Search

The identification of cross-sectional loss in cables due to corrosion is crucial for evaluating the remaining strength of bridge cables. To accurately determine the cross-sectional loss rate, this paper derived a three-dimensional magnetic dipole model for spatial cable damage. The study employed an independently designed self-magnetic flux leakage (SMFL) sensor array to detect corrosion on a bundle of 37 parallel steel wires. The analysis investigated the correlation between corrosion degrees and SMFL signal features. The results show that the spatial magnetic field inversion collected by the sensor array device is more accurate. The cable damage location can be pinpointed by observing abrupt changes in the Bx and Bz curves. Additionally, this paper introduces five corrosion characterization features, all correlated with the cable cross-sectional loss rate. However, recognition stability using a single characteristic value is insufficient. The cable cross-sectional loss rate identification method, utilizing a back propagation neural network in conjunction with multiple characteristic indicators, demonstrates robust quantitative and adaptive capabilities. The maximum relative error of this method is 7.6%, offering a new perspective for future cable damage detection. [ABSTRACT FROM AUTHOR]

A fundamental goal in cancer-associated genome sequencing is to identify the key genes. Protein–protein interactions (PPIs) play a crucially important role in this goal. Here, human reference interactome (HuRI) map was generated and 64,006 PPIs involving 9094 proteins were identified. Here, we developed a physical link and co-expression combinatory network construction (PLACE) method for genes of interest, which provides a rapid way to analyze genome sequencing datasets. Next, Kaplan‒Meier survival analysis, CCK8 assays, scratch wound assays and Transwell assays were applied to confirm the results. In this study, we selected single-cell sequencing data from patients with hepatocellular carcinoma (HCC) in GSE149614. The PLACE method constructs a protein connection network for genes of interest, and a large fraction (80%) of the genes (screened by the PLACE method) were associated with survival. Then, PLACE discovered that transmembrane protein 14B (TMEM14B) was the most significant prognostic key gene, and target genes of TMEM14B were predicted. The TMEM14B-target gene regulatory network was constructed by PLACE. We also detected that TMEM14B-knockdown inhibited proliferation and migration. The results demonstrate that we proposed a new effective method for identifying key genes. The PLACE method can be used widely and make outstanding contributions to the tumor research field. [ABSTRACT FROM AUTHOR]

The global regulator LaeA and its orthologs govern the morphogenetic development and secondary metabolism of several filamentous ascomycetes. In Aspergillus niger, it has been shown that an LaeA ortholog (AnLaeA) regulates the production of citric acid and secondary metabolites. In this work, we constructed AnlaeA disruption and overexpression strains to investigate the roles of AnLaeA in morphological development and ochratoxin A (OTA) biosynthesis in A. niger. Phenotypic observation, chemical analysis, and gene expression analysis indicated that AnLaeA acts as a negative regulator of conidial morphogenesis and positively regulates gene expression of the OTA cluster in A. niger grown in CYA medium. However, it was observed that the upregulation of gene expression of the OTA cluster does not necessarily increase OTA production. Our results contribute to a better understanding of the AnlaeA regulatory mechanism and suggest the AnlaeA gene as a potential target for developing control strategies for A. niger infection and OTA biosynthesis. [ABSTRACT FROM AUTHOR]

In this era characterized by fast development of urbanization, public transportation problem is one of the main obstacles for people to promote their life satisfaction in China. This paper aims at discussing problems on mass customization public transportation, providing suggestions and consults for its sustainable development and improvement. A mass customization model for public transportation is constructed based on client requirement and cost analysis, and case studies are made to validate route planning results. Results show that mass customization public transportation can make high profit for bus companies and relieve traffic congestion and air contamination. [ABSTRACT FROM AUTHOR]

The redox evolution of Archean upper mantle impacted mantle melting and the nature of chemical equilibrium between mantle, ocean and atmosphere of the early Earth. Yet, the origin of these variations in redox remain controversial. Here we show that a global compilation of ∼3.8-2.5 Ga basalts can be subdivided into group B-1, showing modern mid-ocean ridge basalt-like features ((Nb/La)PM ≥ 0.75), and B-2, which are similar to contemporary island arc-related basalts ((Nb/La)PM < 0.75). Our V-Ti redox proxy indicates a more reducing upper mantle, and the results of both ambient and modified mantle obtained from B-1 and B-2 samples, respectively, exhibit a ∼1.0 log unit increase in their temporal evolution for most cratons. Increases in mantle oxygen fugacity are coincident with the changes in basalt Th/Nb ratios and Nd isotope ratios, indicating that crustal recycling played a crucial role, and this likely occurred either via plate subduction or lithospheric drips. The basalt V-Ti redox proxy indicates that both of the Archean ambient and modified mantle exhibit a ~1.0 log unit increase in their evolution for most cratons, possibly derived by widespread crustal recycling. [ABSTRACT FROM AUTHOR]

