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We present a theoretical study proposes an approach for easy understanding of the magnetic properties of rare-earth (TR) dysprosium (Dy) and holmium (Ho) from the electronic structure of these elements. The unpaired electrons in the 4f orbitals give rise magnetism of the TR, so that they present high values of magnetic moment compared to other chemicals. Nanomagnetic systems involving artificial nanolayers of Dy and Ho have been studied extensively in recent years, due mainly to the exotic magnetic phases presented by these materials, favoring, increasingly, the emergence of new magnetic properties in these systems, industries and interest of the magneto-electronic and magnetic refrigeration. [ABSTRACT FROM AUTHOR]

The X-ray diffraction data of l-serine anhydrous crystalswas taken into account to initialize the total energy minimizationprocess of their unit cell through density functional theory (DFT)computations, which were performed within both the local density andgeneralized gradient approximations with dispersion, LDA, and GGA+D,respectively. The calculated lattice parameters are in good agreementwith the experimental results for the dispersion corrected generalizedgradient approximation functional, with a unit cell volume largerby only about 0.32%; the Mulliken and Hirschfield charges show thezwitterionic state of the l-serine molecules in the DFT convergedcrystals. The electronic (band structure, density of states) and opticalabsorption properties were calculated to explain the light absorptionof the l-serine anhydrous crystalline powder we have measuredat room temperature. The optical absorption related to transitionsbetween the top of the valence band and the bottom of the conductionband involves O-2p valence states and H-1s conduction states. TheLDA (4.74 eV) and GGA+D (4.75 eV) estimated energy gaps are about1 eV below the estimated value from optical absorption measurements(5.90 eV). Small values were obtained for the electron effective masses,which are almost isotropic, whereas large anisotropic values werefound for hole effective masses, suggesting that the l-serineanhydrous crystal behaves like an n-type wide gap semiconductor. Differentdielectric function profiles obtained for some of the most importantsymmetry directions also demonstrate the optical anisotropy of l-serine anhydrous crystals. [ABSTRACT FROM AUTHOR]

The National Centers for Environmental Prediction (NCEP) ETA regional circulation model (RCM) was one-way nested in the T62 NCEP general circulation model for a series of 3-month simulations of the austral summer and winter over South America (SA). The intensity-scale verification technique (ISVT), based on the scale decomposition of precipitation skill score and energy relative difference, was used to quantitatively assess the dynamic-downscaling ability of seasonal precipitation and inter-annual precipitation difference. The ISVT showed that the RCM was able to add value to summer and winter rainfall forecasts over southern South America. Largest improvements were associated to precipitation events at spatial scales of about 400-800 km and rainfall rates above 4 mm day. In general, downscaling failed to yield better results over northern South America. In terms of inter-annual precipitation difference, the RCM produced better results over southern South America, by simulating the increase in intense small-scale events in the wet years. Analysis of meridional moisture flux associated with the South American low-level jet (SALLJ) suggested that the Andean topography plays an important role in the RCM's rainfall simulations over the La Plata basin. A sensitivity test with lowered Andean topography heights produced weaker moisture advection by the SALLJ, and lower rainfall totals over that basin for both seasons. During summer, results showed that the reduced rainfall was associated with deteriorated simulations of mid- to large-scale precipitation events, whereas during winter it was associated with deteriorated simulations of smaller-scale events. Copyright © 2010 Royal Meteorological Society [ABSTRACT FROM AUTHOR]

The chemical composition of the essential oils obtained by hydrodistillation from the aerial parts of two populations of Vitex rivularis (subgenus Vitex) collected during the flowering phase of the plants was investigated by gas chromatography and gas chromatography/mass spectroscopy. Sesquiterpene hydrocarbons were the main group in both samples, the main compound being germacrene D. This composition is markedly different from that of the other African species, with the exception of Vitex ferruginea subsp. amboniensis, which belongs to the same subgenus as V. rivularis. Minimal inhibitory concentrations (MIC) and minimal lethal concentrations (MLC) were used to evaluate the anti-fungal activity against yeasts and dermatophyte strains. The oils exhibited significant anti-fungal activity against dermatophyte strains with MIC and MLC values ranging from 0.16 to 0.64 µL mL-1 and 0.32 to 2.5 µL mL-1, respectively. For some strains, MIC values were similar to MLC values, indicating the fungicidal activity of the oils. Nevertheless, these oils showed low activity against Candida spp. strains. [ABSTRACT FROM AUTHOR]

