Properties of stick-slip stage of yarn pull-out in para-aramid woven fabric

The aim of this study was to understand stick-slip properties of para-aramid woven fabrics. For this reason, pullout test was conducted on para-aramid Kevlar®29 and Kevlar®129 woven fabrics. The stick-slip and accumulative retraction force regions were defined based on the force-displacement curve. It was found that the stick-slip force and accumulative retraction force depended on fabric density and the number of pulled ends in the fabric. Stick-slip force in the multiple yarn pull-out test was higher than those of the single yarn pull-out test. Stick-slip force in single and multiple yarn pull-out tests in the dense K29 fabric were higher than those of the loose K129 fabric. In addition, long fabric samples showed high stick-slip force compared to that of the short fabric samples. On the other hand, the amount of stick-slip force was related to the number of interlacement points in the fabric whereas the amount of accumulative retraction force was related to fabric structural response.     

Polymeric nanoparticles as an oral delivery system for biocontrol agents for the brushtail possum (Trichosurus vulpecula)

Abstract

AIM: To investigate polymeric nanoparticles as an oral delivery system for protein biocontrol agents for control of the brushtail possum, Trichosurus vulpecula.

METHODS: Insulin-loaded poly(ethyl 2-cyanoacrylate) (PECA) nanoparticles were prepared using interfacial polymerisation, and characterised for size, zeta potential, and efficiency of encapsulation of insulin. In-vitro release of insulin-loaded PECA nanoparticles was quantified using reverse-phase highpressure liquid chromatography (HPLC). The in-vivo pharmacokinetics of insulin in PECA nanoparticles was investigated following I/V administration, and when injected directly into the caecum alone or in conjunction with the permeation enhancer EDTA. Blood samples were collected at intervals from ?5 to 180 minutes, and the concentration of insulin in plasma was quantified using a radioimmunoassay (RIA) validated for possum plasma.

RESULTS: Poly(ethyl 2-cyanoacrylate) nanoparticles were produced with a uniform particle size of 200–300 nm, and the mean entrapment of insulin was 78%. In-vitro release of insulin from the PECA nanoparticles was controlled, although incomplete, and approximately 30% of the insulin remained entrapped. The bioavailability of insulin when administered in a PECA nanoparticulate formulation injected directly into the caecum was <1%, and was not increased by addition of the permeation enhancer.

CONCLUSIONS: The nanoparticulate formulations investigated as part of this study resulted in low bioavailability of the peptide insulin in the brushtail possum.     

Prevalence and Characterization of Coagulase Positive Staphylococci Isolated from Salted Anchovy

A total of 100 salted anchovy samples were used to investigate the prevalence of S. aureus and other coagulase positive Staphylococci (CPS) as well as to determine the methicillin (MR) and antibiotic resistance (AR) profile, the presence of Panton-Valentine leukocidine (PVL) toxin gene (lukS/F-PV), slime factor properties (SFP), and the genotypic relatedness of the isolates. Agar disc diffusion assay (ADDA) and microdilution broth susceptibility test (MDBST) were applied to compare the specificity and sensitivity of the MR detection methods. A total of 41 CPS isolates were detected at the 10² and 10³ CFU/g levels in contrast to S. aureus. The 16S rRNA (genus specific) was detected in all the isolates in contrast to nuc (species-specific) and lukS/F-PV genes. A total of 16/41 isolates were found to be MR by using the three methods. Polymerase chain reaction (PCR) assay was a more sensitive and reliable method for the detection of MR isolates. The antibiotic resistance rates were 75.60, 73.17, 51.21, 31.70, 12.19, and 4.87% to penicillin, ampicillin, tetracycline, erythromycin, ciprofloxacin, and clindamycin, respectively. All the isolates were sensitive to gentamicin and vancomycin. The SFP were determined in all the isolates by using Congo Red agar, and 20 different genotypes were determined by using randomly amplified polymorphic DNA (RAPD)-PCR assay.     

Integrated Use of Nitrogen Fertilization and Microbial Inoculation: Change in the Growth and Chemical Composition of White Cabbage

Field experiments were conducted to evaluate the impact of seed and seedling inoculation by plant growth promoting rhizobacteria (PGPR) on nitrogen use efficiency, growth, yield, and chemical composition of cabbage at varying levels of nitrogen (N). Data revealed that N alone or in combination with PGPR either as seed or seedling inoculation significantly improved growth, yield, and nutrients of cabbage. PGPR inoculations were more efficient than non-inoculated controls in terms of yield and yield parameters. This study showed that seed and seedling inoculation increased yield and yield parameters as well as chlorophyll reading value and stomatal conductance versus controls. Applications of mineral fertilizers with microbial applications save 25% of mineral fertilizers yet give 33% more yield versus full doses of mineral application without microbial applications. Both seed and seedling treatments increased the nitrogen use efficiency (NUE) rates by 45, 53, 58, 45, and 40%, and 49, 59, 68, 69, 60, and 55%, respectively.     

Effect of contact angle hysteresis on the removal of the sporelings of the green alga Ulva from the fouling-release coatings synthesized from polyolefin polymers

Wettability is one of the surface characteristics that is controlled by the chemical composition and roughness of a surface. A number of investigations have explored the relationship between water contact angle and surface free energy of polymeric coatings with the settlement (attachment) and adhesion strength of various marine organisms. However, the relationship between the contact angle hysteresis and fouling-release property is generally overlooked. In the present work, coatings were prepared by using commercial hydrophobic homopolymer and copolymer polyolefins, which have nearly the same surface free energy. The effects of contact angle hysteresis, wetting hysteresis, and surface free energy on the fouling-release properties for sporelings of the green alga Ulva from substrates were then examined quantitatively under a defined shear stress in a water channel. The ease of removal of sporelings under shear stress from the polymer surfaces was in the order of PP>HDPE>PPPE>EVA-12 and strongly and positively correlated with contact angle and wetting hysteresis; i.e., the higher the hysteresis, the greater the removal.     

