Search results for: uniform delay

Authors: S. Yesmin, N. F.Rahman, R. Akther, T. Begum, T. Tahmid, T. Chowdury, S. Afrin, J. D. Hamadani

Abstract:

Abstract: Maternal depression is one of the risk factors of developmental delay in young children in low-income countries. Maternal depressions during pregnancy are rarely reported in Bangladesh. Objectives: The purpose of the present study was to examine the efficacy of a community based psychosocial intervention on women with mild to moderate depressive illness during the perinatal period and on their children from birth to 12 months on mothers’ mental status and their infants’ growth and development. Methodology: The study followed a prospective longitudinal approach with a randomized controlled design. Total 250 pregnant women aged between 15 and 40 years were enrolled in their third trimester of pregnancy of which 125 women were in the intervention group and 125 in the control group. Women in the intervention group received the “Thinking Healthy (CBT based) program” at their home setting, from their last month of pregnancy till 10 months after delivery. Their children received psychosocial stimulation from birth till 12 months. The following instruments were applied to get the outcome information- Bangla version of Edinburgh Postnatal Depression Scale (BEPDS), Prenatal Attachment Inventory (PAI), Maternal Attachment Inventory (MAI), Bayley Scale of Infant Development-Third version (Bayley–III) and Family Care Indicator (FCI). In addition, sever morbidity; breastfeeding, immunization, socio-economic and demographic information were collected. Data were collected at three time points viz. baseline, midline (6 months after delivery) and endline (12 months after delivery). Results: There was no significant difference between any of the socioeconomic and demographic variables at baseline. A very preliminary analysis of the data shows an intervention effect on Socioemotional behaviour of children at endline (p<0.001), motor development at midline (p=0.016) and at endline (p=0.065), language development at midline (p=0.004) and at endline (p=0.023), cognitive development at midline (p=0.008) and at endline (p=0.002), and quality of psychosocial stimulation at midline (p=0.023) and at endline (p=0.010). EPDS at baseline was not different between the groups (p=0.419), but there was a significant improvement at midline (p=0.027) and at endline (p=0.024) between the groups following the intervention. Conclusion: Psychosocial intervention is found effective in reducing women’s low and moderate depressive illness to cope with mental health problem and improving development of young children in Bangladesh.

Keywords: mental health, maternal depression, infant development, CBT, EPDS

Procedia PDF Downloads 246

Authors: W. Meron Mebrahtu, R. Absi

Abstract:

Velocity distribution in turbulent open-channel flows is organized in a complex manner. This is due to the large spatial and temporal variability of fluid motion resulting from the free-surface turbulent flow condition. This phenomenon is complicated further due to the complex geometry of channels and the presence of solids transported. Thus, several efforts were made to understand the phenomenon and obtain accurate mathematical models that are suitable for engineering applications. However, predictions are inaccurate because oversimplified assumptions are involved in modeling this complex phenomenon. Therefore, the aim of this work is to study velocity distribution profiles and obtain simple, more accurate, and predictive mathematical models. Particular focus will be made on the acceptable simplification of the general transport equations and an accurate representation of eddy viscosity. Wide rectangular open-channel seems suitable to begin the study; other assumptions are smooth-wall, and sediment-free flow under steady and uniform flow conditions. These assumptions will allow examining the effect of the bottom wall and the free surface only, which is a necessary step before dealing with more complex flow scenarios. For this flow condition, two ordinary differential equations are obtained for velocity profiles; from the Reynolds-averaged Navier-Stokes (RANS) equation and equilibrium consideration between turbulent kinetic energy (TKE) production and dissipation. Then different analytic models for eddy viscosity, TKE, and mixing length were assessed. Computation results for velocity profiles were compared to experimental data for different flow conditions and the well-known linear, log, and log-wake laws. Results show that the model based on the RANS equation provides more accurate velocity profiles. In the viscous sublayer and buffer layer, the method based on Prandtl’s eddy viscosity model and Van Driest mixing length give a more precise result. For the log layer and outer region, a mixing length equation derived from Von Karman’s similarity hypothesis provides the best agreement with measured data except near the free surface where an additional correction based on a damping function for eddy viscosity is used. This method allows more accurate velocity profiles with the same value of the damping coefficient that is valid under different flow conditions. This work continues with investigating narrow channels, complex geometries, and the effect of solids transported in sewers.

Keywords: accuracy, eddy viscosity, sewers, velocity profile

Procedia PDF Downloads 85

Authors: Magdalena Hasplova, Katerina Ivanova

Abstract:

Perinatal palliative care is a relatively young and developing field that includes the care of a fetus or newborn with a life-threatening or limiting defect and his family. However, the training of midwives in perinatal palliative care is insufficient and midwives do not feel prepared for this aspect of their work. This fact can affect the barriers to communication with the mother or family of the endangered child. The main aim was to analyze the awareness of midwifery students on the issue of perinatal palliative care in the Czech Republic. Based on the analysis, draw attention to possible communication barriers that may be caused by insufficient information. The research was carried out using a qualitative method, the method of data collection was a semi-structured interview. Eleven female students took part in the research, and the respondents were selected using the Snowballing method. Some methods of grounded theory (open coding and category creation) were used to analyze the data. Based on the results of the research, questions were set in a questionnaire focused on communication barriers between mothers (family) and health care professionals in the care of newborns with life-threatening or limiting disabilities. Based on the analysis of data, categories 1 were determined. Knowledge of perinatal palliative care 2. Education 3. Practical experience 4. Readiness and concerns in the provision of perinatal palliative care 6. Supervision. The questions in the questionnaire were then derived taking into account the data obtained, and the operationalization of health literacy in the field of perinatal palliative care was performed. The analysis of the interviews revealed that the education of midwives in the Czech Republic in the issue of perinatal palliative care is not uniform. The research confirmed the insufficient knowledge and skills of midwifery students preparing to provide perinatal palliative care. Respondents reported feelings of unpreparedness in the areas of communication with a woman after perinatal loss, psychological support for a woman and her family, the care of a stillborn or dying child, or self-coping with death. The questions in the questionnaire then develop these areas. We assumed that by analyzing and interpreting the data obtained from our research, we will help to better understand the concerns and motivations of students in providing holistic perinatal palliative care. We came to the conclusion that it would be appropriate to set up a unified and comprehensive education on this issue in the Czech Republic. Healthcare professionals are in a unique position that can positively or negatively affect the intensity of perinatal loss. Already properly set up education of health professionals leads to overcoming barriers in communication between health professionals and the family, experiencing perinatal loss.

Keywords: midwife, perinatal loss, perinatal palliative care, communication, barriers, mothers, family

Procedia PDF Downloads 89

Authors: Akbarova Gulnozakhon

Abstract:

Relevance. Physical exercises can prolong the function of the growth zones of long tubular bones, delay the fusion of the epiphyses and diaphyses of bones and, thus, increase the growth of the body. At the same time, intensive strength exercises can accelerate the process of ossification of bone growth zones and slow down their growth in length. The influence of physical exercises on the process of biological maturation is noted. Gymnastics, which requires intense speed and strength loads, delays puberty. On the other hand, it is indicated that the relatively slow puberty of gymnasts is associated with the selection of girls with a special somatotype in this sport. It was found that the later onset of menstruation in female athletes does not have a negative effect on the maturation process and fertility (the ability to procreate). Observations are made about the normalizing influence of sports on the puberty of girls. The purpose of the study. Our goal is to study physical activity of varying intensity on the formation of secondary sexual characteristics and hormonal status of girls in adolescence. Each biological process peculiar to a given organism is not in a stationary state, but fluctuates with a certain frequency. According to the duration, there are, for example, circadian cycles, and infradian cycles, a typical example of which is the menstrual cycle. Materials and methods, results. Violations of menstrual function in athletes were detected by applying a questionnaire survey that contains several paragraphs and sub-paragraphs where passport data, anthropometric indicators, taking into account anthropometric indices, information about the menstrual cycle are indicated. Of 135 female athletes aged 1-3 to 16 years engaged in various sports - gymnasts, menstrual function disorders were noted in 86.7% (primary or secondary amenorrhea, irregular MC), in swimming-in 57.1%. The general condition also changes during the menstrual cycle. In a large percentage of cases, athletes indicate an increase in irritability in the premenstrual (45%) and menstrual (36%) phases. During these phases, girls note an increase in fatigue of 46.5% and 58% (respectively). In girls, secondary sexual characteristics continue to form during puberty and the clearest indicator of the onset of puberty is the age of the onset of the first menstruation - menarche. Conclusions. 1. Physical exercise has a positive effect on all major systems of the body and thus promotes health.2. Along with a beneficial effect on human health, physical exercise, if the requirements of sports are not observed, can be harmful.

