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Cutaneous squamous cell carcinoma (cSCC) comprises 20% of cases of nonmelanoma skin cancers in the United States. In total, 3% to 5% of squamous cell carcinoma (SCC) are metastatic at the time of presentation, associated with significant mortality due to a lack of standardized treatment options. In total, 95% of these tumors are amenable to the initial standard of treatment, which is surgical resection. However, a small percentage of them require systemic therapy as they are either locally advanced to regional lymph nodes or have distant metastasis. The common sites of presentation of cSCC are the scalp and the face with predictable spread to the intra-parotid, upper jugular, and perifacial lymph nodes. In our case report, however, our patient had a large lump lesion on the upper back, an unusual site of presentation of cSCC, with locally advanced metastasis to the left axillary lymph nodes. Subsequently, the tumor marker study revealed a positive SMARCA4 variant (the essential ATPase subunit of the Switch (SWI)/Sucrose Nonfermenting (SNF) chromatin-remodeling complex) that is even rarer in the context of cSCC. Furthermore, abnormalities in SWI/SNF chromatin-remodeling complex subunits have shown promising results as a target therapy for immune checkpoint inhibitor (ICI) therapy. We present an atypical presentation site of locally advanced rare variant SMARCA4-positive cSCC in a patient who received treatment with chemoradiation and systemic therapy with ICI after primary surgical resection. To date, only 2 cases of SMARCA4-positive cSCC were found in the literature with no details of the treatment received. Our case is unique in its atypical site of presentation as well as showing partial response to radiotherapy (RT) and systemic therapy with ICI.

This paper analyses the statistical parameters that give a comprehensive overview of the socio-demographic state of the border areas of Bosnia and Herzegovina, and it represents a novel attempt to examine the disparity and relationships between central and peripheral parts of national territory. The methodology is based on examining the differences between border and non-border municipalities/cities according to four groups of indicators, to obtain four indices: depopulation, natural change, ageing and education. Statistically significant differences were found primarily in the context of population age structure, and it can be concluded that the ageing process has affected bordering regions more than the rest of the country.

Plasmablastic lymphoma (PBL) is a rare but aggressive subtype of diffuse large B-cell lymphoma (DLBCL). The diagnosis of PBL is challenging as its features overlap with lymphoma and myeloma. The most common presentation involves the oral cavity/jaw in human immunodeficiency virus (HIV)–positive patients. It has also been reported in the gastrointestinal (GI) tract, lymph nodes, and soft tissues. Usually, if PBL involves the GI tract, it presents as a gut tumor mass. In this report, we present an HIV-positive patient with PBL presenting with multiple peritoneal nodules. To our knowledge, this is the first case of PBL presenting as multiple peritoneal and retroperitoneal nodules in an HIV-positive patient. This case emphasizes the rare presentation of a rare malignancy, difficulties in establishing a diagnosis, and the importance of proper and timely management.

Primary bone marrow lymphoma (PBML) is a disease entity in which lymphoma primarily originates in the bone marrow without signs of involvement of lymph nodes, spleen, liver, or any other organs, and excludes leukemia/lymphoma. PBML has been a rare presentation of malignant lymphoma, and most of the cases have a poor prognosis and require rapid diagnoses and treatments. Among all PBMLs, diffuse large B-cell lymphoma (DLBCL) is the most common pathological subtype. Over 25 years and from 7 institutions, the International Extranodal Lymphoma Study Group retrospectively collected PBML cases and, in 2012, published these 21 cases, including 19 cases of B-cell lymphoma and 2 cases of peripheral T-cell lymphoma. Among the B-cell types, DLBCL accounted for 79% and follicular lymphoma (FL) for 21%. DLBCLs were characterized by the existence of large cells. In this article, we present a rare case of high-grade aggressive type with P53 mutation, intermediate-sized B-cell lymphoma, excluded FL by the absence of FL lymphoma markers, presented as PBML. Our patient had rapid progression and succumbed to the disease shortly after diagnosis. Upon literature review, 62 B-cell lymphoma cases were identified that presented as PBML (51 high-grade and 11 low-grade)—mostly case reports. Among these, only one case was reported as intermediate-sized DLBCL-like lymphoma but not with aggressive features. Our case represents the first case of aggressive intermediate-sized lymphoma, not a FL, with P53 mutation, highly elevated lactate dehydrogenase, and Ki-67 presented as PBML. Such a profile would need to be quickly recognized and aggressive treatment applied, such as CART (chimeric antigen receptor T-cells) therapy or DA-EPOCH-R (dose-adjusted EPOCH [etoposide-prednisone-oncovin-cyclophosphamide-hydroxydaunorubicin] and rituximab) with or without venetoclax.

