bluuebunny/crossref_metadata_2025 huggingface dataset:
Enhancement of Palladium‐Porphyrin Room Temperature Phosphorescence by Alkaline Earth Metal in Deoxycholate Aggregates Solution
Authors: Wang Ying‐Te , Wang Xiang‐Wei , Zhang Yong
Published: March 2011

Room temperature phosphorescence (RTP) of three palladium (Pd)‐phorphyrins in air‐saturated solution of sodium deoxycholate (NaDC) aggregates was measured. RTP of Pd‐meso‐tetrakis (4‐carboxyphenyl) porphyrin (Pd‐TCPP) was obviously enhanced in NaDC‐aggregates mediated by alkaline earth metal (AEM). Under the same experimental conditions, Ca2+, Ba2+ and Mg2+ induced 200, 90 and 24 times greater enhancement in RTP of Pd‐TCPP, respectively. It is ascribed to form the complex of NaDC‐aggregate/AEM/Pd‐TCPP in the system. The positively charged AEM has a strong capability of co‐ordination with negatively charged carboxyl groups of NaDC and Pd‐TCPP. The phosphor Pd‐TCPP is confined in rigid NaDC‐aggregates/AEM system by the coordination which decreases the probability of collision of phosphor with quenchers such as dissolved oxygen molecules and prolongs the lifetime of the phosphor on the triplet state. Long excited‐state lifetimes resulted in great enhancement of Pd‐TCPP phosphorescence. Observations by optical microscope showed that specific fan‐like structures of NaDC were formed under the influence of AEM. Surface tension measurements supported a close interaction between Ca2+ ions and anion aggregates of NaDC with 1:1 stoichiometric ratio. Due to its outstanding RTP behavior in NaDC‐aggregates induced by Ca2+, Pd‐TCPP was used as a RTP probe to detect bovine serum albumin (BSA). A broad linear range from 1.0 × 10−9 to 9.0 × 10−7 g mL−1 was obtained. Detection limit is 2.6 × 10−11 g mL−1, the relative standard deviation (n = 6) is 2.3% for 2.0 × 10−9 g mL−1 BSA.
Being in one's chosen job determines pre‐training attitudes and training outcomes
Authors: Patrick John , Smy Victoria , Tombs Michal , Shelton Katherine
Published: March 2011

The present study introduces a new important variable into a model of training motivation, namely that of being in one's chosen job. Evidence exists that having some control and choice over aspects of training have positive effects on training motivation. We propose that being in one's chosen job will also have such an effect, as it provides trainees with greater autonomy regarding their career progression (e.g., Gagné & Deci, 2005) and aligns their training activity closely with their personal goals (e.g., Locke & Latham, 2002). Pre‐ and post‐training surveys were completed by 232 instructors who were themselves on a military training course. Results confirmed the positive effects of being in one's chosen job on the pre‐training attitudes of self‐efficacy and training motivation with further direct effects on motivation to transfer, and indirect effects on knowledge acquisition and post‐training self‐efficacy. Findings have both theoretical and practical ramifications. Being in one's chosen job should be incorporated into models of training motivation and, whenever possible, employees being re‐deployed should be granted their job preference because this is associated with important positive effects on pre‐training attitudes and motivation to transfer new skills to the work environment.
A SOFC-Based Integrated Gasification Fuel Cell Cycle With CO2 Capture
Authors: Spallina Vincenzo , Romano Matteo C. , Campanari Stefano , Lozza Giovanni
Published: March 2011

The application of solid oxide fuel cells (SOFC) in gasification-based power plants would represent a turning point in the power generation sector, allowing to considerably increase the electric efficiency of coal-fired power stations. Pollutant emissions would also be significantly reduced in integrated gasification fuel cell cycles (IGFC) considering the much lower emissions of conventional pollutants (NOx, CO, SOx, and particulate matter) typical of fuel cell-based systems. In addition, SOFC-based IGFCs appear particularly suited to applications in power plants with CO2 capture. This is evident by considering that SOFCs operate as air separators and partly oxidized fuel exiting the fuel cell does not contain nitrogen from air, such as in conventional oxyfuel processes. The aim of this paper is the thermodynamic analysis of a SOFC-based IGFC with CO2 capture. In the assessed plant, syngas produced in a high efficiency Shell gasifier is used in SOFC modules after heat recovery and cleaning. Anode exhausts, still containing combustible species, are burned with oxygen produced in the air separation unit, also used to generate the oxygen needed in the gasifier; the product gas is cooled down in a heat recovery steam generator before water condensation and CO2 compression. The plant layout is carefully designed to best exploit the heat generated in all the processes and, apart from the fuel cell exotic components, far from industrial state-of-the-art, are not included. Detailed energy and mass balances are presented for a better comprehension of the obtained results.
A Data Filter for Identifying Steady-State Operating Points in Engine Flight Data for Condition Monitoring Applications
Authors: Simon Donald L. , Litt Jonathan S.
Published: March 2011

This paper presents an algorithm that automatically identifies and extracts steady-state engine operating points from engine flight data. It calculates the mean and standard deviation of select parameters contained in the incoming flight data stream. If the standard deviation of the data falls below defined constraints, the engine is assumed to be at a steady-state operating point and the mean measurement data at that point are archived for subsequent condition monitoring purposes. The fundamental design of the steady-state data filter is completely generic and applicable for any dynamic system. Additional domain-specific logic constraints are applied to reduce data outliers and variance within the collected steady-state data. The filter is designed for on-line real-time processing of streaming data as opposed to post-processing of the data in batch mode. Results of applying the steady-state data filter to recorded helicopter engine flight data are shown, demonstrating its utility for engine condition monitoring applications.
Modeling Identification and Control of Peltier Thermoelectic Modules for Telepresence
Authors: Guiatni Mohamed , Kheddar Abderrahmane
Published: March 2011

