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Introduction The diagnosis of psychogenic nonepileptic seizures (PNES) is a common clinical dilemma. We sought to assess the diagnostic value of four ictal signs commonly used in differentiating PNES from epileptic seizures (ES). Methods We retrospectively reviewed consecutive adult video-electroencephalogram (VEM) studies conducted at a single tertiary epilepsy center between May 2009 and August 2016. Each event was assessed by a blinded rater for the presence of four signs: fluctuating course, head shaking, hip thrusting, and back arching. The final diagnosis of PNES or ES was established for each event based on clinical and VEM characteristics. All ES were pooled regardless of focal or generalized onset. We analyzed the odds ratio of each sign in PNES in comparison to ES with adjustment for repeated measures using logistic regression. Additionally, we calculated the sensitivity, specificity, predictive values, and likelihood ratios of each sign to diagnose PNES. Results A total of 742 events from 140 VEM studies were assessed. Fluctuating course (odds ratio (OR) 37.37, 95% confidence interval (CI) 13.56–102.96, P

Crack assessment relies on the linear elastic or elastic-plastic fracture mechanics that requires calculation of stress intensity factor, K, in the fitness for service codes, such as API 579 and ASME BPVC Section XI. For a surface crack in a cylinder, the K calculation becomes calculating the influence coefficients G0 and G1 of K in those codes. API 579 provided accurate tabular data of G0 and G1 for selected cylinder sizes (t/Ri), crack aspect ratios (a/c), crack depths (a/t), and crack tip locations. Recently, the curve-fit solutions of G0 and G1 were obtained for surface cracks at the deepest and surface points. For an arbitrary cylinder size, however, three-parameter interpolations are still needed to estimate the G0 and G1. To avoid performing the complex interpolation, this paper adopts the state-of-the-art machine learning technology to develop data-driven K solutions based on the tabular data of G0 and G1 given in API 579 for axial outside semi-elliptical surface cracks in thick-wall cylinders at the deepest and surface points. The machine learning method utilizes an artificial neural network (ANN), activation function, and optimal learning algorithm to learn and to determine G0 and G1 as a function of the cylinder size (t/Ri), aspect ratio (a/c), and crack depth (a/t) for axial outside surface cracks at the deepest and surface points. The proposed data-driven solutions of G0 and G1 are validated by available curve-fit solutions for the axial outside surface cracks.

Stress corrosion cracking (SCC) had occurred in early-generation high-level nuclear waste tanks constructed by welding carbon steel. This paper describes an ultrasonic inspection system and its fundamental ability to detect and quantify the length of SCC on thick welded steel plates. The finite element method (FEM) was applied to simulate the welding process to estimate the welding residual stress field. Growth of stress corrosion cracks is driven by crack stress intensities exceeding the subcritical cracking threshold intensity. The subject plate was experimentally inspected with ultrasonic nondestructive evaluation (NDE) techniques to characterize the extent of SCC. The NDE system uses a piezoelectric transducer to generate guided waves in the thick steel plate, and a scanning laser Doppler vibrometer (SLDV) to measure multidimensional time–space wavefield data over a user-defined scanning area in the plate surface. The measured wavefield data can show wave interactions in a localized area in the plate due to the presence of the discontinuities of the SCC. To generate an inspection image that can precisely show the crack’s location and/or the dimension, the wavefield data are further processed to generate inspection image that maps the entire sample plate so the crack can be clearly identified in the plate while its length can be readily estimated. The ultrasonic test results for crack length agree well with the visually estimated length and are close to that predicted by the FEM for cracks in the weld residual stress field.

