781 research outputs found

    The relationship between second-generation antipsychotic medication adherence and negative symptoms in first-episode schizophrenia

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    Adherence to psychotropic medication is a critical aspect of treatment for the management of psychotic disorders. While the literature on the need for medication adherence is extensive, little research has explored the relationship between the negative symptoms of psychosis and medication adherence. Since negative symptoms are enduring, stable, and strongly correlated with poor outcome, it is vitally important for research to explore the role of negative symptoms in regards to adherence to psychotropic medication. Given its potentially significant consequences for treatment interventions, the purpose of this study was to contribute to the exceedingly limited body of research exploring the relationship between the negative symptoms seen in psychosis and medication adherence. This study examined if there is a relationship between the two and whether causality could be determined should a significant relationship exist between medication adherence and negative symptoms. This study utilized data previously collected at the UCLA Aftercare Research Program for studies examining aspects of outpatient psychiatric treatment. The 148 participants had a mean age of 22.5 years and were in the midst of their first psychotic episode upon study entry. Data from the Brief Psychiatric Rating Scale, Scale for the Assessment of Negative Symptoms, and medication adherence ratings were collected over the course of 12 months. Analyses revealed a significant relationship between the presence of negative symptoms and medication nonadherence. Analyses examining the temporal relationship between the two variables revealed that initial medication nonadherence was significantly associated with subsequent negative symptoms. However, once the impact of positive symptoms was controlled for as a potential mediating variable, the strength of the relationship between medication adherence and negative symptoms dissipated. After controlling for the role of reality distortion, the only negative symptoms significantly associated with medication nonadherence were the BPRS Negative Symptom Factor, BPRS Emotional Withdrawal, and BPRS Self-Neglect. Consequently, it appears that negative symptoms are more strongly associated with positive symptoms than with medication adherence. Replication of these findings and further research exploring the relationship between positive and negative symptoms as they relate to medication adherence is needed in order to improve treatment interventions focused on medication adherence

    Annual Survey of Virginia Law: Environmental Law

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    This article addresses significant developments in Virginia law pertaining to air quality, water quality and solid and hazardous waste which have occurred between the publication of the 1990 survey and May 1, 1992

    Influence of Fires, Fungi and Mountain Pine Beetles on Development of a Lodgepole Pine Forest in South-Central Oregon

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    Virtually pure lodgepole pine stands form an edaphic climax community over large areas of the infertile pumice plateau of south-central Oregon. During our ongoing studies on the dynamics of these forest we developed the scenario that periodic fires create fungal infection courts in damaged roots; in time, advanced decay develops in the butts and stems of these trees. The mountain pine beetle preferentially selects and kills these trees during the flight season. As these outbreaks develop, additional uninfected trees are attacked. In time, the stage is set for subsequent fires as needles drop, snags fall, and logs decay

    Northwest Africa 8535 and Northwest Africa 10463: New Insights into the Angrite Parent Body

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    The angrite meteorites are valuable samples of igneous rocks formed early in Solar System history (approx.4.56 Ga, summarized in [1]). This small meteorite group (approx.24 individually named specimens) consists of rocks with somewhat exotic mineral compositions (e.g., high Ca olivine, Al-Ti-bearing diopside-hedenbergite, calcium silico-phosphates), resulting in exotic bulk rock compositions. These mineral assemblages remain fairly consistent among angrite samples, which suggests they formed due to similar processes from a single mantle source. There is still debate over the formation process for these rocks (see summary in [1]), and analysis of additional angrite samples may help to address this debate. Toward this end, we have begun to study two new angrites, Northwest Africa 8535, a dunite, and Northwest Africa 10463, a basaltic angrite

    Petrogenesis of Igneous-Textured Clasts in Martian Meteorite Northwest Africa 7034

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    The martian meteorite Northwest Africa 7034 (and pairings) is a breccia that samples a variety of materials from the martian crust. Several previous studies have identified multiple types of igneous-textured clasts within the breccia [1-3], and these clasts have the potential to provide insight into the igneous evolution of Mars. One challenge presented by studying these small rock fragments is the lack of field context for this breccia (i.e., where on Mars it formed), so we do not know how many sources these small rock fragments are derived from or the exact formation his-tory of these sources (i.e., are the sources mantle de-rived melt or melts contaminated by a meteorite impactor on Mars). Our goal in this study is to examine specific igneous-textured clast groups to determine if they are petrogenetically related (i.e., from the same igneous source) and determine more information about their formation history, then use them to derive new insights about the igneous history of Mars. We will focus on the basalt clasts, FTP clasts (named due to their high concentration of iron, titanium, and phosphorous), and mineral fragments described by [1] (Fig. 1). We will examine these materials for evidence of impactor contamination (as proposed for some materials by [2]) or mantle melt derivation. We will also test the petrogenetic models proposed in [1], which are igneous processes that could have occurred regardless of where the melt parental to the clasts was formed. These models include 1) derivation of the FTP clasts from a basalt clast melt through silicate liquid immiscibility (SLI), 2) derivation of the FTP clasts from a basalt clast melt through fractional crystallization, and 3) a lack of petrogenetic relationship between these clast groups. The relationship between the clast groups and the mineral fragments will also be explored

    A TEM Investigation of the Fine-Grained Matrix of the Martian Basaltic Breccia NWA 7034

