Miracle-dz/UniFAR-FTUs huggingface dataset:
Assessment of flow forces on large wood in rivers

Large wood (LW) exerts an important influence on the geomorphology and ecology of streams and rivers. The magnitudes of flow forces on LW are needed to support stream management activities and are typically computed using time mean lift and drag coefficients determined in laboratory flumes using small, smooth cylinders. Herein we report measurements of forces on LW of varying complexity (simple cylinder, branching, and complex root wad) and surface (bark) roughness made in an outdoor grassed channel under steady and unsteady flows. LW orientation relative to the primary flow direction and LW relative submergence were varied. Drag and lift coefficients for cylindrical (unbranched) LW followed patterns reported by others for metal cylinders in wind tunnels. Drag coefficients for cylindrical (unbranched) LW, corrected for blockage effects, ranged from −0.05 to 1.29, and lift coefficients ranged from −0.88 to 0.52, varying systematically with LW position relative to the channel bed and incident flow direction. Measured drag coefficients for the noncylindrical LW, corrected for blockage effects, ranged from 0.22 to 6.27, while lift coefficients varied from −3.65 to 30.84. Systematic relationships between the relative submergence and orientation of branching LW and the drag and lift coefficients were not observed, but coefficients were greatest for LW with few branches and converged on smaller values typical of blunt bodies as LW complexity increased. For both simple and complex LW, maximum lift and drag forces during the rising limb of unsteady flows were about 2–3 times greater than steady flow temporal mean values.
Comparison of simulation debriefs with traditional needs assessment methods: a qualitative exploratory study in a critical care community setting

Objective To better understand the potential of a needs assessment approach using qualitative data from manikin-based and virtual patient simulation debriefing sessions compared with traditional data collection methods (ie, focus groups and interviews). Design Original data from simulation debrief sessions was compared and contrasted with data from an earlier assessment of critical care needs in a community setting (using focus groups and interviews), thus undertaking secondary analysis of data. Time and cost data were also examined. Debrief sessions were coded using deductive and inductive techniques. Matrices were used to explore the commonalities, differences and emergent findings across the methods. Setting Critical care unit in a community hospital setting. Results Interviews and focus groups yielded 684 and 647 min of audio-recordings, respectively. The manikin-based debrief recordings averaged 22 min (total=130 min) and virtual patient debrief recordings averaged 31 min (total=186 min). The approximate cost for the interviews and focus groups was $13 560, for manikin-based simulation debriefs was $4030 and for the virtual patient debriefs was $3475. Fifteen of 20 total themes were common across the simulation debriefs and interview/focus group data. Simulation-specific themes were identified, including fidelity (environment, equipment and psychological) and the multiple roles of the simulation instructor (educative, promoting reflection and assessing needs). Conclusions Given current fiscal realities, the dual benefit of being educative and identifying needs is appealing. While simulation is an innovative method to conduct needs assessments, it is important to recognise that there are trade-offs with the selection of methods.
The effect of hydrographs on bed load transport and bed sediment spatial arrangement

[1] Field measurements of sediment transport in gravel bed rivers often reveal hysteretic effects due to differences in sediment availability between the rising and falling limbs of a flood hydrograph. However, only a small number of flume studies have analyzed the dynamics of sediment transport during hydrographs. Three types of stepped hydrographs with contrasting durations and magnitudes are simulated here under sediment recirculation conditions. Bed load transport rate and grain size have been measured continuously. The dynamic behavior of the surface armor layer has been explored by analyzing digital photographs and laser scanner surveys of the bed surface taken during hydrographs. The results indicate that sediment transport during the falling limb was lower than during the rising limb in all of the three types of hydrographs. This reduction is more evident for the low-magnitude hydrographs. The grain size of the bed remained virtually constant throughout the hydrographs but the grain size of transported sediments exhibited a counterclockwise hysteresis. Also, a significant increase in the reference shear stress for sediment entrainment was measured during the falling limb of hydrographs. Additionally, a detailed analysis of partial transport dynamics of the bed surface sediments reveals a reduction in sediment mobility during the falling limb of the hydrographs. The difference in sediment entrainment and transport before and after the peak of the hydrographs appears to be caused by a change in the organization of the surface sediments. An analysis of detailed laser scan bed surveys reveals a phase of bed restructuring (lower vertical roughness, clast rearrangement) during the falling limb of hydrographs. Consequently, changes in the degree of organization and complexity of the bed surface are likely the cause of the reduced mobility of sediments, and thus of the reduced sediment transport rate, during the falling limb of the hydrographs.
Soil as an important interface between agricultural activities and groundwater: leaching of nutrients and pesticides in the vadose zone

