A Review of HER4 (ErbB4) Kinase,Its Impact on Cancer,and Its Inhibitors

HER4 is a receptor tyrosine kinase that is required for the evolution of normal body systems such as cardiovascular, nervous, and endocrine systems, especially the mammary glands. It is activated through ligand binding and activates MAPKs and PI3K/AKT pathways. HER4 is commonly expressed in many human tissues, both adult and fetal. It is important to understand the role of HER4 in the treatment of many disorders. Many studies were also conducted on the role of HER4 in tumors and its tumor suppressor function. Mostly, overexpression of HER4 kinase results in cancer development. In the present article, we reviewed the structure, location, ligands, physiological functions of HER4, and its relationship to different cancer types. HER4 inhibitors reported mainly from 2016 to the present were reviewed as well.     

A Generalized Spatial Modulation System Using Massive MIMO Space Time Coding Antenna Grouping

Massive multiple input multiple output (MIMO), also known as a very large-scale MIMO, is an emerging technology in wireless communications that increases capacity compared to MIMO systems. The massive MIMO communication technique is currently forming a major part of ongoing research. The main issue for massive MIMO improvements depends on the number of transmitting antennas to increase the data rate and minimize bit error rate (BER). To enhance the data rate and BER, new coding and modulation techniques are required. In this paper, a generalized spatial modulation (GSM) with antenna grouping space time coding technique (STC) is proposed. The proposed GSM-STC technique is based on space time coding of two successive GSM-modulated data symbols on two subgroups of antennas to improve data rate and to minimize BER. Moreover, the proposed GSM-STC system can offer spatial diversity gains and can also increase the reliability of the wireless channel by providing replicas of the received signal. The simulation results show that GSM-STC achieves better performance compared to conventional GSM techniques in terms of data rate and BER, leading to good potential for massive MIMO by using subgroups of antennas.     

Polarographic behaviour of some p-nitrophenyl-diazo-aryl sulphides in aqueous buffered media

The polarographic behaviour of some p-nitrophenyl-diazo-aryl sulphides in 40% ethanolic aqueous buffers is reported and discussed. The mechanism of electrode processes corresponding to the observed cathodic waves is proposed and clarified by means of model compounds and identification of controlled potential electrolysis products.     

Glow discharge in microfluidic chips for visible analog computing

Here we present a novel visible analog computing approach for solving a wide class of shortest path problems. Using a microfluidic chip for computation, based on the lighting up of a glow discharge, the solution to maze search problems, the solution of a network shortest path and k-shortest paths problems and the practical application of finding the shortest paths between several landmarks from a street map are presented. The solution and visible display (in real time) for these problems shows only a small difference in practical problem solving time among problems with varying differences in size.     

Synthesis and Some Reactions of Quinoxalinecarboazides

Chlorination of ethyl(quinoxalin‐2(1H)one)‐3‐carboxylate 1 gave ethyl (2‐chloroquinoxaline)‐3‐carboxylate 2 ;thionation of 1 by P₂S₅ or 2 by thiourea yielded the same product 3 . Reaction of chloro compound 2 or thiocompound 3 with hydrazine hydrate gave pyrazolylquinoxaline 4 . The reaction of ester 1 with thiourea or hydrazine hydrate afforded pyrimido quinoxaline 5 or carbohydrazide 6 ; the reaction of 6 with carbon disulfide in basic medium followed by alkylation afforded oxadiazoloquinoxaline derivatives 7, 8a,b . Carboazide 9 was produced by reaction of 5 with nitrous acid. Compound 9 on heating in an inert solvent, with or without amines, in alcohols or hydrolysis in H₂O undergoes Curtius rearrangments to yield 10‐13 . Reaction of 13 with thiosemicarbazide gave triazoloquinoxaline 14 which on reaction with alkylhalides or hydrazine hydrate yielded 15a‐c while hydrolysis of 13 gave 3‐aminoquinoxalinone 16 which was used as an intermediate to produce 17‐20 .     

MHD of a fractional viscoelastic fluid in a circular tube

We investigate the effect of a transverse magnetic field on the unsteady flow of a generalized second grade fluid through a porous medium in a circular tube. Using fractional partial differential equations, we are able to describe the velocity and stress fields of the flow. We also obtain exact analytic solutions of these differential equations in terms of the Fox’s H-function.     

Magneto-thermoelastic problem in non-homogeneous isotropic cylinder

The present paper concerns the investigation of the stress, temperature and magnetic fields in an isotropic elastic cylinder in a primary magenetic field when the curved surface of the cylinder subject to certain boundary conditions.The system of fundamental equations is solved by means of a finite difference method and the numerical calculations are carried out for the temperature, the components of displacement and the components of stresses with time and through the thickness of the cylinder. The results indicate that the effects of inhomogeneity and magnetic field are very pronounced.     

Synthesis of 3,4-Biheterylthieno[2,3-b]-thiophenes. Part I: Synthesis of 3,4-Bi(1′,3′,4′-thiadiazolyl-, s-triazolyl-,1′,3′,4′-thiadiazinyl-, 1′,3′,4′-triazinyl-, thiazolyl-, 1′,3′-thiazinyl- and primidinyl)-thieno[2,3-b]thiophenes

3,4-Diamino-2,5-dicarbethoxythieno[2,3-b]thiophene ( 1 ) was allowed to react with NaNO 2 and active methylenes to afford the corresponding azo compounds 2a-c . Hydrazonyl chloride 2a was treated with carbon disulfide, phenyl isothiocyanate, benzonitrile, benzyl cyanide, malononitrile, benzalaniline, ethyl mercaptoacetate, and ethyl glycinate to give 1,3,4-thiadiazolyl-, s-triazolyl-, 1,3,4-thiadiazinyl-, 1,3,4-triazinylthieno[2,3-b]thiophenes 3-6 respectively. The reaction of 2b,c with urea, thiourea, and guanidine afforded pyrimidinyl- and thiazinylazothieno [2,3-b]thiophenes 7-10 respectively. Bithiazolylthieno[2,3-b]thiophenes 11 and 13 were synthesized by treating compound 1 with CS 2 along with halo compounds. The addition of S,S-, N,S-, and N,O-acetals to the Schiff base 14 afforded compounds 15-17 respectively.     

NOVEL SUPRAMOLECULAR DERIVATIVES CONTAINING TWO R3Sn+ (R = Me,n-Bu,or Ph) CONNECTING UNITS: THE FORMATION OF NOVEL HOST–GUEST SYSTEMS BY THE FACILE ENCAPSULATION OF GUEST THIOPHENE COMPOUNDS

New supramolecular complexes [(Me ₃ Sn)(Ph ₃ Sn) ₂ Fe(CN) ₆ ] (I) and [(n-Bu ₃ Sn)(Ph ₃ Sn) ₂ Fe(CN) ₆ ] (II) are readily accessible by straightforward self-assembly of [Fe(CN) ₆ ] ^3? and hydrated R ₃ Sn⁺/R′ ₃ Sn ⁺ ions (R = Ph, and R′ = Me or n-Bu). The structural characterization of (I) and (II) is compared with well-documented supramolecular complex containing only Ph ₃ Sn ⁺ unit, [(Ph ₃ Sn) ₃ Fe(CN) ₆ ]. These novel compounds have wide internal cavities capable of encapsulating voluminous organic compounds, and they behave as host acceptors forming charge transfer complexes (CTC). Thiophene compounds acting as guest donor species are encapsulated within the cavities of the three-dimensional (3D) supramolecular hosts. The structure and physical properties of these hosts and host–guest systems were studied by X-ray powder diffraction, IR, UV/Vis., and magnetic measurements.