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1.
medRxiv ; 2024 Apr 26.
Article in English | MEDLINE | ID: mdl-38712264

ABSTRACT

As societies age, policy makers need tools to understand how demographic aging will affect population health and to develop programs to increase healthspan. The current metrics used for policy analysis do not distinguish differences caused by early-life factors, such as prenatal care and nutrition, from those caused by ongoing changes in people's bodies due to aging. Here we introduce an adapted Pace of Aging method designed to quantify differences between individuals and populations in the speed of aging-related health declines. The adapted Pace of Aging method, implemented in data from N=13,626 older adults in the US Health and Retirement Study, integrates longitudinal data on blood biomarkers, physical measurements, and functional tests. It reveals stark differences in rates of aging between population subgroups and demonstrates strong and consistent prospective associations with incident morbidity, disability, and mortality. Pace of Aging can advance the population science of healthy longevity.

2.
J Nutr Health Aging ; 27(10): 806-807, 2023.
Article in English | MEDLINE | ID: mdl-37960902
3.
Phys Rev Lett ; 130(26): 265101, 2023 Jun 30.
Article in English | MEDLINE | ID: mdl-37450828

ABSTRACT

The propagation and energy coupling of intense laser beams in plasmas are critical issues in inertial confinement fusion. Applying magnetic fields to such a setup has been shown to enhance fuel confinement and heating. Here we report on experimental measurements demonstrating improved transmission and increased smoothing of a high-power laser beam propagating in a magnetized underdense plasma. We also measure enhanced backscattering, which our kinetic simulations show is due to magnetic confinement of hot electrons, thus leading to reduced target preheating.


Subject(s)
Electrons , Heating , Heart Rate , Kinetics , Lasers
5.
Proc Biol Sci ; 290(1996): 20222524, 2023 04 12.
Article in English | MEDLINE | ID: mdl-37015271

ABSTRACT

Studies of the fossil record can inform our understanding of not only the causes of mass extinctions, but also their effects on biodiversity, ecology and evolution. Here, we examine regional-scale ecological changes resulting from a Late Devonian mass extinction event using brachiopod fossil assemblages from the Appalachian Basin. About half of the species went extinct, but were largely replaced by new immigrant taxa. Both before and after the extinction, the primary gradient in faunal composition was correlated with onshore-offshore position, with a second gradient attributed to frequency of disturbance. Survivors of the extinction displayed a strong degree of niche conservatism along these gradients. Despite these indicators of ecological stability, the pre- and post-extinction faunas were quite distinct at the order level, with atrypids and strophomenids largely replaced by productids, whose spiny shells may have provided greater resistance to disturbance and/or predation. Thus, extinction survivors persisted in similar ecological niches despite environmental perturbations and considerable change in the taxonomic and ecological composition of the regional species pool.


Subject(s)
Extinction, Biological , Invertebrates , Animals , Ecosystem , Fossils , Biodiversity , Biological Evolution
6.
Ageing Res Rev ; 73: 101537, 2022 01.
Article in English | MEDLINE | ID: mdl-34883201

ABSTRACT

Improvements in public health and health care have resulted in significant increases in lifespan globally, but also in a significant increase in chronic disease prevalence. This has led to a focus on healthy ageing bringing a shift from a pathology-centered to an intrinsic capacity and function-centered view. In parallel, the emerging field of geroscience has promoted the exploration of the biomolecular drivers of ageing towards a transverse vision by proposing an integrated set of molecular hallmarks. In this review, we propose to take a step further in this direction, highlighting a gerophysiological perspective that considers the notion of homeostasis/allostasis relating to robustness/fragility respectively. While robustness is associated with homeostasis achieved by an optimal structure/function relationship in all organs, successive repair processes occurring after daily injuries and infections result in accumulation of scar healing leading to progressive tissue degeneration, allostasis and frailty. Considering biological ageing as the accumulation of scarring at the level of the whole organism emphasizes three transverse and shared elements in the body - mesenchymal stroma cells/immunity/metabolism (SIM). This SIM tryptich drives tissue and organ fate to regulate the age-related evolution of body functions. It provides the basis of a gerophysiology perspective, possibly representing a better way to decipher healthy ageing, not only by defining a composite biomarker(s) but also by developing new preventive/curative strategies.


