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Volatility is an essential element in the important applications of term structure models. The relative performance of alternative models is closely related to their ability to capture the volatility of changes in the interest rate. Alternative models of the term structure of interest rates are classified in two approaches. These are the no-arbitrage and the general equilibrium approach.

Nuclear magnetic resonance (NMR) experiments on subnanoliter (sub-nL) volumes are hindered by the limited sensitivity of the detector and the difficulties in positioning and holding such small samples in proximity of the detector. In this work, we report on NMR experiments on liquid and biological entities immersed in liquids having volumes down to 100 pL. These measurements are enabled by the fabrication of high spatial resolution 3D printed microfluidic structures, specifically conceived to guide and confine sub-nL samples in the sub-nL most sensitive volume of a single-chip integrated NMR probe. The microfluidic structures are fabricated using a two-photon polymerization 3D printing technique having a resolution better than 1 μm3. The high spatial resolution 3D printing approach adopted here allows to rapidly fabricate complex microfluidic structures tailored to position, hold, and feed biological samples, with a design that maximizes the NMR signals amplitude and minimizes the static magnetic field inhomogeneities. The layer separating the sample from the microcoil, crucial to exploit the volume of maximum sensitivity of the detector, has a thickness of 10 μm. To demonstrate the potential of this approach, we report NMR experiments on sub-nL intact biological entities in liquid media, specifically ova of the tardigrade Richtersius coronifer and sections of Caenorhabditis elegans nematodes. We show a sensitivity of 2.5x1013 spins/Hz1/2 on 1H nuclei at 7 T, sufficient to detect 6 pmol of 1H nuclei of endogenous compounds in active volumes down to 100 pL and in a measurement time of 3 hours. Spectral resolutions of 0.01 ppm in liquid samples and of 0.1 ppm in the investigated biological entities are also demonstrated. The obtained results may indicate a route for NMR studies at the single unit level of important biological entities having sub-nL volumes, such as living microscopic organisms and eggs of several mammalians, humans included. [ABSTRACT FROM AUTHOR]

We review the theory of ponderomotive forces of classical nonionizing electromagnetic (EM) radiation exerted on dispersive matter. Minkowski's EM energy and momentum density lack any dispersion term in contrast to Nelson's theory, where they are included naturally. By considering force experiments on a dielectric mirror immersed in weakly dispersive liquids [ R. V. Jones and B. Leslie Proc. R. Soc. London, Ser. A 360 347 (1978) ], we found that the appearance of the dispersive term should depend on the phase of the mirror reflectivity. It thus matters if the electric or the magnetic field is dominant at the interface. Accordingly, the force measurements depend on the boundary condition and do not permit to uniquely determine the EM momentum in the liquids. Force measurements as a function of the reflectivity phase would permit to experimentally verify the expressions for the EM energy density in a dispersive medium. In our experiments, we chop light beams of different photon energies to excite the motion of a very thin and long Si slab near its mechanical resonance under UHV conditions. This permits to study the force response, where the power reflectivity of the sample varies from 0.7 to smaller than 10-3. The determination of the velocity of the slab with a Doppler interferometer yields the effective force exerted by the light beam. The measurements also confirm our theoretical considerations that the observed forces due to EM radiation cannot be traced to the EM momentum in matter, as the observed forces primarily depend on the boundary conditions. Minkowski's stress tensor remains applicable in our case thanks to the embedding of the Si slab in vacuum. Our quantitative analysis of the experimental data reveals an extra force of thermal origin most likely associated with the difference of the native oxide thickness on the surfaces of the slab. The estimated difference in oxide layer thickness amounts to ~4 nm. [ABSTRACT FROM AUTHOR]

We describe a setup for the x-ray detection of ferromagnetic resonance in the longitudinal geometry using element-specific transmission measurements. Thin magnetic film samples are placed in a static magnetic field collinear with the propagation direction of a polarized soft x-ray beam and driven to ferromagnetic resonance by a continuous wave microwave magnetic field perpendicular to it. The transmitted photon flux is measured both as a function of the x-ray photon energy and as a function of the applied static magnetic field. We report experiments performed on a 15 nm film of doped Permalloy (Ni73Fe18Gd7Co2) at the L3/L2-edges of Fe, Co, and Ni. The achieved ferromagnetic resonance sensitivity is about 0.1 monolayers/Hz. The obtained results are interpreted in the framework of a conductivity tensor based formalism. The factors limiting the sensitivity as well as different approaches for the x-ray detection of ferromagnetic resonance are discussed. [ABSTRACT FROM AUTHOR]

