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The interaction of europium nitrate with triazine-based luminophores, namely 3-(pyridin-2-yl)triimidazo[1,2-a:1′,2′-c:1″,2′′-e][1,3,5]triazine (L1), 3-(pyridin-4-yl)triimidazo[1,2-a:1′,2′-c:1″,2′′-e][1,3,5]triazine (L2), and 3,7,11-tri(pyridin-4-yl)triimidazo[1,2-a:1′,2′-c:1″,2″-e][1,3,5]triazine (L3), resulted in three Eu(III) compounds with the compositions (L1H)[Eu(NO3)4(H2O)2] (1), (L2HL2)2[Eu(NO3)5(H2O)] (CH3CN)2(2), and [Eu(NO3)3(H2O)2(L3)] (3) whose structures were disclosed by single crystal X-ray diffraction analysis. In the organic–inorganic hybrid salts 1and 2, the direct Eu(III)–triazinic ligand coordination is lacking, while in the neutral complex 3the direct Eu(III)–L3coordination occurs through one of the luminophore’s N-pyridine binding sites. The solid-state photoluminescence behavior of 2and 3was studied. At room temperature, 2revealed predominantly the ligand-based photoluminescence in the cyan-blue region of the spectrum when excited at 337 nm; the orange-red Eu(III)-based emission dominated the spectrum when excited at 405 nm. On the other hand, irrespective of the excitation wavelength, compound 3displayed the characteristic emission of Eu(III), suggesting that the coordinated L3ligand effectively played an antenna effect toward the metal. The Eu(III)-based contribution in photoluminescence in 2and 3displayed an opposite thermochromic behavior when monitored in the 12–300 K range. Specifically, the emission intensity decreases for 2and increases for 3with an increase in the temperature. The unusual thermochromic effect for 3was hypothesized from a density of states (DOS) viewpoint.

Integration of 2D semiconductors with photonic crystal slabs provides an attractive approach to achieving strong light–matter coupling and exciton–polariton formation in a chip-compatible geometry. However, for the development of practical devices, it is crucial that polariton excitations are easily tunable and exhibit a strong nonlinear response. Here we study neutral and charged exciton–polaritons in an electrostatically gated photonic crystal slab with an embedded monolayer semiconductor MoSe2and experimentally demonstrate a novel approach to optical control based on polariton nonlinearity. We show that spatial modulation of the dielectric environment within the photonic crystal unit cell results in the formation of two distinct excitonic species with significantly different nonlinear responses of the corresponding charged exciton–polaritons under optical pumping. This behavior enables optical switching with ultrashort laser pulses and can be sensitively controlled via an electrostatic gate voltage. Our results open new avenues toward the development of active polaritonic devices in a compact chip-compatible implementation.

Twist-controlled moire´ superlattices (MSs) have emerged as a versatile platform for realizing artificial systems with complex electronic spectra. The combination of Bernal-stacked bilayer graphene (BLG) and hexagonal boron nitride (hBN) can give rise to an interesting MS, which has recently featured a set of unexpected behaviors, such as unconventional ferroelectricity and the electronic ratchet effect. Yet, the understanding of the electronic properties of BLG/hBN MS has, at present, remained fairly limited. Here, we combine magneto-transport and low-energy sub-THz excitation to gain insights into the properties of this MS. We demonstrate that the alignment between BLG and hBN crystal lattices results in the emergence of compensated semimetals at some integer fillings of the moire´ bands, separated by van Hove singularities where the Lifshitz transition occurs. A particularly pronounced semimetal develops when eight holes reside in the moire´ unit cell, where coexisting high-mobility electron and hole systems feature strong magnetoresistance reaching 2350% already at B= 0.25 T. Next, by measuring the THz-driven Nernst effect in remote bands, we observe valley splitting, indicating an orbital magnetization characterized by a strongly enhanced effective gv-factor of 340. Finally, using THz photoresistance measurements, we show that the high-temperature conductivity of the BLG/hBN MS is limited by electron–electron umklapp processes. Our multifaceted analysis introduces THz-driven magnetotransport as a convenient tool to probe the band structure and interaction effects in van der Waals materials and provides a comprehensive understanding of the BLG/hBN MS.

Abstract: The main methods describing polarization of electromagnetic waves in weakly anisotropic inhomogeneous media are reviewed: the quasi-isotropic approximation (QIA) of geometrical optics method that deals with coupled equations for electromagnetic field components, and the Stokes vector formalism (SVF), dealing with Stokes vector components, which are quadratic in electromagnetic field intensity. The equation for the Stokes vector evolution is shown to be derived directly from QIA, whereas the inverse cannot be true. Derivation of SVF from QIA establishes a deep unity of these two approaches, which happen to be equivalent up to total phase. It is pointed out that in contrast to QIA, the Stokes vector cannot be applied for a polarization analysis of the superposition of coherent electromagnetic beams. Additionally, the ability of QIA to describe a normal modes conversion in inhomogeneous media is emphasized.

