3,289 research outputs found
Why grit requires perseverance and passion to positively predict performance
This is the final version. Available from the publisher via the DOI in this record.Data deposition: Data and scripts related to this paper are available at https://osf.io/
kp7cb/Prior studies linking gritâdefined as perseverance and passion for
long-term goalsâto performance are beset by contradictory evidence. As a result, commentators have increasingly declared that grit
has limited effects. We propose that this inconsistent evidence has
occurred because prior research has emphasized perseverance and
ignored, both theoretically and empirically, the critical role of passion,
which we define as a strong feeling toward a personally important
value/preference that motivates intentions and behaviors to express
that value/preference. We suggest that combining the grit scaleâ
which only captures perseveranceâwith a measure that assesses
whether individuals attain desired levels of passion will predict performance. We first metaanalyzed 127 studies (n = 45,485) that used
the grit scale and assessed performance, and found that effect sizes
are larger in studies where participants were more passionate for the
performance domain. Second, in a survey of employees matched to
supervisor-rated job performance (n = 422), we found that the combination of perseverance, measured through the grit scale, and passion attainment, measured through a new scale, predicted higher
performance. A final study measured perseverance and passion attainment in a sample of students (n = 248) and linked these to their
grade-point average (GPA), finding that the combination of perseverance and passion attainment predicted higher GPAs in part through
increased immersion. The present results help resolve the mixed evidence of gritâs relationship with performance by highlighting the
important role that passion plays in predicting performance. By adequately measuring both perseverance and passion, the present research uncovers gritâs true predictive power
Regulation of pancreatic cancer aggressiveness by stromal stiffening
No abstract available
Contact Manifolds, Contact Instantons, and Twistor Geometry
Recently, Kallen and Zabzine computed the partition function of a twisted
supersymmetric Yang-Mills theory on the five-dimensional sphere using
localisation techniques. Key to their construction is a five-dimensional
generalisation of the instanton equation to which they refer as the contact
instanton equation. Subject of this article is the twistor construction of this
equation when formulated on K-contact manifolds and the discussion of its
integrability properties. We also present certain extensions to higher
dimensions and supersymmetric generalisations.Comment: v3: 28 pages, clarifications and references added, version to appear
in JHE
The concept of remembrance in Walter Benjamin
This thesis argues that the role played by the concept of remembrance (Eingedenken)
in Walter Benjamin's 'theory of the knowledge of history' and in his engagement with
Enlightenment universal history, is a crucial one. The implications of Benjamin's
contention that history's 'original vocation' is 'remembrance' have hitherto gone
largely unnoticed. The following thesis explores the meaning of the concept of
remembrance and assesses the significance of this proposed link between history and
memory, looking at both the mnemonic aspect of history and the historical facets of
memory. It argues that by mobilising the simultaneously destructive and constructive
capacities of remembrance, Benjamin sought to develop a critical historiography
which would enable a radical encounter with a previously suppressed past. In so doing
he takes up a stance (explicit and implicit) towards existing philosophical conceptions
of history, in particular the idea of universal history found in German Idealism.
