Miracle-dz/UniFAR-FTUs huggingface dataset:
Calculating unbiased tree-ring indices for the study of climatic and environmental change

In dendroclimatology, tree-ring indices are traditionally calculated as part of the tree-ring chronology development process. This is accomplished by fitting a growth curve to the ring-width series and using it as a series of expectations for more or less well specified null conditions (uniform climate perhaps) of annual radial growth. The ratio of the actual ring widths to these expectations produces a set of dimensionless indices that can be averaged arithmetically with cross-dated indices from other trees into a mean chronology suitable for studies of climatic and environmental change. We show that tree-ring indices calculated in this manner can be systematically biased. The shape of this bias is defined by the reciprocal of the growth curve used to calculate the indices, and its magnitude depends on the proximity of the growth curve to the time axis and its intercept. The underlying cause, however, is lack of fit. To avoid this bias, residuals from the growth curve, rather than ratios, can be computed. If this is done, in conjunction with appropriate transformations to stabilize the variance, the resulting tree-ring chronology will not be biased in the way that ratios can be. This bias problem is demonstrated in an annual tree-ring chronology of bristlecone pine from Campito Mountain, which has been used previously in global change studies. We show that persistent growth increase since AD 1900 in that series is over-estimated by 23.6% on average when ratios are used instead of residuals, depending on how the ring widths are transformed. Such bias in ratios is not always serious, as it depends on the joint behaviour of the growth curve and data, particularly near the ends of the data interval. Consequently, ratios can still be used safely in many situations. However, to avoid the possibility of ratio bias problems, we recommend that variance-stabilized residuals be used.
Fixed Point Results Using Implicit Mid Point Rule Iterative Process

The present work is related to the study of fixed point results via Picard-Mann iteration process of implicit midpoint rule for one nonlinear mapping. More over we shall show that Picard-Mann iteration process of implicit midpoint rule for one nonlinear mapping has same rate of convergence PicardKranoselskii iteration process of implicit midpoint rule for one nonlinear mapping. Our analytical results are supported by suitable numerical examples.
Surfactants and submicron sea spray generation

Laboratory experiments have been carried out to elucidate the role of surfactants on the primary marine aerosol production of submicron marine aerosols. A synthetic surfactant SDS was used in conjunction with artificially generated seawater, and the resultant bubble-mediated aerosol produced was observed. At 23°C, the aerosol distribution resulting from the use of surfactant-free seawater comprised three modes: (1) a dominant accumulation mode at 110 nm; (2) an Aitken mode at 45 nm; and (3) a third mode, at 300 nm, resulting from forced bursting of bubbles. The forced bursting occurs when bubbles fail to burst upon reaching the surface and are later shattered by splashing associated with breaking waves and/or wind pressure at the surface. At 4°C, the accumulation mode diameter was reduced to 85 nm, the Aitken mode diameter was reduced to <30 nm and the 300 nm mode diameter was reduced to 200 nm. With the addition of SDS, the relative importance of the mode resulting from forced bursting increased dramatically. The laboratory results were compared to the observed seasonality of North Atlantic marine aerosol where a progression from mode radii minima in winter to maxima in summer is seen. The bimodality and the seasonality in modal diameter can be mostly explained by a combination of the three modes observed in the laboratory and their variation as a function of sea-surface temperature and seawater surfactant concentration. These results indicate that submicron primary aerosol modes would on a first approximation result from bubble bursting processes, although evidences of additional secondary processes leading, during summer, to a higher amplitude of the Aitken mode and mode 2 smoothed into mode 3 still need to be investigated. Copyright 2006 by the American Geophysical Union.
Budgets of turbulent kinetic energy and scalar variance in the continental shelf bottom boundary layer

