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The potassium hexacyanoferrate(III), K3[FeIII(CN)6], is known for its exceptional magnetic anisotropy among the 3d transition metal series. The Fe(III) ions are in the S= 1/2 low spin state imposed by the strong crystal field of the cyanido ligands. A large orbital magnetic moment is expected from previous publications. In the present work, X-ray magnetic circular dichroism was recorded for a powder sample, allowing direct measurement of the Fe(III) orbital magnetic moment. A combination of molecular multiconfigurational ab initio and atomic ligand field multiplets calculations provides the spin and orbital magnetic moments for the [FeIII(CN)6]3−isolated cluster, the crystallographic unit cell, and the powder sample. The calculations of the angular dependencies of the spin and orbital magnetic moments with the external magnetic induction direction reveal easy magnetization axes for each S= 1/2 molecular entity and the crystal. It also shows that the orbital magnetic moment dominates the spin magnetic moment for all directions. Our measurements confirm that the orbital magnetic moment contributes to 60% of the total magnetization for the powder, which is in excellent agreement with our theoretical predictions. An orbital magnetic moment greater than the spin magnetic moment is exceptional for 3d transition metal ions. The impact of crystal field strength and distortion, π back-bonding, spin–orbit coupling, and external magnetic induction was analyzed, leading to a deeper understanding of the spin and orbital magnetic anisotropies.

•High visceral fat volume is associated with better outcome in patients receiving first-line bevacizumab-based chemotherapy for metastatic colorectal cancer.•Visceral adipose burden could play a critical role in pharmacodynamics of bevacizumab.•Fat mass evaluation might serve to provide information for predicting therapeutic efficacy to VEGF-targeted therapy in patient with metastatic colorectal cancer.

CoFe Prussian blue analogues (PBAs) are well-known for their magnetic bistability tuned by external stimuli. The photoswitching properties are due to the electron transfer from CoLSIII-NC-FeLSIIto CoHSII-NC-FeLSIIIlinkage, accompanied by the spin change of the Co ions (HS stands for high spin and LS for low spin). In this work, we investigated 100 nm particles of the Rb2Co4[Fe(CN)6]3.3·11H2O PBA (named RbCoFe). The photoexcited state of the PBA was reached by red laser excitation (λ = 635 nm) and observed by X-ray absorption spectroscopy and X-ray magnetic circular dichroism (XMCD) that are element-specific probes. The XMCD measurements at the Co and Fe L2,3edges, probing the magnetic 3d orbitals, have provided a direct evidence of the antiferromagnetic interaction between the CoHSIIand the FeLSIIIions belonging to the core of the particles, thus confirming the previously published, though indirect XMCD measurements at Kedges. Because of the surface sensitivity of XMCD at the L2,3edges, the magnetic properties of the particle surface were also revealed. Surface CoHSII-FeLSIIIpairs exhibit a weak ferromagnetic interaction. Thus, the magnetic structure of the photomagnetic RbCoFe100 nm particles can be described as a ferrimagnetic core surrounded by a ferromagnetic shell. This finding brings new insights into the understanding of the complex magnetic properties of photoexcited RbCoFeand shows that the surface can have different magnetic behavior than the core. This should impact the nature of magnetic coupling in nanoparticles of CoFe PBA, where surface effect will dominate.

L’entretien postnatal précoce est une étape obligatoire du suivi après la naissance en France. Il vise à dépister et prévenir les troubles psychiques du post-partum. Les sages-femmes le réalisent entre la quatrième et la huitième semaine après l’accouchement, en explorant diverses thématiques. Il favorise le dialogue, l’orientation ainsi que le soutien des femmes et de leur famille.

Prussian blue analogues (PBAs) and derivatives have been extensively studied for the wide variety of their properties (magnetic, optical, electrochemical, thermal, ...), and slight structural distortions have been repeatedly called on in order to explain them. Variable pressure X-ray magnetic circular dichroism (XMCD) at the Ni and Fe K-edges of a series of four NiFe PBAs (CxNi4[Fe(CN)6](8+x)/3·nH2O (x= 0, 1, 2 for C = Cs and x= 2 for C = Rb)) at 10 K over the 0–7 GPa pressure range was used here to get new insights into these slight structural distortions. XMCD signals have been found to exhibit a high sensitivity to slight structural distortions and to offer promising perspectives for their quantifications. Furthermore, XMCD signals at the transition metal K-edges are not yet well understood and PBAs appear as particularly well-suited model compounds in order to disentangle the components at the origin of these XMCD signals. The pressure dependence of the XMCD signals can be qualitatively explained in terms of 3d–4p and 4p–4p orbital overlapping changes and symmetry change of the transition metal sites. Therefore, this work also shed new light on exchange interactions between 3d localized and 4p delocalized electrons as well as on the interpretation of XMCD signals at the TM K-edges.

