A Structural Perspective on the RNA Editing of Plant Respiratory Complexes

The last steps of respiration, a core energy-harvesting process, are carried out by a chain of multi-subunit complexes in the inner mitochondrial membrane. Several essential subunits of the respiratory complexes are RNA-edited in plants, frequently leading to changes in the encoded amino acids. While the impact of RNA editing is clear at the sequence and phenotypic levels, the underlying biochemical explanations for these effects have remained obscure. Here, we used the structures of plant respiratory complex I, complex III2 and complex IV to analyze the impact of the amino acid changes of RNA editing in terms of their location and biochemical features. Through specific examples, we demonstrate how the structural information can explain the phenotypes of RNA-editing mutants. This work shows how the structural perspective can bridge the gap between sequence and phenotype and provides a framework for the continued analysis of RNA-editing mutants in plant mitochondria and, by extension, in chloroplasts.

Timber Losses during Harvesting in Managed Shorea robusta Forests of Nepal

Logging and sawing of timber using conventional tools by unskilled workers causes enormous damage to the valuable timber, residual stand, regeneration, and forest soil in Nepal. The purpose of this study was to find out the volume reduction factor and identify major strategies to reduce timber losses in the tree harvesting process in the Terai Shorea robusta forest of Nepal. Field measurements and product flow analysis of 51 felled trees from felling coupes and randomly selected 167 sawed logs were examined to study harvesting losses. Responses from 116 forest experts were analyzed to explore strategies for reducing harvesting and processing losses. The results showed that timber losses in the felling and bucking stage with and without stem rot were 23% and 22%, respectively. Similarly, timber losses in the sawing stage with and without stem rot were 31% and 30%, respectively. Paired t-test at 5% level of significance revealed that there was significant loss in both tree felling and log sawing stages with present harvesting practice. The most leading factor contributing to timber loss in all of the three stages was the use of inappropriate equipment during tree harvesting. Use of synthetic ropes for directional felling and skidding as well as flexible and portable sawing machine with size adjustment options during sawing were mainly recommended as strategies to reduce timber losses. This study serves as a baseline study to identify and quantify timber losses in different stages of tree conversion and also formulate their reduction strategies in Nepal.

Harvesting of Chlorella sorokiniana BR001 cultivated in a low-nitrogen medium using different techniques

ABSTRACT: The harvesting process is a current challenge for the commercial production of microalgae because the biomass is diluted in the culture medium. Several methods have been proposed to harvest microalgae cells, but there is not a consensus about the optimum method for such application. Herein, the methods based on sedimentation, flocculation, and centrifugation were evaluated on the recovery of Chlorella sorokiniana BR001 cultivated in a low-nitrogen medium. C. sorokiniana BR001 was cultivated using a low-nitrogen medium to trigger the accumulation of neutral lipids and neutral carbohydrates. The biomass of C. sorokiniana BR001 cultivated in a low-nitrogen medium showed a total lipid content of 1.9 times higher (23.8 ± 4.5%) when compared to the biomass produced in a high-nitrogen medium (12.3 ± 1.2%). In addition, the biomass of the BR001 strain cultivated in a low-nitrogen medium showed a high content of neutral carbohydrates (52.1 ± 1.5%). The natural sedimentation-based process was evaluated using a sedimentation column, and it was concluded that C. sorokiniana BR001 is a non-flocculent strain. Therefore, it was evaluated the effect of different concentrations of ferric sulfate (0.005 to 1 g L-1) or aluminum sulfate (0.025 to 0.83 g L-1) on the flocculation process of C. sorokiniana BR001, but high doses of flocculant agents were required for an efficient harvest of biomass. It was evaluated the centrifugation at low speed (300 to 3,000 g) as well, and it was possible to conclude that this process was the most adequate to harvest the non-flocculent strain C. sorokiniana BR001.

Analysis of Energy Harvesting Enhancement in Piezoelectric Unimorph Cantilevers

Environmental energy harvesting is a major operation in research and industries. Currently, researchers have started analyzing small-scale energy scavengers for the supply of energy in low-power electrical appliances. One area of interest is the use of piezoelectric materials, especially in the presence of mechanical vibrations. This study analyzed a unimorph cantilever beam in different modes by evaluating the effects of various parameters, such as geometry, piezoelectric material, lengths of layers, and the proof mass to the energy harvesting process. The finite element method was employed for analysis. The proposed model was designed and simulated in COMSOL Multiphysics, and the output parameters, i.e., natural frequencies and the output voltage, were then evaluated. The results suggested a considerable effect of geometrical and physical parameters on the energy harvesters and could lead to designing devices with a higher functional efficiency.

MYCOFLORA AND AFLATOXIN LEVELS IN WALNUT SAMPLES STORED IN DIFFERENT PACKAGING MATERIALS IN OGUN STATE

Aflatoxin levels in nuts and fruits pose a great threat to food storage and availability. This study aimed at determining the mycoflora and aflatoxin level in stored walnut under various conditions. Freshly harvested walnuts were stored for 90 days in three different media: jute bags, Plastic containers and sterile polythene bags under room (37ᵒC) and refrigeration (4ᵒC) temperature. After 90 days of storage, the stored walnuts were examined for fungal growth at one month interval after which colonial and morphological characterization were carried out to identify the fungi present. Proximate analysis and aflatoxin content of the walnut samples were determined by standard methods. Fungi isolated from the walnuts include; Aspergillus niger, Saccharomyces cerevisae, Penicillum notatum, Aspergillus sydowi, Fusarium oxysporium, and Rhizopus stolonifer. Walnuts stored in plastic container at room temperature had the lowest aflatoxin level of 0.002 ng/kg while that stored in polythene bags had the highest (0.054 ng/kg). Proximate analysis also revealed that walnuts stored in polythene bag reduced significantly (p<0.05) in protein, ash content, fat, fibre, moisture and carbohydrates while samples stored in jute bag and plastic container remained unchanged. This study shows that storage methods contributed to the overall quality, shelf life and aflatoxin content of walnut and hence care should be taken during post harvesting process.

