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Drawing on social exchange theory and institutional theory, this article extends the literature on sustainable operations by examining the mediating and moderating effects of buyer–supplier relation and institutional context on the relationships among internal green practice, external green practice, and environmental performance. This article analyzes data from 440 firms in three categories of market (the institutional context): industrialized Western, emerging Western, and emerging Asian markets. Both internal green practice and external green practice have positive direct impacts on firms’ environmental performance. More specifically and interestingly, external green practice partially mediates the relationship between internal green practice and environmental performance, and this process is moderated by the quality of the buyer–supplier relation. A higher quality of buyer–supplier relation helps to achieve a better outcome. In addition, the examined relationships vary between the emerging market and developed market: that is, they depend on the institutional context. The findings have implications for both practitioners and policymakers on how to improve environmental performance through leveraging green practice and buyer–supplier relation and what policies on green supply chain management might best be used in different markets.

Both continental crust and depleted mantle are characterized by subchondritic Nb/Ta, leading to a mass imbalance when compared to the bulk Earth. Even though several potential high-Nb/Ta reservoirs in Earth’s core and undepleted mantle have been proposed, little attention has been given to those in the crust. Here we present bulk-rock and rutile geochemical data for samples from a lower crustal pelitic granulite, North China Craton, which exhibit systematic variation in their Nb and Ta contents. High-temperature (HT) and ultrahigh-temperature (UHT) granulite residues exhibit Nb/Ta ratios that are close to chondritic and subchondritic, respectively, whereas leucosomes from UHT granulite mostly have suprachondritic Nb/Ta. These variations are best explained via competition for Nb and Ta between biotite and rutile during metamorphism, although initial bulk-rock Nb/Ta values also have an effect. As biotite preferentially incorporates Nb over Ta, the early stages of biotite dehydration melting produce a high-Nb/Ta residue and a low-Nb/Ta melt; however, geochemical modeling suggests that once biotite is depleted, the Nb/Ta ratio of the system is instead controlled by rutile growth, which promotes the formation of a lower Nb/Ta residue and a higher Nb/Ta melt, even though the volume of melt produced at this stage may be small. We propose that in situ and in-source leucosomes and leucocractic veins in UHT terranes may retain a high-Nb/Ta geochemical signature. However, residual crustal-derived A2-type granites that experience significant fractionation of Nb- or Ta-bearing minerals during crystallization or contamination from other low-Nb/Ta sources cannot retain this high-Nb/Ta ratio, even though these ratios are generally higher than that of S-type granites. Anhydrous partial melting of metapelite can generate Nb-rich melts, such that high-temperature leucosomes, in addition to related A2-type granites, may represent significant Nb deposits.

Earth’s earliest continental crust is dominated by tonalite–trondhjemite–granodiorite (TTG) suites, making these rocks key to unlocking the global geodynamic regime operating during the Archaean (4.0–2.5 billion years ago [Ga]). The tectonic setting of TTG magmatism is controversial, with hypotheses arguing both for and against subduction. Here we conduct petrological modeling over a range of pressure–temperature conditions relevant to the Archaean geothermal gradient. Using an average enriched Archaean basaltic source composition, we predict Ba concentrations in TTG suites, which is difficult to increase after magma generated in the source. The results indicate only low geothermal gradients corresponding to hot subduction zones produce Ba-rich TTG, thus Ba represents a proxy for the onset of subduction. We then identify statistically significant increases in the Ba contents of TTG suites worldwide as recording the diachronous onset of subduction from regional at 4 Ga to globally complete sometime after 2.7 Ga.

Ultra-high temperature (UHT) granulite-facies metamorphism is commonly identified in Mg–Al-rich rocks. Many such lithologies are thought to be metasedimentary rocks based on the presence of detrital zircon. However, whether a metasedimentary protolith is required to form diagnostic mineral assemblages and how much melt is lost during burial and heating to reach UHT conditions varies significantly according to the prograde pressure–temperature path. In this study, integrated thermodynamic modeling, accessory mineral modeling, and trace element modeling has been conducted on an average metapelite composition and average mid-ocean ridge basalt (MORB) composition under open-system conditions. The results show at least three and two melt loss events occur before reaching UHT conditions in initially water-saturated pelitic and basaltic rocks, respectively. Around 22–27 vol% S-type granite and 12–17 vol% I-type granite would be produced during these evolutions, respectively. Melt extraction leads to an increase of Al and Mg in metapelite residua. Mineral assemblage sapphirine + quartz is then allowed to form at higher grades; however, metabasalt does not form these UHT diagnostic assemblages, regardless of the amount of melt lost. During equilibrium melting, crustal differentiation induced by UHT metamorphism would significantly reduce the amount of heat-producing elements (HPEs) in the melt-depleted residuum, which progressively decreases a rock's heat production capacity. In reality, however, new monazite grains likely form during peak metamorphism and some monazite grains would be shielded by porphyroblasts, resulting in an increase of Th in the residua during heating. Even so, we suggest the efficiency of heat production would still decrease, given the heat production rate of Th is much lower than U. Considering some granitic rocks with relatively high heat production are emplaced into the granulite terrane, we suggest that radioactive heat production may be a contributing driving force for UHT metamorphism; however, it is not sufficient. Most heat required to generate UHT granulites must come from hybrid sources, such as advected heat from the mantle, conducted heat from nearby magmatic intrusions, radioactive heat production, and ductile shear deformation.

