Evaluación de Diferentes Concentraciones de Tricaína (MS-222) en el Transporte de Chitas (Anisotremus scapularis) Juveniles

The use of tricaine (MS-222) as sedative agent for transporting of Anisotremus scapularis juveniles was evaluated. A simulated transport of 24 hours was performed at two temperatures (15 and 19 °C) using the anaesthetic concentrations of 0, 15, 20 and 25 mg.L-1 in polyethylene bags (50% seawater - 50% pure oxygen). At the beginning and the end of the simulation temperature, dissolved oxygen saturation, pH and ammonia excretion rate were monitored. On fishes, the loss of balance (%) and survival (%) were monitored at the end of the simulation and after an additional recovery time of 24 hours. The results showed that use of tricaine favours the reduction of ammonia excretion, however, tricaine doses over 20 mg.L-1 significantly increase the loss of balance in fish. Furthermore, the sedating effect is magnified at lower temperature (15 °C). On the other hand, the water pH is affected showing an average decrease of 1.44 during the transport simulation in all treatments. Based on the results, transport of Peruvian grunt juveniles using tricaine in a dose of at 15 mg.L-1 at 19 °C is recommended.Se evaluó el uso de la tricaína (MS-222) como agente sedante para su uso en el transporte de juveniles Anisotremus scapularis. Para ello, se realizó un transporte simulado de 24 horas a dos temperaturas (15 y 19 °C) usando concentraciones del anestésico de 0, 15, 20 y 25 mg.L-1 en bolsas de polietileno (50% agua de mar - 50% oxígeno puro). Se monitoreó, tanto al inicio como al final de la simulación, la temperatura, saturación de oxígeno disuelto, pH y tasa de excreción individual de amonio. En los peces se evaluó la pérdida de equilibrio (%) y sobrevivencia (%) al término de la simulación y luego de un tiempo de recuperación de 24 horas adicionales. Los resultados muestran que el uso de tricaína favorece la disminución de la excreción de amonio; sin embargo, dosis superiores a 20 mg.L-1 de tricaína incrementan considerablemente la perdida de equilibrio. Además, el efecto de sedación es más intenso a temperaturas más bajas (15 °C). Por otro lado, el pH del agua se ve afectado mostrando una disminución promedio de 1.44 durante la simulación del transporte en todos los tratamientos. En base a los resultados se recomienda el transporte de juveniles de chita a 19 °C con uso de tricaína a 15 mg.L-1

Aprovechamiento de los residuos blandos de concha de abanico, Argopecten purpuratus (Lamarck, 1819), para producir harina de alto contenido proteico

The scallop soft waste obtained during processing is discarded, generating environmental liabilities to the mariculture industry in Peru. However, these residues constitute a potential raw material to produce meal for balanced feeds. In this sense, a methodology was developed for the elaboration of meal from the soft residues of the Peruvian scallop. The product obtained had a composition of 61% protein, 7.5% fat and 11.7% moisture. The development of technologies that allow the processing of large volumes of waste could contribute to the more efficient and profitable use of this raw material.Los residuos blandos de concha de abanico obtenidos durante su procesamiento son descartados, generando pasivos ambientales a la industria de la maricultura en el Perú. Sin embargo, estos residuos constituyen una potencial materia prima para la elaboración de harina con fines de formulación de alimento balanceado. En este sentido, se desarrolló una metodología para la elaboración de harina a partir de los residuos blandos de la concha de abanico. El producto final obtenido tuvo una composición de 61% de proteínas, 7.5% de grasas y 11.7% de humedad. El desarrollo de tecnologías que permitan el procesamiento de grandes volúmenes de residuos de concha de abanico podría contribuir al uso más eficiente y rentable de esta materia prima

Optimización del tratamiento térmico para la inducción al desove de Argopecten purpuratus (Mollusca: Bivalvia)

Based on methodologies currently used in commercial hatcheries, four thermic treatments were compared to induce the gametes expulsion of Argopecten purpuratus. The treatments evaluated included: 1) gradual increase in temperature, 2) gradual decrease, 3) 5 °C thermal-shock, 4) 10 °C thermal-shock and 5) control at constant temperature 16 °C. After induction, the number of fertilized oocytes in each treatment was estimated. The results show that a gradual increase in temperature between 16 and 26 °C causes a significantly higher proportion of fertilized oocytes compared to other treatments

Perfil de ácidos grasos y contenido energético en músculo de juveniles de cabrilla (Paralabrax humeralis) acondicionados al cautiverio

