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1.
PLoS One ; 19(5): e0303335, 2024.
Article in English | MEDLINE | ID: mdl-38776282

ABSTRACT

In a time of increasing threats to bumble bees (Hymenoptera: Apidae: Bombus), it is important to understand their ecology and distribution. As experts are limited in resources to conduct field surveys, there is potential for community scientists to help. The Bumble Bee Watch (BBW) community science program involves volunteers taking photos of bumble bees in Canada and the USA and submitting them, along with geographic and optional plant information, to a website or through an app. Taxon experts then verify the bee species identification. The Bumble Bees of North America database (BBNA) stores data (no photographs) collected and identified by more traditional scientific methods over the same range. Here we compared BBW data to BBNA data over all years and just 2010-2020 to understand the scientific contribution of community scientists to the state of the knowledge about native bumble bees. We found that BBW had similar geographic and species coverage as BBNA. It had records from all 63 provinces, states, and territories where bumble bees occur (including four more than BBNA in 2010-2020), and represented 41 of the 48 species in BBNA (with ten more species than BBNA in 2010-2020). While BBW contributed only 8.50% of records overall, it contributed 25.06% of all records over 2010-2020. BBW confirmed the persistence of species and identified new locations of species, both inside and outside of the previously known extent of occurrences. BBW also contributed a wealth of ecological information, such as unique plant genera and species data for almost all the bee species. Thus, while BBW had fewer bee records than the BBNA database overall, it helped to fill in data gaps and provided novel information, complementing the traditional methods. This community science program is valuable in helping to inform conservation management for bumble bee species.


Subject(s)
Pollination , Animals , Bees/physiology , United States , Canada , Databases, Factual
2.
Proc Natl Acad Sci U S A ; 120(5): e2211223120, 2023 Jan 31.
Article in English | MEDLINE | ID: mdl-36689649

ABSTRACT

The acute decline in global biodiversity includes not only the loss of rare species, but also the rapid collapse of common species across many different taxa. The loss of pollinating insects is of particular concern because of the ecological and economic values these species provide. The western bumble bee (Bombus occidentalis) was once common in western North America, but this species has become increasingly rare through much of its range. To understand potential mechanisms driving these declines, we used Bayesian occupancy models to investigate the effects of climate and land cover from 1998 to 2020, pesticide use from 2008 to 2014, and projected expected occupancy under three future scenarios. Using 14,457 surveys across 2.8 million km2 in the western United States, we found strong negative relationships between increasing temperature and drought on occupancy and identified neonicotinoids as the pesticides of greatest negative influence across our study region. The mean predicted occupancy declined by 57% from 1998 to 2020, ranging from 15 to 83% declines across 16 ecoregions. Even under the most optimistic scenario, we found continued declines in nearly half of the ecoregions by the 2050s and mean declines of 93% under the most severe scenario across all ecoregions. This assessment underscores the tenuous future of B. occidentalis and demonstrates the scale of stressors likely contributing to rapid loss of related pollinator species throughout the globe. Scaled-up, international species-monitoring schemes and improved integration of data from formal surveys and community science will substantively improve the understanding of stressors and bumble bee population trends.


Subject(s)
Pesticides , Bees , Animals , Bayes Theorem , Biodiversity , Insecta , Climate
3.
Environ Entomol ; 50(5): 1095-1104, 2021 10 12.
Article in English | MEDLINE | ID: mdl-34145877

