bluuebunny/crossref_metadata_2025 huggingface dataset:
Spatial regression analysis on 32 years total column ozone data
Authors: Knibbe J. S. , van der A R. J. , de Laat A. T. J.
Published: February 2014

Abstract. Multiple-regressions analysis have been performed on 32 years of total ozone column data that was spatially gridded with a 1° × 1.5° resolution. The total ozone data consists of the MSR (Multi Sensor Reanalysis; 1979–2008) and two years of assimilated SCIAMACHY ozone data (2009–2010). The two-dimensionality in this data-set allows us to perform the regressions locally and investigate spatial patterns of regression coefficients and their explanatory power. Seasonal dependencies of ozone on regressors are included in the analysis. A new physically oriented model is developed to parameterize stratospheric ozone. Ozone variations on non-seasonal timescales are parameterized by explanatory variables describing the solar cycle, stratospheric aerosols, the quasi-biennial oscillation (QBO), El Nino (ENSO) and stratospheric alternative halogens (EESC). For several explanatory variables, seasonally adjusted versions of these explanatory variables are constructed to account for the difference in their effect on ozone throughout the year. To account for seasonal variation in ozone, explanatory variables describing the polar vortex, geopotential height, potential vorticity and average day length are included. Results of this regression model are compared to that of similar analysis based on a more commonly applied statistically oriented model. The physically oriented model provides spatial patterns in the regression results for each explanatory variable. The EESC has a significant depleting effect on ozone at high and mid-latitudes, the solar cycle affects ozone positively mostly at the Southern Hemisphere, stratospheric aerosols affect ozone negatively at high Northern latitudes, the effect of QBO is positive and negative at the tropics and mid to high-latitudes respectively and ENSO affects ozone negatively between 30° N and 30° S, particularly at the Pacific. The contribution of explanatory variables describing seasonal ozone variation is generally large at mid to high latitudes. We observe ozone contributing effects for potential vorticity and day length, negative effect on ozone for geopotential height and variable ozone effects due to the polar vortex at regions to the north and south of the polar vortices. Recovery of ozone is identified globally. However, recovery rates and uncertainties strongly depend on choices that can be made in defining the explanatory variables. In particular the recovery rates over Antarctica might not be statistically significant. Furthermore, the results show that there is no spatial homogeneous pattern which regression model and explanatory variables provide the best fit to the data and the most accurate estimates of the recovery rates. Overall these results suggest that care has to be taken in determining ozone recovery rates, in particular for the Antarctic ozone hole.
Dynamics of particulate organic carbon flux in a global ocean model
Authors: Lima I. D. , Lam P. J. , Doney S. C.
Published: February 2014

Abstract. The sinking of particulate organic carbon (POC) is a key component of the ocean carbon cycle and plays an important role in the global climate system. However, the processes controlling the fraction of primary production that is exported from the euphotic zone (export ratio) and how much of it survives respiration in the mesopelagic to be sequestered in the deep ocean (transfer efficiency) are not well understood. In this study, we use a three-dimensional, coupled physical–biogeochemical model (CCSM–BEC; Community Climate System Model–ocean Biogeochemical Elemental Cycle) to investigate the processes controlling the export of particulate organic matter from the euphotic zone and its flux to depth. We also compare model results with sediment trap data and other parameterizations of POC flux to depth to evaluate model skill and gain further insight into the causes of error and uncertainty in POC flux estimates. In the model, export ratios are mainly a function of diatom relative abundance and temperature while absolute fluxes and transfer efficiency are driven by mineral ballast composition of sinking material. The temperature dependence of the POC remineralization length scale is modulated by denitrification under low O2 concentrations and lithogenic (dust) fluxes. Lithogenic material is an important control of transfer efficiency in the model, but its effect is restricted to regions of strong atmospheric dust deposition. In the remaining regions, CaCO3 content of exported material is the main factor affecting transfer efficiency. The fact that mineral ballast composition is inextricably linked to plankton community structure results in correlations between export ratios and ballast minerals fluxes (opal and CaCO3), and transfer efficiency and diatom relative abundance that do not necessarily reflect ballast or direct ecosystem effects, respectively. This suggests that it might be difficult to differentiate between ecosystem and ballast effects in observations. The model's skill in reproducing sediment trap observations is equal to or better than that of other parameterizations. However, the sparseness and relatively large uncertainties of sediment trap data makes it difficult to accurately evaluate the skill of the model and other parameterizations. More POC flux observations, over a wider range of ecological regimes, are necessary to thoroughly evaluate and test model results and better understand the processes controlling POC flux to depth in the ocean.
Seasonal shifts in the contributions of the Changjiang River and the Kuroshio Current to nitrate dynamics in the continental shelf of the northern East China Sea based on a nitrate dual isotopic composition approach
Authors: Umezawa Y. , Yamaguchi A. , Ishizaka J. , Hasegawa T. , Yoshimizu C. , Tayasu I. , Yoshimura H. , Morii Y. , Aoshima T. , Yamawaki N.
Published: February 2014

