Miracle-dz/UniFAR-FTUs huggingface dataset:
First global positioning system results in northern Myanmar: Constant and localized slip rate along the Sagaing fault

We present the first recorded global positioning system (GPS) data from Myanmar measured at the northern tip of the Sagaing fault. This area is in a very complex geodynamic context, where rigid and semirigid plates interact. The 12 GPS sites measured in 2005 and 2008 in northern Myanmar show that the slip rate is 18 mm/yr and is localized along a single active narrow fault trace (<20 km wide). The same rate was previously demonstrated and remeasured, 500 km southward, in central Myanmar. Despite the geodynamic regional complexity induced by interaction between the Sunda and India plates, the Burma microplate, and the highly deformable eastern Himalayan syntaxis, the slip rate remains surprisingly constant along this fault. However, the modeled locking depth varies from 20 km in central Myanmar to 5 km in the north.
Participative leadership and organizational identification in SMEs in the MENA Region: testing the roles of CSR perceptions and pride in membership. Ethics

The aim of this research is to explore the process linking participative leadership to organizational identification. The study examines the relationship between participative leadership and internal CSR perceptions of employees and also investigates the role that pride in membership plays in the affiliation of CSR perceptions with organizational identification. By studying these relationships, the paper aspires to contemplate new presumed mediators in the association of participative leadership with organizational identification as well as determine a possible novel antecedent of employee CSR perceptions. Empirical evidence is provided from data that was collected through a survey distributed to employees working for small and medium sized enterprises in three countries in the Middle East and North Africa region, particularly the United Arab Emirates, Lebanon, and Tunisia. Findings show that participative leadership leads to positive internal CSR perceptions of employees and that these CSR perceptions lead to pride in membership which, in turn, results in organizational identification. Implications of these findings are also discussed.
Automorphisms of surfaces over fields of positive characteristic

We study automorphism and birational automorphism groups of varieties over fields of positive characteristic from the point of view of Jordan and $p$-Jordan property. In particular, we show that the Cremona group of rank $2$ over a field of characteristic $p>0$ is $p$-Jordan, and the birational automorphism group of an arbitrary geometrically irreducible algebraic surface is nilpotently $p$-Jordan of class at most $2$. Also, we show that the automorphism group of a smooth geometrically irreducible projective variety of non-negative Kodaira dimension is Jordan in the usual sense.
Solar cycle signature and secular long‐term trend in OH airglow temperature observations at South Pole, Antarctica

[1] We have examined Michelson Interferometer OH airglow temperature data to investigate solar cycle and long-term variations of mesospheric temperatures at South Pole Station (SPS), Antarctica (90°S). The data set used here is continuous (24 hours a day) and taken during 1994–2004 austral winters. We have used a Multiple Linear Regression (MLR) technique to elucidate solar cycle and the trend term in the MI temperature time series data. The 11-year time series of OH rotational temperature shows a strong correlation with F10.7 radio flux (R = 0.60). The amplitude of solar cycle response seen in the mesopause temperature records at South Pole is about 0.04 ± 0.01 K/sfu (Solar Flux Units), however, the trend term is statistically insignificant and is about 0.1 ± 0.2 K/year. Superposed epoch studies have been carried out in order to determine climatological variations in OH temperatures above South Pole derived from 11 years of austral winter observations. The mean amplitude of this variation is about 12.6 K and its maximum occurs near 30 May which is in agreement with the Fabry-Perot Spectrometer (FPS) observations of OH temperatures at SPS (Hernandez, 2003). However, whereas Hernandez (2003) reported 35 K cooling in 2002, MI OH temperatures at SPS do not show any significant deviation from previous years.
CONSOLIDATION BY VERTICAL DRAINS

