Miracle-dz/UniFAR-FTUs huggingface dataset:
Ectocytosis renders T cell receptor signaling self-limiting at the immune synapse

Cytotoxic T lymphocytes (CTLs) kill virus-infected and cancer cells through T cell receptor (TCR) recognition. How CTLs terminate signaling and disengage to allow serial killing has remained a mystery. TCR activation triggers membrane specialization within the immune synapse, including the production of diacylglycerol (DAG), a lipid that can induce negative membrane curvature. We found that activated TCRs were shed into DAG-enriched ectosomes at the immune synapse rather than internalized through endocytosis, suggesting that DAG may contribute to the outward budding required for ectocytosis. Budding ectosomes were endocytosed directly by target cells, thereby terminating TCR signaling and simultaneously disengaging the CTL from the target cell to allow serial killing. Thus, ectocytosis renders TCR signaling self-limiting. Description Editor’s summary Cytotoxic T lymphocytes (CTLs) are serial killers that can destroy multiple target cells in succession. Using high-resolution three-dimensional imaging, Stinchcombe et al. found that T cell receptor (TCR) activation causes rapid membrane specialization at the immune synapse so that membrane containing activated TCRs buds off in a process known as “ectocytosis. ” As ectosomes bud off, CTLs and their target cells separate, allowing serial killing to proceed. Thus, in activated CTLs, ectocytosis renders TCR signaling self-limiting. —Stella M. Hurtley Activated T cell receptors are shed through ectocytosis, not endocytosis, at the immune synapse.
Lattice plainification advances highly effective SnSe crystalline thermoelectrics

Thermoelectric technology has been widely used for key areas, including waste-heat recovery and solid-state cooling. We discovered tin selenide (SnSe) crystals with potential power generation and Peltier cooling performance. The extensive off-stoichiometric defects have a larger impact on the transport properties of SnSe, which motivated us to develop a lattice plainification strategy for defects engineering. We demonstrated that Cu can fill Sn vacancies to weaken defects scattering and boost carrier mobility, facilitating a power factor exceeding ~100 microwatts per centimeter per square kelvin and a dimensionless figure of merit (ZT) of ~1.5 at 300 kelvin, with an average ZT of ~2.2 at 300 to 773 kelvin. We further realized a single-leg efficiency of ~12.2% under a temperature difference (ΔT) of ~300 kelvin and a seven-pair Peltier cooling ΔTmax of ~61.2 kelvin at ambient temperature. Our observations are important for practical applications of SnSe crystals in power generation as well as electronic cooling. Description Editor’s summary Thermoelectric materials interconvert heat and electricity, making them useful for a range of devices. Liu et al. added copper to tin selenide, which improved the thermoelectric and mechanical properties near room temperature (see the Perspective by Chung). Tin selenide tends to have several defects when synthesized, including tin vacancies. The copper occupies these intrinsic tin vacancies, leading to improved carrier mobility. The overall strategy creates a lattice less riddled with vacancies, which could be useful for other materials. —Brent Grocholski Introducing copper to a sodium-doped tin selenide improves the room temperature thermoelectric properties.
Reynolds number dependence of the turbulent/non-turbulent interface in temporally developing turbulent boundary layers

Abstract Direct numerical simulations (DNS) of temporally developing turbulent boundary layers are performed with a wide range of Reynolds numbers based on the momentum thickness $Re_{\theta } = 2000$–$13\,000$ for investigating the Reynolds number dependence of the turbulent/non-turbulent interface (TNTI) layer. The grid spacing in the DNS is determined carefully such that small-scale turbulent motions near the TNTI are well resolved. The outer edge of the TNTI layer, called the irrotational boundary, is detected with vorticity magnitude. The mean thicknesses of the TNTI layer, $\delta _{TNTI}$, turbulent sublayer, $\delta _{TSL}$, and viscous superlayer, $\delta _{VSL}$, are found to be approximately $15\eta _{TI}$, $10\eta _{TI}$ and $5\eta _{TI}$, respectively, where $\eta _{TI}$ is the Kolmogorov scale taken in the turbulent region near the TNTI layer. The mean curvature of the irrotational boundary is also characterized by $\eta _{TI}$. The shear parameter and the shear-to-vorticity ratio show that the mean shear effects near the TNTI layer are not significant for both large and small scales. The anisotropy tensors of Reynolds stress and vorticity suggest that the turbulence under the TNTI layer tends to be isotropic at high $Re_{\theta }$, for which $\eta _{TI}/\delta \sim Re_{\theta }^{-3/4}$ is valid with the boundary layer thickness $\delta$. The surface area of the irrotational boundary is consistent with the fractal analysis of the interface, where the fractal dimension $D_f$ is found to be $2.14$–$2.20$. The present results suggest that the mean entrainment rate per unit horizontal area normalized by the friction velocity varies slowly as $Re_{\theta }^{(3/4)(D_f-2)}$ for $Re_{\theta } \geq 4000$.
Fluid–structure resonance in spanwise-flexible flapping wings

