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Photodynamic therapy is known for its non-invasiveness to significantly reduce undesired side effects on patients. However, the infiltration and invasiveness of tumor growth are still beyond the specificity of traditional light-controlled photodynamic therapy (PDT), which lacks cellular-level accuracy to tumor cells, possibly leading to "off-target" damage to healthy tissues such as the skin or immune cells infiltrated. Here, upconversion nanoparticles (UCNPs) were co-encapsulated with manganese dioxide (MnO2) by amphiphilic polymers poly(styrene-co-methyl acrylate) (PSMA) and further coated with photosensitizer (riboflavin)-loaded mesoporous silica (C@S/V). The C@S/V nanoprobes exhibited shielded upconversion luminescence in normal conditions (pH 7.4, no hydroperoxide (H2O2)) under 980-nm irradiation and thus minimal reactive oxygen production from riboflavin. However, the excess H2O2 (1 mM) and acidic environment (pH 5.5) could decompose the MnO2 within the C@S/V, resulting in remarkable enhancement of upconversion luminescence and a favorable hypoxia-relieving condition for PDT, providing a spatiotemporal signal for therapy initiation. The C@S/V nanoprobes were applied to the co-culture of normal cells (HEK293) and pancreatic cancer cells (Panc02) and performed a selective killing on Panc02 under the 980-nm irradiation. By using the "double-safety" strategy, a responsive C@S/V nanoprobe was designed by the selective activation of acidic and H2O2-rich conditions and 980-nm irradiation for spatiotemporally selective photodynamic therapy with cellular-level accuracy. [ABSTRACT FROM AUTHOR]

Purpose and Methods: A global search for the lowest energy structure of CoB192− clusters was conducted. Results: Its ground state is a quasi-planar structure with the Co atom surrounded by a B8 ring. The central Co atom has an oxidation state of +1 with d8 electron configuration. The wave function analysis showed that the Co–B interaction is not a covalent bond. The bonding strength of peripheral B–B bonds is stronger than that of inner ones. The inner B8 ring bonds with outer boron atoms via σ- and π-type bonds. Conclusion: CoB192− shows remarkable aromatic character. [ABSTRACT FROM AUTHOR]

The genus Bambusa belongs to the subtribe Bambusinae and the subfamily Bambusoideae. The subgenera of Bambusa has not been satisfactorily circumscribed, and this remains a major taxonomic issue. Simultaneously, genera such as Dendrocalamus and Gigantochloa have not been confidently assigned to Bambusa. Here, the phylogenetic relationships among subgenera were investigated using five chloroplast DNA markers (rpl32-trnL, rpl16, matK, rbcL, and trnH-psbA) for a sample of 50 ingroup and 16 outgroup species. A total of 186 key morphological descriptors were studied for the 50 ingroup species. The results indicated that five chloroplast DNA markers were possible to distinguish Bambusa species from other species and divide them into several clusters. Phylogenetic analyses conducted using morphological descriptors and a combined marker (rpl32-trnL+rpl16) revealed three and five distinct lineages, respectively, among the currently recognized Bambusa species. The branching pattern of the dendrogram was not completely consistent with the classical taxonomic classification of Bambusa. In addition, not all varieties and cultivars were clustered with McClure classifications. As the maximum parsimony topology and morphological analyses were inconsistent, some clustering results overlapped. Overall, the results obtained here do not support the current classification of the Bambusa subgenera. [ABSTRACT FROM AUTHOR]

A novel nanoassembly was constructed through encapsulating upconversion nanoparticles (UCNPs) into a metal–organic framework structure (ZIF-8), in which doxorubicin (DOX) was absorbed into pores of ZIF-8. The blue emission of UCNPs was quenched by DOX through the fluorescence resonance energy transfer (FRET) strategy. When the nanoprobe was exposed to food samples with different pH values, ZIF-8 collapsed to release DOX molecules, resulting in upconversion recovery. The porous structure of ZIF-8 provides abundant space for DOX absorption, which significantly improves the detection capacities and accuracy. It is shown that the probe has a good linear relationship when pH values vary from 2.5 to 7.4, and can distinguish pH variations as low as 0.5 in real samples. This strategy has been successfully used to determine food spoilage by determination of pH variations. [ABSTRACT FROM AUTHOR]

The salt-tolerant variety Chuanqiao No.1 and salt-sensitive variety Chuanqiao No.2 of Tartary buckwheat were used as experimental materials. The effects of exogenous calcium on physiological characteristics and the expression of salt tolerance related genes in Tartary buckwheat were analyzed. The results showed that under salt stress, treatment with the appropriate concentration of calcium was beneficial to improve the seed germination rate and seedling fresh weight of Tartary buckwheat, the salt-sensitive variety was increased more, significantly increased the leaf chlorophyll content of Tartary buckwheat, the salt-tolerant variety was increased more, and significantly reduced the leaf MDA content of Tartary buckwheat, the salt-tolerant variety was decreased more. The appropriate concentrations of calcium for Chuanqiao No.1 and Chuanqiao No.2 were 30 mM and 20 mM, respectively. Treatment with the appropriate concentration of calcium could significantly promote the expression of Ca2+-ATPase gene and CBL interaction protein related genes in the stem of salt-sensitive variety and the root of salt-tolerant one, and that of CaMK gene in the stem of salt-tolerant variety. The effects of exogenous calcium treatment on physiological characteristics varied obviously between salt-tolerant and salt-sensitive varieties of Tartary buckwheat. [ABSTRACT FROM AUTHOR]

An intriguing solid-state all-carboatomic ring, cyclo[18]carbon was observed recently in experiment. In this paper, the structures, bonding characters and electronic properties of Be- and Mg-doped cyclo[18]carbon ( BeC 18 and MgC 18 ) were studied using density functional theory. The most stable structures of BeC 18 and MgC 18 are still ring-like configurations. Bond order analysis shows the characteristic of alternative bond length for the doped C 18 . Compared with primitive C 18 ring, the long C–C bond length of doped C 18 became longer and the bond order became smaller on the whole. However, the short C–C bond gets shorter and the bond order gets larger. The features of frontier molecular orbital of BeC 18 and MgC 18 were different from that of primitive C 18 . The results of bond order, electron difference density, localized orbital locator, binding energies and metal–carbon bonding interactions revealed that the structure of BeC 18 is more stable than MgC 18 . Both BeC 18 and MgC 18 are weak aromaticity. [ABSTRACT FROM AUTHOR]

The use of lignocellulosic materials for extracting functionalized cellulose nanocrystals (FCNs) in a green and sustainable method under mild conditions is limited owing to the strong hydrogen bonding in cellulose. A facile, green, and high-efficient avenue was developed to produce FCNs with high yield through the mechanochemistry synergetic effect of recyclable p-toluenesulfonic acid (PTSA)-catalyzed deep eutectic solvent (PDES) and microwave- solvothermal (MWS). FCNs with a high charge density of 1.59 e nm−2, a crystallinity of 81%, a better thermostability and dispersibility were obtained at a high yield of 87.6% by the one-step processing. The PDES could be easily recycled, and thus was beneficial to cost reduction and waste liquor treatment. Generated FCNs could be used to develop functional bionanocomposites due to their enhanced effect. When a loading of 1 wt% FCNs was added into gelatin matrix, the tensile strength and Young's modulus of the bionanocomposites increased 188 and 131%, respectively, suggesting their remarkable stress transfer potential. Thus, the study demonstrates a green and cost-effective approach for the mass production of FCNs, contributing to strong potential in building high-performance bionanocomposites. [ABSTRACT FROM AUTHOR]

