bluuebunny/crossref_metadata_2025 huggingface dataset:
Influence of dietary fish oil supplementation on humoral immune response and some selected biochemical parameters of broiler chickens
Authors: Hosseini-Mansoub Navid , Bahrami Yadollah
Published: September 2011

Influence of dietary fish oil supplementation on humoral immune response and some selected biochemical parameters of broiler chickens

The objective of this experiment was to evaluate the influence of fish oil (FO) supplementation in the diet of broiler chickens on the humoral immune response as well as some blood parameters. Two hundred and sixteen one day old broiler chickens were divided into four dietary groups 0, 1, 2, or 4% FO with 3 replicates of 18 birds. Four chicks randomly selected and marked from each replicate were immunized intramuscularly with 0.2 ml of 5% sheep red blood cells (SRBC) as a non-infectious antigen, at the ages of 15 and 35 days and blood samples were taken 7 days after each immunization. The highest BW was observed in the 2% FO dietary group (T3), followed by T2 (P<0.01). The serum cholesterol and triglyceride levels significantly decreased in the FO groups at the age of 42 days (P<0.01). In addition, the inclusion of FO in broiler diets significantly increased the blood glucose (G) level and decreased the total protein (TP), albumin (A) and globulin (GL) concentrations. Fish oil-treated birds had significantly more serum antibody (predominantly immunoglobulin M, IgM) to SRBC than the control group. The highest response to primary and secondary injections of SRBC after 7 days, were detected for group 4 (4% FO), followed by 2% FO group (P<0.05). The results indicate that the addition of 2 % FO to broiler chick's diet may stimulate the development of the immune response and improve blood indices, while 4% level was not recommended because of probable off-flavours in the product.
Overcoming Localization Errors due to Node Power Drooping in a Wireless Sensor Network
Authors: Khan Safdar , Daachi Boubaker , Djouani Karim
Published: September 2011

Overcoming Localization Errors due to Node Power Drooping in a Wireless Sensor Network

Received Signal Strength Indication (RSSI) plays a vital role in the range-free localization of sensor nodes in a wireless sensor network and a good amount of research has been made in this regard. One important factor is the battery voltage of the nodes (i.e., the MICAz sensors) which is not taken into account in the existing literature. As battery voltage level performs an indispensable role for the position estimation of sensor nodes through anchor nodes therefore, in this paper, we take into a account this crucial factor and propose an algorithm that overcomes the problem of decaying battery. We show the results, in terms of more precise localization of sensor nodes through simulation. This work is an extension to [1] and now we also use neural network to overcome the localization errors generated due to gradual battery voltage drooping.
Real Time Processing of Networked Passive Coherent Location Radar System
Authors: John Mathew , Inggs Michael , Petri Dario
Published: September 2011

Real Time Processing of Networked Passive Coherent Location Radar System

A Passive Coherent Location (PCL) Radar system, consisting of spatially distributed transmitters and receivers is currently being integrated at the University of Cape Town (UCT). The paper investigates the feasibility of real-time processing of PCL system signals using Graphic Processing Units (GPUs), specifically a study of two distinct clutter cancellation algorithms: ECA (Extensive Cancellation Algorithm) and NLMS (Normalised Least Mean Square). Clutter cancellation is the most computationally demanding part of PCL signal processing. This investigation compares the processing speed-up achieved by GPU over CPU implementations, with very encouraging results.
Applied R&D at the Universities of Applied Sciences
Authors: Frey Urban , Hinderling Christian , Naef Olivier , Shahgaldian Patrick
Published: September 2011

The four institutes of the Universities of Applied Sciences working in the field of Chemistry and Life Sciences present their activities with selected projects.
Innovative Stereo Vision-Based Approach to Generate Dense Depth Map of Transportation Infrastructure
Authors: Rashidi Abbas , Fathi Habib , Brilakis Ioannis
Published: September 2011

Three-dimensional (3-D) spatial data of a transportation infrastructure contain useful information for civil engineering applications, including as-built documentation, on-site safety enhancements, and progress monitoring. Several techniques have been developed for acquiring 3-D point coordinates of infrastructure, such as laser scanning. Although the method yields accurate results, the high device costs and human effort required render the process infeasible for generic applications in the construction industry. A quick and reliable approach, which is based on the principles of stereo vision, is proposed for generating a depth map of an infrastructure. Initially, two images are captured by two similar stereo cameras at the scene of the infrastructure. A Harris feature detector is used to extract feature points from the first view, and an innovative adaptive window-matching technique is used to compute feature point correspondences in the second view. A robust algorithm computes the nonfeature point correspondences. Thus, the correspondences of all the points in the scene are obtained. After all correspondences have been obtained, the geometric principles of stereo vision are used to generate a dense depth map of the scene. The proposed algorithm has been tested on several data sets, and results illustrate its potential for stereo correspondence and depth map generation.
Subthalamic nucleus stimulation for attenuation of pain related to Parkinson disease
Authors: Oshima Hideki , Katayama Yoichi , Morishita Takashi , Sumi Koichiro , Otaka Toshiharu , Kobayashi Kazutaka , Suzuki Yutaka , Fukaya Chikashi , Yamamoto Takamitsu
Published: September 2011

Object

The objective of this study was to evaluate the efficacy of chronic subthalamic nucleus (STN) stimulation for alleviating pain related to Parkinson disease (PD).

