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A new Ru(ii) complex was synthesized, fully characterized and applied as electrocatalyst for CO2 reduction. The role of the reaction medium and the carboxylate ligand on the product selectivity was elucidated.

RESUMO Introdução: As queimaduras são traumas graves, que geram 100 mil atendimentos hospitalares por ano, no Brasil. As Unidades de Queimados são fundamentais para o tratamento desses pacientes e a produção de conhecimento sobre o tema. Método: O estudo estabeleceu o perfil de atendimento em cada ano de funcionamento da unidade no período de 2009 a 2012, e comparou, entre esses anos, a quantidade de pacientes internados, a procedência, os graus de queimadura, a idade, a superfície corporal queimada, os dias de internação, os tipos de procedimentos cirúrgicos, os agentes e a mortalidade. Para avaliação das possíveis associações, foi utilizado o teste do Qui-quadrado. Resultados: Foram internados 321 pacientes. Em 2009, 70% dos pacientes apresentavam queimadura de II grau e, em 2012, 66% dos pacientes tinham queimadura de III grau. Em 2009, 37% vieram referenciados de outros serviços, e em 2012, 72%. A idade média dos pacientes foi de 29 anos em 2009 e 44 anos, em 2012. A superfície corporal queimada no início era de 13%, e em 2012, foi 8%. O tempo de internação subiu de 11 para 21 dias. Em 2009, realizaram-se 50 procedimentos cirúrgicos. Em 2012, foram 103. O agente causal mais encontrado foram os líquidos inflamáveis e a mortalidade global caiu de 7% para 4%, ao longo dos anos. Conclusão: Houve um aumento na quantidade de pacientes referenciados e complexos, com queimaduras de maior grau, exigindo mais procedimentos e maior hospitalização, ao longo dos anos. A taxa de mortalidade diminuiu, refletindo melhora técnica da Unidade, que se estabeleceu como referência regional no tratamento de queimados. ABSTRACT Introduction: Burns constitute severe trauma and account for 100,000 hospital visits per year in Brazil. Burns units are essential for the treatment of these patients and the generation of knowledge on this subject. Method: This study established the annual profile of burn unit attendance between 2009 and 2012. During these years of activity, we compared the number of hospitalized patients, patient origin, burn degree, age, burn body surface area, days of hospitalization, types of surgical procedures, agents, and mortality. Possible combinations were evaluated with the chi-square test. Results: A total of 321 patients were hospitalized. In 2009, 70% of the patients presented secon-degree burns; in 2012, 66% of the patients presented third-degree burns. In 2009, 37% of the patients were referred to other services; in 2012, 72% were referred. The average patient age was 29 years old in 2009 and 44 years old in 2012. Burn body surface was 13% in 2009 and 8% in 2012. Hospitalization time increased from 11 to 21 days. A total of 50 surgical procedures were performed in 2009, while 103 were performed in 2012. Flammable liquids were the most commonly observed causal agents. The overall mortality rate decreased from 7% to 4% over the study period. Conclusion: There was an increase in the number of referred and complex patients with higher degree burns who required longer hospital stays and a greater number of procedures over the years. The decreased mortality rate reflected the technical improvement of the unit that was established as a regional reference for the treatment of burn victims.

Control of underactuated systems with non-holonomic constraints has been an issue of interest in recent years. These systems are hard to control because their linearization makes them uncontrollable and current approaches generally involve complex calculations. In this manuscript, a controller for trajectory tracking and positioning for a second-order chained form system using a simple approach based on linear algebra is proposed. The control law is formulated by setting two of the six variables trajectories, while the other four are calculated assuming the equations system has an exact solution, and ensuring the error tends to zero. The stability of the proposed control system is demonstrated through the Khalil Lemma, and simulations show the performance of the controller.

