Search results for: clean hydrogen production

Authors: Ricardo Torcato, Helder Morais

Abstract:

The manufacture of crystal glass parts is based on obtaining the rough geometry by blowing and/or injection, generally followed by a set of manual finishing operations using cutting and grinding tools. The forming techniques used do not allow the obtainment, with repeatability, of parts with complex shapes and the finishing operations use intensive specialized labor resulting in high cycle times and production costs. This work aims to explore the digital manufacture of crystal glass parts by investigating new subtractive techniques for the automated, flexible finishing of these parts. Finishing operations are essential to respond to customer demands in terms of crystal feel and shine. It is intended to investigate the applicability of different computerized finishing technologies, namely milling and grinding in a CNC machining center with or without ultrasonic assistance, to crystal processing. Research in the field of grinding hard and brittle materials, despite not being extensive, has increased in recent years, and scientific knowledge about the machinability of crystal glass is still very limited. However, it can be said that the unique properties of glass, such as high hardness and very low toughness, make any glass machining technology a very challenging process. This work will measure the performance improvement brought about by the use of ultrasound compared to conventional crystal grinding. This presentation is focused on the mechanical characterization and analysis of the cutting forces in CNC machining of superior crystal glass (Pb ≥ 30%). For the mechanical characterization, the Vickers hardness test provides an estimate of the material hardness (Hv) and the fracture toughness based on cracks that appear in the indentation. Mechanical impulse excitation test estimates the Young’s Modulus, shear modulus and Poisson ratio of the material. For the cutting forces, it a dynamometer was used to measure the forces in the face grinding process. The tests were made based on the Taguchi method to correlate the input parameters (feed rate, tool rotation speed and depth of cut) with the output parameters (surface roughness and cutting forces) to optimize the process (better roughness using the cutting forces that do not compromise the material structure and the tool life) using ANOVA. This study was conducted for conventional grinding and for the ultrasonic grinding process with the same cutting tools. It was possible to determine the optimum cutting parameters for minimum cutting forces and for minimum surface roughness in both grinding processes. Ultrasonic-assisted grinding provides a better surface roughness than conventional grinding.

Keywords: CNC machining, crystal glass, cutting forces, hardness

Procedia PDF Downloads 155

Authors: Yuping Zhang, Teng Ma, Nadia Everaert, Hongfu Zhang

Abstract:

Supplying dietary fiber during gestation is known to improve the welfare of feed-restricted sows. However, whether high fiber supplementation during pregnancy can improve the performance of sows and their offspring depends on the type, amount, source, etc., in which the solubility plays a key important role. Insoluble fibers have been shown to increase feed intake of sows in lactation, meet the needs of sows for milk production, reduce sow’s weight and backfat loss, and thus improve the performance of sows and their offspring. In this study, we investigated the effect of the addition of fermented feed mulberry (FFM), rich in insoluble fiber, during the whole gestation on the performance of sows and their offspring and explored possible mechanisms by determining serum hormones and fecal microbiota. The FFM-diet contained 25.5% FFM (on dry matter basis) and was compared with the control–diet (CON, corn, and soybean meal diet). The insoluble fiber content of the FFM and CON diet are respectively 29.3% and 19.1%. both groups were allocated 20 multiparous sows, and they are fed different feed allowance to make sure all the sows get the same digestible energy for each day. After farrowing, all sows were fed the same lactation diet ad libitum. The serum estradiol, progesterone concentration, blood glucose, and insulin levels at gestation day 0, 20, and 60 were tested. And also, the composition and differences fecal microbiota at day 60 of gestation were analyzed. Fecal consistency was determined with Bristol stool scale method, those with a score below 3 were counted as constipation The results showed that there was no impact of the FFM treatment on sows’ backfat, bodyweight changes, blood glucose, serum estradiol, and progesterone concentration, litter size, and performance of the offspring(p > 0.05), Except significant decrease in the concentration of insulin in sows’ serum at 60 days of gestation were observed in the FFM group compare to the CON group (P < 0.01). FFM diet also significantly increased feed intake on the first, third, and 21st days of sow lactation. (p < 0.01); The α- and β- diversity and abundance of the microbiota were significant increased (p < 0.01) compared with the CON group, The abundance of Firmicutes and Bacteroidetes were significantly increased, meanwhile the abundances of Spirochetes, Proteobacteria, and Euryarchaeota, were significantly reduced in the feces of the FFM group. We also analyzed the fecal microbiota of constipated sows vs non-constipated sows and found that the diversity and abundance did also differ between these two groups. FFM and CON group < 0.01). The relationship between sow’s constipation and microbiota merits further investigation.

Keywords: fermented feed mulberry, reproductive performance, fecal flora, sow

Procedia PDF Downloads 155

Authors: J. H. Bang, H. J. Baek, K. I. Kim, B. J. Lee, H. J. Jung, H. J. Jang, S. K. Jung

Abstract:

Asthma is a chronic inflammatory lung disease characterized by airway hyper responsiveness (AHR), airway obstruction and airway wall remodeling responsible for significant morbidity and mortality worldwide. Genetic and environment factors may result in asthma, but there are no the exact causes of asthma. Chungpye-tang (CPT) has been prescribed as a representative aerosol agent for patients with dyspnea, cough and phlegm in the respiratory clinic at Kyung Hee Korean Medicine Hospital. This Korean herbal medicines have the effect of dispelling external pathogen and dampness pattern. CPT is composed of 4 species of herbal medicines. The 4 species of herbal medicines are Ephedrae herba, Pogostemonis(Agatachis) herba, Caryophylli flos and Zingiberis rhizoma crudus. CPT suppresses neutrophil infiltration and the production of pro-inflammatory cytokines in lipopolysaccharide (LPS)-induced acute lung injury (ALI) mouse model. Moreover, the anti-inflammatory effects of CPT on a mouse model of Chronic Obstructive Pulmonary Disease (COPD) was proved. Activation of the NF-κB has been proven that it plays an important role in inflammation via inducing transcription of pro-inflammatory genes. Over-expression of NF-κB has been believed be related to many inflammatory diseases such as arthritis, gastritis, asthma and COPD. So we firstly hypothesize whether CPT has an anti-inflammatory effect on asthmatic human airway epithelial tissue via inhibiting NF-κB pathway. In this study, CPT was extracted with distilled water for 3 hours at 100°C. After process of filtration and evaporation, it was freeze dried. And asthmatic human lung tissues were provided by MatTek Corp. We investigated the precise mechanism of the anti-inflammatory effect of CPT by western blotting analysis. We observed whether the decoction extracts could reduce NF-κB activation, COX-2 protein expression and NF-κB-mediated pro-inflammatory cytokines such as TNF-α, eotaxin, IL-4, IL-9 and IL-13 in asthmatic human lung tissue. As results of this study, there was a trend toward decreased NF-κB expression in asthmatic human airway epithelial tissue. We found that the inhibition effects of CPT on COX-2 expression was not determined. IL-9 and IL-13 secretion was significantly reduced in the asthmatic human lung tissue treated with CPT. Overall, our results indicate that CPT has an anti-inflammatory effect through blocking the signaling pathway of NF-κB, thereby CPT may be a potential remedial agent for allergic asthma.

Keywords: Chungpye-tang, allergic asthma, asthmatic human airway epithelial tissue, nuclear factor kappa B (NF-κB) pathway, COX-2

Procedia PDF Downloads 337

Authors: Sharib Ahmed, Mansoor Rafi, Kamran Ali Awan, Faraz Khaskhali, Amir Maqbool, Altaf Hashmi

Abstract:

Medical linear accelerators (LINAC’s) used in radiotherapy treatments produce undesired neutrons when they are operated at energies above 8 MeV, both in electron and photon configuration. Neutrons are produced by high-energy photons and electrons through electronuclear (e, n) a photonuclear giant dipole resonance (GDR) reactions. These reactions occurs when incoming photon or electron incident through the various materials of target, flattening filter, collimators, and other shielding components in LINAC’s structure. These neutrons may reach directly to the patient, or they may interact with the surrounding materials until they become thermalized. A work has been set up to study the effect of different parameter on the production of neutron around the room by photonuclear reactions induced by photons above ~8 MeV. One of the commercial available neutron detector (Ludlum Model 42-31H Neutron Detector) is used for the detection of thermal and fast neutrons (0.025 eV to approximately 12 MeV) inside and outside of the treatment room. Measurements were performed for different field sizes at 100 cm source to surface distance (SSD) of detector, at different distances from the isocenter and at the place of primary and secondary walls. Other measurements were performed at door and treatment console for the potential radiation safety concerns of the therapists who must walk in and out of the room for the treatments. Exposures have taken place from Elekta Synergy® linear accelerators for two different energies (10 MV and 18 MV) for a given 200 MU’s and dose rate of 600 MU per minute. Results indicates that neutron doses at 100 cm SSD depend on accelerator characteristics means jaw settings as jaws are made of high atomic number material so provides significant interaction of photons to produce neutrons, while doses at the place of larger distance from isocenter are strongly influenced by the treatment room geometry and backscattering from the walls cause a greater doses as compare to dose at 100 cm distance from isocenter. In the treatment room the ambient dose equivalent due to photons produced during decay of activation nuclei varies from 4.22 mSv.h−1 to 13.2 mSv.h−1 (at isocenter),6.21 mSv.h−1 to 29.2 mSv.h−1 (primary wall) and 8.73 mSv.h−1 to 37.2 mSv.h−1 (secondary wall) for 10 and 18 MV respectively. The ambient dose equivalent for neutrons at door is 5 μSv.h−1 to 2 μSv.h−1 while at treatment console room it is 2 μSv.h−1 to 0 μSv.h−1 for 10 and 18 MV respectively which shows that a 2 m thick and 5m longer concrete maze provides sufficient shielding for neutron at door as well as at treatment console for 10 and 18 MV photons.

