Designing A United States History Curriculum: A Thematic Approach

A cun-iculum framework for a one-year eleventh grade United States History course was designed. The Framework included the development of nine themes at the unit level and one theme at the lesson level. Goals and objectives were developed at the course, unit, and lesson level. The potential for thematic instruction to improve history teaching was discussed, as well as the challenges of designing thematic curriculum

Strongly decreased gap junctional permeability to inositol 1,4,5-trisphosphate in connexin32 deficient hepatocytes

AbstractLivers from connexin32 (Cx32) deficient mice have been shown to be defective in hormonally induced glucose mobilization. In order to determine whether this effect is due to decreased diffusion of the second messenger inositol 1,4,5-trisphosphate (IP3) between hepatocytes, we injected iontophoretically different amounts of IP3 in Fura-2 loaded hepatocyte doublets (i.e. cell pairs) from wild type or Cx32 deficient mice. Whereas 84% of wild type hepatocytes showed an intercellular Ca2+ wave spreading from the injected cell to the neighboring cell, only 25% of Cx32 deficient hepatocyte doublets did so. The amount of IP3 necessary to induce an intercellular Ca2+ wave in Cx32 deficient hepatocyte doublets was estimated to be about 25-fold higher than in wild type doublets. This confirms the notion that the low hormonally or electrically induced glucose mobilization found in Cx32 deficient livers relative to wild type livers is due to largely hindered diffusion of IP3 between Cx32 deficient hepatocytes

Major Loss of the 28-kD Protein of Gap Junction in Proliferating Hepatocytes

There is a reduction in the 28-kD gap junction protein detectable by immunofluorescence in livers of partially hepatectomized rats and in cultured hepatocytes stimulated to proliferate. By the coordinate use of antibodies directed to the hepatic junction protein (HJP28) and the use of a monoclonal antibody that recognizes bromodeoxyuridine (BrdU) incorporated into DNA, we have been able to study the relationship between detectable gap junction protein and cell division. Hepatocytes that label with BrdU in the regenerating liver and in cell culture show a significant reduction of HJP28. Cells that do not synthesize DNA, on the other hand, show normal levels and distribution of immunoreactive gap junction protein. We postulate that the quantitative changes in gap junction expression might play an important role in the control of proliferation in the liver

Expression of connexin genes in the human retina

Background: Gap junction channels allow direct metabolically and electrical coupling between adjacent cells in various mammalian tissues. Each channel is composed of 12 protein subunits, termed connexins (Cx). In the mouse retina, Cx43 could be localized mostly between astroglial cells whereas expression of Cx36, Cx45 and Cx57 genes has been detected in different neuronal subtypes. In the human retina, however, the expression pattern of connexin genes is largely unknown. Methods: Northern blot hybridizations, RT-PCR as well as immunofluorescence analyses helped to explore at least partially the expression pattern of the following human connexin genes GJD2 (hCx36), GJC1 (hCx45), GJA9 (hCx59) and GJA10 (hCx62) in the human retina. Results: Here we report that Northern blot hybridization signals of the orthologuous hCx36 and hCx45 were found in human retinal RNA. Immunofluorescence signals for both connexins could be located in both inner and outer plexiform layer (IPL, OPL). Expression of a third connexin gene denoted as GJA10 (Cx62) was also detected after Northern blot hybridization in the human retina. Interestingly, its gene structure is similar to that of Gja10 (mCx57) being expressed in mouse horizontal cells. RT-PCR analysis suggested that an additional exon of about 25 kb further downstream, coding for 12 amino acid residues, is spliced to the nearly complete reading frame on exon2 of GJA10 (Cx62). Cx59 mRNA, however, with high sequence identity to zebrafish Cx55.5 was only weakly detectable by RT-PCR in cDNA of human retina. Conclusion: In contrast to the neuron-expressed connexin genes Gjd2 coding for mCx36, Gjc1 coding for mCx45 and Gja10 coding for mCx57 in the mouse, a subset of 4 connexin genes, including the unique GJA9 (Cx59) and GJA10 (Cx62), could be detected at least as transcript isoforms in the human retina. First immunofluorescence analyses revealed a staining pattern of hCx36 and hCx45 expression both in the IPL and OPL, partially reminiscent to that in the mouse, although additional post-mortem material is needed to further explore their sublamina-specific distribution. Appropriate antibodies against Cx59 and Cx62 protein will clarify expression of these proteins in future studies

Governo eletrônico na mídia on line: análise de repercussão das iniciativas de e-gov em publicações jornalísticas na web

