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Os produtos para alisamento das fibras capilares são amplamente utilizados no Brasil principalmente, pelo público feminino. Porém, estes procedimentos podem causar danos ao cabelo do usuário e, também, para o profissional que está atuando. Os alisantes químicos podem ser divididos em dois grupos: alcalinos e ácidos. Os primeiros (tioglicolato de amônio e os hidróxidos de sódio ou guanidina) apresentam valor de pH elevado (superior a 9,0) e alisam por meio da quebra e reorganização das pontes de dissulfeto (S-S) presentes na queratina, proteína estrutural da fibra capilar. Os alisantes ácidos como o formaldeído, ácido glioxílico e seus associados, possuem pH baixo (≥ 2,0) e causam uma reorganização no interior da fibra e geralmente leva a formação de um filme na superfície do fio. O ácido glioxílico associado à carbocisteína e aminoácidos (nomenclatura INCI -International Nomenclature of Cosmetic Ingredient apresentada entre parênteses) (Glyoxyloyl Carbocysteine (and) Glyoxyloyl Keratin Aminoacids (and) Water) é o único ingrediente permitido ao uso como alisante ácido até o momento. O objetivo deste trabalho foi estudar o efeito deste alisante ácido incorporado em uma emulsão óleo e água (O/A) com valores de pH 1,0 e 2,0 (com reaplicações); e o impacto que podem causar nas propriedades mecânicas e químicas da fibra capilar, como força de ruptura, coloração, elasticidade e teor de triptofano da fibra capilar. E também o efeito da radiação ultravioleta nos fios alisados. Nos testes realizados observou-se que as mechas tratadas com a emulsão a pH 1,0 obtiveram melhor resultado de alinhamento das cutículas e capacidade alisante da fibra, com penteabilidade superior ao cabelo virgem (59,4 %), enquanto as mechas com a formulação pH 2,0 foi apenas 33,0%. Entretanto, a força de tração para a ruptura do fio foi inferior, diminuindo em 16,0% (pH 1,0) e 9,0 % (pH 2,0). Quanto a variação da coloração, a variação do tom de cor foi mais exacerbada para as mechas tratadas com a formulação em pH 1,0. O teor de triptofano foi inferior nas mechas alisadas com a formulação pH 1,0. Para o teste de DSC e Raman, ambas as mechas tratadas apresentaram modificações nas suas estruturas. As fibras alisadas e expostas à radiação UV apresentaram danos maiores nas cutículas, e certa proteção na degradação de proteínas em relação aquelas sem tratamento e irradiadas ao UV. Considerando as reaplicações do produto alisante ácido, quanto maior o número de aplicações, mais alinhadas e seladas tornaram se as fibras, mas mais rígida e suscetível à quebra ficaram. Devemos considerar a importância do valor do pH da formulação no impacto do alisamento e dano da fibra capilar. / Hair straightening products are widely used in Brazil by the female public. However, these procedures can cause damage to the hair shaft and to professional´s and client´s health. Chemical straighteners can be divided into two groups: alkaline and acid. Alkaline straighteners has a very high pH value (> 9.0) and the straightening process is due to the break followed by reorganization of the disulfide bridges (S-S) present in the keratin, a structural protein of the hair shaft. Some examples of alkaline straighteners are ammonium thioglycolate and sodium or guanidine hydroxides. On the other hand, acid straighteners like formaldehyde, glyoxylic acid, and their associated, present a low pH value (≥ 2.0), which causes a rearranging within the fiber, and sometimes creates a film on the surface of the hair. Nowadays, the glyoxylic acid associated with carbocysteine and amino acids (INCI - International Nomenclature of Cosmetic Ingredient nomenclature presented in parentheses) (Glyoxyloyl Carbocysteine (and) Glyoxyloyl Keratin Aminoacids (and) Water) is the only acid straightener permitted. Therefore, the objective of this work is to study the effect of this acid straightener, incorporated into oil in water (o/w) base emulsions at two different pH values 1.0 and 2.0 ( with reapplication) on the mechanical and physicochemical properties of the hair shaft. Also, the impact of UV radiation in straightened tresses. In the experiments conducted, it was possible to observe that tresses treated with the emulsion at pH 1.0 had a better result on the alignment and the straightening capacity, improving the combing test (59.4%/), while the tresses with the formulation at pH 2.0, 33.0%. However, the tensile strength, to pH 1.0 decreased by 16.0% and to pH 2.0 only 9.0%. As for color, the difference when compared with virgin hair it was major at pH 1.0. The tryptophan content also was lower in tresses treated at pH 1, 0. For the DSC and Raman analyzes all the treated tresses presented modifications in their structure. Straightened strands exposed to radiation had major damage in the cuticles, and some protection in proteins degradation compared to untreated tresses exposed to radiation. Considering the reapplications of the straightening product, as higher the number of applications more aligned and sealed it becomes, however the hair fiber becomes stiffer and susceptible to breakage. Thats why we should consider the importance of the pH value in the product, and the impact of straightening and damage of the hai fiber.

