Biosystems Engineering Research Articles

Prospects and Challenges of Pyrolysis Technologies for Biomass Conversion

Prospects and Challenges of Pyrolysis Technologies for Biomass Conversion

Production and quality of mini watermelon cv. Smile irrigated with saline water

ABSTRACT The purpose of this study was to evaluate the salt tolerance of mini watermelon (cv. Smile). The experiment was carried out in the greenhouse of the Department of Biosystems Engineering of ESALQ/USP. The experimental design was randomized blocks. The plants were irrigated with five levels of salinity (S1 = 1.0; S2 = 2.0; S3 = 3.0; S4 = 4.0 and S5 = 5.0 dS m-1). At 85 days after the beginning of the experiment, the plants and the physical and chemical variables of the fruit were evaluated. Salinity negatively affected the variables: length of the main stem, stem diameter, number of leaves, number of branches, leaf area, fresh and dry matter. Regarding the physical and chemical characteristics of fruits, salinity reduced the mass, diameter and the pH of the fruit, but increased its vitamin C content. In general, the results suggest that the mini watermelon (cv. Smile) is moderately sensitive to salinity.

Performance of LAI-2200 Plant Canopy Analyzer on Leaf Area Index of Jatropha Nut Estimation

Leaf Area Index (LAI) of crops can be determined by many different methodologies with direct or indirect measurements. The use of sensors to estimate LAI has the advantage of fast and easy measurements, however, it is necessary to test and calibrate in order to verify its reliability. The objective of this study was to test and calibrate the LAI-2200 plant canopy analyzer on the estimative of LAI of jatropha nut trees. Methodology: The study was conducted in the experimental area of Biosystem Engineering, Department of ESALQ/USP, in Piracicaba, Sao Paulo, Brazil. The test was performed with 9 jatropha nut plants, by comparing estimated LAI data with LAI-2200 equipment with real LAI by destructive sampling. Results: The isolate plant measurement overestimated around 30% of real LAI and the pattern measurements underestimated around 10%. Conclusion: Both models were considered adequate according to the statistical parameters results and they can be used to correct estimated LAI in order to present better result of LAI for jatropha nut.

Multi‐objective optimization of transesterification in biodiesel production catalyzed by immobilized lipase

AbstractIn order to comply with criteria of green energy concepts and sustainability, a multi‐objective analysis was performed for the transesterification of waste cooking oil (WCO) using immobilized lipase. Response surface methodology and artificial neural networks, followed by multiple response optimization through a desirability function approach were applied to individually and simultaneously evaluate the fatty acid methyl esters (FAME) content and the exergy efficiency. Reaction time and concentrations of methanol, immobilized lipase and water were considered as the design variables in maximizing FAME content and exergy efficiency. The maximum individual desirability of FAME content was predicted to be 95.7% corresponding to a methanol to WCO molar ratio of 6.7, catalyst concentration of 45%, water content of 9% and reaction time of 25 h. However, based on the simultaneously optimization of both the FAME content and the exergy efficiency, the maximum overall desirability was found at a methanol to WCO molar ratio of 6.7, catalyst concentration of 35%, water content of 12% and reaction time of 20 h to achieve FAME content of 88.6% and exergy efficiency of 80.1%, respectively. © 2016 Society of Chemical Industry and John Wiley & Sons, Ltd

A Closer Look: Stream Geomorphology and Ecohydrological Interactions in the Minnesota River Basin

A Closer Look: Stream Geomorphology and Ecohydrological Interactions in the Minnesota River Basin

