Miracle-dz/UniFAR-FTUs huggingface dataset:
Soil nitrogen mineralisation and organic matter composition revealed by 13C NMR spectroscopy under repeated prescribed burning in eucalypt forests of south-east Queensland

The effects of burning on in situ extractable nitrogen (NH+4-N+NO-3-N) and net Nmineralisation following scheduled fuel reduction burns in repeatedly burnt dry and wet sclerophyll forest sites in south-east Queensland were assessed. In addition, soil organic matter composition in the wet sclerophyll site was assessed by 13C NMR spectroscopy. The results showed that at the dry sclerophyll site, extractable N and net N mineralisation for 1 year were largely unaffected by burning, while at the wet sclerophyll site, these parameters decreased. 13C NMR analysis of soil samples from the wet sclerophyll site revealed that there was a significant reduction in the proportion of O-alkyl (alkoxy/carbohydrate) C with increasing burning frequency. Statistically significant effects on the other chemical shift regions were not detected. The ratio of alkyl C to O-alkyl C, a proposed index of organic matter decomposition, increased with increasing burning frequency. A high ratio of alkyl C to O-alkyl C suggests low amounts of carbohydrates relative to waxes and cutins, which could in turn lead to slower mineralisation. The findings are in accord with this hypothesis. There were significant linear relationships between cumulative N mineralisation for 1 year and the proportions of alkyl C and O-alkyl C, and the ratio of alkyl C/O-alkyl C. Thus, in addition to reductions in substrate quantity (low organic C and total N for burnt soils), there was also an alteration of substrate quality as revealed by 13C NMR spectroscopy which is reflected in low N mineralisation.
Predictive Formulas for Breaker Depth Index and Breaker Type

Abstract This study was undertaken to establish the most reliable breaker depth index formula that will yield satisfactory predictions for a wide range of hydraulic and beach conditions. The applicability of six existing formulas for computing the breaker depth index was examined with the use of a large amount of published laboratory data (524 cases collected from 22 sources). The behavior of these formulas was studied with respect to the main governing parameters, which are the beach slope and the deep-water wave steepness. It was found that most formulas show quite good predictions for cases including gentle slopes (0.01 < m ≤ 0.07). However, the predictions are typically not satisfactory for breaking waves on steep slopes (m > 0.1), and the formulas do not always present a physically correct behavior with respect to the two main parameters. A new formula is proposed to predict the breaker depth index with the best possible accuracy. Also, a discussion is included on the application of the formula to random waves and on the relationship between the breaker depth index and the Irribaren number to distinguish between different breaker types.
Variability of precipitation over the coastal western Antarctic Peninsula from synoptic observations

Observations of precipitation events at Faraday and Rothera Stations are analyzed to investigate the spatial and temporal variability of precipitation along the western coastal (Pacific) side of the Antarctic Peninsula. The record of observations made at Faraday since 1956 show a statistically significant increase in the number of winter-season precipitation events. During this season, there are now, on the average, almost 50% more reports of precipitation than during the 1950s. On a year-to-year basis the number of precipitation events is not correlated with the mean surface temperature on the western side of the Antarctic Peninsula but is dependent on synoptic weather system activity. The annual total number of precipitation events at Rothera is also increasing, but because the length of the record is relatively short, this is not statistically significant. The semiannual cycle in the latitudinal location and depth and position of the circumpolar trough is reproduced in the record of precipitation events at both Faraday and Rothera. It is argued that the systematic increase in the number of precipitation events at Faraday since the 1950s is associated with changes in the depression tracks across the Bellingshausen Sea, with an increase in the number of depressions approaching from outside the Antarctic rather than from the west.
The linking of plate tectonics and evolutionary divergences (Reply to Bauzà-Ribot et al .)

