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Selected AbstractsMyosin light chain kinase colocalizes with nonmuscle myosin IIB in myofibril precursors and sarcomeric Z-lines of cardiomyocytesCYTOSKELETON, Issue 7 2006T. V. Dudnakova Abstract Myosin light chain kinase (MLCK) is a key regulator of various forms of cell motility involving actin and myosin II. MLCK is widely present in vertebrate tissues including the myocardium. However, the role of MLCK in cardiomyocyte function is not known. Previous attempts to gain insight into possible roles and identify potential molecular partners were disappointing and equivocal due to cross reactivity of early antibodies with striated muscle MLCK, which has a different genetic locus and a divergent amino acid sequence from the abovementioned enzyme. Using an immunofluorescence approach and a panel of antibodies directed against MLCK, cytoskeletal, and sarcomeric proteins, we localized MLCK to myofibril precursors and Z-lines of sarcomeres in embryonic and adult cardiomyocytes. The same structures contained nonmuscle myosin IIB implicating this protein as a possible target of MLCK. Our results suggest a role for MLCK in cardiomyocyte differentiation and contraction through regulation of nonmuscle myosin IIB. Cell Motil. Cytoskeleton 2006. © 2006 Wiley-Liss, Inc. [source] Regulation of focal adhesion targeting and inhibitory functions of the FAK related protein FRNK using a novel estrogen receptor "switch"CYTOSKELETON, Issue 2 2002Karen H. Martin Abstract Focal adhesion kinase (FAK) is a regulator of numerous adhesion-dependent processes including cell migration, cell proliferation, and cell survival. The C-terminal domain of FAK, FAK-related nonkinase (FRNK), is autonomously expressed and functions as an inhibitor of FAK signaling. Previous attempts to use FRNK as a tool to dissect FAK signaling have been limited because of an inability to temporally regulate the inhibitory functions of FRNK. In this report, we describe and characterize a conditionally targeted form of FRNK that was created by fusing the hormone-binding domain of the estrogen receptor (ER*) to the C-terminus of FRNK. In the absence of added hormone, FRNK-ER* was diffusely distributed throughout the cytoplasm of cells. Upon addition of hormone, the cytoplasmic pool of FRNK-ER* was rapidly redistributed to focal adhesions. We demonstrate that cells expressing FRNK-ER* show a hormone-dependent decrease in FAK tyrosine phosphorylation and cell migration. Furthermore, when cells expressing of FRNK-ER* were treated with hormone, the cells responded with a dramatic change in cell morphology, suggesting a role for FAK in the regulation of the adhesive properties of focal adhesions. Cell Motil. Cytoskeleton 51:76,88, 2002. © 2002 Wiley-Liss, Inc. [source] Are there general rules governing parasite diversity?DIVERSITY AND DISTRIBUTIONS, Issue 3 2007Small mammalian hosts, gamasid mite assemblages ABSTRACT Parasite biodiversity varies on several scales, and in particular among different host species. Previous attempts at finding relationships between host features and the diversity of the parasite assemblages they harbour have yielded inconsistent results, suggesting strongly that any patterns might be taxon-specific. Here, we examined the potential of three host characteristics (host body mass, basal metabolic rate, and area of the geographical range) as determinants of parasite diversity in one group of ectoparasites, gamasid mites (superfamily Dermanyssoidea), using data from 63 species of small mammalian hosts. Our analyses used three measures of parasite diversity (species richness, the Shannon diversity index, and average taxonomic distinctness), and controlled for sampling effort and phylogenetic influences. Although several significant relationships were observed, they depended entirely on which diversity measure was used, or on which host taxon was investigated (insectivores vs. rodents and lagomorphs). In addition, the present results on patterns of mite diversity were not consistent with those of an earlier study involving roughly the same host taxa and the same biogeographical area, but a different group of ectoparasites, i.e. fleas. Thus, there appears to be no universal determinant of parasite diversity, and associations between host features and parasite diversity probably evolve independently in different host,parasite systems. [source] Role of geometrical dimensions in electrophoresis applications with orthogonal fieldsELECTROPHORESIS, Issue 15 2005Mario A. Oyanader Abstract The role of geometrical dimensions in electrophoresis applications with axial and orthogonal (secondary) electric fields is investigated using a rectangular capillary channel. In particular, the role of the applied orthogonal electrical field in controlling key parameters involved in the effective diffusivity and effective (axial) velocity of the solute is identified. Such mathematically friendly relationships are obtained by applying the method of spatial averaging to the solute species continuity equation; this is accomplished after the role of the capillary geometrical dimensions on the applied electrical field equations has been studied. Moreover, explicit analytical expressions are derived for the effective parameters, i.e., diffusivity and convective velocity as functions of the applied (orthogonal) electric field. Previous attempts (see Sauer et al., 1995) have only led to equations for these parameters that require numerical solution and, therefore, limited the use of such results to practical applications. These may include, for example, the design of separation processes as well as environmental applications such as soil reclamation and wastewater treatment. An illustration of how a secondary electrical field can aid in reducing the optimal separation time is included. [source] Among- and within-population variability in tolerance to cadmium stress in natural populations of Daphnia magna: Implications for ecological risk assessmentENVIRONMENTAL TOXICOLOGY & CHEMISTRY, Issue 5 2002Carlos Barata Abstract