The emerging ligation-free three-dimensional (3D) genome mapping technologies can identify multiplex chromatin interactions with single-molecule precision. These technologies not only offer new insight into high-dimensional chromatin organization and gene regulation, but also introduce new challenges in data visualization and analysis. To overcome these challenges, we developed MCIBox, a toolkit for multi-way chromatin interaction (MCI) analysis, including a visualization tool and a platform for identifying micro-domains with clustered single-molecule chromatin complexes. MCIBox is based on various clustering algorithms integrated with dimensionality reduction methods that can display multiplex chromatin interactions at single-molecule level, allowing users to explore chromatin extrusion patterns and super-enhancers regulation modes in transcription, and to identify single-molecule chromatin complexes that are clustered into micro-domains. Furthermore, MCIBox incorporates a two-dimensional kernel density estimation algorithm to identify micro-domains boundaries automatically. These micro-domains were stratified with distinctive signatures of transcription activity and contained different cell-cycle-associated genes. Taken together, MCIBox represents an invaluable tool for the study of multiple chromatin interactions and inaugurates a previously unappreciated view of 3D genome structure.

The widespread spatio‐temporal occurrence of ultrahigh‐temperature (UHT) metamorphism in continental crust has been widely documented, but the heat source responsible for generating these extreme conditions over a short period of time remains enigmatic. Here, garnet orthogneiss, spinel‐bearing granulite, and gabbronorite from the east Khondalite belt, China, have been analyzed via integrated geochemistry, U‐Pb zircon isotope geochronology, and phase equilibria modeling to shed light on the timing and nature of rapid UHT metamorphism in this area. Peak metamorphism is characterized in garnet orthogneiss by the assemblage garnet + orthopyroxene + plagioclase + K‐feldspar + quartz, which is calculated to represent pressure–temperature conditions of 0.83–0.88 GPa at 930–990 °C. Zircon ages from this sample yield an igneous (protolith) emplacement age of approximately 1.93–1.95 Ga, which matches the timing of metamorphism in adjacent (pre‐UHT) metapelites. These garnet orthogneiss were then metamorphosed to UHT conditions at approximately 1.92 Ga, coincident with emplacement of mantle‐derived gabbronorites, as supported by REE patterns in zircon, and evidence for a rapid thermal pulse in the east Khondalite belt lower crust at that time. Heat‐source and heat‐transfer calculations indicate that advected heat from mafic magmas is the most likely cause of this regional‐scale event, although ductile shearing might have contributed to a lesser degree.

We report the results of a comprehensive isotopic investigation of zircons from metamorphosed orthogneisses from Caochang village in the Zunhua Complex, Eastern Hebei, North China Craton (NCC). A detailed investigation of the internal structures of these zircons combined with SIMS U–Pb and ICP-MS Lu-Hf zircon analyses, as well as a whole-rock geochemical study, revealed a previously unknown ∼2.9 Ga magmatic event in Eastern Hebei. The identified Mesoarchean gneisses are mainly felsic gneisses and amphibolites. Amphibolites with positive eNd(t) values were derived from the depleted mantle, with some crustal contamination during ascent. Zircon Hf isotopes indicate that the high-silica gneisses originate from the high-temperature mixing of mafic magma derived from a depleted mantle source and the subsequent felsic magma derived from the melting of ancient crustal materials, with the subsequent high degree fractional crystallization of the parental magma. Some of the 2.9 Ga felsic gneisses may record an anatectic event at 2.5 Ga. The widespread ancient inherited and detrital zircons (>2.6 Ga) and the existence of Mesoarchean rocks imply a possible ancient continent in Eastern Hebei. It may also imply that the Mesoarchean era (especially at 2.9 Ga) represents another important magmatic event in the eastern block of the NCC. The identification of 2.9 Ga rocks indicates that the magmatic history of Eastern Hebei is far more complex than previously thought.

