We report the integration of a ferroelectric (FE) silicon-doped hafnium oxide material in ferroelectric field-effect transistor (FeFET) devices fabricated with an optimized interfacial layer in a ...gate-first scheme. The effect of increasing the permittivity (k) value of the interface layer on the performance of the metal-ferroelectric-insulator-semiconductor (MFIS)-FE-HfO 2 FeFET is studied in terms of its switching characteristics, endurance, and retention. In contrast to the previous work, the FE Si:HfO 2 -integrated FeFET devices show a low-power operation capability as well as an improved endurance characteristics without jeopardizing high-temperature retention. The utilization of an optimized SiON interface layer for MFIS-HfO 2 FeFET stack is discussed, and the improvements are outlined with reference to a standard low-k SiO 2 interface.
Single-Molecule Recognition Imaging Microscopy Stroh, C.; Wang, H.; Bash, R. ...
Proceedings of the National Academy of Sciences - PNAS,
08/2004, Letnik:
101, Številka:
34
Journal Article
Recenzirano
Odprti dostop
Atomic force microscopy is a powerful and widely used imaging technique that can visualize single molecules and follow processes at the single-molecule level both in air and in solution. For maximum ...usefulness in biological applications, atomic force microscopy needs to be able to identify specific types of molecules in an image, much as fluorescent tags do for optical microscopy. The results presented here demonstrate that the highly specific antibody-antigen interaction can be used to generate single-molecule maps of specific types of molecules in a compositionally complex sample while simultaneously carrying out high-resolution topographic imaging. Because it can identify specific components, the technique can be used to map composition over an image and to detect compositional changes occurring during a process.
The Compact Reconnaissance Imaging Spectrometer for Mars (CRISM) is a hyperspectral imager on the Mars Reconnaissance Orbiter (MRO) spacecraft. CRISM consists of three subassemblies, a gimbaled ...Optical Sensor Unit (OSU), a Data Processing Unit (DPU), and the Gimbal Motor Electronics (GME). CRISM's objectives are (1) to map the entire surface using a subset of bands to characterize crustal mineralogy, (2) to map the mineralogy of key areas at high spectral and spatial resolution, and (3) to measure spatial and seasonal variations in the atmosphere. These objectives are addressed using three major types of observations. In multispectral mapping mode, with the OSU pointed at planet nadir, data are collected at a subset of 72 wavelengths covering key mineralogic absorptions and binned to pixel footprints of 100 or 200 m/pixel. Nearly the entire planet can be mapped in this fashion. In targeted mode the OSU is scanned to remove most along‐track motion, and a region of interest is mapped at full spatial and spectral resolution (15–19 m/pixel, 362–3920 nm at 6.55 nm/channel). Ten additional abbreviated, spatially binned images are taken before and after the main image, providing an emission phase function (EPF) of the site for atmospheric study and correction of surface spectra for atmospheric effects. In atmospheric mode, only the EPF is acquired. Global grids of the resulting lower data volume observations are taken repeatedly throughout the Martian year to measure seasonal variations in atmospheric properties. Raw, calibrated, and map‐projected data are delivered to the community with a spectral library to aid in interpretation.
