21 research outputs found
The Performance of Cooperative MIMO Scheme under Slow Fading Channel based on Fountain Code
Nowadays, the video calling, video on demand (VOD) and more services are desired for users. These services generate large traffic which requires special techniques for transmission without outages or failure during transmission operation. Fountain Code is the newest method in the encoding theory and it is handle designed to large data. Besides, modern MIMO channel gives higher capacity than traditional channel (SISO channel). This paper looks out of the performance of Fountain Code on MIMO Scheme under Slow Fading Channel. The results show the performance is the best on MIMO (DF). In addition, the performance increases by increasing in the number of receiver antennas.
Keywords: Fountain Code, Luby Transform, Cooperative MIMO, Slow Fading, Bit Error Rate, Decode and Forward (DF)
Low Cost Microcontroller Based TIC TAC TOE Game.
TIC TAC TOE is a commonly traditional game in Yemen, which consists of two players. One of the player chooses a cell of the game and puts an X mark in the chosen cell while the second player chooses another cell and puts an O mark in this second cell. The purpose of the paper is to transport this commonly traditional game to modern electronic game to get along with modern electronic world. The modern electronic game is important to countryside children’s, so that they can play the game safely without incurring diseases. It also aims to offer children an opportunity to deal with cheap modern techniques. The game designed in this paper is based on the microcontroller (PIC16f877A)
Risk factors for periodontal diseases among Yemeni type II diabetic patients. A case-control study.
Background: Chronic periodontal diseases are one of diabetes mellitus complications. The present study aims to compare the periodontal status of type II diabetic patients to a control group and assess the role of risk factors in both groups. Materials and methods: A case-control study was conducted of 270 individuals (132 type II diabetics and 138 non-diabetics). Full mouth periodontal examination including plaque index, gingival bleeding, gingival recession, clinical attachment loss (CAL), tooth mobility, furcation involvement and the number of missing teeth. The case group was subdivided according to glycosylated hemoglobin (HbA1c) status (poorly controlled HbA1c >8 and well controlled HbA1c ≤8) Likewise, the duration of diabetes mellitus as short or long duration (DM ≤10 or >10). The diabetic group was also subdivided according to smoking and Khat chewing habits. Result: The severity of periodontal disease among type II diabetic patients were significantly higher compared to the control group regarding the plaque index 2.6 (1.6-4.3), bleeding on probing 3.5 (2.3-13.0), gingival recession 2.0 (1.2-3.4), furcation involvement 4.0 (2.3-6.7), clinical attachment loss 5.7 (3.1-10.5), tooth mobility 2.0 (1.2-3.4), and number of missing teeth 4.4 (2.3-8.5). In addition, poorly controlled type II DM and long duration had higher CAL and number of missing teeth than well-controlled DM and short duration. No significant differences were found between smokers/nonsmokers and Khat chewers/non-chewers among the diabetic group. Conclusion: Type II diabetic patients have severe periodontal destruction and tooth loss compared to non-diabetic people and there were no differences within the diabetic group in regards to smoking and Khat chewing habits
Tongue lesions and anomalies in a sample of Yemeni dental patients: A cross-sectional study.
Background: Tongue examination helps considerably in diagnosing the underlying health state of the patient, especially in the cases of chronic diseases. The aim of this study is to determine the prevalence and association of tongue lesions with risk factors among Yemeni dental patients. Materials and methods: An oral medicine specialist examined all 713 patients attending the dental polyclinics at the University of Sciences and Technology (Sana’a, Yemen). The examination sheet was designed to include information related to patient characteristics, medical history, dental history, habits, and tongue lesions. Results: The prevalence of tongue lesions among the examined participants was 76.5%. The prevalence rate was 83.4% for males and 69.2% for females. Fissured tongue was the most common condition. Logistic regression analysis indicated that older age (p<0.001), gender (p=0.007), khat chewing (p<0.001), and smoking (p=0.001) were associated with fissured tongue; gender (p<0.001), khat chewing (p<0.001), and smoking (p<0.001) were associated with hairy tongue; and older age (p<0.001), khat chewing (p=0.001), and smoking (p=.021) were associated with coated tongue. Conclusion: The prevalence of tongue lesions among this sample of Yemeni population was 76.5%; fissured tongue and hairy tongue were the most prevalent lesions. Khat chewing, smoking, and older age were the associated risk factors for many of studied lesions and anomalies
Prevalencia de dientes impactados entre una muestra de población yemení y su asociación con el sexo y la edad.
