Статті в журналах: "Congeneric modelling"

1

Hubbell, Joshua P., Jacob F. Schaefer, Melvin L. Warren, and Kenneth A. Sterling. "Modelling patterns of coexistence of three congeneric headwater fishes." Freshwater Biology 65, no. 6 (March 2020): 1017–27. http://dx.doi.org/10.1111/fwb.13486.

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2

Doucet, J. P., and A. Doucet-Panaye. "Dibenzoylhydrazines as Insect Growth Modulators: Topology-Based QSAR Modelling." Advances in Sciences and Engineering 12, no. 1 (June 25, 2020): 28–40. http://dx.doi.org/10.32732/ase.2020.12.1.28.

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Dibenzoylhydrazines Xa-(C6H5)a-CO-N-(t-Bu)-NH-CO-(C6H5)b-Yb are efficient insect growth regulators with high activity and selectivity toward lepidopteran and coleopteran pests. For 123 congeneric molecules, a quantitative structure activity relationship model was built in the framework of the QSARINS package using 2D, Topology-based, PaDEL descriptors. Variable selection by GA-MLR allows building an efficient multilinear regression linking pEC50 values to nine structural variables. Robustness and quality of the model were carefully examined at various levels: data-fitting (recall), leave-one (or some) - out, internal and external validation (including random splitting), points not in depth investigated in previous works. Various Machine Learning approaches (Partial Least Squares Regression, Projection Pursuit Regression, Linear Support Vector Machine or Three Layer Perceptron Artificial Neural Network) confirm the validity of the analysis, giving highly consistent results of comparable quality, with only a slight advantage for the three-layer perceptron.

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3

De Benedetti, Pier G., Marina Cocchi, M. Cristina Menziani та Francesca Fanelli. "Theoretical quantitative structure-activity analysis and pharmacophore modelling of selective non-congeneric α1a-adrenergic antagonists". Journal of Molecular Structure: THEOCHEM 280, № 2-3 (квітень 1993): 283–90. http://dx.doi.org/10.1016/0166-1280(93)80015-r.

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4

Danuso, Francesco, Giuseppe Zanin, and Ivan Sartorato. "A modelling approach for evaluating phenology and adaptation of two congeneric weeds (Bidens frondosa and Bidens tripartita)." Ecological Modelling 243 (September 2012): 33–41. http://dx.doi.org/10.1016/j.ecolmodel.2012.06.009.

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5

Gonthier, Paolo, Luana Giordano, Elisa Zampieri, Guglielmo Lione, Alfredo Vizzini, Jan V. Colpaert, and Raffaella Balestrini. "An ectomycorrhizal symbiosis differently affects host susceptibility to two congeneric fungal pathogens." Fungal Ecology 39 (June 2019): 250–56. http://dx.doi.org/10.1016/j.funeco.2018.12.008.

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6

Jeon, Donggu, Wonchoel Lee, Ho Young Soh, and Seong-il Eyun. "A New Species of Monstrillopsis Sars, 1921 (Copepoda: Monstrilloida) with an Unusually Reduced Urosome." Diversity 12, no. 1 (December 20, 2019): 9. http://dx.doi.org/10.3390/d12010009.

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Male monstrilloid copepods, described herein as Monstrillopsis paradoxa sp. nov., were collected from the Chuja Islands, Jeju, Korea, using a light trap. They display many of the common features of Monstrillopsis, including large, prominent eyes, an anteriorly positioned oral papilla, and four setae on each caudal ramus. Type-2 modification of the antennules further supports the assignment of the new species to Monstrillopsis. However, the present specimens have an unusually low number of urosomal somites, just three in total, compared to five in males of all congeneric species, and from four (in Cymbasoma) to five in males of all other monstrilloid genera. Up until now, in the Monstrilloida only females of Cymbasoma have been known to have as few as three urosomal somites.

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7

Mammola, Stefano. "Modelling the future spread of native and alien congeneric species in subterranean habitats — the case of Meta cave-dwelling spiders in Great Britain." International Journal of Speleology 46, no. 3 (September 2017): 427–37. http://dx.doi.org/10.5038/1827-806x.46.3.2134.

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8

Verrier, Elise, Emmanuelle Baudry, and Carmen Bessa-Gomes. "Modelling the effects of the repellent scent marks of pollinators on their foraging efficiency and the plant-pollinator community." PLOS ONE 16, no. 9 (September 8, 2021): e0256929. http://dx.doi.org/10.1371/journal.pone.0256929.

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Pollinator insects forage in complex and unpredictable resource landscapes, often using social information from congeneric individuals to acquire knowledge about their environment. It has long been recognized that this process allows them to exploit floral resources more efficiently and thus increase individual fitness. However, by creating correlations between the behaviors of pollinators within a population, this could also indirectly influence the entire plant-pollinator community. One type of social information used by pollinators is the scent mark left on the corolla of flowers by previous visitors, which can be used as a cue to avoid recently depleted resources. We developed a spatially explicit agent-based model to examine the effects, at both individual and community levels, of pollinators using these scent marks. The model simulates a population of pollinators foraging on flowers in a continuous 2D space in which we can vary the density of pollinators. We showed that the use of scent marks as a source of information significantly increased the foraging efficiency of pollinators except when competition between pollinators was very low. At the community level, this also resulted in a marked homogenization between floral resources within the landscape: in the absence of scent marks, the coefficient of variation of the remaining nectar quantity per flower strongly increased with greater pollinator competition, but it remained low at all levels of competition when scent marks were used by the pollinators. Finally, the use of scent marks markedly decreased the number of pollinator flower visits, especially at high levels of pollinator competition, which can potentially reduce the pollination service.

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9

Buban, Ian Cris R., Christian D. Cabiles, Renan U. Bobiles, Alex P. Camaya, and Victor S. Soliman. "Sinusoidal growth, recruitment, mortality, yield-per-recruit analysis of Buried fan scallop Mimachlamys funebris (Reeve, 1853) and their implications for mariculture." Journal of Fisheries 8, no. 2 (July 24, 2020): 828–36. http://dx.doi.org/10.17017/j.fish.217.

