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Effect of Oil Spillage on the Growth of Cassava in Niger Delta Region of Nigeria

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Effect of Oil Spillage on the Growth of Cassava in Niger Del...

作者： Akpang paul john 沈阳农业大学

学位级别：硕士

Cassava has grown and developed from being a minor crop to becoming a major crop consumed by several homes in the ***,the incessant oil spillage and crude oil pollution has increased the concern on the productivity of this crop in the Niger Delta *** the research was aimed at providing empirical evidence on the actual impact of crude oil spillage in the Niger delta on the soil and productivity of cassava *** specific objectives of the study were to assess the socio-economic characteristics of cassava producers in the Niger Delta,evaluate the effects of the crude oil spill on the soil properties and cassava yield in area,compare the difference in yield with communities not affected by oil spill,analyses the efforts of oil companies in the communities and make policy *** study adopted a mixed research approach that employed questionnaire to gain insight from farmers on the effect of oil spillage on their productivity and a lab test of soil sample for examining the effect of oil spill on soil *** m ai n results ar e as fo l l o ws :（1）The study found a net margin of N27,218.17 and N18,382.17 per cassava producer in non-oil and oil spill areas in the Niger Delta Region,*** spills have resulted in a 31% fall in cassava producer *** to the test of difference,there is a significant difference of 8,836 in cassava producers’ net margin（***）between non-oil and oil spill locations.（2）For oil spill and non-oil spill communities,the yearly fixed cost and total variable cost per hectare cassava grower were N6,799.15 and N19,268.68,***,frying pans,diggers,and cutlasses were the most important fixed costs in cassava production,accounting for 34.03%,11.57%,10.82%,and 9.64% of total fixed costs,***,fertilizers,planting supplies,transportation,and processing were the greatest operational cost components,accounting for 22.49%,20.92%,15.76%,14.80%,and 16.24% of total vari

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Reactive Oxygen Species and Oxidative Stress in the Pathogenesis of MAFLD

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Journal of Clinical and Translational Hepatology 2022年第5期10卷 939-946页

作者： Kathleen Clare john F.Dillon paul N.Brennan Royal Alexandra Hospital PaisleyNHS Greater Glasgow and ClydePA29PNUK University of Dundee Ninewells Hospital and Medical SchoolDundeeDD19SYUK University of Edinburgh Edinburgh BioQuarter5 Little France DriveEH164UUUK

The pathogenesis of metabolic-associated fatty liver disease(MAFLD)is complex and thought to be dependent on multiple parallel hits on a background of genetic *** evidence suggests that MAFLD progression is a dynamic two-way process relating to repetitive bouts of metabolic stress and inflammation interspersed with endogenous anti-inflammatory reparative *** MAFLD,excessive hepatic lipid accumulation causes the production of lipotoxins that induce mitochondrial dysfunction,endoplasmic reticular stress,and over production of reactive oxygen species(ROS).Models of MAFLD show marked disruption of mitochondrial function and reduced oxidative capacitance with impact on cellular processes including mitophagy,oxidative phosphorylation,and mitochondrial *** excess,ROS modify insulin and innate immune signaling and alter the expression and activity of essential enzymes involved in lipid *** can also cause direct damage to intracellular structures causing hepatocyte injury and *** select cases,the use of anti-oxidants and ROS scavengers have been shown to diminish the proapoptopic effects of fatty *** this link,endogenous anti-oxidant pathways have been a target of interest,with Nrf2 activation showing a reduction in oxidative stress and inflammation in models of *** hormone receptorβ(THRβ)agonists and nuclear peroxisome proliferationactivated receptor(PPAR)family have also gained interest in reducing hepatic lipotoxicity and restoring hepatic function in models of ***,the true interplay between the clinical and molecular components of MAFLD progression remain only partly *** recently,multiomics-based strategies are being adopted for hypothesis-free analysis of the molecular changes in *** profiling maps the unique genotype-phenotype associations in MAFLD and with various single-cell tran scriptome-based projects underway,there is hope of novel physiological insigh

关键词： Fatty liver disease Metabolic-associated fatty liver disease Nonalcoholic steatohepatitis Reactive oxidation species Oxidative stress

The biological fate of the polymer nanocarrier material monomethoxy poly(ethylene glycol)-block-poly(D,L-lactic acid)in rat

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Acta Pharmaceutica Sinica B 2021年第4期11卷 1003-1009页

作者： Xiangjun Meng Zhi Zhang Jin Tong Hui Sun john paul Fawcett Jingkai Gu Research Center for Drug Metabolism School of Life SciencesJilin UniversityChangchun 130012China Beijing Institute of Drug Metabolism Beijing 102209China School of Pharmaceutical Sciences Tsinghua UniversityBeijing 100084China

