Brokers, Binders, and Builders: Greater Miami\u27s Boom of the Mid-1920s

Six decades have passed since greater Miami and all the rest of Florida were immersed in an orgy of land speculation and a vast array of construction projects referred to as the boom. Miami and its environs were the storm center of the boom, which began to reach fever pitch in 1924. This speculative period crested in the latter part of 1925, when the price of land rose to unheard of heights, and construction commenced on a myriad of ambitious building projects. The boom ended in 1926

The Four-Day School Week: Impact on Student Academic Performance

Although the four-day school week originated in 1936, it was not widely implemented until 1973 when there was a need to conserve energy and reduce operating costs. This study investigated how achievement tests scores of schools with a four-day school week compared with schools with a traditional five-day school week. The study focused on student performance in Colorado where 62 school districts operated a four-day school week. The results of the Colorado Student Assessment Program (CSAP) were utilized to examine student performance in reading, writing, and mathematics in grades 3 through 10. While the mean test scores for five-day week schools exceeded those of four-day week schools in 11 of the 12 test comparisons, the differences were slight, with only one area revealing a statistically significant difference. This study concludes that decisions to change to the four-day week should be for reasons other than student academic performance

Linear Chains of Styrene and Methyl-Styrene Molecules and their Heterojunctions on Silicon: Theory and Experiment

We report on the synthesis, STM imaging and theoretical studies of the structure, electronic structure and transport properties of linear chains of styrene and methyl-styrene molecules and their heterojunctions on hydrogen-terminated dimerized silicon (001) surfaces. The theory presented here accounts for the essential features of the experimental STM data including the nature of the corrugation observed along the molecular chains and the pronounced changes in the contrast between the styrene and methyl-styrene parts of the molecular chains that are observed as the applied bias is varied. The observed evolution with applied bias of the STM profiles near the ends of the molecular chains is also explained. Calculations are also presented of electron transport along styrene linear chains adsorbed on the silicon surface at energies in the vicinity of the molecular HOMO and LUMO levels. For short styrene chains this lateral transport is found to be due primarily to direct electron transmission from molecule to molecule rather than through the silicon substrate, especially in the molecular LUMO band. Differences between the calculated position-dependences of the STM current around a junction of styrene and methyl-styrene molecular chains under positive and negative tip bias are related to the nature of lateral electron transmission along the molecular chains and to the formation in the LUMO band of an electronic state localized around the heterojunction.Comment: 17 pages plus 11 figures. To appear in Physical Review

Controls on Floc Size in a Continental Shelf Bottom Boundary Layer

Simultaneous in situ observations of floc size, waves, and currents in a continental shelf bottom boundary layer do not support generally accepted functional relationships between turbulence and floc size in the sea. In September and October 1996 and January 1997, two tripods were deployed in 70 m of water on the continental shelf south of Woods Hole, Massachusetts. On one a camera photographed particles in suspension 1.2 m above the bottom that had equivalent circular diameters larger than 250 um, and on the other, three horizontally displaced acoustic current meters measured flow velocity 0.35 m above the bottom. The tripods were separated by ~ 150 m. Typically, maximal floc diameter stayed relatively constant, around 1 mm, and it showed a dependence on turbulence parameters that was significantly weaker than that predicted by any model that assumes that turbulence-induced stresses limit floc size. Occasionally, when waves and currents generated intense near-bed turbulence, flocs were destroyed. These precipitous decreases in maximal floc size also were not predicted by conventional models. The correlation in time between episodes of floc destruction and elevated combined wave current stresses provides the first quantitative support for the hypothesis that floc size throughout bottom boundary layers can be controlled by breakup in the intensely sheared near-bed region. These observations demand a reassessment of the forces limiting floc size in the sea, and they indicate the potential for significant simplifying assumptions in models of floc dynamics

First record of the one-stripe anthias Pseudanthias fasciatus (Kamohara,1954) (Perciformes: Serranidae: Anthiinae) from Indian waters

The anthiinid fish Pseudanthias fasciatus (Kamohara, 1954) is reported from Indian waters for the first time. These fishes were found in trawler bycatch landed at the Neendakara fisheries harbour (090 41’ 18.28" N lat. 760 33’ 05.89" E long.) near Kollam, Kerala, India. The morphometric and meristic characters of the two specimens obtained correspond with those of P. fasciatus published previously

PDE8 controls CD4(+) T cell motility through the PDE8A-Raf-1 kinase signaling complex

The levels of cAMP are regulated by phosphodiesterase enzymes (PDEs), which are targets for the treatment of inflammatory disorders. We have previously shown that PDE8 regulates T cell motility. Here, for the first time, we report that PDE8A exerts part of its control of T cell function through the V-raf-1 murine leukemia viral oncogene homolog 1 (Raf-1) kinase signaling pathway. To examine T cell motility under physiologic conditions, we analyzed T cell interactions with endothelial cells and ligands in flow assays. The highly PDE8-selective enzymatic inhibitor PF-04957325 suppresses adhesion of in vivo myelin oligodendrocyte glycoprotein (MOG) activated inflammatory CD4(+) T effector (Teff) cells to brain endothelial cells under shear stress. Recently, PDE8A was shown to associate with Raf-1 creating a compartment of low cAMP levels around Raf-1 thereby protecting it from protein kinase A (PKA) mediated inhibitory phosphorylation. To test the function of this complex in Teff cells, we used a cell permeable peptide that selectively disrupts the PDE8A-Raf-1 interaction. The disruptor peptide inhibits the Teff-endothelial cell interaction more potently than the enzymatic inhibitor. Furthermore, the LFA-1/ICAM-1 interaction was identified as a target of disruptor peptide mediated reduction of adhesion, spreading and locomotion of Teff cells under flow. Mechanistically, we observed that disruption of the PDE8A-Raf-1 complex profoundly alters Raf-1 signaling in Teff cells. Collectively, our studies demonstrate that PDE8A inhibition by enzymatic inhibitors or PDE8A-Raf-1 kinase complex disruptors decreases Teff cell adhesion and migration under flow, and represents a novel approach to target T cells in inflammation

Teacher Preferences for Alternative School Site Administrative Models

Public school teachers with high leadership potential who stated that they had no interest in being school principals were surveyed on their attitudes about six alternative school site administrative organizational models. Of the 391 teachers surveyed, 53% identified the Co-Principal model as the preferred school site administrative structure. In order of preference were the Co-Principal model, the Principal/Business Manager model, the Multi-Principal model, the Principal/Associate Principal model, the Principal Teacher/Principal Administrator model, and the Principal/Educational Specialist model. Among teachers at the elementary, middle, and secondary levels, the only significant difference was on the Multi-Principal model, which was favored more by middle and high school teachers than by elementary teachers. The findings suggest that teachers who had previously reported a lack of interest in becoming school principals might be interested in the position if the organizational structure of the school site were different from the traditional organizational model