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Female advertisement of reproductive state and receptivity has the potential to play a large role in the mating systems of many taxa, but investigations of this phenomenon are underrepresented in the literature. North American red squirrels (Tamiasciurus hudsonicus) are highly territorial and engage in scramble competition mating, with males converging from spatially disparate territories to engage in mating chases. Given the narrow estrus window exhibited in this species, the ubiquitous use of vocalizations to advertise territory ownership, and the high synchronicity of males arriving from distant territories, we hypothesized that female vocalizations contain cues relating to their estrous state. To test this hypothesis, we examined the spectral and temporal properties of female territorial rattle vocalizations collected from females of known reproductive condition over 3 years. While we found no distinct changes associated with estrus specifically, we did identify significant changes in the spectral characteristics of rattles relating to both female body mass and reproductive state relative to parturition. To the best of our knowledge, this is the first evidence of changes in vocal characteristics associated with late pregnancy in a nonhuman mammal.Despite no evidence that vocal cues relating to estrus are communicated in the North American Red Squirrel, we found that female vocal characteristics showed significant variation related to both reproductive state and body mass. To our knowledge, this is the first evidence of vocal changes associated with pregnancy in a nonhuman mammal.

What is the XM395 PGMM? A precision guided mortar munition (PGMM) is a multipurpose laser-guided 120mm precision mortar round that will defeat personnel under protective cover (earth and timber bunkers, [...]

Presents three scan line methods for drawing pictures of parametrically defined surfaces. Characterization of scan line algorithm; Inversion of the function to define the surface; Overview of scan line methods.

Giving value to both customers and shareholders can be a tricky business. Customer productivity is one way of achieving this goal A revolution is exploding in the pulp, paper and [...]

AbstractCOBRA-IE is a three-field subchannel analysis code that was originally based on the COBRA-TF code series. The default interfacial drag model in COBRA-IE has been assessed against a wide range of pressure drop data taken in confined geometries and has been shown to perform very well. The difference in interfacial drag behavior for confined flow paths compared to large open regions where the bubbles are not constrained by the physical geometry of the flow path has been well documented in the open literature. Therefore, a dedicated interfacial drag model for large, open regions has been developed and implemented in COBRA-IE. This alternative interfacial drag model is based on the drift flux formulation and is activated by user input. A combination of the Kataoka-Ishii and the Zuber-Findley drift flux correlations has been implemented in COBRA-IE to calculate the weighted mean drift velocity and distribution parameter. The implementation of the model is described in this paper, and the interface functions to transition between the drift flux and two-fluid formulations are emphasized.An assessment of the predictive capability of COBRA-IE for the transient level swell phenomena for the experiments performed by General Electric (GE) has been performed. Level swell is an important phenomenon for reactor safety analysis because it impacts water distribution within the reactor vessel during the blowdown phase of the transient as well as the residual inventory available to provide core cooling. The initial assessment of the code using the default interfacial drag modeling package showed an overprediction of the level swell and liquid carryover for the GE experiments, which is indicative of an overprediction of the interfacial drag for these situations. In addition to using the new code to reexamine the GE level swell experiment, assessments of the new model have been performed using the steady-state void fraction data collected in the Beattie-Sugawara and Smith experiments and are presented in this paper.

Endotoxins are stimulators of the immune system and, despite their potential to protect against allergy, have been associated with early wheezing and asthma morbidity.

A three-field countercurrent flow limitation (CCFL) model based on the classic flooding curve methodology has been developed and successfully demonstrated in a derivative of the COBRA-TF code. The various physical mechanisms (wave reversal, liquid bridging, and wave interfacial instability) supposed to govern the flooding and flow reversal phenomena are extremely complex and geometric dependent. As a result universally applicable numerical models for these phenomena are not currently available. The chosen approach provides flexibility and leverages the available experimental data to improve the predictive capability of the code. The model is an extension of the standard two-field (liquid-vapor) CCFL model to a three-field (liquid films, vapor, and liquid droplets) CCFL model. This extension includes providing the appropriate set of momentum equations, definitions of required superficial velocities, and new entrainment rate correlations based on CCFL conditions. Necessary criteria to enter and exit the model in a numerically stable manner are also described. The implementation of the model was verified and was shown to provide increased numerical stability in the code predictions. Improvement in the code-to-data agreement of the allowable downward liquid penetration rate for the Dukler and Smith experiments is also demonstrated.

The production of heterologous proteins in plants at levels consistent with commercialization requires molecular tools to ensure high-level transgene expression. The identification of strong promoters, preferably specific to the target expression tissue, is a focus for improving foreign protein yields using transgenic cereals as a production system. Thus, there is a requirement for strong embryo preferred monocot promoters. We obtained the sequences of 500 randomly selected maize cDNA clones to determine gene expression profiles in embryo tissues at multiple stages during development. Promoters corresponding to the most abundant clones were identified and isolated. These promoters were fused to the b-glucuronidase reporter and their tissue specificity and developmental expression characteristics assessed in transgenic maize. All of the isolated promoters tested drove transgene expression predominantly in the embryo and were most active late in embryogenesis during storage protein deposition. One of the most active promoters assessed by transgene expression was associated with the globulin-1 protein. Sequence identified here extended approximately 1.6 kb distal to the previously identified extent of the globulin-1promoter, and this additional sequence boosted expression over two-fold. The extended globulin-1promoter sequence isolated in this study has the potential for driving transgene expression at higher levels than those previously reported for cereals. Also, the highly active embryo promoters identified here offer opportunities to express multiple foreign proteins simultaneously at high levels in embryo tissues, while avoiding concerns over gene silencing due to the repeated use of a single promoter.

