989 resultados para 146-890


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An exact theoretical solution is given for the stresses and displacements in an infinite plate of finite thickness having a circular hole and subjected to axisymmetric normal leading. The solution is given in the form of Fourier-Bessel series and integral. Numerical results are given for stresses in plates having different thickness to hole diameter ratios and loadings. The results are compared with the available approximate theoretical and experimental results.

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Abstract. We have used chlortetracycline (CTC) as a fluorescent probe to detect the distribution of sequestered calcium in multicellular stages of Dictyostelium discoideum. Tips of late aggregates, slugs and early culminating masses fluoresce very strongly. Most of the fluorescence is intracellular in origin and emanates from a small number of intense punctate sources. The sources correspond in part to autophagic vacuoles viz. neutral-red staining, acidic digestive vesicles, and may also include intracellular organelles; cytoplasmic fluorescence is much weaker in comparison. The level of fluorescence drops in the middle portion of slugs and rises again in the posteriormost region, though not to as high a level as in the tip. This holds good irrespective of whether CTC is applied only in the neighbourhood of the aggregate centre, only in the aggregate periphery, or to the whole aggregate. We infer that there must be a good deal of mixing in the stages leading from aggregation to slug formation; thus the serial order in which cells enter an aggregate does not bear any relation to their ultimate fates. The other implication of our study is that calcium sequestration is much more extensive in prestalk and anterior-like cells than in prespore cells. These findings are discussed with regard to possible implications for pattern formation.

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Background Poor clinical handover has been associated with inaccurate clinical assessment and diagnosis, delays in diagnosis and test ordering, medication errors and decreased patient satisfaction in the acute care setting. Research on the handover process in the residential aged care sector is very limited. Purpose The aims of this study were to: (i) Develop an in-depth understanding of the handover process in aged care by mapping all the key activities and their information dynamics, (ii) Identify gaps in information exchange in the handover process and analyze implications for resident safety, (iii) Develop practical recommendations on how information communication technology (ICT) can improve the process and resident safety. Methods The study was undertaken at a large metropolitan facility in NSW with more than 300 residents and a staff including 55 registered nurses (RNs) and 146 assistants in nursing (AINs). A total of 3 focus groups, 12 interviews and 3 observation sessions were conducted over a period from July to October 2010. Process mapping was undertaken by translating the qualitative data via a five-category code book that was developed prior to the analysis. Results Three major sub-processes were identified and mapped. The three major stages are Handover process (HOP) I “Information gathering by RN”, HOP II “Preparation of preliminary handover sheet” and HOP III “Execution of handover meeting”. Inefficient processes were identified in relation to the handover including duplication of information, utilization of multiple communication modes and information sources, and lack of standardization. Conclusion By providing a robust process model of handover this study has made two critical contributions to research in aged care: (i) a means to identify important, possibly suboptimal practices; and (ii) valuable evidence to plan and improve ICT implementation in residential aged care. The mapping of this process enabled analysis of gaps in information flow and potential impacts on resident safety. In addition it offers the basis for further studies into a process that, despite its importance for securing resident safety and continuity of care, lacks research.

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We conducted two studies to improve our understanding of why and when older workers are focused on learning. Based on socioemotional selectivity theory, which proposes that goal focus changes with age and the perception of time, we hypothesized and found that older workers perceive their remaining time at work as more limited than younger workers which, in turn, is associated with lower learning goal orientation and a less positive attitude toward learning and development. Furthermore, we hypothesized and found that high work centrality buffers the negative association between age and perceived remaining time, and thus the indirect negative effects of age on learning goal orientation and attitude toward learning and development (through perceived remaining time). These findings suggest that scholars and practitioners should take workers’ perceived remaining time and work centrality into account when examining or stimulating learning activities among aging workers.

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The unsteady laminar incompressible boundary-layer flow near the three-dimensional asymmetric stagnation point has been studied under the assumptions that the free-stream velocity, wall temperature, and surface mass transfer vary arbitrarily with time. The partial differential equations governing the flow have been solved numerically using an implicit finite-difference scheme. It is found that in contrast with the symmetric flow, the maximum heat transfer occurs away from the stagnation point due to the decrease in the boundary-layer thickness. The effect of the variation of the wall temperature with time on heat transfer is strong. The skin friction and heat transfer due to asymmetric flow only are comparatively less affected by the mass transfer as compared to those of symmetric flow.

