Accelerated cardiac T1 mapping in four heartbeats with inline MyoMapNet: a deep learning-based T1 estimation approach

Purpose To develop and evaluate MyoMapNet, a rapid myocardial T1 mapping approach that uses fully connected neural networks (FCNN) to estimate T1 values from four T1-weighted images collected after a single inversion pulse in four heartbeats (Look-Locker, LL4). Method We implemented an FCNN for MyoMapNet to estimate T1 values from a reduced number of T1-weighted images and corresponding inversion-recovery times. We studied MyoMapNet performance when trained using native, post-contrast T1, or a combination of both. We also explored the effects of number of T1-weighted images (four and five) for native T1. After rigorous training using in-vivo modified Look-Locker inversion recovery (MOLLI) T1 mapping data of 607 patients, MyoMapNet performance was evaluated using MOLLI T1 data from 61 patients by discarding the additional T1-weighted images. Subsequently, we implemented a prototype MyoMapNet and LL4 on a 3 T scanner. LL4 was used to collect T1 mapping data in 27 subjects with inline T1 map reconstruction by MyoMapNet. The resulting T1 values were compared to MOLLI. Results MyoMapNet trained using a combination of native and post-contrast T1-weighted images had excellent native and post-contrast T1 accuracy compared to MOLLI. The FCNN model using four T1-weighted images yields similar performance compared to five T1-weighted images, suggesting that four T1 weighted images may be sufficient. The inline implementation of LL4 and MyoMapNet enables successful acquisition and reconstruction of T1 maps on the scanner. Native and post-contrast myocardium T1 by MOLLI and MyoMapNet was 1170 ± 55 ms vs. 1183 ± 57 ms (P = 0.03), and 645 ± 26 ms vs. 630 ± 30 ms (P = 0.60), and native and post-contrast blood T1 was 1820 ± 29 ms vs. 1854 ± 34 ms (P = 0.14), and 508 ± 9 ms vs. 514 ± 15 ms (P = 0.02), respectively. Conclusion A FCNN, trained using MOLLI data, can estimate T1 values from only four T1-weighted images. MyoMapNet enables myocardial T1 mapping in four heartbeats with similar accuracy as MOLLI with inline map reconstruction.

Cancer Research in the Time of COVID-19: A Colombian Narrative

Cancer research is deficient in Colombia and efforts and resources diverted due to the COVID-19 pandemic could worsen the situation. We explore the impact of the pandemic on cancer research funding, output, and conduct. We sought information at national level and used the experience of an academic reference center to contrast the impact at institutional level. We searched databases and official documents of national governmental institutions, trial registries, hospital registries, and the Web of Science. We interviewed principal investigators (PIs) to retrieve information on the conduct of cancer research. A decline in resource availability and new proposals was observed at the national level with a shift to COVID-19 related research. However, at institutional level there was no decline in the number of cancer research proposals. The predominance of observational studies as opposed to the preponderance of clinical trials and basic science in high-income countries may be related to the lower impact at institutional level. Nevertheless, we found difficulties similar to previous reports for conducting research during the pandemic. PIs reported long recovery times and a great impact on research other than clinical trials, such as observational and qualitative studies. No significant impact on research output was observed. Alternatives to ensure research continuity such as telemedicine and remote data collection have scarcely been implemented given limited access and low technology literacy. In this middle-income setting the situation shows a notable dependency of international collaborations to develop research on COVID-19 and cancer and to overcome challenges for cancer research during the pandemic.

Effect of Working Atmospheres on the Detection of Diacetyl by Resistive SnO2 Sensor

Nanostructured metal oxide semiconductors (MOS) are considered proper candidates to develop low cost and real-time resistive sensors able to detect volatile organic compounds (VOCs), e.g., diacetyl. Small quantities of diacetyl are generally produced during the fermentation and storage of many foods and beverages, conferring a typically butter-like aroma. Since high diacetyl concentrations are undesired, its monitoring is fundamental to identify and characterize the quality of products. In this work, a tin oxide sensor (SnO2) is used to detect gaseous diacetyl. The effect of different working atmospheres (air, N2 and CO2), as well as the contemporary presence of ethanol vapors, used to reproduce the typical alcoholic fermentation environment, are evaluated. SnO2 sensor is able to detect diacetyl in all the analyzed conditions, even when an anaerobic environment is considered, showing a detection limit lower than 0.01 mg/L and response/recovery times constantly less than 50 s.

