Search results for: functionally graded dielectric elastomer

Authors: S. Kozlovski, S.W. Feigelson, R. Alon

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The b2 integrin ligands ICAM-1 ICAM-2 and the endothelial VLA-4 integrin ligand VCAM-1 are constitutively expressed on different lung vessels and on high endothelial venules (HEVs), the main portal for lymphocyte entry from the blood into lung draining lymph nodes. ICAMs are also ubiquitously expressed by many antigen-presenting leukocytes and have been traditionally suggested as critical for the various antigen-specific immune synapses generated by these distinct leukocytes and specific naïve and effector T cells. Loss of both ICAM-1 and ICAM-2 on the lung vasculature reduces the ability to patrol monocytes and Tregs to patrol the lung vasculature at a steady state. Our new findings suggest, however, that in terms of innate leukocyte trafficking into the lung lamina propria, both constitutively expressed and virus-induced vascular VCAM-1 can functionally compensate for the loss of these ICAMs. In a mouse model for influenza infection, neutrophil and NK cell recruitment and clearance of influenza remained normal in mice deficient in both ICAMs. Strikingly, mice deficient in both ICAMs also mounted normal influenza-specific CD8 proliferation and differentiation. In addition, these mice normally combated secondary influenza infection, indicating that the presence of ICAMs on conventional dendritic cells (cDCs) that present viral antigens are not required for immune synapse formation between these APCs and naïve CD8 T cells as previously suggested. Furthermore, long-lasting humoral responses critical for protection from a secondary homosubtypic influenza infection were also normal in mice deficient in both ICAM-1 and ICAM-2. Collectively, our results suggest that the expression of ICAM-1 and ICAM-2 on lung endothelial and epithelial cells, as well as on DCs and B cells, is not critical for the generation of innate or adaptive anti-viral immunity in the lungs. Our findings also suggest that endothelial VCAM-1 can substitute for the functions of vascular ICAMs in leukocyte trafficking into various lung compartments.

Keywords: emigration, ICAM-1, lymph nodes, VCAM-1

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Authors: Eduardo Antonio Lozano Hernandez, Nancy Ramirez Alvarez, Lorena Margarita Rios Mendoza, Jose Vinicio Macias Zamora, Felix Augusto Hernandez Guzman, Jose Luis Sanchez Osorio

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Microplastics (MPs) are one of the most numerous reported wastes found in the marine ecosystem, representing one of the greatest risks for organisms that inhabit that environment due to their bioavailability. Such is the case of bivalve mollusks, since they are capable of filtering large volumes of water, which increases the risk of contamination by microplastics through the continuous exposure to these materials. This study aims to determine, quantify and characterize microplastics found in the cultured oyster Crassostrea gigas. We also analyzed if there are spatio-temporal differences in the microplastic concentration of organisms grown in two bays having quite different human population. In addition, we wanted to have an idea of the possible impact on humans via consumption of these organisms. Commercial size organisms (>6cm length; n = 15) were collected by triplicate from eight oyster farming sites in Baja California, Mexico during winter and summer. Two sites are located in Todos Santos Bay (TSB), while the other six are located in San Quintin Bay (SQB). Site selection was based on commercial concessions for oyster farming in each bay. The organisms were chemically digested with 30% KOH (w/v) and 30% H₂O₂ (v/v) to remove the organic matter and subsequently filtered using a GF/D filter. All particles considered as possible MPs were quantified according to their physical characteristics using a stereoscopic microscope. The type of synthetic polymer was determined using a FTIR-ATR microscope and using a user as well as a commercial reference library (Nicolet iN10 Thermo Scientific, Inc.) of IR spectra of plastic polymers (with a certainty ≥70% for polymers pure; ≥50% for composite polymers). Plastic microfibers were found in all the samples analyzed. However, a low incidence of MP fragments was observed in our study (approximately 9%). The synthetic polymers identified were mainly polyester and polyacrylonitrile. In addition, polyethylene, polypropylene, polystyrene, nylon, and T. elastomer. On average, the content of microplastics in organisms were higher in TSB (0.05 ± 0.01 plastic particles (pp)/g of wet weight) than found in SQB (0.02 ± 0.004 pp/g of wet weight) in the winter period. The highest concentration of MPs found in TSB coincides with the rainy season in the region, which increases the runoff from streams and wastewater discharges to the bay, as well as the larger population pressure (> 500,000 inhabitants). Otherwise, SQB is a mainly rural location, where surface runoff from streams is minimal and in addition, does not have a wastewater discharge into the bay. During the summer, no significant differences (Manne-Whitney U test; P=0.484) were observed in the concentration of MPs found in the cultured oysters of TSB and SQB, (average: 0.01 ± 0.003 pp/g and 0.01 ± 0.002 pp/g, respectively). Finally, we concluded that the consumption of oyster does not represent a risk for humans due to the low concentrations of MPs found. The concentration of MPs is influenced by the variables such as temporality, circulations dynamics of the bay and existing demographic pressure.

Keywords: FTIR-ATR, Human risk, Microplastic, Oyster

Procedia PDF Downloads 154

Authors: Sara Santos, Cristina Saraiva, Sónia Saraiva

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The objective of this study was to evaluate the welfare of reared broilers using scoring systems at the slaughterhouse. The welfare of broilers from 70 different flocks was assessed in three different slaughterhouses, regarding 373043 animals, although not in equal proportions in each slaughterhouse due to the difference in the amount of flocks slaughtered per day because of different company size. Twenty-one flocks were evaluated in slaughterhouse A (30%), thirty in slaughterhouse B (42,9%) and nineteen in slaughterhouse C (27,1%). The parameters evaluated were feather cleanness, foot pad dermatitis, hock burn, breast burn and causes of carcass condemnation. Feather cleanness was scored into three classes: 0=clean; 1=moderately dirty and 2=dirty feathers. Foot pad dermatitis, hock burn and breast ulcer were graded in three classes: 0=no lesions, 1=moderate lesions and 2=severe lesions. Causes of carcass condemnation were divided into emaciation, ascites, colour alteration and febrile state, arthritis, aerosaculitis, dermatitis, peritonitis, myositis, cellulitis, extensive trauma and technopathies as mechanical trauma, insufficient bleeding and deficient plucking. Broilers evaluated had a body weight ranging between 0,909kg and 2,588kg (median 1,522kg) and age between 25 days and 45 days (median 33 days). Rejection rate of flocks ranged between 0,1% and 10,48% (median 1,4029%) and footpad dermatitis total score between 2 and 197, resulting in 20 flocks presenting moderate lesions and 15 flocks with severe lesions. Moderate hock burn was associated with severe foot pad dermatitis and with breast burn. The associations between these lesions suggest that the development of contact dermatitis is caused by a common cause, the prolonged contact with litter of poor quality. In conclusion, contact dermatitis lesions, mostly foot pad dermatitis, feather hygiene conditions and rejection rate were the main restrictions of good welfare and considered important indicators for the follow-up on the farm conditions.