In the present work, the synthesis, characterization, antifungal activity, molecular docking study and in silico approach of five thiosemicarbazone derivatives and their corresponding zinc(II) complexes are described. The compounds were characterized by elemental analysis, IR, UV-Vis and NMR spectroscopic measurements, molar conductivity measurements, emission spectra, high-resolution mass spectrometry and X ray study. The antifungal activity of the free ligands and synthesized compounds was preliminarily evaluated against Candida albicans (ATCC 90028), Candida tropicalis (ATCC 13803) and Candida glabrata (ATCC 2001), by the minimum inhibitory concentration (MIC) assay. Two complexes, 4 (MIC = 3.18 to 6.37 μM) and 5 (MIC = 25.95 μM for all) showed promising results, being highly active against all strains evaluated. The X-ray analyses shown that the complex 2 crystallizes in the centrosymmetric space group P2

A new ruthenium polypyridyl complex, [Ru(bpy)2(acpy)]+ (acpy = 2-pyridylacetate, bpy = 2,2′-bipyridine), was synthesized and fully characterized. Distinct from the previously reported analog, [Ru(bpy)2(pic)]+ (pic = 2-pyridylcarboxylate), the new complex is unstable under aerobic conditions and undergoes oxidation to yield the corresponding α-keto-2-pyridyl-acetate (acpyoxi) coordinated to the RuII center. The reaction is one of the few examples of C–H activation at mild conditions using O2 as the primary oxidant and can provide mechanistic insights with important implications for catalysis. Theoretical and experimental investigations of this aerobic oxidative transformation indicate that it takes place in two steps, first producing the α-hydroxo-2-pyridyl-acetate analog and then the final product. The observed rate constant for the first oxidation was in the order of 10−2 h−1. The reaction is hindered in the presence of coordinating solvents indicating the role of the metal center in the process. Theoretical calculations at the M06-L level of theory were performed for multiple reaction pathways in order to gain insights into the most probable mechanism. Our results indicate that O2 binding to [Ru(bpy)2(acpy)]+ is favored by the relative instability of the six-ring chelate formed by the acpy ligand and the resulting RuIII-OO˙− superoxo is stabilized by the carboxylate group in the coordination sphere. C–H activation by this species involves high activation free energies (ΔG‡ = 41.1 kcal mol−1), thus the formation of a diruthenium μ-peroxo intermediate, [(RuIII(bpy)2(O-acpy))2O2]2+via interaction of a second [Ru(bpy)2(acpy)]+ was examined as an alternative pathway. The dimer yields two RuIVO centers with a low ΔG‡ of 2.3 kcal mol−1. The resulting RuIVO species can activate C–H bonds in acpy (ΔG‡ = 23.1 kcal mol−1) to produce the coordinated α-hydroxo-2-pyridylacetate. Further oxidation of this intermediate leads to the α-keto-2-pyridyl-acetate product. The findings provide new insights into the mechanism of C–H activation catalyzed by transition-metal complexes using O2 as the sole oxygen source.

This work describes the preparation of a new thiosemicarbazone derivative, (Z)-N-ethyl-2-(6-oxo-1,10-phenanthrolin-5(6H)-ylidene)hydrazinecarbothioamide (phet) and its respective Re(i) tricarbonyl chloro complex, fac-[ReCl(CO)3(phet)]. The spectroscopic, photophysical and electrochemical properties of the new complex were fully investigated through steady state and time-resolved techniques along with computational calculations. In fac-[ReCl(CO)3(phet)], the new ligand is coordinated to the metal center through the pyridyl rings of the phenanthroline moiety. The unbound electron pairs in the S atom of the bending thiosemicarbazone group induce new low energy lying electronic transitions. Consequently, enhanced visible light absorption up to 550 nm is observed in acetonitrile due to the overlap between MLCTRe→phet and ILphet(n→π*) transitions. The absorption bands and emission quantum yields of fac-[ReCl(CO)3(phet)] are sensitive to proton concentration due to an acid-basic equilibrium in the N atoms of the thiosemicarbazone. Proton dissociation constants of 10.0 ± 0.1 and 11.4 ± 0.2 were determined respectively for the ground and excited states of the new complex. Spectral changes could also be observed in the presence of Zn2+ cations which can be further explored for sensing applications. The electrochemical behavior of the new complex was studied in detail, revealing up to four one electron reduction processes in the range from 0 to -2.4 V vs. Fc+/Fc. With support of DFT calculations, the first three processes are ascribed to the reduction of the coordinated phet ligand followed by the ReI/0 reduction and consequent Cl- release. The new complex was able to act as an electrocatalyst for CO2 reduction into CO (Eonset = -1.92 V vs. Fc+/Fc), with a turnover frequency of 2.81 s-1 and turnover number of 24 ± 1 in anhydrous acetonitrile, being the first Re(i) tricarbonyl complex with a thiosemicarbazone derivative described for this goal. The detailed characterization carried out here can drive the development of new Re(i)-thiosemicarbazone derivatives for different applications.

