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Open Journal of Ecology 2018年第11期8卷 607-621页

作者： katherine temitope ogundele Emmanuel Ayodele Oluyemi John Adekunle Oyedele Oyekunle Oladotun Wasiu Makinde Sejlo Temidayo Gbenu Centre for Energy Research and Development Obafemi Awolowo University Ile-Ife Nigeria Department of Chemistry Obafemi Awolowo University Ile-Ife Nigeria

This study measured the radioactivity level in the sediments of Eko-Ende Dam in Ifelodun Local Government Area, Osun State, Nigeria and assessed the radiological impact associated. Thirty six (36) sediment samples were collected from three different points within the Dam for a period of 12 months. The samples were analyzed using Gamma Ray Spectrometer. The radiological hazards due to natural radionuclides content, such as absorbed dose rate (DR), annual effective dose rate (AEDE), effective life cancer risk (ELCR), activity utilization index (AUI), internal radiation hazard (Hin) and external radiation hazard (Hex) in the sediment samples were calculated. The calculated radiological parameters were compared with recommended safety limits and internationally approved values. The radium equivalent activity, internal hazard index, annual effective dose equivalent and effective life cancer risk values of the sediment samples were lower than the permissible limit. Thus, the study area might not pose immediate health implications to the general public, but prolonged exposure could lead to radiation related health hazards.

关键词： Natural Radioactivity Radiological Parameters Dam Eko-Ende Nigeria

Additive neurorestorative effects of exercise and docosahexaenoic acid intake in a mouse model of Parkinson’s disease

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Neural Regeneration Research 2025年第2期20卷 574-586页

作者： Olivier Kerdiles Méryl-Farelle Oye Mintsa Mi-mba katherine Coulombe Cyntia Tremblay VincentÉmond Martine Saint-Pierre Clémence Rouxel Line Berthiaume Pierre Julien Francesca Cicchetti Frédéric Calon Facultéde pharmacie UniversitéLaval1050 Avenue de la MédecineQuebecQCCanada Axe Neuroscience Centre de recherche du CHU de Québec-UniversitéLaval(Pavillon CHUL)2705 Boulevard LaurierQuebecQCCanada Institute of Nutrition and Functional Foods QuebecQCCanada Optinutribrain International Associated Laboratory(NutriNeuro FranceINAFCanada)QuebecQCCanada Axe Endocrinologie et Néphrologie Centre de recherche du CHU de Québec-UniversitéLavalQuebecQCCanada Département de Médecine Facultéde MédecineUniversitéLavalQuebecQCCanada Département de Psychiatrie et Neurosciences Facultéde MédecineQuebecQCCanada

There is a need to develop interventions to slow or reverse the degeneration of dopamine neurons in Parkinson’s disease after *** that preclinical and clinical studies suggest benefits of dietary n-3 polyunsaturated fatty acids,such as docosahexaenoic acid,and exercise in Parkinson’s disease,we investigated whether both could synergistically interact to induce recovery of the dopaminergic ***,mice received a unilateral stereotactic injection of 6-hydroxydopamine into the striatum to establish an animal model of nigrostriatal *** weeks after lesion,animals were fed a docosahexaenoic acid-enriched or a control diet for the next 8 *** this period,the animals had access to a running wheel,which they could use or *** acid treatment,voluntary exercise,or the combination of both had no effect on(i)distance traveled in the open field test,(ii)the percentage of contraversive rotations in the apomorphine-induction test or(iii)the number of tyrosine-hydroxylase-positive cells in the substantia nigra pars ***,the docosahexaenoic acid diet increased the number of tyrosine-hydroxylase-positive terminals and induced a rise in dopamine concentrations in the lesioned *** to docosahexaenoic acid treatment or exercise alone,the combination of docosahexaenoic acid and exercise(i)improved forelimb balance in the stepping test,(ii)decreased the striatal DOPAC/dopamine ratio and(iii)led to increased dopamine transporter levels in the lesioned *** present results suggest that the combination of exercise and docosahexaenoic acid may act synergistically in the striatum of mice with a unilateral lesion of the dopaminergic system and provide support for clinical trials combining nutrition and physical exercise in the treatment of Parkinson’s disease.

关键词： 6-hydroxydopamine dopamine dopamine transporter exercise neurorestoration Parkinson’s disease polyunsaturated fatty acids omega-3

A Particle Induced X-Ray Emission (PIXE) Analysis of Heavy Metals in Soil and Plantain (<i>Musa paradisiaca</i>) Leaves at an Artisanal Gold Mining Settlement in Southwestern Nigeria

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Open Journal of Ecology 2019年第6期9卷 200-208页

作者： Makinde Oladotun Wasiu Oluyemi Emmanuel Ayodele Olabanji Iyabo Oluremi Adesiyan Adewale Taoreed Eludoyin Adebayo Oluwole ogundele katherine temitope Gbenu Sejlo Temidayo Tubosun Isaac Ayodele C.E.R.D Obafemi Awolowo University Ile-Ife Nigeria Departments of Chemistry Obafemi Awolowo University Ile-Ife Nigeria Department of Geology Obafemi Awolowo University Ile-Ife Nigeria Departments of Geography Obafemi Awolowo University Ile-Ife Nigeria

