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Background: Endoscopic ultrasound (EUS) is important for the evaluation of patients with common bile duct (CBD) dilation. Aims: The purpose of this study was to evaluate the diagnostic performance of EUS for CBD dilation in patients with negative initial studies. Methods: This was a retrospective cohort study that included patients who underwent EUS for CBD dilation (≥ 7 mm if intact anatomy or ≥ 10 mm if prior cholecystectomy) in the absence of pathology on previous ultrasonography (US), computed tomography (CT), and/or magnetic resonance cholangiopancreatography (MRCP). Results: A total of 109 patients were included, among whom 41 had a positive EUS: 33 choledocholithiasis (30.3%), 6 chronic pancreatitis (5.5%), and 2 ampullary cancer (1.8%). If the EUS was negative, no pathology was found during 1-year follow-up. Older age was associated with positive EUS (79 versus 71 years, p = 0.030). Patients with jaundice, cholelithiasis, and altered liver biochemistry were 16.2 (p = 0.002), 3.1 (p = 0.024), and 2.9 (p = 0.009) times more likely to have positive EUS, respectively. A total of 53 patients had a negative MRCP (48.6%); those with biliary abdominal pain and jaundice were 15.5 (p < 0.001) and 20.0 (p = 0.007) times more likely to have positive EUS, respectively. Considering asymptomatic patients with normal liver tests, CBD diameter ≥ 10 mm in US and ≥ 11 mm in CT can predict a positive EUS (AUC 0.754, p = 0.047 and AUC 0.734, p = 0.048). Conclusions: EUS is a useful diagnostic method for patients with unexplained CBD dilation, even if negative MRCP, and especially in patients with older age, abdominal pain, jaundice, cholelithiasis, and/or altered liver biochemistry. CBD diameter in US and CT had a moderate discriminative ability in predicting positive EUS in asymptomatic patients without altered liver biochemistry. [ABSTRACT FROM AUTHOR]

This work aimed to define strategies to increase the bioproduction of 6 pentyl-α-pyrone (bioaroma). As first strategy, fermentations were carried out in the solid state, with agro-industrial residues: Mauritia flexuosa Liliopsida. and Manihot esculenta Crantz in isolation, conducting them with different nutrient solutions having Trichoderma harzianum as a fermenting fungus. Physicochemical characterizations, centesimal composition, lignocellulosic and mineral content and antimicrobial activity were required. Fermentations were conducted under different humidification conditions (water, nutrient solution without additives and nutrient solutions with glucose or sucrose) for 9 days. Bioaroma was quantified by gas chromatography, assisted by solid-phase microextraction. The results showed the low production of this compound in fermentations conducted with sweet cassava (around 6 ppm (w/w)). The low bioproduction with sweet cassava residues can probably be related to its starch-rich composition, homogeneous substrate, and low concentration of nutrients. Already using buriti, the absence of aroma production was detected. Probably the presence of silicon and high lignin content in buriti minimized the fungal activity, making it difficult to obtain the aroma of interest. Given the characteristics presented by the waste, a new strategy was chosen: mixing waste in a 1:1 ratio. This fermentation resulted in the production of 156.24 ppm (w/w) of aroma using the nutrient solution added with glucose. This combination, therefore, promoted more favorable environment for the process, possibly due to the presence of fermentable sugars from sweet cassava and fatty acids from the buriti peel, thus proving the possibility of an increase of around 2500% in the bioproduction of coconut aroma. [ABSTRACT FROM AUTHOR]

As the concern towards environmental deterioration grows worldwide, new technological achievements become essential for all countries. Among the technologies with great potential of bioremediation is microencapsulation of active material. Several studies have investigated the use of controlled release of active materials as a way of biostimulation and supplying the nutrients necessary for the bioremediation process. In fact, as the use of microorganisms has a great potential in degrading crude oils, this work aims to use that technology and to associate it to produce controlled-release capsules of nitrogen, phosphorus, and potassium (N, P, and K) for bioremediation purposes. For the capsule formulation, polymers of sodium alginate, Capsul®, and the commercial fertilizer NPK from Sempre Verde Inc. were used. Crude oil was the only carbon source and mineral medium for microorganism growth. Controlled-release nutrient capsules, with 4 mm in diameter, made of 3.0 % alginate ( w/ v) and 4.0 % Capsul® ( w/ v) were produced. Those capsules were used in association with a microbial consortium, in a liquid phase bioremediation process, having degraded 43.6 % of the total hydrocarbon within 240 h, evidencing thus as a promising tool for hydrocarbon bioremediation. [ABSTRACT FROM AUTHOR]