As an emerging class of the two-dimensional (2D) materials, MXenes exhibit excellent antifriction and wear resistance potential in lubrication systems. However, as a lubricant additive, their stable dispersion in base oils remains a great challenge. Optimizing the microstructure has previously been demonstrated to be an effective strategy to improve the dispersibility of inorganic materials in oil-based lubricants. In this work, the structural modulation of MXene through in-situ growth of hydroxysalts (HS) to form a heterostructure was achieved. Compared with pristine MXene and HS, the dispersion stability of MXene/HS composite in poly-α-olefin-10 (PAO-10) base oil was significantly improved due to the self-dispersion and restacking-resistant properties of the heterostructure. Additionally, the lubrication performance of the obtained composite as an additive in PAO-10 was investigated. The results showed that the coefficient of friction of the oil sample containing the MXene/HS composite was steadily maintained at approximately 0.12 under four different loads of 200, 250, 300, and 350 N (corresponding to maximum Hertz contact pressures of 2.72, 2.9, 3.12, and 3.28 GPa, respectively). Moreover, the wear track width, wear scar diameter, and wear volume were reduced by 49.1%, 49.4%, and 82.0%, respectively. This study introduces a viable pathway to transform non-lipophilic Ti3C2Tx MXene into an attractive lubricant additive with excellent self-dispersing ability through structural regulation. [ABSTRACT FROM AUTHOR]

Micro- and small businesses are more vulnerable to natural hazards than the larger ones. However, there are few attempts to systematically assess their vulnerabilities. Existing business vulnerability assessments use aggregate-level data, which poorly account for the prevalence of micro- and informal businesses in some areas. Also, they focus on business sensitivity and have not incorporated key elements of adaptive capacity into analysis. This study explores a firm-level assessment approach that would work better under resource and data constraints, which are common challenges to developing-country researchers. Surveys were conducted in four jurisdictions of China: Sanya, Zhuhai, Macao and Hong Kong. A total of 596 urban and rural businesses were involved. Indicators of business sensitivity, exposure and adaptive capacity were built into a structured questionnaire. The results were turned into a set of metrics for cross-location comparison. Aggregated scores suggest that business vulnerabilities increase from Sanya, Zhuhai, Hong Kong to Macao. Additional tests show that the integrated vulnerability scores are geographically differentiated and demonstrate compatibility with theoretical expectations. The value of this approach lies in its appropriate and realistic requirements for conducting business vulnerability assessments in small, isolated or less developed communities. Future applications need to overcome some uncertainties in the assessment. [ABSTRACT FROM AUTHOR]

Constraining thickness and geothermal gradient of Archean continental crust are crucial to understanding geodynamic regimes of the early Earth. Archean crust-sourced tonalitic–trondhjemitic–granodioritic gneisses are ideal lithologies for reconstructing the thermal state of early continental crust. Integrating experimental results with petrochemical data from the Eastern Block of the North China Craton allows us to establish temporal–spatial variations in thickness, geothermal gradient and basal heat flow across the block, which we relate to cooling mantle potential temperature and resultant changing geodynamic regimes from vertical tectonics in the late Mesoarchean (~2.9 Ga) to plate tectonics with hot subduction in the early to late Neoarchean (~2.7–2.5 Ga). Here, we show the transition to a plate tectonic regime plays an important role in the rapid cooling of the mantle, and thickening and strengthening of the lithosphere, which in turn prompted stabilization of the cratonic lithosphere at the end of the Archean. Constraining the thermal state of the lithosphere is crucial to understanding geodynamic regime in early Earth. Here the authors reconstruct ~2.9–2.5 Ga thermal structure of continental lithosphere of the North China Craton using TTG and propose a systematic Archean geodynamic evolution process. [ABSTRACT FROM AUTHOR]

Apoferritin (APO) with a diameter of ~12 nm is a naturally occurring protein assembly in living organisms. APO is made of 24 protein subunits that form a nanocage with an inner diameter of ~8 nm. Thus far, the loading of only a few nanoparticles inside the nanocage of APO has been reported. In this study, the mass loading of D-glucuronic acid (GA)-coated ultrasmall gadolinium oxide (Gd2O3) nanoparticles (UGNPs) (GA-UGNPs) (davg = 1.9 nm) inside and outside the nanocage of APO was investigated. The in vitro cytotoxicity and relaxometric properties were investigated. This study indicates that APO is an extremely useful bio-material, which can be used for mass loading of various nanoparticles for biomedical applications. [ABSTRACT FROM AUTHOR]

