Dust detection by antenna instruments

2020 ◽  
Author(s):  
Zoltan Sternovsky ◽  
Ming-Hsueh Shen ◽  
Michael DeLuca ◽  
Åshild Fredriksen ◽  
Mihály Horányi ◽  
...  
Keyword(s):  
Sampling Rate ◽  
Laboratory Data ◽  
Quantitative Description ◽  
High Rate ◽  
Dust Particles ◽  
Electric Signal ◽  
Accelerator Facility ◽  
Spacecraft Potential ◽  
Dust Detection ◽  
The Impact

<p>Antenna instruments on space missions have been used to detect dust particles and characterize dust populations. The antennas register the transient electric signal generated by the expansion of the impact plasma from the dust impact on the spacecraft body or the antenna. Given the large effective sensitive area, antenna instruments offer an advantage over dedicated dust detectors for dust populations with low fluxes. The dust accelerator facility operated at the University of Colorado has been employed to investigate the physical mechanisms of antenna signal generation. The dominant mechanism is related to the charging of the spacecraft (or antenna) by collecting some fraction of electrons and ions from the impact plasma. We have carried out a number of experimental campaigns in order to characterize the dust impact charge yields from relevant materials, the effective temperatures of dust impact plasmas, and variations of the antenna signals with spacecraft potential, or magnetic field. Here we report on a physical model that provides a good qualitative and quantitative description of the antenna waveforms recorded in laboratory conditions. The model is based on the separation of the electrons from the ions in the impact plasma and their different timescales of expansion. The escaping and collected fractions of charges are driven by the spacecraft potential. Fitting the model to the laboratory data revealed that the electrons in the impact plasma have an isotropic distribution, while ions are dominantly moving away from the dust impact location. Identifying the fine details in the antenna signals requires a relatively high sampling rate and thus not commonly resolved for past instruments. The high-rate mode of the FIELDS instrument on the Parker Solar Probe, however, can be used to verify the proposed model.</p>

Dust impact detections by a set of Faraday cups in the lunar environments

2020 ◽  
Author(s):  
Oleksii Kononov ◽  
Jiří Pavlů ◽  
Libor Nouzák ◽  
Jana Šafránková ◽  
Zdeněk Němeček ◽  
...  
Keyword(s):  
Solar Wind ◽  
Sampling Rate ◽  
Identification Algorithm ◽  
Impact Pulse ◽  
Ion Energy ◽  
Ion Energy Distribution ◽  
Hypervelocity Impacts ◽  
Dust Detection ◽  
The Impact ◽  
Novel Design

<p>The Bright Monitor of the Solar Wind (BMSW) for the Luna-Resurs-1 mission is an instrument designed for high-time (30 ms) resolution measurements of moments of the ion energy distribution by Faraday cups in the solar wind and in a plasma environment at altitudes between 65 and 150 km above the lunar surface. Previous studies performed by a similar instrument located on-board the Spektr-R spacecraft demonstrated a possibility to detect hypervelocity impacts of dust grains by such instruments Our analysis shows that the main problem of the reliable detection of dust impacts using such types of instruments is their sampling rate. In the paper, we present a novel design of a set of FCs that improves the ability of the dust detection using a simple identification algorithm that can store data with a higher sampling rate around the impact pulse. Moreover, we discuss a calibration of the detectors and their front-end electronics using the dust accelerator in order to find a relation between impact parameters and pulse heights.</p>

Glucose Levels and Outcome After Primary Intraventricular Hemorrhage

2019 ◽  
Vol 16 (1) ◽  
pp. 40-46
Author(s):  
Rui Guo ◽  
Ruiqi Chen ◽  
Chao You ◽  
Lu Ma ◽  
Hao Li ◽  
...  
Keyword(s):  
Diabetes Mellitus ◽  
Blood Glucose ◽  
Blood Glucose Level ◽  
Incidence Rate ◽  
Glucose Level ◽  
Intraventricular Hemorrhage ◽  
Laboratory Data ◽  
History Of ◽  
Poor Outcomes ◽  
The Impact

