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The Hunt bumble bee, Bombus huntii, is a widely distributed pollinator in western North America. The species produces large colony sizes in captive rearing conditions, experiences low parasite and pathogen loads, and has been demonstrated to be an effective pollinator of tomatoes grown in controlled environment agriculture systems. These desirable traits have galvanized producer efforts to develop commercial B. huntii colonies for growers to deliver pollination services to crops. To better understand B. huntii biology and support population genetic studies and breeding decisions, we sequenced and assembled the B. huntii genome from a single haploid male. High-fidelity sequencing of the entire genome using PacBio, along with HiC sequencing, led to a comprehensive contig assembly of high continuity. This assembly was further organized into a chromosomal arrangement, successfully identifying 18 chromosomes spread across the 317.4 Mb assembly with a BUSCO score indicating 97.6% completeness. Synteny analysis demonstrates shared chromosome number (n = 18) with B. terrestris, a species belonging to a different subgenus, matching the expectation that presence of 18 haploid chromosomes is an ancestral trait at least between the subgenera Pyrobombus and Bombus sensu stricto. In conclusion, the assembly outcome, alongside the minimal tissue sampled destructively, showcase efficient techniques for producing a comprehensive, highly contiguous genome.

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Declines in bumble bee species range and abundances are documented across multiple continents and have prompted the need for research to aid species recovery and conservation. The rusty patched bumble bee (Bombus affinis) is the first federally listed bumble bee species in North America. We conducted a range-wide population genetics study of B. affinis from across all extant conservation units to inform conservation efforts. To understand the species' vulnerability and help establish recovery targets, we examined population structure, patterns of genetic diversity, and population differentiation. Additionally, we conducted a site-level analysis of colony abundance to inform prioritizing areas for conservation, translocation, and other recovery actions. We find substantial evidence of population structuring along an east-to-west gradient. Putative populations show evidence of isolation by distance, high inbreeding coefficients, and a range-wide male diploidy rate of ~15%. Our results suggest the Appalachians represent a genetically distinct cluster with high levels of private alleles and substantial differentiation from the rest of the extant range. Site-level analyses suggest low colony abundance estimates for B. affinis compared to similar datasets of stable, co-occurring species. These results lend genetic support to trends from observational studies, suggesting that B. affinis has undergone a recent decline and exhibit substantial spatial structure. The low colony abundances observed here suggest caution in overinterpreting the stability of populations even where B. affinis is reliably detected interannually. These results help delineate informed management units, provide context for the potential risks of translocation programs, and help set clear recovery targets for this and other threatened bumble bee species.

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PURPOSE: The mechanical complications related to ASD remain a concern due to their morbidity and associated revision surgery. Restoration of each patient's Roussouly profile may reduce these. Our aim was to examine if the restoration of the Roussouly profile reduced these complications and revision rates in older patients operated for degenerative ASD. METHODS: Retrospective analysis of a single-centre, 2-year minimum follow-up patient database. All patients undergoing corrective surgery (≥ 4 levels) for ASD were included with analysis of demographic data, operative records, restoration of Roussouly sagittal profile, mechanical complications and revision rates. Univariate and multivariate analysis was conducted. RESULTS: Fifty-two patients were included (mean age was 72.3 years, average follow-up 56.3 months). Twenty-six patients had a "restored" profile (50%) and 26 an "unrestored" profile (50%). The incidence of mechanical complications was 7 (27%) and 23 (88%) for the restored and unrestored groups, respectively (p < 0.001). Revision rates were 4 (15.4%) and 18 (69.2%), respectively (p < 0.000), in the restored and unrestored profiles. Univariate analysis determined that profile restoration and BMI were associated with mechanical complications and revision surgery, whilst only the profile restoration status maintained its statistical power in multivariate analysis (p = 0.002 and p = 0.002, respectively). Age was not a significant factor in univariate analysis. The relative risk for mechanical failure and revision surgery was 5.6 times (CI 1.929-16.39) and 3.08 times (CI 1.642-5.734) greater if the profile was not restored. CONCLUSIONS: Achieving each patient's ideal Roussouly profile is associated with a reduced incidence of mechanical complications and revision rates in the older population after surgery for degenerative ASD.