Keywords: equivalent doses, neutron contamination, neutron detector, photon energy

Procedia PDF Downloads 449

Authors: V. Viliene, A. Raceviciute-Stupeliene, V. Sasyte, V. Slausgalvis, R. Gruzauskas, J. Al-Saifi

Abstract:

Animal nutritionists and scientists have searched for alternative measures to improve the production. One of such alternative is use of organic acids as feed additive in animal nutrition. The study was conducted to investigate the impact of butyric acids, calcium formate, organic acids, and its salts (BCOS) additives on rabbit’s productive performance, carcass traits and meat quality. The study was conducted with 14 Californian breed rabbits. The rabbits were assigned to two treatment groups (seven rabbits per each treatment group). The dietary treatments were 1) control diet, 2) diet supplemented with a mixture BCOS - 2 kg/t of feed. Growth performance characteristics (body weight, daily weight gain, daily feed intake, feed conversion ratio, mortality) were evaluated. Rabbits were slaughtered; carcass characteristics and meat quality were evaluated. Samples loin and hind leg meat were analysed to determine carcass characteristics, pH and colour measurements, cholesterol, and malonyldialdehyde (MDA) content in loin and hind leg meat. Differences between treatments were significant for body weight (1.30 vs. 1.36 kg; P<0.05), daily weight gain (16.60 vs. 17.85 g; P<0.05), and daily feed intake (78.25 vs. 80.58 g; P<0.05) for control and experimental group respectively for the entire experimental period (from 28–77 days old). No significant differences were found in feed conversion ratio and mortality. The feed additives insertion in the diets did not significantly influence the carcass yield or the proportions of the various carcass parts and organs. Differences between treatments were significant for pH value after 48h in loin (5.86 vs. 5.74; P<0.05), hind leg meat (6.62 vs. 6.65; P<0.05), more intense colour b* of loin (5.57 vs. 6.06; P<0.05), less intense colour a* (14.99 vs. 13.15; P<0.05) in hind leg meat. Cholesterol content in hind leg meat decreased by 17.67 mg/100g compared to control group (P<0.05). After storage for three months, MDA concentration decreased in loin and hind leg meat by 0.3 μmol/kg and 0.26 μmol/kg respectively compared to that of the control group (P<0.05). The results of this study suggest that BCOS could potentially be used in rabbit nutrition with consequent benefits on the rabbits’ productivity and nutritional quality of rabbit meat for consumers.

Keywords: butyric acids, Ca formate, meat quality, organic acids salts, rabbits, productivity

Procedia PDF Downloads 216

Authors: Saem Lee, Thanh Nguyen, Hio-Jung Shin, Thomas Koellner

Abstract:

Land-use management has an influence on the provision of ecosystem service in dynamic, agricultural landscapes. Agricultural land use is important for maintaining the productivity and sustainability of agricultural ecosystems. However, in Korea, intensive farming activities in this highland agricultural zone, the upper stream of Soyang has led to contaminated soil caused by over-use pesticides and fertilizers. This has led to decrease in water and soil quality, which has consequences for ecosystem services and human wellbeing. Conventional farming has still high percentage in this area and there is no special measure to prevent low water quality caused by farming activities. Therefore, the adoption of environmentally friendly farming has been considered one of the alternatives that lead to improved water quality and increase in biomass production. Concurrently, farm households with environmentally friendly farming have occupied still low rates. Therefore, our research involved a farm household survey spanning conventional farming, the farm in transition and organic farming in Soyang watershed. Another purpose of our research was to compare economic advantage of the farmers adopting environmentally friendly farming and non-adaptors and to investigate the different factors by logistic regression analysis with socio-economic and benefit-cost ratio variables. The results found that farmers with environmentally friendly farming tended to be younger than conventional farming and farmer in transition. They are similar in terms of gender which was predominately male. Farmers with environmentally friendly farming were more educated and had less farming experience than conventional farming and farmer in transition. Based on the benefit-cost analysis, total costs that farm in transition farmers spent for one year are about two times as much as the sum of costs in environmentally friendly farming. The benefit of organic farmers was assessed with 2,800 KRW per household per year. In logistic regression, the factors having statistical significance are subsidy and district, residence period and benefit-cost ratio. And district and residence period have the negative impact on the practice of environmentally friendly farming techniques. The results of our research make a valuable contribution to provide important information to describe Korean policy-making for agricultural and water management and to consider potential approaches to policy that would substantiate ways beneficial for sustainable resource management.

Keywords: organic farming, logistic regression, profitability, agricultural land-use

Procedia PDF Downloads 403

Authors: Asim Abbasi, Muhammad Sufyan, Iqra, Muhammad Ibrahim Shahid, Muhammad Ashfaq

Abstract:

The foundation of human life on earth relies on many ecosystem services provided by insects of which pollination owes a vital role. The pollination service offered by insects has annual worth of approximately €153 billion. The majority of the flowering plants depends on entomophiles pollination for their reproduction and formation of seeds and fruits. The quantity and quality of insect pollination have multiple implications for stable ecosystem, diverse species level, food security and climate change resilience. The rapidly mounting human population, depletion of natural resources and the global climate change forced us to enter an era of pollination crisis. Climate change not only alters the phenology, population abundance and geographic ranges of different pollinators but also hinders their pollination activities. The successful pollination process relies heavily on the synchronization of biological events of pollinators with the phenological stages of the flowering plants. However, there are possibilities that impending climatic changes may result in asynchrony between plant-pollinators interactions and also mitigate the extent of pollination. The trophic mismatch mostly occurs when pollinators and plants inhabiting the same environment use different environmental cues to regulate their biological events, as these cues are not equally affected by climate change. Synchrony has also been disrupted when one of the interacting species has migratory nature and depend on cues for migration. Moreover, irregular rainfalls and up-surging temperature also disrupts the foraging behaviour of pollinators resulting in reduced flowers visits by insect. Climate change has a direct impact on the behavior and physiology of honey bees, the best known pollinators owing to their extreme floral fidelity. Rising temperature not only alleviates the quantity and quality of floral environment but also alters the bee’s colony harvesting and development ability. Furthermore, a possible earlier decline of flowers is expected in a growing season due to this rising temperature. This may also lead to disrupt the efficiency bumblebee queen that require a constant and adequate nectar and pollen supply throughout the entire growing season for healthy colony production. Considering the role of insect pollination in our ecosystem, their associated risks regarding climate change should be addressed properly for devising a well-focused research needed for their conservation.

Keywords: climate change, phenological, pollination, synchronization

Procedia PDF Downloads 219

Authors: Chenxiao Yang, Li Li

Abstract:

In this decade, the sportswear market rapidly expanded while numerous sports brands are conducting fierce competitions to hold their market shares and trying to act as a leader in professional competition sports areas to set the trends. Thus, various advancing sports equipment is being deeply explored to improving athletes’ performance in fierce competitions. Although there is plenty protective equipment such as cuff, running legging, etc., on the market, there is still blank in the field of sportswear during prerace warm-up this important time gap, especially for those competitions host in cold environment. Because there is always time gaps between warm-up and race due to event logistics or unexpected weather factors. Athletes will be exposed to chilly condition for an unpredictable long period of time. As a consequence, the effects of warm-up will be negated, and the competition performance will be degraded. However, reviewing the current market, there is none effective sports equipment provided to help athletes against this harsh environment or the rare existing products are so blocky or heavy to restrict the actions. An ideal thermal-protective sportswear should be light, flexible, comfort and aesthetic at the same time. Therefore, this design research adopted the textile circular knitting methodology to integrate soft silver-coated conductive yarns (ab. SCCYs), elastic nylon yarn and polyester yarn to develop the proposed electrical, thermal sportswear, with the strengths aforementioned. Meanwhile, the relationship between heating performance, stretch load, and energy consumption were investigated. Further, a simulation model was established to ensure providing sufficient warm and flexibility at lower energy cost and with an optimized production, parameter determined. The proposed circular knitting technology and simulation model can be directly applied to instruct prototype developments to cater different target consumers’ needs and ensure prototypes’’ safety. On the other hand, high R&D investment and time consumption can be saved. Further, two prototypes: a kneecap and an elbow guard, were developed to facilitate the transformation of research technology into an industrial application and to give a hint on the blur future blueprint.