Background Many studies have shown the benefits of deep hypothermia on cerebral protection during arch surgery; however this has a deleterious effect on endothelial function, coagulation & renal functions. Our aim from this study was to show that we could achieve cerebral protection by using selective antegrade cerebral perfusion (SACP) and mild hypothermia, hence avoiding the side effects of deep hypothermia. Methods In this retrospective analytical study, the computerised database was interrogated retrospectively to identify all patients who underwent full arch or hemi-arch replacement with the utilisation of open distal anastomosis technique. The cases retrieved were operated on between August 2003 and September 2013, in the Lancashire cardiac center, Blackpool Victoria Hospital. The main indication of surgery was based on size criteria. A total of 73 patients were identified for inclusion in the study. All patients had SACP along with a period of lower body circulatory arrest at mild systemic hypothermia. 22 patients including 9 (40.9%) men underwent full arch replacement (Group A) and 51 had hemi-arch replacement which included 43 (66.7%) men (Group B). Results The arch group (Group A) had no neurological complications. In the hemi-arch group (Group B), 2 patients (3.9%) had cerebrovascular events but there were no cases of paraplegia. Temporary hemofiltration was required in 1 patient (4.5%) in Group I and 2 patients (3.9%) in Group II. Further, 2 patients (9.1%) in the arch group and 3(6%) in the hemi-arch group had renal dysfunction not needing dialysis. Mean ICU stay was 2 days (±6.5 days) in the arch group and 1 day (±13.9 days) in the hemi-arch group. Overall there were 4 in-hospital deaths including 2 (9.1%) in the arch group and 2 (3.9%) in the hemi-arch group. There was no significant statistical difference between the two groups. Conclusion The study showed outcomes comparable to other previous larger studies and adds to the available evidence in favour of this approach.

An introduction to the universal algebra approach to Higman–Thompson groups (including Thompson’s group [Formula: see text]) is given, following a series of lectures by Graham Higman in 1973. In these talks, Higman outlined an algorithm for the conjugacy problem; which although essentially correct fails in certain cases, as we show here. A revised and complete version of the algorithm is written out explicitly. From this, we construct an algorithm for the power conjugacy problem in these groups. Python implementations of these algorithms can be found in [26].

SOX8 is an HMG-box transcription factor closely related to SRY and SOX9. Deletion of the gene encoding Sox8 in mice causes reproductive dysfunction but the role of SOX8 in humans is unknown. Here, we show that SOX8 is expressed in the somatic cells of the early developing gonad in the human and influences human sex determination. We identified two individuals with 46, XY disorders/differences in sex development (DSD) and chromosomal rearrangements encompassing the SOX8 locus and a third individual with 46, XY DSD and a missense mutation in the HMG-box of SOX8. In vitro functional assays indicate that this mutation alters the biological activity of the protein. As an emerging body of evidence suggests that DSDs and infertility can have common etiologies, we also analysed SOX8 in a cohort of infertile men (n=274) and two independent cohorts of women with primary ovarian insufficiency (POI; n=153 and n=104). SOX8 mutations were found at increased frequency in oligozoospermic men (3.5%; P < 0.05) and POI (5.06%; P=4.5×10-5) as compared with fertile/normospermic control populations (0.74%). The mutant proteins identified altered SOX8 biological activity as compared with the wild-type protein. These data demonstrate that SOX8 plays an important role in human reproduction and SOX8 mutations contribute to a spectrum of phenotypes including 46, XY DSD, male infertility and 46, XX POI. Fil: Portnoi, Marie France. Inserm; Francia. Sorbonne Université. Faculté de Medecine; Francia. Hôpital Armand Trousseau; Francia Fil: Dumargne, Marie Charlotte. Instituto Pasteur; Francia Fil: Rojo, Sandra. Instituto Pasteur; Francia Fil: Witchel, Selma F.. University of Pittsburgh; Estados Unidos Fil: Duncan, Andrew J.. Great Ormond Street Hospital for Children; Reino Unido Fil: Eozenou, Caroline. Instituto Pasteur; Francia Fil: Bignon Topalovic, Joelle. Instituto Pasteur; Francia Fil: Yatsenko, Svetlana A.. University of Pittsburgh; Estados Unidos Fil: Rajkovic, Aleksandar. University of Pittsburgh; Estados Unidos Fil: Reyes Mugica, Miguel. University of Pittsburgh; Estados Unidos Fil: Almstrup, Kristian. Rigshospitalet; Dinamarca Fil: Fusee, Leila. Instituto Pasteur; Francia Fil: Srivastava, Yogesh. Chinese Academy of Sciences; República de China Fil: Chantot Bastaraud, Sandra. Hôpital Armand Trousseau; Francia Fil: Hyon, Capucine. Hôpital Armand Trousseau; Francia. Inserm; Francia Fil: Louis Sylvestre, Christine. Institut Mutualiste Montsouris; Francia Fil: Validire, Pierre. Institut Mutualiste Montsouris; Francia Fil: de Malleray Pichard, Caroline. Hôpital Cochin; Francia Fil: Ravel, Celia. Centre Hospitalier Universitaire de Rennes; Francia Fil: Christin Maitre, Sophie. Inserm; Francia. Hôpital Saint-Antoine; Francia Fil: Brauner, Raja. Universite de Paris; Francia Fil: Rossetti, Raffaella. Università degli Studi di Milano; Italia. Istituto Auxologico Italiano; Italia Fil: Persani, Luca. Istituto Auxologico Italiano; Italia. Università degli Studi di Milano; Italia Fil: Charreau, Eduardo Hernan. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Biología y Medicina Experimental. Fundación de Instituto de Biología y Medicina Experimental. Instituto de Biología y Medicina Experimental; Argentina. Administracion Nacional de Laboratorios E Institutos de Salud "dr. Carlos G. Malbran". Instituto Nacional de Epidemiologia. Departamento de Investigacion.; Argentina Fil: Dain, Liliana Beatriz. Administracion Nacional de Laboratorios E Institutos de Salud "dr. Carlos G. Malbran". Instituto Nacional de Epidemiologia. Departamento de Investigacion.; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Biología y Medicina Experimental. Fundación de Instituto de Biología y Medicina Experimental. Instituto de Biología y Medicina Experimental; Argentina Fil: Chiauzzi, Violeta Alicia. Consejo Nacional de Investigaciones Científicas y Técnicas. Instituto de Biología y Medicina Experimental. Fundación de Instituto de Biología y Medicina Experimental. Instituto de Biología y Medicina Experimental; Argentina. Administracion Nacional de Laboratorios E Institutos de Salud "dr. Carlos G. Malbran". Instituto Nacional de Epidemiologia. Departamento de Investigacion.; Argentina Fil: Mazen, Inas. National Research Centre ; Egipto Fil: Rouba, Hassan. Institut Pasteur du Maroc; Marruecos Fil: Schluth Bolard, Caroline. Hôpital Femme Mère Enfant; Francia Fil: Mac Gowan, Stuart. University of Dundee; Reino Unido Fil: Mc Lean, W. H. Irwin. University of Dundee; Reino Unido Fil: Patin, Etienne. Instituto Pasteur; Francia Fil: Rajpert De Meyts, Ewa. Rigshospitalet; Dinamarca Fil: Jauch, Ralf. Chinese Academy of Sciences; República de China Fil: Achermann, John C.. Great Ormond Street Hospital for Children; Reino Unido Fil: Siffroi, Jean Pierre. Hôpital Armand Trousseau; Francia Fil: Mc Elreavey, Ken. Instituto Pasteur; Francia Fil: Bashamboo, Anu. Inserm; Francia. Instituto Pasteur; Francia

