Search results for: fruit size
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 6226

Search results for: fruit size

4546 Amorphous Aluminophosphates: An Insight to the Changes in Structural Properties and Catalytic Activity by the Incorporation of Transition Metals

Authors: A. Hamza, H. Kathyayini, N. Nagaraju

Abstract:

Aluminophosphates, both amorphous and crystalline materials find applications as adsorbents, ceramics, and pigments and as catalysts/catalyst supports in organic fine chemical synthesis. Most of the applications are varied depending on the type of metal incorporated, particle size, surface area, porosity and morphology of aluminophosphate. The porous and surface properties of these materials are normally fine-tuned by adopting various preparation methodologies. Numerous crystalline microporous and mesoporous aluminophosphates and metal-aluminophosphates have been reported in literature, in which the synthesis has been carried out by using structure directing organic molecules/surfactants. In present work, amorphous aluminophosphate (AlP) and metal-aluminophosphates MAlP (M = Cu, Zn, Cr, Fe, Ce and Zr) and their mixed forms M-1M2AlP are prepared under a typical precipitation condition, i.e. at low temperature in order to keep the Von-Weirmann relative super saturation of the precipitating medium and obtain small size precipitate particles. These materials are prepared without using any surfactants. All materials are thoroughly characterised for surface and bulk properties by N2 adsorption-desorption technique, XRD, FT-IR, TG and SEM. The materials are also analysed for the amount and the strength of their surface acid sites, by NH3-TPD and CO2-TPD techniques respectively. All the materials prepared in the work are investigated for their catalytic activity in following applications in the synthesis of industrially important Jasminaldehyde via, aldol condensation of n-heptanal and benzaldehyde, in the synthesis of biologically important chalcones by Claisen-shmidth condensation of benzaldehyde and substituted chalcones. The effect of the amount of the catalysts, duration of the reaction, temperature of the reaction, molar ratio of the reactants has been studied. The porosity of pure aluminophosphate is found to be changed significantly by the incorporation of transition metals during preparation of aluminophosphate. The pore size increased from microporous to mesoporous and finally to macroporous by following order of metals Cu = Zn < Cr < Ce < Fe = Zr. The change in surface area and porosity of double metal-aluminophosphates depended on the concentration of both the metals. The acidity of aluminophosphate is either increased or decreased which depended on the type and valence of metals loaded. A good number of basic sites are created in metal-aluminophosphates irrespective of the metals used. A maximum catalytic activity for synthesis of both jasminaldehyde and chalcone is obtained by FeAlP as catalysts; these materials are characterized by decreased strength and concentration of acidic sites with optimum level basic sites.

Keywords: amorphous metal-aluminophosphates, surface properties, acidic-basic properties, Aldol, Claisen-Shmidth condensation, jasminaldehyde, chalcone

Procedia PDF Downloads 287
4545 Online Monitoring of Airborne Bioaerosols Released from a Composting, Green Waste Site

Authors: John Sodeau, David O'Connor, Shane Daly, Stig Hellebust

Abstract:

This study is the first to employ the online WIBS (Waveband Integrated Biosensor Sensor) technique for the monitoring of bioaerosol emissions and non-fluorescing “dust” released from a composting/green waste site. The purpose of the research was to provide a “proof of principle” for using WIBS to monitor such a location continually over days and nights in order to construct comparative “bioaerosol site profiles”. Current impaction/culturing methods take many days to achieve results available by the WIBS technique in seconds.The real-time data obtained was then used to assess variations of the bioaerosol counts as a function of size, “shape”, site location, working activity levels, time of day, relative humidity, wind speeds and wind directions. Three short campaigns were undertaken, one classified as a “light” workload period, another as a “heavy” workload period and finally a weekend when the site was closed. One main bioaerosol size regime was found to predominate: 0.5 micron to 3 micron with morphologies ranging from elongated to elipsoidal/spherical. The real-time number-concentration data were consistent with an Andersen sampling protocol that was employed at the site. The number-concentrations of fluorescent particles as a proportion of total particles counted amounted, on average, to ~1% for the “light” workday period, ~7% for the “heavy” workday period and ~18% for the weekend. The bioaerosol release profiles at the weekend were considerably different from those monitored during the working weekdays.

Keywords: bioaerosols, composting, fluorescence, particle counting in real-time

Procedia PDF Downloads 339
4544 Effective Factors on Farmers' Attitude toward Multifunctional Agriculture

Authors: Mohammad Sadegh Allahyari, Sorush Marzban

Abstract:

The main aim of this study was to investigate the factors affecting farmers' attitude of the Shanderman District in Masal (Guilan Province in the north of Iran), towards the concepts of multifunctional agriculture. The statistical population consisted of all 4908 in Shanderman.The sample of the present study consisted of 209 subjects who were selected from the total population using the Bartlett et al. Table. Questionnaire as the main tool of data collection was divided in two parts. The first part of questionnaire consisted of farmers' profiles regarding individual, technical-agronomic, economic and social characteristics. The second part included items to identify the farmers’ attitudes regarding different aspects of multifunctional agriculture. The validity of the questionnaire was assessed by professors and experts. Cronbach's alpha was used to determine the reliability (α= 0.844), which is considered an acceptable reliability value. Overall, the average scores of attitudes towards multifunctional agriculture show a positive tendency towards multifunctional agriculture, considering farmers' attitudes of the Shanderman district (SD = 0.53, M = 3.81). Results also highlight a significant difference between farmers' income source levels (F = 0.049) and agricultural literature review (F = 0.022) toward farmers' attitudes considering multifunctional agriculture (p < 0.05). Pearson correlations also indicated that there is a positive relationship between positive attitudes and family size (r = 0.154), farmers' experience (r = 0.246), size of land under cultivation (r = 0.186), income (r = 0.227), and social contribution activities (r = 0.224). The results of multiple regression analyses showed that the variation in the dependent variable depended on the farmers' experience in agricultural activities and their social contribution activities. This means that the variables included in the regression analysis are estimated to explain 12 percent of the variation in the dependent variable.

Keywords: multifunctional agriculture, attitude, effective factor, sustainable agriculture

Procedia PDF Downloads 220
4543 Evaluation of Goji By-Product as a Value-Added Ingredient for the Functional Food Industry

Authors: Sanaa Ragaee, Paragyani Bora, Wee Teng Tan, Xin Hu

Abstract:

Goji berry (Lycium barbarum) is a member of the family Solanaceae which is grown widely in China, Tibet, and other parts of Asia. Its fruits are 1–2 cm-long, bright orange-red ellipsoid berries and it has a long tradition as a food and medicinal plant. Goji berries are believed to boost immune system properties. The berries are considered an excellent source of macronutrients, micronutrients, vitamins, minerals and several bioactive components. Studies have shown effects of goji fruit on aging, neuroprotection, general well-being, fatigue/endurance, metabolism/energy expenditure, glucose control in diabetics and glaucoma, antioxidant properties, immunomodulation and anti-tumor activity. Goji berries are being used to prepare Goji beverage, and the remaining solid material is considered as by-product. The by-product is currently unused and disposed as waste despite its potential as a value-added food ingredient. Therefore, this study is intended to evaluate nutritional properties of Goji by-product and its potential applications in the baking industry. The Goji by-product was freeze dried and ground to pass through 1 mm screen prior to evaluation and food use. The Goji by-product was found to be a rich source of fiber (54%) and free phenolic components (1,307 µg/g), protein (13.6%), ash (3.3%) and fat (10%). Incorporation of the Goji by-product in muffins and cookies at various levels (10-40%) significantly improved the nutritional quality of the baked products. The baked products were generally accepted and highly rated by panelists at 20% replacement level. The results indicate the potential of Goji by-product as a value-added ingredient in particular as a source of dietary fiber and protein.

