Design and Optimization of the Vertical Plate Metering Device for Alfalfa Seeds Precision Based on Engineering Discrete Element Method (EDEM)

The research is financed by China Agriculture Research System (CARS34) Abstract The vertical plate seed metering device enhancement and constraints mass flow rate when added to the device improve mass flow performance of alfalfa vertical plate device. Alfalfa forage crop is a potential feeding nutrient and the backbone of dairy production success in China. Engineering discrete element method EDEM was adopted for simulation computing and analysis of the seed-filling performance of the vertical plate metering device with three cell shapes under desired rotational speeds. The results showed significant differences at P< 0.05 of seed filing performance in relation to the rotational speed and cell shapes. Triangular cell shape had indicated the lower mass flow at 8x10-5 kg/s compared to the V-shape of 12x10-4 kg/s and U-shape of 8x10-3 kg/s, 20 to 30% reduction, respectively. The rotational velocity of the vertical plate exceeded 30rpm the cell units reach the optimum seed filling efficiency resulted in 30% decrease of the mass flow rate, the results indicated more seeds disturbance, reduces seed filling by enhancing seeds accessibility and falling, from cells. Furthermore, the T-shape had a lower seed filling and higher seeds releasing in comparison to the V-shape and U-shape cells. The lower seed filling found to be the higher filling efficiency while the higher seed filling leads to the lower filling efficiency. Keywords: Alfalfa seed model, cell, filling performance, mass flow, simulation EDE

Effects of Moisture Content on Selected Physical and Mechanical Properties of Alfalfa Seeds

Alfalfa is one of the most widely planted forage legume in the world and that because of its tolerance, adaptation, high yield and nutritious value. Physico-mechanical properties of alfalfa seed are very crucial in the machine designing and processing operations. In this study, some of the physical and mechanical properties of alfalfa seed cultivar were investigated under laboratory condition, as desired for the design of a metering device.  Seven moisture contents were introduced to the initial content of 7.98%, d.b. The geometric and gravimetric characteristics were determined. Correlation equation models were developed based on the function of moisture contents. The means average parameter values of the length, width, thickness, aspect ratio, seed mass, arithmetic, geometric mean diameter, true and bulk density, porosity seed volume, and surface area ranged between 2.356 to 2.718mm, 1.390 to 1.473mm, 1.071 to 1.345mm, 0.68 to 0.776%, 1.7968 to 2.295g, 1.466 to 1.589mm, 1.141 to 1.517mm and 1.466 to 1.589g/cm31.199 to 0.830g/cm3, 0.10 to 0.44%, 0.7383 to 0.79426, and 6.305 to 7.2438mm2, respectively. While, the plywood surface had the highest value of the coefficient of friction as the roughest, followed by polished steel and rubber, glass the least surface roughness. However, the germination rate (%) increased as seed damages decreased, as the coefficient of internal friction decreases from 0.127 to 0.095, while the cohesion increasing from 2.11 to 5.95. The angle of repose resulted in a non-linear increase from 27.05o to 28.68o, 28.86o to 29.86o, 31.49o to 32.35o, and 32.47o to 33.21o as moisture content increased from7.98 to 22.12% d.b. Keywords: alfalfa seed, moisture content, mechanical property, physical propert

Panel Data Analysis of African’s Trade: The Gravity Model Approach

The theoretical justification of the gravity model in the analysis of bilateral trade was applied in the generalized gravity model to analyze the African’s trade with China and its major trading partners using the panel data estimation technique. Estimate of the gravity model of trade (sum of exports and imports), the export and import gravity model. Data for the period 1980-2015. The empirical results show that African’s trade is positively determined by the size of the economies, GDP, per capita GDP, FDI, a differential of the countries involved and openness of the trading countries. The major impacts of African’s exports are the exchange rate, partner countries’ total import demand and openness of the Africa economy. All three factors affect the African’s exports were found positive. The exchange rate, on the other hand, indicated no effect on the African’s import; rather than the imports were affected by inflation rates, per capita income differentials and openness of the countries involved in the trade. Transportation cost is found a significant factor in influencing African’s trade negatively. Also, Africans imports are found to be influenced to a great extent by the distance between China and African. The country-specific effects show that African would do better by trading more with its neighboring countries. The indication of trade sector effects matter and that potential product vary considerably in their sensitivity to distance and country factors which have prominent revealed comparative advantage. African should diversify its exports and improve its trade diplomacy. Keywords:  Panel data, gravity model. potentials, export, China, and Africa

