Online Machine Vision-Based Modeling during Cantaloupe Microwave Drying Utilizing Extreme Learning Machine and Artificial Neural Network.

Online microwave drying process monitoring has been challenging due to the incompatibility of metal components with microwaves. This paper developed a microwave drying system based on online machine vision, which realized real-time extraction and measurement of images, weight, and temperature. An image-processing algorithm was developed to capture material shrinkage characteristics in real time. Constant-temperature microwave drying experiments were conducted, and the artificial neural network (ANN) and extreme learning machine (ELM) were utilized to model and predict the moisture content of materials during the drying process based on the degree of material shrinkage. The results demonstrated that the system and algorithm operated effectively, and ELM provided superior predictive performance and learning efficiency compared to ANN.

Estimating the Moisture Ratio Model of Cantaloupe Slices by Maximum Likelihood Principle-Based Algorithms.

As an agricultural plant, the cantaloupe contains rich nutrition and high moisture content. In this paper, the estimation problem of the moisture ratio model during a cantaloupe microwave drying process was considered. First of all, an image processing-based cantaloupe drying system was designed and the expression of the moisture ratio with regard to the shrinkage was built. Secondly, a maximum likelihood principle-based iterative evolution (MLP-IE) algorithm was put forward to estimate the moisture ratio model. After that, aiming at enhancing the model fitting ability of the MLP-IE algorithm, a maximum likelihood principle-based improved iterative evolution (MLP-I-IE) algorithm was proposed by designing the improved mutation strategy, the improved scaling factor, and the improved crossover rate. Finally, the MLP-IE algorithm and MLP-I-IE algorithm were applied for estimating the moisture ratio model of cantaloupe slices. The results showed that both the MLP-IE algorithm and MLP-I-IE algorithm were effective and that the MLP-I-IE algorithm performed better than the MLP-IE algorithm in model estimation and validation.

Predicting the Moisture Ratio of a Hami Melon Drying Process Using Image Processing Technology.

For food drying, moisture content and shrinkage are vital in the drying process. This paper is concerned with the moisture ratio modeling and prediction issues of the Hami melon drying process. First, an experimental system was developed; it included an adjustable-power microwave drying unit and an image-processing unit. The moisture contents and the areas of Hami melon slices at different times were sampled in real time. Then, the expression of the moisture ratio with regard to shrinkage was derived by using the Weierstrass approximation theorem. A maximum likelihood fitness function-based population evolution (MLFF-PE) algorithm was then put forward to fit the moisture ratio model and predict the moisture ratio. The results showed that the proposed MLFF-PE algorithm was effective at fitting and predicting the moisture ratio model of the drying process of Hami melon slices.

Polarimetric method of generating full Poincaré beams within a finite extent.

A novel polarimetric method of generating a variety of Poincaré beams such as half Poincaré beams and full Poincaré beams using doubly inhomogeneous wave plates (d-plates) is proposed. In this method, every input state of polarization (SoP) through such a d-plate generates a unique Poincaré beam, thereby giving access to a potentially infinite number of them. Furthermore, the generation of full Poincaré beams is presented here as an instance of the geometrical problem of mapping the surface of a sphere onto a plane, and this insight allows one to design d-plates that convert the input SoP to every possible SoP, within a finite region of the beam. A gadget composed of three singly inhomogeneous wave plates for an equivalent realization of these d-plates is also presented.

Anesthetic management of women with heart failure during pregnancy: a retrospective cohort study.

