Search results for: stress measurement

Authors: Alexa Rakoski, Yun Suk Eo, Cagliyan Kurdak, Priscila F. S. Rosa, Zachary Fisk, Monica Ciomaga Hatnean, Geetha Balakrishnan, Boyoun Kang, Myungsuk Song, Byungki Cho

Abstract:

Samarium hexaboride (SmB6) is a strongly correlated mixed valence material and Kondo insulator. In the resistance-temperature curve, SmB6 exhibits activated behavior from 4-40 K after the Kondo gap forms. However, below 4 K, the resistivity is temperature independent or weakly temperature dependent due to the appearance of a topologically protected surface state. Current research suggests that the surface of SmB6 is conductive while the bulk is truly insulating, different from conventional 3D TIs (Topological Insulators) like Bi₂Se₃ which are plagued by bulk conduction due to impurities. To better understand why the bulk of SmB6 is so different from conventional TIs, this study employed a new method, called inverted resistance, to explore the lowest temperatures, as well as standard Hall measurements for the rest of the temperature range. In the inverted resistance method, current flows from an inner contact to an outer ring, and voltage is measured outside of this outer ring. This geometry confines the surface current and allows for measurement of the bulk resistivity even when the conductive surface dominates transport (below 4 K). The results confirm that the bulk of SmB6 is truly insulating down to 2 K. Hall measurements on a number of samples show consistent bulk behavior from 4-40 K, but widely varying behavior among samples above 40 K. This is attributed to a combination of the growth process and purity of the starting material, and the relationship between the high and low temperature behaviors is still being explored.

Keywords: bulk transport, Hall effect, inverted resistance, Kondo insulator, samarium hexaboride, topological insulator

Procedia PDF Downloads 160

Authors: Louis N. Y. Wong

Abstract:

En-echelon fractures are commonly found in rocks, which appear as a special set of regularly oriented and spaced fractures. By using both experimental and numerical approaches, this study investigates the interaction among them, and how this interaction finally contributes to the development of a shear rupture (fault), especially in brittle natural rocks. Firstly, uniaxial compression tests are conducted on marble specimens containing en-echelon flaws. The latter is cut by using the water abrasive jet into the rock specimens. The fracturing processes of these specimens leading to the formation of a fault are observed in detail by the use of a high speed camera. The influences of the flaw geometry on the production of tensile cracks and shear cracks, which in turn dictate the coalescence patterns of the entire set of en-echelon flaws are comprehensively studied. Secondly, a numerical study based on a recently developed contact model, flat-joint contact model using the discrete element method (DEM) is carried out to model the present laboratory experiments. The numerical results provide a quantitative assessment of the interaction of en-echelon flaws. Particularly, the evolution of the stress field, as well as the characteristics of new crack initiation, propagation and coalescence associated with the generation of an eventual shear rupture are studied in detail. The numerical results are found to agree well with the experimental results obtained in both microscopic and macroscopic observations.

Keywords: discrete element method, en-echelon flaws, fault, marble

Procedia PDF Downloads 255

Authors: Tayyaba Bibi, Jenny Ronan, Robert Hernan, Kathleen O’Rourke, Brendan McHugh, Evin McGovern, Michelle Giltrap, Gordon Chambers, James Wilson

Abstract:

Sediment contamination is a major source of ecosystem stress and has received significant attention from the scientific community. Both the Water Framework Directive (WFD) and Marine Strategy Framework Directive (MSFD) require a robust set of tools for biological and chemical monitoring. For the MSFD in particular, causal links between contaminant and effects need to be assessed. Appropriate assessment tools are required in order to make an accurate evaluation. In this study, a range of recommended sediment bioassays and chemical measurements are assessed in a number of potentially impacted and lowly impacted locations around Ireland. Previously, assessment indices have been developed on individual compartments, i.e. contaminant levels or biomarker/bioassay responses. A number of assessment indices are applied to chemical and ecotoxicological data from the Seachange project (Project code) and compared including the metal pollution index (MPI), pollution load index (PLI) and Chapman index for chemistry as well as integrated biomarker response (IBR). The benefits and drawbacks of the use of indices and aggregation techniques are discussed. In addition to this, modelling of raw data is investigated to analyse links between contaminant and effects.

Keywords: bioassays, contamination indices, ecotoxicity, marine environment, sediments

Procedia PDF Downloads 228

Authors: Seung-Min Yang, Seong-Han Park, Sang-Hoon Lee, Seung-Wan Yoo, Chan-Soo Kim, Nong-Moon Hwang

Abstract:

The theory of charged nanoparticles suggested that in many Chemical Vapour Depositions (CVD) processes, Charged Nanoparticles (CNPs) are generated in the gas-phase and become a building block of thin films and nanowires. Recently, the nanoparticle-based crystallization has become a big issue since the growth of nanorods or crystals by the building block of nanoparticles was directly observed by transmission electron microscopy observations in the liquid cell. In an effort to confirm charged gas-phase nuclei, that might be generated under conventional processing conditions of thin films and nanowires during CVD, we performed an in-situ measurement using differential mobility analyser and particle beam mass spectrometer. The size distribution and number density of CNPs were affected by process parameters such as precursor flow rate and working temperature. It was shown that many films and nanostructures, which have been believed to grow by individual atoms or molecules, actually grow by the building blocks of such charged nuclei. The electrostatic interaction between CNPs and the growing surface induces the self-assembly into films and nanowires. In addition, the charge-enhanced atomic diffusion makes CNPs liquid-like quasi solid. As a result, CNPs tend to land epitaxial on the growing surface, which results in the growth of single crystalline nanowires with a smooth surface.

