bluuebunny/crossref_metadata_2025_split huggingface dataset:
A plea for more careful presentation of near‐surface air temperature data in geomorphology
Authors: Holden Joseph 
Published: June 2007

AbstractGeomorphologists often provide near‐surface air temperature data for their study sites in publications. This is usually in the form of mean annual or monthly temperature. Inspection of papers in Earth Surface Processes and Landforms for 2004, 2005 and 2006 has shown that the source of these data is usually not given. Problems arise because scientists derive ‘mean temperature’ in different ways, which do not give the same result. It is suggested that a protocol is followed when presenting near‐surface air temperature data for journal publication as part of site descriptions or results. Copyright © 2007 John Wiley & Sons, Ltd.
Recent behaviour of the Debeli Namet glacier, Durmitor, Montenegro
Authors: Hughes Philip. D. 
Published: June 2007

AbstractA small cirque glacier is present in a north‐east facing cirque on the mountain of Šljeme (2455 m a.s.l.) in the Durmitor massif, Montenegro. Sediment ridges in front of this glacier are interpreted as moraines and can be attributed to recent glacier activity over the past 130 years. Lichenometry was applied to determine the relative ages of different moraines using Aspicilia calcarea agg. One set of moraines dates from about 1878 AD, whilst another set of inner moraines dates from about 1904 AD. The most recent moraines appear to have formed within the last 11 years in front of an active glacier margin. Copyright © 2007 John Wiley & Sons, Ltd.
Bank permeability in an Australian ephemeral dry‐land stream: variation with stage resulting from mud deposition and sediment clogging
Authors: Dunkerley David L. 
Published: June 2007

AbstractPercolation of flood waters into the bed and banks of ephemeral streams provides one of the key mechanisms responsible for transmission loss. However, there are very few published estimates of the rates at which water can enter stream‐bank sediments, and little is known about the variation in bank permeability with elevation above the bed and the resulting effects on transmission loss in floods of different magnitudes. This paper presents the results of 69 field determinations of bank infiltrability made on Fowlers Creek, an ephemeral dry‐land stream located in arid western New South Wales, Australia. Fowlers Creek carries high concentrations of suspended sediments, which are deposited as mud drapes on the bed, banks and floodplain. Results demonstrate that infiltration rates are lowest at the base of the banks, and tend to increase steadily with elevation on the bank, even above the apparent upper limit of mud drapes. In parallel, the texture of the bank sediments (assessed from samples of the uppermost 10 cm) becomes coarser with elevation above the bed. This pattern is inferred to relate to the delivery of silts and clays into pore spaces in the bank sediments by percolating flood waters. The patterns of infiltration rate and sediment texture mapped in the field are reasoned to be the product of many clogging episodes in past flood events having different peak stages. The increase in infiltration rate and mean particle size up the banks reflects lower frequencies of submergence and clogging of the upper banks by large floods, and more frequent inundation and clogging of the lower banks by sub‐bank‐full flows. The stage‐related changes in bank permeability provide a mechanism that can drive variations in transmission loss among floods having different peak stages and hydrograph shapes. Copyright © 2007 John Wiley & Sons, Ltd.
Enhanced opportunistic beamforming scheme for practical broadcast systems
Authors: Bosisio R. , Vicario J. L. , Spagnolini U. , Anton‐Haro C. 
Published: June 2007

AbstractIn multiantenna systems the optimisation of linear spatial precoding is severely hampered by the amount of feedback. A practical solution consists in the opportunistic beamforming (OB), which randomly generates the beamforming and schedules the user with the largest signal‐to‐noise ratio (SNR). In this paper we investigate the benefits that can be provided by the knowledge of the users spatial covariance at the transmitter. We enhance the OB scheme by matching the beamforming generation to the users channels spatial patterns. We analytically assess the performance of the proposed scheme, referred to as Cluster‐Eigenbeamforming (Cluster‐EB), both in ideal (perfect feedback) and in practical scenario (imperfect feedback). Cluster‐EB is shown to outperform the conventional schemes and the performance gain increases in practical systems as Cluster‐EB capitalises on the spatial covariance knowledge to reduce the sensitivity with respect to the feedback imperfections. Copyright © 2007 John Wiley & Sons, Ltd.
A sustainability assessment of a health equity fund initiative in Cambodia
Authors: Jacobs Bart , Price Neil , Sam Sam Oeun 
Published: June 2007

