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The initial dynamics of product release in terpene synthases—The case of CotB2
No full textAlthough the enzymatic mechanisms of terpene synthases have been extensively characterized through experimental and computational studies, the atomistic details underlying the product release process have remained elusive. In this study, we present the first atomistic simulations of the initial stages of product release in a terpene synthase, using the bacterial diterpene cyclase CotB2 as a model system. CotB2 catalyzes the complex cyclization of geranylgeranyl diphosphate (GGDP) to the tricyclic diterpene cyclooctat-9-en-7-ol in a single active site through an 11-step reaction cascade. Our MD simulations focus on three model systems representing CotB2 with bound GGDP and cyclooctat-9-en-7-ol, the latter in two states—with the diphosphate fully deprotonated (P2O74−) and protonated diphosphate (HP2O73−). Analysis of the MD trajectories clearly shows that product release is initiated by the dislocation of the diphosphate group, which in turn triggers active site opening via coordinated C-terminal motions. Notably, protonation of the diphosphate moiety appears to be the key event that weakens its interactions with the active site and enables product release. These findings provide crucial mechanistic insight into the final phase of terpene biosynthesis and open new avenues for rational enzyme engineering targeting product release
The temporal dynamics of the association between daily physical activity and life satisfaction
No full textPurpose
Life satisfaction (LS) is increasingly recognized as a crucial indicator and predictor of health and well-being across the lifespan. The impact of LS may be enhanced through physical activity (PA), although studies exploring the dynamic and bidirectional nature of the relationship are scarce. One principal goal of this project is to examine the dynamic, personalized interactions between LS and PA and exercise identity (the degree to which exercise is a fundamental aspect of one’s self-concept) in geographic areas with different air pollution loads.
Method
We used data from a 12-month prospective cohort study (N = 1314, mean age = 38.09 [12.55]; range 18-65) with four 2-week intensive measurement bursts to evaluate the bidirectional relationship between LS (assessed at the end of the day) and PA (assessed by Fitbit Charge 3 or 4 throughout the day). The sample included both active (runners; n = 747, 57%) and inactive (n = 567, 43%) individuals living in Moravia-Silesia and South Bohemia, geographic areas with different levels of air pollution. A dynamic Bayesian model based on an extension of the vector autoregressive model was used to estimate both lagged and contemporaneous associations between LS and PA.
Results
There were meaningful autoregressive effects of first order for both LS (β = 0.394) and PA (β = 0.316), and a within-person contemporaneous association between LS and PA (β = 0.087) that was also associated with temporal factors and trends (weekly and monthly seasonal variation, day in study), gender, age, and exercise identity.
Conclusion
This study highlights the importance of periodicity on 2 temporal scales for both PA and LS, with age and gender also playing crucial roles. The findings underscore the importance of tailored, context-aware interventions to sustain engagement and enhance well-being through PA
DEPRISK Deportation Database: Methodological Note
No full textThe project “Immigration Enforcement Across the World: Drivers and Consequences of Deportation Risk (DEPRISK)” created a country-by-country database on annual deportation corridors by collecting administrative data from governmental sources in the deporting countries, both through publicly available statistics and via official requests for access to information. The database currently includes bilateral data from 42 deporting countries, including most OECD countries, spanning the period from 2000 to 2023, encompassing 7,200 deportation corridors. This methodological note describes the variables of the DEPRISK database and the challenges that arose from joining data across countries with different legal terms, procedures, and reporting systems. The country annexe presents the country-specific legal terms and data sources, and justifies all steps and decisions taken in creating variables.September 202
Player-Reported Perceptions of Lameness Risks and Contributing Factors for Polo Horses: Results from a Survey
No full textPolo is an equestrian sport with a long tradition, but to date there is little scientific data on health risks, particularly lameness. In an international online survey, 145 polo players (47.6% female, 52.4% male) with an average of 13.4 years of playing experience were questioned about lameness risks and influencing factors. The respondents reported a median of six horses, most frequently mares as their best-performing and healthiest animals. Horse age was significantly associated with the risk of lameness, increasing by approximately 19.5% per year (OR = 1.195; p = 0.030) and differed depending on the breed of horse. Player-related variables such as age, sex, level of experience and type of husbandry had no significant influence. Risk perception was only associated with the handicap: players with a higher handicap rated the risk of injury as lower. Sex, age and horse ownership were not relevant. Unfavourable ground conditions were cited as the most common cause of injury (58.6%). The results show that players believe key predictors of lameness, in particular the age and breed of the horses, are objective factors, while subjective risk assessments are primarily influenced by the players’ level of experience. Further studies are necessary to improve horse health in polo and to enable preventive measures
Pseudohermaphroditismus masculinus internus bei einem Rothirsch
No full textDigitalisat der Ausgabe von 1920, erschienen 202
SI-traceable total analysis of nitrate and nitrite by isotope dilution optical spectroscopy and its application to Berlin surface waters