We have realized an innovative integrated detector for electron spin resonance spectroscopy. The microsystem, consisting of an LC oscillator, a mixer, and a frequency division module, is integrated onto a single silicon chip using a conventional complementary metal-oxide-semiconductor technology. The implemented detection method is based on the measurement of the variation of the frequency of the integrated LC oscillator as a function of the applied static magnetic field, caused by the presence of a resonating sample placed over the inductor of the LC-tank circuit. The achieved room temperature spin sensitivity is about 1010 spins/GHz1/2 with a sensitive volume of about (100 μm)3. [ABSTRACT FROM AUTHOR]

Focused electron beam induced depositions of nickel-containing materials obtained by using bis(methylcyclopentadienyl)nickel(II) Ni(C5H4CH3)2 and tetrakis(trifluorophosphine)nickel(0) Ni(PF3)4 as precursors, were compared in terms of chemical composition and electrical resistivity. Ni(PF3)4 decomposed into higher Ni content materials than that obtained with Ni(C5H4CH3)2 (typically 40 and 10 at. %, respectively). Attempts of increasing the Ni content by injecting controlled flows of molecular oxygen or hydrogen simultaneously to the precursor vapors resulted in all cases in the increase of incorporated oxygen only. The lowest electrical resistivities of 150 nm wide lines obtained from Ni(C5H4CH3)2 and Ni(PF3)4 were 1 and 1×10-3 Ω cm, respectively. The electrical resistivity of the latter lines showed an e(-T) dependence with temperature, typical of magnetic heterogeneous alloys and granular alloys containing insulating particles. Transmission electron microscopy investigations of a freestanding rod obtained from Ni(PF3)4 showed a nanocrystalline structure of nickel grains surrounded by a partially amorphous cladding. [ABSTRACT FROM AUTHOR]

A microscopic four-point probe (μ4PP) for resistivity measurements on thin films was designed and fabricated using the negative photoresist SU-8 as base material. The device consists of four microscopic cantilevers, each of them supporting a probe tip at the extremity. The high flexibility of SU-8 ensures a stable electrical point contact between samples and probe tip with all four electrodes even on rough surfaces. With the presented surface micromachining process, μ4PPs with a probe-to-probe spacing of 10–20 μm were fabricated. Resistivity measurements on thin Au, Al, and Pt films were performed successfully. The measured sheet resistances differ by less than 5% from those obtained by a commercial macroscopic resistivity meter. Due to the low contact forces (Fcont<10-4 N), the μ4PP is suitable to be applied also to fragile materials such as conducting polymers. Here the authors demonstrate the possibility of performing resistivity measurements on 100-nm-thick pentacene (C22H14) films with a sheet resistance Rs>106 Ω/□. [ABSTRACT FROM AUTHOR]

We developed an inductive system to measure the surface concentration of superparamagnetic microbeads resulting from a bioassay. Our tabletop apparatus, tested with Dynal MyOne™ microbeads, has a detection limit of about 1000 beads/Hz1/2 (i.e., about 2×1010 Bohr magnetons). The system can measure surface concentrations from 0.01% to 100% over the 6 mm2 sensitive area with an integration time of 1 s. [ABSTRACT FROM AUTHOR]

We describe the fabrication and the performance of a microcoil-based probe for electron spin resonance (ESR) spectroscopy on micrometer sized samples. The probe consists of a 100 μm planar microcoil fabricated on a glass substrate, tuned and matched at 1.4 GHz (L band) using miniaturized ceramic capacitors. We performed continuous wave ESR experiments on samples having a volume between (100 μm)[sup 3] and (10 μm)[sup 3]. At 300 K, we achieved a spin sensitivity of about 10[sup 10] spins/G Hz[sup 1/2], which is comparable to that of commercial ESR spectrometers operating at 9 GHz (X band). The results reported in this article suggest that microcoil-based probes might represent a valid alternative to conventional microwave cavities for ESR studies of sample of the order of (100 μm)[sup 3] and smaller. © 2003 American Institute of Physics. [ABSTRACT FROM AUTHOR]

