Solusi Numerik Model Sir Dengan Menggunakan Metode Runge-Kutta Orde Empat Dalam Prediksi Penyebaran Virus Covid-19 Di Provinsi Maluku

Penelitian ini bertujuan untuk memprediksi penyebaran virus Covid-19 di Provinsi Maluku menggunakan metode Runge-Kutta orde empat. Model matematika penyebaran virus Covid-19 berbentuk sistem persamaan diferensial yang mencakup variabel Susceptible (S) yaitu populasi manusia yang rentan terinveksi virus Covid-19, Infectious (I) yaitu populasi manusia yang telah terinveksi virus Covid-19 dan Recovered (R) yaitu populasi manusia yang sudah sembuh atau yang sudah kebal terhadap virus Covid-19, yang digunakan sebagai nilai awal. Nilai  sebagai nilai parameter yang diselesaikan secara numerik menggunakan metode Runge-Kutta orde empat yang dilakukan sebanyak 20 iterasi dengan waktu interval  bulan menggunakan data dari Dinas Kesehatan Provinsi Maluku dan Polda Maluku tahun 2020 sampai 2021. Berdasarkan data yang diperoleh maka nilai rata-rata dari data tersebut yang digunakan sebagai nilai awal dimana , , . Nilai awal dan nilai parameter disubstitusikan kedalam solusi numerik dan disimulasikan menggunakan dan Matlab sebagai alat bantu. Nilai laju setiap kelas untuk 20 bulan kedepan yaitu untuk laju kelas individu rentan (S) sebesar 69.270 jiwa, untuk laju kelas individu terinfeksi (I) sebesar 19.167 jiwa dan untuk laju kelas individu sembuh (R) sebesar 851 jiwa. Ini berarti bahwa untuk populasi (S) dan (I) akan mengalami penurunan untuk 20 bulan kedepan sedangkan untuk populasi (R) akan mengalami kenaikan pada 20 bulan kedepan

Geoprocessamento no contexto de empresas de pesquisa.

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Fluctuation and fixation of rodenticide resistance alleles in Rattus norvegicus

Berthier, K., Benoit, E., Berny, P., Lasseur, R., Merville, A., Peigneaux, F., Cosson, J.-F

Estimation des paramètres génétiques de la vitesse de croissance et du poids des agneaux avant le sevrage en race mérinos d'arles

International audienc

Índice climático de crescimento de pastagens naturais no Rio Grande do Sul

The climatic index of pasture growth, of Fitzpatrick & Nix, was tested and applied with good results to Rio Grande do Sul State, Brazil. An exponential regression equation Y = 353,1 (e1.40x) where x is the climatic index of growth of tropical grasses, can be used to estimate the dry matter yield of natural grasslands, using average air temperature, rainfall and shunshine. Tables were developed for the quick determination of the thermal index for each group of forages, and the light index, both indexes being necessary for the climatic index calculation. The normal, monthly climatic index, for ten locations within the State was determined as well as the frequency of its different values for a period of 30 years, at Uruguaiana and São Luiz Gonzaga. A low climatic potential for the productivity of natural grasslands is a definitive characteristic of Rio Grande do Sul State, in winter and in dry summers. Hay can be obtained from the native grassland itself, in summer, and used in winter as feed supplement. There is a good climatic potentiality along all the year for the temperate grasses and legumes, but no adequate climate for tropical legumes during the coldest months of the winter.O índice climático de crescimento de pastagens, de Fitzpatrick & Nix, foi testado e considerado satisfatório nas condições do Estado do Rio Grande do Sul. Uma equação de regressão do tipo exponencial, Y = 353,1 (e1,40X) onde x é o índice climático de crescimento de gramíneas tropicais, permite estimar o rendimento de matéria seca (kg/ha) da pastagem natural. Para uso desta equação é necessário conhecer temperatura média, precipitação pluvial e insolação. Foram organizadas tabelas que permitem rápida determinação do índice térmico para cada grupo de forrageiras - e do índice de luz, necessários para o cálculo do índice climático. Foi determinado o índice climático mensal normal para cada grupo de forrageiras, em dez locais do Rio Grande do Sul. Para as localidades de Uruguaiana e São Luiz Gonzaga, foi determinada a frequência dos valores dos índices climáticos, cm cada mês, durante 30 anos de observação. Verificou-se que o potencial de produtividade das pastagens naturais é insuficiente, quando o índice climático de crescimento é inferior a 0.1 o que ocorre no inverno, e em verões secos. Para pastagens nativas, a suplementação alimentar com feno, no inverno e verões secos, é grande importância, dada a grande variabilidade, de ano para ano, dos índices climáticos e das estações. Este feno pode ser obtido da própria pastagem nativa, durante o verão, pois, nesta estação, a produtividade das pastagens é superior à necessidade de um bovino adulto/ha. Há boa potencialidade climática, durante todos os meses do ano para gramíneas e leguminosas temperadas. Para as leguminosas tropicais, os meses mais rigorosos do inverno não possuem clima adequado

The effect of culture preservation techniques on patulin and citrinin production by Penicillium expansum Link

Aims: To study the influence of culture preservation methods and culture conditions on the production of the mycotoxins patulin and citrinin by Penicillium expansum. Methods and results: Ten strains of Penicillium expansum were preserved using subculture and maintenance at 4 ºC, mineral oil, drying on silica gel and freeze-drying. Patulin and citrinin production was assessed on yeast extract sucrose agar (YES) and grape juice agar (GJ), using TLC before and after 0.5, 2–3, 6 and 12 months preservation. Citrinin was detected in all cultures for all preservation techniques on YES. The patulin profiles obtained differed with strain and culture media used. Conclusions: Citrinin production seems to be a stable character for the tested strains. There is a tendency for patulin detection with time apparently more consistent for silica gel storage and freeze-drying, especially when the strains are grown on GJ. Significance and Impact of the Study: Variability in the profiles of the mycotoxins tested seems to be more strain-specific than dependent on the preservation technique used

Cerium-Based Spontaneous Coating Process for Corrosion Protection of Aluminum Alloys

A cerium-based coating for corrosion resistance is applied by exposing a cleaned aluminum-based component to a corrosion-inhibiting cerium solution containing cerium ions in the presence of an oxidizing agent. The coating deposits spontaneously without an external source of electrons

A chromosome-scale assembly reveals chromosomal aberrations and exchanges generating genetic diversity in Coffea arabica germplasm

In order to better understand the mechanisms generating genetic diversity in the recent allotetraploid species Coffea arabica, here we present a chromosome-level assembly obtained with long read technology. Two genomic compartments with different structural and functional properties are identified in the two homoeologous genomes. The resequencing data from a large set of accessions reveals low intraspecific diversity in the center of origin of the species. Across a limited number of genomic regions, diversity increases in some cultivated genotypes to levels similar to those observed within one of the progenitor species, Coffea canephora, presumably as a consequence of introgressions deriving from the so-called Timor hybrid. It also reveals that, in addition to few, early-occurring exchanges between homoeologous chromosomes, there are numerous recent chromosomal aberrations including aneuploidies, deletions, duplications and exchanges. These events are still polymorphic in the germplasm and could represent a fundamental source of genetic variation in such a lowly variable species