Search

Ferromagnetic insulators are required for many new magnetic devices, such as dissipationless quantum-spintronic devices, magnetic tunneling junctions, etc. Ferromagnetic insulators with a high Curie temperature and a high-symmetry structure are critical integration with common single-crystalline oxide films or substrates. So far, the commonly used ferromagnetic insulators mostly possess low-symmetry structures associated with a poor growth quality and widespread properties. The few known high-symmetry materials either have extremely low Curie temperatures (≤16 K), or require chemical doping of an otherwise antiferromagnetic matrix. Here we present compelling evidence that the LaCoO3 single-crystalline thin film under tensile strain is a rare undoped perovskite ferromagnetic insulator with a remarkably high TC of up to 90 K. Both experiments and first-principles calculations demonstrate tensile-strain-induced ferromagnetism which does not exist in bulk LaCoO3 The ferromagnetism is strongest within a nearly stoichiometric structure, disappearing when the Co2+ defect concentration reaches about 10%. Significant impact of the research includes demonstration of a strain-induced high-temperature ferromagnetic insulator, successful elevation of the transition over the liquid-nitrogen temperature, and high potential for integration into large-area device fabrication processes.

BackgroundApproximately 70% of all patients with myelodysplastic syndrome (MDS) present with lower-risk disease. Some of these patients will initially respond to treatment with growth factors to improve anemia but will eventually cease to respond, while others will be resistant to growth factor therapy. Eventually, all lower-risk MDS patients require multiple transfusions and long-term therapy. While some patients may respond briefly to hypomethylating agents or lenalidomide, the majority will not, and new therapeutic options are needed for these lower-risk patients. Our previous clinical trials with ezatiostat (ezatiostat hydrochloride, Telentra®, TLK199), a glutathione S-transferase P1-1 inhibitor in clinical development for the treatment of low- to intermediate-risk MDS, have shown significant clinical activity, including multilineage responses as well as durable red-blood-cell transfusion independence. It would be of significant clinical benefit to be able to identify patients most likely to respond to ezatiostat before therapy is initiated. We have previously shown that by using gene expression profiling and grouping by response, it is possible to construct a predictive score that indicates the likelihood that patients without deletion 5q will respond to lenalidomide. The success of that study was based in part on the fact that the profile for response was linked to the biology of the disease.MethodsRNA was available on 30 patients enrolled in the trial and analyzed for gene expression on the Illumina HT12v4 whole genome array according to the manufacturer's protocol. Gene marker analysis was performed. The selection of genes associated with the responders (R) vs. non-responders (NR) phenotype was obtained using a normalized and rescaled mutual information score (NMI).ConclusionsWe have shown that an ezatiostat response profile contains two miRNAs that regulate expression of genes known to be implicated in MDS disease pathology. Remarkably, pathway analysis of the response profile revealed that the genes comprising the jun-N-terminal kinase/c-Jun molecular pathway, which is known to be activated by ezatiostat, are under-expressed in patients who respond and over-expressed in patients who were non-responders to the drug, suggesting that both the biology of the disease and the molecular mechanism of action of the drug are positively correlated.

High quality professional development programs and opportunities for teachers are a vital aspect in improving early student achievement. This study adopts a professional development model which tested the difference in early literacy skills and performance of students (n=2028) in Grades 1-3 over a 12-week teacher training program (n=25). The data were analyzed using ANOVA and indicated an overall significant improvement in all tested skills except for phonological awareness, such as rhyming word tasks and reading nonsense words, where there was a significant decrease in performance. The results also indicated a significant difference between gendered scores, where girls outperformed boys in all tested areas except vocabulary knowledge, where there was no statistical difference for Grade 1 and Grade 3 students. Informed by the data, this paper recommends greater teacher preparation in the areas of reading aloud, shared reading, phonics, and basic questioning techniques. [ABSTRACT FROM AUTHOR]

This issue is a collection of scholarship on school as community--a subject with prolific writings, but a sparse research base. Not another educational fad, community should be disentangled from the instrumental values (improving measurable student outcomes) that pervade education policy. In-depth field studies are needed. (MLH)

A study investigated the use of self-modeling to facilitate generalization and maintenance of the reduction of self-stimulation in a six-year-old boy with intellectual disability. The study used a videotape self-as-a-model method to successfully decrease hand flapping. (CR)

INTRODUCTION Conner Prairie is an interactive history park or a 'living museum.' Located 6 km north of Indianapolis in Fishers, Indiana, the 850 acres that presently comprise Conner Prairie have [...]

