Soil characteristics and abundance of archaea in samples from the Ross Sea Region, Antarctica

The objective of this study was to examine the presence and diversity of Archaea within mineral and ornithogenic soils from 12 locations across the Ross Sea region. Archaea were not abundant but DNA sufficient for producing 16S rRNA gene clone libraries was extracted from 18 of 51 soil samples, from four locations. A total of 1452 clones were analysed by restriction fragment length polymorphism and assigned to 43 operational taxonomic units from which representatives were sequenced. Archaea were primarily restricted to coastal mineral soils which showed a predominance of Crenarchaeota belonging to group 1.1b (>99% of clones). These clones were assigned to six clusters (A through F), based on shared identity to sequences in the GenBank database. Ordination indicated that soil chemistry and water content determined archaeal community structure. This is the first comprehensive study of the archaeal community in Antarctic soils and as such provides a reference point for further investigation of microbial function in this environment.

La influencia de la natación en el fortalecimiento de la autoestima en niños de 4-7 años en el I. P. N.

La investigación esta enmarcada desde la Educación de Física y la Psicología, tomando como punto de partida las Actividades Acuáticas Educativas (Moreno y Gutiérrez) dentro de la natación y la autoestima como elemento fundamental en la construcción y desarrollo del niño, se busca determinar si la natación influye en el fortalecimiento de la autoestima en niños de 4-7 años, con el fin de teorizar sobre estos constructos. Objetivo general: Determinar si la natación influye en el fortalecimiento de la autoestima en niños de 4-7 años en el I.P.N., con el fin de teorizar acerca de la influencia de la práctica de la natación en el desarrollo de la autoestima. Objetivos específicos: Construir conceptos, categorías y proposiciones emergentes de la investigación con el fin de teorizar en torno a la práctica de la natación y su relación con el desarrollo de la autoestima. Metodología empleada. El enfoque metodológico para esta investigación es el cualitativo-crítico que trata de transcender las barreras entre lo cualitativo y lo cuantitativo, buscando dar una interpretación intersubjetiva, verificable en una realidad específica, con el fin de construir un conocimiento dialógico que complemente datos estadísticos con interpretaciones y análisis de contenido cualitativo, para nuestra investigación se utiliza como diseño metodológico la teoría fundamentada. La población total fue de 434 sujetos sus edades oscilan entre los 4 - 7 años, niños escolarizados del Instituto Pedagógico Nacional de los grados J1, J2, J3, J4, J5, T1,T2, T3, T4,T5, 101, 102, 103, 104, y 105. La investigación logro evidenciar que la práctica de la natación y específicamente con fines de actividades acuáticas educativas, logran fortalecer no solo la autoestima si no también el autoconcepto siendo estas dos premisas fundamentales en el desarrollo de los niños de 4 a 7 años y que se desarrollan de forma paralela. Teniendo en cuenta que además de ser la autoestima la evaluación de sí mismo es el valor o valoración que cada persona hace de sí mismo considerando sus virtudes y dimensionando en su justa medida los defectos. Es importante enfatizar que los resultados obtenidos son un aproximación al tema en estudio y por tanto no son generalizables.Desde esta perspectiva teórica, el estudio de la influencia de la natación en el fortalecimiento del autoestima y el autoconcepto en niños de 4 a 7 años aporta una acercamiento a un campo poco explorado, en donde se busca dejar antecedentes que sirvan para futuras investigaciones para niños de 8 años en adelante, considerando la evolución del desarrollo de la autoestima y el autoconcepto según la edad y que permitan fortalecer los espacios de actividades complementarias como la natación y a su vez abrir una mirada totalmente diferente de los maestros en donde su función pedagógica busque transcender más allá del aula de clase

La influencia de la natación en el fortalecimiento de la autoestima en niños de 4-7 años en el I. P. N.

