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Slow slip near the trench at the Hikurangi subduction zone, New Zealand
The range of fault slip behaviors near the trench at subduction plate boundaries is critical to know, as this is where the world’s largest, most damaging tsunamis are generated. Our knowledge of these behaviors has remained largely incomplete, partially due to the challenging nature of crustal deformation measurements at offshore plate boundaries. Here we present detailed seafloor deformation observations made during an offshore slow-slip event (SSE) in September and October 2014, using a network of absolute pressure gauges deployed at the Hikurangi subduction margin offshore New Zealand. These data show the distribution of vertical seafloor deformation during the SSE and reveal direct evidence for SSEs occurring close to the trench (within 2 kilometers of the seafloor), where very low temperatures and pressures exist
Evidence for Past Subduction Earthquakes at a Plate Boundary with Widespread Upper Plate Faulting: Southern Hikurangi Margin, New Zealand
At the southern Hikurangi margin, New Zealand, we use salt marsh stratigraphy, sedimentology, micropaleontology, and radiocarbon dating to document evidence of two earthquakes producing coseismic subsidence and (in one case) a tsunami over the past 1000 yrs. The earthquake at 520-470 yrs before present (B.P.) produced 0.25 +/- 0.1 m of subsidence at Big Lagoon. The earthquake at 880-800 yrs B.P. produced 0.45 +/- 0.1 m of subsidence at Big Lagoon and was accompanied by a tsunami that inundated >= 360 m inland with a probable height of >= 3.3 m. Distinguishing the effects of upper plate faulting from plate interface earthquakes is a significant challenge at this margin. We use correlation with regional upper plate paleoearthquake chronologies and elastic dislocation modeling to determine that the most likely cause of the subsidence and tsunami events is subduction interface rupture, although the older event may have been a synchronous subduction interface and upper plate fault rupture. The southern Hikurangi margin has had no significant (M > 6.5) documented subduction interface earthquakes in historic times, and previous assumptions that this margin segment is prone to rupture in large to great earthquakes were based on seismic and geodetic evidence of strong contemporary plate coupling. This is the first geologic evidence to confirm that the southern Hikurangi margin ruptures in large earthquakes. The relatively short-time interval between the two subduction earthquakes (similar to 350 yrs) is shorter than in current seismic-hazard models.GNSEQC Biennial ProjectNew Zealand Natural Hazards Research Platform and Foundation for Research Science and TechnologyInstitute for Geophysic
Continental breakup and UHP rock exhumation in action: GPS results from the Woodlark Rift, Papua New Guinea
We show results from a network of campaign Global Positioning System (GPS) sites in the Woodlark Rift, southeastern Papua New Guinea, in a transition from seafloor spreading to continental rifting. GPS velocities indicate anticlockwise rotation (at 2–2.7°/Myr, relative to Australia) of crustal blocks north of the rift, producing 10–15 mm/yr of extension in the continental rift, increasing to 20–40 mm/yr of seafloor spreading at the Woodlark Spreading Center. Extension in the continental rift is distributed among multiple structures. These data demonstrate that low-angle normal faults in the continents, such as the Mai'iu Fault, can slip at high rates nearing 10 mm/yr. Extensional deformation observed in the D'Entrecasteaux Islands, the site of the world's only actively exhuming Ultra-High Pressure (UHP) rock terrane, supports the idea that extensional processes play a critical role in UHP rock exhumation. GPS data do not require significant interseismic coupling on faults in the region, suggesting that much of the deformation may be aseismic. Westward transfer of deformation from the Woodlark Spreading Center to the main plate boundary fault in the continental rift (the Mai'iu fault) is accommodated by clockwise rotation of a tectonic block beneath Goodenough Bay, and by dextral strike slip on transfer faults within (and surrounding) Normanby Island. Contemporary extension rates in the Woodlark Spreading Center are 30–50% slower than those from seafloor spreading-derived magnetic anomalies. The 0.5 Ma to present seafloor spreading estimates for the Woodlark Basin may be overestimated, and a reevaluation of these data in the context of the GPS rates is warranted
Assessment of the wintering area of Red Knots in Maranhão, northern Brazil, in February 2005
