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The current work involves the use of flash auto combustion procedure to synthesize nano-ferrites Mn0.6Zn0.4LaxFe2-xO4, (x = 0.00, 0.02, 0.04, 0.06, 0.08, and 0.10) annealing at 500 °C for 4 h. X-ray Diffraction (XRD), Fourier transition infrared spectroscopy (FTIR), and high-resolution transmission electron microscopy (HRTEM) were used to characterize the structural properties of produced samples. Scanning electron microscopy (SEM) was utilized to examine the surface morphology of the samples at various Lanthanum concentrations. From XRD, the spinel cubic structure for all samples with few traces of secondary phase at high La concentrations is assured. The crystallite size is estimated to be in the nanoscale range of 13.16–18.13 nm using the Debye–Scherrer formula. The appearance of characteristic vibrational bands near 460 cm−1 and 563 cm−1, which correspond to the octahedral and tetrahedral sites, respectively, confirms the formation of the spinel structure. SEM micrographs show that the grains are nearly irregular in shape, and the accumulation of La+3 ions at the grain boundaries exerts tensile strength and pressure on the grain itself, reducing the grain size. The particle size estimated by TEM coincides well with the crystallite size determined by XRD. The thermogravimetric analysis, (TGA), was used to investigate the thermal properties of the nanoferrites from room temperature to 1000 °C. In comparison to the other samples, the sample with x = 0.04 has greater thermal stability and the TEM measurement indicates that this sample has the smallest particle size. Therefore, we can assert that the thermal stability improves as the particle size decreases. The magnetic permeability was measured in the temperature range 303–773 K at a fixed frequency of 10 kHz and at various La contents. The sample with x = 0.04 has a minimal permeability value, showing that the separation brought on by La ions has diminished the super exchange contact between magnetic ions. [ABSTRACT FROM AUTHOR]

The integration of graphene (Gr) with nitride semiconductors is highly interesting for applications in high-power/high-frequency electronics and optoelectronics. In this work, we demonstrated the direct growth of Gr on Al0.5Ga0.5N/sapphire templates by propane (C3H8) chemical vapor deposition at a temperature of 1350 °C. After optimization of the C3H8 flow rate, a uniform and conformal Gr coverage was achieved, which proved beneficial to prevent degradation of AlGaN morphology. X-ray photoemission spectroscopy revealed Ga loss and partial oxidation of Al in the near-surface AlGaN region. Such chemical modification of a ∼2 nm thick AlGaN surface region was confirmed by cross-sectional scanning transmission electron microscopy combined with electron energy loss spectroscopy, which also showed the presence of a bilayer of Gr with partial sp2/sp3 hybridization. Raman spectra indicated that the deposited Gr is nanocrystalline (with domain size ∼7 nm) and compressively strained. A Gr sheet resistance of ∼15.8 kΩ sq−1 was evaluated by four-point-probe measurements, consistently with the nanocrystalline nature of these films. Furthermore, nanoscale resolution current mapping by conductive atomic force microscopy indicated local variations of the Gr carrier density at a mesoscopic scale, which can be ascribed to changes in the charge transfer from the substrate due to local oxidation of AlGaN or to the presence of Gr wrinkles. [ABSTRACT FROM AUTHOR]

Graphene and AlN are promising materials, interesting to combine together. In this study, we will present first results for direct growth of graphene on bulk AlN and on AlN templates using chemical vapor deposition, including the annealing of these substrates at high temperatures. Atomic force microscopy (AFM) enabled us to study the evolution of the AlN surface morphology after annealing and growth. Few-layer graphene deposition is demonstrated on the basis of X-ray photoemission and Raman spectroscopy. AFM view of graphene wrinkles on the N-face of bulk AlN. [ABSTRACT FROM AUTHOR]

