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Abstract-When mobiles cannot support multiple antennas due to size or other constraints, conventional space-time coding cannot be used to provide uplink transmit diversity. To address this limitation, the concept of cooperation diversity has been introduced, where mobiles achieve uplink transmit diversity by relaying each other's messages. A particularly powerful variation of this principle is coded cooperation. Instead of a simple repetition relay, coded cooperation partitions the codewords of each mobile and transmits portions of each codeword through independent fading channels. This paper presents two extensions to the coded cooperation framework. First, we increase the diversity of coded cooperation in the fast-fading scenario via ideas borrowed from space-time codes. We calculate bounds for the bit-and block-error rates to demonstrate the resulting gains. Second, since cooperative coding contains two code components, it is natural to apply turbo codes to this framework. We investigate the application of turbo codes in coded cooperation and demonstrate the resulting gains via error bounds and simulations.

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Since the prevailing form of hormone replacement therapy is associated with the development of cancer in breast and endometrial tissues, alternatives are needed for the management of menopausal symptoms. Formulations of Trifolium pratense L. (red clover) are being used to alleviate menopauseassociated hot flashes but have shown mixed results in clinical trials. The strobiles of Humulus lupulus L. (hops) have been reported to contain the prenylflavanone, 8-prenylnaringenin (8-PN) as the most estrogenic constituent, and this was confirmed using an estrogen receptor ligand screening assay utilizing ultrafiltration mass spectrometry. Extracts of hops and red clover and their individual constituents including 8-PN, 6-prenylnaringenin (6-PN), isoxanthohumol (IX), and xanthohumol (XN) from hops, and daidzein, formononetin, biochanin A, and genistein from red clover, were compared using a variety of in vitro estrogenic assays. The IC 50 values for the estrogen receptor α and β binding assays were 15 and 27 μg/mL, respectively, for hops and 18.0 and 2.0 μg/mL, respectively, for the red clover extract. Both of the extracts, genistein, and 8-PN activated the estrogen response element (ERE) in Ishikawa cells while the extracts, biochanin A, genistein, and 8-PN significantly induced ERE-luciferase expression in MCF-7 cells. Hop and red clover extracts, as well as 8-PN upregulated progesterone receptor (PR) mRNA in the Ishikawa cell line. In the MCF-7 cell line, PR mRNA was significantly upregulated by the extracts, biochanin A, genistein, 8-PN, and IX. The two extracts had EC 50 values of 1.1 and 1.9 μg/mL, respectively, in the alkaline phosphatase induction assay. Based on these data, hops and red clover could be attractive for development as herbal dietary supplements to alleviate menopause-associated symptoms.

This paper proposes several Concordance Correlation Coefficient (CCC) indices to measure the agreement among k raters, with each rater having multiple (m) readings from each of the n subjects for continuous and categorical data. In addition, for normal data, this paper also proposes the coverage probability (CP) and total deviation index (TDI). Those indices are used to measure intra, inter and total agreement among all raters. Intra-rater indices are used to measure the agreement among the multiple readings from the same rater. Inter-rater indices are used to measure the agreement among different raters based on the average of multiple readings. Total-rater indices are used to measure the agreement among different raters based on individual readings. In addition to the agreement, the paper also assess intra, inter, and total precision and accuracy. Through a two-way mixed model, all CCC, precision and accuracy, TDI, and CP indices are expressed as functions of variance components, and GEE method is used to obtain the estimates and perform inferences for all the functions of variance components. Each of previous proposed approaches for assessing agreement becomes one of the special case of the proposed approach. For continuous data, when m approaches infinity, the proposed estimates reduce to the agreement indices proposed by Barnhart et al. (2005). When m = 1, the proposed estimate reduces to the ICC proposed by Carrasco and Jover (2003). When m = 1, the proposed estimate also reduces to the OCCC proposed by Lin (1989), King and Chinchilli (2001a) and Barnhart et al. (2002). When m = 1 and k = 2, the proposed estimate reduces to the original CCC proposed by Lin (1989). For categorical data, when k = 2 and m = 1, the proposed estimate and its associated inference reduce to the kappa for binary data and weighted kappa with squared weight for ordinal data.

Abstract-This correspondence studies linear receivers for MIMO channels under frequency-nonselective (flat) quasi-static Rayleigh fading. The outage probability and diversity gain of MMSE and Zero Forcing (ZF) receivers are investigated. It is found that contrary to intuition, MMSE and zero-forcing receivers may not perform similarly at high SNR. Assuming M transmit and N receive antennas, the zero-forcing receiver always has diversity N −M +1, unlike the MMSE receiver, whose behavior can vary. Under separate spatial encoding, where data from each transmit antenna is separately encoded, MMSE is no better than ZF in terms of diversity. But for joint spatial encoding systems, where an encoded stream is sent from all the antennas, the MMSE receiver achieves diversity M N at low spectral efficiencies but has diversity only M − N + 1 at high spectral efficiencies.