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Ti40Zr10Cu32Pd14Ga4 and Ti40Zr10Cu32Pd14Sn4 (in at%) bulk metallic glasses (BMGs) with different geometries (wedges, rods, ribbons and discs) were prepared by suction casting, melt spinning and splat quenching, respectively. For comparison, the reference Ti40Zr10Cu36Pd14 BMG was cast as a rod with 2 mm diameter and in wedge-shaped form. High-energy X-ray diffraction measurements yielded a critical casting thickness of 2.4, 2.1 and at least 4 mm for the reference, Ga-containing, and Sn-containing BMGs, respectively. The extension of the supercooled liquid region of about 50 K, measured for the glassy rods and ribbons by differential scanning calorimetry, is larger than that of only 20 K found for the splat-quenched discs. As to the alloys’ mechanical properties, the Ti40Zr10Cu36Pd14 glassy rods deform plastically in compression up to a strain of 3.8% and possess a Young’s modulus of 78 GPa. The Sn- and Ga- containing BMG rods reach respectively a plastic strain of 6.1% and 4.7%, and a Young’s modulus of 72 and 63 GPa. Corrosion tests were performed by electrochemical experiments, and the highest pitting resistance was observed for Ti40Zr10Cu32Pd14Sn4 (pitting overpotential ηpit = 446 mV) compared to Ti40Zr10Cu32Pd14Ga4 (379 mV) and Ti40Zr10Cu36Pd14 (183 mV). The results of live/dead assay and cell viability revealed excellent biocompatibility for the Ga-containing BMGs. ISSN:0925-8388 ISSN:1873-4669

Background: Oxidative stress and glutathione (GSH) metabolism dysregulation has been implicated in the pathophysiology of schizophrenia. GAG-trinucleotide repeat (TNR) polymorphisms in the glutamate-cysteine ligase catalytic gene (GCLC), the rate-limiting enzyme for GSH synthesis, are associated with schizophrenia. In addition, GSH may serve as a reserve pool for neuronal glutamate (Glu) through the γ-glutamyl cycle. The aim of this study is to investigate brain [GSH] and its association with GCLC polymorphism, peripheral redox indices and brain Glu. Methods: Magnetic resonance spectroscopy was used to measure [GSH] and [Glu] in the medial prefrontal cortex (mPFC) of 25 early-psychosis patients and 33 controls. GCLC polymorphism was genotyped, glutathione peroxidases (GPx) and glutathione reductase (GR) activities were determined in blood cells. Results: Significantly lower [GSH mPFC ] in GCLC high-risk genotype subjects were revealed as compared to low-risk genotype subjects independent of disease status. In male subjects, [GSH mPFC ] and blood GPx activities correlate positively in controls ( P = .021), but negatively in patients ( P = .039). In GCLC low-risk genotypes, [Glu mPFC ] are lower in patients, while it is not the case for high-risk genotypes. Conclusions: GCLC high-risk genotypes are associated with low [GSH mPFC ], highlighting that GCLC polymorphisms should be considered in pathology studies of cerebral GSH. Low brain GSH levels are related to low peripheral oxidation status in controls but with high oxidation status in patients, pointing to a dysregulated GSH homeostasis in early psychosis patients. GCLC polymorphisms and disease associated correlations between brain GSH and Glu levels may allow patients stratification.

Osteoradionecrosis (ORN) is a serious complication after radiotherapy for head and neck cancer and is a challenging condition for both the therapist and the patient because of its difficult treatment. Different non-invasive approaches have been published for the treatment of low-grade ORN cases without establishing a standard regimen for treatment. Based on the approach of ORN pathogenesis, the so-called radiatio-induced fibroathrophic process (RIF), a new treatment concept with pentoxifylline and tocopherol (PENTO) has been published. The results of PENTO therapy seem promising as a conservative treatment approach for mild ORN or as an alternative when surgical intervention is not possible or desired. The present study summarizes the current state of the literature and shows the effectiveness of PENTO therapy based on a case report.

