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The impact of left ventricular dysfunction on clinical outcomes following revascularization is not well established in patients with unprotected left main coronary artery disease (ULMCA). In this study, we evaluated the impact of left ventricular ejection fraction (LVEF) on clinical outcomes of patients with ULMCA requiring revascularization with percutaneous coronary intervention (PCI) compared with coronary artery bypass graft (CABG).The details of the design, methods, end points, and relevant definitions are outlined in the Gulf Left Main Registry: a retrospective, observational study conducted between January 2015 and December 2019 across 14 centres in 3 Gulf countries. In this study, the data on patients with ULMCA who underwent revascularization through PCI or CABG were stratified by LVEF into three main subgroups; low (l-LVEF40%), mid-range (m-LVEF 40-49%), and preserved (p-LVEF ≥50%). Primary outcomes were hospital major adverse cardiovascular and cerebrovascular events (MACCE) and mortality and follow-up MACCE and mortality.A total of 2137 patients were included; 1221 underwent PCI and 916 had CABG. During hospitalization, MACCE was significantly higher in patients with l-LVEF [(10.10%), P = 0.005] and m-LVEF [(10.80%), P = 0.009], whereas total mortality was higher in patients with m-LVEF [(7.40%), P = 0.009] and p-LVEF [(7.10%), P = 0.045] who underwent CABG. There was no mortality difference between groups in patients with l-LVEF. At a median follow-up of 15 months, there was no difference in MACCE and total mortality between patients who underwent CABG or PCI with p-LVEF and m-LVEF.CABG was associated with higher in-hospital events. Hospital mortality in patients with l-LVEF was comparable between CABG and PCI. At 15 months' follow-up, PCI could have an advantage in decreasing MACCE in patients with l-LVEF.

Introduction: Evaluate the effects of baseline anemia and anemia following revascularization on outcomes in patients with Unprotected Left Main Coronary Artery (ULMCA) disease. Methods: This was a retrospective, multicenter, observational study conducted between January 2015 to December 2019. The data on patients with ULMCA who underwent revascularization through PCI or CABG was stratified by hemoglobin level at baseline into anemic and non-anemic groups to compare in-hospital events. The pre-discharge hemoglobin following revascularization was categorized into very low (

Medium-frequency (mid-frequency) vibration analysis of complex structures plays a prominent role in automotive, aerospace, mechanical, and civil engineering. Flexible beam structures displayed by the traditional Euler–Bernoulli pillar hypothesis have been broadly utilized in different designing issues. A kinematic speculation made in the Euler–Bernoulli shaft hypothesis is that the plane areas of a pillar typical to its impartial pivot remain planes after the bar encounters twisting disfigurement, which ignores shear deformity. The expanded DTFM decides the recurrence reaction of a bar structure in a careful and insightful structure, in any recurrence locale covering low, center, or high frequencies. In the mean time, the proposed technique gives the nearby data of a bar structure, like uprooting, shear misshapening, bowing second and shear power at any area, which in any case would be extremely challenging with energy-based strategies. amplifiers by and large accept that a confined main thrust can spread energy uniformly across the outside of a board. Notwithstanding, examinations have shown that board vibrations stay confined around the driving point at high frequencies, Energy spreading will possibly happen when the board is incited in a recurrence district with a low thickness of modes, as numerous modes impelled together will join to frame a band-restricted delta work at the area of the main impetus. A quantitative proportion of limitation is presented, in light of the proportion of the energy contained in a little locale around the driving point to the energy contained in the whole board. Analyses show that the limitation transcends a basic recurrence, and this basic recurrence connects well with forecasts of the great recurrence plate district utilizing standard modular cross-over measurements.

Increase in energy requirement has lead to the development of new energy storage devices for the movement of vehicles. This paper categorises the various types of vehicles with different intensities of hybrids based on degree of hybridisation. The parameters which depend on the performance of the battery are shallow cycle life, high dynamic charge acceptance for sturdy for regenerative braking and sturdy life of the battery. Lead Acid battery either liquid or absorptive glass fibre is expected to work with 14 V systems for micro hybrids with low cost battery maintenance system for increasing applications.. Advanced latest batteries are considered for mild or medium hybrid once they have proven the worthiness under real operating conditions under dynamic responses. NiMH and Li-ion batteries are dominating current and potential battery for high functionality HEVs. Li -ion offers an attractive opportunity for improvement in performance and cost. Super capacitors are considered for power applications where in the variation of signal is in the pulse form. Specific attention is given to system integration of the battery and advance technology during vehicle integration. In this paper there are various opportunities and challenges in obtaining a potential battery pack.

