Academic literature on the topic 'Lamas activadas'

The onset of puberty in mammals involves an increase in the pulsatile release of GNRH and LH. The KISS1 gene is essential for pubertal development, and its product, kisspeptin, stimulates the release of LH. The objective of this study was to determine the effects of kisspeptin in the hypothalamic–adenohypophyseal–gonadal axis of prepubertal ewe lambs. Ewe lambs (28 weeks of age) were treated intravenously with saline (control, n=6) or kisspeptin (20 μg kisspeptin; n=6) every hour for 24 h. Kisspeptin stimulated pulse-like release of LH within 15 min following injections, and increased the frequency and amplitude of LH pulses, and mean circulating concentrations of LH and estradiol. A surge-like release of LH was observed in four kisspeptin-treated lambs beginning 17 h after the onset of treatment, and all four lambs had elevated circulating concentrations of progesterone within 5 days post-treatment. However, circulating concentrations of progesterone decreased within 2 days after the initial rise in three of the four ewe lambs, indicating that induced luteal activity was of short duration. The proportion of lambs that were pubertal (defined by circulating concentrations of progesterone above 1 ng/ml for at least 7 days) by 35 weeks of age (8/11) and the mean age at puberty (32±1 weeks) for those reaching puberty within the experimental period did not differ between treatments. Results support a role for kisspeptin in the activation of the hypothalamic–adenohypophyseal axis leading to the onset of puberty in ewe lambs.

Abstract1. Aspects of the ewe which influence the lamb. Lambs were removed from their mothers at birth and tested under one of seven conditions : (1) with the dam in her pen, or, in a circular arena, (2) in the presence of a stationary model ewe, (3) with the same model, but moving, (4) in the presence of a large, headless and legless moving object, (5) with stimulation by the sound of recorded bleats, (6) with tactile stimulation or (7) with no stimulation. Indices of responsiveness included movements of righting and standing, approach to the model, bleating and nosing of the model or the arena. Results showed that lambs tested with the stationary model stood most slowly whereas the presence of the moving model ewe was associated with rapid standing. The groups with no experimental stimulation at all, or with stimulation by the sound of recorded bleats, also stood rapidly. Bleating of the lambs was most prevalent in the group with no stimulation at all. Lambs presented with moving models approached them more rapidly and nosed them more than did those tested with the stationary model. More than any others, lambs in the "stationary model" group were quiescent for long periods. Lambs tested in the presence of their mothers and those given tactile stimulation were consistently low in the rank order for all indices of response; in particular they stood more slowly and bleated less than groups presented with moving models. It is concluded that the dam is a composite stimulus for her lamb; she activates it when she moves but also elicits responses which reduce its early activity. 2. Aspects of the lamb which attract the ewe. Ninety Merino ewes, from each of which the lamb had been removed at birth, were tested in their own pens under one of the following conditions: (i) with their own lambs; (ii) with a warm, moving lamb model soaked in amniotic fluid and accompanied by lamb bleats, or with the same model but (iii) without movement; (iv) without warmth; (v) without bleats or (vi) without amniotic fluid. A seventh group was tested with a white bowl of warm amniotic fluid, also moving and accompanied by lamb bleats. The ewes approached their own lambs and were much more attentive to them, than to any of the models. The model which received the least attention was that (vi) with no amniotic fluid, while the 'model' which received the most was (vii) the white bowl containing amniotic fluid.

Reduced mitochondrial oxidative phosphorylation, via activation of adenylate kinase and the resulting exponential rise in the cellular AMP/ATP ratio, appears to be a critical factor underlying O2 sensing in many chemoreceptive tissues in mammals. The elevated AMP/ATP ratio, in turn, activates key enzymes that are involved in physiologic adjustments that tend to balance ATP supply and demand. An example is the conversion of AMP to adenosine via 5′-nucleotidase and the resulting activation of adenosine A2A receptors, which are involved in acute oxygen sensing by both carotid bodies and the brain. In fetal sheep, A2A receptors associated with carotid bodies trigger hypoxic cardiovascular chemoreflexes, while central A2A receptors mediate hypoxic inhibition of breathing and rapid eye movements. A2A receptors are also involved in hypoxic regulation of fetal endocrine systems, metabolism, and vascular tone. In developing lambs, A2A receptors play virtually no role in O2 sensing by the carotid bodies, but brain A2A receptors remain critically involved in the roll-off ventilatory response to hypoxia. In adult mammals, A2A receptors have been implicated in O2 sensing by carotid glomus cells, while central A2A receptors likely blunt hypoxic hyperventilation. In conclusion, A2A receptors are crucially involved in the transduction mechanisms of O2 sensing in fetal carotid bodies and brains. Postnatally, central A2A receptors remain key mediators of hypoxic respiratory depression, but they are less critical for O2 sensing in carotid chemoreceptors, particularly in developing lambs.

Early work in ewes provided a wealth of information on the physiological regulation of pulsatile gonadotropin-releasing hormone (GnRH) secretion by internal and external inputs. Identification of the neural systems involved, however, was limited by the lack of information on neural mechanisms underlying generation of GnRH pulses. Over the last decade, considerable evidence supported the hypothesis that a group of neurons in the arcuate nucleus that contain kisspeptin, neurokinin B and dynorphin (KNDy neurons) are responsible for synchronizing secretion of GnRH during each pulse in ewes. In this review, we describe our current understanding of the neural systems mediating the actions of ovarian steroids and three external inputs on GnRH pulsatility in light of the hypothesis that KNDy neurons play a key role in GnRH pulse generation. In breeding season adults, estradiol (E2) and progesterone decrease GnRH pulse amplitude and frequency, respectively, by actions on KNDy neurons, with E2decreasing kisspeptin and progesterone increasing dynorphin release onto GnRH neurons. In pre-pubertal lambs, E2inhibits GnRH pulse frequency by decreasing kisspeptin and increasing dynorphin release, actions that wane as the lamb matures to allow increased pulsatile GnRH secretion at puberty. Less is known about mediators of undernutrition and stress, although some evidence implicates kisspeptin and dynorphin, respectively, in the inhibition of GnRH pulse frequency by these factors. During the anoestrus, inhibitory photoperiod acting via melatonin activates A15 dopaminergic neurons that innervate KNDy neurons; E2increases dopamine release from these neurons to inhibit KNDy neurons and suppress the frequency of kisspeptin and GnRH release.

