Design automation for integrated circuits

With the ever-increasing complexity of integrated circuits, manual design methods have become intolerably slow and error-prone. The use of computers to automate some or all of the design process is necessary to minimize both design time and error incidence. In this article are discussed the design and fabrication of integrated circuits, selected techniques of design automation, and the problems associated with such automation.     

Persistent Frenulum of the Epiglottis in Four Foals

OBJECTIVE: To report the clinical signs and management of 4 foals with persistent frenulum of the epiglottis. STUDY DESIGN: Case report. ANIMALS: Four newborn foals. METHODS: Foals were admitted with a complaint of oronasal reflux after nursing. Variable systemic signs of aspiration pneumonia were evident. Nasal endoscopy confirmed persistent dorsal displacement of the soft palate. Persistent frenulum of the epiglottis, confirmed by oral endoscopic examination, was transected. RESULTS: After surgery, all foals had the epiglottis positioned normally, dorsal to the soft palate. Clinical signs of oronasal reflux resolved by the second nursing attempt in 3 foals, whereas this was difficult to assess in one foal that was nursed intermittently because of the mares behavior. This foal died 2 days later. The other 3 foals have had normal epiglottic function for 2-4 years. CONCLUSIONS: Persistent frenulum of the epiglottis should be considered in foals with oronasal reflux from birth. With appropriate medical and surgical management the prognosis for resolution should be good.     

Vaginal Neurofibroma in a Hysterectomized Poodle Dog

A 15‐year‐old, spayed, female poodle dog was presented for evaluation of a mass of tissue prolapsed from the vulva. The dog had been hysterectomized when it was 5 years old. A vaginal mass had been removed approximately 10 months before presentation. Haematological and serum biochemistry analyses demonstrated mild leucocytosis and glycaemia. A vaginal smear was predominantly made up of parabasal cells and intermediate cells with no neoplastic cells. Thoracal and abdominal radiographic findings were unremarkable. The ovaries could not be identified using abdominal ultrasonography. A midline exploratory laparotomy identified both ovaries that were surgically excised. The vaginal mass was also removed following an episiotomy procedure. Histopathological examination of the mass demonstrated that it was a neurofibroma. Both ovaries had cystic changes. Four months after the surgery, the owner reported that the dog was clinically normal. To the authors’ knowledge, this is the first reported case of a vaginal neurofibroma after an incomplete ovariohysterectomy in the dog.     

A lack of antibody formation against inactivated influenza virus after aerosol vaccination in presence or absence of adjuvantia

In the poultry industry, infections with avian influenza virus (AIV) can result in significant economic losses. The risk and the size of an outbreak might be restricted by vaccination of poultry. A vaccine that would be used for rapid intervention during an outbreak should be safe to use, highly effective after a single administration and be suitable for mass application. A vaccine that could be applied by spray or aerosol would be suitable for mass application, but respiratory applied inactivated influenza is poorly immunogenic and needs to be adjuvanted. We chose aluminum OH, chitosan, cholera toxin B subunit (CT-B), and Stimune as adjuvant for an aerosolized vaccine with inactivated H9N2. Each adjuvant was tested in two doses. None of the adjuvanted vaccines induced AIV-specific antibodies after single vaccination, measured 1 and 3 weeks after vaccination by aerosol, in contrast to the intramuscularly applied vaccine. The aerosolized vaccine did enter the chickens' respiratory tract as CT-B-specific serum antibodies were detected after 1 week in chickens vaccinated with the CT-B-adjuvanted vaccine. Chickens showed no adverse effects after the aerosol vaccination based on weight gain and clinical signs. The failure to detect AIV-specific antibodies might be due to the concentration of the inactivated virus.     

Climate Change During the Last Deglaciation in Antarctica

Greenland ice core records provide clear evidence of rapid changes in climate in a variety of climate indicators. In this work, rapid climate change events in the Northern and Southern hemispheres are compared on the basis of an examination of changes in atmospheric circulation developed from two ice cores. High-resolution glaciochemical series, covering the period 10,000 to 16,000 years ago, from a central Greenland ice core and a new site in east Antarctica display similar variability. These findings suggest that rapid climate change events occur more frequently in Antarctica than previously demonstrated.     

Reconstruction of Current Flow and Imaging of Current-Limiting Defects in Polycrystalline Superconducting Films

Magneto-optical imaging was used to visualize the inhomogeneous penetration of magnetic flux into polycrystalline TlBa2Ca2Cu3Ox films with high critical current densities, to reconstruct the local two-dimensional supercurrent flow patterns and to correlate inhomogeneities in this flow with the local crystallographic misorientation. The films have almost perfect c-axis alignment and considerable local a- and b-axis texture because the grains tend to form colonies with only slightly misaligned a and b axes. Current flows freely over these low-angle grain boundaries but is strongly reduced at intermittent colony boundaries of high misorientation. The local (<10-micrometer scale) critical current density Jc varies widely, being up to 10 times as great as the transport Jc (scale of approximately 1 millimeter), which itself varies by a factor of about 5 in different sections of the film. The combined experiments show that the magnitude of the transport Jc is largely determined by a few high-angle boundaries.     

The Self-Assembly Mechanism of Alkanethiols on Au(111)

The self-assembly mechanism of alkanethiol monolayers on the (111) surface of gold was discovered with the use of an ultrahigh-vacuum scanning tunneling microscope. Monolayer formation follows a two-step process that begins with condensation of low-density crystalline islands, characterized by surface-aligned molecular axes, from a lower density lattice-gas phase. At saturation coverage of this phase, the monolayer undergoes a phase transition to a denser phase by realignment of the molecular axes with the surface normal. These studies reveal the important role of molecule-substrate and molecule-molecule interactions in the self-assembly of these technologically important material systems.