Search results for: elastic foundation
Commenced in January 2007
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Edition: International
Paper Count: 2043

Search results for: elastic foundation

243 Variation of Biologically Active Compounds and Antioxidancy in the Process of Blueberry Storage

Authors: Meri Khakhutaishvili, Indira Djaparidze, Maia Vanidze, Aleko Kalandia

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Cultivation of blueberry in Georgia started in 21st century. There are more than 20 species of blueberry cultivated in this region from all other the world. The species are mostly planted on acidic soil, previously occupied by tea plantations. Many of the plantations have pretty good yield. It is known that changing the location of a plant to a new soil or climate effects chemical compositions of the plant. However, even though these plants are brought from other countries, no research has been conducted to fully examine the blueberry fruit cultivated in Georgia. Shota Rustaveli National Science Foundation Grant FR/335/10-160/14, gave us an opportunity to continue our previous works and conduct research on several berries, among them of course the chemical composition of stored Blueberry. We were able to conduct the first study that included examining qualitative and quantitative features of bioactive compounds in Georgian Blueberry. This experiments were held in the ‘West Georgia Regional Chromatography center’ (Grant AP/96/13) of our university, that is equipped with modern equipment like HPLC UV-Vis, RI-detector, HPLC-conductivity detector, UPLC-MS-detector. Biochemical analysis was conducted using different physico-chemical and instrumental methods. Separation-identification and quantitative analysis were conducted using UPLC-MS (Waters Acquity QDa detector), HPLC (Waters Brceze 1525, UV-Vis 2489 detectors), pH-meters (Mettler Toledo). Refractrometer -Misco , Spectrometer –Cuvette Changer (Mettler Toledo UV5A), C18 Cartridge Solid Phase Extraction (SPE) Waters Sep-Pak C18 (500 mg), Chemicals – stability radical- 2,2-Diphenil-1-picrilhydrazyl (Aldrich-germany), Acetonitrile, Methanol, Acetic Acid (Merck-Germany), AlCl3, Folin Ciocalteu reagent (preparation), Standarts –Callic acid, Quercetin. Carbohydrate HPLC-RI analysis used systems acetonitrile-water (80-20). UPLC-MS analysis used systems- solvent A- Water +1 % acetic acid და solvent -B Methanol +1% acetic acid). It was concluded that the amount of sugars was in range of 5-9 %, mostly glucose and fructose. Also, the amount of organic acids was 0.2-1.2% most of which was malic and citric acid. Anthocians were also present in the sample 200-550mg/100g. We were able to identify up to 15 different compounds, most of which were products of delphinidine and cyanide. All species have high antioxidant level(DPPH). By rapidly freezing the sample and then keeping it in specific conditions allowed us to keep the sample for 12 months.

Keywords: antioxidants, bioactive, blueberry, storage

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242 A Research on the Improvement of Small and Medium-Sized City in Early-Modern China (1895-1927): Taking Southern Jiangsu as an Example

Authors: Xiaoqiang Fu, Baihao Li

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In 1895, the failure of Sino-Japanese prompted the trend of comprehensive and systematic study of western pattern in China. In urban planning and construction, urban reform movement sprang up slowly, which aimed at renovating and reconstructing the traditional cities into modern cities similar to the concessions. During the movement, Chinese traditional city initiated a process of modern urban planning for its modernization. Meanwhile, the traditional planning morphology and system started to disintegrate, on the contrary, western form and technology had become the paradigm. Therefore, the improvement of existing cities had become the prototype of urban planning of early modern China. Currently, researches of the movement mainly concentrate on large cities, concessions, railway hub cities and some special cities resembling those. However, the systematic research about the large number of traditional small and medium-sized cities is still blank, up to now. This paper takes the improvement constructions of small and medium-sized cities in Southern region of Jiangsu Province as the research object. First of all, the criteria of small and medium-sized cities are based on the administrative levels of general office and cities at the county level. Secondly, the suitability of taking the Southern Jiangsu as the research object. The southern area of Jiangsu province called Southern Jiangsu for short, was the most economically developed region in Jiangsu, and also one of the most economically developed and the highest urbanization regions in China. As the most developed agricultural areas in ancient China, Southern Jiangsu formed a large number of traditional small and medium-sized cities. In early modern times, with the help of the Shanghai economic radiation, geographical advantage and powerful economic foundation, Southern Jiangsu became an important birthplace of Chinese national industry. Furthermore, the strong business atmosphere promoted the widespread urban improvement practices, which were incomparable of other regions. Meanwhile, the demonstration of Shanghai, Zhenjiang, Suzhou and other port cities became the improvement pattern of small and medium-sized city in Southern Jiangsu. This paper analyzes the reform movement of the small and medium-sized cities in Southern Jiangsu (1895-1927), including the subjects, objects, laws, technologies and the influence factors of politic and society, etc. At last, this paper reveals the formation mechanism and characteristics of urban improvement movement in early modern China. According to the paper, the improvement of small-medium city was a kind of gestation of the local city planning culture in early modern China,with a fusion of introduction and endophytism.

Keywords: early modern China, improvement of small-medium city, southern region of Jiangsu province, urban planning history of China

Procedia PDF Downloads 237
241 Agrowastes to Edible Hydrogels through Bio Nanotechnology Interventions: Bioactive from Mandarin Peels

Authors: Niharika Kaushal, Minni Singh

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Citrus fruits contain an abundance of phytochemicals that can promote health. A substantial amount of agrowaste is produced from the juice processing industries, primarily peels and seeds. This leftover agrowaste is a reservoir of nutraceuticals, particularly bioflavonoids which render it antioxidant and potentially anticancerous. It is, therefore, favorable to utilize this biomass and contribute towards sustainability in a manner that value-added products may be derived from them, nutraceuticals, in this study. However, the pre-systemic metabolism of flavonoids in the gastric phase limits the effectiveness of these bioflavonoids derived from mandarin biomass. In this study, ‘kinnow’ mandarin (Citrus nobilis X Citrus deliciosa) biomass was explored for its flavonoid profile. This work entails supercritical fluid extraction and identification of bioflavonoids from mandarin biomass. Furthermore, to overcome the limitations of these flavonoids in the gastrointestinal tract, a double-layered vehicular mechanism comprising the fabrication of nanoconjugates and edible hydrogels was adopted. Total flavonoids in the mandarin peel extract were estimated by the aluminum chloride complexation method and were found to be 47.3±1.06 mg/ml rutin equivalents as total flavonoids. Mass spectral analysis revealed the abundance of polymethoxyflavones (PMFs), nobiletin and tangeretin as the major flavonoids in the extract, followed by hesperetin and naringenin. Furthermore, the antioxidant potential was analyzed by the 2,2-diphenyl-1-picrylhydrazyl (DPPH) method, which showed an IC50 of 0.55μg/ml. Nanoconjugates were fabricated via the solvent evaporation method, which was further impregnated into hydrogels. Additionally, the release characteristics of nanoconjugate-laden hydrogels in a simulated gastrointestinal environment were studied. The PLGA-PMFs nanoconjugates exhibited a particle size between 200-250nm having a smooth and spherical shape as revealed by FE-SEM. The impregnated alginate hydrogels offered a dense network that ensured the holding of PLGA-PMF nanoconjugates, as confirmed by Cryo-SEM images. Rheological studies revealed the shear-thinning behavior of hydrogels and their high resistance to deformation. Gastrointestinal studies showed a negligible 4.0% release of flavonoids in the gastric phase, followed by a sustained release over the next hours in the intestinal environment. Therefore, based on the enormous potential of recovering nutraceuticals from agro-processing wastes, further augmented by nanotechnological interventions for enhancing the bioefficacy of these compounds, lays the foundation for exploring the path towards the development of value-added products, thereby contributing towards the sustainable use of agrowaste.

Keywords: agrowaste, gastrointestinal, hydrogel, nutraceuticals

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240 Quantification of Magnetic Resonance Elastography for Tissue Shear Modulus using U-Net Trained with Finite-Differential Time-Domain Simulation

Authors: Jiaying Zhang, Xin Mu, Chang Ni, Jeff L. Zhang

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Magnetic resonance elastography (MRE) non-invasively assesses tissue elastic properties, such as shear modulus, by measuring tissue’s displacement in response to mechanical waves. The estimated metrics on tissue elasticity or stiffness have been shown to be valuable for monitoring physiologic or pathophysiologic status of tissue, such as a tumor or fatty liver. To quantify tissue shear modulus from MRE-acquired displacements (essentially an inverse problem), multiple approaches have been proposed, including Local Frequency Estimation (LFE) and Direct Inversion (DI). However, one common problem with these methods is that the estimates are severely noise-sensitive due to either the inverse-problem nature or noise propagation in the pixel-by-pixel process. With the advent of deep learning (DL) and its promise in solving inverse problems, a few groups in the field of MRE have explored the feasibility of using DL methods for quantifying shear modulus from MRE data. Most of the groups chose to use real MRE data for DL model training and to cut training images into smaller patches, which enriches feature characteristics of training data but inevitably increases computation time and results in outcomes with patched patterns. In this study, simulated wave images generated by Finite Differential Time Domain (FDTD) simulation are used for network training, and U-Net is used to extract features from each training image without cutting it into patches. The use of simulated data for model training has the flexibility of customizing training datasets to match specific applications. The proposed method aimed to estimate tissue shear modulus from MRE data with high robustness to noise and high model-training efficiency. Specifically, a set of 3000 maps of shear modulus (with a range of 1 kPa to 15 kPa) containing randomly positioned objects were simulated, and their corresponding wave images were generated. The two types of data were fed into the training of a U-Net model as its output and input, respectively. For an independently simulated set of 1000 images, the performance of the proposed method against DI and LFE was compared by the relative errors (root mean square error or RMSE divided by averaged shear modulus) between the true shear modulus map and the estimated ones. The results showed that the estimated shear modulus by the proposed method achieved a relative error of 4.91%±0.66%, substantially lower than 78.20%±1.11% by LFE. Using simulated data, the proposed method significantly outperformed LFE and DI in resilience to increasing noise levels and in resolving fine changes of shear modulus. The feasibility of the proposed method was also tested on MRE data acquired from phantoms and from human calf muscles, resulting in maps of shear modulus with low noise. In future work, the method’s performance on phantom and its repeatability on human data will be tested in a more quantitative manner. In conclusion, the proposed method showed much promise in quantifying tissue shear modulus from MRE with high robustness and efficiency.

