10 resultados para functional feeding group

em CORA - Cork Open Research Archive - University College Cork - Ireland


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Strategic reviews of the Irish Food and Beverage Industry have consistently emphasised the need for food and beverage firms to improve their innovation and marketing capabilities, in order to maintain competitiveness in both domestic and overseas markets. In particular, the functional food and beverages market has been singled out as an extremely important emerging market, which Irish firms could benefit from through an increased technological and market orientation. Although health and wellness have been the most significant drivers of new product development (NPD) in recent years, failure rates for new functional foods and beverages have been reportedly high. In that context, researchers in the US, UK, Denmark and Ireland have reported a marked divergence between NPD practices within food and beverage firms and normative advice for successful product development. The high reported failure rates for new functional foods and beverages suggest a failure to manage customer knowledge effectively, as well as a lack of knowledge management between functional disciplines involved in the NPD process. This research explored the concept of managing customer knowledge at the early stages of the NPD process, and applied it to the development of a range of functional beverages, through the use of advanced concept optimisation research techniques, which provided for a more market-oriented approach to new food product development. A sequential exploratory research design strategy using mixed research methods was chosen for this study. First, the qualitative element of this research investigated customers’ choice motives for orange juice and soft drinks, and explored their attitudes and perceptions towards a range of new functional beverage concepts through a combination of 15 in-depth interviews and 3 focus groups. Second, the quantitative element of this research consisted of 3 conjoint-based questionnaires administered to 400 different customers in each study in order to model their purchase preferences for chilled nutrient-enriched and probiotic orange juices, and stimulant soft drinks. The in-depth interviews identified the key product design attributes that influenced customers’ choice motives for orange juice. The focus group discussions revealed that groups of customers were negative towards the addition of certain functional ingredients to natural foods and beverages. K-means cluster analysis was used to quantitatively identify segments of customers with similar preferences for chilled nutrient-enriched and probiotic orange juices, and stimulant soft drinks. Overall, advanced concept optimisation research methods facilitate the integration of the customer at the early stages of the NPD process, which promotes a multi-disciplinary approach to new food product design. This research illustrated how advanced concept optimisation research methods could contribute towards effective and efficient knowledge management in the new food product development process.

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Thin film dielectrics based on titanium, zirconium or hafnium oxides are being introduced to increase the permittivity of insulating layers in transistors for micro/nanoelectronics and memory devices. Atomic layer deposition (ALD) is the process of choice for fabricating these films, as it allows for high control of composition and thickness in thin, conformal films which can be deposited on substrates with high aspect-ratio features. The success of this method depends crucially on the chemical properties of the precursor molecules. A successful ALD precursor should be volatile, stable in the gas-phase, but reactive on the substrate and growing surface, leading to inert by-products. In recent years, many different ALD precursors for metal oxides have been developed, but many of them suffer from low thermal stability. Much promise is shown by group 4 metal precursors that contain cyclopentadienyl (Cp = C5H5-xRx) ligands. One of the main advantages of Cp precursors is their thermal stability. In this work ab initio calculations were carried out at the level of density functional theory (DFT) on a range of heteroleptic metallocenes [M(Cp)4-n(L)n], M = Hf/Zr/Ti, L = Me and OMe, in order to find mechanistic reasons for their observed behaviour during ALD. Based on optimized monomer structures, reactivity is analyzed with respect to ligand elimination. The order in which different ligands are eliminated during ALD follows their energetics which was in agreement with experimental measurements. Titanocene-derived precursors, TiCp*(OMe)3, do not yield TiO2 films in atomic layer deposition (ALD) with water, while Ti(OMe)4 does. DFT was used to model the ALD reaction sequence and find the reason for the difference in growth behaviour. Both precursors adsorb initially via hydrogen-bonding. The simulations reveal that the Cp* ligand of TiCp*(OMe)3 lowers the Lewis acidity of the Ti centre and prevents its coordination to surface O (densification) during both of the ALD pulses. Blocking this step hindered further ALD reactions and for that reason no ALD growth is observed from TiCp*(OMe)3 and water. The thermal stability in the gas phase of Ti, Zr and Hf precursors that contain cyclopentadienyl ligands was also considered. The reaction that was found using DFT is an intramolecular α-H transfer that produces an alkylidene complex. The analysis shows that thermal stabilities of complexes of the type MCp2(CH3)2 increase down group 4 (M = Ti, Zr and Hf) due to an increase in the HOMO-LUMO band gap of the reactants, which itself increases with the electrophilicity of the metal. The reverse reaction of α-hydrogen abstraction in ZrCp2Me2 is 1,2-addition reaction of a C-H bond to a Zr=C bond. The same mechanism is investigated to determine if it operates for 1,2 addition of the tBu C-H across Hf=N in a corresponding Hf dimer complex. The aim of this work is to understand orbital interactions, how bonds break and how new bonds form, and in what state hydrogen is transferred during the reaction. Calculations reveal two synchronous and concerted electron transfers within a four-membered cyclic transition state in the plane between the cyclopentadienyl rings, one π(M=X)-to-σ(M-C) involving metal d orbitals and the other σ(C-H)-to-σ(X-H) mediating the transfer of neutral H, where X = C or N. The reaction of the hafnium dimer complex with CO that was studied for the purpose of understanding C-H bond activation has another interesting application, namely the cleavage of an N-N bond and resulting N-C bond formation. Analysis of the orbital plots reveals repulsion between the occupied orbitals on CO and the N-N unit where CO approaches along the N-N axis. The repulsions along the N-N axis are minimized by instead forming an asymmetrical intermediate in which CO first coordinates to one Hf and then to N. This breaks the symmetry of the N-N unit and the resultant mixing of MOs allows σ(NN) to be polarized, localizing electrons on the more distant N. This allowed σ(CO) and π(CO) donation to N and back-donation of π*(Hf2N2) to CO. Improved understanding of the chemistry of metal complexes can be gained from atomic-scale modelling and this provides valuable information for the design of new ALD precursors. The information gained from the model decomposition pathway can be additionally used to understand the chemistry of molecules in the ALD process as well as in catalytic systems.

