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Several phosphatovanadium cluster compounds with embedded halide ions were investigated. They include the chloride (VO)6(O3POSiMe3)8Cl and the fluoride Et4P (sup +) (V2O3)2(O3PPh)4F (sup -) and the methylphosphato and butyl phosphato analogues of the fluoride compound. Both enable the oxidation of 1,4-cyclohexadiene to benzene in hot pyridine mixture. In addition, both have only three oxygen atoms per phosphorus for cluster bonding, thus allowing the phosphorus centers to serve as sites of positive Gaussian curvature.

Recrystallization of the solid [[Cd.sub.10][S.sub.4][([SC.sub.6][H.sub5]).sub.12] from a solution of pyridine and N, N-dimethylformamide (DMF) results in the formation of the cluster [Cd.sub.32][S.sub.14] [([SC.sub.16][H.sub.5]).sub.36][center dot][DMF.sub.4] as pale yellow cubes. The structure consists of an 82-atom CdS core that is a roughly spherical piece of the cubic sphalerite lattice 12 angstroms in diameter. The four corners of the lattice are capped by hexagonal wurtzite-like CdS units, which results in an overall tetrahedral cluster 15 angstroms in diameter. This cluster dissolves intact in tetrahydrofuran where its absorption spectrum reveals a sharp peak at 358 nanometers at room temperature and its emission spectra show a strong broad band at 500 nanometers., The use of very small molecular clusters as synthetic precursors to bulk, extended solids interests both the physics[1] and chemistry [2] communities. In the particular case of semiconductor materials, the [...]

This paper describes the automation and control of a 'manual'synchromesh gearbox in a form suitable for use in an electric or hybrid-electric vehicle. Such a computer controlled transmission system allows full integration and control of the drive train leading to improved vehicle performance. The automation process is described, and a full description given, of the computer control algorithms necessary to ensure smooth and reliable operation of the transmission system. It is shown that an up-change can be achieved in 1.4 seconds and a down-change in 1.2 seconds. These times are shown to represent maximum gear change times and details of how they can be reduced substantially are discussed. [ABSTRACT FROM PUBLISHER]

Thin, superconducting Tl-Ba-Ca-Cu-O films were grown using a two-step fabrication process which involved the growth of Ba-Ca-Cu-O films by reactive magnetron sputtering followed by ex situ high-temperature crystallization and thallination under thallium oxide vapors. Films were thallinated with both Tl2O3 and Tl2Ba2CuO6 as the source for thallium oxide vapors. Highly oriented films were obtained with the c axis perpendicular to the surface of the film. Best films had a Tc (R=0) of 104 K and a critical current density of 5×104 A/cm2 at 77 K. [ABSTRACT FROM AUTHOR]

We report a class of highly efficient electroluminescent materials based on fluorinated iridium compounds. Using aluminum as the cathode, a device, using fac-tris[5-fluoro-2(5-trifluoromethyl-2-pyridinyl)phenyl-C,N]iridium (Ir-2h) as the luminescent layer, displayed intense electroluminescence at 525 nm with an efficiency of 20 cd/A and a maximum radiance of 4800 cd/m2. Differing from the previously reported Ir(ppy)[sub 3], Ir-2h can be used in the undiluted form without the use of a charge-transporting host. This indicates that Ir-2h by itself has good enough charge-transporting properties. Photoluminescence studies at room temperature and 77 K revealed that electroluminescence originates from the metal-to-ligand charge transfer state with a quantum yield of 0.56 for Ir-2h and 0.5 for Ir(ppy)[sub 3] in toluene at room temperature. In the thin-film form, photoluminescence quantum yield of Ir-2h is a factor of 10 greater than that of Ir(ppy)[sub 3] due to the larger self-quenching effect of Ir(ppy)[sub 3]. © 2001 American Institute of Physics. [ABSTRACT FROM AUTHOR]

