bluuebunny/crossref_metadata_2025 huggingface dataset:
Modelling reach‐scale variability in sediment mobility: An approach for within‐reach prioritization of river rehabilitation works
Authors: Hoyle J. , Brooks A. , Spencer J.
Published: December 2010

Many Australian river ecosystems have been, and continue to be, adversely affected by increased channel dimensions and sediment supplies occurring in the period since European settlement. One of the key aims of river rehabilitation in these rivers is to help reduce sediment yield by preventing ongoing bank erosion and remobilization of instream bed material stores. While various tools have been developed to help identify sediment sources at the catchment scale, this is often at a resolution that is too coarse to be translated directly to on‐ground rehabilitation works, as most riverworks programs are designed and implemented at the reach or within‐reach scale. This paper provides a method of prioritizing rehabilitation at the within‐reach scale by using a high‐resolution reach‐scale modelling approach to examine the relative entrainment potential of sediment stores. The method has been developed for a 10 km reach of the upper Hunter River, NSW, Australia. Shear stress distribution is examined using the widely available model HEC‐RAS, and incorporating a detailed, LiDAR‐derived, representation of the in‐channel vegetation into a spatially distributed Manning's roughness layer. At the geomorphic unit scale, the results highlight that the elevated ‘bench’ units, which represent significant stores of sand and silt, are much more vulnerable to remobilization than the lower elevation gravel bar units. At the sub‐reach scale (500–2000 m) shear stresses are greatest in the most confined sections. While instream geomorphic heterogeneity has been significantly reduced in these locations, ongoing erosion is limited by bedrock and buried coarse gravel terrace material in the bed and banks. These results highlight the need for targeted rehabilitation strategies that account for within‐reach variability in entrainment potential as well as on‐the‐ground knowledge of sediment supply and geological controls. Copyright © 2010 John Wiley & Sons, Ltd.
Cryptosystems based on continued fractions
Authors: Kanso Ali
Published: December 2010

In this paper, we propose three secret‐key cryptosystems based on the theory of continued fractions for possible use in cryptographic applications. We present and analyze a sequence of rational numbers, whose randomness properties are demonstrated using well‐know statistical packages. Accordingly, we propose a cryptosystem that acts on a group of characters at a time. Then, a binary keystream generator, generating keystreams with good randomness properties, is suggested for possible use in stream cipher applications. Finally, we propose a cryptosystem related to the well‐known Baptista's cryptosystem that is based on a chaotic logistic map. However, our cryptosystem is based on the theory of continued fractions, and is shown to exhibit better properties and decrypts information much faster than Baptista's cryptosystem. Copyright © 2010 John Wiley & Sons, Ltd.
Network specific false alarm reduction in intrusion detection system
Authors: Hubballi Neminath , Biswas Santosh , Nandi Sukumar
Published: December 2010

Intrusion Detection Systems (IDSs) are used to find the security violations in computer networks. Usually IDSs produce a vast number of alarms that include a large percentage of false alarms. One of the main reason for such false alarm generation is that, in most cases IDSs are run with default set of signatures. In this paper, a scheme for network specific false alarm reduction in IDS is proposed. A threat profile of the network is created and IDS generated alarms are correlated using neural network. Experiments conducted in a test bed have successfully filtered out most of the false alarms for a range of attacks yet maintaining theDetection Rate. Copyright © 2010 John Wiley & Sons, Ltd.
Optimized packet formation in multi‐level security wireless data acquisition networks
Authors: Younis Mohamed , Farrag Osama , Lee Sookyoung , D'Amico William
Published: December 2010

The limited channel capacity and the varying propagation conditions of radio signals have motivated research for boosting the achievable throughput in wireless networks. Among the effective optimization strategies is to dynamically adjust the packet size either to better suit the channel conditions or to minimize the number of overhead bits in the individual packets. However, multi‐levels of security requirements impose constraints on the data mix in the packet payload and may diminish the gains achievable by contemporary packet‐size optimization schemes. This paper presents a novel bandwidth optimization algorithm for wireless data acquisition networks where strict confidentiality requirements and access restriction policies have to be observed. The algorithm exploits the classification of data in minimizing the number of packet transmissions as well as the overhead within the individual packets. The idea is to combine the transmission of packets based on the time sensitivity and security attributes of the data in the payload. The performance of the proposed algorithm is validated through mathematical analysis and through simulation. The simulation results confirm the effectiveness of the algorithm in boosting data throughput in the network. Copyright © 2010 John Wiley & Sons, Ltd.
Repair of post‐tensioned precast beam to column connections
Authors: Kaya Mustafa , Arslan A. Samet
Published: December 2010

Earthquakes can cause immense damage to precast structures, rendering them inhabitable. After the 1999 Marmara earthquake in Turkey, research by the Turkish Precast Union stated that 24.50% of the precast structures were damaged with some of this damage being observed in the beam‐to‐column connections of the structures. Since it is essential to provide those rendered homeless by the earthquake with safe habitable accommodation, repairing medium and slight levels of damage at the connection parts should be undertaken. In order to prove that a repaired connection was sufficiently strong, a precast beam‐to‐column post‐tensioned connection was tested in three phases. In phase one, middle level damage was observed at 6% drift at these connections. In phase two, 1.2, 2.4 and 4.8% drifts were applied three times to the test specimens. As a result of the extra loads applied, little damage was observed. In the last phase, the four connections tested in the first phase were repaired using epoxy resin and then retested. The results from the tests on the repaired precast and the reference undamaged specimens showed that the repaired specimens were sufficiently strong, thus proving that repair to damaged precast beam‐to‐column post‐tensioned connections can be undertaken. Copyright © 2010 John Wiley & Sons, Ltd.
Theoretical design of high‐performance microstrip ultra‐wideband bandpass filters with controllable transmission zeros
Authors: Chen Chun‐Ping , Ma Zhewang , Anada Tetsuo , Hsu Jui‐Pang
Published: December 2010

