Search results for: Valerie Chavez
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 73

Search results for: Valerie Chavez

73 Non-Linear Causality Inference Using BAMLSS and Bi-CAM in Finance

Authors: Flora Babongo, Valerie Chavez

Abstract:

Inferring causality from observational data is one of the fundamental subjects, especially in quantitative finance. So far most of the papers analyze additive noise models with either linearity, nonlinearity or Gaussian noise. We fill in the gap by providing a nonlinear and non-gaussian causal multiplicative noise model that aims to distinguish the cause from the effect using a two steps method based on Bayesian additive models for location, scale and shape (BAMLSS) and on causal additive models (CAM). We have tested our method on simulated and real data and we reached an accuracy of 0.86 on average. As real data, we considered the causality between financial indices such as S&P 500, Nasdaq, CAC 40 and Nikkei, and companies' log-returns. Our results can be useful in inferring causality when the data is heteroskedastic or non-injective.

Keywords: causal inference, DAGs, BAMLSS, financial index

Procedia PDF Downloads 150
72 Low Temperature Solution Processed Solar Cell Based on ITO/PbS/PbS:Bi3+ Heterojunction

Authors: M. Chavez, H. Juarez, M. Pacio, O. Portillo

Abstract:

PbS chemical bath heterojunction sollar cells have shown significant improvements in performance. Here we demonstrate a solar cell based on the heterojunction formed between PbS layer and PbS:Bi3+ thin films that are deposited via solution process at 40°C. The device achieve an current density of 4 mA/cm2. The simple and low-cost deposition method of PbS:Bi3+ films is promising for the fabrication.

Keywords: PbS doped, Bismuth, solar cell, thin films

Procedia PDF Downloads 552
71 A New Gateway for Rheumatoid Arthritis: COXIBs with a Safety Cardiovascular Profile

Authors: Malvina Hoxha, Valerie Capra, Carola Buccellati, Angelo Sala, Clara Cena, Roberta Fruttero, Massimo Bertinaria, G. Enrico Rovati

Abstract:

Today COXIBs are used in the treatment of arthritis and many other painful conditions in selected patients with high gastrointestinal risk and low CV risk. Previously we found a new mechanism of action of a traditional NSAID (diclofenac) and a COXIB (lumiracoxib) that possess weak competitive antagonism at the TP receptor. We hypothesize that modifying the structure of a known specific inhibitor of cyclooxygenase-2 (COXIB), so that it becomes also a more potent thromboxane antagonist will preserve the anti-inflammatory and gastrointestinal safety typical of COXIBs and prevent the cardiovascular risk associated with long term therapy.

Keywords: cyclooxygenase, inflammation, lumiracoxib, thromboxane A2

Procedia PDF Downloads 300
70 Solar Cell Using Chemical Bath Deposited PbS:Bi3+ Films as Electron Collecting Layer

Authors: Melissa Chavez Portillo, Mauricio Pacio Castillo, Hector Juarez Santiesteban, Oscar Portillo Moreno

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Chemical bath deposited PbS:Bi3+ as an electron collection layer is introduced between the silicon wafer and the Ag electrode the performance of the PbS heterojunction thin film solar thin film solar cells with 1 cm2 active area. We employed Bi-doping to transform it into an n-type semiconductor. The experimental results reveal that the cell response parameters depend critically on the deposition procedures in terms of bath temperature, deposition time. The device achieves an open-circuit voltage of 0.4 V. The simple and low-cost deposition method of PbS:Bi3+ films is promising for the fabrication.

Keywords: Bi doping, PbS, thin films, solar cell

Procedia PDF Downloads 513
69 Comparison of the Seismic Response of Planar Regular and Irregular Steel Frames

Authors: Robespierre Chavez, Eden Bojorquez, Alfredo Reyes-Salazar

Abstract:

This study compares the seismic response of regular and vertically irregular steel frames determined by nonlinear time history analysis and by using several sets of earthquake records, which are divided in two categories: The first category having 20 stiff-soil ground motion records obtained from the NGA database, and the second category having 30 soft-soil ground motions recorded in the Lake Zone of Mexico City and exhibiting a dominant period (Ts) of two seconds. The steel frames in both format regular and irregular were designed according to the Mexico City Seismic Design Provisions (MCSDP). The effects of irregularity throught the height on the maximum interstory drifts are estimated.

