Search results for: mixed viral infection
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 4449

Search results for: mixed viral infection

3429 Potyviruses Genomic Analysis and Complete Evaluation

Authors: Narin Salehiyan, Ramin Ghasemi Shayan

Abstract:

The largest genus of plant viruses, the potyvirus, is responsible for significant crop losses. Potyviruses are aphid sent in a nonpersistent way, and some of them are likewise seed communicated. As significant microorganisms, potyviruses are substantially more examined than other plant infections having a place with different genera, and their review covers numerous parts of plant virology, like utilitarian portrayal of viral proteins, sub-atomic communication with hosts and vectors, structure, scientific classification, development, the study of disease transmission, and determination. Biotechnological utilizations of potyviruses are likewise being investigated. During this last ten years, significant advances have been made in the comprehension of the sub-atomic science of these infections and the elements of their different proteins. Potyvirus multiplication, movement, and transmission, as well as potyvirus/plant compatible interactions, including pathogenicity and symptom determinants, are updated following a general overview of the family Potyviridae and the potyviral proteins. it end the survey giving data on biotechnological uses of potyviruses.

Keywords: virology, poty, virus, genome, genetic

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3428 Effect of Different Processing Methods on the Proximate, Functional, Sensory, and Nutritional Properties of Weaning Foods Formulated from Maize (Zea mays) and Soybean (Glycine max) Flour Blends

Authors: C. O. Agu, C. C. Okafor

Abstract:

Maize and soybean flours were produced using different methods of processing which include fermentation (FWF), roasting (RWF) and malting (MWF). Products from the different methods were mixed in the ratio 60:40 maize/soybean, respectively. These composites mixed with other ingredients such as sugar, vegetable oil, vanilla flavour and vitamin mix were analyzed for proximate composition, physical/functional, sensory and nutritional properties. The results for the protein content ranged between 6.25% and 16.65% with sample RWF having the highest value. Crude fibre values ranged from 3.72 to 10.0%, carbohydrate from 58.98% to 64.2%, ash from 1.27 to 2.45%. Physical and functional properties such as bulk density, wettability, gelation capacity have values between 0.74 and 0.76g/ml, 20.33 and 46.33 min and 0.73 to 0.93g/ml, respectively. On the sensory quality colour, flavour, taste, texture and general acceptability were determined. In terms of colour and flavour there was no significant difference (P < 0.05) while the values for taste ranged between 4.89 and 7.1 l, texture 5.50 to 8.38 and general acceptability 6.09 and 7.89. Nutritionally there is no significant difference (P < 0.05) between sample RWF and the control in all parameters considered. Samples FWF and MWF showed significantly (P < 0.5) lower values in all parameters determined. In the light of the above findings, roasting method is highly recommend in the production of weaning foods.

Keywords: fermentation, malting, ratio, roasting, wettability

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3427 Review of Consecutive Patients Treated with a Combination of Vancomycin and Rifaximin for Diarrhea Predominant Irritable Bowel Syndrome (IBS-D)

Authors: Portia Murphy, Danica Vasic, Anoja W. Gunaratne, Encarnita Sitchon, Teresita Tugonon, Marou Ison, Antoinette Le Busque, Christelle Pagonis, Thomas J. Borody

Abstract:

Irritable bowel syndrome (IBS) is a chronic gastrointestinal disorder that affects an estimated 11% of the population globally with the most predominant symptoms being abdominal pain, bloating and altered bowel movements. All age groups suffer from IBS although the prevalence of IBS decreases for age groups over 50 years. Women are more likely to suffer from IBS than men. IBS can be categorized into 3 groups based on the type of altered bowel movement: diarrhea-predominant IBS (IBS-D), constipation-predominant IBS (IBS-C) and IBS with mixed bowel habit (IBS-M). The contribution of the gut microbiome to the etiology of IBS is becoming increasingly recognized with rising use of anti-microbial agents. Previous studies on vancomycin and rifaximin used as monotherapy or in combination have been conducted mainly on IBS-C and showed marked improvements in the symptoms. According to our knowledge, no studies reported using these two combinations of antibiotics for IBS-D. Here, we report a consecutive cohort of 18 patients treated with both vancomycin and rifaximin for IBS-D. These patients’ records were reviewed retrospectively. In this cohort, patients ages were between 24-74 years (mean 44 years) and 9 were female. Baseline all patients had diarrhea, 4 with mucus and one with blood. Patients reported other symptoms were abdominal pain (n=11) bloating (n=9), flatulence (n=7), fatigue (n=4) and nausea (n=3). Patients treatments were personalized according to their symptom severity and tolerability and were treated with combination of rifaximin (500 - 3000mg/d) and vancomycin (500mg - 1500mg/d) for an ongoing period. Follow-ups were conducted between 2-32 weeks’ time. Of all patients, 89% patients reported improvement of the symptoms, 1 reported no change and 1 patient’s symptoms got worse. The mechanism of action for both vancomycin and rifaximin involves the inhibition of bacterial cell wall and protein synthesis respectively. The role of these medications in improving the symptoms of this cohort suggests that IBS-D may be microbiome infection driven. In this cohort, similar patient presentations to Clostridium difficile, as well as symptom improvement with the use of rifaximin and particularly vancomycin, suggest that the infectious agent may be an unidentified Clostridium. These preliminary results offer an alternative etiology for IBS-D not previously considered and open the avenue for new research.

Keywords: clostridium deficile, diarrhea predominant Irritable Bowel Syndrome, microbiome, vancomycin/rifaximin combination

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3426 Error Analysis in Academic Writing of EFL Learners: A Case Study for Undergraduate Students at Pathein University

Authors: Aye Pa Pa Myo

Abstract:

Writing in English is accounted as a complex process for English as a foreign language learners. Besides, committing errors in writing can be found as an inevitable part of language learners’ writing. Generally, academic writing is quite difficult for most of the students to manage for getting better scores. Students can commit common errors in their writings when they try to write academic writing. Error analysis deals with identifying and detecting the errors and also explains the reason for the occurrence of these errors. In this paper, the researcher has an attempt to examine the common errors of undergraduate students in their academic writings at Pathein University. The purpose of doing this research is to investigate the errors which students usually commit in academic writing and to find out the better ways for correcting these errors in EFL classrooms. In this research, fifty-third-year non-English specialization students attending Pathein University were selected as participants. This research took one month. It was conducted with a mixed methodology method. Two mini-tests were used as research tools. Data were collected with a quantitative research method. Findings from this research pointed that most of the students noticed their common errors after getting the necessary input, and they became more decreased committing these errors after taking mini-test; hence, all findings will be supportive for further researches related to error analysis in academic writing.

