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Mucositis is a common and most debilitating complication associated with the cytotoxicity of chemotherapy. The condition affects the entire alimentary canal from the mouth to the anus and has a significant clinical and economic impact. Although oral and intestinal mucositis can occur concurrently in the same individual, these conditions are often studied independently using organ-specific models that do not mimic human disease. Hence, the purpose of this scoping review was to provide a comprehensive yet systematic overview of the animal models that are utilised in the study of chemotherapy-induced mucositis. A search of PubMed/MEDLINE and Scopus databases was conducted to identify all relevant studies. Multiple phases of filtering were conducted, including deduplication, title/abstract screening, full-text screening, and data extraction. Studies were reported according to the updated Preferred Reporting Items for Systematic reviews and Meta-Analyses Extension for Scoping Reviews (PRISMA-ScR) guidelines. An inter-rater reliability test was conducted using Cohen's Kappa score. After title, abstract, and full-text screening, 251 articles met the inclusion criteria. Seven articles investigated both chemotherapy-induced intestinal and oral mucositis, 198 articles investigated chemotherapy-induced intestinal mucositis, and 46 studies investigated chemotherapy-induced oral mucositis. Among a total of 205 articles on chemotherapy-induced intestinal mucositis, 103 utilised 5-fluorouracil, 34 irinotecan, 16 platinum-based drugs, 33 methotrexate, and 32 other chemotherapeutic agents. Thirteen articles reported the use of a combination of 5-fluorouracil, irinotecan, platinum-based drugs, or methotrexate to induce intestinal mucositis. Among a total of 53 articles on chemotherapy-induced oral mucositis, 50 utilised 5-fluorouracil, 2 irinotecan, 2 methotrexate, 1 topotecan and 1 with other chemotherapeutic drugs. Three articles used a combination of these drugs to induce oral mucositis. Various animal models such as mice, rats, hamsters, piglets, rabbits, and zebrafish were used. The chemotherapeutic agents were introduced at various dosages via three routes of administration. Animals were mainly mice and rats. Unlike intestinal mucositis, most oral mucositis models combined mechanical or chemical irritation with chemotherapy. In conclusion, this extensive assessment of the literature revealed that there was a large variation among studies that reproduce oral and intestinal mucositis in animals. To assist with the design of a suitable preclinical model of chemotherapy-induced alimentary tract mucositis, animal types, routes of administration, dosages, and types of drugs were reported in this study. Further research is required to define an optimal protocol that improves the translatability of findings to humans. [ABSTRACT FROM AUTHOR]

Disrupted endothelial permeability plays a crucial role in the vasculitis pathogenesis of Kawasaki disease (KD), which leads to pathological vascular leak and facilitates inflammatory cell infiltration in vascular lesions; however, the mechanisms involved in the development of endothelial barrier dysfunction during KD vasculitis are still largely unclear. Here, we found that sera from patients with KD can induce endothelial cell (EC) hyperpermeability compared to sera from healthy controls. We observed that serum vascular endothelial growth factor (VEGF) levels were increased in KD patients and sera from KD patients upregulated the expression of VEGF receptor 2 (VEGFR2) and neuropilin-1 (NRP1) in human coronary artery endothelial cells (HCAECs). Intriguingly, compared with silence of VEGFR2 in HCAECs, NRP1 silence resulted in a marked decrease in EC permeability. Furthermore, soluble NRP1 (sNRP1) remarkably reduced the stimulation of EC permeability by sera from KD patients compared with bevacizumab treatment. Importantly, we showed that besides VEGF, angiopoietin-like-4 (ANGPTL4), a NRP1-binding vasoactive factor, was also increased in KD and contributed to the EC permeability in KD conditions. In addition, levels of both ANGPTL4 and VEGF were inversely correlated with albumin levels in the serum of KD patients. Collectively, the data demonstrated that overexpressed NRP1, along with upregulated VEGFR2, in HCAECs treated with KD sera promotes endothelial permeability via interaction with the increased ANGPTL4 and VEGF in KD. Neutralization of hyperpermeability factors by sNRP1 may be a novel therapeutic strategy for KD vasculitis. [ABSTRACT FROM AUTHOR]

Inflammation of endothelial cells (ECs) plays an important role in the pathogenesis of coronary artery lesions (CALs) in Kawasaki disease (KD). Semaphorin 4D (Sema4D) is the first semaphorin shown to have immunoregulatory functions by interacting with its receptors—plexin Bs. Recently, Sema4D has been reported to exert a proinflammatory effect on the endothelium and to be involved in cardiovascular disease. However, the role of Sema4D in KD remains unknown. This study was aimed at revealing the change of soluble Sema4D (sSema4D) in the serum of patients with KD and the effect of the sSema4D-plexin axis on the production of proinflammatory cytokines from human coronary endothelial cells (HCAECs) stimulated with sera from KD patients. Our results showed that serum sSema4D levels were specifically elevated in KD patients, especially in those with CALs, and correlated positively with disease severity and serum concentrations of interleukin- (IL-) 1β, IL-6, and IL-8. The disintegrin and metalloproteinase domain 17- (AMAM17-) mediated Sema4D shedding from neutrophils contributed to the elevation of sSema4D in the serum of KD patients. Furthermore, we found that Sema4D induced IL-1β production of HCAECs via plexin B2, whereas it promoted IL-6 and IL-8 production via plexin B1. Moreover, the expression of both plexin B1 and plexin B2 was upregulated in HCAECs treated with KD sera, and silencing of the two plexin receptors suppressed the overexpression of IL-1β, IL-6, and IL-8 in KD serum-treated HCAECs. Thus, our findings indicated that sSema4D released from neutrophils participates in the pathogenesis of KD-CALs by promoting inflammatory cytokine production of ECs via both plexin B1 and plexin B2, and Sema4D may be a novel predictor for KD-CALs and a candidate therapeutic target for anti-inflammatory strategies of KD. [ABSTRACT FROM AUTHOR]

Highlights: A transparent, conductive, and flexible metal mesh film has been developed by a low-cost, uniform self-forming crackle template and electroplating strategy. The Cu mesh films show an ultra-low sheet resistance (0.18 Ω □−1), high transmittance (85.8%@550 nm), high figure of merit (> 13,000), excellent stretchability and mechanical stability. The metal mesh film can be used as a flexible heater and electromagnetic interference shielding film (40.4 dB at 2.5 μm). Despite the growing demand for transparent conductive films in smart and wearable electronics for electromagnetic interference (EMI) shielding, achieving a flexible EMI shielding film, while maintaining a high transmittance remains a significant challenge. Herein, a flexible, transparent, and conductive copper (Cu) metal mesh film for EMI shielding is fabricated by self-forming crackle template method and electroplating technique. The Cu mesh film shows an ultra-low sheet resistance (0.18 Ω □−1), high transmittance (85.8%@550 nm), and ultra-high figure of merit (> 13,000). It also has satisfactory stretchability and mechanical stability, with a resistance increases of only 1.3% after 1,000 bending cycles. As a stretchable heater (ε > 30%), the saturation temperature of the film can reach over 110 °C within 60 s at 1.00 V applied voltage. Moreover, the metal mesh film exhibits outstanding average EMI shielding effectiveness of 40.4 dB in the X-band at the thickness of 2.5 μm. As a demonstration, it is used as a transparent window for shielding the wireless communication electromagnetic waves. Therefore, the flexible and transparent conductive Cu mesh film proposed in this work provides a promising candidate for the next-generation EMI shielding applications. [ABSTRACT FROM AUTHOR]

