Search results for: acquired ability to enact lethal self-injury

Authors: Fatiha Mohammed Arab, Benoit Augier, Francois Deniset, Pascal Casari, Jacques Andre Astolfi

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For the top high performance foiling yachts, cavitation is often a limiting factor for take-off and top speed. This work investigates solutions to delay the onset of cavitation thanks to structural morphing. The structural morphing is based on compliant leading and trailing edge, with effect similar to flaps. It is shown here that the commonly accepted effect of flaps regarding the control of lift and drag forces can also be used to postpone the inception of cavitation. A numerical and experimental study is conducted in order to assess the effect of the geometric parameters of hydrofoil on their hydrodynamic performances and in cavitation inception. The effect of a 70% trailing edge and a 30% leading edge of NACA 0012 is investigated using Xfoil software at a constant Reynolds number 106. The simulations carried out for a range flaps deflections and various angles of attack. So, the result showed that the lift coefficient increase with the increase of flap deflection, but also with the increase of angle of attack and enlarged the bucket cavitation. To evaluate the efficiency of the Xfoil software, a 2D analysis flow over a NACA 0012 with leading and trailing edge flap was studied using Fluent software. The results of the two methods are in a good agreement. To validate the numerical approach, a passive adaptive composite model is built and tested in the hydrodynamic tunnel at the Research Institute of French Naval Academy. The model shows the ability to simulate the effect of flap by a LE and TE structural morphing due to hydrodynamic loading.

Keywords: cavitation, flaps, hydrofoil, panel method, xfoil

Procedia PDF Downloads 171

Authors: Nokubonga G. Zulu, Bongephiwe M. Thethwayo, Mapilane S. Madiba, Peter A. Olubambi

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In South Africa, PGMs’ metallurgy industry is now leaned on the Upper Group 2 (UG2) reef for the beneficiation of 4PGEs (Platinum, Palladium, Rhodium, and Ruthenium). The current effective beneficiation method is direct froth flotation which uses the hydrophobicity of liberated valuables minerals to carefully float them while hydrophilic gangue minerals report to the residue. PGMs are known to be associated with base metal sulphides which are hydrophobic; however, approximately 25% of PGMs from UG2 are associated with hydrophilic silicates, which results in high PGMs grade in the flotation residue. Further, the smallest size in which UG2 PGMs occur is approximately 9 microns which demands high grinding for liberation, imposing energy and cost implications. The use of Bacillus mucilaginosus to liberate PGMs using Bio-leaching of PGMs bearing Silicates is a promising cost-effective, energy-saving, and green solution to liberate PGMs locked in silicates. This is due to the ability of Bacillus mucilaginosus to generate extracellular polysaccharides (EPS) that are responsible for the leaching of silicate minerals. The bioleaching is done at a laboratory beaker using a cultivated Bacillus mucilaginosus as a lixiviant. The bioleaching residue is expected to have a reduced particle size due to silicate consumption, which reduces the need and cost associated with a secondary milling circuit. Moreover, the grade of the bioleaching product is increased since the silicates (gangue minerals) are consumed by Bacillus mucilaginosus; this serves as a pre-concentration step. This paper discusses an alternative liberation and pre-concentrating technique of PGMs that are associated with silicates using Bacillus mucilaginosus leaching to dissolve silicates.

Keywords: Bacillus mucilaginosus, bio-leaching of PGMs bearing silicates, liberation of PGMs, pre-concentration of PGMs

Procedia PDF Downloads 125

Authors: H. Aksas, H. Babaci, K. Louhab

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In this paper, a comparative study of the adsorption of Chromium and dyes, onto mixture biosorbents, olive stones and date pits at different percentage was investigated in aqueous solution. The study of various parameters: Effect of contact time, pH, temperature and initial concentration shows that these materials possess a high affinity for the adsorption of chromium for the adsorption of dye bezaktiv yellow HE-4G. To deepen the comparative study of the adsorption of chromium and dye with the use of different blends of olive stones and date pits, the following models are studied: Langmuir, Freundlich isotherms and Dubinin- Radushkvich (D-R) were used as the adsorption equilibrium data model. Langmuir isotherm model was the most suitable for the adsorption of the dye bezaktiv HE-4G and the D-R model is most suitable for adsorption Chrome. The pseudo-first-order model, pseudo-second order and intraparticle diffusion were used to describe the adsorption kinetics. The apparent activation energy was found to be less than 8KJ/mol, which is characteristic of a controlled chemical reaction for the adsorption of two materials. t was noticed that adsorption of chromium and dye BEZAKTIV HE-YELLOW 4G follows the kinetics of the pseudo second order. The study of the effect of temperature was quantified by calculating various thermodynamic parameters such as Gibbs free energy, enthalpy and entropy changes. The resulting thermodynamic parameters indicate the endothermic nature of the adsorption of Cr (VI) ions and the dye Bezaktiv HE-4G. But these materials are very good adsorbents, as they represent a low cost. in addition, it has been noticed that the greater the quantity of olive stone in the mixture increases, the adsorption ability of the dye or chromium increases.

Keywords: chromium ions, anions dye, sorption, mixed adsorbents, olive stone, date pits

Procedia PDF Downloads 225

Authors: Yuxiao Jiang, Lingjun Meng, Mengyu Zhan, Lichunyi Zhang, Yingxia Yun

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On August 8th of 2015, a serious explosion occurred in Binhai New Area of Tianjin. This explosion led to the suspension of Tianjin-Binhai Light Rail Line 9 which was an important transportation mean connecting the old and new urban areas and the suspension causes inconvenience to commuters traveling from Tianjin to Binhai or Binhai to Tianjin and residents living by Line 9. On this regard, this paper intends to give suggestions on how to develop multi-mode transportation system rapidly and effectively after a disaster and tackle with the problems in terms of transportation infrastructure facilities. The paper proposes the idea of traffic resilience which refers to the city’s ability to restore its transportation system and reduce risks when the transportation system is destroyed by a disaster. By doing questionnaire research, on the spot study and collecting data from the internet, a GIS model is established so as to analyze the alternative traffic means used by different types of residents and study the transportation supply and demand. The result shows that along the Line 9, there is a larger demand for alternative traffic means in the place which is nearer to the downtown area. Also, the distribution of bus stations is more reasonable in the place nearer to downtown area, however, the traffic speed in the area is slower. Based on traffic resilience, the paper raises strategies to develop post-disaster multi-mode transportation system such as establishing traffic management mechanism timely and effectively, building multi-mode traffic networks, improving intelligent traffic systems and so on.

