bluuebunny/crossref_metadata_2025 huggingface dataset:
Lack of Evidence for Oxidative Stress in Sporadic Amyotrophic Lateral Sclerosis Fibroblasts
Authors: Sala Gessica , Trombin Federica , Mattavelli Laura , Beretta Simone , Tremolizzo Lucio , Andreoni Simona , Calabrese Elena , Sanvito Lara , Ferrarese Carlo
Published: March 2008

Background: It is conceivable that an early therapeutic intervention in amyotrophic lateral sclerosis (ALS) would lead to better results in terms of disease progression for these patients. One possible strategy to increase the sensitivity of the diagnosis is represented by the use of biological parameters reflecting, for example, oxidative stress alterations associated with ALS. Such biomarkers would be valuable tools both for a better diagnostic evaluation and for studying the impact of therapeutic interventions on the disease course. A special category of experimental models is represented by peripheral cells obtained directly from patients (ex vivo). Objective: In this study, primary fibroblasts obtained from 10 sporadic ALS (SALS) patients and 10 healthy matched controls were used to investigate a panel of parameters related to the oxidative status. Methods: Reactive oxygen species production, protein carbonylation and nitration, susceptibility to hydrogen peroxide exposure, p38-mitogen-activated protein kinase activation and adenosine triphosphate intracellular content were evaluated. Results: No significant difference was observed in all investigated parameters between patient and control cells, and no correlation with the disease severity was found. Conclusion: Collectively, our data show no major alterations of the oxidative and bioenergetic status in SALS cultured fibroblasts, suggesting that these cells do not represent a useful model to study the oxidative dysfunction associated with SALS.
Nonsteroidal Anti-Inflammatory Drugs and Ectodomain Shedding of the Amyloid Precursor Protein
Authors: Leuchtenberger Stefanie , Maler Juan , Czirr Eva , Ness Julia , Lichtenthaler Stefan F. , Esselmann Hermann , Pietrzik Claus U. , Wiltfang Jens , Weggen Sascha
Published: March 2008

Background: Epidemiological studies have suggested that long-term use of nonsteroidal anti-inflammatory drugs (NSAIDs) is associated with a reduced incidence of Alzheimer’s disease (AD). Several mechanisms have been proposed to explain these findings including increased shedding of the soluble ectodomain of the amyloid precursor protein (sAPP), which functions as a neurotrophic and neuroprotective factor in vitroand in vivo. Objective: To clarify whether NSAIDs consistently stimulate sAPP secretion. Methods: 293-EBNA cells with stable overexpression of an APP-alkaline phosphatase fusion protein (APP-AP), SH-SY5Y and PC12 cells or primary telencephalic chicken neurons were treated with ibuprofen or indomethacin. APP shedding was then determined by measuring AP activity in conditioned media, Western blot analysis with antibodies against total sAPP or specific for sAPP-α, or in a pulse-chase paradigm. Results: AP activity in conditioned media was not increased after NSAID treatment of 293-EBNA cells whereas it was elevated by phorbol ester. Surprisingly, ibuprofen or indomethacin treatment of SH-SY5Y and PC12 cells expressing endogenous APP did not cause changes in sAPP or sAPP-α secretion or downregulation of cellular APP. These findings were further corroborated in primary chicken neuronal cultures. Conclusions: Using various experimental settings, we were unable to confirm sAPP or sAPP-α stimulation with the NSAIDs ibuprofen and indomethacin in transfected and nontransfected cells of neuronal and nonneuronal origin. Importantly, these findings seem to rule out chronic sAPP stimulation as an alternative mechanism of NSAID action in AD.
A Developmental Examination of Amygdala Response to Facial Expressions
Authors: Guyer Amanda E. , Monk Christopher S. , McClure-Tone Erin B. , Nelson Eric E. , Roberson-Nay Roxann , Adler Abby D. , Fromm Stephen J. , Leibenluft Ellen , Pine Daniel S. , Ernst Monique
Published: March 2008

Several lines of evidence implicate the amygdala in face-emotion processing, particularly for fearful facial expressions. Related findings suggest that face-emotion processing engages the amygdala within an interconnected circuitry that can be studied using a functional-connectivity approach. Past work also underscores important functional changes in the amygdala during development. Taken together, prior research on amygdala function and development reveals a need for more work examining developmental changes in the amygdala's response to fearful faces and in amygdala functional connectivity during face processing. The present study used event-related functional magnetic resonance imaging to compare 31 adolescents (9–17 years old) and 30 adults (21–40 years old) on activation to fearful faces in the amygdala and other regions implicated in face processing. Moreover, these data were used to compare patterns of amygdala functional connectivity in adolescents and adults. During passive viewing, adolescents demonstrated greater amygdala and fusiform activation to fearful faces than did adults. Functional connectivity analysis revealed stronger connectivity between the amygdala and the hippocampus in adults than in adolescents. Within each group, variability in age did not correlate with amygdala response, and sex-related developmental differences in amygdala response were not found. Eye movement data collected outside of the magnetic resonance imaging scanner using the same task suggested that developmental differences in amygdala activation were not attributable to differences in eye-gaze patterns. Amygdala hyperactivation in response to fearful faces may explain increased vulnerability to affective disorders in adolescence; stronger amygdala-hippocampus connectivity in adults than adolescents may reflect maturation in learning or habituation to facial expressions.
Dissociation between Decoding and Reasoning about Mental States in Patients with Theory of Mind Reasoning Impairments
Authors: Njomboro Progress , Deb Shoumitro , Humphreys Glyn W.
Published: March 2008

