Search results for: lower back
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 6974

Search results for: lower back

6584 A Top-down vs a Bottom-up Approach on Lower Extremity Motor Recovery and Balance Following Acute Stroke: A Randomized Clinical Trial

Authors: Vijaya Kumar, Vidayasagar Pagilla, Abraham Joshua, Rakshith Kedambadi, Prasanna Mithra

Abstract:

Background: Post stroke rehabilitation are aimed to accelerate for optimal sensorimotor recovery, functional gain and to reduce long-term dependency. Intensive physical therapy interventions can enhance this recovery as experience-dependent neural plastic changes either directly act at cortical neural networks or at distal peripheral level (muscular components). Neuromuscular Electrical Stimulation (NMES), a traditional bottom-up approach, mirror therapy (MT), a relatively new top down approach have found to be an effective adjuvant treatment methods for lower extremity motor and functional recovery in stroke rehabilitation. However there is a scarcity of evidence to compare their therapeutic gain in stroke recovery.Aim: To compare the efficacy of neuromuscular electrical stimulation (NMES) and mirror therapy (MT) in very early phase of post stroke rehabilitation addressed to lower extremity motor recovery and balance. Design: observer blinded Randomized Clinical Trial. Setting: Neurorehabilitation Unit, Department of Physical Therapy, Tertiary Care Hospitals. Subjects: 32 acute stroke subjects with first episode of unilateral stroke with hemiparesis, referred for rehabilitation (onset < 3 weeks), Brunnstorm lower extremity recovery stages ≥3 and MMSE score more than 24 were randomized into two group [Group A-NMES and Group B-MT]. Interventions: Both the groups received eclectic approach to remediate lower extremity recovery which includes treatment components of Roods, Bobath and Motor learning approaches for 30 minutes a day for 6 days. Following which Group A (N=16) received 30 minutes of surface NMES training for six major paretic muscle groups (gluteus maximus and medius,quadriceps, hamstrings, tibialis anterior and gastrocnemius). Group B (N=16) was administered with 30 minutes of mirror therapy sessions to facilitate lower extremity motor recovery. Outcome measures: Lower extremity motor recovery, balance and activities of daily life (ADLs) were measured by Fugyl Meyer Assessment (FMA-LE), Berg Balance Scale (BBS), Barthel Index (BI) before and after intervention. Results: Pre Post analysis of either group across the time revealed statistically significant improvement (p < 0.001) for all the outcome variables for the either group. All parameters of NMES had greater change scores compared to MT group as follows: FMA-LE (25.12±3.01 vs. 23.31±2.38), BBS (35.12±4.61 vs. 34.68±5.42) and BI (40.00±10.32 vs. 37.18±7.73). Between the groups comparison of pre post values showed no significance with FMA-LE (p=0.09), BBS (p=0.80) and BI (p=0.39) respectively. Conclusion: Though either groups had significant improvement (pre to post intervention), none of them were superior to other in lower extremity motor recovery and balance among acute stroke subjects. We conclude that eclectic approach is an effective treatment irrespective of NMES or MT as an adjunct.

Keywords: balance, motor recovery, mirror therapy, neuromuscular electrical stimulation, stroke

Procedia PDF Downloads 264
6583 Soybean Lecithin Based Reverse Micellar Extraction of Pectinase from Synthetic Solution

Authors: Sivananth Murugesan, I. Regupathi, B. Vishwas Prabhu, Ankit Devatwal, Vishnu Sivan Pillai

Abstract:

Pectinase is an important enzyme which has a wide range of applications including textile processing and bioscouring of cotton fibers, coffee and tea fermentation, purification of plant viruses, oil extraction etc. Selective separation and purification of pectinase from fermentation broth and recover the enzyme form process stream for reuse are cost consuming process in most of the enzyme based industries. It is difficult to identify a suitable medium to enhance enzyme activity and retain its enzyme characteristics during such processes. The cost effective, selective separation of enzymes through the modified Liquid-liquid extraction is of current research interest worldwide. Reverse micellar extraction, globally acclaimed Liquid-liquid extraction technique is well known for its separation and purification of solutes from the feed which offers higher solute specificity and partitioning, ease of operation and recycling of extractants used. Surfactant concentrations above critical micelle concentration to an apolar solvent form micelles and addition of micellar phase to water in turn forms reverse micelles or water-in-oil emulsions. Since, electrostatic interaction plays a major role in the separation/purification of solutes using reverse micelles. These interaction parameters can be altered with the change in pH, addition of cosolvent, surfactant and electrolyte and non-electrolyte. Even though many chemical based commercial surfactant had been utilized for this purpose, the biosurfactants are more suitable for the purification of enzymes which are used in food application. The present work focused on the partitioning of pectinase from the synthetic aqueous solution within the reverse micelle phase formed by a biosurfactant, Soybean Lecithin dissolved in chloroform. The critical micelle concentration of soybean lecithin/chloroform solution was identified through refractive index and density measurements. Effect of surfactant concentrations above and below the critical micelle concentration was considered to study its effect on enzyme activity, enzyme partitioning within the reverse micelle phase. The effect of pH and electrolyte salts on the partitioning behavior was studied by varying the system pH and concentration of different salts during forward and back extraction steps. It was observed that lower concentrations of soybean lecithin enhanced the enzyme activity within the water core of the reverse micelle with maximizing extraction efficiency. The maximum yield of pectinase of 85% with a partitioning coefficient of 5.7 was achieved at 4.8 pH during forward extraction and 88% yield with a partitioning coefficient of 7.1 was observed during backward extraction at a pH value of 5.0. However, addition of salt decreased the enzyme activity and especially at higher salt concentrations enzyme activity declined drastically during both forward and back extraction steps. The results proved that reverse micelles formed by Soybean Lecithin and chloroform may be used for the extraction of pectinase from aqueous solution. Further, the reverse micelles can be considered as nanoreactors to enhance enzyme activity and maximum utilization of substrate at optimized conditions, which are paving a way to process intensification and scale-down.

Keywords: pectinase, reverse micelles, soybean lecithin, selective partitioning

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6582 The Mainspring of Controlling of Low Pressure Steam Drum at Lower Pressure than Its Design for Adjusting the Urea Synthesis Pressure

Authors: Reza Behtash, Enayat Enayati

Abstract:

The pool condenser is in principal a horizontal reactor, containing a bundle of U-tubes for heat exchange, coupling to low pressure steam drum. Condensation of gas takes place in a condensed pool around the tubes of the condenser. The heat of condensation is removed by the generation of low pressure steam on the inner tube side of the bundle. A circulation pump transfers ample boiler feed water to these tubes. The pressure of the steam generated influenced the heat flux. Changing the steam pressure means changing the steam condensate temperature and therefore the temperature difference between the tube side and the shell side. 2NH3 + CO2 ↔ NH2COONH4 + Heat. This reaction is exothermic and according to Le Chatelier's Principle if the heat is not removed enough, it will come back to left side and generate of the gas and so the Urea synthesis pressure will rise. The most principal reasons for high Urea synthesis pressure are non proportional of Ammonia/Dioxide Carbon ratio and too high a pressure in low pressure steam drum. Proportional of Ammonia/Dioxide Carbon ratio is 3.0 and normal pressure for low pressure steam drum is 4.5 bar. As regards these conditions were proportional but we could not control the synthesis pressure the plant endangered, therefore we had to control the steam drum pressure at about 3.5 bar. While we opened the pool condenser, we found the partition plate used to divide inlet and outlet boiler feed water to tubes, was broken partially and so amount of boiler feed water bypass the tubes and the heat was not removed totally and it resulted in the generation of gases and high pressure in synthesis.