The hallmark of Polycythemia vera (PV) is the presence of JAK2V617F mutation and increased RBC mass. Chronic myelomonocytic leukemia (CMML) is defined as persistent blood absolute monocyte count (AMC) >/= 1 × 109/L for at least 3 months with myeloid cell dysplasia. Few cases of evolved CMML from PV have been described. We present a case of PV that progressed to CMML. We demonstrated the CMML clone was most likely derived from PV- JAK2V617F clone. This clone carried a complex genetic mutations of ASXL1, RUNX1, SRSF2 and TET2, NRAS, KRAS, plus CMML cells were of the classical phenotype CD14+ CD16−by flow cytometry. Keywords: Chronic myelomonocytic leukemia, Polycythemia vera, Monocytosis

The paper describes the use of a single-phase three-stage solid-state transformer in networks with non-sinusoidal voltages in order to improve the quality of electricity. An active-inductive load was chosen as the load. The solid-state transformer was simulated by the Matlab/Simulink software. Its performance was analyzed and the parameters for optimal performance were specified. The voltage and current graphs on the load and their spectral analysis are given. Total harmonic distortion was evaluated for current and voltage. As a comparison, the operation of a classic transformer was simulated. Modeling shows that solid-state transformer copes with improving the quality of electricity better than a classical transformer. In addition to improving the quality of the load current, the solid-state transformer protects the consumer from overvoltage, voltage dips, and other transient phenomena, due to the accumulated supply of electricity in the capacitors of the DC-Bus.

The magnetic field distribution along the radius and height in the working chamber of a hydrocyclone with a radial magnetic field is studied. One of the most important parameters of magnetic hydrocyclones is the magnetic field distribution along the radius and height of the working chamber. It is necessary for calculating the coagulation forces and the magnetic force affecting the particle or flocculus. The magnetic field strength was calculated through magnetic induction, measured by a teslameter at equal intervals and at different values of the supply DC current. The obtained values for the magnetic field strength are presented in the form of graphs. The field distribution curves produced from the dependences found earlier were constructed. The correlation coefficients were calculated. It was proven that the analyzed dependences could be used in further calculations of coagulation forces and magnetic force, because theoretical and experimental data compared favourably with each other. The distribution along the radius and height in the cylindrical part of the magnetic hydrocyclone was consistent with data published in the scientific literature.

Malignant fibrous histiocytoma (MFH) is the most common sarcoma found in adults. We discuss a case of inflammatory MFH of dermal/epidermal origin presenting with a severe leukemoid reaction (LR). A 60 years old white male presented to hematology/oncology clinic complaining of mild shortness of breath on exertion. Past medical history was remarkable for removal of a left upper extremity necrotic mass 4.4 × 3 × 3 cm. Microscopy of the specimen showed clear surgical margin, and tumor cells restricted to the dermis without lymphovascular invasion. Immunohistochemestry was positive for CD 68 and CD 99. Chest x-ray was negative for metastatic disease. White blood cell count was 109.4 k/mm3 with 24 k/mm3 band neutrophils, and absolute neutrophil count of 69 k/mm3. CT scan of the thorax revealed numerous bilateral pulmonary nodules suspicious for metastasis. Based on these findings patient was diagnosed with metastatic cutaneous IMFH associated with a LR. Following review of medical literature, this appears to be the first reported case of inflammatory cutaneous MFH associated with LR. This histological variant is rare, and carries a poor prognosis. Thus, we would like to emphasize the need for investigating alternative therapies capable of improving the survival of these patients.

