A Comparison of Visual and Genetic Techniques for Identifying Japanese Marten Scats - Enabling Diet Examination in Relation to Seasonal Food Availability in a Sub-Alpine Area of Japan.

We compared the reliability of visual diagnostic criteria to DNA diagnostic techniques, including newly designed primers, to discriminate Japanese marten (Martes melampus) feces from those of other sympatric carnivore species. Visual criteria proved > 95% reliable for fresh, odoriferous scats in good condition. Based upon this verification, we then examined if and how Japanese marten diet differs among seasons at high elevation study site (1500-2026 m). We also considered how intra-specific competition with the Japanese red fox (Vulpes vulpes japonica) may shape marten feeding ecology. From 120 Japanese marten fecal samples, high elevation diet comprised (frequency of occurrence) 30.6-66.0% mammals, 41.0-72.2% insects and 10.6-46.2% fruits, subject to seasonal variation, with a Shannon-Weaver index value of 2.77. These findings contrast substantially to seasonal marten diet reported in adjacent lowland regions (700-900 m), particularly in terms of fruit consumption, showing the trophic adaptability of the Japanese marten. We also noted a substantial dietary overlap with the red fox (n = 26 scats) with a Shannon-Weaver index of 2.61, inferring little trophic niche mutual exclusion (trophic niche overlap: 0.95), although some specific seasonal prey selection differences were likely related to relative differences in body size between foxes and martens. This additional information on the feeding ecology of the Japanese marten enables a better assessment of the specific risks populations face in mountainous regions.

The Nature and Clinical Significance of Preinjury Recall Bias Following Mild Traumatic Brain Injury.

OBJECTIVE: Patients with mild traumatic brain injury (MTBI) often underestimate their preinjury symptoms. This study aimed to clarify the mechanism underlying this recall bias and its contribution to MTBI outcome. SETTING: Level I trauma center. PARTICIPANTS: Patients with uncomplicated MTBI (N = 88) and orthopedic injury (N = 67). DESIGN: Prospective longitudinal. MAIN MEASURES: Current and retrospective ratings on the British Columbia Postconcussion Symptom Inventory, completed at 6 weeks and 1 year postinjury. RESULTS: Preinjury symptom reporting was comparable across groups, static across time, and associated with compensation-seeking. High preinjury symptom reporting was related to high postinjury symptom reporting in the orthopedic injury group but less so in the MTBI group, indicating a stronger positive recall bias in highly symptomatic MTBI patients. Low preinjury symptom reporting was not a risk factor for poor MTBI outcome. CONCLUSION: The recall bias was stronger and more likely clinically significant in MTBI patients with high postinjury symptoms. Multiple mechanisms appear to contribute to recall bias after MTBI, including the reattribution of preexisting symptoms to MTBI as well as processes that are not specific to MTBI (eg, related to compensation-seeking).