18 research outputs found

    An attempt to evaluate dynamics of water release from soil using photoacoustic spectroscopy

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    W prezentowanej pracy próbowaliśmy zastosować spektroskopię fotoakustyczną do oceny szybkości parowania (ewaporacji) gleby. W pomiarach wykorzystaliśmy aparaturę z dwoma wiązkami światła. Jedna z wiązek oświetlała próbki gleby silnym strumieniem światła niemodulowanego a druga z wiązek, o natężeniu ponad stukrotnie mniejszym, monitorowała zmiany zachodzące w badanych próbkach. Otrzymane rezultaty wskazują na możliwość wykorzystania spektroskopii fotoakustycznej nie tylko do oceny prędkości parowania gleby, lecz również w pomiarach zmian parametrów cieplnych jej wierzchnich warstw.In presented paper we have attempted to use photoacoustic spectroscopy to assess soil evaporation rate. We used equipment with two light beams in the measurements. One of the beams was illuminating soil samples with strong stream of non-modulated light and the second beam, with over one hundred times lower intensity, was monitoring changes proceeding in the tested samples. Obtained results indicate possibility to use photoacoustic spectroscopy not only for assessing soil evaporation rate, but also for measurements of changes in thermal parameters of its top layers

    Wstępna analiza możliwości zastosowania spektroskopii fotoakustycznej w fotofizyce gleby

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    In the present paper, an attempt was made to apply phothoacoustic spectroscopy (PAS) i.e., the particular version of photothermal spectroscopy where a quantity of energy deactivated into heat is evaluated, to quantify photophysical processes in a soil sample. As light sources three diodes emitting at blue, green and red bands of visible light spectrum were used. The obtained dependences of photoacoustic signal amplitude versus light modulation frequency did not follow predictions of Rosencwaig-Gersho classic theory since an additional heat exchange mechanism characteristic of powdered solid samples was likely to occur. In visible light spectrum band, two independent transition processes, achievable to our apparatus, were distinguished. The principal parameters: the relative photoacoustic signal amplitude and characteristic times (1.28 and 0.64 ms) of each revealed process were obtained.W niniejszej pracy podjęto próbę zastosowania spektroskopii fotoakustycznej (PAS), t.j. szczególnej wersji spektroskopii fototermalnej, w której ocenia się ilość energii dezaktywowanej do postaci ciepła, dla ilościowej oceny procesów fotofizycznych zachodzących w próbce glebowej. Jako źródło światła zastosowano trzy diody emitujące w pasmach niebieskim, zielonym i czerwonym widma światła widzialnego. Uzyskane zależności amplitudy sygnału fotoakustycznego od częstotliwości modulacji światła nie były zgodne z przewidywaniami klasycznej teorii Rosencwaiga-Gersho, co mogło być spowodowane wystąpieniem dodatkowego mechanizmu wymiany ciepła, charakterystycznego dla sproszkowanych próbek glebowych. W paśmie widma światła widzialnego wyróżniono dwa niezależne procesy przejściowe, wykrywalne dla naszej aparatury. Otrzymano podstawowe parametry: względną amplitudę sygnału foto-akustycznego oraz czasy charakterystyczne (1,28 oraz 0,64 ms) dla każdego z tych wykrytych procesów

    Reaction classes and agronomic categories of soils and their photoacoustic images

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    W prezentowanej pracy wykorzystaliśmy spektroskopię fotoakustyczną do oceny możliwości rozróżnienia, przy jej pomocy, gleb należących do różnych klas odczynu. Do pomiarów zestawiliśmy klasyczny spektrometr fotoakustyczny z wysokociśnieniową lampą ksenonową jako źródłem światła, oraz zamkniętą komorą pomiarową. Otrzymane rezultaty wskazują na możliwość wykorzystania spektroskopii fotoakustycznej zarówno do badania składu chemicznego gleby, jak i przynależności do określonej kategorii agronomicznej.In this work, we used photoacoustic spectroscopy for evaluation of the possibility of distinguishing between soils belonging to different reaction classes by means of this technology. For our measurements we used a classic photoacoustic spectrometer together with a high-pressure xenon lamp as a light source and a closed measuring chamber. The received results indicate the possibility of use of photoacoustic spectroscopy for examining the chemical constitution of soil as well as its affinity to a certain agronomical category