Keywords: irregular steel frames, maximum interstory drifts, seismic response, seismic records

Procedia PDF Downloads 326
68 Smart Technology for Hygrothermal Performance of Low Carbon Material Using an Artificial Neural Network Model

Authors: Manal Bouasria, Mohammed-Hichem Benzaama, Valérie Pralong, Yassine El Mendili

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Reducing the quantity of cement in cementitious composites can help to reduce the environmental effect of construction materials. By-products such as ferronickel slags (FNS), fly ash (FA), and Crepidula fornicata (CR) are promising options for cement replacement. In this work, we investigated the relevance of substituting cement with FNS-CR and FA-CR on the mechanical properties of mortar and on the thermal properties of concrete. Foraging intervals ranging from 2 to 28 days, the mechanical properties are obtained by 3-point bending and compression tests. The chosen mix is used to construct a prototype in order to study the material’s hygrothermal performance. The data collected by the sensors placed on the prototype was utilized to build an artificial neural network.

Keywords: artificial neural network, cement, circular economy, concrete, by products

Procedia PDF Downloads 113
67 Quartz Crystal Microbalance Holder Design for On-Line Sensing in Liquid Applications

Authors: M. A. Amer, J. A. Chávez, M. J. García-Hernández, J. Salazar, A. Turó

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In this paper, the design of a QCM sensor for liquid media measurements in vertical position is described. A rugged and low-cost proof holder has been designed, the cost of which is significantly lower than those of traditional commercial holders. The crystal is not replaceable but it can be easily cleaned. Its small volume permits to be used by dipping it in the liquid with the desired location and orientation. The developed design has been experimentally validated by measuring changes in the resonance frequency and resistance of the QCM sensor immersed vertically in different calibrated aqueous glycerol solutions. The obtained results show a great agreement with the Kanazawa theoretical expression. Consequently, the designed QCM sensor would be appropriate for sensing applications in liquids, and might take part of a future on-line multichannel low-cost QCM-based measurement system.

Keywords: holder design, liquid-media measurements, multi-channel measurements, QCM

Procedia PDF Downloads 381
66 Usy-Cui Zeolite: An Efficient and Reusable Catalyst for Derivatives Indole Synthesis

Authors: Hassina Harkat, Samiha Taybe, Salima Loucif, Valérie Beneteau, Patrick Pale

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Indole and its derivatives have attracted great interest because of their importance in the synthetic organic and medicinal chemistry. They are widely used as anti hypertension, anti tubercular, anticancer activity, antiviral, Alzheimer's disease, antioxidant properties, and free radical induced lipid peroxidation. Many drugs and natural products contain indole moiety, such as the vinca alkaloids, fungal metabolites and marine natural products. Generally applicable synthetic methods for indole moiety involve ring closure to form the pyrrole. Indole derivatives can also be accessed by further functionalization of the indole nucleus. Therefore we report a mild and efficient protocol for the synthesis of analogues of indole catalyzed via zeolithe USY doped with CuI under solvent-free conditions.

Keywords: indole, zeolithe, USY-CuI, heterogeneous catalysis

Procedia PDF Downloads 584
65 Structural and Optoelectronic Properties of Monovalent Cation Doping PbS Thin Films

Authors: Melissa Chavez Portillo, Hector Juarez Santiesteban, Mauricio Pacio Castillo, Oscar Portillo Moreno

Abstract:

Nanocrystalline Li-doped PbS thin films have been deposited by chemical bath deposition technique. The goal of this work is to study the modification of the optoelectronic and structural properties of Lithium incorporation. The increase of Li doping in PbS thin films leads to an increase of band gap in the range of 1.4-2.3, consequently, quantum size effect becomes pronounced in the Li-doped PbS films, which lead to a significant enhancement in the optical band gap. Doping shows influence in the film growth and results in a reduction of crystallite size from 30 to 14 nm. The refractive index was calculated and a relationship with dielectric constant was investigated. The dc conductivities of Li-doped and undoped samples were measured in the temperature range 290-340K, the conductivity increase with increase of Lithium content in the PbS films.

Keywords: doping, quantum confinement, optical band gap, PbS

Procedia PDF Downloads 382
64 Enhancing the Safety Climate and Reducing Violence against Staff in Closed Hospital Wards

Authors: Valerie Isaak

Abstract:

This study examines the effectiveness of an intervention program aimed at enhancing a unit-level safety climate as a way to minimize the risk of employees being injured by patient violence. The intervention program conducted in maximum security units in one of the psychiatric hospitals in Israel included a three day workshop. Safety climate was examined before and after the implementation of the intervention. We also collected data regarding incidents involving patient violence. Six months after the intervention a significant improvement in employees’ perceptions regarding management’s commitment to safety were found as well as a marginally significant improvement in communication concerning safety issues. Our research shows that an intervention program aimed at enhancing a safety climate is associated with a decrease in the number of aggressive incidents. We conclude that such an intervention program is likely to return the sense of safety and reduce the scope of violence.

