Search results for: double negative metamaterial
Commenced in January 2007
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Edition: International
Paper Count: 5716

Search results for: double negative metamaterial

5266 Long Standing Orbital Floor Fracture Repair: Case Report

Authors: Hisham A. Hashem, Sameh Galal, Bassem M. Moeshed

Abstract:

A 36 years old male patient presented to our unit with a history of motor-car accident from 7 months complaining of disfigurement and double vision. On examination and investigations, there was an orbital floor fracture in the left eye with inferior rectus muscle entrapment causing diplopia, dystopia and enophthalmos. Under general anesthesia, a sub-ciliary incision was performed, and the orbital floor fracture was repaired with a double layer Medpor sheet (30x50x15) with removing and freeing fibrosis that was present and freeing of the inferior rectus muscle. Remarkable improvement of the dystopia was noticed, however, there was a residual diplopia in upgaze and enophthalmos. He was then referred to a strabismologist, which upon examination found left hypotropia of 8 ΔD corrected by 8 ΔD base up prism and positive forced duction test on elevation and pseudoptosis. Under local anesthesia, a limbal incision approach with hangback 4mm recession of inferior rectus muscle was performed after identifying an inferior rectus muscle structure. Improvement was noted shortly postoperative with correction of both diplopia and pseudoptosis. Follow up after 1, 4 and 8 months was done showing a stable condition. Delayed surgery in cases of orbital floor fracture may still hold good results provided proper assessment of the case with management of each sign separately.

Keywords: diplopia, dystopia, late surgery, orbital floor fracture

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5265 Pinch Technology for Minimization of Water Consumption at a Refinery

Authors: W. Mughees, M. Alahmad

Abstract:

Water is the most significant entity that controls local and global development. For the Gulf region, especially Saudi Arabia, with its limited potable water resources, the potential of the fresh water problem is highly considerable. In this research, the study involves the design and analysis of pinch-based water/wastewater networks. Multiple water/wastewater networks were developed using pinch analysis involving direct recycle/material recycle method. Property-integration technique was adopted to carry out direct recycle method. Particularly, a petroleum refinery was considered as a case study. In direct recycle methodology, minimum water discharge and minimum fresh water resource targets were estimated. Re-design (or retrofitting) of water allocation in the networks was undertaken. Chemical Oxygen Demand (COD) and hardness properties were taken as pollutants. This research was based on single and double contaminant approach for COD and hardness and the amount of fresh water was reduced from 340.0 m3/h to 149.0 m3/h (43.8%), 208.0 m3/h (61.18%) respectively. While regarding double contaminant approach, reduction in fresh water demand was 132.0 m3/h (38.8%). The required analysis was also carried out using mathematical programming technique. Operating software such as LINGO was used for these studies which have verified the graphical method results in a valuable and accurate way. Among the multiple water networks, the one possible water allocation network was developed based on mass exchange.

Keywords: minimization, water pinch, water management, pollution prevention

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5264 Impact of Welding Distortion on the Design of Fabricated T-Girders Using Finite Element Modeling

Authors: Ahmed Hammad, Yehia Abdel-Nasser, Mohamed Shamma

Abstract:

The main configuration of ship construction consists of standard and fabricated stiffening members which are commonly used in shipbuilding such as fabricated T-sections. During the welding process, the non-uniform heating and rapid cooling lead to the inevitable presence of out-of-plane distortion and welding induced residual stresses. Because of these imperfections, the fabricated structural members may not attain their design load to be carried. The removal of these imperfections will require extra man-hours. In the present work, controlling these imperfections has been investigated at both design and fabrication stages. A typical fabricated T-girder is selected to investigate the problem of these imperfections using double-side welding. A numerical simulation based on finite element (FE) modeling has been used to investigate the effect of different parameters of the selected fabricated T-girder such as geometrical properties and welding sequences on the magnitude of welding imperfections. FE results were compared with the results of experimental model of a double-side fillet weld. The present work concludes that: Firstly, in the design stage, the optimum geometry of the fabricated T- girder is determined based on minimum steel weight and out- of- plane distortion. Secondly, in the fabrication stage, the best welding sequence is determined on the basis of minimum welding out- of- plane distortion.

Keywords: fabricated T-girder, FEM, out-of-plane distortion, section modulus, welding residual stresses

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5263 Coping with the Stress and Negative Emotions of Care-Giving by Using Techniques from Seneca, Epictetus, and Marcus Aurelius

Authors: Arsalan Memon

Abstract:

There are many challenges that a caregiver faces in average everyday life. One such challenge is coping with the stress and negative emotions of caregiving. The Stoics (i.e. Lucius Annaeus Seneca [4 B.C.E. - 65 C.E.], Epictetus [50-135 C.E.], and Marcus Aurelius [121-180 C.E.]) have provided coping techniques that are useful for dealing with stress and negative emotions. This paper lists and explains some of the fundamental coping techniques provided by the Stoics. For instance, some Stoic coping techniques thus follow (the list is far from exhaustive): a) mindfulness: to the best of your ability, constantly being aware of your thoughts, habits, desires, norms, memories, likes/dislikes, beliefs, values, and of everything outside of you in the world (b) constantly adjusting one’s expectations in accordance with reality, c) memento mori: constantly reminding oneself that death is inevitable and that death is not to be seen as evil, and d) praemeditatio malorum: constantly detaching oneself from everything that is so dear to one so that the least amount of suffering follows from the loss, damage, or ceasing to be of such entities. All coping techniques will be extracted from the following original texts by the Stoics: Seneca’s Letters to Lucilius, Epictetus’ Discourses and the Encheiridion, and Marcus Aurelius’ Meditations. One major finding is that the usefulness of each Stoic coping technique can be empirically tested by anyone in the sense of applying it one’s own life especially when one is facing real-life challenges. Another major finding is that all of the Stoic coping techniques are predicated upon, and follow from, one fundamental principle: constantly differentiate what is and what is not in one’s control. After differentiating it, one should constantly habituate oneself in not controlling things that are beyond one’s control. For example, the following things are beyond one’s control (all things being equal): death, certain illnesses, being born in a particular socio-economic family, etc. The conclusion is that if one habituates oneself by practicing to the best of one’s ability both the fundamental Stoic principle and the Stoic coping techniques, then such a habitual practice can eventually decrease the stress and negative emotions that one experiences by being a caregiver.

