Search results for: control loop
Commenced in January 2007
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Edition: International
Paper Count: 11090

Search results for: control loop

2810 Design and Development of Tandem Dynamometer for Testing and Validation of Motor Performance Parameters

Authors: Vedansh More, Lalatendu Bal, Ronak Panchal, Atharva Kulkarni

Abstract:

The project aims at developing a cost-effective test bench capable of testing and validating the complete powertrain package of an electric vehicle. Emrax 228 high voltage synchronous motor was selected as the prime mover for study. A tandem type dynamometer comprising of two loading methods; inertial, using standard inertia rollers and absorptive, using a separately excited DC generator with resistive coils was developed. The absorptive loading of the prime mover was achieved by implementing a converter circuit through which duty of the input field voltage level was controlled. This control was efficacious in changing the magnetic flux and hence the generated voltage which was ultimately dropped across resistive coils assembled in a load bank with all parallel configuration. The prime mover and loading elements were connected via a chain drive with a 2:1 reduction ratio which allows flexibility in placement of components and a relaxed rating of the DC generator. The development will aid in determination of essential characteristics like torque-RPM, power-RPM, torque factor, RPM factor, heat loads of devices and battery pack state of charge efficiency but also provides a significant financial advantage over existing versions of dynamometers with its cost-effective solution.

Keywords: absorptive load, chain drive, chordal action, DC generator, dynamometer, electric vehicle, inertia rollers, load bank, powertrain, pulse width modulation, reduction ratio, road load, testbench

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2809 Relationship Between Upper Extremity Erectile Abnormalities with Quality of Life Factors and Physical Self-concept in Boy Students 7 to 10 Years

Authors: Nadiya Zahra Karimi, Amir Ghiami Rad

Abstract:

The physical health of students from an early age and the proper formation of the musculoskeletal system of their body is part of the overall health of these people. Most chronic musculoskeletal problems and pains can be controlled and reduced with education at an early age. Therefore, with the correct and timely diagnosis of these abnormalities, we can play an important role in their proper treatment and control, and in a way, raise the level of quality of life and positive self-concept in students. The aim of this study was to investigate the relationship between erectile dysfunctions of the upper limbs (head and neck, shoulder, thoracic and lumbar) and the quality of life and self-concept of male students aged 7 to 10 years. The statical population of the study consists of 227 students of shahadat boys’ primary school in khajeh city. Due to the corona pandemic conditions, the research samples were identified after screening and available according to the entrance criteria of the study. To validate the quality of life, the valid WHOQOL-BREF questionnaire will be used for self-concept variables, Dolatabadi, Fatemeh (2007) questionnaire, and for physical screening, a checkerboard, plumb line, and flexible ruler will be used. There is a negative and significant relationship between the dimensions of upper limb anomalies and quality of life factors, and also there is a negative and significant relationship between the dimensions of upper limb anomalies and self-concept factors. The results showed that there is a negative and significant relationship between head and neck abnormalities with quality of life and self-concept factors, with a significance level of less than 0.05 in male students aged 7 to 10 years.

Keywords: upper limb erectile dysfunction, quality of life, self-concept, erectile abnormalities

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2808 Exploring the Safety of Sodium Glucose Co-Transporter-2 Inhibitors at the Imperial College London Diabetes Centre, UAE

Authors: Raad Nari, Maura Moriaty, Maha T. Barakat

Abstract:

Introduction: Sodium-glucose co-transporter-2 (SGLT2) inhibitors are a new class of oral anti-diabetic drugs with a unique mechanism of action. They are used to improve glycaemic control in adults with type 2 diabetes by enhancing urinary glucose excretion. In the UAE, there has been certainly an increased use of these medications. As with any new medication, there are safety considerations related to their use in patients with type two diabetes. A retrospective study was conducted at the three main centres of the Imperial College London Diabetes Centre. Methodology: All patients in electronic database (Diamond) from October 2014 to October 2017 were included with a minimum of six months usage of sodium glucose co-transporter inhibitors that comprise canagliflozin, dapagliflozin and empagliflozin. There were 15 paired sample biochemical and clinical correlations. The analysis was done at the start of the study, three months and six months apart. SPSS version 24 was used for this study. Conclusion: This study of sodium glucose co-transporter-2 inhibitors used showed significant reductions in weight, glycated haemoglobin A1C, systolic and diastolic blood pressures. As the case with systematic reviews, there were similar changes in liver enzymes, raised total cholesterol, low density lipopoptein and high density lipoprotein. There was slight improvement in estimated glomerular filtration rate too. Our analysis also showed that they increased in the incidence of urinary tract symptoms and incidence of urinary tract infections.

Keywords: SGLT2 inhibitors dapagliflozin empagliflozin canagliflozin, adverse effects, amputation diabetic ketoacidosis DKA, urinary tract infection

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2807 Infrared Lightbox and iPhone App for Improving Detection Limit of Phosphate Detecting Dip Strips

Authors: H. Heidari-Bafroui, B. Ribeiro, A. Charbaji, C. Anagnostopoulos, M. Faghri

Abstract:

In this paper, we report the development of a portable and inexpensive infrared lightbox for improving the detection limits of paper-based phosphate devices. Commercial paper-based devices utilize the molybdenum blue protocol to detect phosphate in the environment. Although these devices are easy to use and have a long shelf life, their main deficiency is their low sensitivity based on the qualitative results obtained via a color chart. To improve the results, we constructed a compact infrared lightbox that communicates wirelessly with a smartphone. The system measures the absorbance of radiation for the molybdenum blue reaction in the infrared region of the spectrum. It consists of a lightbox illuminated by four infrared light-emitting diodes, an infrared digital camera, a Raspberry Pi microcontroller, a mini-router, and an iPhone to control the microcontroller. An iPhone application was also developed to analyze images captured by the infrared camera in order to quantify phosphate concentrations. Additionally, the app connects to an online data center to present a highly scalable worldwide system for tracking and analyzing field measurements. In this study, the detection limits for two popular commercial devices were improved by a factor of 4 for the Quantofix devices (from 1.3 ppm using visible light to 300 ppb using infrared illumination) and a factor of 6 for the Indigo units (from 9.2 ppm to 1.4 ppm) with repeatability of less than or equal to 1.2% relative standard deviation (RSD). The system also provides more granular concentration information compared to the discrete color chart used by commercial devices and it can be easily adapted for use in other applications.

