Search results for: pulse duration
Commenced in January 2007
Frequency: Monthly
Edition: International
Paper Count: 2008

Search results for: pulse duration

1528 Comprehensive Study of X-Ray Emission by APF Plasma Focus Device

Authors: M. Habibi

Abstract:

The time-resolved studies of soft and hard X-ray were carried out over a wide range of argon pressures by employing an array of eight filtered photo PIN diodes and a scintillation detector, simultaneously. In 50% of the discharges, the soft X-ray is seen to be emitted in short multiple pulses corresponding to different compression, whereas it is a single pulse for hard X-rays corresponding to only the first strong compression. It should be stated that multiple compressions dominantly occur at low pressures and high pressures are mostly in the single compression regime. In 43% of the discharges, at all pressures except for optimum pressure, the first period is characterized by two or more sharp peaks.The X–ray signal intensity during the second and subsequent compressions is much smaller than the first compression.

Keywords: plasma focus device, SXR, HXR, Pin-diode, argon plasma

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1527 Auditory Effects among 18-45 Years Old Workers of a Textile Plant in Seeduwa, Sri Lanka

Authors: P. G. S. Madushani, L. D. Illeperuma

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Abstract Noise is one of the most common physical hazards in industrial settings. The prevalence of Noise Induced Hearing Loss (NIHL) is on the rise with increasedduration of exposure and the increase in the severity of hearing loss. The purpose of the study was to determine auditory effects among textile workers and to establish associations between the degree of hearing loss and exposure duration, degree of hearing loss and noise level and the proportion of hearing related complaints. A cross sectional descriptive study using purposive sampling was carried out. An interviewer administered questionnaire and Distortion Product Oto Acoustic Emission (DPOAE) hearing screening on 127 (72 female and 55 male) textile workers of the selected textile plant in Seeduwa, Sri Lanka was done (Age: M= 31.16, SD=7.75). Noise measurements were done in six sections of the factory and average noise levels were obtained. Diagnostic hearing evaluations were done for 60 (57.75%) subjects, referred from the DPOAE hearing screening test. The degree of hearing loss and the exposure duration had a significant association in the high frequency region of 4 kHz to 8 kHz (p < 0.05). Noise levels fluctuated between 90.3±0.8 dBA and 50.6. ±0.52 dBA. 30.83% of workers reported having NIHL. Most of the workers (33.9%) complained difficulty in conversing in noisy backgrounds. Other complaints as tinnitus, dizziness, ear fullness and headache were reported in less than 30%. workers who were exposed to noise for more than 15 years were affected with NIHL in the high frequency region. Administrative controls and engineering controls need to be implemented to manage hazardous noise levels in industrial settings. Hearing Conservation Programs should be initiated and implemented for textile workers.

Keywords: textile industry, NIHL, degree of hearing loss, noise levels, auditory effects

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1526 Efficiency of Wood Vinegar Mixed with Some Plants Extract against the Housefly (Musca domestica L.)

Authors: U. Pangnakorn, S. Kanlaya

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The efficiency of wood vinegar mixed with each individual of three plants extract such as: citronella grass (Cymbopogon nardus), neem seed (Azadirachta indica A. Juss), and yam bean seed (Pachyrhizus erosus Urb.) were tested against the second instar larvae of housefly (Musca domestica L.). Steam distillation was used for extraction of the citronella grass while neem and yam bean were simple extracted by fermentation with ethyl alcohol. Toxicity test was evaluated in laboratory based on two methods of larvicidal bioassay: topical application method (contact poison) and feeding method (stomach poison). Larval mortality was observed daily and larval survivability was recorded until the survived larvae developed to pupae and adults. The study resulted that treatment of wood vinegar mixed with citronella grass showed the highest larval mortality by topical application method (50.0%) and by feeding method (80.0%). However, treatment of mixed wood vinegar and neem seed showed the longest pupal duration to 25 day and 32 days for topical application method and feeding method respectively. Additional, larval duration on treated M. domestica larvae was extended to 13 days for topical application method and 11 days for feeding method. Thus, the feeding method gave higher efficiency compared with the topical application method.

Keywords: housefly (Musca domestica L.), neem seed (Azadirachta indica), citronella grass (Cymbopogon nardus), yam bean seed (Pachyrhizus erosus), mortality

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1525 The Relationship between Level of Anxiety and the Development of Children with Growth Hormone Deficiency

Authors: Ewa Mojs, Katarzyna Wiechec, Maia Kubiak, Wlodzimierz Samborski

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Interactions between mother’s psychological condition and child’s health status are complex and derive from the nature of the mother-child relationship. The aim of the study was to analyze the issue of anxiety amongst mothers of short children in the aspect of growth hormone therapy. The study was based on a group of 101 mothers of originally short-statured children – 70 with growth hormone deficiency (GHD) treated with recombinant human growth hormone (rhGH) and 31 undergoing the diagnostic process, without any treatment. Collected medical data included child's gender, height and weight, chronological age, bone age delay, and rhGH therapy duration. For all children, the height SDS and BMI SDS were calculated. To evaluate anxiety in mothers, the Spielberger State-Trait Anxiety Inventory (STAI) was used. Obtained results revealed low trait anxiety levels, with no statistically significant differences between the groups. State anxiety levels were average when mothers of all children were analyzed together, but when divided into groups, statistical differences appeared. Mothers of children without diagnosis and treatment had significantly higher levels of state anxiety than mothers of children with GHD receiving appropriate therapy. These results show, that the occurrence of growth failure in children is not related to high maternal trait anxiety, but the lack of diagnosis and lack of appropriate treatment generates higher levels of maternal state anxiety than the process of rh GH therapy in the offspring. Commencement of growth hormone therapy induce a substantial reduction of the state anxiety in mothers, and the duration of treatment causes its further decrease.

