197 research outputs found
Selection in sugarcane based on inbreeding depression
This study aimed to evaluate the gene action associated with yield-related traits, including mean stalk weight (MSW), tons of sugarcane per hectare (TCH), and fiber content (FIB) in sugarcane. Moreover, the viability of individual reciprocal recurrent selection (RRSI-S1) was verified, and the effect of inbreeding depression on progenies was checked. The results were also used to select promising genotypes in S1 progenies. Eight clones (RB925345, RB867515,
RB739359, SP80-1816, RB928064, RB865230, RB855536, and RB943365) and their respective progenies, derived from selfing (S1), were evaluated. Several traits, including the number of stalks, MSW, soluble solids content determined in the field, stalk height, stalk diameter, TCH, soluble solids content determined in the laboratory, sucrose content, and FIB were evaluated in a randomized block design with hierarchical classification. The results showed that the traits with
predominant gene action associated with the dominance variance of MSW and TCH were most affected by inbreeding depression. The FIB, with predominant additive control, was not affected by selfing of the clones, and the RB867515⊗, RB928064⊗, RB739359⊗ and RB925345⊗ progenies performed best. Therefore, the use of S1 progenies for RRSI-S1 in sugarcane breeding programs is promising, and it should be explored for the future breeding of clones with high FIB levels
Genetic diversity and coefficient of parentage between clones and sugarcane varieties in Brazil
The success of the development of new sugarcane varieties is associated with the ability to correctly select the genitor. The aim of this study was to evaluate the genetic diversity between 113 clones and sugarcane varieties using the Ward-modified location model procedure with added information about the coefficient of parentage and endogamy. In this study, data was used from 100 experiments that evaluated clones; the experimental phase was conducted in 70 places between the years 2002 and 2009 on the outlining in random blocks. According to the diversity analysis, 3 groups formed: G1, G2, and G3, which were composed of 58, 8, and 47 genotypes, respectively. The clones of groups G1 and G3 were the most outstanding. Thus, biparental crossbreeding involving clones and varieties of these 2 groups can efficiently obtain transgressive genotypes. Knowledge of the heterotypic groups indicated by the Ward-modified location model method, along with the parentage information, will make it a lot easier to define the desirable and undesirable crossbreeds for public and private breeding programs that develop sugarcane varieties
Constructive and destructive use of compilers in elliptic curve cryptography
Although cryptographic software implementation is often performed by expert programmers, the range of performance and security driven options, as well as more mundane software engineering issues, still make it a challenge. The use of domain specific language and compiler techniques to assist in description and optimisation of cryptographic software is an interesting research challenge. In this paper we investigate two aspects of such techniques, focusing on Elliptic Curve Cryptography (ECC) in particular. Our constructive results show that a suitable language allows description of ECC based software in a manner close to the original mathematics; the corresponding compiler allows automatic production of an executable whose performance is competitive with that of a hand-optimised implementation. In contrast, we study the worrying potential for naïve compiler driven optimisation to render cryptographic software insecure. Both aspects of our work are set within the context of CACE, an ongoing EU funded project on this general topic
Drug biophysical profiling using lipid-based colloidal nanosystems and human serum albumin as biomimetic interfaces
The development of new drugs is a highly complex and expensive process, so it is crucial that less promising compounds are rejected early in the discovery phase before progressing to more expensive phases. This scenario impels researchers to refine and speed up the drug discovery process and to seek tools to support decisions related to modifications of the drug chemical structure to improve drugs’ properties and thus increase the probability of success in the process of drug discovery. [1], [2] In the drug discovery process it should be considered that in physiological environment there will be reciprocal interactions between drugs and biological interfaces, such as cell membranes or plasma proteins, and from those interactions different pharmacokinetic profiles can be achieved. [3] Thus, it is important to develop in vitro high throughput methods to evaluate the pharmaceutical profile, consisting in measuring properties such as permeability, lipophilicity, plasma protein binding, and biophysical changes of the membranes, which in turn affect other properties, such as the bioavailability of a drug and its pharmacokinetic profile. [4] Herein, the characterization of a newly synthesized drug (MIT-3) will be based on the measurement of fundamental biophysical properties, which allow inferring about its ADMET profile (absorption, distribution, excretion and toxicity at the membrane level). For this purpose, lipid-based colloidal nanosystems of different compositions were prepared as membrane mimetic models and several biophysical techniques were applied: derivative spectroscopy; quenching of steady-state and time-resolved fluorescence; quenching of intrinsic fluorescence of human serum albumin; synchronous fluorescence; dynamic and electrophoretic light scattering, differential scanning calorimetry and small and wide angle x-ray diffraction. The application of these techniques allowed to predict that MIT-3 has an ubiquitous location at the membrane level, presenting good membrane permeability and a good distribution in the therapeutic target. However, it is also predicted bioaccumulation with distribution in non-therapeutic targets and under conditions of prolonged exposure the drug may cause membrane toxicity as concluded by the impairment of membrane biophysical properties. It is also possible to conclude that the biophysical techniques and the biomimetic models used, constitute a toolbox of strategies for the future evaluation of other drugs.This work was supported by the Portuguese Foundation for Science and Technology (FCT) in the
framework of the Strategic Funding UID/FIS/04650/2013. We also acknowledge PEstC/QUI/UI0081/2013,
NORTE-01-0145-FEDER-000028 and PTDC/DTP-FTO/2433/2014. F. Cagide
and S. Benfeito are thankful for the pos-doctoral and doctoral grants (SFRH/BPD/74491/2010 and
SFRH/BD/99189/2013 respectively). Marlene Lúcio acknowledges the exploratory project funded by
FCT with the reference IF/00498/2012. Eduarda Fernandes acknowledges COMPETE 2020
“Programa Operacional Competitividade e internacionalização”.info:eu-repo/semantics/publishedVersio
The Tsallis statistical distribution applied to geomagnetically induced currents
Geomagnetically induced currents (GICs) have been long recognized as a ground effect arising from a chain of space weather events. GICs have been measured and modeled in many countries, resulting in a considerable amount of data. Previous statistical analyses have proposed various types of distribution functions to fit long-term GICs data sets. However, these extensive statistical approaches have been only partially successful in fitting the data sets. Here we use modeled GICs data sets calculated in four countries (Brazil, South Africa, United Kingdom, and Finland) using data from solar cycle 23 to show a plausible function based on a nonextensive statistical model of the q-exponential Tsallis function. The fitted q-exponential parameter is approximately the same for all locations, and the Lilliefors test shows good agreement with the q-exponential fits. From this fit, we compute that the likely numbers of extreme GICs events over the next ten solar cycles are 1–2 for both Finland and United Kingdom, at least one for Brazil and less than one event for South Africa. Our results indicate that the nonextensive statistics are a general characteristic of GICs, suggesting that the ground current intensity has a strong temporal correlation and long-range interaction
Biometric analysis of protein and oil contents of soybean genotypes in different environments
Aplicação de análises multivariadas para determinação da casta de abelhas Apis mellifera L. (Africanizadas), obtidas em laboratório
Tamanho de amostra para a estimação da média de caracteres de pêssego na colheita e após o armazenamento refrigerado
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