Mitochondrial abnormalities accelerate the progression of ischemic brain damage. Sirtuin 3 (SIRT3) is mainly found in mitochondria and affects almost all major aspects of mitochondrial function. Luteolin, a flavonoid with diverse biological properties, including antioxidant activity, inhibition of cell apoptosis and regulation of autophagy. It also modulates the activity of AMP activated kinase and/or sirtuin 1 (SIRT 1) by regulating the expression of sirtuins. We investigated the protective effects of luteolin on cerebral ischemia-reperfusion. It was found through experiments that luteolin reduced the infarcted area of MCAO rat model, and based on the experimental results, it was inferred that luteolin affected the AMPK, mTOR and SIRT3 pathways, thereby protecting brain cells. As expected, we found that luteolin can reduce the neurological function score, the degree of cerebral edema, the cerebral infarction volume, alleviate morphological changes in the cortex and hippocampus, increase neuron survival and decrease the number of apoptotic neurons. At the same time, luteolin significantly reduced the number of GFAP and Iba-1 positive glial cells in the hippocampus while enhanced the scavenging of oxygen free radicals and the activity of SOD in mitochondria. Addtionally, it can also enhance antioxidant capacity via the reversal of mitochondrial swelling and the mitochondrial transmembrane potential. Moreover, luteolin can increase SIRT3-targeted expression in mitochondria, decrease the phosphorylation of AMPK, and increase phosphor-mTOR (p-mTOR) levels, which may have occurred specifically through activation of the SIRT3/AMPK/mTOR pathway. We speculate that luteolin reduces the pathological progression of CIRI by increasing SIRT3 expression and enhancing mitochondrial function. Therefore, the results indicate that luteolin can increase the transduction of SIRT3, providing a potential mechanism for neuroprotective effects in patients with cerebral ischemia. [ABSTRACT FROM AUTHOR]

Small community businesses bear the brunt of climate change impacts. Studies of the vulnerability and resilience of such businesses predominantly focus on firm-level characteristics and organizational issues. This paper addresses the lack of individual-level considerations. It explores an analytical approach that draws upon the concepts of social capital and sense of place for understanding community businesses' resilience to extreme weather. An empirical study was conducted to investigate whether and how the attributes of these concepts are related to adaptation practice. This study is based on a structured questionnaire survey of community businesses at various locations around the Pearl River Estuary that are exposed to storm surges. The findings partially support the hypothesis that action is more likely to be taken when social capital is strong. Community businesses are more likely to adopt adaptation strategies when their owners or operators perceive a higher level of social expectation, but are less likely to do so when they have better relationships with the people around them. This study indicated the potential for moral hazard driven by good social relationships and supported the understanding of small community businesses as firms and social agents in responding to climate change impacts. There is a need for recognizing the social dimensions of small businesses' rationality in their adaptation and hazard adjustment, and strengthening their engagement with community-based adaptation through social institutions. [ABSTRACT FROM AUTHOR]

Studies of the genetic diversity and population structure of Oenococcus oeni (O. oeni) strains from China are lacking compared to other countries and regions. In this study, amplified fragment length polymorphism (AFLP) and multilocus sequence typing (MLST) methods were used to investigate the genetic diversity and regional evolutionary patterns of 38 O. oeni strains isolated from different wine-making regions in China. The results indicated that AFLP was markedly more efficient than MLST for typing O. oeni strains. AFLP distinguished 37 DNA patterns compared to 7 sequence types identified using MLST, corresponding to discriminatory indices of 0.999 and 0.602, respectively. The AFLP results revealed a high level of genetic diversity among the O. oeni strains from different regions of China, since two subpopulations and an intraspecific homology higher than 60% were observed. Phylogenetic analysis of the O. oeni strains using the MLST method also identified two major phylogroups, which were differentiated into two distinct clonal complexes by minimum spanning tree analysis. Neither intragenic nor intergenic recombination verified the existence of the clonal population structure of the O. oeni strains. [ABSTRACT FROM AUTHOR]

Objective: To identify useful native promoters of Corynebacterium glutamicum for fine-tuning of gene expression in metabolic engineering.Results: Sixteen native promoters of C. glutamicum were characterized. These promoters covered a strength range of 31-fold with small increments and exhibited relatively stable activity during the whole growth phase using β-galactosidase as the reporter. The mRNA level and enzymatic activity of the lacZ reporter gene exhibited high correlation (R2 = 0.96) under the control of these promoters. Sequence analysis found that strong promoters had high similarity of the -10 hexamer to the consensus sequence and preference of the AT-rich UP element upstream the -35 region. To test the utility of the promoter library, the characterized native promoters were applied to modulate the sucCD-encoded succinyl-CoA synthetase expression for l-lysine overproduction.Conclusions: The native promoters with various strengths realize the efficient and precise regulation of gene expression in metabolic engineering of C. glutamicum. [ABSTRACT FROM AUTHOR]

