The chicken mite.

According to tho twelfth census, Iowa led the states of the union in the number of chickens three months old and over, having June 1, 1900, 18,907,673. The value of poultry raised in 1899 was $9,491,818.00 and the value of eggs produced during that time$10,016,707.00. Allowing for the necessary incorrectness of such statistics it is still certain that we have in this state a vast poultry industry whose interests are deserving of our closest attention. The mite attacks other species of domestic fowls besides the chicken, also at times becomes a serious pest to horses stabled with fowls or near them and even becomes parasitic upon man. This bulletin, however, deals only with the mite as it affects chickens, but the principles which it sets forth can be applied equally well in all conditions under which the mite exists

A systematic search for lensed high-redshift galaxies in HST images of MACS clusters

International audienceWe present the results of a 135-arcmin 2 search for high-redshift galaxies lensed by 29 clusters from the MAssive Cluster and extended MAssive Cluster Surveys. We use relatively shallow images obtained with the Hubble Space Telescope in four passbands, namely, F606W, F814W, F110W, and F140W. We identify 130 F814W dropouts as candidates for galaxies at z 6. In order to fit the available broad-band photometry to galaxy spectral energy distribution (SED) templates, we develop a prior for the level of dust extinction at various redshifts. We also investigate the systematic biases incurred by the use of SED-fit software. The fits we obtain yield an estimate of 20 Lyman-break galaxies with photometric redshifts from z ∼ 7 to 9. In addition, our survey has identified over 100 candidates with a significant probability of being lower redshift (z ∼ 2) interlopers. We conclude that even as few as four broad-band filters – when combined with fitting the SEDs – are capable of isolating promising objects. Such surveys thus allow one both to probe the bright end (M 1500 −19) of the high-redshift ultraviolet luminosity function and to identify candidate massive evolved galaxies at lower redshifts

Snell's law for surface electrons: Refraction of an electron gas imaged in real space

On NaCl(100)/Cu(111) an interface state band is observed that descends from the surface-state band of the clean copper surface. This band exhibits a Moire-pattern-induced one-dimensional band gap, which is accompanied by strong standing-wave patterns, as revealed in low-temperature scanning tunneling microscopy images. At NaCl island step edges, one can directly see the refraction of these standing waves, which obey Snell's refraction law.Comment: 4 pages, 4 figure

Scanning tunneling microscopy and spectroscopy of sodium-chloride overlayers on the stepped Cu(311) surface: Experimental and theoretical study

The physical properties of ultrathin NaCl overlayers on the stepped Cu(311) surface have been characterized using scanning tunneling microscopy (STM) and spectroscopy, and density functional calculations. Simulations of STM images and differential conductance spectrum were based on the Tersoff-Hamann approximation for tunneling with corrections for the modified tunneling barrier at larger voltages and calculated Kohn-Sham states. Characteristic features observed in the STM images can be directly related to calculated electronic and geometric properties of the overlayers. The measured apparent barrier heights for the mono-, bi-, and trilayers of NaCl and the corresponding adsorption-induced changes in the work function, as obtained from the distance dependence of the tunneling current, are well reproduced by and understood from the calculated results. The measurements revealed a large reduction of the tunneling conductance in a wide voltage region, resembling a band gap. However, the simulated spectrum showed that only the onset at positive sample voltages may be viewed as a valence band edge, whereas the onset at negative voltages is caused by the drastic effect of the electric field from the tip on the tunneling barrier

Influence of a Feshbach resonance on the photoassociation of LiCs

We analyse the formation of ultracold 7Li133Cs molecules in the rovibrational ground state through photoassociation into the B1Pi state, which has recently been reported [J. Deiglmayr et al., Phys. Rev. Lett. 101, 133004 (2008)]. Absolute rate constants for photoassociation at large detunings from the atomic asymptote are determined and are found to be surprisingly large. The photoassociation process is modeled using a full coupled-channel calculation for the continuum state, taking all relevant hyperfine states into account. The enhancement of the photoassociation rate is found to be caused by an `echo' of the triplet component in the singlet component of the scattering wave function at the inner turning point of the lowest triplet a3Sigma+ potential. This perturbation can be ascribed to the existence of a broad Feshbach resonance at low scattering energies. Our results elucidate the important role of couplings in the scattering wave function for the formation of deeply bound ground state molecules via photoassociation.Comment: Added Erratum, 20 pages, 9 figure

Exploring agency and self-other processing: an FMRI study of dynamic cooperation using an adaptively paced finger tapping task with variable auditory feedback

Ensemble musicians must be flexible and learn to adapt their performance to that of their partners and do so appropriately based on available sensory information streams. To further describe this type of dynamic joint action, we present a functional MRI study of sensorimotor synchronization with an adaptive “virtual partner” (VP). In particular, we investigate the behavioural and neural effects of variable auditory feedback (off, different to or same as pacing tones) associated with finger tapping performance across varying degrees of VP adaptivity (α). We predict that auditory feedback will bias the system to either i) integrate or ii) segregate information regarding “self” or the VP (“other”). We acquired subjective ratings of sense of oneness (self-other merging) and influence (self-other distinction) which we expected to vary with the availability and reliability (ambiguous-same vs. distinct-different) of pertinent auditory information. Behavioural data show a significant interaction effect of auditory feedback on α and synchronization such that distinctive self-other auditory information results in improvements in synchronization, especially at higher levels of α. Furthermore, auditory feedback was seen to have a significant effect on perceived oneness. Specifically, improved synchronization correlates with both ratings of oneness and activation of the precuneus and posterior cingulate, areas thought to integrate external and self generated information. By contrast, a comparison of neural activation in different and same auditory conditions reveals SMA and cerebellum activity. Identification of these structures may be related to greater sensitivity to prediction error as well as self-other distinction necessary for agency processing