Phonon Laser in the Quantum Regime.

We demonstrate a trapped-ion system with two competing dissipation channels, implemented independently on two ion species cotrapped in a Paul trap. By controlling coherent spin-oscillator couplings and optical pumping rates we explore the phase diagram of this system, which exhibits a regime analogous to that of a (phonon) laser but operates close to the quantum ground state with an average phonon number of n[over ¯]<10. We demonstrate phase locking of the oscillator to an additional resonant drive, and also observe the phase diffusion of the resulting state under dissipation by reconstructing the quantum state from a measurement of the characteristic function.

Cervical spine injury after virtual reality gaming: a case report.

BACKGROUND: We report a patient who fractured the seventh cervical vertebra while playing a virtual reality (VR) game, without any other trauma. This case report aims to describe the spinal trauma incurred during the use of a VR headset in a video game. CASE PRESENTATION: The Caucasian patient presented with pain and swelling in the lower cervical spine at our clinic after playing a video game involving a combination of shoulder, arm and head movements while wearing a VR headset. Preexisting comorbidities were not present in the 31-year-old male. No history of regular medication use or drug abuse was recorded. After performing a clinical examination and radiological diagnostics, we found a dislocated traumatic fracture of the spinous process of the seventh cervical vertebra. After a soft tissue defect was excluded through magnetic resonance imaging (MRI) diagnostics, a conservative therapy regimen with pain therapy and immobilization was started. After hospitalization, outpatient controls were conducted at 4, 6 and 12 weeks. At 6 weeks after hospitalization, the patient had recovered from the injury without complications. CONCLUSIONS: Rapid movements during VR gaming can lead to injuries of the cervical spine. In addition to rapid movements, the additional weight of the VR headset as well as the decoupling of audiovisual stimuli from the perceived proprioceptive information should be considered. Determining whether this is an isolated incident induced by unknown preexisting factors or whether the trauma mechanism alone can lead to severe spinal trauma needs to be studied further with additional cases.

Nocturnal Gamma-Hydroxybutyrate Reduces Cortisol-Awakening Response and Morning Kynurenine Pathway Metabolites in Healthy Volunteers.

BACKGROUND: Gamma-hydroxybutyrate (GHB; or sodium oxybate) is an endogenous GHB-/gamma-aminobutyric acid B receptor agonist. It is approved for application in narcolepsy and has been proposed for the potential treatment of Alzheimer's disease, Parkinson's disease, fibromyalgia, and depression, all of which involve neuro-immunological processes. Tryptophan catabolites (TRYCATs), the cortisol-awakening response (CAR), and brain-derived neurotrophic factor (BDNF) have been suggested as peripheral biomarkers of neuropsychiatric disorders. GHB has been shown to induce a delayed reduction of T helper and natural killer cell counts and alter basal cortisol levels, but GHB's effects on TRYCATs, CAR, and BDNF are unknown. METHODS: Therefore, TRYCAT and BDNF serum levels, as well as CAR and the affective state (Positive and Negative Affect Schedule [PANAS]) were measured in the morning after a single nocturnal dose of GHB (50 mg/kg body weight) in 20 healthy male volunteers in a placebo-controlled, balanced, randomized, double-blind, cross-over design. RESULTS: In the morning after nocturnal GHB administration, the TRYCATs indolelactic acid, kynurenine, kynurenic acid, 3-hydroxykynurenine, and quinolinic acid; the 3-hydroxykynurenine to kynurenic acid ratio; and the CAR were significantly reduced (P < 0.05-0.001, Benjamini-Hochberg corrected). The quinolinic acid to kynurenic acid ratio was reduced by trend. Serotonin, tryptophan, and BDNF levels, as well as PANAS scores in the morning, remained unchanged after a nocturnal GHB challenge. CONCLUSIONS: GHB has post-acute effects on peripheral biomarkers of neuropsychiatric disorders, which might be a model to explain some of its therapeutic effects in disorders involving neuro-immunological pathologies. This study was registered at ClinicalTrials.gov as NCT02342366.

Patient-centered quality of life measures after alloplastic temporomandibular joint replacement surgery.

The purpose of this study was to evaluate patient-reported outcome measures of quality of life (QoL) for patients with end-stage temporomandibular joint (TMJ) disease who have undergone TMJ prosthetic replacement. The records of 36 patients who had undergone alloplastic total joint replacement procedures were analyzed. Patients were treated using either TMJ Concepts or Biomet/Lorenz prosthetics. Patients were asked to complete a 12-item TMJ-S-QoL survey, which encompassed questions pertaining to pain, speech, chewing function, and various aspects of social life and mental health. The questions were answered on a 5-point scale. Data were analyzed using the Wilcoxon signed-rank test. Among the 36 patients (six male and 30 female), 18 responded to the survey. Markers of QoL after surgery were compared to the preoperative period. Significant improvements were reported for pain (94.4% of patients), chewing (83.3% of patients), speech (55.6% of patients), anxiety (72.2% of patients), activity (66.7% of patients), recreation (61.1% of patients), and mood (66.7% of patients) (all P<0.05). TMJ prosthetic replacement significantly enhanced QoL among patients suffering from chronic pain, limited range of motion, anxiety, impaired speech, and chewing due to end-stage TMJ disease in this sample of surgical patients.

