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Designing the next generation of high-resolution displays requires high pixel density per area and small pixel sizes without compromising the optical quality. Quantum dots (QDs) have been demonstrated as a promising material system for down-conversion of blue emission as they provide pure colors on the wide color gamut. However, for high color-conversion efficiency, the required QD film thickness has not been compatible with small pixel sizes. In this work, we develop a new type of freestanding QD-based color converter for efficient optical down-conversion from inorganic blue light-emitting diodes (LEDs) in a color-by-blue configuration. CdSe/ZnS core-shell QDs in a UV-curable polymer matrix are encapsulated within cavities formed by patterning and bonding a pair of patterned quartz substrates. By controlling the required QD thickness and the pixel size independently, we demonstrate freestanding monochrome red and green converters with small pixel sizes down to 5 × 5 μm

The utility of electrodiagnostic tests (EDx) for patients with a high pretest probability of idiopathic median neuropathy at the carpal tunnel (IMNCT) based on characteristic symptoms and signs is debated. Decision-making and care strategies could be informed by a better understanding of factors associated with surgeon recommendations for electrodiagnostic testing.Ninety-one upper-extremity surgeons participated in an online, survey-based experiment. Participants viewed 7 vignettes of patients with carpal tunnel syndrome, with the following factors randomized in each vignette: patient age, gender, magnitude of incapability, symptom intensity and the presence of nocturnal symptoms, palmar abduction weakness, and positive provocative tests results. We sought patient and surgeon factors associated with ordering EDx and surgeon-rated comfort with performing carpal tunnel release (CTR) without EDx.Surgeons recommended EDx for over half of the patient vignettes, with notable variation (median, 57%; interquartile range, 14-100), and felt relatively neutral, on average, offering CTR without EDx. Twenty-six (29%) out of 91 surgeons ordered EDx for all patient scenarios, and 18 surgeons (20%) did not order testing for any scenario. A lower likelihood of EDx was associated with older age and positive provocative tests results. Greater surgeon comfort offering CTR without EDx was associated with older patients, the presence of nocturnal symptoms, palmar abduction weakness, and positive provocative tests results.Upper-extremity surgeons are neutral regarding diagnosing IMNCT based on electrodiagnostic evidence of pathology and are relatively more comfortable offering surgery without EDx in older patients that present with key aspects of carpal tunnel syndrome. There is notable variation in care, with half of all surgeons always or never ordering EDx.Future studies can investigate whether a treatment strategy offering surgery to patients with a high pretest probability of IMNCT and only using EDx in intermediate probability scenarios can limit use of testing without affecting patient health.

Integration of Si-CMOS and III-V compound semiconductors (with device structures of either InGaAs HEMT, InGaP LED, GaAs HBT, GaN HEMT or InGaN LED) on a common Si substrate is demonstrated. The Si-CMOS layer is temporarily bonded on a Si handle wafer. Another III-V/Si substrate is then bonded to the Si-CMOS containing handle wafer. Finally, the handle wafer is released to realize the Si-CMOS on III-V/Si substrate. For GaN LED or HEMT on Si substrate, additional wafer bonding step is required to replace the fragile Si (111) substrate after high temperature GaN growth with a new Si (001) wafer to improve the robustness of the GaN/Si wafers. Through this substrate replacement step, the bonded wafer pair can survive the subsequent processing steps. The monolithic integration of Si-CMOS + III-V devices on a common Si platform enables new generation of systems with more functionality, better energy efficiency, and smaller form factor.

AlN/GaN metal–insulator–semiconductor high electron mobility transistors (MISHEMTs) on silicon substrate using in situ SiN as gate dielectric were fabricated and their RF power performance at mobile system-on-chip (SoC) compatible voltages was measured. At a mobile SoC-compatible supply voltage of V d = 3.5 V/5 V, the 90 nm gate-length AlN/GaN MISHEMTs showed a maximum power-added efficiency of 62%/58%, a maximum output power density (P outmax) of 0.44 W mm−1/0.84 W mm−1 and a linear gain of 20 dB/19 dB at the frequency of 5 GHz. These results suggest that the in situ-SiN/AlN/GaN-on-Si MISHEMTs are promising for RF power amplifiers in 5G mobile SoC applications.

