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In the present study, micro-arc oxidation (MAO) coatings were deposited on shot peened high-strength aerospace aluminium alloys namely 2024-T3 and 7075-T6. The comparative corrosion-fatigue performance was evaluated in 3.5 wt.% NaCl corrosion environment for bare, hard anodized and SP + MAO (prior shot-peened and MAO) coated Al alloys. Also, the corrosion behavior of bare and SP + MAO coated Al alloys was assessed through potentiodynamic polarization (PDP) and electrochemical impedance spectroscopy (EIS) tests. In addition, SP + MAO coatings were characterized for the phase composition, surface/cross-sectional morphologies and surface roughness. Furthermore, the corrosion-fatigue fractured features of coatings were examined to understand the failure mechanisms. The SP + MAO coatings deposited on Al alloys possess superior corrosion-fatigue life as compared to the bare and hard anodized conditions.

Introduction: Hysterectomies are carried out to treat many uterine conditions, and are performed by two principal routes i.e. abdominal and vaginal. However even after many studies, the best route of performing hysterectomy is not clear. Aim: To compare the complications of vaginal and abdominal hysterectomies in treating non-prolapsed cases with good uterine mobility and uterine size less than 12 weeks. Materials and Methods: We carried a prospective, randomized controlled trial on 80 patients requiring hysterectomy for benign diseases at ESI College, Sanathnagar, Hyderabad, Telangana State from May 2016 to September 2017. The sample was categorized into Group A (n=40) in whom non descent vaginal hysterectomy and Group B (n=40) in whom abdominal hysterectomy was performed. The primary outcome measures compared were time of operation, blood loss, post-operative pain, duration in hospital, febrile morbidity and postoperative systemic infections. Results: We found comparable baseline features in both the groups. Mean time of operation, blood loss intra-operatively, was more in Group B (69.82 ± 8.15 minutes, 235 ± 46.89 ml) when compared to Group A (48.36 ± 1.47 minutes, 115 ± 41.35 ml) respectively. Non descent vaginal hysterectomy group showed faster recovery, shorter hospital stay, lesser operative and postoperative morbidity compared to abdominal route. Conclusion: In patients requiring hysterectomy for benign non prolapsed cases, vaginal route may be preferred as it is less invasive, with minimal or no complications, more economical and effective. Keywords: Abdominal hysterectomy, Gynaecology, Intra-operative complications, Non descent vaginal hysterectomy, Postoperative outcome.

Thermal spray techniques have been extensively used to deposit coatings of varying compositions on a variety of industrial components for life enhancement under wear and corrosion prone environments at ambient and high temperatures. A number of components used in power generation systems most commonly encounter high-temperature erosion–corrosion. This review article briefly summarizes various thermal spray techniques and coating characteristics that are relevant to erosion–corrosion applications followed by detailed discussion on the erosion–corrosion fundamentals and testing methods. Further, ambient and high-temperature erosion–corrosion behavior of WC- and CrC-based cermet coatings and oxide coatings have been investigated, compared, analyzed and presented. Based on the analysis of results reported so far, the methodologies to enhance the erosion–corrosion resistance of coatings have been proposed both for ambient and high temperature applications. The future scope of work that needs to be explored to contribute further developments has also been identified and presented.

Micro arc oxidation (MAO) coatings of 5-different thicknesses were formed on 6061-T6 Al alloy with and without prior shot peening. The surface and cross-sectional morphologies, the surface roughness (Ra, Rz), relative phase composition, depth of peening were investigated as a function of MAO coating thickness. The high cycle fatigue performance of Plain MAO and prior shot peened MAO (SP + MAO) coatings were evaluated as a function of coating thickness and maximum alternating stress levels in comparison with that of bare substrate. Independent of the coating thickness, the Plain MAO coatings offer substantial degradation in fatigue life wherein the extent of fatigue debit increases with increasing coating thickness. Increasing surface roughness of Plain MAO coatings with increasing coating thickness resulted in multiple crack nucleation leading to consistent debit in fatigue life. However, irrespective of coating thickness, SP + MAO samples exhibit consistently improved fatigue life over the entire alternating stress range investigated wherein the net effect of increased surface roughness with increasing coating thickness was well-compensated by the compressive residual stresses present beneath the substrate-coating interface. The fractured surface and progressive crack morphologies clearly highlight the mechanisms responsible for the overall fatigue life are distinctly different for the Plain MAO and SP + MAO coatings as a function of coating thickness.