Port traffic is affected by many factors, which may lead to certain problems in terms of maritime traffic safety and efficiency. To further study the maritime traffic flow of ships under the influence of multiple factors, our work combines artificial intelligence and an agent-based architecture to carry out port traffic flow simulation research. Moreover, considering an actual situation, a theoretical research method is used to analyze the feasibility of cellular automata combined with an agent architecture, and the basic framework is constructed. Simultaneously, in order to improve the computational efficiency, a system framework based on the Internet of Things structure is constructed, and the authenticity of the simulation process is improved. In addition, through a field investigation, the corresponding cellular automata model is established, and the cellular automata model and agent architecture are combined to establish the port traffic flow simulation model. Finally, the actual port operational data are collected to simulate various conditions, and the simulation results are obtained. The research shows that the model constructed in this paper has certain effects on the study of ship behavior in ports and can provide a theoretical reference for subsequent related research.

The Drosophila testis provides an exemplary model for analyzing the extrinsic and intrinsic factors that regulate the fate of stem cell in vivo. Using this model, we show that the Drosophila αTub67C gene (full name αTubulin at 67C), which encodes α4-Tubulin (a type of α-Tubulin), plays a new role in controlling the fate of male germline stem cells (GSC). In this study, we have found that Drosophila α4-Tubulin is required intrinsically and extrinsically for GSCs maintenance. Results from green fluorescent protein (GFP)-transgene reporter assays show that the gene αTub67C is not required for Dpp/Gbb signaling silencing of bam expression, suggesting that αTub67C functions downstream of or parallel to bam, and is independent of Gbb/Dpp-bam signaling pathway. Furthermore, overexpression of αTub67C fails to obviously increase the number of GSC/Gonialblast (GB). Given that the α-tubulin genes are evolutionarily conserved from yeast to human, which triggers us to study the more roles of the gene α-tubulin in other animals in the future.

The absence of ultrahigh pressure (UHP) orogenic eclogite in the geological record older than c. 0.6 Ga is problematic for evidence of subduction having begun on Earth during the Archean (4.0–2.5 Ga). Many eclogites in Phanerozoic and Proterozoic terranes occur as mafic boudins encased within low-density felsic crust, which provides positive buoyancy during subduction; however, recent geochemical proxy analysis shows that Archean continental crust was more mafic than previously thought, having greater proportions of basalt and komatiite than modern-day continents. Here, we show via petrological modelling that secular change in the petrology and bulk composition of upper continental crust would make Archean continental terranes negatively buoyant in the mantle before reaching UHP conditions. Subducted or delaminated Archean continental crust passes a point of no return during metamorphism in the mantle prior to the stabilization of coesite, while Proterozoic and Phanerozoic terranes remain positively buoyant at these depths. UHP orogenic eclogite may thus readily have formed on the Archean Earth, but could not have been exhumed, weakening arguments for a Neoproterozoic onset of subduction and plate tectonics. Further, isostatic balance calculations for more mafic Archean continents indicate that the early Earth was covered by a global ocean over 1 km deep, corroborating independent isotopic evidence for large-scale emergence of the continents no earlier than c. 3 Ga. Our findings thus weaken arguments that early life on Earth likely emerged in shallow subaerial ponds, and instead support hypotheses involving development at hydrothermal vents in the deep ocean.

