Browse Articles

Dynamics of post fire plant community assembly in Doñana coastal dunes

Abstract Fire significantly contributes to the distribution, composition, and functioning of ecosystems. It is also among the most damaging disturbances, exacerbated by increasing fire intensity and extent due to climate change. However, some ecosystems, like Mediterranean scrublands, recover quickly due to species’ adaptations to frequent fire regimes. This study investigates the community assembly processes during a secondary succession following the fire in a dune system within Doñana Natural Park, Southern Spain. To achieve this, three shrub communities were characterised along a coast-to-inland gradient over two consecutive years using a Non-Metric Multidimensional Scaling ordination. Then, a set of ecophysiological and structural traits of the dominant shrub species were analysed through a Principal Component Analysis, and correlation analyses were performed to assess the relationships between the three communities and the studied traits. Finally, to investigate the spatial structure of the shrub communities, a co-occurrence network was constructed and Moran’s I analyses were conducted. The results revealed that natural secondary succession has restored shrub communities along the gradient to states similar to those existing before the fire, indicating a consistent recovery pattern. Although species composition was comparable across zones, community spatial structure and several traits varied from coastal to interior areas, with more complex co-occurrence networks observed inland. Overall, the results underline the significance of environmental filters and species interactions in shaping community assembly during secondary succession after fire. Furthermore, they highlight that post fire community responses can be predicted through mechanisms linking the regional species pool, regeneration traits, and physical heterogeneity.

Large-scale photonic chip based pulse interleaver for low-noise microwave generation

Abstract Optically generated microwaves exhibit unprecedented low noise, benefiting applications such as communications, radar, instrumentation, and metrology. To date, the purest microwave signals are produced using optical frequency division with femtosecond mode-locked lasers. However, their typical repetition rates of hundreds of MHz require multiplication methods to reach the microwave domain. Here, we introduce a miniaturized photonic integrated circuit-based interleaver, achieving a 64-fold multiplication of the repetition rate from 216 MHz to 14 GHz in Ku-Band. With the interleaver, the generated microwave power was improved by 35 dB, with a phase noise floor reduced by more than 10 folds by alleviating photodetector saturation. Based on a low-loss and high-density Si3N4 waveguides, six cascaded stages of Mach-Zehnder interferometers with optical delay lines up to 33 centimeters long are fully integrated into a compact chip. Our result can significantly reduce the cost and footprint of mode-locked-laser-based microwave generation, enabling field deployment in aerospace and communication applications.

Applied anatomy and morphology of minor salivary glands in commonly used experimental animals

Environmental control on the productivity of a heavily fished ecosystem

Phase and amplitude gradient waveguide coupled metasurfaces

Ultrafast charge-transfer-induced spin transition in cobalt-tungstate molecular photomagnets

Abstract In materials exhibiting photoinduced phase transitions, and in which both charge transfer and spin transitions occur, there has long been a debate about which process drives the phase transition. Herein, we present experimental evidence supporting an optically charge-transfer-induced spin transition (CTIST) process, as demonstrated through femtosecond optical spectroscopy in two-dimensional cyanido-bridged cobalt-tungstate photomagnets. Optical and magnetic studies revealed that the photoexcitation of the ground low-temperature (LT) Co III LS -W IV state leads to a photoinduced phase transition towards the Co II HS -W V state, which is similar to the high temperature (HT) state. Ultrafast spectroscopy further indicates that this optical excitation of the intermetallic W-to-Co charge-transfer band produces a transient photoexcited (PE) Co II LS -W V state, which decays within 130 fs through a spin transition towards the Co II HS -W V state. Here we show that the CTIST dynamics corresponds to the Co III LS -W IV (LT) → Co II LS -W V (PE) → Co II HS -W V (HT) sequence. The present work sheds a new light on understanding optical dynamics underlying the photoinduced phase transitions.