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O6-Alkylguanine-DNA alkyltransferase (AGT) repairs O6-methylguanine (O6mG) in DNA that is known to cause Mutation and cancer. On the basis of Calculations performed using density functional theory involving the active site of AGT, a mechanism for catalytic demethylation of O6mG to guanine has been proposed. In this mechanism, roles of six amino acids, i.e., Cys145, His 146, Glu172, Tyr114, Lys165, and Ser159 in catalytic demethylation of O6mG are involved. This mechanism has three steps as follows. At the first step, Cys145 in the Cys145-water-His146-Glu172 tetrad is converted to cysteine thiolate anion while at the second step, abstraction of the Tyr114 proton by the N3 site of O6mG occurs in a barrierless manner. In the third step, abstraction of Lys165 proton by deprotonated Tyr114 and transfer of the methyl group of O6mG to the thiolate group of Cys145 anion Occur simultaneously. As AGT is a major target in cancer therapy, identification of the roles of the different amino acids in demethylation of O6mG is expected to be useful in designing efficient AGT inhibitors.

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Breast cancer is the most common form of potentially fatal cancer in women in the Western world. Better understanding of the breast cancer disease process together with developments in treatments have led to improved survival and reduced risk of recurrence, significantly influencing the acceptance of breast reconstructions as part of breast cancer treatment. Skin-sparing mastectomy followed by immediate breast reconstruction has proved superior to other forms of breast reconstruction in terms of aesthetic outcome. However, due to the relatively recent introduction of skin-sparing mastectomy concerns on the surgical and oncological safety of the operation persist. The aim of the present study is to evaluate the surgical and oncological safety of skin-sparing mastectomy and immediate breast reconstruction in a consecutive patient series with ensuing follow-up. Subsequent aims of the study are to examine possibilities of reducing surgical complications of the operation and to assess the feasibility of sentinel node biopsy together with immediate breast reconstruction. The study population comprises a consecutive series of patients having undergone skin-sparing mastectomy followed by immediate breast reconstruction at the Helsinki University Central Hospital between 1992 and 2006. In Study I, the hospital records of 207 patients, operated between 1992 and 2001, were analyzed for surgical complications and recurrences of breast cancer during follow-up. In Study II, 60 consecutive patients were randomized into either conventional diathermy or radiofrequency coagulation groups to examine possibilities of reducing skin-flap complications. Study III consists of 62 consecutive breast cancer patients evaluated for the feasibility of sentinel node biopsy simultaneously with immediate breast reconstruction. In Study IV, hospital records were analyzed to examine local recurrence of breast cancer in a consecutive series of 146 patients with Stage I or II disease. Post-operative complications in Study I included native skin-flap necrosis (10.1%), hematoma (10.1%), anastomose thrombosis (5.3%), infection (3.4%), hernia (2.6%) and loss of one microvascular flap (0.7%). The Stage I and II patients in Study IV had a local recurrence rate of 2.7%, an isolated regional lymph node recurrence rate of 2.1% and a systemic recurrence rate of 2.7%, during a mean follow-up time of 51 months. The Stage III patients in study I had a locoregional recurrence rate of 31.3% during follow-up. Radiofrequency coagulation in Study II did not decrease skin-flap complications when compared with conventional diathermy. An increased skin-flap complication rate in Study II was associated with smoking and the type of skin incision used. In Study III, eleven patients had tumor positive sentinel nodes, nine of which were detected intraoperatively. Skin-sparing mastectomy followed by immediate breast reconstruction is a safe procedure both surgically and oncologically, especially for early stage breast cancer. Tennis racket type incision is associated with an increased skin-flap complication rate. Sentinel node biopsy with intraoperative assessment of sentinel node metastases is feasible in patients undergoing immediate breast reconstruction.