Cyborgs already walk among us. (“Cures to Come” 76) This essay was begun as a reaction to a Hallmark Hall of Fame television movie called Sweet Nothing in My Ear (2008), which follows the lives of two parents, Dan, who is hearing (played by Jeff Daniels), and Laura, who is deaf (Marlee Matlin), as they struggle to make a decision about whether or not to give their 11-year-old son, Adam (late-deafened), a cochlear implant. Dan and Laura represent different perspectives, hearing and deaf perspectives. The film dramatizes the parents’ conflict and negotiation, exposing audiences to both sides of the cochlear implant debate, albeit in a fairly simplistic way. Nevertheless, it represents the lives of deaf people and gives voice to debates about cochlear implants with more accuracy and detail than most film and television dramas. One of the central scenes in the film is what I call the “activation scene”, quite common to cochlear implant narratives. In the scene, the protagonists witness a child having his implant activated or turned on. The depiction is reminiscent of the WATER scene in the film about Helen Keller, The Miracle Worker, employing a sentimental visual rhetoric. First, the two parents are shown seated near the child, clasping their hands as if in prayer. The audiologist, wielder of technology and therefore clearly the authority figure in the scene, types away furiously on her laptop. At the moment of being “turned on,” the child suddenly “hears” his father calling “David! David!” He gazes angelically toward heaven as piano music plays plaintively in the background. The parents all but fall to their knees and the protagonist of the film, Dan, watching through a window, weeps. It is a scene of cure, of healing, of “miracle,” a hyper-sentimentalised portrait of what is in reality often a rather anti-climactic event. It was certainly anti-climactic in my son, Michael’s case. I was taken aback by how this scene was presented and dismayed overall at some of the inaccuracies, small though they were, in the portrayal of cochlear implants in this film. It was, after all, according to the Nielsen ratings, seen by 8 million people. I began to wonder what kinds of misconceptions my son was going to face when he met people whose only exposure to implants was through media representations. Spurred by this question, I started to research other recent portrayals of people with implants on U.S. television in the past ten years, to see how cochlear implant (hereafter referred to as CI) identity has been portrayed by American media. For most of American history, deaf people have been portrayed in print and visual media as exotic “others,” and have long been the subject of an almost morbid cultural fascination. Christopher Krentz suggests that, particularly in the nineteenth century, scenes pairing sentimentality and deafness repressed an innate, Kristevan “abject” revulsion towards deaf people. Those who are deaf highlight and define, through their ‘lack’, the “unmarked” body. The fact of their deafness, understood as lack, conjures up an ideal that it does not attain, the ideal of the so-called “normal” or “whole” body. In recent years, however, the figure of the “deaf as Other” in the media, has shifted from what might be termed the “traditionally” deaf character, to what Brenda Jo Brueggeman (in her recent book Deaf Subjects: Between Identities and Places), calls “the new deaf cyborg” or the deaf person with a cochlear implant (4). N. Katharine Hailes states that cyborgs are now “the stage on which are performed contestations about the body boundaries that have often marked class, ethnic, and cultural differences” (85). In this essay, I claim that the character with a CI, as portrayed in the media, is now not only a strange, “marked” “Other,” but is also a screen upon which viewers project anxieties about technology, demonstrating both fascination fear. In her book, Brueggeman issues a call to action, saying that Deaf Studies must now begin to examine what she calls “implanting rhetorics,” or “the rhetorical relationships between our technologies and our identity” and therefore needs to attend to the construction of “the new deaf cyborg” (18). This short study will serve, I hope, as both a response to that injunction and as a jumping-off point for more in-depth studies of the construction of the CI identity and the implications of these constructions. First, we should consider what a cochlear implant is and how it functions. The National Association of the Deaf in the United States defines the cochlear implant as a device used to help the user perceive sound, i.e., the sensation of sound that is transmitted past the damaged cochlea to the brain. In this strictly sensorineural manner, the implant works: the sensation of sound is delivered to the brain. The stated goal of the implant is for it to function as a tool to enable deaf children to develop language based on spoken communication. (“NAD Position”) The external portion of the implant consists of the following parts: a microphone, which picks up sound from the environment, which is contained in the behind-the-ear device that resembles the standard BTE hearing aid; in this “hearing aid” there is also a speech processor, which selects and arranges sounds picked up by the microphone. The processor transmits signals to the transmitter/receiver, which then converts them into electric impulses. Part of the transmitter sits on the skin and attaches to the inner portion of the transmitter by means of a magnet. The inner portion of the receiver/stimulator sends the impulses down into the electrode array that lies inside the cochlea, which in turn stimulates the auditory nerve, giving the brain the impression of sound (“Cochlear Implants”). According to manufacturer’s statistics, there are now approximately 188,000 people worldwide who have obtained cochlear implants, though the number of these that are in use is not known (Nussbaum). That is what a cochlear implant is. Before we can look at how people with implants are portrayed in the media, before we examine constructions of identity, perhaps we should first ask what constitutes a “real” CI identity? This is, of course, laughable; pinning down a homogeneous CI identity is no more likely than finding a blanket definition of “deaf identity.” For example, at this point in time, there isn’t even a word or term in American culture for someone with an implant. I struggle with how to phrase it in this essay - “implantee?” “recipient?” - there are no neat labels. In the USA you can call a person deaf, Deaf (the “D” representing a specific cultural and political identity), hearing impaired, hard of hearing, and each gradation implies, for better or worse, some kind of subject position. There are no such terms for a person who gets an implant. Are people with implants, as suggested above, just deaf? Deaf? Are they hard of hearing? There is even debate in the ASL community as to what sign should be used to indicate “someone who has a cochlear implant.” If a “CI identity” cannot be located, then perhaps the rhetoric that is used to describe it may be. Paddy Ladd, in Understanding Deaf Culture, does a brilliant job of exploring the various discourses that have surrounded deaf culture throughout history. Stuart Blume borrows heavily from Ladd in his “The Rhetoric and Counter-Rhetoric of a 'Bionic' Technology”, where he points out that an “essential and deliberate feature” of the history of the CI from the 60s onward, was that it was constructed in an overwhelmingly positive light by the mass media, using what Ladd calls the “medical” rhetorical model. That is, that the CI is a kind of medical miracle that promised to cure deafness. Within this model one may find also the sentimental, “missionary” rhetoric that Krentz discusses, what Ladd claims is a revival of the evangelism of the nineteenth-century Oralist movement in America. Indeed, newspaper articles in the 1980s and 90s hailed the implant as a “breakthrough”, a “miracle”; even a quick survey of headlines shows evidence of this: “Upton Boy Can Hear at Last!”, “Girl with a New Song in Her Heart”, “Children Head Queue for Bionic Ears” (Lane). As recently as January 2010, an issue of National Geographic featured on its cover the headline Merging Man and Machine: The Bionic Age. Sure enough, the second photograph in the story is of a child’s bilateral cochlear implant, with the caption “within months of the surgery (the child) spoke the words his hearing parents longed for: Mama and Dada.” “You’re looking at a real bionic kid,” says Johns Hopkins University surgeon John Niparko, proudly (37). To counter this medical/corporate rhetoric of cure, Ladd and Blume claim, the deaf community devised a counter-rhetoric, a discourse in which the CI is not cast in the language of miracle and life, but instead in terms of death, mutilation, and cultural oppression. Here, the implant is depicted as the last in a long line of sadistic experiments using the deaf as guinea pigs. Often the CI is framed in the language of Nazism and genocide as seen in the title of an article in the British Deaf News: “Cochlear Implants: Oralism’s Final Solution.” So, which of these two “implanting rhetorics” is most visible in the current construction of the CI in American television? Is the CI identity presented by rendering people with CIs impossibly positive, happy characters? Is it delineated using the metaphors of the sentimental, of cure, of miracle? Or is the CI identity constructed using the counter-rhetorical references to death, oppression and cultural genocide? One might hypothesize that television, like other media, cultivating as it does the values of the hearing hegemony, would err on the side of promulgating the medicalised, positivist rhetoric of the “cure” for deafness. In an effort to find out, I conducted a general survey of American television shows from 2000 to now that featured characters with CIs. I did not include news shows or documentaries in my