bluuebunny/crossref_metadata_2025 huggingface dataset:
The transverse runout of a rotating flexible disc under stationary sliders
Authors: Pei Yong-Chen , He Ling , He Feng-Jiang
Published: February 2009

The governing equation of a rotating flexible disc under stationary sliders is modelled under consideration of the initial transverse runout of the disc. Natural frequency and stability of the system is studied and checked, and steady-state response is obtained. The effects of system parameters on the steady-state amplitude of the sliders are analysed and resonance induced by the sliders is discovered. The decrease of the number of nodal diameters of the initial transverse runout and slider mass, and the increase of disc damping, slider damping, and natural frequency and friction force at the disc—slider interface, can be used to suppress the amplitude.
Disc cam mechanisms with concave-faced followers
Authors: Wu L-I , Liu C-H , Chen T-W
Published: February 2009

This article proposes an uncommon follower, a concave-faced follower, for a disc cam mechanism and also presents an analytical approach for determining the cam profile. A disc cam mechanism with a concave-faced follower can have the advantage of lower contact stress over that with a flat-faced follower. Two examples are provided to illustrate the nature and capability of reducing contact stress of this uncommon follower.
The drag work minimization path for a flying object with altitude-dependent drag parameters
Authors: Pakdemirli M
Published: February 2009

The work due to drag force for a flying object is considered. The density of the fluid, the drag coefficient, and the velocity are all assumed to be functions of altitude. The differential equation describing the path for minimum drag work is derived using variational calculus. A special form of this equation describing exponentially decaying fluid density is then considered. The equation is cast into a dimensionless form. One of the dimensionless parameters is the final height/final distance and the other is related to the exponential decay of the density. An analytical solution for the path is found by solving the equation. The analytical solution is approximated using Taylor series expansions and contrasted with the perturbation solution. The effect of dimensionless parameters on the path is discussed.
Automated cell disruption is a reliable and effective method of isolating RNA from fresh snap-frozen normal and malignant oral mucosa samples
Authors: Van der Vorst Sébastien , Dekairelle Anne-France , Irenge Léonid , Hamoir Marc , Robert Annie , Gala Jean-Luc
Published: February 2009

: This study compared automated vs. manual tissue grinding in terms of RNA yield obtained from oral mucosa biopsies.

: A total of 20 patients undergoing uvulectomy for sleep-related disorders and 10 patients undergoing biopsy for head and neck squamous cell carcinoma were enrolled in the study. Samples were collected, snap-frozen in liquid nitrogen, and divided into two parts of similar weight. Sample grinding was performed on one sample from each pair, either manually or using an automated cell disruptor. The performance and efficacy of each homogenization approach was compared in terms of total RNA yield (spectrophotometry, fluorometry), mRNA quantity [densitometry of specific

: Although spectrophotometry and fluorometry results were comparable for both homogenization methods,

: Automated tissue homogenization appears to be a versatile, quick, and reliable method of cell disruption and is especially useful in the case of small malignant samples, which show unreliable results when processed by manual homogenization.

Clin Chem Lab Med 2009;47:294–301.
Adaptive Reibkraftkompensation zur modellbasierten Positionsregelung von Nanopositionier- und NanomessmaschinenModel Based Position Control of Nanopositioning- and Nanomeasuring Machines Using an Adaptive Friction Cancellation Approach
Authors: Amthor Arvid , Zschäck Stephan , Ament Christoph
Published: February 2009

In der vorliegenden Arbeit wird eine modellbasierte Trajektorienfolgeregelung für Positionier-aufgaben mit Nanometerauflösung vorgestellt. Hierzu wird die dominante Störgröße Reibung durch ein physikalisch motiviertes Reibmodell nachgebildet. Dieses Modell wird auf Grundlage von experimentellen Daten offline identifiziert und anschließend in einer Vorsteuerung eingesetzt. Während der Online-Phase werden die linearen Modellparameter mittels einer rekursiven Regression adaptiert, um positionsabhängige Reibkraftschwankungen zu kompensieren. Es kann in dieser Arbeit gezeigt werden, dass verglichen mit einer klassischen Regelstrategie eine modellbasierte Regelung in der Lage ist, die Dynamik des geregelten Systems signifikant zu erhöhen. Darüber hinaus kann die Regelabweichung deutlich gesenkt werden.
Schnelle Regelung von linearen Systemen mit StellgrößenbeschränkungenFast Control of Linear Systems with Input Constraints
Authors: Lens Hendrik , Adamy Jürgen
Published: February 2009

In diesem Artikel wird eine nichtlineare Zustandsrückführung für Regelstrecken mit linearer Dynamik und einer Stellgrößenbeschränkung vorgestellt. Die Methode ermöglicht sehr schnelle Regelvorgänge. Erreicht wird dies durch die Verknüpfung sättigender und weicher strukturvariabler Regler. Es wird ein effizientes, LMI-basiertes Entwurfsverfahren zur Bestimmung der Reglerparameter vorgestellt. Bei Nachoptimierung der Parameter mittels Suchverfahren erreicht die Regelung eine Güte, die sehr nah an die zeitoptimale Lösung heranreicht.
Über Ontologien und deren Anwendung in der AutomatisierungstechnikTowards Ontologies and Their Application in Automation Engineering
Authors: Däubler Lorenz
Published: February 2009

