21 research outputs found
Fenología de macroalgas marinas
A loose usage of the term phenology in marine macroalgae studies has caused that other type of events have been recorded as phenological. In order to develop criteria as uniform as possible that allow conducting comparable studies among phycologists, the following definition of phenology is proposed to be adopted: the study of the timing of recurring biological events and the causes of their timing with regard to abiotic and biotic factors. The use of this definition is appropriate in phenological studies of other organisms and encompasses a set of delimitations, based on an analysis of vascular plant phenology. Approaches to gather and analyze phenological variables are suggested. The importance of undertaking long term and large spatial scale studies is highlighted. The relevance of including all reproductive phases of macroalgae life histories is also emphasized in carrying out phenological studies.El uso laxo del término fenología en estudios de macroalgas marinas ha propiciado que se registren como fenológicos a eventos que no son de ese tipo. Para uniformizar criterios que generen estudios ficológicos comparables entre investigadores, se sugiere adoptar la siguiente definición de fenología: estudio de la temporalidad de los eventos biológicos recurrentes y las causas de su empate temporal con respecto a factores abióticos y bióticos. Esta definición es adecuada para aplicarse en estudios fenológicos de otros organismos y contiene una serie de acotamientos, de acuerdo a un análisis de la fenología en plantas vasculares. Se sugieren formas de medición y análisis de eventos fenológicos de macroalgas. Se resalta la importancia de efectuar estudios de largo plazo y a escalas espaciales amplias. De manera similar, se destaca la importancia de considerar las diversas fases del ciclo de vida de las macroalgas en estudios fenológicos
Nuevos registros de macroalgas para el Atlántico mexicano y riqueza florística del Caribe mexicano
Macroalgae samples from a habitat uncommonly analyzed (next to the basal part of live tissue of the corals Acropora palmata and Diploria strigosa), and from a Mexican zone barely known floristically (the southern part of the Mexican Caribbean) were studied. Based on those samples, Corallophila verongiae (Rhodophyta), Derbesia fastigiata (Chlorophyta), and Hincksia onslowensis (Phaeophyta) are recognized as new records for the Mexican Atlantic coast. Similarly, Lophosiphonia obscura (Rhodophyta) is recognized as a new record for the continental coast of the Mexican Atlantic, since the previous solitary record (more than 40 years ago) was from the Alacran reef, in the open ocean, approximately 180 km away from Puerto Progreso, Yucatan. Even though the four macroalgae species were sterile, probably because they have clonal growth and were invading coral tissue, the morphological characters allowed their unequivocal identification. Excepting the first species, the others had not been registered growing on corals. Considering these new records, the total number of macroalgae species registered up to this study for the Mexican Caribbean is 546, including 307 Rhodophyta, 171 Chlorophyta, and 68 Phaeophyta. Both, this tropical Caribbean zone, and the temperate coast of Baja California represent the two richest macroalgae marine zones of Mexico.Se revisaron muestras de macroalgas de un hábitat pocas veces analizado (colindante a la parte basal del tejido vivo de los corales Acropora palmata y Diploria strigosa) y de una zona de México poco conocida florísticamente (parte Sur del Caribe mexicano), con base a lo cual se reporta a Corallophila verongiae (Rhodophyta), Derbesia fastigiata (Chlorophyta) y Hincksia onslowensis (Phaeophyta) como nuevos registros de macroalgas para la costa del Atlántico mexicano. Además, se reporta a Lophosiphonia obscura (Rhodophyta) como nuevo registro para la parte costera continental del Atlántico mexicano, ya que sólo se había registrado hace más de 40 años para Arrecife Alacranes, sitio alejado aproximadamente 180 km al norte de Puerto Progreso, Yucatán. Aunque las especies de macroalgas no presentaron estructuras reproductoras, probablemente por tener crecimiento clonal y estar invadiendo tejido coralino, los caracteres morfológicos permitieron su identificación con certeza. Con excepción de la primera especie, las otras no se habían registrado creciendo sobre corales. Tomando en cuenta estos nuevos registros, el total de especies de macroalgas registradas hasta este estudio para el Caribe mexicano es de 546, incluyendo 307 Rhodophyta, 171 Chlorophyta y 68 Phaeophyta. Esta zona tropical y la costa templada de Baja California conforman las dos zonas florísticas marinas más ricas de México
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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
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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
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
The effect of filamentous turf algal removal on the development of gametes of the coral Orbicella annularis.