In quantum materials, degeneracies and frustrated interactions can have a profound impact on the emergence of long-range order, often driving strong fluctuations that suppress functionally relevant electronic or magnetic phases 1-7 . Engineering the atomic structure in the bulk or at heterointerfaces has been an important research strategy to lift these degeneracies, but these equilibrium methods are limited by thermodynamic, elastic and chemical constraints 8 . Here we show that all-optical, mode-selective manipulation of the crystal lattice can be used to enhance and stabilize high-temperature ferromagnetism in YTiO 3 , a material that shows only partial orbital polarization, an unsaturated low-temperature magnetic moment and a suppressed Curie temperature, T c  = 27 K (refs. 9-13 ). The enhancement is largest when exciting a 9 THz oxygen rotation mode, for which complete magnetic saturation is achieved at low temperatures and transient ferromagnetism is realized up to T neq  > 80 K, nearly three times the thermodynamic transition temperature. We interpret these effects as a consequence of the light-induced dynamical changes to the quasi-degenerate Ti t 2g orbitals, which affect the magnetic phase competition and fluctuations found in the equilibrium state 14-20 . Notably, the light-induced high-temperature ferromagnetism discovered in our work is metastable over many nanoseconds, underscoring the ability to dynamically engineer practically useful non-equilibrium functionalities., (© 2023. The Author(s).)

We have used atomic layer-by-layer oxide molecular beam epitaxy to grow epitaxial thin films of [Formula: see text] with x up to 0.5, greatly exceeding the solubility limit of Ca in bulk systems ([Formula: see text]). A comparison of the optical conductivity measured by spectroscopic ellipsometry to prior predictions from dynamical mean-field theory demonstrates that the hole concentration p is approximately equal to x. We find superconductivity with [Formula: see text] of 15 to 20 K up to the highest doping levels and attribute the unusual stability of superconductivity in [Formula: see text] to the nearly identical radii of La and Ca ions, which minimizes the impact of structural disorder. We conclude that careful disorder management can greatly extend the "superconducting dome" in the phase diagram of the cuprates., Competing Interests: The authors declare no competing interest., (Copyright © 2021 the Author(s). Published by PNAS.)

The temperature dependence of the superfluid density ρ_{s}(T) has been measured for a series of ultrathin MBE-grown DyBa_{2}Cu_{3}O_{7-δ} superconducting (SC) films by submillimeter wave interferometry combined with time-domain terahertz spectroscopy and IR ellipsometry. We find that all films 10 u.c. and thicker show the same universal temperature dependence of ρ_{s}(T), which follows the critical behavior characteristic of single crystal YBa_{2}Cu_{3}O_{7-δ} as T approaches T_{c}. In 7 u.c. thick films, ρ_{s}(T) declines steeply upon approaching T_{c}, as expected for the Berezinskii-Kosterlitz-Thouless vortex unbinding transition. Our analysis provides evidence for a sharply defined 4 u.c. non-SC interfacial layer, leaving a quasi-2D SC layer on top. We propose that the SC state in this interfacial layer is suppressed by competing (possibly charge) order.

In high-energy physics, the Higgs field couples to gauge bosons and fermions and gives mass to their elementary excitations. Experimentally, such couplings can be inferred from the decay product of the Higgs boson, i.e., the scalar (amplitude) excitation of the Higgs field. In superconductors, Cooper pairs bear a close analogy to the Higgs field. Interaction between the Cooper pairs and other degrees of freedom provides dissipation channels for the amplitude mode, which may reveal important information about the microscopic pairing mechanism. To this end, we investigate the Higgs (amplitude) mode of several cuprate thin films using phase-resolved terahertz third harmonic generation (THG). In addition to the heavily damped Higgs mode itself, we observe a universal jump in the phase of the driven Higgs oscillation as well as a non-vanishing THG above T c . These findings indicate coupling of the Higgs mode to other collective modes and potentially a nonzero pairing amplitude above T c .

We report the first determination of the in-plane complex optical conductivity of 1111 high-T_{c} superconducting iron oxypnictide single crystals PrFeAs(O,F) and thin films SmFeAs(O,F) by means of conventional and microfocused infrared spectroscopy, ellipsometry, and time-domain THz transmission spectroscopy. A strong itinerant contribution is found to exhibit a dramatic difference in coherence between the crystal and the film. Using extensive temperature-dependent measurements of THz transmission, we identify a previously undetected 2.5-meV collective mode in the optical conductivity of SmFeAs(O,F), which is strongly suppressed at T_{c} and experiences an anomalous T-linear softening and narrowing below T^{*}≈110  K≫T_{c}. The suppression of the infrared absorption in the superconducting state reveals a large optical superconducting gap with a similar gap ratio 2Δ/k_{B}T_{c}≈7 in both materials, indicating strong pairing.

