Keeping the blood flowing—plasminogen activator genes and feeding behavior in vampire bats

The blood feeding vampire bats emerged from New World leaf-nosed bats that fed on fruit and insects. Plasminogen activator, a serine protease that regulates blood coagulation, is known to be expressed in the saliva of Desmodus rotundus (common vampire bat) and is thought to be a key enzyme for the emergence of blood feeding in vampire bats. To better understand the evolution of this biological function, we studied the plasminogen activator (PA) genes from all vampire bat species in light of their feeding transition to bird and subsequently mammalian blood. We include the rare species Diphylla ecaudata and Diaemus youngi, where plasminogen activator had not previously been studied and demonstrate that PA gene duplication observed in Desmodus is not essential to the vampire phenotype, but relates to the emergence of predominant mammalian blood feeding in this species. Plasminogen activator has evolved through gene duplication, domain loss, and sequence evolution leading to change in fibrin-specificity and susceptibility to plasminogen activator inhibitor-1. Before undertaking this study, only the four plasminogen activator isoforms from Desmodus were known. The evolution of vampire bat plasminogen activators can now be linked phylogenetically to the transition in feeding behavior among vampire bat species from bird to mammalian blood. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users.     

Runoff and dissolved organic carbon loss from a paired-watershed study of three adjacent agricultural Watersheds

Organic matter plays several important roles in the biogeochemistry of terrestrial and aquatic ecosystems including the mobilization and transport of nutrients and pollutants. Cropping, tillage practices and vegetative buffer strip installation affect losses of dissolved organic carbon (DOC). While many studies show reductions in pollutant export from agroecosystems where vegetative buffers have been implemented, buffer strips may be a source of DOC and contribute to surface water pollution. Using a paired-watershed approach, the objectives of this study were to determine the effect of grass and agroforestry buffers on runoff and DOC loss, compare runoff and DOC losses between the growing and fallow seasons, and investigate crop effects on runoff and DOC losses. The study design consisted of three small agricultural Watersheds in a no-till, maize-soybean rotation located in the claypan region of northeast Missouri, USA; one watershed was planted with grass buffer strips, one with agroforestry buffer strips, and one unaltered watershed served as the control. Runoff and DOC loss were measured during a six-year calibration period (1991–1997) prior to buffer installation and for a nine-year treatment period (1997–2006). The grass buffer strips significantly decreased runoff by 8.4% (p = 0.015) during the treatment period while the agroforestry buffer system exhibited no significant change in runoff (p = 0.207). Loss of DOC was not significantly affected by grass or agroforestry buffer installation (p = 0.535 and p = 0.246, respectively). Additionally, no significant difference in runoff or DOC loss was found between crops (maize and soybean) or between seasons (growing and fallow). Overall, this study indicates that grass buffer systems are effective at reducing runoff and that DOC contamination of surface waters is not exacerbated by either type of vegetative buffer strip.     

Sex or Food? Appetetive Learning of Sex Odors in a Male Moth

Moths learn to associate a flower odor with a food reward after a few learning trials. Can a hungry, male moth learn to associate a sex attractant with food instead of with sex? We provided a hungry male with odors of single female sex pheromone components, of the full sex pheromone blend or of a flower odor component as cues in an appetitive learning assay. The male learned the single pheromone components just as well as the flower odor. Learning was, however, severely impaired when the full sex pheromone blend was used as conditioning stimulus. The "hard-wiring" between pheromone odor and sex thus seems to be restricted to those circumstances when the male moth experiences the full blend.     

Synthesis of zinc-carboxylate metal-organic frameworks for the removal of emerging drug contaminant (amodiaquine) from aqueous solution

We herein report the removal of amodiaquine, an emerging drug contaminant from aqueous solution using [Zn2(fum)2(bpy)] and [Zn4 O(bdc)3](fum = fumaric acid; bpy =4,4-bipyridine; bdc = benzene-1,4-dicarboxylate) metal–organic frameworks(MOFs) as adsorbents. The adsorbents were characterized by elemental analysis, Fourier transform infrared(FT-IR) spectroscopy, and powder X-ray diffraction(PXRD). Adsorption process for both adsorbents were found to follow the pseudo-first-order kinetics, and the adsorption equilibrium data fitted best into the Freundlich isotherm with the R~2 values of 0.973 and0.993 obtained for [Zn_2(fum)_2(bpy)] and [Zn_4 O(bdc)_3] respectively. The maximum adsorption capacities foramodiaquine in this study were found to be 0.478 and 47.62 mg/g on the[Zn_2(fum)_2(bpy)] and [Zn_4 O(bdc)_3] MOFs respectively, and were obtained at p H of 4.3 for both adsorbents. FT-IR spectroscopy analysis of the MOFs after the adsorption process showed the presence of the drug. The results of the study showed that the prepared MOFs could be used for the removal of amodiaquine from wastewater.     

