In this work, we systematically evaluated the potential of using boronic acid functionalized magnetic particles in the capturing of human immunoglobulin G under typical mammalian cell culture conditions. For comparison, Protein A coated magnetic particles were also used. The binding pH was found to significantly influence the adsorption isotherms of boronic acid particles with the higher capacities (0.216 g IgG/g support) being observed at pH 7.4. Comparatively, this value was 0.109 g IgG/g support, for Protein A particles under the same conditions. Both particles revealed very fast adsorption kinetics with more than 70% of the maximum binding capacity being achieved in a few seconds. The effect of glucose and lactate, which are known to interact with boronic acid, was evaluated. For glucose, the binding capacity was significantly influenced by the pH and decreased as pH increased. At pH 9.5, a 70% lower binding capacity was observed for glucose concentrations as low as 0.5 g/l. The effect of lactate was less pronounced and almost pH independent reaching at most 20% decrease in binding capacity. Nevertheless, the effect of both molecules was always lower at pH 7.4. The optimization of the elution conditions enabled complete recovery of bound IgG from boronic acid particles using 50mM Tris-HCl, 200 mM sorbitol, 200 mM NaCl at pH 8.5.

Transactional Memory (TM) is an approach to concurrency control in general pur- pose programming languages that inherits the concept of transaction from the database setting. Unlike other language constructs such as locks, TM has an optimistic approach to concurrency control by allowing more than one thread to access simultaneously the same critical section. A transaction always executes as if it is alone in the system, and in the end its effects are undone (rolled back) if it conflicts with another concurrent transac- tions. In spite of the potential for increasing scalability and performance, TM is a recent and developing programming model and still has a very limited impact in real-world applications.
Designing and developing concurrent software is difficult and error prone. Concur- rent programs exhibit concurrency anomalies that originate faults and failures. Despite some claims that TM programs are less error prone, they still exhibit concurrency anoma- lies such as high-level dataraces, i.e., wrong delimitations of transactions’ scope, and stale-value errors, that occur when the value of a shared variable jumps from an atomic block to another.
Programs with this kind of anomalies can exhibit unpredictable and wrong behaviour, not fulfilling the goals for which they were conceived.
This work aims the detection of anomalies through static analysis of transactional Java ByteCode programs that execute in strong atomicity. A extensible and flexible framework is proposed, which can be extended with plugins that detect specific types of anomalies. With this framework we expect to prove that high-level dataraces and stale-value errors can be detected with reasonable precision through static analysis.

Keywords: Atomicity Violation, High-Level Datarace, Static Analysis, Concurrency, Software Transactional Memory

This paper reports the design, preparation and characterization of cellulose affinity membranes for antibody purification using a new methodology. Cellulose membranes were prepared from polymer-ionic liquid solutions, namely 1-butyl-3-methylimidazolium chloride {([BMIM][Cl])}, by the water induced phase inversion process. After functionalization with a synthetic ligand 2-(3-aminophenol)-6-(4-amino-1-naphthol)-4-chloro-s-triazine (ligand 22/8), these were evaluated as affinity supports for human immunoglobulin G {(IgG).} Membranes were characterized in terms of morphology {(SEM)}, porosity (mercury porosimetry), hydrophilicity (contact angle measurement), transport properties (permeability) and mechanical performance {(DMA).} Membranes prepared with varying cellulose contents (5 and 10&\#xa0;wt.% cellulose in ionic liquid solutions) lead to films with different properties. The 10&\#xa0;wt.% cellulose membrane presented enhanced morphological and mechanical properties, however, the morphology of this membrane was significantly altered after ligand coupling. Adsorption isotherms for human {IgG} onto 10&\#xa0;wt.% matrix activated with ligand 22/8 were obtained. Preliminary results showed that the bovine serum albumin {(BSA)}, a model impurity, did not adsorb onto the membrane while up to 6&\#xa0;mg {IgG/g} was bound and 2&\#xa0;mg {IgG/g} recovered.

There are numerous reports of coumarin ester derivatives, in particular phosphate esters, as photocleavable cages in biological systems. Despite the comprehensive analysis of the photocleavage mechanism, studies of 4-methylcoumarin caged phosphates and/or nucleotides were always performed at constant pH. In this work, we present the study of the pH effect on the photochemistry of (7-diethylaminocoumarin-4-yl)methyl phosphate (DEACM-P). Fluorescence and photocleavage quantum yields, as well as the fluorescence decay times were measured as a function of the pH. It was found that the pH produces significant changes in the overall photochemical quantum yield of DEACM-P, and the observed changes are complementary to those obtained from the fluorescence quantum yield. Deprotonation of DEACM-HPO4 - to yield DEACM-PO4 2-, produces a decrease in the photochemical quantum yield (from 0.0045 to 0.0003) and an increase in the fluorescence quantum yield (from 0.072 to 0.092). Moreover, from the analysis of the decay times, we have also found that hydroxyl ion is not only relevant, but it is mechanistically involved in the photoreaction of DEACM-HPO4 -.

