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Electron transport in plant cells inevitably results in the creation of reactive oxygen species (ROS) that can hinder metabolic processes and cause cellular damage. In spite of the gains additional antioxidants may impart to the cotton (Gossypium hirsutum L.) photosynthetic apparatus, single time point measurements on live plants have not reflected distinguishable phenotypes for key physiological measures. Transgene efficacy may also be quantified by measuring cumulative agronomic performance (lint yield and quality) under conditions that promote photorespiration and ROS production. To test this hypothesis, cotton lines constitutively expressing the ascorbate peroxidase (APX) or glutathione reductase (GR) protein were examined in field trials (2005, 2006, and 2007) under three different irrigation treatments. Yield, gin turnout, and 23 measures of fiber quality were assessed. Transgene (APX and GR) efficacy and in vitro culture effects were estimated by comparing a line's performance with the null and wild-type checks based on an analysis of variance using a linear mixed model to estimate general least squares and variance components. Significant effects were observed in 18 traits. Despite no significant changes in fiber maturity, all GR and APX transgenic lines produced significantly finer fibers than the wild-type. Fiber maturity is a problem in western Texas that affects most fiber quality measures especially the fineness measurement micronaire.

QTL mapping experiments yield heterogeneous results due to the use of different genotypes, environments, and sampling variation. Compilation of QTL mapping results yields a more complete picture of the genetic control of a trait and reveals patterns in organization of trait variation. A total of 432 QTL mapped in one diploid and 10 tetraploid interspecific cotton populations were aligned using a reference map and depicted in a CMap resource. Early demonstrations that genes from the non-fiber-producing diploid ancestor contribute to tetraploid lint fiber genetics gain further support from multiple populations and environments and advanced-generation studies detecting QTL of small phenotypic effect. Both tetraploid subgenomes contribute QTL at largely non-homeologous locations, suggesting divergent selection acting on many corresponding genes before and/or after polyploid formation. QTL correspondence across studies was only modest, suggesting that additional QTL for the target traits remain to be discovered. Crosses between closely-related genotypes differing by single-gene mutants yield profoundly different QTL landscapes, suggesting that fiber variation involves a complex network of interacting genes. Members of the lint fiber development network appear clustered, with cluster members showing heterogeneous phenotypic effects. Meta-analysis linked to synteny-based and expression-based information provides clues about specific genes and families involved in QTL networks.

The aryl lead halides, {Pb(Mu-Br)ArPr(sub 2)(super i)}2, and the related species {Pb(Mu-Br)ArPr(sub 2)(super i)Bu(super t)}2 are synthesized by treating a diethyl ether suspension of lead(II) bromide with diethyl ether solution of stoichiometric quantity of ArPr(sub 2)(super i)Li or Bu(super t)Pr(sub 2)(super i)ArLi OEt2. Findings show that solution spectroscopic data for all diorganolead derivatives of the ArPr(sub 2)(super i) ligands show that they are exclusively monomeric in solution.

We report genetic maps for diploid (D) and tetraploid (AtDt) Gossypium genomes composed of sequence-tagged sites (STS) that foster structural, functional, and evolutionary genomic studies. The maps include, respectively, 2584 loci at 1.72-cM (~600 kb) intervals based on 2007 probes (AtDt) and 763 loci at 1.96-cM (~500 kb) intervals detected by 662 probes (D). Both diploid and tetraploid cottons exhibit negative crossover interference; i.e., double recombinants are unexpectedly abundant. We found no major structural changes between Dt and D chromosomes, but confirmed two reciprocal translocations between At chromosomes and several inversions. Concentrations of probes in corresponding regions of the various genomes may represent centromeres, while genome-specific concentrations may represent heterochromatin. Locus duplication patterns reveal all 13 expected homeologous chromosome sets and lend new support to the possibility that a more ancient polyploidization event may have predated the A-D divergence of 6-11 million years ago. Identification of SSRs within 312 RFLP sequences plus direct mapping of 124 SSRs and exploration for CAPS and SNPs illustrate the 'portability' of these STS loci across populations and detection systems useful for marker-assisted improvement of the world's leading fiber crop. These data provide new insights into polyploid evolution and represent a foundation for assembly of a finished sequence of the cotton genome.

