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1.
Innovation (Camb) ; 5(5): 100663, 2024 Sep 09.
Artículo en Inglés | MEDLINE | ID: mdl-39071219

RESUMEN

Research on returned samples can provide ground truth for the study of the geological evolution history of the Moon. However, previous missions all collected samples from the near side of the Moon, which is significantly different from the far side of the Moon in terms of the thickness of the lunar crust, magma activity, and composition. Therefore, the samples from the far side of the Moon are of great significance for a comprehensive understanding of the history of the Moon. China's Chang'e-6 (CE-6) probe has successfully landed on the lunar far side and will return samples in the coming days. With the precise location of the CE-6 landing site, a detailed analysis of the geological background is conducted in this research. The landing site of CE-6 is within the Apollo crater, which is inside the largest impact basin on the Moon, i.e., the South Pole-Aitken (SPA) basin. According to the numerical simulation of the formation process of the SPA basin, CE-6 landed at the edge of the SPA impact melting zone, which is presumably composed of impact melt of the lunar mantle. The Apollo crater subsequently excavated deep material again, which constitutes the basement of the CE-6 landing area. Later, erupted basalt covered these basement rocks, and they also constitute the main source of the CE-6 samples. Based on the dating method of crater size-frequency distribution, we find that the basalt is ∼2.50 Ga. The CE-6 samples also possibly contain basement rocks as excavated and ejected by craters, and they can provide crucial information for our understanding of lunar geological history along with the basalt samples.

2.
Proc Natl Acad Sci U S A ; 121(30): e2405160121, 2024 Jul 23.
Artículo en Inglés | MEDLINE | ID: mdl-38976765

RESUMEN

Due to the scarcity of rock samples, the Hadean Era predating 4 billion years ago (Ga) poses challenges in understanding geological processes like subaerial weathering and plate tectonics that are critical for the evolution of life. The Jack Hills zircon from Western Australia, the primary Hadean samples available, offer valuable insights into magma sources and tectonic genesis through trace element signatures. However, a consensus on these signatures has not been reached. To address this, we developed a machine learning classifier capable of deciphering the geochemical fingerprints of zircon. This allowed us to identify the oldest detrital zircon originating from sedimentary-derived "S-type" granites. Our results indicate the presence of S-type granites as early as 4.24 Ga, persisting throughout the Hadean into the Archean. Examining global detrital zircon across Earth's history reveals consistent supercontinent-like cycles from the present back to the Hadean. These findings suggest that a significant amount of Hadean continental crust was exposed, weathered into sediments, and incorporated into the magma sources of Jack Hills zircon. Only the early operation of both subaerial weathering and plate subduction can account for the prevalence of S-type granites we observe. Additionally, the periodic evolution of S-type granite proportions implies that subduction-driven tectonic cycles were active during the Hadean, at least around 4.2 Ga. The evidence thus points toward an early Earth resembling the modern Earth in terms of active tectonics and habitable surface conditions. This suggests the potential for life to originate in environments like warm ponds rather than extreme hydrothermal settings.

4.
Front Endocrinol (Lausanne) ; 15: 1396465, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38919480

RESUMEN

Background: The Oxidative Balance Score (OBS), which quantifies the balance between antioxidants and pro-oxidants influenced by diet and lifestyle, is crucial given oxidative stress's significant role in Chronic Kidney Disease (CKD). This study aims to determine the association between OBS and CKD using data from the National Health and Nutrition Examination Survey (NHANES) 1999-2018. Methods: We analyzed data from the National Health and Nutrition Examination Survey (NHANES) spanning 1999 to 2018. OBS was constructed from a detailed array of 20 factors, including dietary nutrients and lifestyle behaviors. The relationship between OBS and CKD risk was evaluated using weighted logistic regression models, adjusted for potential confounders, with a generalized additive model (GAM) examining non-linear associations. Subgroup analyses and interaction effects across diverse demographic and clinical groups, along with sensitivity analyses, were performed to validate the findings. Results: Among 32,120 participants analyzed, 4,786 were identified with CKD. Fully adjusted weighted logistic regression analysis revealed that each unit increase in OBS was associated with a 2% reduction in CKD prevalence [OR: 0.98 (0.98-0.99), P < 0.001]. Higher OBS quartiles were significantly correlated with a decreased CKD risk [Q4 vs. Q1: OR: 0.82 (0.68-0.98), P = 0.03; P for trend = 0.01]. The GAM and smoothed curve fit indicated a linear relationship between OBS and the risk of CKD. Stratified and sensitivity analyses further substantiated the inverse relationship between OBS and CKD prevalence. Conclusions: Our findings from the NHANES data affirm a significant inverse association between OBS and CKD risk in the U.S. population, underscoring the role of optimizing dietary and lifestyle factors in managing CKD risk. These results advocate for incorporating OBS considerations into CKD prevention and treatment strategies.


