Improved IEEE 802.11 point coordination function considering fiber-delay difference in distributed antenna systems

In this paper, we present an improved IEEE 802.11 wireless local-area network (WLAN) medium access control (MAC) mechanism for simulcast radio-over-fiber-based distributed antenna systems where multiple remote antenna units (RAUs) are connected to one access point (AP). In the improved mechanism, the fiber delay between RAUs and central unit is taken into account in a modification to the conventional point coordination function (PCF) that achieves coordination by a centralized algorithm. Simulation results show that the improved PCF outperforms the distributed coordination function (DCF) in both the basic-access and request/clear-to-send modes in terms of the total throughput and the fairness among RAU

Red Blood Cell Transfusion Strategy for Upper Gastrointestinal Bleeding

Acute upper gastrointestinal bleeding (UGIB) is a potentially lethal and frequent digestive disease. It is mainly divided into the nonvariceal UGIB and variceal bleeding according to the source of bleeding. Red blood cell transfusion is the core therapeutic option for the management of acute UGIB. In this chapter, we reviewed the primary evidence from meta‐analyses and large‐scale randomized controlled trials regarding red blood cell transfusion strategy for acute UGIB

DIMP53-1:A novel small-molecule dual inhibitor of p53-MDM2/X interactions with multifunctional p53-dependent anticancer properties

The transcription factor p53 plays a crucial role in cancer development and dissemination, and thus, p53-targeted therapies are among the most encouraging anticancer strategies. In human cancers with wild-type (wt) p53, its inactivation by interaction with murine double minute (MDM)2 and MDMX is a common event. Simultaneous inhibition of the p53 interaction with both MDMs is crucial to restore the tumor suppressor activity of p53. Here, we describe the synthesis of the new tryptophanol-derived oxazoloisoindolinone DIMP53-1 and identify its activity as a dual inhibitor of the p53-MDM2/X interactions using a yeast-based assay. DIMP53-1 caused growth inhibition, mediated by p53 stabilization and upregulation of p53 transcriptional targets involved in cell cycle arrest and apoptosis, in wt p53-expressing tumor cells, including MDM2- or MDMX-overexpressing cells. Importantly, DIMP53-1 inhibits the p53-MDM2/X interactions by potentially binding to p53, in human colon adenocarcinoma HCT116 cells. DIMP53-1 also inhibited the migration and invasion of HCT116 cells, and the migration and tube formation of HMVEC-D endothelial cells. Notably, in human tumor xenograft mice models, DIMP53-1 showed a p53-dependent antitumor activity through induction of apoptosis and inhibition of proliferation and angiogenesis. Finally, no genotoxicity or undesirable toxic effects were observed with DIMP53-1. In conclusion, DIMP53-1 is a novel p53 activator, which potentially binds to p53 inhibiting its interaction with MDM2 and MDMX. Although target-directed, DIMP53-1 has a multifunctional activity, targeting major hallmarks of cancer through its antiproliferative, proapoptotic, antiangiogenic, anti-invasive, and antimigratory properties. DIMP53-1 is a promising anticancer drug candidate and an encouraging starting point to develop improved derivatives for clinical application

Origin and Dynamical Evolution of Neptune Trojans - I: Formation and Planetary Migration

We present the results of detailed dynamical simulations of the effect of the migration of the four giant planets on both the transport of pre-formed Neptune Trojans, and the capture of new Trojans from a trans-Neptunian disk. We find that scenarios involving the slow migration of Neptune over a large distance (50Myr to migrate from 18.1AU to its current location) provide the best match to the properties of the known Trojans. Scenarios with faster migration (5Myr), and those in which Neptune migrates from 23.1AU to its current location, fail to adequately reproduce the current day Trojan population. Scenarios which avoid disruptive perturbation events between Uranus and Neptune fail to yield any significant excitation of pre-formed Trojans (transported with efficiencies between 30 and 98% whilst maintaining the dynamically cold nature of these objects). Conversely, scenarios with periods of strong Uranus-Neptune perturbation lead to the almost complete loss of such pre-formed objects. In these cases, a small fraction (~0.15%) of these escaped objects are later recaptured as Trojans prior to the end of migration, with a wide range of eccentricities (<0.35) and inclinations (<40 deg). In all scenarios (including those with such disruptive interaction between Uranus and Neptune) the capture of objects from the trans-Neptunian disk (through which Neptune migrates) is achieved with efficiencies between ~0.1 and ~1%. The captured Trojans display a wide range of inclinations (<40 deg for slow migration, and <20 deg for rapid migration) and eccentricities (<0.35), and we conclude that, given the vast amount of material which undoubtedly formed beyond the orbit of Neptune, such captured objects may be sufficient to explain the entire Neptune Trojan population. (Shortened version)Comment: 25 pages, 6 figure