Der Beitrag beschäftigt sich mit dem Begriff der Ontologie und seiner Anwendung in der Automatisierungstechnik. Augenmerk liegt auf den formalen Ontologiedefinitionen von Gruber und Guarino. Als Anwendung wird die Überprüfung und Identifikation von strukturellen Ähnlichkeiten (Morphismen) diskutiert, die zwischen den Ontologien unterschiedlicher Gegenstandsbereiche bestehen.
Pervasive University – A Technical PerspectiveDie Pervasive University aus technischer Perspektive
Authors: Tavangarian Djamshid , Lucke Ulrike
Published: February 2009

The article proposes a definition for the term “Pervasive University”. It discusses the idea, history, and implications of this architecture. Furthermore, some technical prerequisites from a technical point of view are stated: Pervasive Computing itself as well as Service-Oriented Architecture, Self Organization, and Peer-to-Peer Computing. This leads to a roadmap for the implementation of a Pervasive University.
Federated Identity Management as a Basis for Integrated Information ManagementFöderiertes Identitätsmanagement als Fundament eines Integrierten Informationsmanagements
Authors: Schell Frank , Höllrigl Thorsten , Hartenstein Hannes
Published: February 2009

Identity management is a key component of the authorization mechanisms that govern access to the diverse IT services offered at pervasive universities. The federation paradigm proves to be a useful tool for establishing an integrated identity management system in this setting. The main principles of federations, i. e., decentralization, subsidiarity, and mutual respect among the partners, can be applied to develop a 'bi-level′ approach to identity management. For reasons that will be explained, a bi-level system is more likely to be successful at a pervasive university than the more standard 'centralized′ approach.
Kommunikationsstrukturen in einer pervasiven Lehr- und LernumgebungAspects of Communication Systems for Pervasive Learning Environments
Authors: Hegering Heinz-Gerd , Läpple Alfred , Reiser Helmut
Published: February 2009

Der Begriff Pervasive Universität ist bisher nicht klar definiert. Deshalb setzt sich der Beitrag zunächst mit relevanten Lerntypen auseinander, die für die Ausprägung der benötigten Kommunikationsinfrastrukturen wichtig sind. Anhand der Lerntypen werden die Anforderungen analysiert. Neu sind neben Virtualisierung und Personalisierung der Lehr- und Lernumgebungen der ubiquitäre Zugriff und als Folge eine Unterstützung aller Mobilitätsformen und kontextsensitiver Dienste. Der Beitrag macht deutlich, dass für die Betrachtung von Kommunikationsstrukturen eine integrale Betrachtung und Einbettung in universitäre Betriebs- und Organisationsprozesse unverzichtbar ist.
Pervasive Learning – A Question of ContextPervasive Learning – Eine Frage des Kontexts
Authors: Helms Niels Henrik , Larsen Lasse Juel
Published: February 2009

Modern learners have access to almost unlimited resources of information and they can obtain, share and develop knowledge through a multitude of different media. Education is a way of accessing and developing knowledge and it has gotten a new meaning. Education is now about how you handle knowledge, it is not a specific place where you can access scarce information. Pervasive or ubiquitous communication opens up for taking the organizing and design of learning landscapes a step further. Furthermore it calls for theoretical developments, which can open up for a deeper understanding of the relationship between emerging contexts, design of contexts and learning.
Effects of Transportation and Other Factors on Survival Estimates of Juvenile Salmonids in the Unimpounded Lower Columbia River
Authors: Clemens Benjamin J. , Clements Shaun P. , Karnowski Mark D. , Jepsen David B. , Gitelman Alix I. , Schreck Carl B.
Published: February 2009

We estimated the survival of juvenile salmonids out‐migrating through the lower Columbia River to the Pacific Ocean. We tested the null hypotheses that no association exists between survival and transportation type (including barge transportation and in‐river migration with no transportation), release date, river flow, mean body weight, and tag type. During 2002‐2004, spring‐summer (SS) and fall Chinook salmon Oncorhynchus tshawytscha and steelhead O. mykiss were implanted with uniquely coded radio or acoustic transmitter tags and released during the early, middle, and late out‐migration periods. A series of receiver lines were used to detect these fish and estimate survival. Estimated survival varied considerably with transportation type and release date for fall Chinook salmon and steelhead, but the results were dependent upon year. Estimated survival between the lowermost dam (Bonneville Dam) and the upper estuary (river kilometer 46) was relatively high for SS Chinook salmon and steelhead, whereas estimates for fall Chinook salmon were comparatively low. This order of high to low survival for SS Chinook salmon, steelhead, and fall Chinook salmon corresponds with the chronology of out‐migration timing and waning river flows. After accounting for a number of factors, estimated survival between Bonneville Dam and the upper‐estuary site did not differ significantly between steelhead that were barged and those that migrated in‐river during 2002 and 2003. Conversely, estimated survival to the upper‐estuary site was quite low for barged fall Chinook salmon in comparison with fish migrating in‐river during the middle and late release dates in 2003. Hypotheses for the low survival of barged fall Chinook salmon are presented and discussed.
Using a Passive Acoustic Survey to Identify Spotted Seatrout Spawning Sites and Associated Habitat in Tampa Bay, Florida
Authors: Walters Sarah , Lowerre‐Barbieri Susan , Bickford Joel , Mann David
Published: February 2009