The aim of this study was to determine the influence of perioperative fluid management and administration of vasopressors on early surgical revision and flap-related complications in free tissue transfer.Intraoperative amount of fluid and of vasopressors, relevant perioperative parameters, and comorbidities were recorded in 131 patients undergoing head and neck microvascular reconstruction and compared with early surgical complications, defined as interventions requiring surgery after a flap-related complication, and/or other surgical problems in the operating room within 30 days after initial surgery. The relationship between perioperative variables for each revision category was determined using an optimized multiple logistic regression.The administration of diuretics (p=0.001) as a treatment for perioperative fluid overload and the type of flap (p=0.019) was associated with a higher risk of early surgical revisions. Perioperative fluid overload (p=0.039) is significantly related to flap-related complications. We found no effect of intraoperative administration of vasopressors on early surgical revisions (p=0.8) or on flap-related complications (norepinephrine p=0.6, dobutamine p=0.5).Perioperative fluid overload is associated with higher risks of early surgical revision and flap-related complications. In contrast, the administration of vasopressors seemed to have no effect on either surgical revision rate or flap-related complications.In patients receiving microvascular reconstructions, a balanced fluid administration perioperatively and a targeted use of vasopressors should be the necessary strategy to reduce the complication rates in head and neck surgery.

Purpose At 7 Tesla (T), conventional static field (B0) projection mapping techniques, e.g., FASTMAP, FASTESTMAP, lead to elevated specific absorption rates (SAR), requiring longer total acquisition times (TA). In this work, the series of adiabatic pulses needed for slab selection in FASTMAP is replaced by a single two-dimensional radiofrequency (2D-RF) pulse to minimize TA while ensuring equal shimming performance. Methods Spiral gradients and 2D-RF pulses were designed to excite thin slabs in the small tip angle regime. The corresponding selection profile was characterized in phantoms and in vivo. After optimization of the shimming protocol, the spectral linewidths obtained after 2D localized shimming were compared with conventional techniques and published values from (Emir et al NMR Biomed 2012;25:152–160) in six different brain regions. Results Results on healthy volunteers show no significant difference (P > 0.5) between the spectroscopic linewidths obtained with the adiabatic (TA = 4 min) and the new low-SAR and time-efficient FASTMAP sequence (TA = 42 s). The SAR can be reduced by three orders of magnitude and TA accelerated six times without impact on the shimming performances or quality of the resulting spectra. Conclusion Multidimensional pulses can be used to minimize the RF energy and time spent for automated shimming using projection mapping at high field.

Purpose The macromolecule signal plays a key role in the precision and the accuracy of the metabolite quantification in short-TE 1H MR spectroscopy. Macromolecules have been reported at 1.5 Tesla (T) to depend on the cerebral studied region and to be age specific. As metabolite concentrations vary locally, information about the profile of the macromolecule signal in different tissues may be of crucial importance. Methods The aim of this study was to investigate, at 7T for healthy subjects, the neurochemical profile differences provided by macromolecule signal measured in two different tissues in the occipital lobe, predominantly composed of white matter tissue or of grey matter tissue. Results White matter-rich macromolecule signal was relatively lower than the gray matter-rich macromolecule signal from 1.5 to 1.8 ppm and from 2.3 to 2.5 ppm with mean difference over these regions of 7% and 12% (relative to the reference peak at 0.9 ppm), respectively. The neurochemical profiles, when using either of the two macromolecule signals, were similar for 11 reliably quantified metabolites (CRLB < 20%) with relatively small concentration differences (< 0.3 μmol/g), except Glu (± 0.8 μmol/g). Conclusion Given the small quantification differences, we conclude that a general macromolecule baseline provides a sufficiently accurate neurochemical profile in occipital lobe at 7T in healthy human brain.

The broad resonances underlying the entire (1) H NMR spectrum of the brain, ascribed to macromolecules, can influence metabolite quantification. At the intermediate field strength of 3 T, distinct approaches for the determination of the macromolecule signal, previously used at either 1.5 or 7 T and higher, may become equivalent. The aim of this study was to evaluate, at 3 T for healthy subjects using LCModel, the impact on the metabolite quantification of two different macromolecule approaches: (i) experimentally measured macromolecules; and (ii) mathematically estimated macromolecules. Although small, but significant, differences in metabolite quantification (up to 23% for glutamate) were noted for some metabolites, 10 metabolites were quantified reproducibly with both approaches with a Cramer-Rao lower bound below 20%, and the neurochemical profiles were therefore similar. We conclude that the mathematical approximation can provide sufficiently accurate and reproducible estimation of the macromolecule contribution to the (1) H spectrum at 3 T. Copyright © 2013 John Wiley & Sons, Ltd.

