Search results for: wake effects
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 10832

Search results for: wake effects

4382 Analgesic Efficacy of Opiorphin and Its Analogue

Authors: Preet Singh, Kavitha Kongara, Dave Harding, Neil Ward, Paul Chambers

Abstract:

The objective of this study was to compare the analgesic efficacy of opiorphin and its analogue with a mu-receptor agonist; morphine. Opiorphins (Gln-Arg-Phe-Ser-Arg) belong to the family of endogenous enkephalinase inhibitors, found in saliva of humans. They are inhibitors of two Zinc metal ectopeptidases (Neutral endopeptidase NEP, and amino-peptidase APN) which are responsible for the inactivation of the endogenous opioids; endorphins and enkephalins. Morphine and butorphanol exerts their analgesic effects by mimicking the actions of endorphins and enkephalins. The opiorphin analogue was synthesized based on the structure activity relationship of the amino acid sequence of opiorphin. The pharmacological profile of the analogue was tested by replacing Serine at position 4 with Proline. The hot plate and tail flick test were used to demonstrate the analgesic efficacy. There was a significant increase in the time for the tail flick response after an injection of opiorphin, which was similar to the morphine effect. There was no increase in time in the hot plate test after an injection of opiorphin. The results suggest that opiorphin works at spinal level only rather than both spinal and supraspinal. Further work is required to confirm our results. We did not find analgesic activity of the opiorphin analogue. Thus, Serine at position 4 is also important for its pharmacological action. Further work is required to illustrate the role of serine at position 4 in opiorphin.

Keywords: analgesic peptides, endogenous opioids, morphine, opiorphin

Procedia PDF Downloads 325
4381 Effects of Transformational Leadership and Political Competition on Corporate Performance of Nigeria National Petroleum Corporation

Authors: Justine Ugochukwu Osuagwu, Sazali Abd Wahab

Abstract:

The performance and operation of NNPC have faced series of attacks by all stakeholders as many have observed lots of inefficiency not only on the part of the management but the staff. This has raised questions of whether their operations and performance are being seriously affected by lack of transformational leadership, and the political competition prevalent in the country. The author has applied the administrative leadership theory and institutional theory as a guide to this study and empirically relates such theories to the study. The study also has utilized the quantitative approach where questionnaires were distributed to 370 participants, and the correctly filled and returned questionnaires were used for the analysis using structural equation modeling. The path coefficient of transformational leadership to performance is strong and positive with β = 0.672; t-value = 14.245; p-value = 0.000. Also, the result found that political competition does not mediate the relationship between transformational leadership and performance of NNPC. (β = -0.008; t-value = -0.600; p- value > 0.05). However, the indirect path is all insignificant, meaning that transformational leadership has relationship with corporate performance.The study found that,while political competition does not serve as a mediator in the relationship between transformational leadership and corporate performance, these styles of leadership have a direct and positive impact on corporate performance. The direct relationship between transformational leadership and political competition was not discovered, despite the fact that political competition has a direct and significant impact, both positive and negative, on corporate performance. As a result, both political competition and transformational leadership have the potential to significantly alter corporate performance.

Keywords: performance, transformational leadership, political competition, corporation performance, Nigeria national petroleum corporation

Procedia PDF Downloads 117
4380 Sensitivity Analysis of Pile-Founded Fixed Steel Jacket Platforms

Authors: Mohamed Noureldin, Jinkoo Kim

Abstract:

The sensitivity of the seismic response parameters to the uncertain modeling variables of pile-founded fixed steel jacket platforms are investigated using tornado diagram, first-order second-moment, and static pushover analysis techniques. The effects of both aleatory and epistemic uncertainty on seismic response parameters have been investigated for an existing offshore platform. The sources of uncertainty considered in the present study are categorized into three different categories: the uncertainties associated with the soil-pile modeling parameters in clay soil, the platform jacket structure modeling parameters, and the uncertainties related to ground motion excitations. It has been found that the variability in parameters such as yield strength or pile bearing capacity has almost no effect on the seismic response parameters considered, whereas the global structural response is highly affected by the ground motion uncertainty. Also, some uncertainty in soil-pile property such as soil-pile friction capacity has a significant impact on the response parameters and should be carefully modeled. Based on the results, it is highlighted that which uncertain parameters should be considered carefully and which can be assumed with reasonable engineering judgment during the early structural design stage of fixed steel jacket platforms.

Keywords: fixed jacket offshore platform, pile-soil structure interaction, sensitivity analysis

Procedia PDF Downloads 375
4379 Selected Ethnomedicinal Plants of Northern Surigao Del Sur: Their Antioxidant Activities in Terms of Total Phenolics, ABTS Radical Cation Decolorization Power, and Ferric Reducing Ability

Authors: Gemma A. Gruyal

Abstract:

Plants can contain a wide variety of substances with antioxidative properties which are associated to important health benefits. These positive health effects are of great importance at a time when the environment is laden with many toxic substances. Five selected herbal plants namely, Mimosa pudica, Phyllanthus niruri, Ceiba pentandra, Eleusine polydactyla and Trema amboinensis, were chosen for the experiment to investigate their total phenolics content and antioxidant activities using ABTS radical cation decolorization power, and ferric reducing antioxidant power. The total phenolic content of each herbal plants ranges from 0.84 to 42.59 mg gallic acid equivalent/g. The antioxidant activity in the ABTS radical cation decolorization power varies from 0.005 to 0.362 mg trolox equivalent/g and the FRAP ranges from 0.30 to 28.42 mg gallic acid equivalent/g. Among the five medicinal plants, Mimosa pudica has been an excellent performer in terms of the 3 parameters measured; it is followed by Phyllanthus niruri. The five herbal plants do not have equivalent antioxidant power. The relative high values for M. pudica and P. niruri supports the medicinal value of both plants. The total phenolics, ABTS and FRAP correlate strongly with one another.

