Search results for: single minute exchange die

Authors: Robin L. Rohrer

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Introduction: Pre-natal or early childhood exposure to the medical radiation used in diagnosis or treatment is an identified risk for childhood cancers but can be difficult to document. The author developed a family questionnaire/interview form to identify possible exposures. Aims: This retrospective study examines pre-natal and early childhood medical radiation exposure in a cohort of children diagnosed with a solid tumor including brain tumors from 1985-2015 at the Children’s Hospital of Pittsburgh (CHP). The hospital is a tri-state regional referral center which treats about 150-180 new cases of cancer in children per year. About 70% are diagnosed with a solid tumor. Methods: Each consented family so far (approximately 50% of the cohort) has been interviewed in person or by the phone call. Medical staff and psycho- social staff referred patient families for the interview with the author. Results: Among the families interviewed to date at least one medical radiation exposure has been identified (pre-conception, pre-natal or early childhood) in over 70% of diagnosed children. These exposures have included pre-conception sinus or chest CT or X-ray in either parent, sinus CT or X-ray in the mother or diagnostic radiation of chest or abdomen in children. Conclusions: Exposures to medical radiation for a child later diagnosed with cancer may occur at several critical junctures. These exposures may well contribute to a ‘perfect storm’ in the still elusive causes of childhood cancer. The author plans to expand the study from 1975 to present to hopefully further document these junctures.

Keywords: pediatric, solid tumors, medical radiation, cancer

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Authors: A. Yanik, U. Aldemir

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This study investigates the benefits of implementing the semi-active devices in relation to passive viscous damping in the context of seismically isolated bridge structures. Since the intrinsically nonlinear nature of semi-active devices prevents the direct evaluation of Laplace transforms, frequency response functions are compiled from the computed time history response to sinusoidal and pulse-like seismic excitation. A simple semi-active control policy is used in regard to passive linear viscous damping and an optimal non-causal semi-active control strategy. The control strategy requires optimization. Euler-Lagrange equations are solved numerically during this procedure. The optimal closed-loop performance is evaluated for an idealized controllable dash-pot. A simplified single-degree-of-freedom model of an isolated bridge is used as numerical example. Two bridge cases are investigated. These cases are; bridge deck without the isolation bearing and bridge deck with the isolation bearing. To compare the performances of the passive and semi-active control cases, frequency dependent acceleration, velocity and displacement response transmissibility ratios T_a(w), T_v(w), and T_d(w) are defined. To fully investigate the behavior of the structure subjected to the sinusoidal and pulse type excitations, different damping levels are considered. Numerical results showed that, under the effect of external excitation, bridge deck with semi-active control showed better structural performance than the passive bridge deck case.

Keywords: bridge structures, passive control, seismic, semi-active control, viscous damping

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Authors: Rammah Abdlbagi, Similoluwa Biyi, Aakash Pai

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Introduction: Short-term ureteric stents are commonly placed after ureteroscopy procedures. The removal usually entails having a flexible cystoscopy, which entails a further invasive procedure. There are often delays in removing the stent as departments have limited cystoscopy availability. However, if stents with extraction strings are used, the patient or a clinician can remove them. The aim of the study is to assess the safety and effectiveness of the use of a stent with a string. Method: A retrospective, single-institution study was conducted over a three-month period. Twenty consecutive patients had ureteric stents with string insertion. Ten of the patients had a stent removal procedure previously with flexible cystoscopy. A validated questionnaire was used to assess outcomes. Primary outcomes included: dysuria, hematuria, urinary frequency, and disturbance of the patient’s daily activities. Secondary outcomes included pain experience during the stent removal. Result: Fifteen patients (75%) experienced hematuria and frequency. Two patients experienced pain and discomfort during the stent removal (10%). Two patients had experienced a disturbance in their daily activity (10%). All patients who had stent removal before using flexible cystoscopy preferred the removal of the stent using a string. None of the patients had stent displacement. The median stent dwell time was five days. Conclusion: Patient reported outcomes measures for the indwelling period of a stent with extraction string are equivalent to the published data on stents. Extraction strings mean that the stent dwell time can be reduced. The removal of the stent on extraction strings is more tolerable than the conventional stent.

Keywords: ureteric stent, string flexible cystoscopy, stent symptoms, validated questionnaire

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Authors: Paballo M. Moshupya, Tamiru A. Abiye, Ian Korir

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Mining and processing of naturally occurring radioactive materials could result in elevated levels of natural radionuclides in the environment. The aim of this study was to evaluate the radioactivity levels on a large scale in the West Rand District in South Africa, which is dominated by abandoned gold mine tailings and the consequential radiological exposures to members of the public. The activity concentrations of ²³⁸U, ²³²Th and 40K in mine tailings, soil and rocks were assessed using the BGO Super-Spec (RS-230) gamma spectrometer. The measured activity concentrations for ²³⁸U, ²³²Th and 40K in the studied mine tailings were found to range from 209.95 to 2578.68 Bq/kg, 19.49 to 108.00 Bq/kg and 31.30 to 626.00 Bq/kg, respectively. In surface soils, the overall average activity concentrations were found to be 59.15 Bq/kg, 34.91 and 245.64 Bq/kg for 238U, ²³²Th and 40K, respectively. For the rock samples analyzed, the mean activity concentrations were 32.97 Bq/kg, 32.26 Bq/kg and 351.52 Bg/kg for ²³⁸U, ²³²Th and 40K, respectively. High radioactivity levels were found in mine tailings, with ²³⁸U contributing significantly to the overall activity concentration. The external gamma radiation received from surface soil in the area is generally low, with an average of 0.07 mSv/y. The highest annual effective doses were estimated from the tailings dams and the levels varied between 0.14 mSv/y and 1.09 mSv/y, with an average of 0.51 mSv/y. In certain locations, the recommended dose constraint of 0.25 mSv/y from a single source to the average member of the public within the exposed population was exceeded, indicating the need for further monitoring and regulatory control measures specific to these areas to ensure the protection of resident members of the public.