Abstract Agricultural non-point source pollution by plant nutrients and pesticides can cause severe environmental disturbances, such as deterioration in the quality of surface water and groundwater. In order to prevent this, the development and implementation of appropriate countermeasures are necessary, which requires knowledge of critical soil functions in the vadose zone. The nutrient source, the transport pathway and the availability of solutes in soil are some important conditions that affect leaching. Our results show that organic nitrogen sources are often more susceptible to leaching than inorganic N fertilizers, due to poor synchronization between the N demand of the crop and the release of inorganic N from the organic N source. Large amounts of leachable N are left in the soil after the growing season. Preferential flow, in combination with where soil solutes occur, is critical for establishing safe loading rates. In some cases, the solute is located in smaller pores of the soil matrix, and is thereby protected against preferential flow and leaching. In other cases, especially soon after application of a fertilizer or pesticide, transient flow-peaks rapidly displace the solutes through macropores in the vadose zone, which can cause large leaching loads and associated water-quality problems.
Spatial Thinking Ability Assessment in Rwandan Secondary Schools: Baseline Results

This article discusses use and modification of Lee and Bednarz’s (2012) Spatial Thinking Ability Test (STAT) as a spatial thinking assessment device in Rwandan secondary schools. After piloting and modifying the STAT, 222 students total from our rural and urban test schools and one control school were tested. Statistical analysis revealed that urban test school students outperformed rural test school students and that males outperformed females. Also observed were significant differences in performance for particular STAT question categories that can be used to inform strategies for spatial thinking curricular development and further modifications to the STAT in other contexts.
A seismic refraction technique used for subsurface investigations at Meteor Crater, Arizona

A seismic refraction technique for interpreting the subsurface shape and velocity distribution of an anomalous surface feature such as an impact crater is described. The method requires the existence of a relatively deep refracting horizon and combines data obtained from both standard shallow refraction spreads and distant offset shots by using the deep refractor as a source of initial arrivals. Results obtained from applying the technique to Meteor crater generally agree with the known structure of the crater deduced by other investigators and provide new data on an extensive fractured zone surrounding the crater. The breccia lens is computed to extend roughly 190 m below the crater floor, about 30 m less than the value deduced from early drilling data. Rocks around the crater are fractured as distant as 900 m from the rim crest and to a depth of at least 800 m beneath the crater floor.
A possible egg of the dromaeosaur Deinonychus antirrhopus: phylogenetic and biological implications

A unique find of a partial egg in contact with articulated gastralia from a known specimen of the dromaeosaurid Deinonychus antirrhopus (AMNH 3015) is described. Much of the original taphonomic context of the specimen was lost during the 1931 excavation and preparation, but enough information is preserved to provide strong evidence for a parental association between the adult skeleton and egg. The articulated nature of the gastralia suggests that the adult skeleton was at least partially articulated and had not suffered from either extensive subaerial exposure or postmortem transport, and the egg preservation also indicates in situ burial and postburial lithogenic crushing. Additional support stems from the presence of limey claystone matrix that indicates a low-energy depositional event. Phylogenetic characteristics of the eggshell microstructure are consistent with a theropod origin, and skeletochronological analysis suggests that AMNH 3015 was an adult and thus of breeding age bolstering the interpreta.
THE RAYNER COMPLEX OF EAST ANTARCTICA - COMPLEX ISOTOPIC SYSTEMATICS WITHIN A PROTEROZOIC MOBILE BELT

