Efectos de la reducción del nivel del Lago Chad sobre la Seguridad Regional (Nigeria, Níger, Chad y Camerún) durante el período de 2000-2010

El Lago Chad ha sido durante varias décadas, una fuente de supervivencia económica para millones de personas que habitan en cuatro Estados a saber; Nigeria, Níger, Chad y Camerún. No obstante, el cambio climático, el aumento acelerado de la población, la explotación insostenible y la mala regulación de los Estados ribereños han sido los principales factores que han dado lugar, en la última década, a la dramática reducción del nivel del Lago Chad. Teniendo en cuenta que los Estados aledaños al Lago, se encuentran inmersos en una Interdependencia Compleja, este nuevo contexto, ha tenido un impacto directo en la región, debido a que ha agravado otras variables económicas, sociales, ambientales y políticas, dejando un ambiente de inseguridad regional. De esta manera, la reducción de la Cuenca del Lago Chad representa una amenaza compartida que vincula estrechamente a Nigeria, Níger, Chad y Camerún, lo que permite vislumbrar la existencia de un Subcomplejo de Seguridad Regional.

La participación de las ONG en Naciones Unidas y su contribución a la gobernanza global

El objetivo de este trabajo es analizar el fenómeno de la participación de las ONG en el marco de la Organización de Naciones Unidas (ONU) y las implicaciones del mismo en las dinámicas de la gobernanza global. Se explican los conceptos principales para el análisis y posteriormente se hace una revisión de los antecedentes que permitieron el desarrollo de dicho fenómeno dentro de la organización y fuera de ella. Luego se centra el análisis en la incidencia de las ONG en la ONU y para la gobernanza global; se concluye con una reflexión sobre lo que puede esperarse de esta incidencia para el futuro de la organización.

La dimensión transnacional del movimiento feminista marroquí: génesis, desarrollo e impacto social (1980-2008)

Esta monografía busca explicar cómo han incidido el contexto internacional y las relaciones transnacionales en el movimiento feminista de Marruecos. De este modo, este estudio defiende que las Conferencias Mundiales sobre la Mujer de la ONU crearon una estructura de oportunidad política que favoreció el surgimiento y el desarrollo de este movimiento. Asimismo, dicho contexto construyó un espacio para que las activistas feministas marroquíes crearan y se insertaran en Redes de Defensa Transnacional, las cuales contribuyeron a cambiar la condición de la mujer en Marruecos, a través de reformas a los Códigos de Familia y Nacionalidad y el levantamiento de las reservas a la CEDAW. Para esto se hará un estudio interdisciplinario haciendo uso de la teoría de los movimientos sociales y del activismo transnacional. Igualmente, se utilizará una metodología cualitativa, principalmente a través de las herramientas del análisis de contenido y el trabajo de campo de la autora.

El naixement del cinema : 1895-1905. 'El nacimiento del cine : 1895-1905'

Publicado aunque no se ha encontrado el dep??sito legal

Bending, twisting, and breaking CuCN chains to produce framework materials: the reactions of CuCN with alkali-metal halides

The reactions of the low-temperature polymorph of copper(I) cyanide (LT-CuCN) with concentrated aqueous alkali-metal halide solutions have been investigated. At room temperature, KX (X = Br and I) and CsX (X = Cl, Br, and I) produce the addition products K[Cu-2(CN)(2)Br](H2O)-H-. (I), K-3[Cu-6(CN)(6)I-3](.)2H(2)O (II), Cs[Cu-3(CN)(3)Cl] (III), Cs[Cu-3(CN)(3)Br] (IV), and Cs-2[Cu-4(CN)(4)I-2](H2O)-H-. (V), with 3-D frameworks in which the -(CuCN)- chains present in CuCN persist. No reaction occurs, however, with NaX (X = Cl, Br, I) or KCl. The addition compounds, I-V, reconvert to CuCN when washed. Both low- and high-temperature polymorphs of CuCN (LT- and HT-CuCN) are produced, except in the case of Cs[Cu-3(CN)(3)Cl] (III), which converts only to LT-CuCN. Heating similar AX-CuCN reaction mixtures under hydrothermal conditions at 453 K for 1 day produces single crystals of I-V suitable for structure determination. Under these more forcing conditions, reactions also occur with NaX (X = Cl, Br, I) and KCl. NaBr and KCl cause some conversion of LT-CuCN into HT-CuCN, while NaCl and NaI, respectively, react to form the mixed-valence Cu(I)/Cu(II) compounds [Cu-II(OH2)(4)][Cu-4(I)(CN)(6)], a known phase, and [Cu-II(OH2)(4)][Cu-4(I)(CN)(4)I-2] (VI), a 3-D framework, which contains infinite -(CuCN)- chains. After 3 days of heating under hydrothermal conditions, the reaction between KI and CuCN produces [Cu-II(OH2)(4)][Cu-2(I)(CN)I-2](2) (VII), in which the CuCN chains are broken into single Cu-CN-Cu units, which in turn are linked into chains via iodine atoms and then into layers via long Cu-C and Cu-Cu interactions.

