scholarly journals Invasion dynamics of the European bumblebee Bombus terrestris in the southern part of South America

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Francisco E. Fontúrbel ◽  
Maureen M. Murúa ◽  
Lorena Vieli

AbstractInvasive species are one of the main biodiversity loss drivers. Some species can establish and thrive in novel habitats, impacting local communities, as is the case of managed pollinators. In this regard, an invasive species' expansion process over time is critical for its control and management. A good example is the European bumblebee Bombus terrestris, which has rapidly invaded the southern part of South America after being repeatedly introduced in Chile for crop pollination since 1997. We assessed the temporal dynamics of B. terrestris invasion in Argentina and Chile by compiling 562 occurrence points from 2000 to 2019. We used two estimators (minimum convex polygon and 95% fixed kernel) to estimate the increase of the invaded area over time. We found that the area invaded by B. terrestris in the southern part of South America presents a linear increase over time, which was consistent for both estimators. In this scenario, species traits, environmental characteristics, and introduction dynamics facilitate a rapid invasion process that will continue to expand, reaching other South American countries in the near future. As this bumblebee is a super-generalist, it probably will expand across South America, as climate niche modelling predicts, if no actions were taken.

2017 ◽  
pp. 1-5 ◽  
Author(s):  
Javier Alejandro Rendoll-Carcamo ◽  
Tamara Andrea Contador ◽  
Lorena Saavedra ◽  
José Montalva

As the volume of global trade expands, so does the risk of alien species reaching new regions.  Bombus (Bombus) terrestris (Linnaeus) (Hymenoptera: Apidae) is a bumble bee traded internationally for crop pollination and is now considered an invasive species in New Zealand, Japan, and throughout South America.  We newly document its presence on Navarino Island, Cape Horn, Biosphere Reserve, Chile (55°S), the southernmost locality reached by this species to date.


2020 ◽  
Vol 7 (Supplement_1) ◽  
pp. S597-S597
Author(s):  
Jasmine R Marcelin ◽  
Rohan Khazanchi ◽  
Elizabeth Lyden ◽  
Kelly Cawcutt ◽  
Ravina Kullar ◽  
...  

Abstract Background Over the last decade, there have been sustained efforts to diversify the healthcare workforce. In 2016, the IDWeek Program Committee was charged to ensure gender equity in speaker sessions. Whether this intervention also resulted in more opportunities for underrepresented speakers has not been determined. Methods This project was supported by IDSA, who provided demographic information on IDWeek speakers (excluding poster sessions) from 2013-2019. Data were summarized using descriptive statistics, and chi-square analysis evaluated changes over time. Each speaker slot was considered an independent event. Data was combined for 2013-2016 (≤2016) and 2017-2019 (>2016). IDSA membership demographics were available from 2014 for gender, race/ethnicity, from 2016 for age, and from 2018 for professional degree. Results A total of 3640 speaker slots were filled by 2504 individuals from 2013-2019. A larger proportion of speaker slots were filled by women >2016 (51%) vs ≤ 2016 (43%), with a linear increase from 38.6% in 2013 to 52.1% in 2019 (p< 0.001). Averaged across 2013-2019, IDSA membership was 67.5% White, 20.6% Asian, 7.7% Latinx, 3.9% Black, and 0.4% Other. IDWeek Speakers during that timeframe were 77.7% White, 13.9% Asian, 4.7% Latinx, 2.7% Black, and 1.0% Other; a larger proportion of slots were filled by Asian speakers >2016 (16.3%) vs ≤ 2016 (12.8%) (p=0.005). The proportion of pharmacist speakers increased over time; 5.1% of speakers in 2019 reflected IDSA pharmacist membership (5.4%). The proportion of individuals invited to speak more than once differed by age (19% in < 40yo, 28% 40-49yo, 32% 50-59yo, and 22% >60yo; p< 0.001), and professional degree (28% physicians, 18% pharmacists, 9% other doctorates, and 7% non-doctorate speakers; p< 0.001). Figure 1: Trends in Gender Distribution of IDWeek Speakers and IDSA Members, 2013-2019 Figure 2: Trends in Race/Ethnicity Distribution of IDWeek Speakers and IDSA Members, 2013-2019 Conclusion Intentional consideration of gender equity by the Program Committee significantly improved equitable gender representation of invited speakers at IDWeek. This effort has not resulted in increased diversity of invited speakers from groups underrepresented in IDSA membership. To ensure that invited speakers represent the membership of IDSA/IDWeek partner organizations and more importantly, the communities we serve, we call for continued application of the principles of Inclusion, Diversity, Access, and Equity at IDWeek. Disclosures All Authors: No reported disclosures


Author(s):  
Thomas L Rodebaugh ◽  
Madelyn R Frumkin ◽  
Angela M Reiersen ◽  
Eric J Lenze ◽  
Michael S Avidan ◽  
...  