This paper presents an efficient design of high‐performance microstrip ultra‐wideband (UWB) bandpass filters (BPFs) consisting of stepped‐impedance resonators (SIRs) and two‐section open‐ended SIR stubs. An analytical study is conducted on the proposed filter prototype to show its theoretical mechanism when an exact elliptical function synthesis technique is not available. Instead, a pseudo‐elliptical filter design scheme is successfully proposed for filter. As an example, a UWB BPF with a fractional bandwidth (FBW) of 110% (BW: 3.1–10.6 GHz) is then synthesized, simulated, fabricated, and measured. The measured frequency responses of the UWB filter compare very well with the predicted ones and successfully satisfy the outdoor specifications of the Federal Communications Commission (FCC). The fabricated filter also exhibits an easily fabricated structure (no via holes and a minimum gap size of 0.16 mm), a compact size, low insertion loss, a flat group delay, and good stopband characteristics as well. It should be noted that, in terms of the proposed design scheme, the proposed filter prototype can also be used to realize a UWB filter with a given FBW of even greater than 110%. © 2010 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.
One‐dimensional Salen‐type Chain‐like Lanthanide(III) Coordination Polymers: Syntheses, Crystal Structures, and Fluorescence Properties
Authors: Wang Gui‐Ling , Tian Yong‐Mei , Cao Dian‐Xue , Yu Yan‐Shuang , Sun Wen‐Bin
Published: December 2010

Four salen‐type lanthanide(III) coordination polymers [LnH2L(NO3)3(MeOH)x]n [Ln = La (1), Ce (2), Sm (3), Gd (4)] were prepared by reaction of Ln(NO3)3·6H2O with H2L [H2L = N,N′‐bis(salicylidene)‐1,2‐cyclohexanediamine]. Single‐crystal X‐ray diffraction analysis revealed that H2L effectively functions as a bridging ligand forming a series of 1D chain‐like polymers. The solid‐state fluorescence spectra of polymers 1 and 2 emit single ligand‐centered green fluorescence, whereas 3 exhibits typical red fluorescence of SmIII ions. The lowest triplet level of ligand H2L was calculated on the basis of the phosphorescence spectrum of GdIII complex 4. The energy transfer mechanisms in the lanthanide polymers were described and discussed.
Therapeutic role of direct peroral cholangioscopy using an ultra‐slim upper endoscope
Authors: Moon Jong Ho , Choi Hyun Jong , Ko Bong Min
Published: December 2010

Introduction

Peroral cholangioscopy provides direct visualization of the bile duct and facilitates diagnostic procedures and therapeutic intervention. The currently available mother–baby scope system is not widely used because of its disadvantages. Direct peroral cholangioscopy (POC) with a regular, ultra‐slim, upper endoscope can provide a valuable and economic solution for evaluating bile duct lesions, although its therapeutic role in biliary tract disease is uncertain. We assessed the usefulness of direct POC with an ultra‐slim endoscope for therapeutic application in patients with biliary diseases.

Methods

Several new techniques and accessories allow therapeutic intervention under direct POC using an ultra‐slim upper endoscope with a larger, 2‐mm working channel. Intracorporeal laser or electrohydraulic lithotripsy under direct POC is a main therapeutic intervention for patients with bile duct stones resistant to conventional endoscopic procedures. Tumor ablation therapy such as photodynamic therapy and argon plasma coagulation may be performed under direct POC. Direct POC can be applied to guide biliary interventions such as guidewire placement, stone removal, and migrated stent retrieval, using diverse accessories.

Conclusion

Direct POC with an ultra‐slim upper endoscope allows therapeutic intervention for patients with biliary diseases. Enhancements of the endoscope and specialized accessories are expected to expand the therapeutic role of direct POC.
Increasing DHA and EPA Concentrations Prolong Action Potential Durations and Reduce Transient Outward Potassium Currents in Rat Ventricular Myocytes
Authors: Li Hong‐Xia , Wang Ru‐Xing , Li Xiao‐Rong , Guo Tao , Wu Ying , Guo Su‐Xia , Sun Li‐Ping , Yang Zhen‐Yu , Yang Xiang‐Jun , Jiang Wen‐Ping
Published: December 2010

