This paper presents a new method to evaluate the reliability of a power system with high penetration of wind generation, considering the impact of not only the intermittence but also the low inertia ...characteristic of wind power. As wind generation gradually replaces conventional generation, the system stability and the reliability are negatively affected. Some of the measures employed to deal with the challenges resulting from increasing wind penetration include operating wind generators at lower levels than their available output and providing inertia so that wind generation is able to contribute to system frequency regulation. Apart from these measures, another factor that limits the amount of wind power that can be absorbed into the grid is the imposition of the frequency standard and this also affects the reliability of the system in the presence of wind penetration. The reliability evaluation approach proposed in this paper is developed using discrete convolution and implemented on an IEEE RTS-79 system with a suitable modification. Power system reliability with and without considering the impacts of wind intermittence and low inertia are compared to show the effectiveness of the proposed method.
Chronic kidney disease (CKD) affects up to 15% of the adult population and is strongly associated with other non-communicable chronic diseases including diabetes. However, there is limited ...information on a population basis of the relationship between CKD and health-related quality of life (HRQoL) and the consequent economic cost. We investigated this relationship in a representative sample in England using the 2010 Health Survey for England. Multivariable Tobit models were used to examine the relationship between HRQoL and CKD severity. HRQoL was converted to quality adjusted life year (QALY) measures by combining decrements in quality of life with reductions in life expectancy associated with increased disease severity. QALYs were adjusted for discounting and monetised using the UK threshold for reimbursement of £30,000. The QALYs were then used in conjunction with forecasted prevalence to estimate the HRQoL burden associated with CKD among individuals with diabetes up to 2025. Individuals with more severe CKD had lower HRQoL compared to those with better kidney function. Compared to those with normal/low normal kidney function and stage 1 CKD, those with stage 2, stage 3 with albuminuria and stage 4/5 CKD experienced a decrement of 0.11, 0.18 and 0.28 in their utility index, respectively. Applying the UK reimbursement threshold for a QALY, the monetised lifetime burden of reduced HRQoL due to stage 2, stage 3 with albuminuria and stage 4/5 CKD were £103,734; £83,399; £125,335 in males and £143,582; £70,288; £203,804 in females, respectively. Utilizing the predicted prevalence of CKD among individuals with diabetes mellitus, the economic burden of CKD per million of individuals with diabetes is forecasted at approximately £11.4 billion in 2025. In conclusion, CKD has a strong adverse impact on HRQoL in multiple domains. The estimated economic burden of CKD among individuals with diabetes mellitus in the UK is projected to rise markedly over time.
There is uncertainty about the effectiveness of clinical breast examination (CBE) and conflicting recommendations regarding its usefulness as a screening tool for breast cancer. This paper provides ...an overview of systematic reviews that assessed the effectiveness of CBE as a 'stand-alone' screening modality for breast cancer compared to no screening and focused on its value in low- and middle-income countries (LMICs).
We searched MEDLINE, EMBASE, Scopus, Web of Science, and the Cochrane Database of Systematic Reviews for systematic reviews reporting the effectiveness of CBE published prior to October 29, 2019. The main outcomes assessed were mortality and down staging. The AMSTAR 2 checklist was used to assess the methodological quality of the reviews including risk of bias.
Eleven systematic reviews published between 1993 and 2019 were identified. There was no direct evidence that CBE reduced breast cancer mortality. Indirect evidence suggested that a well-performed CBE achieved the same effect as mammography regarding mortality despite its apparently lower sensitivity (40-69% for CBE vs 77-95% for mammography). Greater sensitivity was recorded among younger and Asian women. Moreover, CBE contributed between 17 and 47% of the shift from advanced to early stage cancer.
CBE merits attention from health system and service planners in LMICs where a national screening programme based on mammography would be prohibitively expensive. In particular, it is likely that considerable value would be gained from conducting implementation scientific research in countries with large numbers of Asian women and/or where younger women are at higher risk.
