1,563 research outputs found
Adubação nitrogenada totalmente na semeadura do trigo.
Os triticultores dispõem de considerável volume de informações para definir a dose de N a ser minitrada na lavoura, contudo, tem havido pouco questionamento sobre o modo de aplicação do fertilizante nitrogenado. O trabalho teve por objetivo avaliar as fontes uréia, uréia+NBPT (inibidor de urease) e nitrato de amônio em diferentes doses aplicadas nos sulcos de semeadura do trigo, em comparação com a adubação de cobertura, em duas condições de cultivo, em regime de sequeiro e irrigado. Foram realizados dois experimentos na safra de 2011, em Ponta Grossa/PR em regime de sequeiro e solo de textura média, e em Londrina/PR com irrigação e solo argiloso, localidades representativas das macrorregiões tritícolas I e III do Paraná, respectivamente. O nitrato de amônio é a fonte mais segura para uso em adubos formulados NPK para a semeadura do trigo. A uréia nos sulcos de semeadura causa forte fitoxicidade à lavoura de trigo, e o inibidor de urease NBPT minimiza tal impacto. A adubação nitrogenada na semeadura do trigo deve contemplar doses de 20 a 40 kg N ha-1. O modo de aplicação do N no trigo, semeadura e/ou cobertura, guarda forte interação com o ambiente de cultivo.Fertbio
Evaluación genética en etapa de vivero de áreas productoras de semillas (APS) de Pino Ponderosa en Nordpatagonia
El Pino Ponderosa (Pinus ponderosa Dougl. ex Laws) es la principal especie forestal implantada en secanoen la Patagonia. Su potencialidad productiva y la disponibilidad de tierras para su cultivo permiten proyectarla continuidad de su uso en plantaciones comerciales, para lo que es indispensable asegurar la provisión desemillas de adecuada calidad genética. Las semillas utilizadas en la última década se produjeron en una seriede rodales mediante ensayos para evaluar su descendencia. El objetivo del presente trabajo es evaluar estosrodales ensayando su descendencia. En este primer reporte presentamos los resultados de una evaluaciónen etapa de vivero. Se ensayaron 31 procedencias locales seleccionadas (Áreas Productoras de Semillas,APS) en dos sitios, midiendo altura y diámetro a la altura del cuello en plantines de 2 años de edad. A través de análisis de la varianza se probó un claro efecto de interacción entre las APS y los sitios, y también diferencias entre las APS dentro de cada sitio. Seguidamente, se establecieron rankings de las APS por sitio y variable evaluada. A través de comparaciones de a pares se formaron grupos homogéneos. También se estimó la estabilidad genotípica de las APS por medio del cálculo de sus ecovalencias. Los resultados son aún preliminares, pero el haber probado diferencias en tan temprana edad nos alerta sobre la importancia de la procedencia de las semillas a utilizar para la producción comercial. Se espera que estas diferencias se acentúen en edades más avanzadas. Para probarlo, ya se han establecido ensayos de plantación
Sepsis Mortality Prediction Based on Predisposition, Infection and Response
OBJECTIVE: To empirically test, based on a large multicenter, multinational database, whether a modified PIRO (predisposition, insult, response, and organ dysfunction) concept could be applied to predict mortality in patients with infection and sepsis.
DESIGN: Substudy of a multicenter multinational cohort study (SAPS 3).
PATIENTS: A total of 2,628 patients with signs of infection or sepsis who stayed in the ICU for >48 h. Three boxes of variables were defined, according to the PIRO concept. Box 1 (Predisposition) contained information about the patient's condition before ICU admission. Box 2 (Injury) contained information about the infection at ICU admission. Box 3 (Response) was defined as the response to the infection, expressed as a Sequential Organ Failure Assessment score after 48 h.
INTERVENTIONS: None.
MAIN MEASUREMENTS AND RESULTS: Most of the infections were community acquired (59.6%); 32.5% were hospital acquired. The median age of the patients was 65 (50-75) years, and 41.1% were female. About 22% (n=576) of the patients presented with infection only, 36.3% (n=953) with signs of sepsis, 23.6% (n=619) with severe sepsis, and 18.3% (n=480) with septic shock. Hospital mortality was 40.6% overall, greater in those with septic shock (52.5%) than in those with infection (34.7%). Several factors related to predisposition, infection and response were associated with hospital mortality.