Keywords: violence, intervention, safety climate, performance, public sector

Procedia PDF Downloads 352
63 Fecal Immunochemical Testing to Deter Colon Cancer

Authors: Valerie A. Conrade

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Introduction: A large body of literature suggests patients who complete fecal immunochemical testing (FIT) kits are likely to identify colorectal cancer sooner than those who do not complete FIT kits. Background: Patients who do not participate in preventative measures such as the FIT kit are at a higher risk of colorectal cancer growing unnoticed. The objective was to see if the method the principal investigator (PI) uses to educate clinical staff on the importance of FIT kit administration provides an increased amount of FIT kit dissemination to patients post clinical education. Methodologies: Data collection via manual tallies took place before and after the clinical staff was educated on the importance of FIT kits. Results: The results showed an increase in FIT kit dissemination post clinical staff education. Through enhanced instruction to the clinical staff regarding the importance of FIT kits, expanding their knowledge on preventative measures to detect colorectal cancer positively impacted nurses and, in turn, their patients.

Keywords: colon cancer, education, fecal immunochemical testing, nursing

Procedia PDF Downloads 134
62 Evaluation Synthesis of Private Sector Engagement in International Development

Authors: Valerie Habbel, Magdalena Orth, Johanna Richter, Steffen Schimko

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Cooperation between development actors and the private sector is becoming increasingly important, as it is expected to mobilize additional resources to achieve the Sustainable Development Goals (SDGs), among other things. However, whether the goals of cooperation are achieved has so far only been explored in evaluations and studies of individual projects and instruments. The evaluation synthesis attempts to close this gap by systematically analyzing existing evidence (evaluations and academic studies) from national and international development cooperation on private sector engagement. Overall, the evaluations and studies considered report mainly positive effects on investors and donors, intermediaries, partner countries, and target groups. However, various analyses, including on the quality of the evaluations, point to a positive bias in the results. The evaluation synthesis makes recommendations on the definition of indicators, the measurement and evaluation of impacts and additionality, knowledge management, and the consideration of transaction costs in cooperation with private actors.

Keywords: evaluation synthesis, private sector engagement, international development, sustainable development

Procedia PDF Downloads 208
61 Character Strengths and Military Leadership

Authors: Lobna Cherif, Valerie Wood

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The importance of both character and resilience for military members has been emphasized at the highest levels of military leadership. Initial research suggests that the presence of character strengths might be relevant in predicting success and well-being for some military populations (e.g., recruits). In this presentation, we will first review our research investigating the perceived importance of character strengths for Canadian military cadet (N = 134) success, the top strengths endorsed by cadets, and, in a subset of cadets (n = 94), the relationships among core strengths and resilience. Participants first completed a survey comprised of a resilience measure and demographic items, then one month later completed a Values in Action (VIA) character strengths profile, questions related to character strengths (their personal top-five character strengths, and strengths they believed were important for military-related stressors and leadership, academic success, resilience, and completion of the military challenge). Findings indicated that military cadets consider (among others), perseverance, judgment, and teamwork to be most critical for bouncing back from stressors. However, the most frequently endorsed strengths that characterized cadets were bravery, honesty, and perseverance. Finally, perseverance, bravery, and humor were positively correlated with cadet resilience, while endorsement of love was negatively correlated with resilience.

Keywords: character strengths, leadership, positive psychology, resilience

Procedia PDF Downloads 188
60 The Shrinking of the Pink Wave and the Rise of the Right-Wing in Latin America

Authors: B. M. Moda, L. F. Secco

Abstract:

Through free and fair elections and others less democratic processes, Latin America has been gradually turning into a right-wing political region. In order to understand these recent changes, this paper aims to discuss the origin and the traits of the pink wave in the subcontinent, the reasons for its current rollback and future projections for left-wing in the region. The methodology used in this paper will be descriptive and analytical combined with secondary sources mainly from the social and political sciences fields. The canons of the Washington Consensus was implemented by the majority of the Latin American governments in the 80s and 90s under the social democratic and right-wing parties. The neoliberal agenda caused political, social and economic dissatisfaction bursting into a new political configuration for the region. It started in 1998 when Hugo Chávez took the office in Venezuela through the Fifth Republic Movement under the socialist flag. From there on, Latin America was swiped by the so-called ‘pink wave’, term adopted to define the rising of self-designated left-wing or center-left parties with a progressive agenda. After Venezuela, countries like Chile, Brazil, Argentina, Uruguay, Bolivia, Equator, Nicaragua, Paraguay, El Salvador and Peru got into the pink wave. The success of these governments was due a post-neoliberal agenda focused on cash transfers programs, increasing of public spending, and the straightening of national market. The discontinuation of the preference for the left-wing started in 2012 with the coup against Fernando Lugo in Paraguay. In 2015, the chavismo in Venezuela lost the majority of the legislative seats. In 2016, an impeachment removed the Brazilian president Dilma Rousself from office who was replaced by the center-right vice-president Michel Temer. In the same year, Mauricio Macri representing the right-wing party Proposta Republicana was elected in Argentina. In 2016 center-right and liberal, Pedro Pablo Kuczynski was elected in Peru. In 2017, Sebastián Piñera was elected in Chile through the center-right party Renovación Nacional. The pink wave current rollback points towards some findings that can be arranged in two fields. Economically, the 2008 financial crisis affected the majority of the Latin American countries and the left-wing economic policies along with the end of the raw materials boom and the subsequent shrinking of economic performance opened a flank for popular dissatisfaction. In Venezuela, the 2014 oil crisis reduced the revenues for the State in more than 50% dropping social spending, creating an inflationary spiral, and consequently loss of popular support. Politically, the death of Hugo Chavez in 2013 weakened the ‘socialism of the twenty first century’ ideal, which was followed by the death of Fidel Castro, the last bastion of communism in the subcontinent. In addition, several cases of corruption revealed during the pink wave governments made the traditional politics unpopular. These issues challenge the left-wing to develop a future agenda based on innovation of its economic program, improve its legal and political compliance practices, and to regroup its electoral forces amid the social movements that supported its ascension back in the early 2000s.

Keywords: Latin America, political parties, left-wing, right-wing, pink wave

Procedia PDF Downloads 239
59 Using Differentiation Instruction to Create a Personalized Experience

Authors: Valerie Yocco Rossi

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Objective: The author will share why differentiation is necessary for all classrooms as well as strategies for differentiating content, process, and product. Through learning how to differentiate, teachers will be able to create activities and assessments to meet the abilities, readiness levels, and interests of all learners. Content and Purpose: This work will focus on how to create a learning experience for students that recognizes their different interests, abilities, and readiness levels by differentiating content, process, and product. Likewise, the best learning environments allow for choice. Choice boards allow students to select tasks based on interests. There can be challenging and basic tasks to meet the needs of various abilities. Equally, rubrics allow for personalized and differentiated assessments based on readiness levels and cognitive abilities. The principals of DI help to create a classroom where all students are learning to the best of their abilities. Outcomes: After reviewing the work, readers will be able to (1) identify the benefits of differentiated instruction; (2) convert traditional learning activities to differentiated ones; (3) differentiate, writing-based assessments.

Keywords: differentiation, personalized learning, design, instructional strategies

Procedia PDF Downloads 69
58 Automatic Product Identification Based on Deep-Learning Theory in an Assembly Line

Authors: Fidel Lòpez Saca, Carlos Avilés-Cruz, Miguel Magos-Rivera, José Antonio Lara-Chávez

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Automated object recognition and identification systems are widely used throughout the world, particularly in assembly lines, where they perform quality control and automatic part selection tasks. This article presents the design and implementation of an object recognition system in an assembly line. The proposed shapes-color recognition system is based on deep learning theory in a specially designed convolutional network architecture. The used methodology involve stages such as: image capturing, color filtering, location of object mass centers, horizontal and vertical object boundaries, and object clipping. Once the objects are cut out, they are sent to a convolutional neural network, which automatically identifies the type of figure. The identification system works in real-time. The implementation was done on a Raspberry Pi 3 system and on a Jetson-Nano device. The proposal is used in an assembly course of bachelor’s degree in industrial engineering. The results presented include studying the efficiency of the recognition and processing time.

Keywords: deep-learning, image classification, image identification, industrial engineering.

Procedia PDF Downloads 159
57 U11 Functionalised Luminescent Gold Nanoclusters for Pancreatic Tumor Cells Labelling

Authors: Regina M. Chiechio, Rémi Leguevél, Helene Solhi, Marie Madeleine Gueguen, Stephanie Dutertre, Xavier, Jean-Pierre Bazureau, Olivier Mignen, Pascale Even-Hernandez, Paolo Musumeci, Maria Jose Lo Faro, Valerie Marchi

Abstract:

Thanks to their ultra-small size, high electron density, and low toxicity, gold nanoclusters (Au NCs) have unique photoelectrochemical and luminescence properties that make them very interesting for diagnosis bio-imaging and theranostics. These applications require control of their delivery and interaction with cells; for this reason, the surface chemistry of Au NCs is essential to determine their interaction with the targeted biological objects. Here we demonstrate their ability as markers of pancreatic tumor cells. By functionalizing the surface of the NCs with a recognition peptite (U11), the nanostructures are able to preferentially bind to pancreatic cancer cells via a receptor (uPAR) overexpressed by these cells. Furthermore, the NCs can mark even the nucleus without the need of fixing the cells. These nanostructures can therefore be used as a non-toxic, multivalent luminescent platform, capable of selectively recognizing tumor cells for bioimaging, drug delivery, and radiosensitization.