    Reproductive characteristics of northern pike, Esox lucius (Actinopterygii: Esociformes: Esocidae), in the Anzali Wetland, southwest Caspian Sea

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    Background. Temporal variability in fish reproductive features is influenced by environmental and spatial variations. Given the wide distribution of northern pike, Esox lucius Linnaeus, 1758, in the northern hemisphere, important reproductive features such as the initiation of the spawning activity are likely to vary with latitudinal gradients. The overall goal of the presently reported study was to answer basic questions regarding the reproductive biology of the pike and to discuss changes in the timing of the onset of spawning activity in relation to geographical locations and the water temperature in the Anzali Wetland compared to higher latitudes. Materials and methods. Monthly samples (537 specimens in total) were collected from the Anzali Wetland (southwest of the Caspian Sea) from July 2012 through July 2013. Samples were macro- and microscopically examined, and their maturity stages were identified, so that spawning season, monthly distribution of maturity stages, oocytes development, spawning strategy, length at 50% maturity, and fecundity were estimated. Results. The gonadosomatic index, oocyte size-frequency distribution, and histological examination suggested a relatively short spawning season, from February through March. The short annual spawning period and the oocyte size-frequency distribution demonstrated that pike is a total spawner with group synchronous oocyte development. The length at 50% maturity was 28.5 and 33.9 cm FL for males and females, respectively. Absolute fecundity values ranged from 4423 to 48471 oocytes, with mean (± standard error) of 16481 ± 2705 oocytes and the relative fecundity was estimated as 26.9 ± 1.6 oocytes per gram of mature female. Conclusion. The most important findings of this study are: the earlier initiation and relatively shorter duration of the reproductive activities of pike in the south Caspian region compared to northern geographical regions. The results emphasize the need for specific management strategies based on seasonal measures for pike such as: fish size limits, limitation of catches during the spawning season, limitation of the boat number, and closure of the spawning area during spawning months

    Reproductive characteristics of northern pike, Esox lucius (Actinopterygii: Esociformes: Esocidae), in the Anzali Wetland, southwest Caspian Sea

    No full text
    Background. Temporal variability in fish reproductive features is influenced by environmental and spatial variations. Given the wide distribution of northern pike, Esox lucius Linnaeus, 1758, in the northern hemisphere, important reproductive features such as the initiation of the spawning activity are likely to vary with latitudinal gradients. The overall goal of the presently reported study was to answer basic questions regarding the reproductive biology of the pike and to discuss changes in the timing of the onset of spawning activity in relation to geographical locations and the water temperature in the Anzali Wetland compared to higher latitudes. Materials and methods. Monthly samples (537 specimens in total) were collected from the Anzali Wetland (southwest of the Caspian Sea) from July 2012 through July 2013. Samples were macro- and microscopically examined, and their maturity stages were identified, so that spawning season, monthly distribution of maturity stages, oocytes development, spawning strategy, length at 50% maturity, and fecundity were estimated. Results. The gonadosomatic index, oocyte size-frequency distribution, and histological examination suggested a relatively short spawning season, from February through March. The short annual spawning period and the oocyte size-frequency distribution demonstrated that pike is a total spawner with group synchronous oocyte development. The length at 50% maturity was 28.5 and 33.9 cm FL for males and females, respectively. Absolute fecundity values ranged from 4423 to 48471 oocytes, with mean (± standard error) of 16481 ± 2705 oocytes and the relative fecundity was estimated as 26.9 ± 1.6 oocytes per gram of mature female. Conclusion. The most important findings of this study are: the earlier initiation and relatively shorter duration of the reproductive activities of pike in the south Caspian region compared to northern geographical regions. The results emphasize the need for specific management strategies based on seasonal measures for pike such as: fish size limits, limitation of catches during the spawning season, limitation of the boat number, and closure of the spawning area during spawning months

    Comparison of chromosome breakage in non-mosaic and mosaic patients with Fanconi anemia, relatives, and patients with other inherited bone marrow failure syndromes