Benjamin reveals an intention to retain the epistemological aspirations of universal
history whilst ridding that approach of its apologetic moment. He criticises existing
conceptions of history on the basis that each assumes homogeneous time to be the
framework in which historical events occur. Insight into the distinctive temporality of
remembrance proves to be the touchstone for this critique, and provides a paradigm
for a very different conception of time. The thesis goes on to determine what is valid
and what is problematic both in this concept of remembrance and in the theory of
historical knowledge which it informs, by subjecting both to the most cogent
criticisms which can be levelled at them. What emerges is not only the importance of
this concept for an understanding of Benjamin's philosophy but the pertinence of this
concept for any philosophical account of memory
Search for electric dipole moments at storage rings
Permanent electric dipole moments (EDMs) violate parity and time reversal
symmetry. Within the Standard Model (SM) they are many orders of magnitude
below present experimental sensitivity. Many extensions of the SM predict much
larger EDMs, which are therefore an excellent probe for the existence of "new
physics". Until recently it was believed that only electrically neutral systems
could be used for sensitive searches of EDMs. With the introduction of a novel
experimental method, high precision for charged systems will be within reach as
well. The features of this method and its possibilities are discussed.Comment: Proc. EXA2011, 6 pages;
http://www.springerlink.com/content/45l35376832vhrg0
A thin layer angiogenesis assay: a modified basement matrix assay for assessment of endothelial cell differentiation
BACKGROUND: Basement matrices such as Matrigel⢠and Geltrex⢠are used in a variety of cell culture assays of anchorage-dependent differentiation including endothelial cell tube formation assays. The volumes of matrix recommended for these assays (approximately 150 Οl/cm(2)) are costly, limit working distances for microscopy, and require cell detachment for subsequent molecular analysis. Here we describe the development and validation of a thin-layer angiogenesis (TLA) assay for assessing the angiogenic potential of endothelial cells that overcomes these limitations. RESULTS: Geltrex⢠basement matrix at 5 Οl/cm(2) in 24-well (10 Οl) or 96-well (2 Οl) plates supports endothelial cell differentiation into tube-like structures in a comparable manner to the standard larger volumes of matrix. Since working distances are reduced, high-resolution single cell microscopy, including DIC and confocal imaging, can be used readily. Using MitoTracker dye we now demonstrate, for the first time, live mitochondrial dynamics and visualise the 3-dimensional network of mitochondria present in differentiated endothelial cells. Using a standard commercial total RNA extraction kit (Qiagen) we also show direct RNA extraction and RT-qPCR from differentiated endothelial cells without the need to initially detach cells from their supporting matrix. CONCLUSIONS: We present here a new thin-layer assay (TLA) for measuring the anchorage-dependent differentiation of endothelial cells into tube-like structures which retains all the characteristics of the traditional approach but with the added benefit of a greatly lowered cost and better compatibility with other techniques, including RT-qPCR and high-resolution microscopy. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1186/s12860-014-0041-5) contains supplementary material, which is available to authorized users
Metaâanalysis of fenestrated endovascular aneurysm repair versus open surgical repair of juxtarenal abdominal aortic aneurysms over the last 10âyears
Background
Juxtarenal abdominal aortic aneurysms pose a significant challenge whether managed endovascularly or by open surgery. Fenestrated endovascular aneurysm repair (FEVAR) is now well established, but few studies have compared it with open surgical repair (OSR). The aim of this systematic review was to compare shortâ and longâterm outcomes of FEVAR and OSR for the management of juxtarenal aortic aneurysms.
Methods
A literature search was conducted of the Ovid Medline, EMBASE and PubMed databases. Reasons for exclusion were series with fewer than 20 patients, studies published before 2007 and those concerning ruptured aneurysms. Owing to variance in definitions, the terms âjuxta/para/suprarenalâ were used; thoracoabdominal aortic aneurysms were excluded. Primary outcomes were 30âday/inâhospital mortality and renal insufficiency. Secondary outcomes included major complication rates, rate of reintervention and rates of endoleak.
Results
Twentyâseven studies were identified, involving 2974 patients. Study designs included 11 case series, 14 series within retrospective cohort studies, one caseâcontrol study and a single prospective nonârandomized trial. The pooled early postoperative mortality rate following FEVAR was 3¡3 (95 per cent c.i. 2¡0 to 5¡0) per cent, compared with 4¡2 (2¡9 to 5¡7) per cent after OSR. After FEVAR, the rate of postoperative renal insufficiency was 16¡2 (10¡4 to 23¡0) per cent, compared with 23¡8 (15¡2 to 33¡6) per cent after OSR. The major early complication rate following FEVAR was 23¡1 (16¡8 to 30¡1) per cent versus 43¡5 (34¡4 to 52¡8) per cent after OSR. The rate of late reintervention after FEVAR was higher than that after OSR: 11¡1 (6¡7 to 16¡4) versus 2¡0 (0¡6 to 4¡3) per cent respectively.
Conclusion
No significant difference was noted in 30âday mortality; however, FEVAR was associated with significantly lower morbidity than OSR. Longâterm durability is a concern, with far higher reintervention rates after FEVAR
- âŚ