Determination of signature volatile odor chemicals emanating from novel biological specimens by non-invasive analytical techniques for the potential use in forensic identifications

Human scent, or the volatile organic compounds (VOCs) produced by an individual, has been recognized as a biometric measurement because of the distinct variations in both the presence and abundance of these VOCs between individuals. In forensic science, human scent has been used as a form of associative evidence by linking a suspect to a scene/object through the use of human scent discriminating canines. The scent most often collected and used with these specially trained canines is from the hands because a majority of the evidence collected is likely to have been handled by the suspect. However, the scents from other biological specimens, especially those that are likely to be present at scenes of violent crimes, have yet to be explored. Hair, fingernails and saliva are examples of these types of specimens. ^ In this work, a headspace solid phase microextraction gas chromatography-mass spectrometry (HS-SPME-GC-MS) technique was used for the identification of VOCs from hand odor, hair, fingernails and saliva. Sixty individuals were sampled and the profiles of the extracted VOCs were evaluated to assess whether they could be used for distinguishing individuals. Preliminary analysis of the biological specimens collected from an individual (intra-subject) showed that, though these materials have some VOCs in common, their overall chemical profile is different for each specimen type. Pair-wise comparisons, using Spearman Rank correlations, were made between the chemical profiles obtained from each subject, per a specimen type. Greater than 98.8% of the collected samples were distinguished from the subjects for all of the specimen types, demonstrating that these specimens can be used for distinguishing individuals. ^ Additionally, field trials were performed to determine the utility of these specimens as scent sources for human scent discriminating canines. Three trials were conducted to evaluate hair, fingernails and saliva in comparison to hand odor, which was considered the standard source of human odor. It was revealed that canines perform similarly to these alternative human scent sources as they do to hand odor implying that, though there are differences in the chemical profiles released by these specimens, they can still be used for the discrimination of individuals by trained canines.^

Photo degradation of contaminants of emerging concern (CECs) under simulated solar radiation: Implications for their environmental fate

Contaminants of emerging concern (CECs) are continuously being released into the environment mainly because of their incomplete removal in the sewage treatment plants (STPs). The CECs selected for the study include antibiotics (macrolides, sulfonamides and ciprofloxacin), sucralose (an artificial sweetener) and dioctyl sulfosuccinate (DOSS, chemical dispersant used in the Deepwater Horizon oil spill). After being discharged into waterways from STPs, photo degradation is a key factor in dictating the environmental fate of antibiotics and sucralose. Photodegradation efficiency depends on many factors such as pH of the matrix, matrix composition, light source and structure of the molecule. These factors exert either synergistic or antagonistic effects in the environment and thus experiments with isolated factors may not yield the same results as the natural environmental processes. Hence in the current study photodegradation of 13 CECs (antibiotics, sucralose and dicotyl sulfosuccinate) were evaluated using natural water matrices with varying composition (deionized water, fresh water and salt water) as well as radiation of different wavelengths (254 nm, 350 nm and simulated solar radiation) in order to mimic natural processes. As expected the contribution of each factor on the overall rate of photodegradation is contaminant specific, for example under similar conditions, the rate in natural waters compared to pure water was enhanced for antibiotics (2-11 fold), significantly reduced for sucralose (no degradation seen in natural waters) and similar in both media for DOSS. In general, it was observed that the studied compounds degraded faster at 254 nm, while when using a simulated sunlight radiation the rate of photolysis of DOSS increased and the rates for antibiotics decreased in comparison to the 350 nm radiation. The photo stability of the studied CECs followed the order sucralose > DOSS > macrolides > sulfonamides > ciprofloxacin and a positive relationship was observed between photo stability and their ubiquitous presence in natural aquatic matrices. An online LC-MS/MS method was developed and validated for sucralose and further applied to reclaimed waters (n =56) and drinking waters (n = 43) from South Florida. Sucralose was detected in reclaimed waters with concentrations reaching up to 18 μg/L. High frequency of detection (> 80%) in drinking waters indicate contamination of ground waters in South Florida by anthropogenic activity.^

Possibilidades de enfoque CTS para o ensino superior de química: proposta de uma abordagem para ácidos e bases