English

In sugar cane crop fertigation management systems, about 500 m3 ha-1 of diluted vinasse is applied annually by cycle, promoting nutrient recycling and supply to the soil, especially that of potassium (K). With the increase of sugar cane areas with subsurface drip irrigation, hydraulic characterization related to vinasse intermittent application is important, in order to verify uniformity flow in drippers. The aim of this study was to hydraulically characterize performance and orifice position of different dripline models subjected to intermittent vinasse application, in order to verify flow disorders. The experiment conducted was in a test bench in the Biosystem Engineering Department - ESALQ/USP. The experimental design was completely randomized, with 10 repetitions. Four dripline models (Hydrolite HY 0.65, Hydrolite HY 1.0, Drip Net PC DN 0.6 and Drip Net PC DN 1.6) and 13 consecutive weekly assessment periods were used as treatments. At the same time, dripline orifice position influence (upward and downward) was assessed in two (Hydrolite HY 0.65 and Drip Net PC DN 0.6) of the four dripline models in the respective periods (2x2x13 factorial = Two models, two orifice positions and 13 periods/weeks). Ten drippers from each model were randomly selected, in order to monitor flow. Vinasse application was conducted daily during four hours, with dripline product rest for 20 h, and flow reading at every 168 test h (weekly). HY models (0.65 L h-1) with drippers positioned upwards and downwards, and upwards HY (1.0 L h-1) and DN (1.6 L h-1) showed flow variation coefficient (VC) lower than 5%, which is rated as excellent. The other models showed VC lower than 10%, which was classified as good, enabling vinasse use in the 2:1 concentration in driplines. Key words: Flow variation coefficient. clogging. fertigation. dripping. potassium. vinasse.

MONITORAMENTO DA CONDUTIVIDADE ELÉTRICA E PH DA SOLUÇÃO DO SOLO SOB DIFERENTES DOSES DE APLICAÇÃO DE VINHAÇA - DOI: 10.13083/1414-3984/reveng.v23n6p552-561

Objetivou-se, neste trabalho, avaliar a condutividade elétrica (CEs) e o pH da solução do solo cultivado com abacaxi Vitória e fertirrigado com vinhaça, de modo a suprir 0, 50, 75, 100 e 125% da recomendação de potássio para essa cultura, obtendo-se, dessa forma, os seguintes tratamentos: T1 – 0 m³ ha-¹; T2 – 231 m³ ha-¹; T3 – 347 m³ ha-¹; T4 – 462 m³ ha-¹; T5 – 578 m³ ha-¹. O experimento foi conduzido em casa de vegetação no Departamento de Engenharia de Biossistemas da ESALQ/USP. O plantio foi realizado em trincheiras abertas ao nível do solo totalmente revestidas com lona e preenchidas com solo classificado como Latossolo Vermelho Amarelo. As aplicações de vinhaça foram realizadas quinzenalmente por meio de fertirrigação utilizando sistema de irrigação por gotejamento. Foram instalados extratores nas profundidades de 0,20 m e 0,40 m e, para extração da solução, aplicou-se vácuo na tensão de 60 kPa, duas horas após o término da fertirrigação. A coleta da solução foi realizada aos 30, 120, 210 e 270 dias após início dos tratamentos. Verificou-se que os tratamentos com aplicação de vinhaça apresentaram os maiores valores de CEs nas camadas superficiais do solo. Os resultados revelaram que o pH diminui à medida em que se aumentou os volumes de vinhaça aplicados.

Report on the 44th International Symposium: Actual Tasks on Agricultural Engineering, 23rd-26th February 2016, Opatija, Croatia

The 44<sup>th</sup> International Symposium <em>Actual Tasks on Agricultural Engineering</em> was held on 23<sup>rd</sup>-26<sup>th</sup> February 2016 in Grand Hotel <em>Adriatic</em> Opatija, Republic of Croatia. The principle Organiser, Agricultural Engineering Department, Faculty of Agriculture, University of Zagreb was supported by the following frameworks: Department of Agricultural Engineering, Faculty of Agriculture, University J.J. Strossmayer, Osijek, Department of Bio-systems Engineering, Faculty of Agriculture and Lifesciences, University of Maribor (Slovenia), Agricultural Institute of Slovenia, National institute for agricultural machinery - INMA Bucharest (Romania) and Croatian Agricultural Engineering Society. In addition, CIGR, EurAgEng and AAAE bestowed their support and endorsement on the Event.

Biosystems Engineering of Prokaryotes with Tumor-Killing Capacities.

Certain bacteria selectively attack tumor tissues and trigger tumor shrinkage by producing toxins and modulating the local immune system, but their clinical utility is limited because of the dangers posed by systemic infection. Genetic engineering can be used to minimize the risks associated with tumor-targeting pathogens, as well as to increase their efficiency in killing tumor cells. Advances in genetic circuit design have led to the development of bacterial strains with enhanced tumor-targeting capacities and the ability to secrete therapeutics, cytotoxic proteins and prodrug-cleaving enzymes, which allows their safe and effective use for cancer treatment. The present review details the recent advances in the design and application of these modified bacterial strains.

