Miracle-dz/UniFAR-FTUs huggingface dataset:
Distribution of Snow Drifts on Ridge Slopes: Measurements and Theoretical Approximations

During several winters the positions and magnitudes of excess snow deposits or denudation zones caused by wind have been evaluated on the flanks of regular, elongated mountain ridges. The surveys were carried out by conventional measurements of mass balance. According to angle of slope (10 to 35°), shape of crest (hump- or wedge-shaped) and orientation to the wind, various patterns of snow deposition may be found. It is shown that, on ridges oriented perpendicularly to the main wind direction (north-west) during snow storms, near-periodic snow deposits may be expected on the lee slope. On the windward side, there is a denudation zone near the crest. The measurements indicate that lee slopes, of mean slope angle, are buried in mid-winter under twice as much snow as the adjacent windward slopes. However, the ridge system as a whole accumulates the same amounts of snow as do areas of flat terrain. Theoretical approximations based on theories of potential flow and semi-empi rical plume models are used to simulate the presumed dispersion of snow. The model calculations, intended as diagnostic tools, suggest that snow may be diffused and deposited on lee slopes in a plume-like manner similar to other particulate matter. Snowfall, together with low-level blowing snow as an additional source of suspended particles, appears to increase the snow deposits, mainly on the foot of steeper ridges.
Exposure and bioavailability of Cerium through the ingestion of soil (Uganda)

The UK Department For International Development (DFID) Technical Development and Research (TDR) programme funded a three-year project between 1995 and 1998 entitled “Cerium & Endomyocardial Fibrosis in Tropical Terrains” (Project R6228). The presence of elevated levels of dietary Ce, and deficient levels of dietary Mg in southern India have been assigned as potential environmental cofactors in the aetiology of Endomyocardial Fibrosis, which is also endemic in certain areas of Uganda. One of the aims of the project is to assess the relative importance of various exposure scenarios for the Ugandan population to Ce to define protective measures if required. Initial assessments of dietary intakes of Ce in Ugandan soils and foodstuffs have indicated that soils are a significant exposure pathway. A review is presented of exposure to soil and its ingestion both world-wide and specifically in Uganda. The deliberate consumption of soil by pregnant women and children (during the crawling stage of their development and between the ages of 4 and 8) is common in Uganda. However, prior to this study no information was available concerning the bioavailability of Ce in ingested soil or soil contaminated food. A Physiologically Based Extraction Test (PBET) has been used to determine the bioaccessibility of Ce in soil and dust samples from two districts in Uganda. The PBET incorporates gastro-intestinal tract parameters representative of a human for predicting the bioaccessibility of metals from an ingested solid matrix . Results showed there was a large degree of variation in Ce bioaccessibility between the samples, and between the different size fractions of individual samples. There was a marked increase in bioaccessibility when the pH was increased between the stomach and small intestine phases of the PBET for the smaller size fractions between >20 and <1 μm. Variations in mineralogy are considered to have caused the variations in Ce bioacessibility, although it was not possible to accurately determine specific mineral phases due to the small size of the minerals in the finest soil fractions.
Enhancement of a Turbulence Sub-Model for More Accurate Predictions of Vertical Stratifications in 3D Coastal and Estuarine Modeling

This paper presents an improvement of the Mellor and Yamada's 2nd order turbulence model in the Princeton Ocean Model (POM) for better predictions of vertical stratifications of salinity in estuaries. The model was evaluated in the strongly stratified estuary, Apalachicola River, Florida, USA. The three-dimensional hydrodynamic model was applied to study the stratified flow and salinity intrusion in the estuary in response to tide, wind, and buoyancy forces. Model tests indicate that model predictions over estimate the stratification when using the default turbulent parameters. Analytic studies of density-induced and wind-induced flows indicate that accurate estimation of vertical eddy viscosity plays an important role in describing vertical profiles. Initial model revision experiments show that the traditional approach of modifying empirical constants in the turbulence model leads to numerical instability. In order to improve the performance of the turbulence model while maintaining numerical stability, a stratification factor was introduced to allow adjustment of the vertical turbulent eddy viscosity and diffusivity. Sensitivity studies indicate that the stratification factor, ranging from 1.0 to 1.2, does not cause numerical instability in Apalachicola River. Model simulations show that increasing the turbulent eddy viscosity by a stratification factor of 1.12 results in an optimal agreement between model predictions and observations in the case study presented in this study. Using the proposed stratification factor provides a useful way for coastal modelers to improve the turbulence model performance in predicting vertical turbulent mixing in stratified estuaries and coastal waters.
Equilibrium sensitivities of the Greenland ice sheet inferred from the adjoint of the three- dimensional thermo-mechanical model SICOPOLIS