Cytochrome P450 (CYPs) and UDP-glucuronosyltransferases (UGTs) play important roles in the metabolism of exogenous and endogenous compounds. The gene transcription of CYPs and UGTs can be enhanced or reduced by transcription factors (TFs). This study aims to explore novel TFs involved in the regulatory network of human hepatic UGTs/CYPs. Correlations between the transcription levels of 683 key TFs and CYPs/UGTs in three different human liver expression profiles ( n = 640) were calculated first. Supervised weighted correlation network analysis (sWGCNA) was employed to define hub genes among the selected TFs. The relationship among 17 defined TFs, CYPs/UGTs expression, and activity were evaluated in 30 liver samples from Chinese patients. The positive controls (e.g., PPARA, NR1I2, NR1I3) and hub TFs (NFIA, NR3C2, and AR) in the Grey Module were significantly and positively associated with CYPs/UGTs expression. And the cancer- or inflammation-related TFs (TEAD4, NFKB2, and NFKB1) were negatively associated with mRNA expression of CYP2C9/CYP2E1/UGT1A9. Furthermore, the effect of NR1I2, NR1I3, AR, TEAD4, and NFKB2 on CYP450/UGT1A gene transcription translated into moderate influences on enzyme activities. To our knowledge, this is the first study to integrate Gene Expression Omnibus (GEO) datasets and supervised weighted correlation network analysis (sWGCNA) for defining TFs potentially related to CYPs/UGTs. We detected several novel TFs involved in the regulatory network of hepatic CYPs and UGTs in humans. Further validation and investigation may reveal their exact mechanism of CYPs/UGTs regulation. [ABSTRACT FROM AUTHOR]

We report on a facile method to detect the aggregation and co-aggregation of peptides by tryptophan fluorescence spectroscopy. Peptide aggregates (PAs) play a pivotal role in neurodegenerative diseases, such as Alzheimer's and Parkinson's. The detection of the formation of aggregates, especially in the early stage, will facilitate the diagnosis and treatment of the associated disease. In this study, by choosing a tryptophan-containing peptide of EP2, we investigated its fluorescence spectroscopic characteristics in the process of PAs. The results showed that the intensity of emission spectra was significantly enhanced with the formation of PAs within 48 h. In addition, by employing EP2 as a fluorescence probe, we found that EP2 was able to effectively monitor the aggregation of other peptides/proteins that are otherwise difficult to detect with conventional approach. Thus, these preliminary data provide a promising diagnostic tool to detect the formation of PAs. [Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]

The Hejiazhuang pluton is located in the South Qinling Tectonic Belt (SQTB) in the north side of the Mianxian-Lueyang Suture Zone, and consists dominantly of granodiorites. LA-ICP-MS zircon U-Pb dating and Lu-Hf isotopic analyses reveal that these granodiorites of the Hejiazhaung pluton emplaced at ∼248 Ma, and show a large variation in zircon ɛHf( t) values from −4.8 to 8.8. These granodiorite samples are attributed to high-K to mid-K calc-alkaline series, and characterized by high SiO (66.6%-70.0%), AlO (15.04%-16.10%) and NaO (3.74%-4.33%) concentrations, with high Mg# (54.2-61.7). All samples have high Sr (627-751 ppm), Cr (55-373 ppm) and Ni (17.2-182 ppm), but low Y (5.42-8.41 ppm) and Yb (0.59-0.74 ppm) concentrations with high Sr/Y ratios (84.90-120.66). They also display highly fractionated REE patterns with (La/Yb) ratios of 18.9-34.0 and positive Eu anomalies ( δEu=1.10-2.22) in the chondrite-normalized REE patterns. In the primitive mantle normalized spidergrams, these samples exhibit enrichment in LILEs but depletion in Nb, Ta, P and Ti. These geochemical features indicate that the granodioritic magma of the Hejiazhuang pluton was derived from the partial melting of hybrid sources comprising the subducted oceanic slab and sediments, and the melts were polluted by the mantle wedge materials during their ascent. The emplacement ages and petrogenesis of the Hejiazhuang pluton prove that the initial subduction of the Mianlue oceanic crust occurred at ∼248 Ma ago, and the SQTB was still under subduction tectonic setting in the Early Triassic. [ABSTRACT FROM AUTHOR]