Methods

Among 163 consecutive patients undergoing STN stimulation, 69 were identified as experiencing pain preoperatively that was related to their PD. All 69 patients suffering from pain were followed up prospectively for 12 months after surgery. All patients described the severity of their pain according to a visual analog scale (VAS) preoperatively and at 2 weeks, 6 months, and 12 months postoperatively. Pain unrelated to PD was not studied.

Results

Several types of pain related to PD, the categories of which were based on a modification of 2 previous classifications (Ford and Honey), can occur in such patients: 1) musculoskeletal pain, 2) dystonic pain, 3) somatic pain exacerbated by PD, 4) radicular/peripheral neuropathic pain, and 5) central pain. The overall mean VAS score was significantly decreased postoperatively by 75% and 69% at 2 weeks and 6 months, respectively (p < 0.001). The mean VAS score at 12 months was also decreased by 80%, but 6 instances of pain (3 reports of somatic back pain and 3 reports of radicular/peripheral neuropathic pain) required additional spinal surgery to alleviate the pain severity. The results were analyzed using the Wilcoxon signed-rank test and demonstrated a significant reduction in VAS scores at all follow-up assessments (p < 0.001). Musculoskeletal pain and dystonic pain were well alleviated by STN stimulation. In contrast, somatic pain exacerbated by PD and peripheral neuropathic pain originating from lumbar spinal diseases, such as spondylosis deformans and/or canal stenosis, often deteriorated postoperatively despite attenuation of the patients' motor disability. Patients with central pain were poor responders.

Conclusions

This study found that STN stimulation produced significant improvement of overall pain related to PD in patients with advanced PD, and the efficacy continued for at least 1 year. The present results indicate that musculoskeletal pain and dystonic pain responded well to STN stimulation, but patients with back pain (somatic pain) and radicular/peripheral neuropathic pain originating from spinal disease have a potential risk for postoperative deterioration of their pain.
The effects of chemotherapeutic agents on differentiated chordoma cells
Authors: Bayrak Omer Faruk , Aydemir Esra , Gulluoglu Sukru , Sahin Fikrettin , Sevli Serhat , Yalvac Mehmet Emir , Acar Hasan , Ozen Mustafa
Published: September 2011

Object

Chordoma is a rare type of malignant bone tumor and is known to arise from the remnants of the notochord. Resistance to chemotherapy makes the treatment of chordoma difficult; therefore, new approaches need to be developed to cure this disease. Differentiation therapy, using various differentiating agents, is attracting oncologists as a common therapeutic method to treat other tumors. Based on forcing cells to mature into other lineages, differentiation therapy might be an available method to treat chordomas in addition to conventional therapies.

Methods

In this study a chordoma cell line, U-CH1, was exposed to several chemotherapeutic agents including vincristine, doxorubicin, cisplatin, etoposide, fludarabine, methotrexate, nilotinib, and imatinib mesylate under appropriate conditions. The first group of U-CH1 cells was exposed to drugs only and the second group of cells was exposed to the simultaneous treatment of 1 μM all-trans retinoic acid (ATRA) and chemotherapeutic agents in differentiation therapy. The efficacy of the differentiation method was assessed by measuring the viability of U-CH1 cells.

Results

Vincristine, doxorubicin, etoposide, cisplatin, and fludarabine, each at a concentration of 10 μM, decreased the number of chordoma cells when given alone down to 11%, 0%, 30%, 67%, and 3%, respectively. Etoposide and cisplatin, each at a concentration of 10 μM, reduced the percentage of viable chordoma cells in a more effective way when given with 1 μM ATRA simultaneously, reducing the number of viable cells to 14% and 9%, respectively. On the other hand, imatinib and nilotinib, each at a concentration of 3 μM, as well as 10 μM methotrexate, showed no decrease in the number of cancer cells.

Conclusions

The results suggest that chordoma cells may be treated using the differentiation method in a more effective way than when they are treated with chemotherapeutic agents alone. This new approach may be an alternative method to conventional therapies in the treatment of chordoma.
The V2 segment of the vertebral artery: anatomical considerations and surgical implications
Authors: Russo Vittorio M. , Graziano Francesca , Peris-Celda Maria , Russo Antonino , Ulm Arthur J.
Published: September 2011

Object

Iatrogenic injury of the V2 segment of the vertebral artery (VA) is a rare but serious complication and can be catastrophic. The purpose of this study was to characterize the relationship of the V2 segment of the VA to the surrounding anatomical structures and to highlight the potential site and mechanisms of injury that can occur during common neurosurgical procedures involving the subaxial cervical spine.

Methods

Ten adult cadaveric specimens (20 sides) were included in this study. Quantitative anatomical measurements between selected landmarks and the VA were obtained. In addition, lateral mass screws were placed bilaterally, from C-3 to C-7, reproducing either the Magerl technique or a modified technique. The safety angle, defined as the axial deviation from the screw trajectory needed to injure the VA, and the distance from the entry point to the VA were measured at each level for both techniques.

