139 research outputs found
Complex Networks of Social Support: Exploring the Roles of Parents, Families, and Mentors in the Lives of Young Adult Gay and Bisexual Men.
Various structural, interactional, and functional characteristics of young adult (18-29 year-old) gay and bisexual menâs (YGBM) social support networks remain unexamined in the public health literature. Without clearer understanding of the parent, family, and mentor roles in the lives of YGBM, the linkages between social support and health status also remain unclear. These linkages may be critical to understand given the health disparities impacting YGBM. In the first study, I explored the roles of perceived maternal and paternal social support in YGBMâs substance use behaviors. I examined the associations between parental supports and substance use and tested a stress-buffering hypothesis examining if supports moderated the associations between sexuality-based victimization and substance use. Results indicated that neither maternal nor paternal supports moderated these associations. However, in main effects models, maternal and paternal supports were associated with abstinence from cigarette smoking and marijuana use, respectively. In the second study, I explored how YGBM defined their families, and examined whether perceived familial social support and familial social undermining were associated with psychological distress among YGBM within and across different family types. Results indicated that support and undermining were negatively and positively associated, respectively, with depression and anxiety. These associations varied with respect to the type of family that YGBM defined, suggesting that family network content plays a role in shaping perceptions of support and undermining. In the third study, based on qualitative interviews with providers, I explored the role of mentors in the lives of young Black and Latino men who have sex with men (YBLMSM). Results indicated several issues, including homophobia and lack of visibility, influencing development of mentoring relationships by creating opportunities and barriers for social connections. Mentors also served multiples purposes in the lives of YBLMSM, acting as role models and contributing to the psychological well-being and the social and economic advancement of YBLMSM. My findings underscore the need to consider the role of mothers and fathers, families of origin and chosen families, and mentors in the health and well-being of YBLMSM. Overall, I also demonstrate that YBLMSM are embedded in rich but also complex networks of social support.PhDHealth Behavior and Health EducationUniversity of Michigan, Horace H. Rackham School of Graduate Studieshttp://deepblue.lib.umich.edu/bitstream/2027.42/133327/1/jhsoler_1.pd
Time-frequency Grassmannian signalling for MIMO multi-channel-frequency-flat systems
In this paper, we consider the application of non-coherent Grassmannian signalling in practical multi-channel-frequency-flat multiple-input multiple-output (MIMO) wireless communication systems. In these systems, Grassmannian signalling, originally developed for single-channel block-fading systems, is not readily applicable. In particular, in such systems, the channel coefficients are constant across time and frequency, which implies that spectrally-efficient signalling ought to be jointly structured over these domains. To approach this goal, we develop a concatenation technique that yields a spectrally-efficient time-frequency Grassmannian signalling scheme, which enables the channel coherence bandwidth to be regarded as an additional coherence time. This scheme is shown to achieve the high signal-to-noise ratio non-coherent capacity of MIMO channels when the fading coefficients are constant over a time-frequency block. This scheme is also applicable in fast fading systems with coherence bandwidth exceeding that of one subchannel. The proposed scheme is independent of the symbol duration, i.e., the channel use duration, and is thus compatible with the transmit filter designs in current systems.The work of the first and second authors is supported, in part, by the Natural Sciences and Engineering Research Council of Canada (NSERC). This work is also supported, in part, by Huawei Canada Co., Ltd., in part, by the Ontario Ministry of Economic Development and Innovation's ORF-RE (Ontario Research Fund-Research Excellence) program, and, in part, by the Ministerio de Ciencia e Innovacion (project number TEC2011-27723-C02-02). The associate editor coordinating the review of this paper and approving it for publication was Z. Wang.Fouad, YMM.; Gohary, RH.; Cabrejas Peñuelas, J.; Yanikomeroglu, H.; Calabuig Soler, D.; Roger Varea, S.; Monserrat Del RĂo, JF. (2015). Time-frequency Grassmannian signalling for MIMO multi-channel-frequency-flat systems. IEEE Communications Letters. 19(3):475-478. https://doi.org/10.1109/LCOMM.2014.2386873S47547819
One-neutron transfer, complete fusion, and incomplete fusion from the Be 9 + Au 197 reaction
In this work, one-neutron transfer (pickup and stripping), complete and incomplete fusion cross sections for the Be9+Au197 system were measured over a wide range of energies around the Coulomb barrier by the offline Îł-ray detection method. Coupled-channel calculations were used to determine the elastic, inelastic, and transfer cross sections. Coupled reaction channel calculations were performed to derive the one-neutron stripping and pickup cross sections. Three-body continuum discretized coupled-channel calculations were used to determine the effect of the breakup channel on the other reaction mechanisms. The reduced complete and total fusion were found to be hindered above and enhanced below the Coulomb barrier compared with the universal fusion function due to the breakup plus transfer effects.Fil: Gollan Scilipotti, Fernando Daniel. ComisiĂłn Nacional de EnergĂa AtĂłmica. Gerencia del Ărea de InvestigaciĂłn y Aplicaciones No Nucleares. Gerencia FĂsica (Centro AtĂłmico Constituyentes). Proyecto Tandar; Argentina. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas; ArgentinaFil: Abriola, Daniel Hugo. ComisiĂłn Nacional de EnergĂa AtĂłmica. Gerencia del Ărea de InvestigaciĂłn y Aplicaciones No Nucleares. Gerencia FĂsica (Centro AtĂłmico Constituyentes). Proyecto Tandar; ArgentinaFil: Arazi, Andres. ComisiĂłn Nacional de EnergĂa AtĂłmica. Gerencia del Ărea de InvestigaciĂłn y Aplicaciones No Nucleares. Gerencia FĂsica (Centro AtĂłmico Constituyentes). Proyecto Tandar; Argentina. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas; ArgentinaFil: Cardona, Maria Angelica. ComisiĂłn Nacional de EnergĂa AtĂłmica. Gerencia del Ărea de InvestigaciĂłn y Aplicaciones No Nucleares. Gerencia FĂsica (Centro AtĂłmico Constituyentes). Proyecto Tandar; Argentina. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas; ArgentinaFil: de BarbarĂĄ, Ezequiel. ComisiĂłn Nacional de EnergĂa AtĂłmica. Gerencia del Ărea de InvestigaciĂłn y Aplicaciones No Nucleares. Gerencia FĂsica (Centro AtĂłmico Constituyentes). Proyecto Tandar; ArgentinaFil: de JesĂșs, JoaquĂn. ComisiĂłn Nacional de EnergĂa AtĂłmica. Gerencia del Ărea de InvestigaciĂłn y Aplicaciones No Nucleares. Gerencia FĂsica (Centro AtĂłmico Constituyentes). Proyecto Tandar; Argentina. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas; ArgentinaFil: Hojman, Daniel Leonardo. ComisiĂłn Nacional de EnergĂa AtĂłmica. Gerencia del Ărea de InvestigaciĂłn y Aplicaciones No Nucleares. Gerencia FĂsica (Centro AtĂłmico Constituyentes). Proyecto Tandar; Argentina. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas; ArgentinaFil: Id Betan, Rodolfo Mohamed. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas. Centro CientĂfico TecnolĂłgico Conicet - Rosario. Instituto de FĂsica de Rosario. Universidad Nacional de Rosario. Instituto de FĂsica de Rosario; ArgentinaFil: Lubian, J.. Universidade Federal Fluminense; BrasilFil: Pacheco, Alberto Jorge. ComisiĂłn Nacional de EnergĂa AtĂłmica. Gerencia del Ărea de InvestigaciĂłn y Aplicaciones No Nucleares. Gerencia FĂsica (Centro AtĂłmico Constituyentes). Proyecto Tandar; Argentina. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas; ArgentinaFil: Paes, BĂĄrbara. ComisiĂłn Nacional de EnergĂa AtĂłmica. Gerencia del Ărea de InvestigaciĂłn y Aplicaciones No Nucleares. Gerencia FĂsica (Centro AtĂłmico Constituyentes). Proyecto Tandar; ArgentinaFil: Schneider, David Marcelo. ComisiĂłn Nacional de EnergĂa AtĂłmica. Gerencia del Ărea de InvestigaciĂłn y Aplicaciones No Nucleares. Gerencia FĂsica (Centro AtĂłmico Constituyentes). Proyecto Tandar; Argentina. Consejo Nacional de Investigaciones CientĂficas y TĂ©cnicas; ArgentinaFil: Soler, H. O.. Universidade Federal Fluminense; Brasi
Non-coherent MIMO Communication for the 5th Generation Mobile: Overview and Practical Aspects
[EN] Current cellular technologies are based on the concept of coherent communication, in which the channel matrix used for demodulation is estimated via reference or pilot signals. Coherent systems involve a significant increase of the signaling overhead, either when the number of Transmission Points (TP) is increased, due to the use of Coordinated Multipoint transmission/reception (CoMP)
with Multiple-Input Multiple-Output (MIMO) processing, or when mobile channel changes rapidly. Another disadvantage of coherent communications is the performance degradation caused by channel estimation errors. Both drawbacks of coherent communication motivate the use of non-coherent techniques. Although there are many theoretical studies on the performance of non-coherent schemes in MIMO systems, their impact on real-world cellular systems is still unknown. This paper focuses on
bringing non-coherent techniques into practical systems using CoMP and/or MIMO processing.This work was performed in the framework of the FP7project ICT-317669 METIS, which is partly funded by the European Union.Roger Varea, S.; Cabrejas Peñuelas, J.; Calabuig Soler, D.; Monserrat Del RĂo, JF.; Fouad, Y.; Gohary, RH.; Yanikomeroglu, H. (2014). Non-coherent MIMO Communication for the 5th Generation Mobile: Overview and Practical Aspects. Waves. 6:5-15. http://hdl.handle.net/10251/52904S515
Non-Coherent Open-Loop MIMO Communications Over Temporally-Correlated Channels
[EN] This paper investigates the use of non-coherent communication techniques for open-loop transmission over temporally-correlated Rayleigh-fading MIMO channels. These techniques perform data detection without knowing the instantaneous channel coefficients. Three non-coherent Multiple Input Multiple Output (MIMO) schemes, namely, differential unitary space-time modulation, differential space-time block code, and Grassmannian signaling, are compared with several state-of-the-art training-based coherent schemes. This paper shows that the non-coherent schemes are meaningful alternatives to training-based communication, specially as the number of transmit antennas increases. In particular, for more than two transmit antennas, non-coherent communication provides a clear advantage in medium to high mobility scenarios.This work was supported in part by the Ministerio de Economia y Competitividad, Spain, under Grant TEC2014-60258-C2-1-R, in part by the European Regional Development Fund, in part by the European Union through the H2020 Project METIS-II under Grant 671680, in part by Huawei Canada Company, Ltd., and in part by the Ontario Ministry of Economic Development and Innovation's through the Ontario Research Fund-Research Excellence Program.Cabrejas Peñuelas, J.; Roger Varea, S.; Calabuig Soler, D.; Fouad, YMM.; Gohary, RH.; Monserrat Del RĂo, JF.; Yanikomeroglu, H. (2016). Non-Coherent Open-Loop MIMO Communications Over Temporally-Correlated Channels. IEEE Access. 4:6161-6170. https://doi.org/10.1109/ACCESS.2016.2580680S61616170
LGBT community, social network characteristics, and smoking behaviors in young sexual minority women.
Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/106605/1/LGBT community, social network characteristics, and smoking behaviors in young sexual minority women.pd
In Support of a Patient-Driven Initiative and Petition to Lower the High Price of Cancer Drugs
Comment in
Lowering the High Cost of Cancer Drugs--III. [Mayo Clin Proc. 2016]
Lowering the High Cost of Cancer Drugs--I. [Mayo Clin Proc. 2016]
Lowering the High Cost of Cancer Drugs--IV. [Mayo Clin Proc. 2016]
In Reply--Lowering the High Cost of Cancer Drugs. [Mayo Clin Proc. 2016]
US oncologists call for government regulation to curb drug price rises. [BMJ. 2015
Global human footprint on the linkage between biodiversity and ecosystem functioning in reef fishes
Copyright: © 2011 Mora et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.Difficulties in scaling up theoretical and experimental results have raised controversy over the consequences of biodiversity loss for the functioning of natural ecosystems. Using a global survey of reef fish assemblages, we show that in contrast to previous theoretical and experimental studies, ecosystem functioning (as measured by standing biomass) scales in a non-saturating manner with biodiversity (as measured by species and functional richness) in this ecosystem. Our field study also shows a significant and negative interaction between human population density and biodiversity on ecosystem functioning (i.e., for the same human density there were larger reductions in standing biomass at more diverse reefs). Human effects were found to be related to fishing, coastal development, and land use stressors, and currently affect over 75% of the world's coral reefs. Our results indicate that the consequences of biodiversity loss in coral reefs have been considerably underestimated based on existing knowledge and that reef fish assemblages, particularly the most diverse, are greatly vulnerable to the expansion and intensity of anthropogenic stressors in coastal areas
Contrasting nitrogen fertilization treatments impact xylem gene expression and secondary cell wall lignification in Eucalyptus
Association Between Preexisting Versus Newly Identified Atrial Fibrillation and Outcomes of Patients With Acute Pulmonary Embolism
Background Atrial fibrillation (AF) may exist before or occur early in the course of pulmonary embolism (PE). We determined the PE outcomes based on the presence and timing of AF. Methods and Results Using the data from a multicenter PE registry, we identified 3 groups: (1) those with preexisting AF, (2) patients with new AF within 2 days from acute PE (incident AF), and (3) patients without AF. We assessed the 90-day and 1-year risk of mortality and stroke in patients with AF, compared with those without AF (reference group). Among 16 497 patients with PE, 792 had preexisting AF. These patients had increased odds of 90-day all-cause (odds ratio [OR], 2.81; 95% CI, 2.33-3.38) and PE-related mortality (OR, 2.38; 95% CI, 1.37-4.14) and increased 1-year hazard for ischemic stroke (hazard ratio, 5.48; 95% CI, 3.10-9.69) compared with those without AF. After multivariable adjustment, preexisting AF was associated with significantly increased odds of all-cause mortality (OR, 1.91; 95% CI, 1.57-2.32) but not PE-related mortality (OR, 1.50; 95% CI, 0.85-2.66). Among 16 497 patients with PE, 445 developed new incident AF within 2 days of acute PE. Incident AF was associated with increased odds of 90-day all-cause (OR, 2.28; 95% CI, 1.75-2.97) and PE-related (OR, 3.64; 95% CI, 2.01-6.59) mortality but not stroke. Findings were similar in multivariable analyses. Conclusions In patients with acute symptomatic PE, both preexisting AF and incident AF predict adverse clinical outcomes. The type of adverse outcomes may differ depending on the timing of AF onset.info:eu-repo/semantics/publishedVersio
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