The Delicate Balance to Adjustment: A Qualitative Approach of Student's Transition to the First Year at University.

First year experience in higher education has been extensively investigated in the literature. Yet, two limitations can be identified out of the literature. The majority of the studies focused on single factor analysis, restraining the multifactorial understanding of adjustment's determinants. Moreover, the temporal unfolding of the first year at the university has mainly been disregarded, limiting the dynamic framing of adjustment process. To overcome these limitations, the current study used a longitudinal qualitative design in order to grasp the dynamic complexity of adjustment process. Semi-structured interviews were conducted in two steps with 17 freshmen from Science department. The aims were to unfold the constructs at play in student's adjustment process and the dynamic interplay between them over time. The analyses were grounded into Nicholson's theoretical framework of transition cycle and the material was analyzed through thematic and sequential analysis. Four themes (readiness, reaching personal drives, fighting an overwhelming program and becoming a self-regulated learner) and four different events (starting up, click, exhaustion and deficiencies accumulation) were identified in the material disclosing the dynamic nature of adjustment process. An overall reflection on the findings is proposed in the conclusion.

Great interspecies and intraspecies diversity of dairy propionibacteria in the production of cheese aroma compounds.

Flavor is an important sensory property of fermented food products, including cheese, and largely results from the production of aroma compounds by microorganisms. Propionibacterium freudenreichii is the most widely used species of dairy propionibacteria; it has been implicated in the production of a wide variety of aroma compounds through multiple metabolic pathways and is associated with the flavor of Swiss cheese. However, the ability of other dairy propionibacteria to produce aroma compounds has not been characterized. This study sought to elucidate the effect of interspecies and intraspecies diversity of dairy propionibacteria on the production of aroma compounds in a cheese context. A total of 76 strains of Propionibacterium freudenreichii, Propionibacterium jensenii, Propionibacterium thoenii, and Propionibacterium acidipropionici were grown for 15 days in pure culture in a rich medium derived from cheese curd. In addition, one strain each of two phylogenetically related non-dairy propionibacteria, Propionibacterium cyclohexanicum and Propionibacterium microaerophilum were included. Aroma compounds were analyzed using headspace trap-gas chromatography-mass spectrometry (GC-MS). An analysis of variance performed on GC-MS data showed that the abundance of 36 out of the 45 aroma compounds detected showed significant differences between the cultures. A principal component analysis (PCA) was performed for these 36 compounds. The first two axes of the PCA, accounting for 60% of the variability between cultures, separated P. freudenreichii strains from P. acidipropionici strains and also differentiated P. freudenreichii strains from each other. P. freudenreichii strains were associated with greater concentrations of a variety of compounds, including free fatty acids from lipolysis, ethyl esters derived from these acids, and branched-chain acids and alcohols from amino acid catabolism. P. acidipropionici strains produced less of these compounds but more sulfur-containing compounds from methionine catabolism. Meanwhile, branched-chain aldehydes and benzaldehyde were positively associated with certain strains of P. jensenii and P. thoenii. Moreover, the production of compounds with a common origin was correlated. Compound abundance varied significantly by strain, with fold changes between strains of the same species as high as in the order of 500 for a single compound. This suggests that the diversity of dairy propionibacteria can be exploited to modulate the flavor of mild cheeses.

[Screening for melanoma, an advanced practice nurse consultation]. / Dépistage du mélanome, pratique collaborative d'une infirmière experte.

In the dermatology consultation, at Cochin hospital, Paris, a nurse cooperates with a dermatologist in order to insure the clinical follow-up for high-risk melanoma patients. To adopt this innovative public health approach, the nurse has received theoretical, clinical and educational knowledge.

Survival and metabolic activity of selected strains of Propionibacterium freudenreichii in the gastrointestinal tract of human microbiota-associated rats.

In addition to their use in cheese technology, dairy propionibacteria have been identified as potential probiotics. However, to have a probiotic effect, propionibacteria have to survive and to remain metabolically active in the digestive tract. The aim of the present study was to investigate the survival and metabolic activity of Propionibacterium freudenreichii within the gastrointestinal tract of human microbiota-associated rats, and its influence on intestinal microbiota composition and metabolism. Twenty-five dairy Propionibacterium strains were screened for their tolerance towards digestive stresses and their ability to produce propionate in a medium mimicking the content of the human colon. Three strains were selected and a daily dose of 2 x 10(10) colony-forming units was fed to groups of human microbiota-associated rats for 20 d before microbiological, biochemical and molecular investigations being carried out. These strains all reached 8-log values per g faeces, showing their ability to survive in the gastrointestinal tract. Transcriptional activity within the intestine was demonstrated by the presence of P. freudenreichii-specific transcarboxylase mRNA. The probiotic efficacy of propionibacteria was yet species- and strain-dependent. Indeed, two of the strains, namely TL133 and TL1348, altered the faecal microbiota composition, TL133 also increasing the caecal concentration of acetate, propionate and butyrate, while the third strain, TL3, did not have similar effects. Such alterations may have an impact on gut health and will thus be taken into consideration for further in vivo investigations on probiotic potentialities of P. freudenreichii.