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81.
Naohisa Kanda Mutsuo Goto Hidehiro Kato Megan V. McPhee Luis A. Pastene 《Conservation Genetics》2007,8(4):853-864
Bryde’s whales (Balaenoptera brydei) differ from other typical baleen whale species because they are restricted to tropical and warm temperate waters in major
oceans, and frequent trans-equatorial movement has been suggested for the species. We tested this hypothesis by analyzing
genetic variation at 17 microsatellite loci (N = 508) and 299 bp of mitochondrial DNA (mtDNA) control region sequences (N = 472) in individuals obtained from the western North Pacific, South Pacific, and eastern Indian Ocean. Combined use of microsatellite
and mtDNA markers allowed us to distinguish between contemporary gene flow and ancestral polymorphism and to describe sex-specific
philopatry. A high level of genetic diversity was found within the samples. Both nuclear and mtDNA markers displayed similar
population structure, indicating a lack of sex-specific philopatry. Spatial structuring was detected using both frequency-based
population parameters and individual-based Bayesian approaches. Whales in the samples from different oceanic regions came
from genetically distinct populations with evidence of limited gene flow. We observed low mtDNA sequence divergence among
populations and a lack of concordance between geographic and phylogenetic position of mtDNA haplotypes, suggesting recent
separation of populations rather than frequent trans-equatorial and inter-oceanic movement. We conclude that current gene
flow between Bryde’s whale populations is low and that effective management actions should treat them as separate entities
to ensure continued existence of the species. 相似文献
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Andrew C. Alba Shawnlei Breeding Annie J. Valuska Christy Sky Megan Dunn Paul J. Schutz Katherine A. Leighty Gina M. Ferrie 《Zoo biology》2019,38(6):498-507
The use of radio frequency identification (RFID) technology is common in animal‐monitoring applications in the wild and in zoological and agricultural settings. RFID is used to track animals and to collect information about movements and other behaviors, as well as to automate or improve husbandry. Disney's Animal Kingdom® uses passive RFID technology to monitor nest usage by a breeding colony of northern carmine bee‐eaters. We implemented RFID technologies in various equipment configurations, initially deploying low‐frequency (LF) 125 kHz RFID and later changing to high‐frequency (HF) 13.56 MHz RFID technology, to monitor breeding behavior in the flock. We installed antennas connected to RFID readers at the entrances of nest tunnels to detect RFID transponders attached to leg bands as birds entered and exited tunnels. Both LF‐RFID and HF‐RFID systems allowed the characterization of nest visitation, including the timing of nest activity, breeding pair formation, identification of egg‐laying females, participation by nonresidents, and detection of nest disruptions. However, we collected a substantially larger volume of data using the increased bandwidth and polling speed inherent with HF‐RFID, which permitted tag capture of multiple birds simultaneously and resulted in fewer missed nest visits in comparison to LF‐RFID. Herein, we describe the evolution of the RFID setups used to monitor nest usage for more than 7 years, the types of data that can be gained using RFID at nests, and how we used these data to gain insights into carmine bee‐eater breeding behavior and improve husbandry. 相似文献
85.
Catherine A. Staton Joo Ricardo Nickenig Vissoci Deena El-Gabri Konyinsope Adewumi Tessa Concepcion Shannon A. Elliott Daniel R. Evans Sophie W. Galson Charles T. Pate Lindy M. Reynolds Nadine A. Sanchez Alexandra E. Sutton Charlotte Yuan Alena Pauley Luciano Andrade Megan Von Isenberg Jinny J. Ye Charles J. Gerardo 《PLoS medicine》2022,19(4)
BackgroundDisease and disability from alcohol use disproportionately impact people in low- and middle-income countries (LMICs). While varied interventions have been shown to reduce alcohol use in high-income countries, their efficacy in LMICs has not been assessed. This systematic review describes current published literature on patient-level alcohol interventions in LMICs and specifically describes clinical trials evaluating interventions to reduce alcohol use in LMICs.Methods and findingsIn accordance with PRISMA, we performed a systematic review using an electronic search strategy from January 1, 1995 to December 1, 2020. Title, abstract, as well as full-text screening and extraction were performed in duplicate. A meta-summary was performed on randomized controlled trials (RCTs) that evaluated alcohol-related outcomes. We searched the following electronic databases: PubMed, EMBASE, Scopus, Web of Science, Cochrane, WHO Global Health Library, and PsycINFO. Articles that evaluated patient-level interventions targeting alcohol use and alcohol-related harm in LMICs were eligible for inclusion. No studies were excluded based on language.After screening 5,036 articles, 117 articles fit our inclusion criteria, 75 of which were RCTs. Of these RCTs, 93% were performed in 13 middle-income countries, while 7% were from 2 low-income countries. These RCTs evaluated brief interventions (24, defined as any intervention ranging from advice