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Objective. The aim of this in vitro study was to evaluate the effect of an oxide nanocoating to prevent colour degradation of maxillofacial silicone elastomers following accelerated ageing. Material and Methods. Specimens (N = 40) of specified dimensions were fabricated in Factor II room temperature vulcanizing (RTV) silicone and processed according to the manufacturer’s instructions. Two groups were classified with 20 specimens each. Specimens in the first group were coated with titanium dioxide (TiO2) by atomic layer deposition technology. Colour stability test was conducted with a UV-VIS spectrometer (Schimadzu) for both titanium dioxide nanocoated and uncoated specimen groups after subjecting them to accelerated ageing. It was analysed using the CIE L*a*b method. Results. The average colour change was highest for uncoated specimens (2.868), and the average colour change for titanium dioxide-coated specimens was significantly low (1.774). The average colour change of uncoated specimens (2.868) was close to the acceptable threshold value (3), and that of coated specimens (1.774) was far below the acceptable threshold (3). Conclusions. The colour change that occurred in titanium dioxide nanocoated specimens following accelerated ageing was significantly lower than that in the uncoated group, showing that the TiO2 nanocoating was effective in reducing the colour degradation of silicone elastomers. Clinical Relevance. Maxillofacial prostheses fabricated from silicone elastomers go through undesirable colour degradation over time. The development of a scientific technique that retards the colour deterioration of silicone prostheses would be of great clinical significance.

Inertial impactors are an important part of aerosol science where they are used to obtain particle size distributions in a wide range of practical and scientific applications. A shortcoming of these devices is that the number of bins in the resulting distribution is limited to the number of impactors in an impactor cascade. Recent work has shown that if the ratio of the nozzle-to-impactor distance (S) to the nozzle diameter (W) is very small, S/W ∼ O(0.01), the normally disk shaped particle impaction pattern becomes a ring. Under these conditions the ring diameter is proportional to the particle diameter, presenting an opportunity for developing impactors capable of sub-stage particle diameter sizing. Before such impactors may be developed, however, further information is required regarding how the diameter of the aforementioned rings vary with S/W and particle diameter. Herein, experiments are presented where ring-shaped deposition patterns are obtained for a range of particle diameters and S/W. These results are consolidated to provide a relationship between the relevant dimensionless variables: the Stokes number (dimensionless particle diameter), S/W, and dimensionless ring diameter. Computer simulations of particle trajectories under the experimental conditions are presented and are used to reveal the underlying mechanism of this effect. Finally, a discussion is presented of practical approaches for using these results to obtain high resolution particle size distributions from impactor cascades. Copyright © 2021 American Association for Aerosol Research

Urbanization has both benefits and costs. This chapter summarizes research findings on how urbanization enhances productivity and economic growth in both rural and urban sectors, taking the case of India. It studies the relationship between urbanization and growth. Based on extensive data analyses of urbanization, it finds no impact of urban–rural inequalities on urbanization, but significant impact on the population of the largest city in the state. When accounting for the two-way relationship between urbanization and the rural–urban income ratio, it finds that urbanization increases urban–rural inequalities initially, but at higher levels reduces them. Urbanization benefits rural development since the chapter finds that it has a positive impact on increasing the rural–urban income ratio, and the evidence regarding remittances. Policy implications regarding telecommuting and investments in urban infrastructure are summarized. Lessons from India and the People’s Republic of China for each other’s urbanization are discussed.

This paper presents research that examines the perceptions of school principals of the “Teach Less, Learn More” (TLLM) initiative in Singapore schools. A qualitative research was conducted with 13 school principals to explore their understanding of TLLM and their perception of the challenges that they faced in the implementation of TLLM. The findings show that the research participants agreed that TLLM was a good policy that would prepare students with knowledge and skills for the future. However, there were also many challenges, the most pertinent of which being the readiness of the students and teachers for a new teaching and learning paradigm.

The rise of interest in the learning organization (LO) concept attests to the value of learning by individuals and organizations for continuous improvement and adaptability to the ever-changing environment. Although the LO concept originated from business contexts, it was subsequently extended to educational organizations, particularly to schools. This paper presents research on the way LO is practised by a school in Singapore that subscribes to the LO philosophy. Using Ortenblad’s four integrated LO aspects (organizational learning, learning at work, learning climate and learning structure) as a framework of analysis, the research shows that the school practises the four aspects in a way that is unique to its school context, but that wider cultural factors have to be taken into account when interpreting LO in an Asian school context.

