Hydroalumination of Thioacetylenes: A Versatile Generation and Reactions of -Aluminate Sulfides Intermediates

Hydroalumination of thioacetylenes using DIBAL-H and lithium di-(isobutyl)-n-(butyl)-aluminate hydride (Zweifel's reagent), followed by addition of water, furnished exclusively the (Z)- and (E)-vinyl sulfides, respectively. The regio- and stereochemistry of the intermediates generated, (Z)- and (E)-phenylthio vinyl alanates, were determined by capture with iodine, which afforded the corresponding (E)- and (Z)-1-iodo-1-phenylthio-2-organoyl ethenes. Reactions of the (E)-iodo(thio)ketene acetals with n-BuLi followed by addition of hexanal afforded the (Z)-phenylthio allylic alcohol, while the (Z)-iodo(thio)ketene acetals under similar reactions conditions gave the (E)-phenylthio allylic alcohol exclusively.

Parsing, Generation and Grammar

Humans use their grammatical knowledge in more than one way. On one hand, they use it to understand what others say. On the other hand, they use it to say what they want to convey to others (or to themselves). In either case, they need to assemble the structure of sentences in a systematic fashion, in accordance with the grammar of their language. Despite the fact that the structures that comprehenders and speakers assemble are systematic in an identical fashion (i.e., obey the same grammatical constraints), the two ‘modes’ of assembling sentence structures might or might not be performed by the same cognitive mechanisms. Currently, the field of psycholinguistics implicitly adopts the position that they are supported by different cognitive mechanisms, as evident from the fact that most psycholinguistic models seek to explain either comprehension or production phenomena. The potential existence of two independent cognitive systems underlying linguistic performance doubles the problem of linking the theory of linguistic knowledge and the theory of linguistic performance, making the integration of linguistics and psycholinguistic harder. This thesis thus aims to unify the structure building system in comprehension, i.e., parser, and the structure building system in production, i.e., generator, into one, so that the linking theory between knowledge and performance can also be unified into one. I will discuss and unify both existing and new data pertaining to how structures are assembled in understanding and speaking, and attempt to show that the unification between parsing and generation is at least a plausible research enterprise. In Chapter 1, I will discuss the previous and current views on how parsing and generation are related to each other. I will outline the challenges for the current view that the parser and the generator are the same cognitive mechanism. This single system view is discussed and evaluated in the rest of the chapters. In Chapter 2, I will present new experimental evidence suggesting that the grain size of the pre-compiled structural units (henceforth simply structural units) is rather small, contrary to some models of sentence production. In particular, I will show that the internal structure of the verb phrase in a ditransitive sentence (e.g., The chef is donating the book to the monk) is not specified at the onset of speech, but is specified before the first internal argument (the book) needs to be uttered. I will also show that this timing of structural processes with respect to the verb phrase structure is earlier than the lexical processes of verb internal arguments. These two results in concert show that the size of structure building units in sentence production is rather small, contrary to some models of sentence production, yet structural processes still precede lexical processes. I argue that this view of generation resembles the widely accepted model of parsing that utilizes both top-down and bottom-up structure building procedures. In Chapter 3, I will present new experimental evidence suggesting that the structural representation strongly constrains the subsequent lexical processes. In particular, I will show that conceptually similar lexical items interfere with each other only when they share the same syntactic category in sentence production. The mechanism that I call syntactic gating, will be proposed, and this mechanism characterizes how the structural and lexical processes interact in generation. I will present two Event Related Potential (ERP) experiments that show that the lexical retrieval in (predictive) comprehension is also constrained by syntactic categories. I will argue that the syntactic gating mechanism is operative both in parsing and generation, and that the interaction between structural and lexical processes in both parsing and generation can be characterized in the same fashion. In Chapter 4, I will present a series of experiments examining the timing at which verbs’ lexical representations are planned in sentence production. It will be shown that verbs are planned before the articulation of their internal arguments, regardless of the target language (Japanese or English) and regardless of the sentence type (active object-initial sentence in Japanese, passive sentences in English, and unaccusative sentences in English). I will discuss how this result sheds light on the notion of incrementality in generation. In Chapter 5, I will synthesize the experimental findings presented in this thesis and in previous research to address the challenges to the single system view I outlined in Chapter 1. I will then conclude by presenting a preliminary single system model that can potentially capture both the key sentence comprehension and sentence production data without assuming distinct mechanisms for each.