In order to determine the role of defects (vacancies and extended lattice defects) in the conductivity mechanism of a well studied organic ionic plastic crystal electrolyte, conductivity and mean defect volumes were measured. The ionic conductivity of the salt showed a characteristic phase dependence. Defect volumes, as measured by positron annihilation lifetime spectroscopy, showed increasing rates of expansion with increasing rotational disorder. The dependence of ionic conductivity on defect volume was observed to be phase dependent. Increases in mean defect volume size below ≈100 cm3 mol-1 did not always facilitate ionic conductivity. It was shown that the material undergoes a solid-solid phase transition to the most disordered phase (a plastic crystalline phase with the highest conductivity) when the mean defect volume becomes larger than the molar volume of either the rotating anionic or cationic species. Conductivity in this phase had the strongest dependence on defect volume. Critical volumes calculated from the free volume model of Cohen and Turnbull were unrealistically large. [ABSTRACT FROM AUTHOR]

Highlights: • The PR passivation can be fabricated at a temperature of 100 °C. • The PR passivation exhibited excellent barrier ability against water and oxygen molecules. • The PR passivation protect the surface and change the element distribution of IGZO thin film. Abstract Bottom-gate InGaZnO (IGZO) thin-film transistors (TFTs) with EOC photoresist (PR) passivation were fabricated. Compared to the unpassivated IGZO TFT with a mobility of 6.71 cm2 V−1 s−1, a hysteresis of 2.42 V and a poor bias stress stability, the PR-passivated IGZO TFT showed good electrical characteristics with a higher mobility of 8.85 cm2 V−1 s−1, a lower hysteresis of 0.06 V and a more reliable stability (△ V th = 0.36 V) under positive gate bias stress (PBS). The effect of PR passivation on the performance of IGZO-TFT was investigated by x-ray photoelectron spectroscopy (XPS), systemically. The result of XPS spectra of the O 1s core levels indicate that PR passivation effectively suppressed the adsorption/desorption effect on IGZO surface, resulting in fewer unstable states and higher electrical stability. Furthermore, XPS depth profile experiments show that the proportion of elements on the film surface changed and the IGZO surface was In-rich after PR passivation, enhancing the mobility. The PR passivation with low temperature (100 °C) process exhibited good dielectric quality and excellent barrier ability against water and oxygen molecules. Therefore, it may be a good candidate for high-mobility and high-stability flexible TFTs in future. [ABSTRACT FROM AUTHOR]

In this paper, a tunable acid-resistant Zr-doped indium oxide (ZrInO) semiconductor material was developed. Detailed studies showed that the acid resistance of ZrInO thin films is tunable and increases with the increase in annealing temperature. Taking advantage of this special property, we successfully fabricated back-channel-etched (BCE) thin-film transistors (TFTs) based on the tunable acid-resistant ZrInO thin film. ZrInO-TFTs with BCE structure exhibited excellent electrical performance with a saturation mobility of 21.4 cm $^{\textsf {2}}\textsf {V}^{-\textsf {1}}\textsf {s}^{-\textsf {1}}$ , a subthreshold swing of 0.28 V/decade, and an ON/OFF current ratio of $1.0\times107$. These results envision that the developed ZrInO semiconductor with tunable acid resistance has a good prospect for the channel layer of BCE-TFTs. [ABSTRACT FROM AUTHOR]

The immune evasion of wild-type (wt) rabies virus (RABV) has been attributed to its glycoprotein (G), particularly to their inefficiency to bind/enter into dendritic cells (DCs). However, the domain responsible for G-mediated DC activation is not clear. In the present study, attempts were made to map the domain(s) on the G involved in differential DC activation using laboratory-adapted and wt viruses. Recombinant RABVs with exchange in each of the structural domains such as signal peptide (sp), ectodomain (et), transmembrane domain (tm), cytoplasmic tail (ct) of the G between wt and laboratory-adapted strains were constructed. Characterizations of these recombinant RABVs show that the viruses containing the sp, tm and ct from the wt G are capable of growing in high titer by efficient cell-to-cell spread, similar to laboratory-adapted virus. On the other hand, recombinant virus containing the et domain from wt G was inefficient in cell-to-cell spread and grew in lower levels, similar to the wt RABV. Analysis of DC activation shows that viruses containing sp and tm from wt G are efficient in binding to and activating DCs. However, viruses containing the et domain from wt G are incompetent in binding to and activating DCs. Analysis of the G expression in the infected cells suggests that the level of G expression is regulated solely by the ct domain, indicating the level of G expression and DC activation are governed by different domains. Together, our results demonstrate that G-mediated DC activation is regulated by the et domain while the level of G expression by the ct domain. [ABSTRACT FROM AUTHOR]

The ion pair structures of a novel CO 2 capture material in the form of a metal chelate anion-containing room temperature ionic liquid (IL), 1-ethyl-3-methylimidazolium tri[bis(trifluoromethylsulfonyl)imide]zincate(II), [Emim][Zn(TFSI) 3 ], were elucidated by correlating the infrared spectra generated using density functional theory (DFT) calculations with the experimental spectrum derived from a room temperature infrared spectroscopic measurement. A free volume energy minimization algorithm revealed stable structures where the zinc ion forms an octahedral, homoleptic complex with the ligand bis(trifluoromethylsulfonyl)imide through coordination with the oxygen of the sulfone group, with 1-ethyl-3-methylimidazolium acting as the counterion. The method of analysis was built around 1-ethyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide, [Emim][TFSI], involving direct comparison with published data, and extended to the more complex [Emim][Zn(TFSI) 3 ] system. The DFT calculations reproduced the vibrational spectra of [Emim][Zn(TFSI) 3 ] and [Emim][TFSI] using their optimized geometries, with correlation slopes of 0.9996 and 1.0022, respectively. Comparison of the vibrational modes of [Emim][TFSI] and [Emim][Zn(TFSI) 3 ] provided insights into the ion pair structure of, and molecular interactions in the ILs analyzed. [ABSTRACT FROM AUTHOR]

We developed porous silica supported zinc-functionalized IL sorbents prepared by confining a thin layer of IL onto the surface of SBA-15. This novel hybrid sorbent system exhibited unprecedented high uptake capacity of up to 4.7 mmol CO 2 g −1 sorbent, a dramatic enhancement compared to bulk IL (600%) and bare support (250%). Most remarkably, the rate of uptake was improved by up to 10 times, synergistically arising from the strong affinity of the IL to CO 2 , and the large surface area and high porosity of the support. [ABSTRACT FROM AUTHOR]

Abstract: Sinojackia is a Chinese endemic genus of Styracaceae, containing eight species. The taxonomy of one species, Sinojackia dolichocarpa (≡Changiostyrax dolichocarpa), is controversial. Here we investigate the distribution of leaf wax n-alkanes to clarify the chemotaxonomic position of S. dolichocarpa. Leaf samples of six Sinojackia species from Wuhan Botanical Garden in central China were collected during April, July, and December in 2010 to capture different developmental stages of the epicuticular waxes. Our results show that the waxes of S. dolichocarpa differ from the other five species by having a lower abundance of nC31 but a higher abundance of nC33. Although developmental variations of n-alkane distributions were observed during the sampling periods, cluster analysis based on the percentages of n-alkanes from C27 to C33 separates S. dolichocarpa from the other Sinojackia species. Based on these finding, we suggest S. dolichocarpa is a species independent of the Sinojackia genus. [Copyright &y& Elsevier]

Abstract: The free carrier generation processes at the interface formed by fullerene (C60) and perfluorinated hexadecafluorophthalo-cyaninatozinc (F16ZnPc) are investigated in detail. It is found that the exciton dissociation and recombination across the interface can happen at the same C60/F16ZnPc interface. And it is demonstrated in this study that both processes can be the dominant process for photocurrent generation by simply changing the direction of the built-in electric field. The observed superlinear dependence between photocurrent and light intensity confirms that the photocurrent indeed is the second order to the incident light intensity. Thus the photocurrent can be generated from the exciton recombination across the C60/F16ZnPc interface. [Copyright &y& Elsevier]

