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We report the effects of electrolytes on bubble coalescence in nonaqueous solvents methanol, formamide, propylene carbonate, and dimethylsulfoxide (DMSO). Results in these solvents are compared to the ion-specific bubble coalescence inhibition observed in aqueous electrolyte solutions, which is predicted by simple, empirical ion combining rules. Coalescence inhibition by electrolytes is observed in all solvents, at a lower concentration range (0.01 M to 0.1M) to that observed in water. Formamide shows ion-specific salt effects dependent upon ion combinations in a way analogous to the combining rules observed in water. Bubble coalescence in propylene carbonate is also consistent with ion-combining rules, but the ion assignments differ to those for water. In both methanol and DMSO all salts used are found to inhibit bubble coalescence. Our results show that electrolytes influence bubble coalescence in a rich and complex way, but with notable similarities across all solvents tested. Coalescence is influenced by the drainage of fluid between two bubbles to form a film and then the rupture of the film and one might expect that these processes will vary dramatically between solvents. The similarities in behavior we observe show that coalescence inhibition is unlikely to be related to the surface forces present but is perhaps related to the dynamic thinning and rupture of the liquid film through the hydrodynamic boundary condition.

We report the effects of electrolytes on bubble coalescence in nonaqueous solvents methanol, formamide, propylene carbonate, and dimethylsulfoxide (DMSO). Results in these solvents are compared to the ion-specific bubble coalescence inhibition observed in aqueous electrolyte solutions, which is predicted by simple, empirical ion combining rules. Coalescence inhibition by electrolytes is observed in all solvents, at a lower concentration range (0.01 M to 0.1M) to that observed in water. Formamide shows ion-specific salt effects dependent upon ion combinations in a way analogous to the combining rules observed in water. Bubble coalescence in propylene carbonate is also consistent with ion-combining rules, but the ion assignments differ to those for water. In both methanol and DMSO all salts used are found to inhibit bubble coalescence. Our results show that electrolytes influence bubble coalescence in a rich and complex way, but with notable similarities across all solvents tested. Coalescence is influenced by the drainage of fluid between two bubbles to form a film and then the rupture of the film and one might expect that these processes will vary dramatically between solvents. The similarities in behavior we observe show that coalescence inhibition is unlikely to be related to the surface forces present but is perhaps related to the dynamic thinning and rupture of the liquid film through the hydrodynamic boundary condition.

Mennesker som har mistet nærtstående, eller som står i fare for at miste deres liv på grund af sygdom, har ofte en mangfoldighed af forestillinger om livets forhold til døden. Det fænomen at der er flere variationer af liv i døden, er omdrejningspunktet for denne artikel. Som henholdsvis antropolog og teolog [i] er vi særligt optagede af hvordan mennesker erfarer og formulerer flere former for transcendens, dvs. overskridende forhold mellem 'denne verden' og 'den anden verden', i et samfund præget af især kristen kosmologi, vestlig videnskab, men også en hel række andre kosmologier. Forestillinger om liv i og efter døden vil vi se som udtryk for erfaringer af menneskelig forbundethed og adskillelse i forhold til medmennesker og verden og ad den vej forsøge at eksplicitere den polydoksi, dvs. de mangeartede former for tro, som kommer til udtryk.

1: Textes reunis par Danouta Liberski. - 1989. - XIII,161 S. : Ill., graph. Darst., Lit.Hinw., Lit. - (... ; Cahier 9).; 2: Textes reunis par Christine Henry ... - 1991. - 213 S. : Ill., graph. Darst., Lit.Hinw., Lit. - (... ; Cahier 11).; 3: Textes reunis par Danouta Liberski. - 1994. - 237 S. : Ill., graph. Darst., Lit.Hinw., Lit. - (... ; Cahier 13)