Keywords: anxiety, development, growth hormone deficiency, motherhood

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1524 Wireless Integrated Switched Oscillator Impulse Generator with Application in Wireless Passive Electric Field Sensors

Authors: S. Mohammadzamani, B. Kordi

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Wireless electric field sensors are in high demand in the number of applications that requires measuring electric field such as investigations of high power systems and testing the high voltage apparatus. Passive wireless electric field sensors are most desired since they do not require a source of power and are interrogated wirelessly. A passive wireless electric field sensor has been designed and fabricated by our research group. In the wireless interrogation system of the sensor, a wireless radio frequency impulse generator needs to be employed. A compact wireless impulse generator composed of an integrated resonant switched oscillator (SWO) and a pulse-radiating antenna has been designed and fabricated in this research. The fundamental of Switched Oscillators was introduced by C.E.Baum. A Switched Oscillator consists of a low impedance transmission line charged by a DC source, through large impedance at desired frequencies and terminated to a high impedance antenna at one end and a fast closing switch at the other end. Once the line is charged, the switch will close and short-circuit the transmission line. Therefore, a fast transient wave will be generated and travels along the transmission line. Because of the mismatch between the antenna and the transmission line, only a part of fast transient wave will be radiated, and a portion of the fast-transient wave will reflect back. At the other end of the transmission line, there is a closed switch. Consequently, a second reflection with a reversed sign will propagate towards the antenna and the wave continues back and forth. hence, at the terminal of the antenna, there will be a series of positive and negative pulses with descending amplitude. In this research a single ended quarter wavelength Switched Oscillator has been designed and simulated at 800MHz. The simulation results show that the designed Switched Oscillator generates pulses with decreasing amplitude at the frequency of 800MHz with the maximum amplitude of 10V and bandwidth of about 10MHz at the antenna end. The switched oscillator has been fabricated using a 6cm long coaxial cable transmission line which is charged by a DC source and an 8cm monopole antenna as the pulse radiating antenna. A 90V gas discharge switch has been employed as the fast closing switch. The Switched oscillator sends a series of pulses with decreasing amplitude at the frequency of 790MHz with the maximum amplitude of 0.3V in the distance of 30 cm.

Keywords: electric field measurement, impulse radiating antenna, switched oscillator, wireless impulse generator

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1523 Laser Induced Transient Current in Quasi-One-Dimensional Nanostructure

Authors: Tokuei Sako

Abstract:

Light-induced ultrafast charge transfer in low-dimensional nanostructure has been studied by a model of a few electrons confined in a 1D electrostatic potential coupled to electrodes at both ends and subjected to an ultrashort pulsed laser field. The time-propagation of the one- and two-electron wave packets has been calculated by integrating the time-dependent Schrödinger equation by the symplectic integrator method with uniform Fourier grid. The temporal behavior of the resultant light-induced current in the studied systems has been discussed with respect to the central frequency and pulse width of the applied laser fields.

Keywords: pulsed laser field, nanowire, wave packet, quantum dots, conductivity

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1522 Characterization of Oxide Layer Developed during Tribo-Interaction of Zircaloys

Authors: Bharat Kumar, Deepak Kumar, Vijay Chaudhry

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Zirconium alloys are used as core components of nuclear reactors due to their high wear resistance, good corrosion properties, and good mechanical stability at high temperatures. The present work simulates the contact between the calandria tube and the liquid injection shutdown system (LISS) nozzle. The Calandria tube is the outer covering of the pressure tube. Water flows inside the pressure tube through fuel claddings which produces vibration in the pressure tube along with vibration in the calandria tube. Fretting wear takes place at the point of contact between the calandria tube and the LISS nozzle. Fretting tests were performed under different conditions, such as; varying fretting duration (i.e., 1 to 4 hours), varying frequency (i.e., 5 to 6.5 Hz), and varying amplitude (100 to 400 µm). The formation of the oxide layer was observed during the fretting wear test; as a result, the worn product. The worn surfaces were analyzed with scanning electron microscopy (SEM) to analyze the wear mechanism involved in the fretting test, and Energy dispersive x-ray spectroscopy (EDS) and Raman spectroscopy were used to confirm the presence of an oxide layer on the worn surface. The oxide layer becomes more uniform with fretting duration in case of water submerged condition as compared to dry contact condition. The oxide layer is deeply removed at high amplitude due to the change of wear mechanism from adhesion to abrasion, as confirmed by the presence of micro ploughing and micro cutting. Low amplitude fretting favors the formation of the tribo-oxide layer.

Keywords: tribo-oxide layer, wear, mechanically mixed layer, zircaloy

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1521 Clinical Prediction Score for Ruptured Appendicitis In ED

Authors: Thidathit Prachanukool, Chaiyaporn Yuksen, Welawat Tienpratarn, Sorravit Savatmongkorngul, Panvilai Tangkulpanich, Chetsadakon Jenpanitpong, Yuranan Phootothum, Malivan Phontabtim, Promphet Nuanprom

Abstract:

Background: Ruptured appendicitis has a high morbidity and mortality and requires immediate surgery. The Alvarado Score is used as a tool to predict the risk of acute appendicitis, but there is no such score for predicting rupture. This study aimed to developed the prediction score to determine the likelihood of ruptured appendicitis in an Asian population. Methods: This study was diagnostic, retrospectively cross-sectional and exploratory model at the Emergency Medicine Department in Ramathibodi Hospital between March 2016 and March 2018. The inclusion criteria were age >15 years and an available pathology report after appendectomy. Clinical factors included gender, age>60 years, right lower quadrant pain, migratory pain, nausea and/or vomiting, diarrhea, anorexia, fever>37.3°C, rebound tenderness, guarding, white blood cell count, polymorphonuclear white blood cells (PMN)>75%, and the pain duration before presentation. The predictive model and prediction score for ruptured appendicitis was developed by multivariable logistic regression analysis. Result: During the study period, 480 patients met the inclusion criteria; of these, 77 (16%) had ruptured appendicitis. Five independent factors were predictive of rupture, age>60 years, fever>37.3°C, guarding, PMN>75%, and duration of pain>24 hours to presentation. A score > 6 increased the likelihood ratio of ruptured appendicitis by 3.88 times. Conclusion: Using the Ramathibodi Welawat Ruptured Appendicitis Score. (RAMA WeRA Score) developed in this study, a score of > 6 was associated with ruptured appendicitis.

