PEG-based hydrogel-coated test strip for on-site urea determination

The urea test strip was prepared using polyethyleneglycol based hydrogel, urease and commercial pH-indicator paper. The swelling behavior of hydrogel indicated the ability of the urea to penetrate into the matrix and allowing the test strip to respond in a short time. The color formed on the strip was distinguished by naked eyes in one minute at room temperature. The linear range for urea was 20–200?mg/dL. The assays have good reproducibility. Relative standard deviation values were found within the range of 3.37–12.95% and 1.68–9.54% for intra- and inter-day assays, respectively.     

Electrospinning of nanofibers from non-polymeric systems: polymer-free nanofibers from cyclodextrin derivatives

High molecular weight polymers and high polymer concentrations are desirable for the electrospinning of nanofibers since polymer chain entanglements and overlapping are important for uniform fiber formation. Hence, the electrospinning of nanofibers from non-polymeric systems such as cyclodextrins (CDs) is quite a challenge since CDs are cyclic oligosaccharides. Nevertheless, in this study, we have successfully achieved the electrospinning of nanofibers from chemically modified CDs without using a carrier polymer matrix. Polymer-free nanofibers were electrospun from three different CD derivatives, hydroxypropyl-β-cyclodextrin (HPβCD), hydroxypropyl-γ-cyclodextrin (HPγCD) and methyl-β-cyclodextrin (MβCD) in three different solvent systems, water, dimethylformamide (DMF) and dimethylacetamide (DMAc). We observed that the electrospinning of these CDs is quite similar to polymeric systems in which the solvent type, the solution concentration and the solution conductivity are some of the key factors for obtaining uniform nanofibers. Dynamic light scattering (DLS) measurements indicated that the presence of considerable CD aggregates and the very high solution viscosity were playing a key role for attaining nanofibers from CD derivatives without the use of any polymeric carrier. The electrospinning of CD solutions containing urea yielded no fibers but only beads or splashes since urea caused a notable destruction of the self-associated CD aggregates in their concentrated solutions. The structural, thermal and mechanical characteristics of the CD nanofibers were also investigated. Although the CD derivatives are amorphous small molecules, interestingly, we observed that these electrospun CD nanofibers/nanowebs have shown some mechanical integrity by which they can be easily handled and folded as a free standing material.     

Analysis of modeling effort and impact of different levels of detail in building information models

The main objectives of this paper are to evaluate the modeling effort associated with generating building information modeling (BIM) at different levels of detail (LoD) and the impact of LoD in a project in supporting mechanical, electrical and plumbing (MEP) design coordination. Results show an increase in total modeling time ranging from doubling the modeling effort to eleven folding it, when going from one LoD to another. When comparing modeling time per object, rates ranged from 0.2 (decreased modeling time) to 1.56 (increased modeling time). Based on the experiments done in MEP design coordination, it was observed that the automatic clash detection process using BIMs, with its consistently higher recall rate, provides a more complete identification of clashes, with the cost of false positives (low precision). This study showed that additional modeling effort can lead to more comprehensive analyses and better decision support during design and construction.     

Evaluation of the electrochemical properties of 3-hydroxyflavone using voltammetric methods

Electrochemical behavior of ring C of 3-hydroxyflavone (3-HF) has been investigated by cyclic and differential pulse voltammetry, using a glassy carbon electrode (GCE) in different buffer systems. It exhibited a sensitive diffusion controlled anodic peak at 0.70 V (vs Ag/AgCl) in a buffer system at pH 2.0. At higher pH, 8.0, while the peak at 0.70 V shifted to 0.41 V, a new peak at 0.8 V appeared. Moreover, electrochemical method was applied to investigate the antioxidant effect and metal chelating properties of 3-HF with Cd²⁺, Cu²⁺, Hg²⁺ and Pb²⁺ as they could have possible toxicological effects, for which fluorescence technique were also applied. Antioxidant effect was determined in terms of trolox equivalent antioxidant capacity (TEAC) using the peak areas of cyclic voltammetry (CV), which indicated that 1.0 mM 3-HF is equivalent to 0.2 mM of trolox. Such a result might be another indication of the importance of hydroxyl groups on the other rings of flavones. Electrochemical and fluorescence spectroscopic methods revealed that the best interactions of the cations could be obtained depending on the pH of the medium. Selective interactions of Cd²⁺ and Cu²⁺ at pH 2 and 7, respectively, were observed.     

Ultrasound as pretreatment for drying garlic slices in microwave and convective dryer

Food Science and Biotechnology - The effects of ultrasound pretreatment (US) before hot air drying (HAD) and microwave drying (MWD) of garlic slices were investigated. For this aim ultrasonic bath...     

Etiopathogenesis and clinical presentation of carotid body tumors

The carotid body (CB) is a highly specialized small organ located at the bifurcation of the common carotid artery in the neck and plays an important role in acute adaptation to hypoxia. The most common diseased state of the carotid body is its enlargement (i.e., the CB paraganglioma), which can be caused by a genetic predisposition (hereditary paraganglioma, PGL) and by chronic hypoxic stimulation. The CB is the most common tumor site in head and neck paragangliomas. Currently, inactivating germline mutations in the mitochondrial complex II subunits SDHB, SDHC, and SDHD have been identified as genetic risk factors for CB tumors (CBTs). Another locus at chromosome 11q13, identified by linkage analysis in a single family, may harbor a fourth susceptibility gene. Although CBTs are mostly slow-growing and benign, they can cause significant morbidity because of their proximity to major arteries and nerves in the head and neck. Here, we review the etiological factors implicated in the development of CBTs and provide information pertaining to their clinical presentation. Although CBTs are rare, they have the potential to provide unique insights for tumorigenesis and oxygen sensing and signaling mechanisms.     

A line based pose representation for human action recognition

In this paper, we utilize a line based pose representation to recognize human actions in videos. We represent the pose in each frame by employing a collection of line-pairs, so that limb and joint movements are better described and the geometrical relationships among the lines forming the human figure are captured. We contribute to the literature by proposing a new method that matches line-pairs of two poses to compute the similarity between them. Moreover, to encapsulate the global motion information of a pose sequence, we introduce line-flow histograms, which are extracted by matching line segments in consecutive frames. Experimental results on Weizmann and KTH datasets emphasize the power of our pose representation, and show the effectiveness of using pose ordering and line-flow histograms together in grasping the nature of an action and distinguishing one from the others.