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In order to understand the formation mechanism of CH4 during the lignin pyrolysis process, 4-(3-hydroxypropyl)-2-methoxyphenol was selected as the G-type lignin monomer model compound. Theoretical studies on its pyrolysis process were conducted by using the density functional theory (DFT) method. The results show that the key of CH4 formation in the process of lignin pyrolysis is the homolytic cleavage of the O-CH3 bond of the methoxyl functional group to generate methyl radical. Then the methyl radical will abstract H to form CH4 through the unimolecular reaction or bimolecular reaction. The former reaction is difficult to occur due to the limited number of free H radicals in the pyrolysis process of lignin. The latter reaction is more likely to take place because of the lower reaction energy barriers. Both the alkyl side chain and the characteristic functional groups of the benzene ring can undergo bimolecular reactions to donate H for methyl radicals to form CH4.

A displacement sensor based on polarization-maintaining fiber has been proposed and proved in experiment. The polarization-maintaining fiber (PMF) is sandwiched with two graded-index multimode fibers (GI MMF), which form the Mach–Zehnder interferometer (MZI) sensor. Graded-index multimode fiber serve as an optical coupler for modes conversion. The results show that with the increase of displacement, the spectrum moves to the long wavelength direction, but when temperature increases, the spectrum has a red shift, which means that the displacement and temperature can be measured separately according to the wavelength drift direction. The sensor consists of 4 mm GI MMF and 14 mm PMF, which can exhibit the displacement sensitivity of –9.275 pm/μm in the range of 0–600 μm. In addition, temperature will also affect the sensitivity of displacement measurement, so the sensitivity of the sensor to temperature is also measured. The results show that the selected monitoring dip provides a better temperature sensitivity of 33.605 pm/℃ in the range of 35–75℃. The sensor is easy to fabricate and does not has any functional coating, which make it become a good candidate in the industrial field.

Let G be a graph that admits a perfect matching M. A forcing set S for a perfect matching M is a subset of M such that it is contained in no other perfect matchings of G. The cardinality of a forcing set of M with the smallest size is called the forcing number of M, denoted by f(G, M). The forcing spectrum of G is defined as: Spec(G) = {f(G, M)∣ M is a perfect matching of G}. In this paper, by applying the Z-transformation graph (resonance graph) we show that for any polyomino with perfect matchings and any even polygonal chain, their forcing spectra are integral intervals. Further we obtain some sharp bounds on maximum and minimum forcing numbers of hexagonal chains with given number of kinks. Forcing spectra of two extremal chains are determined.

BACKGROUND China has a high prevalence of hepatitis B virus (HBV), but most chronic hepatitis B (CHB) patients do not receive standardized antiviral therapy. There are few relevant reports addressing the outcomes of the large number of CHB patients who do not receive antiviral therapy. AIM To observe the outcomes of long-term follow-up of patients with CHB without antiviral treatment. METHODS This study included 362 patients with CHB and 96 with hepatitis B cirrhosis without antiviral treatment and with only liver protection and anti-inflammatory treatment from 1993 to 1998. The median follow-up times were 10 and 7 years, respectively. A total of 203 CHB and 129 hepatitis B cirrhosis patients receiving antiviral therapy were selected as the control groups. The median follow-up times were 8 and 7 years, respectively. Kaplan-Meier curves were used to analyze the cumulative incidence of hepatocellular carcinoma (HCC), and the Cox regression model was used to analyze the risk factors for HCC. RESULTS Among the patients in the non-antiviral group, 16.9% had spontaneous decreases in HBV DNA to undetectable levels, and 32.8% showed hepatitis B e antigen (HBeAg) seroconversion. In the antiviral group, 87.2% of patients had undetectable HBV DNA, and 52% showed HBeAg seroconversion. Among CHB and hepatitis B cirrhosis patients, the cumulative incidence rates of HCC were 14.9% and 53.1%, respectively, in the non-antiviral group and were 10.7% and 31.9%, respectively, in the antiviral group. There was no difference between the two groups regarding the CHB patients (P = 0.842), but there was a difference between the groups regarding the hepatitis B cirrhosis patients (P = 0.026). The cumulative incidence rates of HCC were 1.6% and 22.3% (P = 0.022) in the groups with and without spontaneous HBeAg seroconversion, respectively. The incidence rates of HCC among patients with and without spontaneous declines in HBV DNA to undetectable levels were 1.6% and 19.1%, respectively (P = 0.051). There was no difference in the cumulative incidence of HCC between the two groups regarding the patients with drug-resistant CHB (P = 0.119), but there was a significant difference between the two groups regarding the patients with cirrhosis (P = 0.004). The Cox regression model was used for regression of the corrected REACH-B score, which showed that alanine aminotransferase > 400 U/L, history of diabetes, and family history of liver cancer were risk factors for HCC among men aged > 40 years (P < 0.05). Multifactorial analysis showed that a family history of HCC among men was a risk factor for HCC. CONCLUSION Antiviral therapy and non-antiviral therapy with liver protection and anti-inflammatory therapy can reduce the risk of HCC. Antiviral therapy may mask the spontaneous serological response of some patients during CHB. Therefore, the effect of early antiviral therapy on reducing the incidence of HCC cannot be overestimated.