The goal of this study was to determine the mechanisms of n‐3 polyunsaturated fatty acids (n‐3 PUFA) on anti‐arrhythmias and prevention of sudden death. The calcium‐tolerant Sprague–Dawley rat ventricular myocytes were isolated by enzyme digestion. Effects of docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA) on action potentials and transient outward potassium currents (Ito) of epicardial ventricular myocytes were investigated using whole‐cell patch clamp techniques. Action potential durations (APDs) andItowere observed in different concentrations of DHA and EPA. APD25, APD50, and APD90with 0.1 μmol/L DHA and EPA were prolonged less than 15% and 10%. However, APDs were prolonged in concentration‐dependent manners when DHA and EPA were more than 1 μmol/L. APD25, APD50, and APD90were 7.7 ± 2.0, 21.2 ± 3.5, and 100.1 ± 9.8 ms respectively with 10 μmol/L DHA, and 7.2 ± 2.5, 12.8 ± 4.2, and 70.5 ± 10.7 ms respectively with 10 μmol/L EPA.Itocurrents were gradually reduced with the increased concentrations of DHA and EPA from 1 to 100 μmol/L, and their half‐inhibited concentrations were 2.3 ± 0.2 and 3.8 ± 0.6 μmol/L. The results showed APDs were prolonged andItocurrent densities were gradually reduced with the increased concentrations of DHA and EPA. The anti‐arrhythmia mechanisms of n‐3 PUFA are complex, however, the effects of n‐3 PUFA on action potentials andItomay be one of the important mechanisms.
A New Mechanism for Photo‐ and Radiation‐Induced Decomposition of Sphingolipids
Authors: Lisovskaya Alexandra G. , Shadyro Oleg I. , Edimecheva Irina P.
Published: December 2010

Data have been obtained showing regularities in product formation following radiolysis of serinol, lysosphingomyelin and photolysis of N‐(2‐hydroxypropyl)hexanamide, sphingomyelin, which point to the possibility of photo‐ and radiation‐induced destruction of the named substrates via a C–C bond rupture. The key stage of this process is the formation and decomposition of N‐centered radicals generated from the starting compounds.
Antioxidative and hepatoprotective effects of fructo-oligosaccharide ind-galactose-treated Balb/cJ mice
Authors: Chen Hsiao-Ling , Wang Cheng-Hsin , Kuo Yi-Wen , Tsai Chung-Hung
Published: December 2010

Chronic subcutaneous (s.c.) administration ofd-galactose (DG) to BL/6J mice has been shown to induce oxidative stress and is considered a model to mimic accelerated ageing. Fructo-oligosaccharide (FO) is a well-defined prebiotic and its fermentation by lactic acid bacteria has been shown to exert antioxidative capacity. The present study was aimed to determine whether FO attenuated DG-induced oxidative stress and hepatopathy in Balb/cJ mice. Mice (12 weeks of age,n40) were divided into control (s.c. saline), DG (s.c. 1·2 g/kg body weight), DG+FO (5 %, w/w) and DG+vitamin E (0·2 %, w/w) groups and were killed after 52 d of treatment. Results indicated that DG significantly decreased the hepatic superoxide dismutase and glutathione peroxidase activities. These alterations were ameliorated both by FO and vitamin E. DG increased the hepatic TAG content approximately by 7·2 % compared with the vehicle control, which was in agreement with the histological alteration. FO, similar to vitamin E, almost normalised the hepatic TAG content and ameliorated the histological characteristics of fatty liver. Similarly, the increased plasma alanine aminotransferase activity induced by DG was normalised by FO and vitamin E, respectively. Faecal bifidobacteria counts were greater in the DG+FO and DG+vitamin E groups compared with the DG group, respectively. In conclusion, the present study indicated that FO diminished the altered hepatic antioxidative enzyme activities and morphology caused by chronic DG administration in Balb/cJ mice, partially associated with its prebiotic role in the colon.
Diagnosis of intramammary infection in samples yielding negative results or minor pathogens in conventional bacterial culturing
Authors: Bexiga Ricardo , Koskinen Mikko T , Holopainen Jani , Carneiro Carla , Pereira Helena , Ellis Kathryn A , Vilela Cristina L
Published: December 2010

Up to half of quarter milk samples submitted for mastitis diagnosis are culture-negative results or lead to identification of coagulase-negative staphylococci or Corynebacterium bovis in conventional culturing, the so-called minor pathogens. The interpretation and usefulness of these results in terms of udder and animal health management is limited, even though the amount of resources spent is relatively high. This work aimed to test two methods of analysis of milk samples with the goal of increasing detection of intramammary pathogens. In the first study, 783 milk samples were processed in duplicate: before and after freezing at −20°C for 24 h, using standard bacteriological techniques. There was a significant difference between the two methods with samples frozen for 24 h yielding significantly fewer Gram-positive catalase-positive cocci, Gram-negative bacilli, Gram-positive bacilli and significantly more samples leading to no growth, than samples before freezing. The number of samples yielding Gram-positive catalase-negative cocci was not significantly affected by freezing. In the second study, a real-time PCR-based test was performed on milk samples with an individual quarter somatic cell count above 500 000 cells/ml that were either negative (n=51 samples) or that led to the isolation of minor pathogens in culturing: Corynebacterium bovis (n=79 samples) or non-aureus staphylococci (NAS, n=32). A mastitis pathogen, beyond the result obtained with standard bacteriology, was detected on 47% of the no-growth samples, on 35% of the samples from which C. bovis had been isolated and on 25% of the samples from which NAS had been isolated. The most commonly detected major pathogen was Escherichia coli, followed by Streptococcus uberis, Arcanobacterium pyogenes/Peptoniphilus indolicus and Streptococcus dysgalactiae. These results suggest that simply freezing milk samples for 24 h does not increase the detection of intramammary bacteria in milk samples and therefore should not be recommended. However, use of the real-time PCR-based test may be useful in diagnosing intramammary infections when milk samples with high somatic cell counts are culture-negative or when culturing results in the detection of minor pathogens.
Cleaning effectiveness of chlorine-free detergents for use on dairy farms
Authors: Sundberg Martin , Christiansson Anders , Lindahl Cecilia , Wahlund Lotten , Birgersson Carol
Published: December 2010