It is exciting to be living at a time when some of the big questions in biology can be investigated using great advances in genetics and computing [1]. Bauzà-Ribot et al . [2] take on one of the fundamental drivers of biodiversity on our planet, the effect of continental drift in the formation of the world’s biota [3, 4], employing a combination of whole mitochondrial genomes from next-generation sequencing and modern Bayesian relaxed molecular clock analysis. Bauzà-Ribot et al . [2] conclude that vicariance via plate tectonics best explains the genetic divergence between subterranean metacrangonyctid amphipods currently found on islands separated by the Atlantic Ocean. This finding is a big deal in biogeography, and science generally [3], since many other presumed biotic tectonic divergences have been explained as probably due to more recent transoceanic dispersal events [4]. However, molecular clocks can be problematic at the best of times [5, 6] and we have identified three issues with the analyses of Bauzà-Ribot et al . [2], that cast serious doubts on their results and subsequent conclusions. When we reanalyzed their mitochondrial data and attempted to account for problems with calibration [5, 6], modeling rates across branches [5, 7] and substitution saturation [5], we inferred a much younger date for their key node. This implies either a later trans-Atlantic dispersal of these crustaceans, or more likely a series of later invasions of freshwaters from a common marine ancestor, but either way probably not the result of ancient tectonic plate movements, thus highlighting pertinent issues for all practitioners of evolutionary dating studies. Bauzà-Ribot
Holocene climatic and human influences on lakes of the Yucatan Peninsula, Mexico: an interdisciplinary, palaeolimnological approach

We used palaeolimnological techniques to examine effects of Holocene climate change and human influence on lakes of the Yucatan Peninsula, Mexico. The three study lakes are located along a west-east transect that represents a gradient of increasing modern precipitation and density of former Maya settlement. At Lake Coba, an 880-cm sediment core yields a complete record of lacustrine sedimentation that began when the lake first filled ∼8000 BP as groundwater level rose in response to rising sea level and increased precipi tation. Diatom, ostracod, and δ 18O evidence indicate that Lake Coba was initially shallow and saline. Coba, presently in the region of greatest rainfall, showed more episodic water-level changes than Lake San Jose Chulchaca or Lake Sayaucil. High lake level and fresh water were evident at 440 cm (∼2600 BP), followed by a decline in water levels and an increase in total ionic salinity to the present time. In a 613-cm core from Sayaucil, in the intermediate precipitation zone, total salinity was high between 600 and 400 cm (∼3050 and 2000 BP), followed by consistently higher water levels. Salinity was high in the lower portion of a 110-cm San Jose Chulchaca core (beginning ∼1860 BP), followed by a gradual and consistent freshening of water to the present time. Trophic state changes and human influence on lakes were evaluated using diatom, δ13C, total P, sedimentary organic matter, and preliminary pollen data. Maximal human disturbance at Lake Coba, a densely settled Maya urban site, occurred during a deep-water event at 440 cm, followed by a decline in human influence and trophic state to the present time. Trophic state and linear sedimentation rates in Sayaucil increased significantly above 400 cm (after ∼2000 BP), probably associated with initial Maya settlement near Xtojil and subsequent small- scale farming. Limnological disturbance may have preceded the period of maximal human occupation because initial land clearance and consequent soil erosion probably affected water quality substantially. San Jose Chul chaca lacks archaeological evidence of human occupation in the drainage, and shows gradual changes in trophic state not caused by human disturbance. With the exception of a 14C date on wood from the base of the Coba core, 14C dates and chronologies may be artificially old as a consequence of hard-water-lake error. Trophic state changes in the study lakes were generally consistent with known patterns of human settlement and popu lation change. Late-Holocene water-level fluctuations were most pronounced in Lake Coba in eastern Yucatan, where modern rainfall is currently greatest, but lake level is generally lower than during much of the past. Lake level was relatively constant in Sayaucil in the central peninsula, whereas lake level in San Jose Chulchaca in the arid western portion of the peninsula increased gradually over time.
Pollution atmosphérique et santé : évaluation monétaire et effets de long terme

La pollution de l'air et ses effets sur la sante sont devenues l'une des preoccupations environnementales majeures. Ce travail reprend les resultats d'une etude pluridisciplinaire menee sous l'egide de l'Organisation Mondiale de la Sante a l'initiative d'agences gouvernementales autrichiennes, francaises et suisses qui a permis d'evaluer les couts externes de ces effets sanitaires.
Geothermometry and geobarometry: a discussion

