Nested Codes for Constrained Memory and for Dirty Paper

Dirty paper coding are relevant for wireless networks, multiuser channels, and digital watermarking. We show that the problem of dirty paper is essentially equivalent to some classes of constrained memories, and we explore the binary so-called nested codes, which are used for efficient coding and error-correction on such channels and memories. © Springer-Verlag Berlin Heidelberg 2006

Braess's Paradox in Wireless Networks: The Danger of Improved Technology

When comparing new wireless technologies, it is common to consider the effect that they have on the capacity of the network (defined as the maximum number of simultaneously satisfiable links). For example, it has been shown that giving receivers the ability to do interference cancellation, or allowing transmitters to use power control, never decreases the capacity and can in certain cases increase it by $\Omega(\log (\Delta \cdot P_{\max}))$, where $\Delta$ is the ratio of the longest link length to the smallest transmitter-receiver distance and $P_{\max}$ is the maximum transmission power. But there is no reason to expect the optimal capacity to be realized in practice, particularly since maximizing the capacity is known to be NP-hard. In reality, we would expect links to behave as self-interested agents, and thus when introducing a new technology it makes more sense to compare the values reached at game-theoretic equilibria than the optimum values. In this paper we initiate this line of work by comparing various notions of equilibria (particularly Nash equilibria and no-regret behavior) when using a supposedly "better" technology. We show a version of Braess's Paradox for all of them: in certain networks, upgrading technology can actually make the equilibria \emph{worse}, despite an increase in the capacity. We construct instances where this decrease is a constant factor for power control, interference cancellation, and improvements in the SINR threshold ($\beta$), and is $\Omega(\log \Delta)$ when power control is combined with interference cancellation. However, we show that these examples are basically tight: the decrease is at most O(1) for power control, interference cancellation, and improved $\beta$, and is at most $O(\log \Delta)$ when power control is combined with interference cancellation