Abstract. The northern East China Sea (ECS) serves as a spawning and nursery ground for many species of fish and squid. To clarify the basis of the food web in the northern ECS, we examined the nitrate (NO3) dynamics along four latitudinal transects based on stable nitrogen and oxygen isotopes of NO3 (δ15NNO3 and δ18ONO3) and temperature–salinity dynamics in both winter (February 2009) and summer (July 2009 and July 2011). The δ15NNO3 and δ18ONO3, which were distinctly different among the potential NO3 sources, were useful for clarifying NO3 sources and its actual usage by phytoplankton. In winter, Kuroshio Subsurface Water (KSSW) and the Yellow Sea Mixed Water (YSMW) predominantly contributed to NO3 distributed in the shelf water. In the surface water of the Okinawa Trough, NO3 from the KSSW, along with a temperature increase caused by an intrusion of Kuroshio Surface Water (KSW), seemed to stimulate phytoplankton growth. In summer, Changjiang Diluted Water (CDW), Yellow Sea Cold Water Mass (YSCWM), and KSSW affected the distribution and abundance of NO3 in the northern ECS, depending on precipitation in the Changjiang drainage basin and the development of the YSCWM in the shelf bottom water. Although isotopic fractionation during NO3 uptake by phytoplankton seemed to drastically increase δ15NNO3 and δ18ONO3 in summer, relatively light nitrate with δ15NNO3 lower than expected from this fractionation effect might be explained by contribution of atmospheric nitrogen and/or nitrification to NO3 dynamics in the surface and subsurface layers. If the latter were a dominant process, this would imply a tightly coupled nitrogen cycle in the shelf water of the northern ECS.
Comparative organic geochemistry of Indian margin (Arabian Sea) sediments: estuary to continental slope
Authors: Cowie G. , Mowbray S. , Kurian S. , Sarkar A. , White C. , Anderson A. , Vergnaud B. , Johnstone G. , Brear S. , Woulds C. , Naqvi S. W. , Kitazato H.
Published: February 2014

Abstract. Surface sediments from sites across the Indian margin of the Arabian Sea were analysed for their carbon and nitrogen compositions (elemental and stable isotopic), grain size distributions and biochemical indices of organic matter (OM) source and/or degradation state. Site locations ranged from the estuaries of the Mandovi and Zuari rivers to depths of ~ 2000 m on the continental slope, thus spanning nearshore muds and sands on the shelf and both the semi-permanent oxygen minimum zone (OMZ) on the upper slope (~ 200–1300 m) and the seasonal hypoxic zone that impinges on the shelf. Source indices showed mixed marine and terrigenous OM within the estuaries, and overwhelming predominance (80%+) of marine OM on the shelf and slope. Thus, riverine OM is heavily diluted by autochthonous marine OM and/or is efficiently remineralised within or immediately offshore of the estuaries. Any terrigenous OM that is exported appears to be retained in nearshore muds; lignin phenols indicate that the small terrigenous OM content of slope sediments is of different origin, potentially from rivers to the north. Organic C contents of surface shelf and slope sediments varied from < 0.5 wt % in relict shelf sands to over 7 wt % at slope sites within the OMZ, decreasing to ≤ 1 wt % at 2000 m. Major variability (~ 5 wt %) was found at slope sites within the OMZ of similar depth and near-identical bottom-water oxygen concentration. A strong relationship between organic C and sediment grain size was seen for sediments within the OMZ, but lower C loadings were found for sites on the shelf and below the OMZ. Diagenetic indices confirmed that lower C content below the OMZ is associated with greater extent of OM degradation, but that C-poor shelf sediments are not consistently more degraded than those within the OMZ. Together, the results indicate that OM enrichment on the upper slope can be explained by physical controls (winnowing and/or dilution) on the shelf and progressive OM degradation with increasing oxygen exposure below the OMZ. Reduced oxygen exposure may contribute to OM enrichment at some sites within the OMZ, but hydrodynamic processes are the overriding control on sediment OM distribution.
A spatial investigation of the environmental controls over cryoconite aggregation on Longyearbreen glacier, Svalbard
Authors: Langford H. J. , Irvine-Fynn T. D. L. , Edwards A. , Banwart S. A. , Hodson A. J.
Published: February 2014

Abstract. A cryoconite granule is a near-spherical aggregation of biota and abiotic particles found upon glacier surfaces. Recently, microstructural studies have revealed that photosynthetic microorganisms and extracellular polymeric substances (EPS) are omnipresent within cryoconite granules and have suggested their importance as biological "forming factors". To assess these forming factors, and their biological control over aggregate size and stability, across a typical Arctic valley glacier surface, a suite of rapid, spectrophotometric, microplate methods were utilised. Subsequent spatial mapping of these data revealed distinct patterns. Labile carbohydrates were found to increase up-glacier, suggestive of EPS production for cryoprotection and nutrient assimilation. Conversely, pigment concentrations were found to increase down-glacier, with the exception of a zone of hydraulic erosion, suggestive of a general reduction in physical disturbance and of the build-up of photosynthetic pigments and less labile cyanobacterial sheath material. Aggregate size was found to increase towards the glacier edges, linked to the input of particulate matter from the valley sides, and to broadly increase down-glacier, in the same way as pigment concentrations. Statistical analyses of transect data revealed that the photoautotrophic count and carbohydrate–chlorophyll ratio of the cryoconite sampled could explain 83% of the measured variation in aggregate size and stability. Considering solely aggregate size, the number and length of photoautrophic filaments could explain 92% of the variation in this parameter. These findings demonstrate the two-dimensional distribution of key biological controls upon cryoconite aggregation for the first time, and highlight the importance of filamentous cyanobacteria and EPS production to the development of stable cryoconite granules.
Persistent millennial-scale link between Greenland climate and northern Pacific Oxygen Minimum Zone under interglacial conditions
Authors: Cartapanis O. , Tachikawa K. , Romero O. E. , Bard E.
Published: February 2014

