Geological interpretation of volcanism and segmentation of the Mariana back-arc spreading center between 12.7°N and 18.3°N

The relationships between tectonic processes, magmatism, and hydrothermal venting along ∼600 km of the slow-spreading Mariana back-arc between 12.7°N and 18.3°N reveal a number of similarities and differences compared to slow-spreading mid-ocean ridges. Analysis of the volcanic geomorphology and structure highlights the complexity of the back-arc spreading center. Here, ridge segmentation is controlled by large-scale basement structures that appear to predate back-arc rifting. These structures also control the orientation of the chains of cross-arc volcanoes that characterize this region. Segment-scale faulting is oriented perpendicular to the spreading direction, allowing precise spreading directions to be determined. Four morphologically distinct segment types are identified: dominantly magmatic segments (Type I); magmatic segments currently undergoing tectonic extension (Type II); dominantly tectonic segments (Type III); and tectonic segments currently undergoing magmatic extension (Type IV). Variations in axial morphology (including eruption styles, neovolcanic eruption volumes, and faulting) reflect magma supply, which is locally enhanced by cross-arc volcanism associated with N-S compression along the 16.5°N and 17.0°N segments. In contrast, cross-arc seismicity is associated with N-S extension and increased faulting along the 14.5°N segment, with structures that are interpreted to be oceanic core complexes—the first with high-resolution bathymetry described in an active back-arc basin. Hydrothermal venting associated with recent magmatism has been discovered along all segment types

Population status of the Chuck-will’s-widow (Caprimulgus carolinensis) in the Bahamas.

The Chuck-will’s-widow (Caprimulgus carolinensis) in the Bahama Islands has been regarded as a rare to uncommon winter visitor. We conducted breeding season surveys on the three largest northern islands (North Andros, Grand Bahama, and Great Abaco) to examine the status of this species. We encountered singing birds on most survey routes on all three islands, suggesting that sizeable breeding populations are widespread in the northern Bahamas with an aggregate estimate of 500–1,000 pairs. Our density estimates were somewhat less than those from the primary range in the United States, suggesting either a lower carrying capacity in the Bahama Islands or recently established populations that have yet to reach carrying capacity

Multisensory coding of angular head velocity in the retrosplenial cortex

To successfully navigate the environment, animals depend on their ability to continuously track their heading direction and speed. Neurons that encode angular head velocity (AHV) are fundamental to this process, yet the contribution of various motion signals to AHV coding in the cortex remains elusive. By performing chronic single-unit recordings in the retrosplenial cortex (RSP) of the mouse and tracking the activity of individual AHV cells between freely moving and head-restrained conditions, we find that vestibular inputs dominate AHV signaling. Moreover, the addition of visual inputs onto these neurons increases the gain and signal-to-noise ratio of their tuning during active exploration. Psychophysical experiments and neural decoding further reveal that vestibular-visual integration increases the perceptual accuracy of angular self-motion and the fidelity of its representation by RSP ensembles. We conclude that while cortical AHV coding requires vestibular input, where possible, it also uses vision to optimize heading estimation during navigation

Population status of chuck-will’s-widow (Caprimulgus carolinensis) in the bahamas

The Chuck-will’s-widow (Caprimulgus carolinensis) in the Bahama Islands has been regarded as a rare to uncommon winter visitor. We conducted breeding season surveys on the three largest northern islands (North Andros, Grand Bahama, and Great Abaco) to examine the status of this species. We encountered singing birds on most survey routes on all three islands, suggesting that sizeable breeding populations are widespread in the northern Bahamas with an aggregate estimate of 500–1,000 pairs. Our density estimates were somewhat less than those from the primary range in the United States, suggesting either a lower carrying capacity in the Bahama Islands or recently established populations that have yet to reach carrying capacity. Received 24 August 2009. Accepted 3 January 2010

Physical Activity and Symmetry Following Total Knee Arthroplasty: Results of a Pilot Randomized Trial

