The Differences between the InyGa1−yAs/GaAs Interface and GaAs/InyGa1−yAs Interface in Superlattice over a InxGa1−xAs (x

1996 ◽  
Vol 442 ◽  
Author(s):  
X.J Wang ◽  
L.X Zheng ◽  
Z.B Xiao ◽  
Z.P Zhang ◽  
X.W Hu ◽  
...  

AbstractThe InyGa1−yAs/GaAs superlattice on InxGa1−x.As (x<y) buffer layer was grown by MOCVD. The well layer is under compressive strain and the barrier layer is under tensile strain. However, both layers do not exceed the calculated critical value based on the M−yAs interface was smoother than the InyGa1−yAs/GaAs interface; the Indium composition gradual region at the GaAs/InyGal1−yAs interface was narrower than that at the InyGa 1−yAs/GaAs interface; in InyGa1−yAs alloy layer, the Indium composition near the GaAs/InyGa1-yAs interface was higher than that near another interface. For the first time, we explained the composition profile in this kind of superlattice based on the indium segregation theory. A new strain relaxation model, in which the 30-degree and 90-degree shockley partial dislocations were taken into account under both tensile and compressive strains, was presented to explain the difference of the smoothness between the GaAs/InyGa1−yAs interface and the InyGa 1−yAs/GaAs interface.

1998 ◽  
Vol 540 ◽  
Author(s):  
J.M. Glaskol ◽  
R. G. Elliman ◽  
J. Zou ◽  
D.J.H. Cockayne ◽  
J. D. Fitz Gerald

AbstractThe strain in GeSi/Si strained layer heterostructures is studied as a function of ion-irradiation and thermal annealing conditions and correlated with the defect microstructure in the GeSi alloy layer. For room temperature irradiation, compressive strain within the alloy layer increases with increasing ion fluence for both low (projected range of ions within the alloy layer) and high energy (projected range of the ions greater than alloy thickness) irradiation. In contrast, elevated temperature irradiation results in an increase in strain for low-energy irradiation, but a decrease for high-energy irradiation. For example, strain relaxation is observed in layers irradiated with I MeV 28Si+ at 253 °C. During subsequent annealing to 750 °C, the strain is partially recovered but relaxes again at temperatures > 750°C. This behavior is shown to be consistent with the evolution of intrinsic (vacancy-type) defects within the alloy layer.


2019 ◽  
Vol 20 (11) ◽  
pp. 1046-1051 ◽  
Author(s):  
Przemysław Gajda-Morszewski ◽  
Klaudyna Śpiewak-Wojtyła ◽  
Maria Oszajca ◽  
Małgorzata Brindell

Lactoferrin was isolated and purified for the first time over 50-years ago. Since then, extensive studies on the structure and function of this protein have been performed and the research is still being continued. In this mini-review we focus on presenting recent scientific efforts towards the elucidation of the role and therapeutic potential of lactoferrin saturated with iron(III) or manganese(III) ions. The difference in biological activity of metal-saturated lactoferrin vs. the unmetalated one is emphasized. The strategies for oral delivery of lactoferrin, are also reviewed, with particular attention to the metalated protein.


Author(s):  
Adi Ophir ◽  
Ishay Rosen-Zvi

This chapter traces the developments of various terms denoting “others” in biblical literature. In much of the biblical corpus, Israel is still one goy among many, and the difference between it and its Others is neither binary nor stable. After a brief analysis of the dynamics of familial and ethnwic separations in Genesis and Exodus, this chapter concentrates on the priestly and Deuteronomistic modes of separating peoples, examines the novelty and limitedness of the Deuteronomistic legislation, where the nokhri (stranger) is systematically contrasted for the first time with the Israelite (referred to as “your brother”), and follows the various modes of separations and their rationales.