Keywords: deep learning, magnetic resonance elastography, magnetic resonance imaging, shear modulus estimation

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239 Characterization of Potato Starch/Guar Gum Composite Film Modified by Ecofriendly Cross-Linkers

Authors: Sujosh Nandi, Proshanta Guha

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Synthetic plastics are preferred for food packaging due to high strength, stretch-ability, good water vapor and gas barrier properties, transparency and low cost. However, environmental pollution generated by these synthetic plastics is a major concern of modern human civilization. Therefore, use of biodegradable polymers as a substitute for synthetic non-biodegradable polymers are encouraged to be used even after considering drawbacks related to mechanical and barrier properties of the films. Starch is considered one of the potential raw material for the biodegradable polymer, encounters poor water barrier property and mechanical properties due to its hydrophilic nature. That apart, recrystallization of starch molecules occurs during aging which decreases flexibility and increases elastic modulus of the film. The recrystallization process can be minimized by blending of other hydrocolloids having similar structural compatibility, into the starch matrix. Therefore, incorporation of guar gum having a similar structural backbone, into the starch matrix can introduce a potential film into the realm of biodegradable polymer. However, hydrophilic nature of both starch and guar gum, water barrier property of the film is low. One of the prospective solution to enhance this could be modification of the potato starch/guar gum (PSGG) composite film using cross-linker. Over the years, several cross-linking agents such as phosphorus oxychloride, sodium trimetaphosphate, etc. have been used to improve water vapor permeability (WVP) of the films. However, these chemical cross-linking agents are toxic, expensive and take longer time to degrade. Therefore, naturally available carboxylic acid (tartaric acid, malonic acid, succinic acid, etc.) had been used as a cross-linker and found that water barrier property enhanced substantially. As per our knowledge, no works have been reported with tartaric acid and succinic acid as a cross-linking agent blended with the PSGG films. Therefore, the objective of the present study was to examine the changes in water vapor barrier property and mechanical properties of the PSGG films after cross-linked with tartaric acid (TA) and succinic acid (SA). The cross-linkers were blended with PSGG film-forming solution at four different concentrations (4, 8, 12 & 16%) and cast on teflon plate at 37°C for 20 h. From the fourier-transform infrared spectroscopy (FTIR) study of the developed films, a band at 1720cm-1 was observed which is attributed to the formation of ester group in the developed films. On the other hand, it was observed that tensile strength (TS) of the cross-linked film decreased compared to non-cross linked films, whereas strain at break increased by several folds. Moreover, the results depicted that tensile strength diminished with increasing the concentration of TA or SA and lowest TS (1.62 MPa) was observed for 16% SA. That apart, maximum strain at break was also observed for TA at 16% and the reason behind this could be a lesser degree of crystallinity of the TA cross-linked films compared to SA. However, water vapor permeability of succinic acid cross-linked film was reduced significantly, but it was enhanced significantly by addition of tartaric acid.

Keywords: cross linking agent, guar gum, organic acids, potato starch

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238 Preschoolers’ Selective Trust in Moral Promises

Authors: Yuanxia Zheng, Min Zhong, Cong Xin, Guoxiong Liu, Liqi Zhu

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Trust is a critical foundation of social interaction and development, playing a significant role in the physical and mental well-being of children, as well as their social participation. Previous research has demonstrated that young children do not blindly trust others but make selective trust judgments based on available information. The characteristics of speakers can influence children’s trust judgments. According to Mayer et al.’s model of trust, these characteristics of speakers, including ability, benevolence, and integrity, can influence children’s trust judgments. While previous research has focused primarily on the effects of ability and benevolence, there has been relatively little attention paid to integrity, which refers to individuals’ adherence to promises, fairness, and justice. This study focuses specifically on how keeping/breaking promises affects young children’s trust judgments. The paradigm of selective trust was employed in two experiments. A sample size of 100 children was required for an effect size of w = 0.30,α = 0.05,1-β = 0.85, using G*Power 3.1. This study employed a 2×2 within-subjects design to investigate the effects of moral valence of promises (within-subjects factor: moral vs. immoral promises), and fulfilment of promises (within-subjects factor: kept vs. broken promises) on children’s trust judgments (divided into declarative and promising contexts). In Experiment 1 adapted binary choice paradigms, presenting 118 preschoolers (62 girls, Mean age = 4.99 years, SD = 0.78) with four conflict scenarios involving the keeping or breaking moral/immoral promises, in order to investigate children’s trust judgments. Experiment 2 utilized single choice paradigms, in which 112 preschoolers (57 girls, Mean age = 4.94 years, SD = 0.80) were presented four stories to examine their level of trust. The results of Experiment 1 showed that preschoolers selectively trusted both promisors who kept moral promises and those who broke immoral promises, as well as their assertions and new promises. Additionally, the 5.5-6.5-year-old children are more likely to trust both promisors who keep moral promises and those who break immoral promises more than the 3.5- 4.5-year-old children. Moreover, preschoolers are more likely to make accurate trust judgments towards promisor who kept moral promise compared to those who broke immoral promises. The results of Experiment 2 showed significant differences of preschoolers’ trust degree: kept moral promise > broke immoral promise > broke moral promise ≈ kept immoral promise. This study is the first to investigate the development of trust judgement in moral promise among preschoolers aged 3.5-6.5. The results show that preschoolers can consider both valence and fulfilment of promises when making trust judgments. Furthermore, as preschoolers mature, they become more inclined to trust promisors who keep moral promises and those who break immoral promises. Additionally, the study reveals that preschoolers have the highest level of trust in promisors who kept moral promises, followed by those who broke immoral promises. Promisors who broke moral promises and those who kept immoral promises are trusted the least. These findings contribute valuable insights to our understanding of moral promises and trust judgment.

Keywords: promise, trust, moral judgement, preschoolers

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237 Preparation of Biodegradable Methacrylic Nanoparticles by Semicontinuous Heterophase Polymerization for Drugs Loading: The Case of Acetylsalicylic Acid

Authors: J. Roberto Lopez, Hened Saade, Graciela Morales, Javier Enriquez, Raul G. Lopez

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Implementation of systems based on nanostructures for drug delivery applications have taken relevance in recent studies focused on biomedical applications. Although there are several nanostructures as drugs carriers, the use of polymeric nanoparticles (PNP) has been widely studied for this purpose, however, the main issue for these nanostructures is the size control below 50 nm with a narrow distribution size, due to they must go through different physiological barriers and avoid to be filtered by kidneys (< 10 nm) or the spleen (> 100 nm). Thus, considering these and other factors, it can be mentioned that drug-loaded nanostructures with sizes varying between 10 and 50 nm are preferred in the development and study of PNP/drugs systems. In this sense, the Semicontinuous Heterophase Polymerization (SHP) offers the possibility to obtain PNP in the desired size range. Considering the above explained, methacrylic copolymer nanoparticles were obtained under SHP. The reactions were carried out in a jacketed glass reactor with the required quantities of water, ammonium persulfate as initiator, sodium dodecyl sulfate/sodium dioctyl sulfosuccinate as surfactants, methyl methacrylate and methacrylic acid as monomers with molar ratio of 2/1, respectively. The monomer solution was dosed dropwise during reaction at 70 °C with a mechanical stirring of 650 rpm. Nanoparticles of poly(methyl methacrylate-co-methacrylic acid) were loaded with acetylsalicylic acid (ASA, aspirin) by a chemical adsorption technique. The purified latex was put in contact with a solution of ASA in dichloromethane (DCM) at 0.1, 0.2, 0.4 or 0.6 wt-%, at 35°C during 12 hours. According to the boiling point of DCM, as well as DCM and water densities, the loading process is completed when the whole DCM is evaporated. The hydrodynamic diameter was measured after polymerization by quasi-elastic light scattering and transmission electron microscopy, before and after loading procedures with ASA. The quantitative and qualitative analyses of PNP loaded with ASA were measured by infrared spectroscopy, differential scattering calorimetry and thermogravimetric analysis. Also, the molar mass distributions of polymers were determined in a gel permeation chromatograph apparatus. The load capacity and efficiency were determined by gravimetric analysis. The hydrodynamic diameter results for methacrylic PNP without ASA showed a narrow distribution with an average particle size around 10 nm and a composition methyl methacrylate/methacrylic acid molar ratio equal to 2/1, same composition of Eudragit S100, which is a commercial compound widely used as excipient. Moreover, the latex was stabilized in a relative high solids content (around 11 %), a monomer conversion almost 95 % and a number molecular weight around 400 Kg/mol. The average particle size in the PNP/aspirin systems fluctuated between 18 and 24 nm depending on the initial percentage of aspirin in the loading process, being the drug content as high as 24 % with an efficiency loading of 36 %. These average sizes results have not been reported in the literature, thus, the methacrylic nanoparticles here reported are capable to be loaded with a considerable amount of ASA and be used as a drug carrier.