CAPES - Coordenação de Aperfeiçoamento de Pessoal de Nível Superior IQUFU - Instituto de Química da Universidade Federal de Uberlândia Compostos de coordenação são capazes de catalisar reações de grande interesse tecnológico, como por exemplo, a oxidação da água ou a redução de CO2. Neste trabalho, o novo complexo de Ru(II) [RuCl(trpy)(acpy)], trpy = 2,2’:6’,2”-terpiridina, acpy = 2-piridilacetato foi sintetizado e suas propriedades espectroscópicas, eletroquímicas e catalíticas exploradas em detalhe. Espectros de ressonância magnética nuclear de hidrogênio e espectroscopia vibracional no infravermelho foram empregados para comprovação estrutural do composto e sugerem a coordenação bidentada do ligante acpy. Ensaios espectrofotométricos, corroborados por simulações teóricas, revelam que as transições eletrônicas de menor energia são dominadas por transferências de carga do metal para o ligante (MLCT). Ensaios eletroquímicos revelam que em potenciais anódicos, o pico redox observado em 0.006 V vs Fc/Fc+, corresponde ao par redox RuII/III. Em potenciais catódicos, dois picos de redução são observados em -1.95 V e -2.20 V vs Fc/Fc+ sendo atribuídos à redução do ligante trpy e do centro metálico, respectivamente. Sob condições anidras e atmosfera de CO2 o complexo apresentou atividade eletrocatalítica convertendo CO2 à CO com um TONCO = 12 e kcat = 1.5 s-1. Na presença de 1% de água (v/v), os valores de TONCO = 21 e kcat = 2.0 s-1 foram encontrados e, adicionalmente, formato foi detectado com um TONHCOO- = 7. As eficiências faradaicas obtidas com 1% de água foram de 76% e 20%, respectivamente para CO e formato. Experimentos de espectroeletroquímica na região do infravermelho e sob atmosfera de CO2 revelam a possível formação do metalocarboxilato (Ru-COO-). Na presença de água a possível quebra do quelato foi observada. Coordination compounds are capable of catalysing reactions of great technological interest, for example, the watter splitting or the CO2 reduction. In this project, the new Ru(II) complex, [RuCl(trpy)(acpy)], trpy = 2,2’:6’,2”-terpyridine, acpy = 2-pyridylacetate was synthesized and its spectroscopic, electrochemical and catalytic properties explored in detail. Hydrogen nuclear magnetic resonance and vibrational infrared spectra were used to prove the structure of compound and suggest the bidentated coordination of acpy ligand. Spectrophotometric essays, corroborated by theoretical simulations, reveal that lower electronic transitions are dominated by metal-ligand charge transfer (MLCT). Electrochemical studies revealed that in anodic potentials the peak observed at 0.006 V vs Fc/Fc+ correspond to the redox pair RuII/III. In cathodic potentials, two reduction peaks were detected at -1.95 V and -2.20 V vs Fc/Fc+, being attributed to the trpy and metal center reductions respectively. Under anhydrous conditions and a CO2 atmosphere, the complex presented an electrocatalytic activity converting CO2 to CO with a TONCO = 12 and kcat = 1.5 s-1. In the presence of 1% water (v/v), the TONCO = 21 and kcat = 2.0 s-1 were obtained and, additionally, formate was detected with TONHCOO- = 7. The faradaic efficiencies obtained with 1% water were 76% and 20%, respectively for CO and formate. Spectroelectrochemical experiments in the infrared range and under a CO2 atmosphere reveal the possible formation of the metallocarboxylate (Ru-COO-). In the presence of water the possible chelate breakdown was observed. Tese (Doutorado)

