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131.
The effect of twist level on the mechanical and thermal properties of nylon 66 and polyethylene terephthalate (PET) tyre cords
has been studied. Effects of the twist on some critical cord properties such as tensile properties, shrinkage, shrink force,
adhesion and fatigue have been evaluated. Breaking strength was decreased between 3.1 and 7.3 twist factor values, whereas
breaking elongation was increased, on both nylon 66 and polyester cords. The tensile behaviour of high twist factor PET is
similar to that of low twist factor nylon cords. This is an advantage for the possibility to get closer the properties of
different materials by adjusting theirs twist factors. The shrinkage values increase with increasing twist factor, whereas
shrinks force values decrease for greige nylons and polyester cords. Adhesion and fatigue resistance is increased with increasing
twist factors. 相似文献
132.
Nazli Dide Kutluk Yilmaz Huseyin Uzunbacak Miray Arli-Sokmen Riza Kaya 《Acta Agriculturae Scandinavica, Section B - Plant Soil Science》2018,68(6):546-554
Rhizomania, caused by Beet necrotic yellow vein virus (BNYVV), is one of the most devastating diseases on sugar beet throughout the world. A total of 235 BNYVV-infested soil samples taken from 29 provinces during the growing seasons of 2004–2005 and 2010–2011 were investigated for resistance-breaking properties of BNYVV isolates. BNYVV resistant (Rz1, Rz1?+?R2, Rz1?+?C48?+?minor genes) and susceptible (rz1) sugar beet cultivars were grown in the BNYVV-infested soils by the bait plant technique, and virus infection was evaluated based on disease symptom and DAS-ELISA. Of the soil samples tested, 57.4% produced infection in the roots of sugar beet cultivar (cv.) containing the Rz1 gene, 51.9% in cv. carrying the Rz1?+?Rz2 and 18.9% in cv. carrying the Rz1?+?C48?+?minor genes. Also, the presence of Beet soil-borne virus (BSBV) was evaluated by TAS-ELISA. Additionally, the presence of BNYVV RNA-5 component was investigated by RT–PCR using the primers specific for p26 coding region. Our results revealed that BNYVV isolates compromising resistance genes are highly common and widespread in sugar beet production areas in Turkey, and it seems unlikely that BSBV and/or RNA-5 were directly involved in RB-event. 相似文献
133.
Major flavonoids in grape seeds and skins: antioxidant capacity of catechin, epicatechin, and gallic acid 总被引:1,自引:0,他引:1
Grape seeds and skins are good sources of phytochemicals such as gallic acid, catechin, and epicatechin and are suitable raw materials for the production of antioxidative dietary supplements. The differences in levels of the major monomeric flavanols and phenolic acids in seeds and skins from grapes of Vitis vinifera varieties Merlot and Chardonnay and in seeds from grapes of Vitis rotundifolia variety Muscadine were determined, and the antioxidant activities of these components were assessed. The contribution of the major monomeric flavonols and phenolic acid to the total antioxidant capacity of grape seeds and skins was also determined. Gallic acid, monomeric catechin, and epicatechin concentrations were 99, 12, and 96 mg/100 g of dry matter (dm) in Muscadine seeds, 15, 358, and 421 mg/100 g of dm in Chardonnay seeds, and 10, 127, and 115 mg/100 g of dm in Merlot seeds, respectively. Concentrations of these three compounds were lower in winery byproduct grape skins than in seeds. These three major phenolic constituents of grape seeds contributed <26% to the antioxidant capacity measured as ORAC on the basis of the corrected concentrations of gallic acid, catechin, and epicatechin in grape byproducts. Peroxyl radical scavenging activities of phenolics present in grape seeds or skins in decreasing order were resveratrol > catechin > epicatechin = gallocatechin > gallic acid = ellagic acid. The results indicated that dimeric, trimeric, oligomeric, or polymeric procyanidins account for most of the superior antioxidant capacity of grape seeds. 相似文献
134.
Restoration of degraded lands in urban areas increases the ecologic, aesthetic and economic value of these areas and contributes to quality of life in cities. This study explores public attitudes towards restoration of a derelict urban streamside corridor. Data for this study were collected using a social survey among users and neighbourhood residents of the Çayboyu area in Isparta, Turkey. The survey compared the previous and present situation of the survey site in order to reveal the influence of stream restorations on public perception and use of derelict urban landscapes. The results identified a dramatic change in public perceptions between the previous and present situation of the area. Following the restoration works, the Çayboyu area has become one of the most popular and intensively used green spaces in the city. The survey results suggest that restoration of derelict lands increases the value of such areas for people and enhances their uses for recreational purposes in urban areas. Therefore, it is vital that urban planners and local authorities should encourage restoration of derelict and unused urban areas and preserve them as green spaces to meet the amenity needs of urban people. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
135.