Keywords: traffic resilience, multi-mode transportation system, public traffic, transportation demand

Procedia PDF Downloads 340

Authors: Paolo Grazioli

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In this paper, we present the main results achieved during an eight-week international design project on Colorado Future Sustainable Mobilitycarried out at Metropolitan State University of Denver. The project was born with the intention to seize the opportunity created by the Colorado government’s plan to promote e-bikes mobility by creating a large network of dedicated tracks. The project was supported by local entrepreneurs who offered financial and professional support. The main goal of the project was to engage design students with the skills to design a user-centered, original vehicle that would satisfy the unarticulated practical and emotional needs of “Gen Z” users by creating a fun, useful, and reliablelife companion that would helps users carry out their everyday tasks in a practical and enjoyable way. The project was carried out with the intention of proving the importance of the combination of creative methods with practical design methodologies towards the creation of an innovative yet immediately manufacturable product for a more sustainable future. The final results demonstrate the students' capability to create innovative and yet manufacturable products and, especially, their ability to create a new design paradigm for future sustainable mobility products. The design solutions explored n the project include collaborative learning and human-interaction design for future mobility. The findings of the research led students to the fabrication of two working prototypes that will be tested in Colorado and developed for manufacturing in the year 2024. The project showed that collaborative design and project-based teaching improve the quality of the outcome and can lead to the creation of real life, innovative products directly from the classroom to the market.

Keywords: sustainable transportation design, interface design, collaborative design, user -centered design research, design prototyping

Procedia PDF Downloads 92

Authors: Kara Terki Ibtissem, Hassaine Hafida, Bellifa Samia

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Introduction: Staphylococcus aureus is one of the species that are most frequently isolated from urinary catheters. The ability to produce a biofilm is an important step in the pathogenesis of these staphylococci; biofilm formation is strongly dependent on the environmental conditions it also depends on the different parameters these biofilms are subjected to. Antiseptics, including ethanol and betadine, are used in clinical practice for disinfection and infection prevention. Recent studies, however, demonstrate that disinfectants may enhance biofilm production in Staphylococci. Methods: In this study, 48 staphylococcus aureus isolated from urinary catheters at the University Hospital Center of Sidi Bel Abbes (in Northwestern Algeria) were analyzed to detect the formation of biofilm by culture on Red Congo Agar (RCA), the Tube Method (TM) and tissue Culture Plate (TCP) techniques, this last was also used to investigate the effect of ethanol and Betadine on the preformed biofilm In a second time to know which environment is most favorable to the formation of the biofilm we perform a statistical test based on the student test by the software R. Results: It has been found that 23 strains produced a bacterial slime on the Congo red medium, 5 strains produced a biofilm by the tube method, 2 of which are highly productive. In addition, 7 strains produced a biofilm on polystyrene micro-plates; this number was higher in the presence of ethanol 70% and ethanol 90% with 19 and 11 biofilm-producing strains, respectively. On the other hand, no biofilm was formed in the presence of Betadine. Conclusion: It is important to examine the response of biofilms following an imposed external constraint, such as disinfectants, in order to develop new strategies to combat bacterial biofilms but also to better control their formation.

Keywords: staphylococcus aureus, biofilm, urinary catheter, ethanol

Procedia PDF Downloads 53

Authors: Sergio Tovar-Pérez, Sebastian Töpfer, Markus Gräfe

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The work proposes a technique that decreases the detection acquisition time of quantum holography schemes down to one-third; this allows the possibility to image moving objects. Since its invention, quantum holography with undetected photon schemes has gained interest in the scientific community. This is mainly due to its ability to tailor the detected wavelengths according to the needs of the scheme implementation. Yet this wavelength flexibility grants the scheme a wide range of possible applications; an important matter was yet to be addressed. Since the scheme uses digital phase-shifting techniques to retrieve the information of the object out of the interference pattern, it is necessary to acquire a set of at least four images of the interference pattern along with well-defined phase steps to recover the full object information. Hence, the imaging method requires larger acquisition times to produce well-resolved images. As a consequence, the measurement of moving objects remains out of the reach of the imaging scheme. This work presents the use and implementation of a spatial light modulator along with a digital holographic technique called quasi-parallel phase-shifting. This technique uses the spatial light modulator to build a structured phase image consisting of a chessboard pattern containing the different phase steps for digitally calculating the object information. Depending on the reduction in the number of needed frames, the acquisition time reduces by a significant factor. This technique opens the door to the implementation of the scheme for moving objects. In particular, the application of this scheme in imaging alive specimens comes one step closer.

Keywords: quasi-parallel phase shifting, quantum imaging, quantum holography, quantum metrology

Procedia PDF Downloads 106

Authors: HU Changjuan, Gong Cong, Long Hao

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Although urban ecological policies and the public's aspiration for livable environments have expedited the pace of ecological revitalization, historic districts that have evolved through natural ecological processes often become obsolete and less habitable amid rapid urbanization. This raises a critical question about historic districts inherently incapable of being ecological and livable. The thriving concept of ‘intrinsic ecology,’ characterized by its ability to transform city-district systems into healthy ecosystems with diverse environments, stable functions, and rapid restoration capabilities, holds potential for guiding the integration of ancient and modern ecological wisdom while supporting the dynamic involvement of cultures. This study explores the intrinsic ecology of historic districts from three aspects: 1) Population Density: By comparing the population density before urban population expansion to the present day, determine the reasonable population density for historic districts. 2) Building Density: Using the ‘Space-mate’ tool for comparative analysis, form a spatial matrix to explore the intrinsic ecology of building density in Chinese historic districts. 3) Green Capacity Ratio: By using ecological districts as control samples, conduct dual comparative analyses (related comparison and upgraded comparison) to determine the intrinsic ecological advantages of the two-dimensional and three-dimensional green volume in historic districts. The study inform a density optimization strategy that supports cultural, social, natural, and economic ecology, contributing to the creation of eco-historic districts.

Keywords: eco-historic districts, intrinsic ecology, suitable density, green capacity ratio.