A bridge-ship collision avoidance system based on FLIR image sequences

In this paper, a forward-looking infrared (FLIR) video surveillance system is presented for collision avoidance of moving ships to bridge piers. An image preprocessing algorithm is proposed to reduce clutter background by multi-scale fractal analysis, in which the blanket method is used for fractal feature computation. Then, the moving ship detection algorithm is developed from image differentials of the fractal feature in the region of surveillance between regularly interval frames. When the moving ships are detected in region of surveillance, the device for safety alert is triggered. Experimental results have shown that the approach is feasible and effective. It has achieved real-time and reliable alert to avoid collisions of moving ships to bridge piers.

Hcp2, a secreted protein of the phytopathogen Pseudomonas syringae pv. tomato DC3000, is required for competitive fitness against bacteria and yeasts

When analysing the secretome of the plant pathogen Pseudomonas syringae pv. tomato (Pst) DC3000, we identified hemolysin co-regulated protein (Hcp) as one of the secreted proteins. Hcp is assumed to be an extracellular component of the type VI secretion system (T6SS). Two copies of hcp genes are present in the Pst DC3000 genome, hcp1 (PSPTO_2539) and hcp2 (PSPTO_5435). We studied the expression patterns of hcp genes and tested the fitness of hcp knock-out mutants in host plant colonization and in inter-microbial competition. We found that the hcp2 gene is expressed, most actively at the stationary growth phase, and that the Hcp2 protein is secreted via T6SS and appears in the culture medium as covalently linked dimers. Expression of hcp2 is not induced in planta and it does not contribute to virulence or colonisation in tomato or Arabidopsis plants. Instead, hcp2 is required for survival in competition with enterobacteria and yeasts, and its function is associated with suppression of the growth of these competitors. This is the first report on bacterial T6SS-associated genes functioning in competition against yeast. Our results suggest that the T6SS of P. syringae may play an important role in bacterial fitness, allowing this plant pathogen to survive in conditions where it has to compete with other micro-organisms for resources.

Posttranscriptional regulation of sodium-iodide symporter mRNA expression in the rat thyroid gland by acute iodide administration

Serrano-Nascimento C, Calil-Silveira J, Nunes MT. Posttranscriptional regulation of sodium-iodide symporter mRNA expression in the rat thyroid gland by acute iodide administration. Am J Physiol Cell Physiol 298: C893-C899, 2010. First published January 27, 2010; doi:10.1152/ajpcell.00224.2009.-Iodide is an important regulator of thyroid activity. Its excess elicits the Wolff-Chaikoff effect, characterized by an acute suppression of thyroid hormone synthesis, which has been ascribed to serum TSH reduction or TGF-beta increase and production of iodolipids in the thyroid. These alterations take hours/days to occur, contrasting with the promptness of Wolff-Chaikoff effect. We investigated whether acute iodide administration could trigger events that precede those changes, such as reduction of sodium-iodide symporter (NIS) mRNA abundance and adenylation, and if perchlorate treatment could counteract them. Rats subjected or not to methylmercaptoimidazole treatment (0.03%) received NaI (2,000 mu g/0.5 ml saline) or saline intraperitoneally and were killed 30 min up to 24 h later. Another set of animals was treated with iodide and perchlorate, in equimolar doses. NIS mRNA content was evaluated by Northern blotting and real-time PCR, and NIS mRNA poly(A) tail length by rapid amplification of cDNA ends-poly(A) test (RACE-PAT). We observed that NIS mRNA abundance and poly(A) tail length were significantly reduced in all periods of iodide treatment. Perchlorate reversed these effects, indicating that iodide was the agent that triggered the modifications observed. Since the poly(A) tail length of mRNAs is directly associated with their stability and translation efficiency, we can assume that the rapid decay of NIS mRNA abundance observed was due to a reduction of its stability, a condition in which its translation could be impaired. Our data show for the first time that iodide regulates NIS mRNA expression at posttranscriptional level, providing a new mechanism by which iodide exerts its autoregulatory effect on thyroid.

