Search results for: nuclear emergency

Authors: Hao Qu, Xiang Liu, Michael Crosby, Brian Kozak, Andreas K. Freund

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The outstanding performance of highly oriented pyrolytic graphite (HOPG) as an optical element for neutron beam conditioning is unequaled by any other crystalline material in the applications of monochromator, analyzer, and filter. This superiority stems from the favorable nuclear properties of carbon (small absorption and incoherent scattering cross-sections, big coherent scattering length) and the specific crystalline structure (small thermal diffuse scattering cross-section, layered crystal structure). The real crystal defect structure revealed by imaging techniques is correlated with the parameters used in the mosaic model (mosaic spread, mosaic block size, uniformity). The diffraction properties (rocking curve width as determined by both the intrinsic mosaic spread and the diffraction process, peak and integrated reflectivity, filter transmission) as a function of neutron wavelength or energy can be predicted with high accuracy and reliability by diffraction theory using empirical primary extinction coefficients extracted from a great amount of existing experimental data. The results of these calculations are given as graphs and tables permitting to optimize HOPG characteristics (mosaic spread, thickness, curvature) for any given experimental situation.

Keywords: neutron optics, pyrolytic graphite, mosaic spread, neutron scattering, monochromator, analyzer

Procedia PDF Downloads 135

Authors: M. Hadi Kusuma, Nandy Putra, Anhar Riza Antariksawan, Ficky Augusta Imawan

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Heat pipe is considered to be applied as a passive system to remove residual heat that generated from reactor core when incident occur or from spent fuel storage pool. The objectives are to characterized the heat transfer phenomena, performance of heat pipe, and as a model for large heat pipe will be applied as passive cooling system on nuclear spent fuel pool storage. In this experimental wickless heat pipe or two-phase closed thermosyphon (TPCT) is used. Variation of heat flux are 611.24 Watt/m² - 3291.29 Watt/m². Variation of filling ratio are 45 - 70%. Variation of initial pressure are -62 to -74 cm Hg. Demineralized water is used as working fluid in the TPCT. The results showed that increasing of heat load leads to an increase of evaporation of the working fluid. The optimum filling ratio obtained for 60% of TPCT evaporator volume, and initial pressure variation gave different TPCT wall temperature characteristic. TPCT showed best performance with 60% filling ratio and can be consider to be applied as passive residual heat removal system or passive cooling system on spent fuel storage pool.

Keywords: two-phase closed term syphon, heat pipe, passive cooling, spent fuel storage pool

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Authors: Kiran Kumar K., Ramesh Babu Bejjam, Atul Najan

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A thermosyphon system is a heat transfer loop which operates on the basis of gravity and buoyancy forces. It guarantees a good reliability and low maintenance cost as it does not involve any mechanical pump. Therefore it can be used in many industrial applications such as refrigeration and air conditioning, electronic cooling, nuclear reactors, geothermal heat extraction, etc. But flow instabilities and loop configuration are the major problems in this system. Several previous researchers studied that stabilities can be suppressed by using nanofluids as loop fluid. In the present study a rectangular thermosyphon loop with end heat exchangers are considered for the study. This configuration is more appropriate for many practical applications such as solar water heater, geothermal heat extraction, etc. In the present work, steady-state analysis is carried out on thermosyphon loop with parallel flow coaxial heat exchangers at heat source and heat sink. In this loop nano fluid is considered as the loop fluid and water is considered as the external fluid in both hot and cold heat exchangers. For this analysis one-dimensional homogeneous model is developed. In this model, conservation equations like conservation of mass, momentum, energy are discretized using finite difference method. A computer code is written in MATLAB to simulate the flow in thermosyphon loop. A comparison in terms of heat transfer is made between water and nano fluid as working fluids in the loop.

Keywords: heat exchanger, heat transfer, nanofluid, thermosyphon loop

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Authors: Maatouk Mohamed, Nouira Mariem

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Background and aims: Healthcare-associated infections (HAI) represent a major public health problem worldwide. They represent one of the most serious adverse events in health care. The objectives of our study were to estimate the prevalence of HAI at the Charles Nicolle Hospital (CNH) and to identify the main associated factors as well as to estimate the frequency of antibiotic use. Methods: It was a cross sectional study at the CNH with a unique passage per department (OctoberDecember 2018). All patients present at the wards for more than 48 hours were included. All patients from outpatient consultations, emergency and dialysis departments were not included. The site definitions of infections proposed by the Centers for Disease Control and Prevention (CDC) were used. Only clinically and/or microbiologically confirmed active HAIs were included. Results: A total of 318 patients were included with a mean age of 52 years and a sex ratio (Female/Male) of 1.05. A total of 41 patients had one or more active HAIs, corresponding to a prevalence of 13.1% (95% CI: 9.3%-16.9%). The most frequent sites infections were urinary tract infections and pneumonia. Multivariate analysis among adult patients (>=18 years) (n=261), revealed that infection on admission (p=0.01), alcoholism (p=0.01), high blood pressure (p=0.008), having at least one invasive device inserted (p=0.004), and history of recent surgery (p=0.03), increased significantly the risk of HAIs. More than 1 of 3 patients (35.4%) were under antibiotics on the day of the survey, of which more than half (57.4%) were under 2 or more types of antibiotics. Conclusion: The prevalence of HAIs and antibiotic prescriptions at the CNH were considerably high. An infection prevention and control committee, as well as the development of an Antibiotic stewardship program with continuous monitoring using repeated prevalence surveys must be implemented to limit the frequency of these infections effectively.