Keywords: girls health, anthropometric, physical development, reproductive health

Procedia PDF Downloads 71

Authors: Jessica Scher Lisa, Eric Shyman

Abstract:

Autism spectrum disorder (ASD) is a neuro-developmental disorder that is characterized by persistent deficits in social communication and social interaction (i.e. deficits in social-emotional reciprocity, nonverbal communicative behaviors, and establishing/maintaining social relationships), as well as by the presence of repetitive behaviors and perseverative areas of interest (i.e. stereotyped or receptive motor movements, use of objects, or speech, rigidity, restricted interests, and hypo or hyperactivity to sensory input or unusual interest in sensory aspects of the environment). Additionally, diagnoses of ASD require the presentation of symptoms in the early developmental period, marked impairments in adaptive functioning, and a lack of explanation by general intellectual impairment or global developmental delay (although these conditions may be co-occurring). Over the past several decades, many theories have been developed in an effort to explain the root cause of ASD in terms of atypical central cognitive processes. The field of neuroscience is increasingly finding structural and functional differences between autistic and neurotypical individuals using neuro-imaging technology. One main area this research has focused upon is in visuospatial processing, with specific attention to the notion of ‘weak central coherence’ (WCC). This paper offers an analysis of findings from selected studies in order to explore research that challenges the ‘deficit’ characterization of a weak central coherence theory as opposed to a ‘superiority’ characterization of strong local coherence. The weak central coherence theory has long been both supported and refuted in the ASD literature and has most recently been increasingly challenged by advances in neuroscience. The selected studies lend evidence to the notion of amplified localized perception rather than deficient global perception. In other words, WCC may represent superiority in ‘local processing’ rather than a deficit in global processing. Additionally, the right hemisphere and the specific area of the extrastriate appear to be key in both the visual and lexicosemantic process. Overactivity in the striate region seems to suggest inaccuracy in semantic language, which lends itself to support for the link between the striate region and the atypical organization of the lexicosemantic system in ASD.

Keywords: autism spectrum disorder, neurology, visual processing, weak coherence

Procedia PDF Downloads 98

Authors: Indu Gaur, Neha Bhadauria, Shilpi Shilpi, Susmita Goswami, Prem D. Sharma, Prabir K. Paul

Abstract:

The concept of organic agriculture has been accepted as novelty in Indian society, but there is no data available on the human pathogens colonizing plant parts due to such practices. Also, the pattern and mechanism of their colonization need to be understood in order to devise possible strategies for their prevention. In the present study, human pathogenic bacteria were isolated from organically grown tomato plants and five of them were identified as Klebsiella pneumoniae, Enterobacter ludwigii, Serratia fonticola, Stenotrophomonas maltophilia and Chryseobacterium jejuense. Tomato plants were grown in controlled aseptic conditions with 25±1˚C, 70% humidity and 12 hour L/D photoperiod. Six weeks old plants were divided into 6 groups of 25 plants each and treated as follows: Group 1: K. pneumonia, Group 2: E. ludwigii, Group 3: S. fonticola, Group 4: S. maltophilia, Group 5: C. jejuense, Group 6: Sterile distilled water (control). The inoculums for all treatments were prepared by overnight growth with uniform concentration of 108 cells/ml. Leaf samples from above groups were collected at 0.5, 2, 4, 6 and 24 hours post inoculation for the colony forming unit counts (CFU/cm2 of leaf area) of individual pathogens using leaf impression method. These CFU counts were used for the in vivo colonization assay and adherence assay of individual pathogens. Also, resistance of these pathogens to at least 12 antibiotics was studied. Based on these findings S. fonticola was found to be most prominently colonizing the phylloplane of tomato and was further studied. Tomato plants grown in controlled aseptic conditions same as mentioned above were divided into 2 groups of 25 plants each and treated as follows: Group 1: S. fonticola, Group 2: Sterile distilled water (control). Leaf samples from above groups were collected at 0, 24, 48, 72 and 96 hours post inoculation and homogenized in suitable buffers for surface and cell wall protein isolation. Protein samples thus obtained were subjected to isocratic SDS-gel electrophoresis and analyzed. It was observed that presence of S. fonticola could induce the expression of at least 3 additional cell wall proteins at different time intervals. Surface proteins also showed variation in the expression pattern at different sampling intervals. Further identification of these proteins by MALDI-MS and bioinformatics tools revealed the gene(s) involved in the interaction of S. fonticola with tomato phylloplane.

Keywords: cell wall proteins, human pathogenic bacteria, phylloplane, solanum lycopersicum

Procedia PDF Downloads 206

Authors: Ece Cigdem Mutlu, Burak Alakent

Abstract:

Maintaining the quality of manufactured products at a desired level depends on the stability of process dispersion and location parameters and detection of perturbations in these parameters as promptly as possible. Shewhart control chart is the most widely used technique in statistical process monitoring to monitor the quality of products and control process mean and variability. In the application of Xbar control charts, sample standard deviation and sample mean are known to be the most efficient conventional estimators in determining process dispersion and location parameters, respectively, based on the assumption of independent and normally distributed datasets. On the other hand, there is no guarantee that the real-world data would be normally distributed. In the cases of estimated process parameters from Phase I data clouded with outliers, efficiency of traditional estimators is significantly reduced, and performance of Xbar charts are undesirably low, e.g. occasional outliers in the rational subgroups in Phase I data set may considerably affect the sample mean and standard deviation, resulting a serious delay in detection of inferior products in Phase II. For more efficient application of control charts, it is required to use robust estimators against contaminations, which may exist in Phase I. In the current study, we present a simple approach to construct robust Xbar control charts using average distance to the median, Qn-estimator of scale, M-estimator of scale with logistic psi-function in the estimation of process dispersion parameter, and Harrell-Davis qth quantile estimator, Hodge-Lehmann estimator and M-estimator of location with Huber psi-function and logistic psi-function in the estimation of process location parameter. Phase I efficiency of proposed estimators and Phase II performance of Xbar charts constructed from these estimators are compared with the conventional mean and standard deviation statistics both under normality and against diffuse-localized and symmetric-asymmetric contaminations using 50,000 Monte Carlo simulations on MATLAB. Consequently, it is found that robust estimators yield parameter estimates with higher efficiency against all types of contaminations, and Xbar charts constructed using robust estimators have higher power in detecting disturbances, compared to conventional methods. Additionally, utilizing individuals charts to screen outlier subgroups and employing different combination of dispersion and location estimators on subgroups and individual observations are found to improve the performance of Xbar charts.

Keywords: average run length, M-estimators, quality control, robust estimators

Procedia PDF Downloads 170

Authors: Amarachi Delight Onyemachi, Gregory Ikechukwu Onwuka

Abstract:

The growing consumer trend for natural ingredients, functional foods with health benefits and the perceived risk of carcinogenesis associated with synthetic antioxidants have forced food manufacturers to look for alternatives for producing healthy and safe food. Herbs and spices are cheap, natural and harmless sources of antioxidants which can delay and prevent lipid oxidation of food products and also confer its unique organoleptic properties and health benefits to food products. The Nigerian climate has been proven to be conducive for the production of spices and herbs and is blessed bountifully with a wide range of them. Five selected Nigerian herbs and spices Piper guieense, Xylopia aethopica, Gongronema latifolium and Ocimum gratissimum were evaluated for their ability to act as radical scavengers. The spices were extracted with 80% ethanol and evaluated using total phenolic capacity (TPC), DPPH (1,1-diph diphenyl-2-picrylhydrazyl radical) ABTS (2,2’azinobis-(3-ethylbenzthiazoline-6-sulfonic acid)), total antioxidant capacity (TAC), reducing power (RP) assays. The TPC ranged from 5.33 µg GAE/mg (in Gongronema latifolium) to 15.55 µg GAE/mg (in Ocimum gratissimum). The DPPH and ABTS scavenging activity of the extracts ranged from 0.23-0.36 IC50 mg/ml and 2.32-7.25 Trolox equivalent % respectively. The TAC and RP of the extract ranged from 6.73-10.64 µg AAE/mg and 3.52-10.19 µg AAE/mg. The result of percentage yield of the extract ranged from as low as 9.94% in Gongronema latifolium and to as high as 23.85% in Xylopia aethopica. A very strong positive relationship existed between the total antioxidant capacity and total phenolic content of the tested herbs and spices (R2=0.96). All of the extracts exhibited different extent of strong antioxidant activity, high antioxidant activity was found in Ocimum gratissimum and Gongronema latifolium with the least. However, Gongronema latifolium possessed the highest total antioxidant capacity. These data confirm the appreciable antioxidant potentials and high phenolic content of Nigerian herbs and spices, thereby providing justification for their use in dishes and functional foods, prevention of cellular damage caused by free radicals and use as natural antioxidants in the food industry for prevention of lipid oxidation in food products. However, to utilize these natural antioxidants in food products, further analysis and studies of their behaviour in food systems at varying temperature, pH conditions and ionic concentrations should be carried out to displace the use of synthetic antioxidants like BHT and BHA.

