726 research outputs found

    Optical quenching and recovery of photoconductivity in single-crystal diamond

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    We study the photocurrent induced by pulsed-light illumination (pulse duration is several nanoseconds) of single-crystal diamond containing nitrogen impurities. Application of additional continuous-wave light of the same wavelength quenches pulsed photocurrent. Characterization of the optically quenched photocurrent and its recovery is important for the development of diamond based electronics and sensing

    The comparison between two methods of basic life support instruction: Video self-instruction versus traditional method

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    Introduction: Medical education is changing and evolving. Teachers need to re-evaluate their medical teaching practice to enhance student learning. The data about the ideal training method of Basic Life Support (BLS) is lacking. The goal of this study was to analyse the use and performance of video self-instruction (VSI) method in BLS, in order to develop an efficient BLS training method. Methods: Eighty-one undergraduate medical interns were enrolled in a prospective clinical study in 2011. They were divided into VSI group and traditional group. We provided the first group with a DVD containing a 20-minute training video while the second group took part in a 4-hour training class of BLS. Subjects participated in a pre-test and post-test based on 2010 American Heart Association Resuscitation guideline. Results: The average scores of VSI group and the traditional group before training were 8.85±2.42 and 8.57±2.22 respectively (p=0.592). After training, the average scores of the VSI and the traditional group were 20.24±0.83 and 18.05±1.86 respectively. VSI group achieved slightly better scores compared with the traditional group (p<0.001). Conclusions: Training through VSI achieves more satisfying results than the traditional lecture method. VSI method can be considered a useful technique in undergraduate educational programs. Developing VSI can increase significantly the access to the BLS training. © 2015, Medcom Limited. All rights reserved

    Temperature measurement on neurological pulse generators during MR scans

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    According to manufacturers of both magnetic resonance imaging (MRI) machines, and implantable neurological pulse generators (IPGs), MRI is contraindicated for patients with IPGs. A major argument for this restriction is the risk to induce heat in the leads due to the electromagnetic field, which could be dangerous for the surrounding brain parenchyma. The temperature change on the surface of the case of an ITREL-III (Medtronic Inc., Minneapolis, MN) and the lead tip during MRI was determined. An anatomical realistic and a cubic phantom, filled with phantom material mimicking human tissue, and a typical lead configuration were used to imitate a patient who carries an IPG for deep brain stimulation. The measurements were performed in a 1.5 T and a 3.0 T MRI. 2.1°C temperature increases at the lead tip uncovered the lead tip as the most critical part concerning heating problems in IPGs. Temperature increases in other locations were low compared to the one at the lead tip. The measured temperature increase of 2.1°C can not be considered as harmful to the patient. Comparison with the results of other studies revealed the avoidance of loops as a practical method to reduce heating during MRI procedures

    Il10 Deficiency Rebalances Innate Immunity to Mitigate Alzheimer-Like Pathology

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    SummaryThe impact of inflammation suppressor pathways on Alzheimer’s disease (AD) evolution remains poorly understood. Human genetic evidence suggests involvement of the cardinal anti-inflammatory cytokine, interleukin-10 (IL10). We crossed the APP/PS1 mouse model of cerebral amyloidosis with a mouse deficient in Il10 (APP/PS1+Il10−/−). Quantitative in silico 3D modeling revealed activated Aβ phagocytic microglia in APP/PS1+Il10−/− mice that restricted cerebral amyloidosis. Genome-wide RNA sequencing of APP/PS1+Il10−/− brains showed selective modulation of innate immune genes that drive neuroinflammation. Il10 deficiency preserved synaptic integrity and mitigated cognitive disturbance in APP/PS1 mice. In vitro knockdown of microglial Il10-Stat3 signaling endorsed Aβ phagocytosis, while exogenous IL-10 had the converse effect. Il10 deficiency also partially overcame inhibition of microglial Aβ uptake by human Apolipoprotein E. Finally, the IL-10 signaling pathway was abnormally elevated in AD patient brains. Our results suggest that “rebalancing” innate immunity by blocking the IL-10 anti-inflammatory response may be therapeutically relevant for AD

    Free-breathing Pulmonary (1)H and Hyperpolarized (3)He MRI: Comparison in COPD and Bronchiectasis.

