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To identify high-valued coproducts from commercially processed corn germ, it was necessary to determine the effect of processing conditions on corn germ proteins. We found that significantly less protein was extracted from commercial wet-milled as compared to dry-milled corn germ using Tris, sodium dodecyl sulfate (SDS) buffer containing 14 mM 2-mercaptoethanol at 100 degrees C for 10 min. SDS-polyacrylamide gel electrophoresis (PAGE) revealed a number of proteins with molecular masses ranging from approximately 10 to 66 kDa for the dry-milled corn germ as compared to only a few significant protein bands centered around 23 kDa in the wet-milled corn germ. The protein content of the wet- and dry-milled corn germ was approximately the same; however, nonprotein nitrogen values were significantly greater for the wet-milled than for the dry-milled germ. The distribution of fractionated germ protein freshly excised from the embryo of yellow dent corn kernels was more similar to that of dry-milled than wet-milled corn. SDS-PAGE of laboratory preparations of wet-milled corn germ more closely resembled commercial dry- than wet-milled corn germ, which could be attributed to limited microbial growth during steeping in the laboratory preparations.

An important aspect of extraction using an organic solvent that is often ignored in many laboratory scale studies is thorough solvent recovery. Although most of the solvent can be recovered with a centrifuge, the solvent left on the ‘dry’ stream must be evaporated. A custom built pilot-scale settling tank was used to separate maize particles from ethanol extracts into water with little dilution of the extract liquid. The larger particles that settled in the first one-fourth of the tank were carried out by a continuous water flow 76 cm below the extract layer. The large particles had 80% higher protein mass fraction than the smaller particles that collected in the bottom of the settling tank downstream from the extract inlet. Water flow was confined to the bottom of the tank and extracted particles were prevented from accumulating in the settling tank with a much lower water/extract flow rate ratio than needed for a smaller settling tank. The mass ratio of entrained extract liquid/settled solids (0.5) was one-half that observed in previous methods using smaller tanks. This is caused by a more stable extract/water interface. The yield from finer, 1 mm meal, was slightly lower than 2 mm meal and increased extract liquid entrainment. Consequently, the 2 mm particle size is the minimum that should be used with this process.

A novel approach to pressureless sintering based on the combination of rapid-rate sintering, rate-controlled sintering, and two-step sintering under a controlled atmosphere is proposed. This combined sintering method facilitates control of grain and pore morphology. The application of this sintering approach for pure nanocrystalline barium titanate powder enables the suppression of grain growth during the intermediate and final stages of sintering and the production of fully dense ceramics with 108 nm grain size. The grain growth factor is 3.5, which is three and 17 times smaller than rate-controlled and conventional sintering, respectively.

Why is there an increased need for quantitative indicators of student socioeconomic status at the school level? What alternative approaches have been used to measure SES? Can principals accurately estimate the SES distribution of their student populations? How do their estimates correlate with other indexes o f family SES?

Background Using diffusion tensor imaging (DTI), we previously reported abnormalities in two critical white matter tracts in schizophrenia, the uncinate fasciculus (UF) and the cingulum bundle (CB), both related to fronto–temporal connectivity. Here, we investigate these two bundles in unmedicated subjects with schizotypal personality disorder (SPD). Methods Fifteen male SPD subjects and 15 male control subjects were scanned with line-scan DTI. Fractional anisotropy (FA) and mean diffusivity (Dm) were used to quantify water diffusion, and cross-sectional area was defined with a directional threshold method. Exploratory correlation analyses were evaluated with Spearman’s rho, followed by post hoc hierarchical regression analyses. Results We found bilaterally reduced FA in the UF of SPD subjects. For CB, there was no significant group difference for FA or Dm measures. Additionally, in SPD, reduced FA in the right UF was correlated with clinical symptoms, including ideas of reference, suspiciousness, restricted affect, and social anxiety. In contrast, left UF area was correlated with measures of cognitive function, including general intelligence, verbal and visual memory, and executive performance. Conclusions These findings in SPD suggest altered fronto–temporal connectivity through the UF, similar to findings in schizophrenia, and intact neocortical–limbic connectivity through the CB, in marked contrast with what has been reported in schizophrenia.

The leftward hemispheric dominance in language processing may be associated with fundamental functional asymmetry in the primary auditory cortex (PAC). Based on repeated functional MRI (fMRI) measurements, we investigated the presence of functional asymmetry in the human PAC using binaural presentation of linguistic sounds (two-syllable nouns) and simple tonal stimulation. Eight right-handed volunteers underwent nine fMRI sessions, approximately eight weeks apart, spanning the duration of more than a year. The PAC from each hemisphere was manually segmented and the volume of activation, detected within the segmented region-of-interest, was measured across the subjects and sessions to generate functional laterality indices. Although variations existed in activation volume between sessions and subjects, we found predominant and consistent leftward functional asymmetry in PAC during both linguistic and non-linguistic sound stimulations.

