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On the shape and fate of our Universe
Get PDFEinstein’s special and general theories of relativity revolutionized physics and cosmology. Newton assumed four identities namely mass, energy, space, and time. He told that space is absolute. Einstein modified and refined Newtonian concepts s by postulating that mass-energy and space-time. This enabled Einstein to find special relativity theory which predicted the variance of mass with velocity, the equivalent of mass and energy, time dilation, and length contraction. The extension and generalization of special relativity theory is the outcome of general relativity theory which is the geometrical interpretation of gravity. Almost all the predictions of Einstein’s general relativity theory have been experimentally verified. By delving into the equations of general relativity, the famous Russian mathematician Alexander Freedman found that the geometry of our Universe has only three possibilities, namely, open, closed, and flat. Freedman’s publication in the 1920s paved the way to study the geometry and fate of our Universe. Recently, NASA’s WMAP spacecraft and ESA’s Planck probes and observations revealed that the geometry of our Universe is flat with a marginal error of 0.04%. But to this day, there is no mathematical proof for these observations. In this short work, by applying the multiplication and division laws of number theory to cosmic triangles the author attempts to show that the shape/geometry of our Universe is FLAT.</p
Proteomic analysis of a copper mine isolated fungus Rhizopus microspores IOC 4686 when exposed to copper sulfate
Get PDFThe fungus Rhizopus microsporus, known for its absorption capacity for toxic metals was used to understand the green metal recovery via analysis of its physiology under metal stress conditions through proteomic methods. To investigate the effects of copper stress on fungus, R. microsporus IOC 4686, isolated from the mine environment, was exposed to copper ions (50mgL-1) for 48 h. This study was performed only on copper exposure. Tryptic and chymotryptic extracts of proteins were analyzed by nano- liquid chromatography-tandem mass spectrometry, identification was performed by PEAKS Studio 8.5. Proteins were classified according to their molecular function and biological process. Enzymes, such as catalase, superoxide dismutase, and cytochrome c peroxidase were found in the presence and absence of copper ions. However, only in presence of copper ions, was observed the presence of heat shock proteins (HPS 20, HPS 70, and HPS 78) and metalloproteins (GrpE protein homolog and cytochrome P450). These classes of proteins have been produced by cells in response to stress conditions. The control group (absence of copper ions) also presented antioxidant enzymes suggesting that the fungus isolated from the mine environment already has adapted to the copper. The presence of these proteins suggested a physiological response of R. microsporus IOC 4686 to oxidative stress induced by copper.</p
Expression of PAR2 and NF-κB in human primary dental pulp odontoblasts during the progression of caries
Get PDFIncreased proteinase-activated receptor-2 (PAR2) expression is observed in various diseases related to inflammation. However, the expression of PAR2 in odontoblasts in response to dental caries has not been investigated. Therefore, to explore the functions of odontoblasts during the progression of carious infection, we measured PAR2 and NF-κB expression using immunofluorescence techniques in the odontoblast layer and pulpocytes in the sub-odontoblast region of 44 teeth extracted from children undergoing dental treatment (eight sound samples, 13 early carious samples, 16 advanced carious samples, and eight exposed pulp samples). PAR2 and NF-κB were expressed at moderate levels in sound teeth with non-carious pulp, and the expression levels changed as caries progressed. PAR2 was significantly upregulated in the odontoblast layer during early-stage and advanced-stage caries, and reduced below healthy levels in teeth with exposed pulp. NF-κB was significantly upregulated in early-stage caries and significantly downregulated in advanced-stage and late-stage caries. Moreover, in the sub-odontoblast region, NF-κB expression increased with the progression of caries. Overall, this study suggests PAR2 may represent a crucial cell signalling receptor in the dentine-pulp complex during dental inflammation, and that NF-κB may be one of the key pathways that regulate inflammatory immune responses in the dental pulp. </p
Strategies to fight COVID-19: Beyond the difference between SARS-CoV-2 and Influenza virus
Get PDFBackground: Since the outbreak of COVID-19 emerged in Wuhan, China, in December 2019, the epidemic has spread worldwide and posed a great threat to society. Despite great achievements in COVID-19 research, few studies have focused on the similarities and differences between SARS-CoV-2 and influenza viruses. Results: Through a review of the literature on SARS-CoV-2 and influenza viruses, we found that influenza occurs every year, and influenza pandemics occur irregularly. The uncomplicated human influenza viruses primarily affect the larger airways and rarely the alveoli. However, SARS-CoV-2 mainly involves the deep airways and lungs and can cause DAD, leading to severe hypoxemia. In general, SARS-CoV-2 is no less infectious than the influenza virus. However, its destructive power to the lungs is no less than the avian influenza virus. There is currently no clinical vaccine and specific inhibitor against SARS-CoV-2.Conclusions: SASR-CoV-2 damages lung function more severely than the influenza virus, with higher morbidity, mortality, and severe disease rates. Controlling the source of infection, cutting off the route of transmission, and protecting susceptible populations are critical to the fight against SARS-CoV-2.</p
The mining of cobalt must meet the highest environmental and health standards