We discuss several adaptive mesh-refinement strategies based on ( h − h/2)-error estimation. This class of adaptive methods is particularly popular in practise since it is problem independent and requires virtually no implementational overhead. We prove that, under the saturation assumption, these adaptive algorithms are convergent. Our framework applies not only to finite element methods, but also yields a first convergence proof for adaptive boundary element schemes. For a finite element model problem, we extend the proposed adaptive scheme and prove convergence even if the saturation assumption fails to hold in general. [ABSTRACT FROM AUTHOR]

The h- h/2-strategy is one well-known technique for the a posteriori error estimation for Galerkin discretizations of energy minimization problems. One considers $${\eta:=\Vert\phi_{h/2}-\phi_h\Vert}$$ to estimate the error $${\Vert\phi-\phi_h\Vert}$$ , where $${\phi_h}$$ is a Galerkin solution with respect to a mesh $${\mathcal{T}_h}$$ and $${\phi_{h/2}}$$ is a Galerkin solution with respect to the mesh $${\mathcal{T}_{h/2}}$$ obtained from a uniform refinement of $${\mathcal{T}_h}$$ . This error estimator is always efficient and observed to be also reliable in practice. However, for boundary element methods, the energy norm is non-local and thus the error estimator η does not provide information for a local mesh-refinement. We consider Symm’s integral equation of the first kind, where the energy space is the negative-order Sobolev space $${\widetilde{H}^{-1/2^{\vphantom{H}}}(\Gamma)}$$ . Recent localization techniques allow to replace the energy norm in this case by some weighted L2-norm. Then, this very basic error estimation strategy is also applicable to steer an h-adaptive algorithm. Numerical experiments in 2D and 3D show that the proposed method works well in practice. A short conclusion is concerned with other integral equations, e.g., the hypersingular case with energy space $${\widetilde{H}^{1/2}(\Gamma)}$$ and $${H^{1/2}_0(\Gamma)}$$ , respectively, or a transmission problem. [ABSTRACT FROM AUTHOR]

The objective of the study was to evaluate the frequency and clinical characteristics of ocular complications and their risk factors, as well as autologous serum tears (AST) for the treatment of dry eye in these patients. Data from the files of 124 patients who had undergone allogeneic haematopoietic progenitor cell transplantation (HPCT) were evaluated. In addition, 33 HPCT patients were examined and their data were compared with controls. Analysis of tears and AST was performed. Dry eye manifestation occurred in 32% of patients and was positively correlated with age over 27 years (P=0.05), peripheral blood progenitor cell transplant (P=0.002), chronic graft-versus-host disease (P=0.0027), and chronic or acute myeloid leukaemia (P=0.001). Dry mouth and Schirmer test <5 mm were predictive factors for dry eye in HPCT patients (P=0.002 and odds ratio 3.9 and P=0.007, odds ratio=5.9, respectively). Microbiological analysis revealed that six of 11 AST samples were contaminated after 30 days of use. The present study supports the role of potential risk factors for ocular complications and key elements to detect alterations in the tear film from HPCT patients. In addition, AST contamination must be considered after longer periods of use.Bone Marrow Transplantation (2006) 38, 223–227. doi:10.1038/sj.bmt.1705426; published online 19 June 2006 [ABSTRACT FROM AUTHOR]

Waste biomass Sargassum sp. biosorbed 100% of Cd2+ and 99.4% of Zn2+ from a 3 and 98 mg l-1 solution (pH 4.5), respectively, at the end of four serial experiments. Of the five desorbents studied in consecutive adsorption/desorption cycles, CaCl2 0.05 M eluted nearly 40% of both metals and decreased the biosorption in only 8% and 17% of Cd2+ and Zn2+, respectively. Although NaOH desorbent improved the heavy metal uptake from the second cycle onwards, it did not elute metals from the pre-loaded biomass. [ABSTRACT FROM AUTHOR]

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Biosorption is becoming an important component in the integrated approach to the treatment of aqueous effluents. The economics of biomass technical applications are improved by using waste biomass instead of purposely-produced biomass. Biomass derived from an alginate extraction industry – Sargassum sp. – was examined for its ability to function as a biosorbent for metals such as cadmium, zinc and copper. For use in column applications, biomass should be immobilized. To the algae reinforcement, the biomass was embedded in polyethleneimine (PEI), followed by glutaraldehyde crosslinking. Equilibrium Zn and Cu isotherms were analysed using the immobilization ratio that showed the best Cd performance. Either Freundlich or Langmuir models can describe the passive biosorption equilibrium of cadmium, zinc and cooper. The preference for this series of metals by the biomass was found to be Cd > Zn > Cu, with maximum uptake values of 157.8, 118.5 and 77.4 mg/g dry weight biomass for Cd, Zn and Cu. respectively. The metal binding capacity by non-living biomass is an important quality for industrial use. [ABSTRACT FROM AUTHOR]