Search results for: air temperature difference
Commenced in January 2007
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Edition: International
Paper Count: 11062

Search results for: air temperature difference

6532 Impact of pH Control on Peptide Profile and Antigenicity of Whey Hydrolysates

Authors: Natalia Caldeira De Carvalho, Tassia Batista Pessato, Luis Gustavo R. Fernandes, Ricardo L. Zollner, Flavia Maria Netto

Abstract:

Protein hydrolysates are ingredients of enteral diets and hypoallergenic formulas. Enzymatic hydrolysis is the most commonly used method for reducing the antigenicity of milk protein. The antigenicity and physicochemical characteristics of the protein hydrolysates depend on the reaction parameters. Among them, pH has been pointed out as of the major importance. Hydrolysis reaction in laboratory scale is commonly carried out under controlled pH (pH-stat). However, from the industrial point of view, controlling pH during hydrolysis reaction may be infeasible. This study evaluated the impact of pH control on the physicochemical properties and antigenicity of the hydrolysates of whey proteins with Alcalase. Whey protein isolate (WPI) solutions containing 3 and 7 % protein (w/v) were hydrolyzed with Alcalase 50 and 100 U g-1 protein at 60°C for 180 min. The reactions were carried out under controlled and uncontrolled pH conditions. Hydrolyses performed under controlled pH (pH-stat) were initially adjusted and maintained at pH 8.5. Hydrolyses carried out without pH control were initially adjusted to pH 8.5. Degree of hydrolysis (DH) was determined by OPA method, peptides profile was evaluated by HPLC-RP, and molecular mass distribution by SDS-PAGE/Tricine. The residual α-lactalbumin (α-La) and β-lactoglobulin (β-Lg) concentrations were determined using commercial ELISA kits. The specific IgE and IgG binding capacity of hydrolysates was evaluated by ELISA technique, using polyclonal antibodies obtained by immunization of female BALB/c mice with α-La, β-Lg and BSA. In hydrolysis under uncontrolled pH, the pH dropped from 8.5 to 7.0 during the first 15 min, remaining constant throughout the process. No significant difference was observed between the DH of the hydrolysates obtained under controlled and uncontrolled pH conditions. Although all hydrolysates showed hydrophilic character and low molecular mass peptides, hydrolysates obtained with and without pH control exhibited different chromatographic profiles. Hydrolysis under uncontrolled pH released, predominantly, peptides between 3.5 and 6.5 kDa, while hydrolysis under controlled pH released peptides smaller than 3.5 kDa. Hydrolysis with Alcalase under all conditions studied decreased by 99.9% the α-La and β-Lg concentrations in the hydrolysates detected by commercial kits. In general, β-Lg concentrations detected in the hydrolysates obtained under uncontrolled pH were significantly higher (p<0.05) than those detected in hydrolysates produced with pH control. The anti-α-La and anti-β-Lg IgE and IgG responses to all hydrolysates decreased significantly compared to WPI. Levels of specific IgE and IgG to the hydrolysates were below 25 and 12 ng ml-1, respectively. Despite the differences in peptide composition and α-La and β-Lg concentrations, no significant difference was found between IgE and IgG binding capacity of hydrolysates obtained with or without pH control. These results highlight the impact of pH on the hydrolysates characteristics and their concentrations of antigenic protein. Divergence between the antigen detection by commercial ELISA kits and specific IgE and IgG binding response was found in this study. This result shows that lower protein detection does not imply in lower protein antigenicity. Thus, the use of commercial kits for allergen contamination analysis should be cautious.

Keywords: allergy, enzymatic hydrolysis, milk protein, pH conditions, physicochemical characteristics

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6531 Synthesis, Characterization and Photocatalytic Applications of Ag-Doped-SnO₂ Nanoparticles by Sol-Gel Method

Authors: M. S. Abd El-Sadek, M. A. Omar, Gharib M. Taha

Abstract:

In recent years, photocatalytic degradation of various kinds of organic and inorganic pollutants using semiconductor powders as photocatalysts has been extensively studied. Owing to its relatively high photocatalytic activity, biological and chemical stability, low cost, nonpoisonous and long stable life, Tin oxide materials have been widely used as catalysts in chemical reactions, including synthesis of vinyl ketone, oxidation of methanol and so on. Tin oxide (SnO₂), with a rutile-type crystalline structure, is an n-type wide band gap (3.6 eV) semiconductor that presents a proper combination of chemical, electronic and optical properties that make it advantageous in several applications. In the present work, SnO₂ nanoparticles were synthesized at room temperature by the sol-gel process and thermohydrolysis of SnCl₂ in isopropanol by controlling the crystallite size through calculations. The synthesized nanoparticles were identified by using XRD analysis, TEM, FT-IR, and Uv-Visible spectroscopic techniques. The crystalline structure and grain size of the synthesized samples were analyzed by X-Ray diffraction analysis (XRD) and the XRD patterns confirmed the presence of tetragonal phase SnO₂. In this study, Methylene blue degradation was tested by using SnO₂ nanoparticles (at different calculations temperatures) as a photocatalyst under sunlight as a source of irradiation. The results showed that the highest percentage of degradation of Methylene blue dye was obtained by using SnO₂ photocatalyst at calculations temperature 800 ᵒC. The operational parameters were investigated to be optimized to the best conditions which result in complete removal of organic pollutants from aqueous solution. It was found that the degradation of dyes depends on several parameters such as irradiation time, initial dye concentration, the dose of the catalyst and the presence of metals such as silver as a dopant and its concentration. Percent degradation was increased with irradiation time. The degradation efficiency decreased as the initial concentration of the dye increased. The degradation efficiency increased as the dose of the catalyst increased to a certain level and by further increasing the SnO₂ photocatalyst dose, the degradation efficiency is decreased. The best degradation efficiency on which obtained from pure SnO₂ compared with SnO₂ which doped by different percentage of Ag.