Keywords: Goji, by-product, phenolics, fibers, baked products

Procedia PDF Downloads 290
4542 Preparation of Nano-Scaled linbo3 by Polyol Method

Authors: Gabriella Dravecz, László Péter, Zsolt Kis

Abstract:

Abstract— The growth of optical LiNbO3 single crystal and its physical and chemical properties are well known on the macroscopic scale. Nowadays the rare-earth doped single crystals became important for coherent quantum optical experiments: electromagnetically induced transparency, slow down of light pulses, coherent quantum memory. The expansion of applications is increasingly requiring the production of nano scaled LiNbO3 particles. For example, rare-earth doped nanoscaled particles of lithium niobate can be act like single photon source which can be the bases of a coding system of the quantum computer providing complete inaccessibility to strangers. The polyol method is a chemical synthesis where oxide formation occurs instead of hydroxide because of the high temperature. Moreover the polyol medium limits the growth and agglomeration of the grains producing particles with the diameter of 30-200 nm. In this work nano scaled LiNbO3 was prepared by the polyol method. The starting materials (niobium oxalate and LiOH) were diluted in H2O2. Then it was suspended in ethylene glycol and heated up to about the boiling point of the mixture with intensive stirring. After the thermal equilibrium was reached, the mixture was kept in this temperature for 4 hours. The suspension was cooled overnight. The mixture was centrifuged and the particles were filtered. Dynamic Light Scattering (DLS) measurement was carried out and the size of the particles were found to be 80-100 nms. This was confirmed by Scanning Electron Microscope (SEM) investigations. The element analysis of SEM showed large amount of Nb in the sample. The production of LiNbO3 nano particles were succesful by the polyol method. The agglomeration of the particles were avoided and the size of 80-100nm could be reached.

Keywords: lithium-niobate, nanoparticles, polyol, SEM

Procedia PDF Downloads 116
4541 Biocontrol of Fusarium Crown and Root Rot and Enhancement of Tomato Solanum lycopersicum L. Growth Using Solanum linnaeanum L. Extracts

Authors: Ahlem Nefzi, Rania Aydi Ben Abdallah, Hayfa Jabnoun-Khiareddine, Nawaim Ammar, Sined Medimagh-Saidana, Mejda Daami-Remadi

Abstract:

In the present study, leaf, stem, and fruit aqueous extracts of native wild Solanum linnaeanum L. were screened for their ability to suppress Fusarium Crown and Root Rot disease and to enhance tomato (Solanum lycopersicum L.) growth under greenhouse conditions. Leaf extract used at 30% w/v was the most effective in reducing leaf and root damage index by 92.3% and the extent of vascular discoloration by 97.56% compared to Fusarium oxyxporum f. sp radicis lycopersici -inoculated and untreated control. A significant promotion of growth parameters (root length, shoot height, root and shoot biomass and stem diameter) was recorded on tomato cv. Rio Grande seedlings by 40.3-94.1% as compared to FORL inoculated control and by 9.6-88.8% over pathogen-free control. All S. linnaeanum aqueous extracts tested significantly stimulated the germination by 10.2 to 80.1% relative to the untreated control. FORL mycelial growth, assessed using the poisoned food technique, varied depending on plant organs, extracts, and concentrations used. Butanolic extracts were the most active, leading to 60.81% decrease in FORL mycelial growth. HPLC analysis of butanolic extract revealed the presence of thirteen phenolic compounds. Thus, S. linnaeanum can be explored as a potential natural source of antifungal and biofertilizing compounds.

Keywords: antifungal activity, HPLC-MS analysis, Fusarium oxysporum f. sp. radicis-lycopersici, tomato growth

Procedia PDF Downloads 145
4540 Predictive Analytics for Theory Building

Authors: Ho-Won Jung, Donghun Lee, Hyung-Jin Kim

Abstract:

Predictive analytics (data analysis) uses a subset of measurements (the features, predictor, or independent variable) to predict another measurement (the outcome, target, or dependent variable) on a single person or unit. It applies empirical methods in statistics, operations research, and machine learning to predict the future, or otherwise unknown events or outcome on a single or person or unit, based on patterns in data. Most analyses of metabolic syndrome are not predictive analytics but statistical explanatory studies that build a proposed model (theory building) and then validate metabolic syndrome predictors hypothesized (theory testing). A proposed theoretical model forms with causal hypotheses that specify how and why certain empirical phenomena occur. Predictive analytics and explanatory modeling have their own territories in analysis. However, predictive analytics can perform vital roles in explanatory studies, i.e., scientific activities such as theory building, theory testing, and relevance assessment. In the context, this study is to demonstrate how to use our predictive analytics to support theory building (i.e., hypothesis generation). For the purpose, this study utilized a big data predictive analytics platform TM based on a co-occurrence graph. The co-occurrence graph is depicted with nodes (e.g., items in a basket) and arcs (direct connections between two nodes), where items in a basket are fully connected. A cluster is a collection of fully connected items, where the specific group of items has co-occurred in several rows in a data set. Clusters can be ranked using importance metrics, such as node size (number of items), frequency, surprise (observed frequency vs. expected), among others. The size of a graph can be represented by the numbers of nodes and arcs. Since the size of a co-occurrence graph does not depend directly on the number of observations (transactions), huge amounts of transactions can be represented and processed efficiently. For a demonstration, a total of 13,254 metabolic syndrome training data is plugged into the analytics platform to generate rules (potential hypotheses). Each observation includes 31 predictors, for example, associated with sociodemographic, habits, and activities. Some are intentionally included to get predictive analytics insights on variable selection such as cancer examination, house type, and vaccination. The platform automatically generates plausible hypotheses (rules) without statistical modeling. Then the rules are validated with an external testing dataset including 4,090 observations. Results as a kind of inductive reasoning show potential hypotheses extracted as a set of association rules. Most statistical models generate just one estimated equation. On the other hand, a set of rules (many estimated equations from a statistical perspective) in this study may imply heterogeneity in a population (i.e., different subpopulations with unique features are aggregated). Next step of theory development, i.e., theory testing, statistically tests whether a proposed theoretical model is a plausible explanation of a phenomenon interested in. If hypotheses generated are tested statistically with several thousand observations, most of the variables will become significant as the p-values approach zero. Thus, theory validation needs statistical methods utilizing a part of observations such as bootstrap resampling with an appropriate sample size.