There have been extensive studies of germanium (Ge) grown on planar silicon (Si) substrates by the Stranski-Krastanow (S-K) mechanism. In this study, we present S-K growth of Ge on Si nanowires. The Si nanowires were grown at 500 degrees C by a vapor-liquid-solid (VLS) method, using silane (SiH4) as the gaseous precursor. By switching the gas source from SiH4 to germane (GeH4) during the growth and maintaining the growth conditions, epitaxial Ge islands deposited on the outer surface of the initially formed Si nanowires. Transmission electron microscopy (TEM), scanning TEM, and energy-dispersive X-ray spectroscopy techniques were utilized to identify the thin wetting layer and the three-dimensional Ge islands formed around the Si core nanowires. Cross-sectional TEM verified the surface faceting of the Si core nanowires as well as the Ge islands.

Removing solid particles from ethanolic corn extracts by gravitational settling into a water layer has been studied as part of a project to develop a low cost method to extract ethanol-soluble protein from corn meal. Settling has several advantages over industrially proven methods of liquid/particle separation: (1) less expensive equipment; (2) particles that settle at different rates can be collected from different outlets, and (3) extract liquid entrained by settling particles dissolves in the water from which the ethanol can be recovered by distillation. When fine particles were pumped as part of the extract into the 5-l settling layer at a high enough rate, they formed a particle layer at the extract/water interface. The particle layer prevents further settling and is a non-sustainable operating condition. The layer does not form when the mass fraction of particles in the extract was 0.11 or less. This value is greater than the value obtained by extrapolating published settling data for denser (mineral) particles. Overall, entrainment of extract liquid for the settling was about the same as entrainment during centrifugation. In-line measurements and recordings of ethanol concentration, density, and particle content of the water stream carrying settled coarse particles from the settling tank showed that specific entrainment was greater for the finer particles.

Boron-doped silicon (Si) nanowires, with nominal diameters of 80 nm, were grown via the vapor–liquid–solid (VLS) mechanism using gold (Au) as a catalyst and silane (SiH 4 ) and diborane (B 2 H 6 ) as precursors. The microstructure of the nanowires was studied by scanning electron microscopy, transmission electron microscopy and electron energy-loss spectroscopy. At lower B 2 H 6 partial pressure and thus lower doping levels (⩽1×10 18 cm −3 ), most of the boron-doped Si nanowires exhibited high crystallinity. At higher B 2 H 6 partial pressure (∼2×10 19 cm −3 doping level), the majority of the wires exhibited a core–shell structure with an amorphous Si shell (20–30 nm thick) surrounding a crystalline Si core. Au nanoparticles on the outer surface of the nanowires were also observed in structures grown with high B/Si gas ratios. The structural changes are believed to result from an increase in the rate of Si thin-film deposition on the outer surface of the nanowire at high B 2 H 6 partial pressure, which produces the amorphous coating and also causes an instability at the liquid/solid interface resulting in a loss of Au during nanowire growth.

The purpose of this study was to investigate abnormalities in the surface complexity of the prefrontal cortex and in the hemispheric asymmetry of cortical complexity in first-episode patients with schizophrenia.An estimate of the surface complexity of the prefrontal cortex was derived from the number of voxels along the boundary between gray matter and CSF. Magnetic resonance imaging scans were acquired from patients with a first episode of schizophrenia (N=17), patients with a first episode of affective psychosis (N=17), and normal comparison subjects (N=17), age-matched within a narrow age range (18-29 years). This study group was the focus of a previous study that showed lower prefrontal cortical volume in patients with schizophrenia.Prefrontal cortical complexity was not significantly different among the groups. However, the schizophrenia patients differed significantly from the normal comparison subjects in asymmetry, with the schizophrenia patients showing less left-greater-than-right asymmetry in cortical complexity than the comparison subjects.An abnormal pattern of asymmetry in the prefrontal cortex of first-episode patients with schizophrenia provides evidence for a neurodevelopmental mechanism in the etiology of schizophrenia.

The microchemical and microstructural origins of insulation-resistance degradation in BaTiO3-based capacitors are studied by complementary impedance spectroscopy and analytical transmission electron microscopy. The degradation under dc-field bias involves electromigration and accumulation of oxygen vacancies at interfaces. The nonstoichiometric BaTiO3−δ becomes locally more conducting through increased oxygen vacancy concentration and Ti ion reduction. The symmetry across the dielectric layer and locally across each grain is broken during the degradation process. Locally, the nonstoichiometry becomes so severe that metastable lattice structures are formed. The degradation in insulation resistance at the grain boundaries and electrode interfaces is associated with the double Schottky-barrier potential lowering and narrowing. This may correlate with an effective decrease in net acceptor charge density at the grain boundaries.