Macroalgae and filamentous turf algae (FTA) are abundant on degraded coral reefs, and the reproductive responses of corals may indicate sub-lethal stress under these conditions. The percentage of gametogenic stages (PGS) and the maximum diameter of eggs (MDE; or egg size) of Orbicella annularis were used to evaluate the effect of long- (7-10 months) and short-term (2.5 months) FTA removal (treatments T1 and T2, respectively) at both the beginning (May) and the end (August) of gametogenesis. Ramets (individual lobes of a colony) surrounded by FTA (T3) or crustose coralline algae (CCA; T4) were used as controls. The removal of FTA enhanced the development of gametes (i.e., a larger and higher percentage of mature gametes (PMG)) of O. annularis for T1 vs. T3 ramets in May and T1 and T2 vs. T3 ramets in August. Similar values of PGS and MDE between gametes from T3 and T4 in both May and August were unexpected because a previous study had shown that the same ramets of T4 (with higher tissue thickness, chlorophyll a cm-2 and zooxanthellae density and lower mitotic index values) were less stressed than ramets of T3. Evaluating coral stress through reproduction can reveal more sensitive responses than other biological parameters; within reproductive metrics, PGS can be a better stress indicator than egg size. The presence of turf algae strongly impacted the development of gametes and egg size (e.g., PMG in ramets with FTA removal increased almost twofold in comparison with ramets surrounded by FTA in August), most likely exerting negative chronic effects in the long run due to the ubiquity and permanence of turf algae in the Caribbean. These algae can be considered a stressor that affects coral sexual reproduction. Although the effects of turf algae on O. annularis are apparently less severe than those of other stressors, the future of this species is uncertain because of the combined impacts of these effects, the decline of O. annularis populations and the almost complete lack of recruitment
Biological responses of the coral Montastraea annularis to the removal of filamentous turf algae.
Coral reef degradation increases coral interactions with filamentous turf algae (FTA) and macroalgae, which may result in chronic stress for the corals. We evaluated the effects of short (2.5 month) and long (10 month) periods of FTA removal on tissue thickness (TT), zooxanthellae density (ZD), mitotic index (MI), and concentration of chlorophyll a (Chl a) in Montastraea annularis at the beginning and end of gametogenesis. Ramets (individual lobes within a colony) consistently surrounded by FTA and ramets surrounded by crustose coralline algae (CCA) were used as controls. FTA removal reduced coral stress, indicated by increased TT and ZD and lower MI. The measured effects were similar in magnitude for the short and long periods of algal removal. Ramets were more stressed at the end of gametogenesis compared with the beginning, with lower ZD and Chl a cm(-2), and higher MI. However, it was not possible to distinguish the stress caused by the presence of FTA from that caused by seasonal changes in seawater temperature. Ramets surrounded by CCA showed less stress in comparison with ramets surrounded by FTA: with higher TT, Chl a cm(-2) and ZD, and lower MI values. Coral responses indicated that ramets with FTA suffered the most deleterious effects and contrasted with those measured in ramets surrounded by CCA. According to published studies and our observations, there could be at least six mechanisms associated to FTA in the stress caused to M. annularis by FTA. Owing to the high cover of FTA (in contrast to macroalgae and CCA) in the Caribbean, the chronic stress, the overgrowth and mortality that this functional algal group can cause on M. annularis species complex, a further decline of this important reef-building coral in the Caribbean is expected
<i>Orbicella annularis</i> gametogenesis.
<p>A) Stage I oocyte located between the mesoglea (m) and the gastrodermis (g); B) Stage II oocyte; C) Stage IV oocyte (next to a Stage III spermary); D) Stage V oocyte with nucleus (N) and nucleolus (red small circle) in its periphery; E) Stage III spermary with spermatocytes surrounding its periphery; and F) Stage IV spermary with spermatocytes homogeneously distributed. Microphotographs: NP Cetz-Navarro. Scales: A = 10 μm; B = 20 μm; C = 75 μm; D and E = 50 μm; F = 25 μm.</p
Experimental design used for <i>Orbicella annularis</i> ramets, with four treatments.
<p>The experiment included <i>O</i>. <i>annularis</i> ramets with filamentous turf algae removal from their periphery (FTA removal), ramets surrounded by FTA (FTA presence), and ramets with coralline crustose algae surrounding coral tissue (CCA presence). Experimental ramets were collected in May and August 2010 (arrows) to evaluate the development of gametes at the beginning (first four rows of treatments) and the end (last four rows of treatments) of <i>O</i>. <i>annularis</i> gametogenesis, respectively. Treatments: T1 = ramets with long-term FTA removal during 7 and 10 months before the beginning (T1M) and the end (T1A) of gametogenesis, respectively; T2 = ramets with short-term FTA removal during 2.5 months before the beginning (T2M) and the end (T2A) of gametogenesis; T3 = control ramets in permanent contact with FTA (T3M and T3A); and T4 = control ramets permanently surrounded by CCA (T4M and T4A).</p
Mean percentage values of gamete stages of <i>Orbicella annularis</i> during gametogenesis.
<p>A) Gamete stages found in May, the beginning of gametogenesis: Stage I oocytes (SI o) + Stage II oocytes (SII o) = 100%, and B) gamete stages found in August, the end of gametogenesis: Stage IV oocytes (SIV o) + Stage V oocytes (SV o) + Stage III spermaries (SIII s) + Stage IV spermaries (SIV s) = 100%. Treatments: T1) ramets with long-term removal of FTA, T2) ramets with short-term removal of FTA, T3) control ramets always surrounded by FTA, and T4) control ramets always surrounded by CCA. Lower-case letters (a-b for May, and a-b and c-d for August) above pair of bars indicate treatments that were significantly different (P ≤ 0.005). n = 7 collected ramets per treatment on each date.</p