This research deals with thermal rendering for telepresence applications. We present the modeling and identification of thermo-electric modules (TEMs) to be used either as part of a thermal display or a remote thermal probe. First, TEMs are modeled in steady- and unsteady-state dynamics using recursive nonlinear autoregressive moving average models for both temperature and heat flux. The proposed models are convenient for simulation, control, electronic, and thermal engineering. They allow understanding the functionality of the heat pumps and facilitate the solving of cooling/heating problems without the need for expertise in thermal theory. Then, these models are used in a novel thermal rendering approach that is based on the estimation of the temperature in contact for both the finger and the probed remote object in a telepresence setup. The thermal feedback is provided by a bilateral control between the master (thermal display) and the slave (thermal probe robotic finger). Experimental results validating the models and the proposed thermal rendering scheme are presented and discussed.
Design and Preparation of SOFC Unit Cells Using Scandia-Stabilized Zirconia Electrolyte for Intermediate Temperature Operation
Authors: Park Sung-Chul , Lee Jong-Jin , Lee Seung-Ho , Moon Jooho , Hyun Sang-Hoon
Published: March 2011

A solid oxide fuel cell unit cell based on a scandia-stabilized zirconia (ScSZ) electrolyte for intermediate temperature operation (below 650°C) was manufactured as an anode-supported unit cell via uniaxial pressing, dip-coating, and screen printing methods. The nanocomposite powders used to improve anode performance were synthesized by selectively coating nanosized NiO particles on ScSZ core particles by the Pechini process. Anode-supported ScSZ electrolytes were fabricated by dip-coating a slurry of Ni-ScSZ composite powder on a die-pressed anode pellet, followed by dip-coating of the electrolyte ScSZ slurry. The lanthanum strontium manganite (LSM)-ScSZ cathode and the samarium doped ceria (SDC) interlayer were formed on the anode-supported ScSZ electrolyte using the screen printing method. The lanthanum strontium cobalt ferrite (LSCF)–SDC cathode was also formed on the SDC interlayer. The anode-supported unit cells designed and prepared in this study had a power density of 0.61 W cm−2 at 800°C. Moreover, the unit cell structured by the functional layer and the LSCF cathode demonstrated excellent performance with a power density of 0.49 W cm−2 at 650°C.
A method for robust segmentation of arbitrarily shaped radiopaque structures in cone‐beam CT projections
Authors: Poulsen Per Rugaard , Fledelius Walther , Keall Paul J. , Weiss Elisabeth , Lu Jun , Brackbill Emily , Hugo Geoffrey D.
Published: March 2011

Purpose:

Implanted markers are commonly used in radiotherapy for x‐ray based target localization. The projected marker position in a series of cone‐beam CT (CBCT) projections can be used to estimate the three dimensional (3D) target trajectory during the CBCT acquisition. This has important applications in tumor motion management such as motion inclusive, gating, and tumor tracking strategies. However, for irregularly shaped markers, reliable segmentation is challenged by large variations in the marker shape with projection angle. The purpose of this study was to develop a semiautomated method for robust and reliable segmentation of arbitrarily shaped radiopaque markers in CBCT projections.

Methods:

The segmentation method involved the following three steps: (1) Threshold based segmentation of the marker in three to six selected projections with large angular separation, good marker contrast, and uniform background; (2) construction of a 3D marker model by coalignment and backprojection of the threshold‐based segmentations; and (3) construction of marker templates at all imaging angles by projection of the 3D model and use of these templates for template‐based segmentation. The versatility of the segmentation method was demonstrated by segmentation of the following structures in the projections from two clinical CBCT scans: (1) Three linear fiducial markers (Visicoil) implanted in or near a lung tumor and (2) an artificial cardiac valve in a lung cancer patient.

Results:

Automatic marker segmentation was obtained in more than 99.9% of the cases. The segmentation failed in a few cases where the marker was either close to a structure of similar appearance or hidden behind a dense structure (data cable).

Conclusions:

A robust template‐based method for segmentation of arbitrarily shaped radiopaque markers in CBCT projections was developed.
Developing and validating a risk scoring tool for chlamydia infection among sexual health clinic attendees in Australia: a simple algorithm to identify those at high risk of chlamydia infection
Authors: Wand Handan , Guy Rebecca , Donovan Basil , McNulty Anna
Published: March 2011

Objective

To develop and validate a risk scoring tool to identify those who are at increased risk of chlamydia infection.

Methods

We used demographic data, sexual behaviour information and chlamydia positivity results from more than 45 000 individuals who attended Sydney Sexual Health Centre between 1998 and 2009. Participants were randomly allocated to either the development or internal validation data set. Using logistic regression, we created a prediction model and weighted scoring system using the development data set and calculated the odds ratio of chlamydia positivity for participants in successively higher quintiles of score. The internal validation data set was used to evaluate the performance characteristics of the model for five quintiles of risk scores including population attributable risk, sensitivity and specificity.

Results

In the prediction model, inconsistent condom use, increased number of sexual partners in last 3 months, genital or anal symptoms and presenting to the clinic for sexually transmitted infections screening or being a contact of a sexually transmitted infection case were consistently associated with increased risk of chlamydia positivity in all groups. High scores (upper quintiles) were significantly associated with increased risk of chlamydia infection. A cut-point score of 20 or higher distinguished a increased risk group with a sensitivity of 95%, 67% and 79% among heterosexual men, women and men who have sex with men (MSM), respectively.

