Enhancements to the IBM version of COSMIC/NASTRAN

Major improvements were made to the IBM version of COSMIC/NASTRAN by RPK Corporation under contract to IBM Corporation. These improvements will become part of COSMIC's IBM version and will be available in the second quarter of 1989. The first improvement is the inclusion of code to take advantage of IBM's new Vector Facility (VF) on its 3090 machines. The remaining improvements are modifications that will benefit all users as a result of the extended addressing capability provided by the MVS/XA operating system. These improvements include the availability of an in-memory data base that potentially eliminates the need for I/O to the PRIxx disk files. Another improvement is the elimination of multiple load modules that have to be loaded for every link switch within NASTRAN. The last improvement allows for NASTRAN to execute above the 16 mega-byte line. This improvement allows for NASTRAN to have access to 2 giga-bytes of memory for open core and the in-memory data base

Economic inequality increases risk taking

Income inequality is rising around the world. Increased income inequality has been linked with higher rates of crime, greater debt, and poorer health, but the mechanisms linking inequality to poor outcomes among individuals are poorly understood. This research tested a behavioral account linking inequality to individual decision making. The account suggests that more unequal outcomes lead people to perceive that they need more resources to be satisfied. Higher perceived needs, in turn, motivate greater risk taking to meet those needs. Results of three experiments and an analysis of large-scale internet search data supported the proposed account. Results suggest that inequality may promote a range of poor outcomes, in part, by increasing risky behavior

Bayesian Reconstruction of Magnetic Resonance Images using Gaussian Processes

A central goal of modern magnetic resonance imaging (MRI) is to reduce the time required to produce high-quality images. Efforts have included hardware and software innovations such as parallel imaging, compressed sensing, and deep learning-based reconstruction. Here, we propose and demonstrate a Bayesian method to build statistical libraries of magnetic resonance (MR) images in k-space and use these libraries to identify optimal subsampling paths and reconstruction processes. Specifically, we compute a multivariate normal distribution based upon Gaussian processes using a publicly available library of T1-weighted images of healthy brains. We combine this library with physics-informed envelope functions to only retain meaningful correlations in k-space. This covariance function is then used to select a series of ring-shaped subsampling paths using Bayesian optimization such that they optimally explore space while remaining practically realizable in commercial MRI systems. Combining optimized subsampling paths found for a range of images, we compute a generalized sampling path that, when used for novel images, produces superlative structural similarity and error in comparison to previously reported reconstruction processes (i.e. 96.3% structural similarity and <0.003 normalized mean squared error from sampling only 12.5% of the k-space data). Finally, we use this reconstruction process on pathological data without retraining to show that reconstructed images are clinically useful for stroke identification

Temperatures experienced by fresh-cut leafy greens during retail storage and display

There has been limited published work in the United States on temperature profiling of fresh-cut, bagged leafy greens during their transport, retail storage, and retail display. This study utilized temperature monitors placed in backrooms and display cases at nine supermarkets located in southern California: the Central Coast (Santa Barbara to Los Osos), Greater Los Angeles (Burbank area), and Greater Palm Desert. Sensors were installed midway along each 8-foot display case section containing fresh-cut leafy greens. Monitors were placed at the front and back of shelves and in the lower bin. In storage rooms, sensors were placed 4 feet from the floor in each corner. High and low temperature abuse occurred in retail display cases, with slightly more than 40% of the sensors indicating temperatures \u3e7.22°C, and 17% of the sensors indicating temperatures \u3c-0.17°C, for at least 5% of the time. Temperatures in storage rooms were rarely too low, but were often too high: slightly more than 58% of the sensors indicated temperatures \u3e7.22°C more than 5% of the time, and five sensors measured continuous temperatures \u3e7.22°C for nearly a year. Overall, most temperature abuse of pre-cut leafy greens at the retail level occurred during backroom storage. This study should be expanded to include major grocery chains in cities across the United States in order to verify these results

Hybrid squeezing of solitonic resonant radiation in photonic crystal fibers

We report on the existence of a novel kind of squeezing in photonic crystal fibers which is conceptually intermediate between the four-wave mixing induced squeezing, in which all the participant waves are monochromatic waves, and the self-phase modulation induced squeezing for a single pulse in a coherent state. This hybrid squeezing occurs when an arbitrary short soliton emits quasi-monochromatic resonant radiation near a zero group velocity dispersion point of the fiber. Photons around the resonant frequency become strongly correlated due to the presence of the classical soliton, and a reduction of the quantum noise below the shot noise level is predicted.Comment: 5 pages, 2 figure

Distribution and Diet of Ivory Gulls (Pagophila eburnea) in the North Water

Ivory gulls (Pagophila eburnea, Phipps, 1774), one of the world’s least-known species, have declined throughout their range in recent years. This study describes the patterns of ivory gull use of the North Water polynya, a large polynya that occurs every year near ivory gull breeding sites on Ellesmere Island, Nunavut, Canada. We conducted at-sea surveys from Canadian icebreakers during the summers of 1997–99. In 1998, stomach contents of five ivory gulls were analyzed. We measured stable isotope ratios (d13C, d15N) of liver, muscle, feather and bone to determine how ivory gull diets vary during the year. We observed a total of 275 individuals, most of which were seen on the western side of the polynya. Flying was the predominant behavior (76% of individuals); other behaviors included sitting on ice, sitting on water, and feeding. Four juveniles were seen in August and September. Birds collected had arctic cod (Boreogadus saida) in their stomachs. Other food items included an otolith from an unidentified species of Liparid fish and two bones from a mole, presumed to be a star-nosed mole (Condylura cristata). Stable isotope results indicated that ivory gull trophic levels (TLs) were high (around TL 4 based on d15N) but varied over the season. From the three individuals whose feathers were analyzed, we conclude that differences among individuals in their winter diets or foraging locations are possible.Les mouettes blanches (Pagophila eburnea), soit l’une des espèces les moins connues dans le monde, ont enregistré un déclin à travers l’ensemble de leurs habitats ces dernières années. Cette étude décrit les habitudes des mouettes blanches dans la polynie des eaux du Nord, une grande polynie qui se développe chaque année près des sites de reproduction de mouettes blanches sur l’île Ellesmere, au Nunavut, Canada. Nous avons effectué des relevés depuis des brise-glace canadiens au cours des étés 1997 à 1999. En 1998, le contenu des estomacs de cinq mouettes blanches a été analysé. Nous avons également mesuré les ratios d’isotopes stables (d13C, d15N) dans les foies, les muscles, les plumages et les os afin de déterminer comment le régime alimentaire des mouettes blanches variait au cours de l’année. Nous avons observé 275 individus, provenant principalement du côté ouest de la Polynie. La majorité (76 %) étaient en vol. Parmi les autres comportements observés, notons la présence d’oiseaux sur la glace, d’oiseaux sur l’eau et d’oiseaux en train de se nourrir. Quatre oiseaux juvéniles ont été repérés en août et en septembre. Les oiseaux capturés avaient de la morue polaire (Boreogadus saida) dans l’estomac. Les autres aliments trouvés comprenaient un otolithe provenant d’une espèce non identifiée de poisson Liparidé, et deux os de taupe, probablement un condylure étoilé (Condylura cristata). L’analyse des isotopes stables indique que les niveaux trophiques (NT) des mouettes blanches étaient élevés (NT 4 environ en fonction de d15N), mais variaient au cours de la saison. À partir des trois individus dont les plumes ont été analysées, nous en avons conclu qu’il est possible qu’il existe des différences entre les régimes d’hiver ou les lieux de nourriture des individus