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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Stridsyxor eller båtyxor : En diskussion om symboliken och dess betydelse

Bergstedt, Märta-Lena January 2012 (has links)
My intention with this paper is to try to understand the meaning of the double sex symbols which can be identified on a number of Neolithic so called battle axes from the region round the lake Mälaren in Sweden. My conclusions are drawn after having studied a number of archaeological thesises. I have realized that the society was egalitarian from what is said about the funeral habits since women and men were buried with the same care. Ceramics from the Skogsmossen site show a very long continuity over 15-20 generations. These facts indicate a peaceful society without traumatic breaks where knowledge would have been lost. The fingerprints produced on the ceramics are those of women, since they do not seem to fit with the hands of men. Women are by this fact persumed to be the producers of ceramics. In early and primitive farming digging sticks were used, often with a weight. My conclusion is that the boat axe can be a magic tool used on the digging sticks. We have to understand the boat axes as spiritual helpers to fruitful and fertile success.
2

"A tale of two weapons" Late Holocene hunting technology in North Central Texas /

Miller, Mickey Joe. Ferring, C. Reid, January 2009 (has links)
Thesis (M.S.)--University of North Texas, May, 2009. / Title from title page display. Includes bibliographical references.
3

Entangled worlds : archaeologies of ambivalence in the Viking age

Gardela, Leszek January 2012 (has links)
When all available sources on the Viking world are combined, there is a strong sense that the Scandinavians of the late Iron Age (8th-11th centuries AD) recognised no clear distinctions between the profane and the sacred. The latter could manifest itself in different ways, in places, beings or objects, and it often aroused ambivalent feelings of both fear and awe. This thesis explores these entanglements and the notion of ambivalence in relation to a particular group of Viking-Age individuals involved in the practice of magic (e.g. seiðr). Chapters 1-3 form the background for the considerations on ritual specialists' lives, tools of trade and ways of burial. After a detailed review of Viking-Age funerary practices, focus shifts towards the corpus of so-called ‘deviant burials', which in recent years have often been interpreted as belonging to ritual specialists. Chapter 4 compares the written and archaeological evidence for the funerary treatment of ritual specialists. Particular attention is devoted to graves where the deceased are covered with stones, since in the written sources execution by stoning is often employed as a punishment for malevolent magic. Nonetheless, caution is suggested in labeling all of them as belonging to ritual specialists and the necessity of a more individual, contextual approach is proposed. Chapter 5 examines a specific group of Viking-Age artefacts that usually take the form of iron rods, which have recently been interpreted as magic staffs. These items are discussed in the light of Old Norse texts and comparative materials from other areas of the world. Ultimately, the thesis embraces the notion of ambiguity in Viking attitudes to the supernatural, viewing this not as an obstructive problem but as an active component of interpretation. This combines an appropriate caution in approaching a difficult aspect of past societies, with a sensible refusal to introduce more rigid definitions than those used by the Vikings themselves.
4

Balance factors associated with telescoping walking poles use by older people

Horn, Bryon G. January 2003 (has links)
The purpose of this study was to determine the extent to which a novel assistive device improved two dimensional base of support (BOS) as compared to unassisted walking. Telescoping walking poles (T poles) are designed to allow a gait pattern more closely resembling unassisted gait and provide enhanced stability. Nine healthy male and female subjects who had no recent lower extremity pathology or surgery and were between the ages of 59 and 78 were recruited from the community to participate. Subjects were instructed to use the T poles in a consistent manner and were monitored through weekly supervised training sessions. At the conclusion of the study, motion analysis was performed using video collected from six cameras. Subjects were adorned with reflective markers on the toe and heel of their shoes as well as the tips of the T poles. These markers were used to define the BOS. Two dimensional analyses revealed a significant increase in base of support, an average of 316% over the entire gait cycle as well as 531% at heel strike and 126 % at toe off with the T poles. These results support the T poles as an effective intervention in enhancing stability in an elderly population of recreational walkers. / School of Physical Education
5

