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Mitigating Sea Surface Fading with D-MIMO : Experimental Validation
No full textThe performance of wireless communications at sea are often limited by fading caused by reflections at the sea surface. The reliability could potentially be improved by employing multiple antennas. We have conducted massive multiple-input multiple-output (MIMO) measurements at sea in order to evaluate the performance. The measurements were conducted at 5.6 GHz with 64 dual-polarized antennas, which were distributed vertically in groups of eight antennas. We evaluated the CDF of the maximum-ratio combined channel gain for different number of antennas, and compared distributed and co-located antenna configurations. We conclude that having distributed antennas is key to reduce the channel fading by a significant amount. Additionally, optimizing antenna spacing can significantly minimize fading without requiring a large number of antennas. In our scenario, the channel fading could be reduced by 15 dB by employing only three distributed antennas, showing the potential of distributed MIMO systems to improve reliability in maritime communications
Outcomes following repair of acute type A aortic dissection in patients with cerebral malperfusion
No full textObjectives: Patients with acute type A aortic dissection (ATAAD) presenting with cerebral malperfusion have significantly poorer postoperative outcomes, making the decision whether to perform acute surgery difficult. The aim of this study was to investigate types of neurological symptoms and radiological findings and their association with permanent neurological injury and mortality following ATAAD repair. Methods: This was a single-center, retrospective, observational study. A total of 629 patients underwent ATAAD surgery between January 1998 and December 2023 at Skåne University Hospital, Lund, Sweden. Of these, 93 (14.7%) presented with cerebral malperfusion and constituted the study population. The primary endpoints were clinical neurological injury and 30-day mortality. Results: Overall 30-day mortality was 25.0%. Fifty-two patients (57.1%) had persisting neurological deficit. Patients with postoperative neurological deficit had significantly higher 30-day mortality than patients without postoperative neurological deficit (37.3% vs 5.1%, p > 0.001). Common carotid artery dissection and carotid artery occlusion were significantly more frequent in patients who developed postoperative neurological injury. Preoperative hemiparesis/hemiplegia was associated with a significant increase of persisting neurological deficits, and unconsciousness was associated with a significant increase in 30-day mortality or persisting neurological deficits. After repair, 52.2% of patients showed an improvement in their clinical neurological status. Conclusion: In ATAAD patients who present with cerebral malperfusion, the risk of permanent neurological deficit and 30-day mortality is high, but a significant proportion of patients survive and more than half demonstrate an improved neurological state postoperatively
Functional characterisation of traditional Andean freeze-sun dried potato derivatives, Chuño and Tunta: Resistant starch, probiotic fermentation, and production of SCFA and GABA as bioactive metabolites
No full textChuño (black) and tunta (white) are two ancient potato derivatives traditionally produced in the high-altitude Andean region through a natural freezing, pressing, washing, and sun-drying process that preserves the tubers for long-term storage. The present study investigates the resistant starch (RS) content, antioxidant capacity, and bioactive metabolites produced by fermentation with probiotic bacteria. The RS content in dry matter chuño (52.63 g/100 g) and tunta (46.39 g/100 g) was found to be higher than that in native potatoes (36.66 g/100 g). The fermentation with Lacticaseibacillus rhamnosus, Lacticaseibacillus casei, Levilactobacillus brevis, and Propionibacterium freudenreichii resulted in the production of γ-aminobutyric acid (GABA) and short-chain fatty acids (SCFAs). Fermented chuño produced higher levels of SCFA and GABA. These properties provide an additional functional property to chuño, which also has an interesting amino acid profile and protein content. These findings establish a foundation for incorporating Andean potato derivatives into functional food formulations
Heterogeneity of the intestinal mononuclear phagocyte compartment in health and inflammatory bowel disease
No full textUnderstanding of mononuclear phagocyte (MNP) diversity in the human intestine and the alterations this compartment undergoes in inflammation remains incomplete. Here, we used single-cell RNA sequencing, cellular indexing of trancriptomes and epitopes by sequencing, flow cytometry, and imaging to explore MNP heterogeneity in human ileal and colonic laminae propriae (LPs) in health and Crohn's disease (CD). In addition to monocytes, macrophage subsets, and conventional type 1 dendritic cells (cDC1s) and cDC2s, we found a CD1c + cDC subset with transcriptional features of DC3s. Using computational tools, we identified monocyte-to-macrophage trajectories as well as putative subset-specific DC precursors. We further showed that LP CCR7 + cDCs are increased in CD and provided evidence that these cells arise from intestinal cDC2s/DC3s but not cDC1s. Collectively, these findings extend our current understanding of intestinal MNP diversity and development, highlighting both tissue-specific and inflammation-induced changes in MNP composition and function