Geothermometric and geobarometric methods are considered under two groupings: directly calibrated methods and internally consistent data set methods. Emphasis is placed on the importance of error propagation calculations. They allow the calculation of model uncertainties on temperatures and pressures due to the quantifiable uncertainties involved in the calibration and application of methods. The possibility of systematic errors, due to the unquantifiable effects of the assumptions and approximations involved, must be evaluated using the criterion of geological reasonableness. The advantages of the internally consistent data set approach are expounded and an appropriate error propagation procedure developed.
Predicting Longitudinal Dispersion Coefficient in Natural Streams

In this study, previous empirical equations used to compute the dispersion coefficient are analyzed in order to evaluate their behavior in predicting dispersion characteristics in natural streams. A comparative analysis of previous theoretical and empirical equations is reported. A new simplified method for predicting dispersion coefficients using hydraulic and geometric data that are easily obtained in natural streams is also developed. The one-step Huber method, which is one of the nonlinear multiregression methods, is applied to derive a new dispersion coefficient equation. This equation is proven to be superior in explaining dispersion characteristics of natural streams more precisely, as compared to existing equations.
BRONZE AGE CHILDHOOD MIGRATION OF INDIVIDUALS NEAR STONEHENGE, REVEALED BY STRONTIUM AND OXYGEN ISOTOPE TOOTH ENAMEL ANALYSIS*

Contrasting lifestyles are recorded by the isotope composition of Bronze Age Beaker people (c. 2500–2000 bc) from three burial sites (Boscombe Down, Normanton Down and the ditch around Stonehenge) at or near to the Stonehenge monument in Wiltshire, southern England. Seven individuals (three adults, a sub-adult, two juveniles and an infant) were recovered from a single grave at Boscombe Down. Strontium and oxygen isotope analysis of tooth enamel from two teeth (a premolar and third molar) from each of three of the adults in this grave (referred to as Boscombe Bowmen) show that they had all shared a pattern of mobility and migration during their lives. The three adult males spent their early childhood (as represented by data from the premolar teeth) in an area with a radiogenic 87Sr/86Sr isotope signature of around 0.7135. They each then moved, during early adolescence (as represented by the third molar results), to a less radiogenic area, where they acquired an 87Sr/86Sr signature of around 0.7112. This implies that they must then have travelled to the Stonehenge area of Wiltshire at a later time in their lives. Wales provides the closest area with rocks that supply suitable 87Sr/86Sr ratios and δ18O isotope compositions for these individuals, although other areas of Palaeozoic rock, such as Scotland and parts of Europe, cannot be ruled out. Enamel from the two juveniles from the Boscombe Down burial yields 87Sr/86Sr ratios of 0.7098 and 0.7099, and strontium concentrations for both of 55 ppm. The very close match of the data for the two juveniles supports the possibility that they were raised in the same environment. The difference in strontium isotope data between the juveniles and three adult males described above shows that the children did not come from the same homeland as the adults with whom they share a grave. The two adult males from the single burials at Normanton Down, and from Stonehenge itself, had static lifestyles and show no evidence of migration, in contrast to the Boscombe Bowmen. Their oxygen and strontium data are consistent with a childhood in the Stonehenge area.
Mass balance of Greenland's three largest outlet glaciers, 2000–2010

Acceleration of Greenland's three largest outlet glaciers, Helheim, Kangerdlugssuaq and Jakobshavn Isbræ, accounted for a substantial portion of the ice sheet's mass loss over the past decade. Rapid changes in their discharge, however, make their cumulative mass‐change uncertain. We derive monthly mass balance rates and cumulative balance from discharge and surface mass balance (SMB) rates for these glaciers from 2000 through 2010. Despite the dramatic changes observed at Helheim, the glacier gained mass over the period, due primarily to the short‐duration of acceleration and a likely longer‐term positive balance. In contrast, Jakobshavn Isbræ lost an equivalent of over 11 times the average annual SMB and loss continues to accelerate. Kangerdlugssuaq lost over 7 times its annual average SMB, but loss has returned to the 2000 rate. These differences point to contrasts in the long‐term evolution of these glaciers and the danger in basing predictions on extrapolations of recent changes.
Preservation of the rescaled adjusted range: 2. Simulation studies using Box‐Jenkins Models