In this article, we present the first fully integrated nuclear magnetic resonance probe ever realized. Planar spiral coils, a radio-frequency preamplifier, a mixer, and an audio-frequency amplifier are integrated using a standard complementary metal-oxide-semiconductor technology on a single silicon chip of 10 mm[sup 2]. A 1 mm[sup 3] solid sample of cis-polyisoprene, placed over one of the integrated coils, is used as resonating material. The realized integrated probe allows measurements of static magnetic fields from 0.7 to 7 T with a magnetic-field resolution better than 1 ppm/Hz[sup 1/2], an absolute accuracy better than 3 ppm, and a spatial resolution of about 1 mm. © 2001 American Institute of Physics. [ABSTRACT FROM AUTHOR]

We present a method to measure continuous-wave ferromagnetic resonance (FMR) spectra based on the core-level absorption of circularly polarized x rays. The technique is demonstrated by using a monochromatic x-ray beam incident on an yttrium–iron–garnet sample excited by a microwave field at 2.47 GHz. FMR spectra are obtained by monitoring the x-ray absorption intensity at the photon energy corresponding to the maximum of the magnetic circular dichroism effect at the iron L2,3 edges as a function of applied magnetic field. The x-ray FMR signal is shown to be energy dependent, which makes the technique element sensitive and opens up new possibilities to perform element-resolved FMR in magnetic alloys and multilayers. [ABSTRACT FROM AUTHOR]

Hall devices having an active area of about (500 nm)2 are fabricated by focused electron-beam-induced deposition. The deposited material consists of cobalt nanoparticles in a carbonaceous matrix. The realized devices have, at room temperature, a current sensitivity of about 1 V/AT, a resistance of a few kilo-ohms, and can be biased with a maximum current of about 1 mA. The room-temperature magnetic field resolution is about 10 μT/Hz1/2 at frequencies above 1 kHz. [ABSTRACT FROM AUTHOR]

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Women are more likely than men to suffer from anxiety disorders and major depression. These disorders share hyperresponsiveness to stress as an etiological factor. Thus, sex differences in brain arousal systems and their regulation by chronic stress may account for the increased vulnerability to these disorders in women. Social isolation is a model of early life stress that results in neurobiological alterations leading to increased anxiety-like and depressive-like behaviors. Here we investigated the sex difference in the effects of post-weaning social isolation on acute stress sensitivity and behavior in rats. In both sexes, social isolation at weaning reduced basal levels of the neuroactive steroid allopregnanolone in the brain and of corticosterone in plasma. Moreover, acute stress increased plasma corticosterone levels in both group-housed and socially isolated male and female rats; however this effect was greater in male than female rats subjected to social isolation. Intriguingly, group-housed female rats showed no change in plasma and brain levels of allopregnanolone after acute foot-shock stress. The absence of stress-induced effects on allopregnanolone synthesis might be due to the physiologically higher levels of this hormone in females vs. males. Accordingly, increasing allopregnanolone levels in male rats blunted the response to foot-shock stress in these animals. Socially isolated male, but not female, rats also display depressive-like behavior and increased hippocampal brain-derived neurotrophic factor (BDNF). The ovarian steroids could “buffer” the effect of this adverse experience in females on these parameters. Finally, the dexamethasone (DEX) suppression test indicated that the chronic stress associated with social isolation impairs feedback inhibition in both sexes in which an increase in the abundance of glucocorticoid receptors (GRs) in the hippocampus was found. Altogether, these results demonstrate that social isolation affects neuroendocrine reactivity to stress, plasticity and emotionality in a sexually dimorphic manner. [ABSTRACT FROM AUTHOR]

We present direct local-probe evidence for strongly hybridized nuclear-electronic spin states of an Ising ferromagnet LiHoF4 in a transverse magnetic field. The nuclear-electronic states are addressed via a magnetic resonance in the GHz frequency range using coplanar resonators and a vector network analyzer. The magnetic resonance spectrum is successfully traced over the entire field-temperature phase diagram, which is remarkably well reproduced by mean-field calculations. Our method can be directly applied to a broad class of materials containing rare-earth ions for probing the substantially mixed nature of the nuclear and electronic moments. [ABSTRACT FROM AUTHOR]