Keywords: infrared lightbox, paper-based device, phosphate detection, smartphone colorimetric analyzer

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2806 Molecular Diagnosis of Influenza Strains Was Carried Out on Patients of the Social Security Clinic in Karaj Using the RT-PCR Technique

Authors: A. Ferasat, S. Rostampour Yasouri

Abstract:

Seasonal flu is a highly contagious infection caused by influenza viruses. These viruses undergo genetic changes that result in new epidemics across the globe. Medical attention is crucial in severe cases, particularly for the elderly, frail, and those with chronic illnesses, as their immune systems are often weaker. The purpose of this study was to detect new subtypes of the influenza A virus rapidly using a specific RT-PCR method based on the HA gene (hemagglutinin). In the winter and spring of 2022_2023, 120 embryonated egg samples were cultured, suspected of seasonal influenza. RNA synthesis, followed by cDNA synthesis, was performed. Finally, the PCR technique was applied using a pair of specific primers designed based on the HA gene. The PCR product was identified after purification, and the nucleotide sequence of purified PCR products was compared with the sequences in the gene bank. The results showed a high similarity between the sequence of the positive samples isolated from the patients and the sequence of the new strains isolated in recent years. This RT-PCR technique is entirely specific in this study, enabling the detection and multiplication of influenza and its subspecies from clinical samples. The RT-PCR technique based on the HA gene, along with sequencing, is a fast, specific, and sensitive diagnostic method for those infected with influenza viruses and its new subtypes. Rapid molecular diagnosis of influenza is essential for suspected people to control and prevent the spread of the disease to others. It also prevents the occurrence of secondary (sometimes fatal) pneumonia that results from influenza and pathogenic bacteria. The critical role of rapid diagnosis of new strains of influenza is to prepare a drug vaccine against the latest viruses that did not exist in the community last year and are entirely new viruses.

Keywords: influenza, molecular diagnosis, patients, RT-PCR technique

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2805 Weak Electric Fields Enhance Growth and Nutritional Quality of Kale

Authors: So-Ra Lee, Myung-Min Oh

Abstract:

Generally, plants growing on the earth are under the influence of natural electric fields and may even require exposure of the electric field to survive. Electric signals have been observed within plants and seem to play an important role on various metabolic processes, but their role is not fully understood. In this study, we attempted to explore the response of plants under external electric fields in kale (Brassica oleracea var. acephala). The plants were hydroponically grown for 28 days in a plant factory. Electric currents at 10, 50 and 100 mA were supplied to nutrient solution for 3 weeks. Additionally, some of the plants were cultivated in a Faraday cage to remove the natural electric field. Kale plants exposed to electric fields had higher fresh weight than the control and plants in Faraday cage. Absence of electric field caused a significant decrease in shoot dry weight and root growth. Leaf area also showed a similar response with shoot fresh weight. Supplying weak electric stimulation enhanced nutritional quality including total phenolic content and antioxidant capacity. This work provides basic information on the effects of electric fields on plants and is a meaningful attempt for developing a new economical technology to increase crop productivity and quality by applying an electric field. This work was supported by Korea Institute of Planning and Evaluation for Technology in Food, Agriculture, Forestry and Fisheries (IPET) through Agriculture, Food and Rural Affairs Research Center Support Program, funded by Ministry of Agriculture, Food and Rural Affairs (MAFRA) (717001-07-02-HD240).

Keywords: electroculture, electric signal, faraday cage, electric field

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2804 Serum Potassium Before, During and After Exercise at 70% Maximal Heart Rate: The Safe Exercise Dosage Across Different Parameters of Health and Fitness Level

Authors: Omar bin Mihat

Abstract:

The number of sudden deaths is increasing over the past years. These deaths occur not during physical activities but upon cessation. Post-mortem confirms these deaths as cardiac arrest non-specifically. Congenital heart disease is a condition undiagnosed whereby only surface upon physical exertion leading to sudden death is unavoidable. Channelopathy, a condition that refers to any disease from the defect in iron-channel function, particularly the sodium-potassium pump, during the cessation of the exercise can be controlled. The derivation of heart rate return (HRrtn) is a procedure of a control cooling down process according to the heart rate (HR). Empirically, potassium rises linearly with intensity and falls sharply upon abrupt cessation of exertion, resulting in fatal arrhythmia due to hypokalaemia. It is vital that the flux of potassium should be maintained within the normal range during physical activities. To achieve this, the dosage of physical exertion (exercise) should be identified. Various percentages of the intensity of maximum heart rate (MHR) will precipitate different adaptations and remodeling of various organs. 70% of MHR will surface physiological adaptations, including enhancement of endurance, fitness level, and general health, and there was no significant rise of serum potassium (K+) during the entire phase of the treadmill brisk walk at a different rate of perceived exertion (RPE) from the subject of various fitness background. There was also no significant rise in blood pressure (BP) during the entire phase of the treadmill brisk walk, substantiating 70% MHR is the safe dosage across different parameters of health and fitness level.