New isotopic (Rb–Sr, U–Pb zircon and Sm–Nd) and petrological data are presented for part of an extensive Proterozoic mobile belt (locally known as the Rayner Complex) in East Antarctica. Much of the belt is the product of Mid-Proterozoic (∼ 1800–2000 Ma) juvenile crustal formation. Melting of this crust at about 1500 Ma ago produced the felsic magmas from which the dominant orthogneisses of this terrain were subsequently derived. Deformation and transitional granulite-amphibolite facies conditions (which peaked at 750 ± 50°C and 7–8 kbar (0.7–0.8 GPa) produced open to tight folding about E–W axes and syn-tectonic granitoids about 960 Ma ago. Subsequent felsic magmatism occurred at about 770 Ma and not, as has been widely advocated, at 500–550 Ma, which appears to have been a time of widespread upper greenschist facies (400–500°C) metamorphism, localized shearing and faulting. Sm-Nd model ages of 1.65–2.18 Ga disprove a previously favoured hypothesis that the Rayner Complex mostly represents reworked Archaean rocks from the neighbouring craton (Napier Complex). Models that involve rehydration of the Napier Complex are no longer required, since the Rayner Complex was its own source of water. Two episodes of Proterozoic crustal growth are identified, the later of which occurred between about 1200 Ma and 1000 Ma, and was relatively minor. Sedimentation took place only shortly before Late Proterozoic orogenesis. The multiphase history of the Rayner Complex has resulted in complex isotopic behaviour. Three temporally discrete episodes of Pb loss from zircon have been identified, the earliest two of which are responses to the c. 960 Ma and 540 Ma tectonothermal events. Fluid leaching was operative during the later event for there is a good correlation between degree of isotopic discordance and secondary mineral growth. Pb loss during the high-grade event was probably governed by the same process or by lattice annealing. Some zircon suites also document recent Pb loss. Most lower concordia intercepts have no direct geological meaning and are explicable as mixed ages produced by incomplete Pb loss during two or more secondary events. Whereas all zircon separates from the orthogneisses produce U–Pb isotopic alignments, zircons from the only analysed paragneiss produce scattered data, in part reflecting a range of provenance. The 960 Ma event was also associated with the growth of a characteristically low U zircon (∼ 300 μg/g) in rocks of inferred high Zr content. There is ubiquitous evidence for the resetting of Rb–Sr total-rock isochrons. Even samples separated by up to 10 km fail to produce igneous crystallization ages. Minor mineralogical changes produced by the 540 Ma upper greenschist-facies metamorphism were sufficient to almost completely reset some Rb–Sr isochrons and to produce open system conditions on outcrop scale, at least in one location.
The 3D electromagnetic response of the Earth to ring current and auroral oval excitation

SUMMARY We report on a new compilation of functions representing the geoelectromagnetic response of the Earth’s mantle. The c response functions and newly defined d response functions, the latter of which constitutes a sensitive indicator of lateral heterogeneities in conductivity, were estimated for periods from 5 to 106.7 days. The spatial coverage and statistical quality of these response-function estimates were improved over previous compilations, in part by making use of a newly assembled global catalogue of magnetic observatory hourly mean values, and by applying a statistically robust form of empirical orthogonal function (EOF) analysis. The EOF results suggest that for periods longer than 5 days, the geomagnetic field variation can be represented predominantly by a single eigenmode. We have identified that the primarysource fields of the dominant mode consist of two current systems in the same direction: an equatorial ring current in the magnetosphere, and two conjugate auroral oval ring currents in the ionosphere. The influence of the auroral current system is seen at surprisingly low latitudes, 40 ◦ and 50 ◦ for the vertical and northern components, respectively, which results in non-negligible bias on the conventional c response at high latitudes. A preliminary correction of the auroral current effect has been made on the c and d responses obtained for data from 55 and 52 observatories, respectively, at latitudes from −60 ◦ to 60 ◦ . We also present a set of approximate equivalent internal (mantle) electrical current distributions that prove a useful indicator of the presence of deep Earth heterogeneities. These new sets of electromagnetic information will increase the resolving power of 3D distribution of electrical conductivity in the Earth’s mantle.
Propagating Subsurface Uncertainty to the Atmosphere Using Fully Coupled Stochastic Simulations