Keywords: activity concentration, gold mine tailings, in-situ gamma spectrometry, radiological exposures

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Authors: Emil F. Khisamutdinov

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Development of functional materials undergoing structural transformations in response to an external stimulus such as environmental changes (pH, temperature, etc.), the presence of particular proteins, or short oligonucleotides are of great interest for a variety of applications ranging from medicine to electronics. The dynamic operations of most nucleic acid (NA) devices, including circuits, nano-machines, and biosensors, rely on networks of NA strand displacement processes in which an external or stimulus strand displaces a target strand from a DNA or RNA duplex. The rate of strand displacement can be greatly increased by the use of “toeholds,” single-stranded regions of the target complex to which the invading strand can bind to initiate the reaction, forming additional base pairs that provide a thermodynamic driving force for transformation. Herein, we developed a highly robust nanoparticle shape transition, sequentially transforming DNA polygons from one shape to another using the toehold-mediated DNA strand displacement technique. The shape transformation was confirmed by agarose gel electrophoresis and atomic force microscopy. Furthermore, we demonstrate that our approach is applicable for RNA shape transformation from triangle to square, which can be detected by fluorescence emission from malachite green binding RNA aptamer. Using gel-shift and fluorescence assays, we demonstrated efficient transformation occurs at isothermal conditions (37°C) that can be implemented within living cells as reporter molecules. This work is intended to provide a simple, cost-effective, and straightforward model for the development of biosensors and regulatory devices in nucleic acid nanotechnology.

Keywords: RNA nanotechnology, bionanotechnology, toehold mediated DNA switch, RNA split fluorogenic aptamers

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Authors: Mohammad Naeem Lakanwall, Jamshid Abdul-Ghafar

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Background: Endocrinopathies are a commonly occurring entity, particularly those of the thyroid gland; however, there is a lack of scientific literature from Afghanistan, a country with very limited health care facilities and resources. To our best knowledge, this is the first study aimed to describe the frequency of occurrence and factors associated with thyroid dysfunction in the Afghan population. The aim of this study is to estimate the frequency and to identify factors associated with thyroid dysfunction among individuals coming to a tertiary care facility in Kabul, Afghanistan. Methods: A cross-sectional study was conducted from July to Sep 2018 at the Department of Clinical Pathology, French Medical Institute for Mothers and Children (FMIC), Kabul, Afghanistan. Blood samples were obtained, serum TSH levels were analyzed, and the patients were divided into three diagnostic categories according to their serum TSH concentrations: 1) hypothyroidism, 2) hyperthyroidism, 3) normal. Results: A total of 127 individuals were included in the final analysis. The majority of study participants (77%) were females. A large number of the participants (92%) did not have a family history of thyroid dysfunction. 74% of the participants in the study had normal TSH levels classified as normal thyroid function, (14%) had lower TSH levels, and (12%) higher TSH levels, classified as hyper and hypothyroid, respectively. Conclusions: The findings of the current study showed a high frequency of thyroid dysfunctions from a single center. Further large-scale studies are needed to find out the prevalence and document this entity for better health outcomes in the country.

Keywords: Afghanistan, factors, frequency, hypothyroid, hyperthyroid, thyroid, thyroid stimulating hormone

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Authors: J. Samuel, S. Al-Enezi, A. Al-Banna

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High-density polyethylene reinforced with carbon nanofibers (HDPE/CNF) have been prepared via melt processing using dialkylimidazolium tetrafluoroborate (ionic liquid) as a dispersion agent. The prepared samples were characterized by thermogravimetric (TGA) and differential scanning calorimetric (DSC) analyses. The samples blended with imidazolium ionic liquid exhibit higher thermal stability. DSC analysis showed clear miscibility of ionic liquid in the HDPE matrix and showed single endothermic peak. The melt rheological analysis of HDPE/CNF composites was performed using an oscillatory rheometer. The influence of CNF and ionic liquid concentration (ranging from 0, 0.5, and 1 wt%) on the viscoelastic parameters was investigated at 200 °C with an angular frequency range of 0.1 to 100 rad/s. The rheological analysis shows the shear-thinning behavior for the composites. An improvement in the viscoelastic properties was observed as the nanofiber concentration increases. The progress in the modulus values was attributed to the structural rigidity imparted by the high aspect ratio CNF. The modulus values and complex viscosity of the composites increased significantly at low frequencies. Composites blended with ionic liquid exhibit slightly lower values of complex viscosity and modulus over the corresponding HDPE/CNF compositions. Therefore, reduction in melt viscosity is an additional benefit for polymer composite processing as a result of wetting effect by polymer-ionic liquid combinations.

Keywords: high-density polyethylene, carbon nanofibers, ionic liquid, complex viscosity

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Authors: Liubov Lutsyshyn, Yaroslava Zhukova

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Over the past twenty years, there has been a drastic change in the mode of nutrition in many countries which has been reflected in the development of new products, production techniques, and has also led to the expansion of sales markets for food products. Studies have shown that solution of the food safety problems is almost impossible without the active and systematic activity of organizations directly involved in the production, storage and sale of food products, as well as without management of end-to-end traceability and exchange of information. The aim of this research is development of the integrated system of the quality management and safety assurance based on the principles of HACCP, traceability and system approach with creation of an algorithm for the identification and monitoring of parameters of technological process of manufacture of cooked sausage products. Methodology of implementation of the integrated system based on the principles of HACCP, traceability and system approach during the manufacturing of cooked sausage products for effective provision for the defined properties of the finished product has been developed. As a result of the research evaluation technique and criteria of performance of the implementation and operation of the system of the quality management and safety assurance based on the principles of HACCP have been developed and substantiated. In the paper regularities of influence of the application of HACCP principles, traceability and system approach on parameters of quality and safety of the finished product have been revealed. In the study regularities in identification of critical control points have been determined. The algorithm of functioning of the integrated system of the quality management and safety assurance has also been described and key requirements for the development of software allowing the prediction of properties of finished product, as well as the timely correction of the technological process and traceability of manufacturing flows have been defined. Based on the obtained results typical scheme of the integrated system of the quality management and safety assurance based on HACCP principles with the elements of end-to-end traceability and system approach for manufacture of cooked sausage products has been developed. As a result of the studies quantitative criteria for evaluation of performance of the system of the quality management and safety assurance have been developed. A set of guidance documents for the implementation and evaluation of the integrated system based on the HACCP principles in meat processing plants have also been developed. On the basis of the research the effectiveness of application of continuous monitoring of the manufacturing process during the control on the identified critical control points have been revealed. The optimal number of critical control points in relation to the manufacture of cooked sausage products has been substantiated. The main results of the research have been appraised during 2013-2014 under the conditions of seven enterprises of the meat processing industry and have been implemented at JSC «Kyiv meat processing plant».