Previous attempts to test the hypothesis that laboratory selection of isogenetic populations can produce test organisms with a significantly increased mean tolerance to toxic substances have failed. One possible explanation for such failure is that the tolerance of laboratory populations is largely constrained by their origins (were the source populations composed of tolerant genotypes?). To address this question, among- and within-population variability in stress tolerance was assessed by calculating the variance in individual fitness and longevity across a cadmium gradient (0,10 ,g/L). The study employed Daphnia magna clones from four geographically separate European populations. Results revealed significant differences in tolerance to lethal levels of toxic stress among populations. The distribution of tolerances within two of the studied populations showed high amounts of genetic variation in tolerance. Genetic relationships between tolerance traits and life history performance under nonstressful environments differed among the studied populations. One population showed significant but low costs associated with tolerance, whereas no costs were associated with tolerance in the other population. These results suggest that laboratory selection will favor individuals with high fitness or reproductive performance under optimal laboratory conditions resulting in laboratory populations with similar or lower tolerance to toxic stress than their original field populations. Given that populations can exhibit high levels of genetic variability in tolerance to toxic stress, minimizing genetic diversity in toxicity tests will increase the uncertainty attendant in extrapolating from the lab to the field. [source] The Vps4 C-terminal helix is a critical determinant for assembly and ATPase activity and has elements conserved in other members of the meiotic clade of AAA ATPasesFEBS JOURNAL, Issue 7 2008Parimala R. Vajjhala Sorting of membrane proteins into intralumenal endosomal vesicles, multivesicular body (MVB) sorting, is critical for receptor down regulation, antigen presentation and enveloped virus budding. Vps4 is an AAA ATPase that functions in MVB sorting. Although AAA ATPases are oligomeric, mechanisms that govern Vps4 oligomerization and activity remain elusive. Vps4 has an N-terminal microtubule interacting and trafficking domain required for endosome recruitment, an AAA domain containing the ATPase catalytic site and a , domain, and a C-terminal , helix positioned close to the catalytic site in the 3D structure. Previous attempts to identify the role of the C-terminal helix have been unsuccessful. Here, we show that the C-terminal helix is important for Vps4 assembly and ATPase activity in vitro and function in vivo, but not endosome recruitment or interactions with Vta1 or ESCRT-III. Unlike the , domain, which is also important for Vps4 assembly, the C-terminal helix is not required in vivo for Vps4 homotypic interaction or dominant-negative effects of Vps4,E233Q, carrying a mutation in the ATP hydrolysis site. Vta1 promotes assembly of hybrid complexes comprising Vps4,E233Q and Vps4 lacking an intact C-terminal helix in vitro. Formation of catalytically active hybrid complexes demonstrates an intersubunit catalytic mechanism for Vps4. One end of the C-terminal helix lies in close proximity to the second region of homology (SRH), which is important for assembly and intersubunit catalysis in AAA ATPases. We propose that Vps4 SRH function requires an intact C-terminal helix. Co-evolution of a distinct Vps4 SRH and C-terminal helix in meiotic clade AAA ATPases supports this possibility. [source] The pervasive influence of sampling and methodological artefacts on a macroecological pattern: the abundance,occupancy relationshipGLOBAL ECOLOGY, Issue 4 2008Peter D. Wilson ABSTRACT Aim To investigate the influence of sampling and methodological artefacts on the correlation between abundance and occupancy. Location Global scope. Methods A fixed effects weighted regression model was fitted to standardized effect size for 175 examples of correlations between abundance and occupancy. A regression tree model with standard effect size as the dependent variable was also fitted to the data. Results Standard effect size, and therefore the correlation between abundance and occupancy, was found to be strongly influenced by the type of abundance measure used to characterize the abundance,occupancy relationship. Local mean abundance (also referred to as ecological mean abundance) was primarily responsible for negative correlations. Negative correlations also resulted from a mismatch in the sampling extents of abundance and occupancy measures. Main conclusions The combination of abundance and occupancy measures selected to characterize the abundance,occupancy relationship for a given set of data has a profound impact on the sign of the correlation between the selected measures. Previous attempts to understand the processes giving rise to the pattern represented by the abundance,occupancy relationship have confounded sampling artefacts (e.g. spatial extent of abundance and occupancy information) and methodological artefacts (e.g. combining a truncated abundance measure such as local mean abundance with an untruncated occupancy measure such as proportion of occupied samples). Thus, a revision of the approach currently used to define and evaluate competing explanatory models of the abundance,occupancy relationship appears to be necessary. [source] Optimal clinical trial design using value of information methods with imperfect implementationHEALTH ECONOMICS, Issue 5 2010Andrew R. Willan Abstract Traditional sample size calculations for randomized clinical trials are based on the tests of hypotheses and depend on somewhat arbitrarily chosen factors, such as type I and II errors rates and the smallest clinically important difference. In response to this, many authors have proposed the use of methods based on the value of information as an alternative. Previous attempts have assumed perfect implementation, i.e. if current