Ore Grade Reconciliation Techniques – A Review

The purpose of this study is to determine the effectiveness of instructional strategies administered by primary school Science and Social Sciences teachers based on the opinions of students, and to identify if there is any difference between teachers of the two courses in terms of the level that they carry out these activities. This study is descriptive in nature. 7th grade students at primary schools in Melikgazi, Kayseri, during the spring term of 2004-2005 formed the research universe of the study. There were 87 primary schools in Melikgazi when the study was conducted. Ten primary schools were identified by stratification method, and 7th grade students in one of the classes of each school were chosen randomly and assigned as the sample group of the study. There are totally 300 students (30 students from each school) in the sample. The findings of this study reveal that strategies in the instruction step of a lesson are not applied effectively. Most of the activities were found to be conducted occasionally in both groups. According to the results, teachers of Social Sciences were identified to be more productive and effective than those of Science course in the following areas: providing reinforcement and prompting, being understanding and affectionate, using course-related tools and instruments, and creating a classroom environment where students participate actively. Summary Lesson plan consists of three interwoven steps; preparation before the lesson, planning and administering the lesson, and follow-up activities. Effective teaching is based on a well-developed plan, a well-managed classroom, and an effective presentation. Making necessary preparations and planning before a lesson may contribute a lot to success of students. A teacher has to get prepared before the lesson and has to plan the presentation, instruction, and assessment activities of the lesson in order to maintain students' interest, to maintain participation, and to sustain students' motivation at a high level. Therefore, it is vital for teachers both to be informed about instructional strategies and to have related skills to carry out these strategies. Presentation, instruction, and assessment activities within a lesson plan display different characteristics and have distinct steps. Instructional strategies are more important in nature since this is the phase when teaching is administered and learning takes place. All the definitions, concepts, rules, formulae, and explanations are delivered to students during this step. The information flow in this phase is from simple to complex, from concrete to abstract, from known to unknown, and from immediate to far. Teachers should be aware of the stimuli that affect students' learning and should use them when needed. During the instruction step, teachers should create a setting that increases interaction among students, trains them on cooperation, and improve their self-confidence; should provide various sources of information; should encourage students to learn by discovering; and should make use of methods and instruments that assess students' performance. The purpose of this study is to determine the effectiveness of instructional strategies administered by primary school Science and Social Sciences teachers based on the opinions of students, and to identify if there is any difference between teachers of the two courses in terms of the level that they carry out these strategies. Since a survey/questionnaire is utilized for the above purpose, this study is descriptive in nature. Method Sample 7th grade students at primary schools in Melikgazi, Kayseri, during the spring term of 2004-2005 formed the research universe of the study. There were 87 primary schools in Melikgazi when the study was conducted. Ten primary schools were identified by stratification method, and 7th grade students in one of the classes of each school were chosen randomly and assigned as the sample group of the study. There are totally 300 students (30 students from each school) in the sample. Researchers visited all these schools and distributed the questionnaire forms personally. Then, students filled out the forms under the supervision of researchers. Instrument The first draft of the questionnaire used in this study was developed in accordance with the related literature. Afterwards, the draft version was analyzed by experts in educational sciences and teachers lecturing Science and Social Science in terms of its content validity, and all necessary corrections were completed. Then, the questionnaire form was applied to a group of students to see if the statements were clear or not. After all the revision efforts, the questionnaire including 21 items about both lessons was given its final form. Cronbach Alpha Reliability coefficient of the questionnaire was found to be 0.86. Findings and discussion The findings of this study reveal that strategies in the instruction step of a lesson are not applied effectively. Most of the strategies were found to be conducted occasionally in both groups. According to the results, teachers of Social Sciences were identified to be more productive and effective than those of Science course in the following areas: providing reinforcement and prompting, being understanding and affectionate, using course-related tools and instruments, and creating a classroom environment where students can participate actively. On the other hand, teachers of Science course were assessed as more able in encouraging whole-class participation. Teachers may make use of various teaching techniques and methods in the classroom providing that they are informed about instructional strategies that should be taken into consideration during both planning and administering steps of a lesson and about different instructional methods. So at certain intervals, teachers may get feedback from students regarding their own behaviors and may make necessary amendments accordingly. Teacher training institutions and programs may be improved in terms of equipment and service provided for students. Teachers might be guided to attend in-service training programs designed to compensate for their insufficiencies concerning preparation, administration, and assessment of a lesson, and to inform them about innovations in teaching.