Keywords: chemical vapour deposition, charged nanoparticle, electrostatic force, nanostructure evolution, differential mobility analyser, particle beam mass spectrometer

Procedia PDF Downloads 452

Authors: Yunjia Wang, Zhihong Zhao, Erxiang Song

Abstract:

Rockfills are widely used in civil engineering, such as dams, railways, and airport foundations in mountain areas. A significant long-term post-construction settlement may affect the serviceability or even the safety of rockfill infrastructures. The creep behavior of rockfills is influenced by a number of factors, such as particle size, strength and shape, water condition and stress level. However, the effect of particle shape on rockfill creep still remains poorly understood, which deserves a careful investigation. Particle-based discrete element method (DEM) was used to simulate the creep behavior of rockfills under different boundary conditions. Both angular and rounded particles were considered in this numerical study, in order to investigate the influence of particle shape. The preliminary results showed that angular particles experience more breakages and larger creep strains under one-dimensional compression than rounded particles. On the contrary, larger creep strains were observed in he rounded specimens in the direct shear test. The mechanism responsible for this difference is that the possibility of the existence of key particle in rounded particles is higher than that in angular particles. The above simulations demonstrate that the influence of particle shape on the creep behavior of rockfills can be simulated by DEM properly. The method of DEM simulation may facilitate our understanding of deformation properties of rockfill materials.

Keywords: rockfills, creep behavior, particle crushing, discrete element method, boundary conditions

Procedia PDF Downloads 313

Authors: Henrique Fernandes, Sofia Catalucci, Richard Leach, Kapil Sugand

Abstract:

Background: Holograms are 3D images formed by the interference of light beams from a laser or other coherent light source. Pepper’s ghost is a form of hologram conceptualised in the 18th century. This Holographic visualisation with metrology measuring techniques by displaying measurements taken in real-time in holographic form can assist in research and education. New structural designs such as the Plexiglass Stand and the Hologram Box can optimise the holographic experience. Method: The equipment used included: (i) Zeiss’s ATOS Core 300 optical coordinate measuring instrument that scanned real-world objects; (ii) Cloud Compare, open-source software used for point cloud processing; and (iii) Hologram Box, designed and manufactured during this research to provide the blackout environment needed to display 3D point clouds in real-time measurements in holographic format, in addition to a portability aspect to holograms. The equipment was tailored to realise the goal of displaying measurements in an innovative technique and to improve on conventional methods. Three test scans were completed before doing a holographic conversion. Results: The outcome was a precise recreation of the original object in the holographic form presented with dense point clouds and surface density features in a colour map. Conclusion: This work establishes a way to visualise data in a point cloud system. To our understanding, this is a work that has never been attempted. This achievement provides an advancement in holographic visualisation. The Hologram Box could be used as a feedback tool for measurement quality control and verification in future smart factories.

Keywords: holography, 3D scans, hologram box, metrology, point cloud

Procedia PDF Downloads 89

Authors: Horesh Reinman Netta

Abstract:

Objectives: To examine the relationship between stressful life events and recurrent major depressive disorders Methods: Three groups of 50 subjects were assessed. One group had a recurrent major depressive disorder with melancholic features; the second group met the criteria for borderline personality disorder, and the third consisted of healthy controls. The Structured Clinical Interview for AXIS I DSM-IV Disorders sand the Structured Clinical Interview for AXIS II DSM-IV Disorders were used for diagnosis. The Israel Psychiatric Epidemiology Research Interview (IPERI) Life Event Scale and the Coddington Life Events Schedule (CLES) were used to measure life events which were confirmed with a confirmatory semi-structured interview. The Beck Depression Inventory and the Satisfaction from Life scales were also administered. Results : The total number of loss-related events in childhood and in the year preceding the first episode was significantly higher in the affective disorder group than in the two control groups. Total number of LE, uncontrolled and independent events were also more common in the depressed patients in the year preceding the first episode. No category of SLE was differentiated among any of the three groups during any period of time following the first depressive episode. Conclusions: SLE play an important role in the onset of affective disorders. There appear to be specific kinds of SLE occurring in childhood and in the year preceding a first episode that have particular significance. SLE may have a lesser role in the maintenance of this illness.

Keywords: modd dosorders, recurrent depression, stress, life events

Procedia PDF Downloads 108

Authors: Sajida Saqira, Anthony Chariton, Grant C. Hose

Abstract:

The Anthropocene has seen dramatic environmental changes which are affecting every ecosystem on earth. Freshwater ecosystems are particularly vulnerable as they are at risk from the many activities that go on and contaminants that are released in catchments. They are thus subject to many stressors simultaneously. Freshwater ecosystems respond to stress at all levels of biological organization, from subcellular to community structure and ecosystem functioning. The aim of this study was to examine the resistance and resilience of freshwater ecosystems to multiple stressors. Here we explored the individual and combined effects of copper as a chemical stressor and common carp (Cyprinus carpio) as a biological stressor on the health, functioning, and recovery of outdoor experimental pond ecosystems in a long-term, controlled, factorial experiment. Primary productivity, decomposition, and water and sediment quality were analysed at regular intervals for one year to understand the health and functioning of the ecosystems. Changes to benthic biota were quantified using DNA-based and traditional microscopy-based counts of invertebrates. Carp were added to the ponds to copper contaminated sediments (with controls) to explore the combined effects of copper and carp and removed after six months to explore the resilience and recovery of the system. The outcomes of this study will advance our understanding of the impacts of multiple stressors on freshwater ecosystems, and the resilience of these systems to copper and C. carpio, which are both globally significant stressors in freshwater systems.

