MHD Boundary Layer Flow of a Nanofluid Past a Wedge

AbstractThis paper analyzes the steady laminar magnetohydrodynamic (MHD) flow, heat and mass transfer characteristics in a nanofluid over a wedge in the presence of a variable magnetic field. The governing nonlinear partial differential equations are transformed into a system of ordinary differential equations using similarity variables and then solved numerically by using spectral quasi linearization method (SQLM). The present numerical results are validated by favourable comparisons with previously published ones as the special cases of the present investigations. The effects of magnetic parameter, Falkner-Skan power-law parameter and the volume fraction parameter on the non-dimensional heat and mass transfer rates are presented graphically

Abnormal ossified structures around the hip joint and its clinical implications

Background: The hip joint is the body’s second largest weight-bearing joint forms a connection from the lower limb to the pelvic girdle. It is formed by an articulation between the pelvic acetabulum and the head of the femur. Ankylosis or fusion of the joint, ossification of the adjacent ligaments and calcific tendinitis of adjacent muscles can decrease the mobility of the joint. The study was undertaken to evaluate the incidence of abnormal ossified structures around the hip joint.Methods: This study was carried out on 228 dry human hip bones (right- 114 and left-114) and 228 dry human femur bones (right- 114 and left-114) irrespective of age and sex at Varun Arjun medical college-Banthra, UP, KMCT Medical College, Manassery-Calicut and Melaka Manipal Medical College-Manipal. All the hip and femur bones were macroscopically inspected for the abnormal ossified structures around the pelvic acetabulum and upper end of the femur. Photographs of the abnormal ossified structures were taken for proper documentation.Results: Very rare and unusual unilateral ossified and complete fused left hip joint was noted (0.43%). Unilateral ossified acetabular labrum with ossified transverse acetabular ligament was noted in seven right hip bones (3.07%). Unusual ossified fibrous capsule on the posterior aspect of neck of femur was noted in 4 left sided femur bones (1.75%). Unusual unilateral ossified deposits near the greater trochanter and intertrochanteric line of femur was noted in nine left sided femur bones (3.94%).Conclusions: Anatomical knowledge of ankylosis of hip joint, ossification of the ligaments and muscles tendons around the hip joint as found in the present study made this study unique such abnormal ossifications may be helpful for clinicians, radiologists and surgeons for differential diagnosis and can be implicated in the development of innovative treatments of hip joint and hip pains

Anatomical and congenital variations of human dry sternum bone: its embryogenesis and clinical implications

Background: The sternum is one of the skeleton parts with frequently detected variation in cross-sectional images or autopsy series. The anatomical or congenital variations of the sternum in the anterior chest wall may involve malignancies, injuries or severe traumas. The aim of the study was undertaken to evaluate the incidence of anatomical and congenital variations of human dry sternum bones.Methods: This study was carried out on 120 dry human sternum bones irrespective of age and sex at Varun Arjun medical college- Banthra, UP, KMCT Medical College, Manassery-Calicut and Melaka Manipal Medical College-Manipal. All the sternum bones were macroscopically inspected for the anatomical and congenital variations of human dry sternum bones. Photographs of the anatomical and congenital variations were taken for proper documentation.Results: Complete sternal foramina in the body of the sternum were noted in 9 bones (7.5%), with an average vertical diameter of 17mm and transverse diameter of 16mm (The highest vertical diameter of 19mm and transverse diameter of 17mm was noted); Incomplete sternal foramina in the body of the sternum were noted in 4 bones (3.3%);Complete sternal foramina in the xiphoid process of the sternum were noted in 7 bones (5.8%) with an average vertical diameter of 6mm and transverse diameter of 8mm; Unusual complete sternal foramina in the body and incomplete sternal foramina in the xiphoid process of the sternum were noted in 8 bones (6.6%); Very rare longer xiphoid process (7.3 cm) with complete sternal foramina was noted in 7 bone (5.8%); Unusual Longer xiphoid process with an average length of 6.7cm with sharp bifid ends was noted in 8 bones (6.6%).Conclusions: The knowledge of existence of anatomical variants and congenital foramina of sternum and xiphoid process found in our study is essential, especially for bone marrow sampling, radiology (X - ray, CT, MRI, and USG) reporting, pathology autopsy and forensic medicine post-mortem reporting and patoacupuncture practice to avoid complications during various surgical procedures

Asymmetric Surface Brightness Structure of Caustic Crossing Arc in SDSS J1226+2152: A Case for Dark Matter Substructure