A simple, rapid, and precise amperometric method for quantification of N-methylcarbamate pesticides in water samples and phytopharmaceuticals is presented. Carbofuran and fenobucarb are the target analytes. The method is developed in flow conditions providing the anodic oxidation of phenolic-based compounds formed after alkaline hydrolysis. Optimization of instrumental and chemical variables is presented. Under the optimal conditions, the amperometric signal is linear for carbofuran and fenobucarb concentrations over the range of 1.0 × 10-7 to 1.0 × 10-5 mol L-1, with a detection limit of about 2 ng mL-1. The amperometric method is successfully applied to the analysis of spiked environmental waters and commercial formulations. The proposed method allows 90 samples to be analysed per hour, using 500 µL of sample, and producing wastewaters of low toxicity. The proposed method permits determinations at the µg L-1 level and offers advantages of simplicity, accuracy, precision, and applicability to coloured and turbid samples, and automation feasibility. [ABSTRACT FROM AUTHOR]

The aim of the present study was to evaluate the pharmacokinetic profile of lamotrigine (LTG) in epileptic patients submitted to video-electroencephalography (VEEG) monitoring and, in addition, to investigate the influence of concomitant antiepileptic drugs (AEDs) on the kinetics of LTG. The analysis assumed a one-compartment open model with first-order absorption and elimination. The kinetic estimates obtained in this population were validated by using the Prediction-Error approach. The influence of medication was also assessed by the calculation of the LTG concentration-to-dose ratio. Patients ( n=135) were divided into four groups according to the co-medication: Group 1, patients taking LTG with enzyme-inducer agents; Group 2, patients receiving LTG with valproic acid; Group 3, patients receiving both inducers and inhibitors of LTG metabolism; Group 4, patients under AEDs not known to alter LTG metabolism. The obtained estimates for clearance (CL) (L/h/kg) [0.075±0.029 (Group 1), 0.014±0.005 (Group 2), 0.025±0.008 (Group 3) and 0.044±0.011 (Group 4)] appear to be the most appropriate set to be implemented in clinical practice as prior information, as demonstrated by the accuracy and precision of the measurements. In addition, the influence of co-medication on the LTG profile was further confirmed by the basal LTG concentration-to-dose ratio. The results of the present investigation may contribute to achieving the goal of optimizing patients’ clinical outcomes by managing their medication regimen through measured drug concentrations. Patients submitted to VEEG monitoring may benefit from this study, as the results may be used to provide better drug management in this medical setting. [ABSTRACT FROM AUTHOR]

This study explores the role of vegetation biophysical processes (VBPs) in the structure and evolution of the South American monsoon system (SAMS) with an emphasis on the precipitation field. The approach is based on comparing ensemble simulations by the National Centers for Environmental Prediction general circulation model (GCM) in which the land surface parameterization in one ensemble includes an explicit representation of vegetation processes in the calculation of surface fluxes while the other does not [GCM/Simplified Simple Biosphere Model (SSiB) and GCM/Soil, respectively], but with similar monthly mean surface albedo and initial soil moisture. The ensembles consist of five pairs of 1-yr integrations differing in the initial conditions for the atmosphere. The results show that, during the austral summer, consideration of explicit vegetation processes does not alter the monthly mean precipitation at the planetary scale. However, at continental scales, GCM/SSiB produces a more successful simulation of SAMS than GCM/Soil. The improvement is particularly clear in reference to the seasonal southward displacement of precipitation during the onset of the SAMS and its northward merging with the intertropical convergence zone during the monsoon mature stage, as well as better monthly mean austral summer precipitation over the South American continent. The changes in surface water and energy balances and circulation in October (monsoon onset) and December (the start of the monsoon mature stage) were analyzed for a better understanding of the results and mechanisms involved. It was found that the major difference between the simulations is in the partitioning of latent heat and sensible heat fluxes (i.e., different Bowen ratio), which produced different latitudinal and longitudinal thermal gradients at the surface. A stronger sensible heat flux gradient between continent and ocean in the GCM/SSiB simulation helped generate an enhanced ventilation effect, which lowered moist static energy (MSE) over the northeast coast of South America leading to stronger counterclockwise turning of the low-level wind from the Atlantic Ocean toward the continent during the premonsoon and early monsoon stages, modifying moisture flux convergence (MFC). It was further identified that the seasonality of savanna and shrublands to the south and east of the Amazon rain forest contributed to the variability of heating gradients and influenced the SAMS onset and its northward merge with the ITCZ at the early monsoon mature stage. The comparison of the differences between precipitation, evaporation, advection of MSE, and MFC based on simulations using two different land parameterizations suggested that the VBP modulated the surface water budget, but its impact on precipitation was determined by the changes in circulation via changes in heat gradient and MSE. [ABSTRACT FROM AUTHOR]

