132 research outputs found
Sampled-Data Sliding Mode Control Design of Single- Link Flexible Joint Robotic Manipulator
International audienceIn this paper, we have designed a sampled data control law for the single-link flexible joint robotic manipulator using two different approaches. First, we have designed the sampled-data sliding mode control (SMC) based on the continuous time system. In the second approach, we have obtained the approximate discrete model of the system and then designed discrete sliding mode control based on this approximate system. Simulation results have been obtained and a performance comparison has been presented for both techniques
Role of Dopamine Receptors in Olfaction Learning Success
Several biogenic amines neurotransmitters are involved in various social behaviors, including olfaction learning behavior, cast differentiation, generation overlapping and sociability in honeybees. One of the brain\u27s primary functions is remembering and learning the information related to food and odor. Dopamine (DA) is an important signaling molecule derived from the amino acid tyrosine. It is also known as a key neurohormone, neuromodulator and neurotransmitter in vertebrates as well as invertebrates and several studies indicated their important role in olfaction success, rewarding prediction, learning, memory, motor functions, sleep and arousal, aggression, and numerous other behaviors. Evidence suggests that DA plays several roles in honeybees, especially in olfaction success. Three DA receptors, AmDOP1, AmDOP2 and AmDOP3, have been characterized and clones. In this chapter, I focus on the regulation and involvement of the DA in olfactory learning behavior, locomotor function, motivation, and happy memories. This chapter represents an attempt to associate the role of dopamine receptors in olfaction success in honeybees
Conservative management of invasive cervical resorption: a case Report
Abstract
Invasive cervical resorption is a condition that affects the root surface area below the epithelial attachment. Multiple treatment modalities are advocated, involving exposure of the invasive defect, removal of the granulation tissue and sealing with various restorative materials. This report demonstrates conservative treatment of a patient presenting with peri-apical periodontitis in upper right central and lateral incisors, along with Class II invasive resorption defect cervically on the mesial aspect of the central incisor, as a result of trauma. As the patient was not willing for any surgical intervention, only ortho-grade root canal treatment was carried out in both teeth, with Calcium hydroxide as intra-canal medicament. At three year follow-up, the patient remains asymptomatic demonstrating radiographic evidence of infilling of defect with bone-like tissue. Within the limitations of this report, it was seen that this conservative method for halting the progression of invasive cervical resorption could be under taken in patients who are un-willing for surgical intervention or in whom surgery is contra-indicate
Inculcating research curriculum in operative dentistry - endodontics residency programme: Experience and outcomes
Incorporating research education and training in residency curriculum increases the understanding of evidence-based decision-making among doctors in training. Evidence suggests that the addition of research is linearly associated with improvement in clinical competence, and encourages the residents to shape their career as clinical investigators. The current paper was planned to share the experience of adding research into the core curriculum of Operative Dentistry-Endodontics residency programme at a tertiary care university hospital, and to evaluate the outcome achieved with that change
Gender-specific psychological and social impact of COVID-19 in Pakistan
Background: COVID-19 has rapidly spread across the world. Women may be especially vulnerable to depression and anxiety as a result of the pandemic.Aims: This study attempted to assess how gender affects risk perceptions, anxiety levels and behavioural responses to the COVID-19 pandemic in Pakistan, to recommend gender-responsive health policies.Methods: A cross-sectional online survey was conducted. Participants were asked to complete a sociodemographic data form, the Hospital Anxiety and Depression Scale, and questions on their risk perceptions, preventive behaviour and information exposure. Multiple logistic regression analysis was used to assess the effects of factors such as age, gender and household income on anxiety levels.Results: Of the 1391 respondents, 478 were women and 913 were men. Women considered their chances of survival to be relatively lower than men (59% v. 73%). They were also more anxious (62% v. 50%) and more likely to adopt precautionary behaviour, such as avoiding going to the hospital (78% v. 71%), not going to work (72% v. 57%) and using disinfectants (93% v. 86%). Men were more likely to trust friends, family and social media as reliable sources of COVID-19 information, whereas women were more likely to trust doctors.Conclusions: Women experience a disproportionate burden of the psychological and social impact of the pandemic compared with men. Involving doctors in healthcare communication targeting women might prove effective. Social media and radio programmes may be effective in disseminating COVID-19-related information to men
Golden Proportion in Visual Dental Smile in Pakistani Population: A Pilot Study
Uvod: Oduvijek se raspravljalo o tome što čini dobru dentalnu estetiku, s obzirom na to da ona može varirati od osobe do osobe, ovisno o njezinu iskustvu i društvenom okružju. Zato se “zlatni omjer” smatra važnim kako bi se postigla estetika i skladan osmijeh. Svrha: Istraživanjem se željelo postići sljedeće: odrediti prevalenciju “zlatnog omjera” vidljive širine na odabranom uzorku pakistanske populacije; ispitati ima li spolnih razlika u stvarnim širinama gornjih prednjih zuba; ustanoviti korisnost Levinove FI zubne ljestvice kao prediktora “zlatnog omjera”. Ispitanici i postupci: Od stotinu pacijenata odabranih neprobabilističkim uzorkovanjem, samo je njih 44 bilo uključeno u istraživanje. Za mjerenje zuba stručnjaci su se koristili zubnim modelima odabranih ispitanika. Stvarna širina (meziodistalna) mjerila se pomičnom mjerkom, a vidljiva (širina maksilarnih frontalnih zuba gledano sprijeda) ljestvicom i mjerkom. Predicirana širina izračunavala se korištenjem “zlatnog omjera” za gornji bočni sjekutić i gornji očnjak. Nakon toga su podaci bili statistički analizirani (deskriptivna statistika, Pearsonov koeficijent korelacije, t-test). Rezultati: Šezdeset i tri posto (63,6 %) uzorka (22 žene i 6 muškaraca) odgovaralo je ljestvici “zlatnog