Conventional reverse genetics for classical swine fever virus (CSFV) is based on the transfection of permissive cells with either in vitro or intracellularly synthesized RNA transcripts from a viral genomic cDNA clone. These strategies are complicated, inefficient and time-consuming. This study is aimed to develop an improved reverse genetics method for the direct, rapid and efficient recovery of CSFV from cloned cDNA. The cDNA clone pBRCISM was constructed, which harbors the full-length genomic sequence from the CSFV Shimen strain flanked by the cytomegalovirus promoter (an RNA polymerase II promoter), a chimeric intron, and hammerhead ribozyme sequences at the 5′-end and the hepatitis delta virus ribozyme and SV40 polyadenylation signal sequences at the 3′-end. Infectious progeny virus was rescued from PK-15 cells directly transfected with pBRCISM, and its morphology, one-step growth characteristics and pathogenicity were indistinguishable from the parent virus and virus rescued from classical reverse genetics. The reverse genetics based on RNA polymerase II yielded a 120-fold increase in the titer of nascent virus in 12-h less time than a reverse genetics method based on in vitro transcription. The full-length cDNA clone remained stable and infectious after 20 passages in bacterial cells, in contrast to the instability of the full-length clone without the intron after 9 passages. The improved reverse genetics method developed in the present study is efficient, stable, convenient and cost-effective and will be valuable for the rapid recovery of CSFV mutants. [ABSTRACT FROM AUTHOR]

Abstract: By investigating the turn-on and turn-off photovoltage dynamics as a function of aging time, we reported the roles of traps on the energy loss in organic solar cells composing of copper phthalocyanine (CuPc)/fullerene (C60). Illuminating the device with square pulses of light, a peak of transient photovoltage after turn-on was observed after device degradation. After turn-off, the transient photovoltage first goes to the negative before settling back to zero, which is the result of electron trapping in the C60 layer before being neutralized by re-injected holes. Furthermore, by adding a tris (8-hydroxyquinolinato) aluminum buffer to prevent the traps from propagating into C60 layer, the peak after turn-on is greatly suppressed and the negative peak after turn-off vanishes, supporting the trapped electrons in the C60 layer play the critical role in the appearance of peak of the transient photovoltage. [Copyright &y& Elsevier]

The article focuses on a study which examined the mass extinction event in the Paleo-Tethys Ocean or the Kamura event. Samples of fresh carbonate were collected from the Shangsi and Laibin Sections in China. Results of the study showed variations in the carbon isotope composition in the Laibin Section. The study also found that the high positive plateau of carbon isotope during the Capitanian period did not occur in the Tethyan Ocean.

On the basis of GC and GC-MS analyses, the seasonal variation of leaf lipids is observed in five plant species in Qingjiang in Hubei Province. The CPI values (carbon preference index) of n-alkanes decrease gradually from May to November, though the carbon number distributions and the predominant carbon number in an individual species keep unchanged. The declined CPI values might be caused by the leaf fading, which is further supported by a comparison of the defoliated leaves with the fresh leaves. This observation infers the CPI values of n-alkanes in Quaternary sediments can be used as a tool to index the humification, and thus the climatic and the environmental conditions. The plants analyzed here show a remarkable difference in n-alkanes abundance, suggesting their differential contribution to the n-alkanes identified in sediments. The abundance and the compound species of the n-alkenes detected in the plant leaves change greatly with the seasons due to the influence of temperature, with the least compounds being identified in August. [ABSTRACT FROM AUTHOR]

Abstract: This paper describes the relationship between the ionic conduction and the characteristics of defects in plastic crystalline phases of N,N-dimethylpyrrolidinium bis(trifluoromethanesulfonyl)amide (P11TFSA). Positron annihilation lifetime spectroscopy (PALS) shows that the phase III to phase II transition involves the generation and expansion of vacancies, which is confirmed by measurement of volumetric expansion. The vacancies expand to match the cation size in phase II and this gives rise to an increase in the conductivity. The relationship between the vacancy volume and the conductivity obeys a Cohen–Turnbull free volume conduction model. The critical volume matches the volume of a cation–anion pair in phase III, which indicates a Schottky mechanism. The critical volume shows a greater value in phase II, which is probably indicative of a pipe diffusion mechanism. [Copyright &y& Elsevier]

Abstract: Despite considerable work on other trace elements, the incorporation of dissolved silicon from cave waters into speleothems has not been previously investigated. In this study, the controls on dissolved Si in cave waters and on adsorbed Si in resulting speleothems are therefore investigated. Bedrock (dolomite), soil water, dripping water, and cave carbonates were retrieved from Heshang Cave situated in the central Yangtze valley of China and were subjected to analysis of dissolved Si content (plus accompanying Ca and Fe analyses). Soil waters have Si/Ca of 45.5 mmol/mol, compared to only 3.2 mmol/mol in the dolomite bedrock, demonstrating that >80% of the dissolved Si must come from dissolution of silicate minerals in the soil. Drip waters have a dissolved Si concentration of ¿4.2 µg/mL, similar to that in the overlying soil water. Actively growing cave carbonates have a Si/Ca of 0.075 mmol/mol suggesting a partition coefficient for incorporation of dissolved silicon of 0.0014, in good agreement with previous laboratory studies. Extrapolating the results of these laboratory studies to the cave environment suggests that changes in Si/Ca in cave carbonates are likely to be primarily controlled by changes in drip-water Si/Ca. The drip-water Si/Ca will, in turn, be controlled by the rate of wind-blown silicate supply; by soil weathering rates; by rainfall dilution; and by precipitation of calcite. The general expectation is that these effects combine to produce high Si/Ca in speleothems during times of low rainfall. A d18O record from a Heshang Cave stalagmite which grew between 20 and 11 thousand years ago allows these controls to be tested. Correlation of high Si/Ca with high d18O demonstrates that regional rainfall exerts significant (but not complete) control on speleothem Si/Ca. With further understanding, speleothem Si/Ca may provide a proxy for past rainfall to complement existing proxies such as d18O and Mg/Ca. [Copyright &y& Elsevier]

Objective: To explore the relationship between gestational weight gain (GWG) and birth weight outcomes and establish suggested GWG patterns in early pregnancy weight loss women. Methods: This retrospective study was conducted based on the Beijing Birth Cohort Study from 2014 to 2021 and included 20 688 women. Weight change in early pregnancy was calculated using weight measurements within 16 weeks of gestation. Multivariable logistic regression was used to analyze the relationships of different GWG categories, based on the Chinese standard, and birth weight outcomes. The statistical‐based approach was used to determine the optimal GWG ranges and weekly weight gain. Results: Compared to 3313 women who gained appropriate weight in early pregnancy, 2614 women who lost weight in the same period increased the risk of small for gestational age (SGA) (OR = 1.43, 95% CI: 1.14–1.80, P = 0.002). However, the relationship disappeared after adjusting for total GWG. Among the early pregnancy weight loss women, both excessive GWG and inadequate GWG were associated with adverse birth weight outcomes after adjusting for confounders. The suggested GWG range and rate were 11.0 ~ 16.0 kg and 0.46 to 0.67 kg/week from 16 weeks to delivery for women with normal body mass index (BMI) and weight loss in early pregnancy. Conclusion: Weight loss in early pregnancy was not the independent risk factor of birth weight outcomes. GWG may offset the expected effects. To achieve optimal outcomes, women with normal BMI and weight loss in early pregnancy need to have a higher weight gain rate in mid‐late pregnancy but similar total GWG ranges with the Chinese standard for general women. Synopsis: The subsequent weight gain and total gestational weight gain are associated with birth weight outcomes in early pregnancy weight loss women. [ABSTRACT FROM AUTHOR]

