18 research outputs found
Code Flows: Visualizing Structural Evolution of Source Code
No full textUnderstanding detailed changes done to source code is of great importance in software maintenance. We present Code Flows, a method to visualize the evolution of source code geared to the understanding of fine and mid-level scale changes across several file versions. We enhance an existing visual metaphor to depict software structure changes with techniques that emphasize both following unchanged code as well as detecting and highlighting important events such as code drift, splits, merges, insertions and deletions. The method is illustrated with the analysis of a real-world C++ code system.
Telea: Teaching of the English language to Asian students
No full textIncludes bibliographical references (pages 63-67)The purpose of the project was to present a case for the development of a more effective, modified, multi -faceted approach to teach English to students from Taiwan, Hongkong, japan, and Korea, including the development of a set of components for curriculum design to be used in conjunction with this approach. Review of literature and approaches to teaching English ???as-a-second language and the general concepts and strategies of ESL and those being used for East Asian students were discussed. Comparisons were made of the language and cultural backgrounds of these East Asian students. The experiences of the author as a teacher to speakers of Spanish, Chinese, Japanese, Korean, and American English were reviewed. A field trip to the Far East by the author was undertaken to validate observations and experiments used in the development of a new technique to teach East Asian students. Through comparisons of linguistic differences between English and Chinese, the parent language of East Asian languages, the components of the instructional program, teaching of the English Language to East Asians, were developed, utilizing the receptive and productive skills: listening, reading, speaking, and writing. A more complete professional preparation program for teachers of East Asians was recommended. Experimental studies and related research directed toward improvement of instructional strategies in this area was also encouraged
Telea: Teaching of the English language to Asian students
No full textThe purpose of the project was to present a case for the development of a more effective, modified, multi -faceted approach to teach English to students from Taiwan, Hongkong, japan, and Korea, including the development of a set of components for curriculum design to be used in conjunction with this approach. Review of literature and approaches to teaching English –as-a-second language and the general concepts and strategies of ESL and those being used for East Asian students were discussed. Comparisons were made of the language and cultural backgrounds of these East Asian students. The experiences of the author as a teacher to speakers of Spanish, Chinese, Japanese, Korean, and American English were reviewed. A field trip to the Far East by the author was undertaken to validate observations and experiments used in the development of a new technique to teach East Asian students. Through comparisons of linguistic differences between English and Chinese, the parent language of East Asian languages, the components of the instructional program, teaching of the English Language to East Asians, were developed, utilizing the receptive and productive skills: listening, reading, speaking, and writing. A more complete professional preparation program for teachers of East Asians was recommended. Experimental studies and related research directed toward improvement of instructional strategies in this area was also encouraged.Includes bibliographical references (pages 63-67)California State University, Northridge. Department of Education
Evaluation of Russian sturgeon (Acipenser gueldenstaedtii) Semen Quality and Semen Cryopreservation