Keywords: cold environment, silver-coated conductive yarn, electrical thermal textile, stretchable

Procedia PDF Downloads 269

Authors: Elena Pummer, Holger Schuettrumpf

Abstract:

By today underground pumped storage plants as an outstanding alternative for classical pumped storage plants do not exist. They are needed to ensure the required balance between production and demand of energy. As a short to medium term storage pumped storage plants have been used economically over a long period of time, but their expansion is limited locally. The reasons are in particular the required topography and the extensive human land use. Through the use of underground reservoirs instead of surface lakes expansion options could be increased. Fulfilling the same functions, several hydrodynamic processes result in the specific design of the underground reservoirs and must be implemented in the planning process of such systems. A combined 3D numerical and experimental approach leads to currently unknown results about the occurring wave types and their behavior in dependence of different design and operating criteria. For the 3D numerical simulations, OpenFOAM was used and combined with an experimental approach in the laboratory of the Institute of Hydraulic Engineering and Water Resources Management at RWTH Aachen University, Germany. Using the finite-volume method and an explicit time discretization, a RANS-Simulation (k-ε) has been run. Convergence analyses for different time discretization, different meshes etc. and clear comparisons between both approaches lead to the result, that the numerical and experimental models can be combined and used as hybrid model. Undular bores partly with secondary waves and breaking bores occurred in the underground reservoir. Different water levels and discharges change the global effects, defined as the time-dependent average of the water level as well as the local processes, defined as the single, local hydrodynamic processes (water waves). Design criteria, like branches, directional changes, changes in cross-section or bottom slope, as well as changes in roughness have a great effect on the local processes, the global effects remain unaffected. Design calculations for underground pumped storage plants were developed on the basis of existing formulae and the results of the hybrid approach. Using the design calculations reservoirs heights as well as oscillation periods can be determined and lead to the knowledge of construction and operation possibilities of the plants. Consequently, future plants can be hydraulically optimized applying the design calculations on the local boundary conditions.

Keywords: energy storage, experimental approach, hybrid approach, undular and breaking Bores, 3D numerical approach

Procedia PDF Downloads 213

Authors: Brian Chi Yan Cheng, Hui Guo, Tao Su, Xiu‐qiong Fu, Ting Li, Zhi‐ling Yu

Abstract:

Rheumatoid arthritis (RA) affects around 1% of the globe population. Yet, there is still no cure for RA. Toll-like receptor 4 (TLR4) signalling has been found to be involved in the pathogenesis of RA, making it a potential therapeutic target for RA treatment. A herbal formula (RL) consisting of fruits of Rosa Multiflora (Eijitsu rose) and flowers of Lonicera Japonica (Japanese honeysuckle) has been used in treating various inflammatory disorders for more than a thousand year. Both of them are rich sources of nutrients and bioactive phytochemicals, which can be used in producing different food products and supplements. In this study, we would evaluate the anti-arthritic effect of RL on collagen-induced arthritis (CIA) in rats and investigate the involvement of TLR4 signaling in the mode of action of RL. Anti-arthritic efficacy was evaluated using CIA rats induced by bovine type II collagen. The treatment groups were treated with RL (82.5, 165, and 330 mg/kg bw per day, p.o.) or positive control indomethacin (0.25 mg/kg bw per day, p.o.) for 35 days. Clinical signs (hind paw volume and arthritis severity scores), changes in serum inflammatory mediators, pro-/antioxidant status, histological and radiographic changes of joints were investigated. Spleens and peritoneal macrophages were used to determine the effects of RL on innate and adaptive immune responses in CIA rats. The involvement of TLR4 signalling pathways in the anti-arthritic effect of RL was examined in cartilage tissue of CIA rats, murine RAW264.7 macrophages and human THP-1 monocytic cells. The severity of arthritis in the CIA rats was significantly attenuated by RL. Antioxidant status, histological score and radiographic score were efficiently improved by RL. RL could also dose-dependently inhibit pro-inflammatory cytokines in serum of CIA rats. RL significantly inhibited the production of various pro-inflammatory mediators, the expression and/or activity of the components of TLR4 signalling pathways in animal tissue and cell lines. RL possesses anti-arthritic effect on collagen-induced arthritis in rats. The therapeutic effect of RL may be related to its inhibition on pro-inflammatory cytokines in serum. The inhibition of the TAK1/NF-κB and TAK1/MAPK pathways participate in the anti-arthritic effects of RL. This provides a pharmacological justification for the dietary use of RL in the control of various arthritic diseases. Further investigation should be done to develop RL into a anti-arthritic food products and/or supplements.

Keywords: japanese honeysuckle, rheumatoid arthritis, rosa multiflora, rosehip

Procedia PDF Downloads 433

Authors: C. Brecher, M. Fey, F. Du Bois-Reymond, S. Neus

Abstract:

Additive manufacturing has emerged into a fast-growing section within the manufacturing technologies. Established machine tool manufacturers, such as DMG MORI, recently presented machine tools combining milling and laser welding. By this, machine tools can realize a higher degree of flexibility and a shorter production time. Still there are challenges that have to be accounted for in terms of maintaining the necessary machining accuracy - especially due to thermal effects arising through the use of high power laser processing units. To study the thermal behavior of laser-integrated machine tools, it is essential to analyze and simulate the thermal behavior of machine components, individual and assembled. This information will help to design a geometrically stable machine tool under the influence of high power laser processes. This paper presents an approach to decrease the loss of machining precision due to thermal impacts. Real effects of laser machining processes are considered and thus enable an optimized design of the machine tool, respective its components, in the early design phase. Core element of this approach is a matched FEM model considering all relevant variables arising, e.g. laser power, angle of laser beam, reflective coefficients and heat transfer coefficient. Hence, a systematic approach to obtain this matched FEM model is essential. Indicating the thermal behavior of structural components as well as predicting the laser beam path, to determine the relevant beam intensity on the structural components, there are the two constituent aspects of the method. To match the model both aspects of the method have to be combined and verified empirically. In this context, an essential machine component of a five axis machine tool, the turn-swivel table, serves as the demonstration object for the verification process. Therefore, a turn-swivel table test bench as well as an experimental set-up to measure the beam propagation were developed and are described in the paper. In addition to the empirical investigation, a simulative approach of the described types of experimental examination is presented. Concluding, it is shown that the method and a good understanding of the two core aspects, the thermo-elastic machine behavior and the laser beam path, as well as their combination helps designers to minimize the loss of precision in the early stages of the design phase.

Keywords: additive manufacturing, laser beam machining, machine tool, thermal effects

Procedia PDF Downloads 265

Authors: Ahmed S. Fayed, Umima M. Mansour

Abstract:

Three polyvinyl chloride membrane sensors were developed for the electrochemical evaluation of ferrous, manganese and zinc ions. The sensors were used for assaying metal ions in cervical mucus (CM) of Egyptian river buffalo-cows (Bubalus bubalis) as their levels vary dependent on cyclical hormone variation during different phases of estrus cycle. The presented sensors are based on using ionophores, β-cyclodextrin (β-CD), hydroxypropyl β-cyclodextrin (HP-β-CD) and sulfocalix-4-arene (SCAL) for sensors 1, 2 and 3 for Fe²⁺, Mn²⁺ and Zn²⁺, respectively. Dioctyl phthalate (DOP) was used as the plasticizer in a polymeric matrix of polyvinylchloride (PVC). For increasing the selectivity and sensitivity of the sensors, each sensor was enriched with a suitable complexing agent, which enhanced the sensor’s response. For sensor 1, β-CD was mixed with bathophenanthroline; for sensor 2, porphyrin was incorporated with HP-β-CD; while for sensor 3, oxine was the used complexing agent with SCAL. Linear responses of 10^-7-10^-2 M with cationic slopes of 53.46, 45.01 and 50.96 over pH range 4-8 were obtained using coated graphite sensors for ferrous, manganese and zinc ionic solutions, respectively. The three sensors were validated, according to the IUPAC guidelines. The obtained results by the presented potentiometric procedures were statistically analyzed and compared with those obtained by atomic absorption spectrophotometric method (AAS). No significant differences for either accuracy or precision were observed between the two techniques. Successful application for the determination of the three studied cations in CM, for the purpose to determine the proper time for artificial insemination (AI) was achieved. The results were compared with those obtained upon analyzing the samples by AAS. Proper detection of estrus and correct time of AI was necessary to maximize the production of buffaloes. In this experiment, 30 multi-parous buffalo-cows were in second to third lactation and weighting 415-530 kg, and were synchronized with OVSynch protocol. Samples were taken in three times around ovulation, on day 8 of OVSynch protocol, on day 9 (20 h before AI) and on day 10 (1 h before AI). Beside analysis of trace elements (Fe²⁺, Mn²⁺ and Zn²⁺) in CM using the three sensors, the samples were analyzed for the three cations and also Cu²⁺ by AAS in the CM samples and blood samples. The results obtained were correlated with hormonal analysis of serum samples and ultrasonography for the purpose of determining of the optimum time of AI. The results showed significant differences and powerful correlation with Zn²⁺ composition of CM during heat phase and the ovulation time, indicating that the parameter could be used as a tool to decide optimal time of AI in buffalo-cows.