No full textAccurate nitrate and nitrite data support water-quality regulation, yet routine methods rely on external calibration and rarely achieve SI traceability. We report a calibration-free determination of nitrate and nitrite by combining isotope dilution with high-resolution continuum-source graphite furnace molecular absorption spectrometry (ID-HR-CS-GF-MAS). A 15N-enriched nitrate spike (its concentration verified by reverse isotope dilution against the standard reference material NIST 3185) provides the SI link, and it is gravimetrically added to samples; nitrate and residual nitrite are converted in situ to nitric oxide (NO), whose 215 nm band is recorded at a pixel resolution of λ/Δλ ≈ 140 000. The 0.2127 nm shift between 14NO and 15NO electronic spectra is resolved, and a three-latent-variable partial least squares regression model yields the 15N/14N ratio with 0.3% precision. Instrumental LoD values of 4.8 ng (14N) and 3.2 ng (15N) translate to a method LoD of 4.8 ng of nitrogen (equivalent to 1.05 mg L−1 NO3− for a 20 μL aliquot). The furnace program allows for successive drying/pyrolysis loops, so additional 20 μL aliquots can be layered onto the graphite platform. Alternatively, a 10 mL anion-exchange solid-phase extraction step concentrates nitrate and nitrite fivefold, allowing for the analysis of even lower sample concentrations. Results for four certified reference materials (2.9 to 1000 mg L−1 NO3−) agreed with certified values, giving relative expanded uncertainties of 2 to 4%. Analysis of twenty Berlin surface-water samples revealed concentrations ranging from 0.10 to 7.3 mg L−1 NO3−, indicating that the Panke River and Teltow Canal are the primary sources of nitrogen. ID-HR-CS-GF-MAS thus delivers ID-MS-level accuracy in a few minutes per run with bench-top optics, and, with optional on-platform or SPE pre-concentration, extends SI-traceable nitrate/nitrite monitoring into the low-ng regime
Continuum-electron interferometry for enhancement of photoelectron circular dichroism and measurement of bound, free, and mixed contributions to chiral response
No full textWe develop photoelectron interferometry based on laser-assisted extreme ultraviolet ionization for flexible and robust control of photoelectron circular dichroism in randomly oriented chiral molecules. A comb of XUV photons ionizes a sample of chiral molecules in the presence of a time-delayed infrared or visible laser pulse promoting interferences between components of the XUV-ionized photoelectron wave packet. In striking contrast to multicolor phase control schemes relying on pulse shaping techniques, the magnitude of the resulting chiral signal is here controlled by the time delay between the XUV and laser pulses. Furthermore, we show that the relative polarization configurations of the XUV and IR fields allow for disentangling the contributions of bound and continuum states to the chiral response. Our proposal provides a simple, robust, and versatile tool for the control of photoelectron circular dichroism and experimentally feasible protocol for probing the individual contributions of bound and continuum states to the photoelectron circular dichroism in a time-resolved manner
Mass spectrometry detects folding intermediates populated during urea-induced protein denaturation
No full textProtein folding stability can be probed using urea, a chaotropic agent that disrupts non-covalent interactions at molar concentrations. The denaturation process is typically monitored via optical spectroscopy, which provides ensemble-averaged measurements and may struggle to resolve folding intermediates. In contrast, electrospray ionization mass spectrometry (ESI-MS) captures a non-averaged snapshot of all populated assembly and folding states within a protein conformational ensemble. However, high urea concentrations have traditionally been considered incompatible with ESI. Here, we leverage recent advancements in nano ESI emitter design, utilizing well-defined small-diameter emitters which enables protein charge states to be resolved from solutions containing up to 8 M urea. This approach allows us to directly detect the disruption of native tertiary and quaternary structures and to monitor stability changes in response to solution pH and ligand binding. We demonstrate this using single-domain proteins that follow simple two-state unfolding pathways, as well as more complex multidomain proteins and multimeric protein complexes. Our results show strong agreement with conventional urea–denaturation curves obtained via optical spectroscopy, while also providing enhanced resolution of intermediate folding and assembly states that are challenging to capture using traditional methods
From Funding Equity Initiatives to Research Productivity: Quantifying the Impact of NSF ADVANCE Awards on Recipients’ Publication Trajectories
No full textService work in academia, including organizational change efforts, often competes with time for research, potentially affecting academic careers (tenure, promotion, and pay) through slowed publication productivity. However, little is known about how involvement in such efforts affects publication strategies or whether external funding mitigates the potentially negative impacts on research activity. The authors examine changes in publication trajectories among academics participating in the National Science Foundation ADVANCE program, an externally funded gender equity initiative. Using bibliometric data and a matched sample, the authors find that scholars involved in ADVANCE awards published significantly more articles within the first four years after receiving funding. This increase cannot be fully attributed to shifts in research focus, such as publications on gender, or changes in collaboration patterns. Instead, ADVANCE resources created a spillover effect, boosting publications in gender equity while also enhancing productivity in scholars’ primary research areas. These findings suggest that external and institutional resource allocation can offset the additional burdens associated with organizational change work, enabling academics to maintain active research careers while contributing to sustainable change initiatives. This highlights the critical role of robust resource provision in supporting faculty members engaged in organizational change
What responses from European Union Law?
No full textThe proceedings of a seminar held on June, 20, 2024 delves into the phenomenon of insurance-based investment products (so-called IBIPs).
The analysis of the jurisprudence of the Court of Justice of the European Union serves as the starting point for addressing the most relevant issues related to the distribution of IBIPs. The most significant rulings of the Luxembourg Court are thus, firstly, clarifying the application scope of the sector-specific regulations on IBIPs, as well as establishing the differences between the specialized rules provided for the insurance sector and those applicable to other contracts and regulated markets (such as the financial market, broadly speaking).
Secondly, an attempt is made to understand how the issues arising from the circulation of these hybrid products can find efficient solutions through the adoption of intersectoral European disciplines, such as those concerning the protection of retail customers – for example, Directive 93/13/EEC on unfair terms in consumer contracts – and the prohibition of unfair commercial practices (Directive 2005/29/EC).
In this context, the role played by the Court's precedents can only be appreciated.
On the one hand, the interpretative effort of the European judge aims to ensure the so-called effet utile of Union law. On the other hand, the harmonizing scope of the decisions constitutes a necessary reference to reinforce the project of the Capital Market Union, in this case, applied to the insurance sector