Control of underactuated systems with non-holonomic constraints has been an issue of interest in recent years. These systems are hard to control because their linearization makes them uncontrollable and current approaches generally involve complex calculations.In this manuscript,a controller for trajectory tracking and positioning for a second-order chained form system using a simple approach based on linear algebra is proposed.The control law is formulated by setting two of the six variables trajectories, while the other four are calculated assuming the equations system has an exact solution, and ensuring the error tendsto zero. The stability of the proposed control system is demonstrated through the KhalilLemma, and simulations show theperformance of the controller. Fil: Rodriguez Aguilar, Leandro Pedro Faustino. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - San Juan; Argentina. Universidad Nacional de San Juan. Facultad de Ingeniería. Instituto de Ingeniería Química; Argentina Fil: Fernández Puchol, María Cecilia. Universidad Nacional de San Juan. Facultad de Ingeniería. Instituto de Ingeniería Química; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - San Juan; Argentina Fil: Sanchez, Mabel Cristina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Planta Piloto de Ingeniería Química. Universidad Nacional del Sur. Planta Piloto de Ingeniería Química; Argentina Fil: Scaglia, Gustavo Juan Eduardo. Universidad Nacional de San Juan. Facultad de Ingeniería. Instituto de Ingeniería Química; Argentina. Universidad Nacional de San Juan. Facultad de Ingeniería. Instituto de Ingeniería Química; Argentina

The different types of sutures utilized in plications and for correction of diastasis during abdominoplasty are reviewed and discussed. Because correction of abdominal deformities also involves fascia and muscle advancement, this review also covers the suture materials used in muscle advancement. The selection of specific techniques to treat different types of abdominal wall deformity is also considered. This is important, because the outcome when correcting these deformities depends not only on suture materials but also on employing the optimum technique. A PubMed/Medline search was performed with the following search terms: rectus diastasis, diastasis recti, diastasis recti abdominis, correction of rectus diastasis, abdominoplasty. Relevant articles identifying the type of suture (rapidly absorbable, slowly absorbable, nonabsorbable), monofilament or multifilament sutures, antibiotic-coated sutures, and barbed sutures were evaluated. In addition, articles about surgical technique comparing continuous and interrupted sutures, in both the anterior and posterior aponeurosis, to correct rectus diastasis are discussed. Efficacy of suture materials was evaluated based on the long-term results and recurrence rates reported in these articles. The current literature provides sufficient data to recommend a single-layer continuous suture, with slowly absorbable sutures of 0 polydioxanone or 2-0 nylon, for correction of abdominal diastasis. An interrupted triangular suture is a good alternative to correct the vertical elongation of the myoaponeurotic layer that occurs after pregnancy.

Este trabajo presenta una novedosa metodología para la optimización dinámica del proceso de producción de biodiesel a partir de aceites vegetales en modo discontinuo. La metodología propuesta tiene la particularidad de emplear la serie de Fourier para la parametrización de la acción de control, y algoritmos evolutivos para la optimización de parámetros. Las ventajas principales de esta estrategia son, por un lado, que los perfiles obtenidos son suaves, es decir, continuos y diferenciables, por lo tanto pueden implementarse directamente en sistemas reales, sin necesidad de filtrar o suavizar la señal de control; por otro lado, se requiere una mínima cantidad de parámetros para la optimización, evitando la sobre-parametrización, la cual puede disminuir la calidad de la respuesta. Los algoritmos propuestos han sido evaluados a través de simulaciones, obteniendo resultados muy satisfactorios comparados con los existentes en bibliografía. This work presents a novel methodology for the dynamic optimization of the biodiesel production process from vegetable oils in discontinuous mode. The proposed methodology has the particularity of using the Fourier series for the parameterization of the control action, and evolutionary algorithms for the optimization of parameters. The main advantages of this strategy are, on the one hand, that the profiles obtained are smooth, that is, continuous and differentiable, therefore they can be directly implemented in real systems, without the need to filter or soften the control signal; on the other hand, a minimum amount of parameters is required for optimization, avoiding over-parameterization, which can decrease the quality of the response. The proposed algorithms have been evaluated through simulations, obtaining very satisfactory results compared to those published in the literature. Fil: Pantano, Maria Nadia. Universidad Nacional de San Juan. Facultad de Ingeniería. Instituto de Ingeniería Química; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Fernández Puchol, María Cecilia. Universidad Nacional de San Juan. Facultad de Ingeniería. Instituto de Ingeniería Química; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Rodriguez Aguilar, Leandro Pedro Faustino. Universidad Nacional de San Juan. Facultad de Ingeniería. Instituto de Ingeniería Química; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina Fil: Scaglia, Gustavo Juan Eduardo. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de San Juan. Facultad de Ingeniería. Instituto de Ingeniería Química; Argentina