Results

The VA coursed closer to the midline at C3–4 and C4–5 (mean distance [SD] 14.9 ± 1.1 mm) than at C2–3 or C5–6. Within the intertransverse space it coursed closer to the uncinate processes of the vertebral bodies (1.8 ± 1.1 mm) than to the anterior tubercle of the transverse processes (3.4 ± 1.6 mm). The distance between the VA and the uncinate process was less at C3–6 (1.3 ± 0.7 mm) than at C2–3 (3.3 ± 0.8 mm). The VA coursed on average at a distance of 11.9 ± 1.7 mm from the anterior and 4.2 ± 2.6 mm from the posterior aspect of the intervertebral disc space. Lateral mass screw angles were 25° lateral and 39.1° cranial for the Magerl technique, and 36.6° lateral and 46.1° cranial for the modified technique. The safety angle was greater and screw length longer when using this modified technique.

Conclusions

The relation of the V2 segment of the VA to anterior procedures and lateral mass instrumentation at the subaxial cervical spine was reviewed in this study. A detailed anatomical knowledge of the V2 segment of the VA combined with careful preoperative imaging is mandatory for safe cervical spine surgery.
The use of 3D computer graphics in the diagnosis and treatment of spinal vascular malformations
Authors: Takai Keisuke , Kin Taichi , Oyama Hiroshi , Iijima Akira , Shojima Masaaki , Nishido Hajime , Saito Nobuhito
Published: September 2011

Object

Digital subtraction (DS) angiography is the gold standard for diagnosing spinal vascular malformations. Recently, multidetectorrow spiral CT and contrast-enhanced MR angiography have been introduced as screening examinations before DS angiography. These methods, however, do not always determine the accurate location of an arteriovenous shunt because the resulting images lack information about the spinal cord or the dura mater.

Methods

Between April 2009 and December 2010, 13 patients underwent imaging evaluations for spinal vascular malformations at the authors' university hospital. This group included 8 patients with spinal dural arteriovenous fistulas (AVFs), 3 with perimedullary AVFs, and 2 with intramedullary arteriovenous malformations. Using data from these patients, the authors attempted to develop 3D computer graphics (CG) based upon the fusion of 3D rotational angiography and postmyelographic CT. They subsequently verified the accuracy of this imaging method. Ten of these 13 patients underwent surgical treatment for their lesions (11 AVFs), and for these 11 lesions the authors compared the diagnoses obtained using 3D CG with those obtained using conventional DS angiography.

Results

In all 13 cases, 3D CG images of the spinal lesions were successfully developed using the patients' actual data. Four (36%) of 11 AVFs were correctly identified using DS angiography, whereas 10 (91%) were correctly identified using 3D CG. Results from 3D CG of spinal AVFs corresponded well with operative findings, and 3D CG was significantly better than conventional DS angiography at predicting AVF location (p = 0.024, Fisher exact test).

Conclusions

To the authors' knowledge, this is the first reported case series in which 3D CG of spinal vascular malformations was used to provide simultaneous, stereoscopic visualization of the spinal vascular system, spinal cord, dura mater, and bone. The 3D CG method provides precise visual images for the diagnosis and treatment of these lesions.
Analysis of in vivo kinematics of 3 different cervical devices: Bryan disc, ProDisc-C, and Prestige LP disc
Authors: Kowalczyk Izabela , Lazaro Bruno C. R. , Fink Marie , Rabin Doron , Duggal Neil
Published: September 2011

Object

Cervical arthroplasty has emerged as a means of preventing adjacent segment disease by preserving motion, restoring sagittal balance, and mimicking natural spinal kinematics. The purpose of this retrospective in vivo study was to characterize the impact of arthroplasty on sagittal balance and segmental kinematics of the cervical spine.

Methods

Sixty patients receiving the Bryan disc, ProDisc-C, or Prestige LP disc were retrospectively analyzed. Only single-level arthroplasty cases were included in this study. Lateral dynamic radiographs of the cervical spine were evaluated using quantitative measurement analysis software to determine the kinematics at the index level both preoperatively and 1 year postoperatively. Collected parameters included range of motion (ROM), disc angles, shell angles, anterior and posterior disc heights (ADHs/PDHs), translation, and center of rotation (COR). Preoperative and postoperative data were compared using the Student t-test, with p < 0.05 indicating significance.

Results

The Bryan and Prestige LP discs preserved motion, whereas the ProDisc-C increased segmental ROM from extension to flexion. Following surgery, the Bryan disc exhibited significant shell angle kyphosis, while ProDisc-C and Prestige LP retained lordosis. Both ADHs and PDHs decreased following insertion of the Bryan disc. In contrast, the ProDisc-C increased the ADHs and PDHs by 80% and 52%, respectively, and the Prestige LP disc increased the ADHs and PDHs by 20%. Only the ProDisc-C demonstrated significant translation of 0.7 mm. The ProDisc-C shifted the COR x by 0.9 mm anteriorly, while the Prestige LP disc demonstrated a significant superior shift of 2.2 mm in COR y.

