WhiteHaul: white space spectrum aggregation system for backhaul

Today almost half the world's population does not have Internet access. This is particularly the case in rural and undeserved regions where providing Internet access infrastructure is challenging and expensive. To this end, we present demonstration of WhiteHaul [5], a low-cost hybrid cross-layer aggregation system for TV White Space (TVWS) based backhaul. WhiteHaul features a custom-designed frequency conversion substrate that efficiently handles multiple noncontiguous chunks of TVWS spectrum using multiple low-cost COTS 802.11n/ac cards but with a single antenna. At the software layer, WhiteHaul uses MPTCP as a link-level tunnel abstraction to efficiently aggregate multiple chunks of the TVWS spectrum via a novel uncoupled, cross-layer congestion control algorithm. This demo illustrates the unique features of the WhiteHaul system based on a prototype implementation employing a modified version of MPTCP Linux Kernel and a custom-designed conversion substrate. Using this prototype, we highlight the performance of the WhiteHaul system under various configurations and network conditions

WhiteHaul: an efficient spectrum aggregation system for low-cost and high capacity backhaul over white spaces

We address the challenge of backhaul connectivity for rural and developing regions, which is essential for universal fixed/mobile Internet access. To this end, we propose to exploit the TV white space (TVWS) spectrum for its attractive properties: low cost, abundance in under-served regions and favorable propagation characteristics. Specifically, we propose a system called WhiteHaul for the efficient aggregation of the TVWS spectrum tailored for the backhaul use case. At the core of WhiteHaul are two key innovations: (i) a TVWS conversion substrate that can efficiently handle multiple non-contiguous chunks of TVWS spectrum using multiple low cost 802.11n/ac cards but with a single antenna; (ii) novel use of MPTCP as a link-level tunnel abstraction and its use for efficiently aggregating multiple chunks of the TVWS spectrum via a novel uncoupled, cross-layer congestion control algorithm. Through extensive evaluations using a prototype implementation of WhiteHaul, we show that: (a) WhiteHaul can aggregate almost the whole of TV band with 3 interfaces and achieve nearly 600Mbps TCP throughput; (b) the WhiteHaul MPTCP congestion control algorithm provides an order of magnitude improvement over state of the art algorithms for typical TVWS backhaul links. We also present additional measurement and simulation based results to evaluate other aspects of the WhiteHaul design

Expression of bacterial virulence factors and cytokines during in vitro macrophage infection by enteroinvasive Escherichia coli and Shigella flexneri: a comparative study

Enteroinvasive Escherichia coli (EIEC) and Shigellaspp cause bacillary dysentery in humans by invading and multiplying within epithelial cells of the colonic mucosa. Although EIEC and Shigellashare many genetic and biochemical similarities, the illness caused by Shigellais more severe. Thus, genomic and structure-function molecular studies on the biological interactions of these invasive enterobacteria with eukaryotic cells have focused on Shigella rather than EIEC. Here we comparatively studied the interactions of EIEC and of Shigella flexneriwith cultured J774 macrophage-like cells. We evaluated several phenotypes: (i) bacterial escape from macrophages after phagocytosis, (ii) macrophage death induced by EIEC and S. flexneri, (iii) macrophage cytokine expression in response to infection and (iv) expression of plasmidial (pINV) virulence genes. The results showed thatS. flexneri caused macrophage killing earlier and more intensely than EIEC. Both pathogens induced significant macrophage production of TNF, IL-1 and IL-10 after 7 h of infection. Transcription levels of the gene invasion plasmid antigen-C were lower in EIEC than in S. flexneri throughout the course of the infection; this could explain the diminished virulence of EIEC compared to S. flexneri.FAPES

Does direction of results of abstracts submitted to scientific conferences on drug addiction predict full publication?