DAX-1 (NR0B1) and SF-1 (NR5A1) are two nuclear receptor transcription factors that play a key role in human adrenal and reproductive development. Loss of DAX-1 function is classically associated with X-linked adrenal hypoplasia congenita. This condition typically affects boys and presents as primary adrenal insufficiency in early infancy or childhood, hypogonadotropic hypogonadism at puberty and impaired spermatogenesis. Late onset forms of this condition and variant phenotypes are increasingly recognized. In contrast, disruption of SF-1 only rarely causes adrenal insufficiency, usually in combination with testicular dysgenesis. Variants in SF-1/NR5A1 more commonly cause a spectrum of reproductive phenotypes ranging from 46,XY DSD (partial testicular dysgenesis or reduced androgen production) and hypospadias to male factor infertility or primary ovarian insufficiency. Making a specific diagnosis of DAX-1 or SF-1 associated conditions is important for long-term monitoring of endocrine and reproductive function, appropriate genetic counselling for family members, and for providing appropriate informed support for young people.

Background: In humans, the adrenal glands and gonads undergo distinct biological events between 6-10 weeks post conception (wpc), such as testis determination, the onset of steroidogenesis and primordial germ cell development. However, relatively little is currently known about the genetic mechanisms underlying these processes. We therefore aimed to generate a detailed genomic atlas of adrenal and gonad development across these critical stages of human embryonic and fetal development.Methods: RNA was extracted from 53 tissue samples between 6-10 wpc (adrenal, testis, ovary and control). Affymetrix array analysis was performed and differential gene expression was analysed using Bioconductor. A mathematical model was constructed to investigate time-series changes across the dataset. Pathway analysis was performed using ClueGo and cellular localisation of novel factors confirmed using immunohistochemistry.Results: Using this approach, we have identified novel components of adrenal development (e.g.ASB4,NPR3) and confirmed the role ofSRYas the main human testis-determining gene. By mathematical modelling time-series data we have found new genes up-regulated withSOX9in the testis (e.g.CITED1), which may represent components of the testis development pathway. We have shown that testicular steroidogenesis has a distinct onset at around 8 wpc and identified potential novel components in adrenal and testicular steroidogenesis (e.g.MGARP,FOXO4,MAP3K15,GRAMD1B,RMND2), as well as testis biomarkers (e.g.SCUBE1). We have also shown that the developing human ovary expresses distinct subsets of genes (e.g.OR10G9,OR4D5), but enrichment for established biological pathways is limited.Conclusion: This genomic atlas is revealing important novel aspects of human development and new candidate genes for adrenal and reproductive disorders.