Guided 2D exciton–polaritons, resulting from the strong coupling of excitons in semiconductors with nonradiating waveguide modes, provide an attractive approach toward developing novel on-chip optical devices. These quasiparticles are characterized by long propagation distances and efficient nonlinear interactions but cannot be directly accessed from the free space. Here we demonstrate a powerful approach for probing and manipulating guided polaritons in a Ta2O5slab integrated with a WS2monolayer using evanescent coupling through a high-index solid immersion lens. Tuning the nanoscale lens–sample gap allows for extracting all of the intrinsic parameters of the system. We also demonstrate the transition from weak to strong coupling accompanied by the onset of the motional narrowing effect: with the increase of exciton–photon coupling strength, the inhomogeneous contribution to polariton line width, inherited from the exciton resonance, becomes fully lifted. Our results enable the development of integrated optics employing room-temperature exciton–polaritons in 2D semiconductor-based structures.

A new mixed-valence heterometallic nonanuclear cluster [Mn7Dy2(μ4-O)2(μ3-O)4(μ3-OMe)2(μ2-OH)(piv)8(dea)2(MeOH)2(H2O)2](NO3)·H2O (1) (where Hpiv = pivalic acid) was prepared from the reaction of Mn(piv)2with Dy(NO3)3·6H2O and diethanolamine (H2dea) in a MeOH/CH2Cl2mixture. The C2-symmetric cluster comprises an unprecedented {Mn6IIIMnIVDy2III}28+core consisting of two distorted {Mn2IIIMnIVDyIIIO4} cubane moieties sharing a common MnIVvertex and decorated with two additional MnIIIatoms. Hirshfeld surface analysis and fingerprint plots are used for decoding the intermolecular interactions in 1. Magnetic studies indicate that 1exhibits a slow relaxation behavior with an effective energy barrier of 15.2 K and τ0= 1.4 × 10–7s.

Four neutral metal–organic frameworks (MOFs) {[Zn(bpdc)(3-bpmhz)]·1.5(dmf)}nMRT-1(1), {[Zn(bpdc)(3-bpmhz)]·(dmf)·0.5(Py)}nMRT-2(2), {[Zn(bpdc)(4-bpmhz)](MeOH)·0.5(H2O)}nMRT-3(3), and {[Cd(bpdc)(bda4bPy)]·2.5(dmf)}nMRT-4(4) (where MRTstands for the Moldova Research Team), along with a one-dimensional coordination polymer {[Zn(Hbpdc)2(3-bphz)(MeOH)2]·2(dmf)}n(5), a binuclear complex [Cd2(bpdc)2(3-bpmhz)(H2O)6] (6), and a two-dimensional coordination polymer {[Cd(bpdc)(dmso)(H2O)]·0.25(H2bpdc)}n(7), were obtained from blends of 4,4′-biphenyldicarboxylic acid (H2bpdc) with 1,2-bis(1-(pyridin-3-yl)ethylidene)hydrazine (3-bpmhz), 1,2-bis(pyridin-3-ylmethylene)hydrazine (3-bphz), 1,2-bis(1-(pyridin-4-yl)ethylidene)hydrazine (4-bpmhz), or N1,N4-bis(pyridin-4-ylmethylene)-benzene-1,4-diamine (bda4bPy). MOFs 1and 2are supramolecular isomers. MOF 1is built on a single tetrahedral Zn(II) atom giving rise to a diamondoid (dia) coordination network with threefold interpenetration. MOFs 2–4represent a reticular series of primitive cubic (pcu) networks that originated from [M2(CO2)4] (M = Zn and Cd) secondary building units where the metal-carboxylate coordination layers are interlinked by azine double pillars. MOFs 2and 4reveal the twofold interpenetrations, while MOF 3reveals threefold interpenetration. Thermal analysis of MOFs 1–4carried out in the air and nitrogen atmospheres indicated their thermal stability. MOFs 1and 4had the solvent-accessible volumes of 30.1 and 43.7%, respectively. MOF 4demonstrated an efficient solvent exchange with the nitrobenzene (nb) capture registered by spectroscopic methods and confirmed by X-ray single-crystal studies for the crystal {[Cd(bpdc)(bda4bPy)]·1.5(nb)}n(4-nb). All compounds reveal ligand-based photoluminescence properties registered in the blue and green regions of the visible spectrum for 1–3and 5–7. The most porous MOF 4emitted very near to the standard white light and in the orange region when loaded with nb. The symmetry-adapted perturbation theory showed advantages of azine-functionalized pores in the studied MOFs for efficient capture of CO2molecules on the pores’ walls.

