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A 60-year-old woman with a past medical history of asthma presented with fulminant myocarditis 9 days after testing positive for SARS-CoV-2 and 16 days after developing symptoms consistent with COVID-19. Her hospital course was complicated by the need for veno-arterial extracorporeal membrane oxygenation, ventricular arrhythmias, and pseudomonas bacteremia. She ultimately recovered and was discharged to home with normal left ventricular systolic function. Thereafter, she developed symptomatic ventricular tachycardia, for which she received an implantable cardioverter-defibrillator and antiarrhythmic drug therapy.

Purpose Cardiac radioablation using stereotactic body radiation therapy is gaining popularity as a noninvasive treatment for otherwise refractory ventricular arrhythmias. As radiation oncologists might be unaccustomed to the lexicon used by cardiologists to describe the location of arrhythmogenic foci, a preliminary guide to cardiac-specific anatomy and orientation is needed to foster effective communication between the radiation oncologist and cardiology team. Methods and Materials Electrocardiogram-gated and respiratory-gated computed tomography imaging was acquired per institutional protocol. Additional relevant imaging modalities are described. The American Heart Association 17-segment model is described in detail because this framework is used frequently by cardiologists to describe the location left ventricular abnormalities. Results A step-by-step guide is provided for properly rotating the heart from standard orthogonal views obtained during radiation simulation to the cardiac-specific orientation needed to appreciate the 17-segment model. Once the proper configuration is achieved, the location of each segment is defined in detail. Conclusions This atlas serves as an introduction to the relevant anatomy and principles, and it provides a suggested approach to help delineate cardiac radioablation targets using the established American Heart Association 17-segment model.

Myocardial deposition of transthyretin (ATTR) or immunoglobulin light chain (AL) underlies cardiac amyloidosis (CA), with distinct treatments for each requiring accurate diagnosis. Cardiovascular magnetic resonance (CMR) is a valuable diagnostic and prognostic tool for CA ([1][1]). We report a novel

Milk protein concentrate (MPC) powders are increasingly utilized in manufacturing of protein fortified beverages. Thermal stability of the protein dispersions is of significant importance in such applications. It is known that a decrease in pH can induce partial dissociation of casein micelles and modify the natural equilibrium of calcium and phosphate between the micelles and the serum phase. The presence of soluble casein may improve the rehydration properties of MPC powders, and may impact their thermal stability. The objective of this work was to investigate the effects of partial acidification of milk prior to ultrafiltration on the heat stability of reconstituted MPC dispersions. Milk protein concentrate powders were prepared from skim milk acidified to pH6.0 by addition of glucono-δ-lactone, and then concentrated using ultrafiltration (UF) and diafiltration (DF). The heat stability of the reconstituted MPC dispersions was studied, by determining heat coagulation time, particle size, turbidity, viscosity, soluble and colloidal calcium and phosphate, and non-sedimentable casein both before and after heating at 120°C. Reconstituted MPC powders made with partially acidified skim milk contained lower soluble calcium and phosphate and exhibited very poor thermal stability compared to MPC powders made with skim milk at its natural pH. The thermal stability of the acidified MPC dispersions was not only recovered by restoration of pH and the serum composition through dialysis against skim milk, but it was improved compared to control MPC dispersions. All dialyzed samples had comparable pH, protein content and calcium and phosphate concentration, but the structure of the casein micelles was altered, causing differences in the type of soluble aggregates. It was concluded that the integrity of the casein micelles and the amount of dissociated, non-sedimentable caseins play a major role in determining the thermal stability of the MPC dispersions.

