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Microneedle‐based electrodes have attracted significant attention due to their potential applications in high‐quality, long‐term electrophysiological monitoring. In this study, micromoulding technology is used to develop a flexible, conductive fabric microneedle (CF–MN) electrode by bonding a conductive textile to polymeric microneedle arrays. The resulting electrode conforms to the curved surfaces of the body, and the use of a conductive textile backing reduces metallization time and costs by 50% over double‐sided dry electrodes. The electrode‐skin impedance of the CF–MN electrodes is significantly lower than that of gel electrodes over a wide frequency range, and tests on healthy volunteers, both at rest and under a range of ambulatory conditions, showed that the electrodes are capable of acquiring electrocardiography (ECG) and electromyography (EMG) signals that have a comparable kurtosis and signal‐to‐noise ratio to those recorded using conventional electrodes, but without the need for skin preparation or the use of a wet gel. The biomechanical properties of the electrode are also characterized. This is the first demonstration of CF–MN electrodes that can ultimately be integrated into clothing, which in turn can facilitate personalized cardiac health management by enabling continuous, long‐term ECG/EMG monitoring during daily activities. [ABSTRACT FROM AUTHOR]

Objective: It is urgent to diagnose giant cell arteritis (GCA) as quickly as possible to prevent irreversible blindness. The traditional gold standard for diagnosing GCA is temporal artery biopsy (TAB). However, TAB lacks diagnostic performance and carries out risks of surgical intervention. The noninvasive color Doppler ultrasound (CDU) seems to be a promising alternative. This study is designed to assess the diagnostic value of CDU in daily clinical practice. Methods: In this prospective cohort study, patients with a clinical suspicion of active GCA were included and underwent a CDU of the temporal arteries. If deemed necessary by the referrer, a TAB and/or 18F‐fluorodeoxyglucose positron emission tomography with computed tomography was performed. The retrospective clinical diagnosis was determined 1 year after inclusion by two physicians experienced in the field of vasculitis. Results: 242 patients were included and GCA was diagnosed in 73 (30%) patients by the defined retrospective clinical diagnosis. Compared with the retrospective diagnosis, CDU has a sensitivity of 60% (48–72), specificity of 94% (89–97), positive predictive value (PPV) of 81% (70–89), negative predictive value (NPV) of 85% (80–88), and an accuracy of 84% (78–88). A total of 84 (35%) patients underwent TAB. TAB has a sensitivity of 66% (51–79), specificity of 100% (90–100), PPV of 100% (100), NPV of 67% (58–75), and an accuracy of 80% (70–88). Conclusion: This study shows comparable diagnostic performance for CDU and TAB and even better CDU results with a bilateral halo present. Considering the advantages of the noninvasive CDU, it is the diagnostic tool of choice. [ABSTRACT FROM AUTHOR]

Hyperhomocysteinemia is a risk factor for cardiovascular disease and occurs frequently in end-stage renal disease (ESRD), but its pathogenesis is poorly understood. We aimed to evaluate one-carbon flux rates of methionine and homocysteine (Hcy) in ESRD patients and healthy controls. Transmethylation (TM), remethylation (RAM), and transsulfuration (TS), as well as Hcy clearance by TS (i.e., TS/plasma total Hcy concentration) and by RM (i.e., RM/plasma total Hcy concentration) were evaluated in relation to body composition, vitamins, and S-adenosylhomocysteine (AdoHcy) and S-adenosylmethionine (AdoMet) levels. After a fixed protein diet for 3 days, primed-continuous infusion of [[sup.2][H.sub.3]methyl-1-[sup.13]C]methionine was performed in the postabsorptive state in 12 hemodialysis patients and 16 healthy volunteers. Hcy clearance by TS (-80%, P < 0.001) and by RM (-77%, P < 0.001) in ESRD patients was decreased compared with healthy controls. The absolute flux rates of TM (-27%, P < 0.01) and RM (-28%, P = 0.02) were lower in the ESRD patients. After adjustment for age, TS was not significantly reduced. Whole blood AdoHcy was significantly elevated in ESRD and was a significant determinant of TM (standardized [beta] = - 1.24, P - 0.01) and RM (standardized [beta] = - 1.43, P = 0.03). In conclusion, patients with ESRD have impaired Hey clearance by TS and RM. Elevated whole blood AdoHcy levels are associated with impaired RM and TM flux rates in these patients, and AdoHcy may be a key regulatory compound in one-carbon flux. stable isotopes; S-adenosylmethionine; transsulfuration; remethylation; transmethylation

