961 resultados para pre-competitive anxiety


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Pcf11p, an essential subunit of the yeast cleavage factor IA, is required for pre‐mRNA 3′ end processing, binds to the C‐terminal domain (CTD) of the largest subunit of RNA polymerase II (RNAP II) and is involved in transcription termination. We show that the conserved CTD interaction domain (CID) of Pcf11p is essential for cell viability. Interestingly, the CTD binding and 3′ end processing activities of Pcf11p can be functionally uncoupled from each other and provided by distinct Pcf11p fragments in trans. Impaired CTD binding did not affect the 3′ end processing activity of Pcf11p and a deficiency of Pcf11p in 3′ end processing did not prevent CTD binding. Transcriptional run‐on analysis with the CYC1 gene revealed that loss of cleavage activity did not correlate with a defect in transcription termination, whereas loss of CTD binding did. We conclude that Pcf11p is a bifunctional protein and that transcript cleavage is not an obligatory step prior to RNAP II termination.

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A Monte Carlo model of an Elekta iViewGT amorphous silicon electronic portal imaging device (a-Si EPID) has been validated for pre-treatment verification of clinical IMRT treatment plans. The simulations involved the use of the BEAMnrc and DOSXYZnrc Monte Carlo codes to predict the response of the iViewGT a-Si EPID model. The predicted EPID images were compared to the measured images obtained from the experiment. The measured EPID images were obtained by delivering a photon beam from an Elekta Synergy linac to the Elekta iViewGT a-Si EPID. The a-Si EPID was used with no additional build-up material. Frame averaged EPID images were acquired and processed using in-house software. The agreement between the predicted and measured images was analyzed using the gamma analysis technique with acceptance criteria of 3% / 3 mm. The results show that the predicted EPID images for four clinical IMRT treatment plans have a good agreement with the measured EPID signal. Three prostate IMRT plans were found to have an average gamma pass rate of more than 95.0 % and a spinal IMRT plan has the average gamma pass rate of 94.3 %. During the period of performing this work a routine MLC calibration was performed and one of the IMRT treatments re-measured with the EPID. A change in the gamma pass rate for one field was observed. This was the motivation for a series of experiments to investigate the sensitivity of the method by introducing delivery errors, MLC position and dosimetric overshoot, into the simulated EPID images. The method was found to be sensitive to 1 mm leaf position errors and 10% overshoot errors.

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ABSTRACT A rapidly changing business environment and legacy IT problems has resulted in many organisations implementing standard package solutions. This 'common systems' approach establishes a common IT and business process infrastructure within organisations and its increasing dominance raises several important strategic issues. These are to what extent do common systems impose common business processes and management systems on competing firms, and what is the source of competitive advantage if the majority of firms employ almost identical information systems and business processes? A theoretical framework based on research into legacy systems and earlier IT strategy literature is used to analyse three case studies in the manufacturing, chemical and IT industries. It is shown that the organisations are treating common systems as the core of their organisations' abilities to manage business transactions. To achieve competitive advantage they are clothing these common systems with information systems designed to capture information about competitors, customers and suppliers, and to provide a basis for sharing knowledge within the organisation and ultimately with economic partners. The importance of these approaches to other organisations and industries is analysed and an attempt is made at outlining the strategic options open to firms beyond the implementation of common business systems.

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While past knowledge-based approaches to service innovation have emphasized the role of knowledge integration in the delivery of customer-focused solutions, these approaches do not adequately address the complexities inherent in knowledge acquisition and integration in project-oriented firms. Adopting a dynamic capability framework and building on knowledge-based approaches to innovation, the current study examines how the interplay of learning capabilities and knowledge integration capability impacts service innovation and sustained competitive advantage. This two-stage multi-sample study finds that entrepreneurial project-oriented service firms in their quest for competitive advantage through greater innovation invest in knowledge acquisition and integration capabilities. Implications for theory and practice are discussed and directions for future research provided.

