Conservación de subproductos de mataderos para la alimentación animal

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Mechanism of effluent attack on Portland cement and alkali activated mortars

The alkali activation of waste products has become a widespread topic of research, mainly due to environmental benefits. Portland cement and alkali-activated mortar samples were prepared to compare their resistance to silage effluent which contains lactic acid. The mechanism of attack on each sample has also been investigated.

Piñatex, the design development of a new sustainable material

This is a research project by practice, which firstly develops a new material invention derived from natural fibres extracted from waste pineapple leaves; secondly it articulates the contemporary designer’s role in facilitating sustainable solutions through: Insights from my own material invention, PiñatexTM, which integrates the materiality of design with the immateriality of concepts and values Developing a visual model of mapping I began with these questions: ‘What are the challenges in seeking to make a new and sustainable material from the waste products of pineapple agriculture in the Philippines?’ and ‘How can a design practice link elements of materiality (artifacts) with immaterial elements (value systems) in order to improve sustainable social and economic development?’ Significant influences have been the work of Papanek1 (2003), Hawken2 (1999) and Abouleish3 (2008) and in particular the ethical business model initiated by McDonough and Braungart in Cradle to Cradle®4 (2002). My own research project is inspired by the Cradle to Cradle® model. It proposes the development of a new material, PiñatexTM which is derived from natural fibres extracted from waste pineapple leaves and could be used in a wide variety of products that are currently fabricated in leather or petroleum-based materials. The methods have comprised: Contextual reviews; case studies (SEKEM, Cradle to Cradle® and Gawad Kalinga); practical experiments in the field of natural fibres, chemistry, product development, manufacturing and prototyping, leading to an invention and a theoretical model of mapping. In addition, collaboration has taken place across scientific, technological, social, ecological, academic and business fields. The outcome is a new material based on the synchronicity between the pineapple fibres, polymers, resins and coatings specially formulated. The invention of the new material that I developed as a central part of this research by practice has a patent in the national phase (PCT/GB 2011/000802) and is in the first stages of manufacturing, commercial testing and further design input (Summer 2014). The contribution to knowledge is firstly the material, PiñatexTM, which exhibits certain key qualities, namely environmentally non-toxic, biodegradable, income-generating potential and marketability. This is alongside its intrinsic qualities as a textile product: aesthetic potential, durability and stability, which will make it suitable for the accessories, interiors and furnishing markets. The theoretical mapping system Upstream and Downstream forms a secondary contribution.

Experimental study on polyester based concretes filled with glass fibre reinforced plastic recyclates – a contribution to composite materials sustainability

The development and applications of thermoset polymeric composites, namely fibre reinforced plastics (FRP), have shifted in the last decades more and more into the mass market [1]. Despite of all advantages associated to FRP based products, the increasing production and consume also lead to an increasing amount of FRP wastes, either end-of-lifecycle products, or scrap and by-products generated by the manufacturing process itself. Whereas thermoplastic FRPs can be easily recycled, by remelting and remoulding, recyclability of thermosetting FRPs constitutes a more difficult task due to cross-linked nature of resin matrix. To date, most of the thermoset based FRP waste is being incinerated or landfilled, leading to negative environmental impacts and supplementary added costs to FRP producers and suppliers. This actual framework is putting increasing pressure on the industry to address the options available for FRP waste management, being an important driver for applied research undertaken cost efficient recycling methods. [1-2]. In spite of this, research on recycling solutions for thermoset composites is still at an elementary stage. Thermal and/or chemical recycling processes, with partial fibre recovering, have been investigated mostly for carbon fibre reinforced plastics (CFRP) due to inherent value of carbon fibre reinforcement; whereas for glass fibre reinforced plastics (GFRP), mechanical recycling, by means of milling and grinding processes, has been considered a more viable recycling method [1-2]. Though, at the moment, few solutions in the reuse of mechanically-recycled GFRP composites into valueadded products are being explored. Aiming filling this gap, in this study, a new waste management solution for thermoset GFRP based products was assessed. The mechanical recycling approach, with reduction of GFRP waste to powdered and fibrous materials was applied, and the potential added value of obtained recyclates was experimentally investigated as raw material for polyester based mortars. The use of a cementless concrete as host material for GFRP recyclates, instead of a conventional Portland cement based concrete, presents an important asset in avoiding the eventual incompatibility problems arisen from alkalis silica reaction between glass fibres and cementious binder matrix. Additionally, due to hermetic nature of resin binder, polymer based concretes present greater ability for incorporating recycled waste products [3]. Under this scope, different GFRP waste admixed polymer mortar (PM) formulations were analyzed varying the size grading and content of GFRP powder and fibre mix waste. Added value of potential recycling solution was assessed by means of flexural and compressive loading capacities of modified mortars with regard to waste-free polymer mortars.