Abstract. This research aims to (1) Analyze the chemistry handbooks used in the vocational school of Pharmacy in North Sumatra, (2) Develop a sequence of chemical material suitable to grade X semester I and systematically according to KTSP of Pharmacy Vocational School, (3) Knowing what chemical materials worth and the right to be taught in Pharmacy vocational school grade X semester I so that learning is more systematic and easily understood by BSNP students in learning, (4) Developing the chemistry handbook for grade X semester I Pharmacy Vocational School appropriate with KTSP, and (5) Knowing the opinion of teachers of chemistry at Pharmacy Vocational School on the development of standard chemistry handbook of grade X semester I. Sample in this study are two publishers of chemistry handbooks used in grade X semester I of the most widely used in Pharmacy Vocational School in North Sumatera, has graduated from the book center, and marketed nationally and four vocational school chemistry teacher used grade X Pharmaceuticals as a respondent and has teaching experience in grade X Pharmacy Vocational School for a minimum of two years and a minimum education is bachelor degree (S1). This is a research development using qualitative data described by using the time sentence by emphasizing the documentary technique. This research instrument is a questionnaire with a book containing sheets of the feasibility of the indicators derived from the assessment of National Education Standards Agency (BSNP) in 2006, later identified occurrence for each book. Furthermore it is developing chemistry handbook for grade X semester I Pharmaceuticals appropriate vocational curriculum, which will be assessed by the respondent chemistry teachers of Pharmacy Vocational School. The assessment results of validation between the average range to determine whether or not worthy of the book used in grade X semester I of Pharmacy Vocational School. The results of the feasibility analysis of the contents of the handbooks most widely used chemical in the first semester of the grade X is obtained percentage Pharmacy Vocational School: books A, and B are, respectively 51.89% and 76.01%. Validation range obtained in the proposed grade X semester I of chemical materials Pharmacy Vocational School is 3.6 means that the proposal put forward appropriate materials are used in the development of chemistry handbooks for grade X semester I Pharmacy Vocational School. Assessment chemistry handbook for grade X semester I Pharmacy Vocational School on the feasibility of content, language, and presentation by chemistry teacher of Pharmacy Vocational School respondents obtained an average yield of the range of validation in order are 3,31; 3,52, and 3,51. Validation of the overall range obtained from the four respondents chemistry teacher of Pharmacy Vocational School is 3.45, this means that the Chemistry Handbook for Grade X Semester I Pharmacy Vocational School According With KTSP is valid and does not need to be revised again and have been feasible to use in chemistry learning in Pharmacy Vocational School. Keywords: Chemistry Handbook, Pharmacy Vocational School, Analysis, Development, KTSP

In order to distinguish the grades of breast pain with a quantitative index, the detection and pain thresholds were measured with the technique of TSA (Thermal Sensory Analysis) on patients with breast pain. We aimed to explore whether TSA could be used to predicate the degree of breast pain as an objective indicator or not. Thirtytwo female outpatients with breast pain were included in the study by inclusion criteria. A total of sixtyfour breasts were measured. The cold pain threshold (CPT), cold detection threshold (CDT), warm detection threshold (WDT) and heat pain threshold (HPT) were measured at the following five points of both sides: neck, shoulder, axilla, back and super ior lateral quadrant of breast. The sixtyfour breasts were devided into three groups: Group A consisted of 29 breasts that have breast pain grade from 0 to 1 (No pain at that time); Group B consisted of 20 breasts that have breast pain grade from 2 to 4 (Pain exist, but participant can’t give it an explicit score); Group C consisted of 15 breasts that have breast pain grade from 5 to 7. Statistic analysis was performed by SPSS 20.0 to compare the means and SD. Variance for each threshold at each site was expressed as Coefficient of Variation percentage (CV%), using the standard deviation (SD) divided by the meanx100. On every sites, group B has the highest value of WDT and HPT. And expect the site of axilla, group C has higher values than group A of WDT and HPT. On the site of breast, the values of CPT and CDT have the trend to increase from group A to group C. But the differences in groups were without statistically significant differences (p>0.2). The CV% of HPT and WDT are lowest and near to each other, and CPT has the highest value of CV%. Breast pain can not only reduce the sensibility of warm detection and heat pain of breast, but also the sites close to breast. Oppositely, breast pain can enhance the sensibility of cold detection and cold pain of breast. But C PT has the highest value of CV%, this may means CPT has poor reliability due to wide variance.

