Development and evaluation of a dual-purpose machine for chopping and crushing forage crops.

Reducing reliance on fossil fuels with clean and sustainable alternatives is essential for mitigating climate change and global warming-related environmental concerns. Previous researchers have studied the performance of choppers and crushers as separate units powered by diesel or gasoline engines. Nowadays, an increasing interest in producing Eco-friendly machines that stand out for being dual purposes, cost-effectiveness, and with lengths suitable for feeding ruminants are imperative to achieving economic and sustainable goals. Therefore, this study aims to solve these issues and gaps by developing and evaluating a dual-purpose forage machine for chopping and crushing operations to achieve both operations more efficiently and at a lower cost. The developed forage machine's performance was evaluated for chopping operation using maize stalks with four different rotational speeds of 1200, 1400, 1600, and 1800 rpm and four different moisture contents of 22.7, 43.3, 59.8, and 74.6% (w.b.). Also, the crushing operation was evaluated using maize ears with four different crusher speeds of 1200, 1400, 1600, and 1800 rpm and three different sieves with holes' diameters of 6, 8, and 10 mm. The results concluded that the highest efficiencies with values of 94.17 and 92.85% were obtained at 1800 rpm chopper rotational speed and 22.7% moisture content for the chopper and 1200 rpm crusher rotational speed and 10 mm sieve hole diameter for the crusher, respectively. At these proper operational parameters, the machine productivity of 2.44 and 0.31 ton.hr-1, the specific energy requirements of 3.22 and 4.50 kW h.ton-1, and the estimated production costs of 23.56 and 121.24 EGP.ton-1 (1.25 and 6.38 USD.ton-1) were obtained for chopper and crusher, respectively.

Analysis of the correlation between mesocarp biomechanics and its cell turgor pressure: A combined FEM-DEM investigation for irrigation-caused tomato cracking.

Fruit mesocarp cracking caused by improper irrigation during development manifests at the macroscale but is ultimately the result of increasing cell turgor pressure at the microscale. Hence, a cell finite element (FE) model including shape, protoplast turgor pressure, and ripening information and a mesocarp tissue block discrete element (DE) model including the features of cell shape and number, were developed to predict the biomechanical correlation between mesocarp and its cell. The validated cell FE model with an internal turgor pressure of 12.9 kPa could reproduce the experimental force-deformation behavior of a single cell in compression up to 11% deformation with an average relative error of 5.8%. The validated mesocarp tissue block DE model could reproduce the experimental force-deformation behavior of a mesocarp block in compression up to 20% deformation with an average relative error of 9.5%. Sensitivity and regression analysis showed that turgor pressure was the most important factor affecting cell biomechanics, followed by cell shape and wall elastic modulus. Similarly, the apparent elastic modulus of the cells has the most significant effect on the mesocarp tissue biomechanics, followed by the number and shape of cells. Finally, a mathematical model was obtained to quantitatively describe the relationship between the elastic modulus of the mesocarp and its cell turgor pressure. This study contributes to a better understanding of the biomechanical mechanisms of irrigation-caused tomato fruit cracking at the cellular level and the development of strategies to prevent fruit cracking through a combination of gene breeding and irrigation management.

A combined machine for collecting and chopping rice straw.

Due to the recent high prices of livestock feed in the world and the new sustainable management practices of rice straw, livestock farmers are obligated to either use or purchase rice straw and cut it to desired lengths to feed ruminants. Therefore, this study aimed to construct a combined machine for collecting and chopping rice straw for lengths preferred in feeding ruminants. The combined machine comprises three main units: a picking up unit, a chopping unit, and a takeout unit. Field experiments were performed on average rice straw moisture content of 25% (w.b.) to evaluate the performance of the combined machine, under factors of 1.3, 1.6, 1.9, and 2.2 km h-1 forward speeds, elevator velocities of 0.79, 0.94, and 1.10 m s-1, and chopping knives rotational speeds of 1600, 2000 and 2400 rpm. The obtained results indicated that the consumed specific energy was 90.94 kWh ha-1 to achieve the highest field capacity of 0.24 ha h-1, with collecting efficiency of 95.30% at a forward speed of 2.2 km h-1, elevator velocity of 1.10 m s-1 and rotational speed of 2400 rpm for chopping knives. In order to achieve the highest chopping quality of 95%, it is recommended to operate the elevator velocity at 0.79 m s-1, rotate chopping knives at 2400 rpm, and drive the tractor at a forward speed of 1.3 km h-1. The total operating cost of the combined machine is lower than the traditional methods by about 49.84%.

A 12-week, randomized, double-blind, placebo-controlled, sequential parallel comparison trial of ziprasidone as monotherapy for major depressive disorder.

OBJECTIVE: To study ziprasidone monotherapy for major depressive disorder, defined according to the DSM-IV. METHOD: One hundred twenty outpatients were enrolled between June 2008 and September 2010 in a 12-week study that was divided into two 6-week periods according to the sequential parallel comparison design. Patients were randomized in a 2:3:3 fashion to receive ziprasidone for 12 weeks, placebo for 6 weeks followed by ziprasidone for 6 weeks, or placebo for 12 weeks. The main outcome measure was the 17-item Hamilton Depression Rating Scale (HDRS-17), with the Quick Inventory of Depressive Symptomatology, Self-Rated (QIDS-SR), and Clinical Global Impressions-Severity of Illness scale (CGI-S) serving as the study secondary measures. RESULTS: One hundred twenty patients (53 women [44.1%]) were randomized to treatment. The mean (SD) age of these patients was 43.7 (11.0) years. Mean (SD) baseline HDRS-17, CGI-S, and QIDS-SR scores were 19.9 (5.0), 4.3 (0.6), and 15.6 (3.0), respectively. There was no statistically significant difference in reduction of depressive symptoms, response rates, or remission rates between ziprasidone- or placebo-treated patients. This was true for both the study primary as well as secondary outcome scales. CONCLUSIONS: In conclusion, treatment with ziprasidone monotherapy was not associated with any statistically significant advantage in efficacy over placebo. Although studies involving larger sample size would be required to have adequate statistical power to detect treatment differences smaller than 2.5 points on the HDRS-17, such differences would be of questionable clinical relevance. TRIAL REGISTRATION: ClinicalTrials.gov identifier: NCT00555997.