The Effect of Novel Frying Methods on Quality of Breaded Fried Foods

Bengtson, Rhonda J. 31 October 2006 (has links)
Fried foods are popular around the world. They are also high in fat and considered unhealthy by many people. Reducing the fat content of fried food may allow for even more growth in their popularity, while allowing for healthier eating. Furthermore, vacuum-frying and frying with nitrogen gas have both been shown to extend the life of frying oil. In this study, the use of novel frying methods as a way to reduce fat content of breaded fried foods was evaluated. A pressure fryer was modified so that fish sticks could be vacuum-fried and fried using external gas (nitrogen and compressed air) as the pressurizing media. These products were compared to those pressure fried and fried atmospherically in terms of crust color, moisture content, oil content, texture, and juiciness. Overall, products fried using nitrogen and air were not found to be significantly different (p < 0.05) from each other. These products were both more tender and lower in oil content than steam-fried fish sticks. The energy to peak load of fish sticks fried with air was 123.10 J/kg, fish sticks fried with nitrogen had an energy to peak load of 134.64 J/kg, and fish sticks fried with traditional pressure frying had a peak load of 158.97 J/kg. The crust oil contents of fish sticks fried with air, nitrogen, and steam were 17.35%, 15.88%, and 23.31% oil by weight, respectively. In other words, using nitrogen or air to fry fish sticks reduced the fat uptake in the crust by 31.8% and 25.6% compared to traditional pressure frying, respectively. The only area where vacuum-frying had a significant effect, when compared to pressure-fried and atmospherically-fried fish sticks, was in juiciness. Vacuum-frying created significantly juicier fish sticks than the other two frying methods. Vacuum-fried fish sticks had juiciness of 43.03% (120oC) and 41.31% (150oC), while pressure-fried fish sticks had juiciness of 30.01% (175oC) and 32.93% (190oC), and atmospherically-fried fish sticks had juiciness of 31.56% (175oC) and 29.38% (190oC). In addition, vacuum-fried fish sticks were more tender than atmospherically-fried fish sticks. The results of this study demonstrated that frying with external pressurizing media can be used to reduce oil content in fish sticks, while also creating products that are more tender than conventionally pressure-fried fish sticks. In addition, vacuum-frying, which has been shown to extend oil life compared to pressure frying because of the lower temperatures involved, can be used to create fish sticks that are comparable to pressure-fried fish sticks, but juicier. / Master of Science
6

Development of finish cooking methods for producing low-fat breaded cheese sticks

Yavuz, Nihat 18 January 2011 (has links)
Deep-fat fried foods have unique characteristics that attract consumers but their high fat contents must be reduced in order to provide healthy foods along with high quality. In the first part of this study, effects of frying temperature and frying pressure on the quality of partially fried breaded cheese sticks were determined. In the second part, far infrared finish cooking methods were compared to traditional deep-fat frying in terms of product quality. Increasing frying temperature significantly (P<0.05) reduced fat and moisture contents of the samples and increased crispness and exterior hardness. Pressure did not affect crust fat content of the samples significantly (P>0.05). However, increasing frying pressure resulted in the samples having higher moisture contents. Crispness and exterior hardness of pressure-fried cheese sticks were lower than traditional deep-fat fried samples. Increasing frying temperature and pressure resulted in darker sample color. Par-fried far-infrared finish cooked cheese sticks had lower fat contents than deep-fat fried cheese sticks had. Moisture contents of far-infrared finish-cooked samples were higher than those of deep-fat fried samples. Far-infrared finish cooking significantly (P<0.05) reduced crispness and exterior hardness of breaded cheese sticks. / Master of Science
7

Čichové testy v diagnostice Alzheimerovy nemoci a jejich kognitivní koreláty / Smell tests in Alzheimer's disease diagnostics and their cognitive correlates