After the landmark studies reporting changes in the cerebral metabolic rate of glucose (CMR(Glc) ) in excess of those in oxygen (CMR(O2) ) during physiological stimulation, several studies have examined the fate of the extra carbon taken up by the brain, reporting a wide range of changes in brain lactate from 20% to 250%. The present study reports functional magnetic resonance spectroscopy measurements at 7 Tesla using the enhanced sensitivity to study a small cohort (n = 6). Small increases in lactate (19% ± 4%, P < 0.05) and glutamate (4% ± 1%, P < 0.001) were seen within the first 2 min of activation. With the exception of glucose (12% ± 5%, P < 0.001), no other metabolite concentration changes beyond experimental error were significantly observed. Therefore, the present study confirms that lactate and glutamate changes during physiological stimulation are small (i.e. below 20%) and shows that the increased sensitivity allows reproduction of previous results with fewer subjects. In addition, the initial rate of glutamate and lactate concentration increases implies an increase in CMR(O2) that is slightly below that of CMR(Glc) during the first 1-2 min of activation. © 2013 Wiley Periodicals, Inc.

Proton T1 relaxation times of metabolites in the human brain have not previously been published at 7 T. In this study, T1 values of CH3 and CH2 group of N-acetylaspartate and total creatine as well as nine other brain metabolites were measured in occipital white matter and gray matter at 7 T using an inversion-recovery technique combined with a newly implemented semi-adiabatic spin-echo full-intensity acquired localized spectroscopy sequence (echo time = 12 ms). The mean T1 values of metabolites in occipital white matter and gray matter ranged from 0.9 to 2.2 s. Among them, the T1 of glutathione, scyllo-inositol, taurine, phosphorylethanolamine, and N-acetylaspartylglutamate were determined for the first time in the human brain. Significant differences in T1 between white matter and gray matter were found for water (-28%), total choline (-14%), N-acetylaspartylglutamate (-29%), N-acetylaspartate (+4%), and glutamate (+8%). An increasing trend in T1 was observed when compared with previously reported values of N-acetylaspartate (CH3 ), total creatine (CH3 ), and total choline at 3 T. However, for N-acetylaspartate (CH3 ), total creatine, and total choline, no substantial differences compared to previously reported values at 9.4 T were discernible. The T1 values reported here will be useful for the quantification of metabolites and signal-to-noise optimization in human brain at 7 T.

This paper presents the multiple set of requirements for the ITER magnetic diagnostic systems and the current status of the various R&D activities performed by the EU partners.

Background P-MRS provides direct insights into myocardial energy supply (ATP, ADP, phosphocreatine (PCr) and inorganic phosphate). An initial study demonstrated that 7T cardiac P-MRS has 2.8x greater SNR than at 3T. However, the translation of more sophisticated P-MRS protocols to 7T is particularly challenged by increased RF heating of tissue at 7T. Chen and Ackerman introduced the surface spoiling coil in 1990: a concept that was recently further developed (Boer MRM 2014) for lipid suppression in human brain H-CSI. In this work, we introduce the first crusher coil for cardiac P-MRS at 7T. This allows us to saturate more efficiently skeletal muscle signal removing the RF heating associated with RF saturation bands.

Recent studies at high field (7 Tesla) have reported small metabolite changes, in particular lactate and glutamate (below 0.3 μmol/g) during visual stimulation. These studies have been limited to the visual cortex because of its high energy metabolism and good magnetic resonance spectroscopy (MRS) sensitivity using surface coil. The aim of this study was to extend functional MRS (fMRS) to investigate for the first time the metabolite changes during motor activation at 7 T. Small but sustained increases in lactate (0.17 μmol/g ± 0.05 μmol/g, p < 0.001) and glutamate (0.17 μmol/g ± 0.09 μmol/g, p < 0.005) were detected during motor activation followed by a return to the baseline after the end of activation. The present study demonstrates that increases in lactate and glutamate during motor stimulation are small, but similar to those observed during visual stimulation. From the observed glutamate and lactate increase, we inferred that these metabolite changes may be a general manifestation of the increased neuronal activity. In addition, we propose that the measured metabolite concentration increases imply an increase in ΔCMRO2 that is transiently below that of ΔCMRGlc during the first 1 to 2 minutes of the stimulation.