Micromachines ◽  
2021 ◽  
Vol 12 (4) ◽  
pp. 399
Author(s):  
Sang-Jo Kim ◽  
Semi Oh ◽  
Kwang-Jae Lee ◽  
Sohyeon Kim ◽  
Kyoung-Kook Kim

We demonstrate the highly efficient, GaN-based, multiple-quantum-well light-emitting diodes (LEDs) grown on Si (111) substrates embedded with the AlN buffer layer using NH3 growth interruption. Analysis of the materials by the X-ray diffraction omega scan and transmission electron microscopy revealed a remarkable improvement in the crystalline quality of the GaN layer with the AlN buffer layer using NH3 growth interruption. This improvement originated from the decreased dislocation densities and coalescence-related defects of the GaN layer that arose from the increased Al migration time. The photoluminescence peak positions and Raman spectra indicate that the internal tensile strain of the GaN layer is effectively relaxed without generating cracks. The LEDs embedded with an AlN buffer layer using NH3 growth interruption at 300 mA exhibited 40.9% higher light output power than that of the reference LED embedded with the AlN buffer layer without NH3 growth interruption. These high performances are attributed to an increased radiative recombination rate owing to the low defect density and strain relaxation in the GaN epilayer.


1982 ◽  
Vol 72 (4) ◽  
pp. 709-716 ◽  
Author(s):  
Tan Keng-Hong ◽  
Lee Soo-Lam

AbstractDacus dorsalis Hend. infested eleven, D. cucurbitae Coq. five and D. umbrosus F. two of the eighteen common fruits and vegetables grown in Penang, West Malaysia. D. tau (Wlk.) infested bacang (Mangifera foetida), D. caudatus F. chilli (Capsicum annuum) and D. frauenfeldi Schin. water guava (Eugenia javanica), together with D. dorsalis. Pomelo (Citrus grandis) was found infested for the first time by D. cucurbitae. No flies were trapped using Capilure and trimedlure as baits. Cue-lure attracted D. caudatus, D. cucurbitae, D. frauenfeldi, D. occipitalis (Bez.) and D. tau. Methyl eugenol attracted D. dorsalis and D. umbrosus. Dorsalure was less attractive to D. caudatus and D. dorsalis than cue-lure and methyl eugenol, respectively, but it was equally attractive to D. frauenfeldi as cue-lure. Using traps baited with cue-lure or methyl eugenol in five ecosystems, the highest numbers of males of D. dorsalis, D. umbrosus, D. frauenfeldi and D. caudatus trapped were from a village, on a vegetable farm for D. cucurbitae, and D. occipitalis was only caught in a forest. Analysis showed that for each species of Dacus the difference between ecosystems was highly significant. The few examples caught in grassland were probably migrants.


2004 ◽  
Vol 19 (12) ◽  
pp. 3607-3613 ◽  
Author(s):  
H. Iikawa ◽  
M. Nakao ◽  
K. Izumi

Separation by implemented oxygen (SIMOX)(111) substrates have been formed by oxygen-ion (16O+) implantation into Si(111), showing that a so-called “dose-window” at 16O+-implantation into Si differs from Si(100) to Si(111). In SIMOX(100), an oxygen dose of 4 × 1017/cm2 into Si(100) is widely recognized as the dose-window when the acceleration energy is 180 keV. For the first time, our work shows that an oxygen dose of 5 × 1017/cm2 into Si(111) is the dose-window for the formation of SIMOX(111) substrates when the acceleration energy is 180 keV. The difference between dose-windows is caused by anisotropy of the crystal orientation during growth of the faceted buried SiO2. We also numerically analyzed the data at different oxidation velocities for each facet of the polyhedral SiO2 islands. Numerical analysis results show good agreement with the experimental data.


2001 ◽  
Vol 15 (17n19) ◽  
pp. 683-687
Author(s):  
A. SILVA-CASTILLO ◽  
F. PEREZ-RODRIGUEZ

We have applied the 45° reflectometry for the first time to study exciton-polaritons in quantum wells. The 45° reflectometry is a new polarization-modulation technique, which is based on the measurement of the difference [Formula: see text] between the p-polarization reflectivity (Rp) and the squared s-polarization reflectivity [Formula: see text] at an angle of incidence of 45°. We show that [Formula: see text] spectra may provide qualitatively new information on the exciton-polariton modes in a quantum well. These optical spectra turn out to be very sensitive to the zeros of the dielectric function along the quantum-well growth direction and, therefore, allow to identify the resonances associated with the Z exciton-polariton mode. We demonstrate that 45° reflectometry could be a powerful tool for studying Z exciton-polariton modes in near-surface quantum wells, which are difficult to observe in simple spectra of reflectivity Rp


2018 ◽  
Vol 2018 ◽  
pp. 1-6 ◽  
Author(s):  
Wei Xu ◽  
Yu-Lin Chen ◽  
Ying Zhao ◽  
Li-Jie Wang ◽  
Jiu-Jun Li ◽  
...  