Abstract Background The symptoms of COVID-19 appear to be heterogenous, and the typical course of these symptoms is unknown. Our objectives were to characterize the common trajectories of COVID-19 symptoms and assess how symptom course predicts other symptom changes as well as clinical deterioration. Methods 162 participants with acute COVID-19 responded to surveys up to 31 times for up to 17 days. Several statistical methods were used to characterize the temporal dynamics of these symptoms. Because nine participants showed clinical deterioration, we explored whether these participants showed any differences in symptom profiles. Results Trajectories varied greatly between individuals, with many having persistently severe symptoms or developing new symptoms several days after being diagnosed. A typical trajectory was for a symptom to improve at a decremental rate, with most symptoms still persisting to some degree at the end of the reporting period. The pattern of symptoms over time suggested a fluctuating course for many patients. Participants who showed clinical deterioration were more likely to present with higher reports of severity of cough and diarrhea. Conclusion The course of symptoms during the initial weeks of COVID-19 is highly heterogeneous and is neither predictable nor easily characterized using typical survey methods. This has implications for clinical care and early-treatment clinical trials. Additional research is needed to determine whether the decelerating improvement pattern seen in our data is related to the phenomenon of patients reporting long-term symptoms, and whether higher symptoms of diarrhea in early illness presages deterioration.


Author(s):  
Mari Huhtala ◽  
Muel Kaptein ◽  
Joona Muotka ◽  
Taru Feldt

AbstractThe aim of this longitudinal study was to investigate the temporal dynamics of ethical organisational culture and how it associates with well-being at work when potential changes in ethical culture are measured over an extended period of 6 years. We used a person-centred study design, which allowed us to detect both typical and atypical patterns of ethical culture stability as well as change among a sample of leaders. Based on latent profile analysis and hierarchical linear modelling we found longitudinal, concurrent relations and cumulative gain and loss cycles between different ethical culture patterns and leaders’ well-being. Leaders in the strongest ethical culture pattern experienced the highest level of work engagement and a decreasing level of ethical dilemmas and stress. Leaders who gave the lowest ratings on ethical culture which also decreased over time reported the highest level of ethical dilemmas, stress, and burnout. They also showed a continuous increase in these negative outcomes over time. Thus, ethical culture has significant cumulative effects on well-being, and these longitudinal effects can be both negative and positive, depending on the experienced strength of the culture’s ethicality.


2020 ◽  
Vol 7 (Supplement_1) ◽  
pp. S325-S326
Author(s):  
Lacy Simons ◽  
Ramon Lorenzo-Redondo ◽  
Hannah Nam ◽  
Scott C Roberts ◽  
Michael G Ison ◽  
...  

Abstract Background The rapid spread of SARS-CoV-2, the causative agent of Coronavirus disease 2019 (COVID-19), has been accompanied by the emergence of viral mutations, some of which may have distinct virological and clinical consequences. While whole genome sequencing efforts have worked to map this viral diversity at the population level, little is known about how SARS-CoV-2 may diversify within a host over time. This is particularly important for understanding the emergence of viral resistance to therapeutic interventions and immune pressure. The goal of this study was to assess the change in viral load and viral genome sequence within patients over time and determine if these changes correlate with clinical and/or demographic parameters. Methods Hospitalized patients admitted to Northwestern Memorial Hospital with a positive SARS-CoV-2 test were enrolled in a longitudinal study for the serial collection of nasopharyngeal specimens. Swabs were administered to patients by hospital staff every 4 ± 1 days for up to 32 days or until the patients were discharged. RNA was extracted from each specimen and viral loads were calculated by quantitative reverse transcriptase PCR (qRT-PCR). Specimens with qRT-PCR cycle threshold values less than or equal to 30 were subject to whole viral genome sequencing by reverse transcription, multiplex PCR, and deep sequencing. Variant populations sizes were estimated and subject to phylogenetic analysis relative to publicly available SARS-CoV-2 sequences. Sequence and viral load data were subsequently correlated to available demographic and clinical data. Results 60 patients were enrolled from March 26th to June 20th, 2020. We observed an overall decrease in nasopharyngeal viral load over time across all patients. However, the temporal dynamics of viral load differed on a patient-by-patient basis. Several mutations were also observed to have emerged within patients over time. Distribution of SARS-CoV-2 viral loads in serially collected nasopharyngeal swabs in hospitalized adults as determined by qRT-PCR. Samples were collected every 4 ± 1 days (T#1–8) and viral load is displayed by log(copy number). Conclusion These data indicate that SARS-CoV-2 viral loads in the nasopharynx decrease over time and that the virus can accumulate mutations during replication within individual patients. Future studies will examine if some of these mutations may provide fitness advantages in the presence of therapeutic and/or immune selective pressures. Disclosures Michael G. Ison, MD MS, AlloVir (Consultant)


2021 ◽  
Author(s):  
Rob Cowie ◽  
Romi L. Burks ◽  
Amy E. Miller ◽  
Alexandria L. Hill

Abstract P. maculata is a freshwater snail native to a wide geographical area in South America from the Rio de la Plata in Argentina and Uruguay to the Amazon in Brazil. It is commonly confused with any number of similar large apple snails, including the well-known invasive golden apple snail Pomacea canaliculata (listed among '100 of the world's worst invasive species'). Both species have been introduced to South-East and East Asia, although for many years they were not distinguished and the Asian introductions were widely identified as "golden apple snails" and the name P. canaliculata was applied to them. Due to the confusion in species identification, the history of introduction of P. maculata remains somewhat uncertain as does its invasiveness and pest potential. Much of the literature is confounded, for example, the snails illustrated by Cowie (2002) as P. canaliculata are in fact P. maculata. The majority of invasive populations in Asia appear to be P. canaliculata, often not mixed with P. maculata (Hayes et al., 2008; Tran et al., 2008) and the pest potential of P. canaliculata in such cases is clear. However, much less has been written about the invasiveness and pest potential of 'P. maculata'.


