182 research outputs found
Construction of next-generation superplastic forming using additive manufacturing and numerical techniques
The superplastic forming process is used in a wide range of high-value-added manufacturing sectors to make lightweight, complex-shaped components for high-performance applications. Currently, it is a high-cost process, for example, the superplastic forming of titanium alloys involves a high-temperature furnace, costly (mould) tooling and has a high utilization of resources such as argon gas and energy. The authors of this article propose a prototype for next-generation superplastic forming laboratory equipment. The aim is to develop improved methods, particularly for heat management in the superplastic forming process, to allow a more widespread application of the process to manufacture lower cost products. The next-generation superplastic forming tool comprises a tool in the form of a hemispherical shell, pressure chamber with incorporated water cooling system and an infrared heating system. The construction, usability and suitability of the next-generation superplastic forming equipment have been proven by a series of physical experiments, and numerical simulations are performed and the results are presented and discussed in this article
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Can information affect sensory perceptions? Evidence from a survey on Italian organic food consumers
This paper aims to investigate the influence of information on consumers’ preferences and sensory perceptions of organic food using a sample of 301 Italian organic food consumers. Consumers stated their preferences for “core organic” attributes, labels and information on food products and performed blind and informed tests on strawberry yoghurts and cookies. Data were analysed using descriptive analysis, Mann-Whitney U tests and Wilcoxon signed-rank test. Results revealed that consumers appreciate “core organic” attributes, like artisanal production and variability of sensory attributes. Comparing blind and informed tests, results showed that information affects the overall liking of products and consumers’ perception of product-specific sensory attributes. However, the influence of information on sensory perceptions depends on the product category, sensory attributes and the type of information provided
Population‐based cohort study of outcomes following cholecystectomy for benign gallbladder diseases
Background The aim was to describe the management of benign gallbladder disease and identify characteristics associated with all‐cause 30‐day readmissions and complications in a prospective population‐based cohort. Methods Data were collected on consecutive patients undergoing cholecystectomy in acute UK and Irish hospitals between 1 March and 1 May 2014. Potential explanatory variables influencing all‐cause 30‐day readmissions and complications were analysed by means of multilevel, multivariable logistic regression modelling using a two‐level hierarchical structure with patients (level 1) nested within hospitals (level 2). Results Data were collected on 8909 patients undergoing cholecystectomy from 167 hospitals. Some 1451 cholecystectomies (16·3 per cent) were performed as an emergency, 4165 (46·8 per cent) as elective operations, and 3293 patients (37·0 per cent) had had at least one previous emergency admission, but had surgery on a delayed basis. The readmission and complication rates at 30 days were 7·1 per cent (633 of 8909) and 10·8 per cent (962 of 8909) respectively. Both readmissions and complications were independently associated with increasing ASA fitness grade, duration of surgery, and increasing numbers of emergency admissions with gallbladder disease before cholecystectomy. No identifiable hospital characteristics were linked to readmissions and complications. Conclusion Readmissions and complications following cholecystectomy are common and associated with patient and disease characteristics
Oculomotor interference during manual response preparation: evidence from the response-cueing paradigm
Preparation provided by visual location cues is known to speed up behavior. However, the role of concurrent saccades in response to visual cues remains unclear. In this study, participants performed a spatial precueing task by pressing one of four response keys with one of four fingers (two of each hand) while eye movements were monitored. Prior to the stimulus, we presented a neutral cue (baseline), a hand cue (corresponding to left vs. right positions), or a finger cue (corresponding to inner vs. outer positions). Participants either remained fixated on a central fixation point or moved their eyes freely. The results demonstrated that saccades during the cueing interval altered the pattern of cueing effects. Finger cueing trials in which saccades were spatially incompatible (vs. compatible) with the subsequently required manual response exhibited slower manual RTs. We propose that interference between saccades and manual responses affects manual motor preparation