Phosphatidylserine (PS) is distributed asymmetrically in the plasma membrane of eukaryotic cells. Phosphatidylserine flippase (P4-ATPase) transports PS from the outer leaflet of the lipid bilayer to the inner leaflet of the membrane to maintain PS asymmetry. The β subunit TMEM30A is indispensable for transport and proper function of P4-ATPase. Previous studies have shown that the ATP11A and TMEM30A complex is the molecular switch for myotube formation. However, the role of Tmem30a in skeletal muscle regeneration remains elusive. In the current study, Tmem30a was highly expressed in the tibialis anterior (TA) muscles of dystrophin-null (mdx) mice and BaCl2-induced muscle injury model mice. We generated a satellite cell (SC)-specific Tmem30a conditional knockout (cKO) mouse model to investigate the role of Tmem30a in skeletal muscle regeneration. The regenerative ability of cKO mice was evaluated by analyzing the number and diameter of regenerated SCs after the TA muscles were injured by BaCl2-injection. Compared to the control mice, the cKO mice showed decreased Pax7+ and MYH3+ SCs, indicating diminished SC proliferation, and decreased expression of muscular regulatory factors (MYOD and MYOG), suggesting impaired myoblast proliferation in skeletal muscle regeneration. Taken together, these results demonstrate the essential role of Tmem30a in skeletal muscle regeneration.

Phosphatidylserine (PS) is distributed asymmetrically in the plasma membrane of eukaryotic cells. Phosphatidylserine flippase (P4-ATPase) transports PS from the outer leaflet of the lipid bilayer to the inner leaflet of the membrane to maintain PS asymmetry. The β subunit TMEM30A is indispensable for transport and proper function of P4-ATPase. Previous studies have shown that the ATP11A and TMEM30A complex is the molecular switch for myotube formation. However, the role of Tmem30a in skeletal muscle regeneration remains elusive. In the current study, Tmem30a was highly expressed in the tibialis anterior (TA) muscles of dystrophin-null (mdx) mice and BaCl2-induced muscle injury model mice. We generated a satellite cell (SC)-specific Tmem30a conditional knockout (cKO) mouse model to investigate the role of Tmem30a in skeletal muscle regeneration. The regenerative ability of cKO mice was evaluated by analyzing the number and diameter of regenerated SCs after the TA muscles were injured by BaCl2-injection. Compared to the control mice, the cKO mice showed decreased Pax7+ and MYH3+ SCs, indicating diminished SC proliferation, and decreased expression of muscular regulatory factors (MYOD and MYOG), suggesting impaired myoblast proliferation in skeletal muscle regeneration. Taken together, these results demonstrate the essential role of Tmem30a in skeletal muscle regeneration.

Pyrolysis of lignocellulose biomass to produce various fuels and chemicals has gained increasing interest in recent decades. An in-depth understanding of the biomass pyrolysis reaction mechanisms i...

Bacillus thuringiensis (Bt) is efficient, strongly specific, and avirulent to humans, making it one of the most popular biopesticides in the world. Bt LLP29 is a mosquitocidal strain that was first isolated from Magnolia denudata. To understand its molecular mechanism against mosquitoes, the genome of Bt LLP29 was sequenced and annotated in this study. The LLP29 genome was found to have a total length of 5.99 Mb, with an average G + C content of 35.21%. A total of 6107 coding sequences were also detected, together with 42 rRNAs and 124 tRNAs and 135 other RNAs. With the help of annotation databases, including GO, COG, KEGG, Nr and Swiss-Prot, most unigene functions were identified. At the same time, a collinear analysis was performed on the genome of LLP29. There were also some virulence genes detected, including cry, chitinase, zwittermicin and vip.

Evapotranspiration (ET) is an important part of water cycle and energy flow in ecosystem. Accurate estimation of ET and its components is critical for understanding the impacts of ecophysiological processes on ecosystem water balance and plant water use strategy. Using the eddy-covariance technique and the micro-lysimeter, we measured ET, evaporation (蒸散发(ET)是生态系统水分循环和能量流动的重要组成部分,准确估算ET及其各组分,对认识生态生理过程对水分平衡和植物水分利用策略的影响具有重要意义。本研究于2019年5月20日至9月15日,利用涡度相关技术和微型蒸渗仪对毛乌素沙地油蒿-杨柴灌丛生态系统ET、蒸发(

Mesozoic A-type granites are widely distributed in the Lower Yangtze River Belt (LYRB) in China, but their petrogenesis and geodynamic settings are unresolved. Here, we describe geochronological an...