Keywords: SnO₂ nanoparticles, a sol-gel method, photocatalytic applications, methylene blue, degradation efficiency

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6530 Impact of the 2015 Drought on Rural Livelihood – a Case Study of Masurdi Village in Latur District of Maharashtra, India

Authors: Nitin Bhagat

Abstract:

Drought is a global phenomenon. It has a huge impact on agriculture and allied sector activities. Agriculture plays a substantial role in the economy of developing countries, which mainly depends on rainfall. The present study illustrates the drought conditions in Masurdi village of Latur district in the Marathwada region, Maharashtra. This paper is based on both primary as well as secondary data sources. The multistage sample method was used for primary data collection. The 100 households sample survey data has been collected from the village through a semi-structured questionnaire. The crop production data is collected from the Department of Agriculture, Government of Maharashtra. The rainfall data is obtained from the Department of Revenue, Office of Divisional Commissioner, Aurangabad for the period from 1988 to 2018. This paper examines the severity of drought consequences of the 2015 drought on domestic water supply, crop production, and the effect on children's schooling, livestock assets, bank credit, and migration. The study also analyzed climate variables' impact on the Latur district's total food grain production for 19 years from 2000 to 2018. This study applied multiple regression analysis to check the relationship between climatic variables and the Latur district's total food grain production. The climate variables are annual rainfall, maximum temperature and minimum temperature. The study considered that climatic variables are independent variables and total food grain as the dependent variable. It shows there is a significant relationship between rainfall and maximum temperature. The study also calculated rainfall deviations to find out the drought and normal years. According to drought manual 2016, the rainfall deviation calculated using the following formula. RF dev = {(RFi – RFn) / RFn}*100.Approximately 27.43 % of the workforce migrated from rural to urban areas for searching jobs, and crop production decreased tremendously due to inadequate rainfall in the drought year 2015. Many farm and non-farm labor, some marginal and small cultivators, migrated from rural to urban areas (like Pune, Mumbai, and Western Maharashtra).About 48 % of the households' children faced education difficulties; in the drought period, children were not going to school. They left their school and joined to bring water with their mother and fathers, sometimes they fetched water on their head or using a bicycle, near about 2 km from the village. In their school-going days, drinking water was not available in their schools, so the government declared holidays early in the academic education year 2015-16 compared to another academic year. Some college and 10th class students left their education due to financial problems. Many households benefited from state government schemes, like drought subsidies, crop insurance, and bank loans. Out of 100 households, about 50 (50 %) have obtained financial support from the state government’s subsidy scheme, 58 ( 58 %) have got crop insurance, and 41(41 %) irrigated households have got bank loans from national banks; besides that, only two families have obtained loans from their relatives and moneylenders.

Keywords: agriculture, drought, household, rainfall

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6529 Role of Judiciary in Developing Countries

Authors: Amir Shafiq, Asif Shahzad, Shabbar Mehmood, Muhammad Saeed, Hamid Mustafa

Abstract:

Administration of justice in a society is evolutionary process. In pre-modern societies vital organs that we consider separate today i.e. legislation, implementation and adjudication were controlled by a King, the sovereign authority. Whereas now it is recognized that Development of a country revolves in seven arenas i.e. Civil Society, Political Society, Economic Society, Legislature, Judiciary, Executive & Bureaucracy. Each society whether developing or developed, has need of institutions and structures that can resolve difference of opinions of private or public nature between contending parties. Administration of justice has a key-role in the development of the society. Through this paper, it is to highlight that an independent judiciary having the support of public opinion therefore is inevitable to wriggle out from such problems in order to restore and protect the fundamental rights, constitution and democratic political system in third world countries like Pakistan.

Keywords: role of judiciary, developing countries, judicial activism, present scenario

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6528 The Study of Hydro Physical Complex Characteristic of Clay Soil-Ground of Colchis Lowland

Authors: Paata Sitchinava

Abstract:

It has been studied phenomena subjected on the water physical (hydrophysical, mineralogy containing, specific hydrophysical) class of heavy clay soils of the Colchis lowland, according to various categories and forms of the porous water, which will be the base of the distributed used methods of the engineering practice and reclamation effectiveness evaluation. According to of clay grounds data, it has been chosen three research bases section in the central part of lowland, where has implemented investigation works by using a special program. It has been established, that three of cuts are somewhat identical, and by morphological grounds separated layers are the difference by Gallic quality. It has been implemented suitable laboratory experimental research at the samples taken from the cuts, at the base of these created classification mark of physical-technical characteristic, which is the base of suitable calculation of hydrophysical researches.

Keywords: Colchis lowland, drainage, water, soil-ground

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6527 Characterization of Pigments in an Egyptian Icon

Authors: Mohamed Abd Elfattah Ibraheem Elghrbawy

Abstract:

Icons are a significant group of cultural heritage objects that deserve to be maintained and conserved, as these ions are performed according to religious standards and norms. The ideal structure of icons is five strata, the lower layer is a wood plate, and the upper layer is the varnish layer that is exposed to photo-oxidation, that is turned into a fragile yellow layer. In addition, the components of the icons are important in dating these ions, so X-Ray Fluorescence (XRF), X-Ray Diffraction (XRD), and Scanning Electron Microscopy with energy dispersive X-ray spectroscopy (SEM-EDX) patterns were used. SEM-EDX pattern revealed that the red pigment was vermillion (HgS), that was used in the late period, with a slight difference from the synthesized pigment. Pigments were subjected to chromatic alteration due to different agents, such as microbial agents and pollutants, in particular SO₂, whereas the pigment-based pigments are more sensitive. Moreover, cleaning, varnish removal, and retouching are important processes in the conservation of icons.

Keywords: conservation, cultural heritage, Egyptian icon, pigments

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6526 Greening of Supply Chains: Benefits and Challenges Faced

Authors: Anurag Reddy Ramireddy, Abrar Ahmed, G. Sourya Sri Harsha, Pushkala Muralidharan

Abstract:

Supply chains have been developing over time since the inception of commercial trade and barter. The Green Supply Chain Management (GSCM) is a powerful way to differentiate a company from its competitors and it can greatly influence the plan success. With increased awareness to corporate responsibility and the requirement to meet the terms with environmental policy, GSCM is becoming increasingly important for companies. This paper explains the concept of green supply chain management, the difference between conventional supply chain management and green supply management and how GSCM benefits organizations while at the same time supporting a sustainable environment system. An effort has also been made to analyse research already done in this field while exploring the challenges and barriers that organizations face in implementing GSCM practices in their existing systems.