There is growing demand for management consulting as organizations look to external expertise to enhance their competitiveness. Not only do management consultants have wide experience that transcends that of individual client companies, but as outsiders they also bring perspectives that challenge routinized management practice. This research focuses on that challenge by looking at how they perceive their attempts to change entrenched mental models. A qualitative study using in-depth interviews with 18 management consultants was conducted in Singapore. The findings identify ways by which management consultants establish authority and seek to transform mental models. Two overarching approaches include building relationships with clients and explicit use of management concepts. The research also highlights some of the challenges perceived by management consultants in the process of changing clients' mental models.

Resorption of the root can be either internal or external and may manifest in the form of perforations on the middle third of the root surface. These resorptions may have undesirable sequelae such a gingival inflammation, periodontal destruction and bone resorption. Numerous materials have been tested to treat such lesions in the past. The present case makes use of mineral trioxide aggregate (MTA) and a periodontal flap for the management of external root resorption. With the success of treatment and desirable outcomes at follow-up appointments, MTA proved to be an effective and viable material of choice.

One of the key factors that contribute to effective management of schools is the professional development of principals. The role of the principal has become more complex with the dynamic and constant reforms in the educational environment. The present study focuses on the professional development of principals in New Zealand and Singapore. The identified categories for comparison include similarities in knowledge on leadership, models and skills that are important for aspiring principals. Differences include the selection process, programme design, modes of learning, futuristic projects and visits to other institutions. The study contributes to our understanding of key dynamics in the professional development of aspiring principals by identifying categories for comparison and discussing their relevance for analysing similarities and differences between these. The study also points to relevant interactions between professional development and the local environment.

The study of heavy metal distribution in coastal water and surface sediments is an important component in understanding the distribution levels as well as assessing the cause of anthropogenic influences on the marine ecosystem. During the last Twenty Five years, the coastal environment of southeast India had experienced intense developments in industry, urbanization and aquaculture. Several metals are known to be discharged frequently through industrial and domestic effluents along the southeast coast of India. The present study was carried out to determine the Heavy Metal Distribution in the coastal Waters and sediments of Mandapam, Thoothukudi, Arumuganeri and Kanyakumari Coasts. The sampling of coastal water and sediments was carried out from October 2013 to September 2014. The enrichment in the concentration of heavy metals in the samples that are close to the coastal areas indicated that higher concentration was due to the anthropogenic activities in the coastal area. Hence, this present study used to investigate the Heavy metal levels of contamination in this area, and also useful for further impact evaluation.

Schools are continuously looking for new ways of enhancing student learning to equip students with skills that would enable them to cope with twenty-first century demands. One promising approach focuses on design thinking. This study examines teacher's perceptions, experiences and challenges faced in adopting design thinking. There is a lack of empirical research on the adoption and implementation of the design thinking process in educational context from the teachers’ point of view. This paper fills this gap and also provides insight on a recent initiative adopted in Singapore schools. Qualitative case study research was carried out in a school using teacher narratives. Data includes in-depth face-to-face interviews and participant observation. The findings show that teachers perceive that design thinking holds the potential for enhancing skills such as creativity, problem solving, communication and team work as well as empower students to develop empathy for others within and beyond the community. The r...

Aims: It has been estimated that >30% of male infertility cases are of idiopathic etiology. Recent studies revealed a positive connection between periodontal pockets and sperm submotility, which proposes that periodontitis may have a role in male infertility and inadequate semen quality. The aim of the present investigation was to inspect the relationship between male fertility parameters and the periodontal status of male patients attending in vitro treatment (IVF) clinic. Materials and Methods: The study participants comprised 85 men going to the facility for sperm investigation before semen insemination. The nature of sperm was surveyed by the WHO 2010 criteria. On the same day, male patients were examined for periodontal parameters. Results: The patients were determined to have either gingivitis (24.7%) or periodontitis (75.3%). Normospermia was credited to 23.5% and oligozoospermia to 43.5%. Sperm submotility was seen in 76.4% of patients. A higher number of sites with clinical attachment loss showed a positive correlation with sperm submotility and sperm count. Conclusions: The findings of the present study showed a conceivable relationship between male infertility, decreased semen quality, and periodontal diseases in men visiting IVF centers. Periodontitis may subsequently play a role in male infertility.