Keywords: PVC Sensors, buffalo-cows, cyclodextrins, atomic absorption spectrophotometry, artificial insemination, OVSynch protocol

Procedia PDF Downloads 219

Authors: Tanima Chatterjee, Maitree Bhattacharyya

Abstract:

The global challenge of type 2 diabetes mellitus is a major health concern in this millennium, and researchers are continuously exploring new targets to develop a novel therapeutic strategy. Type 2 diabetes mellitus (T2DM) is often coupled with dyslipidemia increasing the risks for cardiovascular (CVD) complications. Enhanced oxidative and nitrosative stresses appear to be the major risk factors underlying insulin resistance, dyslipidemia, β-cell dysfunction, and T2DM pathogenesis. Autophagy emerges to be a promising defense mechanism against stress-mediated cell damage regulating tissue homeostasis, cellular quality control, and energy production, promoting cell survival. In this study, we have attempted to explore the pivotal role of autophagy in T2DM subjects with or without dyslipidemia in peripheral blood mononuclear cells and insulin-resistant HepG2 cells utilizing flow cytometric platform, confocal microscopy, and molecular biology techniques like western blotting, immunofluorescence, and real-time polymerase chain reaction. In the case of T2DM with dyslipidemia higher population of autophagy, positive cells were detected compared to patients with the only T2DM, which might have resulted due to higher stress. Autophagy was observed to be triggered both by oxidative and nitrosative stress revealing a novel finding of our research. LC3 puncta was observed in peripheral blood mononuclear cells and periphery of HepG2 cells in the case of the diabetic and diabetic-dyslipidemic conditions. Increased expression of ATG5, LC3B, and Beclin supports the autophagic pathway in both PBMC and insulin-resistant Hep G2 cells. Upon blocking autophagy by 3-methyl adenine (3MA), the apoptotic cell population increased significantly, as observed by caspase‐3 cleavage and reduced expression of Bcl2. Autophagy has also been evidenced to control oxidative stress-mediated up-regulation of inflammatory markers like IL-6 and TNF-α. To conclude, this study elucidates autophagy to play a protective role in the case of diabetes mellitus with dyslipidemia. In the present scenario, this study demands to have a significant impact on developing a new therapeutic strategy for diabetic dyslipidemic subjects by enhancing autophagic activity.

Keywords: autophagy, apoptosis, dyslipidemia, reactive oxygen species, reactive nitrogen species, Type 2 diabetes

Procedia PDF Downloads 131

Authors: Sana Rezig, Yosr Ben Mlik, Mounir Jaouadi, Foued Khoffi, Slah Msahli, Bernard Durand

Abstract:

Increasing interest in environmental concerns, natural fibers are once again being considered as reinforcements for polymer composites. The main objective of this study is to explore another natural resource, Typha fiber; which is renewable without production cost and available abundantly in nature. The aim of this study was to study the flexural properties of composite resin with and without reinforcing Typha leaf and stem fibers. The specimens were made by the hand-lay-up process using polyester matrix. In our work, we focused on the effect of various treatment conditions (sea water, alkali treatment and a combination of the two treatments), as a surface modifier, on the flexural properties of the Typha fibers reinforced polyester composites. Moreover, weight ratio of Typha leaf or stem fibers was investigated. Besides, both fibers from leaf and stem of Typha plant were used to evaluate the reinforcing effect. Another parameter, which is reinforcement structure, was investigated. In fact, a first composite was made with air-laid nonwoven structure of fibers. A second composite was with a mixture of fibers and resin for each kind of treatment. Results show that alkali treatment and combined process provided better mechanical properties of composites in comparison with fiber treated by sea water. The fiber weight ratio influenced the flexural properties of composites. Indeed, a maximum value of flexural strength of 69.8 and 62,32 MPa with flexural modulus of 6.16 and 6.34 GPawas observed respectively for composite reinforced with leaf and stem fibers for 12.6 % fiber weight ratio. For the different treatments carried out, the treatment using caustic soda, whether alone or after retting seawater, show the best results because it improves adhesion between the polyester matrix and the fibers of reinforcement. SEM photographs were made to ascertain the effects of the surface treatment of the fibers. By varying the structure of the fibers of Typha, the reinforcement used in bulk shows more effective results as that used in the non-woven structure. In addition, flexural strength rises with about (65.32 %) in the case of composite reinforced with a mixture of 12.6% leaf fibers and (27.45 %) in the case of a composite reinforced with a nonwoven structure of 12.6 % of leaf fibers. Thus, to better evaluate the effect of the fiber origin, the reinforcing structure, the processing performed and the reinforcement factor on the performance of composite materials, a statistical study was performed using Minitab. Thus, ANOVA was used, and the patterns of the main effects of these parameters and interaction between them were established. Statistical analysis, the fiber treatment and reinforcement structure seem to be the most significant parameters.

Keywords: flexural properties, fiber treatment, structure and weight ratio, SEM photographs, Typha leaf and stem fibers

Procedia PDF Downloads 417

Authors: T. Elrazaz

Abstract:

This paper examines accrual and real earnings management by publicly listed targets around mergers and acquisitions. Prior literature shows that earnings management around mergers and acquisitions can have a significant economic impact because of the associated wealth transfers among stakeholders. More importantly, acting on behalf of their shareholders or pursuing their self-interests, managers of both targets and acquirers may be equally motivated to manipulate earnings prior to an acquisition to generate higher gains for their shareholders or themselves. Building on the grounds of information asymmetry, agency conflicts, stewardship theory, and the revelation principle, this study addresses the question of whether takeover targets employ accrual and real earnings management in the periods prior to the announcement of Mergers and Acquisitions (M&A). Additionally, this study examines whether acquirers are able to detect targets’ earnings management, and in response, adjust the acquisition premium paid in order not to face the risk of overpayment. This study uses an aggregate accruals approach in estimating accrual earnings management as proxied by estimated abnormal accruals. Additionally, real earnings management is proxied for by employing widely used models in accounting and finance literature. The results of this study indicate that takeover targets manipulate their earnings using accruals in the second year with an earnings release prior to the announcement of the M&A. Moreover, in partitioning the sample of targets according to the method of payment used in the deal, the results are restricted only to targets of stock-financed deals. These results are consistent with the argument that targets of cash-only or mixed-payment deals do not have the same strong motivations to manage their earnings as their stock-financed deals counterparts do additionally supporting the findings of prior studies that the method of payment in takeovers is value relevant. The findings of this study also indicate that takeover targets manipulate earnings upwards through cutting discretionary expenses the year prior to the acquisition while they do not do so by manipulating sales or production costs. Moreover, in partitioning the sample of targets according to the method of payment used in the deal, the results are restricted only to targets of stock-financed deals, providing further robustness to the results derived under the accrual-based models. Finally, this study finds evidence suggesting that acquirers are fully aware of the accrual-based techniques employed by takeover targets and can unveil such manipulation practices. These results are robust to alternative accrual and real earnings management proxies, as well as controlling for the method of payment in the deal.

