Estudo da produção e aplicação de cola animal

Com as crescentes exigências do mercado e fortes restrições a nível ambiental, as indústrias modernas tendem a progredir no sentido da eficiência, sustentabilidade e rentabilidade dos seus processos produtivos. Sendo a indústria dos curtumes uma forte geradora de resíduos sólidos, é indispensável criar alternativas à valorização desses mesmos resíduos de forma a cumprir todos os requisitos ambientais. Este trabalho remete à reutilização dos resíduos, provenientes da divisão da pele em tripa após operação de descarna, com o intuito de se desenvolver um novo bio-produto apto para ser utilizado noutros sectores industriais. Os resíduos em causa consistem maioritariamente em colagéneo, que apresenta um enorme potencial para se produzir cola animal. Desta forma, este trabalho tem como objectivo principal avaliar a utilização deste tipo de resíduo na produção de um novo bio-produto, cola animal, e testar a sua aplicabilidade técnica e funcional. Com a realização deste trabalho, mostrou-se ser possível produzir um produto, a partir de retalhos da indústria de curtumes, com um perfil de carácter positivo no que diz respeito à viabilidade técnica e funcional da utilização da cola animal como eventual alternativa a um ligante, para formulações de colas de base aquosa para a indústria gráfica e do papel.

Feasibility of creosote treatment for glued-laminated pine-timber railway sleepers

This article studies the possibility of using market available glued-laminated timber (GLT) based on melamine-urea-formaldehyde (MUF) adhesives as an alternative to traditional solid timber sleepers. The study comprised an examination of the effect of creosote treatment on the short-term and durability after accelerated aging of the glue lines (delamination and shear strength) and the potential for full sapwood penetration by the creosote. Creosote treatment showed a negative effect on shear strength and delamination, more severe in the nonstructural than the structural GLT specimens tested. Full penetration of creosote into the sapwood was not achieved. GLT elements based on MUF adhesives can be considered an alternative to solid wood sleepers if specific grading of lamellas, proper treatment schedule, and highly controlled factory production are implemented.

A single method to stain Malassezia furfur and Corynebacterium minutissimum in scales

A single and practical method to slain Malassezia furfur and Corynebacterium minutissimum in lesions' scales is described. The scales are collected by pressing small pieces of scotch tape (about 4 cm lenght and 2 cm width) onto the lesions and following withdrawl the furfuraceous scales will remain on the glue side. These pieces are then immersed for some minutes in lactophenol-cotton blue stain. Following absorption of the stain the scales are washed in current water to remove the excess of blue stain, dried with filter paper, dehydrated via passage in two bottles containing absolute alcohol and then placed in xylene in a centrifugation tube. The xylene dissolves the scotch tape glue and the scales fall free in the tube. After centrifugation and decantation the scales concentrated on the bottom of the tube are collected with a platinum-loop, placed in Canada balsam on a microscopy slide and closed with a cover slip. The preparations are then ready to be submitted to microscopic examination. Other stains may also be used instead of lactophenol-cotton blue. This method is simple, easily performed, and offers good conditions to study these fungi as well as being useful for the diagnosis of the diseases that they cause.

