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Wild canids are hosts to a wide range of parasites and can play a role in transmission of zoonoses. As many parasites are transmitted through food webs, and wild canids are at high trophic levels, parasite prevalence and diversity in wild canids can serve as excellent indicators of ecosystem health. Our main objectives were to update knowledge on the composition of gastrointestinal helminths in wild canids from Québec, Canada, and to describe differences in parasite prevalence and diversity among canid species and regions. Hunters and trappers provided whole carcasses of red foxes (Vulpes vulpes) (N = 176), and intestinal tracts of coyotes (Canis latrans) (N = 77) and gray wolves (Canis lupus) (N = 23) harvested for non-research purposes over the winter of 2016–2017. A modified Stoll's centrifugation sucrose flotation on feces of 250 wild canids was used, and eggs of one family and eight genera of parasitic helminths were recovered: diphyllobothriids, Taenia/Echinococcus spp., Capillaria spp., Toxascaris sp., Toxocara sp., Trichuris sp., Uncinaria sp., and Metorchis sp. Adult Taenia spp. cestodes were recovered from 61 of 276 (22%) canids. Six different species (T. hydatigena , T. twitchelli , T. crassiceps , T. polyacantha , T. krabbei, and T. pisiformis -"like") were differentiated based on DNA sequenced from 65 individual adult cestodes using primers for the nicotinamide adenosine dinucleotide dehydrogenase subunit 1 (ND1) and cytochrome c oxidase subunit 1 (CO1) mitochondrial DNA loci. Alaria sp. trematodes infected 89 of 276 canids (32%). A subset were identified as A. americana at the CO1 locus. The marine trematode Cryptocotyle lingua was reported for the first time in foxes in the province of Québec. These results help us understand more fully the predator-prey relationships within this group of canids. This baseline data in regional parasite prevalence and intensity is critical in order to detect future changes following ecological disturbances due to climate and landscape alterations. [Display omitted] • Combining gross examination and fecal flotation improve detection of helminths. • Cestode prevalence is underestimated when diagnosis is based only on eggs in feces. • Foxes had significantly more nematodes and fewer cestodes than wolves and coyotes. • Diets and trophic relationships influence gastrointestinal parasite communities. • Cryptocotyle lingua is reported for the first time in foxes from Québec, Canada. [ABSTRACT FROM AUTHOR]

[Display omitted] • The presence of Apharyngostrigea pipientis in Nearctic, Neotropic and Afrotropic regions shown using CO1. • First known report of A. pipientis in Africa, but no evidence of recent introduction. • First known experimental demonstration of A. pipientis compatibility with a teleost second intermediate host. • Molecular links were found among all life-cycle stages of A. pipientis and Apharyngostrigea simplex. • The whole mitogenome and rDNA operon of A. pipientis show paraphyly in Strigeidae. When subjected to molecular study, species of digeneans believed to be cosmopolitan are usually found to consist of complexes of species with narrower distributions. We present molecular and morphological evidence of transcontinental distributions in two species of Apharyngostrigea Ciurea, 1924, based on samples from Africa and the Americas. Sequences of cytochrome c oxidase I and, in some samples, internal transcribed spacer, revealed Apharyngostrigea pipientis (Faust, 1918) in Tanzania (first known African record), Argentina, Brazil, USA and Canada. Sequences from A. pipientis also match previously published sequences identified as Apharyngostrigea cornu (Zeder, 1800) originating in Mexico. Hosts of A. pipientis surveyed include definitive hosts from the Afrotropic, Neotropic and Nearctic, as well as first and second intermediate hosts from the Americas, including the type host and type region. In addition, metacercariae of A. pipientis were obtained from experimentally infected Poecilia reticulata , the first known record of this parasite in a non-amphibian second intermediate host. Variation in cytochrome c oxidase I haplotypes in A. pipientis is consistent with a long established, wide-ranging species with moderate genetic structure among Nearctic, Neotropic and Afrotropic regions. We attribute this to natural dispersal by birds and find no evidence of anthropogenic introductions of exotic host species. Sequences of CO1 and ITS from adult Apharyngostrigea simplex (Johnston, 1904) from Egretta thula in Argentina matched published data from cercariae from Biomphalaria straminea from Brazil and metacercariae from Cnesterodon decemmaculatus in Argentina, consistent with previous morphological and life-cycle studies reporting this parasite—originally described in Australia—in South America. Analyses of the mitochondrial genome and rDNA operon from A. pipientis support prior phylogenies based on shorter markers showing the Strigeidae Railliet, 1919 to be polyphyletic. [ABSTRACT FROM AUTHOR]