This study is a classroom action research (CAR) on utilizing animation video in teaching vocabulary to young learners. Therefore, the objective of this study is to find whether the use of animation video can improve vocabulary mastery of grade IV students of SD Negeri 2 Baruga. This research is conducted within two cycles in which each cycle consisted of three meetings. Either first cycle or second cycle consisted of planning, action, observation/evaluation, and reflection. The subject of this study was students at grade IV of SD Negeri 2 Baruga. A number of the students in the class were 30 with 8 male and 22 female. Then, the instruments were used in this study include observation sheet of teacher’s and students’ activity, and vocabulary test. The researcher found that teaching English by using animation video can improve students’ vocabulary at grade IV of SD Negeri 2 Baruga. The improvement could be seen in the result of students’ achievement after conducting this study was 93 % proved that it achieved classical achievement. Moreover, percentage of teacher’s and student’s activity also achieved 82.14% and 68.70%. On other words, the students’ vocabulary at grade IV of SD Negeri 2 Baruga improved by using animation video. Keywords: Animation video, Vocabulary and Young Learner

This U.S. Geological Survey (USGS) data release provides the descriptions of 11 U.S. sites that include mineral regions, mines, and mineral occurrences that contain enrichments of niobium (Nb). To be included in this data release, a site must have a contained resource and (or) past production of Nb metal greater than 10,000 metric tons, which was the approximate consumption of Nb in the U.S. in 2019 (U.S. Geological Survey, 2020). Sites in this dataset occur in Alaska, Arkansas, Colorado, Nebraska, and Texas. Niobium primarily occurs in oxide minerals of the pyrochlore group, which are most commonly found in carbonatites and alkaline granite-syenite complexes. Globally, the largest Nb deposits occur in Brazil and Canada. In Brazil, the Barreiro carbonatite complex hosts the Araxa deposit that contains more than 460 million metric tons of ore with an average grade of 2.48 percent Nb2O5 (Schulz and others, 2017). The world’s leading producer of Nb outside of Brazil is the Niobec Mine in Quebec, Canada. The Niobec deposit occurs in the Saint-Honore carbonatite complex, where pyrochlore is the main niobium-bearing mineral; the ore body contains more than 400 million metric tons with an average grade of 0.42 percent Nb2O5 (Schulz and others, 2017). In comparison, the largest known Nb deposit in the U.S. is the Iron Hill deposit in Colorado, which has been prospected for titanium, Nb, rare earth elements and thorium. There are no current U.S. producers of Nb, but the Elk Creek project in Nebraska is in the furthest stage of development. If Elk Creek comes online, it will be the first recorded producer of Nb in the U.S. since the 1950s. Niobium is necessary for strategic, consumer, and commercial applications. The primary use for Nb is for the production of high strength steel alloys used in pipelines, transportation infrastructure, and structural applications (Schulz and others, 2017). As of 2019, the U.S. maintains a history of being 100 percent net import reliant on Nb from countries, such as Brazil and Canada. Niobium is imported to the U.S. as Nb minerals, oxides, and ferroniobium (U.S. Geological Survey, 2020). The entries and descriptions in the database were derived from published papers, reports, data, and internet documents representing a variety of sources, including geologic and exploration studies described in State, Federal, and industry reports. Resources extracted from older sources might not be compliant with current rules and guidelines in minerals industry standards, such as National Instrument 43-101 (NI 43-101). The inclusion of a Nb mineral deposit in this database is not meant to imply that the deposit is currently economic. Rather, these deposits were included to capture the characteristics of the largest Nb deposits in the United States. Inclusion of material in the database is for descriptive purposes only and does not imply endorsement by the U.S. Government. The authors welcome additional published information in order to continually update and refine this dataset. Schulz, K.J., Piatak, N.M., and Papp, J.F., 2017, Niobium and tantalum, chap. M of Schulz, K.J., DeYoung, J.H., Jr., Seal, R.R., II, and Bradley, D.C., eds., Critical mineral resources of the United States—Economic and environmental geology and prospects for future supply: U.S. Geological Survey Professional Paper 1802, p. M1–M34, https://doi.org/10.3133/pp1802M. U.S. Geological Survey, 2020, Mineral commodity summaries 2020: U.S. Geological Survey, 200 p., https://doi.org/10.3133/mcs2020.