Recently we conceived of an original strategy that allows the precipitation of Prussian blue analogues (PBAs) in the ordered pores of silica monoliths to lead to photomagnetic CoFe PBA–silica nanocomposites. To determine the critical parameters and fully control the synthesis of the photoactive CoFe PBA in the pores of the silica matrix, X‐ray absorption spectroscopy was performed at the cobalt K‐edge. This study showed that cobalt cation chemistry is the keystone of the entire process. The local environment and the electronic structure of the cobalt cation undergo several modifications during the formation process: first the incorporation of the cation as an octahedral complex into the ordered block copolymer phase, then the deprotonation by thermohydrolysis to give a fourfold‐coordinated deprotonated lowly condensed species and finally the formation of the 3D coordination network of CoFe PBA in acidic conditions through a rapid reprotonation followed by nucleophilic substitution accompanied by the electronic transfer, thus leading to the photomagnetic CoIII(LS)–FeII(LS) (LS=low spin) pairs.

Energy dispersive X-ray diffraction and X-ray absorption spectra of two CoFe Prussian blue analogues were collected under variable pressure at room temperature: one of them is essentially composed of Co IIand Fe IIIions and undergoes a Co II−Fe III→ Co III−Fe IIpressure-induced electron transfer, whereas the other is essentially composed of Co IIIand Fe IIions whatever the pressure. In both compounds, the Co III−Fe IIphase undergoes a structural distortion upon compression. The alkali cation free CoFe Prussian blue analogue, in which the pressure-induced electron transfer occurs, exhibits a more complicated interplay between structural and electronic events. Key interatomic interactions are proposed to account for the pressure behavior of both Co III−Fe IIand Co II−Fe IIIphases.

An original strategy is proposed to minimize the impact of respiratory motion on hepatic contrast-enhanced ultrasound studies. It is based on the a posteriori triggering of dynamic image sequences. It was tested on perfusion studies acquired with a high temporal resolution (8 images s−1) to enable parametric imaging. A respiratory component was first estimated by independent component analysis. The estimation of the local minima and maxima of this curve enabled us to select two subsets of frames, corresponding to the end-of-inspiration plane and to the end-of-expiration plane. Both subsets were simultaneously analysed using factor analysis of medical image sequences. This method identified the main contrast uptake kinetics and their associated localizations. The global strategy was validated firstly on a simulated study and then applied to 11 patients' studies. In both cases, the frame selection was judged relevant and a necessary preliminary step before applying methods of parametric imaging. In conclusion, the a posteriori gating method that is proposed is a first step towards local quantification of hepatic contrast-enhanced ultrasound studies.

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Primary cutaneous lymphomas have been successfully treated with interferons (IFNs), counterbalancing the T-helper 2 (Th2)-skewing state. We undertook a phase 1, open-label, dose-escalating trial of repeated intratumoral administration of TG1042 in patients with advanced primary cutaneous T-cell lymphomas (CTCLs) and multilesional cutaneous B-cell lymphomas (CBCLs). TG1042 is a third-generation, nonreplicating human adenovirus vector containing a human IFN-γ cDNA insert. Nine patients (7 CTCL, 2 CBCL) were enrolled at the following TG1042 doses: 3 × 109, 3 × 1010, and 3 × 1011 total particles. Local clinical response was observed in 5 of 9 treated patients (3 patients with complete response [CR] and 2 patients with partial response [PR]). Out of these, 3 patients showed systemic CR with the clearance of other noninjected skin lesions. Clinical response lasted for a median of 3 months (range, 1-6 months). Adverse events were mostly of grades 1 and 2. Seven of 9 treated patients had a detectable TG1042-derived IFN-γ message in injected lesions after the first treatment cycle. A TG1042-IFN-γ message was also detectable after several treatment cycles. We demonstrate the induction of humoral immune response to lymphoma tumor-antigen se70-2 after treatment. Our study shows that intralesional injections of TG1042 are both safe and well tolerated. (Blood. 2004;104:1631-1638)

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We describe various molecular switching processes occurring in several types of inorganic solids: spin cross-over (SC) compounds, photomagnetic Prussian blue analogs (PBAs), and valence-tautomeric system. Their thermo-, photo-, piezo-, and magneto-chromic properties are illustrated by recent examples. A common description of their static properties by a two-level model is given.