Keywords: predictive model, risk score, ruptured appendicitis, emergency room

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1520 Endoscopic Treatment of Esophageal Injuries Using Vacuum Therapy

Authors: Murad Gasanov, Shagen Danielyan, Ali Gasanov, Yuri Teterin, Peter Yartsev

Abstract:

Background: Despite the advances made in modern surgery, the treatment of patients with esophageal injuries remains one of the most topical and complex issues. In recent years, high-technology minimally invasive methods, such as endoscopic vacuum therapy (EVT) in the treatment of esophageal injuries. The effectiveness of EVT has been sufficiently studied in case of failure of esophageal anastomoses, however the application of this method in case of mechanical esophageal injuries is limited by a small series of observations, indicating the necessity of additional study. Aim: The aim was to аnalyzed of own experience in the use of endoscopic vacuum therapy (EVT) in a comprehensive examination of patients with esophageal injuries. Methods: We analyzed the results of treatment of 24 patients with mechanical injuries of the esophagus for the period 2019-2021. Complex treatment of patients included the use of minimally invasive technologies, including percutaneous endoscopic gastrostomy (PEG), EVT and video-assisted thoracoscopic debridement. Evaluation of the effectiveness of treatment was carried out using multislice computed tomography (MSCT), endoscopy and laboratory tests. The duration of inpatient treatment and the duration of EVT, the number of system replacements, complications and mortality were taken into account. Result: EVT in patients with mechanical injuries of the esophagus allowed to achieve epithelialization of the esophageal defect in 21 patients (87.5%) in the form of linear scar on the site of perforation or pseudodiverticulum. Complications were noted in 4 patients (16.6%), including bleeding (2) and and esophageal stenosis in the perforation area (2). Lethal outcome was in one observation (4.2%). Conclusion. EVT may be the method of choice in complex treatment in patients with esophageal lesions.

Keywords: esophagus injuries, damage to the esophagus, perforation of the esophagus, spontaneous perforation of the esophagus, mediastinitis, endoscopic vacuum therapy

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1519 Effect of Palatal Lift Prosthesis on Speech Clarity in Flaccid Dysarthria

Authors: Firas Alfwaress, Abdelraheem Bebers Abdelhadi Hamasha, Maha Abu Awaad

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Objectives: The aim of the present study was to investigate the effect of Palatal Lift Prosthesis (PLP) on speech clarity in patients with Flaccid Dysarthria. Five speech measures were investigated including Nasalance Scores, Diadchokinetic (DDK), Vowel Duration, airflow, and Sound Intensity. Participants: Twelve (7 Males and 5 females) native speakers of Jordanian Arabic with Flaccid Dysarthria following stroke, traumatic brain injury, and amyotrophic lateral sclerosis were included. The age of the participants ranged from 8–65 years with an average of 31.75 years. Design: Nasalance Scores, Diadchokinetic rate, Vowel Duration, and Sound Intensity were obtained using the Nasometer II, Model 6450 in three conditions. The first condition included obtaining the five measures without wearing the customized Palatal Lift Prosthesis. The second and third conditions included obtaining the five measures immediately after wearing the Palatal Lift Prosthesis and three months later. Results: Palatal lift prosthesis was found to be effective in individuals with flaccid dysarthria. Results showed decrease in the Nasalance Scores for the syllable repetition tasks and vowel prolongation tasks when comparing the means in the pre PLP with the post PLP at p≤0.001 except for the /m/ prolongation task. Results showed increased DDK repetition task, airflow amount, and sound intensity, and a decrease in vowel length at p≤0.001. Conclusions: The use of palatal lift prosthesis is effective in improving the speech of patients with flaccid dysarthria.

Keywords: palatal lift prosthesis, flaccid dysarthria, hypernasality, speech clarity, diadchokinetic rate

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1518 Proposed Design of an Optimized Transient Cavity Picosecond Ultraviolet Laser

Authors: Marilou Cadatal-Raduban, Minh Hong Pham, Duong Van Pham, Tu Nguyen Xuan, Mui Viet Luong, Kohei Yamanoi, Toshihiko Shimizu, Nobuhiko Sarukura, Hung Dai Nguyen

Abstract:

There is a great deal of interest in developing all-solid-state tunable ultrashort pulsed lasers emitting in the ultraviolet (UV) region for applications such as micromachining, investigation of charge carrier relaxation in conductors, and probing of ultrafast chemical processes. However, direct short-pulse generation is not as straight forward in solid-state gain media as it is for near-IR tunable solid-state lasers such as Ti:sapphire due to the difficulty of obtaining continuous wave laser operation, which is required for Kerr lens mode-locking schemes utilizing spatial or temporal Kerr type nonlinearity. In this work, the transient cavity method, which was reported to generate ultrashort laser pulses in dye lasers, is extended to a solid-state gain medium. Ce:LiCAF was chosen among the rare-earth-doped fluoride laser crystals emitting in the UV region because of its broad tunability (from 280 to 325 nm) and enough bandwidth to generate 3-fs pulses, sufficiently large effective gain cross section (6.0 x10⁻¹⁸ cm²) favorable for oscillators, and a high saturation fluence (115 mJ/cm²). Numerical simulations are performed to investigate the spectro-temporal evolution of the broadband UV laser emission from Ce:LiCAF, represented as a system of two homogeneous broadened singlet states, by solving the rate equations extended to multiple wavelengths. The goal is to find the appropriate cavity length and Q-factor to achieve the optimal photon cavity decay time and pumping energy for resonator transients that will lead to ps UV laser emission from a Ce:LiCAF crystal pumped by the fourth harmonics (266nm) of a Nd:YAG laser. Results show that a single ps pulse can be generated from a 1-mm, 1 mol% Ce³⁺-doped LiCAF crystal using an output coupler with 10% reflectivity (low-Q) and an oscillator cavity that is 2-mm long (short cavity). This technique can be extended to other fluoride-based solid-state laser gain media.

