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Objective: The aim of the study was to evaluate the surgical characteristics of the proximal femoral nail and dynamic hip screw stabilisation for intertrochanteric fractures. Methods: After the ethical approval from the institutional review board, this randomized controlled trial, was conducted at Orthopaedic Department, Jinnah Post Graduate Medical Centre, Karachi, from 29th July 2018 to 28th January 2019 through the non-probability consecutive sampling, 100 participants were recruited for the present study. Radiographs of the pelvis with both hips anteroposterior view and traction-internal rotation view were taken. proximal femoral nail was used in group A while dynamic hip screw was used in group B. At the end of the surgery, time and blood loss were calculated and independent t-test was applied for comparison. Effects were addressed through Stratification. P-value ≤0.05 was taken as significant. Results: There were 72% male and 28% female patients in group-A and 68% male and 32% female patients in group-B. The mean fracture duration in group-A and group-B was 3.52±1.41days and 3.54±1.45 days respectively. Mean operative time in group-A and group-B was 91.32±8.10 minutes and 73.20±12.52 minutes respectively while mean intraoperative blood loss was 188.34±25.80 ml and 255.44±14.56 ml in group-A and group- B respectively. These differences were found significant. Conclusion: Group A had a longer mean surgical duration and considerably less mean intra-operative blood loss as compared to group B. Keywords: Operative Parameters, Intertrochanteric Fractures, Proximal Femoral Nail, Dynamic Hip Screw

The growing population in urban areas generates large volumes of hospital waste which intensifies the problem of hospital waste management in developing countries. This study is designed to evaluate environmental impacts associated with hospital waste management scenarios using life cycle assessment (LCA) approach. Two scenarios were designed to describe the current practices: (scenario A) and an integrated approach (scenario B), which includes segregation and recycling of hospital waste. Data were collected from five public hospitals located in the district of Sheikhupura, Pakistan. The collected hospital waste was quantified and categorized on a daily basis for five consecutive months (October 2020 to February 2021). The functional unit was defined as one tonne of hospital waste. System boundaries for two scenarios include segregation, transportation, treatment and disposal of hospital waste. After defining functional unit and system boundaries, LCA was conducted using the IGES-GHG simulator. The scenarios were evaluated using common parameter, i.e., greenhouse gas (GHG) emissions. Scenario A and scenario B resulted in net GHG emissions of 1078.40 kg CO2-eq. per tonne of waste and 989.31 kg CO2-eq. per tonne of waste, respectively. Applying an integrated approach, it would be possible to mitigate GHG emissions of 37,756.44 kg CO2-eq. per tonne of waste annually and to recover some materials such as glass, paper, plastic and metals. Therefore, implementing an integrated approach for the management of hospital waste will progress the entire system towards sustainability. The findings of this study can be used for future research and policymaking.

Prediction of financial distress is a significant issue for any company. At present Non-Banking Financial Institutions (NBFIs) represent one of the most important parts of a financial system in Bangladesh. NBFIs contribute a lot to the GDP growth of Bangladesh. So, it has become very essential for the companies to predict the insolvency in advance for taking their important decisions for the betterment. The purpose of this paper is to predict the solvency and the factors that have an impact on the solvency by analyzing the financial statements for a period of 5 years(2013 to 2017) of 20 Dhaka Stock Exchange (DSE) listed Non-Banking Financial Institutions (NBFIs) including asset finance or leasing companies, investment finance companies and housing finance companies of Bangladesh by using Fulmer H score model and Springate Z score model. The findings indicate that according to Fulmer Model few sample NBFIs are in risky zone and according to Springate model all the sample NBFIs are in distress zone. The study suggests that according to the context of Bangladesh Fulmer H Score model is more appropriate compared to Springate Z Score model for predicting solvency.