Highlights • Novel bandwidth widening concept validated using sloshing liquid metal mass. • Increased bandwidth achieved using a liquid metal filled mass. • Bandwidth widening dependent on acceleration due to oxide skin on liquid metal. • Liquid metal damping effects show enhanced performance. Abstract Linear vibrational energy harvesting devices typically have narrow bandwidths, which limits their practical use, because the resonant frequency needs to match the frequency of the vibration source in order to maximize power generated. This paper presents a method of widening the bandwidth by using a highly dense liquid metal filled mass, which creates a sloshing effect that changes the center of gravity of the cantilever device during motion. The shift in center of gravity causes the resonant frequency of the cantilever to change. Since the resonant frequency of the device is constantly changing during oscillation of the cantilever, this results in a widening of the bandwidth. The displacement of the dense liquid metal has more influence on the center of gravity compared to other less dense liquids thus increasing the bandwidth. The paper demonstrates a 6.5× increase in bandwidth for the liquid metal filled mass compared to a typical air-filled mass with only a 9.6% reduction in power at 1 g acceleration. Acceleration effects and mechanical damping were also investigated and presented within the paper. [ABSTRACT FROM AUTHOR]

The purpose of this study was to investigate the psychometric characteristics (content validity, internal consistency, and subscale structure) of the Hematology Information Needs Questionnaire-62 (HINQ-62), a patient reported outcome measure (PROM) for assessing the need for information among patients with hematological malignancies (HM-patients). Baseline data were used from a prospective study on the need for information which 336 newly diagnosed HM-patients had completed. In phase 1 (design phase), data from the first 135 patients were used and in phase 2 (validation phase), data from the remaining 201 HM patients were used. Content validity was analyzed by examining irrelevance of items. Items were considered irrelevant if more than 10% of the patients scored totally disagree on that item. The subscale structure of the HINQ-62 was investigated with Factor analysis (FA) (exploratory FA in phase 1 and confirmatory FA in phase 2). Cronbach’s α was computed for the different subscales and >.70 was considered as good internal consistency. None of the 62 HINQ-items were irrelevant. Exploratory FA identified five subscales: “Disease, symptoms, treatment and side-effects”, “Etiology, sleep and physical changes”, “Self-care”, “Medical tests and prognosis”, and “Psychosocial”. Root Mean Square Error of Approximation (RMSEA) among patients was 0.037 in phase 1 and 0.045 in phase 2. The comparative fit index (CFI)/Tucker-Lewis index -non-normed fit index among patients was 0.984/0.983 and 0.948/0.946, in phase 1 and 2 respectively. The internal consistency of the subscales was good, with Cronbach’s α 0.82–0.99. The HINQ is a valid PROM for assessing the need for information among Dutch HM-patients at diagnosis. [ABSTRACT FROM AUTHOR]