Keywords: carp, copper, ecosystem health, freshwater ecosystem, multiple stressors

Procedia PDF Downloads 122

Authors: J. Singh, Swati Dubey, R. P. Singh

Abstract:

Microalgal strains can accumulate greatly enhanced levels of lipids under nitrogen-deficient condition, making these as one of the most promising sustainable sources for biofuel production. High-grade biofuel production from microalgal biomass could be facilitated by analysing the lipid content of the microalgae and enumerating its dynamics under varying nutrient conditions. In the present study, a detailed investigation of changes in lipid composition in Chlorella species and Scenedesmus abundans in response to nitrogen limited condition was performed to provide novel mechanistic insights into the lipidome during stress conditions. The mass spectroscopic approaches mainly LC-MS and GC-MS were employed for lipidomic profiling in both the microalgal strains. The analyses of lipid profiling using LC-MS revealed distinct forms of lipids mainly phospho- and glycolipids, including betaine lipids, and various other forms of lipids in both the microalgal strains. As detected, an overall decrease in polar lipids was observed. However, GC-MS analyses had revealed that the synthesis of the storage lipid i.e. triacylglycerol (TAG) was substantially stimulated in both the strains under nitrogen limited conditions. The changes observed in the overall fatty acid profile were primarily due to the decrease in proportion of polar lipids to TAGs. This study had enabled in analysing a detailed and orchestrated form of lipidomes in two different microalgal strains having potential for biodiesel production.

Keywords: biofuel, GC-MS, LC-MS, lipid, microalgae

Procedia PDF Downloads 370

Authors: Hossam E. Emam

Abstract:

The functional textiles development history in the military field could be ascribed as a uniquely interesting research topic. Soldiers are like a high-performance athletes, where monitoring their physical and physiological capabilities is a vital requirement. Functional clothes represent a “second skin” that has a close, “intimate” relationship with the human body. For the application of textiles in military purposes, which is normally required in difficult weather and environmental conditions, several functions are required. The requirements for designing functional military textiles for soldier's protection can be categorized into three categories; i) battle field (protection from chemical warfare agents, flames, and thermal radiation), ii) environmental (water proof, air permeable, UV-protection, antibacterial), iii) physiological (minimize heat stress, low weight, insulative, durability). All of these requirements are important, but the means to fulfill these requirements are not simple and straight forward. Additionally, the combination of more than one function is reported to be very expensive and requires many complicated steps, and the final product is found to be low durability. Not only do all of these requirements are overlapping, but they are also contradicting each other at various levels. Thus, we plan to produce multi-functional textiles (e.g., anti-microbial, UV-protection, fire retardant, photoluminescent) to be applied in military clothes. The current project aims to use quite a simple and applicable technique through the modification of textiles with different coordination polymers and functionalized coordination polymers.

Keywords: functional textiles, military clothes, coordination polymers, antimicrobial, fire retardant, photolumenscent

Procedia PDF Downloads 180

Authors: Vladimir Kulyukin, Tanwir Zaman, Sarat Kiran Andhavarapu

Abstract:

Research on nutrition label use identifies four factors that impede comprehension and retention of nutrition information by consumers: label’s location on the package, presentation of information within the label, label’s surface size, and surrounding visual clutter. In this paper, a system is presented that makes nutrition label use more effective for nutrition information comprehension and retention. The system’s front end is a smartphone application. The system’s back end is a four node Linux cluster for image recognition and data storage. Image frames captured on the smartphone are sent to the back end for skewed or aligned barcode recognition. When barcodes are recognized, corresponding nutrition labels are retrieved from a cloud database and presented to the user on the smartphone’s touchscreen. Each displayed nutrition label is positioned centrally on the touchscreen with no surrounding visual clutter. Wikipedia links to important nutrition terms are embedded to improve comprehension and retention of nutrition information. Standard touch gestures (e.g., zoom in/out) available on mainstream smartphones are used to manipulate the label’s surface size. The nutrition label database currently includes 200,000 nutrition labels compiled from public web sites by a custom crawler. Stress test experiments with the node cluster are presented. Implications for proactive nutrition management and food policy are discussed.

Keywords: mobile computing, cloud computing, nutrition label use, nutrition management, barcode scanning

Procedia PDF Downloads 373

Authors: Ibrahim Sengor, Sumeyye Cesur, Ilyas Kartal, Faik Nuzhet Oktar, Nazmi Ekren, Ahmet Talat Inan, Oguzhan Gunduz

Abstract:

In recent years, many researchers focused on nano-size fiber production. Nanofibers have been studied due to their different and superior physical, chemical and mechanical properties. Poly (lactic acid) (PLA), is a type of biodegradable thermoplastic polyester derived from renewable sources used in biomedical owing to its biocompatibility and biodegradability. In addition, zinc oxide is an antibacterial material and hazelnut shell powder is a filling material. In this study, nanofibers were obtained by adding of different ratio Zinc oxide, (ZnO) and hazelnut shell powder at different concentration into Poly (lactic acid) (PLA) by using electrospinning method which is the most common method to obtain nanofibers. After dissolving the granulated polylactic acids in % 1,% 2,% 3 and% 4 with chloroform solvent, they are homogenized by adding tween and hazelnut shell powder at different ratios and then by electrospinning, nanofibers are obtained. Scanning electron microscope (SEM), Fourier transform infrared spectroscopy (FTIR), Differential scanning calorimeter (DSC) and physical analysis such as density, electrical conductivity, surface tension, viscosity measurement and antimicrobial test were carried out after production process. The resulting structures of the nanofiber possess antimicrobial and antiseptic properties, which are attractive for biomedical applications. The resulting structures of the nanofiber possess antimicrobial, non toxic, self-cleaning and rigid properties, which are attractive for biomedical applications.

