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Abstract Polyimide (PI) dielectric nanocomposites containing functional nanofillers based on layered structure (single-layer: BT@[Al.sub.2][O.sub.3]@PI, double-layer: PI/BT@[Al.sub.2][O.sub.3]@PI, three-layer: PI/BT@[Al.sub.2][O.sub.3]@PI/PI) were designed and prepared by using PI as matrix, barium titanate (BT)@alumina [...]

Chenpi, or dried tangerine peel, is a traditional Chinese ingredient valued in medicine and edible for its digestive and respiratory benefits. The geographical origin of Chenpi is important, as it can impact its quality, active compounds and market value. This study develops a strategy to distinguish Chenpi samples on its origin. Thirty-nine samples from eight regions in Xinhui district (Guangdong, China) are analyzed by gas chromatography (GC) and mid-infrared (MIR) technique. Four machine learning methods are employed to establish discrimination models based on GC and MIR data, with two mid-level data fusion strategies to combine the data. The results show that data fusion significantly improves Chenpi origin discrimination. The K-nearest neighbors and artificial neural network models, using modified mid-level data fusion, provide the best performance, misclassified only one sample. Machine learning in combination with modified mid-level data fusion strategy provides effective classification of Chenpi samples from different geographical origins. [ABSTRACT FROM AUTHOR]

The present study aims to improve the mechanical, thermal and dielectric properties of polyetherimide (PEI) nanocomposite via simplified method, involving the creation of a nanocomposite using PEI incorporated with exfoliated‐chemical functionalization induced hexagonal boron nitride nanosheets (BNNS). XRD, FTIR and Raman elucidated the chemical structure of functionalized BNNS and indicated the success preparation of functionalized BNNS. Functionalization effectively improved the compatibility of nanocomposites and contributed to the property improvements. Morphological analysis unveiled a compact and dense microstructure within the nanocomposites in correlation with functionalized BNNS. Broad band dielectric spectroscopy revealed excellent dielectric properties of produced PEI nanocomposite. DMA testing verified a noteworthy enhancement in both Tg and storage modulus upon incorporating of BNNS. In summary, this comprehensive investigation highlights the impact of functionalized BNNS on mechanical, thermal and dielectric properties of developed PEI dielectric nanocomposite and is expected to expand the application of PEI in the field of high‐temperature energy storage. Highlights: Polyetherimide (PEI) was used as polymer matrix and boron nitride derivatives as dielectric fillers to prepare PEI dielectric nanocomposite.Due to the influences of dielectric properties by interface polarization effect and the local distribution of electric field of the fillers in PEI matrix, the dielectric constant, breakdown strength and energy storage density of PEI nanocomposites were obviously improved compared with pure PEI.The effects of interfacial interactions between PBNNS and PEI contributes to the uniform dispersion and comprehensive property improvements of PEI dielectric nanocomposites.This work presents a systematic investigation into the fabrication of PEI/BNNS nanocomposite using a one‐step solution blending method, inspiring the research and development of PEI in the energy storage applications areas in the future. [ABSTRACT FROM AUTHOR]

Background: Dietary iron intake and serum ferritin in relation to severe headache or migraine remain largely unknown. Therefore, we investigated the associations between dietary iron intake and serum ferritin with severe headache or migraine among American adults.Methods: This cross-sectional study included 7,880 adults (≥20 years) from the National Health and Nutrition Examination Surveys (NHANES) of America from 1999 to 2004. We performed multivariable logistic regression and restricted cubic spline (RCS) regression to assess the association of dietary iron and serum ferritin with severe headache or migraine.Results: Most women aged 20–50 years consumed less dietary iron than their recommended dietary allowances. Dietary iron intake was inversely associated with severe headache or migraine in women aged 20–50 years. For women over 50 years, serum ferritin was negatively associated with severe headache or migraine. For men, there was no significant relationship between dietary iron and serum ferritin, and severe headache or migraine.Conclusions: Dietary iron intake has different effects on migraine in women of different ages, and this different effect may be due to age-related menstrual changes. Women aged 20–50 years should have a higher awareness of RDA and increase their dietary iron intake if needed, which may play an important role in preventing severe headache or migraine. Higher serum ferritin levels in women aged 50 and above may have a protective effect against migraine.

