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Knowledge regarding the abundance and distribution of solar wind (SW)‐sourced water (OH/H2O) on the Moon in the shallow subsurface remains limited. Here, we report the NanoSIMS measurements of H abundances and D/H ratios on soil grains from three deepest sections of the Chang'E‐5 drill core sampled at depths of 0.45–0.8 m. High water contents of 0.13–1.3 wt.% are present on approximately half of the grain surfaces (topmost ∼100 nm), comparable to the values of Chang'E‐5 scooped soils. The extremely low δD values (as low as −995‰) and negative correlations between δD and water contents indicate that SW implantation is an important source of water beneath the lunar surface. The results are indicative of homogeneous distribution of SW‐derived water in the vertical direction, providing compelling evidence for the well‐mixed nature of the lunar regolith. Moreover, the findings demonstrate that the shallow subsurface regolith of the Moon contains a considerable amount of water. Plain Language Summary: Recently, China's Chang'E‐5 mission targeted a higher latitude on the Moon than previous Apollo and Luna missions, and brought back scooped and drilled samples to the Earth. These new soil samples provide an opportunity to investigate the distribution, abundance, and origin(s) of water in Moon's middle latitude. Here, we focus on using the NanoSIMS technique to analyze water content on soil near‐surface regions to understand whether the solar wind (SW)‐derived water could be preserved after burial at depth. Our results show that more than half of the core soils have high water contents on the rims of grains, similar to those of the Chang'E‐5 scooped soils. This finding suggests that the SW remains an important source of water in the Moon's subsurface. Our work provides direct evidence that the lunar regolith below the surface contains considerable water from SW implantation. This type of water could be a promising water resource in future exploration. Key Points: More than half of the soils from the single drill core have high water contents and low D/H ratios below the surfaceThe solar wind (SW)‐derived water could be preserved for hundreds of millions of years if buried at depthLunar regolith from the drill core contains considerable water from SW implantation, which is much more accessible [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

A new SIMS U-Pb zircon age of 654.2 ± 2.7 Ma was reported from the middle Datangpo Formation in Changyang County of Hubei Province, China. The age is identical with that of 654 ± 3.8 Ma from the top Datangpo Formation in western Hunan Province, revealing that the volcanic activities (~654 Ma) may have occurred widely in South China. The occurrence of the tuff beds (~654 Ma) at different intervals of the Datangpo Formation indicates that the erosion process after the Datangpo deposition varied significantly in different areas. It is thus consequently suggested that the rift in South China was active until the Nantuo glaciation. In addition, the new age confirms that the Nantuo glaciation started much later than 654 Ma. [ABSTRACT FROM AUTHOR]