Life without Phd? – Phd Oxygen Sensor Proteins in Hypoxic Carcinoma Cell Survival

The microenvironment within the tumor plays a central role in cellular signaling. Rapidly proliferating cancer cells need building blocks for structures as well as nutrients and oxygen for energy production. In normal tissue, the vasculature effectively transports oxygen, nutrient and waste products, and maintains physiological pH. Within a tumor however, the vasculature is rarely sufficient for the needs of tumor cells. This causes the tumor to suffer from lack of oxygen (hypoxia) and nutrients as well as acidification, as the glycolytic end product lactate is accumulated. Cancer cells harbor mutations enabling survival in the rough microenvironment. One of the best characterized mutations is the inactivation of the von Hippel-Lindau protein (pVHL) in clear cell renal cell carcinoma (ccRCC). Inactivation causes constitutive activation of hypoxia-inducible factor HIF which is an important survival factor regulating glycolysis, neovascularization and apoptosis. HIFs are normally regulated by HIF prolyl hydroxylases (PHDs), which in the presence of oxygen target HIF α-subunit to ubiquitination by pVHL and degradation by proteasomes. In my thesis work, I studied the role of PHDs in the survival of carcinoma cells in hypoxia. My work revealed an essential role of PHD1 and PHD3 in cell cycle regulation through two cyclin-dependent kinase inhibitors (CKIs) p21 and p27. Depletion of PHD1 or PHD3 caused a cell cycle arrest and subjected the carcinoma cells to stress and impaired the survival.

Walker Brothers Quarries Limited fonds, 1975, 1980-1981, 1984, 1987-1989

Serving the Niagara and surrounding areas for over 120 years, Walker Industries has made its impact not only commercially, but also culturally. Beginning in 1875 with the erection of a stone sawing mill on a property John Walker purchased from the Welland Canal Loan Company. One of the first projects Walker cut stone for was the Merritton Town Hall. In 1882 the business expanded to include Walkers children, changing the name to Walker & Sons. Eventually in 1887 the two eldest sons took control of the business operation and their partnership changed the company’s name to Walker Brothers, the same year the company began operating its first quarry. The quarry was conveniently located alongside the 3rd Welland canal, offering easy access to Toronto and Hamilton. It was also close to the railway system which allowed immediate access to Thorold and Niagara Falls and later access to parts of Ontario and Quebec. The quarry supplied stone to build numerous halls and armouries across Ontario. A use was also found for the ‘waste products’ of cutting the limestone. Leftover stone chips were sent to paper mills, where stone was needed as part of the sulphite pulp process for making paper. Beginning to supply the Ontario Paper Company with stone in 1913, meant not only long, hard, work, but also more profit for the company. Before mechanization, most of the loading and unloading of the stone was done by hand, taking 19 man-hours to load an 18 yard railway car. Mechanization followed in 1947 when the plant became fully mechanized making the work easier and increasing production rates. In 1957 the company moved from its original location and opened the St. Catharines Crushed Stone Plant.