The real-time composition and structure of the passive film formed on a high nitrogen face-centered-cubic phase (γN) layer at the characterized transient corrosion currents from the electrochemical noise analyses in the borate buffer solution with the pH = 7.7 are investigated by the transmission electron microscope (TEM) with energy dispersion X-ray spectrum (EDS) using the focused ion beam (FIB) sampling. The thicker passive film of the γN phase layer on the nitrided AISI 304L in the borate buffer solutions is observed as two regions structure of O enriched n-type defect spinel γ-Fe2(N,O)3 and hydroxides in the outer region and Cr and N enriched p-type defect spinel (Fe,Cr)3(N,O)4 in the inner region, although few β-(Fe,Cr)OOH compounds are detected due to dehydration. The defect spinel in directions of , and is epitaxially growing on the γN phase matrix during the passivation up to 8 h with a decreasing lattice mismatch from 5.9 to 1%, which is attributed to lattice expansion of the γN phase and the defect spinel. The lattice expansion of the γN phase at the interface with growing passive film is affected by dissolving nitrogen outward to the borate buffer solution. The dissolving nitrogen in the defect spinel induces its lattice expansion by hydrolysis at the interface. The dense and low-defective passive films on the γN phase layer have a significant effect on the corrosion resistance due to inhibition of the absorption of aggressive ion and limitation of the carrier density.

The passive film thickening on a high nitrogen face-centered-cubic phase (γN) layer in a series of borate buffer solutions is in-situ characterized by the transient corrosion current and potential with the structure evolution in the photoelectrochemistry and electrochemical noise analyzes. The real-time nitrogen effect on the passivation is intended by controlling the proton concentration of the borate buffer solutions at the pH values of 6.5–8.9 with the immersion time up to 8 h. The γN phase layer on the nitrided AISI 304L austenitic stainless steel has a transitional maximum thickness with the firstly immersion time, and then gradually achieves a steady thickness value. Seven components, such as α-Fe2O3, FeO, Cr(OH)3, γ-FeOOH, CrOOH, Cr2O3 and γ-Fe2O3, are observed with 8 h, although no CrNx and FeNx compounds are detected due to lack of references in photoelectrochemistry. The nitrogen dissolving from the γN phase layer in the borate buffer solutions is clarified, according to the real-time photocurrent and transient corrosion current at the controllable pH values. The passivation transition period dependent on the nitrogen dissolving in the borate buffer solutions is proposed by the point defect model. The nitrogen hydrolysis to ammonia with a fast reaction rate is determined by the nitrogen concentration on the surface of the γN phase layer. The ammonia is further hydrolyzed to ammonium with a lower reaction rate which is mainly affected by proton concentration in the solutions. Therefore, the two-step nitrogen hydrolysis from the γN phase layer is in-situ discovered as an effect mechanism in the borate buffer solutions.

The earned income tax credit (EITC) is the largest U.S. poverty alleviation program for families with children, and state EITC policies provide a modest supplement to the federal program. Yet there are few studies of the effects of state EITC policies on population health. We examined whether state EITC policies affect mental health and health behaviors. Participants were drawn from the 1995-2015 waves of the Panel Study of Income Dynamics, a diverse national cohort study (N=10,567). We used a quasi-experimental difference-in-differences analysis to examine the effects of state EITC programs among eligible individuals, accounting for secular trends among similar individuals in non-EITC states. Outcomes included self-reported general health, psychological distress, alcohol use, and smoking. The mean size of state EITC refunds in our sample was $265 for eligible individuals. In the overall sample, state EITC programs were not associated with any health outcomes of interest. This finding was robust to alternative specifications, and similar in subgroup analyses by gender and marital status. This study suggests that state EITC programs, which tend to provide smaller refunds than the federal program, may not be large enough to have a positive impact on mental health and health behaviors. These findings may inform policymaking related to the generosity of state EITC programs, especially as states seek to address the socioeconomic consequences of the COVID-19 pandemic.

