To estimate international and national temporal trends in the cardiorespiratory fitness (CRF) of children and adolescents and to examine relationships between temporal trends in CRF and temporal ...trends in broad socioeconomic and health-related indicators across countries.
Data were obtained from a systematic search of studies that explicitly reported 20 m shuttle run test (a validated measure of CRF) descriptive data on apparently healthy individuals aged 9-17 years. Following the estimation of relative peak oxygen uptake (mL/kg/min) as a measure of CRF, sample-weighted temporal trends were estimated at the country-sex-age level using best-fitting linear or polynomial regression models relating the year of testing to mean CRF. Poststratified population-weighted mean changes in absolute and per cent CRF were estimated. Pearson's correlations were used to describe the association between linear temporal trends in CRF and linear temporal trends in broad socioeconomic and health-related indicators.
Temporal trends were estimated from 965 264 children and adolescents from 19 high-income and upper middle-income countries between 1981 and 2014, using data from 137 studies. Collectively, there was a moderate decline in CRF of 3.3 mL/kg/min (95% CI -3.5 to -3.1), equivalent to a decline of 7.3% (95% CI -7.8% to -6.7%) over the 33-year time period. This international decline diminished with each decade and stabilised near zero around 2000. The decline was larger for boys than girls and was similar for children and adolescents. Trends also differed in magnitude and direction between countries, with most showing declines. There was a strong negative association between country-specific trends in income inequality (Gini index) and trends in CRF across 18 countries; meaning, countries approaching income equality had more favourable trends in CRF.
There has been a substantial decline in CRF since 1981, which is suggestive of a meaningful decline in population health. However, the international trend in CRF has not followed the anticipated trajectory, diminishing and stabilising with negligible change since 2000. CRF data are needed from children in low-income and middle-income countries to more confidently determine true international trends and determine whether temporal trends are similar to those observed in high-income and upper middle-income countries.
Despite the erosion of microsurgical case volume because of advances in endovascular and radiosurgical therapies, indications remain for open resection of pathology and highly technical vascular ...repairs. Treatment risk, efficacy, and durability make open microsurgery a preferred option for cerebral cavernous malformations, arteriovenous malformations (AVMs), and many aneurysms. In this paper, a 21-year experience with 7348 cases was reviewed to identify trends in microsurgical management. Brainstem cavernous malformations (227 cases), once considered inoperable and managed conservatively, are now resected in increasing numbers through elegant skull base approaches and newly defined safe entry zones, demonstrating that microsurgical techniques can be applied in ways that generate entirely new areas of practice. Despite excellent results with microsurgery for low-grade AVMs, brain AVM management (836 cases) is being challenged by endovascular embolization and radiosurgery, as well as by randomized trials that show superior results with medical management. Reviews of ARUBA-eligible AVM patients treated at high-volume centers have demonstrated that open microsurgery with AVM resection is still better than many new techniques and less invasive approaches that are occlusive or obliterative. Although the volume of open aneurysm surgery is declining (4479 cases), complex aneurysms still require open microsurgery, often with bypass techniques. Intracranial arterial reconstructions with reimplantations, reanastomoses, in situ bypasses, and intracranial interpositional bypasses (third-generation bypasses) augment conventional extracranial-intracranial techniques (first- and second-generation bypasses) and generate innovative bypasses in deep locations, such as for anterior inferior cerebellar artery aneurysms. When conventional combinations of anastomoses and suturing techniques are reshuffled, a fourth generation of bypasses results, with eight new types of bypasses. Type 4A bypasses use in situ suturing techniques within the conventional anastomosis, whereas type 4B bypasses maintain the basic construct of reimplantations or reanastomoses but use an unconventional anastomosis. Bypass surgery (605 cases) demonstrates that open microsurgery will continue to evolve. The best neurosurgeons will be needed to tackle the complex lesions that cannot be managed with other modalities. Becoming an open vascular neurosurgeon will be intensely competitive. The microvascular practice of the future will require subspecialization, collaborative team effort, an academic medical center, regional prominence, and a large catchment population, as well as a health system that funnels patients from hospital networks outside the region. Dexterity and meticulous application of microsurgical technique will remain the fundamental skills of the open vascular neurosurgeon.