Keywords: tumors, oesophagectomy, esophagogastric junction, systematic review

Procedia PDF Downloads 78

Authors: Mazita Mohd Diah, Anton V. Dolzhenko, Tin Wui Wong

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Nanoparticles, being small with a large specific surface area, increase solubility, enhance bioavailability, improve controlled release and enable precision targeting of the entrapped compounds. In this study, chitosan as polymeric permeation enhancer was conjugated to a polar pro-drug, carboxymethyl-5-fluorouracil (CMFU) to increase the skin drug permeation. Chitosan-CMFU conjugate was synthesized using chemical conjugation process through succinate linker. It was then transformed into nanoparticles via spray drying method. The conjugation was elucidated using Fourier Transform Infrared and Proton Nuclear Magnetic Resonance techniques. The nanoparticle size, size distribution, zeta potential, drug content, skin permeation and retention profiles were characterized. The conjugation was denoted using 1H NMR by new peaks at signal δ = 4.184 ppm (singlet, 2H for CH2) and 7.676-7.688 ppm (doublet, 1H for C6) attributed to CMFU in chitosan-CMFU NMR spectrum. The nanoparticles had profiles of particle size: 93.97 ±35.11 nm, polydispersity index: 0.40 ± 0.14, zeta potential: +18.25 ±2.95 mV and drug content: 6.20 ± 1.98 % w/w. Almost 80 % w/w CMFU in the form of nanoparticles permeated through the skin in 24 hours and close to 50 % w/w permeation occurred in first 1-2 hours. Without conjugation to chitosan and nanoparticulation, less than 40 % w/w CMFU permeated through the skin in 24 hours. The skin drug retention likewise was higher with chitosan-CMFU nanoparticles (15.34 ± 5.82 % w/w) than CMFU (2.24 ± 0.57 % w/w). CMFU, through conjugation with chitosan permeation enhancer and processed in nanogeometry, had its skin permeation and retention degree promoted.

Keywords: carboxymethyl-5-fluorouracil, chitosan, conjugate, skin permeation, skin retention

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Authors: Ojetunde Ojewola, Mark Morgan, Sonja Wilhelm-Stanis

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State parks and historic sites are vulnerable to extreme weather events which can affect visitor experiences, management priorities, and legislative requests for disaster relief funds. Recently, global attention has been focused on the perceptions of global warming and how the presence of extreme weather events might impact protected areas, both now and in the future. The effects of climate change are not equally distributed across the United States, leading to varied perceptions based on personal experience with extreme weather events. This study describes employee perceptions of vulnerability and resilience in Missouri State Parks & Historic Sites due to extreme weather events that occur across the state but grouped according to physiographic provinces. Using a four-point rating scale, perceptions of vulnerability and resilience were divided into high and low sub-groups, thus allowing researchers to construct a two by two typology of employee responses. Subsequently, this data was used to develop a three-point continuum of environmental concern (higher scores meant more concern). Employee scores were then compared against a statewide assessment which combined social, economic, infrastructural and environmental indicators of vulnerability and resilience. State park employees thought the system was less vulnerable and more resilient to climate change than data found in statewide assessment This result was also consistent in three out of five physiographic regions across Missouri. Implications suggest that Missouri state park should develop a climate change adaptation strategy for emergency preparedness.

Keywords: extreme weather events, resilience, state parks, vulnerability

Procedia PDF Downloads 117

Authors: Khodzhaberdi Allaberdiev

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Substituted phenols are widely used for the synthesis of advanced polycondensation polymers. In terms of the structure regularity and practical value of obtained polymers are of special interest the p-substituted phenols. The lanthanide induced shifts (LIS) of the aromatic ring and the OH protons by addition Eu(fod)3 to various p-substituted phenols in CDCL3 solvent were measured Nuclear Magnetic Resonance spectroscopy. A linear relationship has been observed between the LIS of protons (∆=δcomplex –δsubstrate) and Eu(fod)3/substrate molar ratios. The LIS protons of the investigated phenols decreases in the following order: ОН > ortho > meta. The LIS of these protons also depends on both steric and electronic effects of p-substituents. The effect on the LIS of protons steric hindrance of substituents by way of example p-substituted alkyl phenols was studied. Alkyl phenols exhibit pronounced europium- induced shifts, their sensitivity increasing in the order: CH3 > C2H5 > sym-C5H11 > tert-C5H11 > tert-C4H9, i.e. in parallel with decreasing steric hindrance. The influence steric hindrance p-substituents of phenols on the LIS of protons in sequence following decreases: OH> meta >ortho. Contrary to the expectations, it is found that the LIS of the ortho protons an excellent linear correlation with meta-substituent constants, σm for 14 p-substituted phenols: ∆H2, 6=8.165-9.896 σm (r2=0,999). Moreover, a linear correlation between the LIS of the ortho protons and ionization constants, РКa of p-substituted phenols has been revealed. Similarly, the linear relationships for the LIS of the meta and the OH protons were obtained. Use the LIS of the phenolic hydroxyl groups for linear relationships is necessary with care, because of the signal broadening of the OH protons. New constants may be determinate with unusual case by this approach.

Keywords: novel correlations, NMR spectroscopy, phenols, shift reagent

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Authors: Enjia Zhang

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During the prevention and control of the COVID-19 pandemic, all communities in China were gated and under strict management, which was highly effective in preventing the spread of the epidemic from spreading. Based on the TRIZ theory, this paper intends to propose green design strategies of community control in response to public health emergencies and to optimize community control facilities according to the principle of minimum transformation. Through the questionnaire method, this paper investigates and summarizes the situation and problems of community control during the COVID-19 pandemic. Based on these problems, the TRIZ theory is introduced to figure out the problems and associates them with prefabricated facilities. Afterward, the innovation points and solutions of prefabricated community control measures are proposed by using the contradiction matrix. This paper summarizes the current situation of community control under public health emergencies and concludes the problems such as simple forms of temporary roadblocks, sudden increase of community traffic pressure, and difficulties to access public spaces. The importance of entrance and exit control in community control is emphasized. Therefore, the community control measures are supposed to focus on traffic control, and the external access control measures, including motor vehicles, non-motor vehicles, residents and non-residents access control, and internal public space access control measures, including public space control shared with the society or adjacent communities, are proposed in order to make the community keep the open characteristics and have the flexibility to deal with sudden public health emergencies in the future.

