Probing site-resolved correlations in a spin system of ultracold molecules.

Synthetic quantum systems with interacting constituents play an important role in quantum information processing and in explaining fundamental phenomena in many-body physics. Following impressive advances in cooling and trapping techniques, ensembles of ultracold polar molecules have emerged as a promising platform that combines several advantageous properties1-11. These include a large set of internal states with long coherence times12-17 and long-range, anisotropic interactions. These features could enable the exploration of intriguing phases of correlated quantum matter, such as topological superfluids18, quantum spin liquids19, fractional Chern insulators20 and quantum magnets21,22. Probing correlations in these phases is crucial to understanding their properties, necessitating the development of new experimental techniques. Here we use quantum gas microscopy23 to measure the site-resolved dynamics of quantum correlations of polar 23Na87Rb molecules confined in a two-dimensional optical lattice. By using two rotational states of the molecules, we realize a spin-1/2 system with dipolar interactions between particles, producing a quantum spin-exchange model21,22,24,25. We study the evolution of correlations during the thermalization process of an out-of-equilibrium spin system for both spatially isotropic and anisotropic interactions. Furthermore, we examine the correlation dynamics of a spin-anisotropic Heisenberg model engineered from the native spin-exchange model by using periodic microwave pulses26-28. These experiments push the frontier of probing and controlling interacting systems of ultracold molecules, with prospects for exploring new regimes of quantum matter and characterizing entangled states that are useful for quantum computation29,30 and metrology31.

Intensive Mindfulness Meditation Reduces Frequency and Burden of Migraine: An Unblinded Single-Arm Trial.

Objectives: Preventing migraine headaches and improving the quality of life for patients with migraine remains a challenge. We hypothesized intensive meditation training would reduce the disease burden of migraine. Method: An unblinded trial was analyzed as a single cohort exposed to a silent 10-day Vipassana meditation retreat that included 100 hr of sitting meditation. Participants with chronic or episodic migraine were enrolled and followed for 1 year. The primary outcome was a change in mean monthly migraine days at 12 months from baseline. Secondary outcomes included headache frequency and intensity, acute medication use, work days missed, home meditation, sleep quality, general health, quality of life, migraine impact, positive and negative affect, perceived stress, mindfulness, and pain catastrophizing. Results: Three hundred people were screened and 58 (19%) agreed to participate and enrolled in the intensive meditation training. Forty-six participants with chronic migraine (≥ 15 headaches/month of which ≥ 8 were migraines) and 12 with episodic migraine (< 15 and ≥ 4 migraines/month) attended and 45 (78%) completed the retreat. At 12 months, the average migraine frequency was reduced by 2.7 days (from 16.6 at baseline) per 28 days (95%CI - 4.3, - 1.3) and headaches by 3.4 (20.1 at baseline) per 28 days (- 4.9, - 1.9). Fifty percent responder rate was 29% for migraine. Acute medication use dropped by an average of 2.2 days (- 3.9, - 0.5) per 28 days, and participants reported 2.3 fewer days (- 4.0, - 0.5) on which they reduced their activity due to migraines. The most striking and promising effects were in several secondary outcomes, including migraine-specific quality of life, pain catastrophizing, and perceived stress. The significant improvements observed immediately following the intervention were sustained at 12 months follow-up. Conclusions: Training in Vipassana meditation via a 10-day retreat may reduce the frequency and burden of migraine. Preregistration: ClinicalTrials.gov: NCT00663585.

Tagged actin mRNA dysregulation in IGF2BP1[Formula: see text] mice.

