Mathematical modeling and stability analysis of Pine Wilt Disease with optimal control

This paper presents and examine a mathematical system of equations which describes the dynamics of pine wilt disease (PWD). Firstly, we examine the model with constant controls. Here, we investigate the disease equilibria and calculate the basic reproduction number of the disease. Secondly, we incorporate time dependent controls into the model and then analyze the conditions that are necessary for the disease to be controlled optimally. Finally, the numerical results for the model are presented.

Academic performance of undergraduate dental students with learning disabilities

Aims To compare the academic performance of undergraduate dental students with known learning disabilities (LDs) to their peers.Methods This study analysed the results of students in applied dental knowledge (ADK) progress tests across four cohorts of dental students. A mixed model analysis of variance (ANOVA) was conducted to compare the performance of students with known disability to their peers. ADK test sitting was treated as a repeated measures variable, and the outcome variable of interest was percentage score on the ADK.Results Students' performance data on five ADK test sittings (ADK15, ADK16, ADK17, ADK18, and ADK19) by disability showed a significant main effect of test but no significant effect of disability or any interaction between disability and test.Conclusions This is the first study that explores the academic performance of dental students with a diagnosis of disability. The findings give reassurance to all stakeholders that, within the study population, students with LDs are not disadvantaged in knowledge-based assessments, demonstrating compliance with the legal obligations. Further research is required to explore how generalisable these findings are, as well as assess academic, clinical, and behavioural attributes of students with learning disabilities.

Tethered balloon-born and ground-based measurements of black carbon and particulate profiles within the lower troposphere during the foggy period in Delhi, India

The ground and vertical profiles of particulate matter (PM) were mapped as part of a pilot study using a Tethered balloon within the lower troposphere (1000m) during the foggy episodes in the winter season of 2015-16 in New Delhi, India. Measurements of black carbon (BC) aerosol and PM <2.5 and 10μm (PM_2.5 & PM₁₀ respectively) concentrations and their associated particulate optical properties along with meteorological parameters were made. The mean concentrations of PM_2.5, PM₁₀, BC_370nm, and BC_880nm were observed to be 146.8±42.1, 245.4±65.4, 30.3±12.2, and 24.1±10.3μgm^-3, respectively. The mean value of PM_2.5 was ~12 times higher than the annual US-EPA air quality standard. The fraction of BC in PM_2.5 that contributed to absorption in the shorter visible wavelengths (BC_370nm) was ~21%. Compared to clear days, the ground level mass concentrations of PM_2.5 and BC_370nm particles were substantially increased (59% and 24%, respectively) during the foggy episode. The aerosol light extinction coefficient (σ_ext) value was much higher (mean: 610Mm^-1) during the lower visibility (foggy) condition. Higher concentrations of PM_2.5 (89μgm^-3) and longer visible wavelength absorbing BC_880nm (25.7μgm^-3) particles were observed up to 200m. The BC_880nm and PM_2.5 aerosol concentrations near boundary layer (1km) were significantly higher (~1.9 and 12μgm^-3), respectively. The BC (i.e BC_tot) aerosol direct radiative forcing (DRF) values were estimated at the top of the atmosphere (TOA), surface (SFC), and atmosphere (ATM) and its resultant forcing were - 75.5Wm^-2 at SFC indicating the cooling effect at the surface. A positive value (20.9Wm^-2) of BC aerosol DRF at TOA indicated the warming effect at the top of the atmosphere over the study region. The net DRF value due to BC aerosol was positive (96.4Wm^-2) indicating a net warming effect in the atmosphere. The contribution of fossil and biomass fuels to the observed BC aerosol DRF values was ~78% and ~22%, respectively. The higher mean atmospheric heating rate (2.71Kday^-1) by BC aerosol in the winter season would probably strengthen the temperature inversion leading to poor dispersion and affecting the formation of clouds. Serious detrimental impacts on regional climate due to the high concentrations of BC and PM (especially PM_2.5) aerosol are likely based on this study and suggest the need for immediate, stringent measures to improve the regional air quality in the northern India.

Progress testing in undergraduate dental education: the Peninsula experience and future opportunities

BACKGROUND

Progress testing is well established as a longitudinal form of assessment in undergraduate medical programmes to measure growth in knowledge. Peninsula Dental School is the first school to use progress testing and remains the only one to do so.

AIMS

To share the experience of developing progress testing in an undergraduate dental programme as a major summative assessment tool at a newly established dental school in the United Kingdom.

