No description available.

No description available.

This report documents the process of designing a laboratory exercise in Fourier analysis at Vetenskapens Hus (House of Science) in Stockholm. The lab is designed for high school students studying science or technical education. It focuses on the physical understanding and mathematical description of sound, in particular music. A model of such a lab is presented in this work; containing a review of the mathematical theory, summary of educational research in the field, descriptions of the design process and of the investigative work that led to the final result. The designed material for the lab includes developed computer programs, visit leader tutorial and description for teachers.

With the advent of the atomic age, a great deal of attention has been given to the effects of radiation of various types on the living organism. Some emphasis was placed also on the particular effects damaging radiation has on the central nervous system. Of particular importance was the dis -covery of the high resistance to irradiation exhibited by the central nervous system, and the observation of a latent period after exposure, during which the individual appears normal, followed by deterioration and death. Explan - ations of this unique reaction have caused some controversy and, currently, one of two theories are supported by most workers: (1) vascular damage is the primary cause of brain damage, precedes it, and causes necrosis; (2) direct damage is caused to nerve tissue by radiation and vascular damage is of secondary importance. Both theories have good supporting evidence as will be reported later.

This master thesis is the documented work of the construction process and testing of a three hour laboratory session in mathematics aimed at high school level students. The purpose of the thesis was to create an interesting laboratory session for the science education center ”The House of Science” that could be used as a part of their regular program directed to schools. The thesis explores the possibilities for how one can construct a laboratory session on the topic ”molecular symmetry” as well as the underlying pedagogical theories used to describe learning processes in creative contexts. A model for such a session is proposed, an evaluation is conducted and its results and implications are appropriately discussed. An important review of the mathematical background of symmetries, group theory and linear representations of finite groups was written and can be found in the appendices.

Knäets artär, arteria (a.) poplitea, kan drabbas av aneurysm, vanligen om personen redan har ett aortaaneurysm. Kärlväggen påverkas av träning på olika sätt. Enligt olika studier ökar eller minskar a. popliteas lumendiameter av aerob träning. Syftet med denna studie är att se om regelbunden aerob träning påverkar lumendiametern i a. poplitea. Med hjälp av ultraljud hararteria popliteas lumendiameter mätts hos totalt 31 frivilliga personer, där hälften var tränade och resten var otränade, både kvinnor och män. Insamlad data har analyserats med IBM SPSS version 27. Denna studie bekräftar det tidigare studier sagt, att män har större lumendiameter i a. poplitea än kvinnor. Lumendiametern i a. poplitea är större i dess proximala och mediala delar, än i dess distala del. Studien visar inga signifikanta skillnader i a. popliteas lumendiameter mellan personer som tränar regelbundet och otränade personer, det finns tendenser till att de som tränar har större lumendiameter. Det resultatet överensstämmer med några av de tidigare studierna, med tanke på denna studies storlek börstörre och mer omfattande studier behöver göras för säkrare resultat. / The artery in the knee, popliteal artery, can get an aneurysm, usually if the person already hasan aortic aneurysm. Vessels are affected by exercise in different ways. Various studies say that the lumen diameter in a. poplitea both increases and decreases with aerobic exercise. The purpose of this study is to see if regular aerobic exercise affects the diameter of the popliteal artery. Using ultrasound, the lumen diameter of the popliteal artery has been measured in trained and untrained women and men, in total 31 volunteers was examined. The collected data were then analysed with IBM SPSS version 27. This study confirms that men have larger lumen diameters in the popliteal artery than women. The lumen diameter of the popliteal artery is larger in its proximal and medial parts, than in the distal parts. This study has concluded thatthere is no significant difference in the popliteal artery's lumen diameter in trained and in untrained persons, however there is a tendency that trained persons have larger lumen diameters than untrained persons. That is consistent with some of the previous studies, but larger and more comprehensive studies need to be done for more accurate results.

No description available.

No description available.