Aim: the aim of the study was to assess the prevalence of impacted teeth and its association with sex and age among a sample of the Yemeni population. Materials and Methods: A cross sectional study design was employed. The study included 999 radiographical records of patients who had panoramic X- rays previously done. All radiographs were assessed for the number and type of impacted teeth, pathology-associated impaction, sex, age and location (mandible and/or maxilla). The collected data was analyzed using SPSS®version21 software. Results: The study sample comprised digital panoramic radiographs of Yemeni patients aged 17 to 54 years (mean 26.6 years). The present study found 542 patients (54.3%) presented with at least one impacted tooth. The 17 to 25 years age group of the study sample had the highest prevalence of tooth impaction (28.6%). Only 10 (1.0%) case presented pathologies associated with the impacted teeth. There was a significant difference in the number of male 203 (20.3%) and female 339 (33.9%) patients with impacted teeth (p=0.031). Impacted teeth occurred slightly more often in the mandible (42.8%) compared to the maxilla (42.4%). Conclusion: The prevalence of impacted teeth among a sample of Yemeni population was high. Third molars and canines were the most common impacted teeth. The prevalence of impacted teeth in females was higher than in males and it was higher in the mandible than in the maxilla, with the younger patients with a higher prevalence of impaction.Objetivo: el objetivo del estudio fue evaluar la prevalencia de dientes impactados y su asociación con el sexo y la edad en una muestra de la población yemení. Material y Métodos: se empleó un diseño de estudio transversal. El estudio incluyó 999 registros radiográficos de pacientes con radiografías panorámicas realizadas previamente. Todas las radiografías fueron evaluadas en relación al número y tipo de dientes impactados, patología asociada a la impactación, sexo, edad y ubicación (mandíbula y/o maxilar). Los datos recopilados se analizaron utilizando el software SPSS® version 21. Resultados: La muestra del estudio comprendió radiografías panorámicas digitales de pacientes yemeníes entre 17 a 54 años (media 26,6 años). El presente estudio encontró que 542 pacientes (54,3%) presentaron al menos un diente impactado. El grupo de edad de 17 a 25 años de la muestra de estudio tuvo la mayor prevalencia de impactación dental (28,6%). Solo 10 casos (1,0%) presentaron patologías asociadas a los dientes impactados. Hubo una diferencia significativa en el número de pacientes masculinos 203 (20.3%) y femeninos 339 (33.9%) con dientes impactados (p=0.031). Los dientes impactados ocurrieron con un poco más de frecuencia en la mandíbula (42.8%) en comparación con el maxilar (42.4%). Conclusión: La prevalencia de dientes impactados entre una muestra de población yemení fue alta. Los terceros molares y caninos fueron los dientes más comúnmente impactados. La prevalencia de dientes impactados en las mujeres fue mayor que en los hombres y fue mayor en la mandíbula que en el maxilar, y los pacientes más jóvenes mostraron una mayor prevalencia de impactación
Management of temporomandibular joint ankylosis in Yemeni children by metatarsal bone grafts.
