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Nowadays, full-waveform inversion, based on fitting the measured surface data with modelled data, has become the preferred approach to recover detailed physical parameters from the subsurface. However, its application is computationally expensive for large inversion domains. Furthermore, when the subsurface has a complex geological setting, the inversion process requires an appropriate pre-conditioning scheme to retrieve the medium parameters for the desired target area in a reliable manner. One way of dealing with both aspects is by waveform inversion schemes in a target-oriented fashion. Therefore, we propose a prospective application of the convolution-type representation for the acoustic wavefield in the frequency–space domain formulated as a target-oriented waveform inversion method. Our approach aims at matching the observed and modelled upgoing wavefields at a target depth level in the subsurface, where the seismic wavefields, generated by sources distributed above this level, are available. The forward modelling is performed by combining the convolution-type representation for the acoustic wavefield with solving the two-way acoustic wave-equation in the frequency–space domain for the target area. We evaluate the effectiveness of our inversion method by comparing it with the full-domain full-waveform inversion process through some numerical examples using synthetic data from a horizontal well acquisition geometry, where the sources are located at the surface and the receivers are located along a horizontal well at the target level. Our proposed inversion method requires less computational effort and, for this particular acquisition, it has proven to provide more accurate estimates of the target zone below a complex overburden compared to both full-domain full-waveform inversion process and local full-waveform inversion after applying interferometry by multidimensional deconvolution to get local-impulse responses.

We calculate optimal age-dependent labor income taxes in an environment for which the age efficiency profile is endogenously determined by human capital investment. Heterogeneous individuals are exposed to idiosyncratic shocks to their human capital investments, a key element, along with the endogeneity of human capital itself in the determination of optimal age-dependent taxes. Our results highlight the complementary role of capital income taxation when human capital is endogenous. The nature of human capital accumulation is quantitatively relevant for determining the age dependence of income taxes. We assess the cost of ignoring the endogenous nature of age-efficiency profiles.

Why do some forests produce biomass more efficiently than others? Variations in Carbon Use Efficiency (CUE: total Net Primary Production (NPP)/ Gross Primary Production (GPP)) may be due to changes in wood residence time (Biomass/NPPwood), temperature, or soil nutrient status. We tested these hypotheses in 14, one ha plots across Amazonian and Andean forests where we measured most key components of net primary production (NPP: wood, fine roots, and leaves) and autotrophic respiration (Ra; wood, rhizosphere, and leaf respiration). We found that lower fertility sites were less efficient at producing biomass and had higher rhizosphere respiration, indicating increased carbon allocation to belowground components. We then compared wood respiration to wood growth and rhizosphere respiration to fine root growth and found that forests with residence times 40 yrs. A comparison of rhizosphere respiration to fine root growth showed that rhizosphere growth respiration was significantly greater at low fertility sites. Overall, we found that Amazonian forests produce biomass less efficiently in stands with residence times >40 yrs and in stands with lower fertility, but changes to long-term mean annual temperatures do not impact CUE.

Transpiration from the Amazon rainforest generates an essential water source at a global and local scale. However, changes in rainforest function with climate change can disrupt this process, causing significant reductions in precipitation across Amazonia, and potentially at a global scale. We report the only study of forest transpiration following a long-term (>10 year) experimental drought treatment in Amazonian forest. After 15 years of receiving half the normal rainfall, drought-related tree mortality caused total forest transpiration to decrease by 30%. However, the surviving droughted trees maintained or increased transpiration because of reduced competition for water and increased light availability, which is consistent with increased growth rates. Consequently, the amount of water supplied as rainfall reaching the soil and directly recycled as transpiration increased to 100%. This value was 25% greater than for adjacent non-droughted forest. If these drought conditions were accompanied by a modest increase in temperature (e.g. 1.5°C), water demand would exceed supply, making the forest more prone to increased tree mortality. This article is protected by copyright. All rights reserved.