Conclusion

The scoring tool may be included as part of a health promotion and/or clinic website to prompt those who are at increased risk of chlamydia infection, which may potentially lead to increased uptake and frequency of testing.
Magnetic resonance spectroscopy in the prediction of early conversion from amnestic mild cognitive impairment to dementia: a prospective cohort study
Authors: Modrego Pedro J , Fayed Nicolas , Sarasa Manuel
Published: March 2011

Background

Mild cognitive impairment (MCI) of an amnestic type is a common condition in older people and highly predictive of Alzheimer's disease (AD). To date, there is no clear consensus regarding the best antecedent biomarker to predict early conversion to AD.

Objective

The aim of the study is to demonstrate that1H magnetic resonance spectroscopy (MRS) of the brain in MCI patients may predict early conversion to dementia within the 2-year period after baseline assessment.

Methods

A cohort of patients fulfilling the criteria of amnestic MCI were enrolled consecutively. At baseline the patients underwent neuropsychological examination, standard blood tests and APOE genotype.1H-MRS (1.5 T) of the brain was carried out by exploring two areas: the posteromedial bilateral parietal lobe and left medial occipital lobe. The patients were followed up to detect conversion to probable AD according to the National Institute of Neurological and Communicative Disorders and Stroke and the Alzheimer's Disease and Related Disorders Association group criteria.

Results

After a 2-year follow-up, 27 (38%) patients converted to AD. The mean N-acetyl-aspartate/creatine (NAA/Cr) ratio in the posteromedial bilateral parietal cortex was 1.38 in converters versus 1.49 in non-converters (p<0.0001). An NAA/Cr ratio equal to or lower than 1.43 in this area predicted conversion to probable AD at 74.1% sensitivity and 83.7% specificity (area under the curve: 0.84; 95% CI 0.73 to 0.92). The cross-validated accuracy of classification was 82%, which reaches 85% when the APOE4 genotype and memory test are included in the analysis. In the left medial occipital lobe, the predictive value was somewhat lower with 85.2% sensitivity and 61.4% specificity (area under the curve: 0.8; 95% CI 0.69 to 0.89). Neither the APOE4 genotype nor leuco-araiosis was predictive of conversion to dementia.

Conclusion

MRS is a valuable biomarker to predict early conversion to dementia in patients with amnestic MCI.
Doctors accessing mental-health services: an exploratory study
Authors: Stanton Josephine , Randal Patte
Published: March 2011

Objective

To develop a more in-depth understanding of how doctors do and do not access mental healthcare from the perspectives of doctors themselves and people they have contact with through the process.

Design

Qualitative methodology was used with semistructured interviews transcribed and analysed using Grounded Theory. Participants were 11 doctors with experience as patients of psychiatrists, four doctor and four non-doctor personal contacts (friends, family and colleagues) and eight treating psychiatrists.

Results

Participants described experiencing unrealistic expectations and a harsh work environment with poor self care and denial and minimisation of signs of mental health difficulties. Doctor contacts described particular difficulty in responding effectively to doctor friends, family and colleagues in need of mental healthcare. In contrast, non-doctor personal contacts were more able to identify and speak about concerns but not necessarily to enable accessing adequate mental-health services.

Conclusions

Three areas with potential to address in supporting doctors' accessing of appropriate healthcare have been identified: (1) processes to enable doctors to maintain high standards of functioning with less use of minimisation and denial; (2) improving the quality and effectiveness of informal doctor-to-doctor conversations about mental-health issues among themselves; (3) role of non-doctor support people in identifying doctors' mental-health needs and enabling their access to mental healthcare. Further research in all these areas has the potential to contribute to improving doctors' access to appropriate mental healthcare and may be of value for the general population.
Feasibility of self-sampling and human papillomavirus testing for cervical cancer screening in First Nation women from Northwest Ontario, Canada: a pilot study
Authors: Zehbe Ingeborg , Moeller Helle , Severini Alberto , Weaver Bruce , Escott Nicholas , Bell Crystal , Crawford Sandra , Bannon Diane , Paavola Natalie
Published: March 2011

Background

The incidence of cervical cancer is up to sixfold higher among First Nation women in Canada than in the general population. This is probably due to lower participation rates in cervical cancer prevention programmes.

Objective

To raise screening participation in this underserved population by launching an alternative approach to (Pap)anicolaou testing in a clinic—namely, vaginal self-sampling followed by human papillomavirus (HPV) diagnostics.

Methods

Good relationships were established with a First Nation community of the Northern Superior region in Northwest Ontario, and then 49 community women, aged 25–59, were recruited, who provided a vaginal self-sample and answered a questionnaire. Frequency distributions and cross-tabulations were used to summarise the data. Associations between categorical variables were assessed using the χ2test of association, or the Goodman–Kruskal γ if both variables had ordered categories. Self-collected samples were tested for integrity and HPV using optimised molecular biological methods.

Results

The majority of participants (87.2%) were amenable to future HPV screening by self-sampling. This finding was independent of age, educational level and a previous history of abnormal Pap tests. Interestingly, the preferred way to learn about sexual health remained through interaction with healthcare professionals. As defined by the presence of a housekeeping gene, self-sample integrity was high (96%). Using polymerase chain reaction-based Luminex typing, the overall HPV positivity was 28.6% (ie, with either a low- or high-risk type) and 16.3% were infected with a high-risk type such as HPV16.

