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Due to the growing demand for alternative green fuels, biodiesel remains a focal point of scientific research. While chemical biodiesel production, mostly from edible oils, has been established worldwide for years, enzymatic synthesis and the utilisation of raw materials like waste or inedible oils and fats are increasingly preferred, primarily due to economic and environmental considerations. The aim of this study was to perform enzymatic biodiesel synthesis with Burkholderia cepacia lipase using selected waste cooking vegetable oils and animal fat, and to correlate the resulting fatty acid methyl esters (FAME) with lipase substrate specificity and main specific characteristics of the selected waste feedstock (such as fatty acid profile, free fatty acid content, peroxide and iodine values). The listed characteristics of the oils/fat were determined using standard methods, while biodiesel was synthesised through transesterification of the selected waste oils/fat with methanol in the presence of a lipase catalyst. Analysis of FAME during 24 h of biodiesel synthesis from waste cooking vegetable oils revealed that a one-hour reaction time was sufficient to achieve a yield of over 97 % of FAME. Conversely, when utilising waste cooking animal fat as a substrate, the minimum yield of 96.5 %, as per European standard (EN 14214), was not achieved even after 24 h of synthesis. According to the correlation matrix, the highest positive correlation was found between iodine value and the resulting FAME. The waste cooking vegetable oil with the highest iodine number (123.88 ± 2.41 g I2/100 g) yielded the highest proportion of methyl esters after 1 h of synthesis. A statistically significant positive correlation was found between FAME and the iodine and peroxide values, suggesting these parameters as indicators of waste oil suitability for biodiesel synthesis. This study is a contribution to further research on potential substrates for biodiesel synthesis from waste streams.

This research studies the influence of the addition of defatted press cakes (from the production of hazelnut, camelina, pumpkin, and hemp seed oil) on nutritionally important components: fibre, resistant starch, polyphenols, hydroxymethylfurfural (HMF), and acrylamide in directly and indirectly expanded snacks. The amounts of press cakes added to corn grits were 3, 6, and 9%. Extrusion was carried out in a laboratory single-screw extruder. For indirectly expanded products (SCFX), supercritical CO2 was injected during extrusion, and secondary expansion was completed in the microwave oven. The type and content of press cake, as well as the type of product, significantly influenced total polyphenol content and antioxidant activity. Press cakes increased the contents of both soluble and insoluble fibre (from 1.94% d. m. and 1.28% d. m. for extrudates without press cakes up to 3.17% d. m. and 6.94% d. m. for SCFX extrudates with press cakes, respectively), and resistant starch was not markedly influenced by their addition. The influence of the content of press cake on HMF was not significant, whereas the type of cake and the type of extrusion influenced HMF significantly. In a raw mixture of corn grits with 3% of pumpkin press cake, HMF was below the limit of detection, and the highest content was found in the classically extruded sample with the addition of 9% of camelina press cake (580 ppb). In all samples, the acrylamide content was below the limit of detection, indicating that safe products were obtained. This research shows potential for the implementation of supercritical CO2 extrusion in the production of safe, nutritionally improved snack products. Future research might bring about the design of cost-effective processes applicable in the industry.

The high stiffness of cement-bound aggregate (CBA) is recognized as its main drawback. The stiffness is described by the modulus of elasticity, which is difficult to determine precisely in CBA. Incorporating rubber in these mixtures reduces their stiffness, but mathematical models of the influence of rubber on the mechanical characteristics have not previously been defined. The scope of this research was to define a prediction model for the compressive strength (fc), dynamic modulus of elasticity (Edyn) and static modulus of elasticity (Est) based on the measured ultrasonic pulse velocity as a non-destructive test method. The difference between these two modules is based on the measurement method. Within this research, the cement and waste rubber content were varied, and the mechanical properties were determined for three curing periods. The Edyn was measured using the ultrasonic pulse velocity (UPV), while the Est was determined using three-dimensional digital image correlation (3D DIC). The influence of the amount of cement and rubber and the curing period on the UPV was determined. The development of prediction models for estimating the fc and Est of CBA modified with waste rubber based on the non-destructive test results is highlighted as the most significant contribution of this work. The curing period was statistically significant for the prediction of the Est, which points to the development of CBA elastic properties through different stages during the cement-hydration process. By contrast, the curing period was not statistically significant when estimating the fc, resulting in a simplified, practical and usable prediction model.

