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Organization, atmosphere, and digital technologies: designing sensory order
We argue technology and organization are inherently spatial phenomenon. We conceptualize this conjunction as atmosphere: a gathering of mood, human practice, material and environmental conditions, and values that has sufficient coherence and distinction to constitute a distinct interior. Atmospheres, however, are not entirely stable and present: the interior is porous to outside influence, and the interior is never wholly ordered. We show this through the study of digitally mediated architectural design practice. We find the technological mediation of atmospheres is constituted in sensory and affective spatial arrangements, and not in rationally calculated configurations of assets and goals. An atmosphere is inherently aesthetic. This allows us to gesture toward a definition of organization as technologically mediated spatial struggle to reconcile interior coherence with outward exposure
Deep-diving by narwhals Monodon monoceros: differences in foraging behavior between wintering areas?
Methanol maps of low-mass protostellar systems: the Serpens Molecular Core
Observations of Serpens have been performed at the JCMT using Harp-B. Maps
over a 4.5'x5.4' region were made in a frequency window around 338 GHz,
covering the 7-6 transitions of methanol. Emission is extended over each
source, following the column density of H2 but showing up also particularly
strongly around outflows. The rotational temperature is low, 15-20 K, and does
not vary with position within each source. The abundance is typically 10^-9 -
10^-8 with respect to H2 in the outer envelope, whereas "jumps" by factors of
up to 10^2 -10^3 inside the region where the dust temperature exceeds 100 K are
not excluded. A factor of up to ~ 10^3 enhancement is seen in outflow gas. In
one object, SMM4, the ice abundance has been measured to be ~ 3x10^-5 with
respect to H2 in the outer envelope, i.e., a factor of 10^3 larger than the
gas-phase abundance. Comparison with C18O J=3-2 emission shows that strong CO
depletion leads to a high gas-phase abundance of CH3OH not just for the Serpens
sources, but for a larger sample of protostars. The observations illustrate the
large-scale, low-level desorption of CH3OH from dust grains, extending out to
and beyond 7500 AU from each source, a scenario which is consistent with
non-thermal (photo-)desorption from the ice. The observations also illustrate
the usefulness of CH3OH as a tracer of energetic input in the form of outflows,
where methanol is sputtered from the grain surfaces. Finally, the observations
provide further evidence of CH3OH formation through CO hydrogenation proceeding
on grain surfaces in low-mass envelopes.Comment: Accepted for publication in A&A
Dynamical structure of the inner 100 AU of the deeply embedded protostar IRAS 16293-2422
A fundamental question about the early evolution of low-mass protostars is
when circumstellar disks may form. High angular resolution observations of
molecular transitions in the (sub)millimeter wavelength windows make it
possible to investigate the kinematics of the gas around newly-formed stars,
for example to identify the presence of rotation and infall. IRAS 16293-2422
was observed with the extended Submillimeter Array (eSMA) resulting in
subarcsecond resolution (0.46" x 0.29", i.e. 55 35~AU) images
of compact emission from the CO (3-2) and CS (7-6) transitions at
337~GHz (0.89~mm). To recover the more extended emission we have combined the
eSMA data with SMA observations of the same molecules. The emission of
CO (3-2) and CS (7-6) both show a velocity gradient oriented
along a northeast-southwest direction with respect to the continuum marking the
location of one of the components of the binary, IRAS16293A. Our combined eSMA
and SMA observations show that the velocity field on the 50--400~AU scales is
consistent with a rotating structure. It cannot be explained by simple
Keplerian rotation around a single point mass but rather needs to take into
account the enclosed envelope mass at the radii where the observed lines are
excited. We suggest that IRAS 16293-2422 could be among the best candidates to
observe a pseudo-disk with future high angular resolution observations.Comment: Accepted for publication in ApJ, 18 pages, 10 figure
Abundance and distribution of narwhals (Monodon monoceros) on the summering grounds in Greenland between 2007-2019
Narwhal abundance in West Greenland (WG) and East Greenland (EG) was estimated from aerial surveys conducted between 2007 and 2019 at their summer grounds. Analyses were completed using Mark Recapture Distance Sampling and Hidden Markov Line Transect Models taking account of the stochastic availability of diving whales. No statistically significant difference in abundance of narwhals could be detected for the two summer grounds (Melville Bay and Inglefield Bredning) in WG between 2007 and 2019. The distribution of narwhals in Inglefield Bredning was similar between years but in Melville Bay, area usage has decreased >80% since the first survey in 2007. Few detections of narwhals were obtained during the surveys in EG and a common detection function was fitted from combining sightings from seven surveys. Narwhals were found in small aggregations distributed between Nordostrundingen and south to and including Tasiilaq. Abundance of narwhals was estimated for the first time in the relatively unexplored Northeast Greenland (Dove Bay and a restricted coastal area of the Greenland Sea). The abundance in these two areas was 2908 narwhals (CV=0.30; 95% CI:1639-5168) estimated in 2017 for the Greenland Sea and 2297 (0.38; 1123-4745) and 1395 (0.33; 744-2641) narwhals were estimated for Dove Bay in 2017 and 2018, respectively. Both abundance and distribution range of narwhals in Southeast Greenland, where narwhals are subject to subsistence harvest, has decreased significantly between 2008-2017 and narwhals have even disappeared at the southernmost area since the first surveys in 2008.Peer reviewe