Conclusion

In this pilot study of First Nation women, self-sampling and HPV testing was well received and self-sample quality was excellent. A larger survey to be conducted in other Northern Superior communities in Northwest Ontario will determine whether this approach could become a viable screening strategy for First Nation women.
A survey on self-assessed well-being in a cohort of chronic locked-in syndrome patients: happy majority, miserable minority
Authors: Bruno Marie-Aurélie , Bernheim Jan L , Ledoux Didier , Pellas Frédéric , Demertzi Athena , Laureys Steven
Published: March 2011

Objectives

Locked-in syndrome (LIS) consists of anarthria and quadriplegia while consciousness is preserved. Classically, vertical eye movements or blinking allow coded communication. Given appropriate medical care, patients can survive for decades. We studied the self-reported quality of life in chronic LIS patients.

Design

168 LIS members of the French Association for LIS were invited to answer a questionnaire on medical history, current status and end-of-life issues. They self-assessed their global subjective well-being with the Anamnestic Comparative Self-Assessment (ACSA) scale, whose +5 and −5 anchors were their memories of the best period in their life before LIS and their worst period ever, respectively.

Results

91 patients (54%) responded and 26 were excluded because of missing data on quality of life. 47 patients professed happiness (median ACSA +3) and 18 unhappiness (median ACSA −4). Variables associated with unhappiness included anxiety and dissatisfaction with mobility in the community, recreational activities and recovery of speech production. A longer time in LIS was correlated with happiness. 58% declared they did not wish to be resuscitated in case of cardiac arrest and 7% expressed a wish for euthanasia.

Conclusions

Our data stress the need for extra palliative efforts directed at mobility and recreational activities in LIS and the importance of anxiolytic therapy. Recently affected LIS patients who wish to die should be assured that there is a high chance they will regain a happy meaningful life. End-of-life decisions, including euthanasia, should not be avoided, but a moratorium to allow a steady state to be reached should be proposed.
A randomised controlled trial of cognitive-behavioural therapy for women with problematic menopausal hot flushes: MENOS 2 trial protocol
Authors: Ayers Beverley , Mann Eleanor , Hunter Myra S
Published: March 2011

Objectives

Hot flushes and night sweats (HF/NS) are experienced by 60–70% of menopausal women and are problematic for approximately 20–25%. Potential health risks associated with hormone-replacement therapy (HT) have led to a significant decline in HT use. There is therefore a need for safe, effective and evidence-based alternative treatments for menopausal symptoms. Previous exploratory work suggests that cognitive–behavioural therapy (CBT) is acceptable and effective for women with HF/NS during natural menopause and following breast-cancer treatment. This randomised controlled trial compares the effectiveness of Group CBT and Guided Self-Help CBT with no treatment control in reducing HF/NS Problem Rating and Frequency at post-treatment (main outcome) and at 6 months postrandomisation.

Methods and analysis

120 women, with 10 or more HF/NS a week for a month, are recruited from GP surgeries and the local community of South London. They are randomised to either 4 weeks of Group CBT, 4 weeks guided Self-Help CBT or no treatment control. Participants attend a clinical interview, and complete baseline questionnaire measures of HF/NS Problem Rating and Frequency (primary outcomes), mood, quality of life, self-esteem, hot-flush beliefs and behaviours, optimism and somatic amplification, and undergo 24 h sternal skin conductance monitoring (SCC—physiological measure of HF/NS) (secondary outcomes). Post-treatment measures (SSC, questionnaires and use of medical services) are collected 6–8 weeks later and follow-up measures (questionnaires and a use of medical services measure) at 6 months postrandomisation.

Ethics and dissemination

Ethical registration was granted by King's College London Research Ethics Committee (ref: PNM/08/09-42). All participants provide written informed consent. If treatment is successful, a Group CBT training manual and training sessions for health professionals, and a Self-Help CBT book will be published. Other CBT delivery options will also be examined (including Computerised Self-Help CBT and Group CBT workshops).

Clinical Trial Registration Number

ISRCTN57302613.
Far-red absorbing azodipyrrin dyes — Synthesis, X-ray crystallographic, and spectral characterization of 1,9-diazodipyrrins and their metal complexes
Authors: Li Yan , Dolphin David
Published: March 2011

A series of novel 1,9-diazodipyrrins (4) were readily synthesized by reacting aryldiazonium salts with 5-aryldipyrromethanes under both acidic and basic conditions. The zinc complex of 1,9-diphenylazodipyrrin (5aZn) was confirmed by X-ray crystallographic analysis, and 1,9-diazodipyrrins and their zinc and nickel complexes (5M) were characterized by 1H and 13C NMR, IR, UV–vis, and MS. All of the metal complexes absorb almost all colours of the rainbow; the absorption maximums are >650 nm and the half-band widths are over 100 nm. The fluorescence of the zinc complexes of 1,9-diphenylazodipyrrin (5aZn) and 1,9-di(2-iodophenylazo)dipyrrin (5cZn) were also explored.
Flexible and rigid core molecules in the synthesis of poly(lactic acid) star polymers
Authors: Perry Mitchell R. , Shaver Michael P.
Published: March 2011