Keywords: green design, community control, prefabricated structure, public health emergency

Procedia PDF Downloads 124

Authors: Saveria Capecchi

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The aim of the quali-quantitative research conducted in the spring of 2021 (still in the midst of the Covid-19 emergency) was to analyze the relationship between the imaginary of 142 girls aged 10-12 from two Italian cities in the Emilia-Romagna region (the capital, Bologna, and Parma) and the influence that various socialization agents can have on it, with particular attention to social media. In order to investigate the relationship between imagination and media, two tools were used: first, the girls wrote an essay in class about their future lives, imagining waking up one morning as a thirty-year-old adults. Six types of "dreams" reflecting the values and lifestyles characteristic of contemporary Italian society emerged. Additionally, the girls completed a questionnaire on their leisure time and, in particular, media consumption aimed at identifying their favorite characters. The results provided insights into understanding the reference values and lifestyles that define their subculture (they belong to the so-called Generation Z). Another interesting aspect of this research is the possibility of comparing the results with those of a similar study on preadolescent imaginary conducted in 1995, involving 292 girls from Milan and Bologna, belonging to the Millennial generation. The narratives about the imagined adult life reflect some crucial changes undergone by Italian society in a quarter of a century: there are advancements towards gender equality, and the imagined family is increasingly detached from tradition. There is a more persistent dream of a life marked by beauty, wealth, and fame, while at the same time, there is a greater social commitment, from solidarity with marginalized people to environmentalism. Furthermore, the mentioned new digital and robotic professions will project us into the near future.

Keywords: gender equality, gender stereotypes, imaginary, preadolescents, social media

Procedia PDF Downloads 48

Authors: Saimir Heta, Kastriot Haxhirexha, Virtut Velmishi, Nevila Alliu, Ilma Robo

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Background: Testicular rotation can occur at any age. The possibility to save the testicle is the fastest possible surgical intervention which is indicated by the presence of acute pain even at rest. The time element is more important to diagnose and proceed further with surgical intervention. Testicular damage is a consequence which mainly depends on the moment of onset of symptoms, at the time when the symptoms are diagnosed, the earliest action to be performed is surgical intervention. Sometimes medical tests are needed to confirm a diagnosis, or to help identify another cause for symptoms; for example, the urine test, that is used to check for infection, associated with the scrotal ultrasound test. Control of blood flow to the longitudinal supply vessels of the testicles is indicated. The sign that indicates testicular rotation is a reduction in blood flow. This is the element which is distinguished from ultrasound examination. Surgery may be needed to determine if the patient’s symptoms are caused by the rotation of the testis or any other condition. Discussion: As a surgical intervention of the emergency, the torsion of the test depends very much on the duration of the torsion, as the success in the life of the testicle depends on the fastest surgical intervention. From the previous clinic, it is noted that in any case presented to the pediatric patient diagnosed with testicular rotation, there is always a link with personal history that the patient refers to the presence of a previous episode of testicular trauma. Literature supports this fact very logically. Conclusions: Salvation without testicular atrophy depends closely on establishing the diagnosis of testicular rotation as soon as possible. Following the logic above, it can be said that the diagnosis for rotation should be performed as soon as possible, to avoid consequences that will not be favorable for the patient.

Keywords: acute scrotum, test torsion, newborns, clinical presentation

Procedia PDF Downloads 146

Authors: Anjelika Kremer, Irina Nachimov, Dan Justo

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Background: C-reactive protein (CRP) serum levels are commonly measured in hospitalized patients. Elevated admission CRP serum levels and in-hospital mortality has been seldom studied in the general population of elderly patients admitted to the acute Geriatrics department. Methods: A retrospective cross-sectional study was conducted at a tertiary medical center. Included were all elderly patients (age 65 years or more) admitted to a single acute Geriatrics department from the emergency room between April 2014 and January 2015. CRP serum levels were measured routinely in all patients upon the first 24 hours of admission. A logistic regression analysis was used to study if admission CRP serum levels were associated with in-hospital mortality independent of age, gender, functional status, and co-morbidities. Results: Overall, 498 elderly patients were included in the analysis: 306 (61.4%) female patients and 192 (38.6%) male patients. The mean age was 84.8±7.0 years (median: 85 years; IQR: 80-90 years). The mean admission CRP serum levels was 43.2±67.1 mg/l (median: 13.1 mg/l; IQR: 2.8-51.7 mg/l). Overall, 33 (6.6%) elderly patients died during the hospitalization. A logistic regression analysis showed that in-hospital mortality was independently associated with history of stroke (p < 0.0001), heart failure (p < 0.0001), and admission CRP serum levels (p < 0.0001) – and to a lesser extent with age (p = 0.042), collagen vascular disease (p=0.011), and recent venous thromboembolism (p=0.037). Receiver operating characteristic (ROC) curve showed that admission CRP serum levels predict in-hospital mortality fairly with an area under the curve (AUC) of 0.694 (p < 0.0001). Cut-off value with maximal sensitivity and specificity was 19.7 mg/L. Conclusions: Admission CRP serum levels may be used to predict in-hospital mortality in the general population of elderly patients admitted to the acute Geriatrics department.

Keywords: c-reactive protein, elderly, mortality, prediction

Procedia PDF Downloads 233

Authors: Rafiqul Tarefder, Mohiuddin Ahmad, Mohammad Hossain

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While milling materials from old pavement surface can be an important component of cost effective maintenance operation, their use in maintenance projects are not uniform and well documented. This study documents the different maintenance practices followed by four transportation districts of New Mexico Department of Transportation (NMDOT) in an attempt to find whether millings are being used in maintenance projects by those districts. Based on existing literature, a questionnaire was developed related to six common maintenance practices. NMDOT district personal were interviewed face to face to discuss and get answers to that questionnaire. It revealed that NMDOT districts mainly use chip seal and patching. Other maintenance procedures such as sand seal, scrub seal, slurry seal, and thin overlay have limited use. Two out of four participating districts do not have any documents on chip sealing; rather they employ the experiences of the chip seal crew. All districts use polymer modified high float emulsion (HFE100P) for chip seal with an application rate ranging from 0.4 to 0.56 gallons per square yard. Chip application rate varies from 15 to 40 lb/ square yard. State wide, the thickness of chip seal varies from 3/8" to 1" and life varies from 3 to 10 years. NMDOT districts mainly use three type of patching: pothole, dig-out and blade patch. Pothole patches are used for small potholes and during emergency, dig-out patches are used for all type of potholes sometimes after pothole patching, and blade patch is used when a significant portion of the pavement is damaged. Pothole patches last as low as three days whereas, blade patch lasts as long as 3 years. It was observed that all participating districts use millings in maintenance projects.