Background: Mechanical thrombectomy (MT) was found to be beneficial in acute ischemic stroke patients with anterior tandem occlusion (a-TO). Instead, little is known about the effectiveness of MT in stroke patients with posterior tandem occlusion (p-TO). We aimed to compare MT within 24 h from last known well time in ischemic stroke patients with p-TO versus a-TO., Methods: We conducted a cohort study on prospectively collected data of patients registered in the Italian Registry of Endovascular Treatment in Acute Stroke (IRETAS) who were treated with MT within 24 h from last known well time for acute ischemic stroke with p-TO (n = 275) or a-TO (n = 1853)., Results: After adjustment for unbalanced pre-procedure variables (year 2015-2021, age, sex, NIHSS score, ASPECTS, and time strata for puncture groin) and pre-stroke mRS score as pre-defined predictor, p-TO was significantly associated with lower probability of mRS score 0-2 (OR 0.415, 95% CI 0.268-0.644) and with higher risk of death (OR 2.813, 95% CI 2.080-3.805) at 3 months. After adjustment for unbalanced procedural and post-procedure variables (IVT, general anesthesia, TICI 3, and 24-h HT) and pre-stroke mRS score as pre-defined predictor, association between p-TO and lower probability of mRS score 0-2 (OR 0.444, 95% CI 0.304-0.649) and association between p-TO and with higher risk of death (OR 2.971, 95% CI 1.993-4.429) remained significant., Conclusions: MT within 24 h from last known well time in ischemic stroke patients with p-TO versus a-TO was associated with worse outcomes at 3 months., (© 2024. Fondazione Società Italiana di Neurologia.)

Objective: This study was undertaken to assess the effectiveness/tolerability of adjunctive cenobamate, variations in the load of concomitant antiseizure medications (ASMs) and predictors of clinical response in people with focal epilepsy., Methods: This was a retrospective study at 21 centers participating in the Italian Expanded Access Program. Effectiveness outcomes included retention and responder rates (≥50% and 100% reduction in baseline seizure frequency). Tolerability/safety outcomes included the rate of treatment discontinuation due to adverse events (AEs) and their incidence. Total drug load was quantified as the number of concomitant ASMs and total defined daily dose (DDD). Concomitant ASMs were also classified according to their mechanism of action and pharmacokinetic interactions to perform explorative subgroup analyses., Results: A total of 236 subjects with a median age of 38 (Q 1 -Q 3 = 27-49) years were included. At 12 months, cenobamate retention rate was 78.8% and responders were 57.5%. The seizure freedom rates during the preceding 3 months were 9.8%, 12.2%, 16.3%, and 14.0% at 3, 6, 9, and 12 months. A higher percentage of responders was observed among subjects treated with clobazam, although the difference was not statistically significant. A total of 223 AEs were recorded in 133 of 236 participants, leading to cenobamate discontinuation in 8.5% cases. At 12 months, a reduction of one or two concomitant ASMs occurred in 42.6% and 4.3% of the subjects. The median total DDD of all concomitant ASMs decreased from 3.34 (Q 1 -Q 3  = 2.50-4.47) at baseline to 2.50 (Q 1 -Q 3  = 1.67-3.50) at 12 months (p < .001, median percentage reduction = 22.2%). The highest rates of cotreatment withdrawal and reductions in the DDD were observed for sodium channel blockers and γ-aminobutyric acidergic modulators (above all for those linked to pharmacokinetic interactions), and perampanel., Significance: Adjunctive cenobamate was associated with a reduction in seizure frequency and in the burden of concomitant ASMs in adults with difficult-to-treat focal epilepsy. The type of ASM associated did not influence effectiveness except for a favorable trend with clobazam., (© 2024 The Author(s). Epilepsia published by Wiley Periodicals LLC on behalf of International League Against Epilepsy.)

We report on the design and characterization of a single chip integrated pulsed electron spin resonance detector operating at 9.1 GHz. The microsystem consists of an excitation microcoil, a detection microcoil, a low noise microwave preamplifier, a mixer, and an intermediate frequency (IF) amplifier. The chip area is about 0.7 mm 2 . To exemplify its possible applications, we report the results of single pulse, Rabi nutation, Hahn echo, two echoes, Carr-Purcell, and inversion recovery echo experiments performed on 0.02 and 0.05 nL samples of α, γ-bisdiphenylene-β-phenylallyl (BDPA) and 1% BDPA in polystyrene (BDPA:PS) at room temperature. The measured spin sensitivity is about 8 × 10 7 spins/Hz 1/2 on a sensitive volume of about 0.1 nL. The microsystem power consumption is less than 100 mW, the radio frequency (RF) input bandwidth is 8.8 to 9.8 GHz, the IF output bandwidth is DC to 350 MHz, and the deadtime is less than 30 ns.