Early Yanshanian (Jurassic) granitoids are widespread in the Nanling Range, South China. Whereas large granitic batholiths commonly crop out in the center of the Nanling Range (corresponding geographically to the central and northern parts of Guangdong Province), many small stocks occur in the southern part of Jiangxi Province. Most of the small stocks are associated closely with economically significant rare-metal deposits (W, Sn, Nb, Ta). Here we report the results for biotite granites and two-mica granites from three Yanshanian stocks of the Longyuanba complex. LA-ICPMS U-Pb dating of zircon yields an age of 156.1±2.1 Ma for Xiaomubei biotite granite, and U-Pb zircon dating using SIMS yields an age of 156.7±1.2 Ma for Longyuanba-Chengjiang biotite granite and 156.4±1.3 Ma for Jiangtoudong two-mica granite. Biotite granites are silica-rich (SiO=70%-79%), potassic (KO/NaO>1.9), and peraluminous (ASI=1.05-1.33). Associated samples are invariably enriched in Rb, Th, Pb and LREE, yet depleted in Ba, Nb, Sr, P and Ti, and their REE pattern shows a large fractionation between LREE and HREE ((La/Yb)=10.7-13.5) and a pronounced Eu negative anomaly ( δEu=0.28-0.41). Two-mica granite samples are also silica-rich (SiO=75%-79%), potassic (KO/NaO>1.2), and peraluminous (ASI=1.09-1.17). However, in contrast to the biotite granites, they are more enriched in Rb, Th, Pb and extremely depleted in Ba, Nb, Sr, P and Ti, and exhibit nearly flat ((La/Yb)=0.75-1.08) chondrite-normalized REE patterns characterized by strong Eu depletion ( δEu=0.02-0.04) and clear tetrad effect (TE=1.10-1.14). Biotite granites and two-mica granties have comparable Nd isotopic signatures, and their ɛNd( t) are concentrated in the −13.0 to −9.6 and −11.5 to −7.7 respectively. Their zircon Hf-O isotopes of both also show similarity (biotite granites: ɛHf( t)=−10.8-−7.9, δO=7.98‰-8.89‰ and ɛHf( t)= −13.8 to −9.1, δO=8.31‰-10.08‰; two-mica granites: ɛHf( t)=−11.3 to −8.0, δO=7.91‰-9.77‰). The results show that both biotite and two-mica granites were derived mainly from sedimentary source rocks with a minor contribution from mantle-derived materials. In spite of some S-type characteristics, the biotite granites were formed by fractional crystallization of I-type magma and assimilation of peraluminous sedimentary rocks during their ascent to the surface. Therefore, they belong to highly fractionated I-type granites. Two-mica granites exhibit a tetrad effect in their REE patterns, but share the same isotopic features with the biotite granites, suggesting that they are highly fractionated I-type granites as well. Their Lanthanide tetrad effects may be attributed to the hydrothermal alteration by magmatic fluids that have suffered degassing at late stages. Granitic magmas undergoing fractional crystallization and wall-rock assilimation can generate highly evolved granites with no REE tetrad effect in the uni-phase system. However, in the late-stage of magmatic evolution in the multi-phase system (i.e., magmatic-hydrothermal system), these magmas also can lead to the highly evolved granites exhibiting mew-shaped REE pattern characterized by tetrad effect as the consequence of melt-fluid and fluid-vapor fractionation, and the resultant autometasomatism. We thus suggest that the REE pattern exhibiting tetrad effect feature is an important indicator of rare metal mineralization in the early Yanshanian time in southern China, implying the metamorphism of the ore fluid. [ABSTRACT FROM AUTHOR]

The Baizhangyan skarn-porphyry type W- Mo deposit is located in a newly defined Mo- W- Pb- Zn metallogenic belt, which is in the south of Middle- Lower Yangtze Valley Cu- Fe- Au polymetallic metallogenic belt in SE China. The W- Mo orebodies occur mainly within the contact zone between fine-grained granite and Sinian limestone strata. There are two types of W- Mo mineralization: major skarn W- Mo mineralization and minor granite-hosted disseminated Mo mineralization which was traced by drilling at depth. Eight molybdenite samples from Mo-bearing ores yield Re- Os dates that overlap within analytical error, with a weighted average age of 134.1 ± 2.2 Ma. These dates are in close agreement with SIMS U- Pb concordant zircon age for fine-grained granite at 133.3 ± 1.3 Ma, indicating that crystallization of the granite and hydrothermal molybdenite formation were coeval and likely cogenetic. The Baizhangyan W- Mo deposit formed in the Early Cretaceous extensional tectonic setting at the Middle- Lower Yangtze Valley metallogenic belt and the Jaingnan Ancient Continent. Based on mineral compositions and crosscutting relationships of veinlets, hydrothermal alteration and mineralization, the ore mineral paragenesis of the Baizhangyan deposit is divided into four stages: skarn stage ( I), oxide stage ( II), sulfide stage ( III), and carbonate stage ( IV). Fluid inclusions in garnet, scheelite, quartz and calcite from W- Mo ores are mainly aqueous-rich ( L + V) type inclusions. Following garnet deposition at stage I, the high-temperature fluids gave way to progressively cooler, more dilute fluids associated with tungsten-molybdenite-base metal sulfide deposition (stage II and stage III) (162-360°C, 2.7-13.2 wt % NaCl equivalent) and carbonate deposition (stage IV) (137-190°C, 0.9-5 wt % NaCl equiv.). Hydrogen-oxygen isotope data from minerals of different stages suggest that the ore-forming fluids consisted of magmatic water, mixed in various proportions with meteoric water. From stage I to stage IV, there is a systematic decrease in the homogenization temperature of the fluid-inclusion fluids and calculated δ18O values of the fluids. These suggest that increasing involvement of formation water or meteoric water during the fluid ascent resulted in successive deposition of scheelite and molybdenite at Baizhangyan. [ABSTRACT FROM AUTHOR]