In the modern world, surface engineering technologies have been playing an important role to overcome in-service degradation of ferrous and non-ferrous materials. In this context, the primary objective of this article is to comprehensively review the corrosion behaviour of protective coatings deposited through different surface engineering technologies namely (a) Thermal spray techniques such as plasma spray, high velocity oxy-fuel spray, detonation spray and cold spray; (b) Electrolytic processes including anodizing, hard anodizing, hard chrome plating, electroplating, pulse electrodeposition and micro arc oxidation; (c) Physical vapour deposition techniques namely magnetron sputtering and cathodic arc; (d) sol-gel coatings; and (e) laser materials processing on a variety of non-ferrous materials. The process-structure-property-performance aspects of these coatings are critically reviewed which indeed was the basis for their industrial adaptation in textile, naval, automotive, aerospace, mobile communications, power generation, energy management, electronics and strategic sectors. The critical strategies and challenges associated with each processing technique and the resultant corrosion behaviour were highlighted. In addition, the future R&D direction in each of the aforementioned processes and materials were identified and discussed.

The present study deals with fresh and hardened concrete properties of self-compacting concrete while carrying several trial mixes with a variety of water binder ratio and super-plasticizer content and finally achieved a trail mix with satisfying the flow properties as slump flow, V-funnel, and L-box test apparatus values are obtained within the limits of European guidelines. This study was carried out on the properties of Lightweight self-compacting concrete (LWSCC) with a binder content of 517 Kg/m3. In the achieved proportion of the final trail mix, the coarse aggregate will be replaced by Light Expanded Clay Aggregate (LECA) by varying the different percentages of coarse aggregate as 0%, 10%, 20%, 30%, 40%, and 50% by volume replacement. The fresh concrete properties are determined, and the values were found in considerable range as per European guidelines by performing slump flow, V-funnel, and L-Box tests for various proportions (0%, 10%, 20%, 30%, 40%, and 50%) of LECA aggregates by replacing normal coarse aggregates. The hardened concrete properties are determined by performing Compressive strength, split tensile strength, ultrasonic pulse velocity, and rebound hammer tests after curing specimens for 7 days and 28 days. Results indicate that LECA replacement in SCC up to 30% gives fair results in split tensile & compressive strength. NDT results show values are gradually decreasing with an increase in LECA proportion. Beyond 30% of LECA replacement in SCC gives results of split tensile, compressive strength, ultrasonic pulse velocity, and rebound hammer tests which are not inconsiderable range.

Thermally-sprayed tungsten carbide (WC)-based cermet coatings have been widely used for a large variety of wear resistance applications. More recently, these coatings are being used as an alternative to hard chrome plating, especially in the aerospace and automotive industries. Utilizing the automated spray systems and the commercial availability of spray grade powders with different compositions, the WC-based cermet coatings that are conventionally used for wear protection are now being extended for simultaneous corrosion protection. Therefore, the corrosion behavior of various WC-based cermet coatings as a function of matrix composition, feedstock type and deposition technique exposed to a variety of corrosion mediums has been critically reviewed. The corrosion mechanisms of WC-based cermet coatings studied using various analytical tools have also been comprehensively discussed. The interrelationship between the microstructural integrity and the corrosion behavior has been critically assessed. Further, the influence of pre- and post-treatments to improve the overall corrosion resistance of the coatings has also been highlighted.

The micro arc oxidation (MAO) coatings of 50 ± 5 µm thickness were deposited on 6061-T6 Al alloy substrates with and without prior shot peening. The peening was carried out using 3-different shot materials namely cast steel, glass beads and alumina having 3-different sizes, each ranging from 212 to 850 µm, at a blast pressure of 1.5 bar and 2.5 bar. The bare, hard anodized, plain MAO and prior shot peened MAO (SP+MAO) coated 6061-T6 Al alloy as a function of (a) maximum alternating stress (5 - different stress levels) (b) shot peening medium (3 - different shot materials) (c) shot sizes (3 - different size ranges for each shot material) were subjected to rotating bending high cycle fatigue tests (R = −1) and the average number of cycles to fail was calculated. The surface residual stresses as well as the residual stress state of the substrate beneath the substrate-coating interface (sub-interface) were analyzed through Sin 2 ψ method using conventional and micro X-ray diffraction (XRD) techniques. The results obtained were utilized to understand the effect of surface roughness, surface and sub-interface residual stresses, nature of crack propagation and its deflection on the resulting fatigue life. While both the plain MAO and hard anodized coatings significantly degrades the fatigue life, the prior shot peening followed by MAO coating enhances the fatigue life much better than the bare substrate. On contrary, depending upon the peening parameters employed, the prior shot peening need not guarantee the fatigue life improvement was also noticed. To address this ambiguity, an approach based on integration of shot peening parameters into the “kinetic energy” which is correlated with the “bench mark ratio” (BMR = ratio of fatigue life of coated to the un-coated) as proposed in the present study clearly illustrate the preferred operating window of shot peening parameters resulting in enhanced the fatigue life over 1000–1200% than the corresponding bare substrate.