Stress corrosion cracking (SCC) may occur when chloride-bearing salts and/or dust deliquesce on the external surface of the spent nuclear fuel (SNF) canister at weld residual stress regions. An SCC growth rate test is developed using instrumented bolt-load compact tension specimens using the American Society for Testing Materials (ASTM) specification E1681 with an experimental apparatus that allows an initially dried salt to deliquesce and infuse naturally to the crack front under temperature and humidity parameters relevant to the canister storage environmental conditions. The shakedown tests were conducted over a range of relative humidity controlled by the guidance in ASTM E104 at 50 °C with salt assemblages of (1) mixture of artificial dust and deliquescent salts (2) a mixture of artificial dust and salt from dehydrated sea water. After five months exposure the specimens were examined for evidence of chloride induced stress corrosion cracking (CISCC) and observations are reported for both salt/dust mixtures. The test specimen and apparatus designs will be modified to enhance the interaction between the deliquescing salt and the crack front for more accurate characterization of the crack growth rate as a function of stress intensity factor, which is an essential input to the determination of in-service inspection frequency of SNF canisters.

The structure of a certain subgroup $S$ of the automorphism group of a partially commutative group (RAAG) $G$ is described in detail: namely the subgroup generated by inversions and elementary transvections. We define admissible subsets of the generators of $G$, and show that $S$ is the subgroup of automorphisms which fix all subgroups $\langle Y\rangle$ of $G$, for all admissible subsets $Y$. A decomposition of $S$ as an iterated tower of semi-direct products in given and the structure of the factors of this decomposition described. The construction allows a presentation of $S$ to be computed, from the commutation graph of $G$., 36 pages, 2 figures

A partially commutative structures are widely used in concurrent computations, robotics and pure algebra. This paper is a short survey of free partially commutative groups and RAAGs.

In this note we give two examples of partially commutative subgroups of partially commutative groups. Our examples are counterexamples to the Extension Graph Conjecture and to the Weakly Chordal Conjecture of Kim and Koberda, \cite{KK}. On the other hand we extend the class of partially commutative groups for which it is known that the Extension Graph Conjecture holds, to include those with commutation graph containing no induced $C_4$ or $P_3$. In the process, some new embeddings of surface groups into partially commutative groups emerge., Comment: 15 pages, 5 figures; to appear in Journal of Algebra

Highlights ► Lin28 proteins regulate micro RNAs and are implicated in germ cell development. ► We assessed LIN28A and LIN28B in the early human ovary and testis. ► Expression of LIN28A increases in the developing ovary between 6 and 9 weeks conception. ► Expression of LIN28B was lower and did not change. ► Alterations in LIN28A were not found in women with primary ovarian insufficiency., Lin28 proteins are emerging as important regulators of microRNAs in endocrine systems. Lin28a regulates primordial germ cell development and puberty timing in mice, whereas the related protein LIN28B is associated with age at menarche in genome-wide association studies in humans. Here, we studied expression of LIN28A and LIN28B in early human gonad development. LIN28A increased in the developing ovary between 6 and 9 weeks post conception, but not in the developing testis. Immunohistochemistry demonstrated LIN28A in peripheral germ cells. LIN28B was expressed at lower levels in both tissues and did not increase with time. As disruption of Lin28a affects germ cell development in mice, LIN28A was considered a candidate gene for primary ovarian insufficiency (POI) in humans. However, no significant changes were found in 50 women studied. These findings show LIN28A is strongly expressed in germ cells during early human ovary development, but disruption of LIN28A is not a common cause of POI.

