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Pyracantha fortuneana (P. fortuneana), as a medicinal and edible plant resource, is rich in nutrients. In order to screen the high quality yeast used in Firebone fruit wine, 12 strains of yeast were isolated and purified from P. fortuneana fermentation broth by traditional pure culture method. They were identified by molecular biology as Pichia kudriavzevii (P. kudriavzevii) and Saccharomyces cerevisiae (S. cerevisiae), respectively. Strain HJ–2 could grow normally at 30℃, alcohol content 15%, SO2 mass concentration 360 mg/L, pH 3.2, sucrose mass concentration 400 g/L and glucose mass concentration 250 g/L. Strain HJ–6 could grow normally at 30℃, alcohol content 3%, SO2 concentration 360 mg/L, pH 3.2, sucrose concentration 250 g/L, glucose concentration 300 g/L. Based on the technological characteristics of fruit wine, S. cerevisiae HJ–2 has the potential of brewing P. fortuneana fruit wine. P. kudriavzevii HJ–6 has a low tolerance to ethanol and is suitable for the production of fermented beverages such as low–alcohol wine or beer. [ABSTRACT FROM AUTHOR]

Family system generally consists of family structure and process, and plays substantial yet varied roles in university students' career decision self-efficacy (CDSE). However, previous research has mainly employed the variable-centered approach, which overlooked the diversities of family systems in light of individuals' CDSE. Adopting latent profile analysis, the present study examined the relationships between various family structural (socioeconomic status) and processual factors (parental career-related support) with CDSE among 917 Chinese undergraduates (Mage = 21.41, SD = 0.84; females, 53.87%). Five distinct family profiles were identified: "powerful and supportive" (N = 377, 41.12%), "powerful but unsupportive" (N = 61, 6.65%), "powerless but supportive" (N = 104, 11.34%), "powerless and unsupportive" (N = 62, 6.76%), and "ordinary powerful and supportive" (N = 313, 34.13%). The scores of CDSE significantly differed among the different family system profiles. The order from the lowest to highest CDSE was "powerless and unsupportive" (M = 3.48, SD = 0.08), "powerful but unsupportive" (M = 3.53, SD = 0.07), "powerless but supportive" (M = 3.74, SD = 0.05), "ordinary powerful and supportive" (M = 3.77, SD = 0.03), to "powerful and supportive" (M = 3.86, SD = 0.03). Additional regression analyses, after controlling for demographic variables, further confirmed the findings from multivariate analysis of variance and follow-up post hoc tests regarding the differences of CDSE among different profiles. The findings underscored family system patterns in shaping CDSE, and provided implications for improving career development among Chinese college students. [ABSTRACT FROM AUTHOR]

Yeast, which plays a pivotal role in the brewing, food, and medical industries, exhibits a close relationship with human beings. In this study, we isolated and purified 60 yeast strains from the natural fermentation broth of Sidamo coffee beans to screen for indigenous beneficial yeasts. Among them, 25 strains were obtained through morphological characterization on nutritional agar medium from Wallerstein Laboratory (WL), with molecular biology identifying Saccharomyces cerevisiae strain YBB-47 and the remaining 24 yeast strains identified as Pichia kudriavzevii. We investigated the fermentation performance, alcohol tolerance, SO2 tolerance, pH tolerance, sugar tolerance, temperature tolerance, ester production capacity, ethanol production capacity, H2S production capacity, and other brewing characteristics of YBB-33 and YBB-47. The results demonstrated that both strains could tolerate up to 3% alcohol by volume at a high sucrose mass concentration (400 g/L) under elevated temperature conditions (40 ℃), while also exhibiting a remarkable ability to withstand an SO2 mass concentration of 300 g/L at pH 3.2. Moreover, S. cerevisiae YBB-47 displayed a rapid gas production rate and strong ethanol productivity. whereas P. kudriavzevii YBB-33 exhibited excellent alcohol tolerance. Furthermore, this systematic classification and characterization of coffee bean yeast strains from the Sidamo region can potentially uncover additional yeasts that offer high-quality resources for industrial-scale coffee bean production. [ABSTRACT FROM AUTHOR]