Hemagglutinin (HA) is a membrane protein present on the influenza viral envelope. It is responsible for molecular recognition between the viral particle and the host cell, as well as fusion of the viral envelope to the endosome bilayer. Because it is essential for influenza viral infection and replication, it has become a target for the design of anti-influenza drugs. Previous studies have identified two small molecule HA ligands (CL-385319 and 1L) that inhibit infection with pseudovirus H5N1 with different potency. In order to compare their different inhibitory activities and shed light on drug design targeting the HA protein, we conducted a variety of theoretical calculations, including docking, molecular dynamics simulations, free energy calculations, as well as quantum calculations to investigate interactions between these two ligands and the HA protein. We found that molecule 1L has stronger π–π interactions with the side chains of residues F110 2 and M24 1 compared with molecule CL-385319. We propose that these stronger π–π interactions are responsible for the higher inhibitory activity of molecule 1L. Our calculations will aid drug design studies targeting the HA protein. [Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]

Mafic to felsic gneisses along the northern margin of the North China Craton (NMNCC), in western Liaoning province, China, were previously assumed to be part of Archean metamorphic basement but are here identified as younger (Permian-Early Triassic) intrusions. LA-ICP-MS zircon U-Pb isotopic dating reveals that the magmatic precursors of the mafic gneisses were emplaced from 295 ± 3 to 259 ± 2 Ma and that the magmatic precursors of the dioritic and monzogranitic gneisses were emplaced at 267 ± 1 and 251 ± 2 Ma, respectively, thus recording a continuum of Permian to Early Triassic magmatism. The mafic and dioritic rocks exhibit zircon ε( t) values from −20.7 to −3.3, suggesting they were mainly derived from a metasomatized lithospheric mantle source, possibly involving some crustal contamination. The monzogranitic rocks display their zircon ε( t) values of +0.9 to +4.7, indicating the acidic magma was derived from partial melting of juvenile crustal materials from the depleted mantle source. Crustal model ages ( T) obtained from zircon Hf isotopes of these monzogranitic rocks range from 976 to 1,215 Ma, with an average of 1,074 ± 32 Ma, possibly implying an episode of Grenvillian crustal growth in western Liaoning province. These new lines of evidence show that the NMNCC witnessed abundant magmatic activity and interaction of the crust and mantle during the Permian and Early Triassic and that the mafic magmatism was earlier than the monzogranitic activity. These findings indicate that the monzogranitic activity was the result of underplating of mafic magma with an enriched mantle source. In the context of regional Late Paleozoic to Early Mesozoic magmatic activity, the Permian magmatism occurred in an Andean-style continental margin setting when the Paleo-Asian oceanic plate was subducted beneath the NMNCC, and in this context, the Late Permian to Early Triassic magmatism may have been linked to post-collisional extension and asthenospheric upwelling, suggesting that the western Liaoning province in the NMNCC may be an eastward extension of the Late Paleozoic to Early Mesozoic active continental margin. [ABSTRACT FROM AUTHOR]

Covalent inhibitors form covalent adducts with their target, thus permanently inhibiting a physiological process. Peptide fusion inhibitors, such as T20 (Fuzeon, enfuvirtide) and C34, interact with the N-terminal heptad repeat of human immunodeficiency virus type 1 (HIV-1) gp41 glycoprotein to form an inactive hetero six-helix bundle (6-HB) to prevent HIV-1 infection of host cells. A covalent strategy was applied to peptide fusion inhibitor design by introducing a thioester group into C34-like peptide. The modified peptide maintains the specific interaction with its target N36. After the 6-HB formation, a covalent bond between C- and N-peptides was formed by an inter-helical acyl transfer reaction, as characterized by various biophysical and biochemical methods. The covalent reaction between the reactive C-peptide fusion inhibitor and its N-peptide target is highly selective, and the reaction greatly increases the thermostability of the 6-HB. The modified peptide maintains high potency against HIV-1-mediated cell-cell fusion and infection. [ABSTRACT FROM AUTHOR]

Fed-batch fermentation is the predominant method for industrial production of amino acids. In this study, we comprehensively investigated the effects of four kinds of feeding nutrients and developed an accurate optimization strategy for fed-batch production of l-threonine. The production of l-threonine was severely inhibited when cell growth ceased in the bath culture. Similarly, l-threonine production was also associated with cell growth in the carbon-, phosphate-, and sulfate-limited fed-batch cultures, but the accumulation of l-threonine was markedly increased because of the extended production time in the growth stage. Interestingly, auxotrophic amino acid ( l-isoleucine)-limited feeding promoted l-threonine production over the non-growth phase. Metabolite analysis indicates that substantial production of acetate and glutamate and the resulting accumulation of ammonium may lead to the inhibition of l-threonine production. During the growth phase, the levels of l-isoleucine were accurately optimized by balancing cell growth and production with Pontryagin's maximum principle, basing on the relationship between the specific growth rate μ and specific production rate ρ. Furthermore, the depletion of l-isoleucine and phosphate at the end of the growth phase favored the synthesis of l-threonine in the subsequent non-growth phase. Combining the two-stage feeding profiles, the final l-threonine concentration and conversion rate were increased by 5.9- and 2.1-fold, respectively, compared to batch processes without feeding control. The identification of efficient feeding nutrient and the development of accurate feeding strategies provide potential guidelines for microbial production of amino acids. [ABSTRACT FROM AUTHOR]