Lung transplantation is a necessary step for the patients with the end stage of chronic obstructive pulmonary disease. The use of artificial lungs is a promising alternative to natural lung transplantation which is complicated and is restricted by low organ donations. For successful lung engineering, it is important to choose the correct combination of specific biological cells and a synthetic carrier polymer. The focus of this study was to investigate the interactions of human lung epithelial cell line NCl-H292 that is involved in lung tissue development with the biodegradable poly(ε-caprolactone) before and after its chemical modification to evaluate potential for use in artificial lung formation. Also, the effect of polymer chemical modification on its mechanical and surface properties has been investigated. The poly(ε-caprolactone) surface was modified using aminolysis followed by immobilization of gelatin. The unmodified and modified polymer surfaces were characterized for roughness, tensile strength, and NCl-H292 metabolic cell activity. The results showed for the first time the possibility for NCI-H292 cells to adhere on this polymeric material. The resazurin assay showed that the metabolic activity at 24 h postseeding of 80% in the presence of the unmodified and greater than 100% in the presence of the modified polymer was observed. The roughness of the poly(ε-caprolactone) increased from 4 to 26 nm and the film strength increased from 0.01 to 0.045 kN when the material was chemically modified. The results obtained to date show potential for using modified poly(ε-caprolactone) as a scaffold for lung tissue engineering. [ABSTRACT FROM PUBLISHER]

Parylene is commonly used as thin film polymer for MEMS devices and smart materials. This paper investigates the impact on bulk properties due to annealing various types of Parylene films. A thin film of Parylene N, C and a hybrid material consisting of Parylene N and C were deposited using a standard Gorham process. The thin film samples were annealed at varying temperatures from room temperature up to 300 °C. The films were analyzed to determine the mechanical and crystallinity effects due to different annealing temperatures. The results demonstrate that the percentage of crystallinity and the full-width-half-maximum value on the 2θ X-ray diffraction scan increases as the annealing temperature increases until the melting temperature of the Parylene films was achieved. Highly crystalline films of 85% and 92% crystallinity were achieved for Parylene C and N respectively. Investigation of the hybrid film showed that the individual Parylene films behave independently to each other, and the crystallinity of one film had no significant impact to the other film. Mechanical testing showed that the elastic modulus and yield strength increase as a function of annealing, whereas the elongation-to-break parameter decreases. The change in elastic modulus was more significant for Parylene C than Parylene N and this is attributed to the larger change in crystallinity that was observed. Parylene C had a 112% increase in crystallinity compared to a 61% increase for Parylene N, because the original Parylene N material was more crystalline than Parylene C so the change of crystallinity was greater for Parylene C. [ABSTRACT FROM AUTHOR]

ABSTRACT Typically, electroresponsive hydrogels have either a high electrical conductivity with little swelling or large swelling with low conductivity. This paper investigates a method of maintaining high swelling capabilities and increasing electrical conductivity by infusing multiwalled carbon nanotubes (MWCNTs) into a hydrolyzed polyacrylamide hydrogel. Various concentrations of MWCNT and Nafion solutions infused into the hydrogel were investigated. Optical microscopy analysis showed aggregates of carbon nanotube bundles at the macroscale, whereas electron microscopy revealed homogeneous dispersion of carbon nanotube in the polymer matrix at the microscale. Electrical conductivity measurements demonstrated an increase from 0.02 to 0.11 mS cm-1 with infused MWCNT. The MWCNT-infused hydrogels demonstrated a 400% increase in deswelling capabilities during an applied electrical stimulus compared to a noninfused hydrogel. In conclusion, infusing the MWCNT into the hydrogel increased its electrical conductivity, which allows the hydrogel to deswell more rapidly with an applied electrical bias without compromising its mechanical or swelling properties. [ABSTRACT FROM AUTHOR]

For patients with haematological malignancies, information on disease, prognosis, treatment and impact on quality of life is of the utmost importance. To gain insight into the perceived need for information in relation to sociodemographic and clinical parameters, comorbidity, quality of life (QoL) and information satisfaction, we compiled a questionnaire based on existing validated questionnaires. A total of 458 patients diagnosed with a haematological malignancy participated. The perceived need for information was moderate to high (40-70%). Multivariate regression analyses showed that a higher need for information was related to younger age, worse QoL, being member of a patient society and moderate comorbidity. The need for disease and treatment-related information was higher than the need for psychosocial information. A higher need for disease and treatment-related information was associated to being diagnosed with multiple myeloma. A higher need for psychosocial information was related to a lower educational level. The information provision could be improved according to 41% of the patients. Higher satisfaction with provided information was associated with better QoL. Most patients (62%) reported that they wanted to be fully informed about their illness and actively involved in treatment decision-making. The results contribute to improving patient-tailored information provision and shared decision-making in clinical practice. Copyright © 2014 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

