Impact of dual-layer solid-electrolyte interphase inhomogeneities on early-stage defect formation in Si electrodes.

While intensive efforts have been devoted to studying the nature of the solid-electrolyte interphase (SEI), little attention has been paid to understanding its role in the mechanical failures of electrodes. Here we unveil the impact of SEI inhomogeneities on early-stage defect formation in Si electrodes. Buried under the SEI, these early-stage defects are inaccessible by most surface-probing techniques. With operando full field diffraction X-ray microscopy, we observe the formation of these defects in real time and connect their origin to a heterogeneous degree of lithiation. This heterogeneous lithiation is further correlated to inhomogeneities in topography and lithium-ion mobility in both the inner- and outer-SEI, thanks to a combination of operando atomic force microscopy, electrochemical strain microscopy and sputter-etched X-ray photoelectron spectroscopy. Our multi-modal study bridges observations across the multi-level interfaces (Si/LixSi/inner-SEI/outer-SEI), thus offering novel insights into the impact of SEI homogeneities on the structural stability of Si-based lithium-ion batteries.

Experimental evidence for the relaxation coupling of all longitudinal 7Li magnetization orders in the superionic conductor Li10GeP2S12.

This contribution addresses the experimental proof of the relaxation coupling of the 7Li (I = 3/2) longitudinal magnetization orders in the solid-state electrolyte Li10GeP2S12 (LGPS). This effect was theoretically described by Korb and Petit in 1988 but has not yet been shown experimentally. In a 2D-T1/spin-alignment echo (SAE) experiment, the inverse Laplace transformation of the spectral component over two time dimensions revealed the asymmetric course of the spin-lattice relaxation following from the coupling of all longitudinal orders. These observations were supported by Multi-quantum-filter experiments and by simulations of the 2D-T1/SAE experiment with a lithium spin system. Since the asymmetric relaxation effects are directly dependent on the velocities and degrees of freedom of ion motion they could be used especially in fast Li-ion conductors as a separation tool for environments with different mobility processes.

Chemical shift reference scale for Li solid state NMR derived by first-principles DFT calculations.

For studying electrode and electrolyte materials for lithium ion batteries, solid-state (SS) nuclear magnetic resonance (NMR) of lithium moves into focus of current research. Theoretical simulations of magnetic resonance parameters facilitate the analysis and interpretation of experimental Li SS-NMR spectra and provide unique insight into physical and chemical processes that are determining the spectral profile. In the present paper, the accuracy and reliability of the theoretical simulation methods of Li chemical shielding values is benchmarked by establishing a reference scale for Li SS-NMR of diamagnetic compounds. The impact of geometry, ionic mobility and relativity are discussed. Eventually, the simulation methods are applied to the more complex lithium titanate spinel (Li4Ti5O12, LTO), which is a widely discussed battery anode material. Simulation of the Li SS-NMR spectrum shows that the commonly adopted approach of assigning the resonances to individual crystallographic sites is not unambiguous.

Investigation of the Li-ion conduction behavior in the Li10GeP2S12 solid electrolyte by two-dimensional T1-spin alignment echo correlation NMR.

Li10GeP2S12 (LGPS) is the fastest known Li-ion conductor to date due to the formation of one-dimensional channels with a very high Li mobility. A knowledge-based optimization of such materials for use, for example, as solid electrolyte in all-solid-state batteries requires, however, a more comprehensive understanding of Li ion conduction that considers mobility in all three dimensions, mobility between crystallites and different phases, as well as their distributions within the material. The spin alignment echo (SAE) nuclear magnetic resonance (NMR) technique is suitable to directly probe slow Li ion hops with correlation times down to about 10-5 s, but distinction between hopping time constants and relaxation processes may be ambiguous. This contribution presents the correlation of the 7Li spin lattice relaxation (SLR) time constants (T1) with the SAE decay time constant τc to distinguish between hopping time constants and signal decay limited by relaxation in the τc distribution. A pulse sequence was employed with two independently varied mixing times. The obtained multidimensional time domain data was processed with an algorithm for discrete Laplace inversion that does not use a non-negativity constraint to deliver 2D SLR-SAE correlation maps. Using the full echo transient, it was also possible to estimate the NMR spectrum of the Li ions responsible for each point in the correlation map. The signal components were assigned to different environments in the LGPS structure.

