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Thin films of the spin-crossover (SCO) molecule Fe{[Me2Pyrz]3BH}2 (Fe-pyrz) were sublimed on Si/SiO2 and quartz substrates, and their properties investigated by X-ray absorption and photoemission spectroscopies, optical absorption, atomic force microscopy, and superconducting quantum interference device. Contrary to the previously studied Fe(phen)2(NCS)2, the films are not smooth but granular. The thin films qualitatively retain the typical SCO properties of the powder sample (SCO, thermal hysteresis, soft X-ray induced excited spin-state trapping, and light induced excited spin-state trapping) but present intriguing variations even in micrometer-thick films: the transition temperature decreases when the thickness is decreased, and the hysteresis is affected. We explain this behavior in the light of recent studies focusing on the role of surface energy in the thermodynamics of the spin transition in nano-structures. In the high-spin state at room temperature, the films have a large optical gap (~5 eV), decreasing at thickness below 50 nm, possibly due to film morphology. [ABSTRACT FROM AUTHOR]

Abstract: The organic spinterface describes the spin‐polarized properties that develop, due to charge transfer, at the interface between a ferromagnetic metal (FM) and the molecules of an organic semiconductor. However, assembling this interface may degrade the properties of its constituents. To circumvent this issue, one can separate the molecular and FM films using a less reactive nonmagnetic metal (NM). Spin‐resolved photoemission spectroscopy measurements on the prototypical system Co(001)//Cu/Mn‐phthalocyanine (MnPc) reveal at room temperature a high spin polarization P of the Cu/MnPc spinterface atop ferromagnetic Co. Surprisingly, it is found that the Cu thickness dependence of P remains essentially constant up to 10 monolayers (ML), which is inconsistent with the description of indirect exchange coupling between the Co layer and the molecule's Mn site. Ab initio calculations account for this fundamental discrepancy by showing that the topmost Cu layer before MnPc adsorption is already significantly spin‐polarized, and contributes to the formation of the Cu/MnPc spinterface atop Co. The results open a route toward 1) integrating electronically fragile molecules within organic spinterfaces and 2) electrically manipulating molecular spin chains using the well‐documented spin‐transfer torque properties of the FM/NM bilayer. [ABSTRACT FROM AUTHOR]

The design and the first experiments are described of a versatile cryogenic insert used for its electrical transport capabilities. The insert is designed for the cryomagnet installed on the DEIMOS beamline at the SOLEIL synchrotron dedicated to magnetic characterizations through X-ray absorption spectroscopy (XAS) measurements. This development was spurred by the multifunctional properties of novel materials such as multiferroics, in which, for example, the magnetic and electrical orders are intertwined and may be probed using XAS. The insert thus enables XAS to in situ probe this interplay. The implementation of redundant wiring and careful shielding also enables studies on operating electronic devices. Measurements on magnetic tunnel junctions illustrate the potential of the equipment toward XAS studies of in operando electronic devices. [ABSTRACT FROM AUTHOR]

There is eternal discussion on the best surgical method of pancreatoduodenectomy and reconstruction method. Several different methods of pancreatic stump anastomosis exist. The most popular argument taken into account in the discussion is the frequency of early postoperative complications. Relatively fewer papers analyse the late functional outcome of pancreatic surgery and the method of anastomosis employed. Authors presented short series of 12 patients after pancreatic surgery with analysis of pancreatic remnant morphology and function. Pancreatic remnant volume, pancreatic duct distension and stool elastase-1 test were analysed. There was no correlation of pancreatic exo- or endocrine insufficiency with the volume of pancreatic remnant or the kind of surgery or anastomosis performed. [ABSTRACT FROM AUTHOR]

The aim of the study was to evaluate the role of MR urography (MRU) in the diagnosis of obstructive uropathy in selected groups of patients. The groups involved following pathologies: calculi; strictures of ureteropelvic junction (UPJ); benign and malignancy-induced ureterostenosis. Sixty patients with clinical diagnosis of obstructive uropathy were subjected to static fluid MRU (sMRU) with the use of 3D turbo spin echo (TSE) sequence in a 0.5-T magnet. The examination was completed with conventional MR sequences and in 12 cases additionally with sequences after the administration of Gd-DTPA and excretory MRU. The results were compared with intravenous urography (IVU), CT, US, clinical and histopathological data. The degree of the urinary tract dilatation as well as the level and type of obstruction were estimated. In patients with urolithiasis sMRU correctly depicted the degree of ureterohydronephrosis in 85%, in cases of UPJ stenosis and malignancy-induced ureterostenosis in 100% and in the group of benign ureterostenosis in 91% of patients. Determination of obstruction level in patients with stones was adequate in 92% and in cases of non-calculous ureteral strictures in 100% of patients. The sMRU sequence alone could not specify the nature of obstruction except 1 case of bladder carcinoma. Filling defects in ureters visible on MR urograms were verified with IVU or CT to exclude intrinsic tumours. Completed with conventional MR sequences sMRU enabled the depiction of solid mass or infiltration in 83% cases of malignancy-induced ureterostenosis, and in the remaining groups of patients neoplastic process was excluded in 91%. In conjunction with excretory MRU and conventional MR images sMRU appears to be a highly useful technique in assessment of obstructive uropathy, especially that of non-calculous origin. Among different clinical applications MRU is superior in the evaluation of dilated urinary tract in altered anatomical conditions (e.g. in patients with ileal neobladder). [ABSTRACT FROM AUTHOR]

The value of MRI in assessing pancreatic transplants was studied in 37 patients. Sixty-seven MRI examinations were performed in patients with an uncomplicated transplant, a4 in patients with poorly functioning gransplant, and 10 in patients with a non-functioning graft. On the basis of 54 follow-up studies, it was shown that the volume of the graft decreased systematically during the 8 months after transplantation. On T1-weighted images the normal transplant was poorly delineated, with an almost homogeneous isointense or slightly hyperintense structure when compared with either renal transplant cortex or muscle. On T2-weighted images the organ was isointense or slightly hypointense compared with fat and hyperintense compared with muscle. T2-weighted delayed echo time image (TR = 2000 ms, TE = 150-200 ms) showed transplanted pancreas as well-delineated, hypointense and with a lobulated structure. This structure was characteristic of normal whole pancreatic grafts. Patent transplant vessels were seen as tubular structures of low signal intensity on T2-weighted short echo time images (TR = 2000 ms, TE = 50 ms). In the 10 patients with a non-functioning pancreatic transplant there were: 4 cases of focal intraparenchymal abnormalities, 6 cases in which the lobular structure was absent, and 4 cases of absence of patent graft main vessels (3 thromboses). There was no configuration of signal intensity of pancreatic parenchyma on MRI which could be considered typical for normal or non-functioning transplant. [ABSTRACT FROM AUTHOR]