It is demonstrated that autoregressive moving average (Arma) models do preserve the rescaled adjusted range (RAR) or equivalently the Hurst coefficient K. Arma models are fit to 23 geophysical time series, and by using Monte Carlo techniques and a specified statistical test it is shown that the observed RAR or K is retained by the models. The empirical cumulative distribution function (ECDF) for these statistics can be calculated as closely as is required to the theoretical distribution. Furthermore, the distribution of the RAR is a function of the time series length N and the parameter values of the particular Arma process being considered. Various estimates for the Hurst coefficient are compared for the 23 geophysical data sets. The appendix is available with entire article on microfiche. Order from American Geophysical Union, 1909 K Street, N.W. , Washington, D.C. 20006. Document W78-003; $1.00. Payment must accompany order.
Triamcinolone acetonide loaded-cationic nano-lipoidal formulation for uveitis

Topical administration of corticosteroids is the cornerstone treatment of anterior uveitis, but poor corneal penetration and retention cause hindrance in their therapeutic utility. The conventional eye drops are less valuable in conditions where inflammation reaches deeper regions of the eye. Therefore, there is a clear need for an effective drug delivery system, which can increase corticosteroid penetration after topical application. To address this, cationic nanostructured lipid carriers of the drug triamcinolone acetonide (cTA-NLC) were prepared. The cTA-NLC were prepared by a hot microemulsion method and evaluated for drug release, permeation, cell uptake, cytotoxicity, anti-inflammatory activity and ocular irritancy. The cTA-NLC are nanometric in size (< 200 nm), with a zeta potential of about +35 mv and % drug EE of 88%. The nanocarriers exhibited slow and sustained release of around 84% in 24 h and transcorneal drug permeation of 51% in 8 h. The nanocarriers exhibited no cytotoxicity (% cell viability of >90%). The cell uptake study showed that nanocarriers could retain inside the cells for 24 h. The developed formulation could significantly reduce the TNF- α level in LPS induced inflamed cells. The studies indicated that cTA-NLC could be a promising option for the topical treatment of uveitis. 24.68° and 26.92°. The blank NLC show their characteristic peaks at 2 θ positions of 5.39°, 10.78°, 18.78°, 19.28°, 19.65°, 20.01°, 20.42°, 20.91° and 23.65°, 16°. In the XRD spectra of cTA-NLC, most of the peaks of blank NLC have reappeared, with a slight shift at 2 θ positions of
Multiyear aerosol observations with dual‐wavelength Raman lidar in the framework of EARLINET

[1] For the first time, a Raman lidar operating simultaneously in the ultraviolet (UV) and in the visible wavelength range was employed to measure vertical profiles of volume extinction coefficients of particles at 355 and 532 nm, the respective Angstrom exponent, and the 355–nm and 532–nm extinction–to–backscatter ratio (lidar ratio) on a routine basis for several years. The long–term observations were performed at Leipzig (52°N, 12°E), Germany, in the framework of the European Aerosol Research Lidar Network (EARLINET) project from May 2000 to March 2003. The lidar data were acquired under nighttime conditions. The main findings describe the mean optical properties of central European haze (anthropogenic particles) and can be summarized as follows. The 3-year mean, planetary boundary layer (PBL) extinction coefficients were 191 Mm−1 at 355 nm and 94 Mm−1 at 532 nm. The respective mean Angstrom exponent (for the 355–532–nm wavelength range) was 1.4 in the upper PBL (above 1000 m). The PBL stretched, on average, to heights of 1300 m (winter) and 2350 m (summer). PBL mean particle optical depths were 0.38 (355 nm, ±0.23 standard deviation) and 0.18 (532 nm, ±0.11 standard deviation). Free tropospheric particles contributed 2% (clean free troposphere) to 88% (major Saharan dust events) to the tropospheric optical depth. The average was 17% (355 nm) and 22% (532 nm) in 2000–2003. Angstrom exponents in the free troposphere of about one reflect the dominant influence of Saharan dust and aged smoke on the optical properties in this height range. Three-year mean lidar ratios of 58 sr (355 nm) and 53 sr (532 nm) were found in the upper part of the PBL. Free tropospheric lidar ratios were on average 52 sr (355 nm) and 53 sr (532 nm). From combined observations with the Aerosol Robotic Network (AERONET) Sun photometer and the EARLINET lidar, extinction–to–backscatter ratios at 1064 nm were estimated to be, on average, 45 sr. A comparison with optical measurements made at the Leipzig University from 1990 to 1994 indicates that the PBL extinction coefficient at 532 nm decreased by a factor of about 2 (summer half year) to almost 5 (winter season) since the unification of Germany (1990), mainly caused by the industrial breakdown in eastern Germany in the early 1990s.
Early Cambrian priapulid worms buried with their lined burrows

