Current water quality guidelines across North America and Europe do not protect lakes from salinization

Human-induced salinization caused by the use of road deicing salts, agricultural practices, mining operations, and climate change is a major threat to the biodiversity and functioning of freshwater ecosystems. Yet, it is unclear if freshwater ecosystems are protected from salinization by current water quality guidelines. Leveraging an experimental network of land-based and in-lake mesocosms across North America and Europe, we tested how salinization-indicated as elevated chloride (C-) concentration-will affect lake food webs and if two of the lowest Cl- thresholds found globally are sufficient to protect these food webs. Our results indicated that salinization will cause substantial zooplankton mortality at the lowest Cl- thresholds established in Canada (120 mg Cl-/L) and the United States (230 mg Cl-/L) and throughout Europe where Cl- thresholds are generally higher. For instance, at 73% of our study sites, Cl- concentrations that caused a >= 50% reduction in cladoceran abundance were at or below Cl thresholds in Canada, in the United States, and throughout Europe. Similar trends occurred for copepod and rotifer zooplankton. The loss of zooplankton triggered a cascading effect causing an increase in phytoplankton biomass at 47% of study sites. Such changes in lake food webs could alter nutrient cycling and water clarity and trigger declines in fish production. Current Cl- thresholds across North America and Europe clearly do not adequately protect lake food webs. Water quality guidelines should be developed where they do not exist, and there is an urgent need to reassess existing guidelines to protect lake ecosystems from human-induced salinization.Peer reviewe

Lake salinization drives consistent losses of zooplankton abundance and diversity across coordinated mesocosm experiments

Human-induced salinization increasingly threatens inland waters; yet we know little about the multifaceted response of lake communities to salt contamination. By conducting a coordinated mesocosm experiment of lake salinization across 16 sites in North America and Europe, we quantified the response of zooplankton abundance and (taxonomic and functional) community structure to a broad gradient of environmentally relevant chloride concentrations, ranging from 4 to ca. 1400 mg Cl- L-1. We found that crustaceans were distinctly more sensitive to elevated chloride than rotifers; yet, rotifers did not show compensatory abundance increases in response to crustacean declines. For crustaceans, our among-site comparisons indicate: (1) highly consistent decreases in abundance and taxon richness with salinity; (2) widespread chloride sensitivity across major taxonomic groups (Cladocera, Cyclopoida, and Calanoida); and (3) weaker loss of functional than taxonomic diversity. Overall, our study demonstrates that aggregate properties of zooplankton communities can be adversely affected at chloride concentrations relevant to anthropogenic salinization in lakes.Peer reviewe

Widespread variation in salt tolerance within freshwater zooplankton species reduces the predictability of community-level salt tolerance

The salinization of freshwaters is a global threat to aquatic biodiversity. We quantified variation in chloride (Cl-) tolerance of 19 freshwater zooplankton species in four countries to answer three questions: (1) How much variation in Cl- tolerance is present among populations? (2) What factors predict intraspecific variation in Cl- tolerance? (3) Must we account for intraspecific variation to accurately predict community Cl- tolerance? We conducted field mesocosm experiments at 16 sites and compiled acute LC(50)s from published laboratory studies. We found high variation in LC(50)s for Cl- tolerance in multiple species, which, in the experiment, was only explained by zooplankton community composition. Variation in species-LC50 was high enough that at 45% of lakes, community response was not predictable based on species tolerances measured at other sites. This suggests that water quality guidelines should be based on multiple populations and communities to account for large intraspecific variation in Cl- tolerance.Peer reviewe

Recomendaciones generales para mejorar la práctica de la ortopedia

Orthopedics is one of the specialties with more number of dissents received at CONAMED (National Medical Arbitration Commission of México). The cases related to this specialty were analyzed. Results: 28% of involved doctors didn�t have any board certification; deforming and degenerative were the main causes of application of service; the most frequent dissent reasons were delay of medical attention and delay or negation of diagnostics auxiliaries. The communication problems in the doctor-patient relationship reached 87.3% of the cases. The most outstanding deviation by frequency was a deficient diagnosis plan (40.9%). A group of prestigious specialist analyzed those results and emitted by Consensus these General Recommendations to improve the Practice of Orthopedics: 1) Have the board certification and re-certifications indispensable to exercise Orthopedics specialty, 2) Maintain appropriate medical communication with the patient and its responsible relative, 3) Assure the understanding and acceptance of the proposed diagnostic and therapeutic procedures, 4) Value the patient integrally, to structure diagnostic and establish treatments or opportune therapeutic measures, 5) Assure from the first contact the injured patient�s integral valuation, 6) Define and meditate with opportunity the handling for each case. They also emitted Specific Recommendations for the patient�s attention with Low Back Pain and with Sprain in extremities, because these were the most frequent sufferings found in the dissents.La Ortopedia es una de las especialidades con mayor número de inconformidades ante CONAMED. Se analizaron los casos relacionados a esta especialidad y se encontró que 28% de los médicos involucrados no contaban con ninguna certificación. Los padecimientos deformantes y degenerativos fueron las principales causas de solicitud de servicio. Los motivos de inconformidad más frecuentes fueron diferimiento de la atención, diferimiento y/o negación de auxiliares de diagnóstico. Los problemas de comunicación en la relación médico-paciente alcanzaron 87.3% de los casos. Se detectó que la desviación más relevante por frecuencia fue un protocolo de estudio deficiente (40.9%). Un grupo de prestigiados médicos especialistas analizó estos resultados y emitió por consenso las Recomendaciones Generales para mejorar la Práctica de la Ortopedia: 1) Contar con las certificación y recertificaciones indispensables para ejercer la especialidad de ortopedia, 2) Mantener comunicación médica adecuada con el paciente y su familiar responsable, 3) Asegurar la comprensión y la aceptación de los procedimientos diagnósticos y terapéuticos propuestos, 4) Valorar integralmente al paciente, estructurar diagnósticos y establecer tratamientos o medidas terapéuticas oportunas, 5) Asegurar desde el primer contacto la valoración integral del paciente lesionado, 6) Definir y reflexionar con oportunidad el manejo para cada caso. Emitieron también Recomendaciones Específicas para la atención del paciente con Lumbalgia y con Esguince en extremidades, pues estos fueron los padecimientos más frecuentes encontrados en las inconformidades