Genotyping Of Kell, Duffy, Kidd And Rhd In Patients With β Thalassemia

Determination of Rh, Kell, Duffy and Kidd phenotypes in addition to ABO is used to prevent the alloimmunization to red blood cells (RBCs) antigens and as part of the antibody identification process in patients with β Thalassemia. However, phenotyping in these patients can be time consuming and difficult to interpret. In these situations, it would be valuable to have an alternative to hemagglutination tests to determine the patient's antigen profile. We used PCR-RFLP to genotype such patients. DNA was prepared from 50 patients with β Thalassemia who had been phenotyped by routine hemagglutination, and tested for Kell, Kidd, Duffy/ GATA mutation by PCR-RFLP. RHD/non-D was analysed by PCR product size associated to RHD gene sequence in intron 4 and exon 10/3'UTR. The genotyping assays were performed without knowledge of phenotype results. For RHD/non-D, 47 were RhD+ and RHD+/RHCE+, and 3 were RhD- and RHD-/RHCE+. For Kell, 48 kk were K2K2 and 2 Kk were K1K2. For Duffy, of 44 samples that had normal GATA box, 8 Fy(a+b-) were FYA/FYA, 15 Fy(a+b+) were FYB/FYB, and 19 Fy(a+b+) were FYA/FYB; of the other 4 samples 3 were FYA/FYB and heterozygous GATA mutation, and 1 Fy(a-b-) was FYB/FYB, homozygous GATA mutation. Two samples phenotyped as Fy(a+b-) that had normal GATA, presented the 265T/298 A mutations and two samples phenotyped as Fy(a-b+) were genotyped was FYA/FYB. For Kidd, 15 Jk(a+b) were JKA/JKA, 12 Jk(a-b+) were JKB/JKB, and 20 Jk(a+b+) were JKA/JKB. Three samples phenotyped as JK(a+b+) were genotyped as JKB/JKB. Genotype is more accurate than phenotype for determination of blood groups in polytransfused patients with β Thalassemia. Genotyping in these patients can be helpful to select antigen-negative RBCs for transfusion.2226976Blumberg, N., Peck, K., Ross, K., Avila, E., Immune response to chronic red blood cell transfusion (1983) Vox Sang, 44, pp. 212-217Economidou, J., Constantoulakis, M., Augoustaki, O., Adinolfi, M., Frequency of antibodies to various antigenic determinants in polytransfused patients with homozygous thalassemia in Greece (1971) Vox Sang, 20, p. 252Sirchia, G., Zanella, A., Parravicini, A., Morelati, F., Rebulla, P., Masera, G., Red cell alloantibodies in patients with thalassemia major. Results of na Italian cooperative study (1985) Transfusion, 25, p. 110Spanos, T., Karageorga, M., Ladis, V., Peristeri, J., Hatziliami, A., Kattamis, C., Red cell alloantibodies in patients with thalassemia (1990) Vox Sang, 58, p. 50Greenwalt, T.J., Zelenski, K.R., Transfusion support for hemoglobinopathies (1984) Clin. Haematol., 13, pp. 151-165Charache, S., Problems in transfusion therapy (1990) N. Engl. J. Med., 322, pp. 1666-1668. , editorialPerkins, H.A., The safety of the blood supply: Making decisions in transfusion medicine (1992) Blood Safety: Current Challenges, pp. 125-150. , Nance SJ, ed. Bethesda: American Association of Blood BanksColes, S.M., Klein, H.G., Holland, P.V., Alloimmunization in two multitransfused patient populations (1981) Transfusion, 21, pp. 462-466Michail-Merianou, V., Pamphili-Panouspoulou, L., Piperi-Lowes, L., Pelegrinis, E., Karaklis, A., Alloimmunization to red cell antigens in thalassemia: Comparative study of usual versus better-match transfusion programmes (1987) Vox Sang, 52, p. 95Reid, M.E., Yazdanbakhsh, K., Molecular insights into blood groups and implications for blood transfusions (1998) Current Opinion in Hematology, 5, pp. 93-102Avent, N.D., Human erythrocyte antigen expression: Its molecular bases (1997) Br. J. Biom. Sci., 54, pp. 16-37Lee, T.H., Donegan, E., Slichter, S., Bush, M.P., Transient increase in circulating donor leucocytes after allogeneic transfusions in Immunocompetent recipients compatible with donor cell proliferation (1995) Blood, 85, pp. 1207-1214Adams, F.T., Davenport, R.D., Rcardon, D.A., Roth, M.S., Detection of circulating donor white blood cells in patients receiving multiple trasnfusions (1992) Blood, 80, pp. 551-555Lee, T.-H., Paglieroni, T., Ohro, H., Holland, P.V., Bush, M.P., Longterm multi-lineage chimerism of donor leucocytes in transfused trauma patients (1996) Blood, 88, p. 265. , abstrRios, M., Cash, K., Strupp, A., Uehlinger, J., Reid, M.E., DNA from urine sediment or buccal cells can be used for blood group molecular genotyping (1999) Immunehematology, 15, pp. 61-65Reid, M.E., Rios, M., Powell, D., Charles-Pierre, D., Malavade, V., DNA from blood samples can be used to genotype patients who have recently received a transfusion (2000) Transfusion, 40, pp. 1-6Davies, L., Dibner, M.D., Battey, J.F., (1986) Basic Methods in Molecular Biology, , Elsevier Science Publishing Co. Inc., New YorkLee, S., Wu, X., Reid, M.E., Zelinski, T., Redman, C., Molecular basis of the Kell (K1) phenotype (1995) Blood, 85, pp. 912-916Olivès, B., Merriman, M., Bailly, P., Bain, S., Barnett, A., Todd, J., Cartron, J.-P., Merriman, T., The molecular basis of the Kidd blood group polymorphism and its lack of association with type 1 diabetes susceptibility (1997) Hum. Mol. Genet., 6, pp. 1017-1020Chaudhuri, A., Polyakova, J., Zbrezezna, V., Williams, K., Gulati, S., Pogo, A.O., Cloning of glycoprotein D cDNA, which encodes the major subunit of the Duffy blood group system and the receptor for the Plasmodium vivax malaria parasite (1993) Proc. Natl. Acad. Sci. USA, 90, pp. 10793-10797Iwamoto, S., Omi, T., Kajii, E., Ikemoto, S., Genomic organization of the glycophorin D gene: Duffy blood group Fy a/Fy b alloantigen system is associated with a polymorphism at the 44-amino residue (1995) Blood, 85, pp. 622-626Tournamille, C., Collin, Y., Cartron, J.-P., Van Le Kim, C., Disruption of a GATA motif in the Duffy gene promotor abolishes erythroid gene expression in Duffy-negative individuals (1995) Nature Genet., 10, pp. 224-228Rios, M., Reid, M.E., Naime, D., Chaudhuri, A., Pogo, A.O., Bianco, C., Importance of GATA box analysis in genotyping for the Duffy blood group system (1997) Transfusion, 37 (S), pp. 101S. , abstrZimmerman, P.A., Woolley, I., Masinde, G.L., Miller, S.M., McNamara, D.T., Hazlett, F., Mgone Alpers, M.P., Kazura, J.W., Emergence of FY*A(null) in a Plasmodium vivax-endemic region of Papua New Guinea (1999) Proc Natl Acad Sci. USA, 96 (24), pp. 13973-13977. , Nov 23Olsson, M.L., Hansson, C., Akesson, I.E., Avent, N.D., Daniels, G.L., Detection of the common alleles at the Duffy blood group locus by allele-specific primer PCR (1997) Transfusion, 37 (S), pp. 102S. , abstrCartron, J.-P., Bailly, P., Van Le Kim, C., Insights into the structure and function of membrane polypeptides carrying blood group antigens (1998) Vox Sang, 74 (SUPPL. 2), pp. 29-64Huang, C.H., Molecular insights into the Rh protein family and associated antigens (1997) Curr Opin Hematol., 4, pp. 94-103Huang, C.H., Blumenfeld, O.O., MNSs blood groups and major glycophorins: Molecular basis for allelic variation (1995) Molecular Basis of Major Human Blood Group Antigens, pp. 153-183. , cartron J-P, Pouger P, eds. New York: Plenum PressAvent, N.D., Reid, M.E., The Rh Blood group system: A review (2000) Blood, 95, pp. 1-1

