Digestive proteases of Papilio demoleus : Compartmentalization and characterization

Digestive proteolytic activities were studied in the larval midgut of Papilio demoleus by using azocasein, specific substrates and inhibitors regarding enzymatic allocation in the alimentary canal. The highest proteolytic activity was found in the midgut rather than foregut and hindgut that highest proteolytic activity was observed in soluble fraction. All specific proteases were almost equally distributed in both the anterior and posterior midgut except for trypsin- and chymotrypsin-like proteases, which showed the highest activity in the anterior midgut. Two peaks were observed in alkaline and acidic pHs when general proteolytic activities were assayed using azocasein in soluble and membrane-bound fractions. Specific substrates revealed the presence of trypsin-like, chymotrypsin-like, elastase, cathepsins B and L as well as two exopeptidases. These findings were confirmed using specific inhibitors including PMSF, TLCK, TPCK, SBTI, cystatin, DTT, E-64, EDTA and phenanthroline. Determination and characterization of the insect’s digestive proteases will enable development of pest control by designing protease inhibitors. This procedure will help us to designate an efficient pest control method with the lowest impact on the environment.     

Spatial variation of infiltration rate and compactness in paddy fields

Percolation loss of water in rice fields is a major cause of low water use efficiency. Variation of infiltration rate and soil compactness in four paddy fields (with clay, silty clay, clay loam, and loam textures) was investigated in northern Iran. In each field, in longitudinal and transverse directions, points located 0.5, 2.5, 6.5, 12.5, … m from the bunds were selected and water infiltration rate and resistance to penetration of a pocket penetrometer were measured. The results showed that in clay soil, average final infiltration rate (f _c) in longitudinal direction, transverse direction, and center of the field was 0.216, 0.136, and 0.08 cm day⁻¹, respectively. The f _c for loamy soil was 2.77, 2.32, and 0.409 cm day⁻¹, respectively. Similar differences were observed in the other two soil textures. In general, effect of direction of the field for measuring infiltration rate was not statistically significant. Loam and clay loam soils, with resistance to penetration of 0.37 and 0.33 kg cm⁻², were not significantly different. But, clay and silty clay soils with resistance to penetration of 0.25 and 0.14 kg cm⁻² were significantly different (P < 0.05). Resistance to penetration of the penetrometer was not affected significantly (P < 0.05) by direction of measuring this parameter in the field. The conclusion is that if measured soil physical properties in a paddy field are going to be representative of the whole field, they should be measured at different locations, especially near the bunds. Another strategy for obtaining a representative infiltration rate or compactness for a paddy field is uniform puddling of the field.     

Stress Response of Juvenile Beluga,Huso huso,to Light and Tank Colors

Effects of light and tank colors on stress response of juvenile beluga sturgeon, Huso huso, was investigated by the measurement of some sero-haematological parameters and carcass chemical analysis. The analysis was based on the responses of 64 specimens (initial weight 98.83 ± 1.42 g) reared under white, red, green, or blue light, and 48 specimens reared in white, black, or blue tanks, all for 12 weeks. Blue/green light and black tanks produced positive effects on cortisol that can be related to physiological condition and stress.     

α-Farnesene and antioxidative enzyme systems in Asian pear (Pyrus serotina Rehd.) fruit

The effects of 1-methylcyclopropene (1-MCP) on ripening, superficial scald and concentrations of α-farnesene, conjugated trienols (CTols) and antioxidant enzyme activity of ‘KS₆’ Asian pear (Pyrus serotina Rehd.) were studied. 1-MCP treated (2 μL L^?1) or untreated control fruit were stored at 1 °C and 90–95% RH for up to 120 days. 1-MCP treated fruit were firmer than untreated fruit. Application of 1-MCP delayed skin color change. Scald appeared after shorter storage duration and was reduced, but not entirely controlled, with 1-MCP. Accumulation of α-farnesene and oxidation were slower in skin of 1-MCP treated fruit compared with controls. Catalase and peroxidase activities in untreated fruit either increased while activities decreased in 1-MCP treated fruit. Superoxide dismutase activity remained stable. The treatment of Asian pears with 1-MCP followed by cold storage maintained textural characteristics with less scald incidence.     

Statistical optimization of wool dyeing with Alizarin Red S as a natural dye via central composite design

Recently a revival interest in the use of natural dyes in textile coloration has been growing. The major parts of natural dyes are anthraquinones. Depending on substituents, anthraquinone compounds are dyes, as represented by Alizarin Red S (ARS) which is a major constituent of the natural colorant madder. In this study, colorization of wool fiber by ARS as a natural dye was studied. The progress of the colorization process was followed spectrophotometrically at 500 nm as λ _max. The effective factors on the process were investigated using one factor at a time (OFT) method. Then, the central composite design (CCD) method was applied to design experiments for the evaluation of the interactive effects of the four most important operating variables. The values of the optimized factors for OFT and CCD methods in wool dyeing with ARS were respectively as follow: temperature 70 °C and 55 °C, L/R: 40/1 and 40/2, pH 5.0 and 2.5 and time 60.0 min and 42.0 min. The predicted results by CCD had significantly higher exhaustion percentages and relatively better fastness properties than OFT and were found to be in a good agreement (R²=0.9908) with those obtained by performing experiments. Finally, the obtained results were shown a good wash fastness for dyed wool with ARS.     