Cohesion decay: quantitative analysis of partial sister chromatid cohesion

Cell division is a highly dynamic process where sister chromatids remain associated with each other from the moment of DNA replication until the later stages of mitosis, giving rise to two daughter cells with equal genomes. The “molecular glue” that links sister DNA molecules is called cohesin, a tripartite ring-like protein complex composed of two Structural Maintenance of Chromosome proteins (Smc1 and Smc3) bridged by a kleisin subunit Rad21/Scc1, that together prevent precocious sister chromatid separation. Accumulating evidence has suggested that cohesion decay may be the cause of segregation errors that underlie certain human pathologies. However it remains to be determined how much cohesin loss abolishes functional sister chromatid cohesion. To answer these questions, we have developed different experimental conditions aiming to titrate the levels of cohesin on mitotic chromosomes in a precise manner. Using these tools, we will determine the minimal amount of cohesin needed to confer functional cohesion. The approaches described here take advantage of a system in Drosophila melanogaster where the Tobacco Etch Virus (TEV) protease can cleave the Rad21 subunit of cohesin leading to precocious sister chromatid separation. Firstly, we tried to express different levels of TEV protease to obtain partial loss of cohesion. However, this approach has failed to produce systematic different levels of sister chromatid separation. Most of the work was therefore focused on a second strategy, for which we established strains with different levels of cohesin sensitive/cohesin resistant to TEV protease. Strains containing different amounts of functional cohesin (TEV resistant) were tested by in vitro cleavage and by in vivo injections in embryos for their ability to promote sister chromatid cohesion. Our results reveal that removal of half of the cohesin complexes does not impair chromosome segregation, implying that chromosome cohesion is less sensitive to cohesin amounts than previously anticipated.

Characterization tests for insulation boards made from corn cob and natural glues

In recent years there has been a growing interest in developing news solutions for more ecologic and efficient construction, including natural, renewable and local materials, thus contributing in the search for more efficient, economic and environmentally friendly construction. Several authors have assessed the possibility of using various agricultural sub products or wastes, as part of the effort of the scientific community to find alternative and more ecologic construction materials. Corn cob is an agricultural waste from a very important worldwide crop. Natural glues are made from natural materials, non-mineral, that can be used as such or after some modifications to achieve the behaviour and performance required. Two examples of these natural glues are casein and wheat flour-based glues that were used in the present study. Boards with different compositions were manufactured, having as variables the type of glue, the dimension of the corn cob particles and the features of the pressing process. The tests boards were characterized with physical and mechanical tests, such as thermal conductivity (λ) with a ISOMET 2104 and 60 mm diameter contact probe, density (ρ) based on EN 1602:2013, surface hardness (SH) with a PCE Shore A durometer, surface resistance (SR) with a PROCEQ PT pendular sclerometer, bending behaviour (σ) based on EN 12089:2013, compression behaviour (σ10) based on EN 826:2013 and resilience (R) based on EN 1094-1:2008, with a Zwick Rowell bending equipment with 2 kN and 50 kN load cells (Fig. 1), dynamic modulus of elasticity (Ed) with a Zeus Resonance Meter equipment (Fig. 5) based on NP EN 14146:2006 and water vapour permeability (δ) based on EN 12086:2013. The various boards produced were characterized according to the tests and the ones with the best results were C8_c8 (casein glue, grain size 2,38-4,76 mm, cold pressing for 8 hours), C8_c4 (casein glue, grain size 2,38-4,76 mm, cold pressing for 4 hours), F8_h0.5 (wheat flour glue, grain size 2,38-4,76 mm, hot pressing for 0,5 hours), FEV8_h0.5 (wheat flour, egg white and vinegar glue, grain size 2,38-4,76 mm, hot pressing for 0,5 hours) and FEVH68_c4 (wheat flour, egg white, vinegar and 6 g of sodium hydroxide glue, grain size 2,38-4,76 mm, cold pressing for 4 hours). Taking into account the various boards produced and respective test results the type of glue and the pressure and pressing time are very important factors which strongly influence the final product. The results obtained confirmed the initial hypotheses that these boards have potential as a thermal and, eventually, acoustic insulation material, to use as coating or intermediate layer on walls, floors or false ceilings. This type of board has a high mechanical resistance when compared with traditional insulating materials.The integrity of these boards seems to be maintained even in higher humidity environments. However, due to biological susceptibility and sensitivity to water, they would be more adequate for application in dry interior conditions.

