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Secondary ion mass spectrometry (SIMS) depth profiling has been applied to the study of the thermal annealing of ohmic contacts for high electron mobility transistors. The metallic stacks (Ti/Al/Ni/Au) were deposited over the Al0.28Ga0.72N/GaN/sapphire heterostructures and subjected to a rapid thermal annealing (850 °C for 30 s under N2 atmosphere) to improve the contact performance. The surface morphology and the in-depth chemical distribution of the layered contacts were severely modified due to the treatment. These modifications have been analyzed by SIMS depth profiling and scanning electron microscopy–energy-dispersive X-ray microanalysis. The SIMS analysis conditions have been optimized to achieve simultaneously good sensitivity and to avoid ion-induced mixing effects produced by the primary beam sputtering. [ABSTRACT FROM AUTHOR]

Two siblings, from consanguineous parents, developed in their twenties a Parkinsonian syndrome. In the elder, the disease evolved for 13 years and the necropsic study was diagnostic of Hallervorden-Spatz disease. The younger sibling is severely affected after 12 years of the disorder. Several CT and one MR studies done in this patient during the last 4 years have been normal. Ultrastructural studies of the bone marrow histiocytes and blood lymphocytes disclosed peculiar inclusions. Bromocriptine in low doses proved to be a beneficial therapy for this patient. [ABSTRACT FROM AUTHOR]

Feather waste is a major issue from an economic and environmental point of view. Even though there are already routes for the valorisation of feathers into fertilisers and feather meal, these are considered to have low added value. For more attractive applications, for example in agricultural biodegradable plastics, higher and faster degradability in soil is required. To face this challenge alternative approaches to accelerate biodegradation and disintegration processes are needed. In this context, steam explosion appears as an effective technology to modify the structure of feather and improve its soil degradability. In this work, chicken feathers were treated by steam explosion and the effect of treatment on their structure and physico-chemical and thermal properties were evaluated. Finally, the effect of the process conditions on the disintegration and biodegradation in soil of feathers was also investigated, finding an increased degradation in soil of steam explosion treated feathers. These results open up the possibilities of using feather waste as a component for environmentally friendly agricultural bioplastics that can be degraded in-situ in soil.

In this work, shape-customized scaffolds based on waterborne polyurethane-urea (WBPUU) were prepared via the combination of direct ink writing 3D-printing and freeze-drying techniques. To improve the printing performance of the ink and guarantee a good shape fidelity of the scaffold, cellulose nanocrystals (CNC) were added during the synthesis of the WBPUU and some of the printed constructs were immersed in CaCl 2 prior to the freeze-drying process to promote ionic crosslinking between calcium ions and the polyurethane. The results showed that apart from allowing the ink to be successfully printed, obtaining scaffolds with good shape fidelity, the addition of the CNC resulted in a greater homogeneity of the porous structure as well as an increase of the swelling capacity of the scaffolds. Additionally, the CNC has a reinforcement effect in the printed systems, presenting a higher compression modulus as the CNC content increases. In the case of samples crosslinked by calcium ions, a rigid shell was observed by scanning electron microscopy, which resulted in stiffer scaffolds that presented a lower water absorption capacity as well as an enhancement of the thermal stability. These results showed the potential of this type of post-printing process to tune the mechanical properties of the scaffold, thus widening the potential of this type of material.

In order to continue the development of inks valid for cold extrusion 3D printing, waterborne, polyurethane-urea (WBPUU) based inks with cellulose nanofibers (CNF), as a rheological modulator, were prepared by two incorporation methods, ex situ and in situ , in which the CNF were added after and during the synthesis process, respectively. Moreover, in order to improve the affinity of the reinforcement with the matrix, modified CNF was also employed. In the ex situ preparation, interactions between CNFs and water prevail over interactions between CNFs and WBPUU nanoparticles, resulting in strong gel-like structures. On the other hand, in situ addition allows the proximity of WBPUU particles and CNF, favoring interactions between both components and allowing the formation of chemical bonds. The fewer amount of CNF/water interactions present in the in situ formulations translates into weaker gel-like structures, with poorer rheological behavior for inks for 3D printing. Stronger gel-like behavior translated into 3D-printed parts with higher precision. However, the direct interactions present between the cellulose and the polyurethane-urea molecules in the in situ preparations, and more so in materials reinforced with carboxylated CNF, result in stronger mechanical properties of the final 3D parts.