Impedance spectroscopy, transmission electron microscopy, and electron energy-loss spectroscopy are used to correlate local electrical properties with the microstructure and microchemistry of BaTiO3 in Ni-electrode multilayer ceramic capacitors. High densities of linear defects and some grains with structural modulations are observed in BaTiO3 grains in the as-cofired capacitors. The modulated structure is formed on {111} planes of the BaTiO3. Both types of structural defects are associated with high concentrations of oxygen vacancies. In particular, the oxygen content in the BaTiO3 grains that are in direct contact with the internal Ni electrodes is less uniform with a systematic decrease in oxygen content towards the electrode. In the capacitors that are reoxidized in a higher oxygen partial pressure at lower temperature, the BaTiO3 grains are almost free of linear defects and structural modulations and the oxygen content is homogeneous throughout the BaTiO3 active layers. A concomitant improvement in t...

LaB6-ZrB2 eutectics were directionally solidified by a zone melting process. The microstructure and crystallography were characterized by X-ray diffraction, optical microscopy and transmission electron microscopy. The anisotropies of hardness and indentation fracture toughness were assessed by making measurements along different crystallographic directions on both transverse and longitudinal sections. While the hardness did not vary appreciably between the two orientations, the fracture toughness was observed to be highly anisotropic. Toughening behavior was observed on longitudinal sections with crack deflection and bridging mechanisms apparent. Cracks were difficult to initiate on transverse sections along directions perpendicular to the growth direction, but for 20 N loads an indentation fracture toughness of 11 MPa\(\sqrt m \) could be measured.

Wet chemical methods involving ultrasound and amide solvents were used to purify and separate large bundles of single-walled carbon nanotubes (SWNTs) into individual nanotubes that could then be transported to silicon or mica substrates. The SWNTs studied were produced by the arc-discharge process. Dry oxidation was used in an initial step to remove amorphous carbon. Subsequently, two acid purification schemes were investigated (HCl- and HNO(3)-reflux) to remove the metal growth catalyst (Ni-Y). Finally, ultrasonic dispersion of isolated tubes into either N,N-dimethylformamide (DMF) or N-methyl-2-pyrrolidone (NMP) was carried out. Raman scattering, atomic force microscopy (AFM), and electron microscopy were used to study the evolution of the products. Raman scattering was used to probe possible wall damage during the chemical processing. We found that both HCl and HNO(3) could be used to successfully remove the Ni-Y below approximately 1 wt %. However, the HNO(3)-reflux produced significant wall damage (that could be reversed by vacuum annealing at 1000 degrees C). In the dispersion step, both amide solvents (DMF and NMP) produced a high degree of isolated tubes in the final product, and no damage during this dispersion step was observed. HNO(3)-refluxed tubes were found to disperse the best into the amide solvents, perhaps because of significant wall functionalization. AFM was used to study the filament diameter and length distributions in the final product, and interesting differences in these distributions were observed, depending on the chemical processing route.

Grain boundary segregation of yttrium in titanium dioxide is studied systematically as a function of dopant concentration. Local grain boundary defect chemistry is quantitatively determined by analytical transmission electron microscopy and compared to equilibrium space-charge segregation models that incorporate both the electrostatic and elastic strain-energy driving forces for solute segregation. The thermodynamic models show that the elastic strain-energy driving force dominates in this system and that the electrostatic driving force contributes a 10–20% correction to the total solute segregation. In comparison to the experimental results, the theoretical models provide good predictions for several grain boundary parameters including local stoichiometry, solute interfacial excess and space-charge layer thickness.

Titania nanotubes synthesized by a soft chemical process are described, having diameters of 8 nm to 10 nm and lengths ranging from approximately 0.1 μm to 1 μm. X-ray diffraction studies show the structure of the as-prepared nanotubes is the same as that of the starting anatase TiO2nanoparticles. Energy-dispersive x-ray analysis and electron energy loss spectroscopy studies further indicate that the as-prepared nanotubes are composed of titania. Studies using transmission electron microscopy verified that the nanotubes are formed during alkali treatment, with subsequent acidic treatments having no effect on nanotube structure and shape.

Ceramic/metal interfaces have vast technological significance and are used in a variety of applications. This has prompted a concerted effort to develop fundamental structure/property relationships for these structures. This article critically reviews recent advances in complementary experimental and theoretical studies of ceramic/metal interfaces to provide an overview of progress made towards developing these relationships. In particular, the focus is on the structure, characterization, and modeling of non-reactive, bulk ceramic/metal interfaces. This includes determining interface atomic structure and chemistry and investigating impurity segregation to the interfaces. Additionally, the most important advances in the experimental and theoretical modeling of interfacial structure and chemistry are reviewed and comments are provided on the future outlook of this field.

Structural defects formed on {111} planes of BaTiO3 during the degradation of high performance multilayer Ni–BaTiO3 X7R ceramic capacitors are studied using transmission electron microscopy and electron energy loss spectroscopy (EELS). Regular pseudocubic barium titanate grains are present in as-produced (virginal) base-metal electrode capacitors. However, there is a coexistence of regular, modulated, and long-range ordered structures in intentionally electrically degraded devices. The EELS analysis demonstrates that the concentration of oxygen vacancies in barium titanate with modulated or ordered structures is higher than that in the regular perovskite grains. The clustering or accumulation of oxygen vacancies in the structural framework of BaTiO3 gives rise to the formation of new metastable structures. These observations are consistent with earlier models for degradation, but demonstrate that the details of the process may be more complex than originally assumed. Here we introduce new details on the n...

