Energy Harvesting and Modeling of Photosynthetic Power Cell

The need for energy is inevitable for mankind. Climate change, depletion of natural resources, pollution and other factors have created the necessity to look for energy from renewable sources. Furthermore, there are challenges aplenty in the field of renewable energy as renewable energy sources are unpredictable, non-dependable and limited such as wind, solar photo voltaic and tidal power. Apart from these there are few unconventional renewable energy sources that have not been explored thoroughly or exploited. The photosynthetic power cell is one among them. The photosynthetic power cell (PSC) harvests the energy produced at the lowest level of the food cycle which is “photosynthesis” in plants. The photosynthetic power cell extracts the energy produced during photosynthesis and respiration in form of electrical energy. The developed device differs from other published works in terms of improved performance, fabrication technique and material of structure. The two main types of sources used in the photosynthetic power cell are aerobic unicellular organisms (e.g. algae and cyanobacteria) and sub-cellular thylakoid photosystems / chloroplasts isolated from plant cells (e.g. spinach plant’s sub-cellular thylakoid photosystems isolated from the plant cells). The photosynthetic power cell produces energy under both dark and light conditions. The developed PSC is a polymer based structure instead of silicon, integrating the conventional MEMS processes with polymers. The principle of the operation of the device is based on ‘photosynthesis’. Photosynthesis and respiration both involve electron transfer chains. The electrons are extracted with the help of electrodes and a redox agent, and a power electronic converter is designed to harvest the energy. The developed device is capable of producing an open circuit voltage of 0.9 volts and about 200 μW of peak power. The μPSC has an active area of 4.84 cm2 which approximately translates to a power density of 400 mW/m2. This makes it as one of the best performing μPSC. The other top performing μPSC devices report power densities between 100 to 250 mW/m2. In order to harvest energy from μPSC, power electronic converters are a necessity. Three different power electronic topologies are investigated to find the feasibility of energy harvesting using μPSC. Also, the cell should be operated at the maximum power point in order to get the best results. Common maximum power point tracking (MPPT) techniques as well as a novel MPPT technique is devised and tested for the energy harvesting application using μPSC. In this thesis work, the device’s working principle, fabrication of the device and testing of the developed prototype along with the design and development of the power electronic converters with MPPT algorithm for energy harvesting application with μPSC are presented. A short introduction, basic photosynthesis process, background and history of μPSC are discussed in first chapter. The cell design, construction, working and fabrication of the cell are discussed in the second chapter. The third chapter deals with the experimental set up, characterization and testing of the cell. In the fourth chapter, modeling, analysis, simulation of PSC is executed. Analysis, identification and simulation of suitable power electronic converters with MPPT are investigated in the fifth chapter. Conclusions, future work form the epilogue

Organic acid production in vitro and plant growth promotion in maize under controlled environment by phosphate-solubilizing fluorescent Pseudomonas

BACKGROUND: Phosphorus deficiency is a major constraint to crop production due to rapid binding of the applied phosphorus into fixed forms not available to the plants. Microbial solubilization of inorganic phosphates has been attributed mainly to the production of organic acids. Phosphate-solubilizing microorganisms enhance plant growth under conditions of poor phosphorus availability by solubilizing insoluble phosphates in the soil. This paper describes the production of organic acids during inorganic phosphate solubilization and influence on plant growth as a function of phosphate solubilization by fluorescent Pseudomonas. RESULTS: Nineteen phosphate-solubilizing fluorescent Pseudomonas strains of P. fluorescens, P. poae, P. trivialis, and Pseudomonas spp. produced gluconic acid, oxalic acid, 2-ketogluconic acid, lactic acid, succinic acid, formic acid, citric acid and malic acid in the culture filtrates during the solubilization of tricalcium phosphate, Mussoorie rock phosphate, Udaipur rock phosphate and North Carolina rock phosphate. The strains differed quantitatively and qualitatively in the production of organic acids during solubilization of phosphate substrates. Cluster analysis based on organic acid profiling revealed inter-species and intra-species variation in organic acids produced by Pseudomonas strains. The phosphate-solubilizing bacterial treatments P. trivialis BIHB 745, P. trivialis BIHB 747, Pseudomonas sp. BIHB 756 and P. poae BIHB 808 resulted in significantly higher or statistically at par growth and total N, P and K content over single super phosphate treatment in maize. These treatments also significantly affected pH, organic matter, and N, P, and K content of the soil. CONCLUSION: The results implied that organic acid production by Pseudomonas strains is independent of their genetic relatedness and each strain has its own ability of producing organic acids during the solubilization of inorganic phosphates. Significant difference in plant growth promotion by efficient phosphate-solubilizing Pseudomonas strains point at the need for selecting potential strains in plant growth promotion experiments in conjunction with various phosphate substrates for their targeted application as bioinoculants