Keywords: gold nanoclusters, luminescence, biomarkers, pancreatic cancer, biomedical applications, bioimaging, fluorescent probes, drug delivery

Procedia PDF Downloads 149
56 The Effects of Normal Aging on Reasoning Ability: A Dual-Process Approach

Authors: Jamie A. Prowse Turner, Jamie I. D. Campbell, Valerie A. Thompson

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The objective of the current research was to use a dual-process theory framework to explain these age-related differences in reasoning. Seventy-two older (M = 80.0 years) and 72 younger (M = 24.6 years) adults were given a variety of reasoning tests (i.e., a syllogistic task, base rate task, the Cognitive Reflection Test, and a perspective manipulation), as well as independent tests of capacity (working memory, processing speed, and inhibition), thinking styles, and metacognitive ability, to account for these age-related differences. It was revealed that age-related differences were limited to problems that required Type 2 processing and were related to differences in cognitive capacity, individual difference factors, and strategy choice. Furthermore, older adults’ performance can be improved by reasoning from another’s’ perspective and cannot, at this time, be explained by metacognitive differences between young and older adults. All of these findings fit well within a dual-process theory of reasoning, which provides an integrative framework accounting for previous findings and the findings presented in the current manuscript.

Keywords: aging, dual-process theory, performance, reasoning ability

Procedia PDF Downloads 190
55 A New Fuzzy Fractional Order Model of Transmission of Covid-19 With Quarantine Class

Authors: Asma Hanif, A. I. K. Butt, Shabir Ahmad, Rahim Ud Din, Mustafa Inc

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This paper is devoted to a study of the fuzzy fractional mathematical model reviewing the transmission dynamics of the infectious disease Covid-19. The proposed dynamical model consists of susceptible, exposed, symptomatic, asymptomatic, quarantine, hospitalized and recovered compartments. In this study, we deal with the fuzzy fractional model defined in Caputo’s sense. We show the positivity of state variables that all the state variables that represent different compartments of the model are positive. Using Gronwall inequality, we show that the solution of the model is bounded. Using the notion of the next-generation matrix, we find the basic reproduction number of the model. We demonstrate the local and global stability of the equilibrium point by using the concept of Castillo-Chavez and Lyapunov theory with the Lasalle invariant principle, respectively. We present the results that reveal the existence and uniqueness of the solution of the considered model through the fixed point theorem of Schauder and Banach. Using the fuzzy hybrid Laplace method, we acquire the approximate solution of the proposed model. The results are graphically presented via MATLAB-17.

Keywords: Caputo fractional derivative, existence and uniqueness, gronwall inequality, Lyapunov theory

Procedia PDF Downloads 104
54 Some Accuracy Related Aspects in Two-Fluid Hydrodynamic Sub-Grid Modeling of Gas-Solid Riser Flows

Authors: Joseph Mouallem, Seyed Reza Amini Niaki, Norman Chavez-Cussy, Christian Costa Milioli, Fernando Eduardo Milioli

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Sub-grid closures for filtered two-fluid models (fTFM) useful in large scale simulations (LSS) of riser flows can be derived from highly resolved simulations (HRS) with microscopic two-fluid modeling (mTFM). Accurate sub-grid closures require accurate mTFM formulations as well as accurate correlation of relevant filtered parameters to suitable independent variables. This article deals with both of those issues. The accuracy of mTFM is touched by assessing the impact of gas sub-grid turbulence over HRS filtered predictions. A gas turbulence alike effect is artificially inserted by means of a stochastic forcing procedure implemented in the physical space over the momentum conservation equation of the gas phase. The correlation issue is touched by introducing a three-filtered variable correlation analysis (three-marker analysis) performed under a variety of different macro-scale conditions typical or risers. While the more elaborated correlation procedure clearly improved accuracy, accounting for gas sub-grid turbulence had no significant impact over predictions.

