Optical single-sideband (OSSB) Raman laser system based on an atomic filter for atom gravimeters.

Phase-modulator-generated laser for Raman transition is widely used in atom gravimeters to simplify a system and improve robustness. However, the induced additional sidebands (ASBs) lead to systematic errors in gravity measurement. This work presents a novel, to our knowledge, method to generate an optical single-sideband (OSSB) laser for Raman transition through phase modulation based on a Faraday anomalous dispersion atomic filter (FADOF). The experimental result indicates that it can reduce the additional sidebands with a signal-to-noise ratio (SNR, the intensity ratio of carrier and unwanted sidebands) of better than 50 dB, and the phase shift caused by ASBs is demonstrated to be effectively suppressed from 358.8 to 2.2 mrad. Furthermore, this system has already been applied on an atom gravimeter to achieve a primary gravity measurement. It shows that the FADOF-based Raman laser system is a new scheme for a compact atom absolute gravimeter.

SAD2 functions in plant pathogen Pseudomonas syringae pv tomato DC3000 defense by regulating the nuclear accumulation of MYB30 in Arabidopsis thaliana.

Accurate nucleocytoplasmic transport of signal molecules is essential for plant growth and development. Multiple studies have confirmed that nucleocytoplasmic transport and receptors are involved in regulating plant disease resistance responses, however, little is known about the regulatory mechanism in plants. In this study, we showed that the mutant of the importin beta-like protein SAD2 exhibited a more susceptible phenotype than wild-type Col-0 after treatment with Pseudomonas syringae pv tomato DC3000 (Pst DC3000). Coimmunoprecipitation (Co-IP) and bimolecular fluorescence complementation (BiFC) experiments demonstrated that SAD2 interacts with the hypersensitive response (HR)-positive transcriptional regulator MYB30. Subcellular localization showed that MYB30 was not fully localized in the nucleus in sad2-5 mutants, and western-blot experiments further indicated that SAD2 was required for MYB30 nuclear trafficking during the pathogen infection process. A phenotypic test of pathogen inoculation demonstrated that MYB30 partially rescued the disease symptoms of sad2-5 caused by Pst DC3000, and that MYB30 worked downstream of SAD2 in plant pathogen defense. These results suggested that SAD2 might be involved in plant pathogen defense by mediating MYB30 nuclear trafficking. Taken together, our results revealed the important function of SAD2 in plant pathogen defense and enriched understanding of the mechanism of nucleocytoplasmic transport-mediated plant pathogen defense.

The TRIM21-FOXD1-BCL-2 axis underlies hyperglycaemic cell death and diabetic tissue damage.

Chronic hyperglycaemia is a devastating factor that causes diabetes-induced damage to the retina and kidney. However, the precise mechanism by which hyperglycaemia drives apoptotic cell death is incompletely known. Herein, we found that FOXD1, a FOX family transcription factor specifically expressed in the retina and kidney, regulated the transcription of BCL-2, a master regulator of cell survival. Intriguingly, the protein level of FOXD1, which responded negatively to hyperglycaemic conditions, was controlled by the TRIM21-mediated K48-linked polyubiquitination and subsequent proteasomal degradation. The TRIM21-FOXD1-BCL-2 signalling axis was notably active during diabetes-induced damage to murine retinal and renal tissues. Furthermore, we found that tartary buckwheat flavonoids effectively reversed the downregulation of FOXD1 protein expression and thus restored BCL-2 expression and facilitated the survival of retinal and renal tissues. In summary, we identified a transcription factor responsible for BCL-2 expression, a signalling axis (TRM21-FOXD1-BCL-2) underlying hyperglycaemia-triggered apoptosis, and a potential treatment for deleterious diabetic complications.

A fast breeding strategy creates fragrance- and anthocyanin-enriched rice lines by marker-free gene-editing and hybridization.

