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The Impact of London Dispersion Interactions in Solution: Bring [a Molecular] Balance to the [LD] Force!
Full text linkThe contribution of London Dispersion (LD) to the intramolecular folding behavior of a cyclooctatetraene (COT)-based molecular balances in a variety of solvents was investigated. As part of this investigation, a well-defined system, represented by a tert-butyl dimer with an intramolecular distance of 2.44 Å was synthesized. The folding behavior of this molecular balance was then investigated in various solvents with increasing solvent polarizability (SP) to examine the contribution of London interactions. We showed that the free enthalpy of the isomerization reaction in each solvent follows approximately the same value. Gibbs free energy can be readily measured by determination of the ratio of 1,4- to 1,6-isomers. It was found that the entropy in each solvent system is responsible for the diminishing effect on ΔG values. The answer to the question of Yang et al. “How much does LD contribute to molecular recognition in solution?” is that “It depends!” The lowest ratio of 1,4- and 1,6-isomers was found in purely aliphatic solvents, this may indicate a compensating effect of dispersion interactions between the solvent and the balance. DMSO and chloroform clearly showed a preference for the 1,6-isomer. However, it became clear through additional energy decomposition analyzes (EDAs) that LD is the predominant force responsible for folding. The extension of the concept was investigated by the synthesis of adamantyl and diamantyl COT derivatives. The molecular balances still have an attractive distance of 2.4 Å for dispersion, but the polarizabilities and the expansion regarding the solvent accessible surface (SAS) of the substituents become significantly larger, which allows more interaction with the surrounding solvent. Longer aliphatic chain hydrocarbons (n-hexane, n-octane and n-dodecane) were therefore chosen as solvents to suit the growth of the derivatives. In collaboration with the Max-Planck Institute for Coal Research, computations at the highest level were carried out using implicit and explicit solvent models to determine the influence of the solvents on the folding behavior. The computational and experimental results lead to the conclusion that an adhesion occurs through the solvent and that the “rigid rotors” of the diamondoid derivatives make an exclusive contribution to the entropy. In every study, the folded derivative is always preferred
The EPPO/OLAF compendium of national procedures: Netherlands
Full text linkThis Dutch EPPO/OLAF volume examines the Dutch law governing the activities of the EPPO in the Netherlands and contains references to the EPPO Regulation and the Dutch Adoption Act (Wet van 17 maart 2021). It also explores relevant legal information for OLAF's seconded national experts, its investigators and the investigative tasks of its national partners in external investigations
The EPPO/OLAF compendium of national procedures: Austria
Full text linkThis Austrian EPPO/OLAF volume focuses on EPPO and OLAF investigations, also in relation to national partners. It contains general provisions of the Austrian Code of Criminal Procedure, the Federal Act implementing the European Public Prosecutor’s Office (EPPO-DG) (EUStA-DG EU), customs law and more
Dairy cows' responses to 2 separation methods after 3 months of cow-calf contact
Full text linkWeaning and separation remain among some of the biggest challenges for cow-calf contact systems, making the development of practical and low-stress separation methods mandatory for future success of these systems. This study aimed to compare behavioral and physiological responses of dairy cows to separation from their calves after 3 mo of full-time contact, with either the 2-step method (NF, 2 wks full-time contact while calves wore a nose flap, 1 wk fence-line contact before total separation, n = 18) or by gradual reduction of contact time between cow and calf (GR, 1 wk half day contact, 1 wk morning contact, 1 wk fence-line contact before total separation, n = 18). Vocalizations and searching behavior were observed on 4 d/wk from 1 wk before separation until 1 wk after total separation. During the same period, lying behavior and rumination time was automatically assessed via accelerometers and pressure sensors. Fecal and blood samples were collected twice per week from day −1 until +23 relative to separation start for analysis of fecal cortisol metabolites and the immune response. Milk yield in the parlor was continuously recorded. Statistical analysis was conducted using linear mixed effects models. We found no difference between the 2 separation methods in any of the examined behavioral and physiological response variables. However, a significant