253 resultados para parallel patterns
Resumo:
The shape of alliance processes over the course of psychotherapy has already been studied in several process-outcome studies on very brief psychotherapy. The present study applies the shape-of-change methodology to short-term dynamic psychotherapies and complements this method with hierarchical linear modeling. A total of 50 psychotherapies of up to 40 sessions were included. Alliance was measured at the end of each session. The results indicate that a linear progression model is most adequate. Three main patterns were found: stable, linear, and quadratic growth. The linear growth pattern, along with the slope parameter, was related to treatment outcome. This study sheds additional light on alliance process research, underscores the importance of linear alliance progression for outcome, and also fosters a better understanding of its limitations.
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Adapted filamentous pathogens such as the oomycetes Hyaloperonospora arabidopsidis (Hpa) and Phytophthora infestans (Pi) project specialized hyphae, the haustoria, inside living host cells for the suppression of host defence and acquisition of nutrients. Accommodation of haustoria requires reorganization of the host cell and the biogenesis of a novel host cell membrane, the extrahaustorial membrane (EHM), which envelops the haustorium separating the host cell from the pathogen. Here, we applied live-cell imaging of fluorescent-tagged proteins labelling a variety of membrane compartments and investigated the subcellular changes associated with accommodating oomycete haustoria in Arabidopsis and N. benthamiana. Plasma membrane-resident proteins differentially localized to the EHM. Likewise, secretory vesicles and endosomal compartments surrounded Hpa and Pi haustoria revealing differences between these two oomycetes, and suggesting a role for vesicle trafficking pathways for the pathogen-controlled biogenesis of the EHM. The latter is supported by enhanced susceptibility of mutants in endosome-mediated trafficking regulators. These observations point at host subcellular defences and specialization of the EHM in a pathogen-specific manner. Defence-associated haustorial encasements, a double-layered membrane that grows around mature haustoria, were frequently observed in Hpa interactions. Intriguingly, all tested plant proteins accumulated at Hpa haustorial encasements suggesting the general recruitment of default vesicle trafficking pathways to defend pathogen access. Altogether, our results show common requirements of subcellular changes associated with oomycete biotrophy, and highlight differences between two oomycete pathogens in reprogramming host cell vesicle trafficking for haustoria accommodation. This provides a framework for further dissection of the pathogen-triggered reprogramming of host subcellular changes.
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BACKGROUND: Tests for recent infections (TRIs) are important for HIV surveillance. We have shown that a patient's antibody pattern in a confirmatory line immunoassay (Inno-Lia) also yields information on time since infection. We have published algorithms which, with a certain sensitivity and specificity, distinguish between incident (< = 12 months) and older infection. In order to use these algorithms like other TRIs, i.e., based on their windows, we now determined their window periods. METHODS: We classified Inno-Lia results of 527 treatment-naïve patients with HIV-1 infection < = 12 months according to incidence by 25 algorithms. The time after which all infections were ruled older, i.e. the algorithm's window, was determined by linear regression of the proportion ruled incident in dependence of time since infection. Window-based incident infection rates (IIR) were determined utilizing the relationship 'Prevalence = Incidence x Duration' in four annual cohorts of HIV-1 notifications. Results were compared to performance-based IIR also derived from Inno-Lia results, but utilizing the relationship 'incident = true incident + false incident' and also to the IIR derived from the BED incidence assay. RESULTS: Window periods varied between 45.8 and 130.1 days and correlated well with the algorithms' diagnostic sensitivity (R(2) = 0.962; P<0.0001). Among the 25 algorithms, the mean window-based IIR among the 748 notifications of 2005/06 was 0.457 compared to 0.453 obtained for performance-based IIR with a model not correcting for selection bias. Evaluation of BED results using a window of 153 days yielded an IIR of 0.669. Window-based IIR and performance-based IIR increased by 22.4% and respectively 30.6% in 2008, while 2009 and 2010 showed a return to baseline for both methods. CONCLUSIONS: IIR estimations by window- and performance-based evaluations of Inno-Lia algorithm results were similar and can be used together to assess IIR changes between annual HIV notification cohorts.
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Two different approaches currently prevail for predicting spatial patterns of species assemblages. The first approach (macroecological modelling, MEM) focuses directly on realised properties of species assemblages, whereas the second approach (stacked species distribution modelling, S-SDM) starts with constituent species to approximate assemblage properties. Here, we propose to unify the two approaches in a single 'spatially-explicit species assemblage modelling' (SESAM) framework. This framework uses relevant species source pool designations, macroecological factors, and ecological assembly rules to constrain predictions of the richness and composition of species assemblages obtained by stacking predictions of individual species distributions. We believe that such a framework could prove useful in many theoretical and applied disciplines of ecology and evolution, both for improving our basic understanding of species assembly across spatio-temporal scales and for anticipating expected consequences of local, regional or global environmental changes. In this paper, we propose such a framework and call for further developments and testing across a broad range of community types in a variety of environments.
