Search results for: left ventricular function
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 6118

Search results for: left ventricular function

1558 Investigation of the Use of Surface-Modified Waste Orange Pulp for the Adsorption of Remazol Black B

Authors: Ceren Karaman, Onur Karaman

Abstract:

The adsorption of Remazol Black B (RBB), an anionic dye, onto dried orange pulp (DOP) adsorbent prepared by only drying and by treating with cetyltrimetylammonium bromide (CTAB), a cationic surfactant, surface-modified orange pulp (SMOP) was studied in a stirred batch experiments system at 25°C. The adsorption of RBB on each adsorbent as a function of surfactant dosage, initial pH of the solution and initial dye concentration was investigated. The optimum amount of CTAB was found to be 25g/l. For RBB adsorption studies, while working pH value for the DOP adsorbent system was determined as 2.0, it was observed that this value shifted to 8.0 when the 25 g/l CTAB treated-orange pulp (SMOP) adsorbent was used. It was obtained that the adsorption rate and capacity increased to a certain value, and the adsorption efficiency decreased with increasing initial RBB concentration for both DOP and SMOP adsorbents at pH 2.0 and pH 8.0. While the highest adsorption capacity for DOP was determined as 62.4 mg/g at pH 2.0, and as 325.0 mg/g for SMOP at pH 8.0. As a result, it can be said that permanent cationic coating of the adsorbent surface by CTAB surfactant shifted the working pH from 2.0 to 8.0 and it increased the dye adsorption rate and capacity of orange pulp much more significantly at pH 8.0. The equilibrium RBB adsorption data on each adsorbent were best described by the Langmuir isotherm model. The adsorption kinetics of RBB on each adsorbent followed a pseudo-second-order model. Moreover, the intraparticle diffusion model was used to describe the kinetic data. It was found that diffusion is not the only rate controlling step. The adsorbent was characterized by the Brunauer–Emmett–Teller (BET) analysis, Fourier-transform-infrared (FTIR) spectroscopy, and scanning-electron-microscopy (SEM). The mechanism for the adsorption of RBB on the SMOP may include hydrophobic interaction, van der Waals interaction, stacking and electrostatic interaction.

Keywords: adsorption, Cetyltrimethylammonium Bromide (CTAB), orange pulp, Remazol Black B (RBB), surface modification

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1557 Cultural Disposition and Implicit Dehumanization of Sexualized Females by Women

Authors: Hong Im Shin

Abstract:

Previous research demonstrated that self-objectification (women view themselves as objects for use) is related to system-justification. Three studies investigated whether cultural disposition as its system-justifying function could have an impact on self-objectification and dehumanization of sexualized women and men. Study 1 (N = 91) employed a survey methodology to examine the relationship between cultural disposition (collectivism vs. individualism), trait of system-justification, and self-objectification. The results showed that the higher tendency of collectivism was related to stronger system-justification and self-objectification. Study 2 (N = 60 females) introduced a single category implicit association task (SC-IAT) to assess the extent to which sexually objectified women were associated with uniquely human attributes (i.e., culture) compared to animal-related attributes (i.e., nature). According to results, female participants associated sexually objectified female targets less with human attributes compared to animal-related attributes. Study 3 (N = 46) investigated whether priming to individualism or collectivism was associated to system justification and sexual objectification of men and women with the use of a recognition task involving upright and inverted pictures of sexualized women and men. The results indicated that the female participants primed to individualism showed an inversion effect for sexualized women and men (person-like recognition), whereas there was no inversion effect for sexualized women in the priming condition of collectivism (object-like recognition). This implies that cultural disposition plays a mediating role for rationalizing the gender status, implicit dehumanization of sexualized females and self-objectification. Future research directions are discussed.

Keywords: cultural disposition, dehumanization, implicit test, self-objectification

Procedia PDF Downloads 238
1556 Effectiveness of Myofascial Release Technique in Treatment of Sacroiliac Joint Hypo-Mobility in Postnatal Women

Authors: Ahmed A. Abd El Rahim, Mohamed M. M. Essa, Magdy M. A. Shabana, Said A. Mohamed, Mohamed Ibrahim Mabrouk

Abstract:

Background: Sacroiliac joint (SIJ) dysfunction is considered the main cause of pregnancy-related back pain, which may continue to persist postnatally. Myofascial release technique (MFR) is an application of low-intensity, prolonged stretch to myofascial structures to improve function by increasing the sliding properties of restricted myofascial tissues. Purpose: This study was designed to investigate the effect of MFR on postnatal SIJ hypo-mobility. Materials and Methods: Fifty postnatal women complaining of SIJ hypo-mobility participated in this study. Their ages ranged from 26 to 35 yrs., and their body mass index (BMI) didn`t exceed 30 kg/m2. They were randomly assigned to two equal groups, group A (Gr. A) and group B (Gr. B). Both groups received three sessions per week for eight successive weeks. Gr. A received a traditional physical therapy program, while Gr. B received a traditional physical therapy program in addition to MFR. Doppler imaging of vibration was utilized to measure SIJ mobility pre- and post-intervention, and an electronic digital goniometer was used to measure back flexion and extension Range of motion. Results: Findings revealed a statistical improvement in post-intervention values of SIJ mobility in addition to trunk flexion and extension ROM in Gr. B compared to Gr. A (P<0.001). Conclusion: Adding MFR to traditional physical therapy programs is highly recommended in the treatment of SIJ hypo-mobility in postnatal women.

Keywords: sacroiliac hypo-mobility, sacroiliac dysfunction, myofascial release technique, traditional physical therapy, postnatal

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1555 Geometry, the language of Manifestation of Tabriz School’s Mystical Thoughts in Architecture (Case Study: Dome of Soltanieh)

Authors: Lida Balilan, Dariush Sattarzadeh, Rana Koorepaz

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In the Ilkhanid era, the mystical school of Tabriz manifested itself as an art school in various aspects, including miniatures, architecture, urban planning and design, simultaneously with the expansion of the many sciences of its time. In this era, mysticism, both in form and in poetry and prose, as well as in works of art reached its peak. Mysticism, as an inner belief and thought, brought the audience to the artistic and aesthetical view using allegorical and symbolic expression of the religion and had a direct impact on the formation of the intellectual and cultural layers of the society. At the same time, Mystic school of Tabriz could create a symbolic and allegorical language to create magnificent works of architecture with the expansion of science in various fields and using various sciences such as mathematics, geometry, science of numbers and by Abjad letters. In this era, geometry is the middle link between mysticism and architecture and it is divided into two categories, including intellectual and sensory geometry and based on its function. Soltaniyeh dome is one of the prominent buildings of the Tabriz school with the shrine land use. In this article, information is collected using a historical-interpretive method and the results are analyzed using an analytical-comparative method. The results of the study suggest that the designers and builders of the Soltaniyeh dome have used shapes, colors, numbers, letters and words in the form of motifs, geometric patterns as well as lines and writings in levels and layers ranging from plans to decorations and arrays for architectural symbolization and encryption to express and transmit mystical ideas.

