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The Lameta Formation (Upper Cretaceous, Maastrichtian) of India has yielded abundant fossils of abelisaurid theropods, including bones from the cranium, vertebral column, pectoral and pelvic girdles, and hindlimb. However, the forelimbs of Indian abelisaurids remain unknown. Here we describe an abelisaurid humerus from exposure of the Lameta Formation near the village of Rahioli in northwestern India. This new material exhibits derived traits that are distinctive of Abelisauridae, for example an articular head that is hemispherical in proximal view, thus establishing the specimen as the first abelisaurid humerus from India.

We study in this note some dynamical properties of $$F(z) = z^2 - 2\bar z$$ ,F:ℂ→ℂ. LetK=K (F) denote the set of all points whose orbit is bounded. We prove thatF restricted to ℂ\K behaves as ψ(z)=z 2 does in the complement of the unit disk;K has positive area;F restricted toK is transitive; the set of periodic points ofF is dense inK and the topological entropy of F/K is positive.

The purpose of this study was to estimate the prevalence of erectile dysfunction (ED) in Colombia, Ecuador, and Venezuela. A 49-item questionnaire was completed by 1946 men aged 40 years and older. The age-adjusted combined prevalence of minimal, moderate, and complete ED for all three countries was 53.4%, with 19.8% of all men reporting moderate to complete ED. Age was the variable most strongly linked to ED; the prevalence of complete ED increased markedly in men older than 79 y of age (31.9%) and 70-79 y (17.2%) compared with men aged 40-49 y (

1 IntroductionPhotochemical processing of materials, particularly insemiconductors, has been a relatively well-known techniqueused for some time with relatively few applications [1].However, devices demanding new processing techniques,suchasMEMS[2],Leds[3]andlaserswithintegratedlensesor gratings, etc. have renewed interest in this technique.The technique can be described as follows [4]: a semi-conductor is immersed in an electrolyte, forming a spacecharge region at the solution–semiconductor interface; at thesame time the semiconductor is illuminated with light (nor-mally a laser) of energy greater than the material’s band gap,creating electron-hole pairs. The electric field due to bandbending at the semiconductor surface attracts one type ofcarrier to the surface and repels the other type of carriertowardsthebulk.Normally,inn-typematerial,theholesgotothesurfaceandtheelectronstothebulk.Inthiscasetheexcessholes increase the oxidation state of the surface atoms,increasingtheetchingrate.Ifthereactionrateislimitedbythesupplyofphoto-generatedholesatthesurface,theetchingratecan be adjusted simply by changing the light intensity.Since the technique uses a beam of monochromaticphotons (laser) to locally control reactive interactions nearthe solid surface, it is particularly useful to performlocalized material deposition (writing), solid doping,alloying and/or, as in our case, material removing (etching)without masking assistance [5]. Due to these unique char-acteristics Laser-Assisted Chemical Etching (LACE) offersadvantageous distinctiveness that makes it preferred toother materials processing techniques [6].Of particular interest in this work is the photochemicaletching of semiconductors, also called LACE. This techniquehas been already used successfully to produce channels withapproximately parabolic cross section along GaAs substrates,creating a refraction index negative gradient inside a Graded-Index Separate Confinement Heterostructure (GRIN-SCH)laser structure. This effect was used to deviate the higher orderlateral modes out of the laser str ucture keeping only the centralone[7].Inthatworkthefeasibilityofanewtypeofhigh-powercoherent semiconductor laser with lateral emission was dem-onstrated. As far as we know this was the first time LACE wasused successfully to build structures in laser diodes thatsimultaneously improved their power output and coherence.In this work we show the results of applying LACE ton-type GaSb substrates to create cavities with nearly par-abolic cross sectioned profiles that could be used as micromirrors or micro lenses to concentrate or deviate lightbeams emitted from a surface emitting laser diode. Aparabolic profile of the mirror is best suited to obtain singlemode operation in an unstable resonator [8, 9].GaSb is an interesting material for the production oflasers and photodetectors in the near and mid infraredregion. However, the use of GaSb requires the developmentof some processing techniques such as etching andpolishing. Chemical processing of GaSb is particularly

A Metal / Organic / Inorganic semiconductor heterostructure was built and characterized in situ under ultra-high vacuum conditions (UHV). The aim was to investigate the influence of a perylene-derivative organic thin film on the transport electronic properties of Schottky Ag / GaAs diodes. The device was studied using a combination of photoemission spectroscopy (PES) and electrical measurements. The obtained results were discussed using the analytical expressions of a trapped charge limited current (TCLC) model.

Erratum to: Pala¨ontol ZDOI 10.1007/s12542-010-0055-zOwing to an unfortunate oversight, the legend to Fig. 1does not indicate that the figure was modified from Wilsonet al. (2003):Wilson, J.A., P.C. Sereno, S. Srivastava, D.K. Bhatt,A. Khosla, and A. Sahni. 2003. A new abelisaurid(Dinosauria, Theropoda) from the Lameta Formation(Cretaceous, Maastrichtian) of India. Contributions fromthe Museum of Paleontology, University of Michigan31: 1–42.The authors apologize for this omission.