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The kinetics of thermal degradation of ascorbic acid was studied in a Maltodextrin matrix at different temperatures between 75 and 140 °C. Isothermal experiments were performed with samples earlier equilibrated in environments of known aw at 4 °C, enclosed in hermetically sealed vials, with water contents (w) between 0.17 and 1.68 g water/g solids. Sampling times were selected according to an optimal experimental design in terms of minimum confidence regions of the parameters estimated, using the Bigelow model and estimates from preliminary experiments. The results showed a quadratic dependence of the reference D-value and linear dependence of the z-value with moisture content: Dr(140 °C) = 150.07 − 290.73w + 269w2 (min); z = 12.14 + 22.99w (°C) and showed the applicability of D-optimal designs for determining kinetic parameters in complex situations, with limited experimental requirements. The dependence of the rate constants with water content could not be described by the WLF model in qualitative terms, although in absolute values this model could be used with constants similar to those expected from glass transition theory. The thermodynamic analysis of the results showed a good application of the compensation theory in the whole range of water contents.

This paper shows how mathematical concepts can be displayed on World Wide Web pages. A few of the most interesting solutions are outlined although a few others are missing and a few more will be invented very soon. It is for authors to decide which system is the most suitable for their purposes.

Adsorption of wine proteins is an essential step in the production of white and rosé wines. In order to develop environmentally friendly adsorption processes, non-swelling adsorbents are required. The performance of selected non-swelling ion-exchange resins (Macro-Prep™ 50S and Streamline® SP) was studied by describing the process kinetics of the adsorption of BSA in a model wine solution. The process was assumed to be diffusion controlled and a shrinking core model was applied. Experiments were performed in the 5–35°C temperature range and with different equilibrium partition coefficients. The results obtained with the shrinking core model were theoretically consistent and the apparent diffusivity values correlated very well with theoretically estimated effective diffusivities combined with a linear dependence of porosity with temperature. Separating the temperature effect on porosity, the apparent diffusivity followed an Arrhenius type dependency with temperature with 16.9 kJ/mole activation energy.

The inactivation kinetics of horseradish peroxidase were determined at several values of pH (3, 4, 7, 9 and 10), temperature (40 to 70 °C) and pressure (7, 8 and 9 kbar). The data were obtained by taking samples from the moment that pressure inside the hydrostatic high pressure vessels reached the value specified, and therefore relate to isothermal and isobaric conditions. The inactivation kinetics were non‐log linear and could be individually well described by the conventional two‐fraction model, but the overall consistency of the kinetic parameters of this model was poor and the model was clearly not robust. Inversely, the kinetic model based on the Weibull probability distribution function yielded good individual fits and also a good overall consistency of the kinetic parameters. The whole set of 327 data points could be well described by an overall model considering that the shape parameter (ß) varied with pressure but not with temperature and that the rate parameter (1/α) varied with temperature according to an Arrhenius law, with a pressure‐independent activation energy, and varied exponentially with pressure. The activation energy and the pressure‐sensitivity parameter did not vary with pH up to pH 9. The results suggested a discontinuity of the kinetic behaviour at pH 10, with a different inactivation mechanism prevailing.

This work describes a method to study glass transition on native starch powders, based on dynamical mechanical thermal analysis using compression tests, and was applied to wheat flour (13.5% water content). This method will allow the determination of Tg in native (unprocessed) starchy materials, with minimal disturbance of the natural structures. The influence of the test conditions (heating rate, frequency and strain) on the glass transition measurements was determined using factorial designs. The values of Tg determined as the maxima of the energy dissipation (peaks in E″) of native flour and of freeze-dried pre-gelatinized flour were not statistically different (around 64 °C). The heating rate did not affect the measurements in the range tested (0.25 to 1 °C min−1). An interactive effect of the strain amplitude and the frequency was detected. The significance of this interaction can be caused by differences in mechanical energy dissipation, which would indicate that not only temperature but also the total energy input may affect this transition. Slight effects of phase separation between gluten and starch were found on native flour.

The protein adsorption capacity of different materials was evaluated to assess their potential efficacy as alternative adsorbents for the removal of proteins from wines, with the purpose of finding suitable low-swelling materials that could be used in a percolated bed. The adsorbents tested were thermally treated sodium bentonite, low-swelling adsorbing clays, ion exchange resins and other protein adsorbents (silica gel, hydroxyapatite and alumina). The materials were evaluated by analysing both the capacity to stabilize untreated white wines, according to a heat test, and by characterizing the adsorption isotherms of bovine serum albumin (BSA) in a model wine (water, ethanol and K-bitartrate). Breakthrough curves in a packed bed were determined experimentally for some materials, showing the influence of the adsorption isotherm shape. Some ion-exchange resins showed a favourable behaviour and have good potential as alternative adsorbents.

Employees are vital for enhancing customer satisfaction and loyalty in service organizations because their proactive involvement is an essential part of delivering the services offered. With the recent rapid growth of tourism in the Macau SAR, service employee workloads are clearly increasing, and consequently one would expect that the incidence of job burnout is rising. This study uses the well-known Maslach Burnout Inventory (MBI) to investigate the relationship between service employees' burnout and their willingness to deliver quality services. Self-administered questionnaires from 110 operational staff in three hotels in Macau have been analyzed. The results indicate that job burnout reduces staff's willingness to deliver quality services and that this effect is moderated by individual staff's level of affective organizational commitment, and their perceptions of the extent of organizational and supervisor support provided by the organization. Based on these results, practical managerial strategies to improve service performance are identified.