Subject(s)
Frailty , Healthy Aging , Aging , Geroscience , Humans , Longevity
7.
Sci Rep ; 11(1): 24366, 2021 12 21.
Article in English | MEDLINE | ID: mdl-34934059

ABSTRACT

The fossil record can illuminate factors that contribute to extinction risk during times of global environmental disturbance; for example, inferred thermal tolerance was an important predictor of extinction during several mass extinctions that corresponded with climate change. Additionally, members of geographically isolated biotas may face higher risk because they have less opportunity to migrate to suitable climate refugia during environmental disturbances. Here, we investigate how different types of risk intersect in the well-preserved brachiopod fauna of the Appalachian Foreland Basin during the two pulses of the Frasnian-Famennian mass extinction (Late Devonian, ~ 372 Ma). The selectivity of extinction is consistent with climate change (cooling) as a primary kill mechanism in this fauna. Overall, the extinction was mild relative to other regions, despite the many endemic species. However, vulnerable taxa went extinct more rapidly, during the first extinction pulse, such that the second pulse was insignificant. These results suggest that vulnerable taxa in geographically isolated biotas face heightened extinction risk at the initiation of environmental stress, but that taxa in other regions may eventually see elevated extinction risk if environmental stress repeats or intensifies.

8.
Rev Sci Instrum ; 92(10): 104710, 2021 Oct 01.
Article in English | MEDLINE | ID: mdl-34717401

ABSTRACT

In this paper, we describe a novel pulsed magnet, called foil coil, which can deliver a field transverse to the light propagation of more than 10 T over about 0.8 m operating without cryogenic equipment. It has been designed for linear magnetic birefringence measurements. We report on testing the coil and also show some physics data taken in vacuum during its commissioning in the framework of the Biréfringence Magnétique du Vide (BMV) apparatus, with special attention to noise induced by the pulse itself. Finally, we compare the preliminary results obtained here with data from the previous BMV coil.

9.
J Frailty Aging ; 10(4): 313-319, 2021.
Article in English | MEDLINE | ID: mdl-34549244

ABSTRACT

The find solutions for optimizing healthy aging and increase health span is one of the main challenges for our society. A novel healthcare model based on integration and a shift on research and care towards the maintenance of optimal functional levels are now seen as priorities by the WHO. To address this issue, an integrative global strategy mixing longitudinal and experimental cohorts with an innovative transverse understanding of physiological functioning is missing. While the current approach to the biology of aging is mainly focused on parenchymal cells, we propose that age-related loss of function is largely determined by three elements which constitute the general ground supporting the different specific parenchyma: i.e. the stroma, the immune system and metabolism. Such strategy that is implemented in INSPIRE projects can strongly help to find a composite biomarker capable of predicting changes in capacity across the life course with thresholds signalling frailty and care dependence.


Subject(s)
Frailty , Healthy Aging , Aging , Biomarkers , Humans
10.
Nat Commun ; 12(1): 762, 2021 Feb 03.
Article in English | MEDLINE | ID: mdl-33536408

ABSTRACT

The shaping of astrophysical outflows into bright, dense, and collimated jets due to magnetic pressure is here investigated using laboratory experiments. Here we look at the impact on jet collimation of a misalignment between the outflow, as it stems from the source, and the magnetic field. For small misalignments, a magnetic nozzle forms and redirects the outflow in a collimated jet. For growing misalignments, this nozzle becomes increasingly asymmetric, disrupting jet formation. Our results thus suggest outflow/magnetic field misalignment to be a plausible key process regulating jet collimation in a variety of objects from our Sun's outflows to extragalatic jets. Furthermore, they provide a possible interpretation for the observed structuring of astrophysical jets. Jet modulation could be interpreted as the signature of changes over time in the outflow/ambient field angle, and the change in the direction of the jet could be the signature of changes in the direction of the ambient field.

