Multiphase porous media model for Intermittent Microwave Convective Drying (IMCD) of food

Intermittent microwave convective (IMCD) drying is an advanced drying technology that improves both energy efficiency and food quality during the drying of food materials. Despite numerous experimental studies available for IMCD, there is no complete multiphase porous media model available to describe the process. A multiphase porous media model considering liquid water, gases and the solid matrix inside the food during drying can provide in depth understanding of IMCD. In this article, firstly a multiphase porous media model was developed for IMCD. Then the model is validated against experimental data by comparing moisture content and temperature distributions after each heating and tempering periods. The profile of vapour pressures and evaporation during IMCD are presented and discussed. The relative contribution of water and vapour fluxes due to gas pressure and diffusion demonstrated that the fluxes due are relatively higher in IMCD compared to convection drying and this makes the IMCD faster.

Mitochondrial helicase Twinkle in mtDNA copy number regulation and a late-onset disease model

Mitochondrial diseases are caused by disturbances of the energy metabolism. The disorders range from severe childhood neurological diseases to muscle diseases of adults. Recently, mitochondrial dysfunction has also been found in Parkinson s disease, diabetes, certain types of cancer and premature aging. Mitochondria are the power plants of the cell but they also participate in the regulation of cell growth, signaling and cell death. Mitochondria have their own genetic material, mtDNA, which contains the genetic instructions for cellular respiration. Single cell may host thousands of mitochondria and several mtDNA molecules may reside inside single mitochondrion. All proteins needed for mtDNA maintenance are, however, encoded by the nuclear genome, and therefore, mutations of the corresponding genes can also cause mitochondrial disease. We have here studied the function of mitochondrial helicase Twinkle. Our research group has previously identified nuclear Twinkle gene mutations underlying an inherited adult-onset disorder, progressive external ophthalmoplegia (PEO). Characteristic for the PEO disease is the accumulation of multiple mtDNA deletions in tissues such as the muscle and brain. In this study, we have shown that Twinkle helicase is essential for mtDNA maintenance and that it is capable of regulating mtDNA copy number. Our results support the role of Twinkle as the mtDNA replication helicase. No cure is available for mitochondrial disease. Good disease models are needed for studies of the cause of disease and its progression and for treatment trials. Such disease model, which replicates the key features of the PEO disease, has been generated in this study. The model allows for careful inspection of how Twinkle mutations lead to mtDNA deletions and further causes the PEO disease. This model will be utilized in a range of studies addressing the delay of the disease onset and progression and in subsequent treatment trials. In conclusion, in this thesis fundamental knowledge of the function of the mitochondrial helicase Twinkle was gained. In addition, the first model for adult-onset mitochondrial disease was generated.

Thrombin regulation in newborn infants

The coagulation system of newborn infants differs markedly from that of older children and adults. The activities of most coagulation factors and anticoagulants are low, leading to altered regulation in the formation of the key enzyme, thrombin. Timely and adequate generation of thrombin is essential, as thrombin activates platelets and many coagulation factors, cleaves fibrinogen into fibrin and activates the antithrombotic and anti-inflammatory protein C pathway. On the other hand, excess thrombin may promote thrombotic complications and exacerbate harmful inflammatory reactions. Despite the characteristic features, the newborn coagulation system can be considered physiological, since healthy newborns rarely show haemorrhagic or thrombotic complications. Sick newborns, however, often encounter clinical situations that challenge their coagulation system. The aim of this study was to clarify the behaviour of the neonatal coagulation system in selected clinical situations, with a special emphasis on the generation of thrombin. Thrombin was measured by in vivo thrombin generation markers and by thrombin generation potential in vitro. The patient groups included sick newborns undergoing intensive care and receiving fresh-frozen plasma (FFP), requiring exchange transfusions (ET) or presenting with a congenital heart defect requiring open heart surgery. Additionally, healthy newborns with inherited heterozygous factor V Leiden (FVL) mutation were studied. Thrombin generation potential was also analysed in cord plasma of healthy infants and in adults. Healthy as well as sick newborn infants showed lower total thrombin generation potential in vitro but faster initiation of thrombin generation than adults. These findings were qualitatively similar when plasma was supplemented with platelets. Platelets, however, significantly altered the effect of the major anticoagulant, activated protein C (APC), on thrombin generation potential. In accordance with previous studies, thrombin generation in healthy newborn platelet-poor plasma was resistant to the anticoagulant effects of APC, but when the plasma was supplemented with platelets APC attenuated thrombin generation significantly more in newborns than in adults. In vivo generation of thrombin was elevated in nearly all of the sick newborn infants. The low-volume FFP transfusion as opposed to the change from neonatal to adult blood in ET exerted markedly different effects on neonatal thrombin generation. FFP reduced the in vivo generation of thrombin in those newborns with the highest pretransfusional thrombin generation, thus acting as an anticoagulant agent. In those infants with lower pretransfusional thrombin generation, the effect of FFP on thrombin generation was fairly neutral. On the other hand, the combination of red blood cells and FFP, used to perform ET, significantly increased the in vivo thrombin formation and shifted the balance in the newborn coagulation system to the procoagulant direction. Cardiopulmonary bypass (CPB) also significantly increased the in vivo thrombin generation, but the thrombin generation profile during CPB differed from that previously observed in adults. Escalation of thrombin at early reperfusion was not observed in newborns; in adults, its occurrence is associated with postoperative myocardial damage. Finally, in healthy newborns with FVL heterozygosity, faster initiation of thrombin generation was observed compared with controls. Interestingly, FV level was lower in FVL-heterozygous infants, possibly to counteract the procoagulant effects induced by FVL. In conclusion, unique features regarding thrombin regulation in newborn infants were observed. These features included a novel platelet effect on the regulation of the protein C pathway. The clinical challenges mainly seemed to shift the balance in the coagulation system of newborns to the procoagulant direction. Blood component transfusions markedly affected coagulation in a manner specific to the product but that could also be altered by the clinical situation. Overall, the results highlight the need for understanding developmental haemostasis for both diagnostic and therapeutic purposes.

