140 research outputs found

    Low-rank SIFT: An Affine Invariant Feature for Place Recognition

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    In this paper, we present a novel affine-invariant feature based on SIFT, leveraging the regular appearance of man-made objects. The feature achieves full affine invariance without needing to simulate over affine parameter space. Low-rank SIFT, as we name the feature, is based on our observation that local tilt, which are caused by changes of camera axis orientation, could be normalized by converting local patches to standard low-rank forms. Rotation, translation and scaling invariance could be achieved in ways similar to SIFT. As an extension of SIFT, our method seeks to add prior to solve the ill-posed affine parameter estimation problem and normalizes them directly, and is applicable to objects with regular structures. Furthermore, owing to recent breakthrough in convex optimization, such parameter could be computed efficiently. We will demonstrate its effectiveness in place recognition as our major application. As extra contributions, we also describe our pipeline of constructing geotagged building database from the ground up, as well as an efficient scheme for automatic feature selection

    Burden of Atopic Dermatitis in the United States: Analysis of Healthcare Claims Data in the Commercial, Medicare, and Medi-Cal Databases

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    Comparative data on the burden of atopic dermatitis (AD) in adults relative to the general population are limited. We performed a large-scale evaluation of the burden of disease among US adults with AD relative to matched non-AD controls, encompassing comorbidities, healthcare resource utilization (HCRU), and costs, using healthcare claims data. The impact of AD disease severity on these outcomes was also evaluated

    An Anchor-Point Based Image-Model for Room Impulse Response Simulation with Directional Source Radiation and Sensor Directivity Patterns

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    The image model method has been widely used to simulate room impulse responses and the endeavor to adapt this method to different applications has also piqued great interest over the last few decades. This paper attempts to extend the image model method and develops an anchor-point-image-model (APIM) approach as a solution for simulating impulse responses by including both the source radiation and sensor directivity patterns. To determine the orientations of all the virtual sources, anchor points are introduced to real sources, which subsequently lead to the determination of the orientations of the virtual sources. An algorithm is developed to generate room impulse responses with APIM by taking into account the directional pattern functions, factional time delays, as well as the computational complexity. The developed model and algorithms can be used in various acoustic problems to simulate room acoustics and improve and evaluate processing algorithms.Comment: 19 pages, 8 figure

    Risk of Ocular Complications in Patients with Noninfectious Intermediate Uveitis, Posterior Uveitis, or Panuveitis

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    PurposeNoninfectious uveitis results in vision loss and ocular complications without adequate treatment. We compared the risk of developing ocular complications between patients with noninfectious intermediate uveitis, posterior uveitis, or panuveitis (NIIPPU) and matched controls.DesignRetrospective analysis of insurance claims data (OptumHealth, Eden Prairie, MN; January 1, 1998–March 31, 2012).ParticipantsCases 18 to 64 years of age with 2 or more NIIPPU diagnoses (International Classification of Diseases, 9th Revision, Clinical Modification codes) were matched 1:1 by sex, age, region, company, employment status, and index date with controls without uveitis. Patients with an ocular complication during baseline were excluded.MethodsContinuous eligibility for 6 months or more before the first NIIPPU diagnosis date was required. Risks of ocular complications developing during patients' continuous eligibility in the study period were compared using unadjusted Kaplan-Meier survival analysis to estimate risk of and time to complications and adjusted Cox regression analysis to estimate hazard ratios (HRs).Main Outcome MeasuresPercentages of cases and controls who demonstrate ocular complications and 1-, 5-, and 10-year risks and HRs for each complication.ResultsMean age of the 1769 cases and matched controls was 47 years and 47% were men; 302 cases had persistent NIIPPU. During the study period, NIIPPU cases had a higher risk of any ocular complication (P < 0.001); the 5-year risk of any ocular complication was 66% for patients versus 24% for controls. Specifically, NIIPPU patients had greater 5-year risks of glaucoma (20% vs. 9%), cataract (35% vs. 13%), visual disturbance (29% vs. 9%), blindness or low vision (5% vs. 0.5%), retinal detachment (11% vs. 0.8%), and retinal disorder (28% vs. 2%) compared with controls. Hazard ratios indicated greater risks of ocular complications in cases versus controls during the overall observation period (HR, 5.2 for any ocular complication; HR, 4.8 for visual disturbance; HR, 3.2 for cataract; and HR, 2.7 for glaucoma; all P < 0.001). Hazard ratios for persistent cases indicated even greater risks.ConclusionsNoninfectious intermediate uveitis, posterior uveitis, or panuveitis, particularly persistent disease, is associated with a substantial risk of ocular complications. Optimal treatment initiatives remain imperative to reduce the ocular complication–related burden of NIIPPU

    Direct and indirect resource use, healthcare costs and work force absence in patients with non-infectious intermediate, posterior or panuveitis