Highlights: A stretchable, transparent, and ultra-broadband (0.1–10 THz) terahertz shielding MXene (Ti3C2Tx) film has been fabricated by a structure engineering strategy. Theoretical calculations indicate that the wrinkled structure enhances the film's conductivity and surface plasmon resonances, resulting in an improved THz wave absorption. The wrinkled MXene films exhibit superb conformability to surfaces with random curvatures, and can be used as a shielding film for THz imaging. With the increasing demand for terahertz (THz) technology in security inspection, medical imaging, and flexible electronics, there is a significant need for stretchable and transparent THz electromagnetic interference (EMI) shielding materials. Existing EMI shielding materials, like opaque metals and carbon-based films, face challenges in achieving both high transparency and high shielding efficiency (SE). Here, a wrinkled structure strategy was proposed to construct ultra-thin, stretchable, and transparent terahertz shielding MXene films, which possesses both isotropous wrinkles (height about 50 nm) and periodic wrinkles (height about 500 nm). Compared to flat film, the wrinkled MXene film (8 nm) demonstrates a remarkable 36.5% increase in SE within the THz band. The wrinkled MXene film exhibits an EMI SE of 21.1 dB at the thickness of 100 nm, and an average EMI SE/t of 700 dB μm−1 over the 0.1–10 THz. Theoretical calculations suggest that the wrinkled structure enhances the film's conductivity and surface plasmon resonances, resulting in an improved THz wave absorption. Additionally, the wrinkled structure enhances the MXene films' stretchability and stability. After bending and stretching (at 30% strain) cycles, the average THz transmittance of the wrinkled film is only 0.5% and 2.4%, respectively. The outstanding performances of the wrinkled MXene film make it a promising THz electromagnetic shielding materials for future smart windows and wearable electronics. [ABSTRACT FROM AUTHOR]

The Beijing Birth Cohort Study (BBCS) is a research project that aims to investigate the effects of health conditions during pregnancy on the development of offspring. The study collected data from over 52,000 pregnant women in Beijing between 2017 and 2021. The study found that a significant percentage of women had abnormal pre-pregnancy body mass indexes (BMI) and experienced conditions such as gestational diabetes mellitus (GDM), thyroid disease, and hypertensive disorders of pregnancy. The study also examined delivery modes and fetal abnormalities. The BBCS has strengths such as comprehensive sample collection and the ability to study the impact of COVID-19, but a weakness is that it was established at a single center. The data are not yet openly available, but researchers can contact the investigators for potential collaboration. The study was approved by the Ethics Committee of Beijing Obstetrics and Gynecology Hospital and was supported by the National Key Research and Development Program of China. [Extracted from the article]

Elaeagnus L. (Elaeagnaceae) is an important plant genus widely used in erosion control due to its high wind breaking and soil binding capacity, but also possessing medicinal and ornamental values. The phenotypic similarity of fruits and flowers of E. moorcroftii and E. angustifolia has often led researchers to speculate on their close relationship and they have sometimes been considered conspecific. In this study, 16 morphological characters were selected and assigned for cluster analysis which divided the samples (n = 49) into six groups: three of E. moorcroftii and three of E. angustifolia. Simple‐sequence repeat (SSR) markers were used to discern the genetic diversity of the 49 individuals. Genetic diversity was found to be high (He = 288, I = 0.938) and there was a strong correlation between the morphological and SSR data. Thus, when combined, the phenotypic classification and SSR marker based evidence confirmed E. moorcroftii as a distinct species independent from E. angustifolia, a conclusion not in agreement with the treatment in recent floras. [ABSTRACT FROM AUTHOR]

Tandem white organic light-emitting diodes (WOLEDs) are promising for the lighting and displays field since their current efficiency, external quantum efficiency and lifetime can be strikingly enhanced compared with single-unit devices. In this invited review, we have firstly described fundamental concepts of tandem device architectures and their use in WOLEDs. Then, we have summarized the state-of-the-art strategies to achieve high-performance tandem WOLEDs in recent years. Specifically, we have highlighted the developments in the four types of tandem WOLEDs (i.e., tandem fluorescent WOLEDs, tandem phosphorescent WOLEDs, tandem thermally activated delayed fluorescent WOLEDs, and tandem hybrid WOLEDs). Furthermore, we have introduced doping-free tandem WOLEDs. In the end, we have given an outlook for the future development of tandem WOLEDs. [ABSTRACT FROM AUTHOR]

Since 2014, nanoplatelet light-emitting diodes (NPL-LEDs) have been emerged as a new kind of LEDs. At first, NPL-LEDs are mainly realized by CdSe based NPLs. Since 2016, hybrid organic-inorganic perovskite NPLs are found to be effective to develop NPL-LEDs. In 2017, all-inorganic perovskite NPLs are also demonstrated for NPL-LEDs. Therefore, the development of NPL-LEDs is flourishing. In this review, the fundamental concepts of NPL-LEDs are first introduced, then the main approaches to realize NPL-LEDs are summarized and the recent progress of representative NPL-LEDs is highlighted, finally the challenges and opportunities for NPL-LEDs are presented. [ABSTRACT FROM AUTHOR]

Background: Parental exposure to rare earth elements (REEs) could increase the risk of premature rupture of membranes, a major cause of spontaneous preterm birth (SPB). In addition, different subtypes of SPB, such as spontaneous preterm labor (SPL) and preterm premature rupture of membranes (PPROM), may have different susceptibility to environmental exposure. Therefore, we investigated the potential associations between REE exposure in different trimesters and SPB and its subtypes. Methods: A nested case-control study was performed. We included 244 women with SPB as cases and 244 women with full-term delivery as controls. The plasma concentrations of light REEs were measured in the first and third trimesters. Logistic regression was used to analyze the associations between single REE levels and SPB, and Bayesian kernel machine regression (BKMR) was used to analyze the mixed-exposure effect. Results: Exposure to light REEs was associated with SPB and its subtypes only in the third trimester. Specifically, the intermediate- and highest-tertile concentration groups of La and the highest-tertile concentration group of Sm were associated with an increased risk of SPL, with adjusted odds ratios (AORs) of 2.00 (95% CIs: 1.07–3.75), 1.87 (95% CIs: 1.01–3.44), and 1.82 (95% CIs: 1.00–3.30), respectively. The highest-tertile concentration group of Pr was associated with an increased risk of PPROM, with an AOR of 1.69 (95% CIs: 1.00–2.85). Similar results were also found in BKMR models. Conclusions: La and Sm levels in plasma may be associated with the risk of SPL, and Pr levels in plasma may be associated with the risk of PPROM. [ABSTRACT FROM AUTHOR]

The common walnut (Juglans regia L.), a species of significant economic and ecological importance, along with its variant, holds developmental value. Simple sequence repeat (SSR) markers are used as an effective method for material identification due to their co-dominant inheritance. In this work, a total of 357629 SSR loci were searched based on previously published walnut genome sequences, with a density of 662.28 (SSRs/Mb). The majority of all these loci were found to be single nucleotide A/T (58.49%), followed by the dinucleotide AT (19.48%). Based on the results of genome-wide SSR site design, 22 effective primer pairs were designed and screened to analyze the genetic diversity of 48 wild walnut samples from three countries. Each locus had an average of 5.17 effective alleles (Ne), with an average polymorphism information content (PIC) of 0.71, average heterozygosity (He) of 0.52, and average genetic differentiation index (Fst) of 0.09. The analysis of 48 wild walnut samples from three countries (Kyrgyzstan, Tajikistan, and China) using the unweighted pairwise clustering method and arithmetic mean (UPGMA) along with principal coordinate analysis revealed the division of all samples into three groups. In summary, these novel SSR markers serve as a reference for the identification of wild walnut germplasm in Central Asia and for the development and utilization of wild walnut seed resources. [ABSTRACT FROM AUTHOR]

