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Several research teams have previously traced patterns of emerging conduct problems (CP) from early or middle childhood. The current study expands on this previous literature by using a genetically-informed, experimental, and long-term longitudinal design to examine trajectories of early-emerging conduct problems and early childhood discriminators of such patterns from the toddler period to adolescence. The sample represents a cohort of 731 toddlers and diverse families recruited based on socioeconomic, child, and family risk, varying in urbanicity and assessed on nine occasions between ages 2 and 14. In addition to examining child, family, and community level discriminators of patterns of emerging conduct problems, we were able to account for genetic susceptibility using polygenic scores and the study's experimental design to determine whether random assignment to the Family Check-Up (FCU) discriminated trajectory groups. In addition, in accord with differential susceptibility theory, we tested whether the effects of the FCU were stronger for those children with higher genetic susceptibility. Results augmented previous findings documenting the influence of child (inhibitory control [IC], gender) and family (harsh parenting, parental depression, and educational attainment) risk. In addition, children in the FCU were overrepresented in the persistent low versus persistent high CP group, but such direct effects were qualified by an interaction between the intervention and genetic susceptibility that was consistent with differential susceptibility. Implications are discussed for early identification and specifically, prevention efforts addressing early child and family risk.
A feasibility test at the Naval Research Laboratory has shown that a miniature X-ray Fluorescence (XRF) sensor can be constructed for the cone penetrometer. Such a sensor would have detection limits for heavy metal contaminants in soils of a few parts per million. The next step is to demonstrate the capabilities of such a sensor in the cone penetrometer. A sensor for this purpose is being constructed and will be tested both in the laboratory and in the field. The XRF sensor will be capable of evaluating the in-situ detection limits and field screening (semi-quantitative) capabilities of x-ray fluorescence and can be transitioned to field activities for further evaluation and feedback. The sensor will consist of a miniature x-ray tube and an x-ray detector, together with appropriate apertures and x-ray filters, in a custom fabricated section of penetrometer pipe. The sensor will use commercially available components. High voltage and signal cables will couple the sensor to electronics in the truck. Boron carbide will be used for the x-ray windows which protect the sensor components from soil abrasion.
Appearance potential spectroscopy has been practiced for many years. In essence, it simply involves ramping the energy of the exciting quanta across excitation edges and observing the onset of a signal. Because of the relative simplicity with which the energy can be controlled, electrons have been the conventional quanta employed. The signals which have "appeared", characteristic of the atoms being studied, have been either Auger electrons or x-ray. The literature is replete with references to appearance potential measurements; the applications have, for the most part, demonstrated interesting physics, but analytical measurements have not been numerous.
The cone penetrometer is a well-established method for exploring soil types whereby a smalldiameter pipe with a hardened cone tip is pushed hydraulically into the ground. The system can be equipped with sensors to detect soil contamination. We have investigated the development of an x-ray fluorescence (XRF) sensor to be deployed via this system.
The principal uncertainties in the application of XRF to metals detection in the cone penetrometer are the detection limits and the accuracy of a sensor built in such a confined geometry. A laboratory mock-up was constructed to investigate the performance of such a sensor. An x-ray tube operated at very low power was coupled to an electrically cooled Si(Li) detector. The x-ray path lengths were kept short and an aperture and incident x-ray filter similar to those appropriate for a penetrometer sensor were used.
Spectra were collected on a series of Standard Reference Material soils from the National Institute of Standards and Technology consisting of soils with various levels of metal contamination. The detection limits were determined for the metals present in the soils and were comparable to the solid waste regulatory limits. Quantitative measurements were compared to the NIST certified values both without matrix correction and using the fundamental parameters correction method. Results were generally within 10% of the certified values.
10 years after writing the essay “equation for black people on stage” I’m standing at the same crossroads asking the same questions. No sweat. Sometimes you can walk a hundred miles and end up in the same spot. The world ain’t round for nothing right? What is a black play? The definition is housed in the reality of two things that occurred recently and almost simultaneously: 26 August 05, playwright scholar poet king August Wilson announces he is dying of cancer, and hurricane Katrina devastated the Gulf Coast. It feels like judgment day. What I’m talking about today is the same and different. I was tidy then. And now Im tidier. Tidier today like a tidal wave.
What is a black play?
A black play is angry.
A black play is fierce.
A black play is double voiced but rarely confused.
A black play got style.
A black play is of the people by the people and for the people.
A black play is smooth but not slick, heavy but not thick, can’t be tamed, often does not comb its hair, wipes its mouth with the back of its black hand or with a linen napkin whichever is more readily available.
A black play is late.
A black play is RIGHT ON and RIGHT ON TIME.
A black play is deep.
A black play is armed / to the teeth.
A black play bows to god then rows the boat ashore.
A black play makes do if it got to / fights / screams / sings / dreams / WORKS IT / talks in code and tells it like it is ALL UP IN YA FACE.
