We studied the latency and amplitude of the pupillary light reflex response of the Royal College of Surgeons rat from 10 to 52 weeks of age. The responses of these dystrophic rats were diminished ...compared to those of normal, non-dystrophic rats at all ages examined. This was most marked at the dimmest light intensity studied here and for the latency of dystrophic animals' responses. The latency deteriorated over the course of 52 weeks, although there was some evidence of improvement beyond 36 weeks of age. The amplitude of the dystrophic animals' responses also suggested some deterioration occurring up to 36 weeks of age, but with a substantial improvement beyond this time. In addition to these parameters, we also observed a break in the constriction phase of the pupillary light reflex that was unique to the dystrophic animals' responses. The frequency with which the anomaly occurred decreased in a light-dependent manner with age. The improvement of the pupillary light reflex at older ages, even when very few photoreceptors remain, may reflect compensatory events occurring in the inner retinal layers and/or in the central connections of the pupillary light reflex pathway. We suggest that the break in the constriction phase is a reflection of dual inputs driving the response, one of which is affected more by the degenerative events. This study provides baseline data on the effect of degeneration on function over time which can be used to evaluate the efficacy of repair strategies such as transplantation.
We develop a kinematic model for the transition from subduction beneath the North Island, New Zealand, to strike‐slip in the South Island, constrained by GPS velocities and active fault slip data. To ...interpret these data, we use an approach that inverts the kinematic data for poles of rotation of tectonic blocks and the degree of interseismic coupling on faults in the region. Convergence related to the Hikurangi subduction margin becomes very low offshore of the northern South Island, indicating that in this region the majority of the relative plate motion has been transferred onto faults within the upper plate, as suggested by previous studies. This result has implications for understanding the likely extent of subduction interface earthquake rupture in central New Zealand. Easterly trending strike slip faults (such as the Boo Boo fault) are the key features that facilitate the transfer of strike‐slip motion from the northern South Island faults further north into the southern North Island and onto the Hikurangi subduction thrust. Our results also indicate that the transition from rapid forearc rotation adjacent to the Hikurangi subduction margin to a strike‐slip dominated plate boundary (with negligible vertical‐axis rotation) in the South Island occurs via a crustal‐scale hinge or kink in the upper plate, compatible with paleomagnetic and structural geological data. Despite the ongoing tectonic evolution of the central New Zealand region, our study highlights a remarkable consistency between data sets spanning decades (GPS), thousands of years (active faulting data), and millions of years (paleomagnetic data and bedrock structure).
Key Points
Active fault and GPS data used to constrain strike‐slip to subduction in NZ
Excellent agreement between short‐term (GPS) and longer‐term (active fault) data
New model for subduction interface coupling at Hikurangi margin
A model of active faulting in New Zealand Litchfield, NJ; Van Dissen, R; Sutherland, R ...
New Zealand journal of geology and geophysics,
01/2014, Letnik:
57, Številka:
1
Journal Article
Recenzirano
Odprti dostop
Active fault traces are a surface expression of permanent deformation that accommodates the motion within and between adjacent tectonic plates. We present an updated national-scale model for active ...faulting in New Zealand, summarize the current understanding of fault kinematics in 15 tectonic domains, and undertake some brief kinematic analysis including comparison of fault slip rates with GPS velocities. The model contains 635 simplified faults with tabulated parameters of their attitude (dip and dip-direction) and kinematics (sense of movement and rake of slip vector), net slip rate and a quality code. Fault density and slip rates are, as expected, highest along the central plate boundary zone, but the model is undoubtedly incomplete, particularly in rapidly eroding mountainous areas and submarine areas with limited data. The active fault data presented are of value to a range of kinematic, active fault and seismic hazard studies.
We measure the horizontal (|cos(
θ
z
)|<0.14 corresponding to a slant depth cut 14 kmwe) neutrino-induced muon flux (
E
μ>1.8 GeV) in Soudan 2 to be 4.01
±
0.50
±
0.30
×
10
−13 cm
−2
sr
−1
s
−1. From ...the absence of horizontal muons with large energy loss, we set a limit on the flux of muon neutrinos from active galactic nuclei.
The New Zealand Active Faults Database Langridge, RM; Ries, WF; Litchfield, NJ ...
New Zealand journal of geology and geophysics,
01/2016, Letnik:
59, Številka:
1
Journal Article
Recenzirano
The New Zealand Active Faults Database (NZAFD) is a national geospatial database of active faults - including their locations, names and degrees of activity - that have deformed the ground surface of ...New Zealand within the last 125,000 years. The NZAFD is used for geological research, hazard modelling and infrastructure planning and is an underlying dataset for other nationally significant hazard applications such as the National Seismic Hazard Model. Recent refinements to the data structure have improved the accuracy of active fault locations and characteristics. A subset of active fault information from the NZAFD, generalised for portrayal and use at a scale of 1:250,000 (and referred to as NZAFD250), is freely available online and can be downloaded in several different formats to suit the needs of a range of users including scientists, governmental authorities and the general public. To achieve a uniform spatial scale of 1:250,000 a simplification of detailed fault locational data was required in some areas, while in other areas new mapping was necessary to provide a consistent level of coverage. Future improvements to the NZAFD will include the incorporation of data on active folds and offshore active faults.
Mechanisms driving resistance to cyclin-dependent kinase 4/6 inhibitors (CDK4/6i) in hormone receptor-positive (HR
) breast cancer have not been clearly defined. Whole-exome sequencing of 59 tumors ...with CDK4/6i exposure revealed multiple candidate resistance mechanisms including
loss, activating alterations in
, and
, and loss of estrogen receptor expression.
experiments confirmed that these alterations conferred CDK4/6i resistance. Cancer cells cultured to resistance with CDK4/6i also acquired
, or
alterations, which conferred sensitivity to AURKA, ERK, or CHEK1 inhibition. Three of these activating alterations-in
, and
-have not, to our knowledge, been previously demonstrated as mechanisms of resistance to CDK4/6i in breast cancer preclinically or in patient samples. Together, these eight mechanisms were present in 66% of resistant tumors profiled and may define therapeutic opportunities in patients. SIGNIFICANCE: We identified eight distinct mechanisms of resistance to CDK4/6i present in 66% of resistant tumors profiled. Most of these have a therapeutic strategy to overcome or prevent resistance in these tumors. Taken together, these findings have critical implications related to the potential utility of precision-based approaches to overcome resistance in many patients with HR
metastatic breast cancer.
.
Used for both proton decay searches and neutrino physics, large water Cherenkov (WC) detectors have been very successful tools in particle physics. They are notable for their large masses and charged ...particle detection capabilities. While current WC detectors reconstruct charged particle tracks over a wide energy range, they cannot efficiently detect neutrons. Gadolinium (Gd) has the largest thermal neutron capture cross section of all stable nuclei and produces an 8 MeV gamma cascade that can be detected with high efficiency. Because of the many new physics opportunities that neutron tagging with a Gd salt dissolved in water would open up, a large-scale R&D program called EGADS was established to demonstrate this technique’s feasibility. EGADS features all the components of a WC detector, chiefly a 200-ton stainless steel water tank furnished with 240 photo-detectors, DAQ, and a water system that removes all impurities from water while keeping Gd in solution. In this paper we discuss the milestones towards demonstrating the feasibility of this novel technique, and the features of EGADS in detail.
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