Optical computing with optical transistors has emerged as a possible solution to the exponentially growing computational workloads, yet an on-chip nano-optical modulation remains a challenge due to the intrinsically noninteracting nature of photons in addition to the diffraction limit. Here, we present an all-optical approach toward nano-excitonic transistors using an atomically thin WSe2/Mo0.5W0.5Se2heterobilayer inside a plasmonic tip-based nanocavity. Through optical wavefront shaping, we selectively modulate tip-enhanced photoluminescence (TEPL) responses of intra- and interlayer excitons in a ∼25 nm2area, demonstrating the enabling concept of an ultrathin 2-bit nano-excitonic transistor. We suggest a simple theoretical model describing the underlying adaptive TEPL modulation mechanism, which relies on the additional spatial degree of freedom provided by the presence of the plasmonic tip. Furthermore, we experimentally demonstrate a concept of a 2-trit nano-excitonic transistor, which can provide a technical basis for processing the massive amounts of data generated by emerging artificial intelligence technologies.

The coordination cluster compound [CoIII2DyIII4(OH)2(ib)8(bdea)2(NO3)4(H2O)2]·2MeCN (1) self-assembles in a high-yield reaction of cobalt(II) isobutyrate (ib) with Dy(NO3)3·6H2O and N-butyldiethanolamine (H2bdea) in air. The Ci-symmetric {CoIII2DyIII4} core fragment features two {CoDy2(μ3-OH)} triangles, joined by one of their Dy sites via μ-O and μ-carboxylate bridges. This results in a flat zigzag metal skeleton, in contrast to previously reported hexanuclear {Co2Ln4(μ3-OH)2} clusters, namely, exhibiting a more condensed combination of two {CoLn2(μ3-OH)} triangles that form a Dy4rhombus. According to ac susceptibility measurements, this rearrangement in 1reduces quantum tunneling of the magnetization and hence pushes up the onset of pronounced out-of-phase signals at zero bias field to 14 K, a significant change vs the more condensed {Co2Dy4} structures. As intermolecular interactions between coordination clusters in the solid state are well-known to also influence SMM features, comparative Hirshfeld surface analyses are also presented.

ABSTRACT:This article provides new information about Ayn Rand's residences in Saint Petersburg (Petrograd/Leningrad). The authors, who based the article on hitherto unknown archival documents, discovered new information regarding the exact location of the apartments where the Rosenbaums lived in the city from 1904 through the 1930s. Furthermore, the article provides information about where Rand's grandparents, Berko (Boris) Kaplan and his wife Sarah, had been living. Additionally, it offers English translations and Russian originals of archival documents related to the aforementioned locations.

Most of the light from blazars, active galactic nuclei with jets of magnetized plasma that point nearly along the line of sight, is produced by high-energy particles, up to around 1 TeV. Although the jets are known to be ultimately powered by a supermassive black hole, how the particles are accelerated to such high energies has been an unanswered question. The process must be related to the magnetic field, which can be probed by observations of the polarization of light from the jets. Measurements of the radio to optical polarization—the only range available until now—probe extended regions of the jet containing particles that left the acceleration site days to years earlier1–3, and hence do not directly explore the acceleration mechanism, as could X-ray measurements. Here we report the detection of X-ray polarization from the blazar Markarian 501 (Mrk 501). We measure an X-ray linear polarization degree ΠXof around 10%, which is a factor of around 2 higher than the value at optical wavelengths, with a polarization angle parallel to the radio jet. This points to a shock front as the source of particle acceleration and also implies that the plasma becomes increasingly turbulent with distance from the shock.

Abstract: Layered nanoheterostructure Fe|MgO|Cr|MgO|Fe is an artificial ferromagnetic material in which exchange interaction of magnetic moments in the iron layers through intermediate dielectric and metal layers can lead to magnetic configurations which do not appear in well-studied systems Fe|MgO|Fe and Fe|Cr|Fe. In this work correlations of the structural and magnetic properties of layered nanoheterostructures Fe(10 nm)|MgO(1.5 nm)|Cr(tnm)|MgO(1.5 nm)|Fe(7 nm) (with the thickness tbeing 0.9 and 1.8 nm) were studied. Structural studies made using high-resolution X-ray diffractometry and reflectometry proved the formation of a texturized structure and revealed its prominent layered character with clear interfaces between the layers.

Abstract: The structure and magnetic properties of thin polycrystalline films of Co100 –xWx(0 ≤ x≤ 30) deposited by magnetron sputtering on glass substrates are investigated including those containing buffer layers of Ta, W, and Ru. It is found that films of pure Co are non-single-phase and contain hcp and fcc crystalline modifications. Doping leads to an increase in the concentration of the fcc phase and an enhancement of the texture of the (111) type, and subsequently to the amorphization of the films. The buffer layers influence to a certain extent on the depth and concentration localization of these transformations. A characteristic feature of the magnetism of Co–W films is a significant perpendicular component in the macroscopic magnetic anisotropy, which leads to a “supercritical” magnetic state. It is shown that its source is the textured fcc phase, the crystalline anisotropy of which is enhanced as a result of doping of cobalt with tungsten.

