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1.
Phys Rev Lett ; 131(8): 082502, 2023 Aug 25.
Article in English | MEDLINE | ID: mdl-37683153

ABSTRACT

We present an apparatus for detection of cyclotron radiation yielding a frequency-based ß^{±} kinetic energy determination in the 5 keV to 2.1 MeV range, characteristic of nuclear ß decays. The cyclotron frequency of the radiating ß particles in a magnetic field is used to determine the ß energy precisely. Our work establishes the foundation to apply the cyclotron radiation emission spectroscopy (CRES) technique, developed by the Project 8 Collaboration, far beyond the 18-keV tritium endpoint region. We report initial measurements of ß^{-}'s from ^{6}He and ß^{+}'s from ^{19}Ne decays to demonstrate the broadband response of our detection system and assess potential systematic uncertainties for ß spectroscopy over the full (MeV) energy range. To our knowledge, this is the first direct observation of cyclotron radiation from individual highly relativistic ß's in a waveguide. This work establishes the application of CRES to a variety of nuclei, opening its reach to searches for new physics beyond the TeV scale via precision ß-decay measurements.

2.
Phys Rev Lett ; 129(18): 182502, 2022 Oct 28.
Article in English | MEDLINE | ID: mdl-36374704

ABSTRACT

We report the first precise measurement of a ß-recoil correlation from a radioactive noble gas (^{6}He) confined via a magneto-optical trap. The measurement is motivated by the search for exotic tensor-type contributions to the charged weak current. Interpreted as tensor currents with right-handed neutrinos, the measurements yield |C_{T}/C_{A}|^{2}≤0.022 (90% confidence limit, C.L.). On the other hand, for left-handed neutrinos the limits are 0.007

3.
J Pediatr Urol ; 15(5): 528.e1-528.e8, 2019 Oct.
Article in English | MEDLINE | ID: mdl-31445857

ABSTRACT

INTRODUCTION: Pediatric bladder and bowel dysfunction (BBD) is a common problem in children. However, the current ability to diagnosis and quantify pediatric BBD is limited as only a few validated instruments exist. In addition, the current questionnaires are limited by their lack of psychometric processing and methods of validation. To address these issues, the authors developed a new questionnaire to objectively diagnose pediatric BBD symptoms. This study aimed to evaluate the performance of this newly devised objective instrument in diagnosing and quantifying the symptomatology of BBD in children. MATERIALS AND METHODS: An 18-item, 5-point questionnaire was developed using both a literature review and expert opinions. The total questionnaire score could range from 0 to 72. Questions were subgrouped into six symptom categories: (1) nocturnal enuresis, (2) lower urinary tract symptoms, (3) urinary holding, (4) infrequent urination, (5) bowel symptoms, and (6) daytime urinary incontinence. The questionnaire also assessed the degree of bother associated with the symptoms. Patients were divided into cases and controls, and these two groups were compared. DISCUSSION/RESULTS: A total of 1265 new patients (758 cases and 507 controls) completed the new BBD questionnaire. The mean age of the whole study cohort was 9.5 years (range, 3-19 years). The total mean questionnaire score was significantly higher at 23 (3-58) in the cases, compared with 8 (0-35) in the controls (p < 0.001) (Summary Figure). Reliability analysis of the 18-item instrument showed a Cronbach's alpha reliability coefficient of 0.80 for the scale. CONCLUSIONS: This new instrument provides a valid and reliable method for diagnosis of pediatric BBD and classification of patients into subcategories of BBD based on their specific symptoms.


Subject(s)
Constipation/diagnosis , Enuresis/diagnosis , Mass Screening/methods , Psychometrics/methods , Surveys and Questionnaires , Urinary Incontinence/diagnosis , Adolescent , Child , Child, Preschool , Constipation/epidemiology , Enuresis/epidemiology , Female , Follow-Up Studies , Humans , Male , Morbidity/trends , Reproducibility of Results , Retrospective Studies , United States/epidemiology , Urinary Incontinence/epidemiology , Young Adult
4.
J Pediatr Urol ; 13(4): 391.e1-391.e6, 2017 Aug.
Article in English | MEDLINE | ID: mdl-28729177

ABSTRACT

INTRODUCTION: Bladder and bowel dysfunction (BBD) are common problems in children presenting for pediatric urology referral. Psychiatric issues may be present in these children, making their treatment difficult. In 2013, the University of Iowa Voiding Improvement Partnership (VIP) Clinic was established for the treatment of these patients. STUDY OBJECTIVE: This study sought to evaluate early experience with this specialized clinic, to determine the pre-existing urologic and psychologic conditions seen in these clinic patients, and to evaluate the clinical outcomes after VIP treatment. STUDY DESIGN: A retrospective, Institutional Review Board-approved review of all patients seen in the VIP Clinic was performed. The following were evaluated: patient demographics, underlying urologic and psychologic diagnosis, and treatment decisions. All patients were asked to complete the University of Iowa Pediatric Bladder and Bowel Dysfunction questionnaire at each visit. Questionnaire scores from the patients' first and most recent clinic visits were compared. RESULTS: To date, 66 patients have been evaluated at the VIP Clinic, accounting for 112 clinic visits. The mean age of the VIP patients was 8.5 years (range, 4-16) and 59% of the patients were female. Pre-existing urological conditions and psychological conditions are shown in the Summary Table. A large number (62%) of patients required further psychological evaluation, secondary to concern for an undiagnosed psychiatric issue. In addition, the clinic had improved patients' BBD symptoms over time. When first evaluated in clinic, patients had an average Iowa BBD Questionnaire score of 31 (range, 47-13), which improved to an average score of 25 (range, 47-7) (P = 0.03). In addition, 23% of the patients improved to where they could be discharged from uro-psychologic care. CONCLUSIONS: It was feasible to establish the present multidisciplinary uro-psychology clinic. Such a clinic may unearth undiagnosed psychological issues, and improve bowel and bladder dysfunction in these difficult-to-treat patients.