CONCLUSION: The proposed three-level system, by using objectively defined criteria for risk of mortality in sepsis, could be used by physicians to stratify patients at ICU admission or shortly thereafter, contributing to a better selection of management according to the risk of death
Cancer Rehabilitation Indicators for Europe
Little is known of cancer rehabilitation needs in Europe. EUROCHIP-3 organised a group of experts to propose a list of population-based indicators used for describing cancer rehabilitation across Europe. The aim of this study is to present and discuss these indicators. A EUROCHIP-3 expert panel reached agreement on two types of indicators. (a) Cancer prevalence indicators. These were proposed as a means of characterising the burden of cancer rehabilitation needs by time from diagnosis and patient health status. These indicators can be estimated from cancer registry data or by collecting data on follow-up and treatments for samples of cases archived in cancer registries. (b) Indicators of rehabilitation success. These include: return to work, quality of life, and satisfaction of specific rehabilitation needs. Studies can be performed to estimate these indicators in individual countries, but to obtain comparable data across European countries it will be necessary to administer a questionnaire to randomly selected samples of patients from population-based cancer registry databases. However, three factors complicate questionnaire studies: patients may not be aware that they have cancer; incomplete participation in surveys could lead to bias; and national confidentiality laws in some cases prohibit cancer registries from approaching patients. Although these studies are expensive and difficult to perform, but as the number of cancer survivors increases, it is important to document their needs in order to provide information on cancer control
Casimir effect due to a single boundary as a manifestation of the Weyl problem
The Casimir self-energy of a boundary is ultraviolet-divergent. In many cases
the divergences can be eliminated by methods such as zeta-function
regularization or through physical arguments (ultraviolet transparency of the
boundary would provide a cutoff). Using the example of a massless scalar field
theory with a single Dirichlet boundary we explore the relationship between
such approaches, with the goal of better understanding the origin of the
divergences. We are guided by the insight due to Dowker and Kennedy (1978) and
Deutsch and Candelas (1979), that the divergences represent measurable effects
that can be interpreted with the aid of the theory of the asymptotic
distribution of eigenvalues of the Laplacian discussed by Weyl. In many cases
the Casimir self-energy is the sum of cutoff-dependent (Weyl) terms having
geometrical origin, and an "intrinsic" term that is independent of the cutoff.
The Weyl terms make a measurable contribution to the physical situation even
when regularization methods succeed in isolating the intrinsic part.
Regularization methods fail when the Weyl terms and intrinsic parts of the
Casimir effect cannot be clearly separated. Specifically, we demonstrate that
the Casimir self-energy of a smooth boundary in two dimensions is a sum of two
Weyl terms (exhibiting quadratic and logarithmic cutoff dependence), a
geometrical term that is independent of cutoff, and a non-geometrical intrinsic
term. As by-products we resolve the puzzle of the divergent Casimir force on a
ring and correct the sign of the coefficient of linear tension of the Dirichlet
line predicted in earlier treatments.Comment: 13 pages, 1 figure, minor changes to the text, extra references
added, version to be published in J. Phys.
Flare imaging with multibeam sonar systems: data processing for seep bubble detection
Multibeam sonar surveys have been conducted since their invention in the 1970s; however, mainly reflections from the seafloor were considered so far. More recently, water column imaging with multibeam is becoming of increasing interest for fisheries, buoy, mooring, or gas detection in the water column. Using ELAC SEABEAM 1000 data, we propose a technique to detect gas bubbles (flares) although this system is originally not designed to record water column data. The described data processing represents a case study
and can be easily adapted to other multibeam systems. Multibeam data sets from the Black Sea and the North Sea show reflections of gas bubbles that form flares in the water column. At least for reasonably intense gas escape the detection of bubbles is feasible. The multibeam technique yields exact determination of the source position and information about the dimension of the gas cloud in the water. Compared to conventional flare imaging by single-beam echo sounders, the wide swath angle of multibeam systems allows the mapping of large areas in much shorter time
Quark mixing from softly broken symmetries
Quark flavor mixing may originate in the soft breaking of horizontal
symmetries. Those symmetries, which in the simplest case are three family U(1)
groups, are obeyed only by the dimension-4 Yukawa couplings and lead, when
unbroken, to the absence of mixing. Their breaking may arise from the
dimension-3 mass terms of SU(2)-singlet vector-like quarks. Those gauge-singlet
mass terms break the horizontal symmetries at a scale much higher than the
Fermi scale, yet softly, leading to quark mixing while the quark masses remain
unsuppressed.Comment: 9 pages, plain Latex, no figure
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