Secure and Robust Error Correction for Physical Unclonable Functions

Editor's note:Physical unclonable functions (PUFs) offer a promising mechanism that can be used in many security, protection, and digital rights management applications. One key issue is the stability of PUF responses that is often addressed by error correction codes. The authors propose a new syndrome coding scheme that limits the amount of leaked information by the PUF error-correcting codes.—Farinaz Koushanfar, Rice University     

Enhancement of bending strain tolerance and current carrying property of MgB2 based multifilamentary wires

The effect of bending strain on current carrying capacity of MgB₂ multifilamentary wires was studied with 4, 8 and 16 multifilamentary wires. The critical current density (J_C) of straight wires and bent wires with 5, 10, and 15 cm diameter was measured. Both annealed & bent and bent & annealed wires were used for measurement. The J_C of annealed & bent wires were found to decrease with decrease in bent diameter and the rate of degradation of J_C decreased with increasing number of filaments, while bent & annealed wires almost retained its J_C at all diameters studied.     

Polyhydroxy propionate-co-hydroxy dodecanoate-co-hydroxy octadecanoate for in vitro cell culture

This study is novel to report the utilization of molasses for the production of polyhydroxy propionate-co-hydroxy dodecanoate-co-hydroxy octadecanoate from Pseudomonas sp. LDC-5 as prospective biomaterial. Thermal analysis revealed its potential for thermal permanence and melt processing. 3T3 fibroblasts were cultured on these different scaffolds and their proliferation was compared. Giemsa and acridine orange/ethidium bromide staining revealed that there was no distinct change in morphology. Polyhydroxyalkanoate:poly ethylene glycol blend was found to be the most promising for extracellular matrix secretion, a key thrust function of 3D culture. Lactate dehydrogenase assay indicated the membrane integrity. DNA fragmentation analysis showed that the scaffold did not damage DNA. Thus the prepared scaffold can serve as a promising biomaterial.     

Influence of Equimolar Concentration on Structural and Optical Properties of Binary Selenides Nanoparticles

Nanoparticles of PbSe, Cu₂Se, and CdSe are prepared for two equimolar concentrations (0.05 M and 0.1 M) by precipitation method at 130°C. The obtained nanoparticles were characterized by x-ray diffraction, Fourier transform infrared spectroscopy, scanning electron microscopy, and UV-visible analysis to study the structural, morphological, and optical properties and are discussed in detail.     

Activating the community for nutritional improvement

This presentation provides information on community-oriented action research conducted under the leadership of Dr. Rajammal P. Devadas, the recipient of the IUNS International Nutrition Award for 2001. Educating, activating, and energizing the community with empowerment have been the focus of the action-oriented research. In the four decades of work presented, massive efforts have been made in the areas of infant and preschool child nutrition; nutritious noon meal programs for children; integration of nutrition, health, and sanitation concepts in the primary school curriculum; use of local foods to eradicate malnutrition; introduction of novel and underexploited foods; food-based approaches to overcome micronutrient malnutrition; equipping women for food and nutrition security; and nutrition education. These efforts have been activated through development of relevant food and educational materials, their introduction to the community, impact evaluation, follow-up, and implementation of the concepts in relevant national programs with massive training efforts. Many of the efforts outlined have formed the basis for regional and nationwide nutrition intervention strategies. The experiences gained and training efforts developed have gone beyond the country-level exposure to training and equipping nutrition workers in other countries.     

Concrete made from ceramic industry waste: Durability properties

Concrete which contains waste products as aggregate is called ‘Green’ concrete. Use of hazardous waste in concrete-making will lead to green environment and sustainable concrete technology and so such concrete can also be called as ‘Green’ concrete. Concrete made with ceramic electrical insulator waste as coarse aggregate shows good workability, compressive, tensile and flexural strengths and modulus of elasticity. Further, study of its durability will ensure greater reliability in its usage. Permeation characters are used widely to quantify durability properties of concrete. This paper presents an experimental investigation on the permeation characteristics [volume of voids and water absorption (ASTM C642-06), chloride penetration (ASTM C1202-10), and sorption] of concrete with ceramic electrical insulator waste coarse aggregate (hereafter it is called recycled aggregate concrete) of six different water–cement ratios in comparison with those of corresponding conventional concrete mixes. From the results it has been observed that there is no significant change in the basic trend of permeation characteristics of this recycled aggregate concrete when compared to the conventional concrete. This recycled aggregate concrete possesses higher permeation characteristic values than those of conventional concrete. These values decrease with decrease in water–cement ratio for both the recycled aggregate concrete and the conventional concrete.     

Combined addition of nano diamond and nano SiO2, an effective method to improve the in-field critical current density of MgB2 superconductor

MgB₂ bulk samples added with nano SiO₂ and/or nano diamond were prepared by powder-in-sealed-tube (PIST) method and the effects of addition on structural and superconducting properties were studied. X-ray diffraction (XRD) analysis revealed that the addition caused systematic reduction in ‘a’ lattice parameter due to the substitution of C atoms at B sites and the strain caused by reacted intragrain nano particles of Mg₂Si as evinced by transmission electron microscope image. Scanning electron microscopy images showed distinct microstructural variations with SiO₂/diamond addition. It was evident from DC magnetization measurements that the in-field critical current density [J_C(H)] of doped samples did not fall drastically like the undoped sample. Among the doped samples the J_C(H) of co-doped samples were significantly higher and the best co-doped sample yielded a J_C, an order of magnitude more than the undoped one at 5 K and 8 T.     

Investigation of the selective catalytic reduction of NO by NH3 on Fe-ZSM5 monolith catalysts

Photocatalytic nitric oxide (NO) decomposition and reduction reactions, using carbon monoxide (CO) as a reducing gas, have been investigated over Degussa P25 titanium dioxide photocatalysts, using a continuous flow reactor. The effects of thermal pretreatment temperature and reaction gas composition on the activity and selectivity of the decomposition and reduction reactions have been evaluated. Prepared materials were characterised by X-ray diffraction (XRD), N₂ physisorption, transmission electron microscopy (TEM) and differential scanning calorimetry (DSC) and findings from these techniques were used to explain the observed photocatalytic properties. XRD and TEM results indicated that for the pretreatment temperatures used (70, 120, 200, 450 and 600 °C) there was no appreciable change in the phase composition and the original composition of ca. 77 vol.% anatase and 23 vol.% rutile was maintained even after treatment at 600 °C. It was found that the photocatalytic activity for both the decomposition and reduction reactions decreased with increasing pretreatment temperature. This was attributed to the removal of surface hydroxyl species that act as active sites for reaction. For the decomposition reactions the only products observed were nitrogen and nitrous oxide and the selectivity for nitrogen formation remained constant (ca. 23%) regardless of the pretreatment temperature. The presence of CO in the reaction gas had a dramatic effect on the selectivity of the reactions with nitrogen selectivities as high as 65% being observed. It was found that as the CO/NO ratio increased the selectivity for nitrogen formation increased.