Metamorphic epitaxy offers the possibility of growing devices on wafers composed of different materials that might be larger than the native bulk substrates for a potential cost-reduction of III–V components; this is especially important when native substrates with desired lattice constants are not available. This article reviews the concepts of metamorphic epitaxy of III–V compound semiconductor materials and examines how they have been applied to the development of advanced transistor devices. These metamorphic devices are expected to be a key enabler of future heterogeneous integrated circuits in which Si and III–V devices are monolithically integrated on a wafer scale using complementary metal oxide semiconductor-like process flows.

Two approaches for metalorganic chemical vapor deposition (MOCVD)-grown compositionally graded metamorphic buffers on 6° offcut bulk GaAs were investigated. The first approach consisted of tandem graded layers of InGaAs and InGaP with compositional grading of the In concentration. This tandem approach was found to be necessary because phase separation in the InGaAs alloys leads to surface roughening and high threading dislocation density when grading to lattice constants greater than that of In 0.30 Ga 0.70 As. An In x Ga 1− x As graded buffer was grown at 700 °C for low In concentration ( X In =0–0.10) and then the growth temperature was decreased to 450 °C for high In concentration ( X In =0.10–0.30) to suppress the phase separation. The growth temperature was then increased to 650 °C and the graded In y Ga 1− y P system was implemented to continue grading the lattice constant from In 0.30 Ga 0.70 As to InP, which allowed us to achieve InP on 6° offcut GaAs with a threading dislocation density of 7.9×10 6 cm −2 and an RMS surface roughness of 33.0 nm on a 40 μm×40 μm AFM scale. The second approach used GaAsSb alloys with compositional grading of the Sb concentration. Graded mixed-anion GaAsSb alloys grown at 575 °C did not exhibit phase separation, resulting in high quality InP lattice constant films on GaAs without the need to transition to another material system for compositional grading. We demonstrated a GaAsSb alloy on GaAs (with a grading rate of 1.06% strain/μm) lattice-matched to InP with a threading dislocation density of 4.7×10 6 cm −2 and a roughness of 7.4 nm on a 40 μm×40 μm AFM scale. It was further demonstrated that the threading dislocation density of the GaAsSb graded buffer can be lowered to 2.7×10 6 cm -2 with a slower grading rate (0.64% strain/μm).

Integration of Si-CMOS and III-V compound semiconductors (with device structures of either InGaAs HEMT, AlGaInP LED, GaN HEMT or InGaN LED) on a common Si substrate is demonstrated. The Si-CMOS layer is temporarily bonded on a Si handle wafer. Another III-V/Si substrate is then bonded to the Si-CMOS containing handle wafer. Finally, the handle wafer is released to realize the Si-CMOS on III-V/Si substrate. For GaN HEMT or LED on Si substrate, additional wafer bonding step is required to replace the fragile Si (111) substrate after high temperature GaN growth with a new Si (001) wafer to improve the robustness of the GaN/Si wafers. Through this substrate replacement step, the bonded wafer pair can survive the subsequent processing steps. The monolithic integration of Si-CMOS + III-V devices on a common Si platform enables new generation of systems with more functionality, better energy efficiency, and smaller form factor.