Gene expression is tightly regulated by RNA-binding proteins (RBPs) to facilitate cell survival, differentiation, and migration. Previous reports have shown the importance of the Insulin-like Growth Factor II mRNA-Binding Protein (IGF2BP1/IMP1/ZBP1) in regulating RNA fate, including localization, transport, and translation. Here, we generated and characterized a knockout mouse to study RBP regulation. We report that IGF2BP1 is essential for proper brain development and neonatal survival. Specifically, these mice display disorganization in the developing neocortex, and further investigation revealed a loss of cortical marginal cell density at E17.5. We also investigated migratory cell populations in the IGF2BP1[Formula: see text] mice, using BrdU labeling, and detected fewer mitotically active cells in the cortical plate. Since RNA localization is important for cellular migration and directionality, we investigated the regulation of ß-actin messenger RNA (mRNA), a well-characterized target with established roles in cell motility and development. To aid in our understanding of RBP and target mRNA regulation, we generated mice with endogenously labeled ß-actin mRNA (IGF2BP1[Formula: see text]; ß-actin-MS2[Formula: see text]). Using endogenously labeled ß-actin transcripts, we report IGF2BP1[Formula: see text] neurons have increased transcription rates and total ß-actin protein content. In addition, we found decreased transport and anchoring in knockout neurons. Overall, we present an important model for understanding RBP regulation of target mRNA.

Understanding whether chronic lower back pain patients with lumbar spinal stenosis benefit from multiple epidural steroid injections prior to the mild® Procedure.

Originally published in Pain Management, this article is a summary of a study performed to look at the benefit, if any, of more than one epidural steroid injection in the spine before the mild® Procedure. Minimally invasive lumbar decompression (commonly known as the mild Procedure) and epidural steroid injections are both common treatment options for lumbar spinal stenosis (commonly referred to as LSS), a condition that causes chronic lower back pain in older adults. To determine how to best treat LSS patients, healthcare professionals use a guide to help with the decision-making process (called an algorithm) to pass through non-medical to more invasive therapies that often includes one or more epidural steroid injections. An epidural steroid injection is medication inserted in the lower back to reduce swelling and provide relief from pain. Researchers wanted to look at a change to when in the treatment process the mild Procedure is carried out. In the study, researchers compared the medical records of participants who had received either just one or no steroid injection prior to the mild Procedure, to participants who received two or more epidural steroid injections prior to the mild Procedure. Similar outcomes in both treatment groups in this study proved that giving more than one epidural steroid injection prior to the mild Procedure did not improve how well patients did and may have delayed patient care. Based on the results of the study, it is recommended that the standard treatment process for LSS patients be changed to give the mild Procedure either as soon as LSS is diagnosed or after the failure of the first epidural steroid injection.

Minimally invasive direct decompression for lumbar spinal stenosis: impact of multiple prior epidural steroid injections.

Background: A modified algorithm for the treatment of lumbar spinal stenosis with hypertrophic ligamentum flavum using minimally-invasive lumbar decompression (mild®)was assessed, with a focus on earlier intervention. Patients & methods: Records of 145 patients treated with mild after receiving 0-1 epidural steroid injections (ESIs) or 2+ ESIs were retrospectively reviewed. Pain assessments as measured by visual analog scale (VAS) scores were recorded at baseline and 1-week and 3-month follow-ups. Results: Improvements in VAS scores at follow-ups compared with baseline were significant in both groups. No statistically significant differences were found between the two groups. Conclusion: Multiple ESIs prior to mild showed no benefit. A modified algorithm to perform mild immediately upon diagnosis or after the failure of the first ESI is recommended.

Lay abstract Physicians use a structured decision-making process (an algorithm) to decide how best to treat lumbar spinal stenosis (LSS) that results from abnormal thickening of the spinal ligaments that run the length of the spinal cord. Early treatments can include one or more epidural steroid injections (ESIs). This study evaluated a change to the algorithm that involves earlier intervention with a minimally invasive, short outpatient procedure that removes a major root cause of the abnormal thickening (lumbar decompression) and leaves no implants behind. Records of patients treated with minimally-invasive lumbar decompression (mild^®) after receiving either a single ESI procedure or none at all, were compared with the records of patients who underwent the mild procedure after receiving two or more ESIs (145 total patients). The patients' pain scores before surgery, at 1 week postsurgery and at 3 months postsurgery were reviewed. The improvements in pain scores following the mild procedure were compared within each group and between the two groups. The improvements in pain scores at both the 1-week and 3-month follow-up visits indicated that the mild procedure had a positive effect for both groups. Further, there were no significant differences in how much pain scores improved when the two groups were compared. Since neither group experienced significantly more pain relief than the other, there appears to be no benefit to having multiple ESI procedures before undergoing the mild procedure. The authors recommend that the algorithm be modified to perform the mild procedure either as soon as LSS is diagnosed or after the failure of the first ESI procedure.

