Nuevos registros de ácaros oribátidos (Acari: Oribatida) para la Argentina New records of oribatid mites (Acari: Oribatida) from Argentina

La presente nota da a conocer nuevos registros de ácaros oribátidos para Argentina, tanto a nivel específico como genérico: Aphelacarus Grandjean, Aphelacarus acarinus acarinus (Berlese), Trimalaconothrus (Tyrphonothrus) maior (Berlese), Nothrus anauniensis Canestrini y Fanzago, Nothrus becki Balogh y Mahunka, Tectocepheus minor Berlese, Cultroribula zicsii Balogh y Mahunka, Ceratobates Balogh & Mahunka, Ceratobates fornerisae Pérez- Iñigo y Baggio y Totobates discifer Hammer. El material fue recolectado en el Vivero Dunícola «Florentino Ameghino», Miramar, Sudeste de la provincia de Buenos Aires, Argentina.<br>This paper provides new records for oribatid mites from Argentina both at species and genus level: Aphelacarus Grandjean, Aphelacarus acarinus acarinus (Berlese), Trimalaconothrus (Tyrphonothrus) maior (Berlese), Nothrus anauniensis Canestrini & Fanzago, Nothrus becki Balogh & Mahunka, Tectocepheus minor Berlese, Cultroribula zicsii Balogh & Mahunka, Ceratobates Balogh & Mahunka, Ceratobates fornerisae Pérez-Iñigo & Baggio and Totobates discifer Hammer. Specimens were collected in the Vivero Dunícola «Florentino Ameghino», Miramar City, South-east of Buenos Aires province, Argentina

Nuevos registros de ácaros oribátidos (Acari: Oribatida) para la región Pampeana, Buenos Aires, Argentina

La presente nota da a conocer nueve registros nuevos de ácaros oribátidos para Argentina y dos registros fuera de la localidad tipo. Las nuevas citas pertenecen a los géneros Stomacarus, Adelphacarus, Beklemishevia, Epilohmannia, Acrotritia, Anderemaeus, Pseudotocepheus, Teratoppia, Eupelops y Allogalumna. Los especímenes fueron colectados a partir de material de las localidades de Magdalena, Mar Chiquita y Mar del Plata

Nuevos registros de ácaros oribátidos (Acari: Oribatida) para la región Pampeana, Buenos Aires, Argentina New records of oribatid mites (Acari: Oribatida) from the Pampean Region, Buenos Aires, Argentina

La presente nota da a conocer nueve registros nuevos de ácaros oribátidos para Argentina y dos registros fuera de la localidad tipo. Las nuevas citas pertenecen a los géneros Stomacarus, Adelphacarus, Beklemishevia, Epilohmannia, Acrotritia, Anderemaeus, Pseudotocepheus, Teratoppia, Eupelops y Allogalumna. Los especímenes fueron colectados a partir de material de las localidades de Magdalena, Mar Chiquita y Mar del Plata.This paper presents nine new records of oribatid mites for Argentina and two new records outside of the type locality. The new records correspond to the following genera: Stomacarus, Adelphacarus, Beklemishevia, Epilohmannia, Acrotritia, Anderemaeus, Pseudotocepheus, Teratoppia, Eupelops and Allogalumna. Specimens were collected in the localities Magdalena, Mar Chiquita and Mar del Plata

Microartrópodos como indicadores de disturbio antrópico en entisoles del área recreativa de Miramar, Argentina Microarthropods as indicators of anthropic disturbance in entisols in a recreational area of Miramar, Argentina