Background: The prevalence of carbapenemase-producing organisms (CPOs) globally poses a public health threat; however, detecting carbapenemases is a challenge because of their variety. Methods: GENECUBE, a fully automated gene analyzer, detects a target gene in a short time and simultaneously detects its single nucleotide polymorphism. We used this property to develop for the first time a rapid assay for detecting CPOs from cultured bacteria using GENECUBE. The original primer-probe sets were used to detect blaKPC, blaIMP, blaVIM, blaNDM, and blaOXA-48-like from 149 CPOs (nine types) and 61 non-CPOs. Results: The sensitivity, specificity, and positive and negative predictions of the GENECUBE assay were 100%. This assay detected carbapenemase single-producers and carbapenemase co-producers with 100% accuracy. The time required for detects of four types of carbapenemase at one run was about 30 min, but it took about 1 h to detect all five types. In addition, this assay performed the rapid detection and classification of blaOXA-48, blaOXA-181, blaOXA-232, and blaOXA-244 simultaneously. Conclusions: The GENECUBE assay is a promising tool for controlling the spread of CPOs and helping to select accurate and rapid antibiotic therapies. [ABSTRACT FROM AUTHOR]

In this paper, the effect of two-phase interface morphology evolution on the flow and heat transfer characteristics in confined channels are reviewed in detail, which is one of the typical channel structures for the nuclear reactor core. The investigated contents mainly come from the open literature. In addition, this paper focuses on the important phenomena and methods proposed in recent decades, which simultaneously includes the closely related studies of authors published in the last several years. The primary contents of this paper mainly includes the following aspects: (1) the definition of confined channel is introduced based on the summary of various distinguishing criterions; (2) the effect of two-phase interface morphology on the flow and resistance characteristics is concluded, which are mainly related to the adiabatic flow conditions, thus the complex influence of boiling phenomenon can be neglected; (3) the effect of two-phase interface morphology on the flow boiling heat transfer characteristics is researched. Moreover, the development of flow boiling heat transfer model is reviewed, and the corresponding proposed model is introduced, which innovatively reflects the feature of confined channel and is considered worthy of further development; (4) the effect of two-phase interface morphology on the flow instability and boiling crisis characteristics are reviewed. Especially, the coupling relationship between them are introduced with the bubble dynamic behaviors dependent on the published research achievement of authors; (5) the material surface modification technology is proposed to be the enhanced heat transfer technology, which is also supposed to be the future research point for reactor thermal-hydraulics. [ABSTRACT FROM AUTHOR]

Highlights: Nanomaterials-based nickel foam (NF-C/CoS/NiOOH) with nanosheets structure and core–shell heterostructure was prepared for the first time by a facile and fast synthesis strategy of Joule-heating and water soaking treatment. The formation mechanism of nanosheets structure was proposed that the driving force of nanosheets structure generation was the metastable nickel activated by thermal shock, and the CoS could induce the NiOOH nanosheets growing continually. NF-C/CoS/NiOOH exhibited good oxygen evolution, hydrogen evolution, and overall water splitting performance. Nanomaterials based on nickel foam (NF) have been widely applied in energy conversion and storage field. Traditional synthesis methods such as hydrothermal method which is dangerous and high cost limited the scalable developments. Herein, we report a fast, simple, and low-cost synthesis method of nanomaterials based on NF by Joule-heating and water soaking treatment. Thin carbon-coated CoS on NF (NF-C/CoS) was synthesized by Joule-heating for a few seconds with rapid cooling. And then, NF-C/CoS/NiOOH with core–shell heterostructure was fabricated by soaking treatment of NF-C/CoS in water on which NiOOH nanosheets grew spontaneously. The formation mechanism is proposed that the coordination complex precursor converts into C/CoS on NF driven by Joule-heating, and the nickel on the surface of NF is activated to form metastable nickel simultaneously. The metastable nickel reacting with water leads to the formation of NiOOH, and the induction of CoS makes NiOOH grow continuously. This synthesis technology provides a new route to manufacture NF-based nanostructures, and the as-fabricated NF-C/CoS/NiOOH exhibits great potential as electrocatalyst for oxygen evolution reaction and hydrogen evolution reaction. [ABSTRACT FROM AUTHOR]

Numerous studies related to the simulation and prediction of urban growth to address land-use and land-cover (LULC) changes have been conducted in recent years, but very few have considered the impact of climate change, flooding impact, government relocation, corridor cities, and long-term rainfall variations simultaneously. To bridge the gap, this study predicts possible future LULC changes for 2030 and 2050 in Beijing (China), since Beijing is one of the fastest-growing megacities in the world. The proposed integrated modeling analysis covers four key scenarios to reflect the influences of different factors and constraints on LULC changes, in which cellular automata, Markov chain, and multi-criteria evaluation are fully coupled. While fuzzy membership function was used to address the uncertainty associated with the decision analysis, Markov chain, which is regarded as a stochastic process, was applied to predict future urban growth pathways. In addition, a statistical downscaling model driven by possible climate change scenarios was employed to address long-term rainfall variations in Beijing, China. This study differs from previous ones for Beijing in terms of not only the effects of climate change and flooding impact but also the newly-developed economic free trade zone in Xiong’an and the central government’s plan to relocate to the Tongzhou district. Findings indicate that there is no marked difference in LULC over the four key scenarios. Compared to the baseline LULC in 2010, the predicted results indicate that urban expansion is expected to increase more than 6 and 11% in 2030 and 2050, respectively. [ABSTRACT FROM AUTHOR]

Ionic liquids-based solid polymer electrolytes enhance the battery’s overall performance without drawbacks in safety compared with conventional electrolyte. In order to develop a novel solid electrolyte, we synthesized a series of novel room temperature imidazolium-based polyhedral oligomeric silsesquioxane ionic liquids (POSS-ILs) consisting of POSS-COO− anions and a variety of imidazolium cations, which will be used as plasticizers of solid polymer electrolyte in this work. The thermal stabilities of POSS-ILs have been dramatically enhanced by the introduction of POSS moiety, and the initial decomposition temperatures of POSS-ILs have increased by at least 94 °C compared to their corresponded succinamic acid ionic liquids. The glass transition temperatures of POSS-ILs also have increased to − 15.9 to − 25.4 °C. Then the POSS-ILs are employed to obtain a novel solid polymer electrolyte based on blend of polyethylene oxide, poly(vinylidene fluoride-hexafluoropropylene), propylene carbonate and lithium bis(trifluoromethanesulfonyl) imide with high ionic conductivity and electrochemical windows. The ionic conductivities of POSS-ILs-based solid polymer electrolytes are up to 8.0 × 10−4 S cm−1 at 22 °C and 2.0 × 10−3 S cm−1 at 62 °C, and the electrochemical windows of POSS-ILs-based solid polymer electrolytes are stable up to 5.0 V. Moreover, the Li/LiFePO4 cell containing POSS-ILs-based solid polymer electrolytes exhibits good cycling performance and high rate stability. These results suggest that the POSS-ILs-based solid polymer electrolytes could be a suitable prospective electrolyte material for lithium-ion battery applications. [ABSTRACT FROM AUTHOR]