Optimizing Spike-Sorting Yield through Selection of Optimal Recording Sites in High-density Microelectrode Arrays

Optimizing Spike-Sorting Yield through Selection of Optimal Recording Sites in High-density Microelectrode Arrays

Dual-mode-operation Microelectrode Array for Extracellular Action Potential Recording

Event Abstract Back to Event Dual-mode-operation Microelectrode Array for Extracellular Action Potential Recording Xinyue Yuan1*, Sungho Kim2, Michele D’Urbino2, Julien Juyon2, Marie E. J. Obien1, Torsten Bullmann2, Yihui Chen1, Alexander Stettler3, Andreas Hierlemann4 and Urs Frey4 1 ETH Zurich, Department of Biosystems Science and Engineering, Switzerland 2 Riken, Quantitative Biology Center, Japan 3 ETH Zurich, Department of Biosystems Science and Engineering, Switzerland 4 ETH Zurich, Department of Biosystems Science and Engineering, Switzerland Motivation A variety of readout schemes has been demonstrated for CMOS-based high-density microelectrode arrays (HDMEA), each featuring advantages and disadvantages [1]. Active-pixel sensor (APS) arrays, for example, enable simultaneous recording from thousands of electrodes but with sub-optimal SNR, while switch-matrix (SM) devices enable recording at best possible SNR, whereas only a subset of electrodes can be recorded from simultaneously. Here, a dual-mode operation MEA (DM-MEA) is presented with the aim to leverage the advantages of APS and SM arrays by realizing a combined architecture. We developed a specific reconstruction algorithm to process the raw data acquired by the APS readout. For many experiments, especially studies of neuronal network activity, the DM-MEA is an enabling technology, since it provides high throughput and high SNR at the same time. An example would be the study of the propagation of action potentials on full axonal arbors. Material and Methods The array is composed of 96×96 pixels with an electrode density of 3050 mm-2. Pt electrodes were fabricated through post-processing, using a previously published shifted-electrode design [2]. For APS, there are 9216 readout channels with a frame rate of 6.5 kHz, while the SM readout includes 112 channels at a sampling rate of 20 kHz. Results The DM-MEA has been fabricated and tested [3]. Measured noise levels were 11.1 µVrms for APS and 1.6 µVrms for SM mode (spike sorting potential band, 300 Hz – 5 kHz) at a power consumption of 3.3 µW (APS) and 38.1 µW (SM) per channel. Experiments have been done with cerebellar acute slices and cultured neuron cells using SM and APS readout simultaneously. Conclusion The concept of a DM-MEA is presented. Owing to its flexibility in choosing readout modes and stimulation routings, the DM-MEA is a versatile tool that is applicable to various neuroscience studies with a broad range of requirements.

UnitBrowser - A Tool to Evaluate and Post-Process Units Sorted by Automatic Spike Sorting Algorithms

UnitBrowser - A Tool to Evaluate and Post-Process Units Sorted by Automatic Spike Sorting Algorithms

Highly Matched TO Pseudo-resistors for Multi-channel Neural Signal Recording Applications

Event Abstract Back to Event Highly Matched TΩ Pseudo-resistors for Multi-channel Neural Signal Recording Applications Vijay Viswam1*, Yihui Chen2, Raziyeh Bounik2, Amir Shadmani1, Jelena Dragas2, Jan Müller2 and Andreas Hierlemann2 1 ETH Zürich, Department of Biosystems Science and Engineering, Switzerland 2 ETH Zurich, Department of Biosystems Science and Engineering, Switzerland Motivation To reduce drift and offset of electrodes, neural amplifiers usually employ high pass filters with very low corner frequencies (e.g., fHPF<10Hz). This approach requires huge on-chip resistances (~T½). To keep the silicon area small, "pseudo-resistors" (MOS transistors biased in the weak inversion region) are frequently used [1], but their resistance may considerably vary due to processing and fabrication spread, temperature fluctuations, and even different locations on the same chip may feature different properties. Here, specific new pseudo-resistor structures have been devised to achieve small fHPF variations. Material and Methods The new pseudo-resistors were implemented in a CMOS high-density MEA system incorporating 2048 readout channels [2]. Two different kinds of pseudo-resistor topologies were devised. For the 1st stage, open-loop amplifiers were used, while, for the 2nd stage closed-loop amplifiers were implemented. Aided by the current mirrors and level shifters, the first-order dependence of the overdrive voltages of the transistors inside RPR1 and RPR2 on their threshold voltages was cancelled out. Thus, RPR1 and RPR2 variations were substantially reduced, which lead to small fHPF variations. A wide range of resistances could also be realized by changing the bias currents, which could be digitally tuned with 7-bit current DACs implemented on-chip. Results High pass filter corner frequency (fHPF) of the the neural amplifiers tuned by pseudo-resistors were measured. The uniformity of fHPF showed the inter-channel matching of pseudo resistors across 2048 channels in the high and low frequency range. Conclusions Current-biased pseudo-resistors for neural signal recording applications are introduced in this work. The two new structures enable to realize very large resistances while keeping the silicon area small. Results on the transfer function of the neural amplifiers and the matching of the pseudo-resistors have been shown in this paper. The circuits were fabricated in 180nm 6M1P CMOS technology.