Keywords: geometry, Tabriz school, mystical thoughts, dome of Soltaniyeh

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1554 On the Effect of Carbon on the Efficiency of Titanium as a Hydrogen Storage Material

Authors: Ghazi R. Reda Mahmoud Reda

Abstract:

Among the metal that forms hydride´s, Mg and Ti are known as the most lightweight materials; however, they are covered with a passive layer of oxides and hydroxides and require activation treatment under high temperature ( > 300 C ) and hydrogen pressure ( > 3 MPa) before being used for storage and transport applications. It is well known that small graphite addition to Ti or Mg, lead to a dramatic change in the kinetics of mechanically induced hydrogen sorption ( uptake) and significantly stimulate the Ti-Hydrogen interaction. Many explanations were given by different authors to explain the effect of graphite addition on the performance of Ti as material for hydrogen storage. Not only graphite but also the addition of a polycyclic aromatic compound will also improve the hydrogen absorption kinetics. It will be shown that the function of carbon addition is two-fold. First carbon acts as a vacuum cleaner, which scavenges out all the interstitial oxygen that can poison or slow down hydrogen absorption. It is also important to note that oxygen favors the chemisorption of hydrogen, which is not desirable for hydrogen storage. Second, during scavenging of the interstitial oxygen, the carbon reacts with oxygen in the nano and microchannel through a highly exothermic reaction to produce carbon dioxide and monoxide which provide the necessary heat for activation and thus in the presence of carbon lower heat of activation for hydrogen absorption which is observed experimentally. Furthermore, the product of the reaction of hydrogen with the carbon oxide will produce water which due to ball milling hydrolyze to produce the linear H5O2 + this will reconstruct the primary structure of the nanocarbon to form secondary structure, where the primary structure (a sheet of carbon) are connected through hydrogen bonding. It is the space between these sheets where physisorption or defect mediated sorption occurs.

Keywords: metal forming hydrides, polar molecule impurities, titanium, phase diagram, hydrogen absorption

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1553 Epigenomic Analysis of Lgr5+ Stem Cells in Gastrointestinal Tract

Authors: Hyo-Min Kim, Seokjin Ham, Mi-Joung Yoo, Minseon Kim, Tae-Young Roh

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The gastrointestinal (GI) tract of most animals, including murine, is highly compartmentalized epithelia which also provide distinct different functions of its own tissue. Nevertheless, these epithelia share certain characteristics that enhance immune responses to infections and maintain the barrier function of the intestine. GI tract epithelia also undergo regeneration not only in homeostatic conditions but also in a response to the damage. A full turnover of the murine gastrointestinal epithelium occurs every 4-5 day, a process that is regulated and maintained by a minor population of Lgr5+ adult stem cell that commonly conserved in the bottom of crypts through GI tract. Maintenance of the stem cell is somehow regulated by epigenetic factors according to recent studies. Chromatin vacancy, remodelers, histone variants and histone modifiers could affect adult stem cell fate. In this study, Lgr5-EGFP reporter mouse was used to take advantage of exploring the epigenetic dynamics among Lgr5 positive mutual stem cell in GI tract. Cells were isolated by fluorescence-activated cell sorting (FACS), gene expression levels, chromatin accessibility changes and histone modifications were analyzed. Some notable chromatin structural related epigenetic variants were detected. To identify the overall cell-cell interaction inside the stem cell niche, an extensive genome-wide analysis should be also followed. According to the results, nevertheless, we expected a broader understanding of cellular niche maintaining stem cells and epigenetic barriers through conserved stem cell in GI tract. We expect that our study could provide more evidence of adult stem cell plasticity and more chances to understand each stem cell that takes parts in certain organs.

Keywords: adult stem cell, epigenetics, LGR5 stem cell, gastrointestinal tract

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1552 The Localization and Function of p38α Mitogen-Activated Protein Kinase (MAPK) in Rat Oocytes

Authors: Shifu Hu, Qiong Yu, Wei Xia, Changhong Zhu

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Background: P38α MAPK, which is a member of the canonical MAPK family, is activated in response to various extracellular stresses and plays a role in multiple cellular processes. It is well known that p38α MAPK play vital roles in oocyte maturation, but the localization and functional roles of p38α MAPK during the meiotic maturation of rat oocytes remain unknown. Study Design: In this study, western-blot and immunofluorescent staining were used to investigate the expression and subcellular localization of p38α MAPK during the meiotic maturation of rat oocytes. SB203580, a specific inhibitor of p38α MAPK, was used to study the roles of p38α MAPK in the meiotic cell cycle of rat oocytes. Results: The results found that p38α MAPK phosphorylation (p-p38α MAPK, indicative of p38α MAPK activation) was low at the germinal vesicle (GV) stage, increased 3 h after germinal vesicle breakdown (GVBD), and maintained its maximum at MI (metaphase I) or M II (metaphase II). The p-p38α MAPK mainly accumulated in the germinal vesicle and had no obvious expression in the nucleus. From GVBD to M II, p-p38α MAPK was distributed in the cytoplasm around either the chromosomes or the spindle. We used SB203580, an inhibitor of p38α MAPK, to investigate the possible functional role of p38α MAPK during rat oocyte meiotic maturation. Treatment of GV stage oocytes with 20 μM SB203580 blocked p-p38α MAPK activity, and the spindles appeared abnormal. Additionally, the rate of GVBD after 3h of culture with 20 μM SB203580 (58.8%) was significantly inhibited compared with the control (82.5%, p < 0.05), and the polar body extrusion rate after 12 h of culture with SB203580 was also significantly decreased compared with the control (40.1 vs. 73.3%, p < 0.05). Conclusions: These data indicate that p38α MAPK may play a vital role in rat oocyte meiotic maturation.

