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https://www.readbyqxmd.com/read/28732049/testing-the-optimal-defense-hypothesis-in-nature-variation-for-glucosinolate-profiles-within-plants
#1
Rose A Keith, Thomas Mitchell-Olds
Plants employ highly variable chemical defenses against a broad community of herbivores, which vary in their susceptibilities to specific compounds. Variation in chemical defenses within the plant has been found in many species; the ecological and evolutionary influences on this variation, however, are less well-understood. One central theory describing the allocation of defenses in the plant is the Optimal Defense Hypothesis (ODH), which predicts that defenses will be concentrated in tissues that are of high fitness value to the plant...
2017: PloS One
https://www.readbyqxmd.com/read/28731830/convergence-and-divergence-in-a-long-term-experiment-with-bacteria
#2
Richard E Lenski
Suitably designed experiments offer the possibility of quantifying evolutionary convergence because the fraction of replicate populations that converge is known. Here I review an experiment with Escherichia coli, in which 12 populations were founded from the same ancestral strain and have evolved for almost 30 years and more than 65,000 generations under the same conditions. The tension between divergence and convergence has been a major focus of this experiment. I summarize analyses of competitive fitness, correlated responses to different environments, cell morphology, the capacity to use a previously untapped resource, mutation rates, genomic changes, and within-population polymorphisms...
August 2017: American Naturalist
https://www.readbyqxmd.com/read/28731794/a-neutral-model-for-the-evolution-of-diet-breadth
#3
Matthew L Forister, Stephen H Jenkins
Variation in diet breadth among organisms is a pervasive feature of the natural world that has resisted general explanation. In particular, trade-offs in the ability to use one resource at the expense of another have been expected but rarely detected. We explore a spatial model for the evolution of specialization, motivated by studies of plant-feeding insects. The model is neutral with respect to the causes and consequences of diet breadth: the number of hosts utilized is not constrained by trade-offs, and specialization or generalization does not confer a direct advantage with respect to the persistence of populations or the probability of diversification...
August 2017: American Naturalist
https://www.readbyqxmd.com/read/28731545/genome-scale-data-reveals-that-endemic-poecilia-populations-from-small-sulfidic-springs-display-no-evidence-of-inbreeding
#4
Anthony P Brown, Ryan Greenway, Samuel Morgan, Corey R Quackenbush, Luca Giordani, Lenin Arias-Rodriguez, Michael Tobler, Joanna L Kelley
Populations with limited ranges can be highly vulnerable to changes in their environment and are, thus, of high conservation concern. Populations that experience human-induced range reductions are often highly inbred and lack genetic diversity, but it is unknown whether this is also the case for populations with naturally small ranges. The fishes Poecilia sulphuraria (listed as critically endangered) and Poecilia thermalis, which are endemic to small hydrogen sulfide rich springs in southern Mexico, are examples of such populations with inherently small habitats...
July 21, 2017: Molecular Ecology
https://www.readbyqxmd.com/read/28731472/high-abundance-and-expression-of-transposases-in-bacteria-from-the-baltic-sea
#5
Theoden Vigil-Stenman, Karolina Ininbergs, Birgitta Bergman, Martin Ekman
Transposases are mobile genetic elements suggested to have an important role in bacterial genome plasticity and host adaptation but their transcriptional activity in natural bacterial communities is largely unexplored. Here we analyzed metagenomes and -transcriptomes of size fractionated (0.1-0.8, 0.8-3.0 and 3.0-200 μm) bacterial communities from the brackish Baltic Sea, and adjacent marine waters. The Baltic Sea transposase levels, up to 1.7% of bacterial genes and 2% of bacterial transcripts, were considerably higher than in marine waters and similar to levels reported for extreme environments...
July 21, 2017: ISME Journal
https://www.readbyqxmd.com/read/28731216/indigenous-food-ingredients-for-complementary-food-formulations-to-combat-infant-malnutrition-in-benin-a-review
#6
REVIEW
Flora J Chadare, Yann E Madode, Nadia Fanou-Fogny, Janvier M Kindossi, Juvencio O Ayosso, Hermann S Honfo, Polycarpe Kayode, Anita R Linnemann, Joseph D Hounhouigan
This paper reviews indigenous Beninese food resources as potential ingredients for complementary infant foods with the aim to develop affordable formulations for low-income households in each agro-ecological zone of the country. Potential ingredients were selected on their documented nutritional value. The selected foods encompass 347 food resources, namely 297 plant products from home gardens or collected from natural vegetation and 50 animals, either domesticated or from the wild. The compiled data reveal that the distribution of the available food resources was unbalanced between agro-ecological zones...