Keywords: electrospinning, hazelnut shell powder, nanofibers, poly (lactic acid), zinc oxide

Procedia PDF Downloads 166

Authors: Anat Yaron Antar, Tomer Einat

Abstract:

This study explores the effects of the imprisonment of women together with females with mental disorders on the well-being of the former both during imprisonment and after their release from prison. Based on in-depth interviews with 22 women ex-prisoners who had been imprisoned for a period of at least two years in the single Israeli female correctional facility, Neve Tirza Prison, and released one to three months before the initiation of the study to a community-based agency managed by the Israeli Prisoner Rehabilitation Authority, and based on a qualitative, constructive strategy. We found that: (i) mentally ill prisoners’ conduct creates severe feelings of stress and discomfort among many of the prisoners without a mental disorder prisoners; (ii) The intimate and often long-term encounters with prisoners with a mental illness lead to increased feelings of distress, helplessness, fear, and frustration among many of the women prisoners; (iii) the damaging encounters between women prisoners and mentally-ill prisoners harmed the reintegration of the formers into society after release, and (iv) The women ex-prisoners lacked the basic mental, cognitive, and social tools necessary for dealing with female inmates with a mental illness and had received no psychological or emotional support from the prison personnel. Consequently, they suffered – and still suffer – from traumatic and upsetting memories Our findings led us to conclude that women prisoners should be imprisoned separately from female prisoners with mental disorders or be offered a wide range of psychological and emotional coping tools as well as various rehabilitative treatment programs.

Keywords: women, prisoners, mentally ill, health

Procedia PDF Downloads 127

Authors: Subodh Nath Patel, Raja Raman, Mananshi Adhikary, Jitendra Mathur, Sandip Bhattacharyya

Abstract:

The composition adjustment by sealed argon bubbling–oxygen blowing (CAS-OB) process is a process designed for adjusting steel composition and temperature during secondary metallurgy. One of the equipment in the said process is a snorkel or bell, fixed to a movable bracket. Snorkel serves the purpose of feeding ferroalloys into the liquid metal simultaneously removing gases to the gas cleaning system through its port at its top. The bell-shaped snorkel consists of two parts. The upper part has an inside liner, and the lower part is lined on both side with high-alumina castable reinforced with 2% stainless steel needles. Both the parts are coupled with a flange bolt system. These flanges were found to get buckled during operation, and the gap was generating between them. This problem was chronic since its. It was expected to give a life of 80 heats, but it was failing within 45-50 heats. After every 25-30 heats, it had to be repaired by changing and/or tightening its nuts and bolts. Visual observation, microstructural analysis through optical microscopes and SEM, hardness measurement and thermal strain calculation were carried out to find out the root cause of this problem. The calculated thermal strain was compared with actual thermal strain; comparison of the two revealed that thermal strain was responsible for buckling. Finite element analysis (FEA) was carried out to reaffirm the effect temperature on the flanges. FEA was also used in the modification in the design of snorkel flange to accommodate thermal strain. Thermal insulation was also recommended which increased its life from 45 heats to 65 heats, impacting business process positively.

Keywords: CAS OB process, finite element analysis, snorkel, thermal strain

Procedia PDF Downloads 137

Authors: Dalia O. Saleha, Gehad A. Abdel Jaleela, Sally W. Al-Awdana

Abstract:

Diabetes mellitus (DM) is known to exacerbate cerebral ischemic injury. The present study aimed to investigate the anti-oxidant and anti-inflammatory effects of oral supplementation of melatonin (MLN) on cerebral injury caused by middle cerebral artery occlusion and reperfusion (MCAO/Re) in streptozotocin (STZ)-induced hyperglycemic rats. Hyperglycemia was induced by a single injection of STZ (55mg/kg; i.p.), six weeks later the cerebral injury was induced by MCAO/Re. Twenty-four hours after the MCAO/Re the MLN (10 mg/kg) was injected for 14 consecutive days. Results of the present study revealed that MCAO/Re in STZ-induced hyperglycemia in rats causes an increase in the oxidative stress biomarkers; it increased brain lipid peroxidation (measured as malondialdehyde; MDA) and brain level of nitric oxide (NO). Moreover, MCAO/Reproduces a prominent increase in the brain inflammatory markers viz. interleukin-6 (IL-6), interleukin-1β (IL-1β) and tumor necrosis nuclear factor-alpha (TNF-α). Oral treatment of MCAO/Re in STZ-induced hyperglycemic rats with MLN (10 mg/kg) for two weeks restored the brain levels of MDA, GSH, NO, IL-6, IL-1β and the TNF-α. MLN succeeded to suppress the exacerbation of damage in the brain of hyperglycemic rats. These results suggest that daily intake of MLN attenuates the exacerbation of cerebral ischemic injury in a diabetic state, which may be attributed to anti-oxidant and anti-inflammatory effects in the brain.