Evidence has shown that the p7, NS2 and NS3 genes affect the outcome of pegylated-IFN-α/ribavirin (PEG-IFN/RBV) combination therapy in different populations with HCV infections. Here, we test the hypothesis that diversity in the p7, NS2 and NS3 genes influences the probability of obtaining either a sustained (SVR) or non-sustained (non-SVR) viral response in Chinese patients with genotype 1b chronic hepatitis C. There were significantly more unique variations in the p7, NS2 and NS3 genes in the sequences from SVR than non-SVR patients. Inter-patient variations related to treatment outcome in NS3 were concentrated in the protease domain. There were no significant differences in the frequency of variations in the core, E1 and E2 proteins between the groups. In conclusion, increased amino acid sequence diversity in the p7, NS2 and NS3 genes is associated with an SVR to PEG-IFN/RBV therapy in Chinese patients with genotype 1b chronic hepatitis C. [ABSTRACT FROM AUTHOR]

l-Serine plays a critical role as a building block for cell growth, and thus it is difficult to achieve the direct fermentation of l-serine from glucose. In this study, Corynebacterium glutamicum ATCC 13032 was engineered de novo by blocking and attenuating the conversion of l-serine to pyruvate and glycine, releasing the feedback inhibition by l-serine to 3-phosphoglycerate dehydrogenase (PGDH), in combination with the co-expression of 3-phosphoglycerate kinase (PGK) and feedback-resistant PGDH (PGDH). The resulting strain, SER-8, exhibited a lower specific growth rate and significant differences in l-serine levels from Phase I to Phase V as determined for fed-batch fermentation. The intracellular l-serine pool reached (14.22±1.41) μmol g, which was higher than glycine pool, contrary to fermentation with the wild-type strain. Furthermore, metabolic flux analysis demonstrated that the over-expression of PGK directed the flux of the pentose phosphate pathway (PPP) towards the glycolysis pathway (EMP), and the expression of PGDH improved the l-serine biosynthesis pathway. In addition, the flux from l-serine to glycine dropped by 24%, indicating that the deletion of the activator GlyR resulted in down-regulation of serine hydroxymethyltransferase (SHMT) expression. Taken together, our findings imply that l-serine pool management is fundamental for sustaining the viability of C. glutamicum, and improvement of C units generation by introducing the glycine cleavage system (GCV) to degrade the excessive glycine is a promising target for l-serine production in C. glutamicum. [ABSTRACT FROM AUTHOR]

The mafic granulites in Dinggye, as various scale lense-shaped enclaves within the high Himalayan crystalline rock series, occur along mylonitic foliations at the junction between the Southern Tibetan Detachment System (STDS) and the Xainza-Dinggye normal fault system. The main lithological assemblage comprises garnet plagioclase pyroxenite, garnet two-pyroxene granulite, pyroxene garnet amphibolite and so on. The detailed petrological analyses show that these mafic granulites underwent at least four-stage metamorphic evolution. The first metamorphic stage, the garnet+clinopyroxene+quart mineral assemblage (M1) was probably formed under eclogite facies, the second stage, the plagioclase+clinopyroxene symplectite mineral assemblage (M2) was produced under high-pressure granulite facies by the early decompressive breakdown of M1 mineral assemblage, the third stage, the plagioclase+clinopyroxene+ hypersthene symplectite mineral assemblage (M3) was formed at granulite facies by the late period decompressive breakdown of M1 and M2 mineral assemblages and the final stage, pla-gioclase +hornblende mineral assemblage (M4) was formed by hydrolysis of earlier mineral assemblages during late uplifting. The detailed mineral composition analyses suggest that garnets and clinopyroxenes within M1 and M2 mineral assemblages display similar compositions to the equivalents in the B and C types of eclogites, whereas the M3 clinopyroxenes are akin to these of the same kind of minerals in the granulite. These mineral chemistry features and P-T estimates calculated by mineral thermometers and barometers indicate that the early stage relic porphyroblasts (M1) could be formed at the eclogite facies, the early decompressive breakdown (M2) occurred at the high-pressures granulite facies of 1.35–1.48 GPa and 625–675°C, the M3 mineral assemblage recorded the granulite facies of 0.7–0.95 GPa and 775–900°C and M4 plagioglase+hornblende retrograde mineral assemblage was produced under the amphibolite facies metamorphism with pressure of 0.4 to 0.75 GPa and temperature at between 660 and 700°C These construct P-T paths from crustal subduction overthickening to tectonic uplift tectonothermal evolution. The mineral chemical characteristics and P-T condition at every metamorphic stage of these granulites indicate that these rocks experienced the eclogite facies metamorphism during the early stage. Subsequently, these mafic granulites underwent the three-stage exhumation of the eclogite facies tectonic uplift, isostatic uplift related to the transformation from eclogite/high-pressure granulite to granulite facies and extensional uplift. [ABSTRACT FROM AUTHOR]