Understanding the relationship between photosynthesis, net primary productivity and growth in forest ecosystems is key to understanding how these ecosystems will respond to global anthropogenic change, yet the linkages among these components are rarely explored in detail. We provide the first comprehensive description of the productivity, respiration and carbon allocation of contrasting lowland Amazonian forests spanning gradients in seasonal water deficit and soil fertility. Using the largest data set assembled to date, ten sites in three countries all studied with a standardized methodology, we find that (i) gross primary productivity (GPP) has a simple relationship with seasonal water deficit, but that (ii) site-to-site variations in GPP have little power in explaining site-to-site spatial variations in net primary productivity (NPP) or growth because of concomitant changes in carbon use efficiency (CUE), and conversely, the woody growth rate of a tropical forest is a very poor proxy for its productivity. Moreover, (iii) spatial patterns of biomass are much more driven by patterns of residence times (i.e. tree mortality rates) than by spatial variation in productivity or tree growth. Current theory and models of tropical forest carbon cycling under projected scenarios of global atmospheric change can benefit from advancing beyond a focus on GPP. By improving our understanding of poorly understood processes such as CUE, NPP allocation and biomass turnover times, we can provide more complete and mechanistic approaches to linking climate and tropical forest carbon cycling.

Matheus TCU, Menezes WMM, Rigo OD, Kabayama LK, Viana CSC, Otubo J. The influence of carbon content on cyclic fatigue of NiTi SMA wires. International Endodontic Journal, 44, 567–573, 2011. Abstract Aim To evaluate two NiTi wires with different carbon and oxygen contents in terms of mechanical resistance to rotary bending fatigue (RBF) under varied parameters of strain amplitude and rotational speed. Methodology The wires produced from two vacuum induction melting (VIM) processed NiTi ingots were tested, Ti-49.81at%Ni and Ti-50.33at%Ni, named VIM 1 and VIM 2. A brief analysis related to wire fabrication is also presented, as well as chemical and microstructural analysis by energy dispersive spectroscopy (EDS) and optical microscope, respectively. A computer controlled RBF machine was specially constructed for the tests. Three radii of curvature were used: 50.0, 62.5 and 75.0 mm, respectively, R1, R2 and R3, resulting in three strain amplitudes ea: 1.00%, 0.80% and 0.67%. The selected rotational speeds were 250 and 455 rpm. Results The VIM 1 wire had a high carbon content of 0.188 wt% and a low oxygen content of 0.036 wt%. The oxygen and carbon contents of wire VIM 2 did not exceed their maximum, of 0.070 and 0.050 wt%, according to ASTM standard (ASTM F-2063-00 2001). The wire with lower carbon content performed better when compared to the one with higher carbon content, withstanding 29 441 and 12 895 cycles, respectively, to fracture. Conclusions The surface quality of the wire was associated with resistance to cyclic fatigue. Surface defects acted as stress concentrators points. Overall, the number of cycles to failure was higher for VIM 2 wires with lower carbon content.

Inhalation of the local anaesthetic lidocaine has been suggested to be beneficial for asthmatics, but airway anaesthesia is unpleasant and may exacerbate bronchoconstriction. Our previous study showed that inhalation of the lidocaine analogue JMF2-1 can elicit the anti-inflammatory properties of lidocaine without anaesthesia. This prompted further research on the mechanism of action and putative therapeutic application of JMF2-1.

P>1. The Amazon region may experience increasing moisture limitation over this century. Leaf dark respiration (R) is a key component of the Amazon rain forest carbon (C) cycle, but relatively little is known about its sensitivity to drought. 2. Here, we present measurements of R standardized to 25 degrees C and leaf morphology from different canopy heights over 5 years at a rain forest subject to a large-scale through-fall reduction (TFR) experiment, and nearby, unmodified Control forest, at the Caxiuana reserve in the eastern Amazon. 3. In all five post-treatment measurement campaigns, mean R at 25 degrees C was elevated in the TFR forest compared to the Control forest experiencing normal rainfall. After 5 years of the TFR treatment, R per unit leaf area and mass had increased by 65% and 42%, respectively, relative to pre-treatment means. In contrast, leaf area index (L) in the TFR forest was consistently lower than the Control, falling by 23% compared to the pre-treatment mean, largely because of a decline in specific leaf area (S). 4. The consistent and significant effects of the TFR treatment on R, L and S suggest that severe drought events in the Amazon, of the kind that may occur more frequently in future, could cause a substantial increase in canopy carbon dioxide emissions from this ecosystem to the atmosphere.

Despite the importance of the gastronomic experience for tourists' satisfaction/dissatisfaction, and hence for the competitiveness of tourist des- tinations, studies focusing on tourists' satisfaction with their gastronomic experience are virtually non-existent. More importantly, researchers have not yet produced evidence to support a factor structure of gastronomy satisfac- tion. The purpose of this paper is, therefore, to investigate the presence of a single second-order factor by developing and empirically validating a second- order factor analysis model for measuring satisfaction of gastronomic tourists in Portugal. As theorized, satisfaction comprised distinct first-order factors and a single second-order factor. The results suggest that gastronomy satis- faction in a tourism setting is a multidimensional construct comprising three factors: 'gastronomy', 'price and quality' and 'atmosphere'. Among these three first-order factors, 'gastronomy' was the most important determinant of tourist satisfaction, followed by 'price and quality' and 'atmosphere'.

