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A central puzzle in strongly correlated electronic phases is strange metallic transport, marked by T-linear resistivity and B-linear magnetoresistance, in sharp contrast with quadratic scalings observed in conventional metals. Here, we demonstrate that proximity to quantum critical points, a recurring motif in the phase diagrams of strange metal candidates, can explain both transport anomalies. We construct and solve a minimal microscopic model by coupling electronic excitations at the Fermi surface to quantum critical bosons via a spatially disordered Yukawa interaction, as well as static pinned domains of density wave order. The resultant transport relaxation rate scales as k_{B}T/ℏ at low magnetic fields, and as an effective Bohr magneton μ[over ˜]_{B}B/ℏ at low temperatures. Further, the magnetoresistance in our model shows a scaling collapse upon rescaling the magnetic field and the resistance by temperature, in agreement with experimental observations.
This study examined the influence of infant-mother attachment security on the regulation of the hypothalamic-pituitary-adrenal (HPA) axis and cortisol stress responses in 14-month-old infants. Eighty-two mother-infant dyads participated in the Strange Situation Procedure (SSP), with salivary cortisol sampled across four time points. Infant attachment security, maternal depressive symptoms, and infant temperament were assessed longitudinally over the first postnatal year. Infant cortisol trajectories differed by attachment security: insecurely attached infants had significantly higher baseline cortisol, which declined following the SSP, whereas securely attached infants had lower baseline cortisol and a trend toward increased cortisol post-stressor. Maternal cortisol declined over time for all groups, with no differences between mothers of secure and insecure infants. Mothers of securely attached infants experienced sub-clinical depressive symptoms at 32 weeks pre-partum, with a decline of symptoms to a normal range during the first year postpartum. Negative infant temperament increased over the first year but was not associated with attachment security or cortisol response. These findings demonstrate that infant-mother attachment quality shapes infant HPA axis regulation independent of maternal depressive symptoms or negative infant temperament, suggesting the importance of early identification and intervention for attachment difficulties to promote adaptive stress physiology in infants.
The brain combines short- and long-term memory to process, store, and recall multiple different pieces of information. Inspired by this and recent results on multifunctional and parameter-aware learning, we extend a new machine learning technique that combines short- and long-term memory units, specifically, a system consisting of a next-generation reservoir computer (NGRC) and extremely randomized trees (ERT), to process, store, and recall multiple different strange attractors. We train the combined NGRC+ERT system using a two-shot learning approach which significantly improves performance by filtering out unnecessary features, thereby avoiding extensive hyperparameter optimization. We first show that an NGRC+ERT system achieves highly accurate reconstruction of the short- and long-term dynamics of both the Lorenz and Halvorsen chaotic attractors when using an exponential filtering scheme. We validate these findings by training the NGRC+ERT system to reconstruct 16 different attractors and show that sufficient index-based separation in feature space suppresses unwanted switching dynamics, thus stabilizing long-term memory recall. Finally, we identify that defects in short-term memory processing can provoke failure modes in long-term memory recall resulting in confabulation.
Attention-Deficit/Hyperactivity Disorder (ADHD) has gained increasing visibility in public discourse on mental health, particularly in adulthood, while remaining associated with stigma, oversimplification, and misinformation. The present study aimed to identify mental representations of ADHD among Brazilian adults with and without a diagnosis. This qualitative, exploratory, cross-sectional study included a non-probabilistic sample of 805 adults, comprising 463 participants with ADHD and 342 without a diagnosis. Data were collected online using the Free Word Association Technique, based on the inductive stimulus "ADHD." Analyses were conducted using IRaMuTeQ software, including word cloud analysis, Descending Hierarchical Classification, and specificity analyses, complemented by thematic content analysis. Results were primarily organized into four classes: (a) Stigma and delegitimization of ADHD, characterized by pejorative labels and simplified understandings of the condition; (b) Distress and Insecurity, reflected in feelings of insecurity, frustration, and low self-esteem; (c) Technical-Diagnostic Perspective on ADHD, centered on symptoms such as inattention, deficits, and hyperactivity; and (d) Dysfunctional behaviors, related to difficulties with organization, procrastination, and overload. Overall, more similarities than differences were observed in how participants with and without ADHD represented the disorder. These findings suggest that ADHD is socially constructed as an experience that extends beyond its clinical definition, shaped by symbolic, normative, and affective processes. Accordingly, there is a need for clinical and psychoeducational practices that integrate diagnostic knowledge with subjective experiences and the sociocultural conditions that influence distress and daily functioning in the Brazilian context.
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Futrell and Mahowald frame the success of neural language models (LMs) as supporting gradient, usage-based linguistic theories. I argue that LMs can also instantiate theories based on formal structures - the types of theories seen in the generative tradition. This argument expands the space of theories that can be tested with LMs, potentially enabling reconciliations between usage-based and generative accounts.
Momentum-resolved electron energy-loss spectroscopy (EELS) on strange-metal BiSrCaCuO(Bi-2212) observes a broad charge continuum that is nearly momentum independent over an extended finite-momentum regime, whereas optical spectroscopy determines a metallic local conductivity. We analyze the long-wavelength response function that connects these regimes: the proper homogeneous bulk charge-density polarization. For any homogeneous-conserving metal whose longitudinal matter conductivity remains finite in thelimit at fixed nonzero frequency, the Ward identity gives. We then prove that any nonnegative normalized momentum-resolution kernel with a self-similar-scaled profile, uniformly bounded second moment, and tight second-moment tails preserves thisasymptotic behavior, changing only the prefactor. Consequently, a nearly local finite-continuum in Bi-2212, if continuously connected to a regular metallic optical limit of the same proper bulk response, is naturally described by a crossover surface. The theorem is a constraint on the proper bulk density response, or on a positive-scaled convolution of it; screened loss functions and surface EELS observables require the corresponding electrodynamic conversion before the constraint is applied.
A microsporidium was found in a single larva of the nine-spotted moth Amata phegea (Lepidoptera: Erebidae) in Central Bulgaria. Multiple mature spores, occupying inner tissues of the host, suggest infection rather than environmental contamination. This specimen was primarily processed for light microscopy and for sequencing of the small subunit ribosomal (SSU) region of rDNA. There were multiple ovoid spores, measuring 2.9 × 1.8 μm. The rDNA sequence (GenBank accession number PP003326) showed 99.3% similarity and a genetic distance of 0.006 to Globulispora mitoporans (#KT762153). This microsporidium, belonging to the Enterospora-like clade in the order of Enterocytozoonidae, is a pathogen of the water flea Daphnia pulex (Branchiopoda: Daphniidae). The same level of genetic divergence is observed in different geographical isolates of another species from the same clade - Enterocytospora artemiae. In the absence of tissue samples fixed for transmission electron microscopy, it was still possible to use remnants of infected host tissue from the Giemsa-stained slides for this procedure. The spores possessed a large single nucleus located in the center of the cell, a single layer of polar tube coils, a globose polaroplast, and an undulating layer of the spore wall. The ultrastructural composition of the spore also corresponded to that of Globulispora. The finding adds to our knowledge of ability of particular microsporidian parasites to penetrate hosts from diverse taxa and habitats.
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A 79-year-old woman presents to the hospital with dyspnoea, fever, and hypotension, and is diagnosed with community-acquired pneumonia and septic shock. Resuscitation is initiated with fluids and vasopressors, and a central venous catheter is placed. However, during the procedure, the guide experiences resistance and cannot be removed, becoming trapped. This is confirmed with tomography and reconstruction, demonstrating intravascular position. The patient is then sent to interventional cardiology for extraction, which is successfully performed using the EN Snare (Merit Medical). The significance of this case lies in the complications of not guiding procedures with ultrasound and how to resolve them, such as the guide being trapped in this patient.
Non-Fermi liquid (NFL) behavior and strange metallicity, often marked by resistivity linear in temperature and the breakdown of Fermi liquid quasiparticles, are recurring themes in strongly correlated quantum materials, ranging from high-temperature cuprates to twisted van der Waals heterostructures. Enormous efforts are being made to uncover the origin of NFL underlying strange metallicity, yet progress remains slow. Here, we report appearance of an NFL phase in a discontinuous metal-NFL-insulator transition of the Holstein model away from half-filling. The NFL appears as a distinct ground state of finite regime in addition to the metal and insulator states in a phase diagram, not as a consequence of quantum criticality of a continuous transition. Also, the discontinuity of the metal-NFL transition produces a mixture between the two phases along the phase boundary to exhibit a two-fluid kind strange metallicity. The dynamical mean-field theory was employed with Wilson’s numerical renormalization group in infinite dimensions. We trace the NFL phase to a spin gap opening in the absence of a charge gap. This offers an intriguing route to understanding the NFL and intertwined superconductivity in correlated quantum materials.
We report the first search for the flavor-changing neutral-current decays B→X_{s}νν[over ¯], where X_{s} is a hadronic system with strangeness equal to 1, in data collected with the Belle II detector at the SuperKEKB asymmetric-energy e^{+}e^{-} collider. The data sample corresponds to an integrated luminosity of 365  fb^{-1} collected at the ϒ(4S) resonance and 43  fb^{-1} collected at a center-of-mass energy 60 MeV below resonance for estimation of e^{+}e^{-}→qq[over ¯] continuum background. One of the B mesons from the ϒ(4S)→BB[over ¯] decay is fully reconstructed in a hadronic decay mode. The B→X_{s}νν[over ¯] decay is reconstructed with a sum-of-exclusives approach that uses 30 X_{s} decay modes. This approach provides high sensitivity to the inclusive decay, despite the presence of two undetected neutrinos. The search is performed in three regions of the X_{s} mass, M_{X_{s}}^{true}, chosen to separate contributions from K, K^{*}(892), and heavier strange final states. We do not observe a significant signal and set upper limits at 90% confidence level on the partial branching fractions for the regions 0.0<M_{X_{s}}^{true}<0.6  GeV/c^{2}, 0.6<M_{X_{s}}^{true}<1.0  GeV/c^{2}, and 1.0  GeV/c^{2}<M_{X_{s}}^{true} of 2.2×10^{-5}, 9.3×10^{-5}, and 30.9×10^{-5}, respectively. Combining the three mass regions, we obtain the upper limit on the branching fraction, B(B→X_{s}νν[over ¯])<3.3×10^{-4}.
Initial molecular genetic studies identified specific genes that contribute to variation in associations between maternal sensitivity and infant attachment, but these findings from small samples failed to replicate in larger-sample investigations. A recent study shifted attention to a genetic marker of the opioid system, OPRM1 rs1799971, providing evidence for its role in moderating the association between maternal insensitivity and resistant attachment assessed via the Modified Strange Situation. This preregistered report attempted to replicate these results leveraging data from the NICHD Study of Early Child Care and Youth Development (SECCYD). We also examined robustness to other attachment assessments (i.e. Strange Situation Procedure, Attachment Q-Sort) and more comprehensive assessments of maternal sensitivity utilizing data from the SECCYD and the Generation R Study. The previously reported results did not replicate, providing another replication failure in the candidate gene literature. We discuss avenues forward by highlighting genetically-informed research designs derived from current best practices.
Quantum phase transitions are an established setting for emergent phenomena driven by strong electronic correlations, including strange metals and unconventional superconductivity. These phenomena have been explored extensively in Kondo-lattice materials tuned to an antiferromagnetic quantum critical point (QCP), but superconductivity emerging near ferromagnetic quantum criticality has not yet been observed, and the conditions under which it occurs in proximity to ferromagnetism remain undetermined. Here, we report a new setting for superconductivity in the ferromagnetic Kondo-lattice material Ce[Formula: see text]CoGe[Formula: see text], which has a ferromagnetic ground state at ambient pressure and evolves to antiferromagnetism under applied pressure. The antiferromagnetic transition is suppressed to a zero-temperature QCP, accompanied by strange-metal behavior. Superconductivity does not occur at the QCP, but instead appears at pressures beyond the magnetic instability. These findings suggest that Ce[Formula: see text]CoGe[Formula: see text] represents a distinct class of correlated materials exhibiting a unique scenario for the emergence of superconductivity, likely associated with unconventional pairing mechanisms beyond spin fluctuations.
Ambient-pressure superconductivity in nickelates has been capped at an onset transition temperature (T c onset) of ∼50 K, a value that remains lower than those of the cuprate (∼133 K) and iron-based (∼55 K) counterparts, despite the promise shown under high pressure. Here, we report ambient-pressure superconductivity onset at ∼63 K in epitaxial (La,Pr)3Ni2O7 thin films grown under compressive strain on SrLaAlO4 substrates. This T c leap is enabled by pushing our gigantic-oxidative atomic-layer-by-layer epitaxy (GAE) method into an extreme non-equilibrium growth regime. It simultaneously enhances kinetics via higher temperatures and achieves full oxygenation in situ without post-annealing. Synchrotron X-ray diffraction and scanning transmission electron microscopy confirm that this approach yields films of large-scale crystalline purity, overcoming the inherent metastability of the strained superconducting phase. Transport measurements reveal a zero-resistance temperature (T c zero) reaching ∼37 K, while mutual inductance measurements demonstrate a robust diamagnetic transition starting at ∼23 K. These films exhibit a systematic evolution in their normal-state resistivity-temperature curve: the power-law exponent α evolves from Fermi-liquid-like (α ∼ 2) at lower T c onset to strange-metal-like (α ∼ 1) in higher T c onset samples, directly linking the enhanced superconductivity to non-Fermi liquid behavior. Mapping the vortex melting phase diagram by the mutual inductance technique further reveals the 2D melting limit suppressed to near zero, which demonstrates significantly stronger interlayer coupling than that of cuprates. These results identify the nickelates as ambient-pressure strange-metal high-temperature superconductors with strong interlayer coupling.
This paper intends to go through the medical history of a new syndrome, beginning from its incidental observation to the nowadays ongoing reports quickly approaching 7000 published papers. This large number makes it difficult for the researcher to correctly quote the previous significant published data, and the usual strategy is to copy and paste the last articles references. This review is mainly detailed historical research of the step-by-step journey mainly of the first three decades, with less attention to the ongoing and late scientific controversies that are indeed quoted. The new syndrome was early named "precordial early repolarization (PER) syndrome" but became popular after being renamed "Brugada syndrome" (BS). Nowadays it is classified as one of the "J wave syndromes" (JWSs). The main characteristic of this new entity was an unusual astonishing precordial coved ST segment elevation that gave rise since its first descriptions to two different pathophysiological theories, one organic and the second functional. The first theory ascribed the ST elevation to an unusual pattern of depolarization at the right ventricular outflow tract (RVOT), while the second favored an abnormal dynamic repolarization pattern. Both phenomena were sometimes linked to an ion channel genetic abnormality. In the following decades, many eminent scientists and also some excellent humble cardiologists made significant observations regarding epidemiology, laboratory, diagnostic techniques, genetic, clinical findings, histology, embryology, therapeutic approaches, and risk stratification. This rush "to be the first who" has created more confusion than certainty, and only in this last decade a more scientific and less emotional approach has led to a common acceptance of an underlying organic background that causes a strange conduction delay mainly at the epicardial level of the RVOT. "Next generation" cardiologists are in charge of further elucidating the genetic, the structural, and electrical pathophysiology, and the correct risk stratification needed to correctly identify the true patients who need a therapy and avoid unusual and dangerous treatments to healthy people with a benign strange ECG.