Background: We report a 25-year-old male who presented to an outside institution with progressive dyspnoea. He had increased jugular venous pressure and muffled heart sounds, suggesting a pericardial tamponade. A diagnosis of a cardiac angiosarcoma was put forward. Primary cardiac tumours are rare, and patients can present with constitutional symptoms, posing a diagnostic challenge. The objective of this report is to suggest a diagnostic standard for early recognition of these fatal tumours. Case presentation: A chest radiograph demonstrated an enlarged cardiac contour and signs of pericardial tamponade. Pericardiocentesis was performed, complicated by a pneumopericardium and the pericardial fluid was haemorrhagic and exudative. Echocardiography confirmed a right atrial mass featured by heterogeneous enhancement in subsequent chest computed tomography and magnetic resonance imaging concerning a sarcoma. No metastatic lesions were found. The tumour was excised completely, and the following echocardiogram indicated normokinetic biventricular function. Histological examination of the tumour cells confirmed the presence of a cardiac angiosarcoma. Patient was scheduled for combined chemotherapy following discharge. Conclusion: Primary cardiac angiosarcomas are difficult to diagnose due to the rarity of the tumour as well as the non-specific symptoms. An early diagnosis may help improve prognosis which emphasizes the importance of establishing a standard diagnostic protocol for such tumours.

Real-world data for managing patients with diabetes and left main coronary artery (LMCA) disease are scarce. We compared percutaneous coronary intervention (PCI) outcomes versus coronary artery bypass grafting (CABG) in diabetes and LMCA disease patients.We retrospectively studied patients with LMCA presented to 14 centers from 2015 to 2019. The study included 2138 patients with unprotected LMCA disease; 1468 (68.7 %) had diabetes. Patients were grouped into; diabetes with PCI (n = 804) or CABG (n = 664) and non-diabetes with PCI (n = 418) or CABG (n = 252).In diabetes, cardiac (34 (5.1 %) vs. 22 (2.7 %); P = 0.016), non-cardiac (13 (2 %) vs. 6 (0.7 %); P = 0.027) and total hospital mortality (47 (7.1 %) vs. 28 (3.5 %); P = 0.0019), myocardial infarction (45 (6.8 %) vs. 11 (1.4 %); P = 0.001), cerebrovascular events (25 (3.8 %) vs. 12 (1.5 %); P = 0.005) and minor bleeding (65 (9.8 %) vs. 50 (6.2 %); P = 0.006) were significantly higher in CABG patients compared to PCI; respectively. The median follow-up time was 20 (10-37) months. In diabetes, total mortality was higher in CABG (P = 0.001) while congestive heart failure was higher in PCI (P = 0.001). There were no differences in major adverse cerebrovascular events and target lesion revascularization between PCI and CABG. Predictors of mortality in diabetes were high anatomical SYNTAX, peripheral arterial disease, chronic kidney disease, and cardiogenic shock.In this multicenter retrospective study, we found no significant difference in clinical outcomes during the short-term follow-up between PCI with second-generation DES and CABG except for lower total mortality and a higher rate of congestive heart failure in PCI group of patients. Randomized trials to characterize patients who could benefit from each treatment option are needed.

The industrial applications of composite materials have significantly increased during the past few years. This trend is mainly due to the fact that composite materials have excellent properties, which are very different from conventional isotropic materials. Composite materials have high strength-weight, high stiffness-weight ratio and are corrosion resistant, thermally stable and are well suited for structures in which the weight is a fundamental variable in the design process. It has been found from experiments that there is no immediate effect of spray paint on the resin system of the CFRP material as there is no variation with Material Property between tested coupons without paint and tested coupons with paint. It is concluded that Digital Image Correlation Technique (DIC) a viable and feasible technique of whole field strain measurements on the composite materials.