In the next few decades, climate of the Amazon basin is expected to change, as a result of deforestation and rising temperatures, which may lead to feedback mechanisms in carbon (C) cycling that are presently unknown. Here, we report how a throughfall exclusion (TFE) experiment affected soil carbon dioxide (CO2) production in a deeply weathered sandy Oxisol of Caxiuana (Eastern Amazon). Over the course of 2 years, we measured soil CO2 efflux and soil CO2 concentrations, soil temperature and moisture in pits down to 3 m depth. Over a period of 2 years, TFE reduced on average soil CO2 efflux from 4.3±0.1 μmol CO2 m−2 s−1 (control) to 3.2±0.1 μmol CO2 m−2 s−1 (TFE). The contribution of the subsoil (below 0.5 m depth) to the total soil CO2 production was higher in the TFE plot (28%) compared with the control plot (17%), and it did not differ between years. We distinguished three phases of drying after the TFE was started. The first phase was characterized by a translocation of water uptake (and accompanying root activity) to deeper layers and not enough water stress to affect microbial activity and/or total root respiration. During the second phase a reduction in total soil CO2 efflux in the TFE plot was related to a reduction of soil and litter decomposers activity. The third phase of drying, characterized by a continuing decrease in soil CO2 production was dominated by a water stress-induced decrease in total root respiration. Our results contrast to results of a drought experiment on clay Oxisols, which may be related to differences in soil water retention characteristics and depth of rooting zone. These results show that large differences exist in drought sensitivity among Amazonian forest ecosystems, which primarily seem to be affected by the combined effects of texture (affecting water holding capacity) and depth of rooting zone.

Climate modelling studies predict that the rain forests of the Eastern Amazon basin are likely to experience reduc- tions in rainfall of up to 50% over the next 50-100 years. Efforts to predict the effects of changing climate, especially drought stress, on forest gas exchange are currently limited by uncertainty about the mechanism that controls stomatal closure in response to low soil moisture. At a through-fall exclusion experiment in Eastern Amazonia where water was experimentally excluded from the soil, we tested the hypothesis that plants are isohydric, that is, when water is scarce, the stomata act to prevent leaf water potential from dropping below a critical threshold level. We made diurnal measurements of leaf water potential ( Ψ l ), stomatal con- ductance ( g s ), sap flow and stem water potential ( Ψ stem ) in the wet and dry seasons. We compared the data with the predictions of the soil-plant-atmosphere (SPA) model, which embeds the isohydric hypothesis within its stomatal conductance algorithm. The model inputs for meteorology, leaf area index (LAI), soil water potential and soil-to-leaf hydraulic resistance ( R ) were altered between seasons in accordance with measured values. No optimization param- eters were used to adjust the model. This 'mechanistic' model of stomatal function was able to explain the individ- ual tree-level seasonal changes in water relations ( r 2 = 0.85, 0.90 and 0.58 for Ψ l , sap flow and g s , respectively). The model indicated that the measured increase in R was the dominant cause of restricted water use during the dry sea- son, resulting in a modelled restriction of sap flow four times greater than that caused by reduced soil water poten- tial. Higher resistance during the dry season resulted from an increase in below-ground resistance (including root and soil-to-root resistance) to water flow.

High quality Molecular Sieve Silica (MSS) membranes in scaled up tubes were tested for the permeation of single gases and synthetic reformate (H2, CO2, CO) for fuel cells at temperatures up to 250°C and up to 2 bar pressure difference across the membrane. The flux of gases increased as a function of temperature, indicating activated transport, a characteristic of molecular sieving materials. H2/CO selectivities of 12.6 and H2 permeation of 3x10-9 mol.m-2.s-1.Pa-1 were achieved. Reformate clean up resulted in CO concentrations as low as 169 ppmv, which is very close to levels acceptable for CO tolerant PEM fuel cells. Pressure changes across the membrane did not affect the permeation of single gases. Helium gas permeation slightly decayed at a rate of 7.7x10-11 mol.m-2.s- 1.Pa-1 per day for a 36 days testing period. Temperature cyclic testing (heating and cooling) did not affect the membrane performance.

