20 research outputs found
Oceanic and terrestrial sources of continental precipitation
Author Posting. © American Geophysical Union, 2012. This article is posted here by permission of American Geophysical Union for personal use, not for redistribution. The definitive version was published in Reviews of Geophysics 50 (2012): RG4003, doi:10.1029/2012RG000389.The most important sources of atmospheric moisture at the global scale are herein identified, both oceanic and terrestrial, and a characterization is made of how continental regions are influenced by water from different moisture source regions. The methods used to establish source-sink relationships of atmospheric water vapor are reviewed, and the advantages and caveats associated with each technique are discussed. The methods described include analytical and box models, numerical water vapor tracers, and physical water vapor tracers (isotopes). In particular, consideration is given to the wide range of recently developed Lagrangian techniques suitable both for evaluating the origin of water that falls during extreme precipitation events and for establishing climatologies of moisture source-sink relationships. As far as oceanic sources are concerned, the important role of the subtropical northern Atlantic Ocean provides moisture for precipitation to the largest continental area, extending from Mexico to parts of Eurasia, and even to the South American continent during the Northern Hemisphere winter. In contrast, the influence of the southern Indian Ocean and North Pacific Ocean sources extends only over smaller continental areas. The South Pacific and the Indian Ocean represent the principal source of moisture for both Australia and Indonesia. Some landmasses only receive moisture from the evaporation that occurs in the same hemisphere (e.g., northern Europe and eastern North America), while others receive moisture from both hemispheres with large seasonal variations (e.g., northern South America). The monsoonal regimes in India, tropical Africa, and North America are provided with moisture from a large number of regions, highlighting the complexities of the global patterns of precipitation. Some very important contributions are also seen from relatively small areas of ocean, such as the Mediterranean Basin (important for Europe and North Africa) and the Red Sea, which provides water for a large area between the Gulf of Guinea and Indochina (summer) and between the African Great Lakes and Asia (winter). The geographical regions of Eurasia, North and South America, and Africa, and also the internationally important basins of the Mississippi, Amazon, Congo, and Yangtze Rivers, are also considered, as is the importance of terrestrial sources in monsoonal regimes. The role of atmospheric rivers, and particularly their relationship with extreme events, is discussed. Droughts can be caused by the reduced supply of water vapor from oceanic moisture source regions. Some of the implications of climate change for the hydrological cycle are also reviewed, including changes in water vapor concentrations, precipitation, soil moisture, and aridity. It is important to achieve a combined diagnosis of moisture sources using all available information, including stable water isotope measurements. A summary is given of the major research questions that remain unanswered, including (1) the lack of a full understanding of how moisture sources influence precipitation isotopes; (2) the stationarity of moisture sources over long periods; (3) the way in which possible changes in intensity (where evaporation exceeds precipitation to a greater of lesser degree), and the locations of the sources, (could) affect the distribution of continental precipitation in a changing climate; and (4) the role played by the main modes of climate variability, such as the North Atlantic Oscillation or the El NiñoâSouthern Oscillation, in the variability of the moisture source regions, as well as a full evaluation of the moisture transported by low-level jets and atmospheric rivers.Luis Gimeno would like to thank the
Spanish Ministry of Science and FEDER for their partial funding
of this research through the project MSM. A. Stohl was supported
by the Norwegian Research Council within the framework of the
WATERâSIP project. The work of Ricardo Trigo was partially
supported by the FCT (Portugal) through the ENAC project
(PTDC/AAC-CLI/103567/2008).2013-05-0
Mutational Landscape of CEBPA in Mexican Pediatric Acute Myeloid Leukemia Patients: Prognostic Implications
