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Marine Dupuit Audrey Boscaro Alban Bonnet Patrice Bouillon Pereira Bruno Claire Morel Mélanie Rance Nathalie Boisseau 《Scandinavian journal of medicine & science in sports》2020,30(12):2352-2363
This pilot study compared the effects of acute high-intensity intermittent exercise (HIIE) and moderate-intensity continuous exercise (MICE) on post-exercise VO2, fat utilization, and 24-hours energy balance to understand the mechanism of higher fat mass reduction observed after high-intensity interval training in post-menopausal women with overweight/obesity. 12 fasted women (59.5 ± 5.8 years; BMI: 28.9 ± 3.9 kg·m−2) completed three isoenergetic cycling exercise sessions in a counterbalanced, randomized order: (a) MICE [35 minutes at 60%-65% of peak heart rate, HRmax], (b) HIIE 1 [60 × (8-s cycling-12-s recovery) at 80%-90% of HRmax], and (c) HIIE 2 [10 × 1min at 80%-90% of HRmax − 1-min recovery]. Then, VO2 and fat utilization measured at rest and during the 2 hours post-exercise, enjoyment, perceived exertion, and appetite recorded during the session and energy intake (EI) and energy expenditure (EE) assessed over the next 24 hours were compared for the three modalities. Overall, fat utilization increased after exercise. No modality effect or time-modality interaction was observed concerning VO2 and fat oxidation rate during the 2 hours post-exercise. The two exercise modalities did not induce specific EI and EE adaptations, but perceived appetite scores at 1 hour post-exercise were lower after HIIE 1 and HIIE 2 than MICE. Perceived exertion was higher during HIIE 1 and HIIE 2 than MICE, but enjoyment did not differ among modalities. The acute HIIE responses did not allow explaining the greater fat mass loss observed after regular high-intensity interval training in post-menopausal women with overweight/obesity. More studies are needed to understand the mechanisms involved in such adaptations. 相似文献
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Séverine Bouttefroy Sandrine Meunier Vanessa Milien Mohamed Boucekine Pierre Chamouni Dominique Desprez Annie Harroche Audrey Hochart Marie Françoise Thiercelin-Legrand Bénédicte Wibaut Hervé Chambost Lucia Rugeri the CoDeC study group 《British journal of haematology》2020,188(2):317-320
This FranceCoag network study assessed 33 patients with congenital factor XIII (FXIII) deficiency presenting FXIII levels <10 iu/dl. Diagnosis was based on abnormal bleeding in 29 patients, a positive family history in 2, recurrent miscarriages in 1 and was fortuitous in 1. Eighteen patients (62·1%) presented life-threatening umbilical or intracranial haemorrhages (ICH). Seven of the 15 patients who experienced ICH were diagnosed but untreated, including 3 with secondary neurological sequelae. All pregnancies without prophylaxis (26/26) led to miscarriages versus 3/16 with prophylaxis. In patients exhibiting FXIII levels <10 iu/dl, prophylaxis could be discussed at diagnosis and at pregnancy. Further controlled prospective studies are needed. 相似文献
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Amy Wrzesniewski Barry Schwartz Xiangyu Cong Michael Kane Audrey Omar Thomas Kolditz 《Proceedings of the National Academy of Sciences of the United States of America》2014,111(30):10990-10995
Although people often assume that multiple motives for doing something will be more powerful and effective than a single motive, research suggests that different types of motives for the same action sometimes compete. More specifically, research suggests that instrumental motives, which are extrinsic to the activities at hand, can weaken internal motives, which are intrinsic to the activities at hand. We tested whether holding both instrumental and internal motives yields negative outcomes in a field context in which various motives occur naturally and long-term educational and career outcomes are at stake. We assessed the impact of the motives of over 10,000 West Point cadets over the period of a decade on whether they would become commissioned officers, extend their officer service beyond the minimum required period, and be selected for early career promotions. For each outcome, motivation internal to military service itself predicted positive outcomes; a relationship that was negatively affected when instrumental motives were also in evidence. These results suggest that holding multiple motives damages persistence and performance in educational and occupational contexts over long periods of time.Philosophers and psychologists have long distinguished among various types of motives to engage in particular activities. Some motives are internal or intrinsic to the activities themselves. The artist is motivated to create a great painting. The scientist is motivated to produce a major discovery. The gardener is motivated to grow a bountiful garden. In each case, the desired consequence matters; the artist, the scientist, and the gardener are not just dabbling. In each case, the activities leading to that consequence may involve hardship and struggle. And in each case, the desired outcome is intimately, intrinsically connected to the activity itself. The artist will not hire someone else to make the painting, nor will the gardener hire someone else to create a beautiful garden. In contrast to these kinds of internal motives, people are often guided by what might be called instrumental motives, where the relation between the motive and the activity is largely arbitrary (i.e., the motive bears no intrinsic relation to the activity itself). The scientist may want to earn a good salary, to get promoted, and to win awards. Whereas there are many paths to high salaries, promotions, and recognition, there is only one path to scientific discovery—doing science.Researchers have studied the relation between what we are calling “internal” and “instrumental” motives for more than 40 y. Typically, past research has designated these different types of motives as “intrinsic” and “extrinsic” (1). However, there is an ambiguity to the terms “intrinsic” and “extrinsic” in that they might refer to the actor (e.g., “he is intrinsically motivated”) or to the task (e.g., “drawing is an intrinsically motivated activity”). In addition, the term “intrinsic motivation” often conveys the idea that the activity in question is pleasant or fun (2). We prefer