Theory of mind (ToM) reasoning may involve a multiplicity of processes, including an initial stage, where cues relevant for social processes are detected and decoded, and a mentalizing stage, where the decoded information is used to reason about mental states. Here we report that the processing of lower-order facial cues relevant to social judgments can be relatively spared in patients with impaired ToM reasoning. We discuss the implications for understanding the mechanisms underlying social judgments in brain-lesioned patients.
Number Forms in the Brain
Authors: Tang Joey , Ward Jamie , Butterworth Brian
Published: March 2008

Mental images of number lines, Galton's “number forms” (NF), are a useful way of investigating the relation between number and space. Here we report the first neuroimaging study of number-form synesthesia, investigating 10 synesthetes with NFs going from left to right compared with matched controls. Neuroimaging with functional magnetic resonance imaging revealed no difference in brain activation during a task focused on number magnitude but, in a comparable task on number order, synesthetes showed additional activations in the left and right posterior intraparietal sulci, suggesting that NFs are essentially ordinal in nature. Our results suggest that there are separate but partially overlapping neural circuits for the processing of ordinal and cardinal numbers, irrespective of the presence of an NF, but a core region in the anterior intraparietal sulcus representing (cardinal) number meaning appears to be activated autonomously, irrespective of task. This article provides an important extension beyond previous studies that have focused on word-color or grapheme-color synesthesia.
Grasp Recognition for Uncalibrated Data Gloves: A Machine Learning Approach
Authors: Heumer Guido , Amor Heni Ben , Jung Bernhard
Published: March 2008

This paper presents a comparison of various machine learning methods applied to the problem of recognizing grasp types involved in object manipulations performed with a data glove. Conventional wisdom holds that data gloves need calibration in order to obtain accurate results. However, calibration is a time-consuming process, inherently user-specific, and its results are often not perfect. In contrast, the present study aims at evaluating recognition methods that do not require prior calibration of the data glove. Instead, raw sensor readings are used as input features that are directly mapped to different categories of hand shapes. An experiment was carried out in which test persons wearing a data glove had to grasp physical objects of different shapes corresponding to the various grasp types of the Schlesinger taxonomy. The collected data was comprehensively analyzed using numerous classification techniques provided in an open-source machine learning toolbox. Evaluated machine learning methods are composed of (a) 38 classifiers including different types of function learners, decision trees, rule-based learners, Bayes nets, and lazy learners; (b) data preprocessing using principal component analysis (PCA) with varying degrees of dimensionality reduction; and (c) five meta-learning algorithms under various configurations where selection of suitable base classifier combinations was informed by the results of the foregoing classifier evaluation. Classification performance was analyzed in six different settings, representing various application scenarios with differing generalization demands. The results of this work are twofold: (1) We show that a reasonably good to highly reliable recognition of grasp types can be achieved—depending on whether or not the glove user is among those training the classifier—even with uncalibrated data gloves. (2) We identify the best performing classification methods for the recognition of various grasp types. To conclude, cumbersome calibration processes before productive usage of data gloves can be spared in many situations.
Consistent Left-Right Reversals for Visual Path Integration in Virtual Reality: More than a Failure to Update One's Heading?
Authors: Riecke Bernhard E.
Published: March 2008

Even in state-of-the-art virtual reality (VR) setups, participants often feel lost when navigating through virtual environments. In VR applications and psychological experiments, such disorientation is often compensated for by extensive training. Here, two experimental series investigated participants' sense of direction by means of a rapid point-to-origin paradigm without any performance feedback or training. This paradigm allowed us to study participants' intuitive spatial orientation in VR while minimizing the influence of higher cognitive abilities and compensatory strategies. After visually displayed passive excursions along one- or two-segment trajectories, participants were asked to point back to the origin of locomotion “as accurately and quickly as possible.” Despite using an immersive, high-quality video projection with a 84° × 63° field of view, participants' overall performance was rather poor. Moreover, about 40% of the participants exhibited striking qualitative errors, namely left-right reversals—despite not misinterpreting the visually simulated turning direction. Even when turning angles were announced in advance to obviate encoding errors due to misperceived turning angles, many participants still produced surprisingly large systematic and random errors, and perceived task difficulty and response times were unexpectedly high. Careful analysis suggests that some, but not all, of the left-right inversions can be explained by a failure to update visually displayed heading changes. Taken together, this study shows that even an immersive, high-quality video projection system is not necessarily sufficient for enabling natural and intuitive spatial orientation or automatic spatial updating in VR, even when advance information about turning angles was provided. We posit that investigating qualitative errors for basic spatial orientation tasks using, for example, rapid point-to-origin paradigms can be a powerful tool for evaluating and improving the effectiveness of VR setups in terms of enabling natural and unencumbered spatial orientation and performance. We provide some guidelines for VR system designers.
Maintenance of genetic variation in automictic root-knot nematodes
Authors: Pijnacker Laas , van der Beek (Hans)
Published: March 2008