Deep oscillation magnetron sputtering (DOMS) is a novel high power impulse magnetron sputtering technique, which offers large voltage oscillation packets to generate a stable high-power discharge plasma with high ionization under virtually arc-free conditions. CrN/TiN superlattice coatings with various modulated periods (Λ) were deposited by the combined DOMS and pulsed dc magnetron sputtering. CrN/TiN superlattice coatings with the Cr/(Cr + Ti) ratio ranging from 0.177 to 0.496 exhibited a single phase face-centered cubic structure with a strong (111) texture. As the Λ was increased from 5.7 to 10.2 nm, the residual stress was increased from − 2.1 to − 5.6 GPa. The increase in Λ led to an initial increase, followed by a decrease in hardness, and the H/E* and H3/E*2 ratios. The coating at Λ = 6.3 nm showed the highest adhesion with the highest HF level in Rockwell C tests and critical loads in scratch tests due to the highest hardness of 36 GPa, H/E* ratio of 0.093 and H3/E*2 ratio of 0.316. The predominant adhesive failure mode in scratch tests was buckling failure independent of the changes of Λ and substrate hardness. However, the increase in substrate hardness resulted in an increase in critical loads (LC1, LC2, LC3 and LC4), especially for a significant increase in LC3, due to the increased cooperative deformation of a coating/substrate system by increasing toughness of coatings, cohesion/adhesion and substrate hardness. The increased adhesion was responsible for the increased pitting and stress corrosion cracking resistance in 3.5 wt.% NaCl aqueous solution due to the optimized Cr/(Cr + Ti) ratio and Λ.

SummaryThe yeast homologs of the ATM and ATR DNA damage response kinases play key roles in telomerase-mediated telomere maintenance, but the role of ATM/ATR in the mammalian telomerase pathway has been less clear. Here, we demonstrate the requirement for ATM and ATR in the localization of telomerase to telomeres and telomere elongation in immortal human cells. Stalled replication forks increased telomerase recruitment in an ATR-dependent manner. Furthermore, increased telomerase recruitment was observed upon phosphorylation of the shelterin component TRF1 at an ATM/ATR target site (S367). This phosphorylation leads to loss of TRF1 from telomeres and may therefore increase replication fork stalling. ATM and ATR depletion reduced assembly of the telomerase complex, and ATM was required for telomere elongation in cells expressing POT1ΔOB, an allele of POT1 that disrupts telomere-length homeostasis. These data establish that human telomerase recruitment and telomere elongation are modulated by DNA-damage-transducing kinases.

Deep oscillation magnetron sputtering (DOMS) is a novel high power impulse magnetron sputtering technique, which offers large voltage oscillation packets to generate a stable high-power discharge plasma with high ionization under virtually arc-free conditions. CrN/TiN superlattice coatings were deposited using a combined DOMS and pulsed dc magnetron sputtering (PDCMS) in a closed field unbalanced magnetron sputtering configuration. The Cr target was powered at 400 W by DOMS and Ti target was powered at 2000 W by PDCMS. The negative substrate bias ( V s ) ranged from 0 V to −100 V. As the V s was increased, CrN/TiN superlattice coatings showed a single phase face-centered cubic structure with a strong (1 1 1) texture. Correspondingly, the coatings exhibited the dense microstructure with well-defined interfaces between CrN and TiN layers. The increase in V s led to a decrease in grain size and an increase in the compressive residual stress. The hardness and Young's modulus of the coatings increased with increasing V s . The H / E * and H 3 / E * 2 ratios and critical loads L C in scratch test showed an initial increase, followed by a decrease. The wear mechanism changed from severe adhesion wear to abrasion wear. The coating deposited at V s = −60 V exhibited mild abrasion wear with the lowest friction coefficient of 0.27 and the lowest specific wear rate of 0.5 × 10 −6 mm 3 N −1 m −1 due to high hardness, H / E * and H 3 / E * 2 ratios, L C1 and L C3 of 36 GPa, 0.094, 0.316, 15.3 N and 24 N, respectively. The coatings also exhibited increasing pitting corrosion resistance with lower current density and higher corrosion potential in 3.5 wt% NaCl aqueous solution. Combined DOMS + PDCMS techniques can provide the engineering surfaces for the industrial applications with the combined improvement in wear and corrosion resistance.