No full textSIMPLE SUMMARY: The decline in sturgeon populations, including Russian sturgeons, has reached alarming levels, threatening these species with extinction. The requirements for the meat of these fish, caviar and other products used in the textile, medical and food industries are constant or even on the rise. Reproductive biotechnologies seem to be the main solution to these problems, but the many unknowns related to the particularities of the species still place them far from the efficiency reached in some species of domestic animals. The development of fish farms for sturgeons and the intensification of reproductive biotechnologies is the main way in which the natural habitats affected by depopulation can be repopulated and to respond to the consumption and industrial requirements of the population. Our purpose is to contribute with additional novel information on the cryopreservation of sturgeon spermatozoa, as well as the evaluation of semen quality with the aim of developing a cryopreservation technique suitable for commercial breeding facilities. ABSTRACT: The alarming decline in sturgeon populations doubled by growing demands for sturgeon products, urge us to prevent the loss of these species. Fish stocking in natural habitats and developing fish farms are viable solutions, which can be successfully implemented with the help of reproductive biotechnologies. Despite the fact that semen cryopreservation is admittedly an important step for saving the Russian sturgeon, a reproducible standard method with good results has yet to be identified. Sperm quality assessment is essential for quantifying the impact of cryopreservation on spermatozoa. The purpose of our study was to provide additional information regarding semen cryopreservation and semen quality evaluation for the Russian sturgeon. Our study method is based on the use of two yolk-free extenders (with different cryoprotectants: DMSO and methanol) for freezing semen, using a simple freezing protocol. Parameters such as volume, concentration, motility, morphology and membrane integrity were evaluated. In conclusion, cryopreservation of Russian sturgeon spermatozoa using an extender containing methanol as cryoprotectant led to high egg fertilization percentages (72.67 ± 5.4%) even if the total motility values recorded for thawed semen were quite low (18–25%). Additionally, we identified two optimal stains for morphological studies and morphometry (Spermac stain kit and Trypan Blue Solution)
Diferenças interindividuais em teleatendimento de emergências: explicitação por meio da entrevista de autoconfrontação
No full textO objetivo deste artigo é duplo. No âmbito teórico, apresenta a noção de modos operatórios singulares e diferenciados desenvolvidos no setor de telea tendimento; no âmbito metodológico, busca apresentar o valor da entrevista de autoconfrontação no estudo da atividade de trabalho. Inicialmente, são apresentados os métodos e os procedimentos utilizados para analisar a atividade em um serviço de atendimento às situações de emergências urbanas e, em seguida, é descrito o funcionamento do contexto produtivo estudado. Os trechos de diálogos de dez casos observados em situação foram autoconfrontados, permitindo aos autores a apresentação do desenrolar particular de cada atendimento dirigido pelo operador. Finalmente, discute-se a influência das diferenças interindividuais na atividade de teleatendimento e nos possíveis danos à saúde dos operadores
EXPERIMENTAL TRIES TO ESTABLISH THE PREIMPLANTATIONAL MAMMALIAN EMBRYOS VIABILITY THROUGHOUT STAINING
No full textPresently there are more methods to assess embryo quality but, still the wieldy usedremains the morphological criteria method. In this experiment were tested twostaining methods for embryos and oocytes. The embryos were recovered from mousefemale at 72 hours after mating. The recovered embryos were first evaluated aftermorphological criteria and than by Trypan blue exclusion and Neutral red staining.Using Trypan blue exclusion were evaluated 30 embryos from which 19 (63.3) wereclassified as viable and 11 (36.7) were classified as nonviable. By Neutral redstaining were evaluated 37 embryos from which 24 (64.8) were considered viableand 13 (35.2) were considered nonviable. The oocytes recovered were alsoevaluated using the two methods: using Trypan blue exclusion were stained 10oocytes from which 9 remained uncolored and were considered viable and 1 wasstained in blue and was considered nonviable and using Neutral red 13 oocytes werestained from which 9 were evaluated as viable and 4 as nonviable
THE INFLUENCE OF K-CASEIN ALLELES ON MILK PRODUCTION AND QUALITY IN A HOLSTEIN-FRISIAN COW POPULATION