Ameloblastic carcinoma with features of ghost cell odontogenic carcinoma in a patient with suspected Gardner syndrome.

Ameloblastic carcinoma and ghost cell odontogenic carcinoma are rare malignancies arising in odontogenic epithelium within the jaws. Gardner syndrome is a multifaceted autosomal dominant condition, which results in multiple dentofacial anomalies along with premalignant colon polyp formation and tumor formation in the skin and other organs. We report a case of ameloblastic carcinoma with features of ghost cell odontogenic carcinoma and extensive clear cell change and melanin pigmentation in a patient with clinical features of Gardner syndrome. To the best of our knowledge, odontogenic carcinoma arising in a patient with features of Gardner syndrome has not been reported previously. The clinical, radiographic, and histologic features of the case are discussed along with a review of the relevant literature.

Duty-related risk of sudden cardiac death among young US firefighters.

BACKGROUND: Little is known regarding duty-related risks for sudden cardiac death (SCD) among young firefighters. AIMS: To investigate duty-related SCD among US firefighters aged 45 or younger. METHODS: We collected data on duty-related SCD from the US Fire Administration (USFA) and the US National Institute for Occupational Safety and Health (NIOSH). Two physicians independently reviewed each record. The proportions of time spent by firefighters performing specific duties were estimated from a municipal department, 17 large metropolitan departments and a national database. We estimated the duty-specific relative risks (RRs) and 95% confidence intervals (95% CI) of SCD relative to non-emergency duties based on the observed deaths and the expected average proportions of time per duty. RESULTS: The USFA recorded 205 age-eligible on-duty SCDs between 1996 and 2012; 86 (42%) of these deaths and one additional SCD were investigated by NIOSH (total n = 206). NIOSH was more likely (P < 0.001) to report on SCD associated with physical training (69% of cases were investigated) and fire suppression (57%). Compared with non-emergency duties, the risk of SCD was increased for fire suppression (RR 22.1, 95% CI 14.8-32.9), alarm response (RR 2.6, 95% CI 1.5-4.6), alarm return (RR 4.1, 95% CI 2.7-6.2) and physical training (RR 4.8, 95% CI 3.2-7.2). RRs for SCD were higher among firefighters with a pre-existing history of a cardiac condition. All 16 SCDs associated with alarm response occurred among volunteer firefighters. CONCLUSIONS: The performance of strenuous emergency duties is strongly associated with an increased risk of SCD among young firefighters, particularly among those with a history of cardiovascular disease.

Halitosis as a product of hepatic disease.

OBJECTIVES: This study evaluated halitosis in patients suffering from hepatic disease. MATERIAL AND METHODS: Twenty-five patients (12 males and 13 females) aged between 16 and 73 years who had undergone treatment for liver disease were included in this study. Three halimeter recordings were performed to measure methyl mercarptan and hydrogen sulphite. Mean values were calculated and compared with normal values (75-120 ppb). The level of significance was set at P < .05. Results: Thirteen of the 25 subjects (52%) had normal Volatile Sulphur Compound (VSC) values (75-120 ppb). Twelve subjects (48%) recorded values ranging from 132 to 1112 ppb. There was no correlation between hepatic pathology and halitosis. Fifty-two percent of all subjects had poor oral hygiene, strongly correlated with high VSC values (P<0.05) whereas the remaining 48% with good hygiene had normal levels of VSC. CONCLUSIONS: Within the limitations of this study, high values of VSC were not associated with the presence of hepatic disease.

Treatment of long term anterior dislocation of the TMJ.

Acute dislocation of the temporomandibular joint (TMJ) is a relatively common occurrence; chronic long-term dislocation is rare. Variance in the duration of dislocation and anatomical considerations make the treatment for long-standing dislocation complex and controversial. This paper attempts to review the literature associated with chronic TMJ dislocation treatment options and presents the authors' experience with a particularly long term dislocation.

Low fitness is associated with exercise abnormalities among asymptomatic firefighters.

BACKGROUND: Low cardiorespiratory fitness (CRF) has been repeatedly linked to cardiovascular morbidity and mortality, while higher CRF levels are protective. This relationship is likely to be highly relevant in firefighters, who have increased risk of cardiovascular disease (CVD) mortality during strenuous emergencies, which can require prolonged periods of near-maximal heart rates (HR) and high workloads. Abnormalities during maximal stress testing could mark future CVD risk during strenuous duties. AIMS: To determine if low CRF among asymptomatic firefighters is associated with higher risk of electrocardiographic (ECG) and autonomic abnormalities during maximal exercise stress testing and recovery. METHODS: Male career firefighters completed a maximal stress test exercising to volitional exhaustion (mean maximal age-predicted HR achieved 98%, standard deviation (SD) = 6.5). CRF was measured as maximal metabolic equivalents (METS) achieved. Abnormal exercise tests included the following: abnormal HR recovery; chronotropic insufficiency; exaggerated blood pressure response; and ECG abnormalities. The relationship of CRF to stress testing abnormalities was analysed using peak METS categories and peak METS as a continuous variable after adjusting for age, body mass index (BMI) and metabolic syndrome (MetSyn). RESULTS: There were 1149 study participants. CRF was inversely associated with the risk of both ECG and autonomic exercise testing abnormalities before and after adjustment for age, BMI and MetSyn. CONCLUSIONS: Firefighters with lower CRF are significantly more prone to exhibit abnormal stress test parameters, which may indicate higher future risk of cardiovascular events. As such, firefighters with low CRF (≤ 12 METS) should receive cardiovascular risk reduction, including efforts to improve their CRF.

