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  1. Article: Experimental transmission of Caligus rogercresseyi between two different fish species.

    González-Gómez, M P / Ovalle, L / Spinetto, C / Oyarzo, C / Oyarzún, R / Menanteau, M / Álvarez, D / Rivas, M / Olmos, P

    Diseases of aquatic organisms

    2020  Volume 141, Page(s) 127–138

    Abstract: Caligus rogercresseyi is the dominant sea louse parasite affecting the salmon and trout industry ... Eleginops maclovinus, which is parasitized mostly by the caligid species Lepeophtheirus spp. and C. rogercresseyi, is ... presumably responsible for the transmission of C. rogercresseyi to salmonids. The aim of this study was ...

    Abstract Caligus rogercresseyi is the dominant sea louse parasite affecting the salmon and trout industry in southern Chile. This parasite has a wide range of native and endemic fish hosts. The Patagonian blenny Eleginops maclovinus, which is parasitized mostly by the caligid species Lepeophtheirus spp. and C. rogercresseyi, is presumably responsible for the transmission of C. rogercresseyi to salmonids. The aim of this study was to characterize the transmission of parasites between different fish species and parasite cohort development under laboratory conditions. Parasite abundances and intensities were quantified. Transmission of parasites from Patagonian blenny to Atlantic salmon Salmo salar was lower (~9%, mainly corresponding to C. rogercresseyi) than from salmon to Patagonian blenny (14.7-26.9%, where only C. rogercresseyi were observed). This suggests that the transmission of C. rogercresseyi from salmon individuals is higher than the transmission from a native fish. Parasite cohorts developed successfully on both fish species, but apparently under different developmental rates. Water temperature, oxygen, and juvenile abundances were the variables that better explained cohort development success and variation in C. rogercresseyi adult abundances over time.
    MeSH term(s) Animals ; Chile/epidemiology ; Copepoda ; Fish Diseases/epidemiology ; Salmo salar ; Salmon ; Salmonidae
    Language English
    Publishing date 2020-09-24
    Publishing country Germany
    Document type Journal Article
    ISSN 0177-5103
    ISSN 0177-5103
    DOI 10.3354/dao03513
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  2. Article ; Online: Epidemiological Factors Associated With Caligus rogercresseyi Infection, Abundance, and Spatial Distribution in Southern Chile

    Manuel Lepe-López / Joaquín Escobar-Dodero / Daniel Rubio / Julio Alvarez / Natalia Zimin-Veselkoff / Fernando O. Mardones

    Frontiers in Veterinary Science, Vol

    2021  Volume 8

    Abstract: Sea lice (Caligus rogercresseyi) are external parasites that affect farmed salmonids in Chile, and ... of the present article. The understanding of the effects and factors entailed by the presence of C. rogercresseyi ... spatial scan statistic was used to identify geographic areas and times of C. rogercresseyi infestation and ...