Gallium phosphide nanowires with a most probable diameter of approximately 20.0 nm and more than 10 microns in length have been synthesized by pulsed laser vaporization of a heated GaP/5% Au target. The morphology and microstructure of GaP nanowires have been investigated by scanning electron microscopy and transmission electron microscopy. Twins have been observed along the crystalline nanowires, which have a growth direction of [111]. Raman scattering shows a 4 cm-1 downshift of the longitudinal optical phonon peak in the nanowire with respect to the bulk; the transverse optical phonon frequency and line width are, however, the same as in the bulk. The quantum confinement model first proposed by Richter et al. cannot explain the observed behavior of the Raman modes.

An ethanol soluble protein (zein) can be extracted from maize meal. Development of a cost effective protein recovery process requires that the extracted maize particles be separated from the extract. We have previously shown that the particles can be settled into a water layer, through a stagnant interface, with low dilution of the protein-containing extract liquid. In this article, we describe testing done to develop settling tank base inclinations that enable the settled particles to be pumped from the tank as rapidly as they settle to the water layer. Ethanol extracts were pumped to one side of an ethanol solution layer floating on a water layer. The ethanol solution was kept at a constant height by pumping from a port opposite and higher than the inlet port and by maintenance of a constant water layer height. The solid particles in the extract settled into the water. Water was continuously pumped to and from the tank. Laminar water flow alone did not remove the particles at the lowest sustainable extract feed rate. Particles could be pumped out of the tank at rates equal to practical rates of extract feed when they settled on a base inclined 35° to the horizontal. The rate of extract liquid entrainment by the settling particles was determined from measurements of the mass of the solids settled into the water layer and the density of the dilute ethanol solution pumped from the bottom of the tank. The mass ratio of the extract liquid lost:solid particle settled was similar to the corresponding ratio for decanter centrifugation. Settling promises to be a cost-effective method of separating extracted particles from alcoholic extracts with low extract liquid dilution.

The rapidly expanding telecommunications market has led to a need for advanced rf integrated circuits. Complex rf- and mixed-signal system-on-chip designs require accurate prediction early in the design schedule, and time-to-market pressures dictate that design iterations be kept to a minimum. Signal integrity is seen as a key issue in typical applications, requiring very accurate interconnect transmission-line modeling and RLC extraction of parasitic effects. To enable this, IBM has in place a mature project infrastructure consisting of predictive device models, complete rf characterization, statistical and scalable compact models that are hardware-verified, and a robust design automation environment. Finally, the unit and integration testing of all of these components is performed thoroughly. This paper describes each of these aspects and provides an overview of associated development work.

The potential for highly integrated radio frequency (RF) and mixed-signal (AMS) designs is today very real with the availability cost-effective scaled silicon-germanium (SiGe) process technologies. However, the lack of effective parasitic modeling and noise mitigation significantly restrict opportunities for integration, due to a lack of computer-aided design solutions and practical guidance for designers. This tutorial paper provides a broad in-depth coverage of the key technical areas that designers need to understand in estimating and mitigating IC parasitic effects. A detailed analysis of the parasitic effects in passive devices, the interconnect (including transmission line modeling) and substrate impedance, and isolation estimation is presented-referencing a large number of key publications in these areas.

Well-aligned nitrogen-doped multiwall carbon nanotube arrays have been successfully grown over large areas on quartz and silicon wafers by floating-catalyst chemical vapor deposition at low temperatures (600 degrees C). These nitrogen-including nanotubes, derived from pyridine-ferrocene mixtures, have smaller outer diameters but larger inner diameters compared with carbon nanotubes grown from a xylene-ferrocene mixture under similar conditions. The N-doped nanotubes exhibit bamboo-like structures in the core. Elemental analysis and electron energy loss spectroscopy analysis show that the as-prepared nanotubes contain as much as 2.62 wt.% N, with most of the N concentrated in the inner few shells of the nanotube. Such large-scale arrays of well-aligned N-doped nanotubes on silicon wafers have a current density as high as 23.8 mA/cm2 at an applied electric field of 17 V/micron, which can be further improved by patterning the tubes and coating the silicon substrate with a conductive thin metal film for the fabrication of flat panel displays.

The stability of titanium oxide nanotube arrays at elevated temperatures was studied in dry oxygen as well as dry and humid argon environments. The tubes crystallized in the anatase phase at a temperature of about 280 °C irrespective of the ambient. Anatase crystallites formed inside the tube walls and transformed completely to rutile at about 620 °C in dry environments and 570 °C in humid argon. No discernible changes in the dimensions of the tubes were found when the heat treatment was performed in oxygen. However, variations of 10% and 20% in average inner diameter and wall thickness, respectively, were observed when annealing in a dry argon atmosphere at 580 °C for 3 h. Pore shrinkage was even more pronounced in humid argon environments. In all cases the nanotube architecture was found to be stable up to approximately 580 °C, above which oxidation and grain growth in the titanium support disrupted the overlying nanotube array.

