59 research outputs found
A dynamical mass map of the Fornax cluster
Galaxienhaufen sind die größten gravitativ gebundenen Objekte im Universum. Sie bieten die Möglichkeit, die Verteilung der baryonischen und dunklen Materie auf einer großen physikalischen Skala zu untersuchen. Der Fornax-Galaxienhaufen ist einer der nächsten und dichtesten Galaxienhaufen. Frühere photometrische Untersuchungen des Fornax-Galaxienhaufens haben das Vorhandensein stellarer und gezeitenbedingter Strukturen im Kern und in den Intra-Cluster-Regionen gezeigt. Untersuchungen der Kugelsternhaufenpopulationen (GCs) in Fornax haben eine Überdichte von GCs aufgewiesen, die mehrere zentrale Haufengalaxien miteinander verbindet. GCs sind helle und kompakte Quellen, die als diskrete kinematische Tracer verwendet werden können, um die stellare Population und die Massenverteilung in den Außenbezirken der Galaxien zu untersuchen, wo die Feldsterne zu schwach sind, um direkt beobachtet zu werden. Ziel dieser Arbeit ist es, den Massenaufbau des Fornax-Galaxienhaufens mit Hilfe seiner GC-Systeme zu untersuchen.
Das Verständnis des Ursprungs und des kinematischen Verhaltens der GCs innerhalb von Fornax ist entscheidend, um den Masseaufbau des Galaxienhaufens zu verstehen. Arbeiten zur dynamischen Massenmodellierung von Galaxienhaufen haben gezeigt, dass die Vernachlässigung von Substrukturen, die durch Akkretions- und Fusionsereignisse entstehen, Auswirkungen auf die Massenschätzung von Haufen haben kann. Der Fornax-Haufen bietet eine hervorragende Gelegenheit, die Rolle der Substrukturen bei der Massenmodellierung zu untersuchen. In dieser Arbeit habe ich die spektroskopischen Daten des Visible Multi-Object Spectrograph am Very Large Telescope (VLT/VIMOS) aus der spektroskopischen Durchmusterung des Fornax-Haufens am VLT (FVSS) verwendet, die einen Quadratgrad um die zentrale massereiche Galaxie NGC 1399 abdeckt.
Ich habe VIMOS-FVSS-Daten zur kinematischen Charakterisierung der photometrisch entdeckten GC Kandidaten verwendet. Mit einer sorgfältigen Analyse dieser Daten detektiere ich insgesamt 777 GCs, was fast einer Verdoppelung der bereits entdeckten GCs entspricht, wobei ich denselben Datensatz wie zuvor verwendet habe. In Kombination mit früheren Radialgeschwindigkeitsmessungen von GCs in Fornax aus der Literatur stelle ich die umfangreichste spektroskopische GC-Stichprobe von 2341 Objekten in dieser Umgebung zusammen. Ich habe herausgefunden, dass rote (metallreiche) GCs meist um Hauptgalaxien herum konzentriert sind, während blaue (metallarme) GCs kinematisch unregelmäßig sind und weit über die Kernregion des Haufens verteilt sind. Ich finde Belege dafür, dass die Substrukturen von Fornax und die Regionen innerhalb des Haufens hauptsächlich von blauen GCs dominiert werden.
Um die baryonische und dunkle Materie der zentralen Galaxie des Fornax-Haufens, NGC 1399, zu verstehen, habe ich die kompilierten Radialgeschwindigkeiten der GCs verwendet, um die Massenmodellierung von NGC 1399 bis zu fünf effektiven Radien durchzuführen. Unter Verwendung der sphärischen Jeans-Modellierung habe ich die Dispersions-Kurtosis-Technik angewandt, um das Massenprofil von NGC 1399 und die orbitale Anisotropie der GCs zu erhalten. Unabhängig von den DM-Haloprofilen, die für die Modellierung verwendet werden, stelle ich fest, dass die Intra-Cluster-GCs eine leichte radiale Anisotropie aufweisen, insbesondere bei blauen, metallarmen GCs.