We have investigated the use of a continuous, linear grading scheme for compositionally graded (metamorphic) In x Ga 1− x As buffers on GaAs grown using MOCVD, which can be used as virtual substrates for optical emitters operating at wavelengths >1.2 μm. Graded buffer quality, as quantified by threading dislocation density (TDD) measurements, was investigated for a range of different graded buffer designs and growth parameters. The best graded buffers obtained had TDD 4 cm −2 , at a final composition of x =0.346. MOCVD reactor configuration was found to play a key role in obtaining the best graded buffers. Photoluminescence (PL) measurements were carried out on doped and undoped quantum-well separate confinement heterostructures (QW-SCH) that were re-grown on these buffers. The results showed that these buffers can serve as high-quality strain-relaxed templates for optoelectronic devices operating in the 1.2–1.5 μm wavelength region, and it is expected that with further refinement, high-quality virtual substrates can be made that will allow operation even beyond 1.6 μm.

A grazing incidence X-ray diffraction technique was developed to characterize the effectiveness of the coating of the solid particles by the binder in energetic formulations and was used in conjunction with scanning electron microscopy, traditional wide-angle X-ray diffraction, and specific gravity measurements to probe the microstructure of PAX-12 granules. The grazing incidence X-ray technique was applied to granules formed upon slurry coating and indicated different X-ray scattering characteristics for high- and low-sensitivity granules, suggesting significant differences in the distribution of the binder at the surface of the granules. The granules were made by slurry-coating crystals of epsilon CL-20 with cellulose acetate butyrate, a binder, and bis-(2,2 dinitropropyl acetal/formal), a plasticizer. Granules with high sensitivity to impact and friction were shown to have an interior that was relatively porous and that consisted of uncoated CL-20 crystals. Their surface had regions with a thick layer ...

During last few decades, there have been tremendous progress in the development of III-V based and III-Nitride based devices, namely High Electron Mobility Transistors (HEMT) and Light Emitting Diodes (LEDs). Research interest has recently shifted towards III-V compound semiconductor epitaxy on large diameter (200 mm) Si substrates in order to realize III-V-on-Si and CMOS integration. Due to large lattice and thermal mismatch between III-V and Si materials, e g. GaN-on-Si wafers experience large internal stresses and significant wafer bow. The wafer bow is severe for large wafers (for a given radius of curvature, the wafer bow increases by 125% for 150 mm and 300% for 200 mm diameter wafers compared to 100 mm wafers). This results in wafer fragility issues, as well as difficulties in subsequent handling and processing of such wafers. These issues are typically addressed using thicker Si substrates and careful design of buffer layers. While there are many experimental efforts to overcome these challenges, there are only limited reports that try to properly explain and understand the mechanism of wafer curvature. An appropriate theoretical model which predicts the final wafer curvature for given epilayer designs would greatly improve our ability to design optimal buffer and device layers. There are so far two main models for epitaxial multilayers which relate the wafer curvature to the strain state and the material properties of each layer. Ohlsen et al. (J. App. Phys. 1977) derived an analytical expression for the stress in each layer and the final wafer curvature for a given layer stack. This model however does require one to define strain states in each layer which is not straightforward to predict prior to the actual hetero-epitaxy of complex layers with large misfit dislocation densities such as in the GaN-on-Si system. Usher et al. (Phys. Rev. B 2003) proposed an atomistic approach for analyzing pseudo-morphic multi-layer structures, and were able to provide a closed form equation for radius of curvature. However, none of the reports have explicitly considered the thermal strain in the calculation. In this presentation we would address these limitations and provide a complete description of the wafer curvature including the effects of both lattice mismatch and coefficient of thermal expansion mismatch. We extend the atomistic approach to calculate the radius of curvature for non-pseudomorphic systems like III/V-on-Si systems. The density of misfit dislocations at each interface is used as a parameter to define the effective lattice constant of partially relaxed epilayers at the interface. Subsequently the lattice constant at any point in each layer is defined with respect to the interface lattice constant and is used to calculate the strain. Then the total strain energy of the resulting system is calculated as a function of system curvature, with the minimum energy solution corresponding to the predicted final curvature of the wafer. For better accuracy each epitaxial layer may be divided to separate sublayers with individual misfit dislocation density values. For illustration GaN-3xAlGaN-AlN-Si system was considered and radius of curvature was predicted. The accuracy of the model depends on the accuracy with which the misfit dislocation density is known. Experimental techniques like TEM and electron beam induced current (EBIC) can be used to estimate or quantify the number of dislocated atoms. Finally, we will include the thermal effect within the atomistic approach to be able to predict in-situ curvature of III/V-on-Si systems which will be helpful in designing the growth experiments for various devices.