As rice is a staple food for nearly half of the world's population, rice varieties with excellent agronomic traits as well as high flavor and nutritional quality such as fragrant rice and purple rice are naturally favored by the market. In the current study, we adopt a fast breeding strategy to improve the aroma and anthocyanin content in the excellent rice inbred line, F25. The strategy skillfully used the advantages of obtaining editing pure lines in T0 generation of CRISPR/Cas9 editing system and easy observation of purple character and grain shape, integrated the subsequent screening of non-transgenic lines, and the elimination of undesirable edited variants from gene-editing and cross-breeding at the same time as the separation of the progeny from the purple cross, thus expediting the breeding process. Compared with conventional breeding strategies, this strategy saves about 6-8 generations and reduces breeding costs. Firstly, we edited the OsBADH2 gene associated with rice flavor using an Agrobacterium-mediated CRISPR/Cas9 system to improve the aroma of F25. In the T0 generation, a homozygous OsBADH2-edited F25 line (F25B) containing more of the scented substance 2-AP was obtained. Then, we crossed F25B (♀) with a purple rice inbred line, P351 (♂), with high anthocyanin enrichment to improve the anthocyanin content of F25. After nearly 2.5 years of screening and identification over five generations, the undesirable variation characteristics caused by gene-editing and hybridization and the transgenic components were screened out. Finally, the improved F25 line with highly stable aroma component, 2-AP, increased anthocyanin content and no exogenous transgenic components were obtained. This study not only provides high-quality aromatic anthocyanin rice lines that meet the market demand, but also offers a reference for the comprehensive use of CRISPR/Cas9 editing technology, hybridization, and marker-assisted selection to accelerate multi-trait improvement and breeding process. Supplementary Information: The online version contains supplementary material available at 10.1007/s11032-023-01369-1.

Racial and Ethnic Disparities in All-Cause and Cardiovascular Mortality Among Cancer Patients in the U.S.

Background: With improved cancer survival, death from noncancer etiologies, especially cardiovascular disease (CVD) mortality, has come more into focus. Little is known about the racial and ethnic disparities in all-cause and CVD mortality among U.S. cancer patients. Objectives: This study sought to investigate racial and ethnic disparities in all-cause and CVD mortality among adults with cancer in the United States. Methods: Using the Surveillance, Epidemiology, and End Results (SEER) database from years 2000 to 2018, all-cause and CVD mortality among patients ≥18 years of age at the time of initial malignancy diagnosis were compared by race and ethnicity groups. The 10 most prevalent cancers were included. Cox regression models were used to estimate adjusted HRs for all-cause and CVD mortality using Fine and Gray's method for competing risks, as applicable. Results: Among a total of 3,674,511 participants included in our study, 1,644,067 (44.7%) died, with 231,386 (6.3%) deaths as a result of CVD. After adjusting for sociodemographic and clinical characteristics, non-Hispanic (NH) Black individuals had both higher all-cause (HR: 1.13; 95% CI: 1.13-1.14) and CVD (HR: 1.25; 95% CI: 1.24-1.27) mortality, whereas Hispanic and NH Asian/Pacific Islander had lower mortality than NH White patients. Racial and ethnic disparities were more prominent among patients 18 to 54 years of age and those with localized cancer. Conclusions: Significant racial and ethnic differences exist in both all-cause and CVD mortality among U.S. cancer patients. Our findings underscore the vital roles of accessible cardiovascular interventions and strategies to identify high-risk cancer populations who may benefit most from early and long-term survivorship care.

Genome-Wide Analysis of MYB Transcription Factor Gene Superfamily Reveals BjPHL2a Involved in Modulating the Expression of BjCHI1 in Brassica juncea.