Keywords: fluidization, gas-particle flow, two-fluid model, sub-grid models, filtered closures

Procedia PDF Downloads 122
53 Optimization of the Structural Design for an Irregular Building in High Seismicity Zone

Authors: Arias Fernando, Juan Bojórquez, Edén Bojórquez, Alfredo Reyes-Salazar, Fernando de J. Velarde, Robespierre Chávez, J. Martin Leal, Victor Baca

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The present study focuses on the optimization of different structural systems employed in tall steel buildings, with a specific focus on the city of Acapulco, Guerrero, a region known for its high seismic activity. Using the spectral modal method, analyses were conducted to assess the ability of these buildings to withstand seismic forces and other external loads. After performing a detailed analysis of various models, the results were compared based on various engineering parameters, including maximum interstory drift, base shear, displacements, and the total weight of the structures, the latter being considered as an estimate of the cost of the proposed systems. The findings of this study indicate that steel frames stand out as a viable option for tall buildings in question. However, areas of potential improvement were identified, suggesting opportunities for further optimization of the design and seismic resistance of these structures. This study provides a deep and insightful perspective on the optimization of structural systems in tall steel buildings, offering valuable information for engineers and professionals in the field involved in similar projects.

Keywords: high seismic zone, irregular buildings, optimization design, steel buildings

Procedia PDF Downloads 24
52 The Long – Term Effects of a Prevention Program on the Number of Critical Incidents and Sick Leave Days: A Decade Perspective

Authors: Valerie Isaak

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Background: This study explores the effectiveness of refresher training sessions of an intervention program at reducing the employees’ risk of injury due to patient violence in a forensic psychiatric hospital. Methods: The original safety intervention program that consisted of a 3 days’ workshop was conducted in the maximum-security ward of a psychiatric hospital in Israel. Ever since the original intervention, annual refreshers were conducted, highlighting one of the safety elements covered in the original intervention. The study examines the effect of the intervention program along with the refreshers over a period of 10 years in four wards. Results: Analysis of the data demonstrates that beyond the initial reduction following the original intervention, refreshers seem to have an additional positive long-term effect, reducing both the number of violent incidents and the number of actual employee injuries in a forensic psychiatric hospital. Conclusions: We conclude that such an intervention program followed by refresher training would promote employees’ wellbeing. A healthy work environment is part of management’s commitment to improving employee wellbeing at the workplace.

Keywords: wellbeing, violence at work, intervention program refreshers, public sector mental healthcare

Procedia PDF Downloads 137
51 DNA-Based Analysis of Gut Content of Zygoribatula sp (Acari: Oribatida) and Scheloribates sp (Acari: Oribatida), under the Canopy of Prosopis Laevigata, in a Semiarid Land

Authors: Daniel Isaac Sanchez Chavez, Salvador Rodríguez Zaragoza, Patricia Velez Aguilar

Abstract:

In arid and semi-arid regions, plants are essential in the functional activity and productivity, modifying the microclimatic conditions of their environment, which allows many organisms to grow under them. Within these organisms, oribatid mites play a key role in reintegrating nutrients into the soil through the consumption of soil fungi. However, oribatid mites feed on a vast array of fungal species, which is likely to have strong impacts on their population dynamics and their environment. So, in this study, the aim was to determine the gut content of the abundant oribatid mites Zygoribatula sp and Scheloribates sp, under the canopy of the bush P. laevigata in a semi-arid zone through DNA-based analysis. The results showed the presence in the gut of both mites of different fungal taxa. Fungi, such as Aspergillus sp and Mortierella sp, probably served as a food despite the production of deterrent compounds or structures from both fungal species. Saccharomyces sp might serve as well as a food source; however, it might be part of their microbial endosymbionts. On the other hand, the presence of Beauveria sp indicates a probable pathogenicity interaction, instead of fungal consumption, since this fungus is known to be entomopathogenic. Finally, the results might indicate a feeding preference to certain soil fungi according to diverse features from both taxa.

Keywords: microenvironment, endosymbionts, Oribatida, fungi

Procedia PDF Downloads 141
50 A Dialectical Behavioral Therapy Adaptation in Reducing Depression, Anxiety, and Self-Harm in Older Adults

Authors: Valerie Alexander, Amanda Gutierrez, Veronica Campbell, Dara Schwartz, B. Charles Tatum

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It has long been assumed that personality disorders (PD) originate in adolescence or early adulthood and that the maladaptive behaviors significantly attenuate over time. The Diagnostic and Statistical Manual of Mental Disorders-5 supports early onset of PD and views the pattern of behaviors as enduring and stable. The premise of this study is that PD may not always begin early in life, that behaviors may change over the lifespan, and that current treatment modalities may be beneficial in seniors. Self-injurious behaviors (SIB) exhibited earlier in life may, in older adults, be manifested in less overt high-risk behaviors but by refusal to take medication and get necessary medical treatment. Dialectical Behavioral Therapy is a well-known treatment modality for teaching emotional regulation and distress tolerance and thus reducing self-injurious behaviors yet very little has been studied about SIB and treatment in older adults. The population for this study was older adults, with a history of SIB, a PD, and depression and/or anxiety. Participants learned an adapted version of Dialectical Behavioral Therapy (DBT) as developed by DBT trained therapists. The results provided clinical potentials for the efficacy of DBT to reduce SIB, decrease depression and anxiety in the older adult population.

