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LanderPick, a Remote Operated Trawled Vehicle to cost-effectively deploy and recover lightweight oceanographic landers
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The QUEST RR Lyrae Survey: Confirmation of the Clump at 50 kpc and Other Over-Densities in the Outer Halo
We have measured the periods and light curves of 148 RR Lyrae variables from
V=13.5 to 19.7 from the first 100 sq. degrees of the QUEST RR Lyrae survey.
Approximately 55% of these stars belong to the clump of stars detected earlier
by the Sloan Digital Sky Survey. According to our measurements, this feature
has ~10 times the background density of halo stars, spans at least 37.5 deg by
3.5 deg in right ascension and declination (>=30 by >=3 kpc), lies ~50 kpc from
the Sun, and has a depth along the line of sight of ~5 kpc (1 sigma). These
properties are consistent with the recent models that suggest it is a tidal
stream from the Sgr dSph galaxy. The mean period of the type ab variables, 0.58
d, is also consistent. In addition, we have found two smaller over-densities in
the halo, one of which may be related to the globular cluster Pal 5.Comment: 12 pages (including 4 figures). Accepted for publication in the ApJ
Letter
LanderPick, a Remote Operated Trawled Vehicle to cost-effectively deploy and recover lightweight oceanographic landers.
Landers are modular structures equipped with miscellaneous sensors and monitoring equipment which are positioned directly on the seabed to operate autonomously for a defined timeframe. A drawback of landers intended to operate for prolonged periods in the deep ocean is the high cost of recovery systems, typically depending on buoyancy modules plus expendable ballast, or requiring ROVs assistance. LanderPick concept consists of the design of a specific trawled vehicle to deploy and recover lightweight oceanographic landers not provided with recovery elements, but having a capture mesh that facilitates their hitching. The LanderPick vehicle is technically a ROTV (Remote Operated Trawled Vehicle) controlled through a standard coaxial electromechanical cable that allows real-time control from the vessel. Navigation is enabled by a low-light high-definition camera, aided by spotlights and laser pointers. Small propellers aid in the final precision approach maneuvers. A mechanical release allows the precise placement at the sea bottom of landers carried as a payload, as well as their recovery by means of a triple hook. First sea missions of the system were carried out successfully in 2021 in southern Biscay. A 4-month deployment of a lander array equipped with current-meters along an energetic canyon axis provided unprecedented detail in the progression of the internal tidal bore. Short (48-hours) deployments of a fully-instrumented lander, including lapse-time image and baits in a deep seamount summit within a marine protected area, provided insights on the biodiversity of a unique ecosystem. The LanderPick novel approach to cost-effectively and precisely deploy and recover lightweight oceanographic landers allows to conceive (i) monitoring systems based on the deployment of arrays or fleets of low-cost landers and (ii) experiments associated with deep habitats such as coral reefs in which it is necessary to locate landers with great precision
Dissimilar Impact of a Mediterranean Diet and Physical Activity on Anthropometric Indices: A Cross-Sectional Study from the ILERVAS Project
There is a close relationship between lifestyle behaviors and excess adiposity. Although body mass index (BMI) is the most used approach to estimate excess weight, other anthropometric indices have been developed to measure total body and abdominal adiposity. However, little is known about the impact of physical activity and adherence to a Mediterranean diet on these indices. Here we report the results of a cross-sectional study with 6672 middle-aged subjects with low to moderate cardiovascular risk from the Ilerda Vascular (ILERVAS) project. The participants' adherence to physical activity (International Physical Activity Questionnaire short form) and MedDiet (Mediterranean Diet Adherence Screener) was evaluated. Measures of total adiposity (BMI, Clínica Universidad de Navarra-Body Adiposity Estimator (CUN-BAE), and Deurenberg's formula), central adiposity (waist and neck circumferences, conicity index, waist to height ratio, Bonora's equation, A body adiposity index, and body roundness index), and lean body mass (Hume formula) were assessed. Irrespective of sex, lower indices of physical activity were associated with higher values of total body fat and central adiposity. This result was constant regardless of the indices used to estimate adiposity. However, the association between MedDiet and obesity indices was much less marked and more dependent on sex than that observed for physical activity. Lean body mass was influenced by neither physical activity nor MedDiet adherence. No joint effect between physical activity and MedDiet to lower estimated total or central adiposity indices was shown. In conclusion, physical activity is related to lower obesity indices in a large cohort of middle-aged subjects. MedDiet showed a slight impact on estimated anthropometric indices, with no joint effect when considering both lifestyle variables