evidence favors the new intervention and no new information is sought or expected, all future patients will receive it. A framework is proposed to allow for this assumption to be relaxed. The profound effect that this can have on the optimal sample size and expected net gain is illustrated on two recent examples. In addition, a model for assessing the value of implementation strategies is proposed and illustrated. Copyright © 2009 John Wiley & Sons, Ltd. [source] Alpha-1-antitrypsin deficiency associated with panniculitis treated with plasma exchange therapyINTERNATIONAL JOURNAL OF DERMATOLOGY, Issue 9 2004Priscila De Oliveira MD Background, Alpha-1-antitrypsin is the principal serum protease inhibitor. In addition to the well-recognized association with early-onset emphysema and cirrhosis, alpha-1-antitrypsin deficiency may be associated with panniculitis. The treatment of this type of panniculitis presents a significant challenge. Previous attempts using immunosuppressive, anti-inflammatory, and cytotoxic drugs have shown variable results. Aim, To report a case of alpha-1-antitrypsin deficiency-associated panniculitis treated with plasma exchange therapy. Methods, A 23-year-old patient developed painful red nodules on her thighs and buttocks with spontaneous ulceration and discharge of oily fluid. A skin biopsy specimen showed septal and lobular panniculitis. The serum alpha-1-antitrypsin level was 22 mg/dL. She was treated with plasma exchange therapy. Results, Treatment of this patient with plasma exchange therapy led to the control of the cutaneous lesions. Conclusions, Plasma exchange therapy represents an alternative treatment which restores serum and tissue alpha-1-antitrypsin levels. This method is proposed because of its clinical benefits and greater availability. [source] Percutaneous embolization of persistent urinary fistula after partial nephrectomy using N-butyl-2-cyanoacrylateINTERNATIONAL JOURNAL OF UROLOGY, Issue 9 2005GÜVEN ASLAN Abstract Percutaneous closure of a calyceal fistula following partial nephrectomy for kidney cancer was achieved with fistula embolization with n-butyl-2-cyanoacrylate. Previous attempts at closure by conservative and endoscopic means were unsuccessful. Tissue adhesives are useful in the management of persistent urinary leakage after partial nephrectomy. [source] Genetic characterization of Erwinia amylovora strains by amplified fragment length polymorphismJOURNAL OF APPLIED MICROBIOLOGY, Issue 2 2004A. Rico Abstract Aims:,Erwinia amylovora is one of the most important pathogens of pear and apple and is subject to strict quarantine regulations worldwide, although its patterns of dispersal are largely unknown. Previous attempts to fingerprint E. amylovora strains by molecular techniques have detected very little polymorphism because of the high genetic homogeneity of this bacterium. Our aim was to establish and test a typing method to quantify genetic diversity among strains of this plant pathogen. Methods and Results:, Twenty-two strains from different hosts and geographical locations were examined by PCR fingerprinting with four primers and by amplified fragment length polymorphism (AFLP) with four selected combinations of primers with a single base extension. PCR fingerprinting revealed little polymorphism producing the same amplification patterns for 17 strains, while the combined AFLP patterns yielded 78 polymorphic bands (34% of total bands) and allowed the differentiation of all but two strains. Clustering of strains in the resulting dendrogram was not correlated with host, year or country of isolation, and questions previous genealogies based on PFGE patterns. Conclusions:, The AFLP technique allowed the detection of an unprecedented number of genetic markers in E. amylovora and proved to be the most useful tool so far for discriminating among strains of this pathogen. The results obtained in this study strongly suggest the occurrence of multiple introductions of the pathogen in Spain and other European countries. Significance and Impact of the Study:, A major limitation in understanding the ecology of fire blight is the lack of typing techniques with a high power of discrimination. This study demonstrates the high resolution and the usefulness of the AFLP technique to differentiate among E. amylovora strains. [source] Morphometric Criteria for Sexing Juvenile Human Skeletons Using the IliumJOURNAL OF FORENSIC SCIENCES, Issue 2 2008Laura A. Wilson B.Sc. Abstract:, Previous attempts to sex juvenile skeletons have focused on the application of qualitative or semi-quantitative techniques. This study applies a variety of geometric morphometric methods, including eigenshape analysis, to this problem. Six metric criteria for the ilia were tested with the aim of investigating previous ideas concerning sexually diagnostic characters. This study uses 25 ilia from juveniles of known age and sex from Christ Church, Spitalfields, London. Ninety-six percent of juvenile ilia were correctly identified as male or female using the shape of the greater sciatic notch. Identification accuracy is shown to improve with age for several criteria. Males were identified to a higher accuracy than females. Application of geometric techniques improves the understanding of the relationship between age, sex, and shape and the clarity with which these relationships can be quantified. Archaeological and forensic relevance of the results are discussed with recommendations for future application. [source] Silent talker: a new computer-based system for the analysis of facial cues to deceptionAPPLIED COGNITIVE PSYCHOLOGY, Issue 6 2006Janet Rothwell This paper presents the development of a computerised, non-invasive psychological profiling system, ,Silent Talker', for the analysis of non-verbal behaviour. Nonverbal signals hold rich information about mental, behavioural and/or physical states. Previous attempts to extract individual signals and to classify an overall behaviour have been time-consuming, costly, biased, error-prone and complex. Silent Talker overcomes these problems