BACKGROUND: The incidence of heart failure among pregnant women with pre-existing cardiac disease is quoted as 13%, with 10% requiring hospitalization. There is limited literature on heart failure in the pregnant population. The study objective was to describe the etiology and management of women hospitalized in our institution for heart failure during pregnancy. METHODS: A retrospective cohort study investigated women who presented with heart failure in pregnancy between 2004 and 2017. Hospital records were interrogated using International Classification of Diseases v10 codes for heart failure. Patient characteristics, investigations, treatment, obstetric and anesthetic management, and maternal-fetal outcome data were collected and summarized using descriptive statistics. RESULTS: One-hundred-and-twenty cases (in 93 122 deliveries) were identified across the 13-year period (antepartum heart failure 51%, postpartum heart failure 49%).The most common etiologies were pre-eclampsia (28%), cardiomyopathy (22%), and valvular heart disease (18%). Cesarean delivery occurred in 76% of cases (13% because of the maternal cardiac condition). Neuraxial techniques were used for most deliveries (cesarean 83%; vaginal 90%). For cesarean delivery, titrated epidural or general anesthesia was employed in 48% and 16%, respectively. Cardiac arrest occurred in two cases (1.7%) and 44% required coronary or intensive care unit admission. CONCLUSIONS: The incidence of heart failure was 0.13% (1:776 deliveries). Pre-eclampsia was the leading cause but may have been historically under-acknowledged. Anesthetic and obstetrical decisions were tailored by means of multidisciplinary input, with cesarean delivery and regional anesthesia used in the majority. The postpartum period warrants heightened attention for these patients.

Color and molecular structure alterations of brazilein extracted from Caesalpinia sappan L. under different pH and heating conditions.

Brazilein extract from sappan wood (Caesalpinia sappan L.) has potential for use as natural food colorant since it has no unique flavor and taste. Although brazilein has long been applied in several traditional foods and beverages, information on its stability, which is of importance for practical application, is still limited. In this work, brazilein was isolated from sappan wood; its purity was confirmed by nuclear magnetic resonance spectroscopy. Relations between molecular structures and color as well as thermal stabilities of brazilein in aqueous solutions at pH 3, 7 and 9 were for the first time investigated. At the lowest pH, zero net-charge structure of brazilein, which exhibited yellow color, was predominantly found. The deprotonated and fully deprotonated structures of brazilein, which exhibited orange and red colors, respectively, were found when pH of the aqueous solutions increased. The forms of brazilein existing at the higher pH suffered extensive degradation upon heating, while the form existing at the lowest pH possessed higher stability. Heat-induced deprotonation and degradation were confirmed by UV-visible and Fourier-transform infrared spectra as well as losses of brazilein content.

Wavelength-adaptable effective q-plates with passively tunable retardance.

Wave retarders having spatially varying optical axes orientations, called q-plates are extremely efficient devices for converting spin to orbital angular momentum of light and for the generation of optical vortices. Most often, these plates are designed for a specific wavelength and have a homogeneous constant retardance. The present work provides a polarimetric approach for overcoming both these limitations. We theoretically propose and experimentally demonstrate q-plates with tunable retardance, employing a combination of only standard q-plates and waveplates. A clear prescription is provided for realizing wavelength indepedent q-plates for a desired retardance, with a potential for ultrafast switching. Apart from the potential commercial value of the proposed devices, our results may find applications in quantum communication protocols, astronomical coronography, angular momentum sorting and in schemes that leverage optical vortices and spin to orbital angular momentum conversion.

Optimization of the proportions of four wastewaters in a blend for the cultivation of microalgae using a mixture design.

A 2nd degree mixture design was used to determine the optimal blend prepared from four wastewater streams to produce microalgae-based biomass. The streams consisted of a liquid digestate from an anaerobic digestion process, a landfill leachate, a septic-system sludge treatment plant liquid, and a wastewater treatment plant effluent. The mixture regression analysis indicated that blends with higher proportions of treated effluent and digestate improved cells growth, while the use of leachate was detrimental to the growth. The global solution of the mixture optimization predicted a maximum value of biomass productivity of 22.76 mg L-1 d-1, in a blend consisting of 19% treated effluent, 21% digestate, and 60% water. Proportions of leachate higher than 13.33% were detrimental to the growth. The concentration of ammonia-N in the blends ranged from 0.39 to 150 mg L-1 d-1, and its toxicity effect on the cells diminished with increasing amounts of organic carbon in the cultivation medium.

Fano resonance between coherent acoustic phonon oscillations and electronic states near the bandgap of photoexcited GaAs.