PROSPERO, registration number CRD42019126798 .
We propose a regression algorithm that utilizes a learned dictionary optimized for sparse inference on a D-Wave quantum annealer. In this regression algorithm, we concatenate the independent and ...dependent variables as a combined vector, and encode the high-order correlations between them into a dictionary optimized for sparse reconstruction. On a test dataset, the dependent variable is initialized to its average value and then a sparse reconstruction of the combined vector is obtained in which the dependent variable is typically shifted closer to its true value, as in a standard inpainting or denoising task. Here, a quantum annealer, which can presumably exploit a fully entangled initial state to better explore the complex energy landscape, is used to solve the highly non-convex sparse coding optimization problem. The regression algorithm is demonstrated for a lattice quantum chromodynamics simulation data using a D-Wave 2000Q quantum annealer and good prediction performance is achieved. The regression test is performed using six different values for the number of fully connected logical qubits, between 20 and 64. The scaling results indicate that a larger number of qubits gives better prediction accuracy.
The integration of renewable energy sources into power systems has gathered significant momentum globally because of its unlimited supply and environmental benefits. Within the portfolio of renewable ...energy, wind power is expected to have a soaring growth rate in the coming years. Despite its well known benefits, wind power poses several challenges in grid integration. The inherent intermittent and non-dispatchable features of wind power not only inject additional fluctuations to the already variable nature of frequency deviation, they also decrease frequency stability by reducing the inertia and the regulation capability. This paper closely examines these effects as well as the effect on tie-line flows and area control error, which causes a larger and longer frequency deviation in the integrated system. Further, the effect of wind power on frequency regulation capability at different penetration levels is also examined. The analytical and simulation results presented here provide some guidance on determining maximum wind power penetration level given a frequency deviation limit.
Urinary tract infections (UTIs) are one of the most common infections in older people and are associated with increased morbidity and mortality. UTIs are also associated with increased risk of ...antimicrobial resistance (AR). This study examined changes in AR among older inpatients with a primary diagnosis of UTIs in the United States over an 8-year period and the impact of AR on clinical outcomes and hospital costs. Data were obtained from the longitudinal hospital HCUP-NIS database from 2009 to 2016 for inpatient episodes that involved those aged 65+ years. The ICD-9 and ICD-10 codes were used to identify episodes with a primary diagnosis of UTIs, comorbidities, AR status and age-adjusted Deyo-Charlson comorbidity index (ACCI) for the patient concerned. Weighted multivariable regression was used to examine the impact of AR on all-cause inpatient mortality, discharge destination, length of stay and hospital expenditures, adjusted for socio-demographic and clinical covariates. The proportion of admissions with AR increased, from 3.64% in 2009 to 6.88% in 2016 (p<0.001), with distinct patterns for different types of resistance. The likelihood of AR was higher in admissions with high ACCI scores and admissions to hospitals in urban areas. Admissions with AR were more likely to be discharged to healthcare facilities (e.g. care homes) compared to routine discharge (OR 1.81; 95%CI, 1.75-1.86), had increased length of stay (1.12 days; 95%CI, 1.06-1.18) and hospital costs (1259 USD; 95%CI, 1178-1340). Resistance due to MRSA was specifically associated with increased hospital mortality (OR 1.33; 95%CI, 1.15-1.53). Our findings suggest that the prevalence of AR has increased among older inpatients with UTIs in the USA. The study highlights the impact of AR among older inpatients with a primary diagnosis of UTIs on clinical outcomes and hospital costs. These relationships and their implications for the care homes to which patients are frequently discharged warrant further research.