A aparência dos cabelos é de fundamental importância na sociedade atual. Estando em moda, cabelos mais lisos e com menos volume, os consumidores que antes os alisavam com produtos químicos e força mecânica, passaram a utilizar um tratamento térmico, além do secador de cabelos: as piastras (\"chapinhas\") que atuam em valores de temperatura ao redor de 230°C. Esse procedimento ocasiona além dos danos mecânicos e químicos também dano térmico, tornando os cabelos ainda mais fragilizados. O escopo deste estudo foi avaliar o dano na fibra capilar, de amostras não tratadas e nas que receberam aplicação de alisantes/relaxantes tradicionais e alternativos. O estudo foi dividido em cinco capítulos que avaliam: aplicação dos alisantes/relaxantes com ingredientes ativos distintos; danos mecânicos, perda Protéica; análise térmica e microscopia eletrônica de varredura. As amostras de cabelo utilizadas em todos os estudos foram tratadas como descrito no primeiro capítulo. Foram aplicados produtos comerciais contendo os seguintes ingredientes ativos: Hidróxido de Sódio, Tioglicolato de Amônio, Hidróxido de Guanidina (reação de hidróxido de cálcio com carbonato de guanidina), formaldeído e ácido glioxílico isolado e em combinação com carbocisteína. O uso de formaldeído e ácido glioxilico em formulações de alisantes/relaxantes está proibido pela Agência Nacional de Vigilância Sanitária. Todos os produtos aplicados alisaram os cabelos; os procedimentos que utilizaram a piastra tornaram os fios mais lisos. Os alisantes/relaxantes à base de ácido glioxilico e formaldeído reduziram de forma expressiva a tensão de ruptura dos cabelos tornando-os mais frágeis. A maior perda protéica foi observada na amostra tratada com carbocisteína (1,74 mg/g cabelo). Nos estudos de análise térmica, na fase de desidratação a amostra tratada com carbocisteína apresentou maior perda de massa (15,17%); na fase de denaturação da proteína, a tratada com hidróxido de sódio (51,06%); e na fase de eliminação do material carbonáceo, todas as amostras apresentaram perda de massa maior que a amostra não tratada; as menores temperaturas de pico foram as das amostras sem tratamento alisante (630°C) e ácido glioxílico (640°C). Observando-se as imagens de microscopia eletrônica nota-se modificação nas bordas das cutículas das amostras indicando que sofreram agressão; o hidróxido de guanidina deixou adicionalmente resíduo; as amostras tratadas com ácido glioxílico e formaldeído apresentaram a formação de filme superficial como um \"envelopamento\" da fibra. Os resultados sugerem que não há predominância de um procedimento mais danoso que os demais; porém os que utilizaram a piastra (alisamentos/relaxamento ácidos) acentuaram os danos. / The appearance of the hair is of fundamental importance in today\'s society. Being in fashion, hair straight and with less volume, consumers that before straighted hair with chemicals products and mechanical strength began to use a heat treatment, in addition to hair dryers: the hot plates (\"chapinhas\") acting on temperature values around 230°C. This procedure causes not only mechanical and chemical damage but also thermal one, making the hair more fragile. The scope of this study was to evaluate the damage to the hair fiber, in untreated samples and these receiving straighteners/relaxers application of traditional and alternative products.The study was divided into five chapters that evaluated: application of straighteners/relaxers with different active ingredients; mechanical damage, protein loss; thermal analysis