Miracle-dz/UniFAR-FTUs huggingface dataset:
First observations of polar mesosphere summer echoes in Antarctica

A 25-kW peak power 50-MHz radar was installed at the Peruvian base on King George Island, Antarctica (62°S), in early 1993. A search for polar mesospheric summer echoes (PMSEs) was made during late January and early February of the first year of operation with negative results. These results have been reported in the literature [Balsley et al., 1993; 1995]. We report here results obtained during the austral summer of the second year (1994) of operation. Observations during the second year were begun earlier, i.e., closer to the austral summer solstice. PMSEs were observed during this period, albeit the echoes were much weaker than what one would expect based on earlier Poker Flat radar results at a comparable latitude (65°N) in the Northern Hemisphere. A large and measurable asymmetry in PMSE strength in the two hemispheres therefore exists. We explain this asymmetry by postulating a difference in summer mesopause temperatures between the two hemispheres of ∼7.5 K. This difference has been estimated using an empirical relationship between the variations of the Poker Flat PMSE power as a function of temperature given by the mass spectrometer incoherent scatter extended (MSISE-90) model.
Evaluation of Groundwater Quality and Its Suitability for Domestic and Irrigation Use in Parts of the Chandauli-Varanasi Region, Uttar Pradesh, India

The present study focused on the hydrochemistry of groundwater in parts of Chandauli-Varanasi region to assess the quality of groundwater for determining its suitability for drinking and agricultural purposes. Urbanization and agriculture activities have a lot of impacts on the groundwater quality of the study area. A total of 70 ground water samples were collected randomly from different sources viz. hand pump, dug wells and bore wells, and analyzed for major cations and anions. The domination of cations and anions was in the order of Na > Ca > Mg > K and HCO3 > Cl > SO4 > NO3 > F. The Piper classification for hydrogeochemical facies indicates that alkaline earth exceeds alkalis and weak acids exceed strong acid. Water quality index rating was calculated to quantify overall water quality for human consumption. Out of 70 groundwater samples, 7% and 10% samples exhibit water unsuitable for drinking purposes in pre- and post-monsoon, respectively, due to effective leaching of ions, direct discharge of domestic effluents and agricultural activities. Residual sodium carbonate values revealed that 6% sample is not suitable for irrigation purposes in both the seasons due to low permeability of the soil. The calculated values of PI indicate that the water for irrigation uses is excellent to good quality in both seasons. As per Wilcox’s diagram and US salinity laboratory classification, most of the groundwater samples are suitable for irrigation except one sample which is unsuitable for irrigation purposes. The overall quality of groundwater in post-monsoon season in all chemical constituents is on the higher side due to dissolution of surface pollutants during the infiltration and percolation of rainwater at few places due to agricultural and domestic activities.
Seismic wave propagation through material containing partially saturated cracks

SUMMARY Expressions for the wave speeds and attenuation of elastic waves through material containing aligned cracks are available in an approximation valid up to second order in the number density of cracks and for wavelengths that are long compared with the size of the cracks. Conditions within the crack may vary from dry (stress-free) to fluid or solid-filled. The situation where cracks are partially filled with liquid (and part with gas) is very different from either extreme of dry or liquid-filled cracks since the liquid is forced to flow laterally within a crack, at the expense of the more compressible gas, by tensions or compressions imposed normal to the plane of the crack. Expressions are derived here which enable the range of internal crack-conditions to be extended to the case of partial saturation in the formulae for the propagation characteristics of waves of long wavelength through material containing such cracks.
Design and Analysis of Cluster Randomization Trials in Health Research