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Common migraine, i.e. migraine with (MA) or without aura (MO), is a chronic neurological disorder affecting about 10% of the Caucasian population. In MA, migraine headache is preceded by visual, sensoric and/or dysphasic reversible aura symptoms. Twin and family studies have suggested a multifactorial mode of inheritance for common migraine, and a stronger genetic component for MA than for MO. Since there is no biological or genetic marker to identify common migraine, aura symptoms provide a distinctive character to identify those suspected of suffering from migraine. The aim of this study was to identify MA susceptibility loci in well-phenotyped migraine samples with familial predisposition using different gene mapping methods. Genes coding for endothelin1 and its receptors EDNRA and ENDRB are potential candidate genes for cortical spreading depression (CSD), which is considered to be the underlying mechanism of migraine aura. The role of these genes in MA was studied in 850 Finnish migraine cases and 890 control individuals. Rare homozygous EDNRA SNPs showed nominal association with MA and with the age of onset trait (20 years). This result was also detected in the pooled analysis on 648 German MA cases and 651 control individuals when the test was adjusted for gender and sample origin. Evaluation of SNP genotyping reactions with two different DNA polymerase enzymes ensured that the genotype quality was high, and thus the discovered associations are considered reliable. The role of the 19p13 region was studied in a linkage analysis of 72 Finnish MA families. This region contains two migraine-associated genes: CACNA1A, which is associated with a predisposition to a rare Mendelian form of MA, familial hemiplegic migraine (FHM), and the insulin receptor gene (INSR) that is associated with common migraine. No evidence of linkage between the 19p13 and MA was detected. A novel visual aura locus was mapped to chromosome 9q21-q22 with significant evidence of linkage using a genome-wide linkage approach in 36 Finnish MA families. Five additional, potential loci were also detected. The 9q21-q22 region has previously been linked to occipitotemporal lobe epilepsy and MA, both of which involve prominent visual symptoms. Our result further supports a shared background for these episodic disorders.

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Samanaikainen alkoholiriippuvuus ja vakava masennustila on haasteellista sekä lääketieteelliselle hoidolle että tutkimukselle. Tämä oireyhtymä on yksi yleisimmistä psykiatrisista häiriöistä niin Yhdysvalloissa kuin Suomessakin. Potilaiden ja heidän omaistensa inhimillisen kärsimyksen lisäksi myös kokonaistaloudelliset terveydenhoidolliset kustannukset ovat suuret tämän oireyhtymän hoidossa: niiden arvioidaan olevan yli neljäkymmentä prosenttia korkeammat kuin pelkän depression kohdalla. Tässä tutkimuksessa pyrittiin löytämään uusia hoidollisia vaihtoehtoja alkoholiriippuvuudesta ja vakavasta masennuksesta yhtäaikaisesti kärsivien potilaiden hoidossa. Tutkimukseen osallistui 80 potilasta Helsingin kaupungin kolmelta A-klinikalta. Kyseessä oli kaksoissokko, randomisoitu, kahden eri tavalla vaikuttavan lääkkeen, essitalopraamin (selektiivinen serotoniinin takaisinoton estäjä) ja memantiinin (glutamaatin NMDA reseptorin ei-kilpaileva estäjä) vertaileva tutkimus. Potilaiden oireiden kulkua seurattiin 26 viikkoa depressioon, ahdistuneisuuteen, kogniitioihin, elämänlaatuun ja alkoholin käyttöön liittyvillä mittareilla. Tämän jälkeen tarkasteltiin hoitovastetta alkutilanne- ja taustamuuttujien valossa. Pyrkimyksenä oli löytää joitakin ennustekijöitä, joiden pohjalta kliinikko voisi tehdä hoitoratkaisunsa näiden potilaiden hoidossa. Molemmat lääkkeet vähensivät merkittävästi sekä masennusta että ahdistuneisuutta, eikä essitalopraami- ja memantiiniryhmien välillä ollut tilastollisesti merkitsevää eroa. Kognitiiviset toiminnot olivat lähtövaiheessa normatiivisella tasolla. Elämän laatu parani molemmissa hoitoryhmissä. Alkoholimittareilla AUDIT (alkoholihäiriöiden tunnistusmittari) ja OCDS (pakkomielteisen ja pakkotoimintoisen alkoholinkäytön mittari) paranivat molemmissa hoitoryhmissä. Varhainen ensimmäisen vakavan masennuksen episodin alku näytti ennakoivan huonoa vastetta essitalopraamille, mutta ei memantiinille, mitattuna Montgomery-Åsberg depression rating scale -asteikolla. Toisaalta myöhäinen ensimmäisen masennuksen episodi näytti ennakoivan hyvää hoitovastetta essitalopraamille. Niinpä ensimmäisen masennuksen alkamisikä saattaisi olla käyttökelpoinen ennustekijä näille lääkkeille. Varhainen humalahakuisen juomisen alkamisikä näytti ennustavan huonoa hoitovastetta molemmille lääkkeille, erityisesti essitalopraamille, mitattuna AUDIT-mittarilla. Aktiivinen alkoholinkäyttö tutkimuksen alkaessa ennakoi tutkimuksen keskeyttämistä. HTTLPR-geenin L-alleeli näytti ennustavan parempaa hoitovastetta essitalopraamille masennukseen kuin S-alleeli.