The components separation technique (CS) is used for the reconstruction of complex abdominal wall defects. Release and undermining of the rectus abdominis muscle (RAM) and external oblique muscle (EOM) decrease tension on the abdominal midline, reducing recurrence of ventral hernia, but causes major changes in the physiology of abdominal wall. The purpose of the study was to determine which muscle release and undermining produces the lowest tension on the midline.Twenty fresh cadavers were dissected and the anterior and posterior layers of the rectus sheath were isolated in the midline. The forces necessary to advance the layers of the rectus sheath to the mid abdomen were measured bilaterally at two points located 3 cm above and 2 cm below the umbilicus, and at 3 different stages: before any muscle release; after release and undermining of the right RAM and left EOM; and after release and undermining of the left RAM and right EOM. Comparisons of tensile forces were conducted separately for the different muscles involved, layers of the rectus sheath, measurement points, and stages of separation.Tension on the abdominal midline after the release and undermining of both the RAM and EOM was reduced by 56% (p0.05), 42% after the release and undermining of the EOM alone (p0.05), and 35% after release and undermining of the RAM alone (p0.05).Release and undermining of the EOM by CS led to lower tension on the abdominal midline compared to that associated with the release of the RAM alone.

Immobilization of Re(I) CO2 reduction photocatalysts on metal oxide surfaces is an interesting approach to improve their stability and recyclability. In this work, we describe the photocatalytic activity of two Re(I) complexes (fac-[Re(NN)(CO)3(Cl)], NN = 4,4'-dicarboxylic acid-2,2'-bipyridine, 1, or 5,6-dione-1,10-phenantroline, 2) on the surface of hexaniobate nanoscrolls. After adsorption, the turnover number for CO production (TONCO) in DMF/TEOA of 1 was increased from 9 to 58, which is 20% higher than that observed on TiO2, being among the highest reported values for a Re(I)-based photocatalyst under visible light irradiation without any sensitizer. The complex 2 is inactive in solution under visible-light irradiation, but it has a TONCO of 35 when immobilized on hexaniobate nanoscrolls. Transient absorption spectroscopy studies reveal that the slow back-electron transfer and the higher reducing power of the hexaniobate conduction-band electrons play a major role for the photocatalytic process. The r...

In this work, a novel complex fac-[Re(CO)3(dcbH2)( trans-stpy)]+, (dcbH2 = 4,4'-dicarboxylic acid-2,2'-bipyridine; trans-stpy = trans-4-styrylpyridine) was synthesized and characterized toward its spectroscopic, photochemical, and photophysical properties. The experimental data provide new insights on the mechanism of photochemical trans-to- cis isomerization of the stilbene-like ligand coordinated to Re(I) polypyridyl complexes. The new complex exhibits an unusual and strong dependence of the isomerization quantum yield (Φt →c) on the irradiation wavelength. Φt →c was 0.81 ± 0.08 for irradiation at 365 nm and continuously decreased as the irradiation wavelength is shifted to the visible. At 405 nm irradiation Φt →c is almost 2 orders of magnitude lower (0.010 ± 0.005) than that observed at 365 nm excitation. This behavior can be explained by the low-lying triplet metal-to-ligand charge-transfer excited state (3MLCT) that hinders the triplet photoreaction mechanism under visible light absorption. Under UV irradiation, direct population of styrylpyridine-centered excited state (1IL) leads to the occurrence of the photoisomerization via a singlet mechanism. Further experiments were performed with the complex immobilized on the surface of TiO2 and Al2O3 films. The nonoccurrence of isomerization at the oxide surfaces even under UV excitation evidences the role of energy gap between the 1IL/1MLCT states on the photochemical/photophysical processes. The results establish important relationships between the molecular structure and the photoelectrochemical behavior, which can further contribute to the development of solid-state molecular switches based on Re(I) polypyridyl complexes.

The search for cost-effective devices for solar energy conversion has driven considerable research efforts from chemists, physicists, and material scientists. In dye-sensitized solar cells (DSSCs), TiO 2 is the most widely employed semiconductor due its availability and outstanding properties. Nevertheless, other metal oxides have been tested in DSSCs, aiming at a deeper understand of the role of morphological and electronic properties on the DSSC photoelectrochemical parameters as well as the possibility to produce composites able to boost the overall conversion efficiency. In this chapter, attention is given to the application of Nb 2 O 5 thin films in DSSCs. Their preparation methods, morphologic, optical, and electronic properties are summarized and an overview of their application with DSSCs is provided. Despite a comprehensive review of the literature, the main aim of this work is to correlate the intrinsic properties of this interesting metal oxide with the photoelectrochemical behavior of DSSCs. Selected examples of application of Nb 2 O 5 as mesoporous or blocking layers in DSSCs are discussed and the main challenges to production of more efficient devices are highlighted.