Dual conformational emission and vibrational coherence in a sulfone-embedded narrowband emitter
No full textOrganic luminescent narrowband emitters have emerged as promising candidates for wide-color-gamut displays. However, the comprehensive photo-induced structural and vibrational dynamics responsible for the spectral broadening remain poorly understood. In this study, ultrafast spectroscopy is employed to elucidate the excited state dynamics of a sulfone-embedded narrowband emitter, 2tCPD. An intrinsic dual emission, which originates from a reversible conformational transition between boat and chair structures on a timescale of ∼100 ps, is revealed. In aromatic toluene solution, the metastable chair conformation is stabilized by forming a sandwich-like toluene–2tCPD–toluene complex through weak π–π interaction, thereby switching the dominant emission to the chair form. Furthermore, the direct observation of coherent oscillations enables the visualization of vibronic coupling in 2tCPD, where the key vibrational mode at 180 cm−1 oscillates along the excited-state potential energy surface of the boat conformation. This mode, which involves the bending vibration of sulfone and out-of-plane bending of carbonyl and peripheral phenyl groups, mainly drives the structural reorganization during the electronic transition. These findings provide mechanistic insights into conformation-dependent emission in narrowband emitters and underscore the crucial vibrational information in guiding the molecular design toward high color-purity organic fluorophores
Senolytic Interventions for Type 2 Diabetes : Current Evidence and Future Directions
No full textCellular senescence, a phenomenon characterized by the accumulation of dysfunctional, metabolically active cells, is increasingly recognized to be a key player in aging-related metabolic disorders. It is accelerated by hyperglycemia through various molecular pathways, positioning it as a critical mechanism in the pathophysiology of type 2 diabetes mellitus (T2D) and a potential therapeutic target. Emerging evidence from animal and clinical studies suggests that the usage of senolytic drugs, which selectively deplete senescent cells, can improve blood glucose regulation and mitigate diabetic complications. However, despite the conceptual feasibility of this approach, several challenges remain in their translation to the clinic: the molecular mechanisms underlying the pathogenicity of cellular senescence in vivo remain incompletely understood, and organ-specific effects of senolytic administration are yet to be fully elucidated to ensure their safety and efficacy in clinical applications. This review explores the characteristics of cellular senescence and the senescence-associated secretory phenotype (SASP) in key tissues involved in glucose homeostasis, including the pancreas, liver, adipose tissue, and skeletal muscle and the potential applications of targeting cellular senescence as a therapeutic strategy for T2D management
Hybrid Nature of Metastable Nonradiative Recombination Centers in Perovskites : Merging Shallow and Deep Defect States
No full textMetastable nonradiative centers (supertraps) are significant energy loss channels in perovskite optoelectronic devices. In their active state, supertraps induce substantial energy loss through nonradiative recombination of free charge carriers. Transitions between active (energy loss) and passive (no energy loss) states result in photoluminescence (PL) blinking on timescales from milliseconds to seconds. The presence of blinking allowed us to investigate the active states of supertraps by extracting their time-dependent quenching efficiency functions on microsecond timescales from PL decay kinetics. These functions, unique to each supertrap, reveal how transitions from passive to active states modify the PL decay curve. Surprisingly, microcrystals often contain supertraps with different properties that effectively quench PL on different timescales relative to the excitation pulse: some start to quench the prompt PL immediately after excitation, while others effectively quench only the delayed PL after several microseconds. This leads to significant differences in PL blinking behavior when comparing prompt and delayed PL components. All these are inconsistent with the common view on the active state of a supertrap as a single deep energy level in the band gap. Instead, we suggest that the active state is a complex nonradiative center comprising a shallow and a deep energy level. These two-level centers likely form through the temporary association of individual defects, with variations in their quenching dynamics attributed to differences in energy levels, geometry, and local environment. By identifying supertraps with distinct time-dependent quenching dynamics, this work provides insights into defect engineering strategies that could reduce nonradiative losses in optoelectronic perovskite devices
Remarks on the one-point density of Hele-Shaw β-ensembles
No full textIn this note, we prove equicontinuity for the family of one-point densities with respect to a two-dimensional Coulomb gas at an inverse temperature β ≥ 1=2 confined by an external potential of Hele-Shaw (or quasi-harmonic) type. As a consequence, subsequential limiting Lipschitz continuous densities are defined on the microscopic scale. There are several additional results, for example comparing the one-point density with the thermal equilibrium density