Asunto(s)
Encuestas Nutricionales , Estrés Oxidativo , Insuficiencia Renal Crónica , Humanos , Insuficiencia Renal Crónica/epidemiología , Insuficiencia Renal Crónica/metabolismo , Femenino , Masculino , Persona de Mediana Edad , Adulto , Anciano , Estilo de Vida , Dieta , Estudios Transversales , Prevalencia , Factores de Riesgo , Antioxidantes/metabolismo , Estados Unidos/epidemiología
6.
Sci Bull (Beijing) ; 69(13): 2136-2148, 2024 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-38777682

RESUMEN

Lunar exploration is deemed crucial for uncovering the origins of the Earth-Moon system and is the first step for advancing humanity's exploration of deep space. Over the past decade, the Chinese Lunar Exploration Program (CLEP), also known as the Chang'e (CE) Project, has achieved remarkable milestones. It has successfully developed and demonstrated the engineering capability required to reach and return from the lunar surface. Notably, the CE Project has made historic firsts with the landing and on-site exploration of the far side of the Moon, along with the collection of the youngest volcanic samples from the Procellarum KREEP Terrane. These achievements have significantly enhanced our understanding of lunar evolution. Building on this success, China has proposed an ambitious crewed lunar exploration strategy, aiming to return to the Moon for scientific exploration and utilization. This plan encompasses two primary phases: the first crewed lunar landing and exploration, followed by a thousand-kilometer scale scientific expedition to construct a geological cross-section across the lunar surface. Recognizing the limitations of current lunar exploration efforts and China's engineering and technical capabilities, this paper explores the benefits of crewed lunar exploration while leveraging synergies with robotic exploration. The study refines fundamental lunar scientific questions that could lead to significant breakthroughs, considering the respective engineering and technological requirements. This research lays a crucial foundation for defining the objectives of future lunar exploration, emphasizing the importance of crewed missions and offering insights into potential advancements in lunar science.

7.
Natl Sci Rev ; 11(4): nwae063, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38623453

RESUMEN

The Chinese Bayan Obo deposit is a world-class rare earth element (REE) deposit with considerable niobium (Nb) and iron (Fe) resources. A complete genetic understanding on all metals is fundamental for establishing genetic models at Bayan Obo. With extensive research being focused on REE enrichment, the timing and controls of Nb enrichment remain unresolved at Bayan Obo, which is mainly due to the challenges in dating, i.e. multistage thermal events, fine-grained minerals with complex textures and the rare occurrence of uranium-enriched minerals with mature dating methods. Based on robust geological and petrographic frameworks, here we conducted ion probe uranium-lead (U-Pb) dating of ferrocolumbite to unravel the timing, hence the genesis of Nb mineralization. Three types of hydrothermal ferrocolumbites-key Nb-bearing minerals-are identified based on their textures and mineral assemblages. They yield U-Pb ages of 1312 ± 47 Ma (n = 99), 438 ± 7 Ma (n = 93), and 268 ± 5 Ma (n = 19), respectively. In line with deposit geology, we tentatively link the first, second and third stage Nb mineralization to Mesoproterozoic carbonatite magmatism, ubiquitous early Paleozoic hydrothermal activity, and Permian granitic magmatism, respectively. While quantifying the contribution of metal endowment from each stage requires further investigation, our new dates highlight that multi-stage mineralization is critical for Nb enrichment at Bayan Obo, which may also have implications for the enrichment mechanism of Nb in REE deposits in general.