Impulsive photo-excitation of solids results in a travelling strain pulse which manifests itself as coherent acoustic phonon oscillations. These oscillations have been extensively studied using time-resolved pump-probe spectroscopy. In the present work, we report the generation of extremely long-lived, coherent longitudinal acoustic phonon oscillations in intrinsic GaAs (100), with clear and unambiguous evidence of Fano interference between these oscillations and the continuum of electronic states close to the bandgap. Fano resonance is a widespread phenomenon observed in atomic systems and condensed media that arises from quantum interference between a continuum of quantum states and a discrete quantum state. Among other techniques, Fano resonance has been investigated with respect to optical phonons studied with Raman Spectroscopy. In the present work, we investigate Fano resonance in coherent phonon oscillations generated without the aid of any capping layer, dopants or substrate/interface effects. Since Fano resonance is sensitive to changes in electronic structure, doping and defects, these observations are important to the field of picosecond ultrasonics which is used for non-destructive depth profiling of solids and for carrier diffusion studies.

High-humidity hot air impingement blanching alters texture, cell-wall polysaccharides, water status and distribution of seedless grape.

Blanching pretreatment plays an essential role in fruits and vegetables processing to obtain excellent final products. The purpose of current work was to characterise the texture, cell-wall polysaccharides and water distribution of grapes pre- and post- high-humidity hot air impingement blanching (HHAIB). The cell-wall pectins nanostructure, water status and distribution of samples were determined by atomic force microscopy (AFM), low field nuclear magnetic resonance (LF-NMR) and magnetic resonance image (MRI), respectively. Results revealed that blanching caused significant berry tissue softening which was accompanied by an increase of water-soluble pectin (WSP, from 39.57 to 57.44 g/100 g fresh weight) and a decrease of chelate-soluble pectin (CSP, from 79.34 to 53.78 g/100 g fresh weight) and sodium-carbonate-soluble pectin (NSP, from 364.23 to 187.64 g/100 g fresh weight) concentration. Obvious depolymerization and degradation was observed in cell-wall polysaccharides nanostructure in blanched berries. The length frequencies of WSP chains are mainly distributed in the range of 0.51-2.00 µm, while it was 1.01-2.00 µm for the CSP chains of blanched samples. LF-NMR transverse relaxation time and MRI analysis indicated that HHAIB treatment resulted in a water loss and migration from berry interior to surface tissue. The findings in present study provide a deeper understanding in tissue softening and moisture variation of blanched berries.

Optimization and characterization of hydrochar produced from microwave hydrothermal carbonization of fish waste.

Fish processing results in large amounts of solid and liquid wastes that are unsustainably dumped into oceans and landfills. Alternative sustainable technologies that completely utilize seafood wastes are needed. Hydrothermal carbonization (HTC) that converts moisture-rich biomass into hydrochar is mostly employed for pure lignocellulosic biowaste. However, the suitability of HTC for pure non-lignocellulosic waste is unknown. Here, for the first time, a response surface design guided optimization of microwave hydrothermal carbonization (MHTC) process parameters, holding temperature (150-210°C) and time (90-120min), showed that a temperature of approximately 200°C and a time of approximately 119min yielded maximal hydrochar (∼34%). The atomic carbon and ash content, and calorific value of hydrochar were approximately 25-57%, 20-28%, and 19-24.5MJ/kg respectively, depending on the MHTC operating conditions. Taken together, these results confirm that MHTC produces hydrochar from fish waste of quality comparable to one produced from certain lignocellulosic, sewage and municipal wastes. Therefore, this strategy presents an exciting alternative technology that can be used either independently or in combination with other valorization techniques to completely utilize fish wastes irrespective of their quality.

Effect of C/N ratio and salinity on power generation in compost microbial fuel cells.

In this work, compost Microbial Fuel Cells (cMFCs) were used to generate electricity from a mix of fruit and vegetable wastes, and soil with different C/N ratios and salinities. Experiments were carried out in 500mL cMFCs equipped with carbon felt anodes and manganese dioxide cathodes. The cMFCs were loaded with fresh compost and operated at 20-23°C for up to 97days. The low C/N ratio (C/N 24) had a greater power production with a maximum power density of 5.29mW/m(2) (71.43mW/m(3)), indicating a more favorable condition for microbial growth. High-saline cMFCs produced lower power, suggesting that their level of salinity (10g/L of NaCl) inhibited electricigenic microorganisms. The closed-circuit cMFC showed an improved degradation of organic matter by 6% to 8% compared to the control MFC operated in an open circuit mode (no external resistor attached).