A
bstract
We present calculations of Higgs boson production via gluon-gluon fusion in association with one or two additional jets at next-to-leading order in QCD. The calculation of
H
+jet is exact ...in the treatment of the top-quark mass, whereas for the
H
+2 jets calculation the two-loop virtual amplitudes are approximated via a reweighting with leading-order mass effects, while keeping all top-quark mass effects in the real radiation contributions. For
H
+jet production, this study extends a previous calculation, revealing an error in the previous results. For total and differential cross sections, we present new results and compare the QCD corrections with the infinite top-mass limit, for which we find a strikingly good agreement if all amplitudes are rescaled by the leading-order mass dependence.
Achieving the goal of sustainability requires understanding and management of unprecedented and interconnected challenges. A transdisciplinary approach is a key component of sustainability science. ...However, there are considerable barriers to implementing transdisciplinary projects. We undertake a mixed quantitative and qualitative analysis of peer-reviewed sustainability science studies where the transdisciplinary approach has been applied. We assess the growth and scientific impact of transdisciplinary sustainability research, the methods used and how three key characteristics of transdisciplinarity research—process phases, knowledge types and the intensity of involvement of practitioners—are implemented. While transdisciplinary research is growing there is no common glossary, no focused communication platform and no commonly shared research framework. Transdisciplinary research utilizes a broad, but not clearly defined, set of methods for knowledge production. While the intensity of practitioner involvement varied within the case studies analyzed, very few realized empowerment. Based on our review of transdisciplinary case study papers we conclude that transdisciplinary research must be clearly framed, including the use of a common terminology and the development of a broad suite of appropriate methods. Despite the challenges highlighted here, science needs to move beyond classical disciplinary approaches and should consider interdisciplinary work that engages with practitioners to achieve sustainable transitions.
•We reviewed peer-reviewed publications of transdisciplinary sustainability science.•Advocated ‘best practice’ is not followed in applied transdisciplinary literature.•Methods are independent of the transdisciplinary process phases and knowledge types.•Scientists and practitioners exchange knowledge but stakeholder empowerment is rare.•Scientists and practitioners must take responsibility to tackle real world problems.
Replacing conventional dialkylamino substituents with a three-membered aziridine ring in naphthalimide leads to significantly enhanced brightness and photostability by effectively suppressing twisted ...intramolecular charge transfer formation. This replacement is generalizable in other chemical families of fluorophores, such as coumarin, phthalimide, and nitrobenzoxadiazole dyes. In highly polar fluorophores, we show that aziridinyl dyes even outperform their azetidinyl analogues in aqueous solution. We also proposed one simple mechanism that can explain the vulnerability of quantum yield to hydrogen bond interactions in protonic solvents in various fluorophore families. Such knowledge is a critical step toward developing high-performance fluorophores for advanced fluorescence imaging.