Here, we apply aberration-corrected scanning transmission electron microscopy to quantify chemical ordering in the relaxor Pb(Mg1∕3Nb2∕3)O3 (PMN). We find that contrary to the prevailing model of a binary distribution of chemically ordered regions within a disordered matrix, the degree of ordering smoothly varies within an ordered domain and approaches a minimum at anti-phase boundaries. These results provide direct insight into the nature of cation ordering in this important prototypical relaxor material.

Objective: This study examined whether early or late processes in semantic networks were abnormal in women with a diagnosis of schizotypal personality disorder. The N400 component of the EEG event-related potentials was used as a probe of semantic processes. Method: Word pairs were presented with short and long stimulus-onset asynchronies to investigate, respectively, early and late semantic processes in 16 women with schizotypal personality disorder and 15 normal female comparison subjects. Event-related potentials were recorded in response to the last words in a pair. Results: With the short stimulus-onset asynchrony, the N400 amplitude was less negative in the schizotypal personality disorder group than in the normal comparison group. No group differences were found with the long stimulus-onset asynchrony. Conclusions: The finding of a less negative than normal N400 amplitude with the short stimulus-onset asynchrony in women with schizotypal personality disorder supports the hypothesis that persons with this disorder evince an overactivation of semantic networks. The absence of group differences with the long stimulus-onset asynchrony, which is primarily sensitive to processes involved in context integration, suggests that in this group of schizotypal personality disorder subjects, additional demands on working memory may be necessary to bring out the semantic dysfunction.

BACKGROUND: Umbilical cord blood is an alternative peripheral blood progenitor cell source for patients who need transplantation. A presumed advantage of cord blood is the ability to increase minority recruitment. STUDY DESIGN AND METHODS: The racial composition of five member cord blood banks of the National Marrow Donor Program (NMDP) was compared, representing 9020 cord blood donors with NMDP marrow donors from comparable geographic areas, representing 417,676 donors. Cord blood and marrow donors self-reported racial designations on questionnaires. Donor statistics were compared with baseline racial data of deliveries from participating hospitals for cord blood donors and with geographic census data for marrow donors. RESULTS: The California, Florida, and Massachusetts cord blood banks recruited a lower percentage of minorities than the corresponding marrow donor centers. In New York and Colorado, minority recruitment was equivalent. In California, Florida, Massachusetts, and New York, the cord blood banks recruited a lower percentage of minorities than those delivering at the respective hospitals. The cord blood banks in California, Colorado, Florida, and Massachusetts recruited a lower percentage of minorities compared with delivery data than the corresponding marrow donor centers compared with census population (p < 0.001). In New York, the percentages were similar. CONCLUSION: The problem of insufficient minority recruitment of cord blood has not yet been solved. Better strategies are needed to recruit minority donors.

Low-cost extraction of maize protein using ethanol at the front end of a dry grind ethanol plant has been discussed in recent articles. Thorough recovery of (alcoholic) extract from the extracted maize is essential to make the process economical and to prevent the ethanol from interfering with liquefaction enzymes or fermentation organisms where the solid residues are to be subsequently reduced to glucose and finally fermented to ethanol. Because the particles will be converted in water it is unnecessary to dry them, if a (miscible) liquid/liquid miscible displacement method can be used. Therefore, three methods of displacing extract liquid from the extracted corn particles were tried using (1) packed bed displacement, (2) centrifugation with rinsing, and (3) gravitational settling into water. Displacing extract (liquid) from a stationary bed of milled corn extract was too slow to be practical. This finding should discourage the use of similar techniques based on stationary layers of extracted corn. Continuous centrifugation, with rinsing by fresh ethanol solution, was effective at recovering protein in the extract with rinse rates comparable to extract feed rates. Settling the extracted corn into water appears to be the most feasible method of separation, requiring low extract dilution and inexpensive equipment.

Individuals with schizophrenia spectrum disorders evince similar genetic, neurotransmitter, neuropsychological, electrophysiological, and structural abnormalities. Magnetic resonance imaging (MRI) studies have shown smaller gray matter volume in patients with schizotypal personality disorder than in matched comparison subjects in the left superior temporal gyrus, an area important for language processing. In a further exploration, the authors studied two components of the superior temporal gyrus: Heschl's gyrus and the planum temporale.MRI scans were acquired from 21 male, neuroleptic-naive subjects recruited from the community who met DSM-IV criteria for schizotypal personality disorder and 22 male comparison subjects similar in age. Eighteen of the 21 subjects with schizotypal personality disorder had additional comorbid, nonpsychotic diagnoses. The superior temporal gyrus was manually delineated on coronal images with subsequent identification of Heschl's gyrus and the planum temporale. Exploratory correlations between region of interest volumes and neuropsychological measures were also performed.Left Heschl's gyrus gray matter volume was 21% smaller in the schizotypal personality disorder subjects than in the comparison subjects, a difference that was not associated with the presence of comorbid axis I disorders. There were no between-group volume differences in right Heschl's gyrus or in the right or left planum temporale. Exploratory analyses also showed a correlation between poor logical memory and smaller left Heschl's gyrus volume.Smaller left Heschl's gyrus gray matter volume in subjects with schizotypal personality disorder may help to explain the previously reported abnormality in the left superior temporal gyrus and may be a vulnerability marker for schizophrenia spectrum disorders.