Keywords: ABTS, FRAP, Leaf extracts, phenol

Procedia PDF Downloads 433
4378 Assessment of Land Surface Temperature Using Satellite Remote Sensing

Authors: R. Vidhya, M. Navamuniyammal M. Sivakumar, S. Reeta

Abstract:

The unplanned urbanization affects the environment due to pollution, conditions of the atmosphere, decreased vegetation and the pervious and impervious soil surface. Considered to be a cumulative effect of all these impacts is the Urban Heat Island. In this paper, the urban heat island effect is studied for the Chennai city, TamilNadu, South India using satellite remote sensing data. LANDSAT 8 OLI and TIRS DATA acquired on 9th September 2014 were used to Land Surface Temperature (LST) map, vegetation fraction map, Impervious surface fraction, Normalized Difference Water Index (NDWI), Normalized Difference Building Index (NDBI) and Normalized Difference Vegetation Index (NDVI) map. The relationship among LST, Vegetation fraction, NDBI, NDWI, and NDVI was calculated. The Chennai city’s Urban Heat Island effect is significant, and the results indicate LST has strong negative correlation with the vegetation present and positive correlation with NDBI. The vegetation is the main factor to control urban heat island effect issues in urban area like Chennai City. This study will help in developing measures to land use planning to reduce the heat effects in urban area based on remote sensing derivatives.

Keywords: land surface temperature, brightness temperature, emissivity, vegetation index

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4377 Overview of Multi-Chip Alternatives for 2.5 and 3D Integrated Circuit Packagings

Authors: Ching-Feng Chen, Ching-Chih Tsai

Abstract:

With the size of the transistor gradually approaching the physical limit, it challenges the persistence of Moore’s Law due to the development of the high numerical aperture (high-NA) lithography equipment and other issues such as short channel effects. In the context of the ever-increasing technical requirements of portable devices and high-performance computing, relying on the law continuation to enhance the chip density will no longer support the prospects of the electronics industry. Weighing the chip’s power consumption-performance-area-cost-cycle time to market (PPACC) is an updated benchmark to drive the evolution of the advanced wafer nanometer (nm). The advent of two and half- and three-dimensional (2.5 and 3D)- Very-Large-Scale Integration (VLSI) packaging based on Through Silicon Via (TSV) technology has updated the traditional die assembly methods and provided the solution. This overview investigates the up-to-date and cutting-edge packaging technologies for 2.5D and 3D integrated circuits (ICs) based on the updated transistor structure and technology nodes. The author concludes that multi-chip solutions for 2.5D and 3D IC packagings are feasible to prolong Moore’s Law.

Keywords: moore’s law, high numerical aperture, power consumption-performance-area-cost-cycle time to market, 2.5 and 3D- very-large-scale integration, packaging, through silicon via

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4376 Outdoor Visible Light Communication Channel Modeling under Fog and Smoke Conditions

Authors: Véronique Georlette, Sebastien Bette, Sylvain Brohez, Nicolas Point, Veronique Moeyaert

Abstract:

Visible light communication (VLC) is a communication technology that is part of the optical wireless communication (OWC) family. It uses the visible and infrared spectrums to send data. For now, this technology has widely been studied for indoor use-cases, but it is sufficiently mature nowadays to consider the outdoor environment potentials. The main outdoor challenges are the meteorological conditions and the presence of smoke due to fire or pollutants in urban areas. This paper proposes a methodology to assess the robustness of an outdoor VLC system given the outdoor conditions. This methodology is put into practice in two realistic scenarios, a VLC bus stop, and a VLC streetlight. The methodology consists of computing the power margin available in the system, given all the characteristics of the VLC system and its surroundings. This is done thanks to an outdoor VLC communication channel simulator developed in Python. This simulator is able to quantify the effects of fog and smoke thanks to models taken from environmental and fire engineering scientific literature as well as the optical power reaching the receiver. These two phenomena impact the communication by increasing the total attenuation of the medium. The main conclusion drawn in this paper is that the levels of attenuation due to fog and smoke are in the same order of magnitude. The attenuation of fog being the highest under the visibility of 1 km. This gives a promising prospect for the deployment of outdoor VLC uses-cases in the near future.

Keywords: channel modeling, fog modeling, meteorological conditions, optical wireless communication, smoke modeling, visible light communication

Procedia PDF Downloads 150
4375 Effect of Arbutus Pavarii ( Shemari ) Libyan Medical Plant on Ethylene Glycol Induced Urolithiasis in Male Albino Rats

Authors: Khaled. M.Benelhaj, Moada Elbadary

Abstract:

The present investigation is carried out to evaluate the effect of aqueous extract of Arbutus Pavarii (Shemari) Libyan medical plant on ethylene glycol(EG) induce lithiasis in adult male albino rats. The lithiasis was induced to rats by oral administration of EG (0.75 w/v%) for 21 days(group 1). Aqueous extract of Shemari (200 mg/kg) was given orally from 1st day for preventive regimen (group 2) and from day 21st up to 42nd day for curative regimen (group 3). The results indicated that the EG elevated the urinary ionic of calcium, oxalates and inorganic phosphate. The Shemari significantly (P<0.01) reduced the levels of these ions. The histopathological findings showed that EG caused marked pathological changes in renal cortex; necrosis of glomerular tufts; mildy thickened bowman’s capsule and coagulative necrosis of large number of convoluted tubules. However, the histological changes in preventive regimen group 2 showed the same changes observed in group 1, but milder in severity and less in frequency. It conclude that Shemari do reduce the urinary ionic levels of calcium, oxalates and inorganic phosphate but failed to prevent complete deterioration effects of EG on kidney structures.

