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Onderzoekers vinden het vaak moeilijk om de juiste patiëntvertegenwoordigers te vinden die aansluiten bij hun behoeften aan ervaringskennis. We bieden onderzoekers en patiënten praktische tips om ‘vraag en aanbod’ op elkaar af te stemmen, gebaseerd op onze eigen ervaringen als patiëntvertegenwoordiger in onderzoek. Alle auteurs begonnen als onervaren patiënt, ouder of mantelzorger, een identiteit die zich ontwikkelde via een proces van groei door tegenslag. We introduceren vier stadia van persoonlijke groei in de context van onderzoek. We doen aanbevelingen voor een eerste gesprek en voor het afstemmen van onderlinge verwachtingen, zodat iedere patiënt kan bijdragen met ervaringen, kwaliteiten en vaardigheden.

The Molecular Evolutionary Genetics Analysis (MEGA) software has matured to contain a large collection of methods and tools of computational molecular evolution. Here, we describe new additions that make MEGA a more comprehensive tool for building timetrees of species, pathogens, and gene families using rapid relaxed-clock methods. Methods for estimating divergence times and confidence intervals are implemented to use probability densities for calibration constraints for node-dating and sequence sampling dates for tip-dating analyses. They are supported by new options for tagging sequences with spatiotemporal sampling information, an expanded interactive Node Calibrations Editor, and an extended Tree Explorer to display timetrees. Also added is a Bayesian method for estimating neutral evolutionary probabilities of alleles in a species using multispecies sequence alignments and a machine learning method to test for the autocorrelation of evolutionary rates in phylogenies. The computer memory requirements for the maximum likelihood analysis are reduced significantly through reprogramming, and the graphical user interface has been made more responsive and interactive for very big data sets. These enhancements will improve the user experience, quality of results, and the pace of biological discovery. Natively compiled graphical user interface and command-line versions of MEGA11 are available for Microsoft Windows, Linux, and macOS from www.megasoftware.net.

Angiogenesis is a critical, fine-tuned, multi-staged biological process. Tip-stalk cell selection and shuffling are the building blocks of sprouting angiogenesis. Accumulated evidences show that tip-stalk cell selection and shuffling are regulated by a variety of physical, chemical and biological factors, especially the interaction among multiple genes, their products and environments. The classic Notch-VEGFR, Slit-Robo, ECM-binding integrin, semaphorin and CCN family play important roles in tip-stalk cell selection and shuffling. In this review, we outline the progress and prospect in the mechanism and the roles of the various molecules and related signaling pathways in endothelial tip-stalk cell selection and shuffling. In the future, the regulators of tip-stalk cell selection and shuffling would be the potential markers and targets for angiogenesis.

The flat endface of an optical fiber tip is an emerging light-coupled microscopic platform that combines fiber optics with planar micro- and nanotechnologies. Since different materials and structures are integrated onto the endfaces, optical fiber tip devices have miniature sizes, diverse integrated functions, and low insertion losses, making them suitable for all-optical networks. In recent decades, the increasing demand for multifunctional optical fibers has created opportunities to develop various structures on fiber tips. Meanwhile, the unconventional shape of optical fibers presents challenges involving the adaptation of standard planar micro- and nanostructure preparation strategies for fiber tips. In this context, researchers are committed to exploring and optimizing fiber tip manufacturing techniques, thereby paving the way for future integrated all-fiber devices with multifunctional applications. First, we present a broad overview of current fabrication technologies, classified as “top-down,” “bottom-up,” and “material transfer” methods, for patterning optical fiber tips. Next, we review typical structures integrated on fiber tips and their known and potential applications, categorized with respect to functional structure configurations, including “optical functionalization” and “electrical integration.” Finally, we discuss the prospects for future opportunities involving multifunctional integrated fiber tips.

