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1.
Anal Chem ; 87(9): 4597-600, 2015 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-25901421

RESUMO

Elemental analysis of materials is fundamentally important to science and technology. Many elemental analysis methods have been developed, but three-dimensional nondestructive elemental analysis of bulk materials has remained elusive. Recently, our project team, dreamX (damageless and regioselective elemental analysis with muonic X-rays), developed a nondestructive depth-profiling elemental analysis method after a decade of research. This new method utilizes a new type of probe; a negative muon particle and high-energy muonic X-rays emitted after the muon stops in a material. We performed elemental depth profiling on an old Japanese gold coin (Tempo-Koban) using a low-momentum negative muon beam and successfully determined that the Au concentration in the coin gradually decreased with depth over a micrometer length scale. We believe that this method will be a promising tool for the elemental analysis of valuable samples, such as archeological artifacts.

2.
Sci Rep ; 14(1): 1797, 2024 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-38245588

RESUMO

The amount of C in steel, which is critical in determining its properties, is strongly influenced by steel production technology. We propose a novel method of quantifying the bulk C content in steel non-destructively using muons. This revolutionary method may be used not only in the quality control of steel in production, but also in analyzing precious steel archaeological artifacts. A negatively charged muon forms an atomic system owing to its negative charge, and is finally absorbed into the nucleus or decays to an electron. The lifetimes of muons differ significantly, depending on whether they are trapped by Fe or C atoms, and identifying the elemental content at the muon stoppage position is possible via muon lifetime measurements. The relationship between the muon capture probabilities of C/Fe and the elemental content of C exhibits a good linearity, and the C content in the steel may be quantitatively determined via muon lifetime measurements. Furthermore, by controlling the incident energies of the muons, they may be stopped in each layer of a stacked sample consisting of three types of steel plates with thicknesses of 0.5 mm, and we successfully determined the C contents in the range 0.20-1.03 wt% depth-selectively, without sample destruction.

3.
GMS J Med Educ ; 40(3): Doc27, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37377572

RESUMO

Objective: Climate change constitutes a major challenge. The higher education sector plays an important role in regard to climate change and the adaptation to its consequences. Various approaches toward the integration of environmental subject areas to higher education teaching have already been described in other studies, but there is a lack of data supporting the effectiveness of these approaches in changing not only the environmental knowledge of students, but also their awareness. To address this, the present study tracked whether student attitudes about the environment could be changed by implicitly addressing medically relevant environmental topics as part of an online seminar. Methods: Second semester students of molecular medicine attending a mandatory 14-hour online seminar, which was required to obtain additive key qualifications and which consisted of independent study phases as well as online class meetings, were divided into two groups: the intervention group (IG, n=27, thereof 20 in the pretest and 21 in the posttest) was exposed to medically relevant environmental topics, while the comparison group (CG, n=26, thereof 22 in the pretest and 21 in the posttest) was exposed to general, non-environmental medical topics. Surveys were conducted with standardized questionnaires before and after the seminar in order to study the influence on the students' environmental knowledge, awareness and other personal attitudes. Results: While the seminar did not significantly change the environmental awareness in either group, the environmental knowledge of the IG was significantly increased by the group's exposure to environmental topics. In addition, the IG assessed its own environmental awareness regarding sustainable working methods in a laboratory as significantly higher after the seminar than the CG did, and some students of the IG had become more interested in issues relating to sustainability. Conclusion: The approach used to communicate environmental content mainly increased the environmental knowledge of students and piqued the interest of some students in climate-related and environmental topics. However, it was not possible to change deeper personal attitudes about environmental awareness, especially everyday behavior.


Assuntos
Educação Médica , Estudantes de Medicina , Estudantes de Enfermagem , Humanos , Currículo , Atitude , Inquéritos e Questionários
4.
Sci Adv ; 9(43): eadg6874, 2023 10 27.
Artigo em Inglês | MEDLINE | ID: mdl-37878703

RESUMO

Interleukins are secreted proteins that regulate immune responses. Among these, the interleukin 12 (IL-12) family holds a central position in inflammatory and infectious diseases. Each family member consists of an α and a ß subunit that together form a composite cytokine. Within the IL-12 family, IL-35 remains particularly ill-characterized on a molecular level despite its key role in autoimmune diseases and cancer. Here we show that both IL-35 subunits, IL-12α and EBI3, mutually promote their secretion from cells but are not necessarily secreted as a heterodimer. Our data demonstrate that IL-12α and EBI3 are stable proteins in isolation that act as anti-inflammatory molecules. Both reduce secretion of proinflammatory cytokines and induce the development of regulatory T cells. Together, our study reveals IL-12α and EBI3, the subunits of IL-35, to be functionally active anti-inflammatory immune molecules on their own. This extends our understanding of the human cytokine repertoire as a basis for immunotherapeutic approaches.