Keywords: academic writing, error analysis, EFL learners, mini-tests, mixed methodology

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3425 Molecular Detection of Helicobacter Pylori and Its Association with TNFα-308 Polymorphism in Cardiovascular Diseases

Authors: Azar Sharafianpor, Hossein Rassi, Fahimeh Nemati Mansur

Abstract:

Cardiovascular diseases (CVD) are the most important cause of death in industrialized and developing countries such as Iran. The most important risk factors for the CVD, genetic factors and chronic infectious agents, such as Helicobacter pylori, can be mentioned. The TNFα gene is one of the most important anti-inflammatory cytokines that can affect the sensitivity, efficacy, and ability of the immune response to chronic infections. Some TNF-α gene polymorphisms, including the replacement of the G nucleotide G with A at position 308 in the promoter region of TNF-α, increase the transcription of cytokines in the target cells and thus predispose a person to chronic infections. This study examines the TNF-α 308 polymorphism and its association with Helicobacter pylori infection in this disease. This study was a case-control study in which 154 patients were examined as cases or patients with symptoms of myocardial infarction or angina and 160 as controls or healthy subjects. All of the subjects at different ages were given venous blood and age, BMI, cholesterol, LDL, and HDL were determined. DNA was extracted from the specimens, and the cagA gene from H. pylori and the TNF-α-308 polymorphism were determined by PCR in patients and healthy subjects. Statistical analysis was performed with Epi Info software. The results showed that the frequency of H. pylori infection in the patients and healthy group were 53.23% (82 out of 154) and 47.5% (76 out of 160). There was no significant difference in H. pylori outbreak between the two groups. The frequencies of TNF-α-308 genotype for GG, GA, and AA in patients were 0.17, 0.49, and 0.34, respectively, whereas for controls 0.47, 0.35, and 0.18 for GG, GA, and AA, respectively. The frequency of genotype analysis of TNF-α-308 polymorphisms in both patients and healthy groups showed that there was a significant difference in the frequency of genotypes and the AA genotype was higher in the affected individuals. Also, there was a significant relationship between the genotype and the contamination with H. pylori and changes in cholesterol, LDL, and HDL levels were observed. The results of the study indicate that H. pylori detection in individuals with AA genotype in people under 50 years of age can play an important role in early diagnosis and treatment of cardiovascular disease.

Keywords: Helicobacter pylori, TNFα gene, cardiovascular diseases, TNFα-308 polymorphism

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3424 Effects of Variable Properties and Double Dispersion on Magnetohydrodynamic (MHD) Mixed Convection in a Power-Law Fluid Saturated Non-Darcy Porous Medium

Authors: Pranitha Janapatla, Venkata Suman Gontla

Abstract:

The present paper investigates the effects of MHD, double dispersion and variable properties on mixed convection flow from a vertical surface in a power-law fluid saturated non-Darcy porous medium. The governing non-linear partial differential equations are reduced to a system of ordinary differential equations by using a special form of Lie group transformations viz. scaling group of transformations. These ordinary differential equations are solved numerically by using Shooting technique. The influence of relevant parameters on the non-dimensional velocity, temperature, concentration for pseudo-plastic fluid, Newtonian and dilatant fluid are discussed and displayed graphically. The behavior of heat and mass transfer coefficients are shown in tabular form. Comparisons with the published works are performed and are found to be in very good agreement. From this analysis, it is observed that an increase in variable viscosity causes to decrease in velocity profile and increase the temperature and concentration distributions. It is also concluded that increase in the solutal dispersion decreases the velocity and concentration but raises the temperature profile.

Keywords: power-law fluid, thermal conductivity, thermal dispersion, solutal dispersion, variable viscosity

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3423 Insomnia and Depression in Outpatients of Dementia Center

Authors: Jun Hong Lee

Abstract:

Background: Many dementia patients complain insomnia and depressive mood, and hypnotics and antidepressants are being prescribed. As prevalence of dementia is increasing, insomnia and depressive mood are becoming more important. Objective: We evaluated insomnia and depression in outpatients of dementia center. Patients and Methods/Material and Methods: We reviewed medical records of the patients who visited outpatients clinic of NHIS Ilsan Hospital Dementia Center during 2016. Results: Total 716 patients are included; Subjective Memory Impairment (SMI) : 143 patients (20%), non-amnestic Mild Cognitive Impairment (MCI): single domain 70 (10%), multiple domain 34 (5%), amnestic MCI: single domain 74 (10%), multiple domain 159 (22%), Early onset Alzheimer´s disease (AD): 9 (1%), AD 121 (17%), Vascular dementia: 62 (9%), Mixed dementia 44 (6%). Hypnotics and antidepressants are prescribed as follows; SMI : hypnotics 14 patients (10%), antidepressants 27 (19%), non-amnestic MCI: single domain hypnotics 9 (13%), antidepressants 12 (17%), multiple domain hypnotics 4 (12%), antidepressants 6 (18%), amnestic MCI: single domain hypnotics 10 (14%), antidepressants 16 (22%), multiple domain hypnotics 22 (14%), antidepressants 24 (15%), Early onset Alzheimer´s disease (AD): hypnotics 1 (11%), antidepressants 2 (22%), AD: hypnotics 10 (8%), antidepressants 36 (30%), Vascular dementia: hypnotics 8 (13%), antidepressants 20 (32%), Mixed dementia: hypnotics 4 (9%), antidepressants 17 (39%). Conclusion: Among the outpatients of Dementia Center, MCI and SMI are majorities, and the number of MCI patients are almost half. Depression is more prevalent in AD, and Vascular dementia than MCI and SMI, and about 22% of patients are being prescribed by antidepressants and 11% by hypnotics.

Keywords: insomnia, depression, dementia, antidepressants, hypnotics

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3422 Plasmodium knowlesi Zoonotic Malaria: An Emerging Challenge of Health Problems in Thailand

Authors: Surachart Koyadun

Abstract:

Currently, Plasmodium knowlesi malaria has spread to almost all countries in Southeast Asia. This research aimed to 1) describe the epidemiology of Plasmodium knowlesi malaria, 2) examine the clinical symptoms of P. knowlesi malaria patients 3) analyze the ecology, animal reservoir and entomology of P. knowlesi malaria. 4) summarize the diagnosis, blood parasites, and treatment of P. knowlesi malaria. The study design was a case report combined with retrospective descriptive survey research. A total of 34 study subjects were patients with a confirmed diagnosis of P. knowlesi malaria who received treatment at hospitals and vector-borne disease control units in Songkhla Province during 2021 – 2022. The results of the epidemiological study unveiled the majority of the samples were male, had a history of staying overnight in the forest before becoming sick, the source of the infection was in the forest, and the season during which they were sick was mostly summer. The average length of time from the onset of illness until receiving a blood test was 3.8 days. The average length of hospital stay was 4 days. Patients were treated with Chloroquine Phosphate, Primaquine, Artesunate, Quinine, and Dihydroartemisinin-piperaquine (40 mg DHA-320 mg PPQ). One death was seen in 34 P. knowlesi malaria patients. All remaining patients recovered and responded to treatment. All symptoms improved after drug administration. No treatment failures were found. Analyses of ecological, zoonotic and entomological data revealed an association between infected patients and forested, monkey-hosted and mosquito-transmitted areas. The recommendation from this study was that the Polymerase Chain Reaction (PCR) method should be used in conjunction with the Thick/Thin Film test and blood parasite test (Parasitaemia) for the specificity of the infection, accuracy of diagnosis, leading to treatment of disease in a timely manner and be effective in disease control.