Anàlisi de la situació dels residus d’aparells elèctrics i electrònics (RAEE) al Gironès

Estudi de la situació dels residus d’aparells elèctrics i electrònics al Gironès reformulant la seva gestió actual, valorant si caldria fer una nova planta, així com una campanya de sensibilització social i construcció d’una possible planta intermediària de triatge de RAEE per a la comarca del Gironès

Diagnóstico Ambiental de la FAREM-Estelí y Propuestas de Gestión

Como estudiantes de Ciencias Ambientales se nos dio la posibilidad de realizar un estudio en una universidad de Estelí (Nicaragua), concretamente en la Facultad Regional Multidisciplinaria de Estelí (FAREM-Estelí). Durante nuestra estancia en Nicaragua realizamos un estudio de la situación actual de los residuos sólidos, el agua y la energía en la FAREM. También diseñamos un conjunto de propuestas de mejora en la gestión ambiental para solucionar el problema de los residuos sólidos y conseguir una reducción en el consumo de agua y energía en el centro. Los objetivos generales de este proyecto han sido: realizar un diagnóstico ambiental de la Facultad Regional Multidisciplinaria-Estelí y elaborar propuestas de mejora en la gestión ambiental

Revaloració de la fracció cel·lular de la sang de porc procedent d'escorxadors industrials