Keywords: Antioxidant, free radicals, herbs, phenolic, spices

Procedia PDF Downloads 228

Authors: Bao-Fang Wen, Meng-Na Dai, Gao-Pei Zhu, Chen-Xi Zhang, Jing Sun, Xun-Bao Yin, Yu-Han Zhao, Hong-Wei Sun, Wei-Fen Zhang

Abstract:

A drug-loaded nanoparticles containing berberine hydrochloride (BH/FA-CTS-NPs) was prepared. The physicochemical characterizations of BH/FA-CTS-NPs and the inhibitory effect on the HeLa cells were investigated. Folic acid-conjugated chitosan (FA-CTS) was prepared by amino reaction of folic acid active ester and chitosan molecules; BH/FA-CTS-NPs were prepared using ionic cross-linking technique with BH as a model drug. The morphology and particle size were determined by Transmission Electron Microscope (TEM). The average diameters and polydispersity index (PDI) were evaluated by Dynamic Light Scattering (DLS). The interaction between various components and the nanocomplex were characterized by Fourier Transform Infrared Spectroscopy (FT-IR). The entrapment efficiency (EE), drug-loading (DL) and in vitro release were studied by UV spectrophotometer. The effect of cell anti-migratory and anti-invasive actions of BH/FA-CTS-NPs were investigated using MTT assays, wound healing assays, Annexin-V-FITC single staining assays, and flow cytometry, respectively. HeLa nude mice subcutaneously transplanted tumor model was established and treated with different drugs to observe the effect of BH/FA-CTS-NPs in vivo on HeLa bearing tumor. The BH/FA-CTS-NPs prepared in this experiment have a regular shape, uniform particle size, and no aggregation phenomenon. The results of DLS showed that mean particle size, PDI and Zeta potential of BH/FA-CTS NPs were (249.2 ± 3.6) nm, 0.129 ± 0.09, 33.6 ± 2.09, respectively, and the average diameter and PDI were stable in 90 days. The results of FT-IR demonstrated that the characteristic peaks of FA-CTS and BH/FA-CTS-NPs confirmed that FA-CTS cross-linked successfully and BH was encapsulated in NPs. The EE and DL amount were (79.3 ± 3.12) % and (7.24 ± 1.41) %, respectively. The results of in vitro release study indicated that the cumulative release of BH/FA-CTS NPs was (89.48±2.81) % in phosphate-buffered saline (PBS, pH 7.4) within 48h; these results by MTT assays and wund healing assays indicated that BH/FA-CTS NPs not only inhibited the proliferation of HeLa cells in a concentration and time-dependent manner but can induce apoptosis as well. The subcutaneous xenograft tumor formation rate of human cervical cancer cell line HeLa in nude mice was 98% after inoculation for 2 weeks. Compared with BH group and BH/CTS-NPs group, the xenograft tumor growth of BH/FA-CTS-NPs group was obviously slower; the result indicated that BH/FA-CTS-NPs could significantly inhibit the growth of HeLa xenograft tumor. BH/FA-CTS NPs with the sustained release effect could be prepared successfully by the ionic crosslinking method. Considering these properties, block proliferation and impairing the migration of the HeLa cell line, BH/FA-CTS NPs could be an important compound for consideration in the treatment of cervical cancer.

Keywords: folic-acid, chitosan, berberine hydrochloride, nanoparticles, cervical cancer

Procedia PDF Downloads 96

Authors: Ibrahim M Hassan, Lorna Que, Michael Rutland

Abstract:

Type I SOD is usually diagnosed by anatomical imaging such as ultrasound, CT and MRCP. However, the types II and III SOD yield negative results despite the presence of significant symptoms. In particular, the type III is difficult to diagnose due to the absence of significant biochemical or anatomical abnormalities. Nuclear Medicine can aid in this diagnostic dilemma by demonstrating functional changes in the bile flow. Low dose Morphine (0.04mg/Kg) stimulates the tone of the sphincter of Oddi (SO) and its usefulness has been shown in diagnosing SOD by causing a delay in bile flow when compared to a non morphine provoked - baseline scan. This work expands on that process by using sublingual GTN at 60 minutes post tracer and morphine injection to relax the SO and induce an improvement in bile outflow, and in some cases show immediate relief of morphine induced abdominal pain. The criteria for positive SOD are as follows: if during the first hour of the morphine provocation showed (1) delayed intrahepatic biliary ducts tracer accumulation; plus (2) delayed appearance but persistent retention of activity in the common bile duct, and (3) delayed bile flow into the duodenum. In addition, patients who required GTN within the first hour to relieve abdominal pain were regarded as highly supportive of the diagnosis. Retrospective analysis of 85 patients (pts) (78F and 6M) referred for suspected SOD (type III) who had been intensively investigated because of recurrent right upper quadrant or abdominal pain post cholecystectomy. 99mTc-HIDA scan with morphine-provocation is performed followed by GTN at 60 minutes post tracer injection and a further thirty minutes of dynamic imaging are acquired. 30 pts were negative. 55 pts were regarded as positive for SOD and 38/55 (60%) of these patients with an abnormal result were further evaluated with a baseline 99mTc-HIDA. As expected, all 38 pts showed better bile flow characteristics than during the morphine provocation. 20/55 (36%) patients were treated by ERCP sphincterotomy and the rest were managed conservatively by medical therapy. In all cases regarded as positive for SOD, the sublingual GTN at 60 minutes showed immediate improvement in bile flow. 11/55(20%) who developed severe post-morphine abdominal pain were relieved by GTN almost instantaneously. We propose that GTN is a useful agent in the diagnosis of SOD when performing 99mTc-HIDA scan and that the satisfactory response to the sublingual GTN could offer additional information in patients who have severe pain at the time the procedure or when presenting to the emergency unit because of biliary pain. And also in determining whether a trial of medical therapy may be used before considering surgery.

Keywords: GTN, HIDA, MORPHINE, SOD

Procedia PDF Downloads 277

Authors: Naima Jannat, Ariful Islam, Sharafat Hossain

Abstract:

Due to the involvement of the large target volume, Craniospinal Irradiation makes it challenging to achieve a uniform dose, and it requires different isocenters. This isocentric junction needs to shift after every five fractions to overcome the possibility of hot and cold spots. This study aims to evaluate the Planning Target Volume coverage & sparing Organ at Risk between two techniques and shows that the Field Alignment Technique does not need replanning and resetting. Planning method for Craniospinal Irradiation by Eclipse treatment planning system Field Alignment and Extended Source to Surface Distance technique was developed where 36 Gy in 20 Fraction at the rate of 1.8 Gy was prescribed. The patient was immobilized in the prone position. In the Field Alignment technique, the plan consists of half beam blocked parallel opposed cranium and a single posterior cervicospine field was developed by sharing the same isocenter, which obviates divergence matching. Further, a single field was created to treat the remaining lumbosacral spine. Matching between the inferior diverging edge of the cervicospine field and the superior diverging edge of a lumbosacral field, the field alignment option was used, which automatically matches the field edge divergence as per the field alignment rule in Eclipse Treatment Planning System where the couch was set to 2700. In the Extended Source to Surface Distance technique, two parallel opposed fields were created for the cranium, and a single posterior cervicospine field was created where the Source to Surface Distance was from 120-140 cm. Dose Volume Histograms were obtained for each organ contoured and for each technique used. In all, the patient’s maximum dose to Planning Target Volume is higher for the Extended Source to Surface Distance technique to Field Alignment technique. The dose to all surrounding structures was increased with the use of a single Extended Source to Surface Distance when compared to the Field Alignment technique. The average mean dose to Eye, Brain Steam, Kidney, Oesophagus, Heart, Liver, Lung, and Ovaries were respectively (58% & 60 %), (103% & 98%), (13% & 15%), (10% & 63%), (12% & 16%), (33% & 30%), (14% & 18%), (69% & 61%) for Field Alignment and Extended Source to Surface Distance technique. However, the clinical target volume at the spine junction site received a less homogeneous dose with the Field Alignment technique as compared to Extended Source to Surface Distance. We conclude that, although the use of a single field Extended Source to Surface Distance delivered a more homogenous, but its maximum dose is higher than the Field Alignment technique. Also, a huge advantage of the Field Alignment technique for Craniospinal Irradiation is that it doesn’t need replanning and resetting up of patients after every five fractions and 95% prescribed dose was received by more than 95% of the Planning Target Volume in all the plane with the acceptable hot spot.

