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https://www.readbyqxmd.com/read/28110272/mitonuclear-interactions-mediate-transcriptional-responses-to-hypoxia-in-drosophila
#1
Jim A Mossman, Jennifer G Tross, Nick A Jourjine, Nan Li, Zhijin Wu, David M Rand
Among the major challenges in quantitative genetics and personalized medicine is to understand how gene × gene interactions (G × G: epistasis) and gene × environment interactions (G × E) underlie phenotypic variation. Here, we use the intimate relationship between mitochondria and oxygen availability to dissect the roles of nuclear DNA (nDNA) variation, mitochondrial DNA (mtDNA) variation, hypoxia, and their interactions on gene expression in Drosophila melanogaster Mitochondria provide an important evolutionary and medical context for understanding G × G and G × E given their central role in integrating cellular signals...
November 14, 2016: Molecular Biology and Evolution
https://www.readbyqxmd.com/read/28109837/interspecific-variation-and-plasticity-in-hemoglobin-nitrite-reductase-activity-and-its-correlation-with-oxygen-affinity-in-vertebrates
#2
Frank B Jensen, Rasmus A H Kolind, Natashia S Jensen, Gabriella Montesanti, Tobias Wang
Deoxygenated hemoglobin (Hb) is a nitrite reductase that reduces naturally occurring nitrite to nitric oxide (NO), supplying physiological relevant NO under hypoxic conditions. The nitrite reductase activity is modulated by the allosteric equilibrium between the R and T structures of Hb that also determines oxygen affinity. In the present study we investigated nitrite reductase activity and O2 affinity in Hbs from ten different vertebrate species under identical conditions to disclose interspecific variations and allow an extended test for a correlation between the rate constant for nitrite reduction and O2 affinity...
January 18, 2017: Comparative Biochemistry and Physiology. Part A, Molecular & Integrative Physiology
https://www.readbyqxmd.com/read/28109654/spatial-and-temporal-variation-of-macro-meso-and-microplastic-abundance-on-a-remote-coral-island-of-the-maldives-indian-ocean
#3
Hannes K Imhof, Robert Sigl, Emilia Brauer, Sabine Feyl, Philipp Giesemann, Saskia Klink, Kathrin Leupolz, Martin G J Löder, Lena A Löschel, Jan Missun, Sarah Muszynski, Anja F R M Ramsperger, Isabella Schrank, Susan Speck, Sebastian Steibl, Benjamin Trotter, Isabel Winter, Christian Laforsch
Plastic debris is ubiquitous in the marine environment and the world's shores represent a major sink. However, knowledge about plastic abundance in remote areas is scarce. Therefore, plastic abundance was investigated on a small island of the Maldives. Plastic debris (>1mm) was sampled once in natural long-term accumulation zones at the north shore and at the high tide drift line of the south shore on seven consecutive days to quantify daily plastic accumulation. Reliable identification of plastic debris was ensured by FTIR spectroscopy...
January 18, 2017: Marine Pollution Bulletin
https://www.readbyqxmd.com/read/28109603/comparison-between-direct-and-indirect-methods-for-exploiting-fourier-transform-spectral-information-in-estimation-of-breeding-values-for-fine-composition-and-technological-properties-of-milk
#4
V Bonfatti, D Vicario, L Degano, A Lugo, P Carnier
The aim of this study was to compare the common method of exploiting infrared spectral data in animal breeding; that is, estimating the breeding values for the traits predicted by infrared spectroscopy, and an alternative approach based on the direct use of spectral information (direct prediction, DP) to predict the estimated breeding values (EBV). Traits were pH, milk coagulation properties, contents of the main casein and whey protein fractions, cheese yield measured by micro-cheese making, lactoferrin, Ca, and fat composition...
January 18, 2017: Journal of Dairy Science
https://www.readbyqxmd.com/read/28109305/medical-pluralism-and-livestock-health-ethnomedical-and-biomedical-veterinary-knowledge-among-east-african-agropastoralists
#5
Mark A Caudell, Marsha B Quinlan, Robert J Quinlan, Douglas R Call
BACKGROUND: Human and animal health are deeply intertwined in livestock dependent areas. Livestock health contributes to food security and can influence human health through the transmission of zoonotic diseases. In low-income countries diagnosis and treatment of livestock diseases is often carried out by household members who draw upon both ethnoveterinary medicine (EVM) and contemporary veterinary biomedicine (VB). Expertise in these knowledge bases, along with their coexistence, informs treatment and thus ultimately impacts animal and human health...