ABSTRACT Electro-responsive hydrogels (ERH) are highly researched materials for biomedical applications. However, most of the research is concentrated on the synthesis of novel hydrogels for various applications, and little effort has been made to investigate electrode configuration and optimization of electrical stimulation parameters. This article used a three-dimensional interdigitated (IDT) electrode configuration device to investigate the optimization of electrical actuation parameters in order to radially deswell an ERH. A Pluronic-bismethacrylate hydrogel modified with hydrolyzed methacrylic acid was used as the ERH material. This article reports on using novel electro-actuation parameters and electrode configurations to maximize radial deswelling of an ERH for biomedical applications. The optimal waveform was assessed for, varying electrode spacing's, voltages, duty cycles, and frequencies. The results show that a maximum deswelling occurred with a DC pulsed monophasic waveform, with IDT electrodes spaced close enough to create a relatively uniform electric field, with a peak voltage of 5 V at 1 kHz, and 50% duty cycle. This resulted in a deswelling of 320% in Krebs solution. Electrochemical impedance spectroscopy results show that the impedance is dependent on the ionic concentration of the fluid environment and that the impedance decreases with increasing frequency. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015, 132, 41687. [ABSTRACT FROM AUTHOR]

Smart hydrogels for biomedical applications are highly researched materials. However, integrating them into a device for implantation is difficult. This paper investigates an integrated delivery device designed to deliver an electro-responsive hydrogel to a target location inside a blood vessel with the purpose of creating an occlusion. The paper describes the synthesis and characterization of a Pluronic/methacrylic acid sodium salt electro-responsive hydrogel. Application of an electrical bias decelerates the expansion of the hydrogel. An integrated delivery system was manufactured to deliver the hydrogel to the target location in the body. Ex vivo and in vivo experiments in the carotid artery of sheep were used to validate the concept. The hydrogel was able to completely occlude the blood vessel reducing the blood flow from 245 to 0 ml/min after implantation. Ex vivo experiments showed that the hydrogel was able to withstand physiological blood pressures of > 270 mm·Hg without dislodgement. The results showed that the electro-responsive hydrogel used in this paper can be used to create a long-term occlusion in a blood vessel without any apparent side effects. The delivery system developed is a promising device for the delivery of electro-responsive hydrogels. [ABSTRACT FROM PUBLISHER]

ABSTRACT Stimuli-responsive hydrogels are continuing to increase in demand in biomedical applications. Occluding a blood vessel is one possible application which is ideal for a hydrogel because of their ability to expand in a fluid environment. However, typically stimuli-responsive hydrogels focus on bending instead of radial uniform expansion, which is required for an occlusion application. This article focuses on using an interdigitated electrode device to stimulate an electro-responsive hydrogel in order to demonstrate a uniform swelling/deswelling of the hydrogel. A Pluronic-bismethacrylate (PF127-BMA) hydrogel modified with hydrolyzed methacrylic acid, in order to make it electrically responsive, is used in this article. An interdigitated electrode device was manufactured containing Platinum electrodes. The results in this paper show that the electrically biased hydrogels deswelled 230% more than the non-biased samples on average. The hydrogels deswelled uniformly and showed no visual deformations due to the electrical bias. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part B: Polym. Phys. 2013, 51, 1523-1528 [ABSTRACT FROM AUTHOR]

Wide-bandgap materials such as silicon carbide enable power electronics to face increasing demands for greater power density and high-temperature capability at the chip level. However, new packaging solutions have yet to be found to replace Pb solders in high-temperature applications. In this paper, the applicability of electrodeposited Ag thin film as a novel high-temperature die-attach material to connect power chips to direct-bonded copper substrates is investigated. Ag films were obtained by electrochemical deposition on the backmetallization of Si chips. The joint was then produced by thermocompression bonding at 350^\circC with a 40-N force applied for 10 min in air. A die shear strength of 1.70 MPa (twice the MIL standard) was achieved. The assembly demonstrated satisfactory resistance to thermomechanical fatigue when subjected to thermal aging and thermal cycling tests in high-temperature environments. The proposed bonding technology is thus a suitable solution for the provision of strong and reliable joints for power devices which have to operate in extreme temperature conditions (>200^\circC). [ABSTRACT FROM AUTHOR]