by the use of Artificial Neural Networks. The testing and validation of the system was undertaken by detecting processes associated with ,deception' and ,truth'. In a simulated theft scenario thirty-nine participants ,stole' (or didn't) money, and were interviewed about its location. Silent Talker was able to detect different behaviour patterns indicative of ,deception' and ,truth' significantly above chance. For example, when 15 European men had no prior knowledge of the exact questions, 74% of individual responses (,p,<,0.001) and 80% (,p,=,0.035) of interviews were classified correctly. Copyright © 2006 John Wiley & Sons, Ltd. [source] Subgrouping of fibromyalgia patients on the basis of pressure-pain thresholds and psychological factorsARTHRITIS & RHEUMATISM, Issue 10 2003Thorsten Giesecke Objective Although the American College of Rheumatology (ACR) criteria for fibromyalgia are used to identify individuals with both widespread pain and tenderness, individuals who meet these criteria are not a homogeneous group. Patients differ in their accompanying clinical symptoms, as well as in the relative contributions of biologic, psychological, and cognitive factors to their symptom expression. Therefore, it seems useful to identify subsets of fibromyalgia patients on the basis of which of these factors are present. Previous attempts at identifying subsets have been based solely on psychological and cognitive features. In this study, we attempt to identify patient subsets by incorporating these features as well as the degree of hyperalgesia/tenderness, which is a key neurobiologic feature of this illness. Methods Ninety-seven individuals meeting the ACR criteria for fibromyalgia finished the same battery of self-report and evoked-pain testing. Analyzed variables were obtained from several domains, consisting of 1) mood (evaluated by the Center for Epidemiologic Studies Depression Scale [for depression] and the State-Trait Personality Inventory [for symptoms of trait-related anxiety]), 2) cognition (by the catastrophizing and control of pain subscales of the Coping Strategies Questionnaire), and 3) hyperalgesia/tenderness (by dolorimetry and random pressure-pain applied at suprathreshold values). Cluster analytic procedures were used to distinguish subgroups of fibromyalgia patients based on these domains. Results Three clusters best fit the data. Multivariate analysis of variance (ANOVA) confirmed that each variable was differentiated by the cluster solution (Wilks' , [degrees of freedom 6,89] = 0.123, P < 0.0001), with univariate ANOVAs also indicating significant differences (all P < 0.05). One subgroup of patients (n = 50) was characterized by moderate mood ratings, moderate levels of catastrophizing and perceived control over pain, and low levels of tenderness. A second subgroup (n = 31) displayed significantly elevated values on the mood assessments, the highest values on the catastrophizing subscale, the lowest values for perceived control over pain, and high levels of tenderness. The third group (n = 16) had normal mood ratings, very low levels of catastrophizing, and the highest level of perceived control over pain, but these subjects showed extreme tenderness on evoked-pain testing. Conclusion These data help support the clinical impression that there are distinct subgroups of patients with fibromyalgia. There appears to be a group of fibromyalgia patients who exhibit extreme tenderness but lack any associated psychological/cognitive factors, an intermediate group who display moderate tenderness and have normal mood, and a group in whom mood and cognitive factors may be significantly influencing the symptom report. [source] A Novel Low Temperature Transcutaneous Energy Transfer System Suitable for High Power Implantable Medical Devices: Performance and Validation in SheepARTIFICIAL ORGANS, Issue 5 2010Thushari D. Dissanayake Abstract Transcutaneous energy transfer (TET) systems use magnetic fields to transfer power across the skin without direct electrical connectivity. This offers the prospect of lifetime operation and overcomes risk of infection associated with wires passing through the skin. Previous attempts at this technology have not proved suitable due to poor efficiency, large size, or tissue damage. We have developed a novel approach utilizing frequency control that allows for wide tolerance in the alignment between internal and external coils for coupling variations of 10 to 20 mm, and relatively small size (50 mm diameter, 5 mm thickness). Using a sheep experimental model, the secondary coil was implanted under the skin in six sheep, and the system was operated to deliver a stable power output to a 15 W load continuously over 4 weeks. The maximum surface temperature of the secondary coil increased by a mean value of 3.4 ± 0.4°C (±SEM). The highest absolute mean temperature was 38.3°C. The mean temperature rise 20 mm from the secondary coil was 0.8 ± 0.1°C. The efficiency of the system exceeded 80% across a wide range of coil orientations. Histological analysis revealed no evidence of tissue necrosis or damage after four weeks of operation. We conclude that this technology is able to offer robust transfer of power to implantable devices without excess heating causing tissue damage. [source] Geospatial identification of optimal straw-to-energy conversion sites in the Pacific Northwest,BIOFUELS, BIOPRODUCTS AND BIOREFINING, Issue 4 2010George W. Mueller-Warrant Abstract Previous attempts to develop straw-based bioenergy systems have stumbled at costs of transporting this low-density resource to large-scale, centralized facilities. Success in developing small-scale, distributed technologies (e.g. syngas or pyrolysis bio-oil) that reduce these costs will depend on closely matching system requirements to spatial distribution of available straw. We analyzed straw distribution in the Pacific Northwest to identify optimal sites for facilities ranging from a pilot plant currently under development to larger ones of previous studies. Sites for plants with capacities of 1, 10, or 100 million kg