Metapelites from the Mesoproterozoic Xingxingxia group in the Eastern Segment of the Central Tianshan, Northwestern China, were analyzed for major and trace elements, including rare earth elements. Compared with post-Archean shales, the metapelites are enriched in Sr, Hf and Zr. The other elements are similar to the compositions of the Phanerozoic North American Shale Composite and the Post-Archean Australian average Shale (PAAS). The characteristics of Al2O3/TiO2, Cr/Zr, Cr/Th, Th/Sc and high Zr concentration suggest that these pelites could be derived from a significant proportion of felsic and a few proportion of participation of mafic materials in nature. These rocks display highly fractionated REE patterns, and average (La/Yb)n = 18.6. Several samples have slightly negative Eu anomalies (Eu/Eu* = 0.7 x 0.84) in comparison with PAAS (Eu/Eu* = 0.65), indicating contribution from young immature materials. The low K2O/Al2O3 values of these metapelites suggest that their source materials could contain minimal alkali feldspar. In the A-CN-K triangular diagram, the sample data array intersects the feldspar join, indicating that the source had a plagioclase: K-feldspar ratio of approximately 5:1, representing weathered products from components that could approximately correspond to granodiorites and tonalites. The low Chemical Index of Alteration (CIA) and high Index of Compositional Variability (ICV) values suggest low degrees of weathering of the source and low compositional maturity of the sediments, respectively. The geochemical characteristics of the metapelites from the Xingxingxia group also demonstrate that these sediments were deposited in a back-arc background within a continental-arc system. [ABSTRACT FROM AUTHOR]

SHRIMP U-Pb zircon analyses for a gabbro sample from the Garzê ophiolite block yielded a mean206Pb/238U age of 292 ±4 Ma, which indicated that the spreading time of the Garzê-Litang Tethys was most likely at the earliest Permian. Combined with previous studies, we suggest that the opening of the Tethys in southwest China was derived from breakup of the East Gondwanaland in the late Paleozoic. [ABSTRACT FROM AUTHOR]

Granitoid gneisses are widespread in Precambrian metamorphic blocks of eastern segment of the Central Tianshan Tectonic Zone, and they have intrusive contact relationships with their metamorphic sedimentary country rocks of Proterozoic Xingxingxia and Kawabulag groups. Zircon U-Pb ages from a granodioritic gneiss (IW11-1) and a parametamorphic schist (W05-9) are determined at the Weiya area. Euhedral prismatic zircons from the granodioritic gneiss (IW11-1) provide U-Pb isotopic discordia intercept ages of 1218∓17 Ma and 426∓26 Ma, respectively, and euhedral prismatic zircons from the parametamorphic schist (W05-9) display U-Pb isotopic discordia intercept ages of 1216∓74 Ma and 290∓15 Ma, respectively. A whole-rock Sm-Nd isotopic isochron is determined in augen granitoid gneiss samples at the Gang-gou-Kumishi area and we obtain the isochron age of 1142∓120 Ma, and its εNd(t) = −4.3. These geochronological data suggest that these Precambrian metamorphic basement blocks within eastern segment of the Central Tianshan Tectonic Zone can be produced during 1140-1220 Ma, and occur a nearly homochronous metamorphism. Integrated to these geochronological data, Nd depleted mantle model ages (TDm) and epsilon Nd(t) values of these granitoid gneiss samples indicate that they can derive from mixing in various scales both magmas from mantle and crust sources at a late Mesoproterozoic active continental margin tectonic environment. Similarity in geochronology, Sm-Nd isotopic geochemistry between Weiya-Xingxingxia, Pargangtag and Ganggou-Kumishi areas suggests that they could be a bigger uniform metamorphic basement block, which could be formed by the assembly of the supercontinent Rodinia and be separated by late geological processes. [ABSTRACT FROM AUTHOR]

