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The authors wish to make the following corrections to this paper [1]: replace: (37) 1 ε z = f ε m = 1 - f ε d and (39) 1 µ z = f µ m = 1 - f µ d with the correct expressions: (37) 1 ε z = f ε m + 1 - f ε d and (39) 1 µ z = f µ m + 1 - f µ d [...].

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BACKGROUND: Blueberries are among the fruits with the highest antioxidant activity and have been recognized by their health promoting properties. AIM: In vitro study of the anti-proliferative effects of a blueberry extract on a panel of cancer cells from different origin. MATERIALS AND METHODS: A blueberry extract was produced using ethanol as extracting solvent. The anti-proliferative activity of the extract was evaluated against seven tumor cell lines. The properties of blueberry extract to decrease cell adhesion and migration were also investigated. RESULTS: Blueberry extract showed a dose-dependent inhibitory effect on cell proliferation for all cell lines. Non-cytotoxic concentrations of the extract decreased cell adhesion in five of seven cell lines studied and inhibited the migration of MDA-MB-231 and PC-3 tumor cells. CONCLUSION: This work provides additional evidence regarding the ability of blueberry extract to inhibit the growth and decrease cell adhesion and migration of different cancer cell lines in vitro.

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A homogenization theory that can go beyond the regime of long wavelengths is proposed, namely, a theory that is still valid for vectors of waves near the edge of the first zone of Brillouin. In this paper, we consider that the displacement vector and the magnetic induction fields have averages in the volume of the cell associated with the values of the electric and magnetic fields in the edges of the cell, so they satisfy Maxwell's equations. Applying Fourier formalism, explicit expressions were obtained for the case of a photonic crystal with arbitrary periodicity. In the case of one-dimensional (1D) photonic crystals, the expressions for the tensor of the effective bianisotropic response (effective permittivity, permeability and crossed magneto-electric tensors) are remarkably simplified. Specifically, the effective permittivity and permeability tensors are calculated for the case of 1D photonic crystals with isotropic and anisotropic magnetic inclusions. Through a numerical calculation, the dependence of these effective tensors upon the filling fraction of the magnetic inclusion is shown and analyzed. Our results show good correspondence with the approach solution of Rytov's effective medium. The derived formulas can be very useful for the design of anisotropic systems with specific optical properties that exhibit metamaterial behavior.

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Climate change is recognized as an important threat to global biodiversity because it increases the risk of extinction of many species on the planet. Mexico is a megadiverse country and native tree species such as red cedar (Cedrela odorata) can be used to maintain forests while helping mitigate climate change, because it is considered a fast growing pioneer species with great economic potential in the forestry industry. In order to assess possible shifts in areas suitable for C. odorata plantations in Mexico with ecological niche models, we used the MaxLike algorithm, climate variables, the geo-referenced records of this species, three general circulation models and three scenarios of future emissions. Results show a current potential distribution of 573,079 km2 with an average probability of occurrence of 0.93 (± 0.13). The potential distribution area could increase up to 650,356 km2 by 2060 according to the general circulation model HADCM3 B2, with an average probability of occurrence of 0.86 (± 0.14). Finally, we delimited an area of 35,377 km2 that has a high potential for the establishment of C. odorata plantations, by selecting those sites with optimal conditions for its growth that are outside protected areas and are currently devoid of trees. C. odorata has a significant potential to help in the mitigation of the effects of climate change. Using MaxLike we identified extense areas in Mexico suitable to increase carbon sequestration through plantations of this highly valued native tree species.

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Site-specific recombination technologies are powerful new tools for the manipulation of genomic DNA in insects that can improve transgenesis strategies such as targeting transgene insertions, allowing transgene cassette exchange and DNA mobilization for transgene stabilization. However, understanding the fitness cost implications of these manipulations for transgenic strain applications is critical. In this study independent piggyBac-mediated attP target-sites marked with DsRed were created in several genomic positions in the Mexican fruit fly, Anastrepha ludens. Two of these strains, one having an autosomal (attP_F7) and the other a Y-linked (attP_2-M6y) integration, exhibited fitness parameters (dynamic demography and sexual competitiveness) similar to wild type flies. These strains were thus selected for targeted insertion using, for the first time in mexfly, the phiC31-integrase recombination system to insert an additional EGFP-marked transgene to determine its effect on host strain fitness. Fitness tests showed that the integration event in the int_2-M6y recombinant strain had no significant effect, while the int_F7 recombinant strain exhibited significantly lower fitness relative to the original attP_F7 target-site host strain. These results indicate that while targeted transgene integrations can be achieved without an additional fitness cost, at some genomic positions insertion of additional DNA into a previously integrated transgene can have a significant negative effect. Thus, for targeted transgene insertions fitness costs must be evaluated both previous to and subsequent to new site-specific insertions in the target-site strain.