Keywords: rare-earth-doped fluoride gain medium, transient cavity, ultrashort laser, ultraviolet laser

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1517 Physiological Indicators and Stress Index of Scavenging Chickens at Lafarge and Dangote Cement Factory Areas of Ogun State

Authors: Oluwadele Joshua Femi, Akinlabi Ebenezer Yemi, Onaopemipo Adeitan, Kazeem Bello, Anthony Ekeocha, Miraim Tawose

Abstract:

This study was carried out to determine the physiological and stress index of scavenging chickens in LAFARGE (Ewekoro) and Dangote (Ibese) Cement Factories Area of Ogun State. One hundred adult scavenging chickens comprising of 25 chickens from LAFARGE, Dangote and respective adjourning communities (Imasayi and Wasimi) were used. Experimental birds were caught at night on their perch and kept in cages till the next morning. Data were collected on rectal temperature, pulse rate, and respiratory rate of the birds. Also, 5ml blood was collected through the wing vein of the chickens in each location using a sterilized needle and syringe and transported to laboratory for analysis. Significant (P<0.05) highest pulse rate (215.64 beat/minute) and respiratory rate (19.90 breaths/minute) were recorded among scavenging chickens at LAFARGE (Ewekoro) Area and the least (198.61 beat/minute and 16.93 breaths/minute, respectively) at Imasayi. There was no significant (P>0.05) difference in the rectal temperature of the birds in the study area. Significant (P<0.05) differences were also recorded in the Packed Cell Volume (PCV), Hemoglobin (Hb), White Blood Cell (WBC), Monocyte, and Glucose level of the chickens in study area with the highest (P<0.05) Packed Cell Volume (28.06%) and Haemoglobin (4.01g/dl) recorded in Ibese and the least Packed Cell Volume (22.00%) and Haemoglobin (288g/dl) in Imasayi. Highest (P<0.05) Monocyte (4.28%) and glucose (256.53g/dl) were recorded among scavenging chickens at Dangote (Ibese) while the least Monocyte (0.00%) and Glucose (194.53g/dl) was recorded among chickens at Wasimi. Highest (P<0.05) White Blood Cell (6488.89×103µl) was recorded among chickens at Ewekoro and the lowest value in Ibese (4388.44×103µl). There was no significant (P>0.05) difference in the Heterophyl, Lymphocyte, Basophyl and Heterophyl/Lymphocyte ratio of the chickens in the study Area. The study concluded that chickens reared at LAFARGE (Ewekoro) were stressed and had comprised welfare and health status compared to Dangote (Ibese) cement area and other agrarian communities. Effective environmental mitigation programme should be put in place to enhance the welfare of the scavenging chickens in LAFARGE Cement Factory Area.

Keywords: blood, chicken, poisonous substances, pack cell volume, communities

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1516 Difference in Virulence Factor Genes Between Transient and Persistent Streptococcus Uberis Intramammary Infection in Dairy Cattle

Authors: Anyaphat Srithanasuwan, Noppason Pangprasit, Montira Intanon, Phongsakorn Chuammitri, Witaya Suriyasathaporn, Ynte H. Schukken

Abstract:

Streptococcus uberis is one of the most common mastitis-causing pathogens, with a wide range of intramammary infection (IMI) durations and pathogenicity. This study aimed to compare shared or unique virulence factor gene clusters distinguishing persistent and transient strains of S. uberis. A total of 139 S. uberis strains were isolated from three small-holder dairy herds with a high prevalence of S. uberis mastitis. The duration of IMI was used to categorize bacteria into two groups: transient and persistent strains with an IMI duration of less than 1 month and longer than 2 months, respectively. Six representative S. uberis strains, three from each group (transience and persistence) were selected for analysis. All transient strains exhibited multi-locus sequence types (MLST), indicating a highly diverse population of transient S. uberis. In contrast, MLST of persistent strains was available in an online database (pubMLST). Identification of virulence genes was performed using whole-genome sequencing (WGS) data. Differences in genomic size and number of virulent genes were found. For example, the BCA gene or alpha-c protein and the gene associated with capsule formation (hasAB), found in persistent strains, are important for attachment and invasion, as well as the evasion of the antimicrobial mechanisms and survival persistence, respectively. These findings suggest a genetic-level difference between the two strain types. Consequently, a comprehensive study of 139 S. uberis isolates will be conducted to perform an in-depth genetic assessment through WGS analysis on an Illumina platform.

Keywords: Streptococcus Uberis, mastitis, whole genome sequence, intramammary infection, persistent S. Uberis, transient s. Uberis

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1515 Predictability of Pupil Mydriasis as a Biomarker for Diabetes

Authors: Naveen Kumar Challa, Pavan Verıkıcherla, Madhubalan, Ashısh Sharma

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Aim: Aim of the study was to find whether any difference exists in pupil mydriasis measured with Orbscan in non-diabetic and type 2 diabetic patients at various intervals after installation of Tropicamide 0.8% and Phenylephrine 5%. Methods: the Observational study conducted at a tertiary care eye hospital during September 2014 to March 2015. 240 eyes from 120 patients (40 non-diabetic, 80 diabetic) were dilated with Tropicamide 0.8% and Phenylephrine 5%. One drop of a drug was installed twice. The second drop is installed at 20 minutes after installation of the first drop. In two groups’ pupil diameter was measured before installation of drops and also at 15, 30, 45 and 60 minutes after installation of the first drop using both Orbscan. Result: Mean age of the non-diabetic group is 48.67 ± 7.93 years; Diabetic group is 59.97 ± 8.77 years. Mean duration of Diabetes was 7.01 ± 5.05 years. Mean pupil diameter measured with Orbscan before installation of the drops and also at 15, 30, 45 and 60 minutes after installation of first drop in non-diabetic group was 4.18 ± 0.64mm, 6.15 ± 0.41mm, 7.76 ±0.34, 9.59 ± 0.30, and 9.97 ± 0.10 mm respectively and for the diabetic group it was 4.00 ± 0.56 mm, 5.53 ± 0.52 mm, 7.018 ± 0.58mm, 8.25±0.51mm and 9.18 ± 0.46mm respectively. The mean difference between the mean pupil diameters of the non-diabetic and diabetic group shows a significant difference (P< 0.01) at all intervals except before dilatation. There is a significant negative correlation (r = 0.78 – 0.92) between the duration of diabetes and pupil dilatation at all intervals after installation of the drops. There is also significant difference (P< 0.005) in the mean values of pupil diameter between non retinopathy diabetic subjects and diabetic retinopathy subjects at all intervals after installation of drops. Conclusion: People attending eye clinic, whose pupil mydriasis values falls below the normal may be referred for diabetic evaluation. If normative data is established for the pupil size in Indian population using Orbscan then the values fall under normative data could be a predictor for diabetes. This would in turn help ophthalmologist to detect the diabetes at an early stage and prevent the complications resulting from the diabetes.