Group III nitride semiconductors (III-N), including GaN, AlN, InN, and their alloys, are currently the materials of choice for many applications in optoelectronics (light-emitting diodes, laser diodes), and high-power and high-frequency transistors. Due to its attractive electrical, optical, mechanical, and thermal properties, graphene (Gr) integration with III-N technology has been considered in the last few years, in order to address some of the major issues which still limit the performances of GaN-based devices. To date, most of the studies have been focused on the use of Gr as transparent conductive electrode (TCE) to improve current spreading from top electrodes and light extraction in GaN-LEDs. This paper will review recent works evaluating the benefits of Gr integration with III-N for high power and high frequency electronics. From the materials side, recent progresses in the growth of high quality GaN layers on Gr templates and in the deposition of Gr on III-N substrates and templates will be presented. From the applications side, strategies to use Gr for thermal management in high-power AlGaN/GaN transistors will be discussed. Finally, recent proposals of implementing new ultra-high-frequency (THz) transistors, such as the Gr base hot electron transistor (GBHET), by Gr integration with III-N will be highlighted. [ABSTRACT FROM AUTHOR]

Management of anthracycline extravasation is problematic and most reports are anecdotal. On September 6, 2007, the U.S. Food and Drug Administration approved Totecttrade mark 500 mg (dexrazoxane hydrochloride for injection) for the treatment of extravasation resulting from i.v. anthracycline chemotherapy. In two studies, a total of 57 evaluable patients experienced extravasation from peripheral vein or central venous access sites with local swelling, pain, or redness. The presence of anthracycline in skin biopsy tissue was confirmed by tissue fluorescence, and treatment with a 3-day schedule of dexrazoxane began within 6 hours of the event. The primary endpoint was a reduction in the need for surgical intervention. Only one patient required surgical repair of the injury site, and late sequelae in the remainder were absent or mild. Also, the sponsor, TopoTarget A/S, Copenhagen, Denmark, performed controlled nonclinical studies in support of dexrazoxane dose and timing for the reduction of tissue injury resulting from anthracycline extravasation. For this uncommon but serious complication of anthracycline therapy, the need for surgical intervention was 1.7% with this regimen. [ABSTRACT FROM AUTHOR]

PURPOSE: On May 17, 2007, doxorubicin HCl liposome injection (Doxil) in combination with bortezomib (Velcade) received approval from the US Food and Drug Administration (FDA) for the treatment of relapsed or refractory multiple myeloma after at least one prior therapy that has not included bortezomib. Liposomal doxorubicin's efficacy and safety were demonstrated in a phase III, randomized, multicenter, international trial comparing the combination of this agent plus bortezomib vs bortezomib alone in multiple myeloma patients who had not previously received bortezomib and had received at least one prior therapy. Here we summarize the FDA review of the data that support this approval. EXPERIMENTAL DESIGN AND RESULTS: An interim analysis of time to disease progression (TTP), the primary endpoint, was conducted after 249 TTP events in this study that randomized 324 patients to liposomal doxorubicin plus bortezomib treatment and 322 patients to bortezomib monotherapy. Time to progression was significantly prolonged in the combination arm (median TTP = 9.3 months) compared with bortezomib monotherapy (median TTP = 6.5 months), P < .0001 (log-rank test); hazard ratio = 0.55 (95% confidence interval = 0.43-0.71). The response rates were similar between the two arms and not statistically different; however, among responding patients, the median duration of response was longer with the combination--10.2 months compared to 7.0 months in the monotherapy arm. Adverse reactions occurred more frequently with the combination therapy. As compared to the monotherapy, frequent grade 3/4 adverse reactions with the combination were neutropenia and thrombocytopenia. CONCLUSIONS: Liposomal doxorubicin received FDA approval for use in combination with bortezomib in patients with multiple myeloma who have not previously received bortezomib and have received at least one prior therapy. [ABSTRACT FROM AUTHOR]

PURPOSE: Topotecan, a camptothecin analog previously approved for the treatment of ovarian cancer and small-cell lung cancer, was granted regular approval by the US Food and Drug Administration (FDA) on June 14, 2006, for use in combination with cisplatin to treat women with stage IVB, recurrent, or persistent carcinoma of the cervix not amenable to curative treatment with surgery and/or radiation therapy. The purpose of this summary is to review the database supporting this approval. EXPERIMENTAL DESIGN: In a randomized multicenter study enrolling 293 eligible patients, topotecan plus cisplatin (TC) was compared with cisplatin monotherapy. The TC regimen consisted of cisplatin 50 mg/m2 IV over 1 hour on day 1 and topotecan 0.75 mg/m2 IV over 30 minutes on days 1, 2, and 3 every 21 days. RESULTS: There was a clinically relevant and statistically significant improvement in overall survival in the TC treatment arm. Median overall survival was 9.4 months (95% confidence interval [CI]:7.9-11.9) in the TC arm, compared to 6.5 months (95% CI:5.8-8.8) with cisplatin alone. The unadjusted hazard ratio for overall survival between treatment arms was 0.76 (95% CI: 0.59-0.98, P = .033) favoring the combination arm. The most common toxicities with TC included myelosuppression, nausea and vomiting, mucositis, rash, and hepatotoxicity. CONCLUSIONS: This report describes the FDA's review supporting this first approval of a chemotherapeutic drug for advanced cervical cancer based on demonstration of a survival benefit. [ABSTRACT FROM AUTHOR]