Keywords: accrual earnings management, acquisition premium, real earnings management, takeover targets

Procedia PDF Downloads 117

Authors: Temple Probyne Abali

Abstract:

Port Harcourt, Rivers State in the Niger Delta region of Nigeria is bedeviled by the phenomenon of climatechange, posing threat to food security and livelihood. This study examined a 4 decadel (1980-2020) trend of climate change as well as its socio-economic impact on food security in the region. Furthermore, to achieve sustainable food security and livelihood amidst the phenomenon, the study adopted the World Bank Assisted Third National Fadama Development Programme approach. The data source for climate change involved secondary data from Nigeria Meteorological Agency (NIMET). Consequently, the results for climate change over the 4decade period were displayed in tables, charts and maps for the expected changes. Data sources on socio-economic impact of food security and livelihood were acquired through questionnairedesign. A purposive random sampling technique was used in selecting 5 coastal communities inthe region known for viable economic potentials for agricultural development and the resultswere analyzed using Analysis of Variance (ANOVA). The Participatory Rural Appraisal (PRA) technique of the World Bank for needs assessment wasadopted in selecting 5 agricultural sub-project proposals/activities based on groups’ commoneconomic interest from a total of 1,000 farmers each drawn from the 5 communities of differentage groups including men, women, youths and the vulnerable. Based on the farmers’ sub-projectinterests, the various groups’ Strength, Weakness, Opportunities and Threats (SWOT), Problem Listing Matrix, Skill Gap Analysis as well as EIAson their sub-project proposals/activities were analyzed with substantialMonitoring and Evaluation (M & E), using the Specific, Measurable, Attribute, Reliable and Time bound (SMART)approach. Based on the findings from the PRA technique, the farmers recorded considerableincreaseinincomeofover200%withinthe5yearprojectplan(2008-2013).Thestudyrecommends capacity building and advisory services on this PRA innovation. By so doing, there would be a sustainable increase in agricultural production and assured food security in an environmental friendly manner, in line with the United Nation’s Sustainable Development Goals(SDGs).

Keywords: climate change, food security, fadama, world bank, agriculture, sdgs

Procedia PDF Downloads 93

Authors: Elenice Maria Schons Silva, Andre Carlos Silva

Abstract:

The crescent demand for raw material has increased mining activities. Mineral industry faces the challenge of process more complexes ores, with very small particles and low grade, together with constant pressure to reduce production costs and environment impacts. Froth flotation deserves special attention among the concentration methods for mineral processing. Besides its great selectivity for different minerals, flotation is a high efficient method to process fine particles. The process is based on the minerals surficial physicochemical properties and the separation is only possible with the aid of chemicals such as collectors, frothers, modifiers, and depressants. In order to use sustainable and eco-friendly reagents, oils extracted from three different vegetable species (pequi’s pulp, macauba’s nut and pulp, and Jatropha curcas) were studied and tested as apatite collectors. Since the oils are not soluble in water, an alkaline hydrolysis (or saponification), was necessary before their contact with the minerals. The saponification was performed at room temperature. The tests with the new collectors were carried out at pH 9 and Flotigam 5806, a synthetic mix of fatty acids industrially adopted as apatite collector manufactured by Clariant, was used as benchmark. In order to find a feasible replacement for cornstarch the flour and starch of a graniferous variety of sorghum was tested as depressant. Apatite samples were used in the flotation tests. XRF (X-ray fluorescence), XRD (X-ray diffraction), and SEM/EDS (Scanning Electron Microscopy with Energy Dispersive Spectroscopy) were used to characterize the apatite samples. Zeta potential measurements were performed in the pH range from 3.5 to 12.5. A commercial cornstarch was used as depressant benchmark. Four depressants dosages and pH values were tested. A statistical test was used to verify the pH, dosage, and starch type influence on the minerals recoveries. For dosages equal or higher than 7.5 mg/L, pequi oil recovered almost all apatite particles. In one hand, macauba’s pulp oil showed excellent results for all dosages, with more than 90% of apatite recovery, but in the other hand, with the nut oil, the higher recovery found was around 84%. Jatropha curcas oil was the second best oil tested and more than 90% of the apatite particles were recovered for the dosage of 7.5 mg/L. Regarding the depressant, the lower apatite recovery with sorghum starch were found for a dosage of 1,200 g/t and pH 11, resulting in a recovery of 1.99%. The apatite recovery for the same conditions as 1.40% for sorghum flour (approximately 30% lower). When comparing with cornstarch at the same conditions sorghum flour produced an apatite recovery 91% lower.

Keywords: collectors, depressants, flotation, mineral processing

Procedia PDF Downloads 153

Authors: Damtew Samson Zerihun

Abstract:

This paper primarily describes the concept of a hierarchical safety control (HSC) in discrete manufacturing to up-hold productivity with human intervention and machine failures using a systematic approach, through increasing the system availability and using additional knowledge on machines so as to improve the human machine collaboration (HMC). It also highlights the implemented PLC safety algorithm, in applying this generic concept to a concrete pro-duction line using a lab demonstrator called FATIE (Factory Automation Test and Integration Environment). Furthermore, the paper describes a model and provide a systematic representation of human-machine collabora-tion in discrete manufacturing and to this end, the Hierarchical Safety Control concept is proposed. This offers a ge-neric description of human-machine collaboration based on Finite State Machines (FSM) that can be applied to vari-ous discrete manufacturing lines instead of using ad-hoc solutions for each line. With its reusability, flexibility, and extendibility, the Hierarchical Safety Control scheme allows upholding productivity while maintaining safety with reduced engineering effort compared to existing solutions. The approach to the solution begins with a successful partitioning of different zones around the Integrated Manufacturing System (IMS), which are defined by operator tasks and the risk assessment, used to describe the location of the human operator and thus to identify the related po-tential hazards and trigger the corresponding safety functions to mitigate it. This includes selective reduced speed zones and stop zones, and in addition with the hierarchical safety control scheme and advanced safety functions such as safe standstill and safe reduced speed are used to achieve the main goals in improving the safe Human Ma-chine Collaboration and increasing the productivity. In a sample scenarios, It is shown that an increase of productivity in the order of 2.5% is already possible with a hi-erarchical safety control, which consequently under a given assumptions, a total sum of 213 € could be saved for each intervention, compared to a protective stop reaction. Thereby the loss is reduced by 22.8%, if occasional haz-ard can be refined in a hierarchical way. Furthermore, production downtime due to temporary unavailability of safety devices can be avoided with safety failover that can save millions per year. Moreover, the paper highlights the proof of the development, implementation and application of the concept on the lab demonstrator (FATIE), where it is realized on the new safety PLCs, Drive Units, HMI as well as Safety devices in addition to the main components of the IMS.

Keywords: discrete automation, hierarchical safety controller, human machine collaboration, programmable logical controller

Procedia PDF Downloads 369

Authors: Nino Damenia

Abstract:

The paper discusses the risks arising in agriculture in Georgia, the possibilities of their acceptance and prevention, the threat created by the pandemic crisis, and the state programs for overcoming them. The share of agriculture in the country's GDP is 8.3%. Over the past five years, Georgia has imported $ 5.9 billion worth of agri-food products. Despite these figures, agriculture has become an important sector for the Georgian government since 2012, as evidenced by the more than 1.5 billion GEL spent from the 2012-2020 budget for agricultural development. Any field of agriculture, be it poultry, livestock, cereals, fruits, or vegetables, is very sensitive to various climatic and viral risks. Avoiding these risks requires additional investment. It is noteworthy that small farms are mainly affected by the risks, while relatively large farms face fewer problems because they are relatively prepared to face the problems and can avoid them more easily. An example of viral risk in the article is the export of hazelnuts, which has quite a lot of potential. Due to the spoilage of the crop caused by Brown Marmorated Stink Bug (BMSB), hazelnut exports have declined considerably over the years. If the volume of hazelnuts exported in 2016 was 179 378 thousand USD, due to the deficit caused by Brown Marmorated Stink Bug (BMSB) in 2018, it became 57 124 thousand USD. And after the situation was relatively settled, hazelnut seedlings were poisoned. By 2020, this figure improved to 91,088 thousand US dollars. The development of the agricultural sector and the reduction of risks require technological development, investor interest, and even more state support to enable more small farms to have the potential for greater production and sustainable development. The aim of the study is to identify the risks arising in the agricultural sector of Georgia before and after the pandemic, to evaluate them, compare them with the agriculture of some European countries, and to develop the necessary recommendations to avoid the emerging risks. The research uses methods of analysis and synthesis, observation, induction, deduction, and analysis of statistics. The paper is based on both Georgian and foreign scientific research, as well as state-published documentation on agricultural assistance programs. The research is based on the analysis of data published by the European Statistics Office, the National Statistics Office of Georgia, and many other organizations. The results of the study and the recommendations will help reduce the risks in agriculture in Georgia and, in general, to identify the existing potential and the development of the sector as a whole.

