Potential for macro and micronutrients extraction from tomato plants with different soil water stresses

Different tomato cultivars may present differentiated water needs, making it indispensable to study water demand. Thus, the objective of this work was to evaluate the influence of six water stresses in the soil on the extraction potential of macro and micronutrients in the aerial part of tomato in vegetative stage, cultivar ‘Dominador’ F1, under protected cultivation and drip. The experiment was installed in a greenhouse with a randomized block design with four replications. The treatments consisted of six soil water stresses as indicative of the time of irrigation. The preset stresses were 20, 45, 70, 95, 120 and 145 kPa at 20 cm depth. At 140 days after transplanting, the variables evaluated were: the macro and micronutrient content of shoots. The results showed that to obtain higher levels of macro (P and S) and micronutrients (B and Cu) of the total aerial part of the ‘Dominador’ tomato plant F1, it was obtained at a voltage of 20 kPa, and its value was reduced linearly with the increase of the water tension in the soil

Indicadores de qualidade do solo em sistemas de cultivo orgânico e convencional no semi-árido Cearense.

A qualidade do solo pode mudar com o passar do tempo, em decorrência de eventos naturais ou ações antrópicas. A adoção de práticas de cultivo orgânico reduz o revolvimento do solo, favorecendo a recuperação de suas propriedades físicas e químicas. Este trabalho teve como objetivo comparar propriedades físicas,químicas e biológicas de solos cultivados com algodão em bases orgânicas e no sistema convencional, assim como identificar as que possam ser utilizadas como indicadores de qualidade do solo. Selecionaram-se seis áreas submetidas ao cultivo orgânico e três ao cultivo convencional para coleta de amostras de solo deformadas e indeformadas, nas camadas de 0–10, 10–20 e 20–30 cm. Técnicas de estatística univariada e multivariada foram utilizadas para análise dos dados. Os resultados mostraram que os indicadores físicos e químicos testados individualmente não foram sensíveis para diferenciar as áreas sob sistema de cultivo orgânico daquelas sob cultivo convencional. No entanto, a aplicação de técnicas de análise multivariada – no caso, componentes principais e a discriminante de Anderson – permitiu a distinção entre algumas áreas cultivadas sob cultivo orgânico comparativamente às convencionais, até mesmo as que estavam em transição.Dos indicadores biológicos, a fauna edáfica mostrou-se mais precisa na avaliação da qualidade do solo, distinguindo de forma satisfatória as áreas sob sistema de cultivo orgânico das que estavam sob sistema convencional

Problemas productivos y reproductivos por deficiencias minerales en bovinos de algunas regiones tropicales de México

Los minerales son considerados nutrientes esenciales para el organismo. En las zonas tropicales de México, se presenta una problemática de calidad de los forrajes, su contenido de proteína y aporte de minerales son bajos. Las condiciones climáticas influyen en el contenido de minerales en el suelo, plantas y en los animales. Se reportan bajos contenidos de Ca, P, Zn, Se, I y Cu, en la relación suelo-planta-animal. La presencia de algunas enfermedades carenciales se refleja con baja producción de leche y carne, hay efectos negativos en la fertilidad, abortos, baja calidad de semen, retención de placenta, partos distócicos, entre otros. Es importante suplementar los minerales carenciales en el ganado, con el propósito de mejorar la eficiencia productiva. Se debe evitar el exceso de minerales para prevenir efectos contaminantes al ambient

Higgs Boson Decay into Hadronic Jets

The remarkable agreement of electroweak data with standard model (SM) predictions motivates the study of extensions of the SM in which the Higgs boson is light and couples in a standard way to the weak gauge bosons. Postulated new light particles should have small couplings to the gauge bosons. Within this context it is natural to assume that the branching fractions of the light SM-like Higgs boson mimic those in the standard model. This assumption may be unwarranted, however, if there are non-standard light particles coupled weakly to the gauge bosons but strongly to the Higgs field. In particular, the Higgs boson may effectively decay into hadronic jets, possibly without important bottom or charm flavor content. As an example, we present a simple extension of the SM, in which the predominant decay of the Higgs boson occurs into a pair of light bottom squarks that, in turn, manifest themselves as hadronic jets. Discovery of the Higgs boson remains possible at an electron-positron linear collider, but prospects at hadron colliders are diminished substantially.Comment: 30 pages, 7 figure

Theory and phenomenology of two-Higgs-doublet models

We discuss theoretical and phenomenological aspects of two-Higgs-doublet extensions of the Standard Model. In general, these extensions have scalar mediated flavour changing neutral currents which are strongly constrained by experiment. Various strategies are discussed to control these flavour changing scalar currents and their phenomenological consequences are analysed. In particular, scenarios with natural flavour conservation are investigated, including the so-called type I and type II models as well as lepton-specific and inert models. Type III models are then discussed, where scalar flavour changing neutral currents are present at tree level, but are suppressed by either specific ansatze for the Yukawa couplings or by the introduction of family symmetries. We also consider the phenomenology of charged scalars in these models. Next we turn to the role of symmetries in the scalar sector. We discuss the six symmetry-constrained scalar potentials and their extension into the fermion sector. The vacuum structure of the scalar potential is analysed, including a study of the vacuum stability conditions on the potential and its renormalization-group improvement. The stability of the tree level minimum of the scalar potential in connection with electric charge conservation and its behaviour under CP is analysed. The question of CP violation is addressed in detail, including the cases of explicit CP violation and spontaneous CP violation. We present a detailed study of weak basis invariants which are odd under CP. A careful study of spontaneous CP violation is presented, including an analysis of the conditions which have to be satisfied in order for a vacuum to violate CP. We present minimal models of CP violation where the vacuum phase is sufficient to generate a complex CKM matrix, which is at present a requirement for any realistic model of spontaneous CP violation.Comment: v3: 180 pages, 506 references, new chapter 7 with recent LHC results; referee comments taken into account; submitted to Physics Report

Características de la carne de conejo y su vida de anaquel valorada con el perfil de aminas biogénica

En América latina, México tiene el primer lugar en producción de carne de conejo, principalmente el 95% se produce en  pequeña escala, el otro 5% es por empresas. La carne de conejo acumula menos grasa (3 a 6 %) y contiene de 19 a 26 % de proteína. La carne es inaceptable para el consumidor cuando hay cambios físicos en el color, olor, textura y oxidación de lípidos, durante la descomposición se forman aminas biogénicas (AB), éstas son bases orgánicas de bajo peso molecular, caracterizadas por la presencia de un grupo amina. Las principales AB son Putresina, cadaverina, histamina y tiramina. La cromatografía liquida de alta resolución es una técnica confiable para la detección de las AB. Se realizó un estudio con 3 grupos de carne (Longissimus thoracis et lumborum): 1) grupo testigo (T), envasadas en bolsa de plástico, 2) Con empaque semipermeable (ES) y 3) Con empaque al vacío (EV), estas se conservaron en refrigeración, durante 4 tiempos de almacenamiento: Cero (menos de 12 horas de refrigeración), 7, 14 y 21 días. La putrescina incrementó drásticamente (P <0.05) desde los 7 a 21d de almacenamiento. Todos los empaques presentaron un incremento de histamina conforme pasaron los días de almacenamiento.  El tipo de empaque y el tiempo de refrigeración influyeron en la concentración de AB; principalmente el EV tuvo la más baja concentración de putrescina hasta los 21 días de almacenamiento