<p>Abstract</p> <p>Background</p> <p>Data from scientific literature show that about 63% of abstracts presented at biomedical conferences will be published in full. Some studies have indicated that full publication is associated with the direction of results (publication bias). No study has looked into the occurrence of publication bias in the field of addiction.</p> <p>Objectives</p> <p>To investigate whether the significance or direction of results of abstracts presented at the major international scientific conference on addiction is associated with full publication</p> <p>Methods</p> <p>The conference proceedings of the US Annual Meeting of the College on Problems of Drug Dependence (CPDD), were handsearched for abstracts of randomized controlled trials and controlled clinical trials that evaluated interventions for prevention, rehabilitation and treatment of drug addiction in humans (years searched 1993–2002). Data regarding the study designs and outcomes reported were extracted. Subsequent publication in peer reviewed journals was searched in MEDLINE and EMBASE databases, as of March 2006.</p> <p>Results</p> <p>Out of 5919 abstracts presented, 581 met the inclusion criteria; 359 (62%) conference abstracts had been published in a broad variety of peer reviewed journals (average time of publication 2.6 years, SD +/- 1.78). The proportion of published studies was almost the same for randomized controlled trials (62.4%) and controlled clinical trials (59.5%) while studies that reported positive results were significantly more likely to be published (74.5%) than those that did not report statistical results (60.9%.), negative or null results (47.1%) and no results (38.6%), Abstracts reporting positive results had a significantly higher probability of being published in full, while abstracts reporting null or negative results were half as likely to be published compared with positive ones (HR = 0.48; 95%CI 0.30–0.74)</p> <p>Conclusion</p> <p>Clinical trials were the minority of abstracts presented at the CPDD; we found evidence of possible publication bias in the field of addiction, with negative or null results having half the likelihood of being published than positive ones.</p

Suppression of HBV by Tenofovir in HBV/HIV coinfected patients : a systematic review and meta-analysis

Background: Hepatitis B coinfection is common in HIV-positive individuals and as antiretroviral therapy has made death due to AIDS less common, hepatitis has become increasingly important. Several drugs are available to treat hepatitis B. The most potent and the one with the lowest risk of resistance appears to be tenofovir (TDF). However there are several questions that remain unanswered regarding the use of TDF, including the proportion of patients that achieves suppression of HBV viral load and over what time, whether suppression is durable and whether prior treatment with other HBV-active drugs such as lamivudine, compromises the efficacy of TDF due to possible selection of resistant HBV strains. Methods: A systematic review and meta-analysis following PRISMA guidelines and using multilevel mixed effects logistic regression, stratified by prior and/or concomitant use of lamivudine and/or emtricitabine. Results: Data was available from 23 studies including 550 HBV/HIV coinfected patients treated with TDF. Follow up was for up to seven years but to ensure sufficient power the data analyses were limited to three years. The overall proportion achieving suppression of HBV replication was 57.4%, 79.0% and 85.6% at one, two and three years, respectively. No effect of prior or concomitant 3TC/FTC was shown. Virological rebound on TDF treatment was rare. Interpretation: TDF suppresses HBV to undetectable levels in the majority of HBV/HIV coinfected patients with the proportion fully suppressed continuing to increase during continuous treatment. Prior treatment with 3TC/FTC does not compromise efficacy of TDF treatment. The use of combination treatment with 3TC/FTC offers no significant benefit over TDF alone

Proteomic Analysis of Polypeptides Captured from Blood during Extracorporeal Albumin Dialysis in Patients with Cholestasis and Resistant Pruritus

Albumin dialysis using the molecular adsorbent recirculating system (MARS) is a new therapeutic approach for liver diseases. To gain insight into the mechanisms involved in albumin dialysis, we analyzed the peptides and proteins absorbed into the MARS strong anion exchange (SAX) cartridges as a result of the treatment of patients with cholestasis and resistant pruritus. Proteins extracted from the SAX MARS cartridges after patient treatment were digested with two enzymes. The resulting peptides were analyzed by multidimensional liquid chromatography coupled to tandem mass spectrometry. We identified over 1,500 peptide sequences corresponding to 144 proteins. In addition to the proteins that are present in control albumin-derived samples, this collection includes 60 proteins that were specific to samples obtained after patient treatment. Five of these proteins (neutrophil defensin 1 [HNP-1], secreted Ly-6/uPAR-related protein 1 [SLURP1], serum amyloid A, fibrinogen alpha chain and pancreatic prohormone) were confirmed to be removed by the dialysis procedure using targeted selected-reaction monitoring MS/MS. Furthermore, capture of HNP-1 and SLURP1 was also validated by Western blot. Interestingly, further analyses of SLURP1 in serum indicated that this protein was 3-fold higher in cholestatic patients than in controls. Proteins captured by MARS share certain structural and biological characteristics, and some of them have important biological functions. Therefore, their removal could be related either to therapeutic or possible adverse effects associated with albumin dialysis

