Publications by authors named "J Hribar"

Background: Frequent blood glucose level (BGL) monitoring is essential for effective diabetes management. Poor compliance is common due to the painful finger pricking or subcutaneous lancet implantation required from existing technologies. There are currently no commercially available non-invasive devices that can effectively measure BGL.

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This paper presents a dielectric, all-optical thermal time-of-flight fluid flow velocity sensor. The proposed sensor utilizes a sequence of three short sections of optical fibers, which are positioned in a direction perpendicular to the measured fluid flow. One of these three fiber sections is highly doped with vanadium and acts as an optically controlled heater, while the other two fiber sections contain fiber Bragg gratings (FBG) that act as dynamic temperature sensors.

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This study presents the results of conventional aqueous (CE) and non-conventional ultrasound-assisted (UAE) extractions of polyphenolic compounds from lees extracts of red wine varieties (Merlot and Vranac). The effect of ultrasound extraction time (t, s), and amplitude (A,%) from a 400 W ultrasound processor with different ultrasonic probes diameters (Ds, mm) on the amount and profile of polyphenolic compounds in the obtained extracts was investigated and compared to CE. The optimal conditions resulting in maximum extraction of phenolic compounds were: Probe diameter of 22 mm, amplitude 90% and extraction time for Vranac wine lees 1500 s and for Merlot wine lees extraction time of 1361 s.

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is a deciduous tree commonly known as Mediterranean hackberry or the European nettle tree. The fruit of hackberry are seldom used for nutritional purposes. The nutritional and physicochemical properties of ripe hackberry fruit from Istria (Marasi village near Vrsar, Croatia) were determined, including water, total fiber, protein, vitamin, mineral, and phenolic contents.

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The objective of this study is to investigate the effects of irradiation from light-emitting diodes (LEDs) on several fruits during storage. To improve storage and increase the contents of some bioactive compounds, apple, tomato and red bell pepper fruits were exposed to yellow light emitted from the diodes at 590 nm. The contents of ascorbic acid, total phenolics, total flavonoids and several pigments were investigated, along with the antioxidant potential.

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