Fabrication of conductive Ag/AgCl/Ag nanorods ink on Laser-induced graphene electrodes on flexible substrates for non-enzymatic glucose detection.

An unusual strategy was designed to fabricate conductive patterns for flexible surfaces, which were utilized for non-enzymatic amperometric glucose sensors. The Ag/AgCl/Ag quasi-reference ink formulation utilized two reducing agents, NaBH[Formula: see text] and ethylene glycol. The parameters of the ink, such as sintering time and temperature, NaBH[Formula: see text] concentration, and layer number of coatings on flexible laser-induced graphene (LIG) electrodes were investigated. The conductive Ag/AgCl/Ag ink was characterized using electrochemical and surface analysis techniques. The electrocatalytic activity of Ag/AgCl/Ag NRs can be attributed to their high surface area, which offer numerous active sites for catalytic reactions. The selectivity and sensitivity of the electrodes for glucose detection were investigated. The XRD analysis showed (200) oriented AgCl on covered Ag NRs, and with the addition of NaBH[Formula: see text], the intensity of the peaks of the Ag NRs increased. The wide linear range of non-enzymatic sensors was attained from 0.003 to 0.18 mM and 0.37 to 5.0 mM, with a low limit of detection of 10 [Formula: see text]M and 20 [Formula: see text]M, respectively.The linear range of enzymatic sensor in real sample was determined from 0.040 to 0.097 mM with a detection limit of 50 [Formula: see text]M. Furthermore, results of the interference studies demonstrated excellent selectivity of the Ag/AgCl/Ag NRs/LIG electrode. The Ag/AgCl/Ag NRs on the flexible LIG electrode exhibited excellent sensitivity,long-time stablity,and reproducibility. The efficient electroactivity were deemed suitable for various electrochemical applications and biosensors.

Exploring Water Governing System Fit Through a Statistical Mechanics Approach.

Water governing systems are twisted with complex interplays among levels and scales which embody their structures. Typically, the mismatch between human-generated and natural systems produces externalities and inefficiencies reflectable in spatial scales. The largely known problem of fit in water governance is investigated to detect the issues of fit between administrative/institutional scales and the hydrological one in a lake basin. To implement the idea, constraining the level of analysis interlinked to the concentrated levels of administration in spatial scales, the fit of the governing system was analyzed by means of statistical mechanics. Modeling the structure of water demand/supply governing system in a given region through the Curie-Weiss Mean Field approximation, the system cost in relation to its structure and fit was appraised and compared with two other conceptual structures in the Urmia Lake Basin in Iran. The methodology articulated an analysis framework for exploring the effectiveness of the formulated water demand/supply governing system and its fit to the relevant hydrological system. The findings of this study may help developing strategies to encourage adaptations, rescaling/reforms for effective watershed management.

Digital volumetric measurement of cutaneous leishmaniasis lesions: Blur estimation method.

BACKGROUND: Cutaneous leishmaniasis is a common parasitic infestation in Iran. With recent advantages in digital imaging, we have devised a novel non-contact objective method of measuring lesions. AIM: The aim of the study was to design a software system that analyzes images of cutaneous leishmaniasis lesions, objectively assess and monitor volume. METHODS: A photographic technique along with an image processing algorithm was applied to extract a three-dimensional map of the lesion from a simple two-dimensional picture. This method recovers depth on the basis of blur estimation. A macro lens with a low depth of field was used to blur the objects out of focus. To assess and compare the results, a polymer mold of the corresponding lesion was made and filled with liquid. The volume of liquid corresponded to the volume of the lesion. A total of thirty-seven patients were enrolled, and 48 lesions were analyzed. RESULTS: The mean volume measured by image processing was 159 µl (range: 8-685 µl), in comparison to an average of 170 µl (range: 6-800 µl) obtained from the molds. This was not significantly different. Statistical analysis by the Pearson correlation test showed a 'very good fit' correlation between these measured volumes (P < 0.001, r = 0.938). LIMITATION: The location and height of lesions were two important limitations in implementing this technique. If the lesion location is in the curvature region of body or the lesion height is less than 1 mm or more than 1 cm, this method will lose precision and accuracy. CONCLUSION: Image processing with blur estimation technique is an accurate and precise method to measure the volume of lesions in cutaneous leishmaniasis.

Study of the effect of mechanical pressure on determination of position and size of tumor in biological phantoms.

Diffuse optical tomography (DOT) is an emerging oncological imaging modality that is based on a near-infrared optical technique. DOT provides the spatial volume and depth of tumors by determination of optical properties of biological tissues, such as the absorption and scattering coefficients. During a DOT, the optical fibers are kept in contact with biological tissues that introduce a certain amount of pressure on the local biological tissue. Due to this pressure, the shape of the organ, for instance a breast, deforms. Moreover, this pressure could influence the intrinsic characteristics of the biological tissue. Therefore, pressure can be an important parameter in DOT. In this paper, the effects of pressure on the determination of the size and position of a tumor in biological phantoms are studied. To do so, tissue-like phantoms that are made of intralipid, Indian ink, and agar are constructed. Defects with optical properties similar to those of tumors are placed inside the phantoms. Then various values of pressure are applied to the phantoms. Subsequently, the optical properties of phantoms as well as the position and size of the tumor are reconstructed by inverse models based on the boundary integral method. The variations of reconstructed data induced by pressure are studied. The results demonstrate that pressure causes an increase in the scattering coefficient.