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131.
This paper looks at the languages of empowerment and control as they are expressed by authors writing about indigenous knowledge. We performed a content analysis on CIKARD News, a newsletter dealing with the concept of indigenous knowledge. This concept has become increasingly prominent in the discourse of alternative development, addressing issues of ecological sustainability and the empowerment of the rural poor. However, mediated by institutions that perpetuate global and local power asymmetries, the empowering potential of indigenous knowledge may be bypassed. Instead, officials, researchers, and practitioners may utilize this knowledge for their own perceived ends, however good their intentions. In addition, there is already evidence that an indigenous knowledge approach is seen by major agencies as beneficial for integrating poorer populations into the global economy. Our analysis suggests that tensions persist among and within the writings of these authors between the desire to empower and the tendency for development to control rural populations.William E. O'Brien is currently a doctoral student in Environmental Design and Planning at the Virginia Polytechnic Institute and State University in Blacksburg, Virginia. His masters and bachelors degrees are both in Geography; the masters also from Virginia Tech, the bachelors degree from Radford University. His research interests center around the use of indigenous knowledge in pastoral development and agroforestry, particularly in East Africa. 相似文献
132.
Cornelia J. M. Almekinders 《Potato Research》1992,35(4):433-442
Summary Three similar field experiments with five cultivars were carried out to evaluate the effect of a 5-hour extension of the natural
daylength and a 3-hour night break on flowering and TPS production in the warm tropics. Shoot length, number of inflorescence
positions per plant and number of flowers per inflorescence varied considerably between the experiments. In each experiment,
the supplementary photoperiods delayed cessation of shoot growth and thereby increased the orders of branching and the number
of inflorescence positions per plant. The photoperiod treatments significantly increased the number of flowers at the last
produced inflorescence positions, but not at other ones. Pollen production and quality, berry set, seed set and 100-seed weight
were not affected by the photoperiod treatments. TPS production was characterized by variability in flowering and low and
variable seed production per flower. 相似文献
133.
Anamaria Irimia Emilia Csiszar Adina Coroabă Cristian-Dragoş Varganici Cornelia Vasile 《Fibers and Polymers》2016,17(10):1569-1578
A two step process was used for the modification of a cellulose/chitin mixed fibers: the first step was an alkali treatment with a NaOH solution (20 %), which was followed by the reaction with one of the reagents such as Nisopropylacrylamide, p-hydroxybenzoic acid, gallic acid, or eugenol. Both the samples activated with the alkali treatment and modified with chemicals were characterized by attenuated total reflectance Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy, scanning electron microscopy and thermal analysis. Results revealed the morphological and structural changes of the fiber surface after the surface grafting, which significantly altered the cellulose/chitin mixed fiber properties. Thermal analysis results showed an increase in the thermal stability of the treated samples. Antioxidant activity of cellulose/chitin mixed fibers modified with phenolic compounds showed that the efficiency depends on the chemical nature of phenolic compound. 相似文献
134.
M.W.I. SCHMIDT H. KNICKER P.G. HATCHER I. KOGEL-KNABNER 《European Journal of Soil Science》1997,48(2):319-328
The small organic matter content of mineral soils makes it difficult to obtain 13C and 15N nuclear magnetic resonance (NMR) spectra with acceptable signal-to-noise ratios. Subjecting such samples to hydrofluoric acid removes mineral matter and leads to a relative increase in organic material. The effect of treatment with 10% hydrofluoric acid on bulk chemical composition and resolution of solid-state 13C NMR spectra was investigated with six soils, some associated particle size fractions, plant litter and compost. The treatment enhanced the signal-to-noise ratio of the solid-state 13C NMR spectra. The improvement in spectrum quality was greatest in the clay fraction of soil contaminated with coal ash. The removal of paramagnetic compounds associated with the ash may be the main reason for the improvement. Based on total C, total N, C/N ratio and intensity distribution of the solid-state 13C NMR spectra, no changes in organic matter composition could be detected, except for a possible loss of carbohydrates. After treatment with HF, solid-state 15N NMR spectra of particle size fractions were obtained and indicated that the observable nitrogen is present mostly as peptides and free amino groups. Extraction with hydrofluoric acid is recommended as a routine treatment prior to solid-state 13C and 15N NMR on soil containing little C or N and soil samples containing paramagnetic compounds from natural or anthropogenic sources. 相似文献
135.
Klaus Kaiser Karin Eusterhues Cornelia Rumpel Georg Guggenberger Ingrid Kgel‐Knabner 《植物养料与土壤学杂志》2002,165(4):451-459
We tested the hypothesis whether organic matter in subsoils is a large contributor to organic carbon (OC) in terrestrial ecosystems and if survival of organic matter in subsoils is the result of an association with the soil mineral matrix. We approached this by analyzing two forest soil profiles, a Haplic Podzol and a Dystric Cambisol, for the depth distribution of OC, its distribution among density and particle‐size fractions, and the extractability of OC after destruction of the mineral phase by treatment with hydrofluoric acid (HF). The results were related to indicators of the soil mineralogy and the specific surface area. Finally, scanning electron microscopy combined with energy dispersive X‐ray spectroscopy (SEM‐EDX) was used to visualize the location of OC at mineral surfaces and associations with elements of mineral phases. The subsoils (B and C horizons) contained 40—50% of the soil OC including the organic forest floor layers. With increasing depth of soil profiles (1) the radiocarbon ages increased, and (2) increasing portions of OC were either HF‐soluble, or located in the density fraction d >1.6 g cm—3, or in the clay fraction. The proportions of OC in the density fraction d >1.6 g cm—3 were closely correlated to the contents of oxalate and dithionite‐citrate‐bicarbonate‐extractable Fe (r2 = 0.93 and 0.88, P <0.001). SEM‐EDX analyses suggested associations of OC with aluminum whereas silicon‐enriched regions were poor in OC. The specific surface area and the microporosity of the soil mineral matrix after destruction of organic matter were less closely correlated to OC than the extractable iron fractions. This is possibly due to variable surface loadings, depending on different OC inputs with depth. Our results imply that subsoils are important for the storage of OC in terrestrial ecosystems because of intimate association of organic matter with secondary hydrous aluminum and iron phases leading to stabilization against biological degradation. 相似文献
136.
