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91.
Marlène Elias 《Agroforestry Systems》2013,87(1):203-216
This article examines the role of humans in shaping a shea tree (Vitellaria paradoxa C.F. Gaertn.) population in Prata, central-west Burkina Faso. Four management regimes or land uses were considered: fields cultivated by indigenous Gurunsi farmers, fields cultivated by migrant Moose farmers, fallows, and bush lands. The structure of the shea population differed between Gurunsi and Moose fields and between these fields and fallow and bush lands. The size class distribution of V. paradoxa in fallows and bush lands was skewed towards the lower classes and the slope of the distributions was negative and significant, indicating the occurrence of recruitment. In comparison, Gurunsi fields carried young and mature trees with 95 % of individuals in the 15.5–90 cm range, whereas Moose fields carried no specimen with dbh <16.5 cm. The slope of the size class distribution was slightly negative for Gurunsi fields and slightly positive for Moose fields, but non significant in both cases. Vitellaria paradoxa densities did not significantly differ between Gurunsi (35 stems/ha) and Moose (26 stems/ha) fields, but were higher in fallows (172 stems/ha) and in the bush (161 stems/ha) than in cultivated fields. Nearest neighbour distances were progressively greater from uncultivated fields to Gurunsi and finally Moose fields, whereas shea trees were increasingly aggregated from Moose to Gurunsi fields to fallows and bush lands. In Prata, shea tree management is thus associated with ethnicity and/or with a host/migrant status that confers different farm sizes and levels of tenure security to farming households. Gurunsi and Moose farmers cited productivity, spacing and shading effects as the main factors influencing their decision to conserve specific shea trees in their fields. Results signal favorable prospects for V. paradoxa regeneration in Prata’s fallows and bush lands and to a lesser extent in Gurunsi fields. 相似文献
92.
Ajay Kumar Elias M. Elias Farhad Ghavami Xin Xu Shalu Jain Frank A. Manthey Mohamed Mergoum Mohammed S. Alamri Penny M.A. Kianian Shahryar F. Kianian 《Journal of Cereal Science》2013
Gluten strength is an important characteristic, determining the end product quality of durum wheat semolina. To identify the genetic basis of gluten strength in North Dakota durum cultivars, a doubled haploid population was developed from the cross of a weak gluten cultivar ‘Rugby’ and a strong gluten cultivar ‘Maier’. A framework linkage map consisting of 228 markers was constructed and used with phenotypic data on gluten strength (measured by sedimentation volume) to conduct single- and two-locus QTL analyses. Only one consistent QTL (QGs.ndsu-1B) contributing up to 90% of the phenotypic or 93% of the genotypic variation was detected on 1BS. No QTL × QTL or QTL × environment interactions were observed. The QGs.ndsu-1B was flanked by two DArT markers which were converted to STS markers and used along with SSR and EST-SSRs to develop a map of 1BS. QTL analysis delineated QGs.ndsu-1B in a 7.3 cM region flanked by an STS marker (STS-wPt2395) and a SSR marker (wmc85). The adapted background of this material and availability of PCR-based markers closely associated with this locus represent invaluable resources for marker-assisted introgression of gluten strength into other durum wheat varieties. A single QTL segregating in this population also makes it an ideal target for map-based cloning. 相似文献
93.
AbstractCASE HISTORY: One 4.5-month-old male Border Collie cross presented with aggression and seizures in October 2006. A 16-month-old, female, spayed Border Collie cross presented with hypersalivation and a dropped jaw and rapidly became stuporous in September 2007. The dogs were littermates and developed acute neurological signs 5 and 27 days, respectively, after vaccination with different modified live vaccines containing canine distemper virus.HISTOPATHOLOGICAL FINDINGS: Sections of brain in both dogs showed evidence of encephalitis mainly centred on the grey matter of brainstem nuclei, where there was extensive and intense parenchymal and perivascular infiltration of histiocytes and lymphocytes. Intra-nuclear and intra-cytoplasmic inclusions typical of distemper were plentiful and there was abundant labelling for canine distemper virus using immunohistochemistry.DIAGNOSIS: Post-vaccinal canine distemper.CLINCIAL RELEVANCE: Post-vaccinal canine distemper has mainly been attributed to virulent vaccine virus, but it may also occur in dogs whose immunologic nature makes them susceptible to disease induced by a modified-live vaccine virus that is safe and protective for most dogs. 相似文献
94.
