2,139 research outputs found
z~2: An Epoch of Disk Assembly
We explore the evolution of the internal gas kinematics of star-forming
galaxies from the peak of cosmic star-formation at to today.
Measurements of galaxy rotation velocity , which quantify ordered
motions, and gas velocity dispersion , which quantify disordered
motions, are adopted from the DEEP2 and SIGMA surveys. This sample covers a
continuous baseline in redshift from to , spanning 10 Gyrs. At
low redshift, nearly all sufficiently massive star-forming galaxies are
rotationally supported (). By , the percentage of
galaxies with rotational support has declined to 50 at low stellar mass
() and 70 at high stellar mass
(). For , the percentage
drops below 35 for all masses. From to now, galaxies exhibit
remarkably smooth kinematic evolution on average. All galaxies tend towards
rotational support with time, and it is reached earlier in higher mass systems.
This is mostly due to an average decline in by a factor of 3 since a
redshift of 2, which is independent of mass. Over the same time period,
increases by a factor of 1.5 for low mass systems, but does not
evolve for high mass systems. These trends in and with
time are at a fixed stellar mass and should not be interpreted as evolutionary
tracks for galaxy populations. When galaxy populations are linked in time with
abundance matching, not only does decline with time as before, but
strongly increases with time for all galaxy masses. This enhances the
evolution in . These results indicate that is a
period of disk assembly, during which the strong rotational support present in
today's massive disk galaxies is only just beginning to emerge.Comment: 12 pages, 8 figures, submitted to Ap
The role of pain-related anxiety in adolescents' disability and social impairment: ALSPAC data
Background Anxiety, in particular pain-related anxiety, plays an important role in explaining the severity of pain complaints and pain-related disability in both adults and children with chronic pain. The fear-avoidance model (FAM) describes how pain-related anxiety plays a critical role in the maintenance of pain-avoidance behaviour, which in turn influences pain-related disability. However, the FAM does not take into account broader aspects of adolescence, such as social functioning, which could be negatively impacted by anxiety. In addition, most studies examining the role of anxiety in pain have used small convenience or clinical samples. By using a large UK epidemiological database, this study investigated the associations between pain-related anxiety, disability and judgements of social impairment. Methods Participants (n = 856) with recurrent pain were selected from a larger epidemiological study (Avon Longitudinal Study of Parents and Children) of adolescents attending a research clinic at the age of 17 (n = 5170). Adolescents completed a self-report questionnaire on pain-related anxiety, disability and perceived social impairment. Results High levels of pain-related anxiety were associated with more disability. In girls, higher levels of pain-related anxiety were also related to the self-perception of greater impairment in social functioning compared with their peers. Conclusions Pain-related anxiety was associated with greater pain-related disability and impaired social functioning. Social functioning should be explored as an integral part of fear-avoidance models of adolescent chronic pain. © 2014 European Pain Federation-EFIC®
Eosinophils Are Important for Protection, Immunoregulation and Pathology during Infection with Nematode Microfilariae
Eosinophil responses typify both allergic and parasitic helminth disease. In helminthic disease, the role of eosinophils can be both protective in immune responses and destructive in pathological responses. To investigate whether eosinophils are involved in both protection and pathology during filarial nematode infection, we explored the role of eosinophils and their granule proteins, eosinophil peroxidase (EPO) and major basic protein-1 (MBP-1), during infection with Brugia malayi microfilariae. Using eosinophil-deficient mice (PHIL), we further clarify the role of eosinophils in clearance of microfilariae during primary, but not challenge infection in vivo. Deletion of EPO or MBP-1 alone was insufficient to abrogate parasite clearance suggesting that either these molecules are redundant or eosinophils act indirectly in parasite clearance via augmentation of other protective responses. Absence of eosinophils increased mast cell recruitment, but not other cell types, into the broncho-alveolar lavage fluid during challenge infection. In addition absence of eosinophils or EPO alone, augmented parasite-induced IgE responses, as measured by ELISA, demonstrating that eosinophils are involved in regulation of IgE. Whole body plethysmography indicated that nematode-induced changes in airway physiology were reduced in challenge infection in the absence of eosinophils and also during primary infection in the absence of EPO alone. However lack of eosinophils or MBP-1 actually increased goblet cell mucus production. We did not find any major differences in cytokine responses in the absence of eosinophils, EPO or MBP-1. These results reveal that eosinophils actively participate in regulation of IgE and goblet cell mucus production via granule secretion during nematode-induced pathology and highlight their importance both as effector cells, as damage-inducing cells and as supervisory cells that shape both innate and adaptive immunity
Transitioning cell culture CURE labs from campus to online: Novel strategies for a novel time