Background Hypertension is common among patients who have undergone liver transplantation and is a major contributor to cardiovascular events. Few studies have studied the risk factors associated with post–liver transplantation (LT) hypertension. This prospective study assessed the prevalence of post-LT hypertension and associated preoperative risk factors. Methods From May 2008 to December 2009, 79 normotensive adult patients (≥18 years old) who underwent living-donor LT with a median follow up of 4.79 ± 0.88 years were enrolled. Patients' pre-LT demographics, clinical data, pre-LT diabetes, and immunosuppressive agents used after LT were studied for their association with post-LT hypertension. Results The prevalence of post-LT hypertension was 49.4%. The independent risk factors for post–living-donor LT hypertension were pre-LT systolic blood pressure (SBP; odds ratio [OR], 1.04; 95% confidence interval [CI], 1.00–1.09; P = .039) and post-LT administration of mammalian target of rapamycin (mTOR) inhibitors (OR, 4.08; 95% CI, 1.40–11.94; P = .010). Pre-LT diabetes had a negative predictive value (OR, 0.15; 95% CI, 0.03–0.74; P = .019). Neither age, male sex, smoking, pre-LT serum cholesterol and triglyceride levels, tacrolimus, nor glucocorticoid was associated with post-LT hypertension. Conclusions The prevalence of hypertension is high after LT. Higher pre-LT SBP and post-LT mTOR inhibitor administration predispose patients to post-LT hypertension.

New studies show that POMC neurons linked to appetite suppression also play a key role in stress hormone responses., Mammals exhibit instinctive reactions to danger critical to survival, including surges in blood stress hormones. Hypothalamic corticotropin-releasing hormone neurons (CRHNs) control stress hormones but how diverse stressors converge on CRHNs is poorly understood. We used sRNA profiling to define CRHN receptors for neurotransmitters and neuromodulators and then viral tracing to localize subsets of upstream neurons expressing cognate receptor ligands. Unexpectedly, one subset comprised POMC (proopiomelanocortin)–expressing neurons in the arcuate nucleus, which are linked to appetite suppression. The POMC neurons were activated by one psychological stressor, physical restraint, but not another, a predator odor. Chemogenetic activation of POMC neurons induced a stress hormone response, mimicking a stressor. Moreover, their silencing markedly reduced the stress hormone response to physical restraint, but not predator odor. These findings indicate that POMC neurons involved in appetite suppression also play a major role in the stress hormone response to a specific type of psychological stressor.

SUMMARY An experiment was conducted to assess the effects of a novel thermostable phytase in male broiler chicks (Ross 308) fed available P (AP)-deficient diets on growth performance and bone mineralization. The treatments consisted of 8 experimental diets: 1 positive control diet containing an adequate level of AP, 1 negative control diet deficient in AP, and 6 diets with the same level of AP as in the negative control but supplemented with different levels of phytase (250, 500, 750, 1,000, 1,250, and 1,500 phytase units/kg of diet). The addition of phytase significantly improved (P 0.05) were found in FCR and bone mineralization among the broilers fed different levels of phytase and those fed the positive control diet. In conclusion, normal growth performance and bone mineralization were maintained in broilers fed AP-deficient diets supplemented with thermostable phytase.

Particle size distributions of nano- and ultrasonic mists, were measured under storage environments with high humidity. Mists generated using nanomist humidifiers have average particle diameters

An arch under an in-plane central concentrated radial load is subjected to combined axial compressive and bending actions. When these combined axial compressive and bending actions reach a certain value, the arch may suddenly deflect laterally and twist out of its plane of loading and fail in a lateral–torsional buckling mode. This paper derives analytical solutions for the elastic lateral–torsional buckling load of pin-ended circular arches that are subjected to a central concentrated load, using the principle of stationary potential energy in conjunction with the Rayleigh–Ritz method. Analytical solutions of the buckling load for in-plane fixed and out-of-plane pin-ended arches and for the case of the load acting above or below the shear centre are also derived. The analytical solutions are compared with results of a commercial finite element package ANSYS and a finite element code developed by authors elsewhere for arches with different slendernesses, included angles, and cross-sections. The agreement between the analytical solutions and the finite element results is very good.