and scanning electron microscopy. The hair samples used in all studies were treated as described in the chapter one. Commercial products containing the following active ingredients were used: Sodium Hydroxide, Ammonium Thioglycolate, Guanidine Hydroxide (calcium hydroxide reaction with guanidine carbonate), Formaldehyde and Glyoxylic Acid alone and in combination with Carbocysteine. The use of Formaldehyde andGlyoxylicAcid in straightening/relaxing formulations are prohibited by the National Agency for Sanitary Vigilance. All applied products, straight the hair samples; the procedures that used the hot plates become the hair more straight. The straightening/relaxing based on Glyoxylic Acid and Formaldehyde reduced significantly the hair break point making them more fragile. Most protein loss was observed in the sample treated with Carbocysteine (1.74mg/g hair).In the thermal analysis studies at the dewatering stage, Carbocystein treated samples showed greater weight loss(15.17%), at the protein denaturation stage this treated with Sodium Hydroxide (51.06%) and in the carbonaceous material elimination phase all samples showed mass loss greater than the untreated sample;. The lower peak temperatures were observed in the samples without treatment (630°C) and with Glyoxylic Acid (640°C). Observing the images of electron microscopy is noted the change in the cuticle aspect of the samples showing that the edges were damaged, Guanidine Hydroxide, left further residue: the samples treated with Glyoxylic Acid and Formaldehyde showed the formation of surface film as an \"enveloping\" fiber. The results suggest that there is not a predominance of a more harmful treatment than other, but those using hot plates(straightening/relaxing acids) emphasize the damage.

A aparência dos cabelos é de fundamental importância na sociedade atual. Estando em moda, cabelos mais lisos e com menos volume, os consumidores que antes os alisavam com produtos químicos e força mecânica, passaram a utilizar um tratamento térmico, além do secador de cabelos: as piastras (\"chapinhas\") que atuam em valores de temperatura ao redor de 230°C. Esse procedimento ocasiona além dos danos mecânicos e químicos também dano térmico, tornando os cabelos ainda mais fragilizados. O escopo deste estudo foi avaliar o dano na fibra capilar, de amostras não tratadas e nas que receberam aplicação de alisantes/relaxantes tradicionais e alternativos. O estudo foi dividido em cinco capítulos que avaliam: aplicação dos alisantes/relaxantes com ingredientes ativos distintos; danos mecânicos, perda Protéica; análise térmica e microscopia eletrônica de varredura. As amostras de cabelo utilizadas em todos os estudos foram tratadas como descrito no primeiro capítulo. Foram aplicados produtos comerciais contendo os seguintes ingredientes ativos: Hidróxido de Sódio, Tioglicolato de Amônio, Hidróxido de Guanidina (reação de hidróxido de cálcio com carbonato de guanidina), formaldeído e ácido glioxílico isolado e em combinação com carbocisteína. O uso de formaldeído e ácido glioxilico em formulações de alisantes/relaxantes está proibido pela Agência Nacional de Vigilância Sanitária. Todos os produtos aplicados alisaram os cabelos; os procedimentos que utilizaram a piastra tornaram os fios mais lisos. Os alisantes/relaxantes à base de ácido glioxilico e formaldeído reduziram de forma expressiva a tensão de ruptura dos cabelos tornando-os mais frágeis. A maior perda protéica foi observada na amostra tratada com carbocisteína (1,74 mg/g cabelo). Nos estudos de análise