Background and Purpose: Hyperglycemia is reported to be associated with poor outcome in patients with spontaneous Intracerebral Hemorrhage (ICH), but the association between blood glucose level and outcomes in Primary Intraventricular Hemorrhage (PIVH) remains unclear. We sought to identify the parameters associated with admission hyperglycemia and analyze the impact of hyperglycemia on clinical outcome in patients with PIVH. Methods: Patients admitted to Department of Neurosurgery, West China Hospital with PIVH between 2010 and 2016 were retrospectively included in our study. Clinical, radiographic, and laboratory data were collected. Univariate and multivariate logistic regression analyses were used to identify independent predictors of poor outcomes. Results: One hundred and seventy patients were included in the analysis. Mean admission blood glucose level was 7.78±2.73 mmol/L and 10 patients (5.9%) had a history of diabetes mellitus. History of diabetes mellitus (P = 0.01; Odds Ratio [OR], 9.10; 95% Confidence Interval [CI], 1.64 to 50.54) was independent predictor of admission critical hyperglycemia defined at 8.17 mmol/L. Patients with admission critical hyperglycemia poorer outcome at discharge (P < 0.001) and 90 days (P < 0.001). After adjustment, admission blood glucose was significantly associated with discharge (P = 0.01; OR, 1.30; 95% CI, 1.06 to 1.59) and 90-day poor outcomes (P = 0.03; OR, 1.27; 95% CI, 1.03 to 1.58), as well as mortality at 90 days (P = 0.005; OR, 1.41; 95% CI, 1.11 to 1.78). In addition, admission critical hyperglycemia showed significantly increased the incidence rate of pneumonia in PIVH (P = 0.02; OR, 6.04; 95% CI 1.27 to 28.80) even after adjusting for the confounders. Conclusion: Admission blood glucose after PIVH is associated with discharge and 90-day poor outcomes, as well as mortality at 90 days. Admission hyperglycemia significantly increases the incidence rate of pneumonia in PIVH.

Others' participation rate influences an individual's charitable behavior: Others' similarity as a moderator

2017 ◽  
Vol 45 (10) ◽  
pp. 1607-1618 ◽  
Author(s):  
Seung Yun Lee ◽  
Sunho Jung ◽  
Sangdo Oh ◽  
Seong Hoon Park
Keyword(s):  
Undergraduate Students ◽  
Participation Rate ◽  
High Rate ◽  
Charitable Behavior ◽  
High Participation ◽  
Negative Effect ◽  
The Impact ◽  
And Diffusion ◽  
High Participation Rate ◽  
Diffusion Of Responsibility

We proposed that a moderator, others' similarity, would determine the impact of high participation rates of others on an individual's charitable behavior, and aimed to show that this moderator would work through the diffusion of responsibility motive. Participants (N = 152 undergraduate students) completed measures of charitable behavior and diffusion of responsibility, after being assigned to 1 of 2 conditions where a set percentage of other students (manipulated as either similar undergraduate students or dissimilar graduate students) were stated to have already donated to a charitable campaign (high contribution condition = 70% participation, low contribution condition = 30% participation). Our results showed that the high participation rate of others increased an individual's charitable behavior when the others in question were similar to that individual, but not when the others were dissimilar. In addition, the high rate of participation by others increased the diffusion of responsibility motive when the others in question were dissimilar to that individual, leading to a negative effect on that individual's charitable behavior.

scholarly journals The Impact of Ambient Atmospheric Mineral-Dust Particles on the Calcification of Lungs

Minerals ◽  
2021 ◽  
Vol 11 (2) ◽  
pp. 125
Author(s):  
Mariola Jabłońska ◽  
Janusz Janeczek ◽  
Beata Smieja-Król
Keyword(s):  
Mineral Dust ◽  
Smoking Habit ◽  
Lower Lobe ◽  
Ambient Air ◽  
Dust Particles ◽  
Masking Effect ◽  
Amorphous Calcium Carbonate ◽  
Calcium Salts ◽  
The Impact ◽  
First Time