the terms “internal” and “instrumental” to make clearer that the relation being described is between the activity (not the person) and the motive, and also to make clear that internally motivated activities need not be undertaken for the inherent pleasure they bring (2, 3).What happens to the performance of demanding, effortful activities when internal and instrumental motives are combined? Logic would suggest that if you have one reason for doing something, having two or more reasons to do the same thing would be even better, rendering motivation more tenacious, follow-through stronger, and outcomes better. Schools and workplaces are full of systems that attempt to tap people’s internal motives to act (e.g., because engaging in the activity is the moral, interesting, or meaningful thing to do), while also providing rewards intended to spark instrumental motives to pursue the same acts (e.g., grades, bonuses, promotions, and so forth). Tapping internal motives and the instrumental motives assumed to result from rewards seems to be a foolproof way to engage the full spectrum of motivational levers that lead people to act. However, in a direct challenge to this assumption, social science research suggests that far from boosting motivation, holding instrumental motives can undermine whatever internal motives may have been operating, leading to drops in overall motivation, persistence, and performance (4–6). In short, this work suggests that salient instrumental incentives trigger instrumental motives, acting to undermine motivation that would otherwise be based in the value and reward of doing the activity or engaging in the act for the sake of objectives that are intimately connected to the act itself. This effect, labeled the “motivational crowding out effect” by economists (7) and the “overjustification effect” by psychologists (6), has been demonstrated across a range of experimental contexts (4). In the present study, rather than focusing on the impact of rewards on motives, we assess motives that already exist to understand their interactive effects on a series of long-term outcomes.The general structure of this body of research consists of laboratory and field experiments in which internal motivation is either established or assumed, followed by the introduction of instrumental rewards or inducements to an experimental group, and the comparison of outcomes of this group and a control group. The robustness of this effect has been generally accepted [but is still the subject of debate (6, 8, 9)]; indeed, recent research has found a possible neural basis for the “undermining effect” of instrumental rewards on internal motivation (10).Although it is possible to demonstrate the negative impact of instrumental rewards on activity-specific motivation, existing research typically introduces instrumental rewards as exogenous “shocks” to the system. However, in the real world, rather than suddenly being presented with rewards for actions in which they were already engaging, individuals carry an assortment of motives into any course of action they pursue: a mixture of activity-specific and instrumental motives in various combinations and at varying strengths (11). Whereas the typical experimental paradigm has demonstrated the relationship between internal and instrumental motivation in controlled settings through the introduction of instrumental rewards, longitudinal field research on the relative and interactive impact of various kinds and levels of motives on meaningful outcomes over time has been relatively lacking. Furthermore, examining the impact of the set and strength of motives that propel people to launch a course of action—joining the military, entering a university, becoming a volunteer—on the outcomes they later experience provides a test of naturally co-occurring motives on behavior. Additionally, as we will demonstrate, tests of the impact of different kinds of motives on outcomes occurring in real-world contexts need not depend on the introduction and withdrawal of instrumental rewards (as in experimental studies), but instead on the measurement of the strength of various kinds of motives that launched the course of action from the start.Prior work, mostly led by Deci and Ryan (2, 3), has demonstrated the ample benefits of intrinsic motivation or, at the very least, extrinsic motivation that has been internalized (what they call “autonomous motivation” in contrast to “controlled motivation,” which reflects compliance with others’ desires or external regulations), for well-being and a host of outcomes in education and health contexts. This research has treated motivation as a property of self-determination and has had a powerful impact on how social scientists understand and study motivation in a variety of contexts. However, in three important ways, our work takes a different approach to the impact of motives on outcomes, one that complements Deci and Ryan’s seminal research. First, although their approach to motivation considers whether motivation is intrinsic or extrinsic to the self (e.g., “I’m doing this because it’s natural to me” vs. “because I’ll feel badly if I don’t/others will criticize me if I don’t”) (3), our focus is on whether the motives people hold are internal or external to the activity (e.g., the scientist who pursues science to produce a discovery vs. to earn a salary or win awards). This distinction matters, because the theory of motivation presented by Deci and Ryan concerns identity, or how much of one’s motivation emanates from one’s psychological needs and sense of self (1) as opposed to other forces.Second, Deci and Ryan reserve “intrinsic” motivation as a label for only those activities that are undertaken for the inherent satisfaction they bring to the self, free from influence of what one’s parents, teachers, managers, or others think should be done or what one feels one should do (what they call “controlled motivation”), even if those reasons become somewhat or fully internalized (what they call “autonomous motivation”). Although this disqualifies most activities from ever being truly intrinsically motivated, “internal” motivation represents a broader category, one that we use here. It focuses on the relation between the outcomes pursued and the activity itself, rather than on relations between the activity and one’s self-definition or