bluuebunny/crossref_metadata_2025_split huggingface dataset:
A novel capillary microextraction on ordered mesoporous titania coating combined with electrothermal vaporization inductively coupled plasma mass spectrometry for the determination of V, Cr and Cu in environmental and biological samples
Authors: Wu Yiwei , Hu Bin , Hu Wenling , Jiang Zucheng , Li Boyangzi 
Published: January 2007

AbstractIn this work, an ordered mesoporous titania film was introduced to coat a capillary by means of sol–gel technique. Sol–gel titania coating was developed for the preconcentration/separation of trace V, Cr and Cu by capillary microextraction (CME), and the adsorbed analytes were eluted for electrothermal vaporization inductively coupled plasma mass spectrometry (ETV‐ICP‐MS) detection. By immobilizing sol–gel titania on the inner surface of a fused‐silica microextraction capillary, the sol–gel titania coating was prepared easily. Its adsorption properties, stability and the factors affecting the adsorption behaviors of V, Cr and Cu were investigated in detail. At pH range of 7 to 9, the titania‐coated capillary (50 cm × 0.25 mm) is selective towards V, Cr and Cu, and the target analytes could be desorbed quantitatively with 50 µl of 1.0 mol l−1 HNO3 at the rate of 0.05 ml min−1. With a consumption of 2 ml sample solution, an enrichment factor of 33.3, and a detection limit (3 s) of 1.1 pg ml−1 (10.5 fg) for V; 3.3 pg ml−1 (33.0 fg) for Cr and 6.3 pg ml−1 (63.1 fg) for Cu respectively were obtained. The precisions Relative Standard Deviations (RSDs) for nine replicate measurements of 1 ng ml−1 V, Cr and Cu were 3.4, 5.1 and 6.4%, respectively. The proposed method has been applied to the determination of V, Cr and Cu in human urine and lake water, and the recoveries for these elements were 89.2∼105%. The developed method was also applied to the determination of the target elements in NIES No. 10‐a (rice flour‐unpolished) and NIES No. 9 (sargasso) certified reference materials, and the results found are in good agreement with the certified values. Copyright © 2007 John Wiley & Sons, Ltd.
Astrocytic hypertrophy in dysmyelination influences the diffusion anisotropy of white matter
Authors: Harsan Laura A. , Poulet Patrick , Guignard Blandine , Parizel Nathalie , Skoff Robert P. , Ghandour M. Said 
Published: February 2007

AbstractThe effect of a proteolipid protein (PLP) mutation on the developing white matter anisotropy was examined by diffusion tensor magnetic resonance imaging (DT‐MRI) in a noninvasive study of a mouse model of Pelizaeus‐Merzbacher disease (PMD). The jimpy PLP mutation in mice produces an irreversible dysmyelination in jimpy males, whereas heterozygous females exhibit a transient hypomyelination, as assessed by a longitudinal study of the same mice during development. Modifications of the different individual DT‐MRI parameters were highlighted by specific changes in tissue structures caused by the mutation that includes the hypomyelination, axonal abnormalities, and recovery. Astrocytic hypertrophy is a striking cellular event in dysmyelinated jimpy brain, where most axons or bundles of fibers are entirely wrapped by astrocyte cytoplasmic processes, so its influences on DT‐MRI parameters in dysmyelination were examined for the first time. DT‐MRI data of the jimpy brain were compared with those obtained from dysmyelination of (oligo‐TTK) transgenic mice, induced by oligodendrocyte killing, which have a mild astrocyte hypertrophy (Jalabi et al., 2005), and from recovering jimpy females, which have reduced astrocyte hypertrophy. The unique morphological feature of astrocytes in jimpy males coupled with an increase in the water channel protein aquaporin 4 (AQP4) was found to facilitate the directional water diffusion in the white matter. In addition to the major changes of DT‐MRI parameters in the two dysmyelinated mice caused by the myelin loss and axonal modifications, the amplified magnitude of radial and axial diffusions in jimpy males was attributed principally to the strongly pronounced astrocyte hypertrophy. © 2007 Wiley‐Liss, Inc.
Effects of hyperbaric oxygen treatment on tendon graft and tendon‐bone integration in bone tunnel: Biochemical and histological analysis in rabbits
Authors: Yeh Wen‐Ling , Lin Song‐Shu , Yuan Li‐Jen , Lee Kam‐Fai , Lee M.Y. , Ueng Steve W.N. 
Published: February 2007