A theory is described which can be used in designing a vertical drainage system. This theory incorporates important parameters such as vertical discharge capacity, remoulding effects during installation and filter resistance. The importance of these parameters is widely recognized, but very seldom taken into account in the design, by engineers. Six well-documented case records, related to different drain types are briefly presented. Experience gained from these case records shows that in many cases, even if the overall performance appears successful, there are aspects of soil/drain behaviour that cannot be explained on the basis of existing theories. L'article decrit une theorie que l'on peut appliquer a la conception d'un systeme de drainage vertical. Cette theorie renferme d'importants parametres tels que la capacite de decharge verticale, les effets du remaniement pendant l'installation et la resistance de filtration. L'importance de ces parametres est reconnue par bien des ingenieurs, mais ils en tien.
Prediction of Tropical Cyclone Rapid Intensification Events

Abstract : The largest errors in tropical cyclone intensity forecasting are usually the result of rapid intensification events, where rapid intensification is defined as a change in minimum central pressure of at least 42 hP sub a in a 24 hour period, or a satellite-inferred increase in maximum sustained winds of a least 23 m/s 1 per day when no measurement of central pressure is possible. An observational and theoretical study is made of the unique characteristics of rapidly intensifying typhoons in the western North Pacific. Climatological data, digital infrared satellite imagery and composited rawinsonde sounding data within 5 deg of the center of tropical cyclones were used to identify the distinctive features associated with rapid intensifiers when compared to other stratifications of non-rapid intensifiers and non-intensifiers. Rapid intensity change is indicated on satellite imagery as an extreme concentration of convection near the cyclone center. Relative concentrations of inner and outer deep cumulus convection reveal a predictive relationship between the ratio of inner core to outer core convection and the onset of rapid intensity change 12 hours later. This prediction technique was found to successfully forecast rapid or non-rapid intensification in over 90% of the cases in a three-year study of 70 northwest Pacific tropical cyclones. A physical explanation of the likely processes associated with rapid intensification is also presented. Rapid intensification is believed to be the result of weak asymmetrical wind flow across the cyclone at upper levels of the troposphere. Rapid intensifiers are shown to have large warm anomalies near the tropopause and weak vertical shear of tangential winds below 150 hP sub a. Theses.
Optimized stomatal conductance of vegetated land surfaces and its effects on simulated productivity and climate

The stomatal conductance of terrestrial vegetation affects the exchange fluxes of water and carbon at the land surface. Here, a dynamic vegetation model coupled to a climate model of intermediate complexity is used to demonstrate that an optimum stomatal conductance exists at which the rate of photosynthesis, and therefore vegetation productivity, is at a maximum. This maximum originates from two competing drivers that affect the rate of photosynthesis: (i) increased supply of atmospheric carbon dioxide with increased stomatal conductance and (ii) increased cloud cover, which reduces the supply of sunlight. The simulated climate with optimized stomatal conductance is close to the model's control simulation, but vegetation productivity is substantially enhanced. The existence of this optimum has potentially important implications for the adaptation of terrestrial productivity to different climates. If vegetation maintains this optimum not only in the present‐day, but also adapts to it during past (and future) climates, not considering this optimum and how it changes leads to a general underestimation of terrestrial productivity under different climates.
Ammonium in coastal Antarctic aerosol and snow: Role of polar ocean and penguin emissions

Year-round aerosol samples collected in the boundary layer at coastal Antarctic sites (Dumont D'Urville, Neumayer, and Halley) indicate a seasonal cycle of ammonium concentrations with a minimum in winter (April–September). A large intersite difference appears in the summer (November–February) maxima values, from ∼12.5 ng m−3 at Neumayer to 140–230 ng m−3 at Dumont D'Urville. At Dumont D'Urville, ammonium concentrations are the largest ever reported from Antarctic sites, and the large summer maxima are associated with large enrichments with respect to sea salt for potassium and calcium. In addition, seasonal ammonium variations at Dumont D'Urville are in phase with a well-marked seasonal cycle of oxalate concentrations which exhibit maxima of 5–10 ng m−3 in spring and summer and minima of less than 0.5 ng m−3 in winter. Such a composition of aerosols present in the boundary layer at Dumont D'Urville in summer is linked to the presence of a large Adelie penguin population from the end of October to March at the site. Ornithogenic soils (defined as guano-enriched soils), together with the bacterial decomposition of uric acid, are a source of ammonium, oxalate, and cation (such as potassium and calcium) aerosol, in addition to a subsequent large ammonia loss from ornithogenic soils to the atmosphere. The total breeding population of 5 million Adelie penguins widely distributed around the Antarctic continent may emit, at most, some 2.5 × 10−4 Mt of NH3-N during the summer months. In contrast, Halley and Neumayer Stations are far less exposed to penguin colony emissions. At Neumayer, ammonium concentrations peak from January to March and are in phase with the increase of biogenic sulfur species. Here the NH4+/(MSA + nss SO4−) molar ratio is close to 13% in summer aerosol and to 40% in winter aerosol. Using this summer ratio, which may be related to ammonia and sulfur oceanic emissions occurring south of 50°S in summer and estimated DMS emissions in these regions at this time, we derive an upper limit of 0.064 Mt NH3-N emitted per year by the high-latitude Southern Ocean in summer. This study indicates a very limited ammonia neutralization of acidic sulfate aerosols at high southern latitudes, except in the vicinity of ornithogenic soils occupied by large penguin colonies.
A Mechanism for Land–Atmosphere Feedback Involving Planetary Wave Structures