ABSTRACT

In June of 2013 an application of dinotefuran on an ornamental planting of European linden trees (Tilia cordata Mill. [Malvales: Malvalceae]) in a shopping mall parking lot in Wilsonville, Oregon provoked the largest documented pesticide kill of bumble bees in North America. Based on geographic information systems and population genetic analysis, we estimate that between 45,830 and 107,470 bumble bees originating from between 289 and 596 colonies were killed during this event. Dinotefuran is a neonicotinoid that is highly effective in exterminating and/or harming target pest insects and non-target beneficial insects. Analysis to detect the concentration of pesticides in flowers that received foliar application revealed that the minimum reported dinotefuran concentration of a sampled T. cordata flower was 7.4 ppm, or in excess of 737% above the LC50 of the beneficial pollinator, the honey bee (Apis mellifera Linnaeus, 1758 [Hymenoptera: Apidae]). Furthermore, sampled Vosnesensky bumble bees (Bombus vosnesenskii Radoskowski, 1862 [Hymenoptera: Apidae]) were found to have an average dinotefuran concentration of 0.92 ppm at the time of death, which exceeds the maximum LC50 of A. mellifera (0.884 ppm). Our study underscores the lethal impact of the neonicotinoid pesticide dinotefuran on pollinating insect populations in a suburban environment. To our knowledge, the documentation and impact of pesticide kills on wild populations of beneficial insects has not been widely reported in the scientific literature. It is likely that the vast majority of mass pesticide kills of beneficial insects across other environments go unnoticed and unreported.


Subject(s)
Hymenoptera , Pesticides , Animals , Bees , Flowers , Neonicotinoids/toxicity , Oregon
4.
Sci Rep ; 11(1): 7580, 2021 04 07.
Article in English | MEDLINE | ID: mdl-33828196

ABSTRACT

Pollinators are undergoing a global decline. Although vital to pollinator conservation and ecological research, species-level identification is expensive, time consuming, and requires specialized taxonomic training. However, deep learning and computer vision are providing ways to open this methodological bottleneck through automated identification from images. Focusing on bumble bees, we compare four convolutional neural network classification models to evaluate prediction speed, accuracy, and the potential of this technology for automated bee identification. We gathered over 89,000 images of bumble bees, representing 36 species in North America, to train the ResNet, Wide ResNet, InceptionV3, and MnasNet models. Among these models, InceptionV3 presented a good balance of accuracy (91.6%) and average speed (3.34 ms). Species-level error rates were generally smaller for species represented by more training images. However, error rates also depended on the level of morphological variability among individuals within a species and similarity to other species. Continued development of this technology for automatic species identification and monitoring has the potential to be transformative for the fields of ecology and conservation. To this end, we present BeeMachine, a web application that allows anyone to use our classification model to identify bumble bees in their own images.


Subject(s)
Artificial Intelligence , Bees/anatomy & histology , Bees/classification , Deep Learning , Animals , Conservation of Natural Resources , Databases, Factual , Ecosystem , Image Processing, Computer-Assisted , Neural Networks, Computer , North America , Pigmentation , Pollination , Species Specificity
5.
PeerJ ; 8: e9412, 2020.
Article in English | MEDLINE | ID: mdl-32655993

ABSTRACT

Community science programs provide an opportunity to gather scientific data to inform conservation policy and management. This study examines the accuracy of community science identifications submitted to the North American Bumble Bee Watch program on a per species level and as compared to each species' conservation status, as well as users (members of the public) and experts (those with expertise in the field of bumble bee biology) perceived ease of species identification. Photos of bumble bees (Hymenoptera: Apidae: Bombus) are submitted to the program by users and verified (species name corrected or assigned as necessary) by an expert. Over 22,000 records from over 4,900 users were used in the analyses. Accuracy was measured in two ways: percent agreement (percent of all records submitted correctly by users) and veracity (percent of all verified records submitted correctly by the users). Users generally perceived it harder to identify species than experts. User perceptions were not significantly different from the observed percent agreement or veracity, while expert perceptions were significantly different (overly optimistic) from the observed percent agreement but not the veracity. We compared user submitted names to final expert verified names and found that, for all species combined, the average percent agreement was 53.20% while the average veracity was 55.86%. There was a wide range in percent agreement values per species, although sample size and the role of chance did affect some species agreements. As the conservation status of species increased to higher levels of extinction risk, species were increasingly more likely to have a lower percent agreement but higher levels of veracity than species of least concern. For each species name submitted, the number of different species verified by experts varied from 1 to 32. Future research may investigate which factors relate to success in user identification through community science. These findings could play a role in informing the design of community science programs in the future, including for use in long-term and national-level monitoring of wild pollinators.