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Authors: Oscar Covarrubias, Diane Ghanem, Christopher Murdock, Babar Shafiq

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Introduction: ChatGPT is an advanced language AI tool designed to understand and generate human-like text. The aim of this study is to assess the ability of ChatGPT-4 to re-write orthopaedic trauma patient education materials at the recommended 6th-grade level. Methods: Two independent reviewers accessed ChatGPT-4 (chat.openai.com) and gave identical instructions to simplify the readability of provided text to a 6th-grade level. All trauma-related articles by the Orthopaedic Trauma Association (OTA) and American Academy of Orthopaedic Surgeons (AAOS) were sequentially provided. The academic grade level was determined using the Flesh-Kincaid Grade Level (FKGL) and Flesch Reading Ease (FRE). Paired t-tests and Wilcox-rank sum tests were used to compare the FKGL and FRE between the ChatGPT-4 revised and original text. Inter-rater correlation coefficient (ICC) was used to assess variability in ChatGPT-4 generated text between the two reviewers. Results: ChatGPT-4 significantly reduced FKGL and increased FRE scores in the OTA (FKGL: 5.7±0.5 compared to the original 8.2±1.1, FRE: 76.4±5.7 compared to the original 65.5±6.6, p < 0.001) and AAOS articles (FKGL: 5.8±0.8 compared to the original 8.9±0.8, FRE: 76±5.5 compared to the original 56.7±5.9, p < 0.001). On average, 14.6% of OTA and 28.6% of AAOS articles required at least two revisions by ChatGPT-4 to achieve a 6th-grade reading level. ICC demonstrated poor reliability for FKGL (OTA 0.24, AAOS 0.45) and moderate reliability for FRE (OTA 0.61, AAOS 0.73). Conclusion: This study provides a novel, simple and efficient method using language AI to optimize the readability of patient education content which may only require the surgeon’s final proofreading. This method would likely be as effective for other medical specialties.

Keywords: artificial intelligence, AI, chatGPT, patient education, readability, trauma education

Procedia PDF Downloads 69

Authors: N. Bourayou, A. -H. Meniai, A. Gouaoura

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The presence of salt can either raise or lower the distribution coefficient of a solute acetic acid in liquid- liquid equilibria. The coefficient of solute is defined as the ratio of the composition of solute in solvent rich phase to the composition of solute in diluents (water) rich phase. The phenomena are known as salting–out or salting-in, respectively. The effect of monovalent salt, sodium chloride and the bivalent salt, sodium sulfate on the distribution of acetic acid between 1-butanol and water at 298.15K were experimentally shown to be effective in modifying the liquid-liquid equilibrium of water/acetic acid/1-butanol system in favour of the solvent extraction of acetic acid from an aqueous solution with 1-butanol, particularly at high salt concentrations of both salts. All the two salts studied are found to have to salt out effect for acetic acid in varying degrees. The experimentally measured data were well correlated by Eisen-Joffe equation. NRTL model for solvent mixtures containing salts was able to provide good correlation of the present liquid-liquid equilibrium data. Using the regressed salt concentration coefficients for the salt-solvent interaction parameters and the solvent-solvent interaction parameters obtained from the same system without salt. The calculated phase equilibrium was in a quite good agreement with the experimental data, showing the ability of NRTL model to correlate salt effect on the liquid-liquid equilibrium.

Keywords: activity coefficient, Eisen-Joffe, NRTL model, sodium chloride

Procedia PDF Downloads 275

Authors: Alma Khasenovna Zhakina, Arnt Oxana Vasilievna, Vasilets Evgeny Petrovich

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The aim of this project is to develop methods for obtaining new molecularly imprinted polymers from coal waste to study their structure, structural and morphological features and properties. Recently, the development of molecularly imprinted polymers has become one of the hot topics for researchers. Modern research indicates the broad prospects of rapidly developing molecular imprinting technologies for creating a new generation of sorption materials. The attractiveness of this area of research lies in the fact that the use of imprinted polymers is not limited to scientific research; they are already being introduced in the chemical, pharmaceutical and biotechnological industries, primarily at the stages of purification of the final product. For the use of molecularly imprinted polymers in the development of sorption material, their ability to selectively remove pollutants, including trace concentrations, is of fundamental importance, and the exceptional stability of polymeric materials under harsh conditions makes it possible to simplify the process of water purification as a whole. The scientific and technical effect is associated with the development of technologies for the production of new molecularly imprinted polymers, the establishment of optimal conditions for their production and the creation of effective imprinted sorbents on their basis for wastewater treatment from heavy metals. The social effect is due to the fact that the use of coal waste as a feedstock for the production of imprinted sorbents will make it possible in the future to create new industries with additional jobs and obtain competitive multi-purpose products. The economic and multiplier effect is associated with the low cost of the final product due to the involvement of local coal waste in the production, reduction of transport, customs and other costs.

Keywords: imprinted polymers, coal waste, polymerization, template, customized sorbents

Procedia PDF Downloads 60

Authors: Suphalucksana, Wichai, Sangsoponjit Settasit, Soytong Kasem

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A study on the efficiency for enzyme production of fungi isolated from stomach of buffalo was conducted. The fungi were collected from 4 parts of stomach as rumen, reticulum, omasum and abomasums. The objective to study the efficiency of fungi from stomach of buffalo had effected to produced enzyme and to selected fungi for their ability to produced enzyme cellulase, hemicellulase and ligninase. Results shown that the fungi isolated from rumen were: Eupenicillium sp. (B-RU-01-1), Eupenicillium sp. (B-RU-02-3G), Rhyzopus stolonifer (B-RU-01-4) and Trichoderma sp. (B-RU-01-2). From the reticulum, Aspergillus glaucus (B-RET-02-3), Aspergillus orchraceus (B-RET-02-2) and Penicillium sp. (B-RET-02-4) were found. In the omasum Aspergillus fumigatus (B-OMA-01-1G), Eurotium sp. (B-OMA-01-4) and Rhizopus stolonifer (B-OMA-02-3) were isolated and in the abomasums Aspergillus flavas (B-ABO-02-3), Aspergillus fumigatus (B-ABO-02-1), Aspergillus niger (B-ABO-01-3G), Aspergillius terreus (B-ABO-02-4) and Mucor sp. (B-ABO-02-4G). Results of enzyme analysis revealed that cellulase was produced by isolated: Eupenicillium sp. (B-RU-02-3G), Eupenicillium sp. (B-RU-01-1), Penicillium sp. (B-RET-02-4), Aspergillius glaucus (B-RET-02-3), Aspergillus ochraceus (B-RET-02-2), Aspergillius fumigatus (B-OMA-01-1G), Eurotium sp. (B-OMA-01-4), Aspergillius flavus (B-ABO-02-3), Aspergillius fumigatus (B-ABO-02-1), Aspergillius niger (B-ABO-01-3G), Aspergillius terreus (B-ABO-02-4). Hemicellulase was produced Eupenicillium sp. (B-RU-02-3G), Eupenicillium sp. (B-RU-01-1), Rhizopus stolonifer (B-RU-01-4), Trichoderma sp. (B-RU-01-2), Aspergillius glaucus (B-RET-02-3), Aspergillus ochraceus (B-RET-02-2), Penicillium sp. (B-RET-02-4), Aspergillius fumigatus (B-OMA-01-1G), Eurotium sp. (B-OMA -01-4), Aspergillius flavus (B-ABO-02-3), Aspergillius fumigatus (B-ABO-02-1) Aspergillius niger (B-ABO-01-3G), Aspergillius terreus (B-ABO-02-4), Mucor sp. (B-ABO-02-4G). For the enzyme ligninase, two isolates were found to produced this enzyme namely : Trichoderma sp. (B-RU-01-2) and Mucor sp. (B-ABO-02-4G).