For the first time, it is shown that inhaled ambient air-dust particles settled in the human lower respiratory tract induce lung calcification. Chemical and mineral compositions of pulmonary calcium precipitates in the lung right lower-lobe (RLL) tissues of 12 individuals who lived in the Upper Silesia conurbation in Poland and who had died from causes not related to a lung disorder were determined by transmission and scanning electron microscopy. Whereas calcium salts in lungs are usually reported as phosphates, calcium salts precipitated in the studied RLL tissue were almost exclusively carbonates, specifically Mg-calcite and calcite. These constituted 37% of the 1652 mineral particles examined. Mg-calcite predominated in the submicrometer size range, with a MgCO3 content up to 50 mol %. Magnesium plays a significant role in lung mineralization, a fact so far overlooked. The calcium phosphate (hydroxyapatite) content in the studied RLL tissue was negligible. The predominance of carbonates is explained by the increased CO2 fugacity in the RLL. Carbonates enveloped inhaled mineral-dust particles, including uranium-bearing oxides, quartz, aluminosilicates, and metal sulfides. Three possible pathways for the carbonates precipitation on the dust particles are postulated: (1) precipitation of amorphous calcium carbonate (ACC), followed by its transformation to calcite; (2) precipitation of Mg-ACC, followed by its transformation to Mg-calcite; (3) precipitation of Mg-free ACC, causing a localized relative enrichment in Mg ions and subsequent heterogeneous nucleation and crystal growth of Mg-calcite. The actual number of inhaled dust particles may be significantly greater than was observed because of the masking effect of the carbonate coatings. There is no simple correlation between smoking habit and lung calcification.

scholarly journals Peculiarities of Neurostimulation by Intense Nanosecond Pulsed Electric Fields: How to Avoid Firing in Peripheral Nerve Fibers

2021 ◽  
Vol 22 (13) ◽  
pp. 7051
Author(s):  
Vitalii Kim ◽  
Emily Gudvangen ◽  
Oleg Kondratiev ◽  
Luis Redondo ◽  
Shu Xiao ◽  
...  
Keyword(s):  
Side Effects ◽  
Electric Fields ◽  
Pulsed Electric Fields ◽  
Opposite Polarity ◽  
Nerve Fibers ◽  
High Rate ◽  
Excitation Threshold ◽  
Compound Action Potentials ◽  
Supramaximal Stimulation ◽  
The Impact

Intense pulsed electric fields (PEF) are a novel modality for the efficient and targeted ablation of tumors by electroporation. The major adverse side effects of PEF therapies are strong involuntary muscle contractions and pain. Nanosecond-range PEF (nsPEF) are less efficient at neurostimulation and can be employed to minimize such side effects. We quantified the impact of the electrode configuration, PEF strength (up to 20 kV/cm), repetition rate (up to 3 MHz), bi- and triphasic pulse shapes, and pulse duration (down to 10 ns) on eliciting compound action potentials (CAPs) in nerve fibers. The excitation thresholds for single unipolar but not bipolar stimuli followed the classic strength–duration dependence. The addition of the opposite polarity phase for nsPEF increased the excitation threshold, with symmetrical bipolar nsPEF being the least efficient. Stimulation by nsPEF bursts decreased the excitation threshold as a power function above a critical duty cycle of 0.1%. The threshold reduction was much weaker for symmetrical bipolar nsPEF. Supramaximal stimulation by high-rate nsPEF bursts elicited only a single CAP as long as the burst duration did not exceed the nerve refractory period. Such brief bursts of bipolar nsPEF could be the best choice to minimize neuromuscular stimulation in ablation therapies.

Intra-aortic balloon pump as a bridge therapy to heart transplant in refractory heart failure

2020 ◽  
Vol 41 (Supplement_2) ◽  
Author(s):  
G.A.B Boros ◽  
V.S.C Bellini ◽  
D Fatori ◽  
C Bernoche ◽  
M.F Macatrao-Costa ◽  
...  
Keyword(s):  
Heart Failure ◽  
Intensive Care ◽  
Heart Transplant ◽  
Insertion Site ◽  
Laboratory Data ◽  
Central Venous Oxygen Saturation ◽  
Single Center ◽  
Intra Aortic Balloon Pump ◽  
The Impact ◽  
Bridge Therapy

