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Building mentally healthy cities with neuroscience

Satellite megaconstellations will threaten space-based astronomy

Search for light sterile neutrinos with two neutrino beams at MicroBooNE

Abstract The existence of three distinct neutrino flavours, ν e , ν μ and ν τ , is a central tenet of the Standard Model of particle physics 1,2 . Quantum-mechanical interference can allow a neutrino of one initial flavour to be detected sometime later as a different flavour, a process called neutrino oscillation. Several anomalous observations inconsistent with this three-flavour picture have motivated the hypothesis that an additional neutrino state exists, which does not interact directly with matter, termed as ‘sterile’ neutrino, ν s (refs.  3–9 ). This includes anomalous observations from the Liquid Scintillator Neutrino Detector (LSND) 3 experiment and Mini-Booster Neutrino Experiment (MiniBooNE) 4,5 , consistent with ν μ  →  ν e transitions at a distance inconsistent with the three-neutrino picture. Here we use data obtained from the MicroBooNE liquid-argon time projection chamber 10 in two accelerator neutrino beams to exclude the single light sterile neutrino interpretation of the LSND and MiniBooNE anomalies at the 95% confidence level (CL). Moreover, we rule out a notable portion of the parameter space that could explain the gallium anomaly 6–8 . This is one of the first measurements to use two accelerator neutrino beams to break a degeneracy between ν e appearance and disappearance, which would otherwise weaken the sensitivity to the sterile neutrino hypothesis. We find no evidence for either ν μ  →  ν e flavour transitions or ν e disappearance that would indicate non-standard flavour oscillations. Our results indicate that previous anomalous observations consistent with ν μ  →  ν e transitions cannot be explained by introducing a single sterile neutrino state.

Still no sign of hypothetical sterile-neutrino particle

The ‘silent’ brain cells that shape our behaviour, memory and health

Sterile-neutrino search based on 259 days of KATRIN data

Abstract Neutrinos are the most abundant fundamental matter particles in the Universe and play a crucial part in particle physics and cosmology. Neutrino oscillation, discovered about 25 years ago, shows that the three known species mix with each other. Anomalous results from reactor and radioactive-source experiments 1 suggest a possible fourth neutrino state, the sterile neutrino, which does not interact through the weak force. The Karlsruhe Tritium Neutrino (KATRIN) experiment 2 , primarily designed to measure the neutrino mass using tritium β-decay, also searches for sterile neutrinos suggested by these anomalies. A sterile-neutrino signal would appear as a distortion in the β-decay energy spectrum, characterized by a discontinuity in curvature (kink) related to the sterile-neutrino mass. This signature, which depends only on the shape of the spectrum rather than its absolute normalization, offers a robust, complementary approach to reactor experiments. Here we report the analysis of the energy spectrum of 36 million tritium β-decay electrons recorded in 259 measurement days within the last 40 eV below the endpoint. The results exclude a substantial part of the parameter space suggested by the gallium anomaly and challenge the Neutrino-4 claim. Together with other neutrino-disappearance experiments, KATRIN probes sterile-to-active mass splittings from a fraction of an eV 2 to several hundred eV 2 , excluding light sterile neutrinos with mixing angles above a few per cent.

Growing cities face mounting challenges

Even in space, telescopes can’t escape photobombers

Determination of the spin and parity of all-charm tetraquarks

Abstract The traditional quark model 1,2 accounts for the existence of baryons, such as protons and neutrons, which consist of three quarks, as well as mesons, composed of a quark–antiquark pair. Only recently has substantial evidence started to accumulate for exotic states composed of four or five quarks and antiquarks 3 . The exact nature of their internal structure remains uncertain 4–29 . Here we report the first measurement of quantum numbers of the recently discovered family of three all-charm tetraquarks 30–32 , using data collected by the CMS experiment at the Large Hadron Collider from 2016 to 2018 (refs.  33,34 ). The angular analysis techniques developed for the discovery and characterization of the Higgs boson 35–37 have been applied to the new exotic states. Here we show that the quantum numbers for parity P and charge conjugation C symmetries are found to be +1. The spin J of these exotic states is determined to be consistent with 2 ħ , while 0 ħ and 1 ħ are excluded at 95% and 99% confidence levels, respectively. The J P C  = 2 ++ assignment implies particular configurations of constituent spins and orbital angular momenta, which constrain the possible internal structure of these tetraquarks.