Keywords: diabetes mellitus, pupil diameter, orbscan, tropicamide

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1514 SVM-DTC Using for PMSM Speed Tracking Control

Authors: Kendouci Khedidja, Mazari Benyounes, Benhadria Mohamed Rachid, Dadi Rachida

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In recent years, direct torque control (DTC) has become an alternative to the well-known vector control especially for permanent magnet synchronous motor (PMSM). However, it presents a problem of field linkage and torque ripple. In order to solve this problem, the conventional DTC is combined with space vector pulse width modulation (SVPWM). This control theory has achieved great success in the control of PMSM. That has become a hotspot for resolving. The main objective of this paper gives us an introduction of the DTC and SVPWM-DTC control theory of PMSM which has been simulating on each part of the system via Matlab/Simulink based on the mathematical modeling. Moreover, the outcome of the simulation proved that the improved SVPWM- DTC of PMSM has a good dynamic and static performance.

Keywords: PMSM, DTC, SVM, speed control

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1513 A Simplified Model of the Control System with PFM

Authors: Bekmurza H. Aitchanov, Sholpan K. Aitchanova, Olimzhon A. Baimuratov, Aitkul N. Aldibekova

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This work considers the automated control system (ACS) of milk quality during its magnetic field processing. For achieving high level of quality control methods were applied transformation of complex nonlinear systems in a linearized system with a less complex structure. Presented ACS is adjustable by seven parameters: mass fraction of fat, mass fraction of dry skim milk residues (DSMR), density, mass fraction of added water, temperature, mass fraction of protein, acidity.

Keywords: fluids magnetization, nuclear magnetic resonance, automated control system, dynamic pulse-frequency modulator, PFM, nonlinear systems, structural model

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1512 A Clinical Audit on Screening Women with Subfertility Using Transvaginal Scan and Hysterosalpingo Contrast Sonography

Authors: Aarti M. Shetty, Estela Davoodi, Subrata Gangooly, Anita Rao-Coppisetty

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Background: Testing Patency of Fallopian Tubes is among one of the several protocols for investigating Subfertile Couples. Both, Hysterosalpingogram (HSG) and Laparoscopy and dye test have been used as Tubal patency test for several years, with well-known limitation. Hysterosalpingo Contrast Sonography (HyCoSy) can be used as an alternative tool to HSG, to screen patency of Fallopian tubes, with an advantage of being non-ionising, and also, use of transvaginal scan to diagnose pelvic pathology. Aim: To determine the indication and analyse the performance of transvaginal scan and HyCoSy in Broomfield Hospital. Methods: We retrospectively analysed fertility workup of 282 women, who attended HyCoSy clinic at our institution from January 2015 to June 2016. An Audit proforma was designed, to aid data collection. Data was collected from patient notes and electronic records, which included patient demographics; age, parity, type of subfertility (primary or secondary), duration of subfertility, past medical history and base line investigation (hormone profile and semen analysis). Findings of the transvaginal scan, HyCoSy and Laparoscopy were also noted. Results: The most common indication for referral were as a part of primary fertility workup on couples who had failure to conceive despite intercourse for a year, other indication for referral were recurrent miscarriage, history of ectopic pregnancy, post reversal of sterilization(vasectomy and tuboplasty), Post Gynaecology surgery(Loop excision, cone biopsy) and amenorrhea. Basic Fertility workup showed 34% men had abnormal semen analysis. HyCoSy was successfully completed in 270 (95%) women using ExEm foam and Transvaginal Scan. Of the 270 patients, 535 tubes were examined in total. 495/535 (93%) tubes were reported as patent, 40/535 (7.5%) tubes were reported as blocked. A total of 17 (6.3%) patients required laparoscopy and dye test after HyCoSy. In these 17 patients, 32 tubes were examined under laparoscopy, and 21 tubes had findings similar to HyCoSy, with a concordance rate of 65%. In addition to this, 41 patients had some form of pelvic pathology (endometrial polyp, fibroid, cervical polyp, fibroid, bicornuate uterus) detected during transvaginal scan, who referred to corrective surgeries after attending HyCoSy Clinic. Conclusion: Our audit shows that HyCoSy and Transvaginal scan can be a reliable screening test for low risk women. Furthermore, it has competitive diagnostic accuracy to HSG in identifying tubal patency, with an additional advantage of screening for pelvic pathology. With addition of 3D Scan, pulse Doppler and other non-invasive imaging modality, HyCoSy may potentially replace Laparoscopy and chromopertubation in near future.

Keywords: hysterosalpingo contrast sonography (HyCoSy), transvaginal scan, tubal infertility, tubal patency test

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1511 Prevalence and Occupational Factors Associated with Low Back Pain among the Female Garment Workers: A Cross-Sectional Study in Bangladesh

Authors: Fazle Rabbi, Mashuda Khanom Tithi, Tasnim Mirza, Sanjida Rowshan Anannya, Ahmed Hossain

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Background: Low Back Pain (LBP) is one of the common health problems among the garment workers that causes workers absenteeism from the work. The purpose of the study is to identify the association between occupational factors and LBP among the female garment workers in Bangladesh. Materials and Methods: A cross-sectional study was conducted with 487 female garment workers from three compliant garment factories of Bangladesh. Face-to-face interview on four different LBP measures along with questions on socio-demographic, occupational, and physical factors were used to collect the data. Result: The prevalence rates for LBP lasts for at least one day during the last six months, chronic pain, intense pain, and seeking medical care for LBP were found 63.04%, 38.60%, 13.76%, and 18.89%, respectively among the female garments workers. The multivariate logistic regression analysis indicates that duration of employment (>5 years), regular weight bearing and extended weekly working hours (>48 hours) are positively associated with LBP. Besides, age, BMI, family income, marital status and number of children are also found positively associated with the LBP measures. Conclusion: The prevalence of LBP among female garment workers in Bangladesh is found high. The duration of employment (>5 years), regular weight bearing and extended weekly working hours (>48 hours) play a significant role in developing LBP among the female workers. Factories need to consider training programs on the appropriate technique of weight bearing. It is also important to conduct regular screening programs to identify LBP, especially with married, overweight/obese and older age group to reduce the occurrence of LBP.