Keywords: care-giving, coping techniques, negative emotions, stoicism, stress

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5262 Activity of Commonly Used Intravenous Nutrient and Bisolvon in Neonatal Intensive Care Units against Biofilm Cells and Their Synergetic Effect with Antibiotics

Authors: Marwa Fady Abozed, Hemat Abd El Latif, Fathy Serry, Lotfi El Sayed

Abstract:

The purpose of this study was to investigate the efficacy of intravenous nutrient(soluvit, vitalipid, aminoven infant, lipovenos) and bisolvon commonly used in neonatal intensive care units against biofilm cells of staphylococcus aureus, Staphylococcus epidermidis, Pseudomonas aerguinosa and klebseilla pneumonia as they are the most commonly isolated organisms and are biofilm producers. Also, the synergetic acticity of soluvit, heparin, bisolvon with antibiotics and its effect on minimum biofilm eradication concentration(MBEC) was tested. Intravenous nutrient and bromohexine are widely used in newborns. Numbers of viable cell count released from biofilm after treatment with intravenous nutrient and bromohexine were counted to compare the efficacy. The percentage of reduction in biofilm regrowth in case of using soluvit was 43-51% and 36-42 % for Gram positive and Gram negative respectively, on adding the vitalipid the percentage was 45-50 %and 37-41% for Gram positive and Gram negative respectively. While, in case of using bisolvon the percentage was 46-52% and 47-48% for Gram positive and Gram negative respectively. Adding lipovenos had a reduction percentage of 48-52% and 48-49% for Gram positive and Gram negative respectively. While, adding aminoven infant the percentage was 10-15% and 9-11% for Gram positive and Gram negative respectively. Adding soluvit, heparin and bisolvon to antibiotics had synergic effect. soluvit with ciprofloxacin has 8-16 times decrease than minimum biofilm eradication concentration (MBEC) for ciprofloxacin alone. While, by adding soluvit to vancomycin the MBEC reduced by 16 times than MBEC of vancomycin alone. In case of combination soluvit with cefotaxime, amikacin and gentamycin the reduction in MBEC was 16, 8 and 6-32 times respectively. The synergetic effect of adding heparin to ciprofloxacin, vancomycin, cefotaxime, amikacin and gentamicin was 2 times reduction with all except in case of gram negative the range of reduction was 0-2 with both gentamycin and ciprofloxacin. Bisolvon exihited synergetic effect with ciprofloxacin, vancomycin, cefotaxime, amikacin and gentamicin by 16, 32, 32, 8, 32-64 and 32 times decrease in MBEC respectively.

Keywords: biofilm, neonatal intensive care units, antibiofilm agents, intravenous nutrient

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5261 CeO₂-Decorated Graphene-coated Nickel Foam with NiCo Layered Double Hydroxide for Efficient Hydrogen Evolution Reaction

Authors: Renzhi Qi, Zhaoping Zhong

Abstract:

Under the dual pressure of the global energy crisis and environmental pollution, avoiding the consumption of non-renewable fossil fuels based on carbon as the energy carrier and developing and utilizing non-carbon energy carriers are the basic requirements for the future new energy economy. Electrocatalyst for water splitting plays an important role in building sustainable and environmentally friendly energy conversion. The oxygen evolution reaction (OER) is essentially limited by the slow kinetics of multi-step proton-electron transfer, which limits the efficiency and cost of water splitting. In this work, CeO₂@NiCo-NRGO/NF hybrid materials were prepared using nickel foam (NF) and nitrogen-doped reduced graphene oxide (NRGO) as conductive substrates by multi-step hydrothermal method and were used as highly efficient catalysts for OER. The well-connected nanosheet array forms a three-dimensional (3D) network on the substrate, providing a large electrochemical surface area with abundant catalytic active sites. The doping of CeO₂ in NiCo-NRGO/NF electrocatalysts promotes the dispersion of substances and its synergistic effect in promoting the activation of reactants, which is crucial for improving its catalytic performance against OER. The results indicate that CeO₂@NiCo-NRGO/NF only requires a lower overpotential of 250 mV to drive the current density of 10 mA cm-2 for an OER reaction of 1 M KOH, and exhibits excellent stability at this current density for more than 10 hours. The double layer capacitance (Cdl) values show that CeO₂@NiCo-NRGO/NF significantly affects the interfacial conductivity and electrochemically active surface area. The hybrid structure could promote the catalytic performance of oxygen evolution reaction, such as low initial potential, high electrical activity, and excellent long-term durability. The strategy for improving the catalytic activity of NiCo-LDH can be used to develop a variety of other electrocatalysts for water splitting.

Keywords: CeO₂, reduced graphene oxide, NiCo-layered double hydroxide, oxygen evolution reaction

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5260 Effect of Risperidone and Haloperidol on Clinical Picture and Some Biochemical Parameters of Schizophrenic Libyan Patients

Authors: Mabruka S. Elashheb, Adullah Ali Bakush

Abstract:

Schizophrenia is referred to as a disorder, not a disease, because there has not been any clear, reliable, and specific etiological factor. Even if schizophrenia is not a very frequent disease, it is among the most burdensome and costly illnesses worldwide. Prevention of relapse is a major goal of maintenance treatment in patients with psychotic disorders. We performed a comparison of a newer, atypical antipsychotic drug, Risperidone, and an older, conventional neuroleptic drug, Haloperidol, in terms of the effect on the usual kidney and liver functions and negative and positive symptoms in patients with schizophrenia and schizoaffective disorder after three and five weeks of their treatments. It is apparent from the comparative data of Haloperidol and Risperidone treatments in schizophrenic patients that Resperidone had superior improvement of negative and positive symptoms of patients, no harmful effect on liver and kidney functions and greater efficacy and faster recovery from schizophrenic symptoms in patients. On the basis of our findings of the present study, we concluded that treatment with Risperidone is superior to Haloperidol in reducing the risk of relapse among outpatients with schizophrenic disorders.