We extend the application of control methods pioneered, in the context of ice stream models, by MacAyeal [1992, 1993] to the comprehensive three-dimensional thermo-mechanical ice sheet model SICOPOLIS. Lagrange multipliers (i.e. sensitivities) are computed with an exact, efficient adjoint model that has been generated from SICOPOLIS by rigorous application of automatic differentiation (AD). The case study uses the adjoint to determine the sensitivity of the total Greenland ice volume to various control variables over a 100-year period. The control space has on the order of 1.2 million elements, consisting of spatial fields of model parameters, surface and basal forcings, and initial conditions. Reliability of the adjoint was tested through finite-difference perturbation calculations for various control variables and perturbation regions, ascertaining quantitative “predictions” of the adjoint. Besides confirming qualitative aspects of ice sheet sensitivities, such as expected regional variations, we detect regions where model sensitivities are seemingly unexpected or counter-intuitive, albeit “real” in the sense of actual model behavior. Examples are positive basal sliding coefficient sensitivities as well as positive cold ice temperature sensitivities in certain parts of the ice sheet. The objective of this article is largely a proof of concept. Available adjoint code generation tools now open up a variety of novel model applications, notably with regard to sensitivity and uncertainty analyses and ice sheet state estimation or data assimilation.
Petrogenesis of Early Cretaceous silicic volcanism in SE Uruguay: The role of mantle and crustal sources

1Dipartimento di Scienze della Terra, Universita degli Studi di Roma La Sapienza, P.le A. Moro, 5, 00185 Roma, Italy 2Istituto di Geologia ambientale e Geoingegneria (IGAG, CNR), c/o Universita degli Studi di Roma La Sapienza, P.le A. Moro, 5, 00185 Roma, Italy 3Dipartimento di Scienze della Terra, Universita degli Studi di Napoli Federico II, via Mezzocannone, 8, 80134 Napoli, Italy 4Departamento de Mineralogia e Geotectonica, Universidade de Sao Paulo, Rua do Lago, 562, Cidade Universitaria, DEP 05508-900, Sao Paulo, Brazil
Influence of snow accumulation and snowmelt on streamflow in the central Spanish Pyrenees / Influence de l’accumulation et de la fonte de la neige sur les écoulements dans les Pyrénées centrales espagnoles

Abstract Abstract Results of studies related to the effect of snow accumulation and snowmelt on river regimes of the central Spanish Pyrenees are presented. Streamflow of the Pyrenean rivers is characterized by low and constant discharges during winter because of accumulation of snow in the basins above 1600 m a.s. l. , and high and fluctuating discharges during spring due to snowmelt and rainfall. Regional discharge contrasts have been assessed in relation to the Atlantic influence and the percentage of high altitude areas in each basin. In most of the Pyrenean basins, snowmelt contributes more to the discharge than rainfall in the spring. The analysis of data shows a decrease in winter precipitation in the last 50 years causing a decrease in both winter and spring discharges and introducing changes in the distribution of streamflow throughout the year.
Reservoir monitoring of steam‐assisted gravity drainage using borehole measurements