Keywords: broiler, dermatitis, welfare, slaughterhouse

Procedia PDF Downloads 108

Authors: M. Cabuk, M. Yavuz, T. A. Yesil, H. I. Unal

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Electrorheological (ER) fluids are a class of smart materials exhibiting reversible changes in their rheological and mechanical properties under an applied electric field (E). ER fluids generally are composed of polarisable solid particles dispersed in non-conducting oil. ER fluids are fluids which exhibit. The resistance to motion of the ER fluid can be controlled by adjusting the applied E, due to their fast and reversible changes in their rheological properties presence of E. In this study, a series of chitosan/expanded perlite (CS/EP) composites with different chitosan mass fractions (10%, 20%, and 50%) was used. Characterizations of the composites were carried out by Fourier Transform Infrared (FTIR), X-ray diffraction (XRD) and Scanning electron microscopy with energy dispersive X-ray spectroscopy (SEM-EDX) techniques. Antisedimentation stability and dielectric properties of the composites were also determined. The effects of volume fraction, electric field strength, shear rate, shear stress, and temperature onto ER properties of the CS/EP composite particles dispersed in silicone oil (SO) were investigated in detail. Vibration damping behavior of the CS/EP composites were determined as a function of frequence, storage (Gʹ) and loss (Gʹ ʹ) moduli. It was observed that ER response of the CS/EP/SO ER fluids increased with increasing electric field strength and exhibited the typical shear thinning non-Newtonian viscoelastic behaviors with increasing shear rate. The maximum yield stress was obtained with 1250 Pa under E = 3 kV/mm. Further, the CS/EP/SO ER fluids were observed to sensitive to vibration control by showing reversible viscosity enhancements (Gʹ > Gʹ ʹ). Acknowledgements: The authors thank the TÜBİTAK (214Z199) for the financial support of this work.

Keywords: chitosan, electrorheology, perlite, vibration control

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Authors: Suprit Pradhan, Tshering Yangzom

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Even with availability of the modern day online insulation diagnostic technologies like partial discharge monitoring, the measurements like Dissipation Factor (tanδ), DC High Voltage Insulation Currents, Polarization Index (PI) and Insulation Resistance Measurements are still widely used as a diagnostic tools to assess the condition of stator insulation in hydro power plants. To evaluate the condition of stator winding insulation in one of the generators that have been operated since 1999, diagnostic tests were performed on the stator bars of 15 MVA generators of Basochhu Hydropower Plant. This paper presents diagnostic study done on the data gathered from the measurements which were performed in 2015 and 2016 as part of regular maintenance as since its commissioning no proper aging data were maintained. Measurement results of Dissipation Factor, DC High Potential tests and Polarization Index are discussed with regard to their effectiveness in assessing the ageing condition of the stator insulation. After a brief review of the theoretical background, the strengths of each diagnostic method in detecting symptoms of insulation deterioration are identified. The interesting results observed from Basochhu Hydropower Plant is taken into consideration to conclude that Polarization Index and DC High Voltage Insulation current measurements are best suited for the detection of humidity and contamination problems and Dissipation Factor measurement is a robust indicator of long-term ageing caused by oxidative degradation.

Keywords: dissipation Factor (tanδ), polarization Index (PI), DC High Voltage Insulation Current, insulation resistance (IR), Tan Delta Tip-Up, dielectric absorption ratio

Procedia PDF Downloads 290

Authors: Ahmed Atwa, Ashraf Hafez, Mohamed Abdelhameed, Adel Nabeeh, Mohamed Dawaba, Tamer Helmy

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Introduction and Objective: Tumour staging and grading do not usually reflect the future behavior of Wilms' tumor (WT) regarding mortality. Therefore, in this study, P53, Ki67 and cyclin A immunohistochemistry were used in a trial to predict WT cancer-specific survival (CSS). Methods: In this nonconcurrent cohort study, patients' archived data, including age at presentation, gender, history, clinical examination and radiological investigations, were retrieved then the patients were reviewed at the outpatient clinic of a tertiary care center by history-taking, clinical examination and radiological investigations to detect the oncological outcome. Cases that received preoperative chemotherapy or died due to causes other than WT were excluded. Formalin-fixed, paraffin-embedded specimens obtained from the previously preserved blocks at the pathology laboratory were taken on positively charged slides for IHC with p53, Ki67 and cyclin A. All specimens were examined by an experienced histopathologist devoted to the urological practice and blinded to the patient's clinical findings. P53 and cyclin A staining were scored as 0 (no nuclear staining),1 (<10% nuclear staining), 2 (10-50% nuclear staining) and 3 (>50% nuclear staining). Ki67 proliferation index (PI) was graded as low, borderline and high. Results: Of the 75 cases, 40 (53.3%) were males and 35 (46.7%) were females, and the median age was 36 months (2-216). With a mean follow-up of 78.6±31 months, cancer-specific mortality (CSM) occurred in 15 (20%) and 11 (14.7%) patients, respectively. Kaplan-Meier curve was used for survival analysis, and groups were compared using the Log-rank test. Multivariate logistic regression and Cox regression were not used because only one variable (cyclin A) had shown statistical significance (P=.02), whereas the other significant factor (residual tumor) had few cases. Conclusions: Cyclin A IHC should be considered as a marker for the prediction of WT CSS. Prospective studies with a larger sample size are needed.

Keywords: wilms’ tumour, nephroblastoma, urology, survival

Procedia PDF Downloads 51

Authors: Igor P. Maximkin, Arkady A. Yukhimchuk, Victor V. Baluev, Igor L. Malkov, Rafael K. Musyaev, Damir T. Sitdikov, Alexey V. Buchirin, Vasily V. Tikhonov

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Minimization of tritium diffusion leakage when developing devices handling tritium-containing media is key problems whose solution will at least allow essential enhancement of radiation safety and minimization of diffusion losses of expensive tritium. One of the ways to solve this problem is to use Al₂O₃ high-strength non-porous ceramics as a structural material of the bed body. This alumina ceramics offers high strength characteristics, but its main advantages are low hydrogen permeability (as against the used structural material) and high dielectric properties. The latter enables direct induction heating of an hydride-forming metal without essential heating of the pressure and containment vessel. The use of alumina ceramics and induction heating allows: - essential reduction of tritium extraction time; - several orders reduction of tritium diffusion leakage; - more complete extraction of tritium from metal hydrides due to its higher heating up to melting in the event of final disposal of the device. The paper presents computational and experimental results for the tritium bed designed to absorb 6 liters of tritium. Titanium was used as hydrogen isotope sorbent. Results of hydrogen realize kinetic from hydride-forming metal, strength and cyclic service life tests are reported. Recommendations are also provided for the practical use of the given bed type.

