bluuebunny/crossref_metadata_2025 huggingface dataset:
Magnetoencephalographic Analysis of Gelastic Seizures in a Patient with Tuberous Sclerosis
Authors: Teraoka Satori , Imai Katsumi , Mano Toshi‐yuki , Okinaga Takeshi , Matsuoka Taro , Ono Jiro , Hira‐buki Norio , Abe Jiro , Okada Shintaro
Published: August 2009

Purpose: The ictal EEG and magnetoencephalogram (MEG) for gelastic seizures were recorded in a 4‐year‐old girl with tuberous sclerosis. The sites of origin for the seizure activities were investigated by using an equivalent current dipole (ECD) with the MEG.

Methods: EEG and MEG were recorded simultaneously under the administration of diazepam (DZP). The MEG recording was performed on a system consisting of an array of 64 sensors uniformly distributed over the patient's whole head (CTF, Canada), and the estimated ECDs were superimposed on the magnetic resonance imaging (MRI) images (Siemens, 1.5 Tesla).

Results: Two laughing attacks lasting 5 s each were documented. The ictal EEG showed gradually increasing 11–Hz rhythmic α activities with dominance over the frontocentral areas bilaterally, followed by irregular spike‐and‐wave discharges. The ictal MEG detected bilateral frontal rhythmic sharp waves before the appearance of the activities on the EEG. The estimated ECDs were localized in the deep white matter of the right frontal lobe on the MRI. However, those dipoles did not coincide with the locations of her cortical tubers.

Conclusions: Although gelastic seizures accompanied with hypothalamic hamartomas are well known, several reports have suggested a temporal or frontal lobe origin for gelastic seizures. In this patient, the ECD indicated that the seizures originated in the frontal lobe, although ictal scalp EEG recordings could not determine the precise focus. Thus, in cases in which the use of ictal scalp EEG fails to show the sites of origin for the seizures, it is recommended that the origins be estimated by using the non‐invasive method of ictal MEG analysis.
Efficacy of Thyrotropin‐Releasing Hormone in the Treatment of Intractable Epilepsy
Authors: Takeuchi Yoshihiro , Matsushita Hiroko , Uehara Hisakazu , Yamazoe Ichiro , Miyanomae Yuri , Takaya Kazushi , Sawada Tadashi
Published: August 2009

Purpose: Despite rapid advances in the treatment of epilepsy with the introduction of new drugs, the seizures in a number of children with epilepsy remain uncontrollable. Thus a more potent, yet safer therapy is needed. Adrenocorticotropic hormone (ACTH) has been used to treat children with intractable epilepsy, such as West syndrome and Lennox‐Gastaut syndrome. However, ACTH administration is occasionally associated with serious side effects, including immunosuppression, hypertension, and brain shrinkage. Consequently, in this study, the efficacy of an endogenous hormone, thyrotropin‐releasing hormone (TRH), was reevaluated for the treatment of intractable epilepsy.

Methods: From 1991 to 1996, we studied the efficacy of TRH‐tartrate (TRH‐T) in 34 children with intractable epilepsy (16 with West syndrome, 11 with Lennox‐Gastaut syndrome, three with localization‐related epilepsies, two with severe myoclonic epilepsy, one with early myoclonic encephalopathy, and one with Angelman syndrome). TRH‐T was administered intravenously or intramuscularly at a dose of 0.05 mg/kg/day once per day for 4 weeks. The subjects were classified into three groups based on the frequency of their seizures and the EEG effects: cessation of seizures and seizure discharges for >1 year (very effective group), a >50% reduction in the frequency of seizures or seizure discharges or both (effective group), and no changes in the frequency of seizures or seizure discharges (ineffective group).

Results: There were eight cases in the very effective group, 10 in the effective group, and 16 in the ineffective group. The patients in the very effective group stopped having seizures, including infantile spasms, tonic seizures, atypical absence, atonic seizures, myoclonic seizures, and partial seizures within 11 days to 3 months after the initiation of the TRH therapy. It is noteworthy that no seizures occurred for >3 years in four of the eight cases in the very effective group. The 16 patients with West syndrome comprised five cases in the very effective group, two in the effective group, and nine in the ineffective group. The 11 patients with Lennox‐Gastaut syndrome were subdivided into three cases in the very effective group, three in the effective group, and five in the ineffective group. All three patients with localization‐related epilepsies were in the effective group.

Conclusions: TRH should be considered as a possible treatment for Lennox‐Gastaut syndrome and West syndrome, especially for a patient who has an. infection or severe organic lesions in the brain, or who is immunosuppressed. It is noteworthy that TRH is also effective in the treatment of intractable localization‐related epilepsies. The relatively long duration of the action of TRH after the termination of administration may indicate that the mechanism for its anticonvulsant action differs from those of other anticonvulsant drugs.
A Typology of Inner–Ring Suburbs: Class, Race, and Ethnicity in U.S. Suburbia
Authors: Hanlon Bernadette
Published: August 2009

Inner–ring suburbs initially built in the postwar period and before have evolved into places with varied characteristics, assets, and problems. Analyzing a sample of 1,742 inner–ring suburbs nationwide, this article identifies five different types: “vulnerable;”“ethnic;”“lower income and mixed;”“old;” and “middle class.” This typology indicates that inner–ring suburbs, often perceived as homogenous entities, are in fact places largely differentiated by issues of class, race, and ethnicity. as this article demonstrates, the identification of these different types of inner–ring suburbs reveals much about suburban transformation, stability, and decline in the United States.
A Symposium on the Subprime Crisis
Authors: Immergluck Dan
Published: August 2009