Keywords: EG, shamari, kidney stone, Libyan medical plant, glycol, oxalates

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4374 Comparing Groundwater Fluoride Level with WHO Guidelines and Classifying At-Risk Age Groups; Based on Health Risk Assessment

Authors: Samaneh Abolli, Kamyar Yaghmaeian, Ali Arab Aradani, Mahmood Alimohammadi

Abstract:

The main route of fluoride uptake is drinking water. Fluoride absorption in the acceptable range (0.5-1.5 mg L-¹) is suitable for the body, but it's too much consumption can have irreversible health effects. To compare fluoride concentration with the WHO guidelines, 112 water samples were taken from groundwater aquifers in 22 villages of Garmsar County, the central part of Iran, during 2018 to 2019.Fluoride concentration was measured by the SPANDS method, and its non-carcinogenic impacts were calculated using EDI and HQ. The statistical population was divided into four categories of infant, children, teenagers, and adults. Linear regression and Spearman rank correlation coefficient tests were used to investigate the relationships between the well's depth and fluoride concentration in the water samples. The annual mean concentrations of fluoride in 2018 and2019 were 0.75 and 0.64 mg -¹ and, the fluoride mean concentration in the samples classifying the cold and hot seasons of the studied years was 0.709 and 0.689 mg L-¹, respectively. The amount of fluoride in 27% of the samples in both years was less than the acceptable minimum (0.5 mg L-¹). Also, 11% of the samples in2018 (6 samples) had fluoride levels higher than 1.5 mg L-¹. The HQ showed that the children were vulnerable; teenagers and adults were in the next ranks, respectively. Statistical tests showed a reverse and significant correlation (R2 = 0.02, < 0.0001) between well depth and fluoride content. The border between the usefulness/harmfulness of fluoride is very narrow and requires extensive studies.

Keywords: fluoride, groundwater, health risk assessment, hazard quotient, Garmsar

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4373 Investigating the Post-Liver Transplant Complications and Their Management in Children Referred to the Children’s Medical Center

Authors: Hosein Alimadadi, Fatemeh Farahmand, Ali Jafarian, Nasir Fakhar, Mohammad Hassan Sohouli, Neda Raeesi

Abstract:

Backgroundsː Regarding the important role of liver transplantation as the only treatment in many cases of end-stage liver disease in children, the aim of this study is to investigate the complications of liver transplantation and their management in children referred to the Children's Medical Center. Methods: This study is a cross-sectional study on pediatric patients who have undergone liver transplants in the years 2016 to 2021. The indication for liver transplantation in this population was confirmed by a pediatric gastroenterologist, and a liver transplant was performed by a transplant surgeon. Finally, information about the patient before and after the transplantation was collected and recorded. Results: A total of 53 patients participated in this study, including 25 (47.2%) boys and 28 (52.8%) girls. The most common causes of liver transplantation were cholestatic and metabolic diseases. The most common early complication of liver transplantation in children was acute cellular rejection (ACR) and anastomotic biliary stricture. The most common late complication in these patients was an infection which was observed in 56.6% of patients. Among the drug side effects, neurotoxicity (convulsions) was seen more in patients, and 15.1% of the transplanted patients died. Conclusion: In this study, the most common early complication of liver transplantation in children was ACR and biliary stricture, and the most common late complication was infection. Neurotoxicity (convulsions) was the most common side effect of drugs.

Keywords: liver transplantation, complication, infection, survival rate

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4372 Punica granatum (Pomegranate) of a Libyan Variety Exhibits in vitro Anti-Inflammatory Potential

Authors: Lamees A. Ben Saad, Kah Hwi Kim, Chin Chew Quah, Mustafa Shahimi

Abstract:

Background: Punica granatum (pomegranate) was used as a traditional medicine in different parts of the world. It has been used in the treatment of pain and inflammatory conditions such as peptic ulcer. The numerous risks associated with nonsteroidal anti-inflammatory drugs (NSAIDs) for the treatment of pain and inflammation give rise to using medicinal herbs as alternative therapies. This study aimed to evaluate the anti-inflammatory effect of the ethyl acetate pomegranate fraction (EtOAc) by determination of its inhibitory effects on lipopolysaccharide (LPS), stimulated nitric oxide (NO), prostaglandin E2 (PGE-2), interleukin-6 (IL-6) and cyclooxxgenase-2 (COX2) release from RAW264.7cells. Methods: The inhibitory effect of EtOAc was evaluated on (LPS) induced NO production, PGE2, and IL-6 quantified by immunoassay kit and prostaglandin E2 competitive ELISA kit. COX2 production is an in vitro indication of possible anti-inflammatory activity and was estimated by Western blotting. Results: EtOAc potentially inhibited LPS-induced nitric oxide, prostaglandin, and IL-6 production. With these findings, it was evident that the EtOAc could reduce the LPS-induced cyclooxygenase-2 (COX-2) at the protein level in a dose-dependent manner as determined by Western blotting. Conclusion: The results emphasize potential therapeutic applications of Punica granatum in the treatment of inflammation.