AbstractDespite moderate success in clinical applications, outcome of tendon grafts employed for anterior cruciate ligament (ACL) reconstruction remains unsatisfactory. This study investigated the effects of hyperbaric oxygen (HBO) on neovascularization at the tendon‐bone junction, collagen fibers of the tendon graft, and the tendon graft‐bony interface incorporated into the osseous tunnel in rabbits. Forty rabbits were assigned to two groups. The HBO group was exposed to 100% oxygen at 2.5 atmospheres pressure for 2 h daily, 5 consecutive days in a week. The control group was maintained in cages exposed to normal air. Histological studies of 12 rabbits were performed postoperatively at 6, 12, and 18 weeks. Biomechanical studies of 24 rabbits were conducted postoperatively at 12 and 18 weeks. Electron microscopy (EM) analyses of four rabbits were performed postoperatively at 18 weeks. Experimental results demonstrated that a higher number of Sharpey's fibers bridged the newly formed fibrocartilage and graft in the HBO group than in the control group. In addition, HBO treatment increased neovascularization and enhanced the incorporation of the progressive interface between tendon graft and bone. Biomechanical analysis showed that the HBO group achieved higher maximal pullout strength than the control group. Examination by EM showed that HBO treatment resulted in regenerated collagen fibers with increased compaction and regularity. Based on experimental results, HBO treatment is a treatment modality that potentially improves outcome following ACL reconstruction. © 2007 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 25:636–645, 2007
Land degradation, soil conservation and the sediment load of the Yellow River, China: Review and assessment
Authors: Douglas Ian 
Published: February 2007

AbstractNinety per cent of the sediment load of the Yellow River, the world's muddiest river, comes from the loess plateau region in the middle course of the river. Control of this sediment supply is essential to avoid the danger of flooding in the lower reaches on the South China Plain. Since 1971, sediment loads entering the lower reaches have decreased, by 20 per cent as a result of lower precipitation, and by 27 per cent through soil conservation works and reservoir construction. Reductions in erosion can be obtained by restraining the formation of overland flow through promotion of an effective vegetation cover and elimination of the soil surface cover to encourage infiltration. Reservoir operation is a key to control of sediment movement through tributaries and along the main river. Water demands often conflict with sediment control, and, as a consequence, reservoir operation systems have changed several times in the past decade. The possibility of a further reduction in the sediment load of the Yellow River exists, but much depends on how rapidly control of grazing and deforestation leads to the establishment of plant cover on the loess plateau.
Application of a low‐cost database to soil erosion and soil conservation studies in the Awash Basin, Ethiopia
Authors: Griffiths J. S. , Richards K. S. 
Published: February 2007

AbstractIn large‐scale land resource planning exercises, Geographical Information Systems (GIS) form a valuable means of storing, retrieving, displaying, and analysing spatially‐referenced data, as well as enabling the simulation of the consequences of various alternative development options. However, at this scale only generalized policies for the allocation of finance can be made, and the implementation of those policies will invariably require detailed evaluation at the local level. This suggests that expenditure on the central planning process itself should be limited, with funds reserved for later site studies. The form of GIS adopted centrally should also lend itself to easy use and interpretation by policymakers and planners. These requirements suggest that GIS development using proprietary off‐the‐shelf database management software may be preferable to high‐technology GIS software. This paper outlines the development of such a GIS, based on dBase‐III‐plus and its internal programming language, in the analysis of problems of soil erosion and soil conservation in the large (110,000 km2) drainage basin of the Awash River in Ethiopia. The methodology employed involves the FAO modification of the Universal Soil Loss Equation, which clearly lacks a secure process basis, but is appropriate for the scale of planning involved and the quality of calibration data available. The GIS is used to map patterns of soil erosion, to identify target areas for conservation on the basis of criteria of sensitivity to land use change, and to assess the costs and benefits of conservation work in those areas. It is suggested that the simple form of GIS involved in this study has much to offer environmental managers in developing countries in the rapid development of plans for soil conservation.
Rehabilitation of alkaline wasteland on the gangetic alluvial plains of Uttar Pradesh, India, through afforestation
Authors: Singh Bajrang 
Published: February 2007