Keywords: potassium, maximal heart rate, exercise dosage, fitness level

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2803 Investigating the Characteristics of Multi-Plastic Composites Prepared from a Mixture of Silk Fibers and Recycled Polycarbonate

Authors: Razieh Shamsi, Mehdi Faezipour, Ali Abdolkhani

Abstract:

In this research, the characteristics of composites prepared from waste silk fibers and recycled polycarbonate polymer (used compacted boards) at four levels of 0, 10, 20, and 30% (silk fibers) and using 2% N- 2-Aminoethyl-3-Aminopropyltrimethoxysilane was investigated as a coupling agent and melt process method. Silk fibers (carpet weaving waste) with dimensions of 8-18 mm were prepared, and recycled polymer with 9 mesh grading was ground. Production boards in 3 thicknesses, 3 mm (tensile test samples), 5 mm (bending test samples, water absorption, and thickness shrinkage), 7 mm (impact resistance test samples) ) with a specific weight of 1 gram per cubic centimeter, hot pressing time and temperature of 12 minutes and 190 degrees Celsius with a pressure of 130 bar, cold pressing time of 6 minutes with a pressure of 50 bar and using the coupling agent N- (2- Aminoethyl)-3-aminopropyltrimethoxysilane was prepared in a constant amount of 2% of the dry weight of the filler. The results showed that, in general, by adding silk fibers to the base polymer, compared to the control samples (pure recycled polycarbonate polymer) and also by increasing the amount of silk fibers, almost all the resistances increased. The amount of water absorption of the constructed composite increased with the increase in the amount of silk fibers, and the thickness absorption was equal to 0% even after 72 hours of immersion in water. The thermal resistance of the pure recycled polymer was higher than the prepared composites, and by adding silk fibers to the base polymer and also by increasing the amount of silk fibers from 10 to 30%, the thermal resistance of the composites decreased.

Keywords: wood composite, recycled polycarbonate, silk fibers, polymer

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2802 The Differences and the Similarities between Corporate Governance Principles in Islamic Banks and Conventional Banks

Authors: Osama Shibani

Abstract:

Corporate governance effective is critical to the proper functioning of the banking sector and the economy as a whole, the Basel Committee have issued principles of corporate governance inspired from Organisation for Economic Co-operation and Development (OECD), but there is no single model of corporate governance that can work well in every country; each country, or even each organization should develop its own model that can cater for its specific needs and objectives, the corporate governance in Islamic Institutions is unique and offers a particular structure and guided by a control body which is Shariah supervisory Board (SSB), for this reason Islamic Financial Services Board in Malaysia (IFSB) has amended BCBS corporate governance principles commensurate with Islamic financial Institutions to suit the nature of the work of Islamic institutions, this paper highlight these amended by using comparative analysis method in context of the differences of corporate governance structure of Islamic banks and conventional banks. We find few different between principles (Principle 1: The Board's overall responsibilities, Principles 3: Board’s own structure and practices, Principles 9: Compliance, Principle 10: Internal audit, Principle 12: Disclosure and transparency) and there are similarities between principles (Principle 2: Board qualifications and composition, Principles 4: Senior Management (composition and tasks), Principle 6: Risk Management and Principle 8: Risk communication). Finally, we found that corporate governance principles issued by Islamic Financial Services Board (IFSB) are complemented to CG principles of Basel Committee on Banking Supervision (BCBS) with some modifications to suit the composition of Islamic banks, there are deficiencies in the interest of the Basel Committee to Islamic banks.

Keywords: basel committee (BCBS), corporate governance principles, Islamic financial services board (IFSB), agency theory

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2801 Geophysical Methods of Mapping Groundwater Aquifer System: Perspectives and Inferences From Lisana Area, Western Margin of the Central Main Ethiopian Rift

Authors: Esubalew Yehualaw Melaku, Tigistu Haile Eritro

Abstract:

In this study, two basic geophysical methods are applied for mapping the groundwater aquifer system in the Lisana area along the Guder River, northeast of Hosanna town, near the western margin of the Central Main Ethiopian Rift. The main target of the study is to map the potential aquifer zone and investigate the groundwater potential for current and future development of the resource in the Gode area. The geophysical methods employed in this study include, Vertical Electrical Sounding (VES) and magnetic survey techniques. Electrical sounding was used to examine and map the depth to the potential aquifer zone of the groundwater and its distribution over the area. On the other hand, a magnetic survey was used to delineate contact between lithologic units and geological structures. The 2D magnetic modeling and the geoelectric sections are used for the identification of weak zones, which control the groundwater flow and storage system. The geophysical survey comprises of twelve VES readings collected by using a Schlumberger array along six profile lines and more than four hundred (400) magnetic readings at about 10m station intervals along four profiles and 20m along three random profiles. The study result revealed that the potential aquifer in the area is obtained at a depth range from 45m to 92m. This is the response of the highly weathered/ fractured ignimbrite and pumice layer with sandy soil, which is the main water-bearing horizon. Overall, in the neighborhood of four VES points, VES- 2, VES- 3, VES-10, and VES-11, shows good water-bearing zones in the study area.

Keywords: vertical electrical sounding, magnetic survey, aquifer, groundwater potential

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2800 The Effects of L-Arginine Supplementation on Clinical Symptoms, Quality of Life, and Anal Internal Sphincter Pressure in Patients with Chronic Anal Fissure

Authors: Masoumeh Khailghi Sikaroudi, Mohsen Masoodi, Fazad Shidfar, Meghdad Sedaghat

Abstract:

Background: The hypertonicity of internal anal sphincter resting pressure is one of the main reasons for chronic anal fissures. The aim of this study is to assess the effect of oral administration of L-arginine on anal fissure symptom improvement by relaxation of the internal anal sphincter. Method: Seventy-six chronic anal fissure patients (age: 18-65 years) took part in this randomized, double-blind, placebo-controlled trial study from February 2019 to October 2020 at Rasoul-e-Akram Hospital, Tehran, Iran. Participants were allocated into treatment (L-arginine) or placebo groups. They took a 1000 mg capsule three times a day for one month and were followed up at the end of the first and third months after receiving the intervention. Clinical symptoms, anal sphincter resting pressure, and quality of life (QoL) were completed at baseline and the end of the study. Result: The analysis of data was shown significant improvement in bleeding, fissure size, and pain within each group; however, this effect was more seen in the arginine group compared to the control group at the end of the study (P-values<0.001). Following that, a significant increase in QoL was seen just in patients who were treated with arginine (P-value=0.006). Also, the comparison of anal pressures to baseline and between groups at the end of the study showed a significant reduction in sphincter pressure in treated patients (P-value<0.001, =0.049; respectively). Conclusion: Oral administration of 3000 mg L-arginine can heal chronic anal fissures by reducing anal internal sphincter pressure with fewer side effects. However, a long-term study with more follow-up is recommended.

