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1.
Nature ; 601(7894): 531-536, 2022 01.
Article in English | MEDLINE | ID: mdl-34847568

ABSTRACT

Quantum many-body systems display rich phase structure in their low-temperature equilibrium states1. However, much of nature is not in thermal equilibrium. Remarkably, it was recently predicted that out-of-equilibrium systems can exhibit novel dynamical phases2-8 that may otherwise be forbidden by equilibrium thermodynamics, a paradigmatic example being the discrete time crystal (DTC)7,9-15. Concretely, dynamical phases can be defined in periodically driven many-body-localized (MBL) systems via the concept of eigenstate order7,16,17. In eigenstate-ordered MBL phases, the entire many-body spectrum exhibits quantum correlations and long-range order, with characteristic signatures in late-time dynamics from all initial states. It is, however, challenging to experimentally distinguish such stable phases from transient phenomena, or from regimes in which the dynamics of a few select states can mask typical behaviour. Here we implement tunable controlled-phase (CPHASE) gates on an array of superconducting qubits to experimentally observe an MBL-DTC and demonstrate its characteristic spatiotemporal response for generic initial states7,9,10. Our work employs a time-reversal protocol to quantify the impact of external decoherence, and leverages quantum typicality to circumvent the exponential cost of densely sampling the eigenspectrum. Furthermore, we locate the phase transition out of the DTC with an experimental finite-size analysis. These results establish a scalable approach to studying non-equilibrium phases of matter on quantum processors.


Subject(s)
Cold Temperature , Phase Transition , Thermodynamics
3.
Female Pelvic Med Reconstr Surg ; 26(2): 101-106, 2020 02.
Article in English | MEDLINE | ID: mdl-31990796

ABSTRACT

OBJECTIVE: To evaluate the prevalence and severity of urinary incontinence (UI) in women who participate in CrossFit classes compared with women who participate in non-CrossFit group fitness classes. METHODS: The authors conducted a cross-sectional study of women who participate in either CrossFit or non-CrossFit group fitness classes using an online survey. Participants provided demographic information and completed the Incontinence Severity Index and Urinary Distress Inventory. Participants were recruited from local CrossFit and non-CrossFit gyms, online via social media, and an electronic CrossFit Newsletter. Associated comorbidities, exercises associated with UI, and coping mechanisms for urinary leakage were also assessed. RESULTS: Four hundred twenty-three women meeting inclusion criteria completed the survey, including 322 CrossFit participants and 101 non-CrossFit participants. We found that CrossFit participants were older than non-CrossFit participants and more likely to self-identify as non-Hispanic white. CrossFit participants more commonly reported UI (84% vs 48%, P = <0.001), higher severity of UI (Urinary Distress Inventory score: 20.8 vs 12.5, P < 0.001), and specifically more stress UI (73% vs 47%, P < 0.001). Weightlifting and jumping movements were the most common exercises associated with UI in CrossFit participants. Age and participation in CrossFit are significant and independent predictors of UI. CONCLUSIONS: More than 80% of CrossFit participants reported UI and half of these reported moderate-severe UI, as compared with women who participate in non-CrossFit classes, less than half of whom reported UI with a small minority reporting moderate-severe UI. Exercises most associated with UI were jumping and weightlifting.


Subject(s)
High-Intensity Interval Training , Quality of Life , Urinary Incontinence, Stress , Adaptation, Psychological , Adult , Age Factors , Comorbidity , Cross-Sectional Studies , Female , Fitness Centers/statistics & numerical data , High-Intensity Interval Training/adverse effects , High-Intensity Interval Training/methods , Humans , Physical Fitness/physiology , Prevalence , Risk Factors , Severity of Illness Index , Urinary Incontinence, Stress/diagnosis , Urinary Incontinence, Stress/epidemiology , Urinary Incontinence, Stress/etiology , Urinary Incontinence, Stress/psychology
4.
Compr Psychiatry ; 94: 152123, 2019 10.
Article in English | MEDLINE | ID: mdl-31518848

ABSTRACT

BACKGROUND: This study addresses the strength of associations between trichotillomania (TTM) and other DSM-IV Axis I conditions in a large sample (n = 2606) enriched for familial obsessive-compulsive disorder (OCD), to inform TTM classification. METHODS: We identified participants with TTM in the Johns Hopkins OCD Family Study (153 families) and the OCD Collaborative Genetics Study, a six-site genetic linkage study of OCD (487 families). We used logistic regression (with generalized estimating equations) to assess the strength of associations between TTM and other DSM-IV disorders. RESULTS: TTM had excess comorbidity with a number of conditions from different DSM-IV chapters, including tic disorders, alcohol dependence, mood disorders, anxiety disorders, impulse-control disorders, and bulimia nervosa. However, association strengths (odds ratios) were highest for kleptomania (6.6), pyromania (5.8), OCD (5.6), skin picking disorder (4.4), bulimia nervosa (3.5), and pathological nail biting (3.4). CONCLUSIONS: TTM is comorbid with a number of psychiatric conditions besides OCD, and it is strongly associated with other conditions involving impaired impulse control. Though DSM-5 includes TTM as an OCD-related disorder, its comorbidity pattern also emphasizes the impulsive, appetitive aspects of this condition that may be relevant to classification.