Keywords: aspirin, biocompatibility, biodegradable, Eudragit S100, methacrylic nanoparticles

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236 Reaching the Goals of Routine HIV Screening Programs: Quantifying and Implementing an Effective HIV Screening System in Northern Nigeria Facilities Based on Optimal Volume Analysis

Authors: Folajinmi Oluwasina, Towolawi Adetayo, Kate Ssamula, Penninah Iutung, Daniel Reijer

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Objective: Routine HIV screening has been promoted as an essential component of efforts to reduce incidence, morbidity, and mortality. The objectives of this study were to identify the optimal annual volume needed to realize the public health goals of HIV screening in the AIDS Healthcare Foundation supported hospitals and establish an implementation process to realize that optimal annual volume. Methods: Starting in 2011 a program was established to routinize HIV screening within communities and government hospitals. In 2016 Five-years of HIV screening data were reviewed to identify the optimal annual proportions of age-eligible patients screened to realize the public health goals of reducing new diagnoses and ending late-stage diagnosis (tracked as concurrent HIV/AIDS diagnosis). Analysis demonstrated that rates of new diagnoses level off when 42% of age-eligible patients were screened, providing a baseline for routine screening efforts; and concurrent HIV/AIDS diagnoses reached statistical zero at screening rates of 70%. Annual facility based targets were re-structured to meet these new target volumes. Restructuring efforts focused on right-sizing HIV screening programs to align and transition programs to integrated HIV screening within standard medical care and treatment. Results: Over one million patients were screened for HIV during the five years; 16, 033 new HIV diagnoses and access to care and treatment made successfully for 82 % (13,206), and concurrent diagnosis rates went from 32.26% to 25.27%. While screening rates increased by 104.7% over the 5-years, volume analysis demonstrated that rates need to further increase by 62.52% to reach desired 20% baseline and more than double to reach optimal annual screening volume. In 2011 facility targets for HIV screening were increased to reflect volume analysis, and in that third year, 12 of the 19 facilities reached or exceeded new baseline targets. Conclusions and Recommendation: Quantifying targets against routine HIV screening goals identified optimal annual screening volume and allowed facilities to scale their program size and allocate resources accordingly. The program transitioned from utilizing non-evidence based annual volume increases to establishing annual targets based on optimal volume analysis. This has allowed efforts to be evaluated on the ability to realize quantified goals related to the public health value of HIV screening. Optimal volume analysis helps to determine the size of an HIV screening program. It is a public health tool, not a tool to determine if an individual patient should receive screening.

Keywords: HIV screening, optimal volume, HIV diagnosis, routine

Procedia PDF Downloads 239
235 First-Trimester Screening of Preeclampsia in a Routine Care

Authors: Tamar Grdzelishvili, Zaza Sinauridze

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Introduction: Preeclampsia is a complication of the second trimester of pregnancy, which is characterized by high morbidity and multiorgan damage. Many complex pathogenic mechanisms are now implicated to be responsible for this disease (1). Preeclampsia is one of the leading causes of maternal mortality worldwide. Statistics are enough to convince you of the seriousness of this pathology: about 100,000 women die of preeclampsia every year. It occurs in 3-14% (varies significantly depending on racial origin or ethnicity and geographical region) of pregnant women, in 75% of cases - in a mild form, and in 25% - in a severe form. During severe pre-eclampsia-eclampsia, perinatal mortality increases by 5 times and stillbirth by 9.6 times. Considering that the only way to treat the disease is to end the pregnancy, the main thing is timely diagnosis and prevention of the disease. Identification of high-risk pregnant women for PE and giving prophylaxis would reduce the incidence of preterm PE. First-trimester screening model developed by the Fetal Medicine Foundation (FMF), which uses the Bayes-theorem to combine maternal characteristics and medical history together with measurements of mean arterial pressure, uterine artery pulsatility index, and serum placental growth factor, has been proven to be effective and have superior screening performance to that of traditional risk factor-based approach for the prediction of PE (2) Methods: Retrospective single center screening study. The study population consisted of women from the Tbilisi maternity hospital “Pineo medical ecosystem” who met the following criteria: they spoke Georgian, English, or Russian and agreed to participate in the study after discussing informed consent and answering questions. Prior to the study, the informed consent forms approved by the Institutional Review Board were obtained from the study subjects. Early assessment of preeclampsia was performed between 11-13 weeks of pregnancy. The following were evaluated: anamnesis, dopplerography of the uterine artery, mean arterial blood pressure, and biochemical parameter: Pregnancy-associated plasma protein A (PAPP-A). Individual risk assessment was performed with performed by Fast Screen 3.0 software ThermoFisher scientific. Results: A total of 513 women were recruited and through the study, 51 women were diagnosed with preeclampsia (34.5% in the pregnant women with high risk, 6.5% in the pregnant women with low risk; P<0.000 1). Conclusions: First-trimester screening combining maternal factors with uterine artery Doppler, blood pressure, and pregnancy-associated plasma protein-A is useful to predict PE in a routine care setting. More patient studies are needed for final conclusions. The research is still ongoing.

Keywords: first-trimester, preeclampsia, screening, pregnancy-associated plasma protein

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234 Study of Polish and Ukrainian Volunteers Helping War Refugees. Psychological and Motivational Conditions of Coping with Stress of Volunteer Activity

Authors: Agata Chudzicka-Czupała, Nadiya Hapon, Liudmyla Karamushka, Marta żywiołek-Szeja

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Objectives: The study is about the determinants of coping with stress connected with volunteer activity for Russo-Ukrainian war 2022 refugees. We examined the mental health reactions, chosen psychological traits, and motivational functions of volunteers working in Poland and Ukraine in relation to their coping with stress styles. The study was financed with funds from the Foundation for Polish Science in the framework of the FOR UKRAINE Programme. Material and Method: The study was conducted in 2022. The study was a quantitative, questionnaire-based survey. Data was collected through an online survey. The volunteers were asked to assess their propensity to use different styles of coping with stress connected with their activity for Russo-Ukrainian war refugees using The Brief Coping Orientation to Problems Experienced Inventory (Brief-COPE) questionnaire. Depression, anxiety, and stress were measured using the Depression, Anxiety, and Stress (DASS)-21 item scale. Chosen psychological traits, psychological capital and hardiness, were assessed by The Psychological Capital Questionnaire and The Norwegian Revised Scale of Hardiness (DRS-15R). Then The Volunteer Function Inventory (VFI) was used. The significance of differences between the variable means of the samples was tested by the Student's t-test. We used multivariate linear regression to identify factors associated with coping with stress styles separately for each national sample. Results: The sample consisted of 720 volunteers helping war refugees (in Poland, 435 people, and 285 in Ukraine). The results of the regression analysis indicate variables that are significant predictors of the propensity to use particular styles of coping with stress (problem-focused style, emotion-focused style and avoidant coping). These include levels of depression and stress, individual psychological characteristics and motivational functions, different for Polish and Ukrainians. Ukrainian volunteers are significantly more likely to use all three coping with stress styles than Polish ones. The results also prove significant differences in the severity of anxiety, stress and depression, the selected psychological traits and motivational functions studied, which led volunteers to participate in activities for war refugees. Conclusions: The results show that depression and stress severity, as well as psychological capital and hardiness, and motivational factors are connected with coping with stress behavior. The results indicate the need for increased attention to the well-being of volunteers acting under stressful conditions. They also prove the necessity of guiding the selection of people for specific types of volu

Keywords: anxiety, coping with stress styles, depression, hardiness, mental health, motivational functions, psychological capital, resilience, stress, war, volunteer, civil society

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233 Open Theism in Confinement: A Conversation between Open and Confined Views of God

Authors: Charles Atkins

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Anakainosis-desmios is the experience of spiritual renewal during incarceration. "Anakainosis” is a Greek word for “renovation or renewal" that has taken on profound meaning in Christocentric theology where it is defined as the phenomenon of spiritual renewal or a change of heart that is achieved by God’s power. “Desmios” is another Greek word found in the Bible which stands for “one who is bound or a prisoner. Anakainosis-desmios occurs when a person, while residing in an environment of surveillance and coercion, has his consciousness renewed in such a way that he generates unexpected emancipatory and hospitable attitudes. They expressed an awareness of the prison environment and a willingness to engage that environment through their transformed relationships with time, space, matter, and people. By the end of the 20th century, Open Theism, gained the attention of many American evangelicals and theologians. Open Theism was born out of the concerns people had about those scriptures which demonstrate a dynamic God who has unparalled wisdom instead of omniscience; liberating power instead of omnipotence; and abiding faithfulness instead of immutability—all of these attributes being aspects of God’s love for humanity. Scriptural exegesis is one of the primary factors that informed the creation of the open view of God and many who hold this view claim that the divine attributes of omniscience, omnipotence and immutability are not necessarily Scriptural but rather philosophical attempts to define the nature of God. Scriptures that do not support such divine attributes have been a source of distress for many. Some would say that open theists have created lenses that enable a Bible student to gain comfort from those scriptures which seem to show God demonstrating repentance, disappointment and a readiness to learn. This paper will bring Open Theism into conversation with anakainosis-desmios. For open theists the reading of Scripture is an important part of the foundation of their perspectives. Open theists focus on certain Scriptures which demonstrate God showing repentance, disappointment and a readiness to learn. This focus led to their questioning of the systematic theologies that have been created and the biblical hermeneutics that have been used historically as lenses for interpreting such Scriptures. The perspective of anakainosis-desmios is also significantly influenced by the reading of Scripture. Spiritual renewal while incarcerated can occur largely through the religious practice of Bible study. Studying Scriptures during incarceration has supported many people who are seeking to develop new renderings of reality that empower them to flourish in some way despite the hostile environment of prisons. A conversation between the two points of view on the God of the Bible will lead to an expansion of both and to a deepening of a person's experience of Scripture Study.