Analysis and Treatment of a male portrait in oil and a study of the size layer with reconstructions from Vibert’s recipe (1892)

This thesis project concentrated on both the study and treatment of an early 20th century male portrait in oil from Colecção Caixa Geral de Depósitos, Lisbon, Portugal. The portrait of Januário Correia de Almeida, exhibits a tear (approximately 4.0 cm by 2.3 cm) associated with paint loss on the right upper side, where it is possible to observe an unusually thick size layer (approximately 50 microns) and an open weave mesh canvas. Size layers made from animal glue remain subject to severe dimensional changes due to changes in relative humidity (RH), thereby affecting the stability of the painting. In this case, the response to moisture of the size layer is minimal and the painting is largely uncracked with very little active flaking. This suggests that the size layer has undergone pre-treatment to render it unresponsive to moisture or water. Reconstructions based on late nineteenth century recipes using historically appropriate materials are used to explore various options for modifying the characteristics of gelatine, some of which may relate to the Portrait’s size layer. The thesis is separated into two parts: Part 1: Describes the history, condition, materials and techniques of the painting. It also details the treatment of Januário Correia de Almeida as well as the choices made and problems encountered during the treatment. Part 2: Discusses the history of commercial gelatine production, the choice of the appropriate animal source to extract the collagen to produce reconstructions of the portrait’s size layer as well as the characterization of selected reconstructions. The execution of a shallow textured infill led to one publication and one presentation: Abstract accepted for presentation and publication, International Meeting on Retouching of Cultural Heritage (RECH3), Francisco Brites, Leslie Carlyle and Raquel Marques, ‘’Hand building a Low Profile Textured Fill for a Large Loss’’.

Use of licit and illicit drugs at the university of Alfenas

This paper reports the study of drug consumption carried out within the population of undergraduate students from 2 colleges of Alfenas, in the state of Minas Gerais state. Both licit and illicit drugs were studied, including alcohol, tobacco, marijuana, cocaine, heroin, crack, inhalants, glue, tranquilizers, stimulants, and others. METHODOLOGY: The research included a wide bibliographical search and the application of a questionnaire to approximately 23% of the students (total of 6500 students). RESULTS: A total of 1500 students participated in this investigation. The results demonstrated that there was a significant consumption of both licit and illicit drugs. The pattern of drug consumption in the research sample was similar to other investigations conducted in Brazil and in other countries. DISCUSSION: It was observed that 55% of the university students use drugs. However, the most surprising finding was that most of the students (88%) answered "yes" to the inquiry, "Have you already tried any type of drug, including alcohol and cigarettes?" The students revealed that they had taken drugs even prior to the admission to the university. The results suggest clearly that the university environment does not necessarily represent the starting point for student drug consumption.

The perfect paint in modern art conservation: a comparative study of 21st century vinyl emulsions

Contemporary painting places, and will continue to place, several questions about its meaning, its chemical nature, its durability and the best way to preserve it. This research aims at putting together comprehensive data on vinyl based paints, including their components, their properties, their aging behavior and their response to selected cleaning products. In this project degradation mechanisms of vinyl binders and formulations used in the 20th and 21st century were studied. Stability over time of selected vinyl polymers was assessed through natural indoor and artificially aging. The objective was to enhance knowledge and understanding of vinyl emulsion formulations and their performance over time. Overall conservation state of pictorial layers namely, adhesion, cohesion and discoloration of selected case studies from the Portuguese artist Julião Sarmento (b.1948) was correlated with the observed molecular level changes studied in laboratory experiments. Sarmento’s paintings were chosen due to conservation concerns (discoloration) on some of his works from the 90’s. Besides, research was carried out to start increasing the knowledge of what can be expected of PVAc based paints in terms of response to conservation treatments namely, surface cleaning. Artificial aging showed that the most recent formulations which are based on a poly(vinyl acetate), poly(vinyl chloride) and polyethylene terpolymer are less stable when compared to some homopolymer formulations. From the four pigments studied, titanium dioxide rutile and a carbon based black proved to be stabilizers for both types of polymer. The mixture lithopone plus calcium carbonate has showed to have a photocatalytic effect on the binders. The studied paintings showed to be in an overall good state of conservation except for the paintings created in the 90’s with white glue and a mixture of white lithoponeand calcium carbonate. Discoloration of this white paint seems to be irreversible and ongoing and is still a major concern. The disapearance of the plasticizer was the only change detected. The current works created by Sarmento are expected to be more stable as they were painted using the rutile titanium dioxide. Immersion/cleaning tests showed that vinyl based paints can be susceptible to water and organic solvents like ethanol as some evidences point to the removal/diffusion of additives from the paint. The observations made point to the need to further proceed in this research field.