Keywords: chip seal, sand seal, scrub seal, slurry seal, overlay, patching, millings

Procedia PDF Downloads 336

Authors: Hadas Sopher, Davide Schaumann, Yehuda E. Kalay

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This paper addresses the shortcomings of architectural computation tools in representing human behavior in built environments, prior to construction and occupancy of those environments. Evaluating whether a design fits the needs of its future users is currently done solely post construction, or is based on the knowledge and intuition of the designer. This issue is of high importance when designing complex buildings such as hospitals, where the quality of treatment as well as patient and staff satisfaction are of major concern. Existing computational pre-occupancy human behavior evaluation methods are geared mainly to test ergonomic issues, such as wheelchair accessibility, emergency egress, etc. As such, they rely on Agent Based Modeling (ABM) techniques, which emphasize the individual user. Yet we know that most human activities are social, and involve a number of actors working together, which ABM methods cannot handle. Therefore, we present an event-based model that manages the interaction between multiple Actors, Spaces, and Activities, to describe dynamically how people use spaces. This approach requires expanding the computational representation of Actors beyond their physical description, to include psychological, social, cultural, and other parameters. The model presented in this paper includes cognitive abilities and rules that describe the response of actors to their physical and social surroundings, based on the actors’ internal status. The model has been applied in a simulation of hospital wards, and showed adaptability to a wide variety of situated behaviors and interactions.

Keywords: agent based modeling, architectural design evaluation, event modeling, human behavior simulation, spatial cognition

Procedia PDF Downloads 255

Authors: Muhammad R. Islam, Mohammad Dalour H. Beg, Saidatul S. Jamari

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Considering palm oil as non-drying oil owing to its low iodine value, an attempt was taken to increase the unsaturation in the fatty acid chains of palm oil for the preparation of alkyds. To increase the unsaturation in the palm oil, sulphuric acid (SA) and para-toluene sulphonic acid (PTSA) was used prior to alcoholysis for the dehydration process. The iodine number of the oil samples was checked for the unsaturation measurement by Wijs method. Alkyd resin was prepared using the dehydrated palm oil by following alcoholysis and esterification reaction. To improve the film properties 0.5 wt% multi-wall carbon nano tubes (MWCNTs) were used to manufacture polymeric film. The properties of the resins were characterized by various physico-chemical properties such as density, viscosity, iodine value, acid value, saponification value, etc. Structural elucidation was confirmed by Fourier transform of infrared spectroscopy and proton nuclear magnetic resonance; surfaces of the cured films were observed by scanning electron microscopy. In addition, pencil hardness and chemical resistivity was also measured by using standard methods. The effect of enhancement of the unsaturation in the fatty acid chain found significant and motivational. The resin prepared with dehydrated palm oil showed improved properties regarding hardness and chemical resistivity testing. The incorporation of MWCNTs enhanced the thermal stability and hardness of the films as well.

Keywords: alkyd resin, nano-coatings, dehydration, palm oil

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Authors: Julius Ilawe Osayi, Peter Osifo

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Solid waste disposal, such as used tires is a global challenge as well as energy crisis due to rising energy demand amidst price uncertainty and depleting fossil fuel reserves. Therefore, the effectiveness of pyrolysis as a disposal method that can transform used tires into liquid fuel and other end-products has made the process attractive to researchers. Although used tires have been converted to liquid fuel using pyrolysis, there is the need to improve on the liquid fuel properties. Hence, this paper reports the investigation of zeolite NaY synthesized from kaolin, a locally abundant soil material in the Benin metropolis as a suitable catalyst and its effect on the properties of pyrolytic oil produced from used tires. The pyrolysis process was conducted for a range of 1 to 10 wt.% of catalyst concentration to used tire at a temperature of 600 oC, a heating rate of 15oC/min and particle size of 6mm. Although no significant increase in pyrolytic oil yield was observed compared to the previously investigated non-catalytic pyrolysis of a used tire. However, the Fourier transform infrared (FTIR), Nuclear Magnetic Resonance (NMR); and Gas chromatography-mass spectrometry (GC-MS) characterization results revealed the pyrolytic oil to possess an improved physicochemical and fuel properties alongside valuable industrial chemical species. This confirms the possibility of transforming kaolin into a catalyst suitable for improved fuel properties of the liquid fraction obtainable from thermal cracking of hydrocarbon materials.

Keywords: catalytic pyrolysis, fossil fuel, kaolin, pyrolytic oil, used tyres, Zeolite NaY

Procedia PDF Downloads 174

Authors: Madikeri Rohit

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As energy efficiency is the key concern in many aircraft manufacturing companies regenerative braking is a technique using which energy lost due to friction while braking can be regained. In the operation of an aircraft, significant energy is lost during deceleration or braking which occurs during its landing phase. This problem can be overcome using Regenerative Breaking System (RBS) in landing gear. The major problem faced is regarding the batteries and the overall efficiency gained in competence with the added weight. As the amount of energy required to store is huge we need batteries with high capacity for storage. Another obstacle by using high capacity batteries is the added weight which undermines the efficiency obtained using RBS. An approach to this problem is to either use the obtained energy immediately without storage or to store in other forms such as mechanical, pneumatic and hydraulic. Problem faced with mechanical systems is the weight of the flywheel needed to obtain required efficiency. Pneumatic and hydraulic systems are a better option at present. Using hydraulic systems for storing energy is efficient as it integrates into the overall hydraulic system present in the aircraft. Another obstacle is faced with the redundancy of this system. Conventional braking must be used along with RBS in order to provide redundancy. Major benefits obtained using RBS is with the help of the energy obtained during landing which can be used of engine less taxing. This reduces fuel consumption as well as noise and air pollution. Another added benefit of using RBS is to provide electrical supply to lighting systems, cabin pressurization system and can be used for emergency power supply in case of electric failure. This paper discusses about using RBS in landing gear, problems, prospects and new techniques being pursued to improve RBS.

