The Experts below are selected from a list of 138 Experts worldwide ranked by ideXlab platform

William F Gilly - One of the best experts on this subject based on the ideXlab platform.

  • Same-sex sexual behaviour in an oceanic ommastrephid Squid, Dosidicus gigas (Humboldt Squid)
    Marine Biology, 2019
    Co-Authors: Henk Jan T. Hoving, Fernando Á. Fernández-Álvarez, Elan J. Portner, William F Gilly
    Abstract:

    Dosidicus gigas (the Humboldt Squid) is a widely distributed and ecologically important predator in the eastern Pacific Ocean, but its mating behaviour is poorly understood. Individuals of this species have undergone a drastic change in size at maturity in the last years. We investigated mating activity of Humboldt Squid in the Gulf of California in 2013, 2014, and 2015 by quantifying spermatangia deposited in the tissue of the buccal area. In 2015, we encountered the smallest mean mantle length of mature specimens recorded to date in the Gulf of California. In all years, numerous males were encountered that had been mated by other males. Spermatangia in males were deposited on the tissue in similar numbers and in the same location as normally occurs in females (the buccal area), suggesting that male-to-male mating behaviour is similar to male-to-female. This behaviour is referred to as same-sex sexual behaviour and has been described for various taxa, including other cephalopods. Overall similarity in mating frequency between males and females and in body size of mated individuals (in 2015) suggests non-discriminative and brief encounters with body size being a cue for mating. This mating strategy may be beneficial for males, as Humboldt Squid live in groups where competition for mates is likely high. The energetic costs of male-to-male mating events may be counterbalanced by the fitness profits of indiscriminate mating behaviour.

  • prolonged decline of jumbo Squid dosidicus gigas landings in the gulf of california is associated with chronically low wind stress and decreased chlorophyll a after el nino 2009 2010
    Fisheries Research, 2016
    Co-Authors: Carlos J Robinson, Unai Markaida, Jaime Gomez Gutierrez, William F Gilly
    Abstract:

    Abstract Dosidicus gigas (jumbo or Humboldt Squid) is an ecologically relevant predator in the Gulf of California, Mexico, where it supports an economically valuable fishery. The commercial jumbo Squid fishery in the Gulf declined steeply after an El Nino event in 2009–2010, and subsequent landings have remained at historically low levels in the relevant Squid fishing centers (Guaymas, Sonora, and Santa Rosalia, Baja California Sur). In this paper, we examined wind speed and chlorophyll a concentrations on the jumbo Squid fishing grounds as factors that would be expected to be relevant to this prolonged period of low landings. Analysis from local weather stations, remote sensing, and fishery data showed that low jumbo Squid landings from 2010 to 2015 occurred during a period of abnormally weak winter/spring winds and extremely low chlorophyll a concentrations off the East Guaymas Basin. Results indicate that the Squid fishing area in the Guaymas region has been chronically impoverished during this period, and that this area may no longer be a productive habitat for jumbo Squid. In response to this decreased productivity, size-at-maturity of jumbo Squid showed a drastic decrease over the same period. Results are compared with the effect of El Nino 1997–1998 on the jumbo Squid fishery and size-at-maturity of this species in the Gulf of California. The key difference between the recovery phases for El Nino 1997–1998 versus El Nino 2009–2010 was the anomalously low wind intensity as measured in the Guaymas fishing area after 2009.

  • behavioral ecology of jumbo Squid dosidicus gigas in relation to oxygen minimum zones
    Deep-sea Research Part Ii-topical Studies in Oceanography, 2013
    Co-Authors: Julia S Stewart, John C Field, Unai Markaida, William F Gilly
    Abstract:

    Abstract Habitat utilization, behavior and food habits of the jumbo or Humboldt Squid, Dosidicus gigas, were compared between an area recently inhabited in the northern California Current System (CCS) and a historically established area of residence in the Gulf of California (GOC). Low dissolved oxygen concentrations at midwater depths define the oxygen minimum zone (OMZ), an important environmental feature in both areas. We analyzed vertical diving behavior and diet of D. gigas and hydrographic properties of the water column to ascertain the extent to which Squid utilized the OMZ in the two areas. The upper boundary of the OMZ has been shoaling in recent decades in the CCS, and this phenomenon has been proposed to vertically compress the pelagic environment inhabited by aerobic predators. A shoaling OMZ will also bring mesopelagic communities into a depth range with more illumination during daytime, making these organisms more vulnerable to predation by visual predators (i.e. jumbo Squid). Because the OMZ in the GOC is considerably shallower than in the CCS, our study provides insight into the behavioral plasticity of jumbo Squid and how they may respond to a shoaling OMZ in the CCS. We propose that shoaling OMZs are likely to be favorable to jumbo Squid and could be a key indirect factor behind the recent range expansion of this highly migratory predator.