With the rapid development of manufacturing industry, carbon emissions have risen year by year within the global environment. As we know, the equipment manufacturing product, i.e., machine tool, which is broadly used in the machining process, produces large amounts of carbon emissions in the usage stage. Low-carbon design is an effective way to reduce carbon emissions through optimization and improvement of some certain parts or components. Because the carbon emissions of the equipment manufacturing product are the joint result of all parts in the usage stage, how to estimate and allocate carbon emissions to these parts or components to be optimized, which are defined as the target parts or components, is becoming the bottleneck. Therefore, this paper presents an allocation method of carbon emissions based on the product's temperature field to support the low-carbon design. Firstly, the boundary model and calculation method are proposed based on a concept of 'embodied carbon-energy (ECE)' to provide carbon emissions data. Secondly, some key factors influencing energy consumption in the usage stage are analyzed based on an exergy analysis approach. Thirdly, an allocation model of carbon emissions based on the temperature field is established. Finally, the proposed model and method are applied to a honing head component to validate their feasibility and correctness. The result shows carbon emissions of the usage stage have a close connection with the temperature distribution and gradient, so the temperature field can be used to allocate carbon emissions effectively. In addition, the effective allocation method provides a theoretical basis for the target parts or components decision in the low-carbon design. [ABSTRACT FROM AUTHOR]

Both arrangement and modification of dimples have significant effects on flow and heat transfer performance and the local high-temperature spots (hot spots) risk on the channel walls, which could potentially cause irretrievable damages to the high-power heat source, due to the negative effect on heat transfer of low velocity "dead zone" in the wake region for traditional dimples. To this end, the narrow rectangular channel with elliptic dimples with different rotated angles ranging from 0° to 90° are firstly systematically studied to explore the mechanism of balance of average and local heat transfer performance and flow resistance to figure out the most appropriate rotated angle. In order to further minimize the hot spot risk, novel dimples with streamwise/inclined slit are proposed and numerically studied to explore the dissipation of recirculation region or low velocity "dead zone" through the slit inducing a stream of flow from the front region to the wake region. In evaluation of the hot spot risk, the new indicator of high temperature probability (HTP) is proposed as a critical indicator. Compared to the channel with traditional dimples, slit can effectively reduce local high temperature and pressure loss by inducing a stream of flow from the front region to the wake region. Compared with the streamwise slit, the inclined slit performs better both in heat transfer performance and HTP. Compared with the smooth channel, the average heat transfer coefficient of the channel with inclined slit dimples with rotated angle of 75° can be the improved by up to 14%, the maximum temperature of the channel wall can be decreased by up to 6.78 K and HTP of the channel wall can be decreased by up to 14.21%. [ABSTRACT FROM AUTHOR]

A series of monodispersed (PDI <0.05) butyl acrylate emulsions with different sizes (100-500 nm) and solid contents (22, 17, 12 and 7 wt%) were prepared using a semibatch seeded emulsion polymerization method. Sodium dodecyl sulfate (SDS) was used as an emulsifier and potassium persulfate as an initiator. Surface tensions of the emulsions were investigated and the relationship of the emulsion stability, particle size and solid content was examined. The critical micelle concentration (CMC) of the emulsifier SDS was determined by the intersection of two tangents to surface tension curves. We found that the surface tension at CMC as high as 65.99 mN/m for the emulsion with a solid content of 22 % and a particle size of 115 nm, very close to the value of it for pure water. The surface tension decreased from 65.99 to 54.74 mN/m with an increase in particle size from 115 to 494 nm concomitantly with a decrease in the CMC of SDS from 56.10 to 19.83 mmol/l for the emulsion with a solid content of 22 wt%. As to the emulsions with the same particle size, CMC value was positively correlated with solid content. The minimum value of CMC was 9.12 mmol/l for the emulsion with a solid content of 7 % and a particle size of 494 nm, whereas the maximum CMC was 56.10 mmol/l for the emulsion with a solid content of 22 wt% and a particle size of 115 nm. As a result, an equation describing the relationship between CMC and solid content was deduced. This model yielded the same trends as the experimental results. [ABSTRACT FROM AUTHOR]

Aerostatic bearings are the key component of ultra-precision machine tools, and the bearing performance is critical to the machining accuracy and reliability. The characteristics of the air film pressure field (AFPF) mainly determine the bearing performance and are closely related to parameters such as the air supply pressure, the number, and position distribution of orifices. However, the orifices of aerostatic bearing were usually assumed to be ideal for the available related research. The phenomenon of orifice blockage is common in the actual working conditions, which has great impact on the bearing performance. In this study, the AFPF characteristics of aerostatic thrust bearing was analyzed by the theoretical and experimental way with the commonly single-orifice blockage (SOB) or double-orifice blockage (DOB) cases. The air film pressure distribution, load capacity, and tilting moment are obtained for each case. The effectiveness of simulation results is verified by the experiments. The results indicates that the air film pressure decreases significantly in the area of about three orifices adjacent to the blocked orifice in the condition of SOB. Different cases of orifice blockage have different bearing tilting moment, and resulting in different bearing tilting angle. According to different bearing tilting direction and tilting angle, a preliminary prediction method of the orifice blockage is proposed to judge the different cases of orifice blockage. [ABSTRACT FROM AUTHOR]

Highlights: Nanomaterials-based nickel foam (NF-C/CoS/NiOOH) with nanosheets structure and core–shell heterostructure was prepared for the first time by a facile and fast synthesis strategy of Joule-heating and water soaking treatment. The formation mechanism of nanosheets structure was proposed that the driving force of nanosheets structure generation was the metastable nickel activated by thermal shock, and the CoS could induce the NiOOH nanosheets growing continually. NF-C/CoS/NiOOH exhibited good oxygen evolution, hydrogen evolution, and overall water splitting performance. Nanomaterials based on nickel foam (NF) have been widely applied in energy conversion and storage field. Traditional synthesis methods such as hydrothermal method which is dangerous and high cost limited the scalable developments. Herein, we report a fast, simple, and low-cost synthesis method of nanomaterials based on NF by Joule-heating and water soaking treatment. Thin carbon-coated CoS on NF (NF-C/CoS) was synthesized by Joule-heating for a few seconds with rapid cooling. And then, NF-C/CoS/NiOOH with core–shell heterostructure was fabricated by soaking treatment of NF-C/CoS in water on which NiOOH nanosheets grew spontaneously. The formation mechanism is proposed that the coordination complex precursor converts into C/CoS on NF driven by Joule-heating, and the nickel on the surface of NF is activated to form metastable nickel simultaneously. The metastable nickel reacting with water leads to the formation of NiOOH, and the induction of CoS makes NiOOH grow continuously. This synthesis technology provides a new route to manufacture NF-based nanostructures, and the as-fabricated NF-C/CoS/NiOOH exhibits great potential as electrocatalyst for oxygen evolution reaction and hydrogen evolution reaction. [ABSTRACT FROM AUTHOR]

The objective of the study was to evaluate the contribution of insulin resistance and β cell dysfunction to gestational diabetes mellitus (GDM) in Chinese women stratified by pre-pregnant body mass index (BMI). A total of 847 pregnant women were enrolled. They were divided into low BMI and high BMI groups according to the median of pre-pregnancy BMI. The homeostasis model assessment of insulin resistance (HOMA-IR) and β cell function (HOMA-β), Matsuda index, and 60-min insulinogenic index (IGI60) were used to evaluate insulin resistance and β cell function. In all the participants, 150 (17.71%) were diagnosed with GDM. ROC analyses showed that in the low BMI group, the association of β cell dysfunction (IGI60 or HOMA-β) with GDM was stronger than that of insulin resistance (Matsuda index or HOMA-IR), while in the high BMI group, the association of β cell dysfunction with GDM was weaker than that of insulin resistance (all P < 0.05). Among all GDM patients, 47.33% demonstrated predominant insulin resistance (Matsuda index < 25th percentile), and 46% had predominant β cell defect (IGI60 < 25th percentile). In the low BMI group, 15.09% of GDM patients demonstrated predominant insulin resistance, and 62.26% of GDM patients had predominant β cell defect, whereas in the high BMI group, 64.95% of GDM patients demonstrated mainly insulin resistance and 36.08% of GDM patients had mainly β cell defect. In women with low BMI, β cell dysfunction is the major etiologic factor, whereas, in women with high BMI, insulin resistance is the predominant etiologic factor in the development of GDM. [ABSTRACT FROM AUTHOR]