Keywords: corporate social responsibility, green supply chain management, sustainability

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6525 Brand Placement Practices in the Movies and Their Importance on Brand Recall

Authors: Elif Esiyok

Abstract:

Brand placement practices have become a popular advertising strategy, which is widely used in movies. Whether these brands are remembered by the audience after the film, or if they affect the purchasing preferences of the consumers has become one of the most important topics in the field of advertising. From this point, in this study, the "Devil Wears Prada" movie which includes high amount of brand placements is chosen. The movie watched to the undergraduate students in Turkey to measure the impact of brand placements on the attitudes of the consumers relating with a specific brand. In total 100 students were the subjects of this study. The participants were selected through using a simple random sampling method. The findings revealed that there is a significant difference between male and females in terms of brand recall. Female students were remembered the fashion brands more than the males, whereas males generally recalled the automotive brands and restaurant names.

Keywords: brand placement, brand recall, advertising, media

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6524 Cold Metal Transfer Welding of Dissimilar Thickness 6061-T6 to 5182-O Aluminum Alloys

Authors: A. Elrefaei

Abstract:

The possibility of having sheets with different thicknesses and materials in one assembly facilitates the optimal material distribution within the final product and reduces the weight of the structure. Ability of joining process to assembly these different material combinations is always a challenge to the designer. In this study, 0.6 mm thick 6061-T6 and 2 mm thick 5182-O were robot CMT welded using ER5356 and ER4043 filler metals. The thermal effect of welding resulted in a loss of hardness in the 6061 HAZ. Joints welded by ER5356 filler metal were much higher in fracture load than joints welded by ER4043 and the elongation of joints welded by ER5356 was almost double its corresponding joints welded by ER4043 filler. Owing to the big difference in formability and thickness of base metals, the fracture in forming test occurred in the softened 6061 HAZ out from the weld centerline.

Keywords: aluminum, CMT, mechanical, welding

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6523 Feasibility Study and Energy Conversion Evaluation of Agricultural Waste Gasification in the Pomelo Garden, Taiwan

Authors: Yi-Hao Pai, Wen-Feng Chen

Abstract:

The planting area of Pomelo in Hualien, Taiwan amounts to thousands of hectares. Especially in the blooming season of Pomelo, it is an important producing area for Pomelo honey, and it is also a good test field for promoting the "Under-forest Economy". However, in the current Pomelo garden planting and management operations, the large amount of agricultural waste generated by the pruning of the branches causes environmental sanitation concerns, which can lead to the hiding of pests or the infection of the Pomelo tree, and indirectly increase the health risks of bees. Therefore, how to deal with the pruning of the branches and avoid open burning is a topic of social concern in recent years. In this research, afeasibility study evaluating energy conversion efficiency through agricultural waste gasification from the Pomelo garden, Taiwan, is demonstrated. we used a high-temperature gasifier to convert the pruning of the branches into syngas and biochar. In terms of syngas composition and calorific value assessment, we use the biogas monitoring system for analysis. Then, we used Raman spectroscopy and electron microscopy (EM) to diagnose the microstructure and surface morphology of biochar. The results indicate that the 1 ton of pruning of the branches can produce 1797.03m3 of syngas, corresponding to a calorific value of 9.1MJ/m3. The main components of the gas include CH4, H2, CO, and CO2, and the corresponding gas composition ratio is 16.8%, 7.1%, 13.7%, and 24.5%. Through the biomass syngas generator with a conversion efficiency of 30% for power generation, a total of 1,358kWh can be obtained per ton of pruning of the branches. In the research of biochar, its main characteristics in Raman spectroscopy are G bands and D bands. The first-order G and D bands are at 1580 and 1350 cm⁻¹, respectively. The G bands originates from the in-plane tangential stretching of the C−C bonds in the graphitic structure, and theD band corresponds to scattering from local defects or disorders present in carbon. The area ratio of D and G peaks (D/G) increases with the decrease of reaction temperature. The larger the D/G, the higher the defect concentration and the higher the porosity. This result is consistent with the microstructure displayed by SEM. The study is expected to be able to reuse agricultural waste and promote the development of agricultural and green energy circular economy.

Keywords: agricultural waste, gasification, energy conversion, pomelo garden

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6522 The Role of Digital Media in the Change of Saudi Nationalism: A Systematic Review and Meta-Analysis

Authors: Alaa Alshaikh

Abstract:

While digital technologies were initially seen as harbingers of globalisation and cosmopolitanism, scholars increasingly acknowledge their role in the rise of nationalism. This paper studies the national identity in light of the digital media in Saudi Arabia. It offers an extensive meta-analysis of the evolution of the national identity on social media. It examines the national identity and its components and deals with the difference between it and digital nationalism, which is formed and affected by the country's fulfillment of the citizen's needs. Hereto a systematic examination of all 40 articles published between October 2016 and December 2022 was conducted. Findings indicate that three characteristics of contemporary nationalism are partly linked to recent shifts in digital communication: diversification, fragmentation, and commodification. The paper concludes by considering the implications of our arguments for future research in the field.

Keywords: meta analysis, Saudi Arabia, nationalism, social media

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6521 Students' Perception of Using Dental E-Models in an Inquiry-Based Curriculum

Authors: Yanqi Yang, Chongshan Liao, Cheuk Hin Ho, Susan Bridges

Abstract:

Aim: To investigate student’s perceptions of using e-models in an inquiry-based curriculum. Approach: 52 second-year dental students completed a pre- and post-test questionnaire relating to their perceptions of e-models and their use in inquiry-based learning. The pre-test occurred prior to any learning with e-models. The follow-up survey was conducted after one year's experience of using e-models. Results: There was no significant difference between the two sets of questionnaires regarding student’s perceptions of the usefulness of e-models and their willingness to use e-models in future inquiry-based learning. Most of the students preferred using both plaster models and e-models in tandem. Conclusion: Students did not change their attitude towards e-models and most of them agreed or were neutral that e-models are useful in inquiry-based learning. Whilst recognizing the utility of 3D models for learning, student's preference for combining these with solid models has implications for the development of haptic sensibility in an operative discipline.