The fatty acids profile and energy content in muscle of juveniles of Paralabrax humeralis conditioned at three temperatures (12, 17 and 22 °C) for a period of 90 days was evaluated. For this purpose, 2 m3 fiberglass tanks connected to water recirculation systems with temperature control were used. The fishes were fed with commercial balanced feed (pellets) of 4 mm diameter, 42% protein and 12% fat twice a day. Every 30 days the weight and length of all fishes was recorded. In addition, six fish per acclimation temperature were sacrificed to measure fatty acids concentrations and energy content of muscle tissue. The observations showed that P. humeralis quickly accepts the artificial feed reaching a 95% survival during the evaluation period. The muscle concentration of linoleic and linolenic acids increased more than 100% in the three temperature groups. Contrarily, the concentration of docosahexaenoic acid (DHA), arachidonic acid (ARA), docosapentaenoic acid (DPA) and eicosapentaenoic acid (EPA) decreased by 48, 45, 26 and 20% respectively. The energy content in muscle increased 13% during the conditioning period. It is concluded that P. humeralis adapts quickly to the conditions of captivity; however, the feed provided must contain higher amounts of ARA, EPA, DPA and DHA.Se evaluó el perfil de ácidos grasos y contenido energético en músculo de juveniles de Paralabrax humeralis acondicionados a tres temperaturas (12, 17 y 22 °C) por un periodo de 90 días. Se utilizaron tanques de fibra de vidrio de 2 m3 conectados a sistemas de recirculación de agua con control de temperatura. Los peces recibieron dos veces al día alimento balanceado comercial (pellets) de 4 mm de diámetro, 42% de proteína y 12% de grasa. Cada 30 días se registró el peso y longitud de todos los peces. Además, seis peces por temperatura de aclimatación fueron sacrificados para medir las concentraciones de ácidos grasos y el contenido energético del tejido muscular. Las observaciones muestran que P. humeralis acepta rápidamente el alimento balanceado alcanzando una sobrevivencia del 95% durante el periodo de evaluación. La concentración muscular de ácidos linoleico y linolénico aumentaron más del 100% en los tres grupos der temperatura. Contrariamente, la concentración de ácidos docosahexaenoico (DHA), araquidónico (ARA), docosopentaenoico (DPA) y eicosapentaenoico (EPA) disminuyeron en 48, 45, 26 y 20%, respectivamente. El contenido energético en músculo aumentó 13% durante el periodo de aclimatación. Se concluye que P. humeralis se adapta rápidamente a las condiciones de cautiverio; sin embargo, el alimento proporcionado debe contener mayores cantidades de ARA, EPA, DPA y DHA

EVALUACIÓN DE FIREWALLS BASADOS EN SOFTWARE LIBRE (FIREWALL EVALUATION BASED ON OPEN SOURCE SOFTWARE)

En este trabajo se propone la evaluación de firewalls basado en software libre GNU/LINUX con las características que les permitan integrarse a una cama de pruebas en la cual se estudiaron, evaluaron y analizaron diversos entornos de red y escenarios de ataque. Los firewalls de software libre son una buena alternativa cuando se trata de brindar seguridad en una red, en este trabajo fueron evaluados cuatro distribuciones Linux que han sido especialmente diseñadas para brindar este servicio. Las herramientas de software libre empleadas demostraron ser las adecuadas para las pruebas realizadas a los diferentes firewalls, de este modo se logró obtener resultados que muestran la factibilidad de ClearOS para ser implementado en la cama de pruebas. También se probó su efectividad al mostrar una buena respuesta en la defensa de los ataques, con y sin la inyección del tráfico de fondo generado por la herramienta iperf.In this work we propose the evaluation of firewalls based on free software GNU / LINUX with the characteristics that allow them to be integrated into a test bed in which various network environments and attack scenarios were studied, evaluated and analyzed. Free software firewalls are a good alternative when it comes to providing security in a network, in this work were evaluated four Linux distributions that have been specially designed to provide this service. The free software tools used, proved to be adequate for the tests carried out on the different firewalls, in this way it was possible to obtain results that show the feasibility of ClearOS to be implemented in the test bed. Its effectiveness was also proven by showing a good response in the defense of attacks, with and without the injection of background traffic generated by the iperf tool

Prevalence, associated factors and outcomes of pressure injuries in adult intensive care unit patients: the DecubICUs study