Smart materials with an in-built ability to repair damage caused by normal wear and tear could prove useful in a wide range of applications. Most healable polymer-based materials so far developed require heating of the damaged area. But Burnworth et al. have now produced materials — in the form of polymer strands linked through metal complexes — that can be mended through exposure to light. The metal complexes in these materials can absorb ultraviolet light that is then converted into heat, which temporarily unlinks the polymer strands for quick and efficient defect healing. In principle, healing can take place in situ and while under load. Polymers with the ability to repair themselves after sustaining damage could extend the lifetimes of materials used in many applications1. Most approaches to healable materials require heating the damaged area2,3,4. Here we present metallosupramolecular polymers that can be mended through exposure to light. They consist of telechelic, rubbery, low-molecular-mass polymers with ligand end groups that are non-covalently linked through metal-ion binding. On exposure to ultraviolet light, the metal–ligand motifs are electronically excited and the absorbed energy is converted into heat. This causes temporary disengagement of the metal–ligand motifs and a concomitant reversible decrease in the polymers’ molecular mass and viscosity5, thereby allowing quick and efficient defect healing. Light can be applied locally to a damage site, so objects can in principle be healed under load. We anticipate that this approach to healable materials, based on supramolecular polymers and a light–heat conversion step, can be applied to a wide range of supramolecular materials that use different chemistries.

Zwitterionomers containing less than 13 mol % zwitterion functionality were synthesized using free radical copolymerization of n-butyl acrylate (nBA) and sulfobetaine monomers. X-ray scattering res...

Highly branched poly(arylene ether sulfone)s with systematically varied degrees of branching and sulfonation were synthesized through oligomeric A2 + B3 methods for application as ionic polymer transducer (IPT) membranes. IPTs are a class of electroactive polymer devices that leverage ionomeric membranes to perform electromechanical transduction as actuators and/or sensors. Synthesis of controlled molecular weight A2 oligomeric polysulfones targeted the global degree of branching (DBglobal) to approximately 1–3% in the absence of gelation. Size exclusion chromatography confirmed molecular weights greater than 20 000 g mol−1 were achieved for linear and branched polysulfones. Increased degree of sulfonation of the A2 oligomers reduced the development of molecular weight in the oligomeric A2 + B3 branching reaction; the formation of tough, flexible, ion-conducting membranes is required for emerging transducer applications. Variation in the DBglobal attained did not affect the thermal transitions or elastic modulus as significantly as changes in the degree of sulfonation. However, an ionic dissociation temperature was detected below the glass transition temperature of the polysulfone matrix and was relatively independent of the degree of sulfonation. Successful synthesis and characterization of these well-defined branched polysulfone ionomers provide a basis for future investigation of polymer topology effects on IPT performance. Copyright © 2009 Society of Chemical Industry

Coenzyme Q(10) is a mobile lipophilic electron carrier located in the inner mitochondrial membrane. Defects of coenzyme Q(10) biosynthesis represent one of the few treatable mitochondrial diseases. We genotyped a patient with primary coenzyme Q(10) deficiency who presented with neonatal lactic acidosis and later developed multisytem disease including intractable seizures, global developmental delay, hypertrophic cardiomyopathy, and renal tubular dysfunction. Cultured skin fibroblasts from the patient had a coenzyme Q(10) biosynthetic rate of 11% of normal controls and accumulated an abnormal metabolite that we believe to be a biosynthetic intermediate. In view of the rarity of coenzyme Q(10) deficiency, we hypothesized that the disease-causing gene might lie in a region of ancestral homozygosity by descent. Data from an Illumina HumanHap550 array were analyzed with BeadStudio software. Sixteen regions of homozygosity1.5 Mb were identified in the affected infant. Two of these regions included the loci of two of 16 candidate genes implicated in human coenzyme Q(10) biosynthesis. Sequence analysis demonstrated a homozygous stop mutation affecting a highly conserved residue of COQ9, leading to the truncation of 75 amino acids. Site-directed mutagenesis targeting the equivalent residue in the yeast Saccharomyces cerevisiae abolished respiratory growth.