BackgroundIn Mexico, the incidence of acute myeloid leukemia (AML) has increased in the last few years. Mortality is higher than in developed countries, even though the same chemotherapy protocols are used. CCAAT Enhancer Binding Protein Alpha (CEBPA) mutations are recurrent in AML, influence prognosis, and help to define treatment strategies. CEBPA mutational profiles and their clinical implications have not been evaluated in Mexican pediatric AML patients.Aim of the StudyTo identify the mutational landscape of the CEBPA gene in pediatric patients with de novo AML and assess its influence on clinical features and overall survival (OS).Materials and MethodsDNA was extracted from bone marrow aspirates at diagnosis. Targeted massive parallel sequencing of CEBPA was performed in 80 patients.ResultsCEBPA was mutated in 12.5% (10/80) of patients. Frameshifts at the N-terminal region were the most common mutations 57.14% (8/14). CEBPA biallelic (CEBPABI) mutations were identified in five patients. M2 subtype was the most common in CEBPA positive patients (CEBPAPOS) (p = 0.009); 50% of the CEBPAPOS patients had a WBC count > 100,000 at diagnosis (p = 0.004). OS > 1 year was significantly better in CEBPA negative (CEBPANEG) patients (p = 0.0001). CEBPAPOS patients (either bi- or monoallelic) had a significantly lower OS (p = 0.002). Concurrent mutations in FLT3, CSF3R, and WT1 genes were found in CEBPAPOS individuals. Their contribution to poor OS cannot be ruled out.ConclusionCEBPA mutational profiles in Mexican pediatric AML patients and their clinical implications were evaluated for the first time. The frequency of CEBPAPOS was in the range reported for pediatric AML (4.5â15%). CEBPA mutations showed a negative impact on OS as opposed to the results of other studies
Results of Hematopoietic STEM CELL Transplantation for Primary Immunodeficiencies in Children in Mexico: A Multicentric Report
Short- and Mid-term Outcomes of Sleeve Gastrectomy for Morbid Obesity: The Experience of the Spanish National Registry
Los estudios del territorio en perspectiva de la geografĂa escolar
âLos estudios del territorio en perspectiva de la geografĂa escolarâ, tĂtulo del
presente libro donde se recogen algunos de los textos presentados en
la IV ConvenciĂłn Nacional de EducaciĂłn GeogrĂĄfica, organizada por la
Universidad de Córdoba y la Universidad de Antioquia. Evento académico
en el cual se dio el encuentro de docentes de geografĂa y ciencias sociales
para conversar sobre los retos de la educaciĂłn geogrĂĄfica en el paĂs y en
particular acerca de las reflexiones y experiencias dadas en los procesos de
enseñanza de esta disciplina escolar.PresentaciĂłn 15CapĂtulo 1. Territorialidades educativas y educaciones geogrĂĄficas 23CapĂtulo 2. Desarrollos recientes de las didĂĄcticas crĂticas para
una geografĂa escolar comprometida socialmente: reflexiones
desde una prĂĄctica pedagĂłgica. 43CapĂtulo 3. El espacio de la educaciĂłn: cuatro proposiciones
desde el pensamiento clĂĄsico 67CapĂtulo 4: El enfoque cualitativo en la innovaciĂłn de la
didĂĄctica de la geografĂa 91CapĂtulo 5: ResistĂȘncia, territĂłrio e ensino de Geografia:
um debate sobre prĂĄticas e saberes escolares fundamentados
no engajamento social 115CapĂtulo 6: Lectura del territorio con lĂderes comunitarios.
Oportunidades de una ciudadanĂa territorial 139CapĂtulo 7. ImĂĄgenes mentales del territorio en la formaciĂłn
docente de ciencias sociales 161CapĂtulo 8. Perspectivas dialĂ©cticas sobre: territorio usado, lugar
y espacio pĂșblico â privado; categorĂas de anĂĄlisis indispensables
en la enseñanza de la geografĂa escolar 185CapĂtulo 9. EducaciĂłn geogrĂĄfica para los futuros profesionales
en PlaneaciĂłn y Desarrollo Social y su quehacer desde la
perspectiva territorial 205CapĂtulo 10. Implicaciones del discurso de la paz territorial
para la educaciĂłn 227CapĂtulo 11. Del necesario abordaje Ă©tico del territorio en
el trabajo con comunidades vĂctimas del conflicto armado 245CapĂtulo 12. Otra mirada al paisaje en la educaciĂłn rural 277CapĂtulo 13. Percepciones de las transformaciones paisajĂsticas
dadas en las ciénagas del municipio de San Carlos a partir de la
cartografĂa social. 295CapĂtulo 14. El paisaje, mĂĄs allĂĄ de la imagen: apuestas para generar
valores Ă©ticos y estĂ©ticos en la enseñanza de la geografĂa 319CapĂtulo 15. La imagen en la enseñanza de la geografĂa escolar
y la construcciĂłn del pensamiento crĂtico 345CapĂtulo 16. La metamorfosis del paisaje desde un barrio
mirador. Posibilidad de aprender y enseñar la ciudad en
lo cotidiano 359CapĂtulo 17. Estudio del paisaje en La Mojana desde la
percepción de las comunidades. Aportes para la enseñanza
de la geografĂa. 379CapĂtulo 18. Las Olimpiadas Universitarias del Conocimiento
del ĂĄrea de GeografĂa en la Universidad Nacional AutĂłnoma
de MĂ©xico 393CapĂtulo 19. Los aportes de la cartografĂa social a la educaciĂłn
para la paz en las instituciones educativas. 421CapĂtulo 20. Formar pensamiento crĂtico desde la enseñanza de
la geografĂa mediante el estudio del medio geogrĂĄfico rural. 441CapĂtulo 21. FormaciĂłn en didĂĄctica de la geografĂa desde
el semillero de investigaciĂłn 463CapĂtulo 22. GeografĂa escolar una pedagogĂa de la memoria 483CapĂtulo 23. Monumentos con pies: la interacciĂłn en el