survey. Interestingly, some of the earliest television portrayals of CIs appeared in that bastion of American sentimentality, the daytime soap opera. In 2006, on the show “The Young and the Restless”, a “troubled college student who contracted meningitis” received an implant, and in 2007 “All My Children” aired a story arc about a “toddler who becomes deaf after a car crash.” It is interesting to note that both characters were portrayed as “late-deafened”, or suddenly inflicted with the loss of a sense they previously possessed, thus avoiding any whiff of controversy about early implantation. But one expects a hyper-sentimentalised portrayal of just about everything in daytime dramas like this. What is interesting is that when people with CIs have appeared on several “reality” programs, which purport to offer “real,” unadulterated glimpses into people’s lives, the rhetoric is no less sentimentalized than the soaps (perhaps because these shows are no less fabricated). A good example of this is the widely watched and, I think, ironically named show “True Life” which appears on MTV. This is a series that claims to tell the “remarkable real-life stories of young people and the unusual subcultures they inhabit.” In episode 42, “ True Life: I’m Deaf”, part of the show follows a young man, Chris, born deaf and proud of it (his words), who decides to get a cochlear implant because he wants to be involved in the hearing world. Through an interpreter Chris explains that he wants an implant so he can communicate with his friends, talk with girls, and ultimately fulfill his dreams of having a job and getting married (one has to ask: are these things he can’t do without an implant?). The show’s promo asks “how do you go from living a life in total silence to fully understanding the spoken language?” This statement alone contains two elements common to the “miracle” rhetoric, first that the “tragic” deaf victim will emerge from a completely lonely, silent place (not true; most deaf people have some residual hearing, and if you watch the show you see Chris signing, “speaking” voluminously) to seamlessly, miraculously, “fully” joining and understanding the hearing world. Chris, it seems, will only come into full being when he is able to join the hearing world. In this case, the CI will cure what ails him. According to “True Life.” Aside from “soap opera” drama and so-called reality programming, by far the largest dissemination of media constructions of the CI in the past ten years occurred on top-slot prime-time television shows, which consist primarily of the immensely popular genre of the medical and police procedural drama. Most of these shows have at one time or another had a “deaf” episode, in which there is a deaf character or characters involved, but between 2005 and 2008, it is interesting to note that most, if not all of the most popular of these have aired episodes devoted to the CI controversy, or have featured deaf characters with CIs. The shows include: CSI (both Miami and New York), Cold Case, Law and Order (both SVU and Criminal Intent), Scrubs, Gideon’s Crossing, and Bones. Below is a snippet of dialogue from Bones: Zach: {Holding a necklace} He was wearing this.Angela: Catholic boy.Brennan: One by two forceps.Angela {as Brennan pulls a small disc out from behind the victim’s ear} What is that?Brennan: Cochlear implant. Looks like the birds were trying to get it.Angela: That would set a boy apart from the others, being deaf.(Bones, “A Boy in the Tree”, 1.3, 2005) In this scene, the forensics experts are able to describe significant points of this victim’s identity using the only two solid artifacts left in the remains, a crucifix and a cochlear implant. I cite this scene because it serves, I believe, as a neat metaphor for how these shows, and indeed television media in general, are, like the investigators, constantly engaged in the business of cobbling together identity: in this particular case, a cochlear implant identity. It also shows how an audience can cultivate or interpret these kinds of identity constructions, here, the implant as an object serves as a tangible sign of deafness, and from this sign, or clue, the “audience” (represented by the spectator, Angela) immediately infers that the victim was lonely and isolated, “set apart from the others.” Such wrongheaded inferences, frivolous as they may seem coming from the realm of popular culture, have, I believe, a profound influence on the perceptions of larger society. The use of the CI in Bones is quite interesting, because although at the beginning of the show the implant is a key piece of evidence, that which marks and identifies the dead/deaf body, the character’s CI identity proves almost completely irrelevant to the unfolding of the murder-mystery. The only times the CI character’s deafness is emphasized are when an effort is made to prove that the he committed suicide (i.e., if you’re deaf you are therefore “isolated,” and therefore you must be miserable enough to kill yourself). Zak, one of the forensics officers says, “I didn’t talk to anyone in high school and I didn’t kill myself” and another officer comments that the boy was “alienated by culture, by language, and by his handicap” (odd statements, since most deaf children with or without implants have remarkably good language ability). Also, in another strange moment, the victim’s ambassador/mother shows a video clip of the child’s CI activation and says “a person who lived through this miracle would never take his own life” (emphasis mine). A girlfriend, implicated in the murder (the boy is killed because he threatened to “talk”, revealing a blackmail scheme), says “people didn’t notice him because of the way he talked but I liked him…” So at least in this show, both types of “implanting rhetoric” are employed; a person with a CI, though the recipient of a “miracle,” is also perceived as “isolated” and “alienated” and unfortunately, ends up dead. This kind of rather negative portrayal of a person with a CI also appears in the CSI: New York episode ”Silent Night” which aired in 2006. One of two plot lines features Marlee Matlin as the mother of a deaf family. At the beginning of the episode, after feeling some strange vibrations, Matlin’s character, Gina, checks on her little granddaughter, Elizabeth, who is crying hysterically in her crib. She finds her daughter, Alison, dead on the floor. In the course of the show, it is found that a former boyfriend, Cole, who may have been the father of the infant, struggled with and shot Alison as he was trying to kidnap the baby. Apparently Cole “got his hearing back” with a cochlear implant, no longer considered himself Deaf, and wanted the child so that she wouldn’t be raised “Deaf.” At the end of the show, Cole tries to abduct both grandmother and baby at gunpoint. As he has lost his external transmitter, he is unable to understand what the police are trying to tell him and threatens to kill his hostages. He is arrested in the end. In this case, the CI recipient is depicted as a violent, out of control figure, calmed (in this case) only by Matlin’s presence and her ability to communicate with him in ASL. The implication is that in getting the CI, Cole is “killing off” his Deaf identity, and as a result, is mentally unstable. Talking to Matlin, whose character is a stand-in for Deaf culture, is the only way to bring him back to his senses. The October 2007 episode of CSI: Miami entitled “Inside-Out” is another example of the counter-rhetoric at work in the form of another implant corpse. A police officer, trying to prevent the escape of a criminal en route to prison, thinks he has accidentally shot an innocent bystander, a deaf woman. An exchange between the coroner and a CSI goes as follows: (Alexx Woods): “This is as innocent as a victim gets.”(Calleigh Duquesne): “How so?”AW: Check this out.”CD: “I don’t understand. Her head is magnetized? Steel plate?”AW: “It’s a cochlear implant. Helps deaf people to receive and process speech and sounds.”(CSI dramatization) AW VO: “It’s surgically implanted into the inner ear. Consists of a receiver that decodes and transmits to an electrode array sending a signal to the brain.”CD: “Wouldn’t there be an external component?”AW: “Oh, she must have lost it before she was shot.”CD: “Well, that explains why she didn’t get out of there. She had no idea what was going on.” (TWIZ) Based on the evidence, the “sign” of the implant, the investigators are able to identify the victim as deaf, and they infer therefore that she is innocent. It is only at the end of the program that we learn that the deaf “innocent” was really the girlfriend of the criminal, and was on the scene aiding in his escape. So she is at first “as innocent” as they come, and then at the end, she is the most insidious of the criminals in the episode. The writers at least provide a nice twist on the more common deaf-innocent stereotype. Cold Case showcased a CI in the 2008 episode “Andy in C Minor,” in which the case of a 17-year-old deaf boy is reopened. The boy, Andy, had disappeared from his high school. In the investigation it is revealed that his hearing girlfriend, Emma, convinced him to get an implant, because it would help him play the piano, which he wanted to do in order to bond with her. His parents, deaf, were against the idea, and had him promise to break up with Emma and never bring up the CI again. His body is found on the campus, with a cochlear device next to his remains. Apparently Emma had convinced him to get the implant and, in the end, Andy’s father had reluctantly consented to the surgery. It is finally revealed that his Deaf best friend, Carlos, killed him with a blow to the back of the head while he was playing the piano, because he was “afraid to be alone.” This show uses the counter-rhetoric of Deaf genocide in an interesting way. In this case it is not just the CI device alone that renders the CI character symbolically “dead” to his Deaf identity, but it leads directly to his being literally executed by, or in a sense, excommunicated from, Deaf Culture, as it is represented by the character of Carlos. The “House Divided” episode of House (2009) provides the most problematic (or I should say absurd) representation of the CI process and of a CI identity. In the show, a fourteen-year-old deaf wrestler comes into the hospital after experiencing terrible head pain and hearing “imaginary explosions.” Doctors Foreman and Thirteen dutifully serve as representatives of both sides of the “implant debate”: when discussing why House hasn’t mocked the patient for not having a CI, Thirteen says “The patient doesn’t have a CI because he’s comfortable with who he is. That’s admirable.” Foreman says, “He’s deaf. It’s not an identity, it’s a disability.” 