Interaction of mefenamic acid [2-(2,3-dimethylphenyl)aminobenzoic acid, maH] with piperazine (ppz), 1,4,7,10-tetraazacyclododecane (cyclen), meso-5,7,7,12,12,14-hexamethyl-1,4,8,11-tetraazacyclotetradecane (teta), and tris(hydroxymethyl)aminomethane (tris) resulted in crystalline proton-transfer complexes of the compositions (ppzH2)(ma)2·4H2O1, (cyclenH2)(ma)2·2H2O2, (tetaH2)(ma)2·2H2O3, and (trisH)(ma)·H2O4. Immediate cation−anion hydrogen bonds and those mediated by water molecules are the prime driving forces for the maH and amine assembly. Persistent CH···π interactions involving the aromatic rings were found to play an important role in the formation of final structures. All complexes reveal the pronounced segregation of hydrophilic and hydrophobic regions.

Clinical misdiagnosis between cutaneous squamous cell carcinoma (cSCC) and basal cell carcinoma (BCC) affects treatment plans. We report a tissue sampling approachwith molecular biopsy using electroporation. This method, coined e-biopsy, enables non-destructive non-thermal permeabilization of cells in the skin for vacuum-assisted extraction of biomolecules. We used e-biopsy for ex vivo proteome extraction from 3 locations per patient in 21 cSCC, 20 BCC and 7 actinic keratosis human skin samples. Using liquid chromatography mass spectrometry (LC/MS/MS),we identified 5,966 proteins observed with non-zero intensity in at least one samples. The intra-patient Pearson correlation of 0.888 ± 0.065 for BCC patients; 0.858 ± 0.077 for SCC patients; 0.876 ± 0.116 for solar actinic keratosis (AK)patients indicates high consistency of the e-biopsy sampling. The mass spectra presented significantly different proteome profiles for cSCC, BCC and AK, with several hundreds of proteins differentially expressed. Notably,our study showed that proteomes sampled with e-biopsy from cSCC and BCC lesions are different, and that proteins of CRNN, SULT1E1 and ITPK1 genes are significantly overexpressed in BCC in comparison to cSCC. Our results provide evidence that the e-biopsy approach could potentially be used as a tool to support cutaneous lesions classification with molecular pathology.

Abstract:This article discusses the construction of a Jewish aristocratic identity through art collecting and patronage, in parallel with other “aristocratic” activities and lifestyles. The focus is a particular Galican family ennobled by Franz Joseph I in 1881. The family’s ambitions and achievements are known from a memoir by Artur Lilien-Brzozdowiecki (1890, Lviv–1958, London), who was a great-great-grandson of the community head Rachmiel von Mises (1800–1891), a distant cousin of the artist Moses Ephraim Lilien (1874–1925), and a grandson of the banker Ignacy Lilien, who financed Moses Ephraim’s education. The article considers the self-construction of the family members as art connoisseurs and artists. These included the banker, industrialist, artist, and art collector Maurycy Nierenstein (1840–1917); painter Helene von Mises (1883–1942); architect Marya Lilien (1900–1998); and economist, lawyer, army officer, and collector Artur Lilien-Brzozdowiecki.

Starting from a well-known hexanuclear mixed-valent manganese cluster, we report a synthetic protocol for its extension toward very large 3d-4f clusters. The exemplary case study demonstrates that a combination of such {Mn6} clusters with a DyIIIsalt and an auxiliary triazine-type ligand yields a large bean-like, heterometallic dotriacontanuclear mixed-valent nanocluster [Mn26Dy6O16(OH)12(O2CCHMe2)42]. This compound, which possesses a molecular C2symmetry and crystallizes in a dense packing arrangement without inclusion of solvents, comprises 16 MnIII, 10 MnII, and 6 DyIIIions, thus leading to a plurality of intracluster magnetic exchange interactions. Interestingly, this results in the highest-nuclearity Mn–Dy cluster that shows a single-molecule magnetic (SMM) behavior.

With its linear energy dispersion and large transition dipole matrix element, graphene is an attractive material for nonlinear optoelectronic applications. However, the mechanistic origin of its strong nonlinear response, the ultrafast coherent dynamics and the associated nanoscale phenomena have remained elusive due to a lack of suitable experimental techniques. Here, using adiabatic nanofocusing and imaging, we study the broadband four-wave mixing (FWM) response of graphene with nanometre and femtosecond spatio-temporal resolution. We detect a nonlinear signal enhancement at the edges and dependence on the number of layers from excitation areas as small as 104carbon atoms. Femtosecond FWM nanoimaging and concomitant frequency-domain measurements reveal dephasing on T2≈ 6 ± 1 fs timescales, which we attribute to a strong electron–electron interaction. We also identify an unusual non-local FWM response on ~100–400 nm length scales, which we assign to a Doppler effect controlling the nonlinear interaction between the tip near-field momenta and the graphene electrons with high Fermi velocity. These results illustrate the distinct nonlinear nanooptical properties of graphene, expected also in related classes of two-dimensional materials, that could form the basis for improved nonlinear and ultrafast nanophotonic devices. Ultrafast nanoimaging reveals the origin of the nonlinear optical properties of graphene.