Keywords: open theism, anakainosis-desmios, religion in prison, open theology, practical theology, Bible, scripture, openness of God, incarceration, prison

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232 A Delphi Study to Build Consensus for Tuberculosis Control Guideline to Achieve Who End Tb 2035 Strategy

Authors: Pui Hong Chung, Cyrus Leung, Jun Li, Kin On Kwok, Ek Yeoh

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Introduction: Studies for TB control in intermediate tuberculosis burden countries (IBCs) comprise a relatively small proportion in TB control literature, as compared to the effort put in high and low burden counterparts. It currently lacks of consensus in the optimal weapons and strategies we can use to combat TB in IBCs; guidelines of TB control are inadequate and thus posing a great obstacle in eliminating TB in these countries. To fill-in the research and services gap, we need to summarize the findings of the effort in this regard and to seek consensus in terms of policy making for TB control, we have devised a series of scoping and Delphi studies for these purposes. Method: The scoping and Delphi studies are conducted in parallel to feed information for each other. Before the Delphi iterations, we have invited three local experts in TB control in Hong Kong to participate in the pre-assessment round of the Delphi study to comments on the validity, relevance, and clarity of the Delphi questionnaire. Result: Two scoping studies, regarding LTBI control in health care workers in IBCs and TB control in elderly of IBCs respectively, have been conducted. The result of these two studies is used as the foundation for developing the Delphi questionnaire, which tapped on seven areas of question, namely: characteristics of IBCs, adequacy of research and services in LTBI control in IBCs, importance and feasibility of interventions for TB control and prevention in hospital, screening and treatment of LTBI in community, reasons of refusal to/ default from LTBI treatment, medical adherence of LTBI treatment, and importance and feasibility of interventions for TB control and prevention in elderly in IBCs. The local experts also commented on the two scoping studies conducted, thus act as the sixth phase of expert consultation in Arksey and O’Malley framework of scoping studies, to either nourish the scope and strategies used in these studies or to supplement ideas for further scoping or systematic review studies. In the subsequent stage, an international expert panel, comprised of 15 to 20 experts from IBCs in Western Pacific Region, will be recruited to join the two-round anonymous Delphi iterations. Four categories of TB control experts, namely clinicians, policy makers, microbiologists/ laboratory personnel, and public health clinicians will be our target groups. A consensus level of 80% is used to determine the achievement of consensus on particular issues. Key messages: 1. Scoping review and Delphi method are useful to identify gaps and then achieve consensus in research. 2. Lots of resources are put in the high burden countries now. However, the usually neglected intermediate-burden countries with TB is an indispensable part for achieving the ambitious WHO End TB 2035 target.

Keywords: dephi questionnaire, tuberculosis, WHO, latent TB infection

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231 Investigation of Processing Conditions on Rheological Features of Emulsion Gels and Oleogels Stabilized by Biopolymers

Authors: M. Sarraf, J. E. Moros, M. C. Sánchez

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Oleogels are self-standing systems that are able to trap edible liquid oil into a tridimensional network and also help to use less fat by forming crystallization oleogelators. There are different ways to generate oleogelation and oil structuring, including direct dispersion, structured biphasic systems, oil sorption, and indirect method (emulsion-template). The selection of processing conditions as well as the composition of the oleogels is essential to obtain a stable oleogel with characteristics suitable for its purpose. In this sense, one of the ingredients widely used in food products to produce oleogels and emulsions is polysaccharides. Basil seed gum (BSG), with the scientific name Ocimum basilicum, is a new native polysaccharide with high viscosity and pseudoplastic behavior because of its high molecular weight in the food industry. Also, proteins can stabilize oil in water due to the presence of amino and carboxyl moieties that result in surface activity. Whey proteins are widely used in the food industry due to available, cheap ingredients, nutritional and functional characteristics such as emulsifier and a gelling agent, thickening, and water-binding capacity. In general, the interaction of protein and polysaccharides has a significant effect on the food structures and their stability, like the texture of dairy products, by controlling the interactions in macromolecular systems. Using edible oleogels as oil structuring helps for targeted delivery of a component trapped in a structural network. Therefore, the development of efficient oleogel is essential in the food industry. A complete understanding of the important points, such as the ratio oil phase, processing conditions, and concentrations of biopolymers that affect the formation and stability of the emulsion, can result in crucial information in the production of a suitable oleogel. In this research, the effects of oil concentration and pressure used in the manufacture of the emulsion prior to obtaining the oleogel have been evaluated through the analysis of droplet size and rheological properties of obtained emulsions and oleogels. The results show that the emulsion prepared in the high-pressure homogenizer (HPH) at higher pressure values has smaller droplet sizes and a higher uniformity in the size distribution curve. On the other hand, in relation to the rheological characteristics of the emulsions and oleogels obtained, the predominantly elastic character of the systems must be noted, as they present values of the storage modulus higher than those of losses, also showing an important plateau zone, typical of structured systems. In the same way, if steady-state viscous flow tests have been analyzed on both emulsions and oleogels, the result is that, once again, the pressure used in the homogenizer is an important factor for obtaining emulsions with adequate droplet size and the subsequent oleogel. Thus, various routes for trapping oil inside a biopolymer matrix with adjustable mechanical properties could be applied for the creation of the three-dimensional network in order to the oil absorption and creating oleogel.

Keywords: basil seed gum, particle size, viscoelastic properties, whey protein

Procedia PDF Downloads 44
230 Sensor Network Structural Integration for Shape Reconstruction of Morphing Trailing Edge

Authors: M. Ciminello, I. Dimino, S. Ameduri, A. Concilio

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Improving aircraft's efficiency is one of the key elements of Aeronautics. Modern aircraft possess many advanced functions, such as good transportation capability, high Mach number, high flight altitude, and increasing rate of climb. However, no aircraft has a possibility to reach all of this optimized performance in a single airframe configuration. The aircraft aerodynamic efficiency varies considerably depending on the specific mission and on environmental conditions within which the aircraft must operate. Structures that morph their shape in response to their surroundings may at first seem like the stuff of science fiction, but take a look at nature and lots of examples of plants and animals that adapt to their environment would arise. In order to ensure both the controllable and the static robustness of such complex structural systems, a monitoring network is aimed at verifying the effectiveness of the given control commands together with the elastic response. In order to achieve this kind of information, the use of FBG sensors network is, in this project, proposed. The sensor network is able to measure morphing structures shape which may show large, global displacements due to non-standard architectures and materials adopted. Chord -wise variations may allow setting and chasing the best layout as a function of the particular and transforming reference state, always targeting best aerodynamic performance. The reason why an optical sensor solution has been selected is that while keeping a few of the contraindication of the classical systems (like cabling, continuous deployment, and so on), fibre optic sensors may lead to a dramatic reduction of the wires mass and weight thanks to an extreme multiplexing capability. Furthermore, the use of the ‘light’ as ‘information carrier’, permits dealing with nimbler, non-shielded wires, and avoids any kind of interference with the on-board instrumentation. The FBG-based transducers, herein presented, aim at monitoring the actual shape of adaptive trailing edge. Compared to conventional systems, these transducers allow more fail-safe measurements, by taking advantage of a supporting structure, hosting FBG, whose properties may be tailored depending on the architectural requirements and structural constraints, acting as strain modulator. The direct strain may, in fact, be difficult because of the large deformations occurring in morphing elements. A modulation transducer is then necessary to keep the measured strain inside the allowed range. In this application, chord-wise transducer device is a cantilevered beam sliding trough the spars and copying the camber line of the ATE ribs. FBG sensors array position are dimensioned and integrated along the path. A theoretical model describing the system behavior is implemented. To validate the design, experiments are then carried out with the purpose of estimating the functions between rib rotation and measured strain.

Keywords: fiber optic sensor, morphing structures, strain sensor, shape reconstruction

Procedia PDF Downloads 301
229 Criticism and Theorizing of Architecture and Urbanism in the Creativity Cinematographic Film

Authors: Wafeek Mohamed Ibrahim Mohamed

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In the era of globalization, the camera of the cinematographic film plays a very important role in terms of monitoring and documenting what it was and distinguished the built environment of architectural and Urbanism. Moving the audience to the out-going backward through the cinematographic film and its stereophonic screen by which the picture appears at its best and its coexistence reached now its third dimension. The camera has indicated to the city shape with its paths, (alley) lanes, buildings and its architectural style. We have seen the architectural styles in its cinematic scenes which remained a remembrance in its history, in spite of the fact that some of which has been disappearing as what happened to ‘Boulak Bridge’ in Cairo built by ‘Eiffel’ and it has been demolished, but it remains a remembrance we can see it in the films of ’Usta Hassan’and A Crime in the Quiet Neighborhood. The purpose of the fundamental research is an attempt to reach a critical view of the idea of criticism and theorizing for Architecture and Urbanism in the cinematographic film and their relationship and reflection on the ‘audience’ understanding of the public opinion related to our built environment of Architectural and Urbanism with its problems and hardness. It is like as a trial to study the Architecture and Urbanism of the built environment in the cinematographic film and hooking up (linking) a realistic view of the governing conceptual significance thereof. The aesthetic thought of our traditional environment, in a psychological and anthropological framework, derives from the cinematic concept of the Architecture and Urbanism of the place and the dynamics of the space. The architectural space considers the foundation stone of the cinematic story and the main background of the events therein, which integrate the audience into a romantic trip to the city through its symbolized image of the spaces, lanes [alley], etc. This will be done through two main branches: firstly, Reviewing during time pursuit of the Architecture and Urbanism in the cinematographic films the thirties ago in the Egyptian cinema [onset from the film ‘Bab El Hadid’ to the American University at a film of ‘Saidi at the American University’]. The research concludes the importance of the need to study the cinematic films which deal with our societies, their architectural and Urbanism concerns whether the traditional ones or the contemporary and their crisis (such as the housing crisis in the film of ‘Krakoun in the street’, etc) to study the built environment with its architectural dynamic spaces through a modernist view. In addition, using the cinema as an important Media for spreading the ideas, documenting and monitoring the current changes in the built environment through its various dramas and comedies, etc. The cinema is considered as a mirror of the society and its built environment over the epochs. It assured the unique case constituted by cinema with the audience (public opinion) through a sense of emptiness and forming the mental image related to the city and the built environment.