The subprime crisis in mortgage lending and the resulting wave of foreclosures have been hitting cities and communities all over the United States. First, Dan Immergluck argues that there are three main elements in the financial crisis: (1) the vertical disintegration of the mortgage market and the related securitization; (2) financial deregulation; and (3) the burgeoning supply of high–risk capital. Second, Manuel Aalbers counters the view that the Community Reinvestment Act (CRA) and the associated community reinvestment movement can be blamed for the subprime mortgage crisis. He lists five reasons why the CRA is not guilty. Third and finally, Peter Marcuse sees the subprime crisis as a result of the underlying economic system. He argues that the private sector should not be viewed as the appropriate means of providing housing. He discusses a number of proposals that impact on the crisis and its roots.
Effect of Alkali Elements Content on the Structure and Electrical Properties of (K0.48Na0.48Li0.04)(Nb0.90Ta0.04Sb0.06)O3 Lead‐Free Piezoelectric Ceramics
Authors: Lin Dunmin , Kwok Kin Wing , Chan Helen Lai‐wa
Published: August 2009

In this communication, we report on the effects of alkaline elements (K, Na, and Li) content on the electrical properties of (K0.48Na0.48Li0.04)(Nb0.90Sb0.06Ta0.04)O3 ceramics. Because of the high volatility, the alkaline elements evaporate during the high‐temperature sintering process, generating vacancy defects in the ceramics. As a result, the ferroelectric and piezoelectric properties of the ceramics become weakened. Our results reveal that the volatilization loss can be effectively compensated by a 1 mol% excess of alkaline elements. The remanent polarization Pr, piezoelectric coefficient d33, and electromechanical coupling coefficient kp of the compensated ceramics are improved by 15%, 16%, and 20%, respectively, having a value of 30 μC/cm2, 310 pC/N, and 0.6.
Maxillary sinus floor elevation using a tissue‐engineered bone complex with β‐TCP and BMP‐2 gene‐modified bMSCs in rabbits
Authors: Jiang X.‐Q. , Sun X.‐J. , Lai H.‐C. , Zhao J. , Wang S.‐Y. , Zhang Z.‐Y.
Published: August 2009

Objectives: To study the effects of maxillary sinus floor elevation by a tissue‐engineered bone complex with β tricalcium phosphate (β‐TCP) and bone morphogenetic protein‐2 (BMP‐2) gene‐modified bone marrow stromal cells (bMSCs) in rabbits.

Material and methods: bMSCs derived from New Zealand rabbit bone marrow were cultured and transduced with the adenovirus with BMP‐2 (AdBMP‐2), adenovirus with enhanced green fluorescent protein gene (AdEGFP) in vitro. Gene transfer efficiency was detected by EGFP expression. These gene‐modified autologous bMSCs were then combined with a β‐TCP granule scaffold at a concentration of 2 × 107 cells/ml and used to elevate the maxillary sinus floor in rabbits. Twenty rabbits were randomly allocated into groups and sacrificed at weeks 2 and 8. For each time point, 20 maxillary sinus floor elevation surgeries were made bilaterally in 10 rabbits for the following groups (n=5 per group): group A (β‐TCP alone), group B (untransduced bMSCs/β‐TCP), group C (AdEGFP–bMSCs/β‐TCP), and group D (AdBMP‐2–bMSCs/β‐TCP). All samples were evaluated by histology and histomorphometric analysis. The fate of implanted bMSCs was traced initially by a confocol fluorescent microscope in the AdEGFP group.

Results: Gene transfer efficiency reached up to 60–80% with 50 PFU/cell transduction as demonstrated by fluorescent microscopic analysis in the AdEGFP group. The augmented maxillary sinus height was maintained for the four groups till 8 weeks post‐surgery, while new bone area increased over the time. At week 2, bone areas in groups B–D were significantly larger than those in group A, while at week 8, in group D, the BMP‐2 gene‐enhanced tissue‐engineered bone had the largest bone area among the groups (P<0.05, ANOVA). In that group, a mature bone structure was detected in the center of the elevated space. Under a confocal microscope, green fluorescence in newly formed bone was observed for the EGFP group, which suggested that those implanted bMSCs might have contributed to the new bone formation.

Conclusion: bMSCs modified with the AdBMP‐2 gene can promote new bone formation and maturation in the rabbit maxillary sinus. BMP‐2 regional gene therapy and a tissue engineering technique could be effectively used in maxillary sinus elevation and bone regeneration.
The effect of thread pattern upon implant osseointegration
Authors: Abuhussein Heba , Pagni Giorgio , Rebaudi Alberto , Wang Hom‐Lay
Published: August 2009

Objectives: Implant design features such as macro‐ and micro‐design may influence overall implant success. Limited information is currently available. Therefore, it is the purpose of this paper to examine these factors such as thread pitch, thread geometry, helix angle, thread depth and width as well as implant crestal module may affect implant stability.

Search Strategy: A literature search was conducted using MEDLINE to identify studies, from simulated laboratory models, animal, to human, related to this topic using the keywords of implant thread, implant macrodesign, thread pitch, thread geometry, helix angle, thread depth, thread width and implant crestal module.

