A time-domain control signal detection technique for OFDM

Transmission of system-critical control information plays a key role in efficient management of limited wireless network resources and successful reception of payload data information. This paper uses an orthogonal frequency division multiplexing (OFDM) architecture to investigate the detection performance of a time-domain approach used to detect deterministic control signalling information. It considers a type of control information chosen from a finite set of information, which is known at both transmitting and receiving wireless terminals. Unlike the maximum likelihood (ML) estimation method, which is often used, the time-domain detection technique requires no channel estimation and no pilots as it uses a form of time-domain correlation as the means of detection. Results show that when compared with the ML method, the time-domain approach improves detection performance even in the presence of synchronisation error caused by carrier frequency offset

Competição interespecífica entre o parasitoide exótico Fopius arisanus e o nativo Doryctobracon areolatus (Hymenoptera Braconidae) em Anastrepha fraterculus (Diptera: Tephritidae).

SICONBIOL 2013

Recent acquisition of Helicobacter pylori by Baka Pygmies

Both anatomically modern humans and the gastric pathogen Helicobacter pylori originated in Africa, and both species have been associated for at least 100,000 years. Seven geographically distinct H. pylori populations exist, three of which are indigenous to Africa: hpAfrica1, hpAfrica2, and hpNEAfrica. The oldest and most divergent population, hpAfrica2, evolved within San hunter-gatherers, who represent one of the deepest branches of the human population tree. Anticipating the presence of ancient H. pylori lineages within all hunter-gatherer populations, we investigated the prevalence and population structure of H. pylori within Baka Pygmies in Cameroon. Gastric biopsies were obtained by esophagogastroduodenoscopy from 77 Baka from two geographically separated populations, and from 101 non-Baka individuals from neighboring agriculturalist populations, and subsequently cultured for H. pylori. Unexpectedly, Baka Pygmies showed a significantly lower H. pylori infection rate (20.8%) than non-Baka (80.2%). We generated multilocus haplotypes for each H. pylori isolate by DNA sequencing, but were not able to identify Baka-specific lineages, and most isolates in our sample were assigned to hpNEAfrica or hpAfrica1. The population hpNEAfrica, a marker for the expansion of the Nilo-Saharan language family, was divided into East African and Central West African subpopulations. Similarly, a new hpAfrica1 subpopulation, identified mainly among Cameroonians, supports eastern and western expansions of Bantu languages. An age-structured transmission model shows that the low H. pylori prevalence among Baka Pygmies is achievable within the timeframe of a few hundred years and suggests that demographic factors such as small population size and unusually low life expectancy can lead to the eradication of H. pylori from individual human populations. The Baka were thus either H. pylori-free or lost their ancient lineages during past demographic fluctuations. Using coalescent simulations and phylogenetic inference, we show that Baka almost certainly acquired their extant H. pylori through secondary contact with their agriculturalist neighbors

Adenosine A2A receptors: localization and function

Adenosine is an endogenous purine nucleoside present in all mammalian tissues, that originates from the breakdown of ATP. By binding to its four receptor subtypes (A1, A2A, A2B, and A3), adenosine regulates several important physiological functions at both the central and peripheral levels. Therefore, ligands for the different adenosine receptors are attracting increasing attention as new potential drugs to be used in the treatment of several diseases. This chapter is aimed at providing an overview of adenosine metabolism, adenosine receptors localization and their signal transduction pathways. Particular attention will be paid to the biochemistry and pharmacology of A2A receptors, since antagonists of these receptors have emerged as promising new drugs for the treatment of Parkinson's disease. The interactions of A2A receptors with other nonadenosinergic receptors, and the effects of the pharmacological manipulation of A2A receptors on different body organs will be discussed, together with the usefulness of A2A receptor antagonists for the treatment of Parkinson's disease and the potential adverse effects of these drugs

Default risk, state ownership and the cross-section of stock returns: evidence from China

We apply a structural model to estimate firm-level default risk in China and investigate the stock return predictability of default risk and the moderating effects of state ownership for the sample period from 2003 to 2015. We show unique evidence that in China, default risk is positively associated with expected stock returns and state ownership matters considerably to the return predictability of default risk. We find investors of state-owned enterprises (SOEs) are not compensated appropriately in China despite of their higher default risk exposure. Our empirical evidence supports the conjecture on shareholder advantages and suggests that a strong bargaining power of equity holders would have a negative impact on stock returns