straw y -1 were identified using a ,lowest-hanging-fruit' iterative siting process in which the location of maximum density of straw over an appropriately sized neighborhood was identified, distance from that point necessary to include desired quantity of straw measured, straw assigned to that plant removed from the raster, and the process repeated until all available straw had been assigned. Compared to K-means, our new method sited the first 44% of plants at superior locations in terms of local straw density (i.e. lower transportation costs) and the next 39% at equivalent locations. K-means produced better locations for the final 17% of plants along with superior average results. For the smallest facilities at locations defined by 3-year average available straw density, 1.2 km buffers were adequate to provide straw for the first 10% of plants, with twice that distance sufficient for the first 70%. For the largest plants, 12 km buffers satisfied the first 10% of plants, with 24 km buffers satisfying the first 60%. Buffer distances exceeded 68 km for the final 20% of the largest plants. Siting patterns for the smallest plants were more evenly distributed than larger ones, suggesting that farm-scale technology may be more politically appealing. Smaller plants, however, suffered from higher year-to-year variability in straw supply within pre-defined distances. Published in 2010 by John Wiley & Sons, Ltd. [source] Metabolic engineering of the anaerobic central metabolic pathway in Escherichia coli for the simultaneous anaerobic production of isoamyl acetate and succinic acidBIOTECHNOLOGY PROGRESS, Issue 5 2009Cheryl R. Dittrich Abstract An in vivo method of producing isoamyl acetate and succinate simultaneously has been developed in Escherichia coli to maximize yields of both high value compounds as well as maintain the proper redox balance between NADH and NAD+. Previous attempts at producing the ester isoamyl acetate anaerobically did not produce the compound in high concentrations because of competing pathways and the need for NAD+ regeneration. The objective of this study is to produce succinate as an example of a reduced coproduct to balance the ratio of NADH/NAD+ as a way of maximizing isoamyl acetate production. Because the volatility of the two compounds differs greatly, the two could be easily separated in an industrial setting. An ldhA, adhE double mutant strain (SBS110MG) served as the control strain to test the effect of an additional ackA - pta mutation as found in SBS990MG. Both strains overexpressed the two heterologous genes pyruvate carboxylase and alcohol acetyltransferase (for ester production). The triple mutant SBS990MG was found to produce higher levels of both isoamyl acetate and succinate. At the optimal condition of 25°C, the culture produced 9.4 mM isoamyl acetate and 45.5 mM succinate. SBS990MG produced 36% more ester and over 700% more succinate than SBS110MG. In addition, this study demonstrated that a significantly higher isoamyl acetate concentration can be attained by simultaneously balancing the carbon and cofactor flow; the isoamyl acetate concentration of 9.4 mM is more than seven times higher than an earlier report of about 1.2 mM. © 2009 American Institute of Chemical Engineers Biotechnol. Prog., 2009 [source] Quality Measurement and Contract Design: Lessons from the North American Sugarbeet IndustryCANADIAN JOURNAL OF AGRICULTURAL ECONOMICS, Issue 2 2004Brent Hueth This paper examines contracts used in the North American sugarbeet industry. Though quite similar in many respects, the contracts we study vary across processing firms in the set of quality measures used to condition contract payments to growers. This is somewhat surprising, given the homogeneous nature of the processors' finished product (refined sugar). It seems unlikely that processors differ significantly in how they value the various attributes of a sugarbeet, and such a difference is perhaps the most natural reason to expect variation in the structure of quality incentives across processors. Previous attempts to explain the observed variation in sugarbeet contracts have focused on differences in organizational form across firms. In this paper, we provide an alternative explanation that relies on variation across production regions in growers' ability to control the relevant measures of sugarbeet quality. Les auteurs se penchent sur les contrats utilisés dans l'industrie nord-américaine de la betterave sucrière. Bien qu'ils se ressemblent à maints égards, les contrats examinés varient d'un transformateur à l'autre quant au jeu de paramètres servant àévaluer la qualité du produit et à déterminer les sommes qu'on versera au producteur. La chose est surprenante étant donné le caractère homogène du produit fini (sucre raffiné). Il est peu probable que les transformateurs recourent à des méthodes fort différentes pour évaluer les paramètres de la betterave. Or, ce facteur constituerait normalement la raison la plus plausible pour expliquer la variation des incitatifs auxquels recourent les transformateurs Antérieurement, on a tenté d'expliquer les écarts relevés dans les contrats par les différences dans l'organisation des entreprises. L'article que voici propose une autre explication s'appuyant sur la compétence variable des producteurs à respecter les critères de qualité de la betterave sucrière selon la région. [source] Phylogeny of the sea spiders (Arthropoda, Pycnogonida) based on direct optimization of six loci and morphologyCLADISTICS, Issue 3 2007Claudia P. Arango Higher-level phylogenetics of Pycnogonida has been discussed for many decades but scarcely studied from a cladistic perspective. Traditional taxonomic classifications are yet to be tested and affinities among families and genera are not well understood. Pycnogonida includes more than 1300 species described, but no systematic revisions at any level are available. Previous attempts to propose a phylogeny of the sea spiders were limited in characters and taxon sampling, therefore not allowing a robust test of relationships among