Keywords: meiotic maturation, oocyte, p38α MAPK, spindle

Procedia PDF Downloads 159
1551 Integrated Two Stage Processing of Biomass Conversion to Hydroxymethylfurfural Esters Using Ionic Liquid as Green Solvent and Catalyst: Synthesis of Mono Esters

Authors: Komal Kumar, Sreedevi Upadhyayula

Abstract:

In this study, a two-stage process was established for the synthesis of HMF esters using ionic liquid acid catalyst. Ionic liquid catalyst with different strength of the Bronsted acidity was prepared in the laboratory and characterized using 1H NMR, FT-IR, and 13C NMR spectroscopy. Solid acid catalyst from the ionic liquid catalyst was prepared using the immobilization method. The acidity of the synthesized acid catalyst was measured using Hammett function and titration method. Catalytic performance was evaluated for the biomass conversion to 5-hydroxymethylfurfural (5-HMF) and levulinic acid (LA) in methyl isobutyl ketone (MIBK)-water biphasic system. A good yield of 5-HMF and LA was found at the different composition of MIBK: Water. In the case of MIBK: Water ratio 10:1, good yield of 5-HMF was observed at ambient temperature 150˚C. Upgrading of 5-HMF into monoesters from the reaction of 5-HMF and reactants using biomass-derived monoacid were performed. Ionic liquid catalyst with -SO₃H functional group was found to be best efficient in comparative of a solid acid catalyst for the esterification reaction and biomass conversion. A good yield of 5-HMF esters with high 5-HMF conversion was found to be at 105˚C using the best active catalyst. In this process, process A was the hydrothermal conversion of cellulose and monomer into 5-HMF and LA using acid catalyst. And the process B was the esterification followed by using similar acid catalyst. All monoesters of 5-HMF synthesized here can be used in chemical, cross linker for adhesive or coatings and pharmaceutical industry. A theoretical density functional theory (DFT) study for the optimization of the ionic liquid structure was performed using the Gaussian 09 program to find out the minimum energy configuration of ionic liquid catalyst.

Keywords: biomass conversion, 5-HMF, Ionic liquid, HMF ester

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1550 Parameter Optimization and Thermal Simulation in Laser Joining of Coach Peel Panels of Dissimilar Materials

Authors: Masoud Mohammadpour, Blair Carlson, Radovan Kovacevic

Abstract:

The quality of laser welded-brazed (LWB) joints were strongly dependent on the main process parameters, therefore the effect of laser power (3.2–4 kW), welding speed (60–80 mm/s) and wire feed rate (70–90 mm/s) on mechanical strength and surface roughness were investigated in this study. The comprehensive optimization process by means of response surface methodology (RSM) and desirability function was used for multi-criteria optimization. The experiments were planned based on Box– Behnken design implementing linear and quadratic polynomial equations for predicting the desired output properties. Finally, validation experiments were conducted on an optimized process condition which exhibited good agreement between the predicted and experimental results. AlSi3Mn1 was selected as the filler material for joining aluminum alloy 6022 and hot-dip galvanized steel in coach peel configuration. The high scanning speed could control the thickness of IMC as thin as 5 µm. The thermal simulations of joining process were conducted by the Finite Element Method (FEM), and results were validated through experimental data. The Fe/Al interfacial thermal history evidenced that the duration of critical temperature range (700–900 °C) in this high scanning speed process was less than 1 s. This short interaction time leads to the formation of reaction-control IMC layer instead of diffusion-control mechanisms.

Keywords: laser welding-brazing, finite element, response surface methodology (RSM), multi-response optimization, cross-beam laser

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1549 Enhancement in Bactericidal Activity of Hydantoin Based Microsphere from Smooth to Rough

Authors: Rajani Kant Rai, Jayakrishnan Athipet

Abstract:

There have been several attempts to prepare polymers with antimicrobial properties by doping with various N-halamines. Hydantoins (Cyclic N-halamine) is of importance due to their stability rechargeable chloroamide function, broad-spectrum anti-microbial action and ability to prevent resistance to the organisms. Polymerizable hydantoins are synthesized by tethering vinyl moieties to 5,5,-dialkyl hydantoin sacrificing the imide hydrogen in the molecule thereby restricting the halogen capture only to the amide nitrogen that results in compromised antibacterial activity. In order to increase the activity of the antimicrobial polymer, we have developed a scheme to maximize the attachment of chlorine to the amide and the imide moieties of hydantoin. Vinyl hydantoin monomer, (Z)-5-(4-((3-methylbuta-1,3-dien-2-yl)oxy)benzylidene)imidazolidine-2,4-dione (MBBID) was synthesized and copolymerized with a commercially available monomer, methyl methacrylate, by free radical polymerization. The antimicrobial activity of hydantoin is strongly dependent on their surface area and hence their microbial activity increases when incorporated in microspheres or nanoparticles as compared to their bulk counterpart. In this regard, smooth and rough surface microsphere of the vinyl monomer (MBBID) with commercial monomer was synthesized. The oxidative chlorine content of the copolymer ranged from 1.5 to 2.45 %. Further, to demonstrate the water purification potential, the thin column was packed with smooth or rough microspheres and challenged with simulated contaminated water that exhibited 6 log kill (total kill) of the bacteria in 20 minutes of exposure with smooth (25 mg/ml) and rough microsphere (15.0 mg/ml).

Keywords: cyclic N-halamine, vinyl hydantoin monomer, rough surface microsphere, simulated contaminated water

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1548 Blood Thicker Than Water: A Case Report on Familial Ovarian Cancer

Authors: Joanna Marie A. Paulino-Morente, Vaneza Valentina L. Penolio, Grace Sabado