Scientific education has been passing by redefinitions, contestations and new contributions from the research on science teaching. One contribution is the idea of science and technology literacy, allowing the citizens not only knowing science but also understand aspects on the construction and motivation of scientific and technological research. In accordance with this idea, there is the Science-Technology-Society (STS) studies which, since the 1970s, has been contributing for science teaching and learning according to the comprehension of the relationships with society in the Western countries of the North. In Brazil, this approach began to gain projection from the 1990s when the first essays on the theme were published. Currently, there is a clear influence of this approach on the national curriculum guidelines, especially for the area of Natural Sciences, and also on the textbooks chosen by the High School National Program (Programa Nacional do Ensino Médio). However, there seems to be a gap in relation to the discussion on the specific curricular component seen in college on this approach. Thus, this study aims at adopting the approach STS, face to the preparation of complimentary educational material on acid and bases concepts studied in the course of General Chemistry of the Natural Sciences graduation program. To this end, it was performed a bibliographical research aiming at making the state-of-the-art in in these concepts in specific literature to science teaching. It is divided in two stages: systematic study (with sixteen journals chosen according to Qualis-Capes and an unsystematic study with direct search in databases and references in the papers of the systematic study. The studies had their content analyzed and the categories chosen a priori were the level of education, the acid-base theory adopted, and the strategy/theoretical frame of reference adopted. A second stage aimed at identifying attitudes and beliefs on STS (Science-Technology-Society) and CSE (Chemistry-Society-Environment) of students in the teacher and technologist training course in three diferent institutions: UTFPR, UFRN and IFRN. In this study, it was used two questionnaires, composed of a Likert scale, semantic differential scale and open questions. The quantitative data reliability was estimated through Cronbach’s alpha method, and tha data were treated according to classic statistics, using the mean as the centrality measures, and the mean deviation as dispersion. The qualitative data were treated according to the content analysis with categories taken from the reading of answers. In the third stage, it was analyzed the presence of STS and CSE content in chapters on acid and bases concepts of nine General Chemistry textbooks, frequently used in graduation programs in public institutions of the state of Rio Grande do Norte. The results showed that there are few proposals of acid and bases teaching, and they are generally aimed at High School or at instrumentation for teaching courses, and no course for General Chemistry. The student’s attitudes and beliefs show the presence of a positivist point of view based on the concept of Science and Technology neutrality and the salvation of its mediation. The books analysis showed just a few content on STS and CSE are found in the studied chapters, and they are generally presented disjointedly in relation to the rest of the main text. In the end, as suggestion to solve the absence of proposals STS in General Chemistry books, as well as the student’s positivist attitudes, it was developed some educational material to be used in the course of General Chemistry at College. The material is structured to introduce a historical view of the concepts preparation, present the use of materials, the industrial and technological processes, and social and environmental consequences of this activities

Entrepreneurship: a long way to go

Entrepreneurship education has emerged as one popular research domain in academic fields given its aim at enhancing and developing certain entrepreneurial qualities of undergraduates that change their state of behavior, even their entrepreneurial inclination and finally may result in the formation of new businesses as well as new job opportunities. This study attempts to investigate the Colombian student´s entrepreneurial qualities and the influence of entrepreneurial education during their studies.

Simulating short lived carbonaceous compounds with an atmospheric chemistry general circulation model

Ein neu entwickeltes globales Atmosphärenchemie- und Zirkulationsmodell (ECHAM5/MESSy1) wurde verwendet um die Chemie und den Transport von Ozonvorläufersubstanzen zu untersuchen, mit dem Schwerpunkt auf Nichtmethankohlenwasserstoffen. Zu diesem Zweck wurde das Modell durch den Vergleich der Ergebnisse mit Messungen verschiedenen Ursprungs umfangreich evaluiert. Die Analyse zeigt, daß das Modell die Verteilung von Ozon realistisch vorhersagt, und zwar sowohl die Menge als auch den Jahresgang. An der Tropopause gibt das Modell den Austausch zwischen Stratosphäre und Troposphäre ohne vorgeschriebene Flüsse oder Konzentrationen richtig wieder. Das Modell simuliert die Ozonvorläufersubstanzen mit verschiedener Qualität im Vergleich zu den Messungen. Obwohl die Alkane vom Modell gut wiedergeben werden, ergibt sich einige Abweichungen für die Alkene. Von den oxidierten Substanzen wird Formaldehyd (HCHO) richtig wiedergegeben, während die Korrelationen zwischen Beobachtungen und Modellergebnissen für Methanol (CH3OH) und Aceton (CH3COCH3) weitaus schlechter ausfallen. Um die Qualität des Modells im Bezug auf oxidierte Substanzen zu verbessern, wurden einige Sensitivitätsstudien durchgeführt. Diese Substanzen werden durch Emissionen/Deposition von/in den Ozean beeinflußt, und die Kenntnis über den Gasaustausch mit dem Ozean ist mit großen Unsicherheiten behaftet. Um die Ergebnisse des Modells ECHAM5/MESSy1 zu verbessern wurde das neue Submodell AIRSEA entwickelt und in die MESSy-Struktur integriert. Dieses Submodell berücksichtigt den Gasaustausch zwischen Ozean und Atmosphäre einschließlich der oxidierten Substanzen. AIRSEA, welches Informationen über die Flüssigphasenkonzentration des Gases im Oberflächenwasser des Ozeans benötigt wurde ausgiebig getestet. Die Anwendung des neuen Submodells verbessert geringfügig die Modellergebnisse für Aceton und Methanol, obwohl die Verwendung einer vorgeschriebenen Flüssigphasenkonzentration stark den Erfolg der Methode einschränkt, da Meßergebnisse nicht in ausreichendem Maße zu Verfügung stehen. Diese Arbeit vermittelt neue Einsichten über organische Substanzen. Sie stellt die Wichtigkeit der Kopplung zwischen Ozean und Atmosphäre für die Budgets vieler Gase heraus.