Background. Galectin-3 (Gal-3) is a member of the family of β-galactoside-binding mammalian lectins, and has been implicated in tumour invasion and metastatic process in vitro and in vivo. Aim. To determine whether an increase in serum Gal-3 production could be found in patients with advanced metastatic melanoma. Methods. We collected 18 sera from patients with AJCC stage IV metastatic melanomas and 20 sera from healthy volunteers. Determination of Gal-3 was performed by ELISA, and in the group of patients with melanoma, these results were compared with the serum lactate dehydrogenase (LDH) and the C-reactive protein (CRP) concentrations. Results. Gal-3 concentration was shown to be significantly higher in the group of patients with melanoma compared with healthy volunteers, and Gal-3 concentration was significantly correlated with both LDH and CRP in the melanoma group. We also selected four patients in the melanoma group for Gal-3 retrospective immunostaining analysis on cutaneous metastases. Two of these patients, who had a higher Gal-3 serum level, showed more intense staining and the other two patients, with a lower serum level of Gal-3, had moderate immunostaining, suggesting that at least part of serum Gal-3 might be produced by metastatic melanoma tissue. Conclusions. Gal-3 might play a role in melanoma progression and/or inflammation, and warrants further study. [ABSTRACT FROM AUTHOR]

Aim. – Metastases of melanoma are frequent. On the gastro-intestinal tract, commonest localizations are small bowel, stomach and colon. Surgical treatment of digestive metastases from melanoma is not well known and its value is still debated.Patients and methods. – Medical records of 10 patients (six female and four male) operated for metastatic melanoma to gastro-intestinal tract were reviewed to determine results of surgery.Results. – Gastro-intestinal metastases were symptomatic in eight patients (abdominal pain in three, bowel obstruction in three, abdominal mass and obstructive jaundice in one each). Two patients had anemia. Diagnosis has been suggested by imaging in seven patients and endoscopy in three. All patients were operated on by laparotomy for resection of metastases located on small bowel in four patients, gallbladder in two, stomach in two and colon in two. Complete resection suppressed symptoms in nine cases. In one patient, resection was incomplete but provided satisfying symptomatic relief. One patient died at day 3; in other patients, median survival was 18 months (range: 3–120).Conclusion. – In a patient with previous history of melanoma, digestive symptoms indicate morphological explorations due to suspicion of metastases to gastro-intestinal tract. Surgical treatment of these metastases is usually palliative but, in some cases, allows long-term survival. [Copyright &y& Elsevier]

Objective: The aim of our work was to define the kinetic profile of carbamazepine (CBZ), in order to improve on dosing schedules through a Bayesian approach. Method: Carbamazepine dose/steady-state trough concentrations data pairs and associated information were collected retrospectively on a population of adult epileptic patients. Results: Fifty patients (index population) with two or more available concentrations (total of 174 determinations) met our inclusion criteria. Patients were taking CBZ (200–1800 mg/day) in mono- or polytherapy regimens. The analysis assumed a one-compartimental model with first-order absorption and elimination. Due to the data source (only trough concentrations were measured as part of hospital routine), the volume of distribution was fixed at 1·19 l/kg. The final estimates for CL were: 0·075± 0·027 (mono- and polytherapy), 0·069±0·020 (monotherapy), and 0·106±0·037 l/h/kg (polyItherapy). In order to validate these results, we assessed their predictive capacity using 18 new patients (validation population), submitted to the same inclusion criteria and using Prediction-Error analysis. The results suggested a different CL value for our population compared to earlier published clearance values. The results also pointed to an increased metabolic rate associated with polytherapy. The prediction capacity of the optimization method derived from a Portuguese population made in an a priori evaluation indicated a low error (–0·04 μg/ml), close to the theoretical zero value. Conclusion: Our results provide specific data on CBZ disposition in a Portuguese population and given the wide variability in the literature values, our data may help improve dosing of CBZ in Portuguese patients. [ABSTRACT FROM AUTHOR]