Metal-metal bonder clusters of the heavier group 13 elements of formula (MR) (sub n) (M=A1-T1, R=organo or related group) are extremely interesting compound class, whose chemistry has undergone rapid development over the past decade. In the neutral gallium aryls, the gallium valence electrons behave essentially as lone pairs rather than bond pairs.

Two interrelated initiatives in early numeracy are briefly described--the Count Me In Too Project in New South Wales, and Mathematics Recovery. The article then focuses on an approach to student assessment which is used in both initiatives. This approach enables teachers to better understand young children's early arithmetical strategies and knowledge. The approach is described in three parts: Part A focuses on initial strategies for addition or subtraction; for example, counting-from-one, counting-on, using finger patterns, and using strategies other than counting by ones. Part B focuses on strategies to solve two-digit subtraction and strategies for incrementing by tens and ones. And Part C focuses on strategies for early multiplication and division. Following this, the strategies which have been described in each part are discussed in terms of their relative sophistication. The discussion includes links to relevant literature and issues relevant to the teaching of early numbers. The conclusion lists six important points about early number teaching and learning., Count Me In Too (CMIT) (Bobis & Gould, 1998, 1999, 2000; NSW Department of Education and Training, 2000) is a systemic initiative operating in NSW government schools since 1996, which [...]

Research has been conducted on the coordinate complexes. The reaction of M{N(SiMe (sub)3) (sub)2} (sub)2 (M= Mn, Re, Co) with different beta-diketimines has produced three-coordinate complexes characterized via magnetic measurements, X-ray crystallography and NMR and IR spectroscopy and the details are included.

A detailed RFLP map was used to determine the chromosomal locations and subgenomic distributions of cotton (Gossypium) genes/QTLs that confer resistance to the bacterial blight pathogen, Xanthomonas campestris pv. malvacearum (Xcm). Genetic mapping generally corroborated classic predictions regarding the number and dosage effects of genes conferring Xcm resistance. One recessive allele ([b.sub.6]) was a noteworthy exception to the genetic dominance of most plant resistance alleles. This recessive allele appeared to uncover additional QTLs from both resistant and ostensibly susceptible genotypes, some of which corresponded in location to resistance (R)-genes effective against other Xcm races. One putatively 'defeated' resistance allele ([B.sub.3]) reduced severity of Xcm damage by 'virulent' races. Among the six resistance genes derived from tetraploid cottons, five (83%) mapped to D-subgenome chromosomes - if each subgenome were equally likely to evolve new R-gene alleles, this level of bias would occur in only about 1.6% of cases. Possible explanations of this bias include biogeographic factors, differences in evolutionary rates between subgenomes, gene conversion or other intergenomic exchanges that escaped detection by genetic mapping, or other factors. A significant D-subgenome bias of Xcm resistance genes may suggest that polyploid formation has offered novel avenues for phenotypic response to selection.

Throughout our history, U.S. presidents have proposed various plans to reorganize the federal government on behalf of the public. Each plan reflects the mood and aspirations of the country at [...]

Reaction of TICI and [LiN(Me)Ar(super Mes2)]2 [Ar(super Mes2)= C6H3-2,6-(C6H2-2,4,6-Me3)2] in Et2O generated the thallium amide, TIN(Me)Ar(super Mes2). The electronic spectrum of [LiN(Me)Ar(super Mes2)]2 is hypsochromically shifted in comparison to the monomeric TlAr(super Trip 2) (Trip=C6H2-2,4,6-Pr(super i 3).