A low-temperature external cavity diode laser for broad wavelength tuning.

We report on the design and characterization of a low-temperature external cavity diode laser (ECDL) system for broad wavelength tuning. The performance achieved with multiple diode models addresses the scarcity of commercial red laser diodes below 633 nm, which is a wavelength range relevant to the spectroscopy of many molecules and ions. Using a combination of multiple-stage thermoelectric cooling and water cooling, the operating temperature of a laser diode is lowered to -64 °C, more than 85 °C below the ambient temperature. The laser system integrates temperature and diffraction grating feedback tunability for coarse and fine wavelength adjustments, respectively. For two different diode models, single-mode operation is achieved with 38 mW output power at 616.8 nm and 69 mW at 622.6 nm, more than 15 nm below their ambient temperature free-running wavelengths. The ECDL design can be used for diodes of any available wavelength, allowing individual diodes to be tuned continuously over tens of nanometers and extending the wavelength coverage of commercial laser diodes.

Spinal Cord Stimulation Provides Pain Relief with Improved Psychosocial Function: Results from EMP3OWER.

OBJECTIVE: The EMP3OWER™ study evaluated spinal cord stimulation (SCS) safety and efficacy and the associated changes in psychosocial and functional outcomes. METHODS: Upon informed consent and IRB approval, 620 eligible subjects were enrolled prior to SCS trial evaluation and were assessed at baseline, 3, 6 and 12 months post-implant. Patient-reported pain relief (PRP), numerical rating scale (NRS), satisfaction, quality of life (QOL), and pain disability index (PDI) were assessed at all follow-up visits while the pain catastrophizing scale (PCS), short form-36 (SF-36), short form-McGill pain questionnaire version 2 (SF-MPQ-2), and the state-trait anxiety inventory (STAI) were assessed at the 6- and 12-month follow-up visits. Device and/or procedure-related adverse events were also recorded and reported. Subjects reporting a PRP ≥ 50% were considered responders. Repeated measures analysis of variance (RMANOVA) examined the changes across time for all continuous measures. RESULTS: A total of 401 (71%) subjects received a permanent implant. Mean (±SD) patient-reported pain relief was 59.3% (±26.2), 59.2% (±28.9), and 58.2% (±32.0) at 3, 6, and 12 months, respectively. A majority of enrolled subjects were responders at 3 (75.5%), 6 (74.7%), and 12 months (69.7%). RMANOVA revealed a statistically significant change for NRS, PCS, PDI, SF-36, SF-MPQ-2, and STAI scores. At 3 months, the majority of subjects (85.7%) were either very satisfied or satisfied with their device, with similar results at 6 and 12 months. At 3 months, the majority of subjects (73.3%) reported greatly improved or improved QOL with similar results at 6 and 12 months. CONCLUSIONS: Spinal cord stimulation provided pain relief and significant improvement of patient psychological and functional outcome measures.

Studying Musical and Linguistic Prediction in Comparable Ways: The Melodic Cloze Probability Method.