Keywords: Bangladesh, garment workers, low back pain, occupational health

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1510 Rheological Properties of Red Beet Root Juice Squeezed from Ultrasounicated Red Beet Root Slices

Authors: M. Çevik, S. Sabancı, D. Tezcan, C. Çelebi, F. İçier

Abstract:

Ultrasound technology is the one of the non-thermal food processing method in recent years which has been used widely in the food industry. Ultrasound application in the food industry is divided into two groups: low and high intensity ultrasound application. While low intensity ultrasound is used to obtain information about physicochemical properties of foods, high intensity ultrasound is used to extract bioactive components and to inactivate microorganisms and enzymes. In this study, the ultrasound pre-treatment at a constant power (1500 W) and fixed frequency (20 kHz) was applied to the red beetroot slices having the dimension of 25×25×50 mm at the constant temperature (25°C) for different application times (0, 5, 10, 15 and 20 min). The red beet root slices pretreated with ultrasonication was squeezed immediately. The changes on rheological properties of red beet root juice depending on ultrasonication duration applied to slices were investigated. Rheological measurements were conducted by using Brookfield viscometer (LVDV-II Pro, USA). Shear stress-shear rate data was obtained from experimental measurements for 0-200 rpm range by using spindle 18. Rheological properties of juice were determined by fitting this data to some rheological models (Newtonian, Bingham, Power Law, Herschel Bulkley). It was investigated that the best model was Power Law model for both untreated red beet root juice (R2=0.991, χ2=0.0007, RMSE=0.0247) and red beetroot juice produced from ultrasonicated slices (R2=0.993, χ2=0.0006, RMSE=0.0216 for 20 min pre-treatment). k (consistency coefficient) and n (flow behavior index) values of red beetroot juices were not affected from the duration of ultrasonication applied to the slices. Ultrasound treatment does not result in any changes on the rheological properties of red beetroot juice. This can be explained by lack of ability to homogenize of the intensity of applied ultrasound.

Keywords: ultrasonication, rheology, red beet root slice, juice

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1509 Study of the Influence of Non Genetic Factors Affecting over Nutrition Students in Ayutthaya Province, Thailand

Authors: Thananyada Buapian

Abstract:

Overnutrition is emerging as a morbid disease in developing and Westernized countries. Because of its comorbidity diseases, it is cost-effective to prevent and manage this disease earlier. In Thailand, this alarming disease has long been studied, but the prevalence is still higher than that in the past. Physicians should recognize it well and have a definite direction to face and combat this dangerous disease. Rapid changes in the tremendous figure of overnutrition students indicate that genetic factors are not the primary determinants since human genes have remained unchanged for a century. This study aims to assess the prevalence of overnutrition students and to investigate the non-genetic factors affecting over nutrition students. A cross-sectional school-based survey was conducted. A two-stage sampling was adopted. Respondents included 1,850 students in grades 4 to 6 in Ayutthaya Province. An anthropometric measurement and questionnaire were developed. Childhood over nutrition was defined as a weight-for-height Z-score above +2SD of NCHS/WHO references. About thirty three percent of the children were over nutrition in Ayutthaya province. Stepwise multiple logistic regression analysis showed that 8 statistically significant non genetic factors explain the variation of childhood over nutrition by 18 percent. Sex is the prime factor to explain the variation of childhood over nutrition, followed by duration of light physical activities, duration of moderate physical activities, having been breastfed, the presence of a healthy role model of the caregiver, number of siblings, birth order, and occupation of the caregiver, respectively. Non genetic factors, especially the subjects’ demographic and physical activities, as well as the caregivers’ background and family environment, should be considered in viable approach to remedy this health imbalance in children.

Keywords: non genetic factors, non-genetic, over nutrition, over nutrition students

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1508 Changes on Some Physical and Chemical Properties of Red Beetroot Juice during Ultrasound Pretreatment

Authors: Serdal Sabanci, Mutlu Çevik, Derya Tezcan, Cansu Çelebi, Filiz Içier

Abstract:

Ultrasound is defined as sound waves having frequencies higher than 20 kHz, which is greater than the limits of the human hearing range. In recent years, ultrasonic treatment is an emerging technology being used increasingly in the food industry. It is applied as an alternative technique for different purposes such as microbial and enzyme inactivation, extraction, drying, filtration, crystallization, degas, cutting etc. Red beetroot (Beta vulgaris L.) is a root vegetable which is rich in mineral components, folic acid, dietary fiber, anthocyanin pigments. In this study, the application of low frequency high intensity ultrasound to the red beetroot slices and red beetroot juice for different treatment times (0, 5, 10, 15, 20 min) was investigated. Ultrasonicated red beetroot slices were also squeezed immediately. Changes on colour, betanin, pH and titratable acidity properties of red beetroot juices (the ultrasonicated juice (UJ) and the juice from ultrasonicated slices (JUS)) were determined. Although there was no significant difference statistically in the changes of color value of JUS samples due to ultrasound application (p>0.05), the color properties of UJ samples ultrasonicated for low durations were statistically different from raw material (p<0.05). The difference between color values of UJ and raw material disappeared (p>0.05) as the ultrasonication duration increased. The application of ultrasound to red beet root slices adversely affected and decreased the betanin content of JUS samples. On the other hand, the betanin content of UJ samples increased as the ultrasonication duration increased. Ultrasound treatment did not affect pH and titratable acidity of red beetroot juices statistically (p>0.05). The results suggest that ultrasound technology is the simple and economical technique which may successfully be employed for the processing of red beetroot juice with improved color and betanin quality. However, further investigation is still needed to confirm this.

Keywords: red beetroot, ultrasound, color, betanin

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1507 Nonlinear Optical Properties for Three Level Atoms at Resonance and Off-Resonance with Laser Coupled Beams

Authors: Suad M. Abuzariba, Eman O. Mafaa

Abstract:

For three level atom interacts with a laser beam, the effect of changing resonance and off-resonance frequencies has been studied. Furthermore, a clear distortion has been seen in both the real and imaginary parts of the electric susceptibility with increasing the frequency of the coupled laser beams so that reaching the off-resonance interaction. With increasing the Rabi frequency of the laser pulse that in resonance with the lower transition the distortion will produce a new peak in the electric susceptibility parts, in both the real and imaginary ones.

