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Abstract This systematic review and meta-analysis estimated the global, regional prevalence, and risk factors of osteoporosis. Prevalence varied greatly according to countries (from 4.1% in Netherlands to 52.0% in Turkey) and continents (from 8.0% in Oceania to 26.9% in Africa). Osteoporosis is a common metabolic bone disorder in the elderly, usually resulting in bone pain and an increased risk of fragility fracture, but few summarized studies have guided global strategies for the disease. Therefore, we pooled the epidemiologic data to estimate the global, regional prevalence, and potential risk factors of osteoporosis. We conducted a comprehensive literature search through PubMed, EMBASE, Web of Science, and Scopus, to identify population-based studies that reported the prevalence of osteoporosis based on the World Health Organization (WHO) criteria. Meta-regression and subgroup analyses were used to explore the sources of heterogeneity. The study was registered in the PROSPERO database (CRD42021285555). Of the 57,933 citations evaluated, 108 individual studies containing 343,704 subjects were included. The global prevalence of osteoporosis and osteopenia was 19.7% (95%CI, 18.0%–21.4%) and 40.4% (95%CI, 36.9%–43.8%). Prevalence varied greatly according to countries (from 4.1% in Netherlands to 52.0% in Turkey) and continents (from Oceania 8.0% to 26.9% in Africa). The prevalence was higher in developing countries (22.1%, 95%CI, 20.1%–24.1%) than in developed countries (14.5%, 95%CI, 11.5%–17.7%). Our study indicates a considerable prevalence of osteoporosis among the general population based on WHO criteria, and the prevalence varies substantially between countries and regions. Future studies with robust evidence are required to explore risk factors to provide effective preventive strategies for the disease.

Bringing ultracold atomic gases into the quantum Hall regime is challenging. We engineered an effective magnetic field in a two-dimensional lattice with an elongated-strip geometry, consisting of the sites of an optical lattice in the long direction and of three internal atomic spin states in the short direction. We imaged the localized states of atomic Bose-Einstein condensates in this strip; via excitation dynamics, we further observed both the skipping orbits of excited atoms traveling down the system's edges, analogous to edge magnetoplasmons in two-dimensional electron systems, and a dynamical Hall effect for bulk excitations. Our technique involves minimal heating, which will be important for spectroscopic measurements of the Hofstadter butterfly and realizations of Laughlin's charge pump.

A bstract In an effective theory of gravity, thermodynamic quantities of black holes receive corrections from the infinite series of higher derivative terms. At the next to leading order, these can be obtained by using only the leading order solution. In this paper, we push forward this property to the next to next to leading order. We propose a formula which yields the Euclidean action of asymptotically flat black holes at the next to next to leading order using only the solution up to and including the next to leading order. Other conserved quantities are derived from the Euclidean action via standard thermodynamic relation. We verify our formula in examples of D -dimensional pure gravity and Einstein-Maxwell theory extended by 4- and 6-derivative terms. Based on our formula, we also prove that for asymptotically flat black holes, the physical quantities are invariant under field redefinitions.

The search continues for nickel oxide-based materials with electronic properties similar to cuprate high-temperature superconductors 1 – 10 . The recent discovery of superconductivity in the doped infinite-layer nickelate NdNiO 2 (refs. 11 , 12 ) has strengthened these efforts. Here, we use X-ray spectroscopy and density functional theory to show that the electronic structure of LaNiO 2 and NdNiO 2 , while similar to the cuprates, includes significant distinctions. Unlike cuprates, the rare-earth spacer layer in the infinite-layer nickelate supports a weakly interacting three-dimensional 5 d metallic state, which hybridizes with a quasi-two-dimensional, strongly correlated state with 3 d x 2 − y 2 symmetry in the NiO 2 layers. Thus, the infinite-layer nickelate can be regarded as a sibling of the rare-earth intermetallics 13 – 15 , which are well known for heavy fermion behaviour, where the NiO 2 correlated layers play an analogous role to the 4 f states in rare-earth heavy fermion compounds. This Kondo- or Anderson-lattice-like ‘oxide-intermetallic’ replaces the Mott insulator as the reference state from which superconductivity emerges upon doping. X-ray spectroscopy and density functional theory are used to show that the electronic structure of the parent compound of superconducting infinite-layer nickelates, while similar to the copper-based high-temperature superconductors, has significant differences.