Long-term High-density Microelectrode Array Recordings Evidence Stability of Neuron Locations in Organotypic Hippocampus Slices

Long-term High-density Microelectrode Array Recordings Evidence Stability of Neuron Locations in Organotypic Hippocampus Slices

Study of breast cancer metastasis in vitro using a 3D tissue scaffold

Event Abstract Back to Event Study of breast cancer metastasis in vitro using a 3D tissue scaffold Gowri Balachander1, Sai A. Balaji2, Annapoorni Rangarajan1, 2 and Kaushik Chatterjee1, 3 1 Indian Institute of Science, Centre for Biosystems Science and Engineering, India 2 Indian Institute of Science, Department of Molecular Reproduction Development and Genetics, India 3 Indian Institute of Science, Department of Materials Engineering, India Introduction: Breast cancer is the most common cause of cancer related deaths in women worldwide and metastasis accounts the vast majority of such deaths[1]. Metastasis is a multi-step process wherein the cancer cells migrate from the primary tumor into the vasculature, survive in the circulation, extravasate into the secondary site and establish a tumor[2]. Understanding the molecular mechanisms that orchestrate metastasis provide useful insights into developing therapeutics that prevent or treat metastasis. While conventional two-dimensional (2D) cell culture systems fail to mimic in vivo signaling due to the planar architecture and inappropriate substrate stiffness[3], animal based xenograft models are expensive and time consuming. To overcome these drawbacks, three dimensional (3D) scaffold based models are being developed which help recapitulate the in vivo tissue micro-environment. In this study, for the first time, we have developed a comprehensive in vitro model to study the events in breast cancer metastasis using a 3D scaffold of polycaprolcatone (PCL). Materials and Methods: Macro-porous scaffolds of PCL were prepared by salt leaching with a pore size of 250-400 µm. MDA-MB-231, a transformed metastatic breast cancer cell line was cultured on the PCL scaffolds and compared to cells cultured on conventional 2D TCPS dishes. Gene expression was scored using quantitative Real Time PCR. Protein expression was assayed using immuno-fluorescence. Functional assays like invasion and sphere formation in methyl cellulose were performed to assess the invasion potential and cancer stem cell activity. In vivo tumorigenicity and metastatic potential were assayed. Global gene expression changes were analyzed using whole genome gene expression microarrays. Results and Discussion: 3D porous PCL scaffolds were fabricated to mimic the mechanical properties of the breast tissue. The topography of the scaffold mimicked the acinar architecture and the elastic modulus was 7.5 kPa, comparable to that of the breast tumor[4]. MDA-MB-231 cells cultured on the scaffolds formed a 3D cell-cell contacts which on prolonged culture gave rise to tumoroids. Scaffold cultured cells had higher expression of genes like TWIST1, Vimentin, Nanog, Oct3/4, CD44, Fibronectin, Gli2 and PTHrP which are implicated in initiation, progression and colonization of the metastasis cascade. Functional assays showed increased invasion and sphere formation in scaffold cultured cells compared to cells grown in control dishes. The scaffold cultured cells exhibited increased tumor formation ability and increased lung metastasis in NOD/SCID mice, suggesting that culturing cells on PCL scaffolds increased their metastatic potential compared to culturing on conventional TCPS dishes. Microarray based whole genome transcript analysis also supported the qRT PCR data and indicated a profound increase in cell-cell and cell-matrix interactions in the scaffold cultured cells. Also the analysis revealed that these cells had a strong pro-inflammatory gene expression signature which could play an important role in tumor-stroma interactions and tumor metastasis. Conclusion: 3D PCL scaffolds can be used for culture of breast cancer cells to mimic many of the molecular events of breast cancer metastasis in contrast to cells on conventional culture plates. The cells in scaffolds exhibit enhanced metastatic potential in vitro which resulted in more potent tumor in vivo. Acknowledgement: We thank the Council for Scientific and Industrial Research (CSIR), India, for funding KC for this work. Figure 1: SEM micrographs of MDA-MB-231 cells in 2D TCPS (A) and in 3D scaffolds cultured for 7 (B) and 14 days (C). Yellow arrows indicate inter-cellular contacts. Tumoroid mass formed by MDA-MB-231 cells on culture for 14 days indicated by red arrows. Fluorescence images of MDA-MB-231 cells in 2D TCPS (D) and in 3D scaffolds cultured for 7 (E) and 14 days (F) stained for actin (red) and nucleus (green). Scale bars represent 50 microns. Figure 2: Live animal imaging of tumors formed by MDA-MB-231 cells from control TCPS dishes and from 3D PCL scaffolds (SDT) in NOD-SCID mice.