13: “It’s also a culture.” F: “Anything I can simulate with $3 earplugs isn’t a culture.” Later, House, talking to himself, thinks “he’s going to go through life deaf. He has no idea what he’s missing.” So, as usual, without permission, he orders Chase to implant a CI in the patient while he is under anesthesia for another procedure (a brain biopsy). After the surgery the team asks House why he did it and he responds, “Why would I give someone their hearing? Ask God the same question you’d get the same answer.” The shows writers endow House’s character, as they usually do, with the stereotypical “God complex” of the medical establishment, but in doing also they play beautifully into the Ladd and Blume’s rhetoric of medical miracle and cure. Immediately after the implant (which the hospital just happened to have on hand) the incision has, miraculously, healed overnight. Chase (who just happens to be a skilled CI surgeon and audiologist) activates the external processor (normally a months-long process). The sound is overwhelming, the boy hears everything. The mother is upset. “Once my son is stable,” the mom says, “I want that THING out of his head.” The patient also demands that the “thing” be removed. Right after this scene, House puts a Bluetooth in his ear so he can talk to himself without people thinking he’s crazy (an interesting reference to how we all are becoming cyborgs, more and more “implanted” with technology). Later, mother and son have the usual touching sentimental scene, where she speaks his name, he hears her voice for the first time and says, “Is that my name? S-E-T-H?” Mom cries. Seth’s deaf girlfriend later tells him she wishes she could get a CI, “It’s a great thing. It will open up a whole new world for you,” an idea he rejects. He hears his girlfriend vocalize, and asks Thirteen if he “sounds like that.” This for some reason clinches his decision about not wanting his CI and, rather than simply take off the external magnet, he rips the entire device right out of his head, which sends him into shock and system failure. Ultimately the team solves the mystery of the boy’s initial ailment and diagnoses him with sarcoidosis. In a final scene, the mother tells her son that she is having them replace the implant. She says it’s “my call.” This show, with its confusing use of both the sentimental and the counter-rhetoric, as well as its outrageous inaccuracies, is the most egregious example of how the CI is currently being constructed on television, but it, along with my other examples, clearly shows the Ladd/Blume rhetoric and counter rhetoric at work. The CI character is on one hand portrayed as an innocent, infantilized, tragic, or passive figure that is the recipient of a medical miracle kindly urged upon them (or forced upon them, as in the case of House). On the other hand, the CI character is depicted in the language of the counter-rhetoric: as deeply flawed, crazed, disturbed or damaged somehow by the incursions onto their Deaf identity, or, in the worst case scenario, they are dead, exterminated. Granted, it is the very premise of the forensic/crime drama to have a victim, and a dead victim, and it is the nature of the police drama to have a “bad,” criminal character; there is nothing wrong with having both good and bad CI characters, but my question is, in the end, why is it an either-or proposition? Why is CI identity only being portrayed in essentialist terms on these types of shows? Why are there no realistic portrayals of people with CIs (and for that matter, deaf people) as the richly varied individuals that they are? These questions aside, if these two types of “implanting rhetoric”, the sentimentalised and the terminated, are all we have at the moment, what does it mean? As I mentioned early in this essay, deaf people, along with many “others,” have long helped to highlight and define the hegemonic “norm.” The apparent cultural need for a Foucauldian “marked body” explains not only the popularity of crime dramas, but it also could explain the oddly proliferant use of characters with cochlear implants in these particular shows. A person with an implant on the side of their head is definitely a more “marked” body than the deaf person with no hearing aid. The CI character is more controversial, more shocking; it’s trendier, “sexier”, and this boosts ratings. But CI characters are, unlike their deaf predecessors, now serving an additional cultural function. I believe they are, as I claim in the beginning of this essay, screens upon which our culture is now projecting repressed anxieties about emergent technology. The two essentialist rhetorics of the cochlear implant, the rhetoric of the sentimental, medical model, and the rhetoric of genocide, ultimately represent our technophilia and our technophobia. The CI character embodies what Debra Shaw terms a current, “ontological insecurity that attends the interface between the human body and the datasphere” (85). We are growing more nervous “as new technologies shape our experiences, they blur the lines between the corporeal and incorporeal, between physical space and virtual space” (Selfe). Technology either threatens the integrity of the self, “the coherence of the body” (we are either dead or damaged) or technology allows us to transcend the limitations of the body: we are converted, “transformed”, the recipient of a happy modern miracle. In the end, I found that representations of CI on television (in the United States) are overwhelmingly sentimental and therefore essentialist. It seems that the conflicting nineteenth century tendency of attraction and revulsion toward the deaf is still, in the twenty-first century, evident. We are still mired in the rhetoric of “cure” and “control,” despite an active Deaf counter discourse that employs the language of the holocaust, warning of the extermination of yet another cultural minority. We are also daily becoming daily more “embedded in cybernetic systems,” with our laptops, emails, GPSs, PDAs, cell phones, Bluetooths, and the likes. We are becoming increasingly engaged in a “necessary relationship with machines” (Shaw 91). We are gradually becoming no longer “other” to the machine, and so our culturally constructed perceptions of ourselves are being threatened. In the nineteenth century, divisions and hierarchies between a white male majority and the “other” (women, African Americans, immigrants, Native Americans) began to blur. Now, the divisions between human and machine, as represented by a person with a CI, are starting to blur, creating anxiety. Perhaps this anxiety is why we are trying, at least in the media, symbolically to ‘cure’ the marked body or kill off the cyborg. Future examinations of the discourse should, I believe, use these media constructions as a lens through which to continue to examine and illuminate the complex subject position of the CI identity, and therefore, perhaps, also explore what the subject position of the post/human identity will be. References "A Boy in a Tree." Patrick Norris (dir.), Hart Hanson (by), Emily Deschanel (perf.). Bones, Fox Network, 7 Sep. 2005. “Andy in C Minor.” Jeannete Szwarc (dir.), Gavin Harris (by), Kathryn Morris (perf.). Cold Case, CBS Network, 30 March 2008. Blume, Stuart. “The Rhetoric and Counter Rhetoric of a “Bionic” Technology.” Science, Technology and Human Values 22.1 (1997): 31-56. Brueggemann, Brenda Jo. Deaf Subjects: Between Identities and Places. New York: New York UP, 2009. “Cochlear Implant Statistics.” ASL-Cochlear Implant Community. Blog. Citing Laurent Le Clerc National Deaf Education Center. Gallaudet University, 18 Mar. 2008. 29 Apr. 2010 ‹http:/ /aslci.blogspot.com/2008/03/cochlear-implant-statistics.html›. “Cures to Come.” Discover Presents the Brain (Spring 2010): 76. Fischman, Josh. “Bionics.” National Geographic Magazine 217 (2010). “House Divided.” Greg Yaitanes (dir.), Matthew V. Lewis (by), Hugh Laurie (perf.). House, Fox Network, 22 Apr. 2009. “Inside-Out.” Gina Lamar (dir.), Anthony Zuiker (by), David Caruso (perf.). CSI: Miami, CBS Network, 8 Oct. 2007. Krentz, Christopher. Writing Deafness: The Hearing Line in Nineteenth-Century American Literature. Chapel Hill: UNC P, 2007. Ladd, Paddy. Understanding Deaf Culture: In Search of Deafhood. Clevedon, UK: Multilingual Matters Limited, 2002. Lane, Harlan. A Journey Into the Deaf-World. San Diego: DawnSignPress, 1996. “NAD Position Statement on the Cochlear Implant.” National Association of the Deaf. 6 Oct. 2000. 29 April 2010 ‹http://www.nad.org/issues/technology/assistive-listening/cochlear-implants›. Nussbaum, Debra. “Manufacturer Information.” Cochlear Implant Information Center. National Deaf Education Center. Gallaudet University. 29 Apr. 2010 < http://clerccenter.gallaudet.edu >. Shaw, Debra. Technoculture: The Key Concepts. Oxford: Berg, 2008. “Silent Night.” Rob Bailey (dir.), Anthony Zuiker (by), Gary Sinise (perf.). CSI: New York, CBS Network, 13 Dec. 2006. “Sweet Nothing in My Ear.” Joseph Sargent (dir.), Stephen Sachs (by), Jeff Daniels (perf.). Hallmark Hall of Fame Production, 20 Apr. 2008. TWIZ TV scripts. CSI: Miami, “Inside-Out.” “What Is the Surgery Like?” FAQ, University of Miami Cochlear Implant Center. 29 Apr. 2010 ‹http://cochlearimplants.med.miami.edu/faq/index.asp›.

