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https://www.readbyqxmd.com/read/28823094/impact-of-insecticides-used-in-soybean-crops-to-the-egg-parasitoid-telenomus-podisi-hymenoptera-platygastridae
#1
C S Stecca, A F Bueno, A Pasini, D M Silva, K Andrade, D M Zirondi Filho
The objective of this study was to evaluate possible side effects of insecticides used in soybean crops on pupae and adults of the egg parasitoid Telenomus podisi Ashmead (Hymenoptera: Platygastridae) under laboratory conditions. The protocol was adapted from standard methodology stablished by the Pesticides and Beneficial Organisms Working Group of the International Organization for Biological and integrated Control (IOBC) for Trichogramma cacoeciae (Marchal) (Hymenoptera: Trichogrammatidae). All tested benzoylureas, diacylhydrazines, diamides and spinosins as well as pyrethroid beta-cyfluthrin were harmless to T...
August 19, 2017: Neotropical Entomology
https://www.readbyqxmd.com/read/28823069/current-status-of-cattle-production-system-in-nyagatare-district-rwanda
#2
Eugene Mazimpaka, Francis Mbuza, Tukei Michael, Eugene N Gatari, E M Bukenya, Okwee-Acai James
A study was conducted to characterize the cattle production systems in Nyagatare District, Eastern Province of Rwanda using pre-tested questionnaires, interviews with key informants as well as focus group discussions in a period of 2 months. The respondents were selected by multi-stage sampling at sector and cell levels. Based on the procedure of Krejcie and Morgan (Educational and Psychological Measurement 30:607-610, 1970) to determine the overall sample size, the result indicated that the majority (98.3%) of farms were privately owned by large families of five to seven members, and most farmers (53...
August 19, 2017: Tropical Animal Health and Production
https://www.readbyqxmd.com/read/28823016/de-novo-synthesis-of-linoleic-acid-in-multiple-collembola-species
#3
Miriama Malcicka, Joachim Ruther, Jacintha Ellers
Many ecological interactions in communities take place between consumers and the organisms they feed on. Continuous surplus of specific nutritional compounds in the diet may lead to evolutionary changes in the metabolic capacity of the consumer, leaving the biosynthesis of such compounds prone to genetic decay and render organisms auxotrophic. A nutrient that is essential to many organisms is the unsaturated fatty acid, linoleic acid (LA; 18:2n-6), which is important in the maintenance of cell membrane fluidity and as a precursor for signaling molecules...
August 19, 2017: Journal of Chemical Ecology
https://www.readbyqxmd.com/read/28822812/determinants-of-thermostability-in-the-cytochrome-p450-fold
#4
REVIEW
Kurt L Harris, Raine E S Thomson, Silja J Strohmaier, Yosephine Gumulya, Elizabeth M J Gillam
Cytochromes P450 are found throughout the biosphere in a wide range of environments, serving a multitude of physiological functions. The ubiquity of the P450 fold suggests that it has been co-opted by evolution many times, and likely presents a useful compromise between structural stability and conformational flexibility. The diversity of substrates metabolized and reactions catalyzed by P450s makes them attractive starting materials for use as biocatalysts of commercially useful reactions. However, process conditions impose different requirements on enzymes to those in which they have evolved naturally...
August 16, 2017: Biochimica et Biophysica Acta
https://www.readbyqxmd.com/read/28822625/landscaping-crossover-interference-across-a-genome
#5
REVIEW
Lidan Sun, Jing Wang, Mengmeng Sang, Libo Jiang, Bingyu Zhao, Tangran Cheng, Qixiang Zhang, Rongling Wu
The evolutionary success of eukaryotic organisms crucially depends on the capacity to produce genetic diversity through reciprocal exchanges of each chromosome pair, or crossovers (COs), during meiosis. It has been recognized that COs arise more evenly across a given chromosome than at random. This phenomenon, termed CO interference, occurs pervasively in eukaryotes and may confer a selective advantage. We describe here a multipoint linkage analysis procedure for segregating families to quantify the strength of CO interference over the genome, and extend this procedure to illustrate the landscape of CO interference in natural populations...
