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Kinsuk Das,1 AP Madhusoodan,1 Bhabesh Mili,1 Ajay Kumar,2 AC Saxena,3 Kuldeep Kumar,1 Mihir Sarkar,1 Praveen Singh,4 Sameer Srivastava,5 Sadhan Bag1 1Division of Physiology and Climatology, 2Biochemistry and Food Science Section, 3Division of Surgery, 4Biophysics, Electron Microscopy and Instrumentation Section, 5Division of Veterinary Biotechnology, Indian Council of Agricultural Research – Indian Veterinary Research Institute, Izatnagar, Bareilly, Uttar Pradesh, India Abstract: In the field of regenerative medicine, numerous potential applications of mesenchymal stem cells (MSCs) can be envisaged, due to their ability to differentiate into a range of tissues on the basis of the substrate on which they grow. With the advances in nanotechnology, carbon nanotubes (CNTs) have been widely explored for use as cell culture substrate in tissue engineering applications. In this study, canine bone marrow-derived MSCs were considered as the cellular model for an in vitro study to elucidate the collective cellular processes, using three different varieties of thin films of functionalized carbon nanotubes (COOH-single-walled CNTs [SWCNTs], COOH-multiwalled CNTs [MWCNTs] and polyethylene glycol [PEG]-SWCNTs), which were spray dried onto preheated cover slips. Cells spread out better on the CNT films, resulting in higher cell surface area and occurrence of filopodia, with parallel orientation of stress fiber bundles. Canine MSCs proliferated at a slower rate on all types of CNT substrates compared to the control, but no decline in cell number was noticed during the study period. Expression of apoptosis-associated genes decreased on the CNT substrates as time progressed. On flow cytometry after AnnexinV-fluorescein isothiocyanate/propidium iodide (PI) staining, total number of apoptotic and necrotic cells remained lower in COOH-functionalized films compared to PEG-functionalized ones. Collectively, these results indicate that COOH-MWCNT substrate provided an environment of low cytotoxicity. Canine MSCs were further induced to differentiate along osteogenic, chondrogenic, and neuronal lineages by culturing under specific differentiation conditions. The cytochemical and immunocytochemical staining results, as well as the expression of the bone marker genes, led us to hypothesize that the COOH-MWCNT substrate acted as a better cue, accelerating the osteogenic differentiation process. However, while chondrogenesis was promoted by COOH-SWCNT, neuronal differentiation was promoted by both COOH-SWNCT and COOH-MWCNT. Taken together, these findings suggest that COOH-functionalized CNTs represent a promising scaffold component for future utilization in the selective differentiation of canine MSCs in regenerative medicine. Keywords: canine MSCs, CNT films, cellular behavior, cytocompatibility, differentiation

The purpose is to compare CT-based dosimetry with International Commission on Radiation Units and Measurements (ICRU 38) bladder and rectum reference points in patients of carcinoma of uterine cervix treated with intracavitary brachytherapy (ICA). Twenty-two consecutive patients were evaluated. Orthogonal radiographs and CT images were acquired and transferred to PLATO planning system. Bladder and rectal reference points were identified according to ICRU 38 recommendations. Dosimetry was carried out based on Manchester system. Patient treatment was done using 192 Iridium high dose rate (HDR) remote after-loading machine based on the conventional radiograph-based dosimetry. ICRU rectal and bladder point doses from the radiograph plans were compared with D 2 , dose received by 2 cm 3 of the organ receiving maximum dose from CT plan. V 2 , volume of organ receiving dose more than the ICRU reference point, was evaluated. The mean (±standard deviation) volume of rectum and bladder was 60 (±28) cm 3 and 138 (±41) cm 3 respectively. The mean reference volume in radiograph and CT plan was 105 (±7) cm 3 and 107 (±7) cm 3 respectively. It was found that 6 (±4) cm3 of rectum and 16 (±10) cm 3 of bladder received dose more than the prescription dose. V2 of rectum and bladder was 7 (±1.7) cm 3 and 20.8 (±6) cm 3 respectively. Mean D 2 of rectum and bladder was found to be 1.11 (±0.2) and 1.56 (±0.6) times the mean ICRU reference points respectively. This dosimteric study suggests that comparison of orthogonal X-ray-based and CT-based HDR ICA planning is feasible. ICRU rectal point dose correlates well with maximum rectal dose, while ICRU bladder point underestimates the maximum bladder dose.

