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Species diversity can be lost through two different but potentially interacting extinction processes: demographic decline and speciation reversal through introgressive hybridization. To investigate the relative contribution of these processes, we analysed historical and contemporary data of replicate whitefish radiations from 17 pre-alpine European lakes and reconstructed changes in genetic species differentiation through time using historical samples. Here we provide evidence that species diversity evolved in response to ecological opportunity, and that eutrophication, by diminishing this opportunity, has driven extinctions through speciation reversal and demographic decline. Across the radiations, the magnitude of eutrophication explains the pattern of species loss and levels of genetic and functional distinctiveness among remaining species. We argue that extinction by speciation reversal may be more widespread than currently appreciated. Preventing such extinctions will require that conservation efforts not only target existing species but identify and protect the ecological and evolutionary processes that generate and maintain species. Historical and contemporary data of whitefish radiations from pre-alpine European lakes and reconstruction of changes in whitefish genetic species differentiation through time show that species diversity may have evolved in response to ecological opportunity, and that eutrophication, by diminishing this opportunity, has driven extinctions through speciation reversal and demographic decline. Extinction through reversed speciation Species extinctions happen in two very different ways. In the first, there can be a simple population decline. Less obvious is a second mechanism, in which previously distinct species merge through a reversal of the speciation process. This process reduces biodiversity, but not necessarily the total number of individual animals or plants present. An analysis of historical and contemporary data on endemic whitefish from 17 large European lakes that experienced major diversity loss demonstrates the second mechanism in action. There is strong evidence to suggest that eutrophication, the biological enrichment of a lake over time, has driven the extinction of many endemic species by reversing ecological speciation. Such extinctions can be prevented only if conservation efforts, in addition to preserving existing species, identify and protect the processes that generate species.

Biological invasions are a principal threat to global biodiversity. Omnivores, such as crayfish, are among the most important groups of invaders. Their introduction often results in biodiversity loss, particularly of their native counterparts. Managed relocations of native crayfish from areas under threat from invasive crayfish into isolated 'ark sites' are sometimes suggested as a conservation strategy for native crayfish; however, such relocations may have unintended detrimental consequences for the recipient ecosystem. Despite this, there have been few attempts to quantify the relative impacts of native and invasive crayfish on aquatic ecosystems. To address this deficiency we conducted a meta-analysis on the effects of native and invasive crayfish on nine ecosystem components: decomposition rate, primary productivity, plant biomass, invertebrate density, biomass and diversity, fish biomass and refuge use, and amphibian larval survival. Native and invasive crayfish significantly reduced invertebrate density and biomass, fish biomass and amphibian survival rate and significantly increased decomposition rates. Invasive crayfish also significantly reduced plant biomass and invertebrate diversity and increased primary productivity. These results show that native and invasive crayfish have wide-ranging impacts on aquatic ecosystems that may be exacerbated for invasive species. Subsequent analysis showed that the impacts of invasive crayfish were significantly greater, in comparison to native crayfish, for decomposition and primary productivity but not invertebrate density, biomass and diversity. Overall, our findings reconfirm the ecosystem altering abilities of both native and invasive crayfish, enforcing the need to carefully regulate managed relocations of native species as well as to develop control programs for invasives.

Our previous experiments demonstrated that systemic depletion of serotonin (5-hydroxytryptamine, 5-HT), similar to levels reported in patients with emotional disorders, enhanced glutamateric activity in the lateral nucleus of the amygdala (LA) and potentiated fear behaviors. However, the effects of isolated depletion of 5-HT in the LA, and the molecular mechanisms underlying enhanced glutamatergic activity are unknown. In the present study, we tested the hypothesis that depletion of 5-HT in the LA induces increased fear behavior, and concomitantly enhances glutamate receptor (GluR) expression. Bilateral infusions of 5,7-dihydroxytryptamine (4 μg per side) into the LA produced a regional reduction of serotonergic fibers, resulting in decreased 5-HT concentrations. The induction of low 5-HT in the LA elevated fear-potentiated startle, with a parallel increase in GluR1 mRNA and GluR1 protein expression. These findings suggest that low 5-HT concentrations in the LA may facilitate fear behavior through enhanced GluR-mediated mechanisms. Moreover, our data support a relationship between 5-HT and glutamate in psychopathologies.