Experimental analysis of effect of electric field on mouse myoblast cells using high throughput microfluidic bioreactor

Event Abstract Back to Event Experimental analysis of effect of electric field on mouse myoblast cells using high throughput microfluidic bioreactor Sharmistha Naskar1, Bikramjit Basu1, 2 and V Kumaran1, 3 1 Indian Institute of Science, Centre for Biosystems Science and Engineering (BSSE), India 2 Indian Institute of Science, Materials Research Centre, India 3 Indian Institute of Science, Department of Chemical Engineering, India Application of electric field on excitable cells like myoblast[1] or neuroblast[2], causes cell phenotype changes which have already been investigated using conventional 2D cell culture. But this may not be a good representation of the in vivo conditions due to very high ratio of volume of culture media to the number of cells and also due to absence of the shear stress in comparison to in vivo conditions where cells continuously experience fluid flow around them. In this study, we had attempted to investigate the effect of electric field on the cells by introducing biomimetic devices that simulates the in vivo environment, using microfluidic technology. Microfluidics has already started to invade almost every corner of life sciences with the promise of more effective and efficient performance than the existing techniques with the requirement of very scanty amount of sample volume, reduction in the running cost of the experiments, high accuracy due to almost zero dead-volume and fast response time. In order to achieve an environment having close resemblance with the in vivo conditions, C2C12 (mouse myoblast) cells were cultured within the microfluidic bioreactor along with flow of culture media. Designing of this microfluidic bioreactor involved some crucial processes, including the microfluidic layout, selection of materials, fabrication process, and sterilization technique along with necessary requirements like the maintenance of sterility and biocompatibility. This microfluidic bioreactor was fabricated through photolithography by procuring a silicon based SU8 master. This SU8 master was used as a mold for device fabrication using Polydimethylsiloxane (PDMS). The C2C12 cells were then seeded inside the microfluidic channels (width of 20μm - 40μm) of the bioreactor device. By limiting both the space and nutrient for the cultured cells along with an exposure to shear stress due to flowing of fluid, this system provided a close resemblance with the in vivo scenarios. Prior exposure of mouse myoblast cells to an electric field of 12.5 V/cm for 12 hours resulted in morphological alterations with elongated nucleus, roughening of the cell suface topography, myogenesis, as revealed by immunofluorescence techniques, electron microscopy and PCR supported with biochemical assays. Overall, the results confirmed considerable morphological changes of the myoblasts, when stimulated electrically compared to the non-stimulated cells. Prof. Bikramjit Basu; Prof. V. Kumaran

