bluuebunny/crossref_metadata_2025 huggingface dataset:
Growth, ion composition, and stomatal conductance of peas exposed to salinity
Authors: Maksimović Ivana , Putnik-Delić Marina , Gani Ivana , Marić Jovana , Ilin Žarko
Published: June 2010

Availability of irrigation water of appropriate quality is becoming critical in many regions. Excess salt in irrigation water represents a risk for crop yield, crop quality, and soil properties. During the short vegetation period, field peas require high amounts of water, and irrigation is often indispensable for successful production. Steady presence of NaCl (0.1, 0.2, 0.6 or 1.2 g NaCl L−1 in 1/2 strength Hoagland nutrient solution) under semi-controlled conditions reduced growth and resulted in shorter vegetation. Disturbances in the peas’ water regime were provoked by NaCl, as water content in pea tissues was reduced and stomatal density and stomatal diffusive resistance increased in the presence of higher NaCl concentrations. Concentration of Na+ increased in all pea tissues with increased NaCl concentration in the nutrient medium. In the presence of NaCl, concentrations of K+, Ca2+ and Pi increased in roots, stems and leaves, and decreased and in pods and grains. Concentration ratios Na+/K+, Na+/Ca2+, K+/Ca2+ and (Na++K+)/Ca2+ in various plant parts were affected as well, but magnitudes of changes were variable. Continuous presence of NaCl in concentrations frequently met in irrigation waters significantly reduced pea growth, impaired the water regime, and altered plant chemical composition.
Switching p53-dependent growth arrest to apoptosis via the inhibition of DNA damage-activated kinases
Authors: Hublarova Pavla , Greplova Kristina , Holcakova Jitka , Vojtesek Borivoj , Hrstka Roman
Published: June 2010

Cisplatin and doxorubicin are widely used anticancer drugs that cause DNA damage, which activates the ATM-Chk2-p53 pathway in cancer cells. This activation leads to cell cycle block or apoptosis, depending on the nature of the DNA damage. In an attempt to enhance the effects of these agents, we inhibited ATM/ATR and Chk2, which are known upstream regulators of p53. The cancer cell lines A2780 and ARN8, bearing the wild-type p53 protein, were used to study changes in p53 activation and trans-activation. Our results suggest that the G1-checkpoint, normally activated by DNA damage, is functionally overcome by the action of kinase inhibitors that sensitize cells to apoptosis. Both inhibitors show these effects, albeit with variable intensity in different cell lines, which is promising for other studies and theoretically for use in clinical practice.
Study of the interaction of the C-reactive protein monomer with the U937 monocyte
Authors: Zhao Jing , Shi Xin-He
Published: June 2010

C-reactive protein (CRP) has two structurally distinct isoforms, the CRP pentamer and the CRP monomer. A role for the CRP monomer in atherosclerosis is emerging, but the underlying mechanisms are only beginning to be understood. Monocytes are an important contributor to atherosclerosis, and foam cell formation is the hallmark of atherogenesis. However, whether the CRP monomer can directly interact with the monocytes and modulate their responses remains unknown. Furthermore, although FcγRIII (CD16) has been identified as the receptor for the CRP monomer on neutrophils, its role in mediating the CRP monomer’s biological effects in other cell types has been questioned. In this study, we investigated the interaction of the CRP monomer with the monocytes using the U937 monocytic cell line. The CRP monomer specifically binds to U937 cells. This binding is unique in that it is independent of FcγRs and insensitive to protease digestion of the cell surface proteins. Further assays revealed that the CRP monomer directly incorporates into the plasma membrane. Interestingly, the presence of the CRP monomer efficiently retards oxidized low-density lipoprotein-induced foam cell formation of PMA-differentiated U937 macrophages and peripheral blood monocytic cell-derived macrophages. These findings provide additional evidence for the notion that the CRP monomer is an active CRP isoform that plays a role in atherogenesis via the direct modulation of the behavior of the monocytes.
Spectral analysis of the Forel-Ule ocean colour comparator scale
Authors: Wernand M. R. , van der Woerd H. J.
Published: June 2010

François Alphonse Forel (1890) and Willi Ule (1892) composed a colour comparator scale, with tints varying from indigo-blue to cola brown, to quantify the colour of natural waters, like seas, lakes and rivers. For each measurement, the observer compares the colour of the water above a submersed white disc (Secchi disc) with a hand-held scale of pre-defined colours. The scale can be well reproduced from a simple recipe for twenty-one coloured chemical solutions and because the ease of its use, the Forel-Ule (FU) scale has been applied globally and intensively by oceanographers and limnologists from the year 1890. Indeed, the archived FU data belong to the oldest oceanographic data sets and do contain information on the changes in geobiophysical properties of natural waters during the last century. In this article, we describe the optical properties of the FU scale and its ability to cover the colours of natural waters, as observed by the human eye. The recipe of the scale and its reproduction is described. The spectral transmission of the tubes and their respective chromaticity coordinates are presented. The FU scale, in all its simplicity, is found to be an adequate ocean colour comparator scale. The scale is well characterized, stable and observations are reproducible. Thus, the large historic data sets of FU measurements are coherent and well calibrated. Moreover, the scale can be coupled to contemporary multi-spectral observations with hand-held and satellite-based spectrometers. A reintroduction of the FU scale is recommended to expand the historical database and to facilitate a tie-in with present satellite ocean colour observations by tranforming MERIS normalized multi-band reflectance image into a FU indexed image.
Performance considerations for continuous-wave and pulsed laser line scan (LLS) imaging systems
Authors: Caimi F. M. , Dalgleish F. R.
Published: June 2010