Keywords: aluminum oxide ceramic, hydrogen pressure, hydrogen isotope storage, titanium hydride

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Authors: Ehsan Mehryaar, Seyed Armin Motahari Tabari

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Coarse-grained soils are known and commonly used in a wide range of geotechnical projects, including high earth dams or embankments for their high shear strength. The most important engineering property of these soils is friction angle which represents the interlocking between soil particles and can be applied widely in designing and constructing these earth structures. Friction angle and dilative behavior of coarse-grained soils can be estimated from empirical correlations with in-situ testing and physical properties of the soil or measured directly in the laboratory performing direct shear or triaxial tests. Unfortunately, large-scale testing is difficult, challenging, and expensive and is not possible in most soil mechanic laboratories. So, it is common to remove the large particles and do the tests, which cannot be counted as an exact estimation of the parameters and behavior of the original soil. This paper describes a new methodology to simulate particles grading distribution of a well-graded gravel sample to a smaller scale sample as it can be tested in an ordinary direct shear apparatus to estimate the stress-strain behavior, friction angle, and dilative behavior of the original coarse-grained soil considering its confining pressure, and relative density using a machine learning method. A total number of 72 direct shear tests are performed in 6 different sizes, 3 different confining pressures, and 4 different relative densities. Multivariate Adaptive Regression Spline (MARS) technique was used to develop an equation in order to predict shear strength and dilative behavior based on the size distribution of coarse-grained soil particles. Also, an uncertainty analysis was performed in order to examine the reliability of the proposed equation.

Keywords: MARS, coarse-grained soil, shear strength, uncertainty analysis

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Authors: R. Khenata, T. Djied, R. Ahmed, H. Baltache, S. Bin-Omran, A. Bouhemadou

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We predict structural, phase transition as well as opto-electronic properties of the filled-tetrahedral (Nowotny-Juza) NaZnAs compound in this study. Calculations are carried out by employing the full potential (FP) linearized augmented plane wave (LAPW) plus local orbitals (lo) scheme developed within the structure of density functional theory (DFT). Exchange-correlation energy/potential (EXC/VXC) functional is treated using Perdew-Burke and Ernzerhof (PBE) parameterization for generalized gradient approximation (GGA). In addition to Trans-Blaha (TB) modified Becke-Johnson (mBJ) potential is incorporated to get better precision for optoelectronic properties. Geometry optimization is carried out to obtain the reliable results of the total energy as well as other structural parameters for each phase of NaZnAs compound. Order of the structural transitions as a function of pressure is found as: Cu2Sb type → β → α phase in our study. Our calculated electronic energy band structures for all structural phases at the level of PBE-GGA as well as mBJ potential point out; NaZnAs compound is a direct (Γ–Γ) band gap semiconductor material. However, as compared to PBE-GGA, mBJ potential approximation reproduces higher values of fundamental band gap. Regarding the optical properties, calculations of real and imaginary parts of the dielectric function, refractive index, reflectivity coefficient, absorption coefficient and energy loss-function spectra are performed over a photon energy ranging from 0.0 to 30.0 eV by polarizing incident radiation in parallel to both [100] and [001] crystalline directions.

Keywords: NaZnAs, FP-LAPW+lo, structural properties, phase transition, electronic band-structure, optical properties

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Authors: Liyang Yue, Bing Yan, James N. Monks, Rakesh Dhama, Zengbo Wang, Oleg V. Minin, Igor V. Minin

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A particle can function as a refractive lens to focus a plane wave, generating a narrow, high intensive, weak-diverging beam within a sub-wavelength volume, known as the ‘photonic jet’. Refractive index contrast (particle to background media) and scaling effect of the dielectric particle (relative-to-wavelength size) play key roles in photonic jet formation, rather than the shape of particle-lens. Waist (full width of half maximum, FWHM) of a photonic jet could be beyond the diffraction limit and smaller than the Airy disk, which defines the minimum distance between two objects to be imaged as two instead of one. Many important applications for imaging and sensing have been afforded based upon the super-resolution characteristic of the photonic jet. It is known that apodization method, in the form of an amplitude pupil-mask centrally situated on a particle-lens, can further reduce the waist of a photonic nanojet, however, usually lower its intensity at the focus due to blocking of the incident light. In this paper, the anomalously intensity-enhanced apodization effect was discovered in the near-field via numerical simulation. It was also experimentally verified by a scale model using a copper-masked Teflon cuboid solid immersion lens (SIL) with 22 mm side length under radiation of a plane wave with 8 mm wavelength. Peak intensity enhancement and the lateral resolution of the produced photonic jet increased by about 36.0 % and 36.4 % in this approach, respectively. This phenomenon may possess the scale effect and would be valid in multiple frequency bands.

Keywords: apodization, particle-lens, scattering, near-field optics

Procedia PDF Downloads 167

Authors: Juan-Pedro Rica-Peromingo

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Teachers constantly need to innovate and redefine materials for their lectures, especially in areas such as Language for Specific Purposes (LSP) and Translation Studies (TS). It is therefore essential for the lecturers to be technically skilled to handle the never-ending evolution in software and technology, which are necessary elements especially in certain courses at university level. This need becomes even more evident in Audiovisual Translation (AVT) Modules and Courses. AVT has undergone considerable growth in the area of teaching and learning of languages for academic purposes. We have witnessed the development of a considerable number of masters and postgraduate courses where AVT becomes a tool for L2 learning. The teaching and learning of different AVT modes are components of undergraduate and postgraduate courses. Universities, in which AVT is offered as part of their teaching programme or training, make use of professional or free software programs. This paper presents an approach in AVT withina specific university context, in which technology is used by means of professional and nonprofessional software. Students take an AVT subject as part of their English Linguistics Master’s Degree at the Complutense University (UCM) in which they are using professional (Spot) and nonprofessional (Subtitle Workshop, Aegisub, Windows Movie Maker) software packages. The students are encouraged to develop their tasks and projects simulating authentic professional experiences and contexts in the different AVT modes: subtitling for hearing and deaf and hard of hearing population, audio description and dubbing. Selected scenes from TV series such as X-Files, Gossip girl, IT Crowd; extracts from movies: Finding Nemo, Good Will Hunting, School of Rock, Harry Potter, Up; and short movies (Vincent) were used. Hence, the complexity of the audiovisual materials used in class as well as the activities for their projects were graded. The assessment of the diverse tasks carried out by all the students are expected to provide some insights into the best way to improve their linguistic accuracy and oral and written productions with the use of different AVT modes in a very specific ESP university context.

Keywords: ESP, audiovisual translation, technology, university teaching, teaching

Procedia PDF Downloads 502

Authors: Ananya Gupta, Sangeeta Bhaskar

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Mycobacterium indicus pranii (MIP) is a saprophytic mycobacterium. It is a predecessor of M. avium complex (MAC). Whole genome analysis and growth kinetics studies have placed MIP in between pathogenic and non-pathogenic species. It shares significant antigenic repertoire with M. tuberculosis and have unique immunomodulatory properties. MIP provides better protection than BCG against pulmonary tuberculosis in animal models. Immunization with MIP by aerosol route provides significantly higher protection as compared to immunization by subcutaneous (s.c.) route. However, mechanism behind differential protection has not been studied. In this study, using mice model we have evaluated and compared the M.tb specific immune response in lung compartments (airway lumen / lung interstitium) as well as spleen following MIP immunization via nasal (i.n.) and s.c. route. MIP i.n. vaccination resulted in increased seeding of memory T cells (CD4+ and CD8+ T-cells) in the airway lumen. Frequency of CD4+ T cells expressing Th1 migratory marker (CXCR3) and activation marker (CD69) were also high in airway lumen of MIP i.n. group. Significantly high ex vivo secretion of cytokines- IFN-, IL-12, IL-17 and TNF- from cells of airway luminal spaces provides evidence of antigen-specific lung immune response, besides generating systemic immunity comparable to MIP s.c. group. Analysis of T cell response on per cell basis revealed that antigen specific T-cells of MIP i.n. group were functionally superior as higher percentage of these cells simultaneously secreted IFN-gamma, IL-2 and TNF-alpha cytokines as compared to MIP s.c. group. T-cells secreting more than one of the cytokines simultaneously are believed to have robust effector response and crucial for protection, compared with single cytokine secreting T-cells. Adoptive transfer of airway luminal T-cells from MIP i.n. group into trachea of naive B6 mice revealed that MIP induced CD8 T-cells play crucial role in providing long term protection. Thus the study demonstrates that MIP intranasal vaccination induces M.tb specific memory T-cells in the airway lumen that results in an early and robust recall response against M.tb infection.

