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11.
The Biofuels Directive proposes 5.75% of transport fuel (by energy) to be replaced by biofuel in the year 2010. This equates to 11.3 PJ in Ireland, which equates to 538 million litres of ethanol or 323 million litres of biodiesel. However, if using biodiesel produced through bioesterification of rapeseed oil, then 6.3% of Irish agricultural land is required to produce 5.75% of transport fuel. Furthermore this equates to 70% of arable land.Using ethanol produced from wheat, 3.9% of Irish agricultural land is required to produce 5.75% of transport fuel. Ethanol produces less energy from a crop, than the energy in the biogas generated when the crop is digested. The ethanol production process uses up to 60% of the produced energy in the final ethanol product. It is shown for compressed biomethane generated from silage that the total parasitic demand of the process is of the order of 25%.Grass/silage is a crop that Irish farmers are familiar with, over 90% of Irish agricultural land is under grass. Grass does not require rotation, it does not require annual ploughing (releasing NOx), and it sequesters carbon into the soil. Digesting silage, scrubbing the biogas to biomethane, and compressing and utilizing it as a transport fuel, is suggested to be the optimum biofuel for Ireland. The 2010 biofuels target can be met with 1.6% of agricultural land; this is four times less land than required using rapeseed. A conservative economic analysis would suggest a lower cost than ethanol produced from wheat. 相似文献
12.
Sonia Partap Niamh A. Plunkett Daniel J. Kelly Fergal J. O’Brien 《Journal of materials science. Materials in medicine》2010,21(8):2325-2330
Osteoblasts respond to mechanical signals which play a key role in the formation of bone however, after extended periods of
stimulation they become desensitised. Mechanosensitivity has been shown to be restored by the introduction of resting periods
between loadings. The aim of this study was to analyse the effect of rest periods on the response of osteoblast-like cells
seeded on collagen-glycosaminoglycan (CG) scaffolds in a flow perfusion bioreactor up to 14 days. Short (10 s) and long (7 h)
term rests were incorporated into stimulation patterns. Constructs cultured in the bioreactor had a more homogenous cell distribution
albeit with lower cell numbers than the static group. Osteopontin expression was significantly higher on the rest-inserted
group than on the steady flow and static control. These results indicate that the insertion of short term rests during flow
improves cellular distribution and osteogenic responses on CG constructs cultured in a flow perfusion bioreactor. 相似文献
13.
Geert Hellings Andriy HikavyyJerome Mitard Liesbeth WittersBrahim Benbakhti AliReza Alian Niamh WaldronHugo Bender Geert Eneman Raymond Krom Andreas Schulze Wilfried Vandervorst Roger LooMarc Heyns Marc MeurisThomas Hoffmann Kristin De Meyer 《Thin solid films》2012,520(8):3326-3331
The Implant-Free Quantum Well Field-Effect Transistor (FET) offers enhanced scalability in a planar architecture through the integration of heterostructures. The Implant-Free architecture fully utilizes the band offsets between different materials, whereby charge carriers are effectively confined to a thin channel layer. This prevents sub-surface source/drain leakage observed in classical bulk Metal-Oxide-Semiconductor FETs at small gate lengths. An investigation of the VT-tuning capabilities of this technology reveals sensitivity to both well doping and bulk voltage. 相似文献
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15.
Taking a socio-ecological perspective the World Health Organisation recognizes that housing comprises four interrelated dimensions—the physical structure of the house, the home, the neighbourhood infrastructure and the community. Housing related health vulnerability arises when residents are exposed to poor conditions in any one of these dimensions and augmented when two or more co-exists. Regardless the relationship between housing and health in the global south remains largely under explored; in particular there has been little focus on health outcomes resulting from upgrading of informal settlements. Applying this framework we report from an in situ upgrading of the informal settlement of Imizamo Yethu in Cape Town, South Africa. Data gathered from surveys are used to determine whether differences in each of these dimensions exist between housing type; both formal upgrades and shacks. Results show that whilst no significant differences exist in self-reported physical health, residents of formal housing are less likely to report mental health issues, have a stronger sense of belonging and report greater satisfaction with both neighbourhood and home than shack residents. However, these contested spaces are not easily interpreted and community tension, exclusion and disadvantage highlight the complex interactions between each of the interrelated dimensions and policies regarding housing intervention. The paper highlights the complex relationship between housing and health that is often lost in simplistic measures of housing when outcomes related to the indoor environment alone are considered. 相似文献
16.