Extended range underwater optical imaging techniques can be classified into one of two broad categories; those which use synchronously scanned narrow source and receiver paths to restrict both back-scattered and forward-scattered light reaching the receiver (continuouswave laser line scan); and those which use pulsed sources and time-gating to remove back-scatter noise (pulsed laser line scan and pulse-gated laser line scan). Laser line scan systems are observed to perform at up to 5 to 6 optical attenuation lengths, but greater standoff distances are desirable for seabed imaging using the growing fleet of autonomous underwater vehicles (AUVs). Currently, a moderate physical separation between laser and receiver is necessary to reject near-field multiple back-scatter, which imposes restrictions on AUV miniaturization. Recent experiments and theoretical modeling reveal that significant imaging improvements are possible over the existing continuous-wave laser line scan systems (LLS), by using a pulsed-gated version of the LLS (PG-LLS). However, the use of such a technique has a greater advantage in reducing the overall form factor over conventional LLS imaging system, as well as providing greater depth-of-field. In this paper, we present experimental results comparing both LLS and PG-LLS systems for several source-receiver separations and standoff distances. These results compare favorably with images obtained from validated LLS image simulation tools, and indicate the potential for reducing the source-receiver separation and therefore the system size.
Terahertz analysis of an East Asian historical mural painting
Authors: Fukunaga K. , Hosako I. , Kohdzuma Y. , Koezuka T. , Kim M.-J. , Ikari T. , Du X.
Published: June 2010

Terahertz (THz) spectroscopy and THz imaging techniques are expected to have great potential for the non-invasive analysis of artworks. We have applied THz imaging to analyse the historic mural painting of a Lamaism temple by using a transportable time-domain THz imaging system; such an attempt is the first in the world. The reflection image revealed that there are two orange colours in the painting, although they appear the same to the naked eye. THz imaging can also estimate the depth of cracks. The colours were examined by X-ray fluorescence and Raman spectroscopy, and the results were found to be in good agreement. This work proved that THz imaging can contribute to the non-invasive analysis of cultural heritage.
How Moving to Quebec Has Affected My Theology
Authors: Baum Gregory
Published: June 2010

Abstract:

In this lecture given at the 2009 meeting of the American Academy of Religion in Montreal, Gregory Baum reports how moving to Quebec has affected his practical theology. He mentions three issues of great importance to this French-speaking society that demanded new ethical reflection on his part: the character of an ethically acceptable nationalism, the appropriate response to the cultural weight of English in North America, and an acceptable alternative to Canadian multiculturalism. Thanks to the Montreal-based Karl Polanyi Institute, Baum discovered Karl Polanyi's socio-economic thought critical of the unregulated market system, that differs from Marxism, attends to cultural and ethical issues, and reveals a certain affinity with Catholic social teaching. Polanyi offers a theoretical foundation for the social economy and community efforts to reform society from the bottom up.
Magnetic resonance imaging dynamics of contrast medium uptake in vestibular schwannomas
Authors: Rampp Stefan , Scheller Christian , Prell Julian , Engelhorn Tobias , Strauss Christian , Rachinger Jens
Published: June 2010

Object

Efficacy of radiosurgery in vestibular schwannoma (VS) is usually documented by changes of tumor size and by loss of contrast enhancement in MR imaging within the central portion of the lesion. Until now, however, correlation between contrast enhancement and timing of image acquisition in nontreated VS has not been analyzed systematically. The authors undertook this study to investigate changes in contrast enhancement with respect to latency of image acquisition after contrast agent administration.

Methods

The dynamics of contrast medium uptake were evaluated with T1-weighted VIBE MR imaging sequences performed immediately and 1.5, 3.5, 4.5, 9.5, and 11.5 minutes after administration of single dose of Gd in 21 patients with nontreated medium- to large-sized VSs. Signal-to-noise (SNR) and contrast-to-noise ratio (CNR) of tumors were evaluated, and volumes of central nonenhancing areas (NEAs) were determined.

Results

The interior appearance of the tumors changed considerably over time. The NEA significantly diminished in size (p < 0.0001, Friedman test) and almost completely disappeared in all but 2 patients. Compared to images at 1.5 minutes, NEA volumes decreased to a median of 36% at 3.5 minutes and 34% at 4.5 minutes, showing smaller changes after that—9% at 9.5 minutes and 3% at 11.5 minutes. Tumor SNR and CNR increased over time. The maximum change in the median values for SNR and CNR were a 72% increase and 117% increase, respectively; both occurred at 1.5 minutes after Gd administration.