Acknowledgements. Preface. 1. Introduction. 1.1 Why randomize clusters? 1.2 What is the impact of cluster randomization on the design and analysis of a trial? 1.3 Quantifying the effect of clustering. 1.4 Randomized versus non-randomized comparisons. 1.5 The unit of inference. 1.6 Terminology: what's in a name? 2. The historical development of cluster randomized trials. 2.1 Randomized trials before 1950. 2.2 Cluster randomized trials between 1950 and 1978. 2.3 Cluster randomized trails since 1978. 3. Issues arising in the planning of cluster randomization trials. 3.1 Selecting interventions. 3.2 Setting eligibility criteria. 3.3 Measuring subject response. 3.4 The most commonly used experimental designs. 3.5 Factorial and crossover designs. 3.6 Selecting an experimental design. 3.7 The importance of cluster-level replication. 3.8 Strategies for conducting successful trials. 4. The role of informed consent and other ethical issues. 4.1 The risk of harm. 4.2 Informed consent. 4.3 Subject blindness and informed consent. 4.4 Randomized consent designs. 4.5 Ethical issues and trial monitoring. 5. Sample size estimation for cluster randomization designs. 5.1 General issues of sample size estimation. 5.2 The completely randomized design. 5.3 The matched-pair design. 5.4 The stratified design. 5.5 Issues involving losses to follow-up. 5.6 Strategies for achieving desired power. 6. Analysis of binary outcomes. 6.1 Selecting the unit of analysis. 6.2 The completely randomized design. 6.3 The matched-pair design. 6.4 The stratified design. 7. Analysis of quantitative outcomes. 7.1 The completely randomized design. 7.2 The matched-pair design. 7.3 The stratified design. 8. Analysis of count, time to event and categorical outcomes. 8.1 Count and time to event data. 8.2 Categorical data. 9. Reporting of cluster randomization trials. 9.1 Reporting of study design. 9.2 Reporting of study results. References. Index.
High‐frequency source radiation during the 2011 Tohoku‐Oki earthquake, Japan, inferred from KiK‐net strong‐motion seismograms

To investigate source processes of the 2011 Tohoku‐Oki earthquake, we utilized a source location method using high‐frequency (5−10 Hz) seismic amplitudes. In this method, we assumed far‐field isotropic radiation of S waves, and conducted a spatial grid search to find the best fitting source locations along the subducted slab in each successive time window. Our application of the method to the Tohoku‐Oki earthquake resulted in artifact source locations at shallow depths near the trench caused by limited station coverage and noise effects. We then assumed various source node distributions along the plate, and found that the observed seismograms were most reasonably explained when assuming deep source nodes. This result suggests that the high‐frequency seismic waves were radiated at deeper depths during the earthquake, a feature which is consistent with results obtained from teleseismic back‐projection and strong‐motion source model studies. We identified three high‐frequency subevents, and compared them with the moment‐rate function estimated from low‐frequency seismograms. Our comparison indicated that no significant moment release occurred during the first high‐frequency subevent and the largest moment‐release pulse occurred almost simultaneously with the second high‐frequency subevent. We speculated that the initial slow rupture propagated bilaterally from the hypocenter toward the land and trench. The landward subshear rupture propagation consisted of three successive high‐frequency subevents. The trenchward propagation ruptured the strong asperity and released the largest moment near the trench.
Bathymetry and geological structures beneath the Ross Ice Shelf at the mouth of Whillans Ice Stream, West Antarctica, modeled from ground‐based gravity measurements

New gravity data reveal important geologic controls on the location and behavior of the grounding zone of Whillans Ice Stream (WIS), West Antarctica. Grounding zones of ice sheets and contiguous ice shelves are important for understanding ice sheet dynamics, as key processes that influence the grounded ice and its discharge into the ocean occur in these regions. Here, we model the bathymetry and shallow geological structures beneath the Ross Ice Shelf in an embayment of the WIS grounding zone using gravity data collected on the ground, in conjunction with seismic and radar data. We find that the region of shallow ocean water (<~50 m) is extensive; oceanographic models suggest that grounding zones exhibiting thin ocean cavities with gently sloping ice‐ocean interfaces are likely to be tidally well mixed, leading to slower basal melting than would occur in a thicker, stratified water column. Beneath the ocean water column, we model a fault and a sedimentary basin in a half‐graben, filled with two layers of sediments. The total thickness of the sediment layer is 900 to 1250 m in the half‐graben, and 600 to 800 m on the upthrown block, and the basement depth is no more than 2000 m. We observe that the upper, softer sediment is thinnest near the modern grounding line and may possibly pinch out near our grid, and that the modeled fault is roughly parallel to part the grounding. We therefore hypothesize that the WIS grounding line stabilized in its current location in part due to the subglacial geology.
Antarctic non-stationary signals derived from Seasat-ERS-1 altimetry comparison