There are numerous reports of coumarin ester derivatives, in particular phosphate esters, as photocleavable cages in biological systems. Despite the comprehensive analysis of the photocleavage mechanism, studies of 4-methylcoumarin caged phosphates and/or nucleotides were always performed at constant pH. In this work. we present the study of the pH effect on the photochemistry of (7-diethylaminocoumarin-4-yl)methyl phosphate (DEACM-P). Fluorescence and photocleavage quantum yields, as well as the fluorescence decay times were measured as a function of the pH. It was found that the pH produces significant changes in the overall photochemical quantum yield of DEACM-P, and the observed changes are complementary to those obtained from the fluorescence quantum yield. Deprotonation of DEACM-HPO(4)(-) to yield DEACM -PO(4)(2-), produces a decrease in the photochemical quantum yield (from 0.0045 to 0.0003) and an increase in the fluorescence quantum yield (from 0.072 to 0.092). Moreover, from the analysis of the decay times, we have also found that hydroxyl ion is not only relevant, but it is mechanistically involved in the photoreaction of DEACM-HPO(4)(-).

The periplasmic sensor domains encoded by genes gsu0582 and gsu0935 are part of methyl accepting chemotaxis proteins in the bacterium Geobacter sulfurreducens (Gs). The sensor domains of these proteins contain a heme-c prosthetic group and a PAS-like fold as revealed by their crystal structures. Biophysical studies of the two domains showed that nitric oxide (NO) binds to the heme in both the ferric and ferrous forms, whereas carbon monoxide (CO) binds only to the reduced form. In order to address these exogenous molecules as possible physiological ligands, binding studies and resonance Raman (RR) spectroscopic characterization of the respective CO and NO adducts were performed in this work. In the absence of exogenous ligands, typical RR frequencies of five-coordinated (5c) high-spin and six-coordinated (6c) low-spin species were observed in the oxidized form. In the reduced state, only frequencies corresponding to the latter were detected. In both sensors, CO binding yields 6c low-spin adducts by replacing the endogenous distal ligand. The binding of NO by the two proteins causes partial disruption of the proximal Fe-His bond, as revealed by the RR fingerprint features of 5cFe-NO and 6cNO-Fe-His species. The measured CO and NO dissociation constants of ferrous GSU0582 and GSU0935 sensors reveal that both proteins have high and similar affinity toward these molecules (Kd ≈ 0.04−0.08 μM). On the contrary, in the ferric form, sensor GSU0582 showed a much higher affinity for NO (Kd ≈ 0.3 μM for GSU0582 versus 17 μM for GSU0935). Molecular dynamics calculations revealed a more open heme pocket in GSU0935, which could account for the different affinities for NO. Taken together, spectroscopic data and MD calculations revealed subtle differences in the binding properties and structural features of formed CO and NO adducts, but also indicated a possibility that a (5c) high-spin/(6c) low-spin redox-linked equilibrium could drive the physiological sensing of Gs cells.

Increasing levels of environmental pollution and destruction of the planet, as
well as the future of societies, have been prominent themes in our time.
Concern about the sustainable future of ecosystems and future generations
brings to each sector of activity the need to define a process of sustainable development
and measures that ought to be implemented.
In the construction sector this is a major issue, since it consumes a great part of
natural resources, and leads to high emissions of pollutants. Likewise, this sector
determines the mode of living of human beings, as well as their comfort and health.
The work herein presented has the purpose to study how, and what systems and
procedures should be implemented to ensure techniques for sustainable construction,
and consequently achieve the principles of sustainable development into its
components: environment, society and economy.
The national reality of professionals will also be referred to, thus contributing to
a practice of sustainable construction, complementary to what currently exists both
national and internationally.
Thus, this study aims to reflect on the importance of certification, systems and
procedures, to ensure compliance of construction with the sustainability goals.