Abstract We report direct numerical simulations of the flow around a spanwise-flexible wing in forward flight. The simulations were performed at $Re=1000$ for wings of aspect ratio 2 and 4 undergoing a heaving and pitching motion at Strouhal number $St_c\approx 0.5$. We have varied the effective stiffness of the wing $\varPi _1$ while keeping the effective inertia constant, $\varPi _0=0.1$. It has been found that there is an optimal aerodynamic performance of the wing linked to a damped resonance phenomenon, that occurs when the imposed frequency of oscillation approaches the first natural frequency of the structure in the fluid, $\omega _{n,f}/\omega \approx 1$. In that situation, the time-averaged thrust is maximum, increasing by factor 2 with respect to the rigid case with an increase in propulsive efficiency of approximately 15 %. This enhanced aerodynamic performance results from the combination of larger effective angles of attack of the outboard wing sections and a delayed development of the leading edge vortex. With increasing flexibility beyond the resonant frequency, the aerodynamic performance drops significantly, in terms of both thrust production and propulsive efficiency. The cause of this drop lies in the increasing phase lag between the deflection of the wing and the heaving/pitching motion, which results in weaker leading edge vortices, negative effective angles of attack in the outboard sections of the wing, and drag generation in the first half of the stroke. Our results also show that flexible wings with the same $\omega _{n,f}/\omega$ but different aspect ratio have the same aerodynamic performance, emphasizing the importance of the structural properties of the wing for its aerodynamic performance.
Evaluation of long-term therapy in cats with feline asthma and chronic bronchitis

Abstract Objective Feline asthma (FA) and chronic bronchitis (CB) are common inflammatory diseases of the bronchial tree in cats. Even though both conditions are characterized by infiltration with different types of inflammatory cells, therapeutic measures are often similar. Little is known about potential differences in therapeutic management of these 2 airway diseases. Therefore, aim of the study was to compare initial and long-term treatment, therapeutic success, side effects, and owner satisfaction between cat with FA and those with CB. Material and methods Thirty-five cats with FA and 11 cats with CB were included in the retrospective cross-sectional study. Inclusion criteria were compatible clinical and radiographic signs and cytological evidence of eosinophilic inflammation (FA) or sterile neutrophilic inflammation (CB) in bronchoalveolar-lavage fluid (BALF). Cats with CB were excluded if evidence of pathological bacteria was present. Owners were contacted to fill out a standardized questionnaire on therapeutic management and response to treatment. Results Comparing treatment in both groups, no statistical significance was detected. Most cats were initially treated with corticosteroids as oral (FA 63%/CB 64%, P=1), inhaled (FA 34%/CB 55%, P=0.296) or injected formulations (FA 20%/CB 0%, P=0.171). In addition, oral bronchodilators (FA 43%/CB 45%, P=1), and antibiotics were given in some cases (FA 20%/CB 27%, P=0.682). For long-term management, 43% of cats with FA and 36% of cats with CB received inhaled corticosteroids (P=1), oral corticosteroids (FA 17%/CB 36%, P=0.220), and oral bronchodilators (FA 6%/CB 27%, P=0.084) as well as courses of antibiotics (FA 6%/CB 18%, P=0.238). Treatment-related side effects (polyuria/polydipsia, facial fungal infection, and diabetes mellitus) were reported in 4 cats with FA and 2 cats with CB. The majority of owners stated to be extremely or very satisfied with the response to treatment (FA 57%/CB 64%, P=1). Conclusion Significant differences regarding management and response to therapy for both diseases could not be detected. Clinical relevance Based on owner survey, chronic bronchial diseases as feline asthma and chronic bronchitis could be managed successfully with similar treatment.
Computer-assisted semen analysis in large falcons ( Falco spp.) and comparison to results of conventional semen analysis