Timothy P Guinee Claire B Gorry Donal J O'Callaghan Brendan T O'Kennedy Niamh O'Brie Mark A Fenelon 《International Journal of Dairy Technology》1997,50(3):99-106
The effects of various processing parameters on the rennet coagulation properties of milk were assessed. Using low amplitude oscillation rheometry, the coagulation properties were monitored by measurement of the elastic shear modulus, G', as a function of time, t, from rennet addition; Gapos; was taken as a measure of curd firmness. The Scott-Blair time dependency model was fitted to the experimental G' It curves for the determination of the following coagulation parameters: gel time, maximum curd firming rate, the set-to-cut time at 20 Pa (ie, time to reach 20 Pa) and the curd firmness after a renneting time of 2400 s. The renneting properties were enhanced by increasing the levels of milk protein and fat in the ranges 0.3–7.0% (w/w) and 0.1–10% (w/w) respectively and by two stage homogenization pressure where the first stage pressure, P1 , was varied from 0 to 25 MPa and the second stage pressure, P2 , was held constant at 5 MP a. The influence of these parameters, within the range investigated, in complementing the gel forming properties decreased in the following order: protein > fat > homogenization pressure. In contrast, the coagulation properties of milk were impaired by high heat treatment, the addition of a commercial microparticulated whey protein based fat substitute and by partial replacement of protein with fat. 相似文献
17.
Plasma fatty acid patterns reflect dietary habits and metabolic health: A cross‐sectional study
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18.
The effect of temperature on the degradation of blackcurrant anthocyanins in a model juice system was determined over a temperature range of 4–140 °C. The thermal degradation of anthocyanins followed pseudo first-order kinetics. From 4–100 °C an isothermal method was used to determine the kinetic parameters. In order to mimic the temperature profile in retort systems, a non-isothermal method was applied to determine the kinetic parameters in the model juice over the temperature range 110–140 °C. The results from both isothermal and non-isothermal methods fit well together, indicating that the non-isothermal procedure is a reliable mathematical method to determine the kinetics of anthocyanin degradation. The reaction rate constant (k) increased from 0.16 (±0.01) × 10−3 to 9.954 (±0.004) h−1 at 4 and 140 °C, respectively. The temperature dependence of the rate of anthocyanin degradation was modelled by an extension of the Arrhenius equation, which showed a linear increase in the activation energy with temperature. 相似文献
19.
Vanessa Penna Niamh Moriarty Yi Wang Kevin C. L. Law Carlos W. Gantner Richard J. Williams David R. Nisbet Clare L. Parish 《International journal of molecular sciences》2022,23(9)
Clinical studies have provided evidence for dopamine (DA) cell replacement therapy in Parkinson’s Disease. However, grafts derived from foetal tissue or pluripotent stem cells (PSCs) remain heterogeneous, with a high proportion of non-dopaminergic cells, and display subthreshold reinnervation of target tissues, thereby highlighting the need to identify new strategies to improve graft outcomes. In recent work, Stromal Cell-Derived Factor-1 (SDF1), secreted from meninges, has been shown to exert many roles during ventral midbrain DA development and DA-directed differentiation of PSCs. Related, co-implantation of meningeal cells has been shown to improve neural graft outcomes, however, no direct evidence for the role of SDF1 in neural grafting has been shown. Due to the rapid degradation of SDF1 protein, here, we utilised a hydrogel to entrap the protein and sustain its delivery at the transplant site to assess the impact on DA progenitor differentiation, survival and plasticity. Hydrogels were fabricated from self-assembling peptides (SAP), presenting an epitope for laminin, the brain’s main extracellular matrix protein, thereby providing cell adhesive support for the grafts and additional laminin–integrin signalling to influence cell fate. We show that SDF1 functionalised SAP hydrogels resulted in larger grafts, containing more DA neurons, increased A9 DA specification (the subpopulation of DA neurons responsible for motor function) and enhanced innervation. These findings demonstrate the capacity for functionalised, tissue-specific hydrogels to improve the composition of grafts targeted for neural repair. 相似文献