A black play gives you five.
A black play is robust and alive.
A black play is in the house and looking good, too.
Nucleation and growth has been studied during tungsten (W) atomic layer deposition (ALD) on oxide surfaces. Auger electron spectroscopy (AES) was utilized to examine the deposition of W during the sequential (A) WF6 and (B) Si2H6 reaction cycles that define W ALD. The AES results displayed an initial nucleation period of ∼10 AB cycles to deposit one tungsten monolayer on SiO2. Subsequently, the W and Si AES signals grew and oscillated dramatically versus WF6 and Si2H6 exposures. The increase in the W AES signal in the growth region was consistent with a W ALD growth rate of 3.5 Å per AB cycle. An examination of the oxygen and tungsten AES signals versus AB cycles indicated that W ALD displayed nearly ideal “layer-by-layer”, Frank- van der Merwe growth after the nucleation period. On Al2O3, the AES results displayed a much shorter nucleation period for W ALD. Only 3 AB cycles were required to deposit one tungsten monolayer. Subsequently, the tungsten film grew at a rate of 3.6 Å per AB cycle. The initial nucleation period and growth mechanism during ALD are important because they will affect the roughness of the resulting ALD film.
Anodized Aluminum Oxide (AAO) based micro-channel plates (MCP) are fabricated in order to develop economical large-area photodetectors. Commercially available glass capillary array has a limitation to reach channel diameter below ~10 microns. However, smaller channel diameter is desired for better spatial and fast timing resolution. AAO based MCP is a good candidate to produce channel diameter less than 10 um by taking advantage of the nano-scale intrinsic pores during etching process. In this study, various channel diameters are fabricated with use of lithographic patterning techniques and wet etching; and characterized with optical, atomic force, and scanning electron microscopies. The channel diameter, channel length and related aspect ratio, as well as the open area are varied in order to maximize the MCP photon amplification.
Thick coatings of Y-Ba-Cu-oxide superconductors have been prepared by plasma spray processing. This paper reports a number of the important properties of coatings sprayed at two different power levels. The microstructure, porosity, and chemical composition of the coatings were studied in their as-sprayed and annealed states. Critical current and magnetic susceptibility measurements were made on the annealed coatings. X-ray diffraction was used to identify non-superconducting phases present in the coatings and to determine the superconducting phase's lattice constants.
Atomic layer deposition (ALD) is ideal for applying precise, conformal coatings over nanoporous materials. We have recently used ALD to coat two nanoporous solids: anodic aluminum oxide (AAO) and silica aerogels. AAO possesses hexagonally ordered pores with diameters d∼10 nm and thicknesses L∼70 microns. The AAO membranes were coated by ALD with successive layers of A1203, TiO2 and V2O5 to fabricate catalytic membranes. SEM, TEM and EDAX analysis of the membranes demonstrate that the ALD layers uniformly coat the extremely high aspect ratio (L/d∼104) AAO pores. These catalytic membranes show remarkable selectivity in the oxidative dehydrogenation of cyclohexane. Additional AAO membranes coated with ALD Pd films show promise as hydrogen sensors. Silica aerogels have the lowest density and highest surface area of any solid material. Consequently, these materials serve as an excellent substrate to fabricate novel catalytic materials and gas sensors by ALD. In this study, both thin film and monolithic aerogels were coated by ZnO ALD and the properties of the aerogels were investigated as a function of the coating thickness.
Extended x-ray absorption fine structure measurements of a Co78Cr22 film were performed using normal and glancing incident radiation in order to investigate, respectively, the in-plane and out-of-plane local structure and chemistry. The Fourier transformed EXAFS data of the in-plane and out-of-plane structures around the Co and Cr atoms illustrates the presence of an anisotropy. Analysis of the local environments around Co for the two sample orientations indicates the presence of Co-enriched clusters, while similar studies of the Cr environments indicate preferential ordering parallel to the film plane. Quantitative analysis of the higher order Fourier transform peaks shows a greater amount of disorder perpendicular to the film plane beyond that expected for a textured hcp film. These results are consistent with earlier reports of a high density of stacking faults or twinning planes perpendicular to the growth axis, supporting the interpretation that a platelet-like texturing exists within the columnar microstructure.
Using a case study methodology, we examined the implementation of a nursing flow sheet system in the trauma center of a large, not-for-profit, teaching hospital. Findings add new insights to the existing body of knowledge in the information technology and medical informatics fields. First, results reveal that the success of clinical information systems requires a proactive stance where key actors anticipate and address the challenges ahead and capitalize on opportunities. Second, empirical evidence indicates that project outcomes ultimately depend on how the implementation process is managed and what the organization and its members do with the system once it is introduced. Finally, the case at hand shows that the nature and overall quality of the implementation strategy can be largely predicted by the key actors involved in the project, given their own background, skills, interest, and level of motivation.