39 research outputs found
Isoreticular two-dimensional magnetic coordination polymers prepared through pre-synthetic ligand functionalization
Chemical functionalization is a powerful approach to tailor the physical and chemical properties of two-dimensional materials, increase their processability and stability, tune their functionalities and, even, create new 2D materials. This is typically achieved through post-synthetic functionalization by anchoring molecules on the surface of an exfoliated 2D crystal, but it inevitably alters the long-range structural order of the material. Here we present a pre-synthetic approach that allows the isolation of crystalline, robust, and magnetic functionalized monolayers of coordination polymers. A series of five isoreticular layered magnetic coordination polymers based on Fe(II) centres and different benzimidazole derivatives (bearing a Cl, H, CH3, Br or NH2 side group) were first prepared. On mechanical exfoliation, 2D materials are obtained that retain their long-range structural order and exhibit good mechanical and magnetic properties. This combination, together with the possibility to functionalize their surface at will, makes them good candidates to explore magnetism in the 2D limit and to fabricate mechanical resonators for selective gas sensing
Metal-assisted and solvent-mediated synthesis of two-dimensional triazine structures on gram scale
We thank the German Science Foundation (DFG) for financial support within the grants SFB 765 and SFB 658. M.F.G. and J.P.R. also acknowledge the support of the Cluster of Excellence “Matters of Activity. Image Space Material” funded by the DFG under Germany’s Excellence Strategy EXC 2025-390648296. Furthermore, A.T. acknowledges the DFG for funding within the project TH 1463/12-1. We thank Dr. Andreas Schäfer and Maiko Schulze for solid NMR experiments and we appreciate the effort of Vahid Ahmadi Soureshjani in MALDI-TOF experiments. We acknowledge M. Eng. Jörg M. Stockmann for operating the XPS instrument at the BAM and Prof. Stephanie Reich and Dr. Antonio Setaro for fruitful discussions. 2DTs-HRTEM and -EELS studies were conducted at the Laboratorio de Microscopias Avanzadas, Instituto de Nanociencia de Aragon, Universidad de Zaragoza, Spain. R.A. gratefully acknowledges the support from the Spanish Ministry of Economy and Competitiveness (MINECO) through project grant MAT2016-79776-P (AEI/FEDER, UE) and from the European Union H2020 programs ETN projects “Graphene Flagship” (785219 and 881603), FLAG-ERA - Graphene (MICINN) GATES (PCI2018-093137) and “ESTEEM3” (823717).Peer reviewe
Global, regional, and national burden of low back pain, 1990–2020, its attributable risk factors, and projections to 2050: a systematic analysis of the Global Burden of Disease Study 2021
Background: Low back pain is highly prevalent and the main cause of years lived with disability (YLDs). We present the most up-to-date global, regional, and national data on prevalence and YLDs for low back pain from the Global Burden of Diseases, Injuries, and Risk Factors Study 2021. Methods: Population-based studies from 1980 to 2019 identified in a systematic review, international surveys, US medical claims data, and dataset contributions by collaborators were used to estimate the prevalence and YLDs for low back pain from 1990 to 2020, for 204 countries and territories. Low back pain was defined as pain between the 12th ribs and the gluteal folds that lasted a day or more; input data using alternative definitions were adjusted in a network meta-regression analysis. Nested Bayesian meta-regression models were used to estimate prevalence and YLDs by age, sex, year, and location. Prevalence was projected to 2050 by running a regression on prevalence rates using Socio-demographic Index as a predictor, then multiplying them by projected population estimates. Findings: In 2020, low back pain affected 619 million (95% uncertainty interval 554–694) people globally, with a projection of 843 million (759–933) prevalent cases by 2050. In 2020, the global age-standardised rate of YLDs was 832 per 100 000 (578–1070). Between 1990 and 2020, age-standardised rates of prevalence and YLDs decreased by 10·4% (10·9–10·0) and 10·5% (11·1–10·0), respectively. A total of 38·8% (28·7–47·0) of YLDs were attributed to occupational factors, smoking, and high BMI. Interpretation: Low back pain remains the leading cause of YLDs globally, and in 2020, there were more than half a billion prevalent cases of low back pain worldwide. While age-standardised rates have decreased modestly over the past three decades, it is projected that globally in 2050, more than 800 million people will have low back pain. Challenges persist in obtaining primary country-level data on low back pain, and there is an urgent need for more high-quality, primary, country-level data on both prevalence and severity distributions to improve accuracy and monitor change. Funding: Bill and Melinda Gates Foundation
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Global, regional, and national burden of low back pain, 1990–2020, its attributable risk factors, and projections to 2050: a systematic analysis of the Global Burden of Disease Study 2021
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Global, regional, and national burden of rheumatoid arthritis, 1990–2020, and projections to 2050: a systematic analysis of the Global Burden of Disease Study 2021
Background
Rheumatoid arthritis is a chronic autoimmune inflammatory disease associated with disability and premature death. Up-to-date estimates of the burden of rheumatoid arthritis are required for health-care planning, resource allocation, and prevention. As part of the Global Burden of Diseases, Injuries, and Risk Factors Study (GBD) 2021, we provide updated estimates of the prevalence of rheumatoid arthritis and its associated deaths and disability-adjusted life-years (DALYs) by age, sex, year, and location, with forecasted prevalence to 2050.