Brassica juncea is an economically important vegetable and oilseed crop. The MYB transcription factor superfamily is one of the largest transcription factor families in plants, and plays crucial roles in regulating the expression of key genes involved in a variety of physiological processes. However, a systematic analysis of the MYB transcription factor genes in Brassica juncea (BjMYB) has not been performed. In this study, a total of 502 BjMYB superfamily transcription factor genes were identified, including 23 1R-MYBs, 388 R2R3-MYBs, 16 3R-MYBs, 4 4R-MYBs, 7 atypical MYBs, and 64 MYB-CCs, which is approximately 2.4-fold larger than that of AtMYBs. Phylogenetic relationship analysis revealed that the MYB-CC subfamily consists of 64 BjMYB-CC genes. The expression pattern of members of PHL2 subclade homologous genes in Brassica juncea (BjPHL2) after Botrytis cinerea infection were determined, and BjPHL2a was isolated from a yeast one-hybrid screen with the promoter of BjCHI1 as bait. BjPHL2a was found to localize mainly in the nucleus of plant cells. An EMSA assay confirmed that BjPHL2a binds to the Wbl-4 element of BjCHI1. Transiently expressed BjPHL2a activates expression of the GUS reporter system driven by a BjCHI1 mini-promoter in tobacco (Nicotiana benthamiana) leaves. Taken together, our data provide a comprehensive evaluation of BjMYBs and show that BjPHL2a, one of the members of BjMYB-CCs, functions as a transcription activator by interacting with the Wbl-4 element in the promoter of BjCHI1 for targeted gene-inducible expression.

Rutin alleviates colon lesions and regulates gut microbiota in diabetic mice.

Diabetes is a common metabolic disorder that has become a major health problem worldwide. In this study, we investigated the role of rutin in attenuating diabetes and preventing diabetes-related colon lesions in mice potentially through regulation of gut microbiota. The rutin from tartary buckwheat as analyzed by HPLC was administered intragastrically to diabetic mice, and then the biochemical parameters, overall community structure and composition of gut microbiota in diabetic mice were assayed. The results showed that rutin lowered serum glucose and improved serum total cholesterol, low-density lipoprotein, high-density lipoprotein, triglyceride concentrations, tumor necrosis factor-α, interleukin-6, and serum insulin in diabetic mice. Notably, rutin obviously alleviated colon lesions in diabetic mice. Moreover, rutin also significantly regulated gut microbiota dysbiosis and enriched beneficial microbiota, such as Akkermansia (p < 0.05). Rutin selectively increased short-chain fatty acid producing bacteria, such as Alistipes (p < 0.05) and Roseburia (p < 0.05), and decreased the abundance of diabetes-related gut microbiota, such as Escherichia (p < 0.05) and Mucispirillum (p < 0.05). Our data suggested that rutin exerted an antidiabetic effect and alleviated colon lesions in diabetic mice possibly by regulating gut microbiota dysbiosis, which might be a potential mechanism through which rutin alleviates diabetes-related symptoms.

Novel Radiotracers for Molecular Imaging of Myocardial Inflammation: an Update Focused on Clinical Translation of Non-18F-FDG Radiotracers.

Purpose of Review: The purpose of this paper is to provide a focused update on recent advances in non-18F-FDG radiotracers for myocardial inflammatory diseases, with a focus on cardiac sarcoidosis and myocarditis. Recent Findings: Novel radiotracers targeting molecular features of inflammation have the potential to visualize underlying molecular mechanisms key to the pathogenesis of inflammatory cardiomyopathies such as sarcoidosis and myocarditis. These radiotracers may provide unique opportunities for improved mechanistic insight, higher specificity, and better quantification of disease activity, as well as potential for guidance and monitoring of immunomodulatory therapies. Summary: Novel radiotracers provide unique possibilities in diagnosis, prognostic performance, and therapy guidance for cardiac sarcoidosis and myocarditis.

Transcriptomic Analysis Revealed Key Defense Genes and Signaling Pathways Mediated by the Arabidopsis thaliana Gene SAD2 in Response to Infection with Pseudomonas syringae pv. Tomato DC3000.