During fast pyrolysis of biomass, hydroxyacetone (HA, also known as 1-hydroxy-2-propanone) is a vital linear ketone product from fragmentation (ring scission) of cellulose. In this study, density functional theory (DFT) calculations are employed to reveal the HA formation mechanisms and pathways from fast pyrolysis of glucose that is the cellulose-based monosaccharide. Moreover, isotopic labeling fast pyrolysis experiments were conducted to confirm the theoretical calculation results from glucose. The results indicate that during glucose pyrolysis, HA is mainly derived from C1–C2–C3 and C4–C5–C6 segments, with C1 or C6 in the methyl group of HA. The HA from C1–C2–C3 is mainly generated via the 3-ketohexose intermediate, while the formation of the HA from C4–C5–C6 mainly involves the d -fructose intermediate. In addition, the formation of HA is parallel and competitive with the formation of levoglucosan (LG, the most important pyrolytic product of glucose), and the secondary decomposition of LG will result in trace of the HA from C4–C5–C6.

Background: To explore the associations of several genetic variants identified in the genome-wide association studies (GWAS) of European ancestry with mild renal impairment glomerular filtration rate (GFR) in Chinese Han population.Methods: Data of 1788 community-dwelling elders from the baseline survey of the ageing arm of the Rugao Longevity and Ageing Study was used. Plasma creatinine based GFR was estimated using the eGFR-EPI equations.Results: Of the 10 common polymorphisms identified in GWAS of the European ancestry, rs17319721 located in the first intron of the SHROOM3, was associated with GFR. A allele was associated with both decreased GFR level and greater odds of mild renal impairment (OR 1.12, 95% CI 1.01-1.23, p=0.029) defined by GFR2 after adjusting for multiple confounds of chronic kidney disease. In addition, compared with rs17319721-GG genotype, AA was associated with both higher depressive score and greater risk of depression prevalence, showing a pleiotropic effects of rs17319721. However, we did not found significant association of GFR levels with another 42 common polymorphisms that was previously reported to be associated with the traditional risk factors of kidney diseases.Conclusions: SHROOM3-rs17319721 is associated with GFR levels, kidney impairment, and depressive symptoms in a Chinese population.

The minimal residual disease (MRD) is the origin element that caused the relapse and drug resistance of hematological malignancies, the immune cells play a great role to clear MRD. A variety of immune cells have anti-tumor effects. However, tumor cells antagonize anti-tumor effects by reprogramming of constituents associated with tumor environment. Many different cell types, including immune cells, mesenchymal cells and tumor cells in tumor microenvironment release exosomes. The latest researches indicate that "cargo" and surface ligands carried by exosomes secreted by hematological malignant cells not only can affect the function of natural killer cell (migration, activation, proliferation, secretion and NKG2D expression), macrophage (migration and secretion) and dendritic cell (maturation and presentation), but also regulate the expression of PD-L1 and CCR2, CCL2 secretion and transformation of monocytes. The altered function of immune cells will eventually have effect on the progression of hematological malignancies.外泌体通过发挥免疫调控作用影响血液肿瘤细胞生物学特性的研究进展.微小残留病灶（minimal residual disease，MRD）是导致血液肿瘤复发及耐药的根源因素，而免疫细胞在清除微小残留病灶中发挥重要作用。多种免疫细胞具有抗肿瘤作用，但肿瘤细胞可以通过改造肿瘤微环境抑制免疫细胞的抗肿瘤作用。在肿瘤微环境中多种细胞包括免疫细胞、间充质细胞和癌细胞都可分泌外泌体（exosome）。最新研究认为，血液肿瘤细胞分泌的外泌体承载的“货物”及表面配体可调控NK细胞功能（包括迁移、活化、增殖、分泌以及NKG2D的表达）、巨噬细胞功能（迁移及分泌）及树突状细胞功能（成熟及递呈）；并且调节PD-L1、CCR2的表达、CCL2的分泌及向抑制性细胞的转化。免疫细胞功能的改变最终会影响血液肿瘤的进展.