Conclusions

All discs adequately maintained ROM at the surgical level. The greatest difference among the 3 devices was in the disc height and index angle measurements.
Interplay of entrainment and rheology in snow avalanches: a numerical study
Authors: Issler Dieter , Pastor Pérez Manuel
Published: September 2011

A one-dimensional evolution equation for the slope-normal velocity profile of a streamwise uniform avalanche over an entrainable bed is derived. The boundary conditions are no slip at the bed, a stress-free surface and constant bed shear stress equal to the shear strength of the snow cover. The resulting equation is solved numerically by means of finite differences on a regular grid with a superposed fine grid near the erosion front that is adjusted at each time-step. The first exploratory simulations yield realistic entrainment rates and show that the entrainment rate tends towards a constant value while the flow depth and the velocity increase linearly with time for all investigated rheologies. It is shown that there indeed exists a rheology-independent asymptotic solution to the equation of motion of an entraining slab if the bottom friction is equal to the bed shear strength; the asymptotic acceleration is found to be half the downslope gravitational acceleration. The model can easily be extended to general path profiles, non-uniform flows and variable snow properties.
Variability of atmospheric freezing-level height and its impact on the cryosphere in China
Authors: Zhang Yinsheng , Guo Y.
Published: September 2011

Abstarct

We used atmospheric air-temperature data from the Chinese radiosonde network to analyze changes in freezing-level heights (FLHs) during the past 48 years and studied their impacts on the cryosphere. We examined radiosonde time-series data from 92 selected Chinese radiosonde network stations. Generally, FLH exhibited a latitudinal zone, declining from the south. The FLH trend during 1958–2005 showed spatial inhomogeneity, most uniform distributions during autumn, and significant upward trends. Temporal variability of FLH in eastern China was briefly associated with El Niño Southern Oscillation events, but the causes of FLH changes in western China require further investigation. FLH in western and northern China has mostly increased since 1958, and might be considered a possible indicator of cryospheric change during the second half of the 20th century. There were significant correlations between FLH and changes in snow cover, glaciers and permafrost.
Sensitivity of snow avalanche simulations to digital elevation model quality and resolution
Authors: Bühler Yves , Christen Marc , Kowalski Julia , Bartelt Perry
Published: September 2011

Digital elevation models (DEMs), represent the three-dimensional terrain and are the basic input for numerical snow avalanche dynamics simulations. DEMs can be acquired using topographic maps or remote-sensing technologies, such as photogrammetry or lidar. Depending on the acquisition technique, different spatial resolutions and qualities are achieved. However, there is a lack of studies that investigate the sensitivity of snow avalanche simulation algorithms to the quality and resolution of DEMs. Here, we perform calculations using the numerical avalance dynamics model RAMMS, varying the quality and spatial resolution of the underlying DEMs, while holding the simulation parameters constant. We study both channelized and open-terrain avalanche tracks with variable roughness. To quantify the variance of these simulations, we use well-documented large-scale avalanche events from Davos, Switzerland (winter 2007/08), and from our large-scale avalanche test site, Vallée de la Sionne (winter 2005/06).We find that the DEM resolution and quality is critical for modeled flow paths, run-out distances, deposits, velocities and impact pressures. Although a spatial resolution of ∼25m is sufficient for large-scale avalanche modeling, the DEM datasets must be checked carefully for anomalies and artifacts before using them for dynamics calculations.
Snow avalanche flow-regime transitions induced by mass and random kinetic energy fluxes
Authors: Bartelt Perry , Meier Lorenz , Buser Othmar
Published: September 2011

We perform a linear-stability analysis of a system of ordinary differential equations describing the motion of dense flowing avalanches. The depth-averaged equations relate the mean translational velocity of the avalanche to the production of turbulent kinetic energy associated with the random motion of the snow granules. Flow friction is described by an extended Voellmy model, where both the Coulomb and turbulent resistance are related to the random kinetic energy. We identify two snow avalanche flow regimes: (1) an unstable frictional flow regime characterized by low random kinetic energy production and (2) a stable, collisional flow regime at the avalanche front. Flow-regime transitions are governed by the production of random kinetic energy, which is controlled by mass. The unstable regime is characterized by a saddle point which the avalanche encounters at the onset of motion and deposition. Depending on the release mass and/or mass growth, the avalanche head will either fluidize, leading to far-reaching avalanches, or starve and die out. At the tail of the avalanche this saddle point also controls the commencement of deposition and therefore the stopping behaviour of avalanches. We discuss the conditions for flow-regime transitions and the enhanced mobility of snow avalanches.
Measuring snow in 3-D using X-ray tomography: assessment of visualization techniques
Authors: Heggli M. , Köchle B. , Matzl M. , Pinzer B.R. , Riche F. , Steiner S. , Steinfeld D. , Schneebeli M.
Published: September 2011

Abstarct

Snow hides its true structure from easy visual observation. One reason is that ice is transparent, so the three-dimensional (3-D) structure is impossible to disentangle. 3-D reconstruction is essential to understand the physical and mechanical properties of snow. In recent years, the techniques to measure and visualize snow in 3-D have improved tremendously. X-ray microtomography is much more user-friendly than the older microtome sectioning techniques. We show different techniques to measure cast and natural snow samples and the steps necessary to produce high-quality data. The simplest way is 3-D renderings. Imaging snow in 3-D definitively challenges our previous view of a snowpack consisting of particles as traditionally seen on a crystal card.
Freezing experiments on unsaturated sand, loam and silt loam
Authors: Watanabe Kunio , Kito Tetsuya , Wake Tomomi , Sakai Masaru
Published: September 2011

