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The standardised approach of producing fashion products in conjunction with the fast fashion trend has triggered a throwaway culture where premature disposal of well- functioning fashion products is a major problem. However, a shift has been revealed with the emerging demand for personalised fashion, as opposed to standardised garments. Generation Z is known for its urge to showcase personal identity, which makes this consumer group a driver in the growing trend of customisation. The relevance of customisation in fashion is further fuelled by its capability to enhance consumers’ emotional attachment towards the customised product, which often results in the product being kept longer. The perceived consumer value of customisation is acquired from the final product as well as the co-design process. The purpose of this study is to investigate Generation Z’s perceived value of customised fashion products and the co-design process. The underlying objective is to explore if the concept of customisation has the potential of becoming more established in the future fashion industry. The study follows an abductive reasoning and adopts a mixed method research with the explanatory sequential design. This mixed method design is a two-phase approach starting with the collection and analysis of quantitative data, followed by the compiling and analysis of qualitative data. For the first phase, a self-administered online questionnaire was conducted. The second phase entailed semi-structured interviews, which were designed to make up for obscure results in the survey. The Consumer Perceived Value Tool (CPVT) served as a theoretical lens for analysis and guided the construction of the data collection tools. By means of the CPVT the study found that Generation Z particularly perceive value in the utilitarian and creative-achievement benefits of customised fashion. Moreover, the perceived self-expressiveness and hedonic value were deemed significant to the generation. Generation Z showed little evidence of perceiving value in the uniqueness benefit of customised fashion. Lastly, an additional perceived value of customisation was proposed and is related to environmental sustainability, which is acquired from the benefit of acting more responsibly.

L'urétérolithiase est la cause plus fréquente des douleurs aiguës du flanc de la colique par une obstruction urétérale. En raison d'une douleur irréductible, une intervention d'urgence est souvent nécessaire. 104 patients traités entre le 01/2015 et le 11/2017 en raison d'une urétérolithiase obstructive ont été appariés en ce qui concerne la taille et la localisation des calculs et ont été assignés au groupe eSWL (n= 52) ou au groupe sSWL (n= 52). Entre les deux groupes, il n'y a pas eu de différence statistiquement significative entre le taux d'absence de pierres et le taux de complications. Pour les patients du groupe sSWL, les réinterventions ont été plus souvent abordées. En ce qui concerne le taux d'absence de calculs pour les calculs entre 6 et 9 mm, l'eSWL était significativement supérieure à la sSWL. L'eSWL semble être une procédure d'urgence efficace et sûre par rapport à la sSWL.

In a biological membrane, proteins require specific lipids of distinctive length and chain saturation surrounding them. The active tuning of the membrane thickness therefore opens new possibilities in the study and manipulation of membrane proteins. Here, we introduce the concept of stapling phospholipids to different degrees of interdigitation depth by mixing 1,3-diamidophospholipids with single-chain bolalipids. The mixed membranes were studied by calorimetric assays, electron microscopy, X-ray, and infrared measurements to provide a complete biophysical characterization of membrane stapling. The matching between the diamidophospholipids and the bolalipids can be so strong as to completely induce a new phase that is more stable than the gel phase of the individual components.

Cellular delivery of DNA vectors for the expression of therapeutic proteins is a promising approach to treat monogenic disorders or cancer. Significant efforts in a preclinical and clinical setting have been made to develop potent nonviral gene delivery systems based on lipoplexes composed of permanently cationic lipids. However, transfection efficiency and tolerability of such systems are in most cases not satisfactory. Here, we present a one-pot combinatorial method based on double- reductive amination for the synthesis of short-chain aminolipids. These lipids can be used to maximize the DNA vector delivery when combined with the cationic lipid 1,2- dioleoyl-3-trimethylammonium propane (DOTAP). We incorporated various aminolipids into such lipoplexes to complex minicircle DNA and screened these systems in a human liver-derived cell line (HuH7) for gene expression and cytotoxicity. The lead aminolipid AL-A12 showed twofold enhanced gene delivery and reduced toxicity compared to the native DOTAP:cholesterol lipoplexes. Moreover, AL-A12- containing lipoplexes enabled enhanced transgene expression in vivo in the zebrafish embryo model.

Decisions about admission to selective schools usually rely on performance measures. To reach a required achievement threshold students may make use of additional resources, such as private tutoring. We investigate how the use of private tutoring relates to the transition probability to an academically demanding post compulsory school and the probability to successfully pass through this school, controlling for the students competencies after tutoring, but before the transition. Using PISA and linked register data from Switzerland, we find that students who had private tutoring before the transition are more likely to fail in the selective school than students who had the same competencies without tutoring.

We empirically investigate the link between parental involvement and shaping of the economic preferences, attitudes and personality traits of their children. We exploit information on the risk and trust attitudes, the Big Five personality traits and locus of control of parents and their children, as well as rich information about parental efforts in the upbringing of their children from the German Socio-Economic Panel Study. Our results show that parents who are more involved in the upbringing of their children have children with more favourable attitudes and traits. These children rank higher in traits that further their success in life, and they are more similar to their parents in those attitudes, where the optimum level is more ambiguous.