Monomethoxy poly(ethylene glycol)-block-poly(D,L-lactic acid)(PEG-PLA)is a typical amphiphilic di-block copolymer widely used as a nanoparticle carrier(nanocarrier)in drug *** the in vivo fate of PEG-PLA is required to evaluate its overall safety and promote the development of PEG-PLA-based nanocarrier drug delivery ***,acquiring such understanding is limited by the lack of a suitable analytical method for the bioassay of *** this study,the pharmacokinetics,biodistribution,metabolism and excretion of PEG-PLA were investigated in rat after intravenous *** results show that unchanged PEG-PLA is mainly distributed to spleen,liver,and kidney before being eliminated in urine over 48 h mainly(>80%)in the form of its PEG *** study provides a clear and comprehensive picture of the in vivo fate of PEG-PLA which we anticipate will facilitate the scientifc design and safety evaluation of PEG-PLA-based nanocarrier drug delivery systems and thereby enhance their clinical development.

关键词： Monomethoxy poly(ethylene glycol)-block-poly(D,L-lactic acid) Polymer Nanocarrier material Pharmacokinetics Biodistribution Metabolism Excretion Rat

An improved culturing method for opiine fruit fly parasitoids and its application to parasitoid monitoring in the field

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Insect Science 2018年第1期25卷 99-108页

作者： Ayad Masry Michael J. Furlong Anthony R. Clarke john paul Cunningham School of Earth Environmental and Biological Sciences School Queensland University of Technology (QUT) Brisbane Queensland Australia School of Biological Sciences the University of Queensland St Lucia Queensland Australia plant Biosecurity Cooperative Research Centre Bruce ACT Australia Department of Economic Development Jobs Transport and Resources AgriBio Centre La Trobe University Bundoora Victoria Australia

Good culturing methods play an important role in the study of insect behavior and its application to pest management. Here, we describe and validate a new method for rearing the parasitoid wasp, Diachasmirnorpha kraussii, which attacks some of the world＇s worst fruit fly pests and is an internationally used biological control agent. Our method differs from standard culturing approaches by presenting adult wasps with host- infested artificial media within a ＂culturing bag,＂ which mimics a natural （fruit） oviposition substrate. In laboratory trials using wild collected D. kraussii, the culturing bag method was compared to the use of host-infested nectarines, and a commonly used laboratory method of presenting host-infested artificial media within Petri dishes. The culturing bag method proved to be a significant improvement on both methods, combining the advantages of high host survival in artificial media with parasitism levels that were the equivalent to those recorded using host-infested fruits. In our field study, culturing bags infested with the Queensland fruit fly, Bactrocera tryoni, and hung in a mixed peach and nectarine orchard proved to be effective ＂artificial fruits＂ attracting wild D. kraussii for oviposition. Significantly more adult wasps were reared from the culturing bags compared to field collected fruits. This was shown to be due to higher fruit fly larval density in the bags, as similar percentage parasitism rates were found between the culturing bags and ripe fruits. We discuss how this cheap, time-efficient method could be applied to collecting and monitoring wild D. kraussii populations in orchards, and assist in maintaining genetic variability in parasitoid laboratory cultures.

关键词： Bactrocera biological control fruit fly mass rearing natural enemies Tephritidae wasp

Apoptosis is not an invariable component of in vitro models of cortical cerebral ischaemia

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Cell Research 2004年第3期14卷 241-250页

作者： paul Alexander JONES,Gillian Ruth MAY,Joyce Ann MCLUCKIE,Akinori IWASHITA,john SHARKEY Fujisawa Institute of Neuroscience Division of Neuroscience University of Edinburgh 1 George Square Edinburgh UK Medical Information Eli Lilly and Company Ltd Lilly House Priestley Road Basingstoke RG24 9NL UK Fujisawa Institute of Neurosdence Division of Neuroscience University of Edinburgh 1 George Square Edinburgh UK Medicinal Biology Research Laboratories Fujisawa Pharmaceuticals Co.Ltd. 2-1-6 Kashima Yodogawa-ku Osaka 532-5814 Japan Fujisawa Institute of Neuroscience Division of Neuroscience University of Edinburgh 1 George Square Edinburgh UK

Characterising the mechanisms of cell death following focal cerebral ischaemia has been hampered by a lack of an in vitro assay emulating both the apoptotic and necrotic features observed in vivo. The present study systematically characterised oxygen-glucose-deprivation (OGD) in primary rat cortical neurones to establish a reproducible model with components of both cell-death endpoints. OGD induced a time-dependent reduction in cell viability, with 80% cell death occurring 24 h after 3 h exposure to 0% O2 and 0.5 mM glucose. Indicative of a necrotic component to OGD induced cell death, N-methyl-D-aspartate (NMDA) receptor inhibition with MK-801 attenuated neuronal loss by 60%. The lack of protection by the caspase inhibitors DEVD-CHO and z-VAD-fmk suggested that under these conditions neurones did not die by an apoptotic mechanism. Moderating the severity of the insult by decreasing OGD exposure to 60 min did not reduce the amount of necrosis, but did induce a small degree of apoptosis (a slight reductio

关键词： oxygen-glucose-deprivation caspase cortical necrosis.

