Shepherdson [14] showed that for a discrete ordered ring I, I is a model of IOpen iff I is an integer part of a real closed ordered field. In this paper, we consider integer parts satisfying PA. We show that if a real closed ordered field R has an integer part I that is a nonstandard model of PA (or even IΣ₄), then R must be recursively saturated. In particular, the real closure of I, RC (I), is recursively saturated. We (...) also show that if R is a countable recursively saturated real closed ordered field, then there is an integer part I such that R = RC(I) and I is a nonstandard model of PA. (shrink)

The accurate pricing of securities in the capital markets depends upon the markets being both efficient and fair. In management buyout transactions (MBOs), the price bid by inside managers enhances the efficient pricing of securities but raises a reasonable doubt about the fairness to existing shareholders. This study addresses this fairness question in MBOs and offers short-term and long-term legal alternatives which allow both the efficiency and fairness criteria to be met. In the short-term the case law established in the (...) Basic v. Levinson decision for merger negotiation disclosures should be applied to MBO transactions. Over the longer horizon, legislative changes should be made to existing securities laws. Applying the investor protection principles of the 1933 and 1934 securities acts to MBO transactions will suppress the temptation of managers to extract shareholder wealth for their personal gain. (shrink)

A total of 1918 loci, detected by the hybridization of 938 expressed sequence tag unigenes from 26 Triticeae cDNA libraries, were mapped to wheat homoeologous group 4 chromosomes using a set of deletion, ditelosomic, and nulli-tetrasomic lines. The 1918 EST loci were not distributed uniformly among the three group 4 chromosomes; 41, 28, and 31% mapped to chromosomes 4A, 4B, and 4D, respectively. This pattern is in contrast to the cumulative results of EST mapping in all homoeologous groups, as reported (...) elsewhere, that found the highest proportion of loci mapped to the B genome. Sixty-five percent of these 1918 loci mapped to the long arms of homoeologous group 4 chromosomes, while 35% mapped to the short arms. The distal regions of chromosome arms showed higher numbers of loci than the proximal regions, with the exception of 4DL. This study confirmed the complex structure of chromosome 4A that contains two reciprocal translocations and two inversions, previously identified. An additional inversion in the centromeric region of 4A was revealed. A consensus map for homoeologous group 4 was developed from 119 ESTs unique to group 4. Forty-nine percent of these ESTs were found to be homoologous to sequences on rice chromosome 3, 12% had matches with sequences on other rice chromosomes, and 39% had no matches with rice sequences at all. Limited homology was found between wheat ESTs on homoeologous group 4 and the Arabidopsis genome. Forty-two percent of the homoeologous group 4 ESTs could be classified into functional categories on the basis of blastX searches against all protein databases. (shrink)

The objectives of this study were to develop a high-density chromosome bin map of homoeologous group 7 in hexaploid wheat, to identify gene distribution in these chromosomes, and to perform comparative studies of wheat with rice and barley. We mapped 2148 loci from 919 EST clones onto group 7 chromosomes of wheat. In the majority of cases the numbers of loci were significantly lower in the centromeric regions and tended to increase in the distal regions. The level of duplicated loci (...) in this group was 24% with most of these loci being localized toward the distal regions. One hundred nineteen EST probes that hybridized to three fragments and mapped to the three group 7 chromosomes were designated landmark probes and were used to construct a consensus homoeologous group 7 map. An additional 49 probes that mapped to 7AS, 7DS, and the ancestral translocated segment involving 7BS also were designated landmarks. Landmark probe orders and comparative maps of wheat, rice, and barley were produced on the basis of corresponding rice BAC/PAC and genetic markers that mapped on chromosomes 6 and 8 of rice. Identification of landmark ESTs and development of consensus maps may provide a framework of conserved coding regions predating the evolution of wheat genomes. (shrink)

To localize wheat ESTs on chromosomes, 882 homoeologous group 6-specific ESTs were identified by physically mapping 7965 singletons from 37 cDNA libraries on 146 chromosome, arm, and sub-arm aneuploid and deletion stocks. The 882 ESTs were physically mapped to 25 regions flanked by 23 deletion breakpoints. Of the 5154 restriction fragments detected by 882 ESTs, 2043 were localized to group 6 chromosomes and 806 were mapped on other chromosome groups. The number of loci mapped was greatest on chromosome 6B and (...) least on 6D. The 264 ESTs that detected orthologous loci on all three homoeologs using one restriction enzyme were used to construct a consensus physical map. The physical distribution of ESTs was uneven on chromosomes with a tendency toward higher densities in the distal halves of chromosome arms. About 43% of the wheat group 6 ESTs identified rice homologs upon comparisons of genome sequences. Fifty-eight percent of these ESTs were present on rice chromosome 2 and the remaining were on other rice chromosomes. Even within the group 6 bins, rice chromosomal blocks identified by 1-6 wheat ESTs were homologous to up to 11 rice chromosomes. These rice-block contigs were used to resolve the order of wheat ESTs within each bin. (shrink)