Keywords: schizophrenia, Haloperidol, Risperidone, positive and negative symptom

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5259 Diversification of Indonesian Terasi Shrimp (Acetes indicus) Powder as Alternative and Sustainable Food for the Double Burden of Malnutrition

Authors: Galuh Asri Bestari, Hajar Shofiyya

Abstract:

Double burden of malnutrition (DBM) has been a global problem in these last decades occurs in both developed and developing countries. Overweight in adults and stunting among preschool children have dramatically increased and become the main problems of malnutrition that should be solved immediately since they are directly related with the health status and productivity. Reformulation of food product by using the local sea resources called terasi shrimp (Acetes indicus) has a potential possibility in facing the DBM. A study was carried out in Indonesia to determine the acceptability of terasi shrimp powder through sensory evaluation. Terasi shrimps were processed into powder form through sun drying and pounding methods. The powder form was directly added in food as alternative seasonings and tested among stunted and normal preschool children. Meanwhile, a further processing method is given to the shrimp powder tested in overweight and normal-weighed adults. The shrimp powder was mixed with sago flour and formed into balls, then steamed for 15-20 minutes, and finally served as alternative snacks. Based on the sensory evaluation, the shrimp powder has a good acceptance in taste (54%), shape (60%), and color properties (63%), while the shrimp balls has a good acceptance in size (65%), shape (50%), color (48%), taste (40%), and texture (36%). Terasi shrimp powder can be stored for a month in room temperature. In addition, carried out chemical analysis revealed that terasi shrimp (Acetes indicus) has higher percentage of protein, calcium, and iron than other animal sources, but conversely contains zero sodium and very low percentage of fat. Terasi shrimp’s shell also contains a substance called chitosan which acts by forming gels in the intestinal tract to entrap lipids, thus interfering with their absorption. After going through some processing methods, the shrimp powder and balls did not show any significant changes in their nutrient contents. So that, terasi shrimp powder is good to be consumed not only by overweight adults, but also by children to support their optimum growth. Intervention of terasi shrimp powder should be implemented step by step from national up to global governance program to face the DBM.

Keywords: Acetes indicus, alternative food, double burden of malnutrition, sensory evaluation

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5258 Measurement of Reverse Flow Generated at Cold Exit of Vortex Tube

Authors: Mohd Hazwan bin Yusof, Hiroshi Katanoda

Abstract:

In order to clarify the structure of the cold flow discharged from the vortex tube (VT), the pressure of the cold flow was measured, and a simple flow visualization technique using a 0.75 mm-diameter needle and an oily paint is made to study the reverse flow at the cold exit. It is clear that a negative pressure and positive pressure region exist at a certain pressure and cold fraction area, and that a reverse flow is observed in the negative pressure region.

Keywords: flow visualization, pressure measurement, reverse flow, vortex tube

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5257 Developing HRCT Criterion to Predict the Risk of Pulmonary Tuberculosis

Authors: Vandna Raghuvanshi, Vikrant Thakur, Anupam Jhobta

Abstract:

Objective: To design HRCT criterion to forecast the threat of pulmonary tuberculosis. Material and methods: This was a prospective study of 69 patients with clinical suspicion of pulmonary tuberculosis. We studied their medical characteristics, numerous separate HRCT-results, and a combination of HRCT findings to foresee the danger for PTB by utilizing univariate and multivariate investigation. Temporary HRCT diagnostic criteria were planned in view of these outcomes to find out the risk of PTB and tested these criteria on our patients. Results: The results of HRCT chest were analyzed, and Rank was given from 1 to 4 according to the HRCT chest findings. Sensitivity, specificity, positive predictive value, and negative predictive value were calculated. Rank 1: Highly suspected PTB. Rank 2: Probable PTB Rank 3: Nonspecific or difficult to differentiate from other diseases Rank 4: Other suspected diseases • Rank 1 (Highly suspected TB) was present in 22 (31.9%) patients, all of them finally diagnosed to have pulmonary tuberculosis. The sensitivity, specificity, and negative likelihood ratio for RANK 1 on HRCT chest was 53.6%, 100%, and 0.43, respectively. • Rank 2 (Probable TB) was present in 13 patients, out of which 12 were tubercular, and 1 was non-tubercular. • The sensitivity, specificity, positive likelihood ratio, and negative likelihood ratio of the combination of Rank 1 and Rank 2 was 82.9%, 96.4%, 23.22, and 0.18, respectively. • Rank 3 (Non-specific TB) was present in 25 patients, and out of these, 7 were tubercular, and 18 were non-tubercular. • When all these 3 ranks were considered together, the sensitivity approached 100% however, the specificity reduced to 35.7%. The positive likelihood ratio and negative likelihood ratio were 1.56 and 0, respectively. • Rank 4 (Other specific findings) was given to 9 patients, and all of these were non-tubercular. Conclusion: HRCT is useful in selecting individuals with greater chances of pulmonary tuberculosis.

Keywords: pulmonary, tuberculosis, multivariate, HRCT

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5256 Efficient Ni(II)-Containing Layered Triple Hydroxide-Based Catalysts: Synthesis, Characterisation and Their Role in the Heck Reaction

Authors: Gabor Varga, Krisztina Karadi, Zoltan Konya, Akos Kukovecz, Pal Sipos, Istvan Palinko

Abstract:

Nickel can efficiently replace palladium in the Heck, Suzuki and Negishi reactions. This study focuses on the synthesis and catalytic application of Ni(II)-containing layered double hydroxides (LDHs) and layered triple hydroxides (LTHs). Our goals were to incorporate Ni(II) ions among the layers of LDHs or LTHs, or binding it to their surface or building it into their layers in such a way that their catalytic activities are maintained or even increased. The LDHs and LTHs were prepared by the co-precipitation method using ethylene glycol as co-solvent. In several cases, post-synthetic modifications (e.g., thermal treatment) were performed. After optimizing the synthesis conditions, the composites displayed good crystallinity and were free of byproducts. The success of the syntheses and the post-synthetic modifications was confirmed by relevant characterization methods (XRD, SEM, SEM-EDX and combined IR techniques). Catalytic activities of the produced and well-characterized solids were investigated through the Heck reaction. The composites behaved as efficient, recyclable catalysts in the Heck reaction between 4-bromoanisole and styrene. Through varying the reaction parameters, we were able to obtain acceptable conversions under mild conditions. Our study highlights the possibility of the application of Ni(II)-containing composites as efficient catalysts in coupling reactions.