Abstarct

Estimating soil-water flow during ground freezing is important for understanding factors affecting spring farming, soil microbial activity below the frozen soil, and permafrost thawing behavior. In this study, we performed a column freezing experiment using three different unsaturated soils (sand, loam and silt loam) to obtain a detailed dataset of temperature, water-content and pressure-head change under freezing conditions. The liquid water content and pressure head in the three soils decreased with decreasing temperature. Three soil temperature stages were found: unfrozen, stagnating near 0˚C and frozen. The temperature and duration of the stagnation stage differed among the soil types. The changes in liquid water content and pressure head during the freezing process were highly dependent on the soil-water retention curve. Water flowed through the frozen area in silt loam and sand, but no water flux was observed in the frozen loam. The freezing soil columns tended to contain more liquid water than estimated from retention curves measured at room temperature, especially at the early stage of freezing.
Local terrain-topography and thermal-properties influence on energy and mass balance of a snow cover
Authors: Adams E.E. , Slaughter A.E. , McKittrick L. , Miller D.A.
Published: September 2011

Abstarct

Snow’s interaction with the environment is an important area in environmental science, particularly as climatic conditions change. We consider the local influence at the slope or smaller scale. Near-surface properties drive the dynamic interface with the atmosphere and with surrounding terrain. While accounting for topography, complex interactions involving energy and mass transfer at the snow surface are considered, using a computer simulation (RadTherm/RT). Digital elevation maps are used to numerically fabricate terrain features and vegetation, while applying appropriate thermal properties to specified terrain types. Conduction, convection radiation and phase change (for dry snow) are considered. Particularly relevant to this study are longwave infrared and shortwave radiation, which in the model account for shadowing, multiple reflective and emissive contributions. An example of a north-facing 30˚, snow-covered clearing bounded by trees is examined using measured meteorological conditions. Applying the same weather conditions, the model is used to examine the difference if the trees are assumed bare or covered with snow. Results indicate that, for the conditions considered, when trees are covered with snow, the open slope is cooler and the snow mass loss is less. Spatial variability across the slope is also noted. Differences are largely due to topographic radiation exchange.
Recent fluctuations of meteorological and snow conditions in Japanese mountains
Authors: Yamaguchi Satoru , Abe Osamu , Nakai Sento , Sato Atsushi
Published: September 2011

Abstarct

Meteorological data from mountainous areas of Japan have been collected by the National Research Institute for Earth Science and Disaster Prevention (NIED) for almost 20 years. The collected long-period data indicate that neither a notable increase in mean winter temperature nor a reduction in snow depth has occurred in these areas. The maximum snow depth, SDmax, and maximum snow water equivalent, SWEmax, show similar fluctuation trends, although with large year-to-year variations in value and a larger fluctuation range for SWEmax than for SDmax. This result suggests that monitoring of only SDmax in mountainous areas is not sufficient for understanding the quantitative fluctuation of water resources originating from snow. The SDmax fluctuation trends in mountainous areas sometimes differ from those in flatland areas because mountain SDmax depends more on winter precipitation than on mean winter air temperature, whereas the opposite is true for flatlands. In addition, the dependence ratio of SDmax on fluctuations in winter precipitation changes with altitude because the distributions of precipitation with air temperature change with altitude.
Glacial lake inventory of Bhutan using ALOS data: methods and preliminary results
Authors: Ukita Jinro , Narama Chiyuki , Tadono Takeo , Yamanokuchi Tsutomu , Tomiyama Nobuhiro , Kawamoto Sachi , Abe Chika , Uda Tsuyoshi , Yabuki Hironori , Fujita Koji , Nishimura Kouichi
Published: September 2011

Abstarct

The Advanced Land Observing Satellite (ALOS) is relatively new. Its optical sensors are capable of making high-resolution digital surface models (DSMs). For the first time, the task of constructing a regional-scale inventory of glacial lakes based on ALOS data has been undertaken. This study presents the data-processing methods and the results of validation and analysis on the ALOS-based glacial lake inventory of Bhutan in the Himalaya. The analysis based on GPS measurements taken at Metatshota lake in the Mangde Chu sub-basin, one of the glacial lakes assessed as presenting a potential flood danger, shows a validation estimate of 9.5 m for the location of the ALOS-based polygon, with a root mean square of 11.7 m. A comparison with digitized data from the International Centre for Integrated Mountain Development (ICIMOD) shows that positioning and evaluation of terrain changes can be significantly improved using ALOS data. Preliminary analysis of the glacial lakes in four sub-basins, Mo Chu, Pho Chu, Mangde Chu and Dangme Chu, reveals that the frequency distribution of lake sizes biases towards smaller lakes. Glacial lakes 0.01–0.05km2 in area account for ~55% of the total number and occupy 13% of the total area. Together our results demonstrate the usefulness of high-resolution ALOS data with accurate DSMs for studying glacial lakes. High priority must be given to continuously improving and updating the glacial lake inventory with high-resolution satellite data.
Parameterization of the shear strength of faceted crystals during equi-temperature metamorphism
Authors: Hirashima Hiroyuki , Abe Osamu , Sato Atsushi
Published: September 2011