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In this work, the properties of strained tetrahedrally bonded materials are explored theoretically, with special focus on group-III nitrides. In order to do so, a multiscale approach is taken: accurate quantitative calculations of material properties are carried out in a quantum first-principles frame, for small systems. These properties are then extrapolated and empirical methods are employed to make predictions for larger systems, such as alloys or nanostructures. We focus our attention on elasticity and electric polarization in semiconductors. These quantities serve as input for the calculation of the optoelectronic properties of these systems. Regarding the methods employed, our first-principles calculations use highly- accurate density functional theory (DFT) within both standard Kohn-Sham and generalized (hybrid functional) Kohn-Sham approaches. We have developed our own empirical methods, including valence force field (VFF) and a point-dipole model for the calculation of local polarization and local polarization potential. Our local polarization model gives insight for the first time to local fluctuations of the electric polarization at an atomistic level. At the continuum level, we have studied composition-engineering optimization of nitride nanostructures for built-in electrostatic field reduction, and have developed a highly efficient hybrid analytical-numerical staggered-grid computational implementation of continuum elasticity theory, that is used to treat larger systems, such as quantum dots.

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Vascular smooth muscle cells (VSMC) are one of the key players in the pathogenesis of cardiovascular diseases. The origin of neointimal VSMC has thus become a prime focus of research. VSMC originate from multiple progenitors cell types. In embryo the well-defined sources of VSMC include; neural crest cells, proepicardial cells and EPC. In adults, though progenitor cells from bone marrow (BM), circulation and tissues giving rise to SMC have been identified, no progress has been made in terms of isolating highly proliferative clonal population of adult stem cells with potential to differentiate into SMC. Smooth muscle like stem progenitor cells (SMSPC) were isolated from cardiopulmonary bypass filters of adult patients undergoing CABG. Rat SMSPC have previously been isolated by our group from the bone marrow of Fischer rats and also from the peripheral blood of monocrotaline induced pulmonary hypertension (MCT-PHTN) animal model. Characterization of novel SMSPC exhibited stem cell characteristics and machinery for differentiation into SMC. The expression of Isl-1 on SMSPC provided unique molecular identity to these circulating stem progenitor cells. The functional potential of SMSPC was determined by monitoring adoptive transfer of GFP+ SMSPC in rodent models of vascular injury; carotid injury and MCT-PHTN. The participation of SMSPC in vascular pathology was confirmed by quantifying the peripheral blood, and engrafted levels of SMSPC using RT-PCR. In terms of translating into clinical practice, SMSPC could be a good tool for detecting the atherosclerotic plaque burden. The current study demonstrates the existence of novel adult stem progenitor cells in circulation, with the potential role in vascular pathology.