Keywords: e-models, inquiry-based curriculum, education, questionnaire

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6520 Enterprise Harmonic Fusion as National Sustainability

Authors: L. R. Valencia Pérez, J. M. Peña Aguilar, Valencia Pérez, Héctor Fernando, Lamadrid A. Alberto, Vivanco V. Martín

Abstract:

Cosmology is a discipline commonly linked to philosophy. In this work, we show cosmology, from a perspective that can provide some proposals to help develop SMB in Mexico. We start from the belief that, in a complex world, the solutions to problems must nurture from different approaches. In order to be able to do this, we need to change our point of reference and use theoretical proposals and methodologies that came from other disciplines; in this case, we will try to show that between philosophy and administration exist dialogs that need to be incentivized. The work is structured in three parts. In the first one, we create a description of cosmology and how it could be applied to business. In the second, we show some of the most common problems that the SMB suffer from and in the third, we present a proposal of how cosmology can help improve the development. Finally, we concluded that better understanding of real needs, integration of knowledge at large scale and using information technologies within the cosmology framework presentment could make a difference.

Keywords: harmonic fusion, national sustainability, financial management, triple helix

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6519 Introduction of PMMA-Tag to VHH for Improving Recovery and Immobilization Rate of VHHS

Authors: Bongmun Kang, Kagnari Yamakawa, Yoshihisa Hagihara, Yuji Ito, Michimasa Kishimoto, Yoichi Kumada

Abstract:

The PMMA-tag was genetically fused with the C-terminal region of VHH molecules. This antibody, VHH, is known as a single-chain domain, which is devoid of light chains. The PMMA-tag, which could affect the isoelectric point (pI) changeable with a charge of amino acid in VHHs were closely related to the solubility of VHH molecules during refolding. The genetic fusion of PMMA-tag to C-terminal region of VHHs significantly affects the recovery of their soluble protein during refolding by 50 mM TAPS at pH 8.5. It could be refolded with a recovery of more than 95% by dialysis at pH 8.5. A marked difference in the antigen-binding activities in the adsorption state was significantly high in VHH-PM compared to the wild type of VHH. There are approximately 8-fold differences in the antigen-binding activities in the adsorption state between VHH-PM and VHH.

Keywords: VHH, PMMA-tag, isoelectric point, pH, Solubility, refolding, immobilization, ELISA

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6518 Willingness and Attitude towards Organ Donation of Nurses in Taiwan

Authors: ShuYing Chung, Minchuan Huang, Iping Chen

Abstract:

Taking the medical staff in an emergency ward of a medical center in Central Taiwan as the research object, the questionnaire data were collected by anonymous and voluntary reporting methods with structured questionnaire to explore the actual situation, willingness and attitude of organ donation. Only 80 valid questionnaires were collected. Among the 8 questions, the average correct rate was 5.9 + 1.2, and the correct rate was 73.13%. The willingness of organ donation that 7.5% of the people are not willing; 92.5% of the people are willing, of which 62.5% have considered but have not yet decided; 21.3% are willing but have not signed the consent of organ donation; They have signed the consent of organ donation 8.7%. The average total score (standard deviation) of attitude towards organ donation was 36.2. There is no significant difference between the demographic variables and the awareness and willingness of organ donation, but there is a significant correlation between the marital status and the attitude of organ donation.

Keywords: clinical psychology, organ donation, doctors affecting psychological disorders, commitment

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6517 Formulation of a Submicron Delivery System including a Platelet Lysate to Be Administered in Damaged Skin

Authors: Sergio A. Bernal-Chavez, Sergio Alcalá-Alcalá, Doris A. Cerecedo-Mercado, Adriana Ganem-Rondero

Abstract:

The prevalence of people with chronic wounds has increased dramatically by many factors including smoking, obesity and chronic diseases, such as diabetes, that can slow the healing process and increase the risk of becoming chronic. Because of this situation, the improvement of chronic wound treatments is a necessity, which has led to the scientific community to focus on improving the effectiveness of current therapies and the development of new treatments. The wound formation is a physiological complex process, which is characterized by an inflammatory stage with the presence of proinflammatory cells that create a proteolytic microenvironment during the healing process, which includes the degradation of important growth factors and cytokines. This decrease of growth factors and cytokines provides an interesting strategy for wound healing if they are administered externally. The use of nanometric drug delivery systems, such as polymer nanoparticles (NP), also offers an interesting alternative around dermal systems. An interesting strategy would be to propose a formulation based on a thermosensitive hydrogel loaded with polymeric nanoparticles that allows the inclusion and application of a platelet lysate (PL) on damaged skin, with the aim of promoting wound healing. In this work, NP were prepared by a double emulsion-solvent evaporation technique, using polylactic-co-glycolic acid (PLGA) as biodegradable polymer. Firstly, an aqueous solution of PL was emulsified into a PLGA organic solution, previously prepared in dichloromethane (DCM). Then, this disperse system (W/O) was poured into a polyvinyl alcohol (PVA) solution to get the double emulsion (W/O/W), finally the DCM was evaporated by magnetic stirring resulting in the NP formation containing PL. Once the NP were obtained, these systems were characterized by morphology, particle size, Z-potential, encapsulation efficiency (%EE), physical stability, infrared spectrum, calorimetric studies (DSC) and in vitro release profile. The optimized nanoparticles were included in a thermosensitive gel formulation of Pluronic® F-127. The gel was prepared by the cold method at 4 °C and 20% of polymer concentration. Viscosity, sol-gel phase transition, time of no flow solid-gel at wound temperature, changes in particle size by temperature-effect using dynamic light scattering (DLS), occlusive effect, gel degradation, infrared spectrum and micellar point by DSC were evaluated in all gel formulations. PLGA NP of 267 ± 10.5 nm and Z-potential of -29.1 ± 1 mV were obtained. TEM micrographs verified the size of NP and evidenced their spherical shape. The %EE for the system was around 99%. Thermograms and in infrared spectra mark the presence of PL in NP. The systems did not show significant changes in the parameters mentioned above, during the stability studies. Regarding the gel formulation, the transition sol-gel occurred at 28 °C with a time of no flow solid-gel of 7 min at 33°C (common wound temperature). Calorimetric, DLS and infrared studies corroborated the physical properties of a thermosensitive gel, such as the micellar point. In conclusion, the thermosensitive gel described in this work, contains therapeutic amounts of PL and fulfills the technological properties to be used in damaged skin, with potential application in wound healing and tissue regeneration.