July 21, 2017: Journal of the Science of Food and Agriculture
https://www.readbyqxmd.com/read/28730356/seasonal-variation-of-chemical-composition-and-source-apportionment-of-pm2-5-in-pune-india
#7
Ranjeeta D Gawhane, Pasumarthi Surya Prakasa Rao, Krishnakant B Budhavant, Vinayak Waghmare, Dhananjay C Meshram, Pramod D Safai
Particulate matter with size less than or equal to 2.5 μm (PM2.5) samples were collected from an urban site Pune, India, during April 2015 to April 2016. The samples were analyzed for various chemical constituents, including water soluble inorganic ions, organic carbon (OC), and elemental carbon (EC). The yearly mean total mass concentration of PM2.5 at Pune was 37.3 μg/m(3), which is almost four times higher than the annual WHO standard (10 μg/m(3)), and almost equal to that recommended by the Central Pollution Control Board, India (40 μg/m(3))...
July 20, 2017: Environmental Science and Pollution Research International
https://www.readbyqxmd.com/read/28730198/programming-shape-and-tailoring-transport-advancing-hygromorphic-bilayers-with-aligned-nanofibers
#8
S L M Alexander, S Ahmadmehrabi, L T J Korley
Natural systems utilize nanofiber architectures to guide water transport, tune mechanical properties, and actuate in response to their environment. In order to harness these properties, a hygromorphic bilayer composite comprised of a self-assembled fiber network and an aligned electrospun fiber network was fabricated. Molecular gel self-assembly was utilized to increase hydrophobicity and strength in one layer, while aligned electrospun poly(vinyl alcohol) (PVA) nanofibers increased the rate of hydration and facilitated tunable actuation in the other...
July 21, 2017: Soft Matter
https://www.readbyqxmd.com/read/28729795/cone-beam-computed-tomographic-evaluation-of-styloid-process-a-retrospective-study-of-1000-patients
#9
Merve Donmez, Ozlem Okumus, Filiz Namdar Pekiner
OBJECTIVE: The styloid process (SP) is a bony projection, located just anterior to the stylomastoid foramen, the normal length of which is approximately 20-30 mm. The length of SP when exceeds 30 mm it is said to "elongated." The purpose of this retrospective study was to assess the prevalence of elongated SP (ESP) by cone beam computed tomography (CBCT) examination in Turkish subpopulation and its relation to gender and age. MATERIALS AND METHODS: This study analyzed CBCT of 1000 patients who were randomly selected to participate and were aged from 14 to 78 years...
April 2017: European Journal of Dentistry
https://www.readbyqxmd.com/read/28729732/evidence-of-selection-on-splicing-associated-loci-in-human-populations-and-relevance-to-disease-loci-mapping
#10
Eric R Gamazon, Anuar Konkashbaev, Eske M Derks, Nancy J Cox, Younghee Lee
We performed a whole-genome scan of genetic variants in splicing regulatory elements (SREs) and evaluated the extent to which natural selection has shaped extant patterns of variation in SREs. We investigated the degree of differentiation of single nucleotide polymorphisms (SNPs) in SREs among human populations and applied long-range haplotype- and multilocus allelic differentiation-based methods to detect selection signatures. We describe an approach, sampling a large number of loci across the genome from functional classes and using the consensus from multiple tests, for identifying candidates for selection signals...
July 20, 2017: Scientific Reports
https://www.readbyqxmd.com/read/28729609/maternally-transmitted-microbiota-affects-odor-emission-and-preference-in-drosophila-larva
#11
Jean-Pierre Farine, Wafa Habbachi, Jérôme Cortot, Suzy Roche, Jean-François Ferveur
Experimental studies show that early sensory experience often affects subsequent sensory preference, suggesting that the heterogeneity of sensory cues in nature could induce significant inter-individual behavioral variation, potentially contributing to maintain intraspecific diversity. To test this hypothesis, we explored the behavioral effect induced by variation in the levels of a self-produced chemical, acetoin, and its link with intraspecific diversity. Acetoin is a pheromone-like substance produced by gut-associated microorganisms in Drosophila...