Adverse Event Profile for Nanoparticle Albumin-Bound Paclitaxel Compared With Solvent-Based Taxanes in Solid-Organ Tumors: A Systematic Review and Meta-Analysis of Randomized Clinical Trials

Background: Nanoparticle albumin-bound paclitaxel (nab-paclitaxel) is an innovative form of taxane that has superior antitumor effects; however, the safety profile between nab-paclitaxel and traditional taxanes remains controversial. Objective: To determine the burden of adverse events (AEs) in patients with multiple malignancies receiving nab-paclitaxel compared with that in patients receiving traditional taxanes. Methods: Randomized clinical trials comparing nab-paclitaxel with traditional taxanes (solvent-based paclitaxel [sb-paclitaxel] or docetaxel) in the treatment of primary solid-organ malignancies were included if AEs were reported as an outcome. Statistical analyses were conducted to calculate the summary odds ratio (OR) of the relevant adverse outcomes related to nab-paclitaxel and traditional taxanes. Prespecified subgroup analyses based on intervention and doses, primary tumor sites, and different ethnic groups were also performed. Results: Twelve clinical trials were included in the meta-analysis. Grade 3/4 anemia, thrombocytopenia, and neurotoxicity were more frequent with nab-paclitaxel than with traditional taxanes. Nab-paclitaxel at 100 or 125 mg/m2/w dosage was associated with fewer or similar grade 3/4 specific AEs. Allergy was less common with nab-paclitaxel. The median recovery times of neurotoxicity were 25, 64, and 37 days in patients receiving nab-paclitaxel, sb-paclitaxel, and docetaxel, respectively. Elevated incidences of specific AEs were more common in breast cancer and non-Asian patients than in other malignancies and ethnic groups, respectively. Conclusion and Relevance: Nab-paclitaxel increased the risk of hematologic and non-hematologic AEs in general, but anaphylaxis was less common, and the recovery duration of neurotoxicity was shorter. Weekly administration of nab-paclitaxel at a lower dosage provided better tolerance.

Flexible Ni/NiOx-Based Sensor for Human Breath Detection

We developed a simple methodology to fabricate an Ni/NiOx-based flexible breath sensor by a single-step laser digital patterning process of solution-processed NiOx thin-film deposited using NiOx nanoparticle ink. Laser-induced reductive sintering phenomenon enables for the generation of three parts of Ni electrodes and two narrow NiOx-sensing channels in between, defined on a single layer on a thin flexible polymer substrate. The Ni/NiOx-based breath sensor efficiently detects human breath at a relatively low operating temperature (50 °C) with fast response/recovery times (1.4 s/1.7 s) and excellent repeatability. The mechanism of the gas-sensing ability enhancement of the sensor was investigated by X-ray photoelectron spectroscopy analysis. Furthermore, by decoupling of the temperature effect from the breathing gas, the response of the sensor due to the temperature alone and due to the chemical components in the breathing gas could be separately evaluated. Finally, bending and cyclic bending tests (10,000 cycles) demonstrated the superior mechanical stability of the flexible breath sensor.

ADHD and DIRAS Single Nucleotide Polymorphism as an Indicator of Prolonged Concussion Recovery

The purpose of this study was to determine the association between the presence of a single nucleotide polymorphism (SNP; rs1412005) within DIRAS2 (i.e., a gene associated with attention-deficit/hyperactivity disorder (ADHD) and prolonged recovery following a sport-related concussion. A case-control study design was implemented, where cases and controls were selected from a cohort of 117 deidentified concussed athletes. Eleven samples from this patient cohort self-reported ADHD diagnosis and were age and sex-matched to 22 participants with no self-reported ADHD diagnoses. The average recovery times were 21.50 + 13.96 days and 15.66 + 8.50 days for the case and control groups, respectively. The authors found that only 13.6% of the individuals without an ADHD diagnosis recovered in > 30 days (p = 0.044). Also, the authors found that 72.7% of the carriers of the T allele (i.e., minor allele) recovered in greater than 30 days (p = 0.213). Researchers concluded that individuals with ADHD had a higher risk of prolonged concussion recovery lasting greater than 30 days. Also, carrying the rare allele was associated with prolonged recovery, which suggests this SNP could be a potential genetic marker for both prolonged concussion recovery and the presence of ADHD.

Synthesis, Characterization, and Hydrogen Gas Sensing of ZnO/g-C3N4 Nanocomposite

In this paper, the preparation of the ZnO/g-C3N4 nanocomposite is discussed. The synthesis of nanocomposite is performed by the direct pyrolysis of the precursor (zinc acetate hexahydrate). The material synthesis is validated by different characterization tools, such as X-ray Diffraction (XRD), Scanning electron microscopy (SEM), Transmission electron microscopy (TEM). The SEM and TEM analysis revealed the formation of nanorods on g-C3N4 support. The gas sensing property of the ZnO/g-C3N4 was studied for various concentrations of hydrogen gas. Response and recovery times were recorded by the sensor.

