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Magnetic two-dimensional (2D) semiconductors have attracted a lot of attention because modern preparation techniques are capable of providing single-crystal films of these materials with precise control of thickness down to the single-layer limit. It opens up a way to study a rich variety of electronic and magnetic phenomena with promising routes toward potential applications. We have investigated the initial stages of epitaxial growth of the magnetic van der Waals semiconductor FeBr2on a single-crystal Au(111) substrate by means of low-temperature scanning tunneling microscopy (STM), low-energy electron diffraction (LEED), X-ray photoemission spectroscopy (XPS), low-energy electron emission microscopy (LEEM), and X-ray photoemission electron microscopy (XPEEM). Magnetic properties of the one- and two-layer thick films were measured via X-ray absorption spectroscopy (XAS) and X-ray magnetic circular dichroism (XMCD). Our findings show a striking difference in the magnetic behavior of the single layer of FeBr2and its bulk counterpart, which can be attributed to the modifications in the crystal structure due to the interaction with the substrate.

IMPORTANCE: Although several clinician- and patient-reported outcome measures have been developed for trials in hidradenitis suppurativa (HS), there is currently no consensus on which measures are best suited for use in clinical practice. Identifying validated and feasible measures applicable to the practice setting has the potential to optimize treatment strategies and generate generalizable evidence that may inform treatment guidelines. OBJECTIVE: To establish consensus on a core set of clinician- and patient-reported outcome measures recommended for use in clinical practice and to establish the appropriate interval within which these measures should be applied. EVIDENCE REVIEW: Clinician- and patient-reported HS measures and studies describing their psychometric properties were identified through literature reviews. Identified measures comprised an item reduction survey and subsequent electronic Delphi (e-Delphi) consensus rounds. In each consensus round, a summary of outcome measure components and scoring methods was provided to participants. Experts were provided with feasibility characteristics of clinician measures to aid selection. Consensus was achieved if at least 67% of respondents agreed with use of a measure in clinical practice. FINDINGS: Among HS experts, response rates for item reduction, e-Delphi round 1, and e-Delphi round 2 surveys were 76.4% (42 of 55), 90.5% (38 of 42), and 92.9% (39 of 42), respectively; among patient research partners (PRPs), response rates were 70.8% (17 of 24), 100% (17 of 17), and 82.4% (14 of 17), respectively. The majority of experts across rounds were practicing dermatologists with 18 to 19 years of clinical experience. In the final e-Delphi round, most PRPs were female (12 [85.7%] vs 2 males [11.8%]) and aged 30 to 49 years. In the final e-Delphi round, HS experts and PRPs agreed with the use of the HS Investigator Global Assessment (28 [71.8%]) and HS Quality of Life score (13 [92.9%]), respectively. The most expert-preferred assessment interval in which to apply these measures was 3 months (27 [69.2%]). CONCLUSIONS AND RELEVANCE: An international group of HS experts and PRPs achieved consensus on a core set of HS measures suitable for use in clinical practice. Consistent use of these measures may lead to more accurate assessments of HS disease activity and life outcomes, facilitating shared treatment decision-making in the practice setting.

La viruela del mono (VDM) se había considerado históricamente una enfermedad zoonótica relegada a áreas donde existe un reservorio animal concreto, con limitada capacidad para propagarse entre humanos. Sin embargo, el estudio de esta enfermedad ha cobrado una reciente actualidad por el aumento creciente de su incidencia en áreas no endémicas, así como la objetivación de la transmisibilidad entre personas. Presentamos el caso de un varón de 27años con lesiones cutáneas y úlceras perianales sugestivas de infección viral en el que se confirmó la infección por virus de la VDM mediante PCR. En el estudio histológico de las lesiones ulceradas perianales encontramos el patrón general de esta infección viral, que se discute en este artículo, junto a sus posibles diagnósticos diferenciales, y un hallazgo característico, que es la afectación de las glándulas ecrinas. Este hallazgo puede orientar el diagnóstico histológico de lesiones cutáneas ulceradas en el contexto clínico de sospecha de VDM.

Retrorectal cystic hamartoma (also known as tailgut cyst) is a congenital lesion that originates from debris from the embryonic caudal intestine. Incidentally diagnosed in more than half of cases, the treatment of choice is surgical resection. It is a very rare pathology whose oncological transformation constitutes a true pathological rarity.

•The Kernohan-Woltman notch phenomenon consists of a hemiparesis involving the limbs on the same side of the triggering intracranial pathology, caused by compression of the contralateral cerebral peduncle against the tentorial edge.•The pathophysiological role of arterial ischemia in this setting has not been studied in depth, but it could account for the variability in the morphology and extent of the mesencephalic lesions observed in association with the Kernohan-Woltman notch phenomenon.