Based on virtualization technologies, virtual machines (VMs) provide computing services and network resources for cloud users over the Internet. When cloud users use VMs for an extended period of time, requests generated by other cloud users are easily blocked. When cloud users no longer use VMs, requests' throughput will be decreased substantially. We propose a multi-input cloud resource allocation strategy with limited buffer and VM synchronization failure, which can improve the throughput of requests. A limited buffer is added to the system to reduce the possible blocking behaviors in the proposed strategy. Moreover, we assume that a physical machine failure will put all the VMs in failure states. The system recovery will take a period of time after the failure, which is called repair time. After the failure is repaired, the system continues to provide services for cloud users. A 2-dimensional Markov chain is established to measure the performance indexes of requests. In addition, we show the blocking rate, the loss rate, the throughput, the average quantity, and the average latency of requests by system state transition probability matrix and analyze their changing trends through numerical experiments. Finally, considering the balance between requests' blocking rate and requests' throughput, we construct a system profit function to ascertain the optimal number of request streams and obtain the maximal system profit. [ABSTRACT FROM AUTHOR]

Previous studies have regarded the discriminatory serum β-hCG zone (DSZ) as a valuable tool for the diagnosis of ectopic pregnancy (EP). However, the wide range of the DSZ makes achieving a clinical diagnosis of EP difficult, and these reports do not indicate whether the DSZ is suitable for an EP diagnosis in Chinese women. Several studies have indicated that the endometrial pattern in patients with EPs is different from that in patients with intrauterine pregnancies (IUPs). The aims of this study were to define the DSZ cutoff value for Chinese women, test whether the endometrial pattern is a suitable predictor for EP, and assess the diagnostic value of these indicators. We enrolled participants with IUPs or EPs with abdominal pain and/or vaginal bleeding, and serum β-hCG level measurements and transvaginal ultrasound (TVS) were performed to assess the diagnostic value of the indicators for EP. The sensitivity and specificity for identifying an EP were improved by combining the DSZ, endometrial thickness and trilaminar pattern indexes. The results of this study might be helpful toward providing further options for the diagnosis of EP, especially for patients without hemoperitoneum or colporrhagia. [ABSTRACT FROM AUTHOR]

Neurodegenerative diseases all share several common features such as involvement of oxidative damage and mitochondrial dysfunction in pathogenesis. Oxidative stress induced by overproduction of mitochondrial reactive oxygen species (ROS) or impairment of the antioxidant deficiency results in mitochondrial dysfunction and initiation of the cell death cascade. Berberine (BBR), a traditional Chinese medicine, has been reported to exert anti-oxidative stress and anti-apoptosis effect in CNS diseases. However, the mechanism of BBR on regulating mitophagy and protecting mitochondrial function under oxidative stress remains unclear. In present study, we evaluated the beneficial effects of BBR on the tert-butyl hydroperoxide (t-BHP)-induced cytotoxicity. Furthermore, we explored the protective role of BBR in mitochondrial function and mitophagy under oxidative stress in PC-12 cells. Our results demonstrated that BBR effectively inhibited t-BHP-induced apoptosis which is associated with the decreased leakage of lactate dehydrogenase (LDH) and ROS overproduction. Moreover, BBR significantly suppressed cytochrome c expression, upregulated the ratio of Bcl-2/Bax, and ameliorated mitochondrial dysfunction by optimizing mitochondria membrane potential (ΔΨm) status and ATP production. In addition, BBR reduced the expression of autophagy-specific marker LC3, SQTM1/p62, and maintained lysosome normal function which involved the restoration of upstream signaling pathway AKT and mTOR phosphorylation level. Collectively, these findings suggested that BBR protects PC-12 cells from oxidative injury through inhibiting ROS level, mitochondria dysfunction, and mitophagy via PI3K/AKT/mTOR signaling pathways, which suggest a potential therapeutic strategy for oxidative stress and neurotoxic damages. [ABSTRACT FROM AUTHOR]

Abstract: A global search for the lowest energy structure of B20Si−, B20Si0 and B20Si+ clusters is conducted. Structural transitions at different charge states are observed. B20Si− is a 2D planar configuration with no polygonal holes, and Si atom occupies a peripheral position. B20Si+ adopts a 3D tubular shape, and each Si is bonded with four B atoms. But for B20Si0, competition among quasi-planar, tubular and cage like structures is found. These structures differ greatly from that of pure B21− cluster. The structural transition may result from changes in the framework of bonding, sp2 hybridization, and structural mechanics. Some of the clusters’ properties including frontier molecular orbital, on-site charge on Si atom, electron density, and magnetism are also discussed. Graphical abstract: [ABSTRACT FROM AUTHOR]

Purpose: Compared with people without diabetes, people with type 2 diabetes (T2D) are at higher risk of both subnormal vitamin C status and increased oxidative stress. We aimed to investigate the associations of serum vitamin C concentrations with all-cause and cause-specific mortality among adults with and without T2D. Methods: The current analysis included 20,045 adults (2691 people with T2D and 17,354 without T2D) from the Third National Health and Nutrition Examination Survey (NHANES III) and NHANES 2003–2006. Cox proportional hazards regression models were applied to estimate hazard ratios (HRs) and 95% confidence intervals (CIs). Restricted cubic spline analyses were used to examine the dose–response relationship. Results: After a median follow-up of 17.3 years, 5211 deaths were documented. Individuals with T2D had a lower level of serum vitamin C concentrations compared with those without T2D (the median value: 40.1 vs. 44.9 μmol/L). Furthermore, the dose–response relationship between serum vitamin C and mortality showed different patterns between participants with and without T2D. In individuals without T2D, there was a nonlinear association of serum vitamin C concentrations with all-cause, cancer, and CVD mortality, with the lowest risk around a serum vitamin C concentration of 48.0 μmol/L (all Poverall < 0.05, Pnonlinearity < 0.05). In contrast, among those with T2D in the similar concentration range, higher serum vitamin C levels (ranged from 0.46 to 116.26 μmol/L) were linearly associated with lower all-cause and cancer mortality (both Poverall < 0.05, Pnonlinearity > 0.05). Significant additive interaction was observed between diabetes status and serum vitamin C levels with regard to all-cause and cancer mortality (P < 0.001). In addition, C-reactive protein, gamma-glutamyl transpeptidase, and HbA1c explained 14.08, 8.96, and 5.60% of the association between serum vitamin C and all-cause mortality among individuals with T2D, respectively. Conclusions: Higher serum vitamin C concentrations were significantly associated with lower risk of mortality in participants with T2D in a linear dose–response manner, while a nonlinear association was observed in participants without T2D, with an apparent threshold around 48.0 μmol/L. These findings suggest that the optimal vitamin C requirement may differ in individuals with and without T2D. [ABSTRACT FROM AUTHOR]