Copyright of Rare Metals is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Rare Metals is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This research pioneered the investigation of the statistically predictive power of academics' research agendas for their organizational commitment—beyond age, gender, academic rank, and academic discipline. Three hundred and thirty-two academics from nine research-oriented comprehensive universities in Zhejiang province and Shanghai, mainland China, responded to the Multi-Dimensional Research Agendas Inventory-12 Items (MDRAI-12) and the Organizational Commitment Inventory. Three main findings were obtained. First, the MDRAI-12 was confirmed to be a valid and reliable instrument for assessing the research agendas of academics in mainland China. Second, both academics' research agendas and their organizational commitment varied as a function of demographics. Third and most importantly, when age, gender, academic rank, and academic discipline were put under control, three of the four trailblazing research agendas (scientific ambition, collaboration, and discovery) predicted the three adaptive organizational commitments (affective, normative, and ideal), whereas the two cohesive research agendas (convergence and conservative) chiefly contributed to the two maladaptive organizational commitments (economic and choice). These findings have shed new light on the literature concerning research agendas and that on organizational commitment. At the same time, the findings have practical implications for university academics and senior managers in their respective efforts to promote innovative research and adaptive organizational commitment among academics. [ABSTRACT FROM AUTHOR]

This study's principal objective was to explore the statistically predictive power of academics' research agendas for their job dissatisfaction beyond demographics. Five hundred and forty-seven academics from the eight publicly funded universities in Hong Kong responded to the Multi-Dimensional Research Agenda Inventory-12 (MDRAI-12) and the Job Dissatisfaction Scale (JDS). Three key findings were obtained. First, good psychometrics for the MDRAI-12 and the JDS were obtained. Second, research agendas varied by age, gender, academic rank, and academic discipline, while job dissatisfaction varied by age, academic rank, and institutional ranking. Third and most importantly, when age, gender, academic rank, academic discipline, and institutional ranking were statistically controlled, trailblazing research agendas generally negatively contributed to job dissatisfaction, whereas a cohesive (conservative) research agenda positively predicted job dissatisfaction, as hypothesized. Implications of the findings are discussed for academics and university senior managers. [ABSTRACT FROM AUTHOR]

The connecting part of bridge widening undertakes complicated forces and tends to crack. Basic magnesium sulfate cement concrete has excellent properties such as ideal early strength and tensile strength, meeting the performance requirements of joint materials. Experiments of two spliced box girder specimens with C40 basic magnesium sulfate cement concrete (MC) and normal Portland cement concrete (NC) as joint materials are carried out. Concrete strain, reinforcement strain, deflection and crack propagation law of the joint section are tested and analyzed under symmetrical loading at the cantilever of the box girders. The study shows when MC material is used in the splicing section, the joint section showed a multi-cracks failure mode with an ultimate load ratio of 0.99 and a maximum crack width of 1.3 mm; NC joint section has only three longitudinal cracks with an ultimate load ratio of 0.97 and a maximum crack width of 0.98 mm. Under the same load, the crack width and the deflection of mid-span MC joint section are greater than which of NC joint section. The maximum deflection of NC splicing section is 1.20 mm, which is 1/633 of the calculating span length. The maximum deflection of MC spliced section is 2.03 mm, which is 1/374 of the calculating span length. Comparison of the maximum deflection and the maximum crack width shows that MC material has better ductility. [ABSTRACT FROM AUTHOR]

Objectives: Corynebacterium glutamicum (C. glutamicum) has been harnessed for multi-million-ton scale production of glutamate and lysine. To further increase its amino acid production for fermentation industry, there is an acute need to develop next-generation genome manipulation tool for its metabolic engineering. All reported methods for genome editing triggered with CRISPR-Cas are based on the homologous recombination. While, it requires the generation of DNA repair template, which is a bottle-neck for its extensive application. Results: In this study, we developed a method for gene knockout in C. glutamicum via CRISPR-Cpf1-coupled non-homologous end-joining (CC-NHEJ). Specifically, CRISPR-Cpf1 introduced double-strand breaks in the genome of C. glutamicum, which was further repaired by ectopically expressed two NHEJ key proteins (Mycobacterium tuberculosis Ku and ligase D). We provide the proof of concept, for CC-NHEJ, by the successful knockout of the crtYf/e gene in C. glutamicum with the efficiency of 22.00 ± 5.56%, or something like that. Conclusion: The present study reported a novel genome manipulation method for C. glutamicum. [ABSTRACT FROM AUTHOR]