6.
Epilepsy Behav ; 111: 107196, 2020 10.
Article in English | MEDLINE | ID: mdl-32554230

ABSTRACT

OBJECTIVE: The objective of the study was to assess the long-term outcomes of epilepsy surgery between 1995 and 2015 in South Wales, UK, linking case note review, postal questionnaire, and routinely collected healthcare data. METHOD: We identified patients from a departmental database and collected outcome data from patient case notes, a postal questionnaire, and the QOLIE-31-P and linked with Welsh routinely collected data in the Secure Anonymised Information Linkage (SAIL) databank. RESULTS: Fifty-seven patients were included. Median age at surgery was 34 years (11-70), median: 24 years (2-56) after onset of habitual seizures. Median follow-up was 7 years (2-19). Twenty-eight (49%) patients were free from disabling seizures (Engel Class 1), 9 (16%) experienced rare disabling seizures (Class 2), 13 (23%) had worthwhile improvements (Class 3), and 7 (12%) had no improvement (Class 4). There was a 30% mean reduction in total antiepileptic drug (AED) load at five years postsurgery. Thirty-eight (66.7%) patients experienced tonic-clonic seizures presurgery verses 8 (14%) at last review. Seizure-free patients self-reported a greater overall quality of life (QOL; QOLIE-31-P) when compared with those not achieving seizure freedom. Seizure-free individuals scored a mean of 67.6/100 (100 is best), whereas those with continuing seizures scored 46.0/100 (p < 0.006). There was a significant decrease in the median rate of hospital admissions for any cause after epilepsy surgery (9.8 days per 1000 patient days before surgery compared with 3.9 after p < 0.005). SIGNIFICANCE: Epilepsy surgery was associated with significant improvements in seizures, a reduced AED load, and an improved QOL that closely correlated with seizure outcomes and reduced hospital admission rates following surgery. Despite this, there was a long delay from onset of habitual seizures to surgery. The importance of long-term follow-up is emphasized in terms of evolving medical needs and health and social care outcomes.


Subject(s)
Data Analysis , Epilepsy/surgery , Patient Acceptance of Health Care , Patient Reported Outcome Measures , Surveys and Questionnaires , Adolescent , Adult , Aged , Child , Cohort Studies , Epilepsy/epidemiology , Female , Humans , Male , Middle Aged , Retrospective Studies , Time Factors , Treatment Outcome , Wales/epidemiology , Young Adult
9.
Int J Occup Environ Health ; 16(3): 279-90, 2010.
Article in English | MEDLINE | ID: mdl-20662420

ABSTRACT

Several studies were designed and conducted to evaluate amphibole asbestos exposures in homes containing Zonolite (expanded vermiculite) attic insulation (ZAI). A range of tasks selected for evaluation included cleaning, working around, moving, and removal of ZAI in attics and living spaces. The fieldwork for these studies was conducted at two homes in Spokane, WA and one home in Silver Spring, MD. Personal and area air samples were collected and analyzed as part of the exposure studies. Surface dust samples and bulk samples were also collected and analyzed. The results demonstrated that airborne concentrations of amphibole asbestos were not elevated if the material is undisturbed. The results also demonstrated that cleaning, remodeling, and other activities did produce significant concentrations of airborne amphibole asbestos when the ZAI was disturbed.


Subject(s)
Air Pollutants, Occupational/analysis , Aluminum Silicates/analysis , Asbestos, Amphibole/analysis , Occupational Exposure/analysis , Housing , Humans , Workplace
10.
Br J Neurosurg ; 24(4): 401-4, 2010 Aug.
Article in English | MEDLINE | ID: mdl-20632882

