757 research outputs found

    Effects of salinity on the growth, photosynthesis and mineral constituents of the mangrove Rhizophora apiculata L. seedlings

    Get PDF
    The effects of salinity on growth, chlorophyll content, photosynthetic rates, as measured by leaf stomatal conductance and leaf chlorophyll fluorescence induction, and ion accumulation in the mangrove plant Rhizophora apiculata were determined. The following questions were addressed:                (1) What effect does salinity have on growth responses at different ages? (2) Is R. apiculata an ion accumulator? (3) Does R. apiculata accumulate chlorophyll, net photosynthesis and chlorophyll fluorescence in response to salinity? Rhizophora apiculata  plants were grown in pots at 0, 25, 50, 75 and 100 % in sand culture in a plant growth chamber and plants were harvested after 30 and 90 d. Plant total fresh and dry weight and moisture content was significantly inhibited at 75 per cent seawater. Seawater salinity stimulated the chlorophyll contents and they were increased upto 75 per cent seawater.  The net photosynthesis increased with increasing salinity upto the optimal level and the CO2 uptake rate was identical in this species at various salt concentrations. Even at extreme salinity, the CO2 uptake was comparable to that non-saline control plants and CO2 uptake could be correlated with the chlorophyll content. The photochemical activities such as PSI and PSII of the isolated cells increased upto the optimal salinity. The result of the chlorophyll fluorescence kinetics provided with additional proof to the finding of CO2 exchange rate and photochemical activities.  The Na+ and Cl− content in both shoots and roots increased with increases in salinity. Increased treatment levels of NaCl induced decreases in Ca+, P, K+, Mg+   and N in plants

    Antibacterial Activity of Salicornia brachiata, A Halophyte

    Get PDF
    Antibacterial activity of Salicornia brachiata was studied by the agar diffusion and dilution methods.  The methanolic extract of leaves of this species was more active than the aqueous extracts against Bacillus subtilis, Bacillus pumilus, Micrococcus luteus and Staphylococcus aureus.ÂÂ

    An Implementing A Continuous Authentication Protocol To Improve Robustness Security Threats On IoT Using ESP8266

    Get PDF
    The Internet of Things (IoT) is a network of physical things that are outfitted with sensors, software, and other technologies that are able to communicate and exchange data with other devices and systems over the Internet. Because of the diversity of their surroundings, IoT systems are sensitive to network attacks. The IoT could be the source of these dangers and attacks. There are a lot of devices that communicate with each other via the IoT, and one of the most critical components of this is to maintain IoT security. IoT devices are a prime target for attackers and pose a serious risk of impersonation during a call. Proposals to prevent session hijacking in device-to-device communication are made in this research study. User-to-device authentication relies on usernames and passwords, but continuous authentication doesn't. This protocol relies on device features and contextual information. Moreover, this protocol reduces the synchronization losses using shadow IDs and emergency key. In addition, the protocol’s robustness will be tested by providing security and performance analysis

    Improvement of voltage stability for grid connected solar photovoltaic systems using static synchronous compensator with recurrent neural network

    Get PDF
    Purpose. This article proposes a new control strategy for static synchronous compensator in utility grid system. The proposed photovoltaic fed static synchronous compensator is utilized along with recurrent neural network based reference voltage generation is presented in grid system network. The novelty of the proposed work consists in presenting a Landsman converter enhanced photovoltaic fed static synchronous compensator with recurrent neural network algorithm, to generate voltage and maintain the voltage-gain ratio. Methods. The proposed algorithm which provides sophisticated and cost-effective solution for utilization of adaptive neuro-fuzzy inference system as maximum power point tracking assures controlled output and supports the extraction of complete power from the photovoltaic panel. Grid is interconnected with solar power, voltage phase angle mismatch, harmonic and voltage instability may occur in the distribution grid. The proposed control technique strategy is validated using MATLAB/Simulink software and hardware model to analysis the working performances. Results. The results obtained show that the power quality issue, the proposed system to overcome through elimination of harmonics, reference current generation is necessary, which is accomplished by recurrent neural network. By recurrent neural network, the reference signal is generated more accurately and accordingly the pulses are generated for controlling the inverter. Originality. Compensation of power quality issues, grid stability and harmonic reduction in distribution network by using photovoltaic fed static synchronous compensator is utilized along with recurrent neural network controller. Practical value. The work concerns the comparative study and the application of static synchronous compensator with recurrent neural network controller to achieve a good performance control system of the distribution network system. This article presents a comparative study between the conventional static synchronous compensator, static synchronous compensator with recurrent neural network and hardware implementation with different load. The strategy based on the use of a static synchronous compensator with recurrent neural network algorithm for the control of the continuous voltage stability and harmonic for the distribution network-linear as well as non-linear loads in efficient manner. The study is validated by the simulation results based on MATLAB/Simulink software and hardware model.Мета. У статті пропонується нова стратегія управління статичним синхронним компенсатором в енергосистемі. Запропонований статичний синхронний компенсатор з живленням від фотоелектричних елементів використовується разом з генератором опорної напруги на основі нейронної рекурентної мережі, представленим в мережі енергосистеми. Новизна запропонованої роботи полягає у поданні статичного синхронного компенсатора з покращеним фотоелектричним перетворювачем Ландсмана з алгоритмом рекурентної нейронної мережі для генерації напруги та підтримки коефіцієнта посилення за напругою. Методи. Запропонований алгоритм, який забезпечує ефективне та економічне рішення для використання адаптивної нейро-нечіткої системи логічного виведення як відстеження точки максимальної потужності, забезпечує контрольований вихід та підтримує вилучення повної потужності з фотогальванічної панелі. Мережа взаємопов’язана із сонячною енергією, у розподільній мережі можуть виникати невідповідність фазового кута напруги, гармоніки та нестабільність напруги. Запропонована стратегія методу управління перевіряється з використанням моделей програмного забезпечення MATLAB/Simulink та апаратного забезпечення для аналізу робочих характеристик. Результати. Отримані результати показують, що проблема якості електроенергії, яку запропонована система долає за допомогою усунення гармонік,потребує генерації еталонного струму, що здійснюється рекурентною нейронної мережею. За допомогою рекурентної нейронної мережі більш точно формується еталонний сигнал і відповідно генеруються імпульси для керування інвертором. Оригінальність. Компенсація проблем з якістю електроенергії, стабільністю мережі та зниженням гармонік у розподільній мережі за допомогою статичного синхронного компенсатора з фотоелектричним живленням використовується разом із контролером рекурентної нейронної мережі. Практична цінність. Робота стосується порівняльного дослідження та застосування статичного синхронного компенсатора з рекурентним нейромережевим контролером для досягнення хорошої продуктивності системи управління системою розподільної мережі. У цій статті представлено порівняльне дослідження традиційного статичного синхронного компенсатора, статичного синхронного компенсатора з рекурентною нейронною мережею та апаратною реалізацією з різним навантаженням. Стратегія, що ґрунтується на використанні статичного синхронного компенсатора з рекурентним алгоритмом нейронної мережі для ефективного контролю стабільності постійної напруги та гармонік для лінійних та нелінійних навантажень розподільної мережі. Дослідження підтверджується результатами моделювання з урахуванням програмно-апаратної моделі MATLAB/Simulink