Außerdem habe ich das Intra-Cluster-Medium (ICM) von Fornax-ähnlichen Halos aus theoretischer Sicht untersucht. Ich nutze die kosmologische Simulation TNG50 in Synergie mit einer laufenden MeerKAT-Radiodurchmusterung des Fornax-Haufens (MFS), um die Verteilung von kaltem Gas im ICM Fornax-ähnlicher Haufen zu verstehen. Unter Anwendung derselben Beobachtungskriterien wie die MFS stelle ich fest, dass TNG50-Halos bei z 0 eine große Menge an HI-Gas innerhalb des Haufens aufweisen. Ich sage voraus, dass die MFS eine HI Verteilung beobachten wird, der einen Flächenanteil von 10% bei einem Virialradius und bis zu 5% für den Intra-Cluster-HI abdeckt.
Im Rahmen dieser Arbeit habe ich den Massenaufbau des Fornax-Haufens untersucht und etwas über sein IC-Medium gelernt. Die Ergebnisse dieser Arbeit veranschaulichen die Bedeutung der GCs für das Verständnis der Entstehungsgeschichte des Fornax-Haufens und legen die Grundlage dafür, dass Intra-Cluster GCs bei der Massenmodellierung unbedingt berücksichtigt werden müssen. Darüber hinaus bietet die Voraussage einer großen Menge kalten Gases in den Fornax-ähnlichen Halos in den TNG50 Simulationen ein spannendes Szenario, das mit zukünftigen Ergebnissen aus der MFS getestet werden kann.Galaxy clusters are the largest gravitationally bound objects in the Universe. They provide the opportunity to explore the baryonic and dark matter distribution on a large physical scale. The Fornax galaxy cluster is one of the densest galaxy clusters in the nearby Universe. Previous photometric studies of Fornax have revealed the presence of stellar and tidal streams within the core and intra-cluster regions. Studies of globular clusters (GC) populations in Fornax have shown an overdensity of GCs connecting several central cluster galaxies. GCs are bright and compact sources that can be used as discrete kinematic tracers to study the stellar population and mass distribution of the galaxies’ outskirts, where field stars are too faint to be directly observed. The goal of this thesis is to explore the mass assembly of the Fornax galaxy cluster using its GC systems.
A crucial piece of information to understand the mass assembly of the Fornax cluster is to comprehend the origin and kinematic behaviour of the intra-cluster GCs. Dynamical mass-modelling of galaxy clusters has shown that ignoring the presence of substructures which are generated by accretion and merger events could impact the mass estimates of clusters. The Fornax cluster provides an excellent opportunity to explore the role of substructures in mass-modelling. In this thesis, I have used the spectroscopic data from the Visible Multi-Object Spectrograph at Very Large Telescope (VLT/VIMOS) from the Fornax cluster VLT spectroscopic survey (FVSS), covering one square degree around the central massive galaxy NGC 1399.
I used VIMOS-FVSS data to kinematically characterize the photometrically discovered GC candidates. With a careful analysis of this data, I confirm a total of 777 GCs, almost doubling previously detected GCs, using the same dataset as was used before. Combined with previous literature radial velocity measurements of GCs in Fornax, I compile the most extensive spectroscopic GC sample of 2341 objects in this environment. I found that red (metal-rich) GCs are mostly concentrated around major galaxies, while blue (metal-poor) GCs are kinematically irregular and are widely spread throughout the core region of the cluster. I find evidence that Fornax substructures and intra-cluster regions are dominated mostly by blue GCs.
To understand the baryonic and dark matter of the central galaxy of the Fornax cluster, NGC1399, I used the complied GCs radial velocities to perform the mass-modelling of NGC1399 out to 5 effective radii. Using spherical Jeans modelling, I applied the dispersion-kurtosis technique to obtain the mass profile of NGC1399 and the orbital anisotropy of GCs. I find that both cusp (NFW) and core (Burkert) halos can produce the observed kinematics. Independent of the DM halo profiles used in modelling, I find that intra-cluster GCs have mild radial anisotropy, especially for blue, metal-poor GCs.