Keywords: melatonin, brain injury, cerebral ischemia/reperfusion, hyperglycemia, rats

Procedia PDF Downloads 158

Authors: Sanjay Sinha, Mohd Umair Khan

Abstract:

The level of income inequality in India has been worrisome as the World Inequality Report termed it as a “poor and unequal country, with an affluent elite”. As important as income is to understand inequality and deprivation, it is just one dimension. But the historical roots and current realities of inequality and deprivation in India lies in many of the non-income dimensions such as housing, nutrition, education, agency, sense of inclusion etc. which are often ignored, especially in solution-oriented research. The level of inequality and deprivation among the tribal is one such case. There is a corpus of literature establishing that the tribal communities in India are disadvantageous on various grounds. Given their rural geography, issues of access and quality of basic facilities such as education and healthcare are often unaddressed. COVID-19 has further exacerbated this challenge and climate change will make it even more worrying. With this background, a succinct measurement tool at the village level is necessary to design short to medium-term actions with reference to risk mitigation for tribal communities. This research paper examines the level of inequality and deprivation among the tribal communities in the rural areas of Andhra Pradesh state of India using a Multidimensional Inequality and Deprivation Index based on the Alkire-Foster methodology. The methodology is theoretically grounded in the capability approach propounded by Amartya Sen, emphasizing on achieving the “beings and doings” (functionings) an individual reason to value. In the index, the authors have five domains, including Livelihood, Food Security, Education, Health and Housing and these domains are divided into sixteen indicators. This assessment is followed by domain-wise short-term and long-term solutions.

Keywords: Andhra Pradesh, Alkire-Foster methodology, deprivation, inequality, multidimensionality, poverty, tribal

Procedia PDF Downloads 160

Authors: Stephen Vera, Tabitha Black, Charalambos Cleanthous, Ryan Sain

Abstract:

A gender comparison of USA commercial pilots’ demographics and views of CRM, social desirability and locus of control were surveyed. The Aviation safety locus of control (ASLOC) was used to measure external (ASLOC-E) or internal (ASLOC-I) aviation safety locus of control. The gender differences were explored using the ASLOC scores as a categorical variable. A differential comparison of crew resource management (CRM), based on the Federal Aviation Administration’s (FAA) guidelines was conducted. The results indicated that the proportion of female to male respondents matches the current ratio of USA commercial pilots. Moreover, there were no significant differences regarding overall education and the total number of communication classes one took. Regarding CRM issues, there were no significant differences on their views regarding the roles of the PIC, stress, time management, and managing a flight team. The females scored significantly lower on aeronautical decision making (ADM) and communications. There were no significant differences on either the Balanced Inventory of Desirable Responding (BIDR) impression management (IM) or self-deceptive enhancement (SDE). Although there were no overall significant differences on the ASLOC, the females did score higher on the internal subscale than did the males. An additional comparison of socially desirable responding indicates that all scores may be invalid, especially from the female respondents.

Keywords: social desirability, safety locus of control, crew resource management, commercial pilots

Procedia PDF Downloads 256

Authors: Pricillia Priska Sianita

Abstract:

An aesthetic facial profile is one of the goals in Orthodontics treatment. However, this is not easily achieved, especially in patients with Class II Division 1 malocclusion who have the clinical characteristics of convex profile and significant skeletal discrepancy due to mandibular growth deficiency. Malocclusion with skeletal problems require proper treatment timing for growth stimulation, and it must be done in early age and in need of good cooperation from the patient. If this is not done and the patient has passed the growth period, the ideal treatment is orthognathic surgery which is more complicated and more painful. The growth stimulation of skeletal malocclusion requires a careful cephalometric evaluation ranging from diagnosis to determine the parts that require stimulation to post-treatment evaluation to see the success achieved through changes in the measurement of the skeletal parameters shown in the cephalometric analysis. This case report aims to describe skeletal changes cephalometrically that were achieved through orthodontic treatment in growing period. Material and method: Lateral Cephalograms, pre-treatment, and post-treatment of cases of Class II Division 1 malocclusion is selected from a collection of cephalometric radiographic in a private clinic. The Cephalogram is then traced and measured for the skeletal parameters. The result is noted as skeletal condition data of pre-treatment and post-treatment. Furthermore, superimposition is done to see the changes achieved. The results show that growth stimulation through orthodontic treatment can solve the skeletal problem of Class II Division 1 malocclusion and the skeletal changes that occur can be verified through cephalometric analysis. The skeletal changes have an impact on the improvement of patient's facial profile. To sum up, the treatment timing on a skeletal malocclusion is very important to obtain satisfactory results for the improvement of the aesthetic facial profile, and skeletal changes can be verified through cephalometric evaluation of pre- and post-treatment.

Keywords: cephalometric evaluation, class II division 1 malocclusion, growth stimulation, skeletal changes, skeletal problems

Procedia PDF Downloads 249

Authors: Nadia A. Mohamed, Zakaria El-Khayat, Wagdy K. B. Khalil, Mehrez E. El-Naggar

Abstract:

Drug nephrotoxicity is still a problem for patients who have taken drugs for elongated periods or permanently. Ultrasound-assisted sol−gel method was used to prepare hollow structured poroussilica nanoemulsion loaded with sodium salicylate as a model drug. The work was extended to achieve the target of the current work via investigating the protective role of this nanoemulsion model as anti-inflammatory drug or ginger for its antioxidant effect against cisplatin-induced nephrotoxicity in male albino rats. The results clarify that the nanoemulsion model was synthesized using ultrasonic assisted with small size and well stabilization as proved by TEM and DLS analysis. Additionally, blood urea nitrogen (BUN), Serum creatinine (SC) and Urinary total protein (UTP) were increased, and the level of creatinine clearance (Crcl) was decreased. All those were met with disorders in oxidative stress and downregulation in the expression of the nephrin gene. Also, histopathological changes of the kidney tissue were observed. These changes back to normal by treatment with silica nanoparticles loaded sodium salicylate (Si-Sc-NPs), ginger or both. Conclusions oil/water nanoemulsion of (Si-Sc NPs) and ginger showed a protective and promising preventive strategy against nephrotoxicity due to their antioxidant and anti-inflammatory effects, and that offers a new approach in attenuating drug induced nephrotoxicity.