Background To explore the associations of several genetic variants identified in the genome-wide association studies (GWAS) of European ancestry with glomerular filtration rate (GFR) in Chinese Han population. Methods Data of 1788 community-dwelling elders from the baseline survey of the ageing arm of the Rugao Longevity and Ageing Study was used. Plasma creatinine based GFR was estimated using the eGFR-EPI equations. Results Of the 10 selected polymorphisms identified in GWAS of the European ancestry, rs17319721 located in the first intron of the SHROOM3, was associated with GFR. A allele was associated with both decreased GFR level and greater odds of GFR decrease (OR 1.12, 95% CI 1.01-1.23, p=0.029) defined by GFR

In order to understand the catalytic effects of inherent inorganic elements in biomass on the pyrolysis mechanism of lignin, density functional theory with a Gaussian method of M06-2X and basic set of 6-31 + G(d,p) was employed to simulate the pyrolysis pathways of a β-O-4 type lignin dimer model compound (1-methoxy-2-(4-methoxyphenethoxy)benzene) catalyzed by NaCl and KCl which are major inorganic constituents of biomass at microscale level. The calculation results indicate that cations (Na+ and K+) in alkali metal chlorides are facile to combine with the oxygen-containing functional groups in the lignin dimer model compound. Both cations increase the Cβ−O bond length and shorten the Cα–Cβ bond length, which will further affect their bond dissociation energies. In the initial pyrolysis process of the lignin dimer model compound, NaCl and KCl can promote the Cβ–O homolytic reaction and concerted decomposition reaction, while restrain the Cα–Cβ homolytic reaction. Therefore, the lignin dimer model compound decomposes mainly through the concerted decomposition and Cβ–O homolytic mechanisms under NaCl and KCl catalytic pyrolysis conditions, producing 1-methoxy-4-vinylbenzene, 1-ethyl-4-methoxybenzene, 2-methoxyphenol, catechol and 2-hydroxybenzaldehyde, among which NaCl and KCl have inhibitory effect on 2-hydroxybenzaldehyde, but have promoting effect on the other pyrolytic products.

The origin of A-type granites has been the subject of great debate, especially the enigmatic synchronous A1- and A2-type granites. Cretaceous (~125 Ma) A1- and A2-type granites are common throughout the Lower Yangtze River Belt (LYRB), eastern China. However, their genesis still remains unclear. In this study, in-situ zircon Oisotopic data and chemical compositions of the Huayuangong (HYG) A-type granites in Anhui province, provide new insights into the origin and evolution of A-type granites in the LYRB, as well as the genetic link for synchronous A1- and A2-type granites. The HYG granites include syenogranite (75.9 wt%–76.6 wt% SiO2) and quartz syenite (66.1 wt%–66.9 wt% SiO2). Both are metaluminous and belong to ferroan series. They are characterized by high alkalis (K2O + Na2O = 8.36 wt%–8.55 wt% and 11.7 wt%–11.9 wt%), high field strength elements (Zr + Nb + Ce + Y = 909 ppm–1269 ppm and 1092 ppm–1329 ppm) and high Ga/Al ratios (10,000 ∗ Ga/Al = 4.91–4.96 and 2.64–2.68). The zircon saturation thermometer results indicate high magmatic temperatures (896–964 °C and 860–882 °C). All those geochemical features show an A-type granite affinity. They can be further classified into A1-and A2-type granites, corresponding to reduced and oxidized A-type granites, respectively. Additionally, the in-situ zircon O-Hf isotope compositions are also distinctly different, with δ18O = 4.7‰–6.0‰ and eHf(t) = −1.5 to −3.6 for A1-type granites, and δ18O = 7.0‰–7.8‰ and eHf(t) = −3.3 to −6.9 for A2-type granites. The geochemical signatures and newly discovered δ18O and eHf(t)values of the two A-type granite subgroups, indicate that they were derived from different source components and under disparate physicochemical conditions (e.g.,temperature, redox state and water contents). Lithospheric mantle-like isotopic data from zircons of A1-type granites suggest fractional crystallization of reduced, anhydrous basaltic magmas resulting in the formation of A1-type granites. In contrast, A2-type granites with relatively high δ18O and negative eHf values were generated from partial melting of the lithospheric mantle which was metasomatized by slab-derived melts/fluids. The coexisting A1- and A2-type granites were formed under the extensional setting where lithospheric thinning and asthenosphere upwelling occurred.

The Lower Yangtze River Belt in eastern China preserves evidence for widespread Mesozoic magmatism. Geochronological and geochemical studies have been conducted on the magmatic rocks and their associated mineral deposits; however, the relationships and melting conditions of spatially associated I- and A-type granites remain poorly constrained. The Qingyang–Jiuhuashan granitic complex in southern Anhui Province, eastern China, comprises primarily hornblende-bearing granodiorite, monzogranite, alkali-feldspar granite, and granitic porphyry, which yield zircon U Pb ages of 142.2 ± 1.3, 134.6 ± 1.2, 126.4 ± 1.9, and 125.9 ± 1.2 Ma, respectively. Zircon grains from an enclave in the monzogranite yield an age of 134.5 ± 1.1 Ma, similar to that of the host rock. The ages are consistent with the timing of regional magmatic events in southern Anhui Province. Whole-rock geochemical compositions indicate that the granodiorite and monzogranite represent I-type granites, whereas the alkali-feldspar granite and granitic porphyry display A-type signatures. The I- and A-type granites yield similar whole-rock Sr Nd isotopic compositions, but distinct zircon δ18O values. We infer that the I-type granites were produced through water-fluxed melting of Mesoproterozoic basement during subduction of the paleo-Pacific plate. The A-type granites were generated through partial melting of the lower crust, triggered by extensional upwelling of mantle-derived magmas that provided heat and alkali-rich fluids. We identify three stages of Cretaceous tectono-magmatic activity that occurred in response to ridge subduction and subsequent slab rollback beneath eastern China.