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Using C57BL/6J mice fed whey protein isolate (WPI) enriched high fat (HFD) or low-fat diets (LFD), this study tested the hypothesis that WPI directly impacts on adiposity by influencing lipid metabolism. WPI suppressed HFD-induced body fat and increased lean mass at 8 weeks of dietary challenge despite elevated plasma triacylglycerol (TAG) levels, suggesting reduced TAG storage. WPI reduced HFD-associated hypothalamic leptin and insulin receptor (IR) mRNA expression, and prevented HFD-associated reductions in adipose tissue IR and glucose transporter 4 expression. These effects were largely absent at 21 weeks of HFD feeding, however WPI increased lean mass and cause a trend towards decreased fat mass, with notable increased Lactobacillus and decreased Clostridium gut bacterial species. Increasing the protein to carbohydrate ratio enhanced the above effects, and shifted the gut microbiota composition away from the HFD group. Seven weeks of WPI intake with a LFD decreased insulin signalling gene expression in the adipose tissue in association with an increased fat accumulation. WPI reduced intestinal weight and length, suggesting a potential functional relationship between WPI, gastro-intestinal morphology and insulin related signalling in the adipose. Extending the study to 15 weeks, did not affect adipose fat weight, but decreased energy intake, weight gain and intestinal length. The functionality of protein sensing lysophosphatidic acid receptor 5 (LPA5) in 3T3-L1 pre-adipocytes was assessed. Over-expression of the receptor in 3T3-L1 pre-adipocytes provided a growth advantage to the cells and suppressed cellular differentiation into mature fat cells. In conclusion, the data demonstrates WPI impacts on adiposity by influencing lipid metabolism in a temporal manner, resulting possibly due to changes in lean mass, hypothalamic and adipose gene expression, gut microbiota and gastrointestinal morphology. The data also showed LPA5 is a novel candidate in regulating of preadipocyte growth and differentiation, and may mediate dietary protein effects on adipose tissue.

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Group IV materials such as silicon nanocrystals (Si NCs) and carbon quantum dots (CQDs) have received great attention as new functional materials with unique physical/chemical properties that are not found in the bulk material. This thesis reports the synthesis and characterisation of both types of nanocrystal and their application as fluorescence probes for the detection of metal ions. In chapter 2, a simple method is described for the size controlled synthesis of Si NCs within inverse micelles having well defined core diameters ranging from 2 to 6 nm using inert atmospheric synthetic methods. In addition, ligands with different molecular structures were utilised to reduce inter-nanocrystal attraction forces and improve the stability of the NC dispersions in water and a variety of organic solvents. Regulation of the Si NCs size is achieved by variation of the surfactants and addition rates, resulting high quality NCs with standard deviations (σ = Δd/d) of less than 10 %. Large scale production of highly mondisperse Si NC was also successfully demonstrated. In chapter 3, a simple solution phase synthesis of size monodisperse carbon quantum dots (CQDs) using a room temperature microemulsion strategy is demonstrated. The CQDs are synthesized in reverse micelles via the reduction of carbon tetrachloride using a hydride reducing agent. CQDs may be functionalised with covalently attached alkyl or amine monolayers, rendering the CQDs dispersible in wide range of polar or non-polar solvents. Regulation of the CQDs size was achieved by utilizing hydride reducing agents of different strengths. The CQDs possess a high photoluminescence quantum yield in the visible region and exhibit excellent photostability. In chapter 4, a simple and rapid assay for detection of Fe3+ ions was developed, based on quenching of the strong blue-green Si NC photoluminescence. The detection method showed a high selectivity, with only Fe3+ resulting in strong quenching of the fluorescence signal. No quenching of the fluorescence signal was induced by Fe2+ ions, allowing for solution phase discrimination between the same ion in different charge states. The optimised sensor system showed a sensitive detection range from 25- 900 μM and a limit of detection of 20.8 μM