Background Placement of a transjugular intrahepatic portosystemic shunt (TIPS) is an effective treatment for portal hypertension. Overt hepatic encephalopathy (oHE) is a complication after TIPS associated with increased morbidity. Elevated ratio of plasma ammonia (AMM) levels compared to the local upper limit of normal (ULN) has been associated with oHE, hepatic complications and increased mortality in patients with cirrhosis without TIPS. The role of AMM in risk stratification of post‐TIPS oHE is unclear. Objective To investigate the role of AMM in the prediction of oHE in patients receiving TIPS placement. Methods Patients with TIPS placement were recruited within a prospective observational study protocol with follow‐up (FU) visits at 1, 3, 6, and 12 months after TIPS. Post hoc analyses of AMM levels for the association with the primary (oHE) and secondary endpoints (hepatic decompensation, infections, death/liver transplantation) during the first year after TIPS placement were performed. Results Of 188 patients with TIPS placement, 148 patients with available baseline AMM levels were included. During follow‐up, 37% (55/148) of patients developed oHE. In multivariable competing risk analysis, baseline AMM/ULN (HR 2.03 [CI 1.42–2.89], p = 0.001) and Freiburg index of post‐TIPS survival (FIPS) score (HR 1.52 [CI 1.03–2.24], p = 0.037) were independently associated with oHE. The published cut‐off AMM/ULN > 1.4 showed comparable results (HR 2.40 [CI 1.24–4.65], p = 0.01). AMM at FU1 was available in 100 patients, of whom 28% (28/100) developed oHE after FU1. In multivariable competing risk analysis, AMM/ULN (HR 5.48 [CI 2.37–12.67], p < 0.001), psychometric hepatic encephalopathy score (HR 0.86 [0.78–0.96], p = 0.005) and FIPS (HR 3.57 [CI 1.79–7.14], p < 0.001) at FU1 were independently associated with oHE after FU1. No significant association between AMM/ULN and the secondary endpoints was detected. Conclusion AMM levels before TIPS are independently associated with oHE after TIPS placement. AMM levels may serve as an additional marker for risk stratification of patients. Trial Registration Clinical trial number NCT04801290 Key Summary Summarize the established knowledge on this subject: ◦ Overt hepatic encephalopathy (oHE) is a relevant complication following transjugular intrahepatic portosystemic shunt (TIPS) placement. ◦ Overt HE is associated with increased morbidity and impaired quality of life. ◦ Elevated plasma ammonia levels have been associated with oHE, hepatic complications and increased mortality in patients with cirrhosis without TIPS. ◦ Its role in the risk stratification of patients with TIPS is unclear. What are the significant and/or new findings of this study? ◦ Elevated plasma ammonia levels before TIPS are associated with oHE after TIPS placement. ◦ In particular, the ratio of plasma ammonia levels compared to the local upper limit of normal is independently associated with oHE development after TIPS. ◦ Plasma ammonia levels may serve as an additional marker for risk stratification of patients receiving TIPS as they help to identify high‐risk patients requiring intensified oHE‐preventive measures.

The root tip zone is regarded as the principal action site for iron (Fe) toxicity and is more sensitive than other root zones, but the mechanism underpinning this remains largely unknown. We explored the mechanism underpinning the higher sensitivity at the Arabidopsis root tip and elucidated the role of nitric oxide (NO) using NO-related mutants and pharmacological methods. Higher Fe sensitivity of the root tip is associated with reduced potassium (K+) retention. NO in root tips is increased significantly above levels elsewhere in the root and is involved in the arrest of primary root tip zone growth under excess Fe, at least in part related to NO-induced K+ loss via SNO1 (sensitive to nitric oxide 1)/SOS4 (salt overly sensitive 4) and reduced root tip zone cell viability. Moreover, ethylene can antagonize excess Fe-inhibited root growth and K+ efflux, in part by the control of root tip NO levels. We conclude that excess Fe attenuates root growth by effecting an increase in root tip zone NO, and that this attenuation is related to NO-mediated alterations in K+ homeostasis, partly via SNO1/SOS4.

