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Background Peripheral artery disease (PAD) is a common and serious cardiovascular disease, which is prone to complications of limb ischemia and adverse cardiovascular events. There is a gender difference in the prevalence of PAD, which has been relatively poorly studied. A full understanding of gender differences in prevalence of PAD in China is essential for public health policy development. Objective To analyze the gender differences in the prevalence of PAD in China and their causes, providing a theoretical basis for targeted screening and preventive measures. Methods The number of PAD cases, prevalence, age-standardized prevalence, attributable risk factors for disease burden, and corresponding 95% uncertainty intervals (UI) were extracted from the 2019 Global Burden of Disease (GBD) database for males and females in China and females in Japan, Korea, India and globally. R language was used to analyze the data and visualize the analysis of this study. Joinpoint software was used to analyze the trend of PAD prevalence in males and females in China over time from 1990 to 2019, and the annual percentage change (APC) and average annual percentage change (AAPC) of PAD prevalence and their 95% confidence intervals (CI) were calculated. A Bayesian age-period-cohort (BAPC) model was used to predict the number and prevalence of PAD in 2020—2035. Results The estimated prevalence of PAD in China in 2019 was 71.74×100 000 for males and 213.15×100 000 for females. Compared with 1990, the number of PAD cases in 2019 increased by 154.22% in males and 181.27% in females. In 2019, the number of cases and prevalence of PAD among males in Japan, Korea, India and globally were all higher than those in 1990, but the age-standardized prevalence was lower. In 1990, the age-standardized prevalence of PAD among women in China was 57.80% and 76.35% of those in Japan and Korea, 1.10 times and 1.33 times of those in Japan and Korea in 2019. The prevalence of PAD in Chinese men was 462.40/100 000 in 1990 and 989.79/100 000 in 2019, with an increase of 114.05%, and showed an upward trend during 1990 to 2019. The prevalence of PAD in Chinese women was 1 321.44 per 100 000 in 1990 and 3 055.85/100 000 in 2019, with an increase of 131.25%, and showed an upward trend from 1990 to 2019. The prevalence of PAD in Chinese women was 3.09 times higher than that of men in 2019. The age-standardized prevalence of PAD in Chinese males was 731.02/100 000 in 1990 and 744.96/100 000 in 2019, with an increase of 1.91%, showed an increasing trend from 1990 to 1993 and from 1993 to 2005, and a decreasing trend from 2005 to 2019. The age-standardized prevalence of PAD in Chinese women was 1 839.43/100 000 in 1990 and 2 022.13/100 000 in 2019, with an increase of 9.93%, showing an increasing trend from 1990 to 2005 (P0.05). In 2019, the age-standardized prevalence of PAD in Chinese women was 2.71 times of men. BAPC model predicts that the number of PAD cases will reach 101.30×100, 000 in Chinese men and 319.24×100 000 in Chinese women by 2035. In 2035, the number of Chinese women with PAD will increase by 49.77% compared with 2019. In terms of age, the largest number of Chinese women aged 65-69 with PAD in 2019 will be 35.15×100 000, and the largest number of women aged 70-74 with PAD in 2035 will be 55.89×100 000. In 2035, the number of Chinese women aged 40 to 44, 45 to 49, 50 to 54 and 55 to 59 with PAD will be lower than that in 2019, and the number of Chinese women aged 60 to 64, 65 to 69, 70 to 74, 75 to 79, 80 to 84, 85 to 89, 90 to 94 and≥95 with PAD will be higher than that in 2019. In 2035, the age-standardized prevalence of PAD in Chinese men and women will be 712.09/100 000 and 1 945.97/100 000, respectively, decreasing by 4.41% and 3.77% compared with 2019. By age, the prevalence of PAD in Chinese women in 2035 will increase with age, and the prevalence of PAD in all age groups will be decreased compared with 2019 except for those aged≥95 years. The disease burden of PAD in China in 2019 can be attributed to six risk factors, including hypertension, smoking, diabetes, renal insufficiency, high-salt diet and lead exposure. The most important risk factor for men was smoking (44.32%), followed by hypertension (18.97%) and diabetes (16.11%). The most common risk factor for women was hypertension (32.31%), which was followed by diabetes (24.81%) and renal insufficiency (17.27%) . Conclusion The number of cases, prevalence and age-specific prevalence of PAD in Chinese women are significantly higher than those in men, and the age-standardized prevalence has already exceeded that of Japan and Korea. In the foreseeable future, the number of Chinese women suffering from PAD will further increase, and the number of elderly women suffering from PAD will increase more and more obviously. Therefore, more attention should be paid to the changes in gender and age, and gender differences in risk factors of PAD patients, and necessary screening and prevention measures should be taken.