Keywords: inflammation, Punica granatum, cytotoxicity, cytokines

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4371 Causes and Effects of the 2012 Flood Disaster on Affected Communities in Nigeria

Authors: Abdulquadri Ade Bilau, Richard Ajayi Jimoh, Adejoh Amodu Adaji

Abstract:

The increasing exposures to natural hazards have continued to severely impair on the built environment causing huge fatalities, mass damage and destruction of housing and civil infrastructure while leaving psychosocial impacts on affected communities. The 2012 flood disaster in Nigeria which affected over 7 million inhabitants in 30 of the 36 states resulted in 363 recorded fatalities with about 600,000 houses and a number of civil infrastructure damaged or destroyed. In Kogi State, over 500 thousand people were displaced in 9 out of the 21 local government affected while Ibaji and Lokoja local governments were worst hit. This study identifies the causes and 2012 flood disasters and its effect on housing and livelihood. Personal observation and questionnaire survey were instruments used in carrying out the study and data collected were analysed using descriptive statistical tool. Findings show that the 2012 flood disaster was aided by the gap in hydrological data, sudden dam failure, and inadequate drainage capacity to reduce flood risk. The study recommends that communities residing along the river banks in Lokoja and Ibaji LGAs must be adequately educated on their exposure to flood hazard and mitigation and risk reduction measures such as construction of adequate drainage channel are constructed in affected communities.

Keywords: flood, hazards, housing, risk reduction, vulnerability

Procedia PDF Downloads 265
4370 Structural Analysis of Hole-Type Plate for Weight Lightening of Road Sign

Authors: Joon-Yeop Na, Sang-Keun Baik, Kyu-Soo Chong

Abstract:

Road sign sizes are related to their support and foundation, and the large-scale support that is generally installed at roadsides can cause inconvenience to pedestrians and damage the urban landscape. The most influential factor in determining the support and foundation of road signs is the wind load. In this study, we introduce a hole-type road sign to analyze its effects on reducing wind load. A hole-type road sign reduces the drag coefficient that is applied when considering the air and fluid resistance of a plate when the wind pressure is calculated, thus serving as an effective option for lightening the weights of road sign structures. A hole-type road sign is punctured with a perforator. Furthermore, the size of the holes and their distance is determined considering the damage to characters, the poor performance of reflective sheets, and legibility. For the calculation of the optimal specification of a hole-type road sign, we undertook a theoretical examination for reducing the wind loads on hole-type road signs, and analyzed the bending and reflectivity of sample road sign plates. The analytic results confirmed that a hole-type road sign sample that contains holes of 6 mm in diameter with a distance of 18 mm between the holes shows reflectivity closest to that of existing road signs; moreover, the average bending moment resulted in a reduction of 4.24%, and the support’s diameter is reduced by 40.2%.

Keywords: hole type, road sign, weight lightening, wind load

Procedia PDF Downloads 546
4369 Effects of Initial Moisture Content on the Physical and Mechanical Properties of Norway Spruce Briquettes

Authors: Miloš Matúš, Peter Križan, Ľubomír Šooš, Juraj Beniak

Abstract:

The moisture content of densified biomass is a limiting parameter influencing the quality of this solid biofuel. It influences its calorific value, density, mechanical strength and dimensional stability as well as affecting its production process. This paper deals with experimental research into the effect of moisture content of the densified material on the final quality of biofuel in the form of logs (briquettes or pellets). Experiments based on the single-axis densification of the spruce sawdust were carried out with a hydraulic piston press (piston and die), where the densified logs were produced at room temperature. The effect of moisture content on the qualitative properties of the logs, including density, change of moisture, expansion and physical changes, and compressive and impact resistance were studied. The results show the moisture ranges required for producing good-quality logs. The experiments were evaluated and the moisture content of the tested material was optimized to achieve the optimum value for the best quality of the solid biofuel. The dense logs also have high-energy content per unit volume. The research results could be used to develop and optimize industrial technologies and machinery for biomass densification to achieve high quality solid biofuel.

Keywords: biomass, briquettes, densification, fuel quality, moisture content, density

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4368 Computational Prediction of the Effect of S477N Mutation on the RBD Binding Affinity and Structural Characteristic, A Molecular Dynamics Study

Authors: Mohammad Hossein Modarressi, Mozhgan Mondeali, Khabat Barkhordari, Ali Etemadi

Abstract:

The COVID-19 pandemic, caused by SARS-CoV-2, has led to significant concerns worldwide due to its catastrophic effects on public health. The SARS-CoV-2 infection is initiated with the binding of the receptor-binding domain (RBD) in its spike protein to the ACE2 receptor in the host cell membrane. Due to the error-prone entity of the viral RNA-dependent polymerase complex, the virus genome, including the coding region for the RBD, acquires new mutations, leading to the appearance of multiple variants. These variants can potentially impact transmission, virulence, antigenicity and evasive immune properties. S477N mutation located in the RBD has been observed in the SARS-CoV-2 omicron (B.1.1. 529) variant. In this study, we investigated the consequences of S477N mutation at the molecular level using computational approaches such as molecular dynamics simulation, protein-protein interaction analysis, immunoinformatics and free energy computation. We showed that displacement of Ser with Asn increases the stability of the spike protein and its affinity to ACE2 and thus increases the transmission potential of the virus. This mutation changes the folding and secondary structure of the spike protein. Also, it reduces antibody neutralization, raising concern about re-infection, vaccine breakthrough and therapeutic values.