The structure of the cubic-ZrO2 symmetrical tilt Σ5 (310)/[001] grain boundary is examined using density functional theory within the local density and pseudopotential approximations. Several pristine stoichiometric grain-boundary structures are investigated and compared with Z-contrast scanning transmission electron microscopy and electron energy loss spectroscopy results. The lowest-energy grain-boundary structure is found to agree well with the experimental data. When Y3+ is substituted for Zr4+ at various sites in the lowest-energy grain-boundary structure, the calculations indicate that Y3+ segregation to the grain boundary is energetically preferred to bulk doping, in agreement with experimental results.

The effect of pore size and uniformity on the humidity response of nanoporous alumina, formed on aluminum thick films through an anodization process, is reported. Pore sizes examined range from approximately 13 to 45 nm, with a pore size standard deviations ranging from 2.6 to 7.8 nm. The response of the material to humidity is a strong function of pore size and operating frequency. At 5 kHz an alumina sensor with an average pore size of 13.6 nm (standard deviation 2.6 nm) exhibits a well-behaved change in impedance magnitude of 103 over 20% to 90% relative humidity. Increasing pore size decreases the humidity range over which the sensors have high sensitivity and shifts the operating range to higher humidity values. Cole–Cole plots of 5 to 13 MHz measured impedance spectra, modeled using equivalent circuits, are used to resolve the effects of water adsorption and ion migration within the adsorbed water layer. The presence of impurity ions within the highly ordered nano-dimensional pores, accumulated during the anodization process, appear highly beneficial for obtaining a substantial variation in measured impedance over a wide range of humidity values.

Silicon–germanium (SiGe) heterojunction bipolar transistor (HBT) BICMOS technology is a stable, ultra-high performance, semiconductor technology capable of supporting mixed-signal, very large-scale integration (VLSI) circuit designs for a variety of emerging communication applications. This technology is supported by a computer-aided design (CAD) system that supports a variety of high-performance circuit designs, mixed-signal circuit block reuse, and the ability to accurately predict circuit performance at the highest frequencies. This paper summarizes the progress this technology has made in recent years in moving from the research laboratory to a production environment. We also specifically address performance, operating voltage, reliability and integration considerations for using 100–200 GHz SiGe HBTs in high-speed (10–40 Gb/s) network ICs, an application space previously only addressed by InP technology. All indications are that SiGe will be very successful at addressing this new application space, and all facets of the networking IC market.

Fabrication of nanoporous TiO2 thin films through Benard-Marangoni convection is reported. Variation of pore size and morphology in the sol-gel deposited metal-oxide films is investigated as a function of ambient humidity and air flow velocity during film drying, sol concentration, and addition of water/acid to the sol.

Studies of schizotypal personality disorder (SPD) are important because the condition is genetically related to schizophrenia and because data accumulating to confirm its biological underpinnings are challenging some traditional views about the nature of per-sonality disorders. This review of 17 structural imaging studies in SPD indicates that individuals with this disorder show brain abnormalities in the superior temporal gyrus, parahippocampus, temporal horn region of the lateral ventricles, corpus callosum, thalamus, and septum pellucidum, as well as in total cerebrospinal fluid volume, similar to those seen in persons with schizophrenia. Differences between SPD and schizophrenia include lack of abnormalities in the medial temporal lobes and lateral ventricles in SPD. Whether the normal volume, and possibly normal functioning, of the medial temporal lobes in individuals with SPD may help to suppress psychosis in this disorder remains an intriguing but still unresolved question. Such speculation must be tempered due to a paucity of studies, and additional work is needed to confirm these preliminary findings. The imaging findings do suggest, however, that SPD probably represents a milder form of disease along the schizophrenia continuum. With further clarification of the neuroanatomy of SPD, researchers may be able to identify which neuroanatomical abnormalities are associated with the frank psychosis seen in schizophrenia.