Assuntos
Interleucina-12 , Interleucinas , Humanos , Citocinas/metabolismo , Interleucina-12/metabolismo , Interleucinas/metabolismo , Antígenos de Histocompatibilidade Menor/metabolismo , Linfócitos T Reguladores
5.
Biochem Mol Biol Educ ; 50(5): 483-493, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35841313

RESUMO

On-site teaching at Ulm University was restricted in the summer semester (SS) 2020 due to the Corona pandemic. The biochemistry seminar "From gene to protein" in the 2nd preclinical semester, which had been successfully conducted as an Inverted Classroom (IC), had to be changed to an online concept. The aim of this study was to analyze the concept conversion in terms of students' satisfaction and knowledge acquisition. In the seminar, human medical students of the 2nd semester acquired biochemical and competency-oriented learning content. In SS2019, the course was taught using the IC concept. For the conversion to the online format in the SS2020, alternative teaching materials were developed and used. Students' satisfaction was assessed by an evaluation questionnaire and knowledge acquisition was tested by a written biochemistry exam. For both teaching concepts a high level of satisfaction was detected. Individual evaluation criteria were evaluated similarly by the students for both concepts. The online concept led up to significantly higher biochemistry exam scores. Due to the high levels of students' satisfaction in both concepts and the results of the biochemistry exam, it can be concluded that online teaching offers a suitable substitute. Based on these results, it is worth to undertake further research on digitization of studies.


Assuntos
Currículo , Estudantes de Medicina , Bioquímica/educação , Humanos , Aprendizagem , Satisfação Pessoal
6.
Z Evid Fortbild Qual Gesundhwes ; 174: 97-102, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36064704

RESUMO

INTRODUCTION: Global warming is one of the major challenges faced by society. To raise students' awareness related to these issues, we embedded environmental learning goals in mandatory courses. The aim of this initiative was to determine whether the integration of environmental topics into a seminar focussing on non-environmental issues facilitates changes in the environmental knowledge and awareness of students. METHODS: Third-year molecular medicine students (intervention group, IG) were assigned short environment-related tasks in a not environment-related scientific writing seminar. Using standardized questionnaires before and after the seminar, students were assessed with a set of up to 48 questions relating to environmental affect, cognition, behavioral intention and knowledge as well as specific personal aspects. The comparison group (CG) consisted of third-year dentistry students who were assessed twice during an equivalent pre-post time period and who did not attend the seminar. The analysis was carried out with 15 students from the IG and 14 from the CG. RESULTS: Integrating environmental topics into a scientific writing seminar focussing on non-environmental issues led to a significantly increased level of awareness of the threats from climate change in the IG (p<0.05). No further significant changes in other areas of environmental awareness were observed in either group. In addition, the environmental knowledge of the IG students (p≤0.01) but not of the CG students (p=0.285) was significantly enhanced. DISCUSSION AND CONCLUSION: This study shows that factual environmental knowledge on the issues addressed can be increased by a cautious approach of environmental communication. However, more deep-seated personal attitudes and environmental awareness cannot be sustainably changed using this low intervention dose.


Assuntos
Educação Médica , Estudantes de Medicina , Humanos , Alemanha , Inquéritos e Questionários , Currículo
7.
Dev Cell ; 57(24): 2714-2730.e8, 2022 12 19.
Artigo em Inglês | MEDLINE | ID: mdl-36538894

RESUMO

Cancer stem cells (CSCs) may serve as the cellular seeds of tumor recurrence and metastasis, and they can be generated via epithelial-mesenchymal transitions (EMTs). Isolating pure populations of CSCs is difficult because EMT programs generate multiple alternative cell states, and phenotypic plasticity permits frequent interconversions between these states. Here, we used cell-surface expression of integrin ß4 (ITGB4) to isolate highly enriched populations of human breast CSCs, and we identified the gene regulatory network operating in ITGB4+ CSCs. Specifically, we identified ΔNp63 and p73, the latter of which transactivates ΔNp63, as centrally important transcriptional regulators of quasi-mesenchymal CSCs that reside in an intermediate EMT state. We found that the transcriptional program controlled by ΔNp63 in CSCs is largely distinct from the one that it orchestrates in normal basal mammary stem cells and, instead, it more closely resembles a regenerative epithelial stem cell response to wounding. Moreover, quasi-mesenchymal CSCs repurpose this program to drive metastatic colonization via autocrine EGFR signaling.


Assuntos
Células-Tronco Mesenquimais , Neoplasias , Humanos , Linhagem Celular Tumoral , Células-Tronco Neoplásicas/metabolismo , Transdução de Sinais , Transição Epitelial-Mesenquimal , Neoplasias/patologia
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