AbstractA few species of fuelwood trees were established on highly alkaline wasteland at Aligarh (27°5′ N., 78°4′ E.) in a tropical environment. Of these Prosopis juliflora produced maximum biomass (12.05 t ha−1) and had an energy content of 242.11 GJ ha−1 after 3.5 years growth period. The survival percentage of Terminalia arjuna was highest of those the species tried, but their growth and biomass production were inferior to that of Prosopis juliflora and Acacia nilotica. Some of the fuelwood tree plantations were raised without adding any soil amendment but suffered heavy mortality and could not produce any significant quantity of biomass. In another experiment Leucaena leucocephala was identified as a most promising species for afforestation on substandard soils; also it was found that a relatively high population density (of about 7,500 plants per hectare) is required to rehabilitate such land. Of the soil amendments tried, gypsum with farmyard manure and sand in equal proportion gave the better response (gypsum alone was also tried). Two species of shrubs: Sesbania sesban and Tamarix dioca have shown good adaptability in difficult habitats. After five years of afforestation the soil properties of the sites improved significantly, showing marked reduction in pH, EC and ESP values and an increase in organic carbon content.
Soil alkalinization and salinization in the djajerud Basin, Iran
Authors: Valles V. , Gholami M. , Lambert R. 
Published: February 2007

AbstractThe Djajerud Basin is located on the southern slopes of the Elburz Mountains, to the east of Tehran. Near its source, as the River is fed mainly by the melting of the winter snow and flows over tuffs and schists, its carbonate‐enriched water can induce soil alkalinization. The Djajerud River runs from its source across a gypsum and marl piedmont. Gypsum is dissolved and modifies the chemical quality of the waters, which lose their alkaline character and get more salty. These sulphate‐rich flows are less damaging because soil degradation hazards in the region are related more to salinization than to alkalinization.The Djajerud River waters next seep deep into a permeable deposition fan and feed water‐tables which merge into the groundwaters of the Varamin Plain (which are also fed by chloride‐rich waters from other sources). The chemical character of the Djajerud‐River changes in this section, developing a marked sodium chloride salinity. The soils in this part of the Basin, due to the high groundwater salinity, have poor drainage which prevents any agriculture. The River eventually flows into the highly saline endorrheic Daryachehnamak Lake.The concept of residual alkalinity is used to examine the chemical composition of the Djajerud River along its course and affords the determination of the soil degradation hazard in the various parts of the Basin.
A risk analysis methodology for assessing natural resources degradation
Authors: Cincotta R. , Péarez‐Trejo F. 
Published: February 2007

AbstractRisk analysis has been employed, amongst other things, both to estimate the probability of future water demand emergencies in reservoir systems (using simulation modelling), and to estimate environmental and public health risks (using empirical data). We assert that this framework, when coupled with simulation modelling, can be applied to examine and compare the impacts of resource exploitation, land use and production strategies which may cause land degradation. Our representation of risk analysis relies on the assumption that each land use strategy is associated with a risk of the system (i.e., social system, production system, ecosystem) attaining a subjectively unacceptable environmental condition (e.g. poor human nutrition, crop failure, degradation of a natural resource) sometime during a management planning period. The research methodology entails: (1) the identification of critical variables in the social and biological environment that are affected by exploitation and management of resources; (2) the identification through interviews, surveys, and research of regions of unacceptability in these variables that determine the dynamics of local environmental degradation; (3) the translation of resource policy and practice into a computer model of impact on the resource system; (4) many iterations of simulation of the system to determine the ‘risk of failing’ in each of the critical variables. The presentation of risk probabilities to decision‐makers represents a reduction of many simulations into an understandable estimate of environmental impact. More importantly, risk analysis is potentially a learning tool for human system studies, and an interface for applied social science and ecological research.
Effects of wildfire on a semidesert riparian woodland along the Turkwel river, Kenya, and management implications for turkana pastoralists
Authors: Oba Gufu 
Published: February 2007