Exercise-related cognitive errors (ECEs) represent a negative lens that distorts individuals' view of exercise. Such thinking can inhibit individuals' behaviour change efforts. Reframing is an evidence-based counselling strategy used to help individuals evaluate the evidence for and against their biased thoughts. Reframing is commonly used within the clinical counselling domain, however, there is no systematic evidence base for its use in an exercise setting for a sample of non-clinical individuals. Two proof-of-concept studies examined whether reframing could attenuate ECEs in the exercise context. Study 1 (N = 22) used a one-group pre-post design to examine cognitive error reframing (REF) in a sample of university staff and students. Study 2 (N = 28) used a randomized design (REF vs. attention control [AC]) to examine ECEs and exercise changes in a sample of individuals with prediabetes. Those receiving REF were prompted to identify, challenge, and reframe their negative exercise thoughts. Both studies demonstrated ECE reductions following reframing. Changes in self-regulatory social cognitions were observed in Study 1. Those receiving REF in Study 2 reported greater increases in their self-reported exercise four weeks following the diabetes program compared to those in AC. REF may help individuals to reduce their biased exercise thoughts when making behaviour change efforts. While findings should be viewed as preliminary given the early research stage and sample sizes, we hope they spark future reframing research within the exercise context. • Reframing was shown to reduce biased thoughts about exercise. • Reframing was shown to reduce decisional struggle and increase exercise intentions. • Those receiving reframing were more active one month later compared to control. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Mitochondrial (mt) genomes and UCEs were obtained from seven species in three families in the Diplostomoidea. • Mt genomes show the order Diplostomida to be paraphyletic, but ultra-conserved genomic elements (UCEs) support it. • Mt genomes and UCEs show monophyly of Diplostomoidea, paraphyly of Diplostomidae. • A new species of Cotylurus and taxonomic changes in Hysteromorpha , Alaria are reported. • Seven complete rDNA operons provided as a resource for future work. Abstract Higher systematics within the Digenea, Carus 1863 have been relatively stable since a phylogenetic analysis of partial nuclear ribosomal markers (rDNA) led to the erection of the Diplostomida Olson, Cribb, Tkach, Bray, and Littlewood, 2003. However, recent mitochondrial (mt) genome phylogenies suggest this order might be paraphyletic. These analyses show members of two diplostomidan superfamilies are more closely related to the Plagiorchiida La Rue, 1957 than to other members of the Diplostomida. A recent phylogeny based on partial cytochrome c oxidase I also indicates one of the groups implicated, the Diplostomoidea Poirier, 1886, is non-monophyletic. To determine if these results were robust to additional taxon sampling, we analyzed mt genomes from seven diplostomoids in three families. To choose between phylogenetic alternatives based on mt genomes and the prior rDNA-based topology, we analyzed hundreds of ultra-conserved genomic elements assembled from shotgun sequencing. The Diplostomida was paraphyletic in the mt genome phylogeny but supported in the ultra-conserved genomic element phylogeny. We speculate this mitonuclear discordance is related to ancient, rapid radiation in the Digenea. Both ultra-conserved genomic elements and mt genomes support the monophyly of the Diplostomoidea and show congruent relationships within it. The Cyathocotylidae Mühling, 1898 are early diverging descendants of a paraphyletic clade of Diplostomidae Poirier, 1886, in which are nested members of the Strigeidae Railliet, 1919; the results support prior suggestions that the Crassiphialinae Sudarikov, 1960 will rise to the family level. Morphological traits of diplostomoid metacercariae appear to be more useful for differentiating clades than those of adults. We describe a new species of Cotylurus Szidat, 1928, resurrect a species of Hysteromorpha Lutz, 1931, and find support for a species of Alaria Schrank, 1788 of contested validity. Complete rDNA operons from seven diplostomoid species are provided as a resource for future studies. [ABSTRACT FROM AUTHOR]