Keywords: S477N, COVID-19, molecular dynamic, SARS-COV2 mutations

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4367 A Review of the Relation between Thermofludic Properties of the Fluid in Micro Channel Based Cooling Solutions and the Shape of Microchannel

Authors: Gurjit Singh, Gurmail Singh

Abstract:

The shape of microchannels in microchannel heat sinks can have a significant impact on both heat transfer and fluid flow properties. Heat Transfer, pressure drop, and Some effects of microchannel shape on these properties. The shape of microchannels can affect the heat transfer performance of microchannel heat sinks. Channels with rectangular or square cross-sections typically have higher heat transfer coefficients compared to circular channels. This is because rectangular or square channels have a larger wetted perimeter per unit cross-sectional area, which enhances the heat transfer from the fluid to the channel walls. The shape of microchannels can also affect the pressure drop across the heat sink. Channels with a rectangular cross-section usually have higher pressure drop than circular channels. This is because the corners of rectangular channels create additional flow resistance, which leads to a higher pressure drop. Overall, the shape of microchannels in microchannel heat sinks can have a significant impact on the heat transfer and fluid flow properties of the heat sink. The optimal shape of microchannels depends on the specific application and the desired balance between heat transfer performance and pressure drop.

Keywords: heat transfer, microchannel heat sink, pressure drop, chape of microchannel

Procedia PDF Downloads 90
4366 Assay for SARS-Cov-2 on Chicken Meat

Authors: R. Mehta, M. Ghogomu, B. Schoel

Abstract:

Reports appeared in 2020 about China detecting SARS-Cov-2 (Covid-19) on frozen meat, shrimp, and food packaging material. In this study, we examined the use of swabs for the detection of Covid-19 on meat samples, and chicken breast (CB) was used as a model. Methods: Heat inactivated SARS-Cov-2 virus (IV) from Microbiologics was loaded onto the CB, swabbing was done, and the recovered inactivated virus was subjected to the Machery & Nagel NucleoSpin RNAVirus kit for RNA isolation according to manufacturer's instructions. For RT-PCR, the IDT 2019-nCoV RUO Covid-19 test kit was used with the Taqman Fast Virus 1-step master mix. The limit of detection (LOD) of viral load recovered from the CB was determined under various conditions: first on frozen CB where the IV was introduced on a defined area, then on frozen CB, with IV spread-out, and finally, on thawed CB. Results: The lowest amount of IV which can be reliably detected on frozen CB was a load of 1,000 - 2,000 IV copies where the IV was loaded on one spot of about 1 square inch. Next, the IV was spread out over a whole frozen CB about 16 square inches. The IV could be recovered at a lowest load of 4,000 to 8,000 copies. Furthermore, the effects of temperature change on viral load recovery was investigated i.e., if raw unfrozen meat became contaminated and remains for 1 hour at 4°C or gets refrozen. The amount of IV recovered successfully from CB kept at 4°C and the refrozen CB was similar to the recovery gotten from loading the IV directly on the frozen CB. In conclusion, an assay using swabs was successfully established for the detection of SARS-Cov-2 on frozen or raw (unfrozen) CB with a minimal load of up to 8,000 copies spread over 16 square inches.

Keywords: assay, COVID-19, meat, SARS-Cov-2

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4365 An Overbooking Model for Car Rental Service with Different Types of Cars

Authors: Naragain Phumchusri, Kittitach Pongpairoj

Abstract:

Overbooking is a very useful revenue management technique that could help reduce costs caused by either undersales or oversales. In this paper, we propose an overbooking model for two types of cars that can minimize the total cost for car rental service. With two types of cars, there is an upgrade possibility for lower type to upper type. This makes the model more complex than one type of cars scenario. We have found that convexity can be proved in this case. Sensitivity analysis of the parameters is conducted to observe the effects of relevant parameters on the optimal solution. Model simplification is proposed using multiple linear regression analysis, which can help estimate the optimal overbooking level using appropriate independent variables. The results show that the overbooking level from multiple linear regression model is relatively close to the optimal solution (with the adjusted R-squared value of at least 72.8%). To evaluate the performance of the proposed model, the total cost was compared with the case where the decision maker uses a naïve method for the overbooking level. It was found that the total cost from optimal solution is only 0.5 to 1 percent (on average) lower than the cost from regression model, while it is approximately 67% lower than the cost obtained by the naïve method. It indicates that our proposed simplification method using regression analysis can effectively perform in estimating the overbooking level.

Keywords: overbooking, car rental industry, revenue management, stochastic model

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4364 Chronic and Sub-Acute Lumbosacral Radiculopathies Behave Differently to Repeated Back Extension Exercises

Authors: Sami Alabdulwahab

Abstract:

Background: Repeated back extension exercises (RBEEs) are among the management options for symptoms associated with lumbosacral radiculopathy (LSR). RBEEs have been reported to cause changes in the distribution and intensity of radicular symptoms caused by possible compression/decompression of the compromised nerve root. Purpose: The purpose of this study was to investigate the effects of the RBEEs on the neurophysiology of the compromised nerve root and on standing mobility and pain intensity in patients with sub-acute and chronic LSR. Methods: A total of 40 patients with unilateral sub-acute/chronic lumbosacral radiculopathy voluntarily participated in the study; the patients performed 3 sets of 10 RBEEs in the prone position with 1 min of rest between the sets. The soleus H-reflex, standing mobility and pain intensity were recorded before and after the RBEEs. Results: The results of the study showed that the RBEEs significantly improved the H-reflex, standing mobility and pain intensity in patients with sub-acute LSR (p<0.01); there was not a significant improvement in the patients with chronic LSR (p<0.61). Conclusion: RBEEs in prone position is recommended for improving the neurophysiological function of the compromised nerve root and standing mobility in patients with sub-acute LSR. Implication: Sub-acute and chronic LSR responded differently to RBEEs. Sub-acute LSR appear to have flexible and movable disc structures, which could be managed with RBEEs.

