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A dual-emission ratio-fluorescent sensing nanohybrid based on Radix Hedysari green-synthesized carbon quantum dots (CDs) and glutathione-functionalized gold nanoclusters (GSH-AuNCs) had been developed for the determination of cefodizime sodium (CDZM). The designed fluorescence nanohybrid had two significant fluorescence emission peaks at 458 nm and 569 nm when excited at 360 nm, which was attributed to the CDs and GSH-AuNCs. With the addition of CDZM, the fluorescence at 458 nm was slightly weakened while the fluorescence at 569 nm was enhanced obviously. Based on the relationship between the I569/I458 fluorescence intensity ratio and the concentration of CDZM, the designed nanohybrid exhibited a good linearity range of 1.0–1000.0 μM and the limit of detection (LOD) was 0.19 μM. The method was finally applied in the detection of CDZM in urine, showing the potential applications in complicated biological samples. [ABSTRACT FROM AUTHOR]

MOF-74 or M2(dhtp) (M = metal ions, dhtp = 2,5-dihydroxyterephthalic acid), as a typical class of metal–organic frameworks (MOF), have garnered considerable interest due to their abundant unsaturated metal sites. However, environmental and economic limitations caused by the extensive use of organic solvents in traditional syntheses hinder their industrial applications. Although water as a green solvent is considered to be the best candidate solvent, water-based MOFs often have poor crystallinity and long synthesis time, and controlling the particle size is difficult. Herein, a water-based strategy is proposed to synthesize high-quality MOF-74–Co with controllable particle sizes in a rotating packed bed (RPB) reactor using high-gravity technology. MOF-74–Co could be rapidly prepared in the RPB, and shows a smaller and more uniform particle size, higher crystallinity, and larger specific surface area, as compared to the counterpart prepared in a traditional stirred tank reactor. Further adopting acetic acid as a modulator, the as-prepared MOF-74–Co has the highest BET surface area (1599 m2 g−1) in the reported literature so far and simultaneously possesses a high space–time yield (293 kg m−3 day−1). High-quality MOF-74–Zn and MOF-74–Ni can also be prepared, proving the generality of this strategy. Furthermore, the small-sized MOF-74–Co-78 nm exhibits a faster adsorption rate and a larger saturation adsorption capacity (298 mg g−1) for CO2 compared with large-sized samples. This study not only advances the field of green synthesis of MOFs but also paves the way for efficient manufacturing processes in MOF-74 synthesis for CO2 adsorption. [ABSTRACT FROM AUTHOR]

The goal of our study was to evaluate the potential role of sTNF-RI as a biomarker of renal involvement in SLE patients and active SLE. The study sample consisted of two cohorts. The discovery cohort included 16 SLE patients without renal involvement (non-LN), 60 lupus nephritis (LN) patients and 21 healthy controls (HCs) and the replication cohort included 18 SLE non-LN patients, 116 LN patients and 36 HCs. The sTNF-RI levels differed significantly in the discovery cohort. The plasma sTNF-RI levels were higher in LN patients than in non-LN patients (p =.009) and HCs (p = 4 × 10−6). Plasma sTNF-RI levels were significantly higher in non-LN patients than in HCs (p =.03). The finding was confirmed in independent replication cohort (LNs vs. non-LN, p = 4.053 × 10−7; LNs vs. HCs, p = 2.395 × 10−18; non-LN vs. HCs, p = 2.51 × 10−4). The plasma sTNF-RI levels were associated with disease activity, renal function in SLE patients and urine protein in LN patients. The multivariate analysis revealed that high sTNF-RI was an independent risk factor for renal involvement. The multivariate logistic regression results suggested that high TNF-RI, high systolic blood pressure, high serum creatinine, low C4 and positive anti-dsDNA were independent risks of active SLE patients. A nomogram was constructed based on the results of multivariate logistic regression analysis and it was practical in predicting the risk of the active SLE patients. Immunohistochemistry suggested that the expression of TNF-RI in the kidney was increased. Plasma sTNF-RI might be a good biomarker of renal involvement and disease activity in SLE patients. [ABSTRACT FROM AUTHOR]

Background: The primary aim of the present study was to explore risk factors for portal vein system thrombosis following splenectomy. Methods: A systematic search of PubMed, Embase and Cochrane libraries was conducted to identify original studies that fulfilled the inclusion criteria. Raw data on potential risk factors for portal vein system thrombosis after splenectomy were extracted for meta‐analysis. Subsequently, a sensitivity analysis was conducted to verify the stability of the results. Results: Eighteen studies with 626 thrombosis events from 1807 splenectomy met the inclusion criteria. Larger spleen volume (SMD 0.44, P = 0.000), broader splenic vein diameter (WMD 2.30, P = 0.000), broader portal vein diameter (WMD 2.08, P = 0.000), a lower velocity of portal blood flow (WMD −0.91, P = 0.001), decreased platelet count (WMD −5.14, P = 0.007), decreased white blood cell (WMD −0.40, P = 0.027), decreased haemoglobin (WMD −9.14, P = 0.002), ascites (OR 1.81, P = 0.003) and bleeding history before surgery (OR 1.88, P = 0.002) were identified to be factors that exacerbated the risk of portal vein system thrombosis after splenectomy. Sex, age, preoperative prothrombin time, postoperative platelet count, postoperative D‐dimer, operation time and intraoperative blood loss, did not increase the risk of thrombosis. Conclusion: Larger spleen volume, broader splenic vein diameter, broader portal vein diameter, a lower velocity of portal blood flow, ascites, bleeding history before surgery, decreased platelet count, white blood cell and haemoglobin may increase the risk of portal vein system thrombosis. [ABSTRACT FROM AUTHOR]

Enantioconvergent catalysis enables the conversion of racemic molecules into a single enantiomer in perfect yield and is considered an ideal approach for asymmetric synthesis. Despite remarkable advances in this field, enantioconvergent transformations of inert tertiary C−H bonds remain largely unexplored due to the high bond dissociation energy and the surrounding steric repulsion that pose unparalleled constraints on bond cleavage and formation. Here, we report an enantioconvergent Pd‐catalyzed alkylation of racemic tertiary allylic C−H bonds of α‐alkenes, providing a unique approach to access a broad range of enantioenriched γ,δ‐unsaturated carbonyl compounds featuring quaternary carbon stereocenters. Mechanistic studies reveal that a stereoablative event occurs through the rate‐limiting cleavage of tertiary allylic C−H bonds to generate σ‐allyl‐Pd species, and the achieved E/Z‐selectivity of σ‐allyl‐Pd species effectively regulates the diastereoselectivity via a nucleophile coordination‐enabled SN2′‐allylation pathway. [ABSTRACT FROM AUTHOR]