Field-effect transistors (FETs) based on two-dimensional materials (2DMs) with atomically thin channels have emerged as a promising platform for beyond-silicon electronics. However, low carrier mobility in 2DM transistors driven by phonon scattering remains a critical challenge. To address this issue, we propose the controlled introduction of localized tensile strain as an effective means to inhibit electron-phonon scattering in 2DM. Strain is achieved by conformally adhering the 2DM via van der Waals forces to a dielectric layer previously nanoengineered with a gray-tone topography. Our results show that monolayer MoS 2 FETs under tensile strain achieve an 8-fold increase in on-state current, reaching mobilities of 185 cm²/Vs at room temperature, in good agreement with theoretical calculations. The present work on nanotopographic grayscale surface engineering and the use of high-quality dielectric materials has the potential to find application in the nanofabrication of photonic and nanoelectronic devices., (© 2024. The Author(s).)

Background: We aim to assess the association between procedural time and outcomes in patients in unsuccessful mechanical thrombectomy (MT) for anterior circulation acute stroke., Methods: We conducted a cohort study on prospectively collected data from patients with M1 and/or M2 segment of middle cerebral artery occlusion with a thrombolysis in cerebral infarction 0-1 at the end of procedure. Primary outcome was 90-day poor outcome. Secondary outcomes were early neurological deterioration (END), symptomatic intracranial hemorrhage (sICH) according to ECASS II and sICH according to SITS-MOST., Results: Among 852 patients, after comparing characteristics of favourable and poor outcome groups, logistic regression analysis showed age (OR: 1.04; 95%CI: 1.02-1.05; p < 0.001), previous TIA/stroke (OR: 0.23; 95%CI: 0.12-0.74; p = 0.009), M1 occlusion (OR: 1.69; 95%CI: 1.13-2.50; p = 0.01), baseline NIHSS (OR: 1.01; 95%CI: 1.06-1.13; p < 0.001) and procedural time (OR:1.00; 95% CI: 1.00-1.01; p = 0.003) as independent predictors poor outcome at 90 days. Concerning secondary outcomes, logistic regression analysis showed NIHSS (OR:0.96; 95%CI: 0.93-0.99; p = 0.008), general anaesthesia (OR:2.59; 95%CI: 1.52-4.40; p < 0.001), procedural time (OR: 1.00; 95% CI: 1.00-1.01; p = 0.002) and intraprocedural complications (OR: 1.89; 95%CI: 1.02-3.52; p = 0.04) as independent predictors of END. Bridging therapy (OR:2.93; 95%CI: 1.21-7.09; p = 0.017) was associated with sICH per SITS-MOST criteria whereas M1 occlusion (OR: 0.35; 95%CI: 0.18-0.69; p = 0.002), bridging therapy (OR: 2.02; 95%CI: 1.07-3.82; p = 0.03) and intraprocedural complications (OR: 5.55; 95%CI: 2.72-11.31; p < 0.001) were independently associated with sICH per ECASS II criteria. No significant association was found between the number of MT attempts and analyzed outcomes., Conclusions: Regardless of the number of MT attempts and intraprocedural complications, procedural time was associated with poor outcome and END. We suggest a deeper consideration of procedural time when treating anterior circulation occlusions refractory to MT., (© 2024. Springer-Verlag GmbH Germany, part of Springer Nature.)

Our laboratory has previously shown that chronic ethanol exposure elicits enhanced working memory performance in female, but not male, adult Sprague-Dawley rats, indicative of a fundamental sex difference in cortical plasticity. Recent studies have furthermore revealed that females display markedly reduced HCN-mediated channel activity in inhibitory Martinotti interneurons after chronic ethanol exposure that is similarly not observed in males. From these observations we hypothesized that alcohol induces facilitated working memory performance via down-regulation of these channels' activity specifically within interneurons. To test this hypothesis, we employed a Pol-II compatible shRNA expression system to elicit targeted knockdown of HCN channel activity in these cells, and measured performance on a delayed Non-Match-to-Sample (NMS) T-maze test to gauge effects on working memory performance. A significant baseline enhancement of working memory performance with HCN channel knockdown was observed, indicative of a critical role for interneuron-expressed HCNs in maintaining optimal cortical network activity during cognitively-demanding tasks. Consistent with previous observations, ethanol exposure resulted in enhanced NMS T-maze performance, however elevated working memory performance was observed in both scram- and hcn-shRNA infected groups after alcohol administration. We therefore conclude that interneuron-expressed HCN channels, despite representing a minor population of total cortical HCN expression, contribute substantially to maintaining working memory processes. Downregulated HCN channel activity, though, does not alone appear sufficient to manifest alcohol-induced enhancement of working memory performance observed in female rats during acute withdrawal., (Copyright © 2024 Elsevier Inc. All rights reserved.)

