Genomewide search for dehydrated hereditary stomatocytosis (hereditary xerocytosis): mapping of locus to chromosome 16 (16q23-qter)

Dehydrated hereditary stomatocytosis, also known as "hereditary xerocytosis," is caused by a red blood cell-membrane defect characterized by stomatocytic morphology, increased mean corpuscular hemoglobin concentration, decreased osmotic fragility, increased permeability to the univalent cations Na+ and K+, and an increased proportion of phosphatidylcholine in the membrane. The clinical presentation is heterogeneous, ranging from mild to moderate hemolytic anemia associated with scleral icterus, splenomegaly, and choletithiasis. Iron overload may develop later in life. The disease is transmitted as an autosomal dominant trait. We recruited a large three-generation Irish family affected with DHS and comprising 23 members, of whom 14 were affected and 9 were healthy. Two additional, small families also were included in the study. The DNA samples from the family members were used in a genomewide search to identify, by linkage analysis, the DHS locus. After the exclusion of a portion of the human genome, we obtained conclusive evidence for linkage of DHS to microsatellite markers on the long arm of chromosome 16 (16q23-q24). A maximum two-point LOD score of 6.62 at recombination fraction .00 was obtained with marker D16S520. There are no recombination events defining the telomeric limit of the region, which therefore is quite large. No candidate genes map to this area.     

Experimental setup for lensless imaging via soft x-ray resonant scattering

We have developed a setup for measuring holographically formed interference patterns using an integrated sample-mask design. The direct space image of the sample is obtained via a two-dimensional Fourier transform of the X-ray diffraction pattern. We present the details of our setup, commenting on the influence of geometrical parameters on the imaging capabilities. As an example, we present and discuss the results of test experiments on a patterned Co film.     

A linear 60 GHz 65 nm-CMOS power amplifier realization and characterization for OFDM signal

A millimeter-wave Power Amplifier (PA) based on a 65nm CMOS technology from STMicroelectronics has been designed. The targeted feature is the unlicensed band around 60 GHz suitable for wireless personal area network application (WPAN). To optimize the linearity, the PA is designed under class A biasing to have an output compression point (OCP₁) close to its saturated Power (P _sat). S-parameters and large signal measurement results are demonstrated and compared with electromagnetic simulations. The PA offers a P _sat of 8.3 dBm, an OCP₁ of 6 dBm and a gain of 6.7 dB. The die area is 0.29 mm² with pads. Considering those results, one-tone simulations are not sufficient to characterize the linearity performances of the PA in its real conditions of use. Consequently, two-tone simulations are firstly performed. After, linearity figures of merit (FoM) are discussed applying an orthogonal frequency-division multiplexing (OFDM) modulated signal. The PA offers an adjacent channel power ratio (ACPR) of 15 dB and an error vector magnitude (EVM) of 20% at PA compression operating mode.     

Background Limited Performance of Long Wavelength Infrared Focal Plane Arrays Fabricated From M-Structure InAs–GaSb Superlattices

The recent introduction of a M-structure design improved both the dark current and R₀ A performances of type-II InAs-GaSb photodiodes. A focal plane array fabricated with this design was characterized at 81 K. The dark current of individual pixels was measured between 1.1 and 1.6 nA, 7 times lower than previous superlattice FPAs. This led to a higher dynamic range and longer integration times. The quantum efficiency of detectors without antireflective coating was 74%. The noise equivalent temperature difference reached 23 mK, limited only by the performance of the testing system and the read out integrated circuit. Background limited performances were demonstrated at 81 K for a 300 K background.     

Phase transformation in δ-Pu alloys at low temperature: An in situ microstructural characterization using X-ray diffraction

In order to investigate the martensitic transformation, an isothermal hold at −130 °C for 48 h was performed on a highly homogenized PuGa alloy. The modifications of the microstructure were characterized in situ thanks to a specific tool. This device was developed at the CEA-Valduc to analyze the crystalline structure of plutonium alloys as a function of temperature and more especially at low temperature using X-ray diffraction. The analysis of the recorded diffraction patterns highlighted that the martensitic transformation for this alloy is the result of a direct δ → α′ + δ phase transformation. Moreover, a significant Bragg’s peaks broadening corresponding to the δ-phase was observed. A microstructural analysis was made to characterize anisotropic microstrain resulting from the stress induced by the unit cell volume difference between the δ and α′ phases. The amount of α′-phase evolved was analyzed within the framework of the Avrami theory in order to characterize the nucleation process. The results suggested that the growth mechanism corresponded to a general mechanism where the nucleation sites were in the δ-grain edges and the α′-phase had a plate-like morphology.     