We report an above-band-gap radiative transition in the photoluminescence spectra of single crystalline Ge in the temperature range of 20~296 K. The temperature-independence of the peak position at ~0.74 eV is remarkably different from the behavior of direct and indirect gap transitions in Ge. This transition is observed in n-type, p-type, and intrinsic single crystal Ge alike, and its intensity decreases with the increase of temperature with a small activation energy of 56 meV. Some aspects of the transition are analogous to III-V semiconductors with dilute nitrogen doping, which suggests that the origin could be related to an isoelectronic defect.

The effects of many-body coulomb interaction and non-parabolicity on optical gain of terahertz quantum cascade lasers are investigated based on the density-matrix model. The results show that many-body interaction and non-parabolicity effect all red-shift the gain spectrum and reduces the peak value. Furthermore, the interplay of various many-body effects that reveals the optical spectral redshift and reduction are mainly caused by the depolarization terms. The proposed model provides a comprehensive picture of optical properties of THz QCLs, not only enhancing our in-depth understanding of optical gain, but also enabling an accurate prediction of the device performance.

Addition of Me2GeCl2 to Li+ [(η5-C5H5)Re(NO)(PPh3)] gives the chiral rhenium dimethylchlorogermyl complex (η5-C5H5)Re(NO)(PPh3)(GeMe2Cl) (92%), which reacts with LiAlH, and Me3SiOTf to yield (n5-C5H5)Re(NO)-(PPh3)(GeMe2H) (74%) and (η5-C5H5)Re(NO)(PPh3)(GeMe2OTf) (3; 94%), respectively. Reactions of 3 and halide salts give (η5-C5H5)Re(NO)-(PPh3)(GeMe2X) (X=F, Br, I; 81–83%). All compounds exhibit two 1H/ 13C NMR signals for the diastereotopic GeMe 2 groups at ambient temperature, except 3 for which coalescence occurs at 211 K (Δ≠=9.6 ± 0.2 kcal/mol). This is interpreted as indicating a rapid equilibrium with the dimethylgermylene complex [(n5-C5H5)Re(NO)(PPh3)(=GeMe2)]+ TfO−.

Reaction of Me2GaCl and LiCCSiMe3 or R2GaCl (R  Me, tBu) and LiCCPh (benzene, 70°C) gives [Me2GaCCSiMe3]2 and [R2GaCCPh]2 in 62%, 58%, and 71% yields, respectively. The gallium acetylides were characterized by IR, Raman, and NMR (1H, 13C, 13C{1H}) spectroscopy. Reactions of the dimethylgallium acetylides and phosphines (R2PH; R  Et, iPr) (toluene, 110-20°C) give HCCSiMe3 or HCCPh and the corresponding dimethylgallium dialkylphosphides [Me2GaPR2]n (R  Et, n = 3, iPr, n = 2).

