Examining The Quality Of The Evidence In Preservice Teacher Portfolios

2003 ◽  
Vol 54 (1) ◽  
pp. 57-73 ◽  
Author(s):  
Ginette Delandshere ◽  
Sheila A. Arens
Author(s):  
Siti Zumrotul Maulida ◽  
Ifah Silfianah ◽  
Ainun Nikmati Laily

<em>The disruption era is a challenge for the education sector because education is one of the areas that can support the quality of Indonesian human resources according to Kemenristekdikti priorities. This article aims to explore the development of personality competencies of preservice teachers in facing the challenges of disruption era. The function of teachers in the disruption era is different from that of teachers in the previous era, which is shifting to the function of cultivating ethical values, character, wisdom, experience, and social empathy because the function is impossible to do by machine. Thus, the challenge of educational institutions is to form the competence of preservice teacher personality which will build suitable exemplary based on expectation of teacher's role revolution in disruption era. There are four things that can be done in developing the personality competence of preservice teachers, some of them are: 1). religious matriculation programs, 2). application of student code of conduct, 3) Real Work Experience (KKN) program, and 4). integration of religious values in lectures.</em>


1988 ◽  
Vol 9 (3) ◽  
pp. 27-33 ◽  
Author(s):  
M. Winston Egan ◽  
Iva Dene Mccleary ◽  
Joan P. Sebastian ◽  
Helen Lacy

The impact of a two-way interactive television course for rural remote teacher preparation was evaluated using a variety of measures. Areas of primary importance reported in this paper are: ▪ How did learner outcomes of rural remote students compare to on-campus students participating in the same class? ▪ What were the perceptions of rural remote students regarding instructional quality of two-way interactive television? ▪ What were the perceptions of rural remote students regarding technology? Learner outcomes for on-campus and rural remote students were equivalent. Ratings regarding the quality of instruction and technology were above average except for provision of feedback to distance learners.


Author(s):  
K. T. Tokuyasu

During the past investigations of immunoferritin localization of intracellular antigens in ultrathin frozen sections, we found that the degree of negative staining required to delineate u1trastructural details was often too dense for the recognition of ferritin particles. The quality of positive staining of ultrathin frozen sections, on the other hand, has generally been far inferior to that attainable in conventional plastic embedded sections, particularly in the definition of membranes. As we discussed before, a main cause of this difficulty seemed to be the vulnerability of frozen sections to the damaging effects of air-water surface tension at the time of drying of the sections.Indeed, we found that the quality of positive staining is greatly improved when positively stained frozen sections are protected against the effects of surface tension by embedding them in thin layers of mechanically stable materials at the time of drying (unpublished).


Author(s):  
L. D. Jackel

Most production electron beam lithography systems can pattern minimum features a few tenths of a micron across. Linewidth in these systems is usually limited by the quality of the exposing beam and by electron scattering in the resist and substrate. By using a smaller spot along with exposure techniques that minimize scattering and its effects, laboratory e-beam lithography systems can now make features hundredths of a micron wide on standard substrate material. This talk will outline sane of these high- resolution e-beam lithography techniques.We first consider parameters of the exposure process that limit resolution in organic resists. For concreteness suppose that we have a “positive” resist in which exposing electrons break bonds in the resist molecules thus increasing the exposed resist's solubility in a developer. Ihe attainable resolution is obviously limited by the overall width of the exposing beam, but the spatial distribution of the beam intensity, the beam “profile” , also contributes to the resolution. Depending on the local electron dose, more or less resist bonds are broken resulting in slower or faster dissolution in the developer.


Author(s):  
G. Lehmpfuhl

Introduction In electron microscopic investigations of crystalline specimens the direct observation of the electron diffraction pattern gives additional information about the specimen. The quality of this information depends on the quality of the crystals or the crystal area contributing to the diffraction pattern. By selected area diffraction in a conventional electron microscope, specimen areas as small as 1 µ in diameter can be investigated. It is well known that crystal areas of that size which must be thin enough (in the order of 1000 Å) for electron microscopic investigations are normally somewhat distorted by bending, or they are not homogeneous. Furthermore, the crystal surface is not well defined over such a large area. These are facts which cause reduction of information in the diffraction pattern. The intensity of a diffraction spot, for example, depends on the crystal thickness. If the thickness is not uniform over the investigated area, one observes an averaged intensity, so that the intensity distribution in the diffraction pattern cannot be used for an analysis unless additional information is available.


Author(s):  
K. Shibatomi ◽  
T. Yamanoto ◽  
H. Koike

In the observation of a thick specimen by means of a transmission electron microscope, the intensity of electrons passing through the objective lens aperture is greatly reduced. So that the image is almost invisible. In addition to this fact, it have been reported that a chromatic aberration causes the deterioration of the image contrast rather than that of the resolution. The scanning electron microscope is, however, capable of electrically amplifying the signal of the decreasing intensity, and also free from a chromatic aberration so that the deterioration of the image contrast due to the aberration can be prevented. The electrical improvement of the image quality can be carried out by using the fascionating features of the SEM, that is, the amplification of a weak in-put signal forming the image and the descriminating action of the heigh level signal of the background. This paper reports some of the experimental results about the thickness dependence of the observability and quality of the image in the case of the transmission SEM.


Author(s):  
John H. Luft

With information processing devices such as radio telescopes, microscopes or hi-fi systems, the quality of the output often is limited by distortion or noise introduced at the input stage of the device. This analogy can be extended usefully to specimen preparation for the electron microscope; fixation, which initiates the processing sequence, is the single most important step and, unfortunately, is the least well understood. Although there is an abundance of fixation mixtures recommended in the light microscopy literature, osmium tetroxide and glutaraldehyde are favored for electron microscopy. These fixatives react vigorously with proteins at the molecular level. There is clear evidence for the cross-linking of proteins both by osmium tetroxide and glutaraldehyde and cross-linking may be a necessary if not sufficient condition to define fixatives as a class.


Author(s):  
Russell L. Steere ◽  
Eric F. Erbe ◽  
J. Michael Moseley

We have designed and built an electronic device which compares the resistance of a defined area of vacuum evaporated material with a variable resistor. When the two resistances are matched, the device automatically disconnects the primary side of the substrate transformer and stops further evaporation.This approach to controlled evaporation in conjunction with the modified guns and evaporation source permits reliably reproducible multiple Pt shadow films from a single Pt wrapped carbon point source. The reproducibility from consecutive C point sources is also reliable. Furthermore, the device we have developed permits us to select a predetermined resistance so that low contrast high-resolution shadows, heavy high contrast shadows, or any grade in between can be selected at will. The reproducibility and quality of results are demonstrated in Figures 1-4 which represent evaporations at various settings of the variable resistor.


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