Keywords: cooked sausage products, HACCP, quality management, safety assurance

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Authors: Olusegun D. Omotoso

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The use of Moringa oleifera seed oil in the prevention and cure of many ailments particularly, neurodegenerative diseases have been on increasing trend in Nigeria. The study was aimed at investigating the ameliorative or reversal effects by the intervention of Moringa oleifera seed oil on the damage to frontal cortex of Wistar rats by cadmium. Twenty-eight Wistar rats of both sexes weighed between 73g-151g were used. The animals were acclimatized and were fed on rat chow and water ad libitum. The rats were randomly divided into four groups A, B, C and D of 7 rats each. Group A served as control which received 2.5mg/kgbw phosphate buffer intra-peritoneally, while group D served as Moringa-treated control and received oral administration of 2.0 mg/kgbw Moringa oleifera oil. Groups B and C were injected intra-peritoneally with 3.5mg/kgbw CdSO₄.8H₂O single dose. Group C received orally administration of 2.0mg/kgbw Moringa oleifera oil. The intervention lasted for four weeks after which the animals were sacrificed by cervical dislocation and the tissues processed histologically. The immuno-histoarchitecture of the frontal cortex was characterized by pyknosis of nuclei as well as activation of astrocytes which was evidence in group B rats, while those animals in group C showed ameliorative effect that were evidence in reduction in the number of pyknotic nuclei and reduction of activated astrocytes as compared with control group A and Moringa-treated group D. It can be deduced that Moringa oleifera seed oil has natural antioxidant constituents that might have ameliorated the immuno-histoarchitectural damage caused by cadmium.

Keywords: cadmium, immuno-histoarchitecture, Moringa oleifera, pyknotic nuclei

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Authors: Ibrahim Rassoul, A. Serir, E-K. Si Ahmed, J. Legrand

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The acronym PEM refers to Proton Exchange Membrane or alternatively Polymer Electrolyte Membrane. Due to its high efficiency, low operating temperature (30–80 °C), and rapid evolution over the past decade, PEMFCs are increasingly emerging as a viable alternative clean power source for automobile and stationary applications. Before PEMFCs can be employed to power automobiles and homes, several key technical challenges must be properly addressed. One technical challenge is elucidating the mechanisms underlying water transport in and removal from PEMFCs. On one hand, sufficient water is needed in the polymer electrolyte membrane or PEM to maintain sufficiently high proton conductivity. On the other hand, too much liquid water present in the cathode can cause “flooding” (that is, pore space is filled with excessive liquid water) and hinder the transport of the oxygen reactant from the gas flow channel (GFC) to the three-phase reaction sites. The experimental transparent fuel cell used in this work was designed to represent actual full scale of fuel cell geometry. According to the operating conditions, a number of flow regimes may appear in the microchannel: droplet flow, blockage water liquid bridge /plug (concave and convex forms), slug/plug flow and film flow. Some of flow patterns are new, while others have been already observed in PEMFC microchannels. An algorithm in MATLAB was developed to automatically determine the flow structure (e.g. slug, droplet, plug, and film) of detected liquid water in the test microchannels and yield information pertaining to the distribution of water among the different flow structures. A video processing algorithm was developed to automatically detect dynamic and static liquid water present in the gas channels and generate relevant quantitative information. The potential benefit of this software allows the user to obtain a more precise and systematic way to obtain measurements from images of small objects. The void fractions are also determined based on images analysis. The aim of this work is to provide a comprehensive characterization of two-phase flow in an operating fuel cell which can be used towards the optimization of water management and informs design guidelines for gas delivery microchannels for fuel cells and its essential in the design and control of diverse applications. The approach will combine numerical modeling with experimental visualization and measurements.

Keywords: polymer electrolyte fuel cell, air-water two phase flow, gas diffusion layer, microchannels, advancing contact angle, receding contact angle, void fraction, surface tension, image processing

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Authors: Rachael Bentley, Callahan Gergen, Brodie Thiede

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Roadways have a significant impact on the environment in so far as they function as barriers to wildlife movement, both through road mortality and through resultant road avoidance. Roads have an im-mense presence worldwide, and it is predicted to increase substantially in the next thirty years. As roadways become even more common, it is important to consider their environmental impact, and to mitigate the negative effects which they have on wildlife and wildlife mobility. In a thorough analysis of several related studies, a common conclusion was that roads cause habitat fragmentation, which can lead split populations to evolve differently, for better or for worse. Though some populations adapted positively to roadways, becoming more resistant to road mortality, and more tolerant to noise and chemical contamination, many others experienced maladaptation, either due to chemical contamination in and around their environment, or because of genetic mutations from inbreeding when their population was fragmented too substantially to support a large enough group for healthy genetic exchange. Large mammals were especially susceptible to maladaptation from inbreed-ing, as they require larger areas to roam and therefore require even more space to sustain a healthy population. Regardless of whether a species evolved positively or negatively as a result of their proximity to a road, animals tended to avoid roads, making the genetic diversity from habitat fragmentation an exceedingly prevalent issue in the larger discussion of road ecology. Additionally, the consideration of solu-tions, such as overpasses and underpasses, is crucial to ensuring the long term survival of many wildlife populations. In studies addressing the effectiveness of overpasses and underpasses, it seemed as though animals adjusted well to these sorts of solutions, but strategic place-ment, as well as proper sizing, proper height, shelter from road noise, and other considerations were important in construction. When an underpass or overpass was well-built and well-shielded from human activity, animals’ usage of the structure increased significantly throughout its first five years, thus reconnecting previously divided populations. Still, these structures are costly and they are often unable to fully address certain issues such as light, noise, and contaminants from vehicles. Therefore, the need for further discussion of new, crea-tive solutions remains paramount. Roads are one of the most consistent and prominent features of today’s landscape, but their environmental impacts are largely overlooked. While roads are useful for connecting people, they divide landscapes and animal habitats. Therefore, further research and investment in possible solutions is necessary to mitigate the negative effects which roads have on wildlife mobility and to pre-vent issues from resultant habitat fragmentation.