The corrosion-fatigue response of Al alloys becomes an important consideration for qualifying them for aerospace and other structural applications, the MAO coatings with three different thicknesses namely 10 µm, 50 µm and 90 µm were provided on peened (SP + MAO) and un-peened (Plain MAO) substrates. Further, the corrosion (potentiodynamic polarization) tests in 3.5 wt% NaCl solution and corrosion-fatigue tests at 5-different maximum alternating stress levels were evaluated for each material condition. In addition, the surface roughness, surface and cross-sectional coating morphologies in as deposited and corroded conditions; fractured morphology and corrosion-fatigue crack propagation features were evaluated; correlated with the corresponding corrosion rates and corrosion-fatigue life. The results obtained highlight the role of corrosion medium in significant degradation of corrosion-fatigue life as compared to the plain-fatigue life of both bare substrate and MAO coated conditions. A new parameter namely the normalized corrosion-fatigue life index (NCFI) provides a quicker insight and possible benchmarking of the coating’s ability to withstand the damaging action of simultaneous corrosion and fatigue. A 50 µm thick SP + MAO coating was identified as a candidate choice to withstand diverse degradation modes namely the simple corrosion, plain-fatigue and corrosion-fatigue.

Background: In India almost 65% of the women have an unmet need for family planning in the first postpartum year. Increasing rates of institutional deliveries creates an opportunity for providing quality post-partum family planning services. Post-partum Intrauterine contraceptive device (PPIUCD), a form of long acting reversible contraception (LARC) is one of the most affective and safest method available. The present study aims at evaluating the safety, efficacy, rate of acceptance and rate of discontinuation of Intra caesarean inserted contraceptive device Copper T-380A.Methods: This was a prospective study conducted at ESIC Medical College, Sanathnagar in women delivered by caesarean section during the period between March 2018 to February 2019. Recruitment was done based on the WHO medical eligibility criteria (MEC) for PPIUCD and also their willingness to participate in the study. Follow-up visits were scheduled at 6 weeks, 3 months and 6 months.Results: Of the 265 women fulfilling the WHO MEC, 180 (67.92%) were willing to participate in the study. Total acceptance rate was 67.7%. Majority of them belonged to the age group 21-30 years (80%) and para 2 (53.88). 93.3% of the women were literates. 12 (6.66%) cases lost to follow up and the complications were studied in the rest 168 women. During follow up -38.69% had missing strings, 12.5% menstrual disturbances, 4.76% abdominal pain and spontaneous expulsion in 4.1%. No cases of perforation and pregnancy were reported. Total continuation rate was 84%.Conclusions: PPIUCD is a safe and convenient option of contraception with low expulsion rates and high continuation rates.

Copper Tin Sulphide is a leading prospect in thin film hetero-junction solar cells owing to its germane electrical and optical properties. It is a ternary direct band gap p-type amalgam with substantial potential significance in thin film solar cells. Its components are innocuous, copious in earth crust and inexpensive. This treatise seeks to delineate the deposition of CTS thin films on soda-lime glass substrate by a jejune sol-gel spin coating technique at distinct temperatures. The upshot of annealing temperatures on the development and properties of the films are examined by exploring their optical, structural, morphological properties using apposite characterization methods. XRD analysis avers genesis of cubic structure of CTS. SEM investigation reported adequate facet for solar cells. The optical quantifications reveals that the gap between the energy bands of the films decline from 1.61eV to 1.45eV after annealing. Suchlike energy gap magnitudes are optimal for semiconducting materials as an imbiber layer of thin film solar cells.

Intervehicular correspondence (IVC) is a fundamental gifted inspect part with the point of be assessed toward essentially make an installment in the method for trade wellbeing notwithstanding great association. inside this system, endless practical IVC applications add to the all inclusive call for in backing of quick multihop intervehicular communication transmission,counting in arrangement such like situation,trend,with rate. then again, it is discriminating intended for such an insights substitute characterization toward exist sturdy just before assurance assaults. similarly, a derisive auto force present broken thus inspired by the intervehicle remote affiliations, most critical close presence alongside trusts sufferers before toward at all extra sort of illdisposed enthusiasm toward oneself (e.g., exchange redirection utilized for the antagonistic benefit). inside this archive, we explore assaults just before the breakthrough IVC-based asylum applications. furthermore, this breakdown drives us set out toward point a quick and additionally ensured multihop transmit calculation intended for vehicular proclamation, which is demonstrate while in transit to exist adaptable toward the aforementioned assaults.