AbstractRegeneration following a wildfire in a semidesert riparian woodland near the Turkwel River, Kenya was monitored from 2nd June, 1987 to 6th July, 1988. The pre‐fire tree density was 417 plants ha−1 and the canopy cover was 36.5 per cent ha−1. Hyphaene compressa (a palm) accounted for 93 per cent of total density and Acacia tortilis 6.9 per cent. A tortilis contributed a pre‐fire aboveground fuel biomass of 64.92 t ha−1, while H. compressa provided 23.35 t ha−1. The wildfire reduced tree canopy cover to about 7.0 per cent and resulted in a 100.0 per cent top‐kill of A. tortilis and 24.0 per cent for H. compressa. Seed germination of A. tortilis and canopy density of H. compressa saplings were stimulated by the wildfire. The post‐fire A. tortilis seedling density was 9 554 ha−1 compared to the pre‐fire density of 213 plants ha−1. Canopy cover of palms in the burnt area increased by 457.0 per cent, while crown heights increased by 100.0 per cent between the sampling dates. Where H. compressa palms were not top‐killed, recovery following the post‐burn period resulted in higher foliage yield compared to unburnt palms. In reproductive palms, burning delayed fruit production although the effect may not be long lasting.The impact of wildfire on this Turkwel riparian woodland has important management implications. Elimination of pod‐bearing A. tortilis by fire creates acute shortage of a critical dry season forage for Turkana livestock, while loss of woody cover results in destruction of riparian habitats.
Slow progress with integrated rural development programmes in Kenya's arid and semiarid lands
Authors: Adams M. E. 
Published: February 2007

AbstractIntegrated rural development programmes (IRDPs) in Kenya's Arid and Semiarid Lands (ASAL) arose out of a recognition that they had been neglected in the past and that levels of poverty, the need to increase production and the threat of environmental degradation merited special attention. The primary goal of the IRDP activities was to increase agricultural productivity, thereby contributing to food self‐sufficiency. This goal was reflected in the heavy concentration of resources in natural resource development. Such concentration was frequently at the cost of the development of human resources. Similarly, investment in physical infrastructure and in small‐scale industry was neglected. It was expected that IRDPs would be planned and implemented at the District‐level and would assist in the establishment of district administrative capacity. Participatory planning at the local level was considered a prerequisite to effective and sustainable integrated development. Sadly, IRDPs have been largely unsuccessful in both primary goals. While the reasons for failure are complex, it appears that two key issues stand out: (a) assumptions about the ability of government agricultural services to develop the potential of the ASAL were unrealistic, and (b) there was a lack of real devolution of power to district administrations, and more noticeably, to subdistrict levels. Despite the difficulties, the attraction of IRDPs to the ASAL remain strong. In a time of declining government budgets, they provide a means of getting funds to the district‐level and of catering for the special problems of semiarid environments. The continuing justification for IRDPs may be summarized as follows: (a) there is still a real problem of feeding a growing population in ASAL districts and in high agricultural potential zones; (b) without IRDPs in ASAL districts, standards of living would certainly fall; (c) this may prompt out‐migration from ASAL areas into high potential zones; (d) such out‐migration would occur in the context of increasing land pressure and rising unemployment in high‐potential areas; (e) IRDPs, by sustaining populations within ASAL districts, could contribute to food security in high‐potential areas; (f) IRDPs might also contribute to food security in ASAL districts themselves, by strengthening traditional production systems in these areas. The primary goal is to sustain the populations in ASAL districts by improving their food security. Although natural resource management is still necessary, there must be increasing attention paid to human resource development. Only then can a true transfer of power take place to ASAL districts, whereby their people effectively participate in overcoming and managing local problems.
Applications and limitations of chernobyl radiocaesium measurements in a carpathian erosion investigation, Poland
Authors: Higgitt D. L. , Froehlich W. , Walling D. E. 
Published: February 2007