This study presents the synthesis and physical characterization of a series of structurally well-defined star-shaped poly(lactic acids). Polymer stars are prepared from a series of multifunctional alcohol cores including flexible polyols pentaerythritol and dipentaerythritol (four-armed and six-armed cores, respectively) and rigid substituted arenes tri(hydroxymethyl)benzene and hexa(hydroxymethyl)benzene. Utilizing a tin(II) octanoate catalyst, arms of 10 monomer units long are built from rac-lactide and l-lactide to form atactic and isotactic star polymers. Polymers were subsequently characterized by means of NMR spectroscopy, gel permeation chromatography, differential scanning calorimetry, and thermogravimetric analysis. Our results support previous work that suggests that the length of the individual arms, not the total molecular weight, correlates to physical characteristics including glass, melt, crystallization, and decomposition temperatures. In addition, differences between core molecules suggest that the chemical nature of the core can significantly alter the physical properties of the star polymer. Trends in crystallization and glass transition temperatures relative to the core used merit further study and correlate closest to the molecular weight and the number of arms emanating from the star core. It is also clear that the rigidity provided by aromatic cores has a significant effect on the melting temperatures of these macromolecules.
The detection of ruthenium chloride clusters by laser desorption ionization-mass spectrometry of RuCl3·3H2O
Authors: Boncheff Alexander G. , Monteiro Mario A.
Published: March 2011

The production of gas-phase singly charged ruthenium chloride anionic complexes by laser desorption ionization of RuCl3·3H2O is reported. The [RuxCly]− clusters could only be detected in the absence of the matrix component in the negative mode. The cluster compositions observed were [RuCl4]−, [RuCl5]−, [Ru2Cl6]−, [Ru2Cl7]−, [Ru3Cl9]−, [Ru4Cl11]−, and [Ru5Cl12]−. With the aid of density functional theory calculations, we proposed feasible structures for each ruthenium chloride cluster, in which Ru–Ru bonds and Cl bridges were a common characteristic.
MINIMAL n-CHARTS WITH FOUR WHITE VERTICES
Authors: ISHIDA SATORU , NAGASE TERUO , SHIMA AKIKO
Published: March 2011

In this paper, we investigate a minimal chart with exactly four white vertices.
KAUFFMAN BRACKET SKEIN MODULE OF THE CONNECTED SUM OF TWO PROJECTIVE SPACES
Authors: MROCZKOWSKI MACIEJ
Published: March 2011

Diagrams and Reidemeister moves for links in a twisted S1-bundle over an unorientable surface are introduced. Using these diagrams, we compute the Kauffman Bracket Skein Module (KBSM) of ℝP3♯ℝP3. In particular, we show that it has torsion. We also present a new computation of the KBSM of S1 × S2 and the lens spaces L(p, 1).
AN UPPER BOUND ON STICK NUMBER OF KNOTS
Authors: HUH YOUNGSIK , OH SEUNGSANG
Published: March 2011

In 1991, Negami found an upper bound on the stick number s(K) of a nontrivial knot K in terms of crossing number c(K) which is s(K) ≤ 2c(K). In this paper we give a new upper bound in terms of arc index, and improve Negami's upper bound to [Formula: see text]. Moreover if K is a nonalternating prime knot, then [Formula: see text].
CONSTRUCTION OF A LATTICE KNOT WHOSE THREE SHADOWS ARE ALL TREES
Authors: KAWAMURA KOEI
Published: March 2011

It is known by few that a trivial knot can be transformed into a lattice knot whose three shadows are all trees (here, three shadows mean the projections of the lattice knot to the directions of ordinary orthogonal axes). Since a knot itself is a loop in the space, this fact may be rather astonishing. It will be interesting to ask whether a non-trivial knot has such a transformation or not. The purpose of this paper is to show that any two-bridge torus knot or link has a transformation into a lattice knot whose three shadows are all trees. The algorithm to construct such a position will be demonstrated.
H(2)-GORDIAN DISTANCE OF KNOTS
Authors: KANENOBU TAIZO
Published: March 2011

An H(2)-move is an unknotting operation of a knot, which is performed by adding a half-twisted band. We define the H(2)-Gordian distance of two knots to be the minimum number of H(2)-moves needed to transform one into the other. We give several methods to estimate the H(2)-Gordian distance of knots. Then we give a table of H(2)-Gordian distances of knots with up to 7 crossings.
ADDENDUM TO: "AN EXPANSION OF THE JONES REPRESENTATION OF GENUS 2 AND THE TORELLI GROUP"
Authors: KASAHARA YASUSHI
Published: March 2011

We observe that the determinant of the representation provides a little restriction for the structure of the graded quotients [Formula: see text] introduced in both [2] and [3] that any one of them does not contain the trivial 1-dimensional summand.
COMBINATORIC MASSEY–MILNOR LINKING THEORY
Authors: HSIEH CHUN-CHUNG
Published: March 2011

In this paper following the scheme of Massey–Milnor invariant theory [C. C. Hsieh, Combinatoric and diagrammatic studies in knot theory J. Knot Theory Ramifications16 (2007) 1235–1253; C. C. Hsieh, Massey-Milnor linking = Chern-Simons-Witten graphs, J. Knot Theory Ramifications17 (2008) 877–903; C. C. Hsieh and S. W. Yang, Chern-Simons-Witten configuration space integrals in knot theory, J. Knot Theory Ramifications14 (2005) 689–711], we studied the first non-vanishing linkings of knot theory in ℝ3 and also derived the combinatorial formulae from which we could read out the invariants directly from the knot diagrams. Though the theme is calculus, the idea comes from perturbative quantum field theory.
GORDIAN DISTANCE AND POLYNOMIAL INVARIANTS
Authors: MIYAZAWA YASUYUKI
Published: March 2011

Some evaluations of the Gordian distance from a knot to another knot are given by using three polynomial invariants called the HOMFLY polynomial, the Jones polynomial and the Q-polynomial. Furthermore, Gordian distances between a lot of pairs of knots are determined.
MULTIVARIABLE HODGE THEORETICAL INVARIANTS OF GERMS OF PLANE CURVES
Authors: CASSOU-NOGUÈS PIERRETTE , LIBGOBER ANATOLY
Published: March 2011