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    RATIONALE AND OBJECTIVES: In this proof-of-concept demonstration, we aimed to quantitatively and qualitatively compare pulmonary ventilation abnormalities derived from Fourier decomposition of free-breathing (1)H magnetic resonance imaging (FDMRI) to hyperpolarized (3)He MRI in subjects with chronic obstructive pulmonary disease (COPD) and bronchiectasis. MATERIALS AND METHODS: All subjects provided written informed consent to a protocol approved by a local research ethics board and Health, Canada, and they underwent MRI, computed tomography (CT), spirometry, and plethysmography during a single 2-hour visit. Semiautomated segmentation was used to generate ventilation defect measurements derived from FDMRI and (3)He MRI, and these were compared using analysis of variance and Pearson correlations. RESULTS: Twenty-six subjects were evaluated including 12 COPD subjects (67 ± 9 years) and 14 bronchiectasis subjects (70 ± 11 years). For COPD subjects, FDMRI and (3)He MRI ventilation defect percent (VDP) was 7 ± 6% and 24 ± 14%, respectively (P \u3c .001; bias = -16 ± 9%). In COPD subjects, FDMRI was significantly correlated with (3)He MRI VDP (r = .88; P = .0001), (3)He MRI apparent diffusion coefficient (r = .71; P \u3c .05), airways resistance (r = .60; P \u3c .05), and RA950 (r = .80; P \u3c .01). In subjects with bronchiectasis, FDMRI VDP (5 ± 3%) and (3)He MRI VDP (18 ± 9%) were significantly different (P \u3c .001) and not correlated (P \u3e .05). The Dice similarity coefficient (DSC) for FDMRI and (3)He MRI ventilation was 86 ± 7% for COPD and 86 ± 4% for bronchiectasis subjects (P \u3e .05); the DSC for FDMRI ventilation defects and CT RA950 was 19 ± 20% in COPD and 2 ± 3% in bronchiectasis subjects (P \u3c .01). CONCLUSIONS: FDMRI and (3)He MRI VDP were strongly related in COPD but not in bronchiectasis subjects. In COPD only, FDMRI ventilation defects were spatially related with (3)He ventilation defects and emphysema

    Societal issues concerning the application of artificial intelligence in medicine

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    Medicine is becoming an increasingly data-centred discipline and, beyond classical statistical approaches, artificial intelligence (AI) and, in particular, machine learning (ML) are attracting much interest for the analysis of medical data. It has been argued that AI is experiencing a fast process of commodification. This characterization correctly reflects the current process of industrialization of AI and its reach into society. Therefore, societal issues related to the use of AI and ML should not be ignored any longer and certainly not in the medical domain. These societal issues may take many forms, but they all entail the design of models from a human-centred perspective, incorporating human-relevant requirements and constraints. In this brief paper, we discuss a number of specific issues affecting the use of AI and ML in medicine, such as fairness, privacy and anonymity, explainability and interpretability, but also some broader societal issues, such as ethics and legislation. We reckon that all of these are relevant aspects to consider in order to achieve the objective of fostering acceptance of AI- and ML-based technologies, as well as to comply with an evolving legislation concerning the impact of digital technologies on ethically and privacy sensitive matters. Our specific goal here is to reflect on how all these topics affect medical applications of AI and ML. This paper includes some of the contents of the “2nd Meeting of Science and Dialysis: Artificial Intelligence,” organized in the Bellvitge University Hospital, Barcelona, Spain.Peer ReviewedPostprint (author's final draft

    Can intravenous acetaminophen reduce the needs to more opioids to control pain in intubated patients?