Keywords: boiler, pressure, pool condenser, partition plate

Procedia PDF Downloads 366
6581 Subsea Processing: Deepwater Operation and Production

Authors: Md Imtiaz, Sanchita Dei, Shubham Damke

Abstract:

In recent years, there has been a rapidly accelerating shift from traditional surface processing operations to subsea processing operation. This shift has been driven by a number of factors including the depletion of shallow fields around the world, technological advances in subsea processing equipment, the need for production from marginal fields, and lower initial upfront investment costs compared to traditional production facilities. Moving production facilities to the seafloor offers a number of advantage, including a reduction in field development costs, increased production rates from subsea wells, reduction in the need for chemical injection, minimization of risks to worker ,reduction in spills due to hurricane damage, and increased in oil production by enabling production from marginal fields. Subsea processing consists of a range of technologies for separation, pumping, compression that enables production from offshore well without the need for surface facilities. At present, there are two primary technologies being used for subsea processing: subsea multiphase pumping and subsea separation. Multiphase pumping is the most basic subsea processing technology. Multiphase pumping involves the use of boosting system to transport the multiphase mixture through pipelines to floating production vessels. The separation system is combined with single phase pumps or water would be removed and either pumped to the surface, re-injected, or discharged to the sea. Subsea processing can allow for an entire topside facility to be decommissioned and the processed fluids to be tied back to a new, more distant, host. This type of application reduces costs and increased both overall facility and integrity and recoverable reserve. In future, full subsea processing could be possible, thereby eliminating the need for surface facilities.

Keywords: FPSO, marginal field, Subsea processing, SWAG

Procedia PDF Downloads 396
6580 Determination of Poisson’s Ratio and Elastic Modulus of Compression Textile Materials

Authors: Chongyang Ye, Rong Liu

Abstract:

Compression textiles such as compression stockings (CSs) have been extensively applied for the prevention and treatment of chronic venous insufficiency of lower extremities. The involvement of multiple mechanical factors such as interface pressure, frictional force, and elastic materials make the interactions between lower limb and CSs to be complex. Determination of Poisson’s ratio and elastic moduli of CS materials are critical for constructing finite element (FE) modeling to numerically simulate a complex interactive system of CS and lower limb. In this study, a mixed approach, including an analytic model based on the orthotropic Hooke’s Law and experimental study (uniaxial tension testing and pure shear testing), has been proposed to determine Young’s modulus, Poisson’s ratio, and shear modulus of CS fabrics. The results indicated a linear relationship existing between the stress and strain properties of the studied CS samples under controlled stretch ratios (< 100%). The newly proposed method and the determined key mechanical properties of elastic orthotropic CS fabrics facilitate FE modeling for analyzing in-depth the effects of compression material design on their resultant biomechanical function in compression therapy.

Keywords: elastic compression stockings, Young’s modulus, Poisson’s ratio, shear modulus, mechanical analysis

Procedia PDF Downloads 97
6579 The Nutritional Status and the Kidney Function in Older Patients

Authors: Magdalena Barbara Kaziuk, Waldemar Kosiba

Abstract:

Background: Obesity, particularly abdominal type, lead to accelerated progress of atherosclerosis and thus affects the functioning of various human organs. Non-HDL cholesterol includes residual risk of the cardiovascular diseases which persists in patients after achieved recommended level of LDL cholesterol. The maintenance of normal body mass index plays a particularly important role in both the prevention and treatment of chronic diseases. Materials and Methods: The study covered 96 patients (55 females, 42 males, age 66,9 +/-10,2 years). The nutritional status was determined with the Waist to Height Ratio (WHtR) and the Waist to Hip Ratio (WHR). A function of the kidney was evaluated by calculating the estimated glomerular filtration rate (eGFR) using the MDRD formula. Non-high-density lipoprotein cholesterol (non-HDL) is simply the difference between the total cholesterol concentration and the HDL cholesterol concentration. Results: The higher was level of non-HDL cholesterol, the lower eGFR had studied subjects (p<0.001). Significant correlation was found between higher WHtR and lower the eGFR (p=0.002). Also underweight (30% of patient) led to obtaining lower values of eGFR in subjects over 65 years old. The poorer nutrition the lower was glomerular filtration rate. Conclusions: Nutritional statuses of patients have a significant impact on the level of kidney function. Not only accumulated excess fat in the abdominal area, but also its deficiency affects the deterioration in renal filtration. Higher level of non-HDL not only raises the residual risk of the heart disease but also influences on kidney by worsening eGFR. Proper diet in connection with physical activity should lead to achieving good nutrition in these patients and protect their kidney function.

Keywords: nutrition, non-HDL cholesterol, glomerular filtration rate, lifestyle

Procedia PDF Downloads 255
6578 Combining Diffusion Maps and Diffusion Models for Enhanced Data Analysis

Authors: Meng Su

Abstract:

High-dimensional data analysis often presents challenges in capturing the complex, nonlinear relationships and manifold structures inherent to the data. This article presents a novel approach that leverages the strengths of two powerful techniques, Diffusion Maps and Diffusion Probabilistic Models (DPMs), to address these challenges. By integrating the dimensionality reduction capability of Diffusion Maps with the data modeling ability of DPMs, the proposed method aims to provide a comprehensive solution for analyzing and generating high-dimensional data. The Diffusion Map technique preserves the nonlinear relationships and manifold structure of the data by mapping it to a lower-dimensional space using the eigenvectors of the graph Laplacian matrix. Meanwhile, DPMs capture the dependencies within the data, enabling effective modeling and generation of new data points in the low-dimensional space. The generated data points can then be mapped back to the original high-dimensional space, ensuring consistency with the underlying manifold structure. Through a detailed example implementation, the article demonstrates the potential of the proposed hybrid approach to achieve more accurate and effective modeling and generation of complex, high-dimensional data. Furthermore, it discusses possible applications in various domains, such as image synthesis, time-series forecasting, and anomaly detection, and outlines future research directions for enhancing the scalability, performance, and integration with other machine learning techniques. By combining the strengths of Diffusion Maps and DPMs, this work paves the way for more advanced and robust data analysis methods.