ABSTRACT

AIM: Investigation of the influence of light on bilirubin degradation over time in cerebrospinal fluid (CSF) specimens from patients with computed tomography (CT) positive subarachnoid haemorrhage (SAH). METHODS: Twenty-nine CSF samples were analysed from 23 patients with CT-positive SAH. Samples were divided into two cohorts - one half being stored in the dark, the other in normal room light conditions. Samples were assayed by spectrophotometry 0, 1, 2, 6, 19, 24 and 48 h post-storage. Net bilirubin absorbance (NBA) was measured in absorbance units (AU) by determining the optical density at 476 nm. RESULTS: In 27 of 28 (96%) samples stored in light conditions and 21 of 29 (72%) samples stored in dark, a decline in the amount of bilirubin detected in CSF over time was observed. The rate of bilirubin degradation over 24 h for CSF samples stored in the light ranged from 0.0001 to 0.0048 AU/h (mean 0.0020 AU/h), and was significantly greater (p < 0.01) than the rate of degradation in the dark, which ranged from 0 to 0.0024 AU/h (mean 0.0005 AU/h). CONCLUSION: CSF bilirubin samples are susceptible to the same photodegradation as shown in serum bilirubin samples. The rate of degradation is not predictable or consistent. This photodegradation may potentially produce false-negative results in the diagnosis of SAH. If spectrophotometry cannot be carried out immediately, all such CSF samples should at least be centrifuged immediately, the supernatant protected from light as soon as possible and the collection and analysis times provided in the report.


Subject(s)
Bilirubin/cerebrospinal fluid , Light , Spectrophotometry/methods , Subarachnoid Hemorrhage/cerebrospinal fluid , Bilirubin/metabolism , Female , Humans , Male , Prospective Studies , Specimen Handling , Subarachnoid Hemorrhage/diagnosis , Subarachnoid Hemorrhage/diagnostic imaging , Time Factors , Tomography, X-Ray Computed
11.
Acta Neurochir (Wien) ; 152(5): 803-15, 2010 May.
Article in English | MEDLINE | ID: mdl-20054699

ABSTRACT

CASE REPORT: We report two cases of operative intervention that was beneficial in the treatment of delayed symptomatic radionecrotic masses that had developed following stereotactic radiosurgery (SRS) using the gamma knife (GK) for the treatment of cerebral arteriovenous malformations (AVM). DISCUSSION: Case 1 involved a small craniotomy for decompression of a large cerebral multiloculated cyst, which had become symptomatic 84 months following gamma knife treatment for a left frontal lobe AVM. Case 2 involved surgical excision of an occipital radionecrotic mass 72 months following GK treatment for an occipital AVM. This patient had suffered from longstanding symptomatic cerebral oedema, which on occasions had become life threatening. Case 2 is also the first report of a radionecrotic mass occurring post-SRS for an AVM, which conversely appeared to demonstrate increased uptake on single photon emission computed tomography (SPECT) scan. The first literature review of such delayed symptomatic radionecrotic lesions is presented. There appears to be a late onset of symptoms (average 55 months, range 12-111 months) associated with such radionecrosis. Drainage of such cysts or excision of the mass lesion appears to be consistently beneficial to the patients and appears to be uncomplicated. CONCLUSION: We recommend early surgical intervention for such delayed symptomatic radionecrotic masses that do not resolve following non-operative management. We also recommend caution in interpretation of SPECT scan results when attempting to differentiate radionecrosis from neoplasia.


Subject(s)
Brain/surgery , Intracranial Arteriovenous Malformations/surgery , Necrosis/surgery , Radiation Injuries/surgery , Radiosurgery/adverse effects , Adult , Brain/diagnostic imaging , Brain/pathology , Central Nervous System Cysts/etiology , Central Nervous System Cysts/pathology , Central Nervous System Cysts/surgery , Craniotomy/methods , Decompression, Surgical/methods , Humans , Intracranial Arteriovenous Malformations/diagnostic imaging , Intracranial Arteriovenous Malformations/pathology , Magnetic Resonance Imaging , Male , Necrosis/pathology , Necrosis/physiopathology , Neurosurgical Procedures/methods , Postoperative Complications/pathology , Postoperative Complications/physiopathology , Postoperative Complications/surgery , Radiation Injuries/pathology , Radiation Injuries/physiopathology , Radiosurgery/methods , Reoperation , Tomography, Emission-Computed, Single-Photon , Tomography, X-Ray Computed , Treatment Outcome
12.
J Occup Environ Hyg ; 2(8): 375-82, 2005 Aug.
Article in English | MEDLINE | ID: mdl-16080259