Keywords: enzyme production from fungi, enzyme production, fungi, agricultural technology

Procedia PDF Downloads 383

Authors: Núria Arimany Serrat, Xavier Ferràs Hernández, Petra A. Nylund, Eric Viardot

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Innovation is an increasingly important antecedent to firm competitiveness and growth. Successful innovation, however, requires a significant financial commitment and the means of financing accessible to the firm may affect its ability to innovate. The access to equity financing such as venture capital has been connected to innovativeness for young firms. For established enterprises, debt financing of innovation may be a more realistic option. Continuous innovation and growth would otherwise require a constant increase of equity. We, therefore, investigate the relation between debt financing and innovation for large firms and hypothesize that those firms that carry more debt will be more innovative. The need for debt financing of innovation may be reduced for very profitable firms, which can finance innovation with cash flow. We thus hypothesize a moderating effect of profitability on the relationship between debt financing and innovation. We carry out an empirical investigation using a longitudinal data set including 167 large European firms over five years, resulting in 835 firm years. We apply generalized least squares (GLS) regression with fixed firm effects to control for firm heterogeneity. The findings support our hypotheses and we conclude that access to debt finding is an important antecedent of innovation, with profitability as a moderating factor. The results do however differ across national innovation systems and we find a strong relationship for British, Dutch, French, and Italian firms but not for German and Spanish entities. We discuss differences in the national systems of innovation and financing which contextualize the variations in the findings and thus make a nuanced contribution to the research in innovation financing. The cross-country differences calls for differentiated advice to managers, institutions, and researchers depending on the national context.

Keywords: innovation, R&D, national innovation systems, financing

Procedia PDF Downloads 527

Authors: Md. Belal Uudin Rabbi, Sakib Al Montasir, Saifur Rahman, Niger Nahid, Esmail Hossain Emon

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The practice of radiation shielding protects against the detrimental effects of ionizing radiation. Radiation shielding depletes radiation by inserting a shield of absorbing material between any radioactive source. It is a primary concern when building several industrial fields, so using potent (high activity) radioisotopes in food preservation, cancer treatment, and particle accelerator facilities is significant. Radiation shielding is essential for radiation-emitting equipment users to reduce or mitigate radiation damage. Polymer composites (especially epoxy based) with high atomic number fillers can replace toxic Lead in ionizing radiation shielding applications because of their excellent mechanical properties, superior solvent and chemical resistance, good dimensional stability, adhesive, and less toxic. Due to being lightweight, good neutron shielding ability in almost the same order as concrete, epoxy-based radiation shielding can be the next big thing. Micro and nano-particles for the epoxy resin increase the epoxy matrix's radiation shielding property. Shielding is required to protect users of such facilities from ionizing radiation as recently, and considerable attention has been paid to polymeric composites as a radiation shielding material. This research will examine the radiation shielding performance of epoxy-based nano-WO3 reinforced composites, exploring the performance of epoxy-based nano-WO3 reinforced composites. The samples will be prepared using the direct pouring method to block radiation. The practice of radiation shielding protects against the detrimental effects of ionizing radiation.

Keywords: radiation shielding materials, ionizing radiation, epoxy resin, Tungsten oxide, polymer composites

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Authors: M. Yazdani, J. F. Carragher

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Citrus gall wasp (CGW), Bruchophagus fellis (Hym: Eurytomidae), is an Australian native insect pest. CGW has now become a problem of national concern, threatening the viability of the entire Australian citrus industry. However, CGW appears to exhibit a preference for certain citrus species; growers report that grapefruit and lemons are most severely infested, with oranges and mandarins affected to a lesser extent. Given the specificity of the host plant-insect interactions, it is speculated that plant volatiles may play a significant role in host recognition. To address whether plant volatiles is involved in host plant preference by CGW we tested the behavioral response of CGW to plants in a wind tunnel. The result showed that CGW had significantly higher preference to grapefruit and lemon than other cultivars and the least preference was recorded to mandarin (Chi-square test, P<0.001). Because CGW exhibited a detectable choice further studies were undertaken to identify the components of the volatiles from each species. We trapped the volatile chemicals emitted by a 30 cm tip of each plant onto a solid Porapak matrix. Eluted extracts were then analysed by Gas Chromatography-Mass Spectrometry (GCMS) and the presumptive identity of the major compounds from each species inferred from the MS library. Although the same major compounds existed in all of the cultivars, the relative ratios of them differed between species. Next, we will validate the identity of the key volatiles using authentic standards and establish their ability to elicit olfactory responses in CGW in wind tunnel and field experiments. Identification of semiochemicals involved in host location by CGW is of interest not only from an ecological perspective but also for the development of novel pest control strategies.

Keywords: Citrus gall wasp, Bruchophagus fellis, volatiles, semiochemicals, IPM

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Authors: Risna Wijayanti, Sumiati, Hanif Iswari

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This study aims to analyze the role of financial risk attitude as a mediation between financial knowledge and business growth. The ability of human resources in managing capital (financial literacy) can be a major milestone for a company's business to grow and build its competitive advantage. This study analyzed the important role of financial risk attitude in bringing about financial knowledge on corporate growth. There have been many discussions arguing that financial knowledge is one of the main abilities of corporate managers in determining the success of managing a company. However, a contrary argument of other scholars also enlightened that financial knowledge did not have a significant influence on corporate growth. This study used literatures' review to analyze whether there is another variable that can mediate the effect of financial knowledge toward corporate growth. Research mapping was conducted to analyze the concept of risk tolerance. This concept was related to people's risk aversion effects when making a decision under risk and the role of financial knowledge on changes in financial income. Understanding and managing risks and investments are complicated, in particular for corporate managers, who are always demanded to maintain their corporate growth. Substantial financial knowledge is extremely needed to identify and take accurate information for corporate financial decision-making. By reviewing several literature, this study hypothesized that financial knowledge of corporate managers would be meaningless without manager's courage to bear risks for taking favorable business opportunities. Therefore, the level of risk aversion from corporate managers will determine corporate action, which is a reflection of corporate-level investment behavior leading to attain corporate success or failure for achieving the company's expected growth rate.