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The work presented in this dissertation focused on the development and characterisation of novel cocrystals that incorporated the thioamide, amide and imide functional groups. A particular emphasis was placed on the characterisation of these cocrystals by single crystal X-ray diffraction methods. In Chapter One a summary of the intermolecular interactions utilised in this work and a short review of the solid state and multicomponent systems is provided. A brief introduction to the ways in which different multicomponent systems can be distinguished, crystal engineering strategies and a number of cocrystal applications highlights the importance the understanding of intermolecular interactions can have on the physical and chemical properties of crystalline materials. Chapter Two is the first Results and Discussion chapter and includes an introduction that is specific to the chapter. The main body of this work focuses on the primary aromatic thioamide functional group and its propensity to cocrystallise with a number of sulfoxides. Unlike the amide functional group, thioamides are not commonly employed in cocrystallisation studies. This chapter presents the first direct comparison between the cocrystallisation abilities of these two functional groups and the intermolecular hydrogen bonding interactions present in the cocrystal structures are examined. Chapter Three describes the crystal landscape of a short series of secondary aromatic amides and their analogous thioamides. Building on the results obtained in Chapter Two, a cocrystal screen of the secondary thioamides with the sulfoxide functional group was carried out in order to determine the effect removing a hydrogen bond had on the supramolecular synthons observed in the cocrystals. These secondary thioamides are also utilised in Chapter Four, which examines their halogen bonding capabilities with two organoiodine coformers: 1,2- and 1,4-diiodotetrafluorobenzene. Chapter Five explores the cocrystallisation abilities of three related cyclic imides as coformers for cocrystallisation with a range of commonly used coformers. Chapter Six is an overall conclusions chapter that highlights the findings of the results presented in Chapters Two to Five. Chapter Seven details the instrument and experimental data for the compounds and cocrystals discussed in the Results and Discussion Chapters. The accompanying CD contains all of the crystallographic data in .cif format for the novel single crystal structures characterised in this work.

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The aim of this study was to explore symptom burden and its relationship to functional performance in patients with COPD. A descriptive, cross-sectional, correlational survey design was used and a sample of 214 patients with COPD. The sample was recruited from patients attending one of the major teaching hospitals in Dublin. Symptom burden was measured using the Memorial Symptom Assessment Scale (MSAS), and the functional performance was measured using the Functional Performance Inventory-Short Form (FPISF). Findings revealed that participants experienced a median of 13 symptoms. The most burdensome symptoms were shortness of breath, lack of energy, difficulty sleeping, worrying, dry mouth, feeling nervous, feeling irritable, and feeling sad. Participants with very severe COPD had the greatest symptom burden, followed by those with severe COPD, moderate COPD, and mild COPD. Symptom burden was higher for the psychological symptoms compared to the physical symptoms. Participants with mild COPD had the highest functional performance, followed by those with moderate COPD, very severe COPD, and severe COPD. Twenty symptoms were negatively correlated with overall functional performance, indicating that high symptom burden for those symptoms was associated with low overall functional performance. Moderate, negative, statistically significant correlations were found between the total symptom burden and overall functional performance, physical symptom burden and overall functional performance and psychological symptom burden and overall functional performance. A negative linear relationship was found between total symptom burden and overall functional performance among all stages of COPD except the mild group. No relationship was found between total symptom burden and overall functional performance for the moderate group. Healthcare professionals need to broaden the clinical and research assessment of physical and psychological symptoms in COPD; alleviating the burden of these symptoms may promote improved functional performance.

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Ulva rigida (UR) and Palmaria palmata (PP) were included in farmed Atlantic salmon diets at levels of 0-15% for 19 and 16 weeks, respectively. Quality and shelf-life parameters of salmon fillets stored in modified atmosphere packs (MAP) (60% N2 : 40% CO2) at 4ºC were compared to controls fed astaxanthin. Salmon fillets were enhanced with a yellow/orange colour. Proximate composition, pH and lipid oxidation were unaffected by dietary UR and PP. Salmon fed 5% UR and 5-15% PP did not influence sensory descriptors (texture, odour, oxidation flavour and overall acceptability) of cooked salmon fillets. Pig diets were supplemented with commercial wet- and spray-dried macroalgal (Laminaria digitata) polysaccharide extracts containing laminarin (L, 500 mg/kg feed) and fucoidan (F, 420 mg/kg feed) (L/F-WS, L/F-SD) for 3 weeks and quality and shelf-life parameters of fresh pork steaks (longissimus thoracis et lumborum) stored in MAP (80% O2 : 20% CO2) were examined. Level (450 or 900 mg L and F/kg feed) and duration (3 or 6 weeks) of dietary L/F-WS and mechanisms of antioxidant activities in pork were investigated. L/F-WS reduced (p < 0.05) lipid oxidation and lowered levels of saturated fatty acids in fresh pork after 3 weeks feeding. L/F-SD was added directly to mince pork (0.01 - 0.5%) and quality and shelf-life parameters of fresh pork patties stored in MAP (80% O2 : 20% CO2) were assessed. Direct addition of the L/F-SD increased levels of lipid oxidation and decreased surface redness (a* values) of fresh pork patties. Lipid oxidation was reduced in cooked patties due to the formation of Maillard reaction products. Cooked pork patties containing L/F-SD were subjected to an in vitro digestion and a cellular transwell model to confirm bioaccessibility and uptake of antioxidant compounds. In mechanistic studies, fucoidan demonstrated antiand pro-oxidant activities on muscle lipids and oxymyoglobin, respectively.

