75 research outputs found

    Composite Iterative Algorithm and Architecture for q-th Root Calculation

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    An algorithm for the q-th root extraction, being q any integer, is presented in this paper. The algorithm is based on an optimized implementation of X^{1/q} by a sequence of parallel and/or overlapped operations: (1) reciprocal, (2) digit-recurrence logarithm, (3) left-to-right carry-free multiplication and (4) on-line exponential. A detailed error analysis and two architectures are proposed, for low precision q and for higher precision q. The execution time and hardware requirements are estimated for single and double precision floating-point computations for several radices; this helps to determine which radices result in the most efficient implementations. The architectures proposed improve the features of other architectures for q-th root extraction.Dans cet article, nous présentons un algorithme matériel pour l'extraction de la racine q-ième d'un nombre X, où q est un entier naturel non nul. Cet algorithme est basé sur une implantation optimisée de la fonction X^{1/q} par une séquence d'opérations parallèles et/ou superposées: (1) réciproque, (2) logarithme chiffre par chiffre, (3) multiplication de gauche-à-droite sans propagation de retenue et (4) exponentielle en ligne. Une analyse détaillée des erreurs et deux architectures sont proposées, pour q de basse précision et pour q de précision plus haute. Le temps d'exécution et les composants matériels à utiliser sont estimés pour des calculs en virgule flottante simple et double précision et pour plusieurs bases. Cette étude aide à déterminer quelles bases mènent aux implantations les plus efficaces. Les architectures proposées améliorent les caractéristiques d'architectures précédentes destinées à l'extraction des racines

    High-Speed FPGA Architecture for CABAC Decoding Acceleration in H.264/AVC Standard

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    This is a post-peer-review, pre-copyedit version of an article published in Journal of Signal Processing Systems. The final authenticated version is available online at: https://doi.org/10.1007/s11265-012-0718-y.[Abstract] Video encoding and decoding are computing intensive applications that require high performance processors or dedicated hardware. Video decoding offers a high parallel processing potential that may be exploited. However, a particular task challenges parallelization: entropy decoding. In H.264 and SVC video standards, this task is mainly carried out using arithmetic decoding, an strictly sequential algorithm that achieves results close to the entropy limit. By accelerating arithmetic decoding, the bottleneck is removed and parallel decoding is enabled. Many works have been published on accelerating pure binary encoding and decoding. However, little research has been done into how to integrate binary decoding with context managing and control without losing performance. In this work we propose a FPGA-based architecture that achieves real time decoding for high-definition video by sustaining a 1 bin per cycle throughput. This is accomplished by implementing fast bin decoding; a novel and area efficient context-managing mechanism; and optimized control scheduling.Ministerio de Ciencia e Innovación; TIN2010-17541Xunta de Galicia, Consellería de Cultura, Educación e Ordenación Universitaria; 2010/6Xunta de Galicia, Consellería de Cultura, Educación e Ordenación Universitaria; 2010/28

    High-Speed Function Approximation using a Minimax Quadratic Interpolator

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    A table-based method for high-speed function approximation in single-precision floating-point format is presented in this paper. Our focus is the approximation of reciprocal, square root, square root reciprocal, exponentials, logarithms, trigonometric functions, powering (with a fixed exponent p), or special functions. The algorithm presented here combines table look-up, an enhanced minimax quadratic approximation, and an efficient evaluation of the second-degree polynomial (using a specialized squaring unit, redundant arithmetic, and multioperand addition). The execution times and area costs of an architecture implementing our method are estimated, showing the achievement of the fast execution times of linear approximation methods and the reduced area requirements of other second-degree interpolation algorithms. Moreover, the use of an enhanced minimax approximation which, through an iterative process, takes into account the effect of rounding the polynomial coefficients to a finite size allows for a further reduction in the size of the look-up tables to be used, making our method very suitable for the implementation of an elementary function generator in state-of-the-art DSPs or graphics processing units (GPUs)

    Dyes As Fungal Inhibitors : effect on Colony Diameter

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    The effects of a wide range of concentrations of 13 dyes on the colony diameters of nine fungal strains (including members of the Deuteromycetes and Zygomycetes) were evaluated. Auramine at a concentration of 50 ppm (50 ,ug/ml), methylene blue at a concentration of 500 ppm, gentian violet at a concentration of 5 ppm, and phenol red at a concentration of 50 ppm performed as well as the commonly used dyes dichloran at a concentration of 2 ppm and rose bengal at a concentration of 50 ppm in that they allowed adequate colony development of the Deuteromycetes strains tested and controlled rapidly spreading fungi