Knowledge, attitude, and practices in response to COVID-19 pandemic in Indian population

Background: The World Health Organization (WHO) had reported COVID-19 disease as a pandemic in March 2020, following which India witnessed more than 29,451 cases on 29th April. Correct knowledge about the disease, the right attitude, and response to infection control recommendations among people is of utmost importance to limit the contagion.Methods: A Cross-Sectional, web-based online study was conducted for five days. The responses (N= 1231) were collected across social networks using snowball sampling. The survey questionnaire assessed the knowledge, attitude, and practical aspects of participants for COVID-19. Knowledge items assessed the causative agent of COVID-19, it’s clinical symptoms, routes of transmission, preventive measures etc. Positive or negative attitudes towards mask usage and restriction compliance were assessed. Socio-demographic data and scores were de-identified and analyzed using appropriate statistical tests.Results: The mean age of participants (N=1231) was 32.3±13.7 years and 60.9% were males. High knowledge years and 60.9% participants were males. High knowledge accuracy rate of 84.5% and a mean score of 10.19±1.6 out of 12 was observed. Mean attitude and practice scores were 2.33±0.66 (3) and 1.97±0.16 (2) respectively. A significantly higher knowledge status was observed among females, medical workers, students, and homemakers. Similarly, better attitudes were noticed in males, adults (30-60 years), graduates, and those in job/service. As for practices, no such difference was noticed as more than 98% of participants were compliant to lockdown restrictions and practiced proper distancing and personal hygiene measures.Conclusions: Satisfactory awareness and response were observed owing to the public awareness campaign. Knowledge gaps, poor attitudes, and prevailing myths need to be addressed through targeted communication strategy.

Primary accumulation in the Soviet transition

The Soviet background to the idea of primary socialist accumulation is presented. The mobilisation of labour power and of products into public sector investment from outside are shown to have been the two original forms of the concept. In Soviet primary accumulation the mobilisation of labour power was apparently more decisive than the mobilisation of products. The primary accumulation process had both intended and unintended results. Intended results included bringing most of the economy into the public sector, and industrialisation of the economy as a whole. Unintended results included substantial economic losses, and the proliferation of coercive institutions damaging to attainment of the ultimate goal - the building of a communist society

Higher order antibunching in intermediate states

Since the introduction of binomial state as an intermediate state, different intermediate states have been proposed. Different nonclassical effects have also been reported in these intermediate states. But till now higher order antibunching or higher order subpoissonian photon statistics is predicted only in one type of intermediate state, namely shadowed negative binomial state. Recently we have shown the existence of higher order antibunching in some simple nonlinear optical processes to establish that higher order antibunching is not a rare phenomenon (J. Phys. B 39 (2006) 1137). To establish our earlier claim further, here we have shown that the higher order antibunching can be seen in different intermediate states, such as binomial state, reciprocal binomial state, hypergeometric state, generalized binomial state, negative binomial state and photon added coherent state. We have studied the possibility of observing the higher order subpoissonian photon statistics in different limits of intermediate states. The effect of different control parameters have also been studied in this connection and it has been shown that the depth of nonclassicality can be tuned by controlling various physical parameters.Comment: 12 Pages LaTeX 2e, 11 figure

Generalized structure of higher order nonclassicality

A generalized notion of higher order nonclassicality (in terms of higher order moments) is introduced. Under this generalized framework of higher order nonclassicality, conditions of higher order squeezing and higher order subpoissonian photon statistics are derived. A simpler form of the Hong-Mandel higher order squeezing criterion is derived under this framework by using an operator ordering theorem introduced by us in [J. Phys. A. 33 (2000) 5607]. It is also generalized for multi-photon Bose operators of Brandt and Greenberg. Similarly, condition for higher order subpoissonian photon statistics is derived by normal ordering of higher powers of number operator. Further, with the help of simple density matrices, it is shown that the higher order antibunching (HOA) and higher order subpoissonian photon statistics (HOSPS) are not the manifestation of the same phenomenon and consequently it is incorrect to use the condition of HOA as a test of HOSPS. It is also shown that the HOA and HOSPS may exist even in absence of the corresponding lower order phenomenon. Binomial state, nonlinear first order excited squeezed state (NLESS) and nonlinear vacuum squeezed state (NLVSS) are used as examples of quantum state and it is shown that these states may show higher order nonclssical characteristics. It is observed that the Binomial state which is always antibunched, is not always higher order squeezed and NLVSS which shows higher order squeezing does not show HOSPS and HOA. The opposite is observed in NLESS and consequently it is established that the HOSPS and HOS are two independent signatures of higher order nonclassicalityComment: 14 pages, 7 figure

Ligand-activated BMP signaling inhibits cell differentiation and death to promote melanoma

