A Method for Dynamic Characterization and Response Prediction Using Ground Vibration Test(GVT)Data for Unknown Structures.

The Objective Of This Proposed Work Is To Develop A Reliable Method For Dynamic Characterization And Prediction Of Dynamic Response Of Structures Of Known/Unknown Configurations, By Processing The Free Vibration Data Generated Experimentally From The Ground Vibration Tests (GVT)Of The Prototype Vehicles. The Methodology Would Make Use Of The Measured Dynamic Data In Terms Of Mode Shapes, Natural Frequencies, Modal Damping, Point Impedances Etc.And Generate Modal (Scaled) Stiffness And Inertia Information That Will Be Used For Prediction Of Response Characteristics Of The Prototype Structure . With These Objectives, The Present Work Develops The Mathematical Formulation Of The Method, And Demonstrates Its Reliability By Performing The Experiment On A Simple Cantilever Beam To Determine Its Dynamic Characteristics. Results On Scaled Modal Stiffness And Inertia, Generated Through The Method Using Experimental (GVT) Data Show Excellent Agreement With Those Generated By FE And Analytical Models .It Must Be Noted That A Valid Benchmarking Is Performed With The Condition That The Experimental Procedure Is 'Blind' To The Actual Stiffness And Inertia Distributions As Used In FEM Or Analytical Models . Agreement Of The Predicted Response Of The Structure With That From Direct Experiment And Those From The FE And Analytical Models Indicates That This Method Will Be A Promising Tool To Predict The Dynamic And Aeroelastic Characteristics Of Any Prototype Vehicle In The Future. Once The Reliability Of The Method Is Established,It Can Be Extended To Determine The Dynamic And Aeroelastic Characteristics Of All Aircraft For Which Dynamic Characteristics Are Available From A Ground -; Vibration Test (GVT)

GC-MS ANALYSIS, ANTIOXIDANT AND ANTIBACTERIAL ACTIVITIES OF ETHANOL EXTRACT OF LEAVES OF AEGLE MARMELOS (L.) CORRÊA

The aim of the present study was to evaluate the antioxidant activities of leaves of Aegle marmelos and to identify the bioactive compounds by performing GC-MS analysis resulting in the presence of volatile and semi volatile compounds. The IC50 of DPPH˙ radical scavenging assay was 78.36µg/mL concentration respectively. Also, the IC50 of Phosphomolybdenum reduction and ferric reducing power assay were 41.35 and 20.58µg/mL concentration respectively. Also, total phenolic and flavonoid content were determined, in which flavonoids were found to be predominantly higher. The results of this study portray the effective antioxidant activity of Aegle marmelos and further studies are required to isolate the active compounds from various parts of this species and their mode of action. From the study it can be concluded that the plant might be promising as a curative for many diseases associated with free radicals. Keywords: Free radicals, Aegle marmelos, Antioxidant, Dot plot, DPPH˙ assay, IC50, GCMS

Pharmacological activities of aqueous flower extract of Ixora coccinea L.

Nature has blessed the universe with plenty of medicinal plants, so often referred as the Medicinal Garden of the world. In Indian Vedas, the medicinal plants including every part of the plant from roots to flowers were used for curing several diseases. Therefore, it is necessary to enrich the dietary system with antioxidant molecules to protect the human system against various diseases. The aim of the study was to evaluate antioxidant, anti-inflammatory, antibacterial and antidiabetic activities of aqueous flowers extract of Ixora coccinea belongs to the family Rubiaceae. Antioxidant activities such as DPPH· radical, superoxide (O2.-) radical scavenging activities, phosphomolybdenum reduction and Fe3+ reducing power activities were carried out. The IC50 of DPPH· radical and superoxide (O2.-) radical were 13.58 and 23.51 µg/mL concentrations. The RC50 of phosphomolybednum reduction and Fe3+ reduction were 20.57 and 14.57 µg/mL concentrations. The IC50 of haemolytic inhibition was 99.72 µg/mL concentration. Total phenolic and flavonoid content were 369.1 µg/mg Gallic acid equivalents and 55.14 µg/mg Quercetin equivalents. The IC50 of alpha amylase enzyme inhibition was 655.02 µg/mL concentration. The antibacterial activity showed maximum zone of inhibition of 15mm for B. subtilis at 500 µg/mL concentration. Keywords: Antioxidant, DPPH· radical, Superoxide (O2.-) radical, alpha-amylase, haemolysis