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Background: Reablement, also known as restorative care, is one possible approach to home-care services for older adults at risk of functional decline. Unlike traditional home-care services, reablement is frequently time-limited (usually six to 12 weeks) and aims to maximise independence by offering an intensive multidisciplinary, person-centred and goal-directed intervention. Objectives: To assess the effects of time-limited home-care reablement services (up to 12 weeks) for maintaining and improving the functional independence of older adults (aged 65 years or more) when compared to usual home-care or wait-list control group. Search methods: We searched the following databases with no language restrictions during April to June 2015: the Cochrane Central Register of Controlled Trials (CENTRAL); MEDLINE (OvidSP); Embase (OvidSP); PsycINFO (OvidSP); ERIC; Sociological Abstracts; ProQuest Dissertations and Theses; CINAHL (EBSCOhost); SIGLE (OpenGrey); AgeLine and Social Care Online. We also searched the reference lists of relevant studies and reviews as well as contacting authors in the field. Selection criteria: We included randomised controlled trials (RCTs), cluster randomised or quasi-randomised trials of time-limited reablement services for older adults (aged 65 years or more) delivered in their home; and incorporated a usual home-care or wait-list control group. Data collection and analysis: Two authors independently assessed studies for inclusion, extracted data, assessed the risk of bias of individual studies and considered quality of the evidence using GRADE. We contacted study authors for additional information where needed. Main results: Two studies, comparing reablement with usual home-care services with 811 participants, met our eligibility criteria for inclusion; we also identified three potentially eligible studies, but findings were not yet available. One included study was conducted in Western Australia with 750 participants (mean age 82.29 years). The second study was conducted in Norway (61 participants; mean age 79 years). We are very uncertain as to the effects of reablement compared with usual care as the evidence was of very low quality for all of the outcomes reported. The main findings were as follows. Functional status: very low quality evidence suggested that reablement may be slightly more effective than usual care in improving function at nine to 12 months (lower scores reflect greater independence; standardised mean difference (SMD) -0.30; 95% confidence interval (CI) -0.53 to -0.06; 2 studies with 249 participants). Adverse events: reablement may make little or no difference to mortality at 12 months' follow-up (RR 0.97; 95% CI 0.74 to 1.29; 2 studies with 811 participants) or rates of unplanned hospital admission at 24 months (RR 0.94; 95% CI 0.85 to 1.03; 1 study with 750 participants). The very low quality evidence also means we are uncertain whether reablement may influence quality of life (SMD -0.23; 95% CI -0.48 to 0.02; 2 trials with 249 participants) or living arrangements (RR 0.92, 95% CI 0.62 to 1.34; 1 study with 750 participants) at time points up to 12 months. People receiving reablement may be slightly less likely to have been approved for a higher level of personal care than people receiving usual care over the 24 months' follow-up (RR 0.87; 95% CI 0.77 to 0.98; 1 trial, 750 participants). Similarly, although there may be a small reduction in total aggregated home and healthcare costs over the 24-month follow-up (reablement: AUD 19,888; usual care: AUD 22,757; 1 trial with 750 participants), we are uncertain about the size and importance of these effects as the results were based on very low quality evidence. Neither study reported user satisfaction with the service. Authors' conclusions: There is considerable uncertainty regarding the effects of reablement as the evidence was of very low quality according to our GRADE ratings. Therefore, the effectiveness of reablement services cannot be supported or refuted until more robust evidence becomes available. There is an urgent need for high quality trials across different health and social care systems due to the increasingly high profile of reablement services in policy and practice in several countries.