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Previous studies have demonstrated that Geobacter sulfurreducens requires the c-type cytochrome OmcZ, which is present in large (OmcZL; 50-kDa) and small (OmcZS; 30-kDa) forms, for optimal current production in microbial fuel cells. This protein was further characterized to aid in understanding its role in current production. Subcellular-localization studies suggested that OmcZS was the predominant extracellular form of OmcZ. N- and C-terminal amino acid sequence analysis of purified OmcZS and molecular weight measurements indicated that OmcZS is a cleaved product of OmcZL retaining all 8 hemes, including 1 heme with the unusual c-type heme-binding motif CX14CH. The purified OmcZS was remarkably thermally stable (thermal-denaturing temperature, 94.2°C). Redox titration analysis revealed that the midpoint reduction potential of OmcZS is approximately −220 mV (versus the standard hydrogen electrode [SHE]) with nonequivalent heme groups that cover a large reduction potential range (−420 to −60 mV). OmcZS transferred electrons in vitro to a diversity of potential extracellular electron acceptors, such as Fe(III) citrate, U(VI), Cr(VI), Au(III), Mn(IV) oxide, and the humic substance analogue anthraquinone-2,6-disulfonate, but not Fe(III) oxide. The biochemical properties and extracellular localization of OmcZ suggest that it is well suited for promoting electron transfer in current-producing biofilms of G. sulfurreducens.

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Neste trabalho pretende-se estudar a variabilidade da frequência cardíaca através da implementação de vários métodos de análise de electrocardiogramas. Na primeira parte descrevem-se os métodos de análise espectral, bem como a representação tempo-frequência. A decomposição de sinais para detectar e isolar os batimentos cardíacos do electrocardiograma é implementada. Descrevem-se algoritmos de isolamento para detecção dos eventos interessantes e pontos fiduciais que os constituem. Na segunda parte estima-se a variação da frequência cardíaca e estabelece-se a sua relação com as variações temporais e espectrais das características encontradas pelos métodos implementados na primeira parte do trabalho.

2-Styryl-1-benzopyrylium derivatives exhibit deeper hues and absorption spectra that are substantially red-shifted when compared with their 2-phenyl-1-benzopyrylium analogues. They follow the same pH and light-dependent network of chemical reactions previously described for 2-phenyl-1-benzopyrylium compounds. In this work, the photochromic properties of 7-hydroxy-2-(4-hydroxystyryl)-1-benzopyrylium chloride are reported. This compound was fully characterized by UV-vis absorption, fluorescence emission, pH jumps, and flash photolysis, and its properties were compared with the analogue 7,4'-dihydroxyflavylium (7-hydroxy-2-(4-hydroxyphenyl)-1- benzopyrylium). The trans-chalcones of both compounds lacking the hydroxyl in position 2 were synthesized and used as model compounds since they exhibit cis-trans isomerization but cannot be involved in the other processes resulting from the ring closure. The transient absorption of two triplets attributed to the chalcones Ct/Ct(-), and a tautomer was detected by nanosecond flash photolysis, independent of the existence of the 2-hydroxyl substituent. The experimental results are compatible with the main formation of cis-chalcone from the singlet state. In the case of the styryl derivatives, the fraction of triplet formed from excitation of Ct is much higher, and the fraction of isomerization is much smaller. For this reason, the photochemistry of 7-hydroxy-2-(4-hydroxystyryl)-1-benzopyrylium in water is much less efficient than that of its parent 7,4'-dihydroxyflavylium; however, in the presence of CTAB micelles, intense red colors can be obtained upon irradiation, confirming the usefulness of this family of compounds as photochromic systems.

Lactoperoxidase (LPO) is a structurally complex and stable mammalian redox enzyme. Here we aim at evaluating the influence of ionic interactions and how these intertwine with the structural dynamics, stability and activity of LPO. In this respect, we have compared LPO guanidinium hydrochloride (GdmCl) and urea denaturation pathways and performed a detailed investigation on the effects of pH on the LPO conformational dynamics and stability. Our experimental findings using far-UV CD, Trp fluorescence emission and ESR spectroscopies clearly indicate that LPO charged-denaturation with GdmCl induced a sharp two-step process versus a three-step unfolding mechanism induced by urea. This differential effect between GdmCl and urea suggests that ionic interactions must play a rather prominent role in the stabilization of LPO. With both denaturants, the protein core was shown to retain activity up to near the respective Cm values. Moreover, a pH titration of LPO evidenced no significant conformational alterations or perturbation of heme activity within the 4 to 11 pH interval. In contrast, alterations of ionic interactions by poising LPO at pH 3, 2 and 12 resulted in a loss of secondary structure, loosening of tertiary contacts and loss of activity, which appear to be associated with the perturbation of the hydrophobic core, as evidenced by ANS binding, as well as disruption of the heme pocket demonstrated by optical and EPR spectroscopies. Overall, LPO is characterised by a high degree of peripheral structural plasticity without perturbation of the core heme moiety. The possible physiological meaning of such features is discussed.