Multiuser Cognitive Radio Networks: An Information Theoretic Perspective

Achievable rate regions and outer bounds are derived for three-user interference channels where the transmitters cooperate in a unidirectional manner via a noncausal message-sharing mechanism. The three-user channel facilitates different ways of message-sharing between the primary and secondary (or cognitive) transmitters. Three natural extensions of unidirectional message-sharing from two users to three users are introduced: (i) Cumulative message sharing; (ii) primary-only message sharing; and (iii) cognitive-only message sharing. To emphasize the notion of interference management, channels are classified based on different rate-splitting strategies at the transmitters. Standard techniques, superposition coding and Gel'fand-Pinsker's binning principle, are employed to derive an achievable rate region for each of the cognitive interference channels. Simulation results for the Gaussian channel case are presented; they enable visual comparison of the achievable rate regions for different message-sharing schemes along with the outer bounds. These results also provide useful insights into the effect of rate-splitting at the transmitters, which aids in better interference management at the receivers.Comment: 50 pages, 15 figures, submitted to IEEE Transactions on Information Theor

Meta-analysis of Genome-Wide Association Studies for Extraversion: Findings from the Genetics of Personality Consortium

Extraversion is a relatively stable and heritable personality trait associated with numerous psychosocial, lifestyle and health outcomes. Despite its substantial heritability, no genetic variants have been detected in previous genome-wide association (GWA) studies, which may be due to relatively small sample sizes of those studies. Here, we report on a large meta-analysis of GWA studies for extraversion in 63,030 subjects in 29 cohorts. Extraversion item data from multiple personality inventories were harmonized across inventories and cohorts. No genome-wide significant associations were found at the single nucleotide polymorphism (SNP) level but there was one significant hit at the gene level for a long non-coding RNA site (LOC101928162). Genome-wide complex trait analysis in two large cohorts showed that the additive variance explained by common SNPs was not significantly different from zero, but polygenic risk scores, weighted using linkage information, significantly predicted extraversion scores in an independent cohort. These results show that extraversion is a highly polygenic personality trait, with an architecture possibly different from other complex human traits, including other personality traits. Future studies are required to further determine which genetic variants, by what modes of gene action, constitute the heritable nature of extraversion