Extreme Value Statistics of the Total Energy in an Intermediate Complexity Model of the Mid-latitude Atmospheric Jet. Part I: Stationary case

A baroclinic model for the atmospheric jet at middle-latitudes is used as a stochastic generator of time series of the total energy of the system. Statistical inference of extreme values is applied to yearly maxima sequences of the time series, in the rigorous setting provided by extreme value theory. In particular, the Generalized Extreme Value (GEV) family of distributions is used here. Several physically realistic values of the parameter $T_E$, descriptive of the forced equator-to-pole temperature gradient and responsible for setting the average baroclinicity in the atmospheric model, are examined. The location and scale GEV parameters are found to have a piecewise smooth, monotonically increasing dependence on $T_E$. This is in agreement with the similar dependence on $T_E$ observed in the same system when other dynamically and physically relevant observables are considered. The GEV shape parameter also increases with $T_E$ but is always negative, as \textit{a priori} required by the boundedness of the total energy of the system. The sensitivity of the statistical inference process is studied with respect to the selection procedure of the maxima: the roles of both the length of maxima sequences and of the length of data blocks over which the maxima are computed are critically analyzed. Issues related to model sensitivity are also explored by varying the resolution of the system

Hidden benefits and risks of partial protection for coral reef fisheries

Partially protected areas are now the dominant global form of spatial management aimed at preserving ecosystem integrity and managing human use. However, most evaluations of their efficacy use only a narrow set of conservation indicators that reflect a fraction of ways in which protection can succeed or fail. In this paper, we examine three case studies of partially protected coral reef fishery systems to evaluate benefits and risks of their use as a management tool. We use data from community-based management arrangements in three Pacific Island countries to demonstrate three vignettes of how partial protection can boost fisheries production, enhance the ease with which fishers catch their prey, and alter the composition of fisheries yields. These changes in fisheries productivity, catchability, and vulnerability under partial protection carry substantial benefits for fishers. However, they also carry significant risks for ecosystems and fisheries livelihoods unless adaptively managed so as to confer the short to medium term benefits in resource performance without risking longer term sustainability

Digestion of Starch Granules from Maize, Potato and Wheat by Larvae of the the Yellow Mealworm, Tenebrio molitor and the Mexican Bean Weevil, Zabrotes subfasciatus

Scanning electron microscopy images were taken of starch granules from different sources following exposure in vivo and in vitro to gut α-amylases isolated from Tenebrio molitor L. (Coleoptera: Tenebrionidae) and Zabrotes subfasciatus Boheman (Coleoptera: Bruchidae). One α-amylase was isolated from whole larval midguts of T. molitor using non-denaturing SDS-PAGE, while two other α-amylase fractions were isolated from whole larval midguts of Z. subfasciatus using hydrophobic interaction chromatography., Digested starch granules from larvae fed on maize, potato or wheat were isolated from midgut contents. Combinations of starch granules with isolated α-amylases from both species showed similar patterns of granule degradation. In vitro enzymatic degradation of maize starch granules by the three different α-amylase fractions began by creating small holes and crater-like areas on the surface of the granules. Over time, these holes increased in number and area resulting in extensive degradation of the granule structure. Granules from potato did not show formation of pits and craters on their surface, but presented extensive erosion in their interior. For all types of starch, as soon as the interior of the starch granule was reached, the inner layers of amylose and amylopectin were differentially hydrolyzed, resulting in a striated pattern. These data support the hypothesis that the pattern of starch degradation depends more on the granule type than on the α-amylase involved

The role of frequency doubling perimetry in the diagnosis of glaucoma: screening in employees of a public hospital in an urban area of São Paulo