The Marginal Profitability Share among of Stakeholders in Rice Value Chain: A Case Study in Banian Commune, Faranah Prefecture, Guinea

Africa’s inability to achieve rice self-sufficiency is the result of major constraints in the entire chain of the rice production industry. The study aims to carry out the participatory diagnosis analysis for rice income sector in order to stimulate the yield improvement to stabilize food security. The study was carried out in rural commune of Banian through eleven villages. Data were collected through intensive survey of randomly selected 343 respondents using gross margin analysis and descriptive analysis whiting participatory method. The diagnosis included the producers and rice processors (buyer-steamers and shellers). Assessing these three producer categories, it was indicated that the net income of rice farmers is 140, 313 and 772 US$/ha based on the small, medium and large farming scales respectively and 1.13, 1.14 and1.21 respectively as average benefit cost ratio (BCR) of each producer category. These results revealed that the socio economic factors have a profound influence on profitability of rice production. The second group of rice actors is composed by buyer-steamers and is the main beneficiaries of rice value chain; they are able to generate much higher net incomes with an average BCR of 2.85, followed shellers with an average BCR of 1.23. These figures show that the large scale rice producers, and post-harvest processors are the major profitable stakeholders in the rice value chain, whilst small and medium scale rice growers are the groups sharing the small profits from the direct production. Keywords: Rice production, rice value chain, cost- benefice analysis, gross margin analysis, Guinea

Modification of Tillage Implements for Alley Cropping System

Sustainable alley agriculture in the agro-forestry cropping system becomes a great challenge due to the lack of suitable land preparation, using the conventional tillage system “The three-bottom disc plough”. This research is an attempt to modify the conventional tillage implement for better use in agroforestry system. The modified Tillage System, in comparison with 3-bottom disc plough, showed significantly lower tractor actual speed, higher wheel slippage, effective field capacity and higher draught requirements. For the secondary operations, no significant differences were detected between modified tandem and the offset disc harrow, except for the tractor actual speed, where the offset disc harrow resulted in significant higher speed. Moreover, the modified tillage implements shows lower un-ploughed length area within the alley, and two meters increase in the preparation of the available cultivated area compared to the conventional system, and significantly lower bulk density at crop emergence stage only. The modified implements resulted in higher initial and final infiltration rate after seedbed preparation and at harvest in comparison with the conventional system. With regards to crop yield, the modified tillage system resulted in significant higher grain yield in the first and second seasons, in comparison with the use of the conventional tillage system. Keywords: draught requirements, tillage implements, alley cropping, soil cold size, bulk density, superficial lateral root, infiltration rat

Mild cognitive impairment associated with limbic and neocortical lewy body disease: a clinicopathological study