Millennium-old farm breeding of Chinese softshell turtles (<Emphasis Type="Italic">Pelodiscus</Emphasis> spp.) results in massive erosion of biodiversity

Chinese softshell turtles (Pelodiscus spp.) are widely distributed, ranging from the Amur and Ussuri Rivers in the Russian Far East through the Korean Peninsula, Japan, and eastern, central, and southern China to southern Vietnam. In East and Southeast Asia, Chinese softshell turtles are traditionally exploited for food and have been farm-bred in China since the Spring and Autumn Period, more than 2400 years ago. Currently, the annual production of Pelodiscus amounts to 340,000 t in China alone. Using mitochondrial DNA (2428 bp) and five nuclear loci (3704 bp), we examined broad sampling of wild and farm-bred Pelodiscus to infer genetic and taxonomic differentiation. We discovered four previously unknown mitochondrial lineages, all from China. One lineage from Jiangxi is deeply divergent and sister to the mitochondrial lineage of Pelodiscus axenaria. The nuclear loci supported species status for P. axenaria and the new lineage from Jiangxi. Pelodiscus maackii and P. parviformis, both harboring distinct mitochondrial lineages, were not differentiated from P. sinensis in the studied nuclear markers. The same is true for two new mitochondrial lineages from Zhejiang, China, represented by only one individual each, and another new lineage from Anhui, Guangdong, Jiangxi and Zhejiang, China. However, Vietnamese turtles yielding a mitochondrial lineage clustering within P. sinensis were distinct in nuclear markers, suggesting that these populations could represent another unknown species with introgressed mitochondria. Its species status is also supported by the syntopic occurrence with P. sinensis in northern Vietnam and by morphology. In addition, we confirmed sympatry of P. axenaria and P. parviformis in Guangxi, China, and found evidence for sympatry of P. sinensis and the new putative species from Jiangxi, China. We also discovered evidence for hybridization in turtle farms and for the occurrence of alien lineages in the wild (Zhejiang, China), highlighting the risk of genetic pollution of native stock. In the face of the large-scale breeding of Pelodiscus, we claim that the long-term survival of distinct genetic lineages and species can only be assured when an upscale market segment for pure-bred softshell turtles is established, making the breeding of pure lineages lucrative for turtle farms. Our findings underline that the diversity of Pelodiscus is currently underestimated and threatened by anthropogenic admixture. We recommend mass screening of genetic and morphological variation of Chinese softshell turtles as a first step to understand and preserve their diversity.     

Major challenges of integrating agriculture into climate change mitigation policy frameworks

Taking the European Union (EU) as a case study, we simulate the application of non-uniform national mitigation targets to achieve a sectoral reduction in agricultural non-carbon dioxide (CO₂) greenhouse gas (GHG) emissions. Scenario results show substantial impacts on EU agricultural production, in particular, the livestock sector. Significant increases in imports and decreases in exports result in rather moderate domestic consumption impacts but induce production increases in non-EU countries that are associated with considerable emission leakage effects. The results underline four major challenges for the general integration of agriculture into national and global climate change mitigation policy frameworks and strategies, as they strengthen requests for (1) a targeted but flexible implementation of mitigation obligations at national and global level and (2) the need for a wider consideration of technological mitigation options. The results also indicate that a globally effective reduction in agricultural emissions requires (3) multilateral commitments for agriculture to limit emission leakage and may have to (4) consider options that tackle the reduction in GHG emissions from the consumption side.     

Mating System and Sexual Selection in the Scorpionfly Panorpa vulgaris (Mecoptera: Panorpidae)

Panorpa vulgaris   has become a model insect for testing theories of sexual selection. This contribution summarizes that which has been learned in recent years and presents new data that clearly show that the mating system of P. vulgaris is not simply a resource-defense polygyny, as has previously been thought. In P. vulgaris neither the pattern in food exploitation nor the ratio of variance in the lifetime reproductive success of the two sexes is in accordance with that expected in resource defense polygynous mating systems. Lifetime mating duration is the most important proximate determinant of male fitness. Males employing alternative mating tactics obtain copulations of varying duration in relation to the following sequence: saliva secretion  1  food offering  1  no gift. The number of salivary masses which males provide to females during their lifetime is significantly correlated with the lifetime condition index. The condition index depends on the fighting prowess of males and their ability to find food items. Thus saliva secretion of Panorpa is considered a Zahavian handicap, which can serve as an honest quality indicator used by mating females. Our results confirm four main predictions of the indicator model of the theory of sexual selection: (a) the indicator signals high ecological quality of its bearer, (b) the indicator value increases with phenotypic quality, (c) the indicator value is positively correlated with the genetic quality affecting offspring fitness in a natural selection context, and (d) the quality indicator is more costly for low- than for high-quality individuals. The evolutionary consequences of the mating pattern and the sperm competition mechanism in P. vulgaris are discussed in the context the way in which sexual selection creates and maintains sperm mixing and the evolution of a promiscuous mating system.     

Review of epidemiological factors (other than maternal age) that determine the prevalence of common autosomal trisomies

The birth prevalence of each common autosomal trisomy (21, 18 and 13) increases with advancing maternal age and this is the most important epidemiological risk factor. Prevalence during pregnancy is also dependent on gestational age. Other factors claimed to influence prevalence include paternal age, ethnicity, family history, premature reproductive aging, parity, twinning, smoking, environmental exposures, maternal medical conditions, and predispositions. We review the evidence for these associations since they may provide insights into causal mechanisms. When investigating potential co-factors it is important to adequately allow for maternal age and minimize its confounding contribution. This is well illustrated by reports of an inverse paternal age effect where there is strong correlation between parental ages. Gestational age at diagnosis, availability of prenatal screening, diagnostic testing, and elective termination of affected pregnancies and healthcare disparities also confound the studies on ethnicity, medical conditions, and predispositions or environmental factors. Data from twin zygosity studies demonstrate the importance of differences in fetal viability for affected pregnancies. We conclude that existing epidemiological evidence for most of the co-factors discussed should currently be considered tenuous; history of Down syndrome, albeit biased, may be an exception. The co-factors may yet provide clues to hitherto poorly understood causal pathways.