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External quality assessment in the absence of proficiency testing: a split-sample testing program experience.

Clin Biochem 2021 Jul 27. Epub 2021 Jul 27.

Quality Department. Biomedical Diagnostic Center. Hospital Clínic of Barcelona.

In the field of laboratory medicine, proficiency testing is a vehicle used to improve the reliability of reported results. When proficiency tests are unavailable for a given analyte, an alternative approach is required to ensure adherence to the International Organization for Standardization (ISO) 15189:2012 standard. In this study, we report the results of a split-sample testing program performed as an alternative to a formal PT. Read More

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A novel application of simple submersible yeast-based microbial fuel cells as dissolved oxygen sensors in environmental waters.

Enzyme Microb Technol 2021 Sep 15;149:109831. Epub 2021 May 15.

Solar Energy Research Institute, Universiti Kebangsaan Malaysia, 43600, Bangi, Selangor, Malaysia; Research Centre for Electrical Power and Mechatronics, Indonesian Institute of Sciences (LIPI), Bandung, Indonesia. Electronic address:

In this study, yeast microbial fuel cells (MFCs) were established as biosensors for in-situ monitoring of dissolved oxygen (DO) levels in environmental waters, with yeast and glucose substrates acting as biocatalyst and fuel, respectively. Diverse environmental factors, such as temperature, pH and conductivity, were considered. The sensor performance was first tested with distilled water with different DO levels ranging from 0 mg/L to 8 mg/L and an external resistance of 1000 Ω. Read More

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September 2021

Cerebellar and Cortical Correlates of Internal and External Speech Error Monitoring.

Cereb Cortex Commun 2021 31;2(2):tgab038. Epub 2021 May 31.

Aix-Marseille Université, CNRS, LPC 13331, Marseille, France.

An event-related functional magnetic resonance imaging study examined how speakers inspect their own speech for errors. Concretely, we sought to assess 1) the role of the temporal cortex in monitoring speech errors, linked with comprehension-based monitoring; 2) the involvement of the cerebellum in internal and external monitoring, linked with forward modeling; and 3) the role of the medial frontal cortex for internal monitoring, linked with conflict-based monitoring. In a word production task priming speech errors, we observed enhanced involvement of the right posterior cerebellum for trials that were correct, but on which participants were more likely to make a word as compared with a nonword error (contrast of internal monitoring). Read More

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Skipping a Beat: Heartbeat-Evoked Potentials Reflect Predictions during Interoceptive-Exteroceptive Integration.

Cereb Cortex Commun 2020 1;1(1):tgaa060. Epub 2020 Sep 1.

School of Psychology and Centre for Human Brain Health, University of Birmingham, Edgbaston B15 2TT, UK.

Several theories propose that emotions and self-awareness arise from the integration of internal and external signals and their respective precision-weighted expectations. Supporting these mechanisms, research indicates that the brain uses temporal cues from cardiac signals to predict auditory stimuli and that these predictions and their prediction errors can be observed in the scalp heartbeat-evoked potential (HEP). We investigated the effect of precision modulations on these cross-modal predictive mechanisms, via attention and interoceptive ability. Read More

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September 2020

Future and past autobiographical memory in persons with HIV disease.

Neuropsychology 2021 Jul 22;35(5):461-471. Epub 2021 Apr 22.

Department of Psychology, University of Houston.

While HIV disease is associated with impairment in declarative memory, the ability of people with HIV (PWH) to describe past and future autobiographical events is not known. Participants included 63 PWH and 28 seronegative individuals ages 50-78 who completed standardized neurocognitive and everyday functioning assessments. Participants described four events from the recent past and four imagined events in the near future, details from which were classified as internal or external to the main event. Read More

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Validation of Methods for Estimation of Knee Joint Mechanical Impedance During Locomotion Using a Torque-Controllable Knee Exoskeleton.

J Biomech Eng 2021 Jul 21. Epub 2021 Jul 21.

Dept. of Mechanical Engineering, Robotics Institute, University of Michigan, Ann Arbor, Michigan 48109.

The mechanical impedance of the joints of the leg govern the body's response to external disturbances, and its regulation is essential for the completion of tasks of daily life. However, it is still unclear how this quantity is regulated at the knee during dynamic tasks. In this work, we introduce a method to estimate the mechanical impedance of spring-mass systems using a torque-controllable exoskeleton with the intention of extending these methods to characterize the mechanical impedance of the human knee during locomotion. Read More

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Learning to fly: thermochemistry of energetic materials by modified thermogravimetric analysis and highly accurate quantum chemical calculations.