Keywords: L-arginine, anal fissure, sphincter pressure, clinical symptoms, quality of life

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2799 Sulfamethoxazole Removal and Ammonium Nitrogen Conversion by Microalgae-Bacteria Consortium in Ammonium-Rich Wastewater: Responses Analysis

Authors: Eheneden Iyobosa, Rongchang Wang, Adesina Odunayo Blessing, Gaoxiang Chen, Haijing Ren, Jianfu Zhao

Abstract:

In the treatment of ammonium-rich wastewater with 500 μg/L sulfamethoxazole (SMX) antibiotic by a Microalgae-Bacteria Consortium, diverse parameters were monitored to assess treatment efficacy. Over 14 days, residual SMX concentrations decreased markedly from 500 μg/L to 45.6 μg/L, and removal rates declined from 102.4 to 9.9 μg/L/day. Biomass exhibited consistent growth, reaching a peak of 542.6 mg/L on day 10. Chlorophyll-a, chlorophyll-b, and carotenoid levels varied over time, reflecting fluctuations in microalgal activity. Extracellular polymeric substances (EPS) production showed temporal variations, with protein content ranging from 69.4 to 162.3 mg/g Dry cell weight (DCW) and polysaccharides content from 50.6 to 82.8 mg/g DCW. Ammonium nitrogen concentration decreased steadily from 300 mg/L to 5 mg/L throughout the treatment period. The bacterial community composition was significantly altered in the presence of antibiotics, with notable increases in Bacteroidota and Proteobacteria. Community richness and diversity indices were higher in the antibiotics-treated group than in the control group, as evidenced by the Chao index (258 compared to 181), Shannon index (1.8085 compared to 1.1545), and Simpson index (0.5032 compared to 0.6478), indicating notable shifts in microbial community structure. These findings demonstrate the efficacy of the Microalgae-Bacteria Consortium in removing SMX from wastewater and suggest its potential to mitigate antibiotic pollution while maintaining microbial diversity.

Keywords: ammonium-rich wastewater, microalgae-bacteria consortium, sulfamethoxazole removal, microbial community diversity, biomass growth

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2798 Device-integrated Micro-thermocouples for Reliable Temperature Measurement of GaN HEMTs

Authors: Hassan Irshad Bhatti, Saravanan Yuvaraja, Xiaohang Li

Abstract:

GaN-based devices, such as high electron mobility transistors (HEMTs), offer superior characteristics for high-power, high-frequency, and high-temperature applications [1]. However, this exceptional electrical performance is compromised by undesirable self-heating effects under high-power applications [2, 3]. Some of the issues caused by self-heating are current collapse, thermal runway and performance degradation [4, 5]. Therefore, accurate and reliable methods for measuring the temperature of individual devices on a chip are needed to monitor and control the thermal behavior of GaN-based devices [6]. Temperature measurement at the micro/nanoscale is a challenging task that requires specialized techniques such as Infrared microscopy, Raman thermometry, and thermoreflectance. Recently, micro-thermocouples (MTCs) have attracted considerable attention due to their advantages of simplicity, low cost, high sensitivity, and compatibility with standard fabrication processes [7, 8]. A micro-thermocouple is a junction of two different metal thin films, which generates a Seebeck voltage related to the temperature difference between a hot and cold zone. Integrating MTC in a device allows local temperature to be measured with high sensitivity and accuracy [9]. This work involves the fabrication and integration of micro-thermocouples (MTCs) to measure the channel temperature of GaN HEMT. Our fabricated MTC (Platinum-Chromium junction) has shown a sensitivity of 16.98 µV/K and can measure device channel temperature with high precision and accuracy. The temperature information obtained using this sensor can help improve GaN-based devices and provide thermal engineers with useful insights for optimizing their designs.

Keywords: Electrical Engineering, Thermal engineering, Power Devices, Semiconuctors

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2797 Optimal Parameters of Two-Color Ionizing Laser Pulses for Terahertz Generation

Authors: I. D. Laryushin, V. A. Kostin, A. A. Silaev, N. V. Vvedenskii

Abstract:

Generation of broadband intense terahertz (THz) radiation attracts reasonable interest due to various applications, such as the THz time-domain spectroscopy, the probing and control of various ultrafast processes, the THz imaging with subwavelength resolution, and many others. One of the most promising methods for generating powerful and broadband terahertz pulses is based on focusing two-color femtosecond ionizing laser pulses in gases, including ambient air. For this method, the amplitudes of terahertz pulses are determined by the free-electron current density remaining in a formed plasma after the passage of the laser pulse. The excitation of this residual current density can be treated as multi-wave mixing: Аn effective generation of terahertz radiation is possible only when the frequency ratio of one-color components in the two-color pulse is close to irreducible rational fraction a/b with small odd sum a + b. This work focuses on the optimal parameters (polarizations and intensities) of laser components for the strongest THz generation. The optimal values of parameters are found numerically and analytically with the use of semiclassical approach for calculating the residual current density. For frequency ratios close to a/(a ± 1) with natural a, the strongest THz generation is shown to take place when the both laser components have circular polarizations and equal intensities. For this optimal case, an analytical formula for the residual current density was derived. For the frequency ratios such as 2/5, the two-color ionizing pulses with circularly polarized components practically do not excite the residual current density. However, the optimal parameters correspond generally to specific elliptical (not linear) polarizations of the components and intensity ratios close to unity.