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The rusty patched bumble bee, Bombus affinis, is an important pollinator in North America and a federally listed endangered species. Due to habitat loss and large declines in population size, B. affinis is facing imminent extinction unless human intervention and recovery efforts are implemented. To better understand B. affinis biology and population genetic and genomic landscapes, we sequenced and assembled the B. affinis genome from a single haploid male. Whole genome HiFi sequencing on PacBio coupled with HiC sequencing resulted in a complete and highly contiguous contig assembly that was scaffolded into a chromosomal context, resolving 18 chromosomes distributed across the 365.1 Mb assembly. All material for both HiFi and HiC sequencing was derived from a single abdominal tissue segment from the single male. These assembly results, coupled with the minimal amount of tissue destructively sampled, demonstrate methods for generating contiguous and complete genomic resources for a rare and endangered species with limited material available and highlight the importance of sample preservation. Precise methods and applications of these methods are presented for potential applications in other species with similar limitations in specimen availability and curation considerations.

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Of the 265 known bumble bee (Bombus) species, knowledge of colony lifecycle is derived from relatively few species. As interest in Bombus commercialization and conservation grows, it is becoming increasingly important to understand colony growth dynamics across a variety of species since variation exists in nest success, colony growth, and reproductive output. In this study, we reported successful nest initiation and establishment rates of colonies and generated a timeline of colony development for 15 western North American Bombus species, which were captively reared from wild-caught gynes from 2009 to 2019. Additionally, we assessed variation in colony size among 5 western North American Bombus species from 2015 to 2018. Nest initiation and establishment rates varied greatly among species, ranging from 5-76.1% and 0-54.6%, respectively. Bombus griseocollis had the highest rates of nest success across the 11-yr period, followed by B. occidentalis, B. vosnesenskii, and B. huntii. Furthermore, days to nest initiation and days to nest establishment varied among species, ranging from 8.4 to 27.7 days and 32.7 to 47 days. Colony size also differed significantly among species with B. huntii and B. vosnesenskii producing more worker/drone cells than B. griseocollis, B. occidentalis, and B. vancouverensis. Additionally, gyne production differed significantly among species with B. huntii colonies producing more gynes than B. vosnesenskii. Results from this study increase knowledge of systematic nesting biology for numerous western North American Bombus species under captive rearing conditions, which can further improve rearing techniques available to conservationists and researchers.

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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.

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Comprehensive decisions on the management of commercially produced bees, depend largely on associated knowledge of genetic diversity. In this study, we present novel microsatellite markers to support the breeding, management, and conservation of the blue orchard bee, Osmia lignaria Say (Hymenoptera: Megachilidae). Native to North America, O. lignaria has been trapped from wildlands and propagated on-crop and used to pollinate certain fruit, nut, and berry crops. Harnessing the O. lignaria genome assembly, we identified 59,632 candidate microsatellite loci in silico, of which 22 were tested using molecular techniques. Of the 22 loci, 12 loci were in Hardy-Weinberg equilibrium (HWE), demonstrated no linkage disequilibrium (LD), and achieved low genotyping error in two Intermountain North American wild populations in Idaho and Utah, USA. We found no difference in population genetic diversity between the two populations, but there was evidence for low but significant population differentiation. Also, to determine if these markers amplify in other Osmia, we assessed 23 species across the clades apicata, bicornis, emarginata, and ribifloris. Nine loci amplified in three species/subspecies of apicata, 22 loci amplified in 11 species/subspecies of bicornis, 11 loci amplified in seven species/subspecies of emarginata, and 22 loci amplified in two species/subspecies of ribifloris. Further testing is necessary to determine the capacity of these microsatellite loci to characterize genetic diversity and structure under the assumption of HWE and LD for species beyond O. lignaria. These markers will inform the conservation and commercial use of trapped and managed O. lignaria and other Osmia species for both agricultural and nonagricultural systems.