Prediction or expectancy is thought to play an important role in both music and language processing. However, prediction is currently studied independently in the two domains, limiting research on relations between predictive mechanisms in music and language. One limitation is a difference in how expectancy is quantified. In language, expectancy is typically measured using the cloze probability task, in which listeners are asked to complete a sentence fragment with the first word that comes to mind. In contrast, previous production-based studies of melodic expectancy have asked participants to sing continuations following only one to two notes. We have developed a melodic cloze probability task in which listeners are presented with the beginning of a novel tonal melody (5-9 notes) and are asked to sing the note they expect to come next. Half of the melodies had an underlying harmonic structure designed to constrain expectations for the next note, based on an implied authentic cadence (AC) within the melody. Each such 'authentic cadence' melody was matched to a 'non-cadential' (NC) melody matched in terms of length, rhythm and melodic contour, but differing in implied harmonic structure. Participants showed much greater consistency in the notes sung following AC vs. NC melodies on average. However, significant variation in degree of consistency was observed within both AC and NC melodies. Analysis of individual melodies suggests that pitch prediction in tonal melodies depends on the interplay of local factors just prior to the target note (e.g., local pitch interval patterns) and larger-scale structural relationships (e.g., melodic patterns and implied harmonic structure). We illustrate how the melodic cloze method can be used to test a computational model of melodic expectation. Future uses for the method include exploring the interplay of different factors shaping melodic expectation, and designing experiments that compare the cognitive mechanisms of prediction in music and language.

Increased pain catastrophizing associated with lower pain relief during spinal cord stimulation: results from a large post-market study.

BACKGROUND: Pain catastrophizing is a negative cognitive distortion to actual or anticipated pain. Our aim was to determine if greater catastrophizing has a deleterious relationship with pain intensity and efficacy outcomes in patients receiving SCS. METHODS: As part of an ongoing Institutional Review Board-approved, multi-site, single arm post-market study, 386 patients were implanted with an Eon Mini™ SCS system and had follow-up visits at 3, 6, and 12 months post-implant. Outcomes collected during the study included, but were not limited to pain intensity using the numeric rating scale (NRS), patient reported pain relief (PRP), satisfaction with their SCS system, quality of life (QOL), pain catastrophizing scale (PCS) and state-trait anxiety index (STAI). RESULTS: NRS scores were associated with higher PCS scores at six months (r = 0.50, p < 0.001). The PCS was a strong predictor of the NRS when controlled for known confounders. Patients with PCS ≥30 at 6-months post-implant had a lower six-month PRP (p < 0.001) and were five times more likely to report dissatisfaction with their SCS device (p < 0.001, OR = 5.46, 95% CI: 2.51-6.35). Additionally, at six months, those who were clinically catastrophizing were three times more likely to report deterioration in QOL (p < 0.002, OR = 3.12, 95% CI: 1.62-5.51). These findings were similar at the 12 months follow visit. CONCLUSIONS: Our results indicate that patients with greater catastrophizing, post-implant, were more likely to report higher pain intensity and lower pain relief, quality of life and satisfaction with SCS. These results indicate that associations between pain intensity and pain-related mental health may contribute to influence the overall efficacy of SCS.

Use of a newly developed delivery device for percutaneous introduction of multiple lead configurations for spinal cord stimulation.

OBJECTIVE: The Epiducer lead delivery system is a novel lead delivery device that can be used to percutaneously implant S-Series paddle leads (St. Jude Medical, Plano, TX, USA) as well as multiple percutaneous leads obviating the need for laminectomy and/or multiple needle sticks, respectively. This study evaluates the safety and usage of the Epiducer lead delivery system. METHODS: An Institutional Review Board-approved observational data collection study was conducted to evaluate usage patterns of the Epiducer system. In addition to the number and frequency of different lead configurations, the following procedural aspects of the surgery were recorded during the evaluation: angle of entry, distance from entry to final lead placement, and physician feedback. Descriptive statistics on adverse events, procedural aspects, and patient outcomes were compiled. RESULTS: Data were collected from 163 patients across 25 investigational sites. Physicians successfully implanted patients using the Epiducer during 89% of the procedures. Seven possible lead configurations were implanted. There were 96% and 92% of physicians "satisfied" or "very satisfied" with accessing the epidural space and placing multiple leads with the Epiducer delivery system, respectfully. Eighty-nine percent of physicians were "satisfied" or "very satisfied" with implanting an S-Series paddle lead using the Epiducer delivery system. Ninety-five percent of physicians were "satisfied" or "very satisfied" with the Epiducer delivery system overall. Ten patients (6%) experienced adverse events. CONCLUSION: Results suggest that the Epiducer delivery system allows for the safe and successful percutaneous implantation of paddle leads and/or multiple lead configurations. Furthermore, physicians are satisfied with the Epiducer delivery system.