There are little data on the relationship between Lewy body disease and mild cognitive impairment syndromes. The Mayo Clinic aging and dementia databases in Rochester, Minnesota, and Jacksonville, Florida were queried for cases who were diagnosed with mild cognitive impairment between 1 January 1996 and 30 April 2008, were prospectively followed and were subsequently found to have autopsy-proven Lewy body disease. The presence of rapid eye movement sleep behaviour disorder was specifically assessed. Mild cognitive impairment subtypes were determined by clinical impression and neuropsychological profiles, based on prospective operational criteria. The diagnosis of clinically probable dementia with Lewy bodies was based on the 2005 McKeith criteria. Hippocampal volumes, rate of hippocampal atrophy, and proton magnetic resonance spectroscopy were assessed on available magnetic resonance imaging and spectroscopy scans. Eight subjects were identified; six were male. Seven developed dementia with Lewy bodies prior to death; one died characterized as mild cognitive impairment. The number of cases and median age of onset (range) for specific features were: seven with rapid eye movement sleep behaviour disorder—60 years (27–91 years), eight with cognitive symptoms—69 years (62–89 years), eight with mild cognitive impairment—70.5 years (66–91 years), eight with parkinsonism symptoms—71 years (66–92 years), six with visual hallucinations—72 years (64–90 years), seven with dementia—75 years (67–92 years), six with fluctuations in cognition and/or arousal—76 years (68–92 years) and eight dead—76 years (71–94 years). Rapid eye movement sleep behaviour disorder preceded cognitive symptom onset in six cases by a median of 10 years (2–47 years) and mild cognitive impairment diagnosis by a median of 12 years (3–48 years). The mild cognitive impairment subtypes represented include: two with single domain non-amnestic mild cognitive impairment, three with multi-domain non-amnestic mild cognitive impairment, and three with multi-domain amnestic mild cognitive impairment. The cognitive domains most frequently affected were attention and executive functioning, and visuospatial functioning. Hippocampal volumes and the rate of hippocampal atrophy were, on average, within the normal range in the three cases who underwent magnetic resonance imaging, and the choline/creatine ratio was elevated in the two cases who underwent proton magnetic resonance spectroscopy when they were diagnosed as mild cognitive impairment. On autopsy, six had neocortical-predominant Lewy body disease and two had limbic-predominant Lewy body disease; only one had coexisting high-likelihood Alzheimer's disease. These findings indicate that among Lewy body disease cases that pass through a mild cognitive impairment stage, any cognitive pattern or mild cognitive subtype is possible, with the attention/executive and visuospatial domains most frequently impaired. Hippocampal volume and proton magnetic resonance spectroscopy data were consistent with recent data in dementia with Lewy bodies. All cases with rapid eye movement sleep behaviour disorder and mild cognitive impairment were eventually shown to have autopsy-proven Lewy body disease, indicating that rapid eye movement sleep behaviour disorder plus mild cognitive impairment probably reflects brainstem and cerebral Lewy body disease

TDP-43 in Familial and Sporadic Frontotemporal Lobar Degeneration with Ubiquitin Inclusions

TAR DNA-binding protein 43 (TDP-43) is a major pathological protein of sporadic and familial frontotemporal lobar degeneration with ubiquitin-positive, tau-negative inclusions (FTLD-U) with or without motor neuron disease (MND). Thus, TDP-43 defines a novel class of neurodegenerative diseases called TDP-43 proteinopathies. We performed ubiquitin and TDP-43 immunohistochemistry on 193 cases of familial and sporadic FTLD with or without MND. On selected cases, immunoelectron microscopy and biochemistry were performed. Clinically defined frontotemporal dementias (FTDs) included four groups: 1) familial FTD with mutations in progranulin (n = 36), valosin-containing protein (n = 5), charged multivesicular body protein 2B (n = 4), and linked to chromosome 9p (n = 7); 2) familial cases of FTD with unknown gene association (n = 29); 3) sporadic FTD (n = 72); and 4) familial and sporadic FTD with MND (n = 40). Our studies confirm that the spectrum of TDP-43 proteinopathies includes most cases of sporadic and familial FTLD-U with and without MND and expand this disease spectrum to include reported families with FTD linked to chromosome 9p but not FTD with charged multivesicular body protein 2B mutations. Thus, despite significant clinical, genetic, and neuropathological heterogeneity of FTLD-U, TDP-43 is a common pathological substrate underlying a large subset of these disorders, thereby implicating TDP-43 in novel and unifying mechanisms of FTLD pathogenesis