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In recent years, a concatenation of fears, pressures, and agendas has produced a new round of testing in the form of high school exit examinations. There has not, however, been an accompanying rush to see whether the exams do any good. No state has attempted to validate its test against external criteria: given the hyperbole surrounding the tests and the hundreds of millions of dollars spent to develop, administer, and score them, the political costs of finding that the tests are not working would be too great. The author explores the effects of high school exit exams and discusses the findings of a research conducted by Reardon, Atteberry, Arshan, and Kurlaender (2009) on the effects of exit exams on academic achievement. The research by Reardon et al. was consistent with another study by Warren, Grodsky, and Lee (2008). That research found that the class of 2006 faced an exit exam in 22 states: States have generally adopted HSEEs [high school exit examinations] in response to the perception that many high school graduates lack the skills required for success in the "new economy" and that requiring students to pass a high-stakes test that assesses their mastery of basic skills will make the high school diploma more meaningful to employers. Over the 20-year period they examined, Warren, Grodsky, and Lee found that the onset of an exit exams don't do what its advocates contended. They concluded that the results revealed no evidence that state HSEEs positively affect labor force status or earnings or that the connections between state HSEE policies and these outcomes vary by students' race/ethnicity or the level of difficulty of the state HSEEs... These examinations must be seen as a colossal waste of education and human resources, harmful to those whose educational attainments are curtailed by failing them and of little use to those who pass them (Warren et al., 2008, p. 101).

Presents conflicting legislation on calculator usage in California and Virginia, and summarizes research favoring students' use of calculators while taking tests and solving classroom exercises or real-world problems. Another research study shows that stayers in school choice programs are likely to have chosen the school, have friends in the program, and perform better than leavers. (MLH)

This study investigated phonological components of reading skill at two ages, using a novel pseudoword repetition task for assessing phonological memory (PM). Pseudowords were designed to incorporate control over segmental, prosodic and lexical features. In Experiment 1, the materials were administered to 3- and 4-year-old children together with a standardized test of phonological awareness (PA). PA and pseudoword repetition showed a moderate positive correlation, independent of age. Experiment 2, which targeted young adults, employed the same pseudoword materials, with a different administration protocol, together with standardized indices of PA, other memory measures and decoding skill. The results showed moderate to strong positive correlations among our novel pseudoword repetition task, measures of PM and PA and decoding. Together, the findings demonstrate the feasibility of assessing PM with the same carefully controlled materials at widely spaced points in age, adding to present resources for assessing PM and better enabling future studies to map the development of relationships among phonological capabilities in both typically developing children and those with language-related impairments. [ABSTRACT FROM AUTHOR]

We integrated high-resolution bare-earth airborne light detection and ranging (LiDAR) imagery with field observations and modern geochronology to characterize the Tahoe-Sierra frontal fault zone, which forms the neotectonic boundary between the Sierra Nevada and the Basin and Range Province west of Lake Tahoe. The LiDAR imagery clearly delineates active normal faults that have displaced late Pleistocene glacial moraines and Holocene alluvium along 30 km of linear, right-stepping range front of the Tahoe-Sierra frontal fault zone. Herein, we illustrate and describe the tectonic geomorphology of faulted lateral moraines. We have developed new, three-dimensional modeling techniques that utilize the high-resolution LiDAR data to determine tectonic displacements of moraine crests and alluvium. The statistically robust displacement models combined with new ages of the displaced Tioga (20.8 ± 1.4 ka) and Tahoe (69.2 ± 4.8 ka; 73.2 ± 8.7 ka) moraines are used to estimate the minimum vertical separation rate at 17 sites along the Tahoe-Sierra frontal fault zone. Near the northern end of the study area, the minimum vertical separation rate is 1.5 ± 0.4 mm/yr, which represents a two- to threefold increase in estimates of seismic moment for the Lake Tahoe basin. From this study, we conclude that potential earthquake moment magnitudes (Mw) range from 6.3 ± 0.25 to 6.9 ± 0.25. A close spatial association of landslides and active faults suggests that landslides have been seismically triggered. Our study underscores that the Tahoe-Sierra frontal fault zone poses substantial seismic and landslide hazards. [ABSTRACT FROM AUTHOR]

