Interference between weeds and crop: changes in secondary metabolism

Os metabólitos secundários garantem a sobrevivência das plantas em situações adversas. As plantas alteram sua constituição bioquímica a partir do metabolismo primário em resposta à mudanças no ambiente. A produção de metabólitos secundários mitiga os efeitos decorrentes do estresse permitindo o desenvolvimento da planta em situações não ideais. Compostos aleloquímicos são exemplos de metabólitos secundários produzidos por plantas em situação de interferência interespecífica. Quando em estresse por competição, as plantas possuem a capacidade de liberar compostos no ambiente a fim de sinalizar a presença ou inibir o crescimento de plantas vizinhas. As respostas no metabolismo secundário das culturas decorrentes da competição com plantas daninhas alteram a composição química da espécie, resultando em alterações no desenvolvimento e no rendimento. A aplicação de herbicidas também é fonte de alteração no metabolismo secundário pela interrupção de rotas, seja pelo acúmulo de ácidos constituintes ou a formação de compostos não desejados. A revisão atual tem como objetivo mostrar o estado da arte das relações de interferência entre plantas daninhas e as culturas sobre as alterações no metabolismo secundário.Secondary metabolites ensure the survival of plants in adverse situations. Plants change their biochemical constitution from the primary metabolism in response to changes in the environment. The production of secondary metabolites mitigates the effects of stress, allowing the plant development in non-ideal situations. Allelochemical compounds are examples of secondary metabolites produced by plants in situations of interspecific interference. When in competition stress, plants have the ability to release compounds into the environment in order to signal the presence or inhibit the growth of neighboring plants. Secondary metabolism responses of crops resulting from competition with weeds alter the chemical composition of the species, resulting in changes in development and yield. The application of herbicides is also an alteration source in the secondary metabolism by the interruption of routes, either by the accumulation of constituent acids or the formation of unwanted compounds. The current review aims to show the art state of interference relationships between weeds and crops on changes in secondary metabolism

Caracterização mecânica e morfológica de solados produzidos com resíduos de laminados de PVC da indústria calçadista

 A indústria de calçados emprega em seus produtos diversas matérias primas derivadas do setor de plásticos. Um dos mais utilizados é o laminado sintético de PVC, utilizado na construção de cabedais devido à grande versatilidade de cores, estampas e espessuras. O laminado é composto de PVC e de fibra têxtil, normalmente na proporção mássica de 60/40. O corte das peças gera uma grande quantidade de aparas que normalmente são descartadas ou depositadas em aterros sanitários ou ARIPs (Aterros de Resíduos industriais Perigosos). O presente trabalho avalia a viabilidade de incorporação destes resíduos em forma de pó em matriz de PVC virgem para uso em solados nas proporções de 0, 5, 15, 25, 35 pcr (partes por cento de resina), bem como seu desempenho mecânico. Foram avaliadas propriedades físico-mecânicas com tração, dureza shore A e cola-gem, microscopia eletrônica de varredura (MEV) e espectroscopia no infravermelho (FTIR). Os resultados dos ensaios de dureza e tração demonstraram um decréscimo no desempenho na medida em que a concentra-ção de resíduo no compósito aumentou. A força de colagem também apresentou queda na resistência final obtida pelo efeito pull out, confirmado pelas micrografias da superfície de fratura. Pode-se dizer que as mis-turas com resíduos de laminados em pó apresentam características aceitáveis, segundo as normas indicadas e os padrões especificados para a utilização como material para solado. Além disso, a incorporação deste resí-duo diminui a quantidade de material descartado reduzindo o impacto ambiental.Palavras-chave: PVC, compósitos, resíduos de laminado sintético, reciclage

An overview of the Amazonian Aerosol Characterization Experiment 2008 (AMAZE-08)