The Jitoushan W–Mo ore body is a typical skarn-type deposit with the potential for porphyry Mo mineralization at depth. As it is newly discovered, only a few studies have been conducted on the geochronology and ore genesis of this deposit. The ore district consists of Cambrian to Silurian sedimentary and low-grade metasedimentary strata, intruded by granodiorite, diorite porphyry, granite porphyry, and quartz porphyry. Skarn W–Mo ore bodies are hosted in the contact zone between the granodiorite and Cambrian limestone strata. Within the granodiorite near the contact zone, quartz vein type and disseminated sulphide mineralization are well developed. The Mo-bearing granite porphyry has been traced at depth by drilling. Our results reveal two discrete magmatic events at ca. 138 and ca. 127 Ma in the study area. The molybdenite Re–Os isochronal age of 136.6 ± 1.5 million years is consistent with the first magmatic event. The zircon Hf isotope (ϵHf(t) = −12.55−3.91), sulphide isotopes (δ34S = 3.32–5.59‰), and Re content of molybdenite (Recontent = 6.424–19.07 μg) indicate that the ore-forming materials were mainly derived from the deep crust. The regional tectonic system switched from a Late Jurassic transpressive regime to an earliest Cretaceous extensional regime at ca. 145 Ma, and at ca. 138 Ma, the Jitoushan W–Mo deposit formed in an extensional setting. [ABSTRACT FROM AUTHOR]

Early Yanshanian (Jurassic) granitoids are widespread in the Nanling Range of South China, and are associated with numerous non-ferrous and rare metal mineral deposits. These granitoids consist mainly of slightly peraluminous biotite monzogranites and K-feldspar granites that are closely associated in time and space with subordinate amphibole-bearing granites and muscovite- and garnet-bearing granites. In most previous studies, the biotite-bearing granites were classified as crustal transformation-type (corresponding to the S-type) granites which were interpreted to be derived from the regional Paleoproterozoic meta-sedimentary rocks. In this paper, we re-analyze the geochemical characteristics of a number of representative Early Yanshanian Nanling granitoids. There exists a clear negative correlation between SiO2 and P2O5 for the studied granitoids. The Early Yanshanian Nanling granitoid suites (including amphibole-bearing granodiorites→biotite monzogranites→K-feldspar granites→two-mica (muscovite) granites) are metaluminous to slightly peraluminous I-type or fractionated I-type granites. They were derived predominantly from Proterozoic igneous protoliths. The juvenile crust and/or newly mantle-derived materials might also have been involved in some of these granites. In addition, the I- and fractionated I-type granites are closely associated in time and space with minor amount of A-type felsic and mafic volcanic and intrusive rocks as well as alkaline rocks. All these rocks constitute a typical assemblage of anorogenic, intraplate magmatism, suggesting a dominant lithospheric extensional regime for the Nanling Range and neighboring region during the Early Yanshanian period. [ABSTRACT FROM AUTHOR]

Discusses the Zircon SHRIMP uranium-lead dating for the Cangshuipu volcanic rocks and its implications for the lower boundary age of the Nanhua strata in South China. Occurrence of the continental volcanic rocks and volcaniclastic sedimentary conglomerates of the Cangshuipu Formulation in Yiyang of Hunan Province; Configuration of the strata in the Yiyang region; Representation of the lower boundary with a younger age than previously reported.