Abstract. The intensity and/or extent of the northeastern Pacific Oxygen Minimum Zone (OMZ) varied in-phase with the Northern Hemisphere high latitude climate on millennial timescales during the last glacial period, indicating the occurrence of atmospheric and oceanic connections under glacial conditions. While millennial variability was reported for both the Greenland and the northern Atlantic Ocean during the last interglacial period, the climatic connections with the northeastern Pacific OMZ has not yet been observed under warm interglacial conditions. Here we present a new geochemical dataset, spanning the past 120 ka, for major components (terrigenous fraction, marine organic matter, biogenic opal, and carbonates) generated by X-ray fluorescence scanning alongside with biological productivity and redox sensitive trace element content (Mo, Ni, Cd) of sediment core MD02-2508 at 23° N, retrieved from the northern limit of the modern OMZ. Based on elemental ratios Si / Ti (proxy for opal), Cd / Al and Ni / Al, we suggest that biological productivity was high during the last interglacial (MIS5). Highly resolved opal reconstruction presents millennial variability corresponding to all the Dansgaard-Oeschger interstadial events over the last interglacial, while the Mo / Al ratio indicates reduced oxygenation during these events. Extremely high opal content during warm interstadials suggests high diatom productivity. Despite the different climatic and oceanic background between glacial and interglacial periods, rapid variability in the northeastern Pacific OMZ seems to be tightly related to Northern Hemisphere high latitude climate via atmospheric and possibly oceanic processes.
Modeling the effect of glacier recession on streamflow response using a coupled glacio-hydrological model
Authors: Naz B. S. , Frans C. D. , Clarke G. K. C. , Burns P. , Lettenmaier D. P.
Published: February 2014

Abstract. We describe an integrated spatially distributed hydrologic and glacier dynamic model, and use it to investigate the effect of glacier recession on streamflow variations for the upper Bow River basin, a tributary of the South Saskatchewan River, Alberta, Canada. Several recent studies have suggested that observed decreases in summer flows in the South Saskatchewan River are partly due to the retreat of glaciers in the river's headwaters. Modeling the effect of glacier changes on streamflow response in river basins such as the South Saskatchewan is complicated due to the inability of most existing physically based distributed hydrologic models to represent glacier dynamics. We compare predicted variations in glacier extent, snow water equivalent (SWE), and streamflow discharge with satellite estimates of glacier area and terminus position, observed glacier mass balance, observed streamflow and snow water-equivalent measurements, respectively over the period of 1980–2007. Observations of multiple hydroclimatic variables compare well with those simulated with the coupled hydrology-glacier model. Our results suggest that, on average, the glacier melt contribution to the Bow River flow upstream of Lake Louise is approximately 22% in summer. For warm and dry years, however, the glacier melt contribution can be as large as 47% in August, whereas for cold years, it can be as small as 15% and the timing of the glacier melt signature can be delayed by a month. The development of this modeling approach sets the stage for future predictions of the influence of warming climate on streamflow in partially glacierized watersheds.
Winter stream temperature in the rain-on-snow zone of the Pacific Northwest: influences of hillslope runoff and transient snow cover
Authors: Leach J. A. , Moore R. D.
Published: February 2014

Abstract. Stream temperature dynamics during winter are less well studied than summer thermal regimes, but the winter season thermal regime can be critical for fish growth and development in coastal catchments. The winter thermal regimes of Pacific Northwest headwater streams, which provide vital winter habitat for salmonids and their food sources, may be particularly sensitive to changes in climate because they can remain ice-free throughout the year and are often located in rain-on-snow zones. This study examined winter stream temperature patterns and controls in small headwater catchments within the rain-on-snow zone at the Malcolm Knapp Research Forest, near Vancouver, British Columbia, Canada. Two hypotheses were addressed by this study: (1) winter stream temperatures are primarily controlled by advective fluxes associated with runoff processes and (2) stream temperatures should be depressed during rain-on-snow events, compared to rain-on-bare-ground events, due to the cooling effect of rain passing through the snowpack prior to infiltrating the soil or being delivered to the stream as saturation-excess overland flow. A reach-scale energy budget analysis of two winter seasons revealed that the advective energy input associated with hillslope runoff overwhelms vertical energy exchanges (net radiation, sensible and latent heat fluxes, bed heat conduction, and stream friction) and hyporheic energy fluxes during rain and rain-on-snow events. Historical stream temperature data and modelled snowpack dynamics were used to explore the influence of transient snow cover on stream temperature over 13 winters. When snow was not present, daily stream temperature during winter rain events tended to increase with increasing air temperature. However, when snow was present, stream temperature was capped at about 5 °C, regardless of air temperature. The stream energy budget modelling and historical analysis support both of our hypotheses. A key implication is that climatic warming may generate higher winter stream temperatures in the rain-on-snow zone due to both increased rain temperature and reduced cooling effect of snow cover.
One-dimensional modelling of upper ocean mixing by turbulence due to wave orbital motion
Authors: Ghantous M. , Babanin A. V.
Published: February 2014