8.
Chron Respir Dis ; 21: 14799731241249474, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38652928

RESUMEN

BACKGROUND: Noninvasive mechanical ventilation (NIV) is recommended as the initial mode of ventilation to treat acute respiratory failure in patients with AECOPD. The Noninvasive Ventilation Outcomes (NIVO) score has been proposed to evaluate the prognosis in patients with AECOPD requiring assisted NIV. However, it is not validated in Chinese patients. METHODS: We used data from the MAGNET AECOPD Registry study, which is a prospective, noninterventional, multicenter, real-world study conducted between September 2017 and July 2021 in China. Data for the potential risk factors of mortality were collected and the NIVO score was calculated, and the in-hospital mortality was evaluated using the NIVO risk score. RESULTS: A total of 1164 patients were included in the study, and 57 patients (4.9%) died during their hospital stay. Multiple logistic regression analysis revealed that age ≥75 years, DBP <60 mmHg, Glasgow Coma Scale ≤14, anemia and BUN >7 mmol/L were independent predictors of in-hospital mortality. The in-hospital mortality was associated with an increase in the risk level of NIVO score and the difference was statistically significant (p < .001). The NIVO risk score showed an acceptable accuracy for predicting the in-hospital mortality in AECOPD requiring assisted NIV (AUC: 0.657, 95% CI: 0.584-0.729, p < .001). CONCLUSION: Our findings identified predictors of mortality in patients with AECOPD receiving NIV, providing useful information to identify severe patients and guide the management of AECOPD. The NIVO score showed an acceptable predictive value for AECOPD receiving NIV in Chinese patients, and additional studies are needed to develop and validate predictive scores based on specific populations.


Asunto(s)
Mortalidad Hospitalaria , Ventilación no Invasiva , Enfermedad Pulmonar Obstructiva Crónica , Humanos , Anciano , Ventilación no Invasiva/estadística & datos numéricos , Masculino , Femenino , Enfermedad Pulmonar Obstructiva Crónica/mortalidad , Enfermedad Pulmonar Obstructiva Crónica/terapia , Factores de Riesgo , Persona de Mediana Edad , China/epidemiología , Estudios Prospectivos , Anciano de 80 o más Años , Factores de Edad , Progresión de la Enfermedad , Escala de Coma de Glasgow , Sistema de Registros , Anemia/terapia , Anemia/mortalidad , Medición de Riesgo/métodos , Pronóstico
9.
Front Endocrinol (Lausanne) ; 15: 1361707, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38633757

RESUMEN

Objective: This study aimed to explore the association between the aspartate aminotransferase to alanine aminotransferase ratio (AST/ALT ratio) and diabetic retinopathy (DR) in patients with type 2 diabetes. Methods: In this cross-sectional study, clinical data from 3002 patients with type 2 diabetes admitted to the Department of Endocrinology of our hospital between January 1, 2021, and December 1, 2022, were retrospectively collected. Measurements of AST and ALT were conducted and diabetes-related complications were screened. The association between AST/ALT ratio and diabetic retinopathy was assessed using multivariate logistic regression, and a generalized additive model (GAM) was used to investigate nonlinear relationships. Subgroup analyses and interaction tests were also conducted. Results: Among the 3002 patients, 1590 (52.96%) were male and 1412 (47.04%) were female. The mean AST/ALT ratio was 0.98 ± 0.32, ranging from 0.37 (Min) to 2.17 (Max). Diabetic retinopathy was present in 40.47% of the patients. After multivariate adjustments, for each 0.1 unit increase in AST/ALT ratio, the risk of DR increased by 4% (OR = 1.04, 95% CI: 1.01-1.07, p=0.0053). Higher AST/ALT ratio quartiles were associated with Higher prevalence of DR (OR vs. Q1: Q4 = 1.34 (CI: 1.03-1.75, p=0.0303).The GAM and smoothed curve fit indicated a linear relationship between AST/ALT ratio and DR risk, with no significant interaction effects across different subgroups. Conclusion: Our study demonstrates a positive correlation between the AST/ALT ratio and diabetic retinopathy risk in type 2 diabetes, suggesting its potential role in assessing DR risk.


Asunto(s)
Alanina Transaminasa , Aspartato Aminotransferasas , Diabetes Mellitus Tipo 2 , Retinopatía Diabética , Femenino , Humanos , Masculino , Alanina Transaminasa/análisis , Alanina Transaminasa/sangre , Estudios Transversales , Diabetes Mellitus Tipo 2/complicaciones , Retinopatía Diabética/sangre , Retinopatía Diabética/diagnóstico , Estudios Retrospectivos , Aspartato Aminotransferasas/análisis , Aspartato Aminotransferasas/sangre , Biomarcadores , Factores de Riesgo
10.
BMC Pulm Med ; 24(1): 125, 2024 Mar 11.
Artículo en Inglés | MEDLINE | ID: mdl-38468263