Keywords: architectural and urbanism, cinematographic architectural, film, space in the film, media

Procedia PDF Downloads 213
228 Mechanical and Durability Characteristics of Roller Compacted Geopolymer Concrete Using Recycled Concrete Aggregate

Authors: Syfur Rahman, Mohammad J. Khattak

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Every year a huge quantity of recycling concrete aggregate (RCA) is generated in the United States of America. Utilization of RCA can solve the storage problem, prevent environmental pollution, and reduce the construction cost. However, due to the overall low strength and durability characteristics of RCA, its usages are limited to a certain area like a landfill, low strength base material, replacement of a few percentages of virgin aggregates in Portland cement concrete, etc. This study focuses on the improvement of the strength and durability characteristics of RCA by introducing the concept of roller-compacted geopolymer concrete. In this research, developed roller-compacted geopolymer concrete (RCGPC) and roller-compacted cement concrete (RCC) mixtures containing 100% recycled concrete aggregate were evaluated and compared. Several selected RCGPC mixtures were investigated to find out the effect of mixture variables, including sodium hydroxide (NaOH) molar concentration, sodium silicate (Na₂SiO₃), to sodium hydroxide (NaOH) ratio on the strength, stiffness and durability characteristics of the developed RCGPC. Sodium hydroxide (NaOH) and sodium silicate (Na₂SiO₃) were mixed in different ratios to synthesize the alkali activator. American Concrete Pavement Association (ACPA) recommended RCC gradation was used with a maximum nominal aggregate size of 19 mm with a 4% fine particle passing 0.075 mm sieve. The mixtures were made using NaOH molar concentration of 8M and 10M along with, Na₂SiO₃ to NaOH ratio of 0 and 1 by mass and 15% class F fly ash. Optimum alkali content and moisture content were determined for each RCGPC and RCC mixtures, respectively, using modified proctor test. Compressive strength, semi-circular bending beam strength, and dynamic modulus test were conducted to evaluate the mechanistic characteristics of both mixtures. To determine the optimum curing conditions for RCGPC, effects of different curing temperature and curing duration on compressive strength were also studied. Sulphate attack and freeze-thaw tests were also carried out to assess the durability properties of the developed mixtures. X-ray diffraction (XRD) was used for morphology and microstructure analysis. From the optimum moisture content results, it was found that RCGPC has high alkali content, which was mainly due to the high absorption capacity of RCA. It was found that the mixtures with Na₂SiO₃ to NaOH ratio of 1 yielded about 60% higher compressive strength than the ratio of 0. Further, the mixtures using 10M NaOH concentrations and alkali ratio of 1 produced about 28 MPa of compressive strength, which was around 33% higher than 8M NaOH mixtures. Similar results were obtained for elastic and dynamic modulus of the mixtures. On the other hand, the semi-circular bending beam strength remained the same for both 8 and 10 molar NaOH geopolymer mixtures. Formation of new geopolymeric compounds and chemical bonds in the newly formed novel RCGPC mixtures were also discovered using XRD analysis. The results of mechanical and durability testing further revealed that RCGPC performed similarly to that of RCC mixtures. Based on the results of mechanical and durability testing, the developed RCGPC mixtures using 100% recycled concrete could be used as a cost-effective solution for the construction of pavement structures.

Keywords: roller compacted concrete, geopolymer concrete, recycled concrete aggregate, concrete pavement, fly ash

Procedia PDF Downloads 114
227 Creating Standards to Define the Role of Employment Specialists: A Case Study

Authors: Joseph Ippolito, David Megenhardt

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In the United States, displaced workers, the unemployed and those seeking to build additional work skills are provided employment training and job placement services through a system of One-Stop Career Centers that are sponsored by the country’s 593 local Workforce Boards. During the period 2010-2015, these centers served roughly 8 million individuals each year. The quality of services provided at these centers rests upon professional employment specialists who work closely with clients to identify their job interests, to connect them to appropriate training opportunities, to match them with needed supportive social services and to guide them to eventual employment. Despite the crucial role these Employment Specialists play, currently there are no broadly accepted standards that establish what these individuals are expected to do in the workplace, nor are there indicators to assess how well an individual performs these responsibilities. Education Development Center (EDC) and the United Labor Agency (ULA) have partnered to create a foundation upon which curriculum can be developed that addresses the skills, knowledge and behaviors that Employment Specialists must master in order to serve their clients effectively. EDC is a non-profit, education research and development organization that designs, implements, and evaluates programs to improve education, health and economic opportunity worldwide. ULA is the social action arm of organized labor in Greater Cleveland, Ohio. ULA currently operates One-Stop Career Centers in both Cleveland and Pittsburgh, Pennsylvania. This case study outlines efforts taken to create standards that define the work of Employment Specialists and to establish indicators that can guide assessment of work performance. The methodology involved in the study has engaged a panel of expert Employment Specialists in rigorous, structured dialogues that analyze and identify the characteristics that enable them to be effective in their jobs. It has also drawn upon and integrated reviews of the panel’s work by more than 100 other Employment Specialists across the country. The results of this process are two documents that provide resources for developing training curriculum for future Employment Specialists, namely: an occupational profile of an Employment Specialist that offers a detailed articulation of the skills, knowledge and behaviors that enable individuals to be successful at this job, and; a collection of performance based indicators, aligned to the profile, which illustrate what the work responsibilities of an Employment Specialist 'look like' a four levels of effectiveness ranging from novice to expert. The method of occupational analysis used by the study has application across a broad number of fields.

Keywords: assessment, employability, job standards, workforce development

Procedia PDF Downloads 210
226 Study of Biomechanical Model for Smart Sensor Based Prosthetic Socket Design System

Authors: Wei Xu, Abdo S. Haidar, Jianxin Gao

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Prosthetic socket is a component that connects the residual limb of an amputee with an artificial prosthesis. It is widely recognized as the most critical component that determines the comfort of a patient when wearing the prosthesis in his/her daily activities. Through the socket, the body weight and its associated dynamic load are distributed and transmitted to the prosthesis during walking, running or climbing. In order to achieve a good-fit socket for an individual amputee, it is essential to obtain the biomechanical properties of the residual limb. In current clinical practices, this is achieved by a touch-and-feel approach which is highly subjective. Although there have been significant advancements in prosthetic technologies such as microprocessor controlled knee and ankle joints in the last decade, the progress in designing a comfortable socket has been rather limited. This means that the current process of socket design is still very time-consuming, and highly dependent on the expertise of the prosthetist. Supported by the state-of-the-art sensor technologies and numerical simulations, a new socket design system is being developed to help prosthetists achieve rapid design of comfortable sockets for above knee amputees. This paper reports the research work related to establishing biomechanical models for socket design. Through numerical simulation using finite element method, comprehensive relationships between pressure on residual limb and socket geometry were established. This allowed local topological adjustment for the socket so as to optimize the pressure distributions across the residual limb. When the full body weight of a patient is exerted on the residual limb, high pressures and shear forces between the residual limb and the socket occur. During numerical simulations, various hyperplastic models, namely Ogden, Yeoh and Mooney-Rivlin, were used, and their effectiveness in representing the biomechanical properties of soft tissues of the residual limb was evaluated. This also involved reverse engineering, which resulted in an optimal representative model under compression test. To validate the simulation results, a range of silicone models were fabricated. They were tested by an indentation device which yielded the force-displacement relationships. Comparisons of results obtained from FEA simulations and experimental tests showed that the Ogden model did not fit well the soft tissue material indentation data, while the Yeoh model gave the best representation of the soft tissue mechanical behavior under indentation. Compared with hyperplastic model, the result showed that elastic model also had significant errors. In addition, normal and shear stress distributions on the surface of the soft tissue model were obtained. The effect of friction in compression testing and the influence of soft tissue stiffness and testing boundary conditions were also analyzed. All these have contributed to the overall goal of designing a good-fit socket for individual above knee amputees.

Keywords: above knee amputee, finite element simulation, hyperplastic model, prosthetic socket

Procedia PDF Downloads 178
225 Open Joint Surgery for Temporomandibular Joint Internal Derangement: Wilkes Stages III-V