The existing national policy framework vis-à-vis vaccines reflects an aggressive push towards introduction of new vaccines in the Universal Immunisation Programme (UIP) without providing an uncompromising scientific basis or committing itself to proven epidemiological needs of the population. The idea of selective immunisation is being undermined by slogans like ‘prevention is better than cure’ that are being trumped up to impart credibility to the effort, given shape by the projected panacea for all ills, that is, Public–Private Partnership (PPP), to push the line that all immunisation is universal. This article examines the aims and motives behind deliberate destruction of the public sector in favour of PPPs and establishes the need for a vaccine policy that is designed to enhance national public capacity for public immunisation programmes as opposed to the present policy that justifies spending public money on privately produced vaccines in the name of protection from diseases whose incidence figures and public health statistics are dubious and industry-manufactured.

This paper is about designing a silicon based piezoresistive micro pressure sensor for greater sensitivity. Using Finite Element Analysis (FEA) the role played by important design parameters like the side length and the thickness of the pressure sensing membrane in determining the sensitivity of the sensor are studied in detail for a pressure of 100 kPa. The fracture stress of silicon is adopted as the main criterion for selecting the dimensions of the diaphragm in order to obtain maximum sensitivity and to ensure safe sensor operation. From the FEA results the side length and the thickness of the sensor are determined as 1000 µm and 17.2 µm respectively. The stress profile of the diaphragm is studied in order to determine the optimum length and positioning of piezoresistors. The piezoresistors are placed in six different patterns and the sensitivity of the sensor for each pattern is determined. The maximum sensitivity is found to be 41.6 mV/V/Bar. The effect of variation in the length of the piezoresistor on the sensitivity of the sensor has been studied and the optimum length of the piezoresistor is determined as 100 µm.

Background: Ceiba pentandra seeds belonging to order Malvalea and the family Malvaceae, commonly known Kapok were evaluated for their phytochemical ingredients and antioxidant activity. Materials and methods: Soxhlet extraction method was used for the extraction of oil, phytochemicals and antioxidant activities of Ceiba pentandra seed oil was estimated by well-known methods. Results: The seed oil was extracted using soxhlet extraction method with analytical grade hexane as refluxing solvent. The oil was thick yellowish in colour having pungent odour with a yield of 40%. Phytochemical constituents and non enzymatic antioxidants showed enhancement in increasing concentration from 25 mg/mL to 100 mg/mL. At 100 mg/mL recorded phytochemical components phenols, flavonoids, alkaloids and tannins were 305 μg gallic acid equivalents g-1, 3207 μg quercetin equivalents g-1, 0.34 μg boldine equivalents g-1 and 2041 μg tannic acid equivalents g-1 respectively. The seed oil exhibited striking Diphenyl picryl hydrazyl radical scavenging Assay (DPPH), Ferric reducing or Antioxidant power assay (FRAP), reducing power assay and Hydroxyl radical scavenging activity. The measured DPPH activity at 100 mg/mL was 47.56% of inhibition per 50 μL of oil as compared to 45 and 76% of inhibition per 1 mg/mL of Rutin and BHT as positive controls. Observed FRAP ability of Ceiba pentandra seed oil was 309 FRAP units at 100 mg/mL concentration, reducing activity of Ceiba pentandra seed oil was observed at 100 mg/ mL as 20.52 μg of ascorbic acid equivalents per mL of oil. Hydroxy radical scavenging activity of Ceiba pentandra seed oil observed as 39.69% inhibition/0.1 of oil at 100 mg/mL, as compared to positive controls, Ascorbic acid and BHT at 1 mg/mL with percentage of inhibition 75 and 75.6 respectively. Conclusion: The importance of the phytochemical constituents and non-enzymatic activities of Ceiba pentandra seed oil in the maintenance of health is strengthened as trend of the future is moving towards using seed oil as medicine in the management of various chronic diseases.

The latex is widely used in cosmetics, pharmaceuticals and food industry as in paper, textile and petroleum industries also. The present study was carried out to assess the potential antimicrobial activity of methanolic, ethanolic and chloroform extracts of fruit latex of Artocarpus communis against different pathogenic bacteria and fungus. All three extracts were found to show good to moderated activity against bacteria namely Gram +ve (Bacillus cereus, Bacillus subtilis and Staphylococcus aureus) and Gram –ve (Escherichia coli and Pseudomonas aeurignosa) and fungal stains namely Aspergillus flavus, Aspergillus niger, Candida albicans and Saccharomyces cerevisiae. In methanolic extract major activity was perceived on bacteria Bacillus subtilis and among fungi Aspergillus niger. In ethanolic extract maximum activity perceived on bacteria Escherichia coli and amongst fungi Aspergillus flavus. In chloroform extract determined activity was observed on bacteria Staphylococcus aureus and between fungus Candida albicans. Maximum activity was observed on bacterial strains compared with fungal strains. In all three extracts Minimum inhibitory concentrations were in the range of 12.5-25 mg/ml. In addition, quantitative phytochemical estimations of assured active compounds like Total phenolics, flavonoids, tannins, proteins, carbohydrates, glycosides, and alkaloids were found to be in considerable quantities.