The spatial distribution of spawning activity can affect the reproductive success of certain fishes, and locating the key areas is critical to accurately assessing and managing their populations. We determined estuarine spawning locations for spotted seatrout Cynoscion nebulosus during the 2004 summer spawning season in Tampa Bay, Florida, using a passive acoustic survey. Sound production was evaluated at each of 754 randomly selected stations for the number of individuals calling and ranged from 1‐2 individuals to large aggregations. Spawning was identified by large aggregation sounds and was detected at 8% of the selected stations. There was seasonal variability in spawning, as spawning areas were inconsistently used throughout the season. Spatially, spawning occurred in all regions of the bay except for the Hillsborough Bay region. Most spawning took place in lower Tampa Bay and the eastern portion of the middle bay. Spawning occurred most frequently near the shoreline in areas of relatively high dissolved oxygen and in association with submerged aquatic vegetation. The variability in spawning habitat, as exhibited by both the disproportionate distribution of spawning sites across Tampa Bay and the inconsistent use of spawning sites, may serve to increase the resilience of the stock. As management directives evolve to encompass habitat‐focused strategies, surveys such as this one can supply data necessary for the creation of meaningful ecosystem‐based management plans.
Temporal Variation in Trout Populations: Implications for Monitoring and Trend Detection
Authors: Dauwalter Daniel C. , Rahel Frank J. , Gerow Kenneth G.
Published: February 2009

We summarized the temporal variation in populations of inland trout Salmo, Salvelinus, and Oncorhynchus spp. from streams in North America and determined the statistical power to detect trends over time. The coefficients of variation in abundance averaged 49% (SD = 27%; range = 15‐108%) over time for all ages of trout. Temporal variation was lower when more age‐classes were monitored, but whether abundance or biomass was more variable differed among populations. Detecting population trends was difficult when using the traditional α = 0.05 criterion. For example, detecting a 5% annual decline with good power (1 ‐ β ≥ 0.80) would require about 20 years if only one site were monitored. Even when α was relaxed to 0.20, 15 years were required to detect a 5% annual decline when the variation was average. Using a network of sites improved the ability to detect changes: A 5% annual decline at α = 0.05 could be detected in 10 years when 30 sites were monitored. For high‐value populations, it may require relaxing α to ensure that declines are detected, even if this increases the risk of claiming change when none has occurred and thus undertaking unnecessary management action. For example, a 5% annual decline could be detected with good power (≥0.80) in 8 years when a network of 30 sites is monitored at α = 0.20. Thus, biologists should monitor the least‐variable component of a population, monitor a network of sites, and increase α for species of concern to ensure that real population trends are detected. Estimates of trend parameters (and their uncertainty) should be considered in addition to whether or not a statistical test for trend is significant. A pilot study or existing data can help estimate the variation that is typical of the population(s) to be monitored, determine whether trends can be reliably detected, and identify how much risk needs to be incurred to detect trends.
Effects of Gastric and Surgical Insertions of Dummy Ultrasonic Transmitters on Juvenile Chinook Salmon in Seawater
Authors: Hall J. E. , Chamberlin J. , Kagley A. N. , Greene C. , Fresh K. L.
Published: February 2009

The objective of this study was to develop guidance for tagging methods for juvenile Chinook salmon Oncorhynchus tshawytscha in their first ocean year by evaluating the effects of tagging during this critical life stage. We compared survival over 42 d among juvenile hatchery Chinook salmon receiving surgically implanted dummy ultrasonic transmitters (equivalent to VEMCO V7‐1 L tags) ranging from 2.6% to 8.8% of body mass with that of fish receiving gastrically implanted tags. Survival was significantly lower in fish receiving gastrically implanted transmitters (21%) than for the gastric‐sham (66%), surgery (61%), surgery‐sham (58%), and control treatments (90%). Survival was also significantly higher in the control treatment than in all other treatments. The results of this study indicate that surgical insertion into the peritoneal cavity is the preferred method of transmitter implantation in juvenile Chinook salmon in their first ocean year and that the transmitters should be less than 5.8% of the fish's body mass to reduce transmitter‐related mortality.
Effects of Fish Size, Habitat, Flow, and Density on Capture Probabilities of Age‐0 Rainbow Trout Estimated from Electrofishing at Discrete Sites in a Large River
Authors: Korman Josh , Yard Mike , Walters Carl , Coggins Lewis G.
Published: February 2009

We estimated size‐specific capture probabilities of age‐0 rainbow troutOncorhynchus mykissin the Lee's Ferry Reach of the Colorado River, Arizona, by backpack and boat electrofishing at discrete shoreline sites using both depletion and mark‐recapture experiments. Our objectives were to evaluate the feasibility of estimating capture probability for juvenile fish in larger rivers; to determine how it is influenced by fish size, habitat, flow, density, and recovery period; and to test population closure assumptions. There was no mortality among the 351 rainbow trout that were captured by electrofishing, marked, and held for 24 h. Of a total of 2,966 fish that were marked and released, only 0.61% were captured outside of mark‐recapture sites, and total emigration from mark‐recapture sites was 2.2‐2.6%. These data strongly suggest that populations within discrete sites can be treated as effectively closed for the 24‐h period between marking and recapture. Eighty percent of capture probability estimates from 66 depletion experiments and 42 mark‐recapture experiments ranged from 0.28 to 0.75 and from 0.17 to 0.45, respectively, and the average coefficient of variation of estimates was 0.26. There was strong support for a fish size‐capture probability relationship that accounted for the differences in vulnerability across habitat types. Smaller fish were less vulnerable in high‐angle shorelines that were sampled by boat electrofishing. There was little support for capture probability models that accounted for within‐day and across‐month variation in flow. The effects of fish density on capture probability were challenging to discern, variable among habitat types and estimation methodologies, and confounded with the effect of fish size. As capture probability estimates were generally precise and the closure assumption was met, our results demonstrate that electrofishing‐based mark‐recapture experiments at discrete sites can be used to estimate the abundance of juvenile fish in large rivers.
Effects of Hydropeaking on Nearshore Habitat Use and Growth of Age‐0 Rainbow Trout in a Large Regulated River
Authors: Korman Josh , Campana Steven E.
Published: February 2009

