Cellulose Acetate Microbeads for Controlled Delivery of Essential Micronutrients

The controlled delivery of micronutrients to soil and plants is essential to increase agricultural yields. However, this is today achieved using fossil fuel-derived plastic carriers, posing environmental risks and contributing to global carbon emissions. In this work, a novel and efficient way to prepare biodegradable zinc-impregnated cellulose acetate beads for use as controlled release fertilizers is presented. Cellulose acetate solutions in DMSO were dropped into aqueous antisolvent solutions of different zinc salts. The droplets underwent phase inversion, forming solid cellulose acetate beads containing zinc, as a function of zinc salt type and concentration. Even higher values of zinc uptake (up to 15.5%) were obtained when zinc acetate was added to the cellulose acetate–DMSO solution, prior to dropping in aqueous zinc salt antisolvent solutions. The release profile in water of the beads prepared using the different solvents was linked to the properties of the counter-ions via the Hofmeister series. Studies in soil showed the potential for longer release times, up to 130 days for zinc sulfate beads. These results, together with the efficient bead production method, demonstrate the potential of zinc-impregnated cellulose acetate beads to replace the plastic-based controlled delivery products used today, contributing to the reduction of carbon emissions and potential environmental impacts due to the uptake of plastic in plants and animals

Cellulose Acetate Microbeads for Controlled Delivery of Essential Micronutrients

The controlled delivery of micronutrients to soil and plants is essential to increase agricultural yields. However, this is today achieved using fossil fuel-derived plastic carriers, posing environmental risks and contributing to global carbon emissions. In this work, a novel and efficient way to prepare biodegradable zinc-impregnated cellulose acetate beads for use as controlled release fertilizers is presented. Cellulose acetate solutions in DMSO were dropped into aqueous antisolvent solutions of different zinc salts. The droplets underwent phase inversion, forming solid cellulose acetate beads containing zinc, as a function of zinc salt type and concentration. Even higher values of zinc uptake (up to 15.5%) were obtained when zinc acetate was added to the cellulose acetate-DMSO solution, prior to dropping in aqueous zinc salt antisolvent solutions. The release profile in water of the beads prepared using the different solvents was linked to the properties of the counter-ions via the Hofmeister series. Studies in soil showed the potential for longer release times, up to 130 days for zinc sulfate beads. These results, together with the efficient bead production method, demonstrate the potential of zinc-impregnated cellulose acetate beads to replace the plastic-based controlled delivery products used today, contributing to the reduction of carbon emissions and potential environmental impacts due to the uptake of plastic in plants and animals.</p

WANDA: A Radically New Approach for Low-Cost Environmental Monitoring

The cost of monitoring pollutants within natural waters is of major concern. Existing and forthcoming bodies of legislation continually drive the demand for spatial and selective monitoring of key pollutants within our environment. Although research and commercial entities continue to drive down the cost of the infrastructure involved in environmental sensing systems (with an aim to increase scalability), the realisation of deploying a number of such systems even now remains out of reach. High cost and maintenance continue to persist as the major limiting factors. The aim of this work is to combine recent advances in robotics with chemical sensing techniques to remove all but the chemo-responsive material from each sensing node, and package the sensing element within a low cost, mobile, biomimetic robotic fish for effective water quality monitoring. Consequently, this approach is believed to radically reduce the systemic cost and maintenance per node and in doing so it will increase the scalability for spatial and selective monitoring of key pollutants within our environment

Wireless aquatic navigator for detection and analysis (WANDA)

The cost of monitoring and detecting pollutants in natural waters is of major concern. Current and forthcoming bodies of legislation will continue to drive demand for spatial and selective monitoring of our environment, as the focus increasingly moves towards effective enforcement of legislation through detection of events, and unambiguous identification of perpetrators. However, these monitoring demands are not being met due to the infrastructure and maintenance costs of conventional sensing models. Advanced autonomous platforms capable of performing complex analytical measurements at remote locations still require individual power, wireless communication, processor and electronic transducer units, along with regular maintenance visits. Hence the cost base for these systems is prohibitively high, and the spatial density and frequency of measurements are insufficient to meet requirements. In this paper we present a more cost effective approach for water quality monitoring using a low cost mobile sensing/communications platform together with very low cost stand-alone ‘satellite’ indicator stations that have an integrated colorimetric sensing material. The mobile platform is equipped with a wireless video camera that is used to interrogate each station to harvest information about the water quality. In simulation experiments, the first cycle of measurements is carried out to identify a ‘normal’ condition followed by a second cycle during which the platform successfully detected and communicated the presence of a chemical contaminant that had been localised at one of the satellite stations