The excitonic insulator is a long conjectured correlated electron phase of narrow-gap semiconductors and semimetals, driven by weakly screened electron-hole interactions. Having been proposed more than 50 years ago, conclusive experimental evidence for its existence remains elusive. Ta 2 NiSe 5 is a narrow-gap semiconductor with a small one-electron bandgap E G of <50 meV. Below T C =326 K, a putative excitonic insulator is stabilized. Here we report an optical excitation gap E op ∼0.16 eV below T C comparable to the estimated exciton binding energy E B . Specific heat measurements show the entropy associated with the transition being consistent with a primarily electronic origin. To further explore this physics, we map the T C -E G phase diagram tuning E G via chemical and physical pressure. The dome-like behaviour around E G ∼0 combined with our transport, thermodynamic and optical results are fully consistent with an excitonic insulator phase in Ta 2 NiSe 5 .

Iron-based superconductors have been found to exhibit an intimate interplay of orbital, spin, and lattice degrees of freedom, dramatically affecting their low-energy electronic properties, including superconductivity. Albeit the precise pairing mechanism remains unidentified, several candidate interactions have been suggested to mediate the superconducting pairing, both in the orbital and in the spin channel. Here, we employ optical spectroscopy (OS), angle-resolved photoemission spectroscopy (ARPES), ab initio band-structure, and Eliashberg calculations to show that nearly optimally doped NaFe0.978Co0.022As exhibits some of the strongest orbitally selective electronic correlations in the family of iron pnictides. Unexpectedly, we find that the mass enhancement of itinerant charge carriers in the strongly correlated band is dramatically reduced near the Γ point and attribute this effect to orbital mixing induced by pronounced spin-orbit coupling. Embracing the true band structure allows us to describe all low-energy electronic properties obtained in our experiments with remarkable consistency and demonstrate that superconductivity in this material is rather weak and mediated by spin fluctuations.

A combined synchrotron X-ray diffraction and transmission electron microscopy study reveals a structural phase transition controlled by the overall thickness of epitaxial nickelate-aluminate superlattices. The transition between uniform and twin-domain states is confined to the nickelate layers and leaves the aluminate layers unaffected., (© 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.)

We study the model high-temperature superconductor HgBa(2)CuO(4+δ) with electronic Raman scattering and optical ellipsometry over a wide doping range. The dependence of the resonant Raman cross section on the incident photon energy changes drastically as a function of doping, in a manner that corresponds to a rearrangement of the interband optical transitions seen with ellipsometry. This doping-dependent Raman resonance allows us to reconcile the apparent discrepancy between Raman and x-ray detection of magnetic fluctuations in superconducting cuprates. Intriguingly, the strongest variation occurs across the doping level where the antinodal superconducting gap appears to reach its maximum.

We have used resonant x-ray diffraction to develop a detailed description of antiferromagnetic ordering in epitaxial superlattices based on two-unit-cell thick layers of the strongly correlated metal LaNiO3. We also report reference experiments on thin films of PrNiO3 and NdNiO3. The resulting data indicate a spiral state whose polarization plane can be controlled by adjusting the Ni d-orbital occupation via two independent mechanisms: epitaxial strain and spatial confinement of the valence electrons. The data are discussed in light of recent theoretical predictions.

We studied phase separation in the single-crystalline antiferromagnetic superconductor Rb(2)Fe(4)Se(5) (RFS) using a combination of scattering-type scanning near-field optical microscopy and low-energy muon spin rotation (LE-μSR). We demonstrate that the antiferromagnetic and superconducting phases segregate into nanometer-thick layers perpendicular to the iron-selenide planes, while the characteristic in-plane size of the metallic domains reaches 10  μm. By means of LE-μSR we further show that in a 40-nm thick surface layer the ordered antiferromagnetic moment is drastically reduced, while the volume fraction of the paramagnetic phase is significantly enhanced over its bulk value. Self-organization into a quasiregular heterostructure indicates an intimate connection between the modulated superconducting and antiferromagnetic phases.