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The open-source 2LabsToGo system is the only one in its nature. It combines in one miniaturized instrument all relevant steps normally performed in a chemical and biological laboratory. For the first time, the applicability of the 2LabsToGo system was studied for screening 17 food products. As examples, saccharides were analyzed in eight products of different matrix complexity, and the absence of lactose was studied in nine lactose-free dairy products. Derivatization including homogeneous reagent application and plate heating via the 2LabsToGo system was explored for saccharide detection, and its performance was investigated. The visual detection sensitivity of lactose was comparable to previous studies. The precision of lactose in milk matrix (%RSD 4.6%) as well as the coefficient of determination of the calibration function (0.9995) were highly satisfying. The obtained lactose content of milk (4.5%) was plausible. Screening eight saccharide-containing food samples showed the saccharides in agreement with the expectations for the respective food product. The lactose content of nine different lactose-free dairy products was proven to be below the 0.1% lactose limit value. As proof-of-principle and for verification, these screening results obtained with the miniaturized 2LabsToGo system were reproduced using conventional state-of-the-art instrumentation, which led to the same results. However, instrumental costs were comparably low for the 2LabsToGo system. The application of the new 2LabsToGo system was successfully shown for saccharide screening, which is attractive to the field of quality control or official food control.

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Commercialized bumble bees (Bombus) are primary pollinators of several crops within open field and greenhouse settings. However, the common eastern bumble bee (Bombus impatiens Cresson, 1863) is the only species widely available for purchase in North America. As an eastern species, concerns have been expressed over their transportation outside of their native range. Therefore, there is a need to identify regionally appropriate candidates for commercial crop pollination services, especially in the western U.S.A. In this study, we evaluated the commercialization potential of brown-belted bumble bees (Bombus griseocollis De Geer, 1773), a broadly distributed species throughout the U.S.A., by assessing nest initiation and establishment rates of colonies produced from wild-caught gynes, creating a timeline of colony development, and identifying lab-reared workers' critical thermal maxima (CTMax) and lethal temperature (ecological death). From 2019 to 2021, 70.6% of the wild-caught B. griseocollis gynes produced brood in a laboratory setting. Of these successfully initiated nests, 74.8% successfully established a nest (produced a worker), providing guidance for future rearing efforts. Additionally, lab-reared workers produced from wild-caught B. griseocollis gynes had an average CTMax of 43.5°C and an average lethal temperature of 46.4°C, suggesting B. griseocollis can withstand temperatures well above those commonly found in open field and greenhouse settings. Overall, B. griseocollis should continue to be evaluated for commercial purposes throughout the U.S.A.

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Cuckoo bumble bees (Psithyrus) (Lepeletier, 1832) (Hymenoptera: Apidae) are a unique lineage of bees that depend exclusively on a host bumble bee species to provide nesting material, nutritional resources, and labor to rear offspring. In this study, we document usurpation incidence and population genetic data of Bombus insularis (Smith, 1861) (Hymenoptera: Apidae), a bumble bee species in the Psithyrus subgenus, on field-deployed B. huntii colonies in northern Utah, United States. Within 12 d of deploying B. huntii Greene, 1860 (Hymenoptera: Apidae) colonies at two field sites, 13 of the 16 colonies contained at least one established B. insularis female. Although our results demonstrate that field-deployed bumble bee colonies are highly susceptible to B. insularis usurpation, applying a fabricated excluder to prevent the inquiline from invading a colony was 100% effective. Sibship analysis using microsatellite genotype data of 59 B. insularis females estimates that they originated from at least 49 unique colonies. Furthermore, sibship analysis found siblings distributed between the field sites that were 7.04 km apart. Our result suggests that B. insularis females have the capacity to disperse across the landscape in search of host colonies at distances of at least 3.52 km and up to 7.04 km. Our study underscores the detrimental impact B. insularis usurpation has on the host bumble bee colony. As B. insularis significantly impacts the success of bumble bee colonies, we briefly discuss how the utilization of excluders may be useful for commercial bumble bee colonies that are used to pollinate open field crops.

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Islands are insular environments that are negatively impacted by invasive species. In Hawai'i, at least 21 non-native bees have been documented to date, joining the diversity of >9,000 non-native and invasive species to the archipelago. The goal of this study is to describe the persistence, genetic diversity, and natural history of the most recently established bee to Hawai'i, Megachile policaris Say, 1831 (Hymenoptera: Megachilidae). Contemporary surveys identify that M. policaris is present on at least O'ahu, Maui, and Hawai'i Island, with the earliest detection of the species in 2017. Furthermore, repeated surveys and observations by community members support the hypothesis that M. policaris has been established on Hawai'i Island from 2017 to 2020. DNA sequenced fragments of the cytochrome oxidase I locus identify two distinct haplotypes on Hawai'i Island, suggesting that at least two founders have colonized the island. In their native range, M. policaris is documented to forage on at least 21 different plant families, which are represented in Hawai'i. Finally, ensemble species distribution models (SDMs) constructed with four bioclimatic variables and occurrence data from the native range of M. policaris predicts high habitat suitability on the leeward side of islands throughout the archipelago and at high elevation habitats. While many of the observations presented in our study fall within the predicted habitat suitability on Hawai'i, we also detected the M. policaris on the windward side of Hawai'i Island suggesting that the SDMs we constructed likely do not capture the bioclimatic niche flexibility of the species.