The distribution of soil hydraulic and physical properties strongly influences runoff processes in landscapes. Although much work has been done to quantify and predict the properties of hillslope soils, farless is known about the distribution of soil properties in valley floors. A technique that links the estimation and distribution of soil hydraulic properties in valleys, with easily identified geomorphic features, was developed along a 2 km length of a valley at Brooks Creekin New South Wales, Australia. Soil physical and hydraulic property data were collected across a set of floodplain and fan features within the valley and analysed statistically to determine if soil properties varied significantly between geomorphic features and stratigraphiclayers. The results show that the depth-averaged saturated hydraulicconductivity, Ks, of the soil varies significantly with landform: fan units have Kg values that are twice that of floodplains and colluvial toeslope deposits have Ks values four times higher than floodplains. Given the notorious variability of Ks values in space, the strong statistical separation ofsoil properties by landform, backed up by strong separation of soil particle size by landform, suggests a way forward in understanding the distribution of soil properties in valleys and their influence on catchment hydrology. [ABSTRACT FROM AUTHOR]

Background: The number of opioid-involved overdose deaths in the United States remains a national crisis. The HEALing Communities Study (HCS) will test whether Communities That HEAL (CTH), a community-engaged intervention, can decrease opioid-involved deaths in intervention communities (n = 33), relative to wait-list communities (n = 34), from four states. The CTH intervention seeks to facilitate widespread implementation of three evidence-based practices (EBPs) with the potential to reduce opioid-involved overdose fatalities: overdose education and naloxone distribution (OEND), effective delivery of medication for opioid use disorder (MOUD), and safer opioid analgesic prescribing. A key challenge was delineating an EBP implementation approach useful for all HCS communities., Methods: A workgroup composed of EBP experts from HCS research sites used literature reviews and expert consensus to: 1) compile strategies and associated resources for implementing EBPs primarily targeting individuals 18 and older; and 2) determine allowable community flexibility in EBP implementation. The workgroup developed the Opioid-overdose Reduction Continuum of Care Approach (ORCCA) to organize EBP strategies and resources to facilitate EBP implementation., Conclusions: The ORCCA includes required and recommended EBP strategies, priority populations, and community settings. Each EBP has a "menu" of strategies from which communities can select and implement with a minimum of five strategies required: one for OEND, three for MOUD, and one for prescription opioid safety. Identification and engagement of high-risk populations in OEND and MOUD is an ORCCArequirement. To ensure CTH has community-wide impact, implementation of at least one EBP strategy is required in healthcare, behavioral health, and criminal justice settings, with communities identifying particular organizations to engage in HCS-facilitated EBP implementation., (Copyright © 2020 The Authors. Published by Elsevier B.V. All rights reserved.)

In Australia, problems of dryland and stream salinity have recently become the focus of a National Action Plan. In many river catchments, preliminary stream salt load and salinity targets have been set to define maximum permissible export levels in 2015. Afforestation has been proposed as a strategy for meeting these targets, although several studies suggest that widespread commercial tree plantations are likely to deliver net dis-benefits. However, the impacts on stream salt loads of more localised tree plantings in high salt yielding areas have not been quantified. In this paper we use a simple empirical model to predict the effects of various strategic and non-strategic tree planting scenarios on flows and salt loads in the mid-Macquarie catchment, New South Wales. A simple salt routing model is then used to estimate the effect of these changes on salt loads at the end-of-valley monitoring site for the Macquarie catchment. Results suggest that widespread land management interventions will be required to meet the preliminary salt load targets for this catchment. On their own, small-scale, strategic tree planting in high salt export areas of the mid-Macquarie area will not have a significant impact on salt loads at the end-of-valley monitoring site. While widespread tree plantings may reduce salt loads in the longer term, they are likely to cause streamflow losses in the shorter term. Thus, stream salinities are expected to rise initially, due to the different response times of groundwater and surface water systems to land use change.