AI reviewers are here — we are not ready

Data drive city transportation forwards

Integration of hunger and hormonal state gates infant-directed aggression

Abstract Social behaviour is substantially shaped by internal physiological states. Although progress has been made in understanding how individual states such as hunger, stress or arousal modulate behaviour 1–9 , animals experience multiple states at any given time 10 . The neural mechanisms that integrate such orthogonal states—and how this integration affects behaviour—remain poorly understood. Here we report how hunger and oestrous state converge on neurons in the medial preoptic area (MPOA) to shape infant-directed behaviour. We find that hunger promotes pup-directed aggression in normally non-aggressive virgin female mice. This behavioural switch occurs through the inhibition of MPOA neurons, driven by the release of neuropeptide Y from Agouti-related peptide-expressing neurons in the arcuate nucleus (Arc AgRP neurons). The propensity for hunger-induced aggression is set by reproductive state, with MPOA neurons detecting changes in the progesterone to oestradiol ratio across the oestrous cycle. Hunger and oestrous state converge on hyperpolarization-activated cyclic nucleotide-gated (HCN) channels, which sets the baseline activity and excitability of MPOA neurons. Using microendoscopy imaging, we confirm these findings in vivo, revealing that MPOA neurons encode a state for pup-directed aggression. This work provides a mechanistic understanding of how multiple physiological states are integrated to flexibly control social behaviour.

Enteropathogenic bacteria evade ROCK-driven epithelial cell extrusion

Correction: Barriers and facilitators to conducting human subjects research at a safety net institution from the perspective of researchers

Temporal shifts in prognostic factors for 90- and 180-day outcomes after stroke thrombolysis: A machine learning analysis

Introduction Prognostication at 90 and 180 days after thrombolysis for acute ischemic stroke (AIS) is critical, yet the temporal evolution of key predictors remains inadequately understood. The utility of machine learning for systematically comparing prognostic factors across these distinct time points remains to be fully established. Method We retrospectively analyzed consecutive AIS patients undergoing intravenous thrombolysis from October 2020 to December 2024. Features were selected from pre-therapy baseline data via univariable analysis and LASSO regression to develop five machine learning models. Model performance and clinical utility were assessed by AUC-ROC and Decision Curve Analysis (DCA), respectively. The primary endpoint was a modified Rankin Scale > 2 at 90 and 180 days. Results A total of 432 patients were included. At 90 days, 81 patients (18.8%) had an unfavorable outcome. By the 180-day follow-up, 86 patients (19.9%) were lost to follow-up. Among the remaining 346 patients, 48 (13.9%) had an unfavorable outcome. On the holdout test set, Logistic Regression (AUC = 0.757) and Random Forest (AUC = 0.833) were the optimal models for 90- and 180-day outcomes, respectively. While baseline NIHSS score and age were dominant predictors for both endpoints, a notable temporal shift in biomarker significance emerged: admission fibrinogen was a key predictor at 90 days, but was supplanted by white blood cell count for the 180-day prognosis. Conclusion Our study reveals a crucial temporal evolution in prognostic biomarkers after thrombolysis, shifting from fibrinogen at 90 days to white blood cell count at 180 days. This dynamic landscape of predictors, identified through machine learning, underscores the necessity of developing time-specific models to accurately forecast patient recovery.

Fast-track pathway for giant cell arteritis: Improved visual outcomes and reduced healthcare costs