Keywords: diffusion maps, diffusion probabilistic models (DPMs), manifold learning, high-dimensional data analysis

Procedia PDF Downloads 78
6577 Effects of Diluent Gas Velocity on Formation of Moderate or Intense Low-Oxygen Dilution Combustion with Fuel Spray for Gas Turbine

Authors: ChunLoon Cha, HoYeon Lee, SangSoon Hwang

Abstract:

Mild combustion is characterized with its distinguished features, such as suppressed pollutant emission, homogeneous temperature distribution, reduced noise and thermal stress. However, most studies for MILD combustion have been focused on gas phase fuel. Therefore further study on MILD combustion using liquid fuel is needed for the application to liquid fueled gas turbine especially. In this work, we will focus on numerical simulation of the effects of diluent gas velocity on the formation of liquid fuel MILD combustion used in gas turbine area. A series of numerical simulations using Ansys fluent 18.2 have been carried out in order to investigate the detail effect of the flow field in the furnace on the formation of MILD combustion. The operating conditions were fixed at relatively lower heat intensity of 1.28 MW/m³ atm and various global equivalence ratios were changed. The results show that the local high temperature region was decreased and the flame temperature was uniformly distributed due to high velocity of diluted burnt gas. The increasing of diluted burnt gas velocity can be controlled by open ratio of adapter size. It was found that the maximum temperature became lower than 1800K and the average temperature was lower than 1500K that thermal NO formation was suppressed.

Keywords: MILD combustion, spray combustion, liquid fuel, diluent gas velocity, low NOx emission

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6576 Estimation of Geotechnical Parameters by Comparing Monitoring Data with Numerical Results: Case Study of Arash–Esfandiar-Niayesh Under-Passing Tunnel, Africa Tunnel, Tehran, Iran

Authors: Aliakbar Golshani, Seyyed Mehdi Poorhashemi, Mahsa Gharizadeh

Abstract:

The under passing tunnels are strongly influenced by the soils around. There are some complexities in the specification of real soil behavior, owing to the fact that lots of uncertainties exist in soil properties, and additionally, inappropriate soil constitutive models. Such mentioned factors may cause incompatible settlements in numerical analysis with the obtained values in actual construction. This paper aims to report a case study on a specific tunnel constructed by NATM. The tunnel has a depth of 11.4 m, height of 12.2 m, and width of 14.4 m with 2.5 lanes. The numerical modeling was based on a 2D finite element program. The soil material behavior was modeled by hardening soil model. According to the field observations, the numerical estimated settlement at the ground surface was approximately four times more than the measured one, after the entire installation of the initial lining, indicating that some unknown factors affect the values. Consequently, the geotechnical parameters are accurately revised by a numerical back-analysis using laboratory and field test data and based on the obtained monitoring data. The obtained result confirms that typically, the soil parameters are conservatively low-estimated. And additionally, the constitutive models cannot be applied properly for all soil conditions.

Keywords: NATM tunnel, initial lining, laboratory test data, numerical back-analysis

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6575 An Unusual Case of Extensive, Unilateral, Idiopathic Dental Resorption

Authors: Ceri McIntosh

Abstract:

A 25-year-old male was referred to the Maxillofacial department by his general dental practitioner with a complaint of mobile teeth. Medically he was well though he took mirtazapine for anxiety. He was found to have had previous extractions of the lower right second premolar and first molar, with grade 2 mobility of the upper right first and second molars and lower right lateral incisor. Radiographically there was significant external root resorption of these teeth, which were subsequently extracted. Over the next 18 months, the resorption continued around multiple teeth on the right side, and when the mobile teeth were removed, they showed no remaining root, including loss of coronal dentine, leaving only an enamel shell. No cause has been identified either histologically or in the patient’s blood work. A review of relevant literature will be included in this case report.

Keywords: case report, idiopathic resorption, idiopathic root resorption, external resorption

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6574 Force Distribution and Muscles Activation for Ankle Instability Patients with Rigid and Kinesiotape while Standing

Authors: Norazlin Mohamad, Saiful Adli Bukry, Zarina Zahari, Haidzir Manaf, Hanafi Sawalludin

Abstract:

Background: Deficit in neuromuscular recruitment and decrease force distribution were the common problems among ankle instability patients due to altered joint kinematics that lead to recurrent ankle injuries. Rigid Tape and KT Tape had widely been used as therapeutic and performance enhancement tools in ankle stability. However the difference effect between this two tapes is still controversial. Objective: To investigate the different effect between Rigid Tape and KT Tape on force distribution and muscle activation among ankle instability patients while standing. Study design: Crossover trial. Participants: 27 patients, age between 18 to 30 years old participated in this study. All the subjects were applied with KT Tape & Rigid Tape on their affected ankle with 3 days of interval for each intervention. The subjects were tested with their barefoot (without tape) first to act as a baseline before proceeding with KT Tape, and then with Rigid Tape. Result: There were no significant difference on force distribution at forefoot and back-foot for both tapes while standing. However the mean data shows that Rigid Tape has the highest force distribution at back-foot rather than forefoot when compared with KT Tape that had more force distribution at forefoot while standing. Regarding muscle activation (Peroneus Longus), results showed significant difference between Rigid Tape and KT Tape (p= 0.048). However, there was no significant difference on Tibialis Anterior muscle activation between both tapes while standing. Conclusion: The results indicated that Peroneus longus muscle was more active when applied Rigid Tape rather than KT Tape in ankle instability patients while standing.

Keywords: ankle instability, kinematic, muscle activation, force distribution, Rigid Tape, KT tape

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6573 Efficient Depolymerization of Polyethylene terephthalate (PET) Using Bimetallic Catalysts

Authors: Akmuhammet Karayev, Hassam Mazhar, Mamdouh Al Harthi

Abstract:

Polyethylene terephthalate (PET) recycling stands as a pivotal solution in combating plastic pollution and fostering a circular economy. This study addresses the catalytic glycolysis of PET, a key step in its recycling process, using synthesized catalysts. Our focus lies in elucidating the catalytic mechanism, optimizing reaction kinetics, and enhancing reactor design for efficient PET conversion. We synthesized anionic clays tailored for PET glycolysis and comprehensively characterized them using XRD, FT-IR, BET, DSC, and TGA techniques, confirming their suitability as catalysts. Through systematic parametric studies, we optimized reaction conditions to achieve complete PET conversion to bis hydroxy ethylene terephthalate (BHET) with over 75% yield within 2 hours at 200°C, employing a minimal catalyst concentration of 0.5%. These results underscore the catalysts' exceptional efficiency and sustainability, positioning them as frontrunners in catalyzing PET recycling processes. Furthermore, we demonstrated the recyclability of the obtained BHETs by repolymerizing them back to PET without the need for a catalyst. Heating the BHETs in a distillation unit facilitated their conversion back to PET, highlighting the closed-loop potential of our recycling approach. Our work embodies a significant leap in catalytic glycolysis kinetics, driven by sustainable catalysts, offering rapid and high-impact PET conversion while minimizing environmental footprint. This breakthrough not only sets new benchmarks for efficiency in PET recycling but also exemplifies the pivotal role of catalysis and reaction engineering in advancing sustainable materials management.