Keywords: human malaria, Plasmodium knowlesi, zoonotic disease, diagnosis and treatment, epidemiology, ecology

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3421 Healthy Feeding and Drinking Troughs for Profitable Intensive Deep-Litter Poultry Farming

Authors: Godwin Ojochogu Adejo, Evelyn UnekwuOjo Adejo, Sunday UnenwOjo Adejo

Abstract:

The mainstream contemporary approach to controlling the impact of diseases among poultry birds rely largely on curative measures through the administration of drugs to infected birds. Most times as observed in the deep liter poultry farming system, entire flocks including uninfected birds receive the treatment they do not need. As such, unguarded use of chemical drugs and antibiotics has led to wastage and accumulation of chemical residues in poultry products with associated health hazards to humans. However, wanton and frequent drug usage in poultry is avoidable if feeding and drinking equipment are designed to curb infection transmission among birds. Using toxicological assays as guide and with efficiency and simplicity in view, two newly field-tested and recently patented equipments called 'healthy liquid drinking trough (HDT)' and 'healthy feeding trough (HFT)' that systematically eliminate contamination of the feeding and drinking channels, thereby, curbing wide-spread infection and transmission of diseases in the (intensive) deep litter poultry farming system were designed. Upon combined usage, they automatically and drastically reduced both the amount and frequency of antibiotics use in poultry by over > 50%. Additionally, they conferred optimization of feed and water utilization/elimination of wastage by > 80%, reduced labour by > 70%, reduced production cost by about 15%, and reduced chemical residues in poultry meat or eggs by > 85%. These new and cheap technologies which require no energy input are likely to elevate safety of poultry products for consumers' health, increase marketability locally and for export, and increase output and profit especially among poultry farmers and poor people who keep poultry or inevitably utilize poultry products in developing countries.

Keywords: healthy, trough, toxicological, assay-guided, poultry

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3420 Occupational Health Services (OHS) in Hong Kong Hospitals and the Experience of Nurses: A Mixed Methods Study

Authors: Wong Yat Cheung Maggie

Abstract:

Occupational Safety and Health Ordinance (OS&HO) (Chap 509) was enacted in 1997, OHS in HK should be growing and maturing, with a holistic approach to occupational health and safety in the workplace including physical, mental, social and spiritual well-being. The question is “How effective are OHSPs in meeting the current needs of HK health workers?” This study was designed to explore the issue for the first time, to empirically analyse the views of those who work in the system. The study employed a mixed method approach to collect various data from Occupational Health Service Providers (OHSPs), Occupational Health Service Consumers (OHSC): Registered nurses working in the hospital setting. This study was designed in two phases and two stages. Phase I Stage I was a paper survey to collect the data on OHSP. Then Phase I Stage II was a follow-up interview. Phase II Stage I was a paper survey to collect the data on OHSC. Then Phase II Stage II was a follow-up focus group study on OHSC for further clarification of the Phase II and Stage I result. The Phase I result reflects HK OHSPs point of view and their experience in the existing OHS practice in the local hospitals. It reflects various styles of reporting systems, staff profiles background and resource in providing OHS in HK hospitals. However, the basic OHS concern is similar between hospitals. In general, the OHS policies and procedures are available on site even though they may have different foci. The Phase II result is reflecting the HKs OHSCs echoes the OHSP feedback at providing of OHS, OHS concern and related policies and procedure are available on site. However, the most significant feedback from the OHSC at Phase II Stage II shows, nurses experienced various OHS concern most commonly work stress, workplace harassment and back strain without formal or official report to the related parties. The lack of reporting was due to the management handling attitude, stakeholders’ compliance and term of definition still have room to be improved even the related policies and procedures are available on site.

Keywords: occupational health service, registered nurse, Hong Kong hospital, mixed method

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3419 Cybernetic Modeling of Growth Dynamics of Debaryomyces nepalensis NCYC 3413 and Xylitol Production in Batch Reactor

Authors: J. Sharon Mano Pappu, Sathyanarayana N. Gummadi

Abstract:

Growth of Debaryomyces nepalensis on mixed substrates in batch culture follows diauxic pattern of completely utilizing glucose during the first exponential growth phase, followed by an intermediate lag phase and a second exponential growth phase consuming xylose. The present study deals with the development of cybernetic mathematical model for prediction of xylitol production and yield. Production of xylitol from xylose in batch fermentation is investigated in the presence of glucose as the co-substrate. Different ratios of glucose and xylose concentrations are assessed to study the impact of multi substrate on production of xylitol in batch reactors. The parameters in the model equations were estimated from experimental observations using integral method. The model equations were solved simultaneously by numerical technique using MATLAB. The developed cybernetic model of xylose fermentation in the presence of a co-substrate can provide answers about how the ratio of glucose to xylose influences the yield and rate of production of xylitol. This model is expected to accurately predict the growth of microorganism on mixed substrate, duration of intermediate lag phase, consumption of substrate, production of xylitol. The model developed based on cybernetic modelling framework can be helpful to simulate the dynamic competition between the metabolic pathways.

Keywords: co-substrate, cybernetic model, diauxic growth, xylose, xylitol

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3418 Closed Incision Negative Pressure Therapy Dressing as an Approach to Manage Closed Sternal Incisions in High-Risk Cardiac Patients: A Multi-Centre Study in the UK

Authors: Rona Lee Suelo-Calanao, Mahmoud Loubani

Abstract:

Objective: Sternal wound infection (SWI) following cardiac operation has a significant impact on patient morbidity and mortality. It also contributes to longer hospital stays and increased treatment costs. SWI management is mainly focused on treatment rather than prevention. This study looks at the effect of closed incision negative pressure therapy (ciNPT) dressing to help reduce the incidence of superficial SWI in high-risk patients after cardiac surgery. The ciNPT dressing was evaluated at 3 cardiac hospitals in the United Kingdom". Methods: All patients who had cardiac surgery from 2013 to 2021 were included in the study. The patients were classed as high risk if they have two or more of the recognised risk factors: obesity, age above 80 years old, diabetes, and chronic obstructive pulmonary disease. Patients receiving standard dressing (SD) and patients using ciNPT were propensity matched, and the Fisher’s exact test (two-tailed) and unpaired T-test were used to analyse categorical and continuous data, respectively. Results: There were 766 matched cases in each group. Total SWI incidences are lower in the ciNPT group compared to the SD group (43 (5.6%) vs 119 (15.5%), P=0.0001). There are fewer deep sternal wound infections (14(1.8%) vs. 31(4.04%), p=0.0149) and fewer superficial infections (29(3.7%) vs. 88 (11.4%), p=0.0001) in the ciNPT group compared to the SD group. However, the ciNPT group showed a longer average length of stay (11.23 ± 13 days versus 9.66 ± 10 days; p=0.0083) and higher mean logistic EuroSCORE (11.143 ± 13 versus 8.094 ± 11; p=0.0001). Conclusion: Utilization of ciNPT as an approach to help reduce the incidence of superficial and deep SWI may be effective in high-risk patients requiring cardiac surgery.