ABSTRACT

The work reported here evaluates the effectiveness of various rates of dilution ventilation in controlling welder exposures to manganese in shielded metal arc welding (SMAW) fume when working in enclosed or restricted spaces. Personal and area monitoring using total and respirable sampling techniques, along with multiple analytical techniques, was conducted during the welding operations. With 2000 cubic feet per minute (CFM) (56.63 m3/min) dilution ventilation, personal breathing zone concentrations for the welder using 1/8 inches (3.18 mm) E6010 and E7018 mild steel electrodes were within 75% of the existing threshold limit value (TLV of 0.2 mg/m3 for total manganese and were five times greater than the 2001-2003 proposed respirable manganese TLV of 0.03 mg/m3. Manganese concentrations using high manganese content electrodes were five times greater than those for E6010 and E7018 electrodes. Area samples upstream and downstream of the welder using E6010 and E7018 electrodes exceeded 0.2 mg/m3 manganese. Concentrations inside and outside the welding helmet do not indicate diversion of welding fume by the welding helmet from the welder's breathing zone. There was close agreement between respirable manganese and total manganese fume concentrations. Total fume concentrations measured by gravimetric analysis of matched-weight, mixed cellulose ester filters were comparable to those measured via preweighed PVC filter media. This study indicates that 2000 CFM general dilution ventilation per 29 CFR 1910.252 (c)(2) may not be a sufficient means of controlling respirable manganese exposures for either welders or their helpers in restricted or enclosed spaces. In the absence of site-specific monitoring data indicating otherwise, it is prudent to employ respiratory protection or source capture ventilation for SMAW with E6010, E7018, and high manganese content electrodes rather than depending solely on 2000 CFM general dilution ventilation in enclosed spaces.


Subject(s)
Confined Spaces , Manganese/analysis , Occupational Exposure/analysis , Welding/methods , Environmental Monitoring/methods , Head Protective Devices , Humans , Inhalation Exposure/analysis , Inhalation Exposure/prevention & control , Occupational Exposure/prevention & control , Occupational Exposure/standards , Threshold Limit Values , Ventilation/methods , Ventilation/standards
14.
Appl Occup Environ Hyg ; 17(1): 55-62, 2002 Jan.
Article in English | MEDLINE | ID: mdl-11800407

ABSTRACT

Work practice studies were conducted involving the removal of asbestos-containing sheet gaskets from steam flanges. These studies were performed to determine potential exposure levels to individuals who have worked with these types of materials in the past and may still work with these products today. The work practices were conducted inside an exposure characterization laboratory (ECL) and were performed by scraping and wire brushing, chrysotile-containing (65% to 85%) sheet gaskets from a number of used steam flanges. Airborne asbestos levels were measured by phase contrast microscopy (PCM) and transmission electron microscopy (TEM) for the personnel and area air samples collected during the study. These workplace simulations showed substantial asbestos fiber release using scraping, hand wire brushing, and power wire brushing techniques during the gasket removal process. The range of concentration was 2.1 to 31.0 fibers/cc greater than 5 micrometers when measured by PCM. These results contrasted with the few reported results in the published literature where lower airborne asbestos levels were reported. In these studies the airborne asbestos fiber levels measured in many of the samples exceeded all current and historical Occupational Safety and Health Administration (OSHA) excursion limits (15-30 minutes) and some previous permissible exposure limits (PEL) based on eight-hour time-weighted average (TWA) standards. Also, individuals who performed this type of work in the past may have had exposures higher than previously suspected. The results demonstrated that employees who remove dry asbestos-containing gaskets with no localized ventilation should wear a full face supplied air respirator with a HEPA escape canister and the work area should be designated a regulated area.


Subject(s)
Air Pollution, Indoor/analysis , Asbestos/analysis , Occupational Exposure , Equipment Design , Humans , Manufactured Materials , Microscopy, Electron , Mineral Fibers , Reference Values , Respiratory Protective Devices , Ventilation
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