Hepatocellular carcinoma (HCC), a common malignant tumor, has been regarded as a leading cause of cancer-related deaths globally. Astragaloside IV (AS-IV) was reported to participate in the regulation of multiple tumors. However, the role of AS-IV in HCC was still unclear in HCC. Bioinformatics analysis and function or mechanism experiments including RT-qPCR, MTT assay, flow cytometry, Western blot, luciferase reporter assay and xenografts assays were applied to investigate the function of AS-IV, miR-150-5p and CTNNB1. We discovered that AS-IV treatment was supposed to significantly increase miR-150-5p level. In addition, AS-IV accelerated cell apoptosis by inducing miR-150-5p in vitro and in vivo. Furthermore, AS-IV increased cell apoptosis rate through reducing β-catenin level in vitro and in vivo. In detail, AS-IV triggered a decline of Bax and a rise of Bcl-2 in HCC cells and xenograft tissues. In mechanism, we validated the combination between miR-150-5p and CTNNB1. Moreover, miR-150-5p could negatively regulate CTNNB1 level by binding to its3'UTR. Finally, rescue assay demonstrated that CTNNB1 overexpression partially rescued the inhibitive effect on tumor growth and promotive influence on cell apoptosis caused by miR-150-5p amplification. The up-regulation of miR-150-5p induced by AS-IV suppressed the progression of HCC by repressing β-catenin, providing a new molecular target for the utilization of AS-IV In the treatment of HCC.

Adakitic rocks with high MgO content and lower crust affinity at convergent margins provide important constraints on arc crust evolution and regional tectonics. An integrated study on the only adakitic pluton with high MgO content and its mafic microgranular enclaves (MMEs) in the Early Paleozoic North Qinling arc terrane was conducted in this paper. Zircons from 2 host rock samples yielded identical weighted mean ages of 428 Ma. The MMEs contain two types of zircons: type 1 zircons share similar morphology, chemical composition, and indistinguishable age with those from the host rock; type 2 zircons yielded an older age of 450 Ma. The similarity in zircon Hf isotopic composition for these zircons indicates a cognate origin of the MMEs. However, the lower Ce4+/Ce3+, higher crystallization temperature and the LREE overabundance of type 2 zircons indicate that mafic intrusions in the lower arc crust were subjected to a post-magmatic event at similar to 450 Ma. Samples from the Tangzang pluton are characterized by typical adakitic geochemical features, and high MgO (Mg#: 50-52), Cr, Ni, and Ba contents. Considering their similar isotopic compositions with the Neoproterozoic metabasites in the North Qinling terrane, we argue that the Tangzang pluton was generated by crustal anatexis of two sources with contributions from the metasomatized mantle wedge. The mantle connection was achieved by aqueous melt-fluxed melting of a "hot zone'' in the lower arc crust. This implies that andesitic continental crust with Mg# of similar to 0.5 may also be associated with fluxed-melting of the lower arc crust.

Apatite is ubiquitous in A-type granites, and can be used to elucidate the volatile contents of the silicate melt, which reflect its source characteristics. A-type granites have been recognized as a distinct group of granites. A1- and A2-type subgroups are produced under different extensional settings. However, the details of the mechanisms behind the distinctive geochemical characteristics of A1- and A2-type granites remain obscure. Belts of Cretaceous A1- and A2-type granites occur along the Lower Yangtze River Belt in eastern China. Here we investigated the major and trace element compositions of apatites from contemporary A1- and A2-type granites at different localities along the Lower Yangtze River Belt, in order to decipher their discrepant source processes. Apatites from A1- and A2-type granites show similar major and trace elements, but differ in their F and Cl concentrations. Apatites from A1-type granites in the eastern part of the Lower Yangtze River Belt have much lower F and higher Cl concentrations compared to A2-type granites in the western part. Moreover, from the east to the west, the F concentrations of apatites from A1-type granites increase, while the Cl concentrations decline. In a subducted plate, F is retained by amphibole, chlorite, serpentine and mica minerals through the amphibolite stage, and finally by phengite and lawsonite during the eclogite stage, whereas, Cl is controlled by amphibole, chlorite and serpentine. The high and varied Cl concentrations in A1 subgroup apatites, therefore, may be attributed to the breakdown of amphibole, chlorite and/or serpentine decomposition during partial melting of subducted oceanic crust releasing a large amount of Cl at shallower depth. In contrast, F is transported to deeper depths in the subducted oceanic crust, and released through breakdown of phengite and lawsonite, making an important contribution to the formation of A2-type granites. Apatites from A1- and A2-type granite samples show regular changes in LREE/HREE, LREE/MREE and MREE/HREE ratios with increasing distance from the location of the subduction zone, probably as the result of nonsynchronous dehydration of the serpentine and phengite at different stages during subduction. We propose that A1- and A2-type granites on the Lower Yangtze River Belt were derived from sources metasomatised by fluids originating from the breakdown of amphibole, chlorite and/or serpentine with higher Cl, lower F, and from phengite and/or lawsonite with relatively higher F but lower Cl, respectively.