Effects of organic solid cattle manure application on nutritive value of winter cereal forages

Nutritive value of winter cereal forages is one of interested subjects of farmers for animal feeding. Field experiments were established in 2007–2008 and 2008–2009 growing seasons in northeast Turkey to investigate the effect of organic solid cattle manure application (0, 10 and 20 Mg ha^?1 yr^?1) on nutritive value of three annual cereals for forage. The winter cereal forages were: wheat (Triticum aestivum L.), oat (Avena sativa L.) and rye (Secela cereale L.). ADF (acid detergent fiber), NDF (neutral detergent fiber) CP (crude protein), nitrogen, phosphorus, potassium, sulfur, calcium, copper, iron, magnesium, manganese, sodium, zinc and boron (N, P, K, S, Ca, Cu, Fe, Mg, Mn, Na, Zn and B) concentrations were researched in this study. Wheat had the highest CP, N, Ca, Cu, Na and Zn concentration, whereas oat had the lowest ADF and NDF and the highest K, Fe and Mn concentrations. The greatest Mg and P concentrations were determined in rye. Organic solid cattle manure applications had no effect on N and CP contents, but it decreased ADF and NDF contents. However, in most cases it positively affected the P, B, Cu, Fe, Mg and Na concentrations, whereas it decreased K, Ca, Mn and Zn concentrations. The results showed that wheat and oat are more nutritive species than rye in terms of animal feeding and the organic solid cattle manure, in some cases increased the nutritive values of wheat, oat and rye under organic agriculture conditions.     

Isolation of Mycoplasma synoviae from infectious synovitis of chickens

This report describes the first isolations of Mycoplasma synoviae from the synovial sheaths and joints of commercial chickens affected with synovitis in Australia. Over 4 years 3 separate outbreaks were investigated in which up to 20% of birds exhibited clinical signs of poor growth and "hot foot" syndrome (swollen inflamed footpads). Once an outbreak occurred, chronic infection of the farm usually ensued. Grossly the hocks and footpads were swollen by a purulent exudate and associated inflammatory changes with histological features of a severe acute synovitis. Seroconversion of the flocks occurred at the time of the development of lesions. M. synoviae specific antibodies were demonstrated by ELISA in the joint fluid of affected birds. It is concluded that the cases described are similar to avian infectious synovitis syndrome caused by M. synoviae previously described overseas.     

Exogenous applications of salicylic acid affect quality and yield of strawberry grown under antifrost heated greenhouse conditions

Abiotic stress is becoming more prevalent as the intensity of agriculture and the demand for farmable land are ever increasing. Besides drought and salinity stress, chilling or freezing stress is one of the most important limiting factors of crop production all around the world. Salicylic acid (SA) is a common plant‐produced signal molecule that is responsible for inducing resistance to a number of biotic and abiotic stresses. This study was conducted to determine the effect of foliar SA applications on fruit‐quality characteristics and yield of strawberry under antifrost heated greenhouse conditions in two successive experiments. Spraying of 1 mM SA (1 mM) was done once (SA1), twice (SA2), three times (SA3), or four times (SA4) during the vegetation period with 7 d intervals. Concentrations of chlorophyll and minerals were measured in leaves, and vitamin C (ascorbic acid), total soluble solids (TSS), titratable acidity (TA), and color (a*) in fruits. Fruit weight, early yield, and total yield were also determined. Foliar applications of SA positively affected TSS and ascorbic acid (AA) content of strawberry fruits. Salicylic acid treatments had no effect on TA of strawberry fruits. SA4 treatment gave the greatest a* in fruit and chlorophyll‐concentration values in the leaves. It was shown that SA treatments increased the content of all nutrients in the leaves of strawberry plants, and greater values often were obtained from SA3 and SA4 treatments. The early yield and total yield of strawberry were significantly affected by SA applications, among which SA3 and SA4 resulted in the highest early and total yields. The present study suggests that SA3 and SA4 treatments can ameliorate the deleterious effects of low temperatures on strawberry plants and that SA application may offer an economical and simple method for low‐temperature protection.     

Thiamin Requirement of Nile Tilapia,Oreochromis niloticus

Juvenile Nile tilapia, Oreochromis niloticus, were fed to apparent satiation twice daily with purified diets containing 0, 1.0, 2.0, 4.0, 8.0, and 16.0 mg/kg and 0, 2.0, 4.0, 8.0, 16.0, and 32.0 mg/kg of thiamin in separate 14‐ and 8‐wk trials (Experiments 1 and 2, respectively). Fish fed the diet devoid of thiamin developed neurological disorders, anorexia, reduced growth, and feed efficiency and increased mortality (Experiment 2 only) within 4–6 and 8–10 wk for Experiments 2 and 1, respectively. Low red blood cell count (RBC) and hematocrit (Ht) were observed in fish fed the thiamin‐deficient diet. Serum pyruvate was elevated in fish fed the thiamin unsupplemented diet. Serum lactate was not affected by dietary thiamin levels. Whole body protein was unaffected by dietary levels of thiamin. Body moisture and ash increased whereas body lipid decreased in fish fed the thiamin unsupplemented diets. None of these abnormalities were observed in fish fed the thiamin‐supplemented diets. Using the response curves determined by PROC NLMIXED to estimate dietary thiamin levels required for various response variables, a dietary thiamin level of 3.5 mg/kg diet was adequate for optimum growth, feed intake and efficiency, survival, prevention of neurological symptoms, and maintaining normal levels of RBC, Ht, serum pyruvate, and proximate body composition.