While multiple experiments have demonstrated that trees exposed to elevated CO₂can stimulate microbes to release nutrients from soil organic matter, the importance of root‐ versus mycorrhizal‐induced changes in soil processes are presently unknown. We analyzed the contribution of roots and mycorrhizal activities to carbon (C) and nitrogen (N) turnover in a loblolly pine (Pinus taeda) forest exposed to elevated CO₂by measuring extracellular enzyme activities at soil microsites accessed via root windows. Specifically, we quantified enzyme activity from soil adjacent to root tips (rhizosphere), soil adjacent to hyphal tips (hyphosphere), and bulk soil. During the peak growing season, CO₂enrichment induced a greater increase of N‐releasing enzymes in the rhizosphere (215% increase) than in the hyphosphere (36% increase), but a greater increase of recalcitrant C‐degrading enzymes in the hyphosphere (118%) than in the rhizosphere (19%). Nitrogen fertilization influenced the magnitude of CO₂effects on enzyme activities in the rhizosphere only. At the ecosystem scale, the rhizosphere accounted for c. 50% and 40% of the total activity of N‐ and C‐releasing enzymes, respectively. Collectively, our results suggest that root exudates may contribute more to accelerated N cycling under elevated CO₂at this site, while mycorrhizal fungi may contribute more to soil C degradation.

Aim Rising air temperature and changing precipitation patterns already strongly influence forest ecosystems, yet large‐scale patterns of belowground root trait variation and their underlying drivers are poorly understood. Here, we investigated general patterns of root tip adjustments within fine‐root systems and the potential ecological implications of these patterns. Location Global. Methods We synthesize key fine‐root traits related to resource acquisition and determined their responses along climate and edaphic gradients. We specifically identified patterns of root tip abundance (number of root tips per dry biomass of fine roots ≤2 mm in diameter), and root tip density (number of root tips per soil volume) among angiosperm and gymnosperm trees to climate, edaphic gradients and stand properties. Results We found that angiosperm trees, which were more common in warmer, sometimes drier climates with more fertile soil, formed more root tips (higher root tip abundance, root tip density and higher slope of root tip density vs. fine‐root biomass) than gymnosperm trees, which lived in cooler, wetter climates with poor soil. Angiosperm and gymnosperm trees exhibited opposing trends in response to gradients in climate as gymnosperm trees tended to decrease root tip abundance and root tip density but alternatively increase mycorrhizal mycelial biomass with increasing MAT/MAP (ratio of mean annual temperature to mean annual precipitation), while angiosperm trees tended to increase root tip abundance and root tip density with increasing MAT/MAP. However, the individual trends of root tip abundance and root tip density for angiosperm and gymnosperm trees to MAT or MAP were more similar and often non‐significant. Main conclusions These results suggest disparate carbon or biomass adjustment strategies within gymnosperm and angiosperm tree fine‐root systems along climate gradients. Differences in angiosperm and gymnosperm tree adjustments in their fine‐root systems to changing environments have implications for how these plant groups are likely to perform in different environments and how their responses to future climate change should be modelled.

Due to its structural characteristics, the Kaplan turbine has a specific tip clearance between blade and chamber of the runner. This paper simulates effect of varied runner tip clearance on hydraulic performance of Kaplan turbine by CFD, and model tests validated the results. The results show that the efficiency and cavitation level of turbine will decrease with the increase of runner tip clearance within a specific range.

A ram air turbine serves as a critical emergency power system for aircraft. To mitigate aerodynamic losses from tip vortices, this study proposes three blade tip enhancement configurations: a tip plate, tip contraction, and winglet. Numerical results indicate that the tip plate slightly improves the power at low tip speed ratios (TSRs); however, at medium and high TSRs—typical of turbine operation—power gains turn negative, and thrust loads increase significantly, failing to balance the gain and load. In contrast, the tip contraction—applied to the outer 5% span—enhances the power output at medium to high TSRs, with a maximum power increase of 2.05%, and consistently reduces thrust loads across all TSRs. Its highest power–thrust net gain coefficient reaches 3.85%, indicating strong potential for optimizing power efficiency and load mitigation. The winglet achieves the greatest power enhancement, increasing the power across all TSRs, with a maximum power increase of 7.59%. However, its thrust load also increases accordingly, resulting in a power–thrust net gain coefficient lower than the tip contraction. Further optimization of the winglet parameters using an orthogonal experimental design revealed that the optimized winglet increased the power output by 8.69% compared to the baseline configuration, thereby increasing the maximum power–thrust net benefit coefficient from 1.72% before optimization to 3.95%.