Targeted resequencing of a genomic region influencing tameness and aggression reveals multiple signals of positive selection.

The identification of the causative genetic variants in quantitative trait loci (QTL) influencing phenotypic traits is challenging, especially in crosses between outbred strains. We have previously identified several QTL influencing tameness and aggression in a cross between two lines of wild-derived, outbred rats (Rattus norvegicus) selected for their behavior towards humans. Here, we use targeted sequence capture and massively parallel sequencing of all genes in the strongest QTL in the founder animals of the cross. We identify many novel sequence variants, several of which are potentially functionally relevant. The QTL contains several regions where either the tame or the aggressive founders contain no sequence variation, and two regions where alternative haplotypes are fixed between the founders. A re-analysis of the QTL signal showed that the causative site is likely to be fixed among the tame founder animals, but that several causative alleles may segregate among the aggressive founder animals. Using a formal test for the detection of positive selection, we find 10 putative positively selected regions, some of which are close to genes known to influence behavior. Together, these results show that the QTL is probably not caused by a single selected site, but may instead represent the joint effects of several sites that were targets of polygenic selection.

Calorimetric Observation of Single He 2 ∗ Excimers in a 100-mK He Bath.

We report the first calorimetric detection of individual He 2 ∗ excimers within a bath of superfluid 4 He . The detector used in this work is a single superconducting titanium transition edge sensor (TES) with an energy resolution of ∼ 1 eV , immersed directly in the helium bath. He 2 ∗ excimers are produced in the surrounding bath using an external gamma-ray source. These excimers exist either as short-lived singlet or long-lived triplet states. We demonstrate detection (and discrimination) of both states: In the singlet case the calorimeter records the absorption of a prompt ≈ 15 eV photon, and in the triplet case the calorimeter records a direct interaction of the molecule with the TES surface, which deposits a distinct fraction of the ≈ 15 eV , released upon decay, into the surface. We also briefly discuss the detector fabrication and characterization.

Rock climbing injuries.

Three-quarters of elite and recreational sport climbers will suffer upper extremity injuries. Approximately 60% of these injuries will involve the hand and wrist, the other 40% will be equally divided between the elbow and the shoulder. Most injuries will be tendonopathies secondary to strains, microtrauma or flexor retinacular irritation. However, up to 30% of these injuries in up to 50% of elite climbers will involve the proximal interphalangeal (PIP) region. These injuries are more serious and consist of varying degrees of flexor digitorum sublimis insertional strains, digital fibro-osseous sheath ruptures and PIP joint collateral ligament strains. Early changes in climbing schedules, stretching and exercise habits, and protective digital taping are necessary to protect and rehabilitate these athletes.

Compartment pressure in association with closed tibial fractures. The relationship between tissue pressure, compartment, and the distance from the site of the fracture.

We studied twenty-five consecutive patients who had a closed tibial fracture to determine whether there was a relationship between compartment pressure and the distance at which the pressure was measured from the site of the fracture. Tissue pressure was measured in all four compartments of the leg at the level of the fracture and at five-centimeter increments proximal and distal to the fracture. The peak pressure was usually found at the level of the fracture and was always located within five centimeters of the fracture. The highest pressures were recorded in the anterior and the deep posterior compartments in twenty patients, including all five of those who had had a fasciotomy. The measured pressure decreased steadily when sampled at increasing distances proximal and distal to the site of the highest recorded pressure. Decreases of twenty millimeters of mercury (2.67 kilopascals) five centimeters adjacent to the site of the peak pressure were common. Compartment syndrome was diagnosed in five patients on the basis of clinical findings, and the diagnosis was confirmed when peak compartment pressures of more than the critical threshold (within twenty millimeters of mercury [2.67 kilopascals] of the diastolic blood pressure) were recorded. Three of these five patients had measured pressures that were less than the critical threshold within five centimeters of the site of the peak pressure. Failure to measure tissue pressure within a few centimeters of the zone of peak pressure may result in a serious underestimation of the maximum compartment pressure. Our results suggest that measurements should be performed in both the anterior and the deep posterior compartments at the level of the fracture as well as at locations proximal and distal to the zone of the fracture to determine reliably the location of the highest tissue pressure in a lower extremity when a compartment syndrome is suspected clinically. The highest pressure should be used in the decision-making process.

