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101.
Seed quality is one of the important objectives in cotton production and breeding. Seed-coat fragments (SCFs) and motes are the main impurities in lint cotton and are major concerns in the textile industry. A 2-year study was conducted to compare 10 cotton (Gossypium hirsutum L.) cultivars for the number of SCFs, motes, and resistance to loading force (RL).  相似文献   
102.
This study examined the effects of matrix (PVA and Si) on the properties of TEMPO-treated nanocomposites preparing from different pulp sources (Kraft and NaBH4 treated Kraft). Chemical characterization and crystallization were determined via FT-IR, thermal stability via TGA and morphological alterations via SEM. UTM and DTMA were used to measure the Young’s and storage moduli. The real and imaginary parts of permittivity and electric modulus were evaluated using an impedance analyzer. After interaction, prominent vibrations and alteration of crystallinity were seen. Storage and Young’s moduli decreased after Si and PVA interaction. The Si-TOCN films showed higher permittivity properties and all of the films followed a similar trend of significantly dropping ε' and ε'' values at high frequency. The PVA-TOCN films had mechanical advantages at room temperature compared to the Si-TOCN films. However, the Si-TOCN films had better thermomechanical properties at high temperatures. NaBH4 revealed favorable effects on mechanical properties of the films.  相似文献   
103.
Two haplotypes of the pathogen, ‘Candidatus Liberibacter solanacearum,’ (Lso) and four haplotypes of the insect vector, Bactericera cockerelli, are associated with zebra chip disease of potato. Whether disease severity or incidence is influenced by pathogen or insect haplotype is poorly understood. The role of Lso ‘A’ and ‘B,’ transmitted by three haplotypes of B. cockerelli, on disease severity and incidence in eight potato cultivars was analyzed. Both haplotypes of Lso induced tuber symptoms. In general, Lso B caused higher incidence of symptoms, and greater reduction in tubers compared with Lso A. Lso B was associated with more severe tuber symptoms, producing fewer mild or moderate tuber symptoms. Lso A was associated with less severe tuber symptoms, despite being able to induce severe symptoms. Disease incidence, tuber yield, and symptom severity ratings were not dependent upon the psyllid haplotype transmitting the pathogen, suggesting that pathogen, not insect haplotype affects Lso transmission.  相似文献   
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106.
Rainbow trout Oncorhynchus mykiss and mirror carp Cyprinus carpio were slaughtered by either percussion or asphyxiation. For determination of the physical (texture value) and biochemical quality attributes [pH, lactic acid, total volatile basic nitrogen (TVB-N), and malondialdehyde (MDA) values] of trout and carp, the fish were filleted immediately (within 2 h), 12 h after harvest (pre-rigor), 24 and 36 h after harvest (in-rigor), and finally 48 and 60 h after harvest (post-rigor). For microbiological quality attribute (mesophilic and psychrophilic bacteria count) analyses, the fish were filleted immediately (within 2 h) after harvest (pre-rigor), 24 h after harvest (in-rigor) and 48 and 72 h after harvest (post-rigor). By percussion slaughtering followed by pre-rigor filleting, it was possible to process rainbow trout and mirror carp without inflicting excessive handling stress. Percussion slaughter delayed onset of rigor and the percussion-slaughtered fish exhibited a long pre-rigor period (≈24 h), giving plenty time for pre-rigor processing. Percussion slaughtering and pre-rigor filleting of fish was considered to be superior to the traditional asphyxiation slaughtering with respect to texture, TVB-N and MDA attributes.  相似文献   
107.