Keywords: closed incision negative pressure therapy, surgical wound infection, cardiac surgery complication, high risk cardiac patients

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3417 Mathematical Modeling and Analysis of COVID-19 Pandemic

Authors: Thomas Wetere

Abstract:

Background: The coronavirus disease 2019 (COVID-19) pandemic (COVID-19) virus infection is a severe infectious disease with the highly transmissible variant, which become the global public health treat now. It has taken the life of more than 4 million people so far. What makes the disease the worst of all is no specific effective treatment available, its dynamics is not much researched and understood. Methodology: To end the global COVID-19 pandemic, implementation of multiple population-wide strategies, including vaccination, environmental factors, Government action, testing, and contact tracing, is required. In this article, a new mathematical model incorporating both temperature and government action to study the dynamics of the COVID-19 pandemic has been developed and comprehensively analysed. The model considers eight stages of infection: susceptible (S), infected Asymptomatic and Undetected(IAU ), infected Asymptomatic and detected(IAD), infected symptomatic and Undetected(ISU ), infected Symptomatic and detected(ISD), Hospitalized or threatened(H), Recovered(R) and Died(D). Results: The existence as well as non-negativity of the solution to the model is also verified, and the basic reproduction number is calculated. Besides, stability conditions are also checked, and finally, simulation results are compared with real data. The results demonstrates that effective government action will need to be combined with vaccination to end the ongoing COVID-19 pandemic. Conclusion: Vaccination and Government action are highly the crucial measures to control the COVID-19 pandemic. Besides, as the cost of vaccination might be high, we recommend an optimal control to reduce the cost and number of infected individuals. Moreover, in order to prevent COVID-19 pandemic, through the analysis of the model, the government must strictly manage the policy on COVID-19 and carry it out. This, in turn, helps for health campaigning and raising health literacy which plays a role to control the quick spread of the disease. We finally strongly believe that our study will play its own role in the current effort of controlling the pandemic.

Keywords: modeling, COVID-19, MCMC, stability

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3416 Theory of Negative Trigger: The Contract between Oral Probiotics and Immune System

Authors: Cliff Shunsheng Han

Abstract:

Identifying the direct allergy cause that can be easily mitigated is the foundation to stop the allergy epidemic that has been started in the seventies. It has confirmed that the personal and social hygiene practices are associated with the allergy prevalence. But direct causes have been found, and proposed translational measures have not been effective. This study, assisted by a particular case of allergies, has seen the direct cause of allergies, developed a valid test resulted in lasting relief for allergies, and constructed theory describing general relationship between microbiota and host immune system. Saliva samples were collected from a subject for three years during which time the person experienced yearlong allergy, seasonal allergy, and remission of allergy symptoms. Bacterial DNA was extracted and 16S rRNA genes were profiled with Illumina sequencing technology. The analyzing results indicate that the possible direct cause of allergy is the lacking probiotic bacteria in the oral cavity, such as genera Streptococcus and Veilonella, that can produce metabolites to pacify immune system. Targeted promotion of those bacteria with a compound designed for them, has led to lasting remissions of allergic rhinitis. During the development of the translational measure, the subject's oral biofilm was completely destructed by a moderate fever due to an unrelated respiratory infection. The incident not only facilitated the development of the heat based microbiota reseeding procedure but also indicated a possible natural switch that subsequently increases the efficacy of the immune system previously restrained by metabolites from microbiota. These results lead to the proposal of a Theory of Negative Trigger (TNT) to describe the relationship between oral probiotics and immune system, in which probiotics are the negative trigger that will release the power of immune system when removed by fever or modern lifestyles. This study could open doors leading to further understanding of how the immune system functions under the influence of microbiota as well as validate simple traditional practices for healthy living.

Keywords: oral microbiome, allergy, immune system, infection

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3415 Acute Hepatitis A Outbreak in Men Who Has Sex with Men in a Medical Center in Northern Taiwan

Authors: Yu-Tzu Hsu, Alice Wu, Hsiang-Kuang Tseng

Abstract:

Introduction: Hepatitis A virus causes acute hepatitis and is usually transmitted by a fecal-oral route of food contamination, which is more prevalent in areas with poor hygienic practices. However, we described a hepatitis A outbreak associated with a fecal-oral route of sexual behavior in men who has sex with men (MSM) in Northern Taiwan. Methods: We retrospectively collected patients with acute HAV infection in MacKay Memorial Hospital, Taipei, Taiwan between July 2015 and November 2016. Demographic data (age, gender, onset time and infection risk), laboratory data (GOT, GPT, bilirubin, HIV status, HBsAg, HCV antibody and syphilis), clinical symptoms and travel history with a foreign tour were analyzed. We compared variables between HIV and non-HIV group. Unless otherwise stated, continuous variables were expressed as mean ± SD, and categorical variables were expressed as number (percentage) for each item. The t test for continuous variables was applied for the comparison between two groups and chi-square for categorical variables were applied for measures of association. Results: We collected 80 cases during the study period. Among them, 54 (67.5%) cases were MSM and 43 (53.8%) cases were HIV positive. The average age was 32.6±7.59 years-old. The average value of initial liver function was 1324 IU/L for AST (GOT), 2100 IU/L for ALT (GPT), and 5.82 mg/dL for bilirubin. We found seven (8.6%) cases were in the status of HBV carrier, five (6.3%) cases were positive for HCV antibody, and 15 (18.6%) cases were co-infected with syphilis. With regards to associated symptoms, 32 (40%) had fever, 46 (57.5%) had nausea, 34 (42.5%) had abdominal discomfort and 46 (57.5%) had general malaise. To compare the non-HIV patients with HIV patients, HIV patients were more likely to be male (p=0.008), MSM (p=0.000), co-infected syphilis (p=0.000) and slowly improving liver function of transaminases (p=0.033, 0.027). Conclusion: The HAV outbreak in Northern Taiwan was mainly occurred in MSM population. Hereafter, our cohort data support a policy in Taiwan to provide one dose of free HAV vaccine shot in this population. Hopefully, the outbreak could be stop by the free vaccine policy and public education.