    Abstract Sea lice (Caligus rogercresseyi) are external parasites that affect farmed salmonids in Chile, and the scale of their sanitary and economic impact cannot be overstated. Even though space–time patterns suppose parasite aggregation, specific locations related to different infestation levels, as well as their associated factors across the geographic range involved, had not been investigated as of the writing of the present article. The understanding of the effects and factors entailed by the presence of C. rogercresseyi may be deemed a key element of Integrated Pest Management (IPM). In the present study, the multivariate spatial scan statistic was used to identify geographic areas and times of C. rogercresseyi infestation and to estimate the factors associated with such patterns. We used official C. rogercresseyi monitoring data at the farm level, with a set of 13 covariates, to provide adjustment within the analyses. The analyses were carried out for a period of 5 years (2012–2016), and they included three fish species (Salmo salar, Oncorhynchus mykiss, and Oncorhynchus kisutch) in order to assess the consistency of the identified clusters. A retrospective multinomial, spatial, and temporal scan test was implemented to identify farm clusters of either of the different categories of C. rogercresseyi infested farms: baseline, medium, and high, based on the control chemical threshold established by the health authority. The baseline represents adequate farm performance against C. rogercresseyi infestation. Then, production and environmental factors of the medium and high infestation farms were compared with the baseline using regression techniques. The results revealed a total of 26 clusters (p < 0.001), of which 12 correspond to baseline, 1 to medium, and the remaining 13 to high infestation clusters. In general, baseline clusters are detected in a latitudinal gradient on estuarine areas, with increasing relative risks to complex island water systems. There is a spatial structure in specific sites, north of Los Lagos Region and central Aysén Region, with high infestation clusters and epidemic peaks during 2013. In addition, average weight, salmon species, chemotherapeutants, latitude, temperature, salinity, and year category are factors associated with these C. rogercresseyi patterns. Recommendations for an IPM plan are provided, along with a discussion that considers the involvement of stock density thresholds by salmon species and the spatial structure of the efficacy of chemical control, both intended to avoid the advance of resistance and to minimize environmental residues.
    Keywords sea lice ; Caligus rogercresseyi ; salmon farming ; host-density ; integrated pest management ; Veterinary medicine ; SF600-1100
    Subject code 333
    Language English
    Publishing date 2021-08-01T00:00:00Z
    Publisher Frontiers Media S.A.
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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  3. Article ; Online: Metabolic costs of walking and arm reaching in persons with mild multiple sclerosis.

    Courter, Robert J / Alvarez, Enrique / Enoka, Roger M / Ahmed, Alaa A

    Journal of neurophysiology

    2023  Volume 129, Issue 4, Page(s) 819–832

    Abstract: Movement slowness is a common and disruptive symptom of multiple sclerosis (MS). A potential cause is that individuals with MS slow down to conserve energy as a behavioral adjustment to heightened metabolic costs of movement. To investigate this prospect, ...

    Abstract Movement slowness is a common and disruptive symptom of multiple sclerosis (MS). A potential cause is that individuals with MS slow down to conserve energy as a behavioral adjustment to heightened metabolic costs of movement. To investigate this prospect, we measured the metabolic costs of both walking and seated arm reaching at five speeds in persons with mild MS (pwMS;
    MeSH term(s) Humans ; Multiple Sclerosis ; Arm ; Walking ; Movement ; Adaptation, Physiological
    Language English
    Publishing date 2023-03-08
    Publishing country United States
    Document type Journal Article ; Research Support, Non-U.S. Gov't ; Research Support, N.I.H., Extramural ; Research Support, U.S. Gov't, Non-P.H.S.
    ZDB-ID 80161-6
    ISSN 1522-1598 ; 0022-3077
    ISSN (online) 1522-1598
    ISSN 0022-3077
    DOI 10.1152/jn.00373.2022
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  4. Article ; Online: Atlantic Oceanic Squids in the "Grey Speciation Zone".

    Fernández-Álvarez, Fernando Á / Sanchez, Gustavo / Deville, Diego / Taite, Morag / Villanueva, Roger / Allcock, A Louise

    Integrative and comparative biology

    2023  Volume 63, Issue 6, Page(s) 1214–1225

    Abstract: Cryptic species complexes represent an important challenge for the adequate characterization of Earth's biodiversity. Oceanic organisms tend to have greater unrecognized cryptic biodiversity since the marine realm was often considered to lack hard ... ...