Keywords: airway lumen, Mycobacterium indicus pranii, Th1 migratory markers, vaccination

Procedia PDF Downloads 172

Authors: S. Cichosz, A. Masek

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A new cellulose hybrid modification approach, which is undoubtedly a scientific novelty, is introduced. The study reports the properties of cellulose (Arbocel UFC100 – Ultra Fine Cellulose) and characterizes cellulose filled polymer composites based on an ethylene-norbornene copolymer (TOPAS Elastomer E-140). Moreover, the approach of physicochemical two-stage cellulose treatment is introduced: solvent exchange (to ethanol or hexane) and further chemical modification with maleic anhydride (MA). Furthermore, the impact of the drying process on cellulose properties was investigated. Suitable measurements were carried out to characterize cellulose fibers: spectroscopic investigation (Fourier Transform Infrared Spektrofotometer-FTIR, Near InfraRed spectroscopy-NIR), thermal analysis (Differential scanning calorimetry, Thermal gravimetric analysis ) and Karl Fischer titration. It should be emphasized that for all UFC100 treatments carried out, a decrease in moisture content was evidenced. FT-IR reveals a drop in absorption band intensity at 3334 cm-1, the peak is associated with both –OH moieties and water. Similar results were obtained with Karl Fischer titration. Based on the results obtained, it may be claimed that the employment of ethanol contributes greatly to the lowering of cellulose water absorption ability (decrease of moisture content to approximately 1.65%). Additionally, regarding polymer composite properties, crucial data has been obtained from the mechanical and thermal analysis. The highest material performance was noted in the case of the composite sample that contained cellulose modified with MA after a solvent exchange with ethanol. This specimen exhibited sufficient tensile strength, which is almost the same as that of the neat polymer matrix – in the region of 40 MPa. Moreover, both the Payne effect and filler efficiency factor, calculated based on dynamic mechanical analysis (DMA), reveal the possibility of the filler having a reinforcing nature. What is also interesting is that, according to the Payne effect results, fibers dried before the further chemical modification are assumed to allow more regular filler structure development in the polymer matrix (Payne effect maximum at 1.60 MPa), compared with those not dried (Payne effect in the range 0.84-1.26 MPa). Furthermore, taking into consideration the data gathered from DSC and TGA, higher thermal stability is obtained in case of the materials filled with fibers that were dried before the carried out treatments (degradation activation energy in the region of 195 kJ/mol) in comparison with the polymer composite samples filled with unmodified cellulose (degradation activation energy of approximately 180 kJ/mol). To author’s best knowledge this work results in the introduction of a novel, new filler hybrid treatment approach. Moreover, valuable data regarding the properties of composites filled with cellulose fibers of various moisture contents have been provided. It should be emphasized that plant fiber-based polymer bio-materials described in this research might contribute significantly to polymer waste minimization because they are more readily degraded.

Keywords: cellulose fibers, solvent exchange, moisture content, ethylene-norbornene copolymer

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Authors: Jeounghee Kim

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Objective: To describe the incidence of complication, according to the stage of Traumatic Spinal Cord Injury (TSCI) which was treated at Asan Medical Center (AMC), Korea. Hereafter, it should be developed in nursing management protocol of traumatic SCI. Methods. Retrospectively reviewed hospital records about the patients who were admitted AMC Patients with traumatic spinal cord injury until January 2005 and December 2016 were analyzed (n=97). AMC is a single institution of 2,700 beds where patients with trauma and severe trauma can be treated. Patients who were admitted to the emergency room due to spinal cord injury and who underwent intensive care unit, general ward, and rehabilitation ward. To identify long-term complications, we excluded patients who were operated on to other hospitals after surgery. Complications such as respiratory(pneumonia, atelectasis, pulmonary embolism, and others), cardiovascular (hypotension), urinary (autonomic dysreflexia, urinary tract infection (UTI), neurogenic bladder, and others), and skin systems (pressure ulcers) from the time of admission were examined through medical records and images. Results: SCI was graded according to ASIA scale. The initial grade was checked at admission. (grade A 55(56.7%), grade B 14(14.4)%, grade C 11(11.3%), grade D 15(15.5%), and grade E 2(2.1%). The grade was rechecked when the patient was discharged after treatment. (grade A 43(44.3%), grade B 15(15.5%), grade C 12(12.4%), grade D 21(21.6%), and grade E 6(6.2%). The most common complication after SCI was UTI 24cases (mean 36.5day), sore 24cases (40.5day), and Pneumonia which was 23 cases after 10days averagely. The other complications after SCI were neuropathic pain 19 cases, surgical site infection 4 cases. 53.6% of patient who had SCI were educated about intermittent catheterization at discharge from hospital. The mean hospital stay of all SCI patients was 61days. Conclusion: The Complications after traumatic SCI were developed at various stages from acute phase to chronic phase. Nurses need to understand fully the time-course of complication in traumatic SCI to provide evidence-based practice.

Keywords: spinal cord injury, complication, nursing, rehabilitation

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Authors: Peng Zhang, Cai Liang

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The non-biodegradable plastic wastes have posed severe environmental and ecological contaminations. Numerous technologies, such as pyrolysis, incineration, and landfilling, have already been employed for the treatment of plastic waste. Compared with conventional methods, microwave has displayed unique advantages in the rapid production of hydrogen from plastic wastes. Understanding the interaction between microwave radiation and materials would promote the optimization of several parameters for the microwave reaction system. In this work, various carbon materials have been investigated to reveal microwave heating performance and the ensuing catalytic activity. Results showed that the diversity in the heating characteristic was mainly due to the dielectric properties and the individual microstructures. Furthermore, the gaps and steps among the surface of carbon materials would lead to the distortion of the electromagnetic field, which correspondingly induced plasma discharging. The intensity and location of local plasma were also studied. For high-yield H₂ production, iron nanoparticles were selected as the active sites, and a series of iron/carbon bifunctional catalysts were synthesized. Apart from the high catalytic activity, the iron particles in nano-size close to the microwave skin depth would transfer microwave irradiation to the heat, intensifying the decomposition of plastics. Under microwave radiation, iron is supported on activated carbon material with 10wt.% loading exhibited the best catalytic activity for H₂ production. Specifically, the plastics were rapidly heated up and subsequently converted into H₂ with a hydrogen efficiency of 85%. This work demonstrated a deep understanding of microwave reaction systems and provided the optimization for plastic treatment.

