Pyrene-p-tert-butylcalixarenes inclusion complexes formation: a surface photochemistry study

Diffuse reflectance and luminescence techniques were used to study the photophysics and photochemistry of pyrene within p-tert-butylcalix[n]arenes with n = 4, 6, and 8, and to study their ability to form inclusion complexes in heterogeneous media. Evidences for inclusion complex formation were found for the three hosts under study. Ground state diffuse reflectance results have shown the formation of ground state dimers of pyrene inside the cavity of calix[ 6] arene and calix[ 8] arene, with this feature much more evident for calix[ 6] arene. For calix[ 4] arene, only a monomer fits inside the cavity and the presence of pyrene microcrystals outside the cavity was detected. A luminescence lifetime distribution analysis was performed, revealing the presence of prompt emissions from the pyrene microcrystals outside the cavity in the case of calix[ 4] arene and from the constrained dimers inside the cavities of calix[ 6] arene and calix[ 8] arene. Transient absorption results have shown the presence of pyrene radical cation and also of trapped electrons for the three hosts under study. The formation of the phenoxyl radical of the calixarene following the laser pulsed excitation of pyrene at 355 nm is increased for calix[ 6] arene and calix[ 8] arene. This feature is particularly relevant for calix[ 6] arene, suggesting a very favourable situation for the hydrogen atom abstraction to occur. The analysis of the degradation products revealed the presence of hydroxypyrene as a major photodegradation product for the three hosts. Dihydro-hydroxypyrene was also formed in the case of calix[ 6] arene and calix[ 8] arene. The formation of the calixarene's phenoxyl radical and subsequent hydrogen abstraction is consistent with the formation of dihydro-dihydroxypyrene

Tinctorial behavior of curaua and banana fibers and dyeing wastewater treatment by porous alumina membranes

Physicochemical and dyeing properties using reactive dyes of curaua and banana fibers were studied by means of color strength (K/S), differential scanning calorimetry (DSC), scanning electron microscopy (SEM), and Fourier transform infrared (FTIR) spectroscopy analyses. SEM analysis of alkali-treated fibers showed an increase in roughness due to surface lignin and hemicellulose defibrillation. DSC analysis showed for all the samples an endothermic and an exothermic peak at 70–80 and 340–360 ̊C due to the loss of adsorbed/ absorbed water and to decomposition of α-cellulose, respectively. Alkali-treated fibers dis- played a second peak around 290 ̊C attributed to the degradation of hemicellulose. FTIR spectra of the studied fibers show similar bands with different intensities attributed to the main components of cellulose-based materials. Alkali-pretreated fibers demonstrated excel- lent dyeing ability for all the tested dyes. Dye absorption depends on the chemical fiber, dye structure, and concentration. The results of washing fastness are very good for all the tested fibers. The dyeing effluent treated with an advanced microfiltration method using an improved alumina ceramic membrane shows an average efficiency of 98% in turbidity and color reduction. Low-cost ceramic alumina microfiltration membranes are a very promising advanced treatment for textile industrial effluents allowing water reuse.C2011-UMINHO-2C2T-01 acknowledges the funding from Programa Compromisso para a Ciência 2008, Portugal

Fish Size Correlates to Size and Morphology of Intermuscular Bones in Tambaqui Colossoma macropomum as Shown by Dissection and X-ray Imaging Methods

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The Effect of Aluminium Surface Treatments on the Bonding Properties of Silica-Modified Epoxy Adhesive Joints: A Statistical Approach

A full factorial design is carried out to investigate the effects of different surface treatments, the inclusion of silica microparticles and the use of wash primer on the apparent shear strength and adherent strength of single-lap aluminium joints. Scanning electron microscopy, surface energy and roughness measurements are performed to characterise the aluminium surface. The results show that the use of wash primer decreases the apparent shear strength of the joints significantly. The cohesive failure of the primer is the main cause of the reduction in strength. On the other hand, the inclusion of 10 wt.% of silica microparticles in the adhesive layers increases the shear strength by 26%. Surfaces treated with NaOH for one minute, without using a wash primer, result in the most resistant joint. In contrast to the apparent shear strength, adherent strength is most effective when only degreasing is considered

Tissue Localization and Extracellular Matrix Degradation by PI, PII and PIII Snake Venom Metalloproteinases: Clues on the Mechanisms of Venom-Induced Hemorrhage