Keywords: broadband terahertz radiation, ionization, laser plasma, ultrashort two-color pulses

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2796 Maternal and Neonatal Outcomes in Women Undergoing Bariatric Surgery: A Systematic Review and Meta-Analysis

Authors: Nicolas Galazis, Nikolina Docheva, Constantinos Simillis, Kypros Nicolaides

Abstract:

Background: Obese women are at increased risk for many pregnancy complications, and bariatric surgery (BS) before pregnancy has shown to improve some of these. Objectives: To review the current literature and quantitatively assess the obstetric and neonatal outcomes in pregnant women who have undergone BS. Search Strategy: MEDLINE, EMBASE and Cochrane databases were searched using relevant keywords to identify studies that reported on pregnancy outcomes after BS. Selection Criteria: Pregnancy outcome in firstly, women after BS compared to obese or BMI-matched women with no BS and secondly, women after BS compared to the same or different women before BS. Only observational studies were included. Data Collection and Analysis: Two investigators independently collected data on study characteristics and outcome measures of interest. These were analysed using the random effects model. Heterogeneity was assessed and sensitivity analysis was performed to account for publication bias. Main Results: The entry criteria were fulfilled by 17 non-randomised cohort or case-control studies, including seven with high methodological quality scores. In the BS group, compared to controls, there was a lower incidence of preeclampsia (OR, 0.45, 95% CI, 0.25-0.80; p=0.007), GDM (OR, 0.47, 95% CI, 0.40-0.56; P<0.001) and large neonates (OR 0.46, 95% CI 0.34-0.62; p<0.001) and a higher incidence of small neonates (OR 1.93, 95% CI 1.52-2.44; p<0.001), preterm birth (OR 1.31, 95% CI 1.08-1.58; p=0.006), admission for neonatal intensive care (OR 1.33, 95% CI 1.02-1.72; p=0.03) and maternal anaemia (OR 3.41, 95% CI 1.56-7.44, p=0.002). Conclusions: BS as a whole improves some pregnancy outcomes. Laparoscopic adjustable gastric banding does not appear to increase the rate of small neonates that was seen with other BS procedures. Obese women of childbearing age undergoing BS need to be aware of these outcomes.

Keywords: bariatric surgery, pregnancy, preeclampsia, gestational diabetes, birth weight

Procedia PDF Downloads 407
2795 Growth and Nutrient Utilization of Some Citrus Peels and Vitamin Premix as Additives in Clarias Gariepinus Diets

Authors: Eunice Oluwayemisi Adeparusi, Mary Adedolapo Ijadeyila

Abstract:

The study was carried out at the Federal University of Technology, Akure, Nigeria, West Africa. Seven set of diets were prepared comprising of two sets. The first set consisted of a combination of three diets from a combination of two different citrus peels from Orange (Citrus sinesis), Tangerine (Citrus tangerina / Citrus reticulata) and Tangelo (Citrus tangelo a hybrid of Citrus reticulata and Citrus maxima) at 50:50 while the other three consisted f50:50. Diet with 100% vitamin premix served as the control. Air-dried citrus peels were added in a 40% crude protein diet for the juveniles (4.49±0.05g) Clarias gariepinus. The experiment was carried out for a period of 56 days in triplicate trials. Fish were randomly distributed into twenty-one tanks at ten fish per tanks. The feed was extruded and fed to satiation twice daily. The result shows that fish fed Tangelo and Tangerine (TGL-TGR) had the best growth response in terms of final weight, specific growth rate, feed conversion ratio and feed utilization efficiency when compared with other diets. The FCR of fish in the diet ranges from 0.93-1.62. Fish fed the mixture of Orange peel and Vitamin-mineral premix (ORG-VIT) and those on Tangelo and Vitamin-mineral premix (TGL-VIT) had higher survival rate. There were significant differences (P<0.05) in the mean final weight, weight gain and specific growth rate. The result shows that citrus peels enhance the growth performance and feed utilization of the juvenile of African mud catfish, thereby reducing the cost of fish production.

Keywords: African mud catfish, growth, citrus peels, vitamin-mineral premix, nutrient utilization, additives

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2794 Anthelminthic Effect of Clitoria Ternatea on Paramphistomum Cervi in Buffalo (Bubalus Bubalis) of Udaipur, Rajasthan, India

Authors: Bhanupriya Sanger, Kiran Roat, Gayatri Swarnakar

Abstract:

Helminths including Paramphistomum Cervi (P. cervi) are a major cause of reduced production in livestock or domestic ruminant. Rajasthan is the largest state of India having a maximum number of livestock. The economy of rural people largely depends on livestock such as cow, buffalo, goat and sheep. The prevalence of P. cervi helminth parasite is extremely high in buffalo (Bubalus bubalis) of Udaipur, which causes the disease paramphistomiasis. This disease mainly affects milk, meat, wool production and loss of life of buffalo. Chemotherapy is the only efficient and effective tool to cure and control the helminth P. cervi infection, as efficacious vaccines against helminth have not been developed so far. Various veterinary drugs like Albendazole have been used as the standard drug for eliminating P. cervi from buffalo, but these drugs are unaffordable and inaccessible for poor livestock farmers. The fruits, leaves and seeds of Clitoria ternatea Linn. are known for their ethno-medicinal value and commonly known as “Aprajita” in India. Seed extract of Clitoria ternatea found to have a significant anthelmintic action against Paramphistomum cervi at the dose of 35 mg/ml. The tegument of treated P. cervi was compared with controlled parasites by light microscopy. Treated P. cervi showed extensive distortion and destruction of the tegument including ruptured parenchymal cells, disruption of musculature cells, swelling and vacuolization in tegumental and sub tegumental cells. As a result, it can be concluded that the seeds of Clitoria ternatea can be used as the anthelmintic agent. Key words: Paramphistomiasis, Buffalo, Alcoholic extract, Paramphistomum cervi, Clitoria ternatea.