Combined detection of inhibitors of the activin receptor signaling pathways (IASPs) by means of LC-HRMS/MS for human doping control

Abstract Members of the transforming growth factor beta superfamily such as myostatin, activin A, and GDF-11, are dimeric cytokines signaling through activin receptors. They play important regulative roles in different biological processes as the formation of muscle and red blood cells. Therefore, inhibitors of the activin receptor signaling pathways (IASPs) are potential performance-enhancing agents in sports, which are included in sections S2 (“Peptide hormones, growth factors, related substances and mimetics”) and S4 (“Hormone and metabolic modulators”) of the WADA Prohibited List. Within this research project, a multiplexed detection assay for nine IASPs in doping control serum/plasma samples by means of (immuno-)affinity purification, tryptic digestion and LC-HRMS/MS was developed. The method was validated and proved to be specific and sensitive (LOD: 10–50 ng/mL). Additionally, it was modified to allow for using urine. As proof-of-concept, authentic Luspatercept serum and urine and Sotatercept serum post-administration samples were successfully analyzed. Luspatercept could be detected in both matrices up to 70 days after the initial and 7 weeks after the second dose. Sotatercept was successfully detected in a serum sample collected 43 h following injection. The presented method can be employed in doping control routine analysis as a qualitative initial testing procedure.

Developmental features and unique characteristics of peptide-specific PLZF+ innate-like T cells in mice

Abstract Peptide-specific PLZF+ innate-like T (PILT) cells are a member of the innate-like T cell family utilizing a diverse set of T cell receptor (TCR) Vβ chains. Yet there are no present studies providing clues into the developmental features of PILT cells at a transcriptome level. Here, we performed single-cell transcriptomic analyses of PILT cells and compared them to other members of the innate-like T cell family. We show that PILT cells share similar transcriptional profiles and overlapping developmental trajectories with invariant Natural Killer T (iNKT) cells. However, in contrast to iNKT cells, PILT cells display a polyclonal TCR repertoire closely resembling the one of conventional CD8 T cells, inferring MHC I restriction and a broader range of antigen specificity. We further show that artificial thymic organoid cultures (ATOC) support selection and development of PILT cells in vitro exhibiting similar transcriptional profiles to their counterparts maturing in the thymus. Moreover, using an “on-time” TCR retrogenic ATOC system, we provide evidence for an instructive role of TCR specificity in PILT cell lineage commitment and functional differentiation. Altogether, our findings provide further insights into the PILT cells unique characteristics and molecular mechanisms governing their development.

Association of the triglyceride‒glucose index with subclinical right ventricular systolic dysfunction in type 2 diabetes mellitus patients

Terahertz chiral photonic-crystal cavities for Dirac gap engineering in graphene

Abstract Strong coupling between matter and vacuum electromagnetic fields in a cavity can induce novel quantum phases in thermal equilibrium via symmetry breaking. Particularly intriguing is the coupling with circularly polarized cavity fields, which can break time-reversal symmetry (TRS) and lead to topological bands. This has spurred significant interest in developing chiral cavities that feature broken TRS, especially in the terahertz (THz) frequency range, where various large-oscillator-strength resonances exist. Here, we present a design for high-quality-factor THz chiral photonic-crystal cavities (PCCs) that achieve broken TRS using a magnetoplasma in a lightly doped semiconductor. We incorporate ab initio density functional theory calculations into the derived microscopic model, allowing a realistic estimate of the vacuum-induced gap in graphene when coupled to our chiral cavity. Our calculations show an enhancement in the light–matter interaction due to Dirac nodes and predict an energy gap on the order of 1 meV. The THz chiral PCCs offer a promising platform for exploring cavity-dressed condensed matter with broken TRS.