lineages. Herein, we present the first comprehensive phylogenetic analysis of the Pycnogonida based on a total evidence approach and Direct Optimization. Sixty-three pycnogonid species representing all families including fossil taxa were included. For most of the extant taxa more than 6 kb of nuclear and mitochondrial DNA and 78 morphological characters were scored. The most parsimonious hypotheses obtained in equally weighted total evidence analyses show the two most diverse families Ammotheidae and Callipallenidae to be non-monophyletic. Austrodecidae + Colossendeidae + Pycnogonidae are in the basal most clade, these are morphologically diverse groups of species mostly found in cold waters. The raising of the family Pallenopsidae is supported, while Eurycyde and Ascorhynchus are definitely separated from Ammotheidae. The four fossil taxa are grouped within living Pycnogonida, instead of being an early derived clade. This phylogeny represents a solid framework to work towards the understanding of pycnogonid systematics, providing a data set and a testable hypothesis that indicate those clades that need severe testing, especially some of the deep nodes of the pycnogonid tree and the relationships of ammotheid and callipallenid forms. The inclusion of more rare taxa and additional sources of evidence are necessary for a phylogenetic classification of the Pycnogonida. © The Willi Hennig Society 2006. [source] The phylogeny of the Histeroidea (Coleoptera: Staphyliniformia)CLADISTICS, Issue 4 2002Michael S. Caterino For its size (ca. 4000 species) the Histeridae is one of the most ecologically and morphologically diverse families of beetles. Its mostly predaceous members occupy a wide variety of habitats for which their morphologies may be highly modified. Previous attempts to resolve the phylogeny of the family based on morphological data have left many difficult issues unresolved. This study is the first to utilize either larval or molecular (18S rDNA) data in combination with adult morphology in an attempt to resolve these issues. We compare the performance of optimization alignment with a fixed positional homology approach, over a range of parameter space. Optimizing alignment parameters for combined analyses of 18S and morphology for both approaches resulted in very similar topologies. Contrary to previous hypotheses which held the cylindrical, subcortical forms of the family (e.g., Niponius, Trypanaeus, Trypeticus) to be the most primitive, our analyses find these to be highly specialized forms derived from within other more generalized taxa. Basal lineages within the family instead include Onthophilus, Anapleus, and Dendrophilus, all of which are ovoid, mainly generalist forms. [source] Acromioclavicular joint cyst formationCLINICAL ANATOMY, Issue 2 2010Andrew D. Hiller Abstract Acromioclavicular joint (ACJ) cysts are an uncommon and unusual sequela associated with shoulder pathophysiology. The majority of literature on ACJ cysts consists of individual case reports with no definitive literature review currently available. In addition to a comprehensive literature review, four clinical cases are presented in this report. First described by Craig (1984), a total of 41 cases have been previously reported in the literature. Of these cases, five occurred with the rotator cuff musculature intact. The remaining 36 cases of ACJ cysts occurred in patients with a complete tear/avulsion of the rotator cuff. Previous attempts at compiling a complete record of all reported cases have combined several distinct conditions into a single category. This article presents two distinct etiologies for the pathogenesis of ACJ cyst formation. In the presence of an intact rotator cuff, a Type 1 cyst can form superficially and be limited to the ACJ. Following a massive or traumatic tear of the rotator cuff, mechanical instability of the humeral head can cause a deterioration of the inferior acromioclavicular capsule (cuff tear arthropathy) and an overproduction of synovial fluid. Overtime, a "geyser" of fluid can form between the glenohumeral and the ACJ, forming a Type 2 cyst. This differentiation and categorization is essential for appropriate classification and treatment. Clin. Anat. 23:145,152, 2010. © 2010 Wiley-Liss, Inc. [source] The Efficacy of EMLA versus ELA-Max for Pain Relief in Medium-Depth Chemical Peeling: A Clinical and Histopathologic EvaluationDERMATOLOGIC SURGERY, Issue 1 2000Robert A. Koppel MD Background. Medium-depth chemical peels are an effective and popular treatment for actinic damage, fine wrinkles, and pigmentary dyschromias. However, they are also uncomfortable. A previous attempt to study the effectiveness of a topical anesthetic gel in 35% trichloroacetic acid (TCA) peeling found a reduction in discomfort but an increased depth of penetration and delayed healing. Objective. To evaluate both the efficacy of two topical anesthetic agents in medium-depth combination peeling as well as the histologic result from chemical peeling combined with topical anesthesia. Method. Seventy percent glycolic acid (GA) was applied to the entire face of 10 patients and diluted with water after 2 minutes. This was followed by the sequential application of EMLA cream (lidocaine 2.5% and prilocaine 2.5%), ELA-Max cream (lidocaine 4%), and placebo to selected areas on the face for 30 minutes without occlusion. These agents were then removed and 35% TCA was applied to the entire face. The level of discomfort felt by the patients during the TCA peel was recorded, clinical photographs were taken, and bilateral preauricular biopsies were performed at baseline, 48 hours, and 90 days postoperatively. Results. Clinically there was a statistically significant decrease in pain felt during the 70% GA-35% TCA peel with topical anesthesia when compared to the control. There was no statistically significant difference in efficacy between EMLA and ELA-Max. There was also no difference in either the clinical or the histopathologic appearance between the medium-depth peel combined with topical anesthesia and the medium-depth peel with