Keywords: plastic waste, recycling, hydrogen, microwave

Procedia PDF Downloads 52

Authors: V. Marzal, J. C. Torres, B. Garcia-Camara, Manuel Cano-Garcia, Xabier Quintana, I. Perez Garcilopez, J. M. Sanchez-Pena

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At the present time, the use of nanostructures in complex media, like liquid crystals, is widely extended to manipulate their properties, either electrical or optical. In addition, these media can also be used to control the optical properties of the nanoparticles, for instance when they are resonant. In this work, the change on electrical properties of a liquid crystal cell by adding TiO₂ nanoparticles on one of the alignment layers has been analyzed. These nanoparticles, with a diameter of 100 nm and spherical shape, were deposited in one of the substrates (ITO + polyimide) by spin-coating in order to produce a homogeneous layer. These substrates were checked using an optical microscope (objective x100) to avoid potential agglomerates. The liquid crystal cell is then fabricated, using one of these substrates and another without nanoparticles, and filled with E7. The study of the electrical response was done through impedance measurements in a long range of frequencies (3 Hz- 6 MHz) and at ambient temperature. Different nanoparticle concentrations were considered, as well as pure E7 and an empty cell for comparison purposes. Results about the effective dielectric permittivity and conductivity are presented along with models of equivalent electric circuits and its physical interpretation. As a summary, it has been observed the clear influence of the presence of the nanoparticles, strongly modifying the electric response of the device. In particular, a variation of both the effective permittivity and the conductivity of the device have been observed. This result requires a deep analysis of the effect of these nanoparticles on the trapping of free ions in the device, allowing a controlled manipulation and frequency tuning of the electrical response of these devices.

Keywords: alignment layer, electrical behavior, liquid crystal, TiO₂ nanoparticles

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Authors: David Nkurunziza, Rahman Tafahomi

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The population growth rate of the city of Kigali is increasing annually. In 1960 the population was six thousand, in 1990 it became two hundred thousand and is supposed to be 4 to 5 million incoming twenty years. With the increase in the residents living in the city of Kigali, there is also a need for an increase in social and economic infrastructures connected by the road networks to serve the residents effectively. A road network is a route that connects people to their needs and has to facilitate people to reach the social and economic facilities easily. This research analyzed the social and economic aspects of three selected roads networks passing through all three districts of the city of Kigali, whose center is the city center roundabout, thorough evaluation of the proximity of the social and economic facilities to the road network. These road networks are the city center to nyabugogo to karuruma, city center to kanogo to Rwanda to kicukiro center to Nyanza taxi park, and city center to Yamaha to kinamba to gakinjiro to kagugu health center road network. This research used a methodology of identifying and quantifying the social and economic facilities within a limited distance of 300 meters along each side of the road networks. Social facilities evaluated are the health facilities, education facilities, institution facilities, and worship facilities, while the economic facilities accessed are the commercial zones, industries, banks, and hotels. These facilities were evaluated and graded based on their distance from the road and their value. The total scores of each road network per kilometer were calculated and finally, the road networks were ranked based on their percentage score per one kilometer—this research was based on field surveys and interviews to collect data with forms and questionnaires. The analysis of the data collected declared that the road network from the city center to Yamaha to kinamba to gakinjiro to the kagugu health center is the best performer, the second is the road network from the city center to nyabugogo to karuruma, while the third is the road network from the city center to kanogo to rwandex to kicukiro center to nyaza taxi park.

Keywords: social economical aspect, road network functionality, urban road network, economic and social facilities

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Authors: Han-Qin Zheng, Yi-Fan Chiang-Hsieh, Chia-Hung Chien, Wen-Chi Chang

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As the most important non-vascular plants, algae have many research applications, including high species diversity, biofuel sources, adsorption of heavy metals and, following processing, health supplements. With the increasing availability of next-generation sequencing (NGS) data for algae genomes and transcriptomes, an integrated resource for retrieving gene expression data and metabolic pathway is essential for functional analysis and systems biology in algae. However, gene expression profiles and biological pathways are displayed separately in current resources, and making it impossible to search current databases directly to identify the cellular response mechanisms. Therefore, this work develops a novel AlgaePath database to retrieve gene expression profiles efficiently under various conditions in numerous metabolic pathways. AlgaePath, a web-based database, integrates gene information, biological pathways, and next-generation sequencing (NGS) datasets in Chlamydomonasreinhardtii and Neodesmus sp. UTEX 2219-4. Users can identify gene expression profiles and pathway information by using five query pages (i.e. Gene Search, Pathway Search, Differentially Expressed Genes (DEGs) Search, Gene Group Analysis, and Co-Expression Analysis). The gene expression data of 45 and 4 samples can be obtained directly on pathway maps in C. reinhardtii and Neodesmus sp. UTEX 2219-4, respectively. Genes that are differentially expressed between two conditions can be identified in Folds Search. Furthermore, the Gene Group Analysis of AlgaePath includes pathway enrichment analysis, and can easily compare the gene expression profiles of functionally related genes in a map. Finally, Co-Expression Analysis provides co-expressed transcripts of a target gene. The analysis results provide a valuable reference for designing further experiments and elucidating critical mechanisms from high-throughput data. More than an effective interface to clarify the transcript response mechanisms in different metabolic pathways under various conditions, AlgaePath is also a data mining system to identify critical mechanisms based on high-throughput sequencing.

Keywords: next-generation sequencing (NGS), algae, transcriptome, metabolic pathway, co-expression

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Authors: Fayad Ghawbar

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The significance of the Multiple Input Multiple Output (MIMO) system in the 5G wireless communication system is essential to enhance channel capacity and provide a high data rate resulting in a need for dual-polarization in vertical and horizontal. Furthermore, size reduction is critical in a MIMO system to deploy more antenna elements requiring a compact, low-profile design. A compact dual-band 4-MIMO antenna system has been presented in this paper with pattern and polarization diversity. The proposed single antenna structure has been designed using two antenna layers with a C shape in the front layer and a partial slot with a U-shaped cut in the ground to enhance isolation. The single antenna is printed on an FR4 dielectric substrate with an overall size of 18 mm×18 mm×1.6 mm. The 4-MIMO antenna elements were printed orthogonally on an FR4 substrate with a size dimension of 36 × 36 × 1.6 mm3 with zero edge-to-edge separation distance. The proposed compact 4-MIMO antenna elements resonate at 3.4-3.6 GHz and 4.8-5 GHz. The s-parameters measurement and simulation results agree, especially in the lower band with a slight frequency shift of the measurement results at the upper band due to fabrication imperfection. The proposed design shows isolation above -15 dB and -22 dB across the 4-MIMO elements. The MIMO diversity performance has been evaluated in terms of efficiency, ECC, DG, TARC, and CCL. The total and radiation efficiency were above 50 % across all parameters in both frequency bands. The ECC values were lower than 0.10, and the DG results were about 9.95 dB in all antenna elements. TARC results exhibited values lower than 0 dB with values lower than -25 dB in all MIMO elements at the dual-bands. Moreover, the channel capacity losses in the MIMO system were depicted using CCL with values lower than 0.4 Bits/s/Hz.