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This study described the growth, mortality, recruitment pattern and exploitation rate of the Buried fan scallop (Mimachlamys funebris) in Asid Gulf, Philippines. Monthly length-frequency data (N=3988) from April 2018 to March 2019 were used to examine population parameters using FISAT II. Two estimates of natural mortalities were used to compare variability of limit exploitation rates. Modelling through the oscillating von Bertalanffy growth function revealed that the species is fast growing (K=1.1 year–1) attaining SH∞ of 10.5 cm. Adequacy in the use of the sinusoidal version of the growth formula hinges on the mean annual temperature difference reported in the gulf to be 2°C. Recruitment pattern was continuous and bimodal throughout the year with two high pulses in April–May and September consistent with the reproductive seasonality reported for congeneric species. Fishing mortality coefficients (4.26 and 4.82 year–1) were higher than the natural mortality coefficients (0.543 and 1.1 year–1). Yield and biomass-per-recruit analysis showed that the current exploitation rates are 112% (Ecurr1 = 0.90) and 92% (Ecurr2 = 0.80) higher than the biological reference points adopted for the study particularly E50. These results demonstrate that M. funebris stock is overexploited, which necessitates effective management measures including mariculture.

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10

Fattorini, Simone, Cristina Mantoni, Letizia Di Biase, Giovanni Strona, Loretta Pace, and Maurizio Biondi. "Elevational Patterns of Generic Diversity in the Tenebrionid Beetles (Coleoptera Tenebrionidae) of Latium (Central Italy)." Diversity 12, no. 2 (January 26, 2020): 47. http://dx.doi.org/10.3390/d12020047.

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The concept of generic diversity expresses the ‘diversification’ of species into genera in a community. Since niche overlap is assumed to be higher in congeneric species, competition should increase generic diversity. On the other hand, generic diversity might be lower in highly selective environments, where only species with similar adaptations can survive. We used the distribution of tenebrionid beetles in Central Italy to investigate how generic diversity varies with elevation from sea level to 2400 m altitude. Generic diversity of geophilous tenebrionids decreased sharply with elevation, whereas the generic diversity of xylophilous tenebrionids showed similarly high values across the gradient. These results suggest that geophilous species are more sensitive to variation in environmental factors, and that the advantages of close relationships (similar adaptations to harsh conditions) are greater than the possible drawbacks (competition). This is consistent with the fact that geophilous tenebrionids are mostly generalist detritivores, and hence weakly affected by competition for resources. By contrast, xylophilous species are more protected from harsh/selective conditions, but more limited by competition for microhabitats and food. Our results support the environmental filtering hypothesis for the species composition of tenebrionid beetles along an elevational gradient.

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11

Caruso, Yole. "Thermoregulation comparisons between a threatened native and an invasive lizard species." Herpetological Journal, Volume 31 Number 2 (April 1, 2021): 70–76. http://dx.doi.org/10.33256/hj31.2.7076.

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Lizard thermoregulation is costly and is largely behavioural. Podarcis raffonei, endemic of few islets of the Aeolian archipelago (southern Italy), is one of the most threatened lizards in Europe, its survival being under threat also due to the presence of the congeneric P. siculus, a successful invader characterised by behavioural plasticity and effectiveness and precision at regulating body temperature (Tb). We tested whether thermoregulation behaviour diverges between the two species by analysing (i) the heating rates under a standard thermal condition, and (ii) the temperature at which lizards ended basking (Tfinal) along a thermal gradient. Overall, we found behavioural differences between the two lizards (i.e. P. siculus exhibited lower Tfinal), although both species had comparable heating rates and thermoregulated in the same thermal conditions. The invasive P. siculus had lower Tfinal and, since heating rates were similar between species, it expended less time basking than native P. raffonei. We speculate that the observed thermal ecology differences could provide a selective advantage to P. siculus in the harsh island environment.

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12

Rossetto, Maurizio, Peter D. Wilson, Jason Bragg, Joel Cohen, Monica Fahey, Jia-Yee Samantha Yap, and Marlien van der Merwe. "Perceptions of Similarity Can Mislead Provenancing Strategies—An Example from Five Co-Distributed Acacia Species." Diversity 12, no. 8 (August 6, 2020): 306. http://dx.doi.org/10.3390/d12080306.

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Ecological restoration requires balancing levels of genetic diversity to achieve present-day establishment as well as long-term sustainability. Assumptions based on distributional, taxonomic or functional generalizations are often made when deciding how to source plant material for restoration. We investigate this assumption and ask whether species-specific data is required to optimize provenancing strategies. We use population genetic and environmental data from five congeneric and largely co-distributed species of Acacia to specifically ask how different species-specific genetic provenancing strategies are based on empirical data and how well a simple, standardized collection strategy would work when applied to the same species. We find substantial variability in terms of patterns of genetic diversity and differentiation across the landscape among these five co-distributed Acacia species. This variation translates into substantial differences in genetic provenancing recommendations among species (ranging from 100% to less than 1% of observed genetic variation across species) that could not have been accurately predicted a priori based on simple observation or overall distributional patterns. Furthermore, when a common provenancing strategy was applied to each species, the recommended collection areas and the evolutionary representativeness of such artificially standardized areas were substantially different (smaller) from those identified based on environmental and genetic data. We recommend the implementation of the increasingly accessible array of evolutionary-based methodologies and information to optimize restoration efforts.

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13

Thorson, James T., and Lewis A. K. Barnett. "Comparing estimates of abundance trends and distribution shifts using single- and multispecies models of fishes and biogenic habitat." ICES Journal of Marine Science 74, no. 5 (January 14, 2017): 1311–21. http://dx.doi.org/10.1093/icesjms/fsw193.

