Publications by authors named "Portmann R"

More than a third of the world's population lives in drylands and is disproportionately at risk from hydrometeorological hazards such as drought and flooding. While weather systems governing precipitation formation in humid regions have been widely explored, our understanding of the atmospheric processes generating precipitation in arid regions remains fragmented at best. Here we show, using a variety of precipitation datasets, that Rossby wave breaking is a key atmospheric driver of precipitation in arid regions worldwide.

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Mare milk has a unique protein composition that makes it a preferred option for adult and infant nutrition. Several functional properties have been attributed to this milk, but with little current evidence. In fact, knowledge on mare milk composition is still limited.

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The effect of the horn status of cows on their milk composition and quality is a controversial research topic. In this study, 128 milk samples from 64 horned and 64 disbudded Brown Swiss and Original Braunvieh cows were collected from alpine farms where both horned and disbudded cows were grazing on mountain pastures. The samples were analyzed for their detailed composition and protein digestion in a simulated in vitro digestion (INFOGEST).

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We introduce a climate intervention strategy focused on decreasing water vapor (WV) concentrations near the tropopause and in the stratosphere to increase outbound longwave radiation. The mechanism is the targeted injection of ice-nucleating particles (INP) in air supersaturated with respect to ice at high altitudes in the tropical entryway to the stratosphere. Ice formation in this region is a critical control of stratospheric WV.

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To support the transition towards more sustainable and healthy diets, viable alternatives to foods of animal origin need to be identified. Many plant-based protein sources are currently marketed with claims of minimal environmental impact, but very limited consideration has been given to their protein quality and bioavailable mineral content considering the fact that animal-based foods are typically the primary source of both in Western diets. In this study, traditionally consumed soy foods (cooked soybeans, soymilk, tofu) from different Swiss soybean cultivars were nutritionally characterized and the in vitro digestibility of individual amino acids and total protein were assessed using an in vitro model based on the static INFOGEST protocol; the protein quality was evaluated using the in vitro digestible indispensable amino acid score (DIAAS).

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  • The Hunga Tonga-Hunga Ha'apai volcano erupted on January 15, 2022, providing a unique chance to study how tropical volcanic eruptions affect the stratosphere.
  • Observations from balloons near Réunion Island indicated a significant injection of water vapor which led to increased humidity, causing rapid ozone depletion of 5% within a week.
  • The study also showed changes in chlorine compounds in the volcanic plume, enhancing our understanding of volcanic impacts on stratospheric chemistry and potential climate change effects.
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Microalgae are gaining interest as food ingredient. Assessments of functional and nutritional properties are necessary to forward their implementation. In this study, protein content and composition of eight commercially available microalgae biomasses were determined and compared to conventional food proteins.

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Screenings of cheese isolates revealed that the Latilactobacillus curvatus strain FAM25164 formed tryptamine and tyramine. In the present study, it was studied whether a tryptophan decarboxylase, which has rarely been described in bacteria, could be involved in the production of tryptamine. The genome of strain FAM25164 was sequenced and two amino acid decarboxylase genes of interest were identified by sequence comparisons and gene context analyses.

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Edible insects, such as mealworms (; TM) and crickets (; AD), are a sustainable, protein-dense novel food with a favorable amino acid profile, which might be an alternative to animal proteins. To assess the protein quality of TM and AD, we assessed the digestible indispensable amino acid scores (DIAAS), considering individual amino acids and their ileal amino acid digestibility, using an model based on the INFOGEST digestion protocol. In addition, we evaluated if various processing and food preparation steps influenced the digestibility of individual amino acids and the DIAAS values of TM and AD and compared them to chicken breast as a reference of excellent protein quality.

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Mass spectrometry has become the technique of choice for the assessment of a high variety of molecules in complex food matrices. It is best suited for monitoring the evolution of digestive processes in vivo and in vitro. However, considering the variety of equipment available in different laboratories and the diversity of sample preparation methods, instrumental settings for data acquisition, statistical evaluations, and interpretations of results, it is difficult to predict a priori the ideal parameters for optimal results.

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The function of the aminotransferase Aat (GenBank Protein WP_159211138) from FAM 18098 was studied . For this purpose, the gene was replaced with an erythromycin resistance gene using the temperature-sensitive shuttle plasmid pSET4T_Δ. The knockout was verified by PCR and genome sequencing.

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  • A study compares the protein quality and digestibility of beef burgers with plant-based veggie burgers made from soy and pea-faba proteins, focusing on how digestion affects their nutritional value.
  • Using the INFOGEST in vitro digestion protocol, the research assesses total protein digestibility and analyzes amino acids to calculate the Digestible Indispensable Amino Acid Score (DIAAS).
  • Results show that grilled beef burgers have the highest protein quality, while soy burgers are rated as a good protein source; however, grilling negatively affects the digestibility of pea-faba burgers.
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Identification of food intake biomarkers (FIBs) for fermented foods could help improve their dietary assessment and clarify their associations with cardiometabolic health. We aimed to identify novel FIBs for fermented foods in the plasma and urine metabolomes of 246 free-living Dutch adults using nontargeted LC-MS and GC-MS. Furthermore, associations between identified metabolites and several cardiometabolic risk factors were explored.