Conclusions

Contrast enhancement in VS MR imaging varies according to the duration of the delay between contrast agent administration and image acquisition. Postradiotherapy changes in contrast enhancement of VS can therefore not be attributed only to effective radiotherapy. So-called “loss of central contrast enhancement” may be falsely detected because of timing. A standardized protocol with defined timing of image acquisition may increase comparability of contrast uptake in VS.
Gastroesophageal Reflux Disease  An Update
Authors: Mushtaque AR
Published: June 2010

Gastroesophageal reflux disease (GERD) is a common disease and a considerable burden on healthcare resources. Definitions and terminology have been a source of confusion for GERD. The ‘Montreal definition' is the first ever global consensus definition of GERD. The esophageal and extraesophageal syndromes are now considered the two constituent syndromes of GERD. The pathogenesis of gastroesophageal reflux is multi-factorial and a failure of the anti-reflux barrier allowing the stomach content to enter the esophagus is the target of interest. Heartburn and acid regurgitation are the typical symptoms of the disease, although some patients may have atypical manifestations of GERD. The long term complication of GERD includes esophageal stricture, Barrett's esophagus with consequent increase in the risk of esophageal adenocarcinoma. Diagnosis of GERD can usually be established on the basis of a careful history and physical examination. Detailed diagnostic studies are not necessary in a patient presenting with typical symptoms with no alarming features. Patients with alarming feature in addition to their GERD symptoms require prompt investigation and usually endoscopy is preferred. Treatment of GERD is directed at acid suppression through the use of lifestyle modifications and pharmacologic agents from over-the-counter (OTC) agents ranging from antacids to proton pump inhibitors (PPIs). New algorithm of treatment of GERD has also been proposed. Antireflux surgery, including open and laparoscopic, and newer endoscopic procedures are alternative modalities of treatment in case of failure of medical therapy. Key words: Gastroesophageal reflux disease; Montreal definition; Esophageal syndrome; Extraesophageal syndrome; Heartburn; Regurgitation. DOI: 10.3329/bjms.v9i1.5227 Bangladesh Journal of Medical Science Vol.09 No.1 Jan 2010 14-26
Segmentation and Classification of Jaw Bone CT images using Curvelet based Texture features
Authors: Reddy TK , Kumaravel N
Published: June 2010

The evaluation of jaw bone trabecular structure and quality could be useful for characterization and response of the bone for dental implants. Current clinical methods for assessment of bone quality at the implant sites largely depend on assessing bone mineral density using Dual energy X-ray absorptionometry. However, this does not provide any information about bone structure which is considered to be an equally important factor in assessing bone quality. This paper presents a novel approach for computer analysis of trabecular (or cancellous) bone structure using multiresolution based texture analysis to evaluate changes taking place in the architecture of bone with age and gender. The findings are compared with Hounsfield Units measured from the CT machine at different sites, which is a standard reference. Fifty patients were subjected to clinical CT to obtain the CT number and texture based architectural parameters respectively. In each site texture features were extracted using gray level co-occurrence matrices (GLCM), Run length matrices, Histogram and curvelet based statistical & co occurrence analysis. A very difficult problem in classification techniques is the choice of features to distinguish between classes. However the performance of any classifier is not optimized when all features are used. The feature optimization problem is addressed using Principle component analysis in terms of the best recognition rate and the optimal number of features. Testing this on a series of 120 image sections of trabecular bone with normal, partial and total edentulous patients correctly classified over 90% of the porous bone group with an overall accuracy of 87.8%-95.2%.The results shows that by using the Classification & Regression Tree approach the combination of the features from gray level and Ist order statistics achieved overall classification accuracy in the range of 87.8- 90.24%. Features selected from the curvelet based co occurrence matrix performed better with overall classification accuracy of 92.89%.In order to increase the success rate the classification is done using the combination of curvelet statistical features and curvelet co occurrence features as feature vector and using this, a mean success rate of 95.2% is obtained. Keywords: Multiresolution analysis; Texture features; curvelets; Computed Tomography; Regression analysis; GLRLM. DOI: 10.3329/bjms.v9i1.5229 Bangladesh Journal of Medical Science Vol.09 No.1 Jan 2010 33-43
Variation in leaf stomatal traits of 28 tree species in relation to gas exchange along an edaphic gradient in a Bornean rain forest
Authors: Russo Sabrina E. , Cannon Whitney Logan , Elowsky Christian , Tan Sylvester , Davies Stuart J.
Published: June 2010

• Premise of the study: Quantifying variation in functional traits associated with shifts in the species composition of plant communities along resource gradients helps identify environmental attributes important for community assembly. Stomates regulate the balance between carbon assimilation and water status in plants. If environmental attributes affecting photosynthetic water‐use efficiency govern species distribution along an edaphic gradient, then adaptive variation in stomatal traits of plant species specializing on different soils should reflect belowground resource availability.

• Methods: We tested this hypothesis by quantifying stomatal trait variation in understory saplings of 28 Bornean tree species in relation to gas exchange and water‐use efficiency (WUE).

• Key results: Comparisons between congeneric specialists of the more fertile, moister clay and the less fertile, well‐drained sandy loam revealed little evidence of similar shifts in stomatal traits across genera, nor was stomatal pore index correlated with gmax, Amax, or WUE (Amax/gmax or Δ13C), suggesting that stomates may be overbuilt in these shaded juveniles. Amax was higher on sandy loam, likely due to higher understory irradiance there, but there were no other significant differences in gas exchange or WUE.