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This study intended to compare bone density and architecture in three groups of women: young women with anorexia nervosa (AN), an age-matched control group of young women, and healthy late postmenopausal women. Three-dimensional peripheral quantitative high resolution computed-tomography (HR-pQCT) at the ultradistal radius, a technology providing measures of cortical and trabecular bone density and microarchitecture, was performed in the three cohorts. Thirty-six women with AN aged 18-30years (mean duration of AN: 5.8years), 83 healthy late postmenopausal women aged 70-81 as well as 30 age-matched healthy young women were assessed. The overall cortical and trabecular bone density (D100), the absolute thickness of the cortical bone (CTh), and the absolute number of trabecules per area (TbN) were significantly lower in AN patients compared with healthy young women. The absolute number of trabecules per area (TbN) in AN and postmenopausal women was similar, but significantly lower than in healthy young women. The comparison between AN patients and post-menopausal women is of interest because the latter reach bone peak mass around the middle of the fertile age span whereas the former usually lose bone before reaching optimal bone density and structure. This study shows that bone mineral density and bone compacta thickness in AN are lower than those in controls but still higher than those in postmenopause. Bone compacta density in AN is similar as in controls. However, bone inner structure in AN is degraded to a similar extent as in postmenopause. This last finding is particularly troubling.
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DNA that survives in museum specimens, bones and other tissues recovered by archaeologists is invariably fragmented and chemically modified. The extent to which such modifications accumulate over time is largely unknown but could potentially be used to differentiate between endogenous old DNA and present-day DNA contaminating specimens and experiments. Here we examine mitochondrial DNA sequences from tissue remains that vary in age between 18 and 60,000 years with respect to three molecular features: fragment length, base composition at strand breaks, and apparent C to T substitutions. We find that fragment length does not decrease consistently over time and that strand breaks occur preferentially before purine residues by what may be at least two different molecular mechanisms that are not yet understood. In contrast, the frequency of apparent C to T substitutions towards the 5'-ends of molecules tends to increase over time. These nucleotide misincorporations are thus a useful tool to distinguish recent from ancient DNA sources in specimens that have not been subjected to unusual or harsh treatments.
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PURPOSE: Most existing methods for accelerated parallel imaging in MRI require additional data, which are used to derive information about the sensitivity profile of each radiofrequency (RF) channel. In this work, a method is presented to avoid the acquisition of separate coil calibration data for accelerated Cartesian trajectories. METHODS: Quadratic phase is imparted to the image to spread the signals in k-space (aka phase scrambling). By rewriting the Fourier transform as a convolution operation, a window can be introduced to the convolved chirp function, allowing a low-resolution image to be reconstructed from phase-scrambled data without prominent aliasing. This image (for each RF channel) can be used to derive coil sensitivities to drive existing parallel imaging techniques. As a proof of concept, the quadratic phase was applied by introducing an offset to the x(2) - y(2) shim and the data were reconstructed using adapted versions of the image space-based sensitivity encoding and GeneRalized Autocalibrating Partially Parallel Acquisitions algorithms. RESULTS: The method is demonstrated in a phantom (1 × 2, 1 × 3, and 2 × 2 acceleration) and in vivo (2 × 2 acceleration) using a 3D gradient echo acquisition. CONCLUSION: Phase scrambling can be used to perform parallel imaging acceleration without acquisition of separate coil calibration data, demonstrated here for a 3D-Cartesian trajectory. Further research is required to prove the applicability to other 2D and 3D sampling schemes. Magn Reson Med, 2014. © 2014 Wiley Periodicals, Inc.
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Mineral dust aerosols recently collected at the high-altitude Jungfraujoch research station (46 degrees 33'51 `' N, 7 degrees 59'06 `' E; 3580 m a.s.l.) were compared to mineral dust deposited at the Colle Gnifetti glacier (45 degrees 52'50 `' N, 7 degrees 52'33 `' E; 4455 m a.s.l.) over the last millennium. Radiogenic isotope signatures and backward trajectories analyses indicate that major dust sources are situated in the north-central to north-western part of the Saharan desert. Less radiogenic Sr isotopic compositions of PM10 aerosols and of mineral particles deposited during periods of low dust transfer likely result from the enhancement of the background chemically-weathered Saharan source. Saharan dust mobilization and transport were relatively reduced during the second part of the Little Ice Age (ca. 1690-1870) except within the greatest Saharan dust event deposited around 1770. After ca. 1870, sustained dust deposition suggests that increased mineral dust transport over the Alps during the last century could be due to stronger spring/summer North Atlantic southwesterlies and drier winters in North Africa. On the other hand, increasing carbonaceous particle emissions from fossil fuel combustion combined to a higher lead enrichment factor point to concomitant anthropogenic sources of particulate pollutants reaching high-altitude European glaciers during the last century.