Episodic migraine and obesity and the influence of age, race, and sex.

OBJECTIVE: To evaluate the episodic migraine (EM)-obesity association and the influence of age, race, and sex on this relationship. METHODS: We examined the EM-obesity association and the influence of age, race, and sex in 3,862 adult participants of both black and white race interviewed in the National Comorbidity Survey Replication. EM diagnostic criteria were based on the International Classification of Headache Disorders. Body mass index was classified as underweight (<18.5 kg/m(2)), normal (18.5-24.9 kg/m(2)), overweight (25-29.9 kg/m(2)), or obese (≥30 kg/m(2)). Adjusted odds ratios (ORs) and 95% confidence intervals (CIs) for EM were estimated using logistic regression. Models were stratified by age (<50/≥50 years), race (white/black), and sex (male/female). RESULTS: A total of 188 participants fulfilled criteria for EM. In all participants, the adjusted odds of EM were 81% greater in individuals who were obese compared with those of normal weight (OR 1.81; 95% CI: 1.27-2.57; p = 0.001), with a significant trend of increasing odds of EM with increasing obesity status from normal weight to overweight to obese (p = 0.001). In addition, stratified analyses demonstrated that the odds of EM were greater in obese as compared with normal-weight individuals who were 1) younger than 50 years of age (OR 1.86; 95% CI: 1.20-2.89; p for trend = 0.008), 2) white (OR 2.06; 95% CI: 1.41-3.01; p for trend ≤0.001), or 3) female (OR 1.95; 95% CI: 1.38-2.76; p for trend ≤0.001). CONCLUSION: The odds of EM are increased in those with obesity, with the strongest relationships among those younger than 50 years, white individuals, and women.

Verrucous cutaneous sarcoidosis: case report and review of this unusual variant of cutaneous sarcoidosis.

Sarcoidosis is a multisystem disorder of unknown origin, characterized by the accumulation of lymphocytes and mononuclear histiocytes inducing the formation of noncaseating "naked" epithelioid granulomas. The lungs, lymphatic system, and skin are most often affected, but sarcoidosis may affect any organ. Cutaneous involvement of sarcoidosis is often the sentinel sign of the disease, with the skin sometimes being exclusively affected. We present a case of a 54-year-old African American woman with long-standing history of pulmonary sarcoidosis that presented with multiple verrucous cutaneous lesions on the upper and lower extremities mimicking carcinoma. The initial cutaneous biopsy was superficial in nature, and the pathologist raised the consideration of a possible keratoacanthoma. A deeper skin shave biopsy was performed, and the histopathology showed verrucous pseudoepitheliomatous epidermal hyperplasia with scattered noncaseating granulomas in the superficial dermis. Stains (acid-fast bacillus, Periodic acid-Schiff, and Gomori-Grocott methenamine silver stains) were negative for microorganisms. Given the clinical setting and histomorphology of the cutaneous lesions, the diagnosis of verrucous sarcoidosis was rendered. Verrucous sarcoidosis is a rare cutaneous manifestation of sarcoidosis that could be easily misdiagnosed if it is not appropriately biopsied. This hinders the precise evaluation of the histological specimen, overall clinical picture, and administration of appropriate therapy.

Differentiation of transverse sinus thrombosis from congenitally atretic cerebral transverse sinus with CT.