    Abstract Cryptic species complexes represent an important challenge for the adequate characterization of Earth's biodiversity. Oceanic organisms tend to have greater unrecognized cryptic biodiversity since the marine realm was often considered to lack hard barriers to genetic exchange. Here, we tested the effect of several Atlantic and Mediterranean oceanic barriers on 16 morphospecies of oceanic squids of the orders Oegopsida and Bathyteuthida using three mitochondrial and one nuclear molecular marker and five species delimitation methods. Number of species recognized within each morphospecies differed among different markers and analyses, but we found strong evidence of cryptic biodiversity in at least four of the studied species (Chtenopteryx sicula, Chtenopteryx canariensis, Ancistrocheirus lesueurii, and Galiteuthis armata). There were highly geographically structured units within Helicocranchia navossae that could either represent recently diverged species or population structure. Although the species studied here can be considered relatively passive with respect to oceanic currents, cryptic speciation patterns showed few signs of being related to oceanic currents. We hypothesize that the bathymetry of the egg masses and duration of the paralarval stage might influence the geographic distribution of oceanic squids. Because the results of different markers and different species delimitation methods are inconsistent and because molecular data encompassing broad geographic sampling areas for oceanic squids are scarce and finding morphological diagnostic characters for early life stages is difficult, it is challenging to assess the species boundaries for many of these species. Thus, we consider many to be in the "grey speciation zone." As many oceanic squids have cosmopolitan distributions, new studies combining genomic and morphological information from specimens collected worldwide are needed to correctly assess the actual oceanic squid biodiversity.
    MeSH term(s) Animals ; Phylogeny ; Decapodiformes ; Oceans and Seas ; Biodiversity ; Mitochondria
    Language English
    Publishing date 2023-08-21
    Publishing country England
    Document type Journal Article
    ZDB-ID 2159110-6
    ISSN 1557-7023 ; 1540-7063
    ISSN (online) 1557-7023
    ISSN 1540-7063
    DOI 10.1093/icb/icad116
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  5. Article: In Situ Synthesis of Fe

    Moya, Roger / Gaitán-Álvarez, Johanna / Berrocal, Alexander / Merazzo, Karla J

    Materials (Basel, Switzerland)

    2022  Volume 15, Issue 9

    Abstract: Magnetic wood is a composite material that achieves harmony between both woody and magnetic functions through the active addition of magnetic characteristics to the wood itself. In addition to showing magnetic characteristics, magnetic wood offers low ... ...

    Abstract Magnetic wood is a composite material that achieves harmony between both woody and magnetic functions through the active addition of magnetic characteristics to the wood itself. In addition to showing magnetic characteristics, magnetic wood offers low specific gravity, humidity control and acoustic absorption ability. It has potential for broad applications in the fields of electromagnetic wave absorption, electromagnetic interference shielding, furniture, etc. This work reports on the synthesis of Fe
    Language English
    Publishing date 2022-05-09
    Publishing country Switzerland
    Document type Journal Article
    ZDB-ID 2487261-1
    ISSN 1996-1944
    ISSN 1996-1944
    DOI 10.3390/ma15093394
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  6. Article ; Online: Lymphocytic choriomeningitis arenavirus requires cellular COPI and AP-4 complexes for efficient virion production.

    Byford, Owen / Shaw, Amelia B / Tse, Hiu Nam / Todd, Eleanor J A A / Álvarez-Rodríguez, Beatriz / Hewson, Roger / Fontana, Juan / Barr, John N

    Journal of virology

    2024  Volume 98, Issue 3, Page(s) e0200623

    Abstract: Lymphocytic choriomeningitis virus (LCMV) is a bisegmented negative-sense RNA virus classified within the : Importance: Arenaviruses are rodent-borne, segmented, negative-sense RNA viruses, with several members responsible for fatal human disease, ... ...