Robots are extensively used in industries for their precision work and amount of work that one can obtain without any defects. In this paper we are using a gantry robot for as it does not occupy the floor space therefore reducing the distance for reachability of the parts and hence reducing unnecessary material for guide way. Robots work in strictly defined path and there is no or very little change in such systems in order to overcome this we are using a vision based control system to make the system dynamic in nature the images are picked by using a USB camera processed images of the object is transmitted via serial communication to the Arduino Mega 2560 microcontroller and processed using pythons open source computer vision (Open CV) image to process the image captured by the USB camera to find the exact colour and to pick the object and sort it.

Foil bearings are used in extremely high elevated temperature and at high speed. Implementation of this kind of bearing lies in selecting a suitable lubricant whether a solid or liquid lubricant. The main view of selecting this topic is to study the various extreme conditions of using a lubricant for different chemical conditions and physical conditions such as surface morphology and geometric features of the bearing. In order to evaluate the tribological properties the tests were done at high temperature using Anton Par tribometers. We implemented Inconel test substrate and coatings of different thickness varying from 0.2 μm.to 0.5 μm. The bearing sample was tested at the higher elevated temperature and around 600 cycles of fatigue loading was applied at a temperature of 900 °C the obtained stress was around 14.5 KPa. These results were very good and the application of this bearing was seen in the gas power cycle of aero planes.

Currently, gender is not considered in the choice of the revascularization strategy for patients with unprotected left main coronary artery (ULMCA) disease. This study analyzed the effect of gender on the outcomes of percutaneous coronary intervention (PCI) vs coronary artery bypass grafting (CABG) in patients with ULMCA disease. Females who had PCI (n = 328) were compared with females who had CABG (n = 132) and PCI in males (n = 894) was compared with CABG (n = 784). Females with CABG had higher overall hospital mortality and major adverse cardiovascular events (MACE) than females with PCI. Male patients with CABG had higher MACE; however, mortality did not differ between males with CABG vs PCI. In female patients, follow-up mortality was significantly higher in CABG patients, and target lesion revascularization was higher in patients with PCI. Male patients had no difference in mortality and MACE between groups; however, MI was higher with CABG, and congestive heart failure was higher with PCI. In conclusion, women with ULMCA disease treated with PCI could have better survival with lower MACE compared with CABG. These differences were not evident in males treated with either CABG or PCI. PCI could be the preferred revascularization strategy in women with ULMCA disease.

Coronary artery bypass grafting (CABG) and percutaneous coronary intervention (PCI) in revascularization of left main coronary artery (LMCA) disease has been evaluated in previous studies. However, there has been minimal study of the relationship between co-existing non-coronary atherosclerosis (NCA) and LMCA disease revascularization. We aim to examine this relationship. The Gulf-LM study is a retrospective analysis of unprotected LMCA revascularization cases undergoing PCI with second generation drug-eluting stent vs CABG across 14 centers within 3 Gulf countries between January 2015 and December 2019. A total of 2138 patients were included, 381 with coexisting NCA and 1757 without. Outcomes examined included major adverse cardiovascular and cerebrovascular events (MACCE), cardiac and non-cardiac death, and all bleeding. In patients with NCA, preexisting myocardial infarction and congestive heart failure were more common, with PCI being the most common revascularization strategy. A statistically significant reduction in in-hospital MACCE and all bleeding was noted in patients with NCA undergoing PCI as compared to CABG. At a median follow-up of 15 months, MACCE and major bleeding outcomes continued to favor the PCI group, though no such difference was identified between revascularization strategies in patients without NCA.In this multicenter retrospective study of patients with and without NCA who require revascularization (PCI and CABG) for unprotected LMCA disease, PCI demonstrated a better clinical outcome in MACCE both in-hospital and during the short-term follow-up in patients with NCA. However, no such difference was observed in patients without NCA.

Indentation is perhaps the most commonly applied means of testing the mechanical properties of materials. In a traditional indentation test (macro or micro indentation), a hard tip whose mechanical properties are known (frequently made of a very hard material like diamond) is pressed into a sample whose properties are unknown. The load placed on the indenter tip is increased as the tip penetrates further into the specimen and soon reaches a user-defined value. This paper presents the analysis and testing of diaphragm spring used in the Micro Depth Sensing Indenting Machine developed at Indian Institute of Science, Bangalore. Deflection of the spring are found out for various loads using ANSYS and results are validated through physical testing. Modal analysis of spring is carried out to find the possibility of resonance.