PURPOSE: To study the prevalence of glaucoma in employees of a public hospital in São Paulo and to analyze the role of frequency doubling perimetry along with non-contact tonometry and direct ophthalmoscopy, in the screening for glaucoma. METHODS: 612 employees of the Central Hospital of the Santa Casa de São Paulo were evaluated from October 15 to 20, 2000; 438 were women and 174 men, with mean age of 45.05±7.7 years (range, 35 to 81 years); 437 were white, 104 mulatto, 43 black and 28 Asian. All examinations were done by 10 eye specialists with experience in glaucoma. All employees had both eyes examined, by means of frequency doubling perimetry (FDT), ophthalmoscopy (FO), and non-contact tonometry (TNC). RESULTS: 159 (25.98%) subjects presented with at least one abnormal testing; 5 (3.14%) had high IOP (TNC+); 13 (8.17%) presented suspicious disk (FO+); 110 (69.18%) presented abnormal FDT (FDP+); 8 (5.03%) TNC+ and FO+; 10 (6.28%) had TNC+ and FDT+; 9 (5.66%) presented FO+ and FDT+; 4 (2.51%) had TNC+, FO+ and FDT+; 12 (1.96%) individuals were diagnosed with glaucoma, four of whom (0.65%), with normal pressure glaucoma. CONCLUSIONS: Frequency doubling perimetry was found to be an important step in the screening for glaucoma in the study. Of the 12 individuals that had the diagnosis of glaucoma, 5 (41.6%) would not have been diagnosed if they had not undergone frequency doubling perimetry.OBJETIVO: Estudar a prevalência de glaucoma, em funcionários da Santa Casa de Misericórdia de São Paulo e analisar a validade da inclusão da perimetria de freqüência dupla junto à tonometria de não-contato e à oftalmoscopia direta, na triagem para glaucoma. MÉTODOS: Foram examinados 612 funcionários voluntários, 438 mulheres e 174 homens, com idade média de 45,05±7,7 anos. Eram 437 da raça branca, 104 mulatos, 43 da raça negra e 28 da raça amarela. Todos os funcionários tiveram ambos os olhos examinados por especialistas em glaucoma, que realizaram os seguintes exames: perimetria de freqüência dupla (FDT), oftalmoscopia direta (FO), tonometria de não-contato (TNC). RESULTADOS: Dos 612 indivíduos triados, 159 (25,98%) apresentaram alguma anormalidade em pelo menos um dos exames: 5 (3,14%) apresentaram pressão intra-ocular elevada (TNC+); 13 (8,17%) apresentaram oftalmoscopia suspeita (FO+); 110 (69,18%) apresentaram perimetria de freqüência dupla alterado (FDT+); 8 (5,03%) TNC+ e FO+; 10 (6,28%) TNC+ e FDT+; 9 (5,66%) FO+ e FDT+; 4 (2,51%) TNC+, FO+ e FDT+. Foram detectados 12 (1,96%) indivíduos com glaucoma, quatro dos quais (0,65%) com glaucoma de pressão normal. CONCLUSÕES: A perimetria de freqüência dupla mostrou-se útil para o rastreamento de glaucoma dentro da amostragem estudada. Do total de 12 indivíduos que tiveram o diagnóstico de glaucoma, 5 (41,6%) não teriam sido detectados se não tivessem sido submetidos a perimetria de freqüência dupla.Santa Casa de São Paulo Departamento de OftalmologiaSanta Casa de Misericórdia de São Paulo Departamento de Oftalmologia Setor de GlaucomaUniversidade Federal de São Paulo (UNIFESP) Departamento de OftalmologiaSanta Casa de São Paulo Faculdade de Ciências Médicas Departamento de OftalmologiaUNIFESP, Depto. de OftalmologiaSciEL

Structural, morphological, and magnetic characterizations of (FexMn1-x)2O3 nanocrystals: A comprehensive stoichiometric determination

Iron manganese trioxide (FexMn1-x)2O3 nanocrystals were synthesized by the sol-gel method. The 80 K Mossbauer spectrum was well-fitted using two doublets representing the 8b and 24d crystallographic sites of the (FexMn1-x)2O3 phase and two weak extra sextets which were attributed to crystalline and amorphous hematite. Our findings showed formation of a bixbyite primary phase. The Raman spectrum exhibits six Raman active modes, typical of (Fe,Mn)2O3, and two extra Raman modes associated with the secondary hematite phase. X-ray photoelectron spectroscopy analysis confirmed the presence of oxygen vacancy onto the (FexMn1-x)2O3 particle surface, with varying oxidation states. X-band magnetic resonance data revealed a single broad resonance line in the whole temperature range (3.8 K - 300 K). The temperature dependence of both resonance field and resonance linewidth shows a remarkable change in the range of 40 - 50 K, herein credited to surface spin glass behavior. The model picture used assumes (FexMn1-x)2O3 nanoparticles with a core-shell structure. Results indicate that below about 50 K the spin system of shell reveals a paramagnetic to spin glass-like transition upon cooling, with a critical temperature estimated at 43 K. In the higher temperature range, the superparamagnetic hematite (secondary) phase contributes remarkably to the temperature dependence of the resonance linewidth. Zero-field-cooled (ZFC) and fieldcooled (FC) data show strong irreversibility and a peak in the ZFC curve at 33 K, attributed to a paramagnetic-ferrimagnetic transition of the main phase. Hysteresis curve at 5 K shows a low coercive field of 4 kOe, with the magnetization not reaching saturation at 70 kOe, suggesting the occurrence of a ferrimagnetic core with a magnetic disorder at surface, characteristic of core-shell spin-glass-like behavior