A major problem faced by Phase Change Materials (PCM) based latent heat thermal energy storage systems is the slow thermal response. In this study, the feasibility of nano phase change materials composites is investigated experimentally by using various types of nanoparticles in PCM, to improve thermal response by increasing the thermal conductivity. Heat transfer enhancement of PCM composites (RT26 and coconut oil) is achieved by acquiring better thermophysical properties through seeding nanoparticles in PCM. RT26 and coconut oil are beneficial due to the absence of corrosion to metallic containers. A thermal response investigation is conducted with a flat slab type latent heat thermal energy storage unit. It was observed that the increase in thermal conductivity of PCM by seeding nanoparticles is useful for the improvement of heat transfer. Carbon nanotubes have shown better performance as compared to Al2O3 and Fe3O4 nanoparticles. It was further analyzed that at a 1 wt percent concentration of nanoparticles, the maximum heat transfer enhancement in RT26 caused by Fe3O4, Al2O3 and carbon nanotubes nanocomposites is up to 20.01, 36.68 and 64.21% respectively. The maximum heat transfer enhancement in coconut oil caused by Fe3O4, Al2O3 and carbon nanotubes nanocomposites is up to 8.83, 14.84 and 33.38% respectively. Therefore, it is revealed that RT26 has more potential for heat transfer enhancement as compared to coconut oil. This is due to the percentage improvement in the thermophysical response of RT26 as compared to coconut oil. The economic and environmental analysis was conducted to compare the performance of latent heat thermal energy storage unit with and without the application of nanoparticles in PCM, to estimate the most viable candidate among various nano composites. The economic analysis presented the lowest annual energy running cost and Net Present Value(NPV) for nanocomposite of carbon nanotubes in RT26 is Rs.-4381 and RS.-36375 respectively. Whereas the maximum annual energy cost and NPV for pure RT26 are Rs.-12240 and Rs. -75548 respectively. The NPV for Fe3O4 and Al2O3 is Rs.-62207 and Rs.-53062 respectively. The cost and NPV were Rs.-6646 and Rs.-55226 in the case of carbon nanotubes in coconut oil. It shows that the trend is the same in the case of Fe3O4 and Al2O3 nanoparticles in both RT26 and coconut oil, unlike of carbon nanotubes. The environmental analysis shows that the maximum and minimum payments of carbon dioxide by carbon nanotubes and Fe3O4 nano composites respectively in RT26, are Rs.7000 and Rs.2176. While the corresponding values are Rs.2975 and Rs.798 in the case of coconut oil. Hence, carbon nanotubes in RT26 have the highest economic and environmental viability. Accordingly, the enhancement in heat transfer using these nanoparticles will be helpful in air conditioning applications like animal houses.

Researchers in developed countries argue that banks should be free to decide about their sustainability initiatives without the interference from regulators. However, researchers in developing countries tend to think differently. This study aimed to focus on this argument by examining the linkage between sustainability and financial performance (SFP) aided through regulatory policy guidelines. In doing so, a comparative study was conducted between 2012 and 2018 to compare the pre- and post-status of SFP due to implementation of policy measures. Environmental, social and governance (ESG) scores were calculated and related with financial performance (return on assets) through regression analysis. The sample data includes 30 private commercial banks (PCBs) in Bangladesh. The analysis of the data shows that during these years, the overall sustainability performance, i.e., environmental, social and governance scores of the banks increased by 33 percent. However, the transformation of this performance into better financial performance could not been established even when age and size were taken into account. The current turbulent state of the banking sector due to growing non-performing loan has been identified as the single most influential factor for this neutral result. Research findings suggest that policy guideline initiatives do have a positive impact on bank sustainability. However, exogenous factors, such as political interference, may appease, deviate and prolong its impact on financial performance. This work will enhance the understanding of academics and policy-makers about the feasibility and impact of the policy-led sustainability model in the banking sector, particularly in developing countries.

This paper presents a condition monitoring technique for the identification and correction of faults in reciprocating machines by recording engine vibration signals arising from different processes. The proposed data acquisition set-up allows the analyst to record vibration signals from different locations, analyse them and make the appropriate decisions regarding predictive maintenance. Data are recorded before and after carrying out major overhauling to assess the effectiveness of the proposed condition monitoring technique. For a complete health assessment, vibration signals and ultrasonic signature with respect to the crank angle are recorded and interpreted. All of the data are obtained at constant engine speed to depict the mechanical condition of the components and indicate any poor performance. A scuffed main bearing and a broken piston ring are diagnosed successfully. Suspected components are replaced based upon the findings of the initial analysis and data are recorded again to verify the results. Post-evaluation data confirm a normal mechanical condition and satisfactory performance except for some initial friction. The main objective of this experimentation is the identification of major tasks related to maintenance prior to major overhauling. This work shows that the use of non-intrusive condition monitoring techniques can reduce the frequency of failures by identifying developing faults.

Condensate retention has been found an important parameter for heat transfer on horizontal enhanced condensing tubes. In this research, five pin-fin (varying in circumferential pin spacing) and three integral-fin horizontal tubes are investigated for condensate retention angle (which is measured from the top of tooth to the fully flooded flank) using water-ethanol mixture. An attempt was made to find the optimum concentration of ethanol in water for maximum retention angle. Concentration of ethanol was varied in between 0.5% to 1.5% by weight. Data revealed the importance of integral-fin tube over pin-fin tube as significant increase in retention angle was observed for integral-fin tube ((having same longitudinal spacing, tooth thickness, tooth height, inner and outer diameter) while retention angle for pin-fin tubes remain unchanged. Optimum ethanol concentration was observed to be 0.75%.