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Several approaches have been developed over the last decade to simultaneously estimate distribution or density for multiple species (e.g. “joint species distribution” or “multispecies occupancy” models). However, there has been little research comparing estimates of abundance trends or distribution shifts from these multispecies models with similar single-species estimates. We seek to determine whether a model including correlations among species (and particularly species that may affect habitat quality, termed “biogenic habitat”) improves predictive performance or decreases standard errors for estimates of total biomass and distribution shift relative to similar single-species models. To accomplish this objective, we apply a vector-autoregressive spatio-temporal (VAST) model that simultaneously estimates spatio-temporal variation in density for multiple species, and present an application of this model using data for eight US Pacific Coast rockfishes (Sebastes spp.), thornyheads (Sebastolobus spp.), and structure-forming invertebrates (SFIs). We identified three fish groups having similar spatial distribution (northern Sebastes, coastwide Sebastes, and Sebastolobus species), and estimated differences among groups in their association with SFI. The multispecies model was more parsimonious and had better predictive performance than fitting a single-species model to each taxon individually, and estimated fine-scale variation in density even for species with relatively few encounters (which the single-species model was unable to do). However, the single-species models showed similar abundance trends and distribution shifts to those of the multispecies model, with slightly smaller standard errors. Therefore, we conclude that spatial variation in density (and annual variation in these patterns) is correlated among fishes and SFI, with congeneric fishes more correlated than species from different genera. However, explicitly modelling correlations among fishes and biogenic habitat does not seem to improve precision for estimates of abundance trends or distribution shifts for these fishes.

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14

Petrozzi, Fabio, Stephanie N. Ajong, Nic Pacini, Daniele Dendi, Sery Gonedele Bi, Julia E. Fa, and Luca Luiselli. "Spatial Niche Expansion at Multiple Habitat Scales of a Tropical Freshwater Turtle in the Absence of a Potential Competitor." Diversity 13, no. 2 (February 1, 2021): 55. http://dx.doi.org/10.3390/d13020055.

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Resource partitioning, the division of limited resources by species to help avoid competition, has been observed in freshwater turtle assemblages in several natural systems but has rarely been studied in tropical African ecosystems. Here, we investigate habitat preferences of two congeneric species in the family Pelomedusidae, Pelusios castaneus and P. cupulatta, in riverine/wetland habitats in the southern Ivory Coast (West Africa). Pelusios castaneus is a widespread species across West-central African savannahs and open forests, whereas P. cupulatta is endemic to the Upper Guinean forest region in West Africa. The two species have a similar diet composition (mainly carnivorous) but diverge considerably in body size, P. cupulatta being much larger. We use hand-fishing-nets and fishing funnel traps to record turtles in 18 distinct sites and analyze habitat preferences by species at two spatial scales. At a macro-habitat scale, P. castaneus is captured mainly in marshlands, whereas P. cupulatta is found in both rivers and wetlands. The two species differ significantly in their use of: (i) banks (P. castaneus being found primarily in spots with grassy banks, whereas P. cupulatta is found in spots with forested banks), and (ii) aquatic vegetation (P. cupulatta prefers spots with more abundant aquatic vegetation than P. castaneus), but both species select sites with no or moderate current. Additionally, in sites where P. cupulatta is not found, P. castaneus expands its spatial niche at multiple habitat scales, notably invading waterbodies with forested banks. Our results suggest that these two Pelomedusid turtle species potentially compete in the freshwater habitats in the southern Ivory Coast.

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15

N Liebman, M. "Approach to modelling specificity determinants in receptor-ligand complexes: congeners of serotonin." Journal of Molecular Graphics 4, no. 1 (March 1986): 61–68. http://dx.doi.org/10.1016/0263-7855(86)80096-0.

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16

TAN, MING KAI, SIGFRID INGRISCH, and RODZAY BIN HAJI ABDUL WAHAB. "First Velarifictorus (Orthoptera: Gryllidae, Gryllinae) cricket described from Borneo (Southeast Asia) and notes on a co-occurring congener." Zootaxa 4282, no. 2 (June 26, 2017): 374. http://dx.doi.org/10.11646/zootaxa.4282.2.10.

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Based on newly collected specimens from Brunei, a new species of Velarifictorus Randell, 1964 is described: Velarifictorus temburongensis sp. nov. This represents the first species of the genus Velarifictorus to be described from Borneo. Unexpectedly, the more widespread species Velarifictorus aspersus aspersus (Walker, 1869) was found together with the new species in the same locality, representing a new locality record for V. aspersus in Brunei. We used MaxEnt modelling to test if it was likely that this species occurs in Ulu Temburong and Borneo based on a set of bioclimatic predictors. While MaxEnt modelling showed that V. aspersus can occur in Borneo, it did not convincingly predict its occurrence in Ulu Temburong where it was found. Based on the model, maximum temperature of warmest month, minimum temperature of coldest month and annual precipitation are important bioclimatic variables to predict the distribution.

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17

Magee, Brian, and Douglas Smith. "Risk assessment of dioxin congeners via plant uptake." Human and Ecological Risk Assessment: An International Journal 1, no. 3 (September 1995): 249–82. http://dx.doi.org/10.1080/10807039509380010.

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18

Panda, Roshni, A. Suneetha Susan Cleave, and PK Suresh. "In silico predictive studies of mAHR congener binding using homology modelling and molecular docking." Toxicology and Industrial Health 30, no. 8 (October 18, 2012): 765–76. http://dx.doi.org/10.1177/0748233712463774.

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19

Ghosh, Upal, A. Scott Weber, James N. Jensen, and John R. Smith. "Dissolved PCB congener distribution in generator column solutions." Water Research 32, no. 5 (March 1998): 1373–82. http://dx.doi.org/10.1016/s0043-1354(97)00391-6.

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20

Douben, P. E. T., R. E. Alcock, and K. C. Jones. "Congener specific transfer of PCDD/Fs from air to cows' milk: An evaluation of current modelling approaches." Environmental Pollution 95, no. 3 (1997): 333–44. http://dx.doi.org/10.1016/s0269-7491(96)00136-4.

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21

Kerger, Brent D., Kenneth T. Bogen, Anne E. Loccisano, and James C. Lamb. "Liver tumor potency indicators for technical toxaphene and congeners simulating weathered toxaphene." Human and Ecological Risk Assessment: An International Journal 24, no. 3 (December 22, 2017): 830–46. http://dx.doi.org/10.1080/10807039.2017.1401450.

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22

Kosicki, Jakub Z. "Niche segregation on the landscape scale of two co-existing related congeners in the sympatric zone – modelling approach." Ecological Modelling 468 (June 2022): 109960. http://dx.doi.org/10.1016/j.ecolmodel.2022.109960.