Keywords: compact antennas, MIMO antenna system, 5G communication, dual band, ECC, DG, TARC

Procedia PDF Downloads 128

Authors: Mateen A Khan, Taj Mohammad, Md. Imtaiyaz Hassan

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Alzheimer’s disease is characterized by the accumulation of the processing products of the amyloid beta peptide cleaved by amyloid precursor protein (APP). Iron increases the synthesis of amyloid beta peptides, which is why iron is present in Alzheimer's disease patients' amyloid plaques. Iron misregulation in the brain is linked to the overexpression of APP protein, which is directly related to amyloid-β aggregation in Alzheimer’s disease. The APP 5'-UTR region encodes a functional iron-responsive element (IRE) stem-loop that represents a potential target for modulating amyloid production. Targeted regulation of APP gene expression through the modulation of 5’-UTR sequence function represents a novel approach for the potential treatment of AD because altering APP translation can be used to improve both the protective brain iron balance and provide anti-amyloid efficacy. The molecular docking analysis of APP IRE RNA with eukaryotic translation initiation factors yields several models exhibiting substantial binding affinity. The finding revealed that the interaction involved a set of functionally active residues within the binding sites of eIF4F. Notably, APP IRE RNA and eIF4F interaction were stabilized by multiple hydrogen bonds with residues of APP IRE RNA and eIF4F. It was evident that APP IRE RNA exhibited a structural complementarity that tightly fit within binding pockets of eIF4F. The simulation studies further revealed the stability of the complexes formed between RNA and eIF4F, which is crucial for assessing the strength of these interactions and subsequent roles in the pathophysiology of Alzheimer’s disease. In addition, MD simulations would capture conformational changes in the IRE RNA and protein molecules during their interactions, illustrating the mechanism of interaction, conformational change, and unbinding events and how it may affect aggregation propensity and subsequent therapeutic implications. Our binding studies correlated well with the translation efficiency of APP mRNA. Overall, the outcome of this study suggests that the genomic modification and/or inhibiting the expression of amyloid protein by targeting APP IRE RNA can be a viable strategy to identify potential therapeutic targets for AD and subsequently be exploited for developing novel therapeutic approaches.

Keywords: Alzheimer's disease, Protein-RNA interaction analysis, molecular docking simulations, conformational dynamics, binding stability, binding kinetics, protein synthesis.

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Authors: Marinelle El-Khoury, Lina Bouhaya, Nivine Abbas, Hassan Sleiman

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The road network in the north of Lebanon is a prime example of the lack of pavement design and execution in Lebanon.  These roads show major distresses and hence, should be tested and evaluated. The aim of this research is to investigate and determine the deficiencies in road surface design in Lebanon, and to propose an environmentally friendly asphalt mix design. This paper consists of several parts: (i) evaluating pavement performance and structural behavior, (ii) identifying the distresses using visual examination followed by laboratory tests, (iii) deciding the optimal solution where rehabilitation or reconstruction is required and finally, (iv) identifying a sustainable method, which uses recycled material in the proposed mix. The asphalt formula contains Reclaimed Asphalt Pavement (RAP) in the base course layer and in the asphalt layer. Visual inspection of the roads in Tripoli shows that these roads face a high level of distress severity. Consequently, the pavement should be reconstructed rather than simply rehabilitated. Coring was done to determine the pavement layer thickness. The results were compared to the American Association of State Highway and Transportation Officials (AASHTO) design methodology and showed that the existing asphalt thickness is lower than the required asphalt thickness. Prior to the pavement reconstruction, the road materials were tested according to the American Society for Testing and Materials (ASTM) specification to identify whether the materials are suitable. Accordingly, the ASTM tests that were performed on the base course are Sieve analysis, Atterberg limits, modified proctor, Los Angeles, and California Bearing Ratio (CBR) tests. Results show a CBR value higher than 70%. Hence, these aggregates could be used as a base course layer. The asphalt layer was also tested and the results of the Marshall flow and stability tests meet the ASTM specifications. In the last section, an environmentally friendly mix was proposed. An optimal RAP percentage of 30%, which produced a well graded base course and asphalt mix, was determined through a series of trials.

Keywords: asphalt mix, reclaimed asphalt pavement, California bearing ratio, sustainability

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Authors: J. Prathap Kumar, G. Vaitheeswaran

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The present study investigates the role of ammonium and potassium ion in the electronic, bonding and optical properties of dinitramide salts due to their stability and non-toxic nature. A detailed analysis of bonding between NH₄ and K with dinitramide, optical transitions from the valence band to the conduction band, absorption spectra, refractive indices, reflectivity, loss function are reported. These materials are well known as oxidizers in solid rocket propellants. In the present work, we use full potential linear augmented plane wave (FP-LAPW) method which is implemented in the Wien2k package within the framework of density functional theory. The standard DFT functional local density approximation (LDA) and generalized gradient approximation (GGA) always underestimate the band gap by 30-40% due to the lack of derivative discontinuities of the exchange-correlation potential with respect to an occupation number. In order to get reliable results, one must use hybrid functional (HSE-PBE), GW calculations and Tran-Blaha modified Becke-Johnson (TB-mBJ) potential. It is very well known that hybrid functionals GW calculations are very expensive, the later methods are computationally cheap. The new developed TB-mBJ functionals use information kinetic energy density along with the charge density employed in DFT. The TB-mBJ functionals cannot be used for total energy calculations but instead yield very much improved band gap. The obtained electronic band gap at gamma point for both the ammonium dinitramide and potassium dinitramide are found to be 2.78 eV and 3.014 eV with GGA functional, respectively. After the inclusion of TB-mBJ, the band gap improved by 4.162 eV for potassium dinitramide and 4.378 eV for ammonium dinitramide. The nature of the band gap is direct in ADN and indirect in KDN. The optical constants such as dielectric constant, absorption, and refractive indices, birefringence values are presented. Overall as there are no experimental studies we present the improved band gap with TB-mBJ functional following with optical properties.

Keywords: ammonium dinitramide, potassium dinitramide, DFT, propellants

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Authors: Seyda Tugba Gunday Anil, Ayhan Bozkurt

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Next generation lithium batteries are taking more attention and single-ion polymer electrolytes are expected to play a significant role in the development of these kinds of energy storage systems. In the present work we used a different strategy to design of novel solid single-ion conducting inorganic polymer electrolytes based on lithium polyvinyl alcohol oxalate borate (Li(PVAOB), lithium polyacrylic acid oxalate borate (LiPAAOB) and poly (ethylene glycol) methacrylate (PEGMA). Free radical polymerization was used to convert PEGMA into PPEGMA and LiPAAOB is prepared from poly (acrylic acid), oxalic acid and boric acid. Blend polymer electrolytes were produced by mixing of LiPAAOB or Li (PVAOB with PPEGMA at different stoichiometric ratios to enhance the single ion conductivity of the systems. To exploit the flexible chemistry and increase the segmental mobility of the blend electrolyte, the composition was changed up to 80% with respect to the guest polymer, PPEGMA. FT-IR and differential scanning calorimeter techniques confirmed the interaction between the host and guest polymers. TGA verified that the thermal stability of the blends increased up to approximately 200 C. Scanning electron microscopy images confirm the homogeneity of the blend electrolytes. CV studies showed that electrochemical stability electrochemical stability window is approximately 5 V versus Li/Li⁺. The effect of PPEGMA on to the Lithium-ion conductivity was investigated using dielectric impedance analyzer. The maximum single ion conductivity was measured as 1.3 × 10⁻⁴ S/cm at 100 C for the sample LiPAAOB-80PPEGMA. Clearly, the results confirmed the positive effect to the increment in ionic conductivity of the blend electrolytes with the addition of PPEGMA.