Paleoproterozoic A-type granites are widely outcropped in the North China Craton (NCC), particularly in the Trans-North China Orogen. However, their genesis and tectonic significance remain obscure. Here we report systematic studies on geochronology and geochemical characteristics of A-type granite in Huayangchuan, south margin of the NCC. The samples are enriched in total alkali (K2O + Na2O > 8.97 wt%), and depleted in MgO (0.84–0.93 wt%), CaO (1.28–1.90 wt%) and P2O5 (0.18–0.20 wt%), with high FeOT/MgO (5.69–6.67). They are characterized by high Zr + Y + Nb + Ce values (1293–1392 ppm) and 10,000 × Ga/Al ratios (3.14–3.35), which are typical characteristics of A-type granite. The Huayangchuan A-type granite can be further classified as A1-type subgroup based on particular geochemical features, e.g., low Y/Nb (0.87–1.00) and Yb/Ta (0.88–1.10). High precision zircon U–Pb dating of the A-type granite by secondary ion mass spectrometry (SIMS) yields Paleoproterozoic 207Pb/206Pb ages of 1829.5 ± 2.5 Ma. The low zircon ɛHf(t) values (−6.97 to −10.45), along with zircon Hf model age of 2.7–2.9 Ga, indicate that the Huayangchuan A-type granite was derived from partial melting of the ancient continental crust with contribution of enriched mantle components. The low zircon δ18O composition (4.00 to 6.78‰) indicates that the zircons were crystallized from low δ18O magmas, which derived from the crust metasomatized by low δ18O mantle fluids or melts. The E-W trend A1-type granitic plutons in the NCC are generally outcropped in a rift tectonic regime, which is consistent with the development of the mantle plume in the Xiong'er district. The large volume of basaltic magmas, generated by mantle plume head, underplated the lower continental crust and formed the Huayangchuan A-type granite.

Unimolecular decomposition mechanism is widely recognized as the major mechanism in lignin pyrolysis studies. In fact, during the real pyrolysis process, lignin and its derived intermediates, radicals and primary products are coexisting in the complex pyrolysis system. They may interact with each other, which will ultimately affect the whole pyrolysis process. However, current unimolecular decomposition mechanism does not take these interactions into consideration. In this study, density functional theory (DFT) methods and analytical pyrolysis-gas chromatography/mass spectrometry (Py-GC/MS) experiments are employed to explore the intermolecular interaction mechanism of lignin pyrolysis. The results indicate that strong interactions between radicals and lignin or its derived pyrolytic products will take place during the pyrolysis process through H-abstraction reactions. Therefore, intermolecular interaction mechanism, rather than unimolecular decomposition mechanism, should dominate the lignin pyrolysis process. These interactions can promote the primary and secondary decomposition reactions of lignin and its derived pyrolytic products, and simultaneously stabilize the radicals.

Fast pyrolysis of biomass will produce various furan derivatives, among which 5-hydroxymethyl furfural (5-HMF) and furfural (FF) are usually the two most important compounds derived from holocellulose. In this study, density functional theory (DFT) calculations are utilized to reveal the formation mechanisms and pathways of 5-HMF and FF from two hexose units of holocellulose, i.e., glucose and mannose. In addition, fast pyrolysis experiments of glucose and mannose are conducted to substantiate the computational results, and the orientation of 5-HMF and FF is determined by 13C-labeled glucoses. Experimental results indicate that C1 provides the aldehyde group in both 5-HMF and FF, and FF is mainly derived from C1 to C5 segment. According to the computational results, glucose and mannose have similar reaction pathways to form 5-HMF and FF with d -fructose (DF) and 3-deoxy-glucosone (3-DG) as the key intermediates. 5-HMF and FF are formed via competing pathways. The formation of 5-HMF is more competitive than that of FF, leading to higher yield of 5-HMF than FF from both hexoses. In addition, compared with glucose, mannose can form 5-HMF and FF via extra pathways because of the epimerization at C2 position. Therefore, mannose pyrolysis results in higher yields of 5-HMF and FF than glucose pyrolysis.