January 21, 2017: Journal of Ethnobiology and Ethnomedicine
https://www.readbyqxmd.com/read/28108840/differences-in-monoterpene-biosynthesis-and-accumulation-in-pistacia-palaestina-leaves-and-aphid-induced-galls
#6
Karin Rand, Einat Bar, Matan Ben Ari, Rachel Davidovich-Rikanati, Natalia Dudareva, Moshe Inbar, Efraim Lewinsohn
Certain insect species can induce gall formation on numerous plants species. Although the mechanism of gall development is largely unknown, it is clear that insects manipulate their hosts' anatomy, physiology, and chemistry for their own benefit. It is well known that insect-induced galls often contain vast amounts of plant defensive compounds as compared to non-colonized tissues, but it is not clear if defensive compounds can be produced in situ in the galled tissues. To answer this question, we analyzed terpene accumulation patterns and possible independent biosynthetic potential of galls induced by the aphid Baizongia pistaciae L...
January 20, 2017: Journal of Chemical Ecology
https://www.readbyqxmd.com/read/28108698/genome-wide-analysis-of-fatty-acid-desaturation-and-its-response-to-temperature
#7
Guillaume Menard, Jose Martin Moreno, Fiona Bryant, Olaya Munoz-Azcarate, Amélie A Kelly, Keywan Hassani-Pak, Smita Kurup, Peter J Eastmond
Plants modify the polyunsaturated fatty acid content of their membrane and storage lipids in order to adapt to changes in temperature. In developing seeds this response is largely controlled by the activities of the microsomal ω-6 and ω-3 fatty acid desaturases, FAD2 and FAD3. Although temperature-regulation of desaturation has been studied at the molecular and biochemical level, the genetic control of this trait is poorly understood. Here we have characterised the response of Arabidopsis thaliana seed lipids to variation in ambient temperature and found that heat inhibits both ω-6 and ω-3 desaturation in phosphatidylcholine, leading to a proportional change in triacylglycerol composition...
January 20, 2017: Plant Physiology
https://www.readbyqxmd.com/read/28107517/high-emigration-propensity-and-low-mortality-on-transfer-drives-female-biased-dispersal-of-pyriglena-leucoptera-in-fragmented-landscapes
#8
Marcelo Awade, Carlos Candia-Gallardo, Cintia Cornelius, Jean Paul Metzger
Dispersal is a biological process performed in three stages: emigration, transfer and immigration. Intra-specific variation on dispersal behavior, such as sex-bias, is very common in nature, particularly in birds and mammals. However, dispersal is difficult to measure in the field and many hypotheses concerning the causes of sex-biased dispersal remain without empirical confirmation. An important limitation of most empirical studies is that inferences about sex-biased dispersal are based only on emigration proneness or immigration success data...
2017: PloS One
https://www.readbyqxmd.com/read/28107414/multifractality-and-network-analysis-of-phase-transition
#9
Longfeng Zhao, Wei Li, Chunbin Yang, Jihui Han, Zhu Su, Yijiang Zou
Many models and real complex systems possess critical thresholds at which the systems shift dramatically from one sate to another. The discovery of early-warnings in the vicinity of critical points are of great importance to estimate how far the systems are away from the critical states. Multifractal Detrended Fluctuation analysis (MF-DFA) and visibility graph method have been employed to investigate the multifractal and geometrical properties of the magnetization time series of the two-dimensional Ising model...