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  • The decline in liquid milk consumption in Western countries is being offset by a rise in processed dairy products and plant-based milk alternatives, which are frequently marketed as substitutes for cow's milk.
  • A study compared the nutritional content of 27 plant-based drinks to cow's milk, analyzing factors like protein, fat, vitamins, and minerals, as well as harmful residues such as glyphosate and arsenic.
  • The findings indicated that while soy drinks contained more protein and certain vitamins than milk, most plant-based alternatives were low in protein and did not match the nutrient profile and quality of cow's milk, highlighting the need for better fortification in these products.
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The FAO recommends the digestible indispensable amino acid score (DIAAS) to determine protein quality in foods, preferably tested in vivo. Here, the INFOGESTin vitrodigestion protocol was applied and supplemented with an analytical workflow allowing the assessment of protein digestibility and DIAAS calculation. The protocol was applied to selected samples WPI, zein, collagen, black beans, pigeon peas, All-Bran®, and peanuts.

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Forests can store large amounts of carbon and provide essential ecosystem services. Massive tree planting is thus sometimes portrayed as a panacea to mitigate climate change and related impacts. Recent controversies about the potential benefits and drawbacks of forestation have centered on the carbon storage potential of forests and the local or global thermodynamic impacts.

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Background: Whereas the dietary intake of industrial trans fatty acids (iTFA) has been specifically associated with inflammation, cardiovascular disease, and type 2 diabetes, understanding the impact of dietary fats on human health remains challenging owing to their complex composition and individual effects of their lipid components on metabolism. The aim of this study is to profile the composition of blood, measured by the fatty acid (FAs) profile and untargeted metabolome of serum and the transcriptome of blood cells, in order to identify molecular signatures that discriminate dietary fat intakes.

Methods: In a parallel study, the molecular effects of consuming dairy fat containing ruminant TFA (rTFA) or margarine containing iTFA were investigated.

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The identification and validation of biomarkers of food intake (BFIs) is a promising approach to develop more objective and complementary tools to the traditional dietary assessment methods. Concerning dairy, their evaluation in terms of intake is not simple, given the variety of existing foods, making it difficult to establish the association between specific dairy products consumption and the effects on human health, which is also dependent on the study population. Here, we aimed at identifying BFI of both milk (M) and yogurt (Y) in 14 healthy young (20-35 years) and 14 older (65-80 years).

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  • Large wildfires can release smoke high into the atmosphere, which may impact the stratospheric ozone layer that protects us from harmful UV radiation.
  • Data from multiple satellites showed that the 2019-2020 Australian wildfires led to decreases in nitrogen monoxide (NO) levels in the stratosphere, indicating significant chemical reactions on the smoke particles.
  • This research suggests that increasing wildfire occurrences due to climate change could hinder the recovery of the ozone layer, posing further risks to life on Earth.
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Although the composition of the human blood metabolome is influenced both by the health status of the organism and its dietary behavior, the interaction between these two factors has been poorly characterized. This study makes use of a previously published randomized controlled crossover acute intervention to investigate whether the blood metabolome of 15 healthy normal weight (NW) and 17 obese (OB) men having ingested three doses (500, 1000, 1500 kcal) of a high-fat (HF) meal can be used to identify metabolites differentiating these two groups. Among the 1024 features showing a postprandial response, measured between 0 h and 6 h, in the NW group, 135 were dose-dependent.

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Studies examining associations between self-reported dairy intake and health are inconclusive, but biomarkers hold promise for elucidating such relationships by offering objective measures of dietary intake. Previous human intervention studies identified several biomarkers for dairy foods in blood and urine using non-targeted metabolomics. We evaluated the robustness of these biomarkers in a free-living cohort in the Netherlands using both single- and multi-marker approaches.

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  • The atmospheric levels of CFC-11, a harmful ozone-depleting substance, have been decreasing since the Montreal Protocol, but there was a worrying slowdown in this decline due to unexpected emissions starting in 2013.
  • Recent data shows a significant drop in global CFC-11 emissions from 2018 to 2019, indicating a reduction in unreported production.
  • If this trend of decreasing emissions continues, it could limit future ozone depletion despite a growing reserve of un-emitted CFC-11.
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Background: As many countries lack (multi-sectoral) data on the epidemiology of agency responses to child maltreatment, they do not know if children in different regions of the country have equal chances to receive help and protection. The Optimus Study, the first nationally representative Swiss study on multi-sectoral responses to child maltreatment, examines gaps in identifying children in need and reveals opportunities for improved support and protection.

Methods: A stratified sample of 351 agencies (participation rate 81 %) in the social and health sector, public child protection, and the penal sector provided data on new cases between September 1 and November 30, 2016.

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Numerous bacteria are responsible for hydrolysis of proteins during cheese ripening. The raw milk flora is a major source of bacterial variety, starter cultures are needed for successful acidification of the cheese and proteolytic strains like Lactobacillus helveticus, are added for flavor improvement or acceleration of ripening processes. To study the impact of higher bacterial diversity in cheese on protein hydrolysis during simulated human digestion, Raclette-type cheeses were produced from raw or heat treated milk, with or without proteolytic L.

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During cheese ripening, the bacterial strain Pediococcus acidilactici FAM18098 produces the non-proteinogenic amino acid, α-aminobutyrate (AABA). The metabolic processes that lead to the biosynthesis of this compound are unknown. In this study, 10 P.

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