Keywords: sodium salicylate nanoencapsulation, nephrin mRNA, drug nephrotoxicity, cisplatin, experimental rats

Procedia PDF Downloads 201

Authors: A. Bruce Janati, Muhammad Umair Khan, Naif Alghassab, Ibrahim Alzeir, Assem Mahmoud, M. Sammour

Abstract:

Rationale: Lennox-Gastaut syndrome(LGS) is an electro-clinical syndrome composed of the triad of mental retardation, multiple seizure types, and the characteristic generalized slow spike-wave complexes in the EEG. In this article, we report on two patients with LGS whose brain MRI showed dysgenesis of corpus callosum(CC). We review the literature and stress the role of CC in the genesis of secondary bilateral synchrony(SBS). Method: This was a clinical study conducted at King Khalid Hospital. Results: The EEG was consistent with LGS in patient 1 and unilateral slow spike-wave complexes in patient 2. The MRI showed hypoplasia of the splenium of CC in patient 1, and global hypoplasia of CC combined with Joubert syndrome in patient 2. Conclusion: Based on the data, we proffer the following hypotheses: 1-Hypoplasia of CC interferes with functional integrity of this structure. 2-The genu of CC plays a pivotal role in the genesis of secondary bilateral synchrony. 3-Electrodecremental seizures in LGS emanate from pacemakers generated in the brain stem, in particular the mesencephalon projecting abnormal signals to the cortex via thalamic nuclei. 4-Unilateral slow spike-wave complexes in the context of mental retardation and multiple seizure types may represent a variant of LGS, justifying neuroimaging studies.

Keywords: EEG, Lennox-Gastaut syndrome, corpus callosum , MRI

Procedia PDF Downloads 446

Authors: C. E. Sutton, A. Varvani-Farahani

Abstract:

Fatigue damage and life prediction of particle metal matrix composites (PMMCs) under uniaxial and multiaxial loading conditions were investigated. Three PMM composite materials of Al6061/Al2O3/20p-T6, Al6061/Al2O3/22p-T6 and Al6061/SiC/17w-T6 tested under tensile, torsion, and combined tension-torsion fatigue cycling were evaluated with various fatigue damage models. The fatigue damage models of Smith-Watson-Topper (S. W. T.), Ellyin, Brown-Miller, Fatemi-Socie, and Varvani were compared for their capability to assess the fatigue damage of materials undergoing various loading conditions. Fatigue life predication results were then evaluated by implementing material-dependent coefficients that factored in the effects of the particle reinforcement in the earlier developed Varvani model. The critical plane-energy approach incorporated the critical plane as the plane of crack initiation and early stage of crack growth. The strain energy density was calculated on the critical plane incorporating stress and strain components acting on the plane. This approach successfully evaluated fatigue damage values versus fatigue lives within a narrower band for both uniaxial and multiaxial loading conditions as compared with other damage approaches studied in this paper.

Keywords: fatigue damage, life prediction, critical plane approach, energy approach, PMM composites

Procedia PDF Downloads 403

Authors: Kent Salomonsson, Xuefang Zhao, Sara Kallin

Abstract:

Human soft tissue is loaded and deformed by any activity, an effect known as a stress-strain relationship, and is often described by a load and tissue elongation curve. Several advances have been made in the fields of biology and mechanics of soft human tissue. However, there is limited information available on in vivo tissue mechanical characteristics and behavior. Confident mechanical properties of human soft tissue cannot be extrapolated from e.g. animal testing. Thus, there is need for non invasive methods to analyze mechanical characteristics of soft human tissue. In the present study, the internal mechanical conditions of the lower limb, which is subject to an external load, is studied by use of the finite element method. A detailed finite element model of the lower limb is made possible by use of MRI scans. Skin, fat, bones, fascia and muscles are represented separately and the material properties for them are obtained from literature. Previous studies have been shown to address macroscopic deformation features, e.g. indentation depth, to a large extent. However, the detail in which the internal anatomical features have been modeled does not reveal the critical internal strains that may induce hypoxia and/or eventual tissue damage. The results of the present study reveals that lumped material models, i.e. averaging of the material properties for the different constituents, does not capture regions of critical strains in contrast to more detailed models.

Keywords: FEM, tissue, indentation, properties

Procedia PDF Downloads 358

Authors: Heval Serhat Uluk, Sam M. Dakka, Kuldeep Singh, Richard Jefferson-Loveday

Abstract:

This paper will focus on the suitability of a trapped vortex combustor as a candidate for gas turbine combustor objectives to minimize pressure drop across the combustor and investigate aerodynamic performance. Non-reacting simulation of axisymmetric cavity trapped vortex combustors were simulated to investigate the pressure drop for various cavity aspect ratios of 0.3, 0.6, and 1 and for air mass flow rates of 14 m/s, 28 m/s, and 42 m/s. A numerical study of an axisymmetric trapped vortex combustor was carried out by using two-dimensional and three-dimensional computational domains. A comparison study was conducted between Reynolds Averaged Navier Stokes (RANS) k-ε Realizable with enhanced wall treatment and RANS k-ω Shear Stress Transport (SST) models to find the most suitable turbulence model. It was found that the k-ω SST model gives relatively close results to experimental outcomes. The numerical results were validated and showed good agreement with the experimental data. Pressure drop rises with increasing air mass flow rate, and the lowest pressure drop was observed at 0.6 cavity aspect ratio for all air mass flow rates tested, which agrees with the experimental outcome. A mixing enhancement study showed that 30-degree angle air injectors provide improved fuel-air mixing.

