Tetrazolium test for evaluating triticale seed viability

Freshly harvested triticale seeds are usually dormant, making the immediate evaluation of the physiological potential of seed lots difficult. We evaluated different triphenyl tetrazolium chloride (TTC) test methods for rapidly determining the viability of four seed lots of x.Triticosecale Wittmack cultivar IPR111. The test variables were: Preconditioning, (i) placing whole seeds between moistened paper towels or (ii) directly soaking the seeds in water, both procedures being conducted at 20 ºC for 18 hours; Post-conditioning seed preparation, (i) longitudinal bisection of the seed through the embryo with one half being stained and the other discarded or (ii) longitudinal bisection with both halves being stained; Staining for three and four hours, in the dark, with 0.1%, 0.5% or 1.0% (w/v) TTC according to the preconditioning method described above, (i) both halves of each seed were placed on filter paper moistened with TTC and maintained at 40 ºC or (ii) one half of each seed was immersed in 5 mL of TTC solution in a 100 mL glass beaker at 30 ºC. The best results were obtained by preconditioning seeds between moistened paper towels at 20 ºC for 18 hours and staining on filter paper with 1.0% (w/v) TTC for three hours at 40 ºC.

Viability of barley seeds by the tetrazolium test

The tetrazolium test is used to control seed quality of various plant species since it allows a rapid evaluation of viability. Freshly harvested barley seeds show dormancy that can make the germination test ineffective for an immediate evaluation. Therefore, the development of more efficient methods, such as the tetrazolium test, is necessary. The objective of this research work was to study various procedures for performing the tetrazolium test on barley seeds. Five lots of cv. BRS 195 barley seeds were used and subjected to the following treatments: two different methods of seed preconditioning (direct immersion in H2O and between sheets of moistened paper towels); two types of preparation for staining (longitudinal cross-section of the seed through the embryo with immersion of one half in a 2,3,5 triphenyl tetrazolium chloride solution or placing both halves on top of filter paper moistened with the tetrazolium salt solution); two methods of staining (on top of filter paper and direct immersion in the tetrazolium salt solution). Three concentrations of the tetrazolium salt solution (0.1%, 0.5%, and 1.0%) were used. It was concluded that the tetrazolium test on barley seeds may be accomplished with preconditioning by direct immersion in H2O and staining by immersing in a 0.1% or 0.5% concentration of tetrazolium salt solution or staining on top of filter paper moistened with such solution at a 1.0% concentration.

Test of exudates color hues for evaluating the physiological potential of coffee (Coffea arabica L.) seeds

Coffee seeds have slow and irregular germination, losing fast their viability during storage, and the standard germination test of these seeds requires at least 30 days. Besides, the results may not reflect the actual physiological quality of these seeds. The objective of this work was to develop a fast and practical test for evaluating the viability of coffee seeds, which is based on the interpretation of different color hues of exudates from seeds. Coffee seeds of the cultivar Catuai 44 from six lots were submitted to germination, accelerated aging, and electrical conductivity tests. In the exudates color hue test, coffee seeds without the parchment and the silvery pellicle (four replications of 10 seeds each) were distributed on top of paper towels moistened and then maintained into a germinator, at 25 ºC for 24, 48, 72, 96, and 120 h. Three classes of color hues were established: colorless, light color hue, and dark color hue, assigning the values of 0, 1, and 3, for each class, respectively. The proposed exudates color hue test can be recommended for the fast assessment of viability for coffee seeds. The most promising results were obtained for seeds with 12% moisture content, after imbibition periods of 72, 96, and 120 h; and with 30% moisture content, after imbibition periods of 72 and 120 h.

Effect of loading type on the fatigue strength of symmetric and asymmetric welded joints made of ultra high strength steel

In this study, finite element analyses and experimental tests are carried out in order to investigate the effect of loading type and symmetry on the fatigue strength of three different non-load carrying welded joints. The current codes and recommendations do not give explicit instructions how to consider degree of bending in loading and the effect of symmetry in the fatigue assessment of welded joints. The fatigue assessment is done by using effective notch stress method and linear elastic fracture mechanics. Transverse attachment and cover plate joints are analyzed by using 2D plane strain element models in FEMAP/NxNastran and Franc2D software and longitudinal gusset case is analyzed by using solid element models in Abaqus and Abaqus/XFEM software. By means of the evaluated effective notch stress range and stress intensity factor range, the nominal fatigue strength is assessed. Experimental tests consist of the fatigue tests of transverse attachment joints with total amount of 12 specimens. In the tests, the effect of both loading type and symmetry on the fatigue strength is studied. Finite element analyses showed that the fatigue strength of asymmetric joint is higher in tensile loading and the fatigue strength of symmetric joint is higher in bending loading in terms of nominal and hot spot stress methods. Linear elastic fracture mechanics indicated that bending reduces stress intensity factors when the crack size is relatively large since the normal stress decreases at the crack tip due to the stress gradient. Under tensile loading, experimental tests corresponded with finite element analyzes. Still, the fatigue tested joints subjected to bending showed the bending increased the fatigue strength of non-load carrying welded joints and the fatigue test results did not fully agree with the fatigue assessment. According to the results, it can be concluded that in tensile loading, the symmetry of joint distinctly affects on the fatigue strength. The fatigue life assessment of bending loaded joints is challenging since it depends on whether the crack initiation or propagation is predominant.

Automated UI testing. WBCT, a computer-automated user test environment tool.

Today, the user experience and usability in software application are becoming a major design issue due to the adaptation of many processes using new technologies. Therefore, the study of the user experience and usability might be included in every software development project and, thus, they should be tested to get traceable results. As a result of different testing methods to evaluate the concepts, a non-expert on the topic might have doubts on which option he/she should opt for and how to interpret the outcomes of the process. This work aims to create a process to ease the whole testing methodology based on the process created by Seffah et al. and a supporting software tool to follow the procedure of these testing methods for the user experience and usability.

Concept Test evaluación de potencial y aceptación para el nuevo

Banco del conocimiento

Pre test evaluación renovación matrícula mercantil

Banco del conocimiento

Herramienta Test Coequipero

Desarrollo empresarial y creación de empresa

Herramienta. Circunflejo test

Desarrollo empresarial y creación de empresa

Herramienta. Test competencias empresariales

Desarrollo empresarial y creación de empresa

Herramienta. Test de negociación

Desarrollo empresarial y creación de empresa

Herramientas Auto-Test diagnóstico cliente

Desarrollo empresarial y creación de empresa