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Previous electrophysiological studies revealed that human faces elicit an early visual event-related potential (ERP) within the occipito-temporal cortex, the N170 component. Although face perception has been proposed to rely on automatic processing, the impact of selective attention on N170 remains controversial both in young and elderly individuals. Using early visual ERP and alpha power analysis, we assessed the influence of aging on selective attention to faces during delayed-recognition tasks for face and letter stimuli, examining 36 elderly and 20 young adults with preserved cognition. Face recognition performance worsened with age. Aging induced a latency delay of the N1 component for faces and letters, as well as of the face N170 component. Contrasting with letters, ignored faces elicited larger N1 and N170 components than attended faces in both age groups. This counterintuitive attention effect on face processing persisted when scenes replaced letters. In contrast with young, elderly subjects failed to suppress irrelevant letters when attending faces. Whereas attended stimuli induced a parietal alpha band desynchronization within 300-1000 ms post-stimulus with bilateral-to-right distribution for faces and left lateralization for letters, ignored and passively viewed stimuli elicited a central alpha synchronization larger on the right hemisphere. Aging delayed the latency of this alpha synchronization for both face and letter stimuli, and reduced its amplitude for ignored letters. These results suggest that due to their social relevance, human faces may cause paradoxical attention effects on early visual ERP components, but they still undergo classical top-down control as a function of endogenous selective attention. Aging does not affect the face bottom-up alerting mechanism but reduces the top-down suppression of distracting letters, possibly impinging upon face recognition, and more generally delays the top-down suppression of task-irrelevant information.
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AIM: To describe the incidence of retinocytomas, their variability at presentation and their growth patterns both before and after regression.¦METHODS: Medical notes of the 525 patients of the Jules-Gonin Eye Hospital Retinoblastoma Clinic between 1964 and 2008 were reviewed and the charts of 36 patients with retinocytomas and/or phthisis bulbi were selected.¦RESULTS: The proportion of patients with retinocytomas and/or phthisis bulbi was 3.2%. The mean age at diagnosis was 28.7±17 years. Five tumours presented a cystic pattern (5.8%). Evidence of aggressive exophytic disease prior to spontaneous regression was documented in two eyes, and of invasive endophytic disease (regressed vitreous seeding or internal limiting membrane disruption) in three eyes. Twenty patients were followed with a mean follow-up of 44±60 months. Tumour growth was observed in 16% cases, benign cystic enlargement in 4% and malignant transformation in 12%.¦CONCLUSION: This large study of retinocytomas substantially expands the published features of retinocytoma by describing the cystic nature of some retinocytomas as well as clinical characteristics of the endophytic and exophytic preregression growth patterns. The authors report two different patterns of reactivation: benign cystic enlargement and malignant transformation with or without cystic growth. Higher than previously reported frequency of growth and possible life-threatening complications impose close lifetime follow-up of retinocytoma patients.
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The use of self-calibrating techniques in parallel magnetic resonance imaging eliminates the need for coil sensitivity calibration scans and avoids potential mismatches between calibration scans and subsequent accelerated acquisitions (e.g., as a result of patient motion). Most examples of self-calibrating Cartesian parallel imaging techniques have required the use of modified k-space trajectories that are densely sampled at the center and more sparsely sampled in the periphery. However, spiral and radial trajectories offer inherent self-calibrating characteristics because of their densely sampled center. At no additional cost in acquisition time and with no modification in scanning protocols, in vivo coil sensitivity maps may be extracted from the densely sampled central region of k-space. This work demonstrates the feasibility of self-calibrated spiral and radial parallel imaging using a previously described iterative non-Cartesian sensitivity encoding algorithm.