Subject(s)
Constipation/therapy , Mental Disorders/diagnosis , Urination Disorders/therapy , Adolescent , Ambulatory Care Facilities , Child , Child, Preschool , Constipation/etiology , Constipation/psychology , Female , Humans , Male , Mental Disorders/complications , Mental Disorders/therapy , Retrospective Studies , Treatment Outcome , Urination Disorders/etiology , Urination Disorders/psychology
5.
J Pediatr Urol ; 13(2): 207.e1-207.e5, 2017 Apr.
Article in English | MEDLINE | ID: mdl-28089295

ABSTRACT

INTRODUCTION AND OBJECTIVE: Management of vesicoureteral reflux (VUR) remains controversial, and reflux grade constitutes an important prognostic factor. Recent work has suggested that distal ureteral diameter ratio (UDR) is a predictive factor relative to clinical outcome independent of grade. Previous studies have noted significant inter-rater variability with grading of VUR. The present study compared inter-rater reliability of reflux grade and UDR in children with primary VUR. STUDY DESIGN: Four pediatric urologists independently reviewed, in a blinded fashion, voiding cystourethrograms. For each renal unit, grade was assigned according to the standardized international scale. The UDR was calculated by dividing the largest ureteral diameter within the false pelvis by the distance between L1-L3 vertebral bodies. Correlation within each rater was determined using Pearson's correlation coefficient. Reliability of VUR grade and UDR were calculated using two-way ANOVA model inter-rater agreement. RESULTS: Four independent raters reliably measured VUR grade (ICC = 0.87, 95% CI = 0.78-0.93) and UDR (ICC = 0.95, 95% CI = 0.92-0.97). While UDR and grade were equally reliable measures, UDR had a tighter confidence interval. For each rater, grade and UDR were well correlated (r = 0.73-0.84; P < 0.0001). For higher-grade reflux, grade was more variable than UDR (Summary Figure). Using empirical thresholds, the increased variability of grade compared with UDR may lead to significant differences in clinical decision-making among physicians (P = 0.022). DISCUSSION: Known discordance with grading reflux emphasizes the need for a more objective VUR measurement, as clinicians and parents often opt for clinical intervention based on both clinical course and the likelihood of spontaneous resolution. While ICC for UDR and grade were not significantly different, the confidence intervals for grade were wider due to greater variability among grade measurements. This suggests that using UDR measurements may lead to more accurate characterization of VUR and ultimately more consistent clinical decision-making across providers. CONCLUSIONS: Ureteral diameter ratio has good inter-rater reliability among pediatric urologists, with less clinically relevant variability than VUR grade. Ureteral diameter ratio is a more objective and reliable measure than grade, and may be more useful in clinical decision-making.


Subject(s)
Cystography/methods , Ureter/diagnostic imaging , Vesico-Ureteral Reflux/diagnostic imaging , Child , Child, Preschool , Databases, Factual , Female , Humans , Infant , Male , Observer Variation , Predictive Value of Tests , Prognosis , Retrospective Studies , Risk Assessment , Severity of Illness Index , Ureter/physiopathology , Ureteroscopy/methods , Vesico-Ureteral Reflux/physiopathology , Vesico-Ureteral Reflux/surgery
6.
J Pediatr Urol ; 11(4): 183.e1-6, 2015 Aug.
Article in English | MEDLINE | ID: mdl-26189589