Abstract. Mixing of the upper ocean affects the sea surface temperature by bringing deeper, colder water to the surface. Because even small changes in the surface temperature can have a large impact on weather and climate, accurately determining the rate of mixing is of central importance for forecasting. Although there are several mixing mechanisms, one that has until recently been overlooked is the effect of turbulence generated by non-breaking, wind-generated surface waves. Lately there has been a lot of interest in introducing this mechanism into ocean mixing models, and real gains have been made in terms of increased fidelity to observational data. However, our knowledge of the mechanism is still incomplete. We indicate areas where we believe the existing parameterisations need refinement and propose an alternative one. We use two of the parameterisations to demonstrate the effect on the mixed layer of wave-induced turbulence by applying them to a one-dimensional mixing model and a stable temperature profile. Our modelling experiment suggests a strong effect on sea surface temperature due to non-breaking wave-induced turbulent mixing.
Ion acceleration by parallel propagating nonlinear Alfvén wave packets in a radially expanding plasma
Authors: Nariyuki Y. , Umeda T. , Suzuki T. K. , Hada T.
Published: February 2014

Abstract. The numerical simulation of the nonlinear evolution of the parallel propagating Alfvén waves in a radially expanding plasma is performed by using a kinetic-fluid model (the Vlasov–MHD model). In our study, both the nonlinear evolution of the Alfvén waves and the radial evolution of the velocity distribution function (VDF) are treated simultaneously. On the other hand, important ion kinetic effects such as ion cyclotron damping and instabilities driven by the non-equilibrium ion velocity distributions are not included in the present model. The results indicate that the steepened Alfvén wave packets outwardly accelerate ions, which can be observed as the beam components in the interplanetary space. The energy of imposed Alfvén waves is converted into the longitudinal fluctuations by the nonlinear steepening and the nonlinear Landau damping. The wave shoaling due to the inhomogeneity of the phase velocity is also observed.
Cyclone impact on sea ice in the central Arctic Ocean: a statistical study
Authors: Kriegsmann A. , Brümmer B.
Published: February 2014

Abstract. This study investigates the impact of cyclones on the Arctic Ocean sea ice for the first time in a statistical manner. We apply the coupled ice–ocean model NAOSIM which is forced by the ECMWF analyses for the period 2006–2008. Cyclone position and radius detected in the ECMWF data are used to extract fields of wind, ice drift, and concentration from the ice–ocean model. Composite fields around the cyclone centre are calculated for different cyclone intensities, the four seasons, and different sub-regions of the Arctic Ocean. In total about 3500 cyclone events are analyzed. In general, cyclones reduce the ice concentration in the order of a few percent increasing towards the cyclone centre. This is confirmed by independent AMSR-E satellite data. The reduction increases with cyclone intensity and is most pronounced in summer and on the Siberian side of the Arctic Ocean. For the Arctic ice cover the cumulative impact of cyclones has climatologic consequences. In winter, the cyclone-induced openings refreeze so that the ice mass is increased. In summer, the openings remain open and the ice melt is accelerated via the positive albedo feedback. Strong summer storms on the Siberian side of the Arctic Ocean may have been important contributions to the recent ice extent minima in 2007 and 2012.
Emphasis of Neutrophil-to-Lymphocyte Ratio in Non-Metastatic Renal Cell Carcinoma
Authors: Ceylan Cavit , Camtosun Ahmet , Doluoglu Omer Gokhan , Tasdemir Sedat , Keles Ibrahim , Aglamis Erdogan , Tatar Can Ali
Published: February 2014

Introduction

We investigated the prognostic significance of the neutrophil-to-lymphocyte ratio on overall survival and tumor stage in non-metastatic renal cell carcinoma.

Methods

The records of 229 patients with non-metastatic RCC (T1-4N0M0) were retrospectively reviewed. Patients were classified as group 1 (T1 + T2) and group 2 (T3 + T4). The significance of the differences between the groups in terms of averages and median values were investigated with Student's t-test and Mann-Whitney U test, respectively.

Results

Patients were divided in two as group 1 (T1 + T2) and group 2 (T3 + T4), consisting of 208 and 21 patients, respectively. Between the two groups, the neutrophil-to-lymphocyte ratio (NLR) was found as 2.83 ± 2.15 and 4.79 ± 4.65, respectively (p = 0.02). We found that NLR had a distinctive feature at a cut-off value of 2.9.