• Conclusions: Despite substantial diversity in stomatal anatomy, there were few strong relationships between stomatal, photosynthetic, and WUE traits in relation to soil resources. Routine differences in water availability therefore may not exert a dominant control on the distributions of these Bornean tree species. Furthermore, the clades represented by these 12 genera may possess alternative functional designs enabling photosynthetic WUE that is sufficient to these humid, understory environments, due to whole plant‐functional integration of stomatal traits with other, unmeasured traits influencing gas exchange.
Long-term record of pH in the Dutch coastal zone: a major role for eutrophication-induced changes
Authors: Provoost P. , van Heuven S. , Soetaert K. , Laane R. , Middelburg J. J.
Published: June 2010

Abstract. Recent observations and modelling studies suggest that eutrophication-related biogeochemical changes can mask atmospheric CO2-induced pH decreases. Data collected by the Dutch monitoring authorities in different coastal systems (North Sea, Wadden Sea, Ems-Dollard, Eastern Scheldt and Scheldt estuary) since 1975 provide an excellent opportunity to test whether this is the case in the Dutch coastal zone. The time-series were analysed using Multi-Resolution Analysis (MRA) which resulted in the identification of system-dependent patterns on both seasonal and intra-annual time scales. The observed rates of change greatly exceed those expected from enhanced CO2 uptake, thus confirming that eutrophication can play a dominant role in ocean acidification.
A case study on the use of appropriate surrogates for antecedent moisture conditions (AMCs)
Authors: Ali G. A. , Roy A. G.
Published: June 2010

Abstract. While a large number of non-linear hillslope and catchment rainfall-runoff responses have been attributed to the temporal variability in antecedent moisture conditions (AMCs), two problems emerge: 1) the difficulty of measuring AMCs, and 2) the absence of explicit guidelines for the choice of surrogates or proxies for AMCs. This paper aims at determining whether or not multiple surrogates for AMCs should be used in order not to bias our understanding of a system hydrological behaviour. We worked in a small forested catchment, the Hermine, where soil moisture has been measured at 121 different locations at four depths on 16 occasions. Without making any assumption on active processes, we used various linear and nonlinear regression models to evaluate the point-scale temporal relations between actual soil moisture contents and selected meteorological-based surrogates for AMCs. We then mapped the nature of the "best fit" model to identify 1) spatial clusters of soil moisture monitoring sites whose hydrological behaviour was similar, and 2) potential topographic influences on these behaviours. Two conclusions stood out. Firstly, it was shown that the sole reference to AMCs indices traditionally used in catchment hydrology, namely antecedent rainfall amounts summed over periods of seven or ten days, would have led to an incomplete understanding of the Hermine catchment dynamics. Secondly, the relationships between point-scale soil moisture content and surrogates for AMCs were not spatially homogeneous, thus revealing a mosaic of linear and nonlinear catchment "active" and "contributing" sources whose location was often controlled by surface terrain attributes or the topography of a soil-confining layer interface. These results represent a step forward in developing a hydrological conceptual model for the Hermine catchment as they indicate depth-specific processes and spatially-variable triggering conditions. Further investigations are, however, necessary in order to derive general guidelines for the choice of the best surrogates for AMCs in a catchment.
Invasive fungal disease in patients treated for newly diagnosed acute leukemia
Authors: Hammond Sarah P. , Marty Francisco M. , Bryar Julie M. , DeAngelo Daniel J. , Baden Lindsey R.
Published: June 2010

Invasive fungal disease (IFD) is a significant cause of morbidity and mortality in patients undergoing treatment for acute leukemia (AL). Antifungal prophylactic strategies are associated with significant toxicities and cost. We performed a retrospective study of the incidence and risk factors for IFD among patients newly diagnosed with and treated for AL between January 1, 2004 and July 1, 2006. Patient follow up concluded January 1, 2007. Among 231 patients with newly diagnosed AL, 31 (13.4%) developed IFD by the end of follow up, 24 (10.4%) of whom developed IFD within the first 100 days after diagnosis of AL. The cumulative probability of developing IFD was 5.9% by 30 days and 11.1% at 100 days after AL diagnosis. Patients who had persistent leukemia after an initial course of induction chemotherapy were significantly more likely to develop IFD than those who did not have evidence of persistent leukemia (14/65 (21.5%) vs. 15/148 (10.1%), P = 0.03). In a time‐dependent Cox model, the adjusted hazard ratio for developing IFD within the first 100 days of AL diagnosis based on the number of days of neutropenia in that period was 4.85 (95% confidence interval: 1.52, 15.4). Those patients with more days of neutropenia in the first 100 days after AL diagnosis, such as those who did not achieve remission after a first course of induction chemotherapy, were more likely to develop IFD. Am. J. Hematol., 2010. © 2010 Wiley‐Liss, Inc.
Conservation problems with hypothelminorheic Niphargus species (Amphipoda: Niphargidae)
Authors: Fišer Cene , Konec Marjeta , Kobe Zala , Osanič Miha , Gruden Pina , Potočnik Hubert
Published: June 2010

The hypothelminorheic is a unique superficial subterranean habitat, harbouring troglomorphic species that are unique to this habitat or share species with other subterranean habitats. These species are especially vulnerable to disturbance and human impact.

The ecological needs of the sympatric Niphargus slovenicus and Niphargus sphagnicolus from central Slovenia were examined in order to assess whether similar conservation strategies could be applied for the two species.