Atomically controlled, self-limiting procedures for growth of aluminum oxide on SiC-on-Si

Abstract number 0451, Abstract book page P-02-008Electronic devices fabricated from SiC/Si epitaxial wafers will need surface passivation and insulating coatings. For solar cell applications – and in MOS systems – Al-oxide thin film coatings have some strong advocates, not the least due to the advances of the ALD process. We have grown SiC/Si, formed by a remote CH4 plasma interacting with Si surfaces in UHV. After growing the SiC/Si system (SiC thickness between 0.5 and 5 nm; polycrystalline) a self-limiting Si-oxide layer was grown on the surface, with a thickness of around 1 nm, at 7000C. On top of this layer we deposited approximately 1 nm of Al with a Knudsen atomic source (all steps in UHV) and then reacted it thermally (at 6000C) with the Si-oxide. We monitored all the process steps and the resulting structures of the layers and the interface using synchrotron radiation induced core level photoemission at ASTRID, Aarhus, Denmark. We found similar qualities with this procedure, as for Si, i.e. an atomically sharp interface between Al-oxide and SiC, and this reaction scheme offers self-limiting behavior both of the oxidation to create Si-oxide, and to the conversion into Al-oxide, which only needs a sufficient amount of Al to affect the total conversion of the Si-oxide, while excess Al will leave the system at sufficiently elevated temperatures.publishersversionpublishe

Progress in manufacture and properties of construction materials incorporating water treatment sludge: A review

© 2019 Elsevier B.V. Water treatment sludge (WTS) management is a growing global problem for water treatment plants (WTPs) and governments. Considering the scarcity of raw materials in many parts of the planet and unique properties of WTS, extensive research has been conducted on the application of WTS in the production of construction materials such as roof tiles, bricks, lightweight aggregates, cement, concrete and geopolymers. This paper critically reviews the progress in the application of WTS in construction materials, by synthesizing results from recent studies. Research findings have revealed that incorporation of ≤10% alum-based sludge in ceramic bricks is satisfactory with a small reduction of mechanical performance. Using the iron-based sludge, the bricks presented better mechanical strength than the reference clay-bricks. Concerning WTS application in concrete, 5% replacement of cement or sand by WTS was considered as the ideal value for the application in a variety of structural and non-structural concrete without adverse effect on concrete mechanical performance. Furthermore, this paper discusses sludge-amended concrete in terms of durability, potential leaching of toxic elements and cost, and suggests topics for future research on the sustainable management of WTS

The Impact of Digital Health Interventions for the Management of Type 2 Diabetes on Health and Social Care Utilisation and Costs: A Systematic Review

BACKGROUND: Digital health interventions such as smartphone applications (mHealth) or Internet resources (eHealth) are increasingly used to improve the management of chronic conditions, such as type 2 diabetes mellitus. These digital health interventions can augment or replace traditional health services and may be paid for using healthcare budgets. While the impact of digital health interventions for the management of type 2 diabetes on health outcomes has been reviewed extensively, less attention has been paid to their economic impact. OBJECTIVE: This study aims to critically review existing literature on the impact of digital health interventions for the management of type 2 diabetes on health and social care utilisation and costs. METHODS: Studies that assessed the impact on health and social care utilisation of digital health interventions for type 2 diabetes were included in the study. We restricted the digital health interventions to information provision, self-management and behaviour management. Four databases were searched (MEDLINE, EMBASE, PsycINFO and EconLit) for articles published between January 2010 and March 2021. The studies were analysed using a narrative synthesis approach. The risk of bias and reporting quality were appraised using the ROBINS-I checklist. RESULTS: The review included 22 studies. Overall, studies reported mixed evidence on the impact of digital health interventions on health and social care utilisation and costs, and suggested this impact differs according to the healthcare utilisation component. For example, digital health intervention use was associated with lower medication use and fewer outpatient appointments, whereas evidence on general practitioner visits and inpatient admissions was mixed. Most reviewed studies focus on a single component of healthcare utilisation. CONCLUSIONS: The review shows no clear evidence of an impact of digital health interventions on health and social care utilisation or costs. Further work is needed to assess the impact of digital health interventions across a broader range of care utilisation components and settings, including social and mental healthcare services. CLINICAL TRIAL REGISTRATION: The study protocol was registered on PROSPERO before searches began in April 2021 (registration number: CRD42020172621)