Expanding hot flow in the black hole binary SWIFT J1753.5-0127: evidence from optical timing

We describe the evolution of optical and X-ray temporal characteristics during the outburst decline of the black hole X-ray binary SWIFT J1753.5-0127. The optical/X-ray cross-correlation function demonstrates a single positive correlation at the outburst peak, then it has multiple dips and peaks during the decline stage, which are then replaced by the precognition dip plus peak structure in the outburst tail. Power spectral densities and phase lags show a complex evolution, revealing the presence of intrinsically connected optical and X-ray quasi-periodic oscillations. For the first time, we quantitatively explain the evolution of these timing properties during the entire outburst within one model, the essence of which is the expansion of the hot accretion flow towards the tail of the outburst. The pivoting of the spectrum produced by synchrotron Comptonization in the hot flow is responsible for the appearance of the anti-correlation with the X-rays and for the optical quasi-periodic oscillations. Our model reproduces well the cross-correlation and phase lag spectrum during the decline stage, which could not be understood with any model proposed before.Comment: 13 pages, 11 figures, MNRAS submitte

Measurement of thermal and electrical conductivities of graphene nanofluids

This paper was presented at the 3rd Micro and Nano Flows Conference (MNF2011), which was held at the Makedonia Palace Hotel, Thessaloniki in Greece. The conference was organised by Brunel University and supported by the Italian Union of Thermofluiddynamics, Aristotle University of Thessaloniki, University of Thessaly, IPEM, the Process Intensification Network, the Institution of Mechanical Engineers, the Heat Transfer Society, HEXAG - the Heat Exchange Action Group, and the Energy Institute.The current work experimentally investigates the thermal and electrical conductivities of nanofluids containing graphene sheets that have very high thermal conductivity. Here, the graphene is prepared from natural graphite by oxidation-reduction process through a single step method. The graphene nanofluid thus obtained exhibited greater stability even after six months of preparation without addition of any surfactants. The detailed characterization process involving TEM, UV absorption and DLS measurements revealed the well dispersed nature of nanofluid with sheets appropriately interconnected and entangled. The DLS measurement indicates a trimodal size distribution of graphene sheet ranging from 5nm to 1500nm. It was also found that the absorption peak of the sample was 269 nm. This reveals the complete reduction of graphene oxide to graphene and the value is in good agreement with the literature. The thermal conductivity is measured using the traditional Transient Hot Wire (THW) method and enhancements are substantial even at lower concentrations while such behaviour is not predicted by the classical Maxwell theory. The thermal conductivity of graphene nanofluids are measured for different concentrations of 0.01 - 0.2 volume % at different temperatures. It is observed that the thermal conductivity increases with increase in concentration of grapheme, which is as expected. The maximum enhancement obtained is 27% at 0.2% concentration. The enhancement also shows a strong temperature dependence which is unlike that of its carbon predecessors like CNT and graphene oxide nanofluids. Electrical conductivity is measured using a 4 cell conductivity meter with inbuilt automatic temperature compensation. Electrical conductivity enhancement is found to be linear with increase in graphene volume fraction

An Advanced Real Time Lead RF-MEMS Based Switch Design for AI Applications

The artificial intelligence-based MEMS switch designs have been led technology in present micro-electronic applications. The 4G and 5G communication hardware networks have working been through RF-MEMS switches. The earlier MEMS deigns are outdated in terms of functionality and compatibility, so that a realistic RF-MEMS based advanced configurations are compulsory for future electronic applications. In this research work 2 different shunt-capacitive type configurations have been implemented and those are verified on COMSOL Multi-physics toolbox as well as functionality been verified on HFSS software tool. The electromechanical properties of proposed shunt type RF-MEMS switch attained more perfection in functionality compared to past configurations. The implemented switching model has uniform meandering and derives pull-in-voltage of 18.5v along with 1.2xs switching time. The 2nd type shunt RF-MEMS model has been generated pull-in-voltage of 25.5v and isolation loss of 37.20.  The performance metrics like Length 25.34 µm, Width 28.92 µm and Thickness 34.42 µm had been improved compared to previous models. The deigned shunt-capacitive type RF-MEMS models are most prominent in operation and offering advanced microelectronics applications