Geographical changes in the height of the Antarctic ice sheet between 1978 and 1992 are mapped using altimeter data from Seasat and ERS-1 via an inverse technique that allows us to take imo account the whole altimctric error budget. in a belt between 70° and 72° S and between 150° and 80° E, a precision better than 40 cm is found for the surface elevation change, while the change in height averaged in the along-slopc direction has a precision of around 10-20 cm, leading to a precision better than 10% of the mass balance. These data suggest a relative positive imbalance of around 20% in this sector for the western and high-altitude areas, and a relative negative imbalance in some areas of lower altitude.
Levels of 14C in the Terrestrial Environment in the Vicinity of Two European Nuclear Power Plants

Radiocarbon is produced in all types of nuclear reactors. Most of the 14C released into the environment is in the form of gaseous emissions. Recent data on the 14C concentration found in terrestrial samples taken in the vicinity of nuclear power plants in Romania and Lithuania are presented. We found increased 14C levels in the surroundings of both power plants. At the Romanian power plant Cernavoda, we found excess levels of 14C in grass within a distance of about 1000 m, the highest 14C specific activity being 311 Bq/kg C (approximately 28% above the contemporary 14C background) found at a distance of 200 m from the point of release (nearest sampling location). At the Lithuanian power plant Ignalina, samples of willow, pine, and spruce showed a 14C excess of similar magnitude, while significantly higher values were found in moss samples. The samples were analyzed at the accelerator mass spectrometry facility in Lund, Sweden.
Objective determination of snow-grain characteristics from images

The determination of snow-grain characteristics (such as type or size) is crucial for validating snow models and interpreting remote-sensing data. Until now, the size and type of snow grains have been estimated in the field. Nowadays, the transport of a snow sample in iso-octane allows laboratory analyses. The objective analysis of snow-grain digital images has been developed at the Centre d'Études de la Neige since the mid 1980s. The images are taken in a cold room and stored on a video disk. The calculation of the relevant parameters for snow characterization has been developed. Recently, the hardware- and software-systems have been upgraded, allowing quicker and easier analyses. Finally, a procedure designed to determine snow types from image analysis has been developed and calibrated using 65 snow samples. For that purpose, independent experts have determined the snow type (as defined by the International Classification) of each sample. The procedure has been verified using an independent set of snow images. This semi-automated determination gives 97% correct results on granular-snow types. However, it is not reliable for precipitation particles.
Hydrothermal inoculation and incubation of the chalcopyrite disease in sphalerite

Chalcopyrite disease, consisting of a multitude of submicron- to micron-sized blebs of chalcopyrite concentrated along fractures or rims or in relatively iron-rich bands of sphalerite crystals, is a common ore texture which is critical to the understanding of the paragenesis of many ore deposits. It has now been synthesized in the laboratory by hydrothermal interaction of sphalerite with a hot copper-bearing fluid (Bourcier et al., 1984; Eldridge, 1984). Experimental conditions approximated those of the copper mineralization period of a kuroko orebody as set out by Ohmoto et al. (1983). Massive replacement of sphalerite by chalcocite, resembling supergene zone textures, occurred when starting solutions were highly supersaturated in copper with respect to copper sulfides. Chalcopyrite disease textures were formed only when starting solutions were close to equilibrium with chalcopyrite. The disease appears to have grown by the replacement of the FeS component of sphalerite, as suggested by Barton (1978), and the reaction governing the process is likely to be:Zn (sub 0.80) Fe (sub 0.20) S + 0.20Cu (super +) + 0.20H (super +) = 0.60ZnS + 0.20CuFeS 2 + 0.20Zn (super +2) + 0.10H 2 . This reaction has a small negative volume change, implying that the process is not self-limiting if Zn (super +2) and H 2 are continually removed from the system. The disease may even continue growth with additional iron from solution before attaining a positive delta V. Marcasite, intergrown with the sphalerite used in the experiment, was also partially replaced by chalcopyrite, perhaps in a process linked by recycling of the H 2 produced in the reaction above, according to the reaction:FeS 2 + Cu (super +) + 0.5H 2 = CuFeS 2 + H (super +) . It appears that the chalcopyrite disease represents the earliest stages of replacement of sphalerite by chalcopyrite and that the process may proceed to total replacement. The disease process, together with the chemically sympathetic replacement of iron sulfides by chalcopyrite, may explain how a kuroko-type orebody may have a stratigraphy that is the inverse of its paragenesis and how copper-rich cores of sea-floor, high-temperature, hydrothermal chimneys progress outward through the earlier formed zinc-rich rims. The overall replacement of iron and zinc sulfides by chalcopyrite may be represented by the reaction:FeS 2 + 2ZnS + Fe (super +2) + 2Cu (super +) = 2CuFeS 2 + 2Zn (super +2) .
Oceanic crust generation in an island arc tectonic setting, SE Anatolian orogenic belt (Turkey)