control. Conclusion. Both EMLA and ELA-Max decrease the discomfort felt during medium-depth combination chemical peeling without influencing either the clinical or the histopathologic result. [source] Do biotic interactions shape both sides of the humped-back model of species richness in plant communities?ECOLOGY LETTERS, Issue 7 2006Richard Michalet Abstract A humped-back relationship between species richness and community biomass has frequently been observed in plant communities, at both local and regional scales, although often improperly called a productivity,diversity relationship. Explanations for this relationship have emphasized the role of competitive exclusion, probably because at the time when the relationship was first examined, competition was considered to be the significant biotic filter structuring plant communities. However, over the last 15 years there has been a renewed interest in facilitation and this research has shown a clear link between the role of facilitation in structuring communities and both community biomass and the severity of the environment. Although facilitation may enlarge the realized niche of species and increase community richness in stressful environments, there has only been one previous attempt to revisit the humped-back model of species richness and to include facilitative processes. However, to date, no model has explored whether biotic interactions can potentially shape both sides of the humped-back model for species richness commonly detected in plant communities. Here, we propose a revision of Grime's original model that incorporates a new understanding of the role of facilitative interactions in plant communities. In this revised model, facilitation promotes diversity at medium to high environmental severity levels, by expanding the realized niche of stress-intolerant competitive species into harsh physical conditions. However, when environmental conditions become extremely severe the positive effects of the benefactors wane (as supported by recent research on facilitative interactions in extremely severe environments) and diversity is reduced. Conversely, with decreasing stress along the biomass gradient, facilitation decreases because stress-intolerant species become able to exist away from the canopy of the stress-tolerant species (as proposed by facilitation theory). At the same time competition increases for stress-tolerant species, reducing diversity in the most benign conditions (as proposed by models of competition theory). In this way our inclusion of facilitation into the classic model of plant species diversity and community biomass generates a more powerful and richer predictive framework for understanding the role of plant interactions in changing diversity. We then use our revised model to explain both the observed discrepancies between natural patterns of species richness and community biomass and the results of experimental studies of the impact of biodiversity on the productivity of herbaceous communities. It is clear that explicit consideration of concurrent changes in stress-tolerant and competitive species enhances our capacity to explain and interpret patterns in plant community diversity with respect to environmental severity. [source] A Genetic Approach to Detecting Clusters in Point Data SetsGEOGRAPHICAL ANALYSIS, Issue 3 2005Jamison Conley Spatial analysis techniques are widely used throughout geography. However, as the size of geographic data sets increases exponentially, limitations to the traditional methods of spatial analysis become apparent. To overcome some of these limitations, many algorithms for exploratory spatial analysis have been developed. This article presents both a new cluster detection method based on a genetic algorithm, and Programs for Cluster Detection, a toolkit application containing the new method as well as implementations of three established methods: Openshaw's Geographical Analysis Machine (GAM), case point-centered searching (proposed by Besag and Newell), and randomized GAM (proposed by Fotheringham and Zhan). We compare the effectiveness of cluster detection and the runtime performance of these four methods and Kulldorf's spatial scan statistic on a synthetic point data set simulating incidence of a rare disease among a spatially variable background population. The proposed method has faster average running times than the other methods and significantly reduces overreporting of the underlying clusters, thus reducing the user's postprocessing burden. Therefore, the proposed method improves upon previous methods for automated cluster detection. The results of our method are also compared with those of Map Explorer (MAPEX), a previous attempt to develop a genetic algorithm for cluster detection. The results of these comparisons indicate that our method overcomes many of the problems faced by MAPEX, thus, we believe, establishing that genetic algorithms can indeed offer a viable approach to cluster detection. [source] Do consumption expenditures depend on the household's relative position in the income distribution?INTERNATIONAL JOURNAL OF CONSUMER STUDIES, Issue 1 2002Mohamed Abdel-Ghany Abstract Even though the permanent income and relative income hypotheses have been introduced in past research to explain consumer behaviour, no previous attempt was undertaken to integrate them in one model. In this article, the hypotheses were synthesized into a single model. The model was empirically tested using data from the 1996 Canadian Family Expenditure Survey. The results indicate that household consumption behaviour is generally explained by both hypotheses when integrated into one model, contrary to previously treating them as mutually exclusive hypotheses. [source] Toxicology and Circumstances of Completed Suicide by Means Other than Overdose,JOURNAL OF FORENSIC SCIENCES, Issue 2 2009Shane Darke Ph.D. Abstract:, To determine the prevalence and circumstances of psychoactive substances amongst nonoverdose completed suicide, 1436 consecutive cases autopsied at the NSW Department of Forensic Medicine over