The loss of boron (B) in the rack plate steel during the electroslag remelting process has a significant impact on its mechanical properties. Therefore, it is necessary to design appropriate slags to suppress the loss of B. CaF2–CaO–Al2O3 phase diagram was calculated to determine the basic slag. The influence of MgO and B2O3 on the performance of the basic slag was studied to determine the optimal amount of MgO addition. The equilibrium reactions between rack plate steel and the 50.48 mass% CaF2–24.81 mass% CaO–24.71 mass% Al2O3–2 mass% MgO-y mass% B2O3 (y was 1–10) slag were studied to examine the variation in B content in the steel. Results indicate the presence of a temperature-qualified eutectic point in the CaF2–CaO–Al2O3 phase diagram. With an increase in MgO content in the slag, the melting temperature of the basic slag initially decreases and then increases, while the electrical conductivity decreases. On the other hand, B2O3 reduces the melting point of the slag and increases the equilibrium B content in the steel. The 50.48 mass% CaF2–24.81 mass% CaO–24.71 mass% Al2O3–2 mass% MgO-y mass% B2O3 (y was 5–7) slag can achieve the target range of B content in the steel, and its viscosity meets the requirements of electric slag remelting.

In recent years, some people with high intelligence and high quality have violated the law and even committed crimes, which has ruined their bright future. It is really sad. A school is a place where teenagers learn skills and improve their quality. It should be a pure land. The frequent occurrence of juvenile students’ crimes seriously affects the normal teaching order and endangers the safety of students’ lives and property. With the rapid development of support vector machines (Abbreviation: SVM), it has also become one of the main data fusion technologies. SVM is a creative machine learning method based on statistical learning theory. It is a learning method specialized in finite sample prediction. This paper studies the psychological characteristics of students’ crimes based on the SVM algorithm. From the aspect of proportion, the result of the SVM algorithm is ideal, and the proportion of the training set is up to 33.35%. The above algorithm has good expansibility for such sample data, but when the parameters are not appropriate, the proportion is only more than 20.12%, which once again explains the importance of the SVM algorithm. Only through the SVM algorithm to improve the efforts of the whole society, can we put an end to the generation of criminal psychology of higher vocational students from the source and cultivate more high-quality talents for the country.

Leukocyte immunoglobulin (Ig)-like receptor Bs (LILRBs), a family of type I transmembrane glycoproteins, are known to inhibit immune activation. Here, we comprehensively evaluated the molecular, prognostic, and immunological characteristics of LILRB members in a broad spectrum of cancer types, focusing on their roles in acute myeloid leukemia (AML). We showed that LILRBs were significantly dysregulated in a number of cancers and were associated with immune-inhibitory phenotypes. Clinically, high expression of LILRB1-LILRB4 predicted poor survival in six independent AML cohorts. Genetically, LILRB1 was associated with more mutational events than other LILRB members, and multiple genes involved in immune activation were deleted in LILRB1high patients. Epigenetically, LILRB4 was significantly hypomethylated and marked by MLL-associated histone modifications in AML. Immunologically, LILRBs were positively associated with monocytic cells, including M2 macrophages, but were negatively associated with tumor-suppressive CD8 T cells. Importantly, patients with higher LILRB expression generally showed a better response to immune checkpoint blockade (ICB) in five independent immunotherapy cohorts. Our findings reveal critical immunological and clinical implications of LILRBs in AML and indicate that LILRBs may represent promising targets for immunotherapy of AML.