Botryoid-type of embryonal rhabdomyosarcoma of renal pelvis in a young woman.

A 22-year-old woman presented with three weeks history of intermittent left loin pain, on radiological evaluation by U\S and MRI revealed left renal pelvic mass, ureterorenoscopy and biopsy taken, but couldn't reveal definitive diagnosis other than presence of a malignant process. Left nephroureterctomy was performed. Grossly there is a polypoid mass attached to the upper pole of the kidney by stalk. Light microscopic examination and immunohistochemical staining confirm a diagnosis of Botryoid-type of embryonal rhabdomyosarcoma. Treatment and follow up to 1 year is mentioned. Reviewing the literature the presented case is the second of this tumor in adult renal pelvis.

Multimodal reperfusion therapy for large hemispheric infarcts in octogenarians: is good outcome a realistic goal?

BACKGROUND AND PURPOSE: MMRT may be beneficial in a subset of patients with large hemispheric stroke who cannot be treated with systemic thrombolysis. Because most previous studies only included relatively young patients, the outcome of very old patients given MMRT remains unknown. MATERIALS AND METHODS: Consecutive patients with large hemispheric stroke treated with MMRT and admitted to intensive care were included. We compared neurologic and functional outcomes between patients younger and older than 80 years. RESULTS: We included 14 patients older than 80 years and compared them with 66 patients who were younger than 80. Cerebrovascular risk factor profile, admission NIHSS scores, stroke etiology and pathogenesis, and procedure-related variables did not differ between the groups except for a higher prevalence of smoking in younger patients. Excellent target vessel recanalization (Thrombolysis in Myocardial Infarction score of 3) and good outcome at 90 days (modified Rankin Score ≤ 2) were more common in younger patients (45% versus 14%, P = .047, and 41% versus 0%, P = .008, respectively). In contrast, mortality rates were higher in octogenarians (43% versus 17%, respectively). CONCLUSIONS: In this study, very old patients had higher chances of mortality and a very low probability of achieving functional independence even after MMRT. Further prospective studies are needed to examine the futility of MMRT in the very old.

Rehabilitation outcomes of stroke patients treated with multi-modal endovascular reperfusion therapy.

AIM: The aim of this study was to investigate the influence of multi-modal endovascular reperfusion therapy (MMRT) on functional outcomes following rehabilitation. METHODS: Data from 14 MMRT-treated patients were analyzed and compared to MMRT-ineligible, age and stroke severity-matched patients treated at the same Neurological and Rehabilitation departments. Neurological evaluation was assessed with the NIH stroke scale (NIHSS). Activity of daily living was measured using the FIMTM instrument. Functional outcome was measured using the modified Rankin scale (mRS). RESULTS: The baseline characteristics of both groups were similar. NIHSS scores were lower in the MMRT group and they had slightly better functional and rehabilitation scores on admission to rehabilitation. At the end of rehabilitation, more MMRT-treated patients reached functional independence (mRS≤2; 50% vs. 7% respectively P=0.03). FIM scores were also higher in the MMRT group (mean score 93.3 vs. 87.7, respectively) but the difference did not reach significance. The delta in FIM and NIHSS scores obtained during rehabilitation did not significantly differ between the groups. MMRT remained a significant modifier of good outcome after regression analysis (OR 21.5 95% CI 1.1-410). CONCLUSION: MMRT-treated patients have better chances of attaining independence after rehabilitation therapy. However, the additional improvements gained while in active rehabilitation were independent of reperfusion status.

Videourodynamic changes of botulinum toxin A in patients with neurogenic bladder dysfunction (NBD) and idiopathic detrusor overactivity (IDO) refractory to drug treatment.