Reactions of (η5-C5H5)Re(NO)(PPh3)(SiMe2H) (1) and CHCl3, CBr4, and CHI3 give halosilyl complexes (η5-C5H5)Re(NO)-(PPh3)(SiMe2X) [X = Cl (2), Br (3), I (4); 66–84%]. Addition of Me3SiOTf to 2 gives triflate (η5-C5H5)Re(NO)(PPh3)(SiMe2OTf) (5; 97%), which in turn reacts with (Me2N)3S⊕ [SiMe3F2]⊖ to give (η5-C5H5)Re(NO)(PPh3)(SiMe2F) (6; 77%). Reaction of 5 and pyridine gives the base-stabilized silylene complex [(η5-C5H5)Re(NO)(PPh3){SiMe2(NC5H5)}]⊕ TfO⊖ (7; 84%). CH2Cl2 solutions of (η5-C5H5)Re(NO)(PPh3)(CH3) (8) or 2 and Lewis acids are studied by IR and NMR. As assayed by IR, 8/ECl3 solutions (E = B, Al) show ReNO–ECl3 (major) and Re–ECl3 (minor) adducts. Solutions of 2/BCl3 show analogous adducts (-78°C), and in the presence of excess BCl3 (η5-C5H5)Re-(NO–BCl3)(PPh3)(SiMe2Cl) (11) crystallizes. Solutions of 2/AlCl3 show uncomplexed 2 and Re–AlCl3 (major) and ReNO–AlCl3 (minor) adducts. In contrast to 2–7 and 2/BCl3, 1H- and 13C-NMR spectra of 2/AlCl3 suggest an equilibrium with the base-free silylene complex [(η5-C5H5)Re(NO)(PPh3)-( = SiMe2)]⊕ X⊖.

Reaction of Me2GaCl and LiCCSiMe3 or R2GaCl (R  Me, tBu) and LiCCPh (benzene, 70°C) gives [Me2GaCCSiMe3]2 and [R2GaCCPh]2 in 62%, 58%, and 71% yields, respectively. The gallium acetylides were characterized by IR, Raman, and NMR (1H, 13C, 13C{1H}) spectroscopy. Reactions of the dimethylgallium acetylides and phosphines (R2PH; R  Et, iPr) (toluene, 110-20°C) give HCCSiMe3 or HCCPh and the corresponding dimethylgallium dialkylphosphides [Me2GaPR2]n (R  Et, n = 3, iPr, n = 2).

Reactions of Li + [η 5 -C 5 H 5 )Re(NO)(PPh 3 )] − with Ph 3 GeCl and Ph 2 GeCl 2 (THF, −78°C) give germyl complexes (η 5 -C 5 H 5 )Re(NO)(PPh 3 )(GePh 3 ) and (η 5 -C 5 H 5 )Re(NO)(PPh 3 )(GePh 2 Cl). Reactions with LiAlH 4 and Me 3 SiOTf give (η 5 -C 5 H 5 )Re(NO)(PPh 3 )(GePh 2 H) and (η 5 -C 5 H 5 )Re(NO)(PPh 3 )(GePh 2 OTf)

Reactions of (η5-C5H5)Re(NO)(PPh3)(SiMe2H) (1) and CHCl3, CBr4, and CHI3 give halosilyl complexes (η5-C5H5)Re(NO)-(PPh3)(SiMe2X) [X = Cl (2), Br (3), I (4); 66–84%]. Addition of Me3SiOTf to 2 gives triflate (η5-C5H5)Re(NO)(PPh3)(SiMe2OTf) (5; 97%), which in turn reacts with (Me2N)3S⊕ [SiMe3F2]⊖ to give (η5-C5H5)Re(NO)(PPh3)(SiMe2F) (6; 77%). Reaction of 5 and pyridine gives the base-stabilized silylene complex [(η5-C5H5)Re(NO)(PPh3){SiMe2(NC5H5)}]⊕ TfO⊖ (7; 84%). CH2Cl2 solutions of (η5-C5H5)Re(NO)(PPh3)(CH3) (8) or 2 and Lewis acids are studied by IR and NMR. As assayed by IR, 8/ECl3 solutions (E = B, Al) show ReNO–ECl3 (major) and Re–ECl3 (minor) adducts. Solutions of 2/BCl3 show analogous adducts (-78°C), and in the presence of excess BCl3 (η5-C5H5)Re-(NO–BCl3)(PPh3)(SiMe2Cl) (11) crystallizes. Solutions of 2/AlCl3 show uncomplexed 2 and Re–AlCl3 (major) and ReNO–AlCl3 (minor) adducts. In contrast to 2–7 and 2/BCl3, 1H- and 13C-NMR spectra of 2/AlCl3 suggest an equilibrium with the base-free silylene complex [(η5-C5H5)Re(NO)(PPh3)-( = SiMe2)]⊕ X⊖.