Abstarct

Changes in the shear strength of faceted crystals were measured and parameterized under equi-temperature conditions in the laboratory. The air temperature and bottom temperature of the snow layer were controlled to create a large temperature gradient for 8.8 days to make faceted crystals. Subsequently, the temperature gradient was eliminated and the snow was kept under equi-temperature conditions (–5°C and –10°C) for 55 days. During the experiments, the snow density and shear strength were measured six times. The measured shear strength was compared with two empirical relationships based on density. One of these relationships addresses the strength of round grains, whereas the other refers to faceted grains. The measured shear strength approached the calculated value for faceted crystals when the temperature gradient was large, whereas it approached that for rounded grains after the temperature gradient was removed. The dry snow metamorphism factor (DSM factor), which expresses the developmental stage of faceted crystals, was used to model the shear strength increase under equi-temperature conditions. The DSM factor indicates shear strength using an empirical equation based on rounded grains or faceted crystals. It is approximately 0 for rounded grains and 1 for faceted crystals. It decreased from 1.04 to 0.84 and 0.79 at –10°C and –5°C, respectively, in 55 days. These results were incorporated into the numerical snowpack model SNOWPACK, which successfully reproduced the experimentally observed increase in shear strength under equi-temperature conditions.
Interannual changes in sea-ice conditions on the Arctic Sea Route obtained by satellite microwave data
Authors: Shibata Hiroki , Tateyama Kazutaka , Enomoto Hiroyuki , Takahashi Shuuhei
Published: September 2011

Abstarct

With decreases in Arctic sea-ice extent in recent years, the Northern Sea Route (NSR) and Northwest Passage (NWP), which we collectively term the Arctic Sea Route (ASR), have become open for navigation more frequently. The ASR connects the Pacific and Atlantic Oceans, with the NSR following the Siberian coast, and the NWP following the north coast of North America. This study evaluated long-term ice concentrations along both routes using microwave data from the SMMR and SSM/I sensors, and analyzed details using data from the AMSR-E passive microwave sensor. The data were used to determine the number of navigable days according to various sea-ice concentrations. Analysis of SMMR and SSM/I data showed a remarkably large number of navigable days on the NSR since 1995. For the NWP, the low resolution of the SMMR and SSM/I data for the Canadian Arctic Archipelago made analysis difficult, but long-term change in the sea-ice distribution on the ASR was indicated. Analysis of the AMSR-E microwave sensor data revealed navigable days along the NSR in 2002 and from 2005 to 2009 (except 2007). For navigation purposes, the sea-ice decrease in specific regions is important, as well as the decrease across the Arctic Ocean as a whole. For the NWP, numerous navigable days were identified in the period 2006–08.
The Last Great Adventure of the Twentieth Century: The Sealand Affair in British Diplomacy
Authors: Hibberd Grant
Published: September 2011

The concept of micro-nations is not new, but until now little research has been conducted into how Governments have responded to the challenges they present. Such nations are invariably self-declared, often with tiny populations and no visible means of sustaining themselves, and usually to be found on remote islands. The Principality of Sealand, the name bestowed on Roughs Tower, an abandoned British military fort in the North Sea, by its 1960s occupiers, the Bates family, is perhaps the best known example of a micro-nation. The sheer longevity of their claim, which they have been putting forward for over forty years, makes it unique, and therefore worthy of analysis. This article draws together a narrative study of how Whitehall dealt with the Sealand challenge and how different departments of state viewed it in starkly contrasting ways, with a rigorous analysis of the Bates' claim from a legal perspective, setting it against the context of international law as defined by the UN, the EU and individual nations, with an emphasis on marine law and state recognition. The study concludes that the British Government could have done more to close Sealand down and that valuable lessons on inter-departmental co-ordination can still be drawn from this case study today.
A Confrontation between Two Doctrines: The Birth of Struggle for Hegemony in Hebrew Children's Literature during the 1930s and 1940s
Authors: DARR YAEL
Published: September 2011

This article describes a crucial and fundamental stage in the transformation of Hebrew children's literature, during the late 1930s and 1940s, from a single channel of expression to a multi-layered polyphony of models and voices. It claims that for the first time in the history of Hebrew children's literature there took place a doctrinal confrontation between two groups of taste-makers. The article outlines the pedagogical and ideological designs of traditionalist Zionist educators, and suggests how these were challenged by a group of prominent writers of adult poetry, members of the Modernist movement. These writers, it is argued, advocated autonomous literary creation, and insisted on a high level of literary quality. Their intervention not only dramatically changed the repertoire of Hebrew children's literature, but also the rules of literary discourse. The article suggests that, through the Modernists’ polemical efforts, Hebrew children's literature was able to free itself from its position as an apparatus controlled by the political-educational system and to become a dynamic and multi-layered field.
Power and its Mechanics in Children's Fiction: The Case of Roald Dahl
Authors: YU CHEN-WEI
Published: September 2011

