Comparative Evaluation of the Polar Organic Chemical Integrative Sampler (POCIS) in Two Types of Validation Systems

2021 ◽  
Author(s):  
Kazushi Noro ◽  
Etiënne L. M. Vermeirssen ◽  
Arisa Banno ◽  
Junko Ono ◽  
Yoshinori Yabuki
Keyword(s):  
Natural Water ◽  
Tap Water ◽  
Low Cost ◽  
Weighted Average ◽  
Organic Chemical ◽  
Average Value ◽  
Data Points ◽  
Time Weighted Average ◽  
Few Data ◽  
Neonicotinoid Pesticides

<p>Polar organic chemical integrative sampler (POCIS) devices have been suggested for monitoring contaminant fluctuations in aquatic environments, resulting from chemical leak accidents. However, the response of the POCIS device in the emergency condition in natural water remains unclear. The response of the POCIS device to contaminant fluctuation was investigated using a simplified chamber test with tap water and a channel test with natural water in the present study. The fluctuation in the chamber and the channel replicated the condition of river water under a chemical leak scenario (maximum concentration: 1–10 μg L<sup>–1</sup>, half-life: 1 d). The target chemicals were neonicotinoid pesticides (dinotefuran, clothianidin, thiamethoxam, imidacloprid, acetamiprid, and thiacloprid) and bisphenol A. The ratio of the POCIS measured value to the time-weighted average value of grab samplings (POCIS/TWA) for the channel test (temperature: 15 °C, flow velocity: 15 cm s<sup>–1</sup>) ranged from 61% (clothianidin) to 133% (thiacloprid). The results indicated that the POCIS device could be effectively used as a monitoring device in an aquatic environment under the chemical leak scenario. In addition, the differences in the POCIS/TWA ratios obtained from the chamber test and the channel test were in the range of –50 to 50%, except for a few data points. Thus, the simplified chamber test could be used as a validation system to evaluate the POCIS device at a low cost.</p>

Comparative Evaluation of the Polar Organic Chemical Integrative Sampler (POCIS) in Two Types of Validation Systems

2021 ◽  
Author(s):  
Kazushi Noro ◽  
Etiënne L. M. Vermeirssen ◽  
Arisa Banno ◽  
Junko Ono ◽  
Yoshinori Yabuki
Keyword(s):  
Natural Water ◽  
Tap Water ◽  
Low Cost ◽  
Weighted Average ◽  
Organic Chemical ◽  
Average Value ◽  
Data Points ◽  
Time Weighted Average ◽  
Few Data ◽  
Neonicotinoid Pesticides

<p>Polar organic chemical integrative sampler (POCIS) devices have been suggested for monitoring contaminant fluctuations in aquatic environments, resulting from chemical leak accidents. However, the response of the POCIS device in the emergency condition in natural water remains unclear. The response of the POCIS device to contaminant fluctuation was investigated using a simplified chamber test with tap water and a channel test with natural water in the present study. The fluctuation in the chamber and the channel replicated the condition of river water under a chemical leak scenario (maximum concentration: 1–10 μg L<sup>–1</sup>, half-life: 1 d). The target chemicals were neonicotinoid pesticides (dinotefuran, clothianidin, thiamethoxam, imidacloprid, acetamiprid, and thiacloprid) and bisphenol A. The ratio of the POCIS measured value to the time-weighted average value of grab samplings (POCIS/TWA) for the channel test (temperature: 15 °C, flow velocity: 15 cm s<sup>–1</sup>) ranged from 61% (clothianidin) to 133% (thiacloprid). The results indicated that the POCIS device could be effectively used as a monitoring device in an aquatic environment under the chemical leak scenario. In addition, the differences in the POCIS/TWA ratios obtained from the chamber test and the channel test were in the range of –50 to 50%, except for a few data points. Thus, the simplified chamber test could be used as a validation system to evaluate the POCIS device at a low cost.</p>

scholarly journals Lead Ions Removal from Natural Water Samples by Nano-Mint Waste as Benign Low Cost Biosorbent

2018 ◽  
Vol 3 (2) ◽  
pp. 116-126
Author(s):  
Tamer H. A. Hasanin ◽  
Salwa A. Ahmed ◽  
Taghreed B. Ebrahim
Keyword(s):  
Natural Water ◽  
Water Samples ◽  
Metal Ion ◽  
Sea Water ◽  
Tap Water ◽  
Low Cost ◽  
Lead Removal ◽  
Lead Uptake ◽  
Natural Water Samples ◽  
Uptake Process

