Profile, Plan and Section: Three Developments for Sea-Bed Survey

The purpose of this article is to offer a response to some of the requirements, indicated in previous contributions, in underwater measurement and detection. The instruments described here were demonstrated to delegates during the International Hydrographic Conference in April 1967. Most of the accompanying records were taken during the course of the Conference

Understanding Teacher Leadership in Middle School Mathematics: A Collaborative Research Effort

We report findings from a collaborative research effort designed to examine how teachers act as leaders in their schools. We find that teachers educated by the Math in the Middle Institute act as key sources of advice for colleagues within their schools while drawing support from a network consisting of other teachers in the program and university-level advisors. In addition to reporting on our findings, we reflect on our research process, noting some of the practical challenges involved, as well as some of the benefits of collaboration

Structural health monitoring through dense instrumentation by community participants: the Community Seismic Network and Quake-Catcher Network

The Community Seismic Network and Quake-Catcher Network involve participants from communities at large to install low-cost accelerometers in houses and buildings for assessment of shaking intensity due to earthquakes. The seismometers are designed for two types of connec-tions: a USB-connected device which connects to the host’s computer, and a stand-alone sensor-plug-computer device that directly connects to the internet. The three-component sensors report both continuous data and amplitude anomalies in local acceleration to a Cloud computing service consisting of data centers geographically distributed across the continent, or to a distributed computing system. The continuous time series waveform data are being used to evaluate response parameters such as peak acceleration, peak velocity, and inter-story drift values. In addition, modal properties such as fundamental and higher mode frequencies and mode shapes are being computed from small and moderate earthquake data from the building. Building motion is computed for every floor of the building using only earthquake records from a single floor. Visualization models that map the instrumented buildings’ responses have been construct-ed using SketchUp and an associated plug-in to Matlab with recorded shaking data. This data visualization approach is different from other techniques because each building model is customized to show actual data recorded from that building on varying spatial scales, without the need for large-scale parallel computing facilities or complicated software that requires a steep learning curve

Infrastructure Redesign and Instructional Reform in Mathematics: Formal Structure and Teacher Leadership

Designing infrastructures to support instruction remains a challenge in educational reform. This article reports on a study of one school system\u27s efforts to redesign its infrastructure for mathematics instruction by promoting teacher leadership. Using social network and interview data from 12 elementary schools, we explore how the district\u27s infrastructure redesign efforts were internally coherent with and built upon existing infrastructure components. We then explore relations between infrastructure and school practice as captured in the instructional advice- and information-seeking interactions among school staff, finding that teacher leaders emerged as central actors and brokers of advice and information about mathematics within and between schools. Further, changes in school advice and information networks were associated with shifts in teachers\u27 beliefs about and practices in mathematics toward inquiry-oriented approaches consistent with district curriculum. We argue that the district\u27s redesign efforts to support teacher leadership coupled district curriculum and school and classroom practice in mathematics

First Complete Genome Sequence of a Genotype A2, Subgroup 4 Small Ruminant Lentivirus

Genetic variation in the ovine TMEM154 gene associates with susceptibility to small ruminant lentivirus (SRLV) infection. We report here the first complete genome sequence for a genotype A2, subgroup 4 SRLV isolated from a Hampshire ewe with two copies of a TMEM154 frameshift mutation predicted to abolish protein function

First Complete Genome Sequence of a Genotype A2, Subgroup 4 Small Ruminant Lentivirus

Genetic variation in the ovine TMEM154 gene associates with susceptibility to small ruminant lentivirus (SRLV) infection. We report here the first complete genome sequence for a genotype A2, subgroup 4 SRLV isolated from a Hampshire ewe with two copies of a TMEM154 frameshift mutation predicted to abolish protein function

Grasses and Legumes for Cellulosic Bioenergy

Human life has depended on renewable sources of bioenergy for many thousands of years, since the time humans fi rst learned to control fi re and utilize wood as the earliest source of bioenergy. The exploitation of forage crops constituted the next major technological breakthrough in renewable bioenergy, when our ancestors began to domesticate livestock about 6000 years ago. Horses, cattle, oxen, water buffalo, and camels have long been used as sources of mechanical and chemical energy. They perform tillage for crop production, provide leverage to collect and transport construction materials, supply transportation for trade and migratory routes, and create manure that is used to cook meals and heat homes. Forage crops—many of which form the basis of Grass: The 1948 Yearbook of Agriculture (Stefferud, 1948), as well as the other chapters of this volume—have composed the principal or only diet of these draft animals since the dawn of agriculture

Dating Clinopyroxene Phenocrysts in Submarine Basalts Using ^(40)Ar/^(39)Ar Geochronology

Dating submarine basalts using ^(40)Ar/^(39)Ar geochronology is often hindered by a lack of potassium‐bearing phenocrystic phases and severe alteration in the groundmass. Clinopyroxene is a common phenocrystic phase in seafloor basalts and is highly resistive to low‐temperature alteration. Here we show that clinopyroxene phenocrysts separated from marine basalts are a viable phase for ^(40)Ar/^(39)Ar incremental heating age determinations. We provide results from a pilot study comprising 16 age experiments from nine clinopyroxene separates, five of which from samples with dated coeval phases. The clinopyroxene ages range from 11.5 to 112 Ma with relatively high uncertainties (ranging from 0.8% to 7.1%; median of 1.9%) compared to more traditional phases. The clinopyroxene age plateaus form at low to moderate temperature steps and are characterized by relatively elevated K/Ca of 0.002–0.4, suggesting that other K‐bearing phases hosted within the clinopyroxene are likely degassing to yield the ^(40)Ar/^(39)Ar age information. There are three possible origins for the K and corresponding ^(40)Ar* including films of trapped melt/nanomineral inclusions along grain defects, secondary melt inclusion bands, or variations in degassing behaviors between lower and higher crystalline Ca pyroxene phases. Regardless of the source of the K, the age determinations are successful with 75% of the experiments producing long plateaus (>60% ^(39)Ar released) with mean square of the weighted deviations ranging from 0.6 to 1.5 and probability of fit values >0.05. We conclude that clinopyroxene dating by the ^(40)Ar/^(39)Ar method has the potential to provide a wealth of information for previously undated, altered seafloor lithologies and continental equivalents

IntCal20 tree rings: an archaeological Swot analysis

We undertook a strengths, weaknesses, opportunities, and threats (SWOT) analysis of Northern Hemisphere tree-ring datasets included in IntCal20 in order to evaluate their strategic fit with the demands of archaeological users. Case studies on wiggle-matching single tree rings from timbers in historic buildings and Bayesian modeling of series of results on archaeological samples from Neolithic long barrows in central-southern England exemplify the archaeological implications that arise when using IntCal20. The SWOT analysis provides an opportunity to think strategically about future radiocarbon (14C) calibration so as to maximize the utility of 14C dating in archaeology and safeguard its reputation in the discipline

Complete Genome Sequences of Two Genotype A2 Small Ruminant Lentiviruses Isolated from Infected U.S. Sheep

Two distinct subgroups of genotype A2 small ruminant lentiviruses (SRLVs) have been identified in the United States that infect sheep with specific host trans- membrane protein 154 (TMEM154) diplotypes. Here, we report the first two com- plete genome sequences of SRLV strains infecting U.S. sheep belonging to genotype A2, subgroups 1 and 2