Sinterização de Ce1-XEuXO2-(X/2) para aplicação como eletrólito sólido em células a combustível de temperaturas intermediárias

Given the environmental concern over global warming that occurs mainly by emission of CO2 from the combustion of petroleum, coal and natural gas research focused on alternative and clean energy generation has been intensified. Among these, the highlight the solid oxide fuel cell intermediate temperature (IT-SOFC). For application as electrolyte of the devices doped based CeO2 with rare earth ions (TR+ 3) have been quite promising because they have good ionic conductivity and operate at relatively low temperatures (500-800 ° C). In this work, studied the Ce1-xEuxO2-δ (x = 0,1, 0,2 and 0,3), solid solutions synthesized by the polymeric precursor method to be used as solid electrolyte. It was also studied the processing steps of these powders (milling, compaction and two step sintering) in order to obtain dense sintered pellets with reduced grain size and homogeneous microstructure. For this, the powders were characterized by thermal analysis, X-ray diffraction, particle size distribution and scanning electrons microscopy, since the sintered samples were characterized by dilatometry, scanning electrons microscopy, density and grain size measurements. By x-ray diffraction, it was verified the formation of the solid solution for all compositions. Crystallites in the nanometric scale were found for both sintering routes but the two step sintering presented significant reduction in the average grain size

Cold vapour generation electrothermal atomic absorption spectrometry and solid phase extraction based on a new nanosorbent for sensitive HG determination in environmental samples (sea water and river water)

Mercury is not an essential element for plant or animal life and it is a potential environmental toxic because of its tendency to form covalent bonds with organic molecules and the high stability of the Hg-C bond. Reports estimate a total mercury concentration in natural waters ranging from 0.2 to 100 ng L-1. Due to this fact, highly sensitive methods are required for direct determination of such extremely low levels. In this work, a rapid and simple method was developed for separation and preconcentration of mercury by flow injection solid phase extraction coupled with on-line chemical vapour generation electrothermal atomic absorption spectrometry. The system is based on chelating retention of the analyte onto the mini column filled with a mesoporous silica functionalized with 1,5 bis (di-2-pyridyl) methylene thiocarbohydrazide. The main aim of this work was to develop a precise and accurate method for the determination of the Hg. Under the optima conditions and 120 s preconcentration time, the detection limit obtained was 0.009 μg L-1, with RSDs 3.7 % for 0.2 μg L-1, 4.8 % for 1 μg L-1 and enrichment factor 4, Furthermore, the method proposed has permitted the determination of Hg with a reduction in the analysis time, the sample throughput was about 18 h-1, low consumption of reagents and sample volume. The method was applied to the determination of Hg in sea water and river water. For the quality control of the analytical performance and the validation of the newly developed method, the analysis of two certified samples, TMDA 54.4 Fortified Lake, and LGC6187 River sediment was addressed. The results showed good agreement with the certified values.

Development of water-soluble polyanionic carbosilane dendrimers as novel and highly potent topical anti-HIV-2 microbicides

This is the author’s version of a work that was accepted for publication in Nanoscale.

The Case for Teaching Culture through Neglected Authors: Carmen de Burgos and the Generation of '98

Teóricos del campo de la lingüística aplicada sostienen que para estudiantes de segunda lengua, la adquisición de la competencia cultural mejora por el uso de obras literarias. Aquí se propone que al integrar en la clase autores olvidados o marginados se ponen de relieve las ambigüedades, diferencias y contrastes presentes en la cultura predominante. Se ilustra cómo, en dos cuentos cortos de Carmen de Burgos, se plantea el problema de la mujer con todo lo complejo del tema, asunto casi pasado por alto por los autores incluidos en la Generación del '98.Applied linguistics theorists maintain that the acquisition of cultural competence by second-Ianguage students is enhanced through the use of literary works. The proposition of the present article is that by incorporating neglected or marginal authors i n the classroom, the ambiguities, differences and contrasts present in the predominant culture are highlighted. Through the study of two short stories by Carmen de Burgos, the woman question, a subject largely ignored by the Generation of 1898 writers, is set out in all of its complexity.

Behavioural outcomes of next-generation family members’ commitment to their firm

Are there variations in behaviours and leadership styles of next-generation family members or descendants who join their family business due to different forms of commitment? Evidence from a dual respondent study of 109 Canadian and Swiss family firms suggests that descendants with affective commitment to their family firms are more likely to engage in discretionary activities going beyond the job description, thereby contributing to organizational performance. Next-generation members with normative commitment are more likely to engage in transformational leadership behaviours. Both affectively and normatively motivated next-generation members use contingent reward forms of leadership. A surprising finding of this study is the binding force of normative commitment on positive leadership behaviours of next-generation members. This study empirically tests the generalizability of the three-component model of commitment to family businesses, a context in which different forms of commitment may play a unique role.

Relationship of joint deterioration with the generation of muscle strength in patients with hemophilic arthropathy. An observational study

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