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The Committee of the European Concerted Action for Multiple Sclerosis (Charcot Foundation) organised five workshops to discuss CSF analytical standards in the diagnosis of multiple sclerosis. This consensus report from 12 European countries summarises the results of those workshops. It is hoped that neurologists will confer with their colleagues in clinical chemistry to arrange the best possible local practice. The most sensitive method for the detection of oligoclonal immunoglobulin bands is isoelectric focusing. The same amounts of IgG in parallel CSF and serum samples are used and oligoclonal bands are revealed with IgG specific antibody staining. All laboratories performing isoelectric focusing should check their technique at least annually using "blind" standards for the five different CSF and serum patterns. Quantitative measurements of IgG production in the CNS are less sensitive than isoelectric focusing. The preferred method for detection of blood-CSF barrier dysfunction is the albumin quotient. The CSF albumin or total protein concentrations are less satisfactory. These results must be interpreted with reference to the age of the patient and the local method of determination. Cells should be counted. The normal value is no more than 4 cells/microliters. Among evolving optional tests, measurement of the combined local synthesis of antibodies against measles, rubella, and/or varicella zoster could represent a significant advance if it offers higher specificity (not sensitivity) for identifying chronic rather than acute inflammation. Other tests that may have useful correlations with clinical indices include those for oligoclonal free light chains, IgM, IgA, or myelin basic protein concentrations.
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Calceology is the study of recovered archaeological leather footwear and is comprised of conservation, documentation and identification of leather shoe components and shoe styles. Recovered leather shoes are complex artefacts that present technical, stylistic and personal information about the culture and people that used them. The current method in calceological research for typology and chronology is by comparison with parallel examples, though its use poses problems by an absence of basic definitions and the lack of a taxonomic hierarchy. The research findings of the primary cutting patterns, used for making all leather footwear, are integrated with the named style method and the Goubitz notation, resulting in a combined methodology as a basis for typological organisation for recovered footwear and a chronology for named shoe styles. The history of calceological research is examined in chapter two and is accompanied by a review of methodological problems as seen in the literature. Through the examination of various documentation and research techniques used during the history of calceological studies, the reasons why a standard typology and methodology failed to develop are investigated. The variety and continual invention of a new research method for each publication of a recovered leather assemblage hindered the development of a single standard methodology. Chapter three covers the initial research with the database through which the primary cutting patterns were identified and the named styles were defined. The chronological span of each named style was established through iterative cross-site sedation and named style comparisons. The technical interpretation of the primary cutting patterns' consistent use is due to constraints imposed by the leather and the forms needed to cover the foot. Basic parts of the shoe patterns and the foot are defined, plus terms provided for identifying the key points for pattern making. Chapter four presents the seventeen primary cutting patterns and their sub-types, these are divided into three main groups: six integral soled patterns, four hybrid soled patterns and seven separately soled patterns. Descriptions of the letter codes, pattern layout, construction principle, closing seam placement and list of sub-types are included in the descriptions of each primary cutting pattern. The named shoe styles and their relative chronology are presented in chapter five. Nomenclature for the named styles is based on the find location of the first published example plus the primary cutting pattern code letter. The named styles are presented in chronological order from Prehistory through to the late 16th century. Short descriptions of the named styles are given and illustrated with examples of recovered archaeological leather footwear, reconstructions of archaeological shoes and iconographical sources. Chapter six presents documentation of recovered archaeological leather using the Goubitz notation, an inventory and description of style elements and fastening methods used for defining named shoe styles, technical information about sole/upper constructions and the consequences created by the use of lasts and sewing forms for style identification and fastening placement in relation to the instep point. The chapter concludes with further technical information about the implications for researchers about shoemaking, pattern making and reconstructive archaeology. The conclusion restates the original research question of why a group of primary cutting patterns appear to have been used consistently throughout the European archaeological record. The quantitative and qualitative results from the database show the use of these patterns but it is the properties of the leather that imposes the use of the primary cutting patterns. The combined methodology of primary pattern identification, named style and artefact registration provides a framework for calceological research.
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Variation in protein sequence and gene expression each contribute to phenotypic diversity, and may be subject to similar selective pressures. Eusocial insects are particularly useful for investigating the evolutionary link between protein sequence and condition-dependent patterns of gene expression because gene expression plays a central role in determining differences between eusocial insect sexes and castes. We investigated the relationship between protein coding sequence evolution and gene expression patterns in the fire ants Solenopsis invicta, S. richteri, and their hybrids to gain greater insight into how selection jointly operates on gene expression and coding sequence. We found that genes with high expression variability within castes and sexes were frequently differentially expressed between castes and sexes, as well as between species and hybrids. These results indicate that genes showing high variation in expression in one context also tend to show high variation in expression in other contexts. Our analyses further revealed that variation in both intra- and interspecific gene expression was positively associated with rate of protein sequence evolution in Solenopsis. This suggests that selective constraints on a gene operate both at the level of protein sequence and at the level of gene expression regulation. Overall, our study provides one of the strongest demonstrations that selective constraints mediate both protein sequence evolution and gene expression variability across different biological contexts and timescales.