The Global COVID Vaccine Safety (GCoVS) Project, established in 2021 under the multinational Global Vaccine Data Network™ (GVDN®), facilitates comprehensive assessment of vaccine safety. This study aimed to evaluate the risk of adverse events of special interest (AESI) following COVID-19 vaccination from 10 sites across eight countries. Using a common protocol, this observational cohort study compared observed with expected rates of 13 selected AESI across neurological, haematological, and cardiac outcomes. Expected rates were obtained by participating sites using pre-COVID-19 vaccination healthcare data stratified by age and sex. Observed rates were reported from the same healthcare datasets since COVID-19 vaccination program rollout. AESI occurring up to 42 days following vaccination with mRNA (BNT162b2 and mRNA-1273) and adenovirus-vector (ChAdOx1) vaccines were included in the primary analysis. Risks were assessed using observed versus expected (OE) ratios with 95 % confidence intervals. Prioritised potential safety signals were those with lower bound of the 95 % confidence interval (LBCI) greater than 1.5. Participants included 99,068,901 vaccinated individuals. In total, 183,559,462 doses of BNT162b2, 36,178,442 doses of mRNA-1273, and 23,093,399 doses of ChAdOx1 were administered across participating sites in the study period. Risk periods following homologous vaccination schedules contributed 23,168,335 person-years of follow-up. OE ratios with LBCI > 1.5 were observed for Guillain-Barré syndrome (2.49, 95 % CI: 2.15, 2.87) and cerebral venous sinus thrombosis (3.23, 95 % CI: 2.51, 4.09) following the first dose of ChAdOx1 vaccine. Acute disseminated encephalomyelitis showed an OE ratio of 3.78 (95 % CI: 1.52, 7.78) following the first dose of mRNA-1273 vaccine. The OE ratios for myocarditis and pericarditis following BNT162b2, mRNA-1273, and ChAdOx1 were significantly increased with LBCIs > 1.5. This multi-country analysis confirmed pre-established safety signals for myocarditis, pericarditis, Guillain-Barré syndrome, and cerebral venous sinus thrombosis. Other potential safety signals that require further investigation were identified.

Following recent computational discovery of the Cs2InSbCl6 and Cs2InBiCl6 compounds, density functional theory screening of their fundamental physical properties is warranted to establish their potential as optoelectronic materials. Thus, in this paper, we report the results of detailed calculations of the structural, elastic, electronic, and optical properties of the Cs2InSbCl6 and Cs2InBiCl6 crystals using the full-potential augmented plane wave plus local orbitals method with the generalized gradient approximation (GGA) and Tran–Blaha modified Becke–Johnson potential (TB-mBJ) to model the exchange–correlation interactions. Calculations were performed both with and without including spin–orbit coupling effect. Ab initio molecular dynamics calculations show the thermal stability of the title compounds at 300 K. Predicted elastic constants show that the studied materials exhibit moderate resistant to external stress, strong elastic anisotropy, ductile nature, and mechanical stability. Cs2InSbCl6 and Cs2InBiCl6 are direct bandgap (Г–Г) semiconductors. Calculated optical properties reveal that the title compounds are characterized by strong absorption in a large energy window including the high-energy part of the sun visible spectrum.Graphical abstract

A bstract We consider Einstein gravity minimally coupled to two Maxwell fields and one (real) dilaton scalar. We study the electrically-charged spherically-symmetric and static solutions that are asymptotic to Minkowski spacetime. General solutions are described by four independent parameters: mass M , two electric charges ( Q 1 , Q 2 ) and the scalar charge Σ. For black holes, the scalar charge is not independent, but a function of ( M , Q 1 , Q 2 ). We provide a set of formulae relating the mass to the charges, which allows us to determine Σ( M , Q 1 , Q 2 ) without having to solve the black hole equations. Our results confirm the weaker version of the no-hair theorem conjecture involving one real scalar: it can be turned on in a black hole, but it does not have a continuous independent hairy parameter.