Abstract Objective Numerous raptor species including some falcon species are facing continuous population decline in the wild and some are threatened by extinction. To support these species, captive breeding and reintroduction programs are attempted. Besides conservation, some large falcon species are commonly used in falconry and therefore bred commercially. Assisted reproduction is established in falcon breeding since the 1970s and semen analysis is an integral part to enable assessment of breeding males, inclusion or exclusion of semen donors and quality control of semen prior to artificial insemination. Conventional methods for semen analysis are widely used, but are time consuming and depend on the investigator’s experience and ability. Computer-assisted semen analysis (CASA) would offer an objective, fast and reproducible alternative, but as they have not been established in large falcon species, this was the aim of this study. Material and methods To this end, we examined in 3 breeding seasons 109 semen samples of gyr-saker hybrid falcons (n=2) and peregrine falcons (n=4) in 940 fields of view using the Minitube CASA SpermVision and compared these results to results of conventional methods of semen analysis. We used a preprogrammed setting and adapted two settings of CASA according to specific semen characteristics of falcons. Results Sperm velocity, motility and viability parameters were recorded successfully using CASA. Correlation of conventional and computer-assisted motility analysis improved during the process of adaptation of CASA settings, but both methods differed significantly due to misinterpretation of round bodies and semen impurities by CASA. Viability values of conventional and computer assisted viability analysis using SYBR-PI correlated significantly while sperm concentration did not at all. Conclusion CASA failed to replace conventional semen analysis regarding sperm motility and sperm concentration using 3 different settings, as a reliable differentiation between spermatozoa, spermatids and round bodies was not achieved. Clinical relevance Using CASA, sperm velocity parameters were measured in spermatozoa of captive-bred large falcons for the first time and may be used as orientation values.
Sternal Pin Used to Close Sternum in Infants after Cardiac Surgery

Abstract Objective A retrospective study was conducted to explore the efficacy of bioabsorbable poly-L-lactic acid sternal pins in sternal closure in infants after cardiac surgery. Methods A total of 170 infantile patients who underwent cardiac surgery were divided into the steel wire group (group A), the PDS cord group (group B), and the steel wire + sternal pin group (group C). The occurrence of the thoracic deformity was evaluated by vertebral index (VI), frontosagittal index (FSI), and Haller index (HI) values; the stability of the sternum was evaluated by detecting sternal dehiscence and displacement. Results By comparing the absolute values of the differences in VI, FSI, and HI in the three groups, it was found that the difference values of VI and HI in group C were significantly lower than those in group B ( p = 0.028 and 0.005). For the highest deformation index, the deformation rate of infants in group C before discharge and during the 1-year follow-up was lower than that in group A and group B ( p = 0.009 and 0.002, respectively). The incidence of sternal displacement in group C was also significantly lower than that in groups A and B ( p = 0.009 and 0.009). During the 1-year follow-up, there was no sternal dehiscence, and the sternum healed completely in the three groups. Conclusion The use of “steel wire + sternal pin” for sternal closure in infants after cardiac surgery can reduce the occurrence of sternal deformity, reduce anterior and posterior displacement of the sternum, and improve sternal stability.
Assessing the Value Orientations of Contributors to Virtual Citizen Science Projects

Like other crowdsourcing communities, e.g., Wikipedia, citizen science projects struggle to attract and retain long-term contributors. Long-term contributors are critical to the success of many projects; research about motivational drivers has attracted the attention of many scholars. Prior literature has argued that values are motivational constructs linked to behavioral outcomes, and value orientations differ among demographic groups and cultures. In this paper, we assess the value orientations of volunteers who contribute to Zooniverse - an online platform that connects the public and researchers who collaborate on scientific research. We conducted an online survey (N=5,436) to measure the value orientations of Zooniverse contributors using Schwartz’s’ Portrait Values Questionnaire (PVQ). We found the most salient value orientations of the population were achievement, self-direction, and security. Value prioritization differs slightly among some demographic groups. We present strategies for motivating contributions based on value orientations in the discussion.
Analysis of web accessibility evaluation tools and guidelines for monitoring according to the Directive (EU) 2016/2102