Nucleocytoplasmic transport receptors play key roles in the nuclear translocation of disease resistance proteins, but the associated mechanisms remain unclear. The Arabidopsis thaliana gene SAD2 encodes an importin ß-like protein. A transgenic Arabidopsis line overexpressing SAD2 (OESAD2/Col-0) showed obvious resistance to Pseudomonas syringae pv. tomato DC3000 (Pst DC3000) compared to the wild type (Col-0), but the knockout mutant sad2-5 was susceptible. Transcriptomic analysis was then performed on Col-0, OESAD2/Col-0, and sad2-5 leaves at 0, 1, 2, and 3 days post-inoculation with Pst DC3000. A total of 1825 differentially expressed genes (DEGs) were identified as putative biotic stress defense genes regulated by SAD2, 45 of which overlapped between the SAD2 knockout and overexpression datasets. Gene Ontology (GO) analysis indicated that the DEGs were broadly involved in single-organism cellular metabolic processes and in response to stimulatory stress. Kyoto Encyclopedia of Genes and Genomes (KEGG) biochemical pathway analysis revealed that many of the DEGs were associated with the biosynthesis of flavonoids and other specialized metabolites. Transcription factor analysis showed that a large number of ERF/AP2, MYB, and bHLH transcription factors were involved in SAD2-mediated plant disease resistance. These results provide a basis for future exploration of the molecular mechanisms associated with SAD2-mediated disease resistance and establish a set of key candidate disease resistance genes.

Efficacy and Mechanism of Roxadustat plus Oral Iron in the Treatment of Elderly Chronic Kidney Disease with Anemia.

Objective: For investigating the efficacy and mechanism of Roxadustat + oral iron in the treatment of elderly chronic kidney disease (CKD) complicated with anemia. Methods: A total of 100 elderly patients with CKD and anemia admitted to our hospital between April 2020 and December 2021 were enrolled as research subjects, and the patients were assigned to control group (Con group, n = 50) or experimental group (Exp group, n = 50). The patients in the Con group were given oral iron, and those in the Exp group were given Roxadustat capsule based on the Con group. Both groups were given subcutaneous injection of recombinant human erythropoietin. The clinical efficacy, anemia indexes, iron metabolism indexes, inflammatory indexes, and adverse reactions were compared between the two groups. Results: The Exp group showed a notably higher treatment effective rate than the Con group (P < 0.05). After treatment, the anemia indexes, iron metabolism indexes, and inflammatory indexes in the Exp group were notably better than those in the Con group (P < 0.05). The Exp group showed a notably lower incidence of adverse reactions during treatment than the Con group (P < 0.05). Conclusion: Roxadustat plus oral iron yields a pronounced clinical efficacy in the therapy of elderly patients with CKD and anemia.

Detection of Bartonella vinsonii subsp. berkhoffii in an HIV patient using metagenomic Next-Generation Sequencing.

Bartonella species are fastidious, aerobic bacteria that are transmitted by blood-sucking arthropods. Bartonella spp. are responsible for cat scratch disease, Carrion's disease, bacillary angiomatosis and trench fever. On the other hand, Bartonella vinsonii is rarely reported in the literature and there exist a few reports of systemic infection caused by Bartonella vinsonii in patients with acquired immunodeficiency syndrome. A 31-year-old male (diagnosed with AIDS six years ago) had persistent fever and ulceration in the right knee. The elevated levels of inflammatory markers suggested an infectious aetiology. Despite the negative findings of blood culture, metagenomic Next-Generation Sequencing of plasma detected Bartonella vinsonii. The polymerase chain reaction of whole blood and Sanger sequencing confirmed the mNGS findings. Immunohistochemical staining had later suggested bacillary angiomatosis, which was consistent with Bartonella infection. Following antibiotic treatment, the ulcers subsided significantly, but a high fever persisted. The patient died due to sudden respiratory failure.

Rutin Promotes Pancreatic Cancer Cell Apoptosis by Upregulating miRNA-877-3p Expression.