Keywords: financial knowledge, financial risk attitude, corporate growth, risk tolerance

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Authors: Xingyu Gao, Qiang Wu, Yuanyuan Liu, Yue Yang

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In the era of the knowledge economy, the relationship between scientific knowledge and patents has garnered significant attention. Understanding the intricate interplay between the foundations of science and technological innovation has emerged as a pivotal challenge for both researchers and policymakers. This study establishes a coupled network of artificial intelligence patents based on co-cited scientific papers. Leveraging centrality metrics from network analysis offers a fresh perspective on understanding the influence of information flow and knowledge sharing within the network on patent impact. The study initially obtained patent numbers for 446,890 granted US AI patents from the United States Patent and Trademark Office’s artificial intelligence patent database for the years 2002-2020. Subsequently, specific information regarding these patents was acquired using the Lens patent retrieval platform. Additionally, a search and deduplication process was performed on scientific non-patent references (SNPRs) using the Web of Science database, resulting in the selection of 184,603 patents that cited 37,467 unique SNPRs. Finally, this study constructs a coupled network comprising 59,379 artificial intelligence patents by utilizing scientific papers co-cited in patent backward citations. In this network, nodes represent patents, and if patents reference the same scientific papers, connections are established between them, serving as edges within the network. Nodes and edges collectively constitute the patent coupling network. Structural characteristics such as node degree centrality, betweenness centrality, and closeness centrality are employed to assess the scientific connections between patents, while citation count is utilized as a quantitative metric for patent influence. Finally, a negative binomial model is employed to test the nonlinear relationship between these network structural features and patent influence. The research findings indicate that network structural features such as node degree centrality, betweenness centrality, and closeness centrality exhibit inverted U-shaped relationships with patent influence. Specifically, as these centrality metrics increase, patent influence initially shows an upward trend, but once these features reach a certain threshold, patent influence starts to decline. This discovery suggests that moderate network centrality is beneficial for enhancing patent influence, while excessively high centrality may have a detrimental effect on patent influence. This finding offers crucial insights for policymakers, emphasizing the importance of encouraging moderate knowledge flow and sharing to promote innovation when formulating technology policies. It suggests that in certain situations, data sharing and integration can contribute to innovation. Consequently, policymakers can take measures to promote data-sharing policies, such as open data initiatives, to facilitate the flow of knowledge and the generation of innovation. Additionally, governments and relevant agencies can achieve broader knowledge dissemination by supporting collaborative research projects, adjusting intellectual property policies to enhance flexibility, or nurturing technology entrepreneurship ecosystems.

Keywords: centrality, patent coupling network, patent influence, social network analysis

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Authors: Nabeel Abdulkadhim Athab

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The purpose of this research is to conduct a comparative study according analysis of programmed to some of physical and mechanical variables for joint wrist injury. As it can be through this research to distinguish between the amount of variation in the work of the joint after sample underwent rehabilitation program to improve the effectiveness of the joint and naturally restore its effectiveness. Supposed researcher that there is statistically significant differences between the results of the tests pre and post the members research sample, as a result of submission the sample to the program of rehabilitation, which led to the development of muscle activity that are working on wrist joint and this is what led to note the differences between the results of the tests pre and post. The researcher used the descriptive method. The research sample included (6) of injured players in the wrist joint, as the average age (21.68) and standard deviation (1.13) either length average (178cm) and standard deviation (2.08). And the sample as evidenced homogeneous among themselves. And where the data were collected, introduced in program for statistical processing to get to the most important conclusions and recommendations and that the most important: 1-The commitment of the sample program the qualifying process variables studied in the search for the heterogeneity of study activity and effectiveness of wrist joint for injured players. 2-The analysis programmed a high accuracy in the measurement of the research variables, and which led to the possibility of discrimination into account differences in motor ability camel and injured in the wrist joint. To search recommendations including: 1-The use of computer systems in the scientific research for the possibility of obtaining accurate research results. 2-Programming exercises rehabilitation according to an expert system for possible use by patients without reference to the person processor.

Keywords: analysis of joint wrist injury, physical and mechanical variables, wrist joint, wrist injury

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Authors: Bernardita Tornero

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Cognitive Acceleration in Mathematics Education (CAME) programmes have been used successfully for promoting the development of thinking skills in school students for the last 30 years. Given that the approach has had a tremendous impact on the thinking capabilities of participating students, this study explored the experience of using the programme with prospective primary teachers in Chile. Therefore, this study not only looked at the experience of prospective primary teachers during the CAME course as learners, but also examined how they perceived the approach from their perspective as future teachers, as well as how they could transfer the teaching strategies they observed to their future classrooms. Given the complexity of the phenomenon under study, this research used a mixed methods approach. For this reason, the impact that the CAME course had on prospective teachers’ thinking skills was not only approached by using a test that assessed the participants’ improvements in these skills, but their learning and teaching experiences were also recorded through qualitative research tools (learning journals, interviews and field notes). The main findings indicate that, at the end of the CAME course, prospective teachers not only demonstrated higher thinking levels, but also showed positive attitudinal changes towards teaching and learning in general, and towards mathematics in particular. The participants also had increased confidence in their ability to teach mathematics and to promote thinking skills in their students. In terms of the CAME methodology, prospective teachers not only found it novel and motivating, but also commented that dealing with the thinking skills topic during a university course was both unusual and very important for their professional development. This study also showed that, at the end of the CAME course, prospective teachers felt they had developed strategies that could be used in their classrooms in the future. In this context, the relevance of the study is not only that it described the impact and the positive results of the first experience of using a CAME approach with prospective teachers, but also that some of the conclusions have significant implications for the teaching of thinking skills and the training of primary school teachers.

Keywords: cognitive acceleration, formal reasoning, prospective teachers, initial teacher training

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Authors: Clara Shenderey, Helena Vitoshkin, Mordechai Barak, Avraham Arbel

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Greenhouse cultivation is an energy-intensive process due to the high demands on cooling or heating according to external climatic conditions, which could be extreme in the summer or winter seasons. The thermal radiation rate inside a greenhouse depends mainly on the type of covering material and greenhouse construction. Using additional thermal screens under a greenhouse covering combined with a dehumidification system improves the insulation and could be cost-effective. Greenhouse covering material usually contains protective ultraviolet (UV) radiation additives to prevent the film wear, insect harm, and crop diseases. This paper investigates the overall heat transfer coefficient, or U-value, for greenhouse polyethylene covering contains UV-additives and glass covering with or without a thermal screen supplement. The hot-box method was employed to evaluate overall heat transfer coefficients experimentally as a function of the type and number of the thermal screens. The results show that the overall heat transfer coefficient decreases with increasing the number of thermal screens as a hyperbolic function. The overall heat transfer coefficient highly depends on the ability of the material to reflect thermal radiation. Using a greenhouse covering, i.e., polyethylene films or glass, in combination with high reflective thermal screens, i.e., containing about 98% of aluminum stripes or aluminum foil, the U-value reduces by 61%-89% in the first case, whereas by 70%-92% in the second case, depending on the number of the thermal screen. Using thermal screens made from low reflective materials may reduce the U-value by 30%-57%. The heat transfer coefficient is an indicator of the thermal insulation properties of the materials, which allows farmers to make decisions on the use of appropriate thermal screens depending on the external and internal climate conditions in a greenhouse.