July 20, 2017: Scientific Reports
https://www.readbyqxmd.com/read/28729404/exploiting-natural-variation-to-uncover-an-alkene-biosynthetic-enzyme-in-poplar
#12
Eliana Gonzales-Vigil, Charles A Hefer, Michelle E von Loessl, Jonathan La Mantia, Shawn D Mansfield
Alkenes are linear hydrocarbons with one or more double bonds. Despite their potential as biofuels and precursors for specialty chemicals, the underlying biochemistry and genetics of alkene biosynthesis in plants remain elusive. Here, we report on a screen of natural accessions of poplar (Populus trichocarpa) revealing that the leaf cuticular waxes are predominantly composed of alkanes and alkenes. Interestingly, the accumulation of alkenes increases with leaf development, is limited to the abaxial side of the leaf, and is impaired in a few accessions...
July 20, 2017: Plant Cell
https://www.readbyqxmd.com/read/28727232/functional-genomic-analysis-of-corals-from-natural-co2-seeps-reveals-core-molecular-responses-involved-in-acclimatization-to-ocean-acidification
#13
C D Kenkel, A Moya, J Strahl, C Humphrey, L K Bay
Little is known about the potential for acclimatization or adaptation of corals to ocean acidification and even less about the molecular mechanisms underpinning these processes. Here we examine global gene expression patterns in corals and their intracellular algal symbionts from two replicate population pairs in Papua New Guinea that have undergone long-term acclimatization to natural variation in pCO2 . In the coral host, only 61 genes were differentially expressed in response to pCO2 environment, but the pattern of change was highly consistent between replicate populations, likely reflecting the core expression homeostasis response to ocean acidification...
July 20, 2017: Global Change Biology
https://www.readbyqxmd.com/read/28726571/primary-blast-causes-delayed-effects-without-cell-death-in-shell-encased-brain-cell-aggregates
#14
Thomas Sawyer, Yushan Wang, David V Ritzel, Tyson Josey, Mercy Villanueva, Cory Vair, Yanfeng Song, Yimin Shei, Steven Parks, Peggy Nelson, Grant Hennes, Lori McLaws, Changyan Fan
Previous work used underwater explosive exposures to isolate the effects of shock-induced principle stress without shear on rat brain aggregate cultures. This current study has utilized simulated air blast to expose aggregates in suspension and enclosed within a spherical shell, enabling the examination of a much more complex biomechanical insult. Culture medium-filled spheres were exposed to single pulse overpressures of 15-30 psi (6-7 msec duration) and measurements within the sphere at defined sites showed complex and spatially dependent pressure changes...
July 20, 2017: Journal of Neurotrauma
https://www.readbyqxmd.com/read/28725990/molecular-characterization-of-the-indigenous-stingless-bees-tetragonula-spp-complex-using-issr-marker-from-southern-peninsular-india
#15
P P Nayak, J Prakash
India is a country bestowed enormously with stingless bees, but genetic information about them is extremely minimal. This study focused to tap the geographic allocation, genetic variability, and differentiation among Tetragonula species complexes from natural and semi-urban habitats. Genetic analyses were assessed among 36 contrasting genotypes utilizing 20 ISSR primers. The dual combination exquisitely and productively amplified 245 DNA fragments at the loci, of which 240 bands were polymorphic (97.95%). Low to moderate level of genetic differentiation was detected from different estimators (Ht 0...
July 19, 2017: Neotropical Entomology
https://www.readbyqxmd.com/read/28725552/repeated-inoculations-with-the-lung-and-heartworm-nematode-angiostrongylus-vasorum-result-in-increasing-larval-excretion-and-worm-burden-in-the-red-fox-vulpes-vulpes
#16
Ian David Woolsey, P Webster, S Thamsborg, Manuela Schnyder, Jesper Monrad, C M O Kapel
The French heartworm Angiostongylus vasorum is found in European red fox (Vulpes vulpes) and dog populations, where it appears to be spreading geographically. Once introduced into new areas, it establishes in local fox populations, typically to over 50% prevalence in a few years. High susceptibility and constant excretion of first stage larvae (L1) by the definitive hosts are prerequisites for sustaining high parasite biomass in a particular habitat. The present study explores the hypothesis that repeated ingestion of gastropods in nature will result in accumulation of adult worms and elevated excretion of L1 in feces...