Nano mint waste (NMW) was used as a low-cost nano biosorbent and efficient Pb(II) remover. pH, contact time, biosorbent dose, and concentration of metal ion were optimized using batch technique to optimize maximum capacity of this new biosorbent. NMW was characterized using FT-IR, SEM, TEM, and XRD analyses. The experimental Pb(II) adsorption data by NMW were agreed with both Freundlich and Langmuir models with maximum boisorption capacity of 2.13 mmolg-1 (441.336 mgg-1). In addition, values of lead uptake at different time vaues was best fitted with the kinetic pseudo-second order model. It will be notable that, good data resulted from the kinetic experiments study confirmed a fast accessibility of the Pb(II) to the biosorbent surface, get to equilibrium within 30 seconds. On the other hand, it was observed that, the developed method, was investigated for measuring of Pb(II) with a certain spiked amounts in natural water samples as ground water (GW), sea water (SW), drinking tap water (DTW), natural drinking water (NDW), Nile River water (NRW) and waste water (WW). The good results obtained with high recovered quantitatively using batch experiments, without matrix interferences. Considering its cheap source, environmentally friendly, economic and fast uptake process, NMW can be used as benign nano biosorbent for lead removal from real water samples.

scholarly journals Faking Signals to Fool Deep Neural Networks in AMC via Few Data Points

IEEE Access ◽  
2021 ◽  
pp. 1-1
Author(s):  
Hongbin Ma ◽  
Shuyuan Yang ◽  
Guangjun He ◽  
Ruowu Wu ◽  
Xiaojun Hao ◽  
...  
Keyword(s):  
Neural Networks ◽  
Deep Neural Networks ◽  
Data Points ◽  
Few Data

scholarly journals A Person-to-Person and Person-to-Place COVID-19 Contact Tracing System Based on OGC IndoorGML

2020 ◽  
Vol 10 (1) ◽  
pp. 2 ◽  
Author(s):  
Soroush Ojagh ◽  
Sara Saeedi ◽  
Steve H. L. Liang
Keyword(s):  
Data Model ◽  
Low Cost ◽  
Large Body ◽  
Contact Tracing ◽  
Trajectory Data ◽  
Sequential Order ◽  
Human Contact ◽  
Wide Availability ◽  
Data Points ◽  
The Impact

With the wide availability of low-cost proximity sensors, a large body of research focuses on digital person-to-person contact tracing applications that use proximity sensors. In most contact tracing applications, the impact of SARS-CoV-2 spread through touching contaminated surfaces in enclosed places is overlooked. This study is focused on tracing human contact within indoor places using the open OGC IndoorGML standard. This paper proposes a graph-based data model that considers the semantics of indoor locations, time, and users’ contexts in a hierarchical structure. The functionality of the proposed data model is evaluated for a COVID-19 contact tracing application with scalable system architecture. Indoor trajectory preprocessing is enabled by spatial topology to detect and remove semantically invalid real-world trajectory points. Results show that 91.18% percent of semantically invalid indoor trajectory data points are filtered out. Moreover, indoor trajectory data analysis is innovatively empowered by semantic user contexts (e.g., disinfecting activities) extracted from user profiles. In an enhanced contact tracing scenario, considering the disinfecting activities and sequential order of visiting common places outperformed contact tracing results by filtering out unnecessary potential contacts by 44.98 percent. However, the average execution time of person-to-place contact tracing is increased by 58.3%.

scholarly journals Treatment of thoracolumbar burst fractures: extended follow-up of a randomized clinical trial comparing orthosis versus no orthosis

2017 ◽  
Vol 27 (1) ◽  
pp. 42-47 ◽  
Author(s):  
Jennifer C. Urquhart ◽  
Osama A. Alrehaili ◽  
Charles G. Fisher ◽  
Alyssa Fleming ◽  
Parham Rasoulinejad ◽  
...  
Keyword(s):  
Outcome Measures ◽  
Weighted Average ◽  
Average Treatment Effect ◽  
Secondary Outcome ◽  
Thoracolumbar Burst Fractures ◽  
Treatment Comparison ◽  
Average Treatment ◽  
Burst Fractures ◽  
Time Weighted Average