Objective Cognitive errors (CEs) reflect individuals' biased evaluations of context-relevant information. In the exercise domain, a valid form of exercise CE assessment is needed. The Exercise-related Cognitive Errors Questionnaire (E-CEQ) was developed to determine to what extent adults make cognitive errors regarding exercise decisions. The purpose of this study was to develop and provide initial validity evidence for the E-CEQ. Design The current study used an online self-report survey. Method First, 24 initial vignettes representing 6 CEs were created and content validated. Second, data from 364 adults ( M age = 29.1, SD age = 11.6; 81.3% female) was gathered to examine the E-CEQ's factor structure. Finally, data from the 364 participants was used to examine aspects of criterion-related validity. Results A 16-item, three-factor model was retained as the final E-CEQ factor structure and had good psychometric properties (χ 2 = 164.35, df = 75, p < .001; RMSEA = .057; CFI = .947; TLI = .915). Evidence of the questionnaire's predictive utility is provided. For example, exercise CEs were negatively related to exercise and accounted for 4.9% of additional variance beyond the contribution of past exercise in predicting exercise intention. Conclusions The steps taken to examine different forms of validity helped provide a platform from which to continue (a) to study biases linked to cognitive errors and (b) the E-CEQ validation process through ongoing investigation. [ABSTRACT FROM AUTHOR]

Larvae (metacercariae) in some species of Diplostomidae (Platyhelminthes: Digenea) inhabit fish eyes and are difficult to identify to species based on morphology. DNA barcoding has clarified the diversity and life cycles of diplostomids in North America, Europe and Africa, but has seldom been used in parasites sampled in large numbers or at large spatial scales. Here, distance-based analysis of cytochrome c oxidase 1 barcodes and, in some specimens, internal transcribed spacer (ITS-1, 5.8S, ITS-2) sequences was performed for over 2000 diplostomids from Africa, the Middle East, Europe, Asia and the Americas. Fifty-two species of Diplostomum , Tylodelphys and Austrodiplostomum (Digenea: Diplostomidae) were distinguished. The 52 species comprise 12 identified species, six species in two species complexes and 34 putative species, and 33/52 had been delineated in previous studies. Most (23/40) of the unidentified, putative species distinguished by cytochrome c oxidase 1 distances were supported by at least one additional line of evidence. As the intensity of sampling of the 52 species increased, variation in cytochrome c oxidase 1 decreased between and increased within species, while the spatial scale at which species were sampled had no effect. Nonetheless, variation between species always exceeded variation within species. New life-cycle linkages, geographic and host records, and genetic data were recorded in several species, including Tylodelphys jenynsiae , Tylodelphys immer and Diplostomum ardeae . Species of Diplostomum inhabiting the lens are less host-specific and less numerous than those infecting other tissues, suggesting that reduced immune activity in the lens has influenced rates of speciation. [ABSTRACT FROM AUTHOR]

For over 10 years, DNA barcoding has been used to identify specimens and discern species. Its potential benefits in parasitology were recognized early, but its utility and uptake remain unclear. Here we review studies using DNA barcoding in parasites and vectors affecting humans and find that the technique is accurate (accords with author identifications based on morphology or other markers) in 94–95% of cases, although aspects of DNA barcoding (vouchering, marker implicated) have often been misunderstood. In a newly compiled checklist of parasites, vectors, and hazards, barcodes are available for 43% of all 1403 species and for more than half of 429 species of greater medical importance. This is encouraging coverage that would improve with an active campaign targeting parasites and vectors. [ABSTRACT FROM AUTHOR]