Entrepreneurship Education: Engineering a Pracademic Approach

Innovation and entrepreneurship are becoming increasingly important as we rely on economies to create jobs around the globe. And yet, considering the myriad and dynamic business environments of the 21st century and ever increasing consumer power, the risk of entrepreneurial activity has increased considerably. Consequently, we need to educate engineers in an innovative manner and fundamentally change the teaching methods, curriculum, and research in entrepreneurship education. Applying the scholarship of teaching and learning (SoTL) to entrepreneurship with similar rigor can increase the odds of being successful engineering entrepreneurs. Still, faculty and administrators of engineering programs are hesitant to introduce courses into an engineering curriculum outside of engineering fundaments. The paradox, however, is that non-core engineering courses including leadership and engineering management can help students develop highly desired attributes that contribute to career and industry success. In this paper, the authors look at current trends in entrepreneurship education and will propose a potential new approach to innovation and entrepreneurship education for engineers in the 21st century. This approach will focus on pracademic (practical / professional and academic) learning concepts that are both engaging and worthwhile for student-centered learning. Supplementary pedagogical approaches are necessary to augment classroom learning for aligning active-learning topics within innovative course frameworks. This new approach will focus on four topics: innovation in teaching methods, introducing leadership education into the entrepreneurship curriculum, quality within systems engineering management, and using rigorous research to drive transformational change in entrepreneurship education. The pracademic approach will be taught as a workshop series or as courses in the entrepreneurship domain and will be presented as part of this paper where methods, leadership, quality, and rigorous research are the central tenets the authors propose for serious and thrivable consideration

An Advanced Real Time Lead RF-MEMS Based Switch Design for AI Applications

The artificial intelligence-based MEMS switch designs have been led technology in present micro-electronic applications. The 4G and 5G communication hardware networks have working been through RF-MEMS switches. The earlier MEMS deigns are outdated in terms of functionality and compatibility, so that a realistic RF-MEMS based advanced configurations are compulsory for future electronic applications. In this research work 2 different shunt-capacitive type configurations have been implemented and those are verified on COMSOL Multi-physics toolbox as well as functionality been verified on HFSS software tool. The electromechanical properties of proposed shunt type RF-MEMS switch attained more perfection in functionality compared to past configurations. The implemented switching model has uniform meandering and derives pull-in-voltage of 18.5v along with 1.2xs switching time. The 2nd type shunt RF-MEMS model has been generated pull-in-voltage of 25.5v and isolation loss of 37.20.  The performance metrics like Length 25.34 µm, Width 28.92 µm and Thickness 34.42 µm had been improved compared to previous models. The deigned shunt-capacitive type RF-MEMS models are most prominent in operation and offering advanced microelectronics applications

Management of Pain in Children with Burns

Burn injuries are common in children under 10 years of age. Thermal injury is the most common mechanism of injury and scalds account for >60% of such injuries. All children with burns will experience pain, regardless of the cause, size, or burn depth. Undertreated pain can result in noncompliance with treatment and, consequently, prolonged healing. It is acknowledged that the monitoring and reporting of pain in children with burns has generally been poor. Due to the adverse physiological and emotional effects secondary to pain, adequate pain control is an integral and requisite component in the management of children with burns. A multidisciplinary approach is frequently necessary to achieve a robust pain relief. Key to successful treatment is the continuous and accurate assessment of pain and the response to therapy. This clinical review article discusses the essential aspects of the pathophysiology of burns in children provides an overview of pain assessment, the salient principles in managing pain, and the essential pharmacodynamics of commonly used drugs in children with burn injuries. Both pharmacological and nonpharmacological treatment options are discussed, although a detailed review of the latter is beyond the scope and remit of this article

The Role of Physical Activity on Insulin Resistance-Associated Endothelial Dysfunction