We describe methods for calculation of polytopes of quasiadjunction for plane curve singularities which are invariants giving a Hodge theoretical refinements of the zero sets of multivariable Alexander polynomials. In particular we identify some hyperplanes on which all polynomials in multivariable Bernstein ideal vanish.
SURFACES WITH PULLEYS AND KHOVANOV HOMOLOGY
Authors: AUDOUX B.
Published: March 2011

In this paper, we define surfaces with pulleys which are unions of 1- and 2-dimensional manifolds, glued together on a finite number of ℤ/3ℤ-labeled points of their interiors. Then, by seeing them as cobordisms, we give a refinement of Bar-Natan's geometrical construction of Khovanov homology which can be applied to different notions of refined links as links in I-bundle or braid-like links.
GENUS TWO SMALE–WILLIAMS SOLENOID ATTRACTORS IN 3-MANIFOLDS
Authors: MA JIMING , YU BIN
Published: March 2011

Using alternating Heegaard diagrams, we construct some 3-manifolds which admit diffeomorphisms such that the non-wandering sets of the diffeomorphisms are composed of Smale–Williams solenoid attractors and repellers. An interesting example is the truncated-cube space. In addition, we prove that if the nonwandering set of the diffeomorphism consists of genus two Smale–Williams solenoids, then the Heegaard genus of the closed manifold is at most two.
ON HEEGAARD GENUS, BRIDGE GENUS AND BRAID GENUS FOR A 3-MANIFOLD
Authors: OKAZAKI SHIN'YA
Published: March 2011

We introduce the bridge genus and the braid genus as two kinds of genera of a closed connected orientable 3-manifold, and compare them with the Heegaard genus. We show that for any closed connected orientable 3-manifold, the Heegaard genus is less than or equal to the bridge genus and the bridge genus is less than or equal to the braid genus. We consider four inequalities between these three genera and we construct a 3-manifold which satisfies each one of inequalities. Moreover, we show that there exist infinite many 3-manifolds which satisfy each one of inequalities.
COVERINGS, COMPOSITES AND CABLES OF VIRTUAL STRINGS
Authors: GIBSON ANDREW
Published: March 2011

A virtual string can be defined as an equivalence class of planar diagrams under certain kinds of diagrammatic moves. Virtual strings are related to virtual knots in that a simple operation on a virtual knot diagram produces a diagram for a virtual string. In this paper we consider three operations on a virtual string or virtual strings which produce another virtual string, namely covering, composition and cabling. In particular we study virtual strings unchanged by the covering operation. We also show how the based matrix of a composite virtual string is related to the based matrices of its components, correcting a result by Turaev. Finally we investigate what happens under cabling to some invariants defined by Turaev.
ON REPRESENTATIONS OF 2-BRIDGE KNOT GROUPS IN QUATERNION ALGEBRAS
Authors: HILDEN HUGH M. , LOZANO MARÍA TERESA , MONTESINOS-AMILIBIA JOSÉ MARÍA
Published: March 2011

Representations of two bridge knot groups in the isometry group of some complete Riemannian 3-manifolds as E3 (Euclidean 3-space), H3 (hyperbolic 3-space) and E2, 1 (Minkowski 3-space), using quaternion algebra theory, are studied. We study the different representations of a 2-generator group in which the generators are send to conjugate elements, by analyzing the points of an algebraic variety, that we call the variety of affine c-representations ofG. Each point in this variety corresponds to a representation in the unit group of a quaternion algebra and their affine deformations.
REAL ALGEBRAIC KNOTS OF LOW DEGREE
Authors: BJÖRKLUND JOHAN
Published: March 2011

In this paper, we study rational real algebraic knots in ℝP3. We show that two real rational algebraic knots of degree ≤ 5 are rigidly isotopic if and only if their degrees and encomplexed writhes are equal. We also show that any smooth irreducible knot which admits a plane projection with less than or equal to four crossings has a rational parametrization of degree ≤6. Furthermore an explicit construction of rational knots of a given degree with arbitrary encomplexed writhe (subject to natural restrictions) is presented.
REGULAR HOMOTOPIC DEFORMATION OF COMPACT SURFACE WITH BOUNDARY AND MAPPING CLASS GROUP
Authors: HIROSE SUSUMU , YASUHARA AKIRA
Published: March 2011

A necessary and sufficient algebraic condition for a diffeomorphism over a surface embedded in S3 to be induced by a regular homotopic deformation is discussed, and a formula for the number of signed pass moves needed for this regular homotopy is given.
THE LINK-SYMMETRIC GROUPS OF 2-BRIDGE LINKS
Authors: KADOKAMI TERUHISA
Published: March 2011

We describe the link-symmetric groups of 2-bridge links by Schubert's normal forms and Conway's normal forms. The part of Schubert's normal forms is a collection of well-known facts. However, the part of Conway's normal forms may be new. Moreover, we deal with Conway's normal forms whose entries are even integers.
FACTORIZATION FORMULAS AND COMPUTATIONS OF HIGHER-ORDER ALEXANDER INVARIANTS FOR HOMOLOGICALLY FIBERED KNOTS
Authors: GODA HIROSHI , SAKASAI TAKUYA
Published: March 2011

Homologically fibered knots are knots whose exteriors satisfy the same homological conditions as fibered knots. In our previous paper, we observed that for such a knot, higher-order Alexander invariants defined by Cochran, Harvey, and Friedl are generally factorized into the part of the Magnus matrix and that of a certain Reidemeister torsion, both of which are known as invariants of homology cylinders over a surface. In this paper, we study more details of the invariants and give their concrete calculations after restricting to the case of the invariants associated with metabelian quotients of knot groups. We provide explicit computational results of the invariants for all the 12-crossings non-fibered homologically fibered knots.
RACK SHADOWS AND THEIR INVARIANTS
Authors: CHANG WESLEY , NELSON SAM
Published: March 2011