Magneto-transport measurements have been made on strain-free In0.25Ga0.75Sb/InAs superlattices grown on GaSb substrates. The superior structural quality of these superlattices compared to older materials in the literature resulted in a much higher resolution of the Shubnikov-de Haas oscillations. Three separate conduction channels were observed. Measurements with the magnetic field in the plane of the sample indicated that the channel with the longer period was due to three dimensional-like conduction within the superlattice while the other two channels showed two dimensional behavior most likely associated with conduction at the surface or interfaces between the superlattice and bulk-like layers. Comparison with multi-carrier analysis indicated that the channel with intermediate period was due to hole conduction while the others were due to electron conduction. Oscillations were observed at temperatures up to 20?K. The concentration of the superlattice channel at low temperature was 5.93?×?1015 cm-3 while those of the two dimensional hole and electron channels were 1.64?×?1011 cm-2 and 5.20?×?1011 cm-2. [ABSTRACT FROM AUTHOR]

A study analyzed molecular beam epitaxy grown InAs/GaSb superlattices, containing InSb-like interfacial layers by a combination of x-ray diffraction and structural refinement. The combined SUPREX//XRD experiments reveal that the absence of certain odd order satellite features in the x-ray data is due to asymmetric and inhomogeneous lattice strain.

The electrical properties of In0.25Ga0.75Sb/InAs superlattices designed for use as very long wavelength infrared detectors were studied with magnetic field dependent transport measurements and multicarrier analysis. Two electron channels and one hole channel were identified. The low concentration, high mobility electron channel was identified with conduction within the superlattice. Residual electron concentrations in the superlattice are found to be in the high 1010 cm-2 range with mobilities on the order of 40 000 cm²/V s. The other electron and hole channels have significantly lower mobilities with concentrations in the 1011 cm-2 range and can have a significant impact on the resistivity, carrier concentration, and mobility as measured at a single magnetic field value in conventional transport measurements. [ABSTRACT FROM AUTHOR]

Hemodynamic studies were performed to determine if blunting of vascular pressor responsiveness to vasoconstrictors during pregnancy may be due to impaired L-type voltage-dependent calcium channels (L-VDCC). Bay K 8644 (BAY), an L-VDCC agonist, was infused in pregnant and nonpregnant anesthetized rabbits (10, 20, 40, and 60 [micro]g/kg) and pregnant and nonpregnant conscious, chronically instrumented (conscious) rabbits (10, 25, and 50 [micro]g/kg). BAY infusions resulted in greater elevation of mean arterial pressure in both anesthetized pregnant (n = 6) vs. nonpregnant (n = 6) (P < 0.05) and conscious pregnant (n = 10) vs. nonpregnant (n = 10) rabbits (P < 0.05). Fractional increase over baseline of total peripheral resistance index was greater in pregnant (36 [+ or -] 5 to 78 [+ or -] 14%) vs. nonpregnant rabbits (14 [+ or -] 4 to 52 [+ or -] 6%) (P < 0.02). Cardiac output index did not differ. There was a single high-affinity L-VDCC antagonist aortic binding site with similar number and affinity in pregnant (n = 7) and nonpregnant (n = 7) rabbits. In conclusion, stimulation of L-VDCC induces greater pressor responses in pregnant rabbits with heightened peripheral vasoconstriction. This does not appear to be due to a change in L-VDCC receptor parameters. blood pressure; vascular reactivity; calcium channels; nifedipine

The first long-wave quantum-well infrared photodetectors that features lattice-matched n-doped InGaAlAs-InP materials system has been designed. Samples containing AlAs mole fractions of 0.0, 0.1 and 0.15 leads to cutoff wavelengths of 8.5, 13.3 and 19.4 micrometers, respectively. The measured intersubband photoresponse wavelength suggests the existence of a null conduction band offset for the In0.52Ga0.21Al0.27As-InP heterojunctions.