma Catherine Clinton-Ezekwe Morufu Olalekan Raimi +2 位作者 Ifeanyichukwu Clinton Ezekwe Ikenna Charles Osu Best Ordinioha 《Open Journal of Yangtze Oil and Gas》 2024年第4期95-118,共24页
Rationale: The quality of groundwater in the Mgbede Oil Fields of South-South Nigeria has raised significant concerns due to the risk of contamination from industrial activities, especially gas flaring. Evaluating the... Rationale: The quality of groundwater in the Mgbede Oil Fields of South-South Nigeria has raised significant concerns due to the risk of contamination from industrial activities, especially gas flaring. Evaluating the effects of these operations on groundwater quality is essential for safeguarding the health and well-being of local communities, as well as protecting the environment. Objective: This study aimed to evaluate the quality of groundwater in the Mgbede Oil Fields, specifically examining whether the water meets international drinking water standards and identifying any contaminants present due to gas flaring. Method: Purposeful selection of water sampling points was employed to ensure the objectives of the study were met. Groundwater samples were collected from various locations within the Mgbede Oil Fields and analyzed for key quality parameters, including pH, manganese, and turbidity, among others. Results: The analysis revealed that while most groundwater samples were within acceptable international drinking water limits, there were notable exceptions. pH levels ranged from 5.17 to 6.16, manganese concentrations from 0.001 to 0.136 mg/L, and turbidity levels from 0.00 to 825 mg/L. All sampled locations exhibited traces of manganese and high acidity, indicating particulate pollution likely resulting from gas flaring activities. Conclusions: The study concluded that the groundwater quality in the Mgbede Oil Fields is negatively impacted by continuous gas flaring. Contaminants such as manganese and increased acidity levels exceed acceptable international standards, posing potential risks to environmental health. Recommendations: To mitigate these risks, it is recommended that immediate measures should be taken to reduce gas flaring and its associated particulate emissions. Regular monitoring of groundwater quality should be implemented to track improvements and ensure compliance with international standards. Additionally, introducing filtration systems or alternative water sources could help protect the health of local communities. Significance Statement: This study underscores the significant impact of industrial activities, specifically gas flaring, on groundwater quality in the Mgbede Oil Fields. The findings highlight the urgent need for regulatory measures and continuous monitoring to safeguard environmental health and ensure the availability of safe drinking water. 展开更多
关键词 Groundwater Quality Mgbede Oil Fields Gas Flaring Water Contamination Environmental Health Industrial Pollution Toxic Metals Drinking Water Safety MANGANESE pH TURBIDITY niger Delta nigerIA
在线阅读 下载PDF
Effect of Aspergillus niger prolyl endopeptidase in patients with celiac disease on a long-term gluten-free diet 被引量:4
15
作者 Juan Pablo Stefanolo Verónica Segura +13 位作者 Martina Grizzuti Abel Heredia Isabel Comino Ana Florencia Costa Roberto Puebla María Paz Temprano Sonia Isabel Niveloni Gabriel de Diego María E Oregui Edgardo Gustavo Smecuol Mauricio C de Marzi Elena F Verdú Carolina Sousa Julio César Bai 《World Journal of Gastroenterology》 SCIE CAS 2024年第11期1545-1555,共11页
BACKGROUND The gluten-free diet(GFD)has limitations,and there is intense research in the development of adjuvant therapies.AIM To examine the effects of orally administered Aspergillus niger prolyl endopeptidase prote... BACKGROUND The gluten-free diet(GFD)has limitations,and there is intense research in the development of adjuvant therapies.AIM To examine the effects of orally administered Aspergillus niger prolyl endopeptidase protease(AN-PEP)on inadvertent gluten exposure and symptom prevention in adult celiac disease(CeD)patients following their usual GFD.METHODS This was an exploratory,double-blind,randomized,placebo-controlled trial that enrolled CeD patients on a long-term GFD.After a 4-wk run-in period,patients were randomized to 4 wk of two AN-PEP