térmica, na fase de desidratação a amostra tratada com carbocisteína apresentou maior perda de massa (15,17%); na fase de denaturação da proteína, a tratada com hidróxido de sódio (51,06%); e na fase de eliminação do material carbonáceo, todas as amostras apresentaram perda de massa maior que a amostra não tratada; as menores temperaturas de pico foram as das amostras sem tratamento alisante (630°C) e ácido glioxílico (640°C). Observando-se as imagens de microscopia eletrônica nota-se modificação nas bordas das cutículas das amostras indicando que sofreram agressão; o hidróxido de guanidina deixou adicionalmente resíduo; as amostras tratadas com ácido glioxílico e formaldeído apresentaram a formação de filme superficial como um \"envelopamento\" da fibra. Os resultados sugerem que não há predominância de um procedimento mais danoso que os demais; porém os que utilizaram a piastra (alisamentos/relaxamento ácidos) acentuaram os danos. / The appearance of the hair is of fundamental importance in today\'s society. Being in fashion, hair straight and with less volume, consumers that before straighted hair with chemicals products and mechanical strength began to use a heat treatment, in addition to hair dryers: the hot plates (\"chapinhas\") acting on temperature values around 230°C. This procedure causes not only mechanical and chemical damage but also thermal one, making the hair more fragile. The scope of this study was to evaluate the damage to the hair fiber, in untreated samples and these receiving straighteners/relaxers application of traditional and alternative products.The study was divided into five chapters that evaluated: application of straighteners/relaxers with different active ingredients; mechanical damage, protein loss; thermal analysis and scanning electron microscopy. The hair samples used in all studies were treated as described in the chapter one. Commercial products containing the following active ingredients were used: Sodium Hydroxide, Ammonium Thioglycolate, Guanidine Hydroxide (calcium hydroxide reaction with guanidine carbonate), Formaldehyde and Glyoxylic Acid alone and in combination with Carbocysteine. The use of Formaldehyde andGlyoxylicAcid in straightening/relaxing formulations are prohibited by the National Agency for Sanitary Vigilance. All applied products, straight the hair samples; the procedures that used the hot plates become the hair more straight. The straightening/relaxing based on Glyoxylic Acid and Formaldehyde reduced significantly the hair break point making them more fragile. Most protein loss was observed in the sample treated with Carbocysteine (1.74mg/g hair).In the thermal analysis studies at the dewatering stage, Carbocystein treated samples showed greater weight loss(15.17%), at the protein denaturation stage this treated with Sodium Hydroxide (51.06%) and in the carbonaceous material elimination phase all samples showed mass loss greater than the untreated sample;. The lower peak temperatures were observed in the samples without treatment (630°C) and with Glyoxylic Acid (640°C). Observing the images of electron microscopy is noted the change in the cuticle aspect of the samples showing that the edges were damaged, Guanidine Hydroxide, left further residue: the samples treated with Glyoxylic Acid and Formaldehyde showed the formation of surface film as an \"enveloping\" fiber. The results suggest that there is not a predominance of a more harmful treatment than other, but those using hot plates(straightening/relaxing acids) emphasize the damage.