RESUMEN

BACKGROUND: Data related to the characteristics, treatments and clinical outcomes of acute exacerbation of chronic obstructive pulmonary disease (AECOPD) patients in China are limited, and sex differences are still a neglected topic. METHODS: The patients hospitalized for AECOPD were prospectively enrolled from ten medical centers in China between September 2017 and July 2021. Patients from some centers received follow-up for 3 years. Data regarding the characteristics, treatments and in-hospital and long-term clinical outcomes from male and female AECOPD patients included in the cohort were analyzed and compared. RESULTS: In total, 14,007 patients with AECOPD were included in the study, and 11,020 (78.7%) were males. Compared with males, female patients were older (74.02 ± 10.79 vs. 71.86 ± 10.23 years, P < 0.001), and had more comorbidities (2.22 ± 1.64 vs. 1.73 ± 1.56, P < 0.001), a higher frequency of altered mental status (5.0% vs. 2.9%, P < 0.001), lower diastolic blood pressure (78.04 ± 12.96 vs. 79.04 ± 12.47 mmHg, P < 0.001). In addition, there were also significant sex differences in a range of laboratory and radiographic findings. Females were more likely to receive antibiotics, high levels of respiratory support and ICU admission than males. The in-hospital and 3-year mortality were not significantly different between males and females (1.4% vs. 1.5%, P = 0.711; 35.3% vs. 31.4%, P = 0.058), while female smokers with AECOPD had higher in-hospital mortality than male smokers (3.3% vs. 1.2%, P = 0.002) and male smokers exhibited a trend toward higher 3-year mortality compared to female smokers (40.7% vs. 33.1%, P = 0.146). CONCLUSIONS: In AECOPD inpatients, females and males had similar in-hospital and long-term survival despite some sex differences in clinical characteristics and treatments, but female smokers had significantly worse in-hospital outcomes than male smokers. CLINICAL TRIAL REGISTRATION: Retrospectively registered, registration number is ChiCTR2100044625, date of registration 21/03/2021. URL: http://www.chictr.org.cn/showproj.aspx?proj=121626 .


Asunto(s)
Pacientes Internos , Enfermedad Pulmonar Obstructiva Crónica , Femenino , Humanos , Masculino , Estudios de Cohortes , Progresión de la Enfermedad , Hospitales , Enfermedad Pulmonar Obstructiva Crónica/epidemiología , Enfermedad Pulmonar Obstructiva Crónica/terapia , Caracteres Sexuales , Anciano , Persona de Mediana Edad , Anciano de 80 o más Años
11.
Respir Res ; 25(1): 89, 2024 Feb 10.
Artículo en Inglés | MEDLINE | ID: mdl-38341529

RESUMEN

BACKGROUND: The morbidity and mortality among hospital inpatients with AECOPD and CVDs remains unacceptably high. Currently, no risk score for predicting mortality has been specifically developed in patients with AECOPD and CVDs. We therefore aimed to derive and validate a simple clinical risk score to assess individuals' risk of poor prognosis. STUDY DESIGN AND METHODS: We evaluated inpatients with AECOPD and CVDs in a prospective, noninterventional, multicenter cohort study. We used multivariable logistic regression analysis to identify the independent prognostic risk factors and created a risk score model according to patients' data from a derivation cohort. Discrimination was evaluated by the area under the receiver-operating characteristic curve (AUC), and calibration was assessed by the Hosmer-Lemeshow goodness-of-fit test. The model was validated and compared with the BAP-65, CURB-65, DECAF and NIVO models in a validation cohort. RESULTS: We derived a combined risk score, the ABCDMP score, that included the following variables: age > 75 years, BUN > 7 mmol/L, consolidation, diastolic blood pressure ≤ 60 mmHg, mental status altered, and pulse > 109 beats/min. Discrimination (AUC 0.847, 95% CI, 0.805-0.890) and calibration (Hosmer‒Lemeshow statistic, P = 0.142) were good in the derivation cohort and similar in the validation cohort (AUC 0.811, 95% CI, 0.755-0.868). The ABCDMP score had significantly better predictivity for in-hospital mortality than the BAP-65, CURB-65, DECAF, and NIVO scores (all P < 0.001). Additionally, the new score also had moderate predictive performance for 3-year mortality and can be used to stratify patients into different management groups. CONCLUSIONS: The ABCDMP risk score could help predict mortality in AECOPD and CVDs patients and guide further clinical research on risk-based treatment. CLINICAL TRIAL REGISTRATION: Chinese Clinical Trail Registry NO.:ChiCTR2100044625; URL: http://www.chictr.org.cn/showproj.aspx?proj=121626 .


