Estimates of quantitave genetic parameters in IAP2B random-mating sorghum population

Seed composition from S[subscript]1 families of C0, C2, C3, C4, and half-sib families of C1, C2, C3, and C4, together with 60 individual S[subscript]1 families chosen randomly from C0 and C4 of sorghum (Sorghum bicolor (L.) Moench) population IAP2B were evaluated in five Iowa environments;Four cycles of gridded mass selection of individual-panicle grain weight shifted the mean for grain yield favorably, and the range among S[subscript]1 families was extended. Increased values in C4 also were observed for seeds/panicle, 100-seed weight, days to midbloom, and plant height, but panicles/plant decreased. Genotypic variance among S[subscript]1 families increased from C0 to C4 for grain yield and days to midbloom. Estimates of inbreeding depression were significant (p \u3c 0.05 or 0.01) for grain yield (-18.2%), panicles/plant (-13.7%), plant height (-11.5%), and 100-seed weight (-8.4%). Appreciable nonadditive gene action was expressed for those traits. Seeds/panicle and days to midbloom displayed additive gene action;Heritability estimates for grain yield increased from C0 to C4, but they decreased for panicles/plant. Expected gain/year for grain yield by using S[subscript]1 family selection increased from C0 (2.0% of the mean) to C4 (3.2%). Estimates for C0 vs C4 showed a decrease for panicles/plant (from 4.5% to 3.6% of the mean);Correlation coefficients indicated that selection for individual-panicle grain weight also influenced other characters. Correlations changed substantially in a positive direction from C0 to C4 for grain yield vs seeds/panicle, grain yield vs panicles/plant, and seeds/panicle vs panicles/plant, but they changed in a negative manner for grain yield vs 100-seed weight;Parameters estimated for the S[subscript]1 families and cycle composites indicated that IAP2B(M) should prove useful for developing female parents with a wide array of gene combinations. The higher estimates of genotypic variance and heritability for grain yield in C4, as well as the larger estimates of expected gain from S[subscript]1 family selection, indicated that further improvement of the population should be expected with additional cycles of recurrent selection

The Costs of Domestic Political Unrest

Does domestic political unrest deter foreign direct investment (FDI)? And what are the longer term impacts of unrest upon the market? Most theories suggest that investors are deterred by unrest. However, empirical research returns only marginal support. We argue that these mixed results stem from the conflation of the distinct tactics and outcomes of political unrest. Violent forms of unrest increase uncertainty and risk. By comparison, nonviolent forms of unrest are shown to more frequently achieve their goals and increase the prospects for democratic change and market stability. In addition, investors avoid markets where campaigns have ended in failure, defined as the campaign not achieving their stated political aims. Failed campaigns often precipitate a cycle of unrest that create greater uncertainty over the long-term stability of a state. We find strong evidence in favor of our propositions, even after taking political motivation and non-random selection into account. © 2013 International Studies Association

Agronomic Performance of Sorghum Hybrids Produced by using Different Male-sterility-inducing Cytoplasms

Experiments were conducted in three environments in Iowa to obtain information on the effects of different cytoplasms on agronomic characters in grain sorghum (Sorghum bicolor L. Moench) hybrids. Compared with A1 cytoplasm, A2 and A3 cytoplasms delayed flowering; reduced the percentage of fertile pollen, the number of seeds per panicle, and grain yield; and increased 100-seed weight of the hybrids. Hybrids with A2 or A3 cytoplasm did not differ (p ≥0.05) from those in the A1 cytoplasm for plant height, panicles per plant, or for length, width, and area of the third and fourth leaves from the top of the plant. A2-cytoplasm hybrids did not differ (p ≥0.05) from those in A3 cytoplasm for any of the traits measure. The results are discussed relative to the performance of hybrids with pollen fertility restored and not restored

Estimates of Quantitative Genetic Parameters m IAP2B(M) Random-Mating Sorghum Population

Random-mating populations of sorghum [Sorghum bicolor (L.) Moench] are used extensively as germ plasm in the development of parental lines for hybrids. Populations improved by recurrent selection provide a useful source for the selection of superior parental lines. Our objective was to determine the effectiveness of mass selection for threshed-panicle weight by comparing the performance of lines (S1 families) chosen randomly from CO and C4 of sorghum population IAP2B. Sixty S1 families from each cycle were grown in five Iowa environments. Four cycles of selection for panicle weight shifted the mean for grain yield favorably, and the range among families was extended. Increased values in C4 also were observed for seeds/panicle, 100-seed weight, days to midbloom, and plant height, but panicles/plant decreased. Genotypic variance among S1 families increased from CO to C4 for grain yield and days to midbloom. Heritability estimates for grain yield also increased from CO to C4. Expected gain/year for grain yield by using S1 family selection increased from 2.0% of the mean for CO data to 3.2% for C4. Correlation coefficients indicated that selection for individual-panicle grain weight also influenced other characters. Correlations changed substantially in a positive direction from CO to C4 for grain yield vs. seeds/panicle and grain yield vs. panicles/plant, but they changed in a negative manner for grain yield vs. 100-seed weight. IAP2B(M) should prove useful for developing female parents with a wide array of gene combinations. Higher estimates of genotypic variance and heritability for grain yield in C4 compared to CO, as well as greater expected gain in C4 from S1 family selection, indicated that further improvement of the population should be expected with additional cycles of selection

