One- and two-axis squeezing of atomic ensembles in optical cavities

The strong light-matter coupling attainable in optical cavities enables the generation of highly squeezed states of atomic ensembles. It was shown in [Phys. Rev. A 66, 022314 (2002)] how an effective one-axis twisting Hamiltonian can be realized in a cavity setup. Here, we extend this work and show how an effective two-axis twisting Hamiltonian can be realized in a similar cavity setup. We compare the two schemes in order to characterize their advantages. In the absence of decoherence, the two-axis Hamiltonian leads to more squeezing than the one-axis Hamiltonian. If limited by decoherence from spontaneous emission and cavity decay, we find roughly the same level of squeezing for the two schemes scaling as (NC)^(1/2) where C is the single atom cooperativity and N is the total number of atoms. When compared to an ideal squeezing operation, we find that for specific initial states, a dissipative version of the one-axis scheme attains higher fidelity than the unitary one-axis scheme or the two-axis scheme. However, the unitary one-axis and two-axis schemes perform better for general initial states.Comment: 13 pages, 6 figure

Will They Be Welcomed In? The Impact of K-12 Teachers’ and Principals’ Perceptions of Inclusion of Students with Disabilities

The purpose of this study is to investigate the perceptions K-12 principals and teachers have of inclusive education in a school district in western Pennsylvania school district. The dependent variables are the teachers’ and principals’ perceptions of inclusion and the independent variables are years of educational experience, extent of special education background, and level of support by district administrators. Instrumentation for this study is the Multidimensional Attitudes toward Inclusive Education Scale (MATIES) survey. Data were analyzed for correlational relationships using the Statistical Package for the Social Sciences (SPSS). Findings suggest an average to high level of support by administration in supporting inclusive practices. A statistically significant, small negative relationship between the years teaching and responses on the affective and behavioral factors surfaced. No significant relationship was demonstrated between teachers’ perceptions of inclusion and the level of reported support they receive from administrators

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Links between Anr and Quorum Sensing in Pseudomonas aeruginosa Biofilms

In Pseudomonas aeruginosa, the transcription factor Anr controls the cellular response to low oxygen or anoxia. Anr activity is high in oxygen-limited environments, including biofilms and populations associated with chronic infections, and Anr is necessary for persistence in a model of pulmonary infection. In this study, we characterized the Anr regulon in biofilm-grown cells at 1% oxygen in the laboratory strain PAO1 and in a quorum sensing (QS)-deficient clinical isolate, J215. As expected, transcripts related to denitrification, arginine fermentation, high-affinity cytochrome oxidases, and CupA fimbriae were lower in the Δanr derivatives. In addition, we observed that transcripts associated with quorum sensing regulation, iron acquisition and storage, type VI secretion, and the catabolism of aromatic compounds were also differentially expressed in the Δanr strains. Prior reports have shown that quorum sensing-defective mutants have higher levels of denitrification, and we found that multiple Anr-regulated processes, including denitrification, were strongly inversely proportional to quorum sensing in both transcriptional and protein-based assays. We also found that in LasR-defective strains but not their LasR-intact counterparts, Anr regulated the production of the 4-hydroxy-2-alkylquinolines, which play roles in quorum sensing and interspecies interactions. These data show that Anr was required for the expression of important metabolic pathways in low-oxygen biofilms, and they reveal an expanded and compensatory role for Anr in the regulation of virulence-related genes in quorum sensing mutants, such as those commonly isolated from infections

Considering Positive Psychology Constructs of Life Satisfaction and School Connectedness When Assessing Symptoms Related to Attention-Deficit/Hyperactivity Disorder

Children and adolescents diagnosed with Attention-Deficit/Hyperactivity Disorder (ADHD) demonstrate significant difficulty with academic and behavioral functioning. This, in turn, can lead to lower educational attainment and vocational achievement, which has serious long-term consequences and costs to individuals and society (Barkley, 2002, 2006; Mannuzza, Klein, Bessler, Malloy, & LaPadula, 1993). Researchers from a positive psychology framework suggest that ADHD symptoms (i.e., inattention, hyperactivity/impulsivity) alone may not fully explain academic impairment (Diener, Scollon, & Lucas, 2004). From the standpoint of positive psychology, life satisfaction and school connectedness are important constructs that examine positive life functioning; however, they have been understudied, particularly in the area of ADHD. The current study investigated the relationship between ADHD symptoms and these positive psychological constructs. Results indicate that as ADHD symptoms increase, life satisfaction decreases; however, no relationship between ADHD symptoms and school connectedness was found. Beyond our primary analysis, we examined the relationship between gender and these variables. Results suggest that gender significantly moderates the relationship between ADHD and life satisfaction, with life satisfaction ratings decreasing for males as ADHD symptoms increase, yet remaining stable for females. ADHD symptoms did not significantly predict changes in school connectedness

Multiple-Methods Needs Assessment of California 4-H Science Education Programming

The California 4-H Science Leadership Team conducted a statewide assessment to evaluate the needs of county-based 4-H programs related to the key areas of the 4-H Science Initiative: program development and design, professional development, curricula, evaluation, partnerships, and fund development. The use of multiple qualitative data sources proved effective in identifying needs and gaps. Integrated findings provided evidence of institutionalization of 4-H Science; the assessment also revealed gaps that represent opportunities for future efforts and directions. Needs identified included intentional and systematic science programming, effective program models, professional development for staff, and consistency in messaging and branding