Objective This pilot trial examined a Physical Activity and Symmetry (PAS) intervention focused on common deficits of physical inactivity and joint loading asymmetry following total knee arthroplasty (TKA). Design Participants (n=60) were enrolled during routine physical therapy (PT) following TKA and randomized to the PAS intervention or an attention (ATT) control group. The PAS intervention included physical activity counseling and balance exercise to address joint loading symmetry; content was delivered during 2 sessions at the end of routine PT plus supplemental sessions 4-weeks and 8-weeks following PT. The ATT control condition included supplemental sessions at 4-weeks and 8-weeks focused on general evaluation of surgical recovery benchmarks. Primary outcomes were weekly minutes of moderate to vigorous physical activity (MVPA), measured with an accelerometer, and peak force loading symmetry (limb symmetry index; LSI) during a 10m walk, measured with a 3-sensor in-shoe device. General linear mixed models compared changes in outcomes between randomized groups at 3-month and 6-month follow-up. Results Both PAS and ATT groups increased MVPA, but there were no clinically meaningful between-group differences at 3- or 6-month follow-up (p>0.05). There were also no clinically meaningful between-group differences LSI at 3- or 6-month follow-up (p>0.05). Conclusion The PAS intervention did not yield improvements beyond ATT control. It is possible that PAS components were being delivered as part of routine PT, and a more intensive intervention (e.g., more visits, guidance for exercise progression) or targeted approach (e.g., those with deficits at end of routine care) may be needed to further improve outcomes

Abrogation of the radiation-induced G2 checkpoint by the staurosporine derivative UCN-01 is associated with radiosensitisation in a subset of colorectal tumour cell lines

Ionising radiation is commonly used in the treatment of colorectal cancer. Tumour cells with mutant p53 undergo cell cycle arrest at G2/M after ionising radiation and evidence suggests that abrogation of this G2 arrest can lead to a premature, aberrant mitosis, thus enhancing ionising radiation-induced cell killing. The G2 checkpoint inhibitor UCN-01 was thus investigated to determine whether it would abrogate the G2 checkpoint induced by 5 Gy ionising radiation in a range of colorectal tumour cell lines. Data presented show that, at doses that are alone non-toxic to the cells, UCN-01 inhibits the ionising radiation-induced G2 checkpoint in five colorectal tumour cell lines with mutant p53. The ability of UCN-01 to sensitise cells to ionising radiation-induced growth inhibition and apoptosis was also investigated and UCN-01 was found to radiosensitise two out of five cell lines. These results were confirmed by long-term colony forming efficiency studies. These results demonstrate that abrogation of the ionising radiation-induced G2 checkpoint is not necessarily associated with sensitisation to ionising radiation, however, some colorectal tumour cell lines can be radiosensitised by UCN-01. Although the mechanism of radiosensitisation is not clear, this may still be an important treatment strategy

JET machine operations in T&D-T

JET, the world's largest operating tokamak with unique Be/W wall and tritium handling capability, completed a Deuterium-Tritium (D-T) campaign in 2021 (Maggi et al 29th Fusion Energy Conf.) following a decade of preparatory experiments, dedicated enhancements, technical rehearsals and training (Horton et al 2016 Fusion Eng. Des. 109-111 925). Operation with tritium raises significant technical, safety and scientific challenges not encountered in standard protium or deuterium operation. This contribution describes the tritium operational requirements, pulses and technical preparations, new operating procedures, lessons learned and details on the achieved operational availability and performance. The preparation and execution of the recent JET tritium experiments benefitted from the previous experience in 1991 (Preliminary Tritium Experiment), 1997 (DTE1 campaign) and 2003 (Trace Tritium Campaigns) and consisted of the following five phases: technical rehearsals and scenario preparation, tritium commissioning, 100% tritium campaign, D-T campaign (DTE2), tritium clean-up. Following the clean-up JET resumed normal operation and is currently undertaking a further D-T campaign (DTE3)

Legitimising Emerging Power Diplomacy: an Analysis of Government and Media Discourses on Brazilian Foreign Policy under Lula

Abstract This study analyses whether Brazilian foreign policy under Lula successfully legitimised the country's international identity as a rising power in the eyes of the domestic and international media. Based on a constructivist framework, we have applied French Discourse Analysis to a corpus of 36 official addresses by the President of the Republic and the Minister of Foreign Relations and 137 news articles from four news outlets, two Brazilian and two international, concerning two diplomatic episodes deemed representative of Brazil's quest for greater pre-eminence: the leadership of MINUSTAH (2004) and the Nuclear Deal signed with Iran and Turkey (2010). Results show that official discourse characterises Brazil's identity as a rising power chiefly by South-South diplomacy, while media discourse was more heterogeneous, being the discursive formation of each news outlet determinant in explaining their interpretation of Brazil's international identity