A method for evaluating cleaning effect based on Bacillus cereus spores was developed and tested in a model system designed to resemble actual farm conditions. A test rig with four removable sampling plates was mounted in a milk line. The plates were attached at the end of T-junctions protruding either 1·5 or 3-times the milk pipe diameter from the main loop to reflect different levels of cleaning difficulty. In each cleaning test, B. cereus spores were applied to the four sampling plates to simulate soil. A series of cleaning tests was conducted at 35, 45, 55 and 65°C with six commercial chlorine-free, alkaline detergents; three liquid and three powder-based products. A commercial alkaline detergent with chlorine, a sodium hydroxide solution, a sodium hydroxider/hypochlorite solution and pure water were also tested. Triplicate tests were performed with each cleaning solution, giving a total of 120 cleaning tests. The cleaning effect was evaluated by comparing the number of spores before and after cleaning. At all temperatures, the two chlorine-based cleaning solutions gave significantly greater reductions in B. cereus spores than the chlorine-free products. All six commercial chlorine-free, alkaline detergents generally gave similar cleaning effects, with no differences in the performance of powder-based and liquid forms. The mechanical spore reduction effect with water alone was greater (1·5–1·8 log-units) than the additional chemical effect of sodium hydroxide or chlorine-free detergents (0·5–1·2 log-units). The chlorine-based solutions had a considerably more powerful chemical effect (2–4 log-units depending on temperature). In general, an increase in cleaning solution temperature up to 55°C gave a greater reduction in spores. A further increase to 65°C did not improve cleaning effectiveness.
Differential leucocyte count for ewe milk with low and high somatic cell count
Authors: Albenzio Marzia , Caroprese Mariangela
Published: December 2010

This study was undertaken to compare flow cytometry (FC) and direct microscopic leucocyte count (MDLC) for the differentiation of macrophages, lymphocytes and polymorphonuclear leucocyte (PMN) and to evaluate leucocyte distribution in ewe milk with low and high somatic cell count (SCC). Milk samples were grouped for somatic cell count in low SCC (LSCC) when the content was lower than 5·00×105/ml and high SCC (HSCC) when the content was higher than 1·00×106/ml. No differences were found between the two methods tested suggesting that FC could be used as a routine test for rapid discrimination of leucocytes. Percentages of lymphocytes in ewe milk were higher in LSCC (50%) than in HSCC (39%) and count ranged from 273·91±56·62×103cells/ml (LSCC) to 308·90±46·15×103cells/ml (HSCC). PMN number was lower in LSCC than in HSCC (248·83±46·87×103cells/ml v. 444·38±58·62×103cells/ml); accordingly the percentage was lower in LSCC (40%) than in HSCC (57%). No differences were found for macrophages which were 36·36±5·51×103cells/ml and 39·32±6·83×103cells/ml in LSCC and HSCC, respectively. Lymphocytes in ewe milk did not vary with increased number of somatic cells and were the predominant cell type in LSCC. PMN represented the main population detected in HSCC and the correlation with SCC evidenced that this leucocyte class could be useful in differentiating ewe milk cell count, being strictly responsible for the SCC increase.
Interleukin-6 in quarter milk as a further prediction marker for bovine subclinical mastitis
Authors: Sakemi Yoko , Tamura Yutaka , Hagiwara Katsuro
Published: December 2010

Subclinical mastitis (SM) is a major concern in the dairy industry because it causes economic losses and can lead to clinical mastitis. The mechanisms of the onset and progression of SM are not fully understood, and a new procedure for the detection and appropriate prediction of SM leading to clinical mastitis is necessary for dairy cow management. Inflammatory cytokines such as interleukin (IL)-6 are known to be present in inflamed mammary glands at the onset of mastitis, and IL-6 concentrations correlate with the levels of inflammation. In this study, the detection of IL-6 was examined for the evaluation for the future prediction of SM in 77 quarter milk samples from 20 cows. IL-6 concentrations in quarter milk were measured by sandwich ELISA, and the data were compared with milk somatic cell count (SCC) levels to diagnose SM. Average IL-6 concentration was significantly higher in SM quarter milk (207·0±441·6 pg/ml) than in healthy control quarter milk (12·6±33·4 pg/ml,P<0·01). Results of the cross-tabulation table show that SM prediction accuracy based on IL-6 concentration was almost equal or superior to SM prediction accuracy based on SCC. The detection of IL-6 in milk indicated SM earlier than did the detection of elevated SCC. Thus, the detection of IL-6 in milk could be a future prediction marker for SM.
Family Strategies: Fluidities of Gender, Community and Mobility in Rural West China
Authors: Judd Ellen R.
Published: December 2010