This paper investigates the impact of exogenous changes in individuals' perceived economic environment on their self-stated risk attitudes by exploiting changes in media coverage of economic news. We use information on risk attitudes from the German Socioeconomic Panel and combine it with data on the average daily frequency of economic news reports during the year and the month preceding the date of the risk attitude elicitation. Using fixed effects regressions we observe effects of both long and short term changes in the media. We find that an increase in economic news in the previous year, irrespective of whether the news are bad or good, is negatively related to individuals' willingness to take risks. An increase in news that are aggregated over the previous month, however, relates to a decrease in risk aversion if the news are predominantly good. The strength of the relations depends on individuals' personal characteristics and personality traits. A positive correlation between bad news coverage and individuals' worries suggests that changes in risk perception may mediate the relation between news coverage and risk attitudes.

Envisioning the next generation of drug delivery nanocontainers requires more in- depth information on the fundamental physical forces at play in bilayer membranes. In order to achieve this, we combine chemical synthesis with physical–chemical analytical methods and probe the relationship between a molecular structure and its biophysical properties. With the aim of increasing the number of hydrogen bond donors compared to natural phospholipids, a phospholipid compound bearing urea moieties has been synthesized. The new molecules form interdigitated bilayers in aqueous dispersions and self-assemble at soft interfaces in thin layers with distinctive structural order. At lower temperatures, endothermic and exothermic transitions are observed during compression. The LC1 phase is dominated by an intermolecular hydrogen bond network of the urea moieties leading to a very high chain tilt of 52°. During compression and at higher temperatures, presumably this hydrogen bond network is broken allowing a much lower chain tilt of 35°. The extremely different monolayer thicknesses violate the two-dimensional Clausius–Clapeyron equation.

Phospholipid liposomes are archetypical self-assembled structures. To minimize the surface tension, the vesicles typically are spherical. Deciphering the bilayer code, the basic physical interactions between phospholipids would allow these molecules to be utilized as building blocks for novel, non-spherical structures. A 1,2-diamidophospholipid is presented that self-assembles into a cuboid structure. Owing to intermolecular hydrogen bonding, the bilayer membranes form an exceptionally tight subgel packing, leading to a maximization of flat structural elements and a minimization of any edges. These conditions are optimized in the geometrical structure of a cube. Surprisingly, the lateral surface pressure in the membrane is only one third of the value typically assumed for a bilayer membrane, questioning a long-standing rule-of-thumb.

Nematode-specific iso-branched sphingoid base synthesis: drug-target against parasites and genetic model system for human diseases., Sphingolipids are bio-active metabolites that show structural diversity among eukaryotes. They are essential for growth of all eukaryotic cells but when produced in an uncontrolled manner can lead to cell death and pathologies including auto-immune reactions, cancer, diabetes and neurodegeneration. Caenorhabditis elegans is an important genetic model organism both to find new drug-targets against parasitic nematodes and to study the conserved roles of sphingolipids in animals like their essential functions in very basic cellular processes ranging from maintenance of cell polarity and mitochondrial repair to growth and survival. C. elegans produces sphingoid bases which are structurally distinct from those of other animals as both iso- and anteiso-branched species have been reported. Using metabolic labeling we show that most worm sphingoid bases are iso-branched. We have synthesized the nematode-specific C17 iso-branched sphinganine and its 1-deoxy analogue and could show that both the iso-branch and the 1-hydroxyl group are essential to form functional nematode sphingolipids which are needed to maintain intestinal function. The organism specificity was examined by complementation experiments in Saccharomyces cerevisiae yeast cells lacking sphingoid base synthesis. We found that iso-branched sphingoid base did not support growth of mutant cells and was toxic to wild type yeast. 1-Deoxy sphingolipids have been linked to the hereditary disease HSAN1A and other metabolic disorders including diabetes. We found that in C. elegans the 1-deoxy analogue cannot rescue the intestinal phenotype caused by sphingoid base depletion. In fact, in wild-type animals with normal sphingoid base biosynthesis, exogenous 1-deoxy analogue had a disruptive effect on apical cytoskeletal organization of intestinal cells indicating that atypical bases can interfere with normal sphingolipid function.

Sphingolipids are bio-active metabolites that show structural diversity among eukaryotes. They are essential for growth of all eukaryotic cells but when produced in an uncontrolled manner can lead to cell death and pathologies including auto-immune reactions, cancer, diabetes and neurodegeneration. Caenorhabditis elegans is an important genetic model organism both to find new drug-targets against parasitic nematodes and to study the conserved roles of sphingolipids in animals like their essential functions in very basic cellular processes ranging from maintenance of cell polarity and mitochondrial repair to growth and survival. C. elegans produces sphingoid bases which are structurally distinct from those of other animals as both iso- and anteiso-branched species have been reported. Using metabolic labeling we show that most worm sphingoid bases are iso-branched. We have synthesized the nematode- specific C17 iso-branched sphinganine and its 1-deoxy analogue and could show that both the iso-branch and the 1-hydroxyl group are essential to form functional nematode sphingolipids which are needed to maintain intestinal function. The organism specificity was examined by complementation experiments in Saccharomyces cerevisiae yeast cells lacking sphingoid base synthesis. We found that iso-branched sphingoid base did not support growth of mutant cells and was toxic to wild type yeast. 1-Deoxy sphingolipids have been linked to the hereditary disease HSAN1A and other metabolic disorders including diabetes. We found that in C. elegans the 1-deoxy analogue cannot rescue the intestinal phenotype caused by sphingoid base depletion. In fact, in wild-type animals with normal sphingoid base biosynthesis, exogenous 1- deoxy analogue had a disruptive effect on apical cytoskeletal organization of intestinal cells indicating that atypical bases can interfere with normal sphingolipid function.