Low-frequency damping capacities of dual-phase Mg– x Li–0.5Zn alloys with x = 6.0 (α-rich LZ60), 9.5 (LZ100) and 10.5 (β-rich LZ110) are studied by dynamic mechanical analyzer. Both LZ100 and LZ110 have a significant P 1 peak but only LZ110 exhibits a significant P 2 peak. LZ60 does not show any obvious internal friction peak and has the lowest tan δ value of high-temperature damping background (HTDB). Both P 1 peak and HTDB of LZ100 are frequency dependent and thermal activated with their activation energy being 0.87 and 0.59 eV, respectively. The relatively low activation energy of HTDB for LZ100 is corresponding to the smaller atomic radius of Li atoms in Mg alloys which facilitates the dislocation climbing process at moderately high temperature. The strain amplitude dependence of tan δ value shows that, for LZ100 at room temperature, the critical strain is 3 × 10 −5 .

Our aim was to investigate how two conditions of whey processing, pH and heat treatment, affect the physical properties of stirred yoghurts fortified to 45 g protein kg−1 with whey protein concentrates (WPC). Cheddar whey was heated at pH 6.4 or pH 5.8 at 72 °C for 15 s, eventually heated further at 82 or 88 °C for 78 s, ultrafiltered, and spray dried. Resulting WPC contained 38% protein; the denaturation level of the whey protein was 10–53%. There were significant ( P 0.05 ) differences in physical properties of WPC fortified yoghurts: water-holding capacity ranged from 33% to 46% and elastic modulus ranged from 63 to 145 Pa depending on whey processing. WPC with low denaturation level produced yoghurts with high elastic modulus and water-holding capacity. Minimizing the heat treatment during whey processing maximized the functional properties of WPC to be used in yoghurt.

Yeast has proven to be a powerful system for investigation of chromatin structure. However, the extent to which yeast chromatin can serve as a model for mammalian chromatin is limited by the significant number of differences that have been reported. To further investigate the structural relationship between the two chromatins, we have performed a DNA topological analysis of pRSSVO, a 5889 base-pair plasmid that can replicate in either yeast or mammalian cells. When grown in mammalian cells, pRSSVO contains an average of 33 negative supercoils, consistent with one nucleosome per 181 bp. This is close to the measured nucleosome repeat length of 190 bp. However, when grown in yeast cells, pRSSVO contains an average of only 23 negative supercoils, which is indicative of only one nucleosome per 256 bp. This is dramatically different from the measured nucleosome repeat length of 165 bp. To account for these observations, we suggest that yeast chromatin is composed of relatively short ordered arrays of nucleosomes with a repeat of 165 bp, separated by substantial gaps, possibly corresponding to regulatory regions.

The recent innovations in metallic glasses have led to new alloy classes that may be vitrified and a re-examination of the commonly used criteria for glass formation and stability. In one case large, bulk volumes may be slowly cooled to the glassy state that signifies a nucleation-controlled synthesis. The other important case is represented by Al and Fe based marginal glass formers that have been synthesized under growth controlled kinetic conditions mainly by rapid solidification processes. With marginal glass forming alloys the termination of the amorphous state upon heating is often characterized by a primary crystallization reaction that yields a high number density in the range of 1021–1022 m−3 of Al nanocrystals (15–20 nm in diameter) dispersed within a residual amorphous matrix. At the same time the results from alternate synthesis strategies involving intense cold rolling reveal that the primary crystallization reaction can be bypassed during deformation alloying of elemental multilayers or enhanced during deformation bonding of amorphous ribbons. The kinetics analysis of the crystallization behavior provides insight into the origin of the dispersed nanocrystal and amorphous matrix microstructures, the important influence of heterogeneous catalysts and an effective assessment of the overall stability that are essential for microstructure control.