This article queries the current mobility of China's rural population by inverting the usual urban perspective and looking at this mobility through exploring the lives of those who do not move. It departs from a micro-analysis of who remains in the countryside in three west China agricultural communities between 2003 and 2005 and links this with an exploration of emergent structural features of rural communities as they are remade in the early 21st century in the wake of the abolition of agricultural taxes and levies. The ethnographic approach adopted highlights the agency, choices and practices of local people in charting their courses in a rural social world being drained of people. It proposes the utility for analysis of family strategies, identifying a repertoire of resourceful and diverse practices through which people strive to recreate and repopulate their social worlds. The argument links the study of historical directions in polity and economy with local and gendered practices in everyday life.
An Action-Based Approach to Improving Pain Management in Long-Term Care
Authors: Kaasalainen Sharon , Brazil Kevin , Coker Esther , Ploeg Jenny , Martin-Misener Ruth , Donald Faith , DiCenso Alba , Hadjistavropoulos Thomas , Dolovich Lisa , Papaioannou Alexandra , Emili Anna , Burns Tim
Published: December 2010

Objectif : Les objectifs de cette étude étaient double : (1) d’explorer les obstacles à la gestion de la douleur et ceux associés à la mise en œuvre d’un programme de gestion de la douleur en soins de longue durée (SLD) et (2) de développer une approche interprofessionelle afin d’améliorer la gestion de la douleur en soins de longue durée.

Méthodes : Une étude de cas a inclus tous les deux éléments, quantitatifs et qualitatifs. Nous avons recueilli des données sur deux sites LTC à l’aide de sept groupes de discussion pour les infirmières autorisées, fournisseurs de soins non réglementés, et médecins, et 10 entretiens avec des autres groupes de fournisseurs de soins de santé, l’administration et des résidents. Nous avons examiné les documents et administré un sondage à court aux participants à l’étude pour évaluer les perceptions des obstacles à la gestion de la douleur.

Résultats : Les résultats ont révélé des obstacles à la gestion efficace de la douleur au niveau des soins de longue durée des résidents et des familles, des fournisseurs de soins de santé, et des systèmes de santé. Nous avons ensuite élaboré un modèle à six niveaux, avec les interventions proposées pour surmonter ces obstacles.

Conclusions : Ce modèle peut guider le développement d’approches novatrices pour améliorer la gestion de la douleur dans les établissements de soins de longue durée.
Health, Pensions, and the Retirement Decision: Evidence from Canada
Authors: Schirle Tammy
Published: December 2010

En utilisant des données longitudinales de l’Enquête sur la dynamique du travail et du revenu, j’examine les effets de la santé et des régimes de pension offerts par les employeurs sur les décisions de retraite ce qui n’a pas été étudiés simultanément dans le contexte canadien. Les résultats indiquent que les régimes de pension offerts par les employeurs ont des effets incitatifs importants et significatifs sur le comportement de la retraite. Etre en mauvaise santé augmente considérablement la probabilité de prendre sa retraite, jusqu’à 25 points de pourcentage. Les résultats corroborent les résultats antérieures concernant l’importance relative de l’atténuation et le biais de la justification de l’auto-déclaration des mesures de santé. En outre les résultats confirment aussi les conclusions des recherches américains et européens, que l’état de santé et les régimes de pension offerts par les employeurs sont des déterminants importants de la retraite.
Molecular epidemiology and genetic diversity ofCampylobacter jejuniin ruminants
Authors: GROVE-WHITE D. H. , LEATHERBARROW A. J. H. , CRIPPS P. J. , DIGGLE P. J. , FRENCH N. P.
Published: December 2010

Multi-locus sequence typing was performed on 1003Campylobacter jejuniisolates collected in a 2-year longitudinal study of 15 dairy farms and four sheep farms in Lancashire, UK. There was considerable farm-level variation in occurrence and prevalence of clonal complexes (CC). Clonal complexes ST61, ST21, ST403 and ST45 were most prevalent in cattle while in sheep CC ST42, ST21, ST48 and ST52 were most prevalent. CC ST45, a complex previously shown to be more common in summer months in human cases, was more prevalent in summer in our ruminant samples. Gene flow analysis demonstrated a high level of genetic heterogeneity at the within-farm level. Sequence-type diversity was greater in cattle compared to sheep, in cattle at pasturevs. housed, and in isolates from farms on the Pennines compared to the Southern Fylde. Sequence-type diversity was greatest in isolates belonging to CC ST21, ST45 and ST206.
BOY-ORPHANS, MESMERIC VILLAINS, AND FILM STARS: INSCRIBINGOLIVER TWISTINTOTREASURE ISLAND
Authors: Knoepflmacher U. C.
Published: December 2010

Oliver Twist,the early novelwhich a twenty-five-year-old Charles Dickens published serially from 1837 to 1839, revised in the 1840s, and featured in the public readings he offered from 1867 until his death in 1870, might well have inspired the thirty-two-year-old Robert Louis Stevenson before he serialized his own first novel,Treasure Island, in 1882. There are, after all, remarkable similarities between the two texts. For each dramatizes a young boy's immersion in a counter-world headed by villains who defy the norms of a dubious patriarchal order. What is more, the strong spell that thieves like Fagin and Bill Sikes and pirates like Billy Bones and Long John Silver exert over the innocents they mesmerize infects readers of each narrative as well as viewers of their many cinematic adaptations. We thus face a quandary. Despite our empathy with little Oliver and with his adolescent counterpart Jim Hawkins, we may question each boy's reintegration into an order whose fissures have been radically exposed.
ESEM-EDS Investigation of the Weathering of a Heritage Sydney Sandstone
Authors: Ip Kin Hong , Stuart Barbara , Ray Abhi , Thomas Paul
Published: December 2010

