Field trials and test results of portable DVB-T systems with transmit delay diversity

This paper describes work carried out by Brunel University and Broadreach Systems (UK) to quantify the advantages that can be achieved if Transmit Diversity is applied to systems employing the DVB standard. The techniques investigated can be applied to standard receiver equipment without modification. An extensive and carefully planned field trial was performed during the winter of 2007/2008 in Uxbridge (UK) to validate predictions from theoretical modeling and laboratory simulations. The transmissions were performed in the 730 MHz frequency band with a DVB-T transmitter and a mean power of 18.4dBW. Transmit delay diversity has been observed to deliver significant reception improvement in automotive and indoor- non line of sight situations

Laboratory measurement campaign of DVB-T signal with transmit delay diversity

The requirements for future DVB-T/H networks demand that broadcasters design and deploy networks that provide ubiquitous reception in challenging indoors and other obstructed situations. It is essential that such networks are designed cost-effectively and with minimized environmental impact. The EC funded project PLUTO has since its start in 2006 explored the use of diversity to improve coverage in these difficult situations. The purpose of this paper is to investigate the performance of Transmit Delay Diversity (DD) with two antennas to improve the reception of DVB-T/H systems operating in different realistic propagation conditions through a series of tests using a SPIRENT SR5500 dual channel emulator. The relationship between correlation coefficient between channels, receiver velocity and diversity gain is nvestigated. It is shown that transmit delay diversity significantly improves the quality of reception particularly in simulated fast fading mobile broadcasting applications. This paper documents research conducted by Brunel University and Broadreach Systems

Wireless structural health monitoring (SHM) system for damage detection using ultrasonic guided waveform response

This paper presents an improved version of a wireless device embedded with a smart PZT sensor to detect flaws and structural defects on selected investigated structure. Smart PZT sensors were used as an actuator and sensor, coupled with two XBee's and one signal generator IC chip. Programme execution on transmitting and receiving the ultrasonic guided wave via the PZT sensor had been written in MATLAB. The developed source code is basically to receive serial data from one Xbee to another remote Xbee attached to the investigated structural system. The refined waveform response is utilised for prognosis of the true structural status. The 4-mm simulated holed into one of the aluminium structural plate is benchmarked with its pristine condition in validating the effectiveness of the developed SHM wireless module. Results showed that the wave is more even in non-defected area and disrupted in affected area. Ultrasonic waves increase continuously for non-destructive evaluation and structural health monitoring in various structural applications because the guided wave can propagate long distances and reach difficult-to-access regions; for inspecting porous and some non-porous materials ultrasonic waves attenuate fast and are very useful. Recent advances in ultrasonic wave application model and results are discussed in this paper

Synthesis, characterization, anti-microbial and cytotoxic applications of zinc(II) complexes

ABSTRACT. In the present research, three zinc(II) complexes were synthesized using 3-(3-fluorophenyl)-2-methylacrylic acid (HL), 1,10-phenanthroline and 2,2'-pyridine as ligands. The composition, structural confirmation, coordination way of ligand and assignment of geometry to the complexes were made by different analytical tools like elemental analysis, FTIR and 1H-NMR. The ligand 3-(3-fluorophenyl)-2-methylacrylate appeared to coordinate the metal (Zn) atom via COO- moiety in all of the complexes (1-3) while 1,10-phenanthroline and 2,2'-pyridine co-ordinated to Zn(II) atom through N-donor sites in complexes 2 and 3, respectively. The complex 1 showed four while 2 and 3 showed six co-ordinated geometry. The synthesized complexes were evaluated for antimicrobial and cytotoxic activities. The obtained results showed that complexes are active against microbial agents and exhibited significant cytotoxicity.                     KEY WORDS: Co-coordination, Geometry, Zinc(II) complexes, Biological activity   Bull. Chem. Soc. Ethiop. 2021, 35(2), 287-299. DOI: https://dx.doi.org/10.4314/bcse.v35i2.