Their habitat patches appeared to be variable with respect to abiotic factors, and the ecological requirements of the two species differ. A major discriminatory factor is pH.

The results imply that the conservation strategies for sympatric hypothelminorheic species cannot be generalized; additional research for the case study is discussed. Copyright © 2010 John Wiley & Sons, Ltd.
Phytoglycoprotein (75 kDa) inhibits expression of interleukin‐1β stimulated by DEHP in human mast cells
Authors: Oh Phil‐Sun , Lim Kwang , Lim Kye‐Taek
Published: June 2010

The purpose of this study is to investigate the inhibitory effect of a glycoprotein (CTB glycoprotein, 75 kDa) isolated from Cudrania tricuspidata Bureau (CTB) on the di‐(2‐ethylhexyl)phthalate (DEHP) induced expression of allergic‐inflammation‐related mediators in human mast cells. The changes on the levels of intracellular reactive oxygen species (ROS), mitogen‐activated protein kinase (MAPK), transcription factor [nuclear factor (NF)‐κB], and allergic inflammatory mediators [cyclooxygenase (COX)‐2 and interleukin (IL)‐1β] were evaluated using Western blot and RT‐PCR. Our results showed that the CTB glycoprotein in the presence of DEHP inhibits the production of intracellular ROS, the phosphorylation of ERK1/2, and p38 MAPK in HMC‐1 cells. In addition, the CTB glycoprotein has suppressive effects on the transcriptional activation of NF‐κB, and on the expression levels of COX‐2 and IL‐1β in DEHP‐treated HMC‐1 cells. In conclusion, the CTB glycoprotein has a strong anti‐inflammatory effect on the activities of allergic inflammatory mediators indirectly caused by DEHP in HMC‐1 cells. Copyright © 2010 John Wiley & Sons, Ltd.
Growth and thermal studies on pure ADP, KDP and mixed K1‐x(NH4)xH2PO4 crystals
Authors: Shenoy P. , Bangera K. V. , Shivakumar G. K.
Published: June 2010

The investigations on the formation of mixed crystals of ammonium dihydrogen orthophosphate (ADP) and potassium dihydrogen orthophosphate (KDP) i.e. potassium ammonium dihydrogen phosphate, K1‐x(NH4)xH2PO4 have been presented in this paper. Pure and mixed crystals of ADP and KDP have been grown by slow evaporation technique from the supersaturated solution at an ambient temperature 26±1 °C for ammonium concentration x in the range 0.0 ≤ x ≤ 1.0 in the case of mixed crystals. Crystal compositions were determined by flame atomic absorption spectroscopy and chemical analysis. The results of the X‐ray analysis of the grown crystals are also reported. Thermogravimetric analysis (TGA) and differential thermal analysis (DTA) were used to study the kinetic process of dehydration and the high temperature phase behaviour. DTA showed the distinct thermal events attributed to dehydration of ADP, KDP and K1‐x(NH4)xH2PO4. The results of thermal analysis and chemical analysis are consistent with each other. (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Morphology of silver bromide crystals produced at presence ofN,N‐dimethylformamide
Authors: Dyonizy A. , Nowak P.
Published: June 2010

The study deals with examination of conditions that are necessary to obtain flat crystals of silver bromide that grow in a water and gelatine crystallization environment whereN,N‐dimethylformamide is used as the agent that is conducive to complexing of sparingly soluble silver bromide. The examination focused on the issue how changes in volumetric concentration ofN,N‐dimethylformamide as well as concentration of excessive ions of silver bromide in the dispersive solution affect morphology and size of newly created of silver bromide. The completed experiments enabled to determine boundary limits of bothN,N‐dimethylformamide and bromide ions concentration where suspensions of silver bromide crystals exhibit predominant content of triangular, transient and hexagonal flat forms with very high aspect ratio. (© 2010 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Rill development and soil erosion: a laboratory study of slope and rainfall intensity
Authors: Berger Catherine , Schulze Marcel , Rieke‐Zapp Dirk , Schlunegger Fritz
Published: June 2010

A total of 15 rainfall simulation experiments were conducted in a 1 m by 2 m box varying slope (10, 20, 30%) and rainfall intensity (60, 90, 120 mm h−1). The experiments were performed to study how rill networks initiate and evolve over time under controlled conditions with regard to the treatment variables considered, and to allow for input in a computer simulation model. Runoff and sediment yield samples were collected. Digital elevation models were calculated by means of photogrammetry for several time steps of most experiments. The soil used in the experiments was a basal till derived Cambisol typical for the Swiss Plateau. While significant differences were found for sediment yield, runoff did not vary significantly with treatment combinations. Increasing rainfall intensity had a larger effect on sediment yield than increasing slope. Rill density and energy expenditure decreased with time, suggesting that energy expenditure was a useful parameter to describe the emergence of rill network at the laboratory scale. Copyright © 2010 John Wiley & Sons, Ltd.
Fire risks of burning asphalt
Authors: Schartel B. , Bahr H. , Braun U. , Recknagel C.
Published: June 2010