Keywords: risk, agriculture, pandemi, brown marmorated stink bug (BMSB)

Procedia PDF Downloads 121

Authors: Oksana Domkina

Abstract:

According to the modern economic theory, human capital became one of the main production factors and the most promising direction of investment, as such investment provides opportunity of obtaining high and long-term economic and social effects. Informational technology (IT) sector is the representative of this new economy which is most dependent on human capital as the main competitive factor. So the question for this sector is not whether investment in development of personal should be made, but what are the most effective ways of executing it and who has to pay for the education: Worker, company or government. In this paper we examine the IT sector, describe the labor market of IT workers and its development, and analyze the risks that IT companies may face if they invest in the development of their workers and what factors influence it. The main problem and difficulty of quantitative estimation of risk of investment in human capital of a company and its forecasting is human factor. Human behavior is often unpredictable and complex, so it requires specific approaches and methods of assessment. To build a comprehensive method of estimation of the risk of investment in human capital of a company considering human factor, we decided to use the method of analytic hierarchy process (AHP), that initially was created and developed. We separated three main group of factors: Risks related to the worker, related to the company, and external factors. To receive data for our research, we conducted a survey among the HR departments of Ukrainian IT companies used them as experts for the AHP method. Received results showed that IT companies mostly invest in the development of their workers, although several hire only already qualified personnel. According to the results, the most significant risks are the risk of ineffective training and the risk of non-investment that are both related to the firm. The analysis of risk factors related to the employee showed that, the factors of personal reasons, motivation, and work performance have almost the same weights of importance. Regarding internal factors of the company, there is a high role of the factor of compensation and benefits, factors of interesting projects, team, and career opportunities. As for the external environment, one of the most dangerous factor of risk is competitor activities, meanwhile the political and economical situation factor also has a relatively high weight, which is easy to explain by the influence of severe crisis in Ukraine during 2014-2015. The presented method allows to take into consideration all main factors that affect the risk of investment in human capital of a company. This gives a base for further research in this field and allows for a creation of a practical framework for making decisions regarding the personnel development strategy and specific employees' development plans for the HR departments.

Keywords: risks, personnel development, investment in development, factors of risk, risk of investment in development, IT, analytic hierarchy process, AHP

Procedia PDF Downloads 301

Authors: Obaid AlOtaibi, Salman Hussain

Abstract:

Wind energy is associated with many geographical factors including wind speed, climate change, surface topography, environmental impacts, and several economic factors, most notably the advancement of wind technology and energy prices. It is the fastest-growing and least economically expensive method for generating electricity. Wind energy generation is directly related to the characteristics of spatial wind. Therefore, the feasibility study for the wind energy conversion system is based on the value of the energy obtained relative to the initial investment and the cost of operation and maintenance. In Kuwait, wind energy is an appropriate choice as a source of energy generation. It can be used in groundwater extraction in agricultural areas such as Al-Abdali in the north and Al-Wafra in the south, or in fresh and brackish groundwater fields or remote and isolated locations such as border areas and projects away from conventional power electricity services, to take advantage of alternative energy, reduce pollutants, and reduce energy production costs. The study covers the State of Kuwait with an exception of metropolitan area. Climatic data were attained through the readings of eight distributed monitoring stations affiliated with Kuwait Institute for Scientific Research (KISR). The data were used to assess the daily, monthly, quarterly, and annual available wind energy accessible for utilization. The researchers applied the Suitability Model to analyze the study by using the ArcGIS program. It is a model of spatial analysis that compares more than one location based on grading weights to choose the most suitable one. The study criteria are: the average annual wind speed, land use, topography of land, distance from the main road networks, urban areas. According to the previous criteria, the four proposed locations to establish wind farm projects are selected based on the weights of the degree of suitability (excellent, good, average, and poor). The percentage of areas that represents the most suitable locations with an excellent rank (4) is 8% of Kuwait’s area. It is relatively distributed as follows: Al-Shqaya, Al-Dabdeba, Al-Salmi (5.22%), Al-Abdali (1.22%), Umm al-Hayman (0.70%), North Wafra and Al-Shaqeeq (0.86%). The study recommends to decision-makers to consider the proposed location (No.1), (Al-Shqaya, Al-Dabdaba, and Al-Salmi) as the most suitable location for future development of wind farms in Kuwait, this location is economically feasible.

Keywords: Kuwait, renewable energy, spatial analysis, wind energy

Procedia PDF Downloads 151

Authors: Michal Pravenec, Miroslava Simakova, Jan Silhavy

Abstract:

Brown adipose tissue (BAT) plays an important role in lipid and glucose metabolism in rodents and possibly also in humans. Recently, using systems genetics approach in the BAT from BXH/HXB recombinant inbred strains, derived from the SHR (spontaneously hypertensive rat) and BN (Brown Norway) progenitors, we identified Cd36 (fatty acid translocase) as the hub gene of co-expression module associated with BAT relative weight and function. An important aspect of BAT biology is to better understand the mechanisms regulating the uptake and utilization of fatty acids and glucose. Accordingly, BAT function in the SHR that harbors mutant nonfunctional Cd36 variant (hereafter referred to as SHR-Cd36⁻/⁻) was compared with SHR transgenic line expressing wild type Cd36 under control of a universal promoter (hereafter referred to as SHR-Cd36⁺/⁺). BAT was incubated in media containing insulin and 14C-U-glucose alone or 14C-U-glucose together with palmitate. Incorporation of glucose into BAT lipids was significantly higher in SHR-Cd36⁺/⁺ versus SHR-Cd36⁻/⁻ rats when incubation media contained glucose alone (SHR-Cd36⁻/⁻ 591 ± 75 vs. SHR-Cd36⁺/⁺ 1036 ± 135 nmol/gl./2h; P < 0.005). Adding palmitate into incubation media had no effect in SHR-Cd36⁻/⁻ rats but significantly reduced glucose incorporation into BAT lipids in SHR-Cd36⁺/⁺ (SHR-Cd36⁻/⁻ 543 ± 55 vs. SHR-Cd36⁺/⁺ 766 ± 75 nmol/gl./2h; P < 0.05 denotes significant Cd36 x palmitate interaction determined by two-way ANOVA). This Cd36-dependent reduced glucose uptake in SHR-Cd36⁺/⁺ BAT was likely secondary to increased palmitate incorporation and utilization due to the presence of wild type Cd36 fatty acid translocase in transgenic rats. This possibility is supported by increased incorporation of 14C-U-palmitate into BAT lipids in the presence of both palmitate and glucose in incubation media (palmitate alone: SHR-Cd36⁻/⁻ 870 ± 21 vs. SHR-Cd36⁺/⁺ 899 ± 42; glucose+palmitate: SHR-Cd36⁻/⁻ 899 ± 47 vs. SHR-Cd36⁺/⁺ 1460 ± 111 nmol/palm./2h; P < 0.05 denotes significant Cd36 x glucose interaction determined by two-way ANOVA). It is possible that addition of glucose into the incubation media increased palmitate incorporation into BAT lipids in SHR-Cd36⁺/⁺ rats because of glucose availability for glycerol phosphate production and increased triglyceride synthesis. These changes in glucose and palmitate incorporation into BAT lipids were associated with significant differential expression of Irs1, Irs2, Slc2a4 and Foxo1 genes involved in insulin signaling and glucose metabolism only in SHR-Cd36⁺/⁺ rats which suggests Cd36-dependent effects on insulin action. In conclusion, these results provide compelling evidence that Cd36 plays an important role in BAT insulin signaling and energy substrate utilization.

Keywords: brown adipose tissue, Cd36, energy substrate utilization, insulin signaling, spontaneously hypertensive rat

Procedia PDF Downloads 140

Authors: Hela Ayeb Mrabtini, Ghazi Bellakhal, Jamel Chahed

Abstract:

The presence of the dispersed phase in gas-liquid bubbly flow considerably alters the liquid turbulence. The bubbles induce turbulent fluctuations that enhance the global liquid turbulence level and alter the mechanisms of turbulence. RANS modeling of uniformly sheared flows on an isolated sphere centered in a control volume is performed using first and second order turbulence closures. The sphere is placed in the production-dissipation equilibrium zone where the liquid velocity is set equal to the relative velocity of the bubbles. The void fraction is determined by the ratio between the sphere volume and the control volume. The analysis of the turbulence statistics on the control volume provides numerical results that are interpreted with regard to the effect of the bubbles wakes on the turbulence structure in uniformly sheared bubbly flow. We assumed for this purpose that at low void fraction where there is no hydrodynamic interaction between the bubbles, the single-phase flow simulation on an isolated sphere is representative on statistical average of a sphere network. The numerical simulations were firstly validated against the experimental data of bubbly homogeneous turbulence with constant shear and then extended to produce numerical results for a wide range of shear rates from 0 to 10 s^-1. These results are compared with our turbulence closure proposed for gas-liquid bubbly flows. In this closure, the turbulent stress tensor in the liquid is split into a turbulent dissipative part produced by the gradient of the mean velocity which also contains the turbulence generated in the bubble wakes and a pseudo-turbulent non-dissipative part induced by the bubbles displacements. Each part is determined by a specific transport equation. The simulations of uniformly sheared flows on an isolated sphere reproduce the mechanisms related to the turbulent part, and the numerical results are in perfect accordance with the modeling of the transport equation of the turbulent part. The reduction of second order turbulence closure provides a description of the modification of turbulence structure by the bubbles presence using a dimensionless number expressed in terms of two-time scales characterizing the turbulence induced by the shear and that induced by bubbles displacements. The numerical simulations carried out in the framework of a comprehensive analysis reproduce particularly the attenuation of the turbulent friction showed in the experimental results of bubbly homogeneous turbulence subjected to a constant shear.