This study aimed to evaluate the effects of increasing levels of β-glucanase on the modulation of jejunal mucosa-associated microbiota in relation to nutrient digestibility and intestinal health of pigs fed diets with 30% corn distiller’s dried grains with solubles and xylanase. Forty pigs at 12.4 ± 0.5 kg body weight (BW) were allotted in a randomized complete block design with initial BW and sex as blocks. Dietary treatments consisted of a basal diet with xylanase (1,500 endo-pentosanase units [EPU]/kg) and increasing levels of β-glucanase (0, 200, 400, and 600 U/kg) meeting nutrient requirements and fed to pigs for 21 d. Blood samples were collected on day 19. On day 21, all pigs were euthanized to collect intestinal tissues and digesta. Tumor necrosis factor-alpha, interleukin (IL)-6, and malondialdehyde were measured in the plasma and mid-jejunal mucosa. Viscosity was determined using digesta from the distal jejunum. Ileal and rectal digesta were evaluated to determine apparent ileal digestibility (AID) and apparent total tract digestibility (ATTD) of nutrients. Mucosa samples from the mid-jejunum were utilized for microbiota sequencing. Data were analyzed using the MIXED procedure on SAS 9.4. Overall, increasing dietary β-glucanase tended to increase (linear; P = 0.077) the average daily gain of pigs. Increasing dietary β-glucanase affected (quadratic; P < 0.05) the relative abundance of Bacteroidetes, reduced (linear; P < 0.05) Helicobacter rappini, and increased (linear, P < 0.05) Faecalibacterium prausnitzii. β-Glucanase supplementation (0 vs. others) tended to increase (P = 0.096) the AID of crude protein in the diet, whereas increasing dietary β-glucanase tended to increase (linear; P = 0.097) the ATTD of gross energy in the diet and increased (linear; P < 0.05) the concentration of IL-6 in the plasma of pigs. In conclusion, increasing β-glucanase up to 600 U/kg feed in a diet containing xylanase (1,500 EPU/kg) modulated mucosa-associated microbiota by increasing the relative abundance of beneficial bacteria and reducing potentially harmful bacteria. Furthermore, increasing β-glucanase up to 600 U/kg feed in a diet containing xylanase (1,500 EPU/kg feed) enhanced the status of the intestinal environment and nutrient utilization, as well as reduced systemic inflammation of pigs, collectively resulting in moderate improvement of growth performance. Supplementing β-glucanase at a range of 312 to 410 U/kg with xylanase at 1,500 EPU/kg feed showed the most benefit on jejunal mucosa-associated microbiota and reduced systemic inflammation of pigs. 相似文献
95.
Cobalt ferrite nanocrystals were prepared from an aqueous solution containing metal nitrates and various of concentrations of poly(vinyl pyrrolidone), followed by calcinations temperature. X-ray diffraction (XRD) analysis was performed to determine the degree of crystallinity of the ferrite nanoparticles. By transmission electron microscopy (TEM), the morphology and average particle size of the cobalt ferrite nanoparticles were evaluated which had good agreement with XRD results. Fourier transform infrared spectroscopy (FT-IR) suggested the presence of metal oxide bands in all samples as well as the effective elimination of organic constituents after calcinations. Vibrating sample magnetometer (VSM), was utilized to evaluate the magnetic properties of the cobalt ferrite nanoparticles. 相似文献
96.
97.
Mastitis is the most common infectious disease affecting dairy cattle; in addition, it remains the most economically important disease of dairy industries around the world. Streptococcus agalactiae, a contagious pathogen associated with subclinical mastitis, is highly infectious. This bacterium can cause an increase in bulk tank bacterial counts (BTBC) and bulk tank somatic cell counts (BTSCC). The microbiological identification of S. agalactiae in samples from bulk tanks is an auxiliary method to control contagious mastitis. Thus, there are some limitations for time-consuming cultures or identification methods and additional concerns about the conservation and transport of samples. Bulk tank samples from 247 dairy farms were cultured and compared through polymerase chain reaction (PCR), directed to 16S rRNA genes of S. agalactiae, followed by BTBC and S. agalactiae isolation. The mean value of BTBC was 1.08×10(6) CFU mL(-1) and the bacterium was identified through the microbiological method in 98 (39.7%; CI(95%)=33.8-45.9%) and through PCR in 110 (44.5%; CI(95%)=38.5-50.8%) samples. Results indicated sensitivity of 0.8571±0.0353 (CI(95%)=0.7719-0.9196) and specificity of 0.8255±0.0311 (CI(95%)=0.7549-0.8827). The lack of significant difference between microbiological and molecular results (κ=0.6686±0.0477 and CI(95%)=0.5752-0.7620) indicated substantial agreement between the methods. This suggests that PCR can be used for bulk tank samples to detect contagious mastitis caused by S. agalactiae. 相似文献
98.