Keywords: fences, habitat fragmentation, roadways, wildlife mobility

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Authors: Salaheddine Bendak, Sara S. Alnaqbi

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The seat belt is a vital tool in improving traffic safety conditions and minimising injuries due to traffic accidents. Most developing countries are facing a big problems associated with the human and financial losses due to traffic accidents. One way to minimise these losses is the use of seat belts by passengers both in the front and rear seats of a vehicle; however, at the same time, close to nothing is known about the rates of seat belt utilisation among rear seat passengers in many developing countries. Therefore, there is a need to estimate these rates in order to know the extent of this problem and how people interact with traffic safety measures like seat belts and find demographic characteristics that contribute to wearing or non-wearing of seat belts with the aim of finding solutions to improve wearing rates. In this paper, an observational study was done to gather data on restraints use in motor vehicle rear seats in eight observational stations in a rapidly developing country, the United Arab Emirates (UAE), and estimate a use rate for the whole country. Also, a questionnaire was used in order to study demographic characteristics affecting the wearing of seatbelts in rear seats. Results of the observational study showed that the overall wearing/usage rate was 12.3%, which is considered very low when compared to other countries. Survey results show that single, male, less educated passengers from Arab and South Asian backgrounds use seat belts reportedly less than others. Finally, solutions are put forward to improve this wearing rate based on the results of this study.

Keywords: Seat belts, traffic crashes, United Arab Emirates, rear seats

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Authors: Aung Phyo Kyaw, Kuo Chieh Chao

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Expansive soils are more complicated than normal soils, although the soil itself is not very complicated. When evaluating foundation performance on expansive soil, it is important to consider soil expansion. The primary focus of this study is on hydraulic cement and expansive soil mixtures, and the research aims to identify key parameters for controlling the swell of the expansive soil-hydraulic cement mixture. Treatment depths can be determined using hydraulic cement ratios of 4%, 8%, 12%, and 15% for treating expansive soil. To understand the effect of hydraulic cement percentages on the swelling of expansive soil-hydraulic admixture, performing the consolidation-swell test σ''ᶜˢ is crucial. This investigation primarily focuses on consolidation-swell tests σ''ᶜˢ, although the heave index Cₕ is also needed to determine total heave. The heave index can be measured using the percent swell in the specific inundation stress in both the consolidation-swell test and the constant-volume test swelling pressure. Obtaining the relationship between swelling pressure and σ''ᶜⱽ determined from the "constant volume test" is useful in predicting heave from a single oedometer test. The relationship between σ''ᶜˢ and σ''ᶜⱽ is based on experimental results of expansive soil behavior and facilitates heave prediction for each soil. In this method, the soil property "m" is used as a parameter, and common soil property tests include compaction, particle size distribution, and the Atterberg limit. The Electricity Generating Authority of Thailand (EGAT) provided the soil sample for this study, and all laboratory testing is performed according to American Society for Testing and Materials (ASTM) standards.

Keywords: expansive soil, swelling pressure, total heave, treatment depth

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Authors: Dong Chen, Han Song, Tingting Wei

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Industrial zones have made significant contributions to the economic development of Chinese urban areas for decades. In the background of China's New Normal, numbers of mature industrial zones are stepping into a new stage of inventory development instead of increment development. The aim of this study is to discover new characteristics and problems and corresponding inventory planning guidance of mature industrial zones. A case of Yangzhou Hi-Tech Industrial Development Zone is reported in this study. Based on a historical analysis and data analysis of land-use, it is found that land-use of the zone is near saturation and signs of land updating have begun to appear. It is observed that the zone is facing problems including disorder of land development, low economic productivity and single function. Through the data of economic output, tax contribution, industrial category, industry life cycle and environmental influence, a comprehensive assessment based on two dimensions, economic benefits and industrial matchup, is made upon every parcel in the zone. According to the assessment, the zone is divided into spatial units of the update with specific planning guidance. It comes to a conclusion as four directions of inventory planning guidance in mature industrial zones: moving industries with poor economic benefit and negative environmental influence, adding urban function and new industrial function to the zone, optimizing the function of important space, and restricting the mass layout of the real estate industry to provide space for industrial upgrading.

Keywords: China's new normal, mature industrial zones, land-use, inventory planning

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Authors: Mangala M. Pai, B. V. Murlimanju, Latha V. Prabhu, P. J. Jiji , Vandana Blossom

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Background:To study the morphological parameters of the axis vertebra in anatomical specimens. Methods: The present study was designed to obtain the morphometric data of axis vertebra. The superior and inferior articular facets of the axis were macroscopically observed for their shapes and the different parameters were measured using the digital Vernier caliper. It included 20 dried axis bones, which were obtained from the anatomy laboratory. Results: The morphometric data obtained in the present study are represented in the tables. The side wise comparison of the length and width of the articular facets of the axis vertebra were done. The present study observed that, there is no statistically significant difference observed among the parameters of right and left side articular facets (p>0.05). The superior and inferior articular facets were observed to have variable shapes. The frequencies of different shapes of superior and inferior articular facets are represented in figures. All the shapes of the inferior and superior articular facets were symmetrical over the right and left sides. Among the superior articular facets, the constrictions were absent in 13 cases (65%), 2 (10%) exhibited a single constriction, 3 (15%) had 2 constrictions and 2 (10%) were having 3 constrictions. The constrictions were absent in 11 (55%) of the inferior articular facets, 3 (15%) of them had 1 constriction, 3 (15%) were having 2 constrictions, 2 (10%) exhibited 3 constrictions and 1 (5%) of them had 4 constrictions. The constrictions of the inferior and superior articular facets were symmetrical over the right and left sides. Conclusion: We believe that the present study has provided additional information on the morphometric data of the axis vertebra. The data are important to the neurosurgeons, orthopedic surgeons and radiologists. The preoperative assessment of the axis vertebra may prevent dangerous complications like spinal cord and nerve root compression during the surgical intervention.