Soil is fragile and nonrenewable but the most basic of natural resources. It has a capacity to tolerate continuous use but only with proper management. Improper soil management and indiscriminate use of chemicals have contributed to some severe global environmental issues, e.g., volatilization losses and contamination of natural waters by sediments and agricultural fertilizers and pesticides. The increasing substitution of energy for labor and other cultural inputs in agriculture is another issue. Fertilizers and chemicals account for about 25% of the (...) production energy investment in agriculture. An additional 60% is accounted for by machinery, gasoline, electricity, and power-related inputs. Fertilizer additions to cropland are not utilized fully and significant amounts, depending on conditions, are either lost in surface runoff or leached into the ground water. The annual discharge of dissolved solids from agricultural lands to the waterways in the USA is substantial. The increasing use of herbicides in agriculture is a threat to the quality of surface and ground water, although this threat is dependent upon both the chemistry of the compound and the ecosystem in which it is used. Especially within the Third World, development of an environmental ethic and environmental laws have not kept pace with the increase in pesticide use. Above all is the severe and global problem of soil degradation currently occurring at the rate of five to seven million hectares per year. The policy and moral aspects of these issues are discussed. (shrink)

Substrate cycles are ubiquitous structures of the cellular metabolism (e.g. Krebs cycle, fatty acids -oxydation cycles, etc... ). Moiety-conserved cycles (e.g. adenine nucleotides and NADH/NAD, etc...) are also important.The role played by such cycles in the metabolism and its regulation is not clearly understood so far. However, it was shown that these cycles can generate multistationarity (bistability), irreversible transitions, enhancement of sensitivity, temporal oscillations and chaotic motions (Hervagault & Canu, 1987; Hervagault & Cimino, 1989; Reich & Sel'kov, 1981; Ricard & (...) Soulié, 1982). Fig. 1: Scheme of the open binary substrate cycle under study. The substrate S is converted into P with a net rate v2. Substrate P is converted in turn into S with a net rate v3. Step v2 is inhibited by excess of the substrate, S. In addition, the cycle operates under open conditions, that is zero-order input of S at rates \ga0(v1) and first order outputs of S and P at rates \gaS and \gaP(v4), respectively. (shrink)

The evolution equations for grain growth and coarsening have been derived in the open literature mainly based on phenomenological considerations. Applying a thermodynamic extremal principle, the evolution equations are derived in a rigorous way. All kinetic parameters are provided directly. Existing relations are proved and generalized.

The complex hexaploid wheat genome offers many challenges for genomics research. Expressed sequence tags facilitate the analysis of gene-coding regions and provide a rich source of molecular markers for mapping and comparison with model organisms. The objectives of this study were to construct a high-density EST chromosome bin map of wheat homoeologous group 2 chromosomes to determine the distribution of ESTs, construct a consensus map of group 2 ESTs, investigate synteny, examine patterns of duplication, and assess the colinearity with rice (...) of ESTs assigned to the group 2 consensus bin map. A total of 2600 loci generated from 1110 ESTs were mapped to group 2 chromosomes by Southern hybridization onto wheat aneuploid chromosome and deletion stocks. A consensus map was constructed of 552 ESTs mapping to more than one group 2 chromosome. Regions of high gene density in distal bins and low gene density in proximal bins were found. Two interstitial gene-rich islands flanked by relatively gene-poor regions on both the short and long arms and having good synteny with rice were discovered. The map locations of two ESTs indicated the possible presence of a small pericentric inversion on chromosome 2B. Wheat chromosome group 2 was shown to share syntenous blocks with rice chromosomes 4 and 7. (shrink)

Objective To evaluate the modes of death and treatment offered in the last 24 h of life to patients dying in 10 Brazilian intensive care units (ICUs) over a period of 2 years. Design and setting Cross-sectional, multicentre, retrospective study based on medical chart review. The medical records of all patients that died in seven paediatric and three adult ICUs belonging to university and tertiary hospitals over a period of 2 years were included. Deaths in the first 24 h of (...) admission to the ICU and brain death were excluded. Intervention Two intensive care fellows of each ICU were trained in fulfilling a standard protocol (κ=0.9) to record demographic data and all medical management provided in the last 48 h of life. The Student t test, Mann–Whitney U test, χ2 test and RR were used for data comparison. Measurements and main results 1053 medical charts were included (59.4% adult patients). Life support limitation was more frequent in the adult group (86% vs 43.5%; p<0.001). A ‘do not resuscitate’ order was the most common life support limitation in both groups (75% and 66%), whereas withholding/withdrawing were more frequent in the paediatric group (33.9% vs 24.9%; p=0.02). The life support limitation was rarely reported in the medical chart in both groups (52.6% and 33.7%) with scarce family involvement in the decision making process (23.0% vs 8.7%; p<0.001). Conclusion Life support limitation decision making in Brazilian ICUs is predominantly centred on the medical perspective with scarce participation of the family, and consequently several non-coherent medical interventions are observed in patients with life support limitation. (shrink)