Lastly, I studied the intra-cluster medium (ICM) of Fornax-like halos from a theoretical point of view. I utilize the TNG50 cosmological simulation in synergy with an ongoing MeerKAT radio survey of the Fornax cluster (MFS) to understand the distribution of cold gas in the ICM of Fornax-like clusters. I find that TNG50 halos at z 0, have an abundant amount of intra-cluster HI gas. I predict that MFS will observe an HI covering fraction of 10 % at one virial radius and up to 5 % for the intra-cluster HI.
In summary, I have studied the mass assembly of the Fornax cluster and learned about its IC medium. The results from this thesis illustrate the importance of GCs in understanding the assembly history of the Fornax cluster and lays the foundation for future, more detailed mass-modelling work of intra-cluster GCs. In addition, the prediction of a large amount of cold gas in Fornax-like halos in the TNG50 simulations provides an exciting scenario to be tested with future results from the MFS
The galactic acceleration scale is imprinted on globular cluster systems of early-type galaxies of most masses and on red and blue globular cluster subpopulations
Context. Globular clusters carry information about the formation histories
and gravitational fields of their host galaxies. B\'ilek et al. (2019, BSR19
hereafter) reported that the radial profiles of volume number density of GCs in
GC systems (GCS) follow broken power laws, while the breaks occur approximately
at the radii. These are the radii at which the gravitational fields of
the galaxies equal the galactic acceleration scale ms known from the radial acceleration relation or the MOND
theory of modified dynamics.
Aims. Our main goals here are to explore whether the results of BSR19 hold
true for galaxies of a wider mass range and for the red and blue GCs
sub-populations.
Methods. We exploited catalogs of photometric GC candidates in the Fornax
galaxy cluster based on ground and space observations and a new catalog of
spectroscopic GCs of NGC 1399, the central galaxy of the cluster. For every
galaxy, we obtained the parameters of the broken power law density by fitting
the on-sky distribution of the GC candidates, while allowing for a constant
density of contaminants. The logarithmic stellar masses of our galaxy sample
span 8.0-11.4 .
Results. All investigated GCSs with a sufficient number of members show
broken power-law density profiles. This holds true for the total GC population
and the blue and red subpopulations. The inner and outer slopes and the break
radii agree well for the different GC populations. The break radii agree with
the radii typically within a factor of two for all GC color
subpopulations. The outer slopes correlate better with the radii than
with the galactic stellar masses. The break radii of NGC 1399 vary in azimuth,
such that they are greater toward and against the neighboring galaxy NGC 1404.Comment: 39 pages, ~15 pages main text, 33 figures, 12 tables. Accepted for
publication in A&
Imprint of the galactic acceleration scale on globular cluster systems: Galaxies in the Fornax Cluster
Dark matter is required in galaxies at galactocentric radii that are larger
than the -radius, which is where the gravitational acceleration generated
by baryons of the galaxy equals the constant ms
known as the galactic acceleration scale. It was found previously for massive
early-type galaxies that the radial number-density profiles of their globular
cluster (GC) systems follow broken power laws and the breaks occur at the
-radii. We have newly analyzed the distribution of GCs around galaxies in
the Fornax cluster in existing photometric catalogs. We found that 1) the
coincidence between -radii and the break radii of globular cluster systems
is valid for early-type galaxies of all masses and, 2) this also applies to the
red and blue sub-populations of GCs separately.Comment: 3 pages, 1 figure. To be published in Memorie della SAI
Coherent States for Isospectral Hamiltonians
We show that for the strictly isospectral Hamiltonians, the corresponding
coherent states are related by a unitary transformation. As an illustration, we