We evaluated the effects of hourly variation in flow caused by power load following at Glen Canyon Dam (“hydropeaking”) on the nearshore habitat use and growth of age‐0 rainbow trout Oncorhynchus mykiss downstream from the dam in the Colorado River, Arizona. Reduction in the extent of hydropeaking is a common element of restoration efforts in regulated rivers, but empirical support for such a practice is limited. Our assessment was based on a comparison of abundance in shoreline areas determined by electrofishing at different flows as well as analysis of otolith microstructure. The catch rates of age‐0 rainbow trout in nearshore areas were at least two‐ to fourfold higher at the daily minimum flow than at the daily maximum, indicating that most age‐0 rainbow trout do not maintain their position within immediate shoreline areas when flows are high. A striping pattern, identified by the presence of atypical daily increments formed every 7 d, was evident in over 50% of the 259 otoliths examined in 2003 but in only 6% of the 334 examined in 2004. The weekly pattern corresponded to a reduction in the extent of hourly flow fluctuations on Sundays during the growing season, which occurred in 2003 but not in 2004. The atypical increments were 25% wider than the adjacent increments and were indicative of significant (F15, 235 = 19.2, P < 0.0001) short‐term increases in otolith growth. The somatic growth rate among fish with otoliths where striping was present (11.2 mm/month) was slightly greater than that among fish with otoliths without striping (10.8 mm/month), but the difference was not significant. We provide evidence suggesting that otolith growth improved on Sundays in 2003 because it was the only day of the week when most age‐0 fish were found in immediate shoreline areas, where higher water temperatures and lower velocities provided better growing conditions.
Influence of Spring Floods on Year‐Class Strength of Fall‐ and Spring‐Spawning Salmonids in Catskill Mountain Streams
Authors: Warren Dana R. , Ernst Anne G. , Baldigo Barry P.
Published: February 2009

Climate change in northeastern North America has already led to earlier snowmelt and increases in the magnitude and frequency of large storms; associated changes are expected to intensify over the next several decades. Alterations in flooding regimes associated with climate change have the potential to negatively affect fish species with earlier fry emergence and alter the fish communities in tributary streams where fall‐ and spring‐spawning salmonids coexist or where there may be invasion potential by a given species. This 6‐year study (2002‐2007) assessed the effects of the timing and magnitude of spring flood events on year‐class strength in sympatric populations of fall‐spawning brook troutSalvelinus fontinalis, fall‐spawning brown troutSalmo trutta, and spring‐spawning rainbow troutOncorhynchus mykiss. The relative abundances of young‐of‐year (age‐0) and age‐1 fall‐ and spring‐spawning salmonids were documented for 4 and 6 years in streams from two watersheds in the Catskill Mountains, New York. Fall‐spawning age‐0 fish dominated in all years except 2005. In spring 2005 a large flood occurred at nearly the same time of year as the 2004 snowmelt, but discharge was nearly an order of magnitude greater. The dominant salmonid for that year‐class shifted to rainbow trout, but fall‐spawned age‐0 trout were again dominant in the following year. These results indicate that the timing and magnitude of spring high flows can increase the relative abundance of spring‐spawning age‐0 salmonids, decrease the abundance of fall‐spawning age‐0 salmonids, or both. The overall dominance of fall‐spawned fish appears to be resilient as long as displacing floods occur a few years apart. If the trend toward larger, more frequent, and earlier spring floods continues, differential survival of age‐0 fish of the three salmonid species will probably cause shifts in the dominant trout species in many Catskill Mountain streams.
Genetic Stock Composition of Subyearling Chinook Salmon in Seasonal Floodplain Wetlands of the Lower Willamette River, Oregon
Authors: Teel David J. , Baker Cyndi , Kuligowski David R. , Friesen Thomas A. , Shields Barbara
Published: February 2009