Since the crossed control of sensitive-motor body functions by the contralateral cerebral hemispheres was recognized in the early 18th century, clinicians have been baffled by patients developing a motor deficit involving the extremities on the same side as an intracranial lesion. In the first third of the 20th century, three main hypotheses were proposed to explain this so-called ipsilateral or paradoxical hemiparesis: (1) the absence of decussation of the corticospinal tracts; (2) diaschisis, or blocking of the normal input to a brain region anatomically distant from the injured site; and (3) compression of the contralateral cerebral peduncle against the tentorial border, also known as the Kernohan–Woltman notch phenomenon. Here, we deal with the less widely known contributions of the Belgian neurosurgeon Léon Ectors, who included this paradoxical deficit within a neurological syndrome he considered highly specific for an early diagnosis of those meningiomas growing over the third frontal convolution. The present manuscript includes a systematic review of the cases of ipsilateral hemiparesis secondary to intracranial masses reported in ancient and modern scientific medical literature. We also address in-depth the physiopathological theories accounting for this syndrome and contrast them with Léon Ectors’ observations.

Spin-hosting graphene nanostructures are promising metal-free systems for elementary quantum spintronic devices. Conventionally, spins are protected from quenching by electronic band gaps, which also hinder electronic access to their quantum state. Here, we present a narrow graphene nanoribbon substitutionally doped with boron heteroatoms that combines a metallic character with the presence of localized spin 1/2 states in its interior. The ribbon was fabricated by on-surface synthesis on a Au(111) substrate. Transport measurements through ribbons suspended between the tip and the sample of a scanning tunneling microscope revealed their ballistic behavior, characteristic of metallic nanowires. Conductance spectra show fingerprints of localized spin states in the form of Kondo resonances and inelastic tunneling excitations. Density functional theory rationalizes the metallic character of the graphene nanoribbon due to the partial depopulation of the valence band induced by the boron atoms. The transferred charge builds localized magnetic moments around the boron atoms. The orthogonal symmetry of the spin-hosting state’s and the valence band’s wave functions protects them from mixing, maintaining the spin states localized. The combination of ballistic transport and spin localization into a single graphene nanoribbon offers the perspective of electronically addressing and controlling carbon spins in real device architectures.

This study investigates the presence of a hollow recess at the midline undersurface of tumors primarily localized within the third ventricle (3V). This structure was originally identified by magnetic resonance imaging (MRI) of 6 3V craniopharyngiomas (CPs) from our series and was then methodically scrutinized in autopsy studies (n = 1091) and MRI scans (n = 5558) of CPs and in 1251 3V tumors reported in the medical literature from 1839 to 2021. A recess at the tumor base was identified in 110 CPs, 95 with a verified papillary histology (papillary craniopharyngioma [PCP]) and 15 with typical gross appearance of PCP. Topographically, 90 tumors were strictly within the 3V (82%); 20 developed at the infundibulo-tuberal region of the 3V floor (18%). Morphologically, 2 main types of recess were identified: (i) a long, narrow recess with either a duct-like or a tubular shape that reached the central region of the CP (n = 47, 42.5%); and (ii) a short recess extending only a few millimeters into the lesion, either with a duct-like or a shallow cleft-like morphology (n = 63, 57.5%). Thus, the presence of a basal recess represents a pathological hallmark of a subpopulation of 3V PCPs. The presumed nature and diagnostic significance of this novel finding is comprehensively addressed.

Metal halides are a class of layered materials with promising electronic and magnetic properties persisting down to the two-dimensional limit. While most recent studies focused on the trihalide components of this family, the rather unexplored metal dihalides are also van der Waals layered systems with distinctive magnetic properties. Here we show that the dihalide NiBr2grows epitaxially on a Au(111) substrate and exhibits semiconducting and magnetic behavior starting from a single layer. Through a combination of a low-temperature scanning-tunneling microscopy, low-energy electron diffraction, X-ray photoelectron spectroscopy, and photoemission electron microscopy, we identify two competing layer structures of NiBr2coexisting at the interface and a stoichiometrically pure layer-by-layer growth beyond. Interestingly, X-ray absorption spectroscopy measurements revealed a magnetically ordered state below 27 K with in-plane magnetic anisotropy and zero-remanence in the single layer of NiBr2/Au(111), which we attribute to a noncollinear magnetic structure. The combination of such two-dimensional magnetic order with the semiconducting behavior down to the 2D limit offers the attractive perspective of using these films as ultrathin crystalline barriers in tunneling junctions and low-dimensional devices.