(1) Background: pancreatic cancer is one of the most serious cancers due to its rapid and inevitable fatality, which has been proved very difficult to treat, compared with many other common cancers. Thus, developing an effective therapeutic strategy, especially searching for potential drugs, is the focus of current research. The exact mechanism of rutin in pancreatic cancer remains unknown. (2) Method: three pancreatic cancer cell lines were used to study the anti-pancreatic cancer effect of rutin. The potent anti-proliferative, anti-migration and pro-apoptotic properties of rutin were uncovered by cell viability, a wound-healing migration assay, and a cell apoptosis assay. High-throughput sequencing technology was used to detect the change of miRNAs expression. Immunoblotting analysis was used to detect the expression of apoptotic proteins. (3) Results: CCK-8 and EDU assays revealed that rutin significantly inhibited pancreatic cancer cells' proliferation (p < 0.05). A wound-healing assay showed that rutin significantly suppressed pancreatic cancer cells' migration (p < 0.05). A flow cytometric assay showed that rutin could promote pancreatic cancer cells' apoptosis. Intriguingly, rutin significantly upregulated miR-877-3p expression to repress the transcription of Bcl-2 and to induce pancreatic cancer cell apoptosis. Accordingly, rutin and miR-877-3p mimics could promote apoptotic protein expression. (4) Conclusions: our findings indicate that rutin plays an important role in anti-pancreatic cancer effects through a rutin-miR-877-3p-Bcl-2 axis and suggests a potential therapeutic strategy for pancreatic cancer.

Effect of Carbon on Dislocation Loops Formation during Self-Ion Irradiation in Fe-Cr Alloys at High Temperatures.

In this study, two types of ferritic model alloys (Fe-9Cr and Fe-9Cr-C) were simultaneously irradiated with 3.5 MeV Fe13+ ions at 450 °C and 550 °C to a dose of 3dpa at the peak damage region, respectively. Transmission electron microscopy (TEM) was used to investigate the microstructural evolution of the Fe-Cr alloys after irradiation. The experimental results showed that the size of the dislocation loops formed in the Fe-9Cr-C alloy was larger than that in the Fe-9Cr alloy, but the loop density of the Fe-9Cr-C alloy was lower than that of the Fe-9Cr alloy after irradiation at 450 °C. The reason for this phenomenon was attributed to the fact that loops formed in Fe-9Cr-C alloy have greater capture efficiency for interstitial atoms. Compared to Fe-Cr alloys irradiated at 450 °C, high-density loops were not observed in the Fe-Cr alloys irradiated at 550 °C; the number of dislocation loops in the Fe-Cr alloys irradiated at 550 °C significantly decreased due to the rapid conversion of the dislocation loops into network dislocations. In addition, subgrains were observed in the Fe-Cr alloys after irradiation. The underlying reason behind the formation of subgrains is discussed in detail.

The Prognostic Value of Baseline Distant Metastasis in Icotinib-Treated Patients with EGFR-Mutated Stage IV Non-Small Cell Lung Cancer.

PURPOSE: Several studies have revealed the prognostic value distant metastasis in non-small-cell lung cancer (NSCLC) patients receiving first-line epidermal growth factor receptor (EGFR) inhibitors. However, the question of whether the specific metastatic site could predict survival outcomes remain elusive. This study evaluated the prognostic value of specific metastatic site at diagnosis in first-line icotinib-treated patients with EGFR-mutated advanced NSCLC. METHODS: A total of 216 patients with EGFR-mutated stage IV NSCLC who received first-line icotinib treatment were retrospectively enrolled. The associations between the presence of distant metastasis to certain organs at diagnosis and survival outcomes were analyzed. PATIENTS AND METHODS: The presence of distant metastases was not associated with progression-free survival. Patients with liver metastasis showed a significantly shorter OS than those without liver metastasis (14.6m vs 33.0m, p=0.024). Patients with brain metastasis showed a marginally shorter OS than those without brain metastasis (26.5m vs 33.8m, p=0.051). Patients with lung metastasis showed a significantly longer OS than those without lung metastasis (36.0m vs 28.6m, p=0.038). Multivariable Cox regression analysis showed the presence of liver metastasis (HR [hazard ratio]: 2.265, 95% CI [confidence interval]: 1.239-4.139, p=0.008) and brain metastasis (HR: 1.493, 95% CI: 1.012-2.202, p=0.043) were independent predictors for unfavorable OS, while lung metastasis (HR: 0.669, 95% CI: 0.460-0.971, p=0.034) was an independent predictor for favorable OS. CONCLUSION: The presence of liver and brain metastasis predicted unfavorable OS, while the presence of lung metastasis predicted favorable OS in first-line icotinib-treated patients with EGFR-mutated stage IV NSCLC.