Keywords: layered double hydroxide, layered triple hydroxide, heterogeneous catalysis, heck reaction

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5255 Balanced Ischemia Misleading to a False Negative Myocardial Perfusion Imaging (Stress) Test

Authors: Devam Sheth

Abstract:

Nuclear imaging with stress myocardial perfusion (stress test) is the preferred first line investigation for noninvasive evaluation of ischaemic heart condition. The sensitivity of this test is close to 90 % making it a very reliable test. However, rarely it gives a false negative result which can be explained by the phenomenon termed as “balanced ischaemia”. We present the case of a 78 year Caucasian female without any significant past cardiac history, who presents with chest pain and shortness of breath since one day. The initial ECG and cardiac enzymes were non-impressive. Few hours later, she had some substernal chest pain along with some ST segment depression in the lateral leads. Stress test comes back negative for any significant perfusion defects. However, given her typical symptoms, she underwent a cardiac catheterization which revealed significant triple vessel disease mandating her to get a bypass surgery. This unusual phenomenon of false nuclear stress test in the setting of positive ECG changes can be explained only by balanced ischemia wherein due to global myocardial ischemia, the stress test fails to reveal relative perfusion defects in the affected segments.

Keywords: balanced, false positive, ischemia, myocardial perfusion imaging

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5254 Drastic Increase of Wave Dissipation within Metastructures Having Negative Stiffness Inclusions

Authors: D. Chronopoulos, I. Antoniadis, V. Spitas, D. Koulocheris, V. Polenta

Abstract:

A concept of a simple linear oscillator, incorporating a negative stiffness element is demonstrated to exhibit extraordinary damping properties. This oscillator shares the same overall (static) stiffness, the same mass and the same damping element with a reference classical linear SDOF oscillator. However, it differs from the original SDOF oscillator by appropriately redistributing the component spring stiffness elements and by re-allocating the damping element. Despite the fact that the proposed oscillator incorporates a negative stiffness element, it is designed to be both statically and dynamically stable. Once such an oscillator is optimally designed, it is shown to exhibit an extraordinary apparent damping ratio, which is even several orders of magnitude higher than that of the original SDOF system, especially in cases where the original damping of the SDOF system is low. This damping behavior is not a result of a novel additional extraordinary energy dissipation mechanism, but a result of the phase difference between the positive and the negative stiffness elastic forces, which is in turn a consequence of the proper re-distribution of the stiffness and the damper elements. This fact ensures that an adequate level of elastic forces exists throughout the entire frequency range, able to counteract the inertial and the excitation forces. Next, Acoustic or Phononic Meta-materials are considered, in which one atom is replaced by the concept of the above simple linear oscillator. The results indicate that not only the damping of the meta-material verifies and exceeds the one expected from the so-called "meta-damping" behavior, but also that the band gap of the meta-material can be significantly increased.

Keywords: wave propagation, periodic structures, wave damping, mechanical engineering

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5253 Analyze the Effect of TETRA, Terrestrial Trunked Radio, Signal on the Health of People Working in the Gas Refinery

Authors: Mohammad Bagher Heidari, Hefzollah Mohammadian

Abstract:

TETRA (Terrestrial Trunked Radio) is a digital radio communication standard, which has been implemented in several different parts of the gas refinery ninth (phase 12th) by South Pars Gas Complex. Studies on possible impacts on the users' health considering different exposure conditions are missing. Objectives: To investigate possible acute effects of electromagnetic fields (EMF) of two different levels of TETRA hand-held transmitter signals on cognitive function and well-being in healthy young males. Methods: In the present double-blind cross-over study possible effects of short-term (2.5 h) EMF exposure of handset-like signals of TETRA (450 - 470 MHz) were studied in 30 healthy male participants (mean ± SD: 25.4 ±2.6 years). Individuals were tested on nine study days, on which they were exposed to three different exposure conditions (Sham, TETRA 1.5 W/kg and TETRA 10.0 W/kg) in a randomly assigned and balanced order. Participants were tested in the afternoon at a fixed timeframe. Results: Attention remained unchanged in two out of three tasks. In the working memory, significant changes were observed in two out of four subtasks. Significant results were found in 5 out of 35 tested parameters, four of them led to an improvement in performance. Mood, well-being and subjective somatic complaints were not affected by TETRA exposure. Conclusions: The results of the present study do not indicate a negative impact of a short-term EMF- effect of TETRA on cognitive function and well-being in healthy young men.

Keywords: TETRA (terrestrial trunked radio), electromagnetic fields (EMF), mobile telecommunication health research (MTHR), antenna

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5252 Evaluation of Negative Air Ions in Bioaerosol Removal: Indoor Concentration of Airborne Bacterial and Fungal in Residential Building in Qom City, Iran

Authors: Z. Asadgol, A. Nadali, H. Arfaeinia, M. Khalifeh Gholi, R. Fateh, M. Fahiminia

Abstract:

The present investigation was conducted to detect the type and concentrations of bacterial and fungal bioaerosols in one room (bedroom) of each selected residential building located in different regions of Qom during February 2015 (n=9) to July 2016 (n=11). Moreover, we evaluated the efficiency of negative air ions (NAIs) in bioaerosol reduction in indoor air in residential buildings. In the first step, the mean concentrations of bacterial and fungal in nine sampling sites evaluated in winter were 744 and 579 colony forming units (CFU)/m3, while these values were 1628.6 and 231 CFU/m3 in the 11 sampling sites evaluated in summer, respectively. The most predominant genera between bacterial and fungal in all sampling sites were detected as Micrococcus spp. and Staphylococcus spp. and also, Aspergillus spp. and Penicillium spp., respectively. The 95% and 45% of sampling sites have bacterial and fungal concentrations over the recommended levels, respectively. In the removal step, we achieved a reduction with a range of 38% to 93% for bacterial genera and 25% to 100% for fungal genera by using NAIs. The results suggested that NAI is a highly effective, simple and efficient technique in reducing the bacterial and fungal concentration in the indoor air of residential buildings.

Keywords: bacterial, fungal, negative air ions (NAIs), indoor air, Iran

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5251 Parametric Study and Design on under Reamed Pile - An Experimental and Numerical Study

Authors: S. Chandrakaran, Aarthy D.