A body of literature asserts that group work can be beneficial in enhancing learning and in developing specific skills among students. This research builds on the literature and on Gardner’s (2006a) five notions of mindsets: disciplined, synthesising, creation, ethical and respectful, as a descriptive framework to explore and understand the benefits and skills learnt or developed through group work. Gardner describes mindset as a way of thinking and acting. A qualitative research project was undertaken in a New Zealand university using in-depth interviews with post-experience students. The findings suggest that, though the post-experience students do possess skills that enabled them to integrate diverse perspectives, make new connections with shared knowledge and evaluate critically, they often lack specific mindsets that are critical in organisations that rely on group work to enhance their productivity.

PurposeThe purpose of this paper is to explore practitioner and post‐colonial perspectives on the implementation of learning organisation theory and practice in a non‐Western setting.Design/methodology/approachA qualitative interpretive study, using in‐depth interviews and participant observation, was conducted in two public organisations in Singapore. The study looked at relationships between the concepts of the learning organisation and of Singapore national culture, as the members of the organisations saw them. This study is presented and then discussed in commentaries from two different perspectives, i.e. the “insider” perspective of a Singaporean practitioner, and the “outsider” perspective of a New Zealand academic using a post‐colonial critique.FindingsThe findings indicate that Western LO practitioners need to pay specific attention to the cultural values expressed by non‐Western organisational members, and to their own cultural limitations and biases which may be embedded in the implementation of LO programmes. This process requires an active dialogue between both parties.Practical implicationsThe findings indicate that practitioners need to pay specific attention to the cultural values of employees, and to the cultural assumptions of new management programmes, when adopting Western concepts of management to non‐Western organisations.Originality/valueThis is an empirical study that reveals the particular tensions experienced in two specific non‐Western organisations when LO practice was introduced without explicit exploration of its Western cultural underpinnings. The paper argues that the development of an LO discourse of organisational post‐colonialism can provide a valuable critical framework to examine the global mobilisation of LO concepts.

Feedback to students is an important feature of assessment in higher education. Constructive and timely feedback guides students to improve on a continuous basis in the process of their tertiary education. This paper outlines an exploratory study based on survey research, which was conducted on a large sample of undergraduate students on management courses in a New Zealand university. Following a review of the relevant literature a conceptual model was developed using systems thinking principles. A questionnaire was designed consisting of 20 closed Likert questions and two open questions designed to explore students’ perceptions of the feedback given to them on their formative assessments. Quantitative and qualitative analyses were undertaken of the data collected from over 600 valid responses. The quantitative analysis consisted of descriptive statistics, an exploratory factor analysis and Pearson's correlation analysis. The four main factors to emerge were: improvement of work quality, improvement of results, need for feedback and quality of feedback. The qualitative analysis was based on these themes. The results of these analyses are discussed in this paper. This paper attempts to contribute to the ongoing discussion regarding the better understanding of the complex relationships between feedback and student learning in tertiary level management education.

Over the years, there has been an increased interest among educators and researchers that today's students need new skills to excel in the highly globalised world. This resulted in looking for new pedagogies to prepare students for academic and professional life. This research builds on Gardner's (2006) framework of disciplined, synthesising, creating, respectful and ethical mindsets, which would develop capacities and skills required for the future. Qualitative research, using in-depth interviews was conducted in a New Zealand university to understand how students from two disciplines react to the five mindsets. The findings suggest that though there were some similarities and differences in perceptions by the students, the ethical mindset was strongly demonstrated by all respondents. Implications for educators and future research are discussed in this chapter.

School leadership literature suggests that school effectiveness and ongoing improvement rely on school leaders and principals. Despite significant contributions made by principals towards teaching and learning in schools, there have been few studies that explore principals’ perceptions of the factors underpinning their successes and achievements. Drawing on one of Senge's disciplines, personal mastery, this research examines principals’ perceptions of some processes that enable their successes. A qualitative research project was undertaken in Singapore using in-depth interviews. Analysis was informed by movement between theoretical dimensions and emerging themes from participants’ discussions of their leadership experiences. The findings suggest that personal mastery has a positive influence upon principals and their ability to demonstrate effective school management.

