Advanced Journal of Graduate Research
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Maize Response to Sole and Combined Effects of Nitrogen and Nematode Stresses
Get PDFCrops grown on the field or in phytotrons are faced with different biotic stresses including plant-parasitic nematodes (PPNs) and abiotic stresses such as drought and poor soil fertility (low nitrogen levels). In this study, the interactive responses of a low-nitrogen tolerant variety LNTP-YC6 and a regular variety BR-9928-DMRSR to Pratylenchus zeae under four nitrogen-levels: no amendment; [T0], low nitrogen [100kgN/ha NPK; T1], optimum nitrogen [200kgN/ha NPK + Urea; T2] and compost [10t/ha; T3] were investigated. The treatments were arranged in a 2 x 4 factorial fitted into randomised complete block design (RCBD) with four replicates. Data were collected on growth parameters (plant height and stem girth), yield components (number and weight of cobs), lesion score (LS), final nematode population (FNP) and reproductive factor (RF). Low nutrient stress in combination with nematode infection generally reduced maize growth and yield. Growth parameters of BR-9928-DMRSR variety were generally high while yield parameters of LNTP-YC6 variety were significantly greater than in BR-9928-DMRSR variety. However, T2 and T3 improved growth and yield of both maize varieties compared to T0, with T2 being superior to T3. Meanwhile, T3 reduced FNP more than T2. FNP (107.65) and RF (1.3) of P. zeae on LNTP-YC6 variety and with T3 was significantly low compared to T2 (178, 3.34), T0 (188, 3.6) and T1 (217, 5.0). In all the parameters considered, LNTP-YC6 outperformed BR-9928-DMRSR variety. In conclusion, soil amendment with optimum rate of nitrogen and compost reduced nematode population and enhanced maize growth, while low nitrogen in combination with nematode stress reduced maize yield
Proximate, Phytochemical and Antioxidant Mineral Compositions of Four Different Brands of Tea
Get PDFThe comparative studies of the proximate, phytochemical and antioxidant mineral compositions of four different brands of green tea were investigated. The four different brands, Tianshi®, Qualitea®, Slimfit®, and Xiang® were purchased from a supermarket in Ihiala Local Government Area of Anambra State, Nigeria. The samples were pulverized and stored in an airtight container prior to analysis. The proximate composition was analysed using AOAC method while phytochemical compositions of the green teas were investigated using standard methods. The result of the study indicated that the moisture content (15.80±0.01%) and protein content (1.05±0.00%) of Qualitea® was significantly higher (P<0.05) compared to Slimfit and Xiang tea while the fibre content of Xiang tea (80.35±0.03%) was significantly higher (P<0.05) than other tea studied. The phytochemical study showed the presence of flavonoids, tannins, alkaloids, saponins and cardiac glycosides in all the teas studied. However, Qualitea® contains the highest amount of phytochemicals when compared to the other brands of tea investigated. Data obtained from the antioxidant mineral study showed that the four brands of the tea are good sources of antioxidant minerals such as Fe, Zn, Cu, Mn and Se. It is therefore recommended that tea be included in our menu because of their nutritive and health benefits
Mineral and Phytochemical Composition of Cleome Gynandra Methanolic Extract
Get PDFThe study was done to evaluate the mineral and phytochemical composition of the methanolic extract of Cleome gynandra (spider plant). The plant is used as a traditional vegetable in some communities in sub-Saharan Africa and Asia. The plant has also been reported to have some medicinal effect due to presence of phytochemicals but its pharmacological and phytochemical profile has not been fully established. Collection and authentication of the plant was done followed by extraction using methanol as a solvent. The phytochemical investigation was done using both chemical analysis and chromatography method by use of a Gas chromatography mass spectroscopy (GCMS) system as per standard protocol. Cleome gynandra was found to contain some mineral compounds of nutritional importance and phytochemicals with potential medicinal importance. The phytochemicals analyzed include saponins, flavonoids, tannins, alkaloids, cardiac glycosides, terpanoids and polyphenols. These different phytochemicals can be further studied and their potential medicinal importance analyzed. The study concluded that Cleome gynandra contains phytochemicals with potentially important medicinal value. The plant (Cleome gynandra) can also be used as an important nutritional source of some essential nutrients like Vitamin C and beta carotene. It can also be a good source of some mineral elements like iron, selenium, cobalt, copper, zinc and manganese. This can be important for families in rural areas and for the low-income households in both rural and urban areas as a source of nutrients