Nuclear localization and cytosolic overexpression of LASP-1 correlates with tumor size and nodal-positivity of human breast carcinoma
<p>Abstract</p> <p>Background</p> <p>LIM and SH3 protein 1 (LASP-1), initially identified from human breast cancer, is a specific focal adhesion protein involved in cell proliferation and migration, which was reported to be overexpressed in 8–12 % of human breast cancers and thought to be exclusively located in cytoplasm.</p> <p>Methods</p> <p>In the present work we analyzed the cellular and histological expression pattern of LASP-1 and its involvement in biological behavior of human breast cancer through correlation with standard clinicopathological parameters and expression of c-erbB2 (HER-2/neu), estrogen- (ER) and progesterone-receptors (PR). For this purpose immunohistochemical staining intensity and percentage of stained cells were semi-quantitatively rated to define a LASP-1 immunoreactive score (LASP-1-IRS). LASP-1-IRS was determined in 83 cases of invasive ductal breast carcinomas, 25 ductal carcinomas in situ (DCIS) and 18 fibroadenomas. Cellular LASP-1 distribution and expression pattern was visualized by immunofluorescence and confocal microscopy and assessed through separate Western blots of nuclear and cytosol preparations of BT-20, MCF-7, MDA-MB231, and ZR-75/1 breast cancer cells.</p> <p>Results</p> <p>Statistical analysis revealed that the resulting LASP-1-IRS was significantly higher in invasive carcinomas compared to fibroadenomas (p = 0.0176). Strong cytoplasmatic expression of LASP-1 was detected in 55.4 % of the invasive carcinomas, which correlated significantly with nuclear LASP-1-positivity (p = 0.0014), increased tumor size (p = 0.0159) and rate of nodal-positivity (p = 0.0066). However, levels of LASP-1 expression did not correlate with average age at time point of diagnosis, histological tumor grading, c-erbB2-, ER- or PR-expression.</p> <p>Increased nuclear localization and cytosolic expression of LASP-1 was found in breast cancer with higher tumor stage as well as in rapidly proliferating epidermal basal cells. Confocal microscopy and separate Western blots of cytosolic and nuclear preparations confirmed nuclear localization of LASP-1.</p> <p>Conclusion</p> <p>The current data provide evidence that LASP-1 is not exclusively a cytosolic protein, but is also detectable within the nucleus. Increased expression of LASP-1 in vivo is present in breast carcinomas with higher tumor stage and therefore may be related with worse prognosis concerning patients' overall survival.</p
LIM and SH3 Protein -1 Modulates CXCR2-Mediated Cell Migration
BACKGROUND: The chemokine receptor CXCR2 plays a pivotal role in migration of neutrophils, macrophages and endothelial cells, modulating several biological responses such as angiogenesis, wound healing and acute inflammation. CXCR2 is also involved in pathogenesis of chronic inflammation, sepsis and atherosclerosis. The ability of CXCR2 to associate with a variety of proteins dynamically is responsible for its effects on directed cell migration or chemotaxis. The dynamic network of such CXCR2 binding proteins is termed as "CXCR2 chemosynapse". Proteomic analysis of proteins that co-immunoprecipitated with CXCR2 in neutrophil-like dHL-60 cells revealed a novel protein, LIM and SH3 protein 1 (LASP-1), binds CXCR2 under both basal and ligand activated conditions. LASP-1 is an actin binding cytoskeletal protein, involved in the cell migration. METHODOLOGY/PRINCIPAL FINDINGS: We demonstrate that CXCR2 and LASP-1 co-immunoprecipitate and co-localize at the leading edge of migrating cells. The LIM domain of LASP-1 directly binds to the carboxy-terminal domain (CTD) of CXCR2. Moreover, LASP-1 also directly binds the CTD of CXCR1, CXCR3 and CXCR4. Using a site-directed and deletion mutagenesis approach, Iso323-Leu324 of the conserved LKIL motif on CXCR2-CTD was identified as the binding site for LASP-1. Interruption of the interaction between CXCR2-CTD and LIM domain of LASP-1 by dominant negative and knock down approaches inhibited CXCR2-mediated chemotaxis. Analysis for the mechanism for inhibition of CXCR2-mediated chemotaxis indicated that LASP-1/CXCR2 interaction is essential for cell motility and focal adhesion turnover involving activation of Src, paxillin, PAK1, p130CAS and ERK1/2. CONCLUSIONS/SIGNIFICANCE: We demonstrate here for the first time that LASP-1 is a key component of the "CXCR2 chemosynapse" and LASP-1 interaction with CXCR2 is critical for CXCR2-mediated chemotaxis. Furthermore, LASP-1 also directly binds the CTD of CXCR1, CXCR3 and CXCR4, suggesting that LASP-1 is a general mediator of CXC chemokine mediated chemotaxis. Thus, LASP-1 may serve as a new link coordinating the flow of information between chemokine receptors and nascent focal adhesions, especially at the leading edge. Thus the association between the chemokine receptors and LASP-1 suggests to the presence of a CXC chemokine receptor-LASP-1 pro-migratory module in cells governing the cell migration
Dynamism in the solar core