This study explored factors that influence academics to collaborate in research with their doctoral students. It focused on Hong Kong academics, using data from the Academic Profession in Knowledge Society survey conducted in 2017–2018. The study found that academics' research collaboration with doctoral students is influenced by several factors, including research and teaching styles and institutional conditions. Specifically, those academics whose research agendas were characterised by discovery and collaboration were more likely to report working with their doctoral students, whereas those whose research agendas focused more on convergence were less likely to do so. The more legislative the academics' teaching style was, the less they collaborated with their doctoral students. Independence in research and institutional expectations of external funding increased the propensity to collaborate with doctoral students. Academics in the humanities were found to collaborate less with their doctoral students than those in other disciplines. The study suggests that the scholarly preference and styles of the academics, as well as their disciplinary and institutional backgrounds, need to be considered to improve research collaboration between academics and their doctoral students. [ABSTRACT FROM AUTHOR]

Present study was designed to compared the total flavonoids and polyphenols contents and antibacterial activity of hawthorn extracts with different polarities as well as the underlying antibacterial mechanisms. The results showed that among all hawthorn extracts, methanol and ethanol extracts (ME and EE) exhibited high levels of total flavonoids and polyphenols contents, followed by acetone, ethyl acetate, trichloromethane and petroleum ether extracts. ME exhibited the strongest antibacterial activity against tested bacteria, especially Staphylococcus aureus with a 1.25 μg/mL of the minimum inhibitory concentration (MIC) and minimum bactericide concentration (MBC). Further analysis revealed that the main phenolic compounds from ME were epicatechin (281.6 mg/100 g DW), procyanidin B2 (243.5 mg/100 g DW), chlorogenic acid (84.2 mg/100 g DW) and quercetin (78.4 mg/100 g DW). The action mechanism of ME against S. aureus could be ascribed to ME damaging cell wall and cell membrane integrity, inhibiting intracellular enzyme activity, increasing reactive oxygen species (ROS), also changing expression of associated genes and then inducing apoptosis of S. aureus. In addition, the antimicrobial activity of ME against S. aureus has also been demonstrated to be efficient in the food matrix (whole milk). [ABSTRACT FROM AUTHOR]

Recent developments in higher education have placed greater emphasis on performance and accountability and raised concerns about increasing levels of stress among academics. Stress not only influences academic productivity but may also affect institutional commitment, which is key to guaranteeing academics' organisational stability, identity and performance at the university. This study examines how the stress of academics working in Hong Kong, which has a highly competitive and performativity oriented higher education system, relates to an institutional commitment to their universities. Through the use of a methodology that handles endogeneity bias, this relationship was analysed using socio-demographic data, information on characteristics of the institutional environment, and academic-work-related data from the Academic Profession in Knowledge Society (APIKS) questionnaire conducted in Hong Kong in 2017/2018. The main finding of this study is that the more the job becomes a strain, the greater the academic's institutional commitment to the university. We argue that stress was positively associated with greater institutional commitment due to Hong Kong's competitive working culture, as no statistically significant differences in stress and institutional commitment were found among those in different academic fields of knowledge and universities. Analysis of determinants of stress and institutional commitment showed that independence in research, interest in current work, availability of career opportunities, and collegial decision-making reduced stress and increased institutional commitment. Conversely, pressure to obtain external funding and excessive administrative work increase stress and reduce institutional commitment. Based on these findings, universities should institute balanced policies that promote research autonomy, collegiality and flexible career opportunities in academic work, whilst designing new ways to more congenially integrate the ubiquitous demand for external funding into academic life, and minimising administrative procedures which are not attuned with creative academic environments. [ABSTRACT FROM AUTHOR]