Immune age is correlated with decreased TCR clonal diversity and antibody response to SARS-CoV-2

Abstract Immune response to infection or vaccination is compromised with age. We aimed to examine associations between immune senescence, T and B cell clonal diversity and immunoglobulin G secretion in response to immune challenge in isolated peripheral blood mononuclear cells (PBMC) from people of different chronological ages. We isolated PBMC from 49 individuals categorised into < 35 years and > 60 years age groups. Cells were then challenged with recombinant SARS-CoV-2 spike protein or vehicle and IMMAX score was calculated for each sample from flow cytometry. Antibody response was assessed using the proxy of IgG secretion and T cell receptor and immunoglobulin framework region recombination was determined by clonality studies. We observed that individuals aged > 60 years demonstrated a higher immune ‘age’ as calculated by IMMAX score (0.75 compared with 0.48 for individuals aged < 35 years; p = < 0.0001). Immune age negatively correlated with IgG responsivity in older individuals with recent prior exposure to SARS-CoV-2 (b = -0.01; p = 0.05). Higher immune age was also negatively correlated with TCR Vd + Jd receptor diversity regardless of immune challenge (b = -0.02; p = < 0.0001 and b = -0.02; r2 = 0.0.35; p = < 0.0001 for control and exposed samples respectively). Our data demonstrate that PBMC samples from older people display a higher cellular immune age and attenuation of immune response. This suggests that future treatments targeting cellular ageing of immune cells may be a useful avenue for investigation to improve immune function in older people.

Deep evolution of carbonated magmas controls ocean island basalt chemistry

Deferential nephrotoxicity effect of lanthanum oxide nanoparticle responses to concentration and time in vivo

Optimizing structured surfaces for diffractive waveguides

Abstract We introduce universal diffractive waveguide designs that can match the performance of conventional dielectric waveguides and achieve various functionalities. Optimized using deep learning, diffractive waveguides can be cascaded to form any desired length and are comprised of transmissive diffractive surfaces that permit the propagation of desired modes with low loss and high mode purity. In addition to guiding the targeted modes through cascaded diffractive units, we also developed various waveguide components and introduced bent diffractive waveguides, rotating the direction of mode propagation, as well as spatial and spectral mode filtering and mode splitting diffractive waveguide designs, and mode-specific polarization control. This framework was experimentally validated in the terahertz spectrum to selectively pass certain spatial modes while rejecting others. Without the need for material dispersion engineering diffractive waveguides can be scaled to operate at different wavelengths, including visible and infrared spectrum, covering potential applications in, e.g., telecommunications, imaging, sensing and spectroscopy.

Fluorescence-guided ureteral identification in robotic surgery for advanced endometriosis: a comparison of junior versus senior surgeons

A self-directed Trojanbot-enzymatic nanobot in neutrobot for active target therapy of glioblastoma

Effects of polyunsaturated fatty acids on gastric cancer immunity and immunotherapy

Directly printed standing ceramic circuit boards for rapid prototyping of miniaturization and high-power of electronics

The effect of pericapsular nerve group block and lateral femoral cutaneous nerve block on postoperative recovery after hip arthroplasty

Functional recruitment and connectivity of the cerebellum is associated with the emergence of Theory of Mind in early childhood

Abstract There is accumulating evidence that the human cerebellum is heavily implicated in adult social cognition. Yet, its involvement in the development of Theory of Mind (ToM), a hallmark of social cognition, remains elusive. Using openly available functional MRI data of children with emerging ToM abilities (N = 41, age range: 3-12 years) and adults (N = 78), we show that children who pass a false-belief assessment of ToM abilities activate cerebellar Crus I-II in response to ToM events during a movie-watching task, similar to adults. This activation is not statistically significant in children who do not pass the ToM assessment. Functional connectivity profiles between cerebellar and cerebral ToM regions differ as a function of children’s ToM abilities. Notably, task-driven connectivity shifts from upstream to downstream connections between cerebellar and cerebral ToM regions from childhood to adulthood. Greater dependence on connections emerging from the cerebellum early in life suggests an important role of the cerebellum in establishing the cognitive processes underlying ToM in childhood and thus for the undisrupted development of social cognition.