Keywords: polymer recycling, catalysis, circular economy, glycolysis

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6572 Estimation Model for Concrete Slump Recovery by Using Superplasticizer

Authors: Chaiyakrit Raoupatham, Ram Hari Dhakal, Chalermchai Wanichlamlert

Abstract:

This paper is aimed to introduce the solution of concrete slump recovery using chemical admixture type-F (superplasticizer, naphthalene base) to the practice, in order to solve unusable concrete problem due to concrete loss its slump, especially for those tropical countries that have faster slump loss rate. In the other hand, randomly adding superplasticizer into concrete can cause concrete to segregate. Therefore, this paper also develops the estimation model used to calculate amount of second dose of superplasticizer need for concrete slump recovery. Fresh properties of ordinary Portland cement concrete with volumetric ratio of paste to void between aggregate (paste content) of 1.1-1.3 with water-cement ratio zone of 0.30 to 0.67 and initial superplasticizer (naphthalene base) of 0.25%- 1.6% were tested for initial slump and slump loss for every 30 minutes for one and half hour by slump cone test. Those concretes with slump loss range from 10% to 90% were re-dosed and successfully recovered back to its initial slump. Slump after re-dosed was tested by slump cone test. From the result, it has been concluded that, slump loss was slower for those mix with high initial dose of superplasticizer due to addition of superplasticizer will disturb cement hydration. The required second dose of superplasticizer was affected by two major parameter, which were water-cement ratio and paste content, where lower water-cement ratio and paste content cause an increase in require second dose of superplasticizer. The amount of second dose of superplasticizer is higher as the solid content within the system is increase, solid can be either from cement particles or aggregate. The data was analyzed to form an equation use to estimate the amount of second dosage requirement of superplasticizer to recovery slump to its original.

Keywords: estimation model, second superplasticizer dosage, slump loss, slump recovery

Procedia PDF Downloads 183
6571 Stigmatization of Individuals Who Receive Mental Health Treatment and the Role of Social Media: A Cross-Generational Cohort Design and Extension

Authors: Denise Ben-Porath, Tracy Masterson

Abstract:

In the past, individuals who struggled with and sought treatment for mental health difficulties were stigmatized. However, the current generation holds more open attitudes around mental health issues. Indeed, public figures such as Demi Lovato, Naomi Osaka, and Simone Biles have taken to social media to break the silence around mental health, discussing their own struggles and the benefits of treatment. Thus, there is considerable reason to believe that this generation would hold fewer stigmatizing attitudes toward mental health difficulties and treatment compared to previous ones. In this study, we explored possible changes in stigma on mental health diagnosis and treatment seeking behavior between two generations: Gen Z, the current generation, and Gen X, those born between 1965-1980. It was hypothesized that Gen Z would hold less stigmatizing views on mental illness than Gen X. To examine possible changes in stigma attitudes between these two generations, we conducted a cross-generational cohort design by using the same methodology employed 20 years ago from the Ben-Porath (2002) study. Thus, participants were randomly assigned to read one of the following four case vignettes employed in the Ben-Porath (2002) study: (a) “Tom” who has received psychotherapy due to depression (b) “Tom” who has been depressed but received no psychological help, (c) “Tom” who has received medical treatment due to a back pain, or (d) “Tom” who had a back pain but did not receive medical attention. After reading the vignette, participants rated “Tom” on various personality dimensions using the IFQ Questionnaire and answered questions about their frequency of social media use and willingness to seek mental health treatment on a scale from 1-10. Identical to the results 20 years prior, a significant main effect was found for diagnosis with “Tom” being viewed in more negative terms when he was described as having depression vs. a medical condition (back pain) [F (1, 376) = 126.53, p < .001]. However, in the study conducted 20 years earlier, a significant interaction was found between diagnosis and help-seeking behavior [F (1, 376) = 8.28, p < .005]. Specifically, “Tom” was viewed in the most negative terms when described as depressed and seeking treatment. Alternatively, the current study failed to find a significant interaction between depression and help seeking behavior. These findings suggest that while individuals who hold a mental health diagnosis may still be stigmatized as they were 20 years prior, seeking treatment for mental health issues may be less so. Findings are discussed in the context of social media use and its impact on destigmatization.

Keywords: stigma, mental illness, help-seeking, social media

Procedia PDF Downloads 57
6570 The Acute Effects of Higher Versus Lower Load Duration and Intensity on Morphological and Mechanical Properties of the Healthy Achilles Tendon: A Randomized Crossover Trial

Authors: Eman Merza, Stephen Pearson, Glen Lichtwark, Peter Malliaras

Abstract:

The Achilles tendon (AT) exhibits volume changes related to fluid flow under acute load which may be linked to changes in stiffness. Fluid flow provides a mechanical signal for cellular activity and may be one mechanism that facilitates tendon adaptation. This study aimed to investigate whether isometric intervention involving a high level of load duration and intensity could maximize the immediate reduction in AT volume and stiffness compared to interventions involving a lower level of load duration and intensity. Sixteen healthy participants (12 males, 4 females; age= 24.4 ± 9.4 years; body mass= 70.9 ± 16.1 kg; height= 1.7 ± 0.1 m) performed three isometric interventions of varying levels of load duration (2 s and 8 s) and intensity (35% and 75% maximal voluntary isometric contraction) over a 3 week period. Freehand 3D ultrasound was used to measure free AT volume (at rest) and length (at 35%, 55%, and 75% of maximum plantarflexion force) pre- and post-interventions. The slope of the force-elongation curve over these force levels represented individual stiffness (N/mm). Large reductions in free AT volume and stiffness resulted in response to long-duration high-intensity loading whilst less reduction was produced with a lower load intensity. In contrast, no change in free AT volume and a small increase in AT stiffness occurred with lower load duration. These findings suggest that the applied load on the AT must be heavy and sustained for a long duration to maximize immediate volume reduction, which might be an acute response that enables optimal long-term tendon adaptation via mechanotransduction pathways.

Keywords: Achilles tendon, volume, stiffness, free tendon, 3d ultrasound

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6569 Numerical Investigation of Material Behavior During Non-Equal Channel Multi Angular Extrusion

Authors: Mohamed S. El-Asfoury, Ahmed Abdel-Moneim, Mohamed N. A. Nasr

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The current study uses finite element modeling to investigate and analyze a modified form of the from the conventional equal channel multi-angular pressing (ECMAP), using non-equal channels, on the workpiece material plastic deformation. The modified process non-equal channel multi-angular extrusion (NECMAE) is modeled using two-dimensional plane strain finite element model built using the commercial software ABAQUS. The workpiece material used is pure aluminum. The model was first validated by comparing its results to analytical solutions for single-pass equal channel angular extrusion (ECAP), as well as previously published data. After that, the model was used to examine the effects of different % of reductions of the area (for the second stage) on material plastic deformation, corner gap, and required the load. Three levels of reduction in the area were modeled; 10%, 30%, and 50%, and compared to single-pass and double-pass ECAP. Cases with a higher reduction in the area were found to have smaller corner gaps, higher and much uniform plastic deformation, as well as higher required loads. The current results are mainly attributed to the back pressure effects exerted by the second stage, as well as strain hardening effects experienced during the first stage.