La sang de porc és un subproducte comestible que es genera als escorxadors industrials durant el procés d'obtenció de la canal. Aquest subproducte es caracteritza per presentar una elevada càrrega contaminant i, degut a l'elevat volum que es genera, és necessari trobar estratègies que permetin la seva revaloració i aprofitament, a la vegada que disminuïm la contaminació ambiental i les despeses que es deriven del seu processament abans de l'abocament. La fracció cel·lular (FC) constitueix el 40 % de la sang de porc i conté principalment l'hemoglobina (Hb), que representa al voltant del 90 % del contingut en proteïna d'aquesta fracció (un 35 % aproximadament). L'elevat percentatge en proteïna i en ferro, i les seves bones propietats funcionals fan que l'aprofitament d'aquest subproducte com a primera matèria o ingredient de la indústria alimentària sigui una alternativa molt útil a l'hora de reduir les despeses de la indústria càrnia, sempre que es resolguin els problemes de l'enfosquiment i dels sabors estranys que pot conferir la FC quan s'addiciona a productes alimentaris. Una altra possible utilització de la FC és aprofitar les propietats colorants de l'Hb o del grup hemo, com a colorant d'origen natural en diversos productes alimentaris. Els objectius del present treball eren, en primer lloc, determinar les millors condicions d'aplicació del procés de conservació de la FC mitjançant la deshidratació per atomització i caracteritzar físico-químicament i microbiològica el concentrat d'Hb en pols. En segon lloc, avaluar l'eficàcia de diferents additius antioxidants i/o segrestants del ferro per prevenir l'enfosquiment que pateix la FC durant la deshidratació. En tercer lloc, aplicar tractaments d'altes pressions hidrostàtiques com a procés d'higienització i avaluar els efectes d'aquest tractament sobre la microbiota contaminant, el color i les propietats funcionals de la FC. Finalment, desenvolupar un procés d'obtenció d'hidrolitzats proteics descolorats a partir de l'Hb amb la finalitat d'utilitzar-los com a ingredients nutricionals i/o funcionals. La millor temperatura de deshidratació per atomització de la FC hemolitzada era 140ºC. La FC en pols presentava un contingut en humitat del 5,3 % i un percentatge de solubilitat proteica del 96 %. La deshidratació per atomització induïa canvis en l'estructura nativa de l'Hb i, per tant, un cert grau de desnaturalització que pot conduir a una disminució de les seves propietats funcionals. L'extracte sec de la FC en pols estava composat per un 94,6 % de proteïna, un 3 % de sals minerals i un 0,7 % de greix. Els valors CIE L*a*b* del color de la FC en pols eren força constants i reflectien el color vermell marró fosc d'aquesta, a causa de l'oxidació del ferro hèmic que es produeix durant la deshidratació. La càrrega contaminant de la FC fresca de la sang de porc era força elevada i el tractament d'hemòlisi amb ultrasons i la centrifugació posterior no produïen una reducció significativa de la microbiota contaminant, obtenint un producte amb uns recomptes microbiològics de l'ordre de 106 ufc·mL-1. La deshidratació per atomització produïa una disminució d'una unitat logarítmica dels recomptes totals de la FC hemolitzada. Tanmateix, el producte en pols encara reflectia l'elevada contaminació de la primera matèria, fet que condiciona negativament la seva utilització com a ingredient alimentari, a no ser que es millorin les condicions de recollida de la sang a l'escorxador o que aquesta o la FC es sotmeti a algun tractament d'higienització prèviament a la deshidratació. Les isotermes de sorció a 20ºC de la FC en pols tenien forma sigmoïdal i una histèresi estreta i llarga. L'equació GAB és un bon model matemàtic per ajustar les dades de sorció obtingudes experimentalment i determinar la isoterma d'adsorció de la FC deshidratada per atomització. El percentatge d'humitat de la FC deshidratada a 140ºC es corresponia a un valor d'aw a 20 ºC d'aproximadament el 0,16. Tenint en compte que estava per sota dels valors d'aw corresponents a la capa monomolecular, es pot garantir la conservació a temperatura ambient del producte, sempre que s'envasi en recipients tancats que no permetin l'entrada d'humitat de l'exterior. De l'estudi de la possible estabilització del color de la FC deshidratada per atomització mitjançant l'addició d'antioxidants i/o segrestants de ferro, es va observar que només l'àcid ascòrbic, la glucosa, l'àcid nicotínic i la nicotinamida, tenien efectes positius sobre el color del producte en pols. L'ascòrbic i la glucosa no milloraven la conservació del color de l'Hb però disminuïen l'enfosquiment que es produeix durant la deshidratació, amb la qual cosa es pot obtenir un producte en pols de color marró més clar. L'addició de dextrina o L-cisteïna no disminuïa l'enfosquiment ni evitava el canvi de color de l'Hb. L'àcid nicotínic i la nicotinamida protegien el color de l'Hb durant el procés de deshidratació i l'emmagatzematge de la FC en pols. Les millors condicions d'aplicació del tractament amb altes pressions hidrostàtiques (HHP) sobre la FC eren 400 MPa, a 20ºC, durant 15 minuts, perquè produïen una millora significativa de la qualitat microbiològica, no afectaven negativament al color, no comprometien gaire la solubilitat proteica l'Hb i, malgrat que produïen un augment de la viscositat, la FC romania fluida després del tractament. Aquest tractament permetia una reducció de la microbiota contaminant de la FC d'entre 2 i 3 unitats logarítmiques. L'aplicació de l'alta pressió i la posterior deshidratació per atomització permetien obtenir un producte en pols amb recomptes totals de l'ordre de 2,8 unitats logarítmiques. El color de la FC pressuritzada en pols era igual que el de la FC control deshidratada, perquè ambdues mostres presentaven la mateixa susceptibilitat a l'oxidació del grup hemo produïda per la deshidratació. L'alta pressió incrementava la susceptibilitat de l'Hb als efectes desnaturalitzants de la deshidratació, fonamentalment a pH 7 (PIE), ja que es va observar una disminució de la solubilitat proteica a pH neutre després dels 2 processos tecnològics. La FC en pols presentava una màxima capacitat escumant al PIE de l'Hb. L'aplicació del tractament HHP produïa una disminució de la capacitat escumant de la FC en pols, però no tenia efectes negatius sobre l'estabilitat de l'escuma formada. Tampoc es van observar efectes negatius del tractament HHP sobre l'activitat emulsionant de l'Hb. La màxima activitat emulsionant de l'Hb s'aconseguia amb una concentració de FC en pols de l'1,5 % a pH 7 i de l'1 % a pH 4,5. Les pastes obtingudes per escalfament de la FC presentaven característiques molt diferenciades depenent del pH. A pH neutre es formaven unes pastes dures i consistents, mentre que a pH àcid les pastes eren poc consistents, molt adhesives i més elàstiques que les anteriors. Aquestes tenien una capacitat de retenció d'aigua molt superior que les de pH 7, en les quals l'aigua quedava retinguda per capil·laritat. La textura i capacitat de retenció d'aigua de les pastes tampoc eren afectades pel tractament HHP. El tractament HHP incrementava l'activitat de la Tripsina sobre l'Hb quan el substrat i l'enzim es tractaven conjuntament i afavoria el procés d'obtenció d'hidrolitzats descolorats a partir de la FC, la qual cosa permetia assolir el mateix grau de descoloració amb una dosi d'enzim inferior. El tractament d'hidròlisi de la FC amb la utilització combinada de Tripsina seguida d'un tractament amb Pepsina permetia l'obtenció d'un hidrolitzat proteic d'Hb descolorat i hidrolitzava completament la globina, donant lloc a 2 pèptids de 10,8 i 7,4 KDa. Val a dir que també produïa un 60 80 % de nitrogen soluble en TCA, constituït fonamentalment per pèptids petits i aminoàcids lliures. Els hidrolitzats trípsics i pèpsics d'Hb, obtinguts a partir de FC no pressuritzada i deshidratats per atomització a 180ºC, eren de color blanc i tenien un contingut en humitat del 4,7 %, un 84,2 % de proteïna i 9,7 % de sals minerals. El procés d'hidròlisi permetia una reducció considerable de la contaminació de la FC, obtenint un producte en pols amb uns recomptes totals de l'ordre de 102-103 ufc·g-1. Pel que fa a la funcionalitat dels hidrolitzats d'Hb deshidratats per atomització, aquests presentaven una elevada solubilitat proteica a pH 5 i 7 i romanien solubles després d'un escalfament a 80ºC durant 30 min. Tanmateix, aquesta hidròlisi afectava molt negativament la capacitat de mantenir escumes estables i l'activitat emulsionant.

