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Conrad Deep: a new northern Red Sea deep. Origin and implications for continental rifting
A previously unknown deep, here called Conrad Deep, was discovered during an extensive geophysical survey of the northern Red Sea in June, 1984. Conrad Deep is located at 27°03’N, 34°43’E, only 90 km south of the Gulf of Suez and is the most northern deep yet discovered in the Red Sea. It is located within a well developed axial depression which also contains Charcot Deep, 100 km to the south. The axial depression is associated with abundant recent deformation and is situated at the peak of a regional heat flow high extending across the rift. Conrad Deep is typical of the small northern type Red Sea Deep. It is 10 km long, 2 km wide and has a maximum depth of 1460 m. It is associated with high and variable heat flow values and large magnetic anomalies. There is no evidence of a dense brine layer. Detailed analysis of the geophysical data implies that the deep probably results from a very recent (< 40,000 years) intrusion into continental type basement. The formation of a well defined axial depression associated with very high heat flow and small deeps resulting from isolated intrusions may be the first step in the transition from continental extension to seafloor spreading
Shear wave splitting in southern tyrrhenian subduction zone (Italy) from CESIS and CAT/SCAN projects
In the years 2003 -2006 several broad band stations were installed in Southern Italy:
15 permanent ones (CESIS project), improved the INGV Italian national network and 40 temporary ones were installed in the frame of CAT/SCAN NSF project.We present shear wave splitting measurements obtained analyzing SKS phases and local S phases
from slab earthquakes. We used the method of Silver & Chan to obtain shear wave splitting parameters: fast direction and delay time. Shear wave splitting measurements reveals strong seismic anisotropy in the mantle beneath Southern Tyrrhenian subduction
system. The SKS splitting results show fast polarization directions varying from NNW-SSE in the Southern Apennines to N-S and to E-SW in Calabria, following the strike of the mountain chain. Moving toward the Adriatic sea the fast directions rotate from N-S to NE-SW. Fast directions could indicate the mantle flow below the slab, due to its retrograde motion but also the lithospheric fabric of the subducting plate. In the Tyrrhenian domain, above the slab, from Sardinia to the Italian and Sicilian
coasts the dominant fast direction is E-W and could be related to the opening of the Tyrrhenian basin and to the corner flow in the asthenospheric wedge. In Sicily fast directions depict a ring around the slab edge supporting the existence of a slab
tear and of a return flow from the back to the front of the slab. Measurements obtained
with intermediate and deep earthquakes slab S phases show an extremely complex pattern of fast directions. They are mostly distributed in front of the Tyrrhenian Calabrian coast in correspondence of the fast velocity anomaly imaged at 150 km depth
by tomography. We can relate this fast directions variability to the complex structure of the slab itself. The complex pattern of SKS and S splitting measurements suggests the presence of local scale mantle flow controled by the motion of an anisotropic slab
SKS splittings in the southern Apennines-Calabrian arc region (southern Italy)
During the years 2003-2006 CAT/SCAN (Calbarian-Apennine-TyrrhenianlSubductionCollision-
Accretion Network) temporary broadband stations operate in Southern Apennine
and Calabria (Italy). In the same period CESIS-INGV project improved the number of
permanent seismic stations in the same area. We analyze the data recorded to study seismic
anisotropy and to investigate the mantle flow in the boun(fary-zoile{ between Southern
Apennine and Calabriaibeneath and above the subducting slab. In the current work we
present new shear wave splittings obtained analyzing SKS phases of 15 teleseisms with
epicentral distance ranging from 88.40 to 98.20 and magnitude greater than 6.0. We used the method of Silver & Chan (1991) to obtained anisotropic parameters: delay time and fast polarization direction. The splitting parameters reveal strong seismic anisotropy in the mantle beneath Southern Tyrrhenian Sea- Calabrian Arc System that seems to be controlled by the slab presence. The clear variability in the fast directions allow us to hypothesize the existence of different anisotropic domains: fast polarization directions vary from NNW -SSE
in the tyrrhenian side ofthe Southern Apennine to N-S and NE-SW toward the Adriatic Sea. Moving toward the Calabria fast directions are prevalently trench parallel showing a NE-SW orientation following the strike on the mountain chain
Crustal Structure in the Southern Apennines from Teleseismic Receiver Functions
While the upper structure of the Southern Apennines is known, lack of control on the deep structure allows competing thin-skin and tick-skin models of the orogen. In thin-skin models the detachment decouples a stack of rootless nappes from the basement. In the tick-skin models, besement is involved in the most recent phase of thrusting. To examine crustal structure, we use teleseismic data from the CAT/SCAN array in southern Italy. We use receiver functions (RF) processed into a Common Conversion Point (CCP) stack to generate images of the crust. Interpretation and correlation to geological structure is done using inversions of individual station RFs. We focus on a shallow discontinuity where P-to-S conversions occur. In the foreland, it corresponds to velocity jumps between carbonate and clastic strata with basement. A similar interpretation for the Apennines provides the most parsimonious explanation and supports a tick-skin interpretation. In a thick-skin reconstruction, the amount of shortening is much smaller than for a thin-skin model. This implies considerably less Plio-Pleistocene shortening across the Apennines and suggests an E-SE motion of the Calabrian Arc subparallel to the southern Apennines rather than a radial expansion of the Arc
Strategies to Promote Physical Activity During Pregnancy
Physical activity during pregnancy has been associated with significant health benefits; however, most women in the United States do not meet the current guidelines. This systematic review evaluates evidence for interventions to improve physical activity during pregnancy in order to identify best practices and inform future research. Electronic databases (PubMed, CINAHL, SportDISCUS, Embase, ERIC, Psych Info, and ISI Web of Science) were searched in July 2011 for peer-reviewed journal articles. Studies were included if they were English-language randomized control trials that measured the efficacy of an intervention targeted at pregnant women and were designed to change physical activity as a primary or secondary outcome. Out of 777 studies identified through the systematic search, 9 interventions were selected for inclusion by multiple reviewers. Data were abstracted using an abstraction form modeled after the "Guide to Community Preventive Services." Of the 9 interventions included in the review, 3 reported statistically significant positive results for physical activity. Although the interventions included a variety of strategies and techniques, none were uniquely associated with positive outcomes. Overall, this review suggests that little is known about the efficacy of interventions for physical activity during pregnancy. This study provides several recommendations for future research and intervention design