Lest we remember? Recollection of the Boer War and Great War in Ireland

Recalled memories are recalled from somewhere, and usually for some specific reason. After a generation of forgetting, Irish history has recalled the First World War and the participation of thousands of Irishmen in the service of the British Army. This recent burst of recollection has played a major role in the choreography of the peace process in Northern Ireland. Newly resurrected memory allows southern nationalists to join with northern unionists in commemorating an all-Ireland sacrifice. Nationalists can broaden their sense of nationhood to include those who fought in the ‘wrong’ war, and unionists can identify common values in their neighbours across the border. Historians, both professional and amateur, recovered this uncomfortable memory from beneath the foundation myth of the southern Irish state. From 1922 to the 1980s, official Irish history had prioritised the quasi-religious sacrifice of the Easter Rising in 1916 and the War of Independence which led to the foundation of the Irish Free State in 1922. The awkward fact that tens of thousands of Irishmen wore British uniforms in Europe, while hundreds of their countrymen fought against that same uniform in Dublin, received little coverage in school history texts. Even less space was given to the bitter Civil War which followed independence, as memories were allowed to cool and hopefully decay. This is not a straightforward account of forgetting and remembering, however, as an earlier conflict involving thousands of Dubliners has almost completely disappeared from popular Irish memory. Despite the existence of major monuments in the centre of Dublin, the memory of the South African or Boer War (1899-1902) has not attracted the same celebrity as the First World War. In relatively recent history, Irish troops in British uniform fought and died on a distant African battlefield. Intense coverage in the contemporary press, widespread public interest and profound grief (especially in Dublin city) marked the conflict out as a significant event, yet today it is forgotten. This article examines the very different forgetting and remembering applied to the South African and First World Wars. It addresses the political and social motivations for remembering. Using submerged memories in the built environment the article reflects on the space between remembering and forgetting; that national attic where histories are stored – just in case they are ever needed.Les souvenirs rappelés viennent de quelque part, et généralement pour une raison spécifique. Après une génération d’oubli, la Première Guerre mondiale et la participation de milliers d’Irlandais au service de l’armée britannique viennent d’être rappelées dans l’histoire irlandaise. La chorégraphie du processus de paix en Irlande du Nord s’est bâtie en grande partie grâce cette irruption récente des souvenirs. Ces souvenirs si récemment renouvelés permettent aux nationalistes du Sud de commérorer, avec les unionistes de Nord, le sacrifice de l’île dans son ensemble. Le sentiment de nation des nationalistes s’elargit pour accueillir ceux qui ont combattu dans la “fausse” guerre, tandis que la possibilité d’identifier des valeurs communes avec leurs voisins de l’autre coté de la frontière se présente aux unionistes. Des historiens, amateurs et professionels, ont récupéré cette mémoire gênante par dessous le mythe de la fondation de l‘Etat du sud de l’Irlande. De 1922 à 1980, l’histoire officielle irlandaise avait donné priorité au sacrifice quasi-religieux de l’insurrection de Pâques en 1916, et la Guerre d’Indépendance sur laquelle la fondation de l’Etat libre s’est construite. Le fait gênant que des dizaines de milliers d'Irlandais portaient des uniformes britanniques en Europe, tandis que des centaines de leurs compatriotes se battaient contre ce même uniforme à Dublin, a été rarement cité dans les textes scolaires d'histoire. Encore moins de place a été consacrée à la violente Guerre civile qui a suivi l'indépendance. Cependant, ceci n'est pas simplement une question d'oubli et de souvenance, car un conflit prédédent impliquant des milliers de Dublinois a presque complètement disparu de la mémoire irlandaise populaire. Malgré l'existence de grands monuments aux morts dans le centre de Dublin, la mémoire de la Guerre de l’Afrique du Sud — la Guerre des Boers (1899-1902) — où des troupes irlandaises portant l’uniforme britannique sont mortes sur un champ de bataille en Afrique, n'a pas connu la même renommée que la Première Guerre mondiale. Bien que la couverture dans la presse contemporaine fût active, une couverture soulignée par l'intérêt du public et leur douleur profonde (en particulier dans la ville de Dublin), ce conflit important est aujourd’hui oublié.Grâce à la lentille de la Guerre des Boers, cet article s’interroge sur la différence entre les oublis  et  les souvenirs de la Guerre de l’Afrique du Sud et de la Première Guerre Mondiale. Il aborde les motivations politiques et sociales du souvenir. En se servant des mémoires submergées dans l’architecture urbaine, cette étude cherche à éclairer l’espace entre souvenir et oubli : ce grenier où les histoires nationales sont stockées, au cas où on en aurait besoin

Combined effect of eating speed instructions and food texture modification on eating rate, appetite and later food intake

Modifying food texture and eating slowly each reduce appetite and energy intake. No study has evaluated the effect of combining these measures to slow eating speed and determine the effect on appetite. The aim of this study was to investigate whether there is a combined effect of manipulating oral processing behaviours (OPBs) in this manner on self-reported satiety and subsequent food intake. A 2 × 2 design was used with four breakfast conditions in total. Twenty-four participants attended four study visits where they were asked to consume one of two isocaloric fixed-portion breakfasts differing in texture: 1) granola with milk and 2) yogurt with muesli and conserve. Participants consumed each breakfast twice, with verbal instructions to chew slowly at one visit and at a normal rate at another. Consumption was video-recorded to behaviourally code OPBs. Participants completed visual analogue scales of self-reported appetite measures at the beginning of the test session, immediately prior to and immediately after breakfast consumption. They also completed a food diary documenting food intake for the remainder of the day. The breakfast designed to be eaten slowest (the harder-textured meal with instructions to eat slowly) was eaten at a slower rate, with a greater number of chews per bite and a slower bite rate (p < 0.001) compared to the other meals. No differences were observed between the breakfast conditions on subjective measures of post-prandial satiety, or subsequent energy or macronutrient consumption. Results of this study highlight that combined effects of texture and instructions are most effective at reducing eating rate, though eating slower was not shown to enhance post-meal satiety. Reduced eating speed has previously been shown to reduce ad-libitum energy intake. Future research should consider combined approaches to reduce eating speed, to mitigate the risk of overconsumption within meals