Argyrosomus regius (3.0 ± 0.9 g) were exposed to different concentrations of ammonia in a series of acute toxicity tests by the static renewal method at three temperature levels (18, 22 and 26°C) at a pH of 8.2. Low temperature clearly increased the tolerance of the fish to total ammonia nitrogen (TAN) and unionized ammonia (NH3) (P < 0.05). While the 96‐h LC50 values of TAN were 19.79, 10.39 and 5.06 mg L?1, the 96‐h LC50 of NH3 were 1.00, 0.70 and 0.44 mg L?1 at 18, 22 and 26°C respectively. The safe levels of NH3 for A. regius was estimated to be 0.10, 0.07 and 0.04 mg L?1 at 18, 22 and 26°C respectively (P < 0.05). This study clearly indicates that A. regius is more sensitive to ammonia than other marine fish species cultured on the Mediterranean and Eastern Atlantic coasts.  相似文献   
108.
An isolated non-working trout heart, cannulated through the coronary artery and perfused with oxygenated saline with a coronary pressure head of 3.0 kPa has been used in this study. Effects on the coronar resistance of catecholamines, thromboxanes (TXs) and prostacyclin (PGI2) were analyzed. The effects of PGI2 and TXs in presence of noradrenaline were also evaluated. Both adrenaline and noradrenaline vasoconstrict the trout coronary system, noradrenaline being more potent than adrenaline. TXA2 induces 45% vasoconstriction at 10−6M, while TXB2 at the same concentration is a slight vasodilator. PGI2 acts as a weak vasodilator (about 20% decrease in resistance at 10−6M). In presence of 10−7M noradrenaline, 10−8M TXA2 reduces the vasoconstriction induced by the catecholamine alone from 60% to about 15%. Under similar conditions, 10−9M PGI2 potentiates the vasoconstrictive response induced by noradrenaline while a much higher PGI2 concentration (10−6M) completely abolishes the vasoconstriction. The β-receptor antagonist propranolol induces vasoconstriction, and 10−9M PGI2 in presence of propranolol further increases the vasoconstriction. The α-receptor antagonist phentolamine induces vasodilation and 10−9M PGI2 does not affect coronary resistance induced by phentolamine. These results imply a possible interaction between noradrenaline and prostanoids (TXs and PGI2) in the vasomotion of trout coronary system.  相似文献   
109.
We identified clinical disorders of all 200 city-dwelling cart pulling male camels attending the Veterinary Teaching Hospital, University of Agriculture, Faisalabad, Pakistan during a 7-year period (1993–1999). Data were collected prospectively on a predesigned form and collated. Diagnoses of different diseases/disorders were based on clinical examination supplemented with relevant laboratory tests. A total of 463 entries of 34 different clinical diseases/disorders were recorded. Sarcoptic mange (35% of 200 camels) followed by anhidrosis (23%) and trypanosomosis (19%) were the three most frequently encountered disorders. The body system most often involved was the integument (31%) followed by gastrointestinal (21%), locomotory (12%), thermoregulatory (6%), blood (6%), urogenital (6%), lymphatic (3%), nervous (3%), respiratory (3%) and ocular (3%).  相似文献   
110.
The aim of study was to investigate the effect of genotype on carcass measurements and meat quality characteristics of purebred Hair Goat, Saanen × Hair Goat (F1 and B1) kids under an intensive production system. In total, 24 kids were slaughtered at the age of approximately 133 days. Kids were fattened for 56 days immediately after weaning. Hot carcass weights were 6.78, 7.61 and 7.02 kg and dressing percentages were 49.71, 49.27 and 48.78%, respectively ( P  > 0.05). Differences between genotypes for carcass measurements and indexes were not significant. Effect of genotype on pH measurements, drip loss, water holding capacity, cooking loss and Warner Bratzler shear force values were not significant. Meat lightness values at 0 h, 1 h and 1 day after cutting were higher in crossbred kids than Hair Goat kids ( P  < 0.05). Redness value was significantly higher in meat samples of Hair goat kids at 0 h, 1 h and 1 day measurements ( P  < 0.05). Kid genotype had no significant effect on meat sensory characteristics, except tenderness. Panelists gave lower scores for meat tenderness to F1 and B1 crosses compared to purebred Hair Goat kids. In conclusion, higher meat lightness values of crossbred kids, at particularly B1 level, might have a positive effect on the consumer choices.  相似文献   
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