Keywords: regenerative braking, types of energy conversion, landing gear, energy storage

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Authors: Aleksandra Twarda, Dobrosława Krzemień, Grzegorz Dubin, Tad A. Holak

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Stabilin-2 belongs to the group of scavenger receptors and plays a crucial role in clearance of more than 10 ligands from the bloodstream, including hyaluronic acid, products of degradation of extracellular matrix and metabolic products. The Link domain, a defining feature of stabilin-2, has a sequence similar to Link domains in other hyaluronic acid receptors, such as CD44 or TSG-6, and is responsible for most of ligands binding. Present knowledge of signal transduction by stabilin-2, as well as ligands’ recognition and binding mechanism, is limited. Until now, no experimental structures have been solved for any segments of stabilin-2. It has recently been demonstrated that the stabilin-2 knock-out or blocking of the receptor by an antibody effectively opposes cancer metastasis by elevating the level of circulating hyaluronic acid. Moreover, loss of expression of stabilin-2 in a peri-tumourous liver correlates with increased survival. Solving of the crystal structure of stabilin-2 and elucidation of the binding mechanism of hyaluronic acid could enable the precise characterization of the interactions in the binding site. These results may allow for designing specific small-molecule inhibitors of stabilin-2 that could be used in cancer therapy. To carry out screening for crystallization of stabilin-2, we cloned constructs of the Link domain of various lengths with or without surrounding domains. The folding properties of the constructs were checked by nuclear magnetic resonance (NMR). It is planned to show the binding of hyaluronic acid to the Link domain using several biochemical methods, i.a. NMR, isothermal titration calorimetry and fluorescence polarization assay.

Keywords: stabilin-2, Link domain, X-ray crystallography, NMR, hyaluronic acid, cancer

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Authors: R. Fernandez-Saavedra, M. B. Gomez-Mancebo, D. Gomez-Briceno

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The gradual corrosion of PWR (Pressurized Water Reactor) feedwater, condensate and drain systems results in the inevitable liberation of corrosion products, principally metallic oxides, to the secondary circuit. In addition, other contaminants and impurities are introduced into the makeup water, auxiliary feedwater and by condenser leaks. All these compounds circulating in the secondary flow can eventually be transported to steam generators and be transformed into deposits on their surfaces. Deposits that accumulate on the tube sheet are known as sludge piles and when they consolidate and harden become into hard sludge. Hard sludge is especially detrimental because it favors tube deformation or denting at the top of tube sheet and further stress corrosion cracking (SCC). These failures affect the efficiency of nuclear power plants. In a recent work, a model for the formation and consolidation of hard sludge has been formulated, highlighting the influence of aluminum and silicon compounds in the initial formation of hard sludge. In this work, an experimental study has been performed in order to get a deeper understanding of the behavior of Al and Si species in hard sludge formation and consolidation. For this purpose, the key components of hard sludge (magnetite, aluminum and/or silicon sources) have been isothermally autoclaved in representative secondary circuit conditions during one week, and the resulting products have been chemically and structurally characterized by XRF and XRD techniques, respectively.

Keywords: consolidation, hard sludge, secondary circuit, steam generator

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Authors: Chaitanya R. Mali, V. Vinod, Ashwin W. Patwardhan

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Design of long vertical steam generator (SG) tubes in nuclear power plant involves an understanding of different aspects of flow boiling phenomenon such as flow instabilities, flow regimes, dry out, critical heat flux, pressure drop, etc. The knowledge of the prediction of local thermal hydraulic characteristics is necessary to understand these aspects. For this purpose, the methodology has been developed which covers all the flow boiling regimes to model full range flow boiling phenomenon. In this methodology, the vertical tube is divided into four sections based on vapor fraction value at the end of each section. Different modeling strategies have been applied to the different sections of the vertical tube. Computational fluid dynamics simulations have been performed on a vertical SG tube of 0.0126 m inner diameter and 23 m length. The thermal hydraulic parameters such as vapor fraction, liquid temperature, heat transfer coefficient, pressure drop, heat flux distribution have been analyzed for different designed heat duties (1.1 MW (20%) to 3.3 MW (60%)) and flow conditions (10 % to 80 %). The sensitivity of different boiling parameters such as bubble departure diameter, nucleation site density, bubble departure frequency on the thermal hydraulic parameters was also studied. Flow instability has been observed at 20 % designed heat duty and 20 % flow conditions.