omjera” kad je riječ o vidljivoj širini gornjih prednjih zuba. Gledano sprijeda, vidljiva širina gornjih bočnih sjekutića iznosila je 75 posto stvarne širine središnjih sjekutića (središnji sjekutić bio je referentni zub te je zato korištena stvarna širina), a vidljiva širina očnjaka bila je 61,3 posto (gotovo “zlatni postotak”) vidljive širine bočnih sjekutića. Nije bilo veće spolne razlike u stvarnoj širini gornjih središnjih i bočnih sjekutića te očnjaka. Zaključak: Z ubna ljestvica FI može biti korisna i dobra početna točka za predikciju “zlatnog omjera” kod 63 posto pakistanske populacije. Ipak, taj se omjer ne bi se trebao smatrati odlučujućim čimbenikom dentalne privlačnosti. To bi prije trebao biti raspon nego jedna vrijednost.Introduction: It has always been argued as to what constitutes good dental esthetics, as it can vary from person to person depending on personal experiences and social surroundings. Golden proportion has been stated to be an important tool for achieving esthetics and harmony in smile. Objectives: The aim of this study was to find out prevalence of golden proportion of the apparent width in a selected sample of Pakistani population, to examine if there is gender difference considering actual maxillary frontal teeth widths, to determine the usefulness of Levin’s Phi Dental Grid as a predictor of golden proportion. Material and Method: From one hundred patients evaluated using non-probability sampling, only 44 were included in the study. Dental casts of the selected individuals were used for teeth measurement. The actual width (measured mesiodistal width) was measured using vernier caliper, the apparent width (width of the maxillary frontal teeth when viewed from the front) was measured using the grid and the caliper, and the predicted width was calculated using the Golden proportion for the maxillary lateral incisor and the maxillary canine. Data was subjected to statistical analysis (descriptive statistics, Pearson’s coeficient of correlation, t-test). Results: Sixty three percent of the sample (22 females and 6 males)
fitted the scale of golden proportion considering the apparent width of the maxillary frontal teeth. When viewed from the front, maxillary lateral incisor’s apparent width was 75% of the central incisor’s actual width (central incisor was reference tooth therefore actual width was used) and the canine’s apparent width was 61.3% (almost golden percentage) of the lateral incisor’s apparent width. There was no significant gender difference for the actual widths of the maxillary central incisors, lateral incisors and canines. Conclusion: Phi Dental Grid can be useful tool and a good starting point to predict golden proportion in 63% of the Pakistani population. However, golden proportion should not be considered as a decisive factor of determining dental attractiveness. It should be a range rather then a single value
Frequency of intraoperative hypotension after the induction of anesthesia in hypertensive patients with preoperative angiotensin-converting enzyme inhibitors
Introduction: The renin-angiotensin-aldosterone system (RAAS) is an important target in the treatment of hypertension. Angiotensin-converting enzyme (ACE) inhibitors block the conversion of angiotensin I to angiotensin II. ACE inhibitors not only treat hypertension but also decrease morbidity and mortality in heart failure patients and in patients with acute myocardial infarction. The discontinuation of ACE inhibitors before the surgery is still controversial. To assess the current magnitude of the problem in our population, we aimed to conduct this study, which evaluated the frequency of intraoperative hypotension after the induction of anesthesia in controlled hypertensive patients with preoperative ACE inhibitors.Material and methods: This descriptive case series study was conducted at a tertiary hospital in a developing country after approval from the Ethics Review Committee. A total of 115 adult patients, from 16 to 60 years of age, who have undergone elective surgery, have controlled hypertension on the desired drugs for at least six months, have no history of any cardiac event, and have taken the drug on the morning of the surgery, were included in the study after written consent. The demographic data of the patients were entered into the proforma. Preoperative systolic, diastolic, and mean arterial pressure were recorded by the researcher or an assignee in the preoperative holding area. The patients were followed in the recovery room by the team conducting the study until 10 minutes after the arrival of the patient in the recovery room. All statistical analyses were performed using Statistical Packages for the Social Sciences version 19 (SPSS Inc., Chicago, IL). p-value ≤0.05 was considered significant.Results: Of the 115 patients, 56 (48.7%) patients were in the age group between 51 and 60 years of age; 38 patients were between the ages of 41 and 50 years and only 21 patients were 40 years or less. On gender, 68 patients were female and 47 were male. According to body mass index (BMI), the majority of the patients were in the overweight group, amounting to 53 (46%), and 86 (74.78%) patients were known diabetics. Overall, 77 (66.96%) of the patients developed intraoperative hypotension with 41 (35.65%) patients requiring the use of vasopressors in order to correct the hypotension. No statistically significant difference was found between demographic and clinical variables.Conclusion: Intraoperative hypotension is more frequent in patients with controlled hypertension on ACE inhibitors although more studies need to be conducted on a larger population in order to determine a more definitive result
Analysis of K-Mean and X-Mean Clustering Algorithms Using Ontology-Based Dataset Filtering
In the field of computer science, data mining facilitates the
extraction of useful knowledge and patterns from a huge amount of data. Various techniques exist in the data mining domain to explore the links, associations, and patterns from data in data warehouses. Among these techniques, clustering is more prominent in analyzing raw and unlabeled data from a large volume of datasets. The clustering mechanism identifies similar features between data objects and arranges them into clusters. In this paper, we have compared the performance of K-Mean and XMean clustering algorithms using two datasets of student enrollment in higher education institutions. Our methodology incorporated ontology to filter the datasets and exploited Rapidminer environment to evaluate the performance of clustering algorithms. The results showed that X-Mean is more suitable for large datasets in terms of discovery and accuracy of clusters
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