Differential gene expression analysis of iodide-treated rat thyroid follicular cell line PCCl3

The inhibitory effect of supraphysiological iodide concentrations on thyroid hormone synthesis (Wolff - Chaikoff effect) and on thyrocyte proliferation is largely known as iodine autoregulation. However, the molecular mechanisms by which iodide modulates thyroid function remain unclear. In this paper, we analyze the transcriptome profile of the rat follicular cell lineage PCCl3 under untreated and treated conditions with 10 (- 3) M sodium iodide (NaI). Serial analysis of gene expression (SAGE) revealed 84 transcripts differentially expressed in response to iodide (p <= 0.001). We also showed that iodide excess inhibits the expression of essential genes for thyroid differentiation: Tshr, Nis, Tg, and Tpo. Relative expression of 14 of 20 transcripts selected by SAGE was confirmed by real-time PCR. Considering the key role of iodide organification in thyroid physiology, we also observed that both the oxidized form of iodide and iodide per se are responsible for gene expression modulation in response to iodide excess. (c) 2008 Elsevier Inc. All rights reserved.

Fracionamento físico da matéria orgânica do solo em diferentes energias de sonicação em três latossolos brasileiros sob vegetação nativa

O fracionamento físico é freqüentemente empregado, em estudos sobre a dinâmica da matéria orgânica do solo (MOS), sendo que não existe um consenso quanto à energia adequada para a dispersão máxima de um determinado tipo do solo. Os principais objetivos deste trabalho foram determinar a energia de sonicação para a dispersão máxima do solo no fracionamento físico da MOS; avaliar o efeito do aumento da energia de sonicação e da separação prévia da matéria orgânica leve livre (MOLL) na dispersão do solo; e investigar a distribuição e qualidade das substâncias húmicas (SH´s) nas frações silte e argila obtidas na dispersão máxima do solo. O fracionamento físico em seis níveis de energia (200, 400, 800, 1200, 1600 e 2000 J mL-1) foi realizado em amostras do horizonte A de três Latossolos brasileiros sob vegetação nativa: Latossolo Vermelho (LVdf), Latossolo Bruno (LBd) e Latossolo Amarelo (LAw). A não separação da MOLL com solução de NaI, previamente à aplicação de ultra-som, causou redistribuição de carbono nas frações silte e argila, mostrando ser este um procedimento importante no fracionamento da MOS. Em geral, o aumento da energia de sonicação provocou aumento do teor da fração argila, porém a redistribuição do carbono não foi observada. A energia de máxima dispersão foi de 800, 1200 e acima de 2000 J mL-1, respectivamente para os solos LVdf, LAw e LBd, e este comportamento foi relacionado com as características de cada solo A proporção de SH´s em relação ao teor de carbono total da fração, nas frações argila e silte dos solos LVdf e LAw foi superior à verificada para o solo inteiro, enquanto que no solo LBd o comportamento foi inverso. A razão E4/E6 nos ácidos húmicos (AH) na fração argila dos solos LVdf e LBd foi inferior à dos ácidos fúlvicos (AF) correspondentes, indicando que os AH apresentam grau de condensação mais elevado do que AF. Os valores obtidos para a razão E4/E6 foram inferiores aos usualmente citados na literatura. Os resultados obtidos no fracionamento químico indicam que o fracionamento físico afetou a distribuição e qualidade das substâncias húmicas fracionadas quimicamente.