Patients with an elevated erythrocyte sedimentation rate (ESR) and non-specific symptoms often pose a diagnostic dilemma. PET/CT visualises infection, inflammation and malignancy, all of which may cause elevated ESR. The objective of this study was to determine the contribution of 18F-fluorodeoxglucose positron emission tomography (PET/CT) in the diagnostic work-up of referred patients with an elevated ESR, in whom initial routine evaluation did not reveal a diagnosis. We conducted a combined retrospective (A) and prospective (B) study in elderly (>50 years) patients with a significantly elevated ESR of≥50 mm/h and non-specific complaints. In study A, 30 patients were included. Malignancy (8 patients), auto-inflammatory disease (8 patients, including 5 with large-vessel vasculitis) and infection (3 patients) were suggested by PET/CT. Two scans showed non-specific abnormalities and 9 scans were normal. Of the 21 abnormal PET/CT results, 12 diagnoses were independently confirmed and two alternative diagnosis were made. Two diagnoses were established in patients with a normal scan. In study B, 58 patients in whom a prior protocolised work-up was non-diagnostic, were included. Of these, 25 PET/CT-scans showed suspected auto-inflammatory disease, particularly large-vessel vasculitis (14 cases). Infection and malignancy was suspected in 5 and 3 cases, respectively. Seven scans demonstrated non-specific abnormalities, 20 were normal. Of the 40 abnormal PET/CT results, 22 diagnoses were confirmed, 3 alternative diagnoses were established. Only one diagnosis was established in the 20 patients with a normal scan. In both studies, the final diagnosis was based on histology, clinical follow-up, response to therapy or additional imaging. In conclusion, PET/CT may be of potential value in the diagnostic work-up of patients with elevated ESR if routine evaluation reveals no diagnosis. In particular, large-vessel vasculitis appears to be a common finding. A normal PET/CT scan in these patients suggests that it is safe to follow a wait-and-see policy. [ABSTRACT FROM AUTHOR]

Objective: To quantify the environmental component of aetiology of overweight and obesity by examining the relationship between the degree of overweight in dogs and cats and the degree of overweight in their owners. Design: Cross-sectional study. Main outcome measures of the owners were weight, height (stature) and BMI. Of the animals, weight and divergence from ideal weight were measured by a veterinarian. Setting: Three veterinary clinics in Amsterdam, The Netherlands. Subjects: Dogs and cats, together with their owners, who visited the veterinary clinic. Dogs and cats had to be older than 1 year, and their owners had to be at least 21 years old. After exclusion, there remained forty-seven pairs of dogs and their owners and thirty-six pairs of cats and their owners. Results: We found a significant relationship between the degree of overweight of dogs and the BMI of their owners (r=0·31). Correction for length of ownership, gender and age of the animal, and gender, age, education level and activity score of the owner did not materially affect this relationship. However, after correction for the amount of time the dog was being walked each day, this relationship disappeared. No significant relationship was found between the degree of overweight of cats and the BMI of their owners. Conclusions: The degree to which dogs are overweight is, in contrast to the degree to which cats are overweight, related to the BMI of their owners. [ABSTRACT FROM AUTHOR]