Phys Chem Chem Phys 2021 Jul;23(29):15522-15542

Semenov Federal Research Center for Chemical Physics, RAS, 4 Kosygina Str., 119991 Moscow, Russia. and Novosibirsk State University, 1 Pirogova Str., 630090 Novosibirsk, Russia and Institute of Chemical Kinetics and Combustion, SB RAS, 3 Institutskaya Str., 630090 Novosibirsk, Russia.

The standard state enthalpy of formation and the enthalpy of sublimation are essential thermochemical parameters determining the performance and application prospects of energetic materials (EM). Direct experimental measurements of these properties are complicated by low volatility and high heat release in bomb calorimetry experiments. As a result, the uncertainties in the reported enthalpies of formation for a number of even well-known CHNO-containing compounds might amount up to tens kJ mol-1, while for some novel high-nitrogen molecules they reach even hundreds of kJ mol-1. Read More

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Norms for Automatic Estimation of Hippocampal Atrophy and a Step Forward for Applicability to the Italian Population.

Front Neurosci 2021 28;15:656808. Epub 2021 Jun 28.

Laboratory of Neuroinformatics, IRCCS Istituto Centro San Giovanni di Dio Fatebenefratelli, Brescia, Italy.

Introduction: Hippocampal volume is one of the main biomarkers of Alzheimer's Dementia (AD). Over the years, advanced tools that performed automatic segmentation of Magnetic Resonance Imaging (MRI) T13D scans have been developed, such as FreeSurfer (FS) and ACM-Adaboost (AA). Hippocampal volume is considered abnormal when it is below the 5th percentile of the normative population. Read More

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Insights into the molecular properties underlying antibacterial activity of prenylated (iso)flavonoids against MRSA.

Sci Rep 2021 Jul 9;11(1):14180. Epub 2021 Jul 9.

Laboratory of Food Chemistry, Wageningen University & Research, Wageningen, The Netherlands.

High resistance towards traditional antibiotics has urged the development of new, natural therapeutics against methicillin-resistant Staphylococcus aureus (MRSA). Prenylated (iso)flavonoids, present mainly in the Fabaceae, can serve as promising candidates. Herein, the anti-MRSA properties of 23 prenylated (iso)flavonoids were assessed in-vitro. Read More

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Causal inference gates corticostriatal learning.

J Neurosci 2021 Jul 9. Epub 2021 Jul 9.

Department of Psychology, University of California, Riverside, 92521.

Attributing outcomes to your own actions or to external causes is essential for appropriately learning which actions lead to reward and which actions do not. Our previous work showed that this type of credit assignment is best explained by a Bayesian reinforcement learning model which posits that beliefs about the causal structure of the environment modulate reward prediction errors (RPEs) during action value updating. In this study, we investigated the brain networks underlying reinforcement learning that are influenced by causal beliefs using functional magnetic resonance imaging (fMRI) while human participants (n = 31; 13 males, 18 females) completed a behavioral task that manipulated beliefs about causal structure. Read More

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Adaptive nonsingular fixed-time sliding mode control for uncertain robotic manipulators under actuator saturation.

ISA Trans 2021 May 25. Epub 2021 May 25.

CAS Key Laboratory of On-orbit Manufacturing and Integration for Space Optics System, Changchun Institute of Optics, Fine Mechanics and Physics, Chinese Academy of Sciences, Changchun 130033, China; University of Chinese Academy of Sciences, Beijing 100049, China; Institute of Applied Physics, Friedrich-Schiller-University Jena, Max-Wien-Platz 1, 07743 Jena, Germany.

This paper describes an adaptive nonsingular fixed-time sliding mode control (ANFSMC) scheme under actuator saturation that can track the trajectory of a robotic manipulator under external disturbances and inertia uncertainties. First, a novel NFSMC that offers rapid convergence and avoids singularities is proposed for ensuring robotic manipulators global approximate fixed-time convergence. An ANFSMC is then developed for which the bound of the coupling uncertainty is not necessary to know in advance. Read More

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External validation of the Medication Risk Score in polypharmacy patients in general practice: A tool for prioritizing patients at greatest risk of potential drug-related problems.

