Effects of gas–wall partitioning in Teflon tubing and instrumentation on time-resolved measurements of gas-phase organic compounds

Recent studies have demonstrated that organic compounds can partition from the gas phase to the walls in Teflon environmental chambers and that the process can be modeled as absorptive partitioning. Here these studies were extended to investigate gas–wall partitioning of organic compounds in Teflon tubing and inside a proton-transfer-reaction mass spectrometer (PTR-MS) used to monitor compound concentrations. Rapid partitioning of C8–C14 2-ketones and C11–C16 1-alkenes was observed for compounds with saturation concentrations (c∗) in the range of 3 × 104 to 1 × 107 µg m−3, causing delays in instrument response to step-function changes in the concentration of compounds being measured. These delays vary proportionally with tubing length and diameter and inversely with flow rate and c∗. The gas–wall partitioning process that occurs in tubing is similar to what occurs in a gas chromatography column, and the measured delay times (analogous to retention times) were accurately described using a linear chromatography model where the walls were treated as an equivalent absorbing mass that is consistent with values determined for Teflon environmental chambers. The effect of PTR-MS surfaces on delay times was also quantified and incorporated into the model. The model predicts delays of an hour or more for semivolatile compounds measured under commonly employed conditions. These results and the model can enable better quantitative design of sampling systems, in particular when fast response is needed, such as for rapid transients, aircraft, or eddy covariance measurements. They may also allow estimation of c∗ values for unidentified organic compounds detected by mass spectrometry and could be employed to introduce differences in time series of compounds for use with factor analysis methods. Best practices are suggested for sampling organic compounds through Teflon tubing

Changes in saliva analytes in dairy cows during peripartum: A pilot study

This pilot study aimed to study the possible changes in a profile of 26 salivary analytes in thirteen healthy dairy cows along their peripartum period. Analytes associated with the stress (salivary cortisol, salivary alpha-amylase, butyrylcholinesterase, and total esterase), inflammation (adenosine deaminase), oxidative status (total antioxidant capacity and the advanced oxidation protein products), and general metabolism (creatine kinase, γ-glutamyl transferase, urea, triglycerides, glucose, and lactate) varied along the sampling times. A positive correlation between the white blood cells counts, and the lipase, Trolox equivalent antioxidant capacity, advanced oxidation protein products, and lactate levels in saliva were observed at the delivery. A linear association between selected salivary analytes at different sampling times and the milk yield after calving was observed. In conclusion, in our experimental conditions, it was observed that the peripartum period in dairy cows can induce changes in salivary analytes. Some of them were associated with inflammatory status and the capacity of milk production after calving

Quality of Life of Oligometastatic and Polymetastatic Head and Neck Squamous Cell Carcinoma Patients

Objective: Evidence suggests that distant metastasis in head and neck squamous cell carcinoma is a spectrum of disease. Previous studies show that oligometastasis has favorable survival compared with polymetastasis. The quality of life of patients with oligometastasis remains unknown. To further solidify the position of oligometastasis as a separate entity, we hypothesized that oligometastatic patients experience better quality of life than polymetastatic patients.Methods: Patients with distant metastasis were stratified into three groups: oligometastasis (≤3 metastatic foci in ≤2 anatomic sites), explosive metastasis (≥4 metastatic foci at one anatomic site), and explosive-disseminating metastasis (spread to ≥3 anatomic sites). Quality of life was assessed every 2 months post distant metastasis diagnosis. Results: Between January 1, 2016, and December 31, 2021, a total of 161 patients with distant metastasis were identified, with a total of 397 measurements. In this group, 57 (35.4%) patients had oligometastasis, 35 (21.7%) patients had explosive metastasis, and 69 (42.9%) patients had explosive-disseminating metastasis. Their median post-distant metastasis survivals were 8.5 months, 3.2 months, and 3.2 months respectively (p &lt; 0.001). A significantly better overall quality of life was observed in the oligometastasis group compared with the polymetastatic groups (+0.75 out of 7, p &lt; 0.05). Furthermore, oligometastatic patients performed better in the subdomains of “physical functioning,” “fatigue,” and “pain.”. Conclusion: Results from this study underscore that subgroups exist regarding quality of life and survival within distant metastasis, with polymetastatic patients performing worse than oligometastatic patients. This highlights the significance of tailored interventions that consider the unique challenges faced by each metastatic group of patients. Level of Evidence: 3, retrospective cohort study Laryngoscope, 2024.</p