The influence of chromium‐bearing filler sand on the transformation of inclusions in high‐Mn and high‐Al steel under various reaction times and Mn content levels is studied, and the mechanism of filler sand intrusion into the steel matrix is analyzed. It is demonstrated that an inclusion containing Cr2O3 is discovered. The evolution pathway of oxide inclusions is identified as Al2O3–MnO → Al2O3–MnO–SiO2 → Al2O3–MnO–SiO2–Cr2O3(Cr2O3 + MnO–SiO2) → Al2O3–MnO–Cr2O3–MgO·Al2O3. It is noteworthy that Cr2O3 inclusions tend to diffuse from the outside inward, but the internal content remains almost unchanged, which is due to the strong diffusion hindrance of SiO2. The formation of a liquid phase in the filler sand is a necessary condition for its infiltration into the steel matrix. The critical liquid‐phase content that results in the formation of Cr2O3 inclusions is 42%, which contains 5–8% of Cr2O3. The formation of pore channels provides favorable conditions for sand penetration, with the maximum penetration depth reaching up to 29 mm. Large sand inclusion particles reach millimeter scale in size and are distributed quite randomly. Chemical reactions at the steel/sand interface can lead to an increase in the total oxygen (T.O) content in the steel. The reaction time has little effect on the T.O content, while the Mn content in the steel has a significant impact, with an increase of up to 41 ppm. During the smelting stage, the filler sand can enter the molten steel, thereby affecting the quality of the product. [ABSTRACT FROM AUTHOR]

BackgroundPapillary thyroid carcinoma (PTC) concurrent with Hashimoto’s thyroiditis (HT) was associated with a better clinical prognosis. This study aimed to investigate a potential mRNA gene that affects the development of PTC, which helps PTC concurrent with HT patients have a better prognosis.Material/MethodsPTC data were obtained from The Cancer Genome Atlas (TCGA) database. And the validation data of tissue specimens were collected from Guangzhou First People’s Hospital. The thyroid tissue sections were hybridized with deleted in malignant brain tumor 1 (DMBT1) probes by situ hybridization. Survival rates were analyzed using Kaplan-Meier curves, and the log-rank test was used to compare group survival rates. Prognosis clinicopathological factors were analyzed by Cox regression. Gene Ontology (GO) and Kyoto Gene and Genomic Encyclopedia (KEGG) pathway enrichment analyses were performed using single-sample gene set enrichment analysis (ssGSEA). Finally, the correlation of deletion in DMBT1 expression with overall immune status, tumor purity, and human leukocyte antigen (HLA) gene expression profile was analyzed.ResultsHT was significantly associated with sex, tumor foci, extrathyroidal extension (ETE), residual tumor, and tumor stage (T stage). Moreover, PTC concurrent with HT had a lower risk of recurrence versus non-HT groups. A total of 136 differentially expressed mRNAs (DEMs) were identified between HT and non-HT groups. Among them, the expression level of DMBT1 in HT groups was statistically higher than that in non-HT groups. A significant association with ETE and recurrence was revealed in the high expression and the low expression of DMBT1. Furthermore, DMBT1 was an independent predictor of survival. The overall immune activity of high expression of DMBT1 was higher than that of the low-expression group.ConclusionsThe PTC patients with HT had better behavior features and prognosis than those with simple PTC. DMBT1 in PTC-HT patients was a potential possible factor that inhibits tumors. High expression of DMBT1 may improve PTC prognosis by immune-related pathways.