A number of Late Cretaceous ophiolitic bodies are located between the metamorphic massifs of the southeast Anatolian orogenic system. One of them, the Göksun ophiolite (northern Kahramanmaraş), which crops out in a tectonic window bounded by the Malatya metamorphic units on both the north and south, is located in the EW-trending nappe zone of the southeast Anatolian orogenic belt between Göksun and Afşin (northern Kahramanmaraş). It consists of ultramafic–mafic cumulates, isotropic gabbro, a sheeted dyke complex, plagiogranite, volcanic rocks and associated volcanosedimentary units. The ophiolitic rocks and the tectonically overlying Malatya–Keban metamorphic units were intruded by syn-collisional granitoids (∼ 85 Ma). The volcanic units are characterized by a wide spectrum of rocks ranging in composition from basalt to rhyolite. The sheeted dykes consist of diabase and microdiorite, whereas the isotropic gabbros consist of gabbro, diorite and quartzdiorite. The magmatic rocks in the Göksun ophiolite are part of a co-magmatic differentiated series of subalkaline tholeiites. Selective enrichment of some LIL elements (Rb, Ba, K, Sr and Th) and depletion of the HFS elements (Nb, Ta, Ti, Zr) relative to N-MORB are the main features of the upper crustal rocks. The presence of negative anomalies for Ta, Nb, Ti, the ratios of selected trace elements (Nb/Th, Th/Yb, Ta/Yb) and normalized REE patterns all are indicative of a subduction-related environment. All the geochemical evidence both from the volcanic rocks and the deeper levels (sheeted dykes and isotropic gabbro) show that the Göksun ophiolite formed during the mature stage of a suprasubduction zone (SSZ) tectonic setting in the southern branch of the Neotethyan ocean between the Malatya–Keban platform to the north and the Arabian platform to the south during Late Cretaceous times. Geological, geochronological and petrological data on the Göksun ophiolite and the Baskil magmatic arc suggest that there were two subduction zones, the first one dipping beneath the Malatya–Keban platform, generating the Baskil magmatic arc and the second one further south within the ocean basin, generating the Göksun ophiolite in a suprasubduction zone environment.
Hypersaline Burial Diagenesis Delineated by Component Isotopic Analysis, Late Paleozoic Limestones, West Texas