La investigación esta enmarcada desde la Educación de Física y la Psicología, tomando como punto de partida las Actividades Acuáticas Educativas (Moreno y Gutiérrez) dentro de la natación y la autoestima como elemento fundamental en la construcción y desarrollo del niño, se busca determinar si la natación influye en el fortalecimiento de la autoestima en niños de 4-7 años, con el fin de teorizar sobre estos constructos. Objetivo general: Determinar si la natación influye en el fortalecimiento de la autoestima en niños de 4-7 años en el I.P.N., con el fin de teorizar acerca de la influencia de la práctica de la natación en el desarrollo de la autoestima. Objetivos específicos: Construir conceptos, categorías y proposiciones emergentes de la investigación con el fin de teorizar en torno a la práctica de la natación y su relación con el desarrollo de la autoestima. Metodología empleada. El enfoque metodológico para esta investigación es el cualitativo-crítico que trata de transcender las barreras entre lo cualitativo y lo cuantitativo, buscando dar una interpretación intersubjetiva, verificable en una realidad específica, con el fin de construir un conocimiento dialógico que complemente datos estadísticos con interpretaciones y análisis de contenido cualitativo, para nuestra investigación se utiliza como diseño metodológico la teoría fundamentada. La población total fue de 434 sujetos sus edades oscilan entre los 4 - 7 años, niños escolarizados del Instituto Pedagógico Nacional de los grados J1, J2, J3, J4, J5, T1,T2, T3, T4,T5, 101, 102, 103, 104, y 105. La investigación logro evidenciar que la práctica de la natación y específicamente con fines de actividades acuáticas educativas, logran fortalecer no solo la autoestima si no también el autoconcepto siendo estas dos premisas fundamentales en el desarrollo de los niños de 4 a 7 años y que se desarrollan de forma paralela. Teniendo en cuenta que además de ser la autoestima la evaluación de sí mismo es el valor o valoración que cada persona hace de sí mismo considerando sus virtudes y dimensionando en su justa medida los defectos. Es importante enfatizar que los resultados obtenidos son un aproximación al tema en estudio y por tanto no son generalizables.Desde esta perspectiva teórica, el estudio de la influencia de la natación en el fortalecimiento del autoestima y el autoconcepto en niños de 4 a 7 años aporta una acercamiento a un campo poco explorado, en donde se busca dejar antecedentes que sirvan para futuras investigaciones para niños de 8 años en adelante, considerando la evolución del desarrollo de la autoestima y el autoconcepto según la edad y que permitan fortalecer los espacios de actividades complementarias como la natación y a su vez abrir una mirada totalmente diferente de los maestros en donde su función pedagógica busque transcender más allá del aula de clase

Examples of PDEs all whose points are characteristic

Let π : FM ! M be the bundle of linear frames of a manifold M. A basis Lijk , j < k, of diffeomorphism invariant Lagrangians on J1 (FM) was determined in [J. Muñoz Masqué, M. E. Rosado, Invariant variational problems on linear frame bundles, J. Phys. A35 (2002) 2013-2036]. The notion of a characteristic hypersurface for an arbitrary first-order PDE system on an ar- bitrary bred manifold π : P → M, is introduced and for the systems dened by the Euler-Lagrange equations of Lijk every hypersurface is shown to be characteristic. The Euler-Lagrange equations of the natural basis of Lagrangian densities Lijk on the bundle of linear frames of a manifold M which are invariant under diffeomorphisms, are shown to be an underdetermined PDEs systems such that every hypersurface of M is characteristic for such equations. This explains why these systems cannot be written in the Cauchy-Kowaleska form, although they are known to be formally integrable by using the tools of geometric theory of partial differential equations, see [J. Muñoz Masqué, M. E. Rosado, Integrability of the eld equations of invariant variational problems on linear frame bundles, J. Geom. Phys. 49 (2004), 119-155]

Identification of active sites in amidase: Evolutionary relationship between amide bond- and peptide bond-cleaving enzymes

Mainly based on various inhibitor studies previously performed, amidases came to be regarded as sulfhydryl enzymes. Not completely satisfied with this generally accepted interpretation, we performed a series of site-directed mutagenesis studies on one particular amidase of Rhodococcus rhodochrous J1 that was involved in its nitrile metabolism. For these experiments, the recombinant amidase was produced as the inclusion body in Escherichia coli to greatly facilitate its recovery and subsequent purification. With regard to the presumptive active site residue Cys203, a Cys203 → Ala mutant enzyme still retained 11.5% of the original specific activity. In sharp contrast, substitutions in certain other positions in the neighborhood of Cys203 had a far more dramatic effect on the amidase. Glutamic acid substitution of Asp191 reduced the specific activity of the mutant enzyme to 1.33% of the wild-type activity. Furthermore, Asp191 → Asn substitution as well as Ser195 → Ala substitution completely abolished the specific activity. It would thus appear that, among various conserved residues residing within the so-called signature sequence common to all amidases, the real active site residues are Asp191 and Ser195 rather than Cys203. Inasmuch as an amide bond (CO-NH2) in the amide substrate is not too far structurally removed from a peptide bond (CO-NH-), the signature sequences of various amidases were compared with the active site sequences of various types of proteases. It was found that aspartic acid and serine residues corresponding to Asp191 and Ser195 of the Rhodococcus amidase are present within the active site sequences of aspartic proteinases, thus suggesting the evolutionary relationship between the two.