Keywords: aerodynamic, computational fluid dynamics, propulsion, trapped vortex combustor

Procedia PDF Downloads 86

Authors: A. V. Shrirao, N. I. Kochar, A. V. Chandewar

Abstract:

The flower extract of Butea monosperma herb has been used traditionally in India for medicinal purposes. The plant has been reported to treat hyperglycemia and associated hyperlipidemia. Hyperlipidemia and oxidative stress are known to accelerate coronary artery disease and progression of atherosclerotic lesions. The present work was undertaken to investigate the possible antihyperlipidemic and antioxidative effect of Butea monosperma flowers on hyperlipidemic rats. Hyperlipidemia was induced in rats by a single intraperitonial (i.p.) injection of Triton WR 1339 (400 mg/kg) and it showed sustained elevated levels of serum cholesterol and triglyceride. Ethanolic extract of Butea monosperma flowers (Et-BM) (250 and 500 mg/kg/day) was administered to normal and hyperlipidemic rats for 14 days. Serum and liver tissue were analyzed at three different time intervals for lipid profile and antioxidants enzymes and the activity were compared to the cholesterol-lowering drug, Atorvastatin (10 mg/kg). Parameters were altered during hyperlipidemia and reverted back to near normal values after Et-BM treatment or standard drug Atorvastatin. Lipid peroxidation decreased whereas the activities of superoxide dismutase, glutathione peroxidase and catalase increased in Et-BM treated rats. Pronounced changes were observed at 500 mg/kg of Et-BM for 2 weeks and it was comparable to the standard drug Atorvastatin. The current study provides strong evidence that Et-BM has a remarkable beneficial effect in treating hyperlipidemia and ROS without any side effects at the dosage and duration studied.

Keywords: antioxidant, butea monopserma, hyperlipidemia, triton WR 1339

Procedia PDF Downloads 318

Authors: Shormin Choudhury, Nazrul Islam, Atiqur Rahman Shaon

Abstract:

High tunnels can provide several benefits to horticultural crops, including environmental stress protection such as hail, frost, excessive rainfall, and high wind. In hot and sunny areas, high tunnel is one of the cooling ways for modifying the microclimate and maximizing crop development. Present study was carried out to assess the effect of different type of high tunnels on banana growth, yield, and fruit quality characteristics. Net houses, poly net houses, UV poly shed houses, and open field (control) conditions are among the experimental treatments. The results revealed that the plants produced in the poly net house condition had maximum pseudo stem height (171.00cm), stem girth (68.66 cm), chlorophyll content (57.63), number of fruits (140), number of hands (9.66), individual fruit weight (125.00) and pulp: peel ratio (3.35) of bananas as compared to the other treatments. Quality parameters like total soluble solid (21.78°Brix), ascorbic acid (10.24 mg/100g), total sugar (25.44%), and reducing sugar (15.75%) were higher in fruits grown in poly net house. The study revealed that the poly net house is the best growing environment for bananas in terms of growth, yield, and quality attributes.

Keywords: shed houses, banana, chlorophyll content, fruit yield, quality

Procedia PDF Downloads 86

Authors: Leman Korkmaz, Bahar Bahtiyar-Saygan

Abstract:

Objective: The COVID-19 pandemic has been affecting the whole world since the beginning of 2020. In addition to health-related and financial effects, there seem to be significant psychological effects as well, among them those related to people’s views and representations of marriage and divorce. Background: Although various impacts of COVID-19 have been investigated since the beginning of the pandemic, there is a limited number of studies on its effects concerning relationships. This research aims to understand how the COVID-19 pandemic affects the views on and representations of marriage and divorce by conducting two studies. Method: In the first study, one-to-one semi-structured interviews were conducted with 31 participants (20 single and 11 married individuals) to investigate their evaluations regarding the effect of COVID-19 on people’s views of marriage in general and their own views of marriage in particular. In the second study, 298 entries on the most frequently used online social platform in Turkey (EkşiSözlük) under two separate headings for COVID-19 impact on marriage and divorce were analyzed, and meaningful thematic units were formed. Results: The findings of the thematic analysis indicated that participants mostly mentioned both the positive and negative effects of COVID-19 on the views and representations of marriage. There were both common (e.g., loneliness, violence, etc.) and distinct (e.g., sexuality, positive and negative effects on attitudes towards marriage, etc.) thematic units between the results of the two studies. Implications: There are considerable implications discussed in light of the literature on Terror Management Theory, Attachment Theory, stress research, and growth perspective.