The evolving SARS-CoV-2 epidemic in Africa: Insights from rapidly expanding genomic surveillance

INTRODUCTION Investment in Africa over the past year with regard to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) sequencing has led to a massive increase in the number of sequences, which, to date, exceeds 100,000 sequences generated to track the pandemic on the continent. These sequences have profoundly affected how public health officials in Africa have navigated the COVID-19 pandemic. RATIONALE We demonstrate how the first 100,000 SARS-CoV-2 sequences from Africa have helped monitor the epidemic on the continent, how genomic surveillance expanded over the course of the pandemic, and how we adapted our sequencing methods to deal with an evolving virus. Finally, we also examine how viral lineages have spread across the continent in a phylogeographic framework to gain insights into the underlying temporal and spatial transmission dynamics for several variants of concern (VOCs). RESULTS Our results indicate that the number of countries in Africa that can sequence the virus within their own borders is growing and that this is coupled with a shorter turnaround time from the time of sampling to sequence submission. Ongoing evolution necessitated the continual updating of primer sets, and, as a result, eight primer sets were designed in tandem with viral evolution and used to ensure effective sequencing of the virus. The pandemic unfolded through multiple waves of infection that were each driven by distinct genetic lineages, with B.1-like ancestral strains associated with the first pandemic wave of infections in 2020. Successive waves on the continent were fueled by different VOCs, with Alpha and Beta cocirculating in distinct spatial patterns during the second wave and Delta and Omicron affecting the whole continent during the third and fourth waves, respectively. Phylogeographic reconstruction points toward distinct differences in viral importation and exportation patterns associated with the Alpha, Beta, Delta, and Omicron variants and subvariants, when considering both Africa versus the rest of the world and viral dissemination within the continent. Our epidemiological and phylogenetic inferences therefore underscore the heterogeneous nature of the pandemic on the continent and highlight key insights and challenges, for instance, recognizing the limitations of low testing proportions. We also highlight the early warning capacity that genomic surveillance in Africa has had for the rest of the world with the detection of new lineages and variants, the most recent being the characterization of various Omicron subvariants. CONCLUSION Sustained investment for diagnostics and genomic surveillance in Africa is needed as the virus continues to evolve. This is important not only to help combat SARS-CoV-2 on the continent but also because it can be used as a platform to help address the many emerging and reemerging infectious disease threats in Africa. In particular, capacity building for local sequencing within countries or within the continent should be prioritized because this is generally associated with shorter turnaround times, providing the most benefit to local public health authorities tasked with pandemic response and mitigation and allowing for the fastest reaction to localized outbreaks. These investments are crucial for pandemic preparedness and response and will serve the health of the continent well into the 21st century

Tuning of Mechanical Vibration Absorber for seaking Helicopter

The report deals with the procedure, test method and test details for the tuning of mechanical absorbers housing the battery of Seaking Helicopter. The approach recommended, by the Sikorsky Aircraft Co., vide their report No. ATP '23,004 is adopted

Ground Resonance Test and Response analysis of HS 748 aircraft a Preliminary report

The report deals with the preliminary results obtainer from the ground resonance test and response analysis of I1S 74" Aircraft. Comparisons of wing natural frequencies obtained from different excitations have: been made. Modal analysis results the wing are also enclosed . Recommendation for further tests the present and modified configurations of the aircraft have been include

Phytochemical Analysis, Antioxidant Activities and GC-MS Profiling of Ethanol Bract Extract of Musa paradisiaca L.