Abstract Background The role of intra-aortic balloon pump (IABP) in advanced heart failure (HF) treatment is still under debate. Some heart transplant (HTx) candidates on the waiting list require mechanical support, and IABP may be the simple and most available device. Purpose Describe the impact of IABP treatment in advanced HF patients who underwent HTx. Methods We retrospectively analysis patients who underwent HTx from a single center intensive care unit (ICU), between 2009 and 2018, to evaluate the use of IABP as bridge therapy. Selection included decompensated chronic HF patients that required intensive care with optimized intravenous drugs before IABP placement. Exclusion criteria were acute myocardial infarction or cardiac surgery 90 days prior to admission, and implant of ventricular assist device before HTx. Results We included 134 HF patients with IABP therapy before HTx. Insertion site was exclusively femoral. Mean time of IABP onset to HTx were 26±21 days, and hospital admission to HTx 65±45 days. The main cardiomyopathy etiology was Chagas Disease (46%) and mean LVEF was 23±6% (TABLE 1). Clinical and laboratory data were compared before and 96 hours after IABP therapy. Mean central venous oxygen saturation (SvO2) increased from 49.7±14.6% to 67.4±11.3% (p&lt;0.001), creatinine decreased from 1.77±0.9 mg/dL to 1.40±0.6 mg/dL (p&lt;0.001), and urine output increased from 1552±886 mL/24h to 2189±1029 mL/24h (p&lt;0.001). These differences were sustained or improved until the day before HTx (FIGURE 1). After 96 hours dobutamine was maintained in 98% of patients, nitroprusside increased from 56% to 67%, milrinone decreased from 26% to 20%, and norepinephrine decreased from 18% to 3%. Significant IABP complications were few (5.2%; n=7: 3 infections, 2 major bleeding, 2 arterial injury). Conclusion In this single center ICU sample, IABP improved hemodynamic status and renal function in refractory HF patients waiting for HTx. IABP can be a reasonable, available and effective bridging therapy. Figure 1 Funding Acknowledgement Type of funding source: None

scholarly journals Evaluation of Marblewood Dust’s (Marmaroxylon racemosum) Effect on Ignition Risk

2021 ◽  
Vol 11 (15) ◽  
pp. 6874
Author(s):  
Miroslava Vandličkova ◽  
Iveta Markova ◽  
Katarina Holla ◽  
Stanislava Gašpercová
Keyword(s):  
Particle Size ◽  
Dust Particles ◽  
Wood Dust ◽  
Sieve Analysis ◽  
Granulometric Analysis ◽  
Analysis Measurement ◽  
Risk Research ◽  
Minimum Ignition Temperature ◽  
The Impact

The paper deals with the selected characteristics, such as moisture, average bulk density, and fraction size, of tropical marblewood dust (Marmaroxylon racemosum) that influence its ignition risk. Research was focused on sieve analysis, granulometric analysis, measurement of moisture level in the dust, and determination of the minimum ignition temperatures of airborne tropical dust and dust layers. Samples were prepared using a Makita 9556CR 1400W grinder and K36 sandpaper for the purpose of selecting the percentages of the various fractions (<63, 63, 71, 100, 200, 315, 500 μm). The samples were sized on an automatic vibratory sieve machine Retsch AS 200. More than 65% of the particles were determined to be under 100 μm. The focus was on microfractions of tropical wood dust (particles with a diameter of ≤100 µm) and on the impact assessment of particle size (particle size <100 µm) on the minimum ignition temperatures of airborne tropical dust and dust layers. The minimum ignition temperature of airborne marblewood dust decreased with the particle size to the level of 400 °C (particle size 63 μm).

scholarly journals The High-Rate Sealed MRPC to Promote Pollutant Exchange in Gas Gaps: Status on the Development and Observations

2021 ◽  
Vol 11 (11) ◽  
pp. 4722
Author(s):  
Botan Wang ◽  
Xiaolong Chen ◽  
Yi Wang ◽  
Dong Han ◽  
Baohong Guo ◽  
...  
Keyword(s):  
Gas Flow ◽  
High Rate ◽  
Stable Operation ◽  
Beam Test ◽  
High Luminosity ◽  
Rate Test ◽  
3D Printed ◽  
Resistive Plate Chambers ◽  
The Impact ◽  
Current Behavior