We present quantitative analyses of recent large rock falls in Yosemite Valley, California, using integrated high-resolution imaging techniques. Rock falls commonly occur from the glacially sculpted granitic walls of Yosemite Valley, modifying this iconic landscape but also posing signifi cant potential hazards and risks. Two large rock falls occurred from the cliff beneath Glacier Point in eastern Yosemite Valley on 7 and 8 October 2008, causing minor injuries and damaging structures in a developed area. We used a combination of gigapixel photography, airborne laser scanning (ALS) data, and ground-based terrestrial laser scanning (TLS) data to characterize the rock-fall detachment surface and adjacent cliff area, quantify the rock-fall volume, evaluate the geologic structure that contributed to failure, and assess the likely failure mode. We merged the ALS and TLS data to resolve the complex, vertical to overhanging topography of the Glacier Point area in three dimensions, and integrated these data with gigapixel photographs to fully image the cliff face in high resolution. Three-dimensional analysis of repeat TLS data reveals that the cumulative failure consisted of a near-planar rock slab with a maximum length of 69.0 m, a mean thickness of 2.1 m, a detachment surface area of 2750 m2, and a volume of 5663 ± 36 m3. Failure occurred along a surfaceparallel , vertically oriented sheeting joint in a clear example of granitic exfoliation. Stress concentration at crack tips likely propagated fractures through the partially attached slab, leading to failure. Our results demonstrate the utility of high-resolution imaging techniques for quantifying far-range (>1 km) rock falls occurring from the largely inaccessible, vertical rock faces of Yosemite Valley, and for providing highly accurate and precise data needed for rock-fall hazard assessment. [ABSTRACT FROM AUTHOR]

Collapse (suddenly falling down) was a dance/theater/ media production that brought together a diverse group of artists and scientists to explore the varied ways that social and natural systems collapse and the responses of human societies. This paper focuses on the nature of the collaboration, the unique products it produced and the lessons learned. Three art-science collaboration themes emerged: (1) implementation of a large-scale stereo display for 3D data; (2) exploration from a visual design perspective of digital scans of natural hazard sites normally used for scientific research; and (3) integration of optical tracking for interaction between performers and visualizations. Each theme is explored in detail and each member of the team reflects on lessons learned from the process. [ABSTRACT FROM AUTHOR]

We use data from two seismic networks and satellite interferometric synthetic aperture radar (InSAR) imagery to characterize the 22 December 2003 Mw 6.5 San Simeon earthquake sequence. Absolute locations for the mainshock and nearly 10,000 aftershocks were determined using a new three-dimensional (3D) seismic velocity model; relative locations were obtained using double difference. The mainshock location found using the 3D velocity model is 35.704° N, 121.096°Wat a depth of 9:7 ± 0:7 km. The aftershocks concentrate at the northwest and southeast parts of the aftershock zone, between the mapped traces of the Oceanic and Nacimiento fault zones. The northwest end of the mainshock rupture, as defined by the aftershocks, projects from the mainshock hypocenter to the surface a few kilometers west of the mapped trace of the Oceanic fault, near the Santa Lucia Range front and the >5 mm postseismic InSAR imagery contour. The Oceanic fault in this area, as mapped by Hall (1991), is therefore probably a second-order synthetic thrust or reverse fault that splays upward from the main seismogenic fault at depth. The southeast end of the rupture projects closer to the mapped Oceanic fault trace, suggesting much of the slip was along this fault, or at a minimum is accommodating much of the post-seismic deformation. InSAR imagery shows ~72 mm of postseismic uplift in the vicinity of maximum coseismic slip in the central section of the rupture, and ~48 and ~45 mm at the northwest and southeast end of the aftershock zone, respectively. From these observations, we model a ~30-km-long northwest-trending northeast-dipping mainshock rupture surface--called the mainthrust--which is likely the Oceanic fault at depth, a ~10-km-long southwest-dipping backthrust parallel to the mainthrust near the hypocenter, several smaller southwest-dipping structures in the southeast, and perhaps additional northeast-dipping or subvertical structures southeast of the mainshock plane. Discontinuous backthrust features opposite the mainthrust in the southeast part of the aftershock zone may offset the relic Nacimiento fault zone at depth. The InSAR data image surface deformation associated with both aseismic slip and aftershock production on the mainthrust and the backthrusts at the northwest and southeast ends of the aftershock zone. The well-defined mainthrust at the latitude of the epicenter and antithetic backthrust illuminated by the aftershock zone indicate uplift of the Santa Lucia Range as a popup block; aftershocks in the southeast part of the zone also indicate a popup block, but it is less well defined. The absence of backthrust features in the central part of the zone suggests range-front uplift by fault-propagation folding, or backthrusts in the central part were not activated during the mainshock. [ABSTRACT FROM AUTHOR]