E-glass has been widely used as a reinforcing material for years, especially as a plastic reinforcer in the production of GRP (Glass Reinforced Plastic). Failure of GRP materials under stress came in to the picture quite recently. Since then studies have been conducted in an attempt to understand the causes and the underlying behaviour. / Except for the last section of the research (analysis using a kinetic approach) where glass fibre was cut out to weigh approximately 1.0g, standard sized specimens were soaked in the required acid solutions of desired concentrations for varying temperatures and time frames. Wherever tensile strength retention was measured, LLOYD instrument was employed. Leaching of the cations were analysed using Inductively Coupled Plasma – Optical Emission Spectroscopy (ICP-OES and also know and ICP-AES). / The scope of this project can be divided in to four sections; first section involved investigating the effects of malonic acid. The study of malonic acid was narrowed to investigating the trend in strength retention. A rapid strength loss was observed initially followed by a much steady decline in the strength. However the continuation of the loss of strength was unmistakable throughout the time period of exposure. Furthermore, temperature can be observed as a facilitating factor in this degradation reaction. / Secondly the corrosive effect of glyoxylic acid on E-glass fibre was studied. This was explored at two different temperatures for two specific time frames using various concentrations of the acid of interest. The influence of this acid on the glass fibre was found out in terms of strength retention and loss of cations from the glass matrix. The mildness of this acid was accentuated by the fact that 70% or more of the strength was retained at all the conditions employed. A minima in strength retention was observed at 2M acid concentration similar to the trends observed in the past (Betz and Jones 2003 and Jones and Chandler 1986). Leaching of cations reflected this trend. The large strength retention could be related to the fewer amounts of Ca and K leached from the glass matrix (Kumosa and Qui, 1997). Similar to malonic acid, an unusually large amount of B was leached out that could be due to the favourable orientation of the anion with the trivalent ions during the complex formation. Yet again temperature was found to enhance the degradation process. / Next the extent of passivation (if any) showed by malonic acid was investigated using E-glass fibre pre-treated in 5M malonic acid and post treated in known corrosive acids hydrochloric acid and oxalic acid. Passivation of malonic acid was put to test through examination of strength retention of the fibres under these conditions. This segment was carried out as an extension of a finding (a behaviour synonymous to passivation) shown by malonic that surfaced the previous year by the present researcher. Increasing the pre-treatment time showed a great improvement in the retained strength for all the post-treatment acid mediums. Furthermore, while Jones and Betz (2004) featured 20-40% strength retention within a short time frame in 3M HCl, the immense amount of strength retention (60-70%) preceding pre-treatment should definitely be noted. Similarly strength retention of about 80% was observed when post-treated with the severely corrosive oxalic acid. Hence its is clear that passivation can be induced through prolonged pre-treatment in 5M malonic acid that could inhibit the attack of corrosive acid at least for a period of time. / The last fragment of the study focussed on understanding and working out the mechanism behind the reactions between the E-glass fibre and acid medium in terms of kinetics. The acids utilized were 1.5M malonic acid and 3M glyoxylic acid and the assessments were made through the analysis of the weight changes brought about by the acid medium at various temperatures and time frames. In addition leaching patterns of cations were evaluated as this could contribute in achieving the objective. Maximum weight loss reached 4% in glyoxylic acid while that for malonic acid exceeded 20%. The general trend was that the glass fibres lost weight in both acids for a period of time followed by an evident weight gain. Furthermore the weight loss results fit the first order rate law. While the leaching of cations reflects the weight loss for the shorter time frames, steady loss of ions was visible even for the longer time frames where the weight has increased. The weight gain could be explained in terms of binding of anions to certain cations on the glass surface, accounting for the hindrance in the loss of cations at the longer time frames as well. About 50% of weight loss was associated to Ca while 20% was to Al, leaving 6% to B where as the rest of the ions had shown almost insignificant contribution to the weight loss.

In order to demonstrate the influence of morphine on the developmental localization of regenerated noradrenergic fibers in rat cerebellum, a glyoxylic histofluorescent method and radiometric assay for norepinephrine (NE) were utilized. An initial reduction of NE in the cerebellum after 6-hydroxydopa [6-OHDOPA; 60 µg/g intraperitoneally (i.p.)] was followed by a return to control levels at 3 days, and an elevation above control levels at 7 days. The initial rates of recovery of NE in the cerebellum of the 6-OHDOPA group of rats and the group receiving morphine (20 µg/g i.p.) in combination with 6-OHDOPA were identical up to 7 days. However, by 14 days NE content was further elevated in the cerebellum of the morphine+6-OHDOPA group. Histofluorescent microscopic observations of the cerebellar cortex correlated with the biochemical findings. A reduction in cerebellar NE content at 3 days was associated with a reduction in the number of visible histofluorescent fibers in the cerebellar cortex. By 7 days the relative number of fibers in the 6-OHDOPA groups was similar to that seen in the control group, but by 9 days the relative number of fluorescent fibers in the cerebellar cortex was increased above control. By 13 days there was a further increase in the relative number of fluorescent fibers in the cerebellar cortex of the morphine+6-OHDOPA group, as compared to the group treated with 6-OHDOPA alone. These findings provide an anatomic correlate for recovery of noradrenergic fibers after 6-OHDOPA, and demonstrate an action of morphine in enhancing regenerative sprouting.