Keywords: craniospinalirradiation, cranium, cervicospine, immobilize, lumbosacral spine

Procedia PDF Downloads 76

Authors: Merilin Ivanova Ivanova, Kalin Dimitrov Atanasov, Stefan Petrov Enchev

Abstract:

Backgroud: Neuromyelitis optica spectrum disorder, also known as Devic’s disease, is a relapsing demyelinating autoimmune inflammatory disorder of the central nervous system associated with anti-aquaporin 4 (AQP4) antibodies that can manifest with devastating secondary neurological deficits. Most commonly affected are the optic nerves and the spinal cord-clinically this is often presented with optic neuritis (loss of vision), transverse myelitis(weakness or paralysis of extremities),lack of bladder and bowel control, numbness. APS is a core clinical entity of NMOSD and adds to the clinical representation the following symptoms: intractable nausea, vomiting and hiccup, it usually occurs isolated at onset, and can lead to a significant delay in the diagnosis. The condition may have features similar to multiple sclerosis (MS) but the episodes are worse in NMO and it is treated differently. It could be relapsing or monophasic. Possible complications are visual field defects and motor impairment, with potential blindness and irreversible motor deficits. In severe cases, myogenic respiratory failure ensues. The incidence of reported cases is approximately 0.3–4.4 per 100,000. Paediatric cases of NMOSD are rare but have been reported occasionally, comprising less than 5% of the reported cases. Objective: The case serves to show the difficulty when it comes to the diagnostic processes regarding a rare autoimmune disease with non- specific symptoms, taking large interval of rimes to reveal as complete clinical manifestation of the aforementioned syndrome, as well as the necessity of multidisciplinary approach in the setting of а general paediatric department in аn emergency hospital. Methods: itpatient's history, clinical presentation, and information from the used diagnostic tools(MRI with contrast of the central nervous system) lead us to the conclusion .This was later on confirmed by the positive results from the anti-aquaporin 4 (AQP4) antibody serology test. Conclusion: APS is a common symptom of NMOSD and is considered a challenge in a differential-diagnostic plan. Gaining an increased awareness of this disease/syndrome, obtaining a detailed patient history, and performing thorough physical examinations are essential if we are to reduce and avoid misdiagnosis.

Keywords: neuromyelitis, devic's disease, hiccup, autoimmune, MRI

Procedia PDF Downloads 22

Authors: Kieren Wilson, Gulnaz Majeed

Abstract:

NHS constitution gives rights to the patient with suspected cancer to be seen by a cancer specialist within 2 weeks of referral. Guys and St Thomas Hospital (GSTT) is one of the largest cancer centres in London. NICE guidelines have provided guidance for health professionals to refer patients appropriately to RAC. In GSTT suspected gynae cancer referrals are mostly by NHS e-Referral Service with some fax, emails as well as paper referrals. The objective of this study was to evaluate compliance with 2-week referral pathway with emphasis on one stop diagnostic service with supporting efficient pathways. A prospective evaluation over 3 months (1 Jan 2017 to 31 Mar 2017) was undertaken. There were 26 clinics, 761 patients were booked in the clinics with a DNA rate of 13% (n=101) hence 606 patients were seen. Majority of referrals were for post menopausal bleeding (PMB) 25% (n=194) followed by cervical, vaginal, vulval reasons 23% (n=179) (abnormal cytology excluded as patients directly referred to colposcopy unit in GSTT), ovarian 7% (n=54) and endometrial 5% (n=41). Women with new or previous established diagnosis of cancer were 24, cervical (n=17), vulva (n=6) and vagina (n=1). Multifocal preinvasive disease vulva (VIN), vagina (VAIN) and cervix (CIN) was confirmed in twenty-six patients 4% (high prevalence in HIV patients). Majority of cervical referrals: PCB (n=14), cervical erosion (n=7), polyps (n=9) and cervical cyst were benign. However, two women with PMB had cervical cancer. Only 2 out of 13 referrals with vaginal concerns had VAIN. One case with non-cervical glandular cytology was confirmed to have endometrial cancer. One stop service based on the diagnostic support of ultrasound, colposcopy and hysteroscopy was achieved in 54% (n=359). Patients were discharged to GP, benign gynaecology, endometriosis, combined vulval/dermatology clinic or gynae oncology. 33% (n=202) required a second visit, 12% (n=70) third visit, 3% (n=19) fourth visit, 1% (n=4) fifth visit and 1% (n=6) sixth visit. Main reasons for follow ups were the unavailability of diagnostic slots, patient choice, need for interpreters, the discussion following gynae MDM review for triage to benign gynae, delay in availability of diagnostic results like histology/MRI/CT. Recommendations following this study are multi disciplinary review of pathways with the availability of additional diagnostic procedure slots to aim for one stop service. Furthermore, establishment of virtual and telephone consultations to reduce follow ups.

Keywords: multifocal disease, post menopausal bleeding, preinvasive disease, rapid access clinic

Procedia PDF Downloads 164

Authors: G. Zakharov, Z. Aslamazashvili, M. Chikhradze, D. Kvaskhvadze, N. Khidasheli, S. Gvazava

Abstract:

Traditional technologies for processing iron-containing industrial waste, including steel-rolling production, are associated with significant energy costs, the long duration of processes, and the need to use complex and expensive equipment. Waste generated during the industrial process negatively affects the environment, but at the same time, it is a valuable raw material and can be used to produce new marketable products. The study of the effectiveness of self-propagating high-temperature synthesis (SHS) methods, which are characterized by the simplicity of the necessary equipment, the purity of the final product, and the high processing speed, is under the wide scientific and practical interest to solve the set problem. The work presents technological aspects of the production of Ferro boron by the method of SHS - metallurgy from iron-containing wastes of rolled production for alloying of cast iron and results of the effect of alloying element on the degree of boron assimilation with liquid cast iron. Features of Fe-B system combustion have been investigated, and the main parameters to control the phase composition of synthesis products have been experimentally established. Effect of overloads on patterns of cast ligatures formation and mechanisms structure formation of SHS products was studied. It has been shown that an increase in the content of hematite Fe₂O₃ in iron-containing waste leads to an increase in the content of phase FeB and, accordingly, the amount of boron in the ligature. Boron content in ligature is within 3-14%, and the phase composition of obtained ligatures consists of Fe₂B and FeB phases. Depending on the initial composition of the wastes, the yield of the end product reaches 91 - 94%, and the extraction of boron is 70 - 88%. Combustion processes of high exothermic mixtures allow to obtain a wide range of boron-containing ligatures from industrial wastes. In view of the relatively low melting point of the obtained SHS-ligature, the positive dynamics of boron absorption by liquid iron is established. According to the obtained data, the degree of absorption of the ligature by alloying gray cast iron at 1450°C is 80-85%. When combined with the treatment of liquid cast iron with magnesium, followed by alloying with the developed ligature, boron losses are reduced by 5-7%. At that, uniform distribution of boron micro-additives in the volume of treated liquid metal is provided. Acknowledgment: This work was supported by Shota Rustaveli Georgian National Science Foundation of Georgia (SRGNSFG) under the GENIE project (grant number № CARYS-19-802).

Keywords: self-propagating high-temperature synthesis, cast iron, industrial waste, ductile iron, structure formation

Procedia PDF Downloads 100

Authors: A. Poukens, I. Sluyts, A. Krings, J. Swartenbroekx, D. Geeroms, J. Poukens

Abstract:

Introduction and Objectives: It has been known for many years that with the administration of intravenous medication, a rather significant part of the planned to be administered infusion solution, the residual volume ( the volume that remains in the IV line and or infusion bag), does not reach the patient and is wasted. This could possibly result in under dosage and diminished therapeutic effect. Despite the important impact on the patient, the reduction of residual volume lacks attention. An optimized and clearly stated protocol concerning the reduction of residual volume in an IV line is necessary for each hospital. As described in my Master’s thesis, acquiring the degree of Master in Hospital Pharmacy, administration of intravenous medication can be optimized by reduction of the residual volume. Herewith effectiveness, user-friendliness, cost efficiency and safety were taken into account. Material and Methods: By usage of a literature study and an online questionnaire sent out to all Flemish hospitals and hospitals in the Netherlands (province Limburg), current flush methods could be mapped out. In laboratory research, possible flush methods aiming to reduce the residual volume were measured. Furthermore, a self-developed experimental method to reduce the residual volume was added to the study. The current flush methods and the self-developed experimental method were compared to each other based on cost efficiency, user-friendliness and safety. Results: There is a major difference between the Flemish and the hospitals in the Netherlands (Province Limburg) concerning the approach and method of flushing IV lines after administration of intravenous medication. The residual volumes were measured and laboratory research showed that if flushing was done minimally 1-time equivalent to the residual volume, 95 percent of glucose would be flushed through. Based on the comparison, it became clear that flushing by use of a pre-filled syringe would be the most cost-efficient, user-friendly and safest method. According to laboratory research, the self-developed experimental method is feasible and has the advantage that the remaining fraction of the medication can be administered to the patient in unchanged concentration without dilution. Furthermore, this technique can be applied regardless of the level of the residual volume. Conclusion and Recommendations: It is recommendable to revise the current infusion systems and flushing methods in most hospitals. Aside from education of the hospital staff and alignment on a uniform substantiated protocol, an optimized and clear policy on the reduction of residual volume is necessary for each hospital. It is recommended to flush all IV lines with rinsing fluid with at least the equivalent volume of the residual volume. Further laboratory and clinical research for the self-developed experimental method are needed before this method can be implemented clinically in a broader setting.