Described in this paper are ongoing research efforts at ATK Thiokol on new formulations of gun propellants and explosives containing nano-sized materials. Funding for this work was provided both internally and by ARDEC. The nano-material properties as well as selected properties of intermediate compositions are reported.The explosives section of this paper focuses on the theoretical evaluation of nano-aluminum in explosives. The theoretical cylinder expansion energy of two common aluminized explosives, PAX-3 and PAX-28, are examined. The comparison examines the effect of aluminum content in small aluminum particles on metal pushing performance at V/V0 = 6.5.ATK Thiokol and TACOM-ARDEC have teamed together to study the effect of nano-sized materials on advanced ETPE gun propellants. The gun propellant section of this paper focuses on the impact of nano-sized additives, specifically TiO2 and aluminum, on selected ETPE propellants. The safety properties of the nano-aluminum and nano-TiO2 analogs of two previously developed gun propellants, TGD-031 and TGD-035, are presented.

The novel antimony source compound di-isopropylantimony hydride, (i-Pr)2 was synthesized and evaluated for use as a volatile Sb-source compound for low temperature growth of Sb-containing semiconductor materials. (i-Pr)2SbH was pyrolyzed in a horizontal atmospheric pressure organometallic vapor phase epitaxy (OMVPE) reactor using Arand H2 as carrier gases. The gaseous exhaust products were analyzed by a residual gas analyzer. Complete pyrolysis of (i-Pr)2SbH in our OMVPE reactor occursaround 300°C and 350°C in Ar and H2, respectively. A comparison between the pyrolysis temperatures and pyrolysis byproducts with respect to a proposed decomposition mechanism of (i-Pr)2SbH is presented. Sb films were grown on Si(100) andSi(111) as low as 200° C. The Sb films were analyzed by Auger and X-ray diffraction. These polycrystalline Sb films were free of detectable carbon by AES. X-ray diffraction data indicated that these Sb films were highly oriented in the [000L] direction.

New dialkylgallium dialkylphosphide compounds having the formula [(t- Bu)(R)GaPR'2]n (R = t-Bu, Me3SiC=C; R' = t-Bu, i-Pr, Et; n = 1, 2) were recently prepared and characterized. When R = R' = t-Bu, the compound is a low melting, monomeric solid. The other compounds are dimeric solids with the unsym-metrical acetylides occurring as cis and trans isomers. Polycrystalline gallium phosphide was deposited from these sources on silicon atlow pressure (0.05–0.1 Torr) and low temperature (350–600 °C) in a horizontal OMVPE reactor. The film growth was monitored by a residual gas analyzer and the by-products were trapped (N2(1)) to be later analyzed by 1H and 13C NMR. The deposited films were characterized by Raman spectroscopy, X-ray powder diffraction, and Auger emission spectroscopy.

Highly tensile-strained Ge thin films and quantum dots have the potential to be implemented for high mobility metal-oxide-semiconductor field-effect transistor channels and long-wavelength optoelectronic devices. To obtain large tensile strain, Ge has to be epitaxially grown on a material with a larger lattice constant. We report on the growth of tensile-strained Ge on relaxed InxGa1−xAs epitaxial templates by metal-organic chemical vapor deposition. To investigate the methods to achieve high quality Ge epitaxy on III–V semiconductor surfaces, we studied Ge growth on GaAs with variable surface stoichiometry by employing different surface preparation processes. Surfaces with high Ga-to-As ratio are found to be necessary to initiate defect-free Ge epitaxy on GaAs. With proper surface preparation, tensile-strained Ge was grown on relaxed InxGa1−xAs with a range of In content. Low growth temperatures between 350 and 500 °C suppress misfit dislocation formation and strain relaxation. Planar Ge thin films with ...