This paper presents the results from a research project focusing on permanent cross‐well geophysical methods for reservoir monitoring during steam‐assisted gravity drainage. A feasibility study indicated detectable differences in seismic and electrical reservoir properties based on expected changes in temperature and fluid saturation during the production of extra heavy oil. As a result of this, a permanent cross‐well system was installed at the Leismer Demonstration Area, located in the Athabasca Oil Sands region in Alberta, Canada. Baseline data sets, including cross‐well seismic, three‐dimensional vertical seismic profiling and cross‐well electrical resistivity tomography, have been acquired. Comparisons between conventional surface seismic and downhole seismic data show an increase in resolution and frequency content as expected. Steam‐assisted gravity drainage‐induced time‐lapse effects are clearly visible in the 3D vertical seismic profiling and electrical resistivity tomography data sets, even after a few months of oil production. In general, the 3D vertical seismic profiling images show a higher resolution than the surface seismic data, in particular when dealing with vertical positioning of the time‐lapse events. The electrical resistivity tomography baseline shows clear separation between zones of high and low electrical resistivity, and during 23 months of electrical resistivity tomography measurements the maximum reduction of resistivity is 85%. Time‐lapse observations from acoustic and electrical borehole data correspond well, and are also supported by temperature measurements in the two observation wells. Emerging technologies, updated models, improved flexibility, and reduced costs will allow future reservoir monitoring with surface and borehole data in combination, or even with borehole data exclusively.
When predator becomes prey

Credit: Greenpeace. Photo by Jeremy Sutton-Hibbert. Conservation groups such as the Australian Marine Conservation Society (AMCS) and its patron, well-known writer Tim Winton, are campaigning to save Australia’s sharks. Already, they have successfully lobbied to reduce shark quotas in Queensland. According to the Society, 100 million sharks are killed each year around the world, and shark numbers have declined by 90 per cent. As a top predator, sharks are known as a keystone species. They maintain the balance of prey species, which sets up a cascading effect across the entire marine food web. For this reason, reducing the numbers of sharks has significant and unpredictable impacts on marine ecosystems.
Środowiskowe aspekty planowanej reformy Wspólnej Polityki Rolnej

Celem artykułu jest identyfikacja potencjalnych kierunków zmian oddziaływania rolnictwa na środowisko w różnych wariantach reform wspólnej polityki rolnej (WPR). Na podstawie analizy wpływu potencjalnych zmian WPR na rozwój europejskiego rolnictwa w perspektywie do 2020 r. , przedstawiono prawdopodobne konsekwencje planowanej reformy tej polityki w wymiarze środowiskowym. Uwzględniając dwie najważniejsze propozycje reformy, stwierdzono, że żadna z nich nie prowadzi do znaczącej liberalizacji polityki rolnej, co jest korzystne w świetle zrównoważonego rozwoju. Porównanie projektów przedstawionych przez Komisję Europejską i Parlament Europejski pozwala stwierdzić, że wdrożenie pierwszego z nich prowadziłoby do ekologizacji rolnictwa w szerszym zakresie. W propozycji Parlamentu nie przewiduje się daleko idących zmian, co oznacza, że w tym wariancie instrumenty ochrony środowiska byłyby skutecznie wdrażane, ale jedynie na części użytków rolnych. Równolegle duża część obszarów wykorzystywanych rolniczo podlegałaby dalszej intensyfikacji, więc zmiany WPR sprzyjałyby dwukierunkowemu rozwojowi rolnictwa i obszarów wiejskich.
Hysteresis-based switching algorithms for supervisory control of uncertain systems - eScholarship

We address the problem of controlling a linear system with unknown parameters ranging over a continuum by means of switching among a finite family of candidate controllers. We present a new hysteresis-based switching logic, designed specifically for this purpose, and derive a bound on the number of switches produced by this logic on an arbitrary time interval. The resulting switching control algorithm is shown to provide stability and robustness to arbitrary bounded noise and disturbances and sufficiently small unmodeled dynamics. (C) 2002 Elsevier Science Ltd. All rights reserved.
Morphostructure and magnetic fabric of the northwestern North Fiji Basin