Integrated PET/CT has emerged as an integral component of oncology management because of its unique potential of providing both functional and morphological images in a single imaging session. In this work, performance of the ′bismuth germinate (BGO) crystal′-based PET of a newly installed Discovery ST PET/CT was evaluated in 2D and 3D mode for whole-body scanning using National Electrical Manufacturers Association (NEMA) NU 2-2001 protocol and the recommended phantoms. During the entire measurements, the system operates with an energy window of 375-650 keV and 11.7 ns coincidence time window. The set of tests performed were spatial resolution, sensitivity, scatter fraction (SF) and counting rate performance. The average transaxial and axial spatial resolution measured as full width at half maximum (FWHM) of the point spread function at 1 cm (and 10 cm) off-axis was 0.632 (0.691) and 0.491 (0.653) cm in 2D and 0.646 (0.682) and 0.54 (0.601) cm in 3D respectively. The average sensitivity for the two radial positions ( R = 0 cm and R = 10 cm) was 2.56 (2.63) cps/kBq in 2D and 11.85 (12.14) cps/kBq in 3D. The average scatter fraction was 19.79% in 2D and 46.19% in 3D. The peak noise equivalent counting rate (NECR) evaluated with single random subtraction was 89.41 kcps at 49 kBq/cc in 2D and 60 kcps at 12 kBq/cc in 3D acquisition mode. The NECR with delayed random subtraction was 61.47 kcps at 40.67 kBq/cc in 2D and 45.57 kcps at 16.45 kBq/cc in 3D. The performance of the PET scanner was satisfactory within the manufacturer-specified limits. The test result of PET shows excellent system sensitivity with relatively uniform resolution throughout the FOV, making this scanner highly suitable for whole-body studies.

A case of Broncho Pulmonary Aspergillosis with Aspergillus Sinusitis was diagnosed in a nine year old boy after clinical and immunological investigations. He responded well after treatment with steroid and itraconazol.

Human skin tribology involves the study of friction behaviour of skin, with other materials in contact. Numerous studies have been conducted based both on the simulations and experimentations for the tribological investigations. Present study reports key experimental findings post year 2000 in which human skin (in vivo) is taken as test specimen. This review study highlights the latest technologies and trends that is in practice for tribological investigations on the human skin. For the selection of articles, the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) technique is adapted. Articles were screened out using various inclusion and exclusion criteria. Classifications were made based on the site of investigations viz. fingertip (22%), finger pad (36%), volar forearm (32%), and other regions (10%) as the anatomical regions. Study concludes that the maximum investigations have been performed on fabric/ textile followed by polymers, metals, plastics, and many others. Shearing has come up as the prominent factor for the erosion of soft surfaces. Study concludes the stick- slip friction to be the foremost contributor to the adhesion friction. [ABSTRACT FROM AUTHOR]

We report on electron emission and defect formation in the interaction between slow (v~;0.3 vBohr) highly charged ions (SHCI) with insulating (type IIa) and semiconducting (type IIb) diamonds. Electron emission induced by 31Pq+ (q=5 to 13), and 136Xeq+ (q=34 to 44) with kinetic energies of 9 kVxq increase linearly with the ion charge states, reaching over 100 electrons per ion for high xenon charge states without surface passivation of the diamond with hydrogen. Yields from both diamond types are up to a factor of two higher then from reference metal surfaces. Crater like defects with diameters of 25 to 40 nm are formed by the impact of single Xe44+ ions. High secondary electron yields and single ion induced defects enable the formation of single dopant arrays on diamond surfaces.

Direct numerical simulations of viscoelastic, subdiffusive, and plane Poiseuille flow, representing thick polymer solutions including polymer melts, flows of liquid crystals, as well as biological flow such as mucus, are reported. The stress strain equation is fundamentally derived by relating the timescale exponent at the microscale ( t α , with 0 < α ≤ 1) with the fractional order of the time derivative, α, of the corresponding non-linear equation in the continuum. The resultant stress constitutive equation is the fractional variant of the well-known upper convected Maxwell equation. In order to quantify the formation of spatiotemporal macrostructures (or the non-homogeneous regions of high viscosity at moderate to high fluid inertia), the space of symmetric positive definite polymer conformation tensors is visualized using a Riemannian metric along with its three scalar invariants. Numerical simulations of the channel flow, in the regime of low to moderate Reynolds number and low Weissenberg number, effectively capture these flow-structures by providing (i) a better resolution of the instantaneous regions of elastic shocks (which are the alternating regions of expanded and compressed polymer volume, in comparison with the volume of the mean conformation tensor), and (ii) a better resolution to detect neighborhoods where the mean conformation tensor tends to be significantly different in comparison to the instantaneous conformation tensor, thereby corroborating the experimentally observed flow-instability transition of subdiffusive flows. Finally, the strength of the subdiffusive flow model and the invariant theory is highlighted through an application of an electrohydrodynamic micropump. [ABSTRACT FROM AUTHOR]

In this paper, the performance of improved modified switching (IMS) scheme for the hybrid FSO/RF system is evaluated under the mixture composite irradiance channel fading model with pointing errors. Here, the combined effect of atmospheric turbulence and pointing error in optical domain is modelled by the mixture gamma (MG) distribution, which is a more accurate model in comparison to "K" and "Gamma" distributions. Further, in RF communication the fading channel is modeled as Nakagami "m" distribution. The average data rate, outage probability and error performances of the hybrid FSO/RF system under consideration are evaluated and compared with those of existing hard switching scheme (HS). For a meaningful comparison, IMS and HS schemes are considered in two different scenarios. Firstly, the average data rate of both the switching schemes are made identical by an appropriate choice of RF/FSO SNR thresholds. The two schemes are then compared on the basis of the other two performance metrics i.e. outage and BER. Secondly, the outage probabilities are made identical, and comparison is made on the basis of BER and average data rate. [ABSTRACT FROM AUTHOR]