Steel Supply Chain using Direct Reduction Method (DRI) includes all activities from supplying iron ore, concentrate, pellet, sponge iron and finally delivering the ultimate commodities to the steel production units. Different complexities and uncertainties of supply chains; such as limitation of suppliers and customers, variety of technical & economical option etc, cause to have a proper management of the supply chain. In this study, a system dynamic approach was used to simulate a dual-echelon of steel supply chain (iron ore-concentrate & concentrate-pellet). Hence, not only this study defines the influence of qualitative and quantitative variables in supply chain management (SCM), but also the interaction between variables and their feedbacks. This model is implemented in a steel complex using DRI in Iran in which various scenarios are analyzed. The simulation results show that an increase of 2% in iron ore grade results in 3.35% rise in total pellet production. Also, simultaneously increase of 2% in ore grade, 5% in production rate and 2% in conversion ratio results in 5.85% in total pellet production.

Introduction: the aim of our study was to perform a longitudinal follow-up in patients with anorectal malformations(ARMs) in order to determine the anorectal function problems and help to solve them.Material and Methods: This study included 262 patients with ARM who were operated between 2006 until 2013.Children whose definitive reconstruction was performed at another hospital and underwent reoperation in our center were excluded. Patients who expired or did not come for follow-up were not included in the study either. Bowel function was prospectively assessed by using a questionnaire answered by the children’s parents. supplementary bowel management with enemas, laxatives and the use of diapers were documented as well.Results: Interviews were completed in 242 children, ages ranging from 3 to 10 years. More than thirty seven (37.7%) patients had constipation.32.5% Grade 1 (controllable by altering in diet), 54.3% Grade 2 (requiring laxatives) and 13.2% Grade 3(opposed to stool softeners and diet).18.6% of patients had fecal soiling, 31.5% Grade 1: infrequently (once or twice for every week), 24% Grade 2: daily (no community difficulty) and 44.5% Grade 3: Constant (social problem).Conclusion: In the present study several bowel function problemswere found in ARM children. physicians who perform the definitive operation on anorectal malformations should notloose follow up of patients as they grow upbecause they may present with great troubles during their adolescence.

Both the Evidence Based Medicine (EBM) and Person Centered Healthcare (PCH) movements recognize that decisions on how to manage the care of individual patients in the clinical encounter require more than simple application of those therapies shown effective in a clinical trial. GRADE, a popular framework for developing clinical recommendations, identifies patient “values and preferences” as an important consideration in clinical decision making and a component in determining a clinical recommendation and its strength. However, how patient “values and preferences” are conceptualized in GRADE are problematic if one believes the individual patient’s care should be aligned with her values and preferences. GRADE focuses on “typical” patient “values and preferences” in the process of determining the recommendation. There is no guarantee that the values and preferences of the typical patient will represent that of the individual patient in the clinical encounter. Furthermore, the strength of the recommendation (“strong” vs . “weak”) appears to impact how much patient engagement is warranted (under GRADE), which affects the extent to which information on the “values and preferences” of the individual patient will be sought out or revealed in the clinical encounter. The issues raised in this paper stem from a lack of an underlying theory and empirical support to explain why certain elements have been included in the framework, and others not. A failure to clearly define, operationalize, and measure a patient’s “values and preferences” may limit the value of GRADE derived recommendations and subsequent clinical practice guidelines in managing the care of individual patients consistent with PCH.