2017: PloS One
https://www.readbyqxmd.com/read/28107227/structural-level-differences-in-the-mother-to-child-hiv-transmission-rate-in-south-africa-a-multilevel-assessment-of-individual-health-facility-and-provincial-level-predictors-of-infant-hiv-transmission
#10
S Woldesenbet, D J Jackson, C J Lombard, T H Dinh, V Ramokolo, T Doherty, G G Sherman, Y Pillay, A E Goga
OBJECTIVES: In 2010, South Africa reported an early mother to child transmission (MTCT) rate of 3.5% at 4-8 weeks postpartum. Provincial early MTCT rates ranged from 1.4% (95% confidence interval [CI]: 0.1-3.4%) to 5.9% (95% CI: 3.8-8.0%). We sought to determine reasons for these geographic differences in MTCT rates. METHODS: This study employed multilevel modelling using 2010 South African PMTCT evaluation (SAPMTCTE) data from 530 facilities. Interview data and infant blood samples were collected from 3085 mother-infant pairs at 4-8 weeks postpartum...
January 18, 2017: Journal of Acquired Immune Deficiency Syndromes: JAIDS
https://www.readbyqxmd.com/read/28107061/the-evolution-of-reproductive-phenology-in-broadcast-spawners-and-the-maintenance-of-sexually-antagonistic-polymorphism
#11
Colin Olito, Dustin J Marshall, Tim Connallon
Reproductive phenology is a crucial life-history trait that evolves in response to external environmental conditions and frequency- and density-dependent interactions within species. Broadcast spawners-which represent a large fraction of aquatic biodiversity-evolve phenologies that balance strong density-dependent fertilization success against abiotic environmental conditions that are required for successful reproduction. The overall balance between these processes may be particularly complex in dioecious species, where selection on reproductive timing potentially differs between the sexes...
February 2017: American Naturalist
https://www.readbyqxmd.com/read/28107035/determination-of-the-zinc-concentration-in-human-fingernails-using-laser-induced-breakdown-spectroscopy
#12
Vlora A Riberdy, Christopher J Frederickson, Steven J Rehse
The absolute concentration of Zn in human fingernail clippings was determined ex vivo using 1064 nm laser-induced breakdown spectroscopy and confirmed by speciated isotope dilution mass spectrometry. A nail testing protocol that sampled across the nail (perpendicular to the direction of growth) was developed and validated by scanning electron microscopy energy-dispersive X-ray spectrometry. Using this protocol, a partial least squares (PLS) regression model predicted the Zn concentration in the fingernails of five people to within an average of 7 ppm...
January 1, 2017: Applied Spectroscopy
https://www.readbyqxmd.com/read/28105843/adaptive-pcr-based-on-hybridization-sensing-of-mirror-image-l-dna
#13
Nicholas M Adams, William E Gabella, Austin N Hardcastle, Frederick R Haselton
Polymerase chain reaction (PCR) is dependent on two key hybridization events during each cycle of amplification, primer annealing and product melting. To ensure that these hybridization events occur, current PCR approaches rely on temperature set points and reaction contents that are optimized and maintained using rigid thermal cycling programs and stringent sample preparation procedures. This report describes a fundamentally simpler and more robust PCR design that dynamically controls thermal cycling by more directly monitoring the two key hybridization events during the reaction...
January 3, 2017: Analytical Chemistry
https://www.readbyqxmd.com/read/28104924/the-adaptive-nature-of-culture-a-cross-cultural-analysis-of-the-returns-of-local-environmental-knowledge-in-three-indigenous-societies
#14
Victoria Reyes-García, Maximilien Guèze, Isabel Díaz-Reviriego, Romain Duda, Álvaro Fernández-Llamazares, Sandrine Gallois, Lucentezza Napitupulu, Martí Orta-Martínez, Aili Pyhälä
Researchers have argued that the behavioral adaptations that explain the success of our species are partially cultural, i.e., cumulative and socially transmitted. Thus, understanding the adaptive nature of culture is crucial to understand human evolution. We use a cross-cultural framework and empirical data purposely collected to test whether culturally transmitted and individually appropriated knowledge provides individual returns in terms of hunting yields and health and, by extension, to nutritional status, a proxy for individual adaptive success...
December 2016: Current Anthropology
https://www.readbyqxmd.com/read/28104347/bacterial-resistance-to-antibodies-a-model-evolutionary-study
#15
Lawrence S Schulman
The tangled nature model of evolution (reviewed in the main text) is adapted for use in the study of antibody resistance acquired by horizontal gene transfer. Exchanges of DNA and the acquisition of resistant gene sequences are considered. For the parameters used, resistant strains rapidly proliferate and dominate, although initial intense antibiotic treatment can occasionally prevent this. Variation in genome distribution appears to be long tailed. If this is reflected in nature, the occurrence of resistant bacterial strains can be expected, as well as considerable variation in patient outcomes...