ABSTRACT

INTRODUCTION: For children with VUR the grade of vesicoureteral reflux (VUR) remains one of the most predictive factors relative to outcome. However, the subjective nature of the currently accepted international reflux grading system (IRGS) leads to inter-observer variation. The potential of a direct measurement of the distal ureter on the voiding cystourethrogram (VCUG) normalized to the L1-L3 vertebral body distance (ureteral diameter ratio - UDR) to augment the ability of IRGS to predict the ultimate clinical outcome has previously been reported in a group of 79 children. OBJECTIVE: The goal of this current review was to expand the previous review and analysis in order to assess the predictive ability of the UDR with respect to earlier clinical outcome and to compare this ability to the grade of VUR while controlling for other variables. STUDY DESIGN: This retrospective review of the VCUG of 157 children with primary VUR included 124 girls and 33 boys with a mean age of 2.7 years (7 days-13.5 years). In addition to the UDR, other variables that were analyzed included: age, gender, VUR grade, laterality, history of febrile urinary tract infection (UTI) or multiple UTIs prior to diagnosis, and bladder-bowel dysfunction (BBD). Cox regression analysis was utilized and a generalized logit model for 2-year outcome was also fitted to compare the effect of UDR and VUR grade using Wald Chi-squared analysis. RESULTS: The 2-year outcome after the VCUG was defined as: persistent VUR (47%), spontaneous VUR resolution (15%), or operative intervention (38%). Reasons for operative intervention included: breakthrough UTI (1/3), decreased relative renal function associated with renal scarring (1/3), and failure to resolve, along with parental preference (1/3). Increasing UDR was significantly associated with increased grade and a decreased chance of spontaneous resolution. It was unlikely for a child with Grade 4, 3, or 2 VUR to have spontaneous resolution if their UDR was above 0.25, 0.3, or 0.35, respectively. In addition, higher grades of VUR, older age, and bilateral VUR were significantly associated with failure to spontaneously resolve VUR. As seen in Figure, children with grades 2 and 3 VUR less than 2 years of age had a better chance of spontaneous resolution with a larger UDR than children 2 years of age or older. When adjusting for age, grade, laterality and multiple UTIs as covariates, each unit increase of UDR of 0.1 was significantly associated with either persistent VUR (OR = 1.73, 95% CI = 1.02-2.95, P = 0.043) or the need for surgical intervention (OR = 2.40, 95% CI = 1.39-4.17, P = 0.002) compared to spontaneous resolution. When testing the effect of UDR and grade of reflux in the same model, UDR was noted to have a larger effect on predicting failure to spontaneously resolve VUR than grade (Wald Chi-Squared 13.6; P = 0.001 vs 3.62; P = 0.46, respectively). DISCUSSION: The UDR is a readily available objective measurement on the VCUG that has demonstrated ability to enhance the International Reflux Grading System. Limitations of the current review include operative intervention in 12% of the children for failure to improve or resolve VUR. This surgical intervention inhibits determination of spontaneous resolution rates. The findings in this study reflect those in a series of children from a single institution and, therefore, may be impacted by clinical practice bias and geographic variations. Subsequent multi-institutional studies could further define the potential of UDR as either an independent or additive predictive factor for grading VUR that will further permit individualized patient management. CONCLUSION: In this single institution series, UDR was highly correlated with VUR grade; however, UDR proved more predictive of spontaneous resolution, persistence, or operative intervention than grade.


Subject(s)
Ureter/diagnostic imaging , Urography/methods , Vesico-Ureteral Reflux/diagnostic imaging , Adolescent , Child , Child, Preschool , Female , Follow-Up Studies , Humans , Infant , Infant, Newborn , Male , Retrospective Studies , Severity of Illness Index , Time Factors
7.
Infection ; 42(2): 433-6, 2014 Apr.
Article in English | MEDLINE | ID: mdl-24272915

ABSTRACT

Acute focal bacterial nephritis (AFBN) is a rare, acute focal infection of the renal parenchyma without liquefaction. The pathogenesis is thought to be due to hematogenous infection or ascending infection from the lower urinary tract. Escherichia coli has been the major pathogen isolated in prior cases, but other Gram-negative enteric pathogens and Staphylococcus aureus have been reported as well. It is well described in children and adults with diabetes and organ transplantation, but has not been previously reported in healthy adults. We report a case of an immunocompetent adult female who presented with a methicillin-resistant Staphylococcus aureus bacteremia after a skin and soft tissue infection that resulted in AFBN.


Subject(s)
Anti-Bacterial Agents/therapeutic use , Daptomycin/therapeutic use , Nephritis/drug therapy , Staphylococcal Infections/drug therapy , Acute Disease , Adult , Anti-Bacterial Agents/pharmacology , Daptomycin/pharmacology , Female , Humans , Methicillin-Resistant Staphylococcus aureus/drug effects , Methicillin-Resistant Staphylococcus aureus/isolation & purification , Nephritis/microbiology , Nephritis/pathology , Skin Diseases, Bacterial/complications , Skin Diseases, Bacterial/drug therapy , Skin Diseases, Bacterial/pathology , Soft Tissue Infections/complications , Soft Tissue Infections/drug therapy , Soft Tissue Infections/pathology , Staphylococcal Infections/microbiology , Staphylococcal Infections/pathology , Treatment Outcome
8.
Phys Rev Lett ; 105(15): 152501, 2010 Oct 08.
Article in English | MEDLINE | ID: mdl-21230896

ABSTRACT

The radionuclide 22Na is a potential astronomical observable that is expected to be produced in classical novae in quantities that depend on the thermonuclear rate of the 22Na(p,γ)23Mg reaction. We have measured the strengths of low-energy 22Na(p,γ)23Mg resonances directly and absolutely using a radioactive 22Na target. We find the strengths of resonances at Ep=213, 288, 454, and 610 keV to be higher than previous measurements by factors of 2.4-3.2, and we exclude important contributions to the rate from proposed resonances at Ep=198, 209, and 232 keV. The 22Na abundances expected in the ejecta of classical novae are reduced by a factor of ≈2.

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