December 2017: International Journal for Parasitology. Parasites and Wildlife
https://www.readbyqxmd.com/read/28725411/choosing-a-mate-in-a-high-predation-environment-female-preference-in-the-fiddler-crab-uca-terpsichores
#17
Daniela M Perez, John H Christy, Patricia R Y Backwell
The interplay between a receiver's sensory system and a sender's courtship signals is fundamental to the operation of sexual selection. Male courtship signals that match a female receiver's preexisting perceptual biases can be favored yet the message they communicate is not always clear. Do they simply beacon the male's location or also indicate his quality? We explored this question in a species of fiddler crab Uca terpsichores that courts under elevated predation risk and that mates and breeds underground in the safety of males' burrows...
October 2016: Ecology and Evolution
https://www.readbyqxmd.com/read/28725403/potential-and-limitations-of-inferring-ecosystem-photosynthetic-capacity-from-leaf-functional-traits
#18
Talie Musavi, Mirco Migliavacca, Martine Janet van de Weg, Jens Kattge, Georg Wohlfahrt, Peter M van Bodegom, Markus Reichstein, Michael Bahn, Arnaud Carrara, Tomas F Domingues, Michael Gavazzi, Damiano Gianelle, Cristina Gimeno, André Granier, Carsten Gruening, Kateřina Havránková, Mathias Herbst, Charmaine Hrynkiw, Aram Kalhori, Thomas Kaminski, Katja Klumpp, Pasi Kolari, Bernard Longdoz, Stefano Minerbi, Leonardo Montagnani, Eddy Moors, Walter C Oechel, Peter B Reich, Shani Rohatyn, Alessandra Rossi, Eyal Rotenberg, Andrej Varlagin, Matthew Wilkinson, Christian Wirth, Miguel D Mahecha
The aim of this study was to systematically analyze the potential and limitations of using plant functional trait observations from global databases versus in situ data to improve our understanding of vegetation impacts on ecosystem functional properties (EFPs). Using ecosystem photosynthetic capacity as an example, we first provide an objective approach to derive robust EFP estimates from gross primary productivity (GPP) obtained from eddy covariance flux measurements. Second, we investigate the impact of synchronizing EFPs and plant functional traits in time and space to evaluate their relationships, and the extent to which we can benefit from global plant trait databases to explain the variability of ecosystem photosynthetic capacity...
October 2016: Ecology and Evolution
https://www.readbyqxmd.com/read/28725402/what-does-body-size-mean-from-the-plant-s-eye-view
#19
Amanda J Tracey, Kimberly A Stephens, Brandon S Schamp, Lonnie W Aarssen
Alternative metrics exist for representing variation in plant body size, but the vast majority of previous research for herbaceous plants has focused on dry mass. Dry mass provides a reasonably accurate and easily measured estimate for comparing relative capacity to convert solar energy into stored carbon. However, from a "plant's eye view", its experience of its local biotic environment of immediate neighbors (especially when crowded) may be more accurately represented by measures of "space occupancy" (S-O) recorded in situ-rather than dry mass measured after storage in a drying oven...
October 2016: Ecology and Evolution
https://www.readbyqxmd.com/read/28725150/development-and-evaluation-of-ketoprofen-sustained-release-matrix-tablet-using-hibiscus-rosa-sinensis-leaves-mucilage
#20
M Kaleemullah, K Jiyauddin, E Thiban, S Rasha, S Al-Dhalli, S Budiasih, O E Gamal, A Fadli, Y Eddy
Currently, the use of natural gums and mucilage is of increasing importance in pharmaceutical formulations as valuable drug excipient. Natural plant-based materials are economic, free of side effects, biocompatible and biodegradable. Therefore, Ketoprofen matrix tablets were formulated by employing Hibiscus rosa-sinensis leaves mucilage as natural polymer and HPMC (K100M) as a synthetic polymer to sustain the drug release from matrix system. Direct compression method was used to develop sustained released matrix tablets...
July 2017: Saudi Pharmaceutical Journal: SPJ: the Official Publication of the Saudi Pharmaceutical Society
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