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1.
The effects of high temperature stress and supplemental irrigation on seed yield and water use efficiency (WUE) of canola (Brassica napus L.) were studied in a field experiment conducted for 2 years. The experiment was a randomized complete block design arranged in split plot, conducted at Agricultural Research Station of Gonbad, Iran. It was arranged in two conditions, i.e. supplemental irrigation and rainfed. Two cultivars of canola (Hyola401 and RGS003) as subplots were grown at five sowing dates as main plots. The sowing dates were 9 November, 6 December, 5 January, 4 February and 6 March in 2005-2006 and 6 November, 6 December, 5 January, 4 February and 6 March in 2006-2007, to have a wide range of environmental conditions around flowering and seed filling periods, and to coincide reproductive stages of the crop with high temperature stress. Seed yield was improved due to field management practices, such as supplemental irrigation and optimum sowing date. Supplemental irrigation was an efficient practice to mitigate water stress, and to increase aboveground dry matter and seed yield. There was a strongly negative relationship between seed yield and air temperature during reproductive stages. Delay in sowing led to more rapid developmental of canola, decreased aboveground dry matter, leaf area index (LAI), harvest index (HI), WUE, and seed yield. Achieving a high aboveground dry matter was an essential prerequisite for high reproductive growth and a high seed yield. Greater seed yield and WUE at first sowing date were associated with greater LAI and aboveground dry matter, and lower temperatures during reproductive stages. The results support the view that WUE can be used as an indirect selection criterion for seed yield in genotypic selection.  相似文献   
2.
In order to impart barrier properties against water and microorganisms on breathable three dimensional spacer fabrics as medical or technical textiles, fabric samples were treated with two water repellent agents and a quaternary ammonium salt namely cetyltrimethylammonium bromide (CTAB), using pad-dry-cure method. Two different water repellent agents based on hydrocarbon and acrylic copolymer were used. The water repellent property of samples was tested by Bundesmann and contact angle tests. Antimicrobial activity of samples was analyzed quantitatively according to AATCC 100. Simultaneous finishing of samples was done with 3 % CTAB and 4 % fluoroalkyl acrylic copolymer. To study the effect of various treatments on comfort related properties, air and water vapor permeability, water repellency and compression were measured. The results showed that the antimicrobial and water repellent spacer fabrics can be achieved applying selected material without significant changes on their comfort properties. Also a regression model was presented to predict the water vapour permeability of knitted spacer fabrics based on course density (CPC) changing.  相似文献   
3.
Tropical Animal Health and Production - The present study was conducted to estimate autosomal and sex-linked genetic parameters by restricted maximum likelihood method using four different...  相似文献   
4.
ABSTRACT

Background: Traditional field-based methods of measurement of biomass and carbon storage face difficulty in collecting time-consuming and expensive, suggests the use of remote sensing-based techniques. It estimates the economic value of the aboveground biomass (AGB) using satellite remote sensing across the Hyrcanian forests of Iran. Methods: The Landsat-8 OLI sensor data were combined with field-based allometric information of 186 circular sample plots. The AGB was calculated at the plot level using the collected data and specific volumetric mass for species in the studied area. It was followed by calculating the carbon storage using a 50% carbon coefficient and the photosynthesis equation at the forest parcel level. Model results using the random forest and support vector machines. The carbon sequestration value was calculated with USD 25.3 as a shadow value of carbon in 2014 and using the replacement cost approach. Results: The highest performances achieved by RF for biomass, carbon storage and the carbon storage value (Iranian Rials of 0.67% and 16%, respectively). The value was derived once at the plot level of 12.22 million IRR (370.43 USD) per ha. In addition, at the parcel level, which resulted in an estimated value of 12.87 million IRR (390.24 USD) per ha.  相似文献   
5.
The existing standard test method assesses draped fabrics two-dimensionally. In this study, a novel method is introduced to analyze and quantify fabric drapes in 3-D by using shadow moiré method. Six different woven fabrics with dissimilar drape behaviors have been analyzed. A drape index has been mathematically derived from the moiré patterns employing the shadow moiré topography technique. The results have been compared with the standard drape coefficient. The 3-D profile of fabrics has been graphically formed and displayed applying the moiré fringes?? data.  相似文献   
6.
