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  • Bootstrap bounds for supersymmetric quantum mechanics ground states

    What the study found

    The study found that a quantum-mechanics bootstrap approach can give rigorous bounds on ground-state data in supersymmetric quantum mechanics (SUSY QM) and in the Marinari-Parisi matrix model, a matrix version conjectured to describe unstable D 0-brane worldvolume physics. In cases with spontaneously broken supersymmetry, the bounds apply to the lowest-energy normalizable eigenstate.

    Why the authors say this matters

    The authors conclude that these bounds provide useful information about systems where exact solutions are difficult to obtain. They also note that the matrix model results include the expected strong-coupling scaling and a lower bound on the scaling coefficient.

    What the researchers tested

    The researchers applied the quantum-mechanics bootstrap using positivity of moment matrices together with Heisenberg, gauge, and zero-temperature thermal constraints. They studied N = 1 SUSY QM with a cubic superpotential and the supersymmetric matrix quantum mechanics model at large N, using a 44 × 44 bootstrap matrix.

    What worked and what didn't

    For N = 1 SUSY QM with a cubic superpotential, the bounds were tight and agreed well with available approximation methods. At weak coupling, they matched the semiclassical instanton contribution to the supersymmetry-breaking ground-state energy, and at strong coupling they showed the expected scaling and agreed well with Hamiltonian truncation. For the matrix model, they obtained the expected E ~ κg 2/3 scaling at strong coupling and a lower bound κ > .196; at small coupling, they found a spurious kink at g = √2 g_c, which they attribute to truncation error and solver limitations.

    What to keep in mind

    The abstract notes that the small-coupling kink is likely spurious and attributes it to truncation error and solver limitations. It also says possible improvements are discussed, but those details are not included in the available summary.

    • The study applies the quantum-mechanics bootstrap to SUSY QM and the Marinari-Parisi matrix model.
    • It produces rigorous bounds on ground-state data, including cases with spontaneously broken supersymmetry.
    • For N = 1 SUSY QM with a cubic superpotential, the bounds agree well with approximation methods, instanton results, and Hamiltonian truncation.
    • For the matrix model at strong coupling, the authors find the expected E ~ κg 2/3 scaling and a lower bound κ > .196.
    • A kink at g = √2 g_c is described as spurious and attributed to truncation error and solver limitations.
  • Low levels of ESBL E. coli found in rehabilitating howler monkeys

    Low levels of ESBL E. coli found in rehabilitating howler monkeys

    What the study found

    The study found that Escherichia coli was common in fecal samples from rehabilitating Bolivian red howler monkeys, and that most isolates were not extended-spectrum beta-lactamase (ESBL) producers. A small number of isolates showed multidrug resistance (resistance to several antibiotic classes).

    Why the authors say this matters

    The authors say the findings matter because releasing rehabilitated wildlife can introduce antimicrobial resistance into wild ecosystems. They conclude that surveillance in primate rehabilitation programs is important, using a One Health approach, to help prevent potential spread during wildlife release.

    What the researchers tested

    The researchers examined 44 Bolivian red howler monkeys at a rescue center in Madre de Dios, Peru. They collected fecal samples noninvasively, isolated E. coli, tested susceptibility against 12 antibiotics, confirmed ESBL production phenotypically, and calculated multidrug resistance and the multiple antibiotic resistance (MAR) index.

    What worked and what didn't

    E. coli was isolated from 43 of 44 monkeys. Only 1 of 85 isolates was an ESBL producer, and that isolate was multidrug resistant to eight antibiotics across five classes. Among the non-ESBL isolates, resistance was highest to tetracycline, sulfamethoxazole-trimethoprim, and chloramphenicol; five isolates were multidrug resistant, and seven had a MAR index of 0.2 or higher.

    What to keep in mind

    The abstract does not describe follow-up after release, so it does not show whether resistant bacteria spread into wild populations. The findings are limited to one rescue center, one monkey species, and the isolates sampled in this study.

    • E. coli was found in 43 of 44 rehabilitating Bolivian red howler monkeys.
    • Only 1 of 85 E. coli isolates was an ESBL producer.
    • That ESBL-producing isolate was multidrug resistant to eight antibiotics across five classes.
    • Non-ESBL isolates showed the highest resistance to tetracycline, sulfamethoxazole-trimethoprim, and chloramphenicol.
    • Five isolates were multidrug resistant, and seven had a MAR index of at least 0.2.
  • Marketing should be understood as a phenomenon

    Marketing should be understood as a phenomenon

    What the study found

    The article argues that marketing has become too focused on tactical activities and lacks a clear purpose. It proposes shifting from an activity-based view of marketing to a higher-level view of marketing as a phenomenon, meaning its inner meaning and purpose are the main focus.