Differences in amplified fragment length polymorphisms (AFLP) between isolates and between mono-female lines of facultative automictic Meloidogyne hapla race A and obligate apomictic M. incognita were determined to test the hypothesis that inverted meiosis occurs. DNA of the parthenogenetic nematode lines were extracted from juveniles, which had been propagated for two generations, allowing males in M. hapla lines to be formed and fertilisation to take place. Based on AFLP analysis, the genetic distance between mono-female lines of M. incognita appeared to be almost nil. By contrast, the genetic distance between isolates and between mono-female lines after seven generations of parthenogenesis of M. hapla was larger. The genetic distance between two mono-female lines of M. hapla, after one generation of parthenogenesis and originating from one line with six generations of parthenogenesis, was larger than the distance between M. incognita lines and the smallest distance between M. hapla lines. The numbers of DNA fragments appeared to be equally variable between lines within a single M. hapla isolate as between various isolates of M. hapla. This maintenance of genetic variation in M. hapla is likely to be caused by the combination of post-reduction in an inverted meiosis, due to chromosomes with diffuse centromeres, and the fusion of the haploid products of the second meiotic division.
Trichodoridae (Nematoda: Triplonchida) from the Tara National Park, Serbia, and proposal of Trichodorus pseudobursatus n. sp.
Authors: Decraemer Wilfrida , de la Peña Eduardo , Radivojević Milan
Published: March 2008

A survey for plant-root parasites in Tara National Park, Serbia, revealed the widespread occurrence of Trichodoridae, present in nearly one-third of the samples. Several species appeared to belong to the Trichodorus aequalis species complex sensu Loof (1973). The taxonomic value of the observed variations in diagnostic features within this species complex is discussed. A new species Trichodorus pseudobursatus n. sp. is described. It is characterised by males with a nearly straight habitus, two ventromedian cervical papillae anterior to the secretory-excretory pore, medium-sized and mostly straight spicules with wider manubrium continuous with the blade; blade with a smooth narrower part with a few bristles at mid-spicule, followed by a wider striated posterior part devoid of bristles. Females are characterised by a large, well developed pear-shaped vagina with medium-sized, rounded triangular and well separated vaginal sclerotised pieces in lateral optical view. In addition to the diagnostic morphological features, differentiation of the new species from other Serbian morphotypes of the Trichodorus sparsus species complex was supported by canonical discriminant analyses (CDA). Additional information is provided for T. sparsus and three T. aff. sparsus morphotypes from Serbia. The discovery of the genus Trichodorus in Serbia represents a new geographical record.
Heterorhabditis safricana n. sp. (Rhabditida: Heterorhabditidae), a new entomopathogenic nematode from South Africa
Authors: Tiedt Louwrence , Nguyen Khuong , de Waal Jeanne , Malan Antoinette
Published: March 2008

During a survey for entomopathogenic nematodes in the Western Cape Province of South Africa, a new species in the genus Heterorhabditis was collected from a peach orchard. The nematode was trapped by the insect-baiting technique using last instar larvae of Galleria mellonella. The infective juvenile of the new species differs from the morphologically closest species, H. marelatus, in shorter body length 600 (550-676) vs 685 (588-700) μm and the shorter tail of 93 (86-108) vs 107 (99-117) μm. It differs from all other species in the vulva pattern of hermaphroditic female. The genital papillae of the male H. safricana n. sp. are typical for species in the megidis-group (three papillae in terminal group). The average length of the gubernaculum is longer than that of all other species (24 vs 19-23 μm) and the gubernaculum length as a percentage of spicule length (53.9) is less than that of H. mexicana (56), similar to that of H. floridensis (53.8), but larger than that of all others (51 or less). For molecular characterisation, the species closest to H. safricana n. sp. is H. marelatus. The length of the ITS rDNA sequence of the new species is characterised by 995 base pairs, identical to that of H. marelatus, but differs from this species by 25 aligned positions, seven of which are unambiguous autapomorphies. Phylogenetic trees show further evidence of a separate species status for H. safricana n. sp.
Effect of Meloidogyne hapla on multi-purpose use of oilseed radish (Raphanus sativus)
Authors: Mennan Sevilhan , Ngouajio Mathieu , Melakeberhan Haddish , Dudek Thomas
Published: March 2008

