Marxist thought in Tamil Novels

Marxism, which produced the theory of communism, is very extensive. This field that originated in the West and grew up in Tamil novel literature, and Karl Marx and Friedrich Engels are the founders of Marxism, which has the principle of equality for the working class. The theory of reflection is the theory that is primarily in the literary theories advanced by Marxism. That is, the class conflicts in society cause crises in human lives. The economic inequality in society is the primary cause of social contradiction. Struggles erupt when the bourgeoisie exploits the working people. This article seeks to examine the struggles in Tamil novels published in the 21st century

FABRICATION AND TESTING OF ALUMINIUM (Al 7075) WITH DIFFERENT COMPOSITION OF SiC & FLY ASH

Al7075 is used in automobile industries because of its lower weight to strength ratio. Aluminium metal matrix composites (AMCs) are the competent material in the industrial world due to its excellent mechanical properties. Powder metallurgy processing is the one of the most effective methods for manufacturing the composites with high volume of reinforcement. The present study is dealt with the hybrid composites (Al7075+SiC+Fly ash) through powder metallurgy technique. This hybrid composite having with various weight percentages of SiC& Fly ash particles morphology can be seen with the help of micro structural examine. The mechanical properties such as Hardness, Impact strength, micro structure were studied and reported with the increase in weight percentage of SiC & Fly ash in the Aluminium metal Matrix. Aluminium hybrid composites are a new generation of metal matrix composites that have the potential of satisfying the recent demands of advanced engineering applications. The major techniques for fabricating these materials are briefly discussed and research areas for further improvement on Aluminium hybrid composites are suggested

A study on the development of scaffold fabrication using citric acid polyester – nanohydroxyapatite composite

ABSTRACT. Nano hydroxyapatite (n-HAp) and its composites have shown a great development in the field of tissue regeneration and in controlled drug delivery due to its good biocompatibility and bioactivity behavior. Furthermore, HAp-based nanocomposites enhance mechanical properties. These synthetic HAp nanocomposites can also be tailored to fabricate scaffold with controlled porosity which facilitate the growth of the cell in the field of tissue engineering. In this paper, we focus on the synthesis of nano hydroxyapatite (n-HAp) by sol-gel method. The synthesized nano powders were calcined at 500 oC and characterized by FT-IR, XRD and TEM. We have also described the synthesis of citric acid-based polyester by melt polycondensation method without adding catalyst. The monomers used were citric acid, 1,6-hexane diol and sebacic acid. The corresponding synthesized n-HAp/polyester composite have potential application in soft tissue engineering. The structures of polyester and its nanocomposite were studied by FT-IR and 1H NMR spectral studies. The thermal and mechanical properties of polyester, composites and cytotoxicity activity (MTT assay) using vero cells were also studied. Porous scaffold of the nano HAp/Polyester was fabricated by solvent-casting particulate leaching technique which is useful in the development of tissue engineering applications. SEM and TEM studies were carried out for nano HAp, polyester, composites and scaffold.   KEY WORDS: Cytotoxicity, Polycondensation, Sol-gel, Solvent-casting, Tissue engineering Bull. Chem. Soc. Ethiop. 2022, 36(4), 923-934.                                                                DOI: https://dx.doi.org/10.4314/bcse.v36i4.17                                                     &nbsp

Investigations on structural, optical, and impedance spectroscopy studies of titanium dioxide nanoparticles

