Glacier mass balance models rely on accurate spatial calculation of input data, in particular air temperature. Lower temperatures (the so-called glacier cooling effect) and lower temperature ...variability (the so-called glacier damping effect) generally occur over glaciers compared to ambient conditions. These effects, which depend on the geometric characteristics of glaciers and display a high spatial and temporal variability, have been mostly investigated on medium to large glaciers so far, while observations on smaller ice bodies (< 0.5 km2) are scarce. Using a data set from eight on-glacier and four off-glacier weather stations, collected in the summers of 2010 and 2011, we analyzed the air temperature variability and wind regime over three different glaciers in the Ortles–Cevedale. The magnitude of the cooling effect and the occurrence of katabatic boundary layer (KBL) processes showed remarkable differences among the three ice bodies, suggesting the likely existence of important reinforcing mechanisms during glacier decay and fragmentation. The methods proposed by Greuell and Böhm (1998) and Shea and Moore (2010) for calculating on-glacier temperature from off-glacier data did not fully reproduce our observations. Among them, the more physically based procedure of Greuell and Böhm (1998) provided the best overall results where the KBL prevails, but it was not effective elsewhere (i.e., on smaller ice bodies and close to the glacier margins). The accuracy of air temperature estimations strongly impacted the results from a mass balance model which was applied to the three investigated glaciers. Most importantly, even small temperature deviations caused distortions in parameter calibration, thus compromising the model generalizability.
Cough: what's in a name? Widdicombe, J; Fontana, G
The European respiratory journal,
07/2006, Letnik:
28, Številka:
1
Journal Article
Recenzirano
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The cough reflex (CR) and the expiration reflex (ER) are two defensive reflexes from the respiratory tract, the latter mainly from the larynx. Both are elicited by mechanical and chemical irritation ...of the airway mucosa, and are a characteristic of airway diseases, but they have different functions. The CR first draws air into the lungs, to accentuate the subsequent expulsive phase; the ER consists of a strong expiration, to prevent aspiration of material into the lungs. They have different sensory pathways, central nervous circuits, and physiological and pharmacological modulations. In practice, coughing often consists of a combination of the two reflexes, a cough bout, epoch or attack. Articles on cough usually do not distinguish between the two reflexes, or whether the coughs are single events or epochs; they usually only measure frequency of expiratory efforts, and neglect other aspects. Current methods for measuring and assessing cough are described, with indications of when the use of these methods may be important.
A widespread loss of glacier area and volume has been observed in the European Alps since the 1980s. In addition to differences among various regions of the Alps, different responses to climate ...change characterize neighboring glaciers within the same region. In this study we describe the glacier changes in the Ortles-Cevedale group, the largest glacierized area in the Italian Alps. We analyze the spatial variability, the drivers, and the main factors controlling the current loss of ice in this region, by comparing mean elevation changes derived from two digital terrain models (DTMs), along with glacier extents and snow-covered areas derived from Landsat images acquired in 1987 and 2009, to various topographic factors. Glacier outlines were obtained using the band ratio method with manual corrections. Snow was classified from a near-infrared image after topographic correction. The total glacierized area shrank by 23.4 plus or minus 3% in this period, with no significant changes in the mean altitude of the glaciers. In 2009 the snowline was 240 m higher than in the 1960s and 1970s. From the snow-covered area at the end of summer 2009, which fairly represents the extent and local variability of the accumulation areas in the 2000s, we estimate that approximately 50% of the remaining glacier surfaces have to melt away to re-establish balanced mass budgets with present climatic conditions. The average geodetic mass budget rate, calculated for 112 ice bodies by differencing two DTMs, ranged from -0.18 plus or minus 0.04 to -1.43 plus or minus 0.09 m w.e. a super(-1), averaging -0.69 plus or minus 0.12 m w.e. a super(-1). The correlation analysis of mass budgets vs. topographic variables emphasized the important role of hypsometry in controlling the area and volume loss of larger glaciers, whereas a higher variability characterizes smaller glaciers, which is likely due to the higher importance of local topo-climatic conditions.
In this work we tested the suitability of thermistor strings as automatic tools for the continuous measurement of glacier ice ablation. Experimental data collected in summer 2017 over an Italian ...glacier provided ice ablation readings with accuracy similar to manual measurements with ablation stakes and other automatic systems, like the draw-wire method and the Bøggild ablatometer. Thermistor strings have potential for future applications in remote glacier monitoring, thanks to their flexibility, simple construction, and robustness.
The thermophysical properties, e.g., melting range, specific heat, solid fraction, density, and surface tension of four industrial Ni-based alloys, namely MC-2, CMSX-10, TMS-75, and LEK-94, have been ...determined within the ground-based experiments program of the ESA MAP ThermoProp project. The tests were performed under reducing atmosphere in order to lower the oxygen contamination. The results obtained have been compared with the corresponding data of Ni-based alloys available in literature. The new experimental data have been analyzed as a function of both temperature and alloy composition and interpreted by means of different thermodynamic models.