Vaškovicová, Michaela January 2020 (has links)
This thesis is focused on the use of olfactory tests in neuropsychological diagnostics of Alzheimer's disease and on the cognitive correlates of these tests. The literature review briefly summarizes current knowledge of the diagnostics of Alzheimer's disease and its dynamically developing criteria. Attention is also paid to the olfactory impairment that occurs during the course of this disease, as well as to specific psychophysical olfactory tests. The research part summarizes the results of research within the grant GACR 17-05292S, 01. 01. 2017 - 31. 12. 2019 - New blood biomarkers for early diagnosis, prognosis and course of Alzheimer's disease held at the Psychiatric Clinic of the First Faculty of Medicine and General Teaching Hospital. The exploratory analysis examines possible cognitive correlates of the olfactory Sniffin' Sticks test. Practical experience with olfactory test is evaluated in the discussion. Keywords Alzheimer's disease, olfactory deficit, smell tests, Sniffin'-Sticks, neuropsychological diagnostics
8

Adaption des 'Sniffin' Sticks' Riechidentifikationstests für Ägypten

Taut, Maria 19 October 2018 (has links)
Riechen ist ein unterschätzter Sinn, der in unserem alltäglichen Leben zum Bespiel bei Nahrungsaufnahme, Partnerwahl und Erkennung von Gefahren eine große Rolle spielt. Für die Diagnostik von Riechstörungen ist ein kulturell angepasster, validierter Riechtest unablässig, da Menschen nicht überall mit den gleichen Gerüchen vertraut sind. Für den ägyptischen Kulturkreis gab es einen solchen Test bisher nicht. Der „Sniffin‘ Sticks“ Test ist ein in Europa häufig angewandter Riechtest. Er besteht aus einer Diskriminationstestung, einer Riechschwellentestung und einem Identifikationsteil. Letzterer ist der Teil, der mit Sicherheit einer kulturellen Adaptation bedarf. In dieser Studie wurde der deutsche „Sniffin‘ Sticks“-Identifikationstest so modifiziert, dass er für ägyptische Probanden angewendet werden kann. Wir konnten erste normierte Daten erheben. Die Probanden erzielten im angepassten „Sniffin‘ Sticks“-Identifikationstest weitestgehend ähnliche Ergebnisse wie die Teilnehmer anderer Nationalitäten. Jedoch konnte zwischen Gruppen mit nur bedingt unterschiedlichen Beeinträchtigungen (Normosmiker und Teilnehmer mit leichter Riechminderung, sowie Anosmiker und Teilnehmer mit schwerer Riechminderung) kein signifikanter Unterschied hinsichtlich der Testergebnisse gefunden werden. Dies führen wir darauf zurück, dass Probanden ihr Riechvermögen häufig selbst einschätzten, was nicht immer zu einer korrekten Zuordnung zu den einzelnen Testgruppen führte. Weiterhin konnten keine signifikanten geschlechtsspezifischen Unterschiede des Riechvermögens nachgewiesen werden. Wie in anderen Studien bereits beobachtet, schnitten jedoch auch die ägyptischen Frauen im Vergleich zu den Männern tendenziell besser ab. Eine Abnahme des Riechvermögens mit dem Alter ist vielfach dokumentiert und über kulturelle Grenzen hinweg einheitlich beobachtet worden. Auch die ältere ägyptische Bevölkerung bildet hier