Oncogenomic studies indicate that copy number variation (CNV) alters genes involved in tumor progression; however, identification of specific driver genes affected by CNV has been difficult, as these rearrangements are often contained in large chromosomal intervals among several bystander genes. Here, we addressed this problem and identified a CNV-targeted oncogene by performing comparative oncogenomics of human and zebrafish melanomas. We determined that the gene encoding growth differentiation factor 6 (GDF6), which is the ligand for the BMP family, is recurrently amplified and transcriptionally upregulated in melanoma. GDF6-induced BMP signaling maintained a trunk neural crest gene signature in melanomas. Additionally, GDF6 repressed the melanocyte differentiation gene MITF and the proapoptotic factor SOX9, thereby preventing differentiation, inhibiting cell death, and promoting tumor growth. GDF6 was specifically expressed in melanomas but not melanocytes. Moreover, GDF6 expression levels in melanomas were inversely correlated with patient survival. Our study has identified a fundamental role for GDF6 and BMP signaling in governing an embryonic cell gene signature to promote melanoma progression, thus providing potential opportunities for targeted therapy to treat GDF6-positive cancers

Acute Intermittent Porphyria: A Frequently Misdiagnosed Chameleon!

Acute intermittent porphyria (AIP) is an inborn disorder of heme biosynthesis, autosomal dominant in inheritance. It is a frequent occurrence in young females of reproductive age group. While abdominal pain is the most frequent presentation of this disorder, it can present with a myriad of clinical and biochemical features, frequently leading to misdiagnosis of this condition. We present a case of a 17-year-old young female who presented with an acute onset weakness in all four limbs along with absent deep tendon reflexes but characteristically preserved ankle jerks, who was initially diagnosed as Guillain-Barré syndrome (GBS), treated with intravenous immunoglobulin (IVIg), succumbed to a chronic progressive course of weakness and put on oral steroids. Lack of improvement and subsequent development of abdominal pain led us to investigate her for urine for porphobilinogen which came out to be positive, thus leading to a final diagnosis of AIP

Organic acid production in vitro and plant growth promotion in maize under controlled environment by phosphate-solubilizing fluorescent Pseudomonas

Background: Phosphorus deficiency is a major constraint to crop production due to rapid binding of the applied phosphorus into fixed forms not available to the plants. Microbial solubilization of inorganic phosphates has been attributed mainly to the production of organic acids. Phosphate-solubilizing microorganisms enhance plant growth under conditions of poor phosphorus availability by solubilizing insoluble phosphates in the soil. This paper describes the production of organic acids during inorganic phosphate solubilization and influence on plant growth as a function of phosphate solubilization by fluorescent Pseudomonas. Results: Nineteen phosphate-solubilizing fluorescent Pseudomonas strains of P. fluorescens, P. poae, P. trivialis, and Pseudomonas spp. produced gluconic acid, oxalic acid, 2-ketogluconic acid, lactic acid, succinic acid, formic acid, citric acid and malic acid in the culture filtrates during the solubilization of tricalcium phosphate, Mussoorie rock phosphate, Udaipur rock phosphate and North Carolina rock phosphate. The strains differed quantitatively and qualitatively in the production of organic acids during solubilization of phosphate substrates. Cluster analysis based on organic acid profiling revealed inter-species and intra-species variation in organic acids produced by Pseudomonas strains. The phosphate-solubilizing bacterial treatments P. trivialis BIHB 745, P. trivialis BIHB 747, Pseudomonas sp. BIHB 756 and P. poae BIHB 808 resulted in significantly higher or statistically at par growth and total N, P and K content over single super phosphate treatment in maize. These treatments also significantly affected pH, organic matter, and N, P, and K content of the soil. Conclusion: The results implied that organic acid production by Pseudomonas strains is independent of their genetic relatedness and each strain has its own ability of producing organic acids during the solubilization of inorganic phosphates. Significant difference in plant growth promotion by efficient phosphate-solubilizing Pseudomonas strains point at the need for selecting potential strains in plant growth promotion experiments in conjunction with various phosphate substrates for their targeted application as bioinoculants

An Unusual Presentation of Bickerstaff Brainstem Encephalitis

Bickerstaff brainstem encephalitis (BBE) is diagnosed by progressive, relatively symmetrical ophthalmoplegia, ataxia, disturbance of consciousness and/or hyperreflexia. Positive anti-GQ1b are found in 66% and abnormal brain MRI in 30% of patients. The classical triad seen in Fisher syndrome is ataxia, ophthalmoplegia and areflexia. If there is associated alteration in the level of consciousness and/or hyperreflexia, a diagnosis of Bickerstaff encephalitis is made due to possible involvement of the central nervous system. Here we report a case of BBE presenting with hyperreflexia without drowsiness as a sign of CNS involvement