Quantum Backaction on kg-Scale Mirrors: Observation of Radiation Pressure Noise in the Advanced Virgo Detector.

The quantum radiation pressure and the quantum shot noise in laser-interferometric gravitational wave detectors constitute a macroscopic manifestation of the Heisenberg inequality. If quantum shot noise can be easily observed, the observation of quantum radiation pressure noise has been elusive, so far, due to the technical noise competing with quantum effects. Here, we discuss the evidence of quantum radiation pressure noise in the Advanced Virgo gravitational wave detector. In our experiment, we inject squeezed vacuum states of light into the interferometer in order to manipulate the quantum backaction on the 42 kg mirrors and observe the corresponding quantum noise driven displacement at frequencies between 30 and 70 Hz. The experimental data, obtained in various interferometer configurations, is tested against the Advanced Virgo detector quantum noise model which confirmed the measured magnitude of quantum radiation pressure noise.

Increasing the Astrophysical Reach of the Advanced Virgo Detector via the Application of Squeezed Vacuum States of Light.

Current interferometric gravitational-wave detectors are limited by quantum noise over a wide range of their measurement bandwidth. One method to overcome the quantum limit is the injection of squeezed vacuum states of light into the interferometer's dark port. Here, we report on the successful application of this quantum technology to improve the shot noise limited sensitivity of the Advanced Virgo gravitational-wave detector. A sensitivity enhancement of up to 3.2±0.1 dB beyond the shot noise limit is achieved. This nonclassical improvement corresponds to a 5%-8% increase of the binary neutron star horizon. The squeezing injection was fully automated and over the first 5 months of the third joint LIGO-Virgo observation run O3 squeezing was applied for more than 99% of the science time. During this period several gravitational-wave candidates have been recorded.

Vesicoureteric reflux (VUR) in children: where are we now?

In 1960 Hodson and Edwards published their landmark paper about the association between chronic pyelonefritis and vesicoureteric reflux (VUR). Since then, the approach for VUR became more important (1). In the last 30 years there have been multiple publications on vesicoureteric reflux (VUR) and discussions at Pediatric Urology meetings with the purpose to give answers to the questions what the best treatment is for VUR, at what age the treatment is advocated, does it prevent for febrile urinary tract infections (UTI's) and does it stop of decreases the risk for reflux nefropathy and renal scars Well known are the International Reflux Study (1981) with a European and an American arm in which the researchers compared medical approaches with surgical approaches to reflux, and the Birmingham Reflux study (1987) which was a prospective trial of operative versus non-operative treatment of severe vesicoureteric reflux in children with five years observation (2). In 2009 the group from John Hopkins (Baltimore, USA) published their interim results from a randomized placebo-controlled study of children with VUR (the RIVUR Study) (3). The most recent randomized controlled trial (RCT) is the Swedish Reflux Trial published in the Journal of Urology 2010, July. This was set up as a RCT to compare 3 treatment alternatives, including antibiotic prophylaxis, endoscopic therapy and surveillance as the control group, in regard to recurrent febrile UTIs, renal damage and VUR status after 2 years (4). Since these new data are available, we want to give an update in this specific and interesting field in Pediatric Urology.

Testicular torsion after pediatric kidney transplantation.

Kidney transplantation has become the treatment of choice for children with end-stage renal disease and offers recipients an excellent quality of life. Following kidney transplantation several types of medical and surgical complications can arise. In this report, a testicular torsion occurring on the sixth day after pediatric kidney transplantation is described. It remains unclear whether this unusual complication should be regarded as coincidental or as a direct consequence of the transplantation.

Spinal anesthesia in children: most pediatric urologists are not on board.