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Ethanolic extracts from Magnolia dealbata (Zucc.) (Magnoliaceae); leaves, bark, seeds, sarcotesta and flowers were evaluated for insecticidal activity against adults of the Mexican fruit fly, Anastrepha ludens (Loew) (Diptera: Tephritidae). Using feeding bioassays composed from sugar-extract mixtures, only the extract from sarcotesta indicated insecticidal activity against the flies. The extracts from the other four plant tissues (leaves, bark, seeds and flowers) did not manifest any biological activity. The most effective extract was obtained from oven-dried sarcotesta, whereas extracts from fresh sarcotesta were inactive. Our results suggest that M. dealbata sarcotesta contains secondary metabolites with insecticidal activity against A. ludens adults. These metabolites are as potent as natural pyrethins and represent a potential substance for controlling this type of pest.

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It has become clear that native species are incorporated naturally under the canopy of many tree plantations. This process of incorporation (facilitation) can be used as an opportunity to create successional models in restoration and species reintroduction projects. The need to incorporate basic ecological information is a critical issue in the process of ecosystem restoration. Pinus is a genus widely used in plantations worldwide. In Mexico, 199 790.4ha are planted with pine each year. Many of these plantations have been established with rehabilitation and conservation goals, and provide an opportunity for restoration through the reintroduction of native species of plants and animals. Because pine species are considered as pioneers in forest successional stages, pine plantations represent natural laboratories that can be used to test scientific hypothesis to strengthen the restoration and reintroduction programs. These plantations also represent an opportunity to apply scientific knowledge in practical field conservation and address the science-policy interface. In this essay, we presented arguments focused on the importance of plantations as areas for experimentation, given the diversity of environments in which they are found, from sea level to high altitudes, as well as the diversity in their structure and composition.

Se ha evidenciado que bajo el dosel de muchas plantaciones forestales se incorporan, de manera natural, especies nativas. Este proceso de incorporación (facilitación), puede ser usado como una oportunidad para crear modelos sucesionales en proyectos de restauración y reintroducción de especies. La necesidad de incorporar información ecológica básica es una cuestión crítica en el proceso de restauración de ecosistemas. Pinus es un género ampliamente usado en plantaciones a nivel mundial. En México, las plantaciones de pino representan 199 790,4ha al año. Muchas de éstas se han establecido con objetivos de rehabilitación y conservación, y constituyen una oportunidad para la restauración a partir de la reintroducción de especies de plantas y animales nativos. Debido a que los pinos son considerados como especies pioneras de la sucesión, las plantaciones de pino representan laboratorios naturales que nos permiten invalidar hipótesis científicas para fortalecer programas de restauración o reintroducción de especies. Estas plantaciones también representan una oportunidad para aplicar el conocimiento científico en la práctica de la conservación de campo y atender la interfase política-sociedad. En el presente ensayo presentamos argumentos enfocados hacia la importancia que las plantaciones tienen como áreas de experimentación dada la diversidad de ambientes en las que se encuentran, desde el nivel del mar hasta las grandes altitudes, así como de estructura y composición de las mismas.

Tem-se evidenciado que sob o dossel de muitas plantações florestais se incorporam, de maneira natural, espécies nativas. Este processo de incorporação (facilitação), pode ser usado como uma oportunidade para criar modelos sucessionais em projetos de restauração e reintrodução de espécies. A necessidade de incorporar informação ecológica básica é uma questão crítica no processo de restauração de ecossistemas. Pinus é um gênero amplamente usado em plantações a nível mundial. No México, as plantações de pinheiros representam 199.790,4 ha ao ano. Muitas destas foram estabelecidas com objetivos de reabilitação e conservação, e constituem uma oportunidade para a restauração apartir da reintrodução de espécies de plantas e animais nativos. Devido a que os pinheiros são considerados como espécies pioneiras da sucessão, as plantações de pinheiros representam laboratórios naturais que nos permitem invalidar hipóteses científicas para fortalecer programas de restauração ou reintrodução de espécies. Estas plantações também representam uma oportunidade para aplicar o conhecimento científico na prática da conservação de campo e atender a interfase política-sociedade. No presente ensaio apresentamos argumentos focados para a importância que as plantações têm como áreas de experimentação devido à diversidade de ambientes em que se encontram, do nível do mar até as grandes altitudes, assim como de estrutura e composição das mesmas.

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Little is known about the ecology and demography of the genus Magnolia. Magnolia dealbata Zucc. is an endangered species endemic to Mexico. Two contrasting populations of M. dealbata (one from the grasslands and other from a secondary cloud forest) were studied. We asked the following questions: (a) Are size structure (diameter at breast height, DBH) and infrutescence production significantly different between the two populations? (b) What are the populations' growth rates (lambda) based on an initial 1987 study? (c) Are the associated species diversity indices of these M. dealbata populations significantly different? The results show no significant differences between the population size structure (p=.094); the growth rates of the populations were 0.992 in grassland and 1.053 in secondary cloud forest. The number of infrutescences produced in year 2001 and DBH relationship were significantly linear (p<.001) in both populations, and there was no significant difference (p>.01) between their slopes. The diversity indices were not significantly different (p>.05), and only 54% of the species were common to both sites. Our study suggests that both populations are relatively stable and that the management history could impact more on the species composition than on the diversity indices.