August 16, 2017: Trends in Plant Science
https://www.readbyqxmd.com/read/28822572/enantiodifferentiation-of-whisky-and-cognac-lactones-using-gas-chromatography-with-different-cyclodextrin-chiral-stationary-phases
#6
Hans-Georg Schmarr, Maximilian Mathes, Kristina Wall, Frank Metzner, Marius Fraefel
The chiral lactone 5-butyl-4-methyloxolan-2-one or 5-butyl-4-methyldihydro-2(3H)-furanone, often named whisky lactone, is found in oak wood, then contributing to the appreciated flavor of beverages stored in such wooden barrels. Its next higher homologue is named cognac lactone (5-pentyl-4-methyloxolan-2-one or 5-pentyl-4-methyldihydro-2(3H)-furanone), however is much less known, probably due to its minor concentration level. In order to study the direct enantioseparation of both lactones by gas chromatography on chiral stationary phases, individual enantiomers, particularly for cognac lactone were made available...
August 5, 2017: Journal of Chromatography. A
https://www.readbyqxmd.com/read/28822347/screening-and-confirmation-of-steroids-and-nitroimidazoles-in-urine-blood-and-food-matrices-sample-preparation-methods-and-liquid-chromatography-tandem-mass-spectrometric-separations
#7
Ádám Tölgyesi, Enikő Barta, Andrea Simon, Thomas J McDonald, Virender K Sharma
Veterinary drugs containing synthetic anabolic steroid and nitroimidazole active agents are not allowed for their applications in livestock of the European Union (EU). This paper presents analyses of twelve selected steroids and six nitroimidazole antibiotics at low levels (1.56μg/L-4.95μg/L and 0.17μg/kg-2.14μg/kg, respectively) in body fluids and egg incurred samples. Analyses involved clean-up procedures, high performance liquid chromatography (HPLC) separation, and tandem mass spectrometric screening and confirmatory methods...
August 5, 2017: Journal of Pharmaceutical and Biomedical Analysis
https://www.readbyqxmd.com/read/28822013/biomonitoring-of-chemicals-in-biota-of-two-wetland-protected-areas-exposed-to-different-levels-of-environmental-impact-results-of-the-previeni-project
#8
Cristiana Guerranti, Guido Perra, Eva Alessi, Davide Baroni, Dante Caserta, Donatella Caserta, Augusto De Sanctis, Emiliano Leonida Fanello, Cinzia La Rocca, Michela Mariottini, Monia Renzi, Sabrina Tait, Carlo Zaghi, Alberto Mantovani, Silvano Ettore Focardi
The PREVIENI project (funded by the Ministry of Environment) investigated the exposure to endocrine disrupters in samples of human population and environmental biota in Italy. The environmental biomonitoring considered two Italian WWF Oasis, with the aim to compare the presence and effects of endocrine disruptors in organisms from two protected natural areas, respectively, upstream and downstream a chemical emission site. Chemical analysis of pollutants' tissue levels was made on tissues from earthworm, barbell, trout, and coot, selected as bioindicator organisms...
August 18, 2017: Environmental Monitoring and Assessment
https://www.readbyqxmd.com/read/28821969/interleukin-1-receptor-like-1-protein-st2-is-a-potential-biomarker-for-cardiomyopathy-in-duchenne-muscular-dystrophy
#9
Julia Anderson, Haeri Seol, Heather Gordish-Dressman, Yetrib Hathout, Christopher F Spurney
Duchenne muscular dystrophy (DMD) is a rare, fatal X-linked disorder characterized by the lack of dystrophin, a key sarcolemma muscle protein. Cardiac failure is a significant cause of death in DMD subjects. The purpose of our research was to identify potential cardiac serum biomarkers associated with DMD cardiomyopathy. This is an observational, case-controlled study using subjects from the CINRG DMD natural history study with cardiomyopathy (ejection fraction (EF) <55%; shortening fraction (SF) <28%), subjects without cardiomyopathy (EF ≥ 55%; SF ≥ 28%) compared to normal healthy volunteer subjects...
August 18, 2017: Pediatric Cardiology
https://www.readbyqxmd.com/read/28821937/natural-hazard-susceptibility-assessment-for-road-planning-using-spatial-multi-criteria-analysis
#10
Caroline S J Karlsson, Zahra Kalantari, Ulla Mörtberg, Bo Olofsson, Steve W Lyon
Inadequate infrastructural networks can be detrimental to society if transport between locations becomes hindered or delayed, especially due to natural hazards which are difficult to control. Thus determining natural hazard susceptible areas and incorporating them in the initial planning process, may reduce infrastructural damages in the long run. The objective of this study was to evaluate the usefulness of expert judgments for assessing natural hazard susceptibility through a spatial multi-criteria analysis approach using hydrological, geological, and land use factors...
