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With the availability of high-dimensional genetic biomarkers, it is of interest to identify heterogeneous effects of these predictors on patients' survival, along with proper statistical inference. Censored quantile regression has emerged as a powerful tool for detecting heterogeneous effects of covariates on survival outcomes. To our knowledge, there is little work available to draw inferences on the effects of high-dimensional predictors for censored quantile regression (CQR). This article proposes a novel procedure to draw inference on all predictors within the framework of global CQR, which investigates covariate-response associations over an interval of quantile levels, instead of a few discrete values. The proposed estimator combines a sequence of low-dimensional model estimates that are based on multi-sample splittings and variable selection. We show that, under some regularity conditions, the estimator is consistent and asymptotically follows a Gaussian process indexed by the quantile level. Simulation studies indicate that our procedure can properly quantify the uncertainty of the estimates in high-dimensional settings. We apply our method to analyze the heterogeneous effects of SNPs residing in lung cancer pathways on patients' survival, using the Boston Lung Cancer Survival Cohort, a cancer epidemiology study on the molecular mechanism of lung cancer. [ABSTRACT FROM AUTHOR]

To avoid fraudulent practices, LC-Orbitrap and FT-NIRS combined with multivariate analysis was used to distinguish between 53 Korean and foreign Boston butt samples; forty were used to establish the calibration model and 13 were used as an external validation set. Twenty metabolites were determined to be good indicators of geographic origin. Both LC-Orbitrap with CDA model based on 20 metabolites and FT-NIRS with PLS achieved 100% efficiency in identifying Korean and foreign samples; overall predictive rates for LC-Orbitrap (94.9%) and FT-NIRS (100%). Thus, combined use of LC-Orbitrap and FT-NIRS could be proposed to determine reliably discriminate geographic origins of pork samples. [ABSTRACT FROM AUTHOR]

Assessment of intraocular pressure (IOP) is a core diagnostic tool in management of glaucoma. All established ways to measure IOP use indirect approaches through ocular tissues, mainly the cornea or the sclera. Telemetric IOP measurement with an implantable device could eliminate bias caused by indirect techniques and could allow continuous monitoring. A favorable safety profile, high efficacy and good tolerability are key requirements. The Eyemate-IO™ system (Implandata Ophthalmic Products GmbH, Hannover, Germany) is a novel CE-marked implantable medical device for direct measurement of IOP. It consists of an intraocular sensor ring and an external reading device. This review presents the mechanism of telemetric IOP measurement and summarizes the available clinical data. Twelve months follow-up data of two clinical trials provide support for the efficacy and safety of this device. The implantable Eyemate-IO™ in keratoprosthesis was well tolerated; recorded adverse events were known complications of standalone surgery. The system had a good agreement with other IOP measuring modalities, including intraoperative manometry. In glaucoma patients, the Eyemate-IO™ could be implanted safely and showed a favorable efficacy and safety profile in the first twelve months postoperatively. The potential to achieve IOP monitoring with the Eyemate-IO™ seems promising. [ABSTRACT FROM AUTHOR]

Introduction: Since the introduction of burst spinal cord stimulation for neuropathic pain, several companies have developed their own version of burst stimulation, which is confusing the marketplace and clinicians of what burst stimulation truly is, the value and utilization of the therapy. Areas covered: We review those two burst stimulation designs and notice important differences. The original burstDRTM stimulation tries to mimic physiologic burst firing, which involves closely spaced high frequency sodium spikes nested on a calcium mediated plateau. This is realized by generating a train of 5 monophasic spikes of increasing amplitude with passive charge balance after the last spike, in contrast to the other burst designs which involve a version of cycling 4–5 spikes each being individually actively charge balanced spikes. Expert opinion: Based on the neurobiology of burst firing as well as abductive reasoning we like to clarify that burstDRTM is a true physiologic burst stimulation, and that other versions being called burst stimulation are essentially clustered tonic stimulation. This differentiating terminology will prevent confusion for healthcare providers, regulators, and the marketplace of what burst stimulation is. [ABSTRACT FROM AUTHOR]

The US Environmental Protection Agency (EPA) has taken major steps to meet the targets of the Social Cost of Carbon (SC-CO2). In what follows, a research model using the market price for emission allowances per metric ton illustrates how the economic and environment mechanisms of carbon price can be formulated using deterministic and stochastic equilibrium models: the primary concern becomes one of optimal stochastic control. Moreover, this framework allows us to consider the prospective influence of the proposed policy on the profit margins for remanufactured goods, in addition to its performance; further presented is an in-depth study to quantitatively evaluate the model and its performance through the use of Orthogonal Arrays. The results demonstrate that the proposed policy for carbon tax brings about tight constraints on the quantity of carbon emissions produced through supply chain operations; numerical examples are based upon actual locations in the area of Boston. [ABSTRACT FROM AUTHOR]