En áreas recreativas el tránsito humano provoca alteraciones en el horizonte superficial del suelo, destruyendo parte o la totalidad de éste, reduciendo la porosidad y modificando el microambiente edáfico. La mesofauna edáfica, por habitar principalmente en los horizontes superficiales del suelo, resulta ser un buen indicador de este impacto antrópico. Se evaluó la distribución de ácaros oribátidos y colémbolos de suelo frente al impacto del tránsito humano en el área recreativa del Vivero Dunícola "Florentino Ameghino" de Miramar, Buenos Aires, Argentina. Se consideraron tres zonas de impacto: máximo, medio y mínimo. Se extrajeron los microartrópodos y se determinaron hasta nivel de especie colémbolos y oribátidos. Se calculó riqueza específica, diversidad y paridad por sitio y horizonte. Se realizó un análisis de correspondencia y se elaboró un índice de impacto teniendo en cuenta los diferentes horizontes y la frecuencia de especies. Se hallaron 29 especies de ácaros oribátidos y 19 especies de colémbolos. La diversidad (H´) fue significativamente diferente entre los sitios de máximo y de mínimo impacto. El análisis factorial de correspondencia definió tres grupos de acuerdo al grado de alteración de los horizontes superficiales y las características pedológicas (horizonte orgánico o mineral). El índice de impacto (II M) en la zona de mayor tránsito fue II M=9 mientras que en la de mínimo impacto fue II M<1. Los resultados demostraron que la comunidad de microartrópodos considerada resultó ser un buen indicador de impacto antrópico y adecuada para bioevaluar el estado del área estudiada.<br>Human trampling in recreational areas causes alterations in the soil surface horizon, partially or totally disrupting soil structure, reducing porosity and modifying the edaphic microenvironment. Soil mesofauna, is a good indicator of this human impact since it inhabits mainly soil surface horizons. We evaluated the changes in edaphic oribatid mite (Acari) and springtail (Collembola) communities sufferering from the impact of human trampling in the recreational area of Vivero Dunícola "Florentino Ameghino" Miramar, in the Province of Buenos Aires, Argentina. Three impact areas were considered: maximum, medium and minimum. Collembola and oribatid were determined to species level. Species richness, diversity and parity by site and horizon were calculated. A correspondence analysis was carried out and an impact index elaborated taking into account the different horizons and species frequencies. Twenty-nine species of oribatid mites and 19 species of Collembola were found. Diversity (H´) was significantly different between the maximum and minimum impact sites. Factorial Correspondence Analysis defined three groups in terms of degree of alteration of the surfacel horizon and pedological characteristics (organic or mineral horizons). The value of the impact index (II M) in the maximum trampling area was II M=9 while in that of minimum impact it was II M < 1. The results support the usefulness of the microarthropod community as an indicator of human impact and their suitability for bioevaluating the state of the study area

Phylum Arthropoda: Introduction and Arachnida

Spiders (Order Araneae) are among the most familiar arthropods to people, besides being very abundant in most environments. However, most spiders live on strictly defined environments, and the limitations are usually set by physical conditions, such as temperature, humidity, wind, and light intensity as well as by biological factors, such as vegetation structure, prey availability and predators (Foelix, 2011). Freshwater spiders live on specific habitats near but not in the water where they can walk on its surface and dive after tadpoles or small fishes. Neotropical spiders associated with freshwater are quite diverse, and are found in four families: Ctenidae, Lycosidae, Pisauridae and Trechaleidae, all within Lycosoidea. The families Ctenidae, Lycosidae and Pisauridae have a few freshwater representatives including Ancylometes (Ctenidae) and nursery web spiders (Pisauridae). The most diverse and widespread family associated with Neotropical freshwater environments is Trechaleidae, with 15 genera (World Spider Catalog, 2017) found almost exclusively in the Neotropics. Spiders in this family live in vegetation near the margins of rocky streams and small rivers (Carico, 1993). Aquatic spiders possess flexible tarsi that maybe helpful in locomotion on the surface of the water during foraging. They also can crawl underwater to capture prey.Fil: Rogers, D. Christopher. University of Kansas; Estados UnidosFil: Fredes, Natalia A.. No especifíca;Fil: Martínez, Pablo A.. No especifíca;Fil: Ferretti, Nelson Edgardo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto de Ciencias Biológicas y Biomédicas del Sur. Universidad Nacional del Sur. Departamento de Biología, Bioquímica y Farmacia. Instituto de Ciencias Biológicas y Biomédicas del Sur; ArgentinaFil: Pompozzi, Gabriel Alejandro. Universidad de la República. Facultad de Ciencias; Uruguay. Universidad Nacional del Sur; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Rogério Pepato, Almir. No especifíca;Fil: da Silva Conceição, Pedro Henrique. No especifíca

Undergraduate teaching of evolution in Chile: more than natural selection [Enseñanza de la evolución en Chile: más que selección natural]