Much of the P in corn (Zea mays L.) grain is present in the form of phytic acid. Phytic acid P is unavailable to monogastric animals with most being excreted in the waste. As a result, the substantial P stores in grain are essentially wasted and may contribute to water pollution rather than animal productivity. The initial goal of this research was to isolate chemically induced mutants with reduced levels of phytic acid P in corn. Such mutants, referred to as low phytic acid or Ipa, were isolated and were found to have little or no other effect on kernel composition including no effect on total grain P content. The first mutant characterized, Ipal‐1, a 65% reduction in phytic acid and is accompanied by a molar‐equivalent increase in inorganic P. This mutant was backcrossed into elite corn inbred lines and resulting hybrids were evaluated for yield and other important agronomic traits. Preliminary field trials indicated germination, stalk strength, grain moisture at harvest, and flowering date were not affected by Ipal‐1. Some, but not all, Ipal‐1 hybrids had yield reductions. In a preliminary chick feeding trial, the low phytic acid grain resulted in greater P availability and reduced P content in the waste. Altering the phytic acid content genetically in corn is possible and may have the potential to improve feeding efficiencies and reduce P released to the environment.

Phytic acid (myo-inositol-1, 2, 3, 4, 5, 6-hexakisphosphate or Ins P6) typically represents approximately 75% to 80% of maize (Zea mays) seed total P. Here we describe the origin, inheritance, and seed phenotype of two non-lethal maize low phytic acid mutants, lpa1-1 and lpa2-1. The loci map to two sites on chromosome 1S. Seed phytic acid P is reduced in these mutants by 50% to 66% but seed total P is unaltered. The decrease in phytic acid P in mature lpa1-1 seeds is accompanied by a corresponding increase in inorganic phosphate (Pi). In mature lpa2-1 seed it is accompanied by increases in Pi and at least three other myo-inositol (Ins) phosphates (and/or their respective enantiomers): D-Ins(1,2,4,5,6) P5; D-Ins (1,4,5,6) P4; and D-Ins(1,2,6) P3. In both cases the sum of seed Pi and Ins phosphates (including phytic acid) is constant and similar to that observed in normal seeds. In both mutants P chemistry appears to be perturbed throughout seed development. Homozygosity for either mutant results in a seed dry weight loss, ranging from 4% to 23%. These results indicate that phytic acid metabolism during seed development is not solely responsible for P homeostasis and indicate that the phytic acid concentration typical of a normal maize seed is not essential to seed function.

Objective The objective of this paper is to examine whether smoking is associated with autoantibody production in systemic lupus erythematosus (SLE) patients, unaffected first-degree relatives (FDR) of individuals with SLE—a group at increased risk of developing SLE—or unaffected, unrelated controls. Methods Detailed demographic, environmental, clinical, and therapeutic information was collected by questionnaire on 1242 SLE patients, 981 FDRs, and 946 controls in the Lupus Family Registry and Repository; a blood sample was obtained. All sera were tested for multiple lupus autoantibodies by immunofluorescence and luminex bead-based assays. Generalized estimating equations, adjusting for age, gender, and ethnicity and accounting for correlation within families, were used to assess smoking status with the dichotomous outcome variables of positivity for SLE status, positivity of ANA by immunofluorescence (≥1:120), positivity for ≥1 autoantibody by the luminex assay, and positivity for each of the 11 autoantibodies. Results Current smoking was associated with being positive for ≥1 autoantibody (excluding ANA) (adjusted OR = 1.53, 95% CI 1.04-2.24) in our subjects with SLE. No association was observed in unaffected FDRs or healthy controls. Former smoking was associated with anti-Ro/SS-A60 in our unaffected FDRs. There was an increased association with anti-nRNP A seropositivity, as well as a decreased association with anti-nRNP 68 positivity, in current smokers in SLE subjects. Conclusions No clear association between smoking status and individual autoantibodies was detected in SLE patients, unaffected FDRs, nor healthy controls within this collection. The association of smoking with SLE may therefore manifest its risk through mechanisms outside of autoantibody production, at least for the specificities tested.