Objectives: The low incidence yet severe presentation of medication-related osteonecrosis of the jaw (MRONJ) makes it necessary to develop reliable predictive and preventive strategies. This study explored the value of pre-operative carboxy-terminal collagen crosslinks (CTX) serum level in the prediction of osteonecrosis-related complications in patients on bisphosphonate therapy.Patients and methods: We examined patient records over 4 years (a total of 137 patients). Biometric data were extracted, in addition to type of treatment, CTX levels, drug holiday, procedure, complications, and co-morbidities. Non-parametric Wilcoxon two-sample tests were used to test the effect of initial CTX level in IV or PO and whether it was predictive of complications. Two independent proportion tests were used for testing the two different complication incident rates before or after the drug holiday.Results: A total of 93 patients were included in the study, of whom 88.17% were female. A total of 11 patients were receiving IV bisphosphonates at the time of initial presentation, 82 oral bisphosphonates. Out of 64 patients who underwent invasive dental procedure (IDP) before a drug holiday, eight were on IV bisphosphonates. Three patients in this group experienced osteonecrosis-related complications (37.5%). Out of the remaining 56 patients on oral bisphosphonates, four (7.14%) developed complications, significantly lower than the IV bisphosphonate group (p = 0.0364). On the other hand, of the 34 patients placed on a drug holiday prior to IDP, only one subject developed complications related to osteonecrosis. Five subjects who had operations both before and after drug holiday did not experience any complications. No statistical difference was detected in complication rates based on initial CTX level (above versus below 150 pg/ml), gender, comorbidities, or total duration of bisphosphonate treatment (p = 0.2675). The sensitivity and specificity of CTX cutoff of 150 pg/ml in predicting osteonecrosis were 37.5% and 57.7, respectively.Conclusions: Serum levels of CTX by itself are not reliable as a predictive or preventive measure for such complications. Our data also suggested that a drug holiday of 5 months was not helpful in preventing osteonecrosis-related complications in patients on intravenous bisphosphonates. Further studies are urgently needed to develop adequate predictive and preventive strategies of MRONJ. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Acupuncture & Tuina Science is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This study investigated the extent to which learning approaches can be accounted for by personal factors (i.e., demographics, ability, and personality). The participants were 443 students in a university in mainland China. The Revised Two-factor Study Process Questionnaire, the NEO Five-Factor Inventory-3, and the short form of Raven's Advanced Progress Matrices were respectively applied to test students' learning approaches, personality, and ability. The results of correlations and structural equation modeling indicated that male students were more likely to be deep learners than female students; relative to Year-one students, Year-three students were more likely to use the surface learning approach and less likely to use the deep learning approach. Openness to experience and conscientiousness had strong positive effects on the deep learning approach. Neuroticism had positive effect, whereas conscientiousness had negative effect on the surface learning approach. Approximately 44 % of the variance in the deep learning approach and approximately 18 % of the variance in the surface learning approach could be explained by the three personal factors. Personality was the strongest predictor of learning approaches, whereas ability was the weakest predictor. The implications of the results were discussed. [ABSTRACT FROM AUTHOR]

For long, the research-teaching nexus has maintained the interest of the scholarly community. The present study introduced a process variable-teaching styles-into the investigation of the association between research and teaching. The study adopted a predominantly quantitative-driven, mixed research method design, with a questionnaire survey supplemented by insiders' views. Three hundred and fifty-four academics from 15 institutions in Beijing, P. R. China, responded to the Thinking Styles in Teaching Inventory and reported their research publications for 3 years. The quantitative findings suggested that after key demographics and contextual factors were controlled for, teaching styles were related to research productivity largely in the anticipated directions. Subsequently, four additional academics who met the criteria of possessing expertise in teaching styles and of having experiences as academics in China were invited to explain the quantitative findings concerning the relationships between specific teaching styles and particular types of publications. It was concluded that although the magnitude of the relationship between teaching and research is rather small, the research-teaching nexus does exist. Theoretical significance is discussed and practical implications of the findings are proposed for academics and for university senior managers. [ABSTRACT FROM AUTHOR]

Intellectual styles refer to people's preferred ways of processing information and dealing with tasks. Individuals who have a propensity for using a wide range of styles-always including creativity-generating styles-are said to possess successful intellectual styles. The author argues that teachers should and can encourage creativity among students by cultivating successful intellectual styles. To make this argument, the author first presents two main controversial issues over the nature of intellectual styles: style value and style malleability. She then cites research evidence revealing that creativity-generating intellectual styles are more adaptive than are norm-favoring styles; that the positive growth in some domains of student learning and development calls for successful intellectual styles; and that styles can be developed. Following this, the author points out the limitations of the existing research and suggests ways to overcome the limitations. Finally, the author proposes strategies that teachers could use in promoting creativity through fostering successful intellectual styles among students. [ABSTRACT FROM AUTHOR]