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Primary ciliary dyskinesia (PCD) is an autosomal recessive disease with an incidence estimated between 1:2,000 and 1:40,000. Ciliated epithelia line the airways, nasal and sinus cavities, Eustachian tube and fallopian tubes. Congenital abnormalities of ciliary structure and function impair mucociliary clearance. As a consequence, patients present with chronic sinopulmonary infections, recurrent glue ear and female subfertility. Similarities in the ultrastructure of respiratory cilia, nodal cilia and sperm result in patients with PCD also presenting with male infertility, abnormalities of left-right asymmetry (most commonly situs inversus totalis) and congenital heart disease. Early diagnosis is essential to ensure specialist management of the respiratory and otological complications of PCD. Diagnostic tests focus on analysis of ciliary function and electron microscopy structure. Analysis is technically difficult and labour intensive. It requires expertise for interpretation, restricting diagnosis to specialist centres. Management is currently based on the consensus of experts, and there is a pressing need for randomised clinical trials to inform treatment.

Fibrin sealant for mesh fixation in endoscopic inguinal hernia repair: is there enough evidence for its routine use?

Fibrin sealing has recently evolved as a new technique for mesh fixation in endoscopic inguinal hernia repair. A comprehensive Medline search was carried out evaluating fibrin sealant for mesh fixation, and finally 12 studies were included (3 randomized trials, 3 nonrandomized trials, and 6 case series). The trials were assessed for operative time, seroma formation, recovery time, recurrence rate, and acute and chronic pain.There was a trend toward decreased operative times for fibrin sealing compared with mechanical stapling; however, the results for seroma formation remained contradictory. The most important finding was the reduced postoperative pain. Recovery times were lower after fibrin sealing and the recurrence rates showed no differences.Fibrin sealing for mesh fixation in the endoscopic inguinal hernia surgery is a promising alternative to mechanical stapling, which can be safely applied. As the overall quality of published data remains poor, further well-designed studies are needed until fibrin sealing can replace mechanical stapling as a new standard for mesh fixation.

Muscle recovery after repair of short and long peripheral nerve gaps using fibrin conduits.

Peripheral nerve injuries with loss of nervous tissue are a significant clinical problem and are currently treated using autologous nerve transplants. To avoid the need for donor nerve, which results in additional morbidity such as loss of sensation and scarring, alternative bridging methods have been sought. Recently we showed that an artificial nerve conduit moulded from fibrin glue is biocompatible to nerve regeneration. In this present study, we have used the fibrin conduit or a nerve graft to bridge either a 10 mm or 20 mm sciatic nerve gap and analyzed the muscle recovery in adult rats after 16 weeks. The gastrocnemius muscle weights of the operated side were similar for both gap sizes when treated with nerve graft. In contrast, muscle weight was 48.32 ± 4.96% of the contra-lateral side for the 10 mm gap repaired with fibrin conduit but only 25.20 ± 2.50% for the 20 mm gap repaired with fibrin conduit. The morphology of the muscles in the nerve graft groups showed an intact, ordered structure, with the muscle fibers grouped in fascicles whereas the 20 mm nerve gap fibrin group had a more chaotic appearance. The mean area and diameter of fast type fibers in the 20 mm gap repaired with fibrin conduits were significantly (P<0.01) worse than those of the corresponding 10 mm gap group. In contrast, both gap sizes treated with nerve graft showed similar fiber size. Furthermore, the 10 mm gaps repaired with either nerve graft or fibrin conduit showed similar muscle fiber size. These results indicate that the fibrin conduit can effectively treat short nerve gaps but further modification such as the inclusion of regenerative cells may be required to attain the outcomes of nerve graft for long gaps.