to counseling, lasting less than 1 hour per session up to 4 sessions), psychotherapy or counseling (15, defined as an interaction with a counselor longer than a brief intervention or that included a psychotherapeutic component), health promotion and education (20, defined as an intervention encouraged individuals’ agency of taking care of their health), or biologic treatments (19, defined as interventions where the biological function of alcohol use disorder (AUD) as the main nexus of intervention) with 3 mixing categories of intervention types. Due to high heterogeneity of intervention types, outcome measures, and follow-up times, we did not conduct meta-analysis to compare and contrast studies, but created a meta-summary of all 75 RCT studies. The most commonly evaluated intervention with the most consistent positive effect was a brief intervention; similarly, motivational interviewing (MI) techniques were most commonly utilized among the diverse array of interventions evaluated.ConclusionsOur review demonstrated numerous patient-level interventions that have the potential to be effective in LMICs, but further research to standardize interventions, populations, and outcome measures is necessary to accurately assess their effectiveness. Brief interventions and MI techniques were the most commonly evaluated and had the most consistent positive effect on alcohol-related outcomes.Trial registrationProtocol Registry: PROSPERO CRD42017055549Catherine Staton and co-workers report on evidence about interventions against harmful alcohol use in low- and middle-income countries. 相似文献
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Marlene Adlhart Florian Poetsch Mario Hlevnjak Megan Hoogmoed Anton
A Polyansky Bojan Zagrovic 《Nucleic acids research》2022,50(7):4054
During packaging in positive-sense single-stranded RNA (+ssRNA) viruses, coat proteins (CPs) interact directly with multiple regions in genomic RNA (gRNA), but the underlying physicochemical principles remain unclear. Here we analyze the high-resolution cryo-EM structure of bacteriophage MS2 and show that the gRNA/CP binding sites, including the known packaging signal, overlap significantly with regions where gRNA nucleobase-density profiles match the corresponding CP nucleobase-affinity profiles. Moreover, we show that the MS2 packaging signal corresponds to the global minimum in gRNA/CP interaction energy in the unstructured state as derived using a linearly additive model and knowledge-based nucleobase/amino-acid affinities. Motivated by this, we predict gRNA/CP interaction sites for a comprehensive set of 1082 +ssRNA viruses. We validate our predictions by comparing them with site-resolved information on gRNA/CP interactions derived in SELEX and CLIP experiments for 10 different viruses. Finally, we show that in experimentally studied systems CPs frequently interact with autologous coding regions in gRNA, in agreement with both predicted interaction energies and a recent proposal that proteins in general tend to interact with own mRNAs, if unstructured. Our results define a self-consistent framework for understanding packaging in +ssRNA viruses and implicate interactions between unstructured gRNA and CPs in the process. 相似文献
88.
Bernard Y. Amegadzie Charles R. Hanning Megan M. McLaughlin Miriam Burman Lenora B. Cieslinski George P. Livi Theodore J. Torphy 《Cell biology international》1995,19(6):477-484
Recombinant baculoviruses were constructed to express cDNAs encoding two distinct subtypes of human cAMP-specific phosphodiesterase (hPDE4A and hPDE4B). Infection of Spodoptera frugiperda insect cells with the appropriate recombinant baculoviruses resulted in high level production of biologically-active protein as measured by enzymatic activity and immunoblotting using subtype-specific anti-hPDE4 antisera. Both recombinant proteins showed catalytic activity with a low Km (~ 3 μM) for cAMP (with no cGMP hydrolyzing activity) and were inhibited by R-rolipram with apparent Kis of 0.38 and 0.25 μM, respectively. The recombinant enzymes also contained saturable, stereoselective and high-affinity rolipram-binding sites (Kd ~ 2 nM). Thus, insect cell-derived hPDE4s possess kinetic properties analogous to native enzymes as well as to recombinant enzymes produced in yeast. 相似文献
89.
The cellular role of the DNA polymerase encoded by the Saccharomyces cerevisiae POL4 gene is unclear. We have used an epistasis analysis to investigate whether the proteins encoded by the POL4 and RAD27 genes participate in alternative, non-redundant subpathways of DNA base excision repair (BER). We constructed strains in which the genes were deleted singly or in combination and have examined their sensitivity to DNA damaging agents as well as spontaneous mutation frequency. The double deletion strain is no more sensitive to damaging agents and has no higher spontaneous mutation frequency than the most sensitive single mutant. These data indicate that the protein encoded by the POL4 gene does not participate in a non-redundant subpathway of base excision repair under these conditions. We discuss the implications of these results in light of the recent classification of the POL4 gene product as a member of the DNA polymerase lambda family. 相似文献
90.
Mahdi Saatchi Robert D Schnabel Megan M Rolf Jeremy F Taylor Dorian J Garrick 《遗传、选种与进化》2012,44(1):38