Illumination of the Crustal Structure in the Southern Apennines using Teleseismic Receiver Functions, CAT/SCAN Project
Field geology, well data and seismic imaging have illuminated the upper crustal structure of the Southern Apennines. However, lack of control of the deep structure allows viable competing thin-skin and thick-skin models of the orogen. In thin-skin models the detachment decouples a stack of rootless nappes from the basement. In thick-skin models, basement is involved in the most recent phase of thrusting. To examine the deep crustal structure, we use the teleseismic recordings from the CAT/SCAN array, deployed in southern Italy from Dec. 2003-Oct. 2005. We use receiver functions processed into a Common Conversion Point stack to generate images of the crust. We image three main westward-dipping seismic-velocity discontinuities where P-to-S conversions occur. They correspond to velocity jumps at the Moho, the upper-lower crust boundary and sedimentary interfaces resulting from the contrast between clastic and carbonate strata with basement. The CCP image matches features from both thin-skin and thick skin model. The lateral continuity of the converters favors thin skin, but consistent interpretation across the image favors the thick skin. Overall, the results provide a better fit to the thick-skin interpretation. This suggests a change in structural style as the collision with Apulia halted motion. This model also implies considerably less Plio-Pleistocene shortening across the Apennines and a SE motion of the Calabrian Arc subparallel to the southern Apennines rather than a radial expansion of the Arc
Internet-based psychoeducation for bipolar disorder: a qualitative analysis of feasibility, acceptability and impact
<p>Background: In a recent exploratory randomised trial we found that a novel, internet-based psychoeducation programme for bipolar disorder (Beating Bipolar) was relatively easy to deliver and had a modest effect on psychological quality of life. We sought to explore the experiences of participants with respect to feasibility, acceptability and impact of Beating Bipolar.</p>
<p>Methods: Participants were invited to take part in a semi-structured interview. Thematic analysis techniques were employed; to explore and describe participants’ experiences, the data were analysed for emerging themes which were identified and coded.</p>
<p>Results: The programme was feasible to deliver and acceptable to participants where they felt comfortable using a computer. It was found to impact upon insight into illness, health behaviour, personal routines and positive attitudes towards medication. Many participants regarded the programme as likely to be most beneficial for those recently diagnosed.</p>
<p>Conclusions: An online psychoeducation package for bipolar disorder, such as Beating Bipolar, is feasible and acceptable to patients, has a positive impact on self-management behaviours and may be particularly suited to early intervention. Alternative (non-internet) formats should also be made available to patients.</p>
Process evaluation results from a school- and community-linked intervention: the Trial of Activity for Adolescent Girls (TAAG)
Process evaluation is a component of intervention research that evaluates whether interventions are delivered and received as intended. Here, we describe the process evaluation results for the Trial of Activity for Adolescent Girls (TAAG) intervention. The intervention consisted of four synergistic components designed to provide supportive school- and community-linked environments to prevent the decline in physical activity in adolescent girls. Process evaluation results indicate that the intervention components were delivered from intervention staff to teachers with high fidelity (84–97%) to the protocol and with lower fidelity (range: 18–93%) from teachers to students. Physical activity programs for girls, a unique feature of the TAAG intervention, increased from a mean of 10 programs per school to a mean of 16 and 15 in years 1 and 2, respectively, in intervention schools, with no change in control schools. These findings suggest that a multicomponent school- and community-based physical activity intervention can be delivered with fidelity and result in a middle school environment that supports physical activity for girls
“Having all of your internal resources exhausted beyond measure and being left with no clean-up crew”: defining autistic burnout
Background: Although autistic adults often discuss experiencing ‘‘autistic burnout’’ and attribute serious negative outcomes to it, the concept is almost completely absent from the academic and clinical literature.
Methods: We used a community-based participatory research approach to conduct a thematic analysis of 19 interviews and 19 public Internet sources to understand and characterize autistic burnout. Interview participants were autistic adults who identified as having been professionally diagnosed with an autism spectrum condition. We conducted a thematic analysis, using a hybrid inductive–deductive approach, at semantic and latent levels, through a critical paradigm. We addressed trustworthiness through multiple coders, peer debriefing, and examination of contradictions.
Results: Autistic adults described the primary characteristics of autistic burnout as chronic exhaustion, loss of skills, and reduced tolerance to stimulus. They described burnout as happening because of life stressors that added to the cumulative load they experienced, and barriers to support that created an inability to obtain relief from the load. These pressures caused expectations to outweigh abilities resulting in autistic burnout. Autistic adults described negative impacts on their health, capacity for independent living, and quality of life, including suicidal behavior. They also discussed a lack of empathy from neurotypical people and described acceptance and social support, time off/reduced expectations, and doing things in an autistic way/unmasking as associated in their experiences with recovery from autistic burnout.
Conclusions: Autistic burnout appears to be a phenomenon distinct from occupational burnout or clinical depression. Better understanding autistic burnout could lead to ways to recognize, relieve, or prevent it, including highlighting the potential dangers of teaching autistic people to mask or camouflage their autistic traits, and including burnout education in suicide prevention programs. These findings highlight the need to reduce discrimination and stigma related to autism and disability
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