We used genetic identification methods to examine the stock composition of subyearling Chinook salmon Oncorhynchus tshawytscha in floodplain wetland and main‐stem habitats of the lower Willamette River, Oregon. Using a microsatellite DNA baseline of 13 standardized loci and 30 Columbia River basin populations, we analyzed 280 subyearlings collected in winter and spring 2005‐2006 from wetland and main‐stem river sites. Genetic stock identification analysis indicated that spring Chinook salmon originating from the Willamette River made up a substantial proportion of the samples and contributed 16‐71% to sample mixtures representing the wetland habitat sites. Fall Chinook salmon from lower Columbia River sources were also present and contributed 58% of winter samples. Spring Chinook salmon from lower Columbia River populations were present in both wetland (17%) and river (16%) samples in spring 2005, and subyearlings from summer‐fall‐run populations in the middle and upper Columbia River contributed to spring wetland samples in 2006 (26%). The results suggest that floodplain restoration projects intended to improve fish habitats during winter and spring periods in the lower Willamette River may benefit Chinook salmon populations from the upper Willamette River, lower Columbia River, and upper Columbia River summer‐fall evolutionarily significant units.
Approval Summary: Imatinib Mesylate in the Treatment of Metastatic and/or Unresectable Malignant Gastrointestinal Stromal Tumors
Authors: Cohen Martin H. , Farrell Ann , Justice Robert , Pazdur Richard
Published: February 2009

Learning Objectives

Identify the appropriate imatinib dose for patients after diagnosis and patients after disease progression. Differentiate between the FDA’s acclerated and regular drug approval processes and their impact on patient care. Demonstrate familiarity with the safety profile of imatinib.

This article is available for continuing medical education credit at CME.TheOncologist.com.
Identification and action of N-myc downstream regulated gene 4 A2 in rat pancreas
Authors: Wang Jia Fang , Hill David J
Published: February 2009

Pancreatic islets and acinar tissue develop from duct epithelium and share expression of several transcription factors and other molecular markers also involved with the development of neural tissues. We examined rat pancreatic tissue from fetal life until adulthood for the expression of N-myc downstream regulated gene 4 (Ndrg4), a gene shown to be expressed during neuronal cell differentiation. Isolated pancreatic ducts from neonatal rats were maintained in culture and gave rise to clusters of cells expressing nestin (NES) and PDX-1, which subsequently contained immunoreactive glucagon. Using reverse transcription PCR (RT-PCR), we identified mRNA expression and immunoreactive protein presence for NDRG4 in cultured duct-derived cells, and brain of neonatal rats. By PCR cloning of the ductal cell-derived DNA the molecular form of NDRG4 expressed in pancreatic ducts and ARIP rat pancreatic cells was identified as NDRG4A2, and its presence in intact pancreas of fetal and neonatal rats was demonstrated by immunohistochemistry. Incubation of ARIP cells with glucagon-like polypeptide-1 (GLP-1), increased the expression of NDRG4A2 and PDX-1, while decreasing DNA synthesis and promoting the appearance of glucagon-positive cells. This inhibitory effect of GLP-1 on DNA synthesis and the stimulatory effect on endocrine differentiation were reversed when the translation of NDRG4A2 was prevented using siRNA. These findings indicate that NDRG4A2 is expressed in pancreatic duct cells under GLP-1 control and may be related to a reduction in proliferation and the onset of the pancreas cell differentiation.
Early postnatal oestradiol exposure causes insulin resistance and signs of inflammation in circulation and skeletal muscle
Authors: Alexanderson Camilla , Eriksson Elias , Stener-Victorin Elisabet , Lönn Malin , Holmäng Agneta
Published: February 2009

Early postnatal events can predispose to metabolic and endocrine disease in adulthood. In this study, we evaluated the programming effects of a single early postnatal oestradiol injection on insulin sensitivity in adult female rats. We also assessed the expression of genes involved in inflammation and glucose metabolism in skeletal muscle and adipose tissue and analysed circulating inflammation markers as possible mediators of insulin resistance. Neonatal oestradiol exposure reduced insulin sensitivity and increased plasma levels of monocyte chemoattractant protein-1 (MCP-1) and soluble intercellular adhesion molecule-1. In skeletal muscle, oestradiol increased the expression of genes encoding complement component 3 (C3), Mcp-1, retinol binding protein-4 (Rbp4) and transforming growth factor β1 (Tgfβ1). C3 and MCP-1 are both related to insulin resistance, and C3, MCP-1 and TGFβ1 are also involved in inflammation. Expression of genes encoding glucose transporter-4 (Glut 4), carnitine-palmitoyl transferase 1b (Cpt1b), peroxisome proliferator-activated receptor δ (Ppard) and uncoupling protein 3 (Ucp3), which are connected to glucose uptake, lipid oxidation, and energy uncoupling, was down regulated. Expression of several inflammatory genes in skeletal muscle correlated negatively with whole-body insulin sensitivity. In s.c. inguinal adipose tissue, expression of Tgfβ1, Ppard and C3 was decreased, while expression of Rbp4 and Cpt1b was increased. Inguinal adipose tissue weight was increased but adipocyte size was unaltered, suggesting an increased number of adipocytes. We suggest that early neonatal oestrogen exposure may reduce insulin sensitivity by inducing chronic, low-grade systemic and skeletal muscle inflammation and disturbances of glucose and lipid metabolism in skeletal muscle in adulthood.
Dryland Crop Yields and Soil Organic Matter as Influenced by Long‐Term Tillage and Cropping Sequence
Authors: Sainju Upendra M. , Lenssen Andrew W. , Caesar‐TonThat Thecan , Evans Robert G.
Published: February 2009