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Ovarian cancer is extremely hard to diagnose in its early stages, and those afflicted at the time of diagnosis are typically asymptomatic and in the late stages of the disease, with metastasis to other organs. Ovarian cancers often occur sporadically, with only 5% associated with hereditary mutations. Mutations in the BRCA1 and BRCA2 tumor suppressor genes have been found to be responsible for the majority of hereditary ovarian cancers. One type of ovarian tumor is Malignant Mixed Mullerian Tumor (MMMT), which is a very rare and aggressive type, accounting for only 1% of all ovarian cancers. Reported is a case of a 43-year-old G3P3 (3003), who came into our institution due to a 2-month history of difficulty of breathing. Family history reveals that her eldest and younger sisters both died of ovarian malignancy, with her younger sister having a histopathology report of endometrioid ovarian carcinoma, left ovary stage IIIb. She still has 2 asymptomatic sisters. Physical examination pointed to pleural effusion of right lung, and presence of bilateral ovarian new growth, which had a Sassone score of 13. Admitting Diagnosis was G3P3 (3003), Ovarian New Growth, bilateral, Malignant; Pleural effusion secondary to malignancy. BRCA was requested to establish a hereditary mutation; however, the patient had no funds. Once the patient was stabilized, TAHBSO with surgical staging was performed. Intraoperatively, the pelvic cavity was occupied by firm, irregularly shaped ovaries, with a colorectal metastasis. Microscopic sections from both ovaries and the colorectal metastasis had pleomorphic tumor cells lined by cuboidal to columnar epithelium exhibiting glandular complexity, displaying nuclear atypia and increased nuclear-cytoplasmic ratio, which are infiltrating the stroma, consistent with the features of Malignant Mixed Mullerian Tumor, since MMMT is composed histologically of malignant epithelial and sarcomatous elements. In conclusion, discussed is the clinic-pathological feature of a patient with primary ovarian Malignant Mixed Mullerian Tumor, a rare malignancy comprising only 1% of all ovarian neoplasms. Also, by understanding the hereditary ovarian cancer syndromes and its relation to this patient, it cannot be overemphasized that a comprehensive family history is really fundamental for early diagnosis. The familial association of the disease, given that the patient has two sisters who were diagnosed with an advanced stage of ovarian cancer and succumbed to the disease at a much earlier age than what is reported in the general population, points to a possible hereditary syndrome which occurs in only 5% of ovarian neoplasms. In a low-resource setting, being in a third world country, the following will be recommended for monitoring and/or screening women who are at high risk for developing ovarian cancer, such as the remaining sisters of the patient: 1) Physical examination focusing on the breast, abdomen, and rectal area every 6 months. 2) Transvaginal sonography every 6 months. 3) Mammography annually. 4) CA125 for postmenopausal women. 5) Genetic testing for BRCA1 and BRCA2 will be reserved for those who are financially capable.

Keywords: BRCA, hereditary breast-ovarian cancer syndrome, malignant mixed mullerian tumor, ovarian cancer

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1547 Architecture for QoS Based Service Selection Using Local Approach

Authors: Gopinath Ganapathy, Chellammal Surianarayanan

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Services are growing rapidly and generally they are aggregated into a composite service to accomplish complex business processes. There may be several services that offer the same required function of a particular task in a composite service. Hence a choice has to be made for selecting suitable services from alternative functionally similar services. Quality of Service (QoS)plays as a discriminating factor in selecting which component services should be selected to satisfy the quality requirements of a user during service composition. There are two categories of approaches for QoS based service selection, namely global and local approaches. Global approaches are known to be Non-Polynomial (NP) hard in time and offer poor scalability in large scale composition. As an alternative to global methods, local selection methods which reduce the search space by breaking up the large/complex problem of selecting services for the workflow into independent sub problems of selecting services for individual tasks are coming up. In this paper, distributed architecture for selecting services based on QoS using local selection is presented with an overview of local selection methodology. The architecture describes the core components, namely, selection manager and QoS manager needed to implement the local approach and their functions. Selection manager consists of two components namely constraint decomposer which decomposes the given global or workflow level constraints in local or task level constraints and service selector which selects appropriate service for each task with maximum utility, satisfying the corresponding local constraints. QoS manager manages the QoS information at two levels namely, service class level and individual service level. The architecture serves as an implementation model for local selection.

Keywords: architecture of service selection, local method for service selection, QoS based service selection, approaches for QoS based service selection

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1546 Evidence Theory Based Emergency Multi-Attribute Group Decision-Making: Application in Facility Location Problem

Authors: Bidzina Matsaberidze

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It is known that, in emergency situations, multi-attribute group decision-making (MAGDM) models are characterized by insufficient objective data and a lack of time to respond to the task. Evidence theory is an effective tool for describing such incomplete information in decision-making models when the expert and his knowledge are involved in the estimations of the MAGDM parameters. We consider an emergency decision-making model, where expert assessments on humanitarian aid from distribution centers (HADC) are represented in q-rung ortho-pair fuzzy numbers, and the data structure is described within the data body theory. Based on focal probability construction and experts’ evaluations, an objective function-distribution centers’ selection ranking index is constructed. Our approach for solving the constructed bicriteria partitioning problem consists of two phases. In the first phase, based on the covering’s matrix, we generate a matrix, the columns of which allow us to find all possible partitionings of the HADCs with the service centers. Some constraints are also taken into consideration while generating the matrix. In the second phase, based on the matrix and using our exact algorithm, we find the partitionings -allocations of the HADCs to the centers- which correspond to the Pareto-optimal solutions. For an illustration of the obtained results, a numerical example is given for the facility location-selection problem.

Keywords: emergency MAGDM, q-rung orthopair fuzzy sets, evidence theory, HADC, facility location problem, multi-objective combinatorial optimization problem, Pareto-optimal solutions

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1545 Classical and Bayesian Inference of the Generalized Log-Logistic Distribution with Applications to Survival Data

Authors: Abdisalam Hassan Muse, Samuel Mwalili, Oscar Ngesa

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A generalized log-logistic distribution with variable shapes of the hazard rate was introduced and studied, extending the log-logistic distribution by adding an extra parameter to the classical distribution, leading to greater flexibility in analysing and modeling various data types. The proposed distribution has a large number of well-known lifetime special sub-models such as; Weibull, log-logistic, exponential, and Burr XII distributions. Its basic mathematical and statistical properties were derived. The method of maximum likelihood was adopted for estimating the unknown parameters of the proposed distribution, and a Monte Carlo simulation study is carried out to assess the behavior of the estimators. The importance of this distribution is that its tendency to model both monotone (increasing and decreasing) and non-monotone (unimodal and bathtub shape) or reversed “bathtub” shape hazard rate functions which are quite common in survival and reliability data analysis. Furthermore, the flexibility and usefulness of the proposed distribution are illustrated in a real-life data set and compared to its sub-models; Weibull, log-logistic, and BurrXII distributions and other parametric survival distributions with 3-parmaeters; like the exponentiated Weibull distribution, the 3-parameter lognormal distribution, the 3- parameter gamma distribution, the 3-parameter Weibull distribution, and the 3-parameter log-logistic (also known as shifted log-logistic) distribution. The proposed distribution provided a better fit than all of the competitive distributions based on the goodness-of-fit tests, the log-likelihood, and information criterion values. Finally, Bayesian analysis and performance of Gibbs sampling for the data set are also carried out.