Keywords: non-equal channel angular extrusion, multi-pass, sever plastic deformation, back pressure, Finite Element Modelling (FEM)

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6568 Peripheral Neuropathy after Locoregional Anesthesia

Authors: Dalila Chaid, Bennameur Fedilli, Mohammed Amine Bellelou

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The study focuses on the experience of lower-limb amputees, who face both physical and psychological challenges due to their disability. Chronic neuropathic pain and various types of limb pain are common in these patients. They often require orthopaedic interventions for issues such as dressings, infection, ulceration, and bone-related problems. Research Aim: The aim of this study is to determine the most suitable anaesthetic technique for lower-limb amputees, which can provide them with the greatest comfort and prolonged analgesia. The study also aims to demonstrate the effectiveness and cost-effectiveness of ultrasound-guided local regional anaesthesia (LRA) in this patient population. Methodology: The study is an observational analytical study conducted over a period of eight years, from 2010 to 2018. It includes a total of 955 cases of revisions performed on lower limb stumps. The parameters analyzed in this study include the effectiveness of the block and the use of sedation, the duration of the block, the post-operative visual analog scale (VAS) scores, and patient comfort. Findings: The study findings highlight the benefits of ultrasound-guided LRA in providing comfort by optimizing post-operative analgesia, which can contribute to psychological and bodily repair in lower-limb amputees. Additionally, the study emphasizes the use of alpha2 agonist adjuvants with sedative and analgesic properties, long-acting local anaesthetics, and larger volumes for better outcomes. Theoretical Importance: This study contributes to the existing knowledge by emphasizing the importance of choosing an appropriate anaesthetic technique for lower-limb amputees. It highlights the potential of ultrasound-guided LRA and the use of specific adjuvants and local anaesthetics in improving post-operative analgesia and overall patient outcomes. Data Collection and Analysis Procedures: Data for this study were collected through the analysis of medical records and relevant documentation related to the 955 cases included in the study. The effectiveness of the anaesthetic technique, duration of the block, post-operative pain scores, and patient comfort were analyzed using statistical methods. Question Addressed: The study addresses the question of which anaesthetic technique would be most suitable for lower-limb amputees to provide them with optimal comfort and prolonged analgesia. Conclusion: The study concludes that ultrasound-guided LRA, along with the use of alpha2 agonist adjuvants, long-acting local anaesthetics, and larger volumes, can be an effective approach in providing comfort and improving post-operative analgesia for lower-limb amputees. This technique can potentially contribute to the psychological and bodily repair of these patients. The findings of this study have implications for clinical practice in the management of lower-limb amputees, highlighting the importance of personalized anaesthetic approaches for better outcomes.

Keywords: neuropathic pain, ultrasound-guided peripheral nerve block, DN4 quiz, EMG

Procedia PDF Downloads 44
6567 The Environmental Influence on Slow Learners' Learning Achievement

Authors: Niphattha Hannapha

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This paper examines how the classroom environment influences slow learners’ learning achievement; it focuses on how seating patterns affect students’ behaviours and which patterns best contribute to students’ learning performance. The researcher studied how slow learners’ characteristics and seating patterns influenced their behaviours and performance at Ban Hin Lad School. As a nonparticipant observation, the target groups included 15 slow learners from Prathomsueksa (Grades) 4 and 5. Students’ behaviours were recorded during their learning activities in order to minimize their reading and written expression disorder in Thai language tutorials. The result showed four seating patterns and two behaviors which obstructed students’ learning. The average of both behaviours mostly occurred when students were seated with patterns 1 (the seat facing the door, with the corridor alongside) and 3 (the seat alongside the door, facing the aisle) respectively. Seating patterns 1 and 3 demonstrated visibility (the front and side) of a walking path with two-way movement. However, seating patterns 2 (seating with the door alongside and the aisle at the back) and 4 (sitting with the door at the back and the aisle alongside) demonstrated visibility (the side) of a walking path with one-way movement. In Summary, environmental design is important to enhance concentration in slow learners who have reading and writing disabilities. This study suggests that students should be seated where they can have the least visibility of movement to help them increase continuous learning. That means they can have a better chance of developing reading and writing abilities in comparison with other patterns of seating.

Keywords: slow learning, interior design, interior environment, classroom

Procedia PDF Downloads 187
6566 Women Domestic Violence in Nepalese Society: A Case Study of Armala Village Development Committee, Kaski

Authors: Rajani Bogati, Gopini Pathak

Abstract:

Women living in husband’s home (second home) after getting married is a common culture in Nepalese society. Most of the marriages are arranged between the mutual understandings of their parents as per their cultural practice. Culturally, arranged marriage system protects women in the society. Even though, women domestic violence is also still alive in the society. It depends upon the family class, ethnicity, caste, religion etc. Lower class (poor) family always try to get marriage from the higher class (rich) family of girl and also try to send their girl in higher class family. This study analysis the freedom of women of Armala Village Development Committee, Kaski district on the base of the family class of girl where she born (First home). 88% women are getting more respect in their second home if their family class of first home and second homes are same. They feel more comfortable and freedom in their second home. 79% of Women are suffering from domestic violence while the marriage between the boys from higher class and the girls from lower class. But less than 10% women are getting distress from violence if the marriage is accompanied between the girls from higher class and the boys from lower class. Less domestic violence is seem where the both families are educated, even though they are from different class. This study recommends that the society should be educated first to reduce women domestic violence.