Oilseed radish (OSR; Raphanus sativus), which can be used as a trap, cover or biofumigant when incorporated as a green manure crop, has potential for managing soil-borne biotic factors such as Meloidogyne hapla. However, exploiting the multi-purpose traits of OSR requires careful understanding of the biology of M. hapla and the prevailing soil conditions. When an OSR Line 'RO4S-PSOSR', and cv. Diakon grown in 300 cm3 of sandy, loamy sand or muck soils were inoculated with 3000 eggs of M. hapla populations (collected from the three soil types) and maintained for approximately 500 degree days (DD, base 10°C), all nematodes completed their life cycle in both hosts, with significantly more nematodes infecting OSR plants in the sandy soil. When cvs Diakon and Rutgers tomato (standard susceptible species) were grown under the same conditions with an inoculum of 2000 eggs per pot, infection was greatest in the sandy soils. Oilseed radish shoot growth was significantly lower in the sandy soil compared with muck or loamy sand soils. While the effect of soil type on OSR growth and M. hapla population densities is to be expected, the nematodes' completion of a life cycle at about 450-500 DD suggests that OSR hosts like cv. Diakon may be best used as a trap crop and plants should be terminated before the nematode completes a life cycle.
Atypical Thermodynamic Profiles in Hurricanes
Authors: Barnes Gary M.
Published: March 2008

The global positioning system dropwindsondes deployed in Hurricane Bonnie on 26 August 1998 with supporting deployments in Hurricanes Mitch (1998) and Humberto (2001) are used to identify three unusual thermodynamic structures in the lower-cloud and subcloud layers. Two of these structures impact the energy content of the inflow and therefore the intensity of the hurricane. First, positive lapse rates of equivalent potential temperature are found near the top of the inflow. These layers insulate the inflow from the negative impacts of entrainment mixing and promote rapid energy increases, especially near the eyewall. The second structure is a rapid decrease of equivalent potential temperature adjacent to the sea surface. This is essentially a prominent surface layer that owes its existence to both higher moisture content and a superadiabatic lapse rate. The steep lapse rate most often occurs under and near the eyewall where wind speeds at the surface exceed hurricane force. The author speculates that water loading from spray increases the residence time of air parcels in the surface layer, contributing to the creation of this structure. The third feature is a moist absolutely unstable layer previously identified by Bryan and Fritsch for the midlatitudes. These layers are found adjacent to the eyewall, in rainbands, and in the hub cloud within the eye and are evidence of mesoscale or vortex-scale convergence and the very modest instabilities often found in the core of a hurricane.
Tests of an Ensemble Kalman Filter for Mesoscale and Regional-Scale Data Assimilation. Part III: Comparison with 3DVAR in a Real-Data Case Study
Authors: Meng Zhiyong , Zhang Fuqing
Published: March 2008

The feasibility of using an ensemble Kalman filter (EnKF) for mesoscale and regional-scale data assimilation has been demonstrated in the authors’ recent studies via observing system simulation experiments (OSSEs) both under a perfect-model assumption and in the presence of significant model error. The current study extends the EnKF to assimilate real-data observations for a warm-season mesoscale convective vortex (MCV) event on 10–12 June 2003. Direct comparison between the EnKF and a three-dimensional variational data assimilation (3DVAR) system, both implemented in the Weather Research and Forecasting model (WRF), is carried out. It is found that the EnKF consistently performs better than the 3DVAR method by assimilating either individual or multiple data sources (i.e., sounding, surface, and wind profiler) for this MCV event. Background error covariance plays an important role in the performance of both the EnKF and the 3DVAR system. Proper covariance inflation and the use of different combinations of physical parameterization schemes in different ensemble members (the so-called multischeme ensemble) can significantly improve the EnKF performance. The 3DVAR system can benefit substantially from using short-term ensembles to improve the prior estimate (with the ensemble mean). Noticeable improvement is also achieved by including some flow dependence in the background error covariance of 3DVAR.
Mountain Torque Events at the Tibetan Plateau
Authors: Egger Joseph , Hoinka Klaus-Peter
Published: March 2008

The interaction of large-scale wave systems with the Tibetan Plateau (TP) is investigated by regressing pressure, potential temperature, winds, precipitation, and selected fluxes in winter onto the three components Toi of this massif’s mountain torque on the basis of the 40-yr ECMWF reanalysis (ERA-40) data. Events with respect to the equatorial “Greenwich” axis of the global angular momentum exhibit by far the largest torques (To1,), which essentially represent north–south pressure differences across the TP. The axial torque To3 peaks when the surface pressure is high at the eastern slope of the TP. The torque To2 with respect to the 90°E axis is closely related to To3 with To2 ∼ −To3. The maximum (minimum) of To1 tends to occur about 1 day earlier than the minimum (maximum) of To2. All torque events are initiated by equivalent barotropic perturbations moving eastward along the northern rim of the TP. In general, the initial depression, for example, forms a southward-protruding extension at the eastern slope of the TP and a new high grows near Japan. Later, the perturbation near Japan moves eastward in To2 events but extends northward in To1 events. These flow developments cannot be explained by theories of topographic instability. The observed vertical motion at the lee slope is at best partly consistent with theories of linear quasigeostrophic wave motion along mountain slopes. These findings lead the authors to test the eventual usefulness of linear theories by fitting the linear terms of a novel statistical equation for the potential temperature θ to the observed changes of θ and the torque to the observations. This test indicates that the evolving regression patterns of θ can be explained by linear terms at least in specific domains. In turn, pressure tendency regressions at a selected level can be calculated on the basis of the linear θ tendencies above that level. The formation of the lee trough appears to be mainly caused by horizontal warm-air advection along the slopes, but changes of the potential temperature above the height of the TP also contribute significantly to the pressure changes in the lee. Cold-air advection aloft strengthens the Japan high. “Turbulent” transports appear to be mainly responsible for the decay of the perturbations but data accuracy problems impede the analysis. In particular, the noisiness of the vertical motion fields affects the skill of the linear calculations.
A Numerical Study of the Track Deflection of Supertyphoon Haitang (2005) Prior to Its Landfall in Taiwan
Authors: Jian Guo-Ji , Wu Chun-Chieh
Published: March 2008