BACKGROUND AND PURPOSE: Transverse sinus thrombosis can have nonspecific clinical and radiographic signs. We hypothesized that the novel "sigmoid notch sign" (on head CT) can help differentiate transverse sinus thrombosis from a congenitally atretic sinus among individuals with absent signal in 1 transverse sinus by MR venography. METHODS: We retrospectively evaluated 53 subjects with a unilaterally absent transverse sinus signal on MR venography. Eleven had true transverse sinus thrombosis and 42 had an atretic transverse sinus. Reviewers were trained in the sigmoid notch sign: "positive" if 1 of the sigmoid notches was asymmetrically smaller than the other, consistent with a congenitally absent transverse sinus on that side. This sign was scored on CT scans by 2 blinded reviewers to determine if signal dropout was clot or atretic sinus. A consensus rating was reached when the reviewers disagreed. Characteristics of the sigmoid notch sign as a diagnostic test were compared with a gold standard of full chart review by an independent reviewer. RESULTS: Each reviewer had a sensitivity of 91% (detecting 10 of 11 clots based on a negative sigmoid notch sign) and specificity of 71% to 81%; consensus specificity increased to 86% (36 of 42 individuals with an atretic sinus had a positive notch sign, detecting atretic sinuses based on presence of the sign). CONCLUSIONS: Asymmetries of the sigmoid notches on noncontrast brain CT is a very sensitive and specific measure of differentiating transverse sinus thrombosis from an atretic transverse sinus when absence of transverse sinus flow is visualized on MR venography.

Occipital nerve pulsed radiofrequency treatment: a multi-center study evaluating predictors of outcome.

OBJECTIVE: Occipital neuralgia (ON) is a challenging condition for which there is no reference standard for treatment. The purpose of this study was to provide outcome data on the largest study to date evaluating pulsed radiofrequency (PRF) for ON and to determine whether any demographic, clinical, or treatment characteristics are associated with success. DESIGN: Retrospective data analysis was conducted in 102 subjects evaluating the effect of myriad factors on treatment success. SETTING: This study was conducted in academic civilian and military pain treatment centers. PATIENTS: One hundred and two consecutive patients with a primary diagnosis of ON were treated with PRF of the greater and/or lesser occipital nerve. OUTCOME MEASURES: A positive primary outcome was predefined as ≥50% pain relief lasting at least 3 months. The secondary outcome measure was procedural satisfaction. RESULTS: Fifty-two (51%) patients experienced ≥50% pain relief and satisfaction with treatment lasting at least 3 months. Variables associated with a positive outcome included a traumatic inciting event (65.7% success rate; P=0.03), lower diagnostic block volumes (odds ratio [OR]: 0.72; 95% confidence interval [CI]: 0.62-0.82; P<0.0001), and employment of multiple rounds of PRF (OR: 2.95; 95% CI: 1.77-4.92; P<0.0001). Factors correlating with treatment failure included extension of pain anterior to the scalp apex (OR: 0.32; 95% CI: 0.14-0.73; P=0.006) and ongoing secondary gain issues (OR: 0.19; 95% CI: 0.11-0.33; P<0.0001). CONCLUSION: PRF may provide intermediate-term benefit in ON to a significant proportion of refractory cases. Careful attention to selection criteria and treatment parameters may further improve treatment outcomes.

Dr. Harvey Cushing's attempts to cure migraine based on theories of pathophysiology.

A multitude of theories characterized medical thought on migraine in the early 20th century. Newly discovered historical case files revealed Dr. Harvey Cushing's previously unpublished early attempts at surgical cure of migraine. Following institutional review board approval, and through the courtesy of the Alan Mason Chesney Archives, the authors reviewed the microfilm surgical records for The Johns Hopkins Hospital from 1896 to 1912. Patients undergoing surgical intervention by Dr. Harvey Cushing for the treatment of migraine were selected for further review. All 4 patients in the series were women and ranged in age from 29 to 41 years old. The women were admitted and observed in the hospital until a migraine occurred. Surgeries were performed while the women were in the midst of an attack. Cushing used surgical strategies including decompression, temporal artery ligation, and removal of the spine of the second vertebra. In each case, the patients' headaches eventually returned following surgery. Cushing relied on a combination of contemporary theories on migraine including humeral science, vasospastic theory, organic cause, and increased intracranial pressure. His unpublished efforts foreshadowed future surgical efforts at curing migraines.