Enantioconvergent catalysis enables the conversion of racemic molecules into a single enantiomer in perfect yield and is considered an ideal approach for asymmetric synthesis. Despite remarkable advances in this field, enantioconvergent transformations of inert tertiary C−H bonds remain largely unexplored due to the high bond dissociation energy and the surrounding steric repulsion that pose unparalleled constraints on bond cleavage and formation. Here, we report an enantioconvergent Pd‐catalyzed alkylation of racemic tertiary allylic C−H bonds of α‐alkenes, providing a unique approach to access a broad range of enantioenriched γ,δ‐unsaturated carbonyl compounds featuring quaternary carbon stereocenters. Mechanistic studies reveal that a stereoablative event occurs through the rate‐limiting cleavage of tertiary allylic C−H bonds to generate σ‐allyl‐Pd species, and the achieved E/Z‐selectivity of σ‐allyl‐Pd species effectively regulates the diastereoselectivity via a nucleophile coordination‐enabled SN2′‐allylation pathway. [ABSTRACT FROM AUTHOR]

The prevalence of cadmium (Cd)‐polluted agricultural soils is increasing globally, and arbuscular mycorrhizal fungi (AMF) can reduce the absorption of heavy metals by plants and improve mineral nutrition. However, the immobilization of the rhizosphere on cadmium is often overlooked. In this study, Glomus mosseae and Medicago sativa were established as symbiotes, and Cd migration and environmental properties in the rhizosphere were analyzed. AMF reduced Cd migration, and Cd2+ changed to an organic‐bound state. AMF symbiosis treatment and Cd exposure resulted in microbial community variation, exhibiting a distinct deterministic process (|βNTI| > 2), which ultimately resulted in a core microbiome function of heavy metal resistance and nutrient cycling. AMF increased available N and P, extracellular enzyme activity (LaC, LiP, and CAT), organic matter content (TOC, EOC, and GRSP), and Eh of the rhizosphere soil, significantly correlating with decreased Cd migration (p < 0.05). Furthermore, AMF significantly affected root metabolism by upregulating 739 metabolites, with flavonoids being the main factor causing microbiome variation. The structural equation model and variance partial analysis revealed that the superposition of the root metabolites, microbial, and soil exhibited the maximum explanation rate for Cd migration reduction (42.4%), and the microbial model had the highest single explanation rate (15.5%). Thus, the AMF in the rhizosphere microenvironment can regulate metabolite–soil–microbial interactions, reducing Cd migration. In summary, the study provides a new scientific explanation for how AMF improves plant Cd tolerance and offers a sustainable solution that could benefit both the environment and human health. Highlights: Arbuscular mycorrhizal fungi (AMF) resulted in microbial community assembling to migration capacity.AMF promotes recruitment of metal‐resistant microbial community.AMF changes root metabolites to affect rhizosphere bacterial community assembly.AMF passivates rhizosphere Cd based on regulating ecological characteristics. [ABSTRACT FROM AUTHOR]

Molecular crystals with the ability to transform light energy into macroscopic mechanical motions are a promising class of materials with potential applications in actuating and photonic devices. In regard to such materials, coordination polymers that exhibit dynamic photomechanical motion, associated with a phase transition, are unknown. Herein, we report an intriguing photoactive, one‐dimensional ZnII coordination polymer, 1, derived from 1,3,5‐tri‐4‐pyridyl‐1,2‐ethenylbenzene and 3,5‐difluorobenzoate. Single crystals of 1 under UV light irradiation exhibit rapid shrinking and bending, violent bursting‐jumping, splitting, and cracking behavior. Single‐crystal X‐ray diffraction analysis and 1H NMR spectroscopy reveal an unusual photoinduced phase transition involving a single‐crystal‐to‐single‐crystal [2+2] cycloaddition reaction that results in photomechanical responses. Interestingly, crystals of 1, which are triclinic with space group P1‾ ${P\bar{1}}$ , are transformed into a higher symmetry, monoclinic cell with space group C2/c. This process represents a rare example of symmetry enhancement upon photoirradiation. The photomechanical activity is likely due to the sudden release of stress associated with strained molecular geometries and significant solid‐state molecular movement arising from cleavage and formation of chemical bonds. A composite membrane fabricated from 1 and polyvinyl alcohol (PVA) also displays interesting photomechanical behavior under UV light illumination, indicating the material's potential as a photoactuator. [ABSTRACT FROM AUTHOR]

Molecular crystals with the ability to transform light energy into macroscopic mechanical motions are a promising class of materials with potential applications in actuating and photonic devices. In regard to such materials, coordination polymers that exhibit dynamic photomechanical motion, associated with a phase transition, are unknown. Herein, we report an intriguing photoactive, one‐dimensional ZnII coordination polymer, 1, derived from 1,3,5‐tri‐4‐pyridyl‐1,2‐ethenylbenzene and 3,5‐difluorobenzoate. Single crystals of 1 under UV light irradiation exhibit rapid shrinking and bending, violent bursting‐jumping, splitting, and cracking behavior. Single‐crystal X‐ray diffraction analysis and 1H NMR spectroscopy reveal an unusual photoinduced phase transition involving a single‐crystal‐to‐single‐crystal [2+2] cycloaddition reaction that results in photomechanical responses. Interestingly, crystals of 1, which are triclinic with space group P1‾ ${P\bar{1}}$ , are transformed into a higher symmetry, monoclinic cell with space group C2/c. This process represents a rare example of symmetry enhancement upon photoirradiation. The photomechanical activity is likely due to the sudden release of stress associated with strained molecular geometries and significant solid‐state molecular movement arising from cleavage and formation of chemical bonds. A composite membrane fabricated from 1 and polyvinyl alcohol (PVA) also displays interesting photomechanical behavior under UV light illumination, indicating the material's potential as a photoactuator. [ABSTRACT FROM AUTHOR]

ORR activity and selectivity on native oxide film-covered Ti were quantitatively studied by the reactive tip generation/substrate collection (RTG/SC) mode of scanning electrochemical microscopy (SECM) and further clarified by theoretical calculations. The ORR behavior on Ti is highly film characteristics-dependent. [Display omitted] • ORR activity and selectivity on spontaneous film-covered Ti were studied. • Effects of key factors were quantified by SECM and further clarified by theoretical calculations. • ORR is sensitive to film features, especially on the highly reduced Ti surface. • Hydrogen bonds and/or electrostatic effect improve 4e– selectivity while Cl– suppress reactivity. • This work provides theoretical support and possible guidance for ORR on oxide-covered metals. Unlike noble metals, the oxygen reduction reaction (ORR) behavior on Ti is more complicated due to its spontaneously formed oxide film. This film results in sluggish ORR kinetics and tends to be reduced within ORR potential region, causing the weak and multi-reaction coupled current. Though Ti is being used in chemical and biological fields, its ORR research is still underexplored. We innovatively employed the modified reactive tip generation-substrate collection (RTG/SC) mode of scanning electrochemical microscopy (SECM) with high efficiency of 97.2 % to quantitatively study the effects of film characteristics, solution environment (pH, anion, dissolved oxygen), and applied potential on the ORR activity and selectivity of Ti. Then, density functional theory (DFT) and molecular dynamics (MD) analyses were employed to elucidate its ORR behavior. On highly reduced Ti, film properties dominate ORR behavior with promoted 4e– selectivity. Rapid film regeneration in alkaline/O 2 -saturated conditions inhibits ORR activity. Besides, ORR is sensitive to anion species in neutral solutions while showing enhanced 4e– reduction in alkaline media. All the improved 4e– selectivities originate from the hydrogen bond/electrostatic stabilization effect, while the decayed ORR activity by Cl– arises from the suppressed O 2 adsorption. This work provides theoretical support and possible guidance for ORR research on oxide-covered metals. [ABSTRACT FROM AUTHOR]