The association between allergens in schools and childhood asthma has not been well studied, particularly in the United States.

RELAP5-3D currently calculates two-phase pump degradation using the Aerojet Nuclear Corporation (ANC) model. This is an empirical model that relates two-phase pump performance to single-phase pump performance using a set of two-phase degradation multipliers, which are only a function of void fraction. The purpose of the present work was to assess the two-phase pump degradation model in RELAP5-3D and various sets of user-supplied two-phase degradation multipliers by modeling a full-scale, two-phase pump test facility and comparing the simulated results to experimental data. Tests conducted by Ontario Hydro Technologies (OHT) using a full-size CANDU reactor primary heat transport pump were used for this assessment. Presently, this work represents the only RELAP5-3D analysis of these tests that has been performed.The experimental data from the OHT tests and results of this assessment both indicate that there is a pressure effect, in addition to void fraction, that cannot be neglected by safety analysis codes when predicting two-phase pump performance. The RELAP5-3D results showed that the widely used Semiscale two-phase head degradation multipliers did a poor job of predicting the experimental data and utilizing pressure-specific two-phase head degradation multipliers developed by OHT significantly improved code-to-data agreement. These results identify both the inaccuracies of using the Semiscale two-phase degradation multipliers and a weakness in the present formulation of the ANC model. As a result of this work, the Idaho National Laboratory recognized the need to include a pressure dependence in the RELAP5-3D calculation of two-phase pump performance, and this capability will be available in the next release of the code.

Summary: Hybrid embryos resulting from crosses between a highly regenerable maize germplasm (Hi II) and certain elite inbreds were treated with Agrobacterium tumefaciens containing the uidA (GUS) and pat genes under the control of different constitutive promoters. Six of the elite inbred lines were derived from a Lancaster background and three were derived from an Iowa Stiff Stalk background. Hybrid embryos from all three Stiff Stalk lines gave transgenic events at various frequencies, two of them at a comparable frequency to that observed with Hi II embryos. Embryos from only one Lancaster/Hi II hybrid were successfully transformed and the frequency was quite low. Additional Lancaster elite inbreds were then tested as a hybrid with Hi II and failed to produce a single transgenic event. The transgenic Hi II/elite events showed many characteristics of ‘hybrid vigor’ including more aggressive rooting, thicker stems, and taller stature than plants derived from Hi II events. The hybrid T0 plants exhibited excellent tassel development in the greenhouse with abundant pollen shed. Seed set in the greenhouse was significantly (3–5-fold) higher than with Hi II transformats. Attempts to transform embryos derived from self or sibling crosses of the four inbred lines that were successful as hybrids with Hi II did not produce any transgenic events. T0 plants having ∼50% elite genomic contribution perform nearly as well in the greenhouse as seed-derived elite inbred parents and offer a significantly reduced time line for recombinant protein product development from transgenic plants.

Methods are given for isolating and approximating the maxima, minima, and real roots of a polynomial with real coefficients. The methods are based on a variation diminishing property of the Bernstein coefficients of the polynomial and use of a recursive bisection technique.

Elevations in glucocorticoid (GC) levels in breeding females may induce adaptive shifts in offspring life histories. Offspring produced by mothers with elevated GCs may be better prepared to face harsh environments, where a faster pace of life is beneficial. We examined how experimentally elevated GCs in pregnant or lactating North American red squirrels (Tamiasciurus hudsonicus) affected offspring postnatal growth, structural size and oxidative stress levels (two antioxidants and oxidative protein damage) in three different tissues (blood, heart and liver) and liver telomere lengths. We predicted that offspring from mothers treated with GCs would grow faster but would also have higher levels of oxidative stress and shorter telomeres, which may predict reduced longevity. Offspring from mothers treated with GCs during pregnancy were 8.3% lighter around birth but grew (in body mass) 17.0% faster than those from controls, whereas offspring from mothers treated with GCs during lactation grew 34.8% slower than those from controls and did not differ in body mass around birth. Treating mothers with GCs during pregnancy or lactation did not alter the oxidative stress levels or telomere lengths of their offspring. Fast-growing offspring from any of the treatment groups did not have higher oxidative stress levels or shorter telomere lengths, indicating that offspring that grew faster early in life did not exhibit oxidative costs after this period of growth. Our results indicate that elevations in maternal GCs may induce plasticity in offspring growth without long-term oxidative costs to the offspring that might result in a shortened lifespan.

Phenotypic plasticity—one individual's capacity for phenotypic variation under different environments—is critical for organisms facing fluctuating conditions within their lifetime. North American red squirrels (Tamiasciurus hudsonicus) experience drastic among-year fluctuations in conspecific density. This shapes juvenile competition over vacant territories and overwinter survival. To help young cope with competition at high densities, mothers can increase offspring growth rates via a glucocorticoid-mediated maternal effect. However, this effect is only adaptive under high densities, and faster growth often comes at a cost to longevity. While red squirrels can adjust hormones in response to fluctuating density, the degree to which mothers differ in glucocorticoid plasticity across changing densities remains unknown. Findings from our reaction norm approach revealed significant individual variation not only in a female red squirrel's mean endocrine phenotype but also in endocrine plasticity in response to changes in local density. Future work on proximate and ultimate drivers of variation in endocrine plasticity and maternal effects is needed, particularly in free-living animals experiencing fluctuating environments.

The article reports that in July 2011, Gilead Sciences Inc. became the first pharmaceutical company to license drug technology to the new international Medicines Patent Pool (Pool). It is mentioned that Gilead licensed five of its HIV/AIDS drugs to the Pool, and as many as five other pharmaceutical companies, including Bristol-Myers Squibb, ViiV Healthcare, and Roche.