Tin contamination in sediments of Lake Zurich: source, spread, history and risk assessment.

Unlabelled: Industrial activities of a silk dyeing factory in Thalwil, on the shore of Lake Zurich, Switzerland, caused extreme Sn contamination of lake sediments. In this study, we determine the contamination source, spread, and age using a multiproxy approach. We used X-ray fluorescence spectroscopy (XRF) core scanning and further geochemical analyses to assess the contamination spreading and thickness in the sedimentary column.

The potential of ALFA-tag and tyramide-based fluorescence signal amplification to expand the CRISPR-based DNA imaging toolkit.

Understanding the spatial organization of genomes within chromatin is crucial for deciphering gene regulation. A recently developed CRISPR-dCas9-based genome labeling tool, known as CRISPR-FISH, allows efficient labeling of repetitive sequences. Unlike standard fluorescence in situ hybridization (FISH), CRISPR-FISH eliminates the need for global DNA denaturation, allowing for superior preservation of chromatin structure.

Conformational and Substitution Effects on the Donor and Reducing Strength of Tin(II) Porphyrinogens.

Meso-octaalkylcalix[4]pyrrolates are a class of redox-active porphyrinogen ligands. They have been well established in d- and f-block chemistry for over three decades but have only recently been introduced as ligands for p-block elements. Here, we present a study on the influence of meso-substituents on the redox chemistry of calix[4]pyrrolato stannate(II) dianions [2] (R=Me, Et).

The science behind the nose: correlating volatile organic compound characterisation with canine biodetection of COVID-19.

Background: The SARS-CoV-2 pandemic stimulated the advancement and research in the field of canine scent detection of COVID-19 and volatile organic compound (VOC) breath sampling. It remains unclear which VOCs are associated with positive canine alerts. This study aimed to confirm that the training aids used for COVID-19 canine scent detection were indeed releasing discriminant COVID-19 VOCs detectable and identifiable by gas chromatography (GC-MS).

Delineating organizational principles of the endogenous L-A virus by cryo-EM and computational analysis of native cell extracts.

The high abundance of most viruses in infected host cells benefits their structural characterization. However, endogenous viruses are present in low copy numbers and are therefore challenging to investigate. Here, we retrieve cell extracts enriched with an endogenous virus, the yeast L-A virus.

Concatenating Structural Constraint Effects at Tin for the Sequential Generation, Stabilization, and Transfer of Acyclic Aminocarbenes.

Structural constraint approaches have been employed toward different ends in recent years, from augmenting the nucleophilicity in pyramidalized low-valent p-block compounds to enhancing the Lewis acidities at planarized tetravalent p-block elements. While previous studies exploited these effects separately, this work introduces a strategy to concatenate structural constraint approaches at individual stages of a reaction sequence in a row to unlock a synthetic path unattainable by conventional methodologies. The boosted nucleophilicity resulting from the constrained tetracoordinated calix[4]pyrrolato stannate(II) dianion enables the reductive formation of sterically unprotected acyclic aminocarbenes.

Meiotic segregation and post-meiotic drive of the Festuca pratensis B chromosome.

In many species, the transmission of B chromosomes (Bs) does not follow the Mendelian laws of equal segregation and independent assortment. This deviation results in transmission rates of Bs higher than 0.5, a process known as "chromosome drive".

Vesicle budding caused by lysolipid-induced asymmetry stress.

Lysolipids such as lauroyl, myristoyl, and palmitoyl lysophosphatidylcholine (LPC) insert into the outer leaflet of liposomes but do not flip to the inner leaflet over many hours. This way, they create asymmetry stress between the intrinsic areas of the two leaflets. We have studied how this stress is relaxed with particular emphasis on the budding and fission of small (diameter 20-30 nm) daughter vesicles (DVs).

The Potential of Myrtaceae Species for the Phytomanagement of Treated Municipal Wastewater.