The Amazon Basin provides an excellent environment for studying the sources, transformations, and properties of natural aerosol particles and the resulting links between biological processes and climate. With this framework in mind, the Amazonian Aerosol Characterization Experiment (AMAZE-08), carried out from 7 February to 14 March 2008 during the wet season in the central Amazon Basin, sought to understand the formation, transformations, and cloud-forming properties of fine- and coarse-mode biogenic aerosol particles, especially as related to their effects on cloud activation and regional climate. Special foci included (1) the production mechanisms of secondary organic components at a pristine continental site, including the factors regulating their temporal variability, and (2) predicting and understanding the cloud-forming properties of biogenic particles at such a site. In this overview paper, the field site and the instrumentation employed during the campaign are introduced. Observations and findings are reported, including the large-scale context for the campaign, especially as provided by satellite observations. New findings presented include: (i) a particle number-diameter distribution from 10 nm to 10 Î1/4m that is representative of the pristine tropical rain forest and recommended for model use; (ii) the absence of substantial quantities of primary biological particles in the submicron mode as evidenced by mass spectral characterization; (iii) the large-scale production of secondary organic material; (iv) insights into the chemical and physical properties of the particles as revealed by thermodenuder-induced changes in the particle number-diameter distributions and mass spectra; and (v) comparisons of ground-based predictions and satellite-based observations of hydrometeor phase in clouds. A main finding of AMAZE-08 is the dominance of secondary organic material as particle components. The results presented here provide mechanistic insight and quantitative parameters that can serve to increase the accuracy of models of the formation, transformations, and cloud-forming properties of biogenic natural aerosol particles, especially as related to their effects on cloud activation and regional climate. © 2010 Author(s)

Hyperoxemia and excess oxygen use in early acute respiratory distress syndrome : Insights from the LUNG SAFE study

Publisher Copyright: © 2020 The Author(s). Copyright: Copyright 2020 Elsevier B.V., All rights reserved.Background: Concerns exist regarding the prevalence and impact of unnecessary oxygen use in patients with acute respiratory distress syndrome (ARDS). We examined this issue in patients with ARDS enrolled in the Large observational study to UNderstand the Global impact of Severe Acute respiratory FailurE (LUNG SAFE) study. Methods: In this secondary analysis of the LUNG SAFE study, we wished to determine the prevalence and the outcomes associated with hyperoxemia on day 1, sustained hyperoxemia, and excessive oxygen use in patients with early ARDS. Patients who fulfilled criteria of ARDS on day 1 and day 2 of acute hypoxemic respiratory failure were categorized based on the presence of hyperoxemia (PaO2 > 100 mmHg) on day 1, sustained (i.e., present on day 1 and day 2) hyperoxemia, or excessive oxygen use (FIO2 ≥ 0.60 during hyperoxemia). Results: Of 2005 patients that met the inclusion criteria, 131 (6.5%) were hypoxemic (PaO2 < 55 mmHg), 607 (30%) had hyperoxemia on day 1, and 250 (12%) had sustained hyperoxemia. Excess FIO2 use occurred in 400 (66%) out of 607 patients with hyperoxemia. Excess FIO2 use decreased from day 1 to day 2 of ARDS, with most hyperoxemic patients on day 2 receiving relatively low FIO2. Multivariate analyses found no independent relationship between day 1 hyperoxemia, sustained hyperoxemia, or excess FIO2 use and adverse clinical outcomes. Mortality was 42% in patients with excess FIO2 use, compared to 39% in a propensity-matched sample of normoxemic (PaO2 55-100 mmHg) patients (P = 0.47). Conclusions: Hyperoxemia and excess oxygen use are both prevalent in early ARDS but are most often non-sustained. No relationship was found between hyperoxemia or excessive oxygen use and patient outcome in this cohort. Trial registration: LUNG-SAFE is registered with ClinicalTrials.gov, NCT02010073publishersversionPeer reviewe

Spontaneous Breathing in Early Acute Respiratory Distress Syndrome: Insights From the Large Observational Study to UNderstand the Global Impact of Severe Acute Respiratory FailurE Study