Social network analysis has created a productive framework for the analysis of the histories of patient-physician interactions and physician collaboration. Notable is the construction of networks based on the data of “referral paths” – sequences of patient-specific temporally linked physician visits – in this case, culled from a large set of Medicare claims data in the United States. Network constructions depend on a range of choices regarding the underlying data. In this paper we introduce the use of a five-factor experiment that produces 80 distinct projections of the bipartite patient-physician mixing matrix to a unipartite physician network derived from the referral path data, which is further analyzed at the level of the 2,219 hospitals in the final analytic sample. We summarize the networks of physicians within a given hospital using a range of directed and undirected network features (quantities that summarize structural properties of the network such as its size, density, and reciprocity). The different projections and their underlying factors are evaluated in terms of the heterogeneity of the network features across the hospitals. We also evaluate the projections relative to their ability to improve the predictive accuracy of a model estimating a hospital’s adoption of implantable cardiac defibrillators, a novel cardiac intervention. Because it optimizes the knowledge learned about the overall and interactive effects of the factors, we anticipate that the factorial design setting for network analysis may be useful more generally as a methodological advance in network analysis. [ABSTRACT FROM AUTHOR]

Gastric cancer is one of the most common malignant tumors in the world. Its incidence ranks fifth among all malignant tumors worldwide and is the third leading cause of death among cancer patients. Surgery is currently considered to be the only radical treatment. However, the low rate of early diagnosis means that most patients have an advanced-stage disease at diagnosis which lost the chance of surgery. Therefore, the main treatment for advanced gastric cancer includes chemotherapy, targeted therapy, immunotherapy. The purpose of this study is to review the transition and current patterns of drug therapy for advanced gastric cancer and to provide assistance for subsequent clinical studies in advanced gastric cancer. [ABSTRACT FROM AUTHOR]

Urological chronic pelvic pain syndrome (UCPPS) manifests as pelvic pain with frequent urination and has a 10% prevalence rate without effective therapy. Nanoceria (cerium oxide nanoparticles [CNPs]) were synthesized in this study to achieve potential long-term pain relief, using a commonly used UCPPS mouse model with cyclophosphamide-induced cystitis. Transcriptome sequencing analysis revealed that serpin family B member 2 (SerpinB2) was the most upregulated marker in mouse bladder, and SerpinB2 was downregulated with CNP pretreatment. The transcriptome sequencing analysis results agreed with quantitative polymerase chain reaction and western blot analysis results for the expression of related mRNAs and proteins. Analysis of Gene Expression Omnibus (GEO) datasets revealed that SerpinB2 was a differentially upregulated gene in human UCPPS. In vitro SerpinB2 knockdown downregulated proinflammatory chemokine expression (chemokine receptor CXCR3 and C-X-C motif chemokine ligand 10) upon treatment with 4-hydroperoxycyclophosphamide. In conclusion, CNP pretreatment may prevent the development of UCPPS, and reactive oxygen species (ROS) scavenging and SerpinB2 downregulation may modulate the immune response in UCPPS. [ABSTRACT FROM AUTHOR]

Solar flares are a kind of violent solar eruptive activity phenomenon and an important warning device of space weather disturbance. In space weather forecasting, flare forecasting is an important forecast content. This paper proposes a flare prediction model based on long and short-term memory neural network, which uses the time sequence of magnetic field changes in the solar active region in the past 24 h to construct samples, and analyzes the time series evolution of magnetic field characteristics through the long and short-term memory neural network to predict whether ≥ M-level flares will occur in the next 48 h. This paper uses a data set for all active region samples from May 2010 to May 2017, and selects 10 magnetic field characteristic parameters of SDO/HMI SHARP. In the modeling process, six feature parameters with high weight, gain rate, and coverage rate were selected as input parameters through XGBoost method. Through test comparison, the false report rate and accuracy rate of the model are similar to the traditional machine learning model, and the accuracy rate and critical success index are better than the traditional machine learning model, which are 0.7483 and 0.7402, respectively. The overall effect of the model is better than that of the traditional machine learning model. [ABSTRACT FROM AUTHOR]

A steady-state Monte Carlo scheme is developed for phonon transport based on the energy-based deviational phonon Boltzmann transport equation (PBTE). Other than tracking trajectories and time evolution of each packet in the transient methods, this steady-state method determines the paths of energy packets from being emitted to the steady-state through statistics of scattering probability. By reconsidering and developing the periodic heat flux boundary condition, we extend the capability of this method to systems with arbitrary temperature differences. This steady-state energy-based Monte Carlo (SEMC) method has been verified by comparing predictions with results from the previous discrete-ordinates method, the analytical solution, and transient MC methods for phonon transport in or across thin films. The present SEMC algorithm significantly improves the computational efficiency for a steady phonon transport process instead of time evolution by a transient algorithm. [ABSTRACT FROM AUTHOR]

Metal corrosion exhibits coupled multi-reaction features, making it challenging to quantitatively study the dissolution reaction with variable-valent cations, particularly in valence quantification. This work develops a novel scanning electrochemical microscopy mode and applies it to Ti dissolution study in acidic fluorides. This mode identifies the potential-dependent corrosion reactions and quantifies the valence evolution of Ti from HER to transpassive regions. Results provide direct electrochemical evidence for soluble Ti(z ≤3), for the first time, and revise the reported dissolution equation. The proposed mode overcomes the drawbacks of macro-electrochemical analysis based on coupling information and provides an effective quantitation method for anodic reactions. [Display omitted] • Modified RTG/SC-SECM was proposed to quantitatively study Ti anodic reaction. • Potential-dependent corrosion reaction was identified, implying a coupling feature. • Evolution of dissolution valence was quantified from HER to transpassive regions. • Results provide direct evidence of Ti(z ≤3) products and revise dissolution equation. • This mode is a general mean for dissolution reaction study with multivalent cations. [ABSTRACT FROM AUTHOR]

[Display omitted] • The one-step admicelle to cyclodextrin sweeping method was established. • The approach was applied in the preconcentration of five toxic aristolochic acids. • The method showed low detection limit with 3–6 ng/mL. • The sensitivity enrichment factors of five aristolochic acids was enhanced to 30–68. One-step admicelle to cyclodextrin sweeping (ACDS) method in capillary electrophoresis (CE) has been developed for the separation and preconcentration of toxic aristolochic acids (AAs) by applying cetyltrimethylammonium chloride (CTAC) between the critical micelle concentration and critical surface aggregation concentration. The analytes were captured into the CTAC admicelles, after the more stable inclusion complexes were formed, the release and preconcentration of the analytes could be realized. The CE enrichment parameters, such as the types of cationic surfactants and cyclodextrins (CDs), the concentration of cationic surfactants, disodium tetraborate decahydrate (borax) and CDs, the volume ratio of acetonitrile (ACN) in background electrolyte (BGE) and the sample injection time were optimized systemically. The optimal BGE was composed of 20 mM borax, 10 mM γ-CD and 10 % (v/v) ACN, the sample matrix consisted of 0.2 mM CTAC, 20 mM borax and five analytes. The limit of detection of this method was 3–6 ng/mL, and good linearity values (R2) were obtained for five AAs in the range of 0.997–0.999. Applying optimized conditions, the enrichment efficiencies of five AAs were enhanced with the sensitivity enrichment factors of 30–68. The sweeping approach was successfully applied to the determination of A, B, Ⅶ a , C and D in Aristolochia and Asarum samples, which could provide a potential in the enrichment of the other toxic compounds. [ABSTRACT FROM AUTHOR]