Elements of the commutator subgroup of a free group can be presented as values of canonical forms, called Wicks forms. We show that, starting from sufficiently high genus g, there is a sequence of words w(g) which can be presented by f(g) distinct Wicks forms, where f(g)>g!. Moreover we may choose these words w(g) to be square free., 9 pages, 4 figures

In order to investigate the potential involvement of mitochondrial electron transport chain (ETC) dysfunction in myotoxicity associated with 3-hydroxy-3-methylglutaryl coenzyme A (HMG-CoA) reductase inhibitor (statin) treatment, assessment was made of ETC activity and ubiquinone status in two patients experiencing myopathy following treatment with simvastatin (40 mg/day) and cyclosporin (patient 1) and simvastatin (40 mg/day) and itraconazole (patient 2). Analysis of skeletal muscle biopsies revealed a decreased ubiquinone status (77 and 132; reference range: 140-580 pmol/mg) and cytochrome oxidase (complex IV) activity (0.006 and 0.007 reference range: 0.014-0.034). To assess statin treatment in the absence of possible pharmacological interference from cyclosporin or itraconazole, primary astrocytes were cultured with lovastatin (100 microM). Lovastatin treatment resulted in a decrease in ubiquinone (97.9 +/- 14.9; control: 202.9 +/- 18.4 pmol/mg; p < 0.05), and complex IV activity (0.008 +/- 0.001; control: 0.011 +/- 0.001; p < 0.05) relative to control. These data, coupled with the patient findings, indicate a possible association between statin treatment, decreased ubiquinone status, and loss of complex IV activity.

Ionic polymer transducers (IPT) based on electroactive polymers (EAP) display electromechanical coupling that enables breakthroughs in the design of high-performance actuators and sensors. The ion-exchange membrane Nafion remains as the benchmark for a majority of research and development in IPT technology. Advances in IPT performance, elemental understanding of transduction mechanisms, and the development of future technologies (e.g., artificial muscles) are largely due to significant efforts to tailor complementary transducer compositions relative to commercially available Nafion. Current fundamental advances in the synthesis, characterization, and application of tailored ion-containing polymers are reviewed for increased performance, decreased cost, and improved processing of IPTs. Recent attention to the correlation of morphological structure to ion conduction mechanisms has led to new paradigms for performance. Tailoring of ionomeric membranes to isolate material interactions within the composite IPT...

There is a trend to separate Thoracic surgery from the Cardiothoracic surgical divisions. One of the main persuasive argument is the evidence in support of increased resection rate and effective delivery of thoracic surgical services. In such context we reviewed the outcome of thoracic surgical practice in our region where a cardiothoracic surgeon's service was standard.

Some hereditary ataxias are treatable and the insight required for this has come from an in depth knowledge of the phenotypes and clinical biochemistry of the conditions. This has required both fundamental and translational clinical research. Prof John Blass was fortunate to begin his career at what we can now recognise as a golden era for such studies and he worked upon two important conditions; Refsum's disease and Friedreich's ataxia. More recently the mitochondrial encephalomyopathies have been described and similar investigative work has been undertaken upon them. Ubiquinone, CoQ(10), deficiency is the most recently recognised encephalomyopathy and is itself treatable. Though rare, it is becoming increasingly recognised and patients are benefiting from the same scholarly approach to its investigation as was afforded Refsums' disease and Friedreich's ataxia.

We report a patient with relatively mild Leigh syndrome and mitochondrial respiratory chain complex II deficiency caused by a homozygous G555E mutation in the nuclear encoded flavoprotein subunit of succinate dehydrogenase. This mutation has previously been reported in a lethal-infantile presentation of complex II deficiency. Such marked phenotypic heterogeneity, although typical of heteroplasmic mutations in the mitochondrial genome, is unusual for nuclear mutations. Comparable activities and stability of mitochondrial respiratory chain enzymes were demonstrated in both patients, so other reasons for the phenotypic variability are considered.

In a previous paper we investigated the centraliser dimension of groups. In the current paper we study properties of centraliser dimension for the class of free partially commutative groups and, as a corollary, we obtain an efficient algorithm for computation of centraliser dimension in these groups., 30 pages, 5 figures Corrections following the referee's report and correcting mistakes in Section 2