Efficient Assembly of Bridged β‐Ga2O3 Nanowires for Solar‐Blind Photodetection

An increasing number of applications using ultraviolet radiation have renewed interest in ultraviolet photodetector research. Particularly, solar‐blind photodetectors sensitive to only deep UV (<280 nm), have attracted growing attention because of their wide applicability. Among recent advances in UV detection, nanowire (NW)‐based photodetectors seem promising, however, none of the reported devices possesses the required attributes for practical solar‐blind photodetection, namely, an efficient fabrication process, a high solar light rejection ratio, a low photocurrent noise, and a fast response. Herein, the assembly of β‐Ga₂O₃ NWs into high‐performance solar‐blind photodetectors by use of an efficient bridging method is reported. The device is made in a single‐step chemical vapor deposition process and has a high 250‐to‐280‐nm rejection ratio (～2 × 10³), low photocurrent fluctuation (<3%), and a fast decay time (<<20 ms). Further, variations in the synthesis parameters of the NWs induce drastic changes in the photoresponse properties, which suggest a possibility for tuning the performance of the photodetectors. The efficient fabrication method and high performance of the bridged β‐Ga₂O₃ NW photodetectors make them highly suitable for solar‐blind photodetection.     

High-Performance Focal Plane Array Based on InAs–GaSb Superlattices With a 10-$mu{hbox {m}}$ Cutoff Wavelength

We report on the demonstration of a focal plane array based on Type-II InAs-GaSb superlattices grown on n-type GaSb substrate with a 50% cutoff wavelength at 10 mum. The surface leakage occurring after flip-chip bonding and underfill in the Type-II devices was suppressed using a double heterostructure design. The R₀A of diodes passivated with SiO₂ was 23 Omegamiddotcm² after underfill. A focal plane array hybridized to an Indigo readout integrated circuit demonstrated a noise equivalent temperature difference of 33 mK at 81 K, with an integration time of 0.23 ms.     

Stability of hydrogen incorporated in ZnO nanowires by plasma treatment

The stability of hydrogen in ZnO is studied using hydrogenated nanowires by plasma treatment. Enhanced near band edge UV emission and reduced defect level green emission is observed after hydrogen plasma treatment. Through thermal stability tests, this effect is found to be stable at room temperature and nearly stable up to ~500 K, but begins to deteriorate at higher temperature. The study of the irradiation stability of the hydrogen in ZnO nanowires shows that the hydrogen is stable under an electron beam with an accelerating voltage lower than 5 kV, but is not stable under 10 kV or under an intensive laser beam. The results could benefit the further understanding of the role of hydrogen in ZnO and light-emitting devices based on hydrogenated ZnO.     

New avenue for mid-UV-range detection of underivatized carbohydrates and amino acids in capillary electrophoresis

Capillary electrophoresis (CE) appeared as an interesting alternative to chromatographic methods for carbohydrate analysis, but it can be difficult to implement, because of the lack of easily ionizable functions and chromophore groups. Recently, a promising method was proposed by Rovio et al. for the CE separation under extremely high alkaline conditions of neutral carbohydrates under their alcoholate form and their direct UV detection [Rovio et al. Electrophoresis 2007, 28, 3129-3135; and Rovio et al. J. Chromatogr. A 2008, 1185, 139-144], which is claimed to be due to the absorption of enediolate at 270 nm. Even so, most of the detected compounds in Rovio's paper (for example, sucrose) cannot give such enediolate, lacking a carbonyl group. In this work, a deeper insight was paid to the understanding of detection mechanism. In effect, unusual detection phenomena were observed in comparing reducing and nonreducing carbohydrate behaviors, which pointed to the existence of photochemical reactions in the detection window. A more systematic study of the influence of many parameters (carbohydrate nature, electrolyte pH, residence time in the detection window, and capillary diameter) was undertaken. In addition to this, most of this work was performed under cathodic (reversed) electro-osmotic flow conditions (using Polybrene-modified capillaries), to obtain much faster separations than under Rovio's conditions. This study also opens up new avenues for the detection in mid-UV range of non-UV-absorbing compounds bearing reducing moieties, such as amino acids.