AbstractFeedbacks between the land surface and the atmosphere, manifested as mass and energy fluxes, are strongly correlated with soil moisture, making soil moisture an important factor in land–atmosphere interactions. It is shown that a reduction of the uncertainty in subsurface properties such as hydraulic conductivity (K) propagates into the atmosphere, resulting in a reduction in uncertainty in land–atmosphere feedbacks that yields more accurate atmospheric predictions. Using the fully coupled groundwater-to-atmosphere model ParFlow-WRF, which couples the hydrologic model ParFlow with the Weather Research and Forecasting (WRF) atmospheric model, responses in land–atmosphere feedbacks and wind patterns due to subsurface heterogeneity are simulated. Ensembles are generated by varying the spatial location of subsurface properties while maintaining the global statistics and correlation structure. This approach is common to the hydrologic sciences but uncommon in atmospheric simulations where ensemble fore.
Characterization of water quality variation in the Mekong River at Vientiane by frequent observations

To better understand the variation of water quality in the Mekong River, sampling and measurement were scheduled twice a week for about 3 years at Vientiane, followed by basic statistical analysis of the observed data. The frequent measurement revealed detailed characteristics of the water quality variation, which had not been detected by monthly observation in the previous studies. The variation in total ionic content was considered to be governed by dilution of the amount of water. Increases in turbidity could be attributed to physical effects including surface soil erosion and bed material resuspension at the time of discharge increase. Nitrogen concentrations were stably low during the low flow period and abruptly increased in May. After the annual maximum in late May, the nitrate concentration steadily decreased regardless of the remarkable rise in the discharge from mid‐July, whereas the ammonium concentration remained at a similar level until October. It was considered that the first small discernable runoff after the long dry season flushed the accumulated nitrogen in the surface soil and mobilized the nitrogen in the riverbed. The variation in phosphorus concentrations was different from that in nitrogen concentrations. During the high flow period, continual dilutions at discharge peaks and occasional large additions of phosphorus by surface runoff were suggested. Copyright © 2011 John Wiley & Sons, Ltd.
On leaf magnetic homogeneity in particulate matter biomonitoring studies

Biomonitoring of magnetic properties of tree leaves has been postulated to be a good approach to measure particulate matter (PM) pollution levels. We studied the variation of magnetic hysteresis parameters on leaves of Quercus ilex, an evergreen oak previously used for magnetic biomonitoring of air pollution in Rome (Italy). The hysteresis parameters (MRS, MS, BCR and BC) measured on specimens collected at a close spacing on the surface of two single leaves show variances that are smaller than those observed on a collection of Q. ilex leaves sampled from several trees distributed along high‐traffic roads. The variability is higher for magnetizations than for coercivities. This suggests a uniform source for the magnetic particles, such that variations are due mainly to changes in concentration. The normalized hysteresis cycles are remarkably similar for all the specimens. Normalization of magnetic moments by mass appears however more efficient than normalization by volume.
Effect of addition of tire chips on the unconfined compressive strength of fly ash-lime-gypsum mixture