Background Accumulating studies have been made to understand the association between CXC chemokine ligand-12 (CXCL12)/CXC chemokine receptor 4 (CXCR4) and acute myeloid leukemia (AML). However, large-scale data analysis of potential relationship between CXCL12 and AML remains insufficient. Methods We collected abundant CXCL12 expression data and AML samples from several publicly available datasets. The CIBERSORT algorithm was used to quantify immune cell fractions and the online website of STRING was utilized for gene ontology (GO) enrichment and Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis. The statistical analysis and graphical work were mainly performed via the R software. Results CXCL12 expression was extremely down-regulated in AML. Clinically, low CXCL12 expression was correlated with higher white blood cells (WBCs) (P < 0.0001), more blasts in bone marrow (BM) (P < 0.001) and peripheral blood (PB) (P < 0.0001), FLT3-internal tandem duplications (FLT3-ITD) (P = 0.010) and NPM1 mutations (P = 0.015). More importantly, reduced CXCL12 expression predicted worse overall survival (OS) and event-free survival (EFS) in all AML, non-M3-AML, and cytogenetically normal (CN)-AML patients in three independent cohorts. As for immune cell infiltration, high CXCL12 expressed groups tended to harbor more memory B cells and plasma cells infiltration while low CXCL12 expressed groups exhibited more eosinophils infiltration. GO enrichment and KEGG pathways analysis revealed the potential biological progress the gene participating in. Conclusions CXCL12 is significantly down-regulated in AML and low CXCL12 expression is an independent and poor predictor of AML prognosis. CXCL12 expression level correlates with clinical and immune characteristics of AML, which could provide potential assistance for treatment. Prospective studies are needed to further validate the impact of CXCL12 expression before routine clinical application in AML.

Developing novel filler sands has garnered significant interest in improving the ladle's free‐opening rate and enhancing the cleanliness of high‐Mn and high‐Al steel. Laboratory studies explore the effect of adding Cr2O3 powder on the sintering behavior of chromite‐based filler sands. Furthermore, interfacial phenomena are examined between the sands and the steel grades, varying in Mn contents. The results demonstrate that adding Cr2O3 power plays a role in inhibiting the liquid phase formation in the sand. With a 16% addition, the steel (Mn mass% = 30) reacts with the sand, leading to the shape of a spinel phase, specifically (Mn, Fe, Mg)O·(Al, Cr)2O3, which facilitates the separation of the liquid phase. The reduction of FeO to Fe by Mn, Al, and C in steel, especially Al, is hindered by adding Cr2O3, resulting in a suitable sintering degree that ultimately benefits ladle free‐opening. SiO2 is crucial for forming the liquid phase during the sintering process. The SiO2 content of the sand should be about 20% to achieve optimal sintering effects. Chromite sand for casting is not suitable for the steels. The mixed sand presented in the current study demonstrates potential as a suitable filler sand for the steel (20 ≤ Mn mass% ≤ 30). [ABSTRACT FROM AUTHOR]