capsules(GliadinX;AVI Research,LLC,United States)at each of three meals per day or placebo.Outcome endpoints were:(1)Average weekly stool gluten immunogenic peptides(GIP)between the run-in and end of treatments and between AN-PEP and placebo;(2)celiac symptom index(CSI);(3)CeD-specific serology;and(4)quality of life.Stool samples were collected for GIP testing by ELISA every Tuesday and Friday during run-ins and treatments.RESULTS Forty patients were randomized for the intention-to-treat analysis,and three were excluded from the per-protocol assessment.Overall,628/640(98.1%)stool samples were collected.GIP was undetectable(<0.08μg/g)in 65.6%of samples,and no differences between treatment arms were detected.Only 0.5%of samples had GIP concentrations sufficiently high(>0.32μg/g)to potentially cause mucosal damage.Median GIP concentration in the AN-PEP arm was 44.7%lower than in the run-in period.One-third of patients exhibiting GIP>0.08μg/g during run-in had lower or undetectable GIP after AN-PEP treatment.Compared with the run-in period,the proportion of symptomatic patients(CSI>38)in the AN-PEP arm was significantly lower(P<0.03).AN-PEP did not result in changes in specific serologies.CONCLUSION This exploratory study conducted in a real-life setting revealed high adherence to the GFD.The AN-PEP treatment did not significantly reduce the overall GIP stool concentration.However,given the observation of a significantly lower prevalence of patients with severe symptoms in the AN-PEP arm,further clinical research is warranted. 展开更多
关键词 Celiac disease Aspergillus niger prolyl endoprotease Gluten immunogenic peptides TRIAL Symptoms Real-life trial
暂未订购
Land Use and Gully Dynamics in the Kourfa Watershed, Matankari (Southwest Niger) 被引量:1
16
作者 Bachirou Hamadou Younoussa Tahirou Hassane Yaou +4 位作者 Bouba Hassane Abass Kadade Sabou Abdoulkader Moussa Issaka Amadou Abdourhamane Toure Zibo Garba 《Journal of Geographic Information System》 2024年第4期306-320,共15页
The main consequences of climate change in the Sahel have been the metamorphosis of surface conditions. These metamorphoses have resulted in surface degradation, of which silting up of watersheds is the main phenomeno... The main consequences of climate change in the Sahel have been the metamorphosis of surface conditions. These metamorphoses have resulted in surface degradation, of which silting up of watersheds is the main phenomenon. The objective of this study is to assess the environmental trends of the Kourfa pond watershed. The study is based on diachronic mapping with Landsat satellite images and Google Earth images, over the period 1986 to 2021. The study reveals that vegetation (whose rate of regression doubled between 1986 and 2021) has decreased to the benefit of crop areas (whose rate of increase multiplied by 3.61 between 1986 and 2021). Bare soil and encrusted areas have also decreased, with regression rates almost double than those of 1986. In addition, the Kourfa waterholes have experienced two types of changes over 35 years: one progressive between 2011 and 2016 and the other regressive between 2001 and 2021 compared to 1986. The ravine network has been multiplied by a factor of 2.4, with density more than doubled and the connectivity of the hydrographic networks has risen from 2 to 4, with significant bank recession. This dynamic of the Kourfa pond is linked to the high drainage, the increasing complexity of the gully network and the erosion due to the retreat of the watershed banks, all of which contribute to the silting-up of the Kourfa watershed. 展开更多
关键词 Kourfa Pond DYNAMICS WATERSHED Dosso niger
在线阅读 下载PDF
Enzymatic Characterization of Pectinex XXL,a Pectinase Produced by Aspergillus niger,and Its Application in Fruit Juice Production
17
作者 ZHU Furong LIANG Xiaomei +3 位作者 WEI Zhifu LI Li HE Fengyuan CHENG Zhong 《现代食品科技》 CAS 北大核心 2024年第7期81-88,共8页