OBJECTIVE: In 2016, the Food and Drug Administration issued a warning on general anesthetic medications used for lengthy procedures (>3 h) in children younger than 3 years. Spinal anesthesia can be a safe alternative to general anesthesia for many pediatric urology procedures. It can shorten total operating room (OR) time, provide excellent pain control, and allow parents to reunite with their child immediately after surgery. However, use of spinal anesthesia can also directly affect the operating surgeon (awake patient, time constraints of spinal, and prolonged preoperative time). Members of the Societies for Pediatric Urology (SPU) and European Society of Pediatric Urology (ESPU) were surveyed to get their opinions on the use of spinal anesthesia for routine pediatric urology procedures. It was hypothesized that half of pediatric urologists would favor spinal anesthesia and that SPU members would be more likely to favor spinal anesthesia than their European colleagues. MATERIALS AND METHODS: A short survey with five clinical scenarios was created. Scenarios assessed physicians' recommendations regarding timing and the type of anesthesia (general or spinal) for common pediatric urology procedures: undescended testicle, inguinal hernia, hypospadias, phimosis, and phimosis with penoscrotal webbing. Surveys were emailed to members of the SPU and ESPU. Responses and demographic information were collected and analyzed. RESULTS: The survey was completed by 113 SPU members (46% response rate for members who opened the invitation) and 109 ESPU members. For all clinical scenarios, < 20% of pediatric urologists from the SPU and <25% from the ESPU favor doing any procedure with spinal anesthesia. The majority of respondents practice in children's hospitals with pediatric anesthesiologists, but roughly half of the responders (54% SPU and 43% ESPU) do not think their anesthesia colleagues would be comfortable performing spinal anesthesia. Furthermore, only 51% of SPU and 36% of ESPU members discuss the possible neurodevelopmental side-effects of anesthesia with parents; similarly, less than half of all respondents think their anesthesia colleagues address these potential side-effects when obtaining consent. The only significant difference between SPU and ESPU responses was that ESPU members tended to delay penile surgery more than SPU respondents. CONCLUSION: Whether general anesthesia has any effect on the developing brain of children undergoing routine pediatric urology procedures is unclear. Yet, few pediatric urologists, independent of their region of practice, prefer spinal to general anesthesia. Collaboration in the OR is the key to success, and it is important that pediatric urologists and pediatric anesthesiologists work together to balance the benefits and risks of general and spinal anesthesia.

High-resolution perineal ultrasound of a paraurethral cyst in a neonate (2008: 8b).

We present high-resolution ultrasonography of a paraurethral cyst, a rare cause of an interlabial mass in a newborn. Although not always performed in these cases, ultrasonographic evaluation is an easily performed examination in assessment of the final diagnosis and therapeutic decisions.

Urine concentration and enuresis in healthy preschool children.

OBJECTIVES: To determine whether children concentrate their urine overnight and to assess the correlation between specific gravity of a first morning urine specimen and the results of a questionnaire concerning bedwetting, voiding habits, and continence in 47 healthy children aged 3 to 6 years. DESIGN: A prospective observer-blinded consecutive sample. SETTING: Two San Francisco, Calif., preschools. PARTICIPANTS: Forty-seven children attending preschool during the study period. MEASUREMENTS/MAIN RESULTS: Forty of 47 children had a urine specific gravity greater than 1.020. None of these children wet the bed during this study, although four (11%) of 36 had a history of bedwetting. Furthermore, seven children with a urine specific gravity of 1.015 or lower had a history of bedwetting and wet the bed during this study. A voiding frequency of six or more times per day, by history, was associated with a 3:1 relative risk of bedwetting but did not segregate children with primary enuresis from those with secondary enuresis. CONCLUSIONS: Our results indicate that healthy children aged 3 to 6 years are able to concentrate their urine. In addition, urine specific gravity was an accurate predictor of the presence of nocturnal enuresis in this group of children. Our results suggest that a specific gravity of the first morning urine specimen should be correlated with appropriate history before extensive diagnostic evaluation or empiric therapy is performed in children with nocturnal enuresis.

Post-traumatic high-flow priapism in a 6-year-old boy: management by percutaneous placement of bilateral vascular coils.

Post-traumatic high-flow priapism in children is a very rare disorder. Treatment of high-flow priapism by catheterization and embolization in children has been described only four times in published reports. To our knowledge, our case report is the first in which embolization was superselective and thus could be performed bilaterally.

Therapeutic laparoscopy for intra-abdominal testes.