An account of the Apiaceae (Umbelliferae) for the Flore de Madagascar et des Comores (Paris) has recently been completed and submitted for publication (Sales and Hedge 2004). The flora account deals with 15 genera and 31 species in the subfamilies Hydrocotyloideae, Saniculoideae and Apioideae; some of the species are globally widespread and/or doubtfully native. Five new species will be described in Peucedanum (2), Phellolophium (1) and Pimpinella (2). Here, we concentrate on subfam. Apioideae, draw attention to some features of special interest and provide a checklist of the native 11 genera and 20 species currently known to occur in Madagascar. [ABSTRACT FROM AUTHOR]

Merkel cell carcinoma is an aggressive neuroendocrine skin tumor whose treatment modality is still controversial. It resembles malignant melanoma in its cutaneous presentation, unpredictable biologic behavior, early regional lymph node involvement, early distant metastases, and high recurrence rate. Regarding these common features, we used sentinel node biopsy (a well-described technique for the treatment of malignant melanoma) in a 50-year-old man with Merkel cell carcinoma of the left arm. Only one sentinel lymph node was identified and it was revealed to be disease-free on histology. No further axillary dissection was performed. This case report shows that sentinel node biopsy is applicable to Merkel cell carcinoma. [ABSTRACT FROM AUTHOR]

Unlabelled: Although rare, malignant melanoma does occur in children. As in adults, prognosis clearly depends on rapid diagnosis and early treatment. This paper describes eight cases of confirmed malignant melanoma in children, with full case history and pathological findings. Mean follow-up was 109.8 months. Early diagnosis and low Breslow indices provide good results in the form of absence of recurrence and long-term survival prognosis. The paper also includes a discussion of specific risk factors affecting children. In order to encourage earlier diagnosis and improved prognosis, it must be kept in mind that in children too, the skin as an organ should be included in any physical examination.Conclusion: As for adult patients, early clinical detection, speedy histological confirmation and prompt surgery is the only way to achieve a long survival period for children suffering from malignant melanoma. [ABSTRACT FROM AUTHOR]

The major cause of lamb mortality in grazing systems at birth is starvation and/or exposure to cold complex, with hypothermia being a primary contributing factor. In precocial species such as sheep, the ability to produce the heat required to prevent hypothermia during the first 12 h after birth relies heavily on the nonshivering thermogenesis, via brown adipose tissue (BAT). Therefore, insufficient BAT deposits, or inability to metabolize BAT, are the major factors contributing to lamb death resulting from starvation/exposure. Circulating concentration of melatonin is associated with proper amount and functionality of BAT. However, there is limited information on the effect of increased melatonin levels, via maternal supplementation, on fetal BAT deposition. The objective was to establish the effect of melatonin implants (M) in single- and twin-bearing ewes, on fetal BAT deposits. Corriedale ewes were synchronized, superovulated, mated to Suffolk rams, and managed under commercial grazing conditions. Single (S)- and twin (T)-bearing ewes received 0 (M0), 1 (M1), or 2 (M2) commercial 18-mg melatonin implants (Regulin) at 100 d of gestation (n = 8 per group). Ewes were euthanized at d 140 of gestation, and total fetal perirenal fat (BAT) was excised and weighed. The effect of litter size (S vs. T), number of implants (M0, M1, or M2), and their interaction on fetal biometrics were analyzed using ANOVA. A rank × treatment interaction (P = 0.002) was observed for total BAT, where SM2 fetuses tended to have 18% more BAT compared with SM0 (P = 0.1) and SM1 fetuses (P = 0.09; 22.8 ± 1.6 vs. 19.3 ± 1.5 or 19.2 ± 1.5 g), whereas TM1 fetuses had approximately 35% more BAT compared with TM0 (P = 0.0002) and TM2 fetuses (P = 0.0003; 22.9 ± 1.1 vs. 17.1 ± 1.0 or 16.9 ± 1.1 g). Single and twin M2 fetuses tended to be 5 to 8% heavier compared with single and twin M0 and M1 fetuses (4.1 ± 0.1, 3.8 ± 0.1, and 3.9 ± 0.1 kg, respectively; P = 0.09). In addition, M2 fetuses, compared with M0 and M1 fetuses, showed greater fetal thorax diameter (34.6 ± 0.4, 33.8 ± 0.3, and 33.9 ± 0.3 cm, respectively; P = 0.047) and presented a trend for increased crown-rump length (44.1 ± 0.5, 43.0 ± 0.4, and 42.6 ± 0.5 cm, respectively; P = 0.056). These results indicate that maternal melatonin implants from d 100 of gestation increases BAT deposition, especially in twin fetuses, and may increase BW. Both effects may have important implications for newborn lamb survival under commercial grazing conditions. Funded by CONICYT project number 11150998. [ABSTRACT FROM AUTHOR]