A series of numerical simulations are conducted using the advanced research version of the Weather Research and Forecasting model with a 4-km fine mesh to examine the physical processes responsible for the significant track deflection and looping motion before the landfall of Supertyphoon Haitang (2005) in Taiwan, which poses a unique scientific and forecasting issue. In the control experiment, a low-level northerly jet induced by the channeling effect forms in the western quadrant of the approaching storm, where the inner-core circulation is constrained by the presence of Taiwan’s terrain. Because of the channeling effect, the strongest winds of the storm are shifted to the western portion of the eyewall. The northerly advection flow (averaged asymmetric winds within 100-km radius) results in a sharp southward turn of the westward-moving storm. The time series of the advection flow shows that the advection wind vectors rotate cyclonically in time and well match the motion of the simulated vortex during the looping process. A sensitivity study of lowering the Taiwan terrain elevations to 70% or 40% of those in the control experiment reduces the southward track deflection and loop amplitude. The experiment with the reduced elevation to 10% of the control experiment does not show a looping track and thus demonstrates the key role of the terrain-induced channeling effect. Experiments applying different values of the structure parameter α illustrate that increasing the strength, size, and translation speed of the initial storm results in a smaller interaction with Taiwan’s terrain and a smaller average steering flow caused by the asymmetric circulation, which leads to a proportionally smaller southward track deflection without making a loop.
Tracer Conservation for Three-Dimensional, Finite-Element, Free-Surface, Ocean Modeling on Moving Prismatic Meshes
Authors: White Laurent , Legat Vincent , Deleersnijder Eric
Published: March 2008

Large-scale free-surface ocean models designed to run over climatic time scales are required to globally conserve the volume and any tracer up to machine precision. In addition, local consistency is critical and requires that the discrete tracer equation preserve constants in a closed domain and if there is no tracer source or sink. Local consistency, together with monotonicity, will ensure that no spurious tracer extrema occur. A three-dimensional, finite-element, shallow-water model is presented. The mesh is unstructured in the horizontal, extruded in the third dimension, and made up of multiple layers of prisms. In addition, the mesh is allowed to move in the vertical and adapts itself to the free-surface motions. It is shown that achieving consistency requires a discrete compatibility between the tracer and continuity equations. In addition, to ensure global tracer conservation in a consistent way, a discrete compatibility between the tracer, continuity, and free-surface elevation equations must be fulfilled. It is suggested that this compatibility constraint, together with the use of a numerically stable scheme, severely restricts the choice of usable finite-element spatial discretizations. A consistent and conservative time-stepping algorithm is described for which a unique time step is used. It is suggested that future research is needed in order to design a consistent and conservative split-explicit algorithm. Some illustrative test cases are presented in which the method is shown to satisfy all conservation properties. A few experiments in which consistency breaks down are carried out, and the consequences of this breakdown process are investigated.
Impact Study of AMSR-E Radiances in the NCEP Global Data Assimilation System
Authors: Kazumori Masahiro , Liu Quanhua , Treadon Russ , Derber John C.
Published: March 2008

The impact of radiance observations from the Advanced Microwave Scanning Radiometer for Earth Observing System (AMSR-E) was investigated in the National Centers for Environmental Prediction (NCEP) Global Data Assimilation System (GDAS). The GDAS used NCEP’s Gridpoint Statistical Interpolation (GSI) analysis system and the operational NCEP global forecast model. To improve the performance of AMSR-E low-frequency channels, a new microwave ocean emissivity model and its adjoint with respect to the surface wind speed and temperature were developed and incorporated into the assimilation system. The most significant impacts of AMSR-E radiances on the analysis were an increase in temperature of about 0.2 K at 850 hPa at the higher latitudes and a decrease in humidity of about 0.1 g kg−1 at 850 hPa over the ocean when the new emissivity model was used. There was no significant difference in the mean 6-h rainfall in the assimilation cycle. The forecasts made from the assimilation that included the AMSR-E data showed small improvements in the anomaly correlation of geopotential height at 1000 and 500 hPa in the Southern Hemisphere and reductions in the root-mean-square error (RMSE) for 500-hPa geopotential height in the extratropics of both hemispheres. Use of the new emissivity model resulted in improved RMSE for temperature forecasts from 1000 to 100 hPa in the extratropics of both hemispheres. The assimilation of AMSR-E radiances data using the emissivity model improved the track forecast for Hurricane Katrina in the 26 August 2005 case, whereas the assimilation using the NCEP operational emissivity model, FAST Emissivity Model, version 1 (FASTEM-1), degraded it.
Aircraft Observations of a Coastally Trapped Wind Reversal off the California Coast
Authors: Parish Thomas R. , Rahn David A. , Leon David
Published: March 2008