Enhancing shelf life of minimally processed multiplier onion using silicone membrane.

The aim of storage of minimal processed product is to increase the shelf life and thereby extend the period of availability of minimally processed produce. The silicone membrane makes use of the ability of polymer to permit selective passage of gases at different rates according to their physical and chemical properties. Here, the product stored maintains its own atmosphere by the combined effects of respiration process of the commodity and the diffusion rate through the membrane. A study was undertaken to enhance the shelf life of minimally processed multiplier onion with silicone membrane. The respiration activity was recorded at a temperature of 30 ± 2 °C (RH = 60 %) and 5 ± 1 °C (RH = 90 %). The respiration was found to be 23.4, 15.6, 10 mg CO2kg(-1)h(-1) at 5 ± 1 °C and 140, 110, 60 mg CO2kg(-1) h(-1) at 30 ± 2° for the peeled, sliced and diced multiplier onion, respectively. The respiration rate for the fresh multiplier onion was recorded to be 5, 10 mg CO2kg(-1) h(-1) at 5 ± 1 °C and 30 ± 1 ° C, respectively. Based on the shelf life studies and on the sensory evaluation, it was found that only the peeled multiplier onion could be stored. The sliced and diced multiplier onion did not have the required shelf life. The shelf life of the multiplier onion in the peel form could be increased from 4-5 days to 14 days by using the combined effect of silicone membrane (6 cm(2)/kg) and low temperature (5 ± 1 °C).

Ohmic heating as a pre-treatment in solvent extraction of rice bran.

Rice bran, which is one of the major by products of paddy contain high quality proteins and edible oil apart from fibre, ash and NFE (nitrogen free extract). The existing solvent extraction method employs n-hexane as the most viable solvent for the extraction of oil from rice bran. But the high cost and scarce availability of n-hexane resulted in uneconomical extraction of rice bran oil. In this study, rice bran was ohmically heated for different time periods(1, 2 and 3 min) with different current values (5, 15 and 20 A) and with different concentration of sodium chloride (1 M, 0.1 M and 0.01 M) as conducting medium. The ohmically heated rice bran was subjected to extraction studies. Ohmic heating of rice bran of paddy varieties Red Triveni and Basmati reduced the extraction time by nearly 75 % and 70 % respectively and gave a maximum quantity of oil extracted when compared to bran, which was not ohmically heated. From the experiments with varying concentrations, residence time of ohmic heating and currents, it was found that ohmically heating the rice bran with 1 M sodium chloride solution and with a current value of 20 A for 3 min gave maximum oil extraction with minimum extraction time.

Physico-chemical changes in tomato with modified atmosphere storage and UV treatment.

Physico-chemical changes in ripe tomato (Lycopersicon esculentum Mill.) were analyzed on day 0 and 2 weeks after ultraviolet-C (UV-C) light treatment or modified atmosphere (MA) storage and combined UV-C + MA storage at 10 °C. Modified atmosphere packaging (MAP) film was used to create MA conditions. The tomatoes were evaluated for surface colour, mass loss, firmness, respiration rate, total soluble solids and antioxidant capacity. The tomatoes treated with UV-C and MA storage underwent least changes in their physico-chemical properties, indicating that combination of UV-C and MA storage was successful in retaining the attributes of the fresh product. The increase in antioxidant capacity of the tomatoes during UV-C treatment suggested that UV treatment during post harvest handling may be successfully combined with MA storage, resulting in a product with better nutritive value.

The "leicester lasso" lateral canthoplasty.

PURPOSE: To describe an innovative technique of lateral canthal tendon (LCT) anchoring to the lateral orbital rim on its inner aspect using a "lasso" technique, in order to provide the ideal vector. METHODS: A retrospective case review of seven patients (n = 7), performed from 2009 to 2013 at our institution by the senior author (RGS). RESULTS: Excellent results in all cases with optimal restoration of form and function. CONCLUSIONS: The 'Leicester Lasso' technique is a safer technique of securing the LCT to the orbital rim.

Effect of high-pressure on calorimetric, rheological and dielectric properties of selected starch dispersions.