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Enantioselective syntheses of both cis, syn, cis- and cis, anti, cis-linear triquinanes, starting from the readily available (S)-campholenaldehyde, employing an RCM reaction-based cyclopentannulation strategy, are described.

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The hot deformation behaviour of Mg–3Al alloy has been studied using the processing-map technique. Compression tests were conducted in the temperature range 250–550 °C and strain rate range 3 × 10−4 to 102 s−1 and the flow stress data obtained from the tests were used to develop the processing map. The various domains in the map corresponding to different dissipative characteristics have been identified as follows: (i) grain boundary sliding (GBS) domain accommodated by slip controlled by grain boundary diffusion at slow strain-rates (<10−3 s−1) in the temperature range from 350 to 450 °C, (ii) two different dynamic recrystallization (DRX) domains with a peak efficiency of 42% at 550 °C/10−1 s−1 and 425 °C/102 s−1 governed by stress-assisted cross-slip and thermally activated climb as the respective rate controlling mechanisms and (iii) dynamic recovery (DRV) domain below 300 °C in the intermediate strain rate range from 3 × 10−2 to 3 × 10−1 s−1. The regimes of flow instability have also been delineated in the processing map using an instability criterion. Adiabatic shear banding at higher strain rates (>101 s−1) and solute drag by substitutional Al atoms at intermediate strain rates (3 × 10−2 to 3 × 10−1 s−1) in the temperature range (350–450 °C) are responsible for flow instability. The relevance of these mechanisms with reference to hot working practice of the material has been indicated. The processing maps of Mg–3Al alloy and as-cast Mg have been compared qualitatively to elucidate the effect of alloying with aluminum on the deformation behaviour of magnesium.

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Background: The irreversible epidermal growth factor receptor (EGFR) inhibitors have demonstrated efficacy in NSCLC patients with activating EGFR mutations, but it is unknown if they are superior to the reversible inhibitors. Dacomitinib is an oral, small-molecule irreversible inhibitor of all enzymatically active HER family tyrosine kinases. Methods: The ARCHER 1009 (NCT01360554) and A7471028 (NCT00769067) studies randomized patients with locally advanced/metastatic NSCLC following progression with one or two prior chemotherapy regimens to dacomitinib or erlotinib. EGFR mutation testing was performed centrally on archived tumor samples. We pooled patients with exon 19 deletion and L858R EGFR mutations from both studies to compare the efficacy of dacomitinib to erlotinib. Results: One hundred twenty-one patients with any EGFR mutation were enrolled; 101 had activating mutations in exon 19 or 21. For patients with exon19/21 mutations, the median progression-free survival was 14.6 months [95% confidence interval (CI) 9.0–18.2] with dacomitinib and 9.6 months (95% CI 7.4–12.7) with erlotinib [unstratified hazard ratio (HR) 0.717 (95% CI 0.458–1.124), two-sided log-rank, P = 0.146]. The median survival was 26.6 months (95% CI 21.6–41.5) with dacomitinib versus 23.2 months (95% CI 16.0–31.8) with erlotinib [unstratified HR 0.737 (95% CI 0.431–1.259), two-sided log-rank, P = 0.265]. Dacomitinib was associated with a higher incidence of diarrhea and mucositis in both studies compared with erlotinib. Conclusions: Dacomitinib is an active agent with comparable efficacy to erlotinib in the EGFR mutated patients. The subgroup with exon 19 deletion had favorable outcomes with dacomitinib. An ongoing phase III study will compare dacomitinib to gefitinib in first-line therapy of patients with NSCLC harboring common activating EGFR mutations (ARCHER 1050; NCT01774721). Clinical trials number: ARCHER 1009 (NCT01360554) and A7471028 (NCT00769067).