The degradation of Sydney sandstone used to build the heritage St Mary's Cathedral in Sydney, Australia, has been investigated using environmental scanning electron microscopy combined with energy dispersive X-ray spectroscopy. This technique provided the structural details of the cementing clay and an elemental characterization the sandstone. The observed differences in the elemental composition of the unweathered and weathered sandstones were associated with changes to the clay microstructure upon weathering. The results support the substitution theory that Fe3+ replaces Al3+ in the kaolinite clay component upon weathering. An examination of the impurities present prior to a nonstructural iron removal treatment revealed the presence of minerals that may provide a source of the elements responsible for the substitution process.
Role of magnetosheath force balance in regulating the dayside reconnection potential
Authors: Lopez R. E. , Bruntz R. , Mitchell E. J. , Wiltberger M. , Lyon J. G. , Merkin V. G.
Published: December 2010

When the interplanetary magnetic field (IMF) is southward, most of the ionospheric potential is generated by merging between the IMF and the magnetospheric field. Typically, the ionospheric potential responds linearly to the magnitude of the southward IMF. However, when the IMF magnitude is large, the ionospheric potential saturates and it becomes relatively insensitive to further increases in the IMF magnitude. We present evidence from simulations that under purely southward IMF conditions, the value of the portion of the potential due to reconnection is controlled by the divergence of the magnetosheath flow, which determines the geoeffective length in the solar wind. Typically, the gradient in the plasma pressure controls the magnetosheath flow, so as the southward IMF increases in magnitude, the change in the magnetosheath force balance is negligible, the geoeffective length in the solar wind does not change, and the reconnection potential increases linearly with the magnitude of the IMF. However, when the IMF magnitude increases to the point where J × B becomes the dominant force in the magnetosheath, further increases in IMF magnitude do affect the overall force balance, diverting more flow away from the merging line, decreasing the geoeffective length, and limiting the global merging rate. Thus magnetosheath force balance can be seen as a single organizing factor that regulates the geoeffective length in the solar wind for the entire range of solar wind parameters.
The Role of porosity evolution and fluid flow in frictional instabilities: A parametric study using a spring‐slider dynamic system
Authors: Mitsui Y. , Cocco M.
Published: December 2010

We have investigated the role of porosity evolution and fluid flow in frictional instabilities by analyzing the response of a single degree of freedom dynamic system. The spring slider is governed by rate‐ and state‐dependent constitutive law. We also account for effective normal stress changes caused by thermal pressurization with constant or variable porosity. Our simulations show that the stress drop during dynamic instabilities depends on constitutive parameters, porosity evolution, fluid flow as well as on the effective fault zone thickness, defined in this study as the ratio between the nominal thickness of the fault zone (w) and the hydraulically activated layer (why). Both porosity evolution and fluid flow can avoid the extremely large stress drop values inferred by thermal pressurization models and provide an attempt to reconcile them with seismological observations.
Comparisons between ion distributions retrieved from ENA images of the ring current and contemporaneous, multipoint ion measurements recorded in situ during the major magnetic storm of 15 May 2005
Authors: Lu L. , McKenna‐Lawlor S. , Barabash S. , Brandt P. C. , Balaz J. , Liu Z. X. , He Z. H. , Reeves G. D.
Published: December 2010

The Neutral Atom Detector Unit (NUADU) aboard the TC‐2 spacecraft recorded energetic neutral atom (ENA) image data for >3 h during part of the main and recovery phases of a major magnetic storm on 15 May 2005. A custom designed, constrained linear inversion method was applied to retrieve ring current ion distributions in the ENA records out to L = 6.6. Comparisons were then made between the ion fluxes retrieved from these ENA data (energy ranges 50–81 keV and 81–158 keV) and complementary, contemporaneous particle fluxes measured in situ by Synchronous Orbit Particle Analyzer (SOPA) instruments aboard a series of geosynchronous satellites that were launched to encircle the equatorial plane at L ∼ 6.6 by the Los Alamos National Laboratory (LANL). The ENA data revealed the development of two emission peaks during the main phase of the storm which corresponded to the arrival from the magnetotail of a pair of particle injections. These injections reached, in each case, maximum value before the corresponding AL index amplitude peak was attained. The main phase of the storm concluded (Dst ≈ −256 nT) in the aftermath of this event pair, and the ring current ion fluxes thereafter gradually decayed over several hours (the storm recovery phase). This is the first time that the linear inversion method developed for NUADU data has been globally validated using multipoint in situ measurements made at different magnetic local times. It was found that the higher the derived flux values were on the duskside/nightside, the closer they were to the in situ measurements. The retrieved fluxes obtained on the duskside/nightside tended, however, to be still somewhat underestimated since the ENA measurements concerned were made around the outer edge of the ring current at an altitude where the magnetic field in the inner magnetosphere deviates from that dipole configuration assumed in the inversion procedure to pertain there. The two methods utilized to study ions during a large magnetic storm are complementary in that the retrieved ion fluxes provide high time resolution information concerning the changing, large‐scale structure of ring current events, whereas in situ flux sampling presents “measurement truth” at particular locations within individual ring currents.
Metapopulation capacity with self-colonization: Finding the best patches in fragmented habitats
Authors: Schnell Jessica , Russell Gareth , Harris Grant , Pimm Stuart
Published: December 2010