Keywords: energy-saving thermal screen, greenhouse cover material, heat transfer coefficient, hot box

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Authors: Ahmed Elaksher, Islam Omar

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Accurate geometric relation algorithms are imperative in Earth and planetary satellite and aerial image processing, particularly for high-resolution images that are used for topographic mapping. Most of these satellites carry push-broom sensors. These sensors are optical scanners equipped with linear arrays of CCDs. These sensors have been deployed on most EOSs. In addition, the LROC is equipped with two push NACs that provide 0.5 meter-scale panchromatic images over a 5 km swath of the Moon. The HiRISE carried by the MRO and the HRSC carried by MEX are examples of push-broom sensor that produces images of the surface of Mars. Sensor models developed in photogrammetry relate image space coordinates in two or more images with the 3D coordinates of ground features. Rigorous sensor models use the actual interior orientation parameters and exterior orientation parameters of the camera, unlike approximate models. In this research, we generate a generic push-broom sensor model to process imageries acquired through linear array cameras and investigate its performance, advantages, and disadvantages in generating topographic models for the Earth, Mars, and the Moon. We also compare and contrast the utilization, effectiveness, and applicability of available photogrammetric techniques and softcopies with the developed model. We start by defining an image reference coordinate system to unify image coordinates from all three arrays. The transformation from an image coordinate system to a reference coordinate system involves a translation and three rotations. For any image point within the linear array, its image reference coordinates, the coordinates of the exposure center of the array in the ground coordinate system at the imaging epoch (t), and the corresponding ground point coordinates are related through the collinearity condition that states that all these three points must be on the same line. The rotation angles for each CCD array at the epoch t are defined and included in the transformation model. The exterior orientation parameters of an image line, i.e., coordinates of exposure station and rotation angles, are computed by a polynomial interpolation function in time (t). The parameter (t) is the time at a certain epoch from a certain orbit position. Depending on the types of observations, coordinates, and parameters may be treated as knowns or unknowns differently in various situations. The unknown coefficients are determined in a bundle adjustment. The orientation process starts by extracting the sensor position and, orientation and raw images from the PDS. The parameters of each image line are then estimated and imported into the push-broom sensor model. We also define tie points between image pairs to aid the bundle adjustment model, determine the refined camera parameters, and generate highly accurate topographic maps. The model was tested on different satellite images such as IKONOS, QuickBird, and WorldView-2, HiRISE. It was found that the accuracy of our model is comparable to those of commercial and open-source software, the computational efficiency of the developed model is high, the model could be used in different environments with various sensors, and the implementation process is much more cost-and effort-consuming.

Keywords: photogrammetry, push-broom sensors, IKONOS, HiRISE, collinearity condition

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Authors: Rana Mohamed, Ahmed E. Gomaa, Gehan Safwat, Ayman Diab

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Background: Bio-fabrication is a multidisciplinary research field that combines several principles, fabrication techniques, and protocols from different fields. The open-source-software movement is a movement that supports the use of open-source licenses for some or all software as part of the broader notion of open collaboration. Additive manufacturing is the concept of 3D printing, where it is a manufacturing method through adding layer-by-layer using computer-aided designs (CAD). There are several types of AM system used, and they can be categorized by the type of process used. One of these AM technologies is Digital light processing (DLP) which is a 3D printing technology used to rapidly cure a photopolymer resin to create hard scaffolds. DLP uses a projected light source to cure (Harden or crosslinking) the entire layer at once. Current applications of DLP are focused on dental and medical applications. Other developments have been made in this field, leading to the revolutionary field 3D bioprinting. The open-source movement was started to spread the concept of open-source software to provide software or hardware that is cheaper, reliable, and has better quality. Objective: Modification of desktop 3D printer into 3D bio-printer and the integration of DLP technology and bio-fabrication to produce an antibacterial dental model. Method: Modification of a desktop 3D printer into a 3D bioprinter. Gelatin hydrogel and sodium alginate hydrogel were prepared with different concentrations. Rhizome of Zingiber officinale, Flower buds of Syzygium aromaticum, and Bulbs of Allium sativum were extracted, and extractions were selected on different levels (Powder, aqueous extracts, total oils, and Essential oils) prepared for antibacterial bioactivity. Agar well diffusion method along with the E. coli have been used to perform the sensitivity test for the antibacterial activity of the extracts acquired by Zingiber officinale, Syzygium aromaticum, and Allium sativum. Lastly, DLP printing was performed to produce several dental models with the natural extracted combined with hydrogel to represent and simulate the Hard and Soft tissues. Result: The desktop 3D printer was modified into 3D bioprinter using open-source software Marline and modified custom-made 3D printed parts. Sodium alginate hydrogel and gelatin hydrogel were prepared at 5% (w/v), 10% (w/v), and 15%(w/v). Resin integration with the natural extracts of Rhizome of Zingiber officinale, Flower buds of Syzygium aromaticum, and Bulbs of Allium sativum was done following the percentage 1- 3% for each extract. Finally, the Antimicrobial dental model was printed; exhibits the antimicrobial activity, followed by merging with sodium alginate hydrogel. Conclusion: The open-source movement was successful in modifying and producing a low-cost Desktop 3D Bioprinter showing the potential of further enhancement in such scope. Additionally, the potential of integrating the DLP technology with bioprinting is a promising step toward the usage of the antimicrobial activity using natural products.