Results: The results showed how thread geometry affects the distribution of stress forces around the implant. A decreased thread pitch may positively influence implant stability. Excess helix angles in spite of a faster insertion may jeopardize the ability of implants to sustain axial load. Deeper threads seem to have an important effect on the stabilization in poorer bone quality situations. The addition of threads or microthreads up to the crestal module of an implant might provide a potential positive contribution on bone‐to to‐implant contact as well as on the preservation of marginal bone; nonetheless this remains to be determined.

Conclusions: Appraising the current literature on this subject and combining existing data to verify the presence of any association between the selected characteristics may be critical in the achievement of overall implant success.

To cite this article:
 Abuhussein H, Pagni G, Rebaudi A, Wang H‐L. The effect of thread pattern upon implant osseointegration. Clin. Oral Impl. Res. 21, 2010; 129–136. doi: 10.1111/j.1600‐0501.2009.01800.x
Panniculitis: clinical overlap and the significance of biopsy findings
Authors: Chopra Rajan , Chhabra Seema , Thami Gurvinder Pal , Punia Raj Pal Singh
Published: August 2009

Background: Panniculitides are well‐recognized clinicopathologic entities but the non‐specificity of their clinical and pathological features often troubles the diagnostician.

Methods: This study retrospectively evaluates the clinical overlaps and the significance of histological findings among various panniculitides.

Results: The clinical evaluation in 55 panniculitides cases suggested the diagnosis of typical erythema nodosum (EN) in 26 cases, atypical EN in 17 cases, atypical nodular vasculitis (NV) in two cases, soft tissue infection in five cases and five cases remained unclassified. Skin biopsy evaluation provided definite panniculitis diagnosis in 53 cases including EN (28 cases), leukocytoclastic vasculitis (seven cases), NV (four cases), superficial thrombophlebitis (ST) (two cases), eosinophillic panniculitis (EP) (three cases), infection‐related panniculitis (five cases), and one case each of erythema nodosum leprosum (ENL), lupus panniculitis (LP), pancreatic fat necrosis and acne conglobata with two cases remaining unclassified. Histologically, ‘predominantly septal’ and ‘mixed panniculitis' were the chief inflammatory patterns in EN cases, while mixed panniculitis was seen in most LCV cases and predominantly lobular and mixed panniculitis in NV cases.

Conclusions: Biopsy evaluation of a panniculitis lesion is usually significant, and the application of a combination of histologic features rather than of a single biopsy finding or an inflammatory pattern is helpful in the diagnosis of panniculitis.
Haematologic data, iron parameters and molecular findings in two new cases of iron‐refractory iron deficiency anaemia
Authors: Tchou Isabelle , Diepold Myriam , Pilotto Pierre‐Antonio , Swinkels Dorine , Neerman‐Arbez Marguerite , Beris Photis
Published: August 2009

Matriptase‐2 (Tmprss6), a type II transmembrane serine protease, has an essential role in iron homoeostasis as a hepcidin regulator. Recently, patients with TMPRSS6 mutations and suffering from iron‐refractory iron deficiency anaemia (IRIDA) have been reported. We describe two new cases of IRIDA, one patient of Swiss origin and the second of Italian origin. The first case results from a large deletion of 1054 nucleotides corresponding to an in frame deletion of 30 amino acid residues in the low‐density lipoprotein receptor‐1/‐2 (LDLR‐1/‐2) domains and from a missense mutation in CUB1 (S304L). In the second case, a homozygous G→C mutation in the last nucleotide of exon 15 and which modified the consensus sequence of the 5′ splice donor site of intron 15 (AGgt→ACgt) was identified. Both patients had a high hepcidin level and low serum iron and transferrin saturation compared to age‐matched controls. Continuous perfusion of i.v. iron 4 h/d × 5 d in the first case resulted in a significant rise in haemoglobin. These new cases of IRIDA illustrate the importance of LDLR‐1/‐2 and CUB1 domains in matriptase‐2 function as well as the role of matriptase‐2 in hepcidin regulation. Furthermore a deletional form of TMPRSS6 (in LDLR‐1/‐2 domains) resulting in IRIDA is described for the first time. These cases reinforce the belief that patients suffering from IRIDA have no specific geographical or ethnic distribution and are sporadic secondary to different mutations of the matriptase‐2 gene.
ORIGINAL ARTICLE: Serum IL‐6 Level May Have Role in the Pathophysiology of Unexplained Infertility
Authors: Demir Bulent , Guven Suleyman , Guvendag Guven Emine Seda , Atamer Yildiz , Gul Talip
Published: August 2009

Problem  The aim of this study was to compare the serum levels of interleukin (IL)‐6 of women with unexplained infertility with fertile subjects.

Method of study  Serum IL‐6, and tumor necrosis factor‐α (TNF‐α) levels of 45 infertile and 44 fertile women on day 3 of menstrual cycle were assessed and compared for this prospective controlled study.

Results  The mean serum IL‐6 level was significantly higher in women with unexplained infertility, compared with fertile women (5.71 ± 1.81 and 4.31 ± 1.79, P < 0.001, Student’s t‐test). There was no significant difference in TNF‐α level among the groups.

Conclusion  Significant difference in serum IL‐6 levels between unexplained infertile and fertile women suggests that this cytokine may be involved in pathophysiology of unexplained infertility.
Factors associated with self‐assessed oral health in the Japanese independent elderly
Authors: Konishi Chisato , Hakuta Chiyoko , Ueno Masayuki , Shinada Kayoko , Wright Fredrick A. C. , Kawaguchi Yoko
Published: August 2009

doi:10.1111/j.1741‐2358.2009.00310.x
 
Factors associated with self‐assessed oral health in the Japanese independent elderly

Objectives:  The purpose of this research was to analyse the relationship between oral health status, oral motor function, daily life situations and self‐assessed oral health.