Background: Neuroimmune dysfunction in alcohol use disorder (AUD) is associated with activation of myeloid differentiation primary response 88 (MyD88)-dependent Toll-like receptors (TLR) resulting in overexpression of the chemokine monocyte chemoattractant protein-1 (MCP-1/CCL2). MCP-1 overexpression in the brain is linked to anxiety, higher alcohol intake, neuronal death, and activation of microglia observed in AUD. The neurosteroid [3α,5α][3-hydroxypregnan-20-one (3α,5α-THP) has been reported as an inhibitor of MyD88-dependent TLR activation and MCP-1 overexpression in mouse and human macrophages and the brain of alcohol-preferring (P) rats., Methods: We investigated how 3α,5α-THP regulates MCP-1 expression at the cellular level in P rat nucleus accumbens (NAc) and central amygdala (CeA). We focused on neurons, microglia, and astrocytes, examining the individual voxel density of MCP-1, neuronal marker NeuN, microglial marker IBA1, astrocytic marker GFAP, and their shared voxel density, defined as intersection. Ethanol-naïve male and female P rats were perfused 1 h after IP injections of 15 mg/kg of 3α,5α-THP, or vehicle. The NAc and CeA were imaged using confocal microscopy following double-immunofluorescence staining for MCP-1 with NeuN, IBA1, and GFAP, respectively., Results: MCP-1 intersected with NeuN predominantly and IBA1/GFAP negligibly. 3α,5α-THP reduced MCP-1 expression in NeuN-labeled cells by 38.27 ± 28.09% in male and 56.11 ± 21.46% in female NAc, also 37.99 ± 19.53% in male and 54.96 ± 30.58% in female CeA. In females, 3α,5α-THP reduced the MCP-1 within IBA1 and GFAP-labeled voxels in the NAc and CeA. Conversely, in males, 3α,5α-THP did not significantly alter the MCP-1 within IBA1 in NAc or with GFAP in the CeA. Furthermore, 3α,5α-THP decreased levels of IBA1 in both regions and sexes with no impact on GFAP or NeuN levels. Secondary analysis performed on data normalized to % control values indicated that no significant sex differences were present., Conclusions: These data suggest that 3α,5α-THP inhibits neuronal MCP-1 expression and decreases the proliferation of microglia in P rats. These results increase our understanding of potential mechanisms for 3α,5α-THP modulation of ethanol consumption., (© 2024 Research Society on Alcohol.)

Key Clinical Message: Creutzfeldt-Jakob disease is a neurodegenerative disorder caused by brain accumulation of a misfolded form of the cellular prion protein, whose diagnosis is challenging, particularly in early stages, due to the variability and nonspecificity of the clinical and radiological features. 18F-fluorodeoxyglucose positron-emitted tomography has the potential to be considered a crucial investigation in these patients, revealing metabolic abnormalities earlier than the conventional neuroimaging analysis., Abstract: A 59-year-old man, the military officer, was referred to our Units for the onset of neurological symptoms rapidly evolving within a month, characterized by akinetic mutism, constructional apraxia, and disorders of spatial orientation. Brain 18F-fluorodeoxyglucose (18F-FDG) positron-emitted tomography (PET)/CT depicted an asymmetric hypometabolism in the left fronto-temporo-parietal cortex, as well as in the left thalamus and the right cerebellar hemisphere, while the glucose metabolism appears to be preserved in the somatosensory cortex and the basal ganglia. Laboratory routine analyses, cerebrospinal fluid routine, infective tests, electroencephalography (EEG), and brain magnetic resonance (MR) were all unremarkable. A positive RT-QuIC result on cerebro-spinal fluid (CSF) was subsequently shown, without any pathogenic gene mutations and, therefore, the result was consistent with a diagnosis of sporadic Creutzfeld-Jacob disease. The clinical evolution was quickly unfavorable, and the patient died about 4 months after hospital admission. FDG PET/computed tomography (CT) has the potential to be considered a crucial investigation in these patients, documenting metabolic changes long time before other diagnostic investigations such as CSF, EEG, brain CT, and brain MR, thus suggesting a greater sensitivity of glucose metabolic evaluation in the early stage of the disease in question., Competing Interests: The authors have no conflict of interest to be disclosed., (© 2024 The Author(s). Clinical Case Reports published by John Wiley & Sons Ltd.)