•An index of knock intensity has been based on the cylinder pressure oscillations.•This index allows to set the knock limited spark at different engine operating points.•The influence of the ...transducer position on the measurement of the pressure oscillations is investigated.
In this paper, knock intensity is deeply studied through experimental tests carried out on a turbo-charged spark-ignition engine. The experimental methodology is based on the analysis of the pressure signals detected within the engine combustion chamber.
In order to evaluate knock intensity, fast Fourier transform (FFT) and bandpass filtering techniques have been used to process the cylinder pressure values acquired in five hundred consecutive cycles. Resonance frequencies have been found at about 8.0kHz, 13.5kHz and 18.5kHz.
The maximum amplitude of pressure oscillations (MAPO) has been calculated for every engine cycle. In order to discriminate between knocking cycles and free knock cycles, MAPO values are compared to threshold values. These values have been determined following a statistical approach described in the paper.
An index of knock intensity, that takes into account both the extent of knocking events and the cycle- to-cycle variation has been introduced. Thus, at different engine operating points, the knock limited spark advance can be found.
At the end, a numerical analysis of the combustion process has been carried out in order to find a relationship between the knock occurrence and the combustion chamber geometry. A 3-D computational model, based on AVL FIRE v2011 code, has been utilized. The 3-D model is able to predict the auto-ignition zones. By matching these zones and the map of mixture distribution, it is possible to predict the location of the most dangerous areas within the combustion chamber. Furthermore, comparisons of calculated and measured data provide sound information about the importance of pressure transducer position in terms of knock intensity quantifying.
The continuation of valuable, long-term glacier observation series is threatened by the accelerated mass loss which currently affects a large portion of so-called "benchmark" glaciers. In this work ...we present the evolution of the Careser Glacier, from the beginning of systematic observation at the end of the 19th century to its current condition in 2012. In addition to having one of the longest and richest observation records among the Italian glaciers, Careser is unique in the Italian Alps for its 46 yr mass balance series that started in 1967. In the present study, variations in the length, area and volume of the glacier since 1897 are examined, updating and validating the series of direct mass balance observations and adding to the mass balance record into the past using the geodetic method. The glacier is currently strongly out of balance and in rapid decay; its average mass loss rate over the last 3 decades was 1.5 m water equivalent per year, increasing to 2.0 m water equivalent per year in the last decade. Although these rates are not representative at a regional scale, year-to-year variations in mass balance show an unexpected increase in correlation with other glaciers in the Alps, during the last 3 decades. If mass loss continues at this pace, the glacier will disappear within a few decades, putting an end to this unique observation series.
Safe access to public restrooms is an essential need for participation in civic life, in the workplace, in educational settings, and other public spaces. This is no different for transgender people. ...However, access to public restrooms according to gender identity has sparked controversy to the extent that transgender people face embarrassment and even expulsion from these spaces. The lack of access of the transgender population to public restrooms has a negative impact on the physical and mental health of this population. Thus, this article aims to address the main consequences that the ban on the use of bathrooms has for the transgender population, specifically the access of transgender women to the women's restroom. We covered some legal aspects of "bathroom laws" and the main arguments in this discussion. We understand that the prohibition of access to the restroom constitutes a form of gender violence and discrimination, as we conclude that the arguments that express concerns about safety are not supported.
This paper examines the ability of LiDAR topography to provide reach-scale width values for the analysis of downstream hydraulic geometry relationships along some streams in the Dolomites (northern ...Italy). Multiple reach-scale dimensions can provide representative geometries and statistics characterising the longitudinal variability in the channel, improving the understanding of geomorphic processes across networks. Starting from the minimum curvature derived from a LiDAR DTM, the proposed algorithm uses a statistical approach for the identification of the scale of analysis, and for the automatic characterisation of reach-scale bankfull widths. The downstream adjustment in channel morphology is then related to flow parameters (drainage area and stream power). With the correct planning of a LiDAR survey, uncertainties in the procedure are principally due to the resolution of the DTM. The outputs are in general comparable in quality to field survey measurements, and the procedure allows the quick comparison among different watersheds. The proposed automatic approach could improve knowledge about river systems with highly variable widths, and about systems in areas covered by vegetation or inaccessible to field surveys. With proven effectiveness, this research could offer an interesting starting point for the analysis of differences between watersheds, and to improve knowledge about downstream channel adjustment in relation, for example, to scale and landscape forcing (e.g. sediment transport, tectonics, lithology, climate, geomorphology, and anthropic pressure).
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