Keywords: single-ion conductor, inorganic polymer, blends, polymer electrolyte

Procedia PDF Downloads 141

Authors: A. Taoufyq, B. Bakiz, A. Benlhachemi, L. Patout, D. V. Chokouadeua, F. Guinneton, G. Nolibe, A. Lyoussi, J-R. Gavarri

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Currently, the photo catalytic reactions occurring under solar illumination have attracted worldwide attentions due to a tremendous set of environmental problems. Taking the sunlight into account, it is indispensable to develop highly effective visible-light-driver photo catalysts. Nano structured materials such as MxM’1-xWO6 system are widely studied due to its interesting piezoelectric, dielectric and catalytic properties. These materials can be used in photo catalysis technique for environmental applications, such as waste water treatments. The aim of this study was to investigate the photo catalytic activity of polycrystalline phases of bismuth tungstate of formula Bi2WO6. Polycrystalline samples were elaborated using a coprecipitation technique followed by a calcination process at different temperatures (300, 400, 600 and 900°C). The obtained polycrystalline phases have been characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), and transmission electron microscopy (TEM). Crystal cell parameters and cell volume depend on elaboration temperature. High-resolution electron microscopy images and image simulations, associated with X-ray diffraction data, allowed confirming the lattices and space groups Pca21. The photo catalytic activity of the as-prepared samples was studied by irradiating aqueous solutions of Rhodamine B, associated with Bi2WO6 additives having variable crystallite sizes. The photo catalytic activity of such bismuth tungstates increased as the crystallite sizes decreased. The high specific area of the photo catalytic particles obtained at 300°C seems to condition the degradation kinetics of RhB.

Keywords: Bismuth tungstate, crystallite sizes, electron microscopy, photocatalytic activity, X-ray diffraction.

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Authors: Tingting Huang, Sha Li, Geoffrey Griffiths, Martin Lukac, Jianning Zhu

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Territorial landscapes have experienced a gradual loss of their typical characteristics during long-term human activities. In order to protect the integrity of regional landscapes, it is necessary to characterize, evaluate and protect them in a graded manner. The study takes Fujian, China, as an example and classifies the landscape characters of the site at the regional scale, middle scale, and detailed scale. A multi-scale approach combining parametric and holistic approaches is used to classify and partition the landscape character types (LCTs) and landscape character areas (LCAs) at different scales, and a multi-element landscape assessment approach is adopted to explore the conservation strategies of the landscape character. Firstly, multiple fields and multiple elements of geography, nature and humanities were selected as the basis of assessment according to the scales. Secondly, the study takes a parametric approach to the classification and partitioning of landscape character, Principal Component Analysis, and two-stage cluster analysis (K-means and GMM) in MATLAB software to obtain LCTs, combines with Canny Operator Edge Detection Algorithm to obtain landscape character contours and corrects LCTs and LCAs by field survey and manual identification methods. Finally, the study adopts the Landscape Sensitivity Assessment method to perform landscape character conservation analysis and formulates five strategies for different LCAs: conservation, enhancement, restoration, creation, and combination. This multi-scale identification approach can efficiently integrate multiple types of landscape character elements, reduce the difficulty of broad-scale operations in the process of landscape character conservation, and provide a basis for landscape character conservation strategies. Based on the natural background and the restoration of regional characteristics, the results of landscape character assessment are scientific and objective and can provide a strong reference in regional and national scale territorial spatial planning.

Keywords: parameterization, multi-scale, landscape character identify, landscape character assessment

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Authors: Mustafa Gulsen, Mitat Koz

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The aim of this study is to investigate the effect of lumbar stabilisation and proprioceptive neuromuscular facilitation (PNF) training on muscle strength and muscle endurance. The participants were 64 between the ages of 15-69 (53.04 ± 14.59), who were graded protrusion and bulging lumbar herniation according to 'Macnab Classification'. The participants were divided into four groups as each group had 16 participants: lumbar stabilitation training, PNF training, physical therapy and control groups. Sociodemographic features were recorded. Then their muscle strength tests (by isokinetic dynamometer (Cybex 770 Norm Lumex Inc, Ronkonkoma, NY, USA) were recorded. Before and after applications; visual analogue scale (VAS), Oswestry Disability İndex were applied by a physical therapist. The participants in lumbar stabilisation group performed 45 minutes, 5 days in a week for 4 weeks strength training with a physical therapist observation. The participants in PNF group performed 5 days in a week for 4 weeks with pelvic patterns of PNF by a physiotherapist. The participants in physical therapy group underwent Hotpack, Tens and Ultrasound therapy 5 days in a week for 4 weeks. The participants in control group didn’t take any training programme. After 4 weeks, the evaluations were repeated. There were significant increases in muscle strength and muscle endurance in lumbar stabilization training group. Also in pain intensity at rest and during activity in this group and in Oswestry disability index of patients, there were significant improvements (p < 0.05). In PNF training group likewise, there were significant improvements in muscle strength, muscle endurance, pain intensity at rest and with activity and in Oswestry disability index (p < 0.05). But improvements in the Lumbar Stabilization group was better than PNF Group. We found significant differences only in pain intensity at rest and with activity and in Oswestry disability index (p < 0.05). in the patients in Physical Therapy group. We think that appropriate physiotherapy and rehabilitation program which will be prepared for patients, to protect the waist circumference of patients with low muscle strength and low muscle endurance will increase muscle strength and muscle endurance. And it is expected that will reduce pain and will provide advances toward correcting functional disability of the patients.

Keywords: disc herniation, endurance, lumbar stabilitation exercises, PNF, strength

Procedia PDF Downloads 261

Authors: Naima Guenifi, Shiromani Balmukund Rahi, Amina Bechka

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Tunnel FET is one of the most suitable alternatives FET devices for conventional CMOS technology for low-power electronics and applications. Due to its lower subthreshold swing (SS) value, it is a strong follower of low power applications. It is a quantum FET device that follows the band to band (B2B) tunneling transport phenomena of charge carriers. Due to band to band tunneling, tunnel FET is suffering from a lower switching current than conventional metal-oxide-semiconductor field-effect transistor (MOSFET). For improvement of device features and limitations, the newly invented negative capacitance concept of ferroelectric material is implemented in conventional Tunnel FET structure popularly known as NC TFET. The present research work has implemented the idea of high-k gate dielectric added with ferroelectric material on double gate Tunnel FET for implementation of negative capacitance. It has been observed that the idea of negative capacitance further improves device features like SS value. It helps to reduce power dissipation and switching energy. An extensive investigation for circularity uses for digital, analog/RF and linearity features of double gate NCTFET have been adopted here for research work. Several essential designs paraments for analog/RF and linearity parameters like transconductance(gm), transconductance generation factor (gm/IDS), its high-order derivatives (gm2, gm3), cut-off frequency (fT), gain-bandwidth product (GBW), transconductance generation factor (gm/IDS) has been investigated for low power RF applications. The VIP₂, VIP₃, IMD₃, IIP₃, distortion characteristics (HD2, HD3), 1-dB, the compression point, delay and power delay product performance have also been thoroughly studied.