Five specimens of the priapulid Maotianshania cylindrica preserved inside their lined burrows were described from the Lower Cambrian Chengjiang deposits near Kunming, southern China. The exceptional preservation suggests that this worm made a dwelling tube by lining within the uppermost sediment layers. This seems to be unique among priapulids in comparison with the Cambrian Selkirkia and Paraselkirkia, as well as some modern priapulid larvae and loriciferans. Taphonomic evidence indicates that the burrow-and-worm specimens are not buried in situ but were moved by storm, tsunami, or turbidity generated currents that are thought to have brought sedimentary material intermittently.
Isotopic and nutritional evidence for species‐ and site‐specific responses to N deposition and elevated CO2 in temperate forests

In this study we show that the effect of rising atmospheric CO2 levels on forest productivity is influenced by changes in nutrient availability caused by nitrogen (N) deposition. We used a dual‐isotope approach (δ15N and δ13C), combined with dendrochronological and nutritional analyses, to evaluate the response of two dominant tree species in natural forest ecosystems near Mexico City (Pinus hartwegii—pine; Abies religiosa—fir). Our analysis focuses on changes that occurred over the past 50 years at two sites, one under high and one under low N deposition rates. Analyses of carbon isotope composition indicate increasing water‐use efficiency in response to rising CO2 levels for both species and sites but this effect did not lead to improved tree growth. The magnitude and direction of shifts in 13C discrimination indicate a process of acclimation that varied with the rate of N deposition and species traits. Since the 1960s, strong negative responses to N deposition have been observed in fir trees, which showed altered foliar nutrition and growth decline, while the negative impacts of N deposition on pine trees remained undetectable until the 1990s. In recent years, both species have shown significant growth decline under high N deposition despite increasing atmospheric CO2. Multivariate analysis of leaf nutrients indicates that growth decline was prompted by depleted soil macronutrient (P, K, and Ca) and micronutrient (Cu, Fe, Zn, and Mn) availability. At both sites, fir trees were a better indicator of N deposition due to differences in canopy rainfall interception.
Constraints on the utility of MnO2 cartridge method for the extraction of radionuclides: A case study using 234Th

Large volume (102–103 L) seawater samples are routinely processed to investigate the partitioning of particle reactive radionuclides and Ra between solution and size‐fractionated suspended particulate matter. One of the most frequently used methods to preconcentrate these nuclides from such large volumes involves extraction onto three filter cartridges (a prefilter for particulate species and two MnO2‐coated filters for dissolved species) connected in series. This method assumes that the extraction efficiency is uniform for both MnO2‐coated cartridges, that no dissolved species are removed by the prefilter, and that any adsorbed radionuclides are not desorbed from the MnO2‐coated cartridges during filtration. In this study, we utilized 234Th‐spiked coastal seawater and deionized water to address the removal of dissolved Th onto prefilters and MnO2‐coated filter cartridges. Experimental results provide the first data that indicate (1) a small fraction of dissolved Th (<6%) can be removed by the prefilter cartridge; (2) a small fraction of dissolved Th (<5%) retained by the MnO2 surface can also be desorbed, which undermines the assumption of uniform extraction efficiency for Th; and (3) the absolute and relative extraction efficiencies can vary widely. These experiments provide insight on the variability of the extraction efficiency of MnO2‐coated filter cartridges by comparing the relative and absolute efficiencies and recommend the use of a constant efficiency on the combined activity from two filter cartridges connected in series for future studies of dissolved 234Th and other radionuclides in natural waters using sequential filtration/extraction methods.