Keywords: axis, articular facet, morphology, morphometry

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Authors: Samira Khalaji, , Fenneke Klein Jan, Kay-E. Gottschalk, Eugenia Makrantonaki, Karin Scharffetter-Kochanek

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Biological aging is a multi-dimensional process that takes place over a whole range of scales from the nanoscopic alterations within individual cells, over transformations in tissues and organs and to changes of the whole organism. On the single cell level, aging involves mutation of genes, differences in gene expression levels as well as altered posttranslational modifications of proteins. A variety of proteins is affected, including proteins of the cell cytoskeleton and migration machinery. Previous work quantified the expression of cytoskeleton proteins on the gene and protein levels in senescent and young fibroblasts. Their results show that senescent skin fibroblasts have an upregulated expression of the intermediate filament (IF) protein vimentin in contrast to actin and tubulin, which are downregulated. IFs play an important role in providing mechanical stability of cells. However, the mechanical properties of IFs depending on cellular senescence or age of the donor has not been studied so far. Hence, we employed passive microrheology on primary human dermal fibroblasts from female donors with age of 28 years (young) and 86 years (old) as model of in vivo aging and human normal dermal fibroblast from 11-year old male with CPD 17-35 (young) and CPD 58-59 (senescence) as a model of in vitro replicative senescence. In contrast to the expectations, our primary results show no significant differences in the viscoelastic properties of fibroblasts depending on age of the donor or cellular replicative senescence.

Keywords: aging, cytoskeleton, fibroblast, mechanical properties

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Authors: Claire Stafford, Charles Golden, Daniel Amen, Kristen Willeumier

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The aim of this study is to investigate the effect of the administration of the Conners Continuous Performance Test (CPT-3) on cerebral blood flow (CBF) in adults with ADHD. The data for this study was derived from a large SPECT database. Participants in the ADHD group (n=81, Mage=37.97) were similar to those in the healthy control group (n=8503, Mage=41.86). All participants were assessed for cerebral blood flow levels before and after CPT-3 administration. Both age and gender were considered covariates. Multiple 2-by-2 ANCOVAs with repeated measures were conducted with sphericity assumed. The main effects of CPT-3 administration on CBF levels were significant in the left and right side of the frontal and occipital, and right temporal lobe. The main effects of ADHD diagnosis were significant in all brain areas assessed. The interaction between CPT-3 administration and ADHD diagnosis was significant in the left and right side of the limbic system, basal ganglia, the frontal lobe, and occipital lobe. Post hoc tests with a Bonferroni adjustment revealed that CBF levels increased following CPT-3 administration but less so in the ADHD group. Individuals had higher levels of CBF following the administration of CPT-3. Due to a significant interaction, we can infer that ADHD diagnosis changes the effect of CPT-3 administration on CBF levels. This is consistent with our hypothesis considering that CPT-3 is a test of sustained attention, a common challenge for children with ADHD. The aforementioned interaction was not found to be significant in the parietal lobe. This may be due to the nature of CPT- 3 which does not require an integration of sensory information.

Keywords: SPECT, ADHD, conners continuous performance test, cerebral blood flow

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Authors: Moulay Driss Mellaoui, Abdallah Imjjad, Rachid Boutiddar, Haydar Mohammad-Salim, Nivedita Acharjee, Hassan Bourzi, Souad El Issami, Khalid Abbiche, Hanane Zejli

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We have investigated the underlying molecular processes involved in the [3+2] cycloaddition (32CA) reactions between N-methyl-C-(2-furyl) nitrone and three acetylene derivatives: 4b, 5b, and 6b. For this investigation, we utilized molecular electron density theory (MEDT) and density functional theory (DFT) methods at the B3LYP-D3/6 31G (d) computational level. These 32CA reactions, which exhibit a zwitterionic (zw-type) nature, proceed through a one-step mechanism with activation enthalpies ranging from 8.80 to 14.37 kcal mol−1 in acetonitrile and ethanol solvents. When the nitrone reacts with phenyl methyl propiolate (4b), two regioisomeric pathways lead to the formation of two products: P1,5-4b and P1,4-4b. On the other hand, when the nitrone reacts with dimethyl acetylene dicarboxylate (5b) and acetylene dicarboxylic acid (but-2-ynedioic acid) (6b), it results in the formation of a single product. Through topological analysis, we can categorize the nitrone as a zwitterionic three-atom component (TAC). Furthermore, the analysis of conceptual density functional theory (CDFT) indices classifies the 32CA reactions of the nitrone with 4b, 5b, and 6b as forward electron density flux (FEDF) reactions. The study of bond evolution theory (BET) reveals that the formation of new C-C and C-O covalent bonds does not initiate in the transition states, as the intermediate stages of these reactions display pseudoradical centers of the atoms already involved in bonding.

Keywords: 4-isoxazoline, DFT/B3LYP-D3, regioselectivity, cycloaddition reaction, MEDT, ELF

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Authors: Jeries J. Abou-Hanna

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Several techniques exist for determining stress-intensity factors in linear elastic fracture mechanics analysis. These techniques are based on analytical, numerical, and empirical approaches that have been well documented in literature and engineering handbooks. However, not all techniques share the same merit. In addition to overly-conservative results, the numerical methods that require extensive computational effort, and those requiring copious user parameters hinder practicing engineers from efficiently evaluating stress-intensity factors. This paper investigates the prospects of reducing the complexity and required variables to determine stress-intensity factors through the utilization of the stress gradient and a weighting function. The heart of this work resides in the understanding that fracture emanating from stress concentration locations cannot be explained by a single maximum stress value approach, but requires use of a critical volume in which the crack exists. In order to understand the effectiveness of this technique, this study investigated components of different notch geometry and varying levels of stress gradients. Two forms of weighting functions were employed to determine stress-intensity factors and results were compared to analytical exact methods. The results indicated that the “exponential” weighting function was superior to the “absolute” weighting function. An error band +/- 10% was met for cases ranging from a steep stress gradient in a sharp v-notch to the less severe stress transitions of a large circular notch. The incorporation of the proposed method has shown to be a worthwhile consideration.