Keywords: anxiety, depression, dialectical behavioral therapy, personality disorders, self-harm behavior, treatment in older adults

Procedia PDF Downloads 301
49 Ignition Interlock Device for Motorcycles

Authors: Luisito L. Lacatan, Zacha Valerie G. Ancheta, Michelangelo A. Dorado, Lester Joseph M. Ochoa, Anthony Mark G. Tayabas

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Ignition Interlock Device or IID is a mechanism installed inside a vehicle which requires the driver to breathe into the device before starting the vehicle. If the IID detects that the alcohol level or blood alcohol content (BAC) is higher than the accepted value, the engine will not start. If the driver is not able to provide a clean breath sample, the IID will log the event, warn the driver, and then start up an alarm. The purpose of the IID is to prevent accidents due to driving under the influence (DUI). With the rise of the two-wheeled vehicle in the Philippines due to its mobility and purchasing power, IIDs are still mainly installed on four-wheeled vehicles. Even though riding the motorcycle when drunk is more dangerous, there are only a small number of installed devices on motorcycles and scooters. The general objective of this study was to develop a system with hardware and software components that would implement IID on motorcycles. The study employed a descriptive method of research. The study also concluded the following: the infrared must have a point-to-point communication, the breathalyzer on the helmet should react to ethanol, the microcontroller on the motorcycle should accept all IR signals from the helmet and interpret it and the GPS shield should have an unobstructed line-of-sight communication with the GPS satellites.

Keywords: blood alcohol content, breathalyser, driving under the influence, global positioning system, global system for mobile communication

Procedia PDF Downloads 325
48 Time Delayed Susceptible-Vaccinated-Infected-Recovered-Susceptible Epidemic Model along with Nonlinear Incidence and Nonlinear Treatment

Authors: Kanica Goel, Nilam

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Infectious diseases are a leading cause of death worldwide and hence a great challenge for every nation. Thus, it becomes utmost essential to prevent and reduce the spread of infectious disease among humans. Mathematical models help to better understand the transmission dynamics and spread of infections. For this purpose, in the present article, we have proposed a nonlinear time-delayed SVIRS (Susceptible-Vaccinated-Infected-Recovered-Susceptible) mathematical model with nonlinear type incidence rate and nonlinear type treatment rate. Analytical study of the model shows that model exhibits two types of equilibrium points, namely, disease-free equilibrium and endemic equilibrium. Further, for the long-term behavior of the model, stability of the model is discussed with the help of basic reproduction number R₀ and we showed that disease-free equilibrium is locally asymptotically stable if the basic reproduction number R₀ is less than one and unstable if the basic reproduction number R₀ is greater than one for the time lag τ≥0. Furthermore, when basic reproduction number R₀ is one, using center manifold theory and Casillo-Chavez and Song theorem, we showed that the model undergoes transcritical bifurcation. Moreover, numerical simulations are being carried out using MATLAB 2012b to illustrate the theoretical results.

Keywords: nonlinear incidence rate, nonlinear treatment rate, stability, time delayed SVIRS epidemic model

Procedia PDF Downloads 148
47 The Pedagogical Force of Land and Art in Graduate Social Work A/R/Tographic Research

Authors: Valerie Triggs, Michele Sorensen

Abstract:

As two university professors in postsecondary faculties of social work and education, we have observed that students often recognize the importance of learning facts about colonization but have difficulty grappling with how they themselves might be implicated in reconciliation or how they might respond to these facts in meaningful ways. The detachment observed between students and factual information results in the initiation of a research study centered around an approach to teaching the course. This involved transitioning its pedagogical format to embrace a/r/tographic methods of teaching, learning, and inquiry. By taking seriously the arguments of various Indigenous scholars for learning from the land and by working alongside traditional Indigenous knowledge, we chose to engage a speculative approach to course design and teaching, which actually used the land as one of the course texts. We incorporated art practices that involved connecting bodies with land as well as using land materials in various creative and aesthetic projects while being informed by Medicine Keepers, Indigenous and settler artists, and knowledge-keeper helpers. In this study, we share some of the unanticipated themes that arose when students began to allow land and artmaking, both aesthetically and intuitively, through both joy and sorrow, to affect a reimagining and repositioning of selves and relations. We found that time and engagement with land and art began to build more empathic understanding and foster personal and professional practices grounded in respect, relevance, reciprocity, and responsibility.