Abstract:

Abstract: Under reamed piles are piles which are of different types like bored cast in-situ pile or bored compaction concrete piles where one or more bulbs are provided. In this paper, the design procedure of under reamed pile by both experimental study and numerical study using PLAXIS 3D Foundation software was studied. The soil chosen for study was M Sand. The Single and double under reamed pile modelling was made using mild steel. The pile load test experiment was conducted in the laboratory and the ultimate compression load for 25 mm settlement on single and double under reamed pile was observed and finally the result was compared with conventional pile (pile without bulb). The parametric influence on under reamed pile was studied by varying the geometrical parameters like diameter of bulbs, spacing between bulbs, position of bulbs and number of bulbs. The results of the numerical model showed that when the diameter of bulb D u =2.5D, the ultimate compression load for an under-reamed pile with a single bulb increased by 55 % compared to a pile without a bulb. It was observed that when the spacing between the bulbs was S=6D u with three different positions of bulb from bottom of pile as D u , 2D u and 3D u , the ultimate compression load increased by 88%, 94% and 73 % respectively, compared to the ultimate compression load for 25 mm settlement on conventional pile and if spacing was more than 6D u , ultimate compression load for 25 mm settlement started to decrease. It was observed that when the bucket length was more than 2D u , the ultimate compression

Keywords: load capcity, under remed bulb . sand, model study, sand

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5250 The Experiences of Hong Kong Chinese Divorced Wives in Facing the Cancer Death of Their Ex-Husbands

Authors: M. L. Yeung

Abstract:

With the surge of divorce rate and male cancer onset/death rates, the phenomenon of divorced wives in the facing cancer death of their ex-husbands is not uncommon in Hong Kong. Yet, there is a dearth of study on the experiences of bereaved-divorced wives in the Hong Kong cultural context. This project fills the knowledge gap by conducting a qualitative study for having interviewed four bereaved ex-wives, who returned to ex-husbands’ end-of-life caregiving and eventually grieved for the ex-spousal’s death. From the perspectives of attachment theory and disenfranchised grief in the Hong Kong cultural context, a ‘double-loss’ experience is found in which interviewees suffer from the first loss of divorce and the second loss of ex-husbands’ death. Traumatic childhood experiences, attachment needs, role ambiguity, unresolved emotions and unrecognized grief are found significant in their lived experiences which alert the ‘double-loss’ is worthy of attention. Extending a family-centered end-of-life and bereavement care services to divorced couples is called for, in which validation on the attachment needs, ex-couple reconciliation, and acknowledgement on the disenfranchised grief are essential for social work practice on this group of clienteles specifically in Hong Kong cultural context.

Keywords: changing family, disenfranchised grief, divorce, ex-spousal death, marriage

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5249 Nano-Sized Iron Oxides/ZnMe Layered Double Hydroxides as Highly Efficient Fenton-Like Catalysts for Degrading Specific Pharmaceutical Agents

Authors: Marius Sebastian Secula, Mihaela Darie, Gabriela Carja

Abstract:

Persistent organic pollutant discharged by various industries or urban regions into the aquatic ecosystems represent a serious threat to fauna and human health. The endocrine disrupting compounds are known to have toxic effects even at very low values of concentration. The anti-inflammatory agent Ibuprofen is an endocrine disrupting compound and is considered as model pollutant in the present study. The use of light energy to accomplish the latest requirements concerning wastewater discharge demands highly-performant and robust photo-catalysts. Many efforts have been paid to obtain efficient photo-responsive materials. Among the promising photo-catalysts, layered double hydroxides (LDHs) attracted significant consideration especially due to their composition flexibility, high surface area and tailored redox features. This work presents Fe(II) self-supported on ZnMeLDHs (Me =Al3+, Fe3+) as novel efficient photo-catalysts for Fenton-like catalysis. The co-precipitation method was used to prepare ZnAlLDH, ZnFeAlLDH and ZnCrLDH (Zn2+/Me3+ = 2 molar ratio). Fe(II) was self-supported on the LDHs matrices by using the reconstruction method, at two different values of weight concentration. X-ray diffraction (XRD), thermogravimetric analysis (TG/DTG), Fourier transform infrared (FTIR) and transmission electron microscopy (TEM) were used to investigate the structural, textural, and micromorphology of the catalysts. The Fe(II)/ZnMeLDHs nano-hybrids were tested for the degradation of a model pharmaceutical agent, the anti-inflammatory agent ibuprofen, by photocatalysis and photo-Fenton catalysis, respectively. The results point out that the embedment Fe(II) into ZnFeAlLDH and ZnCrLDH lead to a slight enhancement of ibuprofen degradation by light irradiation, whereas in case of ZnAlLDH, the degradation process is relatively low. A remarkable enhancement of ibuprofen degradation was found in the case of Fe(II)/ZnMeLDHs by photo-Fenton process. Acknowledgements: This work was supported by a grant of the Romanian National Authority for Scientific Research and Innovation, CNCS - UEFISCDI, project number PN-II-RU-TE-2014-4-0405.

Keywords: layered double hydroxide, heterogeneous Fenton, micropollutant, photocatalysis

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5248 The Impact of Psychopathology Course on Students' Attitudes towards Mental Illness

Authors: Lorato Itumeleng Kenosi

Abstract:

Background: Negative attitudes towards the mentally ill are widespread and a course for concern as they have a detrimental impact on individuals affected by mental illness. A possible avenue for changing attitudes towards mental illness is through mental health literacy. In a college or university setting, an abnormal psychology course may be introduced in an attempt to change student’s attitudes towards the mentally ill. Objective: To determine if and how students’ attitudes towards the mentally ill change as a result of taking a course in abnormal psychology. Methods: Twenty nine (29) students were recruited from an abnormal psychology class at the University of Botswana. Attitude Scale for Mental Illness (ASMI) questionnaire was administered to participants at the beginning and end of the semester. SPSS was employed to analyze data. Pooled means were used to determine whether the student’s attitudes towards mental illness were negative or positive. A mean of 2.5 translated to negative attitude for both total attitude and attitudes in different domains of the scale. Paired sample t-test was then used to assess whether any changes noted in attitudes were statistically significant or not. Statistical significance was assumed at p < 0.05. Results: Students’ general attitude towards mental illness remained positive although the pooled mean value increased from 2.08 to 2.24. The change was not statistically significant. In relation to different sub scales, the values of the pooled means for all the sub scales showed an increase although the changes were not statistically significant except for the Stereotyping sub scale (p = 0.031). The stereotyping domain reflected a statistically significant change in student’s attitude from positive attitude to negative (X² = 2.06 to X² = 2.55). For the pessimistic prediction domain, students consistently showed a negative attitude (X² = 3.34 to X² = 3.55). The other 4 domains indicated that students had positive attitude toward mentally ill throughout. Discussion: Abnormal psychology students have a positive attitude towards the mentally ill generally. This could be attributed to the fact that all students in the abnormal psychology course are majoring in psychology and research has shown that interest in psychology can affect one’s attitude towards mental illness. The students continuously held the view that people with mental illness are unlikely to improve as evidenced by a high score for Pessimistic prediction domain for both pre and post-test. Students initially had no stereotyping attitude towards the mentally ill, but at the end of the course, they were of the opinion that people with mental illness can be defined in a certain behavioural pattern and mental ability. This results could be an indication that students have learnt well how to differentiate abnormal from normal behaviour not necessarily that students had developed a negative attitude. Conclusion: A course in abnormal psychology does have an impact on the students’ attitudes towards the mentally ill. The impact does not solely depend on knowledge of mental illness but also on several other factors such as contact with the mentally ill, interest in psychology, and teaching methods. However, it should be noted that sometimes improved knowledge in mental illness can be misunderstood for a negative attitude. For example, stereotyping attitudes may be a reflection of the ability to differentiate between abnormal and normal behaviour.

