590 research outputs found
Late Cretaceous and Paleogene radiolaria from the Nicoya Peninsula, Costa Rica: A tectonostratigraphic application
Detailed field mapping and paleontological dating in the central and southeastern Nicoya Peninsula has revealed Late Cretaceous and Paleogene radiolarian-bearing siliceous mudstones. These rocks belong to two terranes (Matambú and Manzanillo) that are partially contemporaneous with the Nicoya Complex, but are genetically different. While the Nicoya Complex is formed exclusively by intraplate igneous rocks with associated radiolarites, the studied sections include variable amounts of arc-derived volcanic and terrigenous materials. These fore-arc terranes include mafic to intermediate volcaniclastics and associated pelagic and hemipelagic rocks rich in biogenic silica. Radiolarian preservation in these sediments is often enhanced by the presence of silica-saturated volcanic tuffs and debris. Seven out of 29 samples from different outcrops yielded relatively well-preserved radiolarian faunas. In total, 60 species belonging to 34 genera were present in these faunas, ranging in age from middle Turonian-Santonian to late Thanetian-Ypresian
Kinase activator protein mediates longer-term effects of starvation on activity of pyruvate dehydrogenase kinase in rat liver mitochondria
Creating university spin-offs: A science-based design perspective
Academic entrepreneurship by means of university spin-offs commercializes technological breakthroughs, which may otherwise remain unexploited. However, many universities face difficulties in creating spin-offs. This article adopts a science-based design approach to connect scholarly research with the pragmatics of effectively creating university spin-offs. This approach serves to link the practice of university spin-off creation, via design principles, to the scholarly knowledge in this area. As such, science-based design promotes the interplay between emergent and deliberate design processes. This framework is used to develop a set of design principles that are practice based as well as grounded in the existing body of research on university spin-offs. A case-study of spin-off creation at a Dutch university illustrates the interplay between initial processes characterized by emergent design and the subsequent process that was more deliberate in nature. This case study also suggests there are two fundamentally different phases in building capacity for university spin-off creation. First, an infrastructure for spin-off creation (including a collaborative network of investors, managers and advisors) is developed that then enables support activities to individual spin-off ventures. This study concludes that to build and increase capacity for creating spin-offs, universities should do the following: (1) create university-wide awareness of entrepreneurship opportunities, stimulate the development of entrepreneurial ideas, and subsequently screen entrepreneurs and ideas by programs targeted at students and academic staff; (2) support start-up teams in composing and learning the right mix of venturing skills and knowledge by providing access to advice, coaching, and training; (3) help starters in obtaining access to resources and developing their social capital by creating a collaborative network organization of investors, managers, and advisors; (4) set clear and supportive rules and procedures that regulate the university spin-off process, enhance fair treatment of involved parties, and separate spin-off processes from academic research and teaching; and (5) shape a university culture that reinforces academic entrepreneurship by creating norms and exemplars that motivate entrepreneurial behavior. These and other results of this study illustrate how science-based design can connect scholarly research to the pragmatics of actually creating spin-offs in academic institutions
More than sense of place? Exploring the emotional dimension of rural tourism experiences
It is widely suggested that participation in rural tourism is underpinned by a sense of rural place or “rurality”. However, although nature and the countryside have long been recognised as a source of spiritual or emotional fulfilment, few have explored the extent to which tourism, itself often claimed to be a sacred experience, offers an emotional/spiritual dimension in the rural context. This paper addresses that literature gap. Using in-depth interviews with rural tourists in the English Lake District, it explores the extent to which, within respondents’ individual understanding of spirituality, a relationship exists between sense of place and deeper, emotional experiences and, especially, whether participation in rural tourism may induce spiritual or emotional responses. The research revealed that all respondents felt a strong attachment to the Lake District; similarly, and irrespective of their openness to spirituality, engaging in rural tourism activities resulted in highly emotive experiences for all respondents, the description/interpretation of such experiences being determined by individual “beliefs”. However, sense of place was not a prerequisite to emotional or spiritual experiences. Being in and engaging with the landscape � effectively becoming part of it � especially through physical activity is fundamental to emotional responses
Leptin Matures Aspects of Lung Structure and Function in the Ovine Fetus
In human and ovine fetuses, glucocorticoids stimulate leptin secretion, although the extent to which leptin mediates the maturational effects of glucocorticoids on pulmonary development is unclear. This study investigated the effects of leptin administration on indices of lung structure and function before birth. Chronically catheterized singleton sheep fetuses were infused iv for 5 days with either saline or recombinant ovine leptin (0.5 mg/kg · d leptin (LEP), 0.5 LEP or 1.0 mg/kg · d, 1.0 LEP) from 125 days of gestation (term ∼145 d). Over the infusion, leptin administration increased plasma leptin, but not cortisol, concentrations. On the fifth day of infusion, 0.5 LEP reduced alveolar wall thickness and increased the volume at closing pressure of the pressure-volume deflation curve, interalveolar septal elastin content, secondary septal crest density, and the mRNA abundance of the leptin receptor (Ob-R) and surfactant protein (SP) B. Neither treatment influenced static lung compliance, maximal lung volume at 40 cmH2O, lung compartment volumes, alveolar surface area, pulmonary glycogen, protein content of the long form signaling Ob-Rb or phosphorylated signal transducers and activators of transcription-3, or mRNA levels of SP-A, C, or D, elastin, vascular endothelial growth factor-A, the vascular endothelial growth factor receptor 2, angiotensin-converting enzyme, peroxisome proliferator-activated receptor γ, or parathyroid hormone-related peptide. Leptin administration in the ovine fetus during late gestation promotes aspects of lung maturation, including up-regulation of SP-B