Discusses the Jurassic high Sr/low Y granitoids in eastern China. Finding that they have high Sr/Y and La/Yb ratios and low abundance in Y and Yb; How they compare to adakites defined by Defant and colleagues; How these high Sr/low Y granitoids compare to typical adakites in circum-Pacific margins; Finding of relatively flat HREE patterns with Y/Yb values of -10 close to the chondritic value; Indication that the geochemical characteristics show a residue mineral assemblage of hornblende, garnet and plagioclase for the high Sr/low Y granitoids melt; Conclusion they were generated by partial melting at 9—13 kbar (30—45 km in depth); Similarity to the Archaean high-Al TTG; Assertion that these high Sr/low Y granitoids should not be cited as evidence for a thickened crust and/or the presence of the "Eastern China Plateau" in Jurassic.

Focuses on a study that examined the similarities between the metamorphosed mafic rocks found in Hainan Island, China with depleted N-type mid-ocean ridge basalts. Protolith of the mafic rocks; Methodology of the study; Results and discussion; Conclusion.

Provides information on a study which examined the geological, petrological, and geochemical of a shoshonitic intrusive suite in southeast Guangxi of China. Geological background of the suite; Discussion; Conclusions.

Reports on the diachronous uplift of the Tibetan plateau starting 40 million years ago. What the uplift of the Tibetan plateau is generally regarded as; What magmatic activities suggest; The timing of the events being the subject of great interest for understanding mountain-building processes.

Discusses the measurement of isotopes using the cathodoluminescence imaging and ion microprobe zircon dating, at the uppermost Cretaceous Furao Formation near the Heilong River in China. Features of zircons; Outcrop of the Furaoan Stage in Baitoushan Section; Estimate of the formation age.

The mechanism and timing of crustal growth and differentiation on early Earth are debated. Evidence of crustal differentiation is detectable as deviations from Earth's assumed chondritic uniform reservoir (CHUR) as crust is extracted from the mantle leading to a melt-depleted reservoir. For the long-lived zircon Lu-Hf system, no incontrovertible evidence of significant mantle depletion >3.8 Ga exists. We conduct combined U-Pb and Lu-Hf isotopic analyses for the detrital zircon from the Caozhuang supracrustal sequence in North China. The zircon Hf isotopic compositions are broadly scattered along the CHUR evolution line. However, given the possibility of potential systematic biases in zircon petrogenesis and the unique tectonic setting of early Earth, we posit that magmatism controlled by the nascent forms of plate tectonics during the Eoarchean could have likely hidden the degree of ancient crust-mantle differentiation. The non-depleted zircon Hf isotopes observed in North China and globally during early Earth may in verity imply the existence of ubiquitous depleted mantle domains at that time. [ABSTRACT FROM AUTHOR]

Abstract: Although petrologic data from the North Qinling orogen in central China have provided essential information on the geodynamic history of the orogenic cycle, the timing of the continental collision between the North China block and the South China block in the North Qinling orogen remains essentially unconstrained. To refine existing geodynamic models, two eclogites from the North Qinling were dated by U–Pb and Lu–Hf geochronology. The upper limit of the pressure during the eclogite facies metamorphism was restricted within the quartz stability field at 2.6–2.8GPa within a temperature range of 660–710°C by combining conventional thermobarometry and pseudosection estimates. Mineral–whole rock dating for multi-garnet-(omphacite) fractions from two localities yielded ages of 516.4±5.8Ma (2σ) and 494.3±2.7Ma (2σ) with corresponding weighted mean zircon 206Pb/238U ages of 507.0±8.7Ma (2σ) and 490.0±4.1 (2σ) Ma, respectively. Garnet porphyroblasts from the two samples bore evidence of prograde elemental zonation, but the major portion of the garnet grains grew exclusively under eclogite facies conditions as indicated by the occurrence of omphacite inclusions from core to rim. Therefore, these Lu–Hf ages were interpreted to reflect high-pressure eclogite facies metamorphism. The difference between the two Lu–Hf ages likely represents the minimum duration of garnet growth and thus brackets the onset and the closure of the subduction. These results allow for more detailed insight into the subduction history of the North Qinling orogen. These new U–Pb and Lu–Hf ages mark the timing of the onset of the continental collision between the North China block and the South China block in the Qinling belt, suggesting that the entry of the leading edge of the South China block continent into the North China block trench occurred from ca. 516Ma to 490Ma in the North Qinling orogen. [Copyright &y& Elsevier]