Competitividade e dimensões culturais: uma análise a partir dos blocos econômicos União Europeia e Unasul

The twentieth century has witnessed the formation of various alliances and trade blocs among nations. These alliances have often been more based on geographic and economic proximity than on cultural similarity. However, culture might be an essential factor in the explanation of some discrepancies between countries of the same trade bloc, such as the competitiveness indicators. Therefore, this study aims to analyze the relationship between national culture and the competitiveness index of nations, in the context of UNASUR and the European Union. By means of correlation analysis and clustering (K-means), it was possible to identify a strong correlation between the dimensions of national culture proposed by Hofstede and the nations’ competitiveness indicators. Most countries in South America have great similarities in cultural dimensions and form a single cluster, while countries in the European Union have higher distinctions and are separated into two distinct clusters. Finally, MANOVA tests applied on the clusters reveal that the differences found in relation to the dimensions of national culture are also reflected in the market efficiency indicators of the countries. Thus, the results taken together suggest the need to consider the impact exerted by the culture on the competitiveness of nations.O século XX testemunhou a formação de alianças e blocos econômicos entre as nações, frequentemente embasadas pelas proximidades geográficas e pelos aspectos econômicos do que culturais. Entretanto, a cultura pode ser vista como um aspecto essencial, no sentido de explicar algumas discrepâncias existentes, até mesmo, entre países de um mesmo bloco, como por exemplo, os índices de competitividade. Assim, este estudo busca analisar os aspectos da cultura nacional e da competitividade entre os países, no contexto da Unasul e da União Europeia. Através de análises de correlação e de cluster (K-means), verificou-se forte correlação entre as dimensões de cultura nacional propostas por Hofstede e os respectivos índices de competitividade. A maioria dos países da América do Sul apresenta grandes similaridades nas dimensões culturais, formando um único cluster, enquanto os países da União Europeia apresentam maiores diferenças e se separam em dois clusters distintos. Por fim, testes MANOVA aplicados sobre os clusters encontrados revelam que as diferenças em relação às dimensões de cultura nacional se refletem também nos índices de eficiência de mercado dos países. Desta forma, os resultados em conjunto apontam a necessidade de se considerar o impacto exercido pela cultura sobre a competitividade

World Health Organization Guidelines for Management of Acute Stress, PTSD, and Bereavement: Key Challenges on the Road Ahead

Wietse Tol and colleagues discuss some of the key challenges for implementation of new WHO guidelines for stress-related mental health disorders in low- and middle-income countries. Please see later in the article for the Editors' Summar

Hidden benefits and risks of partial protection for coral reef fisheries

Partially protected areas are now the dominant global form of spatial management aimed at preserving ecosystem integrity and managing human use. However, most evaluations of their efficacy use only a narrow set of conservation indicators that reflect a fraction of ways in which protection can succeed or fail. In this paper, we examine three case studies of partially protected coral reef fishery systems to evaluate benefits and risks of their use as a management tool. We use data from community-based management arrangements in three Pacific Island countries to demonstrate three vignettes of how partial protection can boost fisheries production, enhance the ease with which fishers catch their prey, and alter the composition of fisheries yields. These changes in fisheries productivity, catchability, and vulnerability under partial protection carry substantial benefits for fishers. However, they also carry significant risks for ecosystems and fisheries livelihoods unless adaptively managed so as to confer the short to medium term benefits in resource performance without risking longer term sustainability