title: The preparation and characterisation of monomeric and linked metal carbonyl clusters containing the closo-Si2Co4 pseudo-octahedral core

authors: Evans, Cameron

abstract: PhSiH3 reacts with [Co₄(CO)₁₂] at 50 °C in hydrocarbon solvents to give [(µ₄-SiPh)₂Co₄(CO)₁₁], 2c, shown by an X-ray crystal structure determination to have a pseudo-octahedral Si₂Co₄ core. Substituted aryl-silanes behaved similarly. Mixtures of PhSiH₃, H₃SiC₆H₄SiH₃ and [Co₄(CO)₁₂] in a ca. 2  1  2 ratio gave the dimeric cluster [{Co₄(µ₄-SiPh)(CO)₁₁Si}₂C₆H₄], 3a, which has the two Si₂Co₄ cores linked by a C₆H₄ group to give a rigid molecule which an X-ray structure analysis shows to be over 23 Å long. Related dimers linked by –(CH₂)₈– groups were isolated from mixtures of PhSiH₃, α ,ω-(H₃Si)₂(CH₂)₈ and [Co₄(CO)₁₂]. Electrochemical studies show the two cluster units in 3a do not interact electronically.

text: The preparation and characterisation of monomeric and linked metal carbonyl clusters containing the closo-Si2Co4 pseudo-octahedral core PhSiH3 reacts with [Co₄(CO)₁₂] at 50 °C in hydrocarbon solvents to give [(µ₄-SiPh)₂Co₄(CO)₁₁], 2c, shown by an X-ray crystal structure determination to have a pseudo-octahedral Si₂Co₄ core. Substituted aryl-silanes behaved similarly. Mixtures of PhSiH₃, H₃SiC₆H₄SiH₃ and [Co₄(CO)₁₂] in a ca. 2  1  2 ratio gave the dimeric cluster [{Co₄(µ₄-SiPh)(CO)₁₁Si}₂C₆H₄], 3a, which has the two Si₂Co₄ cores linked by a C₆H₄ group to give a rigid molecule which an X-ray structure analysis shows to be over 23 Å long. Related dimers linked by –(CH₂)₈– groups were isolated from mixtures of PhSiH₃, α ,ω-(H₃Si)₂(CH₂)₈ and [Co₄(CO)₁₂]. Electrochemical studies show the two cluster units in 3a do not interact electronically.

year: 2002-01-01

title: Determining word–emotion associations from tweets by multi-label classification

authors: Bravo-Marquez, Felipe

subjects: computer science

abstract: The automatic detection of emotions in Twitter posts is a challenging task due to the informal nature of the language used in this platform. In this paper, we propose a methodology for expanding the NRC word-emotion association lexicon for the language used in Twitter. We perform this expansion using multi-label classification of words and compare different wordlevel features extracted from unlabelled tweets such as unigrams, Brown clusters, POS tags, and word2vec embeddings. The results show that the expanded lexicon achieves major improvements over the original lexicon when classifying tweets into emotional categories. In contrast to previous work, our methodology does not depend on tweets annotated with emotional hashtags, thus enabling the identification of emotional words from any domainspecific collection using unlabelled tweets.

text: Determining word–emotion associations from tweets by multi-label classification The automatic detection of emotions in Twitter posts is a challenging task due to the informal nature of the language used in this platform. In this paper, we propose a methodology for expanding the NRC word-emotion association lexicon for the language used in Twitter. We perform this expansion using multi-label classification of words and compare different wordlevel features extracted from unlabelled tweets such as unigrams, Brown clusters, POS tags, and word2vec embeddings. The results show that the expanded lexicon achieves major improvements over the original lexicon when classifying tweets into emotional categories. In contrast to previous work, our methodology does not depend on tweets annotated with emotional hashtags, thus enabling the identification of emotional words from any domainspecific collection using unlabelled tweets.

year: 2016

title: Raising Māori Medium Students' Academic Oral Language Proficiency Through Self and Peer Assessment

authors: Shandley, Rosina Mary

subjects: Māori Medium Education

abstract: In 2012 there were 24,474 year 1 to 8 students being educated in the range of Māori medium bilingual and immersion programmes that exist throughout Aotearoa. This figure made up 25% of the total primary school population.