Abstract: Quartz-rich veins, together with their host high-pressure (HP) to ultra-high-pressure (UHP) rocks, are ideal for deciphering the fluid–rock interaction history in subduction zones. Previous studies of samples from Dabie–Sulu have shown that most quartz-rich veins within UHP/HP eclogite were formed during the prograde or early exhumation stage of host rocks. In contrast, a combined study of petrology and U–Pb, Sm–Nd and Lu–Hf geochronologies for a quartz-rich vein and its host retrogressed eclogite from North Qinling, which is associated with a granite intrusion and obliterated with amphibolite-facies overprint, reveals that the amphibolite-facies overprint is likely due to the late regional magmatism and the quartz-rich vein might derive from the nearby granite. A pool of U–Pb analyses of zircon grains from the retrogressed eclogite reveals zircons grew over an extended period of time but with two caveats at ca. 490Ma and ca. 473Ma. Analyses of zircon grains from the quartz vein yield a weighted mean 207Pb/206Pb ages of 428±5Ma (1σ), which is indistinguishable from that of formation of the adjacent granite. Combined elemental zoning patterns in the garnet with the spherical geometry effect, the Lu–Hf age of 416±5Ma (2σ) of the retrogressed eclogite is likely a mix age of eclogite-facies and amphibolite-facies metamorphism while the garnet–amphibole Sm–Nd age of 400±8Ma (2σ) approximates amphibolite-facies retrogression metamorphism. The latter is consistent with the garnet–biotite Sm–Nd age of 393±4Ma (2σ) of the adjacent granite, suggesting contact metamorphism. The >70Myr gap between the eclogite-facies metamorphism and the amphibole-facies overprint and the consistency of the timing the amphibolite-facies overprint for the eclogite and the cooling of the magma intrusion in this area indicate that the eclogite-facies metamorphism and amphibolite-facies metamorphism might be distinct metamorphic events, and the latter might be trigged by the granite intrusion. [Copyright &y& Elsevier]

Abstract: Hydrocarbon migration pathways are the linkage between hydrocarbon source areas and accumulation sites. Modeling accurately the pathways of hydrocarbon migration is of important significance in determining the location of favorable petroleum exploration targets. In this paper, GIS-based modeling algorithms are presented for searching the pathways of secondary hydrocarbon migration by considering the geologic mechanisms. These algorithms are constructed on a raster digital elevation model (DEM) of the top boundary of a carrier bed, in which secondary migration occurred. On the DEM, a 3×3 pixel sized window is used for searching. The center of the search window is initially assumed at a point on the boundary of a hydrocarbon source area, from which the secondary hydrocarbon migration starts. The altitude values in the eight adjoining pixels enclosing the central pixel of the search window are compared, and the pixel with an altitude value not only larger than the central pixel but also the largest of the eight surrounding pixels is the next target pixel where the search window will move to. Each searched path will terminate at either a convex point, which indicates the existence of a trap for hydrocarbon accumulation, or a point on the boundary of the DEM, which suggests that the pathway of hydrocarbon migration extends outside the DEM. In addition, a concourse point of two paths is also considered as a termination point of either path. The algorithms were successfully applied in the modeling of the secondary migration pathways in the northern Songliao Basin, northeast China. The modeled results matched well with drilling data, suggesting the robustness of the algorithms. [Copyright &y& Elsevier]