We report two patients with Beare-Stevenson syndrome. This syndrome presents craniosynostosis with or without clover-leaf skull, craniofacial anomalies, cutis gyrata, acanthosis nigricans, prominent umbilical stump, furrowed palms and soles, genital and anal anomalies. Both female newborn patients presented at birth with craniofacial anomalies, variable cutis gyrata in forehead and preauricular regions, prominent umbilical stump and anogenital anomalies. Furrowed palms and soles were also observed. The radiologic examination showed a cloverleaf-form craniosynostosis. Chromosomes were normal. They were born with respiratory distress and were connected to mechanical ventilation for ventilatory support. Both of them died in 50 days after birth due to secondary complications. The molecular analysis of these patients identified the mutation Tyr375Cys in the FGFR2 gene.

Background Leishmaniasis is endemic in 88 countries in the world, and 350 million individuals are at risk of acquiring the disease. Treatment for American cutaneous leishmaniasis (ACL) is long, expensive, and associated with important side-effects. Methods In this double-blind, placebo-controlled study, we treated 102 patients with ACL using either a combination of a single-strain Leishmania amazonensis killed promastigote vaccine plus a half dose of meglumine antimoniate, or placebo plus the same half dose regimen of meglumine antimoniate, in 10-day series followed by 10-day intervals. Results Of the 47 patients in the experimental arm, 47 (100%) were cured after four series of treatment, compared to four of 49 (8.2%) in the control group (P < 0.0001). Six patients were lost to follow-up. Conclusions The combination of a single-strain Leishmania (Leishmania) amazonensis killed promastigote vaccine with a half dose regimen of antimonial is highly effective for the treatment of ACL.

Compound 1c, a synthetic derivative of lapachol (1a), was synthesized in 37% overall yield from safrole (2).

Reduction of (Z)-β-butyltelluro-enones gives the corresponding γ-hydroxy vinylic tellurides with retention of the double bond configuration. Reaction of γ-hydroxy vinylic tellurides with 2 equiv of n-butyllithium produces 1,4-C,O-dianions, which on reaction with carbon dioxide give the corresponding butenolides.

Some heteroaromatic esters were reduced to the corresponding alcohols by using a sodium borohydride–methanol system. The reduction was completed within 0.15–2.0 h in refluxing THF. The alcohol products were isolated after aqueous workup in moderate to excellent yield (48–97%).

( Z )-β-Butyltellanyl α,β-unsaturated carbonyl compounds were stereoselectively produced by hydrotelluration of alkynones or by an addition/elimination sequence from enol tosylates. The β-butyltellanyl-enones were chemoselectively reduced with NaBH 4 /MeOH, NaBH 4 ·CeCl 3 ·7H 2 O/MeOH and DIBAL-H systems to the corresponding allylic alcohols with retention of the Z stereochemistry.

Understanding the processes that determine above-ground biomass (AGB) in Amazonian forests is important for predicting the sensitivity of these ecosystems to environmental change and for designing and evaluating dynamic global vegetation models (DGVMs). AGB is determined by inputs from woody productivity [woody net primary productivity (NPP)] and the rate at which carbon is lost through tree mortality. Here, we test whether two direct metrics of tree mortality (the absolute rate of woody biomass loss and the rate of stem mortality) and/or woody NPP, control variation in AGB among 167 plots in intact forest across Amazonia. We then compare these relationships and the observed variation in AGB and woody NPP with the predictions of four DGVMs. The observations show that stem mortality rates, rather than absolute rates of woody biomass loss, are the most important predictor of AGB, which is consistent with the importance of stand size structure for determining spatial variation in AGB. The relationship between stem mortality rates and AGB varies among different regions of Amazonia, indicating that variation in wood density and height/diameter relationships also influences AGB. In contrast to previous findings, we find that woody NPP is not correlated with stem mortality rates and is weakly positively correlated with AGB. Across the four models, basin-wide average AGB is similar to the mean of the observations. However, the models consistently overestimate woody NPP and poorly represent the spatial patterns of both AGB and woody NPP estimated using plot data. In marked contrast to the observations, DGVMs typically show strong positive relationships between woody NPP and AGB. Resolving these differences will require incorporating forest size structure, mechanistic models of stem mortality and variation in functional composition in DGVMs. © 2016 The Authors. Global Change Biology Published by John Wiley & Sons Ltd.