Simple Summary: The prevalence of certain cancers is high in the diabetic population. Dipeptidyl peptidase (DPP)-4, a therapeutic target for type 2 diabetes mellitus, is also involved in autophagic flux and cancer biology. In this paper, we reported that DPP-4 inhibition promotes breast cancer cell survival via induction of autophagy by the C-X-C motif chemokine 12/C-X-C receptor 4/mammalian target of rapamycin/hypoxia-inducible factor-1α axis. Metformin counteracts such an undesirable influence of DPP-4 inhibition on cancer biology. Our findings suggest that DPP-4 inhibitor, one of the most prescribed anti-diabetic drugs, could harm patients with certain cancers. The combination with metformin use could provide some clues to the use of DPP-4 inhibitors via the modulation of cancer autophagy-dependent survival signaling. Autophagy plays a complex role in breast cancer cell survival, metastasis, and chemotherapeutic resistance. Dipeptidyl peptidase (DPP)-4, a therapeutic target for type 2 diabetes mellitus, is also involved in autophagic flux. The potential influence of DPP-4 suppression on cancer biology remains unknown. Here, we report that DPP-4 deficiency promotes breast cancer cell survival via the induction of autophagy by the C-X-C motif chemokine 12 (CXCL12)/C-X-C receptor 4 (CXCR4)/mammalian target of rapamycin (mTOR)/hypoxia inducible factor (HIF)-1α axis. DPP-4 knockdown and DPP-4 inhibitor KR62436 (KR) treatment both increased the levels of LC3II and HIF-1α in cultured human breast and mouse mammary cancer cells. The KR-induced autophagic phenotype in cancer cells was inhibited by treatment with the CXCR4 inhibitor AMD3100 and rapamycin. HIF-1α knockdown also suppressed breast cancer autophagy induced by KR. The autophagy inhibitor 3-methyladenine significantly blocked the KR-mediated suppression of cleaved caspase-3 levels and apoptosis in breast cancer cell lines. Finally, we found that the metformin-induced apoptosis of DPP-4-deficient 4T1 mammary cancer cells was associated with the suppression of autophagy. Our findings identify a novel role for DPP-4 inhibition in the promotion of breast cancer survival by inducing CXCL12/CXCR4/mTOR/HIF-1α axis-dependent autophagy. Metformin is a potential drug that counteracts the breast cancer cell survival system. [ABSTRACT FROM AUTHOR]

BACKGROUND: Velvetleaf (Abutilon theophrasti Medik.), primarily a cropland weed, exerts adverse impacts on the productivity of various crops, including soybean (Glycine max L.), wheat (Triticum aestivum L.), and maize (Zea mays L.), by hindering their vegetative growth. However, the interference mechanism of velvetleaf on the three crops remains unclear. RESULTS: The inhibitory effect of velvetleaf water extract on the germination and growth of soybean, wheat, and maize was determined in pot experiments and field trials. Four phenolic acids were identified as allelochemicals: protocatechuic acid (PA), gallic acid (GA), chlorogenic acid (CHA), and vanillic acid (VA). These allelochemicals were detected in different parts (leaves, roots, and stems) of velvetleaf, and in the rhizosphere soil of tested crops over the range of 1.19–556.23 μm kg−1. These allelochemicals were administered in approximate concentrations as in velvetleaf roots and rhizosphere soil, and their effects varied with crop species and velvetleaf parts. The allelochemicals generally had low‐dose stimulation and high‐dose inhibition effects on the growth of soybean, wheat, and maize. Furthermore, the biomass distribution of these crops was affected by allelochemicals in the soil. In field trials, the allelochemicals significantly (P < 0.05) inhibited the growth of all tested crops over the whole growth period, and PA showed a significant (P < 0.05) inhibitory effect on the yield of soybean, wheat, and maize. CONCLUSION: GA, PA, CHA, and VA in velvetleaf aqueous extracts were identified as allelochemicals that play an inhibitory role on three crops. © 2022 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

Head-on collisions of magnetoacoustic solitary waves (MASWs) are studied in magnetized pair ion-electron plasma. The extended Poincare-Lighthill-Kuo perturbation method is used to derive the Korteweg--de Vries equations for MASWs in this three-component plasma. The effects of the magnetic field intensity [B.sub.0], the ratio of negative ions to positive ions number density S, and the plasma number density on the phase shift are investigated. It is found that these parameters can significantly influence the phase shifts of colliding MASWs. The present investigation should be useful for understanding the propagation and interaction between two MASWs that may occur in pair ion plasmas with electron impurities. PACS Nos.: 52.25.Xz, 52.35.Sb, 52.35.Mw. Nous etudions les collisions frontales d'ondes solitaires magneto-acoustiques (MASW) dans un plasma ion-electron pair magnetise. Nous utilisons la methode de perturbations de Poincare-Lighthill-Kuo pour obtenir les equations de Korteweg- -de Vries (KdV) pour des MASW dans ce plasma a trois composantes. Nous analysons les effets sur le dephasage dus a la densite de champ magnetique [B.sub.0], au rapport S de la densite d'ions negatifs sur les ions positifs et a la densite du plasma. La reponse est que ces parametres peuvent affecter significativement le dephasage dans des collisions de MASW. Cette etude devrait etre utile pour mieux comprendre la propagation et l'interaction entre deux MASW qui peuvent apparaitre dans un plasma ionique avec des impuretes electroniques. [Traduit par la Redaction], 1. Introduction In recent years, pair ion (PI) plasmas consisting of only positive and negative ions of equal mass have received considerable attention. PI plasmas represent a new state of [...]