Keywords: buffalo, Clitoria ternatea, Paramphistomiasis, Paramphistomum cervi

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2793 Improvement of Microscopic Detection of Acid-Fast Bacilli for Tuberculosis by Artificial Intelligence-Assisted Microscopic Platform and Medical Image Recognition System

Authors: Hsiao-Chuan Huang, King-Lung Kuo, Mei-Hsin Lo, Hsiao-Yun Chou, Yusen Lin

Abstract:

The most robust and economical method for laboratory diagnosis of TB is to identify mycobacterial bacilli (AFB) under acid-fast staining despite its disadvantages of low sensitivity and labor-intensive. Though digital pathology becomes popular in medicine, an automated microscopic system for microbiology is still not available. A new AI-assisted automated microscopic system, consisting of a microscopic scanner and recognition program powered by big data and deep learning, may significantly increase the sensitivity of TB smear microscopy. Thus, the objective is to evaluate such an automatic system for the identification of AFB. A total of 5,930 smears was enrolled for this study. An intelligent microscope system (TB-Scan, Wellgen Medical, Taiwan) was used for microscopic image scanning and AFB detection. 272 AFB smears were used for transfer learning to increase the accuracy. Referee medical technicians were used as Gold Standard for result discrepancy. Results showed that, under a total of 1726 AFB smears, the automated system's accuracy, sensitivity and specificity were 95.6% (1,650/1,726), 87.7% (57/65), and 95.9% (1,593/1,661), respectively. Compared to culture, the sensitivity for human technicians was only 33.8% (38/142); however, the automated system can achieve 74.6% (106/142), which is significantly higher than human technicians, and this is the first of such an automated microscope system for TB smear testing in a controlled trial. This automated system could achieve higher TB smear sensitivity and laboratory efficiency and may complement molecular methods (eg. GeneXpert) to reduce the total cost for TB control. Furthermore, such an automated system is capable of remote access by the internet and can be deployed in the area with limited medical resources.

Keywords: TB smears, automated microscope, artificial intelligence, medical imaging

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2792 Portable Palpation Probe for Diabetic Foot Ulceration Monitoring

Authors: Bummo Ahn

Abstract:

Palpation is widely used to measure soft tissue firmness or stiffness in the living condition in order to apply detection, diagnosis, and treatment of tumors, scar tissue, abnormal muscle tone, or muscle spasticity. Since these methods are subjective and depend on the proficiency level, it is concluded that there are other diagnoses depending on the condition of the experts and the results are not objective. The mechanical property obtained by using the elasticity of the tissue is important to calculate a predictive variable for monitoring abnormal tissues. If the mechanical load such as reaction force on the foot increases in the same region under the same conditions, the mechanical property of the tissue is changed. Therefore, objective diagnosis is possible not only for experts but also for patients using this quantitative information. Furthermore, the portable system also allows non-experts to easily diagnose at home, not in hospitals or institutions. In this paper, we introduce a portable palpation system that can be used to measure the mechanical properties of human tissue, which can be applied to monitor diabetic foot ulceration patients with measuring the mechanical property change of foot tissue. The system was designed to be smaller and portable in comparison with the conventional palpation systems. It is consists of the probe, the force sensor, linear actuator, micro control unit, the display module, battery, and housing. Using this system, we performed validation experiments by applying different palpations (3 and 5 mm) to soft tissue (silicone rubber) and measured reaction forces. In addition, we estimated the elastic moduli of the soft tissue against different palpations and compare the estimated elastic moduli that show similar value even if the palpation depths are different.

Keywords: palpation probe, portable, diabetic foot ulceration, monitoring, mechanical property

Procedia PDF Downloads 120
2791 Structural Morphing on High Performance Composite Hydrofoil to Postpone Cavitation

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

Abstract:

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

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

Procedia PDF Downloads 176
2790 A Pilot Epidemiological Survey of Parasitic Problems of Goats in and Around Derawar Fort Area, Cholistan, Pakistan

Authors: Muhammad Tahir Riaz, Khalid Mehmood, Ahmad Waseem Akhtar, Tariq Abbas, Sadaqat Ali, Muhammad Altaf

Abstract:

Livestock sector contributes around 55.9 and 11.8% to agriculture and GDP respectively, according to economic survey of Pakistan 2013-2014. The goats population has been estimated about 66.6 million (M). Parasitic infestation is a major health problem in goats causing loss in body weight, poor body condition, low birth weights, and difficulty in kidding. Keeping in view the utilization of these animals in the country, a pilot epidemiological survey was conducted to find out the major parasitic problems of goats in and around Derawar fort area, Cholistan. Data regarding 662 fecal samples of goats was collected from 25 tobas of Cholistan during June 2012 to June 2013. All the fecal samples were examined through Direct Smear Method and Salt Flotation Technique for the presence of helminth eggs. External parasites were taken from the various components of the carcass of goat and were conserved in 70% alcohol in hygienic, properly enclosed glass jars that were tagged thoroughly. The collected date was analyzed statistically by Chi-square test to find out the prevalence in goats. Out of 662 goats, 261 (39.42%) were found positive for parasites. 233 (35.20%) goats were found positive for gastrointestinal parasites while 28 (4.23%) were positive for external parasites including ticks 20 (3.02%) and mange 8 (1.21%). The higher prevalence of parasites in the study area may be due to pasture grazing, poor management and lack of extension work. In this regards proper management and control measures should be adopted to minimize the Parasitic Problems.

Keywords: Cholistan, goats, parasite, surveillance

Procedia PDF Downloads 566
2789 User Authentication Using Graphical Password with Sound Signature

Authors: Devi Srinivas, K. Sindhuja

Abstract:

This paper presents architecture to improve surveillance applications based on the usage of the service oriented paradigm, with smart phones as user terminals, allowing application dynamic composition and increasing the flexibility of the system. According to the result of moving object detection research on video sequences, the movement of the people is tracked using video surveillance. The moving object is identified using the image subtraction method. The background image is subtracted from the foreground image, from that the moving object is derived. So the Background subtraction algorithm and the threshold value is calculated to find the moving image by using background subtraction algorithm the moving frame is identified. Then, by the threshold value the movement of the frame is identified and tracked. Hence, the movement of the object is identified accurately. This paper deals with low-cost intelligent mobile phone-based wireless video surveillance solution using moving object recognition technology. The proposed solution can be useful in various security systems and environmental surveillance. The fundamental rule of moving object detecting is given in the paper, then, a self-adaptive background representation that can update automatically and timely to adapt to the slow and slight changes of normal surroundings is detailed. While the subtraction of the present captured image and the background reaches a certain threshold, a moving object is measured to be in the current view, and the mobile phone will automatically notify the central control unit or the user through SMS (Short Message System). The main advantage of this system is when an unknown image is captured by the system it will alert the user automatically by sending an SMS to user’s mobile.