Eyewitnesses describe burning pavement surfaces in extreme fire scenarios. However, it was believed that the pavement plays a negligible role in comparison to other items feeding such an extreme fire at the same time. The asphalt mixtures used differ widely, thus raising the question as to whether this conclusion holds for all kinds of such materials. Three different kinds of asphalt mixtures were investigated with the aim of benchmarking the fire risks. Cone calorimeter tests are performed at an irradiance of 70kWm−2. All three investigated asphalts burn in extreme fire scenarios. The fire response (fire load, time to ignition, maximum heat release rate and smoke production) is quite different and varies by factors of up to 10 when compared to each other. The fire load per mass is always very low due to the high content of inert minerals, whereas the effective heat of combustion of the volatiles is quite typical of non‐flame retarded organics. The heat release rate and fire growth indices are strongly dependent on the fire residue and thus the kind of mineral filler used. Comparing with polymeric materials, the investigated Mastic Asphalt and Stone Mastic Asphalt may be called intrinsically flame resistant, whereas the investigated Special Asphalt showed a pronouncedly greater fire risk with respect to causing fire growth and smoke. Thus the question is raised as to whether the use of certain kinds of asphalts in tunnels must be reconsidered. Apart from the binder used, the study also indicates varying the kind of aggregate as a possible route to eliminate
the problem. Copyright © 2010 John Wiley & Sons, Ltd.
SIMULATION OF A GROUNDWATER ARTIFICIAL RECHARGE IN A SEMI‐ARID REGION OF IRAN
Authors: Tizro A. Taheri , Voudouris K. S. , Akbari K.
Published: June 2010

The Bahar aquifer is one of the most economically important aquifers in the western part of Iran, covering the water demands for irrigation supplies. Intensive pumping for irrigation has caused a water table decline. The local water organisation has constructed a water storage structure to augment the groundwater resources. Groundwater recharge using water from the river via 13 dug wells and a related structure has been estimated as 2.7 million m3, for the hydrological year 2002–2003. A three‐dimensional model was developed to predict the aquifer system response. The effect of radial flow was found to be 4 km, and the area covering this recharge more than 40 km2. The results of the numerical model could be used by local authorities and decision makers for groundwater resources management and planning. Finally, it is concluded that aquifer recharge is one environmental solution, as a part of integral water resources management. Copyright © 2010 John Wiley & Sons, Ltd.
Determining optimal groundwater table depth for maximizing cotton production in the Sardarya province of Uzbekistan
Authors: Qureshi Asad Sarwar , Eshmuratov D. , Bezborodov G.
Published: June 2010

Poor on‐farm irrigation practices and rising groundwater table depths are the major reasons for low cotton yields in the Sardarya province of Uzbekistan. To ensure sustainability of cotton production in the area, precise calculations of irrigation requirements are needed to optimize crop yields and to keep groundwater table depth below the root zone to avoid soil salinization. To determine optimal groundwater table depth and irrigation amounts for the Sardarya province of Uzbekistan, the Soil–Water–Atmosphere–Plant (SWAP) model was used. SWAP was calibrated and validated using measured data from an experimental cotton field during the agricultural year of 2006 and 2007. The calibrated SWAP model was then used to simulate optimal groundwater table depth and irrigation amounts. The simulation results show that for the existing conditions in the study area, a groundwater table depth of approximately 200 cm together with an irrigation application of 2500 m3 ha−1 will be the most appropriate combination for optimal cotton yields (≈ 3.0 t ha−1). However, to achieve maximum potential yields of cotton (5–6 t ha−1), leaching of excessive salts from the root zone through freshwater application would be imperative. This would require rehabilitation of the existing drainage network in the area. Copyright © 2010 John Wiley & Sons, Ltd.
Empirical‐statistical downscaling and error correction of daily precipitation from regional climate models
Authors: Jakob Themeßl Matthias , Gobiet Andreas , Leuprecht Armin
Published: June 2010

Although regional climate models (RCMs) are powerful tools for describing regional and even smaller scale climate conditions, they still feature severe systematic errors. In order to provide optimized climate scenarios for climate change impact research, this study merges linear and nonlinear empirical‐statistical downscaling techniques with bias correction methods and investigates their ability for reducing RCM error characteristics. An ensemble of seven empirical‐statistical downscaling and error correction methods (DECMs) is applied to post‐process daily precipitation sums of a high‐resolution regional climate hindcast simulation over the Alpine region, their error characteristics are analysed and compared to the raw RCM results.

Drastic reductions in error characteristics due to application of DECMs are demonstrated. Direct point‐wise methods like quantile mapping and local intensity scaling as well as indirect spatial methods as nonlinear analogue methods yield systematic improvements in median, variance, frequency, intensity and extremes of daily precipitation. Multiple linear regression methods, even if optimized by predictor selection, transformation and randomization, exhibit significant shortcomings for modelling daily precipitation due to their linear framework. Comparing the well‐performing methods to each other, quantile mapping shows the best performance, particularly at high quantiles, which is advantageous for applications related to extreme precipitation events. The improvements are obtained regardless of season and region, which indicates the potential transferability of these methods to other regions. Copyright © 2010 Royal Meteorological Society
Stochastic micromechanical model of the deterioration of asphalt mixtures subject to moisture diffusion processes
Authors: Caro Silvia , Masad Eyad , Sánchez‐Silva Mauricio , Little Dallas
Published: June 2010