Materials and methods:  A cross‐sectional survey was conducted on 190 independent elderly volunteers aged 62–99 years from senior citizen centres in Tokyo, Japan. A questionnaire survey and oral examination were conducted on each participant. For the descriptive analyses, Independent t‐test and the chi‐squared test were used. Following that, using four latent variables, (oral health, oral function, daily life situations and chronic health condition), a structural equation modelling analysis (SEMA) was undertaken.

Results:  In the descriptive analyses, there were no significant differences between self‐assessed oral health and oral health status. However, there were significant differences between self‐assessed oral health and oral function and daily life situations. Findings from SEMA revealed that daily life situations and oral function have independent effects on self‐assessed oral health and that the relationship between self‐assessed oral health and oral health status was weak.

Conclusions:  Many factors affect self‐assessed oral health status. Dental clinicians and researchers should attempt to understand these factors and incorporate them into effective personal and population‐based oral health education and oral health promotion programmes.
Effect of the physical properties of acrylic resin of overnight immersion in sodium hypochlorite solution
Authors: Davi Letícia Resende , Peracini Amanda , de Queiroz Ribeiro Nathália , Soares Rafael Bellini , da Silva Cláudia Helena Lovato , de Freitas Oliveira Paranhos Helena , de Souza Raphael Freitas
Published: August 2009

doi:10.1111/j.1741‐2358.2009.00336.x
 
Effect of the physical properties of acrylic resin of overnight immersion in sodium hypochlorite solution

Objectives:  This study evaluated colour stability, surface roughness and flexural strength of microwave‐polymerised acrylic resin after overnight immersion in sodium hypochlorite, simulating 180 days use.

Materials and methods:  Forty disc‐shaped (15 mm × 4 mm) and 40 rectangular specimens (65 mm × 10 mm × 3 mm) were prepared from microwave‐polymerised acrylic resin. The specimens were immersed in 0.5, 1% sodium hypochlorite, Clorox/Calgon and distilled water. Colour measurements (ΔE) were determined by a portable colorimeter. A surface analyser was used to measure roughness (μm). The flexural strength (MPa) was measured using a three‐point bending test in a universal testing machine. Data were evaluated by one‐way anova, followed by Student–Newman–Keuls test (α = 0.05).

Results:  Statistical analysis found significantly higher colour changes (SNK, p < 0.001) for the 1% sodium hypochlorite, but mean ΔE value quantified by National Bureau of Standards was classified as slight. When comparing the surface roughness, no statistical significance was found among the solutions (anova, p = 0.637). The 1% sodium hypochlorite presented significantly lower flexural strength compared with the control group (SNK, p = 0.034).

Conclusion:  It was concluded that immersion in 1% sodium hypochlorite solutions for 8 h does influence the colour stability and flexural strength of microwave‐polymerised acrylic resin, during the simulated period of 180 days.
Palms Use a Bluffing Strategy to Avoid Seed Predation by Rats in Brazil
Authors: de Sampaio e Paiva Camilo‐Alves Constança , de Miranda Mourão Guilherme
Published: August 2009

The goal of this study was to ascertain why the production of variable seediness is advantageous for Attalea phalerata palms. Our hypothesis was that variation reduces seed predation by the spiny rats Thrichomys pachyurus and Clyomys laticeps. Although there is a positive correlation between endocarp size and number of seeds, endocarps sometimes contain more or fewer seeds than expected; palms bluff about the number of seed per endocarp. Therefore, rats do not know how many seeds an endocarp contains. To model rats' predating behavior, we applied Charnov's Marginal Value Theorem. The model shows that rats attack endocarps only when the energy gain is higher than the energy available in the habitat. Hence, it is not advantageous to eat all the seeds inside an endocarp. This explains why 45 percent of forest endocarps and 35 percent of savanna endocarps were still viable after predation. We then applied the model to two simulated endocarp populations with less variability in the number of seeds per endocarp size and determined that viable diaspores after predation were reduced to 15 percent. With less variability, palms cannot bluff about the number of seeds inside endocarps and predators can predict accurately how many seeds they should try to eat. Uncertainty about the number of seeds diminished predation but gave selective advantage to multiseeded fruits. Therefore, the bluffing strategy would be evolutionarily stable only if it were counterbalanced by other forces. Otherwise, predators would win the bluffing game.