Prolamine-rich, water insoluble proteins (zeins) can be extracted from milled maize by vigorous mixing in heated ethanol solutions. Whenever solvent extraction is used process cost considerations require that all the solvent be recovered. Because of the low zein content of maize rinsing extract liquid from the extracted maize particles must be done in a way that minimizes dilution. The solid mass fraction of milled grain slurry that can be pumped is 0.25 or less. Because the mass fraction of zein in maize is only approximately 0.05, the zein mass fraction of a batch extract will be less than 0.015. To increase the zein concentration, a batch extract (liquid and fines) can be repeatedly separated from the extracted solid particles and used to extract fresh milled grain. A series of batch extractions with extract reuse can approach the performance of a continuous counter-current solids/liquid extraction, which would be preferable at a commercial scale. Extract reuse is constrained by losses of liquid with the extracted grain and by reductions of the extracting capacity of the extract due to the increasing solute or fines content. By examining the extract composition and yield of a series of batches, it is possible to estimate the zein concentration that could be achieved in a continuous, countercurrent process and to examine effects of higher zein concentrations on extraction that would be inaccessible with a single batch. The centrifugate concentrations for a series of maize extractions in which the extracted maize and extract solution were cooled prior to centrifugation were analyzed. The data were fit with a model based on a maximum zein concentration in the extract. The fit indicates that the protein content of the liquid centrifugate will not exceed 2% for any series of similar batch extractions, by using centrifugation to separate the maize from the extraction slurry after cooling it to ambient temperature. This contrasts with concentrations of zein of 10% or more achieved by extracting corn gluten using similar conditions. Although the concentration of zein in gluten is higher we believe the concentration difference is mainly due to chemical changes to the zein that take place in the gluten production and the methods used to extract zein from gluten.

Rigorous assessments of program quality are uncommon in developing countries. We evaluated the quality of the two-week, volunteer-facilitated, caregiver-child rehabilitation “hearth,” or nutrition education and rehabilitation program (NERP), sessions in Save the Children's integrated nutrition program in Viet Nam. Field workers observed attendance, food contribution, food preparation, meal consumption, health message delivery, hygiene, and weighing at 240 NERP days at 59 NERP centers during seven months of implementation. Participation in cooking NERP meals (75.8%), washing mothers' and children's hands (75.7% and 81.6%, respectively), and weighing (74.5% on days 1 and 12) were high, but attendance rates (50.3%), food contributions (20.3%), and health message delivery (20.0%) were lower than expected, all with wide variation among communes, ecology, NERP day, and NERP round. Contrary to protocol, food was often delivered to malnourished children who stayed at home to accommodate caregivers' workloads and other constraints. While home-delivery of food prevented caregivers from learning from each other in a group, it did bring “tangible messages” (i.e., a large serving size of a new food) to the doorstep. Health volunteers were wise to stress active learning over repetitive message delivery. In summary, these NERPs were probably typical of previous NERPs although comparable quality measures are lacking. Despite imperfect implementation, the NERP's active-learning and local problem-solving helped achieve measurable impact on growth, diet, morbidity, and empowerment despite uncommon program challenges, such as uncharacteristically low baseline levels of malnutrition and high population dispersion. Regular quality monitoring may enhance impact even further.

The interface of electrode materials in contact with solid-state electrolytes is of current interest for the development of devices with high energy density and good safety. In-situ transmission electron microscopy (TEM) of energy storage materials allows for the detailed study of structure-property relationships near solid interfaces during electrochemical charge and discharge. Here, we will describe the design of an in-situ TEM platform to investigate the structure-property relationship of a model energy storage oxide, V2O5, in contact with a state-of-the-art solid-state electrolyte Li7La3Zr2O12 (LLZO). The cell was fabricated by the atomic layer deposition (ALD) of V2O5 (~ 50 nm thick) onto the electrolyte and subsequent focused ion beam (FIB) milling and lift-out of a micron-long electrode/electrolyte architecture. The lithium metal anode was electrochemically deposited directly onto the gold electrode of an in-situ TEM chip. Assembly of the electrochemical cell was performed in a scanning electron microscope using a micromanipulator. Bright-field TEM and electron energy loss spectroscopy (EELS) showed that the deposited V2O5 layer formed a well-defined interface with LLZO and this allowed for the determination of the vanadium oxidation state. This work demonstrates the fabrication of a platform for the in-situ TEM study of materials at electrode/solid-state electrolyte interfaces that can readily be adapted to other types of solid state battery chemistries.

Anelastic materials exhibit gradual full recovery of deformation once a load is removed, leading to dissipation of internal mechanical energy. As a consequence, anelastic materials are being investigated for mechanical damping applications. At the macroscopic scale, however, anelasticity is usually very small or negligible, especially in single-crystalline materials. Here, we show that single-crystalline ZnO and p-doped Si nanowires can exhibit anelastic behaviour that is up to four orders of magnitude larger than the largest anelasticity observed in bulk materials, with a timescale on the order of minutes. In situ scanning electron microscope tests of individual nanowires showed that, on removal of the bending load and instantaneous recovery of the elastic strain, a substantial portion of the total strain gradually recovers with time. We attribute this large anelasticity to stress-gradient-induced migration of point defects, as supported by electron energy loss spectroscopy measurements and also by the fact that no anelastic behaviour could be observed under tension. We model this behaviour through a theoretical framework by point defect diffusion under a high strain gradient and short diffusion distance, expanding the classic Gorsky theory. Finally, we show that ZnO single-crystalline nanowires exhibit a high damping merit index, suggesting that crystalline nanowires with point defects are promising materials for energy damping applications.

