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Open access

Zbigniew Stropek and Krzysztof Gołacki

Abstract

The cylindrical samples of ‘Beni Shogun’ apples cultivar in a range of deformation velocities from 0.0002 to 1 m s−1 were studied using stress relaxation tests. In the work, experimental courses of the force response were described via the Maxwell model, and the effects of deformation velocity on the Maxwell model parameters as well as the maximum and residual force were determined. The maximum force increased with the increase of the deformation velocity, which proved the response of apple flesh to be of viscoelastic nature. The residual force described the state of the material after the strain and was much higher under the quasi-static than impact loading conditions. The three relaxation times decreased with the increasing deformation velocity. For the shortest relaxation time (order of magnitude 0.1 s) there was a rapid decrease in the velocities under the quasi-static loading conditions and it remained on a steady and low level under the impact loading conditions. A definite limit was observed between the medium relaxation time (order of magnitude 1 s) for the lowest deformation velocity of 0.0002 m s−1 and the other relaxation times obtained at higher deformation velocities. The values of the longest relaxation time (order of magnitude 100 s) were much larger under the quasi-static than the impact loading conditions.

Open access

Jiří Blahovec and Pavel Kouřím

Abstract

A combined thermal analysis (including a dynamic mechanical analysis and a dielectric thermal analysis) was applied to the cortex tissues of long-stored potatoes in the temperature range of 30-90°C, with the constant air relative humidity of 90%. Two heating rates, i.e. 1°C min−1 and 0.5°C min−1, were used for temperature scanning. The obtained results were found to differ in the inspected temperature range, indicating either a different mode of drying or differences in the starch gelatinization mechanism, the latter being usually controlled by water availability in contact with starch in both tests. The observed results indicate new possibilities in the cooking strategies that are usually applied to potatoes.

Open access

Pilar Legua, Maria R. Martinez-Cuenca, Ricardo Bellver and María Á. Forner-Giner

Abstract

In terms of growth, yield and fruit quality, three lemon varieties (‘Fino49’ F49, ‘Verna50’ V50 and ‘FinoElche’ FE) were tested on three new hybrid root stock selections (Forner-Alcaide 2324, Forner-Alcaide 418 and Forner-Alcaide 5). Yield was weighed within a nine year period and fruit quality was determined in two harvests. Tree size was similar on the Forner-Alcaide 5 and Forner-Alcaide 2324 rootstocks, but reduced by 50% on Forner-Alcaide 418. Forner-Alcaide 2324 and the Forner-Alcaide 5 rootstocks showed similar cumulative yield, while it was decreased by 66% in Forner-Alcaide 418. In all cases, ‘Verna50’ was the less efficient scion. Rootstock was found to significantly affect fruit quality variables. The Forner-Alcaide 418 rootstock induced the lowest peel thickness and peel percentage, but the highest juice content and colour index. Forner-Alcaide 5, together with Forner-Alcaide 418, showed the highest total soluble sugars. In conclusion, both the Forner-Alcaide 5 and Forner-Alcaide 2324 rootstocks generate standard tree size and high yield in the varieties tested, together with great fruit quality, being a suitable alternative for replacing C. macrophylla rootstock when used in lemon varieties. Forner-Alcaide 418 reduces tree size without decreasing yield efficiency and improves alternate-bearing of the harvest. Thus, it may have use in intensifying citrus production as it behaves as a dwarfing rootstock.