Four successive spreading phases are distinguished in the northwestern part of the North Fiji Basin. After an initial NE-SW opening, a N-S spreading phase took place, up to the northwesternmost tip of the basin, along the South Pandora, Tikopia and 9°30 Ridges. The N-S spreading phase in the northern North Fiji Basin was followed by an E-W opening phase along the central North Fiji Basin axis. A triple junction was probably active during an intermediate stage between the two phases. E-W spreading underwent a reorganisation that induced the functioning of the 16°40′S triple junction and the development of the E-W trending Hazel Holme Extensional Zone from the active central spreading axis to the southern tip of the New Hebrides Back-Arc Troughs. Active extension also occurs along the E-W Santa Cruz Trough which crosscuts the arc platform at the northern end of the N-S trending Back-Arc Troughs. The existence of the Back-Arc Troughs is mainly due to the construction of the 400 km-long volcanic Duff Ridge which trapped a piece of the old North Fiji Basin oceanic crust.
Motile Properties of the Kinesin-related Cin8p Spindle Motor Extracted from Saccharomyces cerevisiae Cells*

We have developed microtubule binding and motility assays for Cin8p, a kinesin-related mitotic spindle motor protein from Saccharomyces cerevisiae. The methods examine Cin8p rapidly purified from crude yeast cell extracts. We created a recombinant form of CIN8 that fused the biotin carrying polypeptide from yeast pyruvate carboxylase to the carboxyl terminus of Cin8p. This form was biotinated in yeast cells and provided Cin8p activity in vivo. Avidin-coated glass surfaces were used to specifically bind biotinated Cin8p from crude extracts. Microtubules bound to the Cin8p-coated surfaces and moved at 3.4 ± 0.5 μm/min in the presence of ATP. Force production by Cin8p was directed toward the plus ends of microtubules. A mutation affecting the microtubule-binding site within the motor domain (cin8-F467A) decreased Cin8p’s ability to bind microtubules to the glass surface by >10-fold, but reduced gliding velocity by only 35%. The cin8–3 mutant form, affecting the α2 helix of the motor domain, caused a moderate defect in microtubule binding, but motility was severely affected.cin8-F467A cells, but not cin8–3 cells, were greatly impaired in bipolar spindle forming ability. We conclude that microtubule binding by Cin8p is more important than motility for proper spindle formation.
Laser-induced fluorescence signatures as a tool for remote monitoring of water and nitrogen stresses in plants

We tested the potential of leaf fluorescence as a tool for the remote sensing of water and nitrogen stresses in agricultural crops, as compared to the conventional contact techniques of leaf tissue or soil analysis. Multi-wavelength excitation fluorescence and diurnal behavior of the variable chlorophyll fluorescence were used to monitor nitrogen deficiency in corn (GEOIDE RES#54 network project, Canada) and water stress in pea plants (LURE project, France). Variable chlorophyll fluorescence was found to be a very sensitive tool, giving early indications of the drought stress and general indications of a misfunction of the photosynthetic apparatus. Some fluorescence parameters derived from ultraviolet (UV) and visible light (VIS) excitation of chlorophyll, especially the ratio FRFexUV/FRFexVIS measuring the epidermis UV transmittance, seemed to be more specifically related to the nitrogen content of leaves and precluded an ambiguous response as in the case of the more complex ratio BGF/ChlF. Despite the high variability of the biological material in the field, fluorescence could discriminate between N-deficient and N-saturated plants, and between water-stressed and non-water-stressed plants in the early stages of stress development.
Dynamics of altitudinal tree-limits in Sweden: a review

The dynamic nature of Swedish (and Scandinavian) alpine tree-limits is reviewed in the perspective of recent research covering four timescales, viz. (1) the long-term Holocene perspective, (2) the Little Ice Age, (3) the post-Little Ice Age warming, and (4) the recent cooling. On all scales the tree-limits indicate a sensitive response in accordance with the tree-limit history and temperature trends (particularly seasonality) postulated for a wider geographical spectrum of the northern hemisphere. In detail, species have responded individualistically, particularly stressing the regenerative strategies. Vegetative regeneration and phenotypic plasticity provide relative stability to the altitudinal range limits of mountain birch, spruce and rowan, in contrast to the pine.
Trench‐normal variation in observed seafloor displacements associated with the 2011 Tohoku‐Oki earthquake