11.
J Frailty Aging ; 10(2): 103-109, 2021.
Article in English | MEDLINE | ID: mdl-33575698

ABSTRACT

INTRODUCTION: Limiting the number of dependent older people in coming years will be a major economic and human challenge. In response, the World Health Organization (WHO) has developed the «Integrated Care for Older People (ICOPE)¼ approach. The aim of the ICOPE program is to enable as many people as possible to age in good health. To reach this objective, the WHO proposes to follow the trajectory of an individual's intrinsic capacity, which is the composite of all their physical and mental capacities and comprised of multiple domains including mobility, cognition, vitality / nutrition, psychological state, vision, hearing. OBJECTIVE: The main objective of the INSPIRE ICOPE-CARE program is to implement, in clinical practice at a large scale, the WHO ICOPE program in the Occitania region, in France, to promote healthy aging and maintain the autonomy of seniors using digital medicine. METHOD: The target population is independent seniors aged 60 years and over. To follow this population, the 6 domains of intrinsic capacity are systematically monitored with pre-established tools proposed by WHO especially STEP 1 which has been adapted in digital form to make remote and large-scale monitoring possible. Two tools were developed: the ICOPE MONITOR, an application, and the BOTFRAIL, a conversational robot. Both are connected to the Gerontopole frailty database. STEP 1 is performed every 4-6 months by professionals or seniors themselves. If a deterioration in one or more domains of intrinsic capacity is identified, an alert is generated by an algorithm which allows health professionals to quickly intervene. The operational implementation of the INSPIRE ICOPE-CARE program in Occitania is done by the network of Territorial Teams of Aging and Prevention of Dependency (ETVPD) which have more than 2,200 members composed of professionals in the medical, medico-social and social sectors. Targeted actions have started to deploy the use of STEP 1 by healthcare professionals (physicians, nurses, pharmacists,…) or different institutions like French National old age insurance fund (CNAV), complementary pension funds (CEDIP), Departmental Council of Haute Garonne, etc. Perspective: The INSPIRE ICOPE-CARE program draws significantly on numeric tools, e-health and digital medicine to facilitate communication and coordination between professionals and seniors. It seeks to screen and monitor 200,000 older people in Occitania region within 3 to 5 years and promote preventive actions. The French Presidential Plan Grand Age aims to largely implement the WHO ICOPE program in France following the experience of the INSPIRE ICOPE-CARE program in Occitania.


Subject(s)
Cooperative Behavior , Delivery of Health Care, Integrated , Geriatrics , Program Development , World Health Organization , Aged , Aged, 80 and over , Delivery of Health Care, Integrated/organization & administration , France , Geriatrics/organization & administration , Humans , Middle Aged , World Health Organization/organization & administration
13.
Maturitas ; 141: 39-45, 2020 Nov.
Article in English | MEDLINE | ID: mdl-33036701

ABSTRACT

OBJECTIVES: To investigate the effect of omega-3 (ω-3) polyunsaturated fatty acid supplementation and a multidomain intervention (MI) (physical activity counselling, cognitive training and nutritional advice) among community-dwelling older adults on levels of intrinsic capacity (IC), a construct recently proposed by the World Health Organization. STUDY DESIGN: Secondary analysis from the factorial-design 3-year Multidomain Alzheimer Preventive Trial (MAPT) with 1445 subjects (64.2 % female, mean age 75.3 years, SD = 4.4) randomized to one group of MI plus ω-3 (800 mg docosahexaenoic acid and 225 mg eicosapentaenoic acid/day); MI plus placebo; ω-3 supplementation alone; or placebo alone. Data collection was held between 2008 and 2014. MAIN OUTCOME MEASURES: IC domains were examined with the Geriatric Depression Scale (psychological); Short Physical Performance Battery (mobility); Z-score combining four tests (cognitive function); and handgrip strength (vitality). All domains were combined into a composite IC Z-score. RESULTS: After 3 years, IC Z-score decreased among all groups when time was considered continuous (MI plus ω-3: -0.16, 95 %CI: -0.22 to -0.10; MI alone: -0.13, 95 %CI: -0.19 to -0.07; ω-3 alone: -0.19, 95 %CI: -0.25 to -0.10; placebo: -0.20, 95 %CI: -0.26 to -0.14; all p < 0.0001). There were no significant differences between groups. In a sensitivity analysis with categorical time, significant within-group declines were first identified at 24 months for all groups. CONCLUSIONS: This trial designed to improve cognitive function was unable to find effects of the intervention on the composite IC Z-score. Further investigations are needed, especially trials providing stronger interventions (such as exercise training and a controlled diet) and also embracing the sensorial domain of IC.


Subject(s)
Alzheimer Disease/prevention & control , Cognition/drug effects , Fatty Acids, Omega-3/therapeutic use , Aged , Aged, 80 and over , Dietary Supplements , Docosahexaenoic Acids , Eicosapentaenoic Acid/analogs & derivatives , Exercise , Fatty Acids, Omega-3/pharmacology , Female , Geriatric Assessment , Hand Strength , Healthy Lifestyle , Humans , Independent Living , Life Style , Longitudinal Studies , Male , Range of Motion, Articular/drug effects
14.
J Nutr Health Aging ; 24(7): 692-695, 2020.
Article in English | MEDLINE | ID: mdl-32744562

ABSTRACT

The SARS-CoV-2 infection is particularly associated with negative outcomes (i.e., serious disease, death) in frail older people, independently of where they live. Furthermore, the period of pandemic (with its lockdowns, social distancing, fragmentation of care…) has significantly changed the environment in which older people live. It is likely that, when the pandemic will be over, an acceleration of the aging process will be observed for many persons, independently of whether they have been infected or not by the SARS-CoV-2. The World report on ageing and health, published by the World Health Organization, proposes the concept of intrinsic capacity (i.e., the composite of all the physical and mental capacities of the individual) as central for healthy ageing. The routine assessment of biological age through constructs such as intrinsic capacity might have allowed a better understanding of the functional trajectories and vulnerabilities of the individual, even during a catastrophic event as the one we are currently living. In the present article, we describe how COVID-19 has affected the persons' intrinsic capacity, and how the wide adoption of the intrinsic capacity model may support the modernization of our systems and bring them closer to the individual.