Pectinex XXL,a commercially prepared pectinase,was investigated for its potential application in the fruit juice industry.Polygalacturonic acid was used as the substrate for determining the enzymatic properties of Pec... Pectinex XXL,a commercially prepared pectinase,was investigated for its potential application in the fruit juice industry.Polygalacturonic acid was used as the substrate for determining the enzymatic properties of Pectinex XXL using the DNS method.According to the results,the optimal pH for Pectinex XXL activity was 4.5,and the enzyme was stable in the pH range of 3.0~4.5.The optimal pH and pH stability range are consistent with those of some tropical and subtropical fruits.The optimal temperature for Pectinex XXL activity was 60℃,and the enzyme remained stable after one hour in a water bath set at 40℃.Additionally,the enzymatic activity was not inhibited in the presence of 1 mmol/L of Na^(+),Mg^(2+),Ba^(2+),Co^(2+),Zn^(2+),and Fe^(2+),whereas it was slightly inhibited in the presence of 2 mmol/L of K^(+)and Fe^(2+)and partially inhibited in the presence of 1 and 2 mmol/L of Ca^(2+)and Mn^(2+),demonstrating its good stability in acids and excellent thermal catalytic performance.Based on the above experimental results,depectinization experiments were performed on plantain and cherry tomato juices using different amounts of Pectinex XXL.After one hour reaction with 16 U/mL of the enzyme,the yields of the plantain and cherry tomato juices were substantially increased by 119.03%and 15.97%,respectively,while their light transmittance was remarkably enhanced by 37.65%and 12.35%,respectively.Furthermore,the enzyme reduced the viscosity of the plantain and cherry tomato juices by 88.29%and 29.50%,respectively.The juice production experiments confirmed that this enzyme can significantly improve the yield and light transmittance of plantain juice,while effectively reducing its viscosity.These findings indicate the potential of Pectinex XXL in the industrial production of plantain juice. 展开更多
关键词 PLANTAIN cherry tomato fruit juice Aspergillus niger PECTINASE
在线阅读 下载PDF
Characterization of Depleted Hydrocarbon Reservoir AA-01 of KOKA Field in the Niger Delta Basin for Sustainable Sub-Sea Carbon Dioxide Storage
18
作者 Patrick A.Eigbe Olatunbosun O.Ajayi +1 位作者 Olabode T.Olakoyejo Adekunle O.Adelaja 《哈尔滨工程大学学报(英文版)》 CSCD 2024年第3期544-564,共21页
This study characterized the AA-01 depleted hydrocarbon reservoir in the KOKA field, Niger Delta, using a multidimensional approach. This investigation involved data validation analysis, evaluation of site suitability... This study characterized the AA-01 depleted hydrocarbon reservoir in the KOKA field, Niger Delta, using a multidimensional approach. This investigation involved data validation analysis, evaluation of site suitability for CO_(2) storage, and compositional simulation of hydrocarbon components. The primary objective was to determine the initial components and behavior of the hydrocarbon system required to optimize the injection of CO_(2) and accompanying impurities, establishing a robust basis for subsequent sequestration efforts in the six wells in the depleted KOKA AA-01 reservoir. The process, simulated using industry software such as ECLIPSE, PVTi, SCAL, and Petrel, included a compositional fluid analysis to confirm the pressure volume temperature(PVT) hydrocarbon phases and components. This involved performing a material balance on the quality of the measured data and matching the initial reservoir pressure with the supplied data source. The compositional PVT analysis adopted the Peng–Robinson equation of state to model fluid flow in porous media and estimate the necessary number of phases and components to describe the system accurately. Results from this investigation indicate that the KOKA AA-01 reservoir is suitable for CO_(2)sequestration. This conclusion is based on the reservoir's good quality, evidenced by an average porosity of 0.21 and permeability of 1 111.0 mD, a measured lithological depth of 9 300 ft, and characteristic reservoir – seal properties correlated from well logs. The study confirmed that volumetric behavior predictions are directly linked to compositional behavior predictions, which are essential during reservoir initialization and data quality checks. Additionally, it highlighted that a safe design for CO_(2) storage relies on accurately representing multiphase behaviour across wide-ranging pressure–temperature–composition conditions. 展开更多
关键词 Carbon capture CO_(2)sequestration Geological storage Geo-mechanical modeling Multiphase flow niger Delta
在线阅读 下载PDF
Aspergillus niger prolyl endopeptidase in celiac disease
19
