Solid-phase microextraction for flavor analysis in Harari Khat (Catha edulis) stimulant

This research examined the typical flavor compounds in the commonest type of Khat called Harari Khat grown in the region of Ethiopia. Twenty-eight compounds, which includes 1,2-Propanedione, 1-Phenyl, Hexanol, Hexanal compounds, Limonene, Benzaldehyde with other flavors, were extracted by polydimethylsiloxane at room temperature for 30 min from Khat samples, and identified by solid-phase microextraction-gas chromatography-mass spectrometry (SPME- GC-MS). This method needs no organic solvents and required minimal sample.     

Solid-phase microextraction for flavor analysis in Harari Khat (Catha edulis) stimulant

INTRODUCTIONKhat,achemicalextractedfromaplantCathaEdulis,belongingtothefamilyCelastraceae,isusedasanaturalstimulantinEastAfricaandbor-deringArabicstates.OthernamesbywhichKhatisknowninclude:Catha,qat,kat,chat,kuses-salahin,mirra,tohai,tschat,quat,africanteaandafricansalad.TheplantofCathaedulisisanevergreenfloweringtreeorlargeshrubfoundinEthiopiaandspreadwidelyinKenya,Nyasalnd(nowMalawi),Uganda,Tanganyika,Tanzania,Somalia,Djibouti,andYemen.Itattainsaheightrangingfrom3to4m(Lewis,1931…     

蒙古语复合词的语法属性描述

笔者以分类法和属性描述的方法,对蒙古语复合词的语法属性进行详细的描述,使复合词的各种语法属性更加具体化、条理化,作为语法属性字段附在每一个词语后面,以便为研制电子版蒙古语复合词语法信息词典提供理论依据。     

配位聚合物材料的原位合成

配位聚合物通常是指以金属离子或金属簇为中心,以有机配体为联结体,通过金属离子与有机配体之间的配位作用而形成的具有周期性网络结构的一类化合物.为了能得到结构新颖、功能独特的晶体材料,一些非常规的合成方法诸如原位合成法被发现和采用,本论文着重综述了配位聚合物的原位合成策略.     

硝酸盐作地浸采铀氧化剂若干问题的研究

该文报道了关于硝酸盐作为地浸采铀氧化剂时NO_3~-的消耗、积累和降解产物的热力学分析及试验研究情况,指出NO_3~-的积累主要来源于NO_3~-型贫树脂吸附浸出液初期,而NO_3~-的降解产物主要是NO_2~-,从而为克服NO_3~-的积累和以氮化物为主要治理对象的地浸矿山环保工作的开展指明了方向。     

Teachers’ beliefs, instructional behaviors, and students’ engagement in learning from texts with instructional pictures

This study investigated the relations between teachers’ pedagogical beliefs and students’ self-reported engagement in learning from texts with instructional pictures. Participants were the biology, geography, and German teachers of 46 classes (Grades 5-8) and their students. Teachers’ instructional behaviors and students’ engagement in learning from texts with instructional pictures were assessed by means of student ratings. Teachers’ beliefs about using texts with instructional pictures in their teaching were assessed by a self-report questionnaire. Results showed that the more teachers believed that students should be taught clear strategies on how to learn from texts with instructional pictures the more engagement was reported by their students. A multilevel mediation model showed that the association between teachers’ beliefs and students’ self-reported engagement was mediated by teachers’ perceived instructional behavior.     