Basic Clin Pharmacol Toxicol 2021 Jul 8. Epub 2021 Jul 8.

Department of Clinical Pharmacology, Aarhus University Hospital, Aarhus, Denmark.

Drug-related problems are important causes of patient harm and increased healthcare costs. To assist general practitioners in prioritizing patients in need of a critical medication review, we aimed to assess the ability of the Medication Risk Score (MERIS) to stratify patients with polypharmacy in general practice according to their risk of drug-related problems. We conducted a cross-sectional multi-centre external validation study. Read More

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Adaptive Neural-Network-Based Fault-Tolerant Control for a Flexible String With Composite Disturbance Observer and Input Constraints.

IEEE Trans Cybern 2021 Jul 7;PP. Epub 2021 Jul 7.

We propose an adaptive neural-network-based fault-tolerant control scheme for a flexible string considering the input constraint, actuator gain fault, and external disturbances. First, we utilize a radial basis function neural network to compensate for the actuator gain fault. In addition, an observer is used to handle composite disturbances, including unknown approximation errors and boundary disturbances. Read More

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Effects of MR imaging time reduction on substitute CT generation for prostate MRI-only treatment planning.

Phys Eng Sci Med 2021 Jul 6. Epub 2021 Jul 6.

Liverpool and Macarthur Cancer Therapy Centres and Ingham Institute, Sydney, NSW, Australia.

The introduction of MRI linear accelerators (MR-linacs) and the increased use of MR imaging in radiotherapy, requires improved approaches to MRI-only radiotherapy. MRI provides excellent soft tissue visualisation but does not provide any electron density information required for radiotherapy dose calculation, instead MRI is registered to CT images to enable dose calculations. MRI-only radiotherapy eliminates registration errors and reduces patient discomfort, workload and cost. Read More

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A Basic Model to Predict Enteric Methane Emission from Dairy Cows and Its Application to Update Operational Models for the National Inventory in Norway.

Animals (Basel) 2021 Jun 25;11(7). Epub 2021 Jun 25.

Department of Animal and Aquacultural Sciences, Norwegian University of Life Sciences, 1432 Ås, Norway.

The aim of this study was to develop a basic model to predict enteric methane emission from dairy cows and to update operational calculations for the national inventory in Norway. Development of basic models utilized information that is available only from feeding experiments. Basic models were developed using a database with 63 treatment means from 19 studies and were evaluated against an external database ( = 36, from 10 studies) along with other extant models. Read More

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Multiple, random spot urine sampling for estimating urinary sodium excretion.

Eur J Pediatr 2021 Jul 1. Epub 2021 Jul 1.

, Bergamo, Italy.

The measurement of sodium intake may be important for the management of hypertension. Dietary surveys and 24-h urinary collection are often unreliable and/or impractical. We hypothesized that urinary sodium excretion can be accurately estimated through multiple spot urine samples from different days. Read More

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Cognitive biases cloud our clinical decisions and patient expectations: a narrative review to help bridge the gap between evidence-based and personalized medicine.

Ann Phys Rehabil Med 2021 Jun 26:101551. Epub 2021 Jun 26.

Swiss Olympic Medical Center, Sport Medicine Unit, Lausanne University Hospital, Lausanne, Switzerland; Institute of Sport Sciences, University of Lausanne, Lausanne, Switzerland.

In sports medicine and rehabilitation of musculoskeletal conditions, training, knowledge and expertise of clinicians are the guarantors of good clinical practice. But are they really? Since the 1970s, a growing body of sociological and behavioral science has developed the concepts of cognitive biases and thinking errors. In a nutshell, it tries to explain how we approach decision-making using shortcuts, or heuristics. Read More

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[Finite element method simulating bursting process of multi-chamber flexible package infusion bag].

Sheng Wu Yi Xue Gong Cheng Xue Za Zhi 2021 Jun;38(3):556-562

Sichuan Kelun Pharmaceutical Co.Ltd, Chengdu 610500, P.R.China.

This study aims to overcome the shortcomings such as low efficiency, high cost and difficult to carry out multi-parameter research, which limited the optimization of infusion bag configuration and manufacture technique by experiment method. We put forward a fluid cavity based finite element method, and it could be used to simulate the stress distribution and deformation process of infusion bag under external load. In this paper, numerical models of infusion bag with different sizes was built, and the fluid-solid coupling deformation process was calculated using the fluid cavity method in software ABAQUS subject to the same boundary conditions with the burst test. Read More

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Imputing intracluster correlation coefficients from a posterior predictive distribution is a feasible method of dealing with unit of analysis errors in a meta-analysis of cluster RCTs.