The clinico-pathological features of 17 patients displaying a myopathy with lobulated (trabeculated) fibers are reported. All these patients had a limb girdle phenotype and at least 20% of lobulated fibers in their muscle biopsies. There were ten females and seven males. The onset of symptoms ranged from 2 to 55 years (mean 24). The average age at the time of muscle biopsy was 39 (range 3-63). Interestingly, in six patients, high prevalence of lobulated fibers was observed at the second biopsy only, performed on average 11 years after the first or in another muscle. Six patients had a suggestively positive family history. Facial weakness was noted in two patients (genetic study confirmed FSH dystrophy). The course and the severity of weakness varied from one patient to another. Immunohistochemistry and Western blot analyses revealed one Duchenne carrier, one alpha-sarcoglycanopathy, no dysferlinopathy and four calpain deficiencies (including one patient with FSH dystrophy), but SSCP revealed mutation in the calpain gene in only one of the patients. These results show that (1) myopathies with lobulated fibers are clinically and genetically heterogeneous, (2) lack of calpain expression by Western blot analysis is not always associated with null mutation, (3) a molecular diagnosis is made in less than 40% of myopathy with lobulated fibers, (4) when observed, lobulated fibers are most prominent in proximal muscles and require time to appear.

Background: The use of the Fick principle and the thermodilution (TD) method via right heart catheterization (RHC) has remained the most reliable means of cardiac output (CO) measurement. Using CMR, phase velocity mapping (PVM) is a non-invasive, rapid, highly reproducible technique to measure CO.

It has truly been an honor to serve as president of ADSA this past year. It was a real pleasure to have worked alongside so many smart, hard-working, and caring ADSA members who generously volunteered their time to serve on the ADSA Board of Directors and ADSA committees, and work on various other activities. Additionally, ADSA and FASS staff provided the continuity and professional service to support, facilitate, and guide us all year. Hence, I am happy to report on some of the highlights of our past year. Overall, some new initiatives were undertaken that will strengthen ADSA’s future and we made some noteworthy accomplishments that continue to reinforce ADSA’s vision as the society for science, education, and service to the dairy industry.

Broad-area, electrical injection, interband mid-infrared lasers emitting between 3.2 and 4.7 μm have been grown by low-pressure metal organic chemical vapor deposition. A InAsSbP based double heterostructure laser emitting at 3.2 μm is reported to produce 450 mW in continuous mode operation. Furthermore, the InAsSb and InAsP alloys have been used for the growth of strained-layer superlattice lasers emitting above 4.0 μm. These lasers demonstrate threshold current densities as low as 100 A cm −2 and output powers up to 546 mW.

Analytical expressions are obtained for the temporal evolution of the perimeter fraction during a phase transformation for both site-saturated nucleation and nucleation at a constant rate. In the former case, these expressions are then validated by a direct comparison with the results of two-dimensional computer simulations of nucleation and growth to impingement. Finally, the role of the evolving perimeter fraction on the energetics of transforming systems is discussed.

Ge ions were implanted into SiO 2 films thermally grown on crystalline Si at an energy of 60 KeV and with a dose of 1 × 10 16 cm −2 , followed by annealing at different temperatures. Under an excitation of the 514.5 nm line of an Ar + laser, the implanted films exhibit a broad infrared photoluminescence (PL) at room temperature. The PL peak displays a redshift with increasing annealing temperature. The experimental results from Raman scattering, Rutherford backscattering and X-ray photoelectron spectroscopy were utilized to analysis the structure of the films. The PL mechanism is discussed in the light of the results of structural analyses.

Various computational schemes for the determination of nucleation conditions from fully coalesced product microstructures are examined. In particular, a variety of types of nucleation sites, including those on the edges and corners of an underlying structure, are considered. The analysis is facilitated by simulating idealized cases wherein the nucleation conditions are known. In cases where only one type of site is active, the spatial distribution of nucleation sites is quantified in terms of neighbor distributions and correlation functions. In cases of multiple types of site potency, maps revealing important microstructural behavior and trends are constructed. It is found that the dimensionality of the subspace of sites on which nucleation occurs can be described and thereby the unique signatures of bulk, edge and corner nucleation in the calculated quantities can be identified. The results of the simulations allow possible nucleation conditions to be identified which give rise to a given experimental microstructure.

Photoluminescence (PL) properties of alternating hydrogenated nanocrystalline silicon/amorphous silicon multilayers were investigated at room temperature and low temperature (77 K). The room-temperature PL spectra clearly show two peaks at about 1.54 and 1.7 eV. The ∼1.7 eV peak has no crystallite size dependence of the peak energy. The low-temperature PL spectra can be decomposed into three bands peaked at 1.53, 1.58 and 1.65 eV. The 1.53 eV band is related to the growth process of our samples. The 1.58 eV band is believed to be related to a -Si : H tissue. For the 1.65 eV band, spectral analysis indicates that the radiative recombination of photogenerated carriers in the near-surface region of nanocrystallites is responsible for the visible PL band.