AbstractWhile the ability of land surface conditions to influence the atmosphere has been demonstrated in various modeling and observational studies, the precise mechanisms by which land–atmosphere feedback occurs are still largely unknown: particularly the mechanisms that allow land moisture state in one region to affect atmospheric conditions in another. Such remote impacts are examined here in the context of atmospheric general circulation model (AGCM) simulations, leading to the identification of one potential mechanism: the phase locking and amplification of a planetary wave through the imposition of a spatial pattern of soil moisture at the land surface. This mechanism, shown here to be relevant in the AGCM, apparently also operates in nature, as suggested by supporting evidence found in reanalysis data.
Interaction of HNO3 with water‐ice surfaces at temperatures of the free troposphere

The uptake of gas‐phase HNO3 by water‐ice films has been measured in a low‐temperature, coated‐wall flow tube under conditions where water‐ice, and not a hydrate of nitric acid, is thermodynamically stable. It is observed that there is uptake of HNO3 on the order of 1 → 3 ×1014 molecules per cm² of ice film on a short timescale, and a somewhat smaller uptake on a much longer timescale of 10's of minutes. The short timescale uptake is insensitive to the nitric acid partial pressure, varying by not more than a factor of two over a 20‐fold variation in the partial pressure of HNO3 from 1.3 × 10−7 to 3.1 × 10−6 torr. This implies that the ice surface is saturated with HNO3 at these partial pressures. Also, the uptake is somewhat dependent on temperature over the range 208 to 248 K, with the largest uptake at the lowest temperatures. The uptake is largely irreversible, with only 20 → 25% of the adsorbed HNO3 desorbing from the film when the exposure to gas‐phase HNO3 is stopped. These experiments suggest that adsorption to cirrus cloud surfaces may be an important scavenging process of HNO3 in the troposphere.
Comment on ‘Physics-based representations for machine learning properties of chemical reactions’

In a recent article in this journal, van Gerwen et al (2022 Mach. Learn.: Sci. Technol. 3 045005) presented a kernel ridge regression model to predict reaction barrier heights. Here, we comment on the utility of that model and present references and results that contradict several statements made in that article. Our primary interest is to offer a broader perspective by presenting three aspects that are essential for researchers to consider when creating models for chemical kinetics: (1) are the model’s prediction targets and associated errors sufficient for practical applications? (2) Does the model prioritize user-friendly inputs so it is practical for others to integrate into prediction workflows? (3) Does the analysis report performance on both interpolative and more challenging extrapolative data splits so users have a realistic idea of the likely errors in the model’s predictions?
Healing microstructures of experimental and natural fault gouge