Discussion

NLR was higher in local advanced tumors. We observed that the cut-off value of NLR is only associated with tumor volume.
Going to Bed White and Waking Up Arab
Authors: Willett Cynthia , Willett Julie
Published: February 2014

Like lynching and other mass hysterias, xenophobia exemplifies a contagious, collective wave of energy and hedonic quality that can point toward a troubling unpredictability at the core of political and social systems. While earlier studies of mass hysteria and popular discourse assume that cooler heads (aka rational individuals with their logic) could and should regain control over those emotions that are deemed irrational, and that boundaries are assumed healthy only when intact, affect studies pose individuals as nodes of biosocial networks larger than themselves. Thus rather than suggesting that the individual can only prevent societal harm by gaining command and patrolling the borders of an autonomous self, we embrace the notion that affects can exert a positive and transformative force on a social reality that is resistant to top-down policy intervention and any straightforward moral or logical plea.
Fiction as Mapmaking: Moscow as Ivan Bunin's Russian Memory Palace
Authors: Brintlinger Angela
Published: February 2014

In his fiction written from the 1920s through 1940s Ivan Bunin set a number of stories in Moscow, naming specific places, many of which were closed or destroyed after the 1917 Revolution by the Soviet regime or by Nazi bombing during World War II. In so doing, Bunin used Moscow to map the cultural memory of the Russian emigration, with the ancient city of Moscow standing as its “memory palace” while contributing to the “Moscow text.“ In his 1944 story “Cleansing Monday,” in particular, Bunin conducted this mnemonic project on three levels: historical, spiritual, and didactic. He did so for both a Russian readership—his compatriots abroad and potential (future) readers back home—and a foreign audience increasingly interested in Russia. Through close reading of the story, diary entries, and Bunin's biography, this article explores the idea of a memory palace and four specific memory images, comparing Bunin's depiction of Russia to a 1915 depiction by English traveler Stephen Graham.
Politics, Law, and Justice in People's Poland: the Fieldorf File
Authors: Fijalkowski Agata
Published: February 2014

This article examines the case against the Polish resistance fighter August Emil Fieldorf and his subsequent trial. Judicial officials within, or working intimately with, the Soviet secret police made decisions affecting many lives in Poland in 1944-1956. A consideration of the trial proceedings and the backgrounds of selected judicial officials provide a better understanding of the nature of Stalinist justice. Key issues underpinning the trial, related to political contexts, legal maneuverings, and broader considerations surrounding the defendant through the eyes of his persecutors, shed light on the hidden mechanism of Stalinist justice in operation and what constitutes a judicial crime. While its focus is Fieldorf, this article argues that the Polish case study can be instructive in analyzing the ways in which the law was used as a political weapon in other states and regions with similar experiences of totalitarian rule.
The Prince Edward Island–Mayo Clinic Connection: Malcolm B. Dockerty and Lewis B. Woolner
Authors: Wright James R.
Published: February 2014

Context.—Malcolm B. Dockerty and Lewis B. Woolner, 2 preeminent mid–20th-century surgical pathologists, spent their entire careers at the Mayo Clinic. Both were raised in poverty on potato farms only 49 miles apart in Canada's smallest province (Prince Edward Island); both were educated in 1-room schools and graduated as gold medalists from Prince Edward Island's only college and then from Maritime Canada's only medical school; both then trained at the Mayo Clinic.

Objective.—To explore the lives and accomplishments of these 2 important surgical pathologists.

Design.—Standard historiographic methods were used to explore primary and secondary historical sources.

Results.—Both became world-renowned general surgical pathologists, one developing subspecialty expertise in gynecologic pathology and the other in cytopathology, pulmonary pathology, and thyroid/parathyroid pathology. Both were prolific authors with h-indices higher than 40, and between them, they published more than 750 peer-reviewed papers and book chapters. As educators, they trained hundreds of pathology and surgery residents/fellows who disseminated their knowledge around the world. Both were fascinated by poetry from childhood and could quote the classics from memory. One wrote poetry throughout his entire life and even used it to teach pathology and serve as his memoir; the other strongly preferred the classics and in jest called his colleague “a (minor) poet.” Both received postretirement honorary doctorates from their alma maters. Dockerty died in 1987; Woolner celebrates his 100th birthday on November 17, 2013.

Conclusion.—Every pathologist should know of these 2 pioneering surgical pathologists.
A Team-Based Approach to Autopsy Education: Integrating Anatomic and Clinical Pathology at the Rotation Level
Authors: Hébert Tiffany Michele , Maleki Sara , Vasovic Ljiljana V. , Arnold Jeffrey L. , Steinberg Jacob J. , Prystowsky Michael B.
Published: February 2014

Context.—Pathology residency training programs should aim to teach residents to think beyond the compartmentalized data of specific rotations and synthesize data in order to understand the whole clinical picture when interacting with clinicians.

Objective.—To test a collaborative autopsy procedure at Montefiore Medical Center (Bronx, New York), linking residents and attending physicians from anatomic and clinical pathology in the autopsy process from the initial chart review to the final report. Residents consult with clinical pathology colleagues regarding key clinical laboratory findings during the autopsy. This new procedure serves multiple functions: creating a team-based, mutually beneficial educational experience; actively teaching consultative skills; and facilitating more in-depth analysis of the clinical laboratory findings in autopsies.

Design.—An initial trial of the team-based autopsy system was done from November 2010 to December 2012. Residents were then surveyed via questionnaire to evaluate the frequency and perceived usefulness of clinical pathology autopsy consultations.

Results.—Senior residents were the most frequent users of clinical pathology autopsy consultation. The most frequently consulted services were microbiology and chemistry. Eighty-nine percent of the residents found the clinical pathology consultation to be useful in arriving at a final diagnosis and clinicopathologic correlation.