Subject(s)
Aging/psychology , Betacoronavirus , Coronavirus Infections/epidemiology , Coronavirus Infections/virology , Healthy Aging , Pneumonia, Viral/epidemiology , Pneumonia, Viral/virology , Aged , Aged, 80 and over , COVID-19 , Humans , Pandemics , SARS-CoV-2 , Social Isolation
16.
Phys Rev Lett ; 123(20): 205001, 2019 Nov 15.
Article in English | MEDLINE | ID: mdl-31809120

ABSTRACT

Magnetized laser-produced plasmas are central to many novel laboratory astrophysics and inertial confinement fusion studies, as well as in industrial applications. Here we provide the first complete description of the three-dimensional dynamics of a laser-driven plasma plume expanding in a 20 T transverse magnetic field. The plasma is collimated by the magnetic field into a slender, rapidly elongating slab, whose plasma-vacuum interface is unstable to the growth of the "classical," fluidlike magnetized Rayleigh-Taylor instability.

17.
BJS Open ; 3(5): 704-712, 2019 10.
Article in English | MEDLINE | ID: mdl-31592089

ABSTRACT

Background: A workforce crisis exists in global surgery. One solution is task-shifting, the delegation of surgical tasks to non-physician clinicians or associate clinicians (ACs). Although several studies have shown that ACs have similar postoperative outcomes compared with physicians, little is known about their surgical training. This study aimed to characterize the surgical training and experience of ACs compared with medical officers (MOs) in Tanzania. Methods: All surgical care providers in Pwani Region, Tanzania, were surveyed. Participants reported demographic data, years of training, and procedures assisted and performed during training. They answered open-ended questions about training and post-training surgical experience. The median number of training cases for commonly performed procedures was compared by cadre using Wilcoxon rank sum and Student's t tests. The researchers performed modified content analysis of participants' answers to open-ended questions on training needs and experiences. Results: A total of 21 ACs and 12 MOs participated. ACs reported higher exposure than MOs to similar procedures before their first independent operation (median 40 versus 17 cases respectively; P = 0·031). There was no difference between ACs and MOs in total training surgical volume across common procedures (median 150 versus 171 cases; P = 0·995). Both groups reflected similarly upon their training. Each cadre relied on the other for support and teaching, but noted insufficient specialist supervision during training and independent practice. Conclusions: ACs report similar training and operative experience compared with their physician colleagues in Tanzania.


Antecedentes: La falta de cirujanos en determinadas áreas geográficas es flagrante. Una posible solución es el intercambio de tareas, es decir, la delegación de tareas quirúrgicas en personal sanitario no médico o en clínicos asociados (associate clinicians, AC). Si bien varios estudios han demostrado que los AC obtienen resultados postoperatorios similares a los de los médicos, hay poco información acerca de su entrenamiento quirúrgico. Este estudio tuvo como objetivo caracterizar la capacitación quirúrgica y la experiencia de los AC en comparación con los médicos titulados (medical officer, MO) en Tanzania. Métodos: En este estudio, se encuestaron todos los proveedores de atención quirúrgica de la Región de Pwani, Tanzania. Los participantes proporcionaron datos demográficos, años de entrenamiento y número y tipo de procedimientos realizados y a los que se había asistido durante el periodo de capacitación. Además, respondieron a preguntas abiertas sobre el entrenamiento y su experiencia quirúrgica posterior al entrenamiento. Se comparó la mediana del número de procedimientos más realizados por cada grupo mediante la suma de rangos de Wilcoxon y la prueba de la t de Student. Los investigadores realizaron un análisis del contenido de las respuestas a las preguntas abiertas sobre las necesidades y la experiencia durante la etapa de entrenamiento. Resultados: En el estudio participaron 21 ACs y 12 MOs. Los CA estuvieron expuestos a un mayor número procedimientos del mismo tipo antes de efectuar su primera operación de forma independiente en comparación con los OM (40 versus 17 casos, P = 0,031). No hubo diferencias en el volumen operatorio total de los procedimientos comunes entre los AC y los MO (150 versus 171 casos, P = 0,995). Las opiniones de los dos grupos sobre el entrenamiento fueron similares. Los dos grupos se dieron soporte entre ellos, pero quedó patente que la supervisión por parte de un especialista durante el entrenamiento y la práctica independiente era insuficiente. Conclusiones: En Tanzania, los asociados clínicos tienen entrenamientos y experiencias quirúrgicas similares a las de sus colegas médicos.