The deleterious effect of moisture in the microstructure of asphalt mixtures, usually referred to as moisture damage, has been recognized as a main cause of early deterioration of asphalt pavements. The initiation and evolution of moisture‐related deterioration is strongly influenced by the internal air void structure of asphalt mixtures. Despite its importance, the majority of works conducted on the micromechanical modeling of asphalt mixtures overlook the role of the air void structure, mainly because of its high complexity and variability. This paper explores the influence of air void variability on the performance of asphalt mixtures subjected to moisture diffusion processes. A stochastic modeling technique based on random field theory was used to generate internal distributions of physical and mechanical properties of the asphalt matrix of the mixture that depend on probable air voids distributions. The analysis was conducted by means of a coupled numerical micromechanical model of moisture damage. The results showed that the variability and distribution of air voids are decisive in determining the moisture‐dependent performance of asphalt mixtures. Furthermore, it was also shown that a stochastic characterization of the diverse air void configurations is a feasible and useful approach to better represent and understand mechanically related deterioration processes in asphalt mixtures. Copyright © 2010 John Wiley & Sons, Ltd.
The time window of MRI of murine atherosclerotic plaques after administration of CB2 receptor targeted micelles: inter‐scan variability and relation between plaque signal intensity increase and gadolinium content of inversion recovery prepared versus non‐prepared fast spin echo
Authors: te Boekhorst B. C. M. , Bovens S. M. , van de Kolk C. W. A. , Cramer M. J. M. , Doevendans P. A. F. M. , ten Hove M. , van der Weerd L. , Poelmann R. , Strijkers G. J. , Pasterkamp G. , van Echteld C. J. A.
Published: June 2010

Single fast spin echo scans covering limited time frames are mostly used for contrast‐enhanced MRI of atherosclerotic plaque biomarkers. Knowledge on inter‐scan variability of the normalized enhancement ratio of plaque (NERplaque) and relation between NERplaque and gadolinium content for inversion‐recovery fast spin echo is limited. Study aims were: evaluation of (1) timing of MRI after intravenous injection of Cannabinoid‐2 receptor (CB2‐R) (expressed by human and mouse plaque macrophages) targeted micelles; (2) inter‐scan variability of inversion‐recovery fast spin echo and fast spin echo; (3) relation between NERplaque and gadolinium content for inversion‐recovery fast spin echo and fast spin echo. Inversion‐recovery fast spin echo/fast spin echo imaging was performed before and every 15 min up to 48 h after injection of CB2‐R targeted or control micelles using several groups of mice measured in an interleaved fashion. NERplaque (determined on inversion‐recovery fast spin echo images) remained high (∼2) until 48 h after injection of CB2‐R targeted micelles, whereas NERplaque decreased after 36 h in the control group. The inter‐scan variability and relation between NERplaque and gadolinium (assessed with inductively coupled plasma‐ mass spectrometry) were compared between inversion‐recovery fast spin echo and fast spin echo. Inter‐scan variability was higher for inversion‐recovery fast spin echo than for fast spin echo. Although gadolinium and NERplaque correlated well for both techniques, the NER of plaque was higher for inversion‐recovery fast spin echo than for fast spin echo. In mice injected with CB2‐R targeted micelles, NERplaque can be best evaluated at 36–48 h post‐injection. Because NERplaque was higher for inversion‐recovery fast spin echo than for fast spin echo, but with high inter‐scan variability, repeated inversion‐recovery fast spin echo imaging and averaging of the obtained NERplaque values is recommended. Copyright © 2010 John Wiley & Sons, Ltd.
Theoretical models of the diffusion weighted MR signal
Authors: Yablonskiy Dmitriy A. , Sukstanskii Alexander L.
Published: June 2010

Diffusion MRI plays a very important role in studying biological tissue structure and functioning both in health and disease. Proper interpretation of experimental data requires development of theoretical models that connect the diffusion MRI signal to salient features of tissue microstructure at the cellular level. In this review, we present some models (mostly, relevant to the brain) for describing diffusion attenuated MR signals. These range from the simplest approach, where the signal is described in terms of an apparent diffusion coefficient, to rather complicated models, where consideration is given to signals originating from extra‐ and intracellular spaces and where account is taken of the specific geometry and orientation distribution of cells. To better understand the characteristics of the diffusion attenuated MR signal arising from the complex structure of whole tissue, it is instructive to appreciate first the characteristics of the signal arising from simple single‐cell‐like structures. For this purpose, we also present here a theoretical analysis of models allowing exact analytical calculation of the MR signal, specifically, a single‐compartment model with impermeable boundaries and a periodic structure of identical cells separated by permeable membranes. Such pure theoretical models give important insights into mechanisms contributing to the MR signal formation in the presence of diffusion. In this review we targeted both scientists just entering the MR field and more experienced MR researchers interested in applying diffusion methods to study biological tissues. Copyright © 2010 John Wiley & Sons, Ltd.
Improved R2* measurement accuracy with absolute SNR truncation and optimal coil combination
Authors: Yin Xiaoming , Shah Saurabh , Katsaggelos Aggelos K. , Larson Andrew C.
Published: June 2010