Introduction: Food literacy for contemporary food and eating

This chapter provides an introduction to the term “food literacy”. Its use in the literature, policy and practice, implies that the term is an attempt to encapsulate the knowledge, skills and behaviours needed for everyday eating. This chapter will first review the use of the term in policy and practice, then go on to review what is known about contemporary food and eating and its influence on the emergence of this term and conclude with an overview of the key ideas to be explored in this book.

An overview of the use of the term food literacy

This chapter examines the history and breadth of use of the term “food literacy” in scholarly literature. It reviews and compares various popularly used definitions from diverse paradigms. Other terms such as “cooking”, “food skills” and “food wellbeing” used to describe the everyday knowledge, skills and behaviours used to meet food needs are also examined.

A definition of food literacy and its components

This chapter defines food literacy and its components using the empirical data collected in two studies undertaken in 2010 and 2011 as part of the author’s PhD thesis. The first was a Delphi study of Australian food experts and the second was a study of young adults across a spectrum of disadvantage. Defining food literacy and identifying its components was an iterative process. At different times throughout the research, each study informed the other. This chapter will describe the components of food literacy, the data used to identify them and how they combined to produce a definition of food literacy.

Relating food literacy to nutrition and health

This chapter describes the evolution of a model to propose the relationship between food literacy and nutrition. This model can also be used as a framework for program planning, implementation and evaluation. Practitioners and policy makers invest in food literacy with outcome expectations beyond diet quality. For this reason, a second model was developed to conceptualise the role of food literacy with respect to food security, body weight and chronic disease risk. This second model is useful in positioning food literacy within multi-strategic public health nutrition and chronic disease plans.

The development of food literacy

This is the first of four chapters examining the development of food literacy. It reports the findings of the Young People Study, described in earlier chapters. Participants reflected on the evolution of their food and eating style. They describe this at the individual level but in doing so discuss the interplay between other key institutions of health, education and community organisations. These results are considered alongside learning and development theory to propose how food literacy develops, including the role of individuals, households, communities and nations, and their influence to each other.

Food literacy: Key concepts and the elephants in the room

This chapter summarizes the content of this book. It identifies key issues that require further investigation and development. It re-enforces key concepts.

Food Literacy: Key Concepts for Health and Education

Globally, the food system and the relationship of the individual to that system, continues to change and grow in complexity. Eating is an everyday event that is part of everyone’s lives. There are many commentaries on the nature of these changes to what, where and how we eat and their socio-cultural, environmental, educational, economic and health consequences. Among this discussion, the term "food literacy" has emerged to acknowledge the broad role food and eating play in our lives and the empowerment that comes from meeting food needs well. In this book, contributors from Australia, China, United Kingdom and North America provide a review of international research on food literacy and how this can be applied in schools, health care settings and public education and communication at the individual, group and population level. These varying perspectives will give the reader an introduction to this emerging concept. The book gathers current insights and provides a platform for discussion to further understanding and application in this field. It stimulates the reader to conceptualise what food literacy means to their practice and to critically review its potential contribution to a range of outcomes.