Keywords: hazard rate function, log-logistic distribution, maximum likelihood estimation, generalized log-logistic distribution, survival data, Monte Carlo simulation

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1544 Influence of CA, SR and BA Substitution on lafeo3Performances During Chemical Looping Processes

Authors: Rong Sun, Laihong Shen

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La-based perovskite oxygen carriers, especially the doped-La(M)FeO₃, showed excellent performances during chemical looping processes. However, the mechanisms of the undoped and doped La(M)FeO₃ are not clear at present, making the mechanisms clear may help the development of chemical looping technologies. In this paper, the method based on the density function theory (DFT) was used to analysis the influence of Ca, Sr, and Ba doping of La on the electronic structure, while the CO oxidation mechanisms on the surface of LaFeO₃ and Ca-doped LaFeO₃ oxygen carriers were also analyzed. The results showed that the band gap was decreased by the doping of low valence. While the doping of low valence element Ca, Sr, and Ba at La site simultaneously resulted to the moving of the valence band toward high energy and made the valence band cross the Fermi energy level. This was resulted from the holes generated by divalent ion substitution. The holes can change the total magnetization from antiferromagnet to weakly ferromagnetism. The calculation results about the formation of oxygen vacancy showed that substitutions of Ca, Sr, and Ba caused a large drop in oxygen vacancy formation energy, indicating that the bulk oxygen transport was improved. Based on the optimized bulk of the undoped and Ca-doped LaFeO₃(010) surface, the CO adsorption was analyzed. The results indicated that the adsorption energy increased by divalent ion substitution, meaning that the adsorption stability decreased. The results can provide a certain theoretical basis for the development of perovskite oxides in chemical looping technologies.

Keywords: chemical looping technologies, lanthanum ferrate (LaFeO₃), divalent ion substitution, CO oxidation

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1543 Unsupervised Echocardiogram View Detection via Autoencoder-Based Representation Learning

Authors: Andrea Treviño Gavito, Diego Klabjan, Sanjiv J. Shah

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Echocardiograms serve as pivotal resources for clinicians in diagnosing cardiac conditions, offering non-invasive insights into a heart’s structure and function. When echocardiographic studies are conducted, no standardized labeling of the acquired views is performed. Employing machine learning algorithms for automated echocardiogram view detection has emerged as a promising solution to enhance efficiency in echocardiogram use for diagnosis. However, existing approaches predominantly rely on supervised learning, necessitating labor-intensive expert labeling. In this paper, we introduce a fully unsupervised echocardiographic view detection framework that leverages convolutional autoencoders to obtain lower dimensional representations and the K-means algorithm for clustering them into view-related groups. Our approach focuses on discriminative patches from echocardiographic frames. Additionally, we propose a trainable inverse average layer to optimize decoding of average operations. By integrating both public and proprietary datasets, we obtain a marked improvement in model performance when compared to utilizing a proprietary dataset alone. Our experiments show boosts of 15.5% in accuracy and 9.0% in the F-1 score for frame-based clustering, and 25.9% in accuracy and 19.8% in the F-1 score for view-based clustering. Our research highlights the potential of unsupervised learning methodologies and the utilization of open-sourced data in addressing the complexities of echocardiogram interpretation, paving the way for more accurate and efficient cardiac diagnoses.

Keywords: artificial intelligence, echocardiographic view detection, echocardiography, machine learning, self-supervised representation learning, unsupervised learning

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1542 A Review of Kinematics and Joint Load Forces in Total Knee Replacements Influencing Surgical Outcomes

Authors: Samira K. Al-Nasser, Siamak Noroozi, Roya Haratian, Adrian Harvey

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A total knee replacement (TKR) is a surgical procedure necessary when there is severe pain and/or loss of function in the knee. Surgeons balance the load in the knee and the surrounding soft tissue by feeling the tension at different ranges of motion. This method can be unreliable and lead to early failure of the joint. The ideal kinematics and load distribution have been debated significantly based on previous biomechanical studies surrounding both TKRs and normal knees. Intraoperative sensors like VERASENSE and eLibra have provided a method for the quantification of the load indicating a balanced knee. A review of the literature written about intraoperative sensors and tension/stability of the knee was done. Studies currently debate the quantification of the load in medial and lateral compartments specifically. However, most research reported that following a TKR the medial compartment was loaded more heavily than the lateral compartment. In several cases, these results were shown to increase the success of the surgery because they mimic the normal kinematics of the knee. In conclusion, most research agrees that an intercompartmental load differential of between 10 and 20 pounds, where the medial load was higher than the lateral, and an absolute load of less than 70 pounds was ideal. However, further intraoperative sensor development could help improve the accuracy and understanding of the load distribution on the surgical outcomes in a TKR. A reduction in early revision surgeries for TKRs would provide an improved quality of life for patients and reduce the economic burden placed on both the National Health Service (NHS) and the patient.

Keywords: intraoperative sensors, joint load forces, kinematics, load balancing, and total knee replacement

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1541 Women Academics' Insecure Identity at Work: A Millennials Phenomenon

Authors: Emmanouil Papavasileiou, Nikos Bozionelos, Liza Howe-Walsh, Sarah Turnbull

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Purpose: The research focuses on women academics’ insecure identity at work and examines its link with generational identity. The aim is to enrich understanding of identities at work as a crucial attribute of managing academics in the context of the proliferation of managerialist controls of audit, accountability, monitoring, and performativity. Methodology: Positivist quantitative methodology was utilized. Data were collected from the Scientific Women's Academic Network (SWAN) Charter. Responses from 155 women academics based in the British Higher Education system were analysed. Findings: Analysis showed high prevalence of strong imposter feelings among participants, suggesting high insecurity at work among women academics in the United Kingdom. Generational identity was related to imposter feelings. In particular, Millennials scored significantly higher than the other generational groups. Research implications: The study shows that imposter feelings are variously manifested among the prevalent generations of women academics, while generational identity is a significant antecedent of such feelings. Research limitations: Caution should be exercised in generalizing the findings to national cultural contexts beyond the United Kingdom. Practical and social implications: Contrary to popular depictions of Millennials as self-centered, narcissistic, materialistic and demanding, women academics who are members of this generational group appear significantly more insecure than the preceding generations. Value: The study provides insightful understandings into women academics’ identity at work as a function of generational identity, and provides a fruitful avenue for further research within and beyond this gender group and profession.

Keywords: academics, generational diversity, imposter feelings, United Kingdom, women, work identity

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1540 A Multi-Dimensional Neural Network Using the Fisher Transform to Predict the Price Evolution for Algorithmic Trading in Financial Markets

Authors: Cristian Pauna

Abstract:

Trading the financial markets is a widespread activity today. A large number of investors, companies, public of private funds are buying and selling every day in order to make profit. Algorithmic trading is the prevalent method to make the trade decisions after the electronic trading release. The orders are sent almost instantly by computers using mathematical models. This paper will present a price prediction methodology based on a multi-dimensional neural network. Using the Fisher transform, the neural network will be instructed for a low-latency auto-adaptive process in order to predict the price evolution for the next period of time. The model is designed especially for algorithmic trading and uses the real-time price series. It was found that the characteristics of the Fisher function applied at the nodes scale level can generate reliable trading signals using the neural network methodology. After real time tests it was found that this method can be applied in any timeframe to trade the financial markets. The paper will also include the steps to implement the presented methodology into an automated trading system. Real trading results will be displayed and analyzed in order to qualify the model. As conclusion, the compared results will reveal that the neural network methodology applied together with the Fisher transform at the nodes level can generate a good price prediction and can build reliable trading signals for algorithmic trading.