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Se estudiaron los 32 pacientes fallecidos en los Hospitales Provinciales Clínico Quirúrgico Docente y Pediátrico de Sancti Spíritus, con el diagnóstico de epilepsia, en el quinquenio 1986-1990, lo cual representa el 0,73 % del total de defunciones. Para ello fueron revisadas las historias clínicas, protocolos de necropsias y certificados de defunción. La mayor frecuencia fue del sexo masculino. Las crisis convulsivas y la fiebre constituyeron el motivo de ingreso más frecuente. Las crisis convulsivas de carácter generalizado predominaron, así como el tiempo de evolución de la epilepsia menor de un año. Las complicaciones en relación directa con la muerte más frecuentes, fueron el estatus convulsivo, la bronconeumonía y la hipertensión intracraneal. Los hallazgos necrópsicos más relevantes fueron el edema cerebral y la bronconeumonía. El certificado de defunción no refleja en la mayoría de los casos el diagnóstico de epilepsia

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Se realiza un estudio descriptivo, en el que se recogen los diversos criterios de los alumnos de 5to año de la carrera de medicina que cursan la estancia de la asignatura Salud Pública en la Facultad de Ciencias Médicas de Sancti Spíritus, durante el curso escolar de 1998-1999. Se aplicó una encuesta anónima entre todos estos estudiantes y se obtienen como resultados finales que la Administración de Salud presenta dificultades en el desarrollo de la rotación y que no existe una motivación adecuada sobre la asignatura; sobre todo por la temática de administración de salud.

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Um cäo, da raça Cocker Spaniel, de 10 anos de idade, com 11,3kg, foi atendido no Hospital Veterinário da UFMG, apresentando ao exame clínico, tenesmo, disúria e dificuldade de locomoçäo dos membros posteriores. A palpaçäo abdominal caudal e toque retal, observou-se ainda sensibilidade dolorosa na regiäo prostática com discreto aumento da glândula. Para o diagnóstico de prováveis patologias prostáticas, foram realizados os seguintes exames: urinálise, radiologia, ultra-sonografia, citologia, histopatologia e análise físico-química. O diagnóstico foi de cálculo prostático associado à hiperplasia e prostatite crônica

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Se estudian 52 pacientes con púrpura anafilactoide (síndrome de Schönlein-Henoch), y se destaca una incidencia similar en uno y otro sexos y predominio de presentación en los meses invernales. Se informa que las manifestaciones clínicas y de laboratorio fueron: lesiones cutáneas en el 100%, artralgias en el 61,5%, dolor abdominal en el 44,3%, artritis en el 32,7%, fiebre de más de 38-C en el 21,1%, hematuria microscópica en el 19,2%, hematuria macroscópica en el 17,3%, proteinuria dosificable en el 15,4%, anterorragia en el 11,5% melena en el 3,8% y hematemesis; insuficiencia cardíaca, hipocomplementemia transitorio o hipertensión arterial en el 1,9% respectivamente. Se detecta afectación renal en el 35% de los pacientes. Se aísla en el 46% estreptococo beta-hemolítico en el exudado faríngeo y en el 77%, un título de antiestreptolisina o (TASO) elevado. Se señala que las lesiones encontradas en la biopsia renal incluyen: Lesión mínima, glomerulonefritis segmentaria y focal, glomerulonefritis proliferativa difusa sin crecientes epiteliales y glomerulonefritis proliferativa difusa con crecientes epiteliales aisladas. Quince pacientes (29%) reingresaron, 13 por púrpura recurrente (25,2%) y 2 (3,8%) por alteraciones en el sedimento urinario. Se repite a estos últimos la biopsia renal y se demuestra en el deterioro hístico. No se demuestra afectación renal en las púrpuras recurrentes

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We report five patients with Myxomas of the left atrium studied by catheterization and/or Echocardiography between november 1976 and october 1978. Four patients were operated immediately with extracorporeal circulation which confirmed the diagnosis. The last patient died before surgical intervention due to a severe hepatorenal syndrome and extensive pulmonary infection. Another patient died postoperatively on the second day due to irreversible pulmonary hypertensión. The remaining three patients are asymptomatic (average 28 months after surgery). Reviewing the diagnostic methods, particularly the Echocardiogram, we found that it is a good diagnostic tool, making catheterization with the risks of myxomatous embolization unnecessary. Furthermore, the Echo facilitates simple and economic observation for the detection of relapses. Finally, broad and careful surgical management most be emphasized in order to avoid transoperative emboli, tumoral dissemination, and latent relapses, mediated by the greater use of filters and a broad resection of the implantation pedicule.

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