Surgical glues: are they really adhesive?

OBJECTIVE: The aim of this study is to create a standard test to approve the efficacy of a surgical sealant. An industrial test, the bulge-and-blister test, which is very convenient for measuring adhesion energy, is applied to the surgical field to quantify adhesion of bioadhesives. METHODS: Samples were composed of two circular layers of equine pericardium glued by the surgical sealant studied. The sample was fixed to a support with an industrial glue. The support and the bottom layer were perforated in the centre to allow injection of pressurised water. Water was progressively introduced through the hole in the support and the bottom layer to create a blister with constant radius, increasing height and internal pressure during this first step. At a critical pressure, delamination started, the radius and height of the blister increased and the pressure decreased. At this point, the adhesion energy could be determined. The experimental parameters were measured with a pressure sensor and an optical profilometry device for deflection. RESULTS: Adhesion testing was carried out in eight paired equine pericardium samples bonded with a Dermabond cyanoacrylate glue. The average value of the practical adhesion energy is 2.3 Jm(-2) with a standard deviation of 1.5 Jm(-2). CONCLUSION: Application of the bulge-and-blister test to the surgical field was achieved and allowed a quantification of adhesion of a surgical glue. Such information is essential to compare the different surgical glues presently available. The study of the impact of bonding conditions such as pressure, hygrometry or setting conditions will provide a better understanding of the characteristics of adhesion in the surgical field.

A Report from a Local Initiative Concerning Alcohol / Drug Use Among Teenagers 1998-1999

This study was carried out by participants in a North Tipperary Community Services drug/alcohol awareness course. Its objectives were to: assess the level of drug and alcohol awareness among second-level students under the age of 18 years; to find out the extent of under-age drinking;to find out the extent of the use of illegal substances as well as stimulants such as glue and solvents in this age group; and to use this information to develop educational programmes for parents and students. Date was obtained through a survey of 1500 secondary school students in the North Tippeary area. The survey found that, although ilict drug use was very low, abuse of alcohol was quite common.This resource was contributed by The National Documentation Centre on Drug Use.

Mental health and growing up factsheet. Drugs and alcohol - what parents need to know.