Conclusion.—The team-based autopsy is a novel approach to integration of anatomic and clinical pathology curricula at the rotation level. Residents using this approach develop a more holistic approach to pathology, better preparing them for meaningful consultative interaction with clinicians. This paradigm shift in training positions us to better serve in our increasing role as arbiters of outcomes measures in accountable care organizations.
Anatomic and Clinical Pathology Boot Camps: Filling Pathology-Specific Gaps in Undergraduate Medical Education
Authors: Naritoku Wesley Y. , Vasovic Ljiljana , Steinberg Jacob J. , Prystowsky Michael B. , Powell Suzanne Z.
Published: February 2014

Context.—The Liaison Committee on Medical Education began an initiative to change medical education across the United States in the early 2000s. With the explosion in medical science knowledge, the need arose to teach selected fundamental information both in a contextual and in an active learning manner.

Objective.—To identify ways to address gaps in training and knowledge that became apparent following implementation of learner-centered teaching methods, with devotion of more time to Internet-based learning and less emphasis on face-to-face lecture time. There was a dramatic departure from or de-emphasis of many traditional courses, such as embryology, gross anatomy, microscopic anatomy, and pathology, to the integration of these sciences into system-based active learning courses. This change in medical school curricula produces a medical graduate who hopefully thinks differently but certainly lacks subject-specific knowledge for a variety of medical specialties.

Data Sources.—Pathology residency programs have developed “boot camps” for the initial months of residency training both to provide the necessary foundation of pathology-specific medical science and to introduce basic skills and processes required for practice of anatomic pathology and laboratory medicine. The College of American Pathologists Graduate Medical Education Committee sent a questionnaire out on the Program Directors Section Listserv; the results are discussed and 3 boot camp programs are described.

Conclusions.—Boot camps have 2 purposes: (1) to teach or strengthen knowledge required to practice pathology and (2) to introduce basic skills and processes that will be used during the practitioner's career.
Use of Video Analysis to Support Prospective K-8 Teachers' Noticing of Equitable Practices
Authors: McDuffie Amy Roth , Foote Mary Q. , Drake Corey , Turner Erin , Aguirre Julia , Bartell Tonya Gau , Bolson Catherine
Published: February 2014

Mathematics teacher educators (MTEs) designed and studied a video analysis activity intended to support prospective teachers (PSTs) in learning to notice equitable instructional practices. PSTs from 4 sites (N= 73) engaged in the activity 4 to 5 times during the semester, using a set of 4 “lenses” to analyze teaching and learning as shown in videos. In an earlier analysis of this activity, we found that PSTs increased their depth and expanded their foci in noticing equitable instructional practices (Roth McDuf_ e et al., 2013). In this analysis, we shift the focus to our work as MTEs: We examine our decisions and moves in facilitating the video analysis activity with a focus on equity, and we discuss implications for other MTEs.
Improving Preservice Secondary Mathematics Teachers' Capability With Generic Example Proofs
Authors: Karunakaran Shiv , Freeburn Ben , Konuk Nursen , Arbaugh Fran
Published: February 2014

Preservice mathematics teachers are entrusted with developing their future students' interest in and ability to do mathematics effectively. Various policy documents place an importance on being able to reason about and prove mathematical claims. However, it is not enough for these preservice teachers, and their future students, to have a narrow focus on only one type of proof (demonstration proof), as opposed to other forms of proof, such as generic example proofs or pictorial proofs. This article examines the effectiveness of a course on reasoning and proving on preservice teachers' awareness of and abilities to recognize and construct generic example proofs. The findings support assertions that such a course can and does change preservice teachers' capability with generic example proofs.
Dans la vallée d’Elah : masculinités, narrations et guerre en Irak
Authors: Châteauvert-Gagnon Béatrice
Published: February 2014

Cet article vise à analyser le filmDans la vallée d’Elahà partir d’une perspective théorique féministe de la sécurité internationale, afin de déceler les rapports de genre et de « race » qui sous-tendent la construction de différentes masculinités au sein des discours et des narrations sur la sécurité internationale, la guerre et la militarisation, notamment dans le contexte de la guerre en Irak et des productions culturelles s’y référant. En effet, si le film est critique de plusieurs aspects de la guerre en Irak, il est à se demander si ces critiques ont entraîné une véritable déconstruction des discours genrés et racisés qui légitiment et rendent possibles la militarisation et les guerres, ou si ceux-ci, même critiqués, sont reconduits par la narration du conflit. L’article soutient que la masculinité hégémonique du personnage principal est construite en opposition à une masculinité pervertie par la guerre en Irak chez les jeunes soldats y ayant combattu, limitant la critique à cette guerre spécifique et non à la guerre en général.
Optical optimization of InGaN/GaN edge-emitting lasers with reduced AlGaN cladding thickness
Authors: Czyszanowski Tomasz , Stańczyk Szymon , Kafar Anna , Perlin Piotr
Published: February 2014

This paper presents an extensive numerical analysis and experimental testing of a 420 nm InGaN edge-emitting laser grown on plasmonic GaN substrate. Using a simple transfer matrix method, we investigate the influence of waveguide, bottom AlGaN cladding and substrate parameters on the modal gain and the distribution of the mode. Numerical analysis reveals that using plasmonic substrate the thickness of the n-cladding layer can be reduced to as little as 100 nm. In experimental tests, reducing the AlGaN bottom cladding down to 200 nm is shown to cause no worsening of the threshold parameters.
50 nm AlxOy resistive random access memory array program bit error reduction and high temperature operation
Authors: Ning Sheyang , Iwasaki Tomoko Ogura , Takeuchi Ken
Published: February 2014

