Effects of natural mortality on the yield per recruit models

Dissertação de Mestrado, Estudos Integrados dos Oceanos, 22 de Janeiro de 2016, Universidade dos Açores.A mortalidade natural (M) é um dos mais importantes parâmetros utilizado nos modelos de captura por recruta e é geralmente assumido como constante ao longo do tempo. No entanto, M é fortemente relacionada com a idade, comprimento ou peso. Este estudo analisa pela primeira vez os efeitos da mortalidade natural na estimativa da captura por recruta para o stock de Goraz (Pagellus bogaraveo) no Arquipélago dos Açores. [...]. São discutidas implicações destas variações para a avaliação do recurso.ABSTRACT: Natural mortality (M) is one of the most important parameter used on the Yield Per Recruit models and is commonly assumed as constant over time. However, M is strongly related to age, length or weight. This study analyses for the first time the effects of natural mortality in the yield per recruit estimates for the red black spot seabream (Pagellus bogaraveo) stock from the Azores archipelago. [...]. Implications of these variations for the stock assessment are discussed

Estimates of biomass and potential yield for the deep-water red crab, Chaceon affinis and the toothed rock crab, Cancer bellianus (Decapoda: Brachyura) off the Azores (Mid-North Atlantic)

Available information on the deep-water red crab, Chaceon affinis and the toothed rock crab, Cancer bellianus, resulting from exploratory research surveys and commercial fishing experiments carried out in the Azorean Exclusive Economic Zone (EEZ), were summarized to estimate the biomass and potential yield (Maximum Sustainable Yield – MSY) for both fishery resources. The fishery potential was estimated through empirical methods usually applied when available information is scarce in line with the precautionary approach principle. Results suggest modest MSY values (considered as precautionary Total Allowable Catch – TAC), around 2,205 t for the deep-water red crab (2,159 t year-1 at seamounts and 46 t year-1 at coastal areas), and 471 t for the toothed rock crab (281 t year-1 at offshore seamounts and 189 t year-1 at coastal areas). Considering the limited available data and high uncertainty associated with these estimations, it is suggested that only a reduced number of vessels should be allowed to fish in the aggregated areas, namely coastal and seamount areas. The exploitation of these resources should be started in a very limited way followed by an ad hoc observer programme, aiming to collect reliable data that will allow, if it is the case, to raise in the future the exploitation level in a gradual and sustainable way.Régis Santos was supported by the IMAR Institute of Marine Research, through a post-doc fellowship (ref. IMAR/DEMERSAIS/001-2018). Wendell Silva was funded by the IMAR Instituto do Mar, through a scholarship (ref. IMAR/UNI/MAR/04292/2013 MARE/001-2018). Ana Novoa-Pabon was funded by an FCT Ph.D. fellowship (ref. SFRH/BD/124720/2016).info:eu-repo/semantics/publishedVersio

Estimates of biomass and potential yield for the deep-water red crab, Chaceon affinis and the toothed rock crab, Cancer bellianus (Decapoda: Brachyura) off the Azores (Mid-North Atlantic)

Available information on the deep-water red crab, Chaceon affinis and the toothed rock crab, Cancer bellianus, resulting from exploratory research surveys and commercial fishing experiments carried out in the Azorean Exclusive Economic Zone (EEZ), were summarized to estimate the biomass and potential yield (Maximum Sustainable Yield – MSY) for both fishery resources. The fishery potential was estimated through empirical methods usually applied when available information is scarce in line with the precautionary approach principle. Results suggest modest MSY values (considered as precautionary Total Allowable Catch – TAC), around 2,205 t for the deep-water red crab (2,159 t year-1 at seamounts and 46 t year-1 at coastal areas), and 471 t for the toothed rock crab (281 t year-1 at offshore seamounts and 189 t year-1 at coastal areas). Considering the limited available data and high uncertainty associated with these estimations, it is suggested that only a reduced number of vessels should be allowed to fish in the aggregated areas, namely coastal and seamount areas. The exploitation of these resources should be started in a very limited way followed by an ad hoc observer programme, aiming to collect reliable data that will allow, if it is the case, to raise in the future the exploitation level in a gradual and sustainable way.Régis Santos was supported by the IMAR Institute of Marine Research, through a post-doc fellowship (ref. IMAR/DEMERSAIS/001-2018). Wendell Silva was funded by the IMAR Instituto do Mar, through a scholarship (ref. IMAR/UNI/MAR/04292/2013 MARE/001-2018). Ana Novoa-Pabon was funded by an FCT Ph.D. fellowship (ref. SFRH/BD/124720/2016).info:eu-repo/semantics/publishedVersio