Introduction La sécrétion physiologique d'insuline nécessite des couplages entre les cellules β des îlots pancréatiques. Décrire ces couplages et leurs dérégulations représente un défi technologique ...requérant une haute résolution temporelle sur le long terme. Le multielectrode array (MEA) est une approche électrophysiologique non-invasive permettant cela à 10'000 mesures/seconde. Avec cette technique, nous avions découvert les potentiels lents (PLs) qui sont les marqueurs électriques des couplages intra-îlot. L'objectif ici est de comprendre la genèse de ces signaux et de décrire leur rôle dans la cinétique des réponses au glucose. Matériels et Méthodes Les PLs des îlots de souris et humains ont été mesurés sur des MEAs à 60 microélectrodes extracellulaires en titane. Pour suivre en même temps le potentiel transmembranaire des cellules, une technique électrophysiologique intracellulaire a été employée (le sharp) consistant à introduire délicatement dans leur cytoplasme de fines électrodes en verre (Ø < 0,5 μm). Résultats Les enregistrements MEAs confirment le rôle physiologique des PLs puisque leurs fréquences augmentent avec le glucose, l'arginine et le GLP-1 ; alors que l'adrénaline, hormone hyperglycémiante, les inhibe (IC50 11,7 nm). La combinaison MEA/sharp montre que ces événements multicellulaires correspondent à la sommation de dépolarisations intracellulaires générées de manière synchrone par les cellules β d'un même cluster/ îlot. De plus, le suivi temporo-spatial de la propagation des PLs sur MEAs indique l'existence de pacemakers. Pour la première fois également nous décrivons des changements de couplages électriques au cours de la réponse au glucose. La cinétique de ces changements est biphasique et pulsatile montrant le lien direct avec la dynamique sécrétoire. En effet, dans la première phase la fréquence des PLs est maximale et leur amplitude augmente progressivement, alors que dans la seconde leur amplitude reste maximale et leur fréquence oscille autour d'un plateau (période ~5 min). Conclusions Nos résultats indiquent que le développement temporo-spatial des potentiels lents commande la dynamique sécrétoire des îlots. Par la suite ceci permettra aussi de mettre au point des biocapteurs pour le contrôle/qualité avant greffe des îlots et des cellules souches différenciées.
To develop sex-specific and age-specific international norms for the 20 m shuttle run test (20mSRT) in children and youth (aged 9-17 years), and to estimate the prevalence meeting the FITNESSGRAM ...criterion-referenced standards for healthy cardiorespiratory endurance (CRE).
A systematic review was undertaken to identify papers explicitly reporting descriptive 20mSRT (with 1 min stages) data on children and youth since 1981. Data were included on apparently healthy (free from known disease/injury) 9-17 years old. Following standardisation to a common metric and for protocol differences, pseudo data were generated using Monte Carlo simulation, with population-weighted sex-specific and age-specific normative centiles generated using the Lambda Mu and Sigma (LMS) method. Sex-related and age-related differences were expressed as per cent and standardised differences in means. The prevalence with healthy CRE was estimated using the sex-specific and age-specific FITNESSGRAM criterion-referenced standards for Formula: see text.
Norms were displayed as tabulated centiles and as smoothed centile curves for the 20mSRT using 4 common metrics (speed at the last completed stage, completed stages/minutes, laps and relative Formula: see text). The final data set included 1 142 026 children and youth from 50 countries, extracted from 177 studies. Boys consistently outperformed girls at each age group (mean difference±95% CI: 0.86±0.28 km/h or 0.79±0.20 standardised units), with the magnitude of age-related increase larger for boys than for girls. A higher proportion of boys (mean±95% CI: 67±14%) had healthy CRE than girls (mean±95% CI: 54±17%), with the prevalence of healthy CRE decreasing systematically with age.
This study provides the most comprehensive and up-to-date set of international sex-specific and age-specific 20mSRT norms for children and youth, which have utility for health and fitness screening, profiling, monitoring and surveillance.
The adult mammalian cerebellar cortex is generally assumed to have a uniform cytoarchitecture. Differences in cerebellar function are thought to arise primarily through distinct patterns of input and ...output connectivity rather than as a result of variations in cortical microcircuitry. However, evidence from anatomical, physiological and genetic studies is increasingly challenging this orthodoxy, and there are now various lines of evidence indicating that the cerebellar cortex is not uniform. Here, we develop the hypothesis that regional differences in properties of cerebellar cortical microcircuits lead to important differences in information processing.
Celotno besedilo
Dostopno za:
DOBA, IJS, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SBMB, UILJ, UKNU, UL, UM, UPUK
PDF