Irritable bowel syndrome: A microbiome-gut-brain axis disorder?

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World Journal of Gastroenterology 2014年第39期20卷 14105-14125页

作者： paul J Kennedy john F Cryan Timothy G Dinan Gerard Clarke 1.15 Biosciences Institute Department of Psychiatry Alimentary Pharmabiotic Centre University College Cork Cork Ireland Department of Anatomy and Neuroscience Alimentary Pharmabiotic CentreUniversity College CorkCork Ireland

Irritable bowel syndrome(IBS) is an extremely prevalent but poorly understood gastrointestinal disorder. Consequently, there are no clear diagnostic markers to help diagnose the disorder and treatment options are limited to management of the symptoms. The concept of a dysregulated gut-brain axis has been adopted as a suitable model for the disorder. The gut microbiome may play an important role in the onset and exacerbation of symptoms in the disorder and has been extensively studied in this context. Although a causal role cannot yet be inferred from the clinical studies which have attempted to characterise the gut microbiota in IBS, they do confirm alterations in both community stability and diversity. Moreover, it has been reliably demonstrated that manipulation of the microbiota can influence the key symptoms, including abdominal pain and bowel habit, and other prominent features of IBS. A variety of strategies have been taken to study these interactions, including probiotics, antibiotics, faecal transplantations and the use of germ-free animals. There are clear mechanisms through which the microbiota can produce these effects, both humoral and neural. Taken together, these findings firmly establish the microbiota as a critical node in the gut-brain axis and one which is amenable to therapeutic interventions.

关键词： Irritable bowel syndrome Microbiome Anxiety Tryptophan Abdominal pain Gastrointestinal motility Cognition

Soil quality estimation using environmental covariates and predictive models:an example from tropical soils of Nigeria

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Ecological Processes 2022年第1期11卷 946-967页

作者： Isong Abraham Isong Kingsley john paul Bassey Okon Peter Ikor Ogban Sunday Marcus Afu Department of Soil Science Faculty of AgricultureUniversity of CalabarCalabar PMB 1115Nigeria Department of Soil Science and Soil Protection Faculty of AgrobiologyFoodand Natural ResourcesCzech University of Life SciencesKamýcká12916500 PragueCzech Republic

Background:Information addressing soil quality in developing countries often depends on results from small experimental plots,which are later extrapolated to vast areas of agricultural *** approach often results in misin-formation to end-users of land for sustainable soil nutrient *** objective of this study was to estimate the spatial variability of soil quality index(SQI)at regional scale with predictive models using soil–environmental ***:A total of 110 composite soil samples(0–30 cm depth)were collected by stratified random sampling schemes at 2–5 km intervals across the Cross River State,Nigeria,and selected soil physical and chemical properties were *** employed environmental covariates derived from a digital elevation model(DEM)and Senti-nel-2 imageries for our modelling *** measured soil quality using two approaches[total data set(TDS)and minimum data set(MDS)].Two scoring functions were also applied,linear(L)and non-linear(NL),yielding four indices(MDS_L,MDS_NL,TDS_L,and TDS_NL).Eleven soil quality indicators were used as TDS and were further screened for MDS using principal component analysis(PCA).Random forest(RF),support vector regression(SVR),regression kriging(RK),Cubist regression,and geographically weighted regression(GWR)were applied to predict SQI in unsampled ***:The computed SQI via MDS_L was classified into five classes:≤0.38,0.38–0.48,0.48–0.58,0.58–0.68,and≥0.68,representing very low(classⅤ),low(classⅣ),moderate(classⅢ),high(classⅡ)and very high(classⅠ)soil quality,*** model was robust in predicting soil quality(R^(2)=0.21,CCC=0.39,RMSE=0.15),while RF was a model with inferior performance(R^(2)=0.02,CCC=0.32,RMSE=0.15).Soil quality was high in the southern region and low in the northern *** soil quality class(>49%)and moderate soil quality class(>14%)dominate the study area in all predicted models ***:Structural stability index,sand content,soil oga

关键词： Decision support system Geospatial technology Predictive model Remote sensing Soil quality