Abstract: High-resolution sea surface temperatures (SST) derived from Mg/Ca ratios of Globeriginoides sacculifer at ODP Site 1144 were reported to reveal the SST changes during the last 260 ka in the northern South China Sea (SCS). The results indicate an average Holocene SST of about 26.7 °C, about 3.6 °C increase from LGM to the Holocene, and higher temperature during MIS 5.5 than the Holocene. These agree well with other foraminifer Mg/Ca and Uk 37 SST records in this region. The Mg/Ca records suggest warmer SSTs during MIS 3 in the northern SCS, compared with those in the eastern Pacific. Strong East Asian summer monsoon during MIS 3 indicated by paleoclimate records from nearby continents may account for it. Step-wise increases during terminations are shown in our SST record, and the beginning of deglacial warming occurs at about 19 ka, which precedes the change of oxygen isotopes, suggesting a tropical driven forcing for the SST change in the northern SCS. This is further supported by a robust semi-precessional cycle centering at ∼9.1 ka in the spectra of the SST record, which is absent in that of the oxygen isotopes. However, tropical driven forcing seems not to be indicated in another Mg/Ca SST record in the northern SCS [Oppo, D.W. and Sun, Y.B., 2005. Amplitude and timing of sea-surface temperature change in the northern South China Sea: Dynamic link to the East Asian monsoon. Geology, 33 (10): 785–788.]. The discrepancy may be caused by different post-deposition dissolutions of foraminifer tests at these two sites. Details about the modification of foraminifer Mg/Ca ratios after burial, however, are not well known in this region, and further studies are needed. [Copyright &y& Elsevier]

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., Competing Interests: Declaration of conflicting interestsThe author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article.

Purpose: The prognostic value of blood eosinophils in patients with acute exacerbation of chronic obstructive pulmonary disease (AECOPD) remains controversial. This study aimed to evaluate whether blood eosinophils could predict in-hospital mortality and other adverse outcomes in inpatients with AECOPD., Methods: The patients hospitalized for AECOPD were prospectively enrolled from ten medical centers in China. Peripheral blood eosinophils were detected on admission, and the patients were divided into eosinophilic and non-eosinophilic groups with 2% as the cutoff value. The primary outcome was all-cause in-hospital mortality., Results: A total of 12,831 AECOPD inpatients were included. The non-eosinophilic group was associated with higher in-hospital mortality than the eosinophilic group in the overall cohort (1.8% vs 0.7%, P < 0.001), the subgroup with pneumonia (2.3% vs 0.9%, P = 0.016) or with respiratory failure (2.2% vs 1.1%, P = 0.009), but not in the subgroup with ICU admission (8.4% vs 4.5%, P = 0.080). The lack of association still remained even after adjusting for confounding factors in subgroup with ICU admission. Being consistent across the overall cohort and all subgroups, non-eosinophilic AECOPD was also related to greater rates of invasive mechanical ventilation (4.3% vs 1.3%, P < 0.001), ICU admission (8.9% vs 4.2%, P < 0.001), and, unexpectedly, systemic corticosteroid usage (45.3% vs 31.7%, P < 0.001). Non-eosinophilic AECOPD was associated with longer hospital stay in the overall cohort and subgroup with respiratory failure (both P < 0.001) but not in those with pneumonia (P = 0.341) or ICU admission (P = 0.934)., Conclusion: Peripheral blood eosinophils on admission may be used as an effective biomarker to predict in-hospital mortality in most AECOPD inpatients, but not in patients admitted into ICU. Eosinophil-guided corticosteroid therapy should be further studied to better guide the administration of corticosteroids in clinical practice., Competing Interests: The authors report no conflicts of interest in this work., (© 2023 Pu et al.)