OBJECTIVEA multicenter, prospective, randomized equivalence trial comparing a thoracolumbosacral orthosis (TLSO) to no orthosis (NO) in the treatment of acute AO Type A3 thoracolumbar burst fractures was recently conducted and demonstrated that the two treatments following an otherwise similar management protocol are equivalent at 3 months postinjury. The purpose of the present study was to determine whether there was a difference in long-term clinical and radiographic outcomes between the patients treated with and those treated without a TLSO. Here, the authors present the 5- to 10-year outcomes (mean follow-up 7.9 ± 1.1 years) of the patients at a single site from the original multicenter trial.METHODSBetween July 2002 and January 2009, a total of 96 subjects were enrolled in the primary trial and randomized to two groups: TLSO or NO. Subjects were enrolled if they had an AO Type A3 burst fracture between T-10 and L-3 within the previous 72 hours, kyphotic deformity < 35°, no neurological deficit, and an age of 16–60 years old. The present study represents a subset of those patients: 16 in the TLSO group and 20 in the NO group. The primary outcome measure was the Roland Morris Disability Questionnaire (RMDQ) score at the last 5- to 10-year follow-up. Secondary outcome measures included kyphosis, satisfaction, the Numeric Rating Scale for back pain, and the 12-Item Short-Form Health Survey (SF-12) Mental and Physical Component Summary (MCS and PCS) scores. In the original study, outcome measures were administered at admission and 2 and 6 weeks, 3 and 6 months, and 1 and 2 years after injury; in the present extended follow-up study, the outcome measures were administered 5–10 years postinjury. Treatment comparison between patients in the TLSO group and those in the NO group was performed at the latest available follow-up, and the time-weighted average treatment effect was determined using a mixed-effects model of longitudinal regression for repeated measures averaged over all time periods. Missing data were assumed to be missing at random and were replaced with a set of plausible values derived using a multiple imputation procedure.RESULTSThe RMDQ score at 5–10 years postinjury was 3.6 ± 0.9 (mean ± SE) for the TLSO group and 4.8 ± 1.5 for the NO group (p = 0.486, 95% CI −2.3 to 4.8). Average kyphosis was 18.3° ± 2.2° for the TLSO group and 18.6° ± 3.8° for the NO group (p = 0.934, 95% CI −7.8 to 8.5). No differences were found between the NO and TLSO groups with time-weighted average treatment effects for RMDQ 1.9 (95% CI −1.5 to 5.2), for PCS −2.5 (95% CI −7.9 to 3.0), for MCS −1.2 (95% CI −6.7 to 4.2) and for average pain 0.9 (95% CI −0.5 to 2.2).CONCLUSIONSCompared with patients treated with a TLSO, patients treated using early mobilization without orthosis maintain similar pain relief and improvement in function for 5–10 years.

scholarly journals Considerations of the Scale of Radiocarbon Offsets in the East Mediterranean, and Considering a Case for the Latest (Most Recent) Likely Date for the Santorini Eruption

Radiocarbon ◽  
2012 ◽  
Vol 54 (3-4) ◽  
pp. 449-474 ◽  
Author(s):  
Sturt W Manning ◽  
Bernd Kromer
Keyword(s):  
Time Horizon ◽  
Weighted Average ◽  
17Th Century ◽  
Data Sets ◽  
East Mediterranean ◽  
Average Value ◽  
Accuracy And Precision ◽  
Wide Range ◽  
The Impact ◽  
East Mediterranean Region

The debate over the dating of the Santorini (Thera) volcanic eruption has seen sustained efforts to criticize or challenge the radiocarbon dating of this time horizon. We consider some of the relevant areas of possible movement in the14C dating—and, in particular, any plausible mechanisms to support as late (most recent) a date as possible. First, we report and analyze data investigating the scale of apparent possible14C offsets (growing season related) in the Aegean-Anatolia-east Mediterranean region (excluding the southern Levant and especially pre-modern, pre-dam Egypt, which is a distinct case), and find no evidence for more than very small possible offsets from several cases. This topic is thus not an explanation for current differences in dating in the Aegean and at best provides only a few years of latitude. Second, we consider some aspects of the accuracy and precision of14C dating with respect to the Santorini case. While the existing data appear robust, we nonetheless speculate that examination of the frequency distribution of the14C data on short-lived samples from the volcanic destruction level at Akrotiri on Santorini (Thera) may indicate that the average value of the overall data sets is not necessarily the most appropriate14C age to use for dating this time horizon. We note the recent paper of Soter (2011), which suggests that in such a volcanic context some (small) age increment may be possible from diffuse CO2emissions (the effect is hypothetical at this stage and hasnotbeen observed in the field), and that "if short-lived samples from the same stratigraphic horizon yield a wide range of14C ages, the lower values may be the least altered by old CO2." In this context, it might be argued that a substantive “low” grouping of14C ages observable within the overall14C data sets on short-lived samples from the Thera volcanic destruction level centered about 3326–3328 BP is perhaps more representative of the contemporary atmospheric14C age (without any volcanic CO2contamination). This is a subjective argument (since, in statistical terms, the existing studies using the weighted average remain valid) that looks to support as late a date as reasonable from the14C data. The impact of employing this revised14C age is discussed. In general, a late 17th century BC date range is found (to remain) to be most likelyeven ifsuch a late-dating strategy is followed—a late 17th century BC date range is thus a robust finding from the14C evidence even allowing for various possible variation factors. However, the possibility of a mid-16th century BC date (within ∼1593–1530 cal BC) is increased when compared against previous analyses if the Santorini data are considered in isolation.