Keywords: electric susceptibility, resonance frequency off-resonance frequency, three level atom, laser

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1506 The Effects of the Introduction of a One-day Waiting Period on Absences for Ordinary Illness of Public Employees

Authors: Mohamed Ali Ben Halima, Malik Koubi, Joseph Lanfranchi, Yohan Wloczysiak

Abstract:

This article assesses the consequences on the frequency and duration of ordinary sick leave of the January 2012 and 2018 reforms modifying the scope of sick leave reimbursement in the French civil service. These reforms introduce a one-day waiting period which removes the compensation for the first day of ordinary sick leave. In order to evaluate these reforms, we use an administrative database from the National Pension Fund for local public employees (FPT). The first important result of our data analysis is that the one-day waiting period was not introduced at the same time in the French Local Public Service establishments, or even never in some. This peculiarity allows for an identification strategy using a difference-in-differences method based on the definition at each date of groups of employees treated and not treated by the reform, since establishments that apply the one-day waiting period coexist with establishments that do not apply it. Two types of estimators are used for this evaluation: individual and time fixed effects estimators and DIDM estimators which correct for the biases of the Two Way Fixed Effects one. The results confirm that the change in the sick pay system decreases the probability of having at least one ordinary sick leave as well as the number and duration of these episodes. On the other hand, the estimates show that longer leave episodes are not less affected than shorter ones. Finally, the validity tests of the estimators support the results obtained for the second period of 2018-2019, but suggest estimation biases for the period 2012-2013. The extent to which the endogeneity of the choices of implementation of the reform at the local level impact these estimates needs to be further tested.

Keywords: sick leave, one-day waiting period, territorial civil service, public policy evaluation

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1505 Informational Support, Anxiety and Satisfaction with Care among Family Caregivers of Patients Admitted in Critical Care Units of B.P. Koirala Institute of Health Sciences, Nepal

Authors: Rosy Chaudhary, Pushpa Parajuli

Abstract:

Background and Objectives: Informational support to family members has a significant potential for reducing this distress related to hospitalization of their patient into the critical care unit, enabling them to cope better and support the patient. The objective of the study is to assess family members’ perception of informational support, anxiety, satisfaction with care and to reveal the association with selected socio-demographic variables and to investigate the correlation between informational support, anxiety and satisfaction with care. Materials and Methods: A descriptive cross-sectional study was conducted in 39 family caregivers of patients admitted in critical care unit of BPKIHS(B.P. Koirala Institute of Health Sciences). Consecutive sampling technique was used wherein data was collected over duration of one month using interview schedule. Descriptive and inferential statistics were used. Results: The mean age of the respondents was 34.97 ± 10.64 and two third (66.70%) were male. Mean score for informational support was 25.72(SD = 5.66; theoretical range of 10 - 40). Mean anxiety was 10.41 (SD = 5.02; theoretical range of 7 - 21). Mean score for satisfaction with care was 40.77 (SD = 6.77; theoretical range of 14 - 64). A moderate positive correlation was found between informational support and satisfaction with care (r = 0.551, p < .001) and a moderate negative correlation was found between anxiety and satisfaction with care (r = -0.590; p = 0.000). No relationship was noted between informational support and anxiety. Conclusion: The informational support and satisfaction of the family caregivers with the care provided to their patients was satisfactory. More than three fourth of the family caregivers had anxiety; the factors associated being educational status of the caregivers, the family income and duration of visiting hours. There was positive correlation between informational support and satisfaction with care provided justifying the need for comprehensive information to the family caregivers by the health personnel. There was negative correlation between anxiety and satisfaction with care.

Keywords: anxiety, caregivers, critical care unit, informational support, family

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1504 The Moderating Roles of Bedtime Activities and Anxiety and Depression in the Relationship between Attention-Deficit/Hyperactivity Disorder and Sleep Problems in Children

Authors: Lian Tong, Yan Ye, Qiong Yan

Abstract:

Background: Children with attention-deficit/hyperactivity disorder (ADHD) often experience sleep problems, but the comorbidity mechanism has not been sufficiently studied. This study aimed to determine the comorbidity of ADHD and sleep problems as well as the moderating effects of bedtime activities and depression/anxiety symptoms on the relationship between ADHD and sleep problems. Methods: We recruited 934 primary students from third to fifth grade and their parents by stratified random sampling from three primary schools in Shanghai, China. This study used parent-reported versions of the ADHD Rating Scale-IV, Children’s Sleep Habits Questionnaire, and Achenbach Child Behavior Checklist. We used hierarchical linear regression analysis to clarify the moderating effects of bedtime activities and depression/anxiety symptoms. Results: We found that children with more ADHD symptoms had shorter sleep durations and more sleep problems on weekdays. Screen time before bedtime strengthened the relationship between ADHD and sleep-disordered breathing. Children with more screen time were more likely to have sleep onset delay, while those with less screen time had more sleep onset problems with increasing ADHD symptoms. The high bedtime eating group experienced more night waking with increasing ADHD symptoms compared with the low bedtime eating group. Anxiety/depression exacerbated total sleep problems and further interacted with ADHD symptoms to predict sleep length and sleep duration problems. Conclusions: Bedtime activities and emotional problems had important moderating effects on the relationship between ADHD and sleep problems. These findings indicate that appropriate bedtime management and emotional management may reduce sleep problems and improve sleep duration for children with ADHD symptoms.

Keywords: ADHD, sleep problems, anxiety/depression, bedtime activities, children

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1503 Pulsed Vortex Flow in Low–Temperature Range Heat Pipes

Authors: A. V. Seryakov

Abstract:

The work presents part calculation and part experimental research of the intensification of heat-transfer characteristics of medium-temperature heat pipes. Presented is a vapour jet nozzle, similar to the Laval nozzle, surrounded by a capillary-porous insert along the full length of the heat pipe axial to the direction of heat flow. This increases velocity of the vapour flow, heat-transfer coefficient and pulse rate of two-phase vapour flow.

Keywords: medium-temperature range heat pipes, capillary-porous insert, capillary steam injectors, Laval nozzle, condensation sensor

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1502 Application of an Analytical Model to Obtain Daily Flow Duration Curves for Different Hydrological Regimes in Switzerland

Authors: Ana Clara Santos, Maria Manuela Portela, Bettina Schaefli

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This work assesses the performance of an analytical model framework to generate daily flow duration curves, FDCs, based on climatic characteristics of the catchments and on their streamflow recession coefficients. According to the analytical model framework, precipitation is considered to be a stochastic process, modeled as a marked Poisson process, and recession is considered to be deterministic, with parameters that can be computed based on different models. The analytical model framework was tested for three case studies with different hydrological regimes located in Switzerland: pluvial, snow-dominated and glacier. For that purpose, five time intervals were analyzed (the four meteorological seasons and the civil year) and two developments of the model were tested: one considering a linear recession model and the other adopting a nonlinear recession model. Those developments were combined with recession coefficients obtained from two different approaches: forward and inverse estimation. The performance of the analytical framework when considering forward parameter estimation is poor in comparison with the inverse estimation for both, linear and nonlinear models. For the pluvial catchment, the inverse estimation shows exceptional good results, especially for the nonlinear model, clearing suggesting that the model has the ability to describe FDCs. For the snow-dominated and glacier catchments the seasonal results are better than the annual ones suggesting that the model can describe streamflows in those conditions and that future efforts should focus on improving and combining seasonal curves instead of considering single annual ones.