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    Aims: To evaluate the effect of intravenous (IV) acetaminophen on reducing the need for morphine sulfate in intubated patients admitted to the Intensive Care Unit (ICU). Settings and Design: Current study was done as a clinical trial on the patients supported by mechanical ventilator. Subjects and Methods: Behavioral pain scale (BPS) scoring system was used to measure pain in the patients. All of the patients received 1 g, IV acetaminophen, every 6 h during the 1 st and 3 rd days of admission and placebo during the 2 nd and 4 th days. Total dose of morphine sulfate needed, its complications, and the BPS scores at the end of every 6 h interval were compared. Results: Totally forty patients were enrolled. The mean pain scores were significantly lower in the 2 nd and 4 th days (4.33 and 3.66, respectively; mean: 4.0) in which the patients had received just morphine sulfate compared to the 1 st and 3 rd days (7.36 and 3.93, respectively; mean: 5.65) in which the patients had received acetaminophen in addition to morphine sulfate too (P &lt; 0.001). Cumulative dose of morphine sulfate used, was significantly higher in the 1 st and 3 rd days (8.92 and 3.15 mg, respectively; 12.07 mg in total) compared to the 2 nd and 4 th days (6.47 mg and 3.22 mg, respectively; 9.7 mg in total) (P = 0.035). Conclusion: In our study, IV acetaminophen had no effect on decreasing the BPSs and need of morphine sulfate in intubated patients admitted to ICU. © 2016 Indian Journal of Critical Care Medicine

    Structural Attributes and Photodynamics of Visible Spectrum Quantum Emitters in Hexagonal Boron Nitride

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    Newly discovered van der Waals materials like MoS2, WSe2, hexagonal boron nitride (h-BN), and recently C2N have sparked intensive research to unveil the quantum behavior associated with their 2D structure. Of great interest are 2D materials that host single quantum emitters. h-BN, with a band gap of 5.95 eV, has been shown to host single quantum emitters which are stable at room temperature in the UV and visible spectral range. In this paper we investigate correlations between h-BN structural features and emitter location from bulk down to the monolayer at room temperature. We demonstrate that chemical etching and ion irradiation can generate emitters in h-BN. We analyze the emitters' spectral features and show that they are dominated by the interaction of their electronic transition with a single Raman active mode of h-BN. Photodynamics analysis reveals diverse rates between the electronic states of the emitter. The emitters show excellent photo stability even under ambient conditions and in monolayers. Comparing the excitation polarization between different emitters unveils a connection between defect orientation and the h-BN hexagonal structure. The sharp spectral features, color diversity, room-temperature stability, long-lived metastable states, ease of fabrication, proximity of the emitters to the environment, outstanding chemical stability, and biocompatibility of h-BN provide a completely new class of systems that can be used for sensing and quantum photonics applications

    Electrocardiographic changes in patients with tramadol-induced idiosyncratic seizures

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    Objectives To assess ECG changes in patients with tramadol-induced seizure(s) and compare these changes in lower and higher than 500 mg tramadol doses as a main goal. Material and methods In an analytical-cross sectional manner over 1 year, 170 patients with idiosyncratic seizure(s) after using tramadol, were studied. Full data were recorded for each patient. ECGs were taken from all the patients on admission and 1 h later and were assessed for findings. Results 70 of 170 patients (41.2) had used lower than 500 mg doses of tramadol while 90 patients (52.9) were included in the high dose group. Rate of female patients in the high dose group was significantly higher. The average age of patients in the high dose group was significantly lower (22.04 vs 25.76). The high dose group had significantly higher heart rates. There was no history of cardiovascular diseases; two patients had previous history of seizure. No significant difference was shown between low dose and high dose groups from the point of ECG changes. Discussion and conclusion Using doses higher than 500 mg is more frequently seen in women, young people and those who have not experienced previous use of tramadol. Terminal S wave, sinus tachycardia, and terminal R wave in the lead aVR are among the most common ECG changes in tramadol users. © 2016 The Emergency Medicine Association of Turke
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