A local turbulent kinetic energy (TKE) budget, in which dissipation balances production minus buoyancy flux, and a nonlocal turbulent scalar variance (TSV) budget, in which dissipation balances production minus TSV flux divergence, are tested observationally. The calculations are based on 6 week long records of velocity and sound speed measured between 0.7 and 5.4 m above bottom on the New England shelf. Estimates of fluxes and gradients are direct, while estimates of dissipation rates are indirectly obtained from inertial subrange spectra. Within 2 m of the bottom, buoyancy flux is not an important component of the TKE budget (flux Richardson number Rf 0.8 and regression coefficient = 0.89 ×/÷ 1.06 and 1.08 ×/÷ 1.05 at 1.65 and 0.74 m above the bottom, respectively). The local TKE budget at 4.35 m above the bed is not closed, however. TSV production and dissipation estimates are strongly correlated at all heights (r2>0.64), but dissipation is systematically greater than production, particularly at 0.74 m above the bed (regression coefficient = 2.42 ×/÷ 1.28). Including TSV flux divergence in the balance reduces, statistically significantly, the observed discrepancy. The implications of the results for turbulence closure models and microstructure diffusivity estimates are discussed.
Evaluation of Ensemble Approach for O3 and PM2.5 Simulation

Inter-comparison of chemical transport models (CTMs) was conducted among four modeling research groups. Model performance of the ensemble approach to O₃ and PM 2.5 simulation was evaluated by using observational data with a time resolution of 1 or 6 hours at four sites in the Kanto area, Japan, in summer 2007. All groups applied the Community Multiscale Air Quality model. The ensemble average of the four CTMs reproduced well the temporal variation of O₃ (r=0.65-0.85) and the daily maximum O₃ concentration within a factor of 1.3. By contrast, it underestimated PM 2.5 concentrations by a factor of 1.4-2, and did not reproduce the PM 2.5 temporal variation at two suburban sites (r=~0.2). The ensemble average improved the simulation of SO₄ 2- , NO₃⁻, and NH₄⁺, whose production pathways are well known. In particular, the ensemble approach effectively simulated NO₃⁻, despite the large variability among CTMs (up to a factor of 10). However, the ensemble average did not improve the simulation of organic aerosols (OAs), underestimating their concentrations by a factor of 5. The contribution of OAs to PM 2.5 (36-39%) was large, so improvement of the OA simulation model is essential to improve the PM 2.5 simulation.
Optimal Design of DC Capacitance of Photovoltaic Self-Synchronizing Voltage Source

The self-synchronous voltage source inverter is similar in external characteristics to a synchronous generator and has an excellent performance in frequency and voltage regulation. In the scenario of grid-forming, the output power of the photovoltaic self-synchronizing voltage source is insufficient due to the inherent intermittent light disturbance, which is easy to cause DC undervoltage and even system shutdown accidents. DC capacitor energy storage can bear the output power shortage during light disturbance for a short time, provide sufficient time support for inverter output power regulation, and avoid undervoltage accidents. For this reason, this paper proposes an optimal design method of capacitance parameters based on the DC voltage transient model. This method realizes the accurate description of DC voltage fluctuations based on the inverter transient model, establishes the numerical relationship between lighting disturbance and DC voltage fluctuations under different capacitance parameters, and finally realizes the optimal design of capacitance. The simulation results show that the proposed method can provide 100-millisecond support for the inverter output power regulation during the light disturbance, effectively alleviate the DC voltage drop, and improve the DC side voltage stability of the inverter.
Drought-Driven Changes in Lake Areas and Their Effects on the Surface Energy Balance of Minnesota's Lake-Dotted Landscape

