Asymptotic enumeration of incidence matrices

We discuss the problem of counting {\em incidence matrices}, i.e. zero-one matrices with no zero rows or columns. Using different approaches we give three different proofs for the leading asymptotics for the number of matrices with $n$ ones as $n\to\infty$. We also give refined results for the asymptotic number of $i\times j$ incidence matrices with $n$ ones.Comment: jpconf style files. Presented at the conference "Counting Complexity: An international workshop on statistical mechanics and combinatorics." In celebration of Prof. Tony Guttmann's 60th birthda

Decreased sensitivity to aspirin is associated with altered polyamine metabolism in human prostate cancer cells

Acknowledgments We thank NHS Grampian for financial support of this work.Peer reviewedPublisher PD

Data user's note: Apollo 15 lunar photography

Brief descriptions are given of the Apollo 15 mission objectives, photographic equipment, and photographic coverage and quality. The lunar photographic tasks were: (1) ultraviolet photography of the earth and moon; (2) photography of the gegenschein from lunar orbit; (3) service module orbital photographic tasks; and (4) command module photographic tasks

The instability of stellar structures intermediate between white dwarfs and neutron stars

Instability of stellar structures intermediate between dwarfs and neutron star

Characterization and Commissioning of a Ka-Band Ground Station for Cognitive Algorithm Development

In 2018, the Cognitive Communications and Propagation projects completed installation and checkout testing of a new Ka-Band ground station at the NASA Glenn Research Center in Cleveland, Ohio. The Cognitive Algorithms Demonstration Testbed (CADeT) was developed to provide a fully characterized and controllable dynamic link environment to researchers looking to demonstrate hardware and software aligned with atmospheric sensing and cognitive algorithms. CADeT integrates a host of precision control and measurement systems in addition to repurposing a 5.5 meter beam-waveguide dish platform previously used with the Advanced Communications Technology Satellite (ACTS). This paper will discuss the laboratory testing of ground station components with a emphasis on elements vital to achieving link budget requirements including characterization of the new Gallium Nitride (GaN) Solid State Power Amplifier (SSPA) and far-field measurements of the new antenna feed. Finally, the paper discusses in-situ tests conducted with CADeT and the Tracking and Data Relay Satellite System (TDRSS) to validate laboratory results and make necessary link budget adjustments before reviewing the lessons learned

A comparison of medetomidine and its active enantiomer dexmedetomidine when administered with ketamine in mice

Medetomidine-ketamine (MK) and dexmedetomidine-ketamine (DK) are widely used to provide general anaesthesia in laboratory animals, but have not been compared directly in many of these species, including rodents. This study aimed to compare the onset and depth of anaesthesia, and changes in vital signs, after intraperitoneal (IP) or subcutaneous (SC) administration of ketamine (75 mg kg-1) combined with medetomidine (1 mg kg-1) or dexmedetomidine (0.5 mg kg-1) using a randomised semi-crossover design with >= 48 hours between treatments in 10 male and 10 female mice. Each mouse was anaesthetised twice using the same administration route (IP or SC): once with each drug-ketamine combination. Anaesthetised mice were monitored on a heating pad without supplemental oxygen for 89 minutes; atipamezole was administered for reversal. The times that the righting reflex was lost post-injection and returned post-reversal were analysed using general linear models. Tail-pinch and pedal reflexes were examined using binomial generalized linear models. Pulse rate (PR), respiratory rate (fr), and arterial haemoglobin saturation (SpO2) were compared using generalized additive mixed models. There were no significant differences among treatments for the times taken for loss and return of the righting reflex, or response of the tail-pinch reflex. The pedal withdrawal reflex was abolished more frequently with MK than DK over time (P = 0.021). The response of PR and SpO2 were similar among treatments, but fr was significantly higher with MK than DK (P <= 0.0005). Markedly low SpO2 concentrations occurred within 5 minutes post-injection (83.8 +/- 6.7 %) in all treatment groups and were most severe after 89 minutes lapsed (66.7 +/- 7.5 %). No statistical differences were detected in regards to administration route (P <= 0.94). This study failed to demonstrate clinical advantages of the enantiomer dexmedetomidine over medetomidine when combined with ketamine to produce general anaesthesia in mice. At the doses administered, deep surgical anaesthesia was not consistently produced with either combination; therefore, anaesthetic depth must be assessed before performing surgical procedures. Supplemental oxygen should always be provided during anaesthesia to prevent hypoxaemia