Methods
Rheumatoid arthritis prevalence was estimated in 204 countries and territories from 1990 to 2020 using Bayesian meta-regression models and data from population-based studies and medical claims data (98 prevalence and 25 incidence studies). Mortality was estimated from vital registration data with the Cause of Death Ensemble model (CODEm). Years of life lost (YLL) were calculated with use of standard GBD lifetables, and years lived with disability (YLDs) were estimated from prevalence, a meta-analysed distribution of rheumatoid arthritis severity, and disability weights. DALYs were calculated by summing YLLs and YLDs. Smoking was the only risk factor analysed. Rheumatoid arthritis prevalence was forecast to 2050 by logistic regression with Socio-Demographic Index as a predictor, then multiplying by projected population estimates.
Findings
In 2020, an estimated 17·6 million (95% uncertainty interval 15·8–20·3) people had rheumatoid arthritis worldwide. The age-standardised global prevalence rate was 208·8 cases (186·8–241·1) per 100 000 population, representing a 14·1% (12·7–15·4) increase since 1990. Prevalence was higher in females (age-standardised female-to-male prevalence ratio 2·45 [2·40–2·47]). The age-standardised death rate was 0·47 (0·41–0·54) per 100 000 population (38 300 global deaths [33 500–44 000]), a 23·8% (17·5–29·3) decrease from 1990 to 2020. The 2020 DALY count was 3 060 000 (2 320 000–3 860 000), with an age-standardised DALY rate of 36·4 (27·6–45·9) per 100 000 population. YLDs accounted for 76·4% (68·3–81·0) of DALYs. Smoking risk attribution for rheumatoid arthritis DALYs was 7·1% (3·6–10·3). We forecast that 31·7 million (25·8–39·0) individuals will be living with rheumatoid arthritis worldwide by 2050.
Interpretation
Rheumatoid arthritis mortality has decreased globally over the past three decades. Global age-standardised prevalence rate and YLDs have increased over the same period, and the number of cases is projected to continue to increase to the year 2050. Improved access to early diagnosis and treatment of rheumatoid arthritis globally is required to reduce the future burden of the disease.
Funding
Bill & Melinda Gates Foundation, Institute of Bone and Joint Research, and Global Alliance for Musculoskeletal Health
Global, regional, and national incidence of six major immune-mediated inflammatory diseases: findings from the global burden of disease study 2019
Background The causes for immune-mediated inflammatory diseases (IMIDs) are diverse and the incidence trends of IMIDs from specific causes are rarely studied. The study aims to investigate the pattern and trend of IMIDs from 1990 to 2019. Methods We collected detailed information on six major causes of IMIDs, including asthma, inflammatory bowel disease, multiple sclerosis, rheumatoid arthritis, psoriasis, and atopic dermatitis, between 1990 and 2019, derived from the Global Burden of Disease study in 2019. The average annual percent change (AAPC) in number of incidents and age standardized incidence rate (ASR) on IMIDs, by sex, age, region, and causes, were calculated to quantify the temporal trends. Findings In 2019, rheumatoid arthritis, atopic dermatitis, asthma, multiple sclerosis, psoriasis, inflammatory bowel disease accounted 1.59%, 36.17%, 54.71%, 0.09%, 6.84%, 0.60% of overall new IMIDs cases, respectively. The ASR of IMIDs showed substantial regional and global variation with the highest in High SDI region, High-income North America, and United States of America. Throughout human lifespan, the age distribution of incident cases from six IMIDs was quite different. Globally, incident cases of IMIDs increased with an AAPC of 0.68 and the ASR decreased with an AAPC of −0.34 from 1990 to 2019. The incident cases increased across six IMIDs, the ASR of rheumatoid arthritis increased (0.21, 95% CI 0.18, 0.25), while the ASR of asthma (AAPC = −0.41), inflammatory bowel disease (AAPC = −0.72), multiple sclerosis (AAPC = −0.26), psoriasis (AAPC = −0.77), and atopic dermatitis (AAPC = −0.15) decreased. The ASR of overall and six individual IMID increased with SDI at regional and global level. Countries with higher ASR in 1990 experienced a more rapid decrease in ASR. Interpretation The incidence patterns of IMIDs varied considerably across the world. Innovative prevention and integrative management strategy are urgently needed to mitigate the increasing ASR of rheumatoid arthritis and upsurging new cases of other five IMIDs, respectively. Funding The Global Burden of Disease Study is funded by the Bill and Melinda Gates Foundation. The project funded by Scientific Research Fund of Sichuan Academy of Medical Sciences & Sichuan Provincial People's Hospital (2022QN38)
Further Remarks on N-Distance-Balanced Graphs
