220 research outputs found
Nitrogen doping in the carbon matrix for Li-ion hybrid supercapacitors: state of the art, challenges and future prospective
Li-ion hybrid supercapacitors (LiHSCs) have emerged as an extremely attractive energy storage system by combining the prime advantages of Li-ion batteries and supercapacitors. As a common electrode material in both lithium ion batteries and supercapacitors, graphene and activated carbons offer a tunable porous structure with high chemical, thermal and physical stability, which in turn results in excellent electronic conductivity and improved capacity as compared with the other electrodes. Elemental nitrogen doping in graphene and activated carbons is believed to further improve their performance. In this review, the state of the art of hybrid supercapacitors is briefly summarized with an emphasis on the use of graphene and activated carbons. Subsequent doping of graphene and activated carbons with nitrogen in LiHSCs is also emphasized
Software Fault Localization Using N -gram Analysis
Abstract. A major portion of software development effort is spent in testing and debugging. Execution sequence collected in the testing phase can be a rich source of information for locating the fault in the program, but the exact execution sequence of a program, i.e., the actual order of execution of the statements in the program, is seldom used due to the huge volume. In this study, we apply data mining techniques on this data to reduce the debugging time by narrowing down the possible location of the fault. Our method applies N -gram analysis to rank the executable statements of a software by level of suspicion. We conducted three case studies to demonstrate the effectiveness of our proposed method. We also present comparison with other approaches, and illustrate the potential of our method
Comparison of the reverse bevel versus Franseen type endoscopic ultrasound needle
BACKGROUNDReverse bevel (RB) needle is widely used for endoscopic ultrasound fine needle biopsy (EUS-FNB). A 3-plane symmetrical needle with Franseen geometry (FG) has recently become available. AIMTo compare the clinical efficacy of FG to that of RB needle.METHODSA retrospective cohort study of all adult patients who underwent EUS-FNB for solid and mixed lesions either with 22G RB needle or 22G FG needle between January 2016 and February 2019 was undertaken. All cytology slides were reviewed by an independent gastrointestinal cytopathologist blinded to the needle used and the initial cytology report. The primary and secondary outcomes were to assess the sample adequacy using Euro-cytology criteria and the number of cell clusters, respectively.RESULTSTwo hundred and twenty six procedures were included in the study. RB needle was used in 128 procedures and FG needle in 98 procedures. The baseline characteristics of both groups were comparable. On multivariable analysis, FG needle (P = 0.02) and location of the lesion (P < 0.01) were independently associated with adequate tissue. Further, the use of FG needle (P = 0.04) and the size of the lesion (P = 0.02) were independently associated with acquisition of increased number of cell clusters.CONCLUSIONFG needle is superior to RB needle in acquiring adequate tissue and attaining higher number of cell clusters for solid and mixed lesions
Aligning Retrograde Nuclear Cluster Orbits with an Active Galactic Nucleus Accretion Disc
Stars and stellar remnants orbiting a supermassive black hole (SMBH) can
interact with an active galactic nucleus (AGN) disc. Over time, prograde
orbiters (inclination ) decrease inclination, as well as
semi-major axis () and eccentricity () until orbital alignment with the
gas disc ("disc capture"). Captured stellar-origin black holes (sBH) add to the
embedded AGN population which drives sBH-sBH mergers detectable in
gravitational waves using LIGO-Virgo-KAGRA (LVK) or sBH-SMBH mergers detectable
with LISA (Laser Interferometer Space Antenna). Captured stars can be tidally
disrupted by sBH or the SMBH or rapidly grow into massive 'immortal' stars.