Keywords: h-reflex, back extension, lumbosacral radiculopathy, pain

Procedia PDF Downloads 478
4363 Corrosivity of Smoke Generated by Polyvinyl Chloride and Polypropylene with Different Mixing Ratios towards Carbon Steel

Authors: Xufei Liu, Shouxiang Lu, Kim Meow Liew

Abstract:

Because a relatively small fire could potentially cause damage by smoke corrosion far exceed thermal fire damage, it has been realized that the corrosion of metal exposed to smoke atmospheres is a significant fire hazard, except for toxicity or evacuation considerations. For the burning materials in an actual fire may often be the mixture of combustible matters, a quantitative study on the corrosivity of smoke produced by the combustion of mixture is more conducive to the application of the basic theory to the actual engineering. In this paper, carbon steel samples were exposed to smoke generated by polyvinyl chloride and polypropylene, two common combustibles in industrial plants, with different mixing ratios in high humidity for 120 hours. The separate and combined corrosive effects of smoke were examined subsequently by weight loss measurement, scanning electron microscope, energy dispersive spectroscopy and X-ray diffraction. It was found that, although the corrosivity of smoke from polypropylene was much smaller than that of smoke from polyvinyl chloride, smoke from polypropylene enhanced the major corrosive effect of smoke from polyvinyl chloride to carbon steel. Furthermore, the corrosion kinetics of carbon steel under smoke were found to obey the power function. Possible corrosion mechanisms were also proposed. All the analysis helps to provide basic information for the determination of smoke damage and timely rescue after fire.

Keywords: corrosion kinetics, corrosion mechanism, mixed combustible, SEM/EDS, smoke corrosivity, XRD

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4362 A Causal Model for Environmental Design of Residential Community for Elderly Well-Being in Thailand

Authors: Porntip Ruengtam

Abstract:

This article is an extension of previous research presenting the relevant factors related to environmental perceptions, residential community, and the design of a healing environment, which have effects on the well-being and requirements of Thai elderly. Research methodology began with observations and interviews in three case studies in terms of the management processes and environment design of similar existing projects in Thailand. The interview results were taken to summarize with related theories and literature. A questionnaire survey was designed for data collection to confirm the factors of requirements in a residential community intended for the Thai elderly. A structural equation model (SEM) was formulated to explain the cause-effect factors for the requirements of a residential community for Thai elderly. The research revealed that the requirements of a residential community for Thai elderly were classified into three groups when utilizing a technique for exploratory factor analysis. The factors were comprised of (1) requirements for general facilities and activities, (2) requirements for facilities related to health and security, and (3) requirements for facilities related to physical exercise in the residential community. The results from the SEM showed the background of elderly people had a direct effect on their requirements for a residential community from various aspects. The results should lead to the formulation of policies for design and management of residential communities for the elderly in order to enhance quality of life as well as both the physical and mental health of the Thai elderly.

Keywords: elderly, environmental design, residential community, structural equation modeling

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4361 Terrorism and Sustainable Tourism Development

Authors: P. Okoro Ugo Chigozie, P. A. Igbojekwe, E. N. Ukabuilu

Abstract:

Tourism and terrorism experiences are best viewed as dynamic, complex systems with extreme diverse consequences on any nation’s economy. Tourism is one of the biggest industries in the world and one of the economical sectors which grows rapidly; tourism has positive impact on the nation’s economy. Terrorism is the method or the theory behind the method whereby an organized group or party seeks to achieve its avowed aims chiefly through the systematic use of violence; the consequences of terrorism on tourist destinations are inescapable and can be profound. Especially, it threatens the attractiveness of a tourist destination and strips the competitiveness of that destination. Destination’s vulnerability to politically motivated violence not only retracts tourists, but threatens sustainable tourism development. This paper examines the activities of the Jamaata Ahlis Sunna Liddaawati -an Islamic sect popularly known as Boko Haram – and its impact on sustainable tourism development in the Nigeria state. Possible triggers of this insurgency and potentially evolving measure against its influence on sustainable tourism including, strong image management of the tourism industry, feasible tourist safety policy, viable anti-terrorism measures, proactive respond to the challenge of terrorism, reinforcement of the legitimate frameworks and irrevocable penalty against menace of corruption; are discussed in this paper, as limiting the effects of insurgency on the attractiveness of Nigeria as safe tourists destination.

Keywords: Nigeria, terrorism, sustainable tourism development, corruption and competitiveness

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4360 Forms of Social Provision for Housing Investments in Local Planning Acts for European Capitals: Comparative Study and Spatial References

Authors: Agata Twardoch

Abstract:

The processes of commodification of real estate and changes in housing markets have led to a situation where the prices of free market housing in European capitals are significantly higher than the purchasing value of average wages. This phenomenon has many negative social and spatial consequences. At the same time, the attractiveness of real estate as an asset makes these processes progress. Out of concern for sustainable social development, city authorities apply solutions to balance the burdensome effects of codification of housing. One of them is a social provision for housing investments. The article presents a comparative study of solutions applied in selected European capitals, on the example of Warsaw, Paris, London, Berlin, Copenhagen, and Vienna. The study was conducted along with works on expert report for the master plan for Warsaw. The forms of commissions applied in Local Planning Acts were compared, with particular reference to spatial solutions. The results of the analysis made it possible to determine common features of the solutions applied and to establish recommendations for further practice. Major findings of the study indicate that requirement of social provision is achievable in spatial planning documents. Study shows that application of social provision in private housing investments is a useful tool in housing policy against commodification.