Keywords: arranged marriage, women, family class, domestic violence

Procedia PDF Downloads 295
6565 Effect of Curing Temperature on the Textural and Rheological of Gelatine-SDS Hydrogels

Authors: Virginia Martin Torrejon, Binjie Wu

Abstract:

Gelatine is a protein biopolymer obtained from the partial hydrolysis of animal tissues which contain collagen, the primary structural component in connective tissue. Gelatine hydrogels have attracted considerable research in recent years as an alternative to synthetic materials due to their outstanding gelling properties, biocompatibility and compostability. Surfactants, such as sodium dodecyl sulfate (SDS), are often used in hydrogels solutions as surface modifiers or solubility enhancers, and their incorporation can influence the hydrogel’s viscoelastic properties and, in turn, its processing and applications. Literature usually focuses on studying the impact of formulation parameters (e.g., gelatine content, gelatine strength, additives incorporation) on gelatine hydrogels properties, but processing parameters, such as curing temperature, are commonly overlooked. For example, some authors have reported a decrease in gel strength at lower curing temperatures, but there is a lack of research on systematic viscoelastic characterisation of high strength gelatine and gelatine-SDS systems at a wide range of curing temperatures. This knowledge is essential to meet and adjust the technological requirements for different applications (e.g., viscosity, setting time, gel strength or melting/gelling temperature). This work investigated the effect of curing temperature (10, 15, 20, 23 and 25 and 30°C) on the elastic modulus (G’) and melting temperature of high strength gelatine-SDS hydrogels, at 10 wt% and 20 wt% gelatine contents, by small-amplitude oscillatory shear rheology coupled with Fourier Transform Infrared Spectroscopy. It also correlates the gel strength obtained by rheological measurements with the gel strength measured by texture analysis. Gelatine and gelatine-SDS hydrogels’ rheological behaviour strongly depended on the curing temperature, and its gel strength and melting temperature can be slightly modified to adjust it to given processing and applications needs. Lower curing temperatures led to gelatine and gelatine-SDS hydrogels with considerably higher storage modulus. However, their melting temperature was lower than those gels cured at higher temperatures and lower gel strength. This effect was more considerable at longer timescales. This behaviour is attributed to the development of thermal-resistant structures in the lower strength gels cured at higher temperatures.

Keywords: gelatine gelation kinetics, gelatine-SDS interactions, gelatine-surfactant hydrogels, melting and gelling temperature of gelatine gels, rheology of gelatine hydrogels

Procedia PDF Downloads 82
6564 Correlation between Body Mass Index and Blood Sugar/Serum Lipid Levels in Fourth-Grade Boys in Japan

Authors: Kotomi Yamashita, Hiromi Kawasaki, Satoko Yamasaki, Susumu Fukita, Risako Sakai

Abstract:

Lifestyle-related diseases develop from the long-term accumulation of health consequences from a poor lifestyle. Thus, schoolchildren, who have not accumulated long-term lifestyle habits, are believed to be at a lower risk for lifestyle-related diseases. However, schoolchildren rarely receive blood tests unless they are under treatment for a serious disease; without such data on their blood, the impacts of their young lifestyle could not be known. Blood data from physical measurements can help in the implementation of more effective health education. Therefore, we examined the correlation between body mass index (BMI) and blood sugar/serum lipid (BS/SL) levels. From 2014 to 2016, we measured the blood data of fourth-grade students living in a city in Japan. The present study reported on the results of 281 fourth-grade boys only (80.3% of total). We analyzed their BS/SL levels by comparing the blood data against the criteria of the National Center for Child Health and Development in Japan. Next, we examined the correlation between BMI and BS/SL levels. IBM SPSS Statistics for Windows, Version 25 was used for analysis. A total of 69 boys (24.6%) were within the normal range for BMI (18.5–24), whereas 193 (71.5%) and 8 boys (2.8%) had lower and higher BMI, respectively. Regarding BS levels, 280 boys were within the normal range (70–90 mg/dl); 1 boy reported a higher value. All the boys were within the normal range for glycated Hemoglobin (HbA1c) (4.6–6.2%). Regarding SL levels, 271 boys were within the normal range (125–230 mg/dl) for total cholesterol (TC), whereas 5 boys (1.8%) had lower and 5 boys (1.8%) had higher levels. A total of 243 boys (92.7%) were within the normal range (36-138mg/dL) for triglycerides (TG), whereas 19 boys (7.3%) had lower and 19 boys (7.3%) had higher levels. Regarding high-density lipoprotein cholesterol (HDL-C), 276 boys (98.2%) were within the normal range (40-mg/dl), whereas 5 boys (1.8%) reported lower values. All but one boy (280, 99.6%) were within the normal range (-170 mg/dl) for low-density lipoprotein cholesterol (LDL-C); the exception (0.4%) had a higher level. BMI and BS didn’t show a correlation. BMI and HbA1c were moderately positively correlated (r = 0.139, p=0.019). We also observed moderate positive correlations between BMI and TG (r = 0.328, p < 0.01), TC (r=0.239, p< 0.01), LDL-C (r = 0.324, p < 0.01), respectively. BMI and HDL-C were low correlated (r = -0.185, p = 0.002). Most of the boys were within the normal range for BS/SL levels. However, some boys exceeded the normal TG range. Fourth graders with a high TG may develop a lifestyle-related disease in the future. Given its relation to TG, food habits should be improved in this group. Our findings suggested a positive correlation between BMI and BS/SL levels. Fourth-grade schoolboys with a high BMI may be at high risk for developing lifestyle-related diseases. Lifestyle improvement may be recommended to lower the BS/SL levels in this group.

Keywords: blood sugar level, lifestyle-related diseases, school students, serum lipid level

Procedia PDF Downloads 122
6563 Effect of Dietary Supplementation of Allium Hookeri Root and Processed Sulfur on the Growth Performance of Guinea Pigs

Authors: Nayeon, Lee, Won-Young, Cho, Hyun Joo, Jang, Chi-Ho, Lee

Abstract:

This study investigated the effects of the dietary supplementation of the Allium hookeri root, and processed sulfur, on the growth performance of guinea pigs. The guinea pigs were fed a control diet (CON), as well as the control diet including 1% freeze-dried Allium hookeri root (AH), or 0.1% processed sulfur (S), or including both the freeze-dried Allium hookeri root and the processed sulfur (AHS). The weight of perirenal adipose tissue (PAT) and the epididymal adipose tissue (EAT) in the AH were significantly lower than CON (p < 0.05). The serum cholesterols levels of the AH and the AHS were significantly lower than the S (p < 0.05). While the total saturated fatty acid content in the serum of the AH and AHS groups showed a tendency to decrease, the total monounsaturated fatty acid increased. The results of this study suggested that dietary consumption of Allium hookeri root may help to decrease fat accumulation, lower serum cholesterol levels, and control serum free fatty acid contents in the guinea pigs.

Keywords: Allium hookeri, dietary supplementation, growth performance, processed sulfur, Guinea pig

Procedia PDF Downloads 249
6562 Comparative Policy Analysis on Agropolitan Territorial Development in Rural Area: A Study Case in Bojonegoro Regency, Indonesia

Authors: Fatihin Khoirul, Muhammad Muqorrobin Ist

Abstract:

Bojonegoro Regency is one of the districts that use the concept Agropolitan as the Territorial Development Policy. Three sub-district designated as Area Development District of Agropolitan are Kapas, Dander, and Kalitidu or commonly called KADEKA. Current policy has been shown results, but there was an inequality of results in some areas. One of them occurred in the Ngringinrejo village with the main commodities is Starfruit and Wedi village with the main commodities is Salak fruit. Therefore, a comparative study is used to search for causal factors of inequality result of the policy by using the 5 aspects compared, namely: (1) Management Development Agropolitan; (2) Physical Condition agropolitan Region; (3) Implementing Agency at the Village Level; (4) Village Government Support; and (5) Community support. Based on the discussion of qualitative analysis, it was found that five aspects have their respective roles in creating inequality of outcomes that occur in both villages. But beyond that, there are conditions where the two villages experienced the same condition that is when the initial implementation of the policy. The condition is referred to as 'the phenomenon of price trap.' The condition is caused by lower commodity prices, causing the village government's commitment in implementing policies too low, followed by public awareness in support of the policy is also low, so care for commodities is also low, and the quality is too low lead and eventually back causing low price. However, the difference is that the village Ngringinrejo able to get out of this condition with 'the new culture of administration' at the end of 2013. While the conditions in the village of Wedi compounded by not respected request assistance by the irrigation district.

