Human impacts outpace natural processes in the Amazon.

Amazonian environments are being degraded by modern industrial and agricultural activities at a pace far above anything previously known, imperiling its vast biodiversity reserves and globally important ecosystem services. The most substantial threats come from regional deforestation, because of export market demands, and global climate change. The Amazon is currently perched to transition rapidly from a largely forested to a nonforested landscape. These changes are happening much too rapidly for Amazonian species, peoples, and ecosystems to respond adaptively. Policies to prevent the worst outcomes are known and must be enacted immediately. We now need political will and leadership to act on this information. To fail the Amazon is to fail the biosphere, and we fail to act at our peril.

Finite element simulations of a hip joint with femoroacetabular impingement.

In this study, a three-dimensional finite element (FE) model based on the specific anatomy of a patient presenting a femoroacetabular impingement of the 'cam'-type is developed. The FE meshes of the structures of interest are obtained from arthrographic magnetic resonance images. All soft tissues are considered linear elastic and isotropic, and the bones were assumed rigid. A compression of the femur on the acetabular cavity as well as flexural movements and internal rotations are applied. Stresses and contact pressures are evaluated in this patient-specific model in order to better interpret the mechanism of aggression of the femoral and acetabular cartilages. The corresponding results are presented and discussed. The values obtained for the contact pressures are similar to those reported by other models based on idealised geometries. An FE analysis of a non-cam hip is also performed for comparison with the pathological case.

Determination of heats of tautomerization nitrile-ketenimine by mass spectrometry.

Tautomerism of some nitriles has been studied by mass spectrometry. The analysis of the corresponding mass spectra has allowed to assign some fragmentations to specific tautomers and to determine heats of tautomerization through temperature effects and electron energy studies. Experimental determinations are supported by theoretical calculations. The joint analysis of mass spectrometry and DFT-B3LYP data indicate that this tautomeric equilibrium can be studied by the experimental spectrometric strategy employed.

The evidence for the occurrence of tautomeric structures for selected aldehydes and thioaldehydes.

Mass spectra of selected aldehydes and thioaldehydes have been analyzed and specific fragmentation assignments have been done to keto and enol tautomers, although many peaks can be assigned to both forms (i.e. mass spectra are superimposed on one another). The enolization rate for aldehydes is generally favored by the increase in the steric effect caused by α substitution to the carbonyl group. The analysis of the corresponding mass spectra has allowed to establishing an acceptable correlation between selected ion abundances ratios and approximate enolization equilibrium constants (carried out by means of DFT calculations). The influence of temperature on the enol/keto selected fragments abundance ratios (for different aldehydes and thioaldehydes and for different pair of ions of the same compound whenever possible) is studied in order to estimate the enthalpy difference for the tautomeric equilibria. The results indicate that the thioketo-thioenol equilibrium can be studied by mass spectrometry and the ionization in the ion source have negligible effect on the position of that equilibrium.

Mass spectral study of the occurrence of tautomeric forms of thiohydantoins.

Mass spectrometry is used to evaluate the occurrence of thio-enol structures among the several possible tautomers of thiohydantoins and dithiohydantoins. Mass spectra of differently substituted thiohydantoins are examined looking for common mass spectral behaviors. Ion fragmentations from specific tautomers allow to predict the most stable thio-enol structure for both type of compounds. The mass spectrum of the alkylation product of 5,5- dimethyldithiohydantoin and the nuclear magnetic resonance spectra of the alkylation products of both 2- thiohydantoin and dithiohydantoin support the fact that the most likely thio-enolstructure is determined by the presence of one or two thio-carbonyl groups in the hydantoin molecule.

Mass spectrometry of beta-ketoesters. Some evidence of their tautomerism.

Mass spectrometric evidence of tautomerism is reported for beta-ketoesters. The analysis of the corresponding mass spectra has allowed specific assignment of fragment ions to tautomers. The predictive value of this methodology is supported by the influence of substitution pattern of these compounds on these equilibria. Experimental data are strongly supported by Austin Model 1 semiempirical calculations indicating that mass spectrometry could be resourced as a tool for the investigation of tautomerism of neutral species in the gas phase.

Chronic infantile neurological cutaneous and articular/neonatal onset multisystem inflammatory disease syndrome: ocular manifestations in a recently recognized chronic inflammatory disease of childhood.

OBJECTIVE: To report on the ocular manifestations of the Chronic Infantile Neurological Cutaneous and Articular/Neonatal Onset Multisystem Inflammatory Disease (CINCA/NOMID) syndrome, a rare, recently identified, pediatric multisystem inflammatory disease with chronic cutaneous, neurological, and articular manifestations. DESIGN: Descriptive case-report study. SETTING: International collaborative study based on a questionnaire. RESULTS: We included 31 patients. The mean age at onset of eye manifestations was 4.5 years. Optic disc changes were the most common feature, occurring in 26 patients (83%), including optic disc edema, pseudopapilledema, and optic atrophy. Anterior segment manifestations varying from mild to severe were seen in 13 patients (42%); chronic anterior uveitis, in 17 patients (55%). Moderate to severe visual acuity loss in at least 1 eye was seen in 8 patients (26%) as a consequence of the disease. Posterior synechia, glaucoma, and white iritis were not observed in any patient. CONCLUSION: Ocular manifestations with potentially sight-threatening complications occur commonly in the CINCA/NOMID syndrome. The distinctive nature of these complications may assist the ophthalmologist in recognizing this rare disorder and distinguishing it from juvenile rheumatoid arthritis.