This paper presents a comparative analysis of automated web accessibility assessment tools and guidelines for monitoring of public websites and reporting according to the Directive (EU) 2016/2102. A review of previous research and our own comparative analysis revealed that the tools differ not only in functionality and result presentation, but also in violation discovery. Overviews of the Web Accessibility Directive Expert Group meetings` minutes and first reports by the European member states showed that unified monitoring and reporting do not exist between member states. We provided guidelines that would meet the minimum requirements of the Commission Implementing Decision (EU) 2018/1524, as well as guidelines for more detailed evaluation, which would improve results in terms of providing a clearer picture of the actual level of accessibility and enable efficient comparison between European member states.
Dayside Vertical Wind Reversal at Transition Altitude From E to F Regions Observed by the ICON Satellite

The Michelson Interferometer for Global High‐Resolution Thermospheric Imaging (MIGHTI) onboard the Ionospheric Connection Explorer (ICON) mission measures the neutral winds from about 88 to 310 km altitudes, which provides a good opportunity to investigate the vertical distribution of the neutral winds. In this study we used the green line of MIGHTI to focus on the wind reversal due to large vertical shears at the transition altitude from E to F regions (∼120–220 km). For the limitations of green line filter during night‐time, we therefore present only the results on the dayside from 0600 to 1800 local time (LT). Based on more than 2 years data, there were 206 and 96 orbits identified with clear wind reversal in the meridional and zonal components, respectively. These events almost covered the whole altitude of ∼120–220 km. Interestingly, such wind reversal occurs mostly (about 75%) during magnetic quiet periods with Kp less than 2. Their dependences on LT, geographic latitude (Glat) and longitude (Glon) have been further analyzed. Two different trends for the wind reversals on LT dependence have been found, for example, the mean altitude of meridional (zonal) wind reversal is higher at dawn, and then slowly decreases toward dusk; or the mean altitude of wind reversal is higher at dusk and slowly decreases toward dawn. Such two kinds of altitude trends of wind reversal are also found for the dependence on Glat, but not on Glon. In addition, we find that there are about 90% orbits with wind reversal simultaneously observed at the low E and F regions, but the altitude variations of wind reversal can be the same or opposite in the two regions, even for the same orbit. This result suggests that the wind reversals at the low E and low F regions should be different. The climatology of the wind reversals at low F region observed by ICON provides helpful constrain for the neutral wind simulation based on physical models.
Local electronic state in the half-metallic ferromagnet CrO 2 investigated by site-selective Cr 53 NMR measurements

We have made $^{53}\mathrm{Cr}$ NMR measurements on polycrystalline and single-crystalline film samples to study the local electronic state of a half-metallic ferromagnet ${\mathrm{CrO}}_{2}$ which has the rutile structure with one crystallographically equivalent Cr site. We observe two kinds of $^{53}\mathrm{Cr}$ NMR spectra in the ferromagnetic state of both the samples. An analysis on the hyperfine field shows the presence of two Cr sites with different orbital occupancies, suggesting that a local orbital order takes place with breaking the local symmetry in the rutile structure. This may be ascribed to the negative charge transfer between chromium and oxygen ions.
Distinct accessory roles of Arabidopsis VEL proteins in Polycomb silencing

Polycomb Repressive Complex 2 (PRC2) mediates epigenetic silencing of target genes in animals and plants. In Arabidopsis, PRC2 is required for the cold-induced epigenetic silencing of the FLC floral repressor locus to align flowering with spring. During this process, PRC2 relies on VEL accessory factors, including the constitutively expressed VRN5 and the cold-induced VIN3. The VEL proteins are physically associated with PRC2, but their individual functions remain unclear. Here, we show an intimate association between recombinant VRN5 and multiple components within a reconstituted PRC2, dependent on a compact conformation of VRN5 central domains. Key residues mediating this compact conformation are conserved amongst VRN5 orthologs across the plant kingdom. By contrast, VIN3 interacts with VAL1, a transcriptional repressor that binds directly to FLC. These associations differentially affect their role in H3K27me deposition: both proteins are required for H3K27me3, but only VRN5 is necessary for H3K27me2. Although originally defined as vernalization regulators, VIN3 and VRN5 co-associate with many targets in the Arabidopsis genome that are modified with H3K27me3. Our work, therefore, reveals the distinct accessory roles for VEL proteins in conferring cold-induced silencing on FLC, with broad relevance for PRC2 targets generally.
Formation of a stable RNase Y-RicT (YaaT) complex requires RicA (YmcA) and RicF (YlbF)