Bakgrund: Tetrakloretylen (TTCE) har flera humantoxikologiska och ekotoxikologiskaegenskaper, bla ökad risk för flera olika typer av cancer samt bildande av marknära ozon som bidrar till växthuseffekten. Ämnet används ofta som lösningsmedel vid analys av mineraloljor i vatten med hjälp av IR-spektrofotometri. TTCE är svårt att ersätta med andra lösningsmedel på grund av dess positiva egenskaper vid denna typ av analys. Bland annat ger TTCE inget eller ytterst lite utslag på FTIR spektrat där avläsning av alifatiska och aromatiska kolväten sker. Syfte: Syftet med rapporten är att validera ett nytt instrument samt att minimera hälsoriskerna för berörd laboratoriepersonal som arbetar med tetrakloretylen. Metod: I samband med valideringen av metoden, analys av mineraloljor i vatten medinfraröd spektrofotometri, har en riskbedömning i form av en checklista genomförtstillsammans med bland annat skyddsombud för att säkerställa en säker arbetsmiljö. Resultat: Instrumentets och metodens linjäritet klarade kravet på R2>0,995. Totalt extraherbara alifatiska och aromatiska kolväten i halterna 1,0 samt 15 mg/l klarade mätosäkerheten på 15%. Data över riktigheten behöver kompleteras innan ett rättvist resultat kan erhållas. Slutsats: Valideringen av metoden LidMiljö0A.01.19 version 10, mineralolja i vatten med infraröd spektrofotometri, visar att den tidigare rapporteringsgränsen på 1,0 mg/l kommer att kvarstå. Hälsoriskerna för personalen som arbetar med analysmetoden, kan enligt denna studie minimeras till en godtagbar nivå som innebär att laboranten utsätts för minimal risk. / Background: Tetrachlorethylene (TTCE) has several human- and ecotoxicological properties, including increased risk for several types of cancer, as well as formation of ground-level ozone that contributes to the greenhouse effect. The substance is often used as solvent for the analysis of mineral oils in water by means of IR spectrophotometry. TTCE is difficult to replace with other solvents due to its positive properties in this type of analysis. Among other things, TTCE gives no or very little impact on the FTIR spectra where reading of aliphatic and aromatic hydrocarbons occurs. Purpose: The purpose of this report is to validate a new instrument and to minimize the health risks for the laboratory staff using the method. Method: In connection with validation of the method, analysis of mineral oils in water with infrared-spectrophotometry, a risk assessment in the form of a checklist has been implemented together with personnel which has an increased resonsibility of the working enviroment, to ensure a safety of the workplace. Results: The linearity of the instrument and the method met the requirement of R2> 0,995. Total extractable aliphatic and aromatic hydrocarbons at levels of 1,0 and 15 mg/l achieved uncertainty of the measurement by 15%. The data regarding correctness needs to be further expanded to obtain a relaiable result.3 Conclusion: The validation of the method LidMiljö0A.01.19 version 10, mineral oil in water with infrared-spectrophotometry, shows that the previous limit of 1,0 mg/l will remain. Health risks for the personnel involved in the analysis method can, according to this study, be minimized to an acceptable level.

Retiring baby boomers and the lack of interest and awareness among college students to enroll in an accredited Clinical Laboratory Science (CLS) program have created a shortage of CLS professionals in the 21st century. The U.S. Bureau of Labor Statistics predicts 18,000 CLS vacancies by 2018. However, only about 5,000 students graduate from accredited CLS programs each year. The purpose of this study was to explore students' perceptions of allied health professions and factors that influenced students and CLS professionals to select CLS as a profession. Bandura's social cognitive career theory served as the theoretical framework for this phenomenological study. Convenient purposeful sampling was used to select the 7 CLS professionals, 5 high school students, and 5 college students in the Chicago area. Participants took part in either a 30- to 60-minute group session or a 45- to 90-minute semi structured interview. Qualitative analysis included open axial coding to identify emerging patterns and themes from the transcripts. Findings revealed that the perceptions of both high school and college students' knew little about the CLS profession, and factors influencing CLS as a career choice included interests in science, health care, and family. CLS professionals indicated their interests in science and a high demand for CLS services in the workforce led them to pursue careers in the field. Implications for social change include improving professional-development programs for student awareness of allied health professions and mitigating the shortage of clinical laboratory scientists.