Keywords: intravenous medication, infusion therapy, IV flushing, residual volume

Procedia PDF Downloads 106

Authors: Mahmoud Reza Hosseini

Abstract:

The universe is in a continuous expansion process, resulting in the reduction of its density and temperature. Also, by extrapolating back from its current state, the universe at its early times is studied, known as the big bang theory. According to this theory, moments after creation, the universe was an extremely hot and dense environment. However, its rapid expansion due to nuclear fusion led to a reduction in its temperature and density. This is evidenced through the cosmic microwave background and the universe structure at a large scale. However, extrapolating back further from this early state reaches singularity, which cannot be explained by modern physics, and the big bang theory is no longer valid. In addition, one can expect a nonuniform energy distribution across the universe from a sudden expansion. However, highly accurate measurements reveal an equal temperature mapping across the universe, which is contradictory to the big bang principles. To resolve this issue, it is believed that cosmic inflation occurred at the very early stages of the birth of the universe. According to the cosmic inflation theory, the elements which formed the universe underwent a phase of exponential growth due to the existence of a large cosmological constant. The inflation phase allows the uniform distribution of energy so that an equal maximum temperature can be achieved across the early universe. Also, the evidence of quantum fluctuations of this stage provides a means for studying the types of imperfections the universe would begin with. Although well-established theories such as cosmic inflation and the big bang together provide a comprehensive picture of the early universe and how it evolved into its current state, they are unable to address the singularity paradox at the time of universe creation. Therefore, a practical model capable of describing how the universe was initiated is needed. This research series aims at addressing the singularity issue by introducing a state of energy called a "neutral state," possessing an energy level that is referred to as the "base energy." The governing principles of base energy are discussed in detail in our second paper in the series "A Conceptual Study for Addressing the Singularity of the Emerging Universe," which is discussed in detail. To establish a complete picture, the origin of the base energy should be identified and studied. In this research paper, the mechanism which led to the emergence of this natural state and its corresponding base energy is proposed. In addition, the effect of the base energy in the space-time fabric is discussed. Finally, the possible role of the base energy in quantization and energy exchange is investigated. Therefore, the proposed concept in this research series provides a road map for enhancing our understating of the universe's creation from nothing and its evolution and discusses the possibility of base energy as one of the main building blocks of this universe.

Keywords: big bang, cosmic inflation, birth of universe, energy creation, universe evolution

Procedia PDF Downloads 68

Authors: Osman Adiguzel

Abstract:

Shape memory effect is a peculiar property exhibited by certain alloy systems and based on martensitic transformation, and shape memory properties are closely related to the microstructures of the material. Shape memory effect is linked with martensitic transformation, which is a solid state phase transformation and occurs with the cooperative movement of atoms by means of lattice invariant shears on cooling from high-temperature parent phase. Lattice twinning and detwinning can be considered as elementary processes activated during the transformation. Thermally induced martensite occurs as martensite variants, in self-accommodating manner and consists of lattice twins. Also, this martensite is called the twinned martensite or multivariant martensite. Deformation of shape memory alloys in martensitic state proceeds through a martensite variant reorientation. The martensite variants turn into the reoriented single variants with deformation, and the reorientation process has great importance for the shape memory behavior. Copper based alloys exhibit this property in metastable β- phase region, which has DO3 –type ordered lattice in ternary case at high temperature, and these structures martensiticaly turn into the layered complex structures with lattice twinning mechanism, on cooling from high temperature parent phase region. The twinning occurs as martensite variants with lattice invariant shears in two opposite directions, <110 > -type directions on the {110}- type plane of austenite matrix. Lattice invariant shear is not uniform in copper based ternary alloys and gives rise to the formation of unusual layered structures, like 3R, 9R, or 18R depending on the stacking sequences on the close-packed planes of the ordered lattice. The unit cell and periodicity are completed through 18 atomic layers in case of 18R-structure. On the other hand, the deformed material recovers the original shape on heating above the austenite finish temperature. Meanwhile, the material returns to the twinned martensite structures (thermally induced martensite structure) in one way (irreversible) shape memory effect on cooling below the martensite finish temperature, whereas the material returns to the detwinned martensite structure (deformed martensite) in two-way (reversible) shape memory effect. Shortly one can say that the microstructural mechanisms, responsible for the shape memory effect are the twinning and detwinning processes as well as martensitic transformation. In the present contribution, x-ray diffraction, transmission electron microscopy (TEM) and differential scanning calorimetry (DSC) studies were carried out on two copper-based ternary alloys, CuZnAl, and CuAlMn.

Keywords: shape memory effect, martensitic transformation, twinning and detwinning, layered structures

Procedia PDF Downloads 408

Authors: Mekroud Amel

Abstract:

Introduction The rate of use by the elderly of emergency departments, operating rooms and intensive care units has increased worldwide. Emergency surgery is a context where evaluation is often insufficient, with incomplete information gathering. The aim of this work is to shed light on the frequent use of emergency surgeries by the elderly and their characteristics, as well as on the lack of geriatric assessment scores in the emergency room. Material : Prospective, observational and descriptive, monocentric study. Patients aged 65 and over, admitted for emergency surgery in the operating room, were counted. Emergency operating room including visceral surgery, urology, traumatology and neurosurgery. Parameters studied: Patient characteristics, degree of autonomy, type of surgical pathology, operative management times, preoperative evaluation, postoperative outcome Results : 192 patients were identified over 12 months, from 09.01.2017 to 08.31.2018 Age from 65 to 101 years, 79.81 years +/- 8.38. With predominance of the age group between [65-75 years] 41.1% Female predominance, Sexratio = 0.81 Elderly subjects with total motor autonomy are in the majority at 57.8% Subjects without pathological ATCD represent 12.5% of cases Those who are on only one type of medication or without any treatment are at 36.9% Discussion : The emergency operative care of the elderly patient for a surgical or traumatological pathology is characterized by many specificities linked first to the emergency context, where the evaluation is often insufficient, besides the fact that the elderly patient has particularities requiring reception in centers with experience in the care of this category of patient, or, failing that, a center which uses the minimum of geriatric evaluation scores which are simplified for the emergency departments. In our hospital, we have not yet made this evaluation routine in the emergency room and this delay in the introduction of these scores can be directly attributed to the covid 19 pandemic. Besides the standard preoperative assessment, only 43.2% of patients were assessed in the preoperative period by an anesthesiologist. Traumatological emergencies come first 68.2% followed by visceral emergencies 19.2% (including proctological, urological emergencies), neurosurgical emergencies 7.8% and finally peripheral emergency surgery all acts combined 4.7%. Hospital stay at 9.6 +/- 16.8 days, average operability time of 4.5 +/- 3 days. Death rate at 7.29% Conclusion This work has demonstrated the major impact of emergency surgery, which remains curable for the most part, on the elderly patient despite total motor and cognitive autonomy preoperatively. The improvement of the preoperative evaluation, the reduction of the operating time and enhanced recovery after surgery, with personalized protocols, are the only guarantee for the resumption of preoperative autonomy in these patients.

Keywords: emergency surgery, elderly patients, preoperative geriatric scores, curable emergency surgical pathologies

Procedia PDF Downloads 51

Authors: Mernoosh Abouzari, Shahrokh Sahraei

Abstract:

Electronic government is a way for governments to use new technology that provides people with the necessary facilities for proper access to government information and services, improving the quality of services and providing broad opportunities to participate in democratic processes and institutions. That leads to providing the possibility of easy use of information technology in order to distribute government services to the customer without holidays, which increases people's satisfaction and participation in political and economic activities. The expansion of e-government services and its movement towards intelligentization has the ability to re-establish the relationship between the government and citizens and the elements and components of the government. Electronic government is the result of the use of information and communication technology (ICT), which by implementing it at the government level, in terms of the efficiency and effectiveness of government systems and the way of providing services, tremendous commercial changes are created, which brings people's satisfaction at the wide level will follow. The main level of electronic government services has become objectified today with the presence of artificial intelligence systems, which recent advances in artificial intelligence represent a revolution in the use of machines to support predictive decision-making and Classification of data. With the use of deep learning tools, artificial intelligence can mean a significant improvement in the delivery of services to citizens and uplift the work of public service professionals while also inspiring a new generation of technocrats to enter government. This smart revolution may put aside some functions of the government, change its components, and concepts such as governance, policymaking or democracy will change in front of artificial intelligence technology, and the top-down position in governance may face serious changes, and If governments delay in using artificial intelligence, the balance of power will change and private companies will monopolize everything with their pioneering in this field, and the world order will also depend on rich multinational companies and in fact, Algorithmic systems will become the ruling systems of the world. It can be said that currently, the revolution in information technology and biotechnology has been started by engineers, large economic companies, and scientists who are rarely aware of the political complexities of their decisions and certainly do not represent anyone. Therefore, it seems that if liberalism, nationalism, or any other religion wants to organize the world of 2050, it should not only rationalize the concept of artificial intelligence and complex data algorithm but also mix them in a new and meaningful narrative. Therefore, the changes caused by artificial intelligence in the political and economic order will lead to a major change in the way all countries deal with the phenomenon of digital globalization. In this paper, while debating the role and performance of e-government, we will discuss the efficiency and application of artificial intelligence in e-government, and we will consider the developments resulting from it in the new world and the concepts of governance.