Keywords: acute hepatitis A, men who has sex with men, human immunodeficiency virus, vaccine

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3414 Studies on Interaction between Anionic Polymer Sodium Carboxymethylcellulose with Cationic Gemini Surfactants

Authors: M. Kamil, Rahber Husain Khan

Abstract:

In the present study, the Interaction of anionic polymer, sodium carboxymethylcellulose (NaCMC), with cationic gemini surfactants 2,2[(oxybis(ethane-1,2-diyl))bis(oxy)]bis(N-hexadecyl1-N,N-[di(E2)/tri(E3)]methyl1-2-oxoethanaminium)chloride (16-E2-16 and 16-E3-16) and conventional surfactant (CTAC) in aqueous solutions have been studied by surface tension measurement of binary mixtures (0.0- 0.5 wt% NaCMC and 1 mM gemini surfactant/10 mM CTAC solution). Surface tension measurements were used to determine critical aggregation concentration (CAC) and critical micelle concentration (CMC). The maximum surface excess concentration (Ґmax) at the air-water interface was evaluated by the Gibbs adsorption equation. The minimum area per surfactant molecule was evaluated, which indicates the surfactant-polymer Interaction in a mixed system. The effect of changing surfactant chain length on CAC and CMC values of mixed polymer-surfactant systems was examined. From the results, it was found that the gemini surfactant interacts strongly with NaCMC as compared to its corresponding monomeric counterpart CTAC. In these systems, electrostatic interactions predominate. The lowering of surface tension with an increase in the concentration of surfactants is higher in the case of gemini surfactants almost 10-15 times. The measurements indicated that the Interaction between NaCMC-CTAC resulted in complex formation. The volume of coacervate increases with an increase in CTAC concentration; however, above 0.1 wt. % concentration coacervate vanishes.

Keywords: anionic polymer, gemni surfactants, tensiometer, CMC, interaction

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3413 Bio-Nano Mask: Antivirus and Antimicrobial Mouth Mask Coating with Nano-TiO2 and Anthocyanin Utilization as an Effective Solution of High ARI Patients in Riau

Authors: Annisa Ulfah Pristya, Andi Setiawan

Abstract:

Indonesia placed in sixth rank total Acute Respiratory Infection (ARI) patient in the world and Riau as one of the province with the highest number of people with respiratory infection in Indonesia reached 37 thousand people. Usually society using a mask as prevention action. Unfortunately the commercial mouth mask only can work maximum for 4 hours and the pores are too large to filter out microorganisms and viruses carried by infectious droplets nucleated 1-5 μm. On the other hand, Indonesia is rich with Titanium dioxide (TiO2) and purple sweet potato anthocyanin pigment. Therefore, offered Bio-nano-mask which is a antimicrobial and antiviral mouth mask with Nano-TiO2 coating and purple sweet potato anthocyanins utilization as an effective solution to high ARI patients in Riau, which has the advantage of the mask surface can’t be attached by infectious droplets, self-cleaning and have anthocyanins biosensors that give visual response can be understood easily by the general public in the form of a mask color change from blue/purple to pink when acid levels increase. Acid level is an indicator of microorganisms accumulation in the mouth and surrounding areas. Bio-nano mask making process begins with the preparation (design, Nano-TiO2 liquid preparation, anthocyanins biosensors manufacture) and then superimposing the Nano-TiO2 on the outer surface of spunbond color using a sprayer, then superimposing anthocyanins biosensors film on the Meltdown surface, making bio nano-mask and it pack. Bio-nano mask has the advantage is effectively preventing pathogenic microorganisms and infectious droplets and has accumulated indicator microorganisms that color changes which easily observed by the common people though.

Keywords: anthocyanins, ARI, nano-TiO2 liquid, self cleaning

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3412 Cyclone Driven Variation of Chlorophyll-a Concentration in Bay of Bengal

Authors: Nowshin Nabila Siddique, S. M. Mustafizur Rahman

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There is evidence of cyclonic events in Bay of Bengal (BoB) throughout the year. These cyclones cause a variety of fluctuations along its track including the is the influence in Chlorophyll-a (chl-a) concentration. The main purpose of this paper is to justify this variation pattern. Six Tropical Cyclones (TC) are studied using observational method. The result suggests that there is a noticeable change in productivity after a cyclone passes, when the pre cyclonic and post cyclonic condition is observed. In case of Cyclone Amphan, it shows 1.79 mg/m3 of chlorophyll-a concentration increase after a week of cyclonic occurrence. This change is affected by several attributes such as translation speed, intensity and Ocean Pre-condition, specifically Mixed Layer Depth (MLD). Translation Speed and MLD shows a strong negative correlation with the induced chlorophyll concentration. Whereas the effect of the intensity on a cyclone is not that prominent. It is also found that the period of starting an induction is not same for all cyclone such as in case of Cyclone Amphan, the changes started to occur after one day however for Cyclone Sidr and Cyclone Mora it started after three days. Furthermore, a slightly increase in overall productivity is also observed after a cyclone. In the case of Cyclone Amphan, Hudhud, Phailin it shows a rise up to 0.12 mg/m3 in productivity which decreases gradually taking around the period of two months. On a whole this paper signifies the changes in chlorophyll concentration caused by numerous cyclones and its different characteristics that regulates these changes.

Keywords: tropical cyclone, chlorophyll-a concentration, mixed layer depth, translation speed

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3411 Epidemiology and Jeopardy Aspect of Febrile Neutropenia Patients by Means of Infectious Maladies

Authors: Pouya Karimi, Ramin Ghasemi Shayan

Abstract:

Conclusions of the sort and setting of observational treatment for immunocompromised patients with fever are confused by the qualities of the hidden disease and the impacts of medications previously got, just as by changing microbiological examples and patterns in sedate obstruction at national and institutional levels. A few frameworks have been proposed to recognize patients who could profit by outpatient anti-infection treatment from patients who require hospitalization. Useful contemplations may choose whether the fundamental checking during the time of neutropenia can be accomplished.