The use of native plants in land application systems for treated municipal wastewater (TMW) can contribute to ecological restoration. However, research on the potential of native species to manage the nutrients and contaminants contained in TMW is scarce. At a 10-hectare field site irrigated with TMW at >4000 mm yr, we investigated the distribution of nutrients and trace elements in the soil-plant system, comparing the New Zealand native Myrtaceae species and with pasture.

Shaping membrane interfaces in lipid vesicles mimicking the cytoplasmic leaflet of myelin through variation of cholesterol and myelin basic protein contents.

Myelin basic protein (MBP) is an intrinsically disordered protein and in the central nervous system (CNS) mainly responsible for connecting the cytoplasmic surfaces of the multilamellar, compact myelin. Increased posttranslational modification of MBP is linked to both, the natural development (from adolescent to adult brains) of myelin, and features of multiple sclerosis. Here, we study how a combination of this intrinsically disordered myelin protein with varying the natural cholesterol content may alter the characteristics of myelin-like membranes and interactions between these membranes.

Breath testing for SARS-CoV-2 infection.

Background: From a public health perspective, the identification of individuals with mild respiratory symptoms due to SARS-CoV-2 infection is important to contain the spread of the disease. The objective of this study was to identify volatile organic compounds (VOCs) in exhaled breath common to infection with different variants of the SARS-CoV-2 virus to inform the development of a point-of-care breath test to detect infected individuals with mild symptoms.

Methods: A prospective, real-world, observational study was conducted on mildly symptomatic out-patients presenting to community test-sites for RT-qPCR SARS-CoV-2 testing when the Alpha, Beta, and Delta variants were driving the COVID-19 pandemic.

Cryo-Electron Microscopy Snapshots of Eukaryotic Membrane Proteins in Native Lipid-Bilayer Nanodiscs.

New technologies for purifying membrane-bound protein complexes in combination with cryo-electron microscopy (EM) have recently allowed the exploration of such complexes under near-native conditions. In particular, polymer-encapsulated nanodiscs enable the study of membrane proteins at high resolution while retaining protein-protein and protein-lipid interactions within a lipid bilayer. However, this powerful technology has not been exploited to address the important question of how endogenous─as opposed to overexpressed─membrane proteins are organized within a lipid environment.

Zwitterionic fluorinated detergents: From design to membrane protein applications.

We report herein the synthesis of zwitterionic sulfobetaine (SB) and dimethylamine oxide (AO) detergents whose alkyl chain is made of either a perfluorohexyl (FH) or a perfluoropentyl (FH) group linked to a hydrogenated spacer arm. In aqueous solution, the critical micellar concentrations (CMCs) measured by surface tensiometry (SFT) and isothermal titration calorimetry (ITC) were found in the millimolar range (1.3-2.

A Thoracic Surgery-Specific Risk Assessment Model to Prevent Perioperative Venous Thromboembolism.

Background: The risk of venous thromboembolism (VTE) in patients undergoing resection in the setting of lung cancer represents a major challenge to improving postoperative outcomes. The Caprini risk assessment model has been validated in general surgery to determine a role for extended chemoprophylaxis to reduce VTE events. Our goal was to simplify this burdensome model for the unique needs of this thoracic surgical population to better guide anticoagulation decision-making.

In-store or online grocery shopping before and during the COVID-19 pandemic.

This paper presents results of a unique stated choice (SC) experiment to uncover the determinants of grocery shopping channel choice during the first wave of COVID-19 infections, where the most restrictive containment measures were in place. The choice sets were framed under regular and pandemic conditions, allowing for the estimation of pandemic-specific effects for each of the choice attributes. Our results show a significant overall increase of about 13%-points in online grocery shopping under pandemic conditions.

Electroneutral Polymer Nanodiscs Enable Interference-Free Probing of Membrane Proteins in a Lipid-Bilayer Environment.

Membrane proteins can be examined in near-native lipid-bilayer environments with the advent of polymer-encapsulated nanodiscs. These nanodiscs self-assemble directly from cellular membranes, allowing in vitro probing of membrane proteins with techniques that have previously been restricted to soluble or detergent-solubilized proteins. Often, however, the high charge densities of existing polymers obstruct bioanalytical and preparative techniques.