As little is known about the impact of non-dialysis-dependent renal dysfunction on short- and mid-term outcomes following coronary surgery we have conducted a large multi-centre study comparing patients with no history of renal dysfunction to those with preoperative renal dysfunction.Data was prospectively collected on 19,625 consecutive patients undergoing isolated coronary surgery between 1997 and 2003 from four institutions. Sixty-seven patients had a history of dialysis support prior to coronary surgery, and were excluded from the main analysis of the study. The remaining 19,558 patients were divided into two groups based on preoperative serum creatinine level, patients with preoperative renal dysfunction with serum creatinine levels200 micromol/L without dialysis support and control patients with preoperative serum creatinine levels200 micromol/L. Case-mix was accounted for by developing a propensity score, which was the probability of belonging to the non-dialysis-dependent renal dysfunction group, and included in the multivariable analyses.There were 19,172 patients with preoperative serum creatinine levels200 micromol/L and 386 patients with serum creatinine levels200 micromol/L without dialysis support. The propensity score included sex, body mass index, co-morbidity factors (respiratory disease, diabetes, cerebrovascular disease, hypertension, and hypercholesterolemia), ejection fraction, left main stem stenosis, emergency status, prior cardiac surgery, off-pump surgery, and the logistic EuroSCORE. After adjusting for the propensity score, patients with preoperative non-dialysis-dependent renal dysfunction had significantly higher in-hospital mortality (adjusted odds ratio 3.0, p0.001), stroke (adjusted odds ratio 2.0, p = 0.033), atrial arrhythmia (adjusted odds ratio 1.5, p = 0.003), prolonged ventilation (adjusted odds ratio 2.1, p0.001), and post-op stay6 days (adjusted odds ratio 2.6, p0.001). One thousand one hundred and eighty-three (6.1%) deaths occurred during 58,062 patient-years follow-up. After adjusting for the propensity score, the adjusted hazard ratio of mid-term mortality for non-dialysis-dependent renal dysfunction was 2.7 (p0.001).Patients undergoing coronary surgery with non-dialysis-dependent renal dysfunction have significantly increased perioperative morbidity and mortality. Mid-term survival is also significantly reduced at 5-years.

Høyer has given a generalisation of the Deutsch–Jozsa algorithm which uses the Fourier transform on a group G which is (in general) non-Abelian. His algorithm distinguishes between functions which are either perfectly balanced (m-to-one) or constant, with certainty, and using a single quantum query. Here, we show that this algorithm (which we call the Deutsch–Jozsa–Høyer algorithm) can in fact deal with a broader range of promises, which we define in terms of the irreducible representations of G.

Topographical patterns are used to selectively tune the adhesion of polymers. Although nature has provided guidance, relatively little is known of how topographic patterns can be intelligently used not only to enhance adhesion but, more importantly, to tune adhesion. We demonstrate that properly designed, low-aspect-ratio posts can alter adhesion from 20% to 400% the value of conventional adhesion descriptors for nonpatterned interfaces. This control is not related to the magnitude of interfacial area but, rather, to altering the local separation processes at an interface by geometry. We establish general relationships that govern the interaction between material properties, pattern length scales, and the control of adhesion. These relationships provide insight into the mechanisms of adhesion for examples in nature, such as the gecko, while also providing concrete guidance for the future design of "smart" adhesives and coatings with nanoscale patterns.

The HMG-CoA reductase inhibitors, also known as statins, have an enviable safety profile; however, myotoxicity and to a lesser extent hepatotoxicity have been noted in some patients following treatment. Statins target several tissues, depending upon their lipophilicity, where they competitively inhibit HMG-CoA reductase, the rate-limiting enzyme for mevalonic acid synthesis and subsequently cholesterol biosynthesis. HMG-CoA reductase is also the first committed rate-limiting step for the synthesis of a range of other compounds including steroid hormones and ubidecarenone (ubiquinone), otherwise known as coenzyme Q(10) (CoQ(10)). Recent interest has focused on the possible role CoQ(10) deficiency may have in the pathophysiology of the rare adverse effects of statin treatment. Currently, there is insufficient evidence from human studies to link statin therapy unequivocally to pathologically significantly decreased tissue CoQ(10) levels. Although statin treatment has been reported to lower plasma/serum CoQ(10) status, few human studies have assessed tissue CoQ(10) status. The plasma/serum CoQ(10) level is influenced by a number of physiological factors and, therefore, has limited value as a means of assessing intracellular CoQ(10) status. In those limited studies that have assessed the effect of statin treatment upon tissue CoQ(10) levels, none have shown evidence of a fall in CoQ(10) levels. This may reflect the doses of statins used, since many appear to have been used at doses below those recommended for their maximum therapeutic effects. Moreover, the poor bioavailability in those peripheral tissues tested may not reflect the effects the agents are having in liver and muscle, the tissues commonly affected in those patients who do not tolerate statins. This article reviews the biochemistry of CoQ(10), its role in cellular metabolism and the available evidence linking possible CoQ(10) deficiency to statin therapy.

A language-theoretic definition of word hyperbolic semigroup is given, which coincides with the original definition for a group. Word problems of semigroups are also considered.

