Can diagnostic triage by general practitioners or rheumatology nurses improve the positive predictive value of referrals to early arthritis clinics?

Objectives: To determine whether diagnostic triage by general practitioners (GPs) or rheumatology nurses (RNs) can improve the positive predictive value of referrals to early arthritis clinics (EACs).

Methods: Four GPs and two RNs were trained in the assessment of early in?ammatory arthritis (IA) by four visits to an EAC supervised by hospital rheumatologists. Patients referred to one of three EACs were recruited for study and assessed independently by a GP, an RN and one of six rheumatologists. Each assessor was asked to record their clinical ?ndings and whether they considered the patient to have IA. Each was then asked to judge the appropriateness of the referral according to predetermined guidelines. The rheumatologists had been shown previously to have a satisfactory level of agreement in the assessment of IA.

Results: Ninety-six patients were approached and all consented to take part in the study. In 49 cases (51%), the rheumatologist judged that the patient had IA and that the referral was appropriate. The assessments of GPs and RNs were compared with those of the rheumatologists. Levels of agreement were measured using the kappa value, where 1.0 represents total unanimity. The kappa value was
0.77 for the GPs when compared with the rheumatologists and 0.79 for the RNs. Signi?cant stiffness in the morning or after rest and objective joint swelling were the most important clinical features enabling the GPs and RNs to discriminate between IA and non-IA conditions.

Conclusion: Diagnostic triage by GPs or RNs improved the positive predictive value of referrals to an EAC with a degree of accuracy approaching that of a group of experienced rheumatologists.

Hypoxia selects for androgen independent LNCaP cells with a more malignant geno- and phenotype.

Hypoxia confers resistance to common cancer therapies, however, it has also has been shown to result in genetic alterations which may allow a survival advantage and increase the tumorigenic properties of cancer cells. Additionally, it may exert a selection pressure, allowing expansion of tumor cells with a more aggressive phenotype. To further assess the role of hypoxia in malignant progression in prostate cancer we exposed human androgen dependent prostate cancer cells (LNCaP) to cycles of chronic hypoxia and isolated a subline, LNCaP-H1. This article describes the partial characterization of this cell line. The LNCaP-H1 subline showed altered growth characteristics and exhibited androgen independent growth both in vitro and in vivo. Furthermore, these cells were resistant to mitochondrial-mediated apoptosis, probably since the endogenous levels of Bax was lower and Bcl-2 higher than in the parental LNCaP cells. Microarray analysis revealed that a complex array of pathways had differential gene expression between the 2 cell lines, with LNCaP-H1 cells exhibiting a genetic profile which suggests that they may be more likely metastasize to distant organs, especially bone. This was supported by an in vitro invasion assay, and an in vivo metastasis study. This study shows that hypoxia can select for androgen independent prostate cancer cells which have a survival advantage and are more likely to invade and metastasize.

Sensitivity characteristics of inverse Class-E power amplifier

In this paper, an analysis is performed in order to determine the effects that variations in circuit component values, frequency, and duty cycle have on the performance of the newly introduced inverse Class-E amplifier. Analysis of the inverse Class-E amplifier under the generalized condition of arbitrary duty cycle is performed and it is shown that the inverse Class-E amplifier is reasonably tolerant to circuit parameter variations. When compared to the conventional Class-E amplifier the inverse Class-E amplifier offers the potential for high efficiency at increased output power as well as higher peak output power levels than are available with a conventional Class-E amplifier. Further the inverse Class-E amplifier provides more flexibility for deployment with a pulsewidth modulator as the means of producing full-carrier amplitude modulation (AM) due to its ability to operate to high AM modulation indices.

Coordination environment of [UO2Br4](2-) in ionic liquids and crystal structure of [Bmim](2)[UO2Br4]

The complex formed by the reaction of the uranyl ion, UO22+, with bromide ions in the ionic liquids 1-butyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide ([Bmiml[Tf2N]) and methyl-tributylammonium bis(trifluoromethylsulfonyl)imide ([MeBu3N][Tf2N]) has been investigated by UV-Vis and U L-III-edge EXAFS spectroscopy and compared to the crystal structure of [Bmim](2)[UO2Br4]. The solid state reveals a classical tetragonal bipyramid geometry for [UO2Br4](2-) with hydrogen bonds between the Bmim(+) and the coordinated bromides. The UV-Vis spectroscopy reveals the quantitative formation of [UO2Br4](2-) when a stoichiometric amount of bromide ions is added to UO2(CF3SO3)(2) in both Tf2N-based ionic liquids. The absorption spectrum also suggests a D-4h symmetry for [UO2Br4](2-) in ionic liquids, as previously observed for the [UO2Cl4](2-) congener. EXAFS analysis supports this conclusion and demonstrates that the [UO2Br4](2-) coordination polyhedron is maintained in the ionic liquids without any coordinating solvent or water molecules. The mean U-O and U-Br distances in the solutions, determined by EXAFS, are, respectively, 1.766(2) and 2.821(2)angstrom in [Bmim][Tf2N], and, respectively, 1.768(2) and 2.827(2) angstrom, in [MeBu3N][Tf2N]. Similar results are obtained in both ionic liquids indicating no significant influence of the ionic liquid cation either on the complexation reaction or on the structure of the uranyl species. (C) 2009 Elsevier Ltd. All rights reserved.

A New Restricted Full-Rank Single-Symbol Decodable Design for Four Transmit Antennas

Recently, a single-symbol decodable transmit strategy based on preprocessing at the transmitter has been introduced to decouple the quasi-orthogonal space-time block codes (QOSTBC) with reduced complexity at the receiver [9]. Unfortunately, it does not achieve full diversity, thus suffering from significant performance loss. To tackle this problem, we propose a full diversity scheme with four transmit antennas in this letter. The proposed code is based on a class of restricted full-rank single-symbol decodable design (RFSDD) and has many similar characteristics as the coordinate interleaved orthogonal designs (CIODs), but with a lower peak-to-average ratio (PAR).

ZnO based nanowires grown by chemical vapour deposition for selective hydrogenation of acetylene alcohols

Vertically aligned ZnO nanowires (NWs) with a length of 1.5-10 mu m and a mean diameter of ca. 150 nm were grown by chemical vapour deposition onto a c-oriented ZnO seed layer which was deposited by atomic layer deposition on Si substrates. The substrates were then spin-coated with an ethanol solution containing Pd nanoparticles with an average size of 2.7 and 4.5 nm. A homogeneous distribution of the Pd nanoparticles on ZnO NWs has been obtained using both Pd particle series. The catalytic activity of the ZnO NWs and Pd/ZnO NWs catalysts was measured in the semihydrogenation of 2-methyl-3-butyn-2-ol at 303-343 K and a pressure of 2-10 bar. The effect of the solvent used on the catalytic performance of the Pd/ZnO NWs catalyst was studied. The Pd/ZnO catalysts showed alkene selectivity of up to 95% at an alkyne conversion of 99%. A kinetic model is proposed to explain the activity and selectivity of the ZnO support and Pd/ZnO catalysts.