Enhanced physical activity and cardiorespiratory fitness significantly impact morbidity and mortality across the spectrum of noncommunicative chronic illnesses experienced by modern lifestyles. Physical activity itself prompts an intricate interplay of physiological responses across vital organ systems including microvascular adaptations to optimize nutrient, oxygen, and hormone delivery, some of which involves insulin-mediated regulation. Insulin has been known to act on the vasculature in multiple ways by its effects on endothelium and skeletal muscle blood flow. This is important to understand as it has implications for conditions associated with insulin resistance (IR) such as obesity, metabolic syndrome, prediabetes, diabetes, and polycystic ovarian syndrome among others. These conditions are associated with increased morbidity and mortality contributed by endothelial dysfunction via increased atherosclerosis, hypertension, and increased free fatty acid levels. In this chapter, we will discuss the effects of insulin on the vasculature, IR on the endothelium, and lastly, what impact physical activity may have on such processes

BENTHIC FORAMINIFERAL AND ITS ENVIRONMENTAL DEGRADATION STUDIES BETWEEN THE TSUNAMIGENIC SEDIMENTS OF MANDAPAM AND TUTICORIN, SOUTH EAST COAST OF INDIA

The Gulf of Mannar is a transitional zone between the Arabian Sea and Indian Ocean proper and is connected with the Bay of Bengal through a shallow sill, the Palk Strait. The study area extends from Mandapam to Tuticorin on the southern coast of Tamil Nadu (India) over a distance of 120 km. It is bound in the northeast by Rameshwaram Island, in the east by the Bay of Bengal, in the west by the Eastern and Western Ghats, and in the south by Tuticorin. A total of 36 sediment samples were collected from the beach (6) and the offshore (30) area in the study region. The offshore samples were collected at six transects keeping the stations at Mandapam (5 nos), Valinokkam (5 nos), Vaippar (5 nos), Vembar (5 nos), Kallar, (5 nos) and Tuticorin (5 nos). Totally, 77 benthic foraminiferal species (Post-tsunami) and varieties belonging to 39 genera, 13 families, 10 superfamilies and 4 suborders have been reported and illustrated. The following species are widely distributed in the pre and post-tsunami samples namely Spiroloculina communis, Quinqueloculina elongatum, Q.lamarckiana, Q. seminulum, Triloculina trigonula, Cibicides lobatululs, Ammonia beccarii, A. dentata, A.tepida, Elphidium crispum and Assilina ammonoides. Grain size studies shows the frequency curves vary from unimodal to bimodal in places of river discharge from the Vembar, Kallar, Vaippar and Tamiraparani, as a result of which an additional sub-population is deposited. At Mandapam and Tuticorin, the total species are increasing in the deeper depths whereas in Kallar there will be reverse trend which decreases with depth. Similarly, the living species also have the same trend at Vallinokkam. The scatter plot of salinity versus living species shows a positive correlation. The scatter plot of organic matter versus living species shows strong negative correlation and positive correlation with dead species showing a negative relation with the biomass. Further, the trend of organic matter vs. carbonate indicates that the littoral drift of sediments brought foraminifera from the inner shelf regions and has played a great role in the contribution of dead species, as well as microfossils. The present study indicated that the sediments were brought from the inner shelf

DEVELOPMENT AND VALIDATION OF STABILITY INDICATING RP-HPLC METHOD FOR SIMULTANEOUS ESTIMATION OF BECLOMETHASONE DIPROPIONATE AND SALBUTAMOL SULPHATE

Objective: To develop a validated stability indicating reverse phase high performance liquid chromatography (RP-HPLC) method for simultaneous estimation of Beclomethasone dipropionate (BEC) and Salbutamol sulphate (SAL) in bulk and combined dosage form.Methods: An isocratic, RP-HPLC method was developed using Hi Q Sil C18 (250 x 4.6 mm, 5 µm) column and 1 mM ammonium acetate buffer and methanol (15:85 v/v) as mobile phase at flow rate of 1 ml/min and detection wavelength of 230 nm.Results: The chromatographic conditions yield good separation between drugs with retention time (RT) of 7.75±0.03 min and 2.36±0.09 min, for BEC and SAL, respectively. The method was validated with respect to linearity, precision, accuracy and robustness. The data of linear regression analysis indicated a good linear relationship over the range of 5–30 µg/ml concentrations with a correlation coefficient (r2) of 0.997 for both the drugs.Conclusion: The developed method was found to be simple, sensitive, selective, accurate, and repeatable for simultaneous analysis of BEC and SAL and can be adopted for routine analysis of these drugs in bulk and pharmaceutical dosage form.Â