[1] The healing of fault gouge was studied by examining microstructures of naturally and experimentally produced granitoid fault rock. We performed deformation experiments on intact granitoid rock samples at T = 300–500°C, Pc = 500 MPa, and = 1.2 × 10−4 – 1.3 × 10−7 s−1 with 0.2 wt% H2O added. Healing experiments were carried out on deformed samples at T = 200–500°C, Pc = 500 MPa, for 4 h to 14 days under hydrostatic and nonhydrostatic conditions. The grain size distributions (GSD) of the deformed samples were quantified using the D> value (slope of log(frequency) -log(radius) of the GSD) for quartz and feldspar fault gouge. Healing causes a decrease in the D> value from >2.0 to ∼1.5. The time dependence of the D> decrease is described by a hydrostatic healing law of the form ΔD = D>(t) − Df = A · e(−λ·t). The results of the laboratory experiments were compared to three natural fault systems, (1) Nojima Fault Zone (Japan), (2) fault zones in the Black Forest (Germany), and (3) Orobic Thrust (Italian Alps). Natural and experimental gouges have similar D> values. Healing is only observed in monomineralic aggregates; polymineralic (i.e., mixed) fault gouges retain their high D> value after extended healing times because grain growth is inhibited. Healing under nonhydrostatic conditions is more rapid than hydrostatic healing. The low strain rates, which were measured during nonhydrostatic healing, are temperature-dependent and suggest that diffusive mass transfer processes take place during deformation. Thus, fault rocks at upper to midcrustal depth may deform by combined cataclasis and diffusive mass transfer.
Cloncurry Fault Zone: strain partitioning and reactivation in a crustal-scale deformation zone, Mt Isa Inlier

The Cloncurry Fault Zone is a north-northwest-trending zone of complex deformation over 100 km long and up to 7 km wide near the eastern edge of the Mt Isa Inlier. The zone includes mylonites in an anastomosing shear-zone system with variably plunging mineral lineations within a north-northwest subvertical girdle that formed synchronously with north-northwest- and south-southeast-plunging folds. No clear overprinting of lineations in different orientations is observed, and the complexity of the penetrative fabrics can be attributed to strain partitioning during east-northeast contraction, rather than requiring a more complex history of overprinting relations. The mylonites formed at temperatures of 350–500°C, below the ∼650°C metamorphic peak that occurred during the regional D2 event, and they are superimposed on Maramungee-aged granites (1555–1545 Ma), implying that the majority of fabrics formed during D3. D3 was followed by the development of a D4 sinistral Riedel strike-slip fault system involving east-southeast contraction, which was coincident with massive Na–Ca alteration and brecciation within the zone. Reactivation with a normal component of movement occurred some time after the Jurassic. The Cloncurry Fault Zone is a crustal-scale feature of the Mt Isa inlier that records strain partitioning and a deformation history lasting over 1.5 Ga.
Geophysical signature of the Pretoria saltpan impact structure and a possible satellite crater

— The genesis of the 1.13-km-diameter Pretoria Saltpan crater has long been the focus of a controversy. Its origin has been explained by either meteorite impact or “cryptoexplosive” volcanic activity, but it was recently confirmed, through detailed petrographic and chemical analysis of a breccia layer forming part of the crater fill, that the crater was formed by impact. As the limited previous geophysical work failed to support an impact origin, a more detailed gravity and magnetic study was conducted. A possible 400-m-diameter circular crater located 3 km to the southwest of the main crater was also investigated with geophysical methods, including resistivity, seismics and ground-probing radar. The gravity signature of the main crater is compatible with that of a simple impact crater and the magnetic signature (no magnetic anomaly could be detected) rules out the possibility of a central magnetic volcanic body below the crater-fill sediments. The results for the possible twin or satellite crater are inconclusive. As it is the only such feature in the entire region, it should not be overlooked. A drilling program may reveal interesting results.
Noble gases in iddingsite from the Lafayette meteorite: Evidence for liquid water on Mars in the last few hundred million years

Abstract— We analyzed noble gases from 18 samples of weathering products (“iddingsite”) from the Lafayette meteorite. Potassium‐argon ages of 12 samples range from near zero to 670 ± 91 Ma. These ages confirm the martian origin of the iddingsite, but it is not clear whether any or all of the ages represent iddingsite formation as opposed to later alteration or incorporation of martian atmospheric 40Ar. In any case, because iddingsite formation requires liquid water, this data requires the presence of liquid water near the surface of Mars at least as recently as 1300 Ma ago, and probably as recently as 650 Ma ago. Krypton and Xe analysis of a single 34 μg sample indicates the presence of fractionated martian atmosphere within the iddingsite. This also confirms the martian origin of the iddingsite. The mechanism of incorporation could either be through interaction with liquid water during iddingsite formation or a result of shock implantation of adsorbed atmospheric gas.
Consolidation Behavior of Peats