We sought to investigate whether quantitative parameters from a dynamic contrast-enhanced study can be used to differentiate cancer from normal tissue and to determine a cut-off value of specific parameters that can predict malignancy more accurately, compared to the obturator internus muscle as a reference tissue. This retrospective study included 56 patients with biopsy proven prostate cancer (PCa) after multiparametric magnetic resonance imaging (mpMRI), with a total of 70 lesions; 39 were located in the peripheral zone, and 31 in the transition zone. The quantitative parameters for all patients were calculated in the detected lesion, morphologically normal prostate tissue and the obturator internus muscle. Increase in the Ktrans value was determined in lesion-to-muscle ratio by 3.974368, which is a cut-off value to differentiate between prostate cancer and normal prostate tissue, with specificity of 72.86% and sensitivity of 91.43%. We introduced a model to detect prostate cancer that combines Ktrans lesion-to-muscle ratio value and iAUC lesion-to-muscle ratio value, which is of higher accuracy compared to individual variables. Based on this model, we identified the optimal cut-off value with 100% sensitivity and 64.28% specificity. The use of quantitative DCE pharmacokinetic parameters compared to the obturator internus muscle as reference tissue leads to higher diagnostic accuracy for prostate cancer detection.

The paper deals with an optimization problem in an electricity distribution network with different types of distributed generation and a battery storage system in terms of a smart grid concept. The optimization problem considers two objectives, namely, the annual energy losses and the exchange of energy with the higher-level power grid. The decision variables of the problem are the allocation of the different distributed generation units and the battery storage system, the annual power profiles of the controllable distributed generation and the battery storage system, and the power factor profiles of the controllable and noncontrollable distributed generation. All decision variables are solved simultaneously in a single optimization problem. The variable load shapes of the grid consumers and the profiles of the photovoltaic and wind power systems are considered in the study. All data are observed at the annual level with hourly resolution. The problem solving method uses computational intelligence techniques, namely, metaheuristic optimization methods and artificial neural networks. The study proposes a framework for optimizing the decision variables in the planning phase of distributed generation and battery storage, and for controlling the variable power and power factor profiles based on an artificial neural network in the implementation phase. The optimization problem is solved with a power system simulation program and a metaheuristic optimizer in cosimulation synergy. The three cases of distributed generation and battery storage are considered simultaneously. The proposed method is applied to the test grid operator IEEE with 37 buses, and reductions in annual energy losses and energy exchange are obtained in the ranges 34–86% and 41–99%, respectively.

Introduction: Spasmodic dysphonia (SD) and muscle tension dysphonia (MTD ) are two different disorders with different etiology that influence the quality of voice, characterized by similar perceptual and acoustic features. It is known that the emergence of compensatory mechanisms can lead to problems in the differential diagnosis of adductor spasmodic dysphonia (ADSD) and primary hyperkinetic dysphonia (MTD) by fiberoptic video laryngoscopy (FLS). So, the goal of this paper is to determine acoustic objective differential diagnostic criteria for distinguishing between SD and MTD and confirm clinical laryngeal findings by FLS and diagnosis. Patients and methods: Eight women with MTD and eight women with SD diagnosed at the Department of Audiology and Phoniatrics of the Clinical Hospital Center Rijeka participated in this study. A phoniatrician and a speech language pathologist (SLP) participated in the diagnostic procedure. FLS and SLP assessment were performed. Samples of extended phonation of the vowel /a/ and reading were collected. The samples were analyzed in the computer program Praat, which was used to measure the duration of words and sentences, the percentage of brakes in phonation and words, and cepstral peak prominence (CPPS). Results: This study found that four acoustic parameters (word duration, sentence duration, percentage of brakes /a/, percentage of brakes (word)) separate SD and MTD well. CPPS does not separate these two groups of patients. Furthermore, it was confirmed that by analyzing the phonation pattern of the vowel /a/ in the computer program Praat it is possible to classify these two disorders with a cut-off value of 5%. If the percentage of delay in the phonation pattern of the vowel /a/ is greater than or equal to 5%, it is very likely that it is a voice sample of a person with SD. Conclusion: Acoustic measures applicable in clinical conditions were determined. It has been shown that acoustic analysis of voice samples can provide valuable differential diagnostic data. This suggests that acoustic analysis of voice samples should be an integral part of the standard diagnostic protocol for voice disorders besides FLS.