The summertime marine atmospheric boundary layer off the California coast is normally characterized by northerly winds associated with the Pacific high. This pattern is occasionally disturbed by episodes of southerly winds and a finger of fog or low stratus adjacent to the coastline extending approximately 100 km offshore. These events propagate northward along the coast with speeds between 5 and 12 m s−1 and have a life span of several days. These occurrences have been referred to as coastally trapped wind reversals (CTWRs), coastally trapped disturbances, or southerly surges. The CTWR event of 22–25 June 2006 was explored by the University of Wyoming King Air research aircraft to document the physical characteristics of the wind reversal in an attempt to infer the forcing mechanisms responsible for the propagation. Two flights from 23 June are presented that are representative of the CTWR during its mature stage. Sawtooth maneuvers depict the CTWR vertical structure, and isobaric legs directly measure the horizontal pressure gradient force (PGF). Observations showed a thickening of the CTWR layer in an alongshore direction to the south. The inversion layer varies throughout the day with the final sawtooth leg depicting clear dynamic destabilization within the inversion layer. A PGF is present at the head of the CTWR that is directed northward. No significant PGF was detected in the cross-shore direction, suggesting that for this case there is little variation in the depth of the marine boundary layer normal to the coast.
Climate Change Impact on Rice Insurance Payouts in Japan
Authors: Iizumi Toshichika , Yokozawa Masayuki , Hayashi Yousay , Kimura Fujio
Published: March 2008

The authors constructed the framework for a preliminary assessment of climate change impact on the rice insurance payout in Japan. The framework consisted of various models ranging from climate projection downscaling, rice yield estimation, yield loss assessment, and rice insurance payout estimation. In this study, a simulation was conducted based on the dynamically downscaled regional climate projection with a lateral boundary condition given by the global climate projection of the Meteorological Research Institute Coupled General Circulation Model, version 2 (MRI CGCM2), under the A2 scenario of the Special Report on Emission Scenarios (SRES). Results indicated that rice yield in the 2070s will decrease slightly in central and western Japan and increase in northern Japan. The increase in yield was derived from a significant reduction in yield loss caused by cool-summer damage; on the other hand, the decrease in yield was caused by the increase in yield loss caused by heat stress and the shortening of the growth period induced by the temperature rise. The increase in the atmospheric CO2 concentration resulted in an increase in paddy rice biomass because of the fertilization effect; however, the increase in biomass was not enhanced much as a result of shortening of the growth period if early planting was not considered as an adaptation practice. Reflecting such changes in yield, the rice insurance payout significantly decreased in northern Japan but only slightly increased in the areas of central and western Japan. In total, the 9-yr mean payout in Japan in the 2070s decreased to 120.2 billion yen; the value corresponded to 87% of the payout averaged over 9 yr in the 1990s (1991–99).
Changing Expendable Bathythermograph Fall Rates and Their Impact on Estimates of Thermosteric Sea Level Rise
Authors: Wijffels Susan E. , Willis Josh , Domingues Catia M. , Barker Paul , White Neil J. , Gronell Ann , Ridgway Ken , Church John A.
Published: March 2008

A time-varying warm bias in the global XBT data archive is demonstrated to be largely due to changes in the fall rate of XBT probes likely associated with small manufacturing changes at the factory. Deep-reaching XBTs have a different fall rate history than shallow XBTs. Fall rates were fastest in the early 1970s, reached a minimum between 1975 and 1985, reached another maximum in the late 1980s and early 1990s, and have been declining since. Field XBT/CTD intercomparisons and a pseudoprofile technique based on satellite altimetry largely confirm this time history. A global correction is presented and applied to estimates of the thermosteric component of sea level rise. The XBT fall rate minimum from 1975 to 1985 appears as a 10-yr “warm period” in the global ocean in thermosteric sea level and heat content estimates using uncorrected data. Upon correction, the thermosteric sea level curve has reduced decadal variability and a larger, steadier long-term trend.
Application of an Adiabatic WRF Adjoint to the Investigation of the May 2004 McMurdo, Antarctica, Severe Wind Event
Authors: Xiao Qingnong , Kuo Ying-Hwa , Ma Zaizhong , Huang Wei , Huang Xiang-Yu , Zhang Xiaoyan , Barker Dale M. , Michalakes John , Dudhia Jimy
Published: March 2008