Annals Graphic Medicine brings together original graphic narratives, comics, animation/video, and other creative forms by those who provide or receive health care. They address medically relevant topics—whether they be poignant, thought-provoking, or just plain entertaining. [ABSTRACT FROM AUTHOR]

Lignin, especially Brauns native lignin (BNL), from Chinese quince (Chaenomeles sinensis) fruit represents a potential source of natural antioxidants. However, the highly inhomogeneous structure and the carbohydrate impurity reduce the antioxidant properties of BNL. Accordingly, a sequential aqueous acetone fractionation was used to prepare pure lignin fractions with homogeneous molecular structures; these fractions showed strong antioxidant properties. Analytical results showed that the yields of F 50% and F 60% exceeded 20% (i.e., 20.6% and 24.1%, respectively). The sugar impurities in BNL were mainly retained in the F 30% and F 40% fractions. For all fractions, molecular weight increased as the acetone concentration increased. The results from 2D HSQC NMR and 31P NMR indicated that the number of lignin linkages (β-O-4′, β-β' and β-5′) and functional groups (S-OH, G-OH, H-OH, and COOH) of these fractions varied with their molecular weights. Antioxidant assays showed that F 40% , F 50% and F 60% had higher antioxidant properties than BNL. Overall, the study provides a simple, environmentally friendly fractionation method to prepare lignin with various structural features and strong antioxidant properties from Chinese quince fruit. These lignin fractions have promising application in some fields with high value, such as antioxidants production, biomaterials, packaging materials, and drug delivery and so on. [Display omitted] • Brauns native lignin from Chinese quince fruit is a promising natural antioxidant. • A simple, environmentally friendly method was proposed to fractionate BNL. • Pure and homogeneous BNLs with enhanced antioxidant properties were prepared. • Chinese quince fruit was demonstrated a potentially valuable natural resource. [ABSTRACT FROM AUTHOR]

Background: GC pairs are generally more stable than AT pairs; GC-rich genomes were proposed to be more adapted to high temperatures than AT-rich genomes. Previous studies consistently showed positive correlations between growth temperature and the GC contents of structural RNA genes. However, for the whole genome sequences and the silent sites of the codons in protein-coding genes, the relationship between GC content and growth temperature is in a long-lasting debate. Results: With a dataset much larger than previous studies (681 bacteria and 155 archaea with completely assembled genomes), our phylogenetic comparative analyses showed positive correlations between optimal growth temperature (Topt) and GC content both in bacterial and archaeal structural RNA genes and in bacterial whole genome sequences, chromosomal sequences, plasmid sequences, core genes, and accessory genes. However, in the 155 archaea, we did not observe a significant positive correlation of Topt with whole-genome GC content (GCw) or GC content at four-fold degenerate sites. We randomly drew 155 samples from the 681 bacteria for 1000 rounds. In most cases (> 95%), the positive correlations between Topt and genomic GC contents became statistically nonsignificant (P > 0.05). This result suggested that the small sample sizes might account for the lack of positive correlations between growth temperature and genomic GC content in the 155 archaea and the bacterial samples of previous studies. Comparing the GC content among four categories (psychrophiles/psychrotrophiles, mesophiles, thermophiles, and hyperthermophiles) also revealed a positive correlation between GCw and growth temperature in bacteria. By including the GCw of incompletely assembled genomes, we expanded the sample size of archaea to 303. Positive correlations between GCw and Topt appear especially after excluding the halophilic archaea whose GC contents might be strongly shaped by intense UV radiation. Conclusions: This study explains the previous contradictory observations and ends a long debate. Prokaryotes growing in high temperatures have higher GC contents. Thermal adaptation is one possible explanation for the positive association. Meanwhile, we propose that the elevated efficiency of DNA repair in response to heat mutagenesis might have the by-product of increasing GC content like that happens in intracellular symbionts and marine bacterioplankton. [ABSTRACT FROM AUTHOR]

A novel organic base-assisted (OB-assisted) mechanochemical extraction (MCE) method was established for the efficient extraction of water- and fat-soluble compounds from Ophiopogon japonicus. This study investigated the influence of OB type, amount of OB, grinding time, solid-liquid ratio, vortexing time, and pH. The optimal conditions obtained from the response surface methodology are 124.16 μL of n-butylamine, a grinding time of 6.06 min, and pH of 10.59. In addition, the method showed a good linear relationship (R2 > 0.99), high accuracy (relative standard deviation > 4.44%), and an acceptable recovery rate (89.99–110.52%). The results of scanning electron microscopy suggested that mechanochemical processes may destroy the cell walls and convert the target compounds into water-soluble salt forms in the presence of added OBs. Compared with other methods, the proposed MCE does not use any organic solvent in the extraction medium and reduces the extraction time. It was successfully applied to extract flavonoids and saponins from Ophiopogon japonicus. [Display omitted] • A novel organic base-assisted mechanochemical extraction method was established. • Water is used as a solvent, and no organic solvents are used. • The method can extract hydrophobic and hydrophilic compounds at the same time. • This method can be applied to complex matrixes. • It is an efficient, green and environmentally friendly method. [ABSTRACT FROM AUTHOR]

In spite of big data and new techniques, the phylogeny and timing of cockroaches remain in dispute. Apart from sequencing more species, an alternative way to improve the phylogenetic inference and time estimation is to improve the quality of data, calibrations and analytical procedure. This study emphasizes the completeness of data, the reliability of genes (judged via alignment ambiguity and substitution saturation), and the justification for fossil calibrations. Based on published mitochondrial genomes, the Bayesian phylogeny of cockroaches and termites is recovered as: Corydiinae + (((Cryptocercidae + Isoptera) + ((Anaplectidae + Lamproblattidae) + (Tryonicidae + Blattidae))) + (Pseudophyllodromiinae + (Ectobiinae + (Blattellinae + Blaberidae)))). With two fossil calibrations, namely, Valditermes brenanae and Piniblattella yixianensis, this study dates the crown Dictyoptera to early Jurassic, and crown Blattodea to middle Jurassic. Using the ambiguous 'roachoid' fossils to calibrate Dictyoptera+sister pushes these times back to Permian and Triassic. This study also shows that appropriate fossil calibrations are rarer than considered in previous studies. [ABSTRACT FROM AUTHOR]

