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Science literacy shows that students should be familiar with the most basic principles of science, one of which is Newton's Law. The purpose of this research is to determine the ability of high school students in Newton's Law of science literacy using a test based on Nature Of Science (NOS). The NOS-based instrument consists of 25 multiple-choice test items with 4 alternative options modified by Nature of Science Literacy Test (NOSLiT) and is specifically developed on Newton's Law. The subjects of this study are 110 high school students of the IPA program. Data collection techniques were performed using tests based on NOS-based instruments and interviews using questionnaires. The method of his research used descriptive qualitative. The results show that the average percentage of students who answered correctly was 38.73% of 110 students. The highest average percentage was shown in the scientific disposition framework is 53.33% of students answered correctly, and the lowest in the major misconception about science framework is 23.93%. Based on the results of the study can be concluded that students who can't answer correctly about the NOS are the students who are less able to understand the language of the questions presented in the instrument NOS. Other factors that influence student performance in answering questions on the NOS are knowledge of science that is still less widespread, low student understanding and still many misconceptions on Newton's law. It can be said that the student has a low literacy ability in science.

Nature of Science Literacy Test (NOSLiT) is an instrument to measure students' understanding on scientific facts so they fulfilled the success of science literacy in high school students. The purpose of this research was to find out students' science literacy based on NOSLiT instruments. The method used for this research is descriptive qualitative and descriptive quantitative. This research samples were 29 students of 10st grade drawn from one public school in Karanganyar Regency, Central Java, Indonesia. The result showed that majority of the students have reached the science literacy while few of them have not fulfilled the requirements yet. Students have fulfilled frameworks such as science nomenclature, experimental ability and basic observation, scientific postulate, and rules of scientific evidence in such a large number. While frameworks such as scientific disposition and major misconception about science were still in small number. Science literacy values familiarity as well. Students taken as samples for this research were not really familiar with the type of questions asked during the science literacy test. Thus, their result was still below the average students in United States. The average of science literacy for student in X Science 4 with NOSLiT instrument is 57.14%.

BACKGROUND Although tobacco is the primary etiologic factor for oral precancerous lesions in India, evidence from other sources indicates that diet may modify risk. This case–control study was designed to minimize a variety of biases in its attempt to investigate the relation between diet and oral precancerous lesions. METHODS In a house-to-house survey of 5056 tobacco users in a rural area of Ernakulam district in Kerala, India, 226 individuals (44 females and 182 males) were found to have precancerous lesions (cases), which in 4 cases proved to be cancer. From among the examinees, an equal number of controls who were free of oral mucosal lesions and were matched to the cases regarding age (±5 years), gender, ward of residence, and use of tobacco also were enrolled. Dietary data were obtained using a customized interviewer-administered food-frequency questionnaire. All subjects and interviewers were blinded to the disease status of the subject. RESULTS After controlling for tobacco use, intake of fruits, vegetables, and β-carotene evinced inverse trends in risk (P < 0.05), with an average reduction of over 10% per quartile of exposure. Associations with certain micronutrients appeared to differ according to gender, with an apparent 20% reduction in risk per mg of zinc consumed per day among men and the suggestion of an increased risk among those women in the lowest quartile of iron intake (an increase of approximately 2.5-fold) and ascorbic acid intake (an increase of approximately 70% increase) compared with other women (P < 0.10). CONCLUSIONS Consumption of vegetables, fruits, and several micronutrients may inhibit precancerous lesions of the oral cavity. Cancer 1999;85:1885–93. © 1999 American Cancer Society.

Globally, oral cancer is one of the ten common cancers. In some parts of the world, including the Indian subcontinent, oral cancer is a major cancer problem. Tobacco use is the most important risk factor for oral cancer. The most common form of tobacco use, cigarette smoking, demonstrates a very high relative risk--in a recent cohort study (CPS II), even higher than lung cancer. In areas where tobacco is used in a smokeless form, oral cancer incidence is generally high. In the West, especially in the U.S. and Scandinavia, smokeless tobacco use consists of oral use of snuff. In Central, South, and Southeast Asia smokeless tobacco use encompasses nass, naswar, khaini, mawa, mishri, gudakhu, and betel quid. In India tobacco is smoked in many ways; the most common is bidi, others being chutta, including reverse smoking, hooka, and clay pipe. A voluminous body of research data implicating most of these forms of tobacco use emanates from the Indian subcontinent. These studies encompass case and case-series reports, and case-control, cohort, and intervention studies. Collectively, the evidence fulfills the epidemiological criteria of causality: strength, consistency, temporality, and coherence. The biological plausibility is provided by the identification of several carcinogens in tobacco, the most abundant and strongest being tobacco-specific N-nitrosamines such as N-nitrosonornicotine (NNN) and 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK). These are formed by N-nitrosation of nicotine, the major alkaloid responsible for addiction to tobacco. The etiological relationship between tobacco use and oral cancer has provided us with a comprehensive model for understanding carcinogenesis.