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23

Pires, RFT, M. Pan, AMP Santos, Á. Peliz, D. Boutov, and A. dos Santos. "Modelling the variation in larval dispersal of estuarine and coastal ghost shrimp: Upogebia congeners in the Gulf of Cadiz." Marine Ecology Progress Series 492 (October 31, 2013): 153–68. http://dx.doi.org/10.3354/meps10488.

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24

Namyatova, Anna A. "Climatic niche comparison between closely related trans-Palearctic species of the genus Orthocephalus (Insecta: Heteroptera: Miridae: Orthotylinae)." PeerJ 8 (December 15, 2020): e10517. http://dx.doi.org/10.7717/peerj.10517.

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Previously climatic niche modelling had been studied for only a few trans-Palearctic species. It is unclear whether and to what extent those niches are different, and which climatic variables influence such a wide distribution. Here, environmental niche modelling is performed based on the Worldclim variables using Maxent for eight species of the genus Orthocephalus (Insecta: Heteroptera: Miridae: Orthotylinae). This group belongs to one of the largest insect families and it is distributed across Palearctic. Orthocephalus bivittatus, O. brevis, O. saltator and O. vittipennis are distributed across Europe and Asia; O. coriaceus, O. fulvipes, O. funestus, O. proserpinae have more limited distribution. Niche comparison using ENMTools was also undertaken to compare the niches of these species, and to test whether the niches of closely related species with trans-Palearctic distributions are more similar to each other, than to other congeners. It has been found that climatic niche models of all trans-Palearctic species under study are similar but are not identical to each other. This has been supported by niche geographic projections, climatic variables contributing to the models and variable ranges. Climatic niche models of all the trans-Palearctic Orthocephalus species are also very similar to two species having more restricted distribution (O. coriaceus, O. funestus). Results of this study suggest that trans-Palearctic distributions can have different geographic ranges and be shaped by different climatic factors.

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25

Fonseca, Érica, Camila Both, Sonia Zanini Cechin, and Gisele Winck. "Pet distribution modelling: Untangling the invasive potential of Trachemys dorbigni (Emydidae) in the Americas." PLOS ONE 16, no. 11 (November 11, 2021): e0259626. http://dx.doi.org/10.1371/journal.pone.0259626.

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Human activities have been changing the global biogeographic patterns by the introductions of invasive species. For reptiles, the invasion rate increase of non-native species is remarkably related to the pet trade, especially for freshwater turtles. Here we estimated the invasive potential of the South American turtle Trachemys dorbigni in the Americas using a combination of climatic and human activity variables. We built species distribution models based on data from the native and invasive ranges, using the ensemble model from five different algorithms (GAM, MAXENT, BRT, RF and GBM). We compared the two models’ performance and predictions, one calibrated with only climatic variables (climate-driven), and the second also included a descriptive variable of human activity (climate plus human-driven). Suitable areas for T. dorbigni covered occurrence areas of its congeners and highly diversified ecoregions, such as the eastern USA, the islands of Central America, and the south eastern and eastern Brazilian coast. Our results indicate that human activities allow T. dorbigni to establish populations outside of its original climatic niche. Including human activity variables proved fundamental to refining the results to identify more susceptible areas to invasion and to allow the efficient targeting of prevention measures. Finally, we suggested a set of actions to prevent T. dorbigni becoming a highly impacting species in the areas identified as more prone to its invasion.

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26

Freitas, Matheus P. "MIA-QSAR modelling of anti-HIV-1 activities of some 2-amino-6-arylsulfonylbenzonitriles and their thio and sulfinyl congeners." Organic & Biomolecular Chemistry 4, no. 6 (2006): 1154. http://dx.doi.org/10.1039/b516396j.

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27

Gong, Yuyang, and Joseph V. Depinto. "Desorption rates of two PCB congeners from suspended sediments---II. model simulation." Water Research 32, no. 8 (August 1998): 2518–32. http://dx.doi.org/10.1016/s0043-1354(97)00389-8.

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28

Gong, Yuyang, Joseph V. Depinto, G. Yull Rhee, and Xia Liu. "Desorption rates of two PCB congeners from suspended sediments---I. experimental results." Water Research 32, no. 8 (August 1998): 2507–17. http://dx.doi.org/10.1016/s0043-1354(97)00390-4.

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29

Wood, L. W., G.-Y. Rhee, B. Bush, and E. Barnard. "Sediment desorption of PCB congeners and their bio-uptake by dipteran larvae." Water Research 21, no. 8 (January 1987): 875–84. http://dx.doi.org/10.1016/s0043-1354(87)80002-7.

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30

de M. Oliveira, Ruan C., Myron P. Zalucki, Patrik L. Pastori, and Darren J. Kriticos. "Current and future potential distributions of Helicoverpa punctigera (Lepidoptera: Noctuidae): is this the next FAW?" Bulletin of Entomological Research 112, no. 1 (September 3, 2021): 119–30. http://dx.doi.org/10.1017/s0007485321000638.

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AbstractHelicoverpa punctigera (Wallengren), the native budworm, is an important highly polyphagous pest that has caused serious damage on a wide variety of crops in Australia. In Australia, its range overlaps that of its congener, Helicoverpa armigera (Hübner), a notorious invasive pest globally. We used CLIMEX, a bioclimatic niche modelling software package, to estimate the potential geographical distribution of H. punctigera under current and future climates (A1B scenario). Under both current and future climate conditions, the model indicates that H. punctigera could establish throughout the tropics and subtropics. Comparing the potential distributions under each climate scenario revealed that in the future its potential distribution is likely to shift poleward and into higher altitudes, into areas that are currently too cold as observed in the South of Brazil, Europe, North America, South East Asia, and South Pacific Islands including New Zealand. The projected potential distribution can inform pre- and post-border biosecurity strategies for the management of this pest in each country.

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31

Mauffret, A., A. Temara, and J. Blasco. "Exposure of the marine deposit feeder Hydrobia ulvae to sediment spiked with LAS congeners." Water Research 44, no. 9 (May 2010): 2831–40. http://dx.doi.org/10.1016/j.watres.2010.02.020.

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32

Shapcott, Alison, and Michael Powell. "Demographic structure, genetic diversity and habitat distribution of the endangered, Australian rainforest tree Macadamia jansenii help facilitate an introduction program." Australian Journal of Botany 59, no. 3 (2011): 215. http://dx.doi.org/10.1071/bt10132.