Accretionary orogens are the primary sites for continental growth, but the rate and amount of crust generation throughout its evolution are poorly constrained. In this contribution, our new results about the genesis of two intermediate-felsic plutons are combined with a compiled granitoid dataset to evaluate the amount and rate of crustal growth throughout the evolution of the Western Kunlun orogen, which is a typical accretionary orogen associated with the consumption of the Proto-Tethys during the early Paleozoic. The ca.446 Ma Sanshili pluton was formed through interactions between metasomatized mantle wedge-derived oxidized magmas and the lower arc crust, as indicated by high whole-rock Mg#, high Ce4+/Ce3+ ratios (308–861) of ca.446 Ma zircons, and the existence of inherited zircons with ages of 546–472 Ma. The Yirba dioritic to granodioritic pluton was emplaced at 474 ± 3 Ma. Samples from the Yirba pluton are characterized by high K2O content, higher Mg# (40–49) than pure crustal melts, slightly higher Y + Nb concentrations, and high Th/Nb ratios, and slightly enriched to depleted Hf–Nd isotopes. Combined with the presence of the 502–531 Ma inherited zircons, the Yirba pluton is suggested to from through differentiation of the metasomatized lithospheric mantle derived-magmas beneath the juvenile intra-oceanic arc in combination with crustal reworking during regional extensions. The Yirba pluton, together with contemporary A1-type granites, thus marks an extension event at ca. 475 Ma in the Western Kunlun orogen. The compiled dataset reveals three magmatic flare-ups at 530–500 Ma, 480–470 Ma, and 445–430 Ma, corresponding to two slab rollback events and the slab break-off after the final closure of the Proto-Tethys. The three episodes of more intensive magmatism are associated with more radiogenic Hf–Nd isotopes and increased Nb/La and Nb/Y ratios, indicating more contributions from intraplate-like sources during lithospheric extensions. Meanwhile, element ratios (La/Yb, Sm/Yb, and Sr/Y) that are sensitive to crustal thickness are also elevated. These phenomena are consistent with rapid juvenile crust generation during extensional stages of accretionary orogens. Our study has also shown that the rate of new crust production is quite uniform for different extensional events. The crustal generation rate during slab break-off is much higher than that during slab rollback, although the proportions of juvenile inputs in granitoids formed during slab rollback are relatively higher. This may reflect extra inputs from partial melting of oceanic slabs and subducting sediments like those in continental collision zones and/or rapid asthenospheric upwelling coupled with enhanced crust reworking during slab break-off.

During biomass fast pyrolysis process, the interactions among biomass components will affect the pyrolytic products distribution. In this study, d-glucose and a β-O-4 type lignin model dimer (LMD, 1-(4-hydroxy-3-methoxyphenyl)-2-(2-methoxyphenoxy)propane-1,3-diol) were selected as the model compounds of cellulose and lignin. The interaction characteristics and mechanism during their fast co-pyrolysis process were investigated by combined pyrolysis–gas chromatography/mass spectrometry (Py–GC/MS) experiments and density functional theory (DFT) calculations. The Py–GC/MS results indicated that during fast co-pyrolysis process, the presence of LMD significantly decreased the formation of levoglucosan (LG) from d-glucose, while promoted the formation of linear carbonyls and furans. Meanwhile, the presence of d-glucose enhanced the decomposition of LMD to generate phenolic compounds. The DFT calculations revealed that d-glucose would interact with a homolysis radical of LMD to form a ten-membered ring transition state. The formed complex transition state changed the energy barriers of certain pyrolytic reactions of d-glucose and LMD, thus affecting the pyrolytic products distribution.

Background Bacillus thuringiensis israelensis (Bti) is a widely used mosquitocidal microbial pesticide due to its high toxicity. ATP-binding proteins (ABP) are prevalently detected in insects and are related to reaction against Bti toxins. However, the function of ABP in mosquito biocontrol is little known, especially in Aedes aegypti. Therefore, this study aimed to clarify the function of ABP in Ae. aegypti against Bti toxin. Results Aedes aegypti ABP (GenBank: XM_001661856.2) was cloned, expressed and purified in this study. Far-western blotting and ELISA were also carried out to confirm the interaction between ABP and Cry11Aa. A bioassay of Cry11Aa was performed both in the presence and absence of ABP, which showed that the mortality of Ae. aegypti is increased with an increase in ABP. Conclusions Our results suggest that ABP in Ae. aegypti can modulate the toxicity of Cry11Aa toxin to mosquitoes by binding to Bti toxin. This could not only enrich the mechanism of Bt toxin, but also provide more data for the biocontrol of this transmission vector.

