1,113 research outputs found
Sexual Orientation Belief Profiles, Attitudes, and Identity Development: A Person-Centered Analysis
In the current study, we integrated the following largely disparate literatures: (a) sexual identity development and developmental milestones; (b) beliefs about sexual orientation; and (c) attitudes regarding sexual identity. We recruited a sample of sexual minority participants (n = 416) via Amazon Mechanical Turk (MTurk) who recalled the age of completing sexual identity developmental milestones (Calzo et al., 2011) and completed the Sexual Orientation Beliefs Scale (SOBS; Arseneau et al., 2013), the Lesbian, Gay, Bisexual Identity Scale (LGBIS; Mohr & Kendra, 2011), and the Kessler Psychological Distress Scale (KPDS; Kessler et al., 2002). We conducted a latent profile analysis (LPA) on the SOBS and replicated previous findings of three distinct belief profiles that were high in discreteness, entitativity, and importance beliefs (a group we named high-DEI), high only with regards to naturalness beliefs (i.e., naturalness-only), and relatively high levels of beliefs across all four types of sexual orientation beliefs (i.e., multidimensional essentialism). Sexual orientation predicted participantsâ profile membership, with gay and lesbian participants being more likely to endorse beliefs consistent with the naturalness-only group. Sexual minority people of color were more likely to have response patterns consistent with the high-DEI profile than any other profile. Those recalling first same-sex attraction later in life were more likely to endorse sexual orientation beliefs consistent with the multidimensional essentialism and high-DEI profiles than the naturalness-only profile. Members of the high-DEI profile endorsed the highest levels of all positive and negative attitudes regarding sexual orientation as measured by the LGBIS and endorsed significantly higher levels of psychological distress than members of both the multidimensional essentialism and naturalness-only profiles. The implications of these findings are discussed
SNARE VTI13 plays a unique role in endosomal trafficking pathways associated with the vacuole and is essential for cell wall organization and root hair growth in arabidopsis
Background and Aims: Root hairs are responsible for water and nutrient uptake from the soil and their growth is responsive to biotic and abiotic changes in their environment. Root hair expansion is a polarized process requiring secretory and endosomal pathways that deliver and recycle plasma membrane and cell wall material to the growing root hair tip. In this paper, the role of VTI13 (AT3G29100), a member of the VTI vesicular soluble NSF attachment receptor (SNARE) gene family in Arabidopsis thaliana, in root hair growth is described.<p></p>
Methods: Genetic analysis and complementation of the vti13 root hair phenotypes of Arabidopsis thaliana were first used to assess the role of VTI13 in root hair growth. Transgenic lines expressing a green fluorescent protein (GFP)âVTI13 construct were used to characterize the intracellular localization of VTI13 in root hairs using confocal microscopy and immunotransmission electron microscopy.<p></p>
Key Results: VTI13 was characterized and genetic analysis used to show that its function is required for root hair growth. Expression of a GFPâVTI13 fusion in the vti13 mutant background was shown to complement the vti13 root hair phenotype. GFPâVTI13 localized to both the vacuole membrane and a mobile endosomal compartment. The function of VTI13 was also required for the localization of SYP41 to the trans-Golgi network. Immunohistochemical analysis indicated that cell wall organization is altered in vti13 root hairs and root epidermal cells.<p></p>
Conclusions: These results show that VTI13 plays a unique role in endosomal trafficking pathways associated with the vacuole within root hairs and is essential for the maintenance of cell wall organization and root hair growth in arabidopsis
Learning from Other Communities
This paper reflects a synopsis of the work in person/family-centered planning representative of its implementation across a variety of disability service systems, including prisons, schools, community-based service agencies and institutional settings. The authors who have contributed to this paper have direct experience in the field working with individuals who have disability labels of severe and persistent mental illness, mental retardation and developmental disabilities, and learning disabilities. It is their hope that this paper will serve to guide the emerging best practice in the design and delivery of person-centered service delivery systems
Using monoclonal antibodies to label living root hairs: a novel tool for studying cell wall microarchitecture and dynamics in <i>Arabidopsis</i>
Background<p></p>
The Arabidopsis root hair represents a valuable cell model for elucidating polar expansion mechanisms in plant cells and the overall biology of roots. The deposition and development of the cell wall is central to the root hair expansion apparatus. During this process, incorporation of specific wall polymers into the growing wall architecture constitutes a critical spatio-temporal event that controls hair size and growth rate and one that is closely coordinated with the cellâs endomembrane, cytoskeletal and signal transduction apparatuses.<p></p>
Results<p></p>
In this study, the protocol for live cell labeling of roots with monoclonal antibodies that bind to specific wall polymers is presented. This method allows for rapid assessment of root hair cell wall composition during development and assists in describing changes to cell wall composition in transgenic mutant lines. Enzymatic âunmaskingâ of specific polymers prior to labeling allows for refined interpretation of cell wall chemistry. Live cell immunofluorescence data may also be correlated with transmission electron microscopy-based immunogold labeling.<p></p>
Conclusions<p></p>
Live Arabidopsis root hairs may be labeled with cell wall polymer-specific antibodies. This methodology allows for direct visualization of cell wall dynamics throughout development in stable transgenic plant lines. It also provides an important new tool in the elucidation of the specific interactions occurring between membrane trafficking networks, cytoskeleton and the cell wall deposition/remodeling mechanism
Motion of the Zinc Ions in Catalysis by a Dizinc Metallo-β-Lactamase
We report rapid-freeze-quench X-ray absorption spectroscopy of a dizinc metallo-β-lactamase (MβL) reaction intermediate. The Zn(II) ions in the dinuclear active site of the S. maltophilia Class B3 MβL move away from each other, by âź0.3 Ă
after 10 ms of reaction with nitrocefin, from 3.4 to 3.7 Ă
. Together with our previous characterization of the resting enzyme and its nitrocefin product complex, where the Zn(II) ion separation relaxes to 3.6 Ă
, these data indicate a scissoring motion of the active site that accompanies the ring-opening step. The average Zn(II) coordination number of 4.5 in the resting enzyme appears to be maintained throughout the reaction with nitrocefin. This is the first direct structural information available on early stage dizinc metallo-β-lactamase catalysis
General Intelligence and Modality-specific Differences in Performance: A Response to Schellenberg (2008)
Tierney et al. (2008) reported that musicians performed better on an
auditory sequence memory task when compared to non-musicians, but the two
groups did not differ in performance on a sequential visuo-spatial memory task.