This article explains a novel synthesis for producing titanium dioxide (TiO2) nanoparticles by a sol-gel technique using titanium tetraisopropoxide as a titanium source. The synthesized nanoparticles were analyzed using many measurements like X-ray diffraction (XRD), HRTEM, absorption UV spectroscopy, FTIR, and ac impedance spectroscopy. X-ray peaks were used to calculate the crystallite size and lattice strain by Williamson–Hall method. Crystallite size calculated from x-ray diffraction using the Scherrer equation gives an approximate size and cannot be used for measurements. TiO2 nanoparticles are found to possess a tetragonal structure with a crystalline size around 12 nm. Particle size was confirmed by HRTEM images. The optical studies response for the nanoparticles showed the possible visible absorption peaks for TiO2 nanoparticles are 323 nm. Bandgap energy (Eg) of the TiO2 nanoparticle calculated from UV visible absorption spectra is discussed, and the bandgap is 3.14 eV. FTIR spectra showed vibration bands of the Ti-O network. AC Conductivity properties of TiO2 nanoparticles are studied in the frequency range 1 to 8 MHz at varying temperatures. The conductivity of the TiO2 nanoparticle is found to be constant in the low angular frequency region. Dielectric parameters were analyzed at different temperatures and frequencies.                     KEY WORDS: Conductivity, Dielectric, Nanoparticles, Titanium dioxide, Structural studies   Bull. Chem. Soc. Ethiop. 2021, 35(1), 151-160. DOI: https://dx.doi.org/10.4314/bcse.v35i1.1

A successful full term delivery in a case of robotic assisted insertion of transabdominal cerclage in an obese woman with multiple uterine fibroids

Cervical incompetence is not an uncommon presentation in an obstetric emergency unit. Some of these patients will be managed with a cervical cerclage. While the management of patients presenting with first time cervical incompetence is relatively established, the management of patient with repeated cervical incompetence might require an abdominal cerclage. Abdominal cerclages can be inserted traditionally via laparotomy or via a minimally invasive approach (MIS). We present a case of an obese patient presenting with 3 previous second trimester miscarriages despite 2 cervical cerclage complicated by multiple uterine fibroids who underwent a robotic assisted insertion of transabdominal cerclage (RTAC) pre-pregnancy. She subsequently conceived spontaneously and carried the pregnancy to term and delivered a healthy baby via caesarean section. There have been multiple published studies showing that an MIS approach for abdominal cerclage insertion is safe and viable. Robotic assisted procedures allow for better visualisation and manipulation of tissue especially in patients anticipating a complex procedure. For our patient we feel that a robotic assisted procedure would be more beneficial given her profile and the complexity of her case

A Study on Anterior Decompression and Stabilisation of Dorsolumbar Spine Burst Fractures and Caries Spine

INTRODUCTION: Spine is one of the intriguing regions in Orthopeadics where treatment for its pathology has drawn much controversy. Before the dawn of 20th century spine injuries were treated non-operatively. Later Harrington revolutionized spine care and rehabilitation with introduction of posterior instrumentation. Since then surgical techniques and instruments have proliferated to improve anatomical reduction and alignment of spinal column. But neurological recovery remained mostly unchanged over the results of non operative treatment. However root function and spinal cord function , in selected patients can be improved with appropriate surgery. Dorsolumbar region constitutes the second most common site for spine fractures and burst fractures constitute 60% of dorsolumbar fractures. Though the treatment of burst fractures associated with neurological injury is controversial, many investigators have reported favourable results with anterior decompression and stabilization surgery. The other major pathology of spine for which anterior decompression and stabilization surgery is favoured at present is Caries spine. AIM: To evaluate the effectiveness of anterior decompression and stabilisazion of dorsolumbar spine in terms of 1. Neurological recovery, 2. Kyphotic angle correction, 3. Bone graft fusion, 4. Pain scale of denis, and 5. Work scale of denis. MATERIALS AND METHODS: Twenty two patients who were operated with anterior decompression and stabilization of thoracolumbar spine pathology in Govt. General Hospital, Chennai with follow up of minimum six months were included in the study. Among those operated with anterior decompression and stabilization, Dorsolumbar burst fractures - 12 cases, Caries spine - 10 cases. The interval from injury to surgery was an average 18 days in burst fracture pts. The average duration of caries spine with which they presented to us was 3.2 months. Inclusion Criteria- We included cases of burst fracture affecting dorsal and lumbar vertebrae presenting with neurologic deficit and canal compromise >50%. Tuberculous spondylitis affecting dorsal and lumbar vertebra are also included. The indication for surgery were neurologic deficit, vertebral body destruction with significant angulation with or without cold abscess. All caries spine patients took ATT for a minimum period of 6 months. Exclusion Criteria - Patients with no neurologic deficit and those with severe medical comorbidities were excluded from the study. RESULTS: All the patients included in the study had preoperative neurologic deficits. In trauma spine, out of 12 cases, 5 cases, (41.6%) with incomplete spinal cord, injury improved to Frankel grade D/E neurology (walking with/without support). Out of 5 cases, one case had injury at D-12 level other had injury below L1 level. 7 cases (58.3%) with complete spinal cord injury remained the same at follow up. CONCLUSION: Anterior decompression and stablisation with anterior instrumentation with single rod system, - definitely improves neurology in incomplete spinal cord injury patients and most of caries spine patients. - though the kyphotic correction achieved is low, functionally (pain & work scale wise) patient has little difficulty