Four peat samples, covering a wide range of fiber contents, were subjected to one-dimensional consolidation tests. The development and dissipation of excess pore water pressure, effluent outflow, and permeability were also monitored during some of the consolidation tests. The other test variables included the application of back pressure, specimen thickness, and specimen orientation. Significant compression and effluent outflow take place after the dissipation of measurable excess pore water pressure, while permeability decreases drastically during consolidation. The rate of secondary compression, after a certain time, increases with the logarithm of time before gradually decreasing until it vanishes for very large times, resulting in a new stage termed “tertiary” compression. This behavior, along with the observations of peat microstructure, supports the presence of a two-level structure for peats, possibly consisting of macropores and micropores. The rate of compression of peats depends primarily on void ratio; peat type appears to be of secondary importance. Test results provide certain insights into the nature and the mechanisms of peat consolidation. The consolidation behavior of peats is quite distinct from that of other soils and requires special considerations in laboratory testing procedures and interpretation of results.
Coupling fluvial‐hydraulic models to predict gravel transport in spatially variable flows

This study investigated spatial‐temporal variations of shear stress and bed load transport at three gravel bed river reaches of the Williams Fork River, Colorado. A two‐dimensional flow model was used to compute spatial distributions of shear stress (τ) for four discharge levels between one third of bankfull (Qbf) and Qbf. Results indicate that mean τ values are highly variable among sites. However, the properties of the mean‐normalized distributions of τ are similar across sites for all flows. The distributions of τ are then used with a transport function to compute bed load transport rates of individual grain size fractions. Probability distributions of the instantaneous unit‐width transport rates, qb, indicate that most of the bed load is transported through small portions of the bed with high τ. The mean‐normalized probability distributions of qb are different among sites for all flows except at Qbf, when the distributions overlap. We also find that the grain size distribution (GSD) of the bed load adjusts with discharge to resemble the grain size distribution of the subsurface at Qbf. We extend these results to 13 locations in the basin, using the mean‐normalized distributions of shear stress and measured subsurface grain sizes to compute bed load transport rates at Qbf. We found a remarkably similar shape of the qb distribution among sites highlighting the basin‐wide balance between flow forces and GSD at Qbf and the potential to predict sediment flux at the watershed scale.
Palaeocology and systematics of Ordovician biotas from Welsh volcaniclastic deposits

The effects of explosive volcanism on local ecosystems are investigated in Middle Ordovician siliciclastics from the Welsh Basin. Bulk sampling analysis has provided quantitative data, regarding population proportions and abundance, following ash deposition in nearshore, shallow dysaerobic basin, and deeper basinal facies. Consistent ecological effects include the destruction of small sessile benthos by rapid burial, followed by re-establishment of mobile and opportunistic taxa, and a bimodal, planktic-benthic bloom in dysaerobic facies. The results are explained through vertical circulation initiated by turbid surface waters following ash deposition. Upwelling of subsurface, nutrient-rich waters of stratified basins is accompanied by downwelling of oxygenated surface waters, entrained into broadly spaced columns. The duration and nature of the events are investigated by ecological, sedimentological, and mechanical approaches, and high sedimentation rate invoked, resulting from seismicity associated with local volcanism. Systematic studies are included on Porifera, Echinodermata and Palaeoscolecida, the unusual preservation of each resulting from volcanism-related processes. The poriferan fauna provides significant information on non-lithistid demosponges and hexactinellids, including the earliest representatives of several groups. Rapid silicification of the proteinaceous skeleton of two species indicates a new source of soft-tissue preservation. Echinoderms comprise the most diverse pre-Caradoc fauna known from Britain, including six crinoids, three asteroids, and a cystoid.