Quercus series Virentes (live oaks) are many independent populations of semievergreen trees common from the southeastern United States to Texas, California, and Mexico. Southern live oak (Q. virginiana Mill.) and Texas live oak (Q. fusiformis Small) are species valued in native and urban landscapes. In Texas, morphological similarities between the standards for these species have complicated classification of individual populations. Classification is further confounded by populations which interact reproductively. Hybrid progeny create opportunity for phenotypic and genotypic diverse Virentes series populations. A putative population of Quercus series Virentes located near Lake Alan Henry, TX was identified. This population is highlighted by a relic individual which appears to be the progenitor of the population. The phylogeny of this specimen was analyzed and compared to other Texas native oak species. Native Quercus accessions were sampled from known locations of Q. fusiformis, the hybrid swarm of Q. virginiana and Q. fusiformis, and other Quercus species. Genetic diversity analysis was conducted using 70 expressed sequence tags. Four genetic clusters were found which represent populations in different terrestrial regions of Texas. Results indicate the Lake Alan Henry, TX specimen, and a second individual located in Elmendorf, TX are relictual trees of Quercus series Virentes populations. [ABSTRACT FROM AUTHOR]

BACKGROUND: Field‐evolved pyrethroid resistance has been confirmed in western corn rootworm (WCR) populations collected from the United States (US) western Corn Belt. Resistance levels of WCR adults estimated in lab bioassays were confirmed to significantly reduce the efficacy of foliar‐applied bifenthrin. The objective of the present study was to investigate the impact of WCR pyrethroid resistance levels on the performance of common soil‐applied insecticide formulations (23.4% tefluthrin, 17.15% bifenthrin, and 0.1% cyfluthrin + 2.0% tebupirimphos). Field trials were conducted in 2016 and 2017 in three Nebraska, US, counties (Saunders, Clay, and Keith) where distinct levels of WCR susceptibility to pyrethroids (susceptible, moderately resistant, and highly resistant) had been previously reported in adult and larval bioassays. RESULTS: All soil insecticide treatments effectively protected maize roots from a pyrethroid‐susceptible WCR population at Saunders. In contrast, the efficacy of bifenthrin and tefluthrin soil insecticides was significantly reduced at Clay and Keith, where pyrethroid‐resistant WCR populations were reported. At Keith, where an additional failure of the cyfluthrin + tebupirimphos soil insecticide was observed, WCR laboratory dose–response bioassays showed a consistent ∼5‐fold resistance level to the active ingredients bifenthrin, tefluthrin, and cyfluthrin. CONCLUSION: The efficacy of common soil insecticides used in the US for WCR management was significantly reduced in populations exhibiting relatively low levels of WCR pyrethroid resistance. Using a multitactical approach to manage WCR within an integrated pest management framework may mitigate resistance evolution and prolong the usefulness of WCR insecticides within the system. © 2019 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

High-pressure gasification processes are important for conversion of solid materials into gaseous fuels and other chemicals. Laser absorption diagnostics are an important means to study these processes, but are challenging to implement due to the extreme temperatures and pressures present in the system. Here, we combine broadband high-resolution dual-comb spectroscopy with an advanced spectral absorption database and a new means for baseline-free absorption spectroscopy analysis to enable measurements of temperature and water vapor concentration in the core of an entrained flow gasifier operating at up to 1700 K and 15 bar. The dual-comb spectrometer measures the absorption of water vapor from 6800 to 7150 cm−1 with a point spacing of 0.0067 cm−1. The bandwidth is helpful for resolving the complex, congested absorption fingerprint of water vapor that is used to determine the species concentrations and temperature. We interpret the spectrum with absorption models based on a database measured under carefully controlled high-temperature conditions with the dual-comb spectrometer. The database includes the pressure broadening, shift, and temperature dependence of these parameters for water vapor in argon, which is the gasifier bath gas. Finally, fitting the absorption model to the data is enabled by modified free induction decay analysis, which is an approach for quantitatively obtaining species and temperature information without determining the baseline intensity of the spectrometer. The baseline-free approach is crucial to success in this environment, where there are no non-absorbing regions of the spectrum to anchor the normalization of the laser intensity as in traditional direct absorption spectroscopy. We demonstrate good agreement with temperatures measured on the reactor core via optical pyrometry, and show that water vapor concentrations in the reactor core did not reach the expected system set points during some experiments. [ABSTRACT FROM AUTHOR]