Aim:To investigate the potential interactive effects of a high-fat diet (HFD) and valproic acid (VPA) on hepatic steatosis and hepatotoxicity in rats.Methods:Male SD rats were orally administered VPA (100 or 500 mg·kg−1·d−1) combined with HFD or a standard diet for 8 weeks. Blood and liver samples were analyzed to determine lipid levels and hepatic function biomarkers using commercial kit assays. Low-molecular-weight compounds in serum, urine and bile samples were analyzed using a metabonomic approach based on GC/TOF-MS.Results:HFD alone induced extensive hepatocyte steatosis and edema in rats, while VPA alone did not cause significant liver lesions. VPA significantly aggravated HFD-induced accumulation of liver lipids, and caused additional spotty or piecemeal necrosis, accompanied by moderate infiltration of inflammatory cells in the liver. Metabonomic analysis of serum, urine and bile samples revealed that HFD significantly increased the levels of amino acids, free fatty acids (FFAs) and 3-hydroxy-butanoic acid, whereas VPA markedly decreased the levels of amino acids, FFAs and the intermediate products of the tricarboxylic acid cycle (TCA) compared with the control group. HFD aggravated VPA-induced inhibition on lipid and amino acid metabolism.Conclusion:HFD magnifies VPA-induced impairment of mitochondrial β-oxidation of FFAs and TCA, thereby increases hepatic steatosis and hepatotoxicity. The results suggest the patients receiving VPA treatment should be advised to avoid eating HFD. [ABSTRACT FROM AUTHOR]

Poly(etheretherketone) (PEEK) is a rigid semicrystalline polymer that exhibits excellent mechanical properties and bone-like stiffness and is widely used in biomaterials. However, the development of PEEK-based bioinert materials has been impeded because PEEK lacks bioactivity. In this study, a series of PEEK/carbon nanotubes (CNTs)/bioactive glass (BG) ternary nanocomposites were produced using injection molding. BG was added to the composites in order to improve the bioactivity of the PEEK, and a novel method of adsorption and co-precipitation was used to add the CNTs to the composites in order to compensate for the deterioration in the mechanical properties of the PEEK caused by the addition of the BG. The microstructures of the composites were investigated using scanning electron microscopy (SEM), and the SEM images revealed that this method permits the uniform dispersion of the CNTs throughout the PEEK matrix. Further, the mechanical properties of the composites were significantly enhanced by the addition of the CNTs. The highest content of CNTs in the composites was 6 wt%. The composites containing 6 wt% CNTs and 4 wt% BG exhibited the same mechanical strength as the pure PEEK. The bioactivity of the PEEK when immersed in simulated body fluid (SBF) was improved by incorporating BG into the composites. These new ternary composite materials which exhibit satisfactory mechanical properties and a high degree of bioactivity have great potential to meet the demand for bone-substitute materials. [ABSTRACT FROM AUTHOR]

A new one-dimensional cyanide-bridged Cr-Mn complex [Cr(bpb)(CN)][Mn(bpb)]·2CHOH [bpb = 1,2-bis(pyridine-2-carboxamido)benzenate] ( 1) has been synthesized by the reaction of [Mn(bpb)(HO)]ClO and K[Cr(bpb)(CN)]. The single-crystal X-ray diffraction analysis shows that the structure of complex 1 is a one-dimensional coordination polymer type with two different metal centers which is alternated linked by cyanide group from the K[Cr(bpb)(CN)] building blocks. Magnetic investigations reveal that the magnetic interaction between Cr(III) and high-spin Mn(III) ions through the cyanide bridge is weak antiferromagnetic coupling. [ABSTRACT FROM AUTHOR]

Purpose: The aim of this study was to investigate the genetic polymorphisms of UGT1A3, UGT1A6, and UGT2B7 in Chinese epilepsy patients and their potential influence on the pharmacokinetics of valproic acid (VPA). Methods: The genetic architectures of UGT1A3, UGT1A6, and UGT2B7 in 242 epilepsy patients were detected by DNA sequencing and PCR-restriction fragment length polymorphism. Steady-state plasma concentrations of VPA in 225 patients who had received VPA (approx. 250-1,000 mg/day) for at least 2 weeks were determined and associated with UGT polymorphisms. Results: The allelic distribution of UGT1A3 in our Chinese epilepsy patients was significantly different from that in healthy subjects based on reference data. The standardized trough plasma concentration (C) of VPA was much lower in our patients with the UGT1A3*5 variant than in the wild type carriers (3.24 ± 1.05 vs. 4.68 ± 1.24 μg·kg·mL·mg, P < 0.01). UGT polymorphisms had no influence on the pharmacokinetic interactions between carbamazepine and VPA. Conclusion: Our results suggest that UGT1A3*5 may be an important determinant of individual variability in the pharmacokinetics of VPA and that it may be necessary to increase VPA dose for UGT1A3*5 carriers to ensure its therapeutic range of 50-100 μg/mL. [ABSTRACT FROM AUTHOR]