Background: Migraine is a common neurological disorder and is affected by nutrients. Calcium and magnesium are essential minerals that play an important role in nerve function. So we investigated the association between dietary calcium and magnesium and migraine.Methods: We extracted 10,798 adults from the National Health and Nutrition Examination Surveys (NHANES) of America in 1999 to 2004. We classified patients who reported having severe headache or migraine as having possible migraine. Multivariable logistic regression and restricted cubic spline regression were conducted to determine the association between dietary calcium and magnesium and migraine.Results: We found that the adjusted ORs of the association between dietary calcium and magnesium and migraine for comparing the highest quintile intake with the lowest quintile intake were 0.77 (95% CI: 0.63–0.93, P = 0.008) and 0.69 (95% CI: 0.55–0.86, P = 0.001), respectively. For women, the adjusted ORs of dietary calcium and magnesium were 0.72 (95% CI: 0.56–0.93, P = 0.009) and 0.62 (95% CI: 0.47–0.83, P = 0.001), respectively. For men, the adjusted OR was 0.71 (95% CI: 0.52–0.97, P = 0.028) comparing the highest and the lowest quintile of calcium intake, but there was no statistically significant association between dietary magnesium intake and migraine. Joint analyses showed that the OR in the high-calcium and high-magnesium group was 0.74 (95% CI: 0.60–0.92, P = 0.006) compared with the low-calcium and low-magnesium group in women.Conclusions: High dietary intake of calcium and magnesium, independently or in combination, were inversely associated with migraine in women. For men, high dietary calcium was negatively related to migraine, but magnesium was not associated with migraine.

Abri Herba (Jigucao) and Abri mollis Herba (Maojigucao) are derived from dried plants of Abrus cantoniensis Hance (Leguminosae) and Abrus mollis without pods. Abri Herba is commonly used in Jigucao tablets; Abri mollis Herba is usually used in Jigucao capsules and FufangJigucao capsules. Surprising, there are few reports focused on the quantitative control of these mentioned Jigucao related pharmaceuticals. This research endeavour has harnessed the formidable power of cutting‐edge ACQUITY UPLC technology to formulate a groundbreaking methodology for the simultaneous quantification of 10 target compounds in Jigucao capsules, Jigucao tablets and FufangJigucao capsules. The primary aim is to bolster quality control and precise identification within the realm of these pharmaceutical products. Separation was performed on an ACQUITY UPLC HSS T3 Column (2.1 × 100 mm, 1.8 μm), gradient elution was performed with 0.1% formic acid in water and acetonitrile. A column temperature of 40°C acts as our guiding compass, and DAD detection scans the spectral landscape in the wavelength range of 210–400 nm. The concentrations of the 10 target components can be used to identify Jigucao tablets, Jigucao capsules and FufangJigucao capsules through the art of chemometrics. The results showed that the established method for determination of 10 target compounds was accurate and reliable with good linearity (r ≥.9948) and satisfactory recoveries (82.91%–108.6%). The identification of the three Jigucao related pharmaceuticals can be performed using chemometrics based on the 10 target compounds. Thus, our study not only showcases a pioneering analytical approach but also unveils a new dimension in the identification of these pharmaceutical treasures. [ABSTRACT FROM AUTHOR]

Penicillium oxalicum k10 isolated from soil revealed the hydrolyzing ability of shrimp chitin and antifungal activity against Sclerotinia sclerotiorum. The k10 chitinase was produced from a powder chitin-containing medium and purified by ammonium sulfate precipitation and column chromatography. The purified chitinase showed maximal activity toward colloidal chitin at pH 5 and 40 °C. The enzymatic activity was enhanced by potassium and zinc, and it was inhibited by silver, iron, and copper. The chitinase could convert colloidal chitin to N-acetylglucosamine (GlcNAc), (GlcNAc)2, and (GlcNAc)3, showing that this enzyme had endocleavage and exocleavage activities. In addition, the chitinase prevented the mycelial growth of the phytopathogenic fungi S. sclerotiorum and Mucor circinelloides. These results indicate that k10 is a potential candidate for producing chitinase that could be useful for generating chitooligosaccharides from chitinous waste and functions as a fungicide.