For the first time, compounds with lanthanum from the main family element Boron (LaBx) were investigated as an active layer for thin-film transistors (TFTs). Detailed studies showed that the room-temperature fabricated LaBx thin film was in the crystalline state with a relatively narrow optical band gap of 2.28 eV. The atom ration of La/B was related to the working pressure during the sputtering process and the atom ration of La/B increased with the increase of the working pressure, which will result in the freer electrons in the LaBx thin film. LaBx-TFT without any intentionally annealing steps exhibited a saturation mobility of 0.44 cm2·V−1·s−1, which is a subthreshold swing (SS) of 0.26 V/decade and a Ion/Ioff ratio larger than 104. The room-temperature process is attractive for its compatibility with almost all kinds of flexible substrates and the LaBx semiconductor may be a new choice for the channel materials in TFTs. [ABSTRACT FROM AUTHOR]

The article discusses the research study conducted to examine the geological features and genesis of Scheelite Deposit in Pingtan, Chengbu County, Hunan Province, China. Topics discussed include exposure of magmatic rock, stratum, and ore structure, genesis of mineral deposits and tectonic fracture zone, and metasomatic deposit.

• Accidents in constructions and decorations were most prominent in work-related falls. • The work-related fatal fall rate was about 4.1 per 100,000 construction workers. • Young children aged 1–4 years had high risks of non-work-related fatal falls. In China, despite annually fall accidents caused more than 80,000 deaths, studies on occupational falls were scarce. The aim of this study is to investigate into work-related and non-work-related fatal falls in two major cities, Shanghai and Wuhan, China. The police records of accident fatal falls in Shanghai (2004–2017) and Wuhan (2009–2014) were used. Poisson regression was used to show the rate ratios related to city, gender, age, occupation, and height of the falls. Chi-square test was used to examine the demographic differences between the two cities. The annual fall mortality rates (per 100,000) were 0.35 and 0.49 in Shanghai and Wuhan, respectively. Work-related and non-work-related falls shared about equal proportion (rate ratio: 0.99). The demographics of work-related falls were similar in the two cities. Work-related falls were much more likely to occur in the males than in the females (Shanghai 88:2, Wuhan 76:3). Real estate constructions and household decoration accidents accounted for most work-related falls (Shanghai 55/90, Wuhan 66/79). In China, each year, construction-related fall mortalities could exceed 2000. These rates are similar to the USA and they are much higher than the official figures. Thus, safety measures for construction workers and household decoration workers should be improved, particularly for those self-employed workers and workers affiliated to small companies. Some compulsory safety course might also be needed to raise the safety awareness among these workers as well. Moreover, improving the safety of young children should be another area to prioritize in injury prevention. [ABSTRACT FROM AUTHOR]

Background: Abnormal lipid metabolism is associated with gestational diabetes mellitus (GDM) in singleton pregnancies. Data were lacking on twin pregnancies with GDM. We explored the association between serum lipid profiles in the first and second trimesters as well as their dynamic changes and GDM in twin pregnancies. Methods: This was a retrospective cohort study of 2739 twin pregnancies that underwent a 75-g oral glucose tolerance test (OGTT) and were selected from the Beijing Birth Cohort Study from June 2013 to May 2021. Cholesterol (CHO), triglyceride (TG), high-density lipoprotein (HDL) and low-density lipoprotein (LDL) levels were measured at mean 9 and 25 weeks of gestation. We described maternal lipid levels in different tertiles that were associated with the risk of GDM stratified for age, pre-BMI, and fertilization type. GDM patients were divided into two groups according to OGTT: elevated fasting plasma glucose only (FPG group) and the rest of the GDM (non-FPG group). We estimated the relative risk of GDM with multivariable logistic regression models. Results: In this study, we found that 599 (21.9%, 599/2739) twin pregnancies developed GDM. They had increased CHO, TG, LDL, and LDL/HDL, decreased HDL levels in the first trimester, and increased TG as well as decreased HDL in the second trimester in univariate analyses, each P < 0.05. In multivariate analysis, when TG > 1.67 mmol/l (upper tertile) in elderly individuals, nonoverweight and ART groups increased the risk of GDM by 2.7-fold, 2.3-fold and 2.2-fold, respectively, compared with TG < 0.96 mmol/l (lower tertile). This effect remained in the abovementioned groups in the second trimester. Moreover, high TGs increased the risk of GDM in the FPG group (OR = 2.076, 95% CI 1.130–3.815) and non-FPG group (OR = 2.526, 95% CI 1.739–3.67) in the first trimester when TG > 1.67 mmol/l, and the rising risk in the non-FPG group as the TG tertile increased remained in the second trimester. HDL predominantly showed a negative association with elevated FPG in the second trimester (p < 0.05). Conclusions: Twin pregnancies with GDM have higher lipid levels. Increased TGs in the first and second trimesters are strongly associated with GDM, especially in elderly individuals, nonoverweight and ART groups. Lipid profiles varied among different GDM subtypes. [ABSTRACT FROM AUTHOR]

OBJECTIVE: Breast cancer is a common malignancy in women and long non-coding RNAs (lncRNAs) have been shown to play key roles in the development and progression of breast cancer. In the present study, we examined the biological role of lncRNA gastric carcinoma highly expressed transcript 1 (GHET1) in breast cancer. METHODS: The expression of GHET1 was determined by qRT-PCR assay; CCK-8, colony formation, Transwell invasion and migration assays detected breast cancer cell proliferation, invasion and migration; cell apoptosis and cell cycle were determined by flow cytometry; protein levels were determined by western blot assay. RESULTS: GHET1 was up-regulated in breast cancer tissues and cell lines, and the up-regulation of GHET1 was positively correlated with larger tumor size, advanced clinical stage, lymph node metastasis and shorter overall survival. Knockdown of GHET1 suppressed cell proliferation, invasion and migration, and induced apoptosis and G 0 /G 1 cell cycle arrest in MCF-cells. Knockdown of GHET1 also suppressed the protein levels of N-cadherin, vimentin, and decreased the protein level of E-cadherin in MCF-7 cells. On the other hand, overexpression of GHET1 promoted cell proliferation, invasion and migration, and inhibited cell apoptosis and increased cell population at S phase in BT-20 cells. Overexpression of GHET1 also promoted epithelial mesenchymal transition (EMT) in BT-20 cells. Furthermore, knockdown of GHET1 also suppressed in vivo tumor growth of MCF-7 cells, and also decreased the protein levels of N-cadherin and vimentin, and increased the protein levels of E-cadherin in the tumor tissues from the nude mice. CONCLUSIONS: Our results demonstrated that GHET1 was up-regulated in breast cancer tissues and cell lines, and promoted breast cancer cell proliferation, invasion and migration by affecting EMT. Our study for the first time revealed the biological functions of GHET1 in breast cancer. [ABSTRACT FROM AUTHOR]