Pyruvate dehydrogenase-complex activity in brown adipose tissue of gold thioglucose-obese mice
Inactivation of pyruvate dehydrogenase complex in heart muscle mitochondria of gold-thioglucose-induced obese mice is not due to a stable increase in activity of pyruvate dehydrogenase kinase
Tectono-stratigraphic response of the Sandino Forearc Basin (N-Costa Rica and W-Nicaragua) to episodes of rough crust and oblique subduction
The southern Central American active margin is a world-class site where past and
present subduction processes have been extensively studied. Tectonic erosion/accretion
and oblique/orthogonal subduction are thought to alternate in space and time
along the Middle American Trench. These processes may cause various responses
in the upper plate, such as uplift/subsidence, deformation, and volcanic arc migration/
shut-off. We present an updated stratigraphic framework of the Late Cretaceous–
Cenozoic Sandino Forearc Basin (SFB) which provides evidence of
sedimentary response to tectonic events. Since its inception, the basin was predominantly
filled with deep-water volcaniclastic deposits. In contrast, shallow-water
deposits appeared episodically in the basin record and are considered as tectonic
event markers. The SFB stretches for about 300 km and varies in thickness from
5 km (southern part) to about 16 km (northern part). The drastic, along-basin, thickness
variation appears to be the result of (1) differential tectonic evolutions and (2)
differential rates of sediment supply. (1) The northern SFB did not experience major
tectonic events. In contrast, the reduced thickness of the southern SFB (5 km) is the
result of at least four uplift phases related to the collision/accretion of bathymetric
reliefs on the incoming plate: (i) the accretion of a buoyant oceanic plateau (Nicoya
Complex) during the middle Campanian; (ii) the collision of an oceanic plateau (?)
during the late Danian–Selandian; (iii) the collision/accretion of seamounts during
the late Eocene–early Oligocene; (iv) the collision of seamounts and ridges during
the Pliocene–Holocene. (2) The northwestward thickening of the SFB may have
been enhanced by high sediment supply in the Fonseca Gulf area which reflects
sourcing from wide, high relief drainage basins. In contrast, sedimentary input has
possibly been lower along the southern SFB, due to the proximity of the narrow,
lowland isthmus of southern Central America. Moreover, two phases of strongly
oblique subduction affected the margin, producing strike-slip faulting in the forearc
basin: (1) prior to the Farallon Plate breakup, an Oligocene transpressional phase
caused deformation and uplift of the basin depocenter, triggering shallowing-upward
of the Nicaraguan Isthmus in the central and northern SFB; (2) a Pleistocene–Holocene transtensional phase drives the NW-directed motion of a forearc sliver
and reactivation of the graben-bounding faults of the late Neogene Nicaraguan
Depression. We discuss arguments in favour of a Pliocene development of the
Nicaraguan Depression and propose that the Nicaraguan Isthmus, which is the
apparent rift shoulder of the depression, represents a structure inherited from the Oligocene
transpressional phase
Towards a methodology for cluster searching to provide conceptual and contextual "richness" for systematic reviews of complex interventions: case study (CLUSTER)
Background
Systematic review methodologies can be harnessed to help researchers to understand and explain how complex interventions may work. Typically, when reviewing complex interventions, a review team will seek to understand the theories that underpin an intervention and the specific context for that intervention. A single published report from a research project does not typically contain this required level of detail. A review team may find it more useful to examine a “study cluster”; a group of related papers that explore and explain various features of a single project and thus supply necessary detail relating to theory and/or context.
We sought to conduct a preliminary investigation, from a single case study review, of techniques required to identify a cluster of related research reports, to document the yield from such methods, and to outline a systematic methodology for cluster searching.
Methods
In a systematic review of community engagement we identified a relevant project – the Gay Men’s Task Force. From a single “key pearl citation” we conducted a series of related searches to find contextually or theoretically proximate documents. We followed up Citations, traced Lead authors, identified Unpublished materials, searched Google Scholar, tracked Theories, undertook ancestry searching for Early examples and followed up Related projects (embodied in the CLUSTER mnemonic).
Results
Our structured, formalised procedure for cluster searching identified useful reports that are not typically identified from topic-based searches on bibliographic databases. Items previously rejected by an initial sift were subsequently found to inform our understanding of underpinning theory (for example Diffusion of Innovations Theory), context or both. Relevant material included book chapters, a Web-based process evaluation, and peer reviewed reports of projects sharing a common ancestry. We used these reports to understand the context for the intervention and to explore explanations for its relative lack of success. Additional data helped us to challenge simplistic assumptions on the homogeneity of the target population.
Conclusions
A single case study suggests the potential utility of cluster searching, particularly for reviews that depend on an understanding of context, e.g. realist synthesis. The methodology is transparent, explicit and reproducible. There is no reason to believe that cluster searching is not generalizable to other review topics. Further research should examine the contribution of the methodology beyond improved yield, to the final synthesis and interpretation, possibly by utilizing qualitative sensitivity analysis
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