Habitat fragmentation continues to be a leading threat for our global future. Methods to quantify fragmentation of habitat landscapes, particularly for endangered species, would be especially useful in conservation planning. Using the principles of metapopulation theory, we updated and devised two methods for analyzing fragmented landscapes: metapopulation capacity and abandonment rate. Our version of metapopulation capacity includes a self-colonization component to counteract the issue metapopulation theory experiences with single large patches. We then tested these methods on satellite image range maps of endemic birds in the highland forests of northern Central America.The metapopulation capacity method proved to be a better measure in that it highlighted which patches would be the most successful habitat in the landscape, based on size and connectivity to surrounding patches, thus allowing for species persistence. Unexpectedly, the abandonment rate method proved useful in providing a way of measuring each individual patch’s support to the rest of the landscape system. This could then be used to rank the remaining patches in order of their greatest contribution. Finally, by using a historical satellite map that showed previously forested habitat in the now deforested landscape, we were able to generate optimal restoration sequences by ranking each 1 km squares’ potential contribution.
Re: Trisomy 21: 91% detection rate using second‐trimester ultrasound markers
Authors: Hutchon D. J. R.
Published: December 2010

Re: Trisomy 21: 91% detection rate using second‐trimester ultrasound markers

D. J. R. Hutchon, Memorial Hospital, Hollyhurst Road, Darlington, County Durham DL3 6HX, UK

Author's reply : G. R. DeVore, Fetal Diagnostic Center, Suite 206, 301 South Fair Oaks Ave, Pasadena, CA, 91105, USA
Nuchal fold thickness at 14–16 weeks' gestation as measured by transvaginal sonography
Authors: Ben‐Ami M. , Perlitz Y. , Mukary M. , Peleg D.
Published: December 2010

Objective

To establish normal values of fetal nuchal fold thick‐ness at 14–16 weeks of gestation by transvaginal sonography.

Methods

Transvaginal sonography was used to measure nuchal fold thickness in 182 normal pregnancies at 14–16 weeks of gestation. Nuchal fold thickness was measured as the distance from the outer skull bone to the outer skin surface in the transverse axial image in the suboccipital‐bregmatic plane of the head.

Results

There was no significant association between nuchal fold thickness and gestational age (r = 0.084; P = 0.258). The mean (standard deviation) was 2.2 (0.5) mm and the 95th centile was 3.0 mm.

Conclusions

The 95th centile of nuchal fold thickness measured by transvaginal sonography at 14–16 weeks is 3.0 mm. Copyright © 2002 ISUOG
Securing special nuclear material: Recent advances in neutron detection and their role in nonproliferation
Authors: Runkle R. C. , Bernstein A. , Vanier P. E.
Published: December 2010

Neutron detection is an integral part of the global effort to prevent the proliferation of special nuclear material (SNM). Applications relying on neutron-detection technology range from traditional nuclear nonproliferation objectives, such as safeguarding material and verifying stockpile reductions, to the interdiction of SNM—a goal that has recently risen in priority to a level on par with traditional missions. Large multinational programs targeting interdiction and safeguards have deployed radiation-detection assets across the globe. In parallel with these deployments of commercially available technology, significant research and development has been directed toward the creation of next-generation assets. Neutron-detection technology plays a prominent role because of the capability of neutrons to penetrate materials that readily absorb gamma rays and the unique fission signatures neutrons possess. One particularly acute technology-development challenge results from dwindling supplies of H3e, partially triggered by widespread deployment of high-efficiency systems for portal monitoring. Other emerging missions, such as the desire to detect SNM at greater standoff distances, have also stimulated neutron-detection technology development. In light of these needs, this manuscript reviews the signatures of neutrons emitted by SNM, the principles of neutron detection, and various strategies under investigation for detection in the context of nuclear nonproliferation.
Acceleration and guiding of fast electrons by a nanobrush target
Authors: Zhao Zongqing , Cao Lihua , Cao Leifeng , Wang Jian , Huang Wenzhong , Jiang Wei , He Yingling , Wu Yuchi , Zhu Bin , Dong Kegong , Ding Yongkun , Zhang Baohan , Gu Yuqiu , Yu M. Y. , He X. T.
Published: December 2010

Laser interaction with a nanobrush target plasma is investigated at the SILEX-I laser facility [X. F. Wei et al., J. Phys. Conf. Ser. 112, 032010 (2008)] with a laser of intensity 7.9×1018 W/cm2. Highly collimated fast electron beams with yields of more than three times higher than that from the planar target can be produced. Two-dimensional particle-in-cell simulation confirms that a layered surface structure can increase the efficiency of laser energy absorption, and the resulting fast electrons are tightly collimated and guided by the plasma layers to a cross section of about the laser spot size.
Viscous elongation of glass rods: Experiments, simulations, and analysis
Authors: Irisawa T. , Cargill G. S. , Hwang K. J. , Maniatty A. M.
Published: December 2010