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    The martian basaltic breccia NWA 7034 is characterized by fine-grained groundmass containing several different types of mineral grains and lithologic clasts. The matrix composition closely resembles Martian crustal rock and soil composition measured by recent rover and orbiter missions. The first results of NWA 7034 suggest that the brecciation of this martian meteorite may have formed due to eruptive volcanic processes; however, impact related brecciation processes have been proposed for paired meteorites NWA 7533 and NWA 7475]. Due to the very fine grain size of matrix, its textural details are difficult to resolve by optical and microprobe observations. In order to examine the potential nature of brecciation, transmission electron microscopy (TEM) studies combined with focused ion-beam technique (FIB) has been undertaken. Here we present the preliminary observations of fine-grained groundmass of NWA 7034 from different matrix areas by describing its textural and mineralogical variations and micro-structural characteristics

    Feldspar Variability in Northwest Africa 7034

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    The martian meteorite Northwest Africa 7034 (and pairings) is a breccia that provides important information about the rocks and processes of the martian crust (e.g., 1-3). Additional information can be gleaned from the components of the breccia. These components, specifically those designated as clasts, record the history of their parent rock (i.e., the rock that has been physically broken down to produce the clasts). In order to study these parent rocks, we must first determine which clasts within the breccia are de-rived from the same parent. Previous studies have be-gun this process (e.g., 4), but the search for genetic linkages between clasts has not integrated clasts with different grain sizes. We begin to take this approach here, incorporating igneous-textured clasts with both fine and coarse mineral grains. In NWA 7034, almost all materials (clasts and breccia matrix) are composed of the same mineral assemblages (feldspar, pyroxene, Fe-Ti oxides, apatite) with largely the same mineral compositions [1, 4-6]. Bulk breccia Sm-Nd systematics define a single isochron [7]. These observations are consistent with a majority of the components within NWA 7034 originating from the same geochemical source and crystallizing at roughly the same time

    Hydrogen Isotopic Composition of Apatite in Northwest Africa 7034: A Record of the "Intermediate" H-Isotopic Reservoir in the Martian Crust?

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    Northwest Africa (NWA) 7034 and its pairings comprise a regolith breccia with a basaltic bulk composition [1] that yields a better match than any other martian meteorite to visible-infrared reflectance spectra of the martian surface measured from orbit [2]. The composition of the fine-grained matrix within NWA 7034 bears a striking resemblance to the major element composition estimated for the martian crust, with several exceptions. The NWA 7034 matrix is depleted in Fe, Ti, and Cr and enriched in Al, Na, and P [3]. The differences in Al and Fe are the most substantial, but the Fe content of NWA 7034 matrix falls within the range reported for the southern highlands crust [6]. It was previously suggested by [4] that NWA 7034 was sourced from the southern highlands based on the ancient 4.4 Ga ages recorded in NWA 7034/7533 zircons [4, 5]. In addition, the NWA 7034 matrix material is enriched in incompatible trace elements by a factor of 1.2-1.5 [7] relative to estimates of the bulk martian crust. The La/Yb ratio of the bulk martian crust is estimated to be approximately 3 [7], and the La/Yb of the NWA 7034 matrix materials ranges from approximately 3.9 to 4.4 [3, 8], indicating a higher degree of LREE enrichment in the NWA 7034 matrix materials. This elevated La/Yb ratio and enrichment in incompatible lithophile trace elements is consistent with NWA 7034 representing a more geochemically enriched crustal terrain than is represented by the bulk martian crust, which would be expected if NWA 7034 represents the bulk crust from the southern highlands. Given the similarities between NWA 7034 and the martian crust, NWA 7034 may represent an important sample for constraining the composition of the martian crust, particularly the ancient highlands. In the present study, we seek to constrain the H isotopic composition of the martian crust using Cl-rich apatite in NWA 7034. Usui et al., [9] recently proposed that a H isotopic reservoir exists within the martian crust that has a H-isotopic composition that is intermediate (D of 1000-2000per mille) between an isotopically light mantle (Delta D is less than 275per mille [10]) and an isotopically heavy atmosphere (D of 2500-6100per mille [11, 12]). Apatites in NWA 7034 occur in a number of lithologic domains, however apatites across all lithologic domains have been affected by a Pb-loss event at about 1.5 Ga before present [5], so they are unlikely to have retained a primary composition and are more likely to have equilibrated with fluids within the martian crust that may or may not have exchanged with the martian atmosphere. Equilibration of apatite with crustal fluids is further supported by the chlorine-rich compositions exhibited by apatites in NWA 7034 in comparison to apatites from other martian meteorites (Figure 1; [13]). Cl is more hydrophilic than F, which promotes formation of Cl-rich apatite compositions in fluid-rich systems [e.g., 14, 15-17]

    H-Isotopic Composition of Apatite in Northwest Africa 7034

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    Northwest Africa (NWA) 7034 and its pairings comprise a regolith breccia with a basaltic bulk composition [1] that yields a better match than any other martian meteorite to estimates of Mars' bulk crust composition [1]. Given the similarities between NWA 7034 and the martian crust, NWA 7034 may represent an important sample for constraining the crustal composition of components that cannot be measured directly by remote sensing. In the present study, we seek to constrain the H isotopic composition of the martian crust using Cl-rich apatite in NWA 7034

    Statistical analysis of wind speed and wind power potential of Port Elizabeth using Weibull parameters

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    This paper analyses wind speed characteristics and wind power potential of Port Elizabeth using statistical Weibull parameters. A measured 5–minute time series average wind speed over a period of 5 years (2005 - 2009) was obtained from the South African Weather Service (SAWS). The results show that the shape parameter (k) ranges from 1.319 in April 2006 to 2.107 in November 2009, while the scale parameter (c) varies from 3.983m/s in May 2008 to 7.390 in November 2009.The average wind power density is highest during Spring (September–October), 256.505W/m2 and lowest during Autumn (April-May), 152.381W/m2. This paper is relevant to a decision-making process on significant investment in a wind power project
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