Keywords: microbiology, infectious, neutropenia, epidemiology

Procedia PDF Downloads 164
3410 Age-Associated Seroprevalence of Toxoplasma gondii in 10892 Pregnant Women in Senegal between 2016 and 2019

Authors: Ndiaye Mouhamadou, Seck Abdoulaye, Ndiaye Babacar, Diallo Thierno Abdoulaye, Diop Abdou, Seck Mame Cheikh, Diongue Khadim, Badiane Aida Sadikh, Diallo Mamadou Alpha, Kouedvidjin Ekoué, Ndiaye Daouda

Abstract:

Background: Toxoplasmosis is a parasite disease that presents high rates of gestational and congenital infection worldwide and is therefore considered a public health problem and a neglected disease. The aim of this study was to determine the seroprevalence of toxoplasmosis in pregnant women referred to the medical biology laboratory of the Pasteur Institute of Dakar (Senegal) between January 2014 and December 2019. Methodology: This was a cross-sectional, descriptive, retrospective study of 10892 blood samples from pregnant women aged 16 to 46 years. The Architect toxo IgG/IgM from Abbot Laboratories, which is a chemiluminescent microparticle immunoassay (CMIA), was used for the quantitative determination of antibodies against Toxoplasma gondii in human serum. Results: In total, over a period from January 2014 to December 2019, 10892 requests for toxoplasmosis serology in pregnant women were included. The age of the patients included in our series ranged from 16 to 46 years. The mean age was 31.2 ± 5.72 years. The overall seroprevalence of T. gondii in pregnant women was estimated to be 28.9% [28.0-29.7]. In a multivariate logistic regression analysis, after adjustment for a covariate such as a study period, pregnant women aged 36-46 years were more likely to carry IgG antibodies to T. gondii than pregnant women younger than 36 years. Conclusion: T. gondii seroprevalence was significantly higher in pregnant women older than 36 years, leaving younger women more susceptible to primary T. gondii infection and their babies to congenital toxoplasmosis. There will be a need to increase awareness of the risk factors for toxoplasmosis and its different modes of transmission in these high-risk groups, but this should be supported by epidemiologic studies of the distribution of risk factors for toxoplasmosis in pregnant women and women of childbearing age.

Keywords: toxoplasmosis, pregnancy, seroprevalence, Senegal

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3409 Comprehensive Investigation of Solving Analytical of Nonlinear Differential Equations at Chemical Reactions to Design of Reactors by New Method “AGM”

Authors: Mohammadreza Akbari, Pooya Soleimani Besheli, Reza khalili, Sara Akbari, Davood Domiri Ganji

Abstract:

In this symposium, our aims are accuracy, capabilities and power at solving of the complicate non-linear differential at the reaction chemical in the catalyst reactor (heterogeneous reaction). Our purpose is to enhance the ability of solving the mentioned nonlinear differential equations at chemical engineering and similar issues with a simple and innovative approach which entitled ‘’Akbari-Ganji's Method’’ or ‘’AGM’’. In this paper we solve many examples of nonlinear differential equations of chemical reactions and its investigate. The chemical reactor with the energy changing (non-isotherm) in two reactors of mixed and plug are separately studied and the nonlinear differential equations obtained from the reaction behavior in these systems are solved by a new method. Practically, the reactions with the energy changing (heat or cold) have an important effect on designing and function of the reactors. This means that possibility of reaching the optimal conditions of operation for the maximum conversion depending on nonlinear nature of the reaction velocity toward temperature, results in the complexity of the operation in the reactor. In this case, the differential equation set which governs the reactors can be obtained simultaneous solution of mass equilibrium and energy and temperature changing at concentration.

Keywords: new method (AGM), nonlinear differential equation, tubular and mixed reactors, catalyst bed

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3408 Risk Factors for Acute Respiratory Infection Among Children Under Five in Tanzania: A Systematic Review and Analysis of the 2015 Demographic and Health Survey for Tanzania

Authors: Ayesha Ali, Emilia Lindquist, Arif Jalal, Hannah Yusuf, Kayan Cheung, Rowan Eastabrook

Abstract:

It is currently estimated that over a third of deaths in children under five in Tanzania are caused by acute respiratory infections (ARIs). However, despite being one of the leading causes of morbidity and mortality across the developing world, its risk factors are poorly understood. Therefore, a systematic review of the literature published between 2015 and 2020 was conducted, focusing on risk factors for ARI in Tanzanian children under the age of five. 2015 Demographic and Health Survey (DHS) for Tanzania was analysed to supplement these findings with national data. 2224 papers were retrieved from two databases and were analysed by three independent reviewers. Thirteen papers were eligible for inclusion, covering a wide range of risk factors among which comorbidities (n=6), malnutrition (n=5), lack of parental education (n=4), poor socio-economic status (n=3), and delay in seeking healthcare (n=3) were the most cited risk factors. The risk factors with the highest reported risk ratios/odds ratios were lack of parental education (RR=11.5-14.5), followed by enrolment in school (RR=4.4), delay in seeking healthcare (RR=3.8) and cooking indoors (aOR =1.8-RR=5.5). The DHS data provided local context to these risk factors. For instance, the number of children experiencing symptoms of ARI in both urban and rural areas ranged between 4.5-5% in the two weeks prior to the survey. However, 79% of symptomatic children in Zanzibar received antibiotics for treatment compared to just 34% of those in the Southern Highlands. As demonstrated by both the systematic review and the DHS analysis, risk factors for ARI are predominantly socially determined, with Tanzania’s poorer rural children possessing the highest risk for ARI and more adverse health outcomes. Therefore, the burden of ARIs in Tanzanian children may be alleviated through the provision of appropriate treatment and parental education in rural areas.

Keywords: acute respiratory infection, child, health education, morbidity, mortality, pneumonia, Tanzania

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3407 Inpatient Neonatal Deaths in Rural Uganda: A Retrospective Comparative Mortality Study of Labour Ward versus Community Admissions

Authors: Najade Sheriff, Malaz Elsaddig, Kevin Jones

Abstract:

Background: Death in the first month of life accounts for an increasing proportion of under-five mortality. Advancement to reduce this number is being made across the globe; however, progress is slowest in sub-Saharan Africa. Objectives: The study aims to identify differences between neonatal deaths of inpatient babies born in a hospital facility in rural Uganda to those of neonates admitted from the community and to explore whether they can be used to risk stratify neonatal admissions. Results: A retrospective chart review was conducted on records for neonates admitted to the Special Care Baby Unit (SCBU) Kitovu Hospital from 1st July 2016 to 21st July 2017. A total of 442 babies were admitted and the overall neonatal mortality was 24.8% (40% inpatient, 37% community, 23% hospital referrals). 40% of deaths occurred within 24 hours of admission and the majority were male (63%). 43% of babies were hypothermic upon admission, a significantly greater proportion of which were inpatient babies born in labour ward (P=0.0025). Intrapartum related death accounted for ½ of all inpatient babies whereas complications of prematurity were the predominant cause of death in the community group (37%). Severe infection does not seem like a significant factor of mortality for inpatients (2%) as it does for community admissions (29%). Furthermore, with 52.5% of community admissions weighing < 1500g, very low birth weight (VLBW) may be a significant risk factor for community neonatal death. Conclusion: The neonatal mortality rate in this study is high, and the leading causes of death are all largely preventable. A high rate of inpatient birth asphyxiation indicates the need for good quality facility-based perinatal care as well as a greater focus on the management of hypothermia, such as Kangaroo care. Moreover, a reduction in preterm deliveries is necessary to reduce associated comorbidities, and monitoring for signs of infection is especially important for community admissions.