The article focuses on a study in which the effect of administering anti-lymphocyte serum (ALS) to the F1 hybrid recipient at various time intervals before and after the injection of parental donor cells has been investigated. The graft-verus-host (GVH) syndrome, as induced in F1 hybrid recipients by the injection of parental strain lymphoid cells, provides a simple system for studying how the activity of the small lymphocyte may be influenced by ALS. Previous studies have demonstrated that ALS treatment of the parental donor can render spleen, lymph node and thoracic duct cell suspensions unable to induce a GVH syndrome in F1 hybrid recipients.

The family of III-Nitride semiconductors has been under intensive research for almost 30 years and has revolutionized lighting applications at the dawn of the 21st century. However, besides the developments and applications achieved, nitride alloys continue to fuel the quest for novel materials and applications. We report on the synthesis of a new nitride-based compound by using annealing of AlN heteroepitaxial layers under a Si-atmosphere at temperatures between 1350 °C and 1550 °C. The structure and stoichiometry of this compound are investigated by high resolution transmission electron microscopy (TEM) techniques and energy dispersive X-Ray (EDX) spectroscopy. Results are supported by density functional theory (DFT) calculations. The identified structure is a derivative of the parent wurtzite AlN crystal where the anion sublattice is fully occupied by N atoms and the cation sublattice is the stacking of 2 different planes along <0001>: The first one exhibits a ×3 periodicity along <11–20> with 1/3 of the sites being vacant. The rest of the sites in the cation sublattice are occupied by an equal number of Si and Al atoms. Assuming a semiconducting alloy, a range of stoichiometries is proposed, Al5+αSi5+δN12 with α being between −2/3 and 1/4 and δ between 0 and 3/4. [ABSTRACT FROM AUTHOR]

The current work involves the use of flash auto combustion procedure to synthesize nano-ferrites Mn0.6Zn0.4LaxFe2-xO4, (x = 0.00, 0.02, 0.04, 0.06, 0.08, and 0.10) annealing at 500 °C for 4 h. X-ray Diffraction (XRD), Fourier transition infrared spectroscopy (FTIR), and high-resolution transmission electron microscopy (HRTEM) were used to characterize the structural properties of produced samples. Scanning electron microscopy (SEM) was utilized to examine the surface morphology of the samples at various Lanthanum concentrations. From XRD, the spinel cubic structure for all samples with few traces of secondary phase at high La concentrations is assured. The crystallite size is estimated to be in the nanoscale range of 13.16–18.13 nm using the Debye–Scherrer formula. The appearance of characteristic vibrational bands near 460 cm−1 and 563 cm−1, which correspond to the octahedral and tetrahedral sites, respectively, confirms the formation of the spinel structure. SEM micrographs show that the grains are nearly irregular in shape, and the accumulation of La+3 ions at the grain boundaries exerts tensile strength and pressure on the grain itself, reducing the grain size. The particle size estimated by TEM coincides well with the crystallite size determined by XRD. The thermogravimetric analysis, (TGA), was used to investigate the thermal properties of the nanoferrites from room temperature to 1000 °C. In comparison to the other samples, the sample with x = 0.04 has greater thermal stability and the TEM measurement indicates that this sample has the smallest particle size. Therefore, we can assert that the thermal stability improves as the particle size decreases. The magnetic permeability was measured in the temperature range 303–773 K at a fixed frequency of 10 kHz and at various La contents. The sample with x = 0.04 has a minimal permeability value, showing that the separation brought on by La ions has diminished the super exchange contact between magnetic ions. [ABSTRACT FROM AUTHOR]

The article discusses a study on population-based analyses of cancer incidence indicating that the relative incidence of adenocarcinoma is increasing.