Mestrado em Engenharia Química
No decurso da procura activa pela rentabilidade de resíduos sólidos, provenientes das etapas de produção da indústria de pasta e papel, surge a perspectiva para a valorização energética da fracção celulósica de lamas primárias, para a produção de biocombustíveis de segunda geração. Com efeito, a partir deste trabalho pretendeu estudar-se o desempenho da hidrólise enzimática nas lamas primárias e, aplicando um pré-tratamento hiperbárico, averiguar a influência real do mesmo no desenrolar dos parâmetros em avaliação. Foi utilizada a endo celulase (EC 3.2.1.4) comercial de tipo 1,4-(1,3:1,4)-β-D-glucano 4-glucano-hidrolase produzida pelo fungo Tricoderma virido. Metodologicamente, este estudo foi efectuado em três etapas: a primeira correspondeu à caracterização global da matéria-prima; na segunda etapa submeteu-se a amostra a duas sequências de pré-tratamento de lavagens ácida (com ácido sulfúrico e ácido clorídrico), para avaliar o efeito nas propriedades químicas das lamas primárias; a terceira etapa foi caracterizada por sequências combinadas de pressão e tempo de pressurização da amostra que demonstrou melhores resultados na etapa anterior, portanto, dois ensaios a 400 MPa e um outro a 500 MPa, durante 15 minutos (na íntegra e outro por ciclos de 5) e 10 minutos, respectivamente. A amostra referente à lavagem com ácido clorídrico demonstrou os melhores resultados na caracterização química, sendo utilizada nos ensaios posteriores como a amostra referência de lamas primárias. A partir desta última etapa, inferiu-se acerca do efeito hiperbárico sobre a hidrólise enzimática, através da quantificação de açúcares redutores formados. Constatou-se que em todos os ensaios realizados, este efeito foi significativo e de elevada contribuição, traduzindo-se também num impacto positivo na velocidade e extensão da hidrólise. A sequência realizada a 400 MPa durante 15 minutos revelou os resultados mais promissores, registando-se uma melhoria na ordem de 43% no acréscimo da quantidade de açúcares redutores e um aumento na velocidade inicial de reacção em 25%, comparativamente ao estudo de amostras sem pressurização prévia.
During the active search for the profitability of solid waste from the production stages of pulp and paper, there is the prospect for energy recovery from the cellulosic fraction of primary sludge, in order to produce second generation biofuels. Indeed, this work intended to study the performance of the enzymatic hydrolysis in the primary sludge and, applying a high pressure pre-treatment, ascertain its real influence through the assessment of determined parameters. It was used a commercial endo cellulase enzyme (EC 3.2.1.4) of type 1,4-(1,3:1,4)-β-D-glucan 4-glucan hydrolase produced by the fungus Tricoderma virido. Attending to its methodology, this study was carried out through three major stages: the first one attended to an overall characterization of raw material; at a second stage, primary sludge was submitted throughout a two sequences of an acid pre- treatment wash (with sulphuric acid and chloridric acid), in order to assess its effect on chemical properties of primary sludge; the third and last stage was characterized by a combined sequences of pressure and pressurization time, that were applied to the sample which revealed the finest results during the previous stage. Those combined sequences involved two treatments at 400 MPa, during 15 minutes (one of them at cycles of 5 minutes each) and another treatment at 500 MPa, during 10 minutes. The sample submitted to acid chloridric wash showed better outcomes, referring to chemical characterization, so that it was distinguish as a reference sample of primary sludge, performing the subsequent study. The influence of high pressure treatment over enzymatic hydrolysis was evaluated by the amount of reducing sugars formed. It was able to verify in every trial that the quoted influence was decidedly effective, increasing the amount of reducing sugars formed and promoting an affirmative impact on reaction velocity as well as in its extension. The stage of treatment at 400 MPa during 15 minutes was considered as the preeminent one, regarding its results with an improvement of 43% related to the amount of reducing sugars formed, as well as an improvement of 25% of its initial velocity of reaction, in opposition to the sample without high pressure pre-treatment.

Mestrado em Gestão Ambiental, Materiais e Valorização de Resíduos
O presente trabalho teve como objectivo principal o estudo da incorporação de lamas resultantes do corte de granito ornamental em pastas cerâmicas conducentes à produção de cerâmicos de pavimento de grés porcelânico extrudido e de produtos cerâmicos estruturais, mais concretamente, de telhas. As propriedades finais das amostras sinterizadas incorporando este resíduo deveriam ser comparáveis ou mesmo superiores aos materiais cerâmicos equivalentes, já existentes no mercado. Para o efeito, foi efectuada uma caracterização física e química das matériasprimas e dos resíduos a utilizar nas diferentes formulações testadas, nomeadamente, distribuição de tamanhos de partícula, densidade, fases cristalinas presentes (DRX), propriedades térmicas e perda ao rubro. Posteriormente foi avaliado o efeito de cada componente nas propriedades das pastas, através do estudo de diferentes formulações com várias quantidades das matérias-primas seleccionadas. Estes estudos incluíram caracterizações das propriedades térmicas (ATD, ATG, dilatométrica) e plásticas. Finalmente, as pastas seleccionadas foram extrudidas, e os provetes foram caracterizados após sinterização através de medidas de densidade, índice piroplástico, absorção de água, da determinação da resistência mecânicas à flexão, e da análise microstrutural por Microscopia Electrónica de Varrimento (MEV). Do trabalho efectuado concluiu-se que a incorporação de lamas de granito, até 50%, pode resultar em produtos de grés porcelânico com propriedades superiores, em termos de absorção de água (≤0.25%) e resistência mecânica (>55 MPa), comparativamente a uma pasta industrial padrão de grés porcelânico. Os produtos obtidos obedecem aos requisitos das normas padrão ISO 13006, grupo BIa, para grés porcelânico. Por outro lado, este estudo demonstrou também que é possível produzir telhas, incorporando 10% de resíduo, com excelentes propriedades, nomeadamente, absorção de água inferior a 6%, menor deformação durante a sinterização e resistência mecânica em seco e cozido de aproximadamente 14 MPa e 38 MPa, respectivamente. Os resultados obtidos mostraram a viabilidade da reciclagem deste resíduo derivado do processo de transformação da pedra ornamental granítica em pastas cerâmicas tradicionais, permitindo classificá-lo como um subproduto em substituição de matérias-primas. Isto permite minimizar o impacto negativo no meio ambiente derivado da sua deposição contribuindo, simultaneamente, para preservar recursos naturais não renováveis. ABSTRACT: The present work aimed at studying the incorporation of wastes from natural rocks cutting and polishing industries, in order to produce extruded porcelain tile products and structural ceramics, namely roofing tiles. The sintered samples incorporating the sludge should have similar or even enhanced properties in comparison to the same kinds of industrial ceramic products already available in the market. Firstly, raw materials, including the sludge, were characterised by particle size distribution, density, X-Ray Diffraction (XRD), thermal properties and loss on ignition. In order to evaluate the effect of each component in the properties of the pastes, different formulations were prepared. The roles played by the different components and their effects on plasticity of pastes and on drying and firing processes were evaluated. Finally, the most promising formulations were selected for producing testing cylindrical rods samples by extrusion that were sintered and characterised by measuring the density, water absorption, flexural bending strength, and by microstructural observations by Scanning Electron Microscopy (SEM). The experimental results and their theoretical interpretation enable to conclude that the granite wastes in amounts up to 50% could be incorporated in porcelain tiles compositions conferring to the products superior properties in terms of water absorption (≤0.25%) and bending strength (>55 MPa), when compared to an industrial porcelain tile composition used as a benchmark. The new products fulfil the requirements of the ISO 13006 standard, group BIa (porcelain tiles). On the other hand, it was also concluded that it was possible to produce roofing tiles incorporating 10 % of waste having excellent properties, such as water absorption less than 6%, smaller pyroplastic deformation index and with green and sintering bending strength values of about 14 MPa and 38 MPa, respectively. The viability of recycling wastes derived from the granite cutting industry in ceramic pastes allows to simultaneously classifying this residue as a byproduct intended for being incorporated as a raw material in traditional ceramic industries. This also allows minimising the negative environmental impact due to its disposal and preserving non-renewable natural resources.