Power Performance Analysis of PV Module with DC to DC Buck Converter
Get PDFThe power performance of PV module with dc-dc buck converter for photovoltaic energy application has been analyzed in this paper. Since the solar module produces DC voltage at various levels depending on irradiance variation, it is needed to connect a DC-DC converter to adjust the level of DC voltage at a certain level. The power output has been investigated by MATLAB simulation. To improve the output power Proportional Integral Derivative (PID) control is used. From the simulation it has been observed that around 13.85 Watts more output power can be extracted if PID control is used
Assessing the Macronutrient Status of Some Selected Soils in Bayelsa State, South-South Nigeria
Get PDFFertility status of soils within the south-south region of Nigeria varies both inter and intra states. Therefore, the study investigated the macronutrient status of some selected soils in Bayelsa State. Two farm sites in Opume (OPF) and Amassoma (AMF) with records of long term cultivation were randomly selected and soil samples randomly collected from each locality for physico-chemical analyses. Data collected were subjected to statistical analysis of means and a post hoc regression analysis to determine relationships between soils and analyzed parameters. Results revealed that soils were loam to sandy clay loam and acidic with low pH levels. Exchangeable bases (Ca2+, Mg2+, K+) were low in AMF soils compared to OPF soils except for Na+. Organic carbon and organic matter were moderately low in both soils, however, AMF had lower contents. Total N were found to be critically low (0.03%) in both soils. OPF had higher available phosphorus (5.09 mg/kg) while AMF had higher available Sulphur (6.55 mg/kg). Base saturation was moderate in OPF (50.44 %), however, not significantly different (p<0.05) from AMF. Similarly, Effective Cation Exchange Capacity (ECEC) was low in soils of both localities. Regression analysis showed that pH had significant positive relationships with sand, Org C, Org M, available P, TN, % B.S and the basic cations (r=0.534*, 0.841***, 0.837***, 0.855***, 0.736***, 0.856**) with a negative relationship with Exchangeable acidity and SO42- (r=-0.799** and -0.844***). Org C, Org M and TN had significant negative relationships with silt at both localities (r=-0.592**, -0.592** and -0.491*) respectively. These results indicate clearly that the nutrient status of soils in the study areas are mostly controlled by pH and the textural distribution. It also indicates that improved soil management practices can improve the macronutrient status for increased crop production
Trained Immunity at a Glance; A Review on the Innate Immune Memory and its Potential Role in Infections, Diseases and New Therapeutic Strategies
Get PDFDespite the existence of two different branches of immunity, innate and adaptive, it has been described that both systems are characterized by the establishment of memory responses. Indeed, it has been shown that cells belonging to the innate immune system can express a so-called “trained” memory, although it has different features from the adaptive immune memory. Adaptive memory is a long-lasting specific memory whereas innate memory involves non-specific responses which enhance the immune response during a second reinfection. However, many aspects of the trained immunity are still unclear. Metabolic and epigenetic reprogramming have been pointed as the two processes responsible for the establishment of the innate memory. Trained immunity seems to be responsible for the heterologous effect of many vaccines such as BCG, thus giving insights for the development of new therapies. Although its potential beneficial role, trained immunity could also have detrimental effects that might worsen the progress of certain diseases. The purpose of this literature review is to provide an in-depth review on the major characteristics of trained immunity, describing the main pathways at the basis of the evolution and establishment of memory in innate cells. In addition, the present review assesses the modern evidence of the impact of trained immunity in health and disease, strengthening the hypotheses that this innate memory may be considered both in the formulation of new therapeutic strategies and in the current therapeutic approaches.