The aim was to analyze patients with clinical diagnosis of triangular fibrocartilage complex (TFCC) lesion using standard x-ray, ultrasound, conventional magnetic resonance imaging (MRI) and MR arthrography (MRA); to evaluate the accuracy of MRA compared with MRI in the diagnosis of this lesion; and to evaluate ultrasound as a method of diagnosing TFCC lesion. We analyzed 72 patients (46 female and 26 male; age range, 22-61 years; mean age 37 years; 50 right and 22 left wrists) with suspected TFCC lesion with clinical examination, standard x-rays, and ultrasound. We confirmed patients with traumatic TFCC injury on MRI and MRA. Ultrasound found 13 lesions in 72 patients with suspected TFCC lesions. Conventional MRI found 66 and MRA 68 TFCC lesions. Ultrasound is useful for visualizing intra-articular effusion, soft tissue, bone surface, and for early detection of occult fractures. MRI is a better diagnostic modality, fully able to visualize the TFCC cartilage and ligaments. MRA is consistently and accurately able to visualize structural abnormalities of TFCC.

The main problem in planning the optimal operation of renewable energy sources and battery storage systems is the amount of data that must be considered to cover an entire observation period. If the observation period is one year, the characteristic days or averaged data (daily, weekly or monthly averages) are considered to reduce the number of data. Since the average values of the entered data differ from the actual values, it is better to work with hourly or 15-min data at the annual level. The study presents a framework for solving the problem of the optimal allocation and operation of renewable energy sources and battery storage systems. The proposed method simultaneously solves the optimal allocation and energy management problem considering hourly data at the annual level. The fuzzy inference-based system is proposed for scheduling optimal profiles of battery storage systems and renewable energy sources. The developed fuzzy inference system manages the power factors of the photovoltaic and wind power systems, the power factor and output of the biogas plant, and the operating status of the battery storage system. The presented method simultaneously finds the optimal parameters of the energy management system and the optimal allocation and operation of the renewable energy sources and the battery storage system. The developed method is based on the calculation of steady-state power flow. The proposed method is to be used in the design phase for the installation of various renewable energy sources and battery storage systems. In addition, the method is intended to be used to optimally control the power output of energy sources and the operation of energy storage systems during steady-state operation in order to operate the distribution network with minimum annual active energy losses. The developed method is applied to the test distribution system IEEE with 37 nodes. The reduction in annual energy losses in the tested distribution system is about 80% compared to the base case without renewable energy sources and battery storage system.

The aim of this research is to analyse the reliability of the existing methods, and find new ones, for assessing brick resistance to freeze-thaw cycles. A series of bricks were tested against a range of properties; compressive strength ratios pre- to post-freezing and Maage’s factor, were calculated. Using a database created in this way, an analysis of existing classifiers was carried out and new ones were established based on which bricks could be classified into resistant and non-resistant to freeze-thaw cycles. The median pore radius, the ratio of compressive strengths pre- to post-freezing and the water desorption coefficient at 180-360 minutes proved to be good classifiers with a clearly specified cut-off for the distinction between resistant and non-resistant bricks with an acceptable risk of a wrong decision. The ratio of compressive strengths pre to post freezing and the water desorption coefficient at 180-360 minutes were described using the pore system in the brick.