Background Giant cell arteritis (GCA) is the leading vasculitis threatening vision in adults aged ≥ 50 years; permanent vision loss may occur within the first few days after symptom onset. We assessed the impact of a fast-track pathway (FTP) for early diagnosis and treatment of giant cell arteritis in terms of hospitalization patterns and cost-effectiveness. Methods We conducted a retrospective, single-center medico-economic study of consecutive patients referred to a neuro-ophthalmology tertiary center between Nov 1, 2016, and Dec 31, 2022. GCA was defined by ≥ 3 American College of Rheumatology criteria plus a positive temporal-artery biopsy or vascular imaging. An FTP—24/7 access to internal medicine specialists, priority magnetic-resonance imaging, and protocol-driven corticosteroid initiation—was launched on Nov 1, 2018. Demographic, clinical, biological, care-pathway, and cost data were compared before (pre-FTP) and after (post-FTP) implementation. Continuous variables were analyzed with two-sample t tests or Wilcoxon rank–sum tests; categorical variables with χ² or Fisher’s exact test. Findings We included 135 patients (mean age 76 ± 8 years, 61% women): 23 pre-FTP and 112 post-FTP. Baseline characteristics were similar between groups. Compared with the pre-FTP period, the FTP reduced full hospitalizations (62% [69/112] vs 96% [22/23]; p < 0.01) and increased day-hospital or outpatient management (39% vs 4%; p < 0.01). More patients received treatment within one month of symptom onset (54% vs 22%; p < 0.01). Final visual acuity improved (median 2.0 vs 2.6 logMAR; p < 0.01), while cumulative intravenous corticosteroid exposure was significantly reduced (1679 ± 760 mg vs 2295 ± 1055 mg; p = 0.02). Reliance on temporal-artery biopsy fell (17% vs 91%; p < 0.01), owing to a four-fold rise in diagnostic MRI use. Mean total medical costs decreased by €814 per patient (€3672 ± 2861 vs €4486 ± 3193), although this difference did not reach statistical significance (p = 0.23). Interpretation A dedicated fast-track pathway for suspected GCA enables prompt, largely ambulatory care, halves unnecessary full hospitalizations, speeds treatment initiation, improves visual prognosis, and lowers overall expenditure. These findings support wider adoption of imaging-driven FTPs to mitigate the growing clinical and economic burden of GCA.

Cities aren’t built for women — it’s time to change that

Numerical simulation study of gas-solid two-phase flow characteristics in borehole sampling of coal cuttings

During the process of coal sampling through drilling and determining the gas content, the movement characteristics of coal particles within the borehole will affect the exposure time of the collected coal samples. Therefore, studying the movement characteristics of coal particles within the borehole is of great significance. This study employs CFD-DEM to simulate the transport dynamics of Rosin-Rammler distributed coal cuttings during pneumatic sampling, quantifying the effects of drill rod rotation (0–200 rpm) and particle size. Key findings reveal: (1) Axial migration velocity increases significantly with rotational speed, with 0.5–1 mm fine particles accelerating by 39% to 3.9 m s -1 at 100 rpm compared to static condition, though an optimal threshold exists at 150 rpm; (2) Rod rotation induces vortical flow fields, where bit geometry impedes coarse particles (>1 mm) in blade zones, while 0.5–1 mm particles migrate at velocities higher than 2–3 mm fractions under different rotational speeds; (3) Mass flow rate at the orifice doubles with speed (reaching 0.06 kg s -1 at 200 rpm), while static condition reduces efficiency by 50%. The observed significant velocity differentiation depending on particle size implies that using narrowly graded samples (e.g., obtained with adjacent sieve sizes such as 3–4 mm) could potentially improve the accuracy of lost gas content estimation by minimizing variations in particle transport history.

Urban Indian healthcare referral system: A qualitative exploration from the physicians’ perspectives

Background The Indian healthcare system continues to remain unstructured leading to sub-optimal health outcomes, not just in rural but even in urban areas. While physicians play a crucial role in shaping treatment trajectories and managing the referral process, their perspective on the referral system has received very limited academic attention in India. This study attempts to understand the archetypical physician’s referral mechanism and the factors influencing their referral practices. This study also highlights the challenges and possible solutions in operationalising an efficient referral process as suggested by the professionals. Methods In-depth qualitative interviews were conducted with sixty-two physicians consisting of both general physicians and specialists from 19 different disciplines, associated with public and private hospitals in Bengaluru, India. The data, thus collected, was subjected to thematic analysis to generate relevant themes. Results Five themes emerged from the thematic analysis from a phenomenological perspective based on the physicians’ lived experience. First of all, specialist physicians’ availability, accessibility, experience, and reputation strongly influenced referral recommendations. It was also observed that due to lack of a comprehensive healthcare provider database, personal connections and professional networks are utilised. Moreover, although physicians prioritize patients’ affordability and accessibility factors, referral counselling and caregiver-patient communication remained inadequate and required formalization. While the fourth theme clusters around several barriers related to communication, system inefficiencies, lack of awareness, accessibility and affordability among patients; the final theme suggests that the physicians emphasized on urgent need for clear guidelines, regulations and policies to streamline and monitor the referral system. Conclusion This research highlights that physicians recognize the systemic gaps leading to unsolicited health outcomes; yet they are helpless in most cases. The participants emphasized that robust information systems connecting all relevant stakeholders are essential. The exploration reveals that the system will not adopt a structured referral method without the government taking interest in it.

How cities can keep their cool