PurposeThe purpose of this paper is to explore the dynamics and key success factors in the development of communities of practice (CoP).Design/methodology/approachA qualitative case study, using in‐depth interviews, was conducted in a multinational company (MNC) in Singapore.FindingsThe findings indicate that CoPs can facilitate the creation, sharing and utilisation of knowledge in an organisation, positively affecting its strategy, operations and bottom line. The key factors that nurture CoPs to promote innovative learning and knowledge‐sharing environments are leadership, culture and individual motivation.Practical implicationsThe findings indicate the value of informal CoPs in promoting innovative cultures with high levels of collaboration among organisational members.Originality/valueThis is an empirical study that reveals the dynamics of CoP development in an MNC and the key success factors of CoP development from the point of view of the employees in the company.

Background: The prevalence and complications of nonalcoholic fatty liver disease (NAFLD) have increased dramatically over the past decade. The pandemic of lifestyle disorders and their role in the development of NAFLD encourage studies in this aspect. Aims and Objectives: To evaluate the association of laboratory parameters such as plasma glucose (fasting, postprandial, and glycated hemoglobin), serum lipid profile, and liver enzymes with NAFLD. Materials and Methods: Our case–control study enrolled 150 participants [81 cases (sonological evidence of fatty infiltration of liver) and 79 controls] in a period of 2 years. All laboratory investigations were done in the central laboratory of the institution using appropriately standardized techniques. Institutional ethics committee approved this study and written informed consent was obtained from all study participants. Data were analyzed using free software R®, nominal variables were compared using independent sample t-test and Mann–Whitney U-test; categorical variables were compared using Chi-square test. P < 0.05 was considered statistically significant. Results: Higher number of male participants (56.3%) enrolled in the study. Significant difference in total cholesterol (TC) (P < 0.001), low-density lipoprotein (LDL) (P < 0.001), triglycerides (TG) (P < 0.001), alanine aminotransferase (ALT) (P = 0.002), TC/high-density lipoprotein (HDL) (P = 0.001), and TG/ HDL (P < 0.001) was observed between cases and controls. Significant association with NAFLD was observed for TG (P = 0.001), TC (P < 0.001), dyslipidemia (P = 0.02), aaspartate aminotransferase (AST) (P = 0.03), and ALT (P < 0.001). Conclusion: High prevalence of prediabetes and diabetes were observed among participants undergoing voluntary health checkup. Significant difference in TC, LDL, TG, TC/HDL, TG/HDL, and ALT was observed between cases and controls. Significant association with NAFLD was observed for TG, TC, dyslipidemia, AST and ALT.

Students are considered to be the main ‘customers’ in universities and polytechnics and increasingly they seek to have their needs met. This is one of the main reasons for persistent calls for the improvement of teaching in higher education. Tutors play an important role in the delivery of undergraduate education, although they are often perceived as a ‘neglected’ or ‘invisible’ group. This paper assesses students' perceptions of tutors and the factors that contribute to their learning in a New Zealand university. Survey questionnaires were administered to management students at the end of their course, to gather information on their perceptions of tutor effectiveness and to reflect on their overall tutorial experiences. Quantitative and qualitative analyses were undertaken of the data collected. The results supported the initial hypotheses that the learning environment, positive and constructive feedback and stimulating tutorials improve student learning and lead to higher levels of student satisfaction ...

In Singapore, decentralization and school-based reforms are key words within the current education reform agenda. This article argues that a key success factor in this agenda is transformational leadership in school. With more autonomy given to the school, transformational leadership at the school level will facilitate the development of school culture and staff capacity, which will in turn facilitate bottom-up initiatives. This article reviews the literature on transformational leadership, reports some research on transformational leadership in schools in other countries, and draws on the results of previous research on transformational leadership in a Singapore school to support its argument.