In this work, a novel complex fac-[Re(CO)

CAPES - Coordenação de Aperfeiçoamento de Pessoal de Nível Superior O presente trabalho descreve as propriedades espectroscópicas, fotofísicas, fotoquímicas e fotoeletroquímicas do complexo fac-[Re(CO)3(dcbH2)(trans-stpy)]+ (dcbH2= ácido 4,4’dicarboxílico-2,2’-bipiridina, trans-stpy = trans-4-estirilpiridina). O composto foi caracterizado por espectroscopia de ressonância magnética nuclear de prótons (1H RMN) e espectroscopia vibracional na região do infravermelho, para elucidar sua estrutura e comprovar sua pureza. Ensaios de espectrofotometria na região do UV-Vis mostram que na região de 390 a 500 nm ocorre uma transferência de carga do metal para o ligante (MLCT) dcbH2 e, na região de 330 a 380 nm, a absorção é dominada por transições centradas no ligante trans-stpy. Tais interpretações são corroboradas por simulações teóricas. São observadas variações espectrais sob irradiação em 405 nm e 365 nm atribuídas à isomerização fotoinduzida trans-cis do ligante coordenado. Os rendimentos quânticos de isomerização () foram determinados por 1H RMN e evidenciam uma dependência do comprimento de onda de irradiação. Enquanto que para irradiação em 405 nm,  = 0,010, para 365 nm,  = 0,81. O comportamento fotoquímico observado foi racionalizado com base na energia relativa dos estados excitados de menor energia. Ambos isômeros apresentam luminescência a 298 K quando excitados na região de sua MLCT. Tanto a espécie trans quanto cis, apresentam o rendimento quântico de emissão de em = 0,001 proveniente da desativação do estado 3MLCT. Os dois isômeros do complexo foram ancorados na superfície de filmes finos de TiO2 e Al2O3 e as propriedades fotoeletroquímicas dos filmes sensibilizados foram investigadas. Em TiO2, ambos isômeros são capazes de gerar fotocorrente quando excitados em 405 nm e 365 nm, sendo que a injeção eletrônica suprime a fotoisomerização trans-cis na superfície do óxido semicondutor. A fotoisomerização não foi observada na superfície do Al2O3, em que a injeção eletrônica não ocorre devido ao potencial mais negativo da banda de condução do óxido. A partir dos dados obtidos foi possível elucidar a participação dos estados excitados em função do comprimento de onda de irradiação e propor os possíveis caminhos de desativação destes estados excitados. The present work describes the spectroscopic, photophysical, photochemical and photoelectrochemical properties of the fac-[Re(CO)3(dcbH2)(trans-stpy)]+ complex (dcbH2 = 4,4'-dicarboxylic acid-2,2'-bipyridine, trans-stpy = trans-4-styrylpyridine). The compound was characterized by proton nuclear magnetic resonance spectroscopy (1H NMR) and infrared spectroscopy to prove its structure and purity. Its absorption spectrum in the UV-Vis region shows a broad absorption band from 390 to 500 nm, ascribed to the metal to the ligand dcbH2 charge transfer transition (MLCT). In the region from 330 to 380 nm, the absorption occurs through trans-stpy internal transitions. These interpretations were corroborated by theoretical simulations. Spectral variations are observed under irradiation in 405 nm and 365 nm and are attributed to the trans-cis photoinduced isomerization of the coordinated stpy ligand. The isomerization quantum yields () were determined by 1H NMR and are wavelength dependent. While for irradiation at 405 nm,  = 0.010, for 365 nm,  = 0.81. The observed photochemical behavior was rationalized based on the relative energy of the lower energy excited states. Both isomers exhibit luminescence at 298 K when excited in the MLCT absorption region , with similar quantum yields em = 0.001. The radiative decay is attributed to the 3MLCT excited state. The two isomers were anchored on the surfaces of TiO2 and Al2O3 thin films and the photoelectrochemical properties of the sensitized films were investigated. In TiO2, both isomers are capable of generating photocurrent when excited at 405 nm and 365 nm and the electron injection quenches the trans-cis photoisomerization on the surface of the metal oxide. The photoisomerization does also not occur on the surface of Al2O3 in which electron injection is not favored due to the more negative potential of the Al2O3 conduction band. From the data obtained it was possible to elucidate the participation of the excited states as a function of the irradiation wavelength and to propose the possible ways to deactivation of these excited states. Dissertação (Mestrado)

