Search Results (3)

Despite their large size and striking markings, the identification of bumble bees (Bombus spp.) is surprisingly difficult. This is particularly true for three North American sympatric species in the subgenus Pyrobombus that are often misidentified: B. sandersoni Franklin, B. vagans Smith B. perplexus Cresson. Traditionally, the identification of these cryptic species was based on observations of differences in hair coloration and pattern and qualitative comparisons of morphological characters including malar length. Unfortunately, these characteristics do not reliably separate these species. We present quantitative morphometric methods to separate these species based on the malar length to width ratio (MRL) and the ratios of the malar length to flagellar segments 1 (MR1) and 3 (MR3) for queens and workers, and validated our determinations based on DNA barcoding. All three measurements discriminated queens of B. sandersoni and B. vagans with 100% accuracy. For workers, we achieved 99% accuracy by combining both MR1 and MR3 measurements, and 100% accuracy differentiating workers using MRL. Moreover, measurements were highly repeatable within and among both experienced and inexperienced observers. Our results, validated by genetic evidence, demonstrate that malar measurements provide accurate identifications of B. vagans and B. sandersoni. There was considerable overlap in the measurements between B. perplexus and B. sandersoni. However, these species can usually be reliably separated by combining malar ratio measurements with other morphological features like hair color. The ability to identify bumble bees is key to monitoring the status and trends of their populations, and the methods we present here advance these efforts. Full article

Nasal fractures account for up to 58% of facial fractures. However, the literature characterizing associated injuries and risk factors for nasal fractures is sparse and is mostly composed of single-center experiences. This study sought to provide a large descriptive analysis and identify associated injuries and risk factors for nasal fractures in trauma using a national database. A retrospective analysis of the National Trauma Data Bank (NTDB) from 2007 to 2015 was performed. Patients ≥ 18 years of age with nasal fractures were included. A multivariable logistic regression model was used to identify predictors for nasal fracture in trauma. Of 5,494,609 trauma patients in the NTDB, 255,533 (4.6%) had a nasal fracture. Most were male (74.8%) with a mean age of 45.6 years. Blunt trauma accounted for 90.5% of fractures, with motor vehicle accident being the most common mechanism (27.5%). Closed fractures occurred in 93.0% of patients. Concomitant injuries included traumatic brain injury (TBI; 56.9%), malar/maxillary fracture (27.9%), and open wound of the face (38.6%) and nose (9.5%). Of all patients, 10.1% underwent closed or open reductions at index hospitalization. The strongest associated injuries with nasal fracture included open wound of the nose (odds ratio [OR]: 8.71, 95% confidence interval [CI]: 8.49–8.94, p < 0.001), epistaxis (OR: 5.26, 95% CI: 4.59–6.02, p < 0.001), malar/maxillary fracture (OR: 4.38, 95% CI: 4.30–4.45, p < 0.001), and orbital fracture (OR: 3.99, 95% CI: 3.91–4.06, p < 0.001). Nasal fractures are common traumatic injuries with more than 90% occurring by blunt mechanism and over half suffering from a concomitant TBI. The strongest associated injury with nasal fracture is an open wound of the nose. Full article

Objective: To evaluate how malar fat pad (MFP) volumes vary with age, after controlling for gender and body mass index (BMI). Study Design: A prospective case–control study evaluating volume of the MFP in women of two age groups. Methods: Soft tissue dimensions were measured in eight subjects using magnetic resonance imaging. A multiplanar localizing sequence, followed in sagittal and coronal orientations using a turbo spin echo sequence, was performed to define the MFP. Volumetric calculations were then performed using a 3D image analysis application (Dextroscope, Volume Interactions, Republic of Singapore) to circumscribe areas, orient dimensions, and calculate volumes of the MFP. Results: These data reveal no significant difference in the mean (standard deviation) right MFP (p = 0.50), left MFP (p = 0.41), or total MFP (p = 0.45) volumes when comparing the two age groups. In addition, these data indicate that there was no correlation between age and total MFP volume (Pearson correlation coefficient 0.27). Moreover, there was no correlation between age and the ratio of total volume/BMI (Pearson correlation coefficient −0.18). Conclusions: Although the sample size of this study was small, these data indicate that ptosis of midfacial fat is more important than volume loss inmidfacial aging. These data would suggest repositioning as the primary modality for craniofacial reconstruction. Full article