作者 Marica Colella Concetta Cafiero Raffaele Palmirotta 《World Journal of Gastroenterology》 SCIE CAS 2024年第24期3044-3047,共4页
We comment here on the article by Stefanolo et al entitled“Effect of Aspergillus niger prolyl endopeptidase in patients with celiac disease on a long-term gluten-free diet”,published in the World Journal of Gastroen... We comment here on the article by Stefanolo et al entitled“Effect of Aspergillus niger prolyl endopeptidase in patients with celiac disease on a long-term gluten-free diet”,published in the World Journal of Gastroenterology.Celiac disease is a well-recognized systemic autoimmune disorder.In genetically susceptible people,the most evident damage is located in the small intestine,and is caused and worsened by the ingestion of gluten.For that reason,celiac patients adopt a gluten-free diet(GFD),but it has some limitations,and it does not prevent re-exposure to gluten.Research aims to develop adjuvant therapies,and one of the most studied alternatives is supplementation with Aspergillus niger prolyl endopeptidase protease(AN-PEP),which is able to degrade gluten in the stomach,reducing its concentration in the small intestine.The study found a high adherence to the GFD,but did not address AN-PEP as a gluten immunogenic peptide reducer,as it was only tested in patients following a GFD and not in gluten-exposing conditions.This study opens up new research perspectives in this area and shows that further study is needed to clarify the points that are still in doubt. 展开更多
关键词 Celiac disease Aspergillus niger prolyl endoprotease Gluten immunogenic peptides TRIAL Symptoms Real-life trial
暂未订购
Evaluation of formation susceptibility and sand production potential in an offshore field,Niger Delta Basin,Nigeria
20
作者 David O.Ubuara Yinka A.Olayinka +1 位作者 Godwin O.Emujakporue Geoffrey C.Soronnadi-Ononiwu 《Energy Geoscience》 EI 2024年第1期1-11,共11页
Wellbore instability and sand production are all common challenges in the Niger Delta oil province,resulting in high drilling and production cost as well as damage to oil facilities.The vulnerability of lithologic for... Wellbore instability and sand production are all common challenges in the Niger Delta oil province,resulting in high drilling and production cost as well as damage to oil facilities.The vulnerability of lithologic formations to wellbore instability and resultant sand production is investigated in the four delineated reservoirs of the“Areo”field,western part of Niger Delta Basin.The foundation for establishing the geomechanical properties in this study was a 1-dimensional mechanical earth model,using gamma ray(GR),density(RHOB),compressional slowness(DTC),and shear slowness(DTS)logs.Within the Areo oil field,two wells(well 001 and well 002)were correlated.The evaluated formations are still primarily composed of compacted shale and unconsolidated sandstone,with reservoir sand units exhibiting lower elastic and rock strength properties than shale units.High compressibility and porosity make sand more brittle,while low compressibility and porosity make shale stiffer due to high moduli.The maximum force that can be applied to a shale unit without causing it to fail is 17.23 MPa,which is the maximum average rock strength of the shale.It means that shale requires more vertical stress or pressure than sand does in order to deform it(15.06 MPa).The three sand prediction approaches used in the analysis of sand production predictions have cut-off values that are higher than the average values of the formations.The Schlumberger sand production index method(S/I)indicates that the reservoir has potential for sand influx in the two wells,with the average of the four reservoirs studied in wells 001 and 002 being 1.551012 psi and 1.141012 psi respectively.However,when a formation's sand production index is less than 1.241012 psi,as it is in this study,the formation is likely to produce sand.These findings support the notion that the defined sandstone units are highly unconsolidated and have a high potential for producing sands;therefore,sand control techniques must be factored into process optimization and cost reduction plans. 展开更多
关键词 Wireline log Stress Geo-mechanicanical characterization Sand prediction niger delta
在线阅读 下载PDF
上一页 1 2 141 下一页 到第
使用帮助 返回顶部