Microchannels with microencapsulated phase change slurry (mPCM) have gained attention due to their compactness and large surface area to volume of fluid ratio. The phase change process also helps in sustaining high heat exchange over small temperature changes. This paper is focused on numerical investigation of heat transfer characteristics of mPCM slurry flow during its freezing phase in microchannels under convective boundary conditions. The phase change process was incorporated in numerical modeling by considering the rectangular profile of an effective specific heat capacity model. Numerical simulations were peformed for mPCM slurry with 5 to 15% mass concentration, and the results were compared with those obtained with pure water. The effects of mass concentration of mPCM slurry on pressure drop, local Nusselt number, and local temperatures along the length of the channel were investigated. It was noticed that the increase in mass concentration enhanced the local Nusselt number than pure water. At the outlet of microchannel for flow velocity of 0.55 m/s, the bulk and surface temperatures were found to be 3.12 K and 1.2 K higher than those recorded with pure water. With a mass concentration in 5–15% range the pressure drop for mPCM slurry was found to be 5.1–36% higher than the pure water case.

Addition of a small amount of nanoparticles to the working fluids of a parabolic trough collector does not only enhance the heat transfer properties and thermal conductivity of basefluid but also improves the thermal efficiency of the system. The current investigation presents a comparative analysis of experimental performance of a conventional parabolic trough collector and direct absorption parabolic trough collector for capturing solar thermal energy. Two separate nanomaterials, Al2O3 (with high scattering properties) and CuO (with high absorption properties), were selected for the preparation of the hybrid nanofluids. A customized experimental setup was developed to evaluate their photothermal performance. The nanofluid samples in the concentration range of 0.01–0.5 wt% were investigated under a natural solar flux. Thermal efficiency of conventional parabolic trough collector was increased by 31% using hybrid nanofluid as compared to basefluid. The thermal efficiency enhancement of direct absorption parabolic trough collector was observed as 19% higher than that of conventional parabolic trough collector due to higher heat transfer rate, solar trapping and volumetric absorption. These binary nanofluids can be potential working fluids in various applications based on solar thermal energy.

Nano-structured energetic materials have been recently proposed as novel energy storage media where the exothermic reaction is the key to control the heat release process. The properties of nano-alloys, which can be engineered not only by the particle size, but also by varying their elemental compositions, are very appealing. This work conducted a comparative experimental study of the exothermic characteristics of two nanomaterials in the air, aluminum nanoparticles (nano-Al) and aluminum–copper nanoalloys (nano-AlCu) based on TGA/DSC studies. The results showed that the general exothermic characteristics of nano-AlCu were very similar to that of nano-Al but the nanoalloy was more reactive. The nano-AlCu was oxidized and ignited at lower temperature, and influenced by the heating rate. An early ignition was found for both nanomaterials, and the eutectic melting of the nano-alloy was believed to be mainly responsible for its early ignition.

This work investigated the oxidation, ignition, and thermal reactivity of alloy nanoparticles of aluminum and copper (nAlCu) using simultaneous thermogravimetric analysis (TGA) and differential scanning calorimeter (DSC) method. The microstructure of the particles was characterized with a scanning electron microscope (SEM) and transmission electron microscope (TEM), and the elemental composition of the particles before and after the oxidation was investigated with energy dispersive X-ray spectroscopy (EDS) and X-ray diffraction (XRD). The particles were heated from room temperature to 1200 °C under different heating rates from 2 to 30 K/min in the presence of air. The complete oxidation process of the nAlCu was characterized by two exothermic and two endothermic reactions, and the reaction paths up to 1200 °C were proposed. An early ignition of nAlCu, in the temperature around 565 °C, was found at heating rates ≥ 8 K/min. The eutectic melting temperature of nAlCu was identified at ∼546 °C, which played a critical role in the early ignition. The comparison of the reactivity with that of pure Al nanoparticles showed that the nAlCu was more reactive through alloying.

The oxidation and ignition of aluminum nanoparticles with a mean diameter of 150 nm are investigated with the help of simultaneous thermal analysis, X-ray powder diffraction, energy dispersive X-ray spectra analysis (EDS) and scanning and transmission electron microscopy at heating rates of 2-30 K min(-1). A unique early ignition reaction is observed when the heating rate is ≥8 K min(-1) and there is a co-existence of various polymorphs of alumina (γ-, δ-, θ-, and α-Al2O3) below the melting temperature of aluminum nanoparticles. It is proposed that such an early ignition reaction is due to a combined effect of solid phase transformation of the alumina shell and the early melting of the aluminum core, and is responsible for the co-existence of various polymorphs of alumina at the low temperature. The ignition temperature increases approximately with the increase of the heating rate. Regardless of the heating rate, the oxidation scenario can be described by a three-stage reaction with the main reaction occurring before the melting of aluminum nanoparticles.