To ensure the survival of te reo Māori, and the cognitive advantages associated with bilingualism, Māori medium students need to reach a high level of proficiency in both the English and Māori languages over their time at school. They need to develop their language skills beyond basic conversational competency to academic language proficiency.

As well as academic success, Māori medium whānau expect their students to gain a level of competence in te reo Māori that enables them to actively engage in authentic Māori cultural contexts. This is crucial as the interruption to the intergenerational transfer of te reo Māori caused by colonisation means that today Māori medium graduates make up the main pool of speakers who can transmit our language into the future.

Substantial research has evidenced effective pedagogies for supporting students’ second language acquisition internationally. However, to date there have been no empirical studies to evidence effective second language pedagogies that can raise Māori medium students’ academic language in particular. This study aimed to bridge that gap by providing evidence of effective classroom practices that can raise Māori medium students’ academic language proficiency, with a particular focus on oral language competency.

This action research project aimed to raise a group of Māori medium students’ academic oral language proficiency through the practice of self and peer assessment. The participants were a group of eight year 5 and 6 students being educated in a level one Māori medium classroom in a mainstream school in Southland, New Zealand.

Over the 20 weeks of the study the students used a newly developed language matrix of writing outcomes to self and peer assess their learning in their literacy programme. The quantitative and qualitiative results of the study revealed that the confluence of self and peer assessment practices and the new language scaffolds raised the students’ academic oral and written language competency significantly beyond what was normally expected in a Māori medium programme in 20 weeks.

The study findings provide an option for those teachers wishing to develop their Māori medium students’ academic Māori language proficiency. The study also highlights the need for further research into Māori language acquisition pathways, to inform Māori medium oral language progressions and associated assessment development.

text: Raising Māori Medium Students' Academic Oral Language Proficiency Through Self and Peer Assessment In 2012 there were 24,474 year 1 to 8 students being educated in the range of Māori medium bilingual and immersion programmes that exist throughout Aotearoa. This figure made up 25% of the total primary school population.

To ensure the survival of te reo Māori, and the cognitive advantages associated with bilingualism, Māori medium students need to reach a high level of proficiency in both the English and Māori languages over their time at school. They need to develop their language skills beyond basic conversational competency to academic language proficiency.

As well as academic success, Māori medium whānau expect their students to gain a level of competence in te reo Māori that enables them to actively engage in authentic Māori cultural contexts. This is crucial as the interruption to the intergenerational transfer of te reo Māori caused by colonisation means that today Māori medium graduates make up the main pool of speakers who can transmit our language into the future.

Substantial research has evidenced effective pedagogies for supporting students’ second language acquisition internationally. However, to date there have been no empirical studies to evidence effective second language pedagogies that can raise Māori medium students’ academic language in particular. This study aimed to bridge that gap by providing evidence of effective classroom practices that can raise Māori medium students’ academic language proficiency, with a particular focus on oral language competency.

This action research project aimed to raise a group of Māori medium students’ academic oral language proficiency through the practice of self and peer assessment. The participants were a group of eight year 5 and 6 students being educated in a level one Māori medium classroom in a mainstream school in Southland, New Zealand.

Over the 20 weeks of the study the students used a newly developed language matrix of writing outcomes to self and peer assess their learning in their literacy programme. The quantitative and qualitiative results of the study revealed that the confluence of self and peer assessment practices and the new language scaffolds raised the students’ academic oral and written language competency significantly beyond what was normally expected in a Māori medium programme in 20 weeks.

The study findings provide an option for those teachers wishing to develop their Māori medium students’ academic Māori language proficiency. The study also highlights the need for further research into Māori language acquisition pathways, to inform Māori medium oral language progressions and associated assessment development.

year: 2013