Impact of COVID-19 on cardiovascular testing in the United States versus the rest of the world

Objectives: This study sought to quantify and compare the decline in volumes of cardiovascular procedures between the United States and non-US institutions during the early phase of the coronavirus disease-2019 (COVID-19) pandemic. Background: The COVID-19 pandemic has disrupted the care of many non-COVID-19 illnesses. Reductions in diagnostic cardiovascular testing around the world have led to concerns over the implications of reduced testing for cardiovascular disease (CVD) morbidity and mortality. Methods: Data were submitted to the INCAPS-COVID (International Atomic Energy Agency Non-Invasive Cardiology Protocols Study of COVID-19), a multinational registry comprising 909 institutions in 108 countries (including 155 facilities in 40 U.S. states), assessing the impact of the COVID-19 pandemic on volumes of diagnostic cardiovascular procedures. Data were obtained for April 2020 and compared with volumes of baseline procedures from March 2019. We compared laboratory characteristics, practices, and procedure volumes between U.S. and non-U.S. facilities and between U.S. geographic regions and identified factors associated with volume reduction in the United States. Results: Reductions in the volumes of procedures in the United States were similar to those in non-U.S. facilities (68% vs. 63%, respectively; p = 0.237), although U.S. facilities reported greater reductions in invasive coronary angiography (69% vs. 53%, respectively; p < 0.001). Significantly more U.S. facilities reported increased use of telehealth and patient screening measures than non-U.S. facilities, such as temperature checks, symptom screenings, and COVID-19 testing. Reductions in volumes of procedures differed between U.S. regions, with larger declines observed in the Northeast (76%) and Midwest (74%) than in the South (62%) and West (44%). Prevalence of COVID-19, staff redeployments, outpatient centers, and urban centers were associated with greater reductions in volume in U.S. facilities in a multivariable analysis. Conclusions: We observed marked reductions in U.S. cardiovascular testing in the early phase of the pandemic and significant variability between U.S. regions. The association between reductions of volumes and COVID-19 prevalence in the United States highlighted the need for proactive efforts to maintain access to cardiovascular testing in areas most affected by outbreaks of COVID-19 infection

Robust identification of potential habitats of a rare demersal species (blackspot seabream) in the Northeast Atlantic

Species distribution models (SDM) are commonly used to identify potential habitats. When fitting them to heterogeneous, opportunistically collated presence/absence data, imbalance in the number of presence and absence observations often occurs, which could influence results. To robustly identify potential habitats for blackspot seabream (Pagellus bogaraveo) throughout its distribution area in the Northeast Atlantic and the western Mediterranean Sea, we used an ensemble species distribution modelling (eSDM) approach, modelling gridded presence–absence data with environmental predictors for two types of occurrence data sets. The first data set displayed the observed unbalanced spatially heterogeneous presence/absence ratio and the second a balanced presence/absence ratio. The data covered the full distribution area, including the European Atlantic shelf, the Azorean region and the Western Mediterranean Sea. Across these regions, populations display variable status. The main environmental predictors for potential habitats were bathymetry and annual maximum SST. The fitted ensemble compromise (eSDM) was projected over the whole grid to create a habitat suitability map. This map exhibited higher probabilities of presence for the balanced-ratio data set. A binary presence–absence map was then generated using optimized presence probability thresholds for four validation indices. Using the true skill statistic to optimize the threshold, the surface areas of the binary presence–absence map was 53% smaller for the balanced data set than for the observed unbalanced data set. However, the choice of validation index had an even greater impact (up to 15 000%). This indicates that studies using opportunistic data for SDM fitting need to pay attention to the effects of presence/absence data imbalance and the choice of validation index to fully evaluate uncertainty. © 2022 Elsevier B.V. All rights reserved.The study received financial support from France Filière Pêche (project DynRose) and the European Union’s Horizon 2020 research and innovation programme under Grant Agreement No 773713 (PANDORA).Pagellus bogaraveo; Species distribution models; Ensemble modelling; Heterogeneous data set; Presence–absence imbalancePeer reviewe

Reduction of cardiac imaging tests during the COVID-19 pandemic: The case of Italy. Findings from the IAEA Non-invasive Cardiology Protocol Survey on COVID-19 (INCAPS COVID)