Keywords: thermal hydraulics, boiling, vapor fraction, sensitivity

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Authors: Fatma Koksal Çakirlar, Si̇nem Ozdemir, Selcan Akyol, Revazi̇ye Gulesen, Murat Gunaydin, Nevri̇ye Gonullu, Belkis Levent, Nuri̇ Kiraz

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Vibrio cholerae O1 and O139 are the causative agent of epidemic or pandemic cholera. V. cholerae O1 is generally accepted as a non-invasive enterotoxigenic organism causing gastroenteritis of various severities. Non-O1 V. cholerae can cause small outbreaks of diarrhea due to consumption of contaminated food and water. Particularly, the patients with achlorydria have a risk for vibrio infections. There are numerous case reports of bacteremia caused by vibrio in patients with predisposing conditions like cirrhosis, nephrotic syndrome, diabetes, hematologic malignancy, gastrectomy, and AIDS. We described in this study the first case of nontoxigenic, non-01/non-O139 V. cholerae isolated from the blood culture of a 77-year-old female patient with hipertension, diabetes, coronary artery disease, gout and about 9 years ago migrated breast cancer history. The patient with complaints of shortness of breath, fever and malaise admitted to our emergency clinic were evaluated. There was no diarrhea or abdominal symptoms in the patient. No growth in her urine culture, but blood culture (BACTEC 9120 system, Becton Dickinson, USA) was positive for non-01/non-O139 V. cholerae that was identified by conventional methods and Phoenix automated system (BD Diagnostic Systems, Sparks, MD). It does not secrete the cholera toxin. The agglutination test was negative with polyvalent O1 antisera and O139 antiserum. Empirically ceftriaxone was administered to the patient and she was discharged with improvement in general condition. In this study we report bacteremia by non-01/non-O139 V. cholerae that is rare in the worldwide and first in Turkey.

Keywords: bacteremia, blood culture, immunocompromised patient, Non-O1 vibrio cholerae

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Authors: Sahila Chopra, Hemdeep, Arshdeep Kaur, Raj K. Gupta

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In recent times, we noticed an interesting and important role of non-coplanar degree-of-freedom (Φ = 00) in heavy ion reactions. Using the dynamical cluster-decay model (DCM) with Φ degree-of-freedom included, we have studied three compound systems 246Bk∗, 164Yb∗ and 105Ag∗. Here, within the DCM with pocket formula for nuclear proximity potential, we look for the effects of including compact, non-coplanar configurations (Φc = 00) on the non-compound nucleus (nCN) contribution in total fusion cross section σfus. For 246Bk∗, formed in 11B+235U and 14N+232Th reaction channels, the DCM with coplanar nuclei (Φc = 00) shows an nCN contribution for 11B+235U channel, but none for 14N+232Th channel, which on including Φ gives both reaction channels as pure compound nucleus decays. In the case of 164Yb∗, formed in 64Ni+100Mo, the small nCN effects for Φ=00 are reduced to almost zero for Φ = 00. Interestingly, however, 105Ag∗ for Φ = 00 shows a small nCN contribution, which gets strongly enhanced for Φ = 00, such that the characteristic property of PCN presents a change of behaviour, like that of a strongly fissioning superheavy element to a weakly fissioning nucleus; note that 105Ag∗ is a weakly fissioning nucleus and Psurv behaves like one for a weakly fissioning nucleus for both Φ = 00 and Φ = 00. Apparently, Φ is presenting itself like a good degree-of-freedom in the DCM.

Keywords: dynamical cluster-decay model, fusion cross sections, non-compound nucleus effects, non-coplanarity

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Authors: Nouira Mariem, Ennigrou Samir

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Background and aims: Healthcare-associated infections (HAI) represent a major public health problem worldwide. They represent one of the most serious adverse events in health care. The objectives of our study were to estimate the prevalence of HAI at the Charles Nicolle Hospital (CNH) and to identify the main associated factors as well as to estimate the frequency of antibiotic use. Methods: It was a cross-sectional study at the CNH with a unique passage per department (October-December 2018). All patients present at the wards for more than 48 hours were included. All patients from outpatient consultations, emergency, and dialysis departments were not included. The site definitions of infections proposed by the Centers for Disease Control and Prevention (CDC) were used. Only clinically and/or microbiologically confirmed active HAIs were included. Results: A total of 318 patients were included, with a mean age of 52 years and a sex ratio (female/male) of 1.05. A total of 41 patients had one or more active HAIs, corresponding to a prevalence of 13.1% (95% CI: 9.3%-16.9%). The most frequent site infections were urinary tract infections and pneumonia. Multivariate analysis among adult patients (>=18 years) (n=261) revealed that infection on admission (p=0.01), alcoholism (p=0.01), high blood pressure (p=0.008), having at least one invasive device inserted (p=0.004), and history of recent surgery (p=0.03), increased the risk of HAIs significantly. More than 1 of 3 patients (35.4%) were under antibiotics on the day of the survey, of which more than half (57.4%) were under two or more types of antibiotics. Conclusion: The prevalence of HAIs and antibiotic prescriptions at the CNH were considerably high. An infection prevention and control committee, as well as the development of an antibiotic stewardship program with continuous monitoring using repeated prevalence surveys, must be implemented to limit the frequency of these infections effectively.

Keywords: prevalence, healthcare associated infection, antibiotic, Tunisia

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Authors: Kamel Abd Elaziz Mohamed

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Introduction: Drug related problems (DRPs) are of major concern, affecting patients of both sex. They impose considerable economic burden on the society and the health-care systems. Aim of the work: The aim of this work was to identify and categorize drug-related problems in adult intensive care unit. Patients and methods: The study was a prospective, observational study as eighty six patients were included. They were consecutively admitted to ICU through the emergency room or transferred from the general ward due to DRPs. Parameters included in the study as length of stay in ICU, need for cardiovascular support or mechanical ventilation, dialysis, as well as APACHE II score were recorded. Results: Drug related problems represent 3.6% of the total ICU admission. The median (range) of APACHE II score for 86 patients included in the study was 17 (10-23), and length of ICU stay was 2.4 (1.5-4.2) days. In 45 patients (52%), DRP was drug over dose (group 1), while other DRP was present in the other 41 patients (48%, group 11). Patients in group 1 were older (39 years versus 32 years in group 11), with significant impaired renal function. The need of inotropic drugs and mechanical ventilation as well as the length of stay (LOS) in ICU was significantly higher in group 1. There were no significant difference in GCS between both groups, however APACHE II score was significantly higher in group 1. Only four patients (4.6%) were admitted by suicidal attempt as well as three patients (3.4%) due to trauma drug-related admissions, all were in (group 1). Nineteen percent of the patients had drug related problem due to hypoglycaemic medication followed by tranquilizer (15%). Adverse drug effect followed by failure to receive medication were the most causes of drug problem in (group11).The total mortality rate was 4.6%, all of them were eventually non preventable. Conclusion: The critically ill patients admitted due to drug related problems represented a small proportion (3.6%) of admissions to the ICU. Hypoglycaemic medication was one of the most common causes of admission by drug related problems.