    Abstract Lymphocytic choriomeningitis virus (LCMV) is a bisegmented negative-sense RNA virus classified within the
    Importance: Arenaviruses are rodent-borne, segmented, negative-sense RNA viruses, with several members responsible for fatal human disease, with the prototypic member lymphocytic choriomeningitis virus (LCMV) being under-recognised as a pathogen capable of inflicting neurological infections with fatal outcome. A detailed understanding of how arenaviruses subvert host cell processes to complete their multiplication cycle is incomplete. Here, using a combination of gene ablation and pharmacological inhibition techniques, we showed that host cellular COPI and AP-4 complexes, with native roles in cellular vesicular transport, were required for efficient LCMV growth. We further showed these complexes acted on late stages of the multiplication cycle, post-gene expression, with a significant impact on infectious virus egress. Collectively, our findings improve the understanding of arenaviruses host-pathogen interactions and reveal critical cellular trafficking pathways required during infection.
    MeSH term(s) Animals ; Humans ; Chlorocebus aethiops ; Lymphocytic Choriomeningitis ; Lymphocytic choriomeningitis virus/physiology ; Vero Cells ; Virus Replication/genetics ; Adaptor Protein Complex 4/metabolism ; Coat Protein Complex I
    Chemical Substances Adaptor Protein Complex 4 ; Coat Protein Complex I
    Language English
    Publishing date 2024-02-09
    Publishing country United States
    Document type Journal Article
    ZDB-ID 80174-4
    ISSN 1098-5514 ; 0022-538X
    ISSN (online) 1098-5514
    ISSN 0022-538X
    DOI 10.1128/jvi.02006-23
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  7. Article ; Online: Year-Round Monitoring of Contaminants in Neal and Rogers Creeks, Hood River Basin, Oregon, 2011-12, and Assessment of Risks to Salmonids.

    Hapke, Whitney B / Morace, Jennifer L / Nilsen, Elena B / Alvarez, David A / Masterson, Kevin

    PloS one

    2016  Volume 11, Issue 6, Page(s) e0158175

    Abstract: ... to Rogers Creek, but the indices appear to be low overall (<0.1). Endosulfans and pyrethroid insecticides ...

    Abstract Pesticide presence in streams is a potential threat to Endangered Species Act listed salmonids in the Hood River basin, Oregon, a primarily forested and agricultural basin. Two types of passive samplers, polar organic chemical integrative samplers (POCIS) and semipermeable membrane devices (SPMDs), were simultaneously deployed at four sites in the basin during Mar. 2011-Mar. 2012 to measure the presence of pesticides, polybrominated diphenyl ethers (PBDEs), and polychlorinated biphenyls (PCBs). The year-round use of passive samplers is a novel approach and offers several new insights. Currently used pesticides and legacy contaminants, including many chlorinated pesticides and PBDEs, were present throughout the year in the basin's streams. PCBs were not detected. Time-weighted average water concentrations for the 2-month deployment periods were estimated from concentrations of chemicals measured in the passive samplers. Currently used pesticide concentrations peaked during spring and were detected beyond their seasons of expected use. Summed concentrations of legacy contaminants in Neal Creek were highest during July-Sept., the period with the lowest streamflows. Endosulfan was the only pesticide detected in passive samplers at concentrations exceeding Oregon or U.S. Environmental Protection Agency water-quality thresholds. A Sensitive Pesticide Toxicity Index (SPTI) was used to estimate the relative acute potential toxicity among sample mixtures. The acute potential toxicity of the detected mixtures was likely greater for invertebrates than for fish and for all samples in Neal Creek compared to Rogers Creek, but the indices appear to be low overall (<0.1). Endosulfans and pyrethroid insecticides were the largest contributors to the SPTIs for both sites. SPTIs of some discrete (grab) samples from the basin that were used for comparison exceeded 0.1 when some insecticides (azinphos methyl, chlorpyrifos, malathion) were detected at concentrations near or exceeding acute water-quality thresholds. Early life stages and adults of several sensitive fish species, including salmonids, are present in surface waters of the basin throughout the year, including during periods of peak estimated potential toxicity. Based on these data, direct toxicity to salmonids from in-stream pesticide exposure is unlikely, but indirect impacts (reduced fitness due to cumulative exposures or negative impacts to invertebrate prey populations) are unknown.
    MeSH term(s) Animals ; Environmental Monitoring ; Geography ; Oregon ; Pesticides/analysis ; Population Dynamics ; Risk Assessment ; Rivers/chemistry ; Salmonidae ; Spatio-Temporal Analysis ; Water Pollutants, Chemical
    Chemical Substances Pesticides ; Water Pollutants, Chemical
    Language English
    Publishing date 2016-06-27
    Publishing country United States
    Document type Journal Article
    ZDB-ID 2267670-3
    ISSN 1932-6203 ; 1932-6203
    ISSN (online) 1932-6203
    ISSN 1932-6203
    DOI 10.1371/journal.pone.0158175
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  8. Article ; Online: Morphological and Molecular Assessments of Bobtail Squids (Cephalopoda