The study examined the contamination levels of the soil and plantain leaves in three communities in Atakunmosa west local government area of Osun State in southwest Nigeria, where gold mining activities have recently become intensive. Plantain is a major food crop, whose leaves are used to wrap food items for household consumption. The objectives were to examine the heavy metal concentrations in the soil and plantain leaves around the gold mine site and compare them with standard recommended safe limits for the environment. Soil and plantain leaves were sampled at different locations around the sites and at a control site from a neighboring local government area with no history of gold mining activities between March 2015 and February 2016. Both soil and leave samples were processed and analyzed for selected heavy metals (Cd, As, Cu, Zn, Cr, Mn and Fe) using the Particle Induced X-ray Emission (PIXE) in the laboratory. The study showed higher concentrations than the World Health Organization’s recommended safe limits of the heavy metals in the soils and plantain leaves. Dry season concentrations of the variables were also higher than the wet season and the heavy metal concentrations at the control station were significantly (p < 0.05) lower than those of the mining environment. The study concluded that the ecosystems in the artisanal gold mining region are vulnerable to bioaccumulation of heavy metals and the leaves from the sites are sources of heavy metal contamination if consumed or used to wrap food items.

关键词： Artisanal Mining Soil and Food Contamination Particle Induced X-Ray Emis-sion Bioaccumulation

Two-dimensional d-πconjugated metal-organic framework based on hexahydroxytrinaphthylene

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Nano Research 2021年第2期14卷 369-375页

作者： Zheng Meng katherine A.Mirica Department of Chemistry Burke Laboratory41 College Streety Dartmouth CollegeHanoverNH 03755USA

The development of new two-dimensional(2D)d-πconjugated metal-organic frameworks(MOFs)holds great promise for the construction of a new generation of porous and semiconductive *** paper describes the synthesis,structural characterization,and electronic properties of a new d-πconjugated 2D MOF based on the use of a new ligand 2,3,8,9,14,*** reticular self-assembly of this largeπ-conjugated organic building block with Cu(II)ions in a mixed solvent system of 1,3-dimethyl-2-imidazolidinone(DMI)and H2 O with the addition of ammonia water or ethylenediamine leads to a highly crystalline MOF Cu3(HHTN)2,which possesses pore aperture of 2.5 ***3(HHTN)2 MOF shows moderate electrical conductivity of 9.01×10^(-8)S·cm^(-1)at 385 K and temperature-dependent band gap ranging from 0.75 to 1.65 *** chemical oxidation by l2,the conductivity of Cu3(HHTN)2 can be increased by 360 *** access to HHTN based MOF adds an important member to previously reported MOF systems with hexagonal lattice,paving the way towards systematic studies of structure-property relationships of semiconductive MOFs.

关键词： two-dimensional metal-organic framework(MOF) trinaphthylene conductive MOF

Applications of carbon nanomaterials in perovskite solar cells for solar energy conversion

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Nano Materials Science 2021年第3期3卷 276-290页

作者： katherine Moore Wei Wei Department of Mechanical Engineering Wichita State University1845 Fairmount StWichitaKS67260USA

The energy issues and environmental concern have led to intense research activities in renewable energy conversion,such as photovoltaic(PV)to convert solar energy into *** solar cells(PSCs)based on metal halides are rapidly emerging as the most promising and competing PV technology due to its high record power conversion efficiencies and potentially low production *** carbon materials,which are abundantly available and low-cost,are introduced into the *** article provides a mini review of applications of carbon materials for perovskite solar ***,a brief introduction of the development of perovskite solar cell is ***,applications of carbon nanomaterials in perovskite solar cells are presented and ***,an outlook and perspective on the future research directions of carbon nanomaterial for perovskite solar cells is provided.

关键词： Carbon nanomaterials Perovskite solar cells Solar energy

Plasmon point spread functions： How do we model plasmon-mediated emission processes？

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Frontiers of physics 2014年第1期9卷 3-16页

作者： katherine A. Willets Department of Chemistry University of Texas at AustinWelch Hall 1.202 105 E 2~TH ST. STOP A5300 Austin TX 78712 USA

A major challenge with studying plasmon-mediated emission events is the small size of plasmonic nanoparticles relative to the wavelength of light. Objects smaller than roughly half the wavelength of light will appear as diffraction-limited spots in far-field optical images, presenting a significant experimental challenge for studying plasmonic processes on the nanoscale. Super-resolution imaging has recently been applied to plasmonic nanosystems and allows plasmon-mediated emission to be resolved on the order of ~5 nm. In super-resolution imaging, a diffraction-limited spot is fit to some model function in order to calculate the position of the emission centroid, which represents the loca- tion of the emitter. However, the accuracy of the centroid position strongly depends on how well the fitting function describes the data. This Perspective discusses the commonly used two-dimensional Gaussian fitting function applied to super-resolution imaging of plasmon-mediated emission, then introduces an alternative model based on dipole point spread flmctions. The two fitting models are compared and contrasted for super-resolution imaging of nanoparticle scattering/luminescence, surface-enhanced Raman scattering, and surface-enhanced fluorescence.