Keywords: gas-liquid bubbly flows, homogeneous turbulence, turbulence closure, uniform shear

Procedia PDF Downloads 463

Authors: Janine Just, Kerstin Meints

Abstract:

The research aims to compare vocabulary size and grammatical development between US American English- and British English-speaking children at age 2;0. As there is evidence that precocious children with large vocabularies develop grammar skills earlier than their typically developing peers, it was investigated if this also holds true across varieties of English. Thus, if US American children start to produce words earlier than their British counterparts, this could mean that US children are also at an advantage in the early developmental stages of acquiring grammar. This research employs a British English adaptation of the MacArthur-Bates CDI Words and Sentences (Lincoln Toddler CDI) to compare vocabulary and also grammar scores with the updated US Toddler CDI norms. At first, the Lincoln TCDI was assessed for its concurrent validity with the Preschool Language Scale (PLS-5 UK). This showed high correlations for the vocabulary and grammar subscales between the tests. In addition, the frequency of the Toddler CDI’s words was also compared using American and British English corpora of adult spoken and written language. A paired-samples t-test found a significant difference in word frequency between the British and the American CDI demonstrating that the TCDI’s words were indeed of higher frequency in British English. We then compared language and grammar scores between US (N = 135) and British children (N = 96). A two-way between groups ANOVA examined if the two samples differed in terms of SES (i.e. maternal education) by investigating the impact of SES and country on vocabulary and sentence complexity. The two samples did not differ in terms of maternal education as the interaction effects between SES and country were not significant. In most cases, scores were not significantly different between US and British children, for example, for overall word production and most grammatical subscales (i.e. use of words, over- regularizations, complex sentences, word combinations). However, in-depth analysis showed that US children were significantly better than British children at using some noun categories (i.e. people, objects, places) and several categories marking early grammatical development (i.e. pronouns, prepositions, quantifiers, helping words). However, the effect sizes were small. Significant differences for grammar were found for irregular word forms and progressive tense suffixes. US children were more advanced in their use of these grammatical categories, but the effect sizes were small. In sum, while differences exist in terms of vocabulary and grammar ability, favouring US children, effect sizes were small. It can be concluded that most British children are ‘catching up’ with their US American peers at age 2;0. Implications of this research will be discussed.

Keywords: first language acquisition, grammar, parent report instrument, vocabulary

Procedia PDF Downloads 283

Authors: Alberto A. Escobar Puentes, G. Adriana García, Luis F. Cuevas G., Alejandro P. Zepeda, Fernando B. Martínez, Susana A. Rincón

Abstract:

Snack foods are usually classified as ‘junk food’ because have little nutritional value. However, due to the increase on the demand and third generation (3G) snacks market, low price and easy to prepare, can be considered as carriers of compounds with certain nutritional value. Resistant starch (RS) is classified as a prebiotic fiber it helps to control metabolic problems and has anti-cancer colon properties. The active compound can be developed by chemical cross-linking of starch with phosphate salts to obtain a type 4 resistant starch (RS4). The chemical reaction can be achieved by extrusion, a process widely used to produce snack foods, since it's versatile and a low-cost procedure. Starch is the major ingredient for snacks 3G manufacture, and the seeds of sorghum contain high levels of starch (70%), the most drought-tolerant gluten-free cereal. Due to this, the aim of this research was to develop a snack (3G), with RS4 in optimal conditions extrusion (previously determined) from sorghum starch, and carry on a sensory, chemically and structural characterization. A sample (200 g) of sorghum starch was conditioned with 4% sodium trimetaphosphate/ sodium tripolyphosphate (99:1) and set to 28.5% of moisture content. Then, the sample was processed in a single screw extruder equipped with rectangular die. The inlet, transport and output temperatures were 60°C, 134°C and 70°C, respectively. The resulting pellets were expanded in a microwave oven. The expansion index (EI), penetration force (PF) and sensory analysis were evaluated in the expanded pellets. The pellets were milled to obtain flour and RS content, degree of substitution (DS), and percentage of phosphorus (% P) were measured. Spectroscopy [Fourier Transform Infrared (FTIR)], X-ray diffraction, differential scanning calorimetry (DSC) and scanning electron microscopy (SEM) analysis were performed in order to determine structural changes after the process. The results in 3G were as follows: RS, 17.14 ± 0.29%; EI, 5.66 ± 0.35 and PF, 5.73 ± 0.15 (N). Groups of phosphate were identified in the starch molecule by FTIR: DS, 0.024 ± 0.003 and %P, 0.35±0.15 [values permitted as food additives (<4 %P)]. In this work an increase of the gelatinization temperature after the crosslinking of starch was detected; the loss of granular and vapor bubbles after expansion were observed by SEM; By using X-ray diffraction, loss of crystallinity was observed after extrusion process. Finally, a snack (3G) was obtained with RS4 developed by extrusion technology. The sorghum starch was efficient for snack 3G production.

Keywords: extrusion, resistant starch, snack (3G), Sorghum

Procedia PDF Downloads 312

Authors: Kunal Bhardwaj, Christine Browne

Abstract:

With the increase in global awareness of the environmental impacts of plastic-based products, there has been a massive drive to reduce our use of these products. Use of plastic-based substrates in electronic circuits has been a matter of concern recently. Plastics provide a very smooth and cheap surface for printing high-performance electronics due to their non-permeability to ink and easy mouldability. In this research, we explore the use of nano cellulose (NC) films in electronics as they provide an advantage of being 100% recyclable and eco-friendly. The main hindrance in the mass adoption of NC film as a substitute for plastic is its higher surface roughness which leads to ink penetration, and dispersion in the channels on the film. This research was conducted to tune the RMS roughness of NC films to a range where they can replace plastics in electronics(310-470nm). We studied the dependence of the surface roughness of the NC film on the following tunable aspects: 1) composition by weight of the NC suspension that is sprayed on a silicon wafer 2) the width and the depth of the channels on the silicon wafer used as a base. Various silicon wafers with channel depths ranging from 6 to 18 um and channel widths ranging from 5 to 500um were used as a base. Spray coating method for NC film production was used and two solutions namely, 1.5wt% NC and a 50-50 NC-CNC (cellulose nanocrystal) mixture in distilled water, were sprayed through a Wagner sprayer system model 117 at an angle of 90 degrees. The silicon wafer was kept on a conveyor moving at a velocity of 1.3+-0.1 cm/sec. Once the suspension was uniformly sprayed, the mould was left to dry in an oven at 50°C overnight. The images of the films were taken with the help of an optical profilometer, Olympus OLS 5000. These images were converted into a ‘.lext’ format and analyzed using Gwyddion, a data and image analysis software. Lowest measured RMS roughness of 291nm was with a 50-50 CNC-NC mixture, sprayed on a silicon wafer with a channel width of 5 µm and a channel depth of 12 µm. Surface roughness values of 320+-17nm were achieved at lower (5 to 10 µm) channel widths on a silicon wafer. This research opened the possibility of the usage of 100% recyclable NC films with an additive (50% CNC) in high-performance electronics. Possibility of using additives like Carboxymethyl Cellulose (CMC) is also being explored due to the hypothesis that CMC would reduce friction amongst fibers, which in turn would lead to better conformations amongst the NC fibers. CMC addition would thus be able to help tune the surface roughness of the NC film to an even greater extent in future.