This randomised double-blind, placebo-controlled, clinical trial investigated the effect of 3 months of treatment with calcium dobesilate on endothelium-dependent vasodilation, markers of endothelial function, blood pressure, and markers of oxidation in obese, male smokers. Vascular effects may depend on the type of vessel and we, therefore, investigated both smaller arteries, i.e. resistance arteries and small arterioles, and large conduit arteries. Vascular function was measured by acetylcholine- and sodium-nitroprusside-mediated vasodilation, and capillary recruitment, in the skin microcirculation; by forearm blood flow (FBF) responses to several agonists and to N-G-monomethyl l-arginine (l-NMMA) in the forearm vascular bed; by flow-mediated vasodilation in the brachial artery; and by determination of soluble levels of vascular cell adhesion molecule-1 (sVCAM-1), intercellular adhesion molecule-1 (sICAM-1) and E-selectin. Twenty-eight individuals received dobesilate and 24 placebo. No effect of calcium dobesilate on endothelial function, blood pressure or markers of oxidation was observed compared with placebo. The difference in acetylcholine-mediated vasodilation in the microcirculation was −52.1%-point (95% confidence interval −132.8 to 28.1); in sodium-nitroprusside-mediated vasodilation in the microcirculation, 2.6%-point (−95.1 to 100.2); in capillary recruitment, 2.5%-point (−6.8 to 11.7); in acetylcholine-induced increases in FBF (n=28), 23%-point (−173 to 126); in l-NMMA-induced reduction of basal FBF, −2.8%-point (−29.3 to 23.8); in flow-mediated vasodilation of the brachial artery, 0.3%-points (−2.7 to 3.3); in 24-h systolic blood pressure, 2.1 mmHg (−1.3 to 5.5); in soluble VCAM-1, 54 ng/ml (−8 to 115); in soluble ICAM-1, 9 ng/ml (−49 to 67); in sE-selectin, −17 ng/ml (−44 to 11); in ketocholesterol 5 nM (−17 to 26); and in oxidised LDL −1.6 U/l (−6.7 to 3.5). We have shown that endothelial function, blood pressure, and markers of oxidation were not affected by 3 months of treatment with calcium dobesilate in mildly obese, smoking men. Thus, our data provide no evidence of an effect on vascular function of calcium dobesilate in humans. [Copyright &y& Elsevier]

Presents information on a study which described a power cycling in-test monitoring system to assess the reliability of different lead-free surface mount assemblies. Experimental details; Results and discussion; Conclusions.

The use of simulation has traditionally required a great deal of expertise. Simulation Interfaces to General Purpose Simulation Languages made simulation easier to use. However, for successfully building simulation models, modelling expertise is still required.Macros have been proposed as a tool within Simulation Interfaces which simplify the building of models. A macro in this context should be seen as a group of SimulationLanguage statements with a data interface to the user.The questions to be answered were: "What should a macro do and how should it be implemented?" The first objective of the work was to specify the macro functionality more tightly and then develop some macros.The wide range of macro applications allows categorising. An attempt was made to classify the different types of macros in a hierarchical structure. Implementation of macros inSIMAN® [1],showed difficulties such as nesting, attribute sharing, and code connectivity. To make data input for complete models less laborious, generic data interfaces were proposed. A simple model of a manufacturing cell is discussed, to show some of the above mentioned aspects. It became clear that macros could considetably speed up model building. However, bigger macros could reduce modelling flexibility to some extent. [ABSTRACT FROM PUBLISHER]

A patient who bred exotic turtles as a hobby presented with 2 episodes of severe diarrhea, the second of which was proven to be caused by turtle-associated salmonellosis that was contracted during treatment with a proton-pump inhibitor. The literature about reptile-associated salmonellosis is briefly reviewed. [ABSTRACT FROM AUTHOR]

Abstract: This paper describes the electrochemical characterisation of a range of gold and platinum microelectrode arrays (MEAs) fabricated by standard photolithographic methods. The inter-electrode spacing, geometry, numbers and dimensions of the electrodes in the arrays were found to influence the voltammetric behaviours obtained. Excellent correlation was found between experimental data and theoretical predictions employing published models of microelectrode behaviour. Gold MEAs were evaluated for their applicability to copper determination in a soil extract sample, where agreement was found between the standard analytical method and a method based on underpotential deposition—anodic stripping voltammetry (UPD-ASV) at the MEAs, offering a mercury-free alternative for copper sensing. [Copyright &y& Elsevier]