Fungal cell wall mannans are complex carbohydrate polysaccharides with different structures in yeasts and molds. In contrast to yeasts, their biosynthetic pathway has been poorly investigated in filamentous fungi. In Aspergillus fumigatus, the major mannan structure is a galactomannan that is cross-linked to the β-1,3-glucan-chitin cell wall core. This polymer is composed of a linear mannan with a repeating unit composed of four α1,6-linked and α1,2-linked mannoses with side chains of galactofuran. Despite its use as a biomarker to diagnose invasive aspergillosis, its biosynthesis and biological function were unknown. Here, we have investigated the function of three members of the Ktr (also named Kre2/Mnt1) family (Ktr1, Ktr4, and Ktr7) in A. fumigatus and show that two of them are required for the biosynthesis of galactomannan. In particular, we describe a newly discovered form of α-1,2-mannosyltransferase activity encoded by the KTR4 gene. Biochemical analyses showed that deletion of the KTR4 gene or the KTR7 gene leads to the absence of cell wall galactomannan. In comparison to parental strains, the Δktr4 and Δktr7 mutants showed a severe growth phenotype with defects in polarized growth and in conidiation, marked alteration of the conidial viability, and reduced virulence in a mouse model of invasive aspergillosis. In yeast, the KTR proteins are involved in protein 0- and N-glycosylation. This study provided another confirmation that orthologous genes can code for proteins that have very different biological functions in yeasts and filamentous fungi. Moreover, in A. fumigatus, cell wall mannans are as important structurally as β-glucans and chitin.IMPORTANCE The fungal cell wall is a complex and dynamic entity essential for the development of fungi. It allows fungal pathogens to survive environmental challenge posed by nutrient stress and host defenses, and it also is central to polarized growth. The cell wall is mainly composed of polysaccharides organized in a three-dimensional network. Aspergillus fumigatus produces a cell wall galactomannan whose biosynthetic pathway and biological functions remain poorly defined. Here, we described two new mannosyltransferases essential to the synthesis of the cell wall galactomannan. Their absence leads to a growth defect with misregulation of polarization and altered conidiation, with conidia which are bigger and more permeable than the conidia of the parental strain. This study showed that in spite of its low concentration in the cell wall, this polysaccharide is absolutely required for cell wall stability, for apical growth, and for the full virulence of A. fumigatus. ; This research was funded by l'Agence Nationale pour la Recherche (AfuInf ANR-16-CE92-0039), la Fondation pour la Recherche Médicale (DEQ20150331722 LATGE Equipe FRM 2015), the French Government's Investissement d'Avenir program, and Laboratoire d'Excellence "Integrative Biology of Emerging Infectious Diseases" (grant ANR-10-LABX-62-IBEID). ; Sí

The food production system throughout the European Union, which includes farm production, harvesting, transport, processing, storage, marketing and consumption, is vast, complex and open. The high volume of trade in fresh vegetables and fruits contributes to the vulnerability to contamination, whether by accident or intent. Outbreak investigation is critical to understanding the sources of contamination and the steps required to minimize it. The fact that much of the trade in these commodities is international makes it critical that mediation efforts and cooperative research cross national barriers, just as the pathogens do. Enhancing the biosecurity of food production requires assessment of the following: how is the food production system currently organized, in what ways might it be vulnerable to contamination, either accidental or deliberate, what are the primary factors that would allow discrimination between deliberate vs. accidental outbreaks, how can the epidemiological and surveillance systems in Europe be strengthened to shorten outbreak response and mediation times, how can implicated fresh produce be traced to its source, and what forensically valid subtyping method(s) is/are available for detection and discrimination of associated foodborne pathogens.

The food production system throughout the European Union, which includes farm production, harvesting, transport, processing, storage, marketing and consumption, is vast, complex and open. The high volume of trade in fresh vegetables and fruits contributes to the vulnerability to contamination, whether by accident or intent. Outbreak investigation is critical to understanding the sources of contamination and the steps required to minimize it. The fact that much of the trade in these commodities is international makes it critical that mediation efforts and cooperative research cross national barriers, just as the pathogens do. Enhancing the biosecurity of food production requires assessment of the following: how is the food production system currently organized, in what ways might it be vulnerable to contamination, either accidental or deliberate, what are the primary factors that would allow discrimination between deliberate vs. accidental outbreaks, how can the epidemiological and surveillance systems in Europe be strengthened to shorten outbreak response and mediation times, how can implicated fresh produce be traced to its source, and what forensically valid subtyping method(s) is/are available for detection and discrimination of associated foodborne pathogens.