AbstractAll but one of the health equity funds (HEFs) currently operating in Cambodia, introduced to address the adverse effects of low user fee exemption rates, rely heavily on external funding and have high administrative overheads. This article reports on a study of one type of HEF, based in Kirivong Operational Health District (KOD) and operated through local pagoda structures, which demonstrates minimal reliance on external funding and low administrative overheads. We utilize an adapted sustainability assessment framework to assess the ability of pagoda structures to enable financial access for the poorest to public sector health services. We further analyse the strengths and limitations of the pagoda‐managed equity fund initiative, with a view to assessing not only its sustainability but its potential for replication in other settings.Our study shows that, against key sustainability indicators (health service utilization and health outcomes; management capacity and financial viability; community mobilization and government support), the pagoda‐managed equity fund initiative scores well. However, it is evident that some external financial support is needed to allow the HEFs to function effectively. We conclude with recommendations for replicating the initiative, which include working innovatively with indigenous grassroots organizations to enhance community HEF ownership and to keep administrative overheads low. Copyright © 2007 John Wiley & Sons, Ltd.
Secret image transmission based on VQ and data embedding
Authors: Shie Shih‐Chieh , Lin Shinfeng D. 
Published: June 2007

AbstractA new secret image transmission scheme suitable for narrow communication channel is proposed in this article. A set of secret images can be simultaneously and efficiently delivered to the receiver via a small and meaningless data stream by the proposed scheme. To reduce the volume of secret images, a codebook is first generated and these secret images are encoded into binary indexes based on the vector quantization (VQ) technique. The compressed message is then embedded into the VQ codebook utilized in the encoding procedure by an adaptive least‐significant‐bits (LSB) modification technique. For the purpose of security, the slightly modified codebook is further encrypted into a meaningless data stream by the AES cryptosystem. Simulation results show that the proposed scheme provides an impressive improvement both in the visual quality of the extracted secret images at the receiver and in the hiding capacity of the cover medium. Experimental data also reveal the feasibility of the proposed secret image transmission scheme for limited‐bandwidth environment. © 2007 Wiley Periodicals, Inc. Int J Imaging Syst Technol, 17, 1–9, 2007
A new automated delineation method for SPECT lung scans using adaptive dual‐exponential thresholding
Authors: Wang Alex , Yan Hong 
Published: June 2007

AbstractAn accurate method for delineating lung contours in single photon emission computed tomography (SPECT) is critical to respiratory studies such as pulmonary embolism (PE) and respiratory aerosol deposition. Current delineation methods are not adaptive in nature and may require a priori information on lung volumes. We have developed a dual‐exponential thresholding method that solely requires SPECT scans, and is fast, accurate, and adaptive in nature. A dataset consisted of 90 patients was studied retrospectively. While most were suspected of PE, other pulmonary disorders were also present. SPECT ventilation scans were obtained after inhalation of ∼40 MBq of 99mTc‐Technegas. Examination of the corresponding natural logarithmically transformed histograms revealed dual exponential functions like pattern. Adaptive thresholds were found as the intercept between the two exponential functions. 350 Monte Carlo simulations representative of normally‐ventilated scans with varying counts were used to quantitatively measure and evaluate the method. Our method correctly delineated lung volumes to above 97% agreement for 310 of the 350 Monte Carlo simulations with maximum count values greater than or equal to 31. The 40 low‐count simulations were included purely as extreme cases. For real patient scenario, an experienced physician was called upon to visually delineate a sample of 50 actual patient scans, and these delineated lung volumes were used as gold standard and compared with those delineated using our method. Our results had an average of 96% agreement. © 2007 Wiley Periodicals, Inc. Int J Imaging Syst Technol, 17, 22–27, 2007
User‐friendly image sharing using polynomials with different primes
Authors: Yang Ching‐Nung , Yu Kun‐Hsuan , Lukac Rastislav 
Published: June 2007