METHODS

Data were collected for progress tests conducted from 2007 to 14. The tests were formative in the first 2 years of the programme and summative in subsequent years. Each test was based on 100 single best answer multiple-choice items with an appropriate vignette. The students chose their answer from 5 options. A score 1 mark is awarded for each correct answer, minus 0.25 for an incorrect answer and 0 for 'don't know' (DK). The standard setting for each sitting was carried out using Angoff and Hofstee methods.

RESULTS

There were two tests per year with each cohort undertaking eight tests in their 4 years of study providing a total 14 test occasions. The reliability of each test for each student cohort tests was measured using Cronbach's alpha. The average reliability over 42 test/cohort combinations was 0.753 (±SD 0.08). Data analyses show growth in knowledge of dental students across successive years with the largest increase in knowledge observed between tests 1 and 5 and concomitant reduction in DK responses.

CONCLUSION

This is the first study to report the establishment and use of progress testing as the principle form of written summative testing in an undergraduate dental curriculum. Progress testing is a valid and reliable tool to assess growth in knowledge longitudinally over the duration of a dental programme. Although a labour-intensive process, progress testing merits more widespread use in dental programmes.

Provider-reported acceptance and use of the Centers for Disease Control and Prevention messages and materials to support HPV vaccine recommendation for adolescent males

PURPOSE

We evaluated Florida-based physicians' awareness and use of the Centers for Disease Control and Prevention's (CDC) "You are the Key" campaign website, including messages to support physicians' human papillomavirus (HPV) vaccine recommendations.

METHODS

Using closed-ended and free-text survey items, physicians' (n=355) practices related to HPV vaccination recommendations for males and use of the CDC's materials were assessed. Descriptive statistics were calculated for closed-ended questions, and thematic analysis was conducted on free-text responses.

RESULTS

Over half of physicians were aware of the CDC's website (n=186; 57.9%); of those aware, fewer than half reported using the website (n=86; 46.2%). Slightly more than half reported awareness of the CDC's messages (n=178; 55.3%); however, less than one-third of those aware reported using them (n=56; 31.5%). Physicians' comments on the CDC's messages were favorable; 78.6-93.2% said they would use a message in clinic.

CONCLUSION

Additional research is needed to identify the best mechanisms for resource dissemination and to understand why physicians do not use these messages, despite favorable attitudes.

Transition of new dental graduates into practice: a qualitative study

AIMS

The aims of this study were to explore the transition of new dental graduates to gain a deeper understanding of the merits and challenges of a mentored year for new graduates in general dental practice settings.

METHODS

The study was conducted in the south-west region of England. Qualitative methods were used to engage a range of stakeholders in dental education including dental students, academics, general dental practitioners, new graduates, specialists and representatives of the postgraduate dental deanery. Purposive sampling was employed, and after ethical approval, participants were contacted through professional channels. All interview transcripts were transcribed verbatim. The data were imported into NVivo 10 (QSR International Pty Ltd) and analysed thematically.

RESULTS

Sixteen participants representing a variety of stakeholder groups were interviewed. The participants shared their perceptions and experiences regarding the transition new dental graduates into dental practice. The challenges and benefits are discussed along with strategies to facilitate a smooth transition.

CONCLUSIONS

This study provides an insight into experience of a mentored year for new dental graduates in general practice settings. Foundation training provides a structured introduction into general practice and serves as a safety net before new graduates gain further independence in clinical practice.

Estimating tuberculosis burden and case detection in Pakistan

BACKGROUND

The National Tuberculosis Control Programme (NTP) in Pakistan has officially achieved a tuberculosis (TB) case detection rate of 64% in 2011, with an estimated incidence rate of 230 per 100 000 population, but is likely to be missing an unknown number of patients, particularly in the private sector.

SETTING

All public and private sector providers in 12 randomly selected districts of Pakistan were included.

OBJECTIVE

To estimate TB incidence and TB notification rates in Pakistan in 2012.

DESIGN

A surveillance system was established among all eligible non-NTP providers in selected districts from January to March 2012. Record linkage and capture-recapture analysis was conducted.

RESULTS

Of 8346 TB cases identified after record linkage, 6061 were registered with the NTP. The estimated number of unobserved TB cases was 10 030 (95%CI 7800-12 910), which meant that the proportion of notified cases was 32% (95%CI 17-49). The calculated annual incidence was 878 000 cases (95%CI 573 000-1 675 000), corresponding to a rate of 497/100 000 (95%CI 324-948) annually in the population.

