Effects of sowing and harvesting dates on yield and some quality characteristics of crops in sugar beet/cereal rotation system

BACKGROUND: Cereals are the main crops in rotation following sugar beet harvest. However, a delay in planting winter cereals as a result of late sugar beet harvest is a disadvantage in sugar beet/cereal rotations. In this study, field trials were carried out to investigate the effects of sowing and harvesting dates on the yield and quality of sugar beet (Beta vulgaris L.) and cereals (wheat, Triticum aestivum L., and six‐rowed barley, Hordeum vulgare L.) during two consecutive years. Beet was sown on three dates and harvested on four dates, followed by cereals which were sown on four dates. Root yield and digestion ratio (sugar beet) and grain yield, 1000‐kernel weight, test weight and protein content (wheat and barley) were determined. RESULTS: The highest root yield (52.53 t ha^?1) was obtained from early sown (5 April) and late harvested (1 November) beet, while the highest digestion ratio (17.4%) was obtained from late sown (3 May) and late harvested (1 November) beet. Lower cereal grain yields were obtained from later sowings. The highest grain yields (5.87 and 6.02 t ha^?1) were obtained from earlier sown wheat. Protein content was also affected by sowing date, which appeared to be very important under unstable climatic conditions. CONCLUSION: It is essential to consider the timing of sowing of cereal crops when unstable climatic conditions are present. Hence sowing date recommendations in regular climatic conditions may be misleading for countries dependent on winter rainfall for cereal production. Copyright © 2007 Society of Chemical Industry     

Effects of sulphurisation on vitamins (A,C and E) and malondialdehyde in apricots

In this study, the 1.0 m H₂SO₄ solution was used as a sulphur source to sulphurise apricots. Apricot samples were immersed into 1.0 m H₂SO₄ solution at room temperature for time of 30, 60 , 120, 180 and 240 min. Amounts of vitamins (A, C and E) and malondialdehyde (MDA) were determined as function of sulphurisation time and thus, sulphur content. It was determined that the optimum immersion time for sufficient sulphur content is 120 min. It is concluded that while amounts of vitamins decrease, the level of MDA increases with increasing immersion time and thus, sulphur contents.     

Geometric design of slider-crank mechanisms for desirable slider positions and velocities

In problems requiring uniform cutting speeds uniform flow rates etc. slider-crank mechanisms provide economical solutions. Thus, the problem of designing slider-crank mechanisms for desirable slider positions and velocities is handled within a geometric framework in this paper. Here, the rotation of the crank has been related to the translation of the slider through a linear function. A unified methodology comprising the so-called Subdomain, Galerkin methods together with the classical collocation method is implemented to find the values of the parameters involved. The effectiveness of the methodology has been demonstrated on numerical examples. Since more than one solution results from the solution process, it is always possible to form multi-loop mechanisms. Moreover, designs with low velocity errors in the forward stroke exhibit similar feature in the backward stroke too.     

Prevention of the development of polluting characteristics in cooking water residue from nixtamalisation of corn by removing solid lime particles

Removing solid lime particles (SLP) may help to prevent polluting characteristics of corn cooking wastewater (nejayote). The objective of this study was to evaluate the polluting characteristics of nejayote and characteristics of nixtamal, masa and tortilla using SLP-free solutions (SLPF) for the nixtamalisation process. Two SLPF treatments: calcium hydroxide (CHYDROX) and calcium oxide (COXIDE) were compared against traditional nixtamalisation (TRADNIX). Polluting characteristics including pH, settleable solids, total hardness, alkalinity and chemical oxygen demand (COD) reduced by 29.5% and 24.3%, 61.9% and 63.3%, 46.3% and 54.7%, 43.3% and 55.1%, 41.1% and 67.7% in CHYDROX and COXIDE, respectively, compared to TRADNIX. Masas and tortillas from SLPF treatments were whiter than those from TRADNIX. Moisture in SLPF tortillas was lower by 4.3–6.3% compared to TRADNIX. Tortillas from SLPF treatments had higher maximum tensile strength (0.04–0.08 N mm⁻²) than TRADNIX. Removing SLP is a viable strategy for preventing pollution from the nixtamalisation process.     

Point-Value WENO Multiresolution Applications to Stable Image Compression

The ideas that lead from ENO to Weighted ENO (WENO) reconstructions (i.e. cell-average “interpolators”), devised and extensively used for the design of highly accurate shock capturing schemes for conservation laws, are applied in this paper to obtain weighted essentially non-oscillatory point-value nonlinear interpolators that can generically achieve an order of accuracy of 2r, when using stencils of 2r points at regions where the interpolated function is smooth. This interpolatory technique can be used in Harten’s multiresolution framework for image compression applications.     

Associations between subclinical hypocalcemia and postparturient diseases in dairy cows

Dairy cows suffer blood Ca losses as lactation begins and might be affected by hypocalcemia in its clinical (total serum Ca concentration <1.50 mM) or subclinical form (total serum Ca concentration ≤2.14 mM). Several studies have suggested that hypocalcemia is associated with different health problems of the cow but results from different studies are not consistent. The objective of this study was to assess potential associations between subclinical hypocalcemia (SCHC) and displaced abomasum, intramammary infections, metritis, retained placenta, and ketosis. Also, the associations between SCHC and milk yield and reproductive function were evaluated. After discarding cows (32) with clinical hypocalcemia, a total of 764 cows from 6 different commercial farms were enrolled in this study. Blood samples were collected at 24 to 48 h postcalving and analyzed for total Ca concentration. Odds ratios of the different afflictions potentially associated with SCHC were calculated. Seventy-eight percent of the analyzed cows incurred SCHC. The occurrence of displaced abomasum, ketosis, retained placenta, and metritis was 3.7, 5.5, 3.4, and 4.3 times more likely, respectively, in cows that had SCHC than in cows with normocalcemia. Furthermore, the risk of incurring retained placenta or metritis increased in multiparous cows as serum Ca concentrations decreased compared with that in primiparous cows. Normocalcemic cows, independent of parity, were more likely to show their first estrus sooner after calving than SCHC cows, but no correlation was found between SCHC and other reproductive parameters. Different serum Ca concentration cutoffs were identified for several postpartum afflictions (≤1.93, ≤2.05, ≤2.05, and ≤2.10 mM for ketosis, retained placenta, metritis, and displaced abomasum, respectively). In conclusion, SCHC, defined as serum Ca ≤2.14 mM, is a frequent illness affecting the majority of the dairy cows with important repercussions on health. However, if SCHC were to be used to predict postpartum disease, different serum Ca cutoff points are likely to be needed because best predictive cutoff values varied among postpartum ketosis, displaced abomasum, retained placenta, and metritis.