Keywords: reconciliation, decolonization, artmaking, respect

Procedia PDF Downloads 46
46 High Resolution Solid State NMR Structural Study of a Ternary Hydraulic Mixture

Authors: Rym Sassi, Franck Fayon, Mohend Chaouche, Emmanuel Veron, Valerie Montouillout

Abstract:

The chemical phenomena occurring during cement hydration are complex and interdependent, and even after almost two centuries of studies, they are still difficult to solve for complex mixtures combining different hydraulic binders. Powder-XRD has been widely used for characterizing the crystalline phases in both anhydrous and hydrated cement, but only limited information is obtained in the case of strongly disordered and amorphous phases. In contrast, local spectroscopies like solid-state NMR can provide a quantitative description of noncrystalline phases. In this work, the structural modifications occurring during hydration of a fast-setting ternary binder based on white Portland cement, white calcium aluminate cement, and calcium sulfate were investigated using advanced solid-state NMR methods. We particularly focused on the early stage of the hydration up to 28 days, working with samples whose hydration was controlled and stopped. ²⁷Al MQ-MAS as well as {¹H}-²⁷Al and {¹H}-²⁹Si Cross- Polarization MAS NMR techniques were combined to distinguish all of the aluminum and silicon species formed during the hydration. The NMR quantification of the different phases was conducted in parallel with the XRD analyses. The consumption of initial products, as well as the precipitation of hydraulic phases (ettringite, monosulfate, strätlingite, CSH, and CASH), were unambiguously quantified. Finally, the drawing of the consumption and formation of phases was correlated with mechanical strength measurements.

Keywords: cement, hydration, hydrates structure, mechanical strength, NMR

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45 Evaluation of the Pain of Patients with Chronic Renal Disease in Hemodialysis

Authors: Fabiana Souza Orlandi, Izabel Cristina Chavez Gomes, Barbara Isabela De Paula Morais, Ana Carolina Ottaviani

Abstract:

Chronic Kidney Disease (CKD) is considered a public health problem. Patients who present CKD in their more advanced stages usually present several biopsychosocial changes, which may include pain. Pain can be considered subjective and personal, and its perception is characterized as a multidimensional experience. The objective of this study was to evaluate the level and descriptors of pain of adults and elderly patients with chronic kidney disease, through the Multidimensional Pain Evaluation Scale (EMADOR). This is a descriptive cross-sectional study with a quantitative approach. The sample consisted of 100 subjects with CKD in hemodialysis treatment at a Renal Replacement Therapy Service in the interior of the state of São Paulo. Data were collected through an individual interview, using a Sociodemographic Characterization and Multidimensional Pain Evaluation Scale (EMADOR). All ethical precepts were respected. The majority of the respondents were men (61.0%), white (56.0%) and with a high school education (34.0%). Regarding the pain of the individuals, 89 patients reported pain, with Chronic Pain predominating (50.0%, n = 50), followed by Acute Pain (39.0%, n = 39). Of the subjects who presented acute pain most of the 89.0% described the pain felt as unbearable, and of those who presented chronic pain, 35.0% described the pain felt as painful, unbearable and uncomfortable. It was concluded that there was a significant presence of pain, being the chronic pain dominant in the studied population. Faced with such factors, the present study motivates researches in this population, in order to establish interventions with the objective of improving the quality of life of these individuals.

Keywords: pain, chronic kidney disease, dialysis, evaluation

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44 Microstructural Characterization of Creep Damage Evolution in Welded Inconel 600 Superalloy

Authors: Lourdes Yareth Herrera-Chavez, Alberto Ruiz, Victor H. Lopez

Abstract:

Superalloys are used in components that operate at high temperatures such as pressure vessels and heat exchanger tubing. Design standards for these components must consider creep resistance among other criteria. Fusion welding processes are commonly used in the industry to join such components. Fusion processes commonly generate three distinctive zones, i.e. heat affected zone (HAZ), namely weld metal (WM) and base metal (BM). In nickel-based superalloy, the microstructure developed during fusion welding dictates the mechanical response of the welded component and it is very important to establish these effects in the mechanical response of the component. In this work, two plates of Inconel 600 superalloy were Gas Metal Arc Welded (GMAW). Creep samples were cut and milled to specifications and creep tested at a temperature (650 °C) using stress level of 350, 300, 275, 250 and 200 MPa. Microstructural analysis results showed a progressive creep damage evolution that depends on the stress levels with a preferential accumulation of creep damage at the heat affected zone where the creep rupture preferentially occurs owing to an austenitic matrix with grain boundary precipitated of the type Cr23C6. The fractured surfaces showed dimple patterns of cavity and voids. Results indicated that the damage mechanism is due to cavity growth by the combined effect of the power law and diffusion creep.

Keywords: austenitic microstructure, creep damage evolution, heat affected zone, vickers microhardness

Procedia PDF Downloads 202