Keywords: growth factors, polymeric nanoparticles, thermosensitive hydrogels, tissue regeneration

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6516 Metallic-Diamond Tools with Increased Abrasive Wear Resistance for Grinding Industrial Floor Systems

Authors: Elżbieta Cygan, Bączek, Piotr Wyżga

Abstract:

This paper presents the results of research on the physical, mechanical, and tribological properties of materials constituting the matrix in sintered metallic-diamond tools. The ground powders based on the Fe-Mn-Cu-Sn-C system were modified with micro-sized particles of the ceramic phase: SiC, Al₂O₃ and consolidated using the SPS (spark plasma sintering) method to a relative density of over 98% at 850-950°C, at a pressure of 35 MPa and time 10 min. After sintering, an analysis of the microstructure was conducted using scanning electron microscopy. The resulting materials were tested for the apparent density determined by Archimedes’ method, Rockwell hardness (scale B), Young’s modulus, as well as for technological properties. The performance results of obtained diamond composites were compared with the base material (Fe–Mn–Cu–Sn–C) and the commercial alloy Co-20% WC. The hardness of composites has achieved the maximum at a temperature of 900°C; therefore, it should be considered that at this temperature it was obtained optimal physical and mechanical properties of the subjects' composites were. Research on tribological properties showed that the composites modified with micro-sized particles of the ceramic phase are characterized by more than twice higher wear resistance in comparison with base materials and the commercial alloy Co-20% WC. Composites containing Al₂O₃ phase particles in the matrix material were composites containing Al₂O₃ phase particles in the matrix material were characterized by the lowest abrasion wear resistance. The manufacturing technology presented in the paper is economically justified and can be successfully used in the production process of the matrix in sintered diamond-impregnated tools used for the machining of an industrial floor system. Acknowledgment: The study was performed under LIDER IX Research Project No. LIDER/22/0085/L-9/17/NCBR/2018 entitled “Innovative metal-diamond tools without the addition of critical raw materials for applications in the process of grinding industrial floor systems” funded by the National Centre for Research and Development of Poland, Warsaw.

Keywords: abrasive wear resistance, metal matrix composites, sintered diamond tools, Spark Plasma Sintering

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6515 Effect of Silver Nanoparticles in Temperature Polarization of Distillation Membranes for Desalination Technologies

Authors: Lopez J., Mehrvar M., Quinones E., Suarez A., Romero C.

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Membrane Distillation is an emerging technology that uses thermal and membrane steps for the desalination process to get drinking water. In this study, silver nanoparticles (AgNP) were deposited by dip-coating process over Polyvinylidene Fluoride, Fiberglass hydrophilic, and Polytetrafluoroethylene hydrophobic commercial membranes as substrate. Membranes were characterized and used in a Vacuum Membrane Distillation cell under Ultraviolet light with sea salt feed solution. The presence of AgNP increases the absorption of energy on the membrane, which improves the transmembrane flux.

Keywords: silver nanoparticles, membrane distillation, desalination technologies, heat deliver

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6514 Influence of Channel Depth on the Performance of Wavy Fin Absorber Solar Air Heater

Authors: Abhishek Priyam, Prabha Chand

Abstract:

Channel depth is an important design parameter to be fixed in designing a solar air heater. In this paper, a mathematical model has been developed to study the influence of channel duct on the thermal performance of solar air heaters. The channel depth has been varied from 1.5 cm to 3.5 cm for the mass flow range 0.01 to 0.11 kg/s. Based on first law of thermodynamics, the channel depth of 1.5 cm shows better thermal performance for all the mass flow range. Also, better thermohydraulic performance has been found up to 0.05 kg/s, and beyond this, thermohydraulic efficiency starts decreasing. It has been seen that, with the increase in the mass flow rate, the difference between thermal and thermohydraulic efficiency increases because of the increase in pressure drop. At lower mass flow rate, 0.01 kg/s, the thermal and thermohydraulic efficiencies for respective channel depth remain the same.

Keywords: channel depth, thermal efficiency, wavy fin, thermohydraulic efficiency

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6513 High-Temperature Corrosion of Aluminized and Chromized Fe-25.8%Cr-19.5%Ni Alloys in N2/H2S/H2O-mixed Gases

Authors: Min Jung Kim, Dong Bok Lee

Abstract:

Alloys of Fe-25.8%Cr-19.5%Ni (SUS310 stainless steel) were either chromized or aluminized via pack cementation, and corroded at 800 oC for 100 h in 1 atm of (0.9448 atm of N2+0.031 atm of H2O+0.0242 atm of H2S)-mixed gases. The chromized layer consisted primarily of Cr1.36Fe0.52 and some Cr23C6. Its corrosion resulted in the formation of Cr2S3 and some FeS and Fe5Ni4S8. The aluminized coating consisted primarily of FeAl. Its corrosion resulted in the formation of α-Al2O3, Al2S3, and Cr2S3. Aluminizing was more effective than chromizing in increasing the corrosion resistance of the substrate, due mainly to the formation of α-Al2O3.

Keywords: aluminizing, chromizing, corrosion, H2S gas

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6512 A Simple Light-Outcoupling Enhancement Method for Organic Light-Emitting Diodes

Authors: Ho-Nyeon Lee

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We propose to use a gradual-refractive-index dielectric (GRID) as a simple and efficient light-outcoupling method for organic light-emitting diodes (OLEDs). Using the simple GRIDs, we could improve the light outcoupling efficiency of OLEDs rather than relying on difficult nano-patterning processes. Through numerical simulations using a finite-difference time-domain (FDTD) method, the feasibility of the GRID structure was examined and the design parameters were extracted. The outcoupling enhancement effects due to the GRIDs were proved through severe experimental works. The GRIDs were adapted to bottom-emission OLEDs and top-emission OLEDs. For bottom-emission OLEDs, the efficiency was improved more than 20%, and for top-emission OLEDs, more than 40%. The detailed numerical and experimental results will be presented at the conference site.