Abstract in Portuguese is available at http://www.blackwell‐synergy.com/loi/btp.
Evolution and chemical yields of AGB stars: effects of low-temperature opacities
Authors: Ventura P. , Marigo P.
Published: August 2009

The studies focused on the thermally pulsing asymptotic giant branch phase experienced by low- and intermediate-mass stars are extremely important in many astrophysical contexts. In particular, a detailed computation of their chemical yields is essential for several issues, ranging from the chemical evolution of galaxies to the mechanisms behind the formation of globular clusters. Among all the uncertainties affecting the theoretical modelling of this phase, and described in the literature, it remains to be fully clarified which results are severely affected by the use of inadequate low-temperature opacities, which are in most cases calculated on the basis of the original chemical composition of the stars, and do not consider the changes in the surface chemistry due to the occurrence of the third dredge-up and hot-bottom burning. Our investigation is aimed at investigating this point. By means of full evolutionary models including a new set of molecular opacities computed specifically with the æsopus tool, we highlight which stellar models, among those present in the literature, need a substantial revision, mainly in relation to the predicted chemical yields. The interplay among convection, hot-bottom burning and the low-temperature opacity treatment is also discussed.
Quiet but still bright: XMM—Newton observations of the soft gamma-ray repeater SGR0526—66
Authors: Tiengo A. , Esposito P. , Mereghetti S. , Israel G. L. , Stella L. , Turolla R. , Zane S. , Rea N. , Götz D. , Feroci M.
Published: August 2009

SGR 0526–66 was the first soft gamma-ray repeater from which a giant flare was detected in 1979 March, suggesting the existence of magnetars, i.e. neutron stars powered by the decay of their extremely strong magnetic field. Since then, very little information has been obtained on this object, mainly because it has been burst inactive since 1983 and the study of its persistent X-ray emission has been hampered by its large distance and its location in a X-ray bright supernova remnant in the Large Magellanic Cloud. Here, we report on a comprehensive analysis of all the available XMM–Newton observations of SGR 0526–66. In particular, thanks to a deep observation taken in 2007, we measured its pulsation period (P= 8.0544 ± 0.0002 s) 6 years after its latest detection by Chandra. This allowed us to detect for the first time a significant reduction of its spin-down rate. From a comparison with two shorter XMM–Newton observations performed in 2000 and 2001, we found no significant changes in the spectrum, which is well modelled by an absorbed power law with NH= 4.6+0.7−0.5× 1021 cm−2 and Γ= 3.27+0.07−0.04. The high luminosity (∼4 × 1035 erg s−1, in the 1–10 keV energy band) still observed ∼25 years after the latest detection of bursting activity places SGR 0526–66 in the group of bright and persistent magnetar candidates.
Competing local and non-local α-effects for a simplified flux transport dynamo model
Authors: Mann P. D. , Proctor M. R. E.
Published: August 2009

The solar magnetic field is maintained by a hydromagnetic dynamo, and it is generally accepted that strong toroidal magnetic field is produced at the tachocline below the solar convection zone. The location of production of the poloidal field via the α-effect is still in question. One such location is the solar surface, where decay of bipolar magnetic regions produces poloidal magnetic field; this is known as the Babcock–Leighton mechanism. Another possible location is the base of the solar convection zone. Recent work has looked at the competition in the solar dynamo between surface and deep-seated α-effects. The α-effects studied were local effects. However, flux-transport dynamo calculations use non-local poloidal source terms, that is they act at the surface but are proportional to the toroidal field at the base of the convection zone. We will discuss the effects of non-local competing α-effects on the dynamo equations to explore the validity of this type of model. We will also include the effects of meridional circulation.
A fuzzy‐dependent chance multi‐objective programming for water resources planning of a coastal city under fuzzy environment
Authors: Peng Hui , Zhou Huicheng
Published: August 2009

A fuzzy multi‐objective water resources management model is developed to determine the satisfactory water allocation plan in a coastal city of Northeast China. The imprecise predicted values of parameters are represented by fuzzy numbers, and seven fuzzy objectives of maximizing the possibilities of satisfying the water requirements for six users and total cost less than the expected value are considered. After weighted summation method (WSM) is used to transform the multi‐objective model into a single‐objective model, the satisfactory water allocation plan is efficiently derived according to decision makers' preferences by using a hybrid solution procedure of combining genetic algorithm with fuzzy simulation technique. Results of sensitivity test imply that the interval [0.2, 0.6] of cutting level, surface water and groundwater supplies have the most sensitive influence on results of the model. Moreover, results of discussion demonstrate that the assumption of linearity can be accepted, and membership function of fuzzy number has little influence on results of the model.
The Rock Varnish Revolution: New Insights from Microlaminations and the Contributions of Tanzhuo Liu
Authors: Dorn Ronald I.
Published: August 2009

Rock varnish is a coating composed of clay minerals cemented to rock surfaces by oxides of manganese and iron. Although this dark brown‐to‐black accretion is most noticeable in arid regions, it occurs in all terrestrial weathering environments. Scholarly varnish research started with Alexander von Humboldt, when he asked how this external accretion forms and why manganese concentrations in varnish are 101–102 greater than in potential source materials. In the ensuing two centuries, investigations into rock varnish have been characterized by researchers studying only a handful of samples who have often used limited data to draw general conclusions. In contrast, nearly two decades of work by Tanzhuo Liu of Columbia University has yielded more than 10,000 varnish microstratigraphies obtained from rock depressions, analyses of which have provided new insights into the origin of rock varnish and the nature of climatic change in deserts, in addition to opening new research avenues in geomorphology and geoarchaeology.
Governments‐in‐Exile: Statehood, Statelessness and the Reconfiguration of Territory and Sovereignty
Authors: McConnell Fiona
Published: August 2009