There are five major geological events in Precambrian complex, Taihangshan region determined by researching into geology and isotopic chronology of the complex. Basaltic magma erupted and quartz-dioritic to tonalitic magma intruded in earlier neo-Archaean, which formed hornblende-plagiogneiss of Fuping gneiss complex and metamorphic mafic rock enclaves in TTGgneiss complex. Granulite facies metamorphism and emplacement of biotite-plagiogneiss occurred in late neo-Archaean. Extension and uplifting from the end of neo-Archaean to Paleoproterozoic era formed Chengnanzhuang large extensional deformation zones and metamorphic mafic veins emplaced into the deformation zones. Remobilization of Precambrian complex and tectonic uplifting in late Paleoproterozoic era formed Longquanguan ductile shear zone and emplacement of Nanying gneiss. Occurrence of regional granite pegmatite at the end of Paleoproterozoic era means the end of the Lüliang movement. gneiss complex. Granulite facies metamorphism and emplacement of biotite-plagiogneiss occurred in late neo-Archaean. Extension and uplifting from the end of neo-Archaean to Paleoproterozoic era formed Chengnanzhuang large extensional deformation zones and metamorphic mafic veins emplaced into the deformation zones. Remobilization of Precambrian complex and tectonic uplifting in late Paleoproterozoic era formed Longquanguan ductile shear zone and emplacement of Nanying gneiss. Occurrence of regional granite pegmatite at the end of Paleoproterozoic era means the end of the Lüliang movement. [ABSTRACT FROM AUTHOR]

Within the high-grade metamorphic basement, the central portion of North China Craton (NCC), a group of Neoarchean khondalites (KS) is identified. They are characterized by large ion lithophile elements (LILE) enrichment, lower abundances of Zr, Hf and Sr. Their rare earth element (REE) distribution has significant LREE enrichment and negative Eu anomalies. The protoliths of KS are interpreted as feldspathic quartzite, shale or pelite and carbonite, deposited in a shallow sea upon cratonic shelf distant from the land. KS’s source region might be dominated by granitic rocks, with a minor amount of TTG, underwent comparatively severe chemical weathering. Considering relevent tectonic constraints, we suggest that khondalites from central portion of NCC, an important metamophosed sedimentary cover, are the most significant exogenetic marker of Neoarchean continental cratonization for NCC. [ABSTRACT FROM AUTHOR]

The main problem, in determining the shear displacement of a general shear zone with volume change using the available formula, is that it is hard to know the initial angle between the planes (or lines) in the plane of shear. A planar deformation analysis of this kind of ductile shear zone is carried out with the polar Mohr diagram. If the volume change is induced by homogeneous contraction in the Z direction of the shear zone, there are sufficient conditions for constructing a polar Mohr diagram regardless of sequence of the simple shear and volume change. Therefore, the angle between a line and the shear direction before and after the deformation can be measured. Making use of these lines the shear strain and the volume change can be calculated and the shear displacement can be determined. [ABSTRACT FROM AUTHOR]

Investigates the P-T paths of the Xiaoqinling metamorphic core complex (XMCC) during epitope growth using the Gibbs method to compositional zones of epidotes of the XMCC. Thermodynamics processes experienced by XMCC; Possible role of the upweeling and emplacement of the deep magma.

The characters of fluid compositions and fluid-rock equilibrium system of the Archean Fuping gneiss complex, Taihang Mountains are first determined by fluid-rock equilibrium thermodynamics calculations and microthermometry of fluid inclusions. These investigations suggest that the X(H20) is generally less than 0.05 in fluids equilibrating with the granulite facies metamorphic mineral assemblage of Fuping gneiss complex, and fluid-rock interaction is chiefly controlled by C02-rich fluid infiltration. [ABSTRACT FROM AUTHOR]

This paper reported a wine-derived lactic acid bacterium, Lactiplantibacillus plantarum XJ25, which exhibited higher cell viability under acid stress upon methionine supplementation. Cellular morphology and the composition of the cytomembrane phospholipids revealed a more solid membrane architecture presented in the acid-stressed cells treated with methionine supplementation. Transcriptional analysis showed L. plantarum XJ25 reduced methionine transport and homocysteine biosynthesis under acid stress. Subsequent overexpression assays proved that methionine supplementation could alleviate the cell toxicity from homocysteine accumulation under acid stress. Finally, L. plantarum XJ25 employed energy allocation strategy to response environmental changes by balancing the uptake methionine and adjusting saturated fatty acids (SFAs) in membrane. These data support a novel mechanism of acid resistance involving methionine utilization and cellular energy distribution in LAB and provide crucial theoretical clues for the mechanisms of acid resistance in other bacteria., (© 2022. The Author(s).)