The CO 2 separation performance in ionic liquids modified porous silica gels prepared by the impregnation and grafting methods were investigated. The effects of impregnation amount and pore size distribution of adsorbents with different types of ionic liquids on the CO 2 /N 2 selectivity and water vapour adsorption and diffusion coefficient were analyzed in detail. The porous structures were characterized by CO 2 adsorption isotherms at 0 °C. Adsorption behavior of CO 2 (at 25, 40 and 60 °C) and N 2 (at 40 °C) was measured using a gravimetric method. Compared with the impregnated samples, the grafting of ILs on the support surface only causes a weak loss of microporosity, leading to a slight decrease in CO 2 adsorption capacity, and has much better recycling. CO 2 /N 2 selectivity and water resistance are however enhanced, especially samples with the longer chain on imidazolium cation. A conventional homogeneous surface diffusion model for ILs grafted silica was used to estimate the diffusivities and good agreement between experimental values and fitting curves were obtained. For ILs modified silica prepared with impregnation method, the CO 2 diffusivity constants include diffusion coefficients in ionic liquid phase and silica phase simultaneously. The diffusion coefficients are at a level of 10 −7 -10 −9 m 2 s −1 and about two or three orders of magnitude higher than that of neat ILs. The grafted silica exhibits diffusivities faster than those of the impregnated silica, indicating that more ionic liquids accessed into inner pore is unfavorable for CO 2 diffusion. [ABSTRACT FROM AUTHOR]

Two types of polymeric ionic liquids (PILs) modified porous silica for CO2 sorption were synthesized by the polymerization of dialkylphosphate di-butyl phosphate [VYIM][Bu2PO4] and 1-allyl-3-methylimidazolium tetrafluoroborate [AMIM][BF4] with alkoxyl-modified silica. The PILs-modified silica (SiO2-P[VYIM][Bu2PO4] and SiO2-P[AMIM][BF4]) were evaluated by CO2 adsorption isotherms at 273 K for investigating the porous structures. The adsorption and desorption behaviors of CO2 (at 298, 313, and 333 K) and N2 (at 313 K) up to 0.2 MPa were also investigated using a gravimetric method. In comparison with bare silica, the grafting of PILs on the support surface leads to a loss of microporosity, resulting in a slight decrease in CO2 sorption capacity. The difference of CO2 sorption capacity between SiO2-P[VYIM][Bu2PO4] and SiO2-P[AMIM][BF4] is little, especially under 0.1 MPa. CO2/N2 selectivity is however notably improved, and especially [AMIM][BF4] modified silica shows the best performance. The homogeneous surface diffusion model (HSDM) was used to estimate the diffusivities and good agreement between experimental values and fitting curves was obtained. The diffusion coefficients of CO2 in the PILs-modified silica are level with that of bare silica at level of 10−7−10−8 m2/s, about two to three orders of magnitude faster than that of reported [BMIM][BF4]. POLYM. COMPOS., 38:759-766, 2017. © 2015 Society of Plastics Engineers [ABSTRACT FROM AUTHOR]

Previous research has shown a strong persistence for direct teleconnections between the East Asian summer monsoon (EASM) and high northern latitude climate variability during the last glacial and deglaciation, in particular between monsoon weakening and a reduced Atlantic meridional overturning circulation (AMOC). However, less attention has been paid to EASM strengthening as the AMOC was reinvigorated following peak Northern Hemisphere (NH) cooling. Moreover, climate model simulations have suggested a strong role for Antarctic meltwater discharge in modulating northward heat transport and hence NH warming, yet the degree to which Southern Hemisphere (SH) climate anomalies impacted the Asian monsoon region is still unclear. Here we present a new stalagmite oxygen-isotope record from the EASM affected region of central China, which documents two prominent stages of increased 18 O-depleted moisture delivery to the region through the transition from Heinrich Stadial 1 (HS1) to the Bølling–Allerød (B–A) interstadial; this is in general agreement with the other monsoonal records from both NH and SH mid to low latitudes. Through novel comparisons with a recent iceberg-rafted debris (IRD) record from the Southern Ocean, we propose that the two-stage EASM intensification observed in our speleothem records were linked with two massive Antarctic icesheet discharge (AID) events at ∼16.0 ka and ∼14.7 ka, immediately following the peak HS1 stadial event. Notably, the large increase in EASM intensity at the beginning of the HS1/B–A transition (∼16 ka) is relatively muted in the NH higher latitudes, and better aligns with the changes observed in the SH, indicating the Antarctic and Southern Ocean perturbations could have an active role in driving the initial EASM strengthening at this time. Indeed, Antarctic freshwater input to the Southern Ocean during these AID events would have cooled the surrounding surface waters and caused an expansion of sea ice, restricting the southern extent of the SH westerlies. Moreover, increased meltwater flux during IRD events would have freshened Antarctic Intermediate Water, leading to the increased formation of North Atlantic Deep Water and enhanced North Atlantic subsurface heat release, and causing a strengthening of the AMOC during the HS1-Bølling transition. The result of this sequence-of-events would have been warming in the North Atlantic whilst at the same time cooling in the Antarctic. The ensuing interhemispheric temperature gradient would have acted to push the ITCZ northward, weakening the Australian–Indonesian summer monsoon (AISM) whilst intensifying the EASM. [ABSTRACT FROM AUTHOR]

When a C60-based device with the structure indium tin oxide (ITO)/N, N′-di-[(1-naphthyl)-N, N′-diphenyl]-1,1′-biphenyl)-4,4′-diamine (NPB)/fullerene (C60)/tris-(8-hydroxyquinoline) aluminium (Alq3)/aluminium (Al) is treated as a p-type sensitized solar cell, some methods for improving charge transportation and suppressing charge backflow in dye-sensitized solar cells can be applied to increase the performance of the C60 device. In this study, a 5 nm layer of molybdenum oxide (MoO3) is inserted between ITO and NPB to realize this idea. This thin layer with higher mobility and higher dielectric constant than NPB forms a cascade energy alignment with NPB, improving hole injection from C60 into NPB and hole transportation from NPB to ITO. The power conversion efficiency (PCE) of the C60-based device with MoO3 is enhanced to 0.976%, which is 3.92 times that of the device without MoO3. When MoO3 is replaced by copper phthalocyanine or rubrene, which has higher mobility than NPB and forms a cascade energy structure with NPB, the PCE of C60-based devices is improved to 0.539% and 0.529% respectively, which is 2.16 and 2.12 times that of devices without such treatments. [ABSTRACT FROM AUTHOR]

Novel high capacity hybrid sorbents for CO 2 capture have been developed based on zinc-functionalized ionic liquid (IL) impregnated into mesoporous silica beads derived from calcium alginate template beads. Pore modification and development of a surface-confined layer of IL synergistically enhanced the uptake capacity (up to 8.7 wt%) and kinetics of these materials. Spectroscopic and thermophysical signatures of the IL impregnated materials confirm the existence of a highly confined IL layer at low IL:SiO 2 ratio, and multilayer-mimicking bulk phase at higher IL loading. Our results clearly demonstrate that developing a thin layer of zinc-functionalized IL onto porous silica beads effectively enhances the uptake kinetics by exposing interaction sites across a large surface area, and facilitating diffusion through the pore network of the support. [ABSTRACT FROM AUTHOR]

Flexible strain sensors have enormous application demands in health monitoring, soft robotics, and artificial skin. Traditional flexible strain sensors mainly focus on identifying strain amplitude. However, to determine complex movements, it is necessary for sensors to recognize not only the amplitude but also the direction of strain. Here, we propose a multi-directional strain sensor constructed from three flexible strain sensor units, which are based on a carbon nanotube (CNT) array, and configured in a right-angled triangle arrangement. Each strain sensor unit exhibited a strain detection range of over 90%, durability of over 5000 cycles, and fast response time (<150 ms). The multi-directional strain sensor can accurately identify the amplitude and direction (up to 180°) of the strain simultaneously. By optimizing the height and the size of the CNT array strips within the strain sensor unit, the preferred parameters for the sensor unit were determined. Further, by incorporating a neural network algorithm, the multi-directional strain sensor achieved synchronous detection of strain amplitude and direction with an accuracy rate exceeding 98%. Therefore, this work provides a new strategy for the design and construction of multi-directional strain sensors, underscoring their broad application potential in the fields of human motion monitoring and gesture recognition. [Display omitted] [ABSTRACT FROM AUTHOR]