Governments‐in‐exile are conventionally viewed as discrepant forms of political practice and geopolitical exceptions to the rules of sovereign statehood. However, despite significant limitations, polities such as the Tibetan Government‐in‐Exile enact state‐like functions and are actively forging new political spaces and modalities of sovereignty. Contextualising governments‐in‐exile with regards to a range of twentieth‐century geopolitical anomalies, this study argues that such polities raise key questions for political geographers regarding the relationship between sovereignty and territory, the nature of statehood and the role of ‘the exception’ in geopolitical discourses. In light of contemporary critical reappraisals of sovereignty, territory and statehood, this study calls for political geography – and critical geopolitics in particular – to expand its gaze and engage with issues raised by governments‐in‐exile. In turn, an empirical and theoretical focus on such non‐state entities highlights the utility of ethnographic methodologies within critical geopolitics, enables a critical fusion of literatures of the state and of statelessness, problematises taken‐for‐granted political geography categories and facilitates critical inquiry into alternative political arrangements.
Chemically Bonded Hybrid Systems from Functionalized Hydroxypyridine Molecular Bridge: Characterization and Photophysical Properties
Authors: Yan Bing , Qian Kai
Published: August 2009

A series of novel photoactive hybrid materials with organic parts covalently linked to inorganic parts via the acylamino group have been assembled by sol–gel process. The organic parts as molecular bridge derive from α‐hydroxypyridine (HP) functionalized by 3‐(triethoxysilyl)‐propyl isocyanate (TESPIC). Finally homogeneous, molecular‐based hybrid materials with different microstructure (uniform spherical or clubbed) are obtained, in which no phase separation is observed. This may be ascribed as the different coordination behavior of metal ions (Eu3+ (Tb3+) or Zn2+). Red emission of Eu–HP–Si, green emission of Tb–HP–Si and violet‐blue luminescence of Zn–HP–Si hybrids can be achieved within these molecular‐based hybrid materials. Besides, both Eu(Tb) and Zn are introduced into the same hybrid systems (Eu(Zn)–HP–Si or Tb(Zn)–HP–Si) through the covalent Si–O bond, whose sphere particle size can be modified. Especially the photoluminescence behavior can be enhanced, suggesting that intramolecular energy transfer takes place between inert Zn2+ and Eu3+ (Tb3+) in the covalently bonded hybrid systems.
Masticatory dysfunction in patients with myotonic dystrophy (type 1): a 5‐year follow‐up
Authors: Umemoto George , Nakamura Hirokazu , Oya Yasushi , Kikuta Toshihiro
Published: August 2009

Eight patients with myotonic dystrophy type 1, DM1 (age range 45–63 years) were followed for a period of 5 years. Two sets of data analyzing masticatory function and activities of daily living (ADL) were obtained at baseline and at 5 years. The results from both time points were compared. The number of food items considered easy to chew, maximum bite force, occlusal contact area, number of teeth, and ADLs were significantly reduced (p < 0.05) at the second assessment when compared to the first. During the intervening 5 years, six of the eight patients adopted a soft diet. These results suggest deterioration in ADLs and masticatory function of patients with DM1. Continuous evaluation of the feeding ability and the type of diet are necessary for patients with DM1.
Oral home telecare for adults with tetraplegia: a feasibility study
Authors: Yuen Hon K. , Pope Charlene
Published: August 2009

This pilot study investigated the feasibility of delivering an individualized program of oral home telecare training using PC‐based, real‐time interactive videoconferencing via the Internet to meet the unique challenges of dental care for people with tetraplegia. A home‐based videoconferencing method was tested with two adults with tetraplegia and an occupational therapist (rehabilitation specialist). As part of the proposed rehabilitation training to improve independence in performing oral hygiene, adaptive devices (a rechargeable oscillating‐rotating power toothbrush and a cordless oral irrigator) were introduced to facilitate oral care performance with interactive, Web‐based instruction. Training was conducted once a week for 4 weeks. The oral home telecare experience was evaluated using a questionnaire and in‐depth interviews after the training. Both subjects were satisfied with the oral home telecare services and were enthusiastic about using the services without major difficulty after having previously experienced barriers to dental care. In addition to their positive perceptions about videoconferencing, the subjects suggested adaptations and identified unexpected potential uses for interactive videoconferencing. The use of interactive videoconferencing as a mode of oral hygiene training may lead to a change in oral hygiene service delivery methods, improving accessibility to geographically dispersed populations with tetraplegia. Oral home telecare offers strategies to decrease physical barriers and communication difficulties that correspond to recommendations to improve the quality of dental health services for people with tetraplegia.
Hear the Wnt Ror: how melanoma cells adjust to changes in Wnt
Authors: O’Connell Michael P. , Weeraratna Ashani T.
Published: August 2009

The interplay between canonical and non‐canonical Wnt pathways in development and tumorigenesis is tightly regulated. In this review we will describe the yin and the yang of canonical and non‐canonical Wnt signaling pathways during melanocyte development, and melanoma genesis. Canonical Wnt signaling, represented by Wnts such as Wnt1 and Wnt3A, signals via β‐catenin to promote melanocyte differentiation and tumor development. Non‐canonical Wnt signaling, specifically Wnt5A, regulates canonical pathways, and signals to induce melanoma metastasis. This review will focus on the role of Wnt5A during melanoma progression, and its relationship to canonical Wnt signaling.
Defining the excitatory neurons that drive the locomotor rhythm in a simple vertebrate: insights into the origin of reticulospinal control
Authors: Soffe Stephen R. , Roberts Alan , Li Wen‐Chang
Published: August 2009