Use of Support Vector Regression Based on Mean Impact Value Model to Identify Active Compounds in a Combination of <Emphasis Type="Italic">Curcuma longa</Emphasis> L. and <Emphasis Type="Italic">Glycyrrhiza</Emphasis> extracts

A support vector regression based on the mean impact value (MIV) model was constructed to identify the bioactive compounds inhibiting proliferation of HeLa cells in a combination of turmeric (Curcuma longa L.) and liquorice (Glycyrrhiza) extracts. The quantitative chemical fingerprint from 50 batches of turmeric and liquorice extracts was established using high performance liquid chromatography hyphenated to an ultraviolet visible detector. Qualitative results were obtained using ultra performance liquid chromatography coupled with electrospray ionization quadrupole time-of-flight tandem mass spectrometry. A total of 46 peaks (peaks 1–15 from turmeric and 16–46 from liquorice) were selected as “common peaks” for analysis. The inhibitory effect of the combined extracts on HeLa cells was measured by MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay. It was found that 15 compounds (peaks: 8, 12, 30, 24, 46, 11, 14, 9, 3, 1, 44, 18, 7, 45 and 43) possessing high absolute MIV exhibited a significant correlation with the cytotoxicity against HeLa cells; most of these have already been confirmed with potential cytotoxicity in previous research. The important potential application of the present model can be extended to help discover active compounds from complex herbal medicine prior to traditional bioassay-guided separation. It is considered that this could be a useful tool for re-developing herbal medicine based on the use of these active compounds.     

Chemical composition of the essential oil from <Emphasis Type="Italic">Rabdosia lophanthoides</Emphasis>

Gas chromatography/mass spectrometry (GC-MS) of the essential oil from the aerial parts of Rabdosia lophanthoides resulted in the identification of 108 compounds representing 78. 120% of the oil. Hydro-distillation of Rabdosia lophanthoides yielded a pale yellow oil. The compounds identified and their relative proportions are listed in Table 1 according to their order of elution on an HP-5 MS capillary column.     

The impact of the secure custodial setting on re-engaging incarcerated children with education and learning – A case study in the UK

As many as 90 % of incarcerated children and young people enter the secure setting disengaged from education. The nature of the secure custodial setting compounds the complex and challenging needs of the children, though efforts to understand this are limited. This paper reports on an ethnographic case study in one secure children’s home in England. Findings show that children can be re-engaged with education, relatively easily within a short space of time, given the right conditions. However, the secure setting was a defining feature, shaping the extent of this engagement. The implications of these findings are discussed and recommendation made.     

Antibacterial and anti-biofilm activity of the lipid extract from <Emphasis Type="Italic">Mantidis ootheca</Emphasis> on <Emphasis Type="Italic">Pseudomonas aeruginosa</Emphasis>

The aim of this study is to assess the antibacterial and anti-biofilm properties of the lipid extract from Mantidis ootheca against the gentamycin resistant Pseudomonas aeruginosa. The chemical composition of the lipid extract and its relative proportion were determined using the technique of gas chromatography coupled with mass spectrometry (GC-MS). Antibacterial susceptibility tests were performed using a disc diffusion assay and the minimum inhibition concentration (MIC) was determined by way of the agar dilution method. The anti-biofilm test was carried out with crystal violet staining and scanning electron microscopy (SEM). There were 16 compounds detected, and the most abundant components were sesquiterpenoids, monoterpenes, and trace aromatic compounds. The MIC for P. aeruginosa was 4 mg/ml and the eradication effect on preformed biofilms was established and compared with a ciprofloxacin control. The results of our study indicated that a lipid extract from M. ootheca could be used as a topical and antibacterial agent with anti-biofilm activity in the future.     

颜师古注释用语“今”所言唐代通语研究

颜师古在训诂著作中,常用注释用语＂今＂来指称唐代通语,说明从东汉到唐代汉语词语的演变发展轨迹。这些唐代通语与被释词相比较,在形态上,主要有一成不变、貌合神离、改头换面、面目全非等四种变化,而以后两种为主。在构词法上,单音词演变为复音词,以合成词为主且偏正式最多。今天仍有一部分唐代通语作为现代汉语基本词汇、一般词汇或方言词汇在沿用。     

浅谈数词在汉译俄中的译法

本文从七个方面阐述了汉俄两种语言中数词的不同特点及其用法，提出了数词在汉译俄的翻译中常碰到的一些问题，并针对这些问题提出解决办法。     

Examining Predictors of Counselor‐in‐Training Intentional Nondisclosure

This study explored factors that best predict intentional nondisclosure by counselors‐in‐training (CITs) during onsite supervision, including social judgment about one’s supervisor, the supervisory working alliance (SWA), and supervisee attachment styles. Stepwise regression in a sample of 146 CITs revealed that the SWA and supervisee attachment avoidance predicted 60% of the variance in intentional nondisclosure.     