Highlights: [•] Negative associations among genetically distinguished Diplostomum species [•] Inter-annual variation in infracommunities surpassed inter-seasonal variation [•] Decline in Diplostomum populations potentially caused by introduced fish species [•] Infracommunity composition, structure not influenced by host ecology or phylogeny. [•] Host length and age had significant effects on infracommunity structure. [ABSTRACT FROM AUTHOR]

Abstract: In this study, sequences from the barcode region of cytochrome c oxidase I (COI) were used to distinguish Diplostomum spp. in a sample of 497 metacercariae collected from diverse fishes of the St. Lawrence River, Canada and findings were corroborated with internal transcribed spacer (ITS) regions of rDNA. Twelve species were detected based on sequences and metacercarial specificity for hosts and tissues. Although this is an unusually high diversity, additional species are likely to exist in the study area. Two species were indistinguishable with ITS data and there is evidence that they may be undergoing hybridization and/or have recently diverged. The ITS sequences of another species are similar to those of Diplostomum pseudospathaceum from Europe, but ITS data are insufficient to show that they are conspecific. Diplostomum spp. that infect tissues other than the lens are more host-specific than species inhabiting the lenses of fishes, which is attributed to the enhanced immunological privilege of the lens site compared with other tissues. Overall, COI sequences were superior to more commonly used ITS markers for delineating species of this important and taxonomically difficult pathogen. [Copyright &y& Elsevier]

The purpose of this study was to examine self-regulatory efficacy (SRE) as an explanatory mediator of high-intensity interval training (HIIT) versus moderate-intensity continuous training (MICT) interventions in relation to physical activity levels over 6- and 12-months after condition assignment. Two mediation models were run. The first model explored initial change in the first 6 months by examining 6-month SRE as a mediator of the relations between the independent variable (condition) and dependent variable (average of 3-month and 6-month physical activity). A second mediation model explored sustained change in the second 6 months by examining 12-month SRE as a mediator of the relations between the independent variable (condition) and dependent variable (average of 9-month and 12-month physical activity). Hayes' PROCESS macro was used to estimate the indirect effect. Adults (n = 99) who were overweight and low-active (mean age = 50.9 years, 69.7% female) were randomized to HIIT or MICT, with participants in both conditions receiving the same brief behavioural counselling. SRE at 12-months post-program was found to mediate the intervention effects (total indirect effect: 8.26 [1.41–17.91]) while SRE at 6-months post program was not found to mediate the intervention effects (total indirect effect: 5.05 [-1.12 – 13.98]). SRE was found to be an explanatory mechanism in predicting greater long-term physical activity engagement for those in MICT compared to HIIT. These findings suggest that participants' perceived capabilities to self-manage their physical activity behaviour accounted for higher levels of maintained physical activity participation among participants in the MICT condition when compared to the HIIT condition one-year following participation in a diabetes prevention program. • Theory-based interventions allow for strong theory testing. • Self-regulatory efficacy mediated sustained physical activity engagement. • Different exercise modalities may require distinct sets of self-regulatory skills. [ABSTRACT FROM AUTHOR]

