Manipulating postharvest quality and nutritional content of spinach

The high nutri tional value of leafy salads and convenience to the consumer has resulted in continuing growth of the leafy vegetable market . The shelf -life of leafy vegetables , including spinach, is relatively short (7-14 days) and is influenced by storage conditions. This project investigated the effect of storage temperature and light exposure on quality maintenance during the storage of baby leaf spinach. A series of experiments (Experiment s 1-5) were conducted to conclude that quality loss of spinach leaves is accel erated with increasing temperature and light intensity during storage , temperature having a greater effect (Experiment 5) . Low intensity light, however, improved leaf texture maintenance when compared with samples stored in the dark. In addition to observed responses, results from Experiment s 1 and 2 (reported in Chapter 3) helped to identify leaf textural and visual quality as the best indicators of shelf -life. The f resh produce industry is keen on developing new methods, e.g . pre- storage treatment s that will enhance or maintain nutritional value of the product, retain its colour and texture. There is enough evidence in the literature to s uggest that pre- storage hot water treatment might be a good option. M ost of the studies, however, have been conducted on lettuce . Thus, the decision was made to investigate whether hot water treatment is also a good solution for im proving the quality or extending the shelf -life of baby leaf spinach. Based on the results from Experiment s 6 and 7, it was concluded that hot w ater treatments have limited commercial potential for quality improvement of spinach vii Abstract The high nutri tional value of leafy salads and convenience to the consumer has resulted in continuing growth of the leafy vegetable market . The shelf -life of leafy vegetables , including spinach, is relatively short (7-14 days) and is influenced by storage conditions. This project investigated the effect of storage temperature and light exposure on quality maintenance during the storage of baby leaf spinach. A series of experiments (Experiment s 1-5) were conducted to conclude that quality loss of spinach leaves is accel erated with increasing temperature and light intensity during storage , temperature having a greater effect (Experiment 5) . Low intensity light, however, improved leaf texture maintenance when compared with samples stored in the dark. In addition to observed responses, results from Experiment s 1 and 2 (reported in Chapter 3) helped to identify leaf textural and visual quality as the best indicators of shelf -life. The f resh produce industry is keen on developing new methods, e.g . pre- storage treatment s that will enhance or maintain nutritional value of the product, retain its colour and texture. There is enough evidence in the literature to s uggest that pre- storage hot water treatment might be a good option. M ost of the studies, however, have been conducted on lettuce . Thus, the decision was made to investigate whether hot water treatment is also a good solution for im proving the quality or extending the shelf -life of baby leaf spinach. Based on the results from Experiment s 6 and 7, it was concluded that hot w ater treatments have limited commercial potential for quality improvement of spinach leaves

Polarization Analysis of p̄ Produced in pA Collisions

A quite simple procedure for the generation of a polarized antiproton beam could be worked out if antiprotons are produced with some polarization. In order to investigate this possibility measurements of the polarization of produced antiprotons have been started at a CERN/PS test beam. The polarization will be determined from the asymmetry of the elastic antiproton scattering at a liquid hydrogen target in the CNI region for which the analyzing power is well known. The data are under analysis and an additional measurement is done in 2018. Details on the experiment and the ongoing data analysis will be given

Acoustic Diagnostics of Electrical Origin Fault Modes with Readily Available Consumer-Grade Sensors

Acoustic diagnostics, traditionally associated with mechanical fault modes, can potentially solve a wider range of monitoring applications. Typically, fault modes are induced purposefully by the researcher through physical component damage whilst the system is shutdown. This paper presents low-cost real-time fault diagnostics of a previously unreported acute electrical origin fault that manifests sporadically during system operation with no triggering intervention. A suitability study into acoustic measurements from readily available consumer-grade sensors for low-cost real-time diagnostics of audible faults, and a brief overview of the theory and configuration of the wavelet packet transform (including optimal wavelet selection methods) and empirical mode decomposition processing algorithms is also included. The example electrical origin fault studied here is an unpredictable current instability arising with the PWM-controller of a BrushLess DC motor. Experimental trials positively detect 99.9 % of the 1160 resultant high-bandwidth torque transients using acoustic measurements from a USB microphone and a smartphone. While the use of acoustic techniques for detecting emerging electrical origin faults remains largely unexplored, the techniques demonstrated here can be readily adopted for the prevention of catastrophic failure of drive and power electronic components