the period 1/1/1997,12/31/2006 were analyzed. Substances were detected in 67.2% of cases, and illicit drugs in 20.1%. Alcohol was present in 40.6% of cases. Males were more likely to be positive for alcohol, cannabis, and psychostimulants, and females for pharmaceuticals. Illicits were associated with younger age. Alcohol was most prominent amongst toxicity cases, as were opioids, psychostimulants amongst gunshot cases, and pharmaceuticals amongst drownings. Cases in which drug and alcohol histories were noted were more likely to have a substance detected. Alcohol was more common where a suicide note was left and where relationship problems were involved. Pharmaceuticals were more common where a previous attempt was noted. Licit and illicit substances are strongly associated with suicide, even when the method does not involve drug overdose. [source] Characterization of microsatellite loci in the endangered species of fern Marsilea strigosa Willd. (Marsileaceae, Pteridophyta)MOLECULAR ECOLOGY RESOURCES, Issue 1-2 2001R. Vitalis Abstract Absence of enzymatic polymorphism in the endangered species of fern Marsilea strigosa prompted us to develop microsatellite loci in this species. We used an enriched partial genomic library, from which six polymorphic microsatellite loci were obtained. From a previous attempt to develop microsatellite markers with standard techniques, a single long and polymorphic locus was obtained. This highlights the benefits from using enrichment techniques in those species where microsatellite loci may be rare in the genome. [source] Australia's Quest to Enrich Uranium and the Whitlam Government's Loans AffairAUSTRALIAN JOURNAL OF POLITICS AND HISTORY, Issue 4 2008Wayne Reynolds The renewed debate about Australia enriching uranium raises issues associated with a previous attempt thirty-five years ago. The Atomic Energy Commission hatched plans in the mid-1960s to position Australia as a supplier of enriched fuel, especially to the Japanese market. This would be done using centrifuge technology, a cheaper and more efficient method than that used by the United States. That fact, along with concerns in Washington to restrict the proliferation of nuclear weapons, led to opposition to rival enrichment programs. Whitlam and Connor miscalculated here. Ratifying the Nuclear Non-proliferation Treaty was not enough to stay opposition to raising a loan designed mainly to give Australia an enrichment program. [source] A Prospective Comparison of Ultrasound-guided and Blindly Placed Radial Arterial CathetersACADEMIC EMERGENCY MEDICINE, Issue 12 2006Stephen Shiver MD Abstract Background Arterial cannulation for continuous blood-pressure measurement and frequent arterial-blood sampling commonly are required in critically ill patients. Objectives To compare ultrasound (US)-guided versus traditional palpation placement of arterial lines for time to placement, number of attempts, sites used, and complications. Methods This was a prospective, randomized interventional study at a Level 1 academic urban emergency department with an annual census of 78,000 patients. Patients were randomized to either palpation or US-guided groups. Inclusion criteria were any adult patient who required an arterial line according to the treating attending. Patients who had previous attempts at an arterial line during the visit, or who could not be randomized because of time constraints, were excluded. Enrollment was on a convenience basis, during hours worked by researchers over a six-month period. Patients in either group who had three failed attempts were rescued with the other technique for patient comfort. Statistical analysis included Fisher's exact, Mann-Whitney, and Student's t-tests. Results Sixty patients were enrolled, with 30 patients randomized to each group. Patients randomized to the US group had a shorter time required for arterial line placement (107 vs. 314 seconds; difference, 207 seconds; p = 0.0004), fewer placement attempts (1.2 vs. 2.2; difference, 1; p = 0.001), and fewer sites required for successful line placement (1.1 vs. 1.6; difference, 0.5; p = 0.001), as compared with the palpation group. Conclusions In this study, US guidance for arterial cannulation was successful more frequently and it took less time to establish the arterial line as compared with the palpation method. [source] Behavioural treatment of urinary incontinence and encopresis in children with learning disabilities: transfer of stimulus controlDEVELOPMENTAL MEDICINE & CHILD NEUROLOGY, Issue 4 2000Linda Smith MAMSc Clinical Psychologist Urinary and faecal incontinence present a considerable problem in people with learning disabilities, despite the general effectiveness of behavioural techniques in continence training. Children with learning disabilities and obsessional behaviour may be particularly resistant to toilet training, even where relatively cognitively able, and often despite a substantial degree of control over their eliminatory functions. Their resistance may be more appropriately regarded as a challenging behaviour and their incontinence better explained by factors other than a simple failure to learn. A 'stimulus-control'hypothesis proposes that the child's nappy (diaper) /potty/underwear has developed strong stimulus control over the elimination response. This report describes three case studies in which treatment-resistant children, aged between 8 and 12 years, with mild or moderate learning disabilities, were successfully treated for nappy-dependent nocturnal encopresis or diurnal urinary incontinence. The children were routine case referrals for whom previous attempts to train bowel or bladder control had failed. Behavioural techniques, such as 'shaping'(gradually increasing the proximity to the toilet),,fading'(reducing the presence of the nappy), and rewards for eliminating, effected successful transfer of stimulus control over elimination from nappy to toilet. Treatment times varied, depending on the degree of the child's obsession and resistance to change. [source] | |||||||||||||||||||||||||||||||||||||