Reactions of Narwhals, Monodon monoceros, to Killer Whale, Orcinus orca, Attacks in the Eastern Canadian Arctic
A Killer Whale attack on Narwhals was observed at Kakiak Point in Admiralty Inlet, Nunavut, Canada, in August 2005. Behavioral responses of both Narwhals and Killer Whales were documented by direct observation. Data collected from Narwhals instrumented with satellite-linked transmitters 5 days prior to the arrival of Killer Whales were used to examine changes in Narwhal movement patterns (e.g., dispersal and clumping) five days before the attack, during the attack, and five days after Killer Whales left the area. A minimum of four Narwhals were killed by 12-15 Killer Whales in a period of 6 hours. Narwhals showed a suite of behavioral changes in the immediate presence of Killer Whales including slow, quiet movements, travel close to the beach (<2 m from shore), use of very shallow water, and formation of tight groups at the surface. These behavioral changes are consistent with Inuit accounts of Killer Whale attacks on Narwhals. During the attack, Narwhals dispersed broadly, the groups were less clumped (standard deviation of inter-whale mean latitudes and longitudes), Narwhal space-use doubled from pre-attack home ranges of 347 km2 to 767 km2 (kernel 50% probability), and Narwhals shifted their distribution further south of the attack site. After the disappearance of Killer Whales, north-south dispersal of Narwhals contracted and was similar to pre-attack levels, total space use decreased slightly (599 km2), yet west-east dispersal remained high. Narwhals were distributed significantly (P < 0.001) more broadly offshore in areas not used before the occurrence of Killer Whales. In general, short-term reactions of Narwhals to Killer Whale presence were obvious; yet normal behavior (as observed from shore) resumed shortly after Killer Whales left the area. Long-term (five day) Narwhal behavioral responses included increased dispersal of Narwhal groups over large offshore areas. This is among the few reports of eyewitness Killer Whale attacks on Narwhals in the high Arctic and is the first time changes in Narwhal behavior have been documented in response to a predation event through the use of satellite telemetry
Investigation of early signs of peripheral artery disease in patients with schizophrenia using toe-brachial index
INTRODUCTION: Patients with schizophrenia have a reduced life expectancy compared to the general population, and cardiovascular diseases contribute to this. Peripheral arterial disease (PAD) is associated with excess all-cause mortality and specifically with cardiovascular morbidity and mortality. The risk factors for PAD, such as diabetes, smoking, hypertension, dyslipidaemia and obesity, are more common among patients with schizophrenia which could contribute to a possibly higher prevalence of PAD among patients with schizophrenia. OBJECTIVES: To investigate PAD utilizing toe brachial index (TBI) in a population of patients diagnosed with schizophrenia with the purpose of establishing prevalence rates amongst newly diagnosed as well as more chronic patients. METHODS: A cross-sectional study of patients with schizophrenia (ICD10-diagnosis F20 or F25) with a study population of 57 patients diagnosed with schizophrenia within the last 2 years, psychiatric healthy controls matched by age, sex and smoking status and 142 patients with a schizophrenia diagnosis more than 10 years ago. The primary outcome is TBI in patients with schizophrenia stratified to the two subpopulations. The TBI will be calculated from the arm and toe systolic pressures. The toe pressures were measured using photoplethysmography (SysToe®, Atys Medical). RESULTS: No results are available yet. The cohort will be described by age, sex, smoking status, body fat percentage and physical comorbidities. The TBI of the two subpopulations will be compared with psychiatrically healthy controls using paired t-tests if data is normally distributed. If transformation is unsuitable, Wilcoxon test will be carried out instead. CONCLUSIONS: No results are available yet. Results will be presented at the EPA’s congress 2021. DISCLOSURE: No significant relationships
Star and Planet Formation with ALMA: an Overview
Submillimeter observations with ALMA will be the essential next step in our
understanding of how stars and planets form. Key projects range from detailed
imaging of the collapse of pre-stellar cores and measuring the accretion rate
of matter onto deeply embedded protostars, to unravelling the chemistry and
dynamics of high-mass star-forming clusters and high-spatial resolution studies
of protoplanetary disks down to the 1 AU scale.Comment: Invited review, 8 pages, 5 figures; to appear in the proceedings of
"Science with ALMA: a New Era for Astrophysics". Astrophysics & Space
Science, in pres
Convex optimization problem prototyping for image reconstruction in computed tomography with the Chambolle-Pock algorithm
The primal-dual optimization algorithm developed in Chambolle and Pock (CP),
2011 is applied to various convex optimization problems of interest in computed
tomography (CT) image reconstruction. This algorithm allows for rapid
prototyping of optimization problems for the purpose of designing iterative
image reconstruction algorithms for CT. The primal-dual algorithm is briefly
summarized in the article, and its potential for prototyping is demonstrated by
explicitly deriving CP algorithm instances for many optimization problems
relevant to CT. An example application modeling breast CT with low-intensity
X-ray illumination is presented.Comment: Resubmitted to Physics in Medicine and Biology. Text has been
modified according to referee comments, and typos in the equations have been
correcte
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