Fourteen laparoscopic surgical procedures were performed in 10 children with 11 intra-abdominal testes. In addition to localizing the testes, laparoscopy aided in the surgical approach. In 8 patients, the first phase of a two-stage Fowler-Stephens orchiopexy was performed. Five children underwent an open surgical procedure three months later and have a viable testis in the scrotum after at least nine months of follow-up. In 5 patients (6 testicles), laparoscopy was used to dissect the testis. Three patients underwent the second phase of the two-stage Fowler-Stephens procedure laparoscopically. In all 3 patients, the testicle could be easily mobilized into the scrotum. Two other testicles were mobilized by dissecting the spermatic vessels up to the renal hilum laparoscopically; this allowed the intra-abdominal testes to come into the scrotum without dividing the spermatic vessels. In one teenager with a small intra-abdominal testis and a normal contralateral testis, laparoscopic orchiectomy was performed. We believe laparoscopy has a role both diagnostically and surgically in the treatment of intra-abdominal testes.

Pediatric ureteropelvic junction obstruction treated with retrograde endopyelotomy.

OBJECTIVES: To determine the feasibility of retrograde endopyelotomy in the management of pediatric ureteropelvic junction (UPJ) obstruction. METHODS: We treated 2 boys aged 4 and 6 years with the Acucise endopyelotomy device for symptomatic ureteropelvic junction obstruction. The Acucise device was placed over a Lunderquist guide wire with fluoroscopic guidance only and routine Double J catheters were left in situ for 6 weeks after the procedure. The morbidity of the treatment and the short-term outcome were assessed. RESULTS: There were no acute complications and short-term follow-up results were satisfactory as determined by intravenous urography and diuretic renography. CONCLUSIONS: Ureteropelvic junction obstruction in children may be treated by retrograde endopyelotomy with the Acucise device. The principal potential advantage of this procedure is reduced morbidity. Our findings suggest that further evaluation is warranted.

Bilateral Legg-Calvé-Perthes disease: different from unilateral disease?

Twenty-five patients or 50 hips with bilateral Legg-Calvé-Perthes disease were reviewed at skeletal maturity in the orthopaedic departments of Leuven, Belgium, and Montpellier, France. The two groups were very similar as to age at onset of the disease, severity of involvement, and classification at skeletal maturity. The results seem to indicate that bilateral disease runs a more severe course as compared with unilateral Legg-Calvé-Perthes disease. Eighty percent presented with a Catterall group III and IV and Herring classification B and C. Forty-eight percent rated as Stulberg 4 and 5 at skeletal maturity.

Value of clinical provocative tests in carpal tunnel syndrome.

The value of five provocative tests for the diagnosis of carpal tunnel syndrome (CTS) was assessed in four groups: 54 hands with confirmed CTS, 12 with typical symptoms but normal electrophysiological studies, 16 hands in persons with diabetes and 81 hands in normal controls. Compared to normal controls the Tinel sign and the closed first test are highly specific; Durkan's compression test is not useful to discriminate between symptomatic patients with and without EMG disturbances. The closed fist test is specific in these situations.

[Preliminary experiences with the use of the Holmium-YAG laser in the treatment of soft tissues and of cystine calculi in children]. / Premières expériences avec l'utilisation du laser Holmium-YAG dans le traitement des tissus mous et des calculs de cystine chez l'enfant.

INTRODUCTION: Experience of the use of the Holmium: Yttrium-Aluminium-Garnet (Ho:YAG) laser in children has been limited. However, the Ho:YAG laser has been in clinical use in urology for several years but has mainly been used for the treatment of renal stones and benign prostatic hyperplasia. Due to its unique combination of vaporization and coagulation, the Ho:YAG laser allows a precise cutting action. The depth of penetration in water and tissue is limited to < 0.5 mm and therefore provides a safety margin. The Ho:YAG laser can be used in children, as the energy can be delivered via fibers that range from 200 to 1000 mu in diameter. MATERIALS AND METHODS: We used the Ho:YAG laser in 5 children (2-15 years): one child (2 years) with bladder exstrophy had a urethral stricture after bladder neck reconstruction, two children (6 years and 14 years) had ureteropelvic junction (UPJ) stenosis and refused open surgery and two children (5 years and 15 years) suffered from cystine stones (ESWL failed). The urethral stricture was incised in a retrograde fashion. We performed an antegrade incision of the UPJ with the Ho:YAG laser in the 6-year-old child and a retrograde incision in the 14-year-old child. We removed the stones in antegrade fashion in the 5-year-old child and in retrograde fashion in the 15-year-old child. RESULTS: All children now have more than 12 month's follow-up. There were no immediate or late complications. The boy with urethral stricture remained free of recurrence, the boy with UPJ stenosis obtained improved drainage on the excretory renogram and the two children with cystine stones remained stonefree. CONCLUSION: We have shown that the safety and efficacy of the Ho:YAG laser is also reproducible in urologic pathology in children. In addition, due to its vaporizing quality, the Ho:YAG laser is more effective in the treatment of cystine stones and allows minimaly invasive treatment in children.