Get PDFIn an effort to combat climate change there is a major rush to eliminate the use of fossil fuels. However, this must be done in an orderly process to avoid stressing an already overstressed planet. The push for electric cars and lithium batteries requires intensive mining to extract the heavy metals needed to meet increasing global demands. This is in addition to the already staggering increase in the worldwide usage of digital devices and electronics that require the same metals. Heavy metals such as nickel, chromium, iron, zinc, manganese and cobalt, at very low concentrations, are all essential to the growth and development of plants [1-3]. </p
Weyl conformal symmetry for gravitation and cosmology
Get PDFThe novel paradigm of universal conformal symmetry has been found to explain accelerating Hubble expansion, centripetal lensing by dark galactic halos, and observed excessive galactic rotational velocities, without dark matter. </p
Sound Energy Harvesting and Converting Electricity (SEHCE)
Get PDFThe research study “Sound Energy Harvesting and Converting Electricity (SEHCE)” aims to create a better and easier way of producing another source of clean and renewable energy through sound. The study did not aim to be compared to other proven sources of electricity such as heat, wind, solar and hydroelectric, instead, it was created to find and explore new ways of producing an alternative source of energy. The project will undergo several processes such as designing, construction, testing, and evaluation. Through this, the researcher will be able to find out that sound energy can be converted to electricity.</p
A comparison between major chemical markers of the cultivated and wild harvested Siphonochilus aethiopicus, African ginger, from Mpumalanga, South Africa, using Liquid Chromatography-Mass Spectrometry
Get PDFSiphonochillus aethiopicus, known as African ginger, is indigenous to South Africa and has multiple traditional uses in health to treat human diseases. The multiple traditional uses of African ginger have exacerbated the over-harvesting of the plant species from the wild for trade on the traditional medicine market. The wild populations of African ginger have almost completely depleted from the wild and a few African ginger cultivation sites have been established in South Africa, to conserve the plant species. The aim of the study was to compare the major chemical markers of the cultivated and wild harvested African ginger from Mpumalanga using Liquid Chromatography-Mass Spectrometry (LC-MS). The Council for Scientific and Industrial Research (CSIR) wild-harvested African ginger dated 2010 was used as a reference sample for comparison purposes. The LC-MS data generated from the ethanol extracts of the cultivated African ginger detected the presence of 4,4a,5,8a,9-tetrahydro-3,5,8a-trimethylnaptho[2,3-b]furan-8. This chemical marker was also detected in the wild harvested African ginger as compared to a previous study, which auto oxidised in the referenced sample over time. This study supports the efforts to conserve African ginger through cultivation for further development in commercialisation. </p
Different approaches to the protection and enhancement of underwater archaeological sites: Acquirements and Aspirations
Get PDFThis paper presents aspects of underwater cultural heritage management in Greece, focusing mainly on accessibility to the diving community and the general public. More specifically, it discusses different approaches to the protection and enhancement of Underwater Archaeological Sites, already put into practice over the last years (2018-2021) by the Ephorate of Underwater Antiquities, the public service of the Hellenic Ministry of Culture and Sports responsible for the management of underwater heritage. Moreover, it analyses the aspirations for the future, as these took shape already at the beginning of 2021. Lately, cultural management has turned into a fast-growing sector with multilevel developmental prospects. In order to tap into the underwater cultural heritage potential, we must always take into consideration the identity and special characteristics of each underwater site as well as the different possibilities of access — physical or virtual — that are rapidly changing because of new technological achievements. All these parameters affect significantly decision making and the undertaking of relevant initiatives. Examples of the pilot implementation of the opening of underwater archaeological/cultural sites to the public will be presented. Through them, preliminary conclusions concerning the efficacy of the selected managerial approaches can be drawn, while at the same time domains where more should be done will be highlighted.</p
Research status and development trend of altruism in the biological field - knowledge graph analysis based on <em>CiteSpace</em>
Get PDFBased on the visualization analysis of foreign literature on altruistic behavior in recent ten years (2012-2022) by CiteSpace, it is found that the research on altruistic behavior in the field of biology abroad has experienced the initial exploratory stage, the outbreak stage, and now enters the stable and deepening stage. The discipline distribution is mainly behavioral ecology, supplemented by evolutionary biology, biomathematics, and genetics. The author has three main cooperative groups, and a relatively tight cooperative network has been formed locally in related fields. From the perspective of cooperation degree, the cooperation density of major research institutions is high, and relevant research has been relatively mature. Judging from the period calculated in the software, altruism, cooperation, kin Selection, reciprocity, and inclusive fitness emerged earlier. In recent years, constitutive theory, density dependence, and Habitat construction have emerged, which may become a new direction for future research. Therefore, future research can expand the scope of disciplines, strengthen the cooperation between authors and units, and explore other research hotspots.</p