    Efficacy and safety of intermittent intravenous outpatient administration of levosimendan in patients with advanced heart failure: the LION-HEART multicentre randomised trial

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    Aims. The LION‐HEART study was a multicentre, double‐blind, randomised, parallel‐group, placebo‐controlled trial evaluating the efficacy and safety of intravenous administration of intermittent doses of levosimendan in outpatients with advanced chronic heart failure. Methods and results. Sixty‐nine patients from 12 centres were randomly assigned at a 2:1 ratio to levosimendan or placebo groups, receiving treatment by a 6‐hour intravenous infusion (0.2 μg/kg/min without bolus) every 2 weeks for 12 weeks. The primary endpoint was the effect on serum concentrations of N‐terminal pro‐B‐type natriuretic peptide (NT‐proBNP) throughout the treatment period in comparison with placebo. Secondary endpoints included evaluation of safety, clinical events and health‐related quality of life (HRQoL). The area under the curve (AUC, pg.day/mL) of the levels of NT‐proBNP over time for patients who received levosimendan was significantly lower than for the placebo group (344 × 103 [95% Confidence Interval (CI) 283 × 103−404 × 103] vs. 535 × 103 [443 × 103−626 × 103], p = 0.003). In comparison with the placebo group, the patients on levosimendan experienced a reduction in the rate of heart failure hospitalisation (hazard ratio 0.25; 95% CI 0.11-0.56; P = 0.001). Patients on levosimendan were less likely to experience a clinically significant decline in HRQoL over time (P = 0.022). Adverse event rates were similar in the two treatment groups. Conclusions. In this small pilot study, intermittent administration of levosimendan to ambulatory patients with advanced systolic heart failure reduced plasma concentrations of NT‐proBNP, worsening of HRQoL and hospitalisation for heart failure. The efficacy and safety of this intervention should be confirmed in larger trials

    A histologic scoring system for prognosis of patients with Alcoholic hepatitis

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    BACKGROUND & AIMS: There is no histologic classification system to determine prognoses of patients with alcoholic hepatitis (AH). We identified histologic features associated with disease severity and created a histologic scoring system to predict short-term (90-day) mortality. METHODS: We analyzed data from 121 patients admitted to the Liver Unit (Hospital Clinic, Barcelona, Spain) from January 2000 to January 2008 with features of AH and developed a histologic scoring system to determine the risk of death using logistic regression. The system was tested and updated in a test set of 96 patients from 5 academic centers in the United States and Europe, and a semiquantitative scoring system called the Alcoholic Hepatitis Histologic Score (AHHS) was developed. The system was validated in an independent set of 109 patients. Interobserver agreement was evaluated by weighted κ statistical analysis. RESULTS: The degree of fibrosis, degree of neutrophil infiltration, type of bilirubinostasis, and presence of megamitochondria were independently associated with 90-day mortality. We used these 4 parameters to develop the AHHS to identify patients with a low (0-3 points), moderate (4-5 points), or high (6-9 points) risk of death within 90 days (3%, 19%, and 51%, respectively; P < .0001). The AHHS estimated 90-day mortality in the training and test sets with an area under the receiver operating characteristic value of 0.77 (95% confidence interval, 0.71-0.83). Interrater agreement values were 0.65 for fibrosis, 0.86 for bilirubinostasis, 0.60 for neutrophil infiltration, and 0.46 for megamitochondria. Interestingly, the type of bilirubinostasis predicted the development of bacterial infections. CONCLUSIONS: We identified histologic features associated with the severity of AH and developed a patient classification system that might be used in clinical decision making

    Associations of hypomagnesemia in patients seeking a first treatment of alcohol use disorder