Widespread afforestation has been proposed as one means of addressing the increasing dryland and stream salinity problem in Australia. However, modelling results presented here suggest that large-scale tree planting will substantially reduce river flows and impose costs on downstream water users if planted in areas of high runoff yield. Streamflow reductions in the Macquarie River, NSW, Australia are estimated for a number of tree planting scenarios and global warming forecasts. The modelling framework includes the Sacramento rainfall-runoff model and IQQM, a streamflow routing tool, as well as various global climate model outputs from which daily rainfall and potential evaporation data files have been generated in OzClim, a climate scenario generator. For a 10% increase in tree cover in the headwaters of the Macquarie, we estimate a 17% reduction in inflows to Burrendong Dam. The drying trend for a mid-range scenario of regional rainfall and potential evaporation caused by a global warming of 0.5 degree C may cause an additional 5% reduction in 2030. These flow reductions will decrease the frequency of bird-breeding events in Macquarie Marshes (a RAMSAR protected wetland) and reduce the security of supply to irrigation areas downstream. Inter-decadal climate variability is predicted to have a very significant influence on catchment hydrologic behaviour. A further 20% reduction in flows from the long-term historical mean is possible, should we move into an extended period of below average rainfall years, such as occurred in eastern Australia between 1890 and 1948. Because current consumptive water use is largely adapted to the wetter conditions of post 1949, a return to prolonged dry periods would cause significant environmental stress given the agricultural and domestic water developments that have been instituted.

Maleic anhydride, a precursor to polyester resins, is made by oxidation of n-butane over vanadium phosphate catalysts. This system is of general interest because it is the only heterogeneously catalyzed, alkane-selective oxidation reaction in commercial use. Time-resolved in situ x-ray absorption spectroscopy shows that when either alphaI-VOPO4/SiO2 or (VO)2P2O7/SiO2 catalysts are exposed to n-butane, the rate of maleic anhydride formation is proportional to the rate of decay of V5+ species in the catalyst. Thus V5+ species are kinetically significant for the production of maleic anhydride and not just for the production of by-products. The results also suggest that V5+ species may play a role in the initial hydrogen abstraction from n-butane, the rate-determining step in the reaction sequence. V4+ sites appear to be responsible for by-product formation.

The successful development of digital radiography depends, to a large extent, on the availability of suitable x-ray photoconductors. The x-ray photoconductive nanocomposites reported here combine the advantages of both inorganic and organic compounds. An inorganic compound was finely dispersed in an organic polymer. The inorganic compound, with its large x-ray absorption efficiency, functioned as the x-ray absorber, and the polymer provided good dielectric properties and ease of thin-film preparation. The preparation procedures and the x-ray photoconductive properties of a specific example, a 50 percent by weight nanocomposite of bismuth triiodide and nylon-11, are discussed in detail.

A comprehensive screening and confirmatory method was developed for monitoring polychlorinated biphenyls (PCBs), both as Aroclors and as individual congeners. This approach incorporates extraction, extract cleanup, and analysis modules designed to match cost, time, and data quality requirements. Soxhlet, sonication, supercritical fluid, and accelerated solvent extractions were evaluated. Carbon chromatographic cleanup procedures were used for separation of congeners on the basis of ortho substitutions, which permitted calculation of toxicity equivalents. Individual congener determinations, congener total histograms, and peak comparison techniques for Aroclor identification were elaborated by using high and low resolution mass spectrometric data. A screening procedure based on immunoassay using the Ohmicron PCB RaPID Assay kit gave results comparable to those obtained by gas chromatography with electron capture detection in the range 0.40-230 ppm, when the appropriate Aroclor calibrator was used.