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Macadamia jansenii is endemic to south-east Queensland, Australia, and is currently known from a single population 180 km north of the nearest wild population of its congener, the edible Macadamia integrifolia. A recently developed Macadamia recovery plan identified that this population was under significant threat and recommended a reintroduction program to safeguard against chance extinction of the single wild population. This study undertook demographic population census surveys, genetic analysis, habitat analysis and niche modelling to determine the potential long-term viability for the species, and to guide search and reintroduction programs. We expanded the known population size of the species to ~60 individuals (1 m and taller) spread over a 900-m distance along a single creek clumped into three subpopulations. There was moderate genetic diversity in the species and the subpopulations showed little genetic differentiation. We developed a potential habitat model combining abiotic variables and vegetation associations, and mapped areas of potentially suitable habitat for M. jansenii within its local area. These maps are being used to target searches for other populations and to guide the location of introduction populations.

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33

Nie, X. P., C. Y. Lan, T. C. An, M. H. Wong, and K. B. Li. "Distributions and Congener Patterns of PCBs in Fish from Major Aquaculture Areas in the Pearl River Delta, South China." Human and Ecological Risk Assessment: An International Journal 12, no. 2 (April 2006): 363–73. http://dx.doi.org/10.1080/10807030500537908.

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Jeong, Man-Ki, and Ho Young Soh. "Dasybranchus geojedoensis sp. nov. (Annelida: Capitellidae), a New Capitellid Species from Southern Korea." Diversity 12, no. 8 (July 24, 2020): 290. http://dx.doi.org/10.3390/d12080290.

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Dasybranchusgeojedoensis sp. nov., obtained from the soft sublittoral bottom in southern Korea, is described as a new species. This new species of Dasybranchus is easily distinguishable from its congeners by the protruded parapodial lobes in the final few thoracic chaetigers. Dasybranchus geojedoensis sp. nov. closely resembles D. bipartitus (Schmarda, 1861) in number and position of abdominal branchiae but differs in position of genital pores and lateral organs, range of thoracic tessellated chaetigers, and denticulation of the abdominal hooks. The partial mtCOI gene sequences of the new Korean species were significantly distinct from those of undescribed species of Dasybranchus from Australia. In this study, a key for known species of Dasybranchus is also provided.

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35

M. Hansen, K., J. H. Christensen, C. Geels, J. D. Silver, and J. Brandt. "Modelling impact of climate change on atmospheric transport and fate of persistent organic pollutants in the Arctic." Atmospheric Chemistry and Physics Discussions 15, no. 5 (March 5, 2015): 6509–35. http://dx.doi.org/10.5194/acpd-15-6509-2015.

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Abstract. The Danish Eulerian Hemispheric Model (DEHM) was applied to investigate how projected climate changes will affect the atmospheric transport of 13 persistent organic pollutants (POPs) to the Artic and their environmental fate within the Arctic. Two sets of simulations were performed, one with initial environmental concentrations from a 20 year spin-up simulation and one with initial environmental concentrations set to zero. Each set of simulations consisted of two ten-year time slices representing the present (1990–2000) and future (2090–2100) climate conditions. The same POP emissions were applied in all simulations to ensure that the difference in predicted concentrations for each set of simulations only arises from the difference in climate input. DEHM was driven using meteorological input from the global circulation model, ECHAM/MPI-OM, simulating the SRES A1B climate scenario. Under the applied climate and emission scenarios, the total mass of all compounds was predicted to be up to 20% higher across the Northern Hemisphere. The mass of HCHs within the Arctic was predicted to be up to 39% higher, whereas the change in mass of the PCBs was predicted to range from 14% lower to 17% higher depending on the congener and the applied initial environmental concentrations. The results of this study also indicate that contaminants with no or a short emission history will be more rapidly transported to and build up in the arctic environment in a future warmer climate. The process that dominates the environmental behaviour of POPs in the Arctic under a future warmer climate scenario is the shift in mass of POPs from the surface media to the atmosphere induced by the higher mean temperature. This is to some degree counteracted by higher degradation rates also following the higher mean temperature. The more dominant of these two processes depend on the physical-chemical properties of the compounds. Previous model studies have predicted that the effect of a changed climate on the transport of POPs to the Arctic is moderate relatively to the effect of proposed changes in emissions, which is confirmed in this study. However, the model studies do not agree on whether climate change acts to reduce or increase environmental concentrations of POPs in the Arctic, and further work is needed to resolve this matter.

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Novak, M. A., A. A. Reilly, B. Bush, and L. Shane. "In situ determination of PCB congener-specific first order absorption/desorption rate constants using Chironomus tentans larvae (Insecta: Diptera: Chironomidae)." Water Research 24, no. 3 (March 1990): 321–27. http://dx.doi.org/10.1016/0043-1354(90)90007-s.

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Kayastha, Pushpalata, Milena Roszkowska, Monika Mioduchowska, Magdalena Gawlak, and Łukasz Kaczmarek. "Integrative Descriptions of Two New Tardigrade Species along with the New Record of Mesobiotus skorackii Kaczmarek et al., 2018 from Canada." Diversity 13, no. 8 (August 22, 2021): 394. http://dx.doi.org/10.3390/d13080394.

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Two new tardigrade species from a moss sample collected in Canada, one representing Macrobiotus hufelandi complex and the second one belonging to the genus Bryodelphax, are described. Integrative analysis was undertaken based on morphological and morphometric data (using both light and scanning electron microscopy (SEM)) combined with multilocus molecular analysis (nuclear sequences, i.e., 18S rRNA, 28S rRNA and ITS-2 as well as mitochondrial COI barcode sequences). Based on COI sequences, Macrobiotus birendrai sp. nov. is most similar to Mac. canaricus (p-distance 17%), whereas Bryodelphax mareki sp. nov. is most similar to Bry. parvulus (p-distance 16%). Both species differ also from their congeners in some morphological and morphometric characters of adults and/or details of egg chorion. Additionally, a large population of Mesobiotus skorackii was found in the sample and this is the first report of this species outside its terra typica in Kirghizia. The original description of this species was prepared based solely on the morphology and morphometry, therefore, here we provide updated data for this species enclosing morphometric and molecular data for the Canadian population.