    Fernando Á. Fernández-Álvarez / Pilar Sánchez / Roger Villanueva

    Frontiers in Marine Science, Vol

    Sepiolidae) Reveal a Hidden History of Biodiversity

    2021  Volume 7

    Abstract: Molecular species delimitation assists taxonomic decisions for challenging species, like cryptic species complexes. Bobtail squids (Family Sepiolidae Leach, 1817) are a very diverse group of benthic and nektonic small to medium size cephalopods with many ...

    Abstract Molecular species delimitation assists taxonomic decisions for challenging species, like cryptic species complexes. Bobtail squids (Family Sepiolidae Leach, 1817) are a very diverse group of benthic and nektonic small to medium size cephalopods with many taxonomic questions to solve. In this study we provided new sequence data for 12 out 17 Mediterranean bobtail squid species including all the genera present i n the area. Other relevant species from other parts of the world were used as comparison. The combined use of several molecular species delimitation methods consistently showed a picture of hidden biodiversity within this family which hinders the use of molecular data isolated from morphological characters. On the one hand, those methods provided contrasting results for the number of recognized species of some morphologically well-defined species. We suggest this can be an effect of recent speciation phenomena followed by an intense morphological drift. On the other hand, cryptic biodiversity was detected among members of several monophyletic clades assigned to the same nominal species, pointing to recent speciation phenomena without a parallel morphological evolution. Although Mediterranean bobtail diversity has been extensively studied for more than a century, a new species of Stoloteuthis Verrill (1881) was discovered and described here, both using molecular and morphological methods. This new research stresses the necessity of combined morphological and molecular studies to correctly assess cephalopod diversity. urn:lsid:zoobank.org:act:57AFBB38-18EA-4F80-B1D4-73519C12694F.
    Keywords Mollusca ; cryptic species ; molecular species delimitation ; systematics ; taxonomy ; new species ; Science ; Q ; General. Including nature conservation ; geographical distribution ; QH1-199.5
    Subject code 590 ; 580
    Language English
    Publishing date 2021-01-01T00:00:00Z
    Publisher Frontiers Media S.A.
    Document type Article ; Online
    Database BASE - Bielefeld Academic Search Engine (life sciences selection)

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  9. Article: Longitudinal study of patients with discrepant results in CLIFT and a solid-phase dsDNA antibody assay: does a gold standard dsDNA assay exist?

    Trujillo Aguilera, Antonio / Bernardo Serrano, Raquel / Navas, Ana / Alcaide Molina, Juan / Alvarez Romero, Paula / Jurado Roger, Aurora

    Lupus science & medicine

    2023  Volume 10, Issue 2

    Abstract: Objective: Antidouble-stranded DNA (dsDNA) antibodies are essential for diagnosis and follow-up of systemic lupus erythematous (SLE). To ensure the best diagnostic approach, most healthcare laboratories opt for a combination of highly sensitive methods, ...