Dissertação apresentada na Faculdade de Ciências e Tecnologia da Universidade Nova de Lisboa para obtenção do grau de Mestre em Engenharia Sanitária
Uma das grandes preocupações a nível mundial prende-se sobretudo com a preservação do meio ambiente. Em particular, no caso das águas residuais geradas em grandes áreas urbanas e industriais, cujo impacto ambiental é muito significativo, tornou-se necessário impor limites de descarga mais restritivos o que tem levado a investir um grande esforço na melhoria e desenvolvimento dos processos de tratamento. A construção de novas instalações de tratamento e a reabilitação e, ou beneficiação de infraestruturas existentes, com vista à melhoria do seu desempenho hidráulico e sanitário, requer, cada vez mais, um estudo económico pormenorizado e cuidado de todas as etapas de tratamento disponíveis. Neste sentido, para cada tipo de efluente deve preconizar-se a solução óptima que leva a um desempenho mais eficiente e menos dispendioso, recorrendo a modelos matemáticos que descrevam a evolução das características físicas, químicas e biológicas da água residual a tratar. Nos últimos anos, a modelação matemática de processos de tratamento de águas residuais tornou-se uma ferramenta mundialmente aceite na prática de engenharia e amplamente utilizada por empresas de consultoria e entidades reguladoras. A crescente consciência e preocupação ambiental, observada sobretudo, nas duas últimas décadas,conduziram uma melhoria significativa da tecnologia de tratamento de águas residuais no campo da modelação matemática. O aumento de conhecimentos sobre os mecanismos de degradação biológica dos processos de tratamento por lamas activadas, resultou na publicação de uma série de modelos matemáticos actualmente utilizados como instrumentos de planeamento, projecto, análise e operação de infra-estruturas de tratamento. A presente dissertação pretende demonstrar que a modelação é uma parte essencial no dimensionamento de uma ETAR, evidenciando que os modelos matemáticos podem e devem ser utilizados para antever a resposta dinâmica dos sistemas biológicos a perturbações diversas,permitindo, na fase de projecto, a implementação de estratégias que garantam, na fase de exploração, um maior e melhor desempenho dos processos biológicos.

Mestrado em Engenharia do Ambiente
A crescente utilização de carvões activados nas mais diversificadas indústrias tem potenciado a procura de novas matérias-primas para a sua produção. Entre essas matérias encontram-se as lamas biológicas provenientes de estações de tratamento de águas residuais de indústria do papel. Todavia, são pouco conhecidas as características dos carvões com essa proveniência, pelo qual se procurou, com o presente estudo, dar um contributo para o seu desenvolvimento. Assim, e numa perspectiva comparada, a partir de diferentes matérias de origem, nomeadamente as referidas lamas mas também de carvão vegetal, prepararam-se várias amostras de carvão activado, usando diferentes variáveis durante o processo. As variáveis em estudo foram a granulometria do material de origem (1,0-4,0mm), o tempo de activação, (0,25h, 1h, 2h, 4h), a temperatura de activação (700ºC, 750ºC 850ºC 900ºC e 950ºC) e o agente de activação (H2O e CO2). Tendo em vista a caracterização dos carvões, foram analisadas a composição elementar e a composição das cinzas em várias fases do processo de preparação dos carvões, a área BET, a capacidade adsortiva dos carvões em relação ao n-hexano (modelos de isotérmicas de Langmuir e Freundlinch) e ainda a cinética de adsorção dos vários carvões em relação ao n-hexano. O estudo comparativo das propriedades dos carvões activados preparados permitiu concluir que a preparação de carvão activado produzido a partir de lamas biológicas provenientes de estações de tratamento de águas residuais é uma alternativa viável em aplicações menos exigentes, o melhor agente de activação é o vapor de água para a quase totalidade dos casos, tempos de activação de 4 horas e temperaturas mais elevadas possibilitam a preparação de carvões activados de maior capacidade adsortiva. O equipamento desenvolvido para a análise da capacidade adsortiva de n-hexano mostrou resultados coerentes com as análises de área BET. A utilização do n-hexano como adsorvato permitiu concluir que o modelo de isotérmica de Freundlich era adequado para representar o equilíbrio gás-sólido e que o modelo cinético de primeira ordem era apropriado para representar a velocidade de adsorção dos vários carvões activados ABSTRACT: The increasing use of activated carbons, in many kinds of industries, has intensified the demand for new raw materials. Among these are the biological sludges from wastewater treatment of paper industry. This study aims to better the knowledge of the characteristics of activated carbons produced from such raw materials. Several samples of activated carbon were prepared, from different raw materials, namely biological sewage sludge from two different wastewater industrial plants, using different variables during the trial. On the comparative analysis, additional samples were prepared for a vegetable charcoal and a commercial activated carbon. The variables in study were: particle diameter; (1,0 – 4,0 mm) activation time, (0,25, 1h, 2, 4h), activation temperature, (700ºC, 750ºC, 850ºC, 900ºC e 950ºC), and the activation agent (H2O and CO2). In order to characterize the activation carbon samples, the elementary composition and the composition of the ash in several phases of the preparation process, the BET area and the adsorptive capacity for n-hexane were analyzed. The adaptability of Langmuir and Freundlich isotherms models and a first order model for the adsorption were performed. The comparative study of the prepared activated carbons characteristics led to conclude that the production of activated carbon from sewage sludge is a viable alternative in less demanding applications. In the majority of the cases the best activation agent was the steam; 4 hours time activation and more elevated temperatures are the best options to make better quality activated carbon. The equipment developed to analyse the adsorptive capacity of nhexane showed coherent results with the BET area analysis. The model of Freundlich isotherm showed to be adequate. Good correlation coefficients were obtained, for the first order kinetic model.

Mestrado em Biotecnologia
O presente trabalho tem como objetivo a otimização do funcionamento de uma ETAR industrial, para tratamento de águas residuais resultantes da produção de biodiesel. A ETAR industrial em estudo engloba dois processos de tratamento: tratamento físico-químico através da utilização de uma unidade DAF e, tratamento biológico aeróbio por lamas ativadas. Ao longo deste estudo vários parâmetros físico-químicos foram analisados em particular sólidos totais, sólidos suspensos voláteis, carência química de oxigénio, teor em azoto amoniacal e fósforo total para além do pH e temperatura. Conseguiu-se optimizar a metodologia de análise dos sólidos totais reduzindo o tempo total da análise. Implementou-se a técnica de monitorização microbiológica das lamas activadas tendo-se identificado e quantificado alguns grupos de microrganismos característicos dos processos de lamas ativadas: ciliados nadadores, ciliados sésseis, ciliados móveis de fundo, amebas com teca, pequenos flagelados, ciliados carnívoros, Opercularia sp. e pequenos metazoários. Após a recolha destes dados físico-químicos e biológicos, diários e/ou periódicos, fez-se a avaliação do desempenho da ETAR. Foram identificadas as variáveis de controlo físico-químico que apresentavam maior variabilidade, nomeadamente o rácio alimentação/microrganismo (F/M) e o tempo de retenção de sólidos (SRT). Verificou-se que a instabilidade do F/M tem origem no facto da ETAR ter sido projetada para tratamento de um maior caudal de efluente ou de um efluente mais poluído. No caso do SRT a causa é o ineficiente sistema de purga de lamas. Concluiu-se que determinados parâmetros operacionais devem ser alterados por forma a otimizar-se o processo: o volume útil dos bioreactores deve ser reduzido de 110 m3 para 80 m3, a concentração de sólidos suspensos presente nos bioreactores deve reduzir-se em 20% e a purga de lamas deve ser cerca de 2 m3 por dia controlada de modo a poder manter a concentração de biomassa constante nos reatores. Relacionou-se ainda o efeito da alteração dos parâmetros físico-químicos na estrutura da comunidade da microfauna, através do teste de correlação não paramétrico de Spearman’rho. Esta análise estatística multivariada permitiu a identificação de bioindicadores do desempenho do sistema de lamas ativadas, e a criação de grupos de controlo positivo e negativo que tornam possível avaliar rapidamente o desempenho da ETAR através da monitorização das suas lamas.Com este estudo a empresa ficou dotada de mecanismos rápidos de avaliação do desempenho da ETAR de modo a que o seu funcionamento possa ser muito mais controlado.