Mocvd SrS:Ce for Applications in Electroluminescent Devices

1997 ◽  
Vol 471 ◽  
Author(s):  
D. Endisch ◽  
K. Barth ◽  
J. Lau ◽  
G. Peterson ◽  
A. E. Kaloyeros ◽  
...  
Keyword(s):  
Process Development ◽  
Process Integration ◽  
Low Cost ◽  
Chemical Vapor ◽  
High Growth ◽  
Film Structure ◽  
High Growth Rate ◽  
Organic Chemical ◽  
Glass Substrates ◽  
Full Color

ABSTRACTSrS:Ce is an important material for full color electroluminescent (EL) flat panel displays. Using a combination of SrS:Ce/ZnS:Mn and appropriate color filters high quality full color displays have been demonstrated [1]. Major issues for commercially viable process integration of SrS:Ce are the combination of high luminance, high growth rate, and process temperatures below 600°C for compatibility with low cost glass substrates. This work describes the process development and optimization of metal-organic chemical vapor deposition (MOCVD) of SrS:Ce. MOCVD is a promising candidate for deposition of SrS:Ce because it can provide the required growth rates and allows control of crystal structure and stoichiometry. Growth of SrS:Ce was performed in the temperature range from 400°C to 530°C using Sr(tmhd)2, Ce(tmhd)4, and H2S as precursors. The structure of the SrS:Ce was found to be strongly dependent on the H2S flow. A brightness of 15 fL and an efficiency of 0.22 lm/W has been achieved (40 V above threshold voltage, 60 Hz AC). Film analysis included Rutherford backscattering (RBS), X-ray diffraction (XRD), atomic force microscopy (AFM), and EL measurements. Results on the correlation between process parameters, film structure, grain size and EL performance will be presented.

CHANGES IN THE TECHNICAL AND TECHNOLOGICAL LEVEL OF STEAM CULTIVATORS IN THE XXI CENTURY

2021 ◽  
Vol 2 (143) ◽  
pp. 174-183
Author(s):  
Andrey Yu. Nesmiyan ◽  
◽  
Anastasiya S. Kaymakova ◽  
Yuliya S. Tsench ◽  
Keyword(s):  
Weighted Average ◽  
Specific Weight ◽  
Research Purpose ◽  
Utilization Rate ◽  
Average Value ◽  
Technological Level ◽  
Short Test ◽  
Specific Material ◽  
The Cost

Most modern agricultural machines and tools consist of components, the main parameters, design features of which were justified in the first half of the twentieth century. Slowly and evolutionarily, these technical means are developing. (Research purpose) The research purpose is in identifying general trends in the technical and technological level of steam cultivators in the first quarter of the XXI century. (Materials and Methods) For the study there was analyzed the data of the short test reports of the selected machines. The production of steam cultivators in the Russian Federation is gradually increasing. (Results and discussion) For ten years of the beginning of the XXI century, only 27 machines were provided for testing, and from 2014 to 2017 – more than 40, while for "old" cultivators, the weighted average value of the tractor traction class was 2.8, for new ones it is about of four. For the study period (on average 10 years) the quality of soil cultivation in terms of such parameters as deviation from the specified depth of cultivation, crumbling and combing of the field surface has not changed much. The productivity of cultivator units increased by 7-21 percents, which is explained not only by an increase in the power of tractors, but also by an increase in the utilization rate of charge time on average from 0.72 to 0.77. The specific weight of the "new" cultivators was on average 22 kilogram-meters less than that of the "old" analogues, which can be explained by the evolution of their designs. (Conclusions) Increasing the class of tractors by one "level" the specific material consumption of the cultivators aggregated with them increases by about 58 kilogram-meters for both "old" and " new " cultivators. With an increase in the width of the tools from 4 to 16 meters, their weight will increase by 8 times, which affects the cost and operational and environmental characteristics of wide-reach cultivators.

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