Novel management practices are needed to improve the declining dryland crop yields and soil organic matter contents using conventional farming practices in the northern Great Plains. We evaluated the 21‐yr effect of tillage and cropping sequence on dryland grain and biomass (stems + leaves) yields of spring wheat (Triticum aestivum L.), barley (Hordeum vulgare L.), and pea (Pisum sativum L.) and soil organic matter at the 0‐ to 20‐cm depth in eastern Montana, USA. Treatments were no‐tilled continuous spring wheat (NTCW), spring‐tilled continuous spring wheat (STCW), fall‐ and spring‐tilled continuous spring wheat (FSTCW), fall‐ and spring‐tilled spring wheat‐barley (1984–1999) followed by spring wheat‐pea (2000–2004) (FSTW‐B/P), and the conventional spring‐tilled spring wheat‐fallow (STW‐F). Spring wheat grain and biomass yields increased with crop growing season precipitation (GSP) and were greater in STW‐F than in FSTCW and FSTW‐B/P when GSP was <250 mm. Although mean grain and biomass yields were greater, annualized yields were lower in STW‐F than in other treatments. In FSTW‐B/P, barley and pea grain and biomass yields also increased with increased GSP. Soil organic C and total N were lower in STW‐F than in other treatments and linearly related (R2 = 0.64 to 0.78) with total annualized biomass residue returned to the soil from 1984 to 2004. Alternate‐year summer fallowing increased spring wheat grain and biomass yields compared with annual cropping but reduced annualized yields and soil organic matter. For sustaining dryland crop yields and soil organic matter, no‐tillage with annual cropping system can be adopted in the northern Great Plains.
No‐Till Corn after Bromegrass: Effect on Soil Carbon and Soil Aggregates
Authors: Follett Ronald F. , Varvel Gary E. , Kimble John M. , Vogel Kenneth P.
Published: February 2009

Grasslands in the Conservation Reserve Program (CRP) in the USA may be converted to grain crops for bioenergy. The effect of no‐till conversion of a smooth bromegrass (Bromus inermis Leyss) grassland to no‐till corn (Zea mays L.) production on soil organic carbon (SOC) in the western Corn Belt was monitored for over 6 yr. A different 13C/12C isotope signature is imparted to SOC by C4 plants including corn versus C3 plants such as bromegrass. Changes in C isotope ratios in SOC in three soil depths (0‐ to 5‐, 5–10, and 10–30 cm) by particle size was also monitored during ∼6.5 yr of no‐till corn production at two different N levels (60 and 120 kg ha−1). Soil was collected eight times during the study from the 0‐ to 5‐ and 5‐ to 10‐cm depths, and at four of these times from the 10‐ to 30‐cm depth from each of the N rate replicates. Because fertilizer N had no significant effect over years on any of the aboveground biomass production variables, the data from both N treatments was combined for regression analysis to determine the effects of years of no‐till corn production on SOC variables. Total SOC did not change significantly at any depth during the study, but there was a significant change in the source of the SOC. Total C4‐C increased over this time, while C3‐C decreased in the 0‐ to 5‐ and 5‐ to 10‐cm depth, while neither changed in the 10‐ to 30‐cm depth. In the 0‐ to 5‐ and 5‐ to 10‐cm depths, largest loss of C3‐C was from 2‐mm aggregates, while largest increases in C4‐C were in the 1‐, 0.5‐, 0.25‐, and 0.125‐mm aggregates. If CRP grasslands are converted to grain crop production, the data from this study strongly support the use of no‐till farming practices as a method of conserving the SOC that was sequestered during the time period that the land was in the CRP.
Characterizing and Classifying Variability in Corn Yield Response to Nitrogen Fertilization on Subfield and Field Scales
Authors: Kyveryga P. M. , Blackmer A. M. , Zhang J.
Published: February 2009

Marked spatial and temporal variability in yield response to N fertilizer observed in individual yield response trials creates a high degree of uncertainty when estimating economic optimum rates (EORs) of N for a group of trials and when extrapolating these rates from one location to another. A survey was conducted to characterize and classify variability in yield response to N on subfield and field scales. Fertilizer N was applied at five rates (56, 84, 112, 140, and 168 kg N ha−1) in many (6–12) replicated strips within three 18‐ to 24‐ha no‐till fields during two corn (Zea mays L.) growing seasons. Yield responses or yield differences between two adjacent strips were measured in 22 to 25 grid cells ha−1 within each field. Cumulative probability distributions (CPDs) were used to estimate the probability that a given N rate produces a yield response less or equal to a specified quantity. The yield responses were classified into potential categories with different N fertilizer requirements using apparent soil electrical conductivity (ECa), digital soil map units, and relative elevation. Analysis indicated that the classifications explained <3% variability in yield response to N applied in the near‐optimal range, where probabilities of receiving positive and negative marginal returns were the same. Presenting probabilities of yield response observed at different ranges of N fertilization may provide the basis for assessing the uncertainty associated with the variable effects of weather and variable supply of N when assessing economic risk and benefits of N fertilization in large‐scale on‐farm studies.
Notetaking and Writing from Hypertexts in L1 and L2
Authors: Barbier Marie-Laure , Piolat Annie , Roussey Jean-Yves , Raby Françoise
Published: February 2009