Effects of high-pressure (HP) treatment on the rheological, thermal and dielectric properties of the four selected starch dispersions (two modified starches, one native and one resistant) were evaluated. Differential scanning calorimetry (DSC) and oscillatory rheometry were employed to assess the extent of starch gelatinization and the developed gel rigidity (G') of starch gels after HP treatment. It was observed that starch dispersions gelatinized completely at 500 MPa with a 30-min holding time. The HP-treated starch samples exhibited predominantly solid-like (G'>G") behavior except for the resistant starch. Pressure-induced gel rigidity differed significantly among starch samples. The G' of starch gels increased with the pressure (400-600 MPa) in the studied frequency range (0.1-10 Hz) except for the native starch where a marginal decrease was recorded at similar condition. The holding time (15-30 min) and concentration (20-25% w/w) significantly attributed towards gel rigidity of starch samples. Measurement of dielectric properties of HP-treated samples over the frequency range 450-4450 MHz indicated differences in the dielectric constant (ɛ'), loss factor (ɛ") and penetration depth among starch gels. Pressure did not show any effect on dielectric property of the resistant starch sample. Power penetration depth decreased significantly with frequency and with the pressure.

A prospective, multicentre study of malignant and premalignant lesions at the base of periocular cutaneous horns.

PURPOSE: The primary objective of the study was to determine the incidence of the various pathological conditions present at the base of the periocular cutaneous horns. The secondary objective was to study the presentation of these cutaneous horns with a view to finding any clinical indicators for premalignant, malignant and benign lesions at the base. METHODS: Prospective multicentre study of patients presenting with cutaneous horns. Informed consent followed by excision biopsy of the base lesion was performed in all the cases included for the study. The biopsy specimens were examined histologically and results analysed. RESULTS: Twenty-six patients presented with cutaneous horns in the periocular region over a period of 2 years, of these two patients presented with more than one cutaneous horn. 23 patients underwent excision biopsy. There were a total of 25 specimens. Of the base lesions 2/25 (8%) were malignant, 7/25 (28%) were pre-malignant and the remaining 16/25 (64%) were benign. Analysis of the findings on clinical presentation revealed no clinical indicators to correlate with the final histology. CONCLUSION: The incidence of malignant and pre-malignant lesions present at the base of periocular cutaneous horns was 36% with 8% of them being malignant. It is important to perform an excision biopsy with histological diagnosis of the base of the cutaneous horn as there are no definite clinical features that point towards a potential for malignancy.

Microwave-assisted extraction of phenolic antioxidants from potato peels.

A response surface method was used to optimize the microwave-assisted extraction parameters such as extraction time (t) (min), solvent (methanol) concentration (S) (v/v) and microwave power level (MP) for extraction of antioxidants from potato peels. Max. total phenolics content of 3.94 mg g⁻¹ dry weight (dw) was obtained at S of 67.33%, t of 15 min and a MP of 14.67%. For ascorbic acid (1.44 mg g⁻¹ dw), caffeic acid (1.33 mg g⁻¹ dw), ferulic acid (0.50 mg g⁻¹ dw) max contents were obtained at S of 100%, t of 15 min, and MP of 10%, while the max chlorogenic acid content (1.35 mg g⁻¹ dw) was obtained at S of 100%, t of 5 min, and MP of 10%. The radical scavenging activity of the extract was evaluated by using the DPPH assay and optimum antioxidant activity was obtained at S of 100%, t of 5 min, and MP of 10%.

Visualization of microwave energy distribution in a multimode microwave cavity using CoCl2 on gypsum plates.

This study provides a facile method to map the microwave field distribution in a multimode microwave cavity. Anhydrous calcium sulfate powder was used to make the gypsum plates that were used as the carrying medium. Cobalt chloride hexahydrate, whose color changes when losing part or all of its crystal waters, was selected as an indicator of the energy absorption. The cobalt chloride aqueous solution at a concentration of 1.6% was absorbed by the dried gypsum plates. After introducing the plates into a microwave field, those areas that receive more microwave energy were preferably heated, resulting in the release of the moisture and consequently the loss of crystal water from the cobalt chloride hexahydrate. The color change on the plate formed a color map indicating the microwave field distribution. This method was used to investigate the energy distribution of a microwave oven by placing single or multiple plates in horizontal or vertical positions at different locations in the cavity.