This study describes the inheritance and linkage map positions of two low phytic acid barley (Hordeum vulgare) mutations, lpal-1 and lpa2-1, that dramatically reduce grain phytic acid content and increase inorganic seed phosphorus (P). Wide-cross, [F.sub.2] mapping populations were constructed by mating six-rowed varieties, 'Steptoe' and/or 'Morex', with two-rowed 'Harrington' lpa donor lines homozygous for either lpa1-1 or lpa2-1. The barley lpa1-1 mutation showed normal inheritance patterns, whereas a deficiency of homozygous lpa2-1/lpa2-1 [F.sub.2] plants was observed. We identified a codominant, STS-PCR marker (aMSU21) that cosegregated with lpa1-1 in a population of 41 [F.sub.2] plants. The aMSU21 marker was then mapped to a locus on barley chromosome 2H, using a North American Barley Genome Mapping Project (NABGMP) doubled haploid population ('Harrington' x 'Morex'). We determined that lpa2-1 is located within a recombination interval of approximately 30 cM between two AFLP markers that were subsequently mapped to barley chromosome 7H by integration with the same NABGMP population. Recent comparative mapping studies indicate conserved genetic map orders of several homologous molecular marker loci in maize and the Triticeae species that also show corresponding linkage to the biochemically similar lpa2 mutations of maize and barley. This observation suggests that barley and maize lpa2 mutations may affect orthologous genes. No such evidence for correspondence of the phenotypically similar lpa1 mutations of barley and maize has been revealed.

This paper investigates multiple modeling choices for analyzing the rich and complex dynamics of high-speed milling processes. Various models are introduced to capture the effects of asymmetric structural modes and the influence of nonlinear regeneration in a discontinuous cutting force model. Stability is determined from the development of a dynamic map for the resulting variational system. The general case of asymmetric structural elements is investigated with a fixed frame and rotating frame model to show differences in the predicted unstable regions due to parametric excitation. Analytical and numerical investigations are confirmed through a series of experimental cutting tests. The principal results are additional unstable regions, hysteresis in the bifurcation diagrams, and the presence of coexisting periodic and quasiperiodic attractors which is confirmed through experimentation.

Recently, the development of ultrasonography (US)-guided vacuum-assisted breast biopsy (VABB) has enabled the excision of benign breast tumors with normal surrounding breast tissues; thus, complete excision is possible without residual tumor tissue. We sought to identify the clinicopathological characteristics and recurrence rates of benign phyllodes tumors diagnosed by US-guided VABB. Data from 11,221 US-guided VABBs performed at the Gangnam Cha Medical Center over 12 years were analyzed. Eighty-three lesions were diagnosed as benign phyllodes tumors; 67 with >24 months of follow-up data were investigated. All lesions were excised using an 8-gauge probe without residual tissue; patients underwent follow-up US every 3-6 months. Five patients (7.46%) experienced local recurrence during a mean follow-up period of 27.8 months; no distant metastases occurred. The mean tumor size was 3.0 cm in the recurrence group and 1.87 cm in the non-recurrence group (p=0.05). Benign phyllodes tumors excised and diagnosed using VABB showed a low recurrence rate during the follow-up period; thus, these tumors, particularly those <3 cm, can be safely monitored with ultrasonography instead of performing immediate re-excision.

Grains produced by low-phytate barley and corn isolines homozygous for each species' respective low phytic acid 1-1 allele were compared to grain produced by near-isogenic normal or wild-type barley and corn in broiler chick feeds. Cobb x Cobb (384) chicks were used in a 10-d study. A randomized complete block design with a factorial arrangement of 2 x 2 x 3 was used with 4 replicates (8 chicks / replicate) per treatment. Twelve isocaloric and isonitrogenous treatment diets were formulated to contain 2 types of grain (barley and corn), 2 levels of grain (40% and 60%), and 3 sources of available P (wild-type grain, wild-type P-supplemented grain, and low-phytate grain). Growth parameters, bone parameters, total bone mineral, and apparent digestibilities were measured. The mean growth and bone responses were 1) higher for barley diets compared to corn diets, 2) higher for 60% grain inclusion compared to 40%, 3) higher for low-phytate compared to wild-type grains, and 4) not different for low-phytate compared to P-supplemented wild-type grain diets. Chicks fed low-phytate-based diets excreted 33 and 43% less P than chicks fed wild-type and P-supplemented wild-type diets, respectively. Correlations between percentage bone ash, total bone ash, and bone strength indicated a strong relationship and appear to support the use of bone strength analysis as a simpler method than ash content determination as an indication of P status. Feeding low-phytate grains will reduce the need for supplemental P in chick diets.