J. L. Gonzalez-Hernandez P. K. Singh M. Mergoum T. B. Adhikari S. F. Kianian S. Simsek E. M. Elias 《Euphytica》2009,166(2):199-206
Stagonospora nodorum blotch (SNB) is an important foliar disease of durum wheat (Triticum turgidum var. durum) worldwide. The combined effects of SNB and tan spot, considered as components of the leaf spotting disease complex,
result in significant damage to wheat production in the northern Great Plains of North America. The main objective of this
study was the genetic analysis of resistance to SNB caused by Phaeosphaeria nodorum in tetraploid wheat, and its association with tan spot caused by Pyrenophora tritici-repentis race 2. The 133 recombinant inbred chromosome lines (RICL) developed from the cross LDN/LDN(Dic-5B) were evaluated for SNB
reaction at the seedling stage under greenhouse conditions. Molecular markers were used to map a quantitative trait locus
(QTL) on chromosome 5B, explaining 37.6% of the phenotypic variation in SNB reaction. The location of the QTL was 8.8 cM distal
to the tsn1 locus coding for resistance to P. tritici-repentis race 2. The presence of genes for resistance to both SNB and tan spot in close proximity in tetraploid wheat and the identification
of molecular markers linked to these genes or QTLs will be useful for incorporating resistance to these diseases in wheat
breeding programs. 相似文献
99.
İlhami Gülçin Riad Elias Akçahan Gepdiremen Khalil Taoubi Ekrem Köksal 《Wood Science and Technology》2009,43(3-4):195-212
Recently, a number of studies on health benefits associated with natural compounds have been demonstrated. Phenolics in fruits, vegetables, herbs and spices possess potent antioxidant, anti-inflammatory, antimutagenic and anticarcinogenic activities. The fringe tree (Chionanthus virginicus) is used as a raw material by pharmaceutical industries for the preparation of homeopathy tinctures. The potential antioxidant activities of two secoiridoids from root bark of fringe tree (Chionanthus virginicus L.) were investigated to evaluate their potential value as the natural products for foods or cosmetic applications. In this study, antioxidant activities were measured by 2,2-azino-bis(3-ethylbenzthiazoline-6-sulfonic acid) (ABTS) radical scavenging, 1,1-diphenyl-2-picryl-hydrazyl free radical (DPPH·) scavenging, superoxide anion (O 2 ·? ) radical scavenging, total antioxidant activity, reducing activity, hydrogen peroxide (H2O2) scavenging and ferrous metal chelating activity assays. These secoiridoids, as antioxidants neutralized the activities of radicals and inhibited the peroxidation reactions of linoleic acid emulsion. Total antioxidant activity was measured according to ferric thiocyanate method. Butylated hydroxyanisole (BHA), butylated hydroxytoluene (BHT), α-tocopherol and trolox, a water-soluble analog of tocopherol, were used as the reference antioxidant compounds. Ligustroside (3.70 × 10?3 M) and oleuropein (3.80 × 10?3 M) showed 71.9, 82.4, 80.7 and 90.4% inhibition on lipid peroxidation of linoleic acid emulsion, at the concentrations of 10 and 20 μg/mL. On the other hand, 20 μg/mL of standard antioxidant such as α-tocopherol (4.64 × 10?3 M), trolox (7.98 × 10?3 M), BHA (10.08 × 10?3 M) and BHT (9.06 × 10?3 M) exhibited 61.5, 29.8, 74.4 and 71.2% inhibition on peroxidation of linoleic acid emulsion, respectively. In addition, ligustroside and oleuropein had effective DPPH·, ABTS·+ and superoxide anion radicals scavenging, hydrogen peroxide scavenging, total reducing power and metal chelating on ferrous ions activities. Also, those various antioxidant activities were compared to BHA and BHT, α-tocopherol and trolox that are references antioxidants. 相似文献
100.
Saira Khan Clauvis Nji Tizi Taning Elias Bonneure Sven Mangelinckx Guy Smagghe Mohammad Maroof Shah 《Phytoparasitica》2017,45(1):113-124
With the aim of selecting potential botanical insecticides, seven plant extracts (Daphne mucronata (Family: Thymelaeaceae), Tagetes minuta (Asteraceae), Calotropis procera (Apocynaceae), Boenninghausenia albiflora (Rutaceae), Eucalyptus sideroxylon (Myrtaceae), Cinnamomum camphora (Lauraceae) and Isodon rugosus (Lamiaceae)) were screened for their toxic effects against four important agricultural pest insects, each representing a separate insect order; pea aphids of Acyrthosiphon pisum (Hemiptera), fruit flies of Drosophila melanogaster (Diptera), red flour beetles of Tribolium castaneum (Coleoptera), and armyworms of Spodoptera exigua (Lepidoptera). Aphids were the most susceptible insect with 100% mortality observed after 24 h for all the plant extracts tested. Further bioassays with lower concentrations of the plant extracts against aphids, revealed the extracts from I. rugosus (LC50 36 ppm and LC90 102 ppm) and D. mucronata (LC50 126 ppm and LC90 198 ppm) to be the most toxic to aphids. These most active plant extracts were further fractionated into different solvent fractions on polarity basis and their insecticidal activity evaluated. While all the fractions showed considerable mortality in aphids, the most active was the butanol fraction from I. rugosus with an LC50 of 18 ppm and LC90 of 48 ppm. Considering that high mortality was observed in aphids within 24 h of exposure to a very low concentration of the butanol fraction from I. rugosus, we believe this could be exploited and further developed as a potential plant-based insecticide against sucking insect pests, such as aphids. 相似文献