This study analyzes the cognitive effort and linguistic procedures of sixty students using information taken from an experimental website in L1 (French) and in L2 (English). The students navigated on the website and took notes on paper or with a word processor. A triple-task paradigm was used to estimate the cognitive load of reading, notetaking, and writing processes in L2. The students had to perform two additional tasks while a main task (notetaking, for example) was being carried out. They had to react as fast as possible to sound signals sent out at random intervals. They also had to identify what they were doing at the time the sound signal was heard (reading, notetaking, or writing). The study focuses on the way the students managed their cognitive resources while exploring the website, selecting and writing down the ideas they considered useful, and reconstructing them later when producing their own text. Surprisingly, no difference in cognitive load was observed between L1 and L2. By relying almost exclusively on the copy and paste functions to retrieve information from the website, the participants using a word processor in L2 succeeded in making reading a less costly activity, and they performed similarly to the notetakers in L1. The students’ difficulties in L2 became apparent only in the paper condition. The strategies and linguistic procedures of the students are described and related to the ways teachers can approach the new dimensions of notetaking and writing with a computer.
Developmental Stages in Advanced SLA
Authors: Ene Estela
Published: February 2009

Second Language Acquisition (SLA) researchers have yet to map the developmental stages language learners go through as they approach the target language. In studies of English as a Second Language (ESL) writing, the term 'advanced learner' has been applied indiscriminately to learners ranging from freshman ESL composition to graduate students. There is a need to examine the advanced stages of SLA in order to refine SLA theories and pedagogical approaches. A corpus of texts written by non-native English-speaking doctoral students in applied linguistics from several linguistic backgrounds was analyzed to determine the texts’ lexical, morphological and syntactic fluency, accuracy and complexity. A sub-corpus of papers by native-English-speaking peers was used for comparison. The texts were strictly-timed and loosely-timed exams written 2 to 3 years apart. Surveys and interviews were also conducted. Based on findings, the study defines data-based criteria that distinguish four quantitatively and qualitatively distinct developmental stages: the advanced, highly advanced, near-native, and native-like stages. Advanced learners make more frequent and varied errors which can be explained by transfer from the first language. Native-like writers make few errors that can be explained by overgeneralization of conventions from informal English and working memory limitations (similar to native speakers’ errors). The study suggests that SLA is a process of transfer followed by relearning of morpho-syntactic specifications (Herschensohn, 2000), with syntax being used with the greatest accuracy (Bardovi-Harlig & Bofman, 1989) and lexicon with the least. The relationships between accuracy and other social and cognitive factors are considered, and pedagogical recommendations are made.
Learner Agency and Identity in Second Language Writing
Authors: Lee Heekyeong
Published: February 2009

In this paper, I provide a critical discussion about the socio-cultural-historical dimension of a student’s struggle in the processes of learning academic writing in second language (L2). Some teachers or researchers may assume that L2 students often struggle because they do not know or do not understand the information they are taught. Therefore, teachers may feel that it is their duty to explicitly teach the information to students. I argue that some L2 students’ difficulties in their academic writing processes should not only be viewed as due to their limited proficiency of language or motivation to learn. Rather, L2 student writers’ struggles can be influenced by the process of negotiating learner agency and identity in their multiple social worlds. The primary source of the data presented is one Korean student’s personal narrative about his learning challenges and struggles in an intensive ESL program at a Canadian university. Findings of data call for a re-examination of hegemonic approaches that have become normative ways of framing, representing and describing L2 student writers and their learning challenges from a deficit view.
Intercultural Discourse Patterns in Writing Argumentative Texts
Authors: Margolin Bruria , Ezer Hanna
Published: February 2009

This study examines the quality of the writing of Jewish (L1) and Arab (L2) first-year student teachers at Hebrew-speaking colleges. The study seeks to understand the quality of argumentative writing of the student teachers at the beginning of their studies and to expose the discourse patterns that emerge from those argumentative texts. A code book serving as a coding analysis device was developed in order to reveal the following rhetorical text features: content, structure, syntax and style. Each global feature contained a number of specific measures. The findings indicate that the writing quality of first-year L1 students is significantly higher than that of first-year L2 students on all the specific writing measures examined. The texts of the Arab students were less coherent and lacked rhetorical structure and accepted grammatical forms, whereas those of the Jewish students were more coherent and self-explanatory. The study concludes that when Arab students write in Hebrew as a second language, the linguistic and rhetorical conventions of Arabic interfere with their Hebrew writing. The results demonstrate significant and interesting differences between Jewish native speakers (L1 students) and Arab non-native speakers (L2 students). While the texts of L1 students tend to display 'explicit coherence,' those of L2 students show 'implicit coherence.'
Discourse Features of Argumentative Essays Written by Chinese EFL Students
Authors: Miao Ruiqin , Lei Xiuyun
Published: February 2009

Studies on both second language discourse in general and Chinese EFL/ESL discourse in particular have reported mixed findings about the relationship between L1 and L2 writing. This study investigates the rhetorical features of argumentative essays written by Chinese college EFL students by analyzing paragraph and overall textual organization and development in 69 sample essays. The results show that the majority of the participants compose in a deductive pattern similar to what is typically employed by native English speaking writers. However, the way in which the Chinese EFL students develop their L2 written discourse lacks effectiveness and adequacy, in terms of the following features: the quality of the topic sentence (of paragraphs) and the introduction paragraph (of essays), the adequacy of supporting details, transitions between sentences and paragraphs, and the effectiveness of the ending (of essays). Furthermore, we explore the factors that may underlie the observed patterns. We conclude the paper by discussing the pedagogical implications of the findings and suggesting directions for future research.
Differences in Process and Process-Product Relations in L2 Writing
Authors: van Weijen Daphne , van den Bergh Huub , Rijlaarsdam Gert , Sanders Ted J.M.
Published: February 2009