The temperature dependence of visible range photoluminescence (PL) properties of nanocrystallites embedded in silicon films deposited at the substrate temperature T s = 50–150°C by PECVD method was studied. It was found that there are many differences between them and that of the near-infrared range PL in ordinary a -Si : H films. Combining with the results of photo-absorption studies of these nanocrystalline samples, we discussed the mechanism of their visible range PL. We suggest that the light excitation occurs in both the nanocrystallites core and their surface regions; however, the radiative recombination can only occur between the electrons and holes in the localized band tail states of the crystallite surface regions, which are more disordered than ordinary a -Si : H with their defect states extending more deeply into the band gap.

Raman spectra of hydrogenated nanocrystalline silicon films clearly exhibit two size- and crystalline-fraction-dependent spectral regions related to the structural properties of nanocrystals. One is the crystalline band from crystallite core consisting of two neighbouring peaks at 513 and 519 cm−1. The appearance of the two peaks is attributed to the contribution of both LO and TO phonons at phonon wavevector q ≠ 0 due to phonon confinement. The other consists of several small peaks superposed on the broad band at ∼480 cm−1. Based on a three-region model of the nanocrystallites, the existence of these small peaks is proposed to be due to atomic vibrations of the near-surface regions in silicon nanocrystallites, sandwiched between the crystalline core and disordered outer surface.

An intense ultraviolet photoluminescence peaked at 286 nm and 396 nm from Ge + -implanted SiO 2 film thermally grown on crystal silicon was observed. After 1100°C annealing, a weak near-infrared emission peak at 840 nm was measured at low temperature (77 K). Annealing analyses and X-ray photoemission spectroscopy measurement show that the ultraviolet peaks are caused by S 1 → S 0 and T 1 → S 0 transition in GeO color centers formed during implantation and annealing, while the infrared one is due to the quantum confinement effect in Ge clusters formed at high annealing temperatures.

We examine quantitatively the impact of heterogenous nucleation on the temporal evolution of a phase transformation with particular emphasis on the correlation of nucleation site distribution and product phase microstructure. This is accomplished by investigating the spatial correlations in the transforming system via the calculation of several non-equilibrium,n-point correlation functions and thereby defining associated transformation fractions and correlation lengths. Computer simulations of transformations are also employed in order to validate the theoretical description and to relate the microstructural features of the evolving phase to relevant length and time scales in the problem. Finally, our findings are related to the results of experimental calorimetric studies of phase formation in thin films.

Raman spectra of C 60 molecules embedded in porous silicon (PS) through both physical deposition and chemical coupling were examined in the wavenumber ranges 400–550 and 1400–1500 cm −1 . Some new vibrational modes relevant to C 60 molecular environments and disorder effects inside solid C 60 were obtained with large intensities. Particularly, a downshift of the pinch A g mode which is sensitive to charge on the C 60 was observed of more than 12 cm −1 , indicating a charge transfer of at least 2 electrons per C 60 molecule in our samples. The experimental result is consistent with our previous analysis that the enhanced photoluminescence of the C 60 molecules embedded in PS arises from the radiative recombination of carriers which form in PS and then transfer to C 60 molecules.

Ripening inhibited ( rin ) tomato plants were grown in silicate sand and watered with half-strength Hoagland's solution until flowering. After flowering, plants were watered until run-off daily with full-strength Hoagland's solution containing 5 mM (control) or 1 mM calcium, or full-strength Hoagland's solution with 1.25 mM or 2.5 mM Na 2 EDTA. Fruit pericarp calcium levels were the same in Na 2 EDTA and control treatments at 90 days postpollination. The 1 mM Ca treatment significantly decreased total pericarp Ca levels compared to the control treatment. Sodium levels were higher in fruit from Na 2 EDTA-treated plants than controls. Fruit from control and 1 mM Ca treatments had significantly higher Zn than fruit from the Na 2 EDTA-treatments. None of the treatments induced increased ethylene production, redness, or increased soluble solids content of rin fruit.