Sex-related differences in epidemiological and clinic-based headache studies.

This manuscript discusses sex-related differences in headache prevalence, the symptoms and natural history of migraine, associated disability, and co-morbid disorders. The role of sex hormones is discussed with reference to the effects of hormonal events across the reproductive years and the specific effects of the menstrual cycle on migraine. Differences between the sexes were identified across all parameters reviewed. Future research should ensure that data are analyzed separately for men and women to ensure that differences between the sexes are identified.

Making psycholinguistics musical: self-paced reading time evidence for shared processing of linguistic and musical syntax.

Linguistic processing, especially syntactic processing, is often considered a hallmark of human cognition; thus, the domain specificity or domain generality of syntactic processing has attracted considerable debate. The present experiments address this issue by simultaneously manipulating syntactic processing demands in language and music. Participants performed self-paced reading of garden path sentences, in which structurally unexpected words cause temporary syntactic processing difficulty. A musical chord accompanied each sentence segment, with the resulting sequence forming a coherent chord progression. When structurally unexpected words were paired with harmonically unexpected chords, participants showed substantially enhanced garden path effects. No such interaction was observed when the critical words violated semantic expectancy or when the critical chords violated timbral expectancy. These results support a prediction of the shared syntactic integration resource hypothesis (Patel, 2003), which suggests that music and language draw on a common pool of limited processing resources for integrating incoming elements into syntactic structures. Notations of the stimuli from this study may be downloaded from pbr.psychonomic-journals.org/content/supplemental.

Monitoring buried free flaps: limitations of the implantable Doppler and use of color duplex sonography as a confirmatory test.

BACKGROUND: Postoperative monitoring of free flaps is important to minimize the risk of flap failure, but monitoring buried free flaps is difficult because the standard methods of clinical examination and surface Doppler monitoring are not possible. Buried free flaps are often monitored using an implantable 20-MHz ultrasonic Doppler probe. METHODS: The authors conducted a retrospective clinical study of buried free flaps to assess the reliability of the implantable Doppler probe in postoperative monitoring of free flaps. RESULTS: During the 38-month study period, 956 free flap operations were performed at the authors' institution. Twenty (2.1 percent) of these cases involved completely buried free flaps in which an implantable Doppler probe was used for flap monitoring. Implantable Doppler probe monitoring had a 100 percent sensitivity rate in detecting loss of flap perfusion, making it a good screening test for free flap viability. However, it suffered from a high false-positive rate of 88 percent, which resulted in a high proportion of subsequent negative surgical explorations. In one case, color duplex sonography, a rapid and noninvasive test, revealed that the loss of signal from the implantable Doppler probe was a false-positive result. CONCLUSIONS: The implantable Doppler probe is a sensitive method for postoperative monitoring of free flaps but is prone to false-positive signals. The use of color duplex sonography to confirm implantable Doppler probe findings may avert unnecessary surgical exploration, thereby improving postoperative monitoring of free flaps.

Comparing the rhythm and melody of speech and music: the case of British English and French.

For over half a century, musicologists and linguists have suggested that the prosody of a culture's native language is reflected in the rhythms and melodies of its instrumental music. Testing this idea requires quantitative methods for comparing musical and spoken rhythm and melody. This study applies such methods to the speech and music of England and France. The results reveal that music reflects patterns of durational contrast between successive vowels in spoken sentences, as well as patterns of pitch interval variability in speech. The methods presented here are suitable for studying speech-music relations in a broad range of cultures.