Carbamazepine is known to produce the side effect of euphoria. As such, it lends itself to being a drug of abuse, particularly in the adolescent population. This retrospective study evaluated carbamazepine abuse, treatment course, and associated morbidity in Chinese adolescents. The median dose of carbamazepine resulting in overdose was 2,000 mg (800–5,000). Patients were largely from urban-rural fringe areas (76.47%, 52.94%) with school performance within the last 1/3 range and (52.94%) unsupervised by parents. 35.29% experienced an obvious sense of euphoria. All patients had nervous system symptoms, 6 (35.29%) cases developed coma (GCS < 8), and 5 (29.41%) cases experienced convulsion. Four cases were treated with hemodialysis. The incidence rate in young patients with repeat carbamazepine use and without the supervision of parents was higher than that in first-time users (5/7 versus 4/10), but the difference was not significant. The toxic dose of repeat users was 3428 ± 1035 mg, significantly higher than that of 1470 ± 646 mg in first-time users (P=0.001). Carbamazepine can produce a sense of euphoria, which is more likely to lead to its abuse and overdose in adolescents. To prevent carbamazepine abuse and overdose will be critical in educating at-risk adolescents and preventing associated morbidities in the future.


Cancers ◽  
2021 ◽  
Vol 13 (10) ◽  
pp. 2440
Author(s):  
Francesco Spagnolo ◽  
Bruna Dalmasso ◽  
Enrica Tanda ◽  
Miriam Potrony ◽  
Susana Puig ◽  
...  

Inherited pathogenic variants (PVs) in the CDKN2A tumor suppressor gene are among the strongest risk factors for cutaneous melanoma. Dysregulation of the p16/RB1 pathway may intrinsically limit the activity of MAPK-directed therapy due to the interplay between the two pathways. In our study, we assessed, for the first time, whether patients with germline CDKN2A PVs achieve suboptimal results with BRAF inhibitors (BRAFi)+/−MEK inhibitors (MEKi). We compared the response rate of nineteen CDKN2A PVs carriers who received first-line treatment with BRAFi+/−MEKi with an expected rate derived from phase III trials and “real-world” studies. We observed partial response in 16/19 patients (84%), and no complete responses. The overall response rate was higher than that expected from phase III trials (66%), although not statistically significant (p-value = 0.143; 95% CI = 0.60–0.97); the difference was statistically significant (p-value = 0.019; 95% CI = 0.62–0.97) in the comparison with real-world studies (57%). The clinical activity of BRAFi+/−MEKi in patients with germline CDKN2A PV was not inferior to that of clinical trials and real-world studies, which is of primary importance for clinical management and genetic counseling of this subgroup of patients.


2021 ◽  
Vol 1 (2) ◽  
pp. 041-048
Author(s):  
Benson Chinweuba Udeh

This study is on the production of quicklime from Ashaka limestone through calcination process. Effects of temperature, particle size and time on quicklime yield were determined. The experiment was carried out at temperatures of 800, 900, 1000, 1100 and 1200 0C, particle sizes of 80mm, 90mm, 100mm, 300mm and 425mm and times of 0.5hr, 1hr, 2hrs, 3hrs and 4hrs. Analyses of the results showed that quicklime was successfully produced from Ashaka limestone through the calcination process. Quadratic model adequately described the relationship between quicklime yield and calcination factors of temperature, particle size and time. Recorded model F-value of 134.35 implies that the model is significant. The predicted R² of 0.9597 is in reasonable agreement with the adjusted R² of 0.9844; the difference is less than the critical value of 0.2. Optimum yield of 73.48% was obtained at optima operating conditions; temperature of 1000 0C, particle size of 90 µm and time of 3 hrs.


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