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Rapid RASER MRI
Abstract Conventional Magnetic Resonance Imaging (MRI) relies on high‐power Radio‐Frequency (RF) pulses to excite nuclear spins and in turn generate NMR signals. These pulses require large high‐power RF‐amplifiers and cause heat deposition in the tissue, which must be minimized for safety, presenting a growing problem when moving toward ever‐higher field MRI. An alternative to RF‐pulse excitation is self‐excitation of nuclear spins using Radiofrequency Amplification by Stimulated Emission of Radiation (RASER), where the nuclear spins undergo spontaneous transition, without RF excitation, from an over‐populated state to a ground state. Here, the feasibility of recording rapid proton RASER MRI images of pyrazine at low concentration (120 mM) with large matrix (128x128 pixels) in as little as 78 ms is demonstrated at 500 MHz (11.7 T). We also recorded a time‐series of images using a single bolus hyperpolarized pyrazine highlighting the feasibility of dynamic tracking. The demonstrated approach allows recording MRI scans without transmit‐receive electronics of the MRI scanner, which is highly desirable for portable MRI as well as the emerging field of hyperpolarized MRI using, e.g., HP protons, 129 Xe gas or HP 13 C labeled biomolecules as molecular tracers and imaging agents.
Investigating key drivers influencing AI-based detection and identification of plants
In recent years, AI-driven platforms have transformed citizen science by collecting and generating valuable records of living organisms for monitoring biological data. Many applications utilize visual similarity and geospatial information to identify species based on photographs. This study investigates how location impacts plant identifications made by iNaturalist, particularly in detecting invasive alien plants (IAP) that are not established in an area. We also compare the accuracy of iNaturalist and PlantNet while exploring potential biases. To assess iNaturalist’s taxonomic accuracy under varying location parameters, specimens of plants that are native and naturalized in Ontario, termed “established plants” for the purpose of this study, were collected and photographed (n = 61) and photographs of plants from Canada’s regulated pest list, which are either not present or have a very limited distribution in Canada, termed “outsider plants” for the purpose of this study were exported from iNaturalist and GBIF (n = 402). We used photographs of the established plants to compare taxonomic accuracy between applications, considering factors such as plant families, distribution status, and visible parts. A scoring system was established, and a cumulative linked mixed model was applied to analyze taxonomic accuracy. Our findings reveal that restricting location significantly hinders iNaturalist’s ability to identify IAP, highlighting the potential for missed detections. While sample size limitations prevented a robust comparison between applications, we also found significantly lower identification accuracy for species in the Poaceae family and for photographs featuring only leaves. Ultimately, recognizing the influence of location is essential for effectively monitoring IAP and leveraging iNaturalist as a tool for early detection.
Regional-specific GABAergic imbalance in cisplatin-induced neuropathy and antiallodynic effects of intraplantar baclofen in rats
Declining anthropogenic aerosols amplify Northern Hemisphere Hadley circulation weakening in the 21st century
Hidden Diradical: Conformational Switch for Solvatochromic NIR Emission With Unity Quantum Yield in Thiele's Hydrocarbon
ABSTRACT We present that halogen‐substituted and air‐stable Thiele‐type diradicaloids with folded ( 1 ) and planar ( 2 , 3 ) structures can be obtained by switching the positions of fluorine and chlorine substituents. The strongly distorted p ‐quinodimethane 1 demonstrates emission in the UV–visible/near‐infrared (UV–vis/NIR) range with a photoluminescence quantum yield (PLQY) of 100%, an exceedingly large Stokes shift of up to 2.0 eV, an excited state lifetime of 81 ns, and pronounced solvatochromic emission (from 1.81 eV in n ‐pentane to approximately 2.0 eV in dichloromethane). Dual emission in pentane, transient absorption spectroscopy, quantum chemical calculations, as well as the comparison with compounds 2 and 3 reveal that the exceptional photophysical properties of closed‐shell 1 are thanks to interconversion with its planar conformer 1 flat . The key here is that the conformer 1 flat , which is generated upon photoexcitation, excels with a pronounced singlet diradical character ( y 0 = 0.78) and a dark doubly excited (DE) S1 state. Our findings delineate how to leverage conformational equilibria to design bright luminescent materials based on hidden and thus air‐stable organic diradicals.