PurposeTo report on a case study that examines how the Learning Organisation (LO) concept can be applied in a Singapore school and the challenges that the school faces in the process.Design/methodology/approachA qualitative research inquiry was adopted using ethnographic methods. Data includes in‐depth face‐to‐face interviews, observation of meetings, informal conversations with students and parents. The study adopted an interpretive paradigm based on post‐positivist theories.FindingsWhile the LO concept can be applied in the school context to its benefit, there can be potential cultural conflicts, ambiguities and paradoxes, as highlighted in the paper. The wider societal culture has a profound influence on how the structures, authority and relationship between subordinates and superiors in a school.Research limitations/implicationsEmpirical data is limited to only one school in Singapore. A longitudinal study involving more schools in Singapore will generate a better sense of the benefits and challenges of LO in schools.Practical implicationsSingapore schools need to address the cultural norms of hierarchy and conformity in order to fully embrace the LO concept.Originality/valueThere is a lack of empirical research on how the LO model can be applied in an Asian school context. This paper represents a first attempt to fill this gap and also offers some practical recommendations to schools that are aspiring to be learning schools.

This paper argues that the Learning Organisation (LO) concept is not culturally neutral and that any assessment of its usefulness must be situated within an understanding of the national cultural framework in which organisations are embedded. Although the Learning Organisation (LO) concept is popular amongst both practitioners and academics in a wide range of countries, the theory is largely grounded in the thought of US business schools and the experience of large US corporations. National culture is invisible in the LO literature. This is primarily written from an American standpoint and the degree to which it is relevant to international practice is debatable. This paper surveys the LO concept within the context of globalisation, focusing on Singapore organisations. It draws on a critical examination of Hofstede's national culture dimensions to create a framework for the study of the adoption and adaptation of the LO concept by Singapore organisations.

This paper focuses on air and water pollution in India’s cities, provides empirical evidence to demonstrate the seriousness of the challenges, discusses the relevant policies of national and local government that are used to address the challenges, discusses relevant political economy issues related to introducing pollution taxes or other policies which are aimed at “green” cities.

Background: Recombinant human bone morphogenetic protein-2 (rhBMP-2) technologies have been shown to significantly support alveolar bone. The purpose of this study was to explore the effect of rhBMP-2 following periodontal flap surgery in vertical defects on clinical and radiological parameters. Methods: A randomized double-blind controlled trial was carried out, wherein rhBMP-2 was used in the test group after open flap debridement (OFD). The control group was only OFD. The same examiner carried out both clinical and radiographic measurements at baseline, 6 and 9 months. Results: In rhBMP-2 + OFD sites, the probing pocket depth reduction was 1.45 ± 0.76, 2.50 ± 0.69 at 6 months and 9 months, respectively (both P < 0.001) and clinical attachment gain was 0.92 ± 0.76, 1.31 ± 0.48 at 6 months, and 9 months, respectively (both P < 0.001). Radiographic fill was 1.14 ± 0.73, 1.85 ± 0.83 at 6 months, and 9 months postoperatively (P < 0.001) and percentage of original defect resolved at 6 and 9 months was 40.2 ± 18.6, 60.1 ± 15.8, respectively. Conclusions: The periodontal therapy can include rhBMP-2 to enhance periodontal regeneration. The clinical and radiographic improvement are demonstrated in this study.

Introduction: To compare the effects of hyaluronan (Gengigel) alone and in combination with scaling using clinical, microbial, and lactate dehydrogenase (LDH) parameters. Materials and Methods: In this, the three treatment groups included were scaling, scaling plus local application of Gengigel, and Gengigel alone. The 0.2% hyaluronic acid (HA) gel was applied topically and intrasulcularly 0.8% hyaluronan was applied. The clinical parameters, and microbial and biochemical analyses of gingival crevicular fluid (GCF) LDH were assessed. Intragroup comparisons were made by Student′s unpaired t-test and intergroup comparisons were done using one-way analysis of variance followed by post hoc Turkey′s test. Results: At the end of study period (0-56 day), intergroup comparison demonstrated no significant reduction in plaque index (PI) (0.07 NS), gingival index (GI) (0.99 NS), and LDH (0.70 NS) values. A significant correlation was found between LDH values and bleeding index at all study intervals (0 days, 28 days, and 56 days); gingival index (GI) (0.007 S) was significantly correlated on day 0 and day 56. The microbial reduction was demonstrated. Conclusion: These changes in the clinical, microbial, and biochemical parameters reported with the different treatment modalities clearly support that the use of Gengigel would act as an advantageous adjunct to scaling. Further studies are required to confirm the Gengigel effect using histologic methods.