Seafloor geodetic measurements using the GPS/acoustic technique just above the rupture area of the 2011 Tohoku‐Oki earthquake revealed strong trench‐normal variation in the horizontal crustal displacement associated with the earthquake. One set of observations, at a site only 50 km away from the trench, yielded the most trench‐ward data ever reported with an accuracy better than 1 m. It showed a coseismic displacement of up to 31 m, whereas another set of observations 100 km away from the trench showed a 15‐m displacement. These horizontal data, as well as vertical data from pressure gauges and tsunami observations, strongly indicate that the seismic slip reached the trench. They are also likely to contribute quantitatively to further investigations that reveal the coseismic behavior of the frontal wedge of the overriding plate in the source region along the Japan Trench.
North Atlantic deep water circulation collapse during Heinrich events

Paleoceanographic proxy data and ocean general circulation models have been combined to investigate the response of the North Atlantic Ocean to Heinrich-type meltwater episodes. Because of the uncertainties over the origin of the Heinrich events, three different scenarios have been modeled: (1) a Heinrich event caused by a dramatic increase in the iceberg discharge from the Laurentide ice sheet or Labrador ice shelf, (2) a Heinrich event driven by enhanced iceberg discharge from the Barents shelf, which was transported into the northern North Atlantic, and (3) a meltwater episode that was confined to the Nordic Seas. The ocean regional and global circulation models cannot distinguish between the Laurentide and Barents shelf Heinrich event scenarios because both led to a complete cessation of the deep-water thermohaline conveyor belt. The meltwater episode confined to the Nordic Seas only weakened the overturning and may represent circulation changes that may occur during the Dansgaard-Oeschger events.
The Palaeoproterozoic Trans-Hudson Orogen: a prototype of modern accretionary processes

Abstract The Trans-Hudson Orogen (THO) of North America is one of the earliest orogens in Earth's history that evolved through a complete Wilson Cycle. It represents c. 150 Ma of opening of the Manikewan Ocean, from c. 2.07–1.92 Ga, followed by its demise in the interval 1.92–1.80 Ga, during the final phase of growth of the Supercontinent Columbia (Nuna). It is characterized by three lithotectonic divisions: (i) Churchill margin (or peri-Churchill); (ii) Reindeer Zone; and (iii) Superior margin (or peri-Superior). The peri-Churchill realm records progressive outward continental growth by accretion of Archaean to Palaeoproterozoic micro-continents (Hearne, Meta Incognita/Core Zone, Sugluk) and eventually arc terranes (La Ronge–Lynn Lake) to the Slave-Rae nuclei, with attendant development of orogenies and basin inversions related to the specific accretion events (1.92–1.89 Ga Snowbird; 1.88–1.865 Ga Foxe; 1.87–1.865 Ga Reindeer orogenies). The Reindeer Zone is characterized by primitive to evolved oceanic arcs, back-arc basins, oceanic crust and ocean plateaus that formed during closure of the Manikewan Ocean, and accretion of a micro-continent (Sask Craton) and smaller Archaean crustal fragments. The terminal phase of the Trans–Hudson orogeny represents collision between the Superior craton, the Reindeer Zone and the composite western Churchill Province during the interval 1.83–1.80 Ga.
Building Degree Profiles. The Tuning Approach

The development of degree profiles is an important art which has become quite specialized in recent years. This article concentrates on the analysis of the importance of the role of degree profiles in the design of degrees and, as a consequence, in Higher Education in general. It analyses, particularly, the work of the Tuning Project and its main processes in relation to profile building. It also gathers together and systematizes the specific contribution of four main components which should be taken into consideration at the time of the creation of new qualifications: two of the components relate to the analysis of social and professional needs and the future trends in the area. Both of these elements provide the relevance which a degree profile should strive to attain. The third component, the reference to the meta-profile, provides a capacity for recognition throughout an entire region and also in relation to the global context. The last element in profile development takes into consideration the university where the programme is anchored, its mission and strengths.