In this article, we focus on a design problem of flow distribution structure in nuclear reactor pressure vessel within the meshless topology optimization framework. A novel meshless particle method, NURBS-based particle hydrodynamics (NBPH) method, is proposed. And a meshless CFD computational model based on NBPH is presented to analyze the coolant flow field in pressure vessel. Comparing the results of NBPH with those of FVM in Fluent, we conclude that the proposed method can not only obtain physical field solution with high accuracy, but also has high computational efficiency. By coupling the NBPH method with the solid isotropic material with penalization (SIMP) method, a unique NBPH-TO structure design platform is constructed, in which the communication between the meshless solver and the mesh-based optimizer is accomplished by solving the transient sensitivities and constructing a voxel-based friction field. Two structure designs with opposite flow distribution objectives are investigated in the paper to demonstrate the effectiveness and robustness of the NBPH-TO structure design platform. The design cases show that the constructed NBPH-TO framework can obtain the optimal topology stably. This is the first attempt to apply the meshless topology optimization method to the design of the internal structure of the lower chamber of a pressure vessel. The research provides a viable solution and an effective tool for design of structures within nuclear reactor pressure vessels. [ABSTRACT FROM AUTHOR]

Considering the complexity and diversity of cloud requests in the cloud environment, cloud requests are divided into primary requests (PRs) with high priority and secondary requests (SRs) with low priority. We introduce the entry threshold and the entry probability to control the entry of SRs. If the number of busy virtual machines (VMs) is greater than or equal to the entry threshold, the recently arrived SR will enter the system with an entry probability that is inversely proportional to the number of busy VMs. Based on the proposed cloud resource allocation strategy with entry control, a discrete-time queueing model is constructed, and the expressions of performance indicators are derived. Compared with the conventional cloud resource allocation strategy without entry control, the proposed cloud resource allocation strategy with entry control can effectively improve the service experience of PRs. For example, when the arrival rate of PRs is equal to 0.5, under the parameter settings given by experiments, the proposed cloud resource allocation strategy can reduce the blocking rate of PRs by 47% and increase the throughput rate of PRs by 55% at most. Finally, we construct a revenue function to obtain the optimal entry thresholds and maximum revenues under different conditions. [ABSTRACT FROM AUTHOR]

The antagonistic Bacillus amyloliquefaciens HY2-1 was a marine microbiology that was isolated previously from the seabed silt of Beibu Gulf in China by dual culture with Penicillium digitatum. As a continuous study, the present work focused on evaluating the antimicrobial activity, identifying the produced active components, and revealing the fermentation characteristics of B. amyloliquefaciens HY2-1, respectively. It was found that B. amyloliquefaciens HY2-1 exhibited a broad-spectrum antimicrobial activity against the tested seven phytopathogenic fungi and five pathogenic bacteria by producing Bacillus lipopeptides such as fengycin A (C14 to C19 homologues) and surfactin (C14 and C15 homologues). Morphological observation of P. digitatum under light microscope, scanning electron microscopy, transmission electron microscopy, and fluorescence microscope inferred that B. amyloliquefaciens exerted the antagonistic activity by damaging the fungal cell membrane, thus inhibiting the mycelium growth and sporification of phytopathogenic fungi. As a marine microbiology, our results showed that B. amyloliquefaciens could survive and metabolize even at the culture condition with 110 g/L of NaCl concentration, and the produced antimicrobial compounds exhibited excellent thermostability and acid-alkali tolerance. The dynamic models were further constructed to theoretically analyze the fermentation process of B. amyloliquefaciens HY2-1, suggesting that the synthesis of antimicrobial compounds was coupled with both cell growth and cell biomass. In conclusion, the marine lipopeptides-producing B. amyloliquefaciens HY2-1 showed a promising prospect to be explored as a biocontrol agent for plant disease control of crops and postharvest preservation of fruits and vegetables, especially due to its outstanding stress resistance and the broad-spectrum and effective antagonist on various phytopathogenic fungi. [ABSTRACT FROM AUTHOR]

Air lasing is a simple and promising technique to efficiently produce coherent light in the atmosphere. Yet, its capability to obtain structured light like optical vortices or vector beams is still unexplored. Here, we demonstrate the generation of vortex superfluorescent radiation with the same orbital angular momentum as the pump beam, obtained via N2+ lasing by focusing a vortex pump beam on N2 gas. The vortex superfluorescence is amplified without altering the vorticity when seeded by a Gaussian beam, in which the vortex pump beam transfers the spatial spiral phase into the N2+ gain medium and the N2+ lasing obtains the phase information. The same mechanism is applied for a vector pump beam, turning the Gaussian seed into an amplified cylindrical vector beam. We corroborate our mechanism for generating vectorially structured light via air lasing with numerical calculations. This work provides a promising approach to generating structured light via superfluorescence. Air lasing is a cavity-free lasing action that is generated in air owing to the plasma filamentation process of high-power femtosecond laser pulses. The authors demonstrate that air lasing can be used to generate structured light, obtaining optical vortex beams and optical vector beams via superfluorescence from N2+. [ABSTRACT FROM AUTHOR]

Brain abscess is a rare but life-threatening complication of meningitis. The purpose of this study was to identify clinical features and potentially relevant factors of brain abscess in neonates with meningitis. This study was a propensity score–matched case–control study of neonates with brain abscess and meningitis in a tertiary pediatric hospital between January 2010 and December 2020. A total of 16 neonates with brain abscess were matched to 64 patients with meningitis. Demography, clinical characteristics, laboratory results, and pathogens were collected. Conditional logistic regression analyses were performed to identify the independent risk factors associated with brain abscess. The most common pathogen we found in the brain abscess group was Escherichia coli. Risk factors of brain abscess were identified: multidrug-resistant bacterial infection (OR, 11.204; 95% CI, 2.315–54.234; p = 0.003), C-reactive protein (CRP) > 50 mg/L (OR, 11.652; 95% CI, 1.799–75.470; p = 0.010). Conclusion: The risk factors of brain abscess are multidrug-resistant bacterial infection and CRP > 50 mg/L. Monitoring the level of CRP is essential. Bacteriological culture and rational use of antibiotics are necessary for the prevention of MDR bacterial infection as well as the occurrence of brain abscess. What is Known: • Morbidity and mortality of neonatal meningitis have declined, but brain abscess associated with neonatal meningitis is still life-threatening. What is New: • This study investigated relevant factors related to brain abscess. • It is important for neonatologists to perform prevention, early identification, and appropriate interventions for neonates with meningitis. [ABSTRACT FROM AUTHOR]

Nowadays, the accurate calculation and evaluation of processing carbon emissions (which refer to the total carbon emissions emitted by CNC consuming electrical energy during machining process) have become a hot topic owning to their great role on optimizing cutting processes, and thus reducing the global carbon dioxide emissions. However, the existing carbon emission calculation models for machining process do not pay much attention to the effect of tool wear on processing carbon emissions, which leads to the inaccurate evaluation. So in this paper, a practical carbon emission model for machining process is carried out. The model consists of two parts: (1) a relationship between processing carbon emissions and cutting power (which is the power only caused by removing materials from workpiece) and (2) a novel cutting power model considering tool wear condition. Afterwards, orthogonal experiments are performed on three different CNC machine tools in order to fit cutting power model’s constants and coefficients. Experiment results and related data analysis indicate that the presented cutting power model and the experimental evaluation method are accurate, and the flank wear length (VB), which is the index of evaluating tool wear condition, is necessary to be introduced as an independent variable. Compared with other models which do not consider the tool wear condition, this model succeeds to improve the calculation precision of processing carbon emissions, and provides more accurate data supporting the cutting parameter optimization. [ABSTRACT FROM AUTHOR]

