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Application of case study and role-playing in forensic chemistry education. Dr Renata Wietecha-Posłuszny Laboratory for Forensic Chemistry, Department of Analytical Chemistry, Jagiellonian University, Krakow. Way we use didactic method?. tactic of educational process;
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Application of case study and role-playing in forensic chemistry education Dr Renata Wietecha-Posłuszny Laboratory for Forensic Chemistry, Department of Analytical Chemistry, Jagiellonian University, Krakow
Way we use didactic method? • tactic of educational process; • making students an active element ofeducational process by motivating them to participate to curricular and extracurricular activities; • find solution to cognition tasks and problems creating an alliance professor-student; • develop logical and factual thinking at same rate; • determination of professor as moderator and observer during educational process; • to open paths and possibilities of discovering and understanding reality; research technical possibilities; develop cultural background; etc. FINAL Tempus-EDUFORMARK WORKSHOP, Skopje,15.02.2010
Didactic techniques • Case study • Role-playing • Group working • Learning in Context • Brainstorming • Problems of Base Learning • Projects etc. FINAL Tempus-EDUFORMARK WORKSHOP, Skopje,15.02.2010 3
Laboratory Class of Forensic Chemistry at Jagiellonian University • The class is conducted at the Faculty of Chemistry of the Jagiellonian University within the course “Chemical investigations in criminalistics and toxicology” • The duration of classes comprises of two teaching/learning units, 7.5 lesson hrs each (1.5 hrs - seminary and 6 hrs – laboratory class). • Classes are for four-year students of chemistry, forensic chemistry panel • the group consists of six students FINAL Tempus-EDUFORMARK WORKSHOP, Skopje,15.02.2010
Forensic Laboratory Class - example Title:Application of the AFS method to post-mortem examination of acute toxic metal poisoning FINAL Tempus-EDUFORMARK WORKSHOP, Skopje,15.02.2010
Forensic Laboratory Class - example • Aims: • To introduce students to every step of the toxicological expertises and the way of writing expert opinions • To explain the chemical and physical background of atomic fluorescence spectrometry and digestion technique FINAL Tempus-EDUFORMARK WORKSHOP, Skopje,15.02.2010
Steps of laboratory class The seminar part: (i.e. presentation and discussion) • films or short newspaper articles (case background) - short crime stories or unsolved crimes • material evidences The experimental part: • preparing of material evidences (working in small teams) - digestion of samples • analysis of biological and another samples by HG-AFS technique The expert’s report FINAL Tempus-EDUFORMARK WORKSHOP, Skopje,15.02.2010
Part of seminar Presentation of the topic and discussion in the seminar room X – files - Presentation of case background Discussion about the theoretical topics and brainstorming Decision about: essential analyses, possible methods, available time and equipment Fails and material evidence - Instruction and reporting officer’s narrative Decision of the prosecutor to appoint expert FINAL Tempus-EDUFORMARK WORKSHOP, Skopje,15.02.2010
Sort of poisons • famous historical poison - ”Poison of King” or „Aqua Tofana" ; no smell, no taste and easy soluble in water • strong toxic effect: (Seńczuk 1999) • toxic dose 70-300 mg (WHO 1993) • symptoms of arsenic poisoning include: violent stomach pains, vomiting and delirium, • cancer disease (Bescheri in 1993) FINAL Tempus-EDUFORMARK WORKSHOP, Skopje,15.02.2010 9
Famous cases • prominent people throughout history (Napoleon Bonaparte, George III of the United Kingdom • tricky housewife or husbands Maria Capelle - Lafarge"Maria Lafarge" FINAL Tempus-EDUFORMARK WORKSHOP, Skopje,15.02.2010 10
Seminar part - Case studies I’m lost. It is the end! Fatal arsenic poisoning • Two men visit the bank. They have a paper allowing them to take 1,500,000 zlotys (215,000 GBP) • After short chasing, police arrest suspects and recover the money • Few minutes later, a clerk looks carefully to the document, they gave him. Some writings look suspicious and he decides to call the police • But both robbers, justbefore beingclapped in irons, eat portions of white powder. Soon, in the local brig, they get sick and die despite the medical treatment FINAL Tempus-EDUFORMARK WORKSHOP, Skopje,15.02.2010