Triploidy induction by heat-shock treatment in red tilapia

The possible use of sterile triploid red tilapia is an interesting option for culture due to their proliferating breeding activities. The aim of the present study was to investigate and optimize the time of heat-shock treatment to prevent second polar body extrusion from the newly fertilized eggs of red tilapia, to produce a maximum number of triploid individuals. Heat-shock treatment was applied at a temperature of 41 degrees C for a total duration of 3.5 minutes after 2, 3, 4, 4.5, 5 and 6 minutes of fertilization. The best survival rate (67.0) and triploid percentage (89.7) was observed for the treatment at 4 minutes after fertilization. It is thus successfully demonstrated that 4 minutes after fertilization was the most suitable timing of heat-shock treatment for second polar body retention in newly fertilized eggs of red tilapia

User Interaction in Semi-Automatic Segmentation of Organs at Risk: a Case Study in Radiotherapy

Accurate segmentation of organs at risk is an important step in radiotherapy planning. Manual segmentation being a tedious procedure and prone to inter- and intra-observer variability, there is a growing interest in automated segmentation methods. However, automatic methods frequently fail to provide satisfactory result, and post-processing corrections are often needed. Semi-automatic segmentation methods are designed to overcome these problems by combining physicians’ expertise and computers’ potential. This study evaluates two semi-automatic segmentation methods with different types of user interactions, named the “strokes” and the “contour”, to provide insights into the role and impact of human-computer interaction. Two physicians participated in the experiment. In total, 42 case studies were carried out on five different types of organs at risk. For each case study, both the human-computer interaction process and quality of the segmentation results were measured subjectively and objectively. Furthermore, different measures of the process and the results were correlated. A total of 36 quantifiable and ten non-quantifiable correlations were identified for each type of interaction. Among those pairs of measures, 20 of the contour method and 22 of the strokes method were strongly or moderately correlated, either directly or inversely. Based on those correlated measures, it is concluded that: (1) in the design of semi-automatic segmentation methods, user interactions need to be less cognitively challenging; (2) based on the observed workflows and preferences of physicians, there is a need for flexibility in the interface design; (3) the correlated measures provide insights that can be used in improving user interaction design

Dynamics of Higher Spin Fields and Tensorial Space

The structure and the dynamics of massless higher spin fields in various dimensions are reviewed with an emphasis on conformally invariant higher spin fields. We show that in D=3,4,6 and 10 dimensional space-time the conformal higher spin fields constitute the quantum spectrum of a twistor-like particle propagating in tensorial spaces of corresponding dimensions. We give a detailed analysis of the field equations of the model and establish their relation with known formulations of free higher spin field theory.Comment: JHEP3 style, 40 pages; v2 typos corrected, comments and references added; v3 published versio

Pumping current of a Luttinger liquid with finite length

We study transport properties in a Tomonaga-Luttinger liquid in the presence of two time-dependent point like weak impurities, taking into account finite-length effects. By employing analytical methods and performing a perturbation theory, we compute the backscattering pumping current (I_bs) in different regimes which can be established in relation to the oscillatory frequency of the impurities and to the frequency related to the length and the renormalized velocity (by the electron-electron interactions) of the charge density modes. We investigate the role played by the spatial position of the impurity potentials. We also show how the previous infinite length results for I_bs are modified by the finite size of the system.Comment: 9 pages, 7 figure

Documentation of Subtype C HIV Type 1 Strains in Argentina, Paraguay and Uruguay.