Fe
3+
-doped TiO
2
nanoparticles (NPs) were synthesized via the solvothermal method to develop a cost-effective adsorbent for Congo red (CR) removal from aqueous solutions. The synthesized NPs were ...characterized by XRD, FTIR, FE-SEM, EDXS, and nitrogen adsorption isotherms. Results confirmed that the incorporation of Fe
3+
into the TiO
2
lattice effectively decreased the particle size, increased the Brunauer–Emmett–Teller (BET) surface area, and therefore improved the adsorption capacity of TiO
2
doped with Fe
3+
. The anatase nanocrystalline phase with spherical-shaped particles of a mean diameter of 14.8 nm was produced for Fe
3+
-doped TiO
2
. The analysis of nitrogen adsorption isotherms revealed that the BET surface area of TiO
2
doped with Fe
3+
was as high as 194.82 m
2
.g
−1
, which was larger than that of pure TiO
2
(161.36 m
2
.g
−1
). The equilibrium adsorption data were compatible with the Langmuir isotherm model; the maximum adsorption capacity of CR by TiO
2
doped with Fe
3+
reached 400 mg.g
−1
at 30 °C, which was considerably higher than that of pure TiO
2
(238 mg.g
−1
). Moreover, the equilibrium adsorption time of as-synthesized Fe
3+
-doped TiO
2
NPs was significantly shorter than that of other metal oxides nanostructures in previous works, making them excellent candidates for wastewater treatment. Further studies demonstrated that the adsorption of CR onto the TiO
2
doped with Fe
3+
followed a pseudo-second-order kinetic model; the negative values of ∆G° and positive values of ∆H° indicated that the adsorption of CR by TiO
2
doped with Fe
3+
was spontaneous and endothermic in nature.
Graphical Abstract
Abstract
Since 2010, the Genomicus web server is available online at http://genomicus.biologie.ens.fr/genomicus. This graphical browser provides access to comparative genomic analyses in four ...different phyla (Vertebrate, Plants, Fungi, and non vertebrate Metazoans). Users can analyse genomic information from extant species, as well as ancestral gene content and gene order for vertebrates and flowering plants, in an integrated evolutionary context. New analyses and visualization tools have recently been implemented in Genomicus Vertebrate. Karyotype structures from several genomes can now be compared along an evolutionary pathway (Multi-KaryotypeView), and synteny blocks can be computed and visualized between any two genomes (PhylDiagView).
This paper proposes a new method to evaluate the reliability of a wind farm considering the correlation between wind turbine reliability and wind speed. With increasing integration of wind generation ...into the grid, the reliability and stability of the grid are increasingly impacted. Although there are obvious benefits from wind generation, the stochastic nature of wind speed causes several operational challenges. Recent research has shown that wind speeds also impact the failure rates of the turbines, thereby compounding the effect of wind speed variation. The objective of this paper is to evaluate the impact of wind speed on the reliability of a wind farm considering the correlation between wind speed and wind turbine failure rate. The method proposed in this paper is implemented using discrete convolution. The effectiveness of the proposed method is proved by comparing reliability indexes of the modified IEEE RTS-79 system with and without considering the impacts of the negative correlation between wind turbine reliability and wind speed.
We present a new lossy compression algorithm for statistical floating-point data through a representation learning with binary variables. The algorithm finds a set of basis vectors and their binary ...coefficients that precisely reconstruct the original data. The optimization for the basis vectors is performed classically, while binary coefficients are retrieved through both simulated and quantum annealing for comparison. A bias correction procedure is also presented to estimate and eliminate the error and bias introduced from the inexact reconstruction of the lossy compression for statistical data analyses. The compression algorithm is demonstrated on two different datasets of lattice quantum chromodynamics simulations. The results obtained using simulated annealing show 3-3.5 times better compression performance than the algorithm based on neural-network autoencoder. Calculations using quantum annealing also show promising results, but performance is limited by the integrated control error of the quantum processing unit, which yields large uncertainties in the biases and coupling parameters. Hardware comparison is further studied between the previous generation D-Wave 2000Q and the current D-Wave Advantage system. Our study shows that the Advantage system is more likely to obtain low-energy solutions for the problems than the 2000Q.
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