In this work, polycaprolactone-polyethylene glycol (PCL-PEG) based waterborne polyurethane-urea (WBPUU) inks have been developed for an extrusion-based 3D printing technology. The WBPUU, synthesized from an optimized ratio of hydrophobic polycaprolactone diol and hydrophilic polyethylene glycol (0.2:0.8) in the soft segment, is able to form a physical gel at low solid contents. WBPUU inks with different solid contents have been synthesized. The rheology of the prepared systems was studied and the WBPUUs were subsequently used in the printing of different pieces to demonstrate the relationship between their rheological properties and their printing viability, establishing an optimal window of compositions for the developed WBPUU based inks. The results showed that the increase in solid content results in more structured inks, presenting a higher storage modulus as well as lower tan δ values, allowing for the improvement of the ink's shape fidelity. However, an increase in solid content also leads to an increase in the yield point and viscosity, leading to printability limitations. From among all printable systems, the WBPUU with a solid content of 32 wt% is proposed to be the more suitable ink for a successful printing performance, presenting both adequate printability and good shape fidelity, which leads to the realization of a recognizable and accurate 3D construct and an understanding of its relationship with rheological parameters.

3D printing has exponentially grown in popularity due to the personalization of each printed part it offers, making it extremely beneficial for the very demanding biomedical industry. This technique has been extensively developed and optimized and the advances that now reside in the development of new materials suitable for 3D printing, which may open the door to new applications. Fused deposition modeling (FDM) is the most commonly used 3D printing technique. However, filaments suitable for FDM must meet certain criteria for a successful printing process and thus the optimization of their properties in often necessary. The aim of this work was to prepare a flexible and printable polyurethane filament parting from a biocompatible waterborne polyurethane, which shows potential for biomedical applications. In order to improve filament properties and printability, cellulose nanofibers and graphene were employed to prepare polyurethane based nanocomposites. Prepared nanocomposite filaments showed altered properties which directly impacted their printability. Graphene containing nanocomposites presented sound enough thermal and mechanical properties for a good printing process. Moreover, these filaments were employed in FDM to obtained 3D printed parts, which showed good shape fidelity. Properties exhibited by polyurethane and graphene filaments show potential to be used in biomedical applications.

Optimization of a multivariate calibration process has been undertaken for a Visible-Near Infrared (400-1100nm) sensor system, applied in the monitoring of the fermentation process of the cider produced in the Basque Country (Spain). The main parameters that were monitored included alcoholic proof, l-lactic acid content, glucose+fructose and acetic acid content. The multivariate calibration was carried out using a combination of different variable selection techniques and the most suitable pre-processing strategies were selected based on the spectra characteristics obtained by the sensor system. The variable selection techniques studied in this work include Martens Uncertainty test, interval Partial Least Square Regression (iPLS) and Genetic Algorithm (GA). This procedure arises from the need to improve the calibration models prediction ability for cider monitoring., (Copyright © 2016 Elsevier Ltd. All rights reserved.)

Objective: To compare the prevalence of the main comorbidities in 2 large cohorts of patients with primary Sjögren's syndrome (SS) and systemic lupus erythematosus (SLE), with a focus on cardiovascular (CV) diseases., Methods: This was a cross-sectional multicenter study where the prevalence of more relevant comorbidities in 2 cohorts was compared. Patients under followup from SJOGRENSER (Spanish Rheumatology Society Registry of Primary SS) and RELESSER (Spanish Rheumatology Society Registry of SLE), and who fulfilled the 2002 American-European Consensus Group and 1997 American College of Rheumatology classification criteria, respectively, were included. A binomial logistic regression analysis was carried out to explore potential differences, making general adjustments for age, sex, and disease duration and specific adjustments for each variable, including CV risk factors and treatments, when appropriate., Results: A total of 437 primary SS patients (95% female) and 2,926 SLE patients (89% female) were included. The mean age was 58.6 years (interquartile range [IQR] 50.0-69.9 years) for primary SS patients and 45.1 years (IQR 36.4-56.3 years) for SLE patients (P < 0.001), and disease duration was 10.4 years (IQR 6.0-16.7 years) and 13.0 years (IQR 7.45-19.76 years), respectively (P < 0.001). Smoking, dyslipidemia, and arterial hypertension were associated less frequently with primary SS (odds ratio [OR] 0.36 [95% confidence interval (95% CI) 0.28-0.48], 0.74 [95% CI 0.58-0.94], and 0.50 [95% CI 0.38-0.66], respectively) as were life-threatening CV events (i.e., stroke or myocardial infarction; OR 0.57 [95% CI 0.35-0.92]). Conversely, lymphoma was associated more frequently with primary SS (OR 4.41 [95% CI 1.35-14.43]). The prevalence of severe infection was lower in primary SS than in SLE (10.1% versus 16.9%; OR 0.54 [95% CI 0.39-0.76]; P < 0.001)., Conclusion: Primary SS patients have a consistently less serious CV comorbidity burden and a lower prevalence of severe infection than those with SLE. In contrast, their risk of lymphoma is greater., (© 2016, American College of Rheumatology.)