ABSTRACT Pennsylvanian to Lower Permian cyclic platform carbonates from the Southwest Andrews area of West Texas are now 3 km below the land surface. Isolated samples of brachiopod shell, zones of calcite cement, and saddle dolomite from limestone cores of the Southwest Andrews oilfields have been analyzed isotopically to determine if: (1) diagenesis is dominated by early, meteoric processes, as suggested by bulk rock isotopes, (2) whether significant burial diagenesis occurred in hypersaline waters, and (3) whether most burial cements are allochthonous or internally derived. Bulk isotopic analyses of limestones show systematic variation in 13C and 18O according to length of subaerial exposure and stratigraphic position. Chemically zoned calcite cements show four growth stages. Stage 1 and 2 cements have average 13C values of -4.6o/oo and average 18O of -5.0o/oo, and most are interpreted to have precipitated during subaerial exposure in meteoric water. A few stage 1 cements with average 13C values of -4.7o/oo and 18O of -1.4o/oo apparently precipitated below the sediment surface from modified seawater in a sulfate reduction zone. Stage 3 and 4 calcite cements precipitated after compaction and compose up to 25% of the total rock volume. They have 13C values (-0.2o/oo to -4.4o/oo) that vary according to stratigraphic position, and are similar to bulk rock samples of the host limestone. The 13C values indicate local derivation by dissolution of adjacent rock. The 18O values of stage 3 and 4 cement (-5.5o/oo to -3.5o/oo) are indistinguishable from stages 1 and 2 cements precipitated from meteoric water. The decrease in 18O expected from elevated temperatures during burial (present formation temperature of 55°C) is negated by precipitation from a late Permian brine with 18O values of +5o/oo. Stages 3 and 4 calcite and saddle dolomite cements have 87Sr/86Sr values that are lower than 87Sr/86Sr values for contemporaneous marine carbonate ( 0.70830). This is probably due to incorporation of Sr with low 87Sr/86Sr values (0.70672 to 0.70682) also from the late Permian hypersaline brine. The Southwest Andrews area has several diagenetic features that are probably more common in ancient limestone than previously recognized. (1) Burial cements have 18O values similar to meteoric cements when precipitated from hypersaline waters with 18O values 5o/oo greater than contemporary seawater. (2) Deep-burial cements have 13C values similar to the bulk rock because carbon is derived from pressure dissolution of nearby carbonate. (3) Bulk-rock isotope values are characteristic of marine limestones subjected to meteoric diagenesis, even though they have suffered substantial deep burial diagenesis. This study clearly illustrates the value of analyzing diagenetic components to accurately understand porosity evolution in limestones.
Clues from a Shocked Meteorite

Earth9s crust contains higher abundances of alkali metals than the mantle. In the crust, feldspars are the key hosts for alkali metals, but which minerals are involved in processing alkali metals in the deep Earth is not known. As Akaogi discusses in this Perspective, a high-pressure mineral called hollandite has all the right properties to act as a deep Earth alkali host. This mineral has been produced in high-pressure experiments and has now also been identified in a shocked meteorite by Gillet et al. (page 1633).
Analisis Faktor-Faktor yang Mempengaruhi Peringkat Obligasi Syariah: Studi Empiris Pada Pasar Obligasi Syariah di Indonesia

This study aims to examine the factors that affect the ranking of Islamic bonds in the bond market in Indonesia. Specifically, this study will examine the influence of risk factors such as firm size, leverage, profitability, coverage, firm age and bank debt, 2) risk factors, namely maturity bond, bond size, and duration; 3 ) non- financial risk factors, that the auditor quality toward Indonesian Islamic bond ratings. The population in this study are all companies that issue bonds in the period 2006-2010. Sampling was conducted with a purposive sampling approach and produce 48 samples observasian. The analysis was performed with multiple regression models . The analysis showed that the factors affecting the Islamic bond ranking is firm size. This means that size firm is a factor considered in the rank of Islamic bonds.
COASTAL AND OCEANIC FISH LARVAE IN AN AREA OF UPWELLING OFF YAQUINA BAY~ OREGON

A 1'h-yr survey of planktonic fish larvae collected from 2 to 111 km off the mid-Oregon coast in 1971·72yielded 287 sampleswhich contained 23,578 individuals in 90 taxonomic groups, 78 identified at the species level. Two distinct faunal assemblages were found: a "coastal" assemblage 2 to 28 km offshore and an "offshore" assemblage 37 to 111 km from shore. The coastal group was dominated by Osmeridae, Parophrys vetulus, Isopsetta isolepis, and Microgadus proximus. The offshore group was dominated by Sebastes spp. , Stenobrachius leucopsarus, Tarletonbeania crenularis, Lyopsetta exilis, and Engraulis mordax. Peak abundance in both assemblages occurred between February andJuly when >90% ofall larvae were taken. Larval distribution patterns in eachassemblage were similarin 1971 and 1972,but larval abundance was greater in 1971 than 1972. Ninety-nine percent ofthe larvae in 53 taxa designated as coastal and 96% ofthe larvae in 31 taxa designated as offshore were taken 2 to 28 km or 37 to 111 km offshore respectively. This separation of coastal and offshore larvae may be explained, in part, by adult spawning locations and current circulation patterns. The species oflarvae present in the coastal assemblage were similar to those in Yaquina Bay, but dominant species were quite different. The coastal zone is an important spawning area for P. vetulus, which utilizes Yaquina Bay estuary as a nursery during part of its early life.