    Evaluation of neck shaft angle and ante version in dry femorae of adult Indian population

    Get PDF
    INTRODUCTION : The proximal end of the femur has been the object of much attention. Knowledge of its anatomy is a prerequisite for a complete understanding of the mechanics of the hip joint and serves as a basis for the treatment of pathological conditions of the hip and femur. Extensive studies of normal neck angles have been carried out. The values differ considerably in the reports available. Differences in methods used, differing anatomical definitions and variations between populations may account for this. AIM : To evaluate the possible variation in the measurements of neck shaft angle and ante version by Direct ,X-ray and CT –guided values in dry femorae of adult Indian population. This correlation of measurements will help us to identify a simple, reliable radiological method to evaluate the proximal femoral angles and the data obtained in this study will help us to improve the implant and prosthesis design for Indian population and enhance the functional outcome of the patient. Study type: analytical observational study – cross sectional type. MATERIALS AND METHODS: 50 unpaired adult dry femorae of undetermined age and sex without gross pathology and abnormality from anatomy department, MMC will be used as the study material. Immature bones, bones with abnormal pathology were excluded from the study. ANTEVERSION: Direct measurements by Kingsley Olmsted method X-ray measurements were taken in dry femur by the method described by KOSUKE OGATA et al- Biplanar radiography method-from AP view and Lateral view of dry femur. CT –measurements of anteversion were taken by measuring the angle between neck horizontal axis and condylar horizontal axis in dry femur scannogram. NECK –SHAFT ANGLE: The collo diaphyseal angle between the head neck axis and the femoral shaft axis measured by direct, X-rays and CT methods. RESULTS: The mean anteversion angle by Direct, X-ray and CT measurements was found to be 10.3⁰, 10.4⁰, 9.9⁰ respectively. Among the three methods the CT-guided method seems to be more accurate to measure the ante version angle by Friedman test result. There was no significant difference in which side (right/left) the sample bone belongs to. The mean neck shaft angle by Direct, X-ray and CT measurements was found to be 131.9± 5.3, 130.3±4, 133.9±5 respectively. Among the three methods the X-ray method seems to be more accurate to measure the neck shaft angle by Friedman test result. There was no significant difference between right and left side bones. CONCLUSION: 1. The simple biplanar radiography can be substituted as an alternative for CT measurements to determine the NSA and AV preoperatively, though CT – measurements give more accurate values. 2. The data obtained forms a strong base for future research in proximal femoral angles in adult Indian population. 3. The proximal femur angles varies for each person even in Indian population and the implants designed are mainly based on the data obtained from western population. These radiological methods helps us to obtain pre operative proximal femur angles to design specific implants to improve the efficiency of fracture fixation and functional outcome

    Metabolic Syndrome and the Management : An appraisal with Siddha System of Medicine

    Get PDF
    Visceral obesity syndrome also known as metabolic syndrome X is the bunch of medical conditions characterised by hypertension, hyperglycaemia, dyslipidemia and atherosclerotic cardiovascular disease affecting, nearly 240 million people worldwide. In India nearly 10000 people were affected per year and overall it goes on escalating steadily due to amplified adulterated human behaviours. There is a need of exigency at this juncture by knowing its complex pathology to condense human anguish and financial load. Siddha system of medicine primarily describes as it may arise due to provocation of the humours of the body. When our moral code of demeanour is deprived including intemperance and deficit physical activity, there is a flawed tissue metabolism leading to metabolic syndrome (MS). Classical books of Siddha were used for literary survey and databases were also analysed with the prime terminology “Metabolic syndrome” for this systemic review. The speculative backdrop, broad set of strategy in aetiology, pathogenesis and management of MS are discussed at extent through Siddha system, in the paper which would be creditable in managing in an effectual and gainful approach

    Amendments food waste compost on soil enzymatic activities in groundnut cultivated soil, India

    Get PDF
    Soil enzymes are play an important role in organic soil. Soil microbes enhances the enzymatic activities .Which is very beneficial to solubilizing the nutrients in the soil. In the present investigation was to find out the activity of soil enzymes such as acid phosphatase, alkaline phosphatase, dehydrogenase and to find the fresh weight of groundnut pods in the addition of food waste compost
    corecore