The main goal of the present work is the optimization of the operation of an industrial wastewater treatment plant to treat biodiesel wastewater. The industrial WWTP in study comprises two treatment processes: physicochemical treatment through the use of a DAF unit and, biological treatment by activated sludge. During the study several physicochemical parameters were analyzed, namely total solids, volatile suspended solids, chemical oxygen demand, ammoniacal nitrogen and phosphorus content, besides pH and temperature. The methodology of total solids determination was optimized, reducing the analysis time. Microbiologic motorization of the activated sludge was implemented, with the identification and quantification of groups of microorganisms characteristics of the activated sludge process: free-swimming ciliates, sessile ciliates, crawling ciliates, testate amoebae, small flagellates, carnivorous ciliates, Opercularia sp. and small metazoan. After collecting these physicochemical and biological data, daily or periodically, the performance of the plant was evaluated. Therefore the physicochemical control variables that presents greatest variation were identified, namely food to microorganism ratio (F/M) and solids retention time (SRT). It was verified that the F/M instability is originated by the fact that the WWTP was designed to treat a larger amount of effluent or a more polluted one. On the other hand, SRT variability is caused by the inefficient sludge removal system. It was concluded that certain operational parameters should be changed in order to optimize the process: the useful volume of each bioreactor must be reduce from 110 m3 to 80 m3, the amount of suspended solids present in the bioreactors must be reduced in 20% and the amount of sludge purged from the system must be around 2 m3 per day, in order to maintain the biomass concentration constant in the reactors. It was also investigated the effect of the modification of the physicochemical parameters on the microfauna community, through the nonparametric correlation test of Spearman’rho. This multivariate statistical analysis allowed the identification of biological biomarkers of the activated sludge system performance, and the establishment of groups of positive and negative control, that make possible to quickly evaluate the performance of the WWTP by monitoring their sludge. With this study the company was provided with methodologies of rapid assessment of the performance of the WWTP so that its operation may be much more controlled.

No tratamento de águas residuais por lamas activadas, existem diferentes populações de protozoários e metazoários que se podem desenvolver durante o processo. A sua presença é fundamental para o bom desempenho da ETAR. Além de reduzirem a turvação do efluente final, estimulam o crescimento bacteriano, promovem a floculação e algumas espécies reduzem a poluição. É possível estabelecer uma estreita relação entre a predominância de determinadas espécies ou grupos de espécies, com parâmetros operacionais da ETAR, tais como os índices bióticos. Este procedimento requer a identificação e enumeração das diferentes espécies. No entanto, existem outros métodos, que apresentam relações entre a abundância de uma dada espécie ou grupo e os parâmetros da estação. O presente trabalho tem como objectivos: avaliar o funcionamento do sistema de tratamento de lamas activadas através da observação microscópica de protozoários e metazoários, identificação e contagem das espécies relevantes; estabelecer relações entre os organismos que contribuem para o processo de depuração de águas residuais e as condições de operação, como parâmetros físicoquímicos ou o desempenho da ETAR; e produzir uma ferramenta de apoio à gestão da ETAR, baseada em princípios biológicos. Pretende-se, ainda, contribuir e incentivar para a adopção de metodologias semelhantes em outros sistemas de lamas activadas em funcionamento no nosso País. Em termos metodológicos, a colheita de amostras foi realizada semanalmente na ETAR da ZIA durante dois meses e meio. Os parâmetros operacionais e físico-químicos foram obtidos junto da ETAR. A análise biológica foi efectuada por microscopia óptica. Avaliou-se qualitativa e quantitativamente a microfauna presente no tanque de arejamento, no poço de mistura de lamas e no clarificado de ambos os decantadores, a fim de se verificar as possíveis correlações desses parâmetros com a eficiência do sistema. Aplicou-se os resultados biológicos obtidos, em quatro modelos propostos para a avaliação do processo de tratamento, baseada em análises biológicas. Em termos qualitativos e na maior parte das observações, a lama apresentou boa qualidade. A ETAR da ZIA foi colonizada por tecamebas, principalmente Arcella sp. e Euglypha alveolata, em todo, o estudo e em todos os pontos analisados. No tanque de arejamento foram sempre observados ciliados nadadores livres. A densidade total de organismos no tanque de arejamento variou de 2982 e 7330 organismos/mL, com valor médio de 5995 organismos/mL. Relativamente, aos parâmetros estudados, os objectivos de remoção para o CBO5, CQO, SST e SSV foram alcançados.

Mestrado em Gestão Ambiental, Materiais e Valorização de Resíduos
A geopolimerização surge como uma via para processar e valorizar resíduos industriais alumino-silicatados, originando produtos com elevada resistência mecânica, estabilidade química e com a capacidade de confinar outros resíduos, incluindo os perigosos. Diversos resíduos industriais como por exemplo lamas (geradas pelos processos de filtração/clarificação da água potável, e do corte e polimento de granito), areia de fundição e rejeitados do processo de fabrico de aglomerados de argila expandida, foram caracterizados, com o objectivo de os utilizar e adaptar para a produção de geopolímeros, através da activação alcalina. Desta análise concluiu-se ser conveniente usar as lamas de filtração de água e os rejeitados de argila expandida como componentes ligantes ou activos da matriz geopolimérica a formar, atendendo o grau de finura e capacidade reactiva, enquanto que as lamas de corte de granito e a areia de fundição foram encaradas como inertes ou agregados, fino e grosseiro, respectivamente. As condições de processamento foram optimizadas, em termos de composição relativa dos constituintes, teor relativo e composição do activador (NaOH + Na2SiO3) e condições de cura, e os geopolímeros obtidos foram caracterizados, em termos de composição, microestrutura e propriedades físico-mecânicas relevantes. Em condições optimizadas obtiveram-se resistências à compressão superiores a 15MPa (17,9 MPa), o que perspectiva a utilização destes materiais em funções não estruturais. Em simultâneo, a baixa densidade relativa das amostras é compatível com isolamento térmico e acústico superior ao de betões convencionais, a confirmar em estudos futuros. De grande interesse foi o desempenho obtido quando o produto foi submetido a testes de lixiviação, para análise da capacidade de retenção de substâncias perigosas. Neste estudo, foi testada a retenção de crómio, sendo confirmada a elevada capacidade de fixação pela matriz geopolimérica. ABSTRACT: Geopolymerization appears as a viable way to process and add value to aluminum-silicate industrial wastes, originating products with high mechanical strength, high chemical inertia and enabling to encapsulate other waste materials, including dangerous ones. Several industrial wastes such as sludges (generated in potable water filtration/cleaning operations and in the cutting/polishing process of natural granite), foundry sand and powdered rejects from clay-based lightweight aggregates fabrication were characterized, in order to use or adapt them for the production of geopolymers through the alkaline activation process. From this analysis, it was decided to use the water filtration sludge and rejects of lightweight aggregates as binder or binders or activated components, based on their own reactivity and suitable fineness. By contrast, foundry sand and granite cutting sludge was found to be inert and then used as aggregates in the geopolymeric matrixes. Processing conditions were optimized, by playing with solids composition, concentration, nature and relative amount of activator (NaOH + Na2SiO3), and curing conditions. Cured samples were then fully characterized (composition, microstructure and relevant physical and mechanical properties). Optimal geopolymers show compressive strengths above 15MPa (maximum 17.9 MPa), an interesting value to perspective their use in non-structural applications. At the same time, density of the samples is lower then common concrete (based on Portlant cement), encouraging their use in thermally or acoustically insulating artefacts. Besides this, interesting performance was achieved when the product was submitted to leaching tests in order to test its encapsulation/fixation capabilities of hazardous substances. In this study, chromium was firmly fixed/immobilized in geopolymer matrix.