Centro de la ciudad 505CapĂtulo 24. La ciudad y su ambiente. Un abordaje a partir
de la salida de campo 52
Early mortality in children with acute lymphoblastic leukemia in a developing country: the role of malnutrition at diagnosis. A multicenter cohort MIGICCL study
Neotropical freshwater fisheries : A dataset of occurrence and abundance of freshwater fishes in the Neotropics
The Neotropical region hosts 4225 freshwater fish species, ranking first among the world's most diverse regions for freshwater fishes. Our NEOTROPICAL FRESHWATER FISHES data set is the first to produce a large-scale Neotropical freshwater fish inventory, covering the entire Neotropical region from Mexico and the Caribbean in the north to the southern limits in Argentina, Paraguay, Chile, and Uruguay. We compiled 185,787 distribution records, with unique georeferenced coordinates, for the 4225 species, represented by occurrence and abundance data. The number of species for the most numerous orders are as follows: Characiformes (1289), Siluriformes (1384), Cichliformes (354), Cyprinodontiformes (245), and Gymnotiformes (135). The most recorded species was the characid Astyanax fasciatus (4696 records). We registered 116,802 distribution records for native species, compared to 1802 distribution records for nonnative species. The main aim of the NEOTROPICAL FRESHWATER FISHES data set was to make these occurrence and abundance data accessible for international researchers to develop ecological and macroecological studies, from local to regional scales, with focal fish species, families, or orders. We anticipate that the NEOTROPICAL FRESHWATER FISHES data set will be valuable for studies on a wide range of ecological processes, such as trophic cascades, fishery pressure, the effects of habitat loss and fragmentation, and the impacts of species invasion and climate change. There are no copyright restrictions on the data, and please cite this data paper when using the data in publications
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, 10â232 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 0â4), 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 (â€1 day), 457 (10·1%) had intermediate weaning (2â6 days), 433 (9·6%) required prolonged weaning (â„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
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, 10â232 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 (â€1 day), 457 (10·1%) had intermediate weaning (2-6 days), 433 (9·6%) required prolonged weaning (â„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
Evaluation of a quality improvement intervention to reduce anastomotic leak following right colectomy (EAGLE): pragmatic, batched stepped-wedge, cluster-randomized trial in 64 countries
Background
Anastomotic leak affects 8 per cent of patients after right colectomy with a 10-fold increased risk of postoperative death. The EAGLE study aimed to develop and test whether an international, standardized quality improvement intervention could reduce anastomotic leaks.
Methods
The internationally intended protocol, iteratively co-developed by a multistage Delphi process, comprised an online educational module introducing risk stratification, an intraoperative checklist, and harmonized surgical techniques. Clusters (hospital teams) were randomized to one of three arms with varied sequences of intervention/data collection by a derived stepped-wedge batch design (at least 18 hospital teams per batch). Patients were blinded to the study allocation. Low- and middle-income country enrolment was encouraged. The primary outcome (assessed by intention to treat) was anastomotic leak rate, and subgroup analyses by module completion (at least 80 per cent of surgeons, high engagement; less than 50 per cent, low engagement) were preplanned.
Results
A total 355 hospital teams registered, with 332 from 64 countries (39.2 per cent low and middle income) included in the final analysis. The online modules were completed by half of the surgeons (2143 of 4411). The primary analysis included 3039 of the 3268 patients recruited (206 patients had no anastomosis and 23 were lost to follow-up), with anastomotic leaks arising before and after the intervention in 10.1 and 9.6 per cent respectively (adjusted OR 0.87, 95 per cent c.i. 0.59 to 1.30; P = 0.498). The proportion of surgeons completing the educational modules was an influence: the leak rate decreased from 12.2 per cent (61 of 500) before intervention to 5.1 per cent (24 of 473) after intervention in high-engagement centres (adjusted OR 0.36, 0.20 to 0.64; P < 0.001), but this was not observed in low-engagement hospitals (8.3 per cent (59 of 714) and 13.8 per cent (61 of 443) respectively; adjusted OR 2.09, 1.31 to 3.31).
Conclusion
Completion of globally available digital training by engaged teams can alter anastomotic leak rates. Registration number: NCT04270721 (http://www.clinicaltrials.gov)