Keywords: drug related problems, ICU, cost, safety

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Authors: Amel M. A. Osman, Roy Mahony, Lisa Dann, McKenna S.

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Background: Computed Tomography (CT) is a significant source of radiation in the pediatric population. A new head injury (HI) pathway was introduced in 2021, which altered the previous process of HI being jointly admitted with general pediatrics and surgery to admit these patients under the Emergency Medicine Team. Admitted patients included those with positive CT findings not requiring immediate neurosurgical intervention and those who did not meet current criteria for urgent CT brain as per NICE guidelines but were still symptomatic for prolonged observations. This approach aims to decrease the number of CT scans performed. The main aim is to assess the variation in CT scanning rates since the change in the admitting process. A retrospective review of patients presenting to CHI PECU with HI over 6-month period (01/01/19-31/05/19) compared to a 6-month period post introduction of the new pathway (01/06/2022-31/12/2022). Data was collected from the electronic record databases, symphony, and PACS. Results: In 2019, there were 869 presentations of HI, among which 32 (3.68%) had CT scans performed. 2 (6.25%) of those scanned had positive findings. In 2022, there were 1122 HI presentations, with 47 (4.19%) CT scans performed and positive findings in 5 (10.6%) cases. 57 patients were admitted under the new pathway for observation, with 1 having a CT scan following admission. Conclusion: Quantitative lifetime radiation risks for children are not negligible. While there was no statistically significant reduction in CTs performed amongst HIs presenting to our department, a significant group met the criteria for admission under the PECU consultant for prolonged monitoring. There was also a greater proportion of abnormalities on CT scans performed in 2022, demonstrating improved patient selection for imaging. Further data analysis is ongoing to determine if those who were admitted would have previously been scanned under the old pathway.

Keywords: head injury, CT, admission, guidline

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Authors: Sahar Heidary, Ramin Ghasemi Shayan

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The recent coronavirus disease 2019 (COVID-19) occurrence has carried considerabletrials to the world health system, comprising the training of dental and maxillofacial radiology (DMFR). DMFR will keep avital role in healthcare throughout this disaster. Severe acute breathing disease coronavirus 2 (SARS-CoV-2), the virus producing the current coronavirus disease 2019 (COVID-19) pandemic, is not only extremely contagious but can make solemn consequences in susceptible persons comprising dental patients and dental health care personnel (DHCPs). Reactions to COVID-19 have been available by the Cores for Infection Switch and Inhibition and the American Dental Association, but a more detailed answer is necessary for the harmless preparation of oral and maxillofacial radiology. Our goal is to evaluation the existing information just how the illness threatens patients and DHCPs and how to define which patients are possible to be SARS-CoV-2 infected; study how the usage of private shielding utensils and contamination control measures based on recent top observes, and knowledge can decrease the danger of virus spread in radiologic trials; and scrutinize how intraoral radiography, with its actually superior danger of scattering the infection, might be changed by extraoralradiographic methods for definite diagnostic jobs. In the pandemic, teleradiology has been extensively recycled for diagnostic determinations of COVID-19 patients, for discussions with radiologists in crisis cases, or managing of distance among radiology clinics. Dentists can have the digital radiographic images of their emergency patients through online service area also by electronic message or messaging applications to view in their smart phones, laptops, or other electronic devices.

Keywords: radiology, dental, oral, COVID-19, infection

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Authors: Maria Medrano, Cristina Cadenas-Sanchez, Maddi Oses, Lide Arenaza, Maria Amasene, Idoia Labayen

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The COVID-19 outbreak began in December 2019 in China and was rapidly expanded globally. Emergency measures, such as social distance or home confinement, were adopted by many country governments to prevent its transmission. In Spain, one of the most affected countries, the schools were closed, and one of the most severe mandatory home confinement was established for children from 14th March to 26th April 2020. The hypothesis of this study was that the measures adopted during the COVID-19 pandemic may have negatively affected physical activity and screen time of children. However, few studies have examined the effects of COVID-19 pandemic on lifestyle behaviours. Thus, the aim of the current work was to analyse the effects of the COVID-19 confinement on physical activity and screen time in Spanish children. For the current purpose, a total of 113 children and adolescents (12.0 ± 2.6 yr., 51.3% boys, 24.0% with overweight/obesity according to the World Obesity Federation) of the MUGI project were included in the analyses. Physical activity and screen time were longitudinally assessed by 'The Youth Activity Profile' questionnaire (YAP). Differences in physical activity and screen time before and during the confinement were assessed by dependent t-test. Before the confinement, 60% did not meet physical activity recommendations ( ≥ 60/min/day of moderate to vigorous physical activity), and 61% used screens ≥ 2 h/day. During the COVID-19 confinement, children decreased their physical activity levels (-91 ± 55 min/day, p < 0.001) and increased screen time ( ± 2.6 h/day, p < 0.001). The prevalence of children that worsened physical activity and screen time during the COVID-19 confinement were 95.2% and 69.8%, respectively. The current study evidence the negative effects of the COVID-19 confinement on physical activity and screen time in Spanish children. These findings should be taken into account to develop and implement future public health strategies for preserving children's lifestyle behaviours and health during and after the COVID-19 pandemic.