Keywords: 3D printing, 3D bio-printing, DLP, hydrogel, antibacterial activity, zingiber officinale, syzygium aromaticum, allium sativum, panax ginseng, dental applications

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Authors: John Lloyd Angolluan, Jennile Caday, Crystal Mae Estrella, Reike Alliyah Taladua, Zion Michael Ysulat

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One of the requirements of having the ability to communicate in English is by having adequate vocabulary. Nowadays, people are more engaged in watching movie streams on which they can watch movies in a very portable way, such as Netflix. Wherein Netflix became global demand for online media has taken off in recent years. This research aims to know whether the use of bimodal subtitles on Netflix English movies can enhance vocabulary. This study is quantitative and utilizes a descriptive method, and this study aims to explore the use of bimodal subtitles on Netflix English movies to enhance the vocabulary of students. The respondents of the study were the selected Second-year English majors of Rizal Technological University Pasig and Boni Campus using the purposive sampling technique. The researcher conducted a survey questionnaire through the use of Google Forms. In this study, the weighted mean was used to evaluate the student's responses to the statement of the problems of the study of the use of bimodal subtitles on Netflix English movies. The findings of this study revealed that the bimodal subtitle on Netflix English movies enhanced students’ vocabulary learning acquisition by providing learners with access to large amounts of real and comprehensible language input, whether accidentally or intentionally, and it turns out that bimodal subtitles on Netflix English movies help students recognize vocabulary, which has a positive impact on their vocabulary building. Therefore, the researchers advocate that watching English Netflix movies enhances students' vocabulary by using bimodal subtitled movie material during their language learning process, which may increase their motivation and the usage of bimodal subtitles in learning new vocabulary. Bimodal subtitles need to be incorporated into educational film activities to provide students with a vast amount of input to expand their vocabulary.

Keywords: bimodal subtitles, Netflix, English movies, vocabulary, subtitle, language, media

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Authors: Sohayla Khaled El Fakahany

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Cultural and structural limitations and conservative social norms have direct effects on the availability of sources of sexual and reproductive health and rights (SRHR) in the Arab Region. Nevertheless, SRHR advocates, healthcare providers, and organizations have created online spaces like websites, blogs, and social media platforms to increase people’s access and ability to share information, experiences, and services. While these efforts help increase the accessibility to information and services, they also create and reflect inequalities based on limited internet access. Furthermore, these emergent ways of sharing and raising awareness online cannot be seen as a substitute for the urgent need for public healthcare systems and services to address SRHR issues in Arab states. This research aims to analyze the impact of the increasing importance of the role of social media platforms and technologies in the dissemination of SRHR-related information online to the youth as well as the associated inequalities of access. It also seeks to assess the effects and inequalities of the dependence on online platforms, which should be complementary to public and private SRHR services. The theoretical framework adopts Asef Bayat’s concept of social non-movements to analyze how collective mobilization around SRHR issues is exercised in repressive and conservative settings in the Arab region. Using digital ethnography of four prominent digital platforms and a qualitative survey of people aged 18-30 years, the research draws attention to the urgent need for better access to knowledge and services around gender, bodily autonomy, and sexual and reproductive health in the Arab region.

Keywords: sexual and reproductive health and rights, social non-movements, digital platforms, Arab region

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Authors: Qing Wu, Xuchun Ye, Qiuchen Wang, Kirsten Corazzini

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Objective: It’s increasing acknowledged that patient engagement in healthcare and health literacy both have positive impact on patient outcome. Health literacy emphasizes the ability of individuals to understand and apply health information and manage health. Patients' health literacy affected their willingness to participate in decision-making, but its impact on the behavior and willingness of patient engagement in healthcare is not clear, especially in China. Therefore, this study aimed to explore the correlation between the behavior and willingness of patient engagement and health literacy. Methods: A cross-sectional survey was employed using the behavior and willingness of patient engagement in healthcare questionnaire, Chinese version All Aspects of Health Literacy Scale (AAHLS). A convenient sample of 443 patients was recruited from 8 general hospitals in Shanghai, Jiangsu Province and Zhejiang Province, from September 2016 to January 2017. Results: The mean score for the willingness was (4.41±0.45), and the mean score for the patient engagement behavior was (4.17±0.49); the mean score for the patient's health literacy was (2.36±0.29)，the average score of its three dimensions- the functional literacy, the Communicative/interactive literacy and the Critical literacy, was (2.26±0.38), (2.28±0.42), and (2.61±0.43), respectively. Patients' health literacy was positively correlated with their willingness of engagement (r = 0.367, P < 0.01), and positively correlated with patient engagement behavior (r = 0.357, P < 0.01). All dimensions of health literacy were positively correlated with the behavior and willingness of patient engagement in healthcare; the dimension of Communicative/interactive literacy (r = 0.312, P < 0.01; r = 0.357, P < 0.01) and the Critical literacy (r = 0.357, P < 0.01; r = 0.357, P < 0.01) are more relevant to the behavior and willingness than the dimension of basic/functional literacy (r=0.150, P < 0.01; r = 0.150, P < 0.01). Conclusions: The behavior and willingness of patient engagement in healthcare are positively correlated with health literacy and its dimensions. In clinical work, medical staff should pay attention to patients’ health literacy, especially the situation that low literacy leads to low participation and provide health information to patients through health education or communication to improve their health literacy as well as guide them to actively and rationally participate in their own health care.

Keywords: patient engagement, health literacy, healthcare, correlation

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Authors: Priyanwada I. Singhapathirana

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The public land ownership is a common phenomenon in many countries in the world however, the development approaches and the institutional structures are greatly diverse. The existing scholarship around public land development has been greatly limited to Europe and advanced Asian economies. Inferences of such studies seem to be inadequate and inappropriate to comprehend the peculiarities of public land development in developing Asian economies. The absence of critical inquiry on the public land ownership and the long-established institutional structures which govern the development has restrained these countries from institutional innovations. In this context, this research investigates the issues related to public land development and the institutional responses in Sri Lanka. This study introduces the concept of ‘Institutional Responsiveness’ in Public land development, which is conceptualized as the ability of the institutions to respond to the spatial, market and fiscal stimulus. The inquiry was carried out through in-depth interviews with five key informants from apex public agencies in order to explore the responsiveness of land institutions form decision-makers' perspectives. Further, the analysis of grey literature and recent media reports are used to supplement the analysis. As per the findings, long term abandonment of public lands and high transaction costs are some of the key issues in relation to public land development. The inability of the institutions to respond to the market and fiscal stimulus has left many potential public lands underutilized. As a result, the public sector itself and urban citizens have not been able to relish the benefits of the public lands in cities. Spatial analysis at the local scale is suggested for future studies in order to capture the multiple dimensions of the responsiveness of institutions to the development stimulus.