discuss, the example of strictly isospectral one-dimensional harmonic
oscillator Hamiltonians and the associated coherent states.Comment: RevTeX, 9 pages, no figure
Exact operator bosonization of finite number of fermions in one space dimension
We derive an exact operator bosonization of a finite number of fermions in
one space dimension. The fermions can be interacting or noninteracting and can
have an arbitrary hamiltonian, as long as there is a countable basis of states
in the Hilbert space. In the bosonized theory the finiteness of the number of
fermions appears as an ultraviolet cut-off. We discuss implications of this for
the bosonized theory. We also discuss applications of our bosonization to
one-dimensional fermion systems dual to (sectors of) string theory such as LLM
geometries and c=1 matrix model.Comment: 47 pages, 1 figure; (v2) typos correcte
The global burden of adolescent and young adult cancer in 2019 : a systematic analysis for the Global Burden of Disease Study 2019
Background In estimating the global burden of cancer, adolescents and young adults with cancer are often overlooked, despite being a distinct subgroup with unique epidemiology, clinical care needs, and societal impact. Comprehensive estimates of the global cancer burden in adolescents and young adults (aged 15-39 years) are lacking. To address this gap, we analysed results from the Global Burden of Diseases, Injuries, and Risk Factors Study (GBD) 2019, with a focus on the outcome of disability-adjusted life-years (DALYs), to inform global cancer control measures in adolescents and young adults. Methods Using the GBD 2019 methodology, international mortality data were collected from vital registration systems, verbal autopsies, and population-based cancer registry inputs modelled with mortality-to-incidence ratios (MIRs). Incidence was computed with mortality estimates and corresponding MIRs. Prevalence estimates were calculated using modelled survival and multiplied by disability weights to obtain years lived with disability (YLDs). Years of life lost (YLLs) were calculated as age-specific cancer deaths multiplied by the standard life expectancy at the age of death. The main outcome was DALYs (the sum of YLLs and YLDs). Estimates were presented globally and by Socio-demographic Index (SDI) quintiles (countries ranked and divided into five equal SDI groups), and all estimates were presented with corresponding 95% uncertainty intervals (UIs). For this analysis, we used the age range of 15-39 years to define adolescents and young adults. Findings There were 1.19 million (95% UI 1.11-1.28) incident cancer cases and 396 000 (370 000-425 000) deaths due to cancer among people aged 15-39 years worldwide in 2019. The highest age-standardised incidence rates occurred in high SDI (59.6 [54.5-65.7] per 100 000 person-years) and high-middle SDI countries (53.2 [48.8-57.9] per 100 000 person-years), while the highest age-standardised mortality rates were in low-middle SDI (14.2 [12.9-15.6] per 100 000 person-years) and middle SDI (13.6 [12.6-14.8] per 100 000 person-years) countries. In 2019, adolescent and young adult cancers contributed 23.5 million (21.9-25.2) DALYs to the global burden of disease, of which 2.7% (1.9-3.6) came from YLDs and 97.3% (96.4-98.1) from YLLs. Cancer was the fourth leading cause of death and tenth leading cause of DALYs in adolescents and young adults globally. Interpretation Adolescent and young adult cancers contributed substantially to the overall adolescent and young adult disease burden globally in 2019. These results provide new insights into the distribution and magnitude of the adolescent and young adult cancer burden around the world. With notable differences observed across SDI settings, these estimates can inform global and country-level cancer control efforts. Copyright (C) 2021 The Author(s). Published by Elsevier Ltd.Peer reviewe
Cancer Incidence, Mortality, Years of Life Lost, Years Lived With Disability, and Disability-Adjusted Life Years for 29 Cancer Groups From 2010 to 2019: A Systematic Analysis for the Global Burden of Disease Study 2019.