Exercise is an effective way to alleviate insulin resistance (IR). However, the underlying mechanisms remain to be elucidated. Previous studies demonstrated that cardiolipin synthase 1 (CRLS1)/interferon-regulatory factor-2 binding protein 2 (IRF2bp2)-activating transcription factor 3 (ATF3)-adiponectin receptor 2 (AdipoR2)-adaptor protein containing pH domain, PTB domain and leucine zipper motif 1 (APPL1)-protein kinase B (AKT/PKB)-related signaling was closely associated with obesity-induced IR-related diseases, but the correlation between exercise training alleviating obesity-induced IR and the protein levels of hepatic CRLS1/IRF2bp2-ATF3-AdipoR2-APPL1-AKT-related signaling in rats is unknown. Therefore, We want to investigate the effect of exercise training on IR and the protein levels of hepatic CRLS1/IRF2bp2-ATF3-AdipoR2-APPL1-AKT-related signaling in rat.The male healthy Sprague-Dawley rats were divided into four groups: normal control group (NCG, n = 10), diet-induced obesity-sedentary group (DIO-SG, n = 10), diet-induced obesity-chronic exercise group (DIOCEG, n = 10) received chronic swim exercise training and diet-induced obesity-acute exercise group (DIO-AEG, n = 10) received acute swim exercise training. We measured the levels of IR-related indicators and the protein levels of hepatic CRLS1/IRF2bp2-ATF3-AdipoR2-APPL1-AKT-related signaling in NCG, DIO-SG, DIOCEG and DIO-AEG.We found that high-fat diet (HFD)-induced obesity decreased insulin sensitivity in rats accompanied by decreased protein levels of hepatic CRLS1, IRF2bp2, AdipoR2, APPL1, p-AKT and increased protein level of hepatic ATF3. The acute exercise and the chronic exercise both increased insulin sensitivity in rats. The chronic exercise decreased hepatic ATF3 protein level and increased CRLS1, IRF2bp2, AdipoR2, APPL1, p-AKT protein levels in HFD-fed rats. The acute exercise decreased hepatic ATF3 protein level and increased hepatic IRF2bp2, APPL1 and p-AKT protein levels in HFD-fed rats. The acute exercise had no significant effect on hepatic CRLS1 and AdipoR2 protein levels in HFD-fed rats.Our current findings indicated that exercise alleviated obesity-induced IR accompanied by changes in protein levels of hepatic ATF3-related signaling in rats. Our results are meaningful for exploring the molecular mechanism of exercise alleviating IR symptoms.

Tonalite–trondhjemite–granodiorite (TTG) gneiss forms a major component of Archean continental crust. Resolving the origin of TTG gneisses and the secular change in their compositions is critical for better understanding how the continental crust has evolved and when a global plate tectonic regime began on Earth. Archean TTGs were generated by partial melting of hydrous basalts, although the geodynamic setting in which this occurred is still debated. In this study, an integrated modeling including thermodynamic modeling, accessory mineral solubility modeling, and trace element modeling is conducted on Coucal basalts from Pilbara craton and averaged Archean arc-like basalts along various thermal gradients for both closed and melt-drained systems. The results show the amount and composition of melts would be primarily controlled by source compositions, although geothermal gradient and the ability for melt to leave the system also contribute. Of both bulk compositions, averaged Archean arc-like basalts generate more melts with a medium- to low-pressure signature by fluid-absent melting during intracrustal loading. High-pressure TTGs may be generated by mixing residua and melts derived by fluid-absent melting or just fluid-present melting in a hot subduction zone. Most TTGs produced before the Neoarchean were likely generated at the lower levels of thickened basaltic crust; however, rare Eoarchean and Mesoarchean TTGs with high-pressure signatures suggest subduction occurred on the early Earth in isolated localities. We interpret a secular increase in the proportion of high-pressure TTGs at c. 3.0–2.5 Ga as recording a transition from localized subduction to a global plate tectonic regime.

BACKGROUND Hepatitis B surface antigen (HBsAg) loss/seroconversion is considered to be an ideal endpoint for antiviral therapy and a final therapeutic target for chronic hepatitis (CHB). This study aimed to evaluate the HBsAg kinetics in CHB patients during peginterferon-alpha (Peg-IFN-alpha) treatment. MATERIAL AND METHODS A retrospective cohort study was performed using a case database, which included 151 patients who received Peg-IFN-alpha treatment and with HBsAg load of no less than 4 time points from May 1, 2018 to January 31, 2019. The HBsAg kinetic pattern was analyzed by Q-type clustering, and a clinical prognostic empirical model was constructed based on the HBsAg kinetic pattern of uncured patients. RESULTS Changes of HBsAg in 13 functionally cured patients were attributed to 3 kinetic patterns by cluster analysis, and there was a significant positive correlation between functionally cure time and baseline HBsAg. For uncured 116 patients with treatment duration longer than or equal to 56 days, 5 HBsAg kinetic patterns were obtained by cluster analysis, and the clinical prognosis empirical model was established. Finally, 13 new functionally cured patients preliminarily confirmed the rationality of the proposed empirical model. CONCLUSIONS According to empirical model, we recommend that the therapeutic regime should be timely adjusted to improve sustained response rate and reduce patients' medical burden for patients with second (Z type) and fifth (Z+W type) kinds of patterns. While for the rest of patterns' patients, it is recommended to continue treatment for a longer period of time to achieve the desired therapeutic goal.