Open access

Cătălina Anca Cucoș, Radu Constantinescu, Ateș Barut, Iuliana Ionașcu and Constantin Vlăgioiu

Abstract

Chiari-like malformation represents a congenital anomaly that affects the bony cranial base and the hindbrain, leading to fluid filled cavities formation in the spinal cord, condition named Syringomyelia. This paper aims to assess the variety of the clinical signs and to evaluate the magnetic resonance imaging findings in thirty- seven Cavalier King Charles Spaniel dogs. The study was performed over a four-year period, from 2013 to 2017, all cases underwent neurological examination, full diagnostic work-up, including magnetic resonance imaging scans of the brain, cervical and upper thoracic spinal cord. Thirty-seven dogs were included in this study, 23 females and 14 males, with a mean age of 3.6±2.1years. The commonest clinical findings encountered were neuropathic pain and vocalization, seen in all 37 cases, followed by scratching, facial rubbing, paw licking, air licking, tail chasing, seizures and unilateral facial paralysis. Different grades of cerebellar herniation and cervical syrinxes were noted in all cases, other magnetic resonance imaging findings encountered were medullary kinking, presyrinx and ventriculomegaly. In establishing the diagnosis of the Chiari-like malformation and Syringomyelia, the breed, clinical history and the symptomatology are very important, but only magnetic resonance imaging technique can provide quantitative assessment of the nervous system lesions.

Open access

Anthony Singer, Eleni Markoutsa, Alya Limayem, Subhra Mohapatra and Shyam S. Mohapatra

Abstract

Biomedical Nanotechnology (BNT) has rapidly become a revolutionary force that is driving innovation in the medical field. BNT is a subclass of nanotechnology (NT), and often operates in cohort with other subclasses, such as mechanical or electrical NT for the development of diagnostic assays, therapeutic implants, nano-scale imaging systems, and medical machinery. BNT is generating solutions to many conventional challenges through the development of enhanced therapeutic delivery systems, diagnostic techniques, and theranostic therapies. Therapeutically, BNT has generated many novel nanocarriers (NCs) that each express specifically designed physiochemical properties that optimize their desired pharmacokinetic profile. NCs are also being integrated into nanoscale platforms that further enhance their delivery by controlling and prolonging their release profile. Nano-platforms are also proving to be highly efficient in tissue regeneration when combined with the appropriate growth factors. Regarding diagnostics, NCs are being designed to perform targeted delivery of luminescent tags and contrast agents that enhance the NC -aided imaging capabilities and resulting diagnostic accuracy of the presence of diseased cells. This technology has also been advancing the ability for surgeons to practice true precision surgical techniques. Incorporating therapeutic and diagnostic NC-components within a single NC can facilitate both functions, referred to as theranostics, which facilitates real-time in vivo tracking and observation of drug release events via enhanced imaging. Additionally, stimuli-responsive theranostic NCs are quickly developing as vectors for tumor ablation therapies by providing a model that facilitates the location of cancer cells for the application of an external stimulus. Overall, BNT is an interdisciplinary approach towards health care, and has the potential to significantly improve the quality of life for humanity by significantly decreasing the treatment burden for patients, and by providing non-invasive therapeutics that confer enhanced therapeutic efficiency and safety

Open access

Rukiye Nur Kaçmaz, Bülent Yılmaz, Mehmet Sait Dündar and Serkan Doğan

Abstract

Computer-aided detection is an integral part of medical image evaluation process because examination of each image takes a long time and generally experts’ do not have enough time for the elimination of images with motion artifact (blurred images). Computer-aided detection is required for both increasing accuracy rate and saving experts’ time. Large intestine does not have straight structure thus camera of the colonoscopy should be moved continuously to examine inside of the large intestine and this movement causes motion artifact on colonoscopy images. In this study, images were selected from open-source colonoscopy videos and obtained at Kayseri Training and Research Hospital. Totally 100 images were analyzed half of which were clear. Firstly, a modified version of histogram equalization was applied in the pre-processing step to all images in our dataset, and then, used Laplacian, wavelet transform (WT), and discrete cosine transform-based (DCT) approaches to extract features for the discrimination of images with no artifact (clear) and images with motion artifact. The Laplacian-based feature extraction method was used for the first time in the literature on colonoscopy images. The comparison between Laplacian-based features and previously used methods such as WT and DCT has been performed. In the classification phase of our study, support vector machines (SVM), linear discriminant analysis (LDA), and k nearest neighbors (k-NN) were used as the classifiers. The results showed that Laplacian-based features were more successful in the detection of images with motion artifact when compared to popular methods used in the literature. As a result, a combination of features extracted using already existing approaches (WT and DCT) and the Laplacian-based methods reached 85% accuracy levels with SVM classification approach