Keywords: nano cellulose films, electronic circuits, nanocrystals and surface roughness

Procedia PDF Downloads 124

Authors: Mukhammad Fatkhullah, Ayla Karina Budita, Cut Rizka Al Usrah, Kanita Khoirun Nisa, Muhammad Alhada Fuadilah Habib, Siti Muslihatul Mukaromah

Abstract:

Batik industry has become one of the leading industries in the economy of Indonesia. Since the recognition of batik as one of cultural wealth and national identity of Indonesia by UNESCO, batik production keeps increasing as a result of increasing demands for batik, whether from domestically or abroad. One of the rapid development batik industries in Indonesia is batik industry in Lawean Village, Solo, Central Java, Indonesia. This batik industry generally uses putting-out system where batik workers work in their own houses. With the implementation of this system, therefore employers don’t have to prepare Environmental Impact Analysis (EIA), social security for workers, overtime payment, space for working, and equipment for working. The implementation of putting-out system causes many problems, starting from environmental pollution, the loss of social rights of workers, and even exploitation of workers by batik entrepreneurs. The data used to describe this reality is the primary data from qualitative research with in-depth interview data collection technique. Informants were determined purposively. The theory used to perform data interpretation is the phenomenology of Alfred Schutz. Both qualitative and phenomenology are used in this study to describe batik workers exploitation in terms of the implementation of putting-out system on home batik industry in Lawean. The research result showed that workers in batik industry sector in Lawean were exploited with the implementation of putting-out system. The workers were strictly employed by the entrepreneurs, so that their job cannot be called 'part-time' job anymore. In terms of labor and time, the workers often work more than 12 hours per day and they often work overtime without receiving any overtime payment. In terms of work safety, the workers often have contact with chemical substances contained in batik making materials without using any protection, such as clothes work, which is worsened by the lack of standard or procedure in work that can cause physical damage, such as burnt and peeled off skin. Moreover, exposure and contamination of chemical materials make the workers and their families vulnerable to various diseases. Meanwhile, batik entrepreneurs did not give any social security (including health cost aid). Besides that, the researchers found that batik industry in home industry sector is not environmentally friendly, even damaging ecosystem because industrial waste disposed without EIA.

Keywords: exploitation, home batik industry, occupational health and safety, putting-out system

Procedia PDF Downloads 319

Authors: Tingting Song

Abstract:

Wetlands are significant ecosystems that provide a variety of ecosystem services for humans, such as, providing water and food resources, purifying water quality, regulating climate, protecting biodiversity, and providing cultural, recreational, and educational resources. Wetlands also provide benefits, such as reduction of flood, storm damage, and soil erosion. The flood protection ecosystem services of wetlands are often ignored. Due to climate change, the flood caused by extreme weather in recent years occur frequently. Flood has a great impact on people's production and life with more and more economic losses. This study area is in the Tone river basin in the Kanto area, Japan. It is the second-longest river with the largest basin area in Japan, and it is still suffering heavy economic losses from floods. Tone river basin is one of the rivers that provide water for Tokyo and has an important impact on economic activities in Japan. The purpose of this study was to investigate land-use changes of wetlands in the Tone River Basin, and whether there are spatial differences in the value of wetland functions in mitigating economic losses caused by floods. This study analyzed the land-use change of wetland in Tone River, based on the Landsat data from 1980 to 2020. Combined with flood economic loss, wetland area, GDP, population density, and other social-economic data, a geospatial weighted regression model was constructed to analyze the spatial difference of wetland ecosystem service value. Now, flood protection mainly relies on such a hard project of dam and reservoir, but excessive dependence on hard engineering will cause the government huge financial pressure and have a big impact on the ecological environment. However, natural wetlands can also play a role in flood management, at the same time they can also provide diverse ecosystem services. Moreover, the construction and maintenance cost of natural wetlands is lower than that of hard engineering. Although it is not easy to say which is more effective in terms of flood management. When the marginal value of a wetland is greater than the economic loss caused by flood per unit area, it may be considered to rely on the flood storage capacity of the wetland to reduce the impact of the flood. It can promote the sustainable development of wetlands ecosystem. On the other hand, spatial analysis of wetland values can provide a more effective strategy for flood management in the Tone river basin.

Keywords: wetland, geospatial weighted regression, ecosystem services, environment valuation

Procedia PDF Downloads 102

Authors: Lori Lioce, Gary Maddux, Norven Goddard, Ishella Fogle, Bernard Schroer

Abstract:

This paper presents the integration of technologies into nursing education. The collaborative effort includes the College of Nursing (CoN) at the University of Alabama in Huntsville (UAH) and the UAH Systems Management and Production Center (SMAP). The faculty at the CoN conducts needs assessments to identify education and training requirements. A team of CoN faculty and SMAP engineers then prioritize these requirements and establish improvement/development teams. The development teams consist of nurses to evaluate the models and to provide feedback and of undergraduate engineering students and their senior staff mentors from SMAP. The SMAP engineering staff develops and creates the physical models using 3D printing, silicone molds and specialized molding mixtures and techniques. The collaboration has focused on developing teaching and training, or clinical, simulators. In addition, the onset of the Covid-19 pandemic has intensified this relationship, as 3D modeling shifted to supplied personal protection equipment (PPE) to local health care providers. A secondary collaboration has been introducing students to clinical benchmarking through the UAH Center for Management and Economic Research. As a result of these successful collaborations the Model Exchange & Development of Nursing & Engineering Technology (MEDNET) has been established. MEDNET seeks to extend and expand the linkage between engineering and nursing to K-12 schools, technical schools and medical facilities in the region to the resources available from the CoN and SMAP. As an example, stereolithography (STL) files of the 3D printed models, along with the specifications to fabricate models, are available on the MEDNET website. Ten 3D printed models have been developed and are currently in use by the CoN. The following additional training simulators are currently under development:1) suture pads, 2) gelatin wound models and 3) printed wound tattoos. Specification sheets have been written for these simulations that describe the use, fabrication procedures and parts list. These specifications are available for viewing and download on MEDNET. Included in this paper are 1) descriptions of CoN, SMAP and MEDNET, 2) collaborative process used in product improvement/development, 3) 3D printed models of training and teaching simulators, 4) training simulators under development with specification sheets, 5) family care practice benchmarking, 6) integrating the simulators into the nursing curriculum, 7) utilizing MEDNET as a pandemic response, and 8) conclusions and lessons learned.

Keywords: 3D printing, nursing education, simulation, trainers

Procedia PDF Downloads 122

Authors: W. Mohammedsaeed, A. J. Mcbain, S. M. Cruickshank, C. A. O’Neill

Abstract:

Many studies have demonstrated the importance of probiotics and their potential therapeutic effects within the gut. Recently, the possible therapeutic effects of probiotics in other tissues have also begun to be investigated. Comparatively few studies have evaluated the use of topical probiotics in relation to the skin. In this study, we have conducted preliminary investigations into whether a well-known probiotic, Lactobacillus rhamnosus GG (LGG), can increase the rate of re-epithelialization in a model wound. Full-thickness skin was obtained from individuals undergoing elective cosmetic surgery. This skin was wounded using excisional punch and cultured using a serum-free medium, either in the presence or absence of L. rhamnosus GG lysate. Histological staining of the sections was performed with Haematoxylin& Eosin E to quantify “epithelial tongue length”. This is the length of the new epithelial ‘tongue’ that grows and covers the exposed dermis at the inner wound edges. The length of the new epithelial ‘tongue’ was compared in untreated section and section treated with and L. rhamnosus GG made using108CFU/ml bacterial cells. L. rhamnosus GG lysate enhanced significantly the re-epithelialisation of treated wounds compared with that of untreated wounds (P=0.005, n=3). Tongue length, at day 1 was 7.55μm 0.15, at day 3 it was 18.5μm 0.25 and at day 7 was 22.9μm 0.35. These results can be compared with untreated cultures in which tongue length was 3.25μm 0.35, day 3 was 9.65μm 0.25 and day 7 was 13.5μm 0.15 post-wounding. In ex-vivo proliferation and migration cells were measured by determining the expression of nuclear proliferation marker Ki-67 and the expression of Phosphorylated cortactin respectively demonstrated that L. rhamnosus GG significantly increased NHEK proliferation and migration rates relative to controls. However, the dominant mechanism was migration because in ex-vivo skin treated with the L. rhamnosus GG up-regulated the gene expression of the chemokine receptor and ligands CXCR2 and CXCL2 comparing with controls (P=0.02, P=0.03 respectively, n=3). High levels of CXCL2/CXCL2 have already been implicated in multiple aspects of stimulation of wound healing through activation of keratinocyte migration. These data demonstrate that lysates from Lactobacillus rhamnosus GG increase re-epithelialization by stimulation of keratinocyte migration. The current study identifies the partial mechanism that contribute to stimulating the wound-healing process ex vivo in response to L. rhamnosus GG lysate is an increase in the production of CXCL2/ CXCR2 in ex vivo models. The use of probiotic lysates potentially offers new options to develop treatments that could improve wound healing.

Keywords: Lactobacillus rhamnosus GG, wounds, migration, lysate

Procedia PDF Downloads 329