Keywords: algorithmic trading, automated trading systems, financial markets, high-frequency trading, neural network

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1539 The Use of the Mediated Learning Experience in Response of Special Needs Education

Authors: Maria Luisa Boninelli

Abstract:

This study wants to explore the effects of a mediated intervention program in a primary school. The participants where 120 students aged 8-9, half of them Italian and half immigrants of first or second generation. The activities consisted on the cognitive enhancement of the participants through Feuerstein’s Instrumental Enrichment, (IE) and on an activity centred on body awareness and mediated learning experience. Given that there are limited studied on learners in remedial schools, the current study intented to hypothesized that participants exposed to mediation would yiel a significant improvement in cognitive functioning. Hypothesis One proposed that, following the intervention, improved Q1vata scores of the participants would occur in each of the groups. Hypothesis two postulated that participants within the Mediated Learning Experience would perform significantly better than those group of control. For the intervention a group of 60 participants constituted a group of Mediation sample and were exposed to Mediated Learning Experience through Enrichment Programm. Similiary the other 60 were control group. Both the groups have students with special needs and were exposed to the same learning goals. A pre-experimental research design, in particular a one-group pretest-posttest approach was adopted. All the participants in this study underwent pretest and post test phases whereby they completed measures according to the standard instructions. During the pretest phase, all the participants were simultaneously exposed to Q1vata test for logical and linguistic evaluation skill. During the mediation intervention, significant improvement was demonstrated with the group of mediation. This supports Feuerstein's Theory that initial poor performance was a result of a lack of mediated learning experience rather than inherent difference or deficiencies. Furthermore the use of an appropriate mediated learning enabled the participants to function adequately.

Keywords: cognitive structural modifiability, learning to learn, mediated learning experience, Reuven Feuerstein, special needs

Procedia PDF Downloads 378
1538 Communicative Competence in French Language for Nigerian Teacher-Trainees in the New-Normal Society Using Mobile Apps as a Lifelong Learning Tool

Authors: Olukemi E. Adetuyi-Olu-Francis

Abstract:

Learning is natural for living. One stops learning when life ends. Hence, there is no negotiating life-long learning. An individual has the innate ability to learn as many languages as he/she desires as long as life exists. French language education to every Nigerian teacher-trainee is a necessity. Nigeria’s geographical location requires that the French language should be upheld for economic and cultural co-operations between Nigeria and the francophone countries sharing borders with her. The French language will enhance the leadership roles of the teacher-trainees and their ability to function across borders. The 21st century learning tools are basically digital, and many apps are complementing the actual classroom interactions. This study examined the communicative competence in the French language to equip Nigerian teacher-trainees in the new-normal society using mobile apps as a lifelong learning tool. Three research questions and hypotheses guided the study, and the researcher adopted a pre-test, a post-test experimental design, using a sample size of 87 teacher-trainees in South-south geopolitical zone of Nigeria. Results showed that the use of mobile apps is effective for learning the French language. One of the recommendations is that the use of mobile apps should be encouraged for all Nigerian youths to learn the French language for enhancing leadership roles in the world of work and for international interactions for socio-economic co-operations with Nigerian neighboring countries.

Keywords: communicative competence, french language, life long learning, mobile apps, new normal society, teacher trainees

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1537 Time-Dependent Reliability Analysis of Corrosion Affected Cast Iron Pipes with Mixed Mode Fracture

Authors: Chun-Qing Li, Guoyang Fu, Wei Yang

Abstract:

A significant portion of current water networks is made of cast iron pipes. Due to aging and deterioration with corrosion being the most predominant mechanism, the failure rate of cast iron pipes is very high. Although considerable research has been carried out in the past few decades, most are on the effect of corrosion on the structural capacity of pipes using strength theory as the failure criterion. This paper presents a reliability-based methodology for the assessment of corrosion affected cast iron pipe cracking failures. A nonlinear limit state function taking into account all three fracture modes is proposed for brittle metal pipes with mixed mode fracture. A stochastic model of the load effect is developed, and time-dependent reliability method is employed to quantify the probability of failure and predict the remaining service life. A case study is carried out using the proposed methodology, followed by sensitivity analysis to investigate the effects of the random variables on the probability of failure. It has been found that the larger the inclination angle or the Mode I fracture toughness is, the smaller the probability of pipe failure is. It has also been found that the multiplying and exponential coefficients k and n in the power law corrosion model and the internal pressure have the most influence on the probability of failure for cast iron pipes. The methodology presented in this paper can assist pipe engineers and asset managers in developing a risk-informed and cost-effective strategy for better management of corrosion-affected pipelines.

Keywords: corrosion, inclined surface cracks, pressurized cast iron pipes, stress intensity

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1536 Revenue Management of Perishable Products Considering Freshness and Price Sensitive Customers

Authors: Onur Kaya, Halit Bayer

Abstract:

Global grocery and supermarket sales are among the largest markets in the world and perishable products such as fresh produce, dairy and meat constitute the biggest section of these markets. Due to their deterioration over time, the demand for these products depends highly on their freshness. They become totally obsolete after a certain amount of time causing a high amount of wastage and decreases in grocery profits. In addition, customers are asking for higher product variety in perishable product categories, leading to less predictable demand per product and to more out-dating. Effective management of these perishable products is an important issue since it is observed that billions of dollars’ worth of food is expired and wasted every month. We consider coordinated inventory and pricing decisions for perishable products with a time and price dependent random demand function. We use stochastic dynamic programming to model this system for both periodically-reviewed and continuously-reviewed inventory systems and prove certain structural characteristics of the optimal solution. We prove that the optimal ordering decision scenario has a monotone structure and the optimal price value decreases by time. However, the optimal price changes in a non-monotonic structure with respect to inventory size. We also analyze the effect of 1 different parameters on the optimal solution through numerical experiments. In addition, we analyze simple-to-implement heuristics, investigate their effectiveness and extract managerial insights. This study gives valuable insights about the management of perishable products in order to decrease wastage and increase profits.