CONTEXT: Electrical burns are an important etiology in dealing with patients suffering from burns. In situations of extensive deep lesions of multiple organs and systems affecting young and economically active people, there is a need for expensive multidisciplinary treatment, with a high socioeconomic cost for the community. Among the permanent injuries that explain this high cost, eye injuries stand out, since they are widely disabling. Although rare, lesions of the posterior segment of the eye are associated with higher incidence of major sequelae, and thus deserve special attention for dissemination and discussion of the few cases observed.CASE REPORT: The authors report the case of a patient who suffered high-voltage electrical burns and presented bilateral maculopathy, which evolved with a need for a surgical approach to repair retinal detachment and permanent low visual acuity.CONCLUSION: This report highlights the rarity of the etiology of maculopathy and the need for campaigns for prevention not only of burns in general, but also especially of electrical burns.

Bioprocesses are characterized by the fact that small variations in operating conditions may have a substantial impact on the final batch quality. Therefore, the early detection and isolation of faults allow implementing corrective actions before the effects of deviations from the normal operation have a detrimental effect on production. In this work a new strategy for the statistical monitoring of batch processes is presented, and it is applied to monitor the operation of a fermentation process. The methodology works in the original variable space, therefore it only uses the Hotelling statistic for detection purposes. To determine the set of measurements by which the fault is revealed, the nearest in control neighbor to the observation point is calculated, and the distance between these two points is used to evaluate the contribution of each observation to the inflated statistic. In contrast to the existing latent-variable and original-variable based approaches, a simple hierarchical clustering technique allows to identify the set of suspicious measurements, without assuming the probability density function of the variable contributions. Furthermore, the performance of the proposed identification procedure is compared to the one achieved using other monitoring techniques. A well-known fed-batch fermentation benchmark is employed with this purpose, and the comparison is based on the results of a comprehensive set of simulated fault scenarios. Fil: Cedeño Viteri, Marco Vinicio. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Planta Piloto de Ingeniería Química. Universidad Nacional del Sur. Planta Piloto de Ingeniería Química; Argentina Fil: Rodriguez Aguilar, Leandro Pedro Faustino. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Planta Piloto de Ingeniería Química. Universidad Nacional del Sur. Planta Piloto de Ingeniería Química; Argentina Fil: Sanchez, Mabel Cristina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Planta Piloto de Ingeniería Química. Universidad Nacional del Sur. Planta Piloto de Ingeniería Química; Argentina

Hotelling's statistic, also called T 2-statistic, is widely used in statistical process control as an extension of the univariate student's chart to reliably detect out of control status in multivariate processes. Although it is a very efficient tool for detection purposes, by itself, it offers no assistance about the origin of the declared faulty status. Several different approaches have been proposed to estimate the variable values' effect on the overall statistic's value. Some of these strategies work in the original measurement space, while others interpret the results coming from the analysis in latent variable spaces using for example Principal Component Analysis or Independent Component Analysis. With the same purpose, we present a novel approach, based on finding the nearest in-control neighbor of the observation point, in this work. The distance between both points is used to determine the contribution of each variable to the out of control state. Those variables whose distance measures exceed a certain threshold value are considered as suspicious. The results of the proposed strategy are compared with those obtained using other strategies that work both the original and latent variable spaces for case studies extracted from the literature. Fil: Cedeño Viteri, Marco Vinicio. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Planta Piloto de Ingeniería Química. Universidad Nacional del Sur. Planta Piloto de Ingeniería Química; Argentina Fil: Rodriguez Aguilar, Leandro Pedro Faustino. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Planta Piloto de Ingeniería Química. Universidad Nacional del Sur. Planta Piloto de Ingeniería Química; Argentina Fil: Alvarez Medina, Carlos Rodrigo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Planta Piloto de Ingeniería Química. Universidad Nacional del Sur. Planta Piloto de Ingeniería Química; Argentina Fil: Sanchez, Mabel Cristina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Planta Piloto de Ingeniería Química. Universidad Nacional del Sur. Planta Piloto de Ingeniería Química; Argentina