Conversion of fused knee following distal femur tumor surgery to total knee arthroplasty

Conversion of knee arthrodesis to total knee arthroplasty is a difficult procedure accompanied by many complications due to soft tissue and extensor mechanism contracture and bone defects. We report two cases of distal femur osteosarcoma that had been undergone wide resection arthrodesis initially. Arthrodesis was converted to total knee arthroplasty with hinged prosthesis after many years. We describe patients' history and outline their surgical therapy and prognosis. To the best of the authors' knowledge, few cases have been previously reported in the literature. © 2013, Iranian Red Crescent Medical Journal

CSNL: A cost-sensitive non-linear decision tree algorithm

This article presents a new decision tree learning algorithm called CSNL that induces Cost-Sensitive Non-Linear decision trees. The algorithm is based on the hypothesis that nonlinear decision nodes provide a better basis than axis-parallel decision nodes and utilizes discriminant analysis to construct nonlinear decision trees that take account of costs of misclassification. The performance of the algorithm is evaluated by applying it to seventeen datasets and the results are compared with those obtained by two well known cost-sensitive algorithms, ICET and MetaCost, which generate multiple trees to obtain some of the best results to date. The results show that CSNL performs at least as well, if not better than these algorithms, in more than twelve of the datasets and is considerably faster. The use of bagging with CSNL further enhances its performance showing the significant benefits of using nonlinear decision nodes. The performance of the algorithm is evaluated by applying it to seventeen data sets and the results are compared with those obtained by two well known cost-sensitive algorithms, ICET and MetaCost, which generate multiple trees to obtain some of the best results to date. The results show that CSNL performs at least as well, if not better than these algorithms, in more than twelve of the data sets and is considerably faster. The use of bagging with CSNL further enhances its performance showing the significant benefits of using non-linear decision nodes

Damage identification using wireless structural health monitoring system through smart sensor application

Delamination, disbanding, void, low impact resistance and visible internal damage are some of damages uniquely found in the structure. Any damage found on the structure require repair. The inspection need to be done to detect the damage on structure before the structure can be repaired. Non-Destructive Inspection (NDI) and Structural health monitoring (SHM) concept were used to detect flaws from structures. But the SHM differs from NDT which the system used to monitor the integrity of mechanical structures in a continuous and independent way. SHM helps to reduce financial cost for maintenance. SHM can monitor this situation in active and passive states, either by online or offline monitoring. The use of SHM is to augment the NDI application and not to replace it. This paper presents the damage identification technique by using the improved design of wireless structural health monitoring system. Smart PZT sensors were used as an actuator and receiver, coupled with two XBee’s and two Ardiuno as signal generator and signal receiver. Program execution on transmitting and receiving the ultrasonic guided wave via the PZT sensor had been written in Makerplot. The acquired results showed that the wave is more even in non-defected area and disrupted in affected area

Sirtuin Inhibition and Anti-Cancer Activities of Ethyl 2-benzimidazole-5-carboxylate Derivatives

New benzimidazoles were synthesized based on the previously identified sirtuin inhibitor BZD9L1. The compounds were screened for their sirtuin (SIRT1, SIRT2 and SIRT3) inhibitory activities. Compound BZD9Q1 was determined to be a pan-SIRT1–3 inhibitor. Furthermore, the proliferation of various cancer cells was inhibited by BZD9Q1. It was shown that BZD9Q1 elicits a cytostatic effect by inducing cell cycle arrest at the G2/M phase while also showing a prominent induction of apoptosis against oral cancer cells

Expression of sweet taste receptors of the T1R family in the intestinal tract and enteroendocrine cells.

Abstract The composition of the intestinal luminal content varies considerably with diet. It is important therefore that the intestinal epithelium senses and responds to these significant changes and regulates its functions accordingly. Although it is becoming evident that the gut epithelium senses and responds to luminal nutrients, little is known about the nature of the nutrient sensing molecule and the downstream cellular events. A prototype example is the modulation in the capacity of the gut to absorb monosaccharides via the intestinal luminal membrane Na + /glucose cotransporter, SGLT1. The experimental evidence suggests that luminal sugar is sensed by a glucose sensor residing on the luminal membrane of the gut epithelium and linked to a G-protein-coupled receptor, cAMP/PKA (protein kinase A) pathway, resulting ultimately in modulation of intestinal monosaccharide absorption. Here we report the expression, at mRNA and protein levels, of members of the T1R sweet taste receptors, and the α-subunit of the G-protein gustducin, in the small intestine and the enteroendocrine cell line, STC-1. In the small intestine, there is a highly coordinated expression of sweet taste receptors and gustducin, a G-protein implicated in intracellular taste signal transduction, throughout the gut. The potential involvement of these receptors in sugar sensing in the intestine will facilitate our understanding of intestinal nutrient sensing, with implications for better nutrition and health maintenance