Context Increased bone fragility and reduced energy absorption to fracture associated with type 2 diabetes (T2D) cannot be explained by bone mineral density alone. This study, for the first time reports on alterations in bone tissue's material properties obtained from individuals with diabetes and known fragility fracture status. Objective To investigate the role of T2D in altering biomechanical, microstructural and compositional properties of bone in individuals with fragility fracture. Design Femoral head bone tissue specimens were collected from patients who underwent replacement surgery for fragility hip fracture. Trabecular bone quality parameters were compared in samples of two groups: non-diabetic (n=40) and diabetic (n=30), with a mean duration of disease 7.5±2.8 years. Results No significant difference was observed in aBMD between the groups. Bone volume fraction (BV/TV) was lower in the diabetic group due to fewer and thinner trabeculae. The apparent-level toughness and post-yield energy were lower in those with diabetes. Tissue-level (nanoindentation) modulus and hardness were lower in this group. Compositional differences in diabetic group included lower mineral:matrix, wider mineral crystals, and bone collagen modifications - higher total fAGEs, higher non-enzymatic-cross-link-ratio (NE-xLR), and altered secondary structure (Amide bands). There was a strong inverse correlation between NE-xLR and post-yield-strain, fAGEs and post-yield energy, and, fAGEs and toughness. Conclusion Current study is novel in examining bone tissue in T2D following first hip fragility fracture. Our findings provide evidence of hyperglycemia’s detrimental effects on trabecular bone quality at multiple scales leading to lower energy absorption and toughness-indicative of increased propensity to bone fragility.

A significant seasonal variation in tuberculosis (TB) is observed in north India during 2006-2011, particularly in states like Himachal Pradesh, Haryana and Rajasthan. To quantify the seasonal variation, we measure average amplitude (peak to trough distance) across seasons in smear positive cases of TB and observe that it is maximum for Himachal Pradesh (40.01%) and minimum for Maharashtra (3.87%). In north India, smear positive cases peak in second quarter (April-June) and reach a trough in fourth quarter (October-December), however low seasonal variation is observed in southern region of the country. The significant correlations as 0.64 (p-value<0.001), 0.54 (p-value<0.01) and 0.42 (p-value<0.05) are observed between minimum temperature and seasonality of TB at lag-1 in north, central and northeast India respectively. However, in south India, this correlation is not significant.

In order to design a painless and mechanically durable micro syringe-needle system for biomedical applications, the study of insect stingers is of interest because of their elegant structures and functionalities. In the present work, the structure, mechanical properties and the mechanical behavior during insertion of wasp and honeybee stingers have been investigated. The non-invasive imaging tool, micro-computed tomography has been employed to reveal the 3D-structures of wasp and honeybee stingers. A quasi-static nanoindentation instrument was used to measure the nanomechanical properties. Both wasp and honeybee stingers have graded mechanical properties, decreasing along their longitudinal direction starting from the base. The computed tomography images and the measured material properties from nanoindentation were fed into a computational framework to determine the mechanical behavior of the stingers during penetration. The computation results predicted the penetration angle of +10° for the wasp stinger and −6° for the honeybee stinger, which mimics the practical insertion mechanism of both stingers. Based on this understanding, a wasp and honeybee stringer inspired micro syringe-needle design has also been proposed.

Long-term Type 2 Diabetes (T2D) affects the normal functioning of heart, kidneys, nerves, arteries, bones, and joints. The T2D gradually alters the intrinsic material properties, and structural integrity of the tissues and prolonged hyperglycemia causes chronic damages to these tissues quality. Clinically no such technique is available which can assess the altered tissues quality associated with T2D. In the present study, the microstructural characterization (surface morphology, surface roughness and density and calcium content), material characterization (modulus, hardness), and macromolecular characterization (disulfide bond content, protein content and its secondary structure) are investigated among healthy, diabetic controlled (DC) and uncontrolled diabetic (UC) group of fingernail plate. It is found that T2D has an adverse effect on the human fingernail plate quality. The parameters of nail plate quality are changing in a pattern among all the three groups. The properties mentioned above are degrading in DC group, but the degradation is even worst in the case of severity of T2D (UC group) as compared to the healthy group (Healthy

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