A dedicated, novel, multichannel transmit/receive (Tx/Rx) coil array was designed, simulated, and tested for cardiac magnetic resonance imaging (cMRI) of pigs at 7 T. The cardiac array was composed ...of 16 elements with physically independent anterior and posterior parts. The array was connected to the MRI scanner in the parallel transmit (pTx) mode forming an 8-channel transmit and 16-channel receive (8Tx/16Rx) coil configuration. The anterior array was composed of four central octagonal elements, which were decoupled using a common central ring (CCR) and shared decoupling capacitors. The surrounding four triangular elements were decoupled from the central four elements using gaps and capacitive decoupling. In total, the eight elements of the anterior array resembled a coil with a symmetrical circular shape. Due to the advantageous arrangement of the elements in conjunction with the novel decoupling method of a CCR, the coupling between the adjacent loop elements was minimized. The posterior array was built using a <inline-formula> <tex-math notation="LaTeX">4 \times 2 </tex-math></inline-formula> standard rectangular, symmetric element configuration. The dedicated cardiac array was tested in phantom and in ex vivo MR measurements with a female pig of 46 kg. The dedicated coil array enhanced the signal-to-noise ratio (40 ± 27) in ex vivo measurements of the pig heart by about three times compared to a coil prototype for cardiac human imaging (11.8 ± 7). High-resolution, ex vivo cardiac images were acquired with an in-plane resolution of up to 0.3 mm <inline-formula> <tex-math notation="LaTeX">\times0.3 </tex-math></inline-formula> mm using the dedicated pig coil array. The novel cardiac array supports parallel imaging with an acceleration factor (R) of 4 without increasing the mean <inline-formula> <tex-math notation="LaTeX">g </tex-math></inline-formula>-factor within the heart region beyond 1.15.
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•The antisymmetric array enhanced the SNR by about two-fold compared to the rectilinear array design.•The novel design demonstrated good decoupling between all neighboring elements of ...the entire array.•Improved control of the B1+ field distributions using RF shimming was demonstrated in EM-simulations.•The antisymmetric array enabled the application of GRAPPA acceleration factor R = 4 with mean g-factor ± SD of only 1.13 ± 0.07.•High resolution ex-vivo images were acquired using standard clinical protocols (in-plane resolution = 0.3mm × 0.3mm).
The design, simulation, assembly and testing of a novel dedicated antisymmetric transmit/receive (Tx/Rx) coil array to demonstrate the feasibility of cardiac magnetic resonance imaging (cMRI) in pigs at 7 T was described. The novel antisymmetric array is composed of eight elements based on mirrored and reversed loop orientations to generate varying B1+ field harmonics for RF shimming. The central four loop elements formed together a pair of antisymmetric L-shaped channels to allow good decoupling between all neighboring elements of the entire array. The antisymmetric array was compared to a standard symmetric rectilinear loop array with an identical housing dimension. Both arrays were driven in the parallel transmit (pTx) mode forming an 8-channel transmit and 16-channel receive (8Tx/16Rx) coil array, where the same posterior array was combined with both anterior arrays. The hardware and imaging performance of the dedicated cardiac arrays were validated and compared by means of electromagnetic (EM) simulations, bench-top measurements, phantom, and ex-vivo MRI experiments with 46 kg female pig. Combined signal-to-noise ratio (SNR), geometry factor (g-factor), noise correlation maps, and high resolution ex-vivo cardiac images were acquired with an in-plane resolution of 0.3 mm × 0.3 mm using both arrays. The novel antisymmetric array enhanced the SNR within the heart by about two times and demonstrated good decoupling and improved control of the B1+ field distributions for RF shimming compared to the standard coil array. Parallel imaging with acceleration factor (R) up to 4 was possible using the novel antisymmetric coil array while maintaining the mean g-factor within the heart region of 1.13.
Background:
Expressed emotion is the affective attitudes and behaviors of an individual toward another. In this preliminary study, we described expressed emotion among caregivers of children with ...asthma living in low-income urban area and evaluated its association with child asthma control.
Methods:
Forty-one children (90.2% African American/Black) and their caregivers participated. Measures included the Childhood Asthma Control Test and the Five-Minute Speech Sample coded for overall expressed emotion, emotional over-involvement, and criticism.
Results:
Most caregivers were rated borderline (31.7%) or high (48.8%) for expressed emotion, borderline (31.7%) or high (39.0%) for emotional overinvolvement, and low for criticism (73.2%). The association between criticism and asthma control neared statistical significance
U
(
N
low
= 30,
N
B/high
= 11) = 100,
z
= −1.922,
P
= 0.055.