[Display omitted] [ABSTRACT FROM AUTHOR]

Multiple-sulfur isotope compositions ( 32 S, 33 S, 34 S and 36 S) were analyzed for paired carbonate-associated sulfate (CAS) and disseminated pyrite (PY) from the ∼1.6-Ga Gaoyuzhuang Formation of the North China Craton to reconstruct the history of sulfate levels in Proterozoic oceans. The 200-m-thick study interval yielded relatively constant values for δ 34 S CAS (13.0 ± 1.8‰), δ 34 S PY (8.0 ± 2.3‰), and Δ 34 S CAS-PY (∼5‰), as well as relatively constant Δ 33 S (0 ± 0.05‰) and Δ 36 S (0.35 ± 0.15‰) for both CAS and pyrite. Limited variation in δ 34 S PY and slightly lower Δ 33 S of pyrite relative to CAS suggest water-column precipitation of pyrite. Limited fractionation of sulfur during microbial sulfate reduction (as documented by Δ 34 S CAS-PY ) implies low seawater sulfate concentrations in the early Mesoproterozoic ocean. We quantitatively constrained paleo-seawater [SO 4 2− ] using a novel modeling approach based on measured values of Δ 34 S CAS-PY and ∂ δ 34 S CAS /∂ t (max). For the study unit, Δ 34 S CAS-PY is 5.4 ± 1.4‰ ( n = 17), and ∂ δ 34 S CAS /∂ t (max) is 6.8–34‰ Myr −1 based on sedimentation rates of 30–150 m Myr −1 . These data indicate early Mesoproterozoic seawater [SO 4 2− ] of ∼<0.1 to 0.35 mM (with a maximum possible concentration of 1.8 mM), a range that is lower and more tightly constrained than earlier estimates for the Mesoproterozoic. Compilation of published data suggests that low seawater sulfate concentrations began about ∼1.7 Ga and persisted until at least the mid-Mesoproterozoic (∼1.4 Ga), documenting a distinct early Mesoproterozoic perturbation in ocean chemistry that may have been related to a decline in atmospheric p O 2 after Great Oxidation Event I. [ABSTRACT FROM AUTHOR]

Organic matter preserved in speleothems has the potential to reflect the changes of the overlying vegetation and soil ecosystem. Here we report the first near 50-yr-resolution acid-soluble organic matter (ASOM) carbon isotope (δ 13 C ASOM ) sequence derived from a laminated stalagmite (HS-4) spanning the last 9 ky in Heshang Cave, central China. The δ 13 C ASOM values vary between − 25.8‰ and − 22.0‰, with lower values from 9 to 4 ka BP and less negative values from 4 to 0 ka BP. We postulate that the δ 13 C ASOM sequence is mainly controlled by temperature and water balance. Temperature could affect both vegetation physiology and microbial degradation in soil horizons. The influence of temperature on the δ 13 C ASOM is supported by the negative correlation ( r = − 0.48, p < 0.001) between the δ 13 C ASOM record and the paleotemperature record in the nearby Dajiuhu peatland. The water balance can affect the retention time of organic matter in soils. Under drier conditions, the soil organic matter will be retained longer and is more likely to be biologically degraded, resulting in more negative δ 13 C ASOM values. Our results reveal that δ 13 C ASOM in speleothems has the potential to reflect the response of vegetation and/or soil processes to paleoclimate changes. [ABSTRACT FROM AUTHOR]

Highlights: [•] For IL modified silica, CO2 adsorption depends on the porous nature of the silica. [•] The IL phases act as a selecting film which notably improves CO2/N2 selectivity. [•] The grafting method provides a good IL retention with gas cycling. [•] Diffusion coefficient in modified silica is in range of 10−8–10−7 m2/s using HSDM. [ABSTRACT FROM AUTHOR]

Abstract: The global carbon cycle experienced a major perturbation during the Permian–Triassic transition, reflected inter alia in a large increase in the vertical (shallow-to-deep) gradient of carbonate δ13C (Δ13Ccarb) in Early Triassic seas. However, the effect of this perturbation on the vertical gradient of organic matter δ13C in seawater (Δ13Corg) is less known to date. Here, we examine geographic and secular variations in Δ13Corg in Late Permian–Early Triassic seas of the South China craton and their implications for contemporaneous changes in microbial community composition and paleoredox conditions. Vertical δ13Corg gradients document the existence of a narrow and relatively shallow oxygen-minimum zone (OMZ) within the open-ocean Northern Deepwater Basin (NDW) and a deeper and thicker OMZ within the semi-restricted Nanpanjiang Basin (NPJB). For the pre-extinction interval, Δ13Corg gradients between the shallow and intermediate watermasses of the NDB and between the shallow and deep watermasses of the NPJB record contributions to the sediment of organic matter from bacteria living below the ocean-surface layer. These bacteria were mainly anaerobic chemoautotrophs that inhabited suboxic to anoxic waters of an OMZ and that produced more strongly 13C-depleted organic matter than surface-water eukaryotic algae, thus increasing Δ13Corg. For the post-extinction interval, a reversed Δ13Corg in the NDB is attributed to blooms of green sulfur bacteria or other anaerobic photoautotrophic bacteria that were resident in a deep chlorophyll maximum layer and that had smaller carbon isotopic fractionation than surface-water algae. Although quantitatively important in intermediate- to deep-water areas during the Early Triassic, such bacteria were absent in coeval shallow-water sections, reflecting water-depth controls on microbial community composition. A concurrent flatting of the Δ13Corg gradient in the NPJB was caused by a return of oxic conditions and/or a decline of primary productivity in the surface ocean. [Copyright &y& Elsevier]

This paper investigates the high-solution of Mo isotopes and uses trace-element analyses for fresh and representative black shales and siliceous shales collected from the transition between the Late Ordovician and the Early Silurian at the Wangjiawan section in Yichang and the Late Permian Dalong Formation in the Shangsi Section of Sichuan. The applicability of different geochemical parameters used as paleo-oxygenation indices are also compared. The preliminary results show that V/(V+Ni), U (auth U), V/Cr, Ce and U/Th have a scattered variation range, but most samples plot within the suboxic-anoxic fields. The suboxic-anoxic environment was dominant during the deposition and formation of the two anoxic facies. These redox indicators show little correspondence to the δMo values. The U/Mo ratio can be used as a potential proxy for the paleo-redox conditions due to the possibility that Mo is enriched relative to U at different redox gradients during early diagenesis. This evidence is more significant for the euxinicity condition and corresponds to positive δMo (>1.5‰) values with low U/Mo ratios. This evidence is likely related to the depositional conditions near the boundary between anoxic and euxinic environments, which are characterised by low bioturbation or water circulation. Other samples reveal a wide scatter of U/Mo ratios and δMo <1.5‰. These results are likely due to punctuated improvements in oxygenation with intense bioturbation or water circulation, which led to the redistribution of trace element. [ABSTRACT FROM AUTHOR]