Fast pyrolysis of biomass will produce complex pyrolytic products. Hydroxyacetaldehyde (HAA) is one of the most important pyrolytic products, derived from fragmentation (ring scission) of holocellulose. In this study, density functional theory (DFT) calculations are employed to reveal the HAA formation mechanisms from fast pyrolysis of four holocellulose-based monosaccharides, i.e., β- d -glucopyranose, β- d -mannopyranose, β- d -xylopyranose and O -acetyl-β- d -xylopyranose. Moreover, the theoretical calculation results of the β- d -glucopyranose are confirmed by isotopic labeling fast pyrolysis experiments. The results indicate that during β- d -glucopyranose pyrolysis, the HAA is mainly derived from C1 C2, C5 C6 and C3 C4. The C2 C3 bond is easy to break via retro-aldol reaction to form 1,2-ethenediol (ED) which will tautomerize into the HAA from C1 C2 with high selectivity, accounting for the largest proportion of total HAA. The second largest origin of the HAA is the C5 C6 segment in multiple pathways with low energy barriers. However, these reactions to form the HAA from C5 C6 are thermodynamically unfavorable, and moreover, there are facile competing reactions to produce other products. Importantly, the HAA and levoglucosan (LG) are mainly formed via competing parallel pyrolytic pathways. Only a little HAA will be derived from the secondary cracking of LG. In addition, the HAA formation mechanisms from β- d -mannopyranose and β- d -xylopyranose are similar as those from β- d -glucopyranose. However, O -acetyl-β- d -xylopyranose behaves differently from the other three monosaccharides due to the acetyl group at C2 position. The HAA will be mainly derived from C4 C5, accompanied with the formation of acetic acid (AA) from scission of the acetyl branch.

The homolytic bond dissociation energies (BDEs) of Cα−O and Cβ−O bonds in 27 lignin trimer model compounds were calculated by employing density functional theory methods at M062X level with 6−31++G(d,p) basis set; the effects of various substituent groups (CH3, CH2OH and OCH3) at different positions on the BDEs of Cα−O and Cβ−O bonds were investigated. The results indicated that a single methoxyl group at R2 or R3 has a minor influence on the BDE of Cβ−O bond, whereas two methoxyl groups at R2 and R3 lead to an obvious decrease in the BDE of Cβ−O bond. The decrement in the BDE of Cβ−O bond from the methoxyl groups at R2 and R3 can be enhanced by the methoxyl groups at R4 and R5, but is hardly influenced by the substituent groups at R1. Meanwhile, the BDE of Cα−O bond is gradually reduced when the H atoms at R4 and R5 are successively substituted with methoxyl groups; the decrement in the BDE of Cα−O bond from the methoxyl groups at R4 and R5 can be strengthened by the methoxyl groups at R2 and R3. Furthermore, the methyl and hydroxymethyl groups at R1 can gradually increase the BDE of Cα−O bond and this effect is weakened when the H atoms at R2 and R3 are successively substituted with methoxyl groups. The methyl group at R1 has little influence on the BDE of Cβ−O bond, which is however dramatically increased by the hydroxymethyl group at R1.

Most granites and related calc-alkaline silicic volcanic rocks from the United States and New Zealand Cordillera are saturated with zircon between 65 and 70 wt% SiO2. For this silica interval, zircon saturation temperatures ( T zr) are universally lower ( 900 °C). The values contrast with T zr from alkaline rocks from the Cenozoic U.S. Cordillera, which are typically >800 °C for 65–70 wt% SiO2. Case studies of titanium-in-zircon thermometry from the U.S. Cordillera also suggest that alkaline magma injections into granitic magma chambers are hot, but calc-alkaline magma injections are usually cooler. A model is presented suggesting that silicic Cordilleran magmas form in magmatic arcs where hydrous basaltic magmas solidify in the arc root, producing mafic underplates that exsolve aqueous fluids, which transfer to the crust and promote water-fluxed partial melting at ambient pressure-temperature (∼750–800 °C at 8 kbar) conditions. Subsequent rock-buffered melting reactions modulate the water content of arc magmas. The granitic partial melts are water undersaturated, rise adiabatically as increments, but stall in the middle to upper crust, building cool and hydrous, crystal-rich magma chambers (batholiths). However, injections of hotter magmas are required to drive volcanic eruption. In the backarc, granitic magma chambers are intermittently recharged with hotter, drier alkaline magmas, which are produced mostly by decompression melting during lithospheric extension, not hydrous fluxing. This highlights the control of subduction dynamics on water content and consequently magmatic temperatures in silicic magma systems.