Keywords: analog/digital, ferroelectric, linearity, negative capacitance, Tunnel FET, transconductance

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Authors: Randall E. Osborne

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A four-step ‘humanities’ thought model has been used in an interdisciplinary course for almost two decades and has been proven to aid in student abilities to become more inclusive in their world view. Lack of tolerance for ambiguity can interfere with this progression so we developed an assignment that seems to have assisted students in developing more tolerance for ambiguity and, therefore, opened them up to make more progress on the critical thought model. A four-step critical thought model (built from a humanities education approach) is used in an interdisciplinary course on prejudice, discrimination, and hate in an effort to minimize egocentrism and promote sociocentrism in college students. A fundamental barrier to this progression is a lack of tolerance for ambiguity. The approach to the course is built on the assumption that Tolerance for Ambiguity (characterized by a dislike of uncertain, ambiguous or situations in which expected behaviors are uncertain, will like serve as a barrier (if tolerance is low) or facilitator (if tolerance is high) of active ‘engagement’ with assignments. Given that active engagement with course assignments would be necessary to promote an increase in critical thought and the degree of multicultural attitude change, tolerance for ambiguity inhibits critical thinking and, ultimately multicultural attitude change. As expected, those students showing the least amount of decrease (or even an increase) in intolerance across the semester, earned lower grades in the course than those students who showed a significant decrease in intolerance, t(1,19) = 4.659, p < .001. Students who demonstrated the most change in their Tolerance for Ambiguity (showed an increasing ability to tolerate ambiguity) earned the highest grades in the course. This is, especially, significant because faculty did not know student scores on this measure until after all assignments had been graded and course grades assigned. An assignment designed to assist students in making their assumption and inferences processes visible so they could be explored, was implemented with the goal of this exploration then promoting more tolerance for ambiguity, which, as already outlined, promotes critical thought. The assignment offers students two options and then requires them to explore what they have learned about inferences and/or assumptions This presentation outlines the assignment and demonstrates the humanities model, what students learn from particular assignments and how it fosters a change in Tolerance for Ambiguity which, serves as the foundational component of critical thinking.

Keywords: critical thinking, humanities education, sociocentrism, tolerance for ambiguity

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Authors: Faizan Ali, Dayu Zhou, Xiaohua Liu, Tony Schenk, Johannes Muller, Uwe Schroeder

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Recently, the ferroelectricity (FE) and anti-ferroelectricity (AFE) introduced in so-called 'high-k dielectric' HfO₂ material incorporated with various dopants (Si, Gd, Y, Sr, Gd, Al, and La, etc.), HfO₂-ZrO₂ solid-solution, Al or Si-doped Hf₀.₅Zr₀.₅O₂ and even undoped HfO₂ thin films. The origin of FE property was attributed to the formation of a non-centrosymmetric orthorhombic (o) phase of space group Pbc2₁. To the author’s best knowledge, AFE property was observed only in HfO₂ doped with a certain amount of Si, Al, HfₓZr₁₋ₓO₂ (0 ≤ x < 0.5), and in Si or Al-doped Hf₀.₅Zr₀.₅O₂. The origin of the anti-ferroelectric behavior is an electric field induced phase transition between the non-polar tetragonal (t) and the polar ferroelectric orthorhombic (o) phase. Compared with the significant amount of studies for the FE properties in the context of non-volatile memories, AFE properties of HfO₂-based and HfₓZr₁₋ₓO₂ (HZO) thin films have just received attention recently for energy-related applications such as electrocaloric cooling, pyroelectric energy harvesting, and electrostatic energy storage. In this work, energy storage and solid state cooling properties of Si-doped HfO₂ AFE thin films are investigated. Owing to the high field-induced polarization and slim double hysteresis, an extremely large Energy storage density (ESD) value of 61.2 J cm⁻³ is achieved at 4.5 MV cm⁻¹ with high efficiency of ~65%. In addition, the ESD and efficiency exhibit robust thermal stability in 210-400 K temperature range and excellent endurance up to 10⁹ times of charge/discharge cycling at a very high electric field of 4.0 MV cm⁻¹. Similarly, for solid-state cooling, the maximum adiabatic temperature change (

Keywords: thin films, energy storage, endurance, solid state cooling, anti-ferroelectric

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Authors: O. J. Osunkeye, P. O. Fakolade, B. E. Olorede

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Broilers productions depend on the provision of adequate and goo quality feed containing all the nutrients, including proteins, carbohydrate, fats, vitamins, minerals and water. All these nutrients have to be provided at a required amount to support maximum productivity and normal physiological functions and demands. Among these nutrients proteins are particularly important, since they are essential for meat and muscle production, optimum growth and health status. Poultry production industry in the developing countries is been threatened because of the over dependency on Soybean meal as one of the key/major conventional protein stuff for feeding livestock. Even the competition between man and livestock for Soybean and other protein sources made the price of this feed stuff to be on the increase. Hence the needs to seek for an alternative feed stuff which is cheap and less competitive. This study showed the blood profile, organ and carcass characteristics and performance of broilers fed with Cowpea Testa Meal (CTM) based diets. Four diets were formulated with Cowpea Testa replacing Soybean at 0%, 15%, 30%, and 50% graded levels. One hundred and twenty day-old unsexed broiler birds were allotted to these four treatments with 3 replicates of 10 birds per replicate. The results showed no significant differences in all the haematological parameters measured (P>0.05), the serum metabolites analysis revealed significant different in Cholesterol (99.8 mg/dl, 112.84 mg/dl, 131.07 mg/dl and 97.66 mg/dl respectively) (P<0.05) among others. There were significant differences within the diets for average daily weight gain, average feed intake and feed to gain ratio. The birds on control (0%) and CTM gained more weight than those fed with 30% and 50% CTM diets. The organs and carcass primal cuts of the broilers expressed significant different for the spleen (0.12 g, 0.09 g, 0.11 g and 0.14 g respectively), lungs (0.97 g, 0.72 g, 0.77 g and 1.01g respectively) and proventriculus (0.96 g, 0.99 g, 0.81 g and 0.85 g respectively) (P<0.05). For the carcass, there were no significant differences (P<0.05) in the breast, thigh, drumstick, wing and neck except for the Back (21.27 g, 21.04 g, 17.71 g, and 17.89 g respectively). In conclusion, CTM inclusion in broiler’s diet could be used as an alternative feed stuff in replacement of Soybean meal up to 15% without any adverse effects as revealed by the blood profile and to increase the growth performance of the birds.

Keywords: physiological functions, cholesterol, blood profiles, CTM and carcass analysis

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