Phytochemical investigations of the rhizomes of Smilax scobinicaulis led to the isolation of seven steroidal saponins ( 1 – 7 ) of which four ( 1 , 3, 4 and 6) , nameed, Smilscobinosides C-F, respectively) are new. Five of these steroidal saponins with l -arabinose moiety are reported here for the first time in the genus Smilax . The structures were elucidated by spectroscopic analysis of the isolates and their hydrolysis products. The isolated compounds were evaluated for their cytotoxicity against four human tumor cell lines (SH-SY5Y, SGC-7901, HCT-116 and Lovo). Compounds 3 and 4 exhibited significant inhibition on HCT-116 (with IC 50 values of 10.5 and 7.8 μM) together with inhibition on SGC-7901 (with IC 50 values of 21.4 and 15.8 μM), respectively.

The Barrovian metamorphic series represents a typical medium P/T regional metamorphism developed in pelitic lithologies, with metamorphic grades progressing from greenschist facies to granulite facies. As the metamorphic conditions are not too high in some lower-grade zones, some geological records of the prograde metamorphic stage may be well preserved. This is significant to the study of orogenic evolution. A sequence of Barrovian metamorphic series rocks from the garnet zone to the kyanite zone outcrops in the eastern part of Daqingshan terrane. An integrated study of petrography, phase equilibria modeling and zircon SIMS U–Pb geochronology is used to establish the P–T conditions and timing of this Barrovian metamorphism. Based on the petrology and mineral chemistry, minerals in each sample from different Barrovian metamorphic zones are divided into prograde, peak and retrograde metamorphic stages. Pseudosections are calculated using THERMOCALC for three samples from each zone, and the peak metamorphic conditions are confined to be 585 °C and 0.59 GPa for the garnet zone, 590 °C and 0.60 GPa for the staurolite zone, 645 °C and 0.71 GPa for the kyanite zone. The P–T paths of the Barrovian metamorphic rocks recorded a crustal over-thickening event during prograde metamorphic stage, and isobaric heating after reaching P max . The retrograde phase is characterized by cooling with decompression. Zircons from two higher metamorphic zones are dated using a CAMECA instrument. According to the results, the metamorphic ages of the different metamorphic zones are coeval and are estimated to be 1896 Ma. This is quite similar to the protolith age of the nearby arc-related Halaqin volcanic rocks. We suggest that the Daqingshan terrane experienced crustal thickening at 1896 Ma, with an arc magmatism superposition simultaneously.

Garnet is common in metamorphic rocks and can be used to efficiently constrain pressure–temperature conditions experienced during orogenesis; however, it may also crystallize as a primary phase in many types of magma, which can complicate deciphering the petrogenesis of meta-igneous rocks. In this study, geochronological and geochemical analyses of garnet and zircon were integrated to constrain garnet genesis in plagioclase-absent mafic granulite from the Jiao-Liao-Ji Belt, North China Craton. The rare earth element patterns show an equilibrium relationship between garnet and metamorphic zircon, indicating that garnet has a metamorphic origin. U–Pb dating shows that garnet has a whole-grain age of c. 1.83 Ga, with no difference between core and rim domains, which is slightly younger than metamorphic ages recorded by zircon (c. 1.87 Ga). The age difference between garnet and zircon is likely a result of differences in their closure temperature for the U–Pb isotope system. The mineral assemblage garnet + clinopyroxene + K-feldspar + titanite shows textural equilibration and was used to determine peak pressure–temperature conditions of 0.8–1.2 GPa at 830–880 °C. Given the age of high-pressure metamorphism (c. 1.87 Ga) calculated here being younger than c. 1.95–1.90 Ga proposed by previous studies for the west Liaodong peninsula, we suggest that c. 1.95–1.87 Ga represents the timing of progressive collision between the Longgang Block and the Nangrim Block, with the western part having collided slightly earlier than the eastern part.

Buying firms’ sales and reputation will be greatly damaged by any non-responsible behaviors on the part of suppliers, especially when those suppliers, like small and medium-sized enterprises (SMEs), have restricted resources and capabilities. To eradicate these risks, a growing number of buying firms have introduced socially responsible supplier development (SRSD). SRSD, including monitoring and evaluating suppliers, can provide them with incentives and assistance. Based on configuration theory and contingency theory, fuzzy-set qualitative comparative analysis (fsQCA) is adopted in this study to examine how SRSD practices adopted by buying firms, supply chain partnership, and market turbulence affect the corporate social responsibility (CSR) performance of their SME suppliers. We find that, as core factors, supplier monitoring, supplier assistance, and supply chain partnership can work together with peripheral conditions to achieve superior CSR performance. In addition, even at different levels of market turbulence, superior CSR performance can be realized through different causal configurations.