keine Ausnahme. Es fiel aber auch ein schlechteres Abschneiden der älteren Probanden im Vergleich zu anderen Nationalitäten gleichen Alters auf. Wir erklärten dies im Hinblick auf die Akkumulation schädlicher Umwelteinflüsse und die geringe Stichprobengröße. Letztendlich existiert nun ein validierter Test zur Testung des Riechvermögens ägyptischer Probanden. Sicherlich werden weitere Studien notwendig sein, um die bisher erhobenen Daten zu stärken.:Zusammenfassung 4 Summary 5 Inhaltsverzeichnis 6 Abkürzungsverzeichnis 8 1 Einleitung 9 2 Theorie 11 2.1 Der Geruchssinn – Grundlagen 11 2.1.1 Anatomie 11 2.1.2 Physiologie und Biochemie 14 2.2 Ätiologie und Pathologie der Riechstörungen 15 2.2.1 Sinunasal bedingte Riechstörungen 15 2.2.2 Traumatisch bedingte Riechstörungen 16 2.2.3 Nicht-sinunasal bedingte Riechstörungen 16 2.3 Diagnostik - Riechtestung 17 2.3.1 Einteilung der Diagnostik 18 2.3.1.1 Objektive Testverfahren 18 2.3.1.2 Psychophysische Testverfahren – Der „Sniffin‘ Sticks“-Test 19 2.3.2 „Sniffin‘ Sticks“-Identifikationstest – Kulturelle Adaption 21 2.4 Therapieansätze 22 2.5 Einfluss des Alters auf den Geruchssinn 23 2.6 Einfluss des Geschlechts auf den Geruchssinn 24 2.7 Einfluss des Rauchens auf den Geruchssinn 24 3 Ziele 24 4 Material und Methoden 25 4.1 Studiendesign und Studienablauf 25 4.2 Patientenauswahl 29 4.3 Aufklärung und Einverständnis 30 4.4 Die statistische Auswertung 30 5 Ergebnisse 30 5.1 Auswahl der Gerüche 30 5.2 Vergleich von subjektiv riechgesunden und riechgeminderten Personen 31 5.3 Einfluss des Geschlechts auf den Geruchssinn 33 5.4 Einfluss des Alters auf den Geruchssinn 33 5.5 Reliabilität und Korrelationsanalysen 34 6 Diskussion 34 6.1 Diskussion der Ergebnisse 34 6.1.1 Ergebnisse der Auswahl der Gerüche 35 6.1.2 Ergebnisse des Vergleichs von riechgesunden und riechgeminderten Probanden 36 6.1.3 Ergebnisse der geschlechtsspezifischen Untersuchung 36 6.1.4 Vergleich mit anderen normativen Daten 36 6.2 Diskussion der Methoden 37 6.2.1 Übersetzung und Arbeitssprache 37 6.2.2 Auswahl der Probanden 37 7 Literaturverzeichnis 40 8 Anhang 49 8.1 Abbildungsverzeichnis 49 8.2 Tabellenverzeichnis 49 Danksagung 50 Erklärungen 51 / Smelling is one of our most underestimated senses, although it plays a huge role in our daily life, when it comes to eating, socializing and recognizing dangers. For diagnosing smelling disorders, a good validated and cultural adapted test is very important. People all over the world aren’t used to the same sort of odors. That’s why cultural adaptation is so important. For Egyptians or the Arabic population there was no validated test like that so far. The „Sniffin‘ Sticks“ Test is such a tool for diagnosing smelling disorders. It consists of a discrimination part, a threshold testing part and an identification part. This last one is the one that needs to be surely adapted, if the test is supposed to be used for patients from a different cultural background. That was the purpose of this study: To adapt the German „Sniffin‘ Sticks“ Test for making it applicable in Egypt. We were able to collect first