The Philosophical magazine : or Annals of chemistry, mathematics, astronomy, natural history and general science.

2nd ser. : v.9 (1831)

The Philosophical magazine : or Annals of chemistry, mathematics, astronomy, natural history and general science.

2nd ser. : v.3 (1828)

The Philosophical magazine : or Annals of chemistry, mathematics, astronomy, natural history and general science.

2nd ser. : v.4 (1828)

Success of referral for alcohol dependent patients from a general hospital: predictive value of patient and process characteristics.

To assess the effectiveness of a multidisciplinary evaluation and referral process in a prospective cohort of general hospital patients with alcohol dependence. Alcohol-dependent patients were identified in the wards of the general hospital and its primary care center. They were evaluated and then referred to treatment by a multidisciplinary team; those patients who accepted to participate in this cohort study were consecutively included and followed for 6 months. Not included patients were lost for follow-up, whereas all included patients were assessed at time of inclusion, 2 and 6 months later by a research psychologist in order to collect standardized baseline patients' characteristics, process salient features and patients outcomes (defined as treatment adherence and abstinence). Multidisciplinary evaluation and therapeutic referral was feasible and effective, with a success rate of 43%for treatment adherence and 28%for abstinence at 6 months. Among patients' characteristics, predictors of success were an age over 45, not living alone, being employed and being motivated to treatment (RAATE-A score < 18), whereas successful process characteristics included detoxification of the patient at time of referral and a full multidisciplinary referral meeting. This multidisciplinary model of evaluation and referral of alcohol dependent patients of a general hospital had a satisfactory level of effectiveness. Predictors of success and failure allow to identify subsets of patients for whom new strategies of motivation and treatment referral should be designed.

Success of a general school-based physical activity intervention on bone mineral content depends on pubertal stage but not on gender

Aims: We performed a randomised controlled trial in children of both gender and different pubertal stages to determine whether a school-based physical activity (PA) program during a full schoolyear influences bone mineral content (BMC) and whether there are differences in response for boys and girls before and during puberty. Methods: Twenty-eight 1st and 5th grade classes were cluster randomised to an intervention (INT, 16 classes, n=297) and control (CON; 12 classes, n=205) group. The intervention consisted of a multi-component PA intervention including daily physical education during a full school year. Each lesson was predetermined, included about ten minutes of jumping or strength training exercises of various intensity and was the same for all children. Measurements included anthropometry (height and weight), tanner stages (by self-assessment), PA (by accelerometry) and BMC for total body, femoral neck, total hip and lumbar spine using dualenergy X-ray absorptiometry (DXA). Bone parameters were normalized for gender and tanner stage (pre- vs. puberty). Analyses were performed by a regression model adjusted for gender, baseline height, baseline weight, baseline PA, post-intervention tanner stage, baseline BMC, and cluster. Researchers were blinded to group allocation. Children in the control group did not know about the intervention arm. Results: 217 (57%) of 380 children who initially agreed to have DXA measurements had also post-intervention DXA and PA data. Mean age of prepubertal and pubertal children at baseline was 9.0±2.1 and 11.2±0.6 years, respectively. 47/114 girls and 68/103 boys were prepubertal at the end of the intervention. Compared to CON, children in INT showed statistically significant increases in BMC of total body (adjusted z-score differences: 0.123; 95%>CI 0.035 to 0.212), femoral neck (0.155; 95%>CI 0.007 to 0.302), and lumbar spine (0.127; 95%>CI 0.026 to 0.228). Importantly, there was no gender*group, but a tanner*group interaction consistently favoring prepubertal children. Conclusions: Our findings show that a general, but stringent school-based PA intervention can improve BMC in elementary school children. Pubertal stage, but not gender seems to determine bone sensitivity to physical activity loading.