In order to decrease program bit error rate (BER) of array-level operation in Al
x
O
y
resistive random access memory (ReRAM), program BERs are compared by using 4 × 4 basic set and reset with verify methods on multiple 1024-bit-pages in 50 nm, mega-bit class ReRAM arrays. Further, by using an optimized reset method, 8.5% total BER reduction is obtained after 104 write cycles due to avoiding under-reset or weak reset and ameliorating over-reset caused wear-out. Then, under-set and over-set are analyzed by tuning the set word line voltage (VWL) of ±0.1 V. Moderate set current shows the best total BER. Finally, 2000 write cycles are applied at 125 and 25 °C, respectively. Reset BER increases 28.5% at 125 °C whereas set BER has little difference, by using the optimized reset method. By applying write cycles over a 25 to 125 to 25 °C temperature variation, immediate reset BER change can be found after the temperature transition.
Assessment of a generalizable methodology to assess learning from manikin-based simulation technology*
Authors: Giuliano Dominic A. , McGregor Marion
Published: February 2014

Objective

This study combined a learning outcomes-based checklist and salient characteristics derived from wisdom-of-crowds theory to test whether differing groups of judges (diversity maximized versus expertise maximized) would be able to appropriately assess videotaped, manikin-based simulation scenarios.

Methods

Two groups of 3 judges scored 9 videos of interns managing a simulated cardiac event. The first group had a diverse range of knowledge of simulation procedures, while the second group was more homogeneous in their knowledge and had greater simulation expertise. All judges viewed 3 types of videos (predebriefing, postdebriefing, and 6 month follow-up) in a blinded fashion and provided their scores independently. Intraclass correlation coefficients (ICCs) were used to assess the reliability of judges as related to group membership. Scores from each group of judges were averaged to determine the impact of group on scores.

Results

Results revealed strong ICCs for both groups of judges (diverse, 0.89; expert, 0.97), with the diverse group of judges having a much wider 95% confidence interval for the ICC. Analysis of variance of the average checklist scores indicated no significant difference between the 2 groups of judges for any of the types of videotapes assessed (F = 0.72, p = .4094). There was, however, a statistically significant difference between the types of videos (F = 14.39, p = .0004), with higher scores at the postdebrief and 6-month follow-up time periods.

Conclusions

Results obtained in this study provide optimism for assessment procedures in simulation using learning outcomes-based checklists and a small panel of judges.
Generalized Biot's theory and Mandel's problem of multiple‐porosity and multiple‐permeability poroelasticity
Authors: Mehrabian Amin , Abousleiman Younane N.
Published: February 2014

This paper finds in Biot's theory of poroelasticity a complete and consistent extension to the general case of multiple‐porosity and multiple‐permeability, fluid‐saturated, and linearly elastic media. The constitutive stress‐strain relations for a medium identified with this extension are presented, and the coefficient matrix of mechanical properties associated with these relations is derived from the corresponding intrinsic properties of its single‐porosity constituents. The closed form analytical solution to Mandel's problem is upgraded to the case being considered in this study. This problem addresses the transient consolidation of a porous elastic slab of rectangular geometry, when confined from the top and bottom. A numerical example solution for shale with laboratory setup of Mandel's problem is provided. Results are compared for the cases of single‐, double‐, and triple‐porosity solutions.
Ice‐melt rates in liquid‐filled cavities during explosive subglacial eruptions
Authors: Woodcock D. C. , Lane S. J. , Gilbert J. S.
Published: February 2014

Subglacial eruptions are often associated with rapid penetration of overlying ice and release of large flow rates of water as jökulhlaups. Observations of recent subglacial eruptions indicate rapid syn‐eruptive ice melting within liquid‐filled subglacial cavities, but quantitative descriptions of possible heat transfer processes need to be developed. Calculations of heat flux from the ice cavity fluid to the melting ice surface indicate that up to 0.6 MW m−2 may be obtained for fluids undergoing single‐phase free convection, similar to minimum estimates of heat flux inferred from observations of recent eruptions. Our model of boiling two‐phase free convection in subglacial cavities indicates that much greater heat fluxes, in the range 3–5 MW m−2, can be obtained in the vent region of the cavity and may be increased further by momentum transfer from the eruption jet. Rapid magma‐water heat transfer from fragmented magma is needed to sustain these heat fluxes. Similar heat fluxes are anticipated for forced convection of subcooled cavity water induced by momentum transfer from an eruption jet. These heat fluxes approach those required to explain jökulhlaup flow rates and rapid ice penetration rates by melting in some, but not all recent eruptions.
Receiver function constraints on crustal seismic velocities and partial melting beneath the Red Sea rift and adjacent regions, Afar Depression
Authors: Reed Cory A. , Almadani Sattam , Gao Stephen S. , Elsheikh Ahmed A. , Cherie Solomon , Abdelsalam Mohamed G. , Thurmond Allison K. , Liu Kelly H.
Published: February 2014