Sustainable education is a crucial aspect of creating a sustainable future, yet it faces several key challenges, including inadequate infrastructure, limited resources, and a lack of awareness and engagement. Artificial intelligence (AI) has the potential to address these challenges and enhance sustainable education by improving access to quality education, creating personalized learning experiences, and supporting data-driven decision-making. One outcome of using AI and Information Technology (IT) systems in sustainable education is the ability to provide students with personalized learning experiences that cater to their unique learning styles and preferences. Additionally, AI systems can provide teachers with data-driven insights into student performance, emotions, and engagement levels, enabling them to tailor their teaching methods and approaches or provide assistance or intervention accordingly. However, the use of AI and IT systems in sustainable education also presents challenges, including issues related to privacy and data security, as well as potential biases in algorithms and machine learning models. Moreover, the deployment of these systems requires significant investments in technology and infrastructure, which can be a challenge for educators. In this review paper, we will provide different perspectives from educators and information technology solution architects to connect education and AI technology. The discussion areas include sustainable education concepts and challenges, technology coverage and outcomes, as well as future research directions. By addressing these challenges and pursuing further research, we can unlock the full potential of these technologies and support a more equitable and sustainable education system.

A bstract We study the first law of thermodynamics of dyonic black strings carrying a linear momentum in type IIA string theory compactified on K3 with leading order α ′ corrections. The low energy effective action contains mixed Chern-Simons terms of the form −2 B (2) ^ tr( R (Γ ± ) ^ R (Γ ± )) which is equivalent to 2 H (3) ^ CS (3) (Γ ± ) up to a total derivative. We find that the naive application of Wald entropy formula leads to two different answers associated with the two formulations of the mixed Chern-Simons terms. Surprisingly, neither of them satisfies the first law of thermodynamics for other conserved charges computed unambiguously using the standard methods. We resolve this problem by carefully evaluating the full infinitesimal Hamiltonian at both infinity and horizon, including contributions from terms proportional to the Killing vector which turn out to be nonvanishing on the horizon and indispensable to establish the first law. We find that the infinitesimal Hamiltionian associated with −2 B (2) ^ tr( R (Γ ± ) ^ R (Γ ± )) requires an improvement via adding a closed but non-exact term, which vanishes when the string does not carry either the magnetic charge or linear momentum. Consequently, both formulations of the mixed Chern-Simons terms yield the same result of the entropy that however does not agree with the Wald entropy formula. In the case of extremal black strings, we also contrast our result with the one obtained from Sen’s approach.

The International Commission on Stratigraphy (ICS) utilises benchmark chronostratigraphies to divide geologic time. The reliability of these records is fundamental to understand past global change. Here we use the most detailed luminescence dating age model yet published to show that the ICS chronology for the Quaternary terrestrial type section at Jingbian, desert marginal Chinese Loess Plateau, is inaccurate. There are large hiatuses and depositional changes expressed across a dynamic gully landform at the site, which demonstrates rapid environmental shifts at the East Asian desert margin. We propose a new independent age model and reconstruct monsoon climate and desert expansion/contraction for the last ~250 ka. Our record demonstrates the dominant influence of ice volume on desert expansion, dust dynamics and sediment preservation, and further shows that East Asian Summer Monsoon (EASM) variation closely matches that of ice volume, but lags insolation by ~5 ka. These observations show that the EASM at the monsoon margin does not respond directly to precessional forcing. A basic requirement for reconstructing past environmental change is accurate understanding of sediment age. Here, the authors show that the interpretation of a benchmark archive in China has been inaccurate, and that ice volume primarily controls desert dynamics, sediment preservation, and precipitation at the site.