Assessment of Connectivity in Neuronal Cultures by Recording from Axonal Arbors

Event Abstract Back to Event Assessment of Connectivity in Neuronal Cultures by Recording from Axonal Arbors Stefan Huber1*, Torsten Bullmann1, Kosmas Deligkaris1, Andreas Hierlemann2 and Urs Frey1 1 RIKEN , Quantitative Biology Center, Germany 2 ETH Zurich, Department of Biosystems Science and Engineering, Switzerland Motivation A key problem in neuroscience is to understand the relationship between structure and function. Here, we present a novel method that estimates the morphological connectivity and compares it to a measure of functional connectivity. Material and Methods Dissociated neurons from E16-18 rat neocortex were cultured at low density on high-density microelectrode arrays (HDMEAs, Frey et al., 2010). After identification of axon initial segments, network activity was recorded, and action potentials were tracked along full axonal arbors of single neurons at subcellular resolution. Morphological connectivity was estimated according to Peter's rule from the overlap of axonal and dendritic fields, using parameters for the dendritic field diameter and the minimum overlap area ratio. Functional connectivity was assumed, when the ISI histograms showed a clear peak (z-score>25) as compared to randomized surrogate data. Results We developed a python library (PyTau) with fast implementation of procedures to calculate and visualize morphological and functional connectivity in neuronal networks based on HDMEA recordings. Furthermore, we observed a high correlation of inferred delay values between neurons. Discussion Since in this study only 25 neurons and their respective axonal arbors were analyzed, there remain many neurons in the recorded network unknown. Newer generations of HDMEAs with a larger number of parallel readout channels will make it possible to essentially record from all neurons so that the whole neuronal network can be assessed. Conclusion Although preliminary results were obtained on a small network with many hidden units, our method can easily be scaled to handle large datasets, which enables a comprehensive analysis of neuronal cultures including morphology, connectivity and activity. We have applied this method to study the effects of temperature on sleep and memory in vitro (Bullmann et al., 2016). References Bullmann, T. et al. 2016. 10th international Meeting on Substrate-integrated Microelectrode Arrays, Reutlingen, Germany. Frey, U. et al. 2010. IEEE Journal of Solid-State Circuits 45(2): 467–482. Figure 1 Inferred morphological connectivity. Axonal delay map (colorcoded green-yellow) and dendritic fields with r=100μm around the axon initial segment (grey circles, left panel) are used to infer connectivity. When their overlap exceeded 5%, a connection with axonal delay τAxon was assigned (right panel). Figure 1 Keywords: connectivity, axonal arbors, Peter's rule, spike time lag Conference: MEA Meeting 2016 | 10th International Meeting on Substrate-Integrated Electrode Arrays, Reutlingen, Germany, 28 Jun - 1 Jul, 2016. Presentation Type: Poster Presentation Topic: MEA Meeting 2016 Citation: Huber S, Bullmann T, Deligkaris K, Hierlemann A and Frey U (2016). Assessment of Connectivity in Neuronal Cultures by Recording from Axonal Arbors. Front. Neurosci. Conference Abstract: MEA Meeting 2016 | 10th International Meeting on Substrate-Integrated Electrode Arrays. doi: 10.3389/conf.fnins.2016.93.00077 Copyright: The abstracts in this collection have not been subject to any Frontiers peer review or checks, and are not endorsed by Frontiers. They are made available through the Frontiers publishing platform as a service to conference organizers and presenters. The copyright in the individual abstracts is owned by the author of each abstract or his/her employer unless otherwise stated. Each abstract, as well as the collection of abstracts, are published under a Creative Commons CC-BY 4.0 (attribution) licence (https://creativecommons.org/licenses/by/4.0/) and may thus be reproduced, translated, adapted and be the subject of derivative works provided the authors and Frontiers are attributed. For Frontiers’ terms and conditions please see https://www.frontiersin.org/legal/terms-and-conditions. Received: 22 Jun 2016; Published Online: 24 Jun 2016. * Correspondence: Dr. Stefan Huber, RIKEN, Quantitative Biology Center, Kobe, Germany, stefanhuber1993@googlemail.com Login Required This action requires you to be registered with Frontiers and logged in. To register or login click here. Abstract Info Abstract The Authors in Frontiers Stefan Huber Torsten Bullmann Kosmas Deligkaris Andreas Hierlemann Urs Frey Google Stefan Huber Torsten Bullmann Kosmas Deligkaris Andreas Hierlemann Urs Frey Google Scholar Stefan Huber Torsten Bullmann Kosmas Deligkaris Andreas Hierlemann Urs Frey PubMed Stefan Huber Torsten Bullmann Kosmas Deligkaris Andreas Hierlemann Urs Frey Related Article in Frontiers Google Scholar PubMed Abstract Close Back to top Javascript is disabled. Please enable Javascript in your browser settings in order to see all the content on this page.