Keywords: analytical streamflow distribution, stochastic process, linear and non-linear recession, hydrological modelling, daily discharges

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1501 Radical Scavenging Activity of Protein Extracts from Pulse and Oleaginous Seeds

Authors: Silvia Gastaldello, Maria Grillo, Luca Tassoni, Claudio Maran, Stefano Balbo

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Antioxidants are nowadays attractive not only for the countless benefits to the human and animal health, but also for the perspective of use as food preservative instead of synthetic chemical molecules. In this study, the radical scavenging activity of six protein extracts from pulse and oleaginous seeds was evaluated. The selected matrices are Pisum sativum (yellow pea from two different origins), Carthamus tinctorius (safflower), Helianthus annuus (sunflower), Lupinus luteus cv Mister (lupin) and Glycine max (soybean), since they are economically interesting for both human and animal nutrition. The seeds were grinded and proteins extracted from 20mg powder with a specific vegetal-extraction kit. Proteins have been quantified through Bradford protocol and scavenging activity was revealed using DPPH assay, based on radical DPPH (2,2-diphenyl-1-picrylhydrazyl) absorbance decrease in the presence of antioxidants molecules. Different concentrations of the protein extract (1, 5, 10, 50, 100, 500 µg/ml) were mixed with DPPH solution (DPPH 0,004% in ethanol 70% v/v). Ascorbic acid was used as a scavenging activity standard reference, at the same six concentrations of protein extracts, while DPPH solution was used as control. Samples and standard were prepared in triplicate and incubated for 30 minutes in dark at room temperature, the absorbance was read at 517nm (ABS30). Average and standard deviation of absorbance values were calculated for each concentration of samples and standard. Statistical analysis using t-students and p-value were performed to assess the statistical significance of the scavenging activity difference between the samples (or standard) and control (ABSctrl). The percentage of antioxidant activity has been calculated using the formula [(ABSctrl-ABS30)/ABSctrl]*100. The obtained results demonstrate that all matrices showed antioxidant activity. Ascorbic acid, used as standard, exhibits a 96% scavenging activity at the concentration of 500 µg/ml. At the same conditions, sunflower, safflower and yellow peas revealed the highest antioxidant performance among the matrices analyzed, with an activity of 74%, 68% and 70% respectively (p < 0.005). Although lupin and soybean exhibit a lower antioxidant activity compared to the other matrices, they showed a percentage of 46 and 36 respectively. All these data suggest the possibility to use undervalued edible matrices as antioxidants source. However, further studies are necessary to investigate a possible synergic effect of several matrices as well as the impact of industrial processes for a large-scale approach.

Keywords: antioxidants, DPPH assay, natural matrices, vegetal proteins

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1500 The Catalytic Properties of PtSn/Al2O3 for Acetic Acid Hydrogenation

Authors: Mingchuan Zhou, Haitao Zhang, Hongfang Ma, Weiyong Ying

Abstract:

Alumina supported platinum and tin catalysts with different loadings of Pt and Sn were prepared and characterized by low temperature N2 adsorption/desorption, H2-temperature programed reduction and CO pulse chemisorption. Pt and Sn below 1% loading were suitable for acetic acid hydrogenation. The best performance over 0.75Pt1Sn/Al2O3 can reach 87.55% conversion of acetic acid and 47.39% selectivity of ethanol. The operating conditions of acetic acid hydrogenation over 1Pt1Sn/Al2O3 were investigated. High reaction temperature can enhance the conversion of acetic acid, but it decreased total selectivity of ethanol and acetyl acetate. High pressure and low weight hourly space velocity were beneficial to both conversion of acetic acid and selectivity to ethanol.

Keywords: acetic acid, hydrogenation, operating condition, PtSn

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1499 Receptor-Independent Effects of Endocannabinoid Anandamide on Contractility and Electrophysiological Properties of Rat Ventricular Myocytes

Authors: Lina T. Al Kury, Oleg I. Voitychuk, Ramiz M. Ali, Sehamuddin Galadari, Keun-Hang Susan Yang, Frank Christopher Howarth, Yaroslav M. Shuba, Murat Oz

Abstract:

A role for anandamide (N-arachidonoyl ethanolamide; AEA), a major endocannabinoid, in the cardiovascular system in various pathological conditions has been reported in earlier studies. In the present work, we have hypothesized that the antiarrhythmic effects reported for AEA are due to its negative inotropic effect and altered action potential (AP) characteristics. Therefore, we tested the effects of AEA on contractility and electrophysiological properties of rat ventricular myocytes. Video edge detection was used to measure myocyte shortening. Intracellular Ca2+ was measured in cells loaded with the fluorescent indicator fura-2 AM. Whole-cell patch-clamp technique was employed to investigate the effect of AEA on the characteristics of APs. AEA (1 μM) caused a significant decrease in the amplitudes of electrically-evoked myocyte shortening and Ca2+ transients and significantly decreased the duration of AP. The effect of AEA on myocyte shortening and AP characteristics was not altered in the presence of pertussis toxin (PTX, 2 µg/ml for 4 h), AM251 and SR141716 (cannabinoid type 1 receptor antagonists) or AM630 and SR 144528 (cannabinoid type 2 receptor antagonists). Furthermore, AEA inhibited voltage-activated inward Na+ (INa) and Ca2+ (IL,Ca) currents; major ionic currents shaping the APs in ventricular myocytes, in a voltage and PTX-independent manner. Collectively, the results suggest that AEA depresses ventricular myocyte contractility, by decreasing the action potential duration (APD), and inhibits the function of voltage-dependent Na+ and L-type Ca2+ channels in a manner independent of cannabinoid receptors. This mechanism may be importantly involved in the antiarrhythmic effects of anandamide.

Keywords: action potential, anandamide, cannabinoid receptor, endocannabinoid, ventricular myocytes

Procedia PDF Downloads 345