Investigation of natural radionuclides and radiation shielding potential of some commonly used building materials in Northwestern Nigeria.

This study assessed the gamma-ray shielding potential of clay, sand, gypsum and kaolin commonly used as a building material in Northwestern, Nigeria. The radiological status of the samples was first evaluated by determining the activity concentrations of U, Th and K using NaI (Tl) detector after which elemental composition and mass density were determined using Neutron Activation Analytical Technique. After which the mass attenuation coefficients (MAC), linear attenuation coefficients (LAC), half value layer (HVL), tenth value layer (TVL), and effective atomic number (Zeff) were determined experimentally and theoretically using standard point sources of Cs and Co photon peaks (0.

Residual LSTM-based short duration forecasting of polarization current for effective assessment of transformers insulation.

The empirical application of polarization and depolarization current (PDC) measurement of transformers facilitates the extraction of critical insulation-sensitive parameters. This technique, rooted in time-domain dielectric response analysis, forms the bedrock for parameterization and insulation modeling. However, the inherently time-consuming nature of polarization current measurements renders them susceptible to data corruption.

Bilateral Scapular Fracture due to an Epileptic Seizure: A Case Report.

Introduction: Bilateral scapular fractures are a very rare injury with only few cases reported in the literature. They are said to be consequence of a violent trauma to the upper part of shoulder or as a result of electrocution or seizures. Glenoid involvement or open scapular fractures are one of the indications for operative treatment in these injuries, in other cases, simple immobilization is sufficient to obtain good results.

Evaluation of radiological risk associated with local building materials commonly used in Northwestern Nigeria.

In this study, potential radiological risk due to the activity concentrations of primordial radionuclides (Ra, Th, and K) in commonly used local building materials (sand, clay, kaolin and gypsum) in Northwestern Nigeria were assessed using NaI (Tl) detector. The measured activity concentrations ranged from 47 to 63 Bq kg for Ra, 24-32 Bq kg for Th, and 219-257 Bq kg for K respectively. The mean values of Th, and K for all samples were below the respective world averages of 45 and 420 Bq kg with that of Ra for all the samples higher than the world average value of 32 Bq kg.

Performance of Microchannel Heat Sink Made of Silicon Material with the Two-Sided Wedge.

New designs of the microchannel with a two-sided wedge shape at the base were studied numerically. Five different wedge angles ranging from 3° to 15° were incorporated into the microchannel design. Simulation of this novel microchannel was carried out using Computational Fluid Dynamics (CFD).

Untangling Classification Methods for Melanoma Skin Cancer.

Skin cancer is the most common cancer in the USA, and it is a leading cause of death worldwide. Every year, more than five million patients are newly diagnosed in the USA. The deadliest and most serious form of skin cancer is called melanoma.

Mechanosensation and transduction in osteocytes.

The human skeleton is a miracle of engineering, combining both toughness and light weight. It does so because bones possess cellular mechanisms wherein external mechanical loads are sensed. These mechanical loads are transformed into biological signals, which ultimately direct bone formation and/or bone resorption.

Osteocyte morphology in human tibiae of different bone pathologies with different bone mineral density--is there a role for mechanosensing?

Matrix strains due to external loading are different in bones of different pathologies with different bone mineral density (BMD), and are likely sensed by the osteocytes, the putative bone mechanosensors. The mechanosensitivity of osteocytes appears to be strongly influenced by their morphology. In this study, we explored the possibility that osteocyte morphology might play a role in various bone pathologies with different BMD.

Osteocyte morphology in fibula and calvaria --- is there a role for mechanosensing?

Introduction: External mechanical forces on cells are known to influence cytoskeletal structure and thus cell shape. Mechanical loading in long bones is unidirectional along their long axes, whereas the calvariae are loaded at much lower amplitudes in different directions. We hypothesised that if osteocytes, the putative bone mechanosensors, can indeed sense matrix strains directly via their cytoskeleton, the 3D shape and the long axes of osteocytes in fibulae and calvariae will bear alignment to the different mechanical loading patterns in the two types of bone.

Paxillin localisation in osteocytes--is it determined by the direction of loading?

External mechanical loading of cells aligns cytoskeletal stress fibres in the direction of principle strains and localises paxillin to the mechanosensing region. If the osteocyte cell body can indeed directly sense matrix strains, then cytoskeletal alignment and distribution of paxillin in osteocytes in situ will bear alignment to the different mechanical loading patterns in fibulae and calvariae. We used confocal microscopy to visualise the immunofluorescence-labelled actin cytoskeleton in viable osteocytes and paxillin distribution in fixated osteocytes in situ.

Extracellular NO signalling from a mechanically stimulated osteocyte.

Bone remodelling is a dynamic process that requires the coordinated interaction of osteocytes, osteoblasts, and osteoclasts, collaborating in basic multicellular units (BMUs). Communication between these cells can be by extracellular soluble molecules as well as directly propagating intercellular signalling molecules. Key to the understanding of bone remodelling is osteocyte mechanosensing and chemical signalling to the surrounding cells, since osteocytes are believed to be the mechanosensors of bone, responding to mechanical stresses.

Bio imaging of intracellular NO production in single bone cells after mechanical stimulation.

Unlabelled: We show the intracellular upregulation of NO production after mechanical stimulation, an essential chemical signal in bone remodeling. This is done in real time using the fluorescent chromophore DAR-4M AM. Differences in cellular response to mechanical stimulation of different regions of a single cell were observed.