Microwave characterization of Pb<Subscript>1−x</Subscript>Ca<Subscript>x</Subscript>Fe<Subscript>0.5</Subscript>Nb<Subscript>0.5</Subscript>O<Subscript>3</Subscript> multiferroics at X-band

The microwave characteristics of Pb_1?x Ca _x Fe_0.5Nb_0.5O₃ multiferroics (x = 0.0, 0.4, 0.45, 0.5, 0.55, 0.6), have been investigated as a function of frequency and substitution. The results depict ?13.99 dB reflection loss at 11.65 GHz in composition x = 0.6. Microwave absorption is enhanced with substitution of Ca²⁺ ions and undoped composition 0.0 behaves as electromagnetic shield. The model governing microwave absorption is discussed and different compositions for electromagnetic applications have been suggested.     

Design,synthesis and SAR of antitubercular benzylpiperazine ureas

Molecular Diversity - N-furfuryl piperazine ureas disclosed by scientists at GSK Tres Cantos were chosen as antimycobacterial hits from a phenotypic whole-cell screen. Bioisosteric replacement of...     

Computing Vertex Connectivity: New Bounds from Old Techniques

The vertex connectivity κ of a graph is the smallest number of vertices whose deletion separates the graph or makes it trivial. We present the fastest known deterministic algorithm for finding the vertex connectivity and a corresponding separator. The time for a digraph having n vertices and m edges is O(min{κ³ + n, κn}m); for an undirected graph the term m can be replaced by κn. A randomized algorithm finds κ with error probability 1/2 in time O(nm). If the vertices have nonnegative weights the weighted vertex connectivity is found in time O(κ₁nmlog(n²/m)) where κ₁ ≤ m/n is the unweighted vertex connectivity or in expected time O(nmlog(n²/m)) with error probability 1/2. The main algorithm combines two previous vertex connectivity algorithms and a generalization of the preflow-push algorithm of Hao and Orlin (1994, J. Algorithms17, 424–446) that computes edge connectivity.     

A Trimodal Closomer Drug‐Delivery System Tailored with Tracing and Targeting Capabilities

The construction and application of a unique monodisperse closomer drug‐delivery system (CDDS) integrating three different functionalities onto an icosahedral closo‐dodecaborane [B₁₂]^2? scaffold is described. Eleven B‐OH vertices of [closo‐B₁₂(OH)₁₂]^2? were used to attach eleven copies of the anticancer drug chlorambucil and the targeting vector glucosamine through a bifurcating lysine linker. The remaining twelfth vertex was used to attach a fluorescent imaging probe. The presence of multiple glucosamine units offered a monodisperse and highly water‐soluble CDDS with a high payload of therapeutic cargo. This array enhanced the penetration of the drug into cancer cells by exploiting the overexpression of GLUT‐1 receptors present on cancer cells. About 15‐fold enhancement in cytotoxicity was observed for CDDS‐1 against Jurkat cells, compared to CDDS‐2, which lacks the GLUT‐1 targeting glucosamine. A cytotoxicity comparison of CDDS‐1 against colorectal RKO cells and its GLUT‐1 knock‐out version confirmed that GLUT‐1 mediates endocytosis. Using fluorescent markers both CDDS‐1 and ‐2 were traced to the mitochondria, a novel target for alkylating agents.     

Velocity dispersion in an elastic plate with microstructure: effects of characteristic length in a couple stress model

Microstructural effects become important, when dimensions of the heterogeneous material are comparable to the length scale of microstructure and the state of stress needs to be defined in a non-local manner. Linear theory of elasticity, which is associated with the concept of homogeneity of material and local stresses, cannot describe the behavior of the materials with microstructures. In this study, Couple stress theory of elasticity has been employed to capture the size effects on the propagation of Lamb waves in an elastic plate with microstructure. Effects on the dispersion curves of Lamb waves are studied, when the characteristic length of the material is comparable to cell size. The governing equations of couple stress theory, involving stresses and couple stresses are solved to study the impact of different characteristic lengths, comparable with cell size. Since bone is a material with microstructure, so for numerical calculations and graphical representation of the results, the plate is considered to have mechanical properties typically used for bones.     

Fractional Boundary Value Problems with Integral Boundary Conditions via Topological Degree Method

This paper examines the existence and uniqueness of solutions for the fractional boundary value problems with integral boundary conditions. Banach’s contraction mapping principle and Schaefer’s fixed point theorem have been used besides topological technique of approximate solutions. An example is propounded to uphold our results.