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In all levels of disc herniations the absolute surgical indications include deteriorating neurological deficits with myelopathy or cauda equina syndrome. However, this review summarized the relative indications for surgery in each level.In cervical disc herniation (CDH), the indications for surgery consist of six months of persisting symptoms, not responding to conservative treatment. However, high-quality studies are lacking, and a randomized controlled trial is now underway to clarify the indications.In thoracic disc herniation (TDH), the indications for surgery comprise failure of conservative measures and/or worsening neurological symptoms. Moreover, giant calcified thoracic disc herniations or myelopathy signs on magnetic resonance imaging, even in the absence of neurological symptoms, may benefit from surgical treatment as a preventive measure.In lumbar disc herniation (LDH), the indications for surgery include imaging confirmation of LDH, consistent with clinical findings, and failure to improve after six weeks of conservative care. Cite this article: EFORT Open Rev 2021;6:526-530. DOI: 10.1302/2058-5241.6.210020.

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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.

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Climate change is predicted to increase the risk of biological invasions by increasing the availability of climatically suitable regions for invasive species. Endemic species on oceanic islands are particularly sensitive to the impact of invasive species due to increased competition for shared resources and disease spread. In our study, we used an ensemble of species distribution models (SDM) to predict habitat suitability for invasive bees under current and future climate scenarios in Hawai'i. SDMs projected on the invasive range were better predicted by georeferenced records from the invasive range in comparison to invasive SDMs predicted by records from the native range. SDMs estimated that climatically suitable regions for the eight invasive bees explored in this study will expand by ~934.8% (±3.4% SE). Hotspots for the invasive bees are predicted to expand toward higher elevation regions, although suitable habitat is expected to only progress up to 500 m in elevation in 2070. Given our results, it is unlikely that invasive bees will interact directly with endemic bees found at >500 m in elevation in the future. Management and conservation plans for endemic bees may be improved by understanding how climate change may exacerbate negative interactions between invasive and endemic bee species.

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STUDY DESIGN: A systematic review reporting on the efficacy of an ERAS protocol in patients undergoing spinal fusion for AIS. OBJECTIVE: To systematically evaluate the relevant literature pertaining to the efficacy of ERAS protocols with respect to the length of stay, complication, and readmission rates in patients undergoing posterior spinal corrective surgery for AIS. ERAS is a multidisciplinary approach aimed at improving outcomes of surgery by a specific evidence-based protocol. The rationale of this rapid recovery regimen is to maintain homeostasis so as to reduce the postoperative stress response and pain. No thorough review of available information for its use in AIS has been published. METHODS: A systematic review of the English language literature was undertaken using search criteria (postoperative recovery AND adolescent idiopathic scoliosis) using the PRISMA guidelines (Jan 1999-May 2020). Isolated case reports and case series with < 5 patients were excluded. Length of stay (LOS), complication and readmission rates were used as outcome measures. Statistical analysis was done using the random effects model. RESULTS: Of a total of 24 articles, 10 studies met the inclusion criteria (9 were Level III and 1 of level IV evidence) and were analyzed. Overall, 1040 patients underwent an ERAS-type protocol following posterior correction of scoliosis and were compared to 959 patients following traditional protocols. There was a significant reduction in the length of stay in patients undergoing ERAS when compared to traditional protocols (p < 0.00001). There was no significant difference in the complication (p = 0.19) or readmission rates (p = 0.30). Each protocol employed a multidisciplinary approach focusing on optimal pain management, nursing care, and physiotherapy. CONCLUSION: This systematic review demonstrates advantages with ERAS protocols by significantly reducing the length of stay without increasing the complications or readmission rates as compared to conventional protocols. However, current literature on ERAS in AIS is restricted largely to retrospective studies with non-randomized data, and initial cohort studies lacking formal control groups. LEVEL OF EVIDENCE: 3.