Pathways into homelessness and perspectives on prevention: A qualitative study of army veterans
Background Despite a national focus on ending veteran homelessness, many veterans remain homeless in the United States. Little qualitative research has explored in national samples the pathways that lead to homelessness among veterans or veteran perspectives on homelessness prevention. Methods We conducted individual semi-structured interviews with 55 US Army veterans from the national Army Study to Assess Risk and Resilience in Servicemembers-Longitudinal Study (STARRS-LS) who reported having an episode of homelessness after separating from the Army. Interviews included questions about their pathways into homelessness and what could have prevented their homelessness. Interview transcripts were analyzed for themes using a hybrid deductive-inductive approach. Results We identified three main themes as pathways into homelessness: (1) financial challenges while reintegrating into civilian life , including the subthemes of difficulty finding adequate employment and lengthy processing of VA disability benefits; (2) planning challenges around the transition, including the subthemes of lack of awareness of existing resources and personal challenges with planning; and (3) interpersonal disruptions upon reintegration , including the subthemes of loss of a primary relationship and intersections between social disruptions and having a mental illness. Notably, many participants identified connections between multiple themes as leading to homelessness after service. Veterans expressed that enrolling veterans in services prior to separation, decreasing barriers to receiving VA disability benefits, and enhancing access to mental health care would have helped prevent their homelessness. Conclusion The multiple challenges veterans identified as leading to homelessness most often began during the immediate transition period from the US Army to civilian life and are modifiable. These findings can be used to develop or enhance systems to improve prevention of homelessness among veterans.
Combined effects of depression and visual impairment on cardiovascular disease incidence in a Chinese population-based cohort
A single mutation in nonstructural protein 1 is critical for the adaptive evolution of influenza B virus
An Iridium‐Catalyzed Conia‐ene Reaction for the Diastereo‐ and Enantioselective Synthesis of Complex Ring Systems
Abstract Iridium‐catalyzed Conia‐ene reactions of α‐amino amides are described. These units undergo 6‐ or 7‐ exo cyclization onto amido‐tethered alkenes to provide benzofused N ‐heterocycles. In this process, challenging contiguous stereocenters are installed with high diastereo‐ and enantioselectivity. The method provides a versatile platform for constructing sp 3 ‐rich heterocycles, and offers unusual examples of alkenes engaging in enantio‐ and diastereoselective Conia‐ene reactions. This study adds to an emerging body of processes that exploit the directed generation of Ir‐enolates.
Genetic control of dynamic brain network reconfiguration during working memory
Working memory is fundamental to human cognition, yet the genetic contributions to dynamic brain network states during task remain poorly understood. Here, we examined static and dynamic functional connectivity in monozygotic (MZ) and dizygotic (DZ) twins performing a 2-back versus 0-back working memory task, isolating cognitive-load-specific neural processes. Static functional connectivity exhibited moderate heritability (A ≈ 0.30), predominantly in heteromodal association cortex, including the Default Mode Network (DMN) and fronto-cingulate control regions, whereas primary sensory-motor networks showed minimal genetic influence. Dynamic connectivity further distinguished mean and variance components: mean dynamic connectivity demonstrated moderate heritability (A ≈ 0.23–0.30) across DMN–attention and DMN–frontal control interactions, whereas variance of dynamic connectivity showed the strongest genetic effects (A ≈ 0.25–0.44), reflecting highly heritable moment-to-moment neural flexibility within temporal, cingulo-opercular, and executive networks. Using k-means clustering, we identified two recurring dynamic brain states. State 2 was dominant (occupancy 75.6%) and stable (mean dwell ≈ 3.98 windows), whereas State 1 was transient (occupancy 24.4%, dwell ≈ 1.29 windows). Notably, neither state occupancy nor switching dynamics showed significant heritability, indicating these temporal characteristics are largely driven by environmental or task-related variability. Collectively, these findings reveal a gradient of genetic influence: static connectivity captures a moderately heritable trait-like baseline; mean dynamic connectivity reflects intermediate task-modulated coordination; and dynamic variability represents the most genetically influenced phenotype, highlighting neural flexibility and adaptability as heritable traits. These results suggest that variability in dynamic connectivity may serve as a sensitive endophenotype for cognitive and psychiatric traits, emphasizing the importance of temporal network dynamics in capturing genetically mediated individual differences in working memory.
Mechanism of isoleucyl-tRNA synthetase 2 regulating proliferation and apoptosis of cervical cancer cells
Abstract Isoleucyl-tRNA synthetase 2 (IARS2) is a mitochondrial isoleucine-tRNA synthetase of the class I aminoacyl-tRNA synthetase family, and its role in cervical cancer remains poorly defined. Here, we report that IARS2 promotes cervical cancer cell proliferation and survival through regulation of the Rag GTPases and mTORC1. Elevated IARS2 expression was associated with poorer overall survival in patients with cervical cancer. Silencing of IARS2 significantly reduced cell viability and induced apoptosis in cervical cancer cells. Mechanistically, IARS2 inhibited mTOR degradation and sustained activation of the mTOR–eIF4E axis, thereby supporting cell proliferation. The amino acid–binding pocket of IARS2 was essential for these regulatory effects. Moreover, immunoprecipitation assays revealed that IARS2 interacted with Rag GTPases, particularly RagB and RagD. Together, these findings suggest that IARS2 may function as an amino acid sensor within the Rag–mTORC1 complex and highlight IARS2 as a potential therapeutic target in cervical cancer.