Important questions remain about the origin of the excitation that drives locomotion in vertebrates and the roles played by reticulospinal neurons. In young Xenopus tadpoles, paired whole‐cell recordings reveal reticulospinal neurons that directly excite swimming circuit neurons in the brainstem and spinal cord. They form part of a column of neurons (dINs) with ipsilateral descending projections which fire reliably and rhythmically in time with swimming. We ask if, at this early stage of development, these reticulospinal neurons are themselves the primary source of rhythmic drive to spinal cord neurons on each cycle of swimming. Loose‐patch recordings in the hindbrain and spinal cord from neurons active during fictive swimming distinguished dINs from other neurons by spike shape. These recordings showed that reticulospinal dINs in the caudal hindbrain (rhombomeres 7–8) fire significantly earlier on each swimming cycle than other, ipsilateral, swimming circuit neurons. Whole‐cell recordings showed that fast EPSCs typically precede, and probably drive, spikes in most swimming circuit neurons. However, the earliest‐firing reticulospinal dINs spike too soon to be driven by underlying fast EPSCs. We propose that rebound following reciprocal inhibition can contribute to early reticulospinal dIN firing during swimming and show rebound firing in dINs following evoked, reciprocal inhibitory PSPs. Our results define reticulospinal neurons that are the source of the primary, descending, rhythmic excitation that drives spinal cord neurons to fire during swimming. These neurons are an integral part of the rhythm generating circuitry. We discuss the origin of these reticulospinal neurons as specialised members of a longitudinally distributed population of excitatory interneurons extending from the brainstem into the spinal cord.
Intra‐sarcoplasmic reticulum Ca2+ oscillations are driven by dynamic regulation of ryanodine receptor function by luminal Ca2+ in cardiomyocytes
Authors: Stevens Sarah C.W. , Terentyev Dmitry , Kalyanasundaram Anuradha , Periasamy Muthu , Györke Sandor
Published: August 2009

During the cardiac cycle, the release of Ca2+ from the sarcoplasmic reticulum (SR) through the ryanodine receptor (RyR2) channel complex is controlled by the levels of cytosolic and luminal Ca2+ and alterations in these regulatory processes have been implicated in cardiac disease including arrhythmia. To better understand the mechanisms of regulation of SR Ca2+ release by Ca2+ on both sides of the SR membrane, we investigated SR Ca2+ release in a wide range of cytosolic Ca2+ concentrations ([Ca2+]cyt; 1–100 μm) in permeabilized canine ventricular myocytes by monitoring [Ca2+] inside the SR ([Ca2+]SR). Exposing myocytes to activating [Ca2+]cyt resulted in spontaneous oscillations of [Ca2+]SR due to periodic opening and closing of the RyR2s. Elevating [Ca2+]cyt (up to 10 μm) increased the frequency of [Ca2+]SR oscillations; however at higher [Ca2+]cyt (>50 μm) the oscillations diminished due to RyR2s staying perpetually open, resulting in depleted SR. Ablation of cardiac calsequestrin (CASQ2) altered the [Ca2+]cyt dependence of Ca2+ release oscillations such that oscillations were highly frequent at low [Ca2+]cyt (100 nm) but became diminished at moderate [Ca2+]cyt (10 μm), as determined in myocytes from calsequestrin‐null versus wild‐type mice. Our results suggest that under conditions of continuous activation by cytosolic Ca2+, RyR2s can periodically cycle between open and deactivated states due to effects of luminal Ca2+. Deactivation at reduced [Ca2+]SR appears to involve reduction of sensitivity to cytosolic Ca2+ and might be mediated by CASQ2. Inactivation by cytosolic Ca2+ plays no detectable role in controlling SR Ca2+ release.
A Ca2+‐activated Cl− conductance in interstitial cells of Cajal linked to slow wave currents and pacemaker activity
Authors: Zhu Mei Hong , Kim Tae Wan , Ro Seungil , Yan Wei , Ward Sean M. , Koh Sang Don , Sanders Kenton M.
Published: August 2009

Interstitial cells of Cajal (ICC) are unique cells that generate electrical pacemaker activity in gastrointestinal (GI) muscles. Many previous studies have attempted to characterize the conductances responsible for pacemaker current and slow waves in the GI tract, but the precise mechanism of electrical rhythmicity is still debated. We used a new transgenic mouse with a bright green fluorescent protein (copGFP) constitutively expressed in ICC to facilitate study of these cells in mixed cell dispersions. We found that ICC express a specialized ‘slow wave’ current. Reversal of tail current analysis showed this current was due to a Cl− selective conductance. ICC express ANO1, a Ca2+‐activated Cl− channel. Slow wave currents are not voltage dependent, but a secondary voltage‐dependent process underlies activation of these currents. Removal of extracellular Ca2+, replacement of Ca2+ with Ba2+, or extracellular Ni2+ (30 μm) blocked the slow wave current. Single Ca2+‐activated Cl− channels with a unitary conductance of 7.8 pS were resolved in excised patches of ICC. These are similar in conductance to ANO1 channels (8 pS) expressed in HEK293 cells. Slow wave current was blocked in a concentration‐dependent manner by niflumic acid (IC50= 4.8 μm). Slow wave currents are associated with transient depolarizations of ICC in current clamp, and these events were blocked by niflumic acid. These findings demonstrate a role for a Ca2+‐activated Cl− conductance in slow wave current in ICC and are consistent with the idea that ANO1 participates in pacemaker activity.
Design Study of a Superheater Header Subjected to Cyclic and High Temperature Loading
Authors: Shi Jinhua
Published: August 2009