In recent year’s trend towards authentication, standardization and quality assurance of selected medicinal plants has been rapid increase for potential therapeutic significance. Despite the modern techniques, identification of plant drug by pharmacognostic study is more reliable. In Ayurveda, a traditional system of medicine Musa Paradisiaca is commonly used in Asthma, Diabetes, Anthelmintic, Hypertension, Insomnia, Snake bite. The whole plant as well as specific parts (leaves, ripe and unripe fruits, stems) of plant extract and its active constituents have been used for the treatment of large number of human ailments. Phytochemicals are virtually present in all the fruits, vegetables, pulses/legumes and grains which are commonly consumed, so it is quite easy to incorporate them in our daily diet. Current research studies were carried out for evaluating the antioxidant activities of ethanol bract extract of Musa paradisiaca. Antioxidant activities such as DPPH˙ radical, Superoxide (O2.-) radical, Nitric Oxide (NO) radical, ABTS●+ radical cation, phosphomolybdenum reduction and Fe3+ reduction were carried out for ethanol bract extract of Musa paradisiaca. The maximum DPPH˙ radical, Superoxide (O2.-) radical and Nitric Oxide (NO) radical scavenging activities were 52.05±0.38%, 57.71±0.45% and 49.63±0.32% at 120 µg/mL concentration and the IC50 values were 68.47 µg/mL, 71.37 µg/mL and 93.94 µg/mL concentrations respectively. The maximum ABTS●+ radical cation scavenging activity was 84.28±0.13% at 30 µg/mL concentration and the IC50 value was 10.04 µg/mL concentration respectively. The maximum Mo6+ reduction and Fe3+ reduction were 45.38±0.40% and 57.06±0.32% at 120 µg/mL concentration and the RC50 values were 121.44 µg/mL and 85.43 µg/mL concentrations respectively. Z-2-Tridecen-1-ol, Nonadecane-2,4-dione, a-Ketostearic acid, 2,5-Furandione, dihydro-3-(2-tetradecenyl)- were found to be the potent antioxidant compounds detected from GC-MS analysis. Keywords: Antioxidant, phenolic compounds, Nitric Oxide (NO) radical, ABTS●+ radical cation, Fe3+ reduction and a-Ketostearic acid

Analysis of Semen Parameters with Age of Infertile Male Subjects-A Pilot Study in an Urban Population Chennai

ABSTRACT Infertility is a growing medical and social problem and 30-40% of it is attributed to male factor. As the quality of semen is a valuable indicator of male reproductive health, the purpose of this study is to focus on age related changes in semen parameters in men with infertility.The study was performed in men attending the infertility clinic of Sree Balaji Medical college and Hospital and Prashanth fertility centre of Chennai.The association of age with semen parameters like volume, concentration, motility was evaluated according to WHO criteria. Correlation and linear regression model were used to examine the relationship.The mean value of semen volume was 2.42 ml and semen concentration was 49.8 ×10 6 per ml . The mean value for fast progressive motility was 17% and 21.43 % for slow progressive motility and 38.43% for total motility. In 50% of infertile men, the total motility value was below the threshold level according to WHO criteria 2010. Except volume and concentration other parameters like fast progressive motility, slow progressive motility and total motility showed significant negative correlation with age.Fifty percentage of infertile males do not fulfill the WHO threshold value of total motility

Identification of Newer Stable Genetic Sources for High Grain Number per Panicle and Understanding the Gene Action for Important Panicle Traits in Rice

Rice is an important food crop extensively cultivated worldwide, and rice’s grain yield should be improved to meet future food demand. Grain number per panicle is the main trait that determines the grain yield in rice, and other panicle-related traits influence the grain number. To study the genetic diversity, 50 diverse Indian-origin germplasm were evaluated for grain number per panicle and other panicle traits for two consecutive seasons (Rabi 2019 and Kharif 2020). The maximum genotypic and phenotypic coefficient of variation was obtained for the number of spikelets and filled grains per panicle. The genotypes were grouped into eight clusters with Mahalanobis’ D2 analysis and six groups using Principal component analysis. Based on, per se, performance for grain number per panicle and genetic distances, six parents were selected and subjected to full diallel mating. The genotypes CB12132, IET 28749, and BPT 5204 were the best general combiners for the number of filled grains per panicle and other panicle branching traits, viz., the number of primary and secondary branches per panicle. The hybrid BPT 5204 × CB 12132 identified as the best specific combination for most of the studied panicle traits. The additive gene effects were high for the number of filled grains per panicle, the number of primary branches, and secondary branches, whereas non-additive gene action was high for the number of productive tillers and grain yield per plant. The information obtained from this study will be useful in rice breeding programs to improve panicle traits, especially the grain number, which would result in higher grain yield