To assess population size and the conservation status of the Red Knot Calidris canutus rufa population in Maranhão, N Brazil, an aerial census and field studies were conducted in February 2005. The aerial count showed a population of 7,575 Knots, which is down about 600 from a previous census in the 1980s. However, the count for all shorebird species combined was only 24,000 compared to 198,600 in the 1980s, paralleling a world-wide trend of population decline in shorebirds. Resightings of colour-banded knots confirmed that this is a separate population from the larger wintering population in Tierra del Fuego. All species of shorebirds captured in Maranhão were found to be infested with feather lice and mites. Body masses of knots in Maranhão were significantly lower than in Tierra del Fuego, and about half the birds were below the hypothesized fat-free mass of the species. Blood and feather samples were taken from 38 Knots for subsequent assessment of virus loads, and for detecting sites where primary feather moult had occurred. This will enable us to establish whether significant mortality is associated with pathogen loads and the energetic demands of delayed moulting. The small size of the Maranhão population and the loss of another 13,000 knots this winter from the Tierra del Fuego population means that both are now endangered. Brochures on the need for Red Knot conservation were designed and printed, and have been circulated among fishing communities and school classes in Maranhão.Fil: Baker,Allan J.. Royal Ontario Museum; CanadáFil: González, Patricia M.. Fundación Inalafquen; ArgentinaFil: Serrano, Ines L.. CEMAVE, Centro Nacional de Pesquisa para Conservação das Aves Silvestres; BrasilFil: Júnior, Wallace R. T.. CEMAVE, Centro Nacional de Pesquisa para Conservação das Aves Silvestres; BrasilFil: Efe, Marcio A.. Universidade Federal de Alagoas; BrasilFil: Rice, Susan. Eastern Shore of Virginia National Wildlife Refuge; Estados UnidosFil: D'amico, Veronica Laura. Consejo Nacional de Investigaciones CientÃficas y Técnicas. Centro CientÃfico Tecnológico Conicet - Centro Nacional Patagónico; ArgentinaFil: Rocha, Marcia C.. Belém, Pará; BrasilFil: Echave, MarÃa Eugenia. Fundación Inalafquen; Argentin
Rapid microplate rotations and backarc rifting at the transition between collision and subduction
ABSTRACT Using global positioning system velocities from convergent plate boundaries in Papua New Guinea, New Zealand, Tonga, Vanuatu, and the Marianas, we note a spatial correlation between rapid tectonic block rotations and the transition from subduction to collision. We present a mechanism for the block rotations, in which the change from collision of a buoyant indentor to normal subduction exerts a torque on the upper-plate microplate. This work improves our understanding of the causes of rapid vertical axis rotations, often observed in paleomagnetic studies. We also show how collision-induced rotations may lead to backarc rifting
Transcriptional profiling reveals extraordinary diversity among skeletal muscle tissues
Skeletal muscle comprises a family of diverse tissues with highly specialized functions. Many acquired diseases, including HIV and COPD, affect specific muscles while sparing others. Even monogenic muscular dystrophies selectively affect certain muscle groups. These observations suggest that factors intrinsic to muscle tissues influence their resistance to disease. Nevertheless, most studies have not addressed transcriptional diversity among skeletal muscles. Here we use RNAseq to profile mRNA expression in skeletal, smooth, and cardiac muscle tissues from mice and rats. Our data set, MuscleDB, reveals extensive transcriptional diversity, with greater than 50% of transcripts differentially expressed among skeletal muscle tissues. We detect mRNA expression of hundreds of putative myokines that may underlie the endocrine functions of skeletal muscle. We identify candidate genes that may drive tissue specialization, including Smarca4, Vegfa, and Myostatin. By demonstrating the intrinsic diversity of skeletal muscles, these data provide a resource for studying the mechanisms of tissue specialization
Importance of external quality assessment for SARS-CoV-2 antigen detection during the COVID-19 pandemic