Static, Free Vibration and Buckling Analysis of Composite Panels; A Review
Get PDFA composite material is generally a combination of materials differing in composition or form on a macro scale for the purposes of attaining specific characteristics and properties. The developments in the field of composite materials have granted significant weight reduction in structural design. When compared to metallic materials, composites offer many advantages, especially high strength, stiffness to weight ratio, excellent fatigue properties, and corrosion resistance. Plates, curved panels, the cylindrical shell-shaped forms of models are being broadly used in many structural packages of engineering structure. For design the structure, it is important to know the behaviour of these under static, free vibration, buckling condition. The present paper aims to review the literature on static, free vibration, and buckling analysis of composite flat panel, curved panel, and cylindrical shell. Further, the testing procedure of laminate, design guidelines of laminates and cost estimations with mechanical properties comparison of laminate with metal, CLT (classical lamination theory) basis including thermal and moisture expansion for stiffness evaluation are also summarised in this paper
Solar Dynamical Processes II
Get PDFThe present article is the successor of Solar Dynamical Processes I. The previous article was focused on the Sun, its magnetic field with an emphasis on various dynamical processes occurring on the Sun, e.g. sunspots, prominence and bright points which in turn plays a fundamental role in regulating the space weather. This article is emphasized on the solar dynamical processes and develop an extensive understanding of the various phenomena involved in their origin. The article also covers various models and hypothesis put forward by pioneer scientists on the basis of their observation by space-borne and ground-based instruments. This article shade light over a wide range of dynamical processes e.g., solar flares, coronal mass ejections, solar jets and coronal holes. Solar jets, the small-scale transient activities are found to have association with the other transient activities (e.g., mini-flares and mini-filaments). Flares as well as the coronal mass ejections are responsible for releasing a large amount of high energy charged particles and magnetic flux into the interplanetary space and are being considered as the main drivers of space weather
Mechanical and Physical Properties of Polyester Reinforced Glass Fibre/Orange Peel Particulate Hybrid Composite
Get PDFThis study was focused on the development of hybrid composed using orange peel particulate dispersed in an unsaturated polyester resin reinforced with chopped strands of E-glass fibers. Orange peel particulate of about 350µm sieve size, of varying weight percentage (3, 6, 9,12 and 15) wt.% and E-glass fiber of constant weight percentage 25.1wt% was used as reinforcements in a polyester matrix. The effect of the orange peel particulate on the physical and mechanical properties of the resulting composite such as tensile strength, bending strength, impact strength and hardness strength was investigated. The results showed remarkable improvement in mechanical properties with increase in percentage of particulate reinforcement. Tensile strength varies from 50.0 to 62.6 MPa, Hardness values varies between 28.6 and 40.8HRB, Impact energy at room temperature, varies between 5.0 to 7.4 Joules, as a function of fiber weight fractions and the flexural strength varies from 74.0 to 85.2 MPa. The best mechanical properties were obtained at 15 Wt.% particulate reinforcements. The results of the physical tests show that the water absorption increases as the weight percentage of the particulate reinforcement increases and the same condition also holds for the density
Direct Carbon Fuel Cell-Cleaner and Efficient Future Power Generation Technology
Get PDFIncreasing greenhouse effect due to the burning of fossil fuels has stirred the attention of researchers towards cleaner and efficient technologies. Direct carbon fuel cell (DCFC) is one such emerging technology that could generate electricity from solid carbon like coal and biogas in a more efficient and environmental-friendly way. The mechanism involves electrochemical oxidation of carbon to produce energy and highly pure carbon dioxide. Due to higher purity, the produced carbon dioxide can be captured easily to avoid its release in the environment. The carbon dioxide is produced in a gaseous state while the fuel used is in a solid state. Due to different phases, all of the fuel can be recovered from the cell and can be reused, ensuring complete (100%) fuel utilization with no fuel losses. Moreover, DCFC operates at a temperature lower than conventional fuel cells. The electric efficiency of a DCFC is around 80% which is nearly double the efficiency of coal thermal plant. In addition, DCFC produces pure carbon dioxide as compared to the thermal power plant which reduces the cost of CO2 separation and dumping. In different types of DCFCs, molten carbon fuel cell is considered to be superior due to its low operating temperature and high efficiency. This paper provides a comprehensive review of the direct carbon fuel cell technology and recent advances in this field. The paper is focused on the fundamentals of fuel cell, history, operating principle, its types, applications, future challenges, and development