We investigated involvement of feral swine in contamination of agricultural fields and surface waterways with Escherichia coli O157:H7 after a nationwide outbreak traced to bagged spinach from California. Isolates from feral swine, cattle, surface water, sediment, and soil at 1 ranch were matched to the outbreak strain. [ABSTRACT FROM AUTHOR]

Surface fracturing occurred along the San Andreas fault, the subparallel Southwest Fracture Zone, and six secondary faults in association with the 28 September 2004 (M 6.0) Parkfield earthquake. Fractures formed discontinuous breaks along a 32-km-long stretch of the San Andreas fault. Sense of slip was right lateral; only locally was there a minor (1-11 mm) vertical component of slip. Right-lateral slip in the first few weeks alter the event, early in its afterslip period, ranged from 1 to 44 mm. Our observations in the weeks following the earthquake indicated that the highest slip values are in the Middle Mountain area, northwest of the mainshock epicenter (creepmeter measurements indicate a similar distribution of slip). Surface slip along the San Andreas fault developed soon after the mainshock; field checks in the area near Parkfield and about 5 km to the southeast indicated that surface slip developed more than 1 hr but generally less than 1 day after the event. Slip along the Southwest Fracture Zone developed coseismically and extended about 8 km. Sense of slip was fight lateral; locally there was a minor to moderate (1-29 mm) vertical component of slip. Right-lateral slip ranged from 1 to 41 mm. Surface slip along secondary faults was right lateral; the fight-lateral component of slip ranged from 3 to 5 mm. Surface slip in the 1966 and 2004 events occurred along both the San Andreas fault and the Southwest Fracture Zone. In 1966 the length of ground breakage along the San Andreas fault extended 5 km longer than that mapped in 2004. In contrast, the length of ground breakage along the Southwest Fracture Zone was the same in both events, yet the surface fractures were more continuous in 2004. Surface slip on secondary faults in 2004 indicated previously unmapped structural connections between the San Andreas fault and the Southwest Fracture Zone, further revealing aspects of the structural setting and fault interactions in the Parkfield area. [ABSTRACT FROM AUTHOR]

Focuses on a study that augmented the global positioning system (GPS) data with interferometric synthetic aperture radar imagery to take into account the deformation associated with groundwater pumping and strike-slip faulting in Los Angeles, California. Overview of the data on the anthropogenic deformation in the area; Information on the GPS sites on the Santa Ana basin which is located in the area; Velocities measured in the GPS sites.

Studies the band of seismicity located between two earthquakes that occurred at Kern County and Walker Pass in California. Interpretation of the seismic lineament as a strike-slip fault; Relocation and calculation of focal mechanisms of the earthquakes.

Examines the doctrine of strict liability for abnormally dangerous activity in San Diego, California. Factors that lead to the near extinction of the strict liability; Examination of decisions applying sections 519 and 520 of the Restatement (Second) of Torts; Doctrinal barriers to strict liability.

Sherman Island, the westernmost island in the Sacramento–San Joaquin Delta in California, plays a crucial role in maintaining the water flux between saline ocean water from the San Francisco Bay to its west and the rest of the Delta to its east. Land elevation below mean sea level and continuous subsidence over the past century has made this island a high priority area for investigations of subsidence and restoration in the Delta. This study reports the results of successful application of Interferometric Synthetic Aperture Radar (InSAR) data and technique to measure subsidence in the Delta, which is a coherence-challenged non-urban area. We carried out a time-series interferometric analysis of Uninhabited Aerial Vehicle Synthetic Aperture Radar (UAVSAR) L-band (23.8 cm) data, collected from July 2009–August 2014, to assess both the spatial and temporal variation of subsidence on Sherman Island. We report both large-scale (island-wide) subsidence trends and small-scale (levee/farm scale) subsidence features in Sherman Island. Assuming the subsidence is linear during the five years of UAVSAR data acquisition, subsidence rates across the island range from 0–5 cm/yr, with an average of 1.3 ± 0.2 cm/yr. We estimate our systematic uncertainty to be 0.3 cm/yr. Overall, the central region in the island has subsided at a faster rate than the rest of the island. We find our results to be consistent with previous measurements of subsidence rates at electric transmission line towers scattered throughout the island. The results of this study provide insights into several factors influencing subsidence, including soil type, water table depth, land use, land elevation and the location and time of levee repairs. Subsidence monitoring on Sherman Island is essential for maintaining a reliable water supply for the state of California and for protecting the Delta ecosystem. [ABSTRACT FROM AUTHOR]