Accurate R2* measurements are critical for many abdominal imaging applications. Conventionally, R2* maps are derived via the monoexponential fitting of signal decay within a series of gradient‐echo (GRE) images reconstructed from multichannel datasets combined using a root sum‐of‐squares (RSS) approach. However, the noise bias at low‐SNR TEs from RSS‐reconstructed data often causes the underestimation of R2* values. In phantom, ex vivo animal model and normal volunteer studies, we investigated the accuracy of low‐SNR R2* measurement when combining truncation and coil combination methods. The accuracy for R2* estimations was shown to be affected by the intrinsic R2* value, SNR level and the chosen reconstruction method. The R2* estimation error was found to decrease with increasing SNR level, decreasing R2* value and the use of the optimal B1‐weighted combined (OBC) image reconstruction method. Data truncation based on rigorous voxel‐wise SNR estimates can reduce R2* measurement error in the setting of low SNR with fast signal decay. When optimal SNR truncation thresholds are unknown, the OBC method can provide optimal R2* measurements given the minimal truncation requirements. Copyright © 2010 John Wiley & Sons, Ltd.
Design of ℋ︁∞ fuzzy controllers for nonlinear systems with random data dropouts
Authors: Zhang Jinhui , Xia Yuanqing
Published: June 2010

The problem of ℋ︁∞ control of nonlinear networked control systems subject to random data dropout is concerned in this paper. The random data dropout, because of the limited bandwidth of the network channels, could exist in the communication channels both from the sensor to the controller and from the controller to the actuator simultaneously. The nonlinear plant is represented by the well‐known Takagi–Sugeno fuzzy model and the random data dropout is expressed by the Bernoulli random binary distribution. In the presence of random data dropout, two control schemes, state feedback and static output feedback, are proposed to design ℋ︁∞ controllers such that the closed‐loop system is stochastically stable and preserves a guaranteed ℋ︁∞ performance. The addressed controller design problem is transformed to an auxiliary convex optimization problem, which can be solved by a linear matrix inequality approach. Three examples are provided to illustrate the applicability and less conservativeness of the developed theoretical results. It is easy to see that our approach is simple but our results are much less conservative than the recently published results. Copyright © 2010 John Wiley & Sons, Ltd.
Synthesis, structural, electrochemical, and photophysical properties of 4,2′‐thiopyrylogens – a novel class of sensitizers for photoinduced electron transfer reactions
Authors: Warrier Ajaya Kumar Sankara , Clennan Edward L.
Published: June 2010

The first three examples of the thioanalog of the 4,2′‐pyrylogen ring system are reported. The influence of the sulfur atom on the structural, electrochemical, and photophysical behavior of this ring system is discussed. In addition, these 4,2′‐thiopyrylogens are compared to their previously reported 4,4′‐isomers and their 4,4′‐ and 4,2′‐oxygen analogs. Copyright © 2010 John Wiley & Sons, Ltd.
Remote sensing and field‐based mapping of permafrost distribution along the Alaska Highway corridor, interior Alaska
Authors: Panda Santosh K. , Prakash Anupma , Solie Diana N. , Romanovsky Vladimir E. , Jorgenson M. Torre
Published: June 2010

We employed an integrated approach that combined remote sensing techniques with field measurements to predict the presence/absence of near‐surface permafrost in a section of the Alaska Highway corridor. We investigated the correlative relationships among vegetation type, topography, moss thickness, tussock condition and near‐surface permafrost in the study area. Analysis of moss thickness and active‐layer depth in low‐lying plains (slope <8°) showed an inverse relationship in different vegetation classes. The maximum likelihood classification of remotely sensed data mapped 80% of the study area as covered with vegetation. We developed an empirical‐statistical (Binary Logistic Regression) model to establish the statistical relationship between surface variables and permafrost. The statistical relationships between the surface variables (vegetation, aspect and elevation classes) and permafrost were used within a spatial model to estimate the probability of permafrost presence at any given location (or pixel) in the study area. The statistical model yielded an overall classification accuracy of 80%. The spatial model mapped 62% of the total vegetated area as underlain by permafrost, including 99.5% of the scattered short spruce, 92.5% of the dense tall spruce, and 35.8% of the mixed spruce and deciduous vegetation classes. Comparison of our probabilistic permafrost map with an independently produced photo‐interpreted permafrost map showed 75% agreement for the continuously frozen class and very close agreement for the discontinuously frozen class. Copyright © 2010 John Wiley & Sons, Ltd.
Small gain problem in coupled differential‐difference equations, time‐varying delays, and direct Lyapunov method
Authors: Gu Keqin , Zhang Yashun , Xu Shengyuan
Published: June 2010

This article presents a Lyapunov–Krasovskii formulation of scaled small gain problem for systems described by coupled differential‐difference equations. This problem includes H∞ problem with block‐diagonal uncertainty as a special case. A discretization may be applied to reduce the conditions into linear matrix inequalities. As an application, the stability problem of systems with time‐varying delays is transformed into the scaled small gain problem through a process of either one‐term approximation or two‐term approximation. The cases of time‐varying delays with and without derivative upper‐bound are compared. Finally, it is shown that similar conditions can also be obtained by a direct Lyapunov–Krasovskii functional method for coupled differential‐functional equations. Numerical examples are presented to illustrate the effectiveness of the method in tackling systems with time‐varying delays. Copyright © 2010 John Wiley & Sons, Ltd.