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    Introduction: Hypomagnesemia (hypoMg) has not yet been extensively studied in alcohol use disorder (AUD) . We hypothesize that chronic, excessive alcohol consumption favors oxidative stress and pro-inflammatory alterations that may be exacerbated by hypoMg. The objective of this study was to analyze the prevalence and associations of hypoMg in AUD.Patients and Methods: Cross-sectional study in patients admitted for a first treatment of AUD in six tertiary centers between 2013 and 2020. Socio-demographic, alcohol use characteristics, and blood parameters were ascertained at admission.Results: 753 patients (71% men) were eligible; age at admission was 48 years [IQR, 41-56 years]. Prevalence of hypoMg was 11.2%, higher than that observed for hypocalcemia (9.3%), hyponatremia (5.6%), and hypokalemia (2.8%). HypoMg was associated with older age, longer duration of AUD, anemia, higher erythrocyte sedimen-tation rate, gamma-glutamyl transpeptidase, glucose levels, advanced liver fibrosis (FIB-4 >= 3.25) and estimated glomerular filtration rate (eGFR) < 60 mL/min. In multivariate analysis, advanced liver fibrosis (OR, 8.91; 95% CI, 3.3-23.9) and eGFR < 60 mL (OR, 5.2; 95% CI, 1.0-26.2) were the only factors associated with hypoMg.Conclusions: Mg deficiency in AUD is associated with liver damage and glomerular dysfunction suggesting that both comorbidities should be assessed in the course of serum hypoMg

    Comparative study of paediatric prescription drug utilization between the spanish and immigrant population

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    <p>Abstract</p> <p>Background</p> <p>The immigrant population has increased greatly in Spain in recent years to the point where immigrants made up 12% of the infant population in 2008. There is little information available on the profile of this group with regard to prescription drug utilization in universal public health care systems such as that operating in Spain. This work studies the overall and specific differences in prescription drug utilization between the immigrant and Spanish population.</p> <p>Methods</p> <p>Use was made of the Aragonese Health Service databases for 2006. The studied population comprises 159,908 children aged 0-14 years, 13.6% of whom are foreign nationals. Different utilization variables were calculated for each group. Prescription-drug consumption is measured in Defined Daily Doses (DDD) and DDD/1000 persons/day/(DID).</p> <p>Results</p> <p>A total of 833,223 prescriptions were studied. Utilization is lower for immigrant children than in Spanish children for both DID (66.27 v. 113.67) and average annual expense (€21.55 v. €41.14). Immigrant children consume fewer prescription drugs than Spanish children in all of the therapy groups, with the most prescribed (in DID) being: respiratory system, anti-infectives for systemic use, nervous system, sensory organs. Significant differences were observed in relation to the type of drugs and the geographical background of immigrants.</p> <p>Conclusion</p> <p>Prescription drug utilization is much greater in Spanish children than in immigrant children, particularly with reference to bronchodilators (montelukast and terbutaline) and attention-disorder hyperactivity drugs such as methylphenidate. There are important differences regarding drug type and depending on immigrants' geographical backgrounds that suggest there are social, cultural and access factors underlying these disparities.</p

    Strategies to reengage patients lost to follow up in HIV care in high income countries, a scoping review

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    Background: Despite remarkable achievements in antiretroviral therapy (ART), losses to follow-up (LTFU) might prevent the long-term success of HIV treatment and might delay the achievement of the 90-90-90 objectives. This scoping review is aimed at the description and analysis of the strategies used in high-income countries to reengage LTFU in HIV care, their implementation and impact. Methods: A scoping review was done following Arksey & O'Malley's methodological framework and recommendations from Joanna Briggs Institute. Peer reviewed articles were searched for in Pubmed, Scopus and Web of Science; and grey literature was searched for in Google and other sources of information. Documents were charted according to the information presented on LTFU, the reengagement procedures used in HIV units in high-income countries, published during the last 15 years. In addition, bibliographies of chosen articles were reviewed for additional articles. Results: Twenty-eight documents were finally included, over 80% of them published in the United States later than 2015. Database searches, phone calls and/or mail contacts were the most common strategies used to locate and track LTFU, while motivational interviews and strengths-based techniques were used most often during reengagement visits. Outcomes like tracing activities efficacy, rates of reengagement and viral load reduction were reported as outcome measures. Conclusions: This review shows a recent and growing trend in developing and implementing patient reengagement strategies in HIV care. However, most of these strategies have been implemented in the United States and little information is available for other high-income countries. The procedures used to trace and contact LTFU are similar across reviewed studies, but their impact and sustainability are widely different depending on the country studied
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