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The purpose of this study is to investigate the accounting choice decisions of banks to employ Level 3 inputs in estimating the value of their financial assets and liabilities. Using a sample of 146 bank-year observations from 18 countries over 2009-2012, this study finds banks’ incentives to use Level 3 valuation inputs are associated with both firm-level and country-level determinants. At the firm-level, leverage, profitability (in term of net income), Tier 1 capital ratio, size and audit committee independence are associated with the percentage of Level 3 valuation inputs. At the country-level, economy development, legal region, legal enforcement and investor rights are also associated with the Level 3 classification choice. Lastly, ‘secrecy’, the proxy for culture dimensions and values, is found to be positively associated with the use of Level 3 valuation inputs. Altogether, these findings suggest that banks use the discretion available under Level 3 inputs opportunistically to avoid violating debt covenants limits, to increase earnings and manage their capital ratios. Results of this study also highlight that corporate governance quality at the firm-level (e.g. audit committee independence) and institutional features can constrain banks’ opportunistic behaviors in using the discretion available under Level 3 inputs. The results of this study have important implications for standard setters and contribute to the debate on the use of fair value accounting in an international context.

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The purpose of this study is to investigate the accounting choice decisions of banks to employ Level 3 inputs in estimating the value of their financial assets and liabilities. Using a sample of 146 bank-year observations from 18 countries over 2009-2012, this study finds banks’ incentives to use Level 3 valuation inputs are associated with both firm-level and country-level determinants. At the firm-level, leverage, profitability (in term of net income), Tier 1 capital ratio, size and audit committee independence are associated with the percentage of Level 3 valuation inputs. At the country-level, economy development, legal region, legal enforcement and investor rights are also associated with the Level 3 classification choice. Lastly, ‘secrecy’, the proxy for culture dimensions and values, is found to be positively associated with the use of Level 3 valuation inputs. Altogether, these findings suggest that banks use the discretion available under Level 3 inputs opportunistically to avoid violating debt covenants limits, to increase earnings and manage their capital ratios. Results of this study also highlight that corporate governance quality at the firm-level (e.g. audit committee independence) and institutional features can constrain banks’ opportunistic behaviors in using the discretion available under Level 3 inputs. The results of this study have important implications for standard setters and contribute to the debate on the use of fair value accounting in an international context.

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The basic lectin from winged bean (Psophocarpus tetragonolobus) could be crystallized using polyethyleneglycol (PEG) 4000 (I), PEG 8000 (II) and 2-methylpentane-2,4-diol (MPD) (III) as precipitants. Crystal forms I and II grew in the presence of methyl-α-Image -galactopyranoside or N -acetylgalactosamine while III grew in the absence of sugar. The three forms have the same space group (P21212) and similar unit cell dimensions with two dimeric molecules in the asymmetric unit. The unit cell dimensions are a = 156·8 Å, b = 89·0 Å, c = 73·3 Å for I, a = 155·5 Å, b = 92·3 Å, c = 72·5 Å for II and a = 148·3 Å, b = 90·7 Å, c = 73·8 Å for III. The crystals, particularly those grown using PEG 8000, are suitable for high resolution X-ray analysis, which is in progress.