3,368 research outputs found

    A novel chromosome segregation mechanism during female meiosis.

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    In a wide range of eukaryotes, chromosome segregation occurs through anaphase A, in which chromosomes move toward stationary spindle poles, anaphase B, in which chromosomes move at the same velocity as outwardly moving spindle poles, or both. In contrast, Caenorhabditis elegans female meiotic spindles initially shorten in the pole-to-pole axis such that spindle poles contact the outer kinetochore before the start of anaphase chromosome separation. Once the spindle pole-to-kinetochore contact has been made, the homologues of a 4-Ī¼m-long bivalent begin to separate. The spindle shortens an additional 0.5 Ī¼m until the chromosomes are embedded in the spindle poles. Chromosomes then separate at the same velocity as the spindle poles in an anaphase B-like movement. We conclude that the majority of meiotic chromosome movement is caused by shortening of the spindle to bring poles in contact with the chromosomes, followed by separation of chromosome-bound poles by outward sliding

    Relocation remembered: Perspectives on senior transitions in the living environment

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    The experience of aging may necessitate transitions in living environments, either through adaptations to current residences or relocations to more supportive environments. For over a half century, the study of these transitions has informed the work of researchers, health and mental health providers, policymakers, and municipal planners. In the 1970s and ā€˜80s, knowledge about these transitions advanced through Lawton & Nahemowā€™s ecological theory of competence and environmental press, Wisemanā€™s behavioral model of relocation decision-making, and Litwak & Longinoā€™s developmental perspective on senior migrations. This paper revisits influential theoretical frameworks which contribute to our understanding of senior transitions in living environments. These seminal works are shown to inform recent studies of relocation and gerontology. This paper concludes with a call for a view on housing transitions that reflects the contemporary context

    Improving Patient Pre-screening for Clinical Trials: Assisting Physicians with Large Language Models

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    Physicians considering clinical trials for their patients are met with the laborious process of checking many text based eligibility criteria. Large Language Models (LLMs) have shown to perform well for clinical information extraction and clinical reasoning, including medical tests, but not yet in real-world scenarios. This paper investigates the use of InstructGPT to assist physicians in determining eligibility for clinical trials based on a patient's summarised medical profile. Using a prompting strategy combining one-shot, selection-inference and chain-of-thought techniques, we investigate the performance of LLMs on 10 synthetically created patient profiles. Performance is evaluated at four levels: ability to identify screenable eligibility criteria from a trial given a medical profile; ability to classify for each individual criterion whether the patient qualifies; the overall classification whether a patient is eligible for a clinical trial and the percentage of criteria to be screened by physician. We evaluated against 146 clinical trials and a total of 4,135 eligibility criteria. The LLM was able to correctly identify the screenability of 72% (2,994/4,135) of the criteria. Additionally, 72% (341/471) of the screenable criteria were evaluated correctly. The resulting trial level classification as eligible or ineligible resulted in a recall of 0.5. By leveraging LLMs with a physician-in-the-loop, a recall of 1.0 and precision of 0.71 on clinical trial level can be achieved while reducing the amount of criteria to be checked by an estimated 90%. LLMs can be used to assist physicians with pre-screening of patients for clinical trials. By forcing instruction-tuned LLMs to produce chain-of-thought responses, the reasoning can be made transparent to and the decision process becomes amenable by physicians, thereby making such a system feasible for use in real-world scenarios.Comment: 11 pages, 4 tables, 2 figure

    Pursuing the Longevity Dividend

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    The aging of humanity is about to experience a radical change as the demographic transformation to an older world is approaching its final stage. In recent decades, scientists have learned enough about the biological aging processes that many believe it will become possible to slow aging in humans. We contend that the social, economic, and health benefits that would result from such advances may be thought of as ā€œlongevity dividends,ā€ and that they should be aggressively pursued as the new approach to health promotion and disease prevention in the 21st century. The time has arrived for governments and national and international healthcare organizations to make research into healthy aging a major research priority.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/75679/1/annals.1396.050.pd

    Versatile transporter apparatus for experiments with optically trapped Bose-Einstein condensates

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    We describe a versatile and simple scheme for producing magnetically and optically-trapped Rb-87 Bose-Einstein condensates, based on a moving-coil transporter apparatus. The apparatus features a TOP trap that incorporates the movable quadrupole coils used for magneto-optical trapping and long-distance magnetic transport of atomic clouds. As a stand-alone device, this trap allows for the stable production of condensates containing up to one million atoms. In combination with an optical dipole trap, the TOP trap acts as a funnel for efficient loading, after which the quadrupole coils can be retracted, thereby maximizing optical access. The robustness of this scheme is illustrated by realizing the superfluid-to-Mott insulator transition in a three-dimensional optical lattice

    Priority Setting for Pandemic Influenza: An Analysis of National Preparedness Plans

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    The authors provide a targeted review of national pandemic influenza plans from the developed and developing world, describing national variations in prioritization of vaccines and antiviral medications

    ā€˜Pressure to play?ā€™ A sociological analysis of professional football managersā€™ behaviour towards injured players

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    This is an Accepted Manuscript of an article published by Taylor & Francis in Soccer and Society on 05/05/2017, available online: doi http://dx.doi.org/10.1080/14660970.2017.1321540Drawing upon figurational sociology, this paper examines professional football managersā€™ attitudes towards injured players. Following interviews with 10 managers, as with previous research, we found that managers have an expectancy that players are rarely fully fit. Players were stigmatised when they were seemingly unwilling to play when a manager encouraged them to. However, we also found that many managers shaped, in part, by their habitus formed from their own experiences as a player, showed greater empathy towards injured players. Many claimed they would not risk the long-term health of players, although at times, managers at the lower levels felt more constrained to take certain risks. We argue this is an unintended outcome of the increasing pressures on managers to succeed with smaller squads. The increasing emphasis and reliance on ā€˜sport scienceā€™ enabled managers at the higher levels to have a more supportive approach to managing injuries not previously identified in existing literature
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