Recent results of a mixed shell model heated asymmetrically by transient
increases in nuclear burning indicate the transient generation of small hot
spots inside the Sun somewhere between 0.1 and 0.2 solar radii. These hot
bubbles are followed by a nonlinear differential equation system with finite
amplitude non-homologous perturbations which is solved in a solar model. Our
results show the possibility of a direct connection between the dynamic
phenomena of the solar core and the atmospheric activity. Namely, an initial
heating about DQ_0 ~ 10^{31}-10^{37} ergs can be enough for a bubble to reach
the outer convective zone. Our calculations show that a hot bubble can arrive
into subphotospheric regions with DQ_final ~ 10^{28} - 10^{34} ergs with a high
speed, up to 10 km s-1, approaching the local sound speed. We point out that
the developing sonic boom transforms the shock front into accelerated particle
beam injected upwards into the top of loop carried out by the hot bubble above
its forefront traveling from the solar interior. As a result, a new perspective
arises to explain flare energetics. We show that the particle beams generated
by energetic deep-origin hot bubbles in the subphotospheric layers have masses,
energies, and chemical compositions in the observed range of solar
chromospheric and coronal flares. It is shown how the emergence of a hot bubble
into subphotospheric regions offers a natural mechanism that can generate both
the eruption leading to the flare and the observed coronal magnetic topology
for reconnection. We show a list of long-standing problems of solar physics
that our model explains. We present some predictions for observations, some of
which are planned to be realized in the near future.Comment: 44 pages, 20 figure
Understanding Communication of Sustainability Reporting: Application of Symbolic Convergence Theory (SCT)
The purpose of this paper is to investigate the nature of rhetoric and rhetorical strategies that are implicit in the standalone sustainability reporting of the top 24 companies of the Fortune 500 Global. We adopt Bormann’s (Q J Speech 58(4):396–407, 1972) SCT framework to study the rhetorical situation and how corporate sustainability reporting (CSR) messages can be communicated to the audience (public). The SCT concepts in the sustainability reporting’s communication are subject to different types of legitimacy strategies that are used by corporations as a validity and legitimacy claim in the reports. A content analysis has been conducted and structural coding schemes have been developed based on the literature. The schemes are applied to the SCT model which recognizes the symbolic convergent processes of fantasy among communicators in a Society. The study reveals that most of the sample companies communicate fantasy type and rhetorical vision in their corporate sustainability reporting. However, the disclosure or messages are different across locations and other taxonomies of the SCT framework. This study contributes to the current CSR literature about how symbolic or fantasy understandings can be interpreted by the users. It also discusses the persuasion styles that are adopted by the companies for communication purposes. This study is the theoretical extension of the SCT. Researchers may be interested in further investigating other online communication paths, such as human rights reports and director’s reports
Overexpression of LASP-1 mediates migration and proliferation of human ovarian cancer cells and influences zyxin localisation
LIM and SH3 protein 1 (LASP-1), initially identified from human breast cancer, is a specific focal adhesion protein involved in cell proliferation and migration. In the present work, we analysed the effect of LASP-1 on biology and function of human ovarian cancer cell line SKOV-3 using small interfering RNA technique (siRNA).Transfection with LASP-1-specific siRNA resulted in a reduced protein level of LASP-1 in SKOV-3 cells. The siRNA-treated cells were arrested in G2/M phase of the cell cycle and proliferation of the tumour cells was suppressed by 60–90% corresponding to around 70% of the cells being transfected successfully as seen by immunofluorescence. Moreover, transfected tumour cells showed a 40% reduced migration. LASP-1 silencing is accompanied by a reduced binding of the LASP-1-binding partner zyxin to focal contacts without changes in actin stress fibre and microtubule organisation or focal adhesion morphology as observed by immunofluorescence. In contrast, silencing of zyxin is not influencing cell migration and had neither influence on LASP-1 expression nor actin cytoskeleton and focal contact morphology suggesting that LASP-1 is necessary and sufficient for recruiting zyxin to focal contacts.The data provide evidence for an essential role of LASP-1 in tumour cell growth and migration, possibly through influencing zyxin localization
QF2011: a protocol to study the effects of the Queensland flood on pregnant women, their pregnancies, and their children's early development
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