Genetic diversity in soybean germplasm identified by SSR and EST-SSR markers.

Os objetivos deste trabalho foram avaliar a diversidade genética de 79 acessos de soja de diferentes regiões do mundo, agrupá-los de acordo com a similaridade e testar a correlação entre os dois tipos de marcadores utilizados. Foram utilizados marcadores microssatélites genômicos (SSR) e funcionais (EST-SSR). Trinta pares de primers SSR foram selecionados (20 genômicos e 10 EST-SSR) de acordo com sua distribuição nos 20 grupos de ligação da soja, com sua unidade de repetição trinucleotídica e com seu conteúdo de informação polimórfica. Todos os lócus analisados foram polimórficos, e 259 alelos foram encontrados. O número de alelos por lócus variou entre 2?21, com média de 8,63. Os acessos possuem uma quantidade significativa de alelos raros, sendo os acessos 19, 35, 63 e 65 os que apresentaram maior número de alelos exclusivos. Os acessos 75 e 79 são os mais similares e os acessos 31 e 35, e 40 e 78 são os mais divergentes. Foi observada baixa correlação entre resultados de SSR e EST-SSR. Portanto, uma análise adequada de diversidade em soja deve ser feita utilizando-se tanto marcadores microssatélites genômicos como funcionais. A diversidade genética dos acessos selecionados é alta, tendo sido encontrados cinco grupos e vários subgrupos. Observou-se moderada relação entre divergência genética e origem geográfica dos acessos

Physical Characteristics of Coffee Beans From Steaming Processin Single Column Reactor

One of important steps in decaffeination process is steaming. The aim of steaming is to expand coffee beans porosity in order to obtain optimal condition for decaffeination process. Steaming can be done in single column reactor using saturated water vapour as media. The objective of this research is to study physical characteristics of coffee beans after steaming process using single column reactor. Material tested was Robusta coffee with 13—14% moisture content after dry processing. Reactor capacity is 6 kg dried coffee beans and 30 l water to produce water vapour. Dried coffee beans classified in 4 grades, i.e. diameter size (d) d>7,5 mm; 6,5<d³7,5 mm; 5,5<d£6,5 mm; and d£5,5 mm. Period of steaming process varied from 1 up to 3.5 hours. The result showed that the coffee beans expanded 8.6—9.5% in length, 12.2—13.3% in width, and 18.3—20.6% in thickness. Coffee bean volume increased 30—50%. Coffee bean moisture content increased f. Aritmatic diameter increased 8—13% while geometric diameter increased 9—18%. Sphericity not affected. Surface area increased 18—37%. True density increased 19—30% while bulk density was while. Porosity increased from 13—18% to 24—39% while coffee beans texture decreased from 323—384 g/1 mm to 212—225 g/1 mm. Color change increased from 14—20 to 38—40. The optimum steaming process was 3 hours

Exponential absorption edge and disorder in Column IV amorphous semiconductors

We discuss the likely origin of the exponential absorption tail, or Urbach edge, of fourfold coordinated amorphous (a-)semiconductors. The present analysis is based on a compilation of a considerable amount of experimental data originating from a great variety of sample, alloys, and authors and obtained with quite different spectroscopic techniques. An attempt is made to correlate the measured Urbach edge with the structural and optical properties of the samples, The present analysis indicates that the Urbach edge may not only reflect the shape of the joint density of states of the valence and conduction band tails, but may also have important contributions from short-range order potential fluctuations produced by charged defects or impurities. (C) 1998 American Institute of Physics. [S0021-8979(98)02921-1].8495184519

The Influence Of The Available Scattering-vector Range On The Retrieval Of Particle-size Distributions From Small-angle Scattering Intensity Data

The determination of the particle-size distribution [D(r)J from small-angle scattering intensity data is discussed. The influence of the maximum available scattering vector hmax on D(r) retrieval is investigated with the help of numerical experiments with previously known solutions. The numerical corrector method provides a good answer even in cases where hmax is much smaller than those values necessary with other retrieval methods. © 1997 International Union of Crystallography all rights reserved.305 PART 2808810Fedorova, I.S., Schmidt, P.W., (1978) J. Appl. Cryst., 11, pp. 405-411Glatter, O., (1977) J. Appl. Cryst., 10, pp. 415-421Glatter, O., (1980) J. Appl Cryst., 13, pp. 7-11Glatter, O., Kratky, O., (1982) Small Angle X-ray Scattering, , New York: Academic PressGuinier, A., Fournet, A., (1955) Small Angle Scattering of X-rays, , New York: John WileyMulato, M., Chambouleyron, I., (1996) J. Appl. Cryst., 29, pp. 29-3