Purpose: To examine the associations of healthy dietary patterns with cardiometabolic biomarkers and all-cause mortality among individuals with prediabetes. Methods: This cohort study included 8363 adults with prediabetes from the National Health and Nutrition Examination Survey 1999–2014. Healthy dietary patterns including Alternate Healthy Eating Index-2010 (AHEI-2010), Alternate Mediterranean Diet score (AMED), Dietary Approaches to Stop Hypertension score (DASH), and Healthy Eating Index-2015 (HEI-2015) were calculated based on 24-h dietary recall data. Mortality status was obtained by linkage to National Death Index records. Cardiometabolic biomarkers, including blood glucose, insulin, HbA1c, C-reactive protein (CRP), and lipids, were measured at recruitment. Results: During 61,991 person-years of follow-up, 991 deaths occurred. Comparing the extreme quartiles, the multivariable-adjusted hazard ratios (HRs) and 95% confidence intervals (CIs) for all-cause mortality were 0.65 (0.49, 0.85) for AHEI-2010 (P-trend = 0.002), 0.68 (0.50, 0.92) for AMED (P-trend = 0.004), 0.72 (0.53, 0.98) for DASH (P-trend = 0.03), and 0.78 (0.58, 1.05) for HEI-2015 (P-trend = 0.08). Besides, the HRs (95% CIs) for all-cause mortality per 20-percentile increment in scores were 0.78 (0.67, 0.90) for AHEI-2010 (P = 0.001), 0.73 (0.62, 0.86) for AMED (P < 0.001), 0.84 (0.69, 1.02) for DASH (P = 0.08), and 0.86 (0.74, 1.00) for HEI-2015 (P = 0.04). In addition, higher dietary scores were associated with favorable blood glucose, insulin, HOMA-IR, blood lipids, and CRP (all P-trend < 0.05). The high-density lipoprotein cholesterol and CRP explained 1.53–9.21% of the associations between dietary patterns and all-cause mortality (P < 0.05). Conclusions: Diets with higher AHEI-2010, AMED, DASH, and HEI-2015 were associated with improved cardiometabolic factors and lower all-cause mortality among individuals with prediabetes. These findings suggest that multiple healthy dietary patterns instead of a one-size-fits-all diet plan might be beneficial and acceptable for individuals with prediabetes. [ABSTRACT FROM AUTHOR]

As a new food raw material, Acer truncatum seed has been used in the production of edible oil. However, the research on the processing residue (seed meal) has not been reported. The Acer truncatum seed meal was hydrolyzed by seven enzymes and the enzymic polypeptides obtained were characterized by thermogravimetric analysis, gel permeation chromatography, fourier transform infrared spectroscopy and zeta pals dynamic light scattering. In addition, the degree of hydrolysis, amino acid composition, antioxidant activity, α-glucosidase inhibition activity and α-amylase inhibition activity of enzymatic polypeptide were evaluated. The results showed that the yields, average molecular weights, average particle sizes and zeta potentials of enzymic polypeptides obtained were 20.5–40.2%, 7.8–13.9 kDa, 288.3–997.5 nm and (−)1.8 to (−)36.4 mV, respectively. The bioactivity results showed that the enzymatic polypeptides not only had higher antioxidant activity, but also better α-glucosidase and α-amylase inhibition activities than the raw materials. Among the seven enzymatic polypeptides, the alkaline protease enzymatic polypeptide had the highest content of the eight essential amino acids (20.3%), the largest value of hydrolysis degree (15.4%) and the most significant bioactivity. The study will provide the data support for developing the new application of seed meal from Acer truncatum. [ABSTRACT FROM AUTHOR]

Casing steel is prone to reduced mechanical properties and occurred environmentally assisted cracking finally in sour well environment containing H2S and CO2. The paper mainly researched on the relationship between mechanical properties and hydrogen permeation, exposed casing steel P110 to air, NACE A solution, and simulated formation water containing H2S and CO2 with a stress of 80% yield strength at 60 °C for 168 h, testing its mechanical properties shown strain-aging phenomenon and ductile–brittle transition. The lowest mechanical properties are occurred in the sour well environment, its yield strength, and tensile strength, respectively, reduction 5.0% and 4.7%, while a loss of 41.4% in fracture toughness. With temperature increased from 25 to 60 °C, the hydrogen diffusion coefficient increases by 1.59 times, and there is a mutation in mechanical properties of P110, when the hydrogen diffusion coefficient is 1.64 × 10–4 cm2/s and the subsurface hydrogen concentration is.1.653 × 10–5%. The steel P110 has shown a ductile fracture with toughnest exposed in the air and shown cleavage fracture characteristics exposed to sour environments, indicating that hydrogen permeation has changed the fracture mode from ductile to brittle. This method can be used to test and compute the strength attenuation effect of casing P110 serviced in sour well environments. [ABSTRACT FROM AUTHOR]

spt23 plays multiple roles in the thermal tolerance of budding yeast. spt23 regulates unsaturated lipid acid (ULA) content in the cell, which can then significantly affect cellular thermal tolerance. Being a Ty suppressor, spt23 can also interact with transposons (Tys) that are contributors to yeast's adaptive evolution. Nevertheless, few studies have investigated whether and how much spt23 can exert its regulatory functions through transposons. In this study, expression quantitative trait loci (eQTL) analysis was conducted with thermal-tolerant Saccharomyces cerevisiae strains, and spt23 was identified as one of the most important genes in mutants. spt23-overexpression (OE), deletion (Del), and integrative-expressed (IE) strains were constructed. Their heat tolerance, ethanol production, the expression level of key genes, and lipid acid contents in the cell membranes were measured. Furthermore, LTR (long terminal repeat)-amplicon sequencing was used to profile yeast transposon activities in the treatments. The results showed the Del type had a higher survival rate, biomass, and ethanol production, revealing negative correlations between spt23 expression levels and thermal tolerance. Total unsaturated lipid acid (TULA) contents in cell membranes were lower in the Del type, indicating its negative association with spt23 expression levels. The Del type resulted in the lower richness and higher evenness in LTR distributions, as well as higher transposon activities. The intersection of 3 gene sets and regression analysis revealed the relative weight of spt23's direct and TY-induced influence is about 4:3. These results suggested a heat tolerance model in which spt23 increases cell thermal tolerance through transcriptional regulation in addition to spt23-transposon triggered unknown responses. Key points: • spt23 is a key gene for heat tolerance, important for LA contents but not vital. • Deletion of spt23 decreases in yeast's LTR richness but not in evenness. • The relative weight of spt23's direct and TY-induced influence is about 4:3. [ABSTRACT FROM AUTHOR]

The simulation of wave propagation in high-temperature media requires thermoelastic theory. In this paper, we apply the rotated-staggered-grid pseudo-spectral method (RSG-PSM) to solving thermoelastic governing equations based on L-S theory. A time splitting method is used to solve the stiffness problem of the equations, and we introduce the rotated staggered pseudo-spectral operator and centered pseudo-spectral operator to compute the first-order spatial derivatives and second-order spatial derivatives, respectively. In the case of the heterogeneous-medium model, the Crank-Nicolson explicit method is used instead of the pseudo-spectral method to compute the wavefield. The properties and propagation of the thermal coupled wavefield are discussed, and we compare the simulation results obtained using the pseudo-spectral method, staggered-grid pseudo-spectral method, and RSG-PSM. In the case of an isotropic homogeneous medium, we obtain stable and highly accurate results using the time splitting method combined with the RSG-PSM. However, the algorithm cannot be applied with a large time step when the thermal conductivity changes dramatically, and the algorithm is unstable when the reference temperature has a gradient distribution. The optimal combined application of the mesh generation mode and numerical algorithm is explored, laying a foundation for the extension of these methods to thermoporoelasticity, thermoviscoelasticity, and anisotropy. [ABSTRACT FROM AUTHOR]