    Abstract Objective: Antidouble-stranded DNA (dsDNA) antibodies are essential for diagnosis and follow-up of systemic lupus erythematous (SLE). To ensure the best diagnostic approach, most healthcare laboratories opt for a combination of highly sensitive methods, such as solid-phase immunoassays, and highly specific methods, such as the
    Methods: We performed an observational, longitudinal and retrospective study on 417 samples from 257 patients who had been referred for suspected connective tissue diseases or followed up after diagnosis. All of them were positive for antinuclear antibodies (ANAs) using an indirect immunofluorescence assay (IFA) on Hep-2 cells, the entry criterion in our laboratory, and positive for FEIA dsDNA. Samples were then tested with CLIFT according to our routine protocol, which includes CLIFT testing after FEIA dsDNA results ≥10 UI/ml. After the assessment of data quality, the final analysis was based on 222 patients.
    Results: Eighty-three patients (37.4%) had positive results in both tests and met the diagnostic criteria for SLE. However, 139 patients (62.6%) had discrepant results (FEIA+, CLIFT-). Of these, 58 patients (41.7%) had a diagnosis of SLE, with 47 (33.8%) having been previously diagnosed and under treatment. The remaining 11 patients (7.9%) had a new diagnosis of SLE, which was made up within 4 years of the initial screening. A total of 81 of the 139 patients (57.5%) with discrepant results did not meet lupus criteria during the follow-up period.
    Conclusions: The study showed that CLIFT could be negative in both treated and newly diagnosed SLE, thus underlining the importance of follow-up of dsDNA-positive results using solid-phase tests. Therefore, quantitative tests such as FEIA could add value to the diagnosis and management of patients with suspected SLE.
    MeSH term(s) Humans ; Antibodies, Antinuclear ; Crithidia ; DNA ; Fluorescent Antibody Technique ; Fluorescent Antibody Technique, Indirect ; Longitudinal Studies ; Lupus Erythematosus, Systemic/diagnosis ; Retrospective Studies
    Chemical Substances Antibodies, Antinuclear ; DNA (9007-49-2)
    Language English
    Publishing date 2023-10-30
    Publishing country England
    Document type Journal Article ; Observational Study
    ZDB-ID 2779620-6
    ISSN 2053-8790
    ISSN 2053-8790
    DOI 10.1136/lupus-2023-000984
    Database MEDical Literature Analysis and Retrieval System OnLINE

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  10. Article ; Online: Hemifield-specific control of spatial attention and working memory: Evidence from hemifield crossover costs.

    Strong, Roger W / Alvarez, George A

    Journal of vision

    2020  Volume 20, Issue 8, Page(s) 24

    Abstract: ... Alvarez & Cavanagh, 2005; Delvenne, 2005). However, this bilateral field advantage does not provide ...

    Abstract Attentional tracking and working memory tasks are often performed better when targets are divided evenly between the left and right visual hemifields, rather than contained within a single hemifield (Alvarez & Cavanagh, 2005; Delvenne, 2005). However, this bilateral field advantage does not provide conclusive evidence of hemifield-specific control of attention and working memory, because it can be explained solely from hemifield-limited spatial interference at early stages of visual processing. If control of attention and working memory is specific to each hemifield, maintaining target information should become more difficult as targets move between the two hemifields. Observers in the present study maintained targets that moved either within or between the left and right hemifields, using either attention (Experiment 1) or working memory (Experiment 2). Maintaining spatial information was more difficult when target items moved between the hemifields compared with when target items moved within their original hemifields, consistent with hemifield-specific control of spatial attention and working memory. However, this pattern was not found for maintaining identity information (e.g., color) in working memory (Experiment 3). Together, these results provide evidence that control of spatial attention and working memory is specific to each hemifield, and that hemifield-specific control is a unique signature of spatial processing.
    MeSH term(s) Attention ; Female ; Humans ; Male ; Memory, Short-Term/physiology ; Spatial Processing/physiology ; Visual Fields/physiology ; Visual Perception ; Young Adult
    Language English
    Publishing date 2020-09-09
    Publishing country United States
    Document type Journal Article ; Research Support, U.S. Gov't, Non-P.H.S.
    ZDB-ID 2106064-2
    ISSN 1534-7362 ; 1534-7362
    ISSN (online) 1534-7362
    ISSN 1534-7362
    DOI 10.1167/jov.20.8.24
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