Variations in the chemical composition of the solution extracted from a Latosol under fertigation with vinasse

The aim of this work was to evaluate the change in electrical conductivity and pH of a soil solution and its composition, with regard to the levels of nitrate and potassium, in a Latosol cultivated with pineapple and subjected to applications of different levels of vinasse. The experiment was conducted in a greenhouse at the Department of Biosystems Engineering of ESALQ/USP. The treatments comprised the application of five levels of vinasse: T1 - 0 m3 ha-1, T2 - 231 m3 ha-1, T3 - 347 m3 ha-1, T4 - 462 m3 ha-1, and T5 - 578 m3 ha-1. Application was every 20 days, using a localised irrigation system with emitters having a nominal flow rate of 4 L h-1 and spaced 0.40 m apart. The applied doses of vinasse were calculated by following the recommendations of CETESB standard P4.231, so that treatment T4 would supply the demand of the pineapple plant for potassium. The solution was collected by means of porous capsule extractors at 30, 120 and 210 days from the start of vinasse application. It was found that increases in the volume of the applied levels resulted in greater values for the electrical conductivity of the soil (ECs) and in the concentration of potassium (K) and nitrate (NO3), with higher values being obtained in the 0.20 m layer. The results demonstrated that pH decreased with increases in the vinasse being applied.

풀칠·고명기로 제조된 김부각의 물리적 건조 및 튀김 특성

Department of Rural and Biosystems Engineering, Chonnam National University, Gwangju 500-757, KoreaReceived on 11 September 2015, revised on 12 November 2015, accepted on 13 November 2015Abstract : Kimbugak is one of Korea’s traditional snacks made of laver. This study was conducted to investigate the physical drying and frying characteristics of kimbugaks made by a pasting & garnishing machine. The drying and frying characteristics should be analyzed to develop a continuous operation system for manufacturing kimbugak because kimbugak has a high moisture content after pasting process. Materials for pasting and garnishing on laver were rice gruel and sesame. The aluminum shelf with square hole was selected as a drying shelf. The recommended size of the square hole type was 1.5 mm × 1.5 mm because characteristics of deformation and easy separation from the shelf were excellent at the hole size. The drying time of 2 hours was also recommended with the drying temperature of 70℃ based on the test results such as dried condition (good), moisture conten t (3.7%), deformation (12.1 mm), and shrinkage rate (19.8%). As the frying conditions for dried kimbugaks, recommended oil temperature and frying time were 170℃, 15 seconds, respectively when corn oil was used. In the case of frying for undried kimbugaks, recommended oil temperature and frying time were 210℃, 2 - 3 minutes, respectively for improvement of work efficiency.Key words : Laver, Kimbugak, Drying & frying condition, Mechanical manufacturing, Physical characteristics*Corresponding author: Tel: +82-62-530-2157E-mail address: y-choi@jnu.ac.kr

Trends in Recent Studies on Post-Harvest Technology

Purpose: This article summarizes the trends in recent research publications in relation to post-harvest technology for drying, storage, and quality, between 2005 and 2015. Methods: As of S eptember 7, 2015, a s earch query using two keywords, drying and agriculture, on the Web of Science (Registered trademark of Thomson Reuters) resulted in 3749 articles that were published between 2005 and 2015. However, the review was restricted to research articles published in the journals Transactions of the ASABE (American Society of Agricultural and Biological Engineers) and Biosystems Engineering: Journal of European Agricultural Engineering. Results: The total number of articles in the two journals related to drying, storage, and quality was 500, 319, and 885, respectively. The number of articles related to drying, storage, and quality was 250, 177, and 250, respectively, in Transactions of the ASABE. The number of articles related to drying, storage, and quality was 250, 142, and 283, respectively, in Biosystems Engineering. Conclusions: A shift in research focus from drying and storage to quality in Transactions of the ASABE might reflect a shift toward quality-conscious consumers. It seems that ASABE members are more focused on articles related to post-harvest technologies on quality than their European counterparts. Articles were cited based on their abstract content. Readers should read the full articles for more details.