Viscous elongation of glass rods has been investigated to improve procedures for producing parabolic capillaries from straight capillaries for use as intensity concentrating x-ray optical elements. Experiments and simulations have been carried out pulling Corning 7740 borosilicate glass rods in a cylindrical furnace. Simulations were based on one-dimensional and two-dimensional finite difference/element calculations, assuming that deformation occurred by linear viscous flow and that the temperatures in the glass remained in equilibrium with the temperatures measured along the axis of the furnace. Rates of elongation in experiments were smaller than those in simulations for later stages of the elongation process. Further experimental and analytical investigations ruled out explanations based on increased viscosities caused by structural relaxation or by partial crystallization and showed that the simulations gave incorrect results because they did not incorporate the dependence of local heat transfer processes on the glass rod radius.
Adiabatic description of capture into resonance and surfatron acceleration of charged particles by electromagnetic waves
Authors: Artemyev A. V. , Neishtadt A. I. , Zelenyi L. M. , Vainchtein D. L.
Published: December 2010

We present an analytical and numerical study of the surfatron acceleration of nonrelativistic charged particles by electromagnetic waves. The acceleration is caused by capture of particles into resonance with one of the waves. We investigate capture for systems with one or two waves and provide conditions under which the obtained results can be applied to systems with more than two waves. In the case of a single wave, the once captured particles never leave the resonance and their velocity grows linearly with time. However, if there are two waves in the system, the upper bound of the energy gain may exist and we find the analytical value of that bound. We discuss several generalizations including the relativistic limit, different wave amplitudes, and a wide range of the waves’ wavenumbers. The obtained results are used for qualitative description of some phenomena observed in the Earth’s magnetosphere.
Global regularity for generalized anisotropic Navier–Stokes equations
Authors: Zhang Ting
Published: December 2010

We consider the global Cauchy problem for the three-dimensional generalized anisotropic Navier–Stokes system with the viscosity term \documentclass[12pt]{minimal}\begin{document}$\Delta _h u-M^2u$\end{document}Δhu−M2u, where M is a Fourier multiplier whose symbol \documentclass[12pt]{minimal}\begin{document}$m:\mathbb {R}\rightarrow \mathbb {R}^+$\end{document}m:R→R+ is non-negative. The case \documentclass[12pt]{minimal}\begin{document}$m(\xi _3)=|\xi _3|$\end{document}m(ξ3)=|ξ3| is essentially the Navier–Stokes system, while the case m = 0 is the anisotropic Navier–Stokes system. We obtain the global regularity in the case that \documentclass[12pt]{minimal}\begin{document}$m(\xi _3)\ge {|\xi _3|^{\frac{3}{2}}}/{g(|\xi _3|)}$\end{document}m(ξ3)≥|ξ3|32/g(|ξ3|) for all sufficiently large \documentclass[12pt]{minimal}\begin{document}$|\xi _3|$\end{document}|ξ3| where \documentclass[12pt]{minimal}\begin{document}$g:=\mathbb {R}^+\rightarrow \mathbb {R}^+$\end{document}g:=R+→R+ is a nondecreasing function such that \documentclass[12pt]{minimal}\begin{document}$\int ^\infty _1\frac{ds}{ g^2(s) s\ln s}=+\infty$\end{document}∫1∞dsg2(s)slns=+∞. Then, using the method of descent, we can obtain the classical global regularity result of the two-dimensional Navier–Stokes system.
Controlled microbubble generation on a compact disk
Authors: Chakraborty Debapriya , Chakraborty Suman
Published: December 2010

We develop a rotationally actuated fluidic device for controlled generation of microbubbles in a lab-on-a-compact-disk based environment. Use of such a strategy essentially implicates that one may employ simplistic, versatile, flexible, and economized microfabrication as well as fluidic actuation techniques, instead of more complex traditional methodologies, for microbubble generation and control. We further demonstrate that the spatio-temporal frequencies and size distributions of the generated bubbles may be judiciously controlled by simply tailoring the rotational speeds, corresponding to given channel dimensions and fluid-substrate combinations.
Observation of the spatial growth of self-excited dust-density waves
Authors: Flanagan T. M. , Goree J.
Published: December 2010

The growth of a naturally occurring dust-density wave (DDW) is experimentally observed using high-speed imaging. This low frequency wave (∼25 Hz) grows in amplitude as it propagates downward through a dusty plasma. The wave’s linear growth rate −ki is measured using a phase-sensitive analysis method. For the conditions studied here, the growth rate increases as gas pressure decreases. At a critical gas pressure, which is observed, a balance between an ion-flow instability and dissipation by neutral gas drag determines a threshold for wave propagation. A linear dispersion relation is derived, taking into account the effects of strong-coupling, to compare to the experiment.
Equity of access in the spatial distribution of GPs within an Australian metropolitan city
Authors: Roeger Leigh S. , Reed Richard L. , Smith Bradley P.
Published: December 2010

Equitable access to primary health care is a key objective for health policy makers. In Australia, poor access to primary care providers has been well documented for many rural areas, yet the distribution of general practitioners (GPs) in metropolitan regions remains relatively unknown. Traditional methods of determining geographic access to GPs are limited as they rely on simple population to provider ratios within artificial administrative borders and, among other things, fail to take into account patients that utilise close-by facilities outside of these borders. This study utilised specialised geographic information systems to examine the equity of access to GPs in an Australia capital city (Adelaide). Results showed that by Australian standards, residents of metropolitan Adelaide have low GP ratios. However, an inequitable spatial distribution of GPs within metropolitan Adelaide was found, with ~16% of residents considered to be living in areas of GP workforce shortage. Residents in the outer suburbs and those with lower social economic status appeared to be the most disadvantaged. It is recommended that future studies employ specialised GIS techniques as they provide a more accurate measurement of variations in spatial accessibility to primary care within metropolitan cities.