No full textMilk production and its composition are determined by quantitative loci, whichunder the influence of some environmental factors are producing an allelicvariability, meaning a genetic polymorphism of the gene. K-casein is a milk proteinwhose genetic polymorphism can serve as molecular marker for milk production,composition and industrial processing suitability. The allelic variants for k-casein Aand B are the most common and the most important of them. The experiments wereconducted on 24 Holstein-Friesian milking cows from a private farm in Giroc. Themilk production on a normal lactation is 8444 milk kg/305 days, with a fat percentof 3.9 and a protein percent of 3.3. The cows were divided in three groups AA, ABand BB in function of the genotyped obtained after the allelic variantsdetermination. The DNA isolation was made from hair roots and blood, the cowpopulation studied is not in genetic equilibrium fore k-casein gene, the frequency ofallele A is 0.43 and the frequency of B allele is 0.58. The highest genotype frequencywas 0.5 for CSN3-AB genotype, the BB genotype had 0.33 frequency, and the lowestfrequency was 0.17 for AA genotype. The mean daily milk production from cowswith BB genotype for k-casein is significant (p<5%) higher compared to the allelicvariant AA. The fat percent is significant higher at the allelic variant AA comparedto the other allelic variants (AB and BB) of the k-casein gene. Between the fatpercent of the three genotypes variants of K-casein (AA, AB and BB) there are nosignificant differences
STUDIES REGARDING THE CRIOPROTECTIVE PROPRIETIES OF THE VITRIFICATION MEDIA, WITH DMSO, SUCROSE, FICOLL 70 AND GALACTOSE USED IN EMBRYO CRYOPRESERVATION
No full textThe aim of our paper was to make a series of experiments in order to determine the
concentration at which four cryoprotectants (DMSO, sucrose, Ficoll 70 and
galactose) singly and in pairs would vitrify on plunging into liquid nitrogen and
remain vitreous when thawed in water bath. As penetrating cryoprotector we used
DMSO (MW=78.13 Da, Sigma D5879) and as nonpenetrating cryoprotectors we
used sucrose (MW=342.3 Da, Sigma S7903), Ficoll 70 (MW= 60,000-80,000 Da,
Sigma F4375) and Galactose (MW = 180,16 Da; Sigma G 6152). For DMSO there
were tested concentrations from 1M to 6.5M, with concentrations step of 0.5M. For
the nonpenetrating cryoprotectors there were tested concentrations of 5%, 10%,
15% and 20%. There were a total number of 168 solutions tested. The solutions
vitrification ability on freezing was tested by direct plunging into liquid nitrogen at -
196°C. Three thawing temperatures were tested 20°C, 25°C and 37°C. The
concentration at which DMSO solutions passed into vitreous state was 5M, but at
thawing none of them remained vitreous at thawing. When pairs of cryoprotectors
were tested 67 solutions vitrified at freezing (23 for DMSO-sucrose, 23 for DMSOFicoll 70 and 21 for DMSO-galactose) and 26 of them remained vitreous at
thawing. The DMSO and galacose pair give the best results on thawing (11 solution
remained vitreous on warming) at 37°C
EFFECT OF CZB CULTURE MEDIA ON IN VITRO DEVELOPMENT OF CLONED MOUSE EMBRYOS
No full textThe effect of simple and sequential embryo culture media on the preimplantationdevelopment of mouse nuclear transfer (NT) embryos reconstructed with cumuluscell nuclei using a mechanical NT technique was studied. Blastocyst formation ratewas evaluated using CZB medium. Nonmanipulated and sham-manipulatedparthenogenetic embryos served as controls for, respectively, the medium and thehandling technique. Rates of blastocyst formation for medium and handling controlembryos were similar in CZB (50% and 53%). Development of NT embryos wassignificantly impaired from the two-cell stage onwards, reaching the blastocyst stage ata rate of 4% in CZB. These data demonstrate not only that NT embryos are moresensitive to in vitro culture conditions than parthenogenetic control embryos but alsothat selection of culture media can influence the preimplantation development of NTembryos
STUDIES REGARDING THE VIABILITY OF MOUSE EMBRYOS RECOVERED IN EARLY DEVELOPMENTAL STAGES
No full textIn order to evaluate the embryo viability we tested 2 cultivation media in three
combinations (M16, Nutrient mixture F- 12 HAM supplemented with BSA and
Nutrient mixture F- 12 HAM without BSA). In the third day of cultivation the
embryos viability was assessed by morphological criteria and randomly by staining
with fluorescents dyes (Fluorescein diacetate and Propidium iodide). It was
observed that both media used for in vitro cultivation assured embryo development
up to the expanded blastocyst stage (21.33% for M 16 and 4.34% respectively),
exception the Nutrient mixture F- 12 HAM without BSA in which after 3 days
cultivation all embryos were degenerated. The M16 medium assured the embryos
development up to the hatched blastocyst stage (5.33%). None of the media
supported the development of embryos under 8 cell stages and early blockage in
stage of 2 cells could not be prevented