Keywords: security, graphical password, persuasive cued click points

Procedia PDF Downloads 537
2788 Fabrication of Uniform Nanofibers Using Gas Dynamic Virtual Nozzle Based Microfluidic Liquid Jet System

Authors: R. Vasireddi, J. Kruse, M. Vakili, M. Trebbin

Abstract:

Here we present a gas dynamic virtual nozzle (GDVN) based microfluidic jetting devices for spinning of nano/microfibers. The device is fabricated by soft lithography techniques and is based on the principle of a GDVN for precise three-dimensional gas focusing of the spinning solution. The nozzle device is used to produce micro/nanofibers of a perfluorinated terpolymer (THV), which were collected on an aluminum substrate for scanning electron microscopy (SEM) analysis. The influences of air pressure, polymer concentration, flow rate and nozzle geometry on the fiber properties were investigated. It was revealed that surface properties are controlled by air pressure and polymer concentration while the diameter and shape of the fibers are influenced mostly by the concentration of the polymer solution and pressure. Alterations of the nozzle geometry had a negligible effect on the fiber properties, however, the jetting stability was affected. Round and flat fibers with differing surface properties from craters, grooves to smooth surfaces could be fabricated by controlling the above-mentioned parameters. Furthermore, the formation of surface roughness was attributed to the fast evaporation rate and velocity (mis)match between the polymer solution jet and the surrounding air stream. The diameter of the fibers could be tuned from ~250 nm to ~15 µm. Because of the simplicity of the setup, the precise control of the fiber properties, access to biocompatible nanofiber fabrication and the easy scale-up of parallel channels for high throughput, this method offers significant benefits compared to existing solution-based fiber production methods.

Keywords: gas dynamic virtual nozzle (GDVN) principle, microfluidic device, spinning, uniform nanofibers

Procedia PDF Downloads 150
2787 Evaluation of Serine and Branched Chain Amino Acid Levels in Depression and the Beneficial Effects of Exercise in Rats

Authors: V. A. Doss, R. Sowndarya, K. Juila Rose Mary

Abstract:

Objective: Amino acid neurotransmitter system dysfunction plays a major role in the pathophysiology of depression. The objective of the present study was to identify the amino acids as possible metabolite biomarkers for depression using GCMS (Gas Chromatography Mass Spectrometry) before and after exercise regimen in brain samples of depression induced animal models. Methods: Depression-like behaviour was induced by Chronic Unpredictable mild stress (CUMS). Severity of depression was measured by forced swim test (FST) and sucrose consumption test (SCT). Swimming protocol was followed for 4 weeks of exercise treatment. Brain obtained from depressed and exercise treated rats were used for the metabolite analysis by GCMS. Subsequent statistical analysis obtained by ANOVA followed by post hoc test revealed significant metabolic changes. Results: Amino acids such as alanine, glycine, serine, glutamate, homocysteine, proline and branched chain aminoacids (BCAs) Leucine, Isoleucine, Valine were determined in brain samples of control, depressed and exercised groups. Among these amino acids, the levels of D-Serine and branched chain amino acids were found to be decreased in depression induced rats. After four weeks of swimming exercise regimen, there were improvements in the levels of serine and Branched chain amino acids. Conclusion: We suggest that Serine and BCAs may be investigated as potential metabolite markers using GCMS and their beneficial metabolic changes in Exercise.

Keywords: metabolomics, depression, forced swim test, exercise, amino acid metabolites, GCMS, biomarker

Procedia PDF Downloads 326
2786 Antiprotozoal Activity against Entamoeba histolytica of Flavonoids Isolated from Lippia graveolens Kunth

Authors: Ramiro Quintanilla-Licea, Isvar K. Angeles-Hernandez, Javier Vargas-Villarreal

Abstract:

Amebiasis caused by Entamoeba histolytica, associated with high morbidity and mortality, is currently a significant public health problem worldwide, especially in developing countries. In the world, around 50 million people develop this illness, and up to 100,000 deaths occur annually. Due to the side-effects and the resistance that pathogenic protozoa show against common antiparasitic drugs (e.g., metronidazole), growing attention has been paid to plants used in traditional medicine around the world to find new antiprotozoal agents. In this study is reported about the isolation and structure elucidation of antiamoebic compounds occurring in Lippia graveolens Kunth (Mexican oregano). The work-up of the methanol extract of L. graveolens afforded the known flavonoids pinocembrin (1), sakuranetin (2), cirsimaritin (3) and naringenin (4) by bioguided isolation using several chromatographic techniques. Structural elucidation of the isolated compounds was based on spectroscopic/spectrometric analyses (IR; 1H- and 13C-NMR; MS) and comparison with literature data. These compounds showed significant antiprotozoal activity against Entamoeba histolytica trophozoites using in vitro tests (positive control metronidazole IC50 0.205 µg/mL). The antiprotozoal activity of pinocembrin and naringenin (IC50 of 29.51 µg/mL and 28.85 µg/mL, respectively) was higher compared with sakuranetin (44.47 µg/mL) and with cirsimaritin (150.00 µg/mL), revealing that a 5,7-dihydroxylated A ring is essential for antiprotozoal activity. These research funds may validate the use of this plant in the traditional Mexican medicine for the treatment of some digestive disorders and can help to integrate the use of extracts of L. graveolens in the conventional and complementary medicine for the treatment of parasitic diseases.