The possibility of using the laser fluorescence method for detecting leakage of oil pipelines at a fluorescence excitation wavelength of 355 nm was analyzed. The results of experimental studies of the spectra of laser-induced fluorescence of clean crude oils and crude oils spilled on the soil as well as natural and anthropogenic elements of the site naturally located on the land are presented. It is shown that the fluorescent signal from oil spills on the Earth’s surface can be compared with that from vegetation and water bodies. However, the fluorescent signal from oil spills can be distinguished from that from vegetation and water bodies by analyzing the shape of the fluorescence spectra.

Cyclic triimidazole (C9H6N6, L), with C3hmolecular symmetry and three nitrogen atoms available for coordination, is here successfully employed for the first time in the synthesis of coordination compounds. In particular, by varying the reaction conditions (e.g., solvent, temperature, template), seven Cu(I)-halide coordination polymers of different dimensionality are obtained: two 1D polymers, [CuIL]n(1) and {[CuIL]·(I2)0.5}n(2), three 2D nets, [CuXL]n(X = I, Br) (3–5), and two 3D networks, [CuClL]n(6) and {[Cu3L4]I3}n(7). Single crystal X-ray diffraction analysis reveals that the structural versatility of both the ligand and the CuX moiety allows isolating 1D double-stranded stairs in which Lis monodentate, 2D layers containing either Cu2(μ-X)2or Cu2(μ-X) moieties and bidentate Lligands, 3D frameworks built up by tridentate Llinkers and either monodentate or noncoordinating halogen atoms. The 3D frameworks show nets of srsand bortopologies. The SHG efficiency of powders of 7(the only noncentrosymmetric derivative of the series) is 10 times higher than that of sucrose. Phosphorescent emission of XLCT character is observed for 1and 6.

Abstract: The effect of structural properties on the formation of the perpendicular magnetic anisotropy in Co/Dy superlattices has been studied. The superlattices are found to be composition-modulated alloys in which, on the one hand, a rigid periodicity in thicknesses and compositions takes place and, on the other hand, the interdiffusion of Co and Dy at interlayer boundaries leads to a periodic change in the Co and Dy concentrations with depth. The perpendicular magnetic anisotropy in Co/Dy is shown to be due to the perpendicular orientation of the magnetization in CoDy alloy layers, while the magnetization of Co layers is oriented in the sample plane.

CloudKit is Apple's cloud backend service and application development framework that provides strongly-consistent storage for structured data and makes it easy to synchronize data across user devices or share it among multiple users. Launched more than 3 years ago, CloudKit forms the foundation for more than 50 Apple apps, including many of our most important and popular applications such as Photos, iCloud Drive, Notes, Keynote, and News, as well as many third-party apps. To deliver this at large scale, CloudKit explicitly leverages multi-tenancy at the application level as well as at the user level to guide efficient data placement and distribution. By using CloudKit application developers are free to focus on delivering the application front-end and logic while relying on CloudKit for scale, consistency, durability and security. CloudKit manages petabytes of data and handles hundreds of millions of users around the world on a daily basis.

We report on the composition of Er-doped KGd_xYb_yY_1−x−y(WO_4)_2 layers to be grown onto undoped KY(WO_4)_2 substrate providing fine lattice matching and high refractive index contrast with the substrate and fabrication of high optical quality Er(1.3  at. %):KGd_0.2Yb_0.15Y_0.65(WO_4)_2 epitaxial layers with thickness up to 180 μm. Absorption and luminescence properties of the layer were measured and laser action under direct in-band pumping was reported for the first time, to our knowledge, in a non-waveguide configuration. A maximum output power of 16 mW with slope efficiency of 64% was achieved at 1606 nm.

Systems that exhibit phase competition, order parameter coexistence, and emergent order parameter topologies constitute a major part of modern condensed-matter physics. Here, by applying a range of characterization techniques, and simulations, we observe that in PbTiO3/SrTiO3superlattices all of these effects can be found. By exploring superlattice period-, temperature- and field-dependent evolution of these structures, we observe several new features. First, it is possible to engineer phase coexistence mediated by a first-order phase transition between an emergent, low-temperature vortex phase with electric toroidal order and a high-temperature ferroelectric a1/a2phase. At room temperature, the coexisting vortex and ferroelectric phases form a mesoscale, fibre-textured hierarchical superstructure. The vortex phase possesses an axial polarization, set by the net polarization of the surrounding ferroelectric domains, such that it possesses a multi-order-parameter state and belongs to a class of gyrotropic electrotoroidal compounds. Finally, application of electric fields to this mixed-phase system permits interconversion between the vortex and the ferroelectric phases concomitant with order-of-magnitude changes in piezoelectric and nonlinear optical responses. Our findings suggest new cross-coupled functionalities.