Keywords: attitudes, mental illness, psychopathology, students

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5247 A Fuzzy Control System for Reducing Urban Stormwater Runoff by a Stormwater Storage Tank

Authors: Pingping Zhang, Yanpeng Cai, Jianlong Wang

Abstract:

Stormwater storage tank (SST) is a popular low impact development technology for reducing stormwater runoff in the construction of sponge city. At present, it is difficult to perform the automatic control of SST for reducing peak flow. In this paper, fuzzy control was introduced into the peak control of SST to improve the efficiency of reducing stormwater runoff. Firstly, the design of SST was investigated. A catchment area and a return period were assumed, a SST model was manufactured, and then the storage capacity of the SST was verified. Secondly, the control parameters of the SST based on reducing stormwater runoff were analyzed, and a schematic diagram of real-time control (RTC) system based on peak control SST was established. Finally, fuzzy control system of a double input (flow and water level) and double output (inlet and outlet valve) was designed. The results showed that 1) under the different return periods (one year, three years, five years), the SST had the effect of delayed peak control and storage by increasing the detention time, 2) rainfall, pipeline flow, the influent time and the water level in the SST could be used as RTC parameters, and 3) the response curves of flow velocity and water level fluctuated very little and reached equilibrium in a short time. The combination of online monitoring and fuzzy control was feasible to control the SST automatically. This paper provides a theoretical reference for reducing stormwater runoff and improving the operation efficiency of SST.

Keywords: stormwater runoff, stormwater storage tank, real-time control, fuzzy control

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5246 The Effect of Role Conflict, Role Ambiguity and Job Satisfaction on Auditor Performance

Authors: Binti Shofiatul Jannah, Hans Wakhida Rakhmatullah

Abstract:

This paper aims to examine the influence of role conflict, role ambiguity and job satisfaction on auditor performance. This study uses survey method using a questionnaire to collect the data. The questionnaires distributes were 104 respondents. The respondents are auditors who work for public accounting firms in East Java. Partial Least Square (PLS) with program SmartPLS version 2.0 were used to hypothesis testing. The result shows that: (1) there is no negative influence of role conflict on auditor performance; (2) there is negative influence of role ambiguity on auditor performance; (3) there is positive influence of job satisfaction on auditor performance.

Keywords: role conflict, role ambiguity, job satisfaction, performance

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5245 A Computational Analysis of Gas Jet Flow Effects on Liquid Aspiration in the Collison Nebulizer

Authors: James Q. Feng

Abstract:

Pneumatic nebulizers (as variations based on the Collison nebulizer) have been widely used for producing fine aerosol droplets from a liquid material. As qualitatively described by many authors, the basic working principle of those nebulizers involves utilization of the negative pressure associated with an expanding gas jet to syphon liquid into the jet stream, then to blow and shear into liquid sheets, filaments, and eventually droplets. But detailed quantitative analysis based on fluid mechanics theory has been lacking in the literature. The purpose of present work is to investigate the nature of negative pressure distribution associated with compressible gas jet flow in the Collison nebulizer by a computational fluid dynamics (CFD) analysis, using an OpenFOAM® compressible flow solver. The value of the negative pressure associated with a gas jet flow is examined by varying geometric parameters of the jet expansion channel adjacent to the jet orifice outlet. Such an analysis can provide valuable insights into fundamental mechanisms in liquid aspiration process, helpful for effective design of the pneumatic atomizer in the Aerosol Jet® direct-write system for micro-feature, high-aspect-ratio material deposition in additive manufacturing.

Keywords: collison nebulizer, compressible gas jet flow, liquid aspiration, pneumatic atomization

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5244 A Socio-Cultural Approach to Implementing Inclusive Education in South Africa

Authors: Louis Botha

Abstract:

Since the presentation of South Africa’s inclusive education strategy in Education White Paper 6 in 2001, very little has been accomplished in terms of its implementation. The failure to achieve the goals set by this policy document is related to teachers lacking confidence and knowledge about how to enact inclusive education, as well as challenges of inflexible curricula, limited resources in overcrowded classrooms, and so forth. This paper presents a socio-cultural approach to addressing these challenges of implementing inclusive education in the South African context. It takes its departure from the view that inclusive education has been adequately theorized and conceptualized in terms of its philosophical and ethical principles, especially in South African policy and debates. What is missing, however, are carefully theorized, practically implementable research interventions which can address the concerns mentioned above. Drawing on socio-cultural principles of learning and development and on cultural-historical activity theory (CHAT) in particular, this paper argues for the use of formative interventions which introduce appropriately constructed mediational artifacts that have the potential to initiate inclusive practices and pedagogies within South African schools and classrooms. It makes use of Vygotsky’s concept of double stimulation to show how the proposed artifacts could instigate forms of transformative agency which promote the adoption of inclusive cultures of learning and teaching.

