Caracterización de tetraploides y formación de híbridos triploides en tomate de cáscara

RESUMEN El tomatillo (Physalis ixocarpa Brot.) es de los cultivos hortícolas más importantes de México, aunque presenta rendimientos bajos, debido a que su autoincompatibilidad impide la formación de líneas puras e híbridos. La formación de poliploides sobresalientes de tomatillo es una alternativa para aumentar rendimientos y calidad de fruto. En este trabajo se encontraron diferencias significativas (p<0.01) entre diploides y tetraploides para RTF, NF, PPF, DPF, DEF, FIR, SST, pH y VC. Los híbridos triploides, 2Tx13D y 11Tx21D mostraron heterosis y heterobeltiosis en todas las variables estudiadas. En rendimiento, el triploide 2Tx13D superó en 178.24% al 2T y 19.66% al 13D, el 11Tx21D superó en 145.76% y 0.39% al tetraploide y diploide, respectivamente. ABSTRACT The tomatillo (Physalis ixocarpa Brot.) is of major horticultural crops of Mexico, although it has low yields because your self-incompatibility prevents the formation of pure lines and hybrids. The polyploids formation outstanding of tomatillo, are an alternative to increase yields and fruit quality. In this work, was showed significant differences (p<0.01) between diploid and tetraploid in RTF, NF, PPF, DPF, DEF, FIR, TSS, pH and VC. Triploid hybrids 11Tx21D and 2Tx13D they showed heterosis and heterobeltiosis in all the variables studied. In yield, the triploid hybrid, 2Tx13D exceeded in 178.24% and 19.66% to parents 2T and 13D, meanwhile the hybrid 11Tx21D exceeded to the diploid and tetraploid in 0.39% and 145.76% respectively

The Lie derivative of spinor fields: theory and applications

Starting from the general concept of a Lie derivative of an arbitrary differentiable map, we develop a systematic theory of Lie differentiation in the framework of reductive G-structures P on a principal bundle Q. It is shown that these structures admit a canonical decomposition of the pull-back vector bundle i_P^*(TQ) = P\times_Q TQ over P. For classical G-structures, i.e. reductive G-subbundles of the linear frame bundle, such a decomposition defines an infinitesimal canonical lift. This lift extends to a prolongation Gamma-structure on P. In this general geometric framework the concept of a Lie derivative of spinor fields is reviewed. On specializing to the case of the Kosmann lift, we recover Kosmann's original definition. We also show that in the case of a reductive G-structure one can introduce a "reductive Lie derivative" with respect to a certain class of generalized infinitesimal automorphisms, and, as an interesting by-product, prove a result due to Bourguignon and Gauduchon in a more general manner. Next, we give a new characterization as well as a generalization of the Killing equation, and propose a geometric reinterpretation of Penrose's Lie derivative of "spinor fields". Finally, we present an important application of the theory of the Lie derivative of spinor fields to the calculus of variations.Comment: 28 pages, 1 figur

Two-spinor Formulation of First Order Gravity coupled to Dirac Fields

Two-spinor formalism for Einstein Lagrangian is developed. The gravitational field is regarded as a composite object derived from soldering forms. Our formalism is geometrically and globally well-defined and may be used in virtually any 4m-dimensional manifold with arbitrary signature as well as without any stringent topological requirement on space-time, such as parallelizability. Interactions and feedbacks between gravity and spinor fields are considered. As is well known, the Hilbert-Einstein Lagrangian is second order also when expressed in terms of soldering forms. A covariant splitting is then analysed leading to a first order Lagrangian which is recognized to play a fundamental role in the theory of conserved quantities. The splitting and thence the first order Lagrangian depend on a reference spin connection which is physically interpreted as setting the zero level for conserved quantities. A complete and detailed treatment of conserved quantities is then presented.Comment: 16 pages, Plain TE

Colorectal cancer after bariatric surgery (Cric-Abs 2020): Sicob (Italian society of obesity surgery) endorsed national survey

Background The published colorectal cancer (CRC) outcomes after bariatric surgery (BS) are conflicting, with some anecdotal studies reporting increased risks. The present nationwide survey CRIC-ABS 2020 (Colo-Rectal Cancer Incidence-After Bariatric Surgery-2020), endorsed by the Italian Society of Obesity Surgery (SICOB), aims to report its incidence in Italy after BS, comparing the two commonest laparoscopic procedures-Sleeve Gastrectomy (SG) and Roux-en-Y gastric bypass (GBP). Methods Two online questionnaires-first having 11 questions on SG/GBP frequency with a follow-up of 5-10 years, and the second containing 15 questions on CRC incidence and management, were administered to 53 referral bariatric, high volume centers. A standardized incidence ratio (SIR-a ratio of the observed number of cases to the expected number) with 95% confidence intervals (CI) was calculated along with CRC incidence risk computation for baseline characteristics. Results Data for 20,571 patients from 34 (63%) centers between 2010 and 2015 were collected, of which 14,431 had SG (70%) and 6140 GBP (30%). 22 patients (0.10%, mean age = 53 +/- 12 years, 13 males), SG: 12 and GBP: 10, developed CRC after 4.3 +/- 2.3 years. Overall incidence was higher among males for both groups (SG: 0.15% vs 0.05%; GBP: 0.35% vs 0.09%) and the GBP cohort having slightly older patients. The right colon was most affected (n = 13) and SIR categorized/sex had fewer values &lt; 1, except for GBP males (SIR = 1.07). Conclusion Low CRC incidence after BS at 10 years (0.10%), and no difference between procedures was seen, suggesting that BS does not trigger the neoplasm development

Metric-affine gravity and the Nester-Witten 2-form

In this paper we redefine the well-known metric-affine Hilbert Lagrangian in terms of a spin connection and a spin-tetrad. On applying the Poincaré–Cartan method and using the geometry of gauge-natural bundles, a global gravitational superpotential is derived. On specializing to the case of the Kosmann lift, we recover the result originally found by Kijowski [Gen. Rel. Gravity 9 (1978) (10) 857] for the metric (natural) Hilbert Lagrangian. On choosing a different, suitable lift, we can also recover the Nester–Witten 2-form, which plays an important role in the energy positivity proof and in many quasi-local definitions of mass