Aim: This study aimed to evaluate temporomandibular joint reconstruction in Yemeni children with metatarsal bone graft after release of ankylosis. Methodology: Ten patients ≤12 years of age, comprising eight unilateral and two bilaterally TMJ ankylosis, were selected for this study. These patients underwent reconstruction with 10 non-vascularized metatarsal grafts. The reconstructed joints were then followed for an average of 1 year. Measures of opening, symmetry, and clinical symptoms relating to the reconstructed joints were assessed. Results: Mean pre-operative interincisal aperture was 8.2mm, and immediate post-operative aperture 23.4mm. At the end of the follow-up period, acceptable results were achieved in 8 out of 10 cases, with adequate mouth opening of 35.6mm in 8 out of 10 patients and overall interincisal aperture of 30.3mm. Re-ankylosis occurred in two bilaterally-treated patients at the end of follow-up. Subjectively, 80% of the patients rated their function as satisfactory and were able to occlude and masticate without any difficulty. Conclusion: Reconstruction of TMJ after release of ankylosis utilizing metatarsal bone graft shows a satisfactory interincisal aperture in 80% of patients
Drug Prescription Knowledge and Practices among Dental Students and Interns Enrolled in Selected Yemeni Universities
Objective: To assess the drug prescription knowledge among dental students and interns in public and private Yemeni universities.
Methods: A descriptive, observational study of drug prescription knowledge and practices was conducted through the distribution of self-administrated questionnaires to a total of 464 dental students and interns enrolled in four universities in Yemen in 2015. The study investigated the factors to be considered before drug prescribing, indications for prescribing antibiotics in dental situations, common antibiotics and analgesics prescribed, difficulties in writing a prescription and knowledge of the World Health Organization’s Guide to Good Prescribing. Findings were presented as descriptive statistics of frequencies and percentages, and differences and associations were tested at P-values <0.05.
Results: The majority of respondents were females (65.9%; 304/464), being enrolled in public universities (54.1%; 251/464) and from the fifth level of study (54.9%; 251/464). The mean respondents’ age was 23.0 ±1.3 years (range: 22–32). Presence of systemic diseases (75.0%), pregnancy status (72.2%) and presence of allergies (68.8%) were the factors most frequently considered by the respondents prior to drug prescribing. On the other hand, presence of abscesses was the most frequent reason for prescribing antibiotics (36.6%). Amoxicillin was the most frequently prescribed antibiotic (74.1%), while paracetamol (58.2%) and ibuprofen (47.0%) were the most frequently prescribed analgesics. Not knowing the brand names of prescribed drugs and wrongly filled prescriptions were the most frequent errors in writing prescriptions, being reported by 79.3% and 55.3% of respondents, respectively. Regarding the factors associated with common prescribing errors, female students had significantly more errors than their male counterparts regarding the posology and knowledge of brand names. In addition, fifth-level students reported significantly fewer errors in writing a drug prescription than fourth-level students, and the interns showed fewer errors than their undergraduate colleagues. Moreover, students from public universities reported significantly more errors in knowing brand names and duration of treatment than private university students.
Conclusions: Dental students enrolled at the fourth and fifth levels as well as in the internship year of dentistry have insufficient knowledge and skills in prescribing drugs used in the dental field because of the perceived gaps in clinical pharmacology courses during their study. Revising the timing and content of pharmacology courses in dental curricula is required in light of the positive aspects of those from the dental faculties worldwide, emphasizing on drug prescribing skills and preparing dental students well before the clinical levels of the study program
An efficient scheme for interference mitigation in 6G-IoT wireless networks
The Internet of Things (IoT) is the fourth technological revolution in the global information industry after computers, the Internet, and mobile communication networks. It combines radio-frequency identification devices, infrared sensors, global positioning systems, and various other technologies. Information sensing equipment is connected via the Internet, thus forming a vast network. When these physical devices are connected to the Internet, the user terminal can be extended and expanded to exchange information, communicate with anything, and carry out identification, positioning, tracking, monitoring, and triggering of corresponding events on each device in the network. In real life, the IoT has a wide range of applications, covering many fields, such as smart homes, smart logistics, fine agriculture and animal husbandry, national defense, and military. One of the most significant factors in wireless channels is interference, which degrades the system performance. Although the existing QR decomposition-based signal detection method is an emerging topic because of its low complexity, it does not solve the problem of poor detection performance. Therefore, this study proposes a maximum-likelihood-based QR decomposition algorithm. The main idea is to estimate the initial level of detection using the maximum likelihood principle, and then the other layer is detected using a reliable decision. The optimal candidate is selected from the feedback by deploying the candidate points in an unreliable scenario. Simulation results show that the proposed algorithm effectively reduces the interference and propagation error compared with the algorithms reported in the literature