CONCLUSION

The study estimated that the proportion of cases notified to the NTP was low, with actual incidence rates being higher than official estimates. TB surveillance should be strengthened to reduce under-reporting.

Management of impacted wisdom teeth: teaching of undergraduate students in UK dental schools

INTRODUCTION

Wisdom tooth removal is one of the most common oral surgical procedures performed across the world. The aim of this study was to gauge the teaching and training of impacted wisdom teeth in undergraduate dental programmes across the UK. The objectives were to identify consistencies and variations in theoretical instructions and clinical training as well as approaches to management of impacted wisdom teeth.

METHODS

This was a cross-sectional survey utilising an online questionnaire. A purposefully designed pro forma with open- as well as closed-ended questions was used. The questionnaire was hosted online on the school's blackboard academic suite (Emily). Prior to conducting the study, approval was gained from the Research and Ethics Committee, and all the ethical principles pertaining to data protection were strictly followed. E-mail invitations were sent to oral surgery leads in all dental schools in the UK. The participants were provided with an information sheet, and an informed consent was obtained. The participants were invited by e-mail to complete the questionnaire online voluntarily.

RESULTS

A total of 16 dental schools offering an undergraduate course in dentistry in the UK, 13 responded positively. (response rate = 81.25%). In majority of dental schools, this subject is taught in the 4th and 5th years. A pre-clinical competency on phantom heads is a requirement in six schools, whilst only one school requires the students to pass a clinical competency. The clinical exposure of students to wisdom tooth surgery is quite variable. Although the dental schools are fairly consistent in their teaching with regard to the indications for surgical intervention, diagnostic/treatment modalities as well as the post-operative care, interesting variations were also observed.

CONCLUSIONS

This study, perhaps the first of its kind, provides useful insights into management of impacted wisdom teeth, as taught in the undergraduate dental programmes across the UK.

Use of peer assessment in tooth extraction competency

INTRODUCTION

Peer assessment is a widely recognised practice in higher education and is being increasingly utilised in healthcare education. It offers multiple advantages and may play a useful role in enhancing students' learning experience. This study was carried out to evaluate the utility of peer assessment in tooth extraction competency in simulated dental learning environment (SDLE).

METHODS

Year 2 dental students were invited to participate in a formative, peer assessment exercise on forceps tooth extraction in SDLE. The ratings made by peers in the formative assessment were compared with the ratings made by academic supervisors in an equivalent summative assessment.

RESULTS

One hundred and twenty-two students participated in both the formative and summative assessments. Descriptive statistics demonstrated that the majority of students were given the same rating in both assessments. However, there were a number of students who were rated as 'Competent' in one assessment and 'Not Competent' in the other assessment. Spearman's Rho correlations showed that there were weak relationships between the formative and summative assessments. There was also weak inter-rater reliability for the ratings of the peers and academic supervisors, as measured by the intraclass correlation coefficient. Feedback from the students and academic supervisors showed unanimously positive perceptions about the peer assessment experience, and they expressed the desire for incorporating peer assessment in other competencies.

CONCLUSIONS

This study shows mixed results with regard to the value of the peer assessment. Given the potential utility of peer assessment as a tool to augment and enrich students' learning experience, further work needs to be done to evaluate the use of peer assessment in operative competencies in dentistry.

Lipid profile and glycosylated hemoglobin status of gestational diabetic patients and healthy pregnant women

AIM

Lipid profile and glycosylated hemoglobin level changes in gestational diabetes. The extent to which this alteration takes place is still not clearly documented.

MATERIALS AND METHODS

To add a clear answer to this question, lipid profile parameters, and glycosylated hemoglobin status were determined in patients with gestational diabetes mellitus and compared to healthy pregnant women (controls).

RESULTS

Fasting plasma glucose levels, plasma glucose levels 1 hour, and plasma glucose levels 2 hours after 75 gm oral glucose administration (oral glucose tolerance test) were significantly higher in patients with gestational diabetes as compared to controls. Glycosylated hemoglobin was significantly higher in gestational diabetes than in controls. It was observed that there was a significant increase in serum cholesterol and serum triglyceride level in cases with gestational diabetes when compared to healthy pregnant women.

CONCLUSION

The results of our study suggest that abnormal glucose levels, glycosylated hemoglobin, serum cholesterol, and serum triglycerides play an important role in pathophysiology of gestational diabetes, and therefore, extensive studies are required. Early diagnosis of gestational diabetes will decrease adverse neonatal and maternal outcomes.