The behaviors and kinetics of hydrogen evolution reaction (HER) on pure aluminum with passive film in the presence and absence of chloride ion are quantitatively investigated by using the tip generation/substrate collection mode of scanning electrochemical microscopy (SECM) with dual Al/Pt ultramicroelectrode (UME) as tip electrode and Pt UME as substrate electrode. The standard rate constants k 0 and transfer coefficients α H of HER in ClO 4 −- and Cl−-containing solution are 6.9 × 10−7 cm/s and 0.22, 7.1 × 10−6 cm/s and 0.19, respectively. Results show that the kinetic of HER is slow and the destruction of Cl− on passive film can significantly promote the HER on Al surface. Moreover, these α H far less than commonly used 0.5 in corrosion research, can explain the great difference between theoretical Tafel slopes and experimental results. Besides, the existence of current plateau in Al electrode explains the large difference in corrosion potential during parallel testing. The Al tip and Pt substrate current were recorded by scanning the tip potential from −0.967 V to the positive direction until current suddenly drops in 5 mM HCl +0.1 M NaCl solution (graph on the left). Schematic diagram of distance determination by Fc/Fc+ between Pt tip and Pt substrate electrode in 1 mM FcMeOH +0.1 M KNO 3 solution (dotted line), and the quantitative detection of HER generated on Al surface in deaerated acid solution after moving Al tip above the Pt substrate (solid line), as shown in the middle graph. The Al tip current, hydrogen evolution reaction current and Al oxidation current were recorded in the potential from −0.967 V to 1.333 V in 5 mM HClO 4 + 0.1 M NaClO 4 (graph on the right). [Display omitted] • The kinetics of HER on Al surface was studied by the modified TG/SC mode of SECM. • Kinetic parameters k 0 and transfer coefficients α H of HER are obtained. • HER rate in Cl− ion solution is significantly higher than that in ClO 4 − ion solution. • α H far from 0.5 explains the difference of theoretical β c and experimental results. • The current platform can explain the large difference of E corr during parallel testing. [ABSTRACT FROM AUTHOR]

Background: Quercetin (QUE) is a flavonol reported with anti-inflammatory and antioxidant activities, and previous results from the group of this study have demonstrated its neuroprotective effect against lipopolysaccharide-induced neuropsychiatric injuries. However, little is known about its potential effect on neuropsychiatric injuries induced or accompanied by metabolic dysfunction of glucose and lipids. Methods: A nonalcoholic fatty liver disease (NAFLD) rat model was induced via a high-fat diet (HFD), and glucolipid parameters and liver function were measured. Behavioral performance was observed via the open field test (OFT) and the Morris water maze (MWM). The plasma levels of triggering receptor expressed on myeloid cells-1 (TREM1) and TREM2 were measured via enzyme-linked immunosorbent assay (ELISA). The protein expression levels of Synapsin-1 (Syn-1), Synaptatogmin-1 (Syt-1), TREM1 and TREM2 in the hippocampus were detected using western blotting. Morphological changes in the liver and hippocampus were detected by HE and Oil red or silver staining. Results: Compared with the control rats, HFD-induced NAFLD model rats presented significant metabolic dysfunction, hepatocyte steatosis, and impaired learning and memory ability, as indicated by the increased plasma concentrations of total cholesterol (TC) and triglyceride (TG), the impaired glucose tolerance, the accumulated fat droplets and balloon-like changes in the liver, and the increased escaping latency but decreased duration in the target quadrant in the Morris water maze. All these changes were reversed in QUE-treated rats. Moreover, apart from improving the morphological injuries in the hippocampus, treatment with QUE could increase the decreased plasma concentration and hippocampal protein expression of TREM1 in NAFLD rats and increase the decreased expression of Syn-1 and Syt-1 in the hippocampus. Conclusions: These results suggested the therapeutic potential of QUE against NAFLD-associated impairment of learning and memory, and the mechanism might involve regulating the metabolic dysfunction of glucose and lipids and balancing the protein expression of synaptic plasticity markers and TREM1/2 in the hippocampus. [ABSTRACT FROM AUTHOR]

With the rapid development of Internet of Things technology, the huge network connected by sensors has blend into every corner of the society. Exploring an appropriate power source to drive these sensors is an essential demand. Piezoelectric nanogenerators (PENGs) is considered as a promising approach, which can be employed to convert mechanical energy generated by small-scale physical deformation into electrical output. Herein, we proposed a flexible PENG based on sponge-shaped piezoelectric composite. The open-circuit voltage, short-circuit current and power density of the developed device achieved 33 V, 0.7 μA and 3 mW m−2, respectively. This PENG successfully charged a 10 μF capacitor to 1.8 V in 280 s under the condition that the vibrator applies a continuous compressive force. In addition, experimental measurements to evaluate its actual output performance were well carried out. Resulting from its porous properties, this sponge-shaped PENG possesses higher flexibility and higher output capacity, which provides a promising potential in a variety of applications including energy harvesting and self-powered sensing. [ABSTRACT FROM AUTHOR]

A safe and efficient synthetic method for MB3H8 (M = Na, K, Rb and Cs) has been developed with excellent yields by directly reacting the corresponding MBH4 with the dimethyl sulfide borane complex (DMS·BH3). A general mechanism for constructing B3H8−, a basic unit for building polyhedral boranes, has been unravelled. [ABSTRACT FROM AUTHOR]

A recent genome-wide association study (GWAS) of Asian ancestry reported that single nucleotide polymorphism (SNP) in TERT (telomerase reverse transcriptase) was associated with systemic lupus erythematosus (SLE). TERT has a critical role in maintaining the chromosomal stability and the length of telomere. Given that only a small portion of the genetic heritability of SLE has been explained so far, we aimed to identify novel loci in telomere-related genes responsible for SLE susceptibility in Chinese populations. We performed a comprehensive genetic association analysis of SLE with telomere-related genes. To identify functional significance, we analyzed the publicly available HaploReg v4.1 and RegulomeDB databases. Differential gene expression analysis was also performed using ArrayExpress. A novel signal of PINX1 rs6984094 was identified (Pdiscovery = 4.13 × 10-2, OR = 0.58, 95% CI 0.35-0.98) and successfully replicated (Preplication = 5.73 × 10-3, OR = 0.45, 95% CI 0.26-0.81). Multiple layers of functional analysis suggested that the PINX1 rs6984094 risk T allele exhibited increased nuclear protein binding. We also observed an increased expression of PINX1 mRNA in peripheral blood mononuclear cells from SLE patients compared with healthy controls. Overall, we observed a novel genetic association between PINX1 (encodes the PinX1 protein, an inhibitory telomerase enzyme that lengthens telomeres) and SLE susceptibility in Chinese populations. [ABSTRACT FROM AUTHOR]

A two-stage method for matching private idle parking slots with demanders is proposed based on the core idea of private idle parking slot sharing to solve the problem of parking difficulty in a shared economy environment. This method combines knowledge rules and a multiobjective optimization model. In the first stage, knowledge rules for screening private idle parking slots that meet demanders' walking distance and parking price requirements are proposed. In the second stage, the degree of satisfaction of demanders concerning parking price and walking distance from private idle parking slots to their destination and the degree of satisfaction of private idle parking slots regarding parking slot occupancy rates are constructed first. Then, considering whether private idle parking slot owners provide extended time, a multiobjective optimization model is established by maximizing the satisfaction degree of demanders, the satisfaction degree of private idle parking slot owners, and the profits of the platform. Further, an improved nondominated sorting genetic algorithm II (INSGA II) is developed to solve the model. Finally, a practical example is used to illustrate the feasibility and effectiveness of the proposed method. [ABSTRACT FROM AUTHOR]