Keywords: COVID-19 pandemic, divorce, marriage, relationships, representations, views

Procedia PDF Downloads 77

Authors: Md Abdullah Al Faruque, Ram Balachandar

Abstract:

Sudden change of bed condition is frequent in open channel flow. Change of bed condition affects the turbulence characteristics in both streamwise and wall-normal direction. Understanding the turbulence intensity in open channel flow is of vital importance to the modeling of sediment transport and resuspension, bed formation, entrainment, and the exchange of energy and momentum. A comprehensive study was carried out to understand the extent of the effect of Reynolds number and bed roughness on different turbulence characteristics in an open channel flow. Four different bed conditions (impervious smooth bed, impervious continuous rough bed, pervious rough sand bed, and impervious distributed roughness) and two different Reynolds numbers were adopted for this cause. The effect of bed roughness on different turbulence characteristics is seen to be prevalent for most of the flow depth. Effect of Reynolds number on different turbulence characteristics is also evident for flow over different bed, but the extent varies on bed condition. Although the same sand grain is used to create the different rough bed conditions, the difference in turbulence characteristics is an indication that specific geometry of the roughness has an influence on turbulence characteristics. Roughness increases the contribution of the extreme turbulent events which produces very large instantaneous Reynolds shear stress and can potentially influence the sediment transport, resuspension of pollutant from bed and alter the nutrient composition, which eventually affect the sustainability of benthic organisms.

Keywords: open channel flow, Reynolds Number, roughness, turbulence

Procedia PDF Downloads 400

Authors: Manee Hasap, Mongkolchai Hasap, Tasanee Nasae

Abstract:

The purpose of this study was to evaluate the primary caregivers’ knowledge and capabilities for providing quality care to be hospitalized post-hip fracture surgery elderly patients. The theoretical framework of the study was derived from the concepts of dependent care agency in Orem’s Self-Care theory, and family care provision for the elderly and chronically ill patients. 59 subjects were purposively selected. The subjects were primary caregivers of post-operated hip fracture elderly patients who had been admitted to the Orthopaedic Ward of Songklanagarind Hospital. Demographic data of the caregivers and patients were collected by non-participant observation using the evaluation and recording forms. The reliability of caregivers’ knowledge measurement (0.86) was obtained by KR-20 and that of caregivers’ capabilities for post-operative care evaluation form (0.97) obtained from 2 observers by interrater reliability. The data were analyzed using descriptive statistic, which were frequency, percentage, mean, and standard deviation. The result of this study indicated that elderly patients with post-hip fracture surgery had many pre-discharge self care limitations. Approximately, 75% of the caregivers had knowledge to respond to patient’s essential needs at a high level, while the rest (25%) had this knowledge a moderate level. For observation, 57.63% of the subjects had capabilities in care practice at a moderate level; 28.81% had capabilities in care practice at a high level, while 13.56% had at a low level. The result of this study can be used as basic information for patients and caregivers capabilities developing plan especially, providing patients’ activities, accident surveillance and complications prevention for a good life quality of elderly patients after hip surgery both hospitalization and rehabilitation at home.

Keywords: care givers’ knowledge, care givers’ capabilities, elderly hip fracture patients, patients

Procedia PDF Downloads 561

Authors: Aulia Dwi Nastiti

Abstract:

A number of studies and reports on terrorism have continuously addressed the role of internet and online activism to support terrorist and extremist groups. In particular, they stress on social media’s usage that generally serves for the terrorist’s propaganda as well as justification of their causes. While those analyses are important to understand how social media is a vital tool for global network terrorism, they are inadequate to explain the online communication patterns that enable terrorism acts. Beyond apparent online narratives, there is a deep cyber sphere where the very vein of terrorism movement lies. That is a hidden space in the internet called ‘darknet’. Recent investigations, particularly in Middle Eastern context, have shed some lights that this invisible space in the internet is fundamental to maintain the terrorist activities. Despite that, limited number of research examines darknet within the issue of terrorist movements in Indonesian context—where the country is considered quite a hotbed for extremist groups. Therefore, this paper attempts to provide an insight of darknet operation in Indonesian cases. By exploring how the darknet is used by the Indonesian-based extremist groups, this paper maps out communication patterns of terrorist groups on the internet which appear as an intermingled network. It shows the usage of internet is differentiated in different level of anonymity for distinctive purposes. This paper further argues that the emerging terrorist communication network calls for a more comprehensive counterterrorism strategy on the Internet.

Keywords: communication pattern, counterterrorism, darknet, extremist groups, terrorism

Procedia PDF Downloads 293

Authors: Heba Ahmed Abdelaziz, Doaa Tawfik Mohamed Ibrahim

Abstract:

Background: COVID-19 pandemic is the major health problem facing the world recently, causing variable effects on mental health and eating behavior. Aim of the study: Identifying changes in eating patterns and other health behaviors in relation to the anxiety caused by the COVID-19 pandemic lockdown in adult females in Alexandria, Egypt. Method: 344 adult females (20+ years old), were included in online self-administered questionnaire. Results: Severe anxiety symptoms was among 34.6% of the studied females especially; those aged 25-40 years, married, non-working or student females, females who had change in their work routine (half or full time from home). Homemade pastries and bakery product then beverages followed by fresh fruits and vegetables were frequently consumed by the studied females than before lockdown while fast foods were decreased during lockdown. Overweight and obesity were high among most of the participants with different grades of anxiety symptoms. Females with moderate and severe anxiety symptoms reported increase in appetite and body weight with irregular sleeping during lockdown. Conclusion: the current study concluded that stressful situations like lockdown due to COVID-19 pandemic is associated with anxiety (severe, moderate, mild then minimal, respectively) along with changes in eating habits, physical activity, sleeping pattern and smoking.

Keywords: COVID-19, lockdown, females, anxiety, eating, stress, lifestyle

Procedia PDF Downloads 189