Abstract. New particle formation and growth has a very important role in many climate processes. However, the overall knowlegde of the chemical composition of atmospheric nucleation mode (particle diameter, d<20 nm) and the lower end of Aitken mode particles (d≤50 nm) is still insufficient. In this work, we have applied the UFO-TDMA (ultrafine organic tandem differential mobility analyzer) method to shed light on the presence of an organic fraction in the nucleation mode size class in different atmospheric environments. The basic principle of the organic fraction detection is based on our laboratory UFO-TDMA measurements with organic and inorganic compounds. Our laboratory measurements indicate that the usefulness of the UFO-TDMA in the field experiments would arise especially from the fact that atmospherically the most relevant inorganic compounds do not grow in subsaturated ethanol vapor, when particle size is 10 nm in diameter and saturation ratio is about 86% or below it. Furthermore, internally mixed particles composed of ammonium bisulfate and sulfuric acid with sulfuric acid mass fraction ≤33% show no growth at 85% saturation ratio. In contrast, 10 nm particles composed of various oxidized organic compounds of atmospheric relevance are able to grow in those conditions. These discoveries indicate that it is possible to detect the presence of organics in atmospheric nucleation mode sized particles using the UFO-TDMA method. In the future, the UFO-TDMA is expected to be an important aid to describe the composition of atmospheric newly-formed particles.
Early reports of male immunological infertility suggested a decline in antisperm antibody concentrations in some patients after even short-term (10 day) therapy with low-dose prednisolone. In the present study, 53 men with positive results in spermatozoal mixed antiglobulin reaction (MAR) and serum tray agglutination tests (TAT), were randomized to receive either 20 mg of prednisolone or placebo daily for 2 weeks prior to in-vitro fertilization (IVF) treatment. The antibody levels were also monitored by flow cytometry (FCM). There were no significant differences between these groups as regards fertilization rates (35% with prednisolone; 39% with placebo) and pregnancy rates (29%; 32%). No significant changes occurred in either MAR or FCM results in relation to therapy. Patients with fertilization rates of < 10% had significantly higher immunoglobulin G (IgG) MAR values compared with those with better fertilization, whereas there was no relationship between IgA levels and fertilization results. As regards FCM, the results were similar, but without statistical significance. In conclusion, IVF is a good course of action in severe male immune infertility, but low-dose prednisolone therapy does not lower the sperm-bound antibody numbers and does not improve the IVF outcome.
Background: Altered adrenocortical activity is one suggested mechanism relating small birth size with the metabolic syndrome in adulthood. Adrenal androgen concentrations are higher in children born small (SGA) than appropriate for gestational age (AGA). Aim: To compare adrenocortical hormonal activity between 20-year-old subjects born SGA or AGA. Methods: Seventy 20-year-old subjects (35 SGA and 35 age- and gender-matched AGA controls) were studied. Serum cortisol, cortisone, corticosteroid-binding globulin (CBG), glucocorticoid bioactivity (GBA), aldosterone, dehydroepiandrosterone sulfate (DHEAS) and androstenedione were measured, and the free cortisol index (FCI) was calculated. Results: The mean levels of glucocorticoid parameters, aldosterone, DHEAS or androstenedione did not differ between the SGA and AGA groups. In both groups, the males had lower cortisol (p < 0.05) and CBG levels (p < 0.01) and higher DHEAS (p < 0.01) concentrations than the females. Females who used hormonal contraceptives had higher cortisol and CBG levels (p < 0.01) but similar FCI, GBA and DHEAS levels than females who did not use contraceptives. Conclusion: No differences in adrenocortical activity were found between 20-year-old SGA and AGA subjects. Enhanced peripubertal adrenal androgen secretion seems to disappear by early adulthood in full-term born SGA subjects. FCI and GBA are useful parameters in the evaluation of the glucocorticoid milieu during hormonal contraceptive use.
Research Highlights: This study offers new information on the cross cutting of decayed stems with the sounding of short (0.5 m) offcuts and the bucking of longer (3.0 m) butt-rotten poles. Background and Objectives: The root and butt-rot fungus Heterobasidion annosum sensu lato (Fr.) Bref. causes wood quality damage to trees in softwood forests. When timber is harvested in butt-rotten forests, it is essential that the decayed part of the tree is recognized and cut away from a stem, while the healthy and good quality log section of a stem is cross cut with precision sawlogs. The objective of the study was to investigate the impact of two off-cutting methods on stem processing time, cutting productivity, sawlog volume, and commercial value at the roadside landing when harvesting timber from the butt-rotten Norway spruce (Picea abies (L.) Karst.) final-felling forests. Materials and Methods: The length of the short offcuts used was 0.5 m. The results of the cross-cutting practices were compared to the decayed pulpwood poles of 3 m from the butt of the rotten stems. Time and motion studies were carried out in stands before the profitability calculations. The study data consisted of 1980 Norway spruce sawlog stems. Results: Sounding of the short offcuts added significantly to the stem processing time of butt-rotten stems, but the sawlog volume and the timber value recovery of the stems were higher than those of the decayed pulpwood poles of 3 m. Conclusions: The study concluded that sounding of butt-rotten Norway spruce stems with one to three offcuts is economically profitable if the diameter of the decayed column at the stem stump’s height is small (≤5 cm). In contrast, when the width of the decay is larger (>5 cm), it is more profitable to first cross cut the decayed pulpwood pole of 3 m and then to observe the height of the decayed part of the stem.
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