Objectives: To evaluate a potential role of albumin-to-globulin ratio (AGR) in the development of lupus nephritis (LN) and determine the potential to use AGR as a marker for future LN in systemic lupus erythematosus (SLE) patients. Methods: 194 newly diagnosed SLE patients without renal impairment were followed. The clinical data were collected and analyzed at the time of initial diagnosis of SLE and the end of follow-up. We compared baseline characteristics between those who did or did not develop LN on follow-up. Univariate and multivariate Cox hazard analysis were used to identify predictors of lupus nephritis. Results: Among the 194 newly diagnosed SLE patients without renal impairment, 26 (13.40%) patients were diagnosed with LN during a median follow-up of 53.87 months. On univariate Cox analysis, patients with the history of alopecia, higher SBP, lower AGR, lower CRP, lower C3, lower C4, higher anti-dsDNA Ab, presence of ANA homogeneous patterns or higher SLEDAI had an increased probability of developing LN. In a multivariate model, the history of alopecia (adjust hazard ratio, aHR = 3.614, 95%CI 1.365-9.571 P = 0.010), lower AGR (aHR = 6.968, 95%CI 1.873-25.919, P = 0.004), lower CRP (aHR = 4.230, 95%CI 1.591-11.247, P = 0.004) and higher level of anti-dsDNA (aHR = 2.675, 95%CI 1.008-7.093, P = 0.048) were independently associated with an increased risk of developing LN after adjusting for covariates. Conclusion: Our findings indicated that SLE patients with low AGR, low CRP, high anti-dsDNA and the history of alopecia were more likely to develop LN in the course of SLE. AGR shown the greatest hazard for developing LN among them, it may be a strong predictor. [ABSTRACT FROM AUTHOR]

Interstitial lung disease (ILD) is a chronic lung dysfunction disease with a poor prognosis and poor recovery. The clinically used therapeutic drugs, such as glucocorticoids and immunosuppressants, have no significant therapeutic effect and are accompanied with severe side effects. In recent years, considerable progress has been made in exploring and applying natural herb components for treating ILD. Traditional Chinese Medicine (TCM) possesses innate, non-toxic characteristics and offers advantages in preventing and treating pulmonary ailments. However, a comprehensive study of TCM on ILD therapy has not yet been reviewed. This review aimed to provide a comprehensive summary of the monomer components, total extracts, and prescriptions of TCM for ILD therapy, elucidating their molecular mechanisms to serve as a reference in treating ILD. The literature information was searched in the PubMed, Web of Science databases. The search keywords included 'interstitial lung disease', 'lung fibrosis' or 'pulmonary fibrosis', and 'traditional Chinese medicine', 'traditional herbal medicine', or 'herb medicine'. The active components of single herbs, such as alkaloids, flavonoids, terpenoids, phenols, and quinones, have potential therapeutic effects on ILD. The active extracts and prescriptions were also summarized and analyzed. The herbs, Glycyrrhiza uralensis Fisch. (Gancao), Astragalus membranaceus Fisch. Bunge. (Huangqi) and Angelicasinensis (Oliv.) Diels (Danggui), play significant roles in the treatment of ILD. The mechanisms involve the inhibition of inflammatory factor release, anti-oxidative injury, and interference with collagen production, etc. This review examines the therapeutic potential of TCM for ILD and elucidates its molecular mechanisms, demonstrating that mitigating inflammation and oxidative stress, modulating the immune system, and promoting tissue repair are efficacious strategies for ILD therapy. The depth research will yield both theoretical and practical implications. [Display omitted] • The active components derived from TCM have potential therapeutic effects against ILD. • The total extract from TCM is effective for the treatment of ILD. • The therapeutic mechanisms of TCM for ILD include anti-inflammatory, antioxidant and immunomodulatory effects. [ABSTRACT FROM AUTHOR]

In drug delivery systems, graphene materials are promising drug carriers. Drug molecules are loaded on graphene through π-π interaction between graphene and benzene ring structure, which is widely found in organic drug molecules. Then the drug molecules are released under different conditions, such as different environmental pH, at lesion site. In the application, the adsorption and desorption between benzene ring structure in drug molecules and graphene play a key role. Herein, an experimental method for measuring the adhesion force between a single phenyl and graphene is proposed, and the adsorption and desorption mechanical properties of a benzene ring structure on graphene surface at different environmental pH are firstly measured. The experimental results show that the adhesion force decreases with the increase of environmental pH. Moreover, molecular dynamics simulations show that the influence of pH on adhesion force is mainly realized by changing the electrostatic potential distribution on graphene surface, and the interaction force between a single benzene and graphene changes from attractive to repulsive with the increase of environmental alkalinity. In addition, a molecular dynamics model for the dynamic adsorption and desorption capacities of benzene molecules on graphene surface at different quantity of ions is established. Benzene molecules can achieve full adsorption on the surface of graphene when there are 10 and 20 hydrogen ions. And benzene molecules can achieve full desorption on the surface of graphene when there are 10 and 20 hydroxide ions. [Display omitted] [ABSTRACT FROM AUTHOR]

The current research on the corrosion resistance of high entropy alloys (HEAs), mainly focuses on the influence of element composition and percentage difference. Considering the almost consistent passivation range with different corrosion resistance contributed by element addition, it inevitably exists obvious differences the passive film properties. The effect of passive film on corrosion behavior of HEA is worthy to be investigated in detail. Considering the microstructure transformation detected by electron probe X-ray microanalysis (EPMA) and surface feedback effect measured by approach curve of scanning electrochemical microscopy (SECM), the passivity of Al x (CoCrFeNi) 100-x (x = 0–20) HEAs in 0.5 M H 2 SO 4 solution has been investigated by cyclic potentiodynamic polarization, electrochemical impedance spectroscopy (EIS), Mott-Schottky analysis and X-ray photoelectron spectroscopy (XPS). The results demonstrate that the passive film is thick and dense at low Al content (5%), which shows excellent corrosion resistance. However, with the increase of Al content, the corrosion resistance of passive film deteriorates gradually. XPS are adopted to detect film composition to explain the reason of film property change. The results suggest that there are more oxidized states of Al and less oxidized states of Cr in the passive film of HEAs with Al addition. The dominate semiconductor characteristics of Al x (CoCrFeNi) 100-x with Al addition change from p-type to n-type. All results indicate that the addition of Al has a significantly influence on the composition and properties of passive film on the Al x (CoCrFeNi) 100-x alloys surface. • The corrosion resistance and semiconductor characterization of passive film on Al x (CoCrFeNi) 100-x was studied. • The phase constituents of Al x (CoCrFeNi) 100-x change from single FCC phase to BCC phases as more Al is being added. • A small amount of Al without phase transformation is beneficial to stabilize a thick and compact passive film. • The passive film semiconductor characteristic of Al x (CoCrFeNi) 100-x with Al addition is predominant from p-type to n-type. [ABSTRACT FROM AUTHOR]