Publisher Correction: Engineering modular and orthogonal genetic logic gates for robust digital-like synthetic biology
Double‐Cyclized Dipeptides for Hierarchical Self‐Assembly Into Crystalline Macroscopic Superhelices
ABSTRACT Cyclic peptides have attracted significant attentiondue to their persistent structures and particular biological effects, which are also key building blocks for creating functional chiral materials. Here, we report a double‐cyclized dipeptide structure—a macrocycle embedded with a cyclic dipeptide—and its use in constructing superhelical structures. By further cyclizing modified cyclic diphenylalanine, a macrocyclic arene embedded with a cyclodipeptide was synthesized. Its unique, rigid structure allows to give hierarchical helical structures by bottom‐up assembly process in solution. These superhelical structures are macroscopic, reaching lengths of at centimeter scale. This demonstrates a bottom‐up, multiscale transfer of chirality from the molecular to the macroscopic scale. Moreover, assembly patterns can be precisely controlled by adjusting kinetic conditions such as temperature, concentration, enantiomeric ratio, and solvent, allowing for both rigid and flexible arrangement modalities. The presence of the macrocycle in these superhelices enables the encapsulation of cationic dyes, leading to both ground‐state and excited‐state chirality transfer. This provides a valuable template for designing macroscopic chiroptical materials.
Expression of Concern: Modified Liu estimators in the linear regression model: An application to Tobacco data
Predicting drainage capillary pressure curves in natural porous media by NMR-T2 relaxometry: implications for CO2 storage
Publisher Correction: An OTX2-PAX3 signaling axis regulates Group 3 medulloblastoma cell fate
Zinc‐Complex Orchestrating Pyroptosis for Hypoxia‐Tolerant Photoimmunotherapy
ABSTRACT Photon‐driven pyroptosis represents an advanced and promising modality in anti‐tumor immunotherapy, offering new avenue in combating cancer recurrence and metastasis. Essential metal‐complex shows great potential in photoimmunotherapy, which however hardly generates reactive oxygen species (ROS) to active photoimmunotherapy under light irradiation due to low spin–orbit coupling (SOC) resulting in intersystem crossing (ISC) being blocked. To address this challenge, we innovatively proposed the concept of essential‐metal ion as an electron‐withdrawing group to modulate the donor‐acceptor (D‐A) system, thereby significantly improving ROS generation efficiency. As a proof of concept, we designed and synthesized a series of Zn 2+ ‐complexes through constructing enhanced D‐A systems. Zn 2+ coordination efficiently enhances the ISC by lowering the excited singlet‐triplet energy gap (ΔE S1−T1 ), leading to exceptionally high ROS generation efficiency through Type I mechanisms to overcome hypoxia and the immunosuppression of tumor microenvironment. In these Zn 2+ ‐complexes, Zn‐TPY‐TPA‐DTZ can photodynamically damage lysosomes to trigger pyroptosis, which further induce anti‐tumor immune responses through the promotion of immunogenic cell death (ICD), and ultimately generates a robust anti‐tumor immune response and curbed the proliferation of 4T1 tumors in vivo. This study provides systematic guidance for the rational design of advanced Zn 2+ ‐complexes, propelling advancements in cancer treatment strategies.
Social gaze dynamics in teams: Comparing face-to-face and video meeting settings
Understanding the factors that promote cooperative behavior in teams is essential for organizational success. While the role of verbal communication in fostering cooperation and team cohesion is well established, the impact of nonverbal signals, particularly eye contact and related patterns, known as social gaze dynamics, has been neglected. In this study, we conducted a multiparty eye-tracking experiment, enabling us to explore the relationship between social gaze, cooperation, and team cohesion. In particular, teams of three participants engaged in a two-stage task: a structured pre-play communication stage (1) and a social dilemma game (2). During pre-play communication, eye-tracked participants performed a real-effort task mirroring the ensuing social dilemma. This allowed us to capture social gaze dynamics and assess their relation to subsequent cooperation and team cohesion. Specifically, we compared the emergence and impact of attentional reciprocity between face-to-face and video meeting settings and provided initial evidence that the extent to which direct gaze is reciprocated within teams influences subsequent cooperative behavior. Overall, our findings highlight potential downsides of increasingly shifting team meetings to the virtual space, where the absence of gaze information affects the emergence and impact of social gaze dynamics.