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We numerically study a method to increase the photon return flux of continuous-wave laser guide stars using one-dimensional atomic cooling principles. The method relies on chirping the laser towards higher frequencies following the change in velocity of sodium atoms due to recoil, which raises atomic populations available for laser excitation within the Doppler distribution. The efficiency of this effect grows with the average number of atomic excitations between two atomic collisions in the mesosphere. We find the parameters for maximizing the return flux and evaluate the performance of chirping for operation at La Palma. According to our simulations, the optimal chirp rate lies between $ 0.8 {{-}} 1.0 \;{\rm MHz}/\unicode{x00B5} {\rm s} $0.8−1.0MHz/µs, and an increase in the fluorescence of the sodium guide star up to 60% can be achieved with current 20-W-class guide star lasers.

Peer review of teaching is recognized increasingly as one strategy for academic development even though historically peer review of teaching is often unsupported by policy, action and culture in many Australian universities. Higher education leaders report that academics generally do not engage with peer review of teaching in a systematic or constructive manner, and this paper advances and analyses a conceptual model to highlight conditions and strategies necessary for the implementation of sustainable peer review in higher education institutions. The model highlights leadership, development and implementation, which are critical to the success and formation of a culture of peer review of teaching. The work arises from collaborative research funded by the Office for Learning and Teaching to foster and advance a culture of peer review of teaching across several universities in Australia.

Mullerian remnant cysts, also referred to as cutaneous ciliated cysts, are rare skin lesions most commonly found in young females on their lower extremities but can also be found in other locations. The pathogenesis of these lesions is important for understanding their significance and there is a paucity of literature on the clinical course and management of these rare and typically benign masses in young patients. We report a case of a 2 cm Mullerian remnant cyst on the lateral buttock in an 11-year-old female with a prior ovarian cystectomy. The current literature regarding the complex origin and clinical management of these unusual cutaneous lesions is reviewed.

ABSTRACTThe 34-kDa protein encoded by the I3 gene of vaccinia virus is expressed at early and intermediate times postinfection and is phosphorylated on serine residues. Recombinant I3 has been expressed inEscherichia coliand purified to near homogeneity, as has the protein from infected cells. Both recombinant and endogenous I3 protein demonstrate a striking affinity for single-stranded, but not for double-stranded, DNA. The interaction with DNA is resistant to salt, exhibits low cooperativity, and appears to involve a binding site of approximately 10 nucleotides. Electrophoretic mobility shift assays indicate that numerous I3 molecules can bind to a template, reflecting the stoichiometric interaction of I3 with DNA. Sequence analysis reveals that a pattern of aromatic and charged amino acids common to many replicative single-stranded DNA binding proteins (SSBs) is conserved in I3. The inability to isolate viable virus containing an interrupted I3 allele provides strong evidence that the I3 protein plays an essential role in the viral life cycle. A likely role for I3 as an SSB involved in DNA replication and/or repair is discussed.

Para explicar el uso del lenguaje en pacientes esquizofrénicos agudos (es decir, de corta duración) se presentan cinco hipótesis. Estas se basan en los análisis lingüísticos y psicolingüísticos de oyentes (35 de los cuales eran esquizofrénicos, y otros 53 voluntarios normales) y hablantes (40 eran pacientes esquizofrénicos, la mitad de los cuales mostraban signos clínicos de desorden del pensamiento y la otra mitad no, y 20 voluntarios normales). Las muestras de los hablantes fueron tomadas de entrevistas no estructuradas, de descripciones estructuradas, y de narraciones. Se sugiere que los fallos del discurso de los esquizofrénicos agudos se deben a un fallo para cambiar la atención lo bastante rápido como para beneficiarse de la memoria del trabajo.

Schizophrenic (N55) and normal (N53) subjects were presented with sentences and series of random digits. Each test sentence and number series contained a dichotically presented click, and the subject was to locate the click with regard to the test string. In one experiment, sentence and number strings were alternated; in a second experiment, the different strings were recorded in blocks. Results showed that the predictive association of correct localizations in number series with correct localizations in sentences was from 2 to 6 times greater for the schizophrenic listener than for the normal subject. This suggests that limitations in sensory (i.e., nonsyntactic) information processing are an important factor in the schizophrenic’s impaired sentence decoding.

Studies of filled and silent pauses performed in the last two decades are reviewed in order to determine the significance of pauses for the speaker. Following a brief history, the theoretical implications of pause location are examined and the relevant studies summarized. In addition, the functional significance of pauses is considered in terms of cognitive, affective-state, and social interaction variables.

Lambs of different ages treated with cod liver oil developed muscular necrosis and showed an increase in levels of glutamic oxaloacetic transaminase in the serum. In the course of the experiments both treated and control lambs showed a general decline but no differences in serum vitamin E concentrations. Cod liver oil administration also did not affect the concentration of vitamin E in liver, kidney and adrenals and produced no significant change in the thiobarbituric acid values and in the oxygen consumption of tissue homogenates.

Context. Sodium laser guide stars (LGS) are about to enter a new range of laser powers. Previous theoretical and numerical methods are inadequate for accurate computations of the return flux, hence for the design of the next-generation LGS systems.

Context. Sodium laser guide stars (LGS) are about to enter a new range of laser powers. Previous theoretical and numerical methods are inadequate for accurate computations of the return flux, hence for the design of the next-generation LGS systems.Aims. We numerically optimize the cw (continuous wave) laser format, in particular, the light polarization and spectrum.Methods. Using Bloch equations, we simulate the mesospheric sodium atoms, including Doppler broadening, saturation, collisional relaxation, Larmor precession, and recoil, taking all 24 sodium hyperfine states into account and 100–300 velocity groups.Results. LGS return flux is limited by ”three evils”: Larmor precession due to the geomagnetic field, atomic recoil due to radiation pressure, and transition saturation. We study their impact and show that the return flux can be boosted by repumping (simultaneous excitation of the sodium D2a and D2b lines with 10-20% of the laser power in the latter). Conclusions. We strongly recommend the use of circularly polarized lasers and repumping. As a rule of thumb, the bandwidth of laser radiation in MHz (at each line) should approximately equal the launched laser power in Watts divided by six, assuming a diffraction-limited spot size.