A rack shadow or rack set is a set X with a rack action by a rack R, analogous to a vector space over a field. We use shadow colorings of classical link diagrams to define enhanced rack counting invariants and show that the enhanced invariants are stronger than unenhanced counting invariants.
PATTERN SELECTION IN AN EPIDEMIC MODEL WITH SELF AND CROSS DIFFUSION
Authors: WANG WEIMING , LIN YEZHI , WANG HAILING , LIU HOUYE , TAN YONGJI
Published: March 2011

In this paper, we have presented Turing pattern selection in a spatial epidemic model with zero-flux boundary conditions, for which we have given a general survey of Hopf and Turing bifurcations, and have derived amplitude equations for the excited modes. Furthermore, we present novel numerical evidence of typical Turing patterns, and find that the model dynamics exhibits complex pattern replication: on increasing the control parameter r, the sequence "H0-hexagons → H0-hexagon-stripe mixtures → stripes → Hπ-hexagon-stripe mixtures → Hπ-hexagons" is observed. This may enrich the research of the pattern formation in diffusive epidemic models.
COMPUTER SIMULATIONS OF PLANT BIODIVERSITY IN STABLE AND UNSTABLE ENVIRONMENTS: A TEST OF THE NEUTRAL BIODIVERSITY THEORY
Authors: HAMMOND SEAN T. , NIKLAS KARL J.
Published: March 2011

The Neutral Biodiversity Theory (NBT) argues that community-level patterns are not determined by trait differences among species, but rather by demographic stochasticity. If true, deterministic patterns of species co-existence, transient or otherwise, should not occur. We tested this critical prediction using a spatially explicit, reiterative algorithm (SERA) that incorporates demographic stochasticity to examine how artificial plant species compete for light and space. An additional level of ecological realism was added by simulating species competition in heterogeneous and disturbed environments. Across 108 simulations, small niche differences influenced interspecific competition and persistence, particularly in spatiotemporally heterogeneous environments. One species re-emerged as the dominant, and the identities of subdominant and rare species remained constant. Although stochastic processes played an important role, the results of these simulations are inconsistent with NBT, i.e., very small niche differences dictated patterns even when all species obey the same simple physical rules.
GRAPH MATCHING A SKELETONIZED THEORETICAL MORPHOSPACE WITH A CLADOGRAM FOR GOMPHONEMOID-CYMBELLOID DIATOMS (BACILLARIOPHYTA)
Authors: PAPPAS JANICE L.
Published: March 2011

A three-dimensional (3D) theoretical morphospace of gomphonemoid and cymbelloid diatoms was skeletonized using concepts from extended Reeb graph analysis and Morse theory. The resultant skeleton tree was matched to a cladogram of the same group of related taxa using adjacency matrices of the trees and ordinated with multidimensional scaling (MDS) of leaf nodes. From this, an unweighted path matrix based on the number of branches between leaf nodes was ordinated to determine degree of matched tree structures. A constrained MDS of the path matrix, weighted by ranked MDS leaf node groups as facets, was used to interpret taxon environmental tolerances and habitat preferences with respect to adaptive value. The methods developed herein provided a way to combine results from morphological and phylogenetic analyses and interpret those results with respect to an aspect of evolutionary process, namely, adaptation.
TRAVELING BEHAVIOR OF A WATER CLUSTER RELEASED FROM A CARBON NANOTUBE
Authors: YU H. Q. , LI Y. F. , LI H. , LIEW K. M.
Published: March 2011

Molecular dynamics simulation is used to observe the traveling behavior of a water cluster released from the interior of single-walled carbon nanotube (SWCNT) to a graphite sheet. The simulation results reveal that there is a need for the water cluster overcoming the energy barrier of the binding energy between the water cluster and the SWCNT to escape from the tube. The water cluster undergoes a three-dimensional motion when released from the SWCNT, due to the effect of the thermal velocity. When encountering the graphite sheet in the forward direction, the x axis impact velocity has much effect on the delivery of the water cluster. The fact that the water cluster is bounced back reduces the possibility of being captured by the graphite sheet, resulting in a decrease in the delivery efficiency of the water cluster. The presence of the electric charges can help the graphite sheet to effectively trap the water cluster. These results have implications for the design and fabrication of novel drug delivery devices.
SYNTHESIS OF CARBON NANOTUBES VIA CATALYTIC CHEMICAL VAPOR DEPOSITION METHOD AND THEIR MODIFICATION WITH PREYSSLER ANION, [NaP5W30O110]14-
Authors: BAMOHARRAM F. F. , AHMADPOUR A. , HERAVI M. M.
Published: March 2011

Multiwalled carbon nanotubes (MWCNTs) were synthesized by catalytic chemical vapor deposition method using Fe/Co catalyst over CaCO3 support and acetylene gas as a carbon precursor in the temperature range of 650–800°C, and were modified with Preyssler anion nanostructures via impregnation method. The existence of nanoheteropolyacid [NaP5W30O110]14- inside the MWCNTs was confirmed by infrared spectroscopy and transmission electron microscopy.
SIMULTANEOUS DESCRIPTION OF STRONG AND WEAK H2 ADSORPTION SITES COEXISTING IN MOFs
Authors: CHA MOON-HYUN , NGUYEN MANH CUONG , CHOI KEUNSU , KIM MINSUNG , IHM JISOON
Published: March 2011