关键词： plasmon point spread function dipole super-resolution surface-enhanced Ramanscattering (SERS)

The state of mountain research in Canada

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Journal of Mountain Science 2022年第10期19卷 3013-3025页

作者： Graham MCDOWELL katherine HANLY Department of Geography University of CalgaryCalgaryABT2NiN4Canada Department of Geography University of ZurichCH-8006 ZurichSwitzerland

Nearly a quarter of Canada’s landmass is covered by mountainous terrain,making mountains an important aspect of the physical and human geography of the *** areas in Canada have motivated a great deal of research activity,yet the state of mountain research in the country has never been systematically characterized,precluding a detailed understanding of what is being studied,when,where,how,and by *** response,we conducted a systematic scoping review to rigorously identify,collate,and critically examine existing peer-reviewed articles related to mountains in Canada.2,888 articles were included in our review,which reveals strong biases towards work in the natural sciences and in the mountain west,with little work to date in the social and health sciences or in other mountainous regions of the *** results demonstrate that Canada is among the most productive contributors to mountain research globally,but that topical and geographical biases in existing research effort leave important gaps that must be addressed to successfully navigate challenges and opportunities facing mountain areas in *** provide a roadmap to guide future mountain-focused research activities in the country.

关键词： Canada Mountains Systematic scoping review Research

COP28 Makes It Official: Fossil Fuels Cause Climate Change

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Engineering 2024年第6期37卷 3-5页

作者： katherine Bourzac Senior Technology Writer

On November 30,2023,amidst outrage over its leadership’s ties to the oil and gas industry[1],COP28—shorthand for the 28th United Nations(UN)“Conference of the Parties”Climate Change meeting—began in Dubai,United Arab Emirates(UAE).However,by the end of the conference on December 12,its attendees had surprisingly reached agreement on a handful of steps to address the challenges posed by climate *** biggest surprise?Explicitly identifying fossil fuels as the root cause of climate *** the first time in the summit’s 28-year history,delegates representing nearly 200 countries acknowledged the role of fossil fuels in driving climate *** agreed to work on “transitioning away from fossil fuels in energy systems,in a just,orderly,and equitable manner,accelerating action in this critical decade,so as to achieve net zero by 2050 in keeping with the science”[2].

关键词： representing driving steps

The contribution of botanic gardens to ex situ conservation through seed banking

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Plant Diversity 2017年第6期39卷 373-378页

作者： katherine O'Donnell Suzanne Sharrock Botanic Gardens Conservation International Descanso House

Target 8 of the Global Strategy for Plant Conservation calls for 'at least 75 per cent of threatened plant species in ex situ collections, preferably in the country of origin, and at least 20 per cent available for recovery and restoration programmes by 2020'.Botanic gardens make a significant contribution to ex situ conservation of wild species with more than a third of plant species represented in botanic gardens collections. These collections are a combination of living collection and seed banked material. Seed banking can provide an efficient form of conservation for wild plant genetic *** from Botanic Gardens Conservation International's(BGCI) databases(GardenSearch,PlantSearch, ThreatSearch and GlobalTreeSearch) has been analysed as well as survey data to report on global, regional and national seed banking *** from BGCI's databases indicates that there are at least 350 seed banking botanic gardens in 74 countries. In total 56,987 taxa have been banked including more than 9000 taxa that are threatened with extinction. 6881 tree species are stored in ex situ seed bank collections. More than half(3562) of these tree species are single country endemics and represent species from more than 166 *** study suggests that institutions are increasingly conserving plant species via seed *** the majority of species in collections that have a conservation assessment are not threatened with extinction. This disjunction between species that are threatened and those conserved in seed banks needs to be addressed. Data from BGCI's databases can be used to enable prioritisation of threatened plant species for collection and conservation in seed banks. Further recommendations for botanic gardens involved in seed conservation are presented.

关键词： Seed banking GSPC ex situ conservation Conservation assessments Botanic gardens

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Recurrent varicocele

Asian Journal of Andrology 2016年第2期18卷 229-233,J0004,J0005页

作者： katherine Rotker Mark Sigman Department of Surgery division of Urology Brown University 2 Dudley Street Suite #174 Providence RI 02905 USA.

Varicocele recurrence is one of the most common complications associated with varicocele repair. A systematic review was performed to evaluate varicocele recurrence rates, anatomic causes of recurrence, and methods of management of recurrent varicoceles. The PubMed database was evaluated using keywords ＂recurrent＂ and ＂varicocele＂ as well as MESH criteria ＂recurrent＂ and ＂varicocele.＂ Articles were not included that were not in English, represented single case reports, focused solely on subclinical varicocele, or focused solely on a pediatric population （age 〈18）. Rates of recurrence vary with the technique of varicocele repair from 0% to 35%. Anatomy of recurrence can be defined by venography. Management of varicocele recurrence can be surgical or via embolization.

关键词： infertility recurrence varicocele