Identification and dynamical attribution of multidecadal climate undulations to either variations in external forcings or to internal sources is one of the most important topics of modern climate science, especially in conjunction with the issue of human‐induced global warming. Here we utilize ensembles of twentieth century climate simulations to isolate the forced signal and residual internal variability in a network of observed and modeled climate indices. The observed internal variability so estimated exhibits a pronounced multidecadal mode with a distinctive spatiotemporal signature, which is altogether absent in model simulations. This single mode explains a major fraction of model‐data differences over the entire climate index network considered; it may reflect either biases in the models' forced response or models' lack of requisite internal dynamics, or a combination of both. Global and regional warming trends over the course of the twentieth century have been nonuniform, with decadal and longer periods of faster or slower warming, or even cooling. Here we show that state‐of‐the‐art global models used to predict climate fail to adequately reproduce such multidecadal climate variations. In particular, the models underestimate the magnitude of the observed variability and misrepresent its spatial pattern. Therefore, our ability to interpret the observed climate change using these models is limited. Estimated internal (unforced) variability in observations has a much larger magnitude versus that in CMIP5 modelsThe model‐data mismatch is dominated by a low‐order hemispheric multidecadal modeNone of the CMIP5 models is able to reproduce the spatiotemporal structure of the observed multidecadal variability

On the way to copper(I) iodide coordination polymers with specific luminescent properties, the in situ reduction of Cu(II) in the presence of KI and bidentate N-heteroatomic ligand, either pyrazine (pyz) or 4,4′-bipyridine (bpy), resulted in one two-dimensional and two three-dimensional new coordination networks. Starting from Cu(NO3)2·3H2O in the presence of pyz, successive precipitation of known yellow [(CuII)2(pyz)]n, new orange [CuII(pyz)]n, and new dark blue {[CuI(pyz)2]·I5}npolymeric solids was observed. Starting from the same salt in the presence of bpy resulted in the successive precipitation of known yellow [(CuII)2(bpy)]nand new brown {[CuII(NO3)(bpy)2]·I3·(dmf·H2O)}ncoordination polymers. By using either Cu(CH3COO)2·H2O or Cu(BF4)2as starting materials, both known forms, yellow [(CuII)2(bpy)]nand orange [CuII(bpy)]n, precipitated successively. The new solids were characterized by IR spectroscopy and X-ray analysis. [CuII(pyz)]nrepresents the missing member in the row of two-dimensional coordination networks with general formula [CuIX(pyz)]n(X = Cl, Br, I). Its steady state and time-resolved characterization together with DFT and TDDFT calculations revealed that the emission at room temperature is mainly delayed fluorescence originating from mixed singlet metal-to-ligand charge transfer and halide-to-ligand charge transfer states, while that at 77 K is phosphorescence, associated with the small singlet–triplet energy differences (ΔE= 70 meV).

New tetranuclear and octanuclear mixed-valent cobalt(II/III) pivalate clusters, namely, [NaCo4(O2CCMe3)6(HO2CCMe3)2(teaH)2(N3)]·2H2O (in two polymorphic modifications, 1and 1a) and [Co8(O2CCMe3)10(teaH)4(N3)](Me3CCO2)·MeCN·H2O (2) have been synthesized by ultrasonic treatment of a dinuclear cobalt(II) pivalate precursor with sodium azide and triethanolamine (teaH3) ligand in acetonitrile. The use of Dy(NO3)3·6H2O in a similar reaction led to the precipitation of a tetranuclear [NaCo4(O2CCMe3)4(teaH)2(N3)(NO3)2(H2O)2]·H2O (3) cluster and a heterometallic hexanuclear [Co3Dy3(OH)4(O2CCMe3)6(teaH)3(H2O)3](NO3)2·H2O (4) cluster. Single-crystal X-ray analysis showed that 1(1a) and 3consist of a tetranuclear pivalate/teaH3mixed-ligand cluster [CoII2CoIII2(O2CCMe3)4(teaH)2(N3)]+decorated with sodium pivalates [Na(O2CCMe3)2(HO2CCMe3)2]−(1or 1a) or sodium nitrates [Na(NO3)2]−(3) to form a square-pyramidal assembly. In 2, the cationic [Co8(O2CCMe3)10(teaH)4(N3)]+cluster comprises a mixed-valent {CoII4CoIII4} core encapsulated by an azide, 4 teaH2–alcoholamine ligands, and 10 bridging pivalates. Remarkably, in this core, the μ4-N3–ligand joins all four CoIIatoms. The heterometallic hexanuclear compound 4consists of a cationic [CoIII3DyIII3(OH)4(O2CCMe3)6(teaH)3(H2O)3]2+cluster, two NO3–anions, and a crystallization water molecule. The arrangement of metal atoms in 4can be approximated as the assembly of a smaller equilateral triangle defined by three Dy sites with a Dy···Dy distance of 3.9 Å and a larger triangle formed by Co sites [Co···Co, 6.1–6.2 Å]. The interpretation of the magnetic properties of clusters 2–4was performed in the framework of theoretical models, taking into account the structural peculiarities of clusters and their energy spectra. The behavior of clusters 2and 3containing CoIIions with orbitally nondegenerate ground states is determined by the zero-field splitting of these states and Heisenberg exchange interaction between the ions. To get a good understanding of the observed magnetic behavior of cluster 4, we take into consideration the crystal fields acting on the DyIIIions, the ferromagnetic coupling of neighboring DyIIIions, and the intercluster antiferromagnetic exchange. For all examined clusters, the developed models describe well the observed temperature dependence of the magnetic susceptibility and the field dependence of magnetization. The computational results apparently show that in cluster 4two DyIIIions with similar nearest surroundings demonstrate single-molecule-magnet (SMM) behavior, while the strong rhombicity of the ligand surrounding hinders the SMM behavior of the third DyIIIion.