“以赛促学”模式优化设计——基于协同学习理论场域视角

以赛促学是提高教学质量和培养人才的有效途径。为优化技能类课程教学模式,从协同学习理论的场域视角出发,分析传统竞赛模式中影响促学效率的多维要素。结合场域理论进行系统分析,参考支持协同学习的教学过程模型,从认知、动作、情感层次方面对以赛促学模式进行系统优化设计。以《现代教育技术》课程为例开展“以赛促学”。实证分析表明,该模式强化了深层知识构建,有利于全面提升师生素养,提高学习效率。     

Teaching poetry: writing poetry — teaching as a writer

This paper considers the ways in which the authentic strategies and struggles of the creative writer in formulating a text, can be translated into classroom activity. It explores four activities which derived from my own practice as a writer, and demonstrates the process of adapting, trialling and evaluating them in a range of different classroom settings. The paper attempts to answer the questions: w ere these ‘real‐life’ processes successful as a basis for learning activities? How did the learners respond and what can we learn from heir responses? The paper concludes with the premise that being congruent with one's own ‘real‐life’ strategies can indeed lead to valid learning activities, and that these activities help us to deconstruct many of the myths about what it means to be creative.     

“You choose to care”: Teachers,emotions and professional identity

This paper discusses the findings of a qualitative interpretive study on secondary school teachers’ professional identities and emotional experiences. Teachers’ work is emotionally engaging and personally demanding, yet the caring nature of the teaching role is largely neglected in educational policy and teacher standards. This paper examines the reasons behind the marginalisation of discourses of emotionality and discusses the lived experiences of three teachers. The caring behaviour that teachers exhibit in their work is seen to have professional, performative and philosophical dimensions as individual teachers subjectively negotiate the demands that are placed upon them in different situated contexts.     

多义复合词的词义与语素义关系计量分析

通过计量的方式从微观层面来研究多义词,即多义复合词的词义与其构成成分——语素义之间的关系,结果表明：语素的多义性使复合词也具有多义性。或者说复合词的多义性来源于构词语素的多义性。由语素的多义性产生的多义复合词,其词义基本上可以由语素的字面意义获得。     

地瓜藤提取物的GC-MS成分研究

目的：研究地瓜藤（Ficus tikoua Bur）石油醚及乙酸乙酯提取部分的化学成分。方法：地瓜藤经乙醇渗漉提取,采用溶剂提取法进行分离纯化,得到的单体化合物,根据理化方法及气相色谱-质谱联用分析鉴定法鉴定其结构。结果：分离出穿贝海绵甾醇、邻苯二甲酸二丁酯、4-羟基-3-甲氧基苯甲酸、邻苯二甲酸二异丁酯、邻苯二甲酸二乙基己基酯、十八酸等33种化学成分,其中32种化合物是首次从该种植物中提取得到的。     

The role of teachers’ orientation to learning in professional development and change: A national study of teachers in England

This paper uses results from a national survey of teachers in England to test a hypothesised model of teacher orientation to learning (consisting of beliefs, practice and experiences about learning) and its relationship to teacher learning change. Results from a structural equation modeling process of 1126 teacher survey responses show that teachers bring an internal, external and collaborative orientation to their professional learning. The beliefs and practices associated with these orientations are also shown to have a moderate influence, via path analysis, on teacher learning change defined as a composite outcome of change in beliefs, practices and students.