Keywords: affordable housing, housing provision, spatial planning, sustainable social development

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4359 Effect of Probiotics and Vitamin B on Plasma Interferon-Gamma and Interleukin-6 Levels in Active Pulmonary Tuberculosis

Authors: Yulistiani Yulistiani, Zamrotul Izzah, Lintang Bismantara, Wenny Putri Nilamsari, Arif Bachtiar, Budi Suprapti

Abstract:

Interferon-gamma (IFN-γ) and interleukin-6 (IL-6) are pro-inflammatory cytokines, which have the protective immune response against Tuberculosis (TB). Indeed, pro-inflammatory cytokines Mycobacterium tuberculosis antigen-specific CD4+ and CD8+ T cells and NK cells increase the level of production of IFN-γ, a cytokine critical for augmenting the microbicidal activity of phagocytes. On the other hand, M. tuberculosis reduces the effects of IFN-γ by inhibiting the transcription of IFN-γ- responsive genes and by inducing the secretion of IL-6, which inhibits IFN-γ signaling. Probiotics Lactobacillus sp. and Bifidobacterium sp. were known to increase IFN-γ production in vivo, while vitamin B1, B6, and B12 worked on macrophages and releasing cytokines. Therefore, the present study was to evaluate the effect of probiotics and vitamin B supplement on changes of plasma cytokine levels in active pulmonary TB. From October to November 2016, twelve M. tuberculosis-infected patients starting anti-TB drugs were recruited, then divided into two groups. Seven patients were given a combination of probiotics and vitamin B, while five patients were in the control group. Plasma IFN-γ and IL-6 levels were measured by the ELISA kit before and a month after treatment. IFN-γ levels raised in four patients receiving the supplement (P = 0.743), while IL-6 increased in three patients in this group until day 30 of treatment (P = 0.298). Taken together, these results show the promising effect of probiotics and vitamin B on stimulation of IFN-γ and IL-6 production during intensive therapy of TB.

Keywords: interferon-gamma, interleukin-6, probiotic, tuberculosis

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4358 China’s Scientific Research of the Arctic (Historical Aspect)

Authors: Cui Long (Allen)

Abstract:

China's attention to the Arctic began in 1925, when the country joined the Svalbard Treaty. China's participation in Arctic exploration was determined by the second and third articles of the treaty, according to which the country could conduct scientific activities in the adjacent waters of Svalbard. The first studies of the New China began in the 50s of the twentieth century. The first scientific projects on Arctic exploration began in the 80s of the twentieth century. During these years, the "National Committee of the People's Republic of China for Arctic Expeditions" and the "Institute of Polar Research" in Shanghai were established. The beginning of Deng Xiaoping's policy of openness and reform has opened a new page in China's scientific research of the Arctic. Since the 90s, the first Chinese scientific programs have been developed with foreign partners. The Chinese Academy of Sciences and its subordinate scientific institutions are actively involved in scientific activities: the Institute of Aerophysics, the Institute of Geographical Sciences and Natural Resources, the Institute of Oceanology, etc. An important event for the development of scientific research in the Arctic was China's entry into the Arctic Council in 2013 as an observer. By 2018, China had conducted nine Arctic expeditions, their purpose was to study the melting of ice and its effects on the world's climate system, as well as the impact of the Arctic climate on China and the presence of plastic waste in the Arctic was monitored. At the beginning of the new millennium, China considers the Arctic as the most important region of a geopolitical and geostrategic nature, for its further logistical and economic development.

Keywords: Arctic, China, history of Arctic research, arctic science, Chinese scientific research in the Arctic, scientific expeditions

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4357 Mobile Health Apps Can Cause More Harm Due to Health Anxiety Than Good

Authors: Malik Takreem Ahmad, Pablo Lamata, Rasi Mizori

Abstract:

Background: In recent years, mobile health apps have grown in popularity as a means for people to track and manage their health. While there is increasing worry that these applications may potentially contribute to the emergence of health anxiety, they can also help to encourage healthy behaviours and provide access to health information. Objective: The objective of this literature review is to look at available mhealth apps and critically evaluate the compromise between reassurance and anxiety. Methodology: A literature review was carried out to analyse the effects of mhealth apps on the creation of health anxiety within the general population. PubMed and SCOPUS were used to search for relevant articles, and abstracts were screened using inclusion criteria of the terms: mhealth apps; e-Health; healthcare apps; cyberchondria; Health anxiety; illness anxiety disorder. A total of 27 studies were included in the review. Results and discussion: The findings suggest a direct relationship between mobile health app use and health anxiety. The impact of mobile health apps on health anxiety may depend on how they are used - individuals receiving a constant stream of health-related information may trigger unnecessary concern about one's health. The need for more regulation and oversight is identified, which can lead to app quality and safety consistency. There are also concerns about data security and privacy and the resulting "digital gap" for individuals without mobiles or internet access. Conclusion: While health apps can be valuable tools for managing and tracking health, individuals need to use them in a balanced and informed way to avoid increased anxiety.

