Concentration of the distance between points in the unit ball

We prove that in every finite dimensional normed space, for “most” pairs (x, y) of points in the unit ball, ║x − y║ is more than √2(1 − ε). As a consequence, we obtain a result proved by Bourgain, using QS-decomposition, that guarantees an exponentially large number of points in the unit ball any two of which are separated by more than √2(1 − ε)

Bi-algebras, generalised geometry and T-duality

A study of sigma models whose target space is a group G that admits a compatible Poisson structure is presented. The natural action of O(D,D;Z) on the generalised tangent bundle TG+T*G and a generalisation of the Courant bracket that appears are reviewed. This background provides a concrete example where the generalised geometry and doubled geometry descriptions are both well understood. Connections between the two formalisms are discussed and the world-sheet theory from Hamiltonian and Lagrangian perspectives is investigated. The comparisons between the approaches given by generalised geometry and doubled geometry suggest possible ways of generalising the analysis beyond the known examples.Comment: 43 page

Knowledge, Attitude and Practice on Blood Donation among Health Science Students in a University campus, South India

Background: The major part of demand for blood in India has been meeting through voluntary blood donations. The healthy, active and receptive huge student population is potential blood donors to meet safe blood requirements. However, there is a paucity of studies on awareness and attitude among health science students on voluntary blood donation. Objective: The objective of this study was to determine the knowledge and attitude about blood donation among health science students. Methods: A cross-sectional study was conducted among 410 health sciences students from different streams in a University campus of South India through a structured survey questionnaire in the year 2009. Results: The overall knowledge on blood donation was good, but majority (62%) of students never donated blood. Knowledge level was found highest among allied health science (53.1%) and lowest among pharmacy students (20.7%). ‘Feeling of medically unfit’ and ‘never thought of blood donation’ were the major reasons for not donating blood. A significant association was observed between different streams of students and levels of knowledge and attitude about blood donation. Conclusion: This study elicits the importance of adopting effective measures in our campuses to motivate about voluntary blood donation among students

Design and Measurements of a Five Independent Band Patch Antenna for Different Wireless Applications

This paper presents the design of a compact microstrip patch antenna with the ability of controlling the number of bands and the operating frequencies independently. Numerical equations are derived using a curve fitting technique to obtain the centre frequency of each band. The antenna comprises a main patch and four sub-patches fed by a 50 microstrip line. It is designed to generate up to five separate modes to cover the frequency range from 900MHz to 3GHz for the operation of wireless devices supporting multiple standards including Global System for Mobile communication (GSM900, 880-960 MHz), Digital Communication System (DCS1800, 1710-1880 MHz), Universal Mobile Telecommunication System (UMTS, 1920-2170 MHz), Wireless Local Area Network (WLAN, 2400-2483.5 MHz) and low band Worldwide Interoperability for Microwave Access (WIMAX, 2.5 to 2.8 GHz).NPL SMART chamber were supported by the Measurements for Innovators (MFI) program and the National Measurement Office, an Executive Agency of the Department for Business, Innovation and Skill

A reconfigurable CPW antenna for GPS, GSM and WLAN applications

Copyright @ 2011 IEEEMultiband reconfigurable antennas are receiving increasing importance in modern wireless communication systems supporting multiservice applications. The main advantage is the reduction in the size of wireless devices and allowing more space for other electronic components to be fitted. A widely tunable antenna using PIN switches was presented in [1]. Reconfigurable multiband antennas for wireless systems including satellite and terrestrial applications were reported in [2, 3]. This paper presents a new technique to electrically control the resonant frequencies by using a varactor diode. The antenna has an H-shape structure fed by a coplanar waveguide (CPW). It can generate and control up to three resonant frequencies to be used in GPS, GSM and Bluetooth/WLAN applications

Widely tunable multiband reconfigurable patch antenna for wireless applications

The official published version can be obtained from the link below - Copyright @ EuCAP 2010A design of a low profile reconfigurable microstrip patch antenna is presented. The antenna consists of four suppatches connected to one feed line, each sub-patch generates a single band. By placing a variable capacitor at the input of the sub-patches, the impedance matching frequency of the antenna can be tuned over a wide range starting from 0.92 GHz to 2.98 GHz with total tunability rang of 2060 MHz. The proposed antenna designed to operate in the Global System for Mobile communication (GSM900, 880-960 MHz)/ Digital Communication System (DCS1800, 1710-1880 MHz)/ Universal Mobile Telecommunication System (UMTS, 1920-2170 MHz)/ Wireless Local Area Network (WLAN, 2400-2483.5 MHz)/ and Worldwide Interoperability for Microwave Access (WiMAX, 2495-2700 MHz). The total size of the proposed antenna is 50 x 50 mm2 which is suitable for small wireless devices

A reconfigurable H-shape antenna for wireless applications

The official published version of this article can be obtained from the link below - Copyright @ EuCAP2010This paper presents a novel H-Shaped reconfigurable microstrip patch antenna fed by a Grounded Coplanar Waveguide (GCPW) for wireless applications. The uniqueness in the presented antenna design relies in the ability to select the number of operating frequencies electronically by using a varactor diode. The antenna structure consists of coplanar waveguide (CPW) input with an H-shape printed on a PCB and a varactor diode for reconfigurability. By electronically varying the value of the diode capacitance, the antenna can operate in a single band mode to cover Global Position System (GPS), a dual band mode to cover GPS and Global System for Mobile communications (GSM1900) or a three-band mode to cover GPS, GSM1900 and Bluetooth or Wireless Local Area Networks (WLAN)

A frequency reconfigurable multiband patch antenna for wireless applications

Copyright @ 2011 IEE

Strong Electron-Phonon Interaction and Colossal Magnetoresistance in EuTiO3_3

At low temperatures, EuTiO$_3$ system has very large resistivities and exhibits colossal magnetoresistance. Based on a first principle calculation and the dynamical mean-field theory for small polaron we have calculated the transport properties of EuTiO$_3$. It is found that due to electron-phonon interaction the conduction band may form a tiny subband which is close to the Fermi level. The tiny subband is responsible for the large resistivity. Besides, EuTiO$_3$ is a weak antiferromagnetic material and its magnetization would slightly shift the subband via exchange interaction between conduction electrons and magnetic atoms. Since the subband is close to the Fermi level, a slight shift of its position gives colossal magnetoresistance.Comment: 6 pages, 5 figure

P53 tumour-suppressor gene mutations are mainly localised on exon 7 in human primary and metastatic prostate cancer.

Mutations in the p53 tumour-suppressor gene are among the most common genetic alterations in human cancers. In the present study we analysed the mutations in the p53 tumor-suppressor gene in 25 primary and 20 metastatic human prostate cancer specimens. DNA extracted from the paraffin-embedded sections was amplified by hot-start polymerase chain reaction, and p53 gene mutations in the conserved mid-region (exons 4-9) were examined using single-strand conformation polymorphism (SSCP) analysis and immunohistochemistry. In the present study, we used a novel hot-start PCR-SSCP technique using DNA Taq polymerase antibody, which eliminates primer-dimers and non-specific products. Because of this new technique, the results of PCR-SSCP showed very high resolution. Polymerase chain reaction products were sequenced directly for point mutations for the p53 gene. Mutations were found in 2 out of 25 primary prostate cancers (8%) and 4 out of 20 metastatic cancers (20%). Mutations were observed exclusively in exon 7 and not in exons 4, 5, 6, 8 or 9. Nuclear accumulation of p53 protein, determined by immunohistochemistry, correlated with the degree of metastasis in prostatic cancer