We report on recent progress in the control of dilution of photo-induced magnetic structures, by using thermal activation of the steric relaxation of the photo-excited electronic state. Experimental data relative to Rb- and Cs- based Prussian Blue Analogues are reported in terms of dynamic phase diagrams: Curie temperature vs concentration in photo-excited species. The building-up of correlations, due to steric interactions during the thermal relaxation process, is discussed. photomagnetism relaxation diluted magnetic systems

Abstract: A generic feature of photo-induced magnetic structures is reported, on the example of the photo-magnetic Prussian Blue analogues C x Co[Fe(CN)6] y , zH2O (C=Rb, Cs): the magnetic metastability of the “raw photo induced” (RPI) state obtained at low temperatures (below T C) and in low magnetic fields (below H C). The RPI state is characterised by a non-relaxed domain structure, due to the lack of thermal fluctuations during the building process of the ferrimagnetic domains. It evolves irreversibly under the effect of temperature or magnetic field. Some insight is given into the building mechanism of the RPI state, by consideration of the progressive increase of the Curie temperature.

We report on the photo-magnetic Prussian blue analogue series CsxCo[Fe(CN)6]y (Cs-PBA). They undergo both a valence tautomeric conversion at high temperature (∼250 K) and a photo-excitation at low temperature, according to the equation already established for K-PBA and Rb-PBA series: FeII+CoIII(LS)→FeIII+CoII(HS). The high-temperature state can be trapped by thermal quenching. The photo-magnetic data are not analysed quantitatively because of the strong effects of bulk absorption of light. However, the quantitative investigation could be completed by diffuse reflectivity, which only probes the top (=photo-excited) layers of the sample. We thus observed: (i) the bleaching effect of the photo-process, due to the weakening of the charge-transfer band in the red and near IR; (ii) the complete character of the photo-transformation, compared to the spontaneous tautomeric conversion; (iii) the similitude between the photo-excited and the high-temperature states, deduced from the comparison of absorption spectra and relaxation kinetics.

Appealing generic features of photo-induced magnetic structures are illustrated on the example of the Prussian Blue analogue Rb0.52Co[Fe(CN)6]0.84, 2.31H2O: (i) the ability of controlling by light the concentration in magnetic moments. This is conveniently achieved by combining an initial complete photo-transformation of the material, and various subsequent thermal annealings in the range 80–100 K. The dilution phase diagram of the ferrimagnetic system is, for the first time, derived. (ii) The magnetic metastability of the ‘raw photo-induced’ (RPI) state obtained at low temperatures (below Tc) and in low magnetic fields (below Hc). The RPI state is characterised by a non-relaxed domain structure, due to the lack of thermal fluctuations during the building process of the ferrimagnetic domains. It evolves irreversibly under the effect of temperature or magnetic field. The thermal aging properties of the RPI state are characterised.

Let D be a totally ordered set. Call an n -block, a Cartesian product of n closed and possibly empty intervals of D. Let sort be the set of all 2n -tuples of elements of D of the form (x1,...,x2n) , where (xn+1,...,x2n) is the n -tuple obtained by sorting the elements of the n -tuple (x1,...,xn) in non-decreasing order. We present and justify an algorithm of complexity O(n log n) which, given a 2n -block a , computes a 2n -block which, by inclusion, is the smallest block containing the set sort a . We show that this complexity is optimal.

Two series of Prussian blue analogs (PBA) were used as model compounds in order to disentangle the information contained in X-ray magnetic circular dichroism (XMCD) at the K-edges of transition metals. The number of 3d electrons on one site of the bimetallic cyanide polymer has been varied by associating to the [Fe(CN)6]3–or the [Cr(CN)6]3–precursors various divalent metal ions A2+(Mn2+, Fe2+, Co2+, Ni2+, and Cu2+). The compounds were studied by X-ray diffraction and SQUID magnetometry, as well as by X-ray absorption spectroscopy and XMCD at the K-edges of the A2+transition metal ion. The study shows that the 1s → 4p contribution to the A K-edge XMCD signal can be related to the electronic structure and the magnetic behavior of the probed A2+ion: the shape of the signal to the filling of the 3d orbitals, the sign of the signal to the direction of the magnetic moment with respect to the applied magnetic field, the intensity of the signal to the total spin number SA, and the area under curve to the Curie constant CA. The whole study hence demonstrates that PBAs are particularly well-adapted for understanding the information contained in the transition metals K-edge XMCD signals. It also offers new perspectives toward the full disentangling of the information contained in these signals and access to new insights into materials magnetic properties.