Keywords: mobile health, mhealth apps, cyberchondria, health anxiety

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4356 Excessive Recruitment of Neutrophils and Elastase Release in Emphysema and COPD; Effect of Natural Protease Inhibitors

Authors: Rachid Kacem

Abstract:

Excessive recruitment of Neutrophils into the lungs is a hallmark of several chronic inflammatory disorders such as emphysema and COPD. The resulting of this recruitment is the pathogenesis of lungs which is characterized by an imbalance between leukocyte serine proteinases mainly neutrophil elastase and the physiological inhibitors. The development of emphysema and remodeling of airway tissue occurred when neutrophil migrate into the lungs with more release of elastase and other proteolytic enzymes. Many reports have demonstrated that the extracts from medicinal plants such as Nigella sativa (L.) seeds extracts have anti-elastase activity; this is mainly due to the enrichment of the extracts with many bioactive molecules mainly phenolic compounds. Neutrophil serine proteases including human neutrophil elastase are involved in many inflammatory diseases, such as chronic obstructive pulmonary disease and emphysema. Since the current therapies for these diseases are inadequate and have numerous adverse effects, there is an acute need of potential alternative therapies. The natural protease inhibitors have received increasing attention as useful tools for potential utilization in pharmacology. This work is elucidating the most important natural phenolic substances that have been reported recently for their effectiveness as natural anti-elastase molecules, and hence, to the possibility of their use in the field of pharmaceuticals.

Keywords: medicinal plants, phenols, elastase, anti-elastase, chronic obstructive pulmonary disease, COPD, emphysema

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4355 Dynamics of Soil Carbon and Nitrogen Contents and Stocks along a Salinity Gradient

Authors: Qingqing Zhao, Junhong Bai

Abstract:

To investigate the effects of salinity on dynamics of soil carbon and nitrogen contents and stocks, soil samples were collected at a depth of 30 cm at four sampling sites (Sites B, T, S and P) along a salinity gradient in a drained coastal wetland, the Yellow River Delta, China. The salinity of these four sites ranked in the order: B (8.68±4.25 ms/cm) > T (5.89±3.17 ms/cm) > S (3.19±1.01 ms/cm) > P (2.26±0.39 ms/cm). Soil total carbon (TC), soil organic carbon (SOC), soil microbial biomass carbon (MBC), soil total nitrogen (TC) and soil microbial biomass carbon (MBC) were measured. Based on these data, soil organic carbon density (SOCD), soil microbial biomass carbon density (MBCD), soil nitrogen density (TCD) and soil microbial biomass nitrogen density (MBND) were calculated at four sites. The results showed that the mean concentrations of TC, SOC, MBC, TN and MBN showed a general deceasing tendency with increasing salinities in the top 30 cm of soils. The values of SOCD, MBCD, TND and MBND exhibited similar tendency along the salinity gradient. As for profile distribution pattern, The C/N ratios ranged from 8.28 to 56. 51. Higher C/N ratios were found in samples with high salinity. Correlation analysis showed that the concentrations of TC, SOC and MBC at four sampling sites were significantly negatively correlated with salinity (P < 0.01 or P < 0.05), indicating that salinity could inhibit soil carbon accumulation. However, no significant relationship was observed between TN, MBN and salinity (P > 0.05).

Keywords: carbon content and stock, nitrogen content and stock, salinity, coastal wetland

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4354 The Effects of Inulin on the Stabilization and Stevioside as Sugar-Replacer of Sourcherry Juice-Milk Mixture

Authors: S. Teimouri, S. Abbasi

Abstract:

Milk-fruit juice mixture is a type of soft drinks, which can be produced by mixing milk with pieces of fruits, fruit juices, or fruit juices concentrates. The major problem of these products, mainly the acidic ones, is phase separation which occurs during formulation and storage due to the aggregation of caseins at low pH Short-chain inulin (CLR), long-chain inulin (TEX), native inulin (IQ) and Long-chain inulin (TEX) and short-chain inulin (CLR) combined in different proportions (2o:80, 50:50, and 80:20) were added (2-10 %) to sourcherry juice-milk mixture and their stabilization mechanisms were studied with using rheological and microstructural observations. Stevioside as a bio-sweetener and sugar-replacer was added at last step. Finally, sensory analyses were taken place on stabilized samples. According to the findings, TEX stabilized the mixture at concentration of 8%. MIX and IQ reduced phase separation at high concentration but had not complete effect on stabilization. CLR did not effect on stabilization. Rheological changes and inulin aggregates formation were not observed in CLR samples during the one month storage period. However TEX, MIX and IQ samples formed inulin aggregates and became more thixotropic, elastic and increased the viscosity of mixture. The rate of the inulin aggregates formation and viscosity increasing was in the following order TEX > MIX > IQ. Consequently the mixture which stabilized with inulin and sweetened with stevioside had the prebiotic properties which may suggest to diabetic patients and children.

Keywords: prebiotic, inulin, casein, stabilization, stevioside

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4353 Direct and Moderating Effect of Religious Activities, Sustainability and Peer Support on Job Performance

Authors: Fahad Alam

Abstract:

Work stress directly affects job performance, specifically in a worse environment. Consequently, a social provision plays a crucial part for enhancement. Therefore, the current research investigates the direct and moderating effect between religious activities, sustainability and peer support on job performance at hospitals in Khyber PakhtunKhwa (KPK), Pakistan. Both primary and secondary data are collected through 261 questionnaires of medical employees from four district hospitals in Khyber PakhtunKhwa, Pakistan, in 2018. The analysis was carried out by SPSS16 and SMART PLS3, to test the direct effect of religious activities, sustainability and social support on job performance and the effect of moderating variable 'work environment' on job performance. The finding confirmed that direct and moderating variables play a significant positive effect among religious activities, sustainability and peer support on job performance, the variables help to diminish the strain level or the stress level, consequently helps in the job completed. Affirmative social approaches produce desirable effects on job performance. The research revealed that social provisions are significant triggers for superior practices. Moreover, the results are stimulating because some of the past literature revealed an insignificant correlation between social provision and performance. This study found that there is a significant relationship which persuades health care organizations.

Keywords: job performance, peer’s support, religious activities, sustainability, work environment

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