Authors: T. N. Goh, M. Hashmi, O. Hussain

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Temporomandibular joint (TMJ) dysfunction (TMD) is a condition that may affect patients via restricted mouth opening, significant pain during normal functioning, and/or reproducible joint noise. TMD includes myofascial pain, TMJ functional derangements (internal derangement, dislocation), and TMJ degenerative/inflammatory joint disease. Internal derangement (ID) is the most common cause of TMD-related clicking and locking. These patients are managed in a stepwise approach, from patient education (homecare advice and analgesia), splint therapy, physiotherapy, botulinum toxin treatment, to arthrocentesis. Arthrotomy is offered when the aforementioned treatment options fail to alleviate symptoms and improve quality of life. The aim of this prospective study was to review the outcomes of jaw joint open surgery in TMD patients. Patients who presented from 2015-2022 at the Oral and Maxillofacial Surgery Department in the Doncaster NHS Foundation Trust, UK, with a Wilkes classification of III -V were included. These patients underwent either i) discopexy with bone-anchoring suture (9); ii) intrapositional temporalis flap (ITF) with bone-anchoring suture (3); iii) eminoplasty and discopexy with suturing to the capsule (3); iii) discectomy + ITF with bone-anchoring suture (1); iv) discoplasty + bone-anchoring suture (1); v) ITF (1). Maximum incisal opening (MIO) was assessed pre-operatively and at each follow-up. Pain score, determined via the visual analogue scale (VAS, with 0 being no pain and 10 being the worst pain), was also recorded. A total of 18 eligible patients were identified with a mean age of 45 (range 22 - 79), of which 16 were female. The patients were scored by Wilkes Classification as III (14), IV (1), or V (4). Twelve patients had anterior disc displacement without reduction (66%) and six had degenerative/arthritic changes (33%) to the TMJ. The open joint procedure resulted in an increase in MIO and reduction in pain VAS and for the majority of patients, across all Wilkes Classifications. Pre-procedural MIO was 22.9 ± 7.4 mm and VAS was 7.8 ± 1.5. At three months post-procedure there was an increase in MIO to 34.4 ± 10.4 mm (p < 0.01) and a decrease in the VAS to 1.5 ± 2.9 (p < 0.01). Three patients were lost to follow-up prior to six months. Six were discharged at six month review and five patients were discharged at 12 months review as they were asymptomatic with good mouth opening. Four patients are still attending for annual botulinum toxin treatment. Two patients (Wilkes III and V) subsequently underwent TMJ replacement (11%). One of these patients (Wilkes III) had improvement initially to MIO of 40 mm, but subsequently relapsed to less than 20 mm due to lack of compliance with jaw rehabilitation device post-operatively. Clinical improvements in 89% of patients within the study group were found, with a return to near normal MIO range and reduced pain score. Intraoperatively, the operator found bone-anchoring suture used for discopexy/discoplasty more secure than the soft tissue anchoring suturing technique.

Keywords: bone anchoring suture, open temporomandibular joint surgery, temporomandibular joint, temporomandibular joint dysfunction

Procedia PDF Downloads 79
224 Economic Impact of Rana Plaza Collapse

Authors: Md. Omar Bin Harun Khan

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The collapse of the infamous Rana Plaza, a multi-storeyed commercial building in Savar, near Dhaka, Bangladesh has brought with it a plethora of positive and negative consequences. Bangladesh being a key player in the export of clothing, found itself amidst a wave of economic upheaval following this tragic incident that resulted in numerous Bangladeshis, most of whom were factory workers. This paper compares the consequences that the country’s Ready Made Garments (RMG) sector is facing now, two years into the incident. The paper presents a comparison of statistical data from study reports and brings forward perspectives from all dimensions of Labour, Employment and Industrial Relations in Bangladesh following the event. The paper brings across the viewpoint of donor organizations and donor countries, the impacts of several initiatives taken by foreign organizations like the International Labour Organization, and local entities like the Bangladesh Garment Manufacturers and Exporters Association (BGMEA) in order to reinforce compliance and stabilize the shaky foundation that the RMG sector had found itself following the collapse. Focus of the paper remains on the stance taken by the suppliers in Bangladesh, with inputs from buying houses and factories, and also on the reaction of foreign brands. The paper also focuses on the horrific physical, mental and financial implications sustained by the victims and their families, and the consequent uproar from workers in general regarding compliance with work safety and workers’ welfare conditions. The purpose is to get across both sides of the scenario: the economic impact that suppliers / factories/ sellers/ buying houses/exporters have faced in Bangladesh as a result of complete loss of reliability on them regarding working standards; and also to cover the aftershock felt on the other end of the spectrum by the importers/ buyers, particularly the foreign entities, in terms of the sudden accountability of being affiliated with non- compliant factories. The collapse of Rana Plaza has received vast international attention and strong criticism. Nevertheless, the almost immediate strengthening of labourrights and the wholesale reform undertaken on all sides of the supply chain, evidence a move of all local and foreign stakeholders towards greater compliance and taking of precautionary steps for prevention of further disasters. The tragedy that Rana Plaza embodies served as a much-needed epiphany for the soaring RMG Sector of Bangladesh. Prompt co-operation on the part of all stakeholders and regulatory bodies now show a move towards sustainable development, which further ensures safeguarding against any future irregularities and pave the way for steady economic growth.

Keywords: economy, employment standards, Rana Plaza, RMG

Procedia PDF Downloads 305
223 Drug Delivery Cationic Nano-Containers Based on Pseudo-Proteins

Authors: Sophio Kobauri, Temur Kantaria, Nina Kulikova, David Tugushi, Ramaz Katsarava

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The elaboration of effective drug delivery vehicles is still topical nowadays since targeted drug delivery is one of the most important challenges of the modern nanomedicine. The last decade has witnessed enormous research focused on synthetic cationic polymers (CPs) due to their flexible properties, in particular as non-viral gene delivery systems, facile synthesis, robustness, not oncogenic and proven gene delivery efficiency. However, the toxicity is still an obstacle to the application in pharmacotherapy. For overcoming the problem, creation of new cationic compounds including the polymeric nano-size particles – nano-containers (NCs) loading with different pharmaceuticals and biologicals is still relevant. In this regard, a variety of NCs-based drug delivery systems have been developed. We have found that amino acid-based biodegradable polymers called as pseudo-proteins (PPs), which can be cleared from the body after the fulfillment of their function are highly suitable for designing pharmaceutical NCs. Among them, one of the most promising are NCs made of biodegradable Cationic PPs (CPPs). For preparing new cationic NCs (CNCs), we used CPPs composed of positively charged amino acid L-arginine (R). The CNCs were fabricated by two approaches using: (1) R-based homo-CPPs; (2) Blends of R-based CPPs with regular (neutral) PPs. According to the first approach NCs we prepared from CPPs 8R3 (composed of R, sebacic acid and 1,3-propanediol) and 8R6 (composed of R, sebacic acid and 1,6-hexanediol). The NCs prepared from these CPPs were 72-101 nm in size with zeta potential within +30 ÷ +35 mV at a concentration 6 mg/mL. According to the second approach, CPPs 8R6 was blended in organic phase with neutral PPs 8L6 (composed of leucine, sebacic acid and 1,6-hexanediol). The NCs prepared from the blends were 130-140 nm in size with zeta potential within +20 ÷ +28 mV depending on 8R6/8L6 ratio. The stability studies of fabricated NCs showed that no substantial change of the particle size and distribution and no big particles’ formation is observed after three months storage. In vitro biocompatibility study of the obtained NPs with four different stable cell lines: A549 (human), U-937 (human), RAW264.7 (murine), Hepa 1-6 (murine) showed both type cathionic NCs are biocompatible. The obtained data allow concluding that the obtained CNCs are promising for the application as biodegradable drug delivery vehicles. This work was supported by the joint grant from the Science and Technology Center in Ukraine and Shota Rustaveli National Science Foundation of Georgia #6298 'New biodegradable cationic polymers composed of arginine and spermine-versatile biomaterials for various biomedical applications'.

Keywords: biodegradable polymers, cationic pseudo-proteins, nano-containers, drug delivery vehicles

Procedia PDF Downloads 130
222 Motivation of Doctors and its Impact on the Quality of Working Life

Authors: E. V. Fakhrutdinova, K. R. Maksimova, P. B. Chursin

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At the present stage of the society progress the health care is an integral part of both the economic system and social, while in the second case the medicine is a major component of a number of basic and necessary social programs. Since the foundation of the health system are highly qualified health professionals, it is logical proposition that increase of doctor`s professionalism improves the effectiveness of the system as a whole. Professionalism of the doctor is a collection of many components, essential role played by such personal-psychological factors as honesty, willingness and desire to help people, and motivation. A number of researchers consider motivation as an expression of basic human needs that have passed through the “filter” which is a worldview and values learned in the process of socialization by the individual, to commit certain actions designed to achieve the expected result. From this point of view a number of researchers propose the following classification of highly skilled employee’s needs: 1. the need for confirmation the competence (setting goals that meet the professionalism and receipt of positive emotions in their decision), 2. The need for independence (the ability to make their own choices in contentious situations arising in the process carry out specialist functions), 3. The need for ownership (in the case of health care workers, to the profession and accordingly, high in the eyes of the public status of the doctor). Nevertheless, it is important to understand that in a market economy a significant motivator for physicians (both legal and natural persons) is to maximize its own profits. In the case of health professionals duality motivational structure creates an additional contrast, as in the public mind the image of the ideal physician; usually a altruistically minded person thinking is not primarily about their own benefit, and to assist others. In this context, the question of the real motivation of health workers deserves special attention. The survey conducted by the American researcher Harrison Terni for the magazine "Med Tech" in 2010 revealed the opinion of more than 200 medical students starting courses, and the primary motivation in a profession choice is "desire to help people", only 15% said that they want become a doctor, "to earn a lot". From the point of view of most of the classical theories of motivation this trend can be called positive, as intangible incentives are more effective. However, it is likely that over time the opinion of the respondents may change in the direction of mercantile motives. Thus, it is logical to assume that well-designed system of motivation of doctor`s labor should be based on motivational foundations laid during training in higher education.