AbstractRecently, Thien and Lin proposed a user‐friendly (k, n)‐threshold scheme which employs Lagrange interpolation to produce shadow images representing a shrunken version of the original image. In this paper, we introduce a new framework which uses more (k − 1)‐degree polynomials with different primes to enhance the functionality of the user‐friendly (k, n)‐threshold framework and obtain more effective performance for large k. Since the proposed framework significantly reduces reconstruction errors compared to the previously published user‐friendly schemes, it is suitable for modern visual communication applications where features such as distributed trust, secure transmission and storage, fault tolerance, and high‐quality image reconstruction are required. © 2007 Wiley Periodicals, Inc. Int J Imaging Syst Technol, 17, 40–47, 2007
Cadmium accumulation and binding characteristics in intact Sertoli/germ cell units, and associated effects on stage‐specific functions in vitro: insights from a shark testis model
Authors: McClusky Leon M. 
Published: June 2007

AbstractThe increased human use of cadmium (Cd) and its increased occurrence in the environment is of concern. The testis is sensitive to Cd because of the steroid‐mediated regulation of spermatogenesis, high levels of DNA synthesis and gene transcription, all of which varies in a stage‐related manner. Validated techniques (acridine orange vital staining to detect apoptosis and dextran‐rhodamine exclusion to assess blood–testis barrier function) were recently developed and the shark testis was proposed as an alternative model for assessing stage‐specific functions in living testicular tissue and to study toxicant actions on spermatogenesis. The present paper shows that 109Cd accumulation and binding in vitro was stage‐dependent (premeiotic, PrM > meiotic, M > postmeiotic, PoM), rapid and persisted in spermatocysts (intact germ cell/Sertoli cell units) 49 h after washout. In competitive binding analyses of all three spermatocyst stages, Hg, but not Zn, could replace bound 109Cd, suggesting that Cd binding was specific. These findings were associated with a biphasic apoptotic response in the PrM spermatocysts, which was maximal at 10 µm CdCl2 and 1 µm CdCl2 after 2 and 4 days in culture, respectively. Although Cd uptake in PoM cysts was more than 2‐fold less than uptake in PrM cysts, the percentage dextran‐rhodamine permeant PoM cysts was ∼8‐fold greater than in controls in the presence of both 10 µm CdCl2 and 30 µm CdCl2 after 4 days culture, indicating that blood–testis barrier function in PoM spermatocysts was compromised. These findings demonstrate that this model has utility for use in screening assays of environmental toxicants. Copyright © 2007 John Wiley & Sons, Ltd.
Antibiotic multiresistance strictly associated with IS256 and ica genes in Staphylococcus epidermidis strains from implant orthopedic infections
Authors: Montanaro Lucio , Campoccia Davide , Pirini Valter , Ravaioli Stefano , Otto Michael , Arciola Carla Renata 
Published: June 2007

AbstractIn this study the presence both of the ica genes, encoding for biofilm exopolysaccharide production, and the insertion sequence IS256, a mobile element frequently associated to transposons, was investigated in relationship with the prevalence of antibiotic resistance among Staphylococcus epidermidis strains. The investigation was conducted on 70 clinical isolates derived from orthopedic implant infections. Among the clinical isolates investigated a dramatic high level of association was found between the presence of ica genes as well as of IS256 and multiple‐resistance to all the antibiotics tested (oxacillin, penicillin, gentamicin, erythromycin, clindamycin, chloramphenicol, sulfamethoxazole + trimethoprim, ciprofloxacin, vancomycin). Noteworthy, a striking full association between the presence of IS256 and resistance to gentamicin was found, being none of the IS256‐negative strain resistant to this antibiotic. This association is probably because of the link of the corresponding aminoglycoside‐resistance genes, and IS256, often co‐existing within the same staphylococcal transposon. In conclusion, in orthopedics, the presence of ica genes and that of IS256 in S. epidermidis genome should both be considered as informative markers of clinically relevant strains equipped with greatest and broadest resistance potential to survive to medical treatments. © 2007 Wiley Periodicals, Inc. J Biomed Mater Res, 2007
Effect of acidic degradation products of poly(lactic‐co‐glycolic)acid on the apatite‐forming ability of poly(lactic‐co‐glycolic)acid‐siloxane nanohybrid material
Authors: Rhee Sang‐Hoon , Lee Seung Jin 
Published: June 2007