Urban Biodiversity and Landscape Ecology: Patterns, Processes and Planning

Effective planning for biodiversity in cities and towns is increasingly important as urban areas and their human populations grow, both to achieve conservation goals and because ecological communities support services on which humans depend. Landscape ecology provides important frameworks for understanding and conserving urban biodiversity both within cities and considering whole cities in their regional context, and has played an important role in the development of a substantial and expanding body of knowledge about urban landscapes and communities. Characteristics of the whole city including size, overall amount of green space, age and regional context are important considerations for understanding and planning for biotic assemblages at the scale of entire cities, but have received relatively little research attention. Studies of biodiversity within cities are more abundant and show that longstanding principles regarding how patch size, configuration and composition influence biodiversity apply to urban areas as they do in other habitats. However, the fine spatial scales at which urban areas are fragmented and the altered temporal dynamics compared to non-urban areas indicate a need to apply hierarchical multi-scalar landscape ecology models to urban environments. Transferring results from landscape-scale urban biodiversity research into planning remains challenging, not least because of the requirements for urban green space to provide multiple functions. An increasing array of tools is available to meet this challenge and increasingly requires ecologists to work with planners to address biodiversity challenges. Biodiversity conservation and enhancement is just one strand in urban planning, but is increasingly important in a rapidly urbanising world

In Defence of Public Higher Education: Knowledge for a Successful Society (The Alternative White Paper for HE)

The present Conservative Government, like the Coalition Government that preceded it, has an ideological predisposition towards the market and its supposed benefits to consumers, but appears to have no vision of Higher Education and its benefits to students and to the whole of society. These wider societal benefits can be summarised under three aspects: * educating the next generation of the population * carrying out research to address social and scientific challenges * maintaining an independent platform for research into society and science to facilitate democratic debate. The last of these, sometimes drawn under the umbrella of ‘academic freedom’, is the basis of the historic contract between Universities and the State. We contend, following the UNESCO Recommendation (1997), that academic freedom must be sufficient to guarantee the independence of scientific inquiry, commentary and teaching. Pressures from funding agencies and the state are usually cited as the principal threats to academic independence. The last decade has seen the rise of a third threat, namely an increasing managerial interference in academic life deriving from the introduction of market imperatives. These three societal benefits are interconnected. Without independent research there can be no scientific independence and no cutting-edge teaching. Without a focus on critique and challenge, students may see ‘education’ as a mere process of accumulating ‘facts’ to meet test criteria. A narrow focus on the acquisition of qualifications undermines the education process itself. Employers have criticised graduate recruits for insufficient creativity, of being rote-taught and thus un-adaptable to a modern business subject to rapid technological change. Importantly, critical skills are necessary to meet the challenge of business and for inclusive democratic engagement. The idea of a University that unites these three aspects is undermined by a new model of Higher Education Institution that sees the investment in human capital only as a private benefit. The Government’s White Paper, Success as a Knowledge Economy, and associated legislative programme, consolidate a fee-loan (or debt-finance) model of funding which puts the costs of higher education onto new graduates and future taxpayers, while reducing taxes for current taxpayers – many of whom directly benefit from publicly-supported higher education, or from its wider public benefits. The Government suggests that it is merely replacing direct public funding with one that places the ‘student at the heart of the system’. But it proposes that public funding should be directed towards the realisation of the private benefits of higher education, and it fails to acknowledge the wider public benefits that higher education affords. In truth, the proposals place the market at the heart of the system and subordinate the student as a consumer of higher education, with loans functioning as a voucher to present at a university of choice (providing that the student has the grades required). It is our view that this new funding model is wrong in principle and deficient in practice. The regulatory framework that is being introduced in its wake will undermine the declared aims to improve teaching quality, to enhance social mobility, and to improve access and achievement. The extension of university title to for-profit providers will also threaten the wider public benefits of higher education, by allowing them to compete as single-function institutions, and giving them access to publicly-supported loans for their students without a guarantee of their longer term stability. This will intensify existing competition and encourage a ‘race to the bottom’. Our defence of an alternative vision of Higher Education takes place in the context of a dismal lack of leadership by the various mission groups representing universities in the sector – for example, Universities UK and the Russell Group – and other bodies responsible for the sector. Their willing advocacy of a fee-loan model of funding (to avoid possible cuts) has abdicated their leadership role in a proper debate on the values of public higher education. This failure to defend the values of the very public higher education they are chartered to provide is in marked contrast to representations made by another group. Lobbyists on behalf of for-profit providers are seeking a supposed ‘level-playing field’ in undergraduate degree provision, despite having no track record of success in the UK, a disastrous record in the USA, and no desire to provide any wider public benefit of their existence. The Government’s position is also in marked contrast to public attitudes. The British Social Attitudes Survey (NatCen) has, before and since the introduction of tuition fee changes, regularly asked questions about public attitudes to higher education and inequality. The majority of the population has consistently opposed high levels of student debt, believed that education has a value beyond simply providing the means to a better job, and maintained that inequality in Britain is an obstacle to the fulfillment of opportunities. Perhaps surprisingly, this commitment to the values of publicly-funded higher education is especially marked among those without graduate-level qualifications. Politicians who argue that the latter resent paying taxes to finance education for ‘middle-class people’ should seek evidence for this assertion. But the ‘debate’ among politicians, members of the BIS secretariat and corporate lobbyists over the issue has been remarkable for its superficial, un-evidenced character. It has also been remarkable for the absence of full public debate (Leach 2016). This Alternative White Paper aims to correct this imbalance. We need a proper debate about the future of UK Higher Education