Biochemical markers for early detection of superficial pressure ulcers

Objective To understand the situation of varicella prevalence and vaccination of susceptible population in Longhua District, and to provide reference for the varicella immunization program. Methods A total of 23 706 children from 30 childcare facilities and primary schools in 6 streets were randomly selected throughout the Longhua District. Date on age, grade, recent year and dosage of vaccination, varicella incidence, the overview of vaccination were collected and analyzed. Results The rate of vaccination in childcare facilities and primary schools was 86.01%, including 55.61% of 1 dose and 30.41% of 2 doses of vaccine. The differences of rate vaccination rate between the childcare facilities and primary schools had statistical significance ( χ 2 = 154.95, P < 0.05). Rate of no-vaccination, 1 dose vaccination and 2 doses vaccination across 6 streets differed significantly ( χ 2 = 146.09, 103.93, 127.31, 146.09, P <0.05). There was an increasing positive association between grades and attack rate ( χ 2 = 8.65, P <0.05). The differences of attack rate between the childcare facilities and primary schools was of statistical significance ( χ 2 = 478.69, P <0.05). The differences of attack rate in street of no vaccination, 1 dose vaccination and total attack rate showed statistical significance ( χ 2 = 54.49, 74.59, 151.49, P <0.05). There was an increasing linear trend of attack rate of primary school childrenby each year ( χ 2 = 24.28, P <0.05). The attack rate increased with time after 1 dose vaccination, immune protection was obtuined for a longer period time after additional doses of vaccine. Negative association was found between grades and protective efficacy rate of varicella. The protective rate and efficacy index of different doses of vaccine in different grades were correlated ( r = 0.80, 0.63, P <0.05). It was most effective after 1 dose vaccination among children in junior grade in kindergarten and 2 dose vaccination in senior grade. Conclusion After the implementation of vaccination program in Longhua District, the vaccination rate of 2 doses significantly increased, but not for a long time. Varicella vaccine should be included in immunization programme to protect vulnerable populations. 【摘要】目的 了解水疸疫苗预防接种政策实施后,深圳市龙华区水疸髙发人群的疫苗接种及水疸流行现状,为指导当 地制定水疸免疫规划措施提供参考。 方法 采用随机分层整群抽样方法,选择深圳市龙华区 6 个街道 30 所托幼机构及小 学23 706名儿童进行电子问卷调査,对获得的年龄、年级、最近疫苗接种年份、接种剂次、发病情况、发病时疫苗接种情况 等基础数据进行分析。 结果 龙华区托幼及小学儿童水疸疫苗总接种率为86.01%,其中 1 剂次接种率为55.61%, 2 剂次 为30.41%。托幼机构及小学的接种率差异有统计学意义( χ 2 = 154.95, P <0.05)。各街道未接种率、 1 剂次接种率、 2 剂次接 种率、总接种率差异均有统计学意义( χ 2 值分别为146.09,103.93,127.31,146.09, P 值均<0.05)。年级别罹患率与年级的 髙低呈正比( χ 2 趋势 =8.65, P <0.01),托幼机构与小学的罹患率差异有统计学意义( χ 2 =478.69, P <0.05)。各街道未接种罹患 率、 1 剂次罹患率、总罹患率差异均有统计学意义( χ 2 值分别为54.49, 74.59,151.49, P 值均<0.05)。随间隔年份增加小学 儿童罹患率具有线性趋势( χ 2 趋势 =24.28, P <0.05), 1 剂次水疸疫苗接种后间隔时间越长罹患率越髙, 2 剂次疫苗可保证较长 时间的保护效果。疫苗的保护率与年级的髙低呈反比,各年级不同剂次疫苗保护率及效果指数之间的相关性有统计学意 义（ r 值分别为0.80, 0.63, P 值均<0.05)。接种 1 剂次疫苗及 2 剂次疫苗效果最好的分别为小班、大班。 结论 龙华区政 策实施后 2 剂次疫苗接种率明显提升,但未起到持久效果。建议将水疸疫苗纳人免疫规划,以达到保障易感人群目的。

The level of understanding scientific and engineering practices in light of the next generation science standards among preservice student teachers

This study aims to determine the application of cooperative learning models of the Teams Games Tournament (TGT) type on learning to improve student learning outcomes. The subject of this research was the tenth grade students of SMAN 1 Batang Onang. This type of research is Classroom Action Research. The research design used was the Kemmis and Mc model. Taggart which includes the stages of planning, action and observation, and reflection. The data collection instruments used were observation sheets, student activity scale, and LKS. The data analysis technique used is descriptive qualitative and quantitative data analysis. Based on the results of data analysis in the first cycle of meeting I showed an increase in student mathematics learning outcomes. Research Results, namely an increase in student learning outcomes The average grade value when the pre test is only 38.67. The class average value increased by 63 in cycle I. The average grade value in the first cycle still did not meet the KKM set by the school. In the second cycle the average value of the class experienced an increase of 85.33. Classical learning completeness in the first cycle was only 53%. In cycle II classical learning completeness becomes 96%. This shows an increase in students' classical learning completeness by 43%.

