Search results for "Node"

The Changing Pattern of Human Immunodeficiency Virus Type 1 Infection in Intravenous Drug Users

1992

A cross-sectional seroepidemiologic study was carried out between 1985 and 1990 in 1,567 heterosexual intravenous drug users who had been seen at the AIDS Regional Reference Center in Palermo, Italy, to evaluate the rate of human immunodeficiency virus type 1 (HIV-1) seroprevalence in this group and its long-term trend. Sixty serum samples collected from drug users in 1980 and 1983, before the founding of the Center (1985), were tested as well. Some demographic and behavioral risk factors were studied in a subgroup of intravenous drug users enrolled in 1985, 1987, and 1990 for their possible association with HIV-1. These factors were also studied in relation to hepatitis B virus infection, …

Effectiveness of a screening program for HBV, HCV, and HIV infections in African migrants to Sicily

2021

BACKGROUND Migrants from Africa are vulnerable to viral infections during their journey. METHODS Migrants who arrived in western Sicily were offered early screening for hepatitis B virus (HBV), hepatitis C virus (HCV), and human immunodeficiency virus (HIV) infection. A questionnaire was administered to evaluate risk factors, and antiviral therapy was offered to subjects with active infection. A multiple regression analysis and adjusted odds ratio were obtained to evaluate risk factors. RESULTS Overall, 2,639 of 2,751 (95.9%) migrants who arrived between 2015 and 2017 accepted screening and 1,911 (72.4%) completed the questionnaire. HBsAg was positive in 257 (9.7%) migrants, 24 (0.9%) were …

A non-valvular infective endocarditis in an HIV patient with myocardiopathy

2006

A 37-year-old woman presented in the emergency department revealing a history of HIV infection and C virus hepatitis diagnosed 15 years ago, acquired after a period of intravenous drug abusing. The patient was receiving triple antiHIV therapy and was in an A1 stage (last lymphocite recount of CD4: 0.63 10/l and no AIDS disease manifestation to the present moment). She described episodes, starting 20 days before, of torathic pain coexisting with shivers. There were no symptoms or signs of any focal infection. In the physical examination the only findings were a temperature of 38.4 8C, a 4 cm hepatomegaly and lipodystrophy. We found in the electrocardiogram a sinus rhythm, 96 bpm and no ST se…

Cytotoxic capability and the associated proteomic profile of cell-free coelomic fluid extracts from the edible sea cucumber Holothuria tubulosa on He…

2022

Hepatocellular carcinoma (HCC) is an aggressive cancer histotype and one of the most common types of cancer worldwide. The identification of compounds that might intervene to restrain neoplastic cell growth appears imperative due to its elevated overall mortality. The marine environment represents a reservoir rich in bioactive compounds in terms of primary and secondary metabolites produced by aquatic animals, mainly invertebrates. In the present study, we determined whether the water-soluble cell-free extract of the coelomic fluid (CFE) of the edible sea cucumber Holothuria tubulosa could play an anti-HCC role in vitro by analyzing the viability and locomotory behavior, cell cycle distribu…

Adaptive Collision Avoidance through Implicit Acknowledgments in WSNs

2008

The large number of nodes, typical of many sensor network deployments, and the well-known hidden terminal problem make collision avoidance an essential goal for the actual employment of WSN technology. Collision avoidance is traditionally dealt with at the MAC Layer and plenty of different solutions have been proposed, which however have encountered limited diffusion because of their incompatibility with commonly available devices.In this paper we propose an approach to collision avoidance which is designed to work over a standard MAC Layer, namely the IEEE 802.15.4 MAC, and is based on application-controlled delays of packet transmission times. The proposed scheme is simple, decentralized …

Cooperative RTS/CTS MAC with relay selection in distributed wireless networks

2009

This paper proposes a cooperative multiple access protocol based on the Distributed Coordination Function (DCF) Request-To-Send/Clear-To-Send (RTS/CTS) scheme for distributed wireless networks. It answers three key questions concerning cooperation from the network perspective, namely when to cooperate, whom to cooperate with and how to protect cooperative transmissions. According to our protocol, the cooperation is initiated only if the direct transmission fails. An optimal relay node is selected in a distributed manner according to instantaneous relay channel conditions without prior information or extra signaling among relay candidates in the network. An additional three-way handshake is …

Revisit of RTS/CTS Exchange in High-Speed IEEE 802.11 Networks

2005

IEEE 802.11 medium access control (MAC), called distributed coordination function (DCF), provides two different access modes, namely, 2-way (basic access) and 4-way (RTS/CTS) handshaking. The 4-way handshaking has been introduced in order to combat the hidden terminal phenomenon. It has been also proved that such a mechanism can be beneficial even in the absence of hidden terminals, because of the collision time reduction. We analyze the effectiveness of the RTS/CTS access mode, in current 802.11b and 802.11a networks. Since the rates employed for control frame transmissions can be much lower than the rate employed for data frames, the assumption on the basis of the 4-way handshaking introd…

Anode current saturation of ALD-coated Planacon MCP-PMTs

2018

We have measured and compared the characteristics of ALD-coated Planacon MCP-PMTs (XP85112/A1-Q-L) with their non-ALD counterparts (XP85012/A1-Q). While the later show excellent performance, the ALD-coated sensors have surprisingly low current saturation levels (~two orders of magnitude lower than expected) and extremely high gain recovery time (more than 7 orders of magnitude higher than expected). We suspect that these problems might be caused by the unexpected side-effects of the ALD process. To make a definite conclusion, more samples need to be tested, preferably from different production runs. If our observation were confirmed, it would mean a serious technological setback for ALD-coa…

DIVERSIFICATION OF HIPPO SIGNALING COMPONENTS IN SELECTED METAZOAN SPECIES

La via di segnalazione intracellulare conosciuta come Hippo pathway svolge un ruolo chiave nei processi che regolano il controllo della dimensione degli organi, la proliferazione, l’apoptosi, il mantenimento delle caratteristiche di staminalità cellulare. Alterazioni nel pathway sono state descritte in molti tipi di tumori. Il nome deriva da una delle sue componenti principali, la proteina chinasi Hippo (Hpo), identificata per la prima volta in Drosophila melanogaster. Mutazioni nel gene Hpo inducevano la crescita abnorme di tessuti e organi. Componenti del pathway Hippo sono stati successivamente individuati anche nei mammiferi. Gli elementi fondamentali sono costituiti dalla proteine chin…

Diagnosing HIV infection using flow cytometry: From antigenic analyses to a specifically dedicated bead-based assay to measure viral load.

2009

SINCE the discovery of HIV in 1984 (1,2), millions have been infected and have died of AIDS. In 2006, the World Health Organization identified 40 million HIV-infected subjects, noting that antiretroviral therapy was required throughout the world (Fig. 1; http://www.who.int/hiv/data/en/index.html). Today, the situation is very similar and the HIV pandemic remains a major world health problem (3). The treatment of AIDS with highly active antiretroviral therapy (HAART) involves regular monitoring of different blood parameters, requiring the development of convenient and accurate methods that can evaluate HIV infection even in resource-poor countries (4,5). In addition to CD4 cell count, which …