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Witvrouw, M., M. E. Arranz, C. Pannecouque, R. Declercq, H. Jonckheere, J. C. Schmit, A. M. Vandamme, et al. "1,1,3-Trioxo-2H,4H-Thieno[3,4-e][1,2,4]Thiadiazine (TTD) Derivatives: a New Class of Nonnucleoside Human Immunodeficiency Virus Type 1 (HIV-1) Reverse Transcriptase Inhibitors with Anti-HIV-1 Activity." Antimicrobial Agents and Chemotherapy 42, no. 3 (March 1, 1998): 618–23. http://dx.doi.org/10.1128/aac.42.3.618.

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ABSTRACT We report the development of a new group of nonnucleoside reverse transcriptase inhibitors (NNRTIs). One of the most active congeners of this series of 1,1,3-trioxo-2H,4H-thieno[3,4-e][1,2,4]thiadiazine (TTD) derivatives, i.e., 2-(3-fluorobenzyl)-4-cyanomethylen-1,1,3-trioxo-2H,4H-thieno[3,4-e][1,2,4]thiadiazine) (QM96639) was found to inhibit human immunodeficiency virus (HIV) type 1 [HIV-1 (IIIB)] replication in MT-4 cells at a concentration of 0.09 μM. This compound was toxic for the host cells only at a 1,400-fold higher concentration. The TTD derivatives proved effective against a variety of HIV-1 strains, including those that are resistant to 3′-azido-3′-deoxythymidine (AZT), but not against HIV-2 (ROD) or simian immunodeficiency virus (SIV/MAC251). HIV-1 strains containing the L100I, K103N, V106A, E138K, Y181C, or Y188H mutations in their reverse transcriptase (RT) displayed reduced sensitivity to the compounds. Their cross-resistance patterns correlated with that of nevirapine. 2-Benzyl-4-cyanomethylen-1,1,3-trioxo-2H,4H-thieno[3,4-e][1,2,4]thiadiazine (QM96521) enhanced the anti-HIV-1 activity of AZT and didanosine in a subsynergistic manner. HIV-1-resistant virus containing the V179D mutation in the RT was selected after approximately six passages of HIV-1 (IIIB) in CEM cells in the presence of different concentrations of QM96521. From structure-activity relationship analysis of a wide variety of TTD derivatives, a number of restrictions appeared as to the chemical modifications that were compatible with anti-HIV activity. Modelling studies suggest that in contrast to most other NNRTIs, but akin to nevirapine, QM96521 does not act as a hydrogen bond donor in the RT-drug complex.

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Hansen, K. M., J. H. Christensen, C. Geels, J. D. Silver, and J. Brandt. "Modelling the impact of climate change on the atmospheric transport and the fate of persistent organic pollutants in the Arctic." Atmospheric Chemistry and Physics 15, no. 11 (June 15, 2015): 6549–59. http://dx.doi.org/10.5194/acp-15-6549-2015.

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Abstract. The Danish Eulerian Hemispheric Model (DEHM) was applied to investigate how projected climate changes will affect the atmospheric transport of 13 persistent organic pollutants (POPs) to the Arctic and their environmental fate within the Arctic. Three sets of simulations were performed, one with present day emissions and initial environmental concentrations from a 20-year spin-up simulation, one with present day emissions and with initial environmental concentrations set to zero and one without emissions but with initial environmental concentrations from the 20-year spin-up simulation. Each set of simulations consisted of two 10-year time slices representing the present (1990–2000) and future (2090–2100) climate conditions. DEHM was driven using meteorological input from the global circulation model, ECHAM/MPI-OM, simulating the SRES (Special Report on Emissions Scenarios) A1B climate scenario. Under the applied climate and emission scenarios, the total mass of all compounds was predicted to be up to 55 % lower across the Northern Hemisphere at the end of the 2090s than in the 1990s. The mass of HCHs within the Arctic was predicted to be up to 38 % higher, whereas the change in mass of the PCBs was predicted to range from 38 % lower to 17 % higher depending on the congener and the applied initial environmental concentrations. The results of this study also indicate that contaminants with no or a short emission history will be more rapidly transported to and build up in the arctic environment in a future warmer climate. The process that dominates the environmental behaviour of POPs in the Arctic under a future warmer climate scenario is the shift in mass of POPs from the surface media to the atmosphere induced by the higher mean temperature. This is to some degree counteracted by higher degradation rates also following the higher mean temperature. The more dominant of these two processes depends on the physical-chemical properties of the compounds. Previous model studies have predicted that the effect of a changed climate on the transport of POPs to the Arctic is moderate relative to the effect of proposed changes in emissions, which is confirmed in this study. However, the model studies do not agree on whether climate change acts to reduce or increase environmental concentrations of POPs in the Arctic, and further work is needed to resolve this matter.

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Samaai, Toufiek, Thomas L. Turner, Jyothi Kara, Dawit Yemane, Benedicta Biligwe Ngwakum, Robyn P. Payne, and Sven Kerwath. "Confirmation of the southern African distribution of the marine sponge Hymeniacidon perlevis (Montagu, 1814) in the context of its global dispersal." PeerJ 10 (November 25, 2022): e14388. http://dx.doi.org/10.7717/peerj.14388.

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Background Intertidal rocky shore surveys along the South African coastline (∼3,000 km) have demonstrated the presence and abundance of the encrusting orange sponge Hymeniacidon perlevis (Montagu, 1814), a well-known globally distributed species. After analysing the southern African populations, we gained a better understanding of the genetic structure of this now-accepted global species. Apart from confirming the presence of a single population of H. perlevis, we also determined its distribution in the southern African intertidal rocky shore ecosystem, compared its genetic diversity to congeners, predict its global distribution via environmental niche modelling, and discussed possible underlying mechanisms controlling the species’ global distribution. Methods We surveyed the South African coastline and sampled sponges at 53 rocky shore sites spanning over 3,000 km, from Grosse Bucht south of Lüderitz (Namibia) to Kosi Bay on the east coast of South Africa. DNA sequences of the nuclear rDNA internal transcribed spacer (ITS1) and the COI mitochondrial gene were obtained from 61 samples and compared them to a world-wide sample of other H. perlevis sequences. Using environmental predictor variables from the global dataset BIO-ORACLE, we predicted the probability of global occurrence of the species using an ensemble of eight distribution models. Results South African specimens were found to be 99–100% identical to other populations of H. perlevis (=H. sinapium) from other world-wide regions. The presence of a single population of H. perlevis in southern Africa is supported by genetic data, extending its distribution to a relatively wide geographical range spanning more than 4,000 km along the temperate southern African coast. The predicted global occurrence by ensemble model matched well with the observed distribution. Surface temperature mean and range were the most important predictor variables. Conclusion While H. perlevis appears to have been introduced in many parts of the world, its origins in Europe and southern Africa are unclear.