Formation of nitric oxide (NO), by astrocytes, has been suggested to contribute, via impairment of mitochondrial function, to the neurodegnerative process. Thus co-culture of neuronal cells with NO-generating astrocytes leads to a loss of mitochondrial function, as reflected by diminished activities of complexes IV and II+III. However, such damage may in the first instance be limited due to upregulation of neuronal glutathione metabolism as a result of metabolic trafficking of glutathione from the astrocyte to neurone. Furthermore, exposure of astrocytes to NO leads to increased glutathione metabolism resulting in the preservation of glutathione precursors for neuronal utilization. Failure of glutathione trafficking could render neuronal cells particularly susceptible to NO, leading to cell death. In addition, depletion with time of the nitric oxide synthase cofactor, tetrahydrobiopterin, may result in the astrocytic generation of more potent oxidizing species, which could contribute to the neurodegenerative process.

To the Editor: Aminoglycoside antibiotics are used worldwide to treat gram-negative sepsis. Since these drugs are ototoxic and nephrotoxic, drug levels are closely monitored. However, their effect ...

The main result of this paper establishes invariance under change of generators for automatic structures for monoids (a property that is well known to hold for automatic groups but fails for semigroups). This result is then applied to show that if a free product of two monoids is automatic, then so are both the free factors. Finally, the difference between automatic structures, in terms of monoid generating sets and semigroup generating sets, is discussed.

Coenzyme Q10 (CoQ10), the predominant ubiquinone species in humans, functions as an electron carrier in the mitochondrial electron transport chain (ETC) and as an intracellular antioxidant (1). Although primary CoQ10 deficiency is rare, a profound deficiency in skeletal muscle CoQ10 has been reported in patients with multisystem mitochondrial encephalomyopathies (2)(3). Cardiovascular disease has been associated with a CoQ10 deficiency (4)(5), and it is becoming increasingly apparent that other groups of patients may become CoQ10 deficient, particularly individuals with ataxia (6) and some patients receiving statins (7). When assessing tissue CoQ10 status, we have found that the lack of a commercially available nonphysiologic internal standard (IS) is a major difficulty. Although naturally occurring ubiquinones have been used as ISs in this determination, they are not free from the influence of ubiquinones that might be present in human tissue as the result of dietary contamination (8) or synthesis by microorganisms (9)(10). There is a need, therefore, for an alternative IS that is not influenced by exogenous/endogenous ubiquinones. Di-ethoxy-CoQ10 has been suggested as a nonphysiologic IS to determine CoQ10 (11). In this study we evaluated this IS along with di-propoxy-CoQ10 for their suitability to determine tissue CoQ10. Reference intervals were established for the CoQ10 concentration of skeletal muscle, blood mononuclear cells (MNCs), and plasma. A patient with a suspected CoQ10 deficiency was subsequently identified. Reference intervals were established for the following: (a) , skeletal muscle from 26 patients [mean (SE) age, 24.5 (3.9) years; range, 0.5–59 years; ratio of males to females, 7:6] with no evidence of an ETC deficiency detected in their skeletal muscle biopsies; (b) , MNCs from 17 healthy volunteers and 13 disease controls with no clinical evidence of …

W. A. Bogley and M. A. Gutierrez [2] have recently obtained an eight-term exact homology sequence that relates the integral homology of a quotient group Г/MN, where M and N are normal subgroups of the group Г, to the integral homology of the free product Г/M * Г/N in dimensions ≤3 by means of connecting terms constructed from commutator subgroups of Г, M, N and M ∩ N. In this paper we use the methods of [4] to recover this exact sequence under weaker hypotheses and for coefficients in /q for any non-negative integer q. Further, for q = 0 we extend the sequence by three terms in order to capture the relation between the fourth homology groups.

Cyclic words are equivalence classes of cyclic permutations of ordinary words. When a group is given by a rewriting relation, a rewriting system on cyclic words is induced, which is used to construct algorithms to find minimal length elements of conjugacy classes in the group. These techniques are applied to the universal groups of Stallings pregroups and in particular to free products with amalgamation, HNN-extensions and virtually free groups, to yield simple and intuitive algorithms and proofs of conjugacy criteria., 37 pages, 1 figure, submitted. Changes to introduction

Spelling theorems, a Cohen-Lyndon theorem and a Magnus theorem are proved for one-relator products of arbitrary groups, in cases where the relator is a sufficiently high power.