The reasons for the loss of wheat from the harvest grown in the fields of Russia

A comparative analysis has been performed of statistical data on wheat losses in the fields from 2001 to 2019, using Russia as an example, which enables us to estimate the wheat losses from the crop grown accurately when harvested using combined harvesters. The analysis of the wheat losses from the grown crop in the fields was carried out in three directions based on the total sown areas, the average wheat yield, and the total harvested areas of the winter and spring wheat; according to the official data of the “Expert and Analytical Center for Agribusiness” and “Statistical Collections of Agriculture in Russia.” Analysis of wheat losses in the Russian Federation fields has been compared with the first and second directions. This analysis helps to identify the causes that affect the loss of wheat during the harvesting process by combined harvesters.

A Dwarf French Bean - Anisia

Phaseolus vulgaris is one of the most important vegetables with high nutritional value consisting in proteins, iron, magnesium, folic acid and complex carbohydrates. The aim of this study was to obtained a dwarf french bean genotype with the following characteristics: yield and quality potential, earliness and extreme environmental conditions. The variety was obtained by repeated individual selection and now is submitted to the conservative selection program. For all agro-morphological characters, descriptive statistics were calculated. The pods of Anisia beans are yellow and have a simultaneous maturation, easing the harvesting process. The average weight of a pod at consumption maturity was 4.23 g. The yield potential of fresh pods varies between 18-20 t/ha. From our studies, Anisia cultivar is suitable for cultivation both organically and conventionally. The research has been completed with obtaining of a new variety of dwarf french bean that has been registered in the Official Catalogue of Romanian Crop Plants under the name ‘Anisia’. The variety has a distinct phenotypic expressiveness with a high yield and quality potential.

Dissemination of corn sheller machines to increase productivity and efficiency for corn farmer associations in Wonogiri Regency

Corn is a superior agricultural product for the Giri Harjo I farmer group, Girikikis Village, Giriwoyo District, Wonogiri. However, farmers process and peel corn manually, so it takes a more time and inefficient. In order to overcome this problem, this community service designed and made a corn sheller machine that was used to simplify and increase the productivity in the corn harvesting process. This service activity begins with the delivery of the corn sheller machine to the farmer group, then exposure and training on the use of the machine. Corn shelling is accomplished by inserting the corn into the sheller shaft, after which the grinding knife separates the corn kernels from the cob. The shelling test results show that this machine works well, is practical to use, is highly portable, the production process is faster, the corncobs are not damaged, and the electric power consumption is low. This machine has a 0.5 HP motor and a production capacity of 183 kg/hour for shelling corn kernels.

ACAN SPEED, ATTACK ANGLE AND CUTTING FORCE, AFFECT THE QUALITY OF SUGARCANE HARVEST?

The base cut of cultures is one of the most studied parameters, and the variables involved in this process should be better evaluated under controlled conditions. The aim of this study was to evaluate, using an electromechanical device, under controlled conditions, the influence of the cutting angle and the machine's translation speed on the impact force generated on sugarcane stalks in mechanized harvesting. The study was carried out at the Nempa - Center for Testing of Agroforestry Machines and Tires (NEMPA) at UNESP/Botucatu. For the tests, the Sugarcane Basal Cut Testing Device (BCTD) was used. The collected data were evaluated using multiple linear regression analysis, using the stepwise method. The results showed that the angulation of the cutting blades is the most significant variable in relation to the impact force generated in the cutting process of sugarcane stalks, this research also managed to assess that the intensity of the angulation effect is more than 2 times greater than the effect generated by the displacement speed in the mechanized harvesting process.

Design and Experimental Study of Potato-Soil SeparationDevice for Sticky Soils Condition

The potato-soil separation device comprising five function areas (i.e., shearing, bending, throwing, cleaning, and conveying) was developed to address the mentioned problems (e.g., soil with high moisture content, large viscosity, and poor separation efficacy) in the harvesting process for winter idle paddy fields of Southern China. Given the kinetic analyses for the potato-soil mixture of five function areas, the crucial factors of the effect of potato-soil separation were determined. Subsequently, the orthogonal test of 4 factors and 3 levels was performed, and the percentage of small soil λ, the percentage of soil adhering to potato tuber γ, and damage rate of potato tuber K were adopted as assessment indexes. Regression analyses and programming for the orthogonal test result were conducted to optimize the device run parameters, and the optimal run parameters included the rotational speed of the soil-crushing mechanism of 84.18 r/min, linear velocity of second-stage lifting chain of 0.75 m/s, and inclination angle of lifting chain of 15.87°. The field experiments were performed with the modified potato harvester. As indicated from the result, the visible potato rate was 94.31% and damage rate of potato was 0.89%, and the requirement of the national standard was satisfied. This study presented technical feasibility data and equipment for potato-soil separation under sticky soils condition.