Oral cancer is caused by chewing and smoking of tobacco. To assess the feasibility of primary prevention of oral cancer, two cohorts were studied in base-line surveys and then followed up annually for 10-yr in Ernakulam district of Kerala state. The intervention cohort consisted of 12212 tobacco users aged 15 yr and over, who were exposed to a concentrated program of education against tobacco use. The control cohort was a non-concurrent cohort of 6075 tobacco users studied using similar methods but with a minimal amount of advice against tobacco use. The stoppage of tobacco use increased and the incidence rate of leukoplakia decreased significantly and substantially in the intervention cohort compared to the control cohort. The decrease in the incidence of leukoplakia was indicative of the decrease in the risk of oral cancer since the two were intimately related. This study demonstrated feasibility of primary prevention of oral cancer.

This study ascertained demographic information and prevalence rates of medical problems among 571 new and consecutive dental patients attending the emergency clinic of the School of Dentistry, The University of the West Indies. Patients were interviewed by specially trained and calibrated dental students and interns. Various medical problems of patients were recorded in individual open-ended case sheets, maintaining their privacy and confidentiality. This information was then transcribed into a specially designed and pretested form. The data were entered into a Microsoft Excel spreadsheet and analyzed using the SPSS statistical package to obtain the prevalence rates of medical conditions, which were then cross-tabulated with gender, age, ethnicity, and other variables. Significance of differences, if any, was evaluated by chi-square test. In all, 303 medical conditions were encountered in 239 individuals, giving a prevalence rate of 42 percent. Hypertension (12.6 percent), diabetes (6.1 percent), asthma (5.8 percent), arthritis (4.7 percent), and various allergies (8.3 percent) constituted an important segment of the problems. Gender, ethnic, and age differences were also evident for some diseases. In this study-which was the first of this kind in the West Indies-vital information on medical problems among dental patients was obtained by interviews conducted by dental students and interns, forming an important part of their dental education.

A case-control study to elucidate the etiology of oral submucous fibrosis was conducted in Bhavnagar, Gujarat. Sixty consecutively arriving oral submucous fibrosis patients at a dental clinic were selected as cases. An equal number of controls matched for age, sex, religion and socioeconomic status were selected from individuals who did not exhibit any oral mucosal lesion or condition. Among cases, 98% chewed areca nut regularly in one form or the other whereas among controls 35% chewed areca nut, giving an overall relative risk of 109.6. Areca nut chewing was practiced most commonly in the form of mawa: a mixture containing mainly areca nut (over 90% by weight), some tobacco, and a few drops of lime. Mawa chewers and those who chewed mawa along with other chewing habits showed very high relative risks. The relative risks increased with increase in the frequency as well as the duration of chewing habits. In a bivariate analysis the effect of frequency and duration of chewing appeared to be multiplicative. The present findings confirm areca nut as the most important etiologic factor in oral submucous fibrosis.

Sickle cell anemia is a frequent hemoglobinopathy in the Caribbean. While vaso-occlusion induced tissue injury in sickle cell anemia is common in various organs, orofacial lesions are rare. A 14-year-old Afro-Trinidadian boy suffering from sickle cell anemia developed an acute facial swelling, mimicking facial cellulitis of dental origin, which was caused by sickle cell-related hemorrhage. He also exhibited gingival enlargement, considered to be an outcome of repeated hemorrhagic episodes and fibrous repair. A new finding is the presence of erythrocyte-filled intraepithelial blood vessels in the gingival epithelium. We hypothesize this phenomena is a tissue response to hypoxia that occurs in sickle cell disease.

Although tobacco is the primary etiologic factor for oral precancerous lesions in India, evidence from other sources indicates that diet may modify risk. This case-control study was designed to minimize a variety of biases in its attempt to investigate the relation between diet and oral precancerous lesions.In a house-to-house survey of 5056 tobacco users in a rural area of Ernakulam district in Kerala, India, 226 individuals (44 females and 182 males) were found to have precancerous lesions (cases), which in 4 cases proved to be cancer. From among the examinees, an equal number of controls who were free of oral mucosal lesions and were matched to the cases regarding age (+/-5 years), gender, ward of residence, and use of tobacco also were enrolled. Dietary data were obtained using a customized interviewer-administered food-frequency questionnaire. All subjects and interviewers were blinded to the disease status of the subject.After controlling for tobacco use, intake of fruits, vegetables, and beta-carotene evinced inverse trends in risk (P0.05), with an average reduction of over 10% per quartile of exposure. Associations with certain micronutrients appeared to differ according to gender, with an apparent 20% reduction in risk per mg of zinc consumed per day among men and the suggestion of an increased risk among those women in the lowest quartile of iron intake (an increase of approximately 2.5-fold) and ascorbic acid intake (an increase of approximately 70% increase) compared with other women (P0.10).Consumption of vegetables, fruits, and several micronutrients may inhibit precancerous lesions of the oral cavity.