The tangent linear and adjoint of an adiabatic version of the Weather Research and Forecasting (WRF) Model with its Advanced Research WRF (ARW) dynamic core have been developed. The source-to-source automatic differentiation tool [i.e., the Transformation of Algorithm (TAF) in FORTRAN] was used in the development. Tangent linear and adjoint checks of the developed adiabatic WRF adjoint modeling system (WAMS) were conducted, and all necessary correctness verification procedures were passed. As the first application, the adiabatic WAMS was used to study the adjoint sensitivity of a severe windstorm in Antarctica. Linearity tests indicated that an adjoint-based sensitivity study with the Antarctic Mesoscale Prediction System (AMPS) 90-km domain configuration for the windstorm is valid up to 24 h. The adjoint-based sensitivity calculation with adiabatic WAMS identified sensitive regions for the improvement of the 24-h forecast of the windstorm. It is indicated that the windstorm forecast largely relies on the model initial conditions in the area from the south part of the Trans-Antarctic Mountains to West Antarctica and between the Ross Ice Shelf and the South Pole. Based on the sensitivity analysis, the southerly or southeasterly wind at lower levels in the sensitivity region should be larger, the cyclone should be stronger, and the atmospheric stratification should be more stable over the north slope of the Trans-Antarctic Mountain to the Ross Ice Shelf, than the AMPS analyses. By constructing pseudo-observations in the sensitivity region using the gradient information of forecast windstorm intensity around McMurdo, the model initial conditions are revised with the WRF three-dimensional variational data assimilation, which leads to significant improvement in the prediction of the windstorm. An adjoint sensitivity study is an efficient way to identify sensitivity regions in order to collect more observations in the region for better forecasts in a specific aspect of interest.
Communicating Uncertainty in Weather Forecasts: A Survey of the U.S. Public
Authors: Morss Rebecca E. , Demuth Julie L. , Lazo Jeffrey K.
Published: March 2008

Weather forecasts are inherently uncertain, and meteorologists have information about weather forecast uncertainty that is not readily available to most forecast users. Yet effectively communicating forecast uncertainty to nonmeteorologists remains challenging. Improving forecast uncertainty communication requires research-based knowledge that can inform decisions on what uncertainty information to communicate, when, and how to do so. To help build such knowledge, this article explores the public’s perspectives on everyday weather forecast uncertainty and uncertainty information using results from a nationwide survey. By contributing to the fundamental understanding of laypeople’s views on forecast uncertainty, the findings can inform both uncertainty communication and related research.

The article uses empirical data from a nationwide survey of the U.S. public to investigate beliefs commonly held among meteorologists and to explore new topics. The results show that when given a deterministic temperature forecast, most respondents expected the temperature to fall within a range around the predicted value. In other words, most people inferred uncertainty into the deterministic forecast. People’s preferences for deterministic versus nondeterministic forecasts were examined in two situations; in both, a significant majority of respondents liked weather forecasts that expressed uncertainty, and many preferred such forecasts to single-valued forecasts. The article also discusses people’s confidence in different types of forecasts, their interpretations of the probability of precipitation forecasts, and their preferences for how forecast uncertainty is conveyed. Further empirical research is needed to study the article’s findings in other contexts and to continue exploring perception, interpretation, communication, and use of weather forecast uncertainty.
Water, Equity and Development
Authors: Phansalkar Sanjiv J.
Published: March 2008

This article attempts to synthesize the research presented at the Fifth Annual Partners Meet of the International Water Management Institute (IWMI)– Tata Programme held in Anand, Gujarat, in March 2006. It specifically focuses on the prevalence and nature of inequities in water distribution. It shows that institutions in force create inequity in access to water in all the regions of the country; the landless and the dalits usually facing the brunt of the inequities.The inequities are more pronounced when water is considered as an input for economic activities such as agriculture. Geo-genic factors such as contamination of groundwater are compounded with inequities to severely impact the health and well-being of the poor and the weaker segments of the society. Finally, imbalance of social power allows industry to exploit water sources, producing inequities in use of water across sectors.
Impacts of Groundwater Contamination with Fluoride and Arsenic
Authors: Indu Rajnarayan , Krishnan Sunderrajan , Shah Tushaar
Published: March 2008

In India, high fluoride concentration in groundwater (greater than 1 mg/l) is widespread in the arid to semi-arid western states of Rajasthan and Gujarat and in the southern states of Andhra Pradesh, Karnataka and Tamil Nadu. A field research study conducted at six areas severely affected by fluorosis shows that affordability of safer drinking water is related to higher income level, and that the severity of fluorosis affliction is higher for lower income levels. The cost incurred on medicines and loss of wages is a significant proportion of the earnings and has a general debilitating impact on the affected families. As compared with fluorosis, the skin afflictions of arsenicosis carry greater social stigma and patients incur higher costs. In Nadia district of West Bengal, the impacts of arsenic contamination are more severe with increasing age. Cumulatively, over the entire afflicted population, both fluoride and arsenic contamination have a high cost on society and addressing the problem would require more attention from government agencies and society apart from individual awareness.
Poor and their Livestock
Authors: Phansalkar Sanjiv J.
Published: March 2008

