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Fixation plates are crucial to ensure the fracture site remains stable and prevent any movement that could widen the gap between broken bones, ultimately promoting the healing process of the bone. Topological optimization is a solution to increase the strength-to-mass ratio and produce lightweight metal implants with less stiffness to reduce stress shielding. Laser-Directed Energy Deposition (L-DED) is a 3d printing method to fabricate objects with near-net shapes. However, the manufactured implants' surface quality is still a major issue and further leads to an increase in the release of metal ions, which can cause inflammation and infection and lead to screw loosening. The current study aims to design and develop the topologically optimized fixation plate to reduce stress shielding further fabricated and polished by the L-DED and H-ECMR super polishing method, respectively. Herein, the H-ECMR super finishing method reduced the Ra value of the manufactured parts to 29.26 nm. [ABSTRACT FROM AUTHOR]

Hybrid Chemo-Magnetorheological Finishing (HC-MRF) process is an advanced surface finishing process that utilizes the interaction of Magnetorheological Finishing and chemical etching to reduce the surface roughness of the cemented carbide cutting tools. Herein, Murakami's reagent is used as a Magnetorheological (MR) fluid carrier medium to trigger chemical etching and mechanical abrasion. The synergic action reduces surface finishing time and increases process efficiency. However, optimizing process parameters during the HC-MRF process is required to improve process efficiency further. Response Surface Methodology (RSM) is used to develop the regression model to study the impact of process parameters (i.e. spindle speed, feed rate, and vol.% of Murakami's reagent in MR fluid) on the surface quality. Three surface roughness parameters, namely average surface roughness (Ra), skewness (Rsk), and kurtosis (Rk), are opted to analyze the surface characteristics of the polished surface. Furthermore, optimization is performed with the help of a Genetic Algorithm (GA) to achieve the best surface quality following input parameters. The surface roughness (Ra) is reduced by 88.97% as the initial Ra value decreases to 34.50 nm from 312.87 nm after the HC-MRF process. The results obtained from RSM and GA are in good agreement with the experimental results. The optimum value of feed rate, spindle speed, and vol.% of Murakami's reagent in the MR fluid while achieving minimum surface roughness value (i.e. 31.26 nm) through GA are 1.2 mm/min, 23 rpm, and 53%, respectively. The measured kurtosis (Rku) value of 0.64 at the optimum process parameter condition represents flat peaks on the surface roughness irregularities of the polished surface. Similarly, a skewness (Rsk) value of 1.46 signifies that the number of peaks is higher than the number of valleys on the polished surface. Furthermore, it is observed that the Vol.% of Murakami's reagent in MR fluid is the most significant process parameter compared with other parameters among all responses. [ABSTRACT FROM AUTHOR]

Sexed semen facilitates additional female calf production for the expansion of a herd at a faster rate and also curtails the surplus production of unwanted male calves. A study was conducted to evaluate the performance of sexed semen in indigenous Tharparkar cows based on 114 artificial inseminations (AI) performed at natural oestrus using two protocols i.e., single AI (n = 48) and double AI (n = 66). Overall, the first service conception rate (CR) was significantly higher in double (53.0%) than single (33.3%) AI protocol. The odds ratio of conception rate in double AI was 2.26 (χ2 = 4.4, df = 1, p =.04) with respect to single AI. The time that elapsed since the detection of oestrus to insemination was also analysed. In a single AI protocol, the CR was higher (p <.05) at 16 h (54.6%) than insemination at 8 h (27.0%) following the onset of oestrus. Yet, the CR using double AI protocol did not differ (p =.73) significantly when AIs were performed either at 8 h and 24 h (51.9%) or 16 h and 24 h (57.1%) post onset of oestrus. Besides, like the single AI protocol, the parity of the animals also influenced the CR, being higher in heifers (n = 22) than those of parous (n = 92) cows (72.73 vs. 40.43%, χ2 = 7.48, df = 1, p =.006) in the present study. The odds ratio of conception in heifers was 3.93 with respect to parous cows. Overall, the birth of female calf was 91.7%. In conclusion, the present study indicates a future promise of the sexed semen for the production of more female offspring from Tharparkar cattle. [ABSTRACT FROM AUTHOR]

Nowadays, Additive Manufacturing (AM), i.e., the 3D Printing process, is one of the advanced manufacturing processes for making a complex geometry with high accuracy. Additive manufacturing processes are widely used worldwide and are the fastest-growing industrial technology, as any complex structure with minimal wastage of materials can be fabricated. However, poor surface quality is a major limitation of additive manufacturing due to surface defects, including unmelted powder particles, balling, porosity, etc. Laser polishing utilizes remelting and reflowing of the surface irregularities under the influence of a high-power laser source to efficiently improve the surface quality of the additively manufactured parts. Herein, a thin layer of the surface is molten, and because of surface tension, molten material flows from the peak into the valley with no loss of material from the surface. Laser polishing is a CNC-operated surface finishing method, hence an appropriate toolpath strategy is required to produce uniform surface quality on the polished surface. In the present work, the impact of various toolpath strategies, i.e., raster, offset flat, contour parallel, Hilbert, Peano, and spiral, over the final surface quality is analyzed during the laser polishing. The maximum 92% reduction in average surface roughness with uniform surface quality is observed with a fractal-based toolpath strategy, i.e., Peano with improved surface hardness. Moreover, laser polishing is capable of reducing all surface defects from the fabricated surface, as observed from the scanning electron microscope. Furthermore, an insignificant change in the surface composition of the material is observed after the laser polishing. [ABSTRACT FROM AUTHOR]

Background: Human immunodeficiency virus infection leads to a variety of Cardiovascular manifestations. Pericardial effusion, systemic hypertension, dilated cardiomyopathy, coronary artery disease, pulmonary hypertension, primary as well as secondary cardiac tumours etc are seen in about 30% of patients with Human Immunodeficiency Virus infection and the incidence has increased with improved longevity. Coronary artery disease ranging from subclinical atherosclerosis to coronary plaque rupture causing acute coronary syndrome have been documented. The main underlying pathophysiological process is a state of perennial inflammation which leads to initiation and acceleration of coronary atherosclerosis. To study the coronary angiographic Objective : profile in HIV patients. HIV patients undergoing Methodology : coronary angiography were assessed clinically, biochemically and finally by coronary angiography to see the coronary pathoanatomy. Results : Of the 37 HIV patients studied between Jan to Dec 2019, the mean age was 47 years.(19-66 years).Two thirds were males and the most common traditional risk factor was dyslipidemia followed by hypertension. Majority of patients were already on ART and the CD 4 counts ranged from 67-366 cells/cumm. Anterior wall MI and unstable angina were the most common clinical presentations. Coronary angiography revealed diffuse disease (both insignificant and significant) of the left anterior descending artery as the most common pattern of angiographic involvement. Conclusion : Coronary artery disease both subclinical and syndromic occurs with increased frequency in HIV patients. The dominant angiographic presentation correlates with the clinical presentation and in our study, left anterior descending artery was more frequently diseased as compared to other coronary vessels. The most common angiographic pattern consistent with coronaries was the presence of ectasia and diffuse disease. [ABSTRACT FROM AUTHOR]