Keywords: efficiency, GRID, light outcoupling, OLED

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6511 Study Habits and Level of Difficulty Encountered by Maltese Students Studying Biology Advanced Level Topics

Authors: Marthese Azzopardi, Liberato Camilleri

Abstract:

This research was performed to investigate the study habits and level of difficulty perceived by post-secondary students in Biology at Advanced-level topics after completing their first year of study. At the end of a two-year ‘sixth form’ course, Maltese students sit for the Matriculation and Secondary Education Certificate (MATSEC) Advanced-level biology exam as a requirement to pursue science-related studies at the University of Malta. The sample was composed of 23 students (16 taking Chemistry and seven taking some ‘Other’ subject at the Advanced Level). The cohort comprised seven males and 16 females. A questionnaire constructed by the authors, was answered anonymously during the last lecture at the end of the first year of study, in May 2016. The Chi square test revealed that gender plays no effect on the various study habits (c2 (6) = 5.873, p = 0.438). ‘Reading both notes and textbooks’ was the most common method adopted by males (71.4%), whereas ‘Writing notes on each topic’ was that mostly used by females (81.3%). The Mann-Whitney U test showed no significant difference in the study habits of students and the mean assessment mark obtained at the end of the first year course (p = 0.231). Statistical difference was found with the One-ANOVA test when comparing the mean assessment mark obtained at the end of the first year course when students are clustered by their Secondary Education Certificate (SEC) grade (p < 0.001). Those obtaining a SEC grade of 2 and 3 got the highest mean assessment of 68.33% and 66.9%, respectively [SEC grading is 1-7, where 1 is the highest]. The Friedman test was used to compare the mean difficulty rating scores provided for the difficulty of each topic. The mean difficulty rating score ranges from 1 to 4, where the larger the mean rating score, the higher the difficulty. When considering the whole group of students, nine topics out of 21 were perceived as significantly more difficult than the other topics. Protein synthesis, DNA Replication and Biomolecules were the most difficult, in that order. The Mann-Whitney U test revealed that the perceived level of difficulty in comprehending Biomolecules is significantly lower for students taking Chemistry compared to those not choosing the subject (p = 0.018). Protein Synthesis was claimed as the most difficult by Chemistry students and Biomolecules by those not studying Chemistry. DNA Replication was the second most difficult topic perceived by both groups. The Mann-Whitney U test was used to examine the effect of gender on the perceived level of difficulty in comprehending various topics. It was found that females have significantly more difficulty in comprehending Biomolecules than males (p=0.039). Protein synthesis was perceived as the most difficult topic by males (mean difficulty rating score = 3.14), while Biomolecules, DNA Replication and Protein synthesis were of equal difficulty for females (mean difficulty rating score = 3.00). Males and females perceived DNA Replication as equally difficult (mean difficulty rating score = 3.00). Discovering the students’ study habits and perceived level of difficulty of specific topics is vital for the lecturer to offer guidance that leads to higher academic achievement.

Keywords: biology, perceived difficulty, post-secondary, study habits

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6510 A Study on Household Food Security and Dietary Diversity in Urban Centers of Thrissur

Authors: Sandra Thomas

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This study tries to analyse the level of food security and dietary diversity among households of different socio-economic classes in the urban centers of Thrissur. The study revealed that there is no much difference in purchasing patterns of food articles among the socio-economic classes indicating a very high level of both physical and economic accessibility of food. On analysing the dietary diversity of the households none of the households scored below five and fifty-three per cent of the households scored eleven or twelve indicating higher diversity in diet. It was also found that income and education are the two important factors that influence the level of household food security.

Keywords: food security, dietary diversity, household level, socio-economic classes

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6509 Evaluation of Polyphenolics Compounds in Cold Brewed Indian Tea

Authors: Chandrima Das, Sirshendu Chatterjee

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Tea (Camellia sinensis) is known as nature's low calorie wonder drink. Since ancient times hot consumptions of tea is very much popular. We have observed that many heat sensitive secondary metabolites which get destroyed on heating, moreover by people, who are permanently live at higher altitude or the members of high altitude expedition team, are deprived of various tea brewing facilities like electricity, fuel, etc. and the hence cold decoction of tea might be a good alternative. In this backdrop present study aims at the analysis of antioxidants like polyphenols, flavonoids and free radical scavenging activity as well as the l-theanine concentration of different types of cold brewed teas like black, green, white and oolong and compared with its hot decoction. Further, we also analysed in details about the bioactive components by using HPLC followed by green synthesis of nanoparticles. The study highlighted that the difference between the concentration of antioxidant in cold and hot brewed tea is insignificant and hence intake of cold decoction will be beneficial to health.

Keywords: antioxidants, flavanoid, polyphenols, HPLC, nanoparticles

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6508 Combined Power Supply at Well Drilling in Extreme Climate Conditions