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Jorge, Rafael F., Miquéias Ferrão, and Albertina P. Lima. "Out of Bound: A New Threatened Harlequin Toad (Bufonidae, Atelopus) from the Outer Borders of the Guiana Shield in Central Amazonia Described through Integrative Taxonomy." Diversity 12, no. 8 (August 10, 2020): 310. http://dx.doi.org/10.3390/d12080310.

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We used integrative taxonomy to describe a new species of Atelopus from the lowlands of Central Amazonia in the region of Manaus, Amazonas, Brazil. The new species is geographically isolated from the southernmost species of Atelopus of the Guiana Shield. Atelopus manauensis species nova (sp. nov.) is characterized by the combination of the following characteristics: male snout-vent length range (SVL = 19.1–26.4 mm; n = 11); dorsal and lateral skin smooth; ventral surface entirely white or white with cream-colored gular region; fingers and toes lacking subarticular tubercles and fringes. The advertisement call of the new species has a call duration of 689–840 ms, contains 15–26 pulses, is emitted at an average pulse rate of 25.5 pulses per second, and has a dominant frequency ranging 3088–3610 Hz. The genetic divergence between the new species and its morphologically most similar congeners (A. spumarius and A. pulcher) is greater than 4%. Atelopus manauensis sp. nov. is closely related to species of the A. hoogmoedi complex inhabiting the Guiana Shield. The new species has a small geographic distribution (approximately 4500 km2) in a landscape that is strongly threatened by the growth of Manaus, the largest city in Brazilian Amazonia. The new species is considered critically endangered and in need of urgent conservation measures.

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Smith, Chase H., and Nathan A. Johnson. "A Comparative Phylogeographic Approach to Facilitate Recovery of an Imperiled Freshwater Mussel (Bivalvia: Unionida: Potamilus inflatus)." Diversity 12, no. 7 (July 17, 2020): 281. http://dx.doi.org/10.3390/d12070281.

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North American freshwaters are among the world’s most threatened ecosystems, and freshwater mussels are among the most imperiled inhabiting these systems. A critical aspect of conservation biology is delineating patterns of genetic diversity, which can be difficult when a taxon has been extirpated from a significant portion of its historical range. In such cases, evaluating conservation and recovery options may benefit by using surrogate species as proxies when assessing overall patterns of genetic diversity. Here, we integrate the premise of surrogate species into a comparative phylogeographic framework to hypothesize genetic relationships between extant and extirpated populations of Potamilus inflatus by characterizing genetic structure in co-distributed congeners with similar life histories and dispersal capabilities. Our mitochondrial and nuclear sequence data exhibited variable patterns of genetic divergence between Potamilus spp. native to the Mobile and Pascagoula + Pearl + Pontchartrain (PPP) provinces. However, hierarchical Approximate Bayesian Computation indicated that the diversification between Mobile and PPP clades was synchronous and represents a genetic signature of a common history of vicariance. Recent fluctuations in sea-level appear to have caused Potamilus spp. in the PPP to form a single genetic cluster, providing justification for using individuals from the Amite River as a source of brood stock to re-establish extirpated populations of P. inflatus. Future studies utilizing eDNA and genome-wide molecular data are essential to better understand the distribution of P. inflatus and establish robust recovery plans. Given the imperilment status of freshwater mussels globally, our study represents a useful methodology for predicting relationships among extant and extirpated populations of imperiled species.

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Bessudova, Anna, Yurij Bukin, and Yelena Likhoshway. "Dispersal of Silica-Scaled Chrysophytes in Northern Water Bodies." Diversity 13, no. 7 (June 23, 2021): 284. http://dx.doi.org/10.3390/d13070284.

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Silica-scaled chrysophytes have an ancient origin; nowadays they inhabit many northern water bodies. As the territories above the 60th parallel north were under the influence of glaciers during the Late Pleistocene, the local water bodies and their microalgal populations formed mainly during the Early Holocene. Now, the arctic, sub-arctic and temperate zones are located here and the water bodies in these regions have varying environmental characteristics. We analyzed the dispersal of silica-scaled chrysophytes in 193 water bodies in 21 northern regions, and for 135 of them determined the role of diverse environmental factors in their species composition and richness using statistical methods. Although the species composition and richness certainly depend on water body location, water temperature and conductivity, regions and individual water bodies with similar species composition can be significantly distant in latitudinal direction. Eighteen species and one variety from 165 taxa occurring here have clear affinities to fossil congeners; they have been encountered in all regions studied and amount to 6–54% of the total number of silica-scaled chrysophytes. We also compared the distribution of the species with a reconstruction of glacier-dammed lakes in the Northern Hemisphere in the Late Pleistocene–Early Holocene. The dispersal of silica-scaled chrysophytes in the northern water bodies could take place in the Late Pleistocene–Early Holocene over the circumpolar freshwater network of glacier-dammed lakes, the final Protista composition being subject to the environmental parameters of each individual water body and the region where the water body is located. This species dispersal scenario can also be valid for other microscopic aquatic organisms as well as for southerly water bodies of the Northern Hemisphere.

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Grimm, Jaime, Jaimie T. A. Dick, Hugo Verreycken, Jonathan M. Jeschke, Stefan Linzmaier, and Anthony Ricciardi. "Context-dependent differences in the functional responses of conspecific native and non-native crayfishes." NeoBiota 54 (February 12, 2020): 71–88. http://dx.doi.org/10.3897/neobiota.54.38668.