20 páginas, 4 figuras, 3 tablas y 7 tablas en material suplementario.Snake venom hemorrhagic metalloproteinases (SVMPs) of the PI, PII and PIII classes were compared in terms of tissue localization and their ability to hydrolyze basement membrane components in vivo, as well as by a proteomics analysis of exudates collected in tissue injected with these enzymes. Immunohistochemical analyses of co-localization of these SVMPs with type IV collagen revealed that PII and PIII enzymes co-localized with type IV collagen in capillaries, arterioles and post-capillary venules to a higher extent than PI SVMP, which showed a more widespread distribution in the tissue. The patterns of hydrolysis by these three SVMPs of laminin, type VI collagen and nidogen in vivo greatly differ, whereas the three enzymes showed a similar pattern of degradation of type IV collagen, supporting the concept that hydrolysis of this component is critical for the destabilization of microvessel structure leading to hemorrhage. Proteomic analysis of wound exudate revealed similarities and differences between the action of the three SVMPs. Higher extent of proteolysis was observed for the PI enzyme regarding several extracellular matrix components and fibrinogen, whereas exudates from mice injected with PII and PIII SVMPs had higher amounts of some intracellular proteins. Our results provide novel clues for understanding the mechanisms by which SVMPs induce damage to the microvasculature and generate hemorrhage.This work was performed in partial fulfillment of the requirements for the PhD degree for Cristina Herrera at Universidad de Costa Rica.Peer reviewe

Can health care providers recognise a fibromyalgia personality?

OBJECTIVES: To determine if experienced health care providers (HCPs) can recognise patients with fibromyalgia (FM) based on a limited set of personality items, exploring the existence of a FM personality. METHODS: From the 240-item NEO-PI-R personality questionnaire, 8 HCPs from two different countries each selected 20 items they considered most discriminative of FM personality. Then, evaluating the scores on these items of 129 female patients with FM and 127 female controls, each HCP rated the probability of FM for each individual on a 0-10 scale. Personality characteristics (domains and facets) of selected items were determined. Scores of patients with FM and controls on the eight 20-item sets, and HCPs’ estimates of each individual’s probability of FM were analysed for their discriminative value. RESULTS: The eight 20-item sets discriminated for FM, with areas under the receiver operating characteristic curve ranging from 0.71-0.81. The estimated probabilities for FM showed, in general, percentages of correct classifications above 50%, with rising correct percentages for higher estimated probabilities. The most often chosen and discriminatory items were predominantly of the domain neuroticism (all with higher scores in FM), followed by some items of the facet trust (lower scores in FM). CONCLUSIONS: HCPs can, based on a limited set of items from a personality questionnaire, distinguish patients with FM from controls with a statistically significant probability. The HCPs’ expectation that personality in FM patients is associated with higher levels for aspects of neuroticism (proneness to psychological distress) and lower scores for aspects of trust, proved to be correct.info:eu-repo/semantics/publishedVersio

The Benefits of Physical Activity on Climacteric Women

As the population ages, there is a need of developing ways to prevent or revert the deleterious effects of aging, especially in climacteric women who suffer with the problems caused by hormonal changes. Exercise is a nonmedicated intervention that can be applied on that population. The benefits of physical activity can positively change body composition, increase levels of muscular strength, balance, and functional capacity. Strength training, aerobic exercise, whole body vibration, and aquatic exercises are some of the modalities that health professionals can prescript to these individuals. Although there are many studies about these exercises, a technique called blood flow restriction is emerging as an alternative to high load exercises but with the same benefits

Tratamento de efluente da indústria de laticínios aplicando processo oxidativo avançado (H2O2/TiO2/UV)

O soro do leite, um subproduto da fabricação de queijos, apresenta altas cargas de lipídios, carboidratos e proteínas, que são de difícil biodegradabilidade e apresentam riscos ao meio ambiente. São produzidos cerca de 145 milhões de toneladas por ano de soro no mundo. Por isso, devem ser tratados adequadamente antes de serem lançados nos corpos receptores. Os processos oxidativos avançados (POA’s) podem ser uma alternativa não convencional, para o tratamento desse tipo de efluente, cuja eficiência do tratamento, tem-se mostrado como uma alternativa viável. Os POA’s são processos físico-químicos que geram espécies transitórias com elevado poder oxidante, principalmente o radical hidroxila (•OH), este radical oxida uma grande variedade de compostos orgânicos em CO2, H2O e íons inorgânicos. Com base nisso, o objetivo do trabalho foi de estudar o tratamento de efluente da indústria de laticínios através de POA’s em reator tubular com lâmpada de luz negra em processo de fotocatálise heterogênea (H2O2/TiO2/UV). Para isso foi utilizado um planejamento experimental 22. Obteve-se melhor resposta na concentração de TiO2 de 1,5 g/L e 200 mM de H2O2, reduzindo-se em cerca de 34% em DQO do efluente, em 20 minutos. Obteve-se um valor final de custo igual a US $0,05/L ou US$ 50/m