The Global Burden of Diseases, Injuries, and Risk Factors Study 2019 (GBD 2019) provided systematic estimates of incidence, morbidity, and mortality to inform local and international efforts toward reducing cancer burden. To estimate cancer burden and trends globally for 204 countries and territories and by Sociodemographic Index (SDI) quintiles from 2010 to 2019. The GBD 2019 estimation methods were used to describe cancer incidence, mortality, years lived with disability, years of life lost, and disability-adjusted life years (DALYs) in 2019 and over the past decade. Estimates are also provided by quintiles of the SDI, a composite measure of educational attainment, income per capita, and total fertility rate for those younger than 25 years. Estimates include 95% uncertainty intervals (UIs). In 2019, there were an estimated 23.6 million (95% UI, 22.2-24.9 million) new cancer cases (17.2 million when excluding nonmelanoma skin cancer) and 10.0 million (95% UI, 9.36-10.6 million) cancer deaths globally, with an estimated 250 million (235-264 million) DALYs due to cancer. Since 2010, these represented a 26.3% (95% UI, 20.3%-32.3%) increase in new cases, a 20.9% (95% UI, 14.2%-27.6%) increase in deaths, and a 16.0% (95% UI, 9.3%-22.8%) increase in DALYs. Among 22 groups of diseases and injuries in the GBD 2019 study, cancer was second only to cardiovascular diseases for the number of deaths, years of life lost, and DALYs globally in 2019. Cancer burden differed across SDI quintiles. The proportion of years lived with disability that contributed to DALYs increased with SDI, ranging from 1.4% (1.1%-1.8%) in the low SDI quintile to 5.7% (4.2%-7.1%) in the high SDI quintile. While the high SDI quintile had the highest number of new cases in 2019, the middle SDI quintile had the highest number of cancer deaths and DALYs. From 2010 to 2019, the largest percentage increase in the numbers of cases and deaths occurred in the low and low-middle SDI quintiles. The results of this systematic analysis suggest that the global burden of cancer is substantial and growing, with burden differing by SDI. These results provide comprehensive and comparable estimates that can potentially inform efforts toward equitable cancer control around the world.Funding/Support: The Institute for Health Metrics and Evaluation received funding from the Bill & Melinda Gates Foundation and the American Lebanese Syrian Associated Charities. Dr Aljunid acknowledges the Department of Health Policy and Management of Kuwait University and the International Centre for Casemix and Clinical Coding, National University of Malaysia for the approval and support to participate in this research project. Dr Bhaskar acknowledges institutional support from the NSW Ministry of Health and NSW Health Pathology. Dr Bärnighausen was supported by the Alexander von Humboldt Foundation through the Alexander von Humboldt Professor award, which is funded by the German Federal Ministry of Education and Research. Dr Braithwaite acknowledges funding from the National Institutes of Health/ National Cancer Institute. Dr Conde acknowledges financial support from the European Research Council ERC Starting Grant agreement No 848325. Dr Costa acknowledges her grant (SFRH/BHD/110001/2015), received by Portuguese national funds through Fundação para a Ciência e Tecnologia, IP under the Norma Transitória grant DL57/2016/CP1334/CT0006. Dr Ghith acknowledges support from a grant from Novo Nordisk Foundation (NNF16OC0021856). Dr Glasbey is supported by a National Institute of Health Research Doctoral Research Fellowship. Dr Vivek Kumar Gupta acknowledges funding support from National Health and Medical Research Council Australia. Dr Haque thanks Jazan University, Saudi Arabia for providing access to the Saudi Digital Library for this research study. Drs Herteliu, Pana, and Ausloos are partially supported by a grant of the Romanian National Authority for Scientific Research and Innovation, CNDS-UEFISCDI, project number PN-III-P4-ID-PCCF-2016-0084. Dr Hugo received support from the Higher Education Improvement Coordination of the Brazilian Ministry of Education for a sabbatical period at the Institute for Health Metrics and Evaluation, between September 2019 and August 2020. Dr Sheikh Mohammed Shariful Islam acknowledges funding by a National Heart Foundation of Australia Fellowship and National Health and Medical Research Council Emerging Leadership Fellowship. Dr Jakovljevic acknowledges support through grant OI 175014 of the Ministry of Education Science and Technological Development of the Republic of Serbia. Dr Katikireddi acknowledges funding from a NHS Research Scotland Senior Clinical Fellowship (SCAF/15/02), the Medical Research Council (MC_UU_00022/2), and the Scottish Government Chief Scientist Office (SPHSU17). Dr Md Nuruzzaman Khan acknowledges the