A family of wheel-shaped charge-neutral heterometallic {FeIII4LnIII2}- and {FeIII18MIII6}-type coordination clusters demonstrates the intricate interplay of solvent effects and structure-directing roles of semiflexible bridging ligands. The {Fe4Ln2}-type compounds [Fe4Ln2(O2CCMe3)6(N3)4(Htea)4]·2(EtOH), Ln = Dy (1a), Er (1b), Ho (1c); [Fe4Tb2(O2CCMe3)6(N3)4(Htea)4] (1d); [Fe4Ln2(O2CCMe3)6(N3)4(Htea)4]·2(CH2Cl2), Ln = Dy (2a), Er (2b); [Fe4Ln2(O2CCMe3)4(N3)6(Htea)4]·2(EtOH)·2(CH2Cl2), Ln = Dy (3a), Er (3b) and the {Fe18M6}-type compounds [Fe18M6(O2CCHMe2)12(Htea)18(tea)6(N3)6]·n(solvent), M = Dy (4, 4a), Gd (5), Tb (6), Ho (7), Sm (8), Eu (9), and Y (10) form in ca. 20–40% yields in direct reaction of trinuclear FeIIIpivalate or isobutyrate clusters, lanthanide/yttrium nitrates, and bridging triethanolamine (H3tea) and azide ligands in different solvents: EtOH for the smaller {Fe4Ln2} wheels and MeOH/MeCN or MeOH/EtOH for the larger {Fe18M6} wheels. Single-crystal X-ray diffraction analyses revealed that 1–3consist of planar centrosymmetric hexanuclear clusters built from FeIIIand LnIIIions linked by an array of bridging carboxylate, azide, and aminopolyalcoholato-based ligands into a cyclic structure with a cavity, and with distinct sets of crystal solvents (2 EtOH per formula unit in 1a–c, 2 CH2Cl2in 2, and 2 EtOH and 2 CH2Cl2in 3). In 4–10, the largest 3d/4f wheels currently known, nearly linear Fe3fragments are joined via mononuclear Ln/Y units by a set of isobutyrates and amino alcohol ligands into virtually planar rings. The magnetic properties of 1–10reveal slow magnetization relaxation for {Fe4Tb2} (1d) and slow relaxation for {Fe4Ho2} (1c), {Fe18Dy6} (4), and {Fe18Tb6} (6).

AimsThe distinction between benign and malignant thyroid nodules has important therapeutic implications. Our objective was to develop an assay that could classify indeterminate thyroid nodules as benign or suspicious, using routinely prepared fine needle aspirate (FNA) cytology smears.MethodsA training set of 375 FNA smears was used to develop the microRNA-based assay, which was validated using a blinded, multicentre, retrospective cohort of 201 smears. Final diagnosis of the validation samples was determined based on corresponding surgical specimens, reviewed by the contributing institute pathologist and two independent pathologists. Validation samples were from adult patients (≥18 years) with nodule size >0.5 cm, and a final diagnosis confirmed by at least one of the two blinded, independent pathologists. The developed assay, RosettaGX Reveal, differentiates benign from malignant thyroid nodules, using quantitative RT-PCR.ResultsTest performance on the 189 samples that passed quality control: negative predictive value: 91% (95% CI 84% to 96%); sensitivity: 85% (CI 74% to 93%); specificity: 72% (CI 63% to 79%). Performance for cases in which all three reviewing pathologists were in agreement regarding the final diagnosis (n=150): negative predictive value: 99% (CI 94% to 100%); sensitivity: 98% (CI 87% to 100%); specificity: 78% (CI 69% to 85%).ConclusionsA novel assay utilising microRNA expression in cytology smears was developed. The assay distinguishes benign from malignant thyroid nodules using a single FNA stained smear, and does not require fresh tissue or special collection and shipment conditions. This assay offers a valuable tool for the preoperative classification of thyroid samples with indeterminate cytology.

Transition-metal dichalcogenides (TMDs) have demonstrated a wide range of novel photonic, optoelectronic, and correlated electron phenomena for more than a decade. However, the coherent dynamics of their excitons, including possibly long dephasing times and their sensitivity to spatial heterogeneities, are still poorly understood. Here we implement adiabatic plasmonic nanofocused four-wave mixing (FWM) to image the coherent electron dynamics in monolayer WSe2. We observe nanoscale heterogeneities at room temperature with dephasing ranging from T2≲ 5 to T2≳ 60 fs on length scales of 50–100 nm. We further observe a counterintuitive anticorrelation between FWM intensity and T2, with the weakest FWM emission at locations of longest coherence. We interpret this behavior as a nonlocal nano-optical interplay between spatial coherence of the nonlinear polarization and disorder-induced scattering. The results highlight the challenges associated with heterogeneities in TMDs limiting their photophysical properties, yet also the potential of their novel nonlinear optical phenomena.