Keywords: fracture mechanics, finite element method, stress intensity factor, stress gradient

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Authors: Neyzielle Ronnicque Cadiz

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The Philippine is a hotbed of disasters and is a locus of natural hazards. With an average of 20 typhoons entering the Philippine Area of Responsibility (PAR) each year, seven to eight (7-8) of which makes landfall. The country rather inevitably suffers from climate-related calamities. With this vulnerability to natural hazards, the relevant hazard-related issues that come along with the potential threat and occurrence of a disaster oftentimes garners lesser media attention than when a disaster actually occurred. Post-disaster news and events flood the content of news networks primarily focusing on, but not limited to, the efforts of the national government in resolving post-disaster displacement, and all the more on the community leaders’ incompetence in disaster mitigation-- even though the University of the Philippines’ NOAH Center work hand in hand with different stakeholders for disaster mitigation communication efforts. Disaster risk communication is actually a perennial dilemma. There are so many efforts to reach the grassroots level but emergency and disaster preparedness messages inevitably fall short.. The Philippines is very vulnerable to hazards risk and disasters but social media posts and communication efforts mostly go unnoticed, if not argued upon. This study illustrates the outcomes of a research focusing on the print, broadcast, and social media’s role on disaster communication involving the natural catastrophic events that took place in the Philippines from 2009 to present. Considering the country’s state of development, this study looks on the rapid and reliable communication between the government, and the relief/rescue workers in the affected regions; and how the media portrays these efforts effectively. Learning from the disasters that have occurred in the Philippines over the past decade, effective communication can ensure that any efforts to prepare and respond to disasters can make a significant difference. It can potentially either break or save lives. Recognizing the role of communications is not only in improving the coordination of vital services for post disaster; organizations gave priority in reexamining disaster preparedness mechanisms through the Communication with Communities (CwC) programs. This study, however, looks at the CwC efforts of the Philippine media platforms. CwC, if properly utilized by the media, is an essential tool in ensuring accountability and transparency which require effective exchange of information between disasters and survivors and responders. However, in this study, it shows that the perennial dilemma of the Philippine media is that the Disaster Risk Reduction and Management (DRRM) efforts of the country lie in the clouded judgment of political aims. This kind of habit is a multiplier of the country’s risk and insecurity. Sometimes the efforts in urging the public to take action seem useless because the challenge lies on how to achieve social, economic, and political unity using the tri-media platform.

Keywords: Philippines at risk, pre/post disaster communication, tri-media platform, UP NOAH

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Authors: Renata Checiches, Thierry Coche, Nicolas F. Delahaye, Albert Linder, Fernando Ulloa Montoya, Olivier Gruselle, Karen Langfeld, An de Creus, Bart Spiessens, Vincent G. Brichard, Jamila Louahed, Frédéric F. Lehmann

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Background: The RNA-expression levels of cancer-testis antigens MAGE A3 and PRAME were determined in resected tissue from patients with primary non-small-cell lung cancer (NSCLC) and related to clinical outcome. EGFR, KRAS and BRAF mutation status was determined in a subset to investigate associations with MAGE A3 and PRAME expression. Methods: We conducted a single-centre, uncontrolled, retrospective study of 1260 tissue-bank samples from stage IA-III resected NSCLC. The prognostic value of antigen expression (qRT-PCR) was determined by hazard-ratio and Kaplan-Meier curves. Results: Thirty-seven percent (314/844) of tumours expressed MAGE-A3, 66% (723/1092) expressed PRAME and 31% (239/839) expressed both. Respective frequencies in squamous-cell tumours and adenocarcinomas were 43%/30% for MAGE A3 and 80%/44% for PRAME. No correlation with stage, tumour size or patient age was found. Overall, no prognostic value was identified for either antigen. A trend to poorer overall survival was associated with MAGE-A3 in stage IIIB and with PRAME in stage IB. EGFR and KRAS mutations were found in 10.1% (28/311) and 33.8% (97/311) of tumours, respectively. EGFR (but not KRAS) mutation status was negatively associated with PRAME expression. Conclusion: No clear prognostic value for either PRAME or MAGE A3 was observed in the overall population, although some observed trends may warrant further investigation.

Keywords: MAGE A3, PRAME, cancer-testis gene, NSCLC, survival, EGFR

Procedia PDF Downloads 382

Authors: Georgi Vendramin, Aurea Lúcia, Yamamoto, Carlos Itsuo, Souza Melegari, N. Samuel

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This article describes the development of a model that uses a method where openings are represented by single glass and double glass. The model is based on a healthy balance equations purely theoretical and empirical data. Simplified equations are derived through a synthesis of the measured data obtained from meteorological stations. The implementation of the model in a design tool integrated buildings is discussed in this article, to better punctuate the requirements of comfort and energy efficiency in architecture and engineering. Sustainability, energy efficiency, and the integration of alternative energy systems and concepts are beginning to be incorporated into designs for new buildings and renovations to existing buildings. Few means have existed to effectively validate the potential performance benefits of the design concepts. It was used a method of degree-days for an assessment of the energy performance of a building showed that the design of the architectural design should always be considered the materials used and the size of the openings. The energy performance was obtained through the model, considering the location of the building Central Park Shopping Mall, in the city of Cascavel - PR. Obtained climatic data of these locations and in a second step, it was obtained the coefficient of total heat loss in the building pre-established so evaluating the thermal comfort and energy performance. This means that the more openings in buildings in Cascavel – PR, installed to the east side, they may be higher because the glass added to the geometry of architectural spaces will cause the environment conserve energy.