Impact of a national basic skills in colonoscopy course on trainee performance: An interrupted time series analysis

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World Journal of Gastroenterology 2020年第23期26卷 3283-3292页

作者： Keith Siau James Hodson john T Anderson Roland Valori Geoff Smith paul Hagan Marietta Iacucci paul Dunckley Joint Advisory Group on Gastrointestinal Endoscopy Royal College of PhysiciansLondon NW14LEUnited Kingdom NIHR Biomedical Research Centre University of BirminghamBirmingham B152TTUnited Kingdom Institute of Translational Medicine University Hospitals BirminghamBirmingham B152TTUnited Kingdom Department of Gastroenterology Gloucestershire Hospitals NHSFTCheltenham GL537ANUnited Kingdom Department of Gastroenterology Imperial College NHS Foundation TrustLondon NW14LEUnited Kingdom Endoscopy Department Derby Royal HospitalDerby GL13NNUnited Kingdom

BACKGROUND The Joint Advisory Group on Gastrointestinal Endoscopy basic skills in colonoscopy(BSC) course was introduced in 2009 to improve colonoscopy training within the United Kingdom, but its impact on trainee performance is *** To assess whether attendance of the BSC could improve colonoscopy *** Trainees awarded colonoscopy certification between 2011-2016 were stratified into 3 groups according to pre-course procedure count( 140).Study outcomes, comprising the unassisted caecal intubation rate(CIR) and the performance indicator of colonic intubation(PICI), were studied over the 50 procedures pre and post-course. Interrupted time series analyses were performed to detect step-change changes attributable to the *** A total of 369 trainees with pre-course procedure counts of 140(n = 130) were included. Over the 50 pre-course procedures,significant linear improvements in CIR were found, with average increases of 4.2,3.6 and 1.7 percentage points(pp) per 10 procedures performed in the 140 groups respectively(all P 140(86% to 87%;P = 0.354) groups. For PICI, significant step-change improvements were seen in all three groups, with average increases of 5.6 pp(P < 0.001), 5.4 pp(P = 0.003) and 3.9 pp(P = 0.014) *** Attendance of the BSC was associated with a significant step-change improvement in PICI, regardless of prior procedural experience. However, CIR data suggest that the optimal timing of course attendance appears to be at earlier stages of training(< 70 procedures).

关键词： Colonoscopy Training Course Competency development Skills Endoscopy

Seasonal exports of phosphorus from intensively fertilised nested grassland catchments

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Journal of Environmental Sciences 2013年第9期25卷 1847-1857页

作者： Ciaran Lewis Rashad Rafique Nelius Foley paul Leahy Gerard Morgan john Albertson Sandeep Kumar Gerard Kiely Department of Civil and Environmental Engineering University College Cork Department of Microbiology and Plant Biology University of Oklahoma Environmental Research Institute University College Cork Aquatic Services Unit Environmental Research Institute University College Cork Department of Civil and Environmental Engineering Duke University Department of Plant Science South Dakota State University

We carried out a one year （2002） study of phosphorus （P） loss from soil to water in three nested grassland catchments with known P input in chemical fertilizer and animal liquid slurry applications. Chemical fertilizer was applied to the grasslands between March and September and animal slurry was applied over the twelve months. The annual chemical P fertilizer applications for the 17 and 211 ha catchments were 16.4 and 23.7 kg P/ha respectively and the annual slurry applications were 10.7 and 14.0 kg P/ha, respectively. The annual total phosphorus （TP） export in stream-flow was 2.61, 2.48 and 1.61 kg P/ha for the 17, 211 and 1524 ha catchments, respectively, compared with a maximum permissible （by regulation） annual export of ca. 0.35 kg P/ha. The export rate （ratio of P export to P in land applications） was 9.6% and 6.6% from the 17 and 211 ha catchments, respectively. On average, 70% of stream flow and 85% of the P export occurred during the five wet months （October to February） indicating that when precipitation is much greater than evaporation, the hydrological conditions are most favourable for P export. However the soil quality and land use history may vary the results. Particulate P made up 22%, 43% and 37% of the TP export at the 17, 211 and 1524 ha catchment areas, respectively. As the chemical fertilizer was spread during the grass growth months （March to September）, it has less immediate impact on stream water quality than the slurry applications. We also show that as the catchment scale increases, the P concentrations and P export decrease, confirming dilution due to increasing rural catchment size. In the longer term, the excess P from fertilizer maintains high soil P levels, an antecedent condition favourable to P loss from soil to water. This study confirms the significant negative water quality impact of excess P applications, particularly liquid animal slurry applications in wet winter months. The findings suggest that restricted P application in w

关键词： phosphorus fertilizer slurry exports grassland land management water quality eutrophication