Here, we investigate the behaviour of polar and retrograde orbiters () interacting with the disc. We show that retrograde stars are
captured faster than prograde stars, flip to prograde () during
capture and decrease dramatically towards the SMBH. For sBH, we find a
critical angle , below which retrograde sBH decay
towards embedded prograde orbits (), while for sBH decay towards embedded retrograde orbits (). sBH near polar orbits () and stars on nearly
embedded retrograde orbits () show the greatest decreases
in . Whether a star is captured by the disc within an AGN lifetime depends
primarily on disc density, and secondarily on stellar type and initial . For
sBH, disc capture time is longest for polar orbits, low mass sBH and lower
density discs. Larger mass sBH should typically spend more time in AGN discs,
with implications for the embedded sBH spin distribution.Comment: 10 pages, 7 figures, 1 table; submitted to MNRA
Post-partum follow-up of women with gestational diabetes mellitus: Effectiveness, determinants, and barriers
Background: Despite the recommendations for postpartum blood glucose monitoring post gestational diabetes mellitus (GDM); scientific evidence reveals that these recommendations may not be fully complied to. This study aimed to follow-up women up to 2 years post-delivery with pregnancies complicated by GDM and healthy controls to assess this fact.Methods: Women with GDM (n = 78) and normal glucose tolerant (n = 89) delivered in 2014 were followed up for 2 years. They were informed and enquired via telephone about their blood glucose screening, physical activity, postpartum complications, and current weight status of mother and baby.Results: Women with previous GDM were older and reported higher body weight 2 years post-delivery. At the 2 year follow-up, n = 11 (14.1%) participants had developed diabetes, all with previous GDM. Both weight at birth (3.8 ± 0.5 kg) and at 2-year (10.7 ± 2.3 kg) for the babies born to GDM mothers was significantly higher than the NGT group babies (2.6 ± 0.63 and 7.1 ± 1.4 kg; p \u3c .05). Only 27 women regularly opted for T2DM screening via monitoring blood glucose or HbA1c levels postpartum. The top reason for failed screening included: believing that GDM would disappear after delivery, and being occupied with the baby.Conclusions: The high incidence of T2DM in women with previous GDM is an alarming finding. Given this trend, systematic follow-up programs are needed to reduce obesity and diabetes risk
They were Saying that I was a ‘typical Chinese mum’: Chinese Parents’ Experiences of Parent-Teacher Partnerships for Their Autistic Children
Effective parent-teacher partnerships improve outcomes for autistic students. Yet, we know little about what effective partnerships look like for parents of autistic children from different backgrounds. We conducted interviews with 17 Chinese parents of autistic children attending Australian kindergartens/schools to understand their experiences. Parents appreciated the acceptance, opportunities and supports they received in Australia. They had high expectations of children; expectations not often shared by educators. Parents were respectful of teachers’ expertise and polite and undemanding in interactions. Nevertheless, parents were frustrated by inconsistent teaching quality and inadequate communication. Navigating systems was also challenging and parents faced discrimination from teachers and their community. Recommendations include fostering open home-school communication, proactively seeking parents’ expertise about children and explicitly scaffolding parents’ self-advocacy
Conceivable security risks and authentication techniques for smart devices
With the rapidly escalating use of smart devices and fraudulent transaction of users’ data from their devices, efficient and reliable techniques for authentication of the smart devices have become an obligatory issue. This paper reviews the security risks for mobile devices and studies several authentication techniques available for smart devices. The results from field studies enable a comparative evaluation of user-preferred authentication mechanisms and their opinions about reliability, biometric authentication and visual authentication techniques
Characterisation of feline renal cortical fibroblast cultures and their transcriptional response to transforming growth factor beta 1
Chronic kidney disease (CKD) is common in geriatric cats, and the most prevalent pathology is chronic tubulointerstitial inflammation and fibrosis. The cell type predominantly responsible for the production of extra-cellular matrix in renal fibrosis is the myofibroblast, and fibroblast to myofibroblast differentiation is probably a crucial event. The cytokine TGF-β1 is reportedly the most important regulator of myofibroblastic differentiation in other species. The aim of this study was to isolate and characterise renal fibroblasts from cadaverous kidney tissue of cats with and without CKD, and to investigate the transcriptional response to TGF-β1
Influenza in Outpatient ILI Case-Patients in National Hospital-Based Surveillance, Bangladesh, 2007–2008
Recent population-based estimates in a Dhaka low-income community suggest that influenza was prevalent among children. To explore the epidemiology and seasonality of influenza throughout the country and among all age groups, we established nationally representative hospital-based surveillance necessary to guide influenza prevention and control efforts.We conducted influenza-like illness and severe acute respiratory illness sentinel surveillance in 12 hospitals across Bangladesh during May 2007–December 2008. We collected specimens from 3,699 patients, 385 (10%) which were influenza positive by real time RT-PCR. Among the sample-positive patients, 192 (51%) were type A and 188 (49%) were type B. Hemagglutinin subtyping of type A viruses detected 137 (71%) A/H1 and 55 (29%) A/H3, but no A/H5 or other novel influenza strains. The frequency of influenza cases was highest among children aged under 5 years (44%), while the proportions of laboratory confirmed cases was highest among participants aged 11–15 (18%). We applied kriging, a geo-statistical technique, to explore the spatial and temporal spread of influenza and found that, during 2008, influenza was first identified in large port cities and then gradually spread to other parts of the country. We identified a distinct influenza peak during the rainy season (May–September).Our surveillance data confirms that influenza is prevalent throughout Bangladesh, affecting a wide range of ages and causing considerable morbidity and hospital care. A unimodal influenza seasonality may allow Bangladesh to time annual influenza prevention messages and vaccination campaigns to reduce the national influenza burden. To scale-up such national interventions, we need to quantify the national rates of influenza and the economic burden associated with this disease through further studies
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