Keywords: explanatory modeling, metabolic syndrome, predictive analytics, theory building

Procedia PDF Downloads 257
4539 Understanding Talent Management In French Small And Medium-Sized Enterprises: Towards Multi-Level Modeling

Authors: Abid Kousay

Abstract:

Appeared and developed essentially in large companies and multinationals, Talent Management (TM) in Small and Medium-Sized Enterprises (SMEs) has remained an under-explored subject till today. Although the literature on TM in the Anglo-Saxon context is developing, it remains monopolized in non-European contexts, especially in France. Therefore, this article aims to address these shortcomings through contributing to TM issues by adopting a multilevel approach holding the goal of reaching a global holistic vision of interactions between various levels while applying TM. A qualitative research study carried out within 12 SMEs in France, built on the methodological perspective of grounded theory, will be used in order to go beyond description, to generate or discover a theory or even a unified theoretical explanation. Our theoretical contributions are the results of the grounded theory, the fruit of context considerations and the dynamic of the multilevel approach. We aim firstly to determine the perception of talent and TM in SMEs. Secondly, we formalize TM in SME through the empowerment of all 3 levels in the organization (individual, collective, and organizational). And we generate a multilevel dynamic system model, highlighting the institutionalization dimension in SMEs and the managerial conviction characterized by the domination of the leader’s role. Thirdly, this first study sheds light on the importance of rigorous implementation of TM in SMEs in France by directing CEO and HR and TM managers to focus on elements that upstream TM implementation and influence the system internally. Indeed, our systematic multilevel approach policy reminds them of the importance of strategic alignment while translating TM policy into strategies and practices in SMEs.

Keywords: French context, multilevel approach, talent management, , TM system

Procedia PDF Downloads 201
4538 Self-Stigma Regarding Mental Illness: An Empirical Study

Authors: Linta Koka

Abstract:

Aim: The way people with severe mental disorders deal with self-stigma and how it affects their self-esteem is a problem that has gained much attention in recent years. The primary aim of this study was to empirically explore the link between self-stigma and self-esteem of individuals with the presence of a mental illness, offering a novel perspective by exploring the same variables amongst a sample without a mental illness. Methods: This study utilized a cross-sectional study. Participants with (N=85) and without (N=75) a mental health issue were included from Darlingdon's Mind organization. Participants completed two scales, one of Self-Stigma of Mental Illness Scale and one of Self-Esteem, following some demographics questions. Results: According to the primary hypothesis, self-stigma significantly correlates with self-esteem in the clinical population. Furthermore, gender and ethnicity, above all the demographics, positively correlates to the relationship of self-stigma with self-esteem in people who endure a mental health issue. Limitations: A significant limitation is that of the size of the sample of participants conducted in this study. The clinical population was limited to 85 participants, and the control group consisted of 76 participants. Since the sample was not representative. The small size used did not allow any comparisons between the group with mental illness and the control group. There was a restricted time to approach the participants since the online survey was released by the end of May. Conclusions: Individuals suffering from mental illnesses may internalize stigmatizing stereotypes on an explicit level. Efforts should be made to lessen the harmful impact stigma may have on mentally ill people, such as worsening symptoms or delays in receiving care. Further study is needed within this small research topic to improve awareness and regulate mental health among the general population. Undoubtedly, people with mental disorders are stigmatized; therefore, more research is required to explore all factors contributing to mentally ill patients' devaluation.

Keywords: self-stigma, mental illness, self-esteem, clinical population, non-clinical population

Procedia PDF Downloads 49
4537 Improved Performance of Mn Substituted Ceria Nanospheres for Water Gas Shift Reaction: Influence of Preparation Conditions

Authors: Bhairi Lakshminarayana, Surajit Sarker, Ch. Subrahmanyam

Abstract:

The present study reports the development of noble metal free nano catalysts for low-temperature CO oxidation and water gas shift reaction. Mn-substituted CeO2 solid solution catalysts were synthesized by co-precipitation, combustion and hydrothermal methods. The formation of solid solution was confirmed by XRD with Rietveld refinement and the percentage of carbon and nitrogen doping was ensured by CHNS analyzer. Raman spectroscopic confirmed the oxygen vacancies. The surface area, pore volume and pore size distribution confirmed by N2 physisorption analysis, whereas, UV-visible diffuse reflectance spectroscopy and XPS data confirmed the oxidation state of the Mn ion. The particle size and morphology (spherical shape) of the material was confirmed using FESEM and HRTEM analysis. Ce0.8Mn0.2O2-δ was calcined at 400 °C, 600 °C and 800 °C. Raman spectroscopy confirmed that the catalyst calcined at 400 °C has the best redox properties. The activity of the designed catalysts for CO oxidation (0.2 vol%), carried out with GHSV of 21,000 h-1 and it has been observed that co-precipitation favored the best active catalyst towards CO oxidation and water gas shift reaction, due to the high surface area, improved reducibility, oxygen mobility and highest quantity of surface oxygen species. The activation energy of low temperature CO oxidation on Ce0.8Mn0.2O2- δ (combustion) was 5.5 kcal.K-1.mole-1. The designed catalysts were tested for water gas shift reaction. The present study demonstrates that Mn ion substituted ceria at 400 °C calcination temperature prepared by co-precipitation method promise to revive a green sustainable energy production approach.

Keywords: Ce0.8Mn0.2O2-ð, CO oxidation, physicochemical characterization, water gas shift reaction (WGS)

Procedia PDF Downloads 219
4536 In vitro Study on Characterization and Viability of Vero Cell Lines after Supplementation with Porcine Follicular Fluid Proteins in Culture Medium

Authors: Mayuva Youngsabanant, Suphaphorn Rabiab, Hatairuk Tungkasen, Nongnuch Gumlungpat, Mayuree Pumipaiboon

Abstract:

The porcine follicular fluid proteins (pFF) of healthy small size ovarian follicles (1-3 mm in diameters) of Large White pig ovaries were collected by sterile technique. They were used for testing the effect on cell viability and characterization of Vero cell lines using MTT assay. Two hundred microliter of round shape Vero cell lines were culture in 96 well plates with DMEM for 24 h. After that, they were attachment to substrate and some changed into fibroblast shape and spread over the surface after culture for 48 h. Then, Vero cell lines were treated with pFF at concentration of 2, 4, 20, 40, 200, 400, 500, and 600 µg proteins/mL for 24 h. Yields of the best results were analyzed by using one-way ANOVA. MTT assay reviewed an increasing in percentage of viability of Vero cell lines indicated that at concentration of 400-600 µg proteins/mL showed higher percentage of viability (115.64 ± 6.95, 106.91 ± 5.27 and 116.73 ± 20.15) than control group. They were significantly different from the control group (p < 0.05) but lower than the positive control group (DMEM with 10% heat treated fetal bovine serum). Cell lines showed normal character in fibroblast elongate shape after treated with pFF except in high concentration of pFF. This result implies that pFF of small size ovarian follicle at concentration of 400-600 µg proteins/mL could be optimized concentration for using as a supplement in Vero cell line culture medium to promote cell viability instead of growth hormone from fetal bovine serum. This merit could be applied in other cell biotechnology researches. Acknowledgements: This work was funded by a grant from Silpakorn University and Faculty of Science, Silpakorn University, Thailand.