Keywords: community, mortality, newborn, Uganda

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3406 Two-Dimensional Analysis and Numerical Simulation of the Navier-Stokes Equations for Principles of Turbulence around Isothermal Bodies Immersed in Incompressible Newtonian Fluids

Authors: Romulo D. C. Santos, Silvio M. A. Gama, Ramiro G. R. Camacho

Abstract:

In this present paper, the thermos-fluid dynamics considering the mixed convection (natural and forced convections) and the principles of turbulence flow around complex geometries have been studied. In these applications, it was necessary to analyze the influence between the flow field and the heated immersed body with constant temperature on its surface. This paper presents a study about the Newtonian incompressible two-dimensional fluid around isothermal geometry using the immersed boundary method (IBM) with the virtual physical model (VPM). The numerical code proposed for all simulations satisfy the calculation of temperature considering Dirichlet boundary conditions. Important dimensionless numbers such as Strouhal number is calculated using the Fast Fourier Transform (FFT), Nusselt number, drag and lift coefficients, velocity and pressure. Streamlines and isothermal lines are presented for each simulation showing the flow dynamics and patterns. The Navier-Stokes and energy equations for mixed convection were discretized using the finite difference method for space and a second order Adams-Bashforth and Runge-Kuta 4th order methods for time considering the fractional step method to couple the calculation of pressure, velocity, and temperature. This work used for simulation of turbulence, the Smagorinsky, and Spalart-Allmaras models. The first model is based on the local equilibrium hypothesis for small scales and hypothesis of Boussinesq, such that the energy is injected into spectrum of the turbulence, being equal to the energy dissipated by the convective effects. The Spalart-Allmaras model, use only one transport equation for turbulent viscosity. The results were compared with numerical data, validating the effect of heat-transfer together with turbulence models. The IBM/VPM is a powerful tool to simulate flow around complex geometries. The results showed a good numerical convergence in relation the references adopted.

Keywords: immersed boundary method, mixed convection, turbulence methods, virtual physical model

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3405 A Study on Children's Literature for Multiracial Asian American Children

Authors: Kaori Mori Want

Abstract:

American society is a racially diverse society and there are children books that tell the importance of respecting racial differences. Through reading books, children understand the world around them little by little along with their direct interaction with the world in reality. They find role models in books, strive to be like role models, and grow confidence in who they are. Books thus nurture the mind of children. On the other hand, because of their small presence, children books for multiracial Asian American children are scarce. Multiracial Asian American population is increasing but they are still minority in number. The lack of children’s books for these children may deprive the opportunities of them to embrace their multiraciality positively because they cannot find someone like them in any books. Children books for multiracial Asian American are still not that many, but a few have been being published recently. This paper introduces children books for multiracial Asian American children, and examines how they address issues pertaining to these children, and how they could nurture their self-esteem. Many states of the US used to ban interracial marriages and interracial families and their children once were discriminated against in American society. There was even a theory called the hybrid degeneracy theory which claimed that mixed race children were inferior mentally and physically. In this negative social environment, some multiracial Asian American people report that they had trouble embracing their multiracial identity positively. Yet, children books for these children are full of positive messages. This paper will argue the importance of children books for the mental growth of multiracial Asian American children, and how these books can contribute to the development of multiculturalism in the US in general.

Keywords: critical mixed race studies in the US, hapa children literature, interracial marriage, multiraciality

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3404 Prevalence of Dengue in Sickle Cell Disease in Pre-school Children

Authors: Nikhil A. Gavhane, Sachin Shah, Ishant S. Mahajan, Pawan D. Bahekar

Abstract:

Introduction: Millions of people are affected with dengue fever every year, which drives up healthcare expenses in many low-income countries. Organ failure and other serious symptoms may result. Another worldwide public health problem is sickle cell anaemia, which is most prevalent in Africa, the Caribbean, and Europe. Dengue epidemics have reportedly occurred in locations with a high frequency of sickle cell disease, compounding the health problems in these areas. Aims and Objectives: This study examines dengue infection in sickle cell disease-afflicted pre-schoolers. Method:This Retrospective cohort study examined paediatric patients. Young people with sickle cell disease (SCD), dengue infection, and a control group without SCD or dengue were studied. Data on demographics, SCD consequences, medical treatments, and laboratory findings were gathered to analyse the influence of SCD on dengue severity and clinical outcomes, classified as severe or non-severe by the 2009 WHO classification. Using fever or admission symptoms, the research estimated acute illness duration. Result: Table 1 compares haemoglobin genotype-based dengue episode features in SS, SC, and controls. Table 2 shows that severe dengue cases are older, have longer admission delays, and have particular symptoms. Table 3's multivariate analysis indicates SS genotype's high connection with severe dengue, multiorgan failure, and acute pulmonary problems. Table 4 relates severe dengue to greater white blood cell counts, anaemia, liver enzymes, and reduced lactate dehydrogenase. Conclusion: This study is valuable but confined to hospitalised dengue patients with sickle cell illness. Small cohorts limit comparisons. Further study is needed since findings contradict predictions.

Keywords: dengue, chills, headache, severe myalgia, vomiting, nausea, prostration

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3403 Seroprevalence of Middle East Respiratory Syndrome Coronavirus (MERS-Cov) Infection among Healthy and High Risk Individuals in Qatar

Authors: Raham El-Kahlout, Hadi Yassin, Asmaa Athani, Marwan Abou Madi, Gheyath Nasrallah

Abstract:

Background: Since its first isolation in September 2012, Middle East respiratory syndrome coronavirus (MERS-CoV) has diffused across 27 countries infecting more than two thousand individuals with a high case fatality rate. MERS-CoV–specific antibodies are widely found in Dromedary camel along with viral shedding of similar viruses detected in human at same region, suggesting that MERS epidemiology may be central role by camel. Interestingly, MERS-CoV has also been also reported to be asymptomatic or to cause influenza-like mild illnesses. Therefore, in a country like Qatar (bordered Saudi Arabia), where camels are widely spread, serological surveys are important to explore the role of camels in MERS-CoV transmission. However, widespread strategic serological surveillances of MERS-CoV among populations, particularly in endemic country, are infrequent. In the absence of clear epidemiological view, cross-sectional MERS antibody surveillances in human populations are of global concern. Method: We performed a comparative serological screening of 4719 healthy blood donors, 135 baseline case contacts (high risk individual), and four MERS confirmed patients (by PCR) for the presence of anti-MERS IgG. Initially, samples were screened using Euroimmune anti- MERS-CoV IgG ELISA kit, the only commercial kit available in the market and recommended by the CDC as a screening kit. To confirm ELISA test results, farther serological testing was performed for all borderline and positive samples using two assays; the anti MERS-CoV IgG and IgM Euroimmune indirect immunofluorescent test (IIFT) and pseudoviral particle neutralizing assay (PPNA). Additionally, to test cross reactivity of anti-MERS-CoV antibody with other family members of coronavirus, borderline and positive samples were tested for the presence of the of IgG antibody of the following viruses; SARS, HCoV-229E, HKU1 using the Euroimmune IIFT for SARS and HCoV-229E and ELISA for HKU1. Results: In all of 4858 screened 15 samples [10 donors (0.21%, 10/4719), 1 case contact (0.77 %, 1/130), 3 patients (75%, 3/4)] anti-MERS IgG reactive/borderline samples were seen in ELISA. However, only 7 (0.14%) of them gave positive with in IIFT and only 3 (0.06%) was confirmed by the specific anti-MERS PPNA. One of the interesting findings was, a donor, who was selected in the control group as a negative anti-MERS IgG ELISA, yield reactive for anti-MERS IgM IIFT and was confirmed with the PPNA. Further, our preliminary results showed that there was a strong cross reactivity between anti- MERS-COV IgG with both HCoV-229E or anti-HKU1 IgG, yet, no cross reactivity of SARS were found. Conclusions: Our findings suggest that MERS-CoV is not heavily circulated among the population of Qatar and this is also indicated by low number of confirmed cases (only 18) since 2012. Additionally, the presence of antibody of other pathogenic human coronavirus may cause false positive results of both ELISA and IIFT, which stress the need for more evaluation studies for the available serological assays. Conclusion: this study provides an insight about the epidemiological view for MERS-CoV in Qatar population. It also provides a performance evaluation for the available serologic tests for MERS-CoV in a view of serologic status to other human coronaviruses.

Keywords: seroprevalence, MERS-CoV, healthy individuals, Qatar

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3402 Nanofluids and Hybrid Nanofluids: Comparative Study of Mixed Convection in a Round Bottom Flask

Authors: Hicham Salhi

Abstract:

This research project focuses on the numerical investigation of the mixed convection of Hybrid nanofluids in a round bottom flask commonly used in organic chemistry synthesis. The aim of this study is to improve the thermal properties of the reaction medium and enhance the rate of chemical reactions by using hybrid nanofluids. The flat bottom wall of the flask is maintained at a constant high temperature, while the top, left, and right walls are kept at a low temperature. The nanofluids used in this study contain suspended Cu and Al2O3 nanoparticles in pure water. The governing equations are solved numerically using the finite-volume approach and the Boussinesq approximation. The effects of the volume fraction of nanoparticles (φ) ranging from 0% to 5%, the Rayleigh number from 103 to 106, and the type of nanofluid (Cu and Al2O3) on the flow streamlines, isotherm distribution, and Nusselt number are examined in the simulation. The results indicate that the addition of Cu and Al2O3 nanoparticles increases the mean Nusselt number, which improves heat transfer and significantly alters the flow pattern. Moreover, the mean Nusselt number increases with increasing Rayleigh number and volume fraction, with Cu- Al2O3 hybrid nanofluid producing the best results. This research project focuses on the numerical investigation of the mixed convection of Hybrid nanofluids in a round bottom flask commonly used in organic chemistry synthesis. The aim of this study is to improve the thermal properties of the reaction medium and enhance the rate of chemical reactions by using hybrid nanofluids. The flat bottom wall of the flask is maintained at a constant high temperature, while the top, left, and right walls are kept at a low temperature. The nanofluids used in this study contain suspended Cu and Al2O3 nanoparticles in pure water. The governing equations are solved numerically using the finite-volume approach and the Boussinesq approximation. The effects of the volume fraction of nanoparticles (φ) ranging from 0% to 5%, the Rayleigh number from 103 to 106, and the type of nanofluid (Cu and Al2O3) on the flow streamlines, isotherm distribution, and Nusselt number are examined in the simulation. The results indicate that the addition of Cu and Al2O3 nanoparticles increases the mean Nusselt number, which improves heat transfer and significantly alters the flow pattern. Moreover, the mean Nusselt number increases with increasing Rayleigh number and volume fraction, with Cu- Al2O3 hybrid nanofluid producing the best results.

Keywords: bottom flask, mixed convection, hybrid nanofluids, numerical simulation

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3401 Quantitative Analysis of the Functional Characteristics of Urban Complexes Based on Station-City Integration: Fifteen Case Studies of European, North American, and East Asian Railway Stations

Authors: Dai Yizheng, Chen-Yang Zhang

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As station-city integration has been widely accepted as a strategy for mixed-use development, a quantitative analysis of the functional characteristics of urban complexes based on station-city integration is urgently needed. Taking 15 railway stations in European, North American, and East Asian cities as the research objects, this study analyzes their functional proportion, functional positioning, and functional correlation with respect to four categories of functional facilities for both railway passenger flow and subway passenger flow. We found that (1) the functional proportion of urban complexes was mainly concentrated in three models: complementary, dominant, and equilibrium. (2) The mathematical model affected by the functional proportion was created to evaluate the functional positioning of an urban complex at three scales: station area, city, and region. (3) The strength of the correlation between the functional area and passenger flow was revealed via data analysis using Pearson’s correlation coefficient. Finally, the findings of this study provide a valuable reference for research on similar topics in other countries that are developing station-city integration.

Keywords: urban complex, station-city integration, mixed-use, function, quantitative analysis

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3400 Alumina Supported Cu-Mn-La Catalysts for CO and VOCs Oxidation

Authors: Elitsa N. Kolentsova, Dimitar Y. Dimitrov, Petya Cv. Petrova, Georgi V. Avdeev, Diana D. Nihtianova, Krasimir I. Ivanov, Tatyana T. Tabakova

Abstract:

Recently, copper and manganese-containing systems are recognized as active and selective catalysts in many oxidation reactions. The main idea of this study is to obtain more information about γ-Al2O3 supported Cu-La catalysts and to evaluate their activity to simultaneous oxidation of CO, CH3OH and dimethyl ether (DME). The catalysts were synthesized by impregnation of support with a mixed aqueous solution of nitrates of copper, manganese and lanthanum under different conditions. XRD, HRTEM/EDS, TPR and thermal analysis were performed to investigate catalysts’ bulk and surface properties. The texture characteristics were determined by Quantachrome Instruments NOVA 1200e specific surface area and pore analyzer. The catalytic measurements of single compounds oxidation were carried out on continuous flow equipment with a four-channel isothermal stainless steel reactor in a wide temperature range. On the basis of XRD analysis and HRTEM/EDS, it was concluded that the active component of the mixed Cu-Mn-La/γ–alumina catalysts strongly depends on the Cu/Mn molar ratio and consisted of at least four compounds – CuO, La2O3, MnO2 and Cu1.5Mn1.5O4. A homogeneous distribution of the active component on the carrier surface was found. The chemical composition strongly influenced catalytic properties. This influence was quite variable with regards to the different processes.

Keywords: Cu-Mn-La oxide catalysts, carbon oxide, VOCs, deep oxidation

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