Open water within Minnesota constitutes 11 830 km 2 and represents a significant proportion of the moisture available on the landscape. Because lakes absorb and store heat in the spring and summer, and release heat in the autumn and winter, they also play a significant role in surface energy budgets. Lake areas fluctuate significantly over time, and thus alter surface albedo and energy partitioning in the expanding and contracting lake margin. Observations of lake areas from the 1930s ‘‘Dust Bowl’’ drought were used to approximate the impact of changes in lake area and volume on surface energy budgets. A statewide map of lake area change constructed from historical aerial photos of 620 lakes shows trends in percent area changes that mimic trends in moisture balance. Based on the aerial photos and an analysis of lake bathymetries, the water volume removed from the land exposed around the lakes during the drought was 9.1 6 3.0 3 10 9 m 3 . T he total area of exposed land was 3300 6 800 km 2 . Based on a balanced energy budget estimate, the transition from standing water to exposed land at lake margins accounted for 1.12 6 0.31 3 10 11 W of energy storage across the state. The decreased heat storage resulted in a statewide average storage flux anomaly of 0.50 6 0.14 W m 22 with localized anomalies as high as 33.9 6 7.1 W m 22 . Large uncertainties exist, however, regarding the partitioning of the energy because of the wide range of potential albedo values for both land and water. As conditions warmed during the twentieth century, lake volumes have increased. Therefore, the assessment herein of the change in heat storage is relevant to comparisons of high regional temperatures in the 1930s and 2000s.
The Water Balance of Pastures in a South Australian Catchment with Sloping Texture-Contrast Soils

The water use of several pasture types was compared in a catchment in the Mount Lofty Ranges, South Australia. The study sites had sloping (less than 14%) texture-contrast soils. The aim was to delineate the water pathways (e.g. evapotranspiration, surface runoff, throughflow) in the catchment and to supply farmers with the best pasture option for minimising deep drainage. Lucerne ( Medicago sativa cv. Aquarius) produced more dry matter in summer and used more water than phalaris ( Phalaris aquatica cv. Sirosa) on the mid- and upper slopes but was similar on the toe-slopes. The clay subsoils on the toe-slope were slightly saline, strongly sodic and sometimes affected by saline groundwaters in winter. After only one year’s growth, the lucerne and phalaris pastures used more water than the existing cocksfoot ( Dactylis glomerata ) pasture on all parts of the slope. TOPOG-IRM modelling indicated that on all parts of the slope there was substantial deep drainage under the existing pasture (up to 29% of annual rainfall), with much-reduced deep drainage under phalaris and lucerne.
Remotely-sensed optical and thermal indicators of land degradation.

Land degradation monitoring systems must take into account several indicators like vegetation cover, rain-use efficiency, surface run-off, soil erosion. Some of theses indicators may be derived from remote-sensing data. Estimation of vegetation cover from satellite-data relies mainly on conventional or improved vegetation indices, although evidences of better results in arid zones have been obtained from the use of spectral unmixing techniques. Estimation of vegetation condition is generally achieved through drought-related indices, obtained from a combination of NIR and SWIR data (canopy water content) or from a combination of NDVI and thermal data (health condition, dryness). NOAA-AVHRR archive data remain the reference data source for identifying temporal trends, but recently available satellite data (EOS-MODIS, MSG-SEVIRI) should give significantly improved monitoring results due to better spectral, spatial or temporal resolutions
Microbially driven acidity generation in a tailings lake

In situ characterization and geochemical modelling of acid generation in a mine tailings lake (Moose Lake, ON, Canada) over a 2‐year period (2001–2002; surficial lake pyrrhotite slurry disposal initiated in 2002) show that bacteria significantly impact acidity behaviour through particle‐associated S oxidation and that they do so under conditions that differ from those controlling abiotic pathways. Seasonal epilimnetic pH decreases occurred in both years, decreasing from approximately 3.5 in May to 2.8 by September (2001) or July (2002). Epilimnetic acid generation rates were depth‐dependent, with maximal rates observed not at the surface of lake where O2 concentrations were highest, but rather within a geochemically reactive zone (approximately 1 m thick) of steep, decreasing O2 gradients and dynamic Fe and S geochemistry in the lower epilimnetic region of the lake. Acid generation occurred dominantly through particle rather than aqueous pathways, but model predictions of acid generation via abiotic pyrrhotite oxidation involving either O2 or ferric iron (Fe3+) predicted neither the observed rates nor the depths at which maximal rates occurred. In contrast, model predictions based on microbial pathways involving both O2 and ferric iron (Fe3+) agreed extremely well with both the observed depth profile of H+ generation and the observed rates at any given depth. Imaging showed extensive microbial colonization of epilimnetic‐associated pyrrhotite particles commonly with significant biofilm formation. FISH (fluorescence in situ hybridization) probing of the community in both pelagic and particle compartments indicated mixed communities occurred in both, and that Acidithiobacillus spp. accounted for 2–46% of the total community in either compartment. Initiation of pyrrhotite slurry discharge at the lake surface in 2002 was accompanied by a relative increase in the number of particle‐associated microbes, as well as a relative proportional decrease of Acidithiobacillus spp. in the total microbial community. Given the widespread occurrence of bacteria across mining environments, the implications of our results extend beyond this specific site and provide new insight into bacterially driven processes contributing to bulk system characteristics which are not currently well constrained.
Mesozoic Troughs and Crustal Structure in Anatolia