Keywords: cell viability, porcine follicular fluid, MTT assay, Vero cell line

Procedia PDF Downloads 117
4535 Assessment of the Effect of Farmer-Herder Conflict on the Livelihood of Rural Households in Bogoro Local Government Area of Bauchi State, Nigeria

Authors: Luka Jumma Gizaki

Abstract:

The study assessed the effect of farmer-herder conflict on the livelihood of rural households in Bogoro L.G.A., Bauchi State, Nigeria. Multistage sampling procedures were used to randomly select 66 crop farmers in the study area. Data were collected by means of a structured questionnaire. The result was analyzed using descriptive and inferential statistics. Results showed that the majority of the respondents were males with a mean age of 39 years and a farming experience of 16 years. About 95% of the respondents had formal education, with a mean household size of 8 persons per household. Farmer-herder conflicts were found to be caused by grazing on growing crops, wrong approach by farmers in raising complaints and harassment of herdsmen, absence of grazing route and poisoning of uncultivated lands. Constraints to resolving conflict were found to include personal interest, lack of government will, ethnicity and religious difference and open grazing ranking first, second and third, among others. Six factors connected to farmer-herder conflict were found to significantly affect the livelihood of rural households. These were the value of crops destroyed, the number of livestock lost, and the cost of treatment of wounds sustained from the conflict. The value of crops and the size of farmland abandoned in fear were significant, and the cost of seeking redress was significant at P≤0.01. It was concluded that farmer-herder conflict impacts negatively not only crops and animals but also affects the lives of farmers and herders as well as their economy. It is recommended that proper methods be adopted to avoid its occurrence, and when it occurs, the erring party should be appropriately punished.

Keywords: farmer, herder, conflict, effect, coping

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4534 Influence of Cryo-Grinding on Antioxidant Activity and Amount of Free Phenolic Acids, Rutin and Tyrosol in Whole Grain Buckwheat and Pumpkin Seed Cake

Authors: B. Voucko, M. Benkovic, N. Cukelj, S. Drakula, D. Novotni, S. Balbino, D. Curic

Abstract:

Oxidative stress is considered as one of the causes leading to metabolic disorders in humans. Therefore, the ability of antioxidants to inhibit free radical production is their primary role in the human organism. Antioxidants originating from cereals, especially flavonoids and polyphenols, are mostly bound and indigestible. Micronization damages the cell wall which consecutively results in bioactive material to be more accessible in vivo. In order to ensure complete fragmentation, micronization is often combined with high temperatures (e.g., for bran 200°C) which can lead to degradation of bioactive compounds. The innovative non-thermal technology of cryo-milling is an ultra-fine micronization method that uses liquid nitrogen (LN2) at a temperature of 195°C to freeze and cool the sample during milling. Freezing at such low temperatures causes the material to become brittle which ensures the generation of fine particles while preserving the bioactive content of the material. The aim of this research was to determine if production of ultra-fine material with cryo-milling will result in the augmentation of available bioactive compounds of buckwheat and pumpkin seed cake. For that reason, buckwheat and pumpkin seed cake were ground in a ball mill (CryoMill, Retch, Germany) with and without the use of LN2 for 8 minutes, in a 50 mL stainless steel jar containing one grinding ball (Ø 25 mm) at an oscillation frequency of 30 Hz. The cryo-milled samples were cooled with LN2 for 2 minutes prior to milling, followed by the first cycle of milling (4 minutes), intermediary cooling (2 minutes), and finally the second cycle of milling (further 4 minutes). A continuous process of milling was applied to the samples ground without freezing with LN2. Particle size distribution was determined using the Scirocco 2000 dry dispersion unit (Malvern Instruments, UK). Antioxidant activity was determined by 2,2-Diphenyl-1-picrylhydrazyl (DPPH) test and ferric reducing antioxidant power (FRAP) assay, while the total phenol content was determined using the Folin Ciocalteu method, using the ultraviolet-visible spectrophotometer (Specord 50 Plus, Germany). The content of the free phenolic acids, rutin in buckwheat, tyrosol in pumpkin seed cake, was determined with an HPLC-PDA method (Agilent 1200 series, Germany). Cryo-milling resulted in 11 times smaller size of buckwheat particles, and 3 times smaller size of pumpkin seed particles than milling without the use of LN2, but also, a lower uniformity of the particle size distribution. Lack of freezing during milling of pumpkin seed cake caused a formation of agglomerates due to its high-fat content (21 %). Cryo-milling caused augmentation of buckwheat flour antioxidant activity measured by DPPH test (23,9%) and an increase in available rutin content (14,5%). Also, it resulted in an augmentation of the total phenol content (36,9%) and available tyrosol content (12,5%) of pumpkin seed cake. Antioxidant activity measured with the FRAP test, as well as the content of phenolic acids remained unchanged independent of the milling process. The results of this study showed the potential of cryo-milling for complete raw material utilization in the food industry, as well as a tool for extraction of aimed bioactive components.

Keywords: bioactive, ball-mill, buckwheat, cryo-milling, pumpkin seed cake

Procedia PDF Downloads 123
4533 A Disappearing Radiolucency of the Mandible Caused by Inadvertent Trauma Following IMF Screw Placement

Authors: Anna Ghosh, Dominic Shields, Ceri McIntosh, Stephen Crank

Abstract:

A 29-year-old male was a referral to the maxillofacial unit following a referral from his general dental practitioner via a routine pathway regarding a large periapical lesion on the LR4 with root resorption. The patient was asymptomatic, the LR4 vital and unrestored, and this was an incidental finding at a routine check-up. The patient's past medical history was unremarkable. Examination revealed no extra or intra-oral pathology and non-mobile teeth. No focal neurology was detected. An orthopantogram demonstrated a well-defined unilocular corticated radiolucency associated with the LR4. The root appeared shortened with the radiolucency between the root and a radio-opacity, possibly representing the displacement of the apical tip of the tooth. It was recommended that the referring general practitioner should proceed with orthograde root canal therapy, after which time exploration, enucleation, and retrograde root filling of the LR4 would be carried out by a maxillofacial unit. The patient was reviewed six months later where, due to the COVID-19 pandemic, the patient had been unable to access general dental services for the root canal treatment. He was still entirely asymptomatic. A one-year review was planned in the hope this would allow time for the orthograde root canal therapy to be completed. At this review, the orthograde root canal therapy had still not been completed. Interestingly, a repeat orthopantogram revealed a significant reduction in size with good bony infill and a significant reduction in the size of the lesion. Due to the ongoing delays with primary care dental therapy, the patient was subsequently internally referred to the restorative dentistry department for care. The patient was seen again by oral and maxillo-facial surgery in mid-2022 where he still reports this tooth as asymptomatic with no focal neurology. The patient's history was fully reviewed, and noted that 15 years previously, the patient underwent open reduction and internal fixation of a left angle of mandible fracture. Temporary IMF involving IMF screws and fixation wires were employed to maintain occlusion during plating and subsequently removed post-operatively. It is proposed that the radiolucency was, as a result of the IMF screw placement, penetrating the LR4 root resulting in resorption of the tooth root and development of a radiolucency. This case highlights the importance of careful screw size and physical site location, and placement of IMF screws, as there can be permeant damage to a patient’s dentition.