Insurance disparity in cardiovascular mortality among non-elderly cancer survivors.

BACKGROUND: Insurance status plays a vital role in cancer diagnosis, treatments and survival. Cancer patients have higher cardiovascular disease (CVD) mortality than the general population. METHODS: The Surveillance, Epidemiology and End Results (SEER) program 2007-2016 was used to estimate the CVD mortality among cancer patients aged 18 to 64 years at the time of diagnosis of an initial malignancy with the eight most prevalent cancers. Standardized mortality ratios (SMRs) were calculated for each insurance (Non-Medicaid vs Medicaid vs Uninsured) using coded cause of death from CVD with adjustment of age, race, and gender. The Fine-Grey Model was used to estimate adjusted Hazard Ratios (HR) of each insurance in CVD mortality. RESULTS: A total of 768,055 patients were included in the final analysis. CVD death in patients with Medicaid insurance remained higher than in those with Non-Medicaid insurance (HR = 1.71; 95%CI, 1.61-1.81; p < 0.001). Older age, male gender, and black race were all associated with increased CVD mortality in the multivariable model. Compared to the general population, patients with Medicaid had the highest SMRs of CVD mortality, regardless of year of cancer diagnosis, follow-up time, cancer site, and race. Non-Medicaid insured patients had similar CVD mortality to the general population after 2 years out from their cancer diagnosis. CONCLUSION: Cancer patients with Non-Medicaid insurance have significantly lower CVD mortality than those with no insurance or Medicaid. The insurance disparity remained significant regardless of type of CVD, cancer site, year of diagnosis and follow-up time.

Patients With Acute Ischemic Stroke Who Receive Brain Magnetic Resonance Imaging Demonstrate Favorable In-Hospital Outcomes.

Background Use of inpatient brain magnetic resonance imaging (MRI) in patients with acute ischemic stroke is highly institution dependent and has been associated with increased length and cost of hospital stay. We examined whether inpatient brain MRI in patients with acute ischemic stroke is associated with improved clinical outcomes to justify its resource requirements. Methods and Results The National Inpatient Sample database was queried retrospectively to find 94 003 patients who were admitted for acute ischemic stroke and then received inpatient brain MRI between 2012 and 2014. Multivariable regression analysis was performed with respect to a control group to assess for differences in the rates of inpatient mortality and complications, as well as the length and cost of hospital stay based on brain MRI use. Inpatient brain MRI was independently associated with lower rates of inpatient mortality (1.67% versus 3.09%; adjusted odds ratio [OR], 0.60; 95% CI, 0.53-0.68; P<0.001), gastrostomy (2.28% versus 2.89%; adjusted OR, 0.82; 95% CI, 0.73-0.93; P<0.001), and mechanical ventilation (1.97% versus 2.82%; adjusted OR, 0.68; 95% CI, 0.60-0.77; P<0.001). Brain MRI was independently associated with ≈0.32 days (8%) and $1131 (11%) increase in the total length (P<0.001) and cost (P<0.001) of hospital stay, respectively. Conclusions Inpatient brain MRI in patients with acute ischemic stroke is associated with substantial decrease in the rates of inpatient mortality and complications, at the expense of marginally increased length and cost of hospitalization.

Hemodynamic monitoring in patients with venoarterial extracorporeal membrane oxygenation.