A novel one-dimensional coordination polymer, named as {[Cd(ipa)(Hpzp)(H2O)]·2H2O}n (Cd-CP), (where ipa = isophthalic acid, Hpzp = 4-(1 H-Pyrazol-4-yl)pyridine), have been successfully synthesized by facile hydrothermal method. Single crystal X-ray diffraction (SC-XRD) demonstrate that the complex Cd-CP was crystallized in the P-1 space group of the triclinic crystal system. In addition, solid-state fluorescence spectroscopy showed that the complex Cd-CP has excellent luminescent properties. Further studies showed that complex Cd-CP could be used for the highly sensitive detection of chloroform, tetracycline hydrochloride (TCH) and oxytetracycline (OTC), with detection limit (LOD) of 0.21 µM for TCH and 0.14 µM for OTC, respectively. Finally, a rational fluorescence sensing mechanism was also scrutinized and proposed. [ABSTRACT FROM AUTHOR]

The laminin-binding glycan (matriglycan) on α-dystroglycan (α-DG) enables diverse roles, from neuronal development to muscle integrity. Reduction or loss of matriglycan has also been implicated in cancer development and metastasis, and specifically associated with high-grade tumors and poor prognoses in breast cancers. Hyperglycosylation of α-DG with LARGE overexpression is shown to inhibit cancer cell growth and tumorigenicity. We recently demonstrated that ribitol, considered to be a metabolic end-product, enhances matriglycan expression in dystrophic muscles in vivo. In the current study, we tested the hypothesis that ribitol could also enhance matriglycan expression in cancer cells. Our results showed for the first time that ribitol is able to significantly enhance the expression of matriglycan on α-DG in breast cancer cells. The ribitol effect is associated with an increase in levels of CDP-ribitol, the substrate for the ribitol-5-phosphate transferases FKRP and FKTN. Direct use of CDP-ribitol is also effective for matriglycan expression. Ribitol treatment does not alter the expression of FKRP, FKTN as well as LARGEs and ISPD which are critical for the synthesis of matriglycan. The results suggest that alteration in substrates could also be involved in regulation of matriglycan expression. Interestingly, expression of matriglycan is related to cell cycle progression with highest levels in S and G2 phases and ribitol treatment does not alter the pattern. Although matriglycan up-regulation does not affect cell cycle progression and proliferation of the cancer cells tested, the novel substrate-mediated treatment opens a new approach easily applicable to experimental systems in vivo for further exploitation of matriglycan expression in cancer progression and for therapeutic potential. [ABSTRACT FROM AUTHOR]

Sex ratio is a fundamental concept in evolutional biology, and theory predicts that parents should invest in sons and daughters according to the fitness returns they expect from them. The fitness returns may depend on the timing of breeding and on parental conditions leading to sex ratios that depend on breeding date and/or parental quality. Here, we investigate the offspring sex ratio in a small shorebird, the Kentish Plover Charadrius alexandrinus, in a large breeding population in Eastern China, and test whether the parents adjust their offspring's sex in response to hatch date, brood age and their own body condition. Using 1264 chicks from 676 broods that were molecularly sexed, we show that hatchling sex ratio was not significantly different from unity. Hatchling sex ratios were not related to hatch date or to the body condition of parents. In addition, we sexed 138 eggs that were confiscated from illegal egg collectors and found that the mortality of female and male embryos was not significantly different. The latter result is important by suggesting that neither primary sex ratio (i.e., at conception) nor secondary sex ratio (i.e., at hatching) is biased. Taken together, the even offspring sex ratio in Chinese Kentish Plovers is consistent with recent analyses of six plover populations that found even sex ratios at hatching. Future works should investigate whether the even sex ratio persists into adulthood, or it may shift toward more males (or females) due to sex-biased mortalities of juveniles and/or adults. [ABSTRACT FROM AUTHOR]

Key message: We found that ApGGPPS1, ApGGPPS2, and ApGGPPS3 can convert IPP and DMAPP to GGPP. ApGGPPS2 is probably involved in andrographolide biosynthesis. ApGGPPS3 may be responsible for the synthesis of the cytosolic GGPP.Abstract: Andrographis paniculata is a traditional herb for the treatment of sore throat, flu, upper respiratory tract infections and other disorders. In A. paniculata, GGPP is not only the precursor of andrographolide and its primary bioactive compounds, but also the precursor of chlorophylls, carotenoids, gibberellins, and abscisic acid, which are the biomolecules of photosynthesis, growth regulation and other physiological and ecological processes. In this study, four cDNAs (named ApGGPPS1, ApGGPPS2, ApGGPPS3 and ApGGPPS4) encoding geranylgeranyl pyrophosphate synthases from A. paniculata were putatively isolated. Bioinformatic and phylogenetic analyses suggested that these ApGGPPS are highly similar to the geranylgeranyl pyrophosphate synthases in other plants. Prokaryotic expression showed that ApGGPPS1, ApGGPPS2 and ApGGPPS3 could convert IPP and DMAPP to GGPP, although ApGGPPS4 lacks a similar function. The expression of ApGGPPS2 was similar as ApCPS2 under MeJA treatment, ApCPS2 involved in the biosynthesis pathway of andrographolide (Shen et al., Biotechnol Lett 38:131-137, 2016a), has been proven through Virus-induced Gene Siliencing (VIGS) (Shen et al., Acta Bot Boreal 36:17-22, 2016b), and the subcellular localization of ApGGPPS2 was shown to localize in the plastid, suggested that ApGGPPS2 could be the key synthase in the biosynthesis pathway of andrographolide. In addition, ApGGPPS3 was shown to localize in the cytoplasm, suggested that ApGGPPS3 may be responsible for the synthesis of cytosolic GGPP, which may participate in the synthesis of cytosolic oligoprenols as side chains to produce ubiquinone, dolichols or other isoprenoids, in the synthesis of polyisoprenoids, and in protein prenylation. [ABSTRACT FROM AUTHOR]

Process route planning bridges the gap between design stage and manufacturing stage, which transforms workblanks into parts or products. The decisions of processing methods, machines, cutting tools, and sequence of process stages during process route planning have a significant impact on carbon emissions in manufacturing process. To reduce carbon emissions of process routes of parts and simultaneously consider economic and high-efficiency factors, a low-carbon multi-objective process route optimization method is proposed. Firstly, a constructed PBOM (process bill of material) based on machining features of parts is used to quantify carbon emissions of every processing step. Secondly, a multi-objective optimization model of process routes with the objectives of minimum carbon emissions, minimum processing cost, and minimum processing time is built based on the PBOM. Thirdly, a multi-objective ant colony algorithm is designed to solve the proposed model. Finally, a practical applicable bearing seat is taken as a case study to verify the rationality of the proposed method. Comparison results show that the proposed method can obtain the low-carbon, economic, and high-efficiency process routes for parts. [ABSTRACT FROM AUTHOR]

A major challenge of profiling chlorogenic acids (CGA) in natural products is to effectively detect unknown or minor isomeric compounds. Here, we developed an effective strategy, typical ultraviolet (UV) spectra in combination with diagnostic mass fragmentation analysis based on HPLC-DAD-QTOF-MS/MS, to comprehensively profile CGA in the buds of Lonicera macranthoides. First, three CGA UV patterns were obtained by UV spectra screening. Second, 13 types of CGA classified by molecular weights were found by thorough analysis of CGA peaks using high-resolution MS. Third, selected ion monitoring (SIM) was carried out for each type of CGA to avoid overlooking of minor ones. Fourth, MS/MS spectra of each CGA were investigated. Then 70 CGA were identified by matching their UV spectra, accurate mass signals and fragmentation patterns with standards or previously reported compounds, including six caffeoylquinic acids (CQA), six diCQA, one triCQA, three caffeoylshikimic acids (CSA), six diCSA, one triCSA, three p-coumaroylquinic acids ( pCoQA), four p-coumaroylcaffeoylquinic acids ( pCoCQA), four feruloylquinic acids (FQA), five methyl caffeoylquinates (MCQ), three ethyl caffeoylquinates (ECQ), three dimethoxycinnamoylquinic acids (DQA), six caffeoylferuloylquinic acids (CFQA), six methyl dicaffeoylquinates (MdiCQ), four FQA glycosides (FQAG), six MCQ glycosides (MCQG), and three ethyl dicaffeoylquinates (EdiCQ). Forty-five of them were discovered from Lonicera species for the first time, and it is noted that CGA profiles were investigated for the first time in L. macranthoides. Results indicated that the developed method was a useful approach to explore unknown and minor isomeric compounds from complex natural products. [Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]