Subject(s)
General Surgery/education , Health Personnel/education , Physicians/statistics & numerical data , Preceptorship/statistics & numerical data , Surgical Procedures, Operative/education , Adult , Allied Health Personnel/education , Clinical Competence/statistics & numerical data , Education, Medical/methods , Evaluation Studies as Topic , Female , Health Personnel/statistics & numerical data , Health Workforce/organization & administration , Health Workforce/trends , Humans , Male , Middle Aged , Poverty/economics , Poverty/statistics & numerical data , Preceptorship/methods , Quality of Health Care , Retrospective Studies , Surgical Procedures, Operative/statistics & numerical data , Surveys and Questionnaires/statistics & numerical data , Tanzania/epidemiology
18.
Rev Sci Instrum ; 89(5): 053905, 2018 May.
Article in English | MEDLINE | ID: mdl-29864875

ABSTRACT

We present the first long-duration and high duty cycle 40-T pulsed-field cryomagnet addressed to single crystal neutron diffraction experiments at temperatures down to 2 K. The magnet produces a horizontal field in a bi-conical geometry, ±15° and ±30° upstream and downstream of the sample, respectively. Using a 1.15 MJ mobile generator, magnetic field pulses of 100 ms length are generated in the magnet, with a rise time of 23 ms and a repetition rate of 6-7 pulses per hour at 40 T. The setup was validated for neutron diffraction on the CEA-CRG three-axis spectrometer IN22 at the Institut Laue Langevin.

19.
Br J Surg ; 105(6): 719-727, 2018 05.
Article in English | MEDLINE | ID: mdl-29601087

ABSTRACT

BACKGROUND: Surgeons' non-technical skills are an important part of surgical performance and surgical education. The most widely adopted assessment tool is the Non-Technical Skills for Surgeons (NOTSS) behaviour rating system. Psychometric analysis of this tool to date has focused on inter-rater reliability and feasibility rather than validation. METHODS: NOTSS assessments were collected from two groups of consultant/attending surgeons in the UK and USA, who rated behaviours of the lead surgeon during a video-based simulated crisis scenario after either online or classroom instruction. The process of validation consisted of assessing construct validity, scale reliability and concurrent criterion validity, and undertaking a sensitivity analysis. Central to this was confirmatory factor analysis to evaluate the structure of the NOTSS taxonomy. RESULTS: Some 255 consultant surgeons participated in the study. The four-category NOTSS model was found to have robust construct validity evidence, and a superior fit compared with alternative models. Logistic regression and sensitivity analysis revealed that, after adjusting for technical skills, for every 1-point increase in NOTSS score of the lead surgeon, the odds of having a higher versus lower patient safety score was 2·29 times. The same pattern of results was obtained for a broad mix of surgical specialties (UK) as well as a single discipline (cardiothoracic, USA). CONCLUSION: The NOTSS tool can be applied in research and education settings to measure non-technical skills in a valid and efficient manner.


Subject(s)
Clinical Competence/standards , Surgeons/standards , Awareness , Clinical Competence/statistics & numerical data , Communication , Decision Making , Factor Analysis, Statistical , Humans , Leadership , Psychometrics , Reproducibility of Results , Surgeons/psychology , Surgeons/statistics & numerical data , Video Recording
20.
Rev Sci Instrum ; 88(7): 073102, 2017 Jul.
Article in English | MEDLINE | ID: mdl-28764544

ABSTRACT

We present a new technique to measure pulsed magnetic fields based on the use of rubidium in gas phase as a metrological standard. We have therefore developed an instrument based on laser inducing transitions at about 780 nm (D2 line) in rubidium gas contained in a mini-cell of 3 mm × 3 mm cross section. To be able to insert such a cell in a standard high-field pulsed magnet, we have developed a fibred probe kept at a fixed temperature. Transition frequencies for both the π (light polarization parallel to the magnetic field) and σ (light polarization perpendicular to the magnetic field) configurations are measured by a commercial wavemeter. One innovation of our sensor is that in addition to the usual monitoring of the light transmitted by the Rb cell, we also monitor the fluorescence emission of the gas sample from a volume of 0.13 mm3. Our sensor has been tested up to about 58 T.

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