Keywords: cultural-historical activity theory, double stimulation, formative interventions, transformative agency

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5243 Obtainment of Systems with Efavirenz and Lamellar Double Hydroxide as an Alternative for Solubility Improvement of the Drug

Authors: Danilo A. F. Fontes, Magaly A. M.Lyra, Maria L. C. Moura, Leslie R. M. Ferraz, Salvana P. M. Costa, Amanda C. Q. M. Vieira, Larissa A. Rolim, Giovanna C. R. M. Schver, Ping I. Lee, Severino Alves-Júnior, José L. Soares-Sobrinho, Pedro J. Rolim-Neto

Abstract:

Efavirenz (EFV) is a first-choice drug in antiretroviral therapy with high efficacy in the treatment of infection by Human Immunodeficiency Virus, which causes Acquired Immune Deficiency Syndrome (AIDS). EFV has low solubility in water resulting in a decrease in the dissolution rate and, consequently, in its bioavailability. Among the technological alternatives to increase solubility, the Lamellar Double Hydroxides (LDH) have been applied in the development of systems with poorly water-soluble drugs. The use of analytical techniques such as X-Ray Diffraction (XRD), Infrared Spectroscopy (IR) and Differential Scanning Calorimetry (DSC) allowed the elucidation of drug interaction with the lamellar compounds. The objective of this work was to characterize and develop the binary systems with EFV and LDH in order to increase the solubility of the drug. The LDH-CaAl was synthesized by the method of co-precipitation from salt solutions of calcium nitrate and aluminum nitrate in basic medium. The systems EFV-LDH and their physical mixtures (PM) were obtained at different concentrations (5-60% of EFV) using the solvent technique described by Takahashi & Yamaguchi (1991). The characterization of the systems and the PM’s was performed by XRD techniques, IR, DSC and dissolution test under non-sink conditions. The results showed improvements in the solubility of EFV when associated with LDH, due to a possible change in its crystal structure and formation of an amorphous material. From the DSC results, one could see that the endothermic peak at 173°C, temperature that correspond to the melting process of EFZ in the crystal form, was present in the PM results. For the EFZ-LDH systems (with 5, 10 and 30% of drug loading), this peak was not observed. XRD profiles of the PM showed well-defined peaks for EFV. Analyzing the XRD patterns of the systems, it was found that the XRD profiles of all the systems showed complete attenuation of the characteristic peaks of the crystalline form of EFZ. The IR technique showed that, in the results of the PM, there was the appearance of one band and overlap of other bands, while the IR results of the systems with 5, 10 and 30% drug loading showed the disappearance of bands and a few others with reduced intensity. The dissolution test under non-sink conditions showed that systems with 5, 10 and 30% drug loading promoted a great increase in the solubility of EFV, but the system with 10% of drug loading was the only one that could keep substantial amount of drug in solution at different pHs.

Keywords: Efavirenz, Lamellar Double Hydroxides, Pharmaceutical Techonology, Solubility

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5242 Relationship between Smartphone Addiction and Academic Performance among University Students

Authors: Arooba Azam Khan

Abstract:

The present study aims to focus on the relationship between smartphone addiction and academic performance of students along with social networking sites, overuse of smartphone, GPA’s and time management skills as their sub-variables. In this world of technology, the smartphone becomes a vital part of everyone’s life. The addiction of smartphones has both negative and positive impact on young people (students). Students keep themselves busy with smartphones without noticing that smartphone addiction is creating a negative impact on their social, academic, and personal lives. A quantitative approach was used to collect data through questionnaire from 360 students of two private universities in Pakistan in summer 2017. The target age group was 19-24 studying in Bachelors programmes. Data were analyzed by using SPSS (version 20), linear correlation and regression tests were applied. Results reveal that there is a negative relationship between smartphone addiction and academic performance. Moreover, it has been proved that students with good time management skills achieve high grades/GPA’s than those who have poor time management skills. From the findings, the researcher suggests that students should spend their time wisely and use their smartphones for educational purpose. However, students need training and close monitoring to get benefits out of smartphones use.

Keywords: smartphone addiction, academic performance, time management skills, quantitative research

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5241 Self-Assembled ZnFeAl Layered Double Hydroxides as Highly Efficient Fenton-Like Catalysts

Authors: Marius Sebastian Secula, Mihaela Darie, Gabriela Carja

Abstract:

Ibuprofen is a non-steroidal anti-inflammatory drug (NSAIDs) and is among the most frequently detected pharmaceuticals in environmental samples and among the most widespread drug in the world. Its concentration in the environment is reported to be between 10 and 160 ng L-1. In order to improve the abatement efficiency of this compound for water source prevention and reclamation, the development of innovative technologies is mandatory. AOPs (advanced oxidation processes) are known as highly efficient towards the oxidation of organic pollutants. Among the promising combined treatments, photo-Fenton processes using layered double hydroxides (LDHs) attracted significant consideration especially due to their composition flexibility, high surface area and tailored redox features. This work presents the self-supported Fe, Mn or Ti on ZnFeAl LDHs obtained by co-precipitation followed by reconstruction method as novel efficient photo-catalysts for Fenton-like catalysis. Fe, Mn or Ti/ZnFeAl LDHs nano-hybrids were tested for the degradation of a model pharmaceutical agent, the anti-inflammatory agent ibuprofen, by photocatalysis and photo-Fenton catalysis, respectively, by means of a lab-scale system consisting of a batch reactor equipped with an UV lamp (17 W). The present study presents comparatively the degradation of Ibuprofen in aqueous solution UV light irradiation using four different types of LDHs. The newly prepared Ti/ZnFeAl 4:1 catalyst results in the best degradation performance. After 60 minutes of light irradiation, the Ibuprofen removal efficiency reaches 95%. The slowest degradation of Ibuprofen solution occurs in case of Fe/ZnFeAl 4:1 LDH, (67% removal efficiency after 60 minutes of process). Evolution of Ibuprofen degradation during the photo Fenton process is also studied using Ti/ZnFeAl 2:1 and 4:1 LDHs in the presence and absence of H2O2. It is found that after 60 min the use of Ti/ZnFeAl 4:1 LDH in presence of 100 mg/L H2O2 leads to the fastest degradation of Ibuprofen molecule. After 120 min, both catalysts Ti/ZnFeAl 4:1 and 2:1 result in the same value of removal efficiency (98%). In the absence of H2O2, Ibuprofen degradation reaches only 73% removal efficiency after 120 min of degradation process. Acknowledgements: This work was supported by a grant of the Romanian National Authority for Scientific Research and Innovation, CNCS - UEFISCDI, project number PN-II-RU-TE-2014-4-0405.