Background: Halitosis has been correlated with the concentration of volatile sulfur compounds (VSCs) produced in the oral cavity by metabolic activity of bacteria colonizing the periodontal pockets and the dorsum of the tongue. It has been assumed that there is a relationship between periodontal disease and diabetes mellitus. Objectives: The aim of the study was to assess the malodor using the organoleptic method and tanita device; to quantify odoriferous microorganisms of subgingival plaque and tongue coating, such as P. gingivalis (Pg), T. forsythia (Tf), and F. nucleatum (Fn) using polymerase chain reaction (PCR) in nondiabetic and diabetic chronic periodontitis patients. Patients and Methods: Thirty chronic periodontitis patients (with and without diabetes) with 5-7 mm pocket depth, radiographic evidence of bone loss, and presence of oral malodor participated in this study. Subjective assessment of mouth air was done organoleptically and by using a portable sulfide monitor. Tongue coating was also assessed. Results: The scores of plaque index, gingival index, gingival bleeding index, VSC levels, and tongue coating between the nondiabetic and diabetic patients were not significant (P>0.5). In nondiabetic patients, Fn was found to be significantly (P0.5). In diabetic patients, Fn and Tf have shown significant (P

We sought to assess the role of angiotensin-converting enzyme (ACE) inhibitors on systolic blood pressure (BP), endogenous antioxidant enzymes and histopathological changes in pressure-overload rats.Pressure overload was produced in male rats by abdominal aortic banding (AAB) using a blunt 22-gauge needle, as a model of cardiac hypertrophy. After surgery, AAB-induced hypertensive (AABIH) groups were treated with captopril 4 mg and ramipril 10 mg/kg per day p.o. for 16 weeks. At 16 weeks, rats were observed for general characteristics and mortality, non-invasive blood pressure (NIBP) and endogenous antioxidant enzyme catalase and superoxide dismutase (SOD) activity and histological evaluation of target organs.In the AABIH group a significant increase in systolic BP was observed in week 3 (149.3 ± 0.821) and persisted until week 16, along with lower levels of serum catalase (144.7 ± 2.204) and SOD (12.92 ± 0.4601) activity compared to the control group. Captopril and ramipril treated groups showed a significantly smaller increase in systolic BP (25.47 ± 3.685, 20.21 ± 3.306) and greater serum SOD (27.33 ± 2.338, 28.95 ± 1.143) and catalase (181.7 ± 8.407, 187.9 ± 8.497) activity, respectively, than the hypertensive rats. The histological changes induced in target organs (heart, liver, kidneys and thoracic aorta) in AABIH rats were attenuated in treated rats.ACE-inhibition causes an improvement in myocardial antioxidant reserve, reduces oxidative stress, and prevents pathophysiological alterations, while showing a trend for potential target organ protection in hypertensive rats.

Senge's learning organisation (LO) concept was introduced in many Singaporean schools to promote a learning culture. The implementation of the LO concept in organisations was in response to Singapore's call for all schools to be 'thinking schools' and the Singapore Ministry of Education's pronouncement that the foremost prerequisite of a thinking school is that it must be a learning organisation. This paper describes a qualitative study that was conducted in a secondary school that practiced the LO concept. The research was undertaken with a key focus on understanding how the implementation of the LO concept has enhanced open communication, a learning culture and critical and creative thinking. The research also identifies constraints, especially cultural ones. The findings suggest that LO concept produced significant progress towards an environment of a shared learning culture, effective communication and good working relationships among the staff. It has also helped to increase the level of awareness and the importance of critical and creative thinking in the school. However, strategies and activities used to promote critical and creative thinking were used sparingly so as not to undermine the 'academic excellence' that is important to the school's reputation as a 'good school.' Also, the curriculum structure and compulsory coverage of syllabus for examination as well as general cultural inhibitions were some of the factors that limited the growth of critical and creative thinking in the school. The paper concludes with implications for both academics and practitioners within organisations.