Negative pressure pulmonary edema causing postoperative hypoxemia: is there a relationship with the administration of sugammadex?

Negative pressure pulmonary edema is an uncommon cause of postoperative hypoxemia. Following upper air- way obstruction, negative pressure pulmonary edema oc- curs due to the generation of negative intrathoracic pres- sure by forceful inhalation against an obstructed upper airway. This complication has previously been described in the context of laryngospasm during anesthetic care as well as a variety of other clinical scenarios including strangulation, foreign body aspiration, and obstructive sleep apnea. In the postoperative patient, management of this complication requires recognition and differentiation from other etiologies of hypoxemia. We present a 17- year-old adolescent who developed hypoxemia in the post-anesthesia care unit due to negative pressure pulmo- nary edema following laryngospasm during emergence from anesthesia and tracheal extubation. The differential diagnosis of postoperative hypoxemia in an otherwise healthy patient is presented, investigative work-up re- viewed, and treatment options discussed. Additionally, the anecdotal association of sugammadex with NPPE is outlined

Identification of Retinal Transformation Hot Spots in Developing Drosophila Epithelia

Background: The retinal determination (RD) network is an evolutionarily conserved regulatory circuit that governs early events in the development of eyes throughout the animal kingdom. Ectopic expression of many members of this network leads to the transformation of non-retinal epithelia into eye tissue. An often-overlooked observation is that only particular cell-populations within a handful of tissues are capable of having their primary developmental instructions superseded and overruled. Methodology/Preliminary Findings: Here we confirm that indeed, only a discrete number of cell populations within the imaginal discs that give rise to the head, antenna, legs, wings and halteres have the cellular plasticity to have their developmental fates altered. In contrast to previous reports, we find that all transformable cell populations do not lie within the TGFb or Hedgehog signaling domains. Additionally neither signaling cascade alone is sufficient for non-retinal cell types to be converted into retinal tissue. The transformation ‘‘hot spots’ ’ that we have identified appear to coincide with several previously defined transdetermination ‘‘weak spots’’, suggesting that ectopic eye formation is less the result of one network overriding the orders of another, as previously thought, but rather is the physical manifestation of redirecting cell populations of enormous cellular plasticity. We also demonstrate that the initiation of eye formation in non-retinal tissues occurs asynchronously compared to that of the normal eye suggesting that retinal development is not under the control o

Expression of Distal-less, dachshund, and optomotor blind in Neanthes arenaceodentata (Annelida, Nereididae) does not support homology of appendage-forming mechanisms across the Bilateria

The similarity in the genetic regulation of arthropod and vertebrate appendage formation has been interpreted as the product of a plesiomorphic gene network that was primitively involved in bilaterian appendage development and co-opted to build appendages (in modern phyla) that are not historically related as structures. Data from lophotrochozoans are needed to clarify the pervasiveness of plesiomorphic appendage forming mechanisms. We assayed the expression of three arthropod and vertebrate limb gene orthologs, Distal-less (Dll), dachshund (dac), and optomotor blind (omb), in direct-developing juveniles of the polychaete Neanthes arenaceodentata. Parapodial Dll expression marks premorphogenetic notopodia and neuropodia, becoming restricted to the bases of notopodial cirri and to ventral portions of neuropodia. In outgrowing cephalic appendages, Dll activity is primarily restricted to proximal domains. Dll expression is also prominent in the brain. dac expression occurs in the brain, nerve cord ganglia, a pair of pharyngeal ganglia, presumed interneurons linking a pair of segmental nerves, and in newly differentiating mesoderm. Domains of omb expression include the brain, nerve cord ganglia, one pair of anterior cirri, presumed precursors of dorsal musculature, and the same pharyngeal ganglia and presumed interneurons that express dac. Contrary to their roles in outgrowing arthropod and vertebrate appendages, Dll, dac, and omb lack comparable expression in Neanthes appendages, implying independent evolution of annelid appendage development. We infer that parapodia and arthropodia are not structurally or mechanistically homologous (but their primordia might be), that Dll’s ancestral bilaterian function was in sensory and central nervous system differentiation, and that locomotory appendages possibly evolved from sensory outgrowths