increase in vocalizations and searching behavior compared with baseline was present with both methods. Furthermore, there was a transient increase in physiological distress markers and a short-lived retention of milk yield at initiation of treatments, indicating that both methods induced distress for the cows. Descriptively, there were large interindividual differences between cows as well as a different temporal distribution in occurrence of behavioral responses, as GR cows vocalized most frequently during the week with fence-line contact and after total separation from the calf, while NF cows reacted strongest during the 2 wk while calves wore the nose flap. Milk yield was higher in NF than GR cows during the 2 wk while GR calves had time-restricted access to their dams and NF calves were prevented from suckling, but showed no difference afterward. However, similar evening milk yields of GR cows in the weeks with half-day and morning contact, indicated that the weekly reductions in contact time worked in a rather stepwise than gradual manner, which warrants further improvement of the GR method. Taken together, results showed that cows experienced distress during separation with the GR method, when implemented over 3 wk in 3 steps, as well as with the NF method, but differences between individuals were considerable
Nexus between agricultural challenges, farming practices, and on-farm losses of selected arable crop farmers in Nigeria: a valuation constellation approach to advancing sustainable food systems
Full text linkIntroduction: Food loss remains a critical barrier to the sustainable transformation of global food systems, especially in the Global South, where systemic inefficiencies and data gaps persist. Despite increasing attention to food loss, less than 35% of global studies focus on losses at the primary production stage, with most research centred in the Global North. This geographical and methodological imbalance limits understanding of the complex, context-specific drivers of food loss in developing regions. This study explores how agricultural challenges influence farmers’ valuation processes and practices, and how these practices may contribute to on-farm losses offering insights within the specific context studies rather than generalisations for all of Nigeria, a country facing recurrent food insecurity and malnutrition. Using a valuation constellation perspective, conceptualising food systems as dynamic networks of interconnected actors, actions, and resources, the research explores food loss as a socially and structurally mediated phenomenon rather than a linear or isolated issue.
Methods: Focus Group Discussion (FGD) were held with purposively selected farmers, facilitated by local extension agents, to gather nuanced insights into how farmers assign value and prioritise their farming practices.
Results: Findings reveal that pests and diseases are predominant challenges leading to on-farm losses among arable crop farmers. Although pests and diseases are prominent, they are embedded within a broader constellation of factors, including knowledge gaps, economic limitations, and weak institutional support. These interconnected challenges contribute to both pre- and post-harvest losses, undermining food availability and worsening hunger.
Discussion: The study emphasises the need for co-created, farmer-led strategies that address the constellation of social, material, and institutional dynamics shaping on-farm decision-making. It advocates for participatory valuation processes in policy development to ensure that farmers’ voices and rationales are structurally integrated into food system reforms. By reframing food loss through the lens of valuation constellation, this research offers a pathway towards more equitable and sustainable food system transformations
Histology-driven tailoring of surgical approaches in retroperitoneal soft tissue sarcoma : retrospective cohort study
Full text linkBackground: Histology-driven tailoring of surgical approaches for retroperitoneal soft tissue sarcoma is currently under debate. Compelling evidence assessing the role of histology-dependent extent of resection is lacking. The aim of this study was to assess outcomes of patients with primary retroperitoneal liposarcoma (LPS) or leiomyosarcoma (LMS) according to whether comprehensive (formerly ‘compartmental’) resection (CR) was performed.
Methods: A retrospective study was conducted on data from patients undergoing surgical resection for LPS and LMS at Heidelberg University Hospital (2002–2019). Parameters were compared between groups with and without CR, with subgroup analyses for grading (LPS). Kaplan–Meier and Cox regression analyses were used to identify predictors of disease-specific survival (DSS), local recurrence-free survival, and distant metastasis-free survival.