PURPOSE: To document the videourodynamic changes and the efficacy and safety profile of botulinum toxin A (BoNT-A, Dysport(®)) in neurogenic bladder dysfunction (NBD) including neurogenic detrusor overactivity, low-compliance and break-low-compliance and idiopathic detrusor overactivity (IDO), in patients refractory to drug treatment. METHODS: Sixty-four patients with NBD and 170 patients with IDO were treated between 2002 and 2007. Diagnostic approach included medical history, bladder diary, standardised questionnaire rating quality of life, sonography, videourodynamic and temporary sacral nerve block. All patients received BoNT-A-injection under local anaesthesia. Patients with NBD received 500 mouse units (MU) and patients with IDO received 250 MU BoNT-A, injected into ten sites including the trigonum. Patients were followed up 6 weeks after injection. RESULTS: For NBD, 58/64 (91%) patients achieved satisfactory continence during the day as well as significant reduction in incontinence episodes and improvement in quality of life. For IDO, 158/170 (93%) were responders with regard to urgency and urge incontinence. Urodynamical changes included significant improvement in the following parameters in both groups: increase in maximum cystometric capacity and decrease in detrusor pressure. BoNT-A was well tolerated; no drug-related side effects were documented. No de novo vesicoureteral reflux was induced. Long-term follow-up revealed a mean duration effect of BoNT-A of 5.7 months in NBD and 4.9 months in IDO. CONCLUSIONS: BoNT-A is highly effective in NBD as well as in IDO suggesting that this is a good treatment option for patients with detrusor overactivity. Furthermore, intratrigonal injection is safe and not associated with vesicoureteral reflux.

Characterization of non-stoichiometric co-sputtered Ba0.6Sr0.4(Ti (1-x)Fe(x))(1+x)O(3-δ) thin films for tunable passive microwave applications.

The fabrication of novel iron-doped barium strontium titanate thin films by means of radio frequency (RF) magnetron co-sputtering is shown. Investigations of the elemental composition and the dopant distribution in the thin films obtained by X-ray photoelectron spectroscopy, Rutherford backscattering spectrometry, and time-of-flight secondary ion mass spectroscopy reveal a homogeneous dopant concentration throughout the thin film. The incorporation of the iron dopant and the temperature-dependent evolution of the crystal structure and morphology are analyzed by electron paramagnetic resonance spectroscopy, X-ray diffraction, Raman spectroscopy, atomic force microscopy, and scanning electron microscopy. In summary, these results emphasize the RF magnetron co-sputter process as a versatile way to fabricate doped thin films.

Prior use of statins and outcome in patients with intracerebral haemorrhage.

BACKGROUND: Pre-treatment with cholesterol lowering drugs of the statin family may exert protective effects in patients with ischaemic stroke and subarachnoid haemorrhage but their effects are not clear in patients with intracerebral haemorrhage (ICH). METHODS: We recruited patients admitted to our University Hospital with an acute ICH and analysed pre-admission demographic variables, pre-morbid therapy, clinical and radiological prognostic markers and outcome variables including 90-day modified Rankin score and NIH stroke scale score (NIHSS). RESULTS: We recruited 399 patients with ICH of which 101 (25%) were using statins. Statin users more often had vascular risk factors, had significantly lower haematoma volumes (P = 0.04) and had lower mortality rates compared with non-users (45.6% vs. 56.1%; P = 0.11). However, statin treatment did not have a statistically significant impact on mortality or functional outcome on multiple logistic regression analysis. CONCLUSIONS: Treatment with statins prior to ICH failed to show a significant impact on outcome in this analysis despite lower haematoma volumes.

Electron paramagnetic resonance structure investigation of copper complexation in a hemicarcerand.