In Situ-Targeting of Dendritic Cells with Donor-Derived Apoptotic Cells Restrains Indirect Allorecognition and Ameliorates Allograft Vasculopathy

Chronic allograft vasculopathy (CAV) is an atheromatous-like lesion that affects vessels of transplanted organs. It is a component of chronic rejection that conventional immuno-suppression fails to prevent, and is a major cause of graft loss. Indirect allo-recognition through T cells and allo-Abs are critical during CAV pathogenesis. We tested whether the indirect allo-response and its impact on CAV is down-regulated by in situ-delivery of donor Ags to recipient's dendritic cells (DCs) in lymphoid organs in a pro-tolerogenic fashion, through administration of donor splenocytes undergoing early apoptosis. Following systemic injection, donor apoptotic cells were internalized by splenic CD11chi CD8α+ and CD8− DCs, but not by CD11cint plasmacytoid DCs. Those DCs that phagocytosed apoptotic cells in vivo remained quiescent, resisted ex vivo-maturation, and presented allo-Ag for up to 3 days. Administration of donor apoptotic splenocytes, unlike cells alive, (i) promoted deletion, FoxP3 expression and IL-10 secretion, and decreased IFN-γ-release in indirect pathway CD4 T cells; and (ii) reduced cross-priming of anti-donor CD8 T cells in vivo. Targeting recipient's DCs with donor apoptotic cells reduced significantly CAV in a fully-mismatched aortic allograft model. The effect was donor specific, dependent on the physical characteristics of the apoptotic cells, and was associated to down-regulation of the indirect type-1 T cell allo-response and secretion of allo-Abs, when compared to recipients treated with donor cells alive or necrotic. Down-regulation of indirect allo-recognition through in situ-delivery of donor-Ag to recipient's quiescent DCs constitutes a promising strategy to prevent/ameliorate indirect allorecognition and CAV

Analysis of Inducible Nitric Oxide Synthase Gene Polymorphisms in Vitiligo in Han Chinese People

Background: Vitiligo is a chronic depigmented skin disorder with regional melanocytes depletion. The pathogenesis was not completely clarified. Recently, more and more evidence suggested that polymorphisms of some genes are associated with vitiligo risk. Here, we want to examine the association between the inducible nitric oxide synthase (iNOS) gene polymorphisms and the risk of vitiligo in Chinese populations. Methods and Principal Findings: In a hospital-based case-control study of 749 patients with vitiligo and 763 age- and sexmatched healthy controls, three polymorphisms of iNOS gene were genotyped by using the PCR-restriction fragment length polymorphism (PCR-RFLP) and mutagenically separated PCR (MS-PCR) methods, respectively. We found the iNOS-954 polymorphism was associated with a significantly higher risk of vitiligo (adjusted OR = 1.36, 95 % CI = 1.02–1.81). Furthermore, this association is more pronounced in vulgaris vitiligo, active vitiligo and vitiligo without other autoimmune diseases in the stratification study. Analysis of haplotypes showed increased risk for the C-1173C-954CEx16+14 (OR = 1.44, 95% CI = 1.01–1.74). In addition, the serum iNOS activity is significantly associated with iNOS-954 combined genotype (GC+CC) and is much higher in vitiligo patients than in the controls (P,0.01). Logistic regression analysis of iNOS activity showed increased risk between higher activity and iNOS-954 GRC variant genotype carriers (Ptrend,0.001). Conclusions and Significance: INOS gene polymorphisms may play an important role in the genetic susceptibility to th