AbstractThe effect of poly(lactic‐co‐glycolic) acid (PLGA) degradation products on the apatite‐forming ability of a PLGA‐siloxane nanohybrid material were investigated. Two PLGA copolymer compositions with low and high degradability were used in the experiment. The PLGA‐siloxane nanohybrid materials were synthesized by end‐capping PLGA with acid end‐groups using 3‐isocyanatopropyl triethoxysilane following the sol–gel reaction with calcium nitrate tetrahydrate. Two nanohybrid materials that had different degradability were exposed to simulated body fluid (SBF) for 1–28 days at 36.5°C. The low degradable PLGA hybrid showed apatite‐forming ability within 3 days of incubation while the high degradable one did not within 28 days testing period. The results were explained in terms of the acidity of the PLGA degradation products, which could directly influence on the apatite dissolution. © 2007 Wiley Periodicals, Inc. J Biomed Mater Res, 2007
Influence of hydroxyl content on selected properties of 45S5 bioactive glass
Authors: Hall Matthew M. 
Published: June 2007

AbstractNumerous material properties may be influenced by the concentration of chemically dissolved hydroxyl species within a glass. A tube furnace connected to a steam generator was used to create hydroxyl‐saturated 45S5 glass under 1 atm of water at 1100°C. Selected properties of as‐melted and hydroxyl‐saturated samples were compared to assess the sensitivity of 45S5 to excess hydroxylation. The glass transition temperature and the peak crystallization temperature of the treated 45S5 glass were reduced in comparison to the as‐melted 45S5 glass. In addition, the treated glass exhibited a broad endothermic signal that may be indicative of enhanced viscous flow. A simple dissolution experiment indicated that the treated 45S5 glass was also less durable than the as‐melted 45S5 glass. © 2007 Wiley Periodicals, Inc. J Biomed Mater Res, 2007
Structure, depolymerization, and cytocompatibility evaluation of glycol chitosan
Authors: Knight Darryl K. , Shapka Stephen N. , Amsden Brian G. 
Published: June 2007

AbstractGlycol chitosan, a water soluble chitosan derivative being investigated as a new biomaterial, was fractionated via two different methods. Initial characterization of the glycol chitosan with 1H NMR spectroscopy illustrated the presence of both secondary and tertiary amine groups, contradictory to its widely accepted structure. Fractionation of glycol chitosan with nitrous acid resulted in a significant reduction in the number average molecular weight, specifically, from 170 to ∼7 kDa for a pH 3 and below. However, the reaction altered its chemical structure, as the secondary amine groups were converted to N‐nitrosamines, which are potentially carcinogenic. An increase in the pH of the reaction limited this formation, but not entirely. Free radical degradation initiated with potassium persulfate was not as effective at reducing the molecular weight as the nitrous acid approach, yielding molecular weights around 12 kDa under the same molar ratio of degrading species, but did retain the structural integrity of the glycol chitosan. Additionally, control of the molecular weight appears feasible with potassium persulfate. When assessed in vitro for cytocompatibility, the polymer exhibited no toxicity on monolayer‐cultured chondrocytes, and in fact stimulated cell growth at low concentrations. © 2007 Wiley Periodicals, Inc. J Biomed Mater Res, 2007
Quick‐forming hydroxyapatite/agarose gel composites induce bone regeneration
Authors: Watanabe Junji , Kashii Masafumi , Hirao Makoto , Oka Kunihiro , Sugamoto Kazuomi , Yoshikawa Hideki , Akashi Mitsuru 
Published: June 2007

AbstractWe investigated the fundamental properties of quick‐forming hydroxyapatite (HAp)/agarose gel composites, and evaluated their potential as an injectable bone substitute. From scanning electron microscope observations, the HAp/agarose gel composites produced by an innovative electrophoretic process showed an interconnecting structure with the HAp particles. The diameter of the HAp particles was roughly 1 μm, and the total amount of HAp particles was estimated by a quantification of the calcium ions. In the case of 1 mg of dry composite, 10 μg of HAp was formed in the agarose gel. Moreover, X‐ray diffraction analysis revealed that the HAp particles had an amorphous structure, so the HAp particles were expected to dissolve under physiological conditions relative to the HAp with higher crystallinity. The advantages of the resultant HAp/agarose gel composites are ease of handling, close contact with the surrounding tissues, and ease of use as an injectable material. As a preliminary animal study, the composites were implanted into the medial femoral condyle of rabbits. After implantation, the process of bone regeneration was evaluated by microfocus‐computed tomography (μCT) and histological analysis. At 2 weeks postoperatively, newly‐formed bone was observed at the edge of the bone defect site, and at 4 weeks postoperatively, excellent bone regeneration was observed. The implanted composite gradually degraded, and disappeared at 8 weeks postoperatively. This result indicated that the composite dissolved rapidly, and was replaced by newly‐formed bone. Quick‐forming HAp/agarose gel composites may be a good candidate as an injectable biomaterial, particularly in the fields of orthopedic, oral, and maxillofacial surgery. © 2007 Wiley Periodicals, Inc. J Biomed Mater Res, 2007
The most widespread desmosomal cadherin, desmoglein 2, is a novel target of caspase 3‐mediated apoptotic machinery
Authors: Cirillo Nicola , Lanza Michele , De Rosa Alfredo , Cammarota Marcella , La Gatta Annalisa , Gombos Fernando , Lanza Alessandro 
Published: June 2007