Subject(s)
Disruptive, Impulse Control, and Conduct Disorders/epidemiology , Obsessive-Compulsive Disorder/epidemiology , Trichotillomania/epidemiology , Adult , Comorbidity , Diagnostic and Statistical Manual of Mental Disorders , Disruptive, Impulse Control, and Conduct Disorders/genetics , Female , Genetic Linkage , Humans , Male , Middle Aged , Obsessive-Compulsive Disorder/genetics , Trichotillomania/genetics , Young Adult
5.
Female Pelvic Med Reconstr Surg ; 25(4): 328-335, 2019.
Article in English | MEDLINE | ID: mdl-29489554

ABSTRACT

OBJECTIVE: The aim of this study was to identify smartphone Kegel and pelvic floor exercise applications (apps) and identify those with superior functionality, features, and accuracy. METHODS: We identified a complete list of Kegel and pelvic floor exercise applications by searching iTunes and Google Play stores for "pelvic floor," "pelvic floor exercises," "Kegel," and "Kegel exercises." We used a modified APPLICATIONS scoring system to evaluate all identified apps. RESULTS: We identified 120 apps related to Kegel exercises. Apps unrelated to the pelvic floor, unavailable in English, or duplicated on a separate platform were excluded from the analysis, leaving 90 unique apps. After a preliminary review, we excluded an additional 58 apps that were nonfunctional, required a biofeedback device, or intended for pregnant women. The final 32 apps included 15 paid and 17 free apps. Paid apps had higher rates of privacy features than free apps (80% vs 53%), used more images and figures (53% vs 41%), and were more likely to cite primary literature in their descriptions (33% vs 29%). Paid apps were also more likely to have tech support available (73% vs 53%). Overall score, however, was almost identical between the groups, with paid apps averaging 9.93 and free apps 9.41. The highest rated free and paid app both received a score of 12, consisting of Kegel Trainer and Kegel Trainer Pro, respectively. CONCLUSION: The quality of the apps is markedly variable in both the paid and unpaid applications. Using the APPLICATIONS scoring system, the apps were very similar in overall quality and value.


Subject(s)
Exercise Therapy/methods , Mobile Applications/standards , Pelvic Floor , Female , Humans , Mobile Applications/economics , Smartphone
7.
J Pediatr Adolesc Gynecol ; 30(4): 511-512, 2017 Aug.
Article in English | MEDLINE | ID: mdl-27919713

ABSTRACT

BACKGROUND: Ovarian mature cystic teratomas (MCTs) rarely transform to primary primitive neuroectodermal tumors. This case report offers evidence that MCTs might have undetected microfoci of malignant neural tumors. CASE: We describe the case of a 12-year-old girl who presented with right-sided abdominal pain and distention. Intraoperative findings revealed a right ovarian MCT. However, pathology showed a 0.5-cm focus of malignant neural tumor within the 11-cm MCT. SUMMARY AND CONCLUSION: This patient will need close follow-up with a multidisciplinary team because the clinical implications of this transformation has yet to be defined.


Subject(s)
Neoplasms, Germ Cell and Embryonal/pathology , Neuroectodermal Tumors, Primitive/pathology , Ovarian Neoplasms/pathology , Teratoma/pathology , Child , Female , Humans , Neoplasms, Germ Cell and Embryonal/surgery , Neuroectodermal Tumors, Primitive/surgery , Ovarian Neoplasms/surgery , Teratoma/surgery
8.
Pediatr Neurol ; 43(2): 117-21, 2010 Aug.
Article in English | MEDLINE | ID: mdl-20610122

ABSTRACT

Levetiracetam may be effective in children with acute seizures or status epilepticus. We performed a retrospective chart review of children who received intravenous levetiracetam within 30 minutes of a seizure. Seventy-three patients during a 2-year study period met our inclusion criteria. The mean (+/- S.D.) age and weight of the patients were 5.59 +/- 5.6 years (range, 1 day to 17.8 years) and 23.1 +/- 21 kg (range, 1.97-97 kg), respectively. Patients received a mean (+/- S.D.) levetiracetam dose of 29.4 +/- 13.5 mg/kg. Most children (n = 49, or 67%) received additional antiepileptic drugs to abort their seizure. Overall, the mean (+/- S.D.) total (abortive plus chronic) number of concomitant antiepileptic drugs used by the population was 2.53 +/- 1.7 (1.07 +/- 0.98 as additional abortive therapy, and 1.42 +/- 1.29 as chronic therapy). Most patients received levetiracetam for serial seizures (79%), whereas 12% and 8% manifested a single seizure or status epilepticus, respectively. Clinical effectiveness at 1, 12, 24, 48, and 72 hours after the initial levetiracetam dose constituted the primary study outcome. Eighty-nine percent of patients remained seizure-free at 1 hour. This rate decreased at each evaluation time point. Most patients (71%) were placed on maintenance levetiracetam within 24 hours of their loading dose. The predictive ability of patient and drug regimen variables in outcomes was poor. Only the number of concomitant antiepileptic drugs consistently predicted outcomes. Levetiracetam was well tolerated at the doses studied, and appears most effective in single seizure events.


Subject(s)
Anticonvulsants/therapeutic use , Piracetam/analogs & derivatives , Seizures/drug therapy , Acute Disease , Adolescent , Child , Child, Preschool , Female , Humans , Infant , Infant, Newborn , Injections, Intravenous/methods , Levetiracetam , Male , Piracetam/therapeutic use , Retrospective Studies , Time Factors , Treatment Outcome
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