This study examines whether writers vary how they write under influence of the changing task situation when writing in a second language (L2) and, if so, whether differences in the way they write are related to variations in text quality. Twenty first year students wrote four texts each in their L2 (English) under think-aloud conditions. The analysis focused on four cognitive activities: Reading the assignment and sources, Planning, Generating ideas and Formulating. Results indicate that, on average, the occurrence of each activity varies during the writing process. In addition, writers differ in the extent that they vary their process execution (i.e., the way they apply different activities) while writing. These differences, however, depend on the moment in the writing process, and on the activity being carried out. In general, writers’ behaviour is rather stable between tasks, at least at the start of the writing process. Finally, results indicate that the correlation between each activity and text quality varies during the writing process and also differs somewhat between tasks.
Global Simulation and Writing Self-Beliefs of Intermediate French Students
Authors: Mills Nicole , Péron Mélanie
Published: February 2009

Global simulation is described as “simultaneously an approach, a set of classroom techniques, and the conceptual framework for a syllabus” (Levine, 2004, p. 27). Students create a fictive yet culturally grounded world, assume the role of a self-developed character, and collaborate with fellow community members (Magnin, 1997). Despite its numerous cited advantages, there are no known empirical studies evaluating the influence of global simulation on language learners. This study evaluated how global simulation influenced the development of intermediate-French students’ writing self-beliefs and text quality. Significant differences were found in Intermediate French students’ writing self-efficacy, writing self-concept, writing anxiety, and text quality in organization, content, and creativity after participation in a global simulation curriculum. No significant differences were found in students’ self-efficacy for self-regulation, perceived value of writing, or text quality in grammar and expression. Implications for researchers and educators are discussed.
The Effect of Direct and Indirect Corrective Feedback on L2 Learners’ Written Accuracy
Authors: van Beuningen Catherine , de Jong N.H. , Kuiken Folkert
Published: February 2009

Among scholars there is disagreement on the benefits of corrective feedback on second language learners’ written output. While some researchers advocate the usefulness of corrective feedback, Truscott claims that all error correction is unnecessary, ineffective, and even harmful, in that it diverts time and energy away from more productive aspects of writing instruction.
Until now, research outcomes cannot settle this debate since only short-term effectiveness of corrective feedback could be demonstrated. Due to methodological shortcomings, results from studies that investigated long-term effects of error correction on accuracy improvement are inconclusive.

By trying to overcome some of these design related drawbacks (i.e. the lack of a proper control group and time-on task differences between treatment groups), the present study intends to make a contribution to the ongoing error correction debate. The effectiveness of direct and indirect corrective feedback was compared to the effect of two control treatments: a treatment that offered students an extra opportunity to practice their writing skills, and a treatment in which students self-corrected their errors without any available feedback. Results show that corrective feedback can be effective in improving students’ accuracy: while short-term effects were found for both direct and indirect corrective feedback, only direct feedback proved to have a significant long-term effect. Neither of the control treatments had a significant effect on students’ accuracy.
Documenting the Current State of the Healthy Municipalities, Cities and Communities Initiative in the Americas
Authors: Arteaga Erika , Rice Marilyn , Franceschini Maria Cristina
Published: February 2009

The objective of this study was to document the challenges, achievements, and lessons learned in municipalities where the Healthy Municipalities, Cities and Communities (HMC) strategy has been implemented in the Americas. A general survey was distributed through the HMC online network and through the Pan American Health Organization country offices. Municipalities answered questions regarding the planning, implementation, and evaluation phases of the strategy. Fifty-seven municipalities answered the survey. Ninety-three percent of the municipalities had signed a written agreement of political commitment to the HMC strategy. While 60% of the surveyed municipalities reported having a local health and well being situational analysis, 70% had an HMC Action Plan and only 58% had a follow-up and evaluation plan. The activities in which municipalities are engaged under the banner of the HMC strategy vary greatly in the Americas Region with varying degrees of success. Intersectorial collaboration and evaluation continues to be a challenge for the HMC initiative.
Multi-Media Campaign Exposure and Interpersonal Communication on Sexual Abstinence among Young People in Nigeria: A Propensity-Matched Study
Authors: Fatusi Adesegun O. , Wang Wenjuan , Anyanti Jennifer
Published: February 2009

A national multi-media campaign ( Zip-Up!) was initiated in Nigeria in 2004 to promote sexual abstinence among young people as part of comprehensive efforts to reduce sexually transmitted infection and unwanted pregnancy. This study assessed the effect of the campaign exposure on interpersonal communication about abstinence among a nationally representative sample of never-married young people (15–24 years). A propensity score matching technique was used to create a comparison group statistically equivalent to the group exposed to the campaign and assess the campaign effect. Of the 3,388 people sampled, 29.1% had been exposed to the campaign. Factors significantly associated with campaign exposure included age (OR = 1.08; 95% C.I. = 1.04–1.12), urban location (OR = 1.31; 95% C.I. = 1.04–1.66), and frequency of media use. Compared to the non-exposed group, campaign exposure was associated with a statistically significant adjusted increase of 10.9% in the proportion of young people who engaged in interpersonal communication about abstinence.