values (3).Furthermore, the outcomes that are assessed in experimental studies in this realm typically occur over a period of minutes, hours, or weeks rather than longer lengths of time, as occur in actual educational or workplace settings. Specifically, the ability of instrumental motives to effectively undermine the positive influence of internal motives on engagement in a course of action has not been demonstrated in a real-world context in which the outcomes have the potential to shape individual education and career trajectories and, more broadly, to shape public institutions. Even less is known about the impact of holding additional types of motives at varying levels of strength in these realms.There is some research that may provide clues. Researchers have reported the negative impact of holding multiple motives on individuals’ experience of a course of action they have voluntarily undertaken, demonstrating that holding multiple motives yields more stress and less satisfaction with the activity at hand (12). Other research in educational contexts that has differentiated between autonomous and controlled motivation (3) suggests that autonomous motivation predicts stronger persistence and better performance (13, 14), whereas controlled motivation predicts lower engagement and performance (15, 16). Furthermore, students experiencing high levels of both autonomous and controlled motivation have lower GPAs and procrastinate more than those with high levels of autonomous motivation and low levels of controlled motivation (17). Similarly, evidence from workplaces suggests that employees experiencing high levels of both autonomous and controlled motivation are poorer performers, even when their levels of initiative are high (18). Although these studies focus on the relationship between motivation inherent in the individual rather than for the activity at hand, the pattern is instructive: motivation that stems from sources external to the self undermines key outcomes.Clarifying the relation between different types of motives is of great practical significance. Whether called instrumental, controlled, or extrinsic (2, 3), some level of motivation from sources external to the activity itself is likely to occur in anyone undertaking a paid activity, which includes essentially every working adult. Because most people must work to make a living, instrumental consequences are ever present, and instrumental motives are likely present; thus, understanding the ways in which the strength of these motives vary and interact with motives internal to the activity is essential if we are to create work environments in which people work effectively and energetically.In the present study, we hypothesized that having strong internally based motives for undertaking a course of action will be associated with stronger persistence and better performance, but when these internally based motives are accompanied by strong instrumentally based motives, outcomes will be worse across a range of indicators of persistence and performance. We tested our hypotheses with data drawn from nine classes of West Point cadets at the start of their education, linking the strength of their various motives for attending West Point with outcomes that reflect their persistence and quality as military personnel between 4 and 14 y later. Although others have established the importance of grit for making it through West Point (19), the impact of cadets’ motives on this and later career outcomes is not yet understood.Specifically, we conducted analyses of data drawn from 11,320 cadets from nine consecutive entering classes of West Point cadets (the classes of 1997–2006). Data from the class of 2003 were dropped, as the survey instrument used that year used response categories that did not align with the questions for the items pertaining to cadets’ motives for attending West Point. We assessed the impact of cadets’ motives for attending West Point on the likelihood that they would successfully complete their studies and become commissioned officers, remain military officers beyond the mandatory 5-y period of service required following graduation, and be selected for consideration for early promotion during their 5 y of mandatory service. 相似文献
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Bani Tamraz Lori Reisner Audrey L. French Samuel T. King Margaret A. Fischl Igho Ofotokun Angela Kashuba Joel Milam Kerry Murphy Michael Augenbraun Chenglong Liu Patrick R. Finley Bradley Aouizerat Jennifer Cocohoba Stephen Gange Peter Bacchetti Ruth M. Greenblatt 《Pharmacotherapy》2019,39(9):899-911
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Audrey E Kaufman Sonum Naidu Sarayu Ramachandran Dalia S Kaufman Zahi A Fayad Venkatesh Mani 《World journal of radiology》2020,12(8):142-155
The purpose of this study is to review the published literature for the range of radiographic findings present in patients suffering from coronavirus disease 2019 infection. This novel corona virus is currently the cause of a worldwide pandemic. Pulmonary symptoms and signs dominate the clinical picture and radiologists are called upon to evaluate chest radiographs (CXR) and computed tomography (CT) images to assess for infiltrates and to define their extent, distribution and progression. Multiple studies attempt to characterize the disease course by looking at the timing of imaging relative to the onset of symptoms. In general, plain CXR show bilateral disease with a tendency toward the lung periphery and have an appearance most consistent with viral pneumonia. Chest CT images are most notable for showing bilateral and peripheral ground glass and consolidated opacities and are marked by an absence of concomitant pulmonary nodules, cavitation, adenopathy and pleural effusions. Published literature mentioning organ systems aside from pulmonary manifestations are relatively less common, yet present and are addressed in this review. Similarly, publications focusing on imaging modalities aside from CXR and chest CT are sparse in this evolving crisis and are likewise addressed in this review. The role of imaging is examined as it is currently being debated in the medical community, which is not at all surprising considering the highly infectious nature of Severe Acute Respiratory Syndrome coronavirus 2. 相似文献
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