OBJECTIVES: To describe the characteristics and outcomes of patients with acute respiratory distress syndrome with or without spontaneous breathing and to investigate whether the effects of spontaneous breathing on outcome depend on acute respiratory distress syndrome severity. DESIGN: Planned secondary analysis of a prospective, observational, multicentre cohort study. SETTING: International sample of 459 ICUs from 50 countries. PATIENTS: Patients with acute respiratory distress syndrome and at least 2 days of invasive mechanical ventilation and available data for the mode of mechanical ventilation and respiratory rate for the 2 first days. INTERVENTIONS: Analysis of patients with and without spontaneous breathing, defined by the mode of mechanical ventilation and by actual respiratory rate compared with set respiratory rate during the first 48 hours of mechanical ventilation. MEASUREMENTS AND MAIN RESULTS: Spontaneous breathing was present in 67% of patients with mild acute respiratory distress syndrome, 58% of patients with moderate acute respiratory distress syndrome, and 46% of patients with severe acute respiratory distress syndrome. Patients with spontaneous breathing were older and had lower acute respiratory distress syndrome severity, Sequential Organ Failure Assessment scores, ICU and hospital mortality, and were less likely to be diagnosed with acute respiratory distress syndrome by clinicians. In adjusted analysis, spontaneous breathing during the first 2 days was not associated with an effect on ICU or hospital mortality (33% vs 37%; odds ratio, 1.18 [0.92-1.51]; p = 0.19 and 37% vs 41%; odds ratio, 1.18 [0.93-1.50]; p = 0.196, respectively ). Spontaneous breathing was associated with increased ventilator-free days (13 [0-22] vs 8 [0-20]; p = 0.014) and shorter duration of ICU stay (11 [6-20] vs 12 [7-22]; p = 0.04). CONCLUSIONS: Spontaneous breathing is common in patients with acute respiratory distress syndrome during the first 48 hours of mechanical ventilation. Spontaneous breathing is not associated with worse outcomes and may hasten liberation from the ventilator and from ICU. Although these results support the use of spontaneous breathing in patients with acute respiratory distress syndrome independent of acute respiratory distress syndrome severity, the use of controlled ventilation indicates a bias toward use in patients with higher disease severity. In addition, because the lack of reliable data on inspiratory effort in our study, prospective studies incorporating the magnitude of inspiratory effort and adjusting for all potential severity confounders are required

Identifying associations between diabetes and acute respiratory distress syndrome in patients with acute hypoxemic respiratory failure: an analysis of the LUNG SAFE database

Background: Diabetes mellitus is a common co-existing disease in the critically ill. Diabetes mellitus may reduce the risk of acute respiratory distress syndrome (ARDS), but data from previous studies are conflicting. The objective of this study was to evaluate associations between pre-existing diabetes mellitus and ARDS in critically ill patients with acute hypoxemic respiratory failure (AHRF). Methods: An ancillary analysis of a global, multi-centre prospective observational study (LUNG SAFE) was undertaken. LUNG SAFE evaluated all patients admitted to an intensive care unit (ICU) over a 4-week period, that required mechanical ventilation and met AHRF criteria. Patients who had their AHRF fully explained by cardiac failure were excluded. Important clinical characteristics were included in a stepwise selection approach (forward and backward selection combined with a significance level of 0.05) to identify a set of independent variables associated with having ARDS at any time, developing ARDS (defined as ARDS occurring after day 2 from meeting AHRF criteria) and with hospital mortality. Furthermore, propensity score analysis was undertaken to account for the differences in baseline characteristics between patients with and without diabetes mellitus, and the association between diabetes mellitus and outcomes of interest was assessed on matched samples. Results: Of the 4107 patients with AHRF included in this study, 3022 (73.6%) patients fulfilled ARDS criteria at admission or developed ARDS during their ICU stay. Diabetes mellitus was a pre-existing co-morbidity in 913 patients (22.2% of patients with AHRF). In multivariable analysis, there was no association between diabetes mellitus and having ARDS (OR 0.93 (0.78-1.11); p = 0.39), developing ARDS late (OR 0.79 (0.54-1.15); p = 0.22), or hospital mortality in patients with ARDS (1.15 (0.93-1.42); p = 0.19). In a matched sample of patients, there was no association between diabetes mellitus and outcomes of interest. Conclusions: In a large, global observational study of patients with AHRF, no association was found between diabetes mellitus and having ARDS, developing ARDS, or outcomes from ARDS. Trial registration: NCT02010073. Registered on 12 December 2013