August 18, 2017: Environmental Management
https://www.readbyqxmd.com/read/28821870/enhanced-silicon-availability-leads-to-increased-methane-production-nutrient-and-toxicant-mobility-in-peatlands
#11
Gloria-Maria Susanne Reithmaier, Klaus-Holger Knorr, Sebastian Arnhold, Britta Planer-Friedrich, Jörg Schaller
Peatlands perform important ecosystem functions, such as carbon storage and nutrient retention, which are affected, among other factors, by vegetation and peat decomposition. The availability of silicon (Si) in peatlands differs strongly, ranging from <1 to >25 mg L(-1). Since decomposition of organic material was recently shown to be accelerated by Si, the aim of this study was to examine how Si influences decomposition of carbon and nutrient and toxicant mobilization in peatlands. We selected a fen site in Northern Bavaria with naturally bioavailable Si pore water concentrations of 5 mg/L and conducted a Si addition experiment...
August 18, 2017: Scientific Reports
https://www.readbyqxmd.com/read/28821847/overcoming-the-plasticity-of-plant-specialized-metabolism-for-selective-diterpene-production-in-yeast
#12
Codruta Ignea, Anastasia Athanasakoglou, Aggeliki Andreadelli, Maria Apostolaki, Minas Iakovides, Euripides G Stephanou, Antonios M Makris, Sotirios C Kampranis
Plants synthesize numerous specialized metabolites (also termed natural products) to mediate dynamic interactions with their surroundings. The complexity of plant specialized metabolism is the result of an inherent biosynthetic plasticity rooted in the substrate and product promiscuity of the enzymes involved. The pathway of carnosic acid-related diterpenes in rosemary and sage involves promiscuous cytochrome P450s whose combined activity results in a multitude of structurally related compounds. Some of these minor products, such as pisiferic acid and salviol, have established bioactivity, but their limited availability prevents further evaluation...
August 18, 2017: Scientific Reports
https://www.readbyqxmd.com/read/28821615/distinct-structural-mechanisms-determine-substrate-affinity-and-kinase-activity-of-protein-kinase-c%C3%AE
#13
Sangbae Lee, Titu Devamani, Hyun Deok Song, Manbir Sandhu, Adrien Larsen, Ruth Sommese, Abhinandan Jain, Nagarajan Vaidehi, Sivaraj Sivaramakrishnan
Protein kinase Cα (PKCα) belongs to the family of AGC kinases that phosphorylate multiple peptide substrates. While the consensus sequence motif has been identified and used to explain substrate specificity for PKCα, it does not inform the structural basis of substrate binding and kinase activity for diverse substrates phosphorylated by this kinase. The transient, dynamic, and unstructured nature of this protein-protein interaction has limited structural mapping of kinase-substrate interfaces. Here, using multiscale MD simulation-based predictions and FRET sensor-based experiments, we investigated the conformational dynamics of the kinase-substrate interface...
August 15, 2017: Journal of Biological Chemistry
https://www.readbyqxmd.com/read/28821540/investigating-undergraduate-students-use-of-intuitive-reasoning-and-evolutionary-knowledge-in-explanations-of-antibiotic-resistance
#14
Melissa Richard, John D Coley, Kimberly D Tanner
Natural selection is a central concept throughout biology; however, it is a process frequently misunderstood. Bacterial resistance to antibiotic medications provides a contextual example of the relevance of evolutionary theory and is also commonly misunderstood. While research has shed light on student misconceptions of natural selection, minimal study has focused on misconceptions of antibiotic resistance. Additionally, research has focused on the degree to which misconceptions may be based in the complexity of biological information or in pedagogical choices, rather than in deep-seated cognitive patterns...
2017: CBE Life Sciences Education
https://www.readbyqxmd.com/read/28821139/charge-functionalized-and-mechanically-durable-composite-cryogels-from-q-nfc-and-cs-for-highly-selective-removal-of-anionic-dyes
#15
Yufei Chen, Jing Ru, Biyao Geng, Haiying Wang, Congcong Tong, Chungui Du, Shengchun Wu, Hongzhi Liu
A composite cryogel was prepared from quaternized nanofibrillated cellulose (Q-NFC) and chitosan (CS) through a combination of freeze-drying and cross-linking with epichlorohydrin. The specific surface area of the composite cryogel was approximately two times that of Q-NFC cryogel. And the composite cryogel exhibited superior adsorption properties of anionic dyes than either the Q-NFC or CS cryogel controls. The adsorption isotherm well fitted the Langmuir model with the maximum theoretical adsorption capacity up to 473...