The potential of p53 protein expression as a marker for determining which oral precancerous lesions may transform to malignancy with time was assessed. We compared the p53 expression in archival formalin-fixed, paraffin-embedded tissues from 22 baseline biopsies of precancerous lesions that transformed to cancer in 4-25 years against that in 68 similar lesions that did not transform over the same time period. Twenty-nine percent of precancers that transformed were p53-positive at baseline, compared to 31% of the biopsies that did not transform to malignancy. When examined by immunohistochemical methods p53 expression failed to detect potential malignant status of oral precancer. Non-specificity of the assay may account for this result but overexpression of p53 due to DNA damage by tobacco/betel-quid in non-progressive lesions needs further study. Nine precancerous lesions became p53-immunoreactive from precancer to cancer. This may suggest p53 overexpression peaks close to the time of transition from precancer to cancer rather than early in the natural history of oral precancer.

Oral submucous fibrosis (OSF) is a high risk precancerous condition, predominantly affecting Indians. Consumption of chilli was hypothesized as an etiologic factor on the basis of ecological observations and a solitary animal experimental study. Subsequent epidemiologic studies that included case-series reports, large cross-sectional surveys, case-control studies, cohort and intervention studies have identified areca nut as the major etiologic agent. Tissue-culture studies involving human fibroblasts, areca nut extracts and areca nut alkaloids supported this etiologic hypothesis by showing fibroblastic proliferation and increased collagen formation. Currently, the role of genetic susceptibility and that of autoimmunity are receiving attention. The influence of nutritional factors, if any, remains unclear.

The term oral cancer refers to all malignancies that arise in the oral cavity. Squamous cell carcinoma, however, is the most common, accounting for well over 90%. In this paper the term oral cancer is used to describe squamous cell carcinoma comprising ICD (9th revision) site groups 140, 141, 143–145. Oral cancer is one of the ten most common cancers globally (WHO 1984). Its distribution, however, varies from one geographic area to another. It ranks 6th and 9th among men and women in North America while it ranks 1st and 3rd in middle to south Asia (Parkin et al. 1984).

Incidence of oral submucous fibrosis was calculated from a 10-yr prospective intervention study of 12,212 individuals with a strong component of health education on tobacco and area nut chewing. Based on 11 new cases among 6341 chewers, the annual incidence was 8.0 per 100,000 among men and 29.0 for women. An earlier 10-yr follow-up study, with no intervention component, served as control. Based on 11 new cases among 3,809 chewers, the annual incidence was 21.3 per 100,000 for men and 45.7 for women controls. Although the decrease in the incidence in the intervention cohort was not statistically significant due to small number of cases, the results underscored the causal role of areca nut chewing and indicated the potential for primary prevention of oral submucous fibrosis.

The habit of chewing tobacco along with lime in the canine-premolar region of the mandibular groove is widespread (28%) in the rural population of Maharashtra, India. Among individuals with this habit, a thick yellowish-white-to-brown lesion was observed at the site of placement of the mixture. Unlike leukoplakia, this lesion could be scraped off. The prevalence of this lesion among 101,761 Maharashtrian villagers was 2.9% which is four times more common than leukoplakia (0.67%). It is surmised that this particular lesion among the tabacco-lime users is a specific entity with consistent histological features. The diagnosis should be made on the basis of history, clinical features, and consistent histological picture.

The yearly incidence of submucous fibrosis per 100,000 person-years was found to be 9 for males and 20 for females over a 10-year period in the Ernakulam district of Kerala, South India. In the same area possible early cases of submucous fibrosis, under the clinical diagnosis of leukoplakia and lichen planus, showed the typical histologic features of the disease.

– The occurrence in oral submucous fibrosis of small raised blue spots has not been reported. This feature was observed in nine (22%) of 40 submucous fibrosis cases diagnosed in the Ernakulam district, Kerala, India. None of the patients complained of bleeding from the spots or from elsewhere, nor was there any history of systemic disorders. Histologically, the lesions could be explained by juxtaepithelial, endorthelial-lined luminae containing erythrocytes and the presence of juxta- and intraepithclial petechial homorrhages.