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Bumble bees are an ecologically and economically important group of pollinating insects worldwide. Global climate change is predicted to affect bumble bee ecology including habitat suitability and geographic distribution. Our study aims to estimate the impact of projected climate change on 18 Mesoamerican bumble bee species. We used ecological niche modeling (ENM) using current and future climate emissions scenarios (representative concentration pathway 4.5, 6.0, and 8.5) and models (CCSM4, HadGEM2-AO, and MIROC-ESM-CHEM). Regardless of the scenario and model applied, our results suggest that all bumble bee species are predicted to undergo a reduction in their potential distribution and habitat suitability due to projected climate change. ENMs based on low emission scenarios predict a distribution loss ranging from 7% to 67% depending on the species for the year 2050. Furthermore, we discovered that the reduction of bumble bee geographic range shape will be more evident at the margins of their distribution. The reduction of suitable habitat is predicted to be accompanied by a 100-500 m upslope change in altitude and 1-581 km shift away from the current geographic centroid of a species' distribution. On average, protected natural areas in Mesoamerica cover ~14% of each species' current potential distribution, and this proportion is predicted to increase to ~23% in the high emission climate change scenarios. Our models predict that climate change will reduce Mesoamerican bumble bee habitat suitability, especially for rare species, by reducing their potential distribution ranges and suitability. The small proportion of current and future potential distribution falling in protected natural areas suggests that such areas will likely have marginal contribution to bumble bee habitat conservation. Our results have the capacity to inform stakeholders in designing effective landscape management for bumble bees, which may include developing restoration plans for montane pine oak forests habitats and native flowering plants.

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BACKGROUND: MRI is the most accurate imaging modality for diagnosing knee pathologies. However, there is uncertainty concerning factors predicting false negative MRI, such as meniscal tear patterns as well as patient factors. The aims of this study were to report 1.5-Tesla MRI accuracy of ACL, meniscus and articular cartilage damage and characterize false negative lesions. METHODS: Two hundred eighteen consecutive knee arthroscopies performed in our institution between 2013 and 2016 and their respective prospectively-collected MRI reports were reviewed. Inclusion criteria were age > 15 years-old, primary arthroscopy, 1.5-Tesla MRI performed at the same institution, and time interval MRI-surgery < 6 months. Exclusion criteria were revision arthroscopy and arthroscopic-assisted fracture fixation or multiligament surgery. Accuracy measures and Kappa coefficients were calculated comparing the MRI diagnosis to the arthroscopic findings. Moreover, the arthroscopic findings of false negative MRI were compared to the findings of true positive MRI using the Fisher-exact test. Pearson correlation was used for testing the correlation between MRI accuracy and patient age. RESULTS: The highest accuracy was observed in medial meniscus and in ACL findings. For the medial meniscus sensitivity, specificity, agreement, and Kappa coefficient were 77, 92, 86%, and 0.7, and for the ACL these measures were 82, 97, 87%, and 0.73. MRI accuracy was lower in the lateral meniscus and articular cartilage with Kappa coefficient 0.42 and 0.3, respectively. More specifically, short peripheral tears in the posterior horn of the medial meniscus were characteristic of false negative findings compared to true positive findings of the MRI (p <  0.01). MRI accuracy correlated negatively compared to arthroscopic findings with patient age for the medial meniscus (r = - 0.21, p = 0.002) and for articular cartilage damage (r = - 0.45, p <  0.001). CONCLUSION: 1.5-Tesla MRI will accurately diagnose ACL and medial meniscal tears and can reliably complete the diagnostic workup following physical examination, particularly in young adults. This modality however is not reliable for diagnosing short peripheral tears at the posterior horn of the medial meniscus and partial thickness articular cartilage lesion of the femoral condyles. For these lesions, definitive diagnosis may require cartilage-specific MRI sequences or direct arthroscopic evaluation. LEVEL OF EVIDENCE: Prognostic study, Level III.