This article looks from a Foucauldian perspective at the exercise of power in children's fiction. Roald Dahl's novels are examined as the paradigmatic product of social discourses; and power operates through their circulation. It is argued that Dahl's narratives reflect the author's personal struggle against discourses, which construct both the author himself and his readers as subjects. The article then turns to some critical responses to the novels. It suggests that the author and critics further reprise the roles of fictional child and adult characters, in a constantly shifting dynamic of power relations.
Margaret Mahy: An Adlerian Reading
Authors: WALLS KATHRYN
Published: September 2011

According to the ‘Individual Psychology’ of Alfred Adler (1870–1937), Freud's contemporary and rival, everyone seeks superiority. But only those who can adapt their aspirations to meet the needs of others find fulfilment. Children who are rejected or pampered are so desperate for superiority that they fail to develop social feeling, and endanger themselves and society. This article argues that Mahy's realistic novels invite Adlerian interpretation. It examines the character of Hero, the elective mute who is the narrator-protagonist of The Other Side of Silence (1995) , in terms of her experience of rejection. The novel as a whole, it is suggested, stresses the destructiveness of the neurotically driven quest for superiority. Turning to Mahy's supernatural romances, the article considers novels that might seem to resist the Adlerian template. Focusing, in particular, on the young female protagonists of The Haunting (1982) and The Changeover (1984), it points to the ways in which their magical power is utilised for the sake of others. It concludes with the suggestion that the triumph of Mahy's protagonists lies not so much in their generally celebrated ‘empowerment’, as in their transcendence of the goal of superiority for its own sake.
Invisible Girls: Discourses of Femininity and Power in Children's Fantasy
Authors: LEHTONEN SANNA
Published: September 2011

In children's fantasy, invisibility is a popular motif, typically achieved by using different magic items. Invisibility also serves an important role in feminist discourses of femininity and power. In feminist theory, invisibility has been used to describe the status of females in patriarchal systems, while in fantastic texts invisible females have often literally served as the monstrous Others. However, invisibility has also been seen as a form of empowerment, particularly in fantastic contexts where it can be interpreted both literally and metaphorically. To open up and explore these questions, this article examines the feminist discourses of invisibility, femininity and power in two British children's fantasy novels: The Time of the Ghost (1981) by Diana Wynne Jones and The Ghost Drum (1987) by Susan Price .
Evaluation of communication behavior in persons with dementia during caregivers’ singing
Authors: Engström Gabriella , Marmstål Lena , Williams Christine , Götell Eva
Published: September 2011

The number of persons with dementia (PWD) is increasing rapidly worldwide. Cognitive impairments and communication difficulties are common among PWD. Therefore, gaining mutual togetherness in caring relation between PWD and their caregivers is important. This study was to investigate the effects of music therapeutic care (MTC) during morning care situations on improving verbal and nonverbal communication behaviors in people with dementia. An observation study with 10 PWD participating. Videotaped interactions (VIO) between PWD and their caregivers were conducted during eight weekly sessions, four recordings consisted of usual morning care and four recordings were of morning care with MTC intervention. The Verbal and Nonverbal Interaction Scale was used to analyze the recorded interactions at a later time. The unsociable verbal variable Cursing decreased significantly (P=.037) during MTC when compared with the baseline measurement. A significant (P=.000) reduction was observed for the unsociable nonverbal variable Does not respond to question. MTC significantly (P=.01) increased the mean score for the sociable nonverbal variable – Calm – relaxed. For sociable verbal communication, significant differences were observed for the variables Use coherent communication (P=.012), Use relevant communication (P=.009), Responds to questions (P=.000), Humming (P=.004), Singing (P=.000). MTC during morning care situations can be an effective non-pharmacological treatment, as well as nursing intervention in order to improve sociable communication behaviors, as well as reduce unsociable communication behaviors of PWDs.
Large-Eddy Simulation of a microburst
Authors: Anabor V. , Rizza U. , Nascimento E. L. , Degrazia G. A.
Published: September 2011

Abstract. The three-dimensional structure and evolution of an isolated and stationary microburst are simulated using a time-dependent, high resolution Large-Eddy-Simulation (LES) model. The microburst is initiated by specifying a simplified cooling source at the top of the domain around 2 km a.g.l. that leads to a strong downdraft. Surface winds of the order of 30 m s−1 were obtained over a region of 500 m radius around the central point of the impinging downdraft, with the simulated microburst lasting for a few minutes. These characteristic length and time scales are consistent with results obtained from numerical simulations of microbursts using cloud-resolving models. The simulated flow replicated some of the principal features of microbursts observed by Doppler radars: in particular, the horizontal spread of strong surface winds and a ring vortex at the leading edge of the cold outflow. In addition to the primary surface outflow, the simulation also generated a secondary surge of strong winds that appears to represent a pulsation in the microburst evolution. These results highlight the capability of LES to reproduce complex phenomena like microbursts, indicating the potential usage of LES models to represent atmospheric phenomena of time and space scales between the convective scale and the microscale. These include short-lived convectively-generated damaging winds.
Particle size distribution factor as an indicator for the impact of the Eyjafjallajökull ash plume at ground level in Augsburg, Germany
Authors: Pitz M. , Gu J. , Soentgen J. , Peters A. , Cyrys J.
Published: September 2011

