Movements of Pheasants in Central lowa

A study of pheasant movements in central Iowa during 1961-4 indicated that pheasants tended to move greater distances in spring as they dispersed from winter concentration areas than at other times of the year. Movements during this period averaged 0.9 mile. During the winter, movements were much more restricted, averaging only 0.2 mile; however, this may have been due in part to the unusually severe weather conditions that prevailed during the particular winter in which movements were studied. Compared with other areas in the Iowa and Midwest pheasant range, there appeared no detectable differences in the length or type of movement, which might help account for the generally poor pheasant populations that occur in this area at the edge of the major Iowa pheasant range

Size-dependent Catalysis of Chlorovirus Population Growth by a Messy Feeding Predator

Many chloroviruses replicate in endosymbiotic zoochlorellae that are protected from infection by their symbiotic host. To reach the high virus concentrations that often occur in natural systems, a mechanism is needed to release zoochlorellae from their hosts. We demonstrate that the ciliate predator Didinium nasutum foraging on zoochlorellae-bearing Paramecium bursaria can release live zoochlorellae from the ruptured prey cell that can then be infected by chloroviruses. The catalysis process is very effective, yielding roughly 95% of the theoretical infectious virus yield as determined by sonication of P. bursaria. Chlorovirus activation is more effective with smaller Didinia, as larger Didinia typically consume entire P. bursaria cells without rupturing them, precluding the release of zoochlorellae. We also show that the timing of Chlorovirus growth is tightly linked to the predator-prey cycle between Didinium and Paramecium, with the most rapid increase in chloroviruses temporally linked to the peak foraging rate of Didinium, supporting the idea that predator-prey cycles can drive cycles of Chlorovirus abundance

Variable Sampling Mapping

The performance of an optical system (for example, a telescope) is limited by the misalignments and manufacturing imperfections of the optical elements in the system. The impact of these misalignments and imperfections can be quantified by the phase variations imparted on light traveling through the system. Phase retrieval is a methodology for determining these variations. Phase retrieval uses images taken with the optical system and using a light source of known shape and characteristics. Unlike interferometric methods, which require an optical reference for comparison, and unlike Shack-Hartmann wavefront sensors that require special optical hardware at the optical system's exit pupil, phase retrieval is an in situ, image-based method for determining the phase variations of light at the system s exit pupil. Phase retrieval can be used both as an optical metrology tool (during fabrication of optical surfaces and assembly of optical systems) and as a sensor used in active, closed-loop control of an optical system, to optimize performance. One class of phase-retrieval algorithms is the iterative transform algorithm (ITA). ITAs estimate the phase variations by iteratively enforcing known constraints in the exit pupil and at the detector, determined from modeled or measured data. The Variable Sampling Mapping (VSM) technique is a new method for enforcing these constraints in ITAs. VSM is an open framework for addressing a wide range of issues that have previously been considered detrimental to high-accuracy phase retrieval, including undersampled images, broadband illumination, images taken at or near best focus, chromatic aberrations, jitter or vibration of the optical system or detector, and dead or noisy detector pixels. The VSM is a model-to-data mapping procedure. In VSM, fully sampled electric fields at multiple wavelengths are modeled inside the phase-retrieval algorithm, and then these fields are mapped to intensities on the light detector, using the properties of the detector and optical system, for comparison with measured data. Ultimately, this model-to-data mapping procedure enables a more robust and accurate way of incorporating the exit-pupil and image detector constraints, which are fundamental to the general class of ITA phase retrieval algorithms

Systematic assessment of pathway databases, based on a diverse collection of user-submitted experiments

A knowledge-based grouping of genes into pathways or functional units is essential for describing and understanding cellular complexity. However, it is not always clear a priori how and at what level of specificity functionally interconnected genes should be partitioned into pathways, for a given application. Here, we assess and compare nine existing and two conceptually novel functional classification systems, with respect to their discovery power and generality in gene set enrichment testing. We base our assessment on a collection of nearly 2000 functional genomics datasets provided by users of the STRING database. With these real-life and diverse queries, we assess which systems typically provide the most specific and complete enrichment results. We find many structural and performance differences between classification systems. Overall, the well-established, hierarchically organized pathway annotation systems yield the best enrichment performance, despite covering substantial parts of the human genome in general terms only. On the other hand, the more recent unsupervised annotation systems perform strongest in understudied areas and organisms, and in detecting more specific pathways, albeit with less informative labels

G91-1026 Sunflower Production in Nebraska

Seeds, seedbed preparations, fertilizing and controlling weeds in sunflowers are among the topics covered here. Sunflowers are native to Nebraska. Cultivated for centuries by native American Indians as a food crop, sunflowers were taken to Europe in the mid-16th century. Oilseed sunflowers have been a U.S. crop since 1986. Sunflower production is divided into two market classes, oil and confectionery. The oil type is by far the most commonly grown market class. Recent health trends have brought sunflower cooking oil into prominence because the oil is low in saturated fats. Confectionery types are grown for the edible roasted sunflower seed market, and are produced under strict contract guidelines. Seed size is critical, with small seeds designated for bird seed market channels. Growing the confectionery type without a contract is risky. Sunflower production of both market classes is currently around 30,000 acres in Nebraska. Recently a third market class has started to develop based on high oleic acid content, which gives products better shelf life

Raising a Small Flock of Sheep in Ohio

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Towards a fullerene-based quantum computer

Molecular structures appear to be natural candidates for a quantum technology: individual atoms can support quantum superpositions for long periods, and such atoms can in principle be embedded in a permanent molecular scaffolding to form an array. This would be true nanotechnology, with dimensions of order of a nanometre. However, the challenges of realising such a vision are immense. One must identify a suitable elementary unit and demonstrate its merits for qubit storage and manipulation, including input / output. These units must then be formed into large arrays corresponding to an functional quantum architecture, including a mechanism for gate operations. Here we report our efforts, both experimental and theoretical, to create such a technology based on endohedral fullerenes or 'buckyballs'. We describe our successes with respect to these criteria, along with the obstacles we are currently facing and the questions that remain to be addressed.Comment: 20 pages, 13 figs, single column forma