During the construction of tunnel, the observational classification of rock mass quality is the most direct method to evaluate the quality of the tunnel face surrounding rock. It is also an important basis for preventing geological disasters in tunnel construction, deciding construction excavation method and supporting measures. The traditional Q method and BQ method of national standard rock mass quality grading evaluation method require on-site and indoor laboratory tests and analysis, which results in the lag time of rock mass quality evaluation, often reduces the construction efficiency, or misses the window time to prevent sudden construction geological disasters. Rapidly and accurately to rock mass quality classification of tunnel face is the primary problem to be solved in observational rock mass classification of highway tunnel during construction period. The artificial intelligence algorithm provides a method to solve the real-time and accurate evaluation of the rock mass of the tunnel. Taking Yanqing-Chongli highway for Beijing Winter Olympic Games as an example, we adopt a method of using photogrammetry and artificial intelligence rock structure parameter to identify working face. In this method, seven index parameters system are established. We use the KNN intelligent algorithm to evaluate the quality of the tunnel rock and select 150 samples from 40 working faces in 8 tunnels for the training and learning. Another 50 samples are selected for rock mass quality evaluation and verification. Compared with the rock mass quality evaluation results of BQ, the accuracy reachs 90%. Conclusions are as follows. (1)KNN method for observational classification of rock mass quality of highway tunnel is a fast and efficient method for observational classification of rock mass quality by using artificial intelligence technology, which can obtain real-time rock mass evaluation results on site. (2)KNN classification method selects seven discriminant indicators, considering the occurrence of rock environment, geological structure, rock structure and other characteristics, and reflecting the operability and applicability of these indicators in the actual engineering. (3)KNN classification method misjudgment rate is very low. It has strong discriminant ability when marking discriminant classification by excluding the influence of artificial factors. This method provides a new way to solve the rock mass grade determination and classification.

Endoscopy is an effective tool for variceal grading, but it is costly, invasive, and not always at hand. The study aimed to assess platelets count and ultrasonographic parameters of portal hypertension as predictors of esophageal grade. This, cross-sectional hospital based study conducted among100 patients with Schistosomal portal hypertension at Ibn Sina Teaching Hospital, Khartoum, Sudan during the period from November 2011 – August 2012. Patients with liver cirrhosis, previous treatment for esophageal varices or on β blockers were not included. Information collected were: socio-demographic data, history of and onset of variceal bleeding, ascites, SchistosomaMansoni Score (SMS), the spleen size, liver span, portal and splenic veins diameter, variceal grade, and platelets count. The ethical committee of the Sudan Medical Specialization Board approved the research and the Statistical Package for Social Sciences (SPSS, version 20, New York) was used for data analysis. Participants (76% males), Mean age (43.9 ± 14 years), liver span, spleen size below the costal margin, and portal vein diameter were, 10.34± 2.01, 6 ± 3.9, and 1.5 cm ± 0.27 cm respectively. Platelets count, SMS, the extent of periportal fibrosis, and portal vein diameter were significant predictors of esophageal grade,(P-value <0.05), while spleen size, portal vein diameter, platelets/spleen index were not. The study concluded that, non-invasive assessment of ultrasonographic parameters (ShistosomaMansoni Score, portal vein diameter, degree of periportal fibrosis) and platelets count could aid the detection of patients with large esophageal varies for the implementation of the needed intervention. The limitation was the small sample size.

Introduction: As contemporary as it looks to young people between 16 and 18 years of age, early sexual activity has its high price. Along with the strong emotions of falling in love, there come unwanted pregnancy and sexually transmitted diseases. These diseases are characterized by diverse clinical symptoms but they have the same mechanism of transmission and spread of infection - sexual contact. The aim of this study is to investigate the awareness of students from 9th to 12 th grade from the Professional School of Natural Sciences - `Acad. N. Obreshkov` - Razgrad of the risks, prevalence and the prevention of STDs and unwanted pregnancy. Materials and Methods: The study covered high-school students from 9th to 12 th grade from the Professional School of Natural Sciences - `Acad. N. Obreshkov` - Razgrad in January 2016. A hundred students participated in the survey. There were 52 girls and 48 boys. A poll with 14 questions was developed for this study - 12 multiple choice questions and 2 open-ended questions. The processing and data analysis used documentary, statistical and graphical methods. Results: Students from the 9 th grade were chosen as the lower end in determining the scope of the study. More than 1/3 (38%) of the students said they had casual sex, which increased significantly in students from 11 th and 12 th grade. Approximately half of the participants (42.10%) said that they were using protection during intercourse. Only 10.50% of all stated that they never used protection. The most commonly used protection was a condom combined with contraceptive drugs or intrauterine devices. Conclusion: The results show that young people are familiar with the basic methods of prevention, not only for pregnancy but also for STDs. The main sources of information for them are the Internet and conversations with parents.