Syncytiotrophoblastic giant cells in teratocarcinoma-like tumors derived from Parp-disrupted mouse embryonic stem cells

The enzyme poly(ADP-ribose) polymerase (Parp) catalyzes poly(ADP-ribosyl)ation reaction and is involved in DNA repair and cell death induction upon DNA damages. Meanwhile, poly(ADP-ribosyl)ation of chromosome-associated proteins is suggested to be implicated in the regulation of gene expression and cellular differentiation, both of which are important in tumorigenesis. To investigate directly the role of Parp deficiency in tumorigenicity and differentiation of embryonic stem (ES) cells during tumor formation, studies were conducted by using wild-type J1 (Parp+/+) ES cells and Parp+/− and Parp−/− ES clones generated by disrupting Parp exon 1. These ES cells, irrespective of the Parp genotype, produced tumors phenotypically similar to teratocarcinoma when injected s.c. into nude mice. Remarkably, all tumors derived from Parp−/− clones contained syncytiotrophoblastic giant cells (STGCs), which possess single or multiple megalo-nuclei. The STGCs were present within large areas of intratumoral hemorrhage. In contrast, neither STGC nor hemorrhage was observed in tumors of both wild-type J1 cells and Parp+/− clones. Electron microscopic examination showed that the STGCs possess microvilli on the cell surface and contained secretory granules in the cytoplasm. Furthermore, the cytoplasms of STGCs were strongly stained with antibody against mouse prolactin, which could similarly stain trophoblasts in placenta. These morphological and histochemical features indicate that the STGCs in teratocarcinoma-like tumors derived from Parp−/− clones belong to the trophoblast cell lineage. Our findings thus suggest that differentiation of ES cells into STGCs was possibly induced by the lack of Parp during the development of teratocarcinoma.

Navy directory. Officers of the United States Navy and Marine Corps, also including officers of the U.S. Naval Reserve Force, Marine Corps Reserve, Coast Guard, Coast and Geodetic Survey, Public Health Service, and foreign officers serving with the Navy.

Suspended J1.1, 1921-Jan. 1, 1922.

Petrohol (isopropyl alcohol) : uses, properties, and analysis.

Bibliography: p. J1-J12.

Archaeal diversity in two thermophilic chalcopyrite bioleaching reactors

This study used a culture-independent molecular approach to investigate the archaeal community composition of thermophilic bioleaching reactors. Two culture samples, MTC-A and MTC-B, grown with different concentrations of chalcopyrite (CuFeS2), a copper sulfidic ore, at a temperature of 78 degrees C and pH 1.6 were studied. Phylogenetic analysis of the 16S rRNA genes revealed that both cultures consisted of Archaea belonging to the Sulfolobales. The 16S rRNA gene clone library of MTC-A grown with 4% (w/v) chalcopyrite was dominated by a unique phylotype related to Sulfolobus shibatae (69% of total clones). The remaining clones were affiliated with Stygiolobus azoricus (11%), Metallosphaera sp. J1 (8%), Acidianus infernus (2%), and a novel phylotype related to Sulfurisphaera ohwakuensis (10%). In contrast, the clones from MTC-B grown with 12% (w/v) chalcopyrite did not appear to contain Sulfolobus shibatae-like organisms. Instead the bioleaching consortium was dominated by clones related to Sulfurisphaera ohwakuensis (73.9% of total clones). The remaining microorganisms detected were similar to those found in MTC-A.

Clinical utility of the KAMRA corneal inlay

The treatment of presbyopia has been the focus of much scientific and clinical research over recent years, not least due to an increasingly aging population but also the desire for spectacle independence. Many lens and nonlens-based approaches have been investigated, and with advances in biomaterials and improved surgical methods, removable corneal inlays have been developed. One such development is the KAMRA™ inlay where a small entrance pupil is exploited to create a pinhole-type effect that increases the depth of focus and enables improvement in near visual acuity. Short- and long-term clinical studies have all reported significant improvement in near and intermediate vision compared to preoperative measures following monocular implantation (nondominant eye), with a large proportion of patients achieving Jaeger (J) 2 to J1 (~0.00 logMAR to ~0.10 logMAR) at the final follow-up. Although distance acuity is reduced slightly in the treated eye, binocular visual acuity and function remain very good (mean 0.10 logMAR or better). The safety of the inlay is well established and easily removable, and although some patients have developed corneal changes, these are clinically insignificant and the incidence appears to reduce markedly with advancements in KAMRA design, implantation technique, and femtosecond laser technology. This review aims to summarize the currently published peer-reviewed studies on the safety and efficacy of the KAMRA inlay and discusses the surgical and clinical outcomes with respect to the patient’s visual function.