2015 ◽  
Vol 39 (4) ◽  
pp. 603-610
Author(s):  
Vinícius Londe ◽  
Hildeberto Caldas de Sousa ◽  
Alessandra Rodrigues Kozovits

ABSTRACTAs important as the establishment of projects of ecological restoration is its assessment post-implementation to know whether the area is becoming self-sustainable or need to be redirected. In this way, this study aimed to know the current situation of a 5-year-old rehabilitated riparian forest,inserted in an anthropogenic impacted region,at the das Velhas River, Minas Gerais State, studying the canopy openness and recruitment of seedlings as plant indicators. 15 plots were allocated in the forest, where hemispherical photographs were taken to analyze the canopy openness and evaluate all seedlings from 0.30 m to 1.30 m height.Canopy openness ranged from 23.7% to 38.8% between seasons and only 192 seedlings were found,from 13 species, five of them exotic and aggressive. Although canopy openness was low, it seems that lateral penetration of light has been favoring the development and dominancy of plants from invasive species, whereas few native ones have been recruited. The exotic/invasive plants may compromise the success of restoration mainly by competition with native planted species. The outcomes evidenced an unsustainability of the riparian forest and the requirement of some management actions to control exotic and invasive plants and ensure the preservation of the area and its ecological roles over time.


2021 ◽  
Vol 11 ◽  
Author(s):  
Janneke Schreuder ◽  
Francisca C. Velkers ◽  
Alex Bossers ◽  
Ruth J. Bouwstra ◽  
Willem F. de Boer ◽  
...  

Associations between animal health and performance, and the host’s microbiota have been recently established. In poultry, changes in the intestinal microbiota have been linked to housing conditions and host development, but how the intestinal microbiota respond to environmental changes under farm conditions is less well understood. To gain insight into the microbial responses following a change in the host’s immediate environment, we monitored four indoor flocks of adult laying chickens three times over 16 weeks, during which two flocks were given access to an outdoor range, and two were kept indoors. To assess changes in the chickens’ microbiota over time, we collected cloacal swabs of 10 hens per flock and performed 16S rRNA gene amplicon sequencing. The poultry house (i.e., the stable in which flocks were housed) and sampling time explained 9.2 and 4.4% of the variation in the microbial community composition of the flocks, respectively. Remarkably, access to an outdoor range had no detectable effect on microbial community composition, the variability of microbiota among chickens of the same flock, or microbiota richness, but the microbiota of outdoor flocks became more even over time. Fluctuations in the composition of the microbiota over time within each poultry house were mainly driven by turnover in rare, rather than dominant, taxa and were unique for each flock. We identified 16 amplicon sequence variants that were differentially abundant over time between indoor and outdoor housed chickens, however none were consistently higher or lower across all chickens of one housing type over time. Our study shows that cloacal microbiota community composition in adult layers is stable following a sudden change in environment, and that temporal fluctuations are unique to each flock. By exploring microbiota of adult poultry flocks within commercial settings, our study sheds light on how the chickens’ immediate environment affects the microbiota composition.


2021 ◽  
Author(s):  
◽  
Simon Lovatt

<p>Invasive species are one of the biggest threats to development and well-being in the Pacific. They have wide-ranging impacts on economies, the environment, and societies; in addition to causing USD $1.4 trillion of losses each year. Invasive species are also the primary cause of biodiversity loss on islands which could significantly affect the ecosystem services which Pacific Islanders depend on. Every year New Zealand spends NZD $500 million on biosecurity, and Australia has spent AUD $175 million on a single eradication project. In comparison, in the Pacific there are only six people working fulltime on invasive species issues at a regional level and there is limited funding available. This thesis assesses the role of four New Zealand agencies that assist with invasive species management in the Pacific: the International Development Group of the Ministry of Foreign Affairs, the Biosecurity New Zealand division of the Ministry of Agriculture and Forestry, the Department of Conservation, and Landcare Research. Together these agencies provide funding, build capacity, offer technical advice, and occasionally implement projects. While there are important gains to New Zealand in assisting the Pacific with invasive species management, such as a reduced biosecurity threat and learning opportunities for staff, the desire to help the region for its own sake is a major driver. Suggestions for future improvement include having more information on the economic impacts of invasive species in the Pacific, increased coordination between donors, and including invasive species measures in regional trade agreements. It is hoped that New Zealand will continue to play its critical leadership role in invasive species management in the region.</p>


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