Fermi observations of high-energy gamma-ray emission from GRB 080916C.

Gamma-ray bursts (GRBs) are highly energetic explosions signaling the death of massive stars in distant galaxies. The Gamma-ray Burst Monitor and Large Area Telescope onboard the Fermi Observatory together record GRBs over a broad energy range spanning about 7 decades of gammaray energy. In September 2008, Fermi observed the exceptionally luminous GRB 080916C, with the largest apparent energy release yet measured. The high-energy gamma rays are observed to start later and persist longer than the lower energy photons. A simple spectral form fits the entire GRB spectrum, providing strong constraints on emission models. The known distance of the burst enables placing lower limits on the bulk Lorentz factor of the outflow and on the quantum gravity mass.

Measurement of the cosmic ray e+ +e- spectrum from 20 GeV to 1 TeV with the Fermi Large Area Telescope.

Designed as a high-sensitivity gamma-ray observatory, the Fermi Large Area Telescope is also an electron detector with a large acceptance exceeding 2 m;{2} sr at 300 GeV. Building on the gamma-ray analysis, we have developed an efficient electron detection strategy which provides sufficient background rejection for measurement of the steeply falling electron spectrum up to 1 TeV. Our high precision data show that the electron spectrum falls with energy as E-3.0 and does not exhibit prominent spectral features. Interpretations in terms of a conventional diffusive model as well as a potential local extra component are briefly discussed.

The Fermi Gamma-Ray Space Telescope discovers the pulsar in the young galactic supernova remnant CTA 1.

Energetic young pulsars and expanding blast waves [supernova remnants (SNRs)] are the most visible remains after massive stars, ending their lives, explode in core-collapse supernovae. The Fermi Gamma-Ray Space Telescope has unveiled a radio quiet pulsar located near the center of the compact synchrotron nebula inside the supernova remnant CTA 1. The pulsar, discovered through its gamma-ray pulsations, has a period of 316.86 milliseconds and a period derivative of 3.614 x 10(-13) seconds per second. Its characteristic age of 10(4) years is comparable to that estimated for the SNR. We speculate that most unidentified Galactic gamma-ray sources associated with star-forming regions and SNRs are such young pulsars.

Role of nitric oxide in fetal lower urinary tract function.

We studied the role of nitric oxide (NO) in normal function of the lower urinary tract in fetal lambs. Fetal surgery was performed in pregnant ewes at 118 days' gestation (term 145-days) to place arterial, venous, and double-lumen urachal catheters. Five animals had a catheter secured in the distal urethra (to measure voided volume), and six underwent ligation of the urethra. Urodynamic studies were performed via the urachal catheter under baseline conditions, during systemic blockade of NO synthesis with N omega-nitro-L-arginine, and with systemic NO stimulation by L-arginine 48 hours postoperatively. Nitric oxide blockade caused an 88% mean increase in bladder capacity (volume to initiation of voiding) (p < 0.001) and a 5.8-fold increase in mean postvoid residual volume (p < 0.0001) despite normal maximal bladder pressures, suggesting inadequate sphincteric relaxation. Qualitatively, NO inhibition increased the presence of low-level bladder contractions and caused a trend toward decreased bladder compliance. Increase of NO substrate by L-arginine infusion restored baseline findings if performed after N omega-nitro-L-arginine. Stimulation of NO by L-arginine infusion caused continuous efflux of the infusate secondary to a persistently open sphincter. In conclusion, NO is active in the function of the lower urinary tract in the fetal lamb and appears to influence both sphincter and detrusor activity.