J Clin Epidemiol 2021 Jun 22. Epub 2021 Jun 22.

Clinical Epidemiology Program, Ottawa Hospital Research Institute, Ottawa, Canada; School of Epidemiology and Public Health, University of Ottawa, Ottawa, Canada; Department of Medicine, University of Ottawa, Ottawa, Canada.

Background: Incorporating cluster randomized trials (CRTs) into meta-analyses is challenging because appropriate standard errors of study estimates accounting for clustering are not always reported. Systematic reviews of CRTs often use a single constant external estimate of the intraclass correlation coefficient (ICC) to adjust study estimate standard errors and facilitate meta-analyses; an approach that fails to account for possible variation of ICCs among studies and the imprecision with which they are estimated. Using a large systematic review of the effects of diabetes quality improvement interventions, we investigated whether we could better account for ICC variation and uncertainty in meta-analyzed effect estimates by imputing missing ICCs from a posterior predictive distribution constructed from a database of relevant ICCs. Read More

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"Examining the incremental and interactive effects of boldness with meanness and disinhibition within the triarchic model of psychopathy": Correction.

Personal Disord 2021 Jun 24. Epub 2021 Jun 24.

Department of Psychology, Simon Fraser University.

Reports an error in "Examining the incremental and interactive effects of boldness with meanness and disinhibition within the triarchic model of psychopathy" by Dylan T. Gatner, Kevin S. Douglas and Stephen D. Read More

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Polymerization and isomerization cyclic amplification for nucleic acid detection with attomolar sensitivity.

Chem Sci 2021 Feb 17;12(12):4509-4518. Epub 2021 Feb 17.

College of Biology, State Key Laboratory of Chemo/Biosensing and Chemometrics, College of Chemistry and Chemical Engineering, Hunan University Changsha 410082 P. R. China

DNA amplification is one of the most valuable tools for the clinical diagnosis of nucleic acid-related diseases, but current techniques for DNA amplification are based on intermolecular polymerization reactions, resulting in the risk of errors in the intermolecular reaction pattern. In this article, we introduce the concept of intramolecular polymerization and isomerization cyclic amplification (PICA), which extends a short DNA strand to a long strand containing periodic repeats of a sequence through cyclic alternating polymerization and isomerization. To the best of our knowledge, this is the first time that a real ssDNA self-extension method without any additional auxiliary oligonucleotides has been reported. Read More

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February 2021

Comparison of different approaches to quantify substituted polycyclic aromatic compounds.

J Chromatogr A 2021 Aug 3;1651:462317. Epub 2021 Jun 3.

Centre for Oil and Gas Research and Development (COGRaD), University of Manitoba, Department of Chemistry, Winnipeg, MB R3T 2N2, Canada.

Unlike native polycyclic aromatic hydrocarbons (PAHs), quantitation of substituted polycyclic aromatic compounds (PACs) has been a challenge in the environmental industry. The challenge can be attributed in part to the large number of theoretically possible isomers and the lack of authentic standards for quantitation. In addition, the lack of a unified approach to the quantitation of these compounds has led to poor interlaboratory accuracy. Read More

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Reducing the Impact of External Vibrations on Fiducial Point Detection in Seismocardiogram Signals.

IEEE Trans Biomed Eng 2021 Jun 23;PP. Epub 2021 Jun 23.

Objective: Wearable systems that enable continuous non-invasive monitoring of hemodynamic parameters can aid in cardiac health evaluation in non-hospital settings. The seismocardiogram (SCG) is a non-invasively acquired cardiovascular biosignal for which timings of fiducial points, like aortic valve opening (AO) and aortic valve closing (AC), can enable estimation of key hemodynamic parameters. However, SCG is susceptible to motion artifacts, making accurate estimation of these points difficult when corrupted by high-g or in-band vibration artifacts. Read More

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Autopsy and pre-mortem diagnostic discrepancy review in an Irish tertiary PICU.

Eur J Pediatr 2021 Jun 17. Epub 2021 Jun 17.

Department of Anesthesia and Critical Care, Children's Health Ireland at Crumlin, Dublin, Ireland.