Dissertação (mestrado) - Universidade Federal de Santa Catarina, Centro Tecnológico. Programa de Pós-Graduação em Engenharia de Produção.A presente pesquisa teve o objetivo geral de avaliar a repercussão nos meios de comunicação das ações governamentais relacionadas ao processo de implantação do governo eletrônico. Como objetivos específicos, buscou-se identificar as publicações com maior volume e freqüência sobre governo eletrônico, os assuntos e instâncias governamentais com maior destaque no noticiário e avaliar aspectos qualitativos da cobertura. Trata-se de um estudo descritivo, com a análise estatística sobre um conjunto de 475 notícias coletadas de diversas fontes jornalísticas on line entre junho de 2001 e novembro de 2002. Confirmando os pressupostos assumidos, o estudo demonstrou que: a veiculação de notícias sobre governo eletrônico é restrita, em razão de suas especificidades tecnológicas; as iniciativas de governo eletrônico do Poder Executivo federal são veiculadas com maior destaque; a cobertura tende a enfatizar aspectos relacionados à prestação de serviços, com menor destaque para questões relacionadas ao controle social do Estado. As conclusões do estudo indicam que o debate sobre o governo eletrônico ainda se restringe principalmente à esfera administrativa do Estado, enquanto que há carência de abordagem mais ampla do tema governo eletrônico nos órgãos da grande imprensa, a qual, por deter um público leitor mais numeroso, inclusive entre a parcela da sociedade onde se situam os formadores de opinião, poderia dar uma maior repercussão social ao tema

Einfluss von Umgänglichkeitsmaßnahmen auf das Verhalten von Saugkälbern unter besonderer Berücksichtigung von Alter, Rasse und Geschlecht der Tiere sowie Häufigkeit der Maßnahmen

Ziel der vorliegenden Arbeit war eine Einschätzung des Temperaments von Saugkälbern mit Hilfe von zwei Testverfahren, die die Bewegungsmöglichkeit der Kälber einschränken. Insbesondere wurde untersucht, ob bei mehrmals durchgeführten Tests bei Kälbern ein Gewöhnungseffekt auf das Verhalten der Kälber erkennbar wird, der sich bei späteren Maßnahmen positiv auswirkt. Weiterhin waren Temperamentunterschiede zwischen den verwendeten Rassen Dt. Angus und Dt. Fleckvieh sowie zwischen männlichen und weiblichen Kälbern Ziel der Untersuchung. Die Versuche wurden im Jahr 2002 mit 244 Nachkommen von 7 Dt. Angus- und 6 Dt. Fleckvieh-Bullen durchgeführt. Es wurden zwei Testverfahren eingesetzt, die zur Einschätzung des Temperaments geeignet sind: der Anbindetest und der Wiegetest. Nach der Geburt und beim Wiegetest wurde von allen Kälbern das Körpergewicht erfasst. Außerdem wurde bei allen Tests eine Blutprobe zur Ermittlung des Serumkortisolgehaltes entnommen. Mit Kälbern bis zur 5. Lebenswoche wurde bis zu drei Mal der Anbindetest durchgeführt. Der Wiegetest kam ab dem 3. Lebensmonat zur Anwendung und wurde nach dem Absetzen von den Muttertieren wiederholt. Beim Anbindetest wurde das Temperament der Kälber mit einem Score von null bis fünf beurteilt, außerdem wurde die Zeit, die sie sich in Bewegung befanden, erfasst. Während ein Kalb angebunden war, wurde ebenfalls das Verhalten dessen Muttertieres mit einem Score von null bis fünf benotet. Beim Wiegetest wurden die Art des Ein- und Austritts in bzw. aus der Waage mit einem Score von eins bis drei beurteilt, ebenso wie viel Zeit hierfür benötigt wurde. In der Waage wurde das Temperament mit einem Score von eins bis fünf beurteilt. Weiterhin wurde zu diesem Zeitpunkt der Hornstatus der Fleckviehkälber aufgenommen. Die Temperamentparameter wurden mit Hilfe von Varianzanalysen berechnet. Bei beiden Tests wurden außerdem Lautäußerungen, Kot- und Harnabsatz erfasst. Diese Parameter wurden rein deskriptiv ausgewertet. Die Ergebnisse zeigen, dass bei Kälbern bis zur 5. Lebenswoche ein Gewöhnungseffekt an Handlingmaßnahmen auftrat, der aber nicht über einen längeren Zeitraum anhielt. Außerdem stellte sich heraus, dass die Fixierung in einem Fangstand den Tieren mehr Stress bereitet als das Anbinden mit einem Kopfstrick. Dt. Fleckvieh-Kälber zeigten sich tendenziell schwieriger im Umgang als Dt. Angus-Kälber, was sich in etwas längerer Bewegungszeit beim Anbindetest, etwas schnelleren Fluchtgeschwindigkeiten beim Verlassen der Waage und höheren Kortisolwerten beim Wiegetest äußerte. Ebenso waren weibliche Kälber tendenziell unruhiger als männliche Tiere. Dies äußerte sich in geringfügig längerer Bewegungszeit beim Anbindetest und schnellerem Eintritt in die Waage. Auch hatten sie bei allen Tests tendenziell höhere Serumkortisolkonzentrationen. Zwischen den Nachkommen der einzelnen Bullen waren Unterschiede erkennbar, die auf eine genetische Veranlagung von Temperament hindeuten. Die Behornung der Fleckvieh-Kälber wirkte sich nicht auf das Temperament aus. Die Serumkortisolkonzentration zeigte sich nicht geeignet als Indikator für das Temperament. Kot- und Urinabsatz, sowie Lautäußerungen konnten nur teilweise als Untermauerung des Temperaments erkannt werden. Weiterhin konnte ein Zusammenhang zwischen der Gewichtsentwicklung der Kälber und deren Temperament dahingehend hergestellt werden, dass schwere Kälber niedrigere Temperamentscores erhielten. Abschließend lässt sich sagen, dass Gewöhnungseffekte durch einzelne Maßnahmen erzielt werden können. Um langfristig erleichterten Umgang v.a. mit älteren Tieren zu erreichen sind jedoch weitere Versuche notwendig, die z.B. Vergleichbarkeit der Testmethoden und Abstände zwischen den Tests berücksichtigen.It was the aim of the study to evaluate the temperament of suckling calves using two testing methodologies based on restraining calves movements. Of particular interest was the potential positive adaption of calves behaviour by sequential testing. The experiments were performed in 2002 with 244 progenies of seven Dt. Angus and six Dt. Fleckvieh bulls at Lehr- und Versuchsbetrieb Rudlos. Two different temperament tests (fixation and squeeze-chute) were used. After birth and during the squeeze-chute-test body weight of all calves was recorded. In addition blood samples were taken in each test to determine the concentration of serumcortisol. Calves were tested by fixation with a rope up to three times in their first five weeks of life. The Squeeze-Chute-Test was performed once when calves reached about three months and again after they were separated from their mothers. While fixed with a rope, calves temperament was scored from zero to five, further on time in movement was stopped. During fixation of the calves, their mothers temperament was also ranked from zero to five. During the Squeeze-Chute-Test the way calves walked in the chute and the way they left was scored from one to three. In addition the time they needed to walk in and out was stopped. In the chute, temperament was measured with a score from one to five. Within Dt.Fleckvieh it was noted, if the calves were horned or polled. The temperament parameters were evaluated by GLM-Procedure. During both tests the sound of the calves, defaecation and urination were recorded. These parameters were only evaluated in a descriptive way. The results show, that calves habituate to handling up to the age of five weeks, but this effect does not last for a longer period. Furthermore the results give evidence that fixing in a squeeze-chute stresses calves more than fixing them with a rope. Dt. Fleckvieh calves tended to be more excitable than Dt. Angus calves, as they moved longer while rope-tested, leaved the squeeze-chute quicker and showed higher cortisol concentrations in the squeeze-chute. Female calves tended to be more excitable than male calves, as they also moved longer during rope-testing moved quicker in the squeeze-chute and showed higher cortisol levels during all tests. There was no difference in Fleckvieh calves temperament if they were horned or polled. The progenies of the different bulls showed significant differences in temperament indicating a genetic influence in terms of temperament. The concentration of serumcortisol was not useful as an indicator for temperament in this study. Defaecation, urination and sound of the calves were only partially related with temperament. The growth rate of calves was related with their temperament scores docile animals with low temperament scores grow better than excitable cattle with high scores. Finally the results show, that habituation to handling is possible by performing it several times. To reach longlasting effects, especially with elder calves, some more measures are needed, for example the comparability of tests and frequency of testing