Authors: V. Morenov, E. Leusheva

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Power supplying of well drilling on oil and gas fields at ambient air low temperatures is characterized by increased requirements of electric and heat energy. Power costs for heating of production facilities, technological and living objects may several times exceed drilling equipment electric power consumption. Power supplying of prospecting and exploitation drilling objects is usually done by means of local electric power structures based on diesel power stations. In the meantime, exploitation of oil fields is accompanied by vast quantities of extracted associated petroleum gas, and while developing gas fields there are considerable amounts of natural gas and gas condensate. In this regard implementation of gas-powered self-sufficient power units functioning on produced crude products for power supplying is seen as most potential. For these purposes gas turbines (GT) or gas reciprocating engines (GRE) may be used. In addition gas-powered units are most efficiently used in cogeneration mode - combined heat and power production. Conducted research revealed that GT generate more heat than GRE while producing electricity. One of the latest GT design are microturbines (MT) - devices that may be efficiently exploited in combined heat and power mode. In conditions of ambient air low temperatures and high velocity wind sufficient heat supplying is required for both technological process, specifically for drilling mud heating, and for maintaining comfortable working conditions at the rig. One of the main heat regime parameters are the heat losses. Due to structural peculiarities of the rig most of the heat losses occur at cold air infiltration through the technological apertures and hatchways and heat transition of isolation constructions. Also significant amount of heat is required for working temperature sustaining of the drilling mud. Violation of circulation thermal regime may lead to ice build-up on well surfaces and ice blockages in armature elements. That is why it is important to ensure heating of the drilling mud chamber according to ambient air temperature. Needed heat power will be defined by heat losses of the chamber. Noting heat power required for drilling structure functioning, it is possible to create combined heat and power complex based on MT for satisfying consumer power needs and at the same time lowering power generation costs. As a result, combined power supplying scheme for multiple well drilling utilizing heat of MT flue gases was developed.

Keywords: combined heat, combined power, drilling, electric supply, gas-powered units, heat supply

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6507 A Comparison of Methods for Estimating Dichotomous Treatment Effects: A Simulation Study

Authors: Jacqueline Y. Thompson, Sam Watson, Lee Middleton, Karla Hemming

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Introduction: The odds ratio (estimated via logistic regression) is a well-established and common approach for estimating covariate-adjusted binary treatment effects when comparing a treatment and control group with dichotomous outcomes. Its popularity is primarily because of its stability and robustness to model misspecification. However, the situation is different for the relative risk and risk difference, which are arguably easier to interpret and better suited to specific designs such as non-inferiority studies. So far, there is no equivalent, widely acceptable approach to estimate an adjusted relative risk and risk difference when conducting clinical trials. This is partly due to the lack of a comprehensive evaluation of available candidate methods. Methods/Approach: A simulation study is designed to evaluate the performance of relevant candidate methods to estimate relative risks to represent conditional and marginal estimation approaches. We consider the log-binomial, generalised linear models (GLM) with iteratively weighted least-squares (IWLS) and model-based standard errors (SE); log-binomial GLM with convex optimisation and model-based SEs; log-binomial GLM with convex optimisation and permutation tests; modified-Poisson GLM IWLS and robust SEs; log-binomial generalised estimation equations (GEE) and robust SEs; marginal standardisation and delta method SEs; and marginal standardisation and permutation test SEs. Independent and identically distributed datasets are simulated from a randomised controlled trial to evaluate these candidate methods. Simulations are replicated 10000 times for each scenario across all possible combinations of sample sizes (200, 1000, and 5000), outcomes (10%, 50%, and 80%), and covariates (ranging from -0.05 to 0.7) representing weak, moderate or strong relationships. Treatment effects (ranging from 0, -0.5, 1; on the log-scale) will consider null (H0) and alternative (H1) hypotheses to evaluate coverage and power in realistic scenarios. Performance measures (bias, mean square error (MSE), relative efficiency, and convergence rates) are evaluated across scenarios covering a range of sample sizes, event rates, covariate prognostic strength, and model misspecifications. Potential Results, Relevance & Impact: There are several methods for estimating unadjusted and adjusted relative risks. However, it is unclear which method(s) is the most efficient, preserves type-I error rate, is robust to model misspecification, or is the most powerful when adjusting for non-prognostic and prognostic covariates. GEE estimations may be biased when the outcome distributions are not from marginal binary data. Also, it seems that marginal standardisation and convex optimisation may perform better than GLM IWLS log-binomial.

Keywords: binary outcomes, statistical methods, clinical trials, simulation study

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6506 Pentosan Polysulfate Sodium: A Potential Treatment to Improve Bone and Joint Manifestations of Mucopolysaccharidosis I

Authors: Drago Bratkovic, Curtis Gravance, David Ketteridge, Ravi Krishnan, Michael Imperiale

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The mucopolysaccharidoses (MPSs) are a group of lysosomal storage diseases that have a common defect in the catabolism of glycosaminoglycans (GAGs). MPS I is the most common of the MPS diseases. Manifestations of MPS I include coarsening of facial features, corneal clouding, developmental delay, short stature, skeletal manifestations, hearing loss, cardiac valve disease, hepatosplenomegaly, and umbilical and inguinal hernias. Treatments for MPS I restore or activate the missing or deficient enzyme in the case of enzyme replacement therapy (ERT) and haematopoietic stem cell transplantation (HSCT). Pentosan polysulfate sodium (PPS) is a potential treatment to improve bone and joint manifestations of MPS I. The mechanisms of action of PPS that are relevant to the treatment of MPS I are the ability to: (i) Reduce systemic and accumulated GAG, (ii) Reduce inflammatory effects via the inhibition of NF-kB, resulting in the reduction in pro-inflammatory mediators. (iii) Reduce the expression of the pain mediator nerve growth factor in osteocytes from degenerating joints. (iv) Inhibit the cartilage degrading enzymes related to joint dysfunction in MPS I. PPS is being evaluated as an adjunctive therapy to ERT and/or HSCT in an open-label, single-centre, phase 2 study. Patients are ≥ 5 years of age with a diagnosis of MPS I and previously received HSCT and/or ERT. Three white, female, patients with MPS I-Hurler, ages 14, 15, and 19 years, and one, white male patient aged 15 years are enrolled. All were diagnosed at ≤2 years of age. All patients received HSCT ≤ 6 months after diagnosis. Two of the patients were treated with ERT prior to HSCT, and 1 patient received ERT commencing 3 months prior to HSCT. Two patients received 0.75mg/kg and 2 patients received 1.5mg/kg of PPS. PPS was well tolerated at doses of 0.75 and 1.5 mg/kg to 47 weeks of continuous dosing. Of the 19 adverse events (AEs), 2 were related to PPS. One AE was moderate (pre-syncope) and 1 was mild (injection site bruising), experienced in the same patient. All AEs were reported as mild or moderate. There have been no SAEs. One subject experienced a COVID-19 infection and PPS was interrupted. The MPS I signature GAG fragments, sulfated disaccharide and UA-HNAc S, tended to decrease in 3 patients from baseline through Week 25. Week 25 GAG data are pending for the 4th patient. Overall, most biomarkers (inflammatory, cartilage degeneration, and bone turnover) evaluated in the 3 patients with 25-week assessments have indicated either no change or a reduction in levels compared to baseline. In 3 patients, there was a trend toward improvement in the 2MWT from baseline to Week 48 with > 100% increase in 1 patient (01-201). In the 3 patients that had Week 48 assessments, patients and proxies reported improvement in PGIC, including “worthwhile difference” (n=1), or “made all the difference” (n=2).