Phospholipids are at the heart and origin of life on this planet. The possibilities in terms of phospholipid self-assembly and biological functions seem limitless. Nonetheless, nature exploits only a small fraction of the available chemical space of phospholipids. Using chemical synthesis, artificial phospholipid structures become accessible, and the study of their biophysics may reveal unprecedented properties. In this article, the recent advances by our work group in the field of chemical lipidology are summarized. The family of diamidophospholipids is discussed in detail from monolayer characterization to the formation of faceted vesicles, culminating in the template-free self-assembly of phospholipid cubes and the possible applications of vesicle origami in modern personalized medicine.

Lipid bilayer membranes formed from the artificial 1,3-diamidophospholipid Pad-PC-Pad have the remarkable property that their hydrophobic thickness can be modified in situ: the particular arrangement of the fatty acid chains in Pad-PC-Pad allows them to fully interdigitate below 37 °C, substantially thinning the membrane with respect to the noninterdigitated state. Two stimuli, traversing the main phase transition temperature of the lipid or addition of cholesterol, have previously been shown to disable the interdigitated state. Both manipulations cause an increase in hydrophobic thickness of about 25 A due to enhanced conformational entropy of the lipids. Here, we characterize the interdigitated state using electrophysiological recordings from free-standing lipid-membranes formed on micro structured electrode cavity arrays. Compared to standard membranes made from 1,2-diphytanoyl-sn-glycero-3-phosphocholin (DPhPC), pure Pad-PC-Pad membranes at room temperature had lowered electroporation threshold and higher capacitance. Ion channel formation by the peptide Gramicidin A was clearly facilitated in pure Pad-PC-Pad membranes at room temperature, with activity occurring at significantly lower peptide concentrations and channel dwell times increased by 2 orders of magnitude with respect to DPhPC-membranes. Both elevation of temperature beyond the phase transition and addition of cholesterol reduced channel dwell times, as expected if the reduced membrane thickness stabilized channel formation due to decreased hydrophobic mismatch.

Liposomes of specific artificial phospholipids, such as Pad-PC-Pad and Rad-PC-Rad, are mechanically responsive. They can release encapsulated therapeutics via physical stimuli, as naturally present in blood flow of constricted vessel segments. The question is how these synthetic liposomes change their structure in the medically relevant temperature range from 22 to 42 °C. In the present study, small-angle neutron scattering (SANS) was employed to evaluate the temperature-induced structural changes of selected artificial liposomes. For Rad-PC-Rad, Pad-Pad-PC, Sur-PC-Sur, and Sad-PC-Sad liposomes, the SANS data have remained constant because the phase transition temperatures are above 42 °C. For Pad-PC-Pad and Pes-PC-Pes liposomes, whose phase transitions are below 42 °C, the q-plots have revealed temperature-dependent structural changes. The average diameter of Pad-PC-Pad liposomes remained almost constant, whereas the eccentricity decreased by an order of magnitude. Related measurements using transmission electron microscopy at cryogenic temperatures, as well as dynamic light scattering before and after the heating cycles, underpin the fact that the non-spherical liposomes flatten out. The SANS data further indicated that, as a consequence of the thermal loop, the mean bilayer thickness increased by 20%, associated with the loss of lipid membrane interdigitation. Therefore, Pad-PC-Pad liposomes are unsuitable for local drug delivery in the atherosclerotic human blood vessel system. In contrast, Rad-PC-Rad liposomes are thermally stable for applications within the human body.

Ischaemic heart disease and stroke are the most common causes of death worldwide. Anoxia, defined as the lack of oxygen, is commonly seen in both these pathologies and triggers profound metabolic and cellular changes. Sphingolipids have been implicated in anoxia injury, but the pathomechanism is unknown. Here we show that anoxia-associated injury causes accumulation of the non-canonical sphingolipid 1-deoxydihydroceramide (DoxDHCer). Anoxia causes an imbalance between serine and alanine resulting in a switch from normal serine-derived sphinganine biosynthesis to non-canonical alanine-derived 1-deoxysphinganine. 1-Deoxysphinganine is incorporated into DoxDHCer, which impairs actin folding via the cytosolic chaperonin TRiC, leading to growth arrest in yeast, increased cell death upon anoxia-reoxygenation in worms and ischaemia-reperfusion injury in mouse hearts. Prevention of DoxDHCer accumulation in worms and in mouse hearts resulted in decreased anoxia-induced injury. These findings unravel key metabolic changes during oxygen deprivation and point to novel strategies to avoid tissue damage and death.