A 1.6kb DNA fragment identified by random amplifiable polymorphic DNA differentiation (RAPD) from a Salmonella enterica serotype Typhimurium phage type DT104 isolate was used to investigate the prevalence of the region in 160 DT104 isolates, 83 other epidemiological important S. Typhimurium phage types and 20 strains selected from 17 other Salmonella serotypes. PCR screening tests using two different primer-sets derived from the RAPD fragment's nucleotide sequence showed that 76% of the 160 DT104 isolates investigated, including subtypes DT104A, DT104B, DT104B low, DT104H and DT104L, reacted positively. High sensitivity was shown for DT104 strains expressing at least the penta-resistance pattern ACSSuT (97% of 104 strains tested). DT104 susceptible strains showed only a sensitivity of 35% (17 strains tested). In contrast, 83% of the 83 strains from the other S. Typhimurium phage types reacted negatively. Strains from five out of the 17 other serotypes showed a positive signal with one primer-set. The other primer-set exhibited only a positive reaction with one S. Dublin isolate. The analysis of a 2415bp extended sequence revealed homologies to genes encoded by Escherichia coli O157:H7 prophages, suggesting that the described region contains genes of a prophage specific for DT104 and related phage types. 相似文献
137.
Agrostis stolonifera Huds cv.‘Penncross’ and cv.‘Cohansey’(bentgrass) were maintained as a golf-course putting green. Five herbicides were evaluated at normal (1 x) and three times normal (3 x) rates for Digitaria sanguinalis (L.) Scop (Crabgrass) control and influence on root development of sod. The herbicides were applied once (April), twice (April and August) and three times (April, June and August) annually. After application of 3 × rates, benfluralin (N-butyl-N-ethyl-2,6, dinitro-4-triflouromethylaniline) and chlorthal-dimethyl (2,3,5,6-tetrachloroterephthalic acid dimethyl ester) caused injury on both A. stolonifera cultivars. Shoot injury remained with repeated benfluralin treatments; however, injury was no longer apparent after the first application of chlorthal-dimethyl. Terbucarb (2,6-di-t-butyl-p-tolyl N-methylcarbamate) completely killed both cultivars during the second year of the study. Bensulide (N-[2-(0,0-di-isopropyldithiophosphoryl)ethyl]benzene sulphonamide) and siduron (N-(2-methylcyclohexyl)-N-phenylurea) did not influence shoot growth of either A. stolonifera cultivars. Chlorthaldimethyl, bensulide and siduron allowed excelent sod rooting in both cultivars. The 3 × rate of the three herbicides did affect rooting of ‘Cohansey’ cultivar during the second year of the study, as did the 1 × rate of benfluralin. The benfluralin injury did not persist from one treatment time to the next, even at 3 × rates. Terbucarb restricted root growth for the entire year. Bensulide and siduron provided acceptable D. sanguinalis control and acceptable A. stolonifera tolerance under golf-course green management and re-establishment with turf. 相似文献
138.
David S Galloway Rob L Coke Mark C Rochat Mary Anne G Radinsky John P Hoover James W Carpenter Jennifer J Hubbard Cornelia J Ketz-Riley 《Journal of zoo and wildlife medicine》2002,33(3):249-255
Two young (14-mo-old and 6-mo-old), unrelated, male African lions (Panthera leo) were presented to the Veterinary Teaching Hospitals of Oklahoma State University and Kansas State University with progressive ambulatory difficulty. In both cases, limited neurologic evaluation demonstrated pelvic limb paresis and ataxia with conscious proprioceptive deficits. Spinal imaging showed nearly identical lesions in both cases. Radiography and myelography demonstrated cervical stenosis secondary to atlantal (C1) malformation producing a dorsoventral deformity of the laminar arch with atlantoaxial spinal cord compression between the ventrally displaced laminar arch of the atlas and the underlying odontoid process of C2. Computed tomography of the atlanto-axial junction confirmed cervical stenosis and cord compression, showing flattening of the spinal cord between the laminar arch of C1 and the dens of C2. Decompressive surgery consisting of dorsal laminectomy of C1 was performed. Each lion demonstrated progressive improvement of neurologic status to recovery of normal ambulation after surgical intervention. Neurologic disease in large captive felids is rare; atlanto-axial spondylomyelopathy has not been reported previously. 相似文献
139.
K. SCHMIDT 《EPPO Bulletin》1996,26(1):117-122
In Germany, application of plant protection products by helicopter is only common in steep-sloped vineyards and in forests, where the use of conventional sprayers is nearly impossible. Because environment pollution, especially drift, is much higher than with ground equipment, the use of helicopters is subject to plant protection legislation as well as to air traffic regulations. BBA guidelines have been developed for application of plant protection products with aircraft. Each air-borne application must be based on a contract respecting these guidelines and must be reported to the proper authorities and announced to the public. The working airfields must be properly equipped and applications may only be performed under authorized weather conditions. The equipment of the aircraft must fulfil standards, especially for the spray tanks, the spray boom and the control devices, and so must the service stations on the ground. 相似文献
140.