Schellenberg (2008) claims that these results can be attributed entirely to
differences in IQ. This explanation, however, cannot account for the fact that the
musiciansâ advantage was modality-specific
A Five-coordinate Metal Center in Co(II)-substituted VanX
In an effort to structurally probe the metal binding site in VanX, electronic absorption, EPR, and extended x-ray absorption fine structure (EXAFS) spectroscopic studies were conducted on Co(II)-substituted VanX. Electronic spectroscopy revealed the presence of Co(II) ligand field transitions that had molar absorptivities of âź100 mâ1 cmâ1, which suggests that Co(II) is five-coordinate in Co(II)-substituted VanX. Low temperature EPR spectra of Co(II)-substituted VanX were simulated using spin Hamiltonian parameters of M = |¹½ă, E/D = 0.14, greal(x,y) = 2.37, and grealS(z) = 2.03. These parameters lead to the prediction that Co(II) in the enzyme is five-coordinate and that there may be at least one solvent-derived ligand. Single scattering fits of EXAFS data indicate that the metal ions in both native Zn(II)-containing and Co(II)-substituted VanX have the same coordination number and that the metal ions are coordinated by 5 nitrogen/oxygen ligands at âź 2.0 Ă
. These data demonstrate that Co(II) (and Zn(II) from EXAFS studies) is five-coordinate in VanX in contrast to previous crystallographic studies (Bussiere, D. E., Pratt, S. D., Katz, L., Severin, J. M., Holzman, T., and Park, C. H. (1998) Mol. Cell 2, 75â84). These spectroscopic studies also demonstrate that the metal ion in Co(II)-substituted VanX when complexed with a phosphinate analog of substrate d-Ala-d-Ala is also five-coordinate
Ecosystem uptake and transfer of Sellafield-derived radiocarbon (14C). Part 1. The Irish Sea
Ecosystem uptake and transfer processes of Sellafield-derived radiocarbon (14C) within the Irish Sea were examined. Highly variable activities in sediment, seawater and biota indicate complex 14C dispersal and uptake dynamics. All east basin biota exhibited 14C enrichments above ambient background while most west basin biota had 14C activities close to background, although four organisms including two slow-moving species were significantly enriched. The western Irish Sea gyre is a suggested pathway for transfer of 14C to the west basin and retention therein. Despite ongoing Sellafield 14C discharges, organic sediments near Sellafield were significantly less enriched than associated benthic organisms. Rapid scavenging of labile, 14C-enriched organic material by organisms and mixing to depth of 14C-enriched detritus arriving at the sediment/water interface are proposed mechanisms to explain this. All commercially important fish, crustaceans and molluscs showed 14C enrichments above background; however, the radiation dose from their consumption is extremely low and radiologically insignificant
GMA Instrumentation of the Athena Framework using NetLogger
Grid applications are, by their nature, wide-area distributed applications.
This WAN aspect of Grid applications makes the use of conventional monitoring
and instrumentation tools (such as top, gprof, LSF Monitor, etc) impractical
for verification that the application is running correctly and efficiently. To
be effective, monitoring data must be "end-to-end", meaning that all components
between the Grid application endpoints must be monitored. Instrumented
applications can generate a large amount of monitoring data, so typically the
instrumentation is off by default. For jobs running on a Grid, there needs to
be a general mechanism to remotely activate the instrumentation in running
jobs. The NetLogger Toolkit Activation Service provides this mechanism.
To demonstrate this, we have instrumented the ATLAS Athena Framework with
NetLogger to generate monitoring events. We then use a GMA-based activation
service to control NetLogger's trigger mechanism. The NetLogger trigger
mechanism allows one to easily start, stop, or change the logging level of a
running program by modifying a trigger file. We present here details of the
design of the NetLogger implementation of the GMA-based activation service and
the instrumentation service for Athena. We also describe how this activation
service allows us to non-intrusively collect and visualize the ATLAS Athena
Framework monitoring data
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