Seminar part - Case studies Fatal selenium poisoning • A 22-year-old student of biology was carrying out experiments for her Master’s thesis. Suddenly she went to the toilet and vomited violently. She had severe diarrhea and complained of abdominal pains. • After admission to hospital, she developed cardiovascular failure, and therefore, was subjected to intensive treatment, moreover doctors noticed a strange smell from her whole body. What is wrong with this experiment?! Ohh…I hated it! • Just before passing away, she had confessed that she had ingested about 20 ml of sodium tetraoxoselenate(VI) with suicidal intent. FINAL Tempus-EDUFORMARK WORKSHOP, Skopje,15.02.2010
Decision of the prosecutor to appoint the expert FINAL Tempus-EDUFORMARK WORKSHOP, Skopje,15.02.2010 13
Material evidence • the following items are taken as evidence from the crime scene (e.g. the bottle of wine, the glass and its contents etc.) • autopsy material (blood, urine, hair, section of internal organs: liver, lung, brain etc.) FINAL Tempus-EDUFORMARK WORKSHOP, Skopje,15.02.2010 14
Steps in hair sample preparations for toxicological analysis Pre - analytical Analysis of washings I step Decontamination Segmentation II step III step Weighing of hair segments and fragmentation Sample preparation For drugs For elements IV step Matrix destruction Extraction or digestion of hair matrix Clean –up of hair extract Pre-test by immunoassay Analyte enrichment V step AFS or AAS or ICP-MS GC-MS or GC-MS-MS or LC-MS-MS IV step
Principle of Atomic Fluorescence Spectrometry Atomic Fluorescence Spectra Ei Excitation Process Light Energy E=hn Eo De-Excitation Process FINAL Tempus-EDUFORMARK WORKSHOP, Skopje,15.02.2010
Experimental part - Mysterious Suicides • Preparing of material evidences FINAL Tempus-EDUFORMARK WORKSHOP, Skopje,15.02.2010
Experimental part - Mysterious Suicides • Analysing of all samples, obtaining data FINAL Tempus-EDUFORMARK WORKSHOP, Skopje,15.02.2010
Parts of expert opinion • introduction - description of all material evidences • body - an account of the analysis steps and the obtained results • Conclusion - answer to proposed questions from prosecutor FINAL Tempus-EDUFORMARK WORKSHOP, Skopje,15.02.2010 19
Like an Expert - Role-plays Team prepares its exercise report according to rules of the expert opinion for trial purposes. • Description of evidence • Account ofmeasurements • Answers to prosecutor’s questions • Conclusions Case Closed! prawo.gazetaprawna.pl FINAL Tempus-EDUFORMARK WORKSHOP, Skopje,15.02.2010
Laboratory Class of Forensic Chemistry December 2009 – students from Macedonia FINAL Tempus-EDUFORMARK WORKSHOP, Skopje,15.02.2010 21
References • Seńczuk W. [red.], Toksykologia, PZWL, Warszawa, 1999, 437-509. • Kościelniak P., Problematyka kalibracji w analizie chemicznej, Chemia Środowiska cz.2, 277-301. • Namieśnik J.[red.], Przygotowanie próbek środowiskowych do analizy, Wydawnictwo Naukowo-Techniczne Warszawa, 1999, 56-67. • Szczepaniak W.[red.], Metody instrumentalne w analizie chemicznej, PWN, Warszawa 2004, 22-29. • Walas S., Atomowa spektrometria fluorescencyjna (ASF) – cz I i II.– Analityka, nr.: 2 i 3, 2002 odpowiednio 10-11 oraz 9-12. • Additional • 1.Klewska A.., Przygotowanie materiału biologicznego do oznaczania śladów metali, • Z Zagadnień Kryminalistyki, 3, 1968, 62-67. • 2.Stryer L., Biochemia, PWN, Warszawa, 2003, 280-360 • 3.Katz S. H., Chatt A. [red.], Hair Analysis – Applications in the Biomedical and Environmental Sciences, VCH, Weinheim 1988. • 4.Sanz M., Romero F., Romero C., Selenium and cancer: some nutritional aspects, Review article, Nutrition, 16, 2000, 376-383 FINAL Tempus-EDUFORMARK WORKSHOP, Skopje,15.02.2010
Conclusions • Using the variety didactic method help to improve student practical skills such as: observation, interpretation, problem solving, team work, experiment design, data maintenance and analysis, communication and presentation, laboratory and interpersonal ability, leadership capabilities etc. • The form of laboratory class help to increase students’ interest and motivation • Obtained skills during experimental work are valuable in the future carrier as a forensic expert FINAL Tempus-EDUFORMARK WORKSHOP, Skopje,15.02.2010
Thank you for your attention FINAL Tempus-EDUFORMARK WORKSHOP, Skopje,15.02.2010 24
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