Keywords: electronic government, artificial intelligence, information and communication technology., system

Procedia PDF Downloads 57

Authors: Domenico Panno, Antonino D’amico, Hamed Jafargholi

Abstract:

This paper presents an experimental analysis of the performance of a system for freezing fish products equipped with a modulating vapour injection scroll compressor operating with R448A refrigerant. Freezing is a critical process for the preservation of seafood products, as it influences quality, food safety, and environmental sustainability. The use of a modulating scroll compressor with vapour injection, associated with the R448A refrigerant, is proposed as a solution to optimize the performance of the system, reducing energy consumption and mitigating the environmental impact. The steam injection modulating scroll compressor represents an advanced technology that allows you to adjust the compressor capacity based on the actual cooling needs of the system. Vapour injection allows the optimization of the refrigeration cycle, reducing the evaporation temperature and improving the overall efficiency of the system. The use of R448A refrigerant, with a low global warming potential (GWP), is part of an environmental sustainability perspective, helping to reduce the climate impact of the system. The aim of this research was to evaluate the performance of the system through a series of experiments conducted on a pilot plant for the freezing of fish products. Several operational variables were monitored and recorded, including evaporation temperature, condensation temperature, energy consumption, and freezing time of seafood products. The results of the experimental analysis highlighted the benefits deriving from the use of the modulating vapour injection scroll compressor with the R448A refrigerant. In particular, a significant reduction in energy consumption was recorded compared to conventional systems. The modulating capacity of the compressor made it possible to adapt the cold production to variations in the thermal load, ensuring optimal operation of the system and reducing energy waste. Furthermore, the use of an electronic expansion valve highlighted greater precision in the control of the evaporation temperature, with minimal deviation from the desired set point. This helped ensure better quality of the final product, reducing the risk of damage due to temperature changes and ensuring uniform freezing of the fish products. The freezing time of seafood has been significantly reduced thanks to the configuration of the entire system, allowing for faster production and greater production capacity of the plant. In conclusion, the use of a modulating vapour injection scroll compressor operating with R448A refrigerant has proven effective in improving the performance of a system for freezing fish products. This technology offers an optimal balance between energy efficiency, temperature control, and environmental sustainability, making it an advantageous choice for food industries.

Keywords: freezing, scroll compressor, energy efficiency, vapour injection

Procedia PDF Downloads 12

Authors: Mujahid Muhammad, Paul Kearney, Adel Aneiba

Abstract:

The ability for vehicles to communicate with other vehicles (V2V), the physical (V2I) and network (V2N) infrastructures, pedestrians (V2P), etc. – collectively known as V2X (Vehicle to Everything) – will enable a broad and growing set of applications and services within the intelligent transport domain for improving road safety, alleviate traffic congestion and support autonomous driving. The telecommunication research and industry communities and standardization bodies (notably 3GPP) has finally approved in Release 14, cellular communications connectivity to support V2X communication (known as LTE – V2X). LTE – V2X system will combine simultaneous connectivity across existing LTE network infrastructures via LTE-Uu interface and direct device-to-device (D2D) communications. In order for V2X services to function effectively, a robust security mechanism is needed to ensure legal and safe interaction among authenticated V2X entities in the LTE-based V2X architecture. The characteristics of vehicular networks, and the nature of most V2X applications, which involve human safety makes it significant to protect V2X messages from attacks that can result in catastrophically wrong decisions/actions include ones affecting road safety. Attack vectors include impersonation attacks, modification, masquerading, replay, MiM attacks, and Sybil attacks. In this paper, we focus our attention on LTE-based V2X security and access control mechanisms. The current LTE-A security framework provides its own access authentication scheme, the AKA protocol for mutual authentication and other essential cryptographic operations between UEs and the network. V2N systems can leverage this protocol to achieve mutual authentication between vehicles and the mobile core network. However, this protocol experiences technical challenges, such as high signaling overhead, lack of synchronization, handover delay and potential control plane signaling overloads, as well as privacy preservation issues, which cannot satisfy the adequate security requirements for majority of LTE-based V2X services. This paper examines these challenges and points to possible ways by which they can be addressed. One possible solution, is the implementation of the distributed peer-to-peer LTE security mechanism based on the Bitcoin/Namecoin framework, to allow for security operations with minimal overhead cost, which is desirable for V2X services. The proposed architecture can ensure fast, secure and robust V2X services under LTE network while meeting V2X security requirements.

Keywords: authentication, long term evolution, security, vehicle-to-everything

Procedia PDF Downloads 144

Authors: Kaushal Kishore, Suman Mukhopadhyay, Susovan Das, Manashi Adhikary, Sandip Bhattacharyya

Abstract:

In integrated steel plants, conveyor belts are widely used for transferring raw materials from one location to another. An output pin bush coupling attached with a conveyor transferring iron ore fines and fluxes failed after two years of service life. This led to an operational delay of approximately 15 hours. This study is focused on failure analysis of the coupling and recommending counter-measures to prevent any such failures in the future. Investigation consisted of careful visual observation, checking of operating parameters, stress calculation and analysis, macro and micro-fractography, material characterizations like chemical and metallurgical analysis and tensile and impact testings. The fracture occurred from an unusually sharp double step. There were multiple corrosion pits near the step that aggravated the situation. Inner contact surface of the coupling revealed differential abrasion that created a macroscopic difference in the height of the component. This pointed towards misalignment of the coupling beyond a threshold limit. In addition to these design and installation issues, material of the coupling did not meet the quality standards. These were made up of grey cast iron having graphite morphology intermediate between random distribution (Type A) and rosette pattern (Type B). This manifested as a marked reduction in impact toughness and tensile strength of the component. These findings corroborated well with the brittle mode of fracture that might have occurred during minor impact loading while loading of conveyor belt with raw materials from height. Simulated study was conducted to examine the effect of corrosion pits on tensile and impact toughness of grey cast iron. It was observed that pitting marginally reduced tensile strength and ductility. However, there was marked (up to 45%) reduction in impact toughness due to pitting. Thus, it became evident that failure of the coupling occurred due to combination of factors like inferior material, misalignment, poor step design and corrosion pitting. Recommendation for life enhancement of coupling included the use of tougher SG 500/7 grade, incorporation of proper fillet radius for the step, correction of alignment and application of corrosion resistant organic coating to prevent pitting.

Keywords: brittle fracture, cast iron, coupling, double step, pitting, simulated impact tests

Procedia PDF Downloads 104

Authors: Teruya Goto, Hokuto Chiba, Tatsuhiro Takahashi

Abstract:

Carbon fiber reinforced thermoplastic resin using short carbon fiber has been produced by melt mixing and the improvement of mechanical properties has been frequently reported up to now. One of the most frequently reported enhancement has been seen in carbon fiber / polypropylene (PP) composites by adding small amount of maleic anhydride grafted polypropylene (MA-g-PP) into PP matrix. However, the further enhancement of tensile strength and tensile modules has been expected for lightning the composite more. Our present research aims to improve the mechanical property by using a highly reactive monolayer polymer, which can react with both COOH of carbon fiber surface and maleic anhydride of MA-g-PP in the matrix, on carbon fiber for PP/CF composite. It has been known that oxazoline has much higher reactivity with COOH without catalysts, compared with amine group and alcohol OH group. However, oxazoline group has not been used for the interface. To achieve the purpose, poly-2-vinyl-2-oxazoline (Pvozo), having highly reactivity with COOH and maleic anhydride, has been originally synthesized through radical polymerization using 2-vinyl-2-oxazoline as a monomer, resulting in the Mw around 140,000. Monolayer Pvozo chemically reacted on CF was prepared in 1-methoxy-2-propanol solution of Pvozo by heating at 100oC for 3 hours. After this solution treatment, unreacted Pvozo was completely washed out by methanol, resulting the uniform formation of the monolayer Pvozo on CF. Monolayer Pvozo coated CF was melt mixed by with PP and a small amount of MA-g-PP for the preparation of the composite samples using a batch type melt mixer. With performing the tensile strength tests of the composites, the tensile strength of CF/MA-g-PP/PP showed 40% increase, compared to that of CF/PP. While, that of Pvozo coated CF/MA-g-PP/PP exhibited 80% increase, compared to that of CF/PP. To get deeper insight of the dramatic increase, the weight percentage of chemically grafted polymer based on CF was evaluated by dissolving and removing the matrix polymer by xylene using by thermos gravimetric analysis (TGA). The chemically grafted remained polymer was found to be 0.69wt% in CF/PP, 0.98wt% in CF/MA-g-PP/PP, 1.51wt% in Pvozo coated CF/MA-g-PP/PP, suggesting that monolayer Pvozo contributed to the increase of the grafted polymer amount. In addition, the very strong adhesion by Pvozo was confirmed by observing the fractured cross-sectional surface of the composite by scanning electron micrograph (SEM). As a conclusion, the effectiveness of a highly reactive monolayer Pvozo on CF for the enhancement of the mechanical properties of CF/PP composite was demonstrated, which can be interpreted by the clear evidence of the increase of the grafting polymer on CF.