Course-based undergraduate research experiences (CUREs) provide a way for students to gain research experience in a classroom setting. Few examples of cell culture CUREs or online CUREs exist in the literature. The Cell Biology Education Consortium (CBEC) provides a network and resources for instructors working to incorporate cell-culture based research into the classroom. In this article, we provide examples from six instructors from the CBEC network on how they structure their cell-culture CUREs and how they transitioned the labs to online in the spring semester of 2020. We intend for these examples to provide instructors with ideas for strategies to set up cell culture CUREs, how to change that design mid-term, and for creating online CUREs in the future
Benefits and factors influencing the design of intergenerational digital games
The main purpose of this paper is to review the benefits and factors to be taken into
consideration for the design of intergenerational digital games. We conducted a systematic in Scopus,
Web of Science, PsicInfo, Pubmed and Science Direct, finally including 16 empirical studies written in
English. The identified benefits were found to fall into four main categories, i.e., (1) reinforcing family
bond, (2) enhancing reciprocal learning (3) increasing understanding of the other generation and
(4) reducing social anxiety. According to the literature, two types of factors are important to take into
consideration: player-centric and game-centric factors. We identified the nature of the interactions
between older (55â81 year-olds) and younger players (4â22 year-olds), their motivations to play
digital games and the difference in abilities as the main player-centric factors to take into account
when designing intergenerational games. The most relevant game-centric factors were found to be
goal-related and space-related forms of interaction. To gain more insight into how specific benefits
of playing digital games are related to a type of game, gender or age of the participant, additional
empirical studies (comparative analyses), that take these factors into account are needed
Distinguishing Mergers and Disks in High Redshift Observations of Galaxy Kinematics
The majority of massive star-forming galaxies at have velocity
gradients suggestive of rotation, in addition to large amounts of disordered
motions. In this paper, we demonstrate that it is challenging to distinguish
the regular rotation of a disk galaxy from the orbital motions of merging
galaxies with seeing-limited data. However, the merger fractions at
are likely too low for this to have a large effect on measurements of disk
fractions. To determine how often mergers pass for disks, we look to galaxy
formation simulations. We analyze 24000 synthetic images and kinematic
maps of 31 high-resolution simulations of isolated galaxies and mergers at
. We determine if the synthetic observations pass criteria commonly
used to identify disk galaxies, and whether the results are consistent with
their intrinsic dynamical states. Galaxies that are intrinsically mergers pass
the disk criteria for anywhere from 0 to 100 of sightlines. The exact
percentage depends strongly on the specific disk criteria adopted, and weakly
on the separation of the merging galaxies. Therefore, one cannot tell with
certainty whether observations of an individual galaxy indicate a merger or a
disk. To estimate the fraction of mergers passing as disks in current
kinematics samples, we combine the probability that a merger will pass as a
disk with theoretical merger fractions from a cosmological simulation. Taking
the latter at face-value, the observed disk fractions are overestimated by
small amounts: at most by at high stellar mass ( M)
and at low stellar mass ( M).Comment: 15 pages, 10 figures, accepted for publication in Ap
Contributions of myofascial pain in diagnosis and treatment of shoulder pain. A randomized control trial
<p>Abstract</p> <p>Background</p> <p>Rotator cuff tendinopathy and subacromial impingement syndrome present complex patomechanical situations, frequent difficulties in clinical diagnosis and lack of effectiveness in treatment. Based on clinical experience, we have therefore considered the existence of another pathological entity as the possible origin of pain and dysfunction. The hypothesis of this study is to relate subacromial impingement syndrome (SIS) with myofascial pain syndrome (MPS), since myofascial trigger points (MTrPs) cause pain, functional limitation, lack of coordination and alterations in quality of movement, even prior to a tendinopathy. MTrPs can coexist with any degenerative subacromial condition. If they are not taken into consideration, they could perpetuate and aggravate the problem, hindering diagnosis and making the applied treatments ineffective.</p> <p>The aims and methods of this study are related with providing evidence of the relationship that may exist between this condition and MPS in the diagnosis and treatment of rotator cuff tendonitis and/or SIS.</p> <p>Method/design</p> <p>A descriptive transversal study will be made to find the correlation between the diagnosis of SIS and rotator cuff tendonitis, positive provocation test responses, the existence of active MTrPs and the results obtained with ultrasonography (US) and Magnetic Renonance Imaging (MRI). A randomized double blinded clinical trial will be carried out in experimental conditions: A Protocolized treatment based on active and passive joint repositioning, stabilization exercises, stretching of the periarticular shoulder muscles and postural reeducation. B. The previously described protocolized treatment, with the addition of dry needling applied to active MTrPs with the purpose of isolating the efficacy of dry needling in treatment.</p> <p>Discussion</p> <p>This study aims to provide a new vision of shoulder pain, from the perspective of MPS. This syndrome can, by itself, account for shoulder pain and dysfunction, although it can coexist with real conditions involving the tendons.</p> <p>Trail Registration</p> <p>ISRCTN Number: 30907460</p
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