The competition between collective quantum phases in materials with strongly correlated electrons depends sensitively on the dimensionality of the electron system, which is difficult to control by standard solid-state chemistry. We have fabricated superlattices of the paramagnetic metal lanthanum nickelate (LaNiO(3)) and the wide-gap insulator lanthanum aluminate (LaAlO(3)) with atomically precise layer sequences. We used optical ellipsometry and low-energy muon spin rotation to show that superlattices with LaNiO(3) as thin as two unit cells undergo a sequence of collective metal-insulator and antiferromagnetic transitions as a function of decreasing temperature, whereas samples with thicker LaNiO(3) layers remain metallic and paramagnetic at all temperatures. Metal-oxide superlattices thus allow control of the dimensionality and collective phase behavior of correlated-electron systems.

One of the central tenets of conventional theories of superconductivity, including most models proposed for the recently discovered iron-pnictide superconductors, is the notion that only electronic excitations with energies comparable to the superconducting energy gap are affected by the transition. Here, we report the results of a comprehensive spectroscopic ellipsometry study of a high-quality crystal of superconducting Ba₀.₆₈K₀.₃₂Fe₂As₂ that challenges this notion. We observe a superconductivity-induced suppression of an absorption band at an energy of 2.5 eV, two orders of magnitude above the superconducting gap energy 2Δ≈20 meV. On the basis of density functional calculations, this band can be assigned to transitions from As-p to Fe-d orbitals crossing the Fermi level. We identify a related effect at the spin-density wave transition in parent compounds of the 122 family. This suggests that As-p states deep below the Fermi level contribute to the formation of the superconducting and spin-density wave states in the iron arsenides.

The specific heat of high-purity Ba(0.68)K(0.32)Fe2As2 single crystals with the highest reported superconducting Tc=38.5 K was studied. The electronic specific heat Cp below Tc shows two gap features, with Δ1≈11 meV and Δ2≈3.5 meV obtained from an α-model analysis. The reduced gap value, 2Δ(max)/kBTc≈6.6, the magnitude of the specific-heat jump, ΔCp(Tc)/Tc, and its slope below Tc exhibit a strong-coupling character. We also show that an Eliashberg model with two hole and two electron bands gives the correct values of Tc, the superconducting gaps, and the free-energy difference.

Spectroscopic ellipsometry was used to study the dielectric function of LiCuVO4, a compound comprised of chains of edge-sharing CuO4 plaquettes, in the spectral range 0.75-6.5 eV at temperatures 7-300 K. For photon polarization along the chains, the data reveal a weak but well-resolved two-peak structure centered at 2.15 and 2.95 eV whose spectral weight is strongly enhanced upon cooling near the magnetic ordering temperature. We identify these features as an exciton doublet in the Mott-Hubbard gap that emerges as a consequence of the Coulomb interaction between electrons on nearest and next-nearest-neighbor sites along the chains. Our results and methodology can be used to address the role of the long-range Coulomb repulsion for compounds with doped copper-oxide chains and planes.

Here we present a combined study of the slightly underdoped novel pnictide superconductor Ba1-xKxFe2As2 by means of x-ray powder diffraction, neutron scattering, muon-spin rotation (microSR), and magnetic force microscopy (MFM). Static antiferromagnetic order sets in below T{m} approximately 70 K as inferred from the neutron scattering and zero-field-microSR data. Transverse-field microSR below Tc shows a coexistence of magnetically ordered and nonmagnetic states, which is also confirmed by MFM imaging. We explain such coexistence by electronic phase separation into antiferromagnetic and superconducting- or normal-state regions on a lateral scale of several tens of nanometers. Our findings indicate that such mesoscopic phase separation can be considered an intrinsic property of some iron pnictide superconductors.

The distribution of valence electrons in metals usually follows the symmetry of the underlying ionic lattice. Modulations of this distribution often occur when those electrons are not stable with respect to a new electronic order, such as spin or charge density waves. Electron density waves have been observed in many families of superconductors, and are often considered to be essential for superconductivity to exist. Recent measurements seem to show that the properties of the iron pnictides are in good agreement with band structure calculations that do not include additional ordering, implying no relation between density waves and superconductivity in these materials. Here we report that the electronic structure of Ba(1-x)K(x)Fe(2)As(2) is in sharp disagreement with those band structure calculations, and instead reveals a reconstruction characterized by a (pi, pi) wavevector. This electronic order coexists with superconductivity and persists up to room temperature (300 K).