Three cyanide-bridged Fe-Mn binuclear complexes [Mn(phen)Cl][Fe(bpmb)(CN)]·HO ( 1), [Mn(phen)Cl][Fe(bpdmb)(CN)]·HO ( 2) and [Mn(phen)Cl][Fe(bpClb)(CN)]·3HO·EtOH ( 3) [phen = 1,10-phenanthroline, bpmb = 1,2-bis(pyridine-2-carboxamido)-4-methyl-benzenate, bpdmb = 1,2-bis(pyridine-2-carboxamido)-4,5-dimethyl-benzenate, bpClb = 1,2-bis(pyridine-2-carboxamido)-4-chloro-benzenate)] have been synthesized by the reaction of Mn(phen)Cl with K[Fe(L)(CN)]. The syntheses, crystal structures and magnetic properties of the complexes have been investigated. Single-crystal X-ray diffraction analysis reveals that all three complexes are binuclear complexes and contain Fe-C≡N-Mn linkages. Magnetic investigations indicate antiferromagnetic coupling between low-spin Fe(III) and high-spin Mn(II) centers through cyanide bridging, with J = −1.39(5) cm for 1, J = −3.33(2) cm for 2 and J = −1.96(5) cm for 3. The magneto-structural relationships for cyanide-bridged Fe-Mn systems are discussed based on binuclear Fe-Mn and trinuclear Fe-Mn-Fe magnetic models. [ABSTRACT FROM AUTHOR]

biodegradable and thermoplastic elastomer-poly( L-lactide- co-ε-caprolactone) (PLLCA)-was reinforced with 5, 10, 20, and 30 wt% of CaCO whiskers. We assessed the influence of the CaCO whisker content on the mechanical and thermal properties of the PLLCA/CaCO whisker composites. Scanning electron microscopy (SEM) revealed that the CaCO whiskers were uniformly distributed in the composite matrices. The results of differential scanning calorimetry (DSC) and dynamic mechanical analysis (DMA) showed that the glass transition temperatures ( T) of the composites increased slightly with increasing CaCO whisker content. At low CaCO whisker contents, the tensile strengths of the composites increased sharply with increasing CaCO content, the Young's moduli also increased, and the elongation at break values gradually decreased. Thermogravimetric analysis (TGA) showed that the CaCO whiskers can promote the thermal degradation of PLLCA. Shape memory test results indicated that an appropriate amount of CaCO whiskers can improve the shape memory properties of PLLCA. [ABSTRACT FROM AUTHOR]

Rare earth aryloxides substituted by various alkyl groups [Ln(OAr)] such as methyl, isopropyl and tertbutyl, were used as single component catalysts to affect ring-opening polymerization of L-lactide (LLA). The catalytic activity, polymerization characteristics, polymerization kinetics and the mechanism were studied. It was found that the catalytic activity of rare earth aryloxides is influenced by both the structure and the number of alkyl groups on the phenyl ring. The stronger the electron-donation ability of the alkyl group, the higher the catalytic activity will be. An increase in the number of the substitute group will result in a higher catalytic activity. Lanthanum tris(2,4,6-tri- tert-butylphenolate) [La(OTTBP)] exhibits the highest activity among all lanthanum aryloxides. According to the H-NMR data, it was proposed that the LLA polymerization proceeded via a coordination-insertion mechanism involving cleavage of acyl-oxygen bond of the lactide. [ABSTRACT FROM AUTHOR]

The purpose of this research was to provide cross-cultural evidence of the relationship between student approaches to learning and stages of cognitive development and of the validity of Perry's theory of such development. The participants for this study were 67 U.S. and 193 Mainland Chinese students. The participants rated their ability on several scales, responded to the Zhang Cognitive Development Inventory (Zhang 1995) and the Study Process Questionnaire (Biggs 1987a, 1992) as well as a demographic questionnaire. Self-report measures of achievement scores were also obtained. There were four major findings. First, cognitive development and student learning approaches were related in predictable ways. Second, the cognitive-developmental patterns of the American and Chinese participants differed. Third, for both American and Chinese students, extracurricular activities positively contributed to their cognitive development. Finally, a statistically significant relationship between cognitive development and achievement was identified among the American group, whereas no relationship was found between cognitive development and achievement among the Chinese group. Implications of these findings are discussed. [ABSTRACT FROM AUTHOR]

The article discusses a study which investigated the volatile components of Ainsliaea (A.) pertyoides' essential oils. The essential oils were obtained from dried and fresh materials of Ainsliaea pertyoides. It reveals that the major constituents of the oils from the materials include sesquiterpenes, aliphatics, and monoterpenes.