Funder: European Society of Intensive Care Medicine; doi: http://dx.doi.org/10.13039/501100013347Funder: Flemish Society for Critical Care NursesAbstract: Purpose: Intensive care unit (ICU) patients are particularly susceptible to developing pressure injuries. Epidemiologic data is however unavailable. We aimed to provide an international picture of the extent of pressure injuries and factors associated with ICU-acquired pressure injuries in adult ICU patients. Methods: International 1-day point-prevalence study; follow-up for outcome assessment until hospital discharge (maximum 12 weeks). Factors associated with ICU-acquired pressure injury and hospital mortality were assessed by generalised linear mixed-effects regression analysis. Results: Data from 13,254 patients in 1117 ICUs (90 countries) revealed 6747 pressure injuries; 3997 (59.2%) were ICU-acquired. Overall prevalence was 26.6% (95% confidence interval [CI] 25.9–27.3). ICU-acquired prevalence was 16.2% (95% CI 15.6–16.8). Sacrum (37%) and heels (19.5%) were most affected. Factors independently associated with ICU-acquired pressure injuries were older age, male sex, being underweight, emergency surgery, higher Simplified Acute Physiology Score II, Braden score 3 days, comorbidities (chronic obstructive pulmonary disease, immunodeficiency), organ support (renal replacement, mechanical ventilation on ICU admission), and being in a low or lower-middle income-economy. Gradually increasing associations with mortality were identified for increasing severity of pressure injury: stage I (odds ratio [OR] 1.5; 95% CI 1.2–1.8), stage II (OR 1.6; 95% CI 1.4–1.9), and stage III or worse (OR 2.8; 95% CI 2.3–3.3). Conclusion: Pressure injuries are common in adult ICU patients. ICU-acquired pressure injuries are associated with mainly intrinsic factors and mortality. Optimal care standards, increased awareness, appropriate resource allocation, and further research into optimal prevention are pivotal to tackle this important patient safety threat

Prevalence, associated factors and outcomes of pressure injuries in adult intensive care unit patients: the DecubICUs study

Funder: European Society of Intensive Care Medicine; doi: http://dx.doi.org/10.13039/501100013347Funder: Flemish Society for Critical Care NursesAbstract: Purpose: Intensive care unit (ICU) patients are particularly susceptible to developing pressure injuries. Epidemiologic data is however unavailable. We aimed to provide an international picture of the extent of pressure injuries and factors associated with ICU-acquired pressure injuries in adult ICU patients. Methods: International 1-day point-prevalence study; follow-up for outcome assessment until hospital discharge (maximum 12 weeks). Factors associated with ICU-acquired pressure injury and hospital mortality were assessed by generalised linear mixed-effects regression analysis. Results: Data from 13,254 patients in 1117 ICUs (90 countries) revealed 6747 pressure injuries; 3997 (59.2%) were ICU-acquired. Overall prevalence was 26.6% (95% confidence interval [CI] 25.9–27.3). ICU-acquired prevalence was 16.2% (95% CI 15.6–16.8). Sacrum (37%) and heels (19.5%) were most affected. Factors independently associated with ICU-acquired pressure injuries were older age, male sex, being underweight, emergency surgery, higher Simplified Acute Physiology Score II, Braden score 3 days, comorbidities (chronic obstructive pulmonary disease, immunodeficiency), organ support (renal replacement, mechanical ventilation on ICU admission), and being in a low or lower-middle income-economy. Gradually increasing associations with mortality were identified for increasing severity of pressure injury: stage I (odds ratio [OR] 1.5; 95% CI 1.2–1.8), stage II (OR 1.6; 95% CI 1.4–1.9), and stage III or worse (OR 2.8; 95% CI 2.3–3.3). Conclusion: Pressure injuries are common in adult ICU patients. ICU-acquired pressure injuries are associated with mainly intrinsic factors and mortality. Optimal care standards, increased awareness, appropriate resource allocation, and further research into optimal prevention are pivotal to tackle this important patient safety threat

Correction to: Prevalence, associated factors and outcomes of pressure injuries in adult intensive care unit patients: the DecubICUs study

The original version of this article unfortunately contained a mistake

Bioenergetics of the Peruvian scallops (Argopecten purpuratus) in an environmental context limiting oxygen