A new method for the analysis of four target flavonoids in two kinds of citrus samples by ultra-high performance supercritical fluid chromatography (UHPSFC) method was developed. Main variables affecting the UHPSFC separation were optimized, and under the optimized conditions the four target compounds (tangeretin, nobiletin, hesperetin and naringenin) can be separated within 10 min. The UHPSFC method allowed the determination of the four target compounds in the diluted stock solutions with limit of detection (LOD) ranging from 1.08 to 2.28 μg mL−1, and limit of quantification (LOQ) ranging from 1.45 to 4.52 μg mL−1, respectively. The coefficients of determination (R2) of the calibration curves were higher than 0.9950. The recoveries of the four target compounds at three different concentrations were in the range of 82.4–117.6%. The validation results demonstrated that the proposed method is simple, accurate, time-saving and environment friendly, and it is applicable to a variety of complex samples such as medicine-food dual purpose herbs and functional foods. [ABSTRACT FROM AUTHOR]

In order to explore effective strategies to fabricate main‐chain polybenzoxazine (PBZ) thermosetting resin for structural material applications, here, five PBZ with different molecular structures, that is, poly(Co‐ddm), poly(Co‐BPA‐ddm‐Co)main, poly(Ph‐BPA‐ddm‐Co)main, poly(Ph‐BPA‐ddm‐Ph)main and poly(Ph‐ddm) were designed, synthesized and compared by introducing unsaturated fatty chains through the Mannich reaction with cardanol. The structure and properties of five PBZ with different structure were systematically investigated by using Fourier transform infrared (FTIR), NMR, water absorption and mechanical tests. FTIR and NMR tests indicated that five PBZ with different molecular structures were successfully synthesized. The mechanical tests indicated that the impact strength of the double‐capped cardanol‐based main‐chain PBZ was 243% higher than that of the traditional PBZ. The water absorption of main‐chain PBZ was higher than that of diamine PBZ, and the water absorption of poly(Ph‐BPA‐ddm‐Co)main was the lowest in the main‐chain PBZ. Based on the experimental results, five PBZ amorphous cells with different structures were successfully established. It indicated that the main chain PBZ showed better thermomechanical properties than the traditional diamine PBZ due to high crosslinking conversion and hydrogen bond density. Moreover, the modulus and glass transition temperature of the main chain structure containing unsaturated fatty chains did not decrease significantly. [ABSTRACT FROM AUTHOR]

MicroRNA-181a (miR-181a) is upregulated in osteosarcoma, and its overexpression promotes the proliferation and inhibits the apoptosis of osteosarcoma cells. However, the mechanism of miR-181a as an oncogene remains to be fully elucidated in osteosarcoma. Cleavage factor (CF) Im25 links alternative polyadenylation to glioblastoma tumor suppression, however, its role in osteosarcoma has not been reported. In the present study, it was confirmed that the expression of miR-181a was upregulated in osteosarcoma, and that silencing miR-181a inhibited the proliferation and promoted the apoptosis of osteosarcoma cells. miRNAs are short non-coding RNAs, which regulate target mRNAs by binding predominantly to the 3'untranslated region (3'UTR), inducing either translational repression or degradation of the target. In the present study, target genes of miR-181a were screened using miRanda, which is a commonly used prediction algorithm. It was found that miR-181a targeted the 3'UTR of CFIm25 mRNA. Subsequent experiments confirmed that miR-181a downregulated the expression of CFIm25 in osteosarcoma cells. Finally, it was demonstrated that the CFIm25 protein was also downregulated in osteosarcoma tissues, and inhibited the proliferation and promoted the apoptosis of the cells. Elucidating the roles of miR-181a and CFIm25 in osteosarcoma not only assists in further understanding the pathogenesis and progression of this disease, but also offers novel targets for effective therapies. [ABSTRACT FROM AUTHOR]