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    BACKGROUND/AIMS: Fanconi anemia (FA) is a rare inherited bone marrow failure syndrome (IBMFS). Affected individuals must be distinguished from relatives, patients with mosaicism must be identified, and patients with other IBMFS classified as non-FA. The diagnostic feature of FA is increased chromosomal breakage in blood lymphocytes cultured with diepoxybutane or mitomycin C. METHODS: We sought a method to uniquely identify patients with FA with mosaicism, using cells from participants in the National Cancer Institute IBMFS cohort. Lymphocytes were treated with diepoxybutane or mitomycin C, and metaphases scored for breaks and radials. Analyses included the percentage of cells with any aberration, breaks per cell, and breaks per aberrant cell. RESULTS: There were 26 patients with FA (four mosaics), 46 FA relatives, and 62 patients with a non-FA IBMFS. By all analytic methods, patients with FA were abnormal compared with other groups. Those with FA mosaicism had more breakage than relatives or patients with non-FA IBMFS, but there was some individual overlap. CONCLUSIONS: The choices of clastogen are laboratory dependent, but there was not a method or analysis of lymphocytes that clearly distinguished all individuals mosaic for FA from relatives or patients with other IBMFS. Thus, genotyping remains the best method for providing absolute clarity

    Impact of Delta SARS-CoV-2 Infection on Glucose Metabolism: Insights on Host Metabolism and Virus Crosstalk in a Feline Model

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    Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) causes enhanced mortality in people with metabolic and cardiovascular diseases. Other highly infectious RNA viruses have demonstrated dependence on glucose transport and utilization, so we hypothesized that SARS-CoV-2 infection could lead to alterations in cellular and whole-body glucose metabolism. Twenty-four healthy domestic cats were intratracheally inoculated with B.1.617.2 (delta) SARS-CoV-2 and samples were collected at 4- and 12-days post-inoculation (dpi). Blood glucose and circulating cortisol concentrations were elevated at 4 and 12 dpi. Serum insulin concentration was statistically significantly decreased, while angiotensin 2 concentration was elevated at 12 dpi. SARS-CoV-2 RNA was detected in the pancreas and skeletal muscle at low levels; however, no change in the number of insulin-producing cells or proinflammatory cytokines was observed in the pancreas of infected cats through 12 dpi. SARS-CoV-2 infection statistically significantly increased GLUT protein expression in both the heart and lungs, correlating with increased AMPK expression. In brief, SARS-CoV-2 increased blood glucose concentration and cardio-pulmonary GLUT expression through an AMPK-dependent mechanism, without affecting the pancreas, suggesting that SARS-CoV-2 induces the reprogramming of host glucose metabolism. A better understanding of host cell metabolism and virus crosstalk could lead to the discovery of novel metabolic therapeutic targets for patients affected by COVID-19

    “Do-not-resuscitate” preferences of the general Swiss population: Results from a national survey

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    AIMS: To assess the do-not-resuscitate preferences of the general Swiss population and to identify predictors influencing decision-making. Methods: A nationwide web-based survey was conducted in Switzerland on a representative sample of the adult population. The primary endpoint was the preference for a “Do Not Resuscitate” order (DNR Code Status) vs. cardiopulmonary resuscitation (CPR Code Status) in a clinical case vignette of an out-of-hospital cardiac arrest. Secondary endpoint were participants’ own personal preferences for DNR. Results: 1138 subjects participated in the web-based survey, 1044 were included in the final analysis. Preference for DNR code status was found in 40.5% (n = 423) in the case vignette and in 20.3% (n = 209) when making a personal decision for themselves. Independent predictors for DNR Code Status for the case vignette were: Personal preferences for their own DNR Code Status (adjusted OR 2.44, 95%CI 1.67 to 3.55; p < 0.001), intubation following respiratory failure (adjusted OR 1.95, 95%CI 1.20 to 3.18; p = 0.007), time-period after which resuscitation should not be attempted (adjusted OR 0.91, 95%CI 0.89 to 0.93); p < 0.001), and estimated chance of survival in case of a cardiac arrest (adjusted OR per decile 0.91, 95%CI 0.84 to 0.99, p = 0.02; which was overestimated by all participants. Conclusions: Main predictors for a DNR Code Status were personal preferences and the overestimation of good neurological outcome after cardiac arrest. Overestimation of positive outcomes after cardiac arrest seems to influence patient opinion and should thus be addressed during code status discussions
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