In Anatolia, zones of ultramafic masses were emplaced during the Mesozoic into the upper crustal level. Along these zones, deep-sea troughs, characterized by radiolarite-ophiolite facies, developed within the shallow Tethys sea. After some time, the troughs were filled by mafic volcanic rocks and abyssal sediments. Thus, beneath the trenches, a change from continental to oceanic crust has taken place under crustal distension of 50 to 100 km. Later the tensional phases were followed by compression. These views are at variance with the “wide Tethys” ocean model. They are supported by the similarity of the radiolarite-ophiolite zones to other structures which are ascribed to tensional movements.
Use of 40Ar/39Ar K‐feldspar thermochronology in basin thermal history reconstruction: an example from the Big Lake Suite granites, Warburton Basin, South Australia

The potential use of 40Ar/39Ar thermochronologic data from K‐feldspars in reconstructing basin thermal history has been evaluated using the example of the Warburton/Cooper/Eromanga Basin, Australia's largest onshore oil‐ and gas‐producing basin. Results from 40Ar/39Ar step‐heating experiments reveal details of the evolution of the basin system, including the following: (1) the operation of high geothermal gradient regimes during the earliest basin evolution, suggesting that basin formation was active rather than passive; (2) slow cooling from a Permo‐Triassic temperature peak of at least 250–300°C; (3) a rise in thermal gradients to contemporary bottom hole temperatures in the last 5–10 Myr; and (4) spatially variable recrystallization events between 100 and 50 Ma and at around 20 Ma. Initial microstructural observations serve as a useful predictor of the quality and nature of the obtainable age information. Data from ‘pristine’ K‐feldspars may constrain the peak temperature conditions experienced in the basin, the basin's early thermal history and also any recent changes in thermal gradient. Contrasting data from texturally modified K‐feldspars may constrain times of thermal transients and/or fluid flow, with the preferred interpretation that K‐feldspars recrystallize in response to such events. The Warburton/Cooper/Eromanga Basin example suggests that the 40Ar/39Ar technique may serve as a useful adjunct to apatite and zircon fission track analysis and conventional organic maturation indices in basin thermal history analysis.
Chemical heterogeneity in diffusion‐dominated aquitards

High‐resolution measurements of the three‐dimensional (3‐D) variability in pore water electrical conductivity (EC) were obtained at a clay‐rich aquitard research site (the King site, 120 m × 70 m area) in southern Saskatchewan, Canada, using direct‐push probing technology (n = 35 boreholes). These measurements revealed complex lateral heterogeneity in the subsurface salt distributions which raised questions on the validity of the commonly used approach of transposing chemical data from distributed piezometers onto 1‐D depth profiles for interpretation and solute transport modeling. Two‐dimensional numerical modeling simulations demonstrated that distributed, nonuniform salt inputs have existed at the top of the unoxidized till aquitard for the past 3–5 kyr. The source of the nonuniform salt inputs is unclear but may be due to either variations in microtopography (<0.5 m) or variable penetration depth of surface fractures. A suite of generic solutions was developed to estimate the critical depth required to obtain chemical homogeneity in aquitards with nonuniform solute inputs and diffusion as the dominant transport mechanism. These solutions are presented for a range of sinusoidal input functions with varying amplitudes, magnitudes, and wavelengths. The solutions indicate EC distributions at the King site should be laterally uniform below a depth of around 20 m BG, which is consistent with observed EC values at the site. This study shows that aquitards with nonuniform salt inputs at their upper boundary are chemically heterogeneous above some critical depth and thus require careful attention when modeling solute transport processes within them.
Greenhouse Gas Emissions and Price Elasticities of Transport Fuel Demand in Belgium