Coronary artery bypass surgery (CABG) has been the standard of care for revascularization for patients with obstructive unprotected left main coronary disease (ULMCA). There have been multiple randomized and registry data demonstrating the technical and clinical efficacy of PCI in certain patients with ULMCA. The purpose of this study is to evaluate clinical outcomes of ULMCA PCI as compared to CABG in patients requiring revascularization in three Gulf countries. All ULMCA cases treated by PCI with DES versus CABG were retrospectively identified from 14 centers in 3 Arab Gulf countries (KSA, UAE, and Bahrain) from January 2015 to December 2019. In total, 2138 patients were included: 1222 were treated with PCI versus 916 with CABG. Patients undergoing PCI were older, and had higher comorbidities and mean European System for Cardiac Operative Risk Evaluation (EuroSCORE). Aborted cardiac arrest and cardiogenic shock were reported more in the PCI group at hospital presentation. In addition, lower ejection fractions were reported in the PCI group. In hospital mortality and major adverse cardiovascular and cerebrovascular events (MACCE) occurred more in patients undergoing CABG than PCI. At median follow-up of 15 months (interquartile range, 30), no difference was observed in freedom from revascularization, MACCE, or total mortality between those treated with PCI and CABG. While findings are similar to Western data registries, continued follow-up will be needed to ascertain whether this pattern continues into latter years.

The optimal stenting strategy for unprotected left main coronary artery (ULMCA) disease remains debated. This retrospective observational study (Gulf Left Main Registry) analyzed the outcomes of 1 vs 2 stents in patients with unprotected left main percutaneous coronary intervention (PCI). Overall, 1222 patients were evaluated; 173 had 1 stent and 1049 had 2 stents. The 2-stent group was older with more comorbidities, higher mean SYNTAX scores, and more distal bifurcation lesions. In the 1-stent group, in-hospital events were significant for major bleeding, and better mean creatinine clearance. At median follow-up of 20 months, the 1-stent group was more likely to have target lesion revascularization (TLR). Total mortality was numerically lower in the 1-stent group (.00% vs 2.10%); however, this was not statistically significant ( P=.068). Our analysis demonstrates the benefits of a 2-stent approach for ULMCA patients with high SYNTAX scores and lesions in both major side branches, while the potential benefit of a 1-stent approach for less complex ULMCA was also observed. Further studies with longer follow-up are needed to definitively demonstrate the optimal approach.

A metal matrix composite (MMC) is a composite material with at least two constituent parts, one being a metal matrix and other is reinforcement. When at least three materials are present, it is called a hybrid composite. Aluminium is widely used in aerospace and automobile industries due to its low density and good mechanical properties, better corrosion resistance and wear, low thermal coefficient of expansion as compared to conventional metals and alloys. The aim involved in designing MMC materials is to combine the desirable attributes of metals and ceramics. This project is aimed at development of MMC having aluminium metal matrix with micro-nano particulate zirconium oxide reinforcement. Here aluminium (LM25) has been selected as base metal along with 12% ZrO2 (micro), 12% ZrO2 (nano) and 12% ZrO2 (6% micro + 6% nano) have been taken as reinforcements to produce MMC. The composite has been produced by liquid metallurgy technique (stir casting). The properties of chosen composite are compared with base metal for tension, wear, hardness, density and microstructure analysis. For the combination of Al-LM25 with 12% zirconium oxide (6% micro + 6% nano) the tensile strength (TS) and hardness had increased when compared to that of base metal and are between that of the micro and nano reinforced composite. The density of MMC cast is almost relevant to theoretical densities. For MMC, the wear rate increases for an increase in the speed for a given constant load and time. The microstructure study reveals that Al-LM25 and zirconium oxide have been distributed uniformly throughout the casting with less porosity.

In the present investigation, aerodynamic performance study of NACA 2412 airfoil with surface modifications for the enhanced optimized aerodynamic characteristics is carried out. Three airfoils were built by introducing the cut at different locations. The present work is a computational analysis of the effect of inward cut on the lower surface of airfoil at 25%, 50%, and 75% chord length. The study parameters include flow separation (or stall), lift, drag, and angle of attack. The model is developed in Ansys design modeler and meshed in ICEMCFD. All three meshed models are simulated at 0o, 40o, 80o, 120o and 16o angle of attacks (AoA) at 60000 and 100000 (1 lakh) Reynolds number. The post processing revealed that, the increase in AoA resulted in increase in lift co-efficient (CL) for all three airfoils at both Reynolds number. The lift coefficient started increasing as the position of cut moved towards the trailing edge. The flow started separating after 12o AoA. It was found that, the airfoil with inward cut at 75% of chord length resulted in attaining highest lift co-efficient when compared to other two airfoils.