Our study had two objectives: (1) to review ante- and post-mortem diagnoses and assign a Goldman error classification and (2) establish autopsy rates within our centre. We performed a retrospective analysis of autopsies performed on patients who died in our paediatric intensive care unit (PICU) between November 13, 2012, and October 31, 2018. Medical and autopsy data of all patients was reviewed, and Goldman classification of discrepancy between ante- and post-mortem diagnoses was assigned. Read More

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Deep-learning models for the detection and incidence prediction of chronic kidney disease and type 2 diabetes from retinal fundus images.

Nat Biomed Eng 2021 Jun 15;5(6):533-545. Epub 2021 Jun 15.

Peking University Third Affiliated Hospital, Beijing, China.

Regular screening for the early detection of common chronic diseases might benefit from the use of deep-learning approaches, particularly in resource-poor or remote settings. Here we show that deep-learning models can be used to identify chronic kidney disease and type 2 diabetes solely from fundus images or in combination with clinical metadata (age, sex, height, weight, body-mass index and blood pressure) with areas under the receiver operating characteristic curve of 0.85-0. Read More

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A 1-km hourly air-temperature model for 13 northeastern U.S. states using remotely sensed and ground-based measurements.

Environ Res 2021 Jun 12;200:111477. Epub 2021 Jun 12.

Department of Environmental Medicine and Public Health, Icahn School of Medicine at Mount Sinai, New York, NY, USA; Institute for Exposomic Research, Icahn School of Medicine at Mount Sinai, New York, USA.

Background: Accurate and precise estimates of ambient air temperatures that can capture fine-scale within-day variability are necessary for studies of air temperature and health.

Method: We developed statistical models to predict temperature at each hour in each cell of a 927-m square grid across the Northeast and Mid-Atlantic United States from 2003 to 2019, across ~4000 meteorological stations from the Integrated Mesonet, using inputs such as elevation, an inverse-distance-weighted interpolation of temperature, and satellite-based vegetation and land surface temperature. We used a rigorous spatial cross-validation scheme and spatially weighted the errors to estimate how well model predictions would generalize to new cell-days. Read More

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Development of a fluoroscopically guided robotic assistant for instrument placement in pelvic trauma surgery.

J Med Imaging (Bellingham) 2021 May 9;8(3):035001. Epub 2021 Jun 9.

Johns Hopkins University, Department of Biomedical Engineering, Baltimore, Maryland, United States.

A method for fluoroscopic guidance of a robotic assistant is presented for instrument placement in pelvic trauma surgery. The solution uses fluoroscopic images acquired in standard clinical workflow and helps avoid repeat fluoroscopy commonly performed during implant guidance. Images acquired from a mobile C-arm are used to perform 3D-2D registration of both the patient (via patient CT) and the robot (via CAD model of a surgical instrument attached to its end effector, e. Read More

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An Optical Coherence Tomography-Based Deep Learning Algorithm for Visual Acuity Prediction of Highly Myopic Eyes After Cataract Surgery.

Front Cell Dev Biol 2021 26;9:652848. Epub 2021 May 26.

Department of Ophthalmology, Eye and ENT Hospital, Eye Institute, Fudan University, Shanghai, China.

Background: Due to complicated and variable fundus status of highly myopic eyes, their visual benefit from cataract surgery remains hard to be determined preoperatively. We therefore aimed to develop an optical coherence tomography (OCT)-based deep learning algorithms to predict the postoperative visual acuity of highly myopic eyes after cataract surgery.

Materials And Methods: The internal dataset consisted of 1,415 highly myopic eyes having cataract surgeries in our hospital. Read More

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Analysis of External Quality Assessment of Maternal Serum Prenatal Screening for Down Syndrome in the First Trimester in China.

Clin Lab 2021 Jun;67(6)

Background: We analyzed the 2019 external quality assessment (EQA) results to evaluate the analytical performance of maternal serum prenatal screening for Down Syndrome (DS) in the first trimester in China.

Methods: In each round, five lyophilized EQA samples with detailed clinical information were distributed to participants and used to test the concentration of human chorionic gonadotropin free beta subunits (free β-HCG) and pregnancy-associated plasma protein-A (PAPP-A) to calculate the risk value of DS. The robust coefficient of variability (CV) was calculated or test results for free β-HCG and PAPP-A using analytes and major measurement platforms. Read More

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