Based on field work carried out in 13 locations across the country, this article aims to characterize the current situation regarding how the poor manage the water requirement for their livestock. It is found that each day on an average the poor require 13 litres of drinking water for animals and about 40 litres for washing and cleaning them. The poor households in western, central and southern parts of the country have a more difficult time managing water requirements of their livestock and in times of water scarcity these difficulties become very severe. They rely on water sources in the public domain and often use the sources created for human drinking end use. Markets for water for the poor appear to exist only in those pockets where livestock rearing has assumed commercial nature. Elsewhere, social norms such as the Jeevdaya tradition of Gujarat and Rajasthan, and reliance on water sources owned by the big farmers, are more the norm. Considering the importance of livestock to the household economy of the poor, greater public attention to this issue is called for.
Irrigation Service Delivery in Canal Systems
Authors: Choudhury Nirmalya
Published: March 2008

Irrigation has always been a priority for India, for which bulk of expenditure has been spent on creation of major and medium irrigation projects. To provide superior irrigation service to the farmers, it becomes important to know at the outset how the farmers perceive the current irrigation service delivery system. For this, we did a study. Our results show that only 69 per cent reported canal irrigation as the dominant source of irrigation. Only 56 per cent of the total irrigation needs of an individual farmer come from the canals. Accountability of the service providers towards the farmers is currently lacking and needs major attention in the future. Quality of the service delivery varied across different sections of the command of a system, with the tail reaches receiving the worst service, effectively shrinking the actual command.
Automatic nanohandling station inside a scanning electron microscope
Authors: Fatikow S , Wich T , Sievers T , Jähnisch M , Eichhorn V , Mircea J , Hülsen H , Stolle Ch
Published: March 2008

Current research work on the development of automated nanohandling systems in a scanning electron microscope (SEM) is presented. Two experimental set-ups are shown in which nanohandling robots operate in the vacuum chamber of an SEM. A client—server control system that can integrate various microrobots and sensors has been developed and evaluated by automatic handling of TEM (transmission electron microscope) lamellae by two nanorobots. The robots are controlled in a closed-loop way by using images from several CCD (charge coupled device) cameras and from the SEM. Algorithms for real-time processing of noisy SEM images have been implemented and tested. The experiment on automatic handling of TEM lamellae inside an SEM is described. The other set-up contains a nanohandling robot using the probe of an atomic force microscope (AFM) as end-effector. The manipulation of individual multiwall carbon nanotubes (MWNTs) and the characterization of nanofilms by nanoindentation are the applications being investigated. The experimental set-up includes a nanopositioning piezo stage with three degrees of freedom (DoF) and a three-axis nanomanipulator. Piezoresistive AFM probes are applied as end-effectors. In this way the acting forces can be detected, allowing force feedback for the station's control system. First investigations have been carried out by bending MWNTs and calculating their elastic modulus.
Laser milling: Pulse duration effects on surface integrity
Authors: Petkov P V , Dimov S S , Minev R M , Pham D T
Published: March 2008

Laser milling of engineering materials is a viable alternative to conventional methods for machining complex microcomponents. The laser source employed to perform such microstructuring has a direct impact on achievable surface integrity. At the same time, the trade-offs between high removal rates and the resulting surface integrity should be taken into account when selecting the most appropriate ablation regime for performing laser milling. In this paper the effects of pulse duration on surface quality and material microstructure are investigated when ablating a material commonly used for manufacturing microtooling inserts. For both micro- and nanosecond laser regimes, it was estimated that the heat-affected zone on the processed surface is within 50 μm. When performing ultra-short pulsed laser ablation, the effects of heat transfer are not as evident as they are after processing with longer laser pulse durations. Although some heat is dissipated into the bulk when working in pico- and femtosecond regimes it is not sufficient to trigger significant structural changes.
Microforming of titanium — forming behaviour at elevated temperature
Authors: Eichenhüller B , Engel U
Published: March 2008

Titanium is applied in a wide range of technical applications, especially when high strength in combination with light weight or corrosion resistance is demanded. Titanium is also a popular material for implants in the field of medical technology due to its specific properties like the superb biocompatibility, the elastic behaviour matching that of the human bone, the radiological transparency, and the galvanic neutrality. For the production of microparts, e.g. small-sized implants, manufacturing methods with high accuracy and close tolerances are necessary. If forming processes are used to manufacture the miniaturized medical components, then the size effects occurring with miniaturization have to be considered. The size effects are, among others, responsible for an increased scatter of characteristic process outcomes and a reduced accuracy, thereby reducing the process stability. The limited formability of titanium and titanium alloys at room temperature is also a drawback of forming microparts made of titanium. The main objective of the present study is to investigate the forming behaviour of titanium at microscale and improve its formability by means of forming at elevated temperature.
A Model of Housing in the Presence of Adjustment Costs: A Structural Interpretation of Habit Persistence
Authors: Flavin Marjorie , Nakagawa Shinobu
Published: March 2008

The paper provides a model of household consumption and portfolio allocation which incorporates housing as both a consumption good and a component of wealth. Household utility depends, possibly nonseparably, on two goods: nondurable consumption, which is costlessly adjustable, and housing, which is subject to a nonconvex adjustment cost. Households face housing price risk in the sense that the relative price of housing varies over time, and can invest in a wide variety of financial assets in addition to housing. This single, reasonably tractable, model generates testable implications for portfolio allocation, risk aversion, asset pricing, and the dynamics of nondurable consumption. (JEL D14, G11, R21)