Azide- and diazirine-modified membrane lipids: Physicochemistry and applicability to study peptide/lipid interactions via cross-linking/mass spectrometry.

Although the incorporation of photo-activatable lipids into membranes potentially opens new avenues for studying interactions with peptides and proteins, the question of whether azide- or diazirine-modified lipids are suitable for such studies remains controversial. We have recently shown that diazirine-modified lipids can indeed form cross-links to membrane peptides after UV activation and that these cross-links can be precisely determined in their position by mass spectrometry (MS). However, we also observed an unexpected backfolding of the lipid's diazirine-containing stearoyl chain to the membrane interface challenging the potential application of this modified lipid for future cross-linking (XL)-MS studies of protein/lipid interactions.

Filling the Gap with Long -Alkanes: Incorporation of C20 and C30 into Phospholipid Membranes.

Investigating how hydrophobic molecules mix with phospholipid bilayers and how they affect membrane properties is commonplace in biophysics. Despite this, a molecular-level empirical description of a membrane model as simple as a phospholipid bilayer with long linear hydrophobic chains incorporated is still missing. Here, we present an unprecedented molecular characterization of the incorporation of two long -alkanes, -eicosane (C20) and -triacontane (C30) with 20 and 30 carbons, respectively, in phosphatidylcholine (PC) bilayers using a combination of experimental techniques (H NMR, P NMR, H-C dipolar recoupling solid-state NMR, X-ray scattering, and cryogenic electron microscopy) and atomistic molecular dynamics (MD) simulations.

Peppermint protocol: first results for gas chromatography-ion mobility spectrometry.

Theseeks to inform the standardisation of breath analysis methods. Fivewith gas chromatography-ion mobility spectrometry (GC-IMS), operating in the positive mode with a tritiumH 5.68 keV, 370 MBq ionisation source, were undertaken to provide benchmarkdata for this technique, to support its use in breath-testing, analysis, and research.

Investigating conjugated polymer nanoparticle formulations for lateral flow immunoassays.

Lateral flow immunoassays (LFI) are valuable tools for point-of-care testing. However, their sensitivity is limited and can be further improved. Nanoparticles (NP) of conjugated polymers (CPNs), also known as Pdots, are reported to be highly sensitive fluorescent probes, but a direct comparison with conventional colloidal gold-based (Au-NP) LFI using the same antibody-antigen pair is missing to date.

Breath collection protocol for SARS-CoV-2 testing in an ambulatory setting.

. The SARS-CoV-2 pandemic changed the way the society functioned. The race to develop a rapid, non-invasive, widely available test resulted in multiple studies examining the potential of breath to be that 'game changing test'.

A bioinspired glycopolymer for capturing membrane proteins in native-like lipid-bilayer nanodiscs.

Amphiphilic copolymers that directly extract membrane proteins and lipids from cellular membranes to form nanodiscs combine the advantages of harsher membrane mimics with those of a native-like membrane environment. Among the few commercial polymers that are capable of forming nanodiscs, alternating diisobutylene/maleic acid (DIBMA) copolymers have gained considerable popularity as gentle and UV-transparent alternatives to aromatic polymers. However, their moderate hydrophobicities and high electric charge densities render all existing aliphatic copolymers rather inefficient under near-physiological conditions.

Vagal Tone and Proinflammatory Cytokines Predict Feeding Intolerance and Necrotizing Enterocolitis Risk.

Background: Necrotizing enterocolitis (NEC) is the leading cause of death due to gastrointestinal disease in preterm neonates; yet, clinicians lack reliable and noninvasive predictive tools.

Purpose: We aimed to test that diminished high-frequency heart rate variability (HF-HRV) and elevated levels of proinflammatory cytokines would have utility in NEC prediction.

Methods: In this multisite prospective study, we enrolled 250 preterm (26-34 weeks' postmenstrual age [PMA]) neonates with physiological stability at 72 hours of life.