The possible exhaustion of fossil fuels in the near future and soaring global energy demand have driven the search for new types of sustainable and renewable alternatives. Perovskite (CHNHPbX, X = I, Br, Cl) solar cells are a type of solar cell based on a perovskite absorber, most commonly a tin halide-based or hybrid organic-inorganic lead material, as the visible-light sensitizer layer, which produces electricity from sunlight. Recently, perovskite solar cells have received substantial worldwide attention. Compared with traditional solar cells, the perovskite solar cells can obtain high efficiency with a simple architecture and via a cost-effective process. In the latest 5 years, the efficiency of perovskite solar cells to convert power has skyrocketed from 3.8 % to more than 19.3 %. It is the fastest advancing solar technology to date. The highest efficiency demonstrated by perovskite solar cells is higher than that of dye-sensitized solar cells (DSSCs). A lager number of research groups have demonstrated that perovskite solar cells may ultimately boost efficiency as high as 25 %. The high efficiency and cheap production costs make it evident that perovskite solar cells have great potential to be commercialized soon. In this review, the history, materials, processing and architecture of solar cells are discussed to obtain a better understanding of high-performance perovskite solar cells. [ABSTRACT FROM AUTHOR]

Key message: We found triptolide synthesis is correlated with the expressions of TwGGPPS1 and TwGGPPS4 . This lays the foundation for future studies of biosynthetic pathways for triptolide and other diterpenoids in T. wilfordii. Abstract: Tripterygium wilfordii is a traditional Chinese medical plant commonly used to treat rheumatoid arthritis. One of its main bioactive compounds is triptolide, which is identified as an abietane-type diterpenoid natural product. Geranylgeranyl diphosphate synthase (GGPPS) catalyses the synthesis of GGPP (geranylgeranyl diphosphate), the common precursor of diterpenes, and is therefore a crucial enzyme in diterpene biosynthesis. A previous study showed that GGPP could be catalyzed by copalyl diphosphate synthase and kaurene synthase like of Salvia miltiorrhiza (SmCPS, SmKSL) to miltiradiene, a key intermediate in tanshinone biosynthesis. In this paper, five new full-length cDNAs ( TwGGPPS) encoding GGPP synthases were cloned from T. wilfordii. Sequence comparisons revealed that all six TwGGPPSs (including TwGGPPS2 cloned previously) exhibit similarities to GGPPSs of other plants. Subsequent functional complement assays demonstrated that TwGGPPS1, TwGGPPS4 and TwGGPPS5 can participate in miltiradiene biosynthesis in the recombinant E. coli. Correlation analysis of gene expressions and secondary metabolite accumulation indicated that TwGGPPS1 and TwGGPPS4 are likely involved in the biosynthesis of triptolide. These findings lay the foundation for future studies of the biosynthetic pathways for triptolide and other diterpenoids in T. wilfordii. [ABSTRACT FROM AUTHOR]

The travel time and amplitude of ground-penetrating radar (GPR) waves are closely related to medium parameters such as water content, porosity, and dielectric permittivity. However, conventional estimation methods, which are mostly based on wave velocity, are not suitable for real complex media because of limited resolution. Impedance inversion uses the reflection coefficient of radar waves to directly calculate GPR impedance and other parameters of subsurface media. We construct a 3D multiscale stochastic medium model and use the mixed Gaussian and exponential autocorrelation function to describe the distribution of parameters in real subsurface media. We introduce an elliptical Gaussian function to describe local random anomalies. The tapering function is also introduced to reduce calculation errors caused by the numerical simulation of discrete grids. We derive the impedance inversion workflow and test the calculation precision in complex media. Finally, we use impedance inversion to process GPR field data in a polluted site in Mongolia. The inversion results were constrained using borehole data and validated by resistivity data. [ABSTRACT FROM AUTHOR]

Ag nanoparticles self-supported on AgVO nanobelts (Ag/AgVO NBs) are synthesized using a sonochemical-hydrothermal method. Ag/AgVO NBs are studied by characterization of powder X-ray diffraction, N adsorption, transmission electron microscopy, H temperature-programmed reduction, and X-ray photoelectron spectroscopy. The catalytic performances of the as-prepared materials were carefully investigated in gas phase selective oxidation of toluene. Higher catalytic activity and better selectivity to benzaldehyde and benzoic acid are achieved by this belt-like Ag/AgVO nanocomposite in gas phase oxidation of toluene in comparison with those of bulk VO and Ag supported on VO nanobelts (Ag/VO NBs). The superior catalytic performance of Ag/AgVO NBs was attributed to its unique redox property as well as the synergistic effect between Ag nanoparticles and AgVO. [ABSTRACT FROM AUTHOR]

A key problem in seismic inversion is the identification of the reservoir fluids. Elastic parameters, such as seismic wave velocity and formation density, do not have sufficient sensitivity, thus, the conventional amplitude-versus-offset (AVO) method is not applicable. The frequency-dependent AVO method considers the dependency of the seismic amplitude to frequency and uses this dependency to obtain information regarding the fluids in the reservoir fractures. We propose an improved Bayesian inversion method based on the parameterization of the Chapman model. The proposed method is based on 1) inelastic attribute inversion by the FDAVO method and 2) Bayesian statistics for fluid identification. First, we invert the inelastic fracture parameters by formulating an error function, which is used to match observations and model data. Second, we identify fluid types by using a Markov random field a priori model considering data from various sources, such as prestack inversion and well logs. We consider the inelastic parameters to take advantage of the viscosity differences among the different fluids possible. Finally, we use the maximum posteriori probability for obtaining the best lithology/fluid identification results. [ABSTRACT FROM AUTHOR]

Muscular dystrophy-dystroglycanopathies comprise a heterogeneous and complex group of disorders caused by loss-of-function mutations in a multitude of genes that disrupt the glycobiology of α-dystroglycan, thereby affecting its ability to function as a receptor for extracellular matrix proteins. Of the various genes involved, FKRP codes for a protein that plays a critical role in the maturation of a novel glycan found only on α-dystroglycan. Yet despite knowing the genetic cause of FKRP-related dystroglycanopathies, the molecular pathogenesis of disease and metabolic response to therapeutic intervention has not been fully elucidated. To address these challenges, we utilized mass spectrometry-based metabolomics to generate comprehensive metabolite profiles of skeletal muscle across diseased, treated, and normal states. Notably, FKRP-deficient mice elicit diverse metabolic abnormalities in biomarkers of extracellular matrix remodeling and/or aging, pentoses/pentitols, glycolytic intermediates, and lipid metabolism. More importantly, the restoration of FKRP protein activity following AAV-mediated gene therapy induced a substantial correction of these metabolic impairments. While interconnections of the affected molecular mechanisms remain unclear, our datasets support the notion that global metabolic profiling can be valuable for determining the involvement of previously unsuspected regulatory or pathological pathways as well as identifying potential targets for drug discovery and diagnostics. [ABSTRACT FROM AUTHOR]