The proof of Kontsevich's periodicity conjecture on noncommutative birational transformations

For an arbitrary associative unital ring RR, let J1J1 and J2J2 be the following noncommutative, birational, partly defined involutions on the set M3(R)M3(R) of 3×33×3 matrices over RR: J1(M)=M−1J1(M)=M−1 (the usual matrix inverse) and J2(M)jk=(Mkj)−1J2(M)jk=(Mkj)−1 (the transpose of the Hadamard inverse).

We prove the surprising conjecture by Kontsevich that (J2∘J1)3(J2∘J1)3 is the identity map modulo the DiagL×DiagRDiagL×DiagR action (D1,D2)(M)=D−11MD2(D1,D2)(M)=D1−1MD2 of pairs of invertible diagonal matrices. That is, we show that, for each MM in the domain where (J2∘J1)3(J2∘J1)3 is defined, there are invertible diagonal 3×33×3 matrices D1=D1(M)D1=D1(M) and D2=D2(M)D2=D2(M) such that (J2∘J1)3(M)=D−11MD2(J2∘J1)3(M)=D1−1MD2.

História concisa das linhagens de DNA mitocondrial de uma população de judeus curdos através da análise da sua região controlo

O povo curdo, oriundo do Médio Oriente, é constituído por cerca de 36 milhões de indivíduos, dispersos por quatro países diferentes: a Turquia, o Irão, o Iraque e a Síria. Não obstante as suas diversas origens étnicas, a linguagem e a cultura estão intimamente relacionadas com a população persa (correspondente à região do atual Irão). Neste estudo foi traçado o perfil genético da linhagem materna desta população de que professa a religião judaica através da análise da região controlo do DNA mitocondrial (DNAmt) e, posteriormente, comparado com outras populações da Europa, de África e do Médio Oriente, bem como com demais populações judaicas. Identificou-se uma elevada diversidade genética com a prevalência dos haplogrupos mitocondriais H, J1 e N1, comuns do Médio Oriente. A pesquisa por uma possível relação genética entre esta população de judeus curdos com outras populações relevantes discriminadas na literatura apontou para uma relação mais próxima com as populações da Bulgária, do Irão e do Azerbaijão e com os judeus da mesma região do que com as demais populações do Médio Oriente. Os presentes resultados sugerem que o povo curdo judeu conseguiu manter ao longo do tempo um certo isolamento genético relativamente às influências de populações circundantes.

História concisa das linhagens de DNA mitocondrial de uma população de judeus curdos através da análise da sua região controlo

O povo curdo, oriundo do Médio Oriente, é constituído por cerca de 36 milhões de indivíduos, dispersos por quatro países diferentes: a Turquia, o Irão, o Iraque e a Síria. Não obstante as suas diversas origens étnicas, a linguagem e a cultura estão intimamente relacionadas com a população persa (correspondente à região do atual Irão). Neste estudo foi traçado o perfil genético da linhagem materna desta população de que professa a religião judaica através da análise da região controlo do DNA mitocondrial (DNAmt) e, posteriormente, comparado com outras populações da Europa, de África e do Médio Oriente, bem como com demais populações judaicas. Identificou-se uma elevada diversidade genética com a prevalência dos haplogrupos mitocondriais H, J1 e N1, comuns do Médio Oriente. A pesquisa por uma possível relação genética entre esta população de judeus curdos com outras populações relevantes discriminadas na literatura apontou para uma relação mais próxima com as populações da Bulgária, do Irão e do Azerbaijão e com os judeus da mesma região do que com as demais populações do Médio Oriente. Os presentes resultados sugerem que o povo curdo judeu conseguiu manter ao longo do tempo um certo isolamento genético relativamente às influências de populações circundantes.

Unemployed, Now What? The Effect of Immigration on Unemployment Transitions of Native-born Workers in the United States

Although one would expect the unemployed to be the population most likely affected by immigration, most of the studies have concentrated on investigating the effects immigration has on the employed population. Little is known of the effects of immigration on labor market transitions out of unemployment. Using the basic monthly Current Population Survey from 2001 and 2013 we match data for individuals who were interviewed in two consecutive months and identify workers who transition out of unemployment. We employ a multinomial model to examine the effects of immigration on the transition out of unemployment, using state-level immigration statistics. The results suggest that immigration does not affect the probabilities of native-born workers finding a job. Instead, we find that immigration is associated with smaller probabilities of remaining unemployed, but it is also associated with higher probabilities of workers leaving the labor force. This effect impacts mostly young and less educated people.