Keywords: sustainable design, energy modeling, design validation, degree-days methods

Procedia PDF Downloads 419

Authors: Moaine Jebara, Lionel Boillereaux, Sofiane Belhabib, Michel Havet, Alain Sarda, Pierre Mousseau, Rémi Deterre

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Energy consumption efficiency is a major concern for the material processing industry such as thermoforming process and molding. Indeed, these systems should deliver the right amount of energy at the right time to the processed material. Recent technical development, as well as the particularities of the heating system dynamics, made the Model Predictive Control (MPC) one of the best candidates for thermal control of several production processes like molding and composite thermoforming to name a few. The main principle of this technique is to use a dynamic model of the process inside the controller in real time in order to anticipate the future behavior of the process which allows the current timeslot to be optimized while taking future timeslots into account. This study presents a procedure based on a predictive control that brings balance between optimality, simplicity, and flexibility of its implementation. The development of this approach is progressive starting from the case of a single zone before its extension to the multizone and/or multisource case, taking thus into account the thermal couplings between the adjacent zones. After a quadratic formulation of the MPC criterion to ensure the thermal control, the linear expression is retained in order to reduce calculation time thanks to the use of the ARMAX linear decomposition methods. The effectiveness of this approach is illustrated by experiment and simulation.

Keywords: energy efficiency, linear decomposition methods, model predictive control, mold heating systems

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Authors: Merve Kadioğlu, Nevin H. Şahin

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Purpose: This research is organized to determine the influence of the web-based learning program. The program has been developed to gain information about normal delivery skill that is one of the topics of nursing students who take the woman health and illness. Material and Methods: The methodology of this study was applied as pre-test post-test single-group quasi-experimental. The pilot study consisted of 28 nursing student study groups who agreed to participate in the study. The findings were gathered via web-based technologies: student information form, information evaluation tests, Web Based Training Material Evaluation Scale and web-based learning environment feedback form. In the analysis of the data, the percentage, frequency and Wilcoxon Signed Ranks Test were used. The Web Based Instruction Program was developed in the light of full learning model, Mayer's research-based multimedia development principles and Gagne's Instructional Activities Model. Findings: The average scores of it was determined in accordance with the web-based educational material evaluation scale: ‘Instructional Suitability’ 4.45, ‘Suitability to Educational Program’ 4.48, ‘Visual Adequacy’ 4.53, ‘Programming Eligibility / Technical Adequacy’ 4.00. Also, the participants mentioned that the program is successful and useful. A significant difference was found between the pre-test and post-test results of the seven modules (p < 0.05). Results: According to pilot study data, the program was rated ‘very good’ by the study group. It was also found to be effective in increasing knowledge about normal labor.

Keywords: normal delivery, web-based learning, nursing students, e-learning

Procedia PDF Downloads 178

Authors: Farouk Metiri, Halim Zeghdoudi, Mohamed Riad Remita

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Credibility theory is an experience rating technique in actuarial science which can be seen as one of quantitative tools that allows the insurers to perform experience rating, that is, to adjust future premiums based on past experiences. It is used usually in automobile insurance, worker's compensation premium, and IBNR (incurred but not reported claims to the insurer) where credibility theory can be used to estimate the claim size amount. In this study, we focused on a popular tool in credibility theory which is the Bayesian premium estimator, considering Lindley distribution as a claim distribution. We derive this estimator under entropy loss which is asymmetric and squared error loss which is a symmetric loss function with informative and non-informative priors. In a purely Bayesian setting, the prior distribution represents the insurer’s prior belief about the insured’s risk level after collection of the insured’s data at the end of the period. However, the explicit form of the Bayesian premium in the case when the prior is not a member of the exponential family could be quite difficult to obtain as it involves a number of integrations which are not analytically solvable. The paper finds a solution to this problem by deriving this estimator using numerical approximation (Lindley approximation) which is one of the suitable approximation methods for solving such problems, it approaches the ratio of the integrals as a whole and produces a single numerical result. Simulation study using Monte Carlo method is then performed to evaluate this estimator and mean squared error technique is made to compare the Bayesian premium estimator under the above loss functions.

Keywords: bayesian estimator, credibility theory, entropy loss, monte carlo simulation

Procedia PDF Downloads 334

Authors: E. M. Vieira, C. S. Vieira, L. P. Bonifácio, L. M. de Oliveira Ciabati, A. C. A. Franzon, F. S. Zaratini, J. A. C. Sanchez, M. S. Andrade, J. P. Dias de Souza

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The quality of prenatal care is key to reduce maternal morbidity and mortality. Communication between the health service and users can stimulate prevention and care. M-health has been an important and low cost strategy to health education. The PRENACEL programme (prenatal in the cell phone) was developed. It consists of a programme of information via SMS from the 20^th week of pregnancy up to 12^th week after delivery. Messages were about prenatal care, birth, contraception and breastfeeding. Communication of the pregnant woman asking questions about their health was possible. The objective of this study was to evaluate the implementation of PRENACEL as a useful complement to the standard prenatal care. Twenty health clinics were selected and randomized by cluster, 10 as the intervention group and 10 as the control group. In the intervention group, women and their partner were invited to participate. The control group received the standard prenatal care. All women were interviewed in the immediate post-partum and in the 12^th and 24^th week post-partum. Most women were married, had more than 8 years of schooling and visit the clinic more than 6 times during prenatal care. The intervention group presented lowest percentage of higher economic participants (5.6%), less single mothers and no drug user. It also presented more prenatal care visits than the control group and it was less likely to present Severe Acute Maternal Mortality when compared to control group as well as higher percentage of partners (75.4%) was present at the birth compared to control group. Although the study is still being carried out, preliminary data are showing positive results of the compliance of women to prenatal care.

Keywords: cellphone, health technology, prenatal care, prevention

Procedia PDF Downloads 389

Authors: Premjit K. Sanjram, Gagan Jakhotiya, Apoorv Goyal, Shanu Shukla

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In psychological research, laboratory experiments often face the trade-off issue between experimental control and mundane realism. With the advent of Immersive Virtual Environment Technology (IVET), this issue seems to be at bay. However there is a growing challenge within the IVET itself to design and develop system or software that captures the psychological phenomenon of everyday lives. One such phenomena that is of growing interest is ‘media-multitasking’ To aid laboratory researches in media-multitasking this paper introduces Query Task Modulator (QTM), a computerized experimentation system to study media-multitasking behavior in a controlled laboratory environment. The system provides a computerized platform in conducting an experiment for experimenters to study media-multitasking in which participants will be involved in a query task. The system has Instant Messaging, E-mail, and Voice Call features. The answers to queries are provided on the left hand side information panel where participants have to search for it and feed the information in the respective communication media blocks as fast as possible. On the whole the system will collect multitasking behavioral data. To analyze performance there is a separate output table that records the reaction times and responses of the participants individually. Information panel and all the media blocks will appear on a single window in order to ensure multi-modality feature in media-multitasking and equal emphasis on all the tasks (thus avoiding prioritization to a particular task). The paper discusses the development of QTM in the light of current techniques of studying media-multitasking.