The double-bridged hemicarcerand [A,B-(CH2OH)2-cavitand]-(CH2NHCH2)2-[A,B-(CH2OH)2-cavitand] 23 (and several other related compounds) was synthesized by the condensation of the two complementary precursors A,B-(CH2NH2)2(CH2OH)2-cavitand and A,B-(CH2Br)2(CH2OAc)2-cavitand followed by hydrolysis of the acetate groups. This hemicarcerand has nitrogen and oxygen donor atoms located on the interior of the spherical cavity and thus allows endohedral coordination of metal ions. The cavity has a volume of approximately 0.12 nm3, a value obtained by calculating a Connolly-type contact surface and the molecular electrostatic potential. The Cu2+ complex of hemicarcerand 23 was studied in detail by EPR and DFT calculations at the UB3LYP/6-31G level to verify the anticipated endohedral nature of the metal complex. It could be shown that the copper ion is coordinated to four oxygen donor atoms and no deviation from axial symmetry at the copper site could be detected. No direct coordination to nitrogen atoms of the hemicarcerand could be observed; however, complexation with DMF solvent molecules was detected by ESEEM and HYSCORE experiments. The closed structure of the hemicarcerand was also confirmed by an evaluation of proton-copper distances. Results from DFT calculations are in accord with the EPR results, and further support suggested coordination of the Cu(II) within the hemicarcerand cavity by four oxygen donor atoms.

A small paramagnetic platinum cluster in an NaY zeolite: characterization and hydrogen adsorption and desorption.

A well-defined cluster containing 12 equivalent platinum atoms was prepared by ion exchange of an NaY zeolite, followed by hydrogen reduction. It was characterized by electron paramagnetic resonance (EPR) spectroscopy, hyperfine sublevel correlation (HYSCORE), and theoretical calculations. Combing the results of the experiments with density functional calculations, the likely structure of this cluster is icosahedral Pt13Hm, possibly with a low positive charge. The adsorbed H/D on the Pt cluster surface can be exchanged reversibly at room temperature. From H/D desorption experiments, an H2 binding energy of 1.36 eV is derived, in reasonable agreement with the calculated value but clearly larger than that for a (111) Pt single-crystal surface, revealing a finite size effect. While the hydrogen-covered cluster should clearly be regarded as a molecule, it is conceivable that the cluster adopts metallic character upon hydrogen desorption. It is likely that up to m=30 H atoms bind to this cluster with 12 surface atoms, which has important implications for the determination of the dispersion of small Pt catalyst particles by hydrogen chemisorption. Calculations as well as experiments give evidence of an interesting magnetic behavior with high-spin states playing a prominent role. There are strong indications that a reservoir of EPR silent but structurally similar clusters exists which can partly be converted to EPR visible species by H/D exchange or by gas adsorption.

Electron paramagnetic resonance investigation of endohedral fullerenes N@C(60) and N@C(70) in a liquid crystal.

Endohedral fullerenes N@C(60) and N@C(70) were dissolved in the liquid crystal 4-methoxybenzylidene-4'-n-butylaniline (MBBA) and investigated by electron paramagnetic resonance. In both cases well resolved EPR spectra give proof for molecular orientation in the nematic mesophase. Spectral features are dominated by a nonvanishing zero-field interaction, indicating a deviation from spherical spin density distribution at the encased nitrogen atom. In N@C(70), a maximum order parameter O(33) = 0.18(3), correlated with the long axis of the cage, and a zero-field-splitting parameter D = -2.6(4) MHz were determined. A persistent zero-field splitting is also observed in C(60) via the quartet spin of the encapsulated nitrogen, although no assignment of the director with respect to the molecular frame is possible. The observed line splitting is indicative of pseudo orientation of the rapidly rotating cage in this case.

[Zonographic study of pleural lesions due to asbestos dust]. / Zonograficheskie issledovaniia porazhenii plevry, vyzvannykh asbestnoi pyl'iu.

Results of zonographic examination of the chest were compared with roentgenographic data in 34 patients with asbestos hyalinosis of different severity. The zonographic substrate of pleural hyalinosis are echo-poor intermediate spaces that are visualized bilaterally in different parts of the pleura. It was established that zonographic examination is more sensitive than roentgenography for revealing pleura hardening. Chest zonography is recommended to reveal of exclude pleura hyalinosis induced by asbestos in the absence of typical asbestos-induced changes on the pulmonary x-ray picture.