Pasta is one of the most popular meals in the world. It is affordable, easy to combine with other foods and easy to cook. Unfortunately, pasta is energy-rich and nutrient-poor. Whole-wheat pasta is somewhat better in nutritional quality, but further improvements may be made. One option is to add different raw materials and specific nutritive components (vitamins, polyphenols, fiber, protein, etc.) to semolina. However, this approach changes its physicochemical properties, e.g. cooking loss, texture, etc., which cannot be disregarded. The current research investigates possibilities for production of barley-enriched pasta with acceptable cooking qualities. To ensure the beneficial health effects of β-glucan, β-glucan-rich barley was selected asa starting material. Pasta enriched with 10–50% β-glucan-rich barley flour was produced in the mini-press and the laboratory extruder and then dried at low, medium and high temperature regimes. Colour, cooking quality and microstructure of the enriched pasta were investigated to determine its acceptability. The research showed that barley-enriched pasta of good cooking quality might be produced by selecting an optimal combination of suitable production parameters for forming and drying.

A speed tracking control method for induction machine is shown in this paper. The method consists of outer speed control loop and inner current control loop. Model predictive current control method without the need for calculation of the weighing factors is utilized for the inner control loop, which generates a continuous set of voltage reference values that can be modulated and applied by the inverter to the induction machine. Interesting parallels are drawn between the developed method and state feedback principles that helped with the analysis of the stability and controllability. Simple speed and rotor flux estimator is implemented that helps achieve sensorless control. Simulation is conducted and the method shows great performance for speed tracking in a steady state, and during transients as well. Additionally, compared to the finite control set predictive current control, it shows less harmonic content in the generated torque on the rotor shaft.

Aim: The aim of this study was to compare the most commonly used ultrasound parameters of elasticity and stiffness of the arterial wall in the detection of carotid subclinical atherosclerosis (SA) in vascular healthy men with one of the most prominent cardiovascular risk factors (CVRF). Methods: Total of 120 vascular healthy men between 33 and 59 years of age ( (SD)=49.7(6.93)) were allocated into hypertension, diabetes, smokers and control group of respondents without CVRF. Ultrasound examination of carotid arteries was used to measure intima-media thickness and maximal and minimal lumen diameter. Along with the blood pressure of all respondents, the following markers of elasticity/stiffness of arterial wall were calculated: distensibility coefficient (DC), compliance coefficient (CC), Young's elasticity modulus (YEM) and β stiffness index (β). Results: DC, CC and β indicated significantly lower elasticity and higher stiffness of arterial wall in hypertension and diabetic groups of respondents without CVRF (multiple comparison, p

High stroma proportion appears to be a very important prognostic factor in esophageal and breast cancer. Previous researches have shown that it might have a similar effect on colorectal cancer. The aim of this study was to determine whether tumor stroma proportion influenced patient survival. This retrospective study included 236 patients with colorectal cancer having undergone surgery in 2006 and 2007 at Osijek University Hospital Center. Location with the highest stroma proportion at the site of deepest tumor invasion was determined. Patients were divided into the groups with high stroma proportion (>50%) and low stroma proportion (≤50%). Stroma proportion showed a statistically significant correlation with tumor stage. Kaplan-Meier survival curves yielded a statistically significant difference in patient overall survival (Cox ph model p=0.016) and progressionfree survival (Cox ph model, p=0.0188) according to stroma proportion. Study results showed a statistically significantly shorter overall survival and progression-free survival in patients with high stroma proportion.

The paper presents a simulation model for the electric vehicles (EV) drive with Lithium-Ion batteries. Explanations of all the input parameters are given. Analysis of the dynamic characteristics of Lithium-Ion batteries was carried out through simulations on standardized driving regime (urban and highway drive cycles). Finally, recuperation of breaking energy of EV is explained.

