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The on-board identification of ore minerals during a cruise is often postponed until long after the cruise is over. During the M127 cruise, 21 cores with deep-seafloor sediments were recovered in the Trans-Atlantic Geotraverse (TAG) field along the Mid Atlantic Ridge (MAR). Sediments were analyzed on-board for physicochemical properties such as lightness (L*), pH and Eh. Selected samples were studied for mineral composition by X-ray powder diffraction (XRD). Based on XRD data, sediment samples were separated into high-, low- and non-carbonated. Removal of carbonates is a common technique in mineralogical studies in which HCl is used as the extraction agent. In the present study, sequential extraction was performed with sodium acetate buffer (pH 5.0) to remove carbonates. The ratio between the highest calcite XRD reflection in the original samples (Iorig) vs its XRD-reflection in samples after their treatment with the buffer (Itreat) was used as a quantitative parameter of calcite removal, as well as to identify minor minerals in carbonated samples (when Iorig/Itreat > 24). It was found that the lightness parameter (L*) showed a positive correlation with calcite XRD reflection in selected TAG samples, and this could be applied to the preliminary on-board determination of extraction steps with acetate buffer (pH 5.0) in carbonated sediment samples. The most abundant minerals detected in carbonated samples were quartz and Al- and Fe-rich clays. Other silicates were also detected (e.g., calcic plagioclase, montmorillonite, nontronite). In non-carbonated samples, Fe oxides and hydroxides (goethite and hematite, respectively) were detected. Pyrite was the dominant hydrothermal mineral and Cu sulfides (chalcopyrite, covellite) and hydrothermal Mn oxides (birnessite and todorokite) were mineral phases identified in few samples, whereas paratacamite was detected in the top 20 cm of the core. The present study demonstrates that portable XRD analysis makes it possible to characterize mineralogy at cored sites, in particular in both low- and high-carbonated samples, before the end of most cruises, thus enabling the quick modification of exploration strategies in light of new information as it becomes available in near-real time.

The following study reflects and explores the dynamics of aesthetic experiences within drama improvisations. This arts-based research was carried out in Hong Kong with six Cantonese children who were aged 3?5?years. Data were collected from the video transcripts of five workshops and the researcher?s own research journal. Two significant milieus were observed: switching in-between roles and intuitive creativity is not talkback. I argue that because each of these two milieus provide the foreground for the complex ? and at times contradictory ? nature of children?s aesthetic experiences where Deleuzian power is at play, opportunities arise for both, challenging the traditional adult?child power relations, and in so doing, educators can be able to reconfigure and reconceptualise teaching goals and practices, both generally and specifically, within the context of early childhood education.

Validation of the Teachers’ Sense of Efficacy Scale (TSES) for use with teachers in Macao (SAR) was undertaken to determine its usefulness as a measure of teacher self-efficacy for inclusive education. This paper discusses the results found by analyzing various versions of the TSES and TSES-C in a Chinese format with 200 pre-service teachers in Macao (SAR).  Psychometric analyses were undertaken to investigate the validity of the existing scales and the three and two factor solutions. The results indicated a preferred 9-item version that produced improved factor loadings and reliabilities. The use of a relatively quick and short scale to measure such a complex phenomenon as teacher self-efficacy is discussed. Issues are raised regarding generalizability of scales and the impact of culture, demographics, and edifying issues that may impact on the usefulness of such scales.

Hyper-consumption in capitalist economies has had a severe impact on the environment that no one can escape. In recent year, there has been a high degree of optimism in sharing economy with regard to coping with the environmental problems caused by consumption. However, most of the current literature focuses on business perspectives in which a sharing economy is portrayed as a new business model, but not as a way to curb environmental degradation. This paper, based on a social science perspective, investigates the potentials and limitations of the strategies adopted in sharing economy projects towards social transformation (especially coping with environmental degradation and hyper-consumption), with the adoption of Erik Olin Wright’s concept of real utopia. A case study approach has been adopted in terms of a sharing economy project named ‘Waste-no-mall (Yuen Long)’ in Hong Kong. The project founder embraces ideological-led strategies based on collective responsibility, self-determination and reflexivity, encouraging the participants to reflect on their consumption behaviours, and thus increasing the level of awareness of the need to reduce unnecessary consumption. However, it is a double-edge sword that limits its impact to those who are active participants, without spreading to others the need for change. It is also limited for their interstitial strategies within the project, and is unable to call for a concrete symbiotic transformation when it comes to policy. The significance of this paper is two-fold. First, it adopts a social science perspective that centres on exploring the proclaimed social implications of sharing economy, an aspect which is under-studied given that most of current studies are from a business perspective; second, it extends Wright’s concept to an operational level by showing an important pathway aiming to solve environmental problems through the simultaneous achievement of both horizontal and vertical balancing strategies, based on Wright’s concept of real utopia.