Using jasmonates and salicylates to reduce losses within the fruit supply chain

The fresh produce industry is constantly growing, due to increasing consumer demand. The shelf-life of some fruit, however, is relatively short, limited by microbial contamination or visual, textural and nutritional quality loss. Thus, techniques for reducing undesired microbial contamination, spoilage and decay, as well as maintaining product’s visual, textural and nutritional quality are in high demand at all steps within the supply chain. The postharvest use of signalling molecules, i.e. jasmonates and salicylates seems to have unexplored potential. The focus of this review is on the effects of treatment with jasmonates and salicylates on the fresh produce quality, defined by decay incidence and severity, chilling injury, maintenance of texture, visual quality, taste and aroma, and nutritional content. Postharvest treatments with jasmonates and salicylates have the ability to reduce decay by increasing fruit resistance to diseases and reducing chilling injury in numerous products. These treatments also possess the ability to improve other quality characteristics, i.e. appearance, texture maintenance and nutritional content. Furthermore, they can easily be combined with other treatments, e.g. heat treatment, ultrasound treatment. A good understanding of all the benefits and limitations related to the postharvest use of jasmonates and salicylates is needed, and relevant information has been reviewed in this paper

Simplified automatic method for measuring the visual field using the perimeter ZERK 1

Background: Currently available perimeters have limited capabilities of performing measurements of the visual field in children. In addition, they do not allow for fully automatic measurement even in adults. The patient in each case (in any type of perimeter) has at his disposal a button which he uses to indicate that he has seen a light stimulus. Such restrictions have been offset in the presented new perimeter ZERK 1. Methods: The paper describes a new type of automated, computerized perimeter designed to test the visual field in children and adults. The new perimeter and proprietary software enable to carry out tests automatically (without the need to press any button). The presented full version of the perimeter has been tested on a head phantom. The next steps will involve clinical trials and a comparison with measurements obtained using other types of perimeters. Results: The perimeter ZERK 1 enables automatic measurement of the visual field in two axes (with a span of 870 mm and a depth of 525 mm) with an accuracy of not less than 1o (95 LEDs on each arm) at a typical position of the patient's head. The measurement can be carried out in two modes: default/typical (lasting about 1 min), and accurate (lasting about 10 min). Compared with available and known types of perimeters, it has an open canopy, proprietary software and cameras tracking the eye movement, automatic control of fixation points, light stimuli with automatically preset light stimulus intensity in the following ranges: 550-700 mcd (red 620-630 nm), 1100-1400 mcd (green 515-530 nm), 200-400 mcd (blue 465-475 nm). Conclusions: The paper presents a new approach to the construction of perimeters based on automatic tracking of the eye movements in response to stimuli. The unique construction of the perimeter and the software allow for its mobile use in the examination of children and bedridden patients

Fault Diagnosis of Three Phase Induction Motor Using Current Signal, MSAF-Ratio15 and Selected Classifiers

A degradation of metallurgical equipment is normal process depended on time. Some factors such as: operation process, friction, high temperature can accelerate the degradation process of metallurgical equipment. In this paper the authors analyzed three phase induction motors. These motors are common used in the metallurgy industry, for example in conveyor belt. The diagnostics of such motors is essential. An early detection of faults prevents financial loss and downtimes. The authors proposed a technique of fault diagnosis based on recognition of currents. The authors analyzed 4 states of three phase induction motor: healthy three phase induction motor, three phase induction motor with 1 faulty rotor bar, three phase induction motor with 2 faulty rotor bars, three phase induction motor with faulty ring of squirrel-cage. An analysis was carried out for original method of feature extraction called MSAF-RATIO15 (Method of Selection of Amplitudes of Frequencies – Ratio 15% of maximum of amplitude). A classification of feature vectors was performed by Bayes classifier, Linear Discriminant Analysis (LDA) and Nearest Neighbour classifier. The proposed technique of fault diagnosis can be used for protection of three phase induction motors and other rotating electrical machines. In the near future the authors will analyze other motors and faults. There is also idea to use thermal, acoustic, electrical, vibration signal together