Myofibroblastoma of the breast is a rare, benign mesenchymal tumor derived from the stroma and tends to occur mainly in middle-aged to elderly men. There are a few cases reported in the literature describing its cytological features. We report the cytological and histological findings of a breast myofibroblastoma in a 68-year-old man. He presented with a palpable nodule of 2-months duration in his left breast. The cytological smears obtained by fine needle aspiration showed less cohesive cellularity in a fascicular arrangement consisting of spindle cells with elongated cytoplasm, occasional nuclear grooves, and intranuclear cytoplasmic inclusions associated to fragments of stromal collagen. The cytological diagnosis was a mesenchymal proliferation suggesting the possibility of myofibroblastoma which was confirmed on histopathological examination. The breast myofibroblastoma has distinctive cytological features that in conjunction with the clinical and radiological data allow a specific diagnosis., (Copyright © 2011 Wiley Periodicals, Inc.)

We report the collection of Aedes aegypti, Culex quinquefasciatus, Cx. interrogator, Cx. thriambus, Cx. coronator, and Cx. salinarius larvae from storm sewers within an endemic area for dengue transmission in Merida, Mexico, during the rainy season of 2011. This is the first record of the dengue vector Ae. aegypti breeding in storm sewers in the southeast of Mexico.

The open abdomen is an ongoing challenge for professionals engaged in its treatment. The change in the integrity of the abdominal wall, the loss of fluids, heat and proteins and contamination of the wound are the main problems. The objective of this article is to describe our experience using the abdominal dressing vacuum-assisted closure therapy in treatment of the open abdomen. Since December 2006, all patients requiring treatment with the open abdomen technique have been treated with the abdominal dressing system and vacuum-assisted closure therapy (VAC(®) KCI, San Antonio, USA). The results obtained with this technique in non traumatic patients are analysed herein. The abdominal dressing system was used on 46 patients in the period between January 2006 and December 2009, with a mean 63 years old (29-80), with a gender distribution of 33 men (72%) and 13 women (28%). Closure of the abdominal wall was possible in 24 patients, 5 of which were primary in the recent postoperative phase, 5 had primary suture of the fascia and application of the supra-aponeurotic prosthesis and 14 had closure of the abdominal wall with a composite polytetrafluoroethylene (PTFE) and polypropylene mesh. Second intention closure took place in the remaining 22 patients (48%), as their conditions did not allow primary closure. The mean treatment time with abdominal dressing was 26 days (6-92) with an average of eight changes per patient. The abdominal dressing topical negative pressure system is a useful option for consideration in the event of needing to leaves the abdomen open. It stabilises the abdominal wall and quantifies and collects exudate from the wound, protects the intra-abdominal viscera and keeps the fascia intact and the cutaneous plane for subsequent closure of the wall., (© 2011 The Authors. © 2011 Blackwell Publishing Ltd and Medicalhelplines.com Inc.)

There is an acknowledged need for shaping 3-D scaffolds with adequate porosity and mechanical properties for biomedical applications. The mechanical properties under static and cyclic compressive testing of dense and designed porous architecture bioceramic scaffolds based on the biphasic calcium phosphate (BCP) systems and BCP-agarose systems have been evaluated. The dense and designed porous architecture scaffolds in BCP systems exhibited a brittle behaviour. Agarose, a biocompatible and biodegradable hydrogel, has been used to shape designed architecture ceramic-agarose scaffolds following a low-temperature shaping method. Agarose conferred toughness, ductility and a rubbery consistency for strains of up to 60% of in ceramic BCP-agarose systems. This combination of ceramic and organic matrix helps to avoid the inherent brittleness of the bioceramic and enhances the compression resistance of hydrogel. The presence of mechanical hysteresis, permanent deformation after the first cycle and recovery of the master monotonous curve indicate a Mullins-like effect such as that observed in carbon-filled rubber systems. We report this type of mechanical behaviour, the Mullins effect, for the first time in bioceramics and bioceramic-agarose systems., (Copyright © 2010 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.)