Keywords: CFRTP, interface, oxazoline, polymer graft, mechanical property

Procedia PDF Downloads 175

Authors: Hendrick Maxil Zárate Rocha, Ricardo da Silva Pereira, Manoel Fernandes Martins Nogueira, Carlos R. Pereira Belchior, Maria Emilia de Lima Tostes

Abstract:

This study investigates experimentally the effects of hydrogen addition in the intake manifold of a diesel generator operating with a 7% biodiesel-diesel oil blend (B7). An experimental apparatus setup was used to conduct performance and emissions tests in a single cylinder, air cooled diesel engine. This setup consisted of a generator set connected to a wirewound resistor load bank that was used to vary engine load. In addition, a flowmeter was used to determine hydrogen volumetric flowrate and a digital anemometer coupled with an air box to measure air flowrate. Furthermore, a digital precision electronic scale was used to measure engine fuel consumption and a gas analyzer was used to determine exhaust gas composition and exhaust gas temperature. A thermopar was installed near the exhaust collection to measure cylinder temperature. In-cylinder pressure was measured using an AVL Indumicro data acquisition system with a piezoelectric pressure sensor. An AVL optical encoder was installed in the crankshaft and synchronized with in-cylinder pressure in real time. The experimental procedure consisted of injecting hydrogen into the engine intake manifold at different mass concentrations of 2,6,8 and 10% of total fuel mass (B7 + hydrogen), which represented energy fractions of 5,15, 20 and 24% of total fuel energy respectively. Due to hydrogen addition, the total amount of fuel energy introduced increased and the generators fuel injection governor prevented any increases of engine speed. Several conclusions can be stated from the test results. A reduction in specific fuel consumption as a function of hydrogen concentration increase was noted. Likewise, carbon dioxide emissions (CO2), carbon monoxide (CO) and unburned hydrocarbons (HC) decreased as hydrogen concentration increased. On the other hand, nitrogen oxides emissions (NOx) increased due to average temperatures inside the cylinder being higher. There was also an increase in peak cylinder pressure and heat release rate inside the cylinder, since the fuel ignition delay was smaller due to hydrogen content increase. All this indicates that hydrogen promotes faster combustion and higher heat release rates and can be an important additive to all kind of fuels used in diesel generators.

Keywords: diesel engine, hydrogen, dual fuel, combustion analysis, performance, emissions

Procedia PDF Downloads 330

Authors: Mahmoud Reza Hosseini

Abstract:

The universe is in a continuous expansion process, resulting in the reduction of its density and temperature. Also, by extrapolating back from its current state, the universe at its early times is studied known as the big bang theory. According to this theory, moments after creation, the universe was an extremely hot and dense environment. However, its rapid expansion due to nuclear fusion led to a reduction in its temperature and density. This is evidenced through the cosmic microwave background and the universe structure at a large scale. However, extrapolating back further from this early state reaches singularity which cannot be explained by modern physics and the big bang theory is no longer valid. In addition, one can expect a nonuniform energy distribution across the universe from a sudden expansion. However, highly accurate measurements reveal an equal temperature mapping across the universe which is contradictory to the big bang principles. To resolve this issue, it is believed that cosmic inflation occurred at the very early stages of the birth of the universe. According to the cosmic inflation theory, the elements which formed the universe underwent a phase of exponential growth due to the existence of a large cosmological constant. The inflation phase allows the uniform distribution of energy so that an equal maximum temperature could be achieved across the early universe. Also, the evidence of quantum fluctuations of this stage provides a means for studying the types of imperfections the universe would begin with. Although well-established theories such as cosmic inflation and the big bang together provide a comprehensive picture of the early universe and how it evolved into its current state, they are unable to address the singularity paradox at the time of universe creation. Therefore, a practical model capable of describing how the universe was initiated is needed. This research series aims at addressing the singularity issue by introducing a state of energy called a “neutral state” possessing an energy level which is referred to as the “base energy”. The governing principles of base energy are discussed in detail in our second paper in the series “A Conceptual Study for Addressing the Singularity of the Emerging Universe” which is discussed in detail. To establish a complete picture, the origin of the base energy should be identified and studied. In this research paper, the mechanism which led to the emergence of this natural state and its corresponding base energy is proposed. In addition, the effect of the base energy in the space-time fabric is discussed. Finally, the possible role of the base energy in quantization and energy exchange is investigated. Therefore, the proposed concept in this research series provides a road map for enhancing our understating of the universe's creation from nothing and its evolution and discusses the possibility of base energy as one of the main building blocks of this universe.

Keywords: big bang, cosmic inflation, birth of universe, energy creation, universe evolution

Procedia PDF Downloads 9

Authors: Laura Kupers, Julie Piérard, Niki Cauberg

Abstract:

The use of exposed concrete (sometimes referred to as architectural concrete), keeps gaining popularity. Exposed concrete has the advantage to combine the structural properties of concrete with an aesthetic finish. However, for a successful aesthetic finish, much attention needs to be paid to the execution (formwork, release agent, curing, weather conditions…), the concrete composition (choice of the raw materials and mix proportions) as well as to its fresh properties. For the latter, a simple on-site pass/fail test could halt the casting of concrete not suitable for architectural concrete and thus avoid expensive repairs later. When architects opt for an exposed concrete, they usually want a smooth, uniform and nearly blemish-free surface. For this choice, a standard ‘construction’ concrete does not suffice. An aesthetic surface finishing requires the concrete to contain a minimum content of fines to minimize the risk of segregation and to allow complete filling of more complex shaped formworks. The concrete may neither be too viscous as this makes it more difficult to compact and it increases the risk of blow holes blemishing the surface. On the other hand, too much bleeding may cause color differences on the concrete surface. An easy pass/fail test, which can be performed on the site just before the casting, could avoid these problems. In case the fresh concrete fails the test, the concrete can be rejected. Only in case the fresh concrete passes the test, the concrete would be cast. The pass/fail tests are intended for a concrete with a consistency class S4. Five tests were selected as possible onsite pass/fail test. Two of these tests already exist: the K-slump test (ASTM C1362) and the Bauer Filter Press Test. The remaining three tests were developed by the BBRI in order to test the segregation resistance of fresh concrete on site: the ‘dynamic sieve stability test’, the ‘inverted cone test’ and an adapted ‘visual stability index’ (VSI) for the slump and flow test. These tests were inspired by existing tests for self-compacting concrete, for which the segregation resistance is of great importance. The suitability of the fresh concrete mixtures was also tested by means of a laboratory reference test (resistance to segregation) and by visual inspection (blow holes, structure…) of small test walls. More than fifteen concrete mixtures of different quality were tested. The results of the pass/fail tests were compared with the results of this laboratory reference test and the test walls. The preliminary laboratory results indicate that concrete mixtures ‘suitable’ for placing as exposed concrete (containing sufficient fines, a balanced grading curve etc.) can be distinguished from ‘inferior’ concrete mixtures. Additional laboratory tests, as well as tests on site, will be conducted to confirm these preliminary results and to set appropriate pass/fail values.