normative data, with mostly similar results to the ones of other cultural groups. Nevertheless there were some obstacles. We could not find significant differences between participants with slightly different intensity of smell loss. That might be due to the fact that participants mostly rated their ability of smell themselves, so we could match them to one of the study groups. As this is often not very accurate, it might explain why we could not discriminate well between people rating themselves as strongly impaired and anosmic for example. Also we could not find significant differences concerning the ability to smell in terms of sex. This is an often-observed situation, although the tendency for women to slightly outperform men is also documented. It is the same with Egyptian women. Another well-known fact is the decrease of the sense of smell with age. That is as well shown in our data. The only difference was, that old participants did not score as good as older people from other countries. One reason for that might be the small sample of older participants we had, another reason might be the high load of pollution people in Cairo are exposed to. Finally now there is first normative data and a validated smelling test for the Egyptian population. Further studies will be necessary to undermine the previous work and create an even stronger test.:Zusammenfassung 4 Summary 5 Inhaltsverzeichnis 6 Abkürzungsverzeichnis 8 1 Einleitung 9 2 Theorie 11 2.1 Der Geruchssinn – Grundlagen 11 2.1.1 Anatomie 11 2.1.2 Physiologie und Biochemie 14 2.2 Ätiologie und Pathologie der Riechstörungen 15 2.2.1 Sinunasal bedingte Riechstörungen 15 2.2.2 Traumatisch bedingte Riechstörungen 16 2.2.3 Nicht-sinunasal bedingte Riechstörungen 16 2.3 Diagnostik - Riechtestung 17 2.3.1 Einteilung der Diagnostik 18 2.3.1.1 Objektive Testverfahren 18 2.3.1.2 Psychophysische Testverfahren – Der „Sniffin‘ Sticks“-Test 19 2.3.2 „Sniffin‘ Sticks“-Identifikationstest – Kulturelle Adaption 21 2.4 Therapieansätze 22 2.5 Einfluss des Alters auf den Geruchssinn 23 2.6 Einfluss des Geschlechts auf den Geruchssinn 24 2.7 Einfluss des Rauchens auf den Geruchssinn 24 3 Ziele 24 4 Material und Methoden 25 4.1 Studiendesign und Studienablauf 25 4.2 Patientenauswahl 29 4.3 Aufklärung und Einverständnis 30 4.4 Die statistische Auswertung 30 5 Ergebnisse 30 5.1 Auswahl der Gerüche 30 5.2 Vergleich von subjektiv riechgesunden und riechgeminderten Personen 31 5.3 Einfluss des Geschlechts auf den Geruchssinn 33 5.4 Einfluss des Alters auf den Geruchssinn 33 5.5 Reliabilität und Korrelationsanalysen 34 6 Diskussion 34 6.1 Diskussion der Ergebnisse 34 6.1.1 Ergebnisse der Auswahl der Gerüche 35 6.1.2 Ergebnisse des Vergleichs von riechgesunden und riechgeminderten Probanden 36 6.1.3 Ergebnisse der geschlechtsspezifischen Untersuchung 36 6.1.4 Vergleich mit anderen normativen Daten 36 6.2 Diskussion der Methoden 37 6.2.1 Übersetzung und Arbeitssprache 37 6.2.2 Auswahl der Probanden 37 7 Literaturverzeichnis 40 8 Anhang 49 8.1 Abbildungsverzeichnis 49 8.2 Tabellenverzeichnis 49 Danksagung 50 Erklärungen 51
9