The root extracts and root exudates from the Taxus chinensis var. mairei had significant promote effects on growth of Camptoteca acuminata seedlings. Four taxane chemicals, cephalomannine, 10-deacetylbacatin III, paclitaxel and 7-Epi-10-deacetyl-paclitaxel, were isolated from T. chinensis var. mairei root extracts and their structures were identified by spectroscopic analysis. The chemicals were detected in T. chinensis var. mairei root exudates, rhizosphere soils, and their concentrations ranged from 0.01 to 5.90 μg/g. At an approximate concentration determined in T. chinensis var. mairei root exudates, all four chemicals significantly promoted the growth of C. acuminata seedlings. Therefore, four chemicals from T. chinensis var. mairei root exudates may act as allelochemicals accelerating growth of C. acuminata seedling. There were significant relationships between growth of C. acuminata seedlings, soil properties, enzyme activities and microbial community under allelochemicals' application. The results provide a reference for in-depth understanding of C. acuminata and T. chinensis var. mairei interactions. [ABSTRACT FROM AUTHOR]

Wild Camptotheca acuminata Decne (C. acuminata) resources are becoming endangered and face poor growth. Preliminary investigation results found that the growth of C. acuminata in an artificial mixed forest of Taxus chinensis var. mairei (Lemee et Levl.), Cheng et L. K. Fu (T. chinensis var. mairei) and C. acuminata was significantly higher than that in pure forests. Understanding the reasons for the above differences can help create a mixed forest of T. chinensis var. mairei and C. acuminata to solve the problem of depleting C. acuminata resources. In this study, the growth and soil indexes under two different modes (C. acuminata/T. chinensis var. mairei interplanted and monocultured C. acuminata seedlings) were compared. The results showed that plant height, basal diameter, photosynthesis rate and chlorophyll content of C. acuminata under the interplanting mode were higher than those under monoculture. The growth rates of plant height and basal diameter that were calculated from interplanted specimens increased by 25% and 40%, respectively, compared with those from specimens that were monocultured. Photosynthetic rates from different light intensities under interplanting were higher than those in seedlings under monoculture. The contents of chlorophylls a and b and total chlorophyll under interplanting were 1.50, 1.59, and 1.47 times higher than those under monoculture, respectively. The numbers of bacteria and fungi in the interplanted culture were higher than those in the monoculture. Furthermore, the differences in microbial diversity under different planting modes were analyzed via the amplicon sequencing method. Soil enzyme activities increased under interplanting compared with that in the monoculture. Taxane allelochemicals were detected in the range of 0.01–0.67 μg/g in the interplanting mode from April to September. T. chinensis var. mairei may increase the establishment and productivity of C. acuminata seedlings under interplanting mode through improvements in enzyme activity, changes in microorganism population structure, and release of allelochemicals. [ABSTRACT FROM AUTHOR]