Mangroves are a unique group of plants, which offer a great variety of goods and services to the ecosystem and to the society. Regrettably, they have been globally threatened by urbanization and industrialization, among others, triggering overexploitation of the world’s mangrove forests despite their ecological and economic importance. As a result, mangroves are often under pollution stress as sinks or receivers for numerous man-made pollutants such as pesticides, which are the main focus of this thesis. One of the most widely applied chemicals in the word are the organochlorine pesticides (OCPs) that even after their supposedly worldwide ban between 1950s-1990s, they can still be detected in the environment. Numerous studies have been done in phytoremediation of pollutants by mangroves, but little attention has been given to the role of mangroves in the remediation of OCPs. For this reason, part of this thesis will focus on the occurrence and distribution of OCPs in intertidal tropical and sub-tropical areas around the world with and without mangroves. As a first goal (I), we evaluate —in a theoretical way— if the presence of mangroves affects or modifies the levels of OCPs in the surrounding environment. For this purpose, data from different matrices, such as water, sediment, benthic fauna and plants were included and discussed in this work. Moreover, and considering Macao’s location, we also quantified OCPs from surface waters of this region from areas with and without mangroves and included in this task. Besides this theoretical approach, this thesis also included some laboratoy and field work specifically focused on dicofol and 4,4’-dichlorobenzophenone (4,4’-DCBP, its main metabolite). Dicofol is an OCP strongly related to dichlorodiphenyltrichloroethane (DDT), which has been extensively used in China and more specifically, in the Pearl River Delta (PRD), a region under anthropogenic pressure. However, due to dicofol’s instability (i.e., sensitive to low pH, light exposure and high temperature), we expected to quantify 4,4′-DCBP (which is also common to DDT) as the main form present in the environment. As a second goal (II), we conducted a monitoring study in surface waters from Macao and Hong Kong, to evaluate the contamination status and water quality of these regions. Concentrations of 4,4’-DCBP, nutrients and physicochemical parameters were measured during transition and wet season, and at high and low tide. In addition, since the toxicity of this metabolite was totally unknown, we assessed it via two biological models: Daphnia magna and Artemia salina. Since 4,4’-DCBP was detected and quantified in both regions (2.8-30.0 ng/L), this thesis also includes experimental work focused on the assimilation and depuration pattern by a marine organism. For that purpose and as a final goal (III), we selected the common edible bivalve Meretrix as a model to evaluate the dynamics of accumulation and depuration of the pesticide dicofol. The Vietnamese clams were exposed during 15 days under two different concentrations of dicofol, and decontaminated for the same period of time. Quantification of 4,4’-DCBP was done during both phases (uptake and depuration) and at different sampling times. In summary, all these different works helped us to conclude that: I.1) As expected, vegetated areas with mangroves presented lower concentrations of OCPs for all the matrices, and also better quality in terms of pesticide pollution for water and sediments. Results obtained from Macao’s waters also revealed the same pattern, with mangroves areas having lower levels of contamination. Although the gathered data presented methodological variability (i.e. different quantification methods, extraction protocols, equipment used), the same pattern was observed among matrices, showing how robust and solid the results herein obtained are. II.1). Hong Kong presented higher concentrations of 4,4’-DCBP than Macao, which may be due to the use of dicofol as a pesticide and the use of antifouling-paint for ships. Moreover, concentrations of 4,4’-DCBP during wet season were below limits of quantification, demonstrating a seasonal pattern and a dilution effect due to higher river discharges during this period. II.2). Both regions showed possible eutrophication problems due to the high nutrient concentrations. These levels presented also a seasonal variability, with dissolved inorganic nitrogen and total dissolved solids higher during transition; and dissolved inorganic phosphorous, total suspended solids and chlorophyll a higher during wet season. II.3). Toxicity of 4,4’-DCBP was lower than the parent compound dicofol, and the levels quantified indicated a low environmental risk. However, it is important to pay attention to this compound since interaction with other contaminants could enhance their toxicity, or processes such as biomagnification or bioaccumulation could make low concentrations a threat for the environment. III.1). Different concentrations of dicofol presented different uptake and depuration kinetics. Animals exposed to higher concentrations (500 ng/L), had levels above limits of quantification (LOQ) after 24h exposure, unlike the ones exposed to lower concentrations (50 ng/L), which had levels <LOQ after the same period. The first ones also, presented lower uptake rates, and this could indicate that high dicofol concentrations in the system could affect the respiration rates of the organism. In addition, this work also showed that animals exposed to high concentrations of dicofol will need more than 15 days to depurate in order to reach safe levels for human consumption. The compilation of the work done in this thesis allowed us to better understand the role of mangroves ecosystems on the accumulation of OCPs and to provide solid information that could create strategies for mangroves management and conservation. Moreover, and as a first attempt, we were able to quantify this pesticide metabolite in the PRD (one of the most seriously contaminated areas in China), to determine its toxicity and to define its kinetics in an important organism such as the edible bivalve M. meretrix. We intend that this thesis will be helpful for the scientific community providing new insights regarding metabolite interactions (within and with other molecules) and toxicity (LC50 and theoretical risk assessment), which were unknown until now

This book is a compilation of the best papers presented at the APEF 2019 conference which was held on 25th and 26th July 2019 at the Grand Copthorne Waterfront in Singapore. With a great number of submissions, it presents the latest research findings in economics and finance and discusses relevant issues in today's world. The book is a useful resource for readers who want access to economics, finance and business research focusing on the Asia-Pacific region.