Throughout this paper, we present a new strong property of graph so-called nicely n-distance-balanced which is notably stronger than the concept of n-distance-balanced recently given by the authors. We also initially introduce a newgraph invariant which modies Szeged index and is suitable to study n-distance-balanced graphs. Looking for the graphs extremal with respect to the modiedSzeged index it turns out the n-distance-balanced graphs with odd integer n arethe only bipartite graphs which can maximize the modied Szeged index and thisalso disproves a conjecture proposed by Khalifeh et al. [Khalifeh M.H.,Youse-Azari H., Ashra A.R., Wagner S.G.: Some new results on distance-based graphinvariants, European J. Combin. 30 (2009) 1149-1163]. Furthermore, we gathersome facts concerning with the nicely n-distance-balanced graphs generated by somewell-known graph products. To enlighten the reader some examples are provided.Moreover, a conjecture and a problem are presented within the results of this article
Some Root Traits of Barley (Hordeum vulgare L.) as Affected by Mycorrhizal Symbiosis under Drought Stress
The effect of drought stress and mycorrhizal symbiosis on the colonization, root and leaf phosphorous content, root and leaf phosphatase activity, root volume and area as well as shoot dry weight of a variety of hulless barley were evaluated using a completely randomized experimental design (CRD) with 3 replications. Treatments were three levels of drought stress of 30, 60 and 90% field capacity and two levels of mycorrhizal with and without inoculation. According to the results, the highest value of leaf phosphorous (1.54 mg/g) was observed at mycorrhizal symbiosis against severe drought treatment. Root phosphatase activity was highest (297.9 OD min -1 FW-1) at severe drought stress with mycorrhizal symbiosis which in comparison with mild stress in the presence of mycorrhiza showed 16.6 fold increasing. The control and non-mycorrhizal symbiosis treatments had highest root dry weight (0.091 g). The lowest root volume (0.016 cm2) observed at mycorrhizal symbiosis × severe drought treatment. Generally, Inoculation of barley seed with mycorrhiza at severe water stress could transport more phosphorous to shoot, especially leaf via inducing of leaf and root phosphatase activity. Also, in addition to supply of nutrient sources especially phosphorous for plant, mycorrhizal symbiosis could play an important role in withstanding water stress in plant via increasing of root dry weight and area
Estimation of LiDAR error over complex terrain covered with forest using numerical tools
Since a few years, a new wind measurement instrument has been competing with standard cup
anemometers: the LiDAR. The performances of this instrument over complex terrain are still
a matter of debate and this is mainly due to the flow homogeneity assumption made by the
instrument. In this work, the error caused by this hypothesis was evaluated with the help
of OpenFOAM 1.7, MeteoDyn WT 4.0 and WAsP Engineering for a LiDAR deployed on a complex
site covered with dense forest. The assessment of the CFD model firstly revealed the
significant impact of both the location and nature of the inlet boundary condition.
Despite the presence of terrain complexity within a radius of 340 m around the remote
sensor, an averaged error of less than 3% was observed, suggesting that the LiDAR is only
affected by topographic variations in the immediate vicinity of the scanned volume
Evaluating COX-2-765 G →C Genetic Polymorphism in Migraineurs
Introduction: Migraine is a common debilitating headache with reversible pain attacks associated with temporal changes in the diameter of head blood vessels. According to the International Classification for the Headache Society, migraineurs are divided into two main categories: migraine with aura and migraine without aura. The present study aimed to investigate the association between COX-2-765G →C genetic polymorphism and the risk of migraine.
Methods: In this study, genomic DNAs related to the blood tissues of 100 migraine patients and 100 controls were extracted and purified. The expected region of COX-2 gene was amplified utilizing the appropriative COX-2-765G→C (rs20417) primer in the PCR process. Then, the enzyme digestion was performed using RFLP manner and Aci I restriction enzyme. Moreover, the SPSS software (version 20) was applied in order to analyze the study data.
Results: The study results revealed that the frequency of the COX-2-765CC and COX-2-765CG genotypes in migraine cases were significantly higher than those of controls.
Conclusion: The study findings demonstrated that COX-2-765G→C polymorphism can increase the risk of migraine susceptibility. However, further studies are necessitated to be conducted on larger samples in different nations in other parts of the world in order to assess the role of COX-2 gene variants in the migraine development