Keywords: experimentation system, human performance, media-multitasking, query-task

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Authors: Sanaz Ahmadzadeh Siyahrood, Arghavan Ebrahimi, Mohammadjavad Mahdavinejad

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Islamic culture was accountable for a plethora of development in astronomy and science in the medieval term, and in geometry likewise. Geometric patterns are reputable in a considerable number of cultures, but in the Islamic culture the patterns have specific features that connect the Islamic faith to mathematics. In Islamic art, three fundamental shapes are generated from the circle shape: triangle, square and hexagon. Originating from their quiddity, each of these geometric shapes has its own specific structure. Even though the geometric patterns were generated from such simple forms as the circle and the square, they can be combined, duplicated, interlaced, and arranged in intricate combinations. So in order to explain geometrical interaction principles between square and equal triangle, in the first definition step, all types of their linear forces individually and in the second step, between them, would be illustrated. In this analysis, some angles will be created from intersection of their directions. All angles are categorized to some groups and the mathematical expressions among them are analyzed. Since the most geometric patterns in Islamic art and architecture are based on the repetition of a single motif, the evaluation results which are obtained from a small portion, is attributable to a large-scale domain while the development of infinitely repeating patterns can represent the unchanging laws. Geometric ornamentation in Islamic art offers the possibility of infinite growth and can accommodate the incorporation of other types of architectural layout as well, so the logic and mathematical relationships which have been obtained from this analysis are applicable in designing some architecture layers and developing the plan design.

Keywords: angle, equal triangle, square, structural hierarchy

Procedia PDF Downloads 195

Authors: Emma S. Bowers

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Perturbations in global environments and temperatures have heightened the urgency of creating cost-efficient, energy-neutral building techniques. Structural responses to this thermal crisis have included designs (including those of the building standard PassivHaus) with airtightness, window placement, insulation, solar orientation, shading, and heat-exchange ventilators as potential solutions or interventions. Limitations in the predictability of the circulation of cooled air through the ambient temperature gradients throughout a structure are one of the major obstacles facing these enhanced building methods. A diverse range of air-cooling devices utilizing varying technologies is implemented around the world. Many of them worsen the problem of climate change by consuming energy. Using natural ventilation principles of air buoyancy and density to circulate fresh air throughout a building with no energy input can combat these obstacles. A unique prototype of an energy-neutral air-circulation system was constructed in order to investigate potential temperature and pressure gradients related to the stack effect (updraft of air through a building due to changes in air pressure). The stack effect principle maintains that since warmer air rises, it will leave an area of low pressure that cooler air will rush in to fill. The result is that warmer air will be expelled from the top of the building as cooler air is directed through the bottom, creating an updraft. Stack effect can be amplified by cooling the air near the bottom of a building and heating the air near the top. Using readily available, mostly recyclable or biodegradable materials, an insulated building module was constructed. A tri-part construction model was utilized: a subterranean earth-tube heat exchanger constructed of PVC pipe and placed in a horizontally oriented trench, an insulated, airtight cube aboveground to represent a building, and a solar chimney (painted black to increase heat in the out-going air). Pressure and temperature sensors were placed at four different heights within the module as well as outside, and data was collected for a period of 21 days. The air pressures and temperatures over the course of the experiment were compared and averaged. The promise of this design is that it represents a novel approach which directly addresses the obstacles of air flow and expense, using the physical principle of stack effect to draw a continuous supply of fresh air through the structure, using low-cost and readily available materials (and zero manufactured energy). This design serves as a model for novel approaches to creating temperature controlled buildings using zero energy and opens the door for future research into the effects of increasing module scale, increasing length and depth of the earth tube, and shading the building. (Model can be provided).

Keywords: air circulation, PassivHaus, stack effect, thermal gradient

Procedia PDF Downloads 154

Authors: Hossein Tavallali, Mohammad Ali Karimi, Gohar Deilamy-Rad

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The proposed method for speciation, preconcentration and determination of Fe(II) and Fe(III) in pharmaceutical products was developed using of alumina-coated magnetite nanoparticles (Fe₃O₄/Al₂O₃ NPs) as solid phase extraction (SPE) sorbent in magnetic mixed hemimicell solid phase extraction (MMHSPE) technique followed by flame atomic absorption spectrometry analysis. The procedure is based on complexation of Fe(II) with 1, 10-phenanthroline (OP) as complexing reagent for Fe(II) that immobilized on the modified Fe₃O₄/Al₂O₃ NPs. The extraction and concentration process for pharmaceutical sample was carried out in a single step by mixing the extraction solvent, magnetic adsorbents under ultrasonic action. Then, the adsorbents were isolated from the complicated matrix easily with an external magnetic field. Fe(III) ions determined after facility reduced to Fe(II) by added a proper reduction agent to sample solutions. Compared with traditional methods, the MMHSPE method simplified the operation procedure and reduced the analysis time. Various influencing parameters on the speciation and preconcentration of trace iron, such as pH, sample volume, amount of sorbent, type and concentration of eluent, were studied. Under the optimized operating conditions, the preconcentration factor of the modified nano magnetite for Fe(II) 167 sample was obtained. The detection limits and linear range of this method for iron were 1.0 and 9.0 - 175 ng.mL⁻¹, respectively. Also the relative standard deviation for five replicate determinations of 30.00 ng.mL^-1 Fe²⁺ was 2.3%.

Keywords: Alumina-Coated magnetite nanoparticles, Magnetic Mixed Hemimicell Solid-Phase Extraction, Fe(ΙΙ) and Fe(ΙΙΙ), pharmaceutical sample

Procedia PDF Downloads 292