I present detailed mechanistic analysis on the chemistry of glyoxylate as it pertains to forming biologically relevant molecules on the Hadean Earth. Chemistry covered includes: 1) the dimerization of glyoxylate to form dihydroxyfumarate(DHF), a heretofore unknown reaction, important to substantiating Eschenmoser's glyoxylate scenario. 2) Formation of sugars from polymerization of glyoxylate. 3) Formation of tartrate and sugar acids from high pH reactions of DHF. 4) Formation of glycine polypeptides from glyoxylate by transamination and coupling promoted by hexamethylenetetramine. 5) Formation of glyoxylate under conditions which could be plausibly found on the early earth.

Atmospheric aerosols affect climate change by altering the energy balance of the atmosphere, and public health due to their variable chemical composition, size, and shape. While the formation of secondary organic aerosol (SOA) from gas phase precursors is relatively well understood, it does not account for the abundance of SOA observed during field measurements. Recently it has become apparent that in-aerosol aqueous chemical reactions likely provide some of the missing sources of SOA production, and many studies of aqueous phase processes are underway. This work explores the fates of the simplest 2-oxocarboxylic acids, glyoxylic acid (GA) and pyruvic acid (PA), under simulated solar irradiation in the aqueous phase. Field measurements have revealed that mono-, di-, and oxocarboxylic acids are abundant species present in atmospheric waters. Of particular interest are 2-oxocarboxylic acids because their conjugated carbonyl moieties result in significant UV-visible absorption above 300 nm, allowing absorption of sunlight in the lower troposphere, thereby initiating radical photochemistry and leading to formation of SOA. In Chapter 2 of this work, GA is demonstrated to primarily undergo α-cleavage, producing CO, CO2, formic acid, and the key SOA precursor glyoxal. Trace amounts of oxalic acid and tartaric acid are also quantified. Additionally, the dark thermal aging of glyoxylic acid photoproducts, studied by UV-visible and fluorescence spectroscopies, reveals that the optical properties of the solutions are altered radically by the glyoxal produced. The optical properties display periodicity during photolytic-dark cycles, reflecting behavior expected for aerosols during nighttime and daytime cycles. In contrast, Chapter 3 shows that PA photoreacts via a proton-coupled electron transfer (PCET) mechanism that produces CO2 and organic acids of increased complexity with 6 to 8 carbons. A combination of analytical techniques including 1H and 13C NMR; 13C gCOSY NMR; mass spectrometry; chromatography; and isotope substitutions allows the organic products to be identified as: 2,3-dimethyltartaric acid; 2-hydroxy-2-((3-oxobutan-2-yl)oxy)propanoic acid; and the quasi-intermediate 2-(1-carboxy-1-hydroxyethoxy)-2-methyl-3-oxobutanoic acid. In Chapter 4, PA irradiation is also shown to consume dissolved oxygen so fast that solutions become depleted within a few minutes depending on reaction conditions. This fast process directly produces the atmospheric oxidant singlet oxygen, which enhances the oxidizing capacity of the atmosphere. Additionally, PA photochemistry only proceeds under very acidic conditions (pH ≤ 3.5), like those in most atmospheric aerosols. Finally, we require a thorough understanding of the behavior of 2-oxocarboxylic acids at the air-water interface of aerosols because much of the GA and PA present in the atmosphere is produced in the gas phase and needs to partition into the aqueous phase to undergo photoreaction. Therefore, Chapter 5 uses surface sensitive online electrospray ionization mass spectrometry (OESI-MS) to demonstrate that carboxylic acids delivered from the gas phase onto the surface of aqueous microdroplets display enhanced acidities relative to bulk water solutions. This work demonstrates that aqueous photolysis is a very competitive atmospheric fate for both GA and PA. It also shows that these photoreactions are capable of contributing substantially to SOA formation by building chemical complexity and forming oxidants directly.

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