Asunto(s)
Enfermedades Cardiovasculares , Enfermedad Pulmonar Obstructiva Crónica , Humanos , Anciano , Estudios de Cohortes , Enfermedades Cardiovasculares/diagnóstico , Estudios Prospectivos , Factores de Riesgo , Mortalidad Hospitalaria , Estudios Retrospectivos
12.
Sci Rep ; 14(1): 4016, 2024 02 18.
Artículo en Inglés | MEDLINE | ID: mdl-38369636

RESUMEN

This study aimed to explore the association between serum albumin (ALB) levels and diabetic retinopathy in patients with type 2 diabetes. In this cross-sectional study, we retrospectively collected clinical data from patients with type 2 diabetes who were admitted to the Endocrinology Department of the Affiliated Hospital of Qingdao University between January 1, 2021, and December 1, 2022. All included patients underwent measurements of serum albumin levels and screening for diabetes-related complications. The association between serum albumin levels and retinopathy was assessed using logistic regression after adjusting for potential confounders. Further, stratified analyses and curve fitting were conducted to delve deeper into the relationship. After inclusion and exclusion criteria were applied, a total of 1947 patients were analyzed. Among these, 982 were male and 965 were female. The mean serum albumin level was 39.86 ± 3.27 g/L. Diabetic retinopathy was present in 41.24% of the patients. After adjusting for potential confounders, we observed a significant inverse association between serum albumin levels and the incidence of retinopathy. Specifically, for every 10 g/L increase in albumin level, the odds of retinopathy decreased (odds ratio [OR] = 0.67; 95% confidence interval [CI] = 0.48-0.94; P = 0.0209).The curve fitting validated the inverse relationship between serum albumin and retinopathy without evidence of non-linearity or threshold saturation effects. Stratified analyses consistently indicated no interaction effects across subgroups. This cross-sectional study identified a significant inverse relationship between serum albumin levels and diabetic retinopathy in patients with type 2 diabetes. However, due to the cross-sectional nature of this study, further prospective studies are warranted to confirm these findings.


Asunto(s)
Diabetes Mellitus Tipo 2 , Retinopatía Diabética , Humanos , Masculino , Femenino , Diabetes Mellitus Tipo 2/complicaciones , Retinopatía Diabética/diagnóstico , Estudios Transversales , Estudios Retrospectivos , Albúmina Sérica , Factores de Riesgo
13.
Sci Bull (Beijing) ; 69(5): 601-605, 2024 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-38171964
14.
Artículo en Inglés | MEDLINE | ID: mdl-38249828

RESUMEN

Background: The Rome severity classification is an objective assessment tool for the severity of acute exacerbations of chronic obstructive pulmonary disease (AECOPD) based on readily measurable variables but has not been widely validated. The aim of this study is to evaluate the validity of the Rome classification in distinguishing the severity of AECOPD based on short-term mortality and other adverse outcomes. Methods: The Rome severity classification was applied to a large multicenter cohort of inpatients with AECOPD. Differences in clinical features, in-hospital and 60-day mortality, intensive care unit (ICU) admission, mechanical ventilation (MV) and invasive mechanical ventilation (IMV) usage were compared among the mild, moderate and severe AECOPD according to the Rome proposal. Moreover, univariate logistic analysis and Kaplan Meier survival analysis were also performed to find the association between the Rome severity classification and those adverse outcomes. Results: A total of 7712 patients hospitalized for AECOPD were included and classified into mild (41.88%), moderate (40.33%), or severe (17.79%) group according to the Rome proposal. The rate of ICU admission (6.4% vs 12.0% vs 14.9%, P <0.001), MV (11.7% vs 33.7% vs 45.3%, P <0.001) and IMV (1.4% vs 6.8% vs 8.9%, P <0.001) increased significantly with the increase of severity classification from mild to moderate to severe AECOPD. The 60-day mortality was higher in the moderate or severe group than in the mild group (3.5% vs 1.9%, 4.3% vs 1.9%, respectively, P <0.05) but showed no difference between the moderate and severe groups (2.6% vs 2.5%, P >0.05), results for in-hospital mortality showed the same trends. Similar findings were observed by univariate logistic analysis and survival analysis. Conclusion: Rome severity classification demonstrated excellent performance in predicting ICU admission and the need for MV or IMV, but how it performs in differentiating short-term mortality still needs to be confirmed.


Asunto(s)
Enfermedad Pulmonar Obstructiva Crónica , Humanos , Enfermedad Pulmonar Obstructiva Crónica/diagnóstico , Enfermedad Pulmonar Obstructiva Crónica/terapia , Ciudad de Roma , Mortalidad Hospitalaria , Hospitalización , Estudios de Cohortes
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