Keywords: MPS I, pentosan polysulfate sodium, clinical study, 2MWT, QoL

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6505 Modeling and Prediction of Zinc Extraction Efficiency from Concentrate by Operating Condition and Using Artificial Neural Networks

Authors: S. Mousavian, D. Ashouri, F. Mousavian, V. Nikkhah Rashidabad, N. Ghazinia

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PH, temperature, and time of extraction of each stage, agitation speed, and delay time between stages effect on efficiency of zinc extraction from concentrate. In this research, efficiency of zinc extraction was predicted as a function of mentioned variable by artificial neural networks (ANN). ANN with different layer was employed and the result show that the networks with 8 neurons in hidden layer has good agreement with experimental data.

Keywords: zinc extraction, efficiency, neural networks, operating condition

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6504 Cleaning of Polycyclic Aromatic Hydrocarbons (PAH) Obtained from Ferroalloys Plant

Authors: Stefan Andersson, Balram Panjwani, Bernd Wittgens, Jan Erik Olsen

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Polycyclic Aromatic hydrocarbons are organic compounds consisting of only hydrogen and carbon aromatic rings. PAH are neutral, non-polar molecules that are produced due to incomplete combustion of organic matter. These compounds are carcinogenic and interact with biological nucleophiles to inhibit the normal metabolic functions of the cells. Norways, the most important sources of PAH pollution is considered to be aluminum plants, the metallurgical industry, offshore oil activity, transport, and wood burning. Stricter governmental regulations regarding emissions to the outer and internal environment combined with increased awareness of the potential health effects have motivated Norwegian metal industries to increase their efforts to reduce emissions considerably. One of the objective of the ongoing industry and Norwegian research council supported "SCORE" project is to reduce potential PAH emissions from an off gas stream of a ferroalloy furnace through controlled combustion. In a dedicated combustion chamber. The sizing and configuration of the combustion chamber depends on the combined properties of the bulk gas stream and the properties of the PAH itself. In order to achieve efficient and complete combustion the residence time and minimum temperature need to be optimized. For this design approach reliable kinetic data of the individual PAH-species and/or groups thereof are necessary. However, kinetic data on the combustion of PAH are difficult to obtain and there is only a limited number of studies. The paper presents an evaluation of the kinetic data for some of the PAH obtained from literature. In the present study, the oxidation is modelled for pure PAH and also for PAH mixed with process gas. Using a perfectly stirred reactor modelling approach the oxidation is modelled including advanced reaction kinetics to study influence of residence time and temperature on the conversion of PAH to CO2 and water. A Chemical Reactor Network (CRN) approach is developed to understand the oxidation of PAH inside the combustion chamber. Chemical reactor network modeling has been found to be a valuable tool in the evaluation of oxidation behavior of PAH under various conditions.

Keywords: PAH, PSR, energy recovery, ferro alloy furnace

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6503 Gender Differences In Pain Assessment: A Daily Activities Perspective

Authors: Hui-mei Huang, Huei-Jiun Cheng

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Introduction Many patients are aware of the health benefits associated with an active lifestyle, but they are often hindered from engaging in physical activity due to the presence of pain. The majority of patients experience pain, which can fluctuate over time and is influenced by various factors, including gender. Gender differences in clinical pain and pain-related conditions are widely recognized. Existing literature strongly supports the notion that men and women exhibit distinct responses to pain. Previous studies conducted in Taiwan have highlighted gender differences in pain assessment, but only a limited number of studies have investigated the gender-related factors that influence pain during daily activities. The objective of this study was to examine gender differences in pain assessment among inpatients in Taiwan and investigate whether gender and surgical procedures are factors that impact the daily activities of pain. Method In this study, a prospective and structured questionnaire survey method was utilized, employing intentional sampling to gather data from inpatients admitted to a medical center in central Taiwan. The research period covered in this study is from October 1, 2019, to June 30, 2020. In this study, participants who were hospitalized within 48 hours were requested to self-assess their pain using the Numeric Rating Scale (NRS) and indicate the impact of pain on their activities. The data were analyzed to explore the potential influence of gender and surgical procedures on daily activities affected by pain. Result A total of 722 cases were included in the study, with the mean age of the subjects is 54.38 years old (SD=16.3), and the range varied from 18 to 93 years old. Among the subjects, 48.23% (n=348) were male, and 62.3% (n=450) of them had received more than 12 years of education., and 56.9% (n=411) underwent surgery. The results indicated that regardless of whether the participants underwent surgery or not, females experienced higher perceived severe pain intensity than males (t=2.248, P < .05). However, in surgical patients, there was no significant difference in gender (t=1.75, P > .05). Regarding the impact of pain on daily activities when pain intensity reached 7 , male subjects experienced a 5-point effect on their daily activities (AUC=0.84, 95% CI 0.79-0.89, P <0.01), while female subjects experienced a 7-point effect (AUC=0.88, 95% CI 0.80-0.87, P <0.01). Discussion Some studies suggest that women experience painful stimuli as more intense than men, this difference has been observed in various types of experimental pain, including mechanical and thermal stimuli. Our study reached the same conclusion, female patients exhibited greater intensity of pain. According to the research findings, The research findings highlight the significant impact of gender on individuals' response to intense pain (NRS>7) during their daily activities, with men showing a higher pain tolerance. The higher pain tolerance often observed in men may be attributed to societal conditioning, which encourages them to conceal outward expressions of pain. Further research in this area could help provide a more comprehensive understanding of the topic in Taiwan.

Keywords: pain assessment, gender, surgery, activities of daily living

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