Open access

Jan Trnka, Vojtěch Kumbár, Šárka Nedomová, Roman Pytel and Jaroslav Buchar

Abstract

For the purpose of this paper, sugar beet roots were loaded by creating the impact of aluminium bars falling from different heights. The time history of the force at the contact between the sugar beet root and the bar was measured. The response of the sugar beet root to the impact was evaluated in terms of surface displacement. This displacement was measured using a laser vibrometer. The displacement was studied in the time and frequency domain during the postharvest period, up to 71 days after crop collection. The measured parameters describing the sugar beet response were significantly sensitive to the storage duration, namely in the frequency domain. Correlations between the storage duration and the main parameters of both the force and surface displacement were identified (p < 0.05).

Open access

Imtiaz A. Dahri, Ahmed A. Tagar, Jan Adamowski, Naimatullah Leghari, Ali R. Shah and Shakeel A. Soomro

Abstract

Long-term soil disturbance due to regular tillage destroys the soil structure, particularly by reducing the soil organic matter content. This, in turn, can lead to declining crop yields. This study assessed the influence of wheat (Triticum æstivum L.) straw incorporation and timing prior to seeding at 6 Mg ha−1 (S+), relative to no straw (S), on maize (Zea mays L.) growth and yield parameters, as well as on soil characteristics. There were four intervals between straw incorporation and maize seeding, i.e. 60, 45, 30 and 15 days before sowing. Compared to the S (control), soil dry bulk density increased (p ≤ 0.05) under all S+ treatments. A significantly greater proportion of undesirable small aggregates (<0.5 mm), and a lesser proportion of desirable medium sized (0.5-8.0mm) aggregates, occurred under S treatment, as compared to S60+ treatment. A similar, but less pronounced, trend was observed under S45+ treatment. This trend was also evident for the S30+ and S15+ treatments. Generally, incorporation of straw 60 days prior to sowing led to achieving the best soil structure in terms of aggregation. Compared to S, the soil organic matter showed a weakly significant (0.05 ≤ p 0.06) increase under straw amendment. Seedling emergence, plant height, cob length, the number of grain rows per plant, the number of grains per cob, as well as 1000 grain weight and yield were the highest under S60+, and the lowest under S. The present study suggests that more research is necessary over longer time periods between straw incorporation and seeding on different crops, and in different soil types, in order to study the effects on soil properties, and on the growth and yield of crops.

Open access

Bogna Uździcka, Marcin Stróżecki, Marek Urbaniak and Radosław Juszczak

Open access

Jadwiga Stanek-Tarkowska, Ewa A. Czyż, Anthony R. Dexter and Cezary Sławiński

Abstract

The aim of this study was to quantify soil properties, microbial biodiversity and crop yield under two tillage systems used for winter wheat production in monoculture. The study was conducted in the period 2013-2016, on a long-term field experiment on a silt loam at the Krasne Research Station near Rzeszów, Poland. Traditional tillage involved soil inversion whereas reduced tillage was a non-inversion system. The following soil properties: chemical (soil organic carbon, pH, available P, K, Mg), physical (soil bulk density, water content, stability in water), and biological (the diversity of diatoms) were measured on samples collected throughout the growing season and at harvest. Soil organic carbon content, water content and bulk density in the 0-5 and 5-10 cm layers were greater in reduced tillage than in traditional tillage. Under reduced tillage the amount of readily dispersible clay was reduced giving increased soil stability in water. Soil under reduced tillage had greater diversity of diatoms (139 taxa) than that under traditional tillage (102 taxa). Wheat yields were positively correlated with precipitation, soil water content and soil organic carbon, and negatively correlated with readily dispersible clay.