Keywords: COVID-19, lifestyle changes, paediatric, physical activity, screen time

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Authors: K. Subermaniam, Q. H. M. Saad, S. N. A. Bakhtiar, J. A. Hamid, F. Z .J. Sidek, F. Othman

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Objective: To investigate the effects of virgin coconut oil (VCO) on histomorphometric changes in the aorta and heart of thermoxidized palm oil-fed rats. Methods: Thirty two male Sprague-Dawley rats were divided into four groups: control group fed with normal diet; 5 times heated palm oil-fed group (5HPO) fortified with 15% w/w of 5HPO; VCO group supplemented with 1.42 ml/kg of VCO; and 5HPO + VCO group. The treatment lasted for four months. Upon sacrifice, aortic and heart tissues were processed for light microscopic studies. Results: Light microscopic studies showed thickened intima and media of the aorta in two out of eight rats in the 5HPO group only, while the rest of the rats did not show any thickening of either the intima or media of the aorta. Intima media area (IMA) in the VCO, 5HPO and 5HPO+VCO was significantly increased compared to the control group. Circumferential wall tension (CWT) and tensile stress (TS) in the aorta of 5HPO showed significant increase compared to the other groups. Cardiomyofibre width in 5HPO group showed significant increase in size compared to the control, VCO and 5HPO+VCO groups. Cardiomyofibre nuclear size in the 5HPO group decreased in size significantly compared to the control, VCO and 5HPO+VCO groups. Conclusion: VCO supplementation at a dose of 1.42 ml/kg showed protectives effect on the aorta and heart of thermoxidized palm oil fed rats.

Keywords: aorta, heart, histomorphometric changes, thermoxidized palm oil, virgin coconut oil

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Authors: Rohit Singh Dangi, Ravi Kant Pal, Monica Sundd

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Acyl-CoA binding protein (ACBP) is a housekeeping protein which functions as an intracellular carrier of acyl-CoA esters. Given the fact that the amastigote stage (blood stage) of Leishmania depends largely on fatty acids as the energy source, of which a large part is derived from its host, these proteins might have an important role in its survival. In Leishmania major, genome sequencing suggests the presence of six ACBPs, whose function remains largely unknown. For functional and structural characterization, one of the ACBP genes was cloned, and the protein was expressed and purified heterologously. Acyl-CoA ester binding and stoichiometry were analyzed by isothermal titration calorimetry and Dynamic light scattering. Our results shed light on high affinity of ACBP towards longer acyl-CoA esters, such as myristoyl-CoA to arachidonoyl-CoA with single binding site. To understand the binding mechanism & dynamics, Nuclear magnetic resonance assignments of this protein are being done. The protein's crystal structure was determined at 1.5Å resolution and revealed a classical topology for ACBP, containing four alpha-helical bundles. In the binding pocket, the loop between the first and the second helix (16 – 26AA) is four residues longer from other extensively studied ACBPs (PfACBP) and it curls upwards towards the pantothenate moiety of CoA to provide a large tunnel space for long acyl chain insertion.

Keywords: acyl-coa binding protein (ACBP), acyl-coa esters, crystal structure, isothermal titration, calorimetry, Leishmania

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Authors: R. Unnikrishnan, K. Shankar

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In the case of high-speed fighter aircrafts, seat ejection is designed mainly for the safety of the pilot in case of an emergency. Strong windblast due to the high velocity of flight is one main difficulty in clearing the tail of the aircraft. Excessive G-forces generated, immobilizes the pilot from escape. In most of the cases, seats are ejected out of the aircrafts by explosives or by rocket motors attached to the bottom of the seat. Ejection forces are primarily in the vertical direction with the objective of attaining the maximum possible velocity in a specified period of time. The safe ejection parameters are studied to estimate the critical time of ejection for various geometries and velocities of flight. An equivalent analytical 2-dimensional biomechanical model of the human spine has been modelled consisting of vertebrae and intervertebral discs with a lumped mass approach. The 24 vertebrae, which consists of the cervical, thoracic and lumbar regions, in addition to the head mass and the pelvis has been designed as 26 rigid structures and the intervertebral discs are assumed as 25 flexible joint structures. The rigid structures are modelled as mass elements and the flexible joints as spring and damper elements. Here, the motions are restricted only in the mid-sagittal plane to form a 26 degree of freedom system. The equations of motions are derived for translational movement of the spinal column. An ejection force with a linearly increasing acceleration profile is applied as vertical base excitation on to the pelvis. The dynamic vibrational response of each vertebra in time-domain is estimated.

Keywords: biomechanical model, lumped mass, seat ejection, vibrational response

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Authors: Tali Capua, Karin Hermon, Miguel Glatstein, Oren Tavor, Ayelet Rimon

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Background: Electric bicycles (E-bikes) are one of a wide range of light electric vehicles that provide convenient local transportation and attractive recreational opportunities. Along with their growing use worldwide, the E-bike related injury rate increases. To the best of our knowledge, this study is the first to specifically compare E-bike with classic bicycle related injuries in children. Methods: Data of all pediatric ( < 16 years of age) bicycle related injuries presenting to an urban level I trauma center between 2014 and 2015 were collected and analyzed. The recorded data included age, gender, details of the accident, as well severity of injury, medical diagnosis, and the outcome. Abbreviated Injury Score (AIS) and Injury Severity Score (ISS) were calculated for each patient. Data of E-bike related injuries and classic bicycle were then compared. Results: A total of 124 bicycle related injuries and 97 E-bike related injuries presented to the emergency department. Once pedestrians and bicycle passengers were removed, the groups of riders consisted of 111 bikers and 85 E-bikers. The mean age of bikers was 9.9 years (range 3-16 years) and of E-bikers was 13.7 years (range 7.5-16 years). Injuries to the head and the extremities were common in both groups. Compared to bikers, E-bikers had significantly more injuries to intra-abdominal organs (p = 0.04). Twenty patients (16%) with bicycle related injuries were admitted, and 13 (15%) patients with E-bike related injuries, of the latter group four underwent surgical intervention. ISS scores were low overall, but the injuries of higher severity (ISS > 9) were among the E-bikers. Conclusions: This study provides unique information which suggests that injuries in E-bikers tend to be more severe than in classic bikers. There is a need for regulation regarding the use of E-bikes to enhance the safety of both bikers and other road and pavement users.

Keywords: bicycle, electric bicycle, injury, pediatric, trauma

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