88 research outputs found
Utilization-Aware Adaptive Back-Pressure Traffic Signal Control
Back-pressure control of traffic signal, which computes
the control phase to apply based on the real-time queue
lengths, has been proposed recently. Features of it include (i)
provably maximum stability, (ii) low computational complexity,
(iii) no requirement of prior knowledge in traffic demand, and
(iv) requirement of only local information at each intersection.
The latter three points enable it to be completely distributed
over intersections. However, one major issue preventing backpressure
control from being used in practice is the utilization
of the intersection, especially if the control phase period is
fixed, as is considered in existing works. In this paper, we
propose a utilization-aware adaptive algorithm of back-pressure
traffic signal control, which makes the duration of the control
phase adaptively dependent on the real-time queue lengths
and strives for high utilization of the intersection. While
advantages embedded in the back-pressure control are kept,
we prove that this algorithm is work-conserving and achieves
the maximum utilization. Simulation results on an isolated
intersection show that the proposed adaptive algorithm has
better control performance than the fixed-period back-pressure
control presented in previous works
Objective Analysis of Marker Bias in Higher Education
Marker bias has been a serious factor contributing to discrepancy in assessments. In this study we analyze one year students' results in a Business Faculty within an Australian university to understand the extent of variation induced by marker bias in multiple marker scenarios. The study shows interesting insights regarding the marking trends of a particular marker, and shows variations among markers in a particular course. The study paves the way for quantification of marker variation through objective analysis
Priprava, in vitro i in vivo evaluacija bioadhezivnih mikrosfera s algino-pektinom: ispitivanje utjecaja polimera pomoÄu multiple poredbene analize
Ionotropic gelation was used to entrap aceclofenac into algino-pectinate bioadhesive microspheres as a potential drug carrier for the oral delivery of this anti-inflammatory drug. Microspheres were investigated in vitro for possible sustained drug release and their use in vivo as a gastroprotective system for aceclofenac. Polymer concentration and polymer/drug ratio were analyzed for their influence on microsphere properties. The microspheres exhibited good bioadhesive property and showed high drug entrapment efficiency. Drug release profiles exhibited faster release of aceclofenac from alginate microspheres whereas algino-pectinate microspheres showed prolonged release. Dunett\u27s multiple comparison analyis suggested a significant difference in percent inhibition of paw edema when the optimized formulation was compared to pure drug. It was concluded that the algino-pectinate bioadhesive formulations exhibit promising properties of a sustained release form for aceclofenac and that they provide distinct tissue protection in the stomach.U radu je opisana priprava algino-pektinskih bioadhezivnih mikrosfera protuupalnog lijeka aceklofenaka metodom ionotropnog geliranja. In vitro je ispitivana moguÄnost postupnog oslobaÄanja ljekovite tvari iz mikrosfera te moguÄnost upotrebe mikrosfera kao gastroprotektivnog sustava za isporuku aceklofenaka in vivo. Ispitivan je utjecaj koncentracije polimera i omjera polimera i lijeka na svojstva mikrosfera. Mikrosfere su bile bioahezivne i sadrĆŸavale su veliki udio lijeka. OslobaÄanje aceklofenaka iz alginatnih mikrosfera bilo je brĆŸe, a iz mikrosfera s algino-pektinom usporeno. Dunnetova multipla analiza ukazuje na znaÄajnu razliku u postotku inhibicije edema ĆĄape kada se usporede optimizirana formulacija i Äista ljekovita tvar. MoĆŸe se zakljuÄiti da su bioadhezivne mikrosfere s algino-pektinom povoljne za usporeno oslobaÄanje aceklofenaka te da pruĆŸaju umjerenu zaĆĄtitu sluznice ĆŸeluca
Hydrogel composite containing azelaic acid and tea tree essential oil as a therapeutic strategy for Propionibacterium and testosterone-induced acne.
Azelaic acid (AzA) is a USFDA bioactive prescribed against acne vulgaris. It possesses delivery challenges like poor aqueous solubility, low skin-penetrability, and dose-dependent side effects, which could be overcome by its synergistic combination with tea tree oil (TTO) as a microemulsion (ME)-based hydrogel composite. AzA-TTO ME was prepared to employ pseudo-ternary phase diagram construction. The best AzA-TTO ME was of uniform size (polydispersity indexââ90%), and negative zeta potential (-1.42â±â0.25% mV) values. ME hydrogel composite with optimum rheological and textural attributes showed better permeation, retention, and skin-compliant characteristics, vis-a-vis marketed formulation (Azidermâą) when evaluated in Wistar rat skin. In vitro antibacterial efficacy in bacterial strains, i.e., Staphylococcus aureus, Propionibacterium acne, and Staphylococcus epidermidis, was evaluated employing agar well plate diffusion and broth dilution assay. ME hydrogel has shown an increase in zone of inhibition by two folds and a decrease in minimum inhibitory concentration (MIC) by eightfold against P. acnes vis-a-vis AzA. Finally, ME hydrogel composite exhibited a better reduction in the papule density (93.75â±â1.64%) in comparison to Azidermâą 72.69â±â4.67%) on acne as developed in rats by inducing testosterone. Thus, the developed AzA-TTO ME hydrogel composite promises an efficacious and comparatively safer drug delivery system for the topical therapy of acne vulgaris
UÄinak topljivosti na kinetiku oslobaÄanja vodotopljivih i vodonetopljivih lijekova iz matriksnog sustava na bazi HPMC