Mestrado em Engenharia Química
O funcionamento da ETARI da Bresfor é, atualmente, uma das maiores preocu-pações da empresa, já que o seu incorreto funcionamento se traduz em desper-dício e despesas acrescidas. O presente relatório de estágio teve como principal foco o estudo e proposta de melhoria do funcionamento desta ETARI. O estágio teve a duração de 4 meses e ocorreu no período de setembro de 2015 a janeiro de 2016. Durante este período, fez-se um estudo pormenorizado da ETARI e do seu funcionamento atual. Foi analisado o modelo de tratamento im-plementado, “Modified Ludzack-Ettinger”, bem como os efluentes tratados. Foi também realizado um estudo da atual instrumentação da ETARI e dos parâme-tros de controlo a serem considerados. Por último, com base em toda a informa-ção obtida, foi elaborada uma proposta de automatização da ETARI. Para além das tarefas que visavam atingir o objetivo do trabalho de estágio, , foram ainda desenvolvidos trabalhos adicionais, que se traduziram em benefici-ações ao funcionamento da ETARI e dos impactes ambientais do processo de produção nomeadamente, foi realizado um estudo do ciclo de água da empresa e apresentada uma proposta de otimização do mesmo. A redução do consumo e desperdício de água na empresa significará uma redução da carga de efluente a ser tratado. Finalmente, foi também feito um levantamento/identificação das fugas difusas de formaldeído baseado no protocolo EPA 21 “Determination of Volatile Organic Compound Leaks”. Este foi um estudo inovador na Bresfor, de grande importân-cia, não só ao nível ambiental mas também ao económico. Este permitirá facilitar a manutenção dos equipamentos, reduzir as emissões atmosféricas de formal-deído e também reduzir o desperdício de produto, minimizando assim a conta-minação do efluente a ser tratado na ETARI.
The actual functioning model of Bresfor’s wastewater treatment plant (WWTP) is one of the biggest concerns of the company, since its malfunctioning leads to waste and added expenses for the company. This internship report had as main focus the analysis and proposal to improve the performance of the WWTP. This internship had the duration of 4 months and occurred in the period from September 2015 until January 2016. During this period, a detailed analysis of the WWTP was conducted. The implemented treatment model was studied, Modified Ludzack-Ettinger, as well as the effluents to be treated. The instrumentation and control parameters were also studied. Finally, based on all the obtained infor-mation, an automatization model was proposed. Furthermore, two additional studies were conducted, that reveled to be beneficial to the WWTP functioning. The company’s water usage mapping was studied and an optimization plan was proposed. The reduction of water consume will lead to a decrease in effluent to be treated. Finally, the identification and quantification of diffuse emissions was conducted, based on EPA 21 protocol “Determination of Volatile Organic Compound Leaks”. This was an innovative study in Bresfor, of great importance, not only at the en-vironmental level but also for the company. It will ease the maintenance of equip-ment, allow the decrease of atmospheric emissions of volatile organic com-pounds (formaldehyde) and also decrease the product waste while minimizing the contamination of the effluent to be treated by the WWTP.

Mestrado em Engenharia de Materiais
O destino final dos resíduos gerados no fabrico da pasta de papel em Portugal é uma das preocupações crescentes deste setor, já que as normativas europeias são cada vez mais restritas no que respeita à sua deposição em aterro. Impulsionados por este facto o grupo Portucel/Soporcel (gPS) procura soluções mais sustentáveis, como a valorização dos resíduos gerados no seu processo de fabrico em outros setores industriais. O fabrico da pasta de papel pelo método Kraft utilizado pelo gPS, origina diversos resíduos como as lamas geradas na recuperação de químicos e no tratamento de efluentes, assim como as cinzas volantes resultantes da cogeração de energia. O presente trabalho pretende encontrar uma aplicaçãomais sustentável dos resíduos descritos anteriormente. Nomeadamente a sua utilização como matérias-primas secundárias no fabrico de clínquer/cimento e posterior aplicação em argamassas. Na primeira etapa do trabalho realizou-se a caracterização detalhada dos resíduos, em colaboração com o laboratório Raiz (pertencente ao gPS), e efetuou-se o levantamento das quantidades geradas. Com base nestas análises e de acordo com os produtos-alvo para reciclagem, foram previstos estudos de tratamento e adaptação dos componentes ou das misturas, que garantam melhores condições de transporte e incorporação. Em seguida foram elaboradas diferentes misturas em cru e foram testados distintos ciclos de tratamento térmico por forma a obter diferentes tipos de clínquer (belítico e Portland). Posteriormente formularam-se argamassas e testou-se sua adequabilidade como argamassas de reboco. A partir dos resíduos em estudo obteve-se clínquer belítico e clínquer Portland completamente ecológicos (obtidos a partir apenas de resíduos). No caso do clínquer Portland consegui-se uma redução da temperatura de processamento a qual acarreta benefícios processuais e económicos e resulta da presença de impurezas mineralizadoras em alguns dos resíduos. As argamassas produzidas neste trabalho têm potencial para ser utilizadas em rebocos exteriores ou interiores. Neste estudo também foram detetadas limitações, as quais perspetivam algumas dificuldades na transposição para o fabrico industrial de clínquer/cimento. Estas são a possibilidade de ocorrência de reações expansivas do tipo álcalis-agregados o que implica a adoção de correções composicionais para minimizar/evitar problemas de durabilidade e o facto de os resultados experimentais corresponderem só a um lote de resíduos, pelo que será necessário recolher periodicamente amostras nas instalações do gPs, efetuar a sua caracterização e, se necessário, prever medidas de loteamento e homogeneização das misturas.
The final destination of wastes generated in the production of paper pulp in Portugal is an important concern in this setor, since European regulations are becoming ever stricter regarding their landfill. Driven by this fact, the Portucel/Soporcel group (gPS) is looking for more sustainable solutions, such as the use of the generated wastes in the production processes of other industrial sectors. The production of paper pulp by the Kraft method used by the gPS generates various wastes, such as sludge from the recovery circuit of chemical reagents and from the wastewater treatment, as well as fly ash from the cogeneration of energy. This work tries to provide a more sustainable use for the wastes previously described, using them as secondary raw materials in the manufature of clinker/cement, and subsequent application in mortars. The first step involved the detailed characterization of the residues, in collaboration with the RAIZ laboratory (belonging to gPS), and a survey of the amounts generated. Based on these analyses, and in accordance with the target products for recycling, were provided treatment studies and adaptation of the components or mixtures, ensuring better transport and incorporation conditions. Then, different blends were prepared and tested with different heat treatment cycles, in order to obtain different types of clinker (belitic and Portland). Subsequently, mortars were formulated, and their suitability as plastering mortars was tested. From the wastes under study environmentally friendly belitic and Portland clinker were manufactured. In the case of Portland clinker, a reduction of the processing temperature was achieved, resulting from the presence of mineralizing impurities in some of the wastes, with procedural and economic benefits. The mortars produced in this work have potential for use in exterior or interior plasters. From this study, were also detected some limitations, which do provide some difficulties in the industrial scale up of the clinker production. These are the possibility of expansive reactions of alkali-aggregate type, which implies the adoption of compositional corrections to minimize/avoid durability problems, and the fact that the experimental results obtained correspond to a single lot of waste, so it will be necessary to periodically collect samples in the plants of the gPS, perform a full characterization and, if necessary, introduce measures of blending and homogenization.