Au cours de ces deux dernières décennies, la culture du pétoncle (Argopecten purpuratus) s’est développée dans les baies côtières péruviennes. La disponibilité trophique liée au système d’upwelling est favorable à la production du pétoncle. Cependant, les côtes péruviennes sont également connues pour présenter une forte variabilité environnementale surtout en domaine océanique. Bien que les élevages du pétoncle soient vulnérables aux aléas de production (mortalité, croissance faible), la variabilité environnementale dans les baies côtières du Pérou et ses effets sur la croissance, la reproduction et survie de cette ressource socialement sensible ont été peu étudiées. La baie de Paracas au Pisco-Pérou est une zone traditionnelle de culture du pétoncle où des hauts et des bas productifs liés aux conditions environnementales ont été enregistrés au long de son histoire. Dans le but d’approfondir nos connaissances sur cette problématique, cette étude se pose sous trois approches : (1) l’observation in situ, (2) l’expérimentation en physiologie et (3) la modélisation du bilan énergétique de A. Purpuratus. Un suivi environnemental mené dans la baie de Paracas montre que la variabilité océanographique peut être importante, en particulier pendant l’été. Des variations de température de 8°C et des conditions oxiques allant de la sursaturation à l’anoxie (absence d’oxygène) dans le cours d’une journée ont été observées. L’enregistrement haute fréquence a permis de révéler une exposition chronique, sévère et prolongée de la baie de Paracas aux conditions hypoxiques. Les pétoncles cultivés sur le fond, où l’exposition à l’hypoxie était importante (47% du temps observé) ont montré une croissance et les conditions de reproduction plus faibles. Cependant, au cours de l’été, les événements hypoxiques prolongés et sévères ont touché les deux profondeurs de culture- les pétoncles cultivés en suspension comme sur le fond-, causant des pertes de poids de tissu somatique ainsi que l’arrêt de la reproduction. Durant les expériences en laboratoire, les pétoncles ont montré une importante capacité à réguler leur respiration face à la diminution de la saturation en oxygène jusqu’à 24%. De manière surprenante, nous avons trouvé que cette espèce est capable de maintenir une filtration, quoique diminuée, même à des saturations en oxygène basses (5%). Sur la base des réponses physiologiques du pétoncle face à l’hypoxie et le rendement énergétique moindre du métabolisme anaérobie par rapport au métabolisme aérobie, nous faisons l’hypothèse d’une diminution de l’ensemble du métabolisme à des saturations en oxygène en dessous de la capacité de régulation de l’espèce. Des simulations d’un modèle incluant cette restriction énergétique (sur les flux d’assimilation et de mobilisation de la réserve) en conditions d’hypoxie parviennent à reproduire avec succès les observations de terrain effectuées dans la baie de Paracas : une plus grande exposition à l’hypoxie a pour conséquence une croissance réduite et un arrêt de la reproduction. Alors que le pétoncle possède des adaptations physiologique /métaboliques pour faire face à des conditions limitantes en oxygène, la croissance et la reproduction peuvent être compromises, affectant ainsi la productivité des cultures de cette espèce (cela en fonction de la fréquence, durée et intensité de l’hypoxie). Les résultats des observations, des expériences et des simulations réalisées lors de cette étude fournissent des informations utiles pour mieux gérer la culture de pétoncle péruvien. Sur la base de ces travaux, des estimations de capacité de charge des baies, et des évaluations de zones et profondeurs favorables pour la culture de ces pétoncles pourront être réalisées.During the past two decades, the scallop (Argopecten Purpuratus) culture developed in the Peruvian coastal bays. The trophic availability linked to the upwelling system supports the production scallop. However, the Peruvian coasts are also known to have a high environmental variability especially in oceanic domain. Although scallop farms are vulnerable to production hazards (mortality, low growth), environmental variability in coastal bays of Peru and its effects on growth, reproduction and survival of this socially sensitive resource have been poorly studied. Paracas Bay in Pisco Peru is a traditional farming area where scallop highs and lows in productivity related to environmental conditions were recorded throughout its history. In order increase our knowledge on this issue, this study arises from three approaches : (1) observation in situ, (2) experimental physiology and (3) modelling of the energy budget of A. Purpuratus. An environmental monitoring conducted in the Paracas Bay shows that the oceanographic variability can be important, especially during the summer. Temperature variations of 8°C and oxic conditions ranging from supersaturation to anoxia (absence of oxygen) in the course of a day were observed. The high frequency monitoring has revealed a chronic, severe and prolonged hypoxic condition in Paracas Bay. Scallops grown on the bottom, where exposure to hypoxia was important (47% of the observed time) showed lower growth and reproductions conditions. However, during the summer, prolonged and severe hypoxic events affected both deep culture – scallops grown in suspension and on bottom- causing weight somatic tissue losses and cessation of reproduction. During the laboratory experiments, scallops showed significant ability to regulate their oxygen uptake face to decreased oxygen saturation up to 24%. Surprisingly, we found that this species is able to maintain filtration, although diminished, even at low oxygen saturations (5%). Based on the physiological responses of the Peruvian scallops face to hypoxia and the energy performance aerobic end anaerobic metabolism ; it is hypothesized that there exist a restriction in the energy flow available for metabolism at oxygen saturations below the regulation capacity of the organism. Model simulations including this energy restriction (on assimilation and reserves mobilization fluxes) against hypoxia can reproduce successfully field observations of Paracas Bay : greater exposure to hypoxia results in a reduced growth and reproductive conditions. Although the scallop has physiological adaptations/metabolism to deal with limited oxygen conditions, growth and reproduction can be compromised, affecting culture productivity of this species (according to the frequency, duration and intensity hypoxia). The results of observations, experiments and simulations obtained during this study provide useful information to better manage of Peruvian scallop cultures (ex. Load capacity estimates in the bays, evaluations of adequate areas/depths for culture, etc.)