Introduction: The Self-Evaluation of Communication Experiences after Laryngectomy (SECEL) is a 35-item patient-reported questionnaire developed to address the communication needs of patients with laryngectomies. The aim was to translate, cross-culturally adapt, and validate the Croatian version. Methods: The SECEL was translated from English by two independent translators and back-translated by a native speaker, after which it was approved by an expert committee. The Croatian version of the Self-Evaluation of Communication Experiences after Laryngectomy questionnaire (SECEL:HR) was filled in by 50 laryngectomised patients who had completed their oncological treatment a year prior to inclusion in the study. Patients also filled in the Voice Handicap Index (VHI) and the Short Form Health Survey (SF-36) on the same day. All patients completed the SECEL:HR twice, the second time being 2 weeks after the initial test. Maximum phonation time and diadochokinesis of articulation organs were used for objective assessment. Results: Among the Croatian patients, the questionnaire was well-accepted and demonstrated good test-retest reliability and internal consistency for two out of three subscales. The correlations between VHI, SF-36, and SECEL:HR were moderate to strong. There were no significant differences between patients who are using oesophageal speech, tracheoesophageal speech, or the electrolarynx based on the SECEL:HR. Conclusion: Preliminary findings of the research indicate that the Croatian version of the SECEL has sufficient psychometric qualities, high reliability, and good internal consistency, with a Cronbach's alpha of 0.89 for the total score. The Croatian version of SECEL can be recommended as a reliable and clinically valid measure for the assessment of substitution voices in Croatian-speaking patients. [ABSTRACT FROM AUTHOR]

Cocoa shell is a by-product of the chocolate industry that is rich in dietary fiber and bioactive components. In this research, the influence of high voltage electric discharge (HVED) treatment on chemical and physical characteristics of the cocoa shell, i.e., the effects of applied time and frequencies on grinding ability, water binding capacity (WBC), dietary fibers and tannin content was investigated. HVED had a significant influence on the chemical and physical properties of cocoa shell, all of which could be linked to changes in fiber properties. Along with the fiber content, grinding ability and water binding capacity were increased. These properties have already been linked to fiber content and soluble/insoluble fiber ratio. However, this research implies that change in fiber properties could be linked to tannin formation via complexation of other polyphenolic components. Additional research is needed to verify this effect and to establish mechanisms of tannin formation induced by HVED and its influence on fiber quantification.

This paper presents a method for selecting the sampling time for induction machine parameter estimation from the machine line start measurements. the metaheuristic optimization method is used to find the optimal Prony exponential series approxiamtion of the line start transient current. From the optimal approximation, poles of the linearized induction machine model are computed and used to determine the optimal sampling time. the results show that sampling frequencies needed for parameter estimation are much lower than 1–15 kHz commonly used today. This reduces the necessary amount of collected data and the computing power needed for the estimation. the optimal sampling time is computed for the simulated and for the measured data. Referenced parameter estimation technique is tested for the measured transient showing benefits of using the optimal sampling time.

Interactions between polyphenols and fibers are important for polyphenol bioactivities, and have been studied in vitro with adsorption process and isotherms. However, the theoretical interpretations of adsorption potentially can be affected by the method of isotherm modeling. The aim was to study the interactions between β-glucan and quercetin derivatives (quercetin-3-glucoside, quercetin-3-galactoside, quercetin-3-rhamnoside) by studying adsorption, and to potentially improve the modeling of adsorption isotherms. Quercetin derivatives were determined by using spectrophotometric method. Experimental results were modeled with Langmuir, Dubinin-Radushkevich, and Hill isotherms using non-linear regression, linear regression, and improved non-linear regression. For improved non-linear regression, code in the R programming language was developed. All quercetin derivatives adsorbed onto the surface of β-glucan. Improved non-linear regression gave somewhat lower errors and may be the most appropriate for adsorption interpretation. According to isotherms obtained with improved regression, it may be suggested that adsorption is higher for rhamnoside and glucoside of quercetin than for quercetin-3-galactoside which agrees with experimental results. Adsorption could be a physical process. The spatial arrangement of hydroxyl (OH) groups on the glycoside part of quercetin could affect the adsorption. In conclusion, a novel approach using improved non-linear regression has been shown to be a useful, novel tool for adsorption interpretation.