36 research outputs found
The Influence of Salinity, pH, Temperature and Particles on Produced Water Oil Quantification Precision and Accuracy with Confocal Laser Fluorescence Microscopy
The present study
investigates the effects of different produced
water parameters, such as salinity, pH, temperature, and presence
of colloidal particles, in oil quantification using confocal laser
fluorescence microscopy (CLFM). The study simulates different produced
water samples, which typically contains a mixture of oil, salts, and
different concentrations of particles. The accuracy of the quantification
was not affected by the environmental condition for any of the conditions
investigated. On the other hand, under extreme environmental conditions,
such as high pH (pH 8), salinity (250000 ppm), and temperatures (60
°C), the precision of the CLFM oil quantification was reduced.
Changes in the average oil droplet size upon variation of the environmental
conditions generally correlated with the change in CLFM measurement
precision. Interfacial tension and DLVO interactions were further
evaluated to gain a better mechanistic understanding of how the environmental
conditions affect the size or colloidal stability of the oil droplets
and therefore impact the precision of CLFM measurements. To obtain
an overall understanding of the relationship of the different environmental
parameters and oil droplet properties with the level of CLFM measurement
precision, multiple correspondence analysis (MCA) and multiple regression
analysis were employed. The results showed that conditions of lower
salinity, temperature, and SiO<sub>2</sub> concentration, as well
as neutral pH (pH 7), favor smaller oil droplet sizes (close to 4
μm) in the oil-in-water emulsion and more precise CLFM measurements.
The better understanding of the impact of different water chemistries
on oil droplet stability will be essential for decision-makers on
conditions that could impact the precision of the method. This work
presents a new perspective of investigating CLFM as an oil-in-water
quantification technology and guidance for engineers operating this
novel technology on the optimum environmental conditions to achieve
the best performance of the technology
Classification and regression tree analysis of smoking and genetic polymorphism.
<p>Terminal nodes show numbers of CWP patients/numbers of controls. Single nucleotide polymorphisms were classified as wild type (W) and variant genotype (V); smoking was defined according to pack-years smoked.</p
Frequency distributions of the combined genotypes between CWP cases and controls.
a<p>Adjusted for age, exposure years, pack-years smoked, and job type.</p
Demographic and selected variables among the CWP cases and control subjects.
<p>Demographic and selected variables among the CWP cases and control subjects.</p
MDR analysis for the CWP risk predication.
<p>MDR analysis for the CWP risk predication.</p
Distributions of genotypes and their associations with risk of CWP.
a<p>Two-sided x2 test.</p>b<p>Adjusted for age, exposure years, pack-years smoked, and job type.</p
Primary information of genotyped SNPs.
<p>HWE<sup>a</sup> (Hardy–Weinberg equilibrium) <i>P</i> value in the control group.</p
Data_Sheet_1_Twenty-four hour variability of inverted T-waves in patients with apical hypertrophic cardiomyopathy.pdf
BackgroundPatients with apical hypertrophic cardiomyopathy (ApHCM) have marked inverted T-waves that vary over several years. Inverted T-waves in ApHCM are unstable, but it is unclear whether this change is due to coronary artery disease (CAD) or if it is a characteristic of ApHCM itself. We aimed to study the characteristics of inverted T-waves in patients with ApHCM over the course of 24 h to improve the diagnostic indices of ApHCM.MethodsWe examined 83 patients with ApHCM and 89 patients with CAD (who served as the control group). All patients underwent a 24-h dynamic electrocardiogram (ECG). We analyzed the average depth of inverted T-waves per minute and sorted them from shallow to deep; the sorted ECG segments at the 10th, 50th, and 90th positions of the T-wave were subsequently analyzed.ResultsThe amplitudes of inverted T-waves in ApHCM corresponding to the 10th, 50th, and 90th percentiles were −5.13 ± 4.11, −8.10 ± 4.55, and −10.9 ± 5.04 mm, respectively. Changes in the degree of inverted T-waves were greater in ApHCM than in CAD. T-wave amplitudes in ApHCM were strongly associated with heart rate and circadian rhythm and only weakly associated with CAD and posture. Maximum T-wave amplitudes in the CAD group were 10 mm, and all patients with ApHCM aged 10 mm.ConclusionNotable variations in the T-waves of patients with ApHCM were observed over 24 h. ECG examinations during states of inactivity (comparable to sleep) improved the sensitivity of the diagnosis of ApHCM. Inverted T-wave amplitudes correlated with heart rate and circadian rhythm, where T-wave changes in ApHCM may be due to the normalization of abnormal T-waves effect. Identifying T-wave amplitudes >10 mm can effectively improve the diagnostic rate of ApHCM, especially in patients aged <50 years. The short-term change in T-waves in patients with ApHCM could serve as a novel index that will help in the diagnosis of ApHCM.</p
Demographic and selected variables among the CWP cases and control subjects.
<p>Demographic and selected variables among the CWP cases and control subjects.</p
Distributions of genotypes of inflammasome genes and their associations with risk of CWP.
a<p>Two-sided χ<sup>2</sup> test.</p>b<p>Adjusted for age, exposure years, and pack-years of smoking in logistic regression model.</p