Effects of Different Up-Dosing Regimens for Hymenoptera Venom Immunotherapy on Serum CTLA-4 and IL-10

BACKGROUND: Cytotoxic T lymphocyte associated antigen-4 (CTLA-4) is involved in the activation pathways of T lymphocytes. It has been shown that the circulating form of CTLA-4 is elevated in patients with hymenoptera allergy and can be down regulated by immunotherapy. OBJECTIVE: to assess the effects on CTLA-4 of venom immunotherapy, given with different induction protocols: conventional (6 weeks), rush (3 days) or ultra rush (1 day). METHODS: Sera from patients with hymenoptera allergy were collected at baseline and at the end of the induction phase. CTLA-4 and IL-10 were assayed in the same samples. A subset of patients were assayed also after 12 months of VIT maintenance. RESULTS: Ninety-four patients were studied. Of them, 50 underwent the conventional induction, 20 the rush and 24 the ultra-rush. Soluble CTLA-4 was detectable in all patients at baseline, and significantly decreased at the end of the induction, irrespective of its duration. Of note, a significant decrease of sCTLA-4 could be seen already at 24 hours. In parallel, IL-10 significantly increased at the end of the induction. At 12 months, sCTLA-4 remained low, whereas IL-10 returned to the baseline values. CONCLUSIONS: Serum CTLA4 is an early marker of the immunological effects of venom immunotherapy, and its changes persist after one year of maintenance treatment

Lpd depletion reveals that SRF specifies radial versus tangential migration of pyramidal neurons

During corticogenesis, pyramidal neurons (~80% of cortical neurons) arise from the ventricular zone, pass through a multipolar stage to become bipolar and attach to radial glia[superscript 1, 2], and then migrate to their proper position within the cortex[superscript 1, 3]. As pyramidal neurons migrate radially, they remain attached to their glial substrate as they pass through the subventricular and intermediate zones, regions rich in tangentially migrating interneurons and axon fibre tracts. We examined the role of lamellipodin (Lpd), a homologue of a key regulator of neuronal migration and polarization in Caenorhabditis elegans, in corticogenesis. Lpd depletion caused bipolar pyramidal neurons to adopt a tangential, rather than radial-glial, migration mode without affecting cell fate. Mechanistically, Lpd depletion reduced the activity of SRF, a transcription factor regulated by changes in the ratio of polymerized to unpolymerized actin. Therefore, Lpd depletion exposes a role for SRF in directing pyramidal neurons to select a radial migration pathway along glia rather than a tangential migration mode.Ruth L. Kirschstein National Research Service Award (grant F32- GM074507)National Institutes of Health (U.S.) (grant # GM068678

Ethnic differences in dissatisfaction with sexual life in patients with type 2 diabetes in a Swedish town

<p>Abstract</p> <p>Background</p> <p>The first aim of this study was to analyze whether self-reported satisfaction with one's sexual life was associated with ethnicity (Swedish and Assyrian/Syrian) in patients with type 2 diabetes. The second was to study whether the association between satisfaction with one's sexual life and ethnicity remained after controlling for possible confounders such as marital status, HbA1c, medication, and presence of other diseases.</p> <p>Methods</p> <p>This cross-sectional, questionnaire-based study was conducted at four primary health care centers in the Swedish town of Södertälje. A total of 354 persons (173 ethnic Assyrians/Syrians and 181 ethnic Swedes) participated.</p> <p>Results</p> <p>The total prevalence of self-reported dissatisfaction with one's sexual life in both groups was 49%. No significant ethnic differences were found in the outcome. In the final model, regardless of ethnicity, the odds ratio (OR) for self-reported dissatisfaction with one's sexual life in those ≥ 70 years old was 2.52 (95% CI 1.33-4.80). Among those living alone or with children, the OR was more than three times higher than for married or cohabiting individuals (OR = 3.10, 95% CI 1.60-6.00). Those with other diseases had an OR 1.89 times (95% CI 1.10-3.40) higher than those without other diseases.</p> <p>Conclusions</p> <p>The findings demonstrate that almost half of participants were dissatisfied with their sexual life and highlight the importance of sexual life to people with type 2 diabetes. This factor should not be ignored in clinical evaluations. Moreover, the findings demonstrate that it is possible to include questions on sexual life in investigations of patients with type 2 diabetes and even in other health-related, questionnaire studies, despite the sensitivity of the issue of sexuality.</p