Keywords: facial trauma, inter-maxillary fixation, mandibular radiolucency, oral and maxillo-facial surgery

Procedia PDF Downloads 114
4532 Molecular Dynamic Simulation of Cold Spray Process

Authors: Aneesh Joshi, Sagil James

Abstract:

Cold Spray (CS) process is deposition of solid particles over a substrate above a certain critical impact velocity. Unlike thermal spray processes, CS process does not melt the particles thus retaining their original physical and chemical properties. These characteristics make CS process ideal for various engineering applications involving metals, polymers, ceramics and composites. The bonding mechanism involved in CS process is extremely complex considering the dynamic nature of the process. Though CS process offers great promise for several engineering applications, the realization of its full potential is limited by the lack of understanding of the complex mechanisms involved in this process and the effect of critical process parameters on the deposition efficiency. The goal of this research is to understand the complex nanoscale mechanisms involved in CS process. The study uses Molecular Dynamics (MD) simulation technique to understand the material deposition phenomenon during the CS process. Impact of a single crystalline copper nanoparticle on copper substrate is modelled under varying process conditions. The quantitative results of the impacts at different velocities, impact angle and size of the particles are evaluated using flattening ratio, von Mises stress distribution and local shear strain. The study finds that the flattening ratio and hence the quality of deposition was highest for an impact velocity of 700 m/s, particle size of 20 Å and an impact angle of 90°. The stress and strain analysis revealed regions of shear instabilities in the periphery of impact and also revealed plastic deformation of the particles after the impact. The results of this study can be used to augment our existing knowledge in the field of CS processes.

Keywords: cold spray process, molecular dynamics simulation, nanoparticles, particle impact

Procedia PDF Downloads 353
4531 Towards a Multilevel System of Talent Management in Small And Medium-Sized Enterprises: French Context Exploration

Authors: Abid Kousay

Abstract:

Appeared and developed essentially in large companies and multinationals, Talent Management (TM) in Small and Medium-Sized Enterprises (SMEs) has remained an under-explored subject till today. Although the literature on TM in the Anglo-Saxon context is developing, it remains monopolized in non-European contexts, especially in France. Therefore, this article aims to address these shortcomings through contributing to TM issues, by adopting a multilevel approach holding the goal of reaching a global holistic vision of interactions between various levels, while applying TM. A qualitative research study carried out within 12 SMEs in France, built on the methodological perspective of grounded theory, will be used in order to go beyond description, to generate or discover a theory or even a unified theoretical explanation. Our theoretical contributions are the results of the grounded theory, the fruit of context considerations and the dynamic of the multilevel approach. We aim firstly to determine the perception of talent and TM in SMEs. Secondly, we formalize TM in SME through the empowerment of all 3 levels in the organization (individual, collective, and organizational). And we generate a multilevel dynamic system model, highlighting the institutionalization dimension in SMEs and the managerial conviction characterized by the domination of the leader's role. Thirdly, this first study shed the light on the importance of rigorous implementation of TM in SMEs in France by directing CEO and HR and TM managers to focus on elements that upstream TM implementation and influence the system internally. Indeed, our systematic multilevel approach policy reminds them of the importance of the strategic alignment while translating TM policy into strategies and practices in SMEs.

Keywords: French context, institutionalization, talent, multilevel approach, talent management system

Procedia PDF Downloads 185
4530 Influence of Parent’s Food Habits on Nutrition Behaviours of Children under 7 Years in Tehran, Iran

Authors: Katayoun Bagheri, Farzad Berahmandpour

Abstract:

Several studies about food habits in diverse population show, early living years play significant role in building of current food habits. Suitable nutrition in children is also influenced by parent’s food habits. The aim of study is to survey the role of parent’s food habits to form of nutrition behaviours in children under 7 years in Tehran - Iran. The study is a Descriptive study. The participants were 19 children under 7 years with their mothers from a kindergarten in the central Tehran. The sampling method was random sampling. The data was collected by food habits questionnaires and implementation of consultation meetings with the mothers. The data analysis was qualitative analysis. The findings show that 79% children and their parents have eaten enough and variety breakfast, but food choices of children were depended on food choices of parents. In the other meals, the majority of children enjoyed to eat dinner (58%), because the more families could eat dinner together. According to mother opinions, the children enjoy eating macaroni, chicken, fried potatoes, chips and fruit juices. The researchers argue that mother’s role is unavoidable in the food preferences among children. Fortunately, the results believe that children tend to drink simple milk (79%). Moreover, their parents lead them to chocolate milk consumption (42%) instead of other flavored milk. Finally, despite popular belief claim that mothers influence on nutrition behavior of children, but the study argues that the fathers have more effects on children’s nutrition behaviours. In conclusion, it seems that the general trainings about promoting healthy nutrition behavior for parents by mass media can improve nutrition habits and behaviours of pre school children.

Keywords: food habits, parents, nutrition behaviours, children, promoting nutrition

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4529 Use of Waste Glass as Coarse Aggregate in Concrete: A Possibility towards Sustainable Building Construction

Authors: T. S. Serniabat, M. N. N. Khan, M. F. M. Zain

Abstract:

As climate change and environmental pressures are now well established as major international issues, to which governments, businesses and consumers have to respond through more environmentally friendly and aware practices, products and policies; the need to develop alternative sustainable construction materials, reduce greenhouse gas emissions, save energy, look to renewable energy sources and recycled materials, and reduce waste are just some of the pressures impacting significantly on the construction industry. The utilization of waste materials (slag, fly ash, glass beads, plastic and so on) in concrete manufacturing is significant due to engineering, financial, environmental and ecological importance. Thus, utilization of waste materials in concrete production is very much helpful to reach the goal of the sustainable construction. Therefore, this study intends to use glass beads in concrete production. The paper reports on the performance of 9 different concrete mixes containing different ratios of glass crushed to 5 mm - 20 mm maximum size and glass marble of 20 mm size as coarse aggregate .Ordinary Portland cement type 1 and fine sand less than 0.5 mm were used to produce standard concrete cylinders. Compressive strength tests were carried out on concrete specimens at various ages. Test results indicated that the mix having the balanced ratio of glass beads and round marbles possess maximum compressive strength which is 3888.68 psi, as glass beads perform better in bond formation but have lower strength, on the other hand marbles are strong in themselves but not good in bonding. These mixes were prepared following a specific W/C and aggregate ratio; more strength can be expected to achieve from different W/C, aggregate ratios, adding admixtures like strength increasing agents, ASR inhibitor agents etc.