Keywords: age-dependent demand, dynamic programming, perishable inventory, pricing

Procedia PDF Downloads 247
1535 Influences on the Evolution of Le Corbusier's Early Work

Authors: Parima Kotanut

Abstract:

It is commonly known that Le Corbusier, a pivotal figure in modern architecture, developed a diverse range of architectural languages. Due to his emblematic work of the International Style has become a central focus in architectural education and historiography, many scholars have redirected their attention to the architect's formative years and early career. One of the significant contributions to this is the treatise titled Le Corbusier before Le Corbusier: Applied Arts, Architecture, Painting, Photography, 1907-1922, published in conjunction with an exhibition in Switzerland in 2002, aiming to provide an extensive catalog of Le Corbusier's personal life, the societal contexts he engaged with, and his artistic pursuits. While the publication offers profound insights into the experiences and ideologies that shaped his early works, it only partially addresses the influence of those formative ideas on his later practice. This raises a question regarding the long-term impact of his early experiences as Charles-Edouard Jeanneret upon his later practice as Le Corbusier. The research aims to re-examine theoretical frameworks proposed by Le Corbusier and other scholars in juxtaposition to his built works, correspondences, and artistic persona. Although there are several milestones shaping Le Corbusier's works, through historical research, the paper is divided into three categories: 1911 "Voyage d'Orient", the immersion in the technology of reinforced concrete, and the participation in the Parisian art world. These three experiences serve as a foundation for his lifetime theories concerning function, construction, and form of architecture, demonstrating how experiences beyond the architectural domain are critical to the design of buildings. Furthermore, this study intends to illuminate the contributions of lesser-known figures who consistently influenced Le Corbusier's passionate journey toward his architectural identity.

Keywords: architecture, Le Corbusier, 20th century architecture, modern architecture

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1534 The Use of Polar Substituent Groups for Promoting Azo Disperse Dye Solubility and Reactivity for More Economic and Environmental Benign Applications: A Computational Study

Authors: Olaide O. Wahab, Lukman O. Olasunkanmi, Krishna K. Govender, Penny P. Govender

Abstract:

The economic and environmental challenges associated with azo disperse dyes applications are due to poor aqueous solubility and low degradation tendency which stems from low chemical reactivity. Poor aqueous solubility property of this group of dyes necessitates the use of dispersing agents which increase operational costs and also release toxic chemical components into the environment, while their low degradation tendency is due to the high stability of the azo functional group (-N=N-) in their chemical structures. To address these problems, this study investigated theoretically the effects of some polar substituents on the aqueous solubility and reactivity properties of disperse yellow (DY) 119 dye with a view to theoretically develop new azo disperse dyes with improved solubility in water and higher degradation tendency in the environment using DMol³ computational code. All calculations were carried out using the Becke and Perdew version of Volsko-Wilk-Nusair (VWN-BP) level of density functional theory in conjunction with double numerical basis set containing polarization function (DNP). The aqueous solubility determination was achieved with conductor-like screening model for realistic solvation (COSMO-RS) in conjunction with known empirical solubility model, while the reactivity was predicted using frontier molecular orbital calculations. Most of the new derivatives studied showed evidence of higher aqueous solubility and degradation tendency compared to the parent dye. We conclude that these derivatives are promising alternative dyes for more economic and environmental benign dyeing practice and therefore recommend them for synthesis.

Keywords: aqueous solubility, azo disperse dye, degradation, disperse yellow 119, DMol³, reactivity

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1533 Permeability Prediction Based on Hydraulic Flow Unit Identification and Artificial Neural Networks

Authors: Emad A. Mohammed

Abstract:

The concept of hydraulic flow units (HFU) has been used for decades in the petroleum industry to improve the prediction of permeability. This concept is strongly related to the flow zone indicator (FZI) which is a function of the reservoir rock quality index (RQI). Both indices are based on reservoir porosity and permeability of core samples. It is assumed that core samples with similar FZI values belong to the same HFU. Thus, after dividing the porosity-permeability data based on the HFU, transformations can be done in order to estimate the permeability from the porosity. The conventional practice is to use the power law transformation using conventional HFU where percentage of error is considerably high. In this paper, neural network technique is employed as a soft computing transformation method to predict permeability instead of power law method to avoid higher percentage of error. This technique is based on HFU identification where Amaefule et al. (1993) method is utilized. In this regard, Kozeny and Carman (K–C) model, and modified K–C model by Hasan and Hossain (2011) are employed. A comparison is made between the two transformation techniques for the two porosity-permeability models. Results show that the modified K-C model helps in getting better results with lower percentage of error in predicting permeability. The results also show that the use of artificial intelligence techniques give more accurate prediction than power law method. This study was conducted on a heterogeneous complex carbonate reservoir in Oman. Data were collected from seven wells to obtain the permeability correlations for the whole field. The findings of this study will help in getting better estimation of permeability of a complex reservoir.

Keywords: permeability, hydraulic flow units, artificial intelligence, correlation

Procedia PDF Downloads 136
1532 Quantifying Impairments in Whiplash-Associated Disorders and Association with Patient-Reported Outcomes

Authors: Harpa Ragnarsdóttir, Magnús Kjartan Gíslason, Kristín Briem, Guðný Lilja Oddsdóttir

Abstract:

Introduction: Whiplash-Associated Disorder (WAD) is a health problem characterized by motor, neurological and psychosocial symptoms, stressing the need for a multimodal treatment approach. To achieve individualized multimodal approach, prognostic factors need to be identified early using validated patient-reported and objective outcome measures. The aim of this study is to demonstrate the degree of association between patient-reported and clinical outcome measures of WAD patients in the subacute phase. Methods: Individuals (n=41) with subacute (≥1, ≤3 months) WAD (I-II), medium to high-risk symptoms, or neck pain rating ≥ 4/10 on the Visual Analog Scale (VAS) were examined. Outcome measures included measurements for movement control (Butterfly test) and cervical active range of motion (cAROM) using the NeckSmart system, a computer system using an inertial measurement unit (IMU) that connects to a computer. The IMU sensor is placed on the participant’s head, who receives visual feedback about the movement of the head. Patient-reported neck disability, pain intensity, general health, self-perceived handicap, central sensitization, and difficulties due to dizziness were measured using questionnaires. Excel and R statistical software were used for statistical analyses. Results: Forty-one participants, 15 males (37%), 26 females (63%), mean (SD) age 36.8 (±12.7), underwent data collection. Mean amplitude accuracy (AA) (SD) in the Butterfly test for easy, medium, and difficult paths were 2.4mm (0.9), 4.4mm (1.8), and 6.8mm (2.7), respectively. Mean cAROM (SD) for flexion, extension, left-, and right rotation were 46.3° (18.5), 48.8° (17.8), 58.2° (14.3), and 58.9° (15.0), respectively. Mean scores on the Neck Disability Index (NDI), VAS, Dizziness Handicap Inventory (DHI), Central Sensitization Inventory (CSI), and 36-Item Short Form Survey RAND version (RAND) were 43% (17.4), 7 (1.7), 37 (25.4), 51 (17.5), and 39.2 (17.7) respectively. Females showed significantly greater deviation for AA compared to males for easy and medium Butterfly paths (p<0.05). Statistically significant moderate to strong positive correlation was found between the DHI and easy (r=0.6, p=0.05), medium (r=0.5, p=0.05)) and difficult (r=0.5, p<0.05) Butterfly paths, between the total RAND score and all cAROMs (r between 0.4-0.7, p≤0.05) except flexion (r=0.4, p=0.7), and between the NDI score and CSI (r=0.7, p<0.01), VAS (r=0.5, p<0.01), and DHI (r=0.7, p<0.01) scores respectively. Discussion: All patient-reported and objective measures were found to be outside the reference range. Results suggest females have worse movement control in the neck in the subacute WAD phase. However, no statistical difference based on gender was found in patient-reported measures. Suggesting females might have worse movement control than males in general in this phase. The correlation found between DHI and the Butterfly test can be explained because the DHI measures proprioceptive symptoms like dizziness and eye movement disorders that can affect the outcome of movement control tests. A correlation was found between the total RAND score and cAROM, suggesting that a reduced range of motion affects the quality of life. Significance: The NeckSmart system can detect abnormalities in cAROM, fine movement control, and kinesthesia of the neck. Results suggest females have worse movement control than males. Results show a moderate to a high correlation between several patient-reported and objective measurements.

Keywords: whiplash associated disorders, car-collision, neck, trauma, subacute

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1531 Teenagers in Conflict with Law: Exploratory Study about Psychic Suffering

Authors: Carolina Alcântara, Ileno Costa

Abstract:

This study had the objective to systemize the main psycho-social and socioeducational aspects that related with the psychic suffering of adolescents in conflict of law and freedom privation. This research wanted to verify the signals and symptoms identified trough themselves perceptions related to their condition of health/insanity. In a similar way, it was objectified to know the opinions of the ambient conditions of the institution the use of the currently available resources for Health Service and Educational Service. The methodological proposal is based on the quant-qualitative analysis of interviews half-structuralized carried through with 36 teenagers was using psychiatric medication continuously. The data had pointed the experiences of sleeplessness and nightmares, associates or not with experiences of loss of reality (hallucinations) had constituted the illness most frequent. The self-punishment behavior appeared at second place. With regard to the ambient factors, it was verified that institution had, in general way, guaranteed the physical integrity and the maintenance of the health. Amongst the current available resources of Health Service, the administration of anticonvulsivants, in association with other psychotropic drugs has been widely used. The school was viewed as important device of available in the institution. By means of the adolescent’s understanding who do not like to go to the school, they don’t disqualify the knowledge, in contrast, they wanted for knowledge, however, they were frustrated for not having their educational supplies adequately, affirming that the school is weak or they do not learn. Finally, among the possible conclusions guided for the Winnicott’s thought, it was observed that institution in analysis is a representative of the paternal function. However, to begin the self-cure process is necessary that formation of therapeutical bonds. The group of teachers is identified as the main tool of change.

Keywords: serious psychic suffering, adolescent in conflict with the law, delinquency, privation of freedom

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1530 Optimal Continuous Scheduled Time for a Cumulative Damage System with Age-Dependent Imperfect Maintenance

Authors: Chin-Chih Chang

Abstract:

Many manufacturing systems suffer failures due to complex degradation processes and various environment conditions such as random shocks. Consider an operating system is subject to random shocks and works at random times for successive jobs. When successive jobs often result in production losses and performance deterioration, it would be better to do maintenance or replacement at a planned time. A preventive replacement (PR) policy is presented to replace the system before a failure occurs at a continuous time T. In such a policy, the failure characteristics of the system are designed as follows. Each job would cause a random amount of additive damage to the system, and the system fails when the cumulative damage has exceeded a failure threshold. Suppose that the deteriorating system suffers one of the two types of shocks with age-dependent probabilities: type-I (minor) shock is rectified by a minimal repair, or type-II (catastrophic) shock causes the system to fail. A corrective replacement (CR) is performed immediately when the system fails. In summary, a generalized maintenance model to scheduling replacement plan for an operating system is presented below. PR is carried out at time T, whereas CR is carried out when any type-II shock occurs and the total damage exceeded a failure level. The main objective is to determine the optimal continuous schedule time of preventive replacement through minimizing the mean cost rate function. The existence and uniqueness of optimal replacement policy are derived analytically. It can be seen that the present model is a generalization of the previous models, and the policy with preventive replacement outperforms the one without preventive replacement.

Keywords: preventive replacement, working time, cumulative damage model, minimal repair, imperfect maintenance, optimization

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1529 Human-Computer Interaction: Strategies for Ensuring the Design of User-Centered Web Interfaces for Smartphones

Authors: Byron Joseph A. Hallar, Annjeannette Alain D. Galang, Maria Visitacion N. Gumabay

Abstract:

The widespread adoption and increasing proliferation of smartphones that started during the first decade of the twenty-first century have enabled their users to communicate and access information in ways that were merely thought of as possibilities in the few years before the smartphone revolution. A product of the convergence of the cellular phone and portable computer, the smartphone provides an additional important function that used to be the exclusive domain of desktop-bound computers and portable computers: Web Browsing. For increasing numbers of users, the smartphone and allied devices such as tablet computers have become their first and often their only means of accessing the World Wide Web. This has led to the development of websites that cater to the needs of the new breed of smartphone-carrying web users. The smaller size of smartphones as compared with conventional computers has provided unique challenges to web interface designers. The smaller screen size and touchscreen interface have made it much more difficult to read and navigate through web pages that were in most part designed for traditional desktop and portable computers. Although increasing numbers of websites now provide an alternate website formatted for smartphones, problems with ease of use, reliability and usability still remain. This study focuses on the identification of the problems associated with smartphone web interfaces, the compliance with accepted standards of user-oriented web interface design, the strategies that could be utilized to ensure the design of user-centric web interfaces for smartphones, and the identification of the current trends and developments related to user-centric web interface design intended for the consumption of smartphone users.

Keywords: human-computer interaction, user-centered design, web interface, mobile, smartphone

Procedia PDF Downloads 356