Veno-arterial extracorporeal membrane oxygenation (VA-ECMO) is an effective mechanical circulatory support modality that rapidly restores systemic perfusion for circulatory failure in patients. Given the huge increase in VA-ECMO use, its optimal management depends on continuous and discrete hemodynamic monitoring. This article provides an overview of VA-ECMO pathophysiology, and the current state of the art in hemodynamic monitoring in patients with VA-ECMO.

Laser with 10-13 short-term instability for compact optically pumped cesium beam atomic clock.

We realize a high-stability laser by modulation transfer spectroscopy and apply it to implement a high-performance compact optically pumped cesium beam atomic clock. Evaluated by the optical heterodyne method with two identical frequency-stabilized lasers, the frequency instability of the 852 nm laser directly referenced on thermal atoms is 2.6×10-13 at the averaging time of 5 s. Factors degrading the frequency stability of the laser are analyzed, and we will further control it to reduce the frequency noise of the laser. By comparing with a Hydrogen maser, the measured Allan deviation of the high-stability-laser-based cesium beam atomic clock is 2×10-12/τ, dropping to 1×10-14 in less than half a day of averaging time. To our knowledge, the Allan deviation of our cesium clock is better than that of any reported compact cesium beam atomic clocks at the averaging time of half-day. The high-performance atomic clock can promote the fields in metrology and timekeeping, and the high-stability laser additionally possesses great potential to be a compact optical frequency standard.

Effects of Silicon Content and Tempering Temperature on the Microstructural Evolution and Mechanical Properties of HT-9 Steels.

Two kinds of experimental ferritic/martensitic steels (HT-9) with different Si contents were designed for the fourth-generation advanced nuclear reactor cladding material. The effects of Si content and tempering temperature on microstructural evolution and mechanical properties of these HT-9 steel were studied. The microstructure of experimental steels after quenching and tempering were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), and transmission electron microscopy (TEM); the mechanical properties were investigated by means of tensile test, Charpy impact test, and hardness test. The microscopic mechanism of how the microstructural evolution influences mechanical properties was also discussed. Both XRD and TEM results showed that no residual austenite was detected after heat treatment. The results of mechanical tests showed that the yield strength, tensile strength, and plasticity of the experimental steels with 0.42% (% in mass) Si are higher than that with 0.19% Si, whereas hardness and toughness did not change much; when tempered at 760 °C, the strength and hardness of the experimental steels decreased slightly compared with those tempered at 710 °C, whereas plasticity and toughness increased. Further analysis showed that after quenching at 1050 °C for 1 h and tempering at 760 °C for 1.5 h, the comprehensive mechanical properties of the 0.42% Si experimental steel are the best compared with other experimental steels.

High-resolution performance of triptycene functionalized with polycaprolactones for gas chromatography.

Developing highly selective stationary phases is essential to address the issues for separation of analytes with similar properties and various components in complex samples. Herein, we report a new triptycene-based material functionalized with polycaprolactone moieties (TP-PCL) as the stationary phase with high-resolution performance for gas chromatography (GC). The TP-PCL capillary column exhibited column efficiency of 5555 plates/m and moderate polarity. On the column, dozens of mixtures of positional and structural isomers can be well resolved, involving benzene derivatives with varying substituents (alkyl, halo, nitro, hydroxyl, amino), naphthalene derivatives, alkanes and alcohols. It exhibits advantageous performance for high resolution of the critical pairs of alkylbenzenes, phenols, anilines and alkanes over the PCL column and commercial DB-35 MS column with similar polarity. Moreover, the TP-PCL column showed excellent separation repeatability and reproducibility with RSD values of 0.02%-0.07% for run-to-run (n = 4), 0.11%-0.18% for day-to-day (n = 4) and 2.1%-4.7% for column-to-column (n = 4). In addition, it exhibited distinctly enhanced thermal stability in contrast to the PCL column. Its application to analysis of the essential oil from Artemisiae argyi proves its good potential for practical use.