Conclusion:
Findings suggest an examination into expressed emotion coding procedures for caregivers in low-income urban areas, and culturally specific adaptations may be necessary. Future research should confirm findings in a larger sample and consider how parental criticism affects children's asthma management.
Abstract Septorhinoplasty is a commonly performed procedure for facial aesthetics and obstructed nasal breathing. There have been only four reported cases of methicillin-resistant Staphylococcus ...aureus (MRSA)-associated postoperative complications reported in the literature across all specialties. In this article, we report a case of MRSA-associated infection following an uncomplicated septorhinoplasty. Risk stratification and outcome of treatment are described, followed by a review of the current literature. We discuss the epidemiology of MRSA colonization, prophylactic use of antibiotics in septorhinoplasty, previously reported MRSA-associated septorhinoplasty infections, and management of complications. There are no current standards for MRSA decolonization prior to septorhinoplasty. Finally, we offer recommendations for high-risk MRSA patients undergoing septorhinoplasty and considerations for treatment of MRSA infections should they occur following septorhinoplasty.
We study the coalescence of two bound energy eigenstates embedded in the continuous spectrum of a real Hamiltonian HW and the singular point produced by this coalescence. At the singular point, the ...two unnormalized Jost eigenfunctions are no longer linearly independent but coalesce to give rise to a bound state eigenfunction embedded in the continuum. We disturb the potential VW by means of a truncation; this perturbation breaks the singular point in two resonances. The phase shift shows a jump of magnitude 2π and the shape of the cross section shows two inverted peaks; this behaviour is due to the interference between the two nearly degenerate resonances and the background component of the Jost function.
Three parallel transmission chains of measles virus (MV) variant ‘D8-Villupuram’ (D8-V) originated from two coinciding international mass gathering (MG) events in Rimini, Italy, in June 2011. MV D8-V ...was independently introduced into Germany by two unvaccinated persons, and into Slovenia by one unvaccinated person who had attended these events. Secondary spread of D8-V was restricted to two generations of transmission in Slovenia as well as in Germany where the virus was further disseminated at another MG. Serological and epidemiological investigation of the D8-V-associated German and Slovenian cases revealed different antibody responses and age distributions. Primary infected young persons between 11 and 27 years-old were affected in Germany, whereas the group of Slovenian cases comprised adults aged from 28 to 47 years and a high proportion (9/14; 64%) of patients with secondary vaccine failure (SVF). Our study demonstrates that monitoring of MV transmission chains in an international context and adequate serological investigation of cases with remote vaccination can contribute to identify susceptibility gaps.
Nucleosomes are a major impediment to regulatory factor activities and therefore to the operation of genomic processes in eukaryotes. One suggested mechanism for overcoming in vivo nucleosomal ...repression is factor-mediated removal of H2A/H2B from nucleosomes. Using nucleosomes labeled internally with FRET fluorophores, we previously observed significant, DNA sequence-dependent variation in stability and dynamics under conditions (subnanomolar concentrations) reported to produce H2A/H2B release from nucleosomes. Here, the same analytical approaches are repeated using 5S and MMTV-B nucleosomes containing FRET labels that monitor the terminal regions. The results show that stability and dynamics vary significantly within the nucleosome; terminally labeled constructs report significantly reduced stability and enhanced DNA dynamics compared to internally labeled constructs. The data also strongly support previous suggestions (1) that subnanomolar concentrations cause H2A/H2B release from nucleosomes, including the 5S, and (2) that stabilities in the internal regions of 5S and two promoter-derived nucleosomes (MMTV-B, GAL10) differ. Sequence-dependent nucleosome stability/dynamics differences could produce inherent variations in the accessibility of histone-associated DNA in vivo. Such intrinsic variation could also provide a mechanism for producing enhanced effects on specific nucleosomes by processes affecting large chromatin regions, thus facilitating the localized targeting of alterations to nucleosomes on crucial regulatory sequences. The results demonstrate clearly the importance of studying physiologically relevant nucleosomes.
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