• Five species of Diplostomoidea are reported in Biomphalaria straminea from Brazil. • Molecular, morphological and experimental studies were conducted on these cercariae. • A distinct species of Hysteromorpha occurs in South America. • A species of Apharyngostrigea was found in Brazil and Argentina. • Probable hosts and life-cycle patterns were inferred for the species found. Trematodes belonging to the superfamily Diplostomoidea have complex life cycles involving birds, mammals and reptiles as definitive hosts, and gastropods and different groups of invertebrates and vertebrates as intermediate hosts. Molecular studies of these parasites are numerous, but data from larval stages in molluscs remain scarce, particularly in South America. The present study focused mainly on five morphotypes of longifurcate cercariae found in Biomphalaria straminea (Dunker, 1848) from Belo Horizonte, Minas Gerais, Brazil, collected between 2009 and 2017. In each morphotype, nuclear internal transcribed spacer (ITS1-5.8S ITS-2) rDNA and mitochondrial cytochrome c oxidase 1 (COI) genes were sequenced. Laboratory-reared fish, Poecilia reticulata Peters, 1859 or snails, Biomphalaria glabrata (Say, 1818) were exposed to cercariae to obtain metacercariae. The morphology of cercariae, experimentally obtained metacercariae, and phylogenetic analyses led to the identification of three species of Diplostomidae [ Austrodiplostomum compactum (Lutz, 1928), Crassiphialinae gen. sp. and Hysteromorpha sp.] and two species of Strigeidae (Cotylurus sp., Apharyngostrigea sp.). Previously published sequences allowed species-level identification for only A. compactum , although provisional identifications were possible in two cases. First, the COI from cercariae of Apharyngostrigea sp. in Brazil matched those of metacercariae from naturally infected Cnesterodon decemmaculatus (Jenyns, 1842) in Argentina; although a positive identification is not possible, the material presents morphological similarities with larval stages previously described for A. simplex. Secondly, Cotylurus sp. resembles C. lutzi. Our analysis of previously published COI sequences suggests that Cotylurus cornutus (Rudolphi, 1808) has a Holarctic distribution. Both the morphology of experimentally obtained metacercariae and COI sequences indicate that Hysteromorpha sp. in Brazil is distinct from congeners in North America [ Hysteromorpha corti (Hughes, 1929)] and Europe [ Hysteromorpha triloba (Rudolphi, 1819)]. [ABSTRACT FROM AUTHOR]

Abstract: Facebook is currently the largest social networking website with an estimated one billion of monthly active users in 2012. While most of the prior research has explored characteristics of Facebook users, less is known about the characteristics of individuals who do not use Facebook. The current study examined personality and social factors that might influence the decision to use Facebook and explored differences between Facebook non-users and frequent users. Online questionnaires examining levels of trust and self-disclosure, number of intimate friendships, peer usage of Facebook and scores on overt and covert narcissism were used for the purpose of the study. The results showed that non-users and frequent users differed on several social and personality characteristics. Facebook non-users had lower tendency to self-disclose, fewer peers participating in the social network and higher covert narcissistic traits. Frequent Facebook users scored higher on overt narcissism and reported more intimate friendships than non-users, indicating that close friendships might actually extend to social networks and contribute to a feeling of closeness and intimacy between friends in both an online and offline context. [Copyright &y& Elsevier]

Species of the genus Posthodiplostomum are intestinal parasites of piscivorous birds with worldwide distribution. Recent molecular surveys have focused on developmental stages from vertebrate hosts, with few sequences from larvae found in molluscs. Moreover, most published molecular data are from collections in North America, Europe and Asia, and there are no data for South American species. In the present study, cercariae found in the freshwater limpet Gundlachia ticaga from Brazil were used for morphological, experimental and molecular studies. The longifurcate cercariae, Neascus -type metacercariae obtained in experimentally infected guppies ( Poecilia reticulata ), and an adult parasite recovered from a mouse were morphologically identified as Posthodiplostomum nanum . Sequences of DNA from internal transcribed spacer (ITS) rDNA and cytochrome c oxidase 1 ( cox1 ) from the cercariae and metacercariae were compared with published data, yielding no matches (ITS divergence ≥ 5.5%, cox1  ≥ 13.9%). Phylogenetic analyses of the ITS sequences suggest paraphyly within the genus Posthodiplostomum , or misidentifications of parasites in molecular studies. For example, ITS sequences of Mesoophorodiplostomum pricei and Posthodiplostomum centrarchi or the unnamed species Posthodiplostomum sp. 8 diverge by only 1.1–1.2% and 0.6%, respectively, and all three species fall within a well-supported clade, suggesting that these isolates are congeneric. The phylogenetic tree obtained for cox1 sequences, although not well resolved, reveals that the type species of the genus, Posthodiplostomum cuticola , does not group with any species previously identified as Posthodiplostomum . Overall, the analyses of molecular data here obtained for P. nanum compared with sequences of related species suggest that a review of this group is necessary. Such studies may result in a split of the genus Posthodiplostomum and the transference of some species currently assigned in this genus to other already described genera. [ABSTRACT FROM AUTHOR]