support of Jatiya Kabi Kazi Nazrul Islam University, Bangladesh. Dr Yun Jin Kim was supported by the Research Management Centre, Xiamen University Malaysia (XMUMRF/2020-C6/ITCM/0004). Dr Koulmane Laxminarayana acknowledges institutional support from Manipal Academy of Higher Education. Dr Landires is a member of the Sistema Nacional de Investigación, which is supported by Panama’s Secretaría Nacional de Ciencia, Tecnología e Innovación. Dr Loureiro was supported by national funds through Fundação para a Ciência e Tecnologia under the Scientific Employment Stimulus–Institutional Call (CEECINST/00049/2018). Dr Molokhia is supported by the National Institute for Health Research Biomedical Research Center at Guy’s and St Thomas’ National Health Service Foundation Trust and King’s College London. Dr Moosavi appreciates NIGEB's support. Dr Pati acknowledges support from the SIAN Institute, Association for Biodiversity Conservation & Research. Dr Rakovac acknowledges a grant from the government of the Russian Federation in the context of World Health Organization Noncommunicable Diseases Office. Dr Samy was supported by a fellowship from the Egyptian Fulbright Mission Program. Dr Sheikh acknowledges support from Health Data Research UK. Drs Adithi Shetty and Unnikrishnan acknowledge support given by Kasturba Medical College, Mangalore, Manipal Academy of Higher Education. Dr Pavanchand H. Shetty acknowledges Manipal Academy of Higher Education for their research support. Dr Diego Augusto Santos Silva was financed in part by the Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - Brasil Finance Code 001 and is supported in part by CNPq (302028/2018-8). Dr Zhu acknowledges the Cancer Prevention and Research Institute of Texas grant RP210042
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Global burden of 288 causes of death and life expectancy decomposition in 204 countries and territories and 811 subnational locations, 1990–2021: a systematic analysis for the Global Burden of Disease Study 2021
BACKGROUND Regular, detailed reporting on population health by underlying cause of death is fundamental for public health decision making. Cause-specific estimates of mortality and the subsequent effects on life expectancy worldwide are valuable metrics to gauge progress in reducing mortality rates. These estimates are particularly important following large-scale mortality spikes, such as the COVID-19 pandemic. When systematically analysed, mortality rates and life expectancy allow comparisons of the consequences of causes of death globally and over time, providing a nuanced understanding of the effect of these causes on global populations. METHODS The Global Burden of Diseases, Injuries, and Risk Factors Study (GBD) 2021 cause-of-death analysis estimated mortality and years of life lost (YLLs) from 288 causes of death by age-sex-location-year in 204 countries and territories and 811 subnational locations for each year from 1990 until 2021. The analysis used 56 604 data sources, including data from vital registration and verbal autopsy as well as surveys, censuses, surveillance systems, and cancer registries, among others. As with previous GBD rounds, cause-specific death rates for most causes were estimated using the Cause of Death Ensemble model-a modelling tool developed for GBD to assess the out-of-sample predictive validity of different statistical models and covariate permutations and combine those results to produce cause-specific mortality estimates-with alternative strategies adapted to model causes with insufficient data, substantial changes in reporting over the study period, or unusual epidemiology. YLLs were computed as the product of the number of deaths for each cause-age-sex-location-year and the standard life expectancy at each age. As part of the modelling process, uncertainty intervals (UIs) were generated using the 2·5th and 97·5th percentiles from a 1000-draw distribution for each metric. We decomposed life expectancy by cause of death, location, and year to show cause-specific effects on life expectancy from 1990 to 2021. We also used the coefficient of variation and the fraction of population affected by 90% of deaths to highlight concentrations of mortality. Findings are reported in counts and age-standardised rates. Methodological improvements for cause-of-death estimates in GBD 2021 include the expansion of under-5-years age group to include four new age groups, enhanced methods to account for stochastic variation of sparse data, and the inclusion of COVID-19 and other pandemic-related mortality-which includes excess mortality associated with the pandemic, excluding COVID-19, lower respiratory infections, measles, malaria, and pertussis. For this analysis, 199 new country-years of vital registration cause-of-death data, 5 country-years of surveillance data, 21 