The purpose of the present research work was to observe the effects of drug solubility on the release kinetics of water soluble verapamil hydrochloride and insoluble aceclofenac from polymer based matrix formulations. Matrix formulations were prepared by the direct compression method. The formulations were evaluated for various physical parameters. Along with the dynamics of water uptake and erosion, SEM and in vitro drug release of tablets were studied. Applying an exponential equation, it was found that the kinetics of soluble drug release followed anomalous non-Fickian diffusion transport whereas insoluble drug showed zero-order release. SEM study showed pore formation on the tablet surface that differed depending on drug solubility. t-Test pointed to a significant difference in the amount of both drugs released due to their difference in solubility. Solubility of the drug affects the kinetics and the mechanism of drug release.Cilj rada bio je praÄenje uÄinka topljivosti na kinetiku oslobaÄanja vodotopljivog verapamil hidroklorida i netopljivog lijeka aceklofenaka iz matriksnih sustava na bazi hidrofilnog polimera. Matriksni sustavi pripravljeni su izravnom metodom kompresije. Uz ispitivanje uobiÄajenih fizikalnih svojstava, ispitivana je i dinamika primanja vode, te erozija, SEM i in vitro oslobaÄanje ljekovite tvari iz tableta. Primjenom eksponencijalne jednadĆŸbe utvrÄeno je da mehanizam oslobaÄanja topljivih lijekova slijedi anomalni ne-Fickov difuzijski transport, dok netopljivi lijekovi slijede kinetiku nultog reda. SEM ispitivanja pokazala su pore na povrĆĄini matriksa ovisne o topljivosti ljekovite tvari. T-test ukazuje da koliÄina osloboÄenog lijeka znaÄajno ovisi o njegovoj topljivosti. Topljivost lijeka ima znaÄajan uÄinak na kinetiku i mehanizam oslobaÄanja
Prevalence of drug-resistant pulmonary tuberculosis in India: systematic review and meta-analysis
Effects of antibiotic resistance, drug target attainment, bacterial pathogenicity and virulence, and antibiotic access and affordability on outcomes in neonatal sepsis: an international microbiology and drug evaluation prospective substudy (BARNARDS)
Background
Sepsis is a major contributor to neonatal mortality, particularly in low-income and middle-income countries (LMICs). WHO advocates ampicillinâgentamicin as first-line therapy for the management of neonatal sepsis. In the BARNARDS observational cohort study of neonatal sepsis and antimicrobial resistance in LMICs, common sepsis pathogens were characterised via whole genome sequencing (WGS) and antimicrobial resistance profiles. In this substudy of BARNARDS, we aimed to assess the use and efficacy of empirical antibiotic therapies commonly used in LMICs for neonatal sepsis.
Methods
In BARNARDS, consenting motherâneonates aged 0â60 days dyads were enrolled on delivery or neonatal presentation with suspected sepsis at 12 BARNARDS clinical sites in Bangladesh, Ethiopia, India, Pakistan, Nigeria, Rwanda, and South Africa. Stillborn babies were excluded from the study. Blood samples were collected from neonates presenting with clinical signs of sepsis, and WGS and minimum inhibitory concentrations for antibiotic treatment were determined for bacterial isolates from culture-confirmed sepsis. Neonatal outcome data were collected following enrolment until 60 days of life. Antibiotic usage and neonatal outcome data were assessed. Survival analyses were adjusted to take into account potential clinical confounding variables related to the birth and pathogen. Additionally, resistance profiles, pharmacokineticâpharmacodynamic probability of target attainment, and frequency of resistance (ie, resistance defined by in-vitro growth of isolates when challenged by antibiotics) were assessed. Questionnaires on health structures and antibiotic costs evaluated accessibility and affordability.
Findings
Between Nov 12, 2015, and Feb 1, 2018, 36â285 neonates were enrolled into the main BARNARDS study, of whom 9874 had clinically diagnosed sepsis and 5749 had available antibiotic data. The four most commonly prescribed antibiotic combinations given to 4451 neonates (77·42%) of 5749 were ampicillinâgentamicin, ceftazidimeâamikacin, piperacillinâtazobactamâamikacin, and amoxicillin clavulanateâamikacin. This dataset assessed 476 prescriptions for 442 neonates treated with one of these antibiotic combinations with WGS data (all BARNARDS countries were represented in this subset except India). Multiple pathogens were isolated, totalling 457 isolates. Reported mortality was lower for neonates treated with ceftazidimeâamikacin than for neonates treated with ampicillinâgentamicin (hazard ratio [adjusted for clinical variables considered potential confounders to outcomes] 0·32, 95% CI 0·14â0·72; p=0·0060). Of 390 Gram-negative isolates, 379 (97·2%) were resistant to ampicillin and 274 (70·3%) were resistant to gentamicin. Susceptibility of Gram-negative isolates to at least one antibiotic in a treatment combination was noted in 111 (28·5%) to ampicillinâgentamicin; 286 (73·3%) to amoxicillin clavulanateâamikacin; 301 (77·2%) to ceftazidimeâamikacin; and 312 (80·0%) to piperacillinâtazobactamâamikacin. A probability of target attainment of 80% or more was noted in 26 neonates (33·7% [SD 0·59]) of 78 with ampicillinâgentamicin; 15 (68·0% [3·84]) of 27 with amoxicillin clavulanateâamikacin; 93 (92·7% [0·24]) of 109 with ceftazidimeâamikacin; and 70 (85·3% [0·47]) of 76 with piperacillinâtazobactamâamikacin. However, antibiotic and country effects could not be distinguished. Frequency of resistance was recorded most frequently with fosfomycin (in 78 isolates [68·4%] of 114), followed by colistin (55 isolates [57·3%] of 96), and gentamicin (62 isolates [53·0%] of 117). Sites in six of the seven countries (excluding South Africa) stated that the cost of antibiotics would influence treatment of neonatal sepsis
Observation of gravitational waves from the coalescence of a 2.5â4.5 Mâ compact object and a neutron star
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