  • Extreme plasticity in life-history strategy allows a migratory predator (jumbo Squid) to cope with a changing climate
    Global Change Biology, 2013
    Co-Authors: Henk Jan T. Hoving, Liz Parassenti, Bilin Liu, Kelly J. Benoit-bird, Patrick Daniel, Zachary W Brown, John C Field, Unai Markaida, William F Gilly, Bernardita Campos
    Abstract:

    Dosidicus gigas (jumbo or Humboldt Squid) is a semelparous, major predator of the eastern Pacific that is ecologically and commercially important. In the Gulf of California, these animals mature at large size (>55 cm mantle length) in 1–1.5 years and have supported a major commercial fishery in the Guaymas Basin during the last 20 years. An El Niño event in 2009–2010, was accompanied by a collapse of this fishery, and Squid in the region showed major changes in the distribution and life-history strategy. Large Squid abandoned seasonal coastal-shelf habitats in 2010 and instead were found in the Salsipuedes Basin to the north, an area buffered from the effects of El Niño by tidal upwelling and a well-mixed water column. The commercial fishery also relocated to this region. Although large Squid were not found in the Guaymas Basin from 2010 to 2012, small Squid were abundant and matured at an unusually small mantle-length (

  • locomotion and behavior of Humboldt Squid dosidicus gigas in relation to natural hypoxia in the gulf of california mexico
    The Journal of Experimental Biology, 2012
    Co-Authors: William F Gilly, Julia S Stewart, Louis D Zeidberg, J A T Booth, Greg Marshall, Kyler Abernathy, Lauren E Bell
    Abstract:

    We studied the locomotion and behavior of Dosidicus gigas using pop-up archival transmitting (PAT) tags to record environmental parameters (depth, temperature and light) and an animal-borne video package (AVP) to log these parameters plus acceleration along three axes and record forward-directed video under natural lighting. A basic cycle of locomotor behavior in D. gigas involves an active climb of a few meters followed by a passive (with respect to jetting) downward glide carried out in a fins-first direction. Temporal summation of such climb-and-glide events underlies a rich assortment of vertical movements that can reach vertical velocities of 3 m s(-1). In contrast to such rapid movements, D. gigas spends more than 80% of total time gliding at a vertical velocity of essentially zero (53% at 0±0.05 m s(-1)) or sinking very slowly (28% at -0.05 to -0.15 m s(-1)). The vertical distribution of Squid was compared with physical features of the local water column (temperature, oxygen and light). Oxygen concentrations of ≤20 μmol kg(-1), characteristic of the midwater oxygen minimum zone (OMZ), can influence the daytime depth of Squid, but this depends on location and season, and Squid can 'decouple' from this environmental feature. Light is also an important factor in determining daytime depth, and temperature can limit nighttime depth. Vertical velocities were compared over specific depth ranges characterized by large differences in dissolved oxygen. Velocities were generally reduced under OMZ conditions, with faster jetting being most strongly affected. These data are discussed in terms of increased efficiency of climb-and-glide swimming and the potential for foraging at hypoxic depths.

Martha Reyesbecerril - One of the best experts on this subject based on the ideXlab platform.

  • effects of marine silages enriched with lactobacillus sakei 5 4 on haemato immunological and growth response in pacific red snapper lutjanus peru exposed to aeromonas veronii
    Fish & Shellfish Immunology, 2012
    Co-Authors: Martha Reyesbecerril, Felipe Ascenciovalle, Maria Esther Macias, Minerva Maldonado, Maurilia Rojas, Maria Angeles Esteban
    Abstract:

    Abstract Combined effects of marine silages enriched with Lactobacillus sakei 5-4 were evaluated on growth performance, immune activity and disease resistance of Pacific red snapper (Lutjanus peru) against Aeromonas veronii infection. The experimental fish were divided into three groups which were fed with each one of the following diets: silage-probiotic-free diet (control, C group), Pacific creole-fish silage diet supplemented with live L. sakei (106 CFU g−1) (FSLact group) and Humboldt Squid silage diet supplemented with live L. sakei (106 CFU g−1) (SSLact group) for 6 weeks. After 6 weeks, fish were immunocompromised with pathogenic A. veronii and spleen and liver samples were processed for histopathological studies. Generally, the results showed enhanced growth performance in fish fed the diet containing SSLact at 6 and 7 weeks compared with fish fed control diet. Addition of SSLact had an increase in plasmatic protein at week 6 and post-challenge. Hemoglobin concentration increased after challenge in fish fed with SSLact compared to control group. At week 6 and post-challenge the results indicated that, the fish groups which received diet supplemented with SSLact revealed significant increase in humoral immune parameters. Histologically, fish fed C diets showed marked fatty degeneration and great activation of melanomacrophage centers compare with SSLact and FSLact groups. These results support the idea that the marine silages with Squid as protein source enriched or combined with L. sakei 5-4 increases the body weight and stimulates the physiological and humoral immune parameters in Pacific red snapper infected with A. veronii.

Maria Angeles Esteban - One of the best experts on this subject based on the ideXlab platform.

  • effects of marine silages enriched with lactobacillus sakei 5 4 on haemato immunological and growth response in pacific red snapper lutjanus peru exposed to aeromonas veronii
    Fish & Shellfish Immunology, 2012
    Co-Authors: Martha Reyesbecerril, Felipe Ascenciovalle, Maria Esther Macias, Minerva Maldonado, Maurilia Rojas, Maria Angeles Esteban
    Abstract:

    Abstract Combined effects of marine silages enriched with Lactobacillus sakei 5-4 were evaluated on growth performance, immune activity and disease resistance of Pacific red snapper (Lutjanus peru) against Aeromonas veronii infection. The experimental fish were divided into three groups which were fed with each one of the following diets: silage-probiotic-free diet (control, C group), Pacific creole-fish silage diet supplemented with live L. sakei (106 CFU g−1) (FSLact group) and Humboldt Squid silage diet supplemented with live L. sakei (106 CFU g−1) (SSLact group) for 6 weeks. After 6 weeks, fish were immunocompromised with pathogenic A. veronii and spleen and liver samples were processed for histopathological studies. Generally, the results showed enhanced growth performance in fish fed the diet containing SSLact at 6 and 7 weeks compared with fish fed control diet. Addition of SSLact had an increase in plasmatic protein at week 6 and post-challenge. Hemoglobin concentration increased after challenge in fish fed with SSLact compared to control group. At week 6 and post-challenge the results indicated that, the fish groups which received diet supplemented with SSLact revealed significant increase in humoral immune parameters. Histologically, fish fed C diets showed marked fatty degeneration and great activation of melanomacrophage centers compare with SSLact and FSLact groups. These results support the idea that the marine silages with Squid as protein source enriched or combined with L. sakei 5-4 increases the body weight and stimulates the physiological and humoral immune parameters in Pacific red snapper infected with A. veronii.

Maria Esther Macias - One of the best experts on this subject based on the ideXlab platform.

  • effects of marine silages enriched with lactobacillus sakei 5 4 on haemato immunological and growth response in pacific red snapper lutjanus peru exposed to aeromonas veronii
    Fish & Shellfish Immunology, 2012
    Co-Authors: Martha Reyesbecerril, Felipe Ascenciovalle, Maria Esther Macias, Minerva Maldonado, Maurilia Rojas, Maria Angeles Esteban
    Abstract:

    Abstract Combined effects of marine silages enriched with Lactobacillus sakei 5-4 were evaluated on growth performance, immune activity and disease resistance of Pacific red snapper (Lutjanus peru) against Aeromonas veronii infection. The experimental fish were divided into three groups which were fed with each one of the following diets: silage-probiotic-free diet (control, C group), Pacific creole-fish silage diet supplemented with live L. sakei (106 CFU g−1) (FSLact group) and Humboldt Squid silage diet supplemented with live L. sakei (106 CFU g−1) (SSLact group) for 6 weeks. After 6 weeks, fish were immunocompromised with pathogenic A. veronii and spleen and liver samples were processed for histopathological studies. Generally, the results showed enhanced growth performance in fish fed the diet containing SSLact at 6 and 7 weeks compared with fish fed control diet. Addition of SSLact had an increase in plasmatic protein at week 6 and post-challenge. Hemoglobin concentration increased after challenge in fish fed with SSLact compared to control group. At week 6 and post-challenge the results indicated that, the fish groups which received diet supplemented with SSLact revealed significant increase in humoral immune parameters. Histologically, fish fed C diets showed marked fatty degeneration and great activation of melanomacrophage centers compare with SSLact and FSLact groups. These results support the idea that the marine silages with Squid as protein source enriched or combined with L. sakei 5-4 increases the body weight and stimulates the physiological and humoral immune parameters in Pacific red snapper infected with A. veronii.