Abstract: In order to investigate how lipids in cave water respond to seasonal climate change, drip water samples were collected from 2006 to 2008 in Heshang Cave, central China for fatty acid analysis. These lipids are abundant in the drip water. Their compositions are dominated by lower-molecular-weight nC16:0, nC18:0 and nC14:0 acids, together with mono-unsaturated nC18:1, nC16:1 and nC14:1. Analysis of one water sample revealed marked differences between the dissolved and particulate fractions. The dissolved fraction contains total fatty acids one order of magnitude higher than that of the particulate fraction. The distributional patterns of the fatty acids suggest that microbes living in the overlying soils and/or groundwater system contribute most fatty acids to the drip water. This 2-a monitoring experiment reveals that the abundance of mono-unsaturated fatty acids relative to the saturated homologues (nC16:1/nC16:0 and nC18:1/nC18:0) relate inversely to the changes of synchronous external air temperature. Higher values occur under cold conditions (winter/spring), while lower values appear in warm intervals (summer). Further studies are needed to elucidate the dynamic processes by which the external temperature affects fatty acids in drip water and to confirm the potential application of fatty acid ratios such as nC16:1/nC16:0 and nC18:1/nC18:0 in paleotemperature reconstructions. [Copyright &y& Elsevier]

Abstract: A reconstruction of Holocene rainfall is presented for southwest China — an area prone to drought and flooding due to variability in the East Asian monsoon. The reconstruction is derived by comparing a new high-resolution stalagmite δ 18O record with an existing record from the same moisture transport pathway. The new record is from Heshang Cave (30°27′N, 110°25′E; 294 m) and shows no sign of kinetic or evaporative effects so can be reliably interpreted as a record of local rainfall composition and temperature. Heshang lies 600 km downwind from Dongge Cave which has a published high-resolution δ 18O record (Wang, Y.J., Cheng, H., Edwards, R.L., He, Y.Q., Kong, X.G., An, Z.S., Wu, J.Y., Kelly, M.J., Dykoski, C.A., Li, X.D., 2005. The Holocene Asian monsoon: links to solar changes and North Atlantic climate. Science 308, 854–857). By differencing co-eval δ 18O values for the two caves, secondary controls on δ 18O (e.g. moisture source, moisture transport, non-local rainfall, temperature) are circumvented and the resulting Δδ 18O signal is controlled directly by the amount of rain falling between the two sites. This is confirmed by comparison with rainfall data from the instrumental record, which also allows a calibration of the Δδ 18O proxy. The calibrated Δδ 18O record provides a quantitative history of rainfall in southwest China which demonstrates that rainfall was 8% higher than today during the Holocene climatic optimum (≈6 ka), but only 3% higher during the early Holocene. Significant multi-centennial variability also occurred, with notable dry periods at 8.2 ka, 4.8–4.1 ka, 3.7–3.1 ka, 1.4–1.0 ka and during the Little Ice Age. This Holocene rainfall record provides a good target with which to test climate models. The approach used here, of combining stalagmite records from more than one location, will also allow quantification of rainfall patterns for past times in other regions. [Copyright &y& Elsevier]

Molecular stratigraphic analyses using gas chromatograph-mass spectrometry have been performed in the upper section (S0, L1, S1) of the Yuanbo loess–paleosol sequences in northwest China, with a record extending from the last interglaciation through the present interglaciation. The CPI (Carbon Preference Index) values of both n-alkanols and n-alkan-2-ones display variations between loess deposits and paleosols, showing a correlation with the magnetic susceptibility record, an indicator of the East Asian summer monsoon. The observed variations in the indexes in relation to changes in lithology/paleoclimate are proposed to result from microbial degradation of higher plant lipids in the paleosols. The CPI values of n-alkanes, n-alkanols, and n-alkan-2-ones are negatively correlated with δ13C of bulk organic matter. The correlations suggest that the observed glacial–interglacial variations of δ13C data in the loess stratigraphy reflect the relative importance of the contribution of paleovegetation compared with microorganisms (including both the degradation and the addition of organic matter) and allochthonous loess/soil parent materials. It is thus necessary to evaluate the contributions of the latter two before the paleovegetation can be reconstructed based on the δ13C analysis of bulk organic matter in some loess–paleosol sequences of the Chinese Loess Plateau. [Copyright &y& Elsevier]

Lipid extracts from a 61.7-cm-long subtropical stalagmite in southern China, spanning the period of ca. 10,000–21,000 yr ago as constrained by U–Th dating, were analyzed using gas chromatography–mass spectrometry. The higher plants and microorganisms in the overlying soils contribute a proportion of n-alkanes identified in the stalagmite. The occurrence of LMW (lower molecular weight) n-alkanols and n-alkan-2-ones in the stalagmite was mainly related to the soil microorganisms. We suggest that HMW (higher molecular weight) n-alkanols and n-alkan-2-ones identified in the stalagmite originate from soil organics and reflect input from contemporary vegetation. Shifts in the ratio of LMW to HMW n-alkanols or n-alkan-2-ones indicative of the variation of soil ecosystems (e.g., microbial degradation of organic matter and/or the relative abundance of soil microorganisms to higher plants) are comparable with the subtropical alkenone-SST (sea surface temperature) record of the same period. The similar trends seen in the δ13C data and the lipid parameters in this stalagmite imply that the overlying soil ecosystem response to climate might be responsible for the variation of δ13C values. [Copyright &y& Elsevier]

3-Hydroxy fatty acids (3-OH-FAs), derived from Gram-negative bacterial outer membranes, have received recent attention for their potential as new terrestrial pH and temperature proxies for palaeoclimate studies. Initial studies from altitudinal transects of contemporary soils – correlating bacterial 3-OH-FA compositions to air temperature and pH – have shown promising results. But the geographical extent of recent calibrations is limited. In this study, we analyse 3-OH-FA lipid distributions in 186 globally distributed soil samples to study the environmental factors controlling the relative distribution of the 3-OH-FA isomers. Our sample-set covers a wide range of temperatures (−0.4 to 27 °C) and pH (3.6–9.2). For the global compilation we find that the ratio of anteiso to normal 3-OH-FAs of the C 15 or C 17 homologues (RAN 15 or RAN 17) shows a strong linear relationship with mean annual air temperature (MAAT) (R2 = 0.48, p < 0.001 and R2 = 0.41, p < 0.001, respectively). Additionally, the negative logarithm of the ratio of the summed iso and anteiso to the total amount of normal 3-OH-FAs (RIAN) is also strongly anticorrelated with the soil pH (R2 = 0.66, p < 0.001). However, we find that for our 3-OH-FA based proxies there are significant differences in slope and intercept of the linear corrections at regional scales. Thus local or regional calibrations are likely preferable (at this stage of 3-OH-FA proxy development) for application to specific palaeoclimate archives. We also explore the relationship of 3-OH-FA isomer fractional abundances to environmental parameters using machine learning tool (a Gaussian Process (GP) emulator). This confirms the first order relationships to environmental parameters highlighted by the empirical equations and also derives several alternative GP emulator models for reconstructing MAAT and pH which give higher R2 values (0.66 for MAAT; 0.63 for pH) and lower RSME values (3.5 °C for MAAT; 0.76 for pH) compared to simple linear regressions at the global scale. We compare our 3-OH-FA based indices with bacterial branched glycerol dialkyl glycerol tetraethers (brGDGTs) based indices from the same soil samples. At a global scale RAN 15 and RAN 17 show negative correlations with the MBT′ 5ME -MAAT (MBT′ 5ME , methylation index of 5-methyl branched tetraethers) (r = −0.59, p < 0.001 and r = −0.42, p < 0.001, respectively), whilst RIAN shows strong linear correlations with the cyclisation ratio of branched tetraethers (CBT) (r = 0.77, p < 0.001). Similar to 3-OH-FA based temperature proxies, GDGT based temperature proxy MBT′ 5ME also showed different regional calibrations. Our new field-based correlations demonstrate the broad physiological response of Gram-negative bacterial cell membranes to external environmental changes on a global scale. We suggest that 3-OH-FA based proxies have widespread potential for palaeoenvironmental studies to estimate past MAAT and soil pH, but that regional/local and context specific calibrations may need to be applied. [ABSTRACT FROM AUTHOR]