Keywords: layered double hydroxide, advanced oxidation process, micropollutant, heterogeneous Fenton

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5240 Prevalence of Extended Spectrum of Beta Lactamase Producers among Gram Negative Uropathogens

Authors: Y. V. S. Annapurna, V. V. Lakshmi

Abstract:

Urinary tract infection (UTI) is one of the most common infectious diseases at the community level with a high rate of morbidity . This is further augmented by increase in the number of resistant and multi resistant strains of bacteria particularly by those producing Extended spectrum of beta lactamases. The present study was aimed at analysis of antibiograms of E.coli and Klebsiella sp causing urinary tract infections. Between November 2011 and April 2013, a total of 1120 urine samples were analyzed,. Antibiotic sensitivity testing was done with 542(48%) isolates of E.coli and 446(39%) of Klebsiella sp using the standard disc diffusion method against eleven commonly used antibiotics .Organisms showed high susceptibility to Amikacin and Netilimicin and low susceptibility to Cephalosporins. MAR index was calculated for the multidrug resistant strains. Maximum MAR index detected among the isolates was 0.9. Phenotypic identification for ESBL production was confirmed by double disk synergy test (DDST) according to CLSI guidelines. Plasmid profile of the isolates was carried out using alkaline hydrolysis method. Agarose-gel electrophoresis showed presence of high-molecular weight plasmid DNA among the ESBL strains. This study emphasizes the importance of indiscriminate use of antibiotics which if discontinued, in turn would prevent further development of bacterial drug resistance. For this, a proper knowledge of susceptibility pattern of uropathogens is necessary before prescribing empirical antibiotic therapy and it should be made mandatory.

Keywords: escherichia coli, extended spectrum of beta lactamase, Klebsiella spp, Uropathogens

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5239 A Crystal Plasticity Approach to Model Dynamic Strain Aging

Authors: Burak Bal, Demircan Canadinc

Abstract:

Dynamic strain aging (DSA), resulting from the reorientation of C-Mn clusters in the core of dislocations, can provide a strain hardening mechanism. In addition, in Hadfield steel, negative strain rate sensitivity is observed due to the DSA. In our study, we incorporated dynamic strain aging onto crystal plasticity computations to predict the local instabilities and corresponding negative strain rate sensitivity. Specifically, the material response of Hadfield steel was obtained from monotonic and strain-rate jump experiments under tensile loading. The strain rate range was adjusted from 10⁻⁴ to 10⁻¹s ⁻¹. The crystal plasticity modeling of the material response was carried out based on Voce-type hardening law and corresponding Voce hardening parameters were determined. The solute pinning effect of carbon atom was incorporated to crystal plasticity simulations at microscale level by computing the shear stress contribution imposed on an arrested dislocation by carbon atom. After crystal plasticity simulations with modifying hardening rule, which takes into account the contribution of DSA, it was seen that the model successfully predicts both the role of DSA and corresponding strain rate sensitivity.

Keywords: crystal plasticity, dynamic strain aging, Hadfield steel, negative strain rate sensitivity

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5238 A Study on How to Influence Players Interactive Behavior of Victory or Defeat in Party Games

Authors: Shih-Chieh Liao, Cheng-Yan Shuai

Abstract:

"Party game" is a game mode that enables players to maintain a good social and interactive experience. The common game modes include Teamwork, Team competitive, Independent competitive, Battle Royale. Party games are defined as a game with easy rules, easy to play, quickly spice up a party, and support four to six players. It also needs to let the player feel satisfied no matter victory or defeat. However, players may feel negative or angry when the game is imbalanced, especially when they play with teammates. Some players care about winning or losing, and they will blame it on the game mechanics. What is more serious is that the player will cause the argument, which is unnecessary. These behaviors that trigger quarrels and negative emotions often originate from the player's determination of the victory and the ratio of victory during the competition. In view of this, our research invited a group of subjects to the experiment, which is going to inspect player’s emotions by Electromyography (EMG) and Electrodermal Activity (EDA) when they are playing party games with others. When a player wins or loses, the negative and positive feeling will be recorded from the game beginning to the end. At the same time, physiologic and emotional reactions are also being recorded in each part of the game. The game will be designed as telling the interaction when players are in the quest of a party game. The experiment content includes the emotional changes affected by the physiological values of game victory and defeat between “player against friend” and “player against stranger.” Through this experiment, the balance between winners and losers lies in the basis of good game interaction and game interaction in the game and explore the emotional positive and negative effects caused by the result of the party game. The result shows that “player against friend” has a significant negative emotion and significant positive emotion at “player against stranger.” According to the result, the player's experience will be affected with winning rate or form when they play the party game. We suggest the developer balance the game with our experiment method to let players get a better experience.

Keywords: party games, biofeedback, emotional responses, user experience, game design

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5237 Toxic Dyes Removal in Aqueous Solution Using Calcined and Uncalcined Anionic Clay Zn/Al+Fe

Authors: Bessaha Hassiba, Bouraada Mohamed

Abstract:

Layered double hydroxide with Zn/(Al+Fe) molar ratio of 3:1 was synthesized by co-precipitation method and their calcined product was obtained by heating treatment of ZAF-HT at 500°C. The calcined and uncalcined materials were used to remove weak acid dyes: indigo carmine (IC) and green bezanyl-F2B (F2B) in aqueous solution. The synthesized materials were characterized by XRD, SEM, FTIR and TG/DTA analysis confirming the formation of pure layered structure of ZAF-HT, the destruction of the original structure after calcination and the intercalation of the dyes molecules. Moreover, the interlayer distance increases from 7.645 Å in ZAF-HT to 19.102 Å after the dyes sorption. The dose of the adsorbents was chosen 0.5 g/l while the initial concentrations were 250 and 750 mg/l for indigo carmine and green bezanyl-F2B respectively. The sorption experiments were carried out at ambient temperature and without adjusting the initial solution pH (pHi = 6.10 for IC and pHi = 5.01 for F2B). In addition, the maximum adsorption capacities obtained by ZAF-HT and CZAF for both dyes followed the order: CZAF-F2B (1501.4 mg.g-1) > CZAF-IC (617.3 mg.g-1) > ZAF-HT-IC (41.4 mg.g-1) > ZAF-HT-F2B (28.9 mg.g-1). The removal of indigo carmine and green bezanyl-F2B by ZAF-HT was due to the anion exchange and/or the adsorption on the surface. By using the calcined material (CZAF), the removal of the dyes was based on a particular property, called ‘memory effect’. CZAF recover the pristine structure in the presence anionic molecules such as acid dyes where they occupy the interlayer space. The sorption process was spontaneous in nature and followed pseudo-second-order. The isotherms showed that the removal of IC and F2B by ZAF-HT and CZAF were consistent with Langmiur model.

Keywords: acid dyes, adsorption, calcination, layered double hydroxides

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