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The extensive use of alkoxyamines in controlled radical polymerisation and polymer stabilisation is based on rapid cycling between the alkoxyamine (R1R2NO–R3) and a stable nitroxyl radical (R1R2NO•) via homolysis of the labile O–C bond. Competing homolysis of the alkoxyamine N–O bond has been predicted to occur for some substituents leading to production of aminyl and alkoxyl radicals. This intrinsic competition between the O–C and N–O bond homolysis processes has to this point been difficult to probe experimentally. Herein we examine the effect of local molecular structure on the competition between N–O and O–C bond cleavage in the gas phase by variable energy tandem mass spectrometry in a triple quadrupole mass spectrometer. A suite of cyclic alkoxyamines with remote carboxylic acid moieties (HOOC–R1R2NO–R3) were synthesised and subjected to negative ion electrospray ionisation to yield [M – H]− anions where the charge is remote from the alkoxyamine moiety. Collision-induced dissociation of these anions yield product ions resulting, almost exclusively, from homolysis of O–C and/or N–O bonds. The relative efficacy of N–O and O–C bond homolysis was examined for alkoxyamines incorporating different R3 substituents by varying the potential difference applied to the collision cell, and comparing dissociation thresholds of each product ion channel. For most R3 substituents, product ions from homolysis of the O–C bond are observed and product ions resulting from cleavage of the N–O bond are minor or absent. A limited number of examples were encountered however, where N–O homolysis is a competitive dissociation pathway because the O–C bond is stabilised by adjacent heteroatom(s) (e.g., R3 = CH2F). The dissociation threshold energies were compared for different alkoxyamine substituents (R3) and the relative ordering of these experimentally determined energies is shown to correlate with the bond dissociation free energies, calculated by ab initio methods. Understanding the structure-dependent relationship between these rival processes will assist in the design and selection of alkoxyamine motifs that selectively promote the desirable O–C homolysis pathway.

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OBJECTIVE To evaluate changes in outdoor workers' sun-related attitudes, beliefs, and behaviors in response to a health promotion intervention using a participatory action research process. METHODS Fourteen workplaces across four outdoor industry types worked collaboratively with the project team to develop tailored sun protection action plans. Workers were assessed before and after the 18-month intervention. RESULTS Outdoor workers reported increases in workplace support for sun protection (P < 0.01) and personal use of sun protection (P < 0.01). More workers reported seeking natural shade (+20%) and wearing more personal protective equipment, including broad-brimmed hats (+25%), long-sleeved collared shirts (+19%), and long trousers (+16%). The proportion of workers reporting sunburn over the past 12 months was lower at postintervention (-14%) (P = 0.03); however, the intensity of reported sunburn increased. CONCLUSIONS This intervention was successful in increasing workers' sun protective attitudes, beliefs, and behaviors.

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We characterised the effects of selective oestrogen receptor modulators (SERM) in explant cultures of human endometrium tissue. Endometrium tissues were cultured for 24 h in Millicell-CM culture inserts in serum-free medium in the presence of vehicle,17 beta-estradiol (17 beta-E2,1 nM), oestrogen receptor (ER) antagonist ICI 164.384 (40 nM), and 4-OH-tamoxifen (40 nM), raloxifene (4 nM), lasofoxifene (4 nM)and acolbifene (4 nM). Protein expression of ER alpha, ER beta 1 and Ki-67 were evaluated by immunohistochemistry (IHC). The proliferative fraction was assessed by counting the number of Ki-67 positive cells. Nuclear staining of ER( and ER(1 was observed in the glandular epithelium and stroma of pre- and postmenopausal endometrium. ER(1 protein was also localized in the endothelial cells of blood vessels. Treating premenopausal endometrium tissue with 17 beta-E2 increased the fraction of Ki-67 positive cells (p < 0.001) by 55% in glands compared to the control. Raloxifene (4 nM) increased (p < 0.05) the Ki-67 positive fraction. All other SERMS did not affect proliferation in this model. Treating postmenopausal endometrium with 17(-E2 increased (p < 0.001) the fraction of Ki-67 positive cells by 250% in glands compared to the control. A similar effect was also seen for 4-OH-tamoxifen, whereas the rest of SERMs did not stimulate proliferation. We demonstrated that oestradiol increases the fraction of proliferating cells in short term explant cultures of postmenopausal endometrium. In addition, we were able to reveal the agonistic properties of 4-OH-tamoxifen and confirm that raloxifene and next-generation SERMs acolbifene and lasofoxifene were neutral on the human postmenopausal endometrium. (C) 2008 Elsevier Ltd. All rights reserved.