9549 Background: Osteosarcoma (OS) is the most common bone cancer, with a peak incidence in mid-adolescence. OS outcome is poor for metastatic or recurrent disease ( No significant financial relationships to disclose.

Philadelphia chromosome-positive ALL (Ph+ALL) strikes older children and adults, is difficult to treat and often has poor outcomes with conventional therapies. Tremendous advances have been made in other cancers through identification of essential signaling molecules that can be inhibited by small molecule medicines. ERBB proteins are such targets for several adult carcinomas, including breast and lung cancer. Expression of one member of the ERBB family, Her-2, is associated with chemotherapy resistance in one report of adult B-ALL. We examined the expression, activation status and contribution to growth and survival of ERBB receptors in Ph+ALL cell lines Z33, Z119 and Z181. Phosphorylated Her-2 was detected by western blot in all 3 lines, as was trace amounts of Her-3. Western-blot identified expression of the p80 form of Her-4 in Z119, which correlated with flow cytometry assessment of Her-4. Expression in Z33 of EGFR, detected by western blot, correlated with down-regulation of both EGFR and Her-2 from the cell surface, as assessed by flow cytometry. Internalization of EGFR homo- and hetero-dimers is associated with receptor phosphorylation and active signaling. To assess the physiologic importance of ERBB signaling in Ph+ALL, cells were cultured in the pan-ERBB inhibitor CI-1033 (Pfizer Global Research and Development), which is specific for ERBB family receptors in tissue culture up to 20 μM concentrations. All lines demonstrated reduced cell yield after CI-1033 exposure, with average IC50 of 0.783 for Z119, 1.178 for Z181 and 1.737 for Z33. The increased sensitivity of Z119 to CI-1033 correlated with an increased rate of apoptosis: 3 μM CI-1033 caused a 26% increase in the fraction of sub-diploid Z119 cells at 24 hours, compared to 13% for Z181 and 16% for Z33. Higher sensitivity to ERBB inhibition also correlated with growth factor resistance, since Z33 and Z181 are dependent upon autocrine GM-CSF for growth while Z119 grows independent of known autocrine secretion of hematopoietic growth factors. These data suggest that Ph+ALL cells may acquire GM-CSF independence by relying more on ERBB-derived signals, since these receptors are capable of activating similar second messenger pathways. Our data suggest that, surprisingly, the ERBB family of receptor tyrosine kinases are intact and functioning in Ph+ALL, and inhibition of these signals may provide benefit to Ph+ALL patients, either in combination with imatinib or in patients who develop imatinib resistance.

The debate between the skin testing allergist and the in vitro testing allergist goes on. Clearly, the in vitro methods of allergy testing are here to stay. In vitro testing is less limiting and offers a number of advantages to both the allergist and the patient.

Reaction of Li+[(η5-C5H5)Re(NO)(PPh3)]− with Ph3GeCl and Ph2GeCl2 (THF, −75°C) gives germyl complexes (η5-C5H5)Re(NO)(PPh3)(GePh3) (84%) and (η5-C5H5) Re(NO)(PPh3)(GePh2Cl) (3, 82%), respectively. Reaction of 3 and (CH3)3SiOTf gives (η5-C5H5)Re(NO)(PPh3)(GePh2OTf) (4, 82%). Several properties show the triflate substituent in 4 to be extremely labile. First, reaction of 4 and pyridine to give [(η5- C5H5)Re(NO)(PPh3)(GePh2NC5H5)]+TfO− (5) is complete in

Le succes de la mastoidotympanoplastie repose non seulement sur l'ablation meticuleuse du cholesteatome et d'autres maladies mais aussi sur le «traitement des tissus mous». Une bonne meatoplastie est essentielle