Probing the anticancer mechanism of prospective herbal drug Withaferin A on mammals: a case study on human and bovine proteasomes

<p>Abstract</p> <p>Background</p> <p>The UPP (ubiquitin proteasome pathway) is the major proteolytic system in the cytosol and nucleus of all eukaryotic cells which regulates cellular events, including mitotis, differentiation, signal transduction, apoptosis, and inflammation. UPP controls activation of the transcriptional factor NF-κB (nuclear factor κB), which is a regulatory protein playing central role in a variety of cellular processes including immune and inflammatory responses, apoptosis, and cellular proliferation. Since the primary interaction of proteasomes occurs with endogenous proteins, the signalling action of transcription factor NF-κB can be blocked by inhibition of proteasomes. A great variety of natural and synthetic chemical compounds classified as peptide aldehydes, peptide boronates, nonpeptide inhibitors, peptide vinyl sulfones and epoxyketones are now widely used as research tools for probing their potential to inhibit proteolytic activities of different proteasomes and to investigate the underlying inhibition mechanisms. The present work reports a bio-computational study carried out with the aim of exploring the proteasome inhibition capability of WA (withaferin A), a steroidal lactone, by understanding the binding mode of WA as a ligand into the mammalian proteasomes (X-ray crystal structure of <it>Bos taurus</it> 20S proteasome and multiple template homology modelled structure of 20S proteasome of <it>Homo sapiens</it>) using molecular docking and molecular dynamics simulation studies.</p> <p>Results</p> <p>One possible mode of action which is proposed here for WA to act as a proteasome inhibitor is by suppression of the proteolytic activity which depends on the N-terminal threonine (Thr1) residue hydroxyl group. Docking studies carried out with herbal ligand WA into the structures of bovine and human proteasomes substantiate that WA has the ability to inhibit activity of mammalian 20S proteasomes by blocking the nucleophilic function of N-terminal Thr1. Results from molecular dynamics simulations in water show that the trajectories of both the native human 20S proteasome and the proteasome complexed with WA are stable over a considerably long time period of 4 ns suggesting the dynamic structural stability of human 20S proteasome/WA complex.</p> <p>Conclusions</p> <p>Inhibition of proteasomal activity are promising ways to retard or block degradation of specific proteins to correct diverse pathologies. Though quite a number of selective and efficient proteasomal inhibitors exist nowadays, their toxic side effects limit their potential in possible disease treatment. Thus there is an indispensable need for exploration of novel natural products as antitumor drug candidates. The present work supports the mammalian proteasomes inhibiting activity of WA along with elucidation of its possible mode of action. Since WA is a small herbal molecule, it is expected to provide one of the modest modes of inhibition along with added favours of ease in oral administration and decreased immunogenicity. The molecular docking results suggest that WA can inhibit the mammalian proteasomes irreversibly and with a high rate through acylation of the N-terminal Thr1 of the β-5 subunit.</p