Keywords: waste glass, recycling, environmentally friendly, glass aggregate, strength development

Procedia PDF Downloads 366
4528 Detection of the Effectiveness of Training Courses and Their Limitations Using CIPP Model (Case Study: Isfahan Oil Refinery)

Authors: Neda Zamani

Abstract:

The present study aimed to investigate the effectiveness of training courses and their limitations using the CIPP model. The investigations were done on Isfahan Refinery as a case study. From a purpose point of view, the present paper is included among applied research and from a data gathering point of view, it is included among descriptive research of the field type survey. The population of the study included participants in training courses, their supervisors and experts of the training department. Probability-proportional-to-size (PPS) was used as the sampling method. The sample size for participants in training courses included 195 individuals, 30 supervisors and 11 individuals from the training experts’ group. To collect data, a questionnaire designed by the researcher and a semi-structured interview was used. The content validity of the data was confirmed by training management experts and the reliability was calculated through 0.92 Cronbach’s alpha. To analyze the data in descriptive statistics aspect (tables, frequency, frequency percentage and mean) were applied, and inferential statistics (Mann Whitney and Wilcoxon tests, Kruskal-Wallis test to determine the significance of the opinion of the groups) have been applied. Results of the study indicated that all groups, i.e., participants, supervisors and training experts, absolutely believe in the importance of training courses; however, participants in training courses regard content, teacher, atmosphere and facilities, training process, managing process and product as to be in a relatively appropriate level. The supervisors also regard output to be at a relatively appropriate level, but training experts regard content, teacher and managing processes as to be in an appropriate and higher than average level.

Keywords: training courses, limitations of training effectiveness, CIPP model, Isfahan oil refinery company

Procedia PDF Downloads 52
4527 Encapsulation of Flexible OLED with an Auxiliary Sealing Line

Authors: Hanjun Yun, Gun Bae, Nabin Paul, Cheolhee Moon

Abstract:

Flexible OLED is an important technology for the next generation display over various kinds of applications. However, the organic materials of OLEDs degrade rapidly under the invasion of oxygen and water moisture. The degradation causes the formation of non-emitting areas which gradually suppress the device brightness, ultimately the lifetime of the device decreasing rapidly. Until now, the most suitable sealing process of the flexible OLED devices is a thin film encapsulation (TFE). However, TFE consists of a multilayer thin-film structure with organic-inorganic materials, so the cost is expensive and the process time is long. Another problem is that the blocking characteristics from the moisture and oxygen are not perfect. Therefore, the encapsulation of the flexible OLED device is a still key technical issue for the successful market entry. In this study, we are to introduce an auxiliary sealing line between the two flexible substrates. The electrode lines were formed on the substrates which have a SiNx barrier coating layer. To induce the solid phase diffusion process between the SiNx layer and the electrode lines, the electrode materials were determined as Al-Si composition. Thermal energy was supplied for both the SiNx layer and Al-Si electrode lines within the furnace to induce the interfacial bonding through the solid phase diffusion of Si. We printed a test pattern for the edge of the flexible PET substrate of 3cm*3cm size. Experimental conditions such as heating temperature, heating time were optimized to get enough adhesion strength which was estimated through the competitive bending test. Finally, OLED devices with flexible PET substrate of 3cm*3cm size were manufactured to investigate the blocking characteristics as an encapsulation layer.

Keywords: barrier, encapsulation, OLED, solid phase diffusion

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4526 Characterizing Nanoparticles Generated from the Different Working Type and the Stack Flue during 3D Printing Process

Authors: Kai-Jui Kou, Tzu-Ling Shen, Ying-Fang Wang

Abstract:

The objectives of the present study are to characterize nanoparticles generated from the different working type in 3D printing room and the stack flue during 3D printing process. The studied laboratory (10.5 m× 7.2 m × 3.2 m) with a ventilation rate of 500 m³/H is installed a 3D metal printing machine. Direct-reading instrument of a scanning mobility particle sizer (SMPS, Model 3082, TSI Inc., St. Paul, MN, USA) was used to conduct static sampling for nanoparticle number concentration and particle size distribution measurements. The SMPS obtained particle number concentration at every 3 minutes, the diameter of the SMPS ranged from 11~372 nm when the aerosol and sheath flow rates were set at 0.6 and 6 L/min, respectively. The concentrations of background, printing process, clearing operation, and screening operation were performed in the laboratory. On the other hand, we also conducted nanoparticle measurement on the 3D printing machine's stack flue to understand its emission characteristics. Results show that the nanoparticles emitted from the different operation process were the same distribution in the form of the uni-modal with number median diameter (NMD) as approximately 28.3 nm to 29.6 nm. The number concentrations of nanoparticles were 2.55×10³ count/cm³ in laboratory background, 2.19×10³ count/cm³ during printing process, 2.29×10³ count/cm³ during clearing process, 3.05×10³ count/cm³ during screening process, 2.69×10³ count/cm³ in laboratory background after printing process, and 6.75×10³ outside laboratory, respectively. We found that there are no emission nanoparticles during the printing process. However, the number concentration of stack flue nanoparticles in the ongoing print is 1.13×10⁶ count/cm³, and that of the non-printing is 1.63×10⁴ count/cm³, with a NMD of 458 nm and 29.4 nm, respectively. It can be confirmed that the measured particle size belongs to easily penetrate the filter in theory during the printing process, even though the 3D printer has a high-efficiency filtration device. Therefore, it is recommended that the stack flue of the 3D printer would be equipped with an appropriate dust collection device to prevent the operators from exposing these hazardous particles.

Keywords: nanoparticle, particle emission, 3D printing, number concentration

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4525 Nutritional Wellness at the Workplace

Authors: Siveshnee Devar

Abstract:

Background: The rate of absenteeism and prevalence of NCDs in South Africa is extremely high. This is consistent with other educational institutions and workplaces around the globe. In most cases the absence of health and the presence of one or more non communicable diseases coupled with the lack of physical exercise is a major factor in absenteeism. Absenteeism at the workplace comes at a huge cost to the employer and the country as a whole. Aim: Findings from this study was to develop a suitable nutritional wellness program for the workplace. Methodology: A needs analysis in the form of 24-hour recall, food frequency, health and socio demographic questionnaires was undertaken to determine the need for a wellness program for the institution. Anthropometric indices such as BMI, waist circumference and blood pressure were also undertaken to determine the state of health of the staff. Results: This study has found that obesity, central obesity, hypertension as well as deficiencies in nutrients and minerals were prevalent in this group. Fruit and vegetable consumption was also below the WHO recommendation. This study showed a link between diet, physical activity and diseases of lifestyle. There were positive correlations between age and systolic blood pressure, waist circumference and systolic blood pressure, waist circumference and diastolic blood pressure and waist-to-height ratio and BMI. Conclusion: The results indicated the need for immediate intervention in the form of a wellness program. Nutrition education is important for both the workplace and out. Education and knowledge are important factors for lifestyle changes. The proposed intervention is aimed at improving presenteeism and decreasing the incidence of non- communicable diseases. Presenteeism and good health are important factors for quality education at all educational institutions.