Information about drugs and alcohol - what parents need to know: information for parents, carers and anyone who works with young people. About this leaflet This is one in a series of leaflets for parents, teachers and young people entitled Mental Health and Growing Up. These leaflets aim to provide practical, up-to-date information about mental health problems (emotional, behavioural and psychiatric disorders) that can affect children and young people. This leaflet offers practical advice for parents, teachers and carers who are worried that a young person is misusing drugs or alcohol. Why do I need to know about a young person using drugs or alcohol? Many young people smoke, drink alcohol and may try drugs. It is important you are aware of this and do not ignore it as a time when they are just having fun or experimenting. It doesnââ,‰"¢t take much for the young people to soon lose control and to need help to recover from this problem. How common is it? By the age of 16, up to half of young people have tried an illegal drug. Young people are trying drugs earlier and more are drinking alcohol. What are the different types of drugs which cause problems? The most commonly used, readily available and strongly addictive drugs are tobacco and alcohol. There are numerous others that can be addictive. Alcohol and cannabis are sometimes seen as ââ,¬Ëogatewayââ,‰"¢ drugs that lead to the world of other drugs like cocaine and heroin. Drugs are also classed as ââ,¬Ëolegalââ,‰"¢ andââ,¬Ëoillegalââ,‰"¢. The obviously illegal drugs include cannabis (hash), speed (amphetamines), ecstasy (E), cocaine and heroin. Using ââ,¬Ëolegalââ,‰"¢ drugs (like cigarettes, alcohol, petrol, glue) does not mean they are safe or allowed to be misused. It just means they may be bought or sold for specific purposes and are limited to use by specific age groups. There are clear laws regarding alcohol and young people. For more detailed information on various drugs, their side-effects and the law, see ââ,¬ËoFurther Informationââ,‰"¢ at the end of the factsheet. Why do young people use drugs or alcohol? Young people may try or use drugs or alcohol for various reasons. They may do it for fun, because they are curious, or to be like their friends. Some are experimenting with the feeling of intoxication. Sometimes they use it to cope with difficult situations or feelings of worry and low mood. A young person is more likely to try or use drugs or alcohol if they hang out or stay with friends or family who use them. What can be the problems related to using drugs or alcohol? Drugs and alcohol can have different effects on different people. In young people especially the effects can be unpredictable and potentially dangerous. Even medications for sleep or painkillers can be addictive and harmful if not used the way they are prescribed by a doctor. Drugs and alcohol can damage health. Sharing needles or equipment can cause serious infections, such as HIV and hepatitis. Accidents, arguments and fights are more likely after drinking and drug use. Young people are more likely to engage in unprotected sex when using drugs. Using drugs can lead to serious mental illnesses, such as psychosis and depression. When does it become addiction or problem? It is very difficult to know when exactly using drugs or alcohol is more than just ââ,¬Ëocasualââ,‰"¢. Addiction becomes more obvious when the young person spends most of their time thinking about, looking for or using drugs. Drugs or alcohol then become the focus of the young personââ,‰"¢s life. They ignore their usual work, such as not doing their schoolwork, or stop doing their usual hobbies/sports such as dancing or football. How do I know if there is a problem or addiction? Occasional use can be very difficult to detect. If the young person is using on a regular basis, their behaviour often changes. Look for signs such as: ïâ?s§ unexplained moodiness ïâ?s§ behaviour that is ââ,¬Ëoout of character' ïâ?s§ loss of interest in school or friends ïâ?s§ unexplained loss of clothes or money ïâ?s§ unusual smells and items like silver foil, needle covers. Remember, the above changes can also mean other problems, such as depression, rather than using drugs. What do I do if I am worried? If you suspect young person is using drugs, remember some general rules. ïâ?s§ Pay attention to what the child is doing, including schoolwork, friends and leisure time. ïâ?s§ Learn about the effects of alcohol and drugs (see websites listed below). ïâ?s§ Listen to what the child says about alcohol and drugs, and talk about it with them. ïâ?s§ Encourage the young person to be informed and responsible about drugs and alcohol. ïâ?s§ Talk to other parents, friends or teachers about drugs - the facts and your fears and seek help. If someone in the family or close friend is using drugs or alcohol, it is important that they seek help too. It may be hard to expect the young person to give up, especially if a parent or carer is using it too. My child is abusing drugs. What do I do? ïâ?s§ If your child is using drugs or alcohol, seek help. ïâ?s§ Do stay calm and make sure of facts. ïâ?s§ Don't give up on them, get into long debates or arguments when they are drunk, stoned or high. ïâ?s§ Donââ,‰"¢t be angry or blame themââ,‰?othey need your help and trust to make journey of recovery. Where can I get help? You can talk in confidence to a professional like your GP or practice nurse, a local drug project or your local child and adolescent mental health. They can refer your child to relevant services and they will be able to offer you advice and support. You may also be able to seek help through a school nurse, teacher or social worker. You can find this information from your local area telephone book or council website, or ask for the address from your health centre. [For the full factsheet, click on the link above]This resource was contributed by The National Documentation Centre on Drug Use.

The pressure cooker technique for the treatment of brain AVMs.

Arteriovenous malformations (AVMs) may be cured by injecting liquid embolic agents such as Onyx. Reflux, however, can sometimes be difficult to control and may jeopardize a complete embolization. The pressure cooker technique (PCT) was designed to create an anti-reflux plug by trapping the detachable part of an Onyx-compatible microcatheter with coils and glue in order to obtain wedge-flow conditions, thereby enabling a better understanding of macrofistulous AVMs and a more comprehensive, forceful and controlled Onyx embolization. The PCT might enlarge the range of AVMs amenable to endovascular cure. Three illustrative cases are presented.