A cohort of 12,212 tobacco users was followed up annually to assess malignant potential of oral precancerous lesions in the Ernakulam district in Kerala, India. A total of 19 new oral cancers were diagnosed over a period of 8 years, and 15 (79%) of these arose from some preexisting precancerous lesion or condition. Nodular leukoplakia showed highest rate of malignant transformation (16% per year) as six of 13 nodular leukoplakia underwent malignant transformation over a mean follow-up period of 2.8 years. The relative risk (3243.2) compared with individuals with tobacco habits but without any precancerous oral lesion was also the highest for nodular leukoplakia. In addition, nodular leukoplakia was associated with submucous fibrosis in two patients, which progressed to oral cancer and was the clinical diagnosis for four lesions that turned out to be malignant on histopathologic examination. Nodular appearance was noted in two other precursor lesions as well. Thus, 14 of 19 oral cancers (74%) were either preceded by nodular leukoplakia and with lesions showing a distinct nodular appearance, or had the clinical appearance of nodular leukoplakia.

The occurrence of central papillary atrophy of the tongue among tobacco users, its clinical characteristics and the long term behavior in relation to changes in tobacco use was studied in 182 individuals in Ernakulam district, Kerala, India. Almost all (98%) lesions occurred among bidi smokers. Clinically, about 31% occurred in combination with bidi smoking associated lesions such as palatal erythema (14%), leukoplakia (8%) or both (3%). Histologic evaluation in 12 biopsies using single PAS stained sections showed candidal hyphae in 67%. A 10-yr follow-up (mean: 6.7 yr) of the 182 lesions showed that the regression was highest (87%) among those who stopped their smoking habit and persistence among those who did not reduce or stop their smoking habits. The findings from this study confirm a strong link between bidi smoking and central papillary atrophy of the tongue in rural Indian populations.

The malignant potential of oral lichen planus was assessed on the basis of observations in 722 patients found among 27,599 individuals examined in various epidemiologic studies in Kerala, Ernakulam district, India. Seven hundred and two patients with oral lichen planus were re-examined annually over a 10-year period with a mean observation period of 5.1 years. Most of the lesions (93%) were observed among tobacco users. Carcinoma developed in 3 (0.4%) patients with oral lichen planus. Clinically, all 3 had atrophic components in their lesions, and all were tobacco users. The relative risk of a lichen planus developing oral cancer compared to a tobacco user was estimated as 3.3. However, this relative risk was not significant. Histologically, 74% of the 94 biopsies from oral lichen planus showed epithelial atrophy. Two of the 3 in whom cancer developed also showed epithelial atrophy. It is felt that epithelial atrophy probably renders the mucosa more vulnerable to the carcinogenic action of tobacco. Although this study could not confirm the precancerous nature of this disease with a high degree of certainty, the disease did not appear to be innocuous either.

Regional variations in the characteristics of submucous fibrosis were studied in two districts in India. In Pune district this condition involved soft palate, uvula and retromolar areas significantly more often than in Ernakulam district. The tongue, floor of the mouth and the hard palate were not involved in Pune. The age of the patients in Pune district was lower than in Ernakulam district. Associated oral cancer, leukoplakia and petechiae were observed solely among patients in Ernakulam. The most important etiologic factor for submucous fibrosis is the chewing of areca nut, and in both areas studied all patients chewed areca nut. In Pune, cured areca nut without other ingredients was chewed by 66% and in Ernakulam, raw areca nut was chewed as an ingredient of pan with tobacco by 100%. Thus in Ernakulam, the juice and the quid were mostly spat out, whereas in Pune they were swallowed. The regional variations in the characteristics of submucous fibrosis could be related to the differences in the areca nut chewing habit between the two areas.

In a house-to-house survey in South India, comprising 10,000 villagers, the age-adjusted incidence rate per 1,000 person-years for oral lichen planus was found to be 2.1 for males and 2.5 for females, based upon a 10-year follow-up study. The highest incidence was in the age group 55-64 for males and 45-54 for females. The age-adjusted relative risk was higher for the 'chewing habits' group (6.2) than for the 'smoking habit' group (2.2). The combined effect of the two habits appeared to be multiplicative; the age-adjusted relative risk for the mixed habit group being 13.7.

Sixty-six patients with oral submucous fibrosis were followed-up for a period of 17 yr (median observation 10 yr) in Ernakulam District, Kerala, India. Oral cancer developed in five (7.6%) patients. The malignant transformation rate in the same sample was 4.5% over a 15-yr observation period (median 8 yr). These findings impart a high degree of malignant potential to this condition.