October 15, 2017: Carbohydrate Polymers
https://www.readbyqxmd.com/read/28821071/on-the-use-of-ion-crosslinked-nanocellulose-hydrogels-for-wound-healing-solutions-physicochemical-properties-and-application-oriented-biocompatibility-studies
#16
Alex Basu, Jonas Lindh, Eva Ålander, Maria Strømme, Natalia Ferraz
Calcium ion-crosslinked nanofibrillated cellulose (NFC) hydrogels were investigated as potential materials for wound healing dressings. The physicochemical properties of the hydrogels were examined by rheology and water retention tests. Skin cells and monocytes were selected for application-oriented biocompatibility studies. The NFC hydrogels presented entangled fibrous networks and solid-like behavior. Water retention tests showed the material´s potential to maintain a suitable moist environment for different type of wounds...
October 15, 2017: Carbohydrate Polymers
https://www.readbyqxmd.com/read/28821035/barley-and-yeast-%C3%AE-glucans-as-new-emulsifier-agents-for-the-development-of-aqueous-natural-antifungal-formulations
#17
Marta Salgado, Soraya Rodríguez-Rojo, María José Cocero
Barley and yeast β-glucans were selected, together with lecithin, to encapsulate resveratrol by emulsification-evaporation method to develop new and safer antifungal formulations. Different emulsification techniques were used: high-shear, high pressure and high pressure and temperature emulsification. Morphology, crystallinity, encapsulation efficiency and in vitro antifungal activity against Botrytis cinerea of the different formulations were evaluated. No significant differences between each emulsification procedure in particle size (below 90nm) and in encapsulation efficiency (70-100%) were observed; only barley β-glucan emulsions showed lower efficiency due to the formation of a gel that retained most of the active compound...
October 15, 2017: Carbohydrate Polymers
https://www.readbyqxmd.com/read/28820995/influence-of-monitoring-data-selection-for-optimization-of-a-steady-state-multimedia-model-on-the-magnitude-and-nature-of-the-model-prediction-bias
#18
Hee Seok Kim, Dong Soo Lee
SimpleBox is an important multimedia model used to estimate the predicted environmental concentration for screening-level exposure assessment. The main objectives were (i) to quantitatively assess how the magnitude and nature of prediction bias of SimpleBox vary with the selection of observed concentration data set for optimization and (ii) to present the prediction performance of the optimized SimpleBox. The optimization was conducted using a total of 9604 observed multimedia data for 42 chemicals of four groups (i...
August 12, 2017: Chemosphere
https://www.readbyqxmd.com/read/28820975/features-of-proteolytic-properties-of-tetraphenylporphyrin-complex-with-lanthanide-group-metals
#19
Elena A Tobolkina, Tatiana A Skripnikova, Anna A Starikova, Galina I Shumilova, Andrey A Pendin
Demetallation of metalloporphyrin molecules is one of the essential degradation reactions in photosynthesis. The effect of metalloporphyrin nature on removal of central metals from tetraphenylporphyrin complexes based on lanthanide group metals (Dy, Er, Lu, Ho) has been studied. pH values, at which the metal ions leave the metalloporphyrin complex were established using two-phase spectrophotometric titration with potentiometric pH-control. The pH values decrease with the increase of atomic numbers of lanthanide groups, as well as with increase of 4f-electrons...
August 12, 2017: Spectrochimica Acta. Part A, Molecular and Biomolecular Spectroscopy
https://www.readbyqxmd.com/read/28820588/exploiting-and-understanding-the-selectivity-in-nhc-based-ru-metathesis-catalysts-for-the-ethenolysis-of-cyclic-olefins-to-%C3%AE-%C3%AF-dienes
#20
Pascal S Engl, Celine B Santiago, Christopher P Gordon, Wei-Chih Liao, Alexey Fedorov, Christophe Copéret, Matthew S Sigman, Antonio Togni
A library of 29 homologous Ru-based olefin metathesis catalysts has been tested for ethenolysis of cyclic olefins towards the goal of selectively forming α,ω-diene using cis-cyclooctene as a prototypical substrate. Dissymmetry at the N-heterocyclic carbene (NHC) ligand was identified as a key parameter for controlling the selectivity. The best-performing catalyst bearing an N-CF3 group significantly outperformed the benchmark second-generation Grubbs catalyst in the ethenolysis of cis-cycloctene. Application of this optimal catalyst to the ethenolysis of various norbornenes allows the efficient synthesis of valuable diene intermediates in good yields...
August 18, 2017: Journal of the American Chemical Society
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