Results: In total, 119 patients with primary LPS and 46 patients with primary LMS were identified. DSS was improved in patients with LPS with CR (P = 0.049), and both DSS (P = 0.040) and distant metastasis-free survival (P = 0.041) were improved in the subgroup of patients with primary G3 LPS. In contrast, CR in patients with LMS was not associated with improved DSS, local recurrence-free survival, or distant metastasis-free survival. CR was associated with more severe postoperative complications (P = 0.021) and a longer hospital stay (P = 0.013) in patients with LPS, longer operation times (P < 0.010) in both patients with LPS and LMS, and increased blood loss (P = 0.008) in patients with LMS.
Conclusion: CR is associated with improved DSS in patients with primary LPS, which is not the case in patients with primary LMS. Given the association between CR and increased perioperative morbidity, surgical strategies for retroperitoneal soft tissue sarcoma should be individualized according to the underlying histology
N-Glycanase-1-Mangel – Charakterisierung von Genvarianten
Full text linkN-Glycanase-1-Mangel ist eine kongenitale Störung der Deglykosylierung. Die Krankheit ist durch fünf Kernsymptome geprägt: globale Entwicklungsverzögerung, Choreoathetose, Erhöhung von Leberwerten in Blutuntersuchungen, Hypo-/Alakrimie und eine progressive, sensomotorische Neuropathie. Der Erkrankung liegen Mutationen im Enzym N-Glycanase-1 (NGLY1) zu Grunde. Die N-Glycanase-1 ist vor allem an der ER-assoziierten Degradation von Proteinen beteiligt. Dabei werden N-Glykane vor der proteasomalen Degradation entfernt. Daneben interagiert es unter anderem mit NRF1/NFE2L1 und hat einen Einfluss auf unterschiedliche Signalwege. Bisher sind etwa 56 Mutationen bekannt, die zu der Erkrankung führen. Die Konsequenz jener Mutationen ist ein verminderter Spiegel von N-Glycanase-1 und somit eine verminderte Enzymaktivität. Der genaue Pathomechanismus ist jedoch Gegenstand aktueller Forschung und noch nicht abschließend geklärt. Mögliche Ansätze beziehen sich unter anderem auf eine Verminderung des oben genannten NRF1/NFE2L1 als Transkriptionsfaktor für proteasomale Gene.
Diese Arbeit hatte das Ziel, die zwei NGLY1-Varianten, R390Q und R401*, des N-Glycanase-1-Mangels zu charakterisieren. Dafür wurde zunächst eine NGLY1-KO-Zelllinie generiert. Mit dieser wurde dann das Expressionsverhalten der Genvarianten nach transienter Transfektion untersucht. Die Expression von R390Q konnte mit den verwendeten NGLY1-Antikörpern nachgewiesen werden, während dieser Nachweis bei R401* ausblieb.
Im Weiteren sollte ein Aktivitätsassay zur Bestimmung der Enzymaktivität von NGLY1 bzw. dessen Genvarianten etabliert werden. Hierzu wurde ein Venuskonstrukt, genannt ddVenus, verwendet, das erst nach Deglykosylierung durch NGLY1 fluoresziert. Damit konnte ein Rückschluss aus der Fluoreszenz auf die NGLY1-Enzymaktivität gezogen werden. Die Ergebnisse zeigten, dass die Enzymaktivität bei beiden Genvarianten hoch signifikant vermindert war. In weiteren Versuchen konnte die Aktivität von R390Q mit Betain nicht gesteigert werden, während bei R401* und der Verwendung von 50 μM Amlexanox mit einer Inkubationszeit von 48 Stunden eine Aktivitätssteigerung festgestellt werden konnte, die jedoch nicht signifikant war. Darüber hinaus wurde aufgezeigt, dass NRF1/NFE2L1 in den KO-Zellen in prozessierter Form akkumuliert. Eine Kompensation durch transiente Transfektion von NGLY1 oder der Genvarianten R390Q oder R401* konnte nicht erreicht werden