Titanium oxide nanotubes were fabricated by anodic oxidation of a pure titanium sheet in an aqueous solution containing 0.5 to 3.5 wt% hydrofluoric acid. These tubes are well aligned and organized into high-density uniform arrays. While the tops of the tubes are open, the bottoms of the tubes are closed, forming a barrier layer structure similar to that of porous alumina. The average tube diameter, ranging in size from 25 to 65 nm, was found to increase with increasing anodizing voltage, while the length of the tube was found independent of anodization time. A possible growth mechanism is presented.

The cubic-ZrO2 (100) ‖ NiO (111) interface provides an opportunity for comparison between atomic-scale measurements, atomistic simulations, and theoretical electronic structures. High-resolution electron microscopy indicates that the oxides share a common oxygen layer and that the small lattice strain is largely taken up by NiO near the interface. Using simple Coulomb plus Buckingham-type interatomic potentials, we are able to provide a more focused picture, revealing two types of boundary. The lowest energy interface is highly planar, almost ideal in structure; there is a second interface, of higher energy, that shows a rumpled structure with strain taken up by deformation of nickel chains. Depth profiling of atomic site energies permits calculation of interface versus bulk and surface energies, and it shows that the interface effects penetrate only two to three atomic layers. Embedded cluster density functional studies of bulk and interface-region sites permit the characterization of perturbations of electronic density around the boundaries.

In this work we report on the complex permittivity spectra and electrical conductivity of both as-fabricated and graphitized multiwall carbon nanotubes (MWNTs). The high-temperature annealing removes the Fe3C catalyst particles present in the as-fabricated material, enabling the intrinsic MWNT properties to be measured. The permittivity spectra of 1 wt % MWNT-polystyrene composite films are measured from 75 to 1875 MHz. Comparison of measurements with an appropriate effective medium model shows that the residual catalyst inclusions in the core of the nanotube increase the average electrical conductivity by approximately a factor of 3.5.

This paper demonstrates the viability of in-situ transmission electron microscopy for studying the deformation mechanisms of polymer nano-composites. In-situ straining studies are performed on carbon multiwalled nanotube (MWNT)-polystyrene composite films. The experiments show that load transfer across the nanotube-polystyrene interface is operative well into the plastic deformation regime of the composite film. The MWNTs are observed to bridge cracks propagating through the polystyrene, providing closure stresses across the crack wake. Although some MWNTs fracture by either a sword-in-sheath mechanism or transverse shear fracture, most of the MWNTs eventually debond at the MWNT-polymer interface and subsequently pull out of the matrix.

In this work, we present a systematic study of the effects of graphitization on the structural perfection of multiwalled carbon nanotubes. High purity nanotubes were produced by a low temperature CVD method and subsequently annealed at temperatures between 1600 and 3000°C. The nanotubes were characterized for chemical purity, interlayer spacing, and defect healing. The graphitization procedure was found to remove residual metal catalyst in the nanotubes and reduce the wall defects as reflected in a reduced interlayer spacing between the graphene shells. Graphitization presents a low-cost, commercially viable method of purifying and ordering multiwall carbon nanotubes.

A magnetically-driven method for controlling nanodimensional porosity in sol-gel-derived metal–oxide films, including TiO2, Al2O3, and SnO2, coated onto ferromagnetic amorphous substrates, such as the magnetically-soft Metglas1 alloys, is described. On the basis of the porous structures observed dependence on external magnetic field, a model is suggested to explain the phenomena. Under well-defined conditions it appears that the sol particles coming out of solution, and undergoing Brownian motion, follow the magnetic field lines oriented perpendicularly to the substrate surface associated with the magnetic domain walls of the substrate; hence the porosity developed during solvent evaporation correlates with the magnetic domain size.

Zein can be extracted from maize (Zea mays) using ethanol solutions, and recovered from the extract by diluting with water. Dilution to 40% ethanol will precipitate a mixture of zein and maize lipid with ∼15% lipid. For possible zein applications, such as film production, purer zein is required. Most of the lipid can be removed from the precipitate by selective re-extraction with hexane or ethanol, but this is expensive. A precipitate containing 90% or more of the protein in the extract, with less than 10% lipid, can be obtained by diluting the extract in stages. An initial dilution will precipitate a solid with 75% or more lipid, this precipitate can be centrifuged from the extract and the centrifugate diluted to precipitate a solid of 70% or more zein. The mass and composition of solid centrifuged from a maize extract that was diluted in several steps to characterize the composition of precipitates so formed. The lipid content of a zein product precipitated from an extract diluted from 55% ethanol to 50% is significantly lower than the content of precipitate of an extract diluted in a single step to 40% ethanol.