Keywords: motivation, quality of working life, health system, personal-psychological factors, motivational structure

Procedia PDF Downloads 335
221 On the Question of Ideology: Criticism of the Enlightenment Approach and Theory of Ideology as Objective Force in Gramsci and Althusser

Authors: Edoardo Schinco

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Studying the Marxist intellectual tradition, it is possible to verify that there were numerous cases of philosophical regression, in which the important achievements of detailed studies have been replaced by naïve ideas and previous misunderstandings: one of most important example of this tendency is related to the question of ideology. According to a common Enlightenment approach, the ideology is essentially not a reality, i.e., a factor capable of having an effect on the reality itself; in other words, the ideology is a mere error without specific historical meaning, which is only due to ignorance or inability of subjects to understand the truth. From this point of view, the consequent and immediate practice against every form of ideology are the rational dialogue, the reasoning based on common sense, in order to dispel the obscurity of ignorance through the light of pure reason. The limits of this philosophical orientation are however both theoretical and practical: on the one hand, the Enlightenment criticism of ideology is not an historicistic thought, since it cannot grasp the inner connection that ties an historical context and its peculiar ideology together; moreover, on the other hand, when the Enlightenment approach fails to release people from their illusions (e.g., when the ideology persists, despite the explanation of its illusoriness), it usually becomes a racist or elitarian thought. Unlike this first conception of ideology, Gramsci attempts to recover Marx’s original thought and to valorize its dialectical methodology with respect to the reality of ideology. As Marx suggests, the ideology – in negative meaning – is surely an error, a misleading knowledge, which aims to defense the current state of things and to conceal social, political or moral contradictions; but, that is precisely why the ideological error is not casual: every ideology mediately roots in a particular material context, from which it takes its reason being. Gramsci avoids, however, any mechanistic interpretation of Marx and, for this reason; he underlines the dialectic relation that exists between material base and ideological superstructure; in this way, a specific ideology is not only a passive product of base but also an active factor that reacts on the base itself and modifies it. Therefore, there is a considerable revaluation of ideology’s role in maintenance of status quo and the consequent thematization of both ideology as objective force, active in history, and ideology as cultural hegemony of ruling class on subordinate groups. Among the Marxists, the French philosopher Louis Althusser also gives his contribution to this crucial question; as follower of Gramsci’s thought, he develops the idea of ideology as an objective force through the notions of Repressive State Apparatus (RSA) and Ideological State Apparatuses (ISA). In addition to this, his philosophy is characterized by the presence of structuralist elements, which must be studied, since they deeply change the theoretical foundation of his Marxist thought.

Keywords: Althusser, enlightenment, Gramsci, ideology

Procedia PDF Downloads 170
220 Regional Analysis of Freight Movement by Vehicle Classification

Authors: Katerina Koliou, Scott Parr, Evangelos Kaisar

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The surface transportation of freight is particularly vulnerable to storm and hurricane disasters, while at the same time, it is the primary transportation mode for delivering medical supplies, fuel, water, and other essential goods. To better plan for commercial vehicles during an evacuation, it is necessary to understand how these vehicles travel during an evacuation and determine if this travel is different from the general public. The research investigation used Florida's statewide continuous-count station traffic volumes, where then compared between years, to identify locations where traffic was moving differently during the evacuation. The data was then used to identify days on which traffic was significantly different between years. While the literature on auto-based evacuations is extensive, the consideration of freight travel is lacking. To better plan for commercial vehicles during an evacuation, it is necessary to understand how these vehicles travel during an evacuation and determine if this travel is different from the general public. The goal of this research was to investigate the movement of vehicles by classification, with an emphasis on freight during two major evacuation events: hurricanes Irma (2017) and Michael (2018). The methodology of the research was divided into three phases: data collection and management, spatial analysis, and temporal comparisons. Data collection and management obtained continuous-co station data from the state of Florida for both 2017 and 2018 by vehicle classification. The data was then processed into a manageable format. The second phase used geographic information systems (GIS) to display where and when traffic varied across the state. The third and final phase was a quantitative investigation into which vehicle classifications were statistically different and on which dates statewide. This phase used a two-sample, two-tailed t-test to compare sensor volume by classification on similar days between years. Overall, increases in freight movement between years prevented a more precise paired analysis. This research sought to identify where and when different classes of vehicles were traveling leading up to hurricane landfall and post-storm reentry. Of the more significant findings, the research results showed that commercial-use vehicles may have underutilized rest areas during the evacuation, or perhaps these rest areas were closed. This may suggest that truckers are driving longer distances and possibly longer hours before hurricanes. Another significant finding of this research was that changes in traffic patterns for commercial-use vehicles occurred earlier and lasted longer than changes for personal-use vehicles. This finding suggests that commercial vehicles are perhaps evacuating in a fashion different from personal use vehicles. This paper may serve as the foundation for future research into commercial travel during evacuations and explore additional factors that may influence freight movements during evacuations.

Keywords: evacuation, freight, travel time, evacuation

Procedia PDF Downloads 41
219 Combained Cultivation of Endemic Strains of Lactic Acid Bacteria and Yeast with Antimicrobial Properties

Authors: A. M. Isakhanyan, F. N. Tkhruni, N. N. Yakimovich, Z. I. Kuvaeva, T. V. Khachatryan

Abstract:

Introduction: At present, the simbiotics based on different genera and species of lactic acid bacteria (LAB) and yeasts are used. One of the basic properties of probiotics is presence of antimicrobial activity and therefore selection of LAB and yeast strains for their co-cultivation with the aim of increasing of the activity is topical. Since probiotic yeast and bacteria have different mechanisms of action, natural synergies between species, higher viability and increasing of antimicrobial activity might be expected from mixing both types of probiotics. Endemic strains of LAB Enterococcus faecium БТK-64, Lactobaccilus plantarum БТK-66, Pediococcus pentosus БТK-28, Lactobacillus rhamnosus БТK-109 and Kluyveromyces lactis БТX-412, Saccharomycopsis sp. БТX- 151 strains of yeast, with probiotic properties and hight antimicrobial activity, were selected. Strains are deposited in "Microbial Depository Center" (MDC) SPC "Armbiotechnology". Methods: LAB and yeast strains were isolated from different dairy products from rural households of Armenia. The genotyping by 16S rRNA sequencing for LAB and 26S RNA sequencing for yeast were used. Combined cultivation of LAB and yeast strains was carried out in the nutrient media on the basis of milk whey, in anaerobic conditions (without shaker, in a thermostat at 37oC, 48 hours). The complex preparations were obtained by purification of cell free culture broth (CFC) broth by the combination of ion-exchange chromatography and gel filtration methods. The spot-on-lawn method was applied for determination of antimicrobial activity and expressed in arbitrary units (AU/ml). Results. The obtained data showed that at the combined growth of bacteria and yeasts, the cultivation conditions (medium composition, time of growth, genera of LAB and yeasts) affected the display of antimicrobial activity. Purification of CFC broth allowed obtaining partially purified antimicrobial complex preparation which contains metabiotics from both bacteria and yeast. The complex preparation inhibited the growth of pathogenic and conditionally pathogenic bacteria, isolated from various internal organs from diseased animals and poultry with greater efficiency than the preparations derived individually alone from yeast and LAB strains. Discussion. Thus, our data shown perspectives of creation of a new class of antimicrobial preparations on the basis of combined cultivation of endemic strains of LAB and yeast. Obtained results suggest the prospect of use of the partially purified complex preparations instead antibiotics in the agriculture and for food safety. Acknowledgments: This work was supported by the RA MES State Committee of Science and Belarus National Foundation for Basic Research in the frames of the joint Armenian - Belarusian joint research project 13РБ-064.

Keywords: co-cultivation, antimicrobial activity, biosafety, metabiotics, lactic acid bacteria, yeast

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218 Reframing Physical Activity for Health

Authors: M. Roberts

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We Are Undefeatable - is a mass marketing behaviour change campaign that aims to support the least active people living with long term health conditions to be more active. This is an important issue to address because people with long term conditions are an historically underserved community for the sport and physical activity sector and the least active of those with long term conditions have the most to gain in health and wellbeing benefits. The campaign has generated a significant change in the way physical activity is communicated and people with long term conditions are represented in the media and marketing. The goal is to create a social norm around being active. The campaign is led by a unique partnership of organisations: the Richmond Group of Charities (made up of Age UK, Alzheimer’s Society, Asthma + Lung UK, Breast Cancer Now, British Heart Foundation, British Red Cross, Diabetes UK, Macmillan Cancer Support, Rethink Mental Illness, Royal Voluntary Service, Stroke Association, Versus Arthritis) along with Mind, MS Society, Parkinson’s UK and Sport England, with National Lottery Funding. It is underpinned by the COM-B model of behaviour change. It draws on the lived experience of people with multiple long term conditions to shape the look and feel of the campaign and all the resources available. People with long term conditions are the campaign messengers, central to the ethos of the campaign by telling their individual stories of overcoming barriers to be active with their health conditions. The central messaging is about finding a way to be active that works for the individual. We Are Undefeatable is evaluated through a multi-modal approach, including regular qualitative focus groups and a quantitative evaluation tracker undertaken three times a year. The campaign has highlighted the significant barriers to physical activity for people with long term conditions. This has changed the way our partnership talks about physical activity but has also had an impact on the wider sport and physical activity sector, prompting an increasing departure from traditional messaging and marketing approaches for this audience of people with long term conditions. The campaign has reached millions of people since its launch in 2019, through multiple marketing and partnership channels including primetime TV advertising and promotion through health professionals and in health settings. Its diverse storytellers make it relatable to its target audience and the achievable activities highlighted and inclusive messaging inspire our audience to take action as a result of seeing the campaign. The We Are Undefeatable campaign is a blueprint for physical activity campaigns; it not only addresses individual behaviour change but plays a role in addressing systemic barriers to physical activity by sharing the lived experience insight to shape policy and professional practice.

Keywords: behaviour change, long term conditions, partnership, relatable

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217 Potential Cross-Protection Roles of Chitooligosaccharide in Alleviating Cd Toxicity in Edible Rape (Brassica rapa L.)