Keywords: absenteeism, non-communicable diseases, nutrition, wellness

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4524 Societal Stakes for Small Cruise Ships: A Recurrent Issue of Our Time

Authors: Maud Tixier

Abstract:

Societal issues are at stake for cruises anywhere, whatever the size of the ships and their destinations are. However, the Mediterranean sea is the main region where many operate and the challenges are both social and environmental. The presentation focuses on small ships, accounting for market niches, aimed at more specific cruise passengers and calling at less visited areas. How they cope with the benefit of all stakeholders is a persistent issue of our time.

Keywords: environment, management, social, societal, safety

Procedia PDF Downloads 315
4523 Ultrasound-Assisted Sol – Gel Synthesis of Nano-Boehmite for Biomedical Purposes

Authors: Olga Shapovalova, Vladimir Vinogradov

Abstract:

Among many different sol – gel matrices only alumina can be successfully parenteral injected in the human body. And this is not surprising, because boehmite (aluminium oxyhydroxide) is the metal oxide approved by FDA and EMA for intravenous and intramuscular administrations, and also has been using for a longtime as adjuvant for producing of many modern vaccines. In our earlier study, it has been shown, that denaturation temperature of enzymes entrapped in sol-gel boehmite matrix increases for 30 – 60 °С with preserving of initial activity. It makes such matrices more attractive for long-term storage of non-stable drugs. In current work we present ultrasound-assisted sol-gel synthesis of nano-boehmite. This method provides bio-friendly, very stable, highly homogeneous alumina sol with using only water and aluminium isopropoxide as a precursor. Many parameters of the synthesis were studied in details: time of ultrasound treatment, US frequency, surface area, pore and nanoparticle size, zeta potential and others. Here we investigated the dependence of stability of colloidal sols and textural properties of the final composites as a function of the time of ultrasonic treatment. Chosen ultrasonic treatment time was between 30 and 180 minutes. Surface area, average pore diameter and total pore volume of the final composites were measured by surface and pore size analyzer Nova 1200 Quntachrome. It was shown that the matrices with ultrasonic treatment time equal to 90 minutes have the biggest surface area 431 ± 24 m2/g. On the other had such matrices have a smaller stability in comparison with the samples with ultrasonic treatment time equal to 120 minutes that have the surface area 390 ± 21 m2/g. It was shown that the stable sols could be formed only after 120 minutes of ultrasonic treatment, otherwise the white precipitate of boehmite is formed. We conclude that the optimal ultrasonic treatment time is 120 minutes.

Keywords: boehmite matrix, stabilisation, ultrasound-assisted sol-gel synthesis

Procedia PDF Downloads 248
4522 A Study Problem and Needs Compare the Held of the Garment Industries in Nonthaburi and Bangkok Area

Authors: Thepnarintra Praphanphat

Abstract:

The purposes of this study were to investigate garment industry’s condition, problems, and need for assistance. The population of the study was 504 managers or managing directors of garment establishments finished apparel industrial manager and permission of the Department of Industrial Works 28, Ministry of Industry until January 1, 2012. In determining the sample size with the opening of the Taro Yamane finished at 95% confidence level is ± 5% deviation was 224 managers. Questionnaires were used to collect the data. Percentage, frequency, arithmetic mean, standard deviation, t-test, ANOVA, and LSD were used to analyze the data. It was found that most establishments were of a large size, operated in a form of limited company for more than 15 years most of which produced garments for working women. All investment was made by Thai people. The products were made to order and distributed domestically and internationally. The total sale of the year 2010, 2011, and 2012 was almost the same. With respect to the problems of operating the business, the study indicated, as a whole, by- aspects, and by-items, that they were at a high level. The comparison of the level of problems of operating garment business as classified by general condition showed that problems occurring in business of different sizes were, as a whole, not different. In taking aspects into consideration, it was found that the level of problem in relation to production was different; medium establishments had more problems in production than those of small and large sizes. According to the by-items analysis, five problems were found different; namely, problems concerning employees, machine maintenance, number of designers, and price competition. Such problems in the medium establishments were at a higher level than those in the small and large establishments. Regarding business age, the examination yielded no differences as a whole, by-aspects, and by-items. The statistical significance level of this study was set at .05.

Keywords: garment industry, garment, fashion, competitive enhancement project

Procedia PDF Downloads 175
4521 Influence of Socio-Economic Factors on Crime Perpetuation Among Inmates of Correctional Facilities in South-West Nigeria

Authors: Ebenezer Bayode Agboola

Abstract:

The study investigated the influence of socioeconomic factors on crime perpetuation among inmates of correctional facilities in South West Nigeria. A sample size of two hundred and forty-four inmates was drawn from Ado, Akure and Ilesha correctional facilities. The sample size consisted of both male and female inmates. Individual inmate was drawn through systematic sampling with the use of inmates’ register at the correctional facilities. The study employed a mixed design, which allowed the blend of both quantitative and qualitative methods. For the quantitative method, data was collected through the use of a questionnaire and for the qualitative method; data was collected with the aid of an in-depth interview (ID. Four research questions were raised for the study and analysed descriptively using simple frequency count and percentage. Five research hypotheses were formulated for the study and tested using Analysis of Variance (ANOVA) and Multiple Regressions. Based on the data analysis, findings revealed that there was a significant relationship between family history and perpetuation of crime among inmates. Though no significant relationship was found between employment and the perpetuation of crime, however, the rate of crime perpetuation by individuals was significantly found to be related to peer pressure. Also, the study further found that there was a significant relationship between the use of substances and perpetuation of crime. Lastly, it was found that there was a significant relationship between family history, employment, and peer pressure. The study recommended that Parents should pay adequate attention to their children, especially during the adolescent stage and that the Government should enact relevant laws that will checkmate the rising involvement of young people in cybercrime or internet fraud.