Keywords: exposed concrete, testing fresh concrete, segregation resistance, bleeding, consistency

Procedia PDF Downloads 402

Authors: Dangut Maren David, Skaf Zakwan

Abstract:

Adequate monitoring of vehicle component in other to obtain high uptime is the goal of predictive maintenance, the major challenge faced by businesses in industries is the significant cost associated with a delay in service delivery due to system downtime. Most of those businesses are interested in predicting those problems and proactively prevent them in advance before it occurs, which is the core advantage of Prognostic Health Management (PHM) application. The recent emergence of industry 4.0 or industrial internet of things (IIoT) has led to the need for monitoring systems activities and enhancing system-to-system or component-to- component interactions, this has resulted to a large generation of data known as big data. Analysis of big data represents an increasingly important, however, due to complexity inherently in the dataset such as imbalance classification problems, it becomes extremely difficult to build a model with accurate high precision. Data-driven predictive modeling for condition-based maintenance (CBM) has recently drowned research interest with growing attention to both academics and industries. The large data generated from industrial process inherently comes with a different degree of complexity which posed a challenge for analytics. Thus, imbalance classification problem exists perversely in industrial datasets which can affect the performance of learning algorithms yielding to poor classifier accuracy in model development. Misclassification of faults can result in unplanned breakdown leading economic loss. In this paper, an advanced approach for handling imbalance classification problem is proposed and then a prognostic model for predicting aircraft component replacement is developed to predict component replacement in advanced by exploring aircraft historical data, the approached is based on hybrid ensemble-based method which improves the prediction of the minority class during learning, we also investigate the impact of our approach on multiclass imbalance problem. We validate the feasibility and effectiveness in terms of the performance of our approach using real-world aircraft operation and maintenance datasets, which spans over 7 years. Our approach shows better performance compared to other similar approaches. We also validate our approach strength for handling multiclass imbalanced dataset, our results also show good performance compared to other based classifiers.

Keywords: prognostics, data-driven, imbalance classification, deep learning

Procedia PDF Downloads 150

Authors: Amit Sarkar, Jayanta K. Mahato, Tushar Bhattacharya, Amrita Kundu, P. C. Chakraborti

Abstract:

With increasing the demand for safety and fuel efficiency of automobiles, automotive manufacturers are looking for light weight, high strength steel with excellent formability and corrosion resistance. Dual-phase steel is finding applications in automotive sectors, because of its high strength, good formability, and high corrosion resistance. During service automotive components suffer from environmental attack and thereby gradual degradation of the components occurs reducing the service life of the components. The objective of the present investigation is to assess the effect of deformation on corrosion behaviour of DP590 grade dual phase steel which is used in automotive industries. The material was received from TATA Steel Jamshedpur, India in the form of 1 mm thick sheet. Tensile properties of the steel at strain rate of 10-3 sec-1: 0.2 % Yield Stress is 382 MPa, Ultimate Tensile Strength is 629 MPa, Uniform Strain is 16.30% and Ductility is 29%. Rectangular strips of 100x10x1 mm were machined keeping the long axis of the strips parallel to rolling direction of the sheet. These strips were longitudinally deformed at a strain rate at 10-3 sec-1 to a different percentage of strain, e.g. 2.5, 5, 7.5,10 and 12.5%, and then slowly unloaded. Small specimens were extracted from the mid region of the unclamped portion of these deformed strips. These small specimens were metallographic polished, and corrosion behaviour has been studied by potentiodynamic polarization, electrochemical impedance spectra, and cyclic polarization and potentiostatic tests. Present results show that among three different environments, the 3.5 pct NaCl solution is most aggressive in case of DP 590 dual-phase steel. It is observed that with the increase in the amount of deformation, corrosion rate increases. With deformation, the stored energy increases and leads to enhanced corrosion rate. Cyclic polarization results revealed highly deformed specimen are more prone to pitting corrosion as compared to the condition when amount of deformation is less. It is also observed that stability of the passive layer decreases with the amount of deformation. With the increase of deformation, current density increases in a passive zone and passive zone is also decreased. From Electrochemical impedance spectroscopy study it is found that with increasing amount of deformation polarization resistance (Rp) decreases. EBSD results showed that average geometrically necessary dislocation density increases with increasing strain which in term increased galvanic corrosion as dislocation areas act as the less noble metal.

Keywords: dual phase 590 steel, prestrain, potentiodynamic polarization, cyclic polarization, electrochemical impedance spectra

Procedia PDF Downloads 404

Authors: W. A. Nalaka Wijesooriya

Abstract:

The increasing paddy production, stabilization of domestic rice consumption and the increasing dynamism of rice processing and domestic markets call for a rethinking of the general direction of the rice milling industry in Sri Lanka. The main purpose of the study was to explore levels of concentration in rice milling industry in Polonnaruwa and Hambanthota which are the major hubs of the country for rice milling. Concentration indices reveal that the rice milling industry in Polonnaruwa operates weak oligopsony and is highly competitive in Hambanthota. According to the actual quantity of paddy milling per day, 47 % is less than 8Mt/Day, while 34 % is 8-20 Mt/day, and the rest (19%) is greater than 20 Mt/day. In Hambanthota, nearly 50% of the mills belong to the range of 8-20 Mt/day. Lack of experience of the milling industry, poor knowledge on milling technology, lack of capital and finding an output market are the major entry barriers to the industry. Major problems faced by all the rice millers are the lack of a uniform electricity supply and low quality paddy. Many of the millers emphasized that the rice ceiling price is a constraint to produce quality rice. More than 80% of the millers in Polonnaruwa which is the major parboiling rice producing area have mechanical dryers. Nearly 22% millers have modern machineries like color sorters, water jet polishers. Major paddy purchasing method of large scale millers in Polonnaruwa is through brokers. In Hambanthota major channel is miller purchasing from paddy farmers. Millers in both districts have major rice selling markets in Colombo and suburbs. Huge variation can be observed in the amount of pledge (for paddy storage) loans. There is a strong relationship among the storage ability, credit affordability and the scale of operation of rice millers. The inter annual price fluctuation ranged 30%-35%. Analysis of market margins by using series of secondary data shows that farmers’ share on rice consumer price is stable or slightly increases in both districts. In Hambanthota a greater share goes to the farmer. Only four mills which have obtained the Good Manufacturing Practices (GMP) certification from Sri Lanka Standards Institution can be found. All those millers are small quantity rice exporters. Priority should be given for the Small and medium scale millers in distribution of storage paddy of PMB during the off season. The industry needs a proper rice grading system, and it is recommended to introduce a ceiling price based on graded rice according to the standards. Both husk and rice bran were underutilized. Encouraging investment for establishing rice oil manufacturing plant in Polonnaruwa area is highly recommended. The current taxation procedure needs to be restructured in order to ensure the sustainability of the industry.

Keywords: conduct, performance, structure (SCP), rice millers

Procedia PDF Downloads 303

Authors: El Khaddam Safaa, Soulaymani Abdelmajid, Mokhtari Abdelghani, Ouammi Lahcen, Rachida Soulaymani-Beincheikh

Abstract:

The poisonings represent a problem of health in the world and Morocco, The exact dimensions of this phenomenon are still poorly recorded that we see the lack of exhaustive statistical data. The objective of this retrospective study of a series of cases of the poisonings declared at the level of the region of Tadla-Azilal and collected by the Moroccan Poison Control and Pharmacovigilance Center. An epidemiological profile of the poisonings was to raise, to determine the risk factors influencing the vital preview of the poisoned And to follow the evolution of the incidence, the lethality, and the mortality. During the period of study, we collected and analyzed 9303 cases of poisonings by different incriminated toxic products with the exception of the scorpion poisonings. These poisonings drove to 99 deaths. The epidemiological profile which we raised, showed that the poisoned were of any age with an average of 24.62±16.61 years, The sex-ratio (woman/man) was 1.36 in favor of the women. The difference between both sexes is highly significant (χ2 = 210.5; p<0,001). Most of the poisoned which declared to be of urban origin (60.5 %) (χ2=210.5; p<0,001). Carbon monoxide was the most incriminated among the cases of poisonings (24.15 %), them putting in head, followed by some pesticides and farm produces (21.44 %) and food (19.95 %). The analysis of the risk factors showed that the grown-up patients whose age is between 20 and 74 years have twice more risk of evolving towards the death (RR=1,57; IC95 % = 1,03-2,38) than the other age brackets, so the male genital organ was the most exposed (explained) to the death that the female genital organ (RR=1,59; IC95 % = 1,07-2,38) The patients of rural origin had presented 5 times more risk (RR=4,713; IC95 % = 2,543-8,742). Poisoned by the mineral products had presented the maximum of risk on the vital preview death (RR=23,19, IC95 % = 2,39-224,1). The poisonings by pesticides produce a risk of 9 (RR=9,31; IC95 % = 6,10-14,18). The incidence was 3,3 cases of 10000 inhabitants, and the mortality was 0,004 cases of 1000 inhabitants (that is 4 cases by 1000 000 inhabitants). The rate of lethality registered annually was 10.6 %. The evolution of the indicators of health according to the years showed that the rate of statement measured by the incidence increased by a significant way. We also noted an improvement in the coverage which (who) ended up with a decrease in the rate of the lethality and the mortality during last years. The fight anti-toxic is a work of length time. He asks for a lot of work various levels. It is necessary to attack the delay accumulated by our country on the various legal, institutional and technical aspects. The ideal solution is to develop and to set up a national strategy.

Keywords: epidemiology, poisoning, risk factors, indicators of health, Tadla-Azilal grated by anti-toxic fight

Procedia PDF Downloads 340