Success of referral for alcohol dependent patients from a general hospital : predictive value of patient and process characteristics

RESUME: Introduction L'objectif de cette étude prospective de cohorte était d'estimer l'efficacité d'un processus de prise en charge standardisé de patients dépendants de l'alcool dans le contexte d'un hôpital universitaire de soins généraux. Ce modèle de prise en charge comprenait une évaluation multidisciplinaire puis des propositions de traitements individualisées et spécifiques (« projet thérapeutique »). Patients et méthode 165 patients alcoolo-dépendants furent recrutés dans différents services de l'hôpital universitaire, y compris la policlinique de médecine. Ils furent dans un premier temps évalués par une équipe multidisciplinaire (médecin interniste, psychiatre, assistant social), puis un projet thérapeutique spécialisé et individualisé leur fut proposé lors d'une rencontre réunissant le patient et l'équipe. Tous les patients éligibles acceptant de participer à l'étude (n=68) furent interrogés au moment de l'inclusion puis 2 et 6 mois plus tard par une psychologue. Des informations standardisées furent recueillies sur les caractéristiques des patients, le processus de prise en charge et l'évolution à 6 mois. Les critères de succès utilisés à 6 mois furent: l'adhérence au traitement proposé et l'abstinence d'alcool. Résultats Lors de l'évaluation à 6 mois, 43% des patients étaient toujours en traitement et 28% étaient abstinents. Les variables prédictrices de succès parmi les caractéristiques des patients étaient un âge de plus de 45 ans, ne pas vivre seul, avoir un travail et être motivé pour un traitement (RAATE-A <18). Pour les variables dépendantes du processus de prise en charge, un sevrage complet de l'alcool lors de la rencontre multidisciplinaire ainsi que la présence de tous les membres de l'équipe à cette réunion étaient des facteurs associés au succès. Conclusion L'efficacité de ce modèle d'intervention pour patients dépendants de l'alcool en hôpital de soins généraux s'est montrée satisfaisante, en particulier pour le critère de succès adhérence au traitement. Des variables associées au succès ou à l'échec à 6 mois ont pu être mises en évidence, permettant d'identifier des populations de patients évoluant différemment. Des stratégies de prise en charge tenant compte de ces éléments pourraient donc être développées, permettant de proposer des traitements plus adaptés ainsi qu'une meilleure rétention des patients alcooliques dans les programmes thérapeutiques. ABSTRACT. To assess the effectiveness of a multidisciplinary evaluation and referral process in a prospective cohort of general hospital patients with alcohol dependence, alcohol-dependent patients were identified in the wards of the general hospital and its primary care center. They were evaluated and then referred to treatment by a multidisciplinary team; those patients who accepted to participate in this cohort study were consecutively included and followed for 6 months. Not included patients were lost for follow-up, whereas all included patients were assessed at time of inclusion, 2 and 6 months later by a research psychologist in order to collect standardized baseline patients' characteristics, process salient features and patients outcomes (defined as treatment adherence and abstinence). Multidisciplinary evaluation and therapeutic referral was feasible and effective, with a success rate of 43% for treatment adherence and 28% for abstinence at 6 months. Among patients' characteristics, predictors of success were an age over 45, not living alone, being employed and being motivated to treatment (RAATE-A score < 18), whereas successful process characteristics included detoxification of the patient at time of referral and a full multidisciplinary referral meeting. This multidisciplinary model of evaluation and referral of alcohol dependent patients of a general hospital had a satisfactory level of effectiveness. Predictors of success and failure allow the identification of subsets of patients for whom new strategies of motivation and treatment referral should be designed.

How Learning Styles, Chemistry Attitudes and Experiences, Confidence, and Demographics Correlate with Academic Success in First and Second Year Chemistry Courses

At Brock University, the Faculty of Mathematics and Science currently has one of the highest percentages of students on academic probation, with many students reporting the most difficulty with Introductory Chemistry in first year and Organic Chemistry in second year. To identify strategies to improve students' performance and reduce the number of students on academic probation, a multi-year research project was undertaken involving several chemistry courses. Students were asked to complete three questionnaires, and provide consent to obtain their final Chemistry grade from the Registrar's Office. Research began at the end of the 2007-08 academic year with CHEM IPOO, and in the 2008-09 academic year, students in the larger CHEM IF92 Introductory Chemistry course were invited to participate in this research near the beginning of the academic year. Students who went on to take second year Organic and Analytical Chemistry were asked to complete these questionnaires in each second year course. The three questionnaires included the Kolb Learning Styles Inventory (Kolb, 1984) modified to include specific reference to Chemistry in each question, Dalgety, ColI, and Jones' (2002) Chemistry Attitudes and Experiences Questionnaire (CAEQ), and lastly, a demographic survey. Correlations were found between learning style and academic success; concrete learners were not as successful as abstract learners. Differences were noted between females and males with respect to learning styles, academic success, and confidence. Several differences were also noted between those who are the First in the Family to attend university and those who are not First in the Family to attend university.

Example General Feedback on Routes to Success Portfolios

This document provides example feedback which has been generated following the marking of a class set of portfolios. It is used as a part of the Routes to Success Module, specifically on the section titled Sustaining Success. Students can read the feedback prior to completing the portfolio to alert them to the possible shortfalls which may occur when they undertake this type of task. The feedback is introduced in the context that the task of completing the portfolio is a developmental one, and that students can expect to learn and improve their performance for this type of task as they develop and refine their skills.