Yaralioglu-Gurgoze S Cetin H Cen O Yilmaz S Atli MO 《Veterinary journal (London, England : 1997)》2005,170(1):135-137
Endometritis is an important factor in infertility. Free radicals play an important role in endometritis and we have investigated their possible role and scavenging systems in endometritis in purebred Arabian mares. The plasma concentration of malondialdehyde (MDA) and erythrocyte glutathione peroxidase (GPx) activity were compared in healthy mares and in mares with endometritis. The level of MDA was significantly increased while GPx activity was decreased in the mares with endometritis. Our findings support the notion that GPx is consumed by increased lipid peroxidation in purebred Arabian mares affected with endometritis. 相似文献
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139.
Kaleta EF Blanco Peña KM Yilmaz A Redmann T Hofheinz S 《DTW. Deutsche tier?rztliche Wochenschrift》2007,114(7):260-267
Birds of the order Psittaciformes are - besides chickens, turkeys and other birds - also susceptible to infection with avian influenza A viruses (AIV) and succumb following severe disease within one week. Published data prove that various parakeets, amazons, cockatoos, African grey parrots and budgerigars (genera Barnardius, Psittacula, Cacatua, Eolophus, Amazona, Myiopsitta, Psittacus and Melopsittacus) were found dead following natural infections. Natural infections of highly pathogenic avian influenza viruses (HPAIV) of the haemagglutinin subtypes H5 and H7 cause severe disease and high rates of mortality. Experimental transmission studies with AlVs of the subtypes H5 and H7 confirm these data. Viruses of the subtypes H3N8, H4N6, H4N8, H11N6 and H11N8 may cause also clinical signs and occasionally losses in naturally infected psittacine birds. Clinical signs and losses were also noted following experimental infection of budgerigars with a H4N6 virus. In the EU and in other countries, vaccination of exposed exotic and rare birds and poultry is a possible and an acceptable measure to provide protection. Currently, the EU Commission accepts inactivated adjuvanted vaccines whereas in some other countries recently developed vector vaccines are applied. However, birds remain susceptible during the time interval between application of any vaccine and the development of immunity. This critical period can be bridged with antiviral drugs. Our in ovo studies demonstrate that the neuraminidase inhibitor oseltamivir is non-toxic for chicken embryos at concentrations of 0.1, 1.0 and 10.0 mg/kg body weight. These dosages prevented entirely the replication of a HPAIV of the subtype H7N1 when this drug is given shortly prior to, simultaneously or soon after inoculation of chicken embryos with this AIV. Thus, we speculate that exposed valuable birds such as psittacines at risk can be successfully treated. 相似文献
140.
OBJECTIVE: To characterise the lipid profiles in dogs with parvoviral enteritis. METHODS: Blood was collected before treatment from 30 dogs that fulfilled the criteria for severe sepsis including hypo- or hyperthermia, hypotension, leucopenia, thrombocytopenia and evidences of organ dysfunction. Canine parvovirus was detected by haemagglutination and indirect fluorescence antibody tests in the faeces. Twenty control dogs were also enrolled on the basis of normal physical examination results, complete blood count and serum biochemistry profiles. RESULTS: Tachycardia, tachypnoea, hypotension, leucopenia, thrombocytopenia and increased serum markers of tissue injury (alanine aminotransferase, creatinine kinase myocardial isoenzyme [CK-MB], blood urea nitrogen and creatinine) were observed in dogs with parvoviral enteritis. Serum total cholesterol, high-density lipoprotein cholesterol and low-density lipoprotein cholesterol levels were lower, but serum triglyceride level was higher in dogs with parvoviral enteritis than those in control dogs (P<0.001). Circulating tumour necrosis factor alpha correlated negatively with total cholesterol (r=-0.979; P<0.001) but positively with triglyceride (r=0.953; P<0.001) in dogs with parvoviral enteritis. Serum total cholesterol and high-density lipoprotein cholesterol levels were lower in non-survival (n=9) dogs than in survival dogs (n=21, P<0.001). CLINICAL SIGNIFICANCE: Serum total cholesterol and high-density lipoprotein cholesterol levels decreased, but serum triglyceride level increased in dogs with parvoviral enteritis. Low serum total cholesterol and high-density lipoprotein cholesterol levels may be used as an index of the severity of parvoviral enteritis. 相似文献