Correction to: Improved model for studying hydrological process in the field-to-field irrigation system

Paddy and Water Environment -     

Effect of puddling intensity on physical properties of a silty clay soil under laboratory and field conditions

Conventional tillage and planting method for rice (Oryza sativa L.) production in northern Iran is wet tillage (puddling). Effect of different puddling intensities on physical properties of a silty clay soil (Typic Haplodalfs) was investigated under laboratory and field conditions. Changes in soil physical parameters and water requirement for puddling were measured. For laboratory experiments, undisturbed cylindrical soil samples (diameter and height of 50 cm), were used. A laboratory puddling apparatus was designed and constructed. The puddling intensity was measured by duration of puddling. Four levels of puddling intensity were used as: P ₀ (no puddling, control), P ₁ (low), P ₂ (medium) and P ₃ (high). For field tests, 12 plots of 8 × 4 m were selected. The first tillage was performed with a moldboard plow and then the plots were puddled with different intensity using a rotary tiller. The results showed that under laboratory conditions, water content of the puddled layers decreased with an increase in settling time. During drying period, P ₀ dried faster than P ₁, P ₂ and P ₃. Puddling with low intensity in laboratory and field conditions caused bulk density of 0–15 cm soil layer to decrease by 24.07 and 25.45%, respectively. Increasing puddling intensity increased the bulk density. Bulk density increased with time as particles settled after halting the puddling. Bulk density increased with depth as well. Under laboratory conditions, increasing puddling intensity from P ₁ to P ₂ reduced percolation rate significantly. For all puddling intensities, soil moisture characteristic curves of both field and laboratory samples showed that puddling increased the amount of water retained over the whole range of suctions. More water was needed for P ₃ as compared to P ₁ and P ₂. Under the laboratory and field conditions, the P ₃ required 27.72 and 28.58% more water as compared to P ₂, respectively. Although the mechanisms implemented for puddling were different under laboratory and field experiments, the results were similar. Bulk density, soil moisture content and water percolation rate decreased faster in the puddled soil under field and laboratory conditions. Therefore, to reduce the cost and time, the laboratory method could be used to study the effects of puddling intensity on physical properties of paddy soils. Medium intensity puddling was shown to be the proper tillage practice for paddy fields with silty clay soil.     

Lamb survival analysis from birth to weaning in Iranian Kermani sheep

Survival records from 1,763 Kermani lambs born between 1996 and 2004 from 294 ewes and 81 rams were used to determine genetic and non-genetic factors affecting lamb survival. Traits included were lamb survival across five periods from birth to 7, 14, 56, 70, and 90 days of age. Traits were analyzed under Weibull proportional hazard sire models. Several binary analyses were also conducted using animal models. Statistical models included the fixed class effects of sex of lamb, month and year of birth, a covariate effect of birth weight, and random genetic effects of both sire (in survival analyses) and animal (in binary analyses). The average survival to 90 days of age was 94.8%. Hazard rates ranged from 1.00 (birth to 90 days of age) to 1.73 (birth to 7 days of age) between the two sexes indicating that male lambs were at higher risk of mortality than females (P < 0.01). This study also revealed a curvilinear relationship between lamb survival and lamb birth weight, suggesting that viability and birth weight could be considered simultaneously in the selection programs to obtain optimal birth weight in Kermani lambs. Estimates of heritabilities from survival analyses were medium and ranged from 0.23 to 0.29. In addition, heritability estimates obtained from binary analyses were low and varied from 0.04 to 0.09. The results of this study suggest that progress in survival traits could be possible through managerial strategies and genetic selection.     

Evaluation of the potential effects of abortion on the productive performance of Iranian Holstein dairy cows

Calving records from the Animal Breeding Center of Iran collected from January 1983 to December 2007 and comprising 1 163 594 Holstein calving events from 2552 herds were used to evaluate the potential effect of abortion occurrence on 305‐day milk yield, milk fat yield, fat percentage of milk and milk protein yield in Iranian Holsteins. Statistical analyses of production traits were performed using a linear mixed model procedure. Normal‐calved cows had greater 305‐day milk production, fat yield and protein yield of milk than abortive‐calved cows (P < 0.05). However, abortive‐calved cows had the greater milk fat percentage than normal calved cows (P < 0.05). The linear and quadratic effects of age of dam were significant on all of the studied traits (P < 0.05). The results of regression analysis showed that increase in the quadratic effect of age can cause an increase in the fat percentage of milk for all calvings including normal and abortive calvings. Because abortion is one of the most important conditions that limit a cow's ability to produce, maintaining the general health of cattle is important in minimizing the risk of abortion problems.