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    PURPOSE: To ascertain resource use, costs and risk of workforce absence in non‐infectious uveitis cases versus matched controls. METHODS: In a retrospective claims analysis of employees in the United States, prevalent (N = 705) and incident (N = 776) cases 18–64 years old with ≥2 diagnoses of non‐infectious intermediate, posterior or panuveitis were matched 1:1 to controls without uveitis. Persistent prevalent cases (treated for ≥90 days, N = 112) also were analysed. Outcomes were annual direct resource use and costs associated with inpatient stays; emergency department, outpatient and ophthalmologist/optometrist visits; and prescription drugs. Indirect resource use and costs associated with work loss from disability and medically related absenteeism also were compared. Multivariate regression assessed cost differences between cases and controls. RESULTS: Cases had significantly (p < 0.05) more medical resource use versus controls including 0.4 versus 0.2 emergency visits and 16.5 versus 7.6 outpatient/other visits. Cases used more prescription drugs (7.8 versus 4.1) and had more disability days (10.3 versus 4.6), medically related absenteeism days (8.5 versus 3.8), and work loss days (18.7 versus 8.4) than controls (all p < 0.05). Total direct (12 940versus12 940 versus 3730) and indirect (3144versus3144 versus 1378) costs were higher in cases than controls (all p < 0.05). Results for persistent cases suggested greater utilization and associated cost and work loss burden. Compared with controls, cases had significantly greater risks of workforce absence, leave of absence and long‐term disability (all p < 0.05). CONCLUSION: Non‐infectious intermediate, posterior or panuveitis, particularly persistent disease, is associated with substantial medical and work loss costs suggesting an unmet need for more effective treatments

    Dupilumab Improves Nasal Polyp Burden and Asthma Control in Patients With CRSwNP and AERD

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    In the difficult-to-treat subgroup of patients with chronic rhinosinusitis with nasal polyps (CRSwNP) and comorbid aspirin-exacerbated respiratory disease, dupilumab significantly improved CRSwNP disease outcomes, along with asthma control and lung function. This is preliminary evidence of the effect of dupilumab in patients with CRSwNP and comorbid aspirin- exacerbated respiratory disease

    Effect of Adalimumab on Work Productivity and Indirect Costs in Moderate to Severe Crohn’s Disease: A Meta-Analysis

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    peer reviewedOBJECTIVE: To assess the effect of adalimumab on work productivity and indirect costs in patients with Crohn's disease (CD) using a meta-analysis of clinical trials. METHODS: Study-level results were pooled from all clinical trials of adalimumab for moderate to severe CD in which work productivity outcomes were evaluated. Work Productivity and Activity Impairment Questionnaire outcomes (absenteeism, presenteeism and total work productivity impairment [TWPI]) were extracted from adalimumab trials. Meta-analyses were used to estimate pooled averages and 95% CIs of one-year accumulated reductions in work productivity impairment with adalimumab. Pooled averages were multiplied by the 2008 United States national average annual salary (44,101)toestimateperpatientindirectcostsavingsduringtheyearfollowingadalimumabinitiation.RESULTS:Thefourincludedtrials(ACCESS,CARE,CHOICEandEXTEND)representedatotalof1202employedadalimumabtreatedpatientsatbaseline.Eachstudyfollowedpatientsforaminimumof20weeks.Pooledestimates(9544,101) to estimate per-patient indirect cost savings during the year following adalimumab initiation. RESULTS: The four included trials (ACCESS, CARE, CHOICE and EXTEND) represented a total of 1202 employed adalimumab-treated patients at baseline. Each study followed patients for a minimum of 20 weeks. Pooled estimates (95% CIs) of one-year accumulated work productivity improvements were as follows: -9% (-10% to -7%) for absenteeism; -22% (-26% to -18%) for presenteeism; and -25% (-30% to -20%) for TWPI. Reductions in absenteeism and TWPI translated into per-patient indirect cost savings (95% CI) of 3,856 (3,183to3,183 to 4,529) and 10,964(10,964 (8,833 to $13,096), respectively. CONCLUSION: Adalimumab provided clinically meaningful improvements in work productivity among patients with moderate to severe CD, which may translate into substantial indirect cost savings from an employer's perspective

    Reducing the Uncertainty in Estimating Soil Microbial-Derived Carbon Storage

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    Soil organic carbon (SOC) is the largest carbon pool in terrestrial ecosystems and plays a crucial role in mitigating climate change and enhancing soil productivity. Microbial-derived carbon (MDC) is the main component of the persistent SOC pool. However, current formulas used to estimate the proportional contribution of MDC are plagued by uncertainties due to limited sample sizes and the neglect of bacterial group composition effects. Here, we compiled the comprehensive global dataset and employed machine learning approaches to refine our quantitative understanding of MDC contributions to total carbon storage. Our efforts resulted in a reduction in the relative standard errors in prevailing estimations by an average of 71% and minimized the effect of global variations in bacterial group compositions on estimating MDC. Our estimation indicates that MDC contributes approximately 758 Pg, representing approximately 40% of the global soil carbon stock. Our study updated the formulas of MDC estimation with improving the accuracy and preserving simplicity and practicality. Given the unique biochemistry and functioning of the MDC pool, our study has direct implications for modeling efforts and predicting the land-atmosphere carbon balance under current and future climate scenarios
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