Keywords: crime, socio economic factor, inmates, correctional facilities, Southwest

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4520 Effects of Audit Quality and Corporate Governance on Earnings Management of Quoted Deposit Money Banks in Nigeria

Authors: Joel S. Akintayo, Ramat T. Salman

Abstract:

The stakeholders’ pressure on corporate managers to maintain firm’s profitability has created economic incentives for management to engage in earnings management practices. Therefore, this study examines the effects of audit quality and corporate governance on earnings management of quoted deposit money banks (DMBs) in Nigeria. This study specifically investigates the influence of audit tenure, audit fee, board independence, and board size on earnings management of DMBs. Explanatory research design was employed in carrying out the study while secondary data were sourced from the annual reports and accounts of all the 15 quoted DMBs in Nigerian Stock Exchange as at December 31, 2015 for a period of 10 years covering from 2006 to 2015. The data obtained for the study were analyzed using panel regression analysis approach. The findings reveal that board independence has a negative significant effect on earnings management at a 5% level of significance (p=0.002), while audit fee has a positive significant effect on earnings management at a 5% level of significance (p=0.013) and audit tenure has a negative significant effect on earnings management of DMBs at a 5% level of significance (p=0.003). Surprisingly, board size was statistically not significant at a 5% level of significance (p=0.086). The study concludes that high audit quality and sound corporate governance could improve the earnings quality of DMBs. Hence, the study recommends that the authorities saddled with the responsibility of banking supervision in Nigeria such the Securities and Exchange Commission (SEC) and CBN to advise the National Assembly in Nigeria to pass into law the three years professional requirement for audit tenure.

Keywords: audit quality, audit tenure, audit fee, board independence, corporate governance, earnings management

Procedia PDF Downloads 172
4519 Search for APN Permutations in Rings ℤ_2×ℤ_2^k

Authors: Daniel Panario, Daniel Santana de Freitas, Brett Stevens

Abstract:

Almost Perfect Nonlinear (APN) permutations with optimal resistance against differential cryptanalysis can be found in several domains. The permutation used in the standard for symmetric cryptography (the AES), for example, is based on a special kind of inversion in GF(28). Although very close to APN (2-uniform), this permutation still contains one number 4 in its differential spectrum, which means that, rigorously, it must be classified as 4-uniform. This fact motivates the search for fully APN permutations in other domains of definition. The extremely high complexity associated to this kind of problem precludes an exhaustive search for an APN permutation with 256 elements to be performed without the support of a suitable mathematical structure. On the other hand, in principle, there is nothing to indicate which mathematically structured domains can effectively help the search, and it is necessary to test several domains. In this work, the search for APN permutations in rings ℤ2×ℤ2k is investigated. After a full, exhaustive search with k=2 and k=3, all possible APN permutations in those rings were recorded, together with their differential profiles. Some very promising heuristics in these cases were collected so that, when used as a basis to prune backtracking for the same search in ℤ2×ℤ8 (search space with size 16! ≅244), just a few tenths of a second were enough to produce an APN permutation in a single CPU. Those heuristics were empirically extrapolated so that they could be applied to a backtracking search for APNs over ℤ2×ℤ16 (search space with size 32! ≅2117). The best permutations found in this search were further refined through Simulated Annealing, with a definition of neighbors suitable to this domain. The best result produced with this scheme was a 3-uniform permutation over ℤ2×ℤ16 with only 24 values equal to 3 in the differential spectrum (all the other 968 values were less than or equal 2, as it should be the case for an APN permutation). Although far from being fully APN, this result is technically better than a 4-uniform permutation and demanded only a few seconds in a single CPU. This is a strong indication that the use of mathematically structured domains, like the rings described in this work, together with heuristics based on smaller cases, can lead to dramatic cuts in the computational resources involved in the complexity of the search for APN permutations in extremely large domains.

Keywords: APN permutations, heuristic searches, symmetric cryptography, S-box design

Procedia PDF Downloads 144
4518 Effects of Roughness on Forward Facing Step in an Open Channel

Authors: S. M. Rifat, André L. Marchildon, Mark F. Tachie

Abstract:

Experiments were performed to investigate the effects of roughness on the reattachment and redevelopment regions over a 12 mm forward facing step (FFS) in an open channel flow. The experiments were performed over an upstream smooth wall and a smooth FFS, an upstream wall coated with sandpaper 36 grit and a smooth FFS and an upstream rough wall produced from sandpaper 36 grit and a FFS coated with sandpaper 36 grit. To investigate only the wall roughness effects, Reynolds number, Froude number, aspect ratio and blockage ratio were kept constant. Upstream profiles showed reduced streamwise mean velocities close to the rough wall compared to the smooth wall, but the turbulence level was increased by upstream wall roughness. The reattachment length for the smooth-smooth wall experiment was 1.78h; however, when it is replaced with rough-smooth wall the reattachment length decreased to 1.53h. It was observed that the upstream roughness increased the physical size of contours of maximum turbulence level; however, the downstream roughness decreased both the size and magnitude of contours in the vicinity of the leading edge of the step. Quadrant analysis was performed to investigate the dominant Reynolds shear stress contribution in the recirculation region. The Reynolds shear stress and turbulent kinetic energy profiles after the reattachment showed slower recovery compared to the streamwise mean velocity, however all the profiles fairly collapse on their corresponding upstream profiles at x/h = 60. It was concluded that to obtain a complete collapse several more streamwise distances would be required.

Keywords: forward facing step, open channel, separated and reattached turbulent flows, wall roughness

Procedia PDF Downloads 374
4517 Evaluation of the Predatory Mites' Manner against Root-Knot Nematode Using Water Agar Technique

Authors: Abdelrady K. Nasr, Ezzat M. A. Noweer, Mahmoud M. Ramadan

Abstract:

The root-knot nematode, Meloidogyne incognita Kofoid and White (Tylenchida: Heteroderidae), is one of the most important plant-parasitic nematodes attacking large numbers of vegetable and fruit plants in Egypt. Moreover, the soil predatory mites (Protogamasellopsisdenticus (Nasr), Gaeolaelaps longus (Hafez, El-Badry and Nasr) and Cosmolaelapskeni(Hafez, El-Badry and Nasr) are one of the excellent agents for biocontrol, this study was designed to evaluate the predation of the root-knot nematode (M. incognita) using water agar technique. The water agar medium was used as an experimental medium to rear both the mentioned mites and egg masses; these media allowed observe the development and predacious manner. The present study revealed that the predatory mites successfully developed and reproduced their egg masses. The mean life cycle of the tested mites P. denticus, G. longus, and C.keni were 10.33, 12.00, and 9.77 days, respectively. The mean total life span of the female of P. denticus, G. longus, and C. keni on egg-mases of M. incognita were obtained 63.44, 77.55 and 70.11 days, respectively, and the mean total fecundity of predatory mites, P. denticus, G.longus, and C. keni on egg-mases nematode were observed 62.66, 31.61 and 11.83 eggs, respectively. The mean total number of eggs laid by female P. denticus was significantly higher than other predatory mites, G. longus and C. keni. According to the obtained results, the tested predacious mites can be applied to combat the spreading of M. incognita in the agriculture field as a safe and effective biological control.

Keywords: biological control, plant-parasitic nematodes, predaceous mites, water agar

Procedia PDF Downloads 63