AbstractThe bomb‐test fallout radionuclide caesium‐137, has found increasing application in geomorphological investigations of soil erosion. Comparatively little work has investigated the potential for using 134Cs and 137Cs derived from the 1986 Chernobyl accident. Results are reported from an agricultural foothill environment in the Beskidy Mountains of southern Poland. The high degree of spatial variability associated with Chernobyl fallout deposition poses considerable limitations on the potential for using radiocaesium measurements to elucidate detailed patterns of soil loss. Despite this problem, the redistribution of radiocaesium from field plots to terrace edges suggests a means for estimating the overall budgets for sediment transfer on cultivated slopes.
Spatial modelling of dryland salinization potential in Victoria, Australia
Authors: Ive J. R. , Walker P. A. , Cocks K. D. 
Published: February 2007

AbstractThe goal of the project discussed in this paper is to produce small‐scale maps of dryland salinization potential for Victoria, Australia; maps which putatively identify areas where salinization effects might be expected to worsen or where effects have yet to become evident. This paper assumes: (a) that current stream salinity levels can be modelled empirically using a relationship reported by Greig and Devonshire (1981), and (b) that a subset of these levels are indicative at an early stage of the maximum long‐term severity (meaning extensiveness) of proximate dryland salinization should water‐tables rise. This paper uses computer induction to relate modelled stream salinity to observed salinization and hence to dryland salinization potential.
Design and effectiveness of permeable infiltration dams in Burkina Faso
Authors: Vlaar J. C. J. 
Published: February 2007

AbstractThis paper reports on research in the Kongoussi Region of Burkina Faso, on permeable infiltration dams, which sought to establish their agricultural and hydrological impact, and to develop criteria for their most effective design. From these studies it appears that, depending on rainfall characteristics, the sorghum grain yields upstream of these dams were 0‐7 t ha−1 to 1‐7 t ha−1 higher than those obtained in valley bottom plots not benefitting from such structures. The difference in yield was most marked in relatively dry years. The hydrological impact appeared to be limited, and the impact on groundwater negligible. As for the design criteria, it appeared that the existing methods of Rodier‐Auvray and Rodier‐Ribstein for estimating runoff floods with a recurrence interval of ten years, are applicable to small catchment areas. Dimensions of a dam can thus be calculated. Other design criteria have been determined in a more qualitative manner and are also presented.
Political ecology of wildlife conservation in the Mt. Meru area of Northeast Tanzania
Authors: Neumann R. P. 
Published: February 2007

AbstractThe wildlife conservation problems in Tanzania are examined from a political ecology perspective. The analysis is historical, exploring the establishment of national parks under British colonial rule and the tightening of state control over access to resources at the expense of customary rights. Examples are presented from the Mt. Meru area of north‐eastern Tanzania. During the colonial period, the formal political debate over land and resource rights was conducted without the participation of African peasants. After independence the state continued to assert control over resource access unilaterally. As Meru peasants have effectively been shut out of the formal political process, their only recourse for defending the loss of access to natural resources is everyday forms of resistance, including de facto alliances with commercial poachers and ‘foot dragging’ in regards to compliance with conservation laws. Consequently there is little local support for current wildlife conservation policies on Mt. Meru and wildlife populations have declined in the 30 years since Arusha National Park was established there.
Land degradation and livestock production in Zimbabwe's communal areas
Authors: Scoones I. 
Published: February 2007

AbstractThis paper considers evidence of land degradation and its impact on livestock production systems in the communal areas of southern Zimbabwe. Various measures of rangeland degradation, using both primary and secondary production indicators, are examined. An apparent contradiction emerges between the high observed levels of soil erosion and the lack of impact on livestock production, as measured by population density trends, cattle production parameters, cumulative stocking levels and extraction rates. Farmers' observations of land degradation processes support the quantitative data. A possible resolution of the contradiction lies in an assessment of the spatial and temporal dimensions of degradation patterns; this points to the fact that current erosion is concentrated in areas that are not key grazing resources for cattle. The analysis suggests an agenda for degradation research that concentrates on evaluating the time span over which economic impacts of soil erosion are felt and assessing the spatial pattern of soil loss, with a special focus on key grazing resource patches.