Keywords: institutions, public land, responsiveness, under-utilization

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Authors: Piotr Kunecki, Magdalena Wdowin

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The fly ash produced as waste in the process of conventional coal combustion was utilized in the hybrid synthesis of zeolites X and A from Faujasite (FAU) and Linde Type A (LTA) frameworks, respectively. The applied synthesis method included modification together with the crystallization stage. The sorbent modification was performed by introducing metals into the zeolite structure in order to create an ability to form stable bonds with elemental mercury (Hg0). The use of waste in the form of fly ash as a source of silicon and aluminum, as well as the proposed method of zeolite synthesis, fits the circular economy idea. The effect of zeolite modification on Hg0 removal from a simulated gas stream was studied empirically using prototype installation designed to test the effectiveness of sorption by solid-state sorbents. Both derived zeolites X and A modified with silver nitrate revealed significant mercury uptake during a 150-minute sorption experiment. The amount of elemental mercury removed in the experiment ranged from 5.69 to 6.01 µg Hg0/1g of sorbent for zeolites X and from 4.47 to 4.86 µg Hg0/1g of sorbent for zeolites A. In order to confirm the effectiveness of the sorbents towards mercury bonding, the possible re-emission effect was tested as well. Derived zeolites X and A did not show mercury re-emission after the sorption process, which confirms the stable bonding of Hg0 in the structure of synthesized zeolites. The proposed hybrid synthesis method possesses the potential to be implemented for both fly ash utilization as well as the time and energy-saving production of aluminosilicate, porous materials with high Hg0 removal efficiency. This research was supported by National Science Centre, Poland, grant no 2021/41/N/ST5/03214.

Keywords: fly ash, synthetic zeolites, elemental mercury removal, sorption, simulated gas stream

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Authors: Amenah Galo, Mohammed Farid, Kareem Alsharkawy, Robert Warner, Karthikeyan Srinivasan, Haitham Khalil, Ruth Waters

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Introduction: The cessation of elective surgery, particularly breast reconstruction, continue to be affected by the COVID-19 pandemic. The restructuring of medical services and staff redeployment severely affected the ability to return to normality for surgical specialties. The aim of this study is to determine the decline in breast reconstruction affected by the COVID-19 pandemic in a tertiary center. Methods: A retrospective review of breast reconstruction cases (autologous, non-autologous) or mastectomies Pre- COVID (March 2019-March 2020) and during COVID (March 2020- March 2021) at Queen Elizabeth Hospital, Birmingham, were collated. Data included patient demographics, BMI, previous and recent reconstruction, length of hospital stay, and mastectomies, including risk-reducing. Results: The number of patients who had breast reconstruction was significantly lower during COVID (n=62) compared to pre-COVID (n=199). The mean age (pre-COVID 51, COVID 59 years), BMI (Pre-COVID and COVID = 27), previous reconstruction (pre-COVID n=101, 51%, COVID n=33, 53%) and length hospital stay was less during COVID (3 days) compared to Pre-COVID (4 days). The proportion of risk-reducing mastectomies and reconstruction during COVID (32%, n=20) were higher than pre-COVID (21%, n=41). A higher proportion rate of autologous reconstruction (DIEP 56, TRAM 17) Pre-COVID compared to COVID (DIEP 22, TRAM 7). Implant reconstructions were higher during COVID (n=19, 31%) than pre-COVID (n=31, 16%). Conclusion: The lack of regular provision for breast reconstruction continues to decline during the pandemic. This will have a tremendous impact on waiting lists without a timeline for reconstruction to offer patients. An international survey highlights the disparities in offering breast reconstruction and strategies to rectify this issue.

Keywords: breast reconstruction, COVID-19 pandemic, mastectomy, autologous, implant

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Authors: MyungGu Yeo, JongHan Ha, Gi-Hoon Yang, JaeYoon Lee, SeungHyun Ahn, Hyeongjin Lee, HoJun Jeon, YongBok Kim, Minseong Kim, GeunHyung Kim

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Tissue engineering is a rapidly growing interdisciplinary research area that may provide options for treating damaged tissues and organs. As a promising technique for regenerating various tissues, this technology requires biomedical scaffolds, which serve as an artificial extracellular matrix (ECM) to support neotissue growth. Electrospun micro/nanofibers have been used widely in tissue engineering because of their high surface-area-to-volume ratio and structural similarity to extracellular matrix. However, low mechanical sustainability, low 3D shape-ability, and low cell infiltration have been major limitations to their use. In this work, we propose new hybrid scaffolds interlayered with cell-laden electrospun micro/nano fibers and poly(caprolactone) microstructures. Also, we applied various concentrations of alginate and electric field strengths to determine optimal conditions for the cell-electrospinning process. The combination of cell-laden bioink (2 ⅹ 10^5 osteoblast-like MG63 cells/mL, 2 wt% alginate, 2 wt% poly(ethylene oxide), and 0.7 wt% lecithin) and a 0.16 kV/mm electric field showed the highest cell viability and fiber formation in this process. Using these conditions and PCL microstructures, we achieved mechanically stable hybrid scaffolds. In addition, the cells embedded in the fibrous structure were viable and proliferated. We suggest that the cell-embedded hybrid scaffolds fabricated using the cell-electrospinning process may be useful for various soft- and hard-tissue regeneration applications.

Keywords: bioink, cell-laden scaffold, micro/nanofibers, poly(caprolactone)

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Authors: Stefan Gruden, Charlott Brunmark, Bo Holmqvist, Erwin D. Brenndorfer, Martin Johansson, Jian Liu, Ying Zhao, Niklas Axen, Moustapha Hassan

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Aim: The study was designed to evaluate the ability of the calcium sulfate-based NanoZolid® drug delivery technology to locally release the epidermal growth factor (EGF) protein while maintaining its biological activity. Methods: NanoZolid-formulated EGF protein labelled with a near-infrared dye (EGF-NIR) depots or EGF-NIR dissolved in PBS were injected subcutaneously into mice bearing EGF receptor (EGFR) positive human A549 lung cancer tumors inoculated subcutaneously. The release and biodistribution of the EGF-NIR were investigated in vivo longitudinally up to 96 hours post-administration, utilizing whole-body fluorescence imaging. In order to confirm the in vivo findings, histological analysis of tumor cryosections was performed to investigate EGF-NIR fluorescent signal and EGFR expression level by immunofluorescence labelling. Results: The in vivo fluorescence imaging showed a controlled release profile of the EGF-NIR loaded in the NanoZolid depots compared to free EGF-NIR. Histological analysis of the tumors further demonstrated a prevailing distribution of EGF-NIR in regions with high levels of EGFR expression. Conclusion: Calcium sulfate based depots can be used to formulate EGF while maintaining its biological activity, e.g., receptor binding capability. This may have good clinical potential for local delivery of biomolecules to enhance treatment efficacy and minimize systemic adverse effects.

Keywords: bioresorbable, calcium sulfate, controlled release, NanoZolid

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