HIV subtypes B, F, and BF recombinants have been previously reported in South America. This report describes the presence of HIV-1 subtype C infection in the countries of Argentina, Uruguay, and Paraguay dating back to at least 1999. Surveillance for uncommon non-B/non-F subtype viruses circulating in South America has been conducted in samples obtained from nine countries. Peripheral blood mononuclear cells (PBMC), dried filter paper (FP), and fresh blood (FB) samples were collected from HIV-positive patients from Ecuador, Colombia, Venezuela, Peru, Chile, Bolivia, Argentina, Uruguay, and Paraguay. From a total of 2962 HIV seropositive samples examined during a 9-year period (1995-2003), only 11 (0.4%) were found to be infected with non-B/non-F HIV variants. Eight of these 11 strains were determined to be subtype C by heteroduplex mobility assay (HMA). Five of these 8 strains were further characterized by sequencing and phylogenetic analysis of the protease (Pro) and reverse transcriptase (RT) region of the genome and two were sequenced full length. One of the strains was found to be a unique BC recombinant. The spread of a third subtype of HIV, subtype C, should raise the question of its potential future role in the HIV epidemic in this region.Fil: Carrion, G.. U.S. Naval Medical Research Center Detachment; PerúFil: Eyzaguirre, L.. Henry M. Jackson Foundation; Estados UnidosFil: Montano, S. M.. U.S. Naval Medical Research Center Detachment; PerúFil: Laguna Torres, V.. U.S. Naval Medical Research Center Detachment; PerúFil: Serra, M.. National AIDS Control Program; UruguayFil: Aguayo, N.. National AIDS Control Program; ParaguayFil: Avila, Maria Mercedes. National Reference for AIDS; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Ruchansky, D.. National Laboratory of Reference for HIV-AIDS; UruguayFil: Pando, María de los Ángeles. National Reference for AIDS; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Vinoles, Jose. National Laboratory of Reference for HIV-AIDS; UruguayFil: Perez, J.. U.S. Naval Medical Research Center Detachment; PerúFil: Barboza, A.. National AIDS Control Program; ParaguayFil: Chauca, G.. U.S. Naval Medical Research Center Detachment; PerúFil: Romero, A.. U.S. Naval Medical Research Center Detachment; PerúFil: Galeano, A.. Tropical Medicine Institute; ParaguayFil: Blair, P.J.. U.S. Naval Medical Research Center Detachment; PerúFil: Weissenbacher, Mercedes Crecencia. National Reference for AIDS; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Birx, D. L.. Walter Reed Army Institute of Research; Estados UnidosFil: Sanchez, J. L.. Walter Reed Army Institute of Research; Estados UnidosFil: Olson, J. G.. U.S. Naval Medical Research Center Detachment; PerúFil: Carr, J. K.. Henry M. Jackson Foundation; Estados Unido

Rapid Low-Cost Microarray-Based Genotyping for Genetic Screening in Primary Immunodeficiency

Background: Genetic tests for primary immunodeficiency disorders (PIDs) are expensive, time-consuming, and not easily accessible in developing countries. Therefore, we studied the feasibility of a customized single nucleotide variant (SNV) microarray that we developed to detect disease-causing variants and copy number variation (CNV) in patients with PIDs for only 40 Euros. Methods: Probes were custom-designed to genotype 9,415 variants of 277 PID-related genes, and were added to the genome-wide Illumina Global Screening Array (GSA). Data analysis of GSA was performed using Illumina GenomeStudio 2.0, Biodiscovery Nexus 10.0, and R-3.4.4 software. Validation of genotype calling was performed by comparing the GSA with whole-genome sequencing (WGS) data of 56 non-PID controls. DNA samples of 95 clinically diagnosed PID patients, of which 60 patients (63%) had a genetically established diagnosis (by Next-Generation Sequencing (NGS) PID panels or Sanger sequencing), w