Oral health (OH) is indivisible from general health. Several studies have established the link between morbi-mortality, especially cardiovascular, and bad OH, particularly in the case of edentation. Regrettably, part of the population choses dental care renunciation for financial reasons. The primary care physician (PCP), as the health professionnal with the most frequent and intense contacts with the patients, plays an important role to reinforce prevention measures, OH maintenance and to detect oral pathologies. To fulfill this mission, he has to be trained to endo-buccal examination. Furthermore, both the PCP and the dentist have to proactively build an interprofessional approach to promote patients' OH.

This paper reports the mechanical and electrical tests performed for the prototyping of the ITER high-frequency magnetic sensor and the analysis of the measurement performance of this diagnostic. The current design for the sensor is not suitable for manufacturing for ITER due to the high likelihood of breakages of the un-guided tungsten wire during the winding. A number of alternative designs and manufacturing processes have been investigated, with the Low Temperature Co-fired Ceramic technology giving the best results. The measurement performance of the baseline system design for the high-frequency magnetic diagnostic cannot meet the intended ITER requirements due to its intrinsic spatial periodicities.

PURPOSE The macromolecule signal plays a key role in the precision and the accuracy of the metabolite quantification in short TE (1) H MR spectroscopy. Macromolecules have been reported at 1.5 Tesla (T) to depend on the cerebral studied region and to be age specific. As metabolite concentrations vary locally information about the profile of the macromolecule signal in different tissues may be of crucial importance. METHODS The aim of this study was to investigate at 7T for healthy subjects the neurochemical profile differences provided by macromolecule signal measured in two different tissues in the occipital lobe predominantly composed of white matter tissue or of grey matter tissue. RESULTS White matter rich macromolecule signal was relatively lower than the gray matter rich macromolecule signal from 1.5 to 1.8 ppm and from 2.3 to 2.5 ppm with mean difference over these regions of 7 and 12 (relative to the reference peak at 0.9 ppm) respectively. The neurochemical profiles when using either of the two macromolecule signals were similar for 11 reliably quantified metabolites (CRLB?20) with relatively small concentration differences (< 0.3 µmol/g) except Glu (± 0.8 µmol/g). CONCLUSION Given the small quantification differences we conclude that a general macromolecule baseline provides a sufficiently accurate neurochemical profile in occipital lobe at 7T in healthy human brain. Magn Reson Med 2013. © 2013 Wiley Periodicals Inc.

The ITER high-frequency (HF) magnetic diagnostic system has to provide essential measurements of MHD instabilities with vertical bar delta B-MEAS/B-POL vertical bar similar to 10(-4) (similar to 1 G) for frequencies up to 2 MHz to resolve toroidal mode numbers (n) in the range vertical bar n vertical bar = 10 to vertical bar n vertical bar = 50. A review of the measurement requirements for HF MHD instabilities in ITER was initiated during the TW4 work-program and led to significant interest for physics and real-time control issues in measuring modes with vertical bar delta(MEAS)vertical bar as low as similar to 10(-3) G at the position of the sensors, with vertical bar n vertical bar

The ITER high-frequency (HF) magnetic sensor is currently intended to be a conventional, Mirnov-type, pickup coil, designed to provide measurements of magnetic instabilities with magnitude as low as |dB|~10e-4G at the position of the sensors and up to frequencies of at least 300 kHz. Previous prototyping of this sensor has indicated that a number of problems exist with this conventional design that are essentially related to the winding^process and the differential thermal expansion between the metallic wire and the ceramic spacers. Hence, a non-conventional HF magnetic sensor has been designed and prototyped in-house in different variants using low-temperature co-fired ceramic (LTCC) technology, which involves a series of stacked ceramic substrates with a circuit board printed on them with a metallic ink (silver in our case). A method has then been developed to characterize the electrical properties of these sensors from the direct-current range up to frequencies in excess of 10MHz. This method has been successfully benchmarked against the measurements for the built sensors and allows the electrical properties of LTCC prototypes to be predicted with confidence and without the need of actually building them, which therefore significantly simplifies future research and development (R&D) activities. When appropriate design choices are made, LTCC sensors are found to meet in full the volume occupation constraints and the requirements for the sensor's electrical properties that are set out for the ITER HF magnetic diagnostic system. This non-conventional technology is therefore recommended for further R&D and prototyping work, particularly for a three-dimensional sensor, and possibly using materials more suitable for use in the ITER environment, such as palladium and platinum inks, which could remove the perceived risk of transmutation under the heavy neutron flux that we may have with the Au (to Hg, then to Pb) or the Ag (to Cd) metallic inks currently used in LTCC devices.