Objectives: Clinical benefits of immune-checkpoint blockade (ICB) versus standard chemotherapy have been established in unselected non-small cell lung cancer (NSCLC). However, the response to ICB therapy among patients is heterogeneous in clinical practice. Materials and Methods: We retrospectively assessed the predicitive effect of the primary and metastatic lesion spectrum (baseline sum of the longest diameters [SLD], number of metastatic sites and specific organ metastases) on the efficacy of atezolizumab over docetaxel in OAK and POPLAR trial cohorts. A decision model, termed DSO (Diameter-Site-Organ), based on the spectrum was developed and validated for guiding ICB. Results: Higher SLD (>38 mm) and more metastatic sites (>2) were characterized with pronounced overall survival (OS) benefits from atezolizumab versus docetaxel. Specifically, adrenal gland and brain metastases were identified as favorable predictors of atezolizumab treatment. The DSO model was developed in the discovery cohort to integrate the directive effect of the primary and metastatic lesion spectrum. Remarkably, a general pattern of enhanced efficacy of atezolizumab versus docetaxel was observed along with the increase of the DSO score. For patients with DSO score > 0, atezolizumab yielded a significantly prolonged OS than docetaxel, whereas OS was generally similar between two treatments in patients with DSO score < 0. Equivalent findings were also seen in the internal and external validation cohorts. Conclusions: The response to anti-PD-LI therapy among patients varied with the primary and metastatic lesion spectrum. The DSO-based system might provide promising medication guidance for ICB treatment in NSCLC patients. [ABSTRACT FROM AUTHOR]

Chinese quince fruits (Chaenomeles sinensis) have an abundance of lignins with antioxidant activities. To facilitate the utilization of Chinese quince fruits, lignin was isolated from it by auto-catalyzed ethanol organosolv pretreatment. The effects of three processing conditions (temperature, time, and ethanol concentration) on yield, structural features and antioxidant activities of the auto-catalyzed ethanol organosolv lignin samples were assessed individually. Results showed the pretreatment temperature was the most significant factor; it affected the molecular weight, S/G ratio, number of β-O-4′ linkages, thermal stability, and antioxidant activities of lignin samples. According to the GPC analyses, the molecular weight of lignin samples had a negative correlation with pretreatment temperature. 2D-HSQC NMR and Py-GC/MS results revealed that the S/G ratios of lignin samples increased with temperature, while total phenolic hydroxyl content of lignin samples decreased. The structural characterization clearly indicated that the various pretreatment conditions affected the structures of organosolv lignin, which further resulted in differences in the antioxidant activities of the lignin samples. These results can be helpful for controlling and optimizing delignification during auto-catalyzed ethanol organosolv pretreatment, and they provide theoretical support for the potential applications of Chinese quince fruits lignin as a natural antioxidant in the food industry. Unlabelled Image • Organosolv pretreatment was used to separate lignin from Chinese quince fruits. • The pretreatment condition of maximum lignin yield: 200 °C, 90 min, and 60% ethanol. • Pretreatment temperature was the most significant factor to affect lignin structure. • Lignin samples extracted at lower temperatures showed stronger antioxidant activity. [ABSTRACT FROM AUTHOR]

The Theological property evolution of polyamide 1012 (PA1012) in the isothermal process in molten state has been investigated. The results show that the viscosity increases and crosslinking reaction occurs simultaneously together with the increase of temperature, thus causing the variation of storage modulus (G′) and loss modulus (G″) in the repeated frequency sweeps with residual time. This research has pointed out that the superposition is valid for monitoring the complex behavior composed of the viscosity increasing and crosslink occurring process by tracing the variation behavior of the crossover points of G' and G" with time, revealing the same time-temperature dependence of the two reactions in the isothermal process. A normalized master curve has been proposed to describe the melt behavior at a given temperature. [ABSTRACT FROM AUTHOR]

The anticipated increasing demand for inactivated foot-and-mouth (FMD) disease vaccine calls for its larger production capacity, while development of a large-scale process typically requires high running cost and has very limited experimental throughput at manufacturing scale. Thus, an economic scale-down model of representing a large-scale process becomes necessary and essential. In this study, we used a systematic approach to establish a scale-down model representing a 4000-L culture process for FMD vaccine production by suspension BHK-21 cells. In detail, we firstly compared hydrodynamic properties of three bioreactors (14-L, 800-L and 4000-L) under three different conditions (equivalent mixing time, equivalent shear stress and equivalent volumetric power). We figured out equivalent volumetric power (P / V) potentially as an appropriate scale-down strategy, since it resulted in comparable calculated hydrodynamic parameters among three bioreactors. Next, we used computational fluid dynamics (CFD) simulation to provide more details about hydrodynamic environments inside the bioreactors, which supports the reliability of this scale-down strategy. Finally, we compared cell growth, metabolites, vaccine productivity and product quality attributes during FMD vaccine production by BHK-21 cells and observed very close performances among three bioreactors, which once again demonstrates the robustness of this scale-down model. This scale-down strategy can be applied to study variations and critical quality attributes (CQAs) in the resultant production process based on quality by design (QbD) principles, aiming at further more efficient optimization of vaccine production. [ABSTRACT FROM AUTHOR]

Objective Breast cancer is a malignant tumor in the epithelial tissue of the breast gland. This study aimed to unveil the expression and clinical diagnostic value of lncRNA cervical cancer high-expressed 1 (CCHE1) in breast cancer. Methods CCHE1 expression in breast cancer tissues was evaluated by RT-qPCR. The relationship between the CCHE1 expression and clinicopathological features of breast cancer was analyzed with the chi-square test, and the survival of breast cancer patients was evaluated with the Kaplan–Meier method. The diagnostic value of CCHE1 expression for breast cancer was evaluated by using the receiver operating characteristics (ROC) curve. Breast cancer cell lines (SKBR3, T47D, BT474, and MCF-7) were cultured for detecting CCHE1 expression in the cells. MCF-7 cells were selected for the subsequent experiments, and the small interfering RNA of CCHE1 (si-CCHE1) and CCHE1 overexpression vector (pcDNA-CCHE1) were transfected into MCF-7 cells. The proliferation, migration, and invasive ability were assessed by CCK-8 and Transwell assays. The influence of CCHE1 on the growth of tumors was validated by nude mice xenograft assay. Results CCHE1 was up-regulated in breast cancer tissues and breast cancer cells. The high expression level of CCHE1 in cancer tissues of breast cancer patients was correlated with larger tumor size, advanced TNM stage, Ki-67 status, and lymph node metastasis. The area under the ROC curve for CCHE1 in the diagnosis of breast cancer was 0.983 (95% CI: 0.966–1.000), with a sensitivity of 95.00% and a specificity of 91.70%. The 5-year survival rate was higher in patients with low CCHE1 expression than those with high CCHE1 expression. Furthermore, restrained CCHE1 impeded proliferation, invasion, and migration of MCF-7 cells, as well as tumor growth in mice. Conclusion Our study highlights that elevated expression of CCHE1 in breast cancer tissues, which is closely related to clinicopathologic features, has some clinical value in the diagnosis of the disease. [ABSTRACT FROM AUTHOR]

