CCN activation experiments with adipic acid: effect of particle phase and adipic acid coatings on soluble and insoluble particles

Slightly soluble atmospherically relevant organic compounds may influence particle CCN activity and therefore cloud formation. Adipic acid is a frequently employed surrogate for such slightly soluble organic materials. The 11 published experimental studies on the CCN activity of adipic acid particles are not consistent with each other nor do they, in most cases, agree with the Köhler theory. The CCN activity of adipic acid aerosol particles was studied over a significantly wider range of conditions than in any previous single study. The work spans the conditions of the previous studies and also provides alternate methods for producing "wet" (deliquesced solution droplets) and dry adipic acid particles without the need to produce them by atomization of aqueous solutions. The experiments suggest that the scatter in the previously published CCN measurements is most likely due to the difficulty of producing uncontaminated adipic acid particles by atomization of solutions and possibly also due to uncertainties in the calibration of the instruments. The CCN activation of the small (<i>d</i><sub><i>m</i></sub><150 nm) initially dry particles is subject to a deliquescence barrier, while for the larger particles the activation follows the Köhler curve. Wet adipic acid particles follow the Köhler curve over the full range of particle diameters studied. In addition, the effect of adipic acid coatings on the CCN activity of both soluble and insoluble particles has also been studied. When a water-soluble core is coated by adipic acid, the CCN-hindering effect of particle phase is eliminated. An adipic acid coating on hydrophobic soot yields a CCN active particle. If the soot particle is relatively small (<i>d</i><sub>core</sub>≤102 nm), the CCN activity of the coated particles approaches the deliquescence line of adipic acid, suggesting that the total size of the particle determines CCN activation and the soot core acts as a scaffold

Emotional labor and professional practice in sports medicine and science

The aim of the present study was to explore how sport medicine and science practitioners manage their emotions through emotional labor when engaging in professional practice in elite sport. To address the research aim a semi-structured interview design was adopted. Specifically, eighteen professional sport medicine and science staff provided interviews. The sample comprised sport and exercise psychologists (n = 6), strength and conditioning coaches (n = 5), physiotherapists (n = 5), one sports doctor and one generic sport scientist. Following a process of thematic analysis, the results were organized into the following overarching themes: (a) factors influencing emotional labor enactment, (b) emotional labor enactment and, (c) professional and personal outcomes. The findings provide a novel contribution to understanding the professional demands faced by practitioners, and are discussed in relation to the development of professional competencies and the welfare and performance of sport medics and scientists

Better Preparing Sports Psychologists for the Demands of Applied Practice: The Emotional Labor Training Gap

The aim of this manuscript was to investigate the emotional educational-training-practice gap in the professional formation of sport and exercise psychologists in the United Kingdom through the theoretical lens of emotional labor. Twenty semi-structured interviews were conducted with four participant groups: master’s students (n = 5), trainee (n = 5), neophyte (n = 5) and experienced sport and exercise psychologists (n = 5). Adopting an interpretive epistemology, an abductive thematic analysis was conducted in relation to the participant groups recruited. Several overarching themes were identified in each participant group: (a) master’s students (emotional labor as theory, practice), (b) trainees (emotional labor to survive, a professional development tool), (c) neophytes (emotional labor as a new professional, self-care) and (d) experienced sport and exercise psychologists (emotional labor as a professional resource, lifelong learning). A synthesized list of applied recommendations to improve the professional formation of sport and exercise psychologists was developed based on the analysis. The themes extend sport and exercise psychology professional development literature and we make recommendations for educators, professional associations and regulatory bodies with regard to: (a) bridging the emotional labor and experiential gap when transitioning between development phases via collaborative and innovative educational provision; (b) supporting the development of skills relating to the enactment of emotional labor, and; (c) consider support mechanisms for student/trainee/neophyte safeguarding and welfare issues as a result of the emotion-laden transactions in professional practice. The implications for future pedagogy, andragogy and research are discussed

Acute graft versus host disease

Acute graft-versus-host disease (GVHD) occurs after allogeneic hematopoietic stem cell transplant and is a reaction of donor immune cells against host tissues. Activated donor T cells damage host epithelial cells after an inflammatory cascade that begins with the preparative regimen. About 35%–50% of hematopoietic stem cell transplant (HSCT) recipients will develop acute GVHD. The exact risk is dependent on the stem cell source, age of the patient, conditioning, and GVHD prophylaxis used. Given the number of transplants performed, we can expect about 5500 patients/year to develop acute GVHD. Patients can have involvement of three organs: skin (rash/dermatitis), liver (hepatitis/jaundice), and gastrointestinal tract (abdominal pain/diarrhea). One or more organs may be involved. GVHD is a clinical diagnosis that may be supported with appropriate biopsies. The reason to pursue a tissue biopsy is to help differentiate from other diagnoses which may mimic GVHD, such as viral infection (hepatitis, colitis) or drug reaction (causing skin rash). Acute GVHD is staged and graded (grade 0-IV) by the number and extent of organ involvement. Patients with grade III/IV acute GVHD tend to have a poor outcome. Generally the patient is treated by optimizing their immunosuppression and adding methylprednisolone. About 50% of patients will have a solid response to methylprednisolone. If patients progress after 3 days or are not improved after 7 days, they will get salvage (second-line) immunosuppressive therapy for which there is currently no standard-of-care. Well-organized clinical trials are imperative to better define second-line therapies for this disease. Additional management issues are attention to wound infections in skin GVHD and fluid/nutrition management in gastrointestinal GVHD. About 50% of patients with acute GVHD will eventually have manifestations of chronic GVHD

Aerosol quantification with the Aerodyne Aerosol Mass Spectrometer: detection limits and ionizer background effects

Systematic laboratory experiments were performed to investigate quantification of various species with two versions of the Aerodyne Aerosol Mass Spectrometer, a Quadrupole Aerosol Mass Spectrometer (Q-AMS) and a compact Time-of-Flight Aerosol Mass Spectrometer (c-ToF-AMS). Here we present a new method to continuously determine the detection limits of the AMS analyzers during regular measurements, yielding detection limit (<i>DL</i>) information under various measurement conditions. Minimum detection limits range from 0.03 μg m<sup>−3</sup> (nitrate, sulfate, and chloride) up to 0.5 μg m<sup>−3</sup> (organics) for the Q-AMS. Those of the c-ToF-AMS are found between 0.003 μg m<sup>−3</sup> (nitrate, sulfate) and 0.03 μg m<sup>−3</sup> (ammonium, organics). The <i>DL</i> values found for the c-ToF-AMS were ~10 times lower than those of the Q-AMS, mainly due to differences in ion duty cycle. Effects causing an increase of the detection limits include long-term instrument contamination, measurement of high aerosol mass concentrations and short-term instrument history. The self-cleaning processes which reduce the instrument background after measurement of large aerosol concentrations as well as the influences of increased instrument background on mass concentration measurements are discussed. Finally, improvement of detection limits by extension of averaging time intervals, selected or reduced ion monitoring, and variation of particle-to-background measurement ratio are investigated