Gas chromatography-mass spectrometry data from the analysis of complex environmental samples were converted into ASCII text and imported into a personal computer spreadsheet. A macro was written to perform mass spectral enhancement by statistical and mathematical procedures to separate the spectra of compounds of interest from interfering mass spectral responses, such as those of broadly eluting hydrocarbons. The extracted mass spectra were compared to reference spectra, with the result that usually 80-90% of the ions common to those in the reference spectra were successfully extracted by using this method. This procedure improved mass spectral quality and the ability of the data system to perform successful library searches. The fitted quality parameters showed systematic improvements after the data were subjected to the spectral enhancement procedures. These procedures could help to identify unknowns by separating their spectra from other signals, such as those of background aliphatic hydrocarbons.

Prolonged and severe trauma, particularly trauma that occurs early in the life cycle, tends to result in a chronic inability to modulate emotions. When this occurs, people can mobilize a range of behaviors that are best understood as attempts at self-soothing. Some of these attempts include clinging and indiscriminate relationships with others in which old traumas are re-enacted over time, as well as more self-directed behaviors such as self-mutilation, eating disorders, and substance abuse. Usually, these behaviors will coexist. Patients with complicated trauma histories often repetitively attempt suicide or engage in chronic self-destructive behavior, and need to address issues of childhood trauma, neglect, and abandonment, both in the past and as re-experienced in current relationships. When treating these patients, therapists must anticipate that painful affects related to interpersonal safety, anger, and emotional needs may give rise to dissociative episodes, which may, in turn, be accompanied by increased self-destructive behavior. The therapy must clarify how current stresses are experienced as a return of past traumas and how small disruptions in present relationships are seen as a repetition of prior abandonment. As part of this, it is essential that the therapist provide validation and support, and avoid participating in a re-enactment of the trauma. Fear needs to be tamed in order for people to be able to think and be conscious of current needs. This bodily response of fear can be mitigated by safety of attachments, security of meaning schemes, and by a body whose reactions to environmental stress can be predicted and controlled. One of the great mysteries of the processing of traumatic experience is that as long as the trauma is experienced as speechless terror, the body continues to keep score and react to conditioned stimuli as a return of the trauma. When the mind is able to create symbolic representations of these past experiences, however, there often seems to be a taming of terror, a desomatization of experience. As Ducey and van der Kolk found in the Rorschachs of Vietnam veterans, patients were unresponsive to outside influences (good or bad) as long as they remained in a state of psychic numbing. Faced with intrusions of past trauma in their current emotional life, patients' initial sense of being overwhelmed was mastered only when a link between past trauma and current perceptions became understood.(ABSTRACT TRUNCATED AT 400 WORDS)

The accidental separation of PTSD and the dissociative disorders, based on the unfortunate fact that the PTSD and the dissociative disorder workgroups of the DSM-III never met to compare data, and the lack of knowledge within the workgroups of existing research connecting these disorders, will continue in the DSM-IV. That separation, however, is slowly being eroded by a solid body of research that shows that these conditions rarely occur independently. Thus, contemporary research is beginning to show that the original concept of "hysteria," formulated 150 years ago to capture a group of patients who have complex psychological and somatic problems and whose problems often elude intervention from the medical and psychological professions, is alive and well among patients on the verge of the twenty-first century. Although the DSM process has attempted to create cleaner diagnostic categories, 100 years of research on traumatized patients consistently shows that these patients defy easy classification, and that they seem to have symptoms that represent somatic, social, symbolic, and intrapsychic adaptations to having experienced overwhelming terror. Thus, what the DSM split when it abolished hysteria as a diagnosis, has once again been found to constitute a syndrome, a conglomeration of symptoms, first defined by Briquet and Janet more than 100 years ago, which is the result of severe and prolonged interpersonal abuse, usually starting in childhood. One hundred years of research has shown us that patients often cannot remember and, instead, re-enact their dramas. The professions ministering to these patients have had similar problems with remembering the past, and thrice in this century have forgotten the hard-earned lessons from our patients. It is not likely that these amnesias and dissociations will be a thing of the past; they are likely to continue as long as physicians and psychologists are faced, helplessly, with man's inhumanity to man.