Background: In time‐of‐flight PET, image quality and accuracy can be enhanced by improving the annihilation photon pair coincidence time resolution, which is the variation in the arrival time difference between the two annihilation photons emitted from each positron decay in the patient. Recent studies suggest direct detection of ionization tracks and their resulting modulation of optical properties, instead of scintillation, can improve the CTR significantly, potentially down to less than 10 ps CTR. However, the arrival times of the 511 keV photons are not predictable, leading to challenges in the spatiotemporal localization characterization of the induced charge carriers in the detector crystal. Purpose: To establish an optimized experimental setup for measuring ionization induced modulation of optical properties, it is critical to develop a versatile simulation algorithm that can handle multiple detector material properties and time‐resolved charge carrier dynamics. Methods: We expanded our previous algorithm and simulated ionization tracks, cascade time and induced charge carrier density over time in different materials. For designing a proof‐of‐concept experiment, we simulated ultrafast electrons and free‐electron x‐ray photons for timing characterization along with alpha and beta particles for higher spatial localization. Results: With 3 MeV ultrafast electrons, by reducing detector crystal thickness, we can effectively reduce the ionization cascade time to 0.79 ps and deposited energy to 198.5 keV, which is on the order of the desired 511 keV energy. Alpha source simulations produced a cascade time of 2.45 ps and charge carrier density of 6.39 × 1020 cm−3. Compared to the previous results obtained from 511 keV photon‐induced ionization track simulations, the cascade time displayed similar characteristics, while the charge density was found to be higher. These findings suggest that alpha sources have the potential to generate a stronger ionization‐induced signal using the modulation of optical properties as the detection mechanism. Conclusions: This work provides a guideline to understand, design and optimize an experimental platform that is highly sensitive and temporally precise enough to detect single 511 keV photon interactions with a goal to advance CTR for ToF‐PET. [ABSTRACT FROM AUTHOR]

The phytohormone auxin is implied in steering various developmental decisions during plant morphogenesis in a concentration-dependent manner. Auxin maxima have been shown to maintain meristematic activity, for example, of the root apical meristem, and position new sites of outgrowth, such as during lateral root initiation and phyllotaxis. More recently, it has been demonstrated that sites of auxin minima also provide positional information. In the developing Arabidopsis fruit, auxin minima are required for correct differentiation of the valve margin. It remains unclear, however, how this auxin minimum is generated and maintained. Here, we employ a systems biology approach to model auxin transport based on experimental observations. This allows us to determine the minimal requirements for its establishment. Our simulations reveal that two alternative processes—which we coin "flux-barrier" and "flux-passage"—are both able to generate an auxin minimum, but under different parameter settings. Both models are in principle able to yield similar auxin profiles but present qualitatively distinct patterns of auxin flux. The models were tested by tissue-specific inducible ablation, revealing that the auxin minimum in the fruit is most likely generated by a flux-passage process. Model predictions were further supported through 3D PIN localization imaging and implementing experimentally observed transporter localization. Through such an experimental–modeling cycle, we predict how the auxin minimum gradually matures during fruit development to ensure timely fruit opening and seed dispersal. We investigate the mechanism leading to a spatially confined auxin minimum required for Arabidopsis fruit opening and seed dispersal. Our experiment–modeling cycle reveals a counterintuitive mechanism of its formation: efflux activity creates an auxin minimum strip that is accompanied by high auxin fluxes crossing it perpendicularly. This dynamical process can be associated with the maturation of the fruit. [ABSTRACT FROM AUTHOR]

An efficient synthetic method for MB3H8 (M = Li and Na) has been developed with improved yields on the basis of the investigation of the interconversion between THF·B3H7 and corresponding MB3H8. The mechanism was tentatively proposed based on the understanding of the nucleophilicity of the B–H bonding pair electrons. [ABSTRACT FROM AUTHOR]

Background: Among the four bases, guanine is the most susceptible to damage from oxidative stress. Replication of DNA containing damaged guanines results in G to T mutations. Therefore, the mutations resulting from oxidative DNA damage are generally expected to predominantly consist of G to T (and C to A when the damaged guanine is not in the reference strand) and result in decreased GC content. However, the opposite pattern was reported 16 years ago in a study of prokaryotic genomes. Although that result has been widely cited and confirmed by nine later studies with similar methods, the omission of the effect of shared ancestry requires a re-examination of the reliability of the results. Results: When aerobic and obligate aerobic prokaryotes were mixed together and anaerobic and obligate anaerobic prokaryotes were mixed together, phylogenetic controlled analyses did not detect significant difference in GC content between aerobic and anaerobic prokaryotes. This result is consistent with two generally neglected studied that had accounted for the phylogenetic relationship. However, when obligate aerobic prokaryotes were compared with aerobic prokaryotes, anaerobic prokaryotes, and obligate anaerobic prokaryotes separately using phylogenetic regression analysis, a significant positive association was observed between aerobiosis and GC content, no matter it was calculated from whole genome sequences or the 4-fold degenerate sites of protein-coding genes. Obligate aerobes have significantly higher GC content than aerobes, anaerobes, and obligate anaerobes. Conclusions: The positive association between aerobiosis and GC content could be attributed to a mutational force resulting from incorporation of damaged deoxyguanosine during DNA replication rather than oxidation of the guanine nucleotides within DNA sequences. Our results indicate a grade in the aerobiosis-associated mutational force, strong in obligate aerobes, moderate in aerobes, weak in anaerobes and obligate anaerobes. [ABSTRACT FROM AUTHOR]

Abstract With the combination of two evolutionary algorithms EDA and DE, a new method of initial orbit determination for satellites based on ground-based too-short-arc is established. Compared with other algorithms, the proposed method focuses on the most densely populated region in the solution space rather than the individual with best fitness value. Both the global information and local information are well fused in the search of optimum. In the method (a , e , M) are treated as variables of the optimization, and the optimization procedure is carried out as a two-stage hierarchical optimization problem which has three variables for each stage. Kernel density estimation is applied to build the probability distribution model without any assumptions of the specified distribution, accompanied by handling semi-major axis and eccentricity as a pair of dependent variables in the construction of the probability for the correlation between them in the practice. Numerical experiments with real ground-based observations show that the proposed method is applicable to too-short-arc with even 3 s, and the result of bias in several kilometers can be achieved with 5 ″ error added to angular measurements. [ABSTRACT FROM AUTHOR]

The Comstock-Needham system, the foundation of main vein homology of insects, is grounded in the comparison between wing venation and wing-pad tracheation, particularly that of Plecoptera and Blattodea. However, the trachea-based approach has come into great dispute in recent years. Meanwhile, the terminology used to describe the wing venation of cockroaches requires a revision according to homology and the practical need. These motivated us to examine the wings of cockroaches, comparing the tracheation of nymphs with the tracheation and venation of adults. We find a correspondence between the tracheation and the main vein venation; therefore the trachea-based approach is effective in cockroaches. It is supported that Neopteran insects have six homologous main veins, namely, Sc, R, M, Cu, Pcu and V. We interpret the wing morphology of cockroaches in detail, including veins, furrows, folds and apical folding. RA and RP in hindwing, ScP, CuA and CuP in tegmen and hindwing, are recognized. Hindwing R + M is the only normal venal fusion in cockroaches. In addition, we propose several descriptive terms: cmv, V[1], V[s], pseudostem and characteristic posterior branch. The venation of 41 species (representing 41 genera), and the wing-pad tracheation of four of them including Diploptera punctata, which has unique apical folding, are illustrated. [ABSTRACT FROM AUTHOR]