Epidemiology and patterns of tracheostomy practice in patients with acute respiratory distress syndrome in ICUs across 50 countries

Background: To better understand the epidemiology and patterns of tracheostomy practice for patients with acute respiratory distress syndrome (ARDS), we investigated the current usage of tracheostomy in patients with ARDS recruited into the Large Observational Study to Understand the Global Impact of Severe Acute Respiratory Failure (LUNG-SAFE) study. Methods: This is a secondary analysis of LUNG-SAFE, an international, multicenter, prospective cohort study of patients receiving invasive or noninvasive ventilation in 50 countries spanning 5 continents. The study was carried out over 4 weeks consecutively in the winter of 2014, and 459 ICUs participated. We evaluated the clinical characteristics, management and outcomes of patients that received tracheostomy, in the cohort of patients that developed ARDS on day 1-2 of acute hypoxemic respiratory failure, and in a subsequent propensity-matched cohort. Results: Of the 2377 patients with ARDS that fulfilled the inclusion criteria, 309 (13.0%) underwent tracheostomy during their ICU stay. Patients from high-income European countries (n = 198/1263) more frequently underwent tracheostomy compared to patients from non-European high-income countries (n = 63/649) or patients from middle-income countries (n = 48/465). Only 86/309 (27.8%) underwent tracheostomy on or before day 7, while the median timing of tracheostomy was 14 (Q1-Q3, 7-21) days after onset of ARDS. In the subsample matched by propensity score, ICU and hospital stay were longer in patients with tracheostomy. While patients with tracheostomy had the highest survival probability, there was no difference in 60-day or 90-day mortality in either the patient subgroup that survived for at least 5 days in ICU, or in the propensity-matched subsample. Conclusions: Most patients that receive tracheostomy do so after the first week of critical illness. Tracheostomy may prolong patient survival but does not reduce 60-day or 90-day mortality. Trial registration: ClinicalTrials.gov, NCT02010073. Registered on 12 December 2013

Erratum: Global, regional, and national comparative risk assessment of 84 behavioural, environmental and occupational, and metabolic risks or clusters of risks for 195 countries and territories, 1990–2017: a systematic analysis for the Global Burden of Disease Study 2017

Interpretation: By quantifying levels and trends in exposures to risk factors and the resulting disease burden, this assessment offers insight into where past policy and programme efforts might have been successful and highlights current priorities for public health action. Decreases in behavioural, environmental, and occupational risks have largely offset the effects of population growth and ageing, in relation to trends in absolute burden. Conversely, the combination of increasing metabolic risks and population ageing will probably continue to drive the increasing trends in non-communicable diseases at the global level, which presents both a public health challenge and opportunity. We see considerable spatiotemporal heterogeneity in levels of risk exposure and risk-attributable burden. Although levels of development underlie some of this heterogeneity, O/E ratios show risks for which countries are overperforming or underperforming relative to their level of development. As such, these ratios provide a benchmarking tool to help to focus local decision making. Our findings reinforce the importance of both risk exposure monitoring and epidemiological research to assess causal connections between risks and health outcomes, and they highlight the usefulness of the GBD study in synthesising data to draw comprehensive and robust conclusions that help to inform good policy and strategic health planning

ATLANTIC EPIPHYTES: a data set of vascular and non-vascular epiphyte plants and lichens from the Atlantic Forest