We study the highly magnified arc SGAS J122651.3+215220 caused by a star-forming galaxy at $z_s=2.93$ crossing the lensing caustic cast by the galaxy cluster SDSS J1226+2152 ($z_l=0.43$), using Hubble Space Telescope observations. We report in the arc several asymmetric surface brightness features whose angular separations are a fraction of an arcsecond from the lensing critical curve and appear to be highly but unequally magnified image pairs of underlying compact sources, with one brightest pair having clear asymmetry consistently across four filters. One explanation of unequal magnification is microlensing by intracluster stars, which induces independent flux variations in the images of individual or groups of source stars in the lensed galaxy. For a second possibility, intracluster dark matter subhalos invisible to telescopes effectively perturb lensing magnifications near the critical curve and give rise to persistently unequal image pairs. Our modeling suggests, at least for the most prominent identified image pair, that the microlensing hypothesis is in tension with the absence of notable asymmetry variation over a six-year baseline, while subhalos of $\sim 10^6$--$10^8\,M_\odot$ anticipated from structure formation with Cold Dark Matter typically produce stationary and sizable asymmetries. We judge that observations at additional times and more precise lens models are necessary to stringently constrain temporal variability and robustly distinguish between the two explanations. The arc under this study is a scheduled target of a Director's Discretionary Early Release Science program of the James Webb Space Telescope, which will provide deep images and a high-resolution view with integral field spectroscopy.Comment: New version accepted by MNRAS; 18 pages including references and appendices, 13 figures and 4 tables; major revision of Sec. 3.2 and Figure 4 presenting improved data analysis; original conclusion strengthened

Simulation of Droplet Formation, Ejection, Spread, and Preliminary Designof Nozzle for Direct Ceramic Inkjet Printing

Recent advances in drop-on-demand (DOD)-type inkjet printing techniques have increasedresearch activities in the area of direct ceramic inkjet printing. In an attempt to develop a ceramicinkjet printer for the manufacture of ceramic components with their sizes in micro scale, theformation of ceramic ink droplet (ethyl alcohol loaded with different volume fractions of aluminaparticles) and its spread from a reservoir using piezoelectric actuation are simulated. The propertiesof the ceramic ink are taken from the data reported in literature. The simulations were performedwith computational fluid dynamics software (CFD-ACE+), CFDRC. This study gives details ofthe interaction among different physical phenomena that contribute to the droplet formation andejection process. The results from this study are being used for a preliminary design of nozzleand for the preparation of ceramic inks to achieve the desired droplet characteristics

Entropy driven spontaneous formation of highly porous films from polymer-nanoparticle composites

doi: 10.1088/0957-4484/20/42/425602Nanoporous materials have become indispensable in many fields ranging from photonics, catalysis and semiconductor processing to biosensor infrastructure. Rapid and energy efficient process fabrication of these materials is, however, nontrivial. In this communication, we describe a simple method for the rapid fabrication of these materials from colloidal dispersions of Polymethyl Silsesquioxane nanoparticles. Nanoparticle-polymer composites above the decomposition temperature of the polymer are examined and the entropic gain experienced by the nanoparticles in this rubric is harnessed to fabricate novel highly porous films composed of nanoparticles. Optically smooth, hydrophobic films with low refractive indices (as low as 1.048) and high surface areas (as high as 1325 m2 g−1) have been achieved with this approach. In this communication we address the behavior of such systems that are both temperature and substrate surface energy dependent. The method is applicable, in principle, to a variety of nanoparticle-polymer systems to fabricate custom nanoporous materials.We gratefully acknowledge the financial support from National Institute of Health (Award number 2-U42RR014821) and the US army

Development and characterization of fluorescent dye-doped nanoparticles with enhanced fluorescence intensity and photostability [abstract]

Nanoscience Poster SessionWe report the development of fluorescent dye doped organosilicate nanoparticles (DOSNPs) synthesized from poly-methylsilsesquioxane(PMSSQ), resulting in high fluorescence intensity and excellent photostability. The surface modified DOSNPs have hydrophilic surfaces and hydrophobic cores that enhance water-solubility and protect the dyes from oxidation and phtobleaching. These DOSNPs show superior properties over conventional dyes such as high fluorescence intensity due to approximately hundred dye molecules per particle and photostability demonstrating 7% and 76% fluorescence decay under continuous excitation for rhodamine 6G (R6G) DOSNP and R6G molecules, respectively, and have potential to be used in many areas, for example, imaging, sensing and solar cells. DOSNPs, when conjugated to anti-fibronectin antibodies, increased sensitivity of detection by approximately 600 fold relative to individual dye molecules conjugated to antibody. The DOSNPs are being applied to the development of diagnostic devices to be used in the detection of drugs, metabolites and pathogens