Optical diffraction gratings produced by laser interference structuring of amorphous germanium-nitrogen alloys

We use the interference of two pulsed laser beams (wavelength=355 nm) to produce an optical diffraction grating in amorphous germanium-nitrogen alloy (a-GeN). At the constructive maxima of the interference pattern, the absorption of light leads to crystallization. The crystallized region results of pure microcrystalline germanium (muc-Ge). An indication that Ge-N bonds have broken and nitrogen outdiffused of the film is obtained from infrared spectroscopy and confirmed by Raman spectra. A pattern of alternating a-GeN and muc-Ge lines with a period of about 4 mum acts as an optical diffraction grating due to the difference in optical properties between the two materials, and the three dimensional surface profile, caused by N-2 effusion, that is formed on the sample. (C) 2002 American Institute of Physics.81152731273

Laser crystallization and structuring of amorphous germanium

The short-pulse laser crystallization and interference structuring of amorphous germanium films were investigated by time resolved reflection measurements and Raman spectroscopy, We demonstrate that submicrometer crystalline structures with very sharp lateral interfaces can be produced by laser interference crystallization of nonhydrogenated samples. In hydrogenated films, on the other hand, the film surface disrupts upon laser exposure leading to the formation of a free-standing crystalline membrane, The Raman spectra of laser crystallized germanium display effects of finite crystallite size and stress. (C) 1997 American Institute of Physics.70263570357

Perubahan distribusi ukuran partikel tepung iles-iles hasil pengolahan dengan metode penggilingan bertingkat = (The Distribution Particle Sizes Change of Konjac Flour by Milling Method)

ABSTRACT The objectives of this research were to observe the distribution particle sizes change of konjac flour by dry milling method. The milling process of konjac flour included the milling by rotary cutter, burr mill, and conical ball mill. The particle size and the size distribution were determined by sieving, microscopic, and scanning electron microscope methods. The data obtained by using the microscopic method indicated the smallest geometric mean particles size, while data from the sieve method indicated the largest geometric mean size. The pictures obtained by using scanning electron microscope method showed the particles has broken after milling process by conical ball mill. The results indicated that the series of milling process decreased the geometric mean diameter, the finenes modulus, and the uniformity index of konjac flour particles. Key words. : milling, particle, Amorphophallu

Characteristics of nodule bacteria from Mimosa spp grown in soils of the Brazilian semiarid region.

The Brazilian Northeastern dry forest (Caatinga) is one of the diversification centers of Mimosa species. We determined the characteristics of native rhizobia isolates from nodules of Mimosa tenuiflora and Mimosa paraibana grown in pots with soils collected under Caatinga vegetation and compared the restriction ribosomal DNA profiles of the isolates with those of 16 reference strains. All plants formed abundant indeterminate nodules and all nodule isolates formed fast growing colonies. No colony altered the medium to an alkaline reaction and most of them produced low or medium amounts of extracellular polysaccharides. White and creamy colonies predominated among the isolates but orange and green colonies were present. Differences among the isolates from the Mimosa species tested are indicated by the greater phenotypic diversity of those obtained from M. tenuiflora. The analysis of the 16S rDNA gene suggests that the isolates from M. tenuiflora and M. paraibana are closely related and closer to B-rhizobia than to α-rhizobia. However, the similarity with all the tested B-rhizobia reference strains was relatively low suggesting that the isolates may belong to different bacteria species

SnO2 extended gate field-effect transistor as pH sensor

Extended gate field-effect transistor (EGFET) is a device composed of a conventional ion-sensitive electrode and a MOSFET device, which can be applied to the measurement of ion content in a solution. This structure has a lot of advantages as compared to the Ion- Sensitive Field Effect Transistor (ISFET). In this work, we constructed an EGFET by connecting the sensing structure fabricated with SnO2 to a commercial MOSFET (CD4007UB). From the numerical simulation of site binding model it is possible to determine some of the desirable characteristics of the films. We investigate and compare SnO2 films prepared using both the Sol-gel and the Pechini methods. The aim is an amorphous material for the EGFET. The SnO2 powder was obtained at different calcinating temperatures (200 - 500ºC) and they were investigated by X-ray diffraction (XRD), infrared spectroscopy (IR), thermogravimetric analysis (TGA) and differential thermal analysis (DTA). The films were investigated as pH sensors (range 2-11).47848