country-years of verbal autopsy data, and 94 country-years of other data types were added to those used in previous GBD rounds. FINDINGS The leading causes of age-standardised deaths globally were the same in 2019 as they were in 1990; in descending order, these were, ischaemic heart disease, stroke, chronic obstructive pulmonary disease, and lower respiratory infections. In 2021, however, COVID-19 replaced stroke as the second-leading age-standardised cause of death, with 94·0 deaths (95% UI 89·2-100·0) per 100 000 population. The COVID-19 pandemic shifted the rankings of the leading five causes, lowering stroke to the third-leading and chronic obstructive pulmonary disease to the fourth-leading position. In 2021, the highest age-standardised death rates from COVID-19 occurred in sub-Saharan Africa (271·0 deaths [250·1-290·7] per 100 000 population) and Latin America and the Caribbean (195·4 deaths [182·1-211·4] per 100 000 population). The lowest age-standardised death rates from COVID-19 were in the high-income super-region (48·1 deaths [47·4-48·8] per 100 000 population) and southeast Asia, east Asia, and Oceania (23·2 deaths [16·3-37·2] per 100 000 population). Globally, life expectancy steadily improved between 1990 and 2019 for 18 of the 22 investigated causes. Decomposition of global and regional life expectancy showed the positive effect that reductions in deaths from enteric infections, lower respiratory infections, stroke, and neonatal deaths, among others have contributed to improved survival over the study period. However, a net reduction of 1·6 years occurred in global life expectancy between 2019 and 2021, primarily due to increased death rates from COVID-19 and other pandemic-related mortality. Life expectancy was highly variable between super-regions over the study period, with southeast Asia, east Asia, and Oceania gaining 8·3 years (6·7-9·9) overall, while having the smallest reduction in life expectancy due to COVID-19 (0·4 years). The largest reduction in life expectancy due to COVID-19 occurred in Latin America and the Caribbean (3·6 years). Additionally, 53 of the 288 causes of death were highly concentrated in locations with less than 50% of the global population as of 2021, and these causes of death became progressively more concentrated since 1990, when only 44 causes showed this pattern. The concentration phenomenon is discussed heuristically with respect to enteric and lower respiratory infections, malaria, HIV/AIDS, neonatal disorders, tuberculosis, and measles. INTERPRETATION Long-standing gains in life expectancy and reductions in many of the leading causes of death have been disrupted by the COVID-19 pandemic, the adverse effects of which were spread unevenly among populations. Despite the pandemic, there has been continued progress in combatting several notable causes of death, leading to improved global life expectancy over the study period. Each of the seven GBD super-regions showed an overall improvement from 1990 and 2021, obscuring the negative effect in the years of the pandemic. Additionally, our findings regarding regional variation in causes of death driving increases in life expectancy hold clear policy utility. Analyses of shifting mortality trends reveal that several causes, once widespread globally, are now increasingly concentrated geographically. These changes in mortality concentration, alongside further investigation of changing risks, interventions, and relevant policy, present an important opportunity to deepen our understanding of mortality-reduction strategies. Examining patterns in mortality concentration might reveal areas where successful public health interventions have been implemented. Translating these successes to locations where certain causes of death remain entrenched can inform policies that work to improve life expectancy for people everywhere. FUNDING Bill & Melinda Gates Foundation
Imprint of the galactic acceleration scale on globular cluster systems: Galaxies in the Fornax Cluster
International audienceDark matter is required in galaxies at galactocentric radii that are larger than the -radius, which is where the gravitational acceleration generated by baryons of the galaxy equals the constant ms known as the galactic acceleration scale. It was found previously for massive early-type galaxies that the radial number-density profiles of their globular cluster (GC) systems follow broken power laws and the breaks occur at the -radii. We have newly analyzed the distribution of GCs around galaxies in the Fornax cluster in existing photometric catalogs. We found that 1) the coincidence between -radii and the break radii of globular cluster systems is valid for early-type galaxies of all masses and, 2) this also applies to the red and blue sub-populations of GCs separately
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