In a house-to-house survey, 36 471 tobacco chewers and smokers were selected from the rural population in three areas of India. These individuals were interviewed for their tobacco habits and examined for the presence of oral leukoplakia and other precancerous lesions, first in a baseline survey, and then annually over a 5-year period. By personal advice and via the mass media they were encouraged to give up their tobacco habits. The follow-up rate was 97%. The control cohort was provided by the first 5-year results from a 10-year follow-up study conducted earlier in the same areas with the same methodology but on different individuals without any educational intervention. In Ernakulam district (Kerala) and Srikakulam district (Andhra) substantially more people stopped their tobacco habit and reduced the frequency of tobacco use in the intervention cohort than in the control cohort; in Bhavnagar district (Gujarat) the intervention group showed only a slightly higher proportion stopping their tobacco habits and no difference in the proportion reducing them. The 5-year age-adjusted incidence rate of leukoplakia in Ernakulam district was 11.4 in the intervention group versus 47.8 among men, and 5.8 versus 33.0 among women; and for palatal lesions in Srikakulam district the corresponding figures were 59.8 versus 260.8 among men and 289.5 versus 489.5 among women. In Bhavnagar the incidence rate of leukoplakia did not differ between the cohorts. Since most oral cancers are preceded by precancerous lesions, education on tobacco habits should be a feasible and effective approach to primary prevention of oral cancer.

In a house-to-house screening survey, 12,212 tobacco chewers and smokers were selected from the rural population in the Ernakulam district, Kerala state, India. These individuals were interviewed for their tobacco habits and examined for the presence of oral cancer and precancerous lesions, first in a baseline survey, and then annually, over a five-year period. They were educated using personal and mass media communication to give up their tobacco habits. The control group was provided from the results of the first five years of a 10-year follow-up study conducted earlier by the authors in the same area with the same methodology but on different individuals without any educational intervention. The stoppage of the tobacco habit was substantially higher in the intervention group (9.4%) compared to the control group (3.2%). A logistic regression analysis showed that the behavioural intervention was helpful to all categories of individuals, however, the effect was different for different categories: intervention was more helpful to men, chewers, and those with a long duration of the habit. These individuals rarely quit their habit without intervention.

A cohort of 12,212 tobacco users was followed up annually to assess malignant potential of oral precancerous lesions in the Ernakulam district in Kerala, India. A total of 19 new oral cancers were diagnosed over a period of 8 years, and 15 (79%) of these arose from some preexisting precancerous lesion or condition. Nodular leukoplakia showed highest rate of malignant transformation (16% per year) as six of 13 nodular leukoplakia underwent malignant transformation over a mean follow-up period of 2.8 years. The relative risk (3243.2) compared with individuals with tobacco habits but without any precancerous oral lesion was also the highest for nodular leukoplakia. In addition, nodular leukoplakia was associated with submucous fibrosis in two patients, which progressed to oral cancer and was the clinical diagnosis for four lesions that turned out to be malignant on histopathologic examination. Nodular appearance was noted in two other precursor lesions as well. Thus, 14 of 19 oral cancers (74%) were either preceded by nodular leukoplakia and with lesions showing a distinct nodular appearance, or had the clinical appearance of nodular leukoplakia.

The occurrence of tuberous sclerosis among Indians has not been reported earlier. In the Ernakulam District, Kerala, in a kindred of 27, seven cases with oro-facial or facial lesions of tuberous sclerosis were observed. None of the individuals was mentally retarded, nor was there any history of systemic anomalies. The cases in this series possibly represent an incomplete form (Forme frustes) of the syndrome. The pedigree in the present material supports the autosomal dominant inheritance.

In the rural health care delivery system in India, basic health workers (BHW) go house-to-house to help in the preventive and therapeutic measures of certain diseases. Some 53 BHW were trained by the dentists of the research team for examining the oral cavity of high-risk individuals and categorizing them into normals or those with referable or nonreferable lesions. Referable lesions comprised nodular leukoplakia, submucous fibrosis, and ulcers and growths suggestive of oral cancer. In a 1-year period, 39,331 high-risk individuals were examined by BHW and 523 (1.3%) were referred for further diagnosis. Some 72% arrived at the referral center and 20 oral cancers were confirmed among these individuals. Reexamination in the field by the dentists was conducted for 5% of the sample to obtain sensitivity and specificity estimates of BHW diagnosis. The findings indicate that incorporation of an oral cancer detection program in the existing health care infrastructure is feasible and beneficial.