Oral health practices and self-reported adverse effects of E-cigarette use among dental students in 11 countries: an online survey
Objectives: E-cigarette use has become popular, particularly among the youth. Its use is associated with harmful general and oral health consequences. This survey aimed to assess self-reported oral hygiene practices, oral and general health events, and changes in physiological functions (including physical status, smell, taste, breathing, appetite, etc.) due to E-cigarette use among dental students. Methods: This online, multicounty survey involved undergraduate dental students from 20 dental schools across 11 different countries. The questionnaire included demographic characteristics, E-cigarette practices, self-reported complaints, and associated physiological changes due to E-cigarette smoking. Data were descriptively presented as frequencies and percentages. A Chi-square test was used to assess the potential associations between the study group and sub-groups with the different factors. Statistical analysis was performed using SPSS at P < 0.05. Results: Most respondents reported regular brushing of their teeth, whereas only 70% used additional oral hygiene aids. Reported frequencies of complaints ranged from as low as 3.3% for tongue inflammation to as high as 53.3% for headache, with significant differences between E-cigarette users and non-users. Compared to non-smokers, E-cigarette users reported significantly higher prevalence of dry mouth (33.1% vs. 23.4%; P < 0.001), black tongue (5.9% vs. 2.8%; P = 0.002), and heart palpitation (26.3%% vs. 22.8%; P = 0.001). Although two-thirds of the sample reported no change in their physiological functions, E-cigarette users reported significant improvement in their physiological functions compared to never smokers or tobacco users. Conclusion: Dental students showed good oral hygiene practices, but E-cigarette users showed a higher prevalence of health complications.Dental Biomaterials Research Chair, Deanship of Scientific Research, King Saud University. The funder has no role in the design of the study as well as in the methodology, analysis, and interpretation of the data
Knowledge, beliefs, attitude, and practices of E-cigarette use among dental students: A multinational survey
E-cigarette use is a trend worldwide nowadays with mounting evidence on associated morbidities and mortality. Dentists can modify the smoking behaviors of their patients. This study aimed to explore the knowledge, beliefs, attitude, and practice of E-cigarette use among dental students. This multinational, cross-sectional, questionnaire-based study recruited undergraduate dental students from 20 dental schools in 11 countries. The outcome variable was current smoking status (non-smoker, E-cigarette user only, tobacco cigarette smoker only, dual user). The explanatory variables were country of residence, sex, age, marital status, and educational level. Multiple linear regression analysis was performed to explore the explanatory variables associated with E-cigarette smoking. Of the 5697 study participants, 5156 (90.8%) had heard about E-cigarette, and social media was the most reported source of information for 33.2% of the participants. For the 5676 current users of E-cigarette and/or tobacco smoking, 4.5% use E-cigarette, and 4.6% were dual users. There were significant associations between knowledge and country (P< 0.05), educational level (B = 0.12; 95% CI: 0.02, 0.21; P = 0.016) and smoking status (P< 0.05). The country of residence (P< 0.05) and smoking status (P< 0.05) were the only statistically significant factors associated with current smoking status. Similarly, there were statistically significant associations between attitude and country (P< 0.05 for one country only compared to the reference) and history of previous E-cigarette exposure (B = -0.52; 95% CI: -0.91, -0.13; P = 0.009). Also, the practice of E-cigarettes was significantly associated with country (P< 0.05 for two countries only compared to the reference) and gender (B = -0.33; 95% CI: -0.52, -0.13; P = 0.001). The knowledge of dental students about E-cigarette was unsatisfactory, yet their beliefs and attitudes were acceptable. Topics about E-cigarette should be implemented in the dental curriculum.Deanship of Scientific Research, King Saud University, for funding through the Vice Deanship of Scientific Research for Research Chairs. Qatar National Library for the open access funding