AbstractApoptotic cells are known to regulate the ordered dismantling of intercellular contacts through caspase activity. Despite the important role of desmoglein (Dsg) 2 in epithelial cell–cell adhesion, the fate of this widespread desmosomal cadherin during apoptosis is yet poorly understood. Here, by means of pharmacological approaches, we investigated whether Dsg2 was targeted by caspases in HaCaT and HT‐29 cell lines undergoing staurosporine (STS)‐induced apoptosis. Results showed that STS induced a caspase‐dependent form of cell‐death in both keratinocytes (HaCaT) and enterocytes (HT‐29), that associated with progressive depletion of Dsg2 from cell lysates. The proteolytic processing of full‐length Dsg2 resulted in the appearance of a 70‐kDa fragment which was released into the cytosol. Consistently, immunofluorescence studies revealed that Dsg2 staining was abolished from cell surface whereas the cytoplasmic region of Dsg2 did localize intracellularly. Plakoglobin (Pg) also underwent cleavage and detached from Dsg2. Apoptotic changes paralleled with progressive loss of intercellular adhesion strength. All these biochemical, morphological, and functional changes were regulated by caspase 3. Indeed, in the presence of the caspase 3‐inhibitor z‐DEVD‐fmk, full‐length Dsg2 protein levels were preserved, whereas the amount of the 70‐kDa fragment was maintained on control levels. Furthermore, cells pretreated with z‐DEVD‐fmk retained the membrane labeling of Dsg2. Taken together, our data demonstrate that the apoptotic processing of Dsg2 is mediated by caspase 3 in epithelial cells. J. Cell. Biochem. 103: 598–606, 2008. © 2007 Wiley‐Liss, Inc.
Ab initio study of electronic structure and optical properties of heavy‐metal azides: TlN3, AgN3, and CuN3
Authors: Zhu Weihua , Xiao Heming 
Published: June 2007

AbstractDetailed ab initio studies on the electronic structure and optical properties of the heavy‐metal azides have been performed using density functional theory within the generalized gradient approximation. An analysis of band structure, density of states, charge transfer, and bond order shows that the heavy‐metal azides are ionic compounds but have covalent character. The valence bands of AgN3 and CuN3 are strongly dominated by Ag‐ and Cu‐d, respectively, but that of TlN3 arises from the contributions of Tl‐s and terminal N‐p and not from Tl‐d. The real and imaginary parts of the dielectric function, adsorption coefficient, and electron energy‐loss spectra are calculated and compared with available experimental data. © 2007 Wiley Periodicals, Inc. J Comput Chem, 2008
Symmetry operation measures
Authors: Pinsky Mark , Casanova David , Alemany Pere , Alvarez Santiago , Avnir David , Dryzun Chaim , Kizner Ziv , Sterkin Alexander 
Published: June 2007

AbstractWe introduce a new mathematical tool for quantifying the symmetry contents of molecular structures: the Symmetry Operation Measures. In this approach, we measure the minimal distance between a given structure and the structure which is obtained after applying a selected symmetry operation on it. If the given operation is a true symmetry operation for the structure, this distance is zero; otherwise it gives an indication of how different the transformed structure is from the original one. Specifically, we provide analytical solutions for measures of all the improper rotations, S, including mirror symmetry and inversion, as well as for all pure rotations, C. These measures provide information complementary to the Continuous Symmetry Measures (CSM) that evaluate the distance between a given structure and the nearest structure which belongs to a selected symmetry point‐group. © 2007 Wiley Periodicals, Inc. J Comput Chem, 2008