The aim of current study is to assess the surface wear of outer race of the roller bearing using degradation of grease and analysis of vibration signals. Fourier Transform Infrared Radiation (FTIR) is employed to observe degradation of grease with running hours. Temperature measurement is carried out for bearing using k type thermocouple. Kurtosis value is extracted from time domain signals captured to indicate progressive wear in the bearing. It is found in FTIR spectrum of 450 hours aged grease sample that an absorbance peak occurred around a wavelength of 1750 cm -1 which indicated the formation of oxidation products. Analysis of time domain signals revealed that kurtosis values increased for the bearing after 450 hours of run compared to that of healthy bearing. A maximum bearing temperature of 70°C occurred after 450 hours of run as depicted by temperature indicator. Further, SEM morphology of bearing surfaces illustrated wear tracks and ploughing marks as a result of wear with running hours.

Objective: An aortic supravalvular shelf represents an uncommon congenital cardiac malformation featured by variable extent of left ventricular outflow tract stenosis starting just above the aortic...

In condition monitoring of ball bearings, traditional techniques involving vibration, acceleration may not be able to detect a growing fault due to the low impact energy generated by the relative motion of the components. This study presents an experimental evaluation for incipient fault detection of lightly loaded ball bearings by using acoustic emission method. A table top bearing test rig is fabricated to simulate bearing faults such as inner race & outer race defect etc., with rotating shaft carrying low loads. The effectiveness of the acoustic analysis technique is demonstrated through signal processing techniques; use of Empirical Mode Decomposition (EMD) method to derive the characteristics features related to defective bearings from time domain and enveloped spectra in the frequency domain. The results reveal that the acoustic technique is more effective in detecting bearings’ failure than that of the vibration measurement.

Duplication of inferior vena cava (IVC) is the most common IVC anomaly. We report a successful iliac vein and collateral stenting for venous decompression in a patient with an occluded right femorocaval graft with a duplicated IVC. We also review the literature of embryological development of IVC.

Objective: The goal of current work is to check the suitability of Titanium Nitride (TiN) and Aluminium Chromium Nitride (AlCrN) coatings for the outer race of roller bearings. Methods: Physical Vapour Deposition (PVD) method of coating is employed since it provides less coating thickness. Tribological behaviour is studied for wear rate and co-efficient of friction using PIN-ON-DISC machine. Statistical method of Vibration analysis is performed by extracting values such as kurtosis, skewness, crest factor and RMS from time domain signals captured. Findings: It is revealed in the results that wear rate for TiN coated bearing is 0.03mm3/min which is less than that of AlCrN coated bearing and uncoated bearing. Findings of the vibration study showed that kurtosis value is 7.6 for worn out AlCrN coated bearing compared to 4.4 for worn out TiN coated bearing. This clearly shows that TiN offers better wear resistance which supports the results of wear analysis. It is observed in SEM images of morphological studies that more wear tracks and ploughing marks occurred in uncoated and AlCrN coated bearing surfaces compared to TiN coated bearing. Application/Improvements: Current work provides a good integrated approach for tribological and vibration signal behavior of TiN and AlCrN based PVD coatings thus improving correlation between the two methods and it can be prolonged for prognosis.

We report the management of a patient presenting with haemoptysis due to aortobronchial fistula. He had previously undergone emergency exclusion bypass of a ruptured pseudoaneurysm developing post-aortic coarctation repair. Computed tomography scan showed persistent filling of pseudoaneurysm sac from proximal and distal aortic ligature sites tied during previous exclusion bypass surgery. Successful exclusion of aneurysm was achieved by using 3 vascular plug devices (1 Amplatzer plug II and 2 Amender patent ductus arteriosus occluder devices). We also review types of Amplatzer vascular plugs and their use in peripheral vascular interventions.

We report a case of infra-renal aortic aneurysm which was not suitable for standard endovascular aneurysm repair. Unsuitable neck was reconstructed by dacron graft cuff around the neck with fixing sutures. Following this, standard EVAR was performed.