Background: In early 2020, COVID-19 massively hit Italy, earlier and harder than any other European country. This caused a series of strict containment measures, aimed at blocking the spread of the pandemic. Healthcare delivery was also affected when resources were diverted towards care of COVID-19 patients, including intensive care wards. Aim of the study: The aim is assessing the impact of COVID-19 on cardiac imaging in Italy, compare to the Rest of Europe (RoE) and the World (RoW). Methods: A global survey was conducted in May–June 2020 worldwide, through a questionnaire distributed online. The survey covered three periods: March and April 2020, and March 2019. Data from 52 Italian centres, a subset of the 909 participating centres from 108 countries, were analyzed. Results: In Italy, volumes decreased by 67% in March 2020, compared to March 2019, as opposed to a significantly lower decrease (p &lt; 0.001) in RoE and RoW (41% and 40%, respectively). A further decrease from March 2020 to April 2020 summed up to 76% for the North, 77% for the Centre and 86% for the South. When compared to the RoE and RoW, this further decrease from March 2020 to April 2020 in Italy was significantly less (p = 0.005), most likely reflecting the earlier effects of the containment measures in Italy, taken earlier than anywhere else in the West. Conclusions: The COVID-19 pandemic massively hit Italy and caused a disruption of healthcare services, including cardiac imaging studies. This raises concern about the medium- and long-term consequences for the high number of patients who were denied timely diagnoses and the subsequent lifesaving therapies and procedures

International Impact of COVID-19 on the Diagnosis of Heart Disease

Background: The coronavirus disease 2019 (COVID-19) pandemic has adversely affected diagnosis and treatment of noncommunicable diseases. Its effects on delivery of diagnostic care for cardiovascular disease, which remains the leading cause of death worldwide, have not been quantified. Objectives: The study sought to assess COVID-19's impact on global cardiovascular diagnostic procedural volumes and safety practices. Methods: The International Atomic Energy Agency conducted a worldwide survey assessing alterations in cardiovascular procedure volumes and safety practices resulting from COVID-19. Noninvasive and invasive cardiac testing volumes were obtained from participating sites for March and April 2020 and compared with those from March 2019. Availability of personal protective equipment and pandemic-related testing practice changes were ascertained. Results: Surveys were submitted from 909 inpatient and outpatient centers performing cardiac diagnostic procedures, in 108 countries. Procedure volumes decreased 42% from March 2019 to March 2020, and 64% from March 2019 to April 2020. Transthoracic echocardiography decreased by 59%, transesophageal echocardiography 76%, and stress tests 78%, which varied between stress modalities. Coronary angiography (invasive or computed tomography) decreased 55% (p &lt; 0.001 for each procedure). In multivariable regression, significantly greater reduction in procedures occurred for centers in countries with lower gross domestic product. Location in a low-income and lower–middle-income country was associated with an additional 22% reduction in cardiac procedures and less availability of personal protective equipment and telehealth. Conclusions: COVID-19 was associated with a significant and abrupt reduction in cardiovascular diagnostic testing across the globe, especially affecting the world's economically challenged. Further study of cardiovascular outcomes and COVID-19–related changes in care delivery is warranted

Impact of COVID-19 on Diagnostic Cardiac Procedural Volume in Oceania: The IAEA Non-Invasive Cardiology Protocol Survey on COVID-19 (INCAPS COVID)

Objectives: The INCAPS COVID Oceania study aimed to assess the impact caused by the COVID-19 pandemic on cardiac procedure volume provided in the Oceania region. Methods: A retrospective survey was performed comparing procedure volumes within March 2019 (pre-COVID-19) with April 2020 (during first wave of COVID-19 pandemic). Sixty-three (63) health care facilities within Oceania that perform cardiac diagnostic procedures were surveyed, including a mixture of metropolitan and regional, hospital and outpatient, public and private sites, and 846 facilities outside of Oceania. The percentage change in procedure volume was measured between March 2019 and April 2020, compared by test type and by facility. Results: In Oceania, the total cardiac diagnostic procedure volume was reduced by 52.2% from March 2019 to April 2020, compared to a reduction of 75.9% seen in the rest of the world (p&lt;0.001). Within Oceania sites, this reduction varied significantly between procedure types, but not between types of health care facility. All procedure types (other than stress cardiac magnetic resonance [CMR] and positron emission tomography [PET]) saw significant reductions in volume over this time period (p&lt;0.001). In Oceania, transthoracic echocardiography (TTE) decreased by 51.6%, transoesophageal echocardiography (TOE) by 74.0%, and stress tests by 65% overall, which was more pronounced for stress electrocardiograph (ECG) (81.8%) and stress echocardiography (76.7%) compared to stress single-photon emission computerised tomography (SPECT) (44.3%). Invasive coronary angiography decreased by 36.7% in Oceania. Conclusion: A significant reduction in cardiac diagnostic procedure volume was seen across all facility types in Oceania and was likely a function of recommendations from cardiac societies and directives from government to minimise spread of COVID-19 amongst patients and staff. Longer term evaluation is important to assess for negative patient outcomes which may relate to deferral of usual models of care within cardiology