The osteoclast is a cell type that is highly specialized for its bone resorption function. In order to decipher the numerous biochemical functions of osteoclasts, a description of the gene expression profile of osteoclasts would be beneficial. We have sought to identify genes that are highly expressed in osteoclasts by partially sequencing 194 randomly chosen cDNA clones from a representative rabbit osteoclast cDNA library. Comparison to nucleic acid and protein sequence databases indicates that 135 of these cDNAs are identical to or homologous to known mammalian genes. Reverse transcription-polymerase chain reaction (RT-PCR) assays with micro-isolated osteoclasts were used to verify the osteoclast expression of some of these genes. Fifty-nine cDNAs, including two abundantly expressed species, have no significant similarity to the sequence databases and likely represent novel genes. The most abundant of the osteoclast expressed genes encode cofilin and the vacuolar H + -ATPase 16 kd subunit. Each were represented at a frequency of 4.1 % of the clones in the library (95% confidence interval = 2.4–6.6%). The high expression of these gene products is consistent with the high motility of osteoclasts and their very active hydrogen ion secretion. Other abundantly expressed sequences include (3-actin (95% C.I. = 2.0–6.0%), creatine kinase B (95% C.I. = 1.2–4.9%), c- fms and ribosomal protein L18 (95% C.I. = 0.8–4.3%), and cathepsin-OC2, cyclophilin, δ-aminolevulinate synthetase, 165 mitochondrial rRNA, and two novel gene sequences (95% C.I. = 0.5–3.6%).

We have investigated the nature of the compensation phenomena that limit carrier activation in GaAs implanted with 1 MeV Si ions to a dose of 3 × 1015ions/cm2, and subsequently annealed at 900°C for 10 s. The depth profiles of the Si implants and the net carrier concentration, measured using secondary ion mass spectrometry and electrochemical capacitance-voltage profiling, respectively, reveal a large disparity in the region around the maximum of the Si distribution. Structural characterization, using ion channeling and transmission electron microscopy, reveals the formation of a buried band of interstitial dislocation loops in approximately the same region where the carrier concentration is highly compensated. However, previous works have shown that the remnant loops are not directly responsible for the deactivation of Si. The apparent paradox is resolved with the help of photoluminescence measurements as a function of depth performed on samples bevel-etched into a wedgelike shape. The photoluminescence experiments show that Si atoms sitting on As sites are mainly responsible for the compensation of the Si donors. Indeed self-compensation is to be expected due to the amphoteric nature of Si in GaAs. In addition, emissions corresponding to gallium-vacancy complexes, arsenic-vacancy complexes, as well as other implantation induced residual defects are observed. It is argued that a fraction of the vacancies and interstitials generated during the implantation collapse separately upon annealing giving rise to either vacancy-type defects or interstitial-type defects, respectively. The effect of these defects on the carrier concentration is discussed.

Electrical activation in Si-implanted and annealed GaAs/AlGaAs superlattices (SLs) has been studied as a function of implantation temperature and dose. Carrier concentration, measured by the electrochemical capacitance-voltage profiling, is shown to be strongly dependent on implantation temperature. When SLs are implanted at room temperature or lower, electrical activation is severely suppressed in the near-surface region, where the carrier concentration is one to two orders of magnitude lower than the maximum (1–3) × 1018/cm3 observed near the implant peak position. Similar deactivation behavior was observed in Si-implanted GaAs crystals, but the disparity between the minimum and maximum of the carrier concentration was significantly less than one order of magnitude. The minimum in carrier concentration profiles is explained in terms of carrier deactivation by the near-spherical voids of 25–200 A in diameter which are formed only in the near-surface regions, as revealed by transmission electron microscopy analysis. The larger carrier deactivation in the SL materials is attributed to the combined effects of electron confinement by the AlGaAs into the GaAs regions together with the preferential formation of voids in the GaAs layers.