Background: Antigen testing has become an essential part of fighting the ongoing COVID-19 pandemic. With the continual increase in available tests, independent and extensive comparative evaluations using data from external quality assessment (EQA) studies to evaluate test performance between different users are required.Objectives: An EQA scheme was established to assess the sensitivity of antigen tests and the potential impact of circulating SARS-CoV-2 strains on their performance.Study design: Panels were prepared for three challenges in 2021 containing inactivated SARS-CoV-2-positive samples of various genetic strains (including variants of concern, VOCs) at different concentrations, and negative samples. Data was analysed based on qualitative testing results in relation to the antigen test used. Results: Participants registered for each individual challenge in any combination. In total, 258 respondents from 27 countries worldwide were counted submitting 472 datasets. All core samples were correctly reported by 76.7 to 83.1% at participant level and by 73.5 to 83.8% at dataset level. Sensitivity differences could be shown in viral loads and SARS-CoV-2 strains/variants including the impact on performance by a B.1.1.7-like mutant strain with a deletion in the nucleoprotein gene. Lateral flow rapid antigen tests showed a higher rate of false negatives in general compared with automated point-of-care tests and laboratory ELISA/immunoassays.Conclusions: EQA schemes can provide valuable data to inform participants about weaknesses in their testing process or methods and support ongoing assay evaluations for regulatory approval or post-market surveillance
Integrating the little talks intervention into Early Head Start: An experimental examination of implementation supports involving fidelity monitoring and performance feedback
Enriching home visiting services by incorporating scientifically-supported interventions is a means for improving their effectiveness in promoting child development. However, deliberate efforts to ensure that home visitors are fully knowledgeable and supported to implement interventions with parents of young children are necessary. In this experimental study, a randomly-assigned group of Early Head Start home visitors monitored the fidelity of their provision of a scientifically-based intervention, Little Talks, and the program\u27s general child development services. On a bi-weekly basis, home visitors received performance feedback specific to their implementation of Little Talks and based upon the fidelity data. Findings demonstrated that home visitors showed immediate and consistent mastery of the Little Talks content, while the quality of their implementation, including their clinical decision-making and collaborative processes, improved to adequate levels over time. The Little Talks home visitors showed generalized improvements in their ability to obtain Parent Input while providing the program\u27s typical child development services were detected. In fact, Little Talks home visitors\u27 were superior in obtaining Parent Input relative to comparison home visitors. Further, parents for whom low-quality intervention implementation was observed discontinued their enrollment in home visiting prematurely, while high-quality implementation was associated with sustained enrollment. Limitations for this study are identified, leading to future directions for advancing home visitors\u27 incorporation of evidence-based practices
Which interventions work for dementia family carers?: an updated systematic review of randomized controlled trials of carer interventions
Objective: The aim of this study was to update the literature on interventions for carers of people with dementia published between 2006 and 2016 and evaluate the efficacy of psychoeducational programmes and psychotherapeutic interventions on key mental health outcomes (depression, anxiety, burden, and quality of life). Methods: A meta-analysis was carried out of randomised controlled trials of carer interventions using MEDLINE, PsycINFO, Scopus, and Cochrane Central Register of Controlled Trials. Results: The majority of studies were conducted in Western and Southern Europe or the United States and recruited carers of people with Alzheimer’s disease or dementia grouped as a whole. The most commonly used outcome measures were depression and burden across studies. The updated evidence suggested that psychoeducation-skill building interventions delivered face-to-face can better impact on burden. Psychotherapeutic interventions underpinned by Cognitive Behaviour Therapy (CBT) models demonstrated strong empirical support for treating anxiety and depression and these effects were not affected by the mode of delivery (i.e., face-to-face vs technology). A modern CBT approach, Acceptance and Commitment Therapy (ACT), seemed to be particularly beneficial for carers experiencing high levels of anxiety. Conclusions: Future research needs to explore the efficacy of interventions on multiple clinical outcomes and which combination of interventions (components) would have the most significant effects when using CBT. The generalisation of treatment effects in different countries and carers of different types of dementia also need to be addressed. More research is needed to test the efficacy of modern forms of CBT such as ACT. 246/250 word
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