Pseudoaneurysm of the external carotid artery secondary to subcondylar fracture.

Arterial pseudoaneurysms are rare in oral and maxillofacial surgery, but when they occur, quick recognition and management is necessary to avoid devastating consequences. The authors report a case of a pseudoaneurysm of the external carotid artery that developed after open reduction and internal fixation of a mandibular condyle fracture.

[Manipulation of the step borer as cause of too shallow boring depth in the femoral neck with the gamma nail system]. / Handhabung des Stufenbohrers als Ursache für eine zu geringe Bohrtiefe im Schenkelhals beim Gamma-Nagelsystem.

The gamma nail step drill has been sold over 500,000 times worldwide. Depending on the construction used and the way it is handled, it can lead to a drill depth in the femoral head that is too shallow if the anatomic dimension of the femoral neck is rather long. Whenever the relationship between rotational speed and drive force is unfavorable, as it is by hand reaming, the triple-bladed drill only produces a triangular hole in the lateral cortical bone. Subsequently, it draws itself through this hole like a screw, without forming the hole into a complete circle. The drill shaft expands conically along its length preventing it from passing through the hole in the cortical bone at a depth of 90 mm. Until now, this phenomenon has been traced back to blunt drills or perhaps curved guide wires. Since the lag screws that have been used could not be screwed into undrilled cancellus bone, screws have sometimes been implanted at a sub-optimal length. The problem was noticed, however, and documented in experiments, and potential solutions were proposed.

Ca2+ fluorescence imaging with pico- and femtosecond two-photon excitation: signal and photodamage.

The signal and limitations of calcium florescence imaging using nonresonant multiphoton absorption of near-infrared femto- and picosecond laser pulses were examined. The fluorescence changes of various Ca(2+)-indicators induced by transient increases of the intradendritic calcium concentration were evaluated by evoking physiological activity in neocortical neurons in rat brain slices. Photodamage was noticeable as irreversible changes in the parameters describing the calcium fluorescence transients. At higher two-photon excitation rates, a great variety of irregular functional and structural alterations occurred. Thus, signal and observation time were limited by phototoxic effects. At lower excitation rates, photodamage accumulated linearly with exposure time. Femtosecond and picosecond laser pulses were directly compared with respect to this cumulative photodamage. The variation of the pulse length at a constant two-photon excitation rate indicated that a two-photon excitation mechanism is mainly responsible for the cumulative photodamage within the investigated window of 75 fs to 3.2 ps. As a direct consequence, at low excitation rates, the same image quality is achieved irrespective of whether two-photon Ca(2+)-imaging is carried out with femto- or picosecond laser pulses.

Electrocautery-ignited endotracheal tube fire: case report.

The risk of fire in the airway associated with laser surgery is well known, but there are reports of endotracheal tube fires ignited by electrocautery, particularly during pharyngeal surgery or tracheostomy or both. This uncommon complication has potentially devastating consequences. Surgeons undertaking these procedures should be aware of this complication and be familiar with measures to avoid them. We present a case report of an electrocautery-ignited endotracheal tube fire during an elective tracheostomy, which resulted in the patient's death.

Accuracy of orthognathic evaluation using telemedicine technology.

OBJECTIVE: Telemedicine technology has the ability to project highly specialized medical and dental expertise anywhere in the world. This is particularly important to many small, isolated communities that do not have access to medical and dental specialists. Telemedicine also has the potential to reduce unnecessary travel, time away from work, and unneeded hospital admissions. For this technology to be successful, however, clinicians need to have confidence in its capabilities. This study was conducted to determine the accuracy of an orthognathic evaluation using telemedicine. MATERIALS AND METHODS: Thirteen patients were randomly selected for review by two surgeons each using telemedicine and clinical examinations. Clinically acceptable differences were established, and the results of the two examination methods were compared. RESULTS: A main effect of the examination method was observed in 7 of the 18 continuous measurements taken. Examination of the absolute value of the within-subject difference between the two examination methods demonstrated that the mean absolute difference was statistically different from zero for 13 of 18 measurements taken. CONCLUSIONS: These data demonstrate that a relatively accurate orthognathic examination can be performed with this technology. With this in mind, clinicians may feel comfortable using this technology for other clinical applications.