A typical superheater header in a power station is normally subject to high pressure and high temperature loading. Due to increasing fuel prices, many stations especially gas fired power stations are operated cyclically to increase flexibility and to reduce the running costs. Accordingly, new design of heat recovery steam generators (HRSGs) has been required to undertake cyclic operations. For a base load superheater header, the design life is dominated by material creep properties (time to rupture). However, for a header subjected to two shift cyclic operating conditions, fatigue damage could be increased significantly. Therefore, creep-fatigue interaction should be considered. In this paper, a creep-fatigue design life study of a typical HRSG superheater header has been conducted under various cyclic conditions. Creep stresses for the header are calculated using a reverse design code method, and the creep damage is then obtained based on the time to rupture data. Meanwhile, fatigue calculations are carried out using the methodology given in a new European boiler design code BS EN 12952. The results of creep and fatigue damage obtained are presented in a creep-fatigue interaction diagram shown in ASME III Section NH (former N47 Case) for comparisons. After a brief discussion of the results, a conclusion is drawn.
Modelling the Strain-Life Relationship of Commercial Alloys
Authors: Guo Zhanli , Saunders Nigel , Miodownik Peter , Schille Jean-Philippe
Published: August 2009

Premature fatigue fractures in structural components are a major problem in the manufacturing industry. The challenge for modellers has been to deliver reliable fatigue-analysis tools, because over-designing components is becoming an increasingly unattractive solution to the problem. Currently software packages exist for fatigue simulation of components or systems. However, a common feature of such software is that they all require the fatigue properties of the materials used. When such information is not available, the fatigue simulation cannot proceed until relevant experimental measurements are carried out, which can be both time-consuming and very costly. It is the aim of the current work to help solve this dilemma by developing models that can calculate the strain-life relationship not only at room temperature but also high temperatures. This work extends previous successful models for predicting the monotonic material properties of commercial alloys as a function of alloy chemistry, heat treatment, temperature and strain rate. In the present paper, attempts are made to model the high temperature fatigue properties of some engineering alloys. The effect of strain rate and cyclic loading frequency on fatigue properties are also discussed.
Determination and Modeling of the Creep Propagation on High Chromium Steel
Authors: Ancelet Olivier , Chapuliot Ste´phane
Published: August 2009

Modified 9Cr-1Mo steel (T91) is a candidate material for pressure vessels and for some internal structures of GCR (Gas Cooled Reactors). In order to validate this choice, it is necessary, to check if it is covered by the existing design codes, concerning its procurement, fabrication, welding, examination methods and mechanical design rules. A large R&D program on mod 9Cr-1Mo steel has been undertaken at CEA in order to characterize the behavior of this material and of its welded junctions. In this program, the role of the Laboratory for structural Integrity and Standards (LISN) is to develop high temperature defect assessment procedures under fatigue, creep and creep-fatigue loadings, to validate the existing methods (developed on austenitic stainless steels as 316L(N) for the fast reactors) and to get new experimental data on Mod 9Cr-1Mo steel. This paper presents the experimental program undertaken to develop defect assessment under creep loading and describes the main results obtained. Then a creep propagation law is proposed for the Mod 9Cr-1Mo steel at 550°C. To validate the experimental interpretation, a numerical analysis with a 3D finite element model is proposed and allows to model the propagation of the crack. Finally, a comparison of the experimental and the numerical data and in particular of the C* value is investigated.
Assessing Creep Damage in Cast Materials for High Temperature Reformer Tube Applications
Authors: Shannon Brian
Published: August 2009

Centrifugally cast materials, namely HK-40, HP Modified and Micro-Alloy materials are used in Steam Reformer tube applications. These materials, operating in the creep range, are subject to time/temperature related degradation which can manifest in several ways. The quantification of damage is of vital importance if tube life is to be predicted accurately. A comprehensive nondestructive inspection approach has been developed to assess the exact degree of damage. The approach utilizes several NDE techniques including ultrasonic, eddy current and dimensional measurements. The combination of the techniques provides valuable data for establishing condition assessment and remaining tube life prediction. Experiences and findings are discussed in the paper. Discussion of destructive methodologies for tube life assessment are beyond the scope of this paper.
State-of-the-Art Improvements in Coke Drum Design and Life Extension Practices
Authors: Boswell Richard S. , Wright Bobby
Published: August 2009

Coke drums are vessels critical to the operation and profitability of today’s oil refinery and tar sands facilities. These vessels operate in batch cycles at relatively high temperatures, ∼800F+, and about once a day they are filled with vapor and hot oil and finally quenched with water. They have historically been designed according as ASME Section VIII Division 1 pressure vessels with little or no account for the cyclic operation or fatigue service in which they operate. In the past ten years, the frequency and severity of these cycles dramatically increased while cycle times steadily decreased from 24 to 12 hour cycles and, more recently, to as low as 10 hour cycles. As a result, coke drums with few or no previous problems began to crack through wall in the shell and/or skirt region. In addition, many new coke drums are cracking through wall in as few as four to five years because they were not designed for the more severe fatigue service in which they currently operate. These observations have been learned by extensive monitoring and evaluation: • drums experienced lower switch temperatures (inadequate pre-warm for the skirt), • drums were heated and cooled much faster than anticipated, • contraction of the drum walls compacted the coke, • feed stocks were now different and produced harder coke, • reducing cycle times by as little as two hours caused average fatigue damage per cycle to increase by more than 30%. All of these occurrences can increase cyclic stress on drums and significantly accelerate cracking.