Evaluating the Landslide Stability and Vegetation Recovery: Case Studies in the Tsengwen Reservoir Watershed in Taiwan

The sediment yield from numerous landslides triggered in Taiwan’s mountainous regions by 2009 Typhoon Morakot have had substantial long-term impacts on the evolution of rivers. This study evaluated the long-term evolution of landslides induced by 2001 Typhoon Nari and 2009 Typhoon Morakot in the Tsengwen Reservoir Watershed by using multiannual landslide inventories and rainfall records for the 2001–2017 period. The landslide activity, vegetation recovery time, and the landslide spatiotemporal hotspot analyses were used in the study. Severe landslides most commonly occurred on 35–45° slopes at elevations of 1400–2000 m located within 500 m of the rivers. The average vegetation recovery time was 2.29 years, and landslides with vegetation recovery times exceeding 10 years were most frequently retrogressive landslide, riverbank landslides in sinuous reaches, and the core area of large landslides. The annual landslide area decline ratios after 2009 Typhoon Morakot in Southern Taiwan was 4.75% to 7.45%, and the time of landslide recovery in the Tsengwen reservoir watershed was predicted to be 28.48 years. Oscillating hotspots and coldspots occupied 95.8% of spatiotemporal patterns in the watershed area. The results indicate that landslides moved from hillslopes to rivers in the 2001–2017 period because the enormous amount of sediment deposited in rivers resulted in the change of river geomorphology and the riverbank landslides.

Silicon MEMS Thermocatalytic Gas Sensor in Miniature Surface Mounted Device Form

A reduced size thermocatalytic gas sensor was developed for the detection of methane over the 20% of the explosive concentration. The sensor chip is formed from two membranes with a 150 µm diameter heated area in their centers and covered with highly dispersed nano-sized catalyst and inert reference, respectively. The power dissipation of the chip is well below 70 mW at the 530 °C maximum operation temperature. The chip is mounted in a novel surface mounted metal-ceramic sensor package in the form-factor of SOT-89. The sensitivity of the device is 10 mV/v%, whereas the response and recovery times without the additional carbon filter over the chip are <500 ms and <2 s, respectively. The tests have shown the reliability of the new design concerning the hotplate stability and massive encapsulation, but the high degradation rate of the catalyst coupled with its modest chemical power limits the use of the sensor only in pulsed mode of operation. The optimized pulsed mode reduces the average power consumption below 2 mW.

Use of intravenous lidocaine for dose reduction of propofol in paediatric colonoscopy patients: a randomised placebo-controlled study

Background Propofol, a widely used sedative in endoscopic procedures, sometimes causes cardiopulmonary complications. Intravenous lidocaine can diminish visceral pain and decrease the dose of propofol. The purpose of this study was to assess the efficacy and safety of intravenous lidocaine in reducing propofol dosage during paediatric colonoscopy. Methods Forty children who underwent colonoscopy were divided into two groups. Lidocaine hydrochloride (1.5 mg/kg induction and 2 mg/kg/h maintenance) was given intravenously to the lidocaine group, and the same amount of saline was given to the control group after they received lidocaine induction. Propofol initial plasma concentration of 5 μg/mL was targeted, and the procedure was performed after the bispectral index value reached 55. The primary outcome was propofol requirement. Results The propofol requirement in the lidocaine group was decreased by 35.5% (128.6 ± 30.4 mg vs. 199.4 ± 57.6 mg; p < 0.001; 95%CI: − 100.60, − 41.02). The incidence of involuntary body movements was significantly lower in the lidocaine group (p = 0.028; OR = 0.17; 95%CI: 0.03, 0.92). The awakening time (p < 0.001; 95%CI: − 7.67, − 5.13) and recovery times (p < 0.001; 95%CI: − 7.45, − 4.35) were significantly lower in the lidocaine group. Pain was significantly less at 30 min and 60 min after the procedure in the lidocaine group (0 [0–4] vs. 3 [0–5], p < 0. 001; 0 [0–2] vs. 1 [0–3], p = 0.001). There was no difference in the incidence of bradycardia, hypotension, or hypoxia between the two groups. Conclusions For colonoscopy procedures in paediatric patients, intravenous lidocaine reduces the amount of propofol needed, provides better sedation and postprocedural pain management, as well as a reduction in recovery time. Trial registration The trial was registered on November 6, 2020 at China Clinical Trials Registration Center (www.chictr.org.cn) ref.: ChiCTR 2,000,039,706.