Aims. This paper aims at further studying one of the nearby Galactic globular clusters (GCs), NGC 3201. It is known to experience notable irregular variability of reddening across its face. By relying on our previous studies and findings and by developing them, we focus on the brighter sequences of the color-magnitude diagram (CMD) and on the cluster's characteristics.

Aims.We carry out and analyze new multi-color photometry of the Galactic globular cluster (GC) M 75 in $\it UBVI$and focus on the brighter sequences of the color–magnitude diagram (CMD), with particular emphasis on their location in U-based CMD. Specifically, we study the level both of the horizontal (HB) and red giant branches (RGB) relative to the main-sequence turnoff (TO) in the Umagnitude.

We present first measurements of the pseudorapidity and azimuth (η, φ) bin-size dependence of event-wise mean transverse-momentum 〈pt〉 fluctuations for Au–Au collisions at GeV. We invert that dependence to obtain pt autocorrelations on differences (ηΔ, φΔ) interpreted to represent velocity/temperature distributions on (η, φ). The general form of the autocorrelations suggests that the basic correlation mechanism is parton fragmentation. The autocorrelations vary rapidly with collision centrality, which suggests that fragmentation is strongly modified by a dissipative medium in the more central Au–Au collisions relative to peripheral or p–p collisions.

Femtosecond nonlinear optical imaging with nanoscale spatial resolution would provide access to coupled degrees of freedom and ultrafast response functions on the characteristic length scales of electronic and vibrational excitations. Although near-field microscopy provides the desired spatial resolution, the design of a broadband high-contrast nanoprobe for ultrafast temporal resolution is challenging due to the inherently weak nonlinear optical signals generated in subwavelength volumes. Here, we demonstrate broadband four-wave mixing with enhanced nonlinear frequency conversion efficiency at the apex of a nanometre conical tip. Far-field light is coupled through a grating at the shaft of the tip, generating plasmons that propagate to the apex while undergoing asymptotic compression and amplification, resulting in a nonlinear conversion efficiency of up to 1 × 10–5. We apply this nonlinear nanoprobe to image the few-femtosecond coherent dynamics of plasmonic hotspots on a nanostructured gold surface with spatial resolution of a few tens of nanometres. The approach can be generalized towards spatiotemporal imaging and control of coherent dynamics on the nanoscale, including the extension to multidimensional spectroscopy and imaging.

A heterometallic hexanuclear mixed-valence Co–Dy cluster [Co4Dy2(OH)2(O2CCMe3)8(HO2CCMe3)2(teaH)2(N3)2]·2(EtOH) (1) has been prepared from the reaction of dinuclear Co(II) pivalate with triethanolamine and azide ligands and characterized by elemental analysis, IR spectroscopy, and X-ray crystallography. The metal atoms in the {CoII2CoIII2DyIII2} cluster core are bridged by two μ3-hydroxy groups, two azide N3–anions, six pivalate residues, and two doubly deprotonated teaH2–ligands. A theoretical model has been developed to explain the magnetic behavior of 1. The model takes into account the crystal fields acting on the DyIIIions and the anti- and ferromagnetic exchange interactions in the pairs Co–Dy and Co–Co, respectively. The Stark structure for the DyIIIions is calculated with due account of the covalence effects within the frames of the exchange charge model of the crystal field. It is demonstrated that at low temperatures the magnetic properties of the cluster are determined by the interaction of the ground state Kramers doublet of the CoIIion with those Stark levels of the DyIIIions, for which the energies are smaller than the spin–orbital coupling parameter. At higher temperatures, the population of the CoIIion multiplets with the angular momentum values 3/2 and 5/2 leads to the increase of the magnetic susceptibility. The observed temperature dependence of the χMTproduct and field dependence of the magnetization are satisfactorily explained within the framework of the suggested model.

We suggest that the majority of the “young”, so–called “second parameter” globular clusters (SPGCs) have originated in the outer Galactic halo due to a process other than a tidal disruption of the dwarf spheroidal (dSph) galaxies. Basic observational evidence regarding both the dSphs and the SPGCs, coupled with the latest data about a rather large relative number of such clusters among globulars in M 33 and their low portion in M 31, seems to be consistent with the suspected process. It might have taken place within the system of the most massive galaxies of the Local Group (LG) at the earliest stages of their formation and evolution. We argue that the origin and basic characteristics of the SPGCs can naturally be explained as a result of mass outflow from M 31, during and due to formation of its Pop. II stars, and subsequent accretion of gas onto its massive companions, the Galaxy and M 33. An amount of the gas accreted onto the Milky Way is expected to have been quite enough for the formation in the outer Galactic halo not only of the clusters under consideration but also a number of those dSph galaxies which are as young as the SPGCs. A less significant, but notable mass transfer from the starbursting protoGalaxy to the massive members of the LG might have occurred, too.