Imuno-histoquímica para o diagnóstico precoce de vitiligo

O vitiligo é uma doença de pele freqüente que acomete 1% da população e é caracterizada por máculas despigmentadas conseqüentes à perda progressiva e localizada dos melanócitos da epiderme. Na maioria dos pacientes, o diagnóstico é feito por exame clínico. A biópsia da pele é realizada quando há necessidade de diagnóstico diferencial com doenças hipocromiantes. O diagnóstico histopatológico de vitiligo é difícil nos preparados corados por hematoxilina e eosina (HE). Há poucos estudos sobre a melhoria da qualidade diagnóstica no vitiligo. OBJETIVO: Avaliar a utilidade dos marcadores imuno-histoquímicos proteína S-100, human melanoma black-45 (HMB-45) e Melan-A para o diagnóstico precoce em casos clinicamente suspeitos ou duvidosos de vitiligo. Material e métodos: Lâminas histológicas de biópsias de pele sã e lesada de 10 pacientes com suspeita clínica de vitiligo coradas pelos métodos de HE, proteína S-100, HMB-45 e Melan-A. Utilizou-se contracoloração com Giemsa como modificação técnica para diferenciar a melanina da imunomarcação. RESULTADOS: Seis casos, com manifestação clínica recente, apresentaram infiltrado linfocitário, do tipo dermatite de interface, na pele lesada na HE. As colorações por S-100, HMB-45 e Melan-A marcaram os melanócitos da camada basal da pele sã, e a proteína S-100 evidenciou as células de Langerhans. Na pele lesada, os melanócitos estavam ausentes ou diminuídos quando comparados com a pele normal. A proteína S-100 demonstrou maior número de células de Langerhans, o que é característico das lesões de vitiligo. CONCLUSÃO: A imuno-histoquímica pode ser utilizada como método auxiliar no diagnóstico dos casos duvidosos de vitiligo.

Clinical presentation of tuberculoid leprosy in an epidermodysplasia verruciformis patient

Epidermodysplasia verruciformis (EV) is triggered by a variety of mechanisms that at least partly include genetic background. We present a Brazilian man with a 30-year history of flat, wart-like lesions with clinical, histopathological, and evolutive aspects consistent with papillomavirus (HPV)-associated EV. Histological analysis of the wart lesions showed epidermis with hyperkeratosis, regular acanthosis, hypergranulosis, and cells with abundant basophilic cytoplasm. Moreover, a perivascular lymphocytic infiltrate was found in the superficial dermis, consistent with a viral wart. Type-2-HPV DNA was detected in various fragments of skin-wart lesions using the polymerase chain reaction (PCR). Two years after the EV diagnosis, the patient presented with an anesthetic well-demarcated, erythematous and mildly scaly plaque on his right forearm. A histopathological analysis of this lesion demonstrated the presence of a compact tuberculoid granuloma. Ziehl-Neelsen staining demonstrated the presence of rare acid-fast bacilli and confirmed the tuberculoid leprosy diagnosis. The patient's Mitsuda Intradermal Reaction was positive. To elucidate the possible mechanism involved in this case of EV, we genotyped the HLA genes of this patient. DQB genotyping showed the polymorphic HLA alleles DQB1*0301 and 0501. The patient was treated with a paucibacillary multidrug therapy scheme, and the disease was cured in six months. This report describes an EV patient with an M. leprae infection, confirming that tuberculoid leprosy patients possess a relatively specific and efficient cell-mediated immunity against the bacillus and, therefore, localized forms of the disease. Moreover, we show the possible involvement of the polymorphic HLA alleles DQB1*0301 and 0501 in EV induction mechanisms.

Lipoma do cerebelo: relato de caso

Lipomas intracranianos são raros, geralmente sendo achado de autópsia. Situam-se na linha média, mais frequentemente de localização central. Podem ocorrer desde a infância até a vida adulta. Muitos dos lipomas, na verdade são associados a lesões hamartomatosas ou, mesmo, a neoplasias como os meduloblastomas do cerebelo. Relatamos e discutimos um caso de lipoma de cerebelo, achado de autópsia de um recém-nascido prematuro.

Melanoma tipo animal: relato de dois casos

Dificuldade potencial no diagnóstico histológico de melanomas é a dificuldade em reconhecer variantes pouco frequentes de melanoma. Entre elas, as mais desafiantes incluem exemplos de melanoma desmoplásico, melanoma nevoide, o chamado melanoma de desvio mínimo, melanomas com proeminente síntese de pigmento ou melanoma tipo animal e o nevo azul maligno. Os autores descrevem dois casos de melanoma tipo animal e discute-se a importância do diagnóstico diferencial clinico-histopatológico nesses casos.

Role of ROC1 protein in the control of cyclin D1 protein expression in skin melanomas

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)