Keywords: amoebiasis, antiprotozoal agents, bioguided isolation, infectious diseases

Procedia PDF Downloads 189
2785 Prevalence and Associated Factors of Periodontal Disease among Diabetes Patients in Addis Ababa, Ethiopia, 2018

Authors: Addisu Tadesse Sahile, Tennyson Mgutshini

Abstract:

Background: Periodontal disease is a common, complex, inflammatory disease characterized by the destruction of tooth-supporting soft and hard tissues of the periodontium and a major public health problem across developed and developing countries. Objectives: The study was aimed at assessing the prevalence of periodontal disease and associated factors among diabetes patients in Addis Ababa, Ethiopia, 2018. Methods: Institutional based cross-sectional study was conducted on 388 diabetes patients selected by systematic random sampling method from March to May 2018. The study was conducted at two conveniently selected public hospitals in Addis Ababa. Data were collected with pre-tested, structured and translated questionnaire then entered to SPSS version 23 software for analysis. Descriptive statistics as a summary, in line with chi-square and binary logistics regression to identify factors associated with periodontal disease, were applied. A 95% CI with a p-value less than 5% was used as a level of significance. Results: Ninety-one percent (n=353) of participants had periodontal disease while oral examination was done in six regions. While only 9% (n=35) of participants were free of periodontal disease. The number of tooth brushings per day, correct techniques of brushing, malocclusion, and fillings that are defective were associated with periodontal disease at p < 0.05. Conclusion and recommendation: A higher prevalence of periodontal disease among diabetes patient was observed. The frequency of tooth brushing, correct techniques of brushing, malocclusion and defective fillings were associated with periodontal disease. Emphasis has to be given to oral health of diabetes patients by every concerned body so as to control the current higher burden of periodontal disease in diabetes.

Keywords: periodontal disease, risk factors, diabetes mellitus, Addis Ababa

Procedia PDF Downloads 128
2784 Numerical Simulation of Footing on Reinforced Loose Sand

Authors: M. L. Burnwal, P. Raychowdhury

Abstract:

Earthquake leads to adverse effects on buildings resting on soft soils. Mitigating the response of shallow foundations on soft soil with different methods reduces settlement and provides foundation stability. Few methods such as the rocking foundation (used in Performance-based design), deep foundation, prefabricated drain, grouting, and Vibro-compaction are used to control the pore pressure and enhance the strength of the loose soils. One of the problems with these methods is that the settlement is uncontrollable, leading to differential settlement of the footings, further leading to the collapse of buildings. The present study investigates the utility of geosynthetics as a potential improvement of the subsoil to reduce the earthquake-induced settlement of structures. A steel moment-resisting frame building resting on loose liquefiable dry soil, subjected to Uttarkashi 1991 and Chamba 1995 earthquakes, is used for the soil-structure interaction (SSI) analysis. The continuum model can simultaneously simulate structure, soil, interfaces, and geogrids in the OpenSees framework. Soil is modeled with PressureDependentMultiYield (PDMY) material models with Quad element that provides stress-strain at gauss points and is calibrated to predict the behavior of Ganga sand. The model analyzed with a tied degree of freedom contact reveals that the system responses align with the shake table experimental results. An attempt is made to study the responses of footing structure and geosynthetics with unreinforced and reinforced bases with varying parameters. The result shows that geogrid reinforces shallow foundation effectively reduces the settlement by 60%.

Keywords: settlement, shallow foundation, SSI, continuum FEM

Procedia PDF Downloads 194
2783 Effect of Ethanol and Betadine on the Preformed Biofilm of Staphylococcus Aureus Isolated from Urinary Catheter

Authors: Kara Terki Ibtissem, Hassaine Hafida, Bellifa Samia

Abstract:

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

Keywords: staphylococcus aureus, biofilm, urinary catheter, ethanol

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2782 Egg Hatching Inhibition Activity of Volatile Oils Extracted from Some Medicinal and Aromatic Plants against Root-Knot Nematode Meloidogyne hapla

Authors: Anil F. Felek, Mehmet M. Ozcan, Faruk Akyazi

Abstract:

Volatile oils of medicinal and aromatic plants are important for managing nematological problems in agriculture. In present study, volatile oils extracted from five medicinal and aromatic plants including Origanum onites (flower+steam+leaf), Salvia officinalis (leaf), Lippia citriodora (leaf+seed), Mentha spicata (leaf) and Mentha longifolia (leaf) were tested for egg hatching inhibition activity against root-knot nematode Meloidogyne hapla under laboratory conditions. The essential oils were extracted using water distillation method with a Clevenger system. For the homogenisation process of the oils, 2% gum arabic solution was used and 4 µl oils was added into 1ml filtered gum arabic solution to prepare the last stock solution. 5 ml of stock solution and 1 ml of M. hapla egg suspension (about 100 eggs) were added into petri dishes. Gum arabic solution was used as control. Seven days after exposure to oils at room temperature (26±2 °C), the cumulative hatched and unhatched eggs were counted under 40X inverted light microscope and Abbott’s formula was used to calculate egg hatching inhibition rates. As a result, the highest inhibition rate was found as 54% for O. onites. In addition, the other inhibition rates varied as 31.4%, 21.6%, 23.8%, 25.67% for the other plants, S. officinalis, M. longifolia, M. spicata and L. citriodora, respectively. Carvacrol was found as the main component (68.8%) of O. onites followed by Thujone 27.77% for S. officinalis, I-Menthone 76.92% for M. longifolia, Carvone 27.05% for M. spicata and Citral 19.32% for L. citriodora.

Keywords: egg hatching, Meloidogyne hapla, medicinal and aromatic plants, root-knot nematodes, volatile oils

Procedia PDF Downloads 266
2781 Exploring the Intrinsic Ecology and Suitable Density of Historic Districts Through a Comparative Analysis of Ancient and Modern Ecological Smart Practices

Authors: Hu Changjuan, Gong Cong, Long Hao

Abstract:

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

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

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