Abstract. During the time period of the Eyjafjallajökull volcano eruption in 2010 increased mass concentration of PM10 (particulate matter, diameter <10 μm) were observed at ground level in Augsburg, Germany. In particular on 19 and 20 April 2010 the daily PM10 limit value of 50 μg m−3 was exceeded. Because ambient particles are in general a complex mixture originating from different sources, a source apportionment method (positive matrix factorization (PMF)) was applied to particle size distribution data in the size range from 3 nm to 10 μm to identify and estimate the volcanic ash contribution to the overall PM10 load in the ambient air in Augsburg. A PMF factor with relevant particle mass concentration in the size range between 1 and 4 μm (maximum at 2 μm) was associated with long range transported dust. This factor increased from background concentration to high levels simultaneously with the arrival of the volcanic ash plume in the planetary boundary layer. Hence, we assume that this factor could be used as an indicator for the impact of the Eyjafjallajökull ash plume on ground level in Augsburg. From 17 to 22 April 2010 long range transported dust factor contributed on average 30 % (12 μg m−3) to PM10. On 19 April 2010 at 20:00 UTC+1 the maximum percentage of the long range transported dust factor accounted for around 65 % (35 μg m−3) to PM10 and three hours later the maximum absolute value with around 48 μg m−3 (61 %) was observed. Additional PMF analyses for a Saharan dust event occurred in May and June 2008 suggest, that the long range transported dust factor could also be used as an indicator for Saharan dust events.
Influence of low spatial resolution a priori data on tropospheric NO2 satellite retrievals
Authors: Heckel A. , Kim S.-W. , Frost G. J. , Richter A. , Trainer M. , Burrows J. P.
Published: September 2011

Abstract. The retrieval of tropospheric columns of NO2 and other trace gases from satellite observations of backscattered solar radiation relies on the use of accurate a priori information. The spatial resolution of current space sensors is often significantly higher than that of the a priori datasets used, introducing uncertainties from spatial misrepresentation. In this study, the effect of spatial under-sampling of a priori data on the retrieval of NO2 columns was studied for a typical coastal area (around San Francisco). High-resolution (15 × 15 km2) NO2 a priori data from the WRF-Chem model in combination with high-resolution MODIS surface reflectance and aerosol data were used to investigate the uncertainty introduced by applying a priori data at typical global chemical transport model resolution. The results show that the relative uncertainties can be large (more than a factor of 2 if all a priori data used is at the coarsest resolution) for individual measurements, mainly due to spatial variations in NO2 profile and surface albedo, with smaller contributions from aerosols and surface height changes. Similar sensitivities are expected for other coastal regions and localised sources such as power plants, highlighting the need for high-resolution a priori data in quantitative analysis of the spatial patterns retrieved from satellite observations of tropospheric pollution.
DOAS-measurement of NO2 formation rate from NOx emissions in the atmosphere
Authors: Frins E. , Osorio M. , Casaballe N. , Belsterli G. , Wagner T. , Platt U.
Published: September 2011

Abstract. In the present work we deal with emissions originating from combustion processes containing SO2, NO and NO2, emitted in the atmosphere by a localized source. We present a method for measuring the NO2-formation rate (due to conversion of NO to NO2) from measurements of SO2- and NO2-slant column densities across different plume sections, under the (usually justified) assumption that the SO2-flux is constant. The advantages of the proposed method are that the measurements can be performed from an arbitrary location, without explicit reference to the wind speed and direction in the plume. We present results of ground based DOAS-measurements of SO2 and NOx emissions from an oil refinery located in the northern part of Montevideo Bay.
Fate of mercury in tree litter during decomposition
Authors: Pokharel A. K. , Obrist D.
Published: September 2011

Abstract. We performed a controlled laboratory litter incubation study to assess changes in dry mass, carbon (C) mass and concentration, mercury (Hg) mass and concentration, and stoichiometric relations between elements during decomposition. Twenty-five surface litter samples each, collected from four forest stands, were placed in incubation jars open to the atmosphere, and were harvested sequentially at 0, 3, 6, 12, and 18 months. Using a mass balance approach, we observed significant mass losses of Hg during decomposition (5 to 23 % of initial mass after 18 months), which we attribute to gaseous losses of Hg to the atmosphere through a gas-permeable filter covering incubation jars. Percentage mass losses of Hg generally were less than observed dry mass and C mass losses (48 to 63 % Hg loss per unit dry mass loss), although one litter type showed similar losses. A field control study using the same litter types exposed at the original collection locations for one year showed that field litter samples were enriched in Hg concentrations by 8 to 64 % compared to samples incubated for the same time period in the laboratory, indicating strong additional sorption of Hg in the field likely from atmospheric deposition. Solubility of Hg, assessed by exposure of litter to water upon harvest, was very low (<0.22 ng Hg g−1 dry mass) and decreased with increasing stage of decomposition for all litter types. Our results indicate potentially large gaseous emissions, or re-emissions, of Hg originally associated with plant litter upon decomposition. Results also suggest that Hg accumulation in litter and surface layers in the field is driven mainly by additional sorption of Hg, with minor contributions from "internal" accumulation due to preferential loss of C over Hg. Litter types showed highly species-specific differences in Hg levels during decomposition suggesting that emissions, retention, and sorption of Hg are dependent on litter type.