Dynamic nuclear polarization (DNP) is one of the most powerful and versatile hyperpolarization methods to enhance nuclear magnetic resonance (NMR) signals. A major drawback of DNP is the cost and complexity of the required microwave hardware, especially at high magnetic fields and low temperatures. To overcome this drawback and with the focus on the study of nanoliter and subnanoliter samples, this work demonstrates 200 GHz single chip DNP microsystems where the microwave excitation/detection are performed locally on chip without the need of external microwave generators and transmission lines. The single chip integrated microsystems consist of a single or an array of microwave oscillators operating at about 200 GHz for ESR excitation/detection and an RF receiver operating at about 300 MHz for NMR detection. This work demonstrates the possibility of using the single chip approach for the realization of probes for DNP studies at high frequency, high field, and low temperature., (© 2024. The Author(s).)

We report the development of a continuous-wave and pulsed X-band electron spin resonance (ESR) spectrometer for the study of spins on ordered surfaces down to cryogenic temperatures. The spectrometer operates in ultra-high vacuum and utilizes a half-wavelength microstrip line resonator realized using epitaxially grown copper films on single crystal Al2O3 substrates. The one-dimensional microstrip line resonator exhibits a quality factor of more than 200 at room temperature, close to the upper limit determined by radiation losses. The surface characterizations of the copper strip of the resonator by atomic force microscopy, low-energy electron diffraction, and scanning tunneling microscopy show that the surface is atomically clean, flat, and single crystalline. Measuring the ESR spectrum at 15 K from a few nm thick molecular film of YPc2, we find a continuous-wave ESR sensitivity of 2.6 × 1011 spins/G · Hz1/2, indicating that a signal-to-noise ratio of 3.9 G · Hz1/2 is expected from a monolayer of YPc2 molecules. Advanced pulsed ESR experimental capabilities, including dynamical decoupling and electron-nuclear double resonance, are demonstrated using free radicals diluted in a glassy matrix., (© 2024 Author(s). Published under an exclusive license by AIP Publishing.)

Rationale: Multiple psychiatric disorders are associated with altered brain and serum levels of neuroactive steroids, including the endogenous GABAergic steroid, allopregnanolone. Clinically, chronic cocaine use was correlated with decreased levels of pregnenolone. Preclinically, the effect of acute cocaine on allopregnanolone levels in rodents has had mixed results, showing an increase or no change in allopregnanolone levels in some brain regions., Objective: We hypothesized that cocaine acutely increases allopregnanolone levels, but repeated cocaine exposure decreases allopregnanolone levels compared to controls., Methods: We performed two separate studies to determine how systemic administration of 15 mg/kg cocaine (1) acutely or (2) chronically alters brain (olfactory bulb, frontal cortex, dorsal striatum, and midbrain) and serum allopregnanolone levels in adult male and female Sprague-Dawley rats., Results: Cocaine acutely increased allopregnanolone levels in the midbrain, but not in olfactory bulb, frontal cortex, or dorsal striatum. Repeated cocaine did not persistently (24 h later) alter allopregnanolone levels in any region in either sex. However, allopregnanolone levels varied by sex across brain regions. In the acute study, we found that females had significantly higher allopregnanolone levels in serum and olfactory bulb relative to males. In the repeated cocaine study, females had significantly higher allopregnanolone levels in olfactory bulb, frontal cortex, and serum. Finally, acute cocaine increased allopregnanolone levels in the frontal cortex of females in proestrus, relative to non-proestrus stages., Conclusion: Collectively these results suggest that allopregnanolone levels vary across brain regions and by sex, which may play a part in differential responses to cocaine by sex., (© 2024. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)