Keywords: comparative policy analysis, qualitative comparative, inequallity, price trap, new culture of administration

Procedia PDF Downloads 262
6561 Electromyography Activity of the Lower Limb Muscles during Prostration and Squat Exercise

Authors: M. K. Mohd Safee, W. A. B. Wan Abas, F. Ibrahim, N. A. Abu Osman, N. A. Abdul Malik

Abstract:

This paper investigates the activity of the rectus femoris (RF) and biceps femoris (BF) in healthy subjects during salat (prostration) and specific exercise (squat exercise) using electromyography (EMG). A group of undergraduates aged between 19 to 25 years voluntarily participated in this study. The myoelectric activity of the muscles were recorded and analyzed. The finding indicated that there were contractions of the muscles during the salat and exercise with almost same EMG’s level. From the result, Wilcoxon’s Rank Sum test showed significant difference between prostration and squat exercise (p < 0.05) but the differences was very small; RF (8.63% MVC) and BF (11.43% MVC). Therefore, salat may be useful in strengthening exercise and also in rehabilitation programs for lower limb activities. This pilot study conducted initial research into the bio mechanical responses of human muscles in various positions of salat.

Keywords: electromyography, exercise, muscle, salat

Procedia PDF Downloads 688
6560 Imaging of Underground Targets with an Improved Back-Projection Algorithm

Authors: Alireza Akbari, Gelareh Babaee Khou

Abstract:

Ground Penetrating Radar (GPR) is an important nondestructive remote sensing tool that has been used in both military and civilian fields. Recently, GPR imaging has attracted lots of attention in detection of subsurface shallow small targets such as landmines and unexploded ordnance and also imaging behind the wall for security applications. For the monostatic arrangement in the space-time GPR image, a single point target appears as a hyperbolic curve because of the different trip times of the EM wave when the radar moves along a synthetic aperture and collects reflectivity of the subsurface targets. With this hyperbolic curve, the resolution along the synthetic aperture direction shows undesired low resolution features owing to the tails of hyperbola. However, highly accurate information about the size, electromagnetic (EM) reflectivity, and depth of the buried objects is essential in most GPR applications. Therefore hyperbolic curve behavior in the space-time GPR image is often willing to be transformed to a focused pattern showing the object's true location and size together with its EM scattering. The common goal in a typical GPR image is to display the information of the spatial location and the reflectivity of an underground object. Therefore, the main challenge of GPR imaging technique is to devise an image reconstruction algorithm that provides high resolution and good suppression of strong artifacts and noise. In this paper, at first, the standard back-projection (BP) algorithm that was adapted to GPR imaging applications used for the image reconstruction. The standard BP algorithm was limited with against strong noise and a lot of artifacts, which have adverse effects on the following work like detection targets. Thus, an improved BP is based on cross-correlation between the receiving signals proposed for decreasing noises and suppression artifacts. To improve the quality of the results of proposed BP imaging algorithm, a weight factor was designed for each point in region imaging. Compared to a standard BP algorithm scheme, the improved algorithm produces images of higher quality and resolution. This proposed improved BP algorithm was applied on the simulation and the real GPR data and the results showed that the proposed improved BP imaging algorithm has a superior suppression artifacts and produces images with high quality and resolution. In order to quantitatively describe the imaging results on the effect of artifact suppression, focusing parameter was evaluated.

Keywords: algorithm, back-projection, GPR, remote sensing

Procedia PDF Downloads 429
6559 Parenting a Child with Mental Health Problems: The Role of Self-compassion

Authors: Vered Shenaar-Golan, Nava Wald, Uri Yatzkar

Abstract:

Background: Parenting children with mental health problems poses multiple challenges, including coping with difficult behavior and negative child emotions. The impact on parents includes financial strain, negative social stigma, and negative feelings of guilt or blame, resulting in significant stress and lower levels of well-being. Given findings that self-compassion plays a significant role in reducing stress and improving well-being, the current study examined the role of self-compassion in the experience of parents raising a child with mental health problems. The study tested (1) whether child behavioral/emotional problem severity is associated with higher parental stress and lower parental well-being; (2) whether self-compassion is associated with lower parental stress and higher parental well-being; and (3) whether self-compassion is a stronger predictor of parental stress and well-being than child behavioral/emotional problem severity. Methods: Three hundred and six mothers and two hundred and fifty-six fathers of children attending a hospital child and adolescent psychiatric center were assessed at admission. Consenting parents completed four questionnaires: Child Strength and Difficulty – parent version, Self-compassion, Parent Feeling Inventory, and Well-Being. Results: Child behavioral/emotional problem severity was associated with higher parental stress and lower parental well-being, and self-compassion was a stronger predictor of parental stress and well-being levels than child behavioral/emotional problem severity. For children with internalizing but not externalizing behavioral/emotional problems, parental self-compassion was the only predictor of parental well-being beyond the severity of child behavioral/emotional problems. Conclusions: Cultivating self-compassion is important in reducing parental stress and increasing parental well-being, particularly with internalizing presentations, and should be considered when designing therapeutic interventions for parents.

Keywords: parenting children with mental health problems, self-compassion, parental stress, feelings, well-being

Procedia PDF Downloads 57
6558 Growth Patterns of Pyrite Crystals Studied by Electron Back Scatter Diffraction (EBSD)

Authors: Kirsten Techmer, Jan-Erik Rybak, Simon Rudolph

Abstract:

Natural formed pyrites (FeS2) are frequent sulfides in sedimentary and metamorphic rocks. Growth textures of idiomorphic pyrite assemblages reflect the conditions during their formation in the geologic sequence, furtheron the local texture analyses of the growth patterns of pyrite assemblages by EBSD reveal the possibility to resolve the growth conditions during the formation of pyrite at the micron scale. The spatial resolution of local texture measurements in the Scanning Electron Microscope used can be in the nanomete scale. Orientation contrasts resulting from domains of smaller misorientations within larger pyrite crystals can be resolved as well. The electron optical studies have been carried out in a Field-Emission Scanning Electron Microscope (FEI Quanta 200) equipped with a CCD camera to study the orientation contrasts along the surfaces of pyrite. Idiomorphic cubic single crystals of pyrite, polycrystalline assemblages of pyrite, spherically grown spheres of pyrite as well as pyrite-bearing ammonites have been studied by EBSD in the Scanning Electron Microscope. Samples were chosen to show no or minor secondary deformation and an idiomorphic 3D crystal habit, so the local textures of pyrite result mainly from growth and minor from deformation. The samples studied derived from Navajun (Spain), Chalchidiki (Greece), Thüringen (Germany) and Unterkliem (Austria). Chemical analyses by EDAX show pyrite with minor inhomogeneities e.g., single crystals of galena and chalcopyrite along the grain boundaries of larger pyrite crystals. Intergrowth between marcasite and pyrite can be detected in one sample. Pyrite may form intense growth twinning lamellae on {011}. Twinning, e.g., contact twinning is abundant within the crystals studied and the individual twinning lamellaes can be resolved by EBSD. The ammonites studied show a replacement of the shale by newly formed pyrite resulting in an intense intergrowth of calcite and pyrite. EBSD measurements indicate a polycrystalline microfabric of both minerals, still reflecting primary surface structures of the ammonites e.g, the Septen. Discs of pyrite (“pyrite dollar”) as well as pyrite framboids show growth patterns comprising a typical microfabric. EBSD studies reveal an equigranular matrix in the inner part of the discs of pyrite and a fiber growth with larger misorientations in the outer regions between the individual segments. This typical microfabric derived from a formation of pyrite crystals starting at a higher nucleation rate and followed by directional crystal growth. EBSD studies show, that the growth texture of pyrite in the samples studied reveals a correlation between nucleation rate and following growth rate of the pyrites, thus leading to the characteristic crystal habits. Preferential directional growth at lower nucleation rates may lead to the formation of 3D framboids of pyrite. Crystallographic misorientations between the individual fibers are similar. In ammonites studied, primary anisotropies of the substrates like e.g., ammonitic sutures, influence the nucleation, crystal growth and habit of the newly formed pyrites along the surfaces.

Keywords: Electron Back Scatter Diffraction (EBSD), growth pattern, Fe-sulfides (pyrite), texture analyses

Procedia PDF Downloads 273
6557 Studies on the Characterization and Machinability of Duplex Stainless Steel 2205 during Dry Turning

Authors: Gaurav D. Sonawane, Vikas G. Sargade

Abstract:

The present investigation is a study of the effect of advanced Physical Vapor Deposition (PVD) coatings on cutting temperature residual stresses and surface roughness during Duplex Stainless Steel (DSS) 2205 turning. Austenite stabilizers like nickel, manganese, and molybdenum reduced the cost of DSS. Surface Integrity (SI) plays an important role in determining corrosion resistance and fatigue life. Resistance to various types of corrosion makes DSS suitable for applications with critical environments like Heat exchangers, Desalination plants, Seawater pipes and Marine components. However, lower thermal conductivity, poor chip control and non-uniform tool wear make DSS very difficult to machine. Cemented carbide tools (M grade) were used to turn DSS in a dry environment. AlTiN and AlTiCrN coatings were deposited using advanced PVD High Pulse Impulse Magnetron Sputtering (HiPIMS) technique. Experiments were conducted with cutting speed of 100 m/min, 140 m/min and 180 m/min. A constant feed and depth of cut of 0.18 mm/rev and 0.8 mm were used, respectively. AlTiCrN coated tools followed by AlTiN coated tools outperformed uncoated tools due to properties like lower thermal conductivity, higher adhesion strength and hardness. Residual stresses were found to be compressive for all the tools used for dry turning, increasing the fatigue life of the machined component. Higher cutting temperatures were observed for coated tools due to its lower thermal conductivity, which results in very less tool wear than uncoated tools. Surface roughness with uncoated tools was found to be three times higher than coated tools due to lower coefficient of friction of coating used.

Keywords: cutting temperature, DSS2205, dry turning, HiPIMS, surface integrity

Procedia PDF Downloads 111
6556 IntelliCane: A Cane System for Individuals with Lower-Limb Mobility and Functional Impairments

Authors: Adrian Bostan, Nicolae Tapus, Adriana Tapus

Abstract:

The purpose of this research paper is to study and develop a system that is able to help identify problems and improve human rehabilitation after traumatic injuries. Traumatic injuries in human’s lower limbs can occur over a life time and can have serious side effects if they are not treated correctly. In this paper, we developed an intelligent cane (IntelliCane) so as to help individuals in their rehabilitation process and provide feedback to the users. The first stage of the paper involves an analysis of the existing systems on the market and what can be improved. The second stage presents the design of the system. The third part, which is still under development is the validation of the system in real world setups with people in need. This paper presents mainly stages one and two.

Keywords: IntelliCane, 3D printing, microprocessor, weight measurement, rehabilitation tool

Procedia PDF Downloads 223
6555 A Study of Anthropometric Correlation between Upper and Lower Limb Dimensions in Sudanese Population

Authors: Altayeb Abdalla Ahmed

Abstract:

Skeletal phenotype is a product of a balanced interaction between genetics and environmental factors throughout different life stages. Therefore, interlimb proportions are variable between populations. Although interlimb proportion indices have been used in anthropology in assessing the influence of various environmental factors on limbs, an extensive literature review revealed that there is a paucity of published research assessing interlimb part correlations and possibility of reconstruction. Hence, this study aims to assess the relationships between upper and lower limb parts and develop regression formulae to reconstruct the parts from one another. The left upper arm length, ulnar length, wrist breadth, hand length, hand breadth, tibial length, bimalleolar breadth, foot length, and foot breadth of 376 right-handed subjects, comprising 187 males and 189 females (aged 25-35 years), were measured. Initially, the data were analyzed using basic univariate analysis and independent t-tests; then sex-specific simple and multiple linear regression models were used to estimate upper limb parts from lower limb parts and vice-versa. The results of this study indicated significant sexual dimorphism for all variables. The results indicated a significant correlation between the upper and lower limbs parts (p < 0.01). Linear and multiple (stepwise) regression equations were developed to reconstruct the limb parts in the presence of a single or multiple dimension(s) from the other limb. Multiple stepwise regression equations generated better reconstructions than simple equations. These results are significant in forensics as it can aid in identification of multiple isolated limb parts particularly during mass disasters and criminal dismemberment. Although a DNA analysis is the most reliable tool for identification, its usage has multiple limitations in undeveloped countries, e.g., cost, facility availability, and trained personnel. Furthermore, it has important implication in plastic and orthopedic reconstructive surgeries. This study is the only reported study assessing the correlation and prediction capabilities between many of the upper and lower dimensions. The present study demonstrates a significant correlation between the interlimb parts in both sexes, which indicates a possibility to reconstruction using regression equations.

Keywords: anthropometry, correlation, limb, Sudanese

Procedia PDF Downloads 274