PCDD/Fs are Persistent Organic Pollutants (POPs), generated by incomplete combustion of carbonaceous and chlorinated compounds. Because of their toxicity, they have to be monitored at emission, from stationary sources like waste incinerator. In the framework of the development of an on-line analyser, the laboratory prototype requires a gaseous dioxin source. We detail the principles of a dynamic generator based on the sublimation of solid sample and on the diffusion method. Such a device has to supply a polluted flow at steady and adjustable concentration of dioxin. The dioxin generation rate is determined by the weight loss of the solid sample. It is constant during time for temperatures ranging between 75 and 100°C and for generation flow rates greater than or equal to 50 mL min(-1). Variation of generation rate with temperature is predictable. With the increasing of temperature, emitted concentration increases while the increase of the inlet pressure decreases the concentration. Helium carrier gas leads to a higher generation rate than with N2 in agreement with mass and molecular volume ratio. Thus, the outlet concentration and flow rate can be settled independently in the range of 3-100 ppm and 50-200 mL min(-1).
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http://dx.doi.org/10.1016/j.chemosphere.2013.12.013 | DOI Listing |
Jpn J Clin Oncol
January 2025
Department of Otorhinolaryngology, Head and Neck Surgery, Yokohama City University, School of Medicine, Yokohama, Japan.
The prognosis for T2N0 glottic squamous cell carcinoma (SCC) is generally favorable, with a 5-year overall survival rate of 79%-96% achieved with radiotherapy (RT), the standard nonsurgical treatment for this condition. However, the local control rate for T2N0 glottic SCC treated with RT remains suboptimal, with a 5-year local control rate of only 65%-80%. Local residual disease or recurrence following RT for T2N0 glottic SCC often leads to difficulties in laryngeal preservation.
View Article and Find Full Text PDFEJNMMI Phys
January 2025
Department of Medical Radiation Physics and Nuclear Medicine, Karolinska University Hospital, Solna, Sweden.
Background: System calibration is essential for accurate SPECT/CT dosimetry. However, count losses due to dead time and pulse pileup may cause calibration errors, in particular for I, where high count rates may be encountered. Calibration at low count rates should also be avoided to minimise detrimental effects from e.
View Article and Find Full Text PDFJ Infect Dev Ctries
December 2024
Nephrology Department, UHC Mother Tereza, Tirane, Albania.
Introduction: Acute kidney injury involves inflammation and intrinsic renal damage, and is a common complication of severe coronavirus disease 2019 (COVID-19). Baseline chronic kidney disease (CKD) confers an increased mortality risk. We determined the renal long-term outcomes of COVID-19 in patients with baseline CKD, and the risk factors prompting renal replacement therapy (RRT) initiation and mortality.
View Article and Find Full Text PDFBMC Pulm Med
January 2025
Department of Key Laboratory of Ningxia Stem Cell and Regenerative Medicine, Institute of Medical Sciences, Department of Pulmonary and Critical Care Medicine, General Hospital of Ningxia Medical University, Yinchuan, Ningxia, 750004, China.
Background: In this study, we aimed to explore the association between baseline and early changes in the neutrophil-to-lymphocyte ratio (NLR) and the 30-day mortality rate in patients having anti-melanoma differentiation-associated gene 5 (MDA5)-positive dermatomyositis with interstitial lung disease (DM-ILD).
Methods: Overall, 263 patients with anti-MDA5 DM-ILD from four centers in China were analyzed. Multivariate logistic regression analysis was used to evaluate the impact of baseline NLR on the 30-day mortality rate in patients with anti-MDA5-positive DM-ILD.
BMC Prim Care
January 2025
Division of Family Medicine and Primary Care, Department of Neurobiology, Care Sciences and Society, Karolinska Institutet, Huddinge, Sweden.
Aims: To study differences in cardiovascular prevention and hypertension management in primary care in men and women, with comparisons between public and privately operated primary health care (PHC).
Methods: We used register data from Region Stockholm on collected prescribed medication and registered diagnoses, to identify patients aged 30 years and above with hypertension. Age-adjusted logistic regression was used to calculate odds ratios (ORs) with 99% confidence intervals (99% CIs) using public PHC centers as referents.
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