Epiphytes are hyper-diverse and one of the frequently undervalued life forms in plant surveys and biodiversity inventories. Epiphytes of the Atlantic Forest, one of the most endangered ecosystems in the world, have high endemism and radiated recently in the Pliocene. We aimed to (1) compile an extensive Atlantic Forest data set on vascular, non-vascular plants (including hemiepiphytes), and lichen epiphyte species occurrence and abundance; (2) describe the epiphyte distribution in the Atlantic Forest, in order to indicate future sampling efforts. Our work presents the first epiphyte data set with information on abundance and occurrence of epiphyte phorophyte species. All data compiled here come from three main sources provided by the authors: published sources (comprising peer-reviewed articles, books, and theses), unpublished data, and herbarium data. We compiled a data set composed of 2,095 species, from 89,270 holo/hemiepiphyte records, in the Atlantic Forest of Brazil, Argentina, Paraguay, and Uruguay, recorded from 1824 to early 2018. Most of the records were from qualitative data (occurrence only, 88%), well distributed throughout the Atlantic Forest. For quantitative records, the most common sampling method was individual trees (71%), followed by plot sampling (19%), and transect sampling (10%). Angiosperms (81%) were the most frequently registered group, and Bromeliaceae and Orchidaceae were the families with the greatest number of records (27,272 and 21,945, respectively). Ferns and Lycophytes presented fewer records than Angiosperms, and Polypodiaceae were the most recorded family, and more concentrated in the Southern and Southeastern regions. Data on non-vascular plants and lichens were scarce, with a few disjunct records concentrated in the Northeastern region of the Atlantic Forest. For all non-vascular plant records, Lejeuneaceae, a family of liverworts, was the most recorded family. We hope that our effort to organize scattered epiphyte data help advance the knowledge of epiphyte ecology, as well as our understanding of macroecological and biogeographical patterns in the Atlantic Forest. No copyright restrictions are associated with the data set. Please cite this Ecology Data Paper if the data are used in publication and teaching events. © 2019 The Authors. Ecology © 2019 The Ecological Society of Americ

Spontaneous Recanalization after Vasectomy

Vasectomy is the method most commonly used in men for voluntary sterilization purposes. We report two cases of early recanalization following vasectomies performed in 1085 men for sterilization purposes at a tertiary public institution between January 2000 and November 2003. Thus, the risk of 0.2% of failure due to early recanalization should be explained and the fertility implications stressed. Written documentation recording the clarification presented at consultation is essential. KEYWORDS: vasectomy, infertility, failure, sterile, sperm INTRODUCTION Of all the methods of contraception, vasectomy is the safest, easiest, cheapest, most effective, and most reliable. It is usually uncomplicated; the discomfort after surgery usually abates promptly and there are generally no sequelae. Further, few patients suffer from bleeding or infection at the vasectomy site. Testicular pain is the most common complication after vasectomy. Although these complications can be serious, the usual conservative management leads to spontaneous cure Vasectomy may fail to result in sterility for three reasons, i.e., by failure to divide either vas, by vasal recanalization caused by the formation of microchannels between the severed ends, and by unrecognized anatomic variation. Although definitions vary among investigators, early failure of the procedure is considered to have occurred when significant numbers of spermatozoa or any motile spermatozoa persist continuously later than 4 months after vasectomy The purpose of our study is to report our experience with vasectomy spontaneous recanalization among 1085 patients treated with vasectomy for sterilization purposes. METHODS Between January 2000 and November 2003, 1085 patients were submitted for vasectomy for sterilization purposes at a tertiary public institution. All patients were over 25 years old or had two or more children. Our institution has a standard protocol for the performance of vasectomy after referral that includes Lucon et al.: Spontaneous Recanalization after Vasectomy TheScientificWorldJOURNAL (2006) 6, 2366-2369 2367 counseling and informed consent. Vasectomy procedure was performed under local anesthesia by a single physician (EDSM). Two 1-cm transversal hemiscrotal incisions were made. A 1-cm vas deferens segment was excised, followed by ligature, but not cauterization, of the cut ends using polypropilene 4-0 transfixed suture. Interposition of fascia was not done. Although the segments excised were not sent for pathological confirmation, the surgeon confirmed it to be vas deferens by passing a suture through its lumen. After vasectomy, patients were advised to maintain their use of contraceptives until they were considered sterile. Sperm samples were obtained before and 2 months after the procedure, and at the 4 th month if the result was other than azoospermia. RESULTS Vasectomy early recanalization occurred in 2 out of 1085 patients (0.2%). The first patient was 40 years old, his wife was 38, and they had four children. The second was 34 years old, his wife 28, and they had two children. A seminal sample was obtained from each patient before the vasectomy procedure and two additional samples were taken 2 and 4 months, respectively, after the surgery. The data of the sperm analysis are summarized i