This work reports the latest observations on the behavior of two Multigap Resistive Plate Chambers (MRPC) under wide high-luminosity exposures, which motivate the development and in-beam test of the sealed MRPC prototype assembled with low-resistive glass. The operation currently being monitored, together with previous simulation results, shows the impact of gas pollution caused by avalanches in gas gaps, and the necessity to shrink the gas-streaming volume. With the lateral edge of the detector sealed by a 3D-printed frame, a reduced gas-streaming volume of ~170 mL has been achieved for a direct gas flow to the active area. A high-rate test of the sealed MRPC prototype shows that, ensuring a 97% efficiency and 70 ps time resolution, the sealed design results in a stable operation current behavior at a counting rate of 3–5 kHz/cm2. The sealed MRPC will become a potential solution for future high luminosity applications.

scholarly journals The Impact of an Inactivated Hepatitis A Vaccine with One Dose in Brazil: A Retrospective Time-Series

Vaccines ◽  
2021 ◽  
Vol 9 (4) ◽  
pp. 407
Author(s):  
Ana Luiza Bierrenbach ◽  
Yoonyoung Choi ◽  
Paula de Mendonça Batista ◽  
Fernando Brandão Serra ◽  
Cintia Irene Parellada ◽  
...  
Keyword(s):  
Time Series ◽  
Time Series Analysis ◽  
Hepatitis A ◽  
National Level ◽  
Age Groups ◽  
High Rate ◽  
Series Analysis ◽  
Annual Reduction ◽  
The Impact ◽  
Vaccination Period

Background: In 2014, a recommended one-dose of inactivated hepatitis A vaccine was included in the Brazilian National Immunization Program targeting children 12–24 months. This decision addressed the low to intermediate endemicity status of hepatitis A across Brazil and the high rate of infection in children and adolescents between 5 and 19 years old. The aim of the study was to conduct a time-series analysis on hepatitis A incidence across age groups and to assess the hepatitis A distribution throughout Brazilian geographic regions. Methods: An interrupted time-series analysis was performed to assess hepatitis A incidence rates before (2010–2013) and after (2015–2018) hepatitis A vaccine program implementation. The time-series analysis was stratified by age groups while a secondary analysis examined geographic distribution of hepatitis A cases. Results: Overall incidence of hepatitis A decreased from 3.19/100.000 in the pre-vaccine period to 0.87/100.000 (p = 0.022) post-vaccine introduction. Incidence rate reduction was higher among children aged 1-4 years old, with an annual reduction of 67.6% in the post-vaccination period against a 7.7% annual reduction in the pre-vaccination period (p < 0.001). Between 2015 and 2018, the vaccination program prevented 14,468 hepatitis A cases. Conclusion: Our study highlighted the positive impact of a recommended one-dose inactivated hepatitis A vaccine for 1–4-years-old in controlling hepatitis A at national level.

scholarly journals Exploring the effectiveness of a COVID-19 contact tracing app using an agent-based model

2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Jonatan Almagor ◽  
Stefano Picascia
Keyword(s):  
High Rate ◽  
Contact Tracing ◽  
Agent Based Model ◽  
Agent Based ◽  
The Social ◽  
Behavioural Factors ◽  
The Impact ◽  
Different Levels ◽  
User Rate

AbstractA contact-tracing strategy has been deemed necessary to contain the spread of COVID-19 following the relaxation of lockdown measures. Using an agent-based model, we explore one of the technology-based strategies proposed, a contact-tracing smartphone app. The model simulates the spread of COVID-19 in a population of agents on an urban scale. Agents are heterogeneous in their characteristics and are linked in a multi-layered network representing the social structure—including households, friendships, employment and schools. We explore the interplay of various adoption rates of the contact-tracing app, different levels of testing capacity, and behavioural factors to assess the impact on the epidemic. Results suggest that a contact tracing app can contribute substantially to reducing infection rates in the population when accompanied by a sufficient testing capacity or when the testing policy prioritises symptomatic cases. As user rate increases, prevalence of infection decreases. With that, when symptomatic cases are not prioritised for testing, a high rate of app users can generate an extensive increase in the demand for testing, which, if not met with adequate supply, may render the app counterproductive. This points to the crucial role of an efficient testing policy and the necessity to upscale testing capacity.

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