To observe the clinical effect of combined acupuncture and kinesiotherapy on upper cross syndrome (UCS) by a parallel randomized clinical trial. A total of 45 patients with UCS were recruited from the outpatients of Acupuncture-Moxibustion, Tuina and Rehabilitation Department of the First Affiliated Hospital of Hunan University of Chinese Medicine, the students of Hunan University of Chinese Medicine and the patients from the nearby communities in accordance with the inclusion criteria. Using the random number table method, they were divided into a combined treatment group (acupuncture plus kinesiotherapy, 23 cases) and a simple kinesiotherapy group (22 patients). Treatment for 4 weeks was one course, and two consecutive courses were required. The visual analog scale (VAS) score, the score of the assessment scale for cervical spondylosis, the value of surface electromyography (root mean square, RMS), and the cervical curvature value were used in the evaluation. The allocation scheme was concealed from the outcome assessors. The data from 23 cases of the combined treatment group and 22 cases of the simple kinesiotherapy group were analyzed. Before treatment, the differences were not statistically significant in the general conditions, VAS score, assessment score of cervical spondylosis, cervical curvature value, and RMS in UCS patients between the two groups (all P > 0.05). After treatment, the VAS score was reduced compared with that before treatment in both groups (all P < 0.05). In two courses of treatment, the VAS score decreased as compared with that in one course of treatment in both groups (both P < 0.05), and the VAS score in the combined treatment group decreased more obviously after each course of treatment (both P < 0.05). The RMS decreased compared with that before treatment in each group (both P < 0.05), and the decrease in the combined treatment group was more obvious (P < 0.05). After treatment of each course, the assessment score was all increased as compared with that before treatment in two groups (all P < 0.05). In two courses of treatment, the assessment score was increased as compared with that in one course of treatment in both groups (both P < 0.05), and the score in the combined treatment group was increased more obviously in the two courses of treatment (P < 0.05). Regarding either the intra-group comparison or the inter-group comparison before and after treatment, the differences were not statistically significant (all P > 0.05), suggesting no obvious improvement of cervical curvature in the two courses of treatment in patients with UCS. However, cervical curvature tended to improve in the combined treatment group. The total effective rate was significantly different between the two groups (P < 0.05), indicating that the total effective rate in the combined treatment group was better than that in the simple kinesiotherapy group.No any adverse reactions occurred. Combined treatment with acupuncture, kinesiotherapy, and kinesiotherapy alleviated pain, relieved the symptoms and physical signs, and improved the daily movement of the patients. However, the combined treatment of acupuncture and kinesiotherapy had a much better effect on UCS. [ABSTRACT FROM AUTHOR]

The velvetleaf (Abutilon theophrasti Medik.) is a strong and competitive weed in fields that inhibits the growth of crops. Reports have suggested that allelopathy is one of the reasons for this inhibition; however, the mechanism of this allelopathy remains unclear. In this study, velvetleaf powder/extracts were shown to inhibit seed germination, growth and yield in maize, wheat and soybean through petri dish, pot and field control experiments. We observed a concentration-dependent inhibition of the seed germination rate for all three crops. The root tip structure changed significantly and the embryo even died when irrigated with a high concentration of the extract (10 mg·mL−1). After adding velvetleaf powder, the malondialdehyde (MDA) content in crop seedlings was dose-dependent, and the superoxide dismutase (SOD) activity of maize, wheat and soybean showed the maximum values under treatment with 1.25, 5 and 5 mg·cm−3, respectively. The activity of peroxidase (POD) showed the highest value under the 5 mg·cm−3 treatment in maize and wheat seedlings and under 10 mg·cm−3 treatment in soybean seedlings. However, sugar, protein content and root activity in all three crops was the lowest under the 10 mg·cm−3 treatment. Therefore, velvetleaf may decrease the productivity of three crops by changing the antioxidant enzyme activities, root system activities and root tip structures. [ABSTRACT FROM AUTHOR]

A simple Pd/Cu-catalyzed borylation of allenylic carbonates with B2Pin2 was developed using a cheap P(OEt)3 ligand. Under mild neutral conditions, 2-boryl 1,3-butadienes were obtained selectively in moderate to high yields. Furthermore, the use of different diboron reagents was also feasible in the reaction. [ABSTRACT FROM AUTHOR]