Myoelectric prostheses. A long-term follow-up and a study of the use of alternate prostheses.

Forty-four patients who had had a total of forty-seven amputations of an upper extremity and who had had a myoelectric prosthesis for more than two years were evaluated retrospectively for the amount of use of the prosthesis, the use of any other prosthesis, and the demographic factors that might be related to use of the prosthesis. The average duration of follow-up was five years (range, twenty-five months to seventeen years). Forty of the forty-four patients also had a conventional prosthesis. Twenty-two patients (50 per cent) rejected the myoelectric prosthesis completely; thirteen (32 per cent) of the forty patients who also had a conventional prosthesis rejected the conventional prosthesis completely. The patients who used the myoelectric device the least were employed in occupations that required high-demand use of the prosthesis (lifting of more than 4.5 kilograms [ten pounds] or repetitive manual labor) or were receiving or seeking Workers' Compensation, or both.

Injury patterns in recreational rock climbers.

We studied 39 recreational rock climbers to determine the incidence and pattern of injuries sustained in the sport at their level. Eleven climbers (26%), who climbed beyond the sport level, had sustained a major injury from a fall. Thirty-five climbers (89%) sustained at least one significant injury. Fifty percent of the injuries involved the hand or wrist. Only seven climbers (19%) had evidence of a digital pulley injury (climber's finger). Four climbers (11%) had evidence of a carpal tunnel syndrome. Twenty climbers (50%) had tendinitis in an upper extremity on physical examination.

Coverage problems of the foot and ankle.

Difficult wound coverage problems about the foot and ankle can occur secondary to trauma, osteomyelitis, foot deformities, tumors, or neuropathies (in particular, diabetes mellitus). Coverage can be difficult because of the special weight-bearing properties of the foot, the lack of intervening muscle between the skeletal elements and the integument, and the limited mobility of the overlying integument. Sorting out the 40 to 50 flap options for the foot and ankle requires a classification that describes the wound, the patient, and the available surgical options. The wound is classified based on size, anatomic location, and the presence or absence of infection. The anatomic location also describes the weight-bearing characteristics of the wound. Associated arterial, nerve and skeletal injuries are noted. A very small wound is less than 2 X 2 cm. A small wound is from 2 X 2 to 4 X 5 cm. A medium wound is from 4 X 5 to 7 X 7 cm. A large wound is from 7 X 7 to 10 X 20 cm, and a very large wound is from 10 X 20 up to 15 X 40 cm. Does the wound involve weight-bearing skin? Patient considerations include age and the presence of systemic or local compromise. Tobacco use, cosmetic concerns, occupation, rehabilitation potential, and amputee prejudices should be ascertained. Flap options can be classified as local transpositional, island pedicle, distant pedicle, and free-tissue transfers. The flaps may or may not incorporate muscle that may be needed for revascularization and dead space management in osteomyelitis. Some flaps are inappropriate because of local artery or nerve injuries. Some flaps will provide sensate coverage, and others can provide reinnervation potential. The potential to create new neuromas, ease of dissection, flap reliability, and cosmesis of the donor site are all important considerations.

Anterior sleeve fracture of the capitellum.

The case of an articular sleeve fracture of the capitellum in an 8-year-old girl is presented. An accurate diagnosis of this injury and its extent was able to be made preoperatively only by arthrography. The use of arthography in injuries about the elbow in children is recommended.

Neuropathic arthropathy of the shoulder. A case report.

A case of neuropathic arthropathy of the shoulder secondary to syringomyelia is presented. The classic clinical and radiographic features of the entity are illustrated. Emphasis is made on the use of magnetic resonance imaging in evaluation. Neuropathic arthropathy should be considered in the evaluation of shoulder pain or instability.