Abstract Standard Proctor compaction tests were carried out to obtain the optimum reference mix containing fly ash + 8% lime + 0.9% gypsum. The result of light compaction study reveal that addition of small percentage of gypsum (less than 1%) to the fly ash + 8% lime mix has no effect on the dry unit weight and optimum moisture content. The reference mix so obtained was mixed with randomly distributed dry/wet tire chips to study the unconfined compressive strength, energy absorption capacity and cracking pattern of the specimen by varying the tire chip content (5% to 15%), curing period (7 days to 180 days) and curing methods. The results of this study indicated that unconfined compressive strength, energy absorption capacity and cracking pattern of the reference mix containing dry/wet tire chips is influenced by the tire chip content, curing period and curing method. The study further reveals that the unconfined compressive strength and energy absorption capacity of specimen can be increased using wet tire chips in comparison to dry tire chip in the reference mix. Study on unit weight reveals that it decreases with the increase in tire chip content in the reference mix. Further the specimens containing 5% dry/wet tire chip content were observed to fail by development of multiple cracking where as specimen with higher percentage (15%) of dry/wet tire chips results in zig-zag cracking behavior of the specimen. The reference mix with wet tire chips can be a good material for road sub base having light traffic and disposal of these materials will be in an environmental friendly manner.
Paleolimnological Reconstruction of Hydrologic Change in the Slave River and Great Slave Lake During the Past Millennium

The Slave River Delta (SRD), NWT, represents a pivotal node in the upper Mackenzie Basin watershed and is a productive northern wetland landscape with a rich natural and cultural heritage. Concerns over environmental consequences of natural and anthropogenic-driven decline in river discharge as well as climate variability have prompted hydroecological studies to improve understanding of how this ecosystem functions over time and space. However, long-term natural hydrological variability of the Slave River system is not well documented and needs to be further developed. In order to provide a temporal context for understanding and evaluating the impacts of climate variability and change and other stressors on Slave River discharge, multi-proxy paleolimnological analyses have been conducted to reconstruct a long-term record of hydrologic variability in the Slave River system. Study sites include two small closeddrainage lakes (GSL1, SD34) located near a former elevated strandline of Great Slave Lake and another lake (SRI) located upstream on an island in the Slave River. Multi-proxy analysis of lake sediment cores collected from SD34, GSL1 and SRI provided a -1200-year record of water level variation for the Slave River and Great Slave Lake. Sediment composition and elemental and stable isotope geochemistry proved to be sensitive indicators of hydrologic change within the study basins. Interpretation of C/N ratios and 5 Corg values from SD34, GSL1 and SRI additionally indicated that conventional, straightforward interpretation of these commonly applied paleolimnological measurements is not always appropriate. Prior to the onset of the last millennium, during the Early Medieval period (MP), high C/N ratios, low 50|W, high 5 1 Corg and inorganic sediment indicated open-drainage
Abonos verdes: Tecnología para el manejo agroecológico de los cultivos

In order to find management alternatives for improving the fertility of soils cultivated by low-income farmers, agroecological technologies have been used such as green manures (GM) whose contributions to worldwide research seek to generate a theoretical base which explains the importance of its application and potentialities in the management of agroecosystems. Its use is based on the exploitation of solar energy to produce plant biomass of high nutritional quality, which then is added or incorporated into the soil with the purpose of increasing the organic matter content rapidly mineralizable, with positive effects on some physical, chemical, biological properties of soils and yields of the posterior crops. Legumes are used alone or mixed generally, which in symbiosis with rhizobia acquire the ability to fix atmospheric N 2 , which is an element that circulates through the symbiont plant and then partially incorporates to the soil to be used by crops that are planted with commercial interests. This practice (GM) reduces significantly the use of fertilizers of industrial chemical synthesis. In this way, besides the direct benefits on the soil, there are others of an economic, social and environmental type which point towards a more sustainable agriculture. In Latin America and Colombia, some institutions, through research projects and international cooperation have contributed to generate information about this culture technology and the possibilities of incorporating it by farmers in their agricultural schedules. However, replication studies in different agro-ecological zones are required as well as the incorporation of methodological tools to validate the nature of the GM as multipurpose technology.