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PURPOSE: We report a case of a patient with an acute symptomatic Schmorl node (SN) that spontaneously resolved with characteristic imaging findings. The extensive hematological investigations also allow some insight as to the likely pathophysiology of the painful lesion. METHODS: Case report of an acute symptomatic SN. RESULTS: A fit and athletic 44-year-old female participant in a competitive paddling event developed atypical thoracic pain and was admitted for further investigation. Normal blood results included complete blood cell count, clotting, and D-dimer. Creatine phosphokinase was 63 U/L (reference < 167 U/L) and troponin I levels were not raised. Her only hematological abnormality was an elevated C-reactive protein (CRP) at 60.2 mg/L (reference < 5 mg/L). Magnetic resonance imaging (MRI) scan showed signal hyperintensity involving T7 vertebral body, surrounding an enlarged SN. Patient was given oral nonsteroidal anti-inflammatory drugs, opioid analgesia, and gradually mobilized. After 3 days, the pain had sufficiently subsided and CRP was 17.8 mg/L. Follow-up MRI scan showed some reduction in the T2 hyperintensity and size of the intraosseous herniation. Patient gradually returned to full activities and had no recurrence of symptoms. MRI scan 8 months after the initial scan showed almost complete resolution of the T2 hyperintensity and pan-vertebral marrow edema. CONCLUSION: Symptomatic SN should be part of the differential diagnosis of unexplained thoracolumbar pain. Modality of choice for diagnosis would be MRI. Once diagnosed, several treatment options are available with the most likely being spontaneous resolution of symptoms and bone healing within a few months. The conservative approach is recommended when the symptoms can be medically well controlled.

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Globally, there are only five bumble bee (Hymenoptera: Apidae, Bombus) species that have been successfully commercialized for agriculture. The Hunt bumble bee, Bombus huntii Green, 1860, has been recognized as a suitable pollinator of crops and has a broad distribution in western North America, making it a viable candidate for commercialization. In this study, our goal was to characterize the foraging dynamics of B. huntii female workers under open field conditions. To accomplish this goal, we monitored three B. huntii colonies over an 8-wk period in the summer of 2012 in northern Utah. Using marked bees, we studied the relationship between foraging duration/offloading and pollen/nonvisible pollen collection. In total, we observed 921 foraging events across all three colonies. Of our observations, 82% (n = 756) were foraging events that included both a departure and arrival time observation. Average duration of pollen and nonpollen (i.e., nectar) trips across foragers is 41.86 ± 5.65 min (±SE) and 32.18 ± 5.89 min, respectively. Workers spent a significantly longer time offloading pollen in the nest after a foraging trip relative to workers without pollen present on their corbicula. Pollen foraging rate increases over the course of the day, likely due to the time it takes to learn how to forage on a diverse array of flower morphologies. Our study provides data on how long it takes for B. huntii to forage in open field conditions and will be useful when comparing foraging rates in controlled crop systems.

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OBJECTIVE: To test whether patients with spontaneous osteonecrosis of the knee (SONK) are characterized by abnormal levels of thrombophilia-associated factors. DESIGN: Twenty-five patients with SONK were recruited. Inclusion criteria were (1) age >40 years, (2) acute onset knee pain not precipitated by trauma, and (3) MRI findings consistent with SONK. Exclusion criteria were (1) history of cancer and chemotherapy and (2) factors associated with secondary osteonecrosis. Blood tests included 13 thrombophilia-associated factors that were either heritable mutations or acquired factors. Descriptive statistics included medians, ranges, means, and standard deviations. Mann-Whitney test was used to compare thrombophilia-associated factor levels between the sexes. Spearman's rank test was used to test correlations between smoking status and each thrombophilia-associated factor. Level of significance was set at 0.05. RESULTS: Median patient age was 62 years (range, 44-77 years). There were 16 (64%) men. Thirteen (52%) patients had thrombophilia-associated factor abnormalities of which 9 were elevated fibrinogen but this was less than 1 standard deviation above norm threshold. Other findings were 3 patients with marginally decreased antithrombin below norm threshold, low protein S Ag in only 1 patient, and factor V Leiden mutation heterozygosity in 2 patients, which was not higher than normal population prevalence. Thrombophilia-associated factors neither differed between sexes ( P = nonsignificant) nor correlated with smoking status ( P = nonsignificant). CONCLUSION: Thrombophilia-associated factor abnormalities in patients with SONK were minimal. Therefore, clinical workup and treatment strategy in this disease should focus on addressing alternative etiologies leading to abnormal subchondral bone metabolism with focal osteopenia.

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