The electrical behaviour of rat connexin46 gap junction channels expressed in transfected HeLa cells

Pairs of human HeLa cells expressing rat connexin46 were used to study the electrical properties of gap junction channels with the dual voltage-clamp method. The steady-state conductance (g j,ss) had a bell-shaped dependence on transjunctional voltage (V j). The parameters of the Boltzmann fit were: V j,0=42mV, g j,min=0.12, z=2.5 (pipette solution: K+ aspartate−; 27°C). The Boltzmann parameters were sensitive to the ionic composition of the pipette solution (KCl, K+ aspartate−, TEA+ Cl−, TEA+ aspartate−). The Vj-dependent inactivation of the junctional current I j was approximated by single exponentials (exceptions: two exponentials with KCl at V j≥75mV and K+ aspartate− at V j=125mV). The time constant of inactivation (τi) decreased with increasing V j and was sensitive to the pipette solution. The larger the ions, the slower the inactivation. Recovery from inactivation followed a single exponential. The time constant of recovery (τr) increased with increasing V j. Single-channel currents showed a main state, several substates and a residual state. The corresponding conductances γj,main and γj,residual decreased slightly with increasing V j; extrapolation to V j=0mV yielded values of 152 and 28pS, respectively (K+ aspartate−; 37°C). The values of γj,main and γj,residual were dependent on pipette solution. The ratio γj,main/γj,residual increased with increasing ionic size, suggesting that the residual state impairs ion permeation more severely than the main state. The γj,main data suggest that the ionic selectivity of Cx46 channels may be controlled primarily by ionic size. Compared with hemichannel results, docking of connexons may modify the channel structure and thereby affect the ionic selectivity of gap junction channels. The open channel probability at steady state (P o) decreased with increasing V j. The parameters of the Boltzmann fit were: V j,0=41mV, z=2.2 (K+ aspartate−; 27°C