Spectroscopic ellipsometry is used to determine the dielectric function of superconducting LaFeAsO0.9F0.1 (T&#95;{c}=27 K) and undoped LaFeAsO polycrystalline samples in the wide range 0.01-6.5 eV at temperatures 10< or =T< or =350 K. The charge carrier response in both samples is heavily damped. The spectral weight transfer in LaFeAsO associated with an opening of the pseudogap at about 0.65 eV is restricted to energies below 2 eV. The spectra of superconducting LaFeAsO0.9F0.1 reveal a significant transfer of spectral weight to a broad optical band above 4 eV with increasing temperature. Our data may imply that the electronic states near the Fermi surface are strongly renormalized due to electron-phonon and/or electron-electron interactions.

We present broadband infrared ellipsometry measurements of the c-axis conductivity of underdoped RBa&#95;{2}Cu&#95;{3}O&#95;{7-delta} (R=Y, Nd, and La) single crystals. Our data show that separate energy scales are underlying the redistributions of spectral weight due to the normal state pseudogap and the superconducting gap. Furthermore, they provide evidence that these gaps do not share the same electronic states and do not merge on the overdoped side. Accordingly, our data are suggestive of a two gap scenario with a pseudogap that is likely extrinsic with respect to superconductivity.

The influence of magnetic Ni and nonmagnetic Zn impurities on the normal-state pseudogap (PG) in the c-axis optical conductivity of (Sm,Nd)Ba(2){Cu(1-y)(Ni,Zn)(y)}(3)O(7-delta) crystals was studied by spectral ellipsometry. We find that these impurities, which strongly suppress superconductivity, have a profoundly different impact on the PG. Zn gives rise to a gradual and inhomogeneous PG suppression while Ni strongly enhances the PG. Our results challenge theories that relate the PG either to precursor superconductivity or to other phases with exotic order parameters, such as flux phase or d-density wave states, that should be suppressed by potential scattering. The apparent difference between magnetic and nonmagnetic impurities instead points towards an important role of magnetic correlations in the PG state.

Using spectral ellipsometry, we measured the dielectric function of a Na(0.82(2))CoO2 crystal that exhibits bulk antiferromagnetism with T(N)=19.8 K. We identify two prominent transitions as a function of temperature. The first one at 280 K involves marked changes of the electronic and lattice responses that are indicative of charge ordering in the CoO2 layers. The second transition occurs around T(N)=19.8 K and reveals sizable spin-charge coupling. The data are discussed in terms of charge ordering and formation of magnetopolarons due to a charge-induced spin-state transition of adjacent Co3+ ions.

Spectral ellipsometry is used to determine the dielectric function of an untwinned crystal of LaMnO3 in the range 0.5-5.6 eV at temperatures 50

The temperature-dependent redistribution of the spectral weight of the CuO2 plane-derived conduction band of the YBa2Cu3O6.9 high-temperature superconductor (superconducting transition temperature = 92.7 kelvin) was studied with wide-band (0.01- to 5.6-electron volt) spectroscopic ellipsometry. A superconductivity-induced transfer of the spectral weight involving a high-energy scale in excess of 1 electron volt was observed. Correspondingly, the charge carrier spectral weight was shown to decrease in the superconducting state. The ellipsometric data also provide detailed information about the evolution of the optical self-energy in the normal and superconducting states.

The electronic and magnetic properties of SrFeO(3-delta) single crystals with controlled oxygen content (0< or =delta< or =0.19) have been studied systematically by susceptibility, transport, and spectroscopic techniques. An intimate correlation between the spin-charge ordering and the electronic transport behavior is found. Giant negative as well as positive magnetoresistance are observed.

The far-infrared (FIR) c axis conductivity of a Bi2223 crystal has been measured by ellipsometry. Below T(c) a strong absorption band develops near 500 cm(-1), corresponding to a transverse Josephson plasmon. The related increase in FIR spectral weight leads to a giant violation of the Ferrell-Glover-Tinkham sum rule. The gain in c axis kinetic energy accounts for a sizable part of the condensation energy. We also observe phonon anomalies which suggest that the Josephson currents lead to a drastic variation of the local electric field within the block of closely spaced CuO2 planes.