Authors: Haiying Zong, Yi Yuan, Pengcheng Li

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Cadmium (Cd), one of the toxic heavy metals, has high solubility and mobility in agricultural soils and is readily taken up by roots and transported to the vegetative and reproductive organs which can cause deleterious effects on crop yield and quality. Excess Cd in plants can interfere with many metabolic processes, such as photosynthesis, transpiration, respiration or nutrients homeostasis. Generally, the main methods to reduce Cd accumulation in plants are to decrease the concentration of Cd in the soil solution through reduction of Cd influx into the soil system, site selection, and management practices. However, these approaches can be very costly and consume a lot of energy Therefore, it is critical to develop effective approaches to reduce the Cd concentration in plants. It is proved that chitooligosaccharide (COS) can enhance the plant's tolerance to abiotic stress including drought stress, salinity stress, and toxic metal stress. However, so far little information is known about whether foliar application with COS modulates Cd-induced toxicity in plants. The metal detoxification processes of plants treated with COS also remain unclear. In this study, edible rape (Brassica rapa L.), one of the most widely consumed leafy vegetables, was selected as an experimental mode plant. The effect of foliar application with COS on reducing Cd accumulation in edible rape was investigated. Moreover, Cd subcellular distribution pattern in response to Cd stress in the rape plant sprayed with COS was further tested in order to explore the potential detoxification mechanisms in plants. The results demonstrated that spraying COS at different concentrations (25, 50,100 and 200 mg L-1) possess diverse functions including growth-promoting,chlorophyll contents-enhancing, malondialdehyde (MDA) level-decreasing in leaves, Cd2+ concentration-decreasingin shoots and roots of edible rape under Cd stress. In addition, it was found that COS can also dramatically improve superoxide dismutase (SOD) activity, catalase (CAT) activity and peroxidase (POX) activity of edible rape leaves. The relievingeffect of COS was related to theconcentration and COS with 50-100 mg L-1 displayed the best activity. Furtherly, theexperiments results exhibitedthat COS could decrease the proportion of Cd in the organelle fraction of leaves by 40.1% while enhance the proportion of Cd in the soluble fraction by 13.2% at the concentration of 50 mg L-1. The above results showed that COS may have thepotential to improve plant resistance to Cd via promoting antioxidant enzyme activities and altering Cd subcellular distribution. All the results described here open up a new way to study the protection role of COS in alleviating Cd tolerance and lay the foundation for future research about the detoxification mechanism at subcellular level.

Keywords: chitooligosaccharide, cadmium, edible rape (Brassica rapa L.), subcellular distribution

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216 Institutional and Economic Determinants of Foreign Direct Investment: Comparative Analysis of Three Clusters of Countries

Authors: Ismatilla Mardanov

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There are three types of countries, the first of which is willing to attract foreign direct investment (FDI) in enormous amounts and do whatever it takes to make this happen. Therefore, FDI pours into such countries. In the second cluster of countries, even if the country is suffering tremendously from the shortage of investments, the governments are hesitant to attract investments because they are at the hands of local oligarchs/cartels. Therefore, FDI inflows are moderate to low in such countries. The third type is countries whose companies prefer investing in the most efficient locations globally and are hesitant to invest in the homeland. Sorting countries into such clusters, the present study examines the essential institutions and economic factors that make these countries different. Past literature has discussed various determinants of FDI in all kinds of countries. However, it did not classify countries based on government motivation, institutional setup, and economic factors. A specific approach to each target country is vital for corporate foreign direct investment risk analysis and decisions. The research questions are 1. What specific institutional and economic factors paint the pictures of the three clusters; 2. What specific institutional and economic factors are determinants of FDI; 3. Which of the determinants are endogenous and exogenous variables? 4. How can institutions and economic and political variables impact corporate investment decisions Hypothesis 1: In the first type, country institutions and economic factors will be favorable for FDI. Hypothesis 2: In the second type, even if country economic factors favor FDI, institutions will not. Hypothesis 3: In the third type, even if country institutions favorFDI, economic factors will not favor domestic investments. Therefore, FDI outflows occur in large amounts. Methods: Data come from open sources of the World Bank, the Fraser Institute, the Heritage Foundation, and other reliable sources. The dependent variable is FDI inflows. The independent variables are institutions (economic and political freedom indices) and economic factors (natural, material, and labor resources, government consumption, infrastructure, minimum wage, education, unemployment, tax rates, consumer price index, inflation, and others), the endogeneity or exogeneity of which are tested in the instrumental variable estimation. Political rights and civil liberties are used as instrumental variables. Results indicate that in the first type, both country institutions and economic factors, specifically labor and logistics/infrastructure/energy intensity, are favorable for potential investors. In the second category of countries, the risk of loss of assets is very high due to governmentshijacked by local oligarchs/cartels/special interest groups. In the third category of countries, the local economic factors are unfavorable for domestic investment even if the institutions are well acceptable. Cluster analysis and instrumental variable estimation were used to reveal cause-effect patterns in each of the clusters.

Keywords: foreign direct investment, economy, institutions, instrumental variable estimation

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215 Potential of Croatia as an Attractive Tourist Destination for the Russian Market

Authors: Maja Martinovic, Valentina Zarkovic, Hrvoje Maljak

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Europe is one of the most popular tourist destinations in the world, in which tourism occupies a significant place among the most relevant economic activities, and this applies to the Republic of Croatia as well. Based on this study, the authors intended to encourage and support the creation of an effective tourism policy in Croatia that would be based on the profiling of certain target groups. Another objective was to compare the results obtained from the customer analysis with the market analysis of the tourism industry in Croatia. The objective is to adapt the current tourist offer according to the identified needs and expectations of a particular tourist group in order to increase the attractiveness of Croatia as a tourist destination and motivate greater attendance of the targeted tourist groups. The current research was oriented towards the Russian market as the target group. Therefore, the authors wanted to encourage a discussion on how to attract more Russian guests. Consequently, the intention of the research was a detailed analysis of Russian tourists, in order to gain a better understanding of their travelling motives and tendencies. Furthermore, attention was paid to the expectations of Russian customers and to compare them with the Croatian tourist offer, and to determine whether there is a possibility for an overlap. The method used to obtain the information required was a survey conducted among Russian citizens about their travelling habits. The research was carried out on the basis of 166 participants of different age, gender, profession and income group. The sampling and distribution of the survey took place between May and July 2016. The results provided from the research indicate that Croatian tourism has certain unrealized potential considering the popularization of Croatia as a tourist destination, and there is a capacity for increasing the revenues within the group of Russian tourists. Such a conclusion is based on the fact that the Croatian tourist offer and the preferences of the Russian guests are compatible, i.e. they overlap in many aspects. The results demonstrate that beautiful nature, cultural and historical heritage as well as the sun and sea, play a leading role in attracting more Russian tourists. It is precisely these elements that form the three pillars of the Croatian tourist offer. On the other hand, the profiling revealed that the most desirable destinations for the Russian guests are Italy and Spain, both of which provide the same main tourist attractions as Croatia. Therefore, the focus of the strategic ideas given in the paper shifted to other tourism segments, such as type of accommodation, sales channels, travel motives, additional offer and seasonality etc., in order to gain advantage in the Russian market, the Mediterranean region and tourism in general. The purpose of the research is to serve as a foundation for analysing the attractiveness of the other tourist destinations in the Russian market, as well as to be a general basis for a more detailed profiling of the various specific target groups of the Russian and other tourist groups.

Keywords: Croatia, Russian market, target groups, tourism, tourist destination

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214 Development of High-Efficiency Down-Conversion Fluoride Phosphors to Increase the Efficiency of Solar Panels

Authors: S. V. Kuznetsov, M. N. Mayakova, V. Yu. Proydakova, V. V. Pavlov, A. S. Nizamutdinov, O. A. Morozov, V. V. Voronov, P. P. Fedorov

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Increase in the share of electricity received by conversion of solar energy results in the reduction of the industrial impact on the environment from the use of the hydrocarbon energy sources. One way to increase said share is to improve the efficiency of solar energy conversion in silicon-based solar panels. Such efficiency increase can be achieved by transferring energy from sunlight-insensitive areas of work of silicon solar panels to the area of their photoresistivity. To achieve this goal, a transition to new luminescent materials with the high quantum yield of luminescence is necessary. Improvement in the quantum yield can be achieved by quantum cutting, which allows obtaining a quantum yield of down conversion of more than 150% due to the splitting of high-energy photons of the UV spectral range into lower-energy photons of the visible and near infrared spectral ranges. The goal of present work is to test approach of excitation through sensibilization of 4f-4f fluorescence of Yb3+ by various RE ions absorbing in UV and Vis spectral ranges. One of promising materials for quantum cutting luminophores are fluorides. In our investigation we have developed synthesis of nano- and submicron powders of calcium fluoride and strontium doped with rare-earth elements (Yb: Ce, Yb: Pr, Yb: Eu) of controlled dimensions and shape by co-precipitation from water solution technique. We have used Ca(NO3)2*4H2O, Sr(NO3)2, HF, NH4F as precursors. After initial solutions of nitrates were prepared they have been mixed with fluorine containing solution by dropwise manner. According to XRD data, the synthesis resulted in single phase samples with fluorite structure. By means of SEM measurements, we have confirmed spherical morphology and have determined sizes of particles (50-100 nm after synthesis and 150-300 nm after calcination). Temperature of calcination appeared to be 600°C. We have investigated the spectral-kinetic characteristics of above mentioned compounds. Here the diffuse reflection and laser induced fluorescence spectra of Yb3+ ions excited at around 4f-4f and 4f-5d transitions of Pr3+, Eu3+ and Ce3+ ions in the synthesized powders are reported. The investigation of down conversion luminescence capability of synthesized compounds included measurements of fluorescence decays and quantum yield of 2F5/2-2F7/2 fluorescence of Yb3+ ions as function of Yb3+ and sensitizer contents. An optimal chemical composition of CaF2-YbF3- LnF3 (Ln=Ce, Eu, Pr), SrF2-YbF3-LnF3 (Ln=Ce, Eu, Pr) micro- and nano- powders according to criteria of maximal IR fluorescence yield is proposed. We suppose that investigated materials are prospective in solar panels improvement applications. Work was supported by Russian Science Foundation grant #17-73- 20352.

Keywords: solar cell, fluorides, down-conversion luminescence, maximum quantum yield

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