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Background Supine imaging modalities provide valuable 3D information on scoliotic anatomy, but the altered spine geometry between the supine and standing positions affects the Cobb angle measurement. Previous studies report a mean 7°-10° Cobb angle increase from supine to standing, but none have reported the effect of endplate pre-selection or whether other parameters affect this Cobb angle difference. Methods Cobb angles from existing coronal radiographs were compared to those on existing low-dose CT scans taken within three months of the reference radiograph for a group of females with adolescent idiopathic scoliosis. Reformatted coronal CT images were used to measure supine Cobb angles with and without endplate pre-selection (end-plates selected from the radiographs) by two observers on three separate occasions. Inter and intra-observer measurement variability were assessed. Multi-linear regression was used to investigate whether there was a relationship between supine to standing Cobb angle change and eight variables: patient age, mass, standing Cobb angle, Risser sign, ligament laxity, Lenke type, fulcrum flexibility and time delay between radiograph and CT scan. Results Fifty-two patients with right thoracic Lenke Type 1 curves and mean age 14.6 years (SD 1.8) were included. The mean Cobb angle on standing radiographs was 51.9° (SD 6.7). The mean Cobb angle on supine CT images without pre-selection of endplates was 41.1° (SD 6.4). The mean Cobb angle on supine CT images with endplate pre-selection was 40.5° (SD 6.6). Pre-selecting vertebral endplates increased the mean Cobb change by 0.6° (SD 2.3, range −9° to 6°). When free to do so, observers chose different levels for the end vertebrae in 39% of cases. Multi-linear regression revealed a statistically significant relationship between supine to standing Cobb change and fulcrum flexibility (p = 0.001), age (p = 0.027) and standing Cobb angle (p < 0.001). The 95% confidence intervals for intra-observer and inter-observer measurement variability were 3.1° and 3.6°, respectively. Conclusions Pre-selecting vertebral endplates causes minor changes to the mean supine to standing Cobb change. There is a statistically significant relationship between supine to standing Cobb change and fulcrum flexibility such that this difference can be considered a potential alternative measure of spinal flexibility.

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Background: Seizures and interictal spikes in mesial temporal lobe epilepsy (MTLE) affect a network of brain regions rather than a single epileptic focus. Simultaneous electroencephalography and functional magnetic resonance imaging (EEG-fMRI) studies have demonstrated a functional network in which hemodynamic changes are time-locked to spikes. However, whether this reflects the propagation of neuronal activity from a focus, or conversely the activation of a network linked to spike generation remains unknown. The functional connectivity (FC) changes prior to spikes may provide information about the connectivity changes that lead to the generation of spikes. We used EEG-fMRI to investigate FC changes immediately prior to the appearance of interictal spikes on EEG in patients with MTLE. Methods/principal findings: Fifteen patients with MTLE underwent continuous EEG-fMRI during rest. Spikes were identified on EEG and three 10 s epochs were defined relative to spike onset: spike (0–10 s), pre-spike (−10 to 0 s), and rest (−20 to −10 s, with no previous spikes in the preceding 45s). Significant spike-related activation in the hippocampus ipsilateral to the seizure focus was found compared to the pre-spike and rest epochs. The peak voxel within the hippocampus ipsilateral to the seizure focus was used as a seed region for FC analysis in the three conditions. A significant change in FC patterns was observed before the appearance of electrographic spikes. Specifically, there was significant loss of coherence between both hippocampi during the pre-spike period compared to spike and rest states. Conclusion/significance: In keeping with previous findings of abnormal inter-hemispheric hippocampal connectivity in MTLE, our findings specifically link reduced connectivity to the period immediately before spikes. This brief decoupling is consistent with a deficit in mutual (inter-hemispheric) hippocampal inhibition that may predispose to spike generation.

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This research was embedded as a Design-led Innovation catalyst within a family-owned small business, to explore the application of a design program to achieve organizational change. Based on the findings two new models for increasing design integration within an organisation were proposed, establishing a range of pre-requisites needed for a firm to progress. Struggling firms may leverage their use of design and strategy by embedding a catalyst in a new cross-disciplinary role providing the necessary internal assistance. The study demonstrated that even non-design or strategy-inclined family-owned SMEs could benefit from embarking on a design-led journey to boost their competitive preparedness.

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In male tephritid fruit flies of the genus Bactrocera, feeding on secondary plant compounds (sensu lato male lures = methyl eugenol, raspberry ketone and zingerone) increases male mating success. Ingested male lures alter the male pheromonal blend, normally making it more attractive to females and this is considered the primary mechanism for the enhanced mating success. However, the male lures raspberry ketone and zingerone are known, across a diverse range of other organisms, to be involved in increasing energy metabolism. If this also occurs in Bactrocera, then this may represent an additional benefit to males as courtship is metabolically expensive and lure feeding may increase a fly's short-term energy. We tested this hypothesis by performing comparative RNA-seq analysis between zingerone-fed and unfed males of Bactrocera tryoni. We also carried out behavioural assays with zingerone- and cuelure-fed males to test whether they became more active. RNA-seq analysis revealed, in zingerone-fed flies, up-regulation of 3183 genes with homologues transcripts to those known to regulate intermale aggression, pheromone synthesis, mating and accessory gland proteins, along with significant enrichment of several energy metabolic pathways and gene ontology terms. Behavioural assays show significant increases in locomotor activity, weight reduction and successful mating after mounting; all direct/indirect measures of increased activity. These results suggest that feeding on lures leads to complex physiological changes, which result in more competitive males. These results do not negate the pheromone effect, but do strongly suggest that the phytochemical-induced sexual selection is governed by both female preference and male competitive mechanisms.