Tropical Animal Health and Production - Separation of autosomal and sex-linked direct additive genetic effects has significant role in sheep breeding programs. Hence, this study was conducted to...  相似文献   
7.
Moisture management behavior is a vital factor in evaluating thermal and physiological comfort of functional textiles. This research work studies functional 3 dimensional (3D) warp knitted spacer fabrics containing high-wicking materials characterized by their profiled cross section. These spacer fabrics can be used for protective vest to absorb a user’s sweat, to reduce the humidity and improve user’s thermal comfort. For this reason, different 3D warp knitted spacer fabrics were produced with functional fiber yarns in the back layer of the fabric (close to the body) and polyester in the front and middle layers (outer surface). Comfort properties such as air and water vapor permeability and wicking and other moisture management properties (MMP) of different fabric samples were measured. It is demonstrated that by using profiled fibers such as Coolmax fiber, moisture management properties of spacer fabrics can be improved, enabling them to be use as a snug-fitting shirt worn under protective vests with improved comfort.  相似文献   
8.
Electrospinning has been recognized as an efficient technique for the fabrication of neural tissue engineering scaffolds. Many approaches have been developed on material optimization, electrospinning techniques, and physical properties of scaffolds to produce a suitable scaffold for tissue engineering aspects. In this study, structural properties of scaffolds were promoted by controlling the speed of fiber collection without any post-processing. PLGA scaffolds, in two significantly different solution concentrations, were fabricated by the electrospinning process to produce scaffolds with the optimum nerve cell growth in a desired direction. The minimum, intermediate and maximum rate of fiber collection (0.4, 2.4, 4.8 m/s) formed Random, Aligned and Drown-aligned fibers, with various porosities and hydrophilicities. The scaffolds were characterized by fiber diameter, porosity, water contact angle and morphology. Human nerve cells were cultured on fiber substrates for seven days to study the effects of different scaffold structures on cell morphology and proliferation, simultaneously. The results of MTT assay, the morphology of cells and scaffold characterization recommend that the best structure to promote cell direction, morphology and proliferation is accessible in an optimized hydrophilicity and porosity of scaffolds, which was obtained at the collector linear speed of 2.4 m/s.  相似文献   
9.
In this paper the feasibility of interlacing current-carrying metallic (conductive) filaments in a rotational permanent magnetic field is investigated. The work contains two parts. Firstly, the effect of magnetic forces on current-carrying metallic filaments in a rotational permanent magnetic field is theoretically studied. In addition, the behavior of a filament under magnetic forces is mechanically analyzed. Secondly, in accordance with the theoretical analysis, a prototype of the proposed system is designed and tested. The experimental results prove the capability of the method to interlace metallic filaments. The proposed method can be employed as a kernel in order to reach a frictionless twister system for other conductive filaments.  相似文献   
10.
Diltiazem (DTZ) is widely used in the prophylaxis of hypertension and treatment of angina. The effects of DTZ and other calcium channel blockers on memory have been discussed with several procedures and different theories have been suggested. In the present study, the effect of DTZ on retention and retrieval of memory in young and aged mice was investigated by using the passive avoidance apparatus. For this purpose, after weighting, coding and classifying the mice, they were grouped as follow: test group received electric shock plus DTZ (10 and 30 mg kg(-1), i.p.), blank group received electric shock plus normal saline and control group received only electric shock. In all three groups delay time of leaving the platform for both retention and retrieval test of memory was measured. DTZ was administered immediately after receiving electric shock in the retention test, but in retrieval test DTZ was administered 24 h after receiving electric shock. The results indicated that 30 mg kg(-1) of DTZ impaired retention and retrieval of young mice memory. The 30 mg kg(-1) of DTZ enhanced retention while 10 and 30 mg kg(-1) of it improved retrieval of aged mice memory.  相似文献   
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