Purpose: To compare the results of early versus late switch to the dexamethasone intravitreal implant Ozurdex®in patients with diabetic macular edema who had a poor response to vascular endothelial growth factor inhibitors.Methods: Retrospective and single-center study conducted, in a real setting, on consecutive diabetic macular edema patients who were switch to an intravitreal dexamethasone implant after a poor response to anti-vascular endothelial growth factor treatment. Study sample was divided into two groups: (1) early-switch group, included those eyes who received three anti-vascular endothelial growth factor injections before switch and (2) late-switch group, included those eyes that received six or more anti-vascular endothelial growth factor injections before switch. The primary end-point was the difference in mean change in best-corrected visual acuity and in central subfoveal thickness.Results: A total of 69 (31 early-switch group and 38 late-switch group) eyes were included. In the early-switch group, median (25–75 quartile range) best-corrected visual acuity significantly increase from 0.2 (0.2–0.5) at baseline to 0.4 (0.3 –0.7) at month 24 (p = 0.0043). Whereas, in the late-switch group, best-corrected visual acuity did not increase (p = 0.8602). Central subfoveal thickness was significantly reduced in both early- and late-switch groups, p = 0.0002 and 0.0038, respectively. The proportion of eyes obtaining a central subfoveal thickness reduction ⩾ 10% was significantly greater in the early-switch group than in the late-switch group (71.0% vs 47.4%, respectively, p = 0.0498). Three (9.7%) and 10 (26.3%) eyes have developed ocular hypertension during the study in the early- and late-switch groups, respectively, p = 0.0816.Conclusion: Early switch to Ozurdex in patients who did not adequately respond to anti-vascular endothelial growth factor therapy provided better functional and anatomical outcomes.

Eigenstate multifractality is a distinctive feature of noninteracting disordered metals close to a metal–insulator transition, whose properties are expected to extend to superconductivity. While multifractality in three dimensions (3D) only develops near the critical point for specific strong-disorder strengths, multifractality in 2D systems is expected to be observable even for weak disorder. Here we provide evidence for multifractal features in the superconducting state of an intrinsic, weakly disordered single-layer NbSe2by means of low-temperature scanning tunneling microscopy/spectroscopy. The superconducting gap, characterized by its width, depth, and coherence peaks’ amplitude, shows a characteristic spatial modulation coincident with the periodicity of the quasiparticle interference pattern. The strong spatial inhomogeneity of the superconducting gap width, proportional to the local order parameter in the weak-disorder regime, follows a log-normal statistical distribution as well as a power-law decay of the two-point correlation function, in agreement with our theoretical model. Furthermore, the experimental singularity spectrum f(α) shows anomalous scaling behavior typical from 2D weakly disordered systems.

Ab initio wavefunction-based quantum chemical calculations on the geometrical and electronic structure of 3d3ions as dopants in different fluoride lattices are reported in this work. Mn4+-doped K2SiF6, a very promising candidate as red-emitting phosphor to be used in white light-emitting diodes, is studied in the first place. Using previous experience in similar calculations, we performed restricted active space self-consistent field calculations in which the multireference includes three active electrons in mainly Mn 3d, 4s orbitals plus singles and doubles excitations from the F 2p and Mn 3p orbitals, followed by RASPT2 calculations explicitly correlating 59 electrons. The structural parameters (Mn–F equilibrium distances and a1gvibrational frequencies) of the ground 4A2g(t2g3) multiplet, the intraconfigurational a2Eg, a2T1g, and a2T2gmultiplets, and the interconfigurational 4T2g, a4T1g(t2g2eg), and b4T1g(t2geg2) multiplets are calculated using molecular orbitals individually optimized for the different states. Then, electronic transition energies between these states are computed. A large mixing between the levels of the a2T2gand 4T2gmultiplets, due to spin–orbit coupling, is predicted and its consequences are analyzed. We find a systematic (good) agreement between calculated transition energies and experimental results, the spin-forbidden transitions deviate by only around 200 cm–1(including the red emission a2Eg→ 4A2g) and spin-allowed transitions are overestimated by 1000–1500 cm–1, partly as a consequence of the calculated equilibrium distances being too short. Because of this, the 10Dqparameter is somewhat overestimated. The same procedures are applied to Cs2GeF6:Mn4+, KMgF3:Cr3+, and KMgF3:V2+, and we find a very similar, reasonable agreement with experimental findings. This agreement makes us confident that the proposed recipes provide fairly accurate information at a reasonable computational effort for transition metals as dopants in fluoride crystals, both for low and intermediate oxidation states of the impurity.

To assess the levels of a tobacco-specific nitrosamine (NNAL) in non-smokers passively exposed to the second-hand aerosol (SHA) emitted from users of electronic cigarettes (e-cigarettes).