The Afar Depression is an ideal locale for the investigation of crustal processes involved in the transition from continental rifting to oceanic spreading. To provide relatively high resolution images of the crust beneath the Red Sea rift (RSR) represented by the Tendaho graben in the Afar Depression, we deployed an array of 18 broadband seismic stations in 2010 and 2011. Stacking of about 2300 receiver functions from the 18 and several nearby stations along the ~200 km long array reveals an average crustal thickness of 22±4 km, ranging from ~17 km near the RSR axis to 30 km within the overlap zone between the Red Sea and Gulf of Aden rifts. The resulting anomalously high Vp/Vs ratios decrease from 2.40 in the southwest to 1.85 within the overlap zone. We utilize theoretical Vp and melt fraction relationships to obtain an overall highly reduced average crustal Vp of ~5.1 km/s. The melt percentage is about 10% beneath the RSR while the overlap zone contains minor quantities of partial melt. The observed high Vp/Vs values beneath most of the study area indicate widespread partial melting beneath the southwest half of the profile, probably as a result of gradual eastward migration of the RSR axis. Our results also suggest that the current extensional strain in the lower crust beneath the region is diffuse, while the strain field in the upper crust is localized along narrow volcanic segments. These disparate styles of deformation imply a high degree of decoupling between the upper and lower crust.
Savani: A variable resolution whole‐mantle model of anisotropic shear velocity variations based on multiple data sets
Authors: Auer L. , Boschi L. , Becker T. W. , Nissen‐Meyer T. , Giardini D.
Published: February 2014

We present a tomographic model of radially anisotropic shear velocity variations in the Earth's mantle based on a new compilation of previously published data sets and a variable block parameterization, adapted to local raypath density. We employ ray‐theoretical sensitivity functions to relate surface wave and body wave data with radially anisotropic velocity perturbations. Our database includes surface wave phase delays from fundamental modes up to the sixth overtone, measured at periods between 25 and 350 s, as well as cross‐correlation traveltimes of major body wave phases. Before inversion, we apply crustal corrections using the crustal model CRUST2.0, and we account for azimuthal anisotropy in the upper mantle using ray‐theoretical corrections based on a global model of azimuthal anisotropy. While being well correlated with earlier models at long spatial wavelength, our preferred solution, savani, additionally delineates a number of previously unidentified structures due to its improved resolution in areas of dense coverage. This is because the density of the inverse grid ranges between 1.25° in well‐sampled and 5° in poorly sampled regions, allowing us to resolve regional structure better than it is typically the case in global S wave tomography. Our model highlights (i) a distinct ocean‐continent anisotropic signature in the uppermost mantle, (ii) an oceanic peak in above average ξ<1 which is shallower than in previous models and thus in better agreement with estimates of lithosphere thickness, and (iii) a long‐wavelength pattern of ξ<1 associated with the large low‐shear velocity provinces in the lowermost mantle.
Constraining the area of rapid and deep‐seated exhumation at the St. Elias syntaxis, Southeast Alaska, with detrital zircon fission‐track analysis
Authors: Falkowski Sarah , Enkelmann Eva , Ehlers Todd A.
Published: February 2014

The Chugach‐St. Elias orogen, Southeast Alaska/Southwest Yukon, formed in response to the ongoing Yakutat microplate subduction‐collision with the North American Plate. Due to heavy glaciation, the region is a prime location to study active convergent orogenesis and climate‐tectonic interactions. This study focuses on the long‐term distribution of deformation in the St. Elias syntaxis area, where dextral motion along the plate‐bounding Fairweather Fault transitions into convergence. We present 2718 new zircon fission‐track single‐grain ages from 26 glaciofluvial outwash samples. The grain ages range from 293 Ma to 0.2 Ma, and each sample contains two to five age populations with peaks between 267 ± 64 Ma and 1.2 ± 0.7 Ma (1σ). The rocks of the Yakutat microplate are dominated by latest Cretaceous and Eocene fission‐track ages, while the rocks of the North American Plate in the syntaxis region reveal two exhumation phases at ~5.1 Ma and ~2.7 Ma. The spatial pattern of ≤5 Ma cooling ages shows that the area of rapid and deep exhumation at the St. Elias syntaxis is more extensive than previously known and confined to the south by the Fairweather Fault, to the west by the Seward Glacier catchment, and to the east possibly by the inferred Connector Fault. The area seems to be ~4800 km2 large and may extend farther to the north. The new zircon fission‐track data further suggest a transpressional plate boundary since ~30 Ma and the onset of plate collision 15–12 Ma.
A convex optimization algorithm for frequency‐domain identification in the v‐gap metric
Authors: Geng Li‐Hui , Cui Shi‐Gang , Zhao Li , Lin Hai‐Qi
Published: February 2014

This paper proposes a convex optimization algorithm to minimize the v‐gap metric for parameter estimation of a SISO system using frequency‐domain measurements. According to a geometrical interpretation for this metric, its evaluation for two SISO linear systems is the supreme of sine values of the apertures between their normalized right graph symbols. As a result, the minimization of the v‐gap metric becomes that of the maximum of sine values of those apertures at sampling frequencies and can be efficiently solved by a sequence of feasibility problems with a decreasing line search. Compared with the related algorithms, the proposed one has global convergence and much lower computational loads. Finally, a numerical simulation shows the effectiveness of the proposed algorithm. Copyright © 2014 John Wiley & Sons, Ltd.