Mecanismos de toxicidade do conteúdo de sinalizadores luminosos (light-sticks) -- formação de adutos com DNA e dano oxidativo em células em cultura / Mechanisms of toxicity of the contents of beacons (light-sticks) DNA addcts formation and oxidative damage in cultured cells

Silva, Amanda Lucila Medeiros da 02 September 2010 (has links)
Bastões plásticos quimioluminescentes, chamados light sticks, são usados por companhias pesqueiras e descartados nas praias. Moradores locais utilizam seus conteúdos como repelentes, óleo bronzeador e medicamento para dores nas articulações. Nós investigamos a reatividade das soluções de bastões de light sticks coletados em praias brasileiras e a toxicidade celular de seus conteúdos e também de soluções de light stick de bastões novos. Produtos da reação dos conteúdos de light stick descartado com 2\'-desoxiguanosina (dGuo) foram analisados por HPLC/UV/ESI-MS/MS. Um aduto foi purificado e caracterizado em espectrômetro de massas por Dissociação Induzida por Colisão (CID) e através de experimentos de 1H RMN. A estrutura do aduto revelou que o produto de degradação de bis(triclorofenil)oxalato é reativo para nucleófilos in vitro. O mesmo aduto foi detectado em DNA de timo de bezerro incubado in vitro com a solução do light stick descartado pelo uso HPLC/ESI-MS/MS. Além do DNA, albumina também foi modificada pelos conteúdos de light stick descartado. Células HepG2 foram incubadas por 16 h com 0.0125% - 0.12% (v/v) das soluções de light sticks: (i) coletadas na praia, (ii) obtidas imediatamente após a reação quimioluminescente no laboratório, e (iii) previamente a reação, contendo ou n-butil-ftalato, difenilantraceno, e bis(triclorofenil)oxalato (solução 1), ou dimetil-ftalato, H2O2, e salicilato de sódio (solução 2). A sobrevivência celular foi avaliada pelo teste do XTT, corante cristal violeta e lactato desidrogenase realizados em placas de 96 poços. Com as concentrações testadas foram obtidas significativamente a morte celular. O dano oxidativo ao DNA celular foi avaliado pela análise da 8-oxo-2\'-desoxiguanosina através do equipamento HPLC/ESI-MS/MS, que revelou aumento de alterações nas células tratadas com 0.006% das soluções de light stick de bastões descartados e novos. Nossos dados apontam genotoxicidade e citotoxicidade das soluções de light sticks e podem contribuir como alerta a autoridades públicas para proibição do uso incontrolado. / Chemiluminescent plastic rods, called light sticks, are used by fishery companies and littered on the shores. Local inhabitants use their contents as repellents, tanning oil, and medicine for joint pain. We have investigated the reactivity of spent light stick solutions collected on brazilian beaches and the cellular toxicity of their contents as well as that of brand-new light stick solutions. Products of the reaction of the spent light stick contents with 2\'-deoxyguanosine (dGuo) were analyzed by HPLC/UV/ESI-MS/MS. A dGuo adduct was purified and characterized in a Collision Induced Dissociation (CID) mass spectrometer and through 1H NMR experiments. The adduct structure revealed that a degradation product of bis(trichlorophenyl)oxalate is reactive towards nucleophiles in vitro. The same adduct was detected in calf thymus DNA incubated in vitro with spent light stick solution, by using HPLC/ESI-MS/MS. Besides DNA, albumin was also modified by spent light stick contents. HepG2 cells were incubated for 16 h with 0.0125% 0.12% (v/v) of light stick solutions: (i) collected on the beaches, (ii) obtained immediately after the chemiluminescent reaction in the laboratory, and (iii) previously the reaction, containing either n-butyl-phthalate, diphenylanthracene, and bis(trichlorophenyl)oxalate (solution 1), or dimethyl-phthalate, H2O2, and sodium salicylate (solution 2). Cell survival was evaluated by the XTT, crystal violet dye, and lactate dehydrogenase assays performed in 96 well plates. The concentrations tested were found to significantly kill cells. Oxidative damage to cellular DNA was assessed by 8-oxo-2\'-deoxyguanosine analysis via an HPLC/ESI-MS/MS equipment, which revealed increased changes in cells treated with 0.006% of spent and brand-new light stick solutions. Our data point to important genotoxicity and cytotoxicity of the light stick solutions and may contribute to alert public policies to ban their uncontrolled use.
10

Mecanismos de toxicidade do conteúdo de sinalizadores luminosos (light-sticks) -- formação de adutos com DNA e dano oxidativo em células em cultura / Mechanisms of toxicity of the contents of beacons (light-sticks) DNA addcts formation and oxidative damage in cultured cells