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Invasive species are proliferating globally and cause a range of impacts, necessitating risk assessment and prioritization prior to management action. Experimentally derived estimates of per capita effects (e.g. functional responses) have been advocated as predictors of field impacts of potential invaders. However, risk assessments based on estimates from single populations can be misleading if per capita effects vary greatly across space and time. Here, we present a large-scale, multi-population comparison of per capita effects of the American spinycheek crayfish, Faxonius (formerly Orconectes) limosus—a species with an extensive invasion history in eastern North America and Europe. Functional responses were measured on individuals from six geographically disparate populations of F. limosus in its native and invaded ranges on two continents. These revealed inter-population differences in both the maximum feeding rate and functional response type that could not be explained by the biogeographic origin of the population nor by time since the invasion. We propose that other differences in source communities (including the presence of competitors) impose selective pressures for phenotypic traits that result in dissimilar per capita effects. We also compared functional responses of the congeners F. limosus and F. virilis in the presence and absence of potential competitors to examine indirect competitive effects on feeding behaviour. The maximum feeding rate of F. limosus, but not F. virilis, was suppressed in the presence of heterospecific and conspecific competitors, demonstrating how the per capita effects of these species can differ across biotic contexts. In the competitor-presence experiments, individuals from the invasive population of F. limosus consistently had a higher maximum feeding rate than those of the native F. virilis, regardless of treatment. Our results caution against invasion risk assessments that use information from only one (or a few) populations or that do not consider the biotic context of target habitats. We conclude that comparative functional responses offer a rapid assessment tool for invader ecological impacts under context dependencies when multiple populations are analyzed.

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Pinho, F. F., L. P. Lemos, A. Montanarin, H. R. El Bizri, J. Santos, R. M. Rabelo, J. Valsecchi, E. E. Ramalho, and A. P. Paglia. "Modelling the impact of hunting on the coexistence of congeneric deer species in Central Amazonia." Journal of Zoology, April 4, 2022. http://dx.doi.org/10.1111/jzo.12970.

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Licona, Jessica S. F., Adriana C. de Faria, Ingrid V. Pereira, Joyce K. Daré, and Matheus P. Freitas. "MIA-QSAR analysis of an increased data set of 1,3,4-oxa/thiadiazole nematicides to enhance the molecular diversity and agrochemical candidacy." Nematology, July 12, 2022, 1–9. http://dx.doi.org/10.1163/15685411-bja10174.

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Summary Tylenchulus semipenetrans nematodes affect citrus crops and may develop resistance to commercially available nematicides. In this sense, two series of 1,3,4-oxa- and thiadiazole compounds have been recently synthesised and tested as nematicides against T. semipenetrans, demonstrating promising results. We report herein a molecular modelling study that combines these two series of congeneric compounds to form a single and enhanced data set. The chemical structures of these compounds were correlated with the respective nematicidal activities (pLC50) using multivariate image analysis (MIA) descriptors in quantitative structure-activity relationship (QSAR) analysis. The partial least squares (PLS) regression yielded reliable and predictive models (, , and ). Therefore, novel 1,3,4-oxa- and thiadiazole derivatives were proposed and a few of them exhibited predicted nematicidal performance better than those of the parent compounds.

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AlShammari, Talal, Paul Jennings, and Brett Williams. "National study of emergency medical services core competencies: a confirmatory factor analysis." Australasian Journal of Paramedicine 16 (July 29, 2019). http://dx.doi.org/10.33151/ajp.16.706.

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IntroductionInternationally, the development of emergency medical services (EMS) educational standards from a post-employment to pre-employment model has gained considerable momentum. In Saudi Arabia specifically, the evolution to university-based EMS degrees has proceeded swiftly. However, the fast pace of development has contributed to considerable disparities in educational approaches between university programs. Therefore, the development of an empirically-based core competency framework is of considerable importance. The aim of this paper is to utilise confirmatory factor analysis (CFA) through structural equation modelling to confirm the theoretically developed Saudi ParamEdic Competency Scale (SPECS) model.MethodsA national cross-sectional study design with purposive sampling technique was utilised with Saudi Red Crescent Authority healthcare providers. The SPECS instrument included 41 core competency items measured on a self-reported Likert scale. The maximum likelihood method was used with all the one factor congeneric and complete CFA models.ResultsIn total, 477 EMS healthcare professionals contributed to the study: 444 (93.1%) men and 33 (6.9%) women. Of the participants, 282 (59.1%) were 29–39 years of age and 264 (55.3%) had 5 to 9 years’ experience. A CFA of the SPECS model confirmed five congeneric factors within the adequate fit measurement indices: professionalism, preparedness, communication, clinical, and personal. There was one higher order factor titled ‘paramedic competency’.ConclusionThe CFA results support the SPECS as a reliable, valid, unidimensional and psychometrically sound model for operationalisation into Saudi university curricula. The confirmed model is made up of 27 items with five factors and an overarching latent higher order construct. The SPECS model represents an empirically developed blueprint for adoption into Saudi Arabian university programs.

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Hsiao, Yu-Yu, Oi-Man Kwok, and Mark H. C. Lai. "Modeling Measurement Errors of the Exogenous Composites From Congeneric Measures in Interaction Models." Structural Equation Modeling: A Multidisciplinary Journal, July 30, 2020, 1–11. http://dx.doi.org/10.1080/10705511.2020.1782206.

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Notenboom, Sylvia, Ans Punt, Rudolf Hoogenveen, Marco J. Zeilmaker, Ron L. A. P. Hoogenboom, and Bas G. H. Bokkers. "A congener-specific modelling approach for the transfer of polychlorinated dibenzo-p-dioxins and dibenzofurans and dioxin-like polychlorinated biphenyls from feed to eggs of laying hens." Food Additives & Contaminants: Part A, November 17, 2022, 1–14. http://dx.doi.org/10.1080/19440049.2022.2137301.

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Jiang, Lin, Qi Wang, Hui Liu, and Juejun Yao. "Influence of Degradation Behavior of Coexisting Chlorobenzene Congeners Pentachlorobenzene, 1,2,4,5-Tetrachlorobenzene, and 1,2,4-Trichlorobenzene on the Anaerobic Reductive Dechlorination of Hexachlorobenzene in Dye Plant Contaminated Soil." Water, Air, & Soil Pollution 226, no. 9 (August 14, 2015). http://dx.doi.org/10.1007/s11270-015-2559-3.

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