In Bacillus subtilis, the RicT (YaaT), RicA (YmcA) and RicF (YlbF) proteins, which form a stable ternary complex, are needed together with RNase Y (Rny), to cleave and thereby stabilize several key transcripts encoding enzymes of intermediary metabolism. We show here that RicT, but not RicA or RicF, forms a stable complex with Rny, and that this association requires the presence of RicA and RicF. We propose that RicT is handed off from the ternary complex to Rny. We show further that the two iron-sulfur clusters carried by the ternary Ric complex are required for the formation of the stable RicT-Rny complex. We demonstrate that proteins of the degradosome-like network of B. subtilis, which also interact with Rny, are dispensable for processing of the gapA operon. Thus, Rny participates in distinct RNA-related processes, determined by its binding partners, and a RicT-Rny complex is likely the functional entity for gapA mRNA maturation. IMPORTANCE The action of nucleases on RNA is universal and essential for all forms of life and includes processing steps that lead to the mature and functional forms of certain transcripts. In B. subtilis it has been shown that key transcripts for energy producing steps of glycolysis, for nitrogen assimilation and for oxidative phosphorylation, all of them crucial processes of intermediary metabolism, are cleaved at specific locations, resulting in mRNA stabilization. The proteins required for these cleavages in B. subtilis (Rny (RNase Y), RicA (YmcA), RicF (YlbF) and RicT (YaaT)) are broadly conserved among the firmicutes, including in several important pathogens, hinting that regulatory mechanisms they control may also be conserved. Several aspects of these regulatory events have been explored: phenotypes associated with the absence of these proteins have been described, the impact of these absences on the transcriptome has been documented, and there has been significant exploration of the biochemistry and structural biology of Rny and the Ric proteins. The present study further advances our understanding of the association of Ric proteins and Rny and shows that a complex of Rny with RicT is probably the entity that carries out mRNA maturation.
Optimizing the balance between heterologous acetate- and CO2-reduction pathways in anaerobic cultures of Saccharomyces cerevisiae strains engineered for low-glycerol production

In anaerobic Saccharomyces cerevisiae cultures, NADH-cofactor balancing by glycerol formation constrains ethanol yields. Introduction of an acetate-to-ethanol reduction pathway based on heterologous acetylating acetaldehyde dehydrogenase (A-ALD) can replace glycerol formation as ‘redox-sink’ and improve ethanol yields in acetate-containing media. Acetate concentrations in feedstock for first-generation bioethanol production are, however, insufficient to completely replace glycerol formation. An alternative glycerol-reduction strategy bypasses the oxidative reaction in glycolysis by introducing phosphoribulokinase (PRK) and ribulose-1,5-bisphosphate carboxylase (RuBisCO). For optimal performance in industrial settings, yeast strains should ideally first fully convert acetate and, subsequently, continue low-glycerol fermentation via the PRK-RuBisCO pathway. However, anaerobic batch cultures of a strain carrying both pathways showed inferior acetate reduction relative to a strain expressing only the A-ALD pathway. Complete A-ALD-mediated acetate reduction by a dual-pathway strain, grown anaerobically on 50 g L-1 glucose and 5 mmol L-1 acetate, was achieved upon reducing PRK abundance by a C-terminal extension of its amino-acid sequence. Yields of glycerol and ethanol on glucose were 55% lower and 6% higher, respectively, than those of a non-engineered reference strain. The negative impact of the PRK-RuBisCO pathway on acetate reduction was attributed to sensitivity of the reversible A-ALD reaction to intracellular acetaldehyde concentrations.