The importance of empowerment in service industries is recognized by practitioners and scholars in the West but there has been limited investigation of its impact on the willingness of service personnel in a high power-distance culture. This study examines how empowerment can be facilitated in the high power-distance context of China. Regression and path model analysis using a sample of 290 service employees from six 4-star to 5-star hotels in the Macau SAR China indicate that empowerment positively leads to higher service willingness and this relationship is mediated by performance-based rewards, and organizational and supervisor support. These findings have implications for HR managers considering or using empowerment.

Purpose – Given the diversity which exists among various groups of consumers, the purpose of this paper is to explore students' consumption of non‐alcoholic beverages in Nigeria. Design/methodology/approach – Three focus groups and 20 in‐depth interviews were conducted with students in three universities located in Lagos, Nigeria. Findings – Initial findings indicate that these students' consumption of non‐alcoholic beverages is influenced in many ways. Nevertheless, the most striking of these influences are found to be convenience of purchase, along with availability, price, health concerns, and culture/social reasons. Originality/value – The main contribution of the study lies in the relevance of segmentation, targeting, and positioning activities of business organisations in respect of marketing of non‐alcoholic beverages. Based on the findings, the empirical study will serve as a valuable input to marketers in their planning, analysis, and implementation of appropriate marketing strategies to students vis‐à‐vis the highlighted influences on their consumption of this category of food. It will thus serve as a tool for creating competitive advantage in this prevailing volatile business environment.

Use of CALMS to enrich learning in introductory programming courses

Complexities of Languages and Multilingualism

We critically review studies of subjective wellbeing conducted in China by the International Wellbeing Group, and we evaluate the International Wellbeing Index (IWI), a new instrument they developed. Subjective wellbeing was positive and similar in studies across China, and conformed to the normative range. Its resilience (PWI = 61.2–67.1) mirrors survey findings conducted in Western countries, in agreement with Subjective Wellbeing Homeostasis. Reliability, validity and psychometric analyses support the utility of the IWI as a measure of subjective wellbeing. Our conclusions have implications for research and social development in China, discussed further in this review.

This chapter explores Quality of Work Life (QWL) in Macau. We investigate the meanings and importance of QWL and its implications in terms of happiness and business performance. Although QWL is central to people’s lives, research on this topic is still in its infancy in Macau. Our interviews revealed three salient themes of QWL: Work context, the perceived benefits and demands of the job; Organization, mainly work environment and factors within the organizational context mediating QWL; and the implications of QWL on overall living and happiness.

In the Catholic world, the year 2017 is marked by the celebration of the 100th anniversary of the Apparitions of Mary in Fátima, Portugal. Although the field of the devotional and popular …

A interpretação da Escritura e das suas diferentes personagens enriquece a Tradição cristã, mas este processo de receção é muitas vezes marcado por debates e polémica …

This dissertation is a comprehensive academic examination of the characteristics and complex historical progress within the Pentecostal and Charismatic Movement in Macau Protestant Churches. Since Macau hosted the first Pentecostal and Charismatic missionary, Thomas J. McIntosh, who entered China in 1907, the history of the Pentecostal and Charismatic Movement in Macau lacks a consistent and synthesized research until now. Thus, primary and secondary resources have been analyzed and reconstructed and historically interpreted to gain a better and deeper understanding of the emergence and development of the Pentecostal and Charismatic Movement within Macau’s Protestant Churches from the beginning up to the present day. This academic review makes an important contribution to Macau with respect to its historical development and will fill the gap in knowledge within the Global church history of the Pentecostal and Charismatic Movement. Key Words: Charismatic, Christianity in China, History of Missionaries in China, Macao, Macau, Pentecostalism, Protestant, T. J. McIntosh

This dissertation is an attempt to analyze the twelve selected dreams written or reviewed by St. John Bosco in order to present the notion of an exemplary Salesian. These dreams inspired Don Bosco’s vocation, charism, and dealing with his life’s contingencies and correlate with his pastoral ministry for youth under the social-ecclesiastical context of the nineteenth century. The methodology for this research consists of two approaches: an investigation of their spiritual theology, and Morton T. Kelsey’s approach. In the first part, five dimensions of spiritual theology are explored: (1) the conformity to the truth, (2) the humility and the docility to the Divine will, (3) the discretion and the gravity of seeking the glory of God, (4) the liberty of Spirit with joy, and (5) the guidance of the Spirit. In the latter part, three issues inspired by Kelsey are explored: (1) the personal issue, including the exploration of thought and feeling; (2) the correlation between the dream content and the reality, including images and archetypal symbols associated with experience and memory; (3) the spiritual issue, including one’s openness to God and relation with Him. Through this present research, a model of an exemplary Salesian has been conceptualized, which considers three virtues: health, wisdom, and sanctity. This present study is expected to be beneficial to enhance the faithful’s spirituality. Moreover it is hoped it will provide a healthy stimulus for Salesians to seek to live an excellent Salesian religious life, and to the faithful be devoted Christians in this world as well for the sake of glorifying the Divine mercy

The issue of religious freedom affects Sino-Vatican relations, but the Roman Catholic Church shares values with Confucianism, which provides common ground for dialogue. Pope Francis is focusing the church outward by promoting a culture of encounter and by working unceasingly for a fraternal dialogue of peace. Chinese president Xi Jinping urges his people to fulfill the China dream, emphasizing the core values of harmony, friendship, and civilization. Many have believed that the Gospel can contribute to China?s spiritual civilization; normalization of relations between China and the Holy See would benefit China and the Catholic Church and contribute to world peace and harmony.