In a recent commentary, Nespolo (2003) makes reference to his personal experience as exattendant to the course of evolution imparted by Dr. Humberto Maturana and Dr. Jorge Mpodozis at the Facultad de Ciencias of the Universidad de Chile to construct a negative criticism of Chilean undergraduate teaching of evolution. As ex-attendants of the mentioned course of evolution we have had an experience that is directly comparable to that of Dr. Nespolo. Here we wish to point out our opinion regarding this course, which is markedly different. First, it is a caricature to state that in this course natural selection is taught as being wrong. A serious and critical revision of natural selection, the synthetic theory, and evolutionary ecology is a fundamental part of the course. These and other topics are presented by researchers from those fields, such as Drs. Germán Manríquez and Rodrigo Medel. The scientific contributions of both researchers receive positive comments in Nespolo (2003)

Undergraduate teaching of evolution in Chile: more than natural selection [Enseñanza de la evolución en Chile: más que selección natural]

In a recent commentary, Nespolo (2003) makes reference to his personal experience as exattendant to the course of evolution imparted by Dr. Humberto Maturana and Dr. Jorge Mpodozis at the Facultad de Ciencias of the Universidad de Chile to construct a negative criticism of Chilean undergraduate teaching of evolution. As ex-attendants of the mentioned course of evolution we have had an experience that is directly comparable to that of Dr. Nespolo. Here we wish to point out our opinion regarding this course, which is markedly different. First, it is a caricature to state that in this course natural selection is taught as being wrong. A serious and critical revision of natural selection, the synthetic theory, and evolutionary ecology is a fundamental part of the course. These and other topics are presented by researchers from those fields, such as Drs. Germán Manríquez and Rodrigo Medel. The scientific contributions of both researchers receive positive comments in Nespolo (2003)

Weaning from mechanical ventilation in intensive care units across 50 countries (WEAN SAFE): a multicentre, prospective, observational cohort study

Background: Current management practices and outcomes in weaning from invasive mechanical ventilation are poorly understood. We aimed to describe the epidemiology, management, timings, risk for failure, and outcomes of weaning in patients requiring at least 2 days of invasive mechanical ventilation. Methods: WEAN SAFE was an international, multicentre, prospective, observational cohort study done in 481 intensive care units in 50 countries. Eligible participants were older than 16 years, admitted to a participating intensive care unit, and receiving mechanical ventilation for 2 calendar days or longer. We defined weaning initiation as the first attempt to separate a patient from the ventilator, successful weaning as no reintubation or death within 7 days of extubation, and weaning eligibility criteria based on positive end-expiratory pressure, fractional concentration of oxygen in inspired air, and vasopressors. The primary outcome was the proportion of patients successfully weaned at 90 days. Key secondary outcomes included weaning duration, timing of weaning events, factors associated with weaning delay and weaning failure, and hospital outcomes. This study is registered with ClinicalTrials.gov, NCT03255109. Findings: Between Oct 4, 2017, and June 25, 2018, 10 232 patients were screened for eligibility, of whom 5869 were enrolled. 4523 (77·1%) patients underwent at least one separation attempt and 3817 (65·0%) patients were successfully weaned from ventilation at day 90. 237 (4·0%) patients were transferred before any separation attempt, 153 (2·6%) were transferred after at least one separation attempt and not successfully weaned, and 1662 (28·3%) died while invasively ventilated. The median time from fulfilling weaning eligibility criteria to first separation attempt was 1 day (IQR 0-4), and 1013 (22·4%) patients had a delay in initiating first separation of 5 or more days. Of the 4523 (77·1%) patients with separation attempts, 2927 (64·7%) had a short wean (≤1 day), 457 (10·1%) had intermediate weaning (2-6 days), 433 (9·6%) required prolonged weaning (≥7 days), and 706 (15·6%) had weaning failure. Higher sedation scores were independently associated with delayed initiation of weaning. Delayed initiation of weaning and higher sedation scores were independently associated with weaning failure. 1742 (31·8%) of 5479 patients died in the intensive care unit and 2095 (38·3%) of 5465 patients died in hospital. Interpretation: In critically ill patients receiving at least 2 days of invasive mechanical ventilation, only 65% were weaned at 90 days. A better understanding of factors that delay the weaning process, such as delays in weaning initiation or excessive sedation levels, might improve weaning success rates. Funding: European Society of Intensive Care Medicine, European Respiratory Society