Cropping systems, carbon sequestration and erosion in Brazil, a review

Soils represent a large carbon pool, approximately 1500 Gt, which is equivalent to almost three times the quantity stored in terrestrial biomass and twice the amount stored in the atmosphere. Any modification of land use or land management can induce variations in soil carbon stocks, even in agricultural systems that are perceived to be in a steady state. Tillage practices often induce soil aerobic conditions that are favourable to microbial activity and may lead to a degradation of soil structure. As a result, mineralisation of soil organic matter increases in the long term. The adoption of no-tillage systems and the maintenance of a permanent vegetation cover using Direct seeding Mulch-based Cropping system or DMC, may increase carbon levels in the topsoil. In Brazil, no-tillage practices (mainly DMC), were introduced approximately 30 years ago in the south in the Parana state, primarily as a means of reducing erosion. Subsequently, research has begun to study the management of the crop waste products and their effects on soil fertility, either in terms of phosphorus management, as a means of controlling soil acidity, or determining how manures can be applied in a more localised manner. The spread of no-till in Brazil has involved a large amount of extension work. The area under no-tillage is still increasing in the centre and north of the country and currently occupies ca. 20 million hectares, covering a diversity of environmental conditions, cropping systems and management practices. Most studies of Brazilian soils give rates of carbon storage in the top 40 cm of the soil of 0.4 to 1.7 t C ha(-1) per year, with the highest rates in the Cerrado region. However, caution must be taken when analysing DMC systems in terms of carbon sequestration. Comparisons should include changes in trace gas fluxes and should not be limited to a consideration of carbon storage in the soil alone if the full implications for global warming are to be assessed.

'Green' treatment of acid mine drainage - a step towards sustainability

Sustainability is becoming increasingly important in the mining and mineral processing industries and must incorporate the associated waste products. Acid mine drainage (AMD) is one such by-product and is one of the most serious environmental problems facing the minerals industry today. The oxidation of sulphidic mine wastes often continues for a substantial period of time after mine closure, resulting in difficult and costly remediation and rehabilitation works. Mining companies are often reluctant to spend increasing amounts of money on waste treatment when the mine life is limited or even finished. Hence a simple, low maintenance and low-cost method of treating AMD is required. Whilst this paper does not address the issue of AMD, it does propose methods for removal of individual species from AMD with potential benefits, including raising AMD pH.