Discovery of the Optical Transient of the Gamma Ray Burst 990308
The optical transient of the faint Gamma Ray Burst 990308 was detected by the
QUEST camera on the Venezuelan 1-m Schmidt telescope starting 3.28 hours after
the burst. Our photometry gives , , , and for times ranging from 3.28 to 3.47
hours after the burst. The colors correspond to a spectral slope of close to
. Within the standard synchrotron fireball model,
this requires that the external medium be less dense than , the
electrons contain of the shock energy, and the magnetic field energy
must be less than 24% of the energy in the electrons for normal interstellar or
circumstellar densities. We also report upper limits of at 132 s
(with LOTIS), from 132-1029s (with LOTIS), at 28.2 min
(with Super-LOTIS), and a 8.5 GHz flux of at 110 days (with the
Very Large Array). WIYN 3.5-m and Keck 10-m telescopes reveal this location to
be empty of any host galaxy to and . The lack of a host
galaxy likely implies that it is either substantially subluminous or more
distant than a red shift of .Comment: ApJ Lett submitted, 5 pages, 2 figures, no space for 12 coauthor
Chikungunya virus infections among travellers returning to Spain, 2008 to 2014
Since the first documented autochthonous transmission of
chikungunya virus in the Caribbean island of Saint Martin in
2013, the infection has been reported within the Caribbean
region as well as North, Central and South America. The risk of
autochthonous transmission of chikungunya virus becoming
established in Spain may be elevated due to the large numbers of
travellers returning to Spain from countries affected by the
2013 epidemic in the Caribbean and South America, as well as the
existence of the Aedes albopictus vector in certain parts of
Spain. We retrospectively analysed the laboratory diagnostic
database of the National Centre for Microbiology, Institute of
Health Carlos III (CNM-ISCIII) from 2008 to 2014. During the
study period, 264 confirmed cases, of 1,371 suspected cases,
were diagnosed at the CNM-ISCIII. In 2014 alone, there were 234
confirmed cases. The highest number of confirmed cases were
reported from the Dominican Republic (n = 136), Venezuela (n =
30) and Haiti (n = 11). Six cases were viraemic in areas of
Spain where the vector is present. This report highlights the
need for integrated active case and vector surveillance in Spain
and other parts of Europe where chikungunya virus may be
introduced by returning travellers
Cytomolecular identification of individual wheat-wheat chromosome arm associations in wheat-rye hybrids
Chromosome pairing in the meiotic metaphase I of wheatrye
hybrids has been characterized by sequential genomic
and fluorescent in situ hybridization allowing not only the
discrimination of wheat and rye chromosomes, but also the
identification of the individual wheat and rye chromosome
arms involved in the chromosome associations. The majority
of associations (93.8%) were observed between the wheat
chromosomes. The largest number of wheat-wheat chromosome
associations (53%) was detected between the A and D
genomes, while the frequency of B-D and A-B associations
was significantly lower (32 and 8%, respectively). Among the
A-D chromosome associations, pairing between the 3AL and
3DL arms was observed with the highest frequency, while
the most frequent of all the chromosome associations (0.113/
cell) was found to be the 3DS-3BS. Differences in the pairing
frequency of the individual chromosome arms of wheat-rye
hybrids have been discussed in relation to the homoeologous
relationships between the constituent genomes of
hexaploid wheat
A High Statistics Measurement of the Lambdac+ Lifetime
A high statistics measurement of the Lambdac+ lifetime from the Fermilab
fixed-target FOCUS photoproduction experiment is presented. We describe the
analysis technique with particular attention to the determination of the
systematic uncertainty. The measured value of 204.6 +/- 3.4 (stat.) +/- 2.5
(syst.) fs from 8034 +/- 122 Lambdac -> pKpi decays represents a significant
improvement over the present world average.Comment: Submitted to Physical Review Letter
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