We present a theoretical model capable of identifying multiple adsorption sites in a gas storage material with different binding energies and different amounts of adsorbed molecules. By applying this model to experimental data on the hydrogen storage in MOFs, we extract hydrogen adsorption properties of MOFs with coexisting strong and weak adsorption sites.
Repeated muscle biopsies through a single skin incision do not elicit muscle signaling, but IL-6 mRNA and STAT3 phosphorylation increase in injured muscle
Authors: Guerra Borja , Gómez-Cabrera M. Carmen , Ponce-González Jesús Gustavo , Martinez-Bello Vladimir E. , Guadalupe-Grau Amelia , Santana Alfredo , Sebastia Vicente , Viña Jose , Calbet José A. L.
Published: March 2011

To determine if muscle biopsies can be repeated using a single small (5–6 mm) skin incision without inducing immediate MAPK activation or inflammation in the noninjured areas, the phosphorylation of ERK1/2, p38-MAPK, c-Jun NH2-terminal kinases (JNKs), IκBα, IKKα, and signal transducer and activator of transcription 3 (STAT3) was examined concurrent with IL-6 mRNA in six muscle biopsies obtained from the vastus lateralis of five men. Four biopsies were obtained through the same incision (5–6 mm) from the right leg (taken at 0, 30, 123, and 126 min) and another two each from new incisions performed in the left leg (at 31 and 120 min), while the subjects rested supine. The first three biopsies from the right leg were taken ∼3 cm apart from prebiopsied areas. The last biopsy was obtained from the same point from which the second biopsy was sampled. The three biopsies performed through the same skin incision from noninjured muscle areas showed similar levels of ERK1/2, p38-MAPK, JNK, IKKα, IκBα, and STAT3 phosphorylation and similar IL-6 mRNA content. There were no significant differences in the levels of ERK1/2, p38-MAPK, JNK, IKKα, and IκBα phosphorylation between the mean of the three biopsies obtained from the same incision and the sixth biopsy obtained from an injured area. STAT3 phosphorylation was increased by ∼3.5-fold in the sixth biopsy compared with the mean the three biopsies obtained from the same incision ( P < 0.05), and IL-6 mRNA content was increased by 1.8-fold ( P < 0.05). In summary, repeated muscle biopsies can be performed through a single 5- to 6-mm skin incision without eliciting muscle signaling through cascades responding to cellular stress, inflammation, or muscle damage. STAT3 phosphorylation is an early event in the healing response to muscle injury, probably mediated by the autocrine production of IL-6.
Relationship between performance at different exercise intensities and skeletal muscle characteristics
Authors: Iaia F. Marcello , Perez-Gomez Jorge , Thomassen Martin , Nordsborg Nikolai B. , Hellsten Ylva , Bangsbo Jens
Published: March 2011

The hypothesis investigated whether exercise performance over a broad range of intensities is determined by specific skeletal muscle characteristics. Seven subjects performed 8–10 exhaustive cycle trials at different workloads, ranging from 150 to 700 W (150 min to 20 s). No relationships between the performance times at high and low workloads were observed. A relationship ( P < 0.05) was noticed between the percentage of fast-twitch x fibers and the exercise time at 579 ± 21 W (∼30 s; r2 = 0.88). Capillary-to-fiber-ratio ( r2: 0.58–0.85) was related ( P < 0.05) to exercise time at work intensities ranging from 395 to 270 W (2.5–21 min). Capillary density was correlated ( r2 = 0.68; P < 0.05) with the net rate of plasma K+ accumulation during an ∼3-min bout and was estimated to explain 50–80% ( P < 0.05) of the total variance observed in exercise performances lasting ∼30 s to 3 min. The Na+-K+ pump β1-subunit expression was found to account for 13–34% ( P < 0.05) during exhaustive exercise of ∼1–4 min. In conclusion, exercise performance at different intensities is related to specific physiological variables. A large distribution of fast-twitch x fibers may play a role during very intense efforts, i.e., ∼30 s. Muscle capillaries and the Na+-K+ pump β1-subunit seem to be important determinants for performance during exhaustive high-intensity exercises lasting between 30 s and 4 min.
A method for measuring and modeling the physiological traits causing obstructive sleep apnea
Authors: Wellman Andrew , Eckert Danny J. , Jordan Amy S. , Edwards Bradley A. , Passaglia Chris L. , Jackson Andrew C. , Gautam Shiva , Owens Robert L. , Malhotra Atul , White David P.
Published: March 2011

There is not a clinically available technique for measuring the physiological traits causing obstructive sleep apnea (OSA). Therefore, it is often difficult to determine why an individual has OSA or to what extent the various traits contribute to the development of OSA. In this study, we present a noninvasive method for measuring four important physiological traits causing OSA: 1) pharyngeal anatomy/collapsibility, 2) ventilatory control system gain (loop gain), 3) the ability of the upper airway to dilate/stiffen in response to an increase in ventilatory drive, and 4) arousal threshold. These variables are measured using a single maneuver in which continuous positive airway pressure (CPAP) is dropped from an optimum to various suboptimum pressures for 3- to 5-min intervals during sleep. Each individual's set of traits is entered into a physiological model of OSA that graphically illustrates the relative importance of each trait in that individual. Results from 14 subjects (10 with OSA) are described. Repeatability measurements from separate nights are also presented for four subjects. The measurements and model illustrate the multifactorial nature of OSA pathogenesis and how, in some individuals, small adjustments of one or another trait (which might be achievable with non-CPAP agents) could potentially treat OSA. This technique could conceivably be used clinically to define a patient's physiology and guide therapy based on the traits.