Amanda Lucila Medeiros da Silva 02 September 2010 (has links)
Bastões plásticos quimioluminescentes, chamados light sticks, são usados por companhias pesqueiras e descartados nas praias. Moradores locais utilizam seus conteúdos como repelentes, óleo bronzeador e medicamento para dores nas articulações. Nós investigamos a reatividade das soluções de bastões de light sticks coletados em praias brasileiras e a toxicidade celular de seus conteúdos e também de soluções de light stick de bastões novos. Produtos da reação dos conteúdos de light stick descartado com 2\'-desoxiguanosina (dGuo) foram analisados por HPLC/UV/ESI-MS/MS. Um aduto foi purificado e caracterizado em espectrômetro de massas por Dissociação Induzida por Colisão (CID) e através de experimentos de 1H RMN. A estrutura do aduto revelou que o produto de degradação de bis(triclorofenil)oxalato é reativo para nucleófilos in vitro. O mesmo aduto foi detectado em DNA de timo de bezerro incubado in vitro com a solução do light stick descartado pelo uso HPLC/ESI-MS/MS. Além do DNA, albumina também foi modificada pelos conteúdos de light stick descartado. Células HepG2 foram incubadas por 16 h com 0.0125% - 0.12% (v/v) das soluções de light sticks: (i) coletadas na praia, (ii) obtidas imediatamente após a reação quimioluminescente no laboratório, e (iii) previamente a reação, contendo ou n-butil-ftalato, difenilantraceno, e bis(triclorofenil)oxalato (solução 1), ou dimetil-ftalato, H2O2, e salicilato de sódio (solução 2). A sobrevivência celular foi avaliada pelo teste do XTT, corante cristal violeta e lactato desidrogenase realizados em placas de 96 poços. Com as concentrações testadas foram obtidas significativamente a morte celular. O dano oxidativo ao DNA celular foi avaliado pela análise da 8-oxo-2\'-desoxiguanosina através do equipamento HPLC/ESI-MS/MS, que revelou aumento de alterações nas células tratadas com 0.006% das soluções de light stick de bastões descartados e novos. Nossos dados apontam genotoxicidade e citotoxicidade das soluções de light sticks e podem contribuir como alerta a autoridades públicas para proibição do uso incontrolado. / Chemiluminescent plastic rods, called light sticks, are used by fishery companies and littered on the shores. Local inhabitants use their contents as repellents, tanning oil, and medicine for joint pain. We have investigated the reactivity of spent light stick solutions collected on brazilian beaches and the cellular toxicity of their contents as well as that of brand-new light stick solutions. Products of the reaction of the spent light stick contents with 2\'-deoxyguanosine (dGuo) were analyzed by HPLC/UV/ESI-MS/MS. A dGuo adduct was purified and characterized in a Collision Induced Dissociation (CID) mass spectrometer and through 1H NMR experiments. The adduct structure revealed that a degradation product of bis(trichlorophenyl)oxalate is reactive towards nucleophiles in vitro. The same adduct was detected in calf thymus DNA incubated in vitro with spent light stick solution, by using HPLC/ESI-MS/MS. Besides DNA, albumin was also modified by spent light stick contents. HepG2 cells were incubated for 16 h with 0.0125% 0.12% (v/v) of light stick solutions: (i) collected on the beaches, (ii) obtained immediately after the chemiluminescent reaction in the laboratory, and (iii) previously the reaction, containing either n-butyl-phthalate, diphenylanthracene, and bis(trichlorophenyl)oxalate (solution 1), or dimethyl-phthalate, H2O2, and sodium salicylate (solution 2). Cell survival was evaluated by the XTT, crystal violet dye, and lactate dehydrogenase assays performed in 96 well plates. The concentrations tested were found to significantly kill cells. Oxidative damage to cellular DNA was assessed by 8-oxo-2\'-deoxyguanosine analysis via an HPLC/ESI-MS/MS equipment, which revealed increased changes in cells treated with 0.006% of spent and brand-new light stick solutions. Our data point to important genotoxicity and cytotoxicity of the light stick solutions and may contribute to alert public policies to ban their uncontrolled use.

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