Ali Miserez - One of the best experts on this subject based on the ideXlab platform.

  • Glucose-Responsive Peptide Coacervates with High Encapsulation Efficiency for Controlled Release of Insulin
    2018
    Co-Authors: Zhi Wei Lim, Yuan Ping, Ali Miserez
    Abstract:

    A new glucose-responsive insulin delivery system is fabricated using biomimetic peptide coacervates derived from the Humboldt Squid (Dosidicus Gigas) beak. Both insulin and glucose oxidase are coencapsulated within coacervate microdroplets. The glucose oxidase quickly responds to increasing glucose levels to generate a local acidic environment, thereby rapidly triggering the dissociation of pH-sensitive coacervates to release the insulin cargo. The rate of insulin release is dependent on the glucose level, increases under hyperglycemic conditions, and decreases under normoglycemic conditions. This glucose responsiveness mimics pancreatic β-cell function by releasing insulin according to glucose levels

  • biomimetic production of silk like recombinant Squid sucker ring teeth proteins
    Biomacromolecules, 2014
    Co-Authors: Dawei Ding, Paul A Guerette, Shawn Hoon, Kiat Whye Kong, Tobias Cornvik, Martina Nilsson, Akshita Kumar, Julien Lescar, Ali Miserez
    Abstract:

    The sucker ring teeth (SRT) of Humboldt Squid exhibit mechanical properties that rival those of robust engineered synthetic polymers. Remarkably, these properties are achieved without a mineral phase or covalent cross-links. Instead, SRT are exclusively made of silk-like proteins called “suckerins”, which assemble into nanoconfined β-sheet reinforced supramolecular networks. In this study, three streamlined strategies for full-length recombinant suckerin protein production and purification were developed. Recombinant suckerin exhibited high solubility and colloidal stability in aqueous-based solvents. In addition, the colloidal suspensions exhibited a concentration-dependent conformational switch, from random coil to β-sheet enriched structures. Our results demonstrate that recombinant suckerin can be produced in a facile manner in E. coli and processed from mild aqueous solutions into materials enriched in β-sheets. We suggest that recombinant suckerin-based materials offer potential for a range of biome...

  • Biomimetic Production of Silk-Like Recombinant Squid Sucker Ring Teeth Proteins
    2014
    Co-Authors: Dawei Ding, Paul A Guerette, Shawn Hoon, Kiat Whye Kong, Tobias Cornvik, Martina Nilsson, Akshita Kumar, Julien Lescar, Ali Miserez
    Abstract:

    The sucker ring teeth (SRT) of Humboldt Squid exhibit mechanical properties that rival those of robust engineered synthetic polymers. Remarkably, these properties are achieved without a mineral phase or covalent cross-links. Instead, SRT are exclusively made of silk-like proteins called “suckerins”, which assemble into nanoconfined β-sheet reinforced supramolecular networks. In this study, three streamlined strategies for full-length recombinant suckerin protein production and purification were developed. Recombinant suckerin exhibited high solubility and colloidal stability in aqueous-based solvents. In addition, the colloidal suspensions exhibited a concentration-dependent conformational switch, from random coil to β-sheet enriched structures. Our results demonstrate that recombinant suckerin can be produced in a facile manner in E. coli and processed from mild aqueous solutions into materials enriched in β-sheets. We suggest that recombinant suckerin-based materials offer potential for a range of biomedical and engineering applications

  • the transition from stiff to compliant materials in Squid beaks
    Science, 2008
    Co-Authors: Ali Miserez, Todd Schneberk, Chengjun Sun, Herbert J Waite
    Abstract:

    The beak of the Humboldt Squid Dosidicus gigas represents one of the hardest and stiffest wholly organic materials known. As it is deeply embedded within the soft buccal envelope, the manner in which impact forces are transmitted between beak and envelope is a matter of considerable scientific interest. Here, we show that the hydrated beak exhibits a large stiffness gradient, spanning two orders of magnitude from the tip to the base. This gradient is correlated with a chemical gradient involving mixtures of chitin, water, and His-rich proteins that contain 3,4-dihydroxyphenyl-l-alanine (dopa) and undergo extensive stabilization by histidyl-dopa cross-link formation. These findings may serve as a foundation for identifying design principles for attaching mechanically mismatched materials in engineering and biological applications.