Since 1990, Belgium has managed to bring down greenhouse gas emissions in most domains of economic activity. Road transport, as in many other countries, is a notable exception to this pattern: emissions have steadily increased, driven by an ever higher consumption of petrol and diesel. Even though the current overall performance will probably be sufficient to reach the reduction objectives of the Kyoto protocol, transport emissions thus need to be targeted in the future. One possible measure aimed at reducing them, an increase in fuel taxes, is examined in detail in this paper. The success of such a policy depends on the price elasticity of fuel demand, and therefore, the latter is estimated for Belgium and other European countries. The elasticities obtained are relatively small: in Belgium, for instance, a 10% increase in prices would cause consumption to fall by around 1.8% in the short-run and 2.3% in the medium run. Tax increases alone will thus certainly be insufficient for cutting emissions at this time horizon. Nevertheless, as a supporting measure in a more general reduction strategy, they could still yield substantial advantages. This Working Paper relates to the 2011 OECD Economic Review of Belgium (www.oecd.org/eco/surveys/Belgium). Emissions de gaz a effet de serre et elasticites-prix de la demande de carburants en Belgique Depuis 1990, la Belgique a reussi a reduire ses emissions de gaz a effet de serre (GES) dans la plupart des domaines d'activite economique. Comme dans de nombreux autres pays, le transport routier constitue a cet egard une exception notable : ses emissions ont regulierement augmente, sous l'effet d'une consommation toujours croissante d'essence et de gazole. Meme si les performances globales actuelles seront sans doute suffisantes pour atteindre les objectifs de reduction des emissions de GES du Protocole de Kyoto, un objectif doit donc etre defini pour les futures emissions des transports. Une des mesures envisageables pour les faire diminuer, une hausse des taxes sur les carburants, est examinee de maniere approfondie dans ce document. La reussite d'une telle mesure depend de l'elasticite-prix de la demande de carburants, ce qui nous amene a estimer celle-ci pour la Belgique et d'autres pays europeens. Les elasticites obtenues sont relativement modestes : en Belgique, par exemple, une hausse des prix de 10 % entrainerait un recul de la consommation de l'ordre de 1.8 % a court terme, et de 2.3 % a moyen terme. De simples augmentations des taxes seront donc certainement insuffisantes pour reduire les emissions a cet horizon. Neanmoins, en tant que mesures d'accompagnement s'inscrivant dans le cadre d'une strategie plus generale de reduction des emissions de GES, elles pourraient avoir des retombees positives substantielles. Ce Document de travail se rapporte a l’Etude economique de l’OCDE de la Belgique 2011 (www.oecd.org/eco/etudes/Belgique).
Prevalence and correlates of mental disorders among Native American women in primary care.

OBJECTIVES We examined the lifetime and the past-year prevalence and correlates of common mental disorders among American Indian and Alaska Native women who presented for primary care. METHODS We screened 489 consecutively presenting female primary care patients aged 18 through 45 years with the General Health Questionnaire, 12-item version. A subsample (n = 234) completed the Composite International Diagnostic Interview. We examined associations between psychiatric disorders and sociodemographic variables, boarding school attendance, and psychopathology in the family of origin. RESULTS The study participants had high rates of alcohol use disorders, anxiety disorders, and anxiety/depression comorbidity compared with other samples of non-American Indian/Alaska Native women in primary care settings. CONCLUSIONS There is a need for culturally appropriate mental health treatments and preventive services.