Bulk and single-layer 2H-NbSe2exhibit identical charge density wave order (CDW) with a quasi-commensurate 3 × 3 superlattice periodicity. Here we combine scanning tunnelling microscopy (STM) imaging at T= 1 K of 2H-NbSe2with first-principles density functional theory (DFT) calculations to investigate the structural atomic rearrangement of this CDW phase. Our calculations for single-layers reveal that six different atomic structures are compatible with the 3 × 3 CDW distortion, although all of them lie on a very narrow energy range of at most 3 meV per formula unit, suggesting the coexistence of such structures. Our atomically resolved STM images of bulk 2H-NbSe2unambiguously confirm this by identifying two of these structures. Remarkably, these structures differ from the X-ray crystal structure reported for the bulk 3 × 3 CDW which in fact is also one of the six DFT structures located for the single-layer. Our calculations also show that due to the minute energy difference between the different phases, the ground state of the 3 × 3 CDW could be extremely sensitive to doping, external strain or internal pressure within the crystal. The presence of multiphase CDW order in 2H-NbSe2may provide further understanding of its low temperature state and the competition between different instabilities.

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The Notch pathway regulates key processes in the kidney involved in embryonic development and tissue damage. Local activation of the Notch pathway has been described in many human chronic renal diseases, and has been suggested that several Notch pathway components could be considered as biomarkers of renal damage. Experimental studies done using Notch-components genetic modified mice as well as pharmacological approaches, such as γ-secretase inhibitors that block Notch pathway activation, have demonstrated the role of this pathway in renal regeneration, podocyte apoptosis, proliferation and fibroblasts activation, and induction of epithelial to mesenchymal transition of tubular epithelial cells. Recent studies suggest an interaction between Notch and NF-κB pathways in the regulation of the renal inflammatory process. Additionally, some miRNAs could regulate Notch components and down-stream responses. All these data suggest that blockade of the Notch signaling pathway could be a novel therapeutic option for renal diseases.

La vía de Notch regula procesos importantes en el riñón implicados en el desarrollo embrionario y en situaciones de agresión tisular. Así, en una gran variedad de nefropatías crónicas humanas se ha descrito una activación local de este sistema, sugiriendo que algunos de sus componentes podrían ser biomarcadores de daño renal. Los estudios realizados en modelos experimentales, modulando genéticamente componentes de la vía Notch o mediante su bloqueo farmacológico con inhibidores de la γ-secretasa, han demostrado la participación de esta vía en la regeneración renal, en la apoptosis de podocitos, en la proliferación y activación de fibroblastos y en la transición epitelio-mesenquimal de las células tubuloepiteliales. Estudios recientes sugieren una interacción entre las vías Notch y NF-κB, la cual podría jugar un papel relevante en el proceso inflamatorio renal. Por otra parte, en los últimos años se han descrito miRNA que son capaces de regular componentes de la vía Notch y modular sus respuestas. Todos estos datos indican que el bloqueo de la vía de señalización Notch podría representar una nueva opción terapéutica para la enfermedad renal.

Intervenciones diferentes pueden mejorar el control del colesterol unido a lipoproteínas de baja densidad (cLDL). El objetivo principal era evaluar la eficacia de una intervención combinada para mejorar el control del cLDL de pacientes con hipercolesterolemia. También se evaluó su eficacia para mejorar el cumplimiento (farmacológico, dieta y ejercicio).

La apendicectomía laparoscópica por puerto único supone un avance en las técnicas mínimamente invasivas. El objetivo de este estudio es mostrar nuestra serie de 100 casos de apendicitis aguda, intervenidos mediante técnica de puerto único utilizando el sistema «glove port», exponiendo nuestra técnica, resultados y seguimiento de nuestros pacientes.

Band gap engineering in hydrogen functionalized graphene is demonstrated by changing the symmetry of the functionalization structures. Small differences in hydrogen adsorbate binding energies on graphene on Ir(111) allow tailoring of highly periodic functionalization structures favoring one distinct region of the moiré supercell. Scanning tunneling microscopy and X-ray photoelectron spectroscopy measurements show that a highly periodic hydrogen functionalized graphene sheet can thus be prepared by controlling the sample temperature (Ts) during hydrogen functionalization. At deposition temperatures of Ts= 645 K and above, hydrogen adsorbs exclusively on the HCP regions of the graphene/Ir(111) moiré structure. This finding is rationalized in terms of a slight preference for hydrogen clusters in the HCP regions over the FCC regions, as found by density functional theory calculations. Angle-resolved photoemission spectroscopy measurements demonstrate that the preferential functionalization of just one region of the moiré supercell results in a band gap opening with very limited associated band broadening. Thus, hydrogenation at elevated sample temperatures provides a pathway to efficient band gap engineering in graphene viathe selective functionalization of specific regions of the moiré structure.