A novel concept of using biosolids as a biological adsorbent, or ‘biosorbent’, of metals from AMD is being investigated at a laboratory/pilot scale level. Biosolids are a by-product resulting from the biological treatment of wastewater, and have been previously shown to adsorb metals from aqueous solutions. This could lead to an environmentally sustainable or ‘green’ method for treating both AMD discharges and disposing/reusing the biosolids.

The result of a laboratory-scale study of the biosorption of Zn(II) is presented in this paper. Physical parameters including reaction kinetics, mixing speed and solution pH were investigated. Solution pH also rose an average of 2 pH units over the 24 hour equilibrium time – a valuable side effect when treating acid mine drainage. The outcome of the study highlights the usefulness of biosolids as a biosorbent for the removal/recovery of metal ions from acid mine drainage. A simple, low-cost treatment technology requiring low maintenance would be beneficial to the mining industry to address some issues relating to AMD and would help integrate environmental and economic considerations into sustainable environmental management.

In situ stabilisation of pavements using cementitious binders

An extensive study was made of the physical properties of a range of cementitiously stabilised materials to determine their suitability for use in in situ pavement construction. This process for recycling existing pavements has considerable environmental and cost benefits. Pavement models incorporating these materials were analysed to determine their structural behaviour.

Mothering siblings: Diaspora, desire and identity in American born confused Desi

In this essay we consider the construction of cultural identity, motherhood and the family in ABCD, a film of the Indian diaspora that had its world premiere at the 2001 London Film Festival. This film reads family, apparently within familiar narrative structures such as the U.S.-immigrant story, as portrayed in films like Goodbye, Columbus and My Big Fat Greek Wedding, and the "leaving home" story, as classically portrayed in Pride and Prejudice, where a young person needs to escape from her clueless family. The irritating presence of the mother in the film, and the quickness with which her two children appear to make life-determining decisions following her death, seem to invite discussions of plot and character organized around ideas of individual development, self-improvement and understanding. This is the territory of the desire plot, an account of family history captured for the twentieth century by Freudian-Lacanian readings which position sexual desire within the unconscious history of familial fantasies, understood as vertical and Oedipal. In this territory, mothers and old ladies become, as Mary Jacobus memorably phrased it, little more than "the waste products" of a system in which marriageable women are objects of exchange between men (142) and a mother's death would be expected to grease the wheels of narrative. Identity and narrative are inextricably linked here: a certain understanding of narrative as developmental and teleological paves the way for an understanding of identity as either/or. There are problems, however, in trying to read ABCD as a bildüngsroman structured by what Susan Freidman calls "the temporal plots of the family romance, its repetitions and discontents" (137), rendering the "Indian" characteristics of the plot unreadable, and the apparently self-defeating nature of the characters' choices and behavior, rather pointless. A central [End Page 16] difficulty is that the film both responds to and resists readings based on the Oedipal model of the bildüngsroman with its focus on linear development through time.

What happens during natural protein fibre dissolution in ionic liquids

Here, we monitor the dissolution of several natural protein fibres such as wool, human hair and silk, in various ionic liquids (ILs). The dissolution of protein-based materials using ILs is an emerging area exploring the production of new materials from waste products. Wool is a keratin fibre, which is extensively used in the textiles industry and as a result has considerable amounts of waste produced each year. Wool, along with human hair, has a unique morphology whereby the outer layer, the cuticle, is heavily cross linked with disulphide bonds, whereas silk does not have this outer layer. Here we show how ILs dissolve natural protein fibres and how the mechanism of dissolution is directly related to the structure and morphology of the wool fibre. © 2014 by the authors; licensee MDPI, Basel, Switzerland.