January 16, 2017: Journal of Theoretical Biology
https://www.readbyqxmd.com/read/28103794/genomic-and-transcriptomic-comparison-between-staphylococcus-aureus-strains-associated-with-high-and-low-within-herd-prevalence-of-intra-mammary-infection
#16
E Capra, P Cremonesi, A Pietrelli, S Puccio, M Luini, A Stella, B Castiglioni
BACKGROUND: Staphylococcus aureus (Staph. aureus) is one of the major pathogens causing mastitis in dairy ruminants worldwide. The chronic nature of Staph. aureus infection enhances the contagiousness risk and diffusion in herds. In order to identify the factors involved in intra-mammary infection (IMI) and diffusion in dairy cows, we investigated the molecular characteristics of two groups of Staph. aureus strains belonging to ST8 and ST398, differing in clinical properties, through comparison of whole genome and whole transcriptome sequencing...
January 19, 2017: BMC Microbiology
https://www.readbyqxmd.com/read/28103190/learning-supervised-topic-models-for-classification-and-regression-from-crowds
#17
Filipe Rodrigues, Mariana Lourenco, Bernardete Ribeiro, Francisco Pereira
The growing need to analyze large collections of documents has led to great developments in topic modeling. Since documents are frequently associated with other related variables, such as labels or ratings, much interest has been placed on supervised topic models. However, the nature of most annotation tasks, prone to ambiguity and noise, often with high volumes of documents, deem learning under a single-annotator assumption unrealistic or unpractical for most real-world applications. In this article, we propose two supervised topic models, one for classification and another for regression problems, which account for the heterogeneity and biases among different annotators that are encountered in practice when learning from crowds...
January 5, 2017: IEEE Transactions on Pattern Analysis and Machine Intelligence
https://www.readbyqxmd.com/read/28102915/transgenerational-effects-alter-plant-defense-and-resistance-in-nature
#18
Jack Colicchio
Trichomes, or leaf hairs, are epidermal extensions that take a variety of forms and perform many functions in plants, including herbivore defense. In this study, I document genetically determined variation, within-generation plasticity, and a direct role of trichomes in herbivore defense for Mimulus guttatus. After establishing the relationship between trichomes and herbivory, I test for transgenerational effects of wounding on trichome density and herbivore resistance. Patterns of inter-annual variation in herbivore density and the high cost of plant defense makes plant-herbivore interactions a system in which transgenerational phenotypic plasticity (TPP) is apt to evolve...
January 19, 2017: Journal of Evolutionary Biology
https://www.readbyqxmd.com/read/28101435/microsatellite-markers-for-nuphar-japonica-nymphaeaceae-an-aquatic-plant-in-the-agricultural-ecosystem-of-japan
#19
Toshiaki Kondo, Sonoko Watanabe, Takashi Shiga, Yuji Isagi
PREMISE OF THE STUDY: Nuphar species (Nymphaeaceae) are representative aquatic plants in irrigation ponds in Japanese agricultural ecosystems. We developed 15 polymorphic microsatellite markers for N. japonica and confirmed their utility for its close relatives N. oguraensis var. akiensis and N. ×saijoensis, which originated from natural hybridization between N. japonica and N. oguraensis. METHODS AND RESULTS: Genetic variation was characterized in 15 polymorphic loci in three populations of N...
December 2016: Applications in Plant Sciences
https://www.readbyqxmd.com/read/28100814/predicting-behavioural-responses-to-novel-organisms-state-dependent-detection-theory
#20
Pete C Trimmer, Sean M Ehlman, Andrew Sih
Human activity alters natural habitats for many species. Understanding variation in animals' behavioural responses to these changing environments is critical. We show how signal detection theory can be used within a wider framework of state-dependent modelling to predict behavioural responses to a major environmental change: novel, exotic species. We allow thresholds for action to be a function of reserves, and demonstrate how optimal thresholds can be calculated. We term this framework 'state-dependent detection theory' (SDDT)...
January 25, 2017: Proceedings. Biological Sciences
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