    Why the authors say this matters

    The authors suggest that understanding marketing as a phenomenon could make the discipline more inclusive. They conclude that this may help different institutions embrace marketing and may help reconcile conflicts between marketing’s stakeholders and between commercial and environmental interests.

    What the researchers tested

    This is a conceptual research article, not an empirical study. The author examines the debate in marketing journals and develops an argument for a transformative approach to how marketing is understood.

    What worked and what didn't

    The article says the current management approach has led marketing to become myopically focused on activities without a clear purpose. It presents the phenomenon-based approach as the alternative and says that, once marketing’s purpose is established, decisions and activities should be considered in light of that purpose.

    What to keep in mind

    The abstract does not describe empirical data, tests, or specific case studies. It also does not provide detailed evidence for the claims beyond the conceptual argument presented in the article.

    • The article argues that marketing has become overly tactical and lacks a clear purpose.
    • It proposes viewing marketing as a phenomenon rather than only as a set of activities.
    • The authors suggest this broader view could make marketing more inclusive.
    • The study says this approach may help reconcile conflicts among stakeholders and between commercial and environmental interests.
    • No empirical study details are described in the abstract.

  • Unbounded domains can admit spectral minimal partitions

    What the study found

    The paper finds that spectral minimal partitions can be studied in unbounded domains, including domains of infinite volume. Existence and the presence of ground states depend on the energy level relative to a threshold involving the essential spectrum of the Schrödinger operator and on whether the partition energy uses a finite p-norm or p = infinity.

    Why the authors say this matters

    The authors present these results as extending the theory of k-spectral minimal partitions to a setting where the domains are unbounded. They also note that new phenomena appear in this setting, including cases where minimizing partitions exist without ground states and where minimal partitions need not be equipartitions at the threshold level.

    What the researchers tested

    The researchers studied k-spectral minimal partitions of domains in d dimensions, where the energy to minimize is a p-norm, with 1 \u2264 p \u2264 \u221e, of the lowest spectral value of a suitable Schr\u00f6dinger operator with Dirichlet boundary conditions on each cell. They proved an upper bound, developed a concentration-compactness-type argument below a threshold, and constructed examples of domains and potentials.

    What worked and what didn't

    Below the threshold, optimal partitions exist and each cell admits ground states, meaning the infimum of the spectrum on each cell is a simple isolated eigenvalue. At the threshold, the paper shows that for p < infinity minimizing partitions may or may not exist, and even when they do, they may not have ground states; for p = infinity, minimal partitions always exist, but they may or may not admit ground states.

    What to keep in mind

    The abstract does not give details of the specific examples beyond saying that they illustrate the new phenomena. It also does not provide numerical results or a single universal existence statement, because the conclusions vary with p, the threshold level, and the domain and potential.

    • The study extends spectral minimal partitions to unbounded domains, including infinite-volume domains.
    • A sharp upper bound is proved using a threshold that involves the essential spectrum and the k-1 partition energy.
    • Below the threshold, optimal partitions exist and each cell has a ground state.
    • At the threshold, p < infinity and p = infinity behave differently: existence and ground states are not guaranteed in the same way.
    • For p = infinity, minimal partitions always exist, but they may fail to be equipartitions at the threshold.

  • AgentBound secures MCP server execution boundaries

    What the study found

    The study found that AgentBound, an access control framework for Model Context Protocol (MCP) servers, can contain malicious behavior without requiring server modifications. The authors report that it can automatically generate access control policies from source code and enforce them with negligible overhead.

    Why the authors say this matters

    The authors conclude that AgentBound provides developers and project managers with a foundation for securing MCP servers while maintaining productivity. They also say it offers a basis for researchers and tool builders to explore declarative access control and MCP security.

    What the researchers tested

    The researchers introduced AgentBound, which combines a declarative policy mechanism inspired by the Android permission model with a policy enforcement engine. They built a dataset of the 296 most popular MCP servers and tested automatic policy generation from source code, threat blocking in several malicious MCP servers, and runtime overhead.

    What worked and what didn't

    The study reports that access control policies could be generated automatically from source code with 80.9% accuracy. It also reports that AgentBound blocked the majority of security threats in several malicious MCP servers and that the enforcement engine introduced negligible overhead.

    What to keep in mind

    The abstract does not provide detailed limitations beyond the tested dataset of 296 popular MCP servers and several malicious MCP servers. The summary available here does not describe which specific threats were blocked or where the policy generation was less accurate.

    • AgentBound is presented as the first access control framework for MCP servers.
    • It uses a declarative policy mechanism inspired by the Android permission model.
    • Automatic policy generation from source code reached 80.9% accuracy on the reported dataset.
    • The framework blocked the majority of threats in several malicious MCP servers.
    • The enforcement engine was reported to add negligible overhead.

  • Fiber-optic probe enabled tumor photothermal therapy with real-time feedback

    What the study found

    The study reports a single-fiber, multifunctional theranostic probe for closed-loop tumor photothermal therapy. It combines a pH indicator, a temperature indicator, and a photothermal agent on a tapered optical fiber so the probe can identify tumor edges, deliver heat-based treatment, and monitor treatment response.

    Why the authors say this matters

    The authors say this matters because optical fiber plus phototheranostic agents may help address limited light penetration depth and the systemic toxicity of nanomaterials. They also state that modular wavelength assignment could support customizable minimally invasive interventions and feedback monitoring.

    What the researchers tested

    The researchers proposed a single-fiber integration scheme using wavelength division multiplexing, a method that separates signals by light wavelength. As a proof of concept, they co-immobilized a pH indicator, a temperature indicator, and a photothermal agent with non-overlapped excitation bands onto the surface of a tapered optical fiber.

    What worked and what didn't

    According to the abstract, the probe could identify tumor edges before treatment by revealing the tumor pH gradient. During treatment, the photothermal agent converted optical energy into heat while temperature monitoring allowed thermal dose control, and after treatment the probe tracked reversal of the acidic tumor microenvironment for rapid efficacy assessment. Animal experiments validated therapeutic efficacy and biocompatibility, and no specific failures are described in the abstract.

    What to keep in mind

    This summary is based on the abstract, so detailed experimental conditions, quantitative results, and comparison with other approaches are not provided. The abstract describes a proof-of-concept study in animals, so the scope of the findings is limited to that setting.

    • The study describes a single-fiber theranostic probe for closed-loop tumor photothermal therapy.
    • The probe combines pH sensing, temperature sensing, and a photothermal agent on a tapered optical fiber.
    • Before treatment, it can identify tumor edges by showing the tumor pH gradient.
    • During treatment, it converts optical energy into heat and monitors temperature for thermal dose control.
    • After treatment, it can monitor reversal of the acidic tumor microenvironment to assess efficacy.
    • Animal experiments reportedly validated the probe's therapeutic efficacy and biocompatibility.

  • Hermite process distributions are shown to have densities

    What the study found

    The study found that, for any distinct times, the vector formed by a Hermite process has a density with respect to Lebesgue measure. In other words, its finite-dimensional distributions are absolutely continuous.

    Why the authors say this matters

    The authors note that the non-Gaussian case had not yet been settled, unlike the Gaussian case of fractional Brownian motion. They also say their methodology could extend to other non-Gaussian models.

    What the researchers tested

    The researchers studied Hermite processes of order q ≥ 1 with self-similarity parameter H in (1/2, 1). They extended a three-step approach from the Gaussian setting using Malliavin calculus, including a determinant identity for the Malliavin matrix, strong local nondeterminism at the level of Malliavin derivatives, and the Bouleau-Hirsch criterion.

    What worked and what didn't

    The approach worked in the sense that it led to the density result for the vector of values at distinct times. The abstract does not describe any failed steps or negative results.

    What to keep in mind

    The summary only states results for finite-dimensional distributions at distinct times, not for other properties of Hermite processes. Limitations beyond this scope are not described in the available abstract.

    • Hermite processes of order q ≥ 1 were shown to have finite-dimensional densities.
    • The result applies for self-similarity parameter H in (1/2, 1).
    • The proof uses Malliavin calculus and a three-step strategy adapted from the Gaussian case.
    • The abstract says the non-Gaussian case had not yet been settled before this work.
    • The authors suggest the method may extend to other non-Gaussian models.

  • Thorium imido complex shows broad small-molecule reactivity

    What the study found

    The study reports a terminal thorium imido metallocene, (η5-C5Me5)2Th(═Ndipp)(dmap), and describes its broad reactivity with small molecules. The complex can activate or react with a range of compounds, including sulfur, alkynes, carbodiimides, aldehydes, carbon disulfide, nitriles, isonitriles, and azides.

    Why the authors say this matters

    The authors conclude that comparing this compound with related terminal imido thorium metallocene derivatives shows how changes in cyclopentadienyl and imido substituents influence reactivity. The study suggests this comparison helps clarify how ligand choice affects the behavior of these thorium compounds.

    What the researchers tested

    The researchers prepared the thorium dimethyl metallocene (η5-C5Me5)2ThMe2 with dippNH2 in toluene in the presence of 4-dimethylaminopyridine to form the terminal thorium imido metallocene, with methane released. They then tested its reactions with many small molecules, including S8, alkynes, carbodiimides, aldehydes, CS2, nitriles, isonitriles, organic azides, Me3PO, thiazole, 2-MepyNO, amines, hydrazine derivatives, terminal alkynes, ketones, amidates, imines, hydrosilanes, and reagents such as Me3SiX, Ph3CN3, CuBr, and AgI.

    What worked and what didn't

    Complex 4 was reported to activate S8, alkynes, carbodiimides, aldehydes, CS2, organic nitriles and isonitriles, and organic azides, giving metallaheterocycle, pyridyl amido, oxido, and bis-amido complexes, respectively. It also formed an adduct with Me3PO, could promote deprotonation in several reactions, behaved as a nucleophile toward PhSiH2Cl, underwent Friedel–Crafts type reactions with Me3SiX and Ph3CN3, and gave distinct products with CuBr and AgI.

    What to keep in mind

    The abstract does not provide quantitative yields, reaction conditions for each transformation, or detailed mechanistic analysis. The summary is limited to the reactions and comparisons stated in the abstract.

    • A terminal thorium imido metallocene, (η5-C5Me5)2Th(═Ndipp)(dmap), was prepared from a thorium dimethyl precursor.
    • The complex reacted with a wide range of small molecules, including sulfur, carbon disulfide, nitriles, and azides.
    • Different reactions produced metallaheterocycle, pyridyl amido, oxido, and bis-amido complexes.
    • The imido moiety also promoted deprotonation reactions and acted as a nucleophile toward PhSiH2Cl.
    • Comparisons with related compounds showed that cyclopentadienyl and imido substituents affect reactivity.

  • Updated pediatric liver size ranges are slightly higher than prior reports

    What the study found

    The study found updated ultrasound reference ranges for normal pediatric liver size. These ranges were based on age and height, and the authors report that normal liver size appears slightly higher than in earlier reports.

    Why the authors say this matters

    The authors state that pediatric liver size is an important part of abdominal imaging because it reflects normal liver growth and possible disease. They conclude that updated reference ranges and nomograms may support more contemporary assessments of normal liver size.

    What the researchers tested

    The researchers reviewed radiology reports from January 2014 to December 2024 for patients under 18 years old with a normal abdominal ultrasound impression. They excluded patients with liver disease or abnormal aspartate aminotransferase (AST) and alanine aminotransferase (ALT) results, then used generalized additive models for location, scale, and shape (GAMLSS) with the Box-Cox power exponential distribution to build reference ranges.

    What worked and what didn't

    A total of 4,611 abdominal ultrasound examinations met the study criteria, including 2,055 males and 2,556 females. Liver size ranged from 4.9 to 5.5 cm at birth and increased with age to 17.2 cm in adolescents aged 17-18 years; in the subset with height data, liver size showed a more linear increase with height and reached 17.5 cm at 180 cm.

    What to keep in mind

    This was a retrospective study from one institution, based on ultrasound reports labeled normal. The abstract does not describe other limitations beyond the inclusion and exclusion criteria used for the reference population.

    • The study created updated pediatric liver size reference ranges using ultrasound.
    • Age-based liver size increased from 4.9-5.5 cm at birth to 17.2 cm at ages 17-18 years.
    • Height-based modeling showed a more linear relationship between liver size and height.
    • The reference ranges were based on 4,611 ultrasound examinations from patients under 18 years old.
    • The authors report normal liver size may be slightly higher than previously reported.

  • TRAVELER benchmark reveals weaker LLM temporal reasoning with vague references

    What the study found

    The study found that TRAVELER is a benchmark for testing temporal reasoning, meaning the ability to interpret time-related references such as explicit dates, implicit references like "yesterday," and vague references like "recently." When evaluated on this benchmark, the large language models tested did well on small event sets and explicit references, but their performance dropped as event sets grew and references became less explicit.

    Why the authors say this matters

    The authors conclude that TRAVELER helps expose limitations in current large language models' event-temporal reasoning capabilities. They also say the publicly available benchmark can be used to test other models beyond those evaluated in the study.

    What the researchers tested

    The researchers introduced TRAVELER, a synthetic question-answering benchmark built from past events in a household domain. It contains 3,300 English questions generated automatically with four templates from event sets containing 5 to 100 events, and it includes explicit, implicit, and vague temporal references.

    What worked and what didn't

    The benchmarked large language models could answer questions over event sets with only a handful of events and with explicit temporal references successfully. Performance clearly deteriorated with larger event sets and when temporal references were less explicit, and the vague question category showed the